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1.
Microparticles (MPs) are vesicles released from activated or apoptotic cells. MP derive from various cells, most notably platelets, but also leucocytes, lymphocytes, erythrocytes, and endothelial cells. The aim of this study was to investigate endothelial MP (EMP), platelet MP (PMP), lymphocyte MP and monocyte MP and TF-positive MPs (TF+ MPs) in patients with coronary heart disease (CHD), and to evaluate the correlation of these MPs with Interleukin-6 (IL-6) and C-reactive protein (CRP). Different cell-derived MPs and TF+ MPs were analyzed by flow cytometry in 40 patients with myocardial infarction (MI), 30 unstable angina (UA), 20 stable angina (SA) and 20 healthy individuals, and IL-6 and CRP were determined by ELISA and special protein analyzer, respectively. Compared with SA and control, EMP and PMP was significantly elevated in MI and UA (P < 0.001), and TF+ MPs was significantly elevated in MI and UA (P < 0.001). EMP and PMP correlated with IL-6 (r = 0.822, P < 0.001 and r = 0.567, P < 0.001; respectively) or CRP level (r = 0.597, P < 0.001 and r = 0.66, P < 0.001; respectively). Different cell-derived MPs in CHD may indicate the different pathophysiological changes in vessels, and MPs may both participate in the development of thrombosis and enhance the vascular inflammation.  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.
Barbronia weberi were collected from Hydrilla verticillata purchased from aquarium suppliers in Melbourne, Australia and additional B. weberi were obtained from aquatic plants in Canberra, ACT, Australia. Adult leeches fed Tubifex sp. ad libitum successfully reproduced under laboratory conditions (21 ± 5?°C ). Reproductively mature B. weberi produced cocoons every week for up to three months at which time the adults began to senesce. Cocoons contained one to five (barx=2.41±0.78 SD, N=58) eggs with juveniles leaving the cocoon within 27 ± 3.4 SD days (N=13) of cocoon production. Juvenile B. weberi reached reproductive maturity within four months (N=7) of hatching and had a maximum growth rate of 1.10 mm2 d?1 once they left the cocoon at around 30 days. Individual egg volume (r=0.63, scaling exponent = 1.21) and cocoon volume (r=0.65, scaling exponent = 1.24) showed a significant (P<0.001) and nearly isometric relationship when scaled with maternal body size. Because this species can grow rapidly and produce a large number of eggs over a short period of time and can piggyback with plant species and travel through the aquarium trade, there is potential for B. weberi to rapidly invade new localities.  相似文献   

4.
To understand the influence of temperature on host–parasitoid interactions as a consequence of climatic change, we studied development, survival, and fecundity of field and laboratory strains of the Helicoverpa armigera larval endoparasitoid, Campoletis chlorideae at five different temperatures under laboratory conditions. Post-embryonic development period and degree-days required for completing the life cycle by both the strains decreased by 2.5 and 1.5 folds at 27°C compared to 18°C. Post embryonic development period showed a negative (r = −0.99, P < 0.001) and the development rate a positive (r = 0.99, P < 0.001) association with an increase in temperature. However, no parasitoid larvae survived in H. armigera larvae reared at 12 and 35°C after parasitization, suggesting that temperatures ≥35°C as a result of global warming will be lethal for development and survival of immature stages of C. chlorideae. Adult longevity was negatively associated (r = −0.91 to −0.96, P < 0.001) with temperatures between 12 and 35°C. The parasitoid adults stored at 12°C survived for longer period and exhibited higher fecundity than those kept at 27°C, but the efficiency of parasitism and adult emergence were quite low. Sex ratio of the progeny at 12°C was highly male-biased than the insects kept at 27°C. Laboratory strain of the parasitoid exhibited better survival, and the adults lived longer than the field strain at 18°C than at 27°C. Therefore, C. chlorideae adults stored at 18°C could be used for parasitism, while the immature stages should be reared at 27°C for mass production of the parasitoid for biological control of H. armigera.  相似文献   

5.
Estrogen receptor alpha (ERα), that mediates the biologic effects of estrogen in estrogen-sensitive tissues like breast, is genetically polymorphic. To evaluate the association between ?397 PvuII (T>C) and ?351 XbaI (A>G) restriction fragment length polymorphisms (RFLPs) in intron 1 of ERα gene and susceptibility of breast cancer, we undertook a case–control study in BRCA1 185delAG and 5382insC/BRCA2 6174delT negative Portuguese women. The study population consisted of 107 patients with histological diagnosis of breast cancer and 121 women with no history of breast cancer. Genomic DNA was extracted from blood samples and genotyping analyses were performed by PCR–RFLP. XbaI polymorphism was associated with a significant reduced risk of breast cancer for carriers of the x allele in homozygozity (OR 0.178; 95 % CI 0.070–0.456; P < 0.001) or heterozigozity (OR 0.223; 95 % CI 0.089–0.561; P = 0.001). The PvuII polymorphism was associated with a non-significantly reduced risk. The combined analysis of PvuII and XbaI polymorphisms revealed none synergistic effect of the two genotypes, except for simultaneous carriers of pp and xx genotypes, that have a reduced risk of breast cancer (OR 0.226; 95 % CI 0.049–1.035; P = 0.044). The combination of PvuII and XbaI genotypes into haplotypes showed that carriers of two copies of the px (ppxx) haplotype had a reduced risk of breast cancer (OR 0.405; 95 % CI 0.194–0.843; P = 0.014), compared with PX (PPXX + PPXx + PpXX + PpXx) haplotypes. PvuII and XbaI polymorphisms were in linkage disequilibrium both in cases (D = 0.044, r2 = 0.049, X2 = 5.216, P = 0.022) and controls (D = 0.090, r2 = 0.139, X2 = 16.819, P < 0.001), but not in the entire sample population analyzed as a whole (D = 0.087, r2 = 0.0076, X2 = 1.733, P = 0.188). In conclusion, in this case–control study we found that ERα gene XbaI polymorphism may modify individual susceptibility for breast cancer in this population.  相似文献   

6.
Experimental studies evaluating the simultaneous effects of consumers, nutrients, and other biotic/abiotic factors on intact, natural food webs are rare, particularly among ecosystems of varying trophic conditions. We conducted a series of in situ studies that used nutrient-diffusing substrata with nitrogen (N) and phosphorus (P) concentrations in a full factorial design in three temperate, limestone streams in Pennsylvania across a trophic gradient (mesotrophic, eutrophic, and hypereutrophic streams). We assessed differences in algal and macroinvertebrate biomass, taxonomic composition, and functional groups relative to amended nutrients across the trophic gradient; as such, these results facilitated predictions about regulators of food web structure. All factors varied significantly among the streams (e.g., algal biomass P = 0.005, macroinvertebrate biomass P < 0.001, algal diversity P = 0.006, macroinvertebrate diversity P < 0.001, algal group P < 0.001, macroinvertebrate guilds P < 0.001); the streams, however, did not exhibit simple responses to nutrient amendment. Algal and macroinvertebrate biomass and diversity responded greatest in the mesotrophic stream while grazing seemed to be a strong factor preventing algal nutrient response in the eutrophic and hypereutrophic streams. Brillouin’s Evenness Index was most influenced by nutrient amendment (nutrient effect on algae and macroinvertebrates P = 0.021). As such, we concluded that biomass and diversity were mediated by complexity within intermediate trophic levels.  相似文献   

7.
The artificial fertilization of the puffer,Takifugu chrysops (Hilgendorf), was carried out at Sajima in Yokosuka City on May 22, 1984. Hatched larvae were reared for a period of about 150 days. The spawning period seems to extend from mid to late May in the eastern part of Sagami Bay. The eggs were spherical, pale milky white and semitransparent, demersal and adhesive in nature, measuring 1.32±0.04 mm in diamter, and with a cluster of small oil-globules. The incubation period was about 162 hours at a water temperature of 17.4 to 21.8°C. During embryonic development, the only pigment cells that appeared on the embryo were the black chromatophores. The newly hatched larvae measured from 2.72 to 3.06 mm TL, averaging 2.87±0.1 mm TL, and 22–23 (9 + 13?14) myomeres. At yolk absorption, 4 days after hatching, the larvae attained 3.64–3.79 mm TL. On the 11th day, postlarvae averaged 4.69±0.24 mm TL. Larval finfolds disappeared and rudimental dorsal, anal and caudal fins were formed. There were two large clusters of melanophores, one on the back, exteding from the mid-base of the dorsal fin to the caudal peduncle region, the other along the anal fin base. The color of the body began to turn pale green to brownish-orange and spinelike scales appeared on the belly. Eighteen days after hatching (7.02±0.27 mm TL), the caudal notochord began to turn up and a “constriction” appeared on the posterior margin of the caudal fin membrane. This notch moved upwards as the notochord upturning advances. The larvae attained full fin ray counts and reached the juvenile stage at 9.1-9.5 mm TL, 24 days after hatching. Characteristic black blotches on the back and specific brownish orange body color appeared at the stage of 20 mm TL, 24 days after hatching. The growth during the larval stage and early juvenile stage (24 to 51 days after hatching) were expressed by the following equations, wherey is total length (mm) andx is days after hatching.y 1=2.8424× 1.05099 (0≦x≦24)y 2 = 3.7872×1.0372x (24≦x≦51)  相似文献   

8.
The long intergenic non-coding RNA LINC00312, also called NAG7, was first cloned by our group. Our previous studies have found that LINC00312 could inhibit proliferation and induce apoptosis in nasopharyngeal carcinoma (NPC) cells but also stimulate NPC cell invasion. However, the relevance of LINC00312 in NPC progression or in patient outcomes has not been reported. This study aims to assess the possible correlations of LINC00312 expression with NPC progression and its potential prognostic predictive ability in NPC outcomes. A NPC tissue microarray, which included 561 normal and NPC tissue cores, was used to detect LINC00312 expression, and we found that LINC00312 was significantly down-regulated in NPC tissues compared with non-cancerous nasopharyngeal epithelium tissues. Positive expression of LINC00312 was negatively correlated with tumor size (P < 0.001) but positively correlated with lymph node metastasis (P = 0.002). A receiver operating characteristic (ROC) analysis revealed that LINC00312 expression could distinguish non-cancerous patients from NPC patients (P < 0.001, sensitivity: 72.1 %, specificity: 87.7 %). We also found that LINC00312 was strongly negatively correlated with EBER-1, a non-coding RNA transcribed by Epstein-Barr Virus, in NPC (r = ?0.384, P < 0.001). In the final logistic regression analysis model, the abnormal expression of LINC00312 and EBER-1 were found to be independent contributors to nasopharyngeal carcinogenesis (P < 0.001, P < 0.001, respectively). A survival analysis revealed that LINC00312 could predict a good prognosis of no lymph node metastasis (Disease Free Survival (DFS): P = 0.005, Overall Survival (OS): P = 0.001) and a poor prognosis of lymph node metastasis (DFS: P = 0.011, OS: P = 0.001) in NPC patients. Low expression of LINC00312 was an independent risk factor for OS in multivariate analyses (P = 0.017). These observations indicated that LINC00312 could represent a potential biomarker for metastasis, progression and prognosis in NPC.  相似文献   

9.
Soybean (Glycine max) agriculture is characterized by a high proportion of mono-cropping which results in reduced crop production in the Northeast China. Among all biotic and abiotic factors, changes in soil microbial communities induced by root activities, especially root exudates, might play an important role in these effects. The aim of the present study was to investigate response of microbial biomass and two major beneficial microbial functional groups, ammonia-oxidizing bacteria (AOB), and arbuscular mycorrhizal fungi (AMF), to root exudates in an experimental field under continuous soybean monoculture for 13 years. The results showed that microbial biomass carbon changed significantly with years of mono-cropping and correlated with concentrations of genistein (r = 0.4399, P < 0.001) and daidzein (r = 0.4082, P < 0.05) in the rhizosphere. However, root exudates had little effect on the nitrifier community, but reduced nitrification in the rhizosphere. In contrast, total AMF hyphal length was significantly stimulated by genistein (r = 0.5252, P < 0.01). There was a trend that AMF spore density increased in the rhizosphere with increasing years of mono-cropping, while AMF infection was constant over time, which might be attributed to competition between AMF and soil-borne fungal pathogens, as the results of stimulatory effect of flavonoids on fungal community, especially fungal pathogens. Our results suggested that the yield reduction in the beginning of continuous soybean monoculture could be partially attributed to nitrogen availability and yield stabilization after few years to stimulatory effects on AMF. These results imply that some of plant root exudates play a crucial role in changing the soil microbial community, and that underground ecosystem functioning is also affected by interactions among microbial functional groups.  相似文献   

10.
In the Seno de Reloncaví, southern Chile, seasonal changes in dry weight (DW) and elemental composition (CHN) were studied in embryo (initial embryonic stage), newly hatched zoeae, and newly settled megalopae of a porcelain crab, Petrolisthes laevigatus. Samples were taken throughout the seasons of egg laying (March-December), hatching (August-February), and settlement (October–February). Values of DW and CHN per embryo or larva, respectively, were consistently minimum in the middle of each season and maximum near its beginning and end. Patterns of seasonal variation in early embryonic biomass may thus be carried over to larvae at hatching and, possibly, to the settlement stage. Such carry-over effects may be selectively advantageous, as zoeae released at the beginning or near the end of the hatching season face conditions of poor planktonic food availability in combination with low winter temperatures or decreasing temperatures at the end of summer (enforcing long development duration). Hence, an enhanced female energy allocation into egg production may subsequently translate to enhanced yolk reserves remaining at hatching, allowing for a larval development under unfavourable winter conditions. In summer, by contrast, plankton productivity and temperatures are generally high, allowing for fast larval growth and development. This coincides with minimal biomass and energy contents both at hatching and settlement. In conclusion, our data suggest that seasonal patterns in the biomass of early developmental stages of P. laevigatus may reflect phenotypic variability as an adaptive response to predictable variations in environmental conditions, allowing this species to reproduce in temperate regions with marked seasonality in water temperature and plankton productivity.  相似文献   

11.
In the current study, we measured urinary angiotensinogen (AGT) through enzyme-linked immunoadsordent assay (ELISA) and analyzed its correlation with intrarenal renin–angiotensin system (RAS) activity in 128 chronic kidney disease (CKD) patients. Urinary and plasma renin activity, AGT, angiotensin II (Ang II) and aldosterone levels were also measured by radioimmunoassay (RIA) or ELISA in these participants. Further, the expression level of intrarenal renin, AGT, Ang II and Ang II receptors were examined by immunohistochemistry staining (IHCS) in 72 CKD patients. Their correlations with urinary AGT were also analyzed. We found that the urinary AGT level was positively correlated with hypertension (ρ = 0.28, P < 0.01), urinary protein (r = 0.38, P < 0.01), urinary Ang II (r = 0.29, P < 0.05), urinary type IV collagen (Col IV) (r = 0.56, P < 0.01), and was negatively correlated with estimated glomerular filtration rate (eGFR) (r = ?0.28, P < 0.01), urinary sodium (r = ?0.22, P < 0.05) and serum AGT (r = ?0.27, P < 0.01). Multiple regression analysis indicated low serum AGT (P < 0.01), high urinary protein (P < 0.01), high urinary Ang II (P < 0.05) and high urinary Col IV (P < 0.01) were correlated significantly with high urinary AGT. Urinary AGT level was positively correlated with intrarenal expression level of AGT (ρ = 0.46, P < 0.01), Ang II (ρ = 0.56, P < 0.01) and Ang II type 1 receptor (ρ = 0.32, P < 0.01), as detected by IHCS. Together, these data suggest that urinary AGT might be a potential biomarker of intrarenal RAS and Ang II activities in CKD patients.  相似文献   

12.
In this review we collected data on the length at maturity (Lm) and maximum reported total length (Lmax) of 565 Mediterranean marine fish stocks, representing 150 species, 68 families, 24 orders and 3 classes. Overall, Lm ranged from 2 cm, for the males of the toothcarp Aphanius fasciatus, to 350 cm, for the females of the bluntnose sixgill shark Hexanchus griseus. Lm was positively linearly related with Lmax for Actinopterygii (logLm = ?0.123 + 0.92 × logLmax; r 2 = 0.87, n = 471, P < 0.001) and Elasmobranchii (logLm = ?0.008 + 0.922 × logLmax; r 2 = 0.90, n = 92, P < 0.001) with the two slopes being significantly different (ANCOVA: F = 2,904, P < 0.001). The reproductive load (Lm/Lmax) ranged between 0.23 (sand steenbras Lithognathus mormyrus) and 0.94 (angular roughshark Oxynotus centrina and thornback ray Raja clavata). The mean Lm/Lmax was significantly (ANOVA, F = 34.14, P < 0.001) lower for Actinopterygii (mean = 0.59, SD = 0.122, n = 471) compared to Elasmobranchii (mean = 0.70, SD = 0.132, n = 92) and Holocephali (mean = 0.77, SD = 0.077, n = 2). The Lm/Lmax was significantly (ANOVA, F = 43.80, P < 0.001) higher for species providing some form of parental care, i.e. guarders, bearers, nesters (mean Lm/Lmax ± SD = 0.68 ± 0.141, n = 111) compared to non-guarders (mean Lm/Lmax ± SD = 0.59 ± 0.123, n = 454). The mean Lm/Lmax displayed a remarkable constancy with longitude (northern and southern Mediterranean coastline: ANOVA, F = 0.01, P = 0.93), latitude (western, central and eastern regions: ANOVA, F = 1.25, P = 0.29) and habitat (ANOVA, F = 0.85, P = 0.51).  相似文献   

13.
Vascular endothelial growth factor (VEGF) is important factor for angiogenesis in psoriasis. Methotrexate and psoralen and ultraviolet light A (PUVA) mainly target the T cell-mediated immunopathology of psoriasis. Our work aimed at estimating VEGF mRNA in psoriatic patients and investigating whether the standard therapeutic modalities (methotrexate and PUVA) exert their antiangiogenic activity through altering VEGF levels. Twenty-four chronic plaque psoriasis patients were enrolled. Patients were divided into two groups (12 patients each); group A received intramuscular methotrexate and group B was treated by PUVA three times/week in a PUVA 1000 cabin for 10 weeks each. Twelve healthy volunteers served as controls. A skin biopsy was taken from lesional skin before and after treatment for RT-PCR detection of VEGF mRNA. Capillary perfusion scanning using LASER Doppler perfusion imaging was performed on the same psoriatic plaque before and after treatment and was also done for the controls. Following both methotrexate and PUVA, a significant reduction in the amount of VEGF mRNA (P < 0.001 and P = 0.002, respectively) and capillary perfusion (P = 0.002) occurred. These reductions were significantly higher in the methotrexate group (P < 0.001 and  P = 0.001, respectively) than in the PUVA group. The percentage of clinical improvement in the examined psoriatic plaque was significantly positively correlated with the percentage of reduction in the amount of VEGF mRNA (r = 0.850, P < 0.001) and the percentage of reduction in the capillary perfusion (r = 0.684, P < 0.001). Both modalities may exert an antiangiogenic effect. Methotrexate appears to have possibly a more potent antiangiogenic effect than PUVA.  相似文献   

14.
Population estimates, often difficult to acquire, warrantee the use of an index as an economical substitute for rapid assessments of populations. We estimated population size of the little known social, semi-fossorial Indian desert jird (Meriones hurrianae) in Kachchh, Gujarat, India under closed population capture-mark-recapture (CMR) framework to calibrate a burrow count index for the species. A total of 147 individuals were trapped in 16 colonies using baited Sherman traps and the number of burrow entrances at each colony was recorded. Data from colonies with low number of captures were pooled to estimate capture probability using Huggins heterogeneity models with gender, site, body weight and age category as covariates in Program MARK. Colony sizes ranged from 2 to 46 individuals. The number of burrow entrances was calibrated against CMR-based population estimates using least squares regression (n = 16, adjusted R 2 = 0.96, t = 18.18, P < 0.001). The index was further validated using Jackknife (JK) analysis where JK-predicted population estimates strongly correlated with CMR estimates (r = 0.96, P < 0.001). In habitats and climatic conditions similar to Kachchh and within the range of colony sizes sampled, our calibrated index can be a valuable and effective tool for large scale surveys of the desert jird, which occupies a keystone trophic level in the semi-arid ecosystem.  相似文献   

15.
Iron and aluminum (oxyhydr)oxides are ubiquitous in the soil environment and have the potential to strongly affect the properties of dissolved organic matter. We examined the effect of oxide surfaces on soluble nutrient dynamics and microbial community composition using an incubation of forest floor material in the presence of (1) goethite and quartz, (2) gibbsite and quartz, and (3) quartz surfaces. Forest floor material was incubated over a period of 154 days. Aqueous extracts of the incubations were harvested on days 5, 10, 20, 30, 60, 90, and 154, and concentrations of P, N, PO4 3?, NO2 ?, NO3 ?, and organic C were measured in the solutions. Microbial community composition was examined through pyrosequencing of bacterial and fungal small subunit ribosomal RNA genes on selected dates throughout the incubation. Results indicated that oxide surfaces exerted strong control on soluble nutrient dynamics and on the composition of the decomposer microbial community, while possibly having a small impact on system-level respiration. Goethite and gibbsite surfaces showed preferential adsorption of P-containing and high molar mass organic solutes, but not of N-containing compounds. On average, organic C concentrations were significantly lower in water extractable organic matter (WEOM) solutions from oxide treatments than from the control treatment (P = 0.0037). Microbial community composition varied both among treatments and with increasing time of incubation. Variation in bacterial and fungal community composition exhibited strong-to-moderate correlation with length of incubation, and several WEOM physiochemical characteristics including apparent (weight averaged) molar mass, pH and electrical conductivity. Additionally, variation in bacterial community composition among treatments was correlated with total P (r = 0.60, P < 0.0001), PO4 3? (r = 0.79, P < 0.0001), and organic C (r = 0.36, P = 0.015) concentrations; while variation in fungal communities was correlated with organic C concentrations (r = ?0.48, P = 0.0008) but not with phosphorus concentrations. The relatively small impact of oxide surfaces on system-level microbial respiration of organic matter despite their significant effects on microbial community composition and WEOM dynamics lends additional support to the theory of microbial functional redundancy.  相似文献   

16.
Abstract

This study evaluated the effect of temperature on morphometric features of the egg during the embryonic development of the prawn Macrobrachium americanum and the relationship with hatching and the survival of the larvae. Berried females were grouped (n = 3) and reared at three different temperatures, 26, 29, and 33 °C, for which seven developmental stages were recognized. At each stage, the apical and sagittal diameters of the eggs were measured, the volume was calculated, and the weights were recorded. Additionally, the duration of embryonic development, hatching percentage, and larval survival were determined. At 29 and 33 °C, the eggs’ volume increased by 50%, but at 26 °C, the increase was 25%. Larvae from eggs incubated at 33 °C died one day after hatching. At 29 °C, larvae survived until Zoea VII. Larvae from eggs incubated at 26 °C died at the end of Zoea I. The number of days of embryonic development was 20.5 ± 1.5 (26 °C), 15 ± 1 (29 °C), and 12 ± 1 (33 °C). A temperature of 29 °C was the most favorable for embryonic development in M. americanum.  相似文献   

17.
The influence of forest fragmentation (habitat isolation) on biological and ecological diversity of aquatic insects was investigated in streams of fragmented forests in Hulu Gombak (6 streams) and Gunung Angsi (5 streams) and un-fragmented forest of Berembun (6 streams) in peninsular Malaysia. Several environmental parameters including canopy cover, DO, temperature and pH differed significantly among the three catchments (P < 0.05). We found that taxonomic richness in Berembun forest was significantly different from Gunung Angsi (P < 0.05), but not with Hulu Gombak forests (P > 0.05). Nestedness pattern that measures the effect of habitat isolation on taxonomic assemblages showed that aquatic insect’s community in un-fragmented forest (Berembun) was less nested (T = 54.4), indicating high diversity compared to highly nested (less diverse) in the two fragmented forests (Hulu Gombak, T = 30.45 and Gunung Angsi, T = 35.45). Taxa similarity in Berembun streams was negatively correlated with the geographical distance among streams (Mantel test, r = ? 0.462, P < 0.05). Such correlation was absent in both Gunung Angsi and Hulu Gombak streams. Forest fragmentation in Hulu Gombak and Gunung Angsi measured as the distance of the forests from the nearest forested area had negative effect on aquatic insects diversity (r 2 = ? 0.149, P < 0.05), but not on their abundances (r 2 = 0.003, P > 0.05). We concluded that local habitat conditions were the most important in shaping the aquatic insects community among streams of both unfragmented and fragmented forests.  相似文献   

18.
Although iron is a first-line pro-oxidant that modulates clinical manifestations of various systemic diseases, including diabetes, the individual tissue damage generated by active oxidant insults has not been demonstrated in current animal models of diabetes. We tested the hypothesis that oxidative stress is involved in the severity of the tissues injury when iron supplementation is administered in a model of type 1 diabetes. Streptozotocin (Stz)-induced diabetic and non-diabetic Fischer rats were maintained with or without a treatment consisting of iron dextran ip at 0.1 mL day?1 doses administered for 4 days at intervals of 5 days. After 3 weeks, an extensive increase (p < 0.001) in the production of reactive oxygen species (ROS) in neutrophils of the diabetic animals on iron overload was observed. Histological analysis revealed that this treatment also resulted in higher (p < 0.05) tissue iron deposits, a higher (p < 0.001) number of inflammatory cells in the pancreas, and apparent cardiac fibrosis, as shown by an increase (p < 0.05) in type III collagen levels, which result in dysfunctional myocardial. Carbonyl protein modification, a marker of oxidative stress, was consistently higher (p < 0.01) in the tissues of the iron-treated rats with diabetes. Moreover, a significant positive correlation was found between ROS production and iron pancreas stores (r = 0.42, p < 0.04), iron heart stores (r = 0.54, p < 0.04), and change of the carbonyl protein content in pancreas (r = 0.49, p < 0.009), and heart (r = 0.48, p < 0.02). A negative correlation was still found between ROS production and total glutathione content in pancreas (r = ?0.50, p < 0.03) and heart (r = ?0.45, p < 0.04). In conclusion, our results suggest that amplified toxicity in pancreatic and cardiac tissues in rats with diabetes on iron overload might be attributed to increased oxidative stress.  相似文献   

19.
Morphology can contain valuable information about the ecological performance of reef fishes, but it has rarely been used in combination with social traits. Social behavior is known to influence the ecological role of fishes; however, the ecological basis for pairing in reef fishes is not well understood. Field observations of 2,753 individuals, in 47 species in six families of biting reef fishes (Acanthuridae, Chaetodontidae, Kyphosidae, Labridae, Pomacanthidae, Siganidae), were used in combination with six morphological measurements, to examine the morphology of fishes in different social systems. A principal components analysis of morphological traits segregated species with high proportions of pairing individuals from non-pairing species along principal component 1, explaining 40.8 % of the variation. Pairing species were characterized by large eyes, concave foreheads, pointed snouts, deep bodies, and small maximum sizes. There was a significant positive relationship between these morphological traits (i.e., scores on PC1) and the prevalence of pairing within the Chaetodontidae (r 2 = 0.59; P = 0.026), Siganidae (r 2 = 0.72; P = 0.004), and Acanthuridae (r 2 = 0.82; P < 0.001). This was consistent when traits were corrected for phylogenetic effects. No pattern was evident in the scarine Labridae (r 2 = 0.15; P = 0.17). The morphological characteristics found among pairing species suggest that pairing species share common ecological traits, including foraging for small prey items in micro-topographically complex environments such as reef crevices. These ecological traits may have played a role in the evolution of pairing behavior and subsequently led to the development of reproductive patterns based on monogamy.  相似文献   

20.
As a zinc-finger protein, PR domain containing 16 (PRDM16) controls brown fat determination by stimulating brown fat-selective genes expression while suppressing the expression of genes selective for white fat cells, whose mutations were associated with myelodysplastic syndrome (MDS) and leukemogenesis in human and murine model of leukemia. To date, no polymorphisms of PRDM16 gene in bovine had been reported. Herein, PCR-SSCP and DNA sequencing methods were employed to screen the genetic variation within PRDM16 gene in 1031 Chinese indigenous bovine. The results revealed two novel silent mutations: XM_001788152: m.1641T>C (547aa), 1881G>A (627aa). Hence, we described the PvuII and HaeIII forced PCR–RFLP methods for detecting these mutations, respectively. In the forced PCR–RFLP analysis with PvuII, the frequencies of bovine PRDM16-C allele varied from 0.044 to 0.506 in four Chinese native breeds. In the forced PCR–RFLP analysis with HaeIII, the frequencies of bovine PRDM16-G allele were 0.474, 0.494, 0.576 and 0.906 for Jiaxian (JX), Nanyang (NY), Qinchuan (QC) and Chinese Holstein (CH) population. Significant statistical differences between genotypic frequencies implied that both of the polymorphic loci were significantly associated with cattle breeds by the chi square test (χ2 = 190.058, P < 0.001 and χ2 = 118.239, P < 0.001 for PvuII; χ2 = 209.842, P < 0.001 and χ2 = 108.711, P < 0.001 for HaeIII). The associations of the PvuII and HaeIII forced PCR–RFLPs of bovine PRDM16 loci with growth traits were analyzed in Nanyang breed. The two SNPs were associated with body weight and average daily gain in Nanyang aged 12 months, individuals with genotype TT and AA showed significantly better body weight (P < 0.05) and average daily gain (P < 0.01) at 12 months, respectively.  相似文献   

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