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901.
Roberto Cevenini Alessandra Moroni Vittorio Sambri Silvio Perini Michele La Placa 《FEMS microbiology letters》1989,47(8-9):259-264
Abstract Two enzyme-linked immunosorbent assays (ELISA) using highly purified elementary bodies (EB) of Chlamydia psittaci A/22 strain (ovine) or 6BC strain (psittacine) were set up for the detection of antichlamydial antibodies in sheep. No significant differences were observed between the two ELISAs, whereas these tests proved to be more sensitive than complement fixation test and showed a good correlation ( r = 0.75) with immunofluorescence assay. The periodate treatment of chlamydial antigens modified the results of serological responses studied by ELISA, depending on the sera. The average reduction of ELISA values by periodate was 28%, ranging between 5% and 65%. The immunoblot analysis of sheep sera showed high cross reactivity between the polypeptides of A/22 and 6BC strains. However, some differences were observed. The major outer membrane protein (MOMP) of 6BC strain was recognized at different molecular weight position (40 000 kDa) in comparison with the MOMP of A/22 strain (38 000 kDa). In addition, a clear band of 97 000 kDa was detected by all sheep sera tested with A/22 strain. This band was undetectable in the blots performed with 6BC strain. 相似文献
902.
903.
Wanessa Santana Simone S. C. de Oliveira Mariana H. Ramos André L. S. Santos Silvio S. Dolabella Eliana B. Souto Patrícia Severino Sona Jain 《化学与生物多样性》2021,18(9):e2100336
Leishmaniasis is a group of tropical diseases caused by parasitic protozoa belonging to the genus Leishmania. The disease is categorized in cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL), and visceral leishmaniasis (VL). The conventional treatment is complex and can present high toxicity and therapeutic failures. Thus, there is a continuing need to develop new treatments. In this review, we focus on the novel molecules described in the literature with potential leishmanicidal activity, categorizing them in pre-clinical (in vitro, in vivo), drug repurposing and clinical research. 相似文献
904.
Sergio Tamburini Pietro A Vigato Silvio Aime Mauro Andrea Cremonini 《Inorganica chimica acta》2004,357(5):1374-1380
Quantitative 2H NMR analysis at the natural abundance represents a well-recognized and efficient method for the identification of the origin of ethanol from different sources. An intrinsic limitation of the protocol used is the long time required, about 8 h, because of the long T1 values of the 2H resonances. In this work we propose the use a paramagnetic relaxation agent that significantly catalyzes the relaxation times and reduces the total time of the analysis. This agent is the macrocyclic Schiff base complex [Gd(H2L)(H2O)3(EtOH)](Cl)3 · 2 EtOH (H2L is the [1 + 1] macrocycle derived from the condensation of 3,3′-(3-oxapentane-1,5-diyldioxy)bis(2-hydroxybenzaldehyde) with 1,5-diamino-3-azamethylpentane), which is highly stable and soluble in the alcoholic solution used. Elemental analysis, IR and mass spectrometry have characterized this complex. The homogeneity of the complex and the correct Gd:Cl=1:3 ratio was established by SEM-EDS measurements. Further characterization of the paramagnetic complex has been achieved by measuring the magnetic field dependence of the 1H longitudinal nuclear magnetic relaxation time of a 1 mM solution in CH3OD with a field-cycling relaxometer. The GdIII ion accommodates up to four methanol molecules in its inner coordination sphere, whose rapid exchange with the bulk provides an efficient relaxation mechanism. The addition of about 37 mg of the complex to a solution of ethanol (3.0 g) and tetramethylurea (TMU) (1.5 g) results in the reduction of the experimental time of more than 50% with a S/N ratio compatible with that required for this application. 相似文献
905.
Cecília Craveiro Roberta Soares Hildemário Castro-Neto Emanuell F. Silva Andrey Soares Paulo G. V. de Oliveira Evelyn Gonzalez Silvio Peixoto 《Acta zoologica》2023,104(4):506-515
We observed the presence of follicular cells (FC) in the ovaries of Penaeus subtilis (n = 1198), which led us to classify the development of germ cells into six phases: oogonia, previtellogenic oocytes, primary and secondary vitellogenic oocytes, mature oocytes and atretic oocytes. The FC changes their shape according to the development of germ cells and showed a different distribution along the ovary, which allowed differentiating vitellogenic oocytes into primary and secondary. We also observed that the postovulatory follicles (POF) are composed of follicular cells. The presence of POF in penaeids ovaries is rarely reported, but allows the differentiation between spent and resting stages, commonly grouped in reproductive biology research. Furthermore, observation of ovarian lining was useful to differentiate immature females from females that had spawned at least once. Thus, ovarian development was classified into six stages: immature, early developing, advanced developing, ripe, spent and resting. The distribution and shape variations of FC, ovarian lining features and presence of POF were considered crucial for the classification of ovarian maturation stages. The methods developed here may improve estimates of their reproductive cycle, size at first maturity and spawning season, which are important variables in future studies of the reproductive dynamics. 相似文献
906.
907.
Diogo B. Provete Lilian Franco‐Belussi Lia R. De Souza Santos Rodrigo Zieri Rafaela M. Moresco Itamar A. Martins Silvio C. De Almeida Classius De Oliveira 《Zoologica scripta》2012,41(6):547-556
Provete, D. B, Franco‐Belussi, L., de Souza Santos, L. R., Zieri, R., Moresco, R. M., Martins, I. A., de Almeida, S. C., & de Oliveira, C. (2012). Phylogenetic signal and variation of visceral pigmentation in eight anuran families. —Zoologica Scripta, 41, 547‐556. Visceral pigmentation is found in several organs and structures of ectothermic animals, comprising the extracutaneous pigmentary system. Its function is not well defined, although it is known that melanin is produced and stored inside pigmented cells. Previous studies demonstrated that the distribution of visceral pigmentation is neither homogeneous among organs among anuran species. We described the diversity of visceral pigmentation in 12 organs/structures from 32 anuran species belonging to eight families in a phylogenetic context. We also determined in which node(s) of the phylogeny there is more variation in the pigmentation and whether this variation has phylogenetic signal. The visceral pigment cells in organs and structures of the abdominal cavity varied among genera. All species had pigmentation in the urogenital and cardiorespiratory systems, whereas the stomach lacks pigmentation in all species. We also found a phylogenetic signal for pigmentation in all organs and structures taken together, besides heart, testes, lumbar parietal peritoneum and lumbar nerve plexus when considered separately. Overall, considering all organs, the highest diversity of categories of pigmentation was found in the nodes corresponding to Cruciabatrachia and Athesphatanura. This study constitutes the first step towards understanding the evolution of visceral pigmentation in anurans. 相似文献
908.
Mauro DiNuzzo Silvia Mangia Bruno Maraviglia Federico Giove 《Neurochemical research》2012,37(11):2432-2438
Energy homeostasis in the brain is maintained by oxidative metabolism of glucose, primarily to fulfil the energy demand associated with ionic movements in neurons and astrocytes. In this contribution we review the experimental evidence that grounds a specific role of glycogen metabolism in supporting the functional energetic needs of astrocytes during the removal of extracellular potassium. Based on theoretical considerations, we further discuss the hypothesis that the mobilization of glycogen in astrocytes serves the purpose to enhance the availability of glucose for neuronal glycolytic and oxidative metabolism at the onset of stimulation. Finally, we provide an evolutionary perspective for explaining the selection of glycogen as carbohydrate reserve in the energy-sensing machinery of cell metabolism. 相似文献
909.
Animal viruses, predominantly enteroviruses, were detected in shallow water at bottom depths and in clastic marine sediments. Viruses accumulated in sandy and slimy deposits of the sea bottom near the shore and could be easily released into water by means of simple mechanical shaking. 相似文献
910.
This work consists of an extensive study of soil properties and floristic composition of the Paraguayan Chacoan forests. The role of the soil factors was determined conditioning the classical landscape differentiation between the dry western Chaco and the wet eastern Chaco. Soil horizon A best explains the previous classification of the forests. It highlights the soil differences between the eastern and western Chaco. CCA ordination including all forest, soil and geographical factors primarily arranged the plant associations along a W-E gradient. A significant relationship was found between the composition of the northern Paraguayan Chaco forest and geographic longitude, drainage and altitude. CCA ordination focusing on alluvial forests and soil features identified clay content as the primary soil factor discriminating forest types; it also underlined the importance of cation exchange and the content of exchange bases in the soil for differentiating dry and wet Chacoan forests. 相似文献