Fertility on synchronized estrus in crossbred (Bos taurus x Bos indicus) heifers

This study was performed in Western Maharastra (India). The 272 crossbred heifers were randomly allocated within herds to one of the four following groups: 1) silastic coils, 10 days treatment (n = 65); 2) Norgestomet implants, 10 days treatment (n = 71); 3) prostaglandin F(2alpha) two injections 11 days apart (n = 70); and 4) control (n = 66). Almost all heifers in the treated groups were detected in heat during the four days following treatment (88-100%) vs 26% in the control group in the first 21 days. Mean conception rates at first AIs were respectively 62,48 and 60% in groups 1,2 and 4 (p > 0.05) and only 29% in group 3. By 90 days after treatment, 66, 59, 46 and 33 per cent of the females were pregnant for groups 1 to 4, respectively (p < 0.001). In conclusion, progestogen treatments seemed to be highly satisfactory both in terms of conception rates and intervals from treatment to pregnancy.     

Segregation characteristics of multiple chromosomes ofAzotobacter vinelandii

The genome ofAzotobacler vinelandii has been taggedin vivo with transposons. The cells have then been allowed to divide and the pattern of segregation of the genomes has been studied. The results suggest the presence of multiple (possibly identical) copies of the genome inA. vinelandii. Only a fraction of the total number of genomes seem to have been tagged with transposon and an equilibrium between alleles of the same gene with and without the transposon was evident during random segregation.     

Identification of a Novel Penicillin-Binding Protein from Helicobacter pylori

The Helicobacter pylori genome encodes four penicillin-binding proteins (PBPs). PBPs 1, 2, and 3 exhibit similarities to known PBPs. The sequence of PBP 4 is unique in that it displays a novel combination of two highly conserved PBP motifs and an absence of a third motif. Expression of PBP 4, but not PBP 1, 2, or 3, is significantly increased during mid- to late-log-phase growth.     

Identifying Environmental Determinants of Diurnal Distribution in Marine Birds and Mammals

Marine birds and mammals move between various habitats during the day as they engage in behaviors related to resting, sleeping, preening, feeding, and breeding. The per capita rates of movement between these habitats, and hence the habitat occupancy dynamics, often are functions of environmental variables such as tide height, solar elevation, wind speed, and temperature. If the system recovers rapidly after disturbance, differential equation models of occupancy dynamics can be reduced to algebraic equations on two time scales. Identification of environmental factors that influence movement between habitats requires time series census data collected in both the absence and presence of disturbance.     

Microbial diversity in saliva of oral squamous cell carcinoma

In the oral cavity, chronic inflammation has been observed at various stages of oral squamous cell carcinomas (OSCC). Such inflammation could result from persistent mucosal or epithelial cell colonization by microorganisms. There is increasing evidence of the involvement of oral bacteria in inflammation, warranting further studies on the association of bacteria with the progression of OSCC. The objective of this study was to evaluate the diversity and relative abundance of bacteria in the saliva of subjects with OSCC. Using 454 parallel DNA sequencing, ～58,000 PCR amplicons that span the V4-V5 hypervariable region of rRNAs from five subjects were sequenced. Members of eight phyla (divisions) of bacteria were detected. The majority of classified sequences belonged to the phyla Firmicutes (45%) and Bacteroidetes (25%). Further, 52 different genera containing approximately 860 (16.51%) known species were identified and 1077 (67%) sequences belonging to various uncultured bacteria or unclassified groups. The species diversity estimates obtained with abundance-based coverage estimators and Chao1 were greater than published analyses of other microbial profiles from the oral cavity. Fifteen unique phylotypes were present in all three OSCC subjects.     

Sister chromatids fail to separate during an induced endoreplication cycle in Drosophila embryos

When mitosis is bypassed, as in some cancer cells or in natural endocycles, sister chromosomes remain paired and produce four-stranded diplochromosomes or polytene chromosomes. Cyclin/Cdk1 inactivation blocks entry into mitosis and can reset G2 cells to G1, allowing another round of replication. Reciprocally, persistent expression of Cyclin A/Cdk1 or Cyclin E/Cdk2 blocks Drosophila endocycles. Inactivation of Cyclin A/Cdk1 by mutation or overexpression of the Cyclin/Cdk1 inhibitor, Roughex (Rux), converts the 16(th) embryonic mitotic cycle to an endocycle; however, we show that Rux expression fails to convert earlier cell cycles unless Cyclin E is also downregulated. Following induction of a Rux transgene in Cyclin E mutant embryos during G2 of cell cycle 14 (G2(14)), Cyclins A, B, and B3 disappeared and cells reentered S phase. This rereplication produced diplochromosomes that segregated abnormally at a subsequent mitosis. Thus, like the yeast CKIs Rum1 and Sic1, Drosophila Rux can reset G2 cells to G1. The observed cyclin destruction suggests that cell cycle resetting by Rux was associated with activation of the anaphase-promoting complex (APC), while the presence of diplochromosomes implies that this activation of APC outside of mitosis was not sufficient to trigger sister disjunction.     

Birth, death, and replacement of karyopherins in Drosophila

Nucleocytoplasmic transport is a broadly conserved process across eukaryotes. Despite its essential function and conserved mechanism, components of the nuclear transport apparatus have been implicated in genetic conflicts in Drosophila, especially in the male germ line. The best understood case is represented by a truncated RanGAP gene duplication that is part of the segregation distorter system in Drosophila melanogaster. Consistent with the hypothesis that the nuclear transport pathway is at the heart of mediating genetic conflicts, both nucleoporins and directionality imposing components of nuclear transport have previously been shown to evolve under positive selection. Here, we present a comprehensive phylogenomic analysis of importins (karyopherins) in Drosophila evolution. Importins are adaptor molecules that physically mediate the transport of cargo molecules and comprise the third component of the nuclear transport apparatus. We find that importins have been repeatedly gained and lost throughout various stages of Drosophila evolution, including two intriguing examples of an apparently coincident loss and gain of nonorthologous and noncanonical importin-α. Although there are a few signatures of episodic positive selection, genetic innovation in importin evolution is more evident in patterns of recurrent gene birth and loss specifically for function in Drosophila testes, which is consistent with their role in supporting host genomes defense against segregation distortion.     

Comparison of oral microbiota in tumor and non-tumor tissues of patients with oral squamous cell carcinoma

ABSTRACT: BACKGROUND: Bacterial infections have been linked to malignancies due to their ability to induce chronicinflammation. We investigated the association of oral bacteria in oral squamous cellcarcinoma (OSCC/tumor) tissues and compared with adjacent non-tumor mucosa sampled 5cm distant from the same patient (n = 10). By using culture-independent 16S rRNAapproaches, denaturing gradient gel electrophoresis (DGGE) and cloning and sequencing, weassessed the total bacterial diversity in these clinical samples. RESULTS: DGGE fingerprints showed variations in the band intensity profiles within non-tumor andtumor tissues of the same patient and among the two groups. The clonal analysis indicatedthat from a total of 1200 sequences characterized, 80 bacterial species/phylotypes weredetected representing six phyla, Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria,Actinobacteria and uncultivated TM7 in non-tumor and tumor libraries. In combined library,12 classes, 16 order, 26 families and 40 genera were observed. Bacterial species,Streptococcus sp. oral taxon 058, Peptostreptococcus stomatis, Streptococcus salivarius,Streptococcus gordonii, Gemella haemolysans, Gemella morbillorum, Johnsonella ignavaand Streptococcus parasanguinis I were highly associated with tumor site where asGranulicatella adiacens was prevalent at non-tumor site. Streptococcus intermedius waspresent in 70% of both non-tumor and tumor sites. CONCLUSIONS: The underlying changes in the bacterial diversity in the oral mucosal tissues from non-tumorand tumor sites of OSCC subjects indicated a shift in bacterial colonization. These mostprevalent or unique bacterial species/phylotypes present in tumor tissues may be associatedwith OSCC and needs to be further investigated with a larger sample size.