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51.
K Michałek M Laszczyńska AK Ciechanowicz A Herosimczyk I Rotter M Oganowska 《Biotechnic & histochemistry》2014,89(5):342-347
Aquaporin 2 (AQP2) is a small, integral tetrameric plasma membrane protein that is expressed in mammalian kidneys. The specific constitution of this protein and its selective permeability to water means that AQP2 plays an important role in hypertonic urine production. Immunolocalization of AQP2 has been studied in humans, monkeys, sheep, dogs, rabbits, rats, mice and adult cattle. We analyzed the expression of AQP2 in kidneys of 7-month-old Polish-Friesian var. black and white male calves. AQP2 was localized in the principal cells of collecting ducts in medullary rays penetrating the renal cortex and in the collecting ducts of renal medulla. AQP2 was expressed most strongly in the apical plasma membrane, but expression was observed also in the intracellular vesicles and basolateral plasma membrane. Our study provides new information concerning the immunolocalization of AQP2 in calf kidneys. 相似文献
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53.
Wen-Tai Li Anirban Mahapatra David G. Longstaff Gang Zhao Michael K. Chan Joseph A. Krzycki 《Journal of molecular biology》2009,385(4):1156-1164
Pyrrolysine, the 22nd amino acid, is encoded by amber (TAG = UAG) codons in certain methanogenic archaea and bacteria. PylS, the pyrrolysyl-tRNA synthetase, ligates pyrrolysine to tRNAPyl for amber decoding as pyrrolysine. PylS and tRNAPyl have potential utility in making tailored recombinant proteins. Here, we probed interactions necessary for recognition of substrates by archaeal PylS via synthesis of close pyrrolysine analogs and testing their reactivity in amino acid activation assays. Replacement of the methylpyrroline ring of pyrrolysine with cyclopentane indicated that solely hydrophobic interactions with the ring-binding pocket of PylS are sufficient for substrate recognition. However, a 100-fold increase in the specificity constant of PylS was observed with an analog, 2-amino-6-((R)-tetrahydrofuran-2-carboxamido)hexanoic acid (2Thf-lys), in which tetrahydrofuran replaced the pyrrolysine methylpyrroline ring. Other analogs in which the electronegative atom was moved to different positions suggested PylS preference for a hydrogen-bond-accepting group at the imine nitrogen position in pyrrolysine. 2Thf-lys was a preferred substrate over a commonly employed pyrrolysine analog, but the specificity constant for 2Thf-lys was 10-fold lower than for pyrrolysine itself, largely due to the change in Km. The in vivo activity of the analogs in supporting UAG suppression in Escherichia coli bearing genes for PylS and tRNAPyl was similar to in vitro results, with l-pyrrolysine and 2Thf-lys supporting the highest amounts of UAG translation. Increasing concentrations of either PylS substrate resulted in a linear increase in UAG suppression, providing a facile method to assay bioactive pyrrolysine analogs. These results illustrate the relative importance of the H-bonding and hydrophobic interactions in the recognition of the methylpyrroline ring of pyrrolysine and provide a promising new series of easily synthesized pyrrolysine analogs that can serve as scaffolds for the introduction of novel functional groups into recombinant proteins. 相似文献
54.
Annapurna Kumari Paramita Mahapatra Vijay Kumar Garlapati Rintu Banerjee 《Biotechnology for biofuels》2009,2(1):1-7
Background
Transesterification of Jatropha oil was carried out in t-butanol solvent using immobilized lipase from Enterobacter aerogenes. The presence of t-butanol significantly reduced the negative effects caused by both methanol and glycerol. The effects of various reaction parameters on transesterification of Jatropha oil were studied. 相似文献55.
Suman Kanungo Sachin N. Desai Ranjan Kumar Nandy Mihir Kumar Bhattacharya Deok Ryun Kim Anuradha Sinha Tanmay Mahapatra Jae Seung Yang Anna Lena Lopez Byomkesh Manna Barnali Bannerjee Mohammad Ali Mandeep Singh Dhingra Ananga Mohan Chandra John D. Clemens Dipika Sur Thomas F. Wierzba 《PLoS neglected tropical diseases》2015,9(3)
BackgroundA bivalent killed whole cell oral cholera vaccine has been found to be safe and efficacious for five years in the cholera endemic setting of Kolkata, India, when given in a two dose schedule, two weeks apart. A randomized controlled trial revealed that the immune response was not significantly increased following the second dose compared to that after the first dose. We aimed to evaluate the impact of an extended four week dosing schedule on vibriocidal response.Conclusions/SignificanceComparable immune responses and safety profiles between the two dosing schedules support the option for increased flexibility of current OCV dosing. Further operational research using a longer dosing regimen will provide answers to improve implementation and delivery of cholera vaccination in endemic and epidemic outbreak scenarios. 相似文献
56.
The sequences of the 5' long-terminal repeat (LTR) and adjacent leader
regions of 27 full-length copia elements isolated from natural populations
of Drosophila melanogaster, D. simulans, and D. mauritiana are presented.
Phylogenetic analyses indicate that although D. melanogaster copia elements
are distinct from those of D. simulans and D. mauritiana, the elements of
these latter two species are not distinguishable from one another. LTRs and
adjacent 5' leader regions of elements isolated from D. simulans and D.
mauritiana are structurally similar to one another and carry substantial
deletional variation mapping to regions previously identified as being of
potential importance for copia expression.
相似文献
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58.
Qinghua Zhang Feifei Huang Zaoling Liu Na Zhang Tanmay Mahapatra Weiming Tang Yang Lei Yali Dai Songyuan Tang Jingping Zhang 《PloS one》2016,11(4)
BackgroundConsidering the importance of health literacy (HL) for the maximum yield from the hypertension control programs, development of a reliable and valid instrument of hypertension-related HL is critical. This study aimed to translate and validate the High Blood Pressure-Health Literacy Scale (HBP-HLS) into Chinese (C-HBP-HLS) and evaluate its psychometric properties in Chinese context.MethodBetween June 2013 and January 2014, a cross-sectional study was conducted among recruited hypertensive patients belonging to the Han and Kazakh-Chinese communities in Urumqi, Xinjiang, China.ResultsA pilot sample (n = 242) was selected for the exploratory factor analysis of the translated and modified instrument. Another sample (n = 308) was recruited for the confirmatory factor analysis. C-HBP-HLS consisted of five dimensions (Print Health Literacy, Medication Label, Understanding Ability, Newest Vital Sign Test, and Avoiding Food Allergy) containing 15 items, accounting for 77.7% of the total variance. The 5-factor model demonstrated a good overall fit. The scale-level content validity index was 0.85. Cronbach’s alpha of the overall scale was 0.78 and test-retest reliability was 0.96. Education level had a strong positive correlation with the scores for items Q1, Q2, and Q3(r = 0.481, 0.492, 0.475, respectively). Health Literacy scores among Kazakh patients were significantly lower than Han (7.13±7.90 vs. 30.10±13.42, Z = -14.573, P<0.001).ConclusionC-HBP-HLS demonstrated suitable factor structure and robust psychometric properties for measuring health literacy level among hypertensive patients in China. 相似文献
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60.
Pravati Kumari Mahapatra Priyambada Mohanty-Hejmadi 《Development, growth & differentiation》1994,36(3):307-317
In this study the effects of vitamin A on tadpoles of Polypedates maculatus with an amputated tail were investigated. After amputation of half the tail at the hindlimb-bud stage, tadpoles were exposed to vitamin A (palmitate) 10 IU/ml solution for 24 hr (Group I), 48 hr (II), 72 hr (III), 96 hr (IV), 120 hr (V) or 144 hr (VI). Vitamin A was deleterious to survival of the tadpoles since 10, 30 and 30% tadpoles died from Group IV, V and VI, respectively before the emergence of forelimbs. Regeneration of the tail was abnormal in 91.7% of the tadpoles. Vitamin A induced homeotic transformation of the amputated tail to hindlimbs in 11.6% of the animals. Normal limb development was suppressed partially or completely in 48.3% tadpoles. These results indicate that in addition to traumatic effects, vitamin A can lead to homeotic transformation of the tail into hindlimbs and can also interfere with normal development of limbs. 相似文献