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84.
Pentam Veli Pura Shahul Hameed Muhammed Razia Beevi Rajeev Raghavan Kutty Ranjeet 《Zeitschrift fur angewandte Ichthyologie》2018,34(5):1244-1246
Length‐weight relationships (LWRs) of three needlefishes belonging to the family Belonidae viz., Ablennes hians, Tylosurus crocodilus and Tylosurus acus melanotus were estimated based on samples exploited from a gill‐net fishery in Androth, an island in the Lakshadweep archipelago. The estimated allometric co‐efficient b value ranged from 3.047 (T. acus melanotus) to 3.274 (A. hians), and r2 value ranged from 0.911 (T. acus melanotus) to 0.973 (A. hians). The first estimate of LWR for these three commercially exploited needlefish species from the Lakshadweep islands indicate local populations to be fairly robust and forms a basis for future management of fishing stock in the region. 相似文献
85.
Background
Diverse aquatic microorganisms are capable of colonizing living and non-living surfaces leading to the formation of biofilms. Commonly visualized as a slimy layer, these biofilms are filled with hundreds of other microorganisms compared to free living planktonic cells. Microbial surface colonization and surface-associated metabolic activities also exert several macroscale deleterious effects, including biofouling, biocorrosion and the persistence and transmission of harmful or pathogenic microorganisms and virulence determinants. The present study deals with the isolation and screening of marine bacteria for biofilm formation. The screened isolates were characterized and identified as Pychrobacter celer, Pychrobacter alimentarius and Kocuria rhizophila by 16S rRNA sequencing.Methods
Biofilm forming bacteria were isolated by spread plate technique and subjected to screening by microtiter plate assay. The potent biofilm formers were identified by molecular characterization using 16S rRNA gene sequencing.Results
Twelve bacterial isolates were obtained by pour plate technique and subjected to biofilm assay. Among the 12 isolates three isolates which showed maximum biofilm formation were subjected to molecular characterizationby 16S rRNA gene sequencing method. The isolates were identified as Pychrobacter celer, Pychrobacter alimentarius and Kocuria rhizophila. The EPS produced by the three biofilm forming bacteria was extracted and the protein and carbohydrate content determined.Conclusion
Among the isolates screened, isolate 8 (Kocuria rhizophila) produced maximum protein and carbohydrate which was also in accordance with the results of microtiter plate assay.86.
During germination of the spore of Schizaea pusilla, the first division of the protoplast was perpendicular to the polar axis and resulted in the formation of the rhizoid. The next division parallel to the polar axis of the spore gave rise to the protonemal initial. Following this “Vittaria”-type germination, the protonema that developed was characterized by an extensive branching to produce uniseriate filaments and rhizoidophores. 相似文献
87.
Bharati G Khobarekar Vandana J Vernekar Esakki Prabagaran Vijaya P Raghavan Atmaram H Bandivdekar 《The journal of histochemistry and cytochemistry》2007,55(7):753-762
The 80-kDa human sperm antigen (HSA) has demonstrated to be a promising candidate for development of an antifertility vaccine because it is a sperm-specific, conserved, and immunogenic protein. The present study demonstrates the androgen-regulated expression of 80-kDa HSA in testis and epididymis of rat by immunohistochemistry (IHC), using its specific antibodies. Developmental expression of 80-kDa HSA was investigated on days 10, 20, 40, 60, and 90 of age in the testis and epididymis by IHC, and relative staining intensity was estimated by image analysis using BIOVIS software. On days 10 and 20, no significant staining was observed in the testis and epididymis, whereas it gradually increased from day 40 onwards. The highest staining was seen on day 90 in both testis and epididymis. Gradual increase in expression of 80-kDa HSA after day 40 suggests that it is possibly regulated by androgen. To study the androgen-regulated expression of 80-kDa, adult male rats were treated with 75 mg/kg body weight of ethylene dimethane sulfonate (EDS), which selectively destroys Leydig cells and thus induces complete androgen withdrawal. It was observed that the staining intensity decreased following EDS treatment in rat testis as well as epididymis, and it was regained after supplementation with dihydrotestosterone. Increased expression during sexual maturation at the time of testosterone surge and its regulation by antiandrogen/androgen treatment suggest androgen-dependent expression of 80-kDa HSA in rat testis and epididymis. 相似文献
88.
Zusammenfassung Es wurden Pollenschläuche vonNemophila insignis untersucht, die auf 15% igem Zuckeragar gewachsen waren.Der vegetative Kern war bei geeigneter Färbung stets sichtbar, und zwar meistens als ein sehr lang ausgezogener, fadenförmiger Körper. Auch nach 72stündiger Kulturdauer waren Degenerationserscheinungen an ihm nicht zu bemerken.Der generative Kern liegt in einer spindelförmigen oder ellipsoidischen Zelle, deren Plasma mit Hämatoxylin nicht gefärbt wird.Die Teilung des generativen Kernes verläuft unregelmäßig: Es tritt wohl eine Teilung der Chromosomen ein, aber die Tochterchromosomen verteilen sich nicht auf zwei Pole, so daß es zur Bildung eines Restitutionskernes kommt.Es wird die Annahme gemacht, daß diese Restitutionskernbildung eine Folge ungünstiger Kulturerscheinungen ist.Mit 5 Textabbildungen.Der letztgenannte Verfasser, der im Sommer 1937 für einige Zeit im Botanischen Institut in Kiel freundliche Aufnahme fand, möchte die Gelegenheit benutzen, um Herrn ProfessorTischler für seine liebenswürdige Gastfreundschaft und die Überlassung eines Arbeitsplatzes auch an dieser Stelle zu danken. 相似文献
89.
Molten globule-like intermediates have been shown to occur during protein folding and are thought to be involved in protein translocation and membrane insertion. However, the determinants of molten globule stability and the extent of specific packing in molten globules is currently unclear. Using far- and near-UV CD and intrinsic and ANS fluorescence, we show that four periplasmic binding proteins (LBP, LIVBP, MBP, and RBP) form molten globules at acidic pH values ranging from 3.0 to 3.4. Only two of these (LBP and LIVBP) have similar sequences, but all four proteins adopt similar three-dimensional structures. We found that each of the four molten globules binds to its corresponding ligand without conversion to the native state. Ligand binding affinity measured by isothermal titration calorimetry for the molten globule state of LIVBP was found to be comparable to that of the corresponding native state, whereas for LBP, MBP, and RBP, the molten globules bound ligand with approximately 5-30-fold lower affinity than the corresponding native states. All four molten globule states exhibited cooperative thermal unfolding assayed by DSC. Estimated values of DeltaCp of unfolding show that these molten globule states contain 28-67% of buried surface area relative to the native states. The data suggest that molten globules of these periplasmic binding proteins retain a considerable degree of long range order. The ability of these sequentially unrelated proteins to form highly ordered molten globules may be related to their large size as well as an intrinsic property of periplasmic binding protein folds. 相似文献
90.
G A Ameer S Raghavan R Sasisekharan W Harmon C L Cooney R Langer 《Biotechnology and bioengineering》1999,63(5):618-624
The development of a safe and efficient bioreactor design has remained a challenge for the clinical application of immobilized enzymes. Specifically, the use of immobilized heparinase I has been the target of many studies to make heparin anticoagulation therapy safer for the critically ill patient with kidney failure or heart disease. We have investigated the use of Taylor-Couette flow for a novel type of bioreactor. In a previous study, we showed that the fluidization of agarose immobilized heparinase within Taylor vortices in whole blood can lead to extensive blood damage in the form of cell depletion and hemolysis. Based on these findings, we designed and developed a reactor, referred to as vortex-flow plasmapheretic reactor (VFPR), that incorporated plasmapheresis and fluidization of the agarose in the reactive compartment, separate from the whole-blood path. In the present study, immobilized heparinase I was tested as a means of achieving regional heparinization of a closed circuit. This is a method in which heparin is infused into the extracorporeal circuit predialyzer and neutralized postdialyzer. Saline studies were performed with an immobilized heparinase I-packed bed and with the VFPR. An in vitro feasibility study was performed with the VFPR using human blood. The VFPR achieved heparin conversions of 44 +/- 0.5% and 34 +/- 2% in saline and blood, respectively. In addition, the VFPR caused no blood damage. We report a novel method to achieve fluidization which depended on secondary, circumferencial flow, and was independent of the primary flow through the device. 相似文献