Showing papers by "North Eastern Hill University published in 2012"
TL;DR: The study delineated the potential habitats in the higher elevations of Khasi hills within the current home range where the species can be reintroduced, indicating the importance of flowering stage in determining the species distribution.
173 citations
TL;DR: A systematic review of the consequences of this widespread habit of BN/BQ mastication on oral cancer with a clinical perspective looks at various preventive efforts being made by governments and highlights the multifaceted intervention strategies required to mitigate and/or control the habit.
Abstract: Betel nut (BN), betel quid (BQ) and products derived from them are widely used as a socially endorsed masticatory product The addictive nature of BN/BQ has resulted in its widespread usage making it the fourth most abused substance by humans Progressively, several additives, including chewing tobacco, got added to simple BN preparations This addictive practice has been shown to have strong etiological correlation with human susceptibility to cancer, particularly oral and oropharyngeal cancers
The PUBMED database was searched to retrieve all relevant published studies in English on BN and BQ, and its association with oral and oropharyngeal cancers Only complete studies directly dealing with BN/BQ induced carcinogenesis using statistically valid and acceptable sample size were analyzed Additional relevant information available from other sources was also considered
This systematic review attempts to put in perspective the consequences of this widespread habit of BN/BQ mastication, practiced by approximately 10% of the world population, on oral cancer with a clinical perspective BN/BQ mastication seems to be significantly associated with susceptibility to oral and oropharyngeal cancers Addition of tobacco to BN has been found to only marginally increase the cancer risk Despite the widespread usage of BN/BQ and its strong association with human susceptibility to cancer, no serious strategy seems to exist to control this habit The review, therefore, also looks at various preventive efforts being made by governments and highlights the multifaceted intervention strategies required to mitigate and/or control the habit of BN/BQ mastication
162 citations
TL;DR: It is indicated that silver nanoparticles synthesized using soil borne indigenous fungus of high altitudes show considerable antimicrobial activity, deserving further investigation for potential applications.
Abstract: Fifty three fungi isolated from soils of different microhabitats of eastern Himalayan range (3,400~3,600 msl) were screened for mycosynthesis of silver nanaoparticles (AgNPs) and their efficacy as antimicrobials were assessed in combination with commonly used antibiotics. Three isolates Aspergillus terreus SP5, Paecilomyces lilacinus SF1 and Fusarium sp. MP5 identified based on morphological and 18S rRNA gene sequences were found to synthesize AgNPs. These nanoparticles were characterized by visual observation followed by UV-visible spectrophotometric analysis. The AgNPs synthesized by Aspergillus terreus SP5, Paecilomyces lilacinus SF1 and Fusarium sp. MP5 showed absorbance maxima at 412, 419, and 421 nm respectively in the visible region. Transmission electron microscopy micrograph showed formation of spherical AgNPs of 5~50 nm size. The antimicrobial activity of the mycosynthesized nanoparticles were investigated alone and in combination with commonly used antibiotics for analysis of growth inhibition zone against test organisms, namely, Staphylococcus aureus MTCC96, Streptococcus pyogenes MTCC1925, Salmonella enterica MTCC735 and Enterococcus faecalis MTCC2729. The mycosynthesized nanoparticles showed potent antibacterial activity and interestingly their syngergistic effect with erythromycin, methicillin, chloramphenicol and ciprofloxacin was significantly higher as compared to inhibitions by AgNPs alone. The present study indicates that silver nanoparticles synthesized using soil borne indigenous fungus of high altitudes show considerable antimicrobial activity, deserving further investigation for potential applications.
108 citations
TL;DR: Floodwaters are often supersaturated with dissolved CO2 enabling photosynthesis by submerged terrestrial plants, although rates remain well-below those in air.
Abstract: Background and aims
Dendrobium hookerianum is a rare and threatened epiphytic orchid of northeast India. Prospects for conservation would be strengthened by developing an in vitro method for mass propagation. Seeds are minute and difficult to use directly in the field for this purpose, being non-endospermous with a low nutrient content and dependent on a specific fungus for germination and early seedling development. Although produced in large numbers (2–3 million per capsule), <5 % germinate naturally in the wild. Our objective was to develop a rapid and successful method for in vitro propagation based on an initial in vitro asymbiotic seed germination step that achieved high percentages.
58 citations
TL;DR: An attempt to evaluate the antimicrobial and antioxidant activity of fungal endophytes inhabiting Emblica officinalis has been made keeping in view the medicinal importance of the selected host plant in Indian traditional practices.
Abstract: In the present study, an attempt to evaluate the antimicrobial and antioxidant activity of fungal endophytes inhabiting Emblica officinalis has been made keeping in view the medicinal importance of the selected host plant in Indian traditional practices. A total of four endophytic fungi belonging to Phylum Ascomycetes were isolated from different parts of the plant which were characterized morphologically and by using rDNA-internal transcribed spacer. The most frequently isolated endophyte was Phomopsis sp. The antioxidant activity by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power assay, and total phenol were evaluated using ethanolic extract of endophytic fungi. DPPH activities in all the ethanolic extract increased with the increase in concentrations. Endophytes, Phomopsis sp. and Xylaria sp. showed highest antioxidant activity and also had the higher levels of phenolics. Antimicrobial activity of fungal extract were tested against four bacteria namely, Escherichia coli MTCC730, Enteroccocus faecalis MTCC2729, Salmonella enterica ser. paratyphi MTCC735 and Streptococcus pyogenes MTCC1925, and the fungus Candida albicans MTCC183. In general, the fungal extracts inhibited the growth of test organisms except E. coli.
52 citations
TL;DR: EV method proved to be most appropriate way to cryopreserve the PLBs of D. nobile and regenerated plantlets showed normal morphology as that of control plants.
Abstract: An efficient protocol for cryopreservation of protocorm like bodies (PLBs) of Dendrobium nobile, based on encapsulation–dehydration (ED) and encapsulation–vitrification (EV), was established. In both cryogenic procedures, PLBs were initially osmoprotected with a mixture of 0.4 M sucrose and 2 M glycerol, incorporated in the encapsulation matrix [comprising 3% (w/v) sodium alginate and 0.1 M CaCl2]. Out of the two methods, EV resulted in higher survival (78.1%) and regrowth (75.9%) than ED (53.3 and 50.2% respectively). Incorporation of 0.4 M sucrose and 2 M glycerol in the encapsulation matrix resulted in higher survival percentage after cryopreservation. In both the cases (ED and EV), shoots regenerated from cryopreserved PLBs with an intermediary PLB formation. Regenerated shoots were successfully rooted in the medium containing 1.5 mg/l Indole-3 butyric acid. Successful acclimatization of plantlets was obtained in the compost containing brick pieces and charcoal chunks (1:1) + a top layer of moss with a maximum survivability (82%). EV method proved to be most appropriate way to cryopreserve the PLBs of D. nobile. Regenerated plantlets showed normal morphology as that of control plants.
52 citations
TL;DR: The present investigation was undertaken to propagate D. longicornu, a medicinally important orchid using axillary bud segments, which could help in conserving other threatened orchids as well.
Abstract: Background and aims Dendrobium longicornu, commonly known as the ‘Long-horned Dendrobium’, is an endangered and medicinally important epiphytic orchid. Over-exploitation and habitat destruction seriously threaten this orchid in Northeast India. Our objective was to develop an efficient protocol for the mass propagation of D. longicornu using axillary bud segments. Methodology and principal results Axillary buds cultured in Murashige and Skoog semi-solid medium supplemented with a-naphthalene acetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 6-benzylaminopurine (BAP) readily developed into plantlets. These formed either directly from shoot buds or from intermediary protocorm-like bodies (PLBs). The maximum explant response (86.6 %) was obtained in medium supplemented with NAA at 30 mM, while the maximum number of shoots (4.42) and maximum bud-forming capacity (3.51) were observed in medium containing 15 mM BAP and 5 mM NAA in combination. Protocorm-like bodies were obtained when the medium contained 2,4-D. The maximum number of explants forming PLBs (41.48 %) was obtained in medium containing 15 mM BAP and 15 mM 2,4-D. Well-developed plantlets obtained after 20 –25 weeks of culture were acclimatized and eventually transferred to the greenhouse. Over 60 % of these survived to form plants � 3 – 4 cm tall after 90 days in glasshouse conditions using a substrate of crushed brick and charcoal, shredded bark and moss. Conclusions The method described can readily be used for the rapid and large-scale regeneration of D. longicornu. Its commercial adoption would reduce the collection of this medicinally important and increasingly rare orchid from the wild.
50 citations
TL;DR: The results of this study indicate that leaf extract of L. spinosa possesses significant anthelminthic efficacy against the adult stages and migrating larvae of T. spiralis, and the encysted muscle larvae of parasite are comparatively less sensitive to L.spinosa leaf extract treatment.
Abstract: Trichinellosis is a widespread zoonoses for which no effective drug treatment is available at this time. Though anthelmintics such as mebendazole and albendazole are commonly used to treat human trichinellosis, none of these drugs are fully effective against the encysted or new-born larvae of Trichinella spiralis. In recent years, there has been a growing interest in developing newer anthelminthics from medicinal plants, particularly the ones used in traditional medicines in many parts of the world, due to the increasing spread of anthelminthic resistance and/or decreasing activity against encapsulated larval stages of parasites. The aim of the present study was to investigate the efficacy of leaf extract of Lasia spinosa (Araceae) against different life cycle stages of T. spiralis, i.e. adult (days 3 and 4 post-infection), migrating larvae (days 8, 9 and 10 post-infection) and encysted muscle larvae (days 31–37 post-infection). The study showed that L. spinosa leaf extract is effective against all the three life cycle stages of parasite. Against the adult stage, an oral administration of plant extract at 800 mg/kg dose revealed a 75.30% reduction in the number of adult worms, as compared to untreated controls at day 10 post-infection. Whereas against migrating larvae, the same dose of plant extract given for 3 days, reduced the number of larvae recovered from musculature of treated animals by 72.23%. However, in comparison of preceding two stages, the extract showed comparatively less efficacy against the encysted larvae of parasite. In this case, the 800 mg/kg dose of extract given for 7 days (after 30 day of post-infection) revealed only 64.84% reduction in the number of encysted larvae, as was evident from larval count on day 49 post-infection. Therefore, the results of this study indicate that leaf extract of L. spinosa possesses significant anthelminthic efficacy against the adult stages and migrating larvae of T. spiralis. On the other hand, the encysted muscle larvae of parasite are comparatively less sensitive to L. spinosa leaf extract treatment.
50 citations
TL;DR: The present investigation was undertaken to mass propagate Cymbidium mastersii, an ornamental orchid of Northeast India by in vitro propagation method, which could help for the conservation as well as commercialization of C. mastersii and other threatened and Ornamental orchids.
Abstract: Background and aims Cymbidium mastersii is an epiphytic orchid distributed mainly in Northeast India. Owing to its high commercial value in the floricultural industry, natural populations are under threat from over-exploitation. Mass propagation provides an alternative means of satisfying the demand. Unfortunately, conventional propagation is slow and difficult, suggesting in vitro methods for mass multiplication may be more appropriate. The objective of this study was to develop an efficient protocol. Methodology and principal results Four nutrient media were evaluated for seed germination and early protocorm development: Murashige and Skoog (MS), half-strength MS, Knudson ‘C’ (KC), and Vacin and Went (VW). In addition, the effects of plant growth regulators 6-benzylaminopurine (BAP), kinetin (KN), a-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA) were studied alone and in combination. The maximum percentage seed germination (93.58+ 0.56) was obtained in MS basal medium after 8 –9 weeks of culture. Secondary protocorms (protocorm-like bodies) were developed from primary protocorms on MS medium fortified with different concentrations and combinations of cytokinins (BAP and KN) and auxins (NAA and IBA). The highest numbers of secondary protocorms (20.55+ 0.62)/primary protocorms were obtained in MS medium supplemented with 5.0 mM BAP and 2.5 mM NAA. The most effective auxin source promoting root production (7.46+ 0.09 per shoot) was 10.0 mM IBA. The plants were acclimatized effectively (survival percentage 88 %) in a greenhouse using a rooting medium of crushed sterile brick and charcoal (1 : 1 v/v) and vermicompost (leaf litter + cow dung, 1 : 1 v/v). Conclusions An efficient protocol was established for in vitro propagation of C. mastersii using seed as the starting material. The percentage seed germination varied with the composition of the nutrient media and was highest in full-strength MS basal medium. The number of secondary protocorms that developed from primary protocorms was increased by the addition of 5.0 mM BAP and 2.5 mM NAA. In vitro raised plantlets acclimatized in a greenhouse were closely similar to the mother plants in morphology.
46 citations
TL;DR: The isolated bioactive compound was characterized to be cantharidin which showed potent antitumor activity and inhibited the proliferation of Ehrlich ascites carcinoma, both in vivo and in vitro.
Abstract: The anticancer activity of the extract of blister beetle, Mylabris cichorii has been documented earlier by us. In the present study, the active principle of M. cichorii was isolated and its anticancer efficacy was evaluated against murine Ehrlich ascites carcinoma (EAC). The isolated bioactive compound was characterized to be cantharidin which showed potent antitumor activity and inhibited the proliferation of Ehrlich ascites carcinoma, both in vivo and in vitro. Cantharidin-treated EAC-bearing mice showed about 82% increase in lifespan at the dose of 0.5 mg/kg/day. In vitro cytotoxicity assay with the 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test revealed about 50% cell death at the concentration of 25.8 μg/ml. The fluorescence and transmission electron microscopy revealed that EAC cells treated with cantharidin depicted typical apoptotic morphology with chromatin condensation, nuclear fragmentation into discrete masses, and plasma membrane blebbing which deduce towards the death of these cells. Histological examination of the kidney of cantharidin-treated mice showed glomerular and tubular congestion with abnormal Bowman’s capsule, thus, indicating a renal toxicity in the host. Cantharidin-induced renal damage in the host was also manifested by the decreased lactate dehydrogenase isozymes and its possible release from the cells.
45 citations
TL;DR: In this paper, the superoxide dismutase and catalase mimetic EUK-207 was given by subcutaneous injection (20 mg/kg/day, 5 days per week, once daily) starting at 7 days after irradiation and stopping before pneumonitis developed.
Abstract: In the event of a radiological accident or terrorist attack, whole- or partial-body exposure can injure the lungs. To simulate such an incident, we used a single fraction of total-body irradiation (TBI) or whole-thoracic irradiation to induce pneumonitis or pulmonary fibrosis, respectively, in a rat model. The superoxide dismutase and catalase mimetic EUK-207 was given by subcutaneous injection (20 mg/kg/day, 5 days per week, once daily) starting at 7 days after irradiation and stopping before pneumonitis developed. After TBI, morbidity and the increase in breathing rates associated with pneumonitis were significantly improved in rats treated with EUK-207 compared to rats receiving irradiation alone. At 42 days after TBI (the peak of pneumonitis) changes in vascular end points including pulmonary hemodynamics ex vivo and relative arterial density in lungs were also mitigated by EUK-207. At 7 months after whole-thoracic irradiation, EUK-207 reduced synthesis of collagen as assessed by the Sircol collagen assay and Masson's trichrome staining. Our results demonstrate promise for EUK-207 as a mitigator of radiation pneumonitis and fibrosis. We also demonstrate for the first time mitigation of multiple vascular injuries in the irradiated lung in vivo by EUK-207.
TL;DR: The present system is an example, which is first of its kind, of a case where hydrogen bonding with surfactant and solvent molecules results in a surface tension break.
Abstract: The dependence of critical micelle concentration (cmc) of sodium dioctylsulfosuccinate (AOT) on the amount of ethylene glycol (EG) in water + EG medium was reported to be unusual and different from that of other surfactants to the extent that the cmc of AOT in EG is lower than in water. It is yet to be understood why AOT behaves so in water + EG medium, although AOT is known to have some special properties. Hence in the present study cmc of AOT in water + EG medium in the range from 0 to 100% (by weight) EG is measured by using surface tension and fluorescence emission methods. In contrast to what was reported, this study revealed that with respect to EG amount the cmc of AOT follows the general trend and AOT has higher cmc in EG than in water. On the other hand, it was surprisingly found that a break in the surface tension isotherm occurs in the premicellar region when the amount of EG exceeds 50% rendering a bisigmoidal shape to the surface tension isotherm. UV spectral study showed that AOT and EG undergo hydrogen bonding in the premicellar region when the EG amount is ≥50% and this hydrogen bonding becomes less on adding NaCl. The density functional theory calculations also showed formation of hydrogen bonds between EG and AOT through the sulfonate group of AOT providing thereby support to the experimental findings. The calculations predicted a highly stable AOT-EG-H(2)O trimer complex with a binding energy of -37.93 kcal mol(-1). The present system is an example, which is first of its kind, of a case where hydrogen bonding with surfactant and solvent molecules results in a surface tension break.
TL;DR: Four new triphenyltin(IV) complexes of composition Ph(3)SnLH (where LH=2-/4-[(E)-2-(aryl)-1-diazenyl]benzoate) (1-4) were synthesized and characterized by spectroscopic techniques in combination with elemental analysis, indicating a tetrahedral coordination geometry in non-coordinating solvents.
TL;DR: The mechanism, kinetics and thermochemistry of the gas-phase reactions between CHF2OCHF2 and OH radical are investigated using the high level ab initio G2(MP2) and hybrid density functional model MPWB1K quantum chemical methods.
Abstract: The mechanism, kinetics and thermochemistry of the gas-phase reactions between CHF(2)OCHF(2) (HFE-134) and OH radical are investigated using the high level ab initio G2(MP2) and hybrid density functional model MPWB1K quantum chemical methods. Two relatively close in energy conformers are found for CHF(2)OCHF(2) molecule; both of them are likely to be important in the temperature range (250-1000 K) of our study. The hydrogen abstraction pathway for both the conformers with OH radical is studied and the rate constants are determined for the first time in a wide temperature range of 250 - 1000 K. The G2(MP2) calculated total rate constant value of 2.9 × 10(-15) cm(3) molecule(-1) s(-1) at 298 K is found to be in very good agreement with the reported experimental value of 2.4 × 10(-15) cm(3) molecule(-1) s(-1) at 298 K. The heats of reaction for CHF(2)OCHF(2) + OH reaction is computed to be -13.2 kcal mol(-1). The atmospheric lifetime of CHF(2)OCHF(2) is expected to be around 12 years.
TL;DR: In this paper, the issues and concerns of Indian rural credit, which is a powerful tool for enhancing production and productivity and for poverty alleviation, are analyzed in detail and some of the strategies adopted by Reserve Bank of India (RBI) to increase the rural credit facilities in the rural area of India.
Abstract: Purpose – The purpose of this paper is to analyse the issues and concerns of Indian rural credit, which is a powerful tool for enhancing production and productivity and for poverty alleviation. Further it highlights some of the strategies adopted by Reserve Bank of India (RBI) to increase the rural credit facilities in the rural area of India.Design/methodology/approach – The various tools of rural credit are analysed in detail. The Regional Rural Bank (RRB) who play a vital role in increasing the rural credits is studied. Self Help Group (SHG)‐Bank Linkage model of NABARD which creates an interface of the informal arrangements of the poor with the banking system is also analysed in detail.Findings – Rural credits serve as a tool for providing a sustainable livelihood for millions of rural Indians who don't have a means of livelihood. Several organisations like RRBs, Microfinance Institutions, NABARD, etc. are playing a major role in providing rural credit facilities to rural India. Reserve Bank of India ...
TL;DR: This study is mainly concentrated with plants used to cure diseases and to enquire about different healing systems, mainly herbal medicines used in the treatment of various ailments in Assam and Arunachal Pradesh.
TL;DR: An efficient regioselective protocol for the C-C bond formation by the unexpected α,α-diarylation of aromatic ketones with unactivated arenes in the presence of selenium dioxide and boron trifluoride etherate has been developed.
Abstract: An efficient regioselective protocol for the C–C bond formation by the unexpected α,α-diarylation of aromatic ketones with unactivated arenes in the presence of selenium dioxide and boron trifluoride etherate has been developed. The generality and functional tolerance of this protocol is demonstrated by the synthesis of a series of triarylethanones.
TL;DR: Mycelial biomass generation and root colonization, in addition to the enzyme activity of the endophytic fungal isolates, provided insights into their probable origin and ecological roles within the plant host.
Abstract: Fungal species that establish an endophytic role inside the tissues of medicinal plants are known to produce a wide range of biologically active metabolites and enzymes In the present study, the most dominant and representative endophytic fungal species of five ethno-medicinal plants prevalent in the pristine sacred forests of Meghalaya, were screened for their ability to produce amylase, cellulase, protease, lipase, and xylanase Each of endophytic fungal isolates showed a wide range of enzyme activity Mycelial biomass generation and root colonization, in addition to the enzyme activity of the endophytic fungal isolates, provided insights into their probable origin and ecological roles within the plant host
TL;DR: This study validates the utility of ITS rDNA region as a reliable indicator of phylogenetic relationships, especially ITS 2 as probable DNA barcode at higher levels and can serve as an additional approach for identification of broader range of plant taxa especially orchids.
TL;DR: In this article, the authors synthesized perpendicular SiOx nanowire arrays on Si substrates and investigated them using scanning electron microscopy and energy-dispersive spectroscopy.
Abstract: We have synthesized perpendicular SiOx nanowire (NW) arrays on Si substrates and investigated them using scanning electron microscopy. Transmission electron microscopy and energy-dispersive spectroscopy have been used to investigate the single NW structure. A near-infrared emission at 700 nm is observed. In/SiOx NW and In/SiOx thin film (TF) contacts exhibit Schottky behavior. The SiOx NW-based devices show six-fold improvements in photodetection efficiency in white-light illumination, compared to SiOx TF-based devices under reverse bias condition.
TL;DR: The present study has compiled and enlisted the antimalarial plants of northeast India, which would help future workers to find out the suitable antimalaria plants by thorough study.
TL;DR: In this paper, the effect of the addition of 2-methoxyethanol on the critical micelle concentration and on the degree of counterion dissociation of butanediyl-1,4-bis (tetradecyldimethylammonium bromide) gemini surfactant, [C14H29N+(CH3)2−(CH2)4−N+N+C 14H29,2Br−] (referred as 14−4−14, 2Br−), has been studied by varying the compositions
Abstract: The effect of the addition of 2-methoxyethanol on the critical micelle concentration (cmc) and on the degree of counterion dissociation (α) of butanediyl-1,4-bis(tetradecyldimethylammonium bromide) gemini surfactant, [C14H29N+(CH3)2–(CH2)4–N+(CH3)2C14H29,2Br−] (referred as 14–4–14,2Br−), has been studied by varying the compositions of the 2-methoxyethanol + water mixed solvent media (0 to 50 %) To determine various thermodynamic parameters of micellization, on the basis of the mass–action model for micelle formation, the experiments were performed at selected compositions of the mixed solvent at four temperatures ranging between 25 °C and 50 °C Furthermore, the air/bulk surface tensions of the pure and mixed media were determined, and a successful attempt was made to correlate the cohesive energy density described through the Gordon parameter with the values of Gibbs energy of micellization
TL;DR: The study provides the molecular characterization based on primary sequence data of the rDNA ITS2 region of the gastrothylacid amphistome flukes and demonstrates the phylogenetic utility of the ITS2 sequence–secondary structure data for inferences at higher taxonomic levels.
Abstract: Members of the family Gastrothylacidae (Trematoda: Digenea: Paramphistomata) are parasitic in ruminants throughout Africa and Asia. In north-east India, five species of pouched amphistomes, namely Fischoederius cobboldi, F. elongatus, Gastrothylax crumenifer, Carmyerius spatiosus and Velasquezotrema tripurensis, belonging to this family have been reported so far. In the present study, the molecular phylogeny of these five gastrothylacid species is derived using the second internal transcribed spacer (ITS2) sequence and secondary structure analyses. ITS2 sequence analysis was carried out to see the occurrence of interspecific variations among the species. Phylogenetic analyses were performed for primary sequence data alone as well as the combined sequence-structure information using neighbour-joining and Bayesian approaches. The sequence analysis revealed that there exist considerable interspecific variations among the various gastrothylacid fluke species. In contrast, the inferred secondary structures for the five species using minimum free energy modelling showed structural identities, in conformity with the core four-helix domain structure that has been recently identified as common to almost all eukaryotic taxa. The phylogenetic tree reconstructed using combined sequence-structure data showed a better resolution, as compared to the one using sequence data alone, with the gastrothylacid species forming a monophyletic group that is well separated from members of the other family, Paramphistomidae, of the amphistomid flukes group. The study provides the molecular characterization based on primary sequence data of the rDNA ITS2 region of the gastrothylacid amphistome flukes. Results also demonstrate the phylogenetic utility of the ITS2 sequence-secondary structure data for inferences at higher taxonomic levels.
01 Mar 2012
TL;DR: An in vitro regeneration protocol was developed for Capsicum chinense Jacq.
Abstract: An in vitro regeneration protocol was developed for Capsicum chinense Jacq. cv. Naga King Chili, a very pungent chili cultivar and an important horticultural crop of Nagaland (Northeast India). Maximum number of shoot (13 ± 0.70) was induced with bud-forming capacity (BFC) index of 10.8, by culturing nodal segments in Murashige and Skoog (MS) medium supplemented with 18.16 μM Thidiazuron (TDZ) followed by 35.52 μM 6-benzylaminopurine (BAP). Using shoot tips as explants, multiple shoot (10 ± 0.37) (BFC 8.3) was also induced in MS medium fortified with either 18.16 μM TDZ or 35.52 μM BAP. Elongated shoots were best rooted in MS medium containing 5.70 μM indole-3-acetic acid (IAA). Rooted plantlets thus developed were hardened in 2–3 weeks time in plastic cups containing potting mixture of a 1:1 mix of soil and cow dung manure and then subsequently transferred to earthen pots. The regenerated plants did not show any variation in the morphology and growth as compared to the parent plant.
TL;DR: The QTAIM analysis was found to be able to uniquely distinguish between the ground and excited states of the OHBA molecule as well as both determining the effects on the bonding character of adding different substituent groups and differentiating between the ESIPT reactions in the SA and MS molecules.
Abstract: Excited state intramolecular proton transfer (ESIPT) reaction along the O-H⋅⋅⋅⋅O hydrogen bond of o-hydroxy benzaldehyde (OHBA), methyl salicylate (MS) and salicylic acid (SA) was investigated by ab-initio quantum chemical calculation and theory of atoms and molecules (QTAIM) for the first time. Variation in several geometric as well as QTAIM parameters along the reaction coordinate was monitored in the fully relaxed excited state potential energy curve (PEC) obtained from intrinsic reaction coordinate (IRC) analysis. Although, the excited state barrier height for the forward reaction (∆E
0
#
) reduces substantially in all the systems, MS and SA do not show any obvious asymmetry for proton transfer. For MS and SA, the crossover of the bond index as well as the lengths of the participating bonds at the saddle point is assigned due to this symmetry in accordance with bond energy – bond order (BEBO) model, which does not hold true in OHBA both in the ground and excited states. Bond ellipticity, covalent and metallic character were examined for different structures along the reaction path within the QTAIM framework. The QTAIM analysis was found to be able to uniquely distinguish between the ground and excited states of the OHBA molecule as well as both determining the effects on the bonding character of adding different substituent groups and differentiating between the ESIPT reactions in the SA and MS molecules.
TL;DR: Alkyl/benzyl azides can be readily synthesized in excellent yields from their corresponding alcohols by stirring a solution of sodium azide in DMSO with a thoroughly ground equimolecular mixture of triphenylphosphine, iodine and imidazole.
Abstract: Alkyl/benzyl azides can be readily synthesized in excellent yields from their corresponding alcohols by stirring a solution of sodium azide in DMSO with a thoroughly ground equimolecular mixture of triphenylphosphine, iodine and imidazole.
TL;DR: Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumulation of native oligarchic small tree species and a slow trend of shifting the population of Lamiaceae group by Moraceae species in secondary forests.
Abstract: Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging to 46 family, 103 genera and 144 species were counted at ≥30 cm DBH (diameter at breast height) using 28 permanent belt transects with a size of 1 ha (10 m × 1000 m). Four different tree communities were identified. The primary forests was dominated by Shorea robusta (mean density 464.77 trees·ha−1, 105 species) and Schima wallichii (336.25 trees·ha−1, 82 species), while the secondary forests was dominated by Tectona grandis (333.88 trees·ha−1, 105 species) and Hevea brasiliensis (299.67 trees·ha−1, 82 species). Overall mean basal area in this study was 18.01m2·ha−1; the maximum value was recorded in primary Shorea forest (26.21 m2·ha−1). Mean density and diversity indices were differed significantly within four different communities. No significant differences were observed in number of species, genera, family and tree basal cover area. Significant relationships were found between the species richness and different tree population groups across the communities. Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumulation of native oligarchic small tree species. Seventeen species were recorded with <2 individuals of which Saraca asoka (Roxb.) de Wilde and Entada phaseoloides (L.) Merr. etc. extensively used in local ethno-medicinal formulations. The present S. robusta Gaertn dominated forest was recorded richer (105 species) than other reported studies. Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests. Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur. The analysis of FIV suggested a slow trend of shifting the population of Lamiaceae group by Moraceae species in secondary T. grandis L. dominated community.
TL;DR: Findings indicate that ripe fruits of S. myriacanthum possess significant anthelmintic property, without any adverse effects to the experimental animals, which may provide a scientific rationale for the traditional use of this plant against intestinal worms.
Abstract: Although there are many effective drugs available to treat intestinal worms, the fact remains that they remain out of reach to a majority of the population in many areas of the world. On the other hand, traditional plant-based remedies continue to be an important therapeutic aid for treating worm infections throughout the world, especially in the developing nations. Solanum myriacanthum Dunal is a perennial shrub that is used in the folk medicine of Tangkhul Naga tribe of India for treating intestinal worms. This study evaluates the anthelmintic activity of its ripe fruit extract using experimental Hymenolepis diminuta (a zoonotic tapeworm) infections in albino rats. The efficacy of extract was adjudged by monitoring the eggs per gram (EPG) count of parasite as well as by the direct count of surviving worms in the intestine following treatment with methanol fruit extract of this plant to different groups of rats harbouring H. diminuta infections. The plant extract showed a dose-dependent reduction of both EPG as well as worm counts for all the developmental stages of H. diminuta in rats. However, the effects of the extract were more apparent on the adult stages than larval or immature stages of the parasite. Against the adult stage, a single oral dose of 800 mg/kg of extract, given for 3 days, showed 60.49% reduction in the EPG counts and 56.60% reduction in the worm counts in the extract-treated group as compared to untreated control. In comparison, the reference drug praziquantel (5 mg/kg) showed 51.81% and 70.00% reduction in the EPG and worm counts, respectively. The LD50 (oral) of the extract was determined to be 3,093.24 mg/kg in rats, and no significant changes were observed in the values of serum glutamate oxalate transaminase, serum glutamate pyruvate transaminase, cholesterol and total protein between the extract-treated and control groups of animals. These findings indicate that ripe fruits of S. myriacanthum possess significant anthelmintic property, without any adverse effects to the experimental animals. This may provide a scientific rationale for the traditional use of this plant against intestinal worms.
TL;DR: Eurotiales and Hypocreales were most diverse and abundant group of fungi along the entire altitudinal stretch and showed negative correlation with altitude and soil moisture content and soil temperature, pH, humidity and ambient temperature showed positive correlation with fungal distribution.
Abstract: Very few studies have addressed the phylogenetic diversity of fungi from Northeast India under the Eastern Himalayan range. In the present study, an attempt has been made to study the phylogenetic diversity of culturable soil fungi along the altitudinal gradients of eastern Himalayas. Soil samples from 24 m above sea level to 2,000 m above sea level altitudes of North-East India were collected to investigate soil micro-fungal community structure and diversity. Molecular characterization of the isolates was done by PCR amplification of 18S rDNA using universal primers. Phylogenetic analysis using BLAST revealed variation in the distribution and richness of different fungal biodiversity over a wide range of altitudes. A total of 107 isolates were characterized belonging to the phyla Ascomycota and Zygomycota, corresponding to seven orders (Eurotiales, Hypocreales, Calosphaeriales, Capnodiales, Pleosporales, Mucorales, and Mortierellales) and Incertae sedis. The characterized isolates were analysed for richness, evenness and diversity indices. Fungal diversity had significant correlation with soil physico-chemical parameters and the altitude. Eurotiales and Hypocreales were most diverse and abundant group of fungi along the entire altitudinal stretch. Species of Penicillium (D = 1.44) and Aspergillus (D = 1.288) were found to have highest diversity index followed by Talaromyces (D = 1.26) and Fusarium (D = 1.26). Fungal distribution showed negative correlation with altitude and soil moisture content. Soil temperature, pH, humidity and ambient temperature showed positive correlation with fungal distribution.
TL;DR: Results suggest that the activation of iNOS gene under hyper-ammonia stress was probably mediated through theactivation of one of the major transcription factors, the NFκB.