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1.
The influence of temperature on the diurnal activity of five species of aphidophagous lady beetles (Coleoptera: Coccinellidae) was investigated between 0700 and 1900 h in chili (Capsicum annuum L.) agroecosystems and neighboring vegetation (goose grass, Eleusine indica L.). The lady beetle species observed were Menochilus sexmaculatus Fabricius, Coelophora inaequalis F., Coccinella transversalis F., Harmonia octomaculata F. and Coelophora bissellata Mulsant. More lady beetles (of all species) were found during cooler periods (at 0700, 0900, 1100, and 1900 h). The diurnal pattern of lady beetle adult was temperature dependent. On chili plants, numbers were higher at temperatures between 22 to 30 °C (at 0700, 0900, 1100 and 1900 h) and numbers decreased when temperatures were above 30 °C. When temperature was above 30 °C under the chili plant canopy, numbers were higher in neighboring goose grass, where temperatures were cooler (< 30 °C). Numbers of all species were negative correlated between chili plant and goose grass.  相似文献   

2.
O6-Methylguanine-DNA methyltransferase (MGMT) repairs DNA damage caused by alkylating agents including N-nitroso compounds from diet. MGMT Ile143Val polymorphism may lead to less DNA damage repair and increased cancer risk depending on the environmental exposures. We investigated interactions between dietary factors and the MGMT Ile143Val polymorphism in relation to breast, colorectal and prostate cancer risk. There were 276/1498, 273/2984 and 312/1486 cases/controls for the breast, colorectal and prostate cancer studies respectively; all nested within the EPIC-Norfolk study, a prospective cohort of approximately 25,000 men and women aged 40–79. Baseline 7-day food diary data were collected for dietary assessment. MGMT Ile143Val polymorphism was not overall associated with breast, colorectal and prostate cancer risk. There was a significant interaction between this polymorphism and intake of red and processed meat on colorectal cancer risk (Pinteraction = 0.04) suggesting an increased risk among carriers of the variant genotype compared to the MGMT Ile143Ile common genotype. A lower colorectal cancer risk was seen with higher intake of vitamin E and carotene among the variant genotype group but not in the common genotype group (Pinteraction = 0.009 and Pinteraction = 0.005 for vitamin E and carotene, respectively). A higher prostate cancer risk was seen with higher alcohol intake among the variant genotype (OR = 2.08, 95% CI = 1.21–3.57, Pinteraction = 0.0009) compared to the common genotype with lower alcohol intake. In this UK population, the MGMT Ile143Val polymorphism was not overall associated with breast, colorectal and prostate cancer risk. There was evidence for this polymorphism playing a role in modulating the risk of prostate cancer in presence of alcohol. For colorectal cancer, the MGMT Ile143Val polymorphism may confer increased or decreased risk depending on the dietary exposure.  相似文献   

3.
1. We measured oxygen consumption of seven juvenile Northern water snakes, Nerodia sipedon, at 3, 19, 41, and 89 h after feeding. 2. Oxygen consumption 19 h after eating was significantly higher than at 3, 41, and 89 h after feeding and the values at 3 h post-feeding were significantly higher than those at 41 and 89 h. 3. We monitored substrate temperature preference in nine juvenile N. sipedon at 2000, 0000, 0800, 1200, and 1600 h for 3 days. 4. After feeding and at night snakes selected warmer substrate temperatures.  相似文献   

4.
《Small Ruminant Research》2007,68(2-3):264-270
The objective of the present study was to compare live animal performance and carcass characteristics of 3/4 or 7/8 Dorper (DO; n = 30), purebred Katahdin (KA; n = 20), purebred St. Croix (SC; n = 17) and purebred Suffolk (SU; n = 10) lambs born in the spring and fall of 2001. After weaning, lambs were supplemented with up to 680 g of a corn-soybean meal supplement while grazing bermudagrass pastures overseeded with ryegrass. Lambs were slaughtered at approximately 210 d of age. From birth to weaning, DO lambs gained faster (P < 0.001) than KA or SC lambs, whereas KA lambs had higher (P < 0.001) ADG than SC lambs. Additionally, DO and SU wethers had greater (P < 0.02) ADG from weaning to slaughter than SC or KA wethers. Suffolk lambs were heavier (P < 0.001) at slaughter and produced heavier (P < 0.001) carcasses than lambs from hair-sheep breeds. Carcasses of KA lambs were fatter (actual fat thickness; P < 0.02) resulting in higher yield grades (P < 0.03) than carcasses of DO, SC, or SU lambs. Carcasses of DO and SU had larger (P < 0.001) longissimus muscle (LM) areas than those of KA or SC carcasses, whereas kidney fat weight and percentage were greater (P < 0.001) in carcasses from KA and SC than DO and SU lambs. Lean maturity was similar (P = 0.32) among breed-types. However, skeletal maturity was greater (P < 0.001) in SU than hair-sheep carcasses. Flank-streaking scores were similar (P = 0.19) among the breed-types, but conformation scores were higher (P < 0.001) for DO and SU carcasses and resulted in higher (P < 0.001) quality grades than SC carcasses. The LM of SU lambs was lighter (higher L* values; P < 0.05) than that of KA and SC lambs, whereas the LM from DO lambs was redder (higher a* values; P < 0.001) than SC and SU and more (P < 0.001) yellow than that of the other breed-types. Chops from SU lambs were tougher (higher shear force values; P < 0.007) than chops from the hair-sheep breeds. Results of this study indicate that ADG, carcass muscularity and meat quality were similar between DO and SU lambs, and, although fatter, carcass muscularity of KA was similar to that of DO lambs.  相似文献   

5.
Thermal stress in hot semi-arid environment is a major limitation of sheep production in tropical and sub-tropical climatic condition. The animals tend to maintain homeostasis through physiological adjustments in a hot environment (maximum temperature reaches up to 47.5 °C). Therefore, the present study was carried out to assess the effect of thermal exposure on physiological adaptability and seminal attributes of rams under semi-arid environment. The experiment was conducted for eight weeks involving sixteen Malpura crossbred rams (GMM: Garole X Malpura X Malpura). The rams were divided equally into two groups, designated as G1 and G2, respectively. The rams in G1 (Control) group were kept in a sheep shed under naturally prevailing environment without artificial manipulation of ambient temperature (Temperature 30.48±0.38 °C; Relative Humidity 28.59±1.15%). The rams of G2 group were exposed to different temperature at different hours of the day (38 °C at 1000–1100 h; 40 °C at 1100–1200 h; 42 °C at 12:00–1300 h; 43 °C at 1300–1400 h; 44 °C at 1400–1500 h and 42 °C at 1500–1600 h) in a climatic chamber for thermal exposure. Physiological responses, blood biochemical profile, blood endocrine profile, sexual behavior and seminal attributes were measured for both the groups. Thermal exposure significantly (P<0.05) increased the water intake; respiration rate, rectal temperature and skin temperature at afternoon in rams. Exposure of rams to thermal stress (G2) significantly (P<0.05) increased cortisol level and decreased tri-ido-thyronine level. The latency period after the first ejaculation, decreased significantly (P<0.05) in G2. The percentage of rapid motile sperm, linearity and average path velocity of sperm were also altered significantly (P<0.05) in thermal exposed rams as compared to control. However, comparable feed intake, body weight, and major blood biochemical parameters, as well as acceptable semen quality attributes of all the rams indicated that the Fec B gene introgressed Malpura cross rams adapted to the thermal exposure under semi-arid tropical climate.  相似文献   

6.
Glutathione S-transferases (GSTs) genetic variants have been explored extensively as a predictive factor for cancer etiology. This meta-analysis aimed to examine the associations GSTM1, GSTT1, and GSTP1 genetic polymorphisms with thyroid cancer risk. PubMed, EMBASE, Cochrane Library, and HuGNet database were searched up to November 2011 using the appropriate terms. Twelve studies regarding GSTM1 null polymorphism (1569 cases and 2907 controls), 11 studies concerning GSTT1 null polymorphism (1515 cases and 2863 controls), and 8 studies on GSTP1 Ile105Val (965 cases and 1604 controls) were included in the meta-analysis. The random effects odds ratio was 1.07 (95% CI: 0.88–1.31; I2 = 54.1%, P for heterogeneity = 0.013) for the GSTM1 null vs. present genotype and 1.08 (95% CI: 0.75–1.57; I2 = 81.4%, P for heterogeneity < 0.001) for the GSTT1 null vs. present genotype, and 1.02 (95% CI: 0.70–1.49; I2 = 74.6%, P for heterogeneity < 0.001) for the GSTP1 Val/Val + Val/Ile vs. Ile/Ile genotype. Similarly, no significant associations were demonstrated for subgroup analyses performed by ethnicity and histological type. In conclusion, these three polymorphisms are unlikely to be major determinants of susceptibility to thyroid cancer. Reasons for potential heterogeneity of effects, which could include true biologic heterogeneity, publication bias, or chance, deserve further investigation. The relationship between these three genes and thyroid carcinoma must be evaluated further with gene–gene and gene–environment interactions.  相似文献   

7.
Background: Glutathione S-transferase (GST) enzymes are involved in electrophile detoxification. The authors investigated the association between GST genotype and survival in a racially diverse, population-based cohort of colorectal cancer (CRC) patients followed for a median of 9.6 years. Methods: Interviews were conducted with 315 African-American and White CRC patients in Connecticut, 1987–1991. Tumor tissue (n = 197) was later retrieved from hospital of diagnosis and assayed using multiplex PCR (GSTM1 and GSTT1) and PCR and RFLP analysis (GSTP1). Cox proportional hazards models provided adjusted hazard ratios (HR) and 95% confidence intervals (CI). Results: Individuals with Ile/Val or Val/Val GSTP1 genotypes had a decreased risk of death (multivariate adjusted HR = 0.72, 95% CI: 0.48, 1.09) relative to those with wild type (Ile/Ile). Among those who received chemotherapy, this benefit was more pronounced (HR = 0.35, 95% CI: 0.16, 0.79); the interaction of reduced function GSTP1 genotype and chemotherapy was significant (P = 0.05). GSTM1 and GSTT1 genotype were not associated with survival. GSTM1, GSTT1, and GSTP1 genotype did not vary by race and did not contribute significantly to the survival disadvantage observed in African-Americans. Conclusions: In summary, GSTP1 genotype may play a role in CRC survival in African-Americans and Whites, particularly among those who receive chemotherapy.  相似文献   

8.
An experiment was conducted to investigate the effects of feeding schedule on dry matter (DM), gross energy (GE), crude protein (CP), and amino acid (AA) digestibility by growing pigs. Six growing castrates (initial body weight: 40.5 ± 2.25 kg) were equipped with a T-cannula in the distal ileum and allotted to a repeated 3 × 3 Latin square design with three animals and three periods in each square. A maize–soybean meal based diet (181 g CP/kg) was formulated and fed to the pigs in three different feeding schedules; i.e., one meal per day, two meals per day, or free access to feed. Pigs fed one or two meals per day were allotted a daily amount of feed equivalent to three times the maintenance energy requirement. Fecal and ileal samples were collected from all pigs in each period. The coefficients of ileal apparent digestibility (CIAD) for DM, GE, CP, and AA were calculated as were the coefficients of total tract apparent digestibility (CTTAD) of DM and GE. Results of the experiment showed that there were no differences in the CIAD for DM, GE, or for any of the AA among the three feeding schedules. In contrast, pigs given free access to the diet had lower (P<0.002) CTTAD for DM and GE compared with pigs fed a restricted amount of feed either once or twice daily. Therefore, the concentration of digestible energy in the diet was lower if calculated from pigs given free access to the diet compared with pigs fed the diet once or twice daily (14.38 MJ/kg versus 14.83 MJ/kg and 15.13 MJ/kg). It is concluded that the feeding schedule does not influence the CIAD for DM, GE, CP, or AA by pigs. Therefore, any of the three feeding schedules that were used in the current experiment may be used in experiments aimed at measuring CIAD in pigs. However, if the CTTAD of DM and GE are measured, it is recommended that pigs are given free access to feed.  相似文献   

9.
This experiment investigated the preference of juvenile pigs for illuminance, and indirectly photoperiod, at two ages. The animals were equally familiar with all illuminances prior to testing. Four groups, each of four pigs, occupied a four-compartment preference chamber in which a different illuminance was applied to each compartment: minimum (2.4), 4, 40 and 400 lx. Illuminances were rearranged every 2 days to avoid positional bias. The pigs significantly preferred the dimmest illuminance (mean occupancy 7 h 20 min per 24 h, backtransformed data) and spent the least time in the brightest (4 h 49 min per 24 h), with an intermediate and similar length of time spent in the other illuminances (6 h 25 min and 5 h 25 min in 4 and 40 lx, respectively, F3,127 = 8.93, P < 0.001). The most common behaviours of the pigs when in the darkest compartment were resting and sleeping. The EU directive 2001/88 requires a minimum illuminance of 40 lx for pig production; this illuminance was neither aversive nor strongly preferred by the pigs. Our findings also suggest that pigs should be provided with an appropriate period of rest at an illuminance of 2.4 lx for at least 6 h per day. The only active behaviour affected by illuminance was defecation; the pigs preferred to defecate in the brighter illuminances. Spatial provision of minimal illuminance could potentially improve pig welfare by providing a preferred light environment for resting and also by creating a resting area distinct from dunging areas, thus improving hygiene.  相似文献   

10.
Rapidly cooling pigs after heat stress (HS) results in a pathophysiological condition, and because rapid temperature fluctuations may be associated with reduced reproductive success in sows, it lends itself to the hypothesis that these conditions may be linked. Objectives were to determine the effects of rapid cooling on thermal response and future reproductive success in pigs. Thirty-six replacement gilts (137.8±0.9 kg BW) were estrus synchronized and then 14.1±0.4 d after estrus confirmation, pigs were exposed to thermoneutral conditions (TN; n=12; 19.7±0.9°C) for 6 h, or HS (36.3±0.5°C) for 3 h, followed by 3 h of rapid cooling (HSRC; n=12; immediate TN exposure and water dousing) or gradual cooling (HSGC; n=12; gradual decrease to TN conditions) repeated over 2 d. Vaginal (TV) and gastrointestinal tract temperatures (TGI) were obtained every 15 min, and blood was collected on d 1 and d 2 during the HS and recovery periods at 180 and 60 min, respectively. Pigs were bred 8.3±0.8 d after thermal treatments over 2 d. Reproductive tracts were collected and total fetus number and viability were recorded 28.0±0.8 d after insemination. HS increased TV and TGI (P=0.01; 0.98 °C) in HSRC and HSGC compared to TN pigs. During recovery, TV was reduced from 15 to 105 min (P=0.01; 0.33 °C) in HSRC compared to HSGC pigs, but no overall differences in TGI were detected (P<0.05; 39.67 °C). Rapid cooling increased (P<0.05) TNFα compared to HSGC and TN pigs during recovery-d 1 (55.2%), HS-d 2 (35.1%), and recovery-d 2 (64.9%). Viable fetuses tended to be reduced (P=0.08; 10.5%) and moribund fetuses tended to be increased (P=0.09; 159.3%) in HSRC compared to HSGC and TN pigs. In summary, rapid cooling prior to breeding may contribute to reduced fetal viability and reproductive success in pigs.  相似文献   

11.
DNA and chromosome damages in peripheral blood lymphocytes were evaluated in 151 workers occupationally exposed to formaldehyde (FA) and 112 non-FA exposed controls. The effects of polymorphisms in three glutathione-S-transferase (GSTs) genes on the DNA and chromosome damages were assessed as well. Alkaline comet assay and cytokinesis-block micronucleus (CBMN) assay were used to determine DNA and chromosome damages, respectively. The genotypes of GSTP1 (Ile105Val), GSTT1, and GSTM1 were assayed. The mean 8-h time-weighted average (TWA) concentrations of FA in two plywood factories were 0.83 ppm (range: 0.08–6.30 ppm). FA-exposed workers had higher olive tail moment (TM) and CBMN frequency compared with controls (Olive TM, 3.54, 95%CI = 3.19–3.93 vs. 0.93, 95%CI = 0.78–1.10, P < 0.01; CBMN frequency, 5.51 ± 3.37 vs. 2.67 ± 1.32, P < 0.01). Olive TM and the CBMN frequency also had a dose-dependent relation with the personal FA exposure. Significant association between FA exposure history and olive TM and CBMN frequency were also identified. The level of olive TM was slightly higher in FA-exposed workers with GSTM1 null genotype than those with non-null genotype (3.86, 95%CI = 3.31–4.50 vs. 3.27, 95%CI = 2.83–3.78, P = 0.07) with adjustment of covariates. We also found that FA-exposed workers carrying GSTP1 Val allele had a slightly higher CBMN frequency compared with workers carrying only the wild-type allele (6.32 ± 3.78 vs. 5.01 ± 2.98, P = 0.05). Our results suggest that the FA exposure in this occupational population increased DNA and chromosome damages and polymorphisms in GSTs genes may modulate the genotoxic effects of FA exposure.  相似文献   

12.
The dual-functioning antioxidant enzyme peroxiredoxin VI (Prdx6) detoxifies lipid peroxides particularly in biological membranes, and its peroxidase function is activated by glutathione S-transferase Pi (GSTP). The GSTP gene is polymorphic in humans, with the wild-type GSTP1-1 A (Ile105, Ala114) and three variants: GSTP1-1B (Ile105Val, Ala114), GSTP1-1C (Ile105Val, Ala114Val), and GSTP1-1D (Ile105, Ala114Val). The focus of this study was to determine the influence of these polymorphisms on Prdx6 peroxidase function. Using extracellular generation of OH radicals and fluorescence (DPPP dye) detection, we found a fast (∼300 s) onset of lipid peroxidation in membranes of MCF-7 cells transfected with a catalytically inactive Y7F mutant of GSTP1-1 and either GSTP1-1B or GSTP1-1D. However, this effect was not detected in cells expressing either GSTP1-1A or GSTP1-1C. Imaging of DPPP-labeled MCF-7 cells showed fluorescence localized in the plasma membrane, but intensity was substantially diminished in the GSTP1-1 A- and GSTP1-1C-expressing cells. Moreover, in the Y7F mutant of GSTP1-1 A-, GSTP1-1B-, and GST1-1D-expressing cells OH generation resulted (after 36 h) in plasma membrane-permeability-related cell death, whereas GSTP1-1A- and GSTP1-1C-expressing cells had significantly better survival. We used FRET analyses to measure in vitro binding of purified GSTP1-1 allelic variant proteins to purified recombinant Prdx6. The affinities for Prdx6 binding to GSH-loaded GSTP1-1's either mirrored their observed peroxidase activities (using phospholipid hydroperoxide as a substrate), GSTP1-1A>GSTP1-1C (KD=51.0 vs 57.0 nM), or corresponded to inactivation, GSTP1-1B (GSTP1-1D) (KD=101.0 (94.0) nM). In silico modeling of the GSTP1-1–Prdx6 heterodimer revealed that the sites of GSTP1-1 polymorphism (Ile105 and Ala114) are in close proximity to the binding interface. Thus, there is a hierarchy of effectiveness for polymorphic variants of GSTP1-1 to regulate Prdx6 peroxidase function, a feature that may influence human population susceptibilities to oxidant stress.  相似文献   

13.
Two experiments were conducted to study the efficacy and causes of medium-chain triglycerides (MCT) in sow diet in improving the survival of neonatal pigs. In Experiment 1, beginning on d84 of gestation and continuing through d28 of lactation, 51 sows were fed corn–soybean meal diet mixed with either soybean oil (SO; n=17), coconut oil (CO; n=18), or MCT (n=16) in a proportion of 9 : 1 by weight. The highest improvement in survival of pigs by sows fed MCT (p<0.01) or CO (p<0.05) was observed during the first three days after birth in pigs weighing <1100 g at birth, compared with sows fed SO. Their three-day survival was 98.6, 80.0 and 47.6%, respectively, for MCT, CO and SO groups. In Experiment 2, beginning on d84 of gestation and continuing through farrowing, 24 sows, 8 sows per treatment, were fed diets as in Experiment 1. Liver glycogen content of pigs 4 h after born from sows fed MCT (p<0.10) and CO (p<0.01), and muscle glycogen of pigs from sows fed MCT (p<0.01) and CO (p<0.10) were increased, compared to those of pigs from sows fed SO. Plasma albumin was increased by MCT and CO (p<0.01), relative to SO. The results suggest that MCT or CO in sow diets may enhance the body glycogen stores and maturity of pigs at birth and, hence, their survival, particularly in pigs with low birth weight during the first three days of life.  相似文献   

14.
Two experiments (Exp.) were conducted to evaluate the effects of β-glucan inclusion in the diet on growth performance and immune function after lipopolysaccharide (LPS) challenge. In Exp. 1, a total of 40 weaned pigs (progeny of Landrace×Yorkshire sows by Duroc) with an initial body weight (BW) of 7.89 ± 0.84 kg (21 ± 2 d) of age) were used in a 28-day (d) experiment to determine the effects of dietary β-glucan on growth performance. Pigs were allotted randomly to two treatments consisting of addition of 0 or 0.1 g β-glucan/kg diet with four replicate pens per treatment and five pigs per pen. Growth performance was not affected by β-glucan supplementation throughout the experiment. However, dietary β-glucan reduced (P<0.05) the number of fecal Escherichia coli. In Exp. 2, a total of 20 weaned barrows (6.22 ± 0.25 kg of BW and 21 ± 2 d of age) individually raised in metabolic cages were used to evaluate immunological responses following LPS challenge. Pigs were fed 0 or 0.1 g β-glucan/kg diet for 42 d. At the end of the trial, half of the pigs (n = 5) from each treatment were injected intraperitoneal with E. coli LPS at a concentration of 100 μg/kg BW and the other half were injected with sterile saline solution. Treatments were arranged as a 2×2 factorial, with the main effect of LPS challenge (saline vs. LPS) and β-glucan supplementation (0 g/kg vs. 0.1 g/kg). After LPS injection, blood was taken at 0, 2, 4, 6, 8 and 12 hours (h) for the blood cell counts and blood inflammatory response. Dietary β-glucan increased (P<0.05) leukocytes counts at 4, 6 and 8 h, and blood lymphocyte concentrations at 2, 4 and 6 h and LPS challenge increased (P<0.05) counts of leukocytes at 2, 4, 6 and 8 h and blood lymphocyte at 2 and 4 h post-challenge. The rectal temperature was increased (P<0.05) at 2, 4, 6 and 8 h after LPS challenge. Dietary β-glucan reduced (P<0.05) and LPS challenge increased (P<0.05) blood plasma tumor necrosis factor-α (TNF-α) concentration at 2 and 4 h post-challenge. Dietary β-glucan increased (P<0.05) the concentration of the cluster of differentiation antigens 4 cells (CD4+) at 2, 4 and 6 h, and of 8 (CD8+) at 4 and 6 h post-challenge, respectively. The LPS challenge increased (P<0.05) CD4+ and CD8+ cell concentrations at 2, 4 and 6 h post-challenge. The CD4+:CD8+ ratio was reduced (P<0.05) by LPS challenge but was increased (P<0.05) by dietary β-glucan at 2, 4, 6 and 8 h post-challenge. In conclusion, dietary β-glucan decreased E. coli numbers but did not affect growth performance in weaned pigs and may offer benefits on immune function in weaned pigs challenged with LPS.  相似文献   

15.
Background: A complex of genetic and environmental factors is involved in carcinogenesis of the esophageal squamous cell carcinoma (ESCC). Glutathione-S-Transferases (GSTs) are phase-II enzymes playing role in detoxification of carcinogen electrophiles. Genetic polymorphisms of GSTM1, GSTT1 and GSTP1 in association with some environmental factors and their impact on esophageal cancer susceptibility were assessed in the Iranian population. Methods: Genomic DNA of peripheral blood leukocytes from 148 confirmed esophageal cancer cases and 137 healthy individuals as control group was assayed for restriction fragment length polymorphisms in the GSTP1 loci by PCR amplification followed by digestion with Alw26I. Deletion of the GSTM1 and GSTT1 genes was detected by multiplex PCR. A data-mining method based on decision trees was applied to produce a predictive model of interactions between genotypes. Results: Smoking was independently associated with ESCC (p < 0.05, OR: 2.286, 95% CI = 1.311–3.983). Smoking along with GSTP1 Val/Val genotype was associated to ESCC (p < 0.001, OR: 3.886, 95% CI = 1.830–8.251), while non-smokers with GSTP1 Val/Val were significantly more frequent in non-cancerous group. (p = 0.007, OR: 0.507, 95% CI = 0.309–0.830). Conclusions: Data-mining methods are useful tools to map out a scheme for predicting complex relations and combinations of different genotypes. Genotyping analysis of GSTP1 together with assessment of smoking seems to be important in determining the risk of ESCC in the Iranian population.  相似文献   

16.
The objective of this study was to evaluate the effect of sex composition of the group of lambs before puberty on later sexual performance in Awassi ram lambs. Thirteen Awassi ram lambs of the same age were raised in either all-male group (n = 7) or in a group mixed with females (n = 6) from weaning to puberty. Blood samples, body weights (BW) and scrotal circumferences (SC) of ram lambs were recorded between eight and 10 months of age. Sexual performance testing was performed at 9 months of age by individually exposing ram lambs to oestrous females on five occasions. Body weight and SC were greater (P < 0.01) in the all-male compared with the mixed group. Plasma testosterone concentrations were not influenced (P > 0.05) by treatment. Plasma testosterone concentrations were significantly correlated (P  0.05) with BW (r = 0.3) and SC (r = 0.4). No treatment effects were detected regarding bouts of leg-kicking. Bouts of anogenital sniffing, the frequency of mount attempts and mounting frequency were greater (P < 0.05) in the all-male group. Even though the frequency of raising the fat tail of females was similar between the two treatments, the mixed group tended to be (P = 0.08) more efficient in doing so than the all-male group (higher tail raising/mount). Results of the current study indicate that mixing groups of ram and ewe lambs before puberty may be insufficient to improve later sexual performance of ram lambs.  相似文献   

17.
18.
BackgroundGlucagon-like peptide-2 (GLP-2) is known to increase mesenteric blood flow. The aim of the study was to evaluate the effect of GLP-2 on blood flow in different vascular sites, and dynamic changes in cardiac parameters.Methods10 healthy volunteers were given 450 nmol subcutaneous (SC) GLP-2 or isotonic saline (5 subjects) in a single blinded manner. During the following 90 min, blood flow in the superior mesenteric artery (SMA), celiac artery (CA), renal artery (RA), common carotid artery (CCA) was measured using Doppler ultrasound (US), and cardiovascular variables were measured by impedance cardiography and finger plethysmography. Plasma GLP-2 was measured at times 0, 30 and 60 min.ResultsCompared to the placebo group, GLP-2 elicited a 27% decrease in the resistance index (RI) and a 269.4% increase in Time Averaged Maximal Velocity (TAMV) in the SMA (P < 0.01). CA, RA and CCA: There were no significant changes in RI or TAMV in the GLP-2 or placebo group, and no change in CA diameter.Cardiac parameters: GLP-2 increased cardiac output (CO), stroke volume (SV) and heart rate (HR) compared to baseline (respectively: 15.3, 4.81 and 8.2% (P < 0.001, P < 0.01 and P < 0.01)). The CO, SV and HR changes were not significantly different from the placebo group.Mean plasma GLP-2 serum levels in the placebo group at times 0, 30 and 60 min were 22.8, 23.4 and 23.2 pmol/l. In the GLP-2 group 20.3, 1273 and 1725 pmol/l.ConclusionSC GLP-2 increased SMA blood flow, as previously shown, but elicited no changes in other vascular sites. CO and HR increased significantly, presumably due to the increased mesenteric blood flow.  相似文献   

19.
AimsThis study was conducted to investigate the associations between single nucleotide polymorphisms (SNPs) of matrix metalloproteinases (MMPs) and Kawasaki disease (KD) in the Korean population.Main methodsA total 0f 101 KD patients and 306 healthy controls were examined. MMP7 (rs10502001, G/A, Arg77His), MMP11 (rs738792, T/C, Ala38Val), MMP12 (rs652438, A/G, Ile357Val) and MMP26 (rs2499953, A/G, Lys43Glu) genes were genotyped from the genomic DNA using direct sequencing. The results were then analyzed using logistic regression models, adjusting for gender as covariates.Key findingsThe four SNPs were in Hardy–Weinberg equilibrium. Only the MMP11 polymorphism (rs738792) was associated with KD. The SNP (rs738792) showed a statistically significant association with KD in the codominant (OR = 1.61, 95% CI = 1.11–2.34, P = 0.011) and dominant (OR = 1.92, 95% CI = 1.21–3.06, P = 0.006) models. However, there was no association between polymorphisms of other MMP genes and KD.SignificanceOverall, the results of this study indicate that MMP11 polymorphism may be associated with KD in the Korean population.  相似文献   

20.
《Process Biochemistry》2014,49(1):25-32
The compound 1,2,4-butanetriol (BT) is a valuable chemical used in the production of plasticizers, polymers, cationic lipids and other medical applications, and is conventionally produced via hydrogenation of malate. In this report, BT is biosynthesized by an engineered Escherichia coli from d-xylose. The pathway: d-xylose  d-xylonate  2-keto-3-deoxy-d-xylonate  3,4-dihydroxybutanal  BT, was constructed in E. coli by recruiting a xylose dehydrogenase and a keto acid decarboxylase from Caulobacter crescentus and Pseudomonas putida, respectively. Authentic BT was detected from cultures of the engineered strain. Further improvement on the strain was performed by blocking the native d-xylose and d-xylonate metabolic pathways which involves disruption of xylAB, yjhH and yagE genes in the host chromosome. The final construct produced 0.88 g L−1 BT from 10 g L−1 d-xylose with a molar yield of 12.82%. By far, this is the first report on the direct production of BT from d-xylose by a single microbial host. This may serve as a starting point for further metabolic engineering works to increase the titer of BT toward industrial scale viability.  相似文献   

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