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131.
Sathesh kanna Velli Jagan Sundaram Manikandan Murugan Gopalakrishnan Balaraman Devaki Thiruvengadam 《Journal of biochemical and molecular toxicology》2019,33(10)
Vanillic acid (VA) is found in high concentrations in various plants and used as traditional medicine for various diseases. The aim of the existing study is to illustrate the protective effects of VA against benzo(a)pyrene (B(a)P)‐induced lung cancer in Swiss albino mice. B(a)P (50 mg/kg b.wt.) was given orally to induce lung cancer in mice. The body weight, tumor incidence, carcinoembryonic antigen (CEA), neuron‐specific enolase (NSE), and enzymatic/nonenzymatic antioxidants (superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, and glutathione) were estimated. Further histochemical investigation through hematoxylin and eosin staining was also carried out. B(a)P administered groups showed increased levels of serum pathological markers CEA, NSE along with reduced final body weight as well as decreased tissue enzymatic and nonenzymatic antioxidants activities, whereas VA treatment (200mg/kg/b.wt) along with B(a)P showed significantly reverted the above changes, which proves as prominent anticancer effects in experimentally induced lung cancer. Overall, these results suggest that VA has an efficient preventive action against B(a)P‐induced lung cancer, and this is attributed to its free‐radical scavenging antioxidant activities. 相似文献
132.
Rajasekar A Babu TG Pandian ST Maruthamuthu S Palaniswamy N Rajendran A 《Journal of industrial microbiology & biotechnology》2007,34(9):589-598
A facultative anaerobic species Serratia marcescens ACE2 isolated from the corrosion products of diesel transporting pipeline in North West, India was identified by 16S rDNA
sequence analysis. The role of Serratia marcesens ACE2 on biodegradation of diesel and its influence on the corrosion of API 5LX steel has been elucidated. The degrading strain
ACE2 is involved in the process of corrosion of steel API 5LX and also utilizes the diesel as an organic source. The quantitative
biodegradation efficiency (BE) of diesel was 58%, calculated by gas-chromatography–mass spectrum analysis. On the basis of
gas-chromatography–mass spectrum (GC–MS), Fourier Transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD), the
involvement of Serratia marcescens on degradation and corrosion has been investigated. This basic study will be useful for the development of new approaches
for detection, monitoring and control of microbial corrosion. 相似文献
133.
The aim of the present investigation was to evaluate the anti-diabetic activity of 20-OH-ecdysone on glucose metabolic key enzymes in control and streptozotocin induced diabetic rats. On oral administration of 20-OH-ecdysone at a dose of 5mg/kg body weight per day to diabetic rats for 30 days resulted in a significant decrease in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and an increase in the levels of insulin and hemoglobin. Administration of 20-OH-ecdysone showed significant increase in the levels of glycolytic enzyme (hexokinase) and hepatic shunt enzyme (glucose-6-phosphate dehydrogenase) whereas significant decrease in the levels of gluconeogenic enzymes (glucose-6-phosphatase and fructose-1,6-bisphosphatase) in diabetic treated rats. Furthermore, protection against body weight loss of diabetic animals also observed. This study indicates that the administration of 20-OH-ecdysone to diabetic rats resulted in alterations in the metabolism of glucose with subsequent reduction in plasma glucose levels. A comparison was made between the action of 20-OH-ecdysone and antidiabetic drug-glibenclamide. The effects produced by the 20-OH-ecdysone were comparable to that of glibenclamide. 相似文献
134.
Gliomas remain to be an unresolved medical problem. Better understanding of complex regulation and key molecules involved
in glioma pathology are needed for designing new and effective treatment modalities. Activation of mitogen-activated protein
kinase/extracellular signal regulated kinase (ERK) pathway is known to be having a critical role in cell proliferation and
differentiation during the invasion and metastasis of the tumor cells. In the present study, N-ethyl N-nitrosourea induced
glioma rat model was used to understand the role of ERK1/2 and Akt pathways in the progression of tumor malignancy. Twenty-four
glioma rat brains of early (P90) and progressive (P180) stages were used for histological and immunoblot analysis. Results
have shown increased levels of activated ERK1/2, activated Akt or protein kinase B, Bcl-2 and pBad in the glioma rats. This
study may indicate increased cell proliferation and angiogenesis, mediated through activation of both ERK and Akt pathways
along with increased levels of pBad. Further, pAkt and Bcl-2 levels in the progressive stage glioma rats may indicate existence
of sustained tumor cell survival signals. Moreover, enhanced pBad levels in tumor may indicate that there are anti-apoptotic
mechanisms, further making the malignant cells resistant to apoptosis. 相似文献
135.
Deslorelin, a luteinizing hormone releasing hormone (LHRH) agonist, is transported via the LHRH-receptor (LHRH-R) and exhibits regional variation as follows: inferior turbinate posterior (ITP)>medium turbinate posterior (MTP)>medium turbinate anterior (MTA) of the bovine nasal mucosa. Differential LHRH-R expression in various regions of the nose is a potential explanation for regional variation in deslorelin transport. Thus, the objective was to determine whether LHRH-R expression exhibits regional variation in bovine nasal mucosa. LHRH-R density (B(max)) and affinity constant (K(d)) were determined by saturation experiments using 0.5mg tissue in the presence of increasing amounts of I(125)-deslorelin (100-100,000 cpm) at 4 degrees C for 4h. The 50% inhibitory concentration (IC(50)) was determined by competition experiments using various amounts of unlabelled deslorelin (0.01-3000 ng) at 4 degrees C for 4h. LHRH-R mRNA and protein expressions were determined using real-time PCR and Western blot analysis, respectively. LHRH-R B(max) and K(d) varied between the regions of excised bovine nasal mucosa: ITP>MTP>MTA. The inhibition experiments yielded two IC(50) concentrations which exhibited trends similar to B(max) and K(d). Real-time PCR and Western blot analysis indicated that LHRH-R expression exhibits similar trends: ITP>MTP>MTA. We identified two deslorelin binding sites in the nasal tissues, with high affinity sites representing approximately 60-70% of the total sites available. In summary, regional differences in nasal deslorelin transport correlate with regional differences in LHRH-R expression, with LHRH-R expression, peptide binding, and transport being the highest in the inferior turbinate posterior region of the nose. 相似文献
136.
The Methylobacterium sp. strain NPFM-SB3, isolated from Sesbania rostrata stem nodules possessed nitrogenase activity and nodA genes. Pure culture of NPFM-SB3 strain produced indole-3-acetic acid, cytokinins and on inoculation to rice plants resulted in numerous lateral roots. Inoculation of synthetic auxins 2,4-dichlorophenoxy acetic acid, naphthalene acetic acid or flavonoids naringenin and dihydroxy-4-methoxyisoflavone individually or to bacterial inoculated rice seedlings improved the plant growth and lateral root formation under hydroponic condition. The formation of nodule-like structure and nitrogenase activity which is purely auxin dependent was observed in 2,4-dichlorophenoxy acetic acid treatments to Methylobacterium sp. NPFM-SB3 inoculated rice plants. The rhizobia entered through fissures formed due to lateral root emergence and spread intercellularly in the nodular structures concluded that the effect of 2,4-dichlorophenoxy acetic acid treatment for rice seedlings grown under gnotobiotic conditions is to create a niche in which these bacteria can grow. 相似文献
137.
Raman M. Sundaram M. R. Vishnupriya Gouri S. Laha N. Shobha Rani P. Srinivasa Rao Sena M. Balachandran Gajjala Ashok Reddy Nukala P. Sarma Ramesh V. Sonti Dr. 《Biotechnology journal》2009,4(3):400-407
Bacterial blight (BB) is a serious disease of rice in India. We have used molecular marker-assisted selection in a backcross breeding program to introgress three genes (Xa21, xa13, and xa5) for BB resistance into Triguna, a mid-early duration, high yielding rice variety that is susceptible to BB. At each generation in the backcross program, molecular markers were used to select plants possessing these resistance genes and to select plants that have maximum contribution from the Triguna genome. A selected BC3F1 plant was selfed to generate homozygous BC3F2 plants with different combinations of BB resistance genes. Plants containing the two-gene combination, Xa21 and xa13, were found to exhibit excellent resistance against BB. Single plant selections for superior agronomic characteristics were performed on the progeny of these plants, from BC3F3 generation onwards. The selected plants were subjected to yield trials at the BC3F8 generation and were found to have a significant yield advantage over Triguna. The newly developed lines are being entered into national multi-location field trials. This work represents a successful example of the application of molecular marker-assisted selection for BB resistance breeding in rice. 相似文献
138.
K. Sakthivel N. Shobha Rani Manish K. Pandey A. K. P. Sivaranjani C. N. Neeraja S. M. Balachandran M. Sheshu Madhav B. C. Viraktamath G. S. V. Prasad R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2009,24(2):185-190
Fragrance development in rice has been reported due to a 8-bp deletion in the exon 7 of badh2 gene located on Chromosome 8S. Multiplex markers targeting the functional InDel polymorphism was earlier reported for genotyping
fragrance trait, but the marker was observed to be inconsistent and difficult to use. We have developed a simple, co-dominant,
functional marker for fragrance trait, which can be resolved in an agarose gel and validated in Basmati and non-Basmati aromatic
rice varieties and in a mapping population segregated for fragrance trait. The marker targets the InDel polymorphism in badh2 gene and amplifies 95 and 103 bp fragments in fragrant and non-fragrant genotypes, respectively. The newly developed marker
was highly efficient in discriminating all fragrant and non-fragrant genotypes and showed perfect co-segregation with the
trait of fragrance in the mapping population. We recommend the use of this simple, low-cost marker in routine genotyping for
fragrance trait in large scale breeding materials and germplasm. 相似文献
139.
The ability to incorporate non-canonical amino acids into proteins by genetic or chemical methods allows one to introduce
novel chemical properties into a protein at a defined residue. Such a residue may then be modified using common organic transformations.
In this way, the structure or function of the peptide may be altered without perturbing any of the other neighbouring amino
acids in the peptide chain. Here, we describe the syntheses and potential applications of multiple para-substituted phenylalanine derivatives comprising an isothiocyanate, α-diazoketone, or nitrone functionality. In all, three
novel amino acids were synthesized in good overall yields. These non-canonical amino acids permit the further development
of in vitro and in vivo chemoselective and regioselective bioconjugate reactions not possible with other reagents. 相似文献
140.
Ajay Kumar Chaudhary Mamta Singh Alok C Bharti Kamlesh Asotra Shanthy Sundaram Ravi Mehrotra 《Journal of biomedical science》2010,17(1):10
Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteinases that are capable of cleaving all extra cellular
matrix (ECM) substrates. Degradation of matrix is a key event in progression, invasion and metastasis of potentially malignant
and malignant lesions of the head and neck. It might have an important polymorphic association at the promoter regions of
several MMPs such as MMP-1 (-1607 1G/2G), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) and TIMP-2 (-418 G/C or
C/C). Tissue inhibitors of metalloproteinases (TIMPs) are naturally occurring inhibitors of MMPs, which inhibit the activity
of MMPs and control the breakdown of ECM. Currently, many MMP inhibitors (MMPIs) are under development for treating different
malignancies. Useful markers associated with molecular aggressiveness might have a role in prognostication of malignancies
and to better recognize patient groups that need more antagonistic treatment options. Furthermore, the introduction of novel
prognostic markers may also promote exclusively new treatment possibilities, and there is an obvious need to identify markers
that could be used as selection criteria for novel therapies. The objective of this review is to discuss the molecular functions
and polymorphic association of MMPs and TIMPs and the possible therapeutic aspects of these proteinases in potentially malignant
and malignant head and neck lesions. So far, no promising drug target therapy has been developed for MMPs in the lesions of
this region. In conclusion, further research is required for the development of their potential diagnostic and therapeutic
possibilities. 相似文献