Observations on bacteria associated with pigeon crop

Lactobacilli, streptococci and coliforms of pigeon crop contents, 5th wash, macerate and those of first-day pigeon milk have been studied. Streptococci predominated in all the samples tested. Relatively higher counts of lactobacilli and streptococci in crop macerate than in the 5th wash suggested the adhesion of these bacteria to crop wall. Because of frequent occurrence in crop of partially digested fibrous food, its contents were tested for the presence of cellulolytic bacteria. The results indicated that four isolates were capable of utilizing cellulose with the resultant production of reducing sugars. It is inferred that the crop microflora is involved in the degradation of dietary fibre in the pigeon.     

Using comparative genomics to reorder the human genome sequence into a virtual sheep genome

Background

Is it possible to construct an accurate and detailed subgene-level map of a genome using bacterial artificial chromosome (BAC) end sequences, a sparse marker map, and the sequences of other genomes?

Results

A sheep BAC library, CHORI-243, was constructed and the BAC end sequences were determined and mapped with high sensitivity and low specificity onto the frameworks of the human, dog, and cow genomes. To maximize genome coverage, the coordinates of all BAC end sequence hits to the cow and dog genomes were also converted to the equivalent human genome coordinates. The 84,624 sheep BACs (about 5.4-fold genome coverage) with paired ends in the correct orientation (tail-to-tail) and spacing, combined with information from sheep BAC comparative genome contigs (CGCs) built separately on the dog and cow genomes, were used to construct 1,172 sheep BAC-CGCs, covering 91.2% of the human genome. Clustered non-tail-to-tail and outsize BACs located close to the ends of many BAC-CGCs linked BAC-CGCs covering about 70% of the genome to at least one other BAC-CGC on the same chromosome. Using the BAC-CGCs, the intrachromosomal and interchromosomal BAC-CGC linkage information, human/cow and vertebrate synteny, and the sheep marker map, a virtual sheep genome was constructed. To identify BACs potentially located in gaps between BAC-CGCs, an additional set of 55,668 sheep BACs were positioned on the sheep genome with lower confidence. A coordinate conversion process allowed us to transfer human genes and other genome features to the virtual sheep genome to display on a sheep genome browser.

Conclusion

We demonstrate that limited sequencing of BACs combined with positioning on a well assembled genome and integrating locations from other less well assembled genomes can yield extensive, detailed subgene-level maps of mammalian genomes, for which genomic resources are currently limited.     

Mesenchymal stem cell-based HSP70 promoter-driven VEGFA induction by resveratrol promotes angiogenesis in a mouse model

Several studies of stem cell-based gene therapy have indicated that long-lasting regeneration following vessel ischemia may be stimulated through VEGFA gene therapy and/or MSC transplantation for reduction of ischemic injury in limb ischemia and heart failure. The therapeutic potential of MSC transplantation can be further improved by genetically modifying MSCs with genes which enhance angiogenesis following ischemic injury. In the present study, we aimed to develop an approach in MSC-based therapy for repair and mitigation of ischemic injury and regeneration of damaged tissues in ischemic disease. HSP70 promoter-driven VEGFA expression was induced by resveratrol (RSV) in MSCs, and in combination with known RSV biological functions, the protective effects of our approach were investigated by using ex vivo aortic ring coculture system and a 3D scaffolds in vivo model. Results of this investigation demonstrated that HSP promoter-driven VEGFA expression in MSC increased approximately 2-fold over the background VEGFA levels upon HSP70 promoter induction by RSV. Exposure of HUVEC cells to medium containing MSC in which VEGFA had been induced by cis-RSV enhanced tube formation in the treated HUVEC cells. RSV-treated MSC cells differentiated into endothelial-like phenotypes, exhibiting markedly elevated expression of endothelial cell markers. These MSCs also induced aortic ring sprouting, characteristic of neovascular formation from pre-existing vessels, and additionally promoted neovascularization at the MSC transplantation site in a mouse model. These observations support a hypothesis that VEGFA expression induced by cis-RSV acting on the HSP70 promoter in transplanted MSC augments the angiogenic effects of stem cell gene therapy. The use of an inducible system also vastly reduces possible clinical risks associated with constitutive VEGFA expression.     

Oral malignant melanoma--an unusual presentation

Malignant melanoma is the least common but most deadly of all primary skin cancers. Oral malignant melanoma is a rare aggressive neoplasm usually seen in middle aged persons. This malignancy is more frequently seen on the hard palate and gingiva. Oral melanomas are associated with very poor prognosis because of the tendency to metastasise or invade tissues locally more readily than other malignant tumours of the oral cavity especially in the case of a geriatric patient. The surgical approach, combined with the chemotherapy, is the first choice treatment. This report highlights a case report of 71-year-old female patient diagnosed and treated surgically for an oral malignant melanoma of the pedunculated variety affecting the hard palate and gingiva with review of literature.     

Vimentin expressed on Mycobacterium tuberculosis-infected human monocytes is involved in binding to the NKp46 receptor

We previously showed that human NK cells used the NKp46 receptor to lyse Mycobacterium tuberculosis H37Ra-infected monocytes. To identify ligands on H37Ra-infected human mononuclear phagocytes, we used anti-NKp46 to immunoprecipitate NKp46 from NK cells bound to its ligand(s) on H37Ra-infected monocytes. Mass spectrometry analysis identified a 57-kDa molecule, vimentin, as a putative ligand for NKp46. Vimentin expression was significantly up-regulated on the surface of infected monocytes, compared with uninfected cells, and this was confirmed by fluorescence microscopy. Anti-vimentin antiserum inhibited NK cell lysis of infected monocytes, whereas antiserum to actin, another filamentous protein, did not. CHO-K1 cells transfected with a vimentin construct were lysed much more efficiently by NK cells than cells transfected with a control plasmid. This lysis was inhibited by mAb-mediated masking of NKp46 (on NK cells) or vimentin (on infected monocytes). ELISA and Far Western blotting showed that recombinant vimentin bound to a NKp46 fusion protein. These results indicate that vimentin is involved in binding of NKp46 to M. tuberculosis H37Ra-infected mononuclear phagocytes.     

Potential of Ginkgo biloba L. leaves in the management of hyperglycemia and hypertension using in vitro models

Leaves from four different Ginkgo biloba L. trees (1 and 2 – females; 3 and 4 – males), grown at the same conditions, were collected during a period of 5 months (from June to October, 2007). Water and 12% ethanol extracts were analyzed for total phenolics content, antioxidant activity, phenolic profile, and the potential in vitro inhibitory effects on α-amylase, α-glucosidase, and Angiotensin I-Converting Enzyme (ACE) enzymes related to the management of diabetes and hypertension. The results indicated a significant difference among the trees in all functional benefits evaluated in the leaf extracts and also found important seasonal variation related to the same functional parameters. In general, the aqueous extracts had higher total phenolic content than the ethanolic extracts. Also, no correlation was found between total phenolics and antioxidant activity. In relation to the ACE inhibition, only ethanolic extracts had inhibitory activity.     

A homozygous mutation in LTBP2 causes isolated microspherophakia

Microspherophakia is an autosomal-recessive congenital disorder characterized by small spherical lens. It may be isolated or occur as part of a hereditary systemic disorder, such as Marfan syndrome, autosomal dominant and recessive forms of Weill-Marchesani syndrome, autosomal dominant glaucoma–lens ectopia–microspherophakia–stiffness–shortness syndrome, autosomal dominant microspherophakia with hernia, and microspherophakia-metaphyseal dysplasia. The purpose of this study was to map and identify the gene for isolated microspherophakia in two consanguineous Indian families. Using a whole-genome linkage scan in one family, we identified a likely locus for microspherophakia (MSP1) on chromosome 14q24.1–q32.12 between markers D14S588 and D14S1050 in a physical distance of 22.76 Mb. The maximum multi-point lod score was 2.91 between markers D14S1020 and D14S606. The MSP1 candidate region harbors 110 reference genes. DNA sequence analysis of one of the genes, LTBP2, detected a homozygous duplication (insertion) mutation, c.5446dupC, in the last exon (exon 36) in affected family members. This homozygous mutation is predicted to elongate the LTBP2 protein by replacing the last 6 amino acids with 27 novel amino acids. Microspherophakia in the second family did not map to this locus, suggesting genetic heterogeneity. The present study suggests a role for LTBP2 in the structural stability of ciliary zonules, and growth and development of lens.