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51.
Das DK Mallik MK Sharma P Sheikh ZA Mathew PA Sheikh M Mirza K Madda JP Francis IM Junaid TA 《Acta cytologica》2004,48(3):325-336
OBJECTIVE: To study the fine needle aspiration (FNA) cytologic features of papillary thyroid carcinoma (PTC) with special reference to its tall cell variant (TCV), which is the most aggressive of the variants. STUDY DESIGN: Fifty-four PTC cases were classified into variants, and the frequency of well-known morphologic criteria was determined. Four parameters were quantitatively analyzed based on a study of 200 consecutive neoplastic follicular cells: shape of cells, color of cytoplasm, intranuclear cytoplasmic inclusion (INCI) and nuclear grooves. RESULTS: The PTC cases included 6 TCV (> or = 30% tall cells), 8 cases with a significant tall cell component (sig. TCC) having 10-29% tall cells, 17 usual variant (UV), 17 follicular variant (FV) and 6 miscellaneous variants. TCV differed significantly from UV and FV in having a higher tall cell count, higher count of cells with reddish cytoplasm and INCI, and higher frequency of cases with lymphocytic infiltration. PTC (with significant tall cell component [TCC]) differed significantly from TCV with regard to tall cell count and lymphocytic infiltration, from UV with respect to tall cell count and monolayered sheets, and from FV with respect to tall cells, INCI, grooved nuclei, acinar formation, fire-flare appearance and giant cells. CONCLUSION: TCV was cytologically distinct from other variants. The biologic behavior of PTC cases with significant TCC, which morphologically seem to be a group intermediate between TCV on the one hand and UV and FV on the other, however, needs to be carefully monitored. 相似文献
52.
ZNF652, a novel zinc finger protein, interacts with the putative breast tumor suppressor CBFA2T3 to repress transcription 总被引:2,自引:0,他引:2
53.
Prem Raj B. Joseph Jose M. Sarmiento Anurag K. Mishra Sandhya T. Das Roberto P. Garofalo Javier Navarro Krishna Rajarathnam 《The Journal of biological chemistry》2010,285(38):29262-29269
All chemokines share a common structural scaffold that mediate a remarkable variety of functions from immune surveillance to organogenesis. Chemokines are classified as CXC or CC on the basis of conserved cysteines, and the two subclasses bind distinct sets of GPCR class of receptors and also have markedly different quaternary structures, suggesting that the CXC/CC motif plays a prominent role in both structure and function. For both classes, receptor activation involves interactions between chemokine N-loop and receptor N-domain residues (Site-I), and between chemokine N-terminal and receptor extracellular/transmembrane residues (Site-II). We engineered a CC variant (labeled as CC-CXCL8) of the chemokine CXCL8 by deleting residue X (CXC → CC), and found its structure is essentially similar to WT. In stark contrast, CC-CXCL8 bound poorly to its cognate receptors CXCR1 and CXCR2 (Ki > 1 μm). Further, CC-CXCL8 failed to mobilize Ca2+ in CXCR2-expressing HL-60 cells or recruit neutrophils in a mouse lung model. However, most interestingly, CC-CXCL8 mobilizes Ca2+ in neutrophils and in CXCR1-expressing HL-60 cells. Compared with the WT, CC-CXCL8 binds CXCR1 N-domain with only ∼5-fold lower affinity indicating that the weak binding to intact CXCR1 must be due to its weak binding at Site-II. Nevertheless, this level of binding is sufficient for receptor activation indicating that affinity and activity are separable functions. We propose that the CXC motif functions as a conformational switch that couples Site-I and Site-II interactions for both receptors, and that this coupling is critical for high affinity binding but differentially regulates activation. 相似文献
54.
Vengadesan G Amutha S Muruganantham M Anand RP Ganapathi A 《Plant cell reports》2006,25(11):1174-1180
Transgenic herbicide tolerant Acacia sinuata plants were produced by transformation with the bar gene conferring phosphinothricin resistance. Precultured hypocotyl explants were infected with Agrobacterium tumefaciens strain EHA105 in the presence of 100 μM acetosyringone and shoots regenerated on MS (Murashige and Skoog, 1962, Physiol Plant 15:473–497) medium with 13.3 μM benzylaminopurine, 2.6 μM indole-3-acetic acid, 1 g l−1 activated charcoal, 1.5 mg l−1 phosphinothricin, and 300 mg l−1 cefotaxime. Phosphinothricin at 1.5 mg l−1 was used for the selection. Shoots surviving selection on medium with phosphinothricin expressed GUS. Following Southern hybridization, eight independent shoots regenerated of 500 cocultivated explants were demonstrated to be transgenic, which represented transformation frequency of 1.6%. The transgenics carried one to four copies of the transgene. Transgenic shoots were propagated as microcuttings in MS medium with 6.6 μM 6-benzylaminopurine and 1.5 mg l−1 phosphinothricin. Shoots elongated and rooted in MS medium with gibberellic acid and indole-3-butyric acid, respectively both supplemented with 1.5 mg l−1 phosphinothricin. Micropropagation of transgenic plants by microcuttings proved to be a simple means to bulk up the material. Several transgenic plants were found to be resistant to leaf painting with the herbicide Basta. 相似文献
55.
56.
Gupta SK Srivastava R Kuittinen M Mathur N Saxena PN 《Alternatives to laboratory animals : ATLA》2006,34(5):491-498
To establish the use of Metaphire posthuma as a sensitive model for ecotoxicological studies, the comparative effects of five metals on the hatching profiles of the cocoons of the earthworms, Metaphire posthuma, Eisenia foetida and Perionyx excavatus, were studied. The cocoons of the three species of earthworms were exposed to copper, chromium (III), chromium (VI), lead and zinc at 1.25, 2.5, 5.0 and 10.0 ppm. Viable cocoons were incubated at 20 +/- degrees C by using the immersion method. The results indicated that the inhibition of cocoon hatching was concentration dependent. The normal hatching, delayed hatching and non-viability of cocoons were recorded. At a concentration of 1.25 ppm, there was almost no effect on the hatching of the cocoons of all three species of earthworms, except when exposed to chromium (VI), but higher concentrations (2.5 and 5.0 ppm) caused severe effects. It was concluded that M. posthuma was more sensitive than the other two species, and that it is a suitable model for use in ecotoxicity testing. 相似文献
57.
58.
Plant based medicines have gained popularity worldwide due to their almost negligible side effects. In India, the three traditional medicinal systems, namely homeopathy, Ayurveda and Siddha rely heavily on plants for medicinal formulations. To prevent the indiscriminate collection of these valuable medicinal plants and for their proper authentication and conservation, it is imperative to go for sustained efforts towards proper germplasm cataloguing and devising conservation strategies. For this purpose, molecular markers have a significant role, as they provide information ranging from diversity at nucleotide level (single nucleotide polymorphisms) to gene and allele frequencies (genotype information), the extent and distribution of genetic diversity, and population structure. Over the past twenty years, the molecular marker field has completely transformed the meaning of conservation genetics which has emerged from a theory-based field of population biology to a full-fledged pragmatic discipline. In this review, we have explored the transition and transformation of molecular marker technologies throughout these years. 相似文献
59.
Uncontrolled microbial methane production is playing an important role in global warming. In the present study, we showed that water content and incubation temperature increase the potential for methane formation in the two alpine soils under investigation. Beside these factors, the grazing of cows and thus the amendment of methanogenic microorganisms by cattle dung is the most important factor determining the potential of methane production in those soils. 相似文献
60.