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1.
The aim of the present investigation was to study the pineal activity during the seasonal gonadal cycle in both sexes of the Indian tree pie (Dendrocitta vagabunda). The findings revealed that the nuclear diameter of the pineal parenchymal cells moderately decreased and was followed by a moderate increase in the cell population density (per microscopic field of the pineal sections) and serotonin content of the gland during the progressive phase. The values of these parameters were further altered (decreased nuclear diameter with increased cell population density and serotonin level) during breeding but were reversibly altered to some extent during the regression phase, and further altered during the nonbreeding phase in both sexes of the birds. It is suggested that the pineal activity distinctly varies with the seasonal gonadal cycle, being minimum during breeding and maximum during nonbreeding in both sexes of the tree pie. 相似文献
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3.
Chakraborty S Garg P Ramamurthy T Thungapathra M Gautam JK Kumar C Maiti S Yamasaki S Shimada T Takeda Y Ghosh A Nair GB 《Journal of medical microbiology》2001,50(10):879-888
This study identified 17 matching serogroups of Vibrio cholerae belonging to serogroups other than O1 and O139 isolated from human cases and from the environment during a concurrent clinical and environmental study conducted in Calcutta, a cholera endemic area. Isolates within these matching serogroups were compared by various phenotypic and genotypic traits to determine if the environment was the source of the organisms associated with the disease. Clinical strains of V. cholerae were resistant to a greater number of drugs and exhibited multi-drug resistance compared with their environmental counterparts. Except for the presence of the genes for the El Tor haemolysin and the regulatory element ToxR in most of the strains of V. cholerae examined, non-O1, non-O139 V. cholerae strains lacked most of the other known virulence traits associated with toxigenic V. cholerae O1 or O139. Restriction fragment-length polymorphism of virulence-associated genes, ribotypes and DNA fingerprints of strains of matched serogroups showed considerable diversity, although some gene polymorphisms and ribotypes of a few strains of different serogroups were similar. It is concluded that despite sharing the same serogroup, environmental and clinical isolates were genetically heterogeneous and were of different lineages. 相似文献
4.
Maiti PK Bose R Bandyopadhyay S Bhattacharya S Dey JB Ray A 《Indian journal of pathology & microbiology》2004,47(2):295-297
Subcutaneous mycoses caused by the family Entomophthoraceae is very rare type of disease and is being reported sporadically from various Tropical countries including India. Here we report 8 cases of rhinoentomophthoromycosis caused by Conidiobolous coronatus and 7 cases of chronic subcutaneous phycomycosis caused by Basidiobolus ranarum. Cases were detected during a span of 9 years between 1991 to 1999, from 9 districts in and around Kolkata (Eastern India). Former type of lesions were detected among 20 to 65 age group of healthy individuals, predominantly males (7:1). In the latter type, male-female ratio was 2:5, and except for one all cases belonged to below 20 years age group of healthy individuals. Several cases were detected only after examination of repeat biopsy samples. With high degree of clinical suspicion, right approach is needed for laboratory confirmation of diagnosis. 相似文献
5.
Isolation and preliminary characterization of Escherichia coli mutants resistant to lethal action of the bacteriophage lambda P gene. 总被引:1,自引:0,他引:1
Both spontaneous and NTG-induced mutants of Escherichia coli 594 insensitive to the lethal action of lambda P gene were isolated and called rpl (resistant to P lethality). These mutants were of two types, showing different phenotypes. On type I rpl mutants, lambda cl- and lambda v1v3 did not plate, while lambda vir, lambda cl- c17, lambda imm434, and lambda imm21 did; plasmid pMR45 carrying the lambda P gene could not complement lambda imm21P- phage in type I mutants. On the other hand, the type II rpl mutants support the growth of all the above phages including lambda cl-. Neither type of rpl mutation affects growth of the bacteria. 相似文献
6.
Suhrid Maiti Debaki Ranjan Howlader Prolay Halder Ushasi Bhaumik Moumita Dutta Shanta Dutta Hemanta Koley 《Vaccine》2021,39(2):380-393
Invasive non-typhoidal Salmonella (iNTS) serovars, especially Salmonella Typhimurium (ST) and Salmonella Enteritidis (SE), cause gastroenteritis worldwide. Due to the emergence of multi-drug resistance in iNTS, a broad-spectrum vaccine is urgently needed for the prevention of iNTS infection. Currently, there is no effective licensed vaccine against iNTS available in the market. We have formulated an outer membrane vesicles (OMVs) based bivalent immunogen as a vaccine candidate to generate broad-spectrum protective immunity against both recently circulating prevalent ST and SE. We have isolated OMVs from ST and SE and formulated the immunogen by mixing both OMVs (1:1 ratio). Three doses of bivalent immunogen significantly induced humoral immune responses against lipopolysaccharides (LPSs) and outer membrane proteins (OMPs) as well as a cell-mediated immune response in adult mice. We also observed that proteins of OMVs act as an adjuvant for generation of high levels of anti-LPS antibodies through T cell activation. We then characterized the one-day old suckling mice model for both ST and SE mediated gastroenteritis and used the model for a passive protection study. In the passive protection study, we found the passive transfer of bivalent OMVs immunized sera significantly reduced ST and SE mediated colonization and gastroenteritis symptoms in the colon of suckling mice compared to non-immunized sera recipients. The overall study demonstrated that OMVs based bivalent vaccine could generate broad-spectrum immunity against prevalent iNTS mediated gastroenteritis. This study also established the suckling mice model as a suitable animal model for vaccine study against iNTS mediated gastroenteritis. 相似文献
7.
Kapp Judith A.; Pierce Carl W.; Webb David R.; Devens Bruce; Godfrey Wayne; Fukuse Satoshi; Engleman Edgar; Lake Jeffrey P.; Magnani John I.; Maiti Pradip K.; Sehon Alec 《International immunology》1995,7(8):1319-1330
Although reliable antibodies are available that distinguishhuman suppressor T (Ts) cells from CTL and other T cells, feware available for murine Ts cells. We have developed a mAb (984D4.6.5)that, in the presence of complement, depletes alloantigen-specificTs cells but not CTL. This antibody recognizes activated TTscells but not their precursors. In these studies, flow cytometricanalysis demonstrates that 984D4.6.5 reacts with several Tscell hybridomas, cloned Th cell lines and WEHI-3 (a myelomonocytictumor cell line). Reactivity was not detected with BW5147, Thcell hybridomas, cloned Th cells, CTL lines and hybridomas,B cell lines, thymocytes, splenocytes, bone marrow cells nora variety of tumor cells. Among 984D4.6.5 positive lines, expressionis heterogeneous and the number of cells expressing high levelsof the epitope is increased when the hybridomas are maintainedat a relatively high cell density. Neuriminidase and pronasedeplete the epitope recognized by mAb 984D4.6.5. Protein synthesisand glycosylation inhibitors also reduce expression of thisepitope. These observations suggest that the epitope recognizedby 984D4.6.5 is a carbohydrate linked to a polypeptide. Thisantibody was tested by ELISA for binding to a large panel ofcarbohydrates and glycollpids coupled to BSA. The only one thatbound 984D4.6.5 was LS tetrasaccharide c (NeuNAc2-6Galpß1-4GIcNAcß1-3GaIß1-4Glc),an O-linked carbohydrate. Comparative analysis shows that boththe sequence and the linkage of these sugars are essential tothe reactivity with the 984D4.6.5 antibody. This epitope isexpressed by a glycoprotein of-200 kDa, as shown by Westernblots. The identity of this glycoprotein remains to be determined,but indirect evidence suggests that it is not CD45. 相似文献
8.
Manish Kumar Ashutosh Anand Rajeshwari Chatterjee Shubham Sharma Tushar Kanti Maiti Shashi Prakash Dwivedi Ambuj Saxena Changhe Li Elsayed Mohamed Tag Eldin 《Materials》2022,15(17)
The goal of this study was to determine the coefficient of permeability as well as the rate of carbonation of concrete constructed with rice husk ash (RHA) as a partial replacement for cement (i.e., 5%, 10%, and 15%) and two different concentrations of soap solutions (i.e., 1 percent and 2 percent). The microstructural studies of RHA, and carbonated samples have been conducted by using Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) analysis. According to this study, the carbonation depth of concrete made with 1% and 2% soap solution concentration and without rice husk ash decreased by 11.89% and 46.55%, respectively. From the results, it may also be observed that the carbonation depth of concrete made with up to 10% replacement of cement by rice husk ash led to maximum carbonation resistance, while more than 10% replacement of cement showed higher carbonation depth. It is also observed that the coefficient of permeability of concrete with 2% soap solution significantly decreased as compared to the 1% soap solution and control mix. It may be observed from the SEM images that 0% soap solution (M1) concrete has a very rough concrete surface which may indicate more voids. However, 2% soap solution concrete has a much smoother surface, which indicates a smaller number of voids. Furthermore, the SEM images showed that the soap solution helps in filling the voids of concrete which ultimately helps in reduction in permeability. Energy Dispersive X-Ray Analysis (EDX) of concrete with 0% (M1) and 2% (M6) soap solution disclosed that the concrete with 2% soap solution (M6) exhibited more silica element formation than the concrete with no soap solution (M1). 相似文献
9.
Two amide–imine conjugates, viz. 3-methyl-benzoic acid (4-diethylamino-2-hydroxy-benzylidene)-hydrazide (L1) and 3-methyl-benzoic acid (2-hydroxy-naphthalen-1-ylmethylene)-hydrazide (L2), have been prepared and used for a further synthesis of Mo(vi) complexes (M1 and M2, respectively). Single crystal X-ray diffraction analysis confirmed their structures. Interestingly, M1 selectively recognizes Y3+ and Pb2+ at two different wavelengths, whereas M2 selectively interacts with Y3+ with a significantly high binding constant, 1.3 × 105 M−1. The proposed sensing mechanism involves the displacement of Mo(vi) by Y3+/Pb2+ from respective Mo(vi) complexes. The TCSPC experiment also substantiates the “turn-on” fluorescence process. A logic gate has been constructed utilizing the fluorescence recognition of cations by M1. DFT studies corroborated the cation–probe interactions and allowed exploring the orbital energy parameters.Two amide–imine conjugates and their Mo(vi) complexes (M1 and M2) were characterized by single crystal X-ray diffraction analysis. While M1 recognises both Y3+ and Pb2+ at two different wavelengths, M2 recognises only Y3+ with significantly high binding constant. 相似文献
10.