Evidence for a major gene influence on persistent developmental stuttering

Stuttering is a complex developmental speech disorder of unknown etiology. There is a substantial aggregation of stuttering in families, suggesting a genetic component to the disorder. However, the exact mode of transmission is still unknown. An earlier study of 56 multigenerational pedigrees ascertained through single adult probands (38 males and 18 females) found that biological relatives of persistent developmental stutterers have an approximately 10-fold higher risk than in the general population; risk is higher for male relatives, and proband's sex does not affect recurrence and relative risks. In the present paper we conduct a complex segregation analysis of the same data, using the logistic regression model of the SAGE software. Based on the comparisons of model likelihoods, the Mendelian model was selected over all other nongenetic models and the general transmission model. This model was further refined into the most parsimonious model, which shows an autosomal dominant major gene effect influenced by two covariates: sex and affection status of parents. With this model applied to 47 informative multiplex pedigrees, a power calculation based on linkage simulation produced an average lod score of 6.8 for 10-cM density genome scan markers. These results give impetus for a genomewide linkage analysis of susceptibility to persistent developmental stuttering.     

Biomolecule-embedded metal-organic frameworks as an innovative sensing platform

Technological advancements combined with materials research have led to the generation of enormous types of novel substrates and materials for use in various biological/medical, energy, and environmental applications. Lately, the embedding of biomolecules in novel and/or advanced materials (e.g., metal-organic frameworks (MOFs), nanoparticles, hydrogels, graphene, and their hybrid composites) has become a vital research area in the construction of an innovative platform for various applications including sensors (or biosensors), biofuel cells, and bioelectronic devices. Due to the intriguing properties of MOFs (e.g., framework architecture, topology, and optical properties), they have contributed considerably to recent progresses in enzymatic catalysis, antibody-antigen interactions, or many other related approaches. Here, we aim to describe the different strategies for the design and synthesis of diverse biomolecule-embedded MOFs for various sensing (e.g., optical, electrochemical, biological, and miscellaneous) techniques. Additionally, the benefits and future prospective of MOFs-based biomolecular immobilization as an innovative sensing platform are discussed along with the evaluation on their performance to seek for further development in this emerging research area.     

GnRH in non-hypothalamic reproductive tissues

Gonadotropin releasing hormone (GnRH) is a hypothalamic neuronal secretory decapeptide that plays a pivotal role in mammalian reproduction. GnRH and its analogues are used extensively in the treatment of hormone dependent diseases and assisted reproductive technology. Fourteen structural variants and three different forms of GnRH, named as hypothalamic GnRH or GnRH-I, mid brain GnRH or GnRH-II and GnRH-III across various species of protochordates and vertebrates have been recognised. The hormone acts by binding to cell surface transmembrane G protein coupled receptors (GPCRs) and activates Gq/11 subfamily of G proteins. Although hypothalamus and pituitary are the principal source and target sites for GnRH, several reports have recently suggested extra-hypothalamic GnRH and GnRH receptors in various reproductive tissues such as ovaries, placenta, endometrium, oviducts, testes, prostrate, and mammary glands. GnRH-II appears to be predominantly expressed in extra pituitary reproductive tissues where it produces its effect by PLC, PKA2, PLD, and AC cell signalling pathways. In these tissues, GnRH is considered to act by autocrine or paracrine manner and regulate ovarian steroidogenesis by having stimulatory as well as inhibitory effect on the production of steroid hormones and apoptosis in ovarian follicle and corpus luteum. In male gonads, GnRH has been shown to cause a direct stimulatory effect on basal steroidogenesis and an inhibitory effect on gonadotropin-stimulated androgen biosynthesis. Recent studies have shown that GnRH is more abundantly present in ovarian, endometrial and prostrate carcinomas. The presence of type-II GnRH receptors in reproductive tissues (e.g. gonads, prostrate, endometrium, oviduct, placenta, and mammary glands) suggests existence of distinct role(s) for type-II GnRH molecule in these tissues. The existence of different GnRH forms indicates the presence of distinctive cognate receptors types in vertebrates and is a productive area of research and may contribute to the development of new generation of GnRH analogues with highly selective and controlled action on different reproductive tissues and the target-specific GnRH analogues could be developed.     

DNA barcodes for marine fungal identification and discovery

We employed DNA barcodes for identification of fungal species in marine sediments. Sediments were collected seasonally along the Southeast coast of India from which a culturable fungal library was constructed. All cultured species were morphologically documented using microscopical analysis. A maximum population density of 19.3 × 10³ CFU/g was recorded in monsoon and minimum of 3 × 10³ CFU/g in premonsoon season. Two-way analysis of variance suggests that the fungal community varied significantly between the seasons (F = 9.543, P < 0.001) and at various depths sampled (F = 4.655, P < 0.05). In total, 54 fungal species belonging to 13 different families were documented and all species were sequenced for internal transcribed spacer genes. Each species was represented by at least two specimens constituting a total of 171 specimens for DNA barcoding. Twelve species of a marine fungi were sequenced for the first time. Branching patterns of phylogenetic tree strongly supported the sequence variations within and between all species barcoded. Based on the pairwise distance model we suggest barcode gaps of 15 %, 21 %, 30 %, 35 % and 51 % for genera, family, order, class and phyla respectively.     

Evaluation of insecticidal properties of botanicals for sustainable management of sucking pests of horticultural crops

Aphids, thrips, whiteflies, mealy bugs and mites could cause significant yield losses in horticultural crops. Many synthetic chemicals highly hazardous to non-target organisms and the environment are in use in their management. Botanicals are ideal for safe sustainable pest management by keeping synthetic chemical use at a minimum. We studied the insecticidal properties of three botanicals viz., Annona squamosa, Ricinus communis and Sapindus mukorossi seed extracts against sucking pests viz., aphids (Aphis gossypii and Aphis craccivora) on okra (Abelmoschus esculentus) and bittergourd (Momordica charantia), thrips (Scirtothrips dorsalis) on chilli (Capsicum frutescens), whiteflies (Bemisia tabaci) on eggplant (Solanum melongena), mealy bugs (Maconellicoccus hirsutus) on betel vine (Piper betle) and mites (Tetranychus urticae) on eggplant (Solanum melongena) under laboratory conditions. The bioassay showed that A. squamosa seed extract has potent insecticidal properties on all sucking pests, except T. urticae. Though S. mukorossi seed extract exhibited no insecticidal property, had a significant acaricidal property. A. squamosa and S. mukorossi seed extracts will therefore be additional botanicals for use in organic farming for managing the sucking pests effectively.