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Jayanta Bhattacharya Alok Ghosh Chaudhuri Ajoy K. Sinha Ajoy K. Samanta Manoj K. Chakrabarti 《FEMS microbiology letters》1997,156(1):79-83
Escherichia coli heat-stable enterotoxin (STa) was found to bind on the surface of human colonic (COLO 205) cells. The binding of [125I]STa to cell membranes was found to be specific, reversible and saturable. Scatchard analysis of the equilibrium binding demonstrated a single class of binding sites with a Kd of 0.5×10−10 M. Autoradiographic analysis of polyacrylamide gel electrophoresis revealed the specific incorporation of [125I]STa into a single STa binding protein with a molecular mass of 95 kDa. Following incubation of COLO 205 cells with STa, a rise of intracellular cGMP was also evident. 相似文献
326.
S. Samanta, P. Dey and R. Nijhawan The role of micronucleus scoring in fine needle aspirates of ductal carcinoma of the breast Aims and objectives: Micronucleus (MN) scoring was carried out in benign (fibroadenoma) and malignant (infiltrating ductal carcinoma) breast lesions to evaluate the role of MN as a biomarker in breast carcinomas. We also compared MN scores among different cytological grades of breast carcinoma. Materials and methods: A total of 31 archival cases of fibroadenoma (FA) and 40 cases of infiltrating ductal carcinoma (IDC) were selected. The best May‐Grünwald–Giemsa (MGG) stained fine needle aspiration cytology (FNAC) smear of each case was selected. The MN scoring was carried out independently by two observers on 1000 epithelial cells in oil immersion magnification (100× objective). The MN scores in FA and IDC were compared. The IDC cases were graded and the MN scores in different cytological grades of IDC were compared. Results: The mean MN scores (± standard deviation) in FA and IDC were 0.6 (± 1.1) and 13.6 (± 12.8), respectively, which were significantly different (P < 0.0001). There were seven grade 1, 13 grade 2, and 20 grade 3 IDCs. The mean MN scores (± standard deviation) of grade 1, 2 and 3 IDC were 4.3 (± 2.3), 11.95 (± 9.2) and 21.1 (± 16.7), respectively. An analysis of variance (anova ) test showed a significant difference in MN score between all the grades of IDC (P < 0.05). However, there was no significant difference between fibroadenoma and grade 1 IDC. The Pearson’s correlation coefficient showed positive correlations between MN scoring in the different grades of IDC. Conclusions: MN scoring on routinely stained smears of IDCs was significantly higher than in fibroadenoma and was relatively easy, reliable and reproducible. As MN scoring of grade 1 IDC was similar to fibroadenoma, a larger study should be conducted to compare grade 1 IDC with other benign breast lesions. 相似文献
327.
Thalassiosira sundarbana sp. nov. (Bacillariophyta), an estuarine diatom from Sundarbans mangrove ecoregion based on morphology and molecular phylogeny
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A new species of diatom, Thalassiosira sundarbana, is described based on light and scanning electron microscopy along with molecular phylogeny. The specimen was collected from Chemaguri creek of the Indian part of Sundarbans mangroves, and subsequently a clonal culture was established. Thalassiosira sundarbana possess variable numbers of occluded processes, and one labiate process on the valve face. Valve margin is ribbed and areolae are fasciculated on the valve face. Two rings of strutted processes are present on valve face. Strutted processes are also scattered on the valve face apart from the presence of two rings. Valvocopula and copula have rows of pore, and pleurae are hyaline. Bayesian analyses of nuclear encoded small subunit (SSU) rDNA and plastid encoded rbcL gene confirmed that T. sundarbana is phylogenetically novel. Salinity tolerance experiment with the clonal culture of T. sundarbana showed that this isolate can grow in salinity ranging from 10–35 psu. The maximum growth rate was observed in 15 psu salinity (0.5 divisions 24 h?1). On the basis of morphological features and molecular phylogeny, this clonal isolate is considered as a new estuarine species of Thalassiosira. 相似文献
328.
Durbadal Ojha Rashmi Das Parveen Sobia Vedprakash Dwivedi Soma Ghosh Amalesh Samanta Debprasad Chattopadhyay 《PloS one》2015,10(9)
Pedilanthus tithymaloides (PT), a widely used ethnomedicinal plant, has been employed to treat a number of skin conditions. To extend its utility and to fully exploit its medicinal potential, we have evaluated the in vitro antiviral activity of a methanolic extract of PT leaves and its isolated compounds against Herpes Simplex Virus type 2 (HSV-2). Bioactivity-guided studies revealed that the extract and one of its constituents, luteolin, had potent antiviral activity against wild-type and clinical isolates of HSV-2 (EC50 48.5–52.6 and 22.4–27.5 μg/ml, respectively), with nearly complete inhibition at 86.5–101.8 and 40.2–49.6 μg/ml, respectively. The inhibitory effect was significant (p<0.001) when the drug was added 2 h prior to infection, and was effective up to 4 h post-infection. As viral replication requires NF-κB activation, we examined whether the observed extract-induced inhibition of HSV-2 was related to NF-κB inhibition. Interestingly, we observed that treatment of HSV-2-infected cells with extract or luteolin suppressed NF-κB activation. Although NF-κB, JNK and MAPK activation was compromised during HSV replication, neither the extract nor luteolin affected HSV-2-induced JNK1/2 and MAPK activation. Moreover, the PT leaf extract and luteolin potently down-regulated the expression of tumor necrosis factor (TNF)-α, Interleukin (IL)-1β, IL-6, NO and iNOS and the production of gamma interferon (IFN-γ), which are directly involved in controlling the NF-κB signaling pathway. Thus, our results indicate that both PT leaf extract and luteolin modulate the NF-κB signaling pathway, resulting in the inhibition of HSV-2 replication. 相似文献
329.
Biophysics - This paper mainly deals with the prey?predator dynamics where both the prey and predator exhibit herd behavior. Positivity, boundedness, some extinction criteria, stability of... 相似文献
330.
Rosemeire Cobo Zanella Maria Cristina de Cunto Brandileone Ana Lúcia Andrade Cinthya Terumi Ogassavara Cleiton Eduardo Fiório Angela Pires Brand?o Samanta Cristine Grassi Almeida Ana Paula Silva Lemos Maria Cecília Gorla Telma Regina Carvalhanas Helena Sato Bernadete Liphaus Maria Lígia Nerger Monica Conde Ana Freitas Ribeiro 《Memórias do Instituto Oswaldo Cruz》2015,110(6):755-759
The aim of the present study was to assess the prevalence of Haemophilus
influenzae type b (Hib) nasopharyngeal (NP) colonisation among healthy
children where Hib vaccination using a 3p+0 dosing schedule has been routinely
administered for 10 years with sustained coverage (> 90%). NP swabs were collected
from 2,558 children who had received the Hib vaccine, of whom 1,379 were 12-< 24
months (m) old and 1,179 were 48-< 60 m old. Hi strains were identified by
molecular methods. Hi carriage prevalence was 45.1% (1,153/2,558) and the prevalence
in the 12-< 24 m and 48-< 60 m age groups were 37.5% (517/1,379) and 53.9%
(636/1,179), respectively. Hib was identified in 0.6% (16/2,558) of all children in
the study, being 0.8% (11/1,379) and 0.4% (5/1,179) among the 12-< 24 m and
48-< 60 m age groups, respectively. The nonencapsulate Hi colonisation was 43% (n
= 1,099) and was significantly more frequent at 48-< 60 m of age (51.6%, n = 608)
compared with that at 12-< 24 m of age (35.6%, n = 491). The overall resistance
rates to ampicillin and chloramphenicol were 16.5% and 3.7%, respectively; the
co-resistance was detected in 2.6%. Our findings showed that the Hib carrier rate in
healthy children under five years was very low after 10 years of the introduction of
the Hib vaccine. 相似文献