S-novel SNP of alpha-lactalbumin gene in chinese dairy goats

The alpha-lactalbumin (alpha-LA) plays a key role in lactose synthesis in mammary glands of domestic animals. Mutations in the alpha-LA gene are associated with the milk traits in dairy cattle. In our study, a novel SNP: NO_X06366:g.875 C > T was detected in 708 dairy goat individuals--268 of the Xinong Saanen breed and 440 of Guanzhong breed, which revealed a synonymous mutation in the exon 1 of alpha-LA gene. The Polymerase Chain Reaction-Single Strand Conformation Polymorphism (PCR-SSCP) and sequencing techniques showed that there were three genotypes: CC, CT and TT. Moreover, the chi2-test showed that the genotype frequencies of the two breeds were in good agreement with the Hardy-Weinberg equilibrium (P > 0.05). The relationship of the polymorphism of dairy goat alpha-LA gene with the milk trait and the body size trait was revealed. Individuals with the CC genotype were significantly smaller at chest circumference than those with CT (P < 0.05) in both breeds. But the milk trait and other body size traits of the two dairy goat breeds had no significant association with genotypes studied.

Establishment of an H6N2 influenza virus lineage in domestic ducks in southern China

Multiple reassortment events between different subtypes of endemic avian influenza viruses have increased the genomic diversity of influenza viruses circulating in poultry in southern China. Gene exchange from the natural gene pool to poultry has contributed to this increase in genetic diversity. However, the role of domestic ducks as an interface between the natural gene pool and terrestrial poultry in the influenza virus ecosystem has not been fully characterized. Here we phylogenetically and antigenically analyzed 170 H6 viruses isolated from domestic ducks from 2000 to 2005 in southern China, which contains the largest population of domestic ducks in the world. Three distinct hemagglutinin lineages were identified. Group I contained the majority of isolates with a single internal gene complex and was endemic in domestic ducks in Guangdong from the late 1990s onward. Group II was derived from reassortment events in which the surface genes of group I viruses were replaced with novel H6 and N2 genes. Group III represented H6 viruses that undergo frequent reassortment with multiple virus subtypes from the natural gene pool. Surprisingly, H6 viruses endemic in domestic ducks and terrestrial poultry seldom reassort, but gene exchanges between viruses from domestic ducks and migratory ducks occurred throughout the surveillance period. These findings suggest that domestic ducks in southern China mediate the interaction of viruses between different gene pools and facilitate the generation of novel influenza virus variants circulating in poultry.

Construction of an Acid-Tolerant Rhizobium leguminosarum Biovar Trifolii Strain with Enhanced Capacity for Nitrogen Fixation

Strain ANU1173 is an acid-tolerant Rhizobium leguminosarum biovar trifolii strain that is able to nodulate subterranean clover plants growing in agar culture at pH 4.4 At pH 6.5, its symbiotic effectiveness in association with Trifolium subterraneum cv. Mt. Barker was 80% relative to that of strain ANU794, a Sm derivative of the commercial inoculant R. leguminosarum bv. trifolii TA1. Strain ANU1173 contained four indigenous megaplasmids, the smallest of these being the symbiotic (Sym) plasmid. The critical pH requirement for growth of strain ANU1173 in laboratory media was shown not to be associated with this plasmid. When the Sym plasmid of strain ANU1173(pSym-1173) was mobilized into a Nod strain of R. leguminosarum bv. viciae, the plasmid conferred to the transconjugant a level of symbiotic effectiveness in association with T. subterraneum that was similar to that observed with ANU1173. The symbiotic effectiveness of strain ANU1173 was improved by first curing pSym-1173 (generating strain ANU1184) and replacing it with another R. leguminosarum bv. trifolii Sym plasmid, pBR1AN. Subterranean clover plants inoculated with strain ANU1184 (pBR1AN) exhibited a 35 or 53% increase in acetylene reduction activity and a 20 or 17% increase in dry weight when grown at pH 6.5 and pH 4.4, respectively, compared with plants inoculated with strain ANU1173 and grown under the same pH conditions. It was further shown that pBR1AN was stably maintained in strain ANU1184 under free-living and symbiotic conditions. These results indicate that it is possible to construct an acid-tolerant strain of R. leguminosarum bv. trifolii with an enhanced capacity for nitrogen fixation.

Evidence for competing magnetic and superconducting phases in superconducting Eu 1-x Sr x Fe 2-y Co y As 2 single crystals

In single crystals of Eu(1-x)Sr(x)Fe(2-y)Co(y)As(2), Co doping suppresses spin-density wave (SDW) ordering and induces a superconducting transition. A resistivity reentrance due to the antiferromagnetic ordering of Eu(2+) spins is observed, indicating the competition between antiferromagnetism (AFM) and superconductivity (SC). It is striking that the resistivity reentrance can be completely suppressed by a small magnetic field due to a field-induced metamagnetic transition from AFM to ferromagnetism (FM). The resistivity reentrance can also be suppressed by the substitution of Eu(2+) ions with nonmagnetic Ba(2+)/Sr(2+) to completely destroy the AFM ordering. These results indicate that the AFM order appears destructive to SC, while FM can coexist with the superconductivity. Further we find that magnon excitation exists in AFM ordering and can be suppressed by an applied field. Coexistence of SC from the FeAs layer and the inner field produced by the ferromagnetic Eu(2+) layer suggest a possible p-wave component in the superconducting order parameter.

The platinum-based treatments for advanced non-small cell lung cancer, is low/negative ERCC1 expression better than high/positive ERCC1 expression? A meta-analysis

BACKGROUND

The predictive value of ERCC1 for prognosis and sensitivity to platinum-based chemotherapy in patients with non-small cell lung cancer (NSCLC) remains controversial. This meta-analysis was performed to provide an assessment of whether expression variations of ERCC1 are associated with objective response and median survival in patients with advanced NSCLC treated with platinum-based chemotherapy.

METHODS

We searched MEDLINE, EMBASE and CNKI for all eligible studies and conducted a meta-analysis of 12 studies (n=836 patients) that evaluated the correlation between ERCC1 levels (detected by immunohistochemistry or real-time reverse transcriptase PCR) and objective response or median survival in patients receiving platinum-based chemotherapy for advanced NSCLC. Pooled odds ratios (OR) for the objective response were calculated using the Mantel-Haenszel method. Pooled median ratios for median survival were calculated using the weighted sum of the log-ratio of median ratios from each individual study.

RESULTS

Among 836 tumors, ERCC1 expression was high/positive in 416 (49.8%) and low/negative in 420 (50.2%). Response to platinum-based chemotherapy was significantly higher in patients with ERCC1 low/negative expression (OR=0.48; 95% CI, 0.35-0.64; P<0.00001). Median survival time was significantly prolonged when ERCC1 low/negative expression was compared with ERCC1 high/positive expression (MR: 0.77; 95% CI, 0.47-1.07; P<0.00001).

CONCLUSIONS

Low/negative expression of ERCC1 was associated with higher objective response and median survival in advanced NSCLC patients treated with platinum-based chemotherapy. ERCC1 may be a suitable marker of prognosis and sensitivity to platinum-based chemotherapy in patients with advanced NSCLC.

Effect of intermittent treatment with human Parathyroid Hormone 1-34 in SAMP6 senescence-accelerated mice

We examined trabecular and cortical bone in the senescence-accelerated mouse prone 6 (SAMP6) murine model of senile osteoporosis after treatment with human PTH 1-34. Sixteen-week-old female SAMP6 mice were assigned to control and PTH groups. PTH (20 microg/kg) was administered sc 3 times a week for 12 weeks. The control mouse strain, senescence-accelerated mouse resistant 1 (SAMR1), was used for comparison. The femoral metaphysis and diaphysis were used to measure bone mineral density (BMD), analyze the trabecular and the cortical structure by micro-computed tomography, and for conducting the bone strength test. PTH significantly attenuated the loss of BMD, improved the trabecular bone microstructure, and increased the bone strength in the femoral metaphysis. We did not find any differences in the bone strength of the femoral diaphysis after PTH treatment, although the cortical bone volume and cortical thickness were improved. Although the cortical thickness increased, the cortical bone density decreased, likely because of the increase of cortical porosity in the distal metaphysis after administration of PTH.

Effects of alendronate and strontium ranelate on cancellous and cortical bone mass in glucocorticoid-treated adult rats

We studied the effects of alendronate (Aln) and strontium ranelate (SrR) administration on cancellous and cortical bone in glucocorticoid (GC)-treated rats. Thirty-two 3.5-month male Sprague-Dawley rats were randomized into four groups: age-matched normal control (Nrm), methylprednisolone (Met; 5.0 mg/kg/day, sc, for 5 days/week), Met plus Aln orally (1.0 mg/kg/day), and Met plus SrR orally (900 mg/kg/day). The study period was 9 weeks. DXA was used to evaluate the femoral diaphysis and fifth lumbar vertebra (L5). Histomorphometry was performed in the proximal tibial metaphysis and tibial diaphysis. Met significantly decreased body weight and bone mineral density (BMD) compared with Nrm. Aln and SrR significantly increased body weight and BMD compared with Met. SrR resulted in significantly higher BMD than Aln. Met markedly decreased BV/TV, Tb.Th, and Tb.N and increased Tb.Sp compared with Nrm. Aln and SrR showed significantly increased of BV/TV, Tb.Th, and Tb.N and improved bone architecture. Moreover, Met reduced %Ct.Ar, enlarged %Ma.Ar, and decreased bone formation indices in the periosteum as well as increased ES/BS in the endosteum compared with Nrm. Aln significantly decreased endosteal ES/BS compared with Met. SrR significantly increased %Ct.Ar and bone formation indices in the periosteum as well as the endosteum and decreased endosteal ES/BS compared with Met. Furthermore, SrR led to a significantly higher cancellous and endocortical MS/BS and endocortical bone formation compared with Aln. Our findings suggest SrR at a dose of 900 mg/kg has a greater effect than Aln at 1.0 mg/kg, according to BMD and histomorphometric analysis, in preventing GC-induced osteopenia. Therefore, SrR might be applicable as a bone therapeutic agent to treat secondary osteoporosis in the clinic.

1H-MRS at 4 tesla in minimally treated early schizophrenia

We investigated glutamate-related neuronal dysfunction in the anterior cingulate (AC) early in schizophrenia before and after antipsychotic treatment. A total of 14 minimally treated schizophrenia patients and 10 healthy subjects were studied with single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) of the AC, frontal white matter and thalamus at 4 T. Concentrations of N-acetylaspartate (NAA), glutamate (Glu), glutamine (Gln) and Gln/Glu ratios were determined and corrected for the partial tissue volume. Patients were treated with antipsychotic medication following a specific algorithm and (1)H-MRS was repeated after 1, 6 and 12 months. There were group x region interactions for baseline NAA (P=0.074) and Gln/Glu (P=0.028): schizophrenia subjects had lower NAA (P=0.045) and higher Gln/Glu (P=0.006) in the AC before treatment. In addition, AC Gln/Glu was inversely related to AC NAA in the schizophrenia (P=0.0009) but not in the control group (P=0.92). Following antipsychotic treatment, there were no further changes in NAA, Gln/Glu or any of the other metabolites in any of the regions studied. We conclude that early in the illness, schizophrenia patients already show abnormalities in glutamatergic metabolism and reductions in NAA consistent with glutamate-related excitotoxicity.

Genetic variation of the peroxisome proliferator-activated receptor alpha gene (PPARA) in chickens bred for different purposes

Peroxisome proliferator-activated receptor alpha (PPARA) is involved in fatty acid oxidation by upregulating the expression of acyl-coenzyme A oxidase and carnitine palmitoyltransferase. In this study, PPARA gene variations in four chicken breeds (Guyuan, Wenchang, Tibetan, and Hisex) were detected by PCR-SSCP and DNA sequencing. The results indicated six genotypes (AA-EF). When compared with the PPARA reference sequence (GenBank accession no. AF163809), the nucleotide sequences of genotypes AA, BB, AB, and CC revealed silent mutations in the three Chinese breeds. The nucleotide sequences of genotypes DD and EF in Hisex showed several frame-shift mutations, implying variations involving five alleles of the PPARA gene in chicken breeds. In addition, the distribution of genotype frequency within the PPARA gene was significantly different in the four breeds studied, implying that this locus would probably be an effective marker in marker-assisted selection for layer, meat-and-egg, and broiler breeds.

A novel single-nucleotide polymorphism of the visfatin gene and its associations with performance traits in the chicken

Visfatin is a peptide that is predominantly expressed in visceral adipose tissue and is hypothesized to be related to obesity and insulin resistance. In this study, a novel silent single-nucleotide polymorphism (SNP) was found in exon 7 of the chicken visfatin gene (also known as PBEF1) by single-stranded conformation polymorphism (SSCP) and DNA sequencing. In total, 836 chickens forming an F2 resource population of Gushi chicken crossed with Anka broiler were genotyped by XbaI forced RFLP, and the associations of this polymorphism with chicken growth, carcass characteristics, and meat quality were analyzed. Significant associations were found between the polymorphism and 4-week body weight (BW4), 6-week body weight (BW6), 4-week body slanting length (BSL4), fat bandwidth (FBW), breast muscle water loss rate (BWLR) and breast muscle fiber density (BFD) (P < 0.05), as well as 4-week breastbone length (BBL4) (P < 0.01). These observations suggested that the polymorphism in exon7 of the visfatin gene had significant effects on the early growth traits of chicken.