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81.
Savita Rani Sanjeev Kumar Syed Mudassir Jeelani Raghbir Chand Gupta Santosh Kumari 《Plant Systematics and Evolution》2012,298(2):485-497
At present 14 species of Potentilla L. have been cytologically worked out from different geographical areas of Kashmir and Himachal Pradesh in the Western Himalayas.
New chromosome numbers in nine species—Potentilla argyrophylla (n = 14), P. atrosanguinea (n = 7, 14), P. desertorum (n = 7), P. gerardiana (n = 14), P. indica (n = 14), P. micropetala (n = 14), P. nepalensis (n = 14), P. sibbaldia (n = 14) and P. thomsonii (n = 7)—have been reported on a worldwide basis for the first time. Additional chromosomal races of polyploid cytotypes for
P. argyrophylla (n = 28) and P. desertorum (n = 14) along with a diploid cytotype for P. micropetala (n = 7) plus diploid cytotypes for the five species as P. fulgens (n = 7), P. gelida (n = 7), P. kleiniana (n = 7), P. sibbaldia (n = 7) and P. sundaica (n = 7) as well as a tetraploid cytotype for P. fruticosa (n = 14) all have been cytologically worked out from India for the first time. The course of meiosis varies from normal to abnormal
in different populations of the majority of the species, such as P. argyrophylla, P. atrosanguinea, P. desertorum, P. fruticosa, P. fulgens, P. gelida, P. indica, P. nepalensis, P. sibbaldia and P. sundaica, except for normal meiosis observed in P. gerardiana, P. kleiniana, P. micropetala and P. thomsonii. The anomalous taxa are marked with meiotic abnormalities in the form of cytomixis, chromosomal stickiness, unoriented bivalents,
formation of laggards and bridges resulting in abnormal microsporogenesis, and production of heterogenous-sized fertile pollen
grains along with reduced pollen fertility. All the taxa with normal meiotic courses show nearly one hundred percent pollen
fertility. 相似文献
82.
S Sahu K Ray MS Yogendra Kumar S Gupta H Kauser S Kumar K Mishra U Panjwani 《Phytomedicine》2012,19(10):924-929
The present study was performed to investigate the effects of Valeriana wallichi (VW) aqueous root extract on sleep-wake profile and level of brain monoamines on Sprague-Dawley rats. Electrodes and transmitters were implanted to record EEG and EMG in freely moving condition and the changes were recorded telemetrically after oral administration of VW in the doses of 100, 200 and 300 mg/kg body weight. Sleep latency was decreased and duration of non-rapid eye movement (NREM) sleep was increased in a dose dependent manner. A significant decrease of sleep latency and duration of wakefulness were observed with VW at doses of 200 and 300 mg/kg. Duration of NREM sleep as well as duration of total sleep was increased significantly after treatment with VW at the doses of 200 and 300 mg/kg. VW also increased EEG slow wave activity during NREM sleep at the doses of 200 and 300 mg/kg. Level of norepinephrine (NE), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), serotonin (5-HT) and hydroxy indole acetic acid (HIAA) were measured in frontal cortex and brain stem after VW treatment at the dose of 200mg/kg. NE and 5HT level were decreased significantly in both frontal cortex and brain stem. DA and HIAA level significantly decreased only in cortex. DOPAC level was not changed in any brain region studied. In conclusion it can be said that VW water extract has a sleep quality improving effect which may be dependent upon levels of monoamines in cortex and brainstem. 相似文献
83.
Simonin J Vernekar SK Thompson AJ Hothersall JD Connolly CN Lummis SC Lochner M 《Bioorganic & medicinal chemistry letters》2012,22(2):1151-1155
The synthesis, photophysical and biological characterization of a small library of fluorescent 5-HT(3) receptor ligands is described. Several of these novel granisetron conjugates have high quantum yields and show high affinity for the human 5-HT(3)AR. 相似文献
84.
This article deals with the optimization of the various parameters for production of phytase using Achromobacter sp. PB‐01 in submerged fermentation (SmF). A semisynthetic medium containing ingredients of phytase screening media (PSM) supplemented with 2% (w/v) sucrose, 1% (w/v) peptone, and 10% (w/v) wheat bran was found to be the best production medium among the various combinations tried. Among various surfactants added to SmF, Triton X‐100 (0.1%) exhibited a 16% increase in phytase activity. An overall 11.2 fold enhancement in enzyme activity (0.79 U/mL→8.84 U/mL) was attained when SmF was carried out using 0.5% (v/v) inoculum of a 15 h old culture of Achromobacter sp. PB‐01 at an initial pH of 5.5, temperature 30°C and allowed to grow for 48 h. Presence of accessory hydrolytic enzymes in the crude extract further added value as feed additive by mediating efficient degradation of non‐starch polysaccharides (NSP). In addition, we also investigated the efficacy of phytase on different agro‐industrial residues using in vitro experiments that simulated the conditions of the digestive tract. Results indicate that phytase from our source hydrolyze phytate efficiently with the concomitant liberation of inorganic phosphate, protein, reducing sugar, and calcium. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012 相似文献
85.
Background
Carcinoma of gallbladder (GBC) is an aggressive malignancy. The higher incidence of gallbladder cancer in women has been partly attributed to hormonal factors. Therefore the present study was designed to explore the role of genetic variants in estrogen (ESR1, ESR2) and progesterone (PGR) receptors in conferring risk of gallbladder cancer.Materials and Methods
The present case-control study recruited total of 860 subjects, including 410 GBC patients, 230 gallstone patients and 220 controls. We examined the associations of 6 selected polymorphisms in three genes: ESR1 (rs2234693, rs9340799, rs1801132), ESR2 (rs1271572, rs1256049) and PGR (rs1042838) with GBC risk. Genotyping for all the polymorphisms was done using PCR-RFLP. Multifactor dimensionality reduction and classification and regression tree approaches were combined with logistic regression to discover high-order gene-gene interactions in hormonal pathway.Results
On comparing the genotype frequency distribution in gallstone and GBC patients with that of healthy subjects, the homozygous variant genotypes of ESR1-397TT (rs2234693) polymorphism showed significant risk for developing gallstone [odds ratio: OR = 2.9] and GBC [OR = 1.8] respectively. Detailed haplotypes analysis suggested that ESR1 T rs2234693G rs9340799C rs1801132 have significant association in conferring risk for both gallstones [OR = 2.2] and GBC [OR = 3.0]. However, the variant-containing genotypes (DI+II) of PGR (rs1042838) showed low risk in both GBC [OR = 0.4] and gallstone patients [OR = 0.4].On performing the MDR analysis, ESR1 IVS1-397C>T, ESR1 IVS1-351A>G, and ESR2-789 A>C yielded the highest testing accuracy of 0.634. These results were further supported by the CART analysis which revealed that individuals with the combined genotypes of ESR1-397 CT or TT, ESR1-351 AG or GG and ESR2 -789 AA had the highest risk for GBC [OR = 3.9].Conclusion
Using multi-analytical approaches, our study showed important role of ESR1 IVS1-397C>T, ESR1 IVS1-351A>G, and ESR2-789 A>C variants in GBC susceptibility and the risk appears to be mediated through gallstone dependent pathway. 相似文献86.
Halwani R Boyer JD Yassine-Diab B Haddad EK Robinson TM Kumar S Parkinson R Wu L Sidhu MK Phillipson-Weiner R Pavlakis GN Felber BK Lewis MG Shen A Siliciano RF Weiner DB Sekaly RP 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(12):7969-7979
DNA vaccination is an invaluable approach for immune therapy in that it lacks vector interference and thus permits repeated vaccination boosts. However, by themselves, DNA-based vaccines are typically poor inducers of Ag-specific immunity in humans and non-human primates. Cytokines, such as IL-12 and IL-15, have been shown to be potent adjuvants for the induction and maintenance of cellular immune responses, in particular during HIV infection. In this study, we examined the ability of therapeutic vaccination with SIV-DNA+IL-12 or IL-15 as molecular adjuvants to improve DNA vaccine potency and to enhance memory immune responses in SIV-infected macaques. Our results demonstrate that incorporating IL-12 into the vaccine induces SIV-specific CD8 effector memory T cell (T(EM)) functional responses and enhances the capacity of IFN-gamma-producing CD8 T(EM) cells to produce TNF. Lower levels of PD-1 were expressed on T cells acquiring dual function upon vaccination as compared with mono-functional CD8 T(EM) cells. Finally, a boost with SIV-DNA+IL-15 triggered most T cell memory subsets in macaques primed with either DNA-SIV or placebo but only CD8 T(EM) in macaques primed with SIV-DNA+IL-12. These results indicate that plasmid IL-12 and IL-15 cytokines represent a significant addition to enhance the ability of therapeutic DNA vaccines to induce better immunity. 相似文献
87.
Regulation of stem cell (SC) proliferation is central to tissue homoeostasis, injury repair, and cancer development. Accumulation of replication errors in SCs is limited by either infrequent division and/or by chromosome sorting to retain preferentially the oldest 'immortal' DNA strand. The frequency of SC divisions and the chromosome-sorting phenomenon are difficult to examine accurately with existing methods. To address this question, we developed a strategy to count divisions of hair follicle (HF) SCs over time, and provide the first quantitative proliferation history of a tissue SC during its normal homoeostasis. We uncovered an unexpectedly high cellular turnover in the SC compartment in one round of activation. Our study provides quantitative data in support of the long-standing infrequent SC division model, and shows that HF SCs do not retain the older DNA strands or sort their chromosome. This new ability to count divisions in vivo has relevance for obtaining basic knowledge of tissue kinetics. 相似文献
88.
The MUC1 protein is aberrantly expressed on many solid tumor cancers. In contrast to its apical clustering on healthy epithelial cells, it is uniformly distributed over cancer cells. However, a mechanistic link between aberrant expression and cancer has remained elusive. Herein, we report that a membrane-bound MUC1 cleavage product, that we call MUC1*, is the predominant form of the protein on cultured cancer cells and on cancerous tissues. Further, we demonstrate that transfection of a minimal fragment of MUC1, MUC1*(1110), containing a mere forty-five (45) amino acids of the extracellular domain, is sufficient to confer the oncogenic activities that were previously attributed to the full-length protein. By comparison of molecular weight and function, it appears that MUC1* and MUC1*(1110) are approximately equivalent. Evidence is presented that strongly supports a mechanism whereby dimerization of the extracellular domain of MUC1* activates the MAP kinase signaling cascade and stimulates cell growth. These findings suggest methods to manipulate this growth mechanism for therapeutic interventions in cancer treatments. 相似文献
89.
Runx1 modulates developmental, but not injury-driven, hair follicle stem cell activation 总被引:1,自引:0,他引:1
Osorio KM Lee SE McDermitt DJ Waghmare SK Zhang YV Woo HN Tumbar T 《Development (Cambridge, England)》2008,135(6):1059-1068
Aml1/Runx1 controls developmental aspects of several tissues, is a master regulator of blood stem cells, and plays a role in leukemia. However, it is unclear whether it functions in tissue stem cells other than blood. Here, we have investigated the role of Runx1 in mouse hair follicle stem cells by conditional ablation in epithelial cells. Runx1 disruption affects hair follicle stem cell activation, but not their maintenance, proliferation or differentiation potential. Adult mutant mice exhibit impaired de novo production of hair shafts and all temporary hair cell lineages, owing to a prolonged quiescent phase of the first hair cycle. The lag of stem cell activity is reversed by skin injury. Our work suggests a degree of functional overlap in Runx1 regulation of blood and hair follicle stem cells at an equivalent time point in the development of these two tissues. 相似文献
90.
Isolation, identification and application of novel bacterial consortium TJ-1 for the decolourization of structurally different azo dyes 总被引:2,自引:0,他引:2
A novel bacterial consortium (TJ-1), which could decolorize Acid Orange 7 (AO7) and manyother azo dyes, was developed. In TJ-1 three bacterial strains were identified as Aeromonas caviae, Proteus mirabilis and Rhodococcus globerulus by 16S rRNA gene sequence analysis. AO7 decolorization was significantly higher with the use of consortium as compared to the use of individual strains, indicating complementary interactions among these strains. AO7 decolorization was observed under microaerophilic condition in the presence of organic carbon source. Either yeast extract (YE) alone or a combination of YE and glucose resulted in much higher decolorization of AO7 as compared to glucose alone, peptone or starch. Kinetic studies with different initial AO7 concentrations showed that more than 90% decolorization could be achieved even at 200mg/l within 16h. Fed-batch studies showed that AO7 decolorization required 10h during the first cycle and 5h in the second and third cycles, showing that bacterial cells could be used for multiple cycles. The consortium also decolorized fifteen other azo dyes individually as well as a simulated wastewater containing a mixture of all the sixteen azo dyes, thus, conferring the possibility of application of TJ-1 for the treatment of industrial wastewaters. 相似文献