Quantitation of antibody uptake on A group erythrocytes using immunoautoradiography and monoclonal IgM anti-A

The number of antibody molecules on individual erythrocytes was counted in A1, A2, A3 B and A group individuals using immunoautoradiography (IAR) and monoclonal IgM anti-A1. Quantitation was also done for A group pregnant women. The number of antibody molecules on different red cells of an individual varied widely. Gross variations were also noted in cells of different individuals from one and the same group. The mean values of the uptake of the number of antibody molecules showed the following range A1 greater than A2 greater than Ax greater than A3B. When compared to the average for total A1 adults, red cells of pregnant women and newborn infants showed a 10.7% and 19.7% reduction respectively, in antibody uptake. The mean number of antibody molecules per A1 adult red cells was 5.6 +/- 3 X 10(4), while A2 had 0.85 +/- 0.35 X 10(4) molecules, thus showing a significant quantitative variation.     

Interpreting the role of phosphorus and growth rate in enhanced fungal induction of sesquiterpenes from Hyoscyamus muticus root cultures

The effect of thiamine limitation in combination with fungal elicitation on sesquiterpene (solavetivone) production was studied in Agrobacterium-transformed hairy-root cultures of Hyoscyamus muticus as a potential means of manipulating the growth rate independent of phosphorus availability. Limiting the initial supply of thiamine did not affect the growth of these cultures compared to growth at the control level of thiamine (0.01 g/l). There was also no enhancement in sesquiterpene production when thiamine supply was limited. Serial culturing in thiamine-free media suggests that these root cultures are not strictly auxotrophic for thiamine, in contrast to previously published results for untransformed root culture. The effect of phosphate limitation combined with elicitation on the production of solavetivone was examined at constant media volume to provide a constant elicitor concentration and to eliminate feedback-inhibition effects. Limiting the initial supply of phosphate to elicited cultures resulted in a twofold increase in solavetivone production as compared to the elicitation at control media phosphate levels (1.1mm). Because growth was attenuated, production per unit cell mass increased 11-fold compared to the control. The effect of phosphate limitation on solavetivone production at constant cell mass and elicitor per root mass was studied. Limiting the initial supply of phosphate to elicited cultures under these conditions did not result in enhanced production of solavetivone. The initially observed enhanced production of solavetivone at limiting initial phosphate concentrations is therefore due to factors other than the growth rate or phosphate involvement in secondary metabolism. Correspondence to: W. R. Curtis     

Chemodiversity and α-Glucosidase Activity of Eucalyptus Species from Northwestern Himalaya,India

The aim of current work was to determine essential oils (EOs) composition from three Eucalyptus species, including E. citriodora, E. camaldulensis and E. globulus and assess their α-glucosidase inhibitory activity. The EOs were collected using the hydrodistillation technique and characterized by GC/MS, GC-FID and NMR. The isolated EOs from leaves parts of Eucalyptus species varied from 0.56 to 1.0 % on fresh weight basis. The content of the EOs was distinct according to the species. The most abundant metabolites were identified as citronellal (0–83.0 %), 1,8-cineole (0.2–44.8 %), spathulenol (0.4–16.1 %) α-pinene (0.4–15.9 %), p-cymene (3.7–11.9 %), citronellol (0–8.6 %), β-eudesmol (5.3–8.6 %) and β-pinene (0–7.1 %). The EOs obtained from targeted samples exhibited strong α-glucosidase inhibitory activity. These results are encouraging and underline that the EOs of Eucalyptus species may be a promising alternative source of natural antidiabetic.     

Correlation between temperature range of growth and structural transitions in membranes and lipids of Escherichia coli K12

Purified cytoplasmic and outer membranes isolated from cells of wild-type Escherichia coli grown at different temperatures were labelled with 1,6-diphenyl-1,3,5-hexatriene and anlyzed using fluorescence polarization techniques. Lipids extracted from the membranes were similarly analyzed using fluorescence polarization. The thermotropic structural transition in outer membranes changed as a function of growth temperature. The structural transition in cytoplasmic membranes and lipids extracted from either cytoplasmic or outer membranes did not change with growth temperature. These data suggest that adaptive changes which occur in the outer membrane determine the temperature range of growth of E. coli. These changes apparently require alterations in outer membrane components other than phospholipids.     

Wrinkling instabilities for biologically relevant fiber-reinforced composite materials with a case study of Neo-Hookean/Ogden–Gasser–Holzapfel bilayer

Biomechanics and Modeling in Mechanobiology - Wrinkling is a ubiquitous surface phenomenon in many biological tissues and is believed to play an important role in arterial health. As arteries are...     

Origin and diversification of Indian Ceropegieae (Apocynaceae) and its possible relation to the Indian monsoon

The Indian subcontinent has experienced a major shift in climatic regime from a wet tropical regime to increased seasonal rainfall, since the late Miocene. This shift has been attributed to the intensification of monsoons, which led to opening up of dry habitats in humid forests and formation of deciduous forests. We explored the role of this climatic shift in the origin and diversification of dry‐adapted plant genera Ceropegia and Brachystelma (Ceropegiae, Asclepiadoideae, Apocynaceae). We sampled Ceropegia and Brachystelma from across India and used five markers (two nuclear and three plastid regions) to reconstruct a global phylogeny of this group. Indian members of the tribe Ceropegiae were derived from Africa through at least four independent dispersal events. All dispersal events occurred in late Miocene after establishment of a monsoon climate. One of these early dispersing lineages underwent rapid radiation in peninsular India, giving rise to around 50 species. Thus, both dispersal and diversification events coincided with the intensification of monsoons and concomitant aridification. The role of environment in the evolution of floral characteristics and root type in the Indian radiation is also discussed. This is one of the first reports on a dry‐adapted endemic radiation of plants in India.     

MAPK signaling regulates c‐MYC for melanoma cell adaptation to asparagine restriction

Amino acid restriction is among promising potential cancer treatment strategies. However, cancer cells employ a multitude of mechanisms to mount resistance to amino acid restriction, which impede the latter’s clinical development. Here we show that MAPK signaling activation in asparagine‐restricted melanoma cells impairs GSK3‐β‐mediated c‐MYC degradation. In turn, elevated c‐MYC supports ATF4 translational induction by enhancing the expression of the amino acid transporter SLC7A5, increasing the uptake of essential amino acids, and the subsequent maintenance of mTORC1 activity in asparagine‐restricted melanoma cells. Blocking the MAPK‐c‐MYC‐SLC7A5 signaling axis cooperates with asparagine restriction to effectively suppress melanoma cell proliferation. This work reveals a previously unknown axis of cancer cell adaptation to asparagine restriction and informs mechanisms that may be targeted for enhanced therapeutic efficacy of asparagine limiting strategies.     

Effect of different cultivation conditions and inducers on the production of laccase by the litter-dwelling fungal isolate Fusarium incarnatum LD-3 under solid substrate fermentation

The litter-dwelling fungus Fusarium incarnatum LD-3 has been identified as a novel producer of laccase. The present work was oriented towards the optimization of various cultivation conditions for maximizing laccase production under solid substrate fermentation. The process parameters were optimized by the “one factor at a time” approach. Maximum laccsase production was obtained at pH 5.0 and at a temperature of 28 °C with 60 % moisture content using rice bran as a substrate. The laccase production was enhanced in the presence of aromatic inducer, i.e. ortho-dianisidine at a concentration of 0.5 mM. Laccase production was further increased by 52.56 % when the medium was supplemented with 2 % (v/v) alcohol. Among the various amino acids tested as a growth factor and nitrogen source, D-Serine and DL-2 Amino n-butyric acid, DL-Alanine and L-Glycine were found to be the most suitable for laccase production. The highest laccase production (1,352.64 U/g) was achieved under optimized conditions, and was 2.1-fold higher than the unoptimized conditions. Thus, the novel litter-dwelling fungal isolate Fusarium incarnatum LD-3 seems to be an efficient producer of laccase and can be further exploited for biotechnological applications. This is the first report on the optimization of cultivation conditions and inducers for laccase production from Fusarium incarnatum LD-3.     

Novel method to differentiate 3T3 L1 cells in vitro to produce highly sensitive adipocytes for a GLUT4 mediated glucose uptake using fluorescent glucose analog

Adipocytes play a vital role in glucose metabolism. 3T3 L1 pre adipocytes after differentiation to adipocytes serve as excellent in vitro models and are useful tools in understanding the glucose metabolism. The traditional approaches adopted in pre adipocyte differentiation are lengthy exercises involving the usage of IBMX and Dexamethasone. Any effort to shorten the time of differentiation and quality expression of functional differentiation in 3T3 L1 cells in terms of enhanced Insulin sensitivity has an advantage in the drug discovery process. Thus, there is a need to develop a new effective method of differentiating the pre adipocytes to adipocytes and to use such methods for developing efficacious therapeutic molecules. We observed that a combination of Dexamethasone and Troglitazone generated differentiated adipocytes over fewer days as compared to the combination of IBMX and Dexamethasone which constitutes the standard protocol followed in our laboratory. The experiments conducted to compare the quality of differentiation yielded by various differentiating agents indicated that the lipid droplet accumulation increased by 112 % and the GLUT4 mediated glucose uptake by 137 % in cells differentiated with Troglitazone and Dexamethasone than in cells differentiated traditionally. The comparative studies conducted for evaluating efficient measurable glucose uptake by GOPOD assay, radioactive ³H-2-deoxy-D-glucose assay and by non-radioactive 6-NBDG (fluorescent analog of glucose) indicated that the non-radioactive method using 6-NBDG showed a higher signal to noise ratio than the conventional indirect glucose uptake method (GOPOD assay) and the radioactive ³H-2-deoxy-D-glucose uptake method. Differentiated 3T3 L1 cells when triggered with 2.5 ng/mL of Insulin showed 3.3 fold more glucose uptake in non-radioactive method over the radioactive ³H-2-deoxy-D-glucose uptake method. The results of this study have suggested that a combination of Dexamethasone and Troglitazone for 3T3 L1 cell differentiation helps in better quality differentiation over a short period of time with increased sensitivity to Insulin. The application of these findings for developing new methods of screening novel Insulin mimetics and for evaluating the immunological responses has been discussed.