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1.
Serum selenium levels were determined cross-sectionally in 57 HIV-infected patients who were classified according to the Centers for Disease Control (CDC) 1993 classification system. Mean serum selenium levels were lower in CDC stage II (58.7±12.2 μg/L;p<0.01;n=18) and stage III (47.6±11.3 μg/L;p<0.01;n=19) HIV-infected patients, than in healthy subjects (80.6±9.6 μg/L;n=48) and stage I patients (73.6±16.5 μg/L;n=20). Serum selenium levels were positively correlated with CD4 count, CD4/8 ratio, hematocrit, and serum albumin (r=0.42;r=0.39;r=0.48; andr=0.45;p<0.01, respectively) and inversely with serum levels of thymidine kinase (r=−0.49;p<0.01;n=49) and β2-microglobulin (r=−0.46;p<0.001;n=49). In addition, serum selenium levels in 20 randomly selected AIDS-free individuals (CDC I:n=10; CDC II:n=10) were inversely correlated with serum concentrations of interleukin-8 (IL-8) and soluble tumor necrosis factor receptors (sTNFR) types I and II. There was no correlation with serum immuneglobulin A and total serum protein levels. The results show that the progressive deprivation of serum selenium in HIV-infection is associated with loss of CD4+-cells and with increased levels of markers of disease progression and inflammatory response.  相似文献   

2.
Obesity is among the main contributing factors in the etiology of essential hypertension (EHT). Leptin, the product of the ob gene, is expressed mainly in adipose tissue. We examined the relationship between two trace elements, zinc (Zn) and copper (Cu), and leptin in patients with EHT (n=35) and normotensive (NT) controls (n=50) because leptin as well as Zn and Cu were reported to be associated with the pathophysiology of EHT. Plasma leptin levels were determined with a commercial enzyme-linked immunosorbent assay (ELISA) kit. Atomic absorption spectrophotometry was utilized to determine plasma Zn and Cu levels. There was a negative correlation between leptin and Zn, and the Zn/Cu ratio (r=−0.359, p<0.05; r=0.361, p<0.05, respectively) in pooled subjects. When subjects were divided based on the presence or absence of hypertension, there was a negative correlation between leptin and Zn (r=−0.375, p<0.05) as well as leptin and Zn/Cu ratio (r=−0.398, p<0.05) in NT subjects. Similar trends were observed when leptin/BMI (body mass index) levels were utilized. There was no significant correlations between levels of Cu and leptin or leptin/BMI. In conclusion, in addition to high leptin levels, Zn and the Zn/Cu ratio were lower in patients with EHT compared to NT controls.  相似文献   

3.
This study evaluated levels of plasma zinc, copper, and leptin, body composition, and their relationship in nine elite female judo athletes under two different training conditions. Body composition and biochemical measurements (hematological indexes, plasma zinc, plasma copper, and plasma leptin) were analyzed 24 h after intense training and following a 5-d period without training (no-training). Plasma leptin and plasma zinc increased with no-training. Plasma zinc correlated negatively with percent fat mass (r=−0.62; r=0.05) and positively with plasma leptin (r=0.83; p=0.002) in the no-training condition Plasma copper did not change during the study and correlated positively with plasma leptin (r=0.66; p=0.05) and with percent fat mass (r=0.80; p=0.007) after training. Percent fat mass was associated negatively with plasma zinc (r=−0.62; p=0.05) in the no-training condition. Moreover percent fat mass was negatively associated with the Zn/Cu plasma ratio under both training conditions (r<−0.78, p<0.001). These results are consistent with the possible function of zinc as a lipid-mobilizing factor and of copper as a limiting factor in energy metabolism.  相似文献   

4.
5.
The concentrations of cadmium, lead, selenium, and zinc in blood and seminal plasma were determined in 76 Singapore males. Except for zinc, the concentrations were generally higher in blood than in seminal plasma (cadmium, 1.31 μg/L vs 0.61 μg/L; lead, 82.6 μg/L vs 12.4 μg/L, and selenium, 163.6 μg/L vs 71.5 μg/L). The mean concentration of zinc in seminal plasma was more than 30 times higher than in blood (202 mg/L vs 6.2 mg/L). Significant positive correlations were found between the concentrations in blood and seminal plasma for the two essential trace elements: selenium (r=0.45,p<0.001) and zinc (r=0.25,p<0.05). However, no relationships were found between the concentrations in blood and seminal plasma for two toxic metals (cadmium and lead). Significant inverse correlations were observed between Cd and Zn (r=−0.40,p<0.01), and Pb and Se (r=−0.32,p<0.05) in blood, whereas significant positive correlations were noted between Cd and Se (r=0.45,p<0.01), Cd and Zn (r=0.35,p<0.05), and Se and Zn (r=0.57,p<0.001) in seminal plasma. The physiological significance of these relationships are also discussed in this paper.  相似文献   

6.
Suppose that n individuals locate independently and randomly on a segment of line of finite length (habitat). Let the theoretical and observed ranges of the sites of the individuals on the segment be μn-1 and rn-1, respectively. Then, the degree of dispersion of the individual sites is measured by the ratio, Tn=nn-1n-1, as follows: A random spatial pattern for Ir−1=1 An aggregated spatial pattern for 0≤Ir<1 A uniform spatial pattern for (n+1)/(n−1)≥Ir>1. Another method was derived. Let the probability that an observed range is less than rn−1 be Ip, under the hypothesis of a Beta distribution. Then indicates A random spatial pattern for Ip=1/2 An aggregated spatial pattern for Ip<1/2 A uniform spatial pattern for Ip>1/2. The first index can be used for comparing populations having the same number of individuals, whereas the second one can be used for comparing populations with different numbers of individuals.  相似文献   

7.
Length–weight relationships and condition factors of wild, cultured, and cultured loose‐shell affected Penaeus monodon (2,609 specimens total) were studied from March to August 2007. The regression equation for healthy cultured shrimps was log W = ?1.811 + 2.721 log L (r2 = 0.71); log W = ?1.444 + 2.485 log L (r2 = 0.91) for wild shrimps; and log W = ?1.112 + 2.237 log L (r2 = 0.92) for loose‐shell affected shrimps. All shrimps showed negative allometric growth, although ancova indicated significant differences (P < 0.05) among them. This study presents the first known reference dealing with LWRs and condition factors of cultured, wild and loose‐shell affected P. monodon.  相似文献   

8.
This study describes the reproductive biology of the Chinese minnow Hemiculterella sauvagei. The length‐weight relationship, sex ratio, spawning season, size at first maturity, and fecundity were analyzed based on 685 specimens collected from the Chishui River between July 2011 and July 2012. The relationship between standard length (SL) and body weight (BW) were estimated as BW = 2.14 × 10?4 × SL2.801 (R2 = 0.839; N = 413; P < 0.05) for females and BW = 1.31 × 10?4 × SL3.001 (R= 0.868; N = 272; P < 0.05) for males. The female to male sex ratio, 1.52 : 1, differed significantly from a 1 : 1 ratio. Females predominated in standard lengths >12 cm. Analyses of the monthly variation in the gonadosomatic index (GSI), the monthly proportions of macroscopic gonadal maturity, and the size distribution of oocytes consistently suggested a prolonged spawning season of H. sauvagei from March to August, with a peak from April to May. Logistic curves describing the relationship between proportion of maturity (Pr) at each length interval and standard length were estimated as Pr = 1/(1 + e26.867–0.306SL) (R= 0.999; N = 413; P < 0.05) for females and Pr = 1/(1 + e10.522–0.142SL) (R= 0.999; N = 272; P < 0.05) for males. Size at first maturity was estimated as 7.4 cm for males and 8.8 cm SL for females. Absolute fecundity varied from 563 to 5052, with a mean of 2413 ± 874 oocytes per ovary. The relative fecundity was estimated to be 41–299, with a mean of 171 ± 55 oocytes per ovary. The present study provides useful information for fishery management and resources conservation.  相似文献   

9.
Species are often controlled by biotic factors such as competition at the warm edge of their distribution range. Disturbances at the treeline, disrupting competitive dominance, may thus enable alpine species to utilize lower altitudes. We searched for evidence for range expansion in grazed, fire‐managed Ethiopian subalpine Erica heathlands across a 25‐year chronosequence. We examined vascular plant composition in 48 plots (5 × 5 m) across an altitudinal range of 3,465–3,711 m.a.s.l. and analyzed how community composition changed in relation to increasing competition over time (using a Shade index based on Erica shrub height and cover) and altitude. Species‘ habitats and altitudinal ranges were derived from literature. Time since fire explained more variation (r2 = .41) in species composition than altitude did (r2 = .32) in an NMDS analysis. Community‐weighted altitudinal optima for species in a plot decreased strongly with increasing shade (GLM, Standardized Regression Coefficient SRC = ?.41, p = .003), but increased only weakly with altitude (SRC = .26, p = .054). In other words, young stands were dominated by species with higher altitudinal optima than old stands. Forest species richness increased with Log Shade index (SRC = .12, p = .008), but was unaffected by altitude (SRC = ?.07, p = .13). However, richness of alpine and heathland species was not highest in plots with lowest Shade index, but displayed a unimodal pattern with an initial increase, followed by a decrease when shading increased (altitude was not significant). Our results indicate that disturbance from the traditional patch burning increases the available habitat for less competitive high‐altitude plants and prevents tree line ascent. Therefore, maintaining, but regulating, the traditional land use increases the Afro‐alpine flora's resilience to global warming. However, this system is threatened by a new REDD+ program attempting to increase carbon storage via fire suppression. This study highlights the importance of understanding traditional management regimes for biodiversity conservation in cultural landscapes in an era of global change.  相似文献   

10.
Lactose percentage (LP) in milk is currently determined in most herd-testing schemes, and globally, it is usually routinely recorded in the framework of the official milk recording procedures. However, few studies have investigated the phenotypic and genetic variability of this component. Data used in the present paper consisted of 59 811 test-day records from 4355 Holstein cows in 266 herds. Heritabilities of LP and lactose yield (LY) were estimated through single-trait repeatability animal models, whereas genetic and phenotypic correlations of LP and LY with milk composition and production traits, somatic cell score and milk freezing point were estimated using bivariate models. Fixed effects included in the analyses were herd-test-date, season of calving, parity, stage of lactation and the interaction between parity and stage of lactation. Random effects were animal additive genetic, within and across lactation permanent environment and the residual. Lactation curves of LP and LY increased from parturition to the peak of lactation and decreased thereafter, mirroring the typical curve of milk yield. Lactose percentage was greater in first- than later-parity cows. Heritabilities of LP and LY were 0.43±0.03 and 0.14±0.02, respectively, and LP and protein percentage were the most repeatable traits. Genetic correlations (ra) of LP with somatic cell score, LY and milk freezing point were −0.22±0.08, 0.28±0.08 and −0.46±0.05, respectively. Genetic relationships of LY with milk yield (ra=0.97±0.00), fat percentage (ra=−0.71±0.06), protein percentage (ra=−0.57±0.06) and protein yield (ra=0.64±0.06) were moderate to strong. Results suggest that milk LP could be considered in breeding strategies to accelerate the gain of correlated low heritable traits. Further research is needed to evaluate the feasibility of including LP in the selection index of Italian Holstein population to address country-specific needs and market demands.  相似文献   

11.
Selenium concentration in blood and hair of holstein dairy cows   总被引:1,自引:0,他引:1  
Four-hundred Holstein cows in 40 dairy farms in north Greece were included in this study, and blood (n=400), black hair (n=400), white hair (n=40), and feed (n=40) samples were obtained. Although the feeding regime in these farms was similar, the selenium content of feeds was variable. The Se content of concentrate feeds was 0.104±0.086 mg/kg dry matter (DM), and of silage, it was 0.025±0.018 mg/kg. A significantly positive correlation was found between the Se concentration in black hair and the Se concentration in blood (r 2=0.610, p<0.001), the Se concentration in white hair and the Se concentration in blood (r 2=0.770, p<0.001), and the Se concentration in white hair and the Se concentration in black hair (r 2=0.921, p<0.001). The Se concentration in white hair was significantly smaller than that in black hair (p<0.001).  相似文献   

12.
Background. Cyclooxygenase (COX)‐2 induced by Helicobacter pylori is thought to enhance gastric carcinogenesis by affecting the maintenance of epithelial homeostasis. Materials and Methods. Gastric biopsies from 160 subjects, 97 with nonulcer dyspepsia (47 H. pylori negative, 50 H. pylori positive) and 63 with gastric cancer were examined immunohistochemically for COX‐2 expression, cell proliferation and apoptotic indices. Results. COX‐2 expression in corpus was significantly higher in H. pylori positive than in negative non‐ulcer dyspepsia (NUD) (p < .05). Regardless of site, gastric cancer subjects had higher COX‐2 expression in both antrum and corpus compared with H. pylori negative and positive NUD (p < .005). Proliferation was higher in cancer and H. pylori positive than in negative NUD (p < .0001). Moreover, cancer had enhanced proliferation than H. pylori positive NUD in corpus greater (p = .0454) and antrum lesser (p = .0215) curvatures. Apoptosis was higher in H. pylori positive than in negative NUD (p < .05). However, both had a higher index than the cancer subjects (p < .0001). Apoptosis : proliferation ratio was higher in corpus of H. pylori negative than in positive NUD in greater (p = .0122) and lesser (p = .0009) curvatures. However, both had a higher A:P ratio than cancer cases (p = .0001). A negative correlation between COX‐2 expression and A:P ratio was found in corpus greater (r = –.176, p= .0437) and lesser (r = –.188, p= .0312) curvatures. Conclusion. The expression of COX‐2 is associated with disruption in gastric epithelial kinetics and hence may play a role in gastric carcinogenesis.  相似文献   

13.
The aim of the present study is to evaluate the status of plasma essential trace elements selenium (Se), zinc (Zn), copper (Cu), and iron (Fe) concentrations and their related acute-phase proteins, ceruloplasmin (Cp), ferritin, transferrin (Tf), and albumin levels in patients with vivax malaria. Plasma Cu and Zn concentrations were determined by atomic absorption spectrometry (AAS). Se concentrations were determined by graphite furnace AAS. Fe, Cp, Tf, and albumin levels were determined by colorimetric methods. Plasma Se, Fe, and albumin levels were found to be significantly lower (p<0.01, p<0.001, and p<0.05, respectively) and Cu, Cp, and ferritin levels and Cu/Zn ratios were significantly higher (p<0.001, p<0.001, p<0.001, and p<0.05, respectively) in patients when compared with those of healthy subjects. Plasma, Tf, and Zn levels were not found to be significantly different (p>0.05) in patients and controls. There were positive important correlations between Cu and Cp (r=0.908, p<0.001), Zn and albumin (r=0.633, p<0.001), and negative correlations between Fe and ferritin content (r=−0.521, p<0.05) and Fe and Tf (r=−0.616, p<0.01) in the patients group. Our findings demonstrated that plasma essential trace elements Se, Cu, and Fe change, but these changes might be dependent on acute-phase proteins, which were regulated as a part of defense strategies of the organism, induced by hormonelike substances.  相似文献   

14.
The purpose of this study was to compare plasma leptin, plasma zinc, and plasma copper levels and their relationship in trained female and male judo athletes (n = 10 women; n = 8 men). Blood samples were obtained 24 h after training to measure plasma zinc, copper, and leptin levels. Subjects presented similar values to age (22 ± 2 years old), body mass index (24 ± 1 kg/m2), plasma zinc (17.2 ± 2 μmol/L), copper (12.5 ± 2 μmol/L), and leptin (5.6 ± 1.3 μg/L). However, height, total body mass, lean mass, fat mass, and sum of ten-skinfold thickness were higher in male than female. Plasma leptin was associated with sum of ten skinfolds in male (r = 0.91; p < 0.001) and female athletes (r = 0.84; p < 0.003). Plasma zinc was associated with leptin in males (r = 0.82; p < 0.05) while copper was associated with plasma leptin in females (r = 0.66; p < 0.05). Our results suggest that young judo athletes lost sex-related differences in leptin levels. Plasma zinc, plasma copper, and energy homeostasis may be involved in regulation of plasma leptin.  相似文献   

15.
We have separated and quantified two new minor hemoglobins named HbA1d3a and HbA1d3b. The level of HbA1d3a was significantly higher in uremic than in non-uremic patients (3.00 ± 0.50% vs. 1.28 ± 0.26% of total hemoglobin). It correlated well with carbamylated hemoglobin (r=0.80, n=81, p<0.002) and with plasma urea concentration (r=0.78, n=81, p<0.002). These data and the electrospray ionization mass spectrometric analysis provide strong evidence that HbA1d3a is an α-chain modified by carbamylation. The HbA1d3b level in the diabetic patients was found to be 1.6-fold that in non-diabetic subjects (3.00 ± 0.49 vs. 1.90 ± 0.33). This was attributed to HbA1d3 modified by glycation. Indeed HbA1d3b correlated significantly with HbA1c (r=0.71, p<0.002) and with serum glucose level (r=0.62, p<0.002). These two new minor hemoglobins may serve as complements for the objective assessment of averagd long-term uremia and glycemia in uremic and diabetic patients.  相似文献   

16.
Nitric oxide (NO) participates in the pathogenesis of inflammatory reactions in many autoimmune diseases such as rheumatoid arthritis (RA). There is a reciprocal pathway between arginase and nitric oxide synthese (NOS) for NO production, and Mn is required for arginase activity and stability. To investigate whether NO production related with the arginine-nitric oxide pathway in patients with RA, we measured synovial fluid and plasma nitrite (NOx) levels, arginase activities, and its cofactor manganese (Mn) concentrations in 21 RA patients and 13 healthy control subjects. Plasma albumin levels were measured as an index of nutritional status. NOx levels were determined after the reduction of nitrates to nitrites using the Griess reaction. Whereas, synovial fluid arginase activities and Mn levels were found to be significantly lower (p<0.001, p<0.001, respectively), plasma arginase activities and Mn levels were similar in patients with RA when compared to the control subjects. Plasma and synovial fluid NO levels were similar in patients with RA and in healthy subjects (p>0.05, p>0.05, respectively). There were significantly positive correlations between synovial fluid and plasma arginase activities vs Mn content (r=0.543, p=0.011; r=0.516, p=0.017, respectively) and significantly negative correlations between synovial fluid and plasma NO levels vs arginase activities (r=−0.497, p=0.022; r=−0.508, p=0.019 respectively) in the patients group. Our results indicate that the lower concentration of synovial fluid Mn could cause lower arginase activity and this could also upregulate NO production by increasing L-arginine content in patients with RA.  相似文献   

17.
R. RIDING 《Geobiology》2006,4(4):299-316
Photosynthetic uptake of inorganic carbon can raise the pH adjacent to cyanobacterial cells, promoting CaCO3 precipitation. This effect is enhanced by CO2 concentrating mechanisms that actively transport into cells for carbon fixation. CO2 concentrating mechanisms presumably developed in response to atmospheric decrease in CO2 and increase in O2 over geological timescales. In present‐day cyanobacteria, CO2 concentrating mechanisms are induced when the atmospheric partial pressure of CO2 (pCO2) falls below ~0.4%. Reduction in pCO2 during the Proterozoic may have had two successive effects on cyanobacterial calcification. First, fall in pCO2 below ~1% (33 times present atmospheric level, PAL) resulted in lower dissolved inorganic carbon (DIC) concentrations that reduced pH buffering sufficiently for isolated CaCO3 crystals to begin to nucleate adjacent to cyanobacterial cells. As a result, blooms of planktic cyanobacteria induced precipitated ‘whitings’ of carbonate mud in the water column whose sedimentary accumulation began to dominate carbonate platforms ~1400–1300 Ma. Second, fall in pCO2 below ~0.4% (10 PAL) induced CO2‐concentrating mechanisms that further increased pH rise adjacent to cells and promoted in vivo cyanobacterial sheath calcification. Crossing of this second threshold is indicated in the fossil record by the appearance of Girvanella 750–700 Ma. Coeval acquisition of CO2 concentrating mechanisms by planktic cyanobacteria further stimulated whiting production. These inferences, that pCO2 fell below ~1%~1400–1300 Ma and below ~0.4% 750–700 Ma, are consistent with empirical and modelled palaeo‐atmosphere estimates. Development of CO2 concentrating mechanisms was probably temporarily slowed by global cooling ~700–570 Ma that favoured diffusive entry of CO2 into cells. Lower levels of temperature and DIC at this time would have reduced seawater carbonate saturation state, also hindering cyanobacterial calcification. It is suggested that as Earth emerged from ‘Snowball’ glaciations in the late Neoproterozoic, global warming and O2 rise reactivated the development of CO2 concentrating mechanisms. At the same time, rising levels of temperature, calcium ions and DIC increased seawater carbonate saturation state, stimulating widespread cyanobacterial in vivo sheath calcification in the Early Cambrian. This biocalcification event promoted rapid widespread development of calcified cyanobacterial reefs and transformed benthic microbial carbonate fabrics.  相似文献   

18.
In this study, results are reported from the analyses of vastus lateralis muscle biopsy samples obtained from a subset (n = 90) of 125 previously phenotyped, highly active male and female cyclists aged 55–79 years in regard to age. We then subsequently attempted to uncover associations between the findings in muscle and in vivo physiological functions. Muscle fibre type and composition (ATPase histochemistry), size (morphometry), capillary density (immunohistochemistry) and mitochondrial protein content (Western blot) in relation to age were determined in the biopsy specimens. Aside from an age‐related change in capillary density in males (r = ?.299; p = .02), no other parameter measured in the muscle samples showed an association with age. However, in males type I fibres and capillarity (p < .05) were significantly associated with training volume, maximal oxygen uptake, oxygen uptake kinetics and ventilatory threshold. In females, the only association observed was between capillarity and training volume (p < .05). In males, both type II fibre proportion and area (p < .05) were associated with peak power during sprint cycling and with maximal rate of torque development during a maximal voluntary isometric contraction. Mitochondrial protein content was not associated with any cardiorespiratory parameter in either males or females (p > .05). We conclude in this highly active cohort, selected to mitigate most of the effects of inactivity, that there is little evidence of age‐related changes in the properties of VL muscle across the age range studied. By contrast, some of these muscle characteristics were correlated with in vivo physiological indices.  相似文献   

19.
The study describes the concentrations of zinc, magnesium, copper, iron, and biochemical markers of seminal vesicle and prostate in seminal plasma of different categories of infertile men. The zinc level in oligasthenospermic subjects was significantly higher than in azoospermic, asthenospermic, and oligospermic subjects. The γ-glutamyl transpeptidase activity in both oligoasthenospermic and azoospermic subjects were significantly lower than in asthenospermic and oligospermic individuals. There was no significant difference in iron, copper, and magnesium levels and acid phosphatase activity among the different infertile categories. A positive correlation between zinc and acid phosphatase (r=0.84, r=0.73; p<0.05), and between copper and fructose (r=0.81, r=0.72; p<0.05) was observed in oligoasthenospermic and azoospermic men, respectively. On the basis of our results, it may be postulated that there is a direct effect of the trace elements zinc and copper on acid phosphatase and fructose, respectively, in oligoasthenospermic and azoospermic subjects.  相似文献   

20.
This study compared several maternal risk factors of low birth weight (LBW) between 204 normal birth weight (NBW) and 133 LBW newborns from Kolkata, India. Based on their birth weight (BW), newborns were classified as LBW (BW < 2.5 kg) and NBW (BW ≥ 2.5 kg). Results revealed that means for maternal age (MA, p < 0.05), gestational age (GA, p < 0.01), hemoglobin (Hb) concentration (p < 0.05), and per capita daily income (PCDI, p < 0.05) were significantly higher among mothers of NBW. Correlation analyses revealed that MA (r = 0.119, p < 0.05), GA (r = 0.583, p < 0.01), PCDI (r = 0.118, p < 0.05), and Hb (r = 0.138, p < 0.05) were significantly positively correlated with BW; PCDI was also significantly positively correlated (r = 0.142, p < 0.01) with Hb. Stepwise regression analyses with BW as the dependent variable revealed that GA (t = 7.915, p < 0.001) and Hb (t = 2.057, p < 0.05) were the most important predictive variables. The effect of Hb, independent of GA, was statistically significant (change in F = 4.231, p < 0.05). Because GA is not modifiable in pregnant women, there is a need to increase Hb levels among pregnant mothers. Most importantly, appropriately targeted preventive strategies, including iron supplementation, need to be implemented for health promotion.  相似文献   

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