Understanding Darjeeling tea flavour on a molecular basis.

Darjeeling teas are the highest grown teas in the world and preferred for its flavour, aroma and quality. Apart from the genetic makeup of the plant, earlier reports suggest that insect infestation, particularly jassids and thrips triggers the aroma and flavour formation in Darjeeling tea. The present work encompasses the identification of the genes/transcriptomes responsible for the typical flavour of Darjeeling tea, besides understanding the role of jassids and thrips in particular, in producing the best cup character and quality. The quantitative real time PCR analysis was based on a suppression subtractive hybridisation forward library of B157 (tea clone infested with thrips), providing us transcripts related to aroma and flavour formation. We observed the expression of genes like leucine zipper, ntd, nced, geraniol synthase, raffinose synthase, trehalose synthase, amylase, farnesyl transferase, catalase, methyl transferase, linalool synthase, peroxidases, elicitor responsive proteins, linamarase, nerolidol linalool synthase 2, 12-oxophytodienoate reductase, glucosidase, MYB transcription factor, and alcohol dehydrogenase, highly regulated due to insect infestation, manufacturing stresses and mechanical injury. The first report on gene expression dynamics in thrips infested Darjeeling tea leaves can be extrapolated with increase in volatiles which is responsible for enhancing the quality of Darjeeling tea, specially the flavour and aroma of the infusion. We hope to model these responses in order to understand the molecular changes that occur during Darjeeling tea flavour formation.

Uso de Styphnodendron poliphyllum (Barbatimão) a 5% em gel de hidroxietilcelulose em feridas cutâneas de camundongos

O artigo não apresenta resumo.

Molting hormonal and larvicidal activities of aliphatic acyl analogs of dibenzoylhydrazine insecticides.

Dibenzoylhydrazines are the nonsteroidal ecdysone agonists. Using comparative molecular field analysis, we previously found that the alkyl side chain of 20-hydroxyecdysone (20E) is three-dimensionally superposable with one of their two aryl moieties. To identify the aryl moiety that is better superposable on the alkyl chain, we synthesized compounds in which one of the two aryl groups of tebufenozide (N-t-butyl-N-3,5-dimethylbenzoyl-N'-4-ethylbenzoylhydrazine) is replaced by alkyl groups such as C4H9, C5H11, and C6H13. The molting hormonal activity of these compounds was measured using cultured integuments prepared from rice stem borers, Chilo suppressalis Walker, in terms of stimulation of incorporation of N-acetyl-[14C]glucosamine. N-t-Butyl-N-3,5-dimethylbenzoyl-N'-acylhydrazines with a hexanoyl or heptanoyl group were about 20-fold higher than that of 20E, whereas N-acyl-N-t-butyl-N'-4-ethylbenzoylhydrazines with a hexanoyl or heptanoyl group were much weaker than 20E. Their larvicidal activity was also measured against rice stem borers. The former series of compounds were much more active than the other series as well as 20E. Thus, the benzoyl moiety of dibenzoylhydrazines, which is bound to the secondary nitrogen atom (-NH-), is replaceable by aliphatic acyl groups without greatly affecting the biological activities.

A single-base mutation in exon 31 converting glycine 852 to arginine in the collagenous domain in an Alport syndrome patient.

In a family with Alport syndrome, molecular analysis of the COL4A5 gene, which encodes the alpha 5(IV) chain of glomerular basement membrane collagen, revealed a GGA-->AGA change in exon 31, resulting in substitution of an arginine for a glycine in position 852 of the polypeptide chain, between interruptions 16 and 17 of the triple-helical collagenous domain. The mutation causes the MaeI restriction sites, and could be easily diagnosed in the family members through restriction analysis. This one point mutation can be expected to interrupt type IV collagen molecules.

Typing of serum-soluble HLA-B27 antigen by ELISA.

An ELISA using serum as soluble HLA antigen source was developed for HLA-B27 typing. Two sandwich assays were run in parallel. The first assay utilized a monoclonal antibody (mAb) reacting with a determinant expressed by both HLA-B7 and B27 antigens; the other assay utilized a mAb reactive with HLA-B7 antigens but not with HLA-B27 antigens. After incubation with serum samples, bound HLA antigen was detected using an anti-beta 2m antibody conjugated to peroxidase and a chromogenic substrate. Absorbance of each well was measured at 490 nm. Based on analysis of absorbances obtained with panels of specimens of known HLA phenotypes, a mathematical algorithm was developed to derive the specimen HLA-B27 phenotype from its ELISA absorbance values. Despite the lack of monospecific mAb, an accurate HLA-B27 typing was possible. 362 specimens (including 151 HLA-B27-positive) were tested. Agreement between microlymphocytotoxicity and ELISA was 99.2%. No correlation between the level of HLA-B27 antigen reactivity and the amount of total HLA class I antigen in serum was observed. This report demonstrates the possibility of using serum-soluble HLA antigen and ELISA technology for histocompatibility testing. The assay offers several significant advantages over microlymphocytotoxicity: no need for cell preparation, batch testing capabilities and objective, reproducible interpretation of results.

Retroviruses released from a human tumor xenograft in nude mice induce colony-stimulating factor (CSF) activity in human fibroblastic cells.

A human colony-stimulating factor (CSF)-producing tumor transplanted into athymic nude mice released retroviruses in vitro. The viruses induced CSF activity in human fibroblastic cell lines.

A new semisynthetic 7alpha-methoxycephalosporin, CS-1170: 7beta-((cyanomethyl)thio)acetamido)-7alpha-methoxy-3-((1-methyl-1H-tetrazol-5-yl)thio)methyl)-3-cephem-4-carboxylic acid.

The synthesis and antimicrobial activity of a new semisynthetic 7alpha-methoxycephalosporin,7beta [[(cyanomethyl)thiol]acetamidol]-7alpha-methoxy-3-[[(1-methyl-1H-tetrazol-5-yl)thio]-methyl]-3-cephem-4-carboxylic acid (CS-1170), are described. This compound shows interesting antibacterial activity when compared to cefoxitin and cephalothin.