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91.
TRPM8 is required for cold sensation in mice 总被引:12,自引:0,他引:12
ThermoTRPs, a subset of the Transient Receptor Potential (TRP) family of cation channels, have been implicated in sensing temperature. TRPM8 and TRPA1 are both activated by cooling; however, it is unclear whether either ion channel is required for thermosensation in vivo. We show that mice lacking TRPM8 have severe behavioral deficits in response to cold stimuli. In thermotaxis assays of temperature gradient and two-temperature choice assays, TRPM8-deficient mice exhibit strikingly reduced avoidance of cold temperatures. TRPM8-deficient mice also lack behavioral response to cold-inducing icilin application and display an attenuated response to acetone, an unpleasant cold stimulus. However, TRPM8-deficient mice have normal nociceptive-like responses to subzero centigrade temperatures, suggesting the presence of at least one additional noxious cold receptor. Finally, we show that TRPM8 mediates the analgesic effect of moderate cooling after administration of formalin, a painful stimulus. Therefore, depending on context, TRPM8 contributes to sensing unpleasant cold stimuli or mediating the effects of cold analgesia. 相似文献
92.
Increasing air pollution has resulted in ozone depletion, which has led to an increase in the amount of ultraviolet (UV) radiation reaching the surface of earth posing hazardous effects on the plant yield. The chlorophyll a fluorescence transients were recorded in vivo using plant efficiency analyzer and analyzed according to JIP test, which can monitor photosystem II (PSII) behavior. This study aims to evaluate the sensitivity of different components of PSII to UV radiations and the extent of damage caused when wheat plants were exposed to UV radiations for 2 and 4 h. It was observed that functional disconnection of light harvesting complexes from PSII complex, accumulation of inactive reaction center, inactivation of oxygen evolving complex, and thus the linear electron transport process (ET0/CS), were drastically affected by UV radiations. This study will contribute to understanding of the basic photosynthetic mechanisms affected in crop plants due to increased UV radiations. The knowledge obtained will be relevant for environmental and plant scientists to plan strategies to cope with stresses. 相似文献
93.
A cell-based assay and a solution neonatal Fc receptor (FcRn) binding assay were implemented for the characterization of an IgG2 antibody after observation that different product lots exhibited unexpected differences in FcRn binding in the cell-based format with membrane-bound FcRn. The experiments described here suggest that the apparent differences observed in the FcRn binding across different product lots in the cell-based format can be attributed to the different levels of the higher order high molecular weight species (HMWs) in them. A strong correlation between FcRn binding in the cell-based format and the percentage (%) higher order HMWs suggests that small amounts (∼0.1%) of the latter could cause the enhanced apparent FcRn binding (% relative binding ranging from 50 to 100%) in the format. However, when the binding was assessed with recombinant FcRn in soluble form, avidity effects were minimal and the assay format exhibited less sensitivity toward the differences in higher order HMWs levels across product lots. In conclusion, a solution-based assay may be a more appropriate assay to assess FcRn binding of the dominant species of an Fc-fusion protein or monoclonal antibody if minor differences in product variants such as higher order HMWs are shown to affect the binding significantly. 相似文献
94.
Raman Dhariwal Vijay Gahlaut Bhaganagare R. Govindraj Dharmendra Singh Saloni Mathur Shailendra Vyas Rajib Bandopadhyay Jitendra Paul Khurana Akhilesh Kumar Tyagi Kumble Vinod Prabhu Kunal Mukhopadhyay Harindra Singh Balyan Pushpendra Kumar Gupta 《Functional & integrative genomics》2015,15(2):233-245
95.
S. Agarwal, R. Gupta, V. K. Iyer, S. R. Mathur and R. Ray Cytopathological diagnosis of alveolar soft part sarcoma, a rare soft tissue neoplasm Objective: Alveolar soft part sarcoma (ASPS) is a rare soft tissue neoplasm, having various morphological mimics, especially on fine needle aspiration cytology (FNAC). Because no definite immunohistochemical markers are available to aid a correct diagnosis, knowledge of the cytomorphological features is essential for correct patient management. Cytological features of five cases of ASPS are discussed, along with the ultrastructural findings available in one of them. Methods: Cytology records from 1997 to 2009 were reviewed for cases with a diagnosis of ASPS on cytology. The histology slides of the cases were also assessed for confirmation of the diagnosis. All the slides were reviewed by three pathologists. Results: There were five cases of ASPS diagnosed on FNAC. Their cytological features were noted in detail. The diagnoses in all the cases were confirmed on histology, and ultrastructural findings available in one of them were also assessed. Conclusions: The knowledge of cytological features may aid in diagnosing this rare tumour correctly on FNA smears, thus enabling correct patient management. 相似文献
96.
Gopinath KP Kathiravan MN Srinivasan R Sankaranarayanan S 《Bioresource technology》2011,102(4):3687-3693
In this study, it was attempted to evaluate the influences and also recommended some elimination methods for inhibitory effects offered by salts and heavy metal ions. Congo red dye solution treated with mutant Pseudomonas sp. was taken as a model system for study. The salts used in this study are NaCl, CaCl2 and MgSO4·7H2O. Though the growth was inhibited at concentrations above 4 g/l, toleration was achieved by acclimatization process. In case of heavy metal ions, Cr (VI) showed low inhibition up to 500 mg/l of concentration, compared to Zn (II) and Cu (II). It was due to the presence of chromium reductase enzyme which was confirmed by SDS-PAGE. Zn (II) and Cu (II) ion inhibitions were eliminated by chelation with EDTA. The critical ion concentrations obtained as per Han-Levenspiel model for Cr (VI), Zn (II) and Cu (II) were 0.8958, 0.3028 and 0.204 g/l respectively. 相似文献
97.
miRNA response to DNA damage 总被引:1,自引:0,他引:1
Faithful transmission of genetic material in eukaryotic cells requires not only accurate DNA replication and chromosome distribution but also the ability to sense and repair spontaneous and induced DNA damage. To maintain genomic integrity, cells undergo a DNA damage response using a complex network of signaling pathways composed of coordinate sensors, transducers and effectors in cell cycle arrest, apoptosis and DNA repair. Emerging evidence has suggested that miRNAs play a crucial role in regulation of DNA damage response. In this review, we discuss the recent findings on how miRNAs interact with the canonical DNA damage response and how miRNA expression is regulated after DNA damage. 相似文献
98.
99.
Mathur J 《BioEssays : news and reviews in molecular, cellular and developmental biology》2005,27(4):377-387
The seven-subunit ARP2/3 complex is an efficient modulator of the actin cytoskeleton with well-recognized roles in amoeboid locomotion and subcellular motility of organelles and microbes. The recent identification of different subunit homologs suggests the existence of a functional ARP2/3 complex in higher plants. Mutations in some of the subunits have revealed a pivotal role for the complex in determining the shape of walled cells and focused attention on the interlinked processes of cortical-actin organization, growth-site selection, organelle motility and actin-microtubule interactions during plant cell morphogenesis. The findings supporting a global conservation of molecular mechanisms for membrane protrusion have been further strengthened by the identification of plant homologs of upstream regulators of the complex such as PIR121, NAP125 and HSPC300. As discussed here, the recent studies suggest that there might be hitherto unappreciated molecular and cell-biological commonalities between protrusion mediated motility of animal cells and polarized, expansion-mediated growth of plant cells. 相似文献
100.
Das B Rudra S Yadav A Ray A Rao AV Srinivas AS Soni A Saini S Shukla S Pandya M Bhateja P Malhotra S Mathur T Arora SK Rattan A Mehta A 《Bioorganic & medicinal chemistry letters》2005,15(19):4261-4267
Novel oxazolidinones were synthesized containing a number of substituted five-membered heterocycles attached to the 'piperazinyl-phenyl-oxazolidinone' core of eperezolid. Further, the piperazine ring of the core was replaced by other diamino-heterocycles. These modifications led to several compounds with potent activity against a spectrum of resistant and susceptible gram-positive organisms, along with the identification of ranbezolid (RBx 7644) as a clinical candidate. 相似文献