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81.
Mahesh Chandra Alok Kalra Pradeep K. Sharma Rajender S. Sangwan 《Journal of industrial microbiology & biotechnology》2009,36(4):605-609
Capabilities of cellulase production, using delignified bioprocessings of medicinal and aromatic plants, viz. citronella (Cymbopogon winterianus) and Artemisia annua (known as marc of Artemisia) and garden waste (chiefly containing Cynodon dactylon), by the six species of Trichoderma were comparatively evaluated. Among the members of Trichoderma studied, T. citrinoviride was found to be the most efficient producer of cellulases along with a high level of β- glucosidase (produced 102.4 IU g−1 on marc of Artemisia; 101.33 IU g−1 on garden waste; 81.86 IU g−1 on distillation waste of citronella and 94.77 IU g−1 on pure cellulose). Although T. virens was noticed to be the minimal enzyme producer fungus, it interestingly could not produce complete cellulase enzyme complex
on any test waste or pure cellulose, except on marc of Artemisia, where it produced all three enzymes of the complex. Immediate reduction in pH was also noticed during fermentation in the
case of pure polymer (cellulose) by all tested fungi, while it was delayed with delignified agrowastes. The pH profile varied
with the substrate used as well as with individual species of Trichoderma. On the other hand, no alteration in pH with any species of Trichoderma was noticed when grown on marc of A. annua, which might be due to the buffering capacity of this marc. 相似文献
82.
ER stress-regulated translation increases tolerance to extreme hypoxia and promotes tumor growth 总被引:1,自引:0,他引:1
Bi M Naczki C Koritzinsky M Fels D Blais J Hu N Harding H Novoa I Varia M Raleigh J Scheuner D Kaufman RJ Bell J Ron D Wouters BG Koumenis C 《The EMBO journal》2005,24(19):3470-3481
Tumor cell adaptation to hypoxic stress is an important determinant of malignant progression. While much emphasis has been placed on the role of HIF-1 in this context, the role of additional mechanisms has not been adequately explored. Here we demonstrate that cells cultured under hypoxic/anoxic conditions and transformed cells in hypoxic areas of tumors activate a translational control program known as the integrated stress response (ISR), which adapts cells to endoplasmic reticulum (ER) stress. Inactivation of ISR signaling by mutations in the ER kinase PERK and the translation initiation factor eIF2alpha or by a dominant-negative PERK impairs cell survival under extreme hypoxia. Tumors derived from these mutant cell lines are smaller and exhibit higher levels of apoptosis in hypoxic areas compared to tumors with an intact ISR. Moreover, expression of the ISR targets ATF4 and CHOP was noted in hypoxic areas of human tumor biopsy samples. Collectively, these findings demonstrate that activation of the ISR is required for tumor cell adaptation to hypoxia, and suggest that this pathway is an attractive target for antitumor modalities. 相似文献
83.
Information on the use of buffalo follicular fluid (buFF) in modulation of ovarian functions in farm animals is scanty compared to other species. This is an attempt to investigate the effect of direct administration and active immunization of 30 kDa and above buFF proteins on ovarian functions in goats. Treatment of goats (n = 6) with steroid free 30 kDa and above buFF protein fraction during late-luteal phase for 4 days (days 12 or 13 to days 15 or 16) of the natural cycle, delayed the onset of estrus by 24 h compared to control although the mean duration of estrus was unaffected. A 71% increase (P = 0.06) in mean ovulation number was also observed following treatment. However, the population of large (> or =5 mm diameter) follicle was not affected. The ovarian activity calculated as total of ovulation and large follicles increased (1.6 times) significantly (P = 0.02) in treated animals. Active immunization of goats (n = 5) against these proteins did not affect the onset and duration of estrus. Similarly, the ovulation rate, number of large follicles and the ovarian activity did not differ significantly between immunized and control groups. The study revealed that 30 kDa and above buffalo follicular fluid contains some factor(s) that cause delay in the onset of estrus in goats and increase the ovulation rate. Active immunization against these proteins in goat did not show any effect either on onset, duration of estrus or ovulation rate and large follicle population. Detailed study on these buffalo follicular fluid proteins may help to use them further for modulation of ovarian function in farm animals. 相似文献
84.
Chintamani Jai Parakash Singh Mahesh K Mittal Sunita Saxena Anju Bansal Ashima Bhatia Pranjal Kulshreshtha 《World journal of surgical oncology》2005,3(1):1-9
Background
Lung cancer still remains one of the most commonly occurring solid tumors and even in stage Ia, surgery fails in 30% of patients who develop distant metastases. It is hypothesized that these must have developed from occult circulating tumor cells present at the time of surgery, or before. The aim of the present study was to detect such cells in the peripheral blood and to monitor these cells following surgery.Methods
30 patients treated for lung cancer with surgery were monitored for circulating epithelial cells (CEC) by taking peripheral blood samples before, 2 weeks and 5 months after surgery and/or radiotherapy (RT) chemotherapy (CT) or combined RT/CT using magnetic bead enrichment and laser scanning cytometry (MAINTRAC®) for quantification of these cells.Results
In 86% of the patients CEC were detected before surgery and in 100% at 2 weeks and 5 months after surgery. In the control group, which consisted of 100 normal donors without cancer, 97 % were negative for CEC. A significantly higher number of CEC was found preoperatively in patients with squamous cell carcinoma than in those with adenocarcinoma. In correlation to the extent of parenchymal manipulation 2 weeks after surgery, an increase in numbers of CEC was observed with limited resections (18/21) whereas pneumonectomy led to a decrease (5/8) of CEC, 2 weeks after surgery. The third analysis done 5 months after surgery identified 3 groups of patients. In the group of 5 patients who received neo- or adjuvant chemo/radiotherapy there was evidence that monitoring of CEC can evaluate the effects of therapy. Another group of 7 patients who underwent surgery only showed a decrease of CEC and no signs of relapse. A third group of 11 patients who had surgery only, showed an increase of CEC (4 with an initial decrease after surgery and 7 with continuous increase). In the group with a continuous increase during the following 24 months, 2 early relapses in patients with stage Ia adenocarcinoma were observed. The increase of CEC preceded clinical detection by six months.Conclusion
We consider, therefore, that patients with adenocarcinoma and a continuous increase of CEC after complete resection for lung cancer are at an increased risk of early relapse. 相似文献85.
Ananth M 《Acta biotheoretica》2005,53(3):217-239
This paper defends the position that the supposed gap between biological altruism and psychological altruism is not nearly
as wide as some scholars (e.g., Elliott Sober) insist. Crucial to this defense is the use of James Mark Baldwin's concepts
of “organic selection”and “social heredity” to assist in revealing that the gap between biological and psychological altruism
is more of a small lacuna. Specifically, this paper argues that ontogenetic behavioral adjustments, which are crucial to individual
survival and reproduction, are also crucial to species survival. In particular, it is argued that human psychological altruism
is produced and maintained by various sorts of mimicry and self-reflection in the aid of both individual and species survival.
The upshot of this analysis is that it is possible to offer an account of psychological altruism that is closelytethered to
biological altruism without reducing entirely the former to thelatter. 相似文献
86.
87.
Advances in genomics and proteomics have opened up new possibilities for the rapid functional assignment and global characterization of proteins. Large-scale studies have accelerated this effort by using tools and strategies that enable highly parallel analysis of huge repertoires of biomolecules. Organized assortments of molecules on arrays have furnished a robust platform for rapid screening, lead discovery and molecular characterization. The essential advantage of microarray technology is attributed to the massive throughput attainable, coupled with a highly miniaturized platform--potentially driving discovery both as an analytical and diagnostic tool. The scope of microarrays has in recent years expanded impressively. Virtually every biological component--from diverse small molecules and macromolecules (such as DNA and proteins) to entire living cells--has been harnessed on microarrays in attempts to dissect the bewildering complexity of life. Herein we highlight strategies that address challenges in proteomics using microarrays of immobilized proteins and small molecules. Of specific interest are the techniques involved in stably immobilizing proteins and chemical libraries on slide surfaces as well as novel strategies developed to profile activities of proteins on arrays. As a rapidly maturing technology, microarrays pave the way forward in high-throughput proteomic exploration. 相似文献
88.
Mahesh Khatri Varun Dwivedi Steven Krakowka Cordelia Manickam Ahmed Ali Leyi Wang Zhuoming Qin Gourapura J. Renukaradhya Chang-Won Lee 《Journal of virology》2010,84(21):11210-11218
Pigs are capable of generating reassortant influenza viruses of pandemic potential, as both the avian and mammalian influenza viruses can infect pig epithelial cells in the respiratory tract. The source of the current influenza pandemic is H1N1 influenza A virus, possibly of swine origin. This study was conducted to understand better the pathogenesis of H1N1 influenza virus and associated host mucosal immune responses during acute infection in humans. Therefore, we chose a H1N1 swine influenza virus, Sw/OH/24366/07 (SwIV), which has a history of transmission to humans. Clinically, inoculated pigs had nasal discharge and fever and shed virus through nasal secretions. Like pandemic H1N1, SwIV also replicated extensively in both the upper and lower respiratory tracts, and lung lesions were typical of H1N1 infection. We detected innate, proinflammatory, Th1, Th2, and Th3 cytokines, as well as SwIV-specific IgA antibody in lungs of the virus-inoculated pigs. Production of IFN-γ by lymphocytes of the tracheobronchial lymph nodes was also detected. Higher frequencies of cytotoxic T lymphocytes, γδ T cells, dendritic cells, activated T cells, and CD4+ and CD8+ T cells were detected in SwIV-infected pig lungs. Concomitantly, higher frequencies of the immunosuppressive T regulatory cells were also detected in the virus-infected pig lungs. The findings of this study have relevance to pathogenesis of the pandemic H1N1 influenza virus in humans; thus, pigs may serve as a useful animal model to design and test effective mucosal vaccines and therapeutics against influenza virus.Swine influenza is a highly contagious, acute respiratory viral disease of swine. The causative agent, swine influenza virus (SwIV), is a strain of influenza virus A in the Orthomyxoviridae family. Clinical disease in pigs is characterized by sudden onset of anorexia, weight loss, dyspnea, pyrexia, cough, fever, and nasal discharge (21). Porcine respiratory tract epithelial cells express sialic acid receptors utilized by both avian (α-2,3 SA-galactose) and mammalian (α-2,6 SA-galactose) influenza viruses. Thus, pigs can serve as “mixing vessels” for the generation of new reassortant strains of influenza A virus that may contain RNA elements of both mammalian and avian viruses. These “newly generated” and reassorted viruses may have the potential to cause pandemics in humans and enzootics in animals (52).Occasional transmission of SwIV to humans has been reported (34, 43, 52), and a few of these cases resulted in human deaths. In April 2009, a previously undescribed H1N1 influenza virus was isolated from humans in Mexico. This virus has spread efficiently among humans and resulted in the current human influenza pandemic. Pandemic H1N1 virus is a triple reassortant (TR) virus of swine origin that contains gene segments from swine, human, and avian influenza viruses. Considering the pandemic potential of swine H1N1 viruses, it is important to understand the pathogenesis and mucosal immune responses of these viruses in their natural host. Swine can serve as an excellent animal model for the influenza virus pathogenesis studies. The clinical manifestations and pathogenesis of influenza in pigs closely resemble those observed in humans. Like humans, pigs are also outbred species, and they are physiologically, anatomically, and immunologically similar to humans (9, 23, 39, 40). In contrast to the mouse lung, the porcine lung has marked similarities to its human counterpart in terms of its tracheobronchial tree structure, lung physiology, airway morphology, abundance of airway submucosal glands, and patterns of glycoprotein synthesis (8, 10, 17). Furthermore, the cytokine responses in bronchoalveolar lavage (BAL) fluid from SwIV-infected pigs are also identical to those observed for nasal lavage fluids of experimentally infected humans (20). These observations support the idea that the pig can serve as an excellent animal model to study the pathogenesis of influenza virus.Swine influenza virus causes an acute respiratory tract infection. Virus replicates extensively in epithelial cells of the bronchi and alveoli for 5 to 6 days followed by clearance of viremia by 1 week postinfection (48). During the acute phase of the disease, cytokines such as alpha interferon (IFN-α), tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-1), IL-6, IL-12, and gamma interferon (IFN-γ) are produced. These immune responses mediate both the clinical signs and pulmonary lesions (2). In acute SwIV-infected pigs, a positive correlation between cytokines in BAL fluid, lung viral titers, inflammatory cell infiltrates, and clinical signs has been detected (2, 48).Infection of pigs with SwIV of one subtype may confer complete protection from subsequent infections by homologous viruses and also partial protection against heterologous subtypes, but the nature of the immune responses generated in the swine are not fully delineated. Importantly, knowledge related to host mucosal immune responses in the SwIV-infected pigs is limited. So far only the protective virus-specific IgA and IgG responses in nasal washes and BAL fluid, as well as IgA, IgG, and IgM responses in the sera of infected pigs, have been reported (28). Pigs infected with H3N2 and H1N1 viruses have an increased frequency of neutrophils, NK cells, and CD4 and CD8 T cells in the BAL fluid (21). Pigs infected with the pandemic H1N1 virus showed activated CD4 and CD8 T cells in the peripheral blood on postinfection day (PID) 6 (27). Proliferating lymphocytes in BAL fluid and blood and virus-specific IFN-γ-secreting cells in the tracheobronchial lymph nodes (TBLN) and spleen were detected in SwIV-infected pigs (7). Limited information is available on the mucosal immune responses in pig lungs infected with SwIV, which has a history of transmission to humans.In this study, we examined the acute infection of SwIV (strain SwIV OH07) in pigs with respect to viral replication, pathology, and innate and adaptive immune responses in the respiratory tract of these pigs. This virus was isolated from pigs which suffered from respiratory disease in Ohio, and the same virus was also transmitted to humans and caused clinical disease (43, 55). Interestingly, like pandemic H1N1 influenza virus, SwIV also infects the lower respiratory tract of pigs. Delineation of detailed mucosal immune responses generated in pig lungs during acute SwIV OH07 infection may provide new insights for the development of therapeutic strategies for better control of virus-induced inflammation and for the design and testing of effective vaccines. 相似文献
89.
Pillai JB Gupta M Rajamohan SB Lang R Raman J Gupta MP 《American journal of physiology. Heart and circulatory physiology》2006,291(4):H1545-H1553
Poly(ADP-ribose) polymerase-1 (PARP), a chromatin-bound enzyme, is activated by cell oxidative stress. Because oxidative stress is also considered a main component of angiotensin II-mediated cell signaling, it was postulated that PARP could be a downstream target of angiotensin II-induced signaling leading to cardiac hypertrophy. To determine a role of PARP in angiotensin II-induced hypertrophy, we infused angiotensin II into wild-type (PARP(+/+)) and PARP-deficient mice. Angiotensin II infusion significantly increased heart weight-to-tibia length ratio, myocyte cross-sectional area, and interstitial fibrosis in PARP(+/+) but not in PARP(-/-) mice. To confirm these results, we analyzed the effect of angiotensin II in primary cultures of cardiomyocytes. When compared with PARP(-/-) cardiomyocytes, angiotensin II (1 microM) treatment significantly increased protein synthesis in PARP(+/+) myocytes, as measured by (3)H-leucine incorporation into total cell protein. Angiotensin II-mediated hypertrophy of myocytes was accompanied with increased poly-ADP-ribosylation of nuclear proteins and depletion of cellular NAD content. When cells were treated with cell death-inducing doses of angiotensin II (10-20 microM), robust myocyte cell death was observed in PARP(+/+) but not in PARP(-/-) myocytes. This type of cell death was blocked by repletion of cellular NAD levels as well as by activation of the longevity factor Sir2alpha deacetylase, indicating that PARP induction and subsequent depletion of NAD levels are the sequence of events causing angiotensin II-mediated cardiomyocyte cell death. In conclusion, these results demonstrate that PARP is a nuclear integrator of angiotensin II-mediated cell signaling contributing to cardiac hypertrophy and suggest that this could be a novel therapeutic target for the management of heart failure. 相似文献
90.
An aerobic microorganism with an ability to utilize phenol as carbon and energy source was isolated from a hydrocarbon contamination
site by employing selective enrichment culture technique. The isolate was identified as Arthrobacter citreus based on morphological, physiological and biochemical tests. This mesophilic organism showed optimal growth at 25°C and at
pH of 7.0. The phenol utilization studies with Arthrobacter citreus showed that the complete assimilation occurred in 24 hours. The organism metabolized phenol up to 22 mM concentrations whereas
higher levels were inhibitory. Thin layer chromatography, UV spectral and enzyme analysis were suggestive of catechol, as
a key intermediate of phenol metabolism. The enzyme activities of phenol hydroxylase and catechol 2,3-dioxygenase in cell
free extracts of Arthrobacter citreus were indicative of operation of a meta-cleavage pathway for phenol degradation. The organism had additional ability to degrade catechol, cresols and naphthol. The
degradation rates of phenol by alginate and agar immobilized cells in batch fermentations showed continuous phenol metabolism
for a period of eight days. 相似文献