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121.

Background

Prodigiosin produced by Serratia marcescens is a promising drug owing to its reported characteristics of having antifungal, immunosuppressive and antiproliferative activity. From an industrial point of view the necessity to obtain a suitable medium to simultaneously enhance the growth of Serratia marcescens and the pigment production was the aim of this work. The usage of individual fatty acid as substrate in industries would be cost-effective in the long run and this paved the way for us to try the effect of different fatty acid-containing seeds and oils of peanut, sesame and coconut as source of substrate.

Results

The addition of sugars only showed slight enhancement of prodigiosin production in nutrient broth but not in fatty acid containing seed medium. The powdered peanut broth had supported better growth of Serratia marcescens and higher yield of prodigiosin when compared with the existing nutrient broth and peptone glycerol broth. A block in prodigiosin production was seen above 30°C in nutrient broth, but the fatty acid seed medium used by us supported prodigiosin production upto 42°C though the yields were lower than what was obtained at 28°C. From the results, the fatty acid form of carbon source has a role to play in enhanced cell growth and prodigiosin production.

Conclusion

We conclude by reporting that the powdered and sieved peanut seed of different quality grades were consistent in yielding a fourty fold increase in prodigiosin production over the existing media. A literature survey on the composition of the different media components in nutrient broth, peptone glycerol broth and the fatty acid containing seeds and oils enabled us to propose that the saturated form of fatty acid has a role to play in enhanced cell growth and prodigiosin production. This work has also enabled us to report that the temperature related block of prodigiosin biosynthesis varies with different media and the powdered peanut broth supports prodigiosin production at higher temperatures. The medium suggested in this work is best suitable from an industrial point of view in being economically feasible, in terms of the higher prodigiosin yield and the extraction of prodigiosin described in this paper is simple with minimal wastage.
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122.
In the present study, we report the distribution of true to type and atypical Nili-Ravi buffalo, a vulnerable dairy type riverine breed of North India and its underlying genetic structure. Out of total investigated buffaloes 73.5% had bilateral wall eyes while 5.4% had unilateral wall eyes and 21.1% had no wall eyes. 41.15% of Nili-Ravi buffaloes maintained in the breeding farm were having typical true to the type characteristics (both eyes walled, white markings in forehead, muzzle/chin, all the four legs and tail) while only 28.5% of Nili-Ravi buffaloes were true to the type under field conditions. Genotypic data were generated in four groups of Nili-Ravi buffalo (FMTNR—Typical Nili-Ravi from farm; FMANR—Atypical Nili-Ravi from farm; FDTNR—Typical Nili-Ravi from field; FDANR—Atypical Nili-Ravi from field) at 16 microsatellite loci. Comparative genetic analysis of various groups of Nili-Ravi buffaloes with Murrah revealed significant between group differences with an estimated global F ST of 0.063. Pair-wise F ST values ranged from 0.003 (between FDTNR and FDANR) to 0.112 (between FMTNR and FDTNR). Phylogenetic analysis and multi-dimensional scaling revealed clustering of FDTNR and FDANR together while FMTNR and FMANR clustered separately with Murrah in between farm and field Nili-Ravi buffaloes. Based on the results, the paper also proposes three pronged strategy for conservation and sustainable genetic improvement of Nili-Ravi buffalo in India.  相似文献   
123.
All-trans-canthaxanthin (4, 4′-diketo β-carotene) but not 9-cis-canthaxanthin has been shown to induce apoptosis in some cell lines. In this study apoptotic activity of 9-cis-canthaxanthin on THP-1 macrophage is reported. Comparison of apoptotic activities of the two canthaxanthin isomers on this cell line by annexin V-cy3 and TUNEL assays indicated the higher pro-apoptotic activity of 9-cis-isomer than the all-trans-isomer. Canthaxanthin-induced apoptosis in this cell line was found to be accompanied by increased caspase-3 and caspase-8 activities, indicating its progression via caspase cascade. Induction of both caspase activities was higher by 9-cis-canthaxanthin than that by trans-canthaxanthin. All these results suggest that canthaxanthin stereoisomers differentially induce apoptosis of THP-1 monocyte/macrophage.  相似文献   
124.
Nandini  S.  Sarma  S. S. S. 《Aquatic Ecology》2021,55(4):1305-1316

We tested the effect of different food (Chlorella vulgaris) concentrations on the population growth and demographic variables of Dipleuchlanis propatula. In addition, we also tested the effect of competition from two other zooplankton species (a rotifer Plationus patulus and a ciliate Paramecium sp.). The parthenogenetic eggs of D. propatula carry a gelatinous matrix with a thickness of about 20 µm. Population growth of D. propatula increased with increase in the algal density. Depending on the food availability, the peak abundances of D. propatula varied from 9 to 50 ind. ml?1. The rate of population increase, r, varied from 0.18 to 0.23 per day. Food density had a significant effect (p?<?0.05, Tukey test) on this variable too. In spite of higher peak densities observed at high food levels, the r values were not very different; this was due to the long lag phase before the population increased. Dipleuchlanis propatula growth was lower due to competition from ciliates. Food density had no significant effect on the average life span, which varied from 5 to 7 days. However, both gross and net reproductive rates increased with increase in algal food. These results show that D. propatula had growth patterns similar to other members of the family Euchlanidae.

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125.

Background  

Studies on amphibian limb regeneration began in the early 1700's but we still do not completely understand the cellular and molecular events of this unique process. Understanding a complex biological process such as limb regeneration is more complicated than the knowledge of the individual genes or proteins involved. Here we followed a systems biology approach in an effort to construct the networks and pathways of protein interactions involved in formation of the accumulation blastema in regenerating axolotl limbs.  相似文献   
126.
The herpesviruses, like most other DNA viruses, replicate in the host cell nucleus. Subnuclear domains known as promyelocytic leukemia protein nuclear bodies (PML-NBs), or ND10 bodies, have been implicated in restricting early herpesviral gene expression. These viruses have evolved countermeasures to disperse PML-NBs, as shown in cells infected in vitro, but information about the fate of PML-NBs and their functions in herpesvirus infected cells in vivo is limited. Varicella-zoster virus (VZV) is an alphaherpesvirus with tropism for skin, lymphocytes and sensory ganglia, where it establishes latency. Here, we identify large PML-NBs that sequester newly assembled nucleocapsids (NC) in neurons and satellite cells of human dorsal root ganglia (DRG) and skin cells infected with VZV in vivo. Quantitative immuno-electron microscopy revealed that these distinctive nuclear bodies consisted of PML fibers forming spherical cages that enclosed mature and immature VZV NCs. Of six PML isoforms, only PML IV promoted the sequestration of NCs. PML IV significantly inhibited viral infection and interacted with the ORF23 capsid surface protein, which was identified as a target for PML-mediated NC sequestration. The unique PML IV C-terminal domain was required for both capsid entrapment and antiviral activity. Similar large PML-NBs, termed clastosomes, sequester aberrant polyglutamine (polyQ) proteins, such as Huntingtin (Htt), in several neurodegenerative disorders. We found that PML IV cages co-sequester HttQ72 and ORF23 protein in VZV infected cells. Our data show that PML cages contribute to the intrinsic antiviral defense by sensing and entrapping VZV nucleocapsids, thereby preventing their nuclear egress and inhibiting formation of infectious virus particles. The efficient sequestration of virion capsids in PML cages appears to be the outcome of a basic cytoprotective function of this distinctive category of PML-NBs in sensing and safely containing nuclear aggregates of aberrant proteins.  相似文献   
127.
In many renal diseases, transforming growth factor β (TGFβ)-stimulated canonical Smad 3 and noncanonical mechanistic target of rapamycin (mTOR) promote increased protein synthesis and mesangial cell hypertrophy. The cellular underpinnings involving these signaling molecules to regulate mesangial cell hypertrophy are not fully understood. Deptor has recently been identified as an mTOR interacting protein and functions as an endogenous inhibitor of the kinase activity for both TORC1 and TORC2. Prolonged incubation of mesangial cells with TGFβ reduced the levels of deptor concomitant with an increase in TORC1 and TORC2 activity. Sustained TGFβ activation was required to inhibit association of deptor with mTOR, whereas rapid activation had no effect. Using the mTOR inhibitor PP242, we found that TGFβ-induced both early and sustained activation of TORC1 and TORC2 was necessary for deptor suppression. PP242-induced reversal of deptor suppression by TGFβ was associated with a significant inhibition of TGFβ-stimulated protein synthesis and hypertrophy. Interestingly, expression of siRNA against Smad 3 or Smad 7, which blocks TGFβ receptor-specific Smad 3 signaling, prevented TGFβ-induced suppression of deptor abundance and TORC1/2 activities. Furthermore, overexpression of Smad 3 decreased deptor expression similar to TGFβ stimulation concomitant with increased TORC1 and TORC2 activities. Finally, knockdown of deptor reversed Smad 7-mediated inhibition of protein synthesis and mesangial cell hypertrophy induced by TGFβ. These data reveal the requirement of both early and late activation of mTOR for TGFβ-induced protein synthesis. Our results support that TGFβ-stimulated Smad 3 acts as a key node to instill a feedback loop between deptor down-regulation and TORC1/2 activation in driving mesangial cell hypertrophy.  相似文献   
128.
Field experiments were conducted to determine the effects of exclusion of UV-A/B and UV-B alone on growth parameters, activity of antioxidant enzymes, level of antioxidants and yield, to evaluate the intra-specific variations in sensitivity of these responses in eight soybean (Glycine max) varieties (PK-472, PK-1029, Pusa-24, JS-7105, JS-335, Hardee, NRC-7 and Kalitur). The plants were grown in specially designed UV-exclusion chambers which lined with selective UV filters to exclude either UV-B (<320 nm) or UV-A/B (<400 nm). Plants grown under UV-exclusion filters were compared with those grown under polythene filter which transmitted ambient UV-B and UV-A radiation. The results indicate that the exclusion of solar UV-B and UV-A/B enhanced the vegetative growth (plant height and leaf area), total biomass accumulation and yield (number of seeds and seed weight) of all the varieties as compared with those grown under ambient UV. The activities of SOD, GPX, APX and GR, and levels of ASA were significantly decreased, while α-tocopherol increased after the exclusion of UV-B and UV-A/B in all varieties. These results suggest that the ambient level of UV-B and UV-A radiation evoked some active oxygen species to accumulate, which in turn retarded the growth, development and yield of soybean varieties. On the basis of biomass, UV-B (280–315 nm) sensitivity can be arranged in decreasing order as PK-472 > Hardee > JS-335 > Kalitur > JS 71-05 > Pusa-24 > NRC-7 > PK-1029 and UV-A/B sensitivity can be arranged in decreasing order as PK-472 > Kalitur > JS-335 > Hardee > Pusa-24 > JS 71-05 > NRC-7 > PK-1029. The results indicate var. PK-472 is more sensitive than other varieties and PK-1029 is least sensitive to ambient level of UV radiation. This study in the area of UV-B and UV-A/B stress provides an extensive data that can be used as a predictive basis in crop sciences to further investigate some of the tolerant varieties in field studies.  相似文献   
129.
Neuroblastoma is an aggressive childhood disease of the sympathetic nervous system. Treatments are often ineffective and have serious side effects. Conventional therapy of neuroblastoma includes the differentiation agents. Unlike chemo-radiotherapy, differentiation therapy shows minimal side effects on normal cells, because normal non-malignant cells are already differentiated. Keeping in view the limited toxicity of Withania somnifera (Ashwagandha), the current study was aimed to investigate the efficacy of Ashwagandha water extract (ASH-WEX) for anti-proliferative potential in neuroblastoma and its underlying signalling mechanisms. ASH-WEX significantly reduced cell proliferation and induced cell differentiation as indicated by morphological changes and NF200 expression in human IMR-32 neuroblastoma cells. The induction of differentiation was accompanied by HSP70 and mortalin induction as well as pancytoplasmic translocation of the mortalin in ASH-WEX treated cells. Furthermore, the ASH-WEX treatment lead to induction of neural cell adhesion molecule (NCAM) expression and reduction in its polysialylation, thus elucidating its anti-migratory potential, which was also supported by downregulation of MMP 2 and 9 activity. ASH-WEX treatment led to cell cycle arrest at G0/G1 phase and increase in early apoptotic population. Modulation of cell cycle marker Cyclin D1, anti-apoptotic marker bcl-xl and Akt-P provide evidence that ASH-WEX may prove to be a promising phytotherapeutic intervention in neuroblatoma related malignancies.  相似文献   
130.
Physiology and Molecular Biology of Plants - The experiments were conducted for the estimation of the mitigating effect of the static magnetic field (SMF&nbsp;of 200?mT for 1?h)...  相似文献   
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