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1.
Although a 40 % absorption of a standard reference dose corresponds to iron (Fe) absorption in borderline Fe-deficient subjects, this percentage is currently applied to all subjects independent of Fe status: (a) to assess the use of the 40 % of Fe absorption of the reference dose (FeRD%) for subjects with iron-depleted stores (IDS), normal Fe status (NIS), Fe deficiency without anemia (IDWA), and Fe deficiency anemia (IDA) and (b) to explore relationships between Fe status biomarkers and FeRD%. Six hundred forty-six participants (582 women and 64 men) were selected from multiple Fe bioavailability studies and classified into four groups based on Fe status: NIS, IDS, IDWA, and IDA. All men were classified as normal. The absorption from FeRD% was calculated in each group and correlated with Fe status biomarkers. (a) Women with IDS absorbed 40 (18.9–84.7)?% of the reference dose; (b) for male subjects with NIS, the absorption of the reference dose was 19 (9.8–36.1)?%, while for females, absorption was observed as to be 34 (16.7–68.6)%. In the case of subjects with IDWA, a 43 (19.7–92.5)?% absorption was observed, while subjects with IDA demonstrated 67 (45.2–98.6)?% absorption. Serum ferritin (SF) had the strongest inverse correlation with FeRD% (r?=??0.41, p?<?0.001). A transferrin saturation (TS) <15 % increases the probability that the FeRD% will be highly elevated (OR, 5.05; 95 % CI, 2.73, 9.31; p?<?0.001). A 40 % absorption as reference dose is only appropriate to assess Fe absorption in subjects with IDS and IDWA. SF had an inverse correlation with FeRD%, and TS increases the probability that the FeRD% will be elevated by over fivefold.  相似文献   

2.
The aim of the study was to determine the association between vitamin D and attention deficit hyperactivity disorder (ADHD), and difference in the level of vitamin D in ADHD children and control. This a case–control study carried out in school health and primary health care clinics. A total of 1,331 children and adolescents who were diagnosed with ADHD based on clinical criteria and standardized questionnaires were enrolled in this study and were matched with 1,331 controls, aged 5–18 years old. Data on body mass index (BMI), clinical biochemistry variables including serum 25-hydroxyvitamin D were collected. The study found significant association between ADHD and vitamin D deficiency after adjusting for BMI and sex (adj. OR 1.54; 95 % CI 1.32–1.81; P < 0.001). Majority of the ADHD children were in the age group 5–10 years (40.7 %), followed by 11–13 years (38.4 %). The proportion of BMI <85th percentile was significantly over represented in ADHD group as compared to healthy control (87.8 vs. 83 %; P < 0.001, respectively), while on the other hand, BMI >95th percentile was over represented in the control than ADHD group (7.6 vs. 4.6 %; P < 0.001, respectively). Mean values of vitamin D (ng/mL) were significantly lower in ADHD children (16.6 ± 7.8) than in healthy children (23.5 ± 9.0) (P < 0.001). There was significant correlation between vitamin D deficiency and age (r = ?0.191, P = 0.001); calcium (r = 0.272, P = 0.001); phosphorous (r = 0.284, P = 0.001); magnesium (r = 0.292, P = 0.001); and BMI (r = 0.498, P = 0.001) in ADHD children. The vitamin D deficiency was higher in ADHD children compared to healthy children.  相似文献   

3.
There is an increasing interest for the role of liver enzymes as predictors of non-liver-related morbidity and mortality. The American Heart Association (AHA) described the ideal cardiovascular health concept as a score of seven cardiovascular health behaviors and factors that can be used to monitor and predict ideal cardiovascular health over time. This study aimed to examine the association of the ideal cardiovascular health (ICH), as defined by the AHA, with liver enzyme levels in European adolescents. A total of 637 adolescents (54.6% females), aged 14.6 ± 1.2 years from nine European countries participated in this cross-sectional study. Blood levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase were measured and the AST/ALT ratio calculated. Ideal cardiovascular health was defined as meeting ideal levels of the following components: four behaviors (smoking, body mass index, physical activity, and diet) and three factors (total cholesterol, blood pressure, and glucose). A higher number of ideal cardiovascular health behaviors, factors, and ideal cardiovascular health index were associated with lower ALT (P < 0.05, P < 0.001, and P < 0.001, respectively) and gamma-glutamyltransferase (P < 0.001, P < 0.01, and P < 0.001, respectively) levels. Similarly, a higher number of ideal cardiovascular health behaviors (P < 0.01), factors (P < 0.01), and ideal cardiovascular health index (P < 0.001) were associated with a higher aspartate aminotransferase to alanine aminotransferase ratio. These findings reinforce the usefulness of the ICH index as an instrument to identify target individuals and promote cardiovascular health in adolescents, and it also extends these observations to the liver manifestation of the metabolic syndrome.  相似文献   

4.
C-reactive protein (CRP), an inflammatory marker that statistically predicts future cardiovascular risk, has been reported to be associated with plasma lipid level changes. Whether CRP genetic variants affect lipid metabolism is of importance to investigate. A community-based study population including 2,731 adult subjects aged 18–62 years was used to evaluate the association of CRP gene with dyslipidemia and five tagging SNPs (tagSNPs) were genotyped. Multiple logistic regression was applied to further evaluate relationships between the SNPs and lipid metabolism abnormality and general linear model was applied to compare plasma lipid levels between genotypes. Association analyses indicated that recessive model of SNPs rs876537 and rs4285692 had significant association with elevated HDL after adjustment for covariates. Odds ratio (OR) of rs876537 were 0.60 for HDL > 1.54 versus 1.04–1.54 mmol/L (P = 0.011), as well as, ORs were 0.617 for HDL > 1.83 versus ≤1.35 mmol/L (P = 0.002) and 0.724 for HDL = 1.59–1.83 versus ≤1.35 mmol/L (P = 0.028) respectively. OR of rs4285692 was 0.634 for HDL > 1.83 versus ≤1.35 mmol/L (P = 0.027). Further stratification analysis found significant associations of rs10737175 with elevated HDL (>1.54 vs. 1.04–1.54 mmol/L, OR 0.629 and P = 0.027) and elevated TG (≥1.70 vs. <1.70 mmol/L, ORs of additive and dominant models were 0.628, 0.545 and P values were 0.006, 0.003 respectively) in female. rs4285692 was significantly associated with elevated LDL (≥3.37 vs. <3.37 mmol/L), ORs equaled to 1.532, 2.281 for additive model and recessive model and P values were 0.028, 0.024 respectively in male. Furthermore, quantitative trait analysis indicated the variation T to C of rs876537 significantly affect decreased plasma HDL level (P = 0.014). Our findings suggest that CRP genetic polymorphisms independently had positive association with the risk of HDL, LDL and TG elevating and further replication in other large population and biological function research would be warranted.  相似文献   

5.
Osteoprotegerin (OPG) is a secretory glycoprotein that belongs to the tumor necrosis factor receptor family and plays a role in atherosclerosis. The present study aimed to evaluate whether OPG gene (TNFRSF11B) polymorphisms are involved in ischemic stroke in an Italian population with diabetes. Participants in a retrospective case–control study included 364 diabetic patients (180 males, 184 females) with history of ischemic stroke and 492 diabetic subjects without history of ischemic stroke (252 males, 240 females). The T245G, T950C, and G1181C polymorphisms of the OPG gene were analyzed by polymerase chain reaction and restriction fragment length polymorphism. We found that the T245G, T950C, and G1181C gene polymorphisms of the OPG gene were significantly (34.1 vs. 9.5 %, P < 0.0001; 30.8 vs. 6.3 %, P < 0.0001 and 26.4 vs. 11.6 % P < 0.0001, respectively) and independently (adjusted OR 5.15 [3.46–7.68], OR 6.63 [4.26–10.31], and OR 3.03 [2.04–4.50], respectively) associated with history of ischemic stroke. We also found that these three polymorphisms act synergistically in patients with stroke history. The TNFRSF11B gene polymorphisms studied are associated with history of ischemic stroke and synergistic effects between these genotypes might be potential markers for cerebrovascular disorders.  相似文献   

6.
To investigate whether the NAD(P)H:quinone oxidoreductase 1 (NQO1) gene polymorphisms determine the Platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC) in a Chinese cohort. A total of 391 patients with inoperable advanced stage of NSCLC, namely, stage III (A + B) and IV NSCLC, and 663 age-and sex-matched healthy were enrolled. The effects of chemotherapy were evaluated. NQO1 C609T polymorphism was determined. The NSCLC patients had a significantly higher prevalence of TT than control subjects (33.76 vs. 21.67 %, P < 0.001). For allele comparison, NSCLC subjects had lower T allele frequency than controls as well (55.63 vs. 44.42 %, P < 0.001). multivariate regression analyses showed the TT carriage had a significantly increased risk for development of NSCLC after adjustments with age, sex, smoke, and cancer family history (OR 1.681, 95 % CI 1.242–2.274, P = 0.001). The TT genotype distribution was significantly higher in non-responders than in responders (31.85 vs. 21.96 %, P = 0.003). Logistic regression analysis showed TT genotype carriers had less chance to gain chemotherapy response compared to CC genotype carriers (OR 0.399, P = 0.003) after adjustment with sex, age, tumor histology, disease stage, and chemotherapy regimens. The NQO1 C609T polymorphism is an important molecular marker for advanced NSCLC, since it is associated with the NSCLC risk as well as the response status of platinum-based chemotherapy.  相似文献   

7.
Despite the increasing incidence of combined small-cell lung cancer (C-SCLC) in recent years, there have not been many data on clinical prognostic factors predicting prognosis of C-SCLC patients. In present study, we sought pretreatment features especially basic laboratory parameters predicting survival of C-SCLC. We analyzed 613 small-cell lung cancer (SCLC) patients at our institution between January 2005 and December 2010. We identified 114 patients with C-SCLC. The pathologic and clinical characteristics of these patients were reviewed. Data of laboratory parameters obtained during regular examinations at diagnosis of these patients were examined. The Kaplan–Meier method was used to calculate the survival rate and depict the survival curves. The Cox regression model was used to analyze the independent factors affecting the overall survival (OS). These data were compared with the results obtained from our 499 pure SCLC patients who presented during the same time period. Of the 613 SCLC patients analyzed, 18.6 % of the patients presented with C-SCLC. No difference in OS was observed in patients with C-SCLC and patients with pure SCLC (P = 0.995). The Kaplan–Meier survival curves revealed that poor ECOG-PS (P < 0.001), extensive disease (P < 0.001), pathologic subtype of SC/LC (P < 0.001), not receiving surgery (P = 0.001), elevated serum lactate dehydrogenase (LDH) (P = 0.005), elevated NSE (P = 0.043), and elevated neutrophile–lymphocyte ratio (NLR) (P = 0.018) were associated with adverse prognosis of patients with C-SCLC. By multivariate analysis, OS was affected by ECOG-PS (hazard ratio 2.001, P = 0.012), disease extent (hazard ratio 3.406, P < 0.001), and NLR (hazard ratio 1.704, P = 0.030) in C-SCLC patients, while the risk factors that influenced the prognosis of the patients with pure SCLC were ECOG-PS (hazard ratio 2.132, P < 0.001), disease extent (hazard ratio 1.482, P < 0.001), and LDH (hazard ratio 1.811, P < 0.001). Patients with C-SCLC carry a similar prognosis than those with pure small-cell variety. Easily accessible pretreatment parameters such as NLR should be considered in defining the prognosis of C-SCLC patients besides disease extent and performance status.  相似文献   

8.
In-stent restenosis (ISR) remains the most common complication of percutaneous coronary intervention. Due to shared risk factors, it is postulated that non-alcoholic fatty liver disease (NAFLD) patients have an increased risk of ISR. This study aimed to determine the association between NAFLD and ISR in patients after bare metal stenting. This study included a cohort of 210 consecutive patients (150 men and 60 women) undergoing follow-up angiography. The primary end-point was angiographic ISR. Multivariate logistic regression analysis was used to identify independent risk factors for ISR. The cumulative ISR rate during follow-up was analyzed by Kaplan–Meier method. Subgroup analyses were also done for different gender. The ISR rate was 29.5 %. Patients with NAFLD had a significantly higher prevalence of ISR than patients without NAFLD (43.3 vs. 16.0 %, P < 0.001). In logistic regression analysis, NAFLD was associated with increased ISR, independent of low-density lipoprotein cholesterol, body mass index (adjusted odds ratio: 2.688, 95 % confidence intervals: 1.285–5.537, P < 0.001). Male NAFLD patients had a higher prevalence of ISR than patients without NAFLD (48.4 vs. 15.3 %, P < 0.001), while the prevalence of ISR in female patients with and without NAFLD were comparable (7.7 vs. 17.0 %, P = 0.404). Kaplan–Meier analysis showed a significant association between NAFLD and ISR in all patients (log-rank P = 0.008) and in male subgroup (log-rank P = 0.033), but not in female subgroup (log-rank P = 0.313). This preliminary study suggests that NAFLD could independently associate with a high prevalence of ISR, especially in male patients.  相似文献   

9.
Psoriasis (PS) is a common hyperproliferative and chronic inflammatory disease of the skin. It is influenced by both genetic and environmental factors. The ADAM33 (a disintegrin and metalloproteinase 33) gene located on chromosome 20p13, has recently been identified as an asthma-susceptibility gene by positional cloning. Recently, ADAM33 has been suspected to be associated with PS. To study the association between ADAM33 and PS in the northeastern Chinese population. A total of 240 PS patients and a control group of 237 healthy volunteers were recruited for this study. Five polymorphic loci (V4, T+1, T2, T1, S2) of ADAM33 were selected for genotyping. Genotypes were determined by using the polymerase chain reaction–restriction fragment length polymorphism method. We observed the frequency of the rs2787094 C allele was significantly higher in cases than in controls (50 vs. 33 %, P < 0.0001).Similarly, the rs528557 C allele exhibited a significantly increased frequency in PS patients compared with healthy controls (35 vs. 21 %, P < 0.0001). We also found that the frequencies of H3 (CGGAC), H6 (CGGGG) haplotypes were significantly higher in the case group than in the control group (P = 0.006, 0.028, respectively). In contrast, the haplotype H9 (GAAAG) was more common in the control group than in the case group (P = 0.018). Our data suggest that the ADAM33 polymorphisms may be associated with PS in the northeastern Chinese population.  相似文献   

10.
α-Lipoic acid (αLA), as an inductor of hydrogen peroxide (H2O2) and nitrogen oxide (NO) generation and modulator of thiol redox status, plays an important role in cell signalling pathways. The study was designed to observe the effect of αLA on inflammatory response through changes in H2O2 and NO levels as well as thiol redox status. Sixteen physically active males were randomly assigned to one of two groups: placebo or αLA (1,200 mg?d?1 for 10 days prior to exercise). The exercise trial involved a 90-min run at 65 % VO2max (0 % gradient) followed by 15-min eccentric phase at 65 % VO2max (?10 % gradient). Blood samples were collected before the exercise trial and then again 20 min, 24, and 48 h after. αLA significantly elevated H2O2 but reduced NO generation before or after exercise. Thiol redox status (GSHtotal-2GSSG/GSSG) increased by >50 % after αLA and exercise (ANOVA, P?<?0.05) and correlated with changes in cytokines interleukin-6 (IL-6) (r?=??0.478, P?<?0.05) and IL-10 (r?=??0.455, P?<?0.05). This was caused by strong effect of αLA on GSSG concentration. αLA elevated IL-6 and IL-10 levels at 20 min after exercise and decreased in interleukin-1β and tumor necrosis factor α before and after exercise. This enhanced the regeneration of injured muscles. Creatine kinase activity tended to lower values after αLA intake. The study suggests that the combination of intense exercise with α-lipoic acid intake might be useful to improve the skeletal muscle regeneration through changes in inflammatory response which are associated with H2O2 and NO generation as well as thiol redox status.  相似文献   

11.
The aim of this study was to assess the depression status and associated factors in occupational truck drivers. Four hundred and forty-one male occupational truck drivers were recruited from transport companies. The self-rating depression scale (SDS) and Eysenck Personality Questionnaire-R Short Scale were used to measure the depression status and factors associated with it for occupational truck drivers. The observed SDS of (mean ± SD) 52.91 ± 11.41 was significantly higher than the average national score (41.99 ± 10.57). There were 237 cases of depression, making the incidence of 53.74 %: 116 (26.30 %) patients had mild depression, 104 (23.58 %) moderate depression, and 17 (3.85 %) severe depression. Drivers with <1 year of experience had the highest SDS score; their score was significantly (p < 0.05) different from the one in more experienced drivers. Furthermore, the SDS score in drivers with high school education was significantly higher than in drivers with secondary education (53.41 ± 11.67 vs. 50.62 ± 11.77, respectively; p < 0.05). SDS scores positively correlated with extroversion and neuroticism, and negatively correlated with psychoticism. In conclusion, depression is present in professional drivers, especially those with <1 year of driving experience. The level of depression is associated with driving experience, education status and personality. Based on this study, we propose to establish psychological health profiles for each professional driver, and to provide psychological counseling to them, especially drivers with <1 year of experience.  相似文献   

12.
The patatin like phospholipase domain-containing (PNPLA3) I148M variant is the strongest genetic factor associated with elevated alanine transaminase (ALT) levels in different populations, particularly in Hispanics who have the highest 148M risk allele frequency reported to date. It has been suggested that Indigenous ancestry is associated with higher ALT levels in Mexicans. The aim of the present study was to assess the frequency of the PNPLA3 148M risk allele in Mexican indigenous and Mestizo individuals, and to examine its association with serum ALT levels. The study included a total of 1624 Mexican individuals: 919 Indigenous subjects from five different native groups and 705 Mexican Mestizo individuals (141 cases with ALT levels ≥40 U/L and 564 controls with ALT <40 U/L). The I148M polymorphism was genotyped by TaqMan assays. The frequency of elevated ALT levels in Indigenous populations was 18.7 %, and varied according to obesity status: 14.4 % in normal weight, 19.9 % in overweight and 24.5 % in obese individuals. The Mexican indigenous populations showed the highest reported frequency of the PNPLA3 148M risk allele (mean 0.73). The M148M genotype was significantly associated with elevated ALT levels in indigenous individuals (OR = 3.15, 95 % CI 1.91–5.20; P = 7.1 × 10?6) and this association was confirmed in Mexican Mestizos (OR = 2.24, 95 % CI 1.50–3.33; P = 8.1 × 10?5). This is the first study reporting the association between M148M genotype and elevated ALT levels in Indigenous Mexican populations. The 148M allele risk may be considered an important risk factor for liver damage in Mexican indigenous and Mestizo populations.  相似文献   

13.
Bone marrow stromal cells (BMSCs) have been extensively used for tissue engineering. However, the effect of Ca2+ on the viability and osteogenic differentiation of BMSCs has yet to be evaluated. To determine the dose-dependent effect of Ca2+ on viability and osteogenesis of BMSCs in vitro, BMSCs were cultured in calcium-free DMEM medium supplemented with various concentrations of Ca2+ (0, 1, 2, 3, 4, and 5 mM) from calcium citrate. Cell viability was analyzed by MTT assay and osteogenic differentiation was evaluated by alkaline phosphatase (ALP) assay, Von Kossa staining, and real-time PCR. Ca2+ stimulated BMSCs viability in a dose-dependent manner. At slightly higher concentrations (4 and 5 mM) in the culture, Ca2+ significantly inhibited the activity of ALP on days 7 and 14 (P < 0.01 or P < 0.05), significantly suppressed collagen synthesis (P < 0.01 or P < 0.05), and significantly elevated calcium deposition (P < 0.01) and mRNA levels of osteocalcin (P < 0.01 or P < 0.05) and osteopontin (P < 0.01 or P < 0.05). Therefore, elevated concentrations of extracellular calcium may promote cell viability and late-stage osteogenic differentiation, but may suppress early-stage osteogenic differentiation in BMSCs.  相似文献   

14.
Telomeres are highly conserved nucleoprotein structures which protect genome integrity. The length of telomeres is influenced by both genetic and environmental factors, but relatively little is known about how different hereditary and environmental factors interact in determining telomere length. We manipulated growth rates and timing of maturation by exposing full-sib nine-spined sticklebacks (Pungitius pungitius) to two different temperature treatments and quantified the effects of temperature treatments, sex, timing of maturation, growth rate and family (genetic influences) on telomere length. We did not find the overall effect of temperature treatment on the relative telomere length. However, we found that variation in telomere length was related to timing of maturation in a sex- and temperature-dependent manner. Telomere length was negatively related to age at maturation in elevated temperature and early maturing males and females differed in telomere length. Variation in growth rate did not explain any variation in telomere length. The broad sense heritability (h 2) of telomere length was estimated at h 2 = 0.31 ? 0.47, suggesting predominance of environmental over genetic determinants of telomere length variability. This study provides the first evidence that age at maturation together with factors associated with it are influencing telomere length in an ectotherm. Future studies are encouraged to identify the extent to which these results can be replicated in other ectotherms.  相似文献   

15.
Overall nutritional status has been proved associated with people’s health. The overall nutritional status of children in Kashin-Beck disease (KBD) areas has been overlooked for decades. Therefore, it is worth investigating in the current generation to gather evidence and make suggestions for improvement. A cross-sectional study with three 24-h dietary recalls was conducted to collect raw data on the daily food intake of children. Recorded food was converted into daily nutrient intakes using CDGSS 3.0 software. WHO AnthroPlus software was used to analyse the BMI-for-age z-score (BAZ) for estimating the overall nutrition status of children. All the comparisons and regression analyses were conducted with SPSS 18.0 software. Multiple nutrient intakes among children from the Se-supplemented KBD-endemic were under the estimated average requirement. The protein-to-carbohydrate ratio (P/C ratio) was significantly higher in children from the non-Se-supplemented KBD-endemic area than the other areas (P < 0.001). The children’s BAZ was negatively associated with age (B = ?0.095, P < 0.001) and the number of KBD relatives (B = ?0.277, P = 0.04), and it was positively associated with better housing conditions, receiving colostrum, and daily intakes of niacin and zinc by multivariate regression analysis (F = 10.337, R = 0.609, P < 0.001).Compared to non-Se-supplemented KBD-endemic area and non-endemic areas, children in Se-supplemented KBD-endemic areas have an insufficient intake of multiple nutrients. School breakfast and lunch programmes are recommended, and strict implementation is the key to ensuring a positive effect.  相似文献   

16.
There is no study that assessed the effect of co-supplementation of iron and vitamin C on biomarkers of oxidative stress in non-anemic iron-deficient females. We investigated the effects of iron vs. iron?+?vitamin C co-supplementation on biomarkers of oxidative stress in iron-deficient girls. In a double-blind randomized controlled clinical trial, performed among 60 non-anemic iron-deficient girls, participants were randomly assigned to receive either 50 mg/day elemental iron supplements or 50 mg/day elemental iron?+?500 mg/day ascorbic acid for 12 weeks. Fasting blood samples were taken at baseline, weeks 6 and 12 for assessment of biomarkers of oxidative stress. Compared with the baseline levels, both iron and iron?+?vitamin C supplementation resulted in a significant reduction in serum malondialdehyde (MDA) levels (P time?<?0.001) and remarkable elevation in serum total antioxidant capacity (TAC; P time?<?0.001) and vitamin C levels (P time?=?0.001); however, comparing the two groups we failed to find an additional effect of iron?+?vitamin C supplementation to that of iron alone on serum TAC and MDA levels (P group was not statistically significant). Iron?+?vitamin C supplementation influenced serum vitamin C levels much more than that by iron alone (P group?<?0.01). We also found a significant interaction term between time and group about serum vitamin C levels while this interaction was not significant about serum TAC and MDA levels. In conclusion, we found that iron supplementation with/without vitamin C improve biomarkers of oxidative stress among non-anemic iron-deficient females and may strengthen the antioxidant defense system by decreasing reactive oxygen species. Co-supplementation of iron?+?vitamin C has no further effect on oxidative stress compared with iron alone.  相似文献   

17.
Phosphorus (P) availability in terrestrial ecosystems depends on soil age, climate, parent material, topographic position, and biota, but the relative importance of these drivers has not been assessed. To ask which factor has the strongest influence on long- and short-timescale metrics of P availability, we sampled soils across a full-factorial combination of two parent materials [quartz diorite (QD) and volcaniclastic (VC)], three topographic positions (ridge, slope, and valley), and across 550 m in elevation in 17 sub-watersheds of the Luquillo Mountains, Puerto Rico. VC rocks had double the P content of QD (600 vs. 300 ppm; P < 0.0001), and soil P was similarly approximately 2× higher in VC-derived soils (P < 0.0001). Parent material also explained the most variance in our two other long-timescale metrics of P status: the fraction of recalcitrant P (56% variance explained) and the loss of P relative to parent material (35% variance explained), both of which were higher on VC-derived soils (P < 0.0001 for both). Topographic position explained an additional 10–15% of the variance in these metrics. In contrast, there was no parent material effect on the more labile NaHCO3- and NaOH-extractable P soil pools, which were approximately 2.5× greater in valleys than on ridges (P < 0.0001). Taken together, these data suggest that the relative importance of different state factors varies depending on the ecosystem property of interest and that parent material and topography can play sub-equal roles in driving differences in ecosystem P status across landscapes.  相似文献   

18.
Cross-sectional studies have associated short telomere length with smoking, body weight, physical activity, and possibly alcohol intake; however, whether these associations are due to confounding is unknown. We tested these hypotheses in 4,576 individuals from the general population cross-sectionally, and with repeat measurement of relative telomere length 10 years apart. We also tested whether change in telomere length is associated with mortality and morbidity in the general population. Relative telomere length was measured with quantitative polymerase chain reaction. Cross-sectionally at the first examination, short telomere length was associated with increased age (P for trend across quartiles = 3×10−77), current smoking (P = 8×10−3), increased body mass index (P = 7×10−14), physical inactivity (P = 4×10−17), but not with increased alcohol intake (P = 0.10). At the second examination 10 years later, 56% of participants had lost and 44% gained telomere length with a mean loss of 193 basepairs. Change in leukocyte telomere length during 10 years was associated inversely with baseline telomere length (P<1×10−300) and age at baseline (P = 1×10−27), but not with baseline or 10-year inter-observational tobacco consumption, body weight, physical activity, or alcohol intake. Prospectively during a further 10 years follow-up after the second examination, quartiles of telomere length change did not associate with risk of all-cause mortality, cancer, chronic obstructive pulmonary disease, diabetes mellitus, ischemic cerebrovascular disease, or ischemic heart disease. In conclusion, smoking, increased body weight, and physical inactivity were associated with short telomere length cross-sectionally, but not with telomere length change during 10 years observation, and alcohol intake was associated with neither. Also, change in telomere length did not associate prospectively with mortality or morbidity in the general population.  相似文献   

19.
Multiple determinant factors are involved in the occurrence and progression of esophageal squamous cell carcinoma (ESCC). Human papillomavirus (HPV) and human leukocyte antigen (HLA) polymorphism were identified as important factors. This study examined the associations between the development of Kazakh ESCC and the determinant factors including HLA-DRB1*0901, 1501; DQB1*0301, 0602; high-risk HPV infection in the area of Xinjiang, China. 200 Kazakh patients with ESCC and 150 controls were recruited, and polymerase chain reaction (PCR) was performed to detect HLA-DRB1*0901, 1501 and DQB1*0301,0602 using sequence-specific primers (SSPs). HPV16 was detected in esophageal specimens using PCR. HPV16 infection rate in Kazakh ESCC case group was 41 %, significantly higher than that of control group 14 % (OR = 3.62; 95 % CI, 2.15–6.09; P < 0.001). A positive association between ESCC and HLA-DRB1*1501 (OR = 2.46, P < 0.0125) or HLA-DQB1*0301 (OR = 3.34, P < 0.0125) alleles was observed. Similar tendencies were observed for HLA-DRB1*1501 (OR = 3.095, P < 0.0125) and HLA-DQB1*0301 (OR = 2.410, P < 0.0125) alleles with HPV16-positive ESCC. HLA-DRB1*1501, HLA-DQB1*0301 and DQB1*0602 were significantly associated with ESCC when the age was ≥55 years (P < 0.0125 for all), whereas only HLA-DQB1*0301 was significantly associated with ESCC when the age was <55 years (P < 0.0125). HLA-DRB1*1501 and HLA-DQB1*0301 were significantly associated with an increase in ESCC occurrence in females (P < 0.0125), whereas only HLA-DQB1*0301 was significantly associated with ESCC in males. Moreover, the occurrence of HLA-DQB1*0602 gene in poorly differentiated ESCC group (68.8 %) was slightly higher than that of well-differentiated squamous cell carcinoma group (31.2 %). The difference was not statistically significant (P > 0.0125). The study suggests that HLA-DRB1*1501 and HLA-DQB1*0301 may influence the immune response to specific tumor and HPV-encoded epitopes and affect the risk of Kazakh ESCC in XinJiang, China.  相似文献   

20.
Use of non-viable somatic cells for hand-made cloning (HMC) can enable production of cloned animals from tissues obtained from elite or endangered dead animals. Buffalo skin fibroblast cells were rendered non-viable by heat treatment and used for HMC. Although fusion (93.6 ± 1.72 vs 67.1 ± 2.83%) and cleavage (90.3 ± 1.79 vs 65.8 ± 1.56%) rate was lower (P < 0.001) than that for controls, blastocysts could be successfully produced. However, blastocyst rate (34.1 ± 2.43 vs 6.9 ± 2.18%, P < 0.001) and total cell number of blastocysts (TCN, 221.3 ± 25.14 vs 151.1 ± 21.69, P < 0.05) were lower and apoptotic index (4.8 ± 1.06 vs 10.9 ± 1.21) was higher (P < 0.001) than that of controls. In another experiment, ear tissue of slaughterhouse buffaloes was preserved in mustard oil at room temperature for 48 h following which somatic cells were harvested by enzymatic digestion and used for HMC. Although fusion (96.8 ± 1.48 vs 84.2 ± 3.19%), cleavage (89.6 ± 3.59 vs 77.2 ± 3.99%), and blastocyst rate (36.9 ± 7.45 vs 13.1 ± 6.87%) were lower (P < 0.01), TCN (223.0 ± 27.89 vs 213.3 ± 28.21) and apoptotic index (3.97 ± 0.67 vs 5.22 ± 0.51) of blastocysts were similar to those of controls. In conclusion, HMC can be successfully used for production of blastocysts from non-viable cells and from cells obtained from freshly slaughtered buffaloes. This can pave the way for the restoration of farm or wild animals by HMC if somatic cells could be obtained within a few hours after their death.  相似文献   

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