SMT-738: a novel small-molecule inhibitor of bacterial lipoprotein transport targeting Enterobacteriaceae.

Carbapenem-resistant Enterobacteriaceae (CREs) are described by the Centers for Disease Control as an urgent threat, and there is a critical need for new therapeutic agents able to treat infections caused by these pathogens. Herein, we describe the microbiological profile, the mechanism f action, and the in vitro safety as well as the pharmacokinetic (PK)/PD profile of SMT-738, a small molecule belonging to a new chemical class. SMT-738 is active against Enterobacterales [including multi-drug-resistant Escherichia coli with 90% of isolates having a minimum inhibitory concentration (MIC90) of 1 µg/mL and Klebsiella pneumoniae 2 µg/mL] and inactive against a broad panel of Gram-negative and Gram-positive pathogens. SMT-738 displays rapid bactericidal activity (2-4 h) and has a low propensity for resistance development (less than ~10-9). Characterization of resistant mutants following exposure to SMT-738 identified mutations within the lipoprotein transport complex (LolCDE), a clinically unexploited and essential bacterial molecular target in Gram-negative bacteria. SMT-738 has a promising in vitro toxicology profile. Furthermore, PK studies demonstrated that when dosed intravenously, SMT-738 maintained exposure levels across infection sites (bloodstream/urinary tract/lung). Proof-of-concept studies across multiple murine in vivo infection models (bloodstream/pneumonia/urinary tract) demonstrated that SMT-738 significantly reduced the bacterial burden compared to baseline and vehicle control. SMT-738 represents a promising novel drug candidate being developed to address clinically challenging serious life-threatening infections caused by highly resistant Enterobacteriaceae including CRE.

[Current status and development trend of vascular compressive therapy].

As a non-invasive and safe physical therapy modality, compressive therapy plays an indispensable role in the treatment of vascular diseases and wounds. However, the concept of compressive therapy has not been widely adopted at present. And there are also problems such as non-standard treatment methods and inconsistent standards of pressure devices. Therefore, it is urgent to improve the standard system of compressive therapy, improve the level of diagnosis and treatment of related diseases, and promote the further development of compressive therapy.

Biological Characteristics and Genetic Diversity of Phomopsis asparagi, Causal Agent of Asparagus Stem Blight.

Asparagus stem blight is a regional disease. In the present study, we compared strains of Phomopsis asparagi from six different provinces to determine their biological characteristics and genetic diversity, differences in the pycnidium and conidium production, pathogenicity, and growth rate. Considerable differences were established in the pycnidium and conidium production among the P. asparagi strains from the six studied provinces. The largest pycnidium and conidium production had the strains from Fujian, followed by those from Hainan. The virulence of P. asparagi strains was significantly different but without a correlation with the geographical source of the strain. FJ2 had the highest virulence, followed by HN2, SD4, and SD5, whereas SD5 had the lowest virulence. The colony diameter and dry weight of the strains of asparagus stem blight fungus from the six provinces were substantially different. The colonies of HN1-5 had the largest diameters, whereas those of XT1-5, LT1-3, FJ1-5, and SX6 had smaller diameters. Four primers with good repeatability and strong specificity were selected from 100 intersimple sequence repeat (ISSR) primers. ISSR-PCR amplification was performed on 36 strains of asparagus stem blight fungus, and a large number of repeatable DNA fingerprints were obtained. Most of the amplified fragments were within 300 to 500 bp. In all, 69 total points, 64 multiple points, and 92.75% polymorphism points were established. The number of ISSR gene sites detected by four primers ranged from 14 to 20, with an average of 16 multiple sites. The copolymerization was divided into three groups: XT1-5, LT1-3, and FJ1-5, which were clustered into the first group; SD1-6, SX1-6, and HB1-6, clustered into the second group; and HN1-5 in the third group. The results of the cluster analysis revealed that the strains of the neighboring provinces had a nearer phylogenetic relationship than that between distant ones. Therefore, the system evolution of P. asparagi is related to the geographical distribution of its strains.

[The effects of continuous proton pump inhibitor therapy on small intestinal bacterial overgrowth in elderly].

Objective: Long-term proton pump inhibitor(PPI) therapy may increase the risk of small intestinal bacterial overgrowth(SIBO). Few studies on the effect of on-demand and continuous PPI therapy are available in elderly. To investigate the prevalence of SIBO and the effect of on-demand and continuous PPI therapy on SIBO in elderly. Methods: A total of 200 elderly outpatients admitted to Department of Gastroenterology at the Second Medical Center of PLA General Hospital were enrolled and divided into 3 groups: continuous PPI group, on-demand PPI group and control group. SIBO was diagnosed according to methane and hydrogen lactulose breath test (LBT).The prevalence of SIBO in the 3 groups was analyzed. Results: The prevalence of SIBO was 71.5% in 200 elderly. PPI therapy and diabetes mellitus (DM) were independent risk factors for SIBO. The prevalence of SIBO was 77.1% (108/140) in elderly who underwent long-term PPI therapy and 58.3% (35/60) in those without PPI therapy (P<0.01).The prevalence of SIBO was significantly higher in continuous PPI therapy group than that in on-demand PPI group and control group(88.6% vs. 65.7% and 58.3%, all P<0.01).However, no significant difference was found in the prevalence of SIBO between on-demand PPI group and control group (P>0.05). In elderly who underwent long-term PPI therapy, the prevalence of SIBO increased significantly if administration time was longer than 61 months. Conclusions: SIBO usually occurs in elderly patients who receive continuous PPI rather than on-demand use. If elderly require long-term PPI therapy, on demand administration is suggested as long as primary diseases are properly treated.

Prediction of prostate cancer aggressiveness with a combination of radiomics and machine learning-based analysis of dynamic contrast-enhanced MRI.

AIM: To investigate whether the combination of radiomics and automatic machine learning-based classification of original images from multiphase dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) can predict prostate cancer (PCa) aggressiveness before biopsy. MATERIALS AND METHODS: Forty consecutive biopsy-confirmed PCa patients were included. Biopsy was performed within 4 weeks after the DCE-MRI examinations. According to the time-signal-intensity curve, lesion segmentation was performed on the first and on the strongest phase of the enhancement on the original DCE-MRI images, and 1,029 quantitative radiomics features were calculated automatically from each lesion, wherein there were three datasets available (Dataset-F, Dataset-S and Dataset-FS). The variance threshold method, select k-best method and least absolute shrinkage and selection operator (LASSO) algorithm were used to reduce the feature dimensions. Five machine learning approaches leveraging cross-validation were employed, and the clinical value of each model was evaluated by area under the receiver operating characteristic curve (AUC). Correlation analysis was performed between the features of the machine learning model that achieved the best classification performance and the Gleason score (GS) of the PCa lesion. RESULTS: Eight, four, and 16 features were selected as optimal subsets in Dataset-F, -S and -FS, respectively. Among all three datasets, logistic regression (LR)-based analysis with Dataset-FS had the highest predication efficacy (AUC=0.93). Ten features in Dataset-FS showed significantly positively correlation with GS. The model performance of Dataset-F was generally better than that in Dataset-S. CONCLUSIONS: A combination of radiomics and machine learning-analysis based analysis of the union of the first and strongest phases of original DCE-MRI images can predict PCa aggressiveness non-invasively, accurately, and automatically.

Danshen (Salvia miltiorrhiza) protects ovariectomized rats fed with high-saturated fat-sucrose diet from bone loss.

Dietary patterns may interfere with the efficacy of herbal intervention. Our results demonstrated the protective effects of Salvia miltiorrhiza aqueous extract (SMA) on bone metabolism were influenced by levels of dietary fat and sucrose in ovariectomized (OVX) rats through its actions on attenuating lipid deposition and oxidative stress in rats. INTRODUCTION: Salvia miltiorrhiza (SM), also known as Danshen, has been tested as an osteoporosis treatment in a series of small, short human trials that generally report improvements in bone property. However, dietary patterns may interfere with the effects of herbal intervention. We hypothesized that dietary fat and sucrose levels could influence the effects of SM supplementation on bone in estrogen-deficient animals. METHODS: Six-month-old Sprague-Dawley sham or OVX rats were fed either a low-saturated fat-sucrose (LFS, a diet that was similar in composition to normal rat chow) or a high-fat-sucrose (HFS) diet and OVX rats were treated (8 rats/group) with SM aqueous extract (SMA, 600 mg/kg/day), 17ß-estradiol (1 mg/kg/day), or vehicle for 12 weeks. RESULTS: SMA significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats, but not in LFS-fed OVX rats. SMA greatly reduced lipid deposition and malondialdehyde levels, improved the activities of superoxide dismutase, catalase, and glutathione peroxidase in the livers of HFS-fed OVX rats. SMA could directly improve the proliferation and differentiation in vitro in an H2O2-induced preosteoblast cell model by attenuating cellular reactive oxygen species levels. CONCLUSIONS: The protective effects of SMA on bone metabolism were influenced by dietary fat and sucrose levels in OVX rats. The ability of SMA to reduce bone loss in HFS-fed OVX rats was associated with the attenuation of lipid deposition and oxidative stress levels.

Sensitive determinations of Cu, Pb, Cd, and Cr elements in aqueous solutions using chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy.

In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R2 of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 µg/mL for the unitary solution, and in the range of 0.025-0.420 µg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.

DAT isn't all that: cocaine reward and reinforcement require Toll-like receptor 4 signaling.

The initial reinforcing properties of drugs of abuse, such as cocaine, are largely attributed to their ability to activate the mesolimbic dopamine system. Resulting increases in extracellular dopamine in the nucleus accumbens (NAc) are traditionally thought to result from cocaine's ability to block dopamine transporters (DATs). Here we demonstrate that cocaine also interacts with the immunosurveillance receptor complex, Toll-like receptor 4 (TLR4), on microglial cells to initiate central innate immune signaling. Disruption of cocaine signaling at TLR4 suppresses cocaine-induced extracellular dopamine in the NAc, as well as cocaine conditioned place preference and cocaine self-administration. These results provide a novel understanding of the neurobiological mechanisms underlying cocaine reward/reinforcement that includes a critical role for central immune signaling, and offer a new target for medication development for cocaine abuse treatment.

Application of retrograde dissection method for isolation of bone marrow cells from rat femurs and tibiae.

Currently, there is no practical and efficient method for the isolation of bone marrow cells (BMCs) from rat femurs and tibiae. Here, we attempted to develop a rapid, simple, effective, and non-contaminating method for the isolation of BMCs from rat femurs and tibiae. Rat femurs and tibiae were dissected from the ankle to the hip joint; subsequently, a three-step "locate-slide-twist" procedure was performed using scissors and forceps to remove the femurs and tibiae completely, from the surrounding musculature. The bones were flushed with phosphate-buffered saline to harvest BMCs. The femurs and tibiae were dissected in 1.8 ± 0.6 min, and the BMC suspension preparation time was 13.1 ± 2.3 min. The bone marrow cavities did not incur any fractures or injuries during the isolation. Culture of harvested BMCs for 72 h led to a significant increase in cell number from 4.4 ± 0.3 x 106 to 6.9 ± 0.7 x 10(6) (P < 0.01) with no significant decrease in viability (98.1 ± 0.6% vs 96.2 ± 1.1%; P > 0.05). Microscopic examination of the isolated BMCs after the 72-h incubation period revealed the no-microbial or muscle cell contamination. Furthermore, flow cytometry revealed that cultured BMCs (72-h culture) grew well. Here, we have reported a rapid, simple, effective, and non-contaminating method for the isolation of BMCs from rat femurs and tibiae by using retrograde dissection. This method can be used to harvest a large number of viable BMCs without the risk of contamination from muscle and connective tissues.

Association between IL18-607C/A and -137G/C polymorphisms and susceptibility to non-small cell lung cancer in a Chinese population.

Lung cancer is one of the main causes of cancer-related mortality in males and females worldwide. A pleiotropic effect has been observed in the interleukin 18 gene (IL18); its effects include the activation of natural killer cell cytotoxicity and the promotion of the Th1 immune response through the alteration of the expression of interferon-γ and TNF-α in humans. IL18 is therefore involved in the elimination of tumor cells in the human body. We recruited 357 patients with non-small cell lung cancer (NSCLC) and 414 controls to evaluate the correlation between two genetic variations (IL18-607C/A and IL18-137G/C) and the pathogenesis of NSCLC. We used polymerase chain reaction-restriction fragment length polymorphism to genotype IL18-607C/A and IL18-137G/C. Statistical analysis revealed that individuals harboring the AA genotype of IL18-607C/A had an increased risk of NSCLC compared to those harboring the CC genotype (OR = 2.20, 95%CI = 1.30-3.74). Individuals expressing the A allele of IL18-607C/A had an elevated risk of developing NSCLC compared to those expressing the C allele (OR = 1.31, 95%CI = 1.06-1.62). In summary, our analysis shows that the IL18-607C/A genetic variation is related to the risk of NSCLC, whereas the IL18-137G/C variation is not. Therefore, the IL18-607C/A variation is related to the pathogenesis of NSCLC in the Chinese population studied.

Pattern of GHR mRNA expression and body growth in the S2 line of sex-linked dwarf chickens.

Sex-linked dwarf (SLD) chickens have been widely used in cross breeding of broilers and laying hens. To study the molecular mechanisms underlying growth hormone receptor (GHR) in SLD chickens, the expression profiles of GHR were measured in three growth related tissues (liver, breast, and thigh) in male and female S2 SLD chickens at seven growth stages (1 day, 3 weeks, 7 weeks, 9 weeks, 11 weeks, 13 weeks, and 15 weeks). Growth curves of body weight were fitted using logistic and Gompertz models. The results show that the inflexion week and inflexion weight in male chickens was earlier than in female chickens. Regarding the expression profiles of GHR, there was no significant difference between tissues at hatching. The expression peaked at 7 weeks and dropped by degrees in muscle tissue; hepatic expression increased with age and was positively correlated with body weight. Taken together, these results would provide a basis for further study on the molecular mechanisms underlying GHR regulation in SLD chickens.

[The effect of liraglutide in combination with human umbilical cord mesenchymal stem cells treatment on glucose metabolism and ß cell function in type 2 diabetes mellitus].

OBJECTIVE: To observe the effect of liraglutide (LIRA) in combination of umbilical cord mesenchymal stem cells (hUC-MSCs) in treating type 2 diabetes mellitus. METHODS: Eligibility criteria for subjects includes: type 2 diabetes mellitus with more than 10 years duration; having been treated with secretagogues, metformin and insulin in combination with LIRA for at least 6 months; poor glycemic control [glycosylated hemoglobin A1c(HbA1c) 7%-10%]. Totally, twelve patients were enrolled and randomly divided into two groups: the group A (LIRA group, n=6) and the group B (LIRA+ hUC-MSCs group, n=6). The hUC-MSCs were transplanted through infusing of 1×10(6) cells /kg via pancreatic artery directed by interventional radiology on the first day, and followed by infusing 1×10(6) cells /kg through peripheral vein on the eighth, the fifteenth and the twenty-second day sequentially. The control subjects were infused with saline. Both groups were treated with LIRA for 24 weeks at the same period. Fasting plasma glucose(FPG), 2h postprandial plasma glucose(2hPG) and HbA1c were measured. A 75 g oral glucose tolerance test(OGTT)was performed. The early phase of C peptide(CP) secretion function(ΔCP30/ΔG30), the total amount of C peptide secretion function(AUCCP180)and Homeostasis model assessment of insulin resistance (HOMA-IR) were calculated. RESULTS: (1) The baseline FPG, 2hPG, HbA1c, ΔCP30/ΔG30, AUCCP180 and HOMA-IR were comparable between the two groups(P>0.05). (2) Compared with subjects in group A, FPG, 2hPG and HbA1c levels were significantly decreased in subjects in group B [(8.33±0.99) mmol/L vs (6.64±0.79)mmol/L, (13.85±0.86) mmol/L vs (8.65±1.12) mmol/L, (7.82±0.31)% vs (6.82±0.53)%, P<0.05]. (3) Compared with group A, ΔCP30/ΔG30 and AUCCP180 were significantly increased, and HOMA-IR was significantly decreased in group B(0.22±0.13 vs 0.70±0.38, 12.52±5.30 vs 21.16±3.17, 9.46±4.88 vs 4.30±2.68, P<0.05). CONCLUSION: LIRA treatment in combination with hUC-MSCs improves glucose metabolism and the ß cell function in type 2 diabetic patients. (ClinicalTrials.gov NCT01954147).

[Preliminary application of amide proton transfer imaging signal in acute ischemic stroke].

OBJECTIVE: To apply amide proton transfer magnetic resonance imaging (APT-MRI) technique to acute ischemic stroke, and to discuss clinical values of the APT-MRI main parameter - MTRasym(3.5 ppm). METHODS: A total of 18 emergency admitted patients, with acute ischemic stroke from Beijing Hospital, were recruited from March to November 2015. Eventually, 18 patients (male 14, female 4, average age 72 years old, age ranged from 52 to 92 years, symptom onset ≤24 hours, 2 patients≤ 6 hours) were included in this study. All patients underwent MR scanning on the brain at 3.0 Tesla. Besides the conventional scans for stroke, the APT sequence (saturation time 0.8 s, saturation power 2 µT) was performed. APT weighted (APTW) images were calculated using magnetization transfer ratio asymmetry at 3.5 ppm with respect to water. MRI signals in APTW, diffusion weighted images (DWI) and fluid attenuated iversion recovery (FLAIR) were visually evaluated. Shapiro-Wilk tests were performed to find out the distribution of MTRasym(3.5 ppm) in the whole sample, infarction regions, and normal appearing white matter (NAWMs), respectively. Detrended normal P-P plots were also used to evaluate its normality. Paired-t test and two-sample t test were applied to compare the mean MTRasym(3.5 ppm) of infarction regions with that of contra lateral NAWMs. RESULTS: (1) High signal intensity was observed in DWI and FLAIR in all 18 patients. However, signal intensity was somewhat different in APTW. 13 patients were found decreased APT effect, and 5 patients were with equal APT effect in infarction regions. In NAWMs, 14 patients were found equal APT effect, and 4 patients were with decreased APT effect. (2) MTRasym(3.5 ppm)s were proven, with Shapiro-Wilk test, to distribute normally within the whole sample (W=0.964, P=0.288), infarction regions (W=0.962, P=0.645), and NAWMs(W=0.929, P=0.187). However, its normality was not so satisfactory due to greater deviations (absolute value>0.06) of some cases in detrended normal P-P plots. (3) Paired-t test analysis showed that MTRasym(3.5 ppm) in infarction regions (-0.035%±1.020%) was significantly lower than that in NAWMs (0.386%±0.790%) (t=-2.273, P=0.036). However, there was no statistically significant difference between infarction regions and NAWMs when two sample t-test was performed (t=-1.386, P=0.175). CONCLUSION: MTRasym(3.5 ppm) can be used to evaluate acute ischemic stroke with a broad future scope in clinical.

[The effect and injury to the airways of different sputum aspiration pressure in a rat model of mucus hypersecretion].

OBJECTIVE: To explore the optimal pressure of sputum aspiration to ensure the effectiveness and safety of clinical operation. METHODS: We established a rabbit model of airway mucus hypersecretion by aerosol acrolein inhalation, and the animals were divided into 4 groups randomly with different sputum aspiration pressure as follows: group A -75 mmHg (1 mmHg=0.133 kPa), group B -150 mmHg, group C -225 mmHg, group D -300 mmHg. Sputum aspiration efficiency and tracheal mucosal damage degree were evaluated by sputum volume, oxygen saturation changes, the pathological sections of tracheal mucosa and the expressions of IL-1ß and TNF-α in airway secretion. RESULTS: The sputum suction volume of group A, B, C, D were (2.72±0.24), (4.81±0.32), (5.03±0.37) and (6.29±0.51) ml, respectively, which was significantly higher in group D, but lower in group A, as compared to other groups (P<0.05). There were no significant differences between B and C groups. The maximal SpO2 decrease of C and D groups [(18.1±5.2)% and(32.4±8.4)%]were significantly higher than those in A and B groups [(4.4±1.7)% and (6.3±2.9)%], and group D was significantly more than group C, and the difference was statistically significant (P<0.05). There were no significant differences between A and B groups. HE staining of tracheal mucosa in C and D groups showed that the inflammatory cell infiltration and mucosal damage were more serious than A and B groups, but the airway mucosal damage of group A was the least. CONCLUSION: The pressure of -150 mmHg was more effective with high oxygen saturation and less airway injury, which may be suitable for clinical sputum aspiration.

[Research advances in drug-induced autoimmune hepatitis].

Drug induced autoimmune hepatitis (DIAIH) refers to the liver injury mediated by drug-induced autoimmune reaction. Since it has similar clinical features as idiopathic autoimmune hepatitis, it is often difficult to make differential diagnosis in clinical practice. A deep understanding of the development, pathogenesis, related drugs, risk factors, and clinical and histological features of DIAIH helps with the correct diagnosis and treatment of DIAIH.

Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression.

Laser-induced breakdown spectroscopy (LIBS) with partial least squares regression (PLSR) has been applied to measuring the acidity of iron ore, which can be defined by the concentrations of oxides: CaO, MgO, Al2O3, and SiO2. With the conventional internal standard calibration, it is difficult to establish the calibration curves of CaO, MgO, Al2O3, and SiO2 in iron ore due to the serious matrix effects. PLSR is effective to address this problem due to its excellent performance in compensating the matrix effects. In this work, fifty samples were used to construct the PLSR calibration models for the above-mentioned oxides. These calibration models were validated by the 10-fold cross-validation method with the minimum root-mean-square errors (RMSE). Another ten samples were used as a test set. The acidities were calculated according to the estimated concentrations of CaO, MgO, Al2O3, and SiO2 using the PLSR models. The average relative error (ARE) and RMSE of the acidity achieved 3.65% and 0.0048, respectively, for the test samples.

Upregulation of HO-1 with Haemin Alleviates LPS-Stimulated Pro-inflammatory Responses Through Downregulation of p38 Signalling Pathways in Rat Liver.

Haem oxygenase-1 (HO-1) plays an important role in inflammatory disease development and progression. Whether it has an anti-inflammatory role in lipopolysaccharide (LPS)-induced liver injury remains unclear. To investigate the functional role of HO-1 in protecting liver tissue against inflammatory response stimulated by LPS in rat and the mechanism by which it achieves this protective effect, LPS-stimulated inflammatory models were established. In pretreatment of rats with HO-1 activator (haemin) or inhibitor (zinc protoporphyrin-9, ZnPP, a specific inhibitor of HO) before LPS stimulation, we evaluated the pathological changes by haematoxylin-eosin staining. The mRNA expression and secretion of IL-1ß and IL-6 in rat liver were analysed using the real-time PCR and ELISA. Real-time PCR and Western blot were also used to evaluate the expression of HO-1, p38 and p-p38 in liver. Liver CO contents were sensitized to the expression of HO-1. Induction of HO-1 by haemin remarkably inhibited the expression of p38, and addition of ZnPP increased this expression. Our results demonstrate that HO-1 is an anti-inflammation factor in LPS-stimulated liver, which regulate the inflammatory response through downregulation of p38 signalling pathways in rat liver.

Dietary zinc may attenuate heat-induced testicular oxidative stress in mice via up-regulation of Cu-Zn SOD.

Zinc (Zn) is important for male mammalian reproduction. In this study, we sought to clarify the role of Zn in heat-induced testicular damage in mice. Eighteen mice were divided into either control (con), heat (heat) and heat plus Zn (H+Zn) treatment groups, and fed diets containing 60 (con and heat groups) or 300 (H+Zn group) mg/kg Zn sulfate for one month. Mice in the con group were then maintained at 25°C, while mice in heat and H+Zn groups were exposed to 40°C for 2 h daily, for eight days. Mouse testes and serum from each animal were analyzed. Zinc levels in serum and testes were positively correlated to Zn feed concentrations. Mice in the heat group had higher testes index than those in the other two groups (7.22 ± 0.75, heat; 4.92 ± 0.20, con; 4.80 ± 0.30 mg/g, H+Zn; P < 0.05). Testicular antioxidant status showed malondialdehyde levels in heat group mice were increased compared to control mice (2.34 ± 0.15 versus 1.55 ± 0.23 nmol/mg protein; P < 0.05), and Cu-Zn superoxide dismutase (SOD) level differed between heat and H+Zn groups (14.04 ± 0.74 versus 18.27 ± 1.53 U/mg protein; P < 0.05). Testicular Cu-Zn SOD protein expression levels were significantly lower in the heat than in the control group (0.30 ± 0.11 versus 1.22 ± 0.13; P < 0.05). These results suggest that dietary Zn may elevate the activity and protein concentration of Cu-Zn SOD, to attenuate testicular oxidative stress induced by heat exposure.

Genetic polymorphisms of the BMAP-28 and MASP-2 genes and their correlation with the somatic cell score in Chinese Holstein cattle.

DNA sequencing, nested polymerase chain reaction (PCR), and PCR-restriction fragment length polymorphism were used to investigate mutations in the coding regions of the bovine myeloid antimicrobial peptide-28 (BMAP-28) and mannan-binding lectin-associated serine protease-2 (MASP-2) genes in 249 Chinese Holstein dairy cows. The associations between the polymorphisms and somatic cell score (SCS) were analyzed to determine the potential of these genes as genetic markers for breeding mastitis-resistant dairy cattle. The results revealed a C-86G synonymous mutation in the BMAP-28 gene that caused no alteration in the amino acid sequence. G553A mutation was found in the MASP-2 gene that led to the substitution of glycine with serine. The chi-square test showed that the G553A mutation was in Hardy-Weinberg equilibrium in the Chinese Holstein dairy cows, whereas the C-86G mutation was not. The variance analysis of the influence of group loci and different genotypes on the SCS showed that the SCS of genotype CC was significantly lower than those of genotypes CG and GG (P < 0.05) of the C-86G mutation, and that the SCS of genotype GG was significantly lower than those of genotypes GA and AA (P < 0.05) of the G553A mutation. Genotype combination analysis showed that the combination of the BMAP-28 genotype CC and the MASP-2 genotype GG was the best one, in which the SCS was significantly lower than those in the other combinations. Thus, this combination might be useful as a molecular and genetic marker of mastitis in Chinese Holstein dairy cows.

Polymorphism identification in BMP15 and GDF9 genes and their association with egg production in chickens.

1. Mutations in growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are significantly associated with reproductive performance in mammals and the objective of the present study was to identify polymorphic sites and elucidate the association between genotypes in BMP15 and GDF9 and egg production. 2. Polymorphisms in BMP15 exon1 and GDF9 exon2 were detected by DNA sequencing and PCR-RFLP. Three SNPs were detected in each of BMP15 (A111G, C231T and C34T) and GDF9 (G593A, T824C and C896T). C34T leads to the substitution of Leu by Phe, which was predicted to affect protein function. 3. Results of the association analysis indicated that C34T had an effect on total egg production at 300 d of age (EN) and age at first laying (AFE). G593A affected EN and both C231T and C896T influenced AFE. The TGC1TGC1 diplotype in BMP15 had the highest EN. 4. In conclusion, EN may be significantly improved by marker-assisted selection of the BMP15 genotypes in maternal lines of Shaobo hens.