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Title:
Effects of unbalanced diets on cerebral glucose metabolism in the adult rat
Authors:
al-Mudallal, A. S.; Levin, B. E.; Lust, W. D.; Harik, S. I.
Abstract:
We measured regional cerebral metabolic rates for glucose and selected cerebral metabolites in rats fed one of the following diets for 6 to 7 weeks: (1) regular laboratory chow; (2) high-fat, carbohydrate-free ketogenic diet deriving 10% of its caloric value from proteins and 90% from fat; and (3) high-carbohydrate diet deriving 10% of its caloric value from proteins, 78% from carbohydrates, and 12% from fat. In preliminary experiments, we found that moderate ketosis could not be achieved by diets deriving less than about 90% of their caloric value from fat. Rats maintained on the ketogenic diet had moderately elevated blood beta-hydroxybutyrate (O.4 mM) and acetoacetate (0.2 mM), and a five- to 10-fold increase in their cerebral beta-hydroxybutyrate level. Cerebral levels of glucose, glycogen, lactate, and citrate were similar in all groups. 2-Deoxyglucose studies showed that the ketogenic diet did not significantly alter regional brain glucose utilization. However, rats maintained on the high-carbohydrate diet had a marked decrease in their brain glucose utilization and increased cerebral concentrations of glucose 6-phosphate. These findings indicate that long-term moderate ketonemia does not significantly alter brain glucose phosphorylation. However, even marginal protein dietary deficiency, when coupled with a carbohydrate-rich diet, depresses cerebral glucose utilization to a degree often seen in metabolic encephalopathies. Our results support the clinical contention that protein dietary deficiency coupled with increased carbohydrate intake can lead to CNS dysfunction.
Published:
1995-12
Title:
Effects of unbalanced diets on cerebral glucose metabolism in the adult rat
Authors:
al-Mudallal, A. S.; Levin, B. E.; Lust, W. D.; Harik, S. I.
Abstract:
We measured regional cerebral metabolic rates for glucose and selected cerebral metabolites in rats fed one of the following diets for 6 to 7 weeks: (1) regular laboratory chow; (2) high-fat, carbohydrate-free ketogenic diet deriving 10% of its caloric value from proteins and 90% from fat; and (3) high-carbohydrate diet deriving 10% of its caloric value from proteins, 78% from carbohydrates, and 12% from fat. In preliminary experiments, we found that moderate ketosis could not be achieved by diets deriving less than about 90% of their caloric value from fat. Rats maintained on the ketogenic diet had moderately elevated blood beta-hydroxybutyrate (O.4 mM) and acetoacetate (0.2 mM), and a five- to 10-fold increase in their cerebral beta-hydroxybutyrate level. Cerebral levels of glucose, glycogen, lactate, and citrate were similar in all groups. 2-Deoxyglucose studies showed that the ketogenic diet did not significantly alter regional brain glucose utilization. However, rats maintained on the high-carbohydrate diet had a marked decrease in their brain glucose utilization and increased cerebral concentrations of glucose 6-phosphate. These findings indicate that long-term moderate ketonemia does not significantly alter brain glucose phosphorylation. However, even marginal protein dietary deficiency, when coupled with a carbohydrate-rich diet, depresses cerebral glucose utilization to a degree often seen in metabolic encephalopathies. Our results support the clinical contention that protein dietary deficiency coupled with increased carbohydrate intake can lead to CNS dysfunction.
Published:
1995-12
Title:
Emergency appendicectomy and meat consumption in the UK
Authors:
Appleby, P.; Thorogood, M.; McPherson, K.; Mann, J.
Abstract:
STUDY OBJECTIVE: To compare the rates of reported emergency appendicectomies in a cohort study of vegetarians and non-vegetarians by participants' history of meat consumption. DESIGN: This was a prospective cohort study in which participants were asked about their lifetime history of meat consumption/avoidance and, separately, whether they had had an appendicectomy. Appendicectomy was described as either "emergency" or "non-emergency" according to details supplied by the participant. SETTING: The United Kingdom. PARTICIPANTS: These comprised more than 11000 people, of whom 4852 (44%) completed both an appendicectomy form and a dietary questionnaire giving details of their lifetime history of meat consumption. MAIN RESULTS: The percentage who reported an emergency appendicectomy was higher among lifelong meat eaters (10.7%) than either lifelong non-meat eaters (7.8%) or those who had stopped eating meat (8.0%); and the operations were performed at an earlier age in this first group (mean values 18.9, 26.0, and 19.6 years respectively). The overall age adjusted emergency participants who did not eat mean with those who ate meat was 0.47 (95% confidence interval 0.35, 0.65). CONCLUSION: The results suggests that people who do not eat meat have a 50% lower risk of requiring an emergency appendicectomy than those who do. The data do not, however, allow the reliable testing of other hypotheses, so meat consumption may simply be a marker for another dietary, lifestyle, or socioeconomic factor.
Published:
1995-12
Title:
Immunological influences in attention-deficit disorder and schizophrenia; is there a link between these two conditions?
Authors:
Holden, R. J.; Pakula, I. S.
Abstract:
This paper aims to explore the influence of the immune system on the pathobiochemistry of movement disorders (Tourette syndrome, obsessive compulsive disorders and attention-deficit disorder, with and without hyperactivity) and schizophrenia. In children, a temporal relationship has been observed between contraction of a group A beta-hemolytic streptococcal infection and subsequent presentation with one of the movement disorders. Pathology investigations reveal that elevated antineuronal antibodies are associated with movement disorders. Similarly, elevations in interleukin-1 beta and interleukin-6 have been reported in schizophrenia. It is now known that the immune system can be activated by conditions other than a viral or bacterial infection, such as: neurological insult, neurotoxicity--endogenous and environmental, neurotransmitter and cholesterol dysregulation. These latter avenues of immune system activation will be explored with respect to schizophrenia.
Published:
1995-12
Title:
Iron and zinc status of young women aged 14 to 19 years consuming vegetarian and omnivorous diets
Authors:
Donovan, U. M.; Gibson, R. S.
Abstract:
OBJECTIVE: To assess the iron and zinc status of young females, aged 14 to 19 years, consuming vegetarian and omnivorous diets. METHODS: Dietary intakes (via 3-day weighed food records), BMI, and laboratory indices of iron and zinc status were compared in a convenience sample of 79 lacto-ovo-vegetarians (LOV), 16 semi-vegetarians (SV), and 29 omnivorous (OM) females. RESULTS: Twenty-nine percent LOV, 44% SV, and 17% OM had low iron stores (i.e., plasma ferritin < 12 micrograms/L); only 3% had anemia. As well, 24% LOV, 33% SV, and 18% OM had serum zinc < 10.71 mumol/L and 14% LOV, 14% SV, and 17% OM had hair zinc < 1.68 mumol/g. Intakes of iron and ascorbic acid from the weighed food records were associated with serum iron (p < 0.04) and total iron binding capacity (negatively; p < 0.02), respectively, whereas Phy:Zn molar ratios were associated with serum zinc (negatively; p < 0.04). Z-scores for BMI were associated with serum zinc (p < 0.02) and diet type (p < 0.001); serum AP activity was associated with age (p < 0.0001) and oral contraceptive use (p
Published:
1995-10
Title:
Mortality in participants and non-participants of a multifactorial prevention study of cardiovascular diseases: a 28 year follow up of the Helsinki Businessmen Study.
Authors:
Strandberg, T. E.; Salomaa, V. V.; Vanhanen, H. T.; Naukkarinen, V. A.; Sarna, S. J.; Miettinen, T. A.
Abstract:
OBJECTIVE--To investigate pretrial risk factors and long term mortality (1964-1992) in participants and non-participants of a multifactorial primary prevention trial. DESIGN--A prospective study among 3313 initially healthy businessmen. During the 1960s (1964 onwards), 3490 healthy male business executives born between 1919 and 1934 participated in voluntary health checks at the Institute of Occupational Health in Helsinki. From that period cardiovascular disease (CVD) risk factors were available in 3313 men. In the beginning of the 1970s these men were invited to join a multifactorial primary prevention trial of CVD. Six groups were formed: (I) healthy participants in a high risk intervention group (n = 612), and (II) their randomised control group (n = 610); (III) a non-participant low risk group (n = 593); (IV) an excluded group with signs of CVD (n = 563); (V) a refused group (n = 867); and (VI) dead (n = 68). Groups I and II participated in the five year prevention trial which started in 1974. Other groups were followed up through registers, with no personal contact. MEASUREMENTS--Cardiovascular risk factors during the 1960s. Mortality follow up using national registers up to 31 December, 1992. MAIN RESULTS--Baseline risk factors were lowest in the low risk group, highest in the excluded group, intermediate and comparable in other groups. Eighteen-year (1974-1992) mortality (per 1000) was 79.3, 106.6, 155.2, 179.9, and 259.3 in the low risk, control, intervention, refused, and excluded groups, respectively (P
Published:
1995-10
Title:
Potential role of raising dietary protein intake for reducing risk of atherosclerosis
Authors:
Wolfe, B. M.
Abstract:
OBJECTIVE: To ascertain the effect on plasma lipoprotein lipids of substituting moderate amounts of protein for carbohydrate in human diets. DESIGN: Subjects were first stabilized on the desired fat intake for one to two weeks. Using a cross-over design, subjects were randomly allocated to either the high or low protein diet for four to five weeks and then switched to the alternative diet for four to five more weeks. Fasting venous blood was obtained weekly. SETTING: Subjects were studied in tertiary care lipid clinic setting. PATIENTS: Studies in two groups of hypercholesterolemic subjects have been completed: group MH - 10 subjects with moderate hypercholesterolemia (5.8 to 8.0 mmol/L) and group FH - five subjects with familial hypercholesterolemia (more than 8.2 mmol/L prior to treatment with cholestyramine). Preliminary findings in Group NL - six normolipidemic subjects (3.5 to 4.9 mmol/L) are also discussed briefly. INTERVENTIONS: Body weight, intakes of fat, fibre and cholesterol and fat composition were constant. Either 11, 17 or 10% of total energy from protein was exchanged for carbohydrate in groups MH, FH and NL, respectively. MAIN RESULTS: Exchange of dietary protein for carbohydrate: significantly reduced mean plasma low density lipoprotein (LDL) cholesterol 6% in group MH and 9% in group NL (P < 0.02); significantly increased mean fasting plasma high density lipoprotein (HDL) cholesterol by 12% in group MH and by 17% in group FH (P < 0.01); significantly reduced the mean value for the ratio of plasma total cholesterol to HDL cholesterol by 15% in group MH and by 16% in group FH (P < 0.05); and significantly reduced fasting total triglycerides by 23% in groups MH and FH and by 18% in NL (P
Published:
1995-10
Title:
Rapid reduction of serum cholesterol and blood pressure by a twelve-day, very low fat, strictly vegetarian diet
Authors:
McDougall, J.; Litzau, K.; Haver, E.; Saunders, V.; Spiller, G. A.
Abstract:
OBJECTIVE: This study was conducted to demonstrate the effectiveness of a strictly vegetarian, very low-fat diet on cardiac risk factor modification. METHODS: Five hundred men and women, participants in an intensive 12-day live-in program, were studied. The program focused on dietary modification, moderate exercise, and stress management at a hospital-based health-center. RESULTS: During this short time period, cardiac risk factors improved: there was an average reduction of total serum cholesterol of 11% (p < 0.001), of blood pressure of 6% (p or = 65 years with serum cholesterol
Published:
1995-10
Title:
Vitamin B-12 status of long-term adherents of a strict uncooked vegan diet ("living food diet") is compromised
Authors:
Rauma, A. L.; Törrönen, R.; Hänninen, O.; Mykkänen, H.
Abstract:
The present study examined the vitamin B-12 status in long-term adherents of a strict uncooked vegan diet called the "living food diet." The study was comprised of two parts. In the cross-sectional part, the data on serum vitamin B-12 concentrations and dietary intakes in 21 (1 male, 20 females) long-term adherents (mean 5.2 y, range 0.7-14) of the "living food diet" were compared with those of 21 omnivorous controls matched for sex, age, social status and residence. In the longitudinal part of the study, food consumption data were collected and blood samples were taken from nine "living food eaters" (1 male, 8 females) on two occasions 2 y apart. The cross-sectional study revealed significantly (P < 0.001, paired t test) lower serum vitamin B-12 concentrations in the vegans (mean 193 pmol/L, range 35-408) compared with their matched omnivorous controls (311, 131-482). In the vegan group, total vitamin B-12 intake correlated significantly (r = 0.63, P
Published:
1995-10
Title:
Five-year survival rates of melanoma patients treated by diet therapy after the manner of Gerson: a retrospective review
Authors:
Hildenbrand, G. L.; Hildenbrand, L. C.; Bradford, K.; Cavin, S. W.
Abstract:
OBJECTIVE: Compare 5-year melanoma survival rates to rates in medical literature. DESIGN: Retrospective. SETTING: Hospital in Tijuana, Mexico. PATIENTS: White adult patients (N = 153) with superficial spreading and nodular melanoma, aged 25-72 years. INTERVENTION: Gerson's diet therapy: lactovegetarian; low sodium, fat and (temporarily) protein; high potassium, fluid, and nutrients (hourly raw vegetable/fruit juices). Metabolism increased by thyroid; calorie supply limited to 2600-3200 calories per day. Coffee enemas as needed for pain and appetite. MAIN OUTCOME MEASURE: 5-year survival rates by stage at admission. RESULTS: Of 14 patients with stages I and II (localized) melanoma, 100% survived for 5 years, compared with 79% of 15,798 reported by Balch. Of 17 with stage IIIA (regionally metastasized) melanoma, 82% were alive at 5 years, in contrast to 39% of 103 from Fachklinik Hornheide. Of 33 with combined stages IIIA + IIIB (regionally metastasized) melanoma, 70% lived 5 years, compared with 41% of 134 from Fachklinik Hornheide. We propose a new stage division: IVA (distant lymph, skin, and subcutaneous tissue metastases), and IVB (visceral metastases). Of 18 with stage IVA melanoma, 39% were alive at 5 years, compared with only 6% of 194 from the Eastern Cooperative Oncology Group. Survival impact was not assessed for stage IVB. Male and female survival rates were identical for stages I-IIIB, but stage IVA women had a strong survival advantage. CONCLUSIONS: The 5-year survival rates reported here are considerably higher than those reported elsewhere. Stage IIIA/B males had exceptionally high survival rates compared with those reported by other centers.
Published:
1995-09
Title:
Identification of galectin-3 as a high-affinity binding protein for advanced glycation end products (AGE): a new member of the AGE-receptor complex.
Authors:
Vlassara, H.; Li, Y. M.; Imani, F.; Wojciechowicz, D.; Yang, Z.; Liu, F. T.; Cerami, A.
Abstract:
BACKGROUND: Advanced glycation end products (AGE), the reactive derivatives of nonenzymatic glucose-protein condensation reactions, are implicated in the multiorgan complications of diabetes and aging. An AGE-specific cellular receptor complex (AGE-R) mediating AGE removal as well as multiple biological responses has been identified. By screening an expression library using antibody against a previously identified component of the AGE-R complex p90, a known partial cDNA clone was isolated with homology to galectin-3, a protein of diverse identity, and member of the galectin family. MATERIALS AND METHODS: To explore this unexpected finding, the nature of the interactions between galectin-3 and AGE was studied using intact macrophage-like RAW 264.7 cells, membrane-associated and recombinant galectin-1 through -4, and model AGE-ligands (AGE-BSA, FFI-BSA). RESULTS: Among the members of this family (galectin-1 through 4), recombinant rat galectin-3 was found to exhibit high-affinity 125I-AGE-BSA binding with saturable kinetics (kD 3.5 x 10(7) M-1) that was fully blocked by excess unlabeled naturally formed AGE-BSA or synthetic FFI-BSA, but only weakly inhibited by several known galectin-3 ligands, such as lactose. In addition to the p90, immunoprecipitation with anti-galectin-3, followed by 125I-AGE-BSA ligand blot analysis of RAW 264.7 cell extracts, revealed galectin-3 (28 and 32 kD), as well as galectin-3-associated proteins (40 and 50 kD) with AGE-binding activity. Interaction of galectin-3 with AGE-BSA or FFI-BSA resulted in formation of SDS-, and beta-mercaptoethanol-insoluble, but hydroxylamine-sensitive high-molecular weight complexes between AGE-ligand, galectin-3, and other membrane components. CONCLUSIONS: The findings point toward a mechanism by which galectin-3 may serve in the assembly of AGE-R components and in the efficient cell surface attachment and endocytosis by macrophages of a heterogenous pool of AGE moieties with diverse affinities, thus contributing to the elimination of these pathogenic substances.
Published:
1995-09
Title:
Neurometrics, dynamic brain imaging and attention deficit hyperactivity disorder
Authors:
Levy, F.; Ward, P. B.
Abstract:
OBJECTIVE: The literature on the development of frequency analysis of the electroencephalogram (neurometrics) and functional dynamic brain imaging techniques is reviewed. Clinical applications in the diagnosis and treatment of learning disorders of childhood are discussed. CONCLUSIONS: While questions remain about the sensitivity and specificity of the neurometric method in diagnosing attention deficit hyperactivity disorder (ADHD), if the technique proved predictive of medication response, its importance would be established. However, evoked-potential studies, cerebral blood flow and cerebral glucose metabolic studies promise a better understanding of underlying psychological processes in ADHD.
Published:
1995-08
Title:
ADHD and thyroid abnormalities: a research note
Authors:
Spencer, T.; Biederman, J.; Wilens, T.; Guite, J.; Harding, M.
Abstract:
Contradictory findings have been reported on associations between ADHD and thyroid abnormalities including the syndrome of generalized resistance to thyroid hormone. We systematically reviewed thyroid function in a large group of children and adolescents with ADHD (N = 132). We failed to find evidence of generalized resistance to thyroid hormone. Although mild laboratory abnormalities in thyroid function were observed in a minority of ADHD subjects, they were not different than rates reported in the literature for normal children.
Published:
1995-07
Title:
Digestibility of dietary fiber components in vegetarian men
Authors:
Joshi, S.; Agte, V.
Abstract:
Digestibility of fiber components namely neutral detergent fiber (total content of cellwall) cellulose, hemicellulose and lignin are estimated in 14 healthy vegetarian men during adlibitum feeding and at 3 energy levels namely 2526, 2868 and 3290 kcals/day. Values of digestibility for adlibitum experiments were 34.17 +/- 2.3 for neutral detergent fiber (NDF), 30.1 +/- 3.9 for cellulose and 53.4 +/- 3.0 for hemicellulose and 8.1 +/- 2.6 for lignin. There was a considerable variability in digestibility of fiber components between individuals.
Published:
1995-07
Title:
Digestibility of dietary fiber components in vegetarian men
Authors:
Joshi, S.; Agte, V.
Abstract:
Digestibility of fiber components namely neutral detergent fiber (total content of cellwall) cellulose, hemicellulose and lignin are estimated in 14 healthy vegetarian men during adlibitum feeding and at 3 energy levels namely 2526, 2868 and 3290 kcals/day. Values of digestibility for adlibitum experiments were 34.17 +/- 2.3 for neutral detergent fiber (NDF), 30.1 +/- 3.9 for cellulose and 53.4 +/- 3.0 for hemicellulose and 8.1 +/- 2.6 for lignin. There was a considerable variability in digestibility of fiber components between individuals.
Published:
1995-07
Title:
Effects of duodenal and distal ileal infusions of glucose and oleic acid on meal patterns in rats
Authors:
Woltman, T.; Reidelberger, R.
Abstract:
The mechanisms mediating the anorexic effects of nutrients in the proximal and distal small intestine are not clearly understood. We determined the dose-dependent effects of duodenal and distal ileal infusions of glucose and oleic acid on meal patterns in ad libitum feeding rats. Rats with cannulas in both the duodenum and ileum received a 2-h infusion of glucose (0, 800, 1,600, 3,200, 6,400, or 12,800 mumol/h) or oleic acid (0, 48, 240, 640, or 1,280 mumol/h) into the duodenum or ileum at the start of the dark period, and meal patterns were monitored for 4 h. Cumulative food intake was inhibited dose dependently by ileal as well as duodenal infusion of both glucose and oleic acid. Ileal glucose was more inhibitory than duodenal glucose, whereas duodenal oleic acid was more inhibitory than ileal oleic acid. Duodenal glucose and oleic acid inhibited feeding by decreasing meal frequency; ileal oleic acid decreased only meal size, whereas ileal glucose reduced both meal size and frequency. We interpret these results to suggest that ileal oleic acid and glucose suppress feeding by different mechanisms and that these mechanisms differ from those mediating the anorexic responses to oleic acid and glucose in the duodenum.
Published:
1995-07
Title:
Fat and carbohydrate overfeeding in humans: different effects on energy storage
Authors:
Horton, T. J.; Drougas, H.; Brachey, A.; Reed, G. W.; Peters, J. C.; Hill, J. O.
Abstract:
Both the amount and composition of food eaten influence body-weight regulation. The purpose of this study was to determine whether and by what mechanism excess dietary fat leads to greater fat accumulation than does excess dietary carbohydrate. We overfed isoenergetic amounts (50% above energy requirements) of fat and carbohydrate (for 14 d each) to nine lean and seven obese men. A whole-room calorimeter was used to measure energy expenditure and nutrient oxidation on days 0, 1, 7, and 14 of each overfeeding period. From energy and nutrient balances (intake-expenditure) we estimated the amount and composition of energy stored. Carbohydrate overfeeding produced progressive increases in carbohydrate oxidation and total energy expenditure resulting in 75-85% of excess energy being stored. Alternatively, fat overfeeding had minimal effects on fat oxidation and total energy expenditure, leading to storage of 90-95% of excess energy. Excess dietary fat leads to greater fat accumulation than does excess dietary carbohydrate, and the difference was greatest early in the overfeeding period.
Published:
1995-07
Title:
Medical aspects of ketone body metabolism
Authors:
Mitchell, G. A.; Kassovska-Bratinova, S.; Boukaftane, Y.; Robert, M. F.; Wang, S. P.; Ashmarina, L.; Lambert, M.; Lapierre, P.; Potier, E.
Abstract:
Ketone bodies are produced in the liver, mainly from the oxidation of fatty acids, and are exported to peripheral tissues for use as an energy source. They are particularly important for the brain, which has no other substantial non-glucose-derived energy source. The 2 main ketone bodies are 3-hydroxybutyrate (3HB) and acetoacetate (AcAc). Biochemically, abnormalities of ketone body metabolism can present in 3 fashions: ketosis, hypoketotic hypoglycemia, and abnormalities of the 3HB/AcAc ratio. Normally, the presence of ketosis implies 2 things: that lipid energy metabolism has been activated and that the entire pathway of lipid degradation is intact. In rare patients, ketosis reflects an inability to utilize ketone bodies. Ketosis is normal during fasting, after prolonged exercise, and when a high-fat diet is consumed. During the neonatal period, infancy and pregnancy, times at which lipid energy metabolism is particularly active, ketosis develops readily. Pathologic causes of ketosis include diabetes, ketotic hypoglycemia of childhood, corticosteroid or growth hormone deficiency, intoxication with alcohol or salicylates, and several inborn errors of metabolism. The absence of ketosis in a patient with hypoglycemia is abnormal and suggests the diagnosis of either hyperinsulinism or an inborn error of fat energy metabolism. An abnormal elevation of the 3HB/AcAc ratio usually implies a non-oxidized state of the hepatocyte mitochondrial matrix resulting from hypoxia-ischemia or other causes. We summarize the differential diagnosis of abnormalities of ketone body metabolism, as well as pertinent recent advances in research.
Published:
1995-06
Title:
MtDNA mutation in MERRF syndrome causes defective aminoacylation of tRNA Lys and premature translation termination
Authors:
Enriquez, José Antonio; Chomyn, Anne; Attardi, Giuseppe
Abstract:
We have investigated the pathogenetic mechanism of the mitochondrial tRNA Lys gene mutation (position 8344) associated with MERRF encephalomyopathy in several mitochondrial DMA (mtDNA)–less cell transformants carrying the mutation and in control cells. A decrease of 50–60% in the specific tRNA Lys aminoacylation capacity per cell was found in mutant cells. Furthermore, several lines of evidence reveal that the severe protein synthesis impairment in MERRF mutation–carrying cells is due to premature termination of translation at each or near each lysine codon, with the deficiency of aminoacylated tRNA Lys being the most likely cause of this phenomenon. © 1995 Nature Publishing Group.
Published:
1995-05
Title:
Role for circulating lipoproteins in protection from endotoxin toxicity
Authors:
Feingold, K. R.; Funk, J. L.; Moser, A. H.; Shigenaga, J. K.; Rapp, J. H.; Grunfeld, C.
Abstract:
Previous studies have shown that endotoxin (lipopolysaccharide [LPS])-induced death can be prevented by preincubating LPS with lipoproteins in vitro or by infusing large quantities of lipids into animals prior to LPS administration. In the present study we determined whether physiological levels of lipids also provide protection. Serum lipid levels were decreased by two different mechanisms: administration of 4-aminopyrolo-(3,4-D)pyrimide, which prevents the hepatic secretion of lipoproteins, and administration of pharmacological doses of estradiol, which increases the number of hepatic low-density lipoprotein receptors, leading to increased lipoprotein clearance. In both hypolipidemic models, LPS-induced mortality is markedly increased compared with that of controls with normal serum lipid levels. In both hypolipidemic models, administration of exogenous lipoproteins, which increase levels of serum lipids into the physiological range, reduces the increased mortality to levels similar to that seen in normal animals. In normal lipidemic animals, 63% of 125I-LPS in plasma is associated with lipoproteins, where it would not be capable of stimulating cytokine production. In contrast, in hypolipidemic animals, very little LPS (12 to 17%) is associated with lipoproteins. Rather, more LPS is in the lipoprotein-free plasma compartment, where it could exert biological effects. In both hypolipidemic models, LPS produces a greater increase in serum tumor necrosis factor levels than it does in controls (three- to fivefold increase), and administration of exogenous lipoproteins prevents this increase. Cytokines, in particular tumor necrosis factor, are responsible for most of the toxic effects of LPS. These data provide evidence that physiological levels of serum lipids protect animals from LPS toxicity. Thus, lipoproteins, in addition to playing a role in lipid transport, may have protective functions. Moreover, as part of the immune response, cytokine-induced increases in serum lipid levels may play a role in host defense by decreasing the toxicities of biological and chemical agents.
Published:
1995-05
Title:
Effects of a ketogenic diet on tumor metabolism and nutritional status in pediatric oncology patients: two case reports
Authors:
Nebeling, L. C.; Miraldi, F.; Shurin, S. B.; Lerner, E.
Abstract:
OBJECTIVE: Establish dietary-induced ketosis in pediatric oncology patients to determine if a ketogenic state would decrease glucose availability to certain tumors, thereby potentially impairing tumor metabolism without adversely affecting the patient's overall nutritional status. DESIGN: Case report. SETTING: University Hospitals of Cleveland. SUBJECTS: Two female pediatric patients with advanced stage malignant Astrocytoma tumors. INTERVENTIONS: Patients were followed as outpatients for 8 weeks. Ketosis was maintained by consuming a 60% medium chain triglyceride oil-based diet. MAIN OUTCOME MEASURES: Tumor glucose metabolism was assessed by Positron Emission Tomography (PET), comparing [Fluorine-18] 2-deoxy-2-fluoro-D-glucose (FDG) uptake at the tumor site before and following the trial period. RESULTS: Within 7 days of initiating the ketogenic diet, blood glucose levels declined to low-normal levels and blood ketones were elevated twenty to thirty fold. Results of PET scans indicated a 21.8% average decrease in glucose uptake at the tumor site in both subjects. One patient exhibited significant clinical improvements in mood and new skill development during the study. She continued the ketogenic diet for an additional twelve months, remaining free of disease progression. CONCLUSION: While this diet does not replace conventional antineoplastic treatments, these preliminary results suggest a potential for clinical application which merits further research.
Published:
1995-04
Title:
Greater oxidative susceptibility of the surface monolayer in small dense LDL may contribute to differences in copper-induced oxidation among LDL density subfractions
Authors:
Tribble, D. L.; Krauss, R. M.; Lansberg, M. G.; Thiel, P. M.; van den Berg, J. J.
Abstract:
We monitored peroxidative stress in the surface monolayer as compared with the outer core of large, buoyant (d 1.025-1.032 g/ml) and small, dense (d 1.040-1.054 g/ml) low density lipoprotein (LDL) subfractions using the oxidation-labile fluorescent probes parinaric acid (PnA) and parinaric acid methyl ester (PnME), which partition preferentially into these respective regions of LDL. Oxidation was initiated either with CuSO4 (5 microM) or the iron (Fe3+)-containing lipophilic complex hemin (1.0 microM) plus cumene hydroperoxide to facilitate heme degradation. In the presence of Cu2+, PnA was depleted significantly more rapidly than PnME in dense (P = 0.039) but not in buoyant LDL, suggesting that surface vulnerability is enhanced in dense LDL particles. With hemin, PnA and PnME were similarly susceptible within both subfractions, although there was a trend toward slower loss of PnA in buoyant LDL (P = 0.10), consistent with the internal site of initiation and a greater surface resistance in buoyant particles. As indicated by conjugated diene lag times, dense LDL was more susceptible than buoyant LDL to oxidation by Cu2+ (P = 0.03) but not hemin (P = 0.68). These results suggest that the increased susceptibility of dense LDL to oxidation by external agents such as Cu2+ is at least partially mediated by an enhanced vulnerability of the surface compartment.
Published:
1995-04
Title:
The Expensive-Tissue Hypothesis: The Brain and the Digestive System in Human and Primate Evolution
Authors:
Aiello, Leslie C.; Wheeler, Peter
Abstract:
Brain tissue is metabolically expensive, but there is no significant correlation between relative basal metabolic rate and relative brain size in humans and other encephalized mammals. The expensive-tissue hypothesis suggests that the metabolic requirements of relatively large brains are offset by a corresponding reduction of the gut. The splanchnic organs (liver and gastrointestinal tract) are as metabolically expensive as brains, and the gut is the only one of the metabolically expensive organs in the human body that is markedly small in relation to body size. Gut size is highly correlated with diet, and relatively small guts are compatible only with high-quality, easy-to-digest food. The often-cited relationship between diet and relative brain size is more properly viewed as a relationship between relative brain size and relative gut size, the latter being determined by dietary quality. No matter what is selecting for relatively large brains in humans and other primates, they cannot be achieved without a shift to a high-quality diet unless there is a rise in the metabolic rate. Therefore the incorporation of increasingly greater amounts of animal products into the diet was essential in the evolution of the large human brain.
Published:
1995-04
Title:
Urban/rural differences in red blood cell fatty acid composition, plasma lipids and diet in Melanesian Fijians
Authors:
Sutherland, W. H.; Shilton, M. E.; Nye, E. R.; Gillies, M. E.; Bakani, I.; Robertson, M. C.
Abstract:
OBJECTIVE: The aim of the study was to compare red blood cell (RBC) fatty acid composition, plasma lipids and lipoproteins and dietary intake between urban and rural Melanesian Fijians. DESIGN: A cross-sectional study was performed in a random subsample (n = 154) from a total survey population of 589 subjects. SETTING: Melanesian Fijians living in the relatively urban settlement of Nabua, Suva and On the remote island of Qamea (rural) were studied. RESULTS: The proportions of myristic acid (1.4% versus 0.3%, P < 0.001) and arachidonic acid (10.1% versus 11.4%, P < 0.01) were significantly higher and proportions of oleic acid (14.4% versus 13.2%, P < 0.05) and linoleic acid (11.9% versus 8.1%, P < 0.001) were significantly lower in RBC from rural compared with urban men, and a similar pattern was seen in women. Plasma cholesterol levels were significantly (P
Published:
1995-04
Title:
Biomarkers for assessing environmental exposure to carcinogens in the diet
Authors:
Strickland PT; Groopman JD
Abstract:
Published:
1995-03
Title:
Decrease in anti-Proteus mirabilis but not anti-Escherichia coli antibody levels in rheumatoid arthritis patients treated with fasting and a one year vegetarian diet
Authors:
Kjeldsen-Kragh, J.; Rashid, T.; Dybwad, A.; Sioud, M.; Haugen, M.; Førre, O.; Ebringer, A.
Abstract:
OBJECTIVE: To measure Proteus mirabilis and Escherichia coli antibody levels in patients with rheumatoid arthritis (RA) during treatment by vegetarian diet. METHODS: Sera were collected from 53 RA patients who took part in a controlled clinical trial of fasting and a one year vegetarian diet. P mirabilis and E coli antibody levels were measured by an indirect immunofluorescence technique and an enzyme immunoassay, respectively. RESULTS: The patients on the vegetarian diet had a significant reduction in the mean anti-proteus titres at all time points during the study, compared with baseline values (all p < 0.05). No significant change in titre was observed in patients who followed an omnivorous diet. The decrease in anti-proteus titre was greater in the patients who responded well to the vegetarian diet compared with diet non-responders and omnivores. The total IgG concentration and levels of antibody against E coli, however, were almost unchanged in all patient groups during the trial. The decrease from baseline in proteus antibody levels correlated significantly (p
Published:
1995-03
Title:
Vegetarian diet components, protein and blood pressure: which nutrients are important?
Authors:
Beilin, L. J.; Burke, V.
Abstract:
1. Evidence that vegetarian dietary patterns lower blood pressure (BP) comes from both population studies and randomized controlled trials in normotensive and hypertensive subjects. 2. The effect has been shown most clearly in those who keep to a strict lacto-ovo vegetarian diet characterized by a relatively low intake of saturated fat, a high polyunsaturated/saturated fat ratio, and a high intake of fruit, vegetables and other fibre containing products. Randomized controlled dietary trials suggest the effects are independent of dietary sodium, additive to that of calorie restriction, and not due to the absence of meat protein per se. Indeed, recent population studies suggest an inverse relationship between dietary protein and BP. 4. Dietary fats, fibre, potassium, magnesium and calcium do not independently seem to account for the effects. A possible role for complex carbohydrate in conjunction with the other dietary factors has yet to be fully explored.
Published:
1995-03
Title:
A vegetarian diet rich in soybean products compromises iron status in young students
Authors:
Shaw, N. S.; Chin, C. J.; Pan, W. H.
Abstract:
The iron status of young Chinese Buddhist vegetarians (23 men and 32 women) and nonvegetarian students (20 men and 39 women from a medical college) was investigated by dietary assessment of iron intake and hematological measurement of biochemical indices including hemoglobin, plasma iron, transferrin, transferrin saturation and plasma ferritin. A characteristic of the vegetarian diet in this study was the replacement of meat by soybean products. Results of the dietary assessment showed that the average iron density of the diets ranged from 1.9 to 2.2 mg/MJ, with no difference between the vegetarian and nonvegetarian diets. Daily iron intake was similar in both vegetarian and nonvegetarian men. However, iron intake was significantly higher in female vegetarians than nonvegetarians, averaging 104 and 78% of the RDA, respectively. Results of blood analysis showed that, for both sexes, the median plasma ferritin concentration of the vegetarians (male 47 micrograms/L and female 12 micrograms/L) was about half the level of the nonvegetarians (male 91 micrograms/L and female 27 micrograms/L). Occurrence and risk of iron deficiency are more prevalent in vegetarians. Correlation between plasma ferritin concentration and years of vegetarian practice in vegetarian men was marginally significant (r = -0.38, P = 0.077). We conclude that a vegetarian diet that is rich in soybean products and restricted in animal foods is limited in bioavailable iron and is not adequate for maintaining iron balance in men and women.
Published:
1995-02
Title:
Nutrient intakes and eating behavior scores of vegetarian and nonvegetarian women
Authors:
Janelle, K. C.; Barr, S. I.
Abstract:
OBJECTIVE: To compare nutrient intakes between vegetarians and nonvegetarians with similar health practices, and to assess relationships with eating behavior scores from the Three-Factor Eating Questionnaire. DESIGN: Survey. SETTING: Metropolitan area in western Canada. SUBJECTS: Subjects (n = 45) were participants in a study comparing subclinical menstrual disturbances between vegetarians and nonvegetarians. To be included, women had to be 20 to 40 years old, be weight stable with a body mass index (BMI; kg/m2) of 18 to 25, be a nonsmoker, exercise 7 hours a week or less, consume one alcoholic drink or less a day, and not be using oral contraceptives. Nonvegetarians (n = 22) ate red meat three times a week or more, and vegetarians (n = 23, 8 vegans and 15 lactovegetarians) had excluded all meat, fish, and poultry for 2 years or more. MAIN OUTCOME MEASURES: Nutrient intake assessed by three 3-day diet records; supplement use; body composition; and dietary restraint (conscious limitation of food intake), disinhibition, and hunger assessed by the Three-Factor Eating Questionnaire. STATISTICAL ANALYSES PERFORMED: Anthropometric variables, nutrient intakes, and eating behavior scores were compared between vegetarians and nonvegetarians using unpaired t tests, and among vegans, lactovegetarians, and nonvegetarians using one-way analysis of variance and Duncan's test. Supplement use was compared using chi 2 analysis. The Pearson correlation coefficient was used to evaluate relationships between variables. RESULTS: Diets of all women adhered closely to current nutrition recommendations. Vegetarians had lower protein and cholesterol intakes and higher percentage of energy as carbohydrate, ratio of polyunsaturated fat to saturated fat (P:S ratio), and fiber intake than nonvegetarians. Vegetarians had lower riboflavin, niacin, vitamin B-12, zinc, and sodium intakes and higher folate, vitamin C, and copper intakes. However, many differences were not apparent between the subgroup of lactovegetarians and nonvegetarians (their P:S ratios and carbohydrate, fiber, riboflavin, folate, vitamin C, and copper intakes were similar). In contrast, differences existed between the lactovegetarian and the vegan subgroups. Supplement use was similar between groups, except for greater vitamin C use by vegetarians. Vegetarians were leaner than nonvegetarians, had lower restraint scores, and had significant associations between restraint and BMI (r = .49; P < .05) and energy per kilogram body weight (r = -.60; P
Published:
1995-02
Title:
Vegetarian diet as a risk factor for tuberculosis in immigrant south London Asians
Authors:
Strachan, D. P.; Powell, K. J.; Thaker, A.; Millard, F. J.; Maxwell, J. D.
Abstract:
BACKGROUND: In a previous retrospective study of tuberculosis in south London among Asian immigrants from the Indian subcontinent Hindu Asians were found to have a significantly increased risk for tuberculosis compared with Muslims. This finding has been further investigated by examining the role of socioeconomic and lifestyle variables, including diet, as risk factors for tuberculosis in Asian immigrants from the Indian subcontinent resident in south London. METHODS: Using a case-control study technique Asian immigrants from the Indian subcontinent diagnosed with tuberculosis during the past 10 years and two Asian control groups (community and outpatient clinic controls) from the Indian subcontinent were investigated. Cases and community controls were approached by letter. A structured questionnaire concerning a range of demographic, migration, socioeconomic, dietary, and health topics was administered by a single trained interviewer to subjects (56 cases and 100 controls) who agreed to participate. RESULTS: The results confirmed earlier findings that Hindu Asians had an increased risk of tuberculosis compared with Muslims. However, further analysis revealed that religion had no independent influence after adjustment for vegetarianism (common among Hindu Asians). Unadjusted odds ratios for tuberculosis among vegetarians were 2.7 (95% CI 1.1 to 6.4) using community controls, and 4.3 (95% CI 1.8 to 10.4) using clinic controls. There was a trend of increasing risk of tuberculosis with decreasing frequency of meat or fish consumption. Lactovegetarians had an 8.5 fold risk (95% CI 1.6 to 45.4) compared with daily meat/fish eaters. Adjustment for a range of other socioeconomic, migration, and lifestyle variables made little difference to the relative risks derived using either community or clinic controls. CONCLUSIONS: These results indicate that a vegetarian diet is an independent risk factor for tuberculosis in immigrant Asians. The mechanism is unexplained. However, vitamin D deficiency, common among vegetarian Asians in south London, is known to affect immunological competence. Decreased immunocompetence associated with a vegetarian diet might result in increased mycobacterial reactivation among Asians from the Indian subcontinent.
Published:
1995-02
Title:
ACAT inhibitors decrease secretion of cholesteryl esters and apolipoprotein B by perfused livers of African green monkeys
Authors:
Carr, T. P.; Hamilton, R. L.; Rudel, L. L.
Abstract:
To test the hypothesis that newly synthesized cholesteryl esters are required for hepatic lipoprotein assembly and secretion, isolated livers of African green monkeys were perfused with medium containing an ACAT inhibitor. Three ACAT inhibitors with different structural and chemical properties were used: CI-976 (Parke-Davis), CP-113818 (Pfizer), or PD-138142-15 (Parke-Davis). Each compound produced variable effects on secretion of lipids and apolipoproteins. A significant decrease in the secretion rates of cholesteryl ester and apoB was common to all three inhibitors, indicating that fewer lipoprotein particles were secreted during ACAT inhibition. Triacylglycerol secretion was decreased in the presence of CP-113818 and PD-138142-15 but no decrease in triacylglycerol secretion was observed with CI-976. Particles secreted in the presence of CI-976 were enriched in triacylglycerol relative to apoB. Effects on secretion of other apolipoproteins (apoA-I, apoA-II, and apoE) were variable. When all data were combined, the percent inhibition of cholesteryl ester secretion and apoB secretion in the presence of ACAT inhibitors was positively correlated (r = 0.84), whereas a similar relationship was not observed between triacylglycerol and apoB. While the results demonstrate some lack of specificity for these ACAT inhibitors, the complimentary results using the three different ACAT inhibitors suggest that secretion of cholesteryl ester and apoB are coordinately regulated. The data suggest that newly synthesized cholesteryl esters may participate in and promote the assembly and secretion of hepatic apoB-containing lipoproteins. The availability of triacylglycerol during lipoprotein assembly, while also important, would appear to serve a role separate from that of cholesteryl ester.
Published:
1995-01
Title:
Consumption of diets containing raw soya beans (Glycine max), kidney beans (Phaseolus vulgaris), cowpeas (Vigna unguiculata) or lupin seeds (Lupinus angustifolius) by rats for up to 700 days: effects on body composition and organ weights
Authors:
Grant, G.; Dorward, P. M.; Buchan, W. C.; Armour, J. C.; Pusztai, A.
Abstract:
Feeding trials have been done with rats to assess the effects of long-term (700 d) consumption of diets based on raw cowpeas (Vigna unguiculata; moderate Bowman-Birk inhibitor content, low lectin content), lupin seeds (Lupinus angustifolius; low lectin and protease inhibitor content) or soya beans (Glycine max; high Kunitz inhibitor content, moderate Bowman-Birk inhibitor content, moderate lectin content) or diets containing low levels of raw kidney bean (Phaseolus vulgaris; high lectin content, low Bowman-Birk inhibitor content) on body weight and composition and organ weights. All the legume-based diets reduced feed conversion efficiency and growth rates during the initial 250 d. However, after 250 d the weight gains by rats given legume-based diets were similar to those of controls given the same daily feed intake. Long-term consumption of diets containing low levels of kidney bean significantly altered body composition of rats. The levels of lipid in the body were significantly reduced. As a result, carcasses of these rats contained a higher proportion of muscle/protein than did controls. Small-intestine relative weight was increased by short- and long-term consumption of the kidney-bean-based diet. However, the increase in relative pancreatic weight observed at 30 d did not persist long term. None of the other legume-based diets caused any significant changes in body composition. However, long-term exposure to a soya-bean- or cowpea-based diet induced an extensive increase in the relative and absolute weights of the pancreas and caused an increase in the incidence of macroscopic pancreatic nodules and possibly pancreatic neoplasia. Long-term consumption of the cowpea-, kidney-bean-, lupin-seed- or soya-bean-based diets by rats resulted in a significant increase in the relative weight of the caecum and colon.
Published:
1995-01
Title:
Effects of preslaughter muscle exercise on muscle metabolism and meat quality studied in anesthetized pigs of different halothane genotypes
Authors:
Klont, R. E.; Lambooy, E.
Abstract:
The influence of preslaughter muscle activity was studied on porcine muscle metabolism and meat quality, whereas other stress factors were minimized. Muscle exercise was stimulated by electrical pulses in anesthetized pigs of different halothane genotypes (NN, Nn, nn). A part of the LM and SM was stimulated during the last 15 min of a 45-min period of anesthesia. The contralateral part of each muscle was taken as a non-stimulated control. Antemortem blood and muscle biopsy samples were taken to study the muscle energy metabolism by measuring different metabolites. The same metabolites and certain meat quality characteristics were determined after slaughter. Stimulated muscle exercise led to lower (P < .01) antemortem glycogen and creatine phosphate concentrations and increased (P < .01) lactate and creatine values in pigs of all halothane genotypes. No difference was seen between the three halothane genotypes in the measured glycogen breakdown just before slaughter. Postmortem glycolysis differed between pigs of different halothane genotypes. This resulted in lower (P < .05) glycogen and creatine phosphate values and higher (P < .05) lactate and creatine concentrations for nn pigs than for NN pigs, with intermediate metabolite concentrations for Nn pigs. Water-holding capacity was lower (P < .05) in exercised muscles of NN and Nn pigs than in the muscles of controls. Meat color was only lighter (P
Published:
1995-01
Title:
Advanced Protein Glycosylation in Diabetes and Aging
Authors:
Brownlee, Michael, M.D
Abstract:
Products of advanced protein glycosylation (advanced glycation end products, or AGEs) accumulate in tissues as a function of time and sugar concentration. AGEs induce permanent abnormalities in extracellular matrix component function, stimulate cytokine and reactive oxygen species production through AGE-specific receptors, and modify intracellular proteins. Pharmacologic inhibition of AGE formation in long-term diabetic animals prevents diabetic retinopathy, nephropathy, neuropathy, and arterial abnormalities in animal models. Clinical trials in humans are currently in progress.
Published:
1995
Title:
American Food Habits in Historical Perspective
Authors:
McIntosh, Elaine N.
Abstract:
Published:
1995
Title:
Association between salt sensitivity and insulin concentrations in patients with hypertension
Authors:
Zavaroni, Ivana; Coruzzi, Paolo; Bonini, Luca; Mossini, Gian Luigi; Musiari, Luisa; Gasparini, Paola; Fantuzzi, Manuela; Reaven, Gerald M.
Abstract:
This study was performed in 28 patients with mild to moderate hypertension, classified as being either salt sensitive or salt resistant on the basis of the percent decrement in mean arterial blood pressure (MAP) seen 7 days after daily salt intake was decreased from 220 to 30 mmol/L. Ten patients had a percent decrease of MAP \textgreater10% and were defined as being salt sensitive. Salt resistance was defined as a percent decrease in MAP of \textless3% and eight patients satisfied this criterion. Both plasma glucose and insulin concentrations following a 75-g oral glucose challenge were significantly higher after the high-salt diet in the salt-sensitive patients. Furthermore, there were correlations of marginal statistical significance between the decrease in MAP after the low-salt diet and the plasma glucose (r = 0.32, P \textless .10) and insulin (r = 0.38, P \textless .06) responses to oral glucose. These data are consistent with the view that there is an association between resistance to insulin-mediated glucose disposal and salt sensitivity in patients with high blood pressure. © 1995 American Journal of Hypertension, Ltd.
Published:
1995
Title:
Biological Changes in Human Populations with Agriculture
Authors:
Larsen, Clark Spencer
Abstract:
Agriculture has long been regarded as an improvement in the human condition: Once Homo sapiens made the transition from foraging to farming in the Neolithic, health and nutrition improved, longevity increased, and work load declined. Recent study of archaeological human remains worldwide by biological anthropologists has shown this characterization of the shift from hunting and gathering to agriculture to be incorrect. Contrary to earlier models, the adoption of agriculture involved an overall decline in oral and general health. This decline is indicated by elevated prevalence of various skeletal and dental pathological conditions and alterations in skeletal and dental growth patterns in prehistoric farmers compared with foragers. In addition, changes in food composition and preparation technology contributed to craniofacial and dental alterations, and activity levels and mobility decline resulted in a general decrease in skeletal robusticity. These findings indicate that the shift from food collection to food production occasioned significant and widespread biological changes in human populations during the last 10,000 years.
Published:
1995
Title:
Broad spectrum diets in arid Australia
Authors:
Edwards, D.A.; O'Connell, J.F.
Abstract:
Published:
1995
Title:
CYP1A1 Messenger RNA Levels in Placental Tissue as a Biomarker of Environmental Exposure
Authors:
Whyatt, R.M.; Garte, S.J.; Cosma, G.; Bell, D.A.; Jedrychowski, W.; Wahrendorf, J.; Randall, M.C.; Cooper, T.B.; Ottman, R.; Tang, D.; Tsai, W.-Y.; Dickey, C.P.; Manchester, D.K.; Crofts, F.; Perera, F.P.
Abstract:
The human CYP1A1 gene codes for an inducible enzyme system involved in biotransformation of certain xenobiotics, including polycyclic aromatic hydrocarbons; some of the metabolites are carcinogenic and mutagenic. Effects of environmental exposures (smoking, air pollution, and diet) on CYP1A1 gene induction in placental tissue and the modulation of induction by the CYP1A1 Mspl RFLP were evaluated in two groups from Poland: 70 mother-child pairs from Krakow, a city with elevated air pollution; and 90 pairs from Limanowa, a less polluted area. Compared to placentas from nonsmoking women, CYP1A1 mRNA levels were significantly increased in placentas from current smokers (P < 0.001). Ex-smokers also had significantly higher placental mRNA levels, including women who quit smoking prior to pregnancy (P < 0.01). A marginal increase in CYP1A1 mRNA with environmental tobacco smoke exposure was evident. Within Krakow, there was an increase in CYP1A1 mRNA with ambient pollution at the place of residence for each woman, which was significant among women who were not employed away from the home (P < 0.05 controlling for smoking status, diet, and use of coal for heating). Significant increases in mRNA were associated with dietary consumption of smoked meat, cheese, and fish (P
Published:
1995
Title:
Changes in laboratory variables in rheumatoid arthritis patients during a trial of fasting and one-year vegetarian diet
Authors:
Kjeldsen-Kragh, J.; Mellbye, O. J.; Haugen, M.; Mollnes, T. E.; Hammer, H. B.; Sioud, M.; Førre, O.
Abstract:
We have previously reported that significant improvement may be obtained in rheumatoid arthritis patients by fasting followed by a vegetarian diet for one year. The present study was carried out to examine to what extent biochemical and immunological variables changed during the clinical trial of fasting and vegetarian diet. For the patients who were randomised to the vegetarian diet there was a significant decrease in platelet count, leukocyte count, calprotectin, total IgG, IgM rheumatoid factor (RF), C3-activation products, and the complement components C3 and C4 after one month of treatment. None of the measured parameters changed significantly during this period in the group of omnivores. The course of 14 of 15 measured variables favored the vegetarians compared with the omnivores, but the difference was only significant for leukocyte count, IgM RF, and the complement components C3 and C4. Most of the laboratory variables declined considerably in the vegetarians who improved according to clinical variables, indicating a substantial reduction in inflammatory activity. The leukocyte count, however, decreased in the vegetarians irrespective of the clinical results. Thus, the decline in leukocyte count may be attributed to vegetarian diet per se and not to the reduction in disease activity. The results of the present study are in accordance with the findings from the clinical trial, namely that dietary treatment can reduce the disease activity in some patients with rheumatoid arthritis.
Published:
1995
Title:
Chronological changes in stone artefact technology
Authors:
Morwood, M. J.; L'Oste-Brown, S.
Abstract:
Published:
1995
Title:
Comparative physiology of the vertebrate digestive system
Authors:
Stevens, Charles; Hume, Ian
Abstract:
Published:
1995
Title:
Comparison of the gastrointestinal anatomy, physiology, and biochemistry of humans and commonly used laboratory animals
Authors:
Kararli, Tugrul T.
Abstract:
In addition to metabolic differences, the anatomical, physiological, and biochemical differences in the gastrointestinal (G.I.) tract of the human and common laboratory animals can cause significant variation in drug absorption from the oral route. Among the physiological factors, pH, bile, pancreatic juice, and mucus and fluid volume and content can modify dissolution rates, solubility, transit times, and membrane transport of drug molecules. The microbial content of the G.I. tract can significantly affect the reductive metabolism and enterohepatic circulation of drugs and colonic delivery of formulations. The transit time of dosage forms can be significantly different between species due to different dimensions and propulsive activities of the G.I. tract. The lipid/protein composition of the enterocyte membrane along the G.I. tract can alter binding and passive, active, and carrier-mediated transport of drugs. The location and number of Peyer's patches can also be important in the absorption of large molecules and particulate matter. While small animals, rats, mice, guinea pigs, and rabbits, are most suitable for determining the mechanism of drug absorption and bioavailability values from powder or solution formulations, larger animals, dogs, pigs, and monkeys, are used to assess absorption from formulations. The understanding of physiological, anatomical, and biochemical differences between the G.I. tracts of different animal species can lead to the selection of the correct animal model to mimic the bioavailability of compounds in the human. This article reviews the anatomical, physiological, and biochemical differences between the G.I. tracts of humans and commonly used laboratory animals.
Published:
1995
Title:
Conclusions
Authors:
Morwood, M. J.; Hobbs, D. R.
Abstract:
Published:
1995
Title:
Decline of U#{14M9}edSi.cal Student Career Choice of Psychiatry and What to Do About It
Authors:
Sierles, S
Abstract:
Published:
1995
Title:
Directly toxic effects of plant chemicals which may occur in human and animal foods
Authors:
Seawright, A. A.
Abstract:
Pyrrolizidine alkaloids are among the most significant plant chemicals causing disease in animals and humans. After absorption from the gut, the compounds are converted to electrophilic pyrroles in the liver which, apart from causing damage to this organ, may escape to cause injury to extraheptic tissues such as the lungs, heart, and kidneys. A group of compounds more recently found to be associated with neurotoxicity are various polyhydroxyalkaloids which are able to interfere with polysaccharide metabolism. They are able to inhibit lysosomal monosaccharidases by virtue of their structural resemblance to the transition state of particular sugar molecules. The resulting lysosomal storage diseases have pathology identical to that of the respective congenital and heritable lysosomal storage diseases which occur in animals and humans. Consumption of cycad plants by cattle may cause a neurotoxicity characterised mainly by a posterior sensory ataxia. In recent years, cycads are considered to be a risk factor for a spectrum of progressive neuro degenerative diseases of humans in the Western Pacific region. The known toxins in the plant are the methylazoxymethanol glycosides which are hepatotoxic and carcinogenic, and the neurotoxic non-protein amino acid beta-methylaminoalanine. A plant carcinogen which can be of great abundance in the nutritional environment is the illudine norsesquiterpene glucoside ptaquiloside which is found in bracken fern. This is the only plant carcinogen which causes natural outbreaks of bladder and/or intestinal cancer in livestock. Many legumes contain phytooestrogens, notably isoflavones. Consumption of these compounds at high levels by sheep can cause extensive lesions of the genitalia of females and castrated males.(ABSTRACT TRUNCATED AT 250 WORDS)
Published:
1995
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