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151.
Mammals that hibernate must rely on endogenous lipid reserves to survive over winter. This study was conducted to compare the difference in serum fatty acid composition, dietary intake, and apparent digestibility in the Vancouver Island marmot (N = 6) fed the Metro Zoo lagomorph diet supplemented with α‐linolenic acid [C(18:3) n‐3 (α‐LA)]. The experiment was designed as a 3 × 3 Latin square with three 17‐day collection periods. The test diets contained 12.16, 14.85, and 17.05% α‐LA as a percentage of fatty acids in the diet supplied through the addition of flaxseed oil (~53% α‐LA). Across treatments, dry matter intake (g/d), dry matter digestibility, apparent fat digestibility, and apparent neutral detergent fiber digestibility did not differ significantly (P > 0.05). There were no significant differences in serum α‐LA concentration between the three levels of α‐LA supplementation. However, this supplementation did elevate serum α‐LA, eicosapentaenoic acid [C20:5 (n‐3)], and docosahexaenoic acid [C22:6 (n‐3)] levels compared with feeding the basal zoo lagomorph diet (P < 0.05). Thus, supplementation of the basal zoo lagomorph diet with α‐LA elevated the serum levels of essential fatty acids in the Vancouver Island marmot. Zoo Biol 20:251–259, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
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Background

Highly active antiretroviral therapy (HAART) can cause side effects in HIV patients, as the metabolic syndrome. Early identification of risk for development of cardiovascular diseases using available reliable and practical methods is fundamental. On this basis, the aim of this study was to compare the effectiveness of anthropometric indicators to identify metabolic syndrome in HIV patients on HAART.

Methods

It is a cross-sectional study. A number of 280 stable HIV patients were studied. It measured weight, height, waist circumference (WC), hip circumference (HP), thigh circumference (TC) and calculated body mass index (BMI), body adiposity index (BAI), waist to hip ratio (WHR) and waist to thigh ratio (WTR). There was also a performance of biochemical tests of lipid profile and fasting glucose. Systemic blood pressure was measured. The criteria proposed by the National Cholesterol Education Program III (NCEP-ATP III) to metabolic syndrome classification was used. Individuals were divided in groups with or without metabolic alterations and their anthropometric indicators were compared. Receiver operating characteristic (ROC) curves were designed for each anthropometric indicator using the metabolic syndrome classification to identify sensitivity and specificity.

Results

WC was a good tool to identify each metabolic disorder separately: total cholesterol (only females, p<0.05), triglycerides (only males, p<0.001), HDL cholesterol (p<0.05), LDL cholesterol (p<005) and fasting glycemic (p<005). WC also showed the best performance to identify metabolic syndrome in both genders (areas under the curve (AUCs): 0.79 and 0.76 for male and female, respectively), while BAI proved to be an inadequate indicator (AUCs: 0.63 and 0.67 for males and females), respectively, in this population.

Conclusions

The central adiposity measure (WC) had the best performance to identify metabolic syndrome, and it is a convenient, cheap and reliable tool that can be used in clinical practice routinely to prevent cardiovascular complications in HIV patients.  相似文献   
154.
We report here our analysis of HLA class II alleles in 180 Caucasian nuclear families with at least two children with insulin-dependent diabetes mellitus (IDDM). DRB1, DQA1, DQB1, and DPB1 genotypes were determined with PCR/sequence-specific oligonucleotide probe typing methods. The data allowed unambiguous determination of four-locus haplotypes in all but three of the families. Consistent with other studies, our data indicate an increase in DR3/DR4, DR3/DR3, and DR4/DR4 genotypes in patients compared to controls. In addition, we found an increase in DR1/DR4, DR1/DR3, and DR4/DR8 genotypes. While the frequency of DQB1*0302 on DR4 haplotypes is dramatically increased in DR3/DR4 patients, DR4 haplotypes in DR1/DR4 patients exhibit frequencies of DQB1*0302 and DQB1*0301 more closely resembling those in control populations. The protective effect of DR2 is evident in this data set and is limited to the common DRB1*1501-DQB1*0602 haplotype. Most DR2+ patients carry the less common DR2 haplotype DRB1*1601-DQB1*0502, which is not decreased in patients relative to controls. DPB1 also appears to play a role in disease susceptibility. DPB1*0301 is increased in patients (P < .001) and may contribute to the disease risk of a number of different DR-DQ haplotypes. DPB1*0101, found almost exclusively on DR3 haplotypes in patients, is slightly increased, and maternal transmissions of DRB1*0301-DPB1*0101 haplotypes to affected children occur twice as frequently as do paternal transmissions. Transmissions of DR3 haplotypes carrying other DPB1 alleles occur at approximately equal maternal and paternal frequencies. The complex, multigenic nature of HLA class II-associated IDDM susceptibility is evident from these data.  相似文献   
155.
Endogenous digoxin-like immunoreactive factors (DLIF) are present in serum and tissues of humans and animals. To date, a tissue source for these factors has not been rigorously defined nor have these factors been isolated to identifiable homogeneity. In this study, we define the distribution of DLIF in mammalian tissues, demonstrate the adrenal cortex to be the principal source of this factor in bovine, and isolate DLIF to chromatographic homogeneity using high performance liquid chromatography (HPLC). DLIF concentrations in tissue extracts from rats measured as follows: adrenal glands, 44.3; serum, 6.3; liver, 5.2; kidney, 1.2; heart, brain, or lungs, less than 1.4 ng of digoxin-equivalent per g of protein. Human tissues showed similar results. In dogs, the ratio of the DLIF concentration in lumbar vein serum to that in infrarenal inferior vena cava serum was 3.3 +/- 0.4 (mean +/- S.E., n = 4). Bovine adrenal cortex contained 7 times more DLIF per g of tissue than the adrenal medulla. 70 +/- 4% (n = 7) of the total bovine cortical DLIF activity (6,159 pg of digoxin-equivalent) applied to a reverse phase HPLC column eluted as one definitive fraction. 60% of the digoxin-like immunoreactivity extracted from bovine serum also co-eluted with DLIF from adrenal. None of the 14 steroid molecules or 7 cardiac glycoside congeners co-eluted with the major DLIF activity. Our data indicate that 947 pmol of DLIF is equivalent to 1 pmol of digoxin-equivalent immunoreactivity. Preliminary mass spectral analysis suggests that purified DLIF has a molecular mass of 780 daltons comprised of one 390-dalton aglycone component plus several sugar moieties. This study establishes a definitive link between DLIF in serum and the adrenal cortex as a source tissue. We also demonstrate a method for purifying DLIF to chromatographic homogeneity with an extraction capacity of 1.2 nmol of DLIF per g of adrenal cortex.  相似文献   
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Arboreal termites (Nasutitermes spp.) and stomach contents from tamanduas (Tamandua tetradactyla) were collected in central Venezuela during the mid part of the dry season (March) of 1993 and 1994. Nutritional analyses were performed on each caste (workers n = 3), soldiers (n = 5), and alates [n = (1]), on mixed caste samples (n = 1), and on stomach contents from live (n = 5) and roadkill (n = 5) tamanduas. The chemical analysis, expressed on a dry matter (DM) basis, of termite workers, which constituted the majority of the nest populations, showed the highest crude protein (CP) (67%) and the lowest DM (25%) and fat (2%) values. Ash content varied from a low of 4% in alates to a high of 7% in soldiers. The alates contained substantially higher DM (41%) and fat (40%), which was reflected in a higher caloric value (6.88 kcal/g) (gross energy) [GE], and relatively less CP (49%). Among the macrominerals, potassium (K) was consistently the highest, with an overall mean value of 0.54%, while the calcium (Ca) and phosphorus (P) levels showed overall means of 0.26% and 0.67%, respectively. Iron (Fe) was the highest among the trace minerals but highly variable (soldiers, 1,000 ppm; alates, 246 ppm; workers, 394 ppm). Differences in the concentrations of vitamin A and E were found among termites castes, with soldiers showing the highest values (20 and 85 μg/g for retinol and α-tocopherol, respectively). Acid detergent fiber (ADF) was lower in the alates (13%) and workers (27%) compared to the soldiers (35%). Alates' fat was more saturated (39%), while soldiers and workers had a much higher polyunsaturated fatty acid (PUFA) concentration. In general, similar nutrient profiles were found between the tamandua stomach contents and the overall mean composition of Nasutitermes spp. However, stomach contents had much higher ADF, ash, and Fe concentrations (31%, 14%, and 2,748 ppm) than termites (25%, 5%, and 652 ppm) but lower CP, fat, GE, and Ca values (51%, 11%, 4.58 kcal/g, and 0.11% vs. 58%, 15%, 6.01 kcal/g, and 0.26% in termites). The relatively low concentrations of Ca in both stomach contents and termites may be indicative of a low requirement in Myrmecophaga compared to other mammalian species. Diets consumed by free-ranging tamanduas contained on a DM basis 51% CP, 11% fat, 14% ash, 31% ADF, 4.58 kcal/g GE, 0.11% Ca, 0.41% P, 2.52 μg/g retinol, and 44.3 μg/g α-tocopherol. Duplication of these nutrient profiles might greatly benefit captive health and reproduction of this species. © 1996 Wiley-Liss, Inc.  相似文献   
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