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1.
The Hoechst dye staining method has been successfully applied to the central nervous system in mammals and its use has been demonstrated in intracerebral transplantation. The technique is rapid, simple and based on intrinsic nuclear properties. It was found to be permanent and valid whatever the animal strains or ages, allowing the distinction of rat cells from those of mouse, studied either separately or in a cross-transplantation model. It permitted the detection of grafted cells in the area of transplantation and the observation of early dispersion around the implantation site. Moreover, it can be combined with immunohistochemistry as demonstrated by a myelin marker in a relevant model. Immunodetection can thus help to directly observe grafted cells, at distance from the locus of transplantation, confirming their presence in the graft-type myelin patches.
Because of its rapid performance, this technique can be used systematically after transplantation to check for the presence of grafted cells in the host. 相似文献
Because of its rapid performance, this technique can be used systematically after transplantation to check for the presence of grafted cells in the host. 相似文献
2.
采用TUNEL染色及免疫组织化学技术对光化学法脑缺血后细胞凋亡及其相关基因bcl-2表达的变化进行了研究。结果发现,缺血后12h,损伤侧皮层缺血区内凋亡细胞数及bcl-2免疫反应阳性细胞数明显增加,一直持续至缺血后72h;并呈现下列时程变化:在缺血后3h每张切片上几乎无凋亡细胞出现,以后逐渐增加,缺血后12h达到峰值,缺血后24h和缺血后72h逐渐减少,但仍高于假手术组水平。凋亡相关基因bcl-2的表达在缺血后3h以前不明显,缺血后12h逐渐增加,缺血后24h最多,以后逐渐下降。上述结果提示,缺血后凋亡细胞的时程变化可能与缺血后梗塞灶的发生和发展有关,而bcl-2表达的变化可能与抑制细胞凋亡、发挥内源性细胞保护作用有关。 相似文献
3.
4.
Paloma Rocha Arakaki Paula Andrea Borges Salgado Joo Diego de Agostini Losano Marcel Henrique Blank Marcílio Nichi Ricardo Jos Garcia Pereira 《American journal of primatology》2019,81(8)
The golden‐headed lion tamarin (Leontopithecus chrysomelas) is an endangered species endemic to Brazil's Atlantic Forest, a shrinking biodiversity hotspot. As in other Neotropical primates, its semen characteristics and freezability are poorly studied. Hence, reproductive technologies for callitrichids would greatly benefit from reliable methods of semen analysis. In a bid to promote reproductive research in tamarins, we validated simple and inexpensive sperm function tests that can be used to monitor sperm‐egg binding, plasma membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. Ejaculates from adult males were individually diluted and divided into control and damage‐induced aliquots, and then samples comprising assorted amounts of damaged spermatozoa were examined by organelle‐specific tests. Our findings showed that sperm‐binding in chicken egg perivitelline membrane (EPM) positively correlated with the number of spermatozoa injured by snap‐freezing. Eosin‐nigrosin (EN) and propidium iodide readings were correlated with each other, and both provided robust measurements of plasma membrane integrity. A high correlation between expected and measured amounts of acrosome‐intact spermatozoa was found using Fast Green‐Rose Bengal (FG‐RB), Coomassie Blue (CB), and FITC‐PSA stains, and all three methods exhibited comparable results. Likewise, different percentages of UV‐irradiated spermatozoa were accurately assessed for DNA integrity by Toluidine Blue (TB) and sperm chromatin dispersion (SCD) tests. Comparisons between 3,3′‐diaminobenzidine (DAB) and JC‐1 stains also indicated the reliability of the former assay to ascertain gradual increases in spermatozoa with greater mitochondrial function. These data confirmed that different parts of the tamarin spermatozoa can be simply and consistently evaluated by EPM, EN, FG‐RB, CB, TB, and DAB protocols. 相似文献
5.
When intact Toxoplasma trophozoites were stained with isotonic alkaline methylene blue solution, the organelles rich in nucleic acid, i.e., nucleus, free and membrane-bound ribosomes appeared as electron dense areas. When the parasites were incubated with the anti-Toxoplasma antibody and the accessory factor, swelling of the surface membrane occurred first, followed by destruction of the inner structures. In the dye test positive parasites, there were no definite organelles recognizable, as there were in the intact parasites. By the negative staining method, holes (defects) with dark central portions were observed on the surface of the parasites treated with the antibody and the accessory factor, the diameter of the holes measuring about 10–11 nm. These holes, which tended to occur in clusters, were each surrounded by a clear ring. 相似文献
6.
J. P. DUBEY 《The Journal of eukaryotic microbiology》1997,44(6):592-602
ABSTRACT. The development of Toxoplasma gondii was studied in mice fed bradyzoites. At one hour after oral inoculation (HAI), bradyzoites were found in cells of the surface epithelium and the lamina propria of the small intestine, primarily the ileum. Division into two tachyzoites was first observed at 18 HA1 in the intestine. At 24 HAI, organisms were also seen in mesenteric lymph nodes. Organisms were first detected in the brain at six days after oral inoculation with bradyzoites (DAI) but not consistently until 10 DAI. Immunohistochemical staining with bradyzoite specific (BAG-5 antigen) anti-serum showed that bradyzoites retained their BAG-5 reactivity even after the first division into two tachyzoites in the intestine at 18 HAL BAG-5 positive organisms were not seen 2–5 DAI. BAG-5 antigens reappeared in T. gondii at 6 DAI. Whole mice and individual tissues of mice fed bradyzoites were bioassayed in cats and mice for the presence of bradyzoites. Feces of cats fed murine tissues were examined for oocyst shedding for short prepatent periods. Bradyzoites were present in the intestines of mice up to 12 HA1 but not at 18 HAI, and tachyzoites and not bradyzoites disseminated to other tissues from the intestine. Bradyzoites were again detected 6 DAI. Using the mouse bioassay, T. gondii was first detected in peripheral blood at 24 HA1 and more consistently at 48 HAL Using a pepsin-digestion procedure and mouse bioassay, organisms were demonstrated in many tissues of mice 15 and 49 DAI. 相似文献
7.
Zandra M. S. Sigvardt Katrine Worsaae Sukonthip Savatenalinton Alexandra Kerbl Jørgen Olesen 《Journal of morphology》2020,281(10):1241-1259
Great diversity is found in morphology and functionality of arthropod appendages, both along the body axis of individual animals and between different life-cycle stages. Despite many branchiopod crustaceans being well known for displaying a relatively simple arrangement of many serially post-maxillary appendages (trunk limbs), this taxon also shows an often unappreciated large variation in appendage morphology. Diplostracan branchiopods exhibit generally a division of labor into locomotory antennae and feeding/filtratory post-maxillary appendages (trunk limbs). We here study the functionality and morphology of the swimming antennae and feeding appendages in clam shrimps and cladocerans and analyze the findings in an evolutionary context (e.g., possible progenetic origin of Cladocera). We focus on Cyclestheria hislopi (Cyclestherida), sister species to Cladocera and exhibiting many “large” branchiopod characters (e.g., many serially similar appendages), and Sida crystallina (Cladocera, Ctenopoda), which likely exhibits plesiomorphic cladoceran traits (e.g., six pairs of serially similar appendages). We combine (semi-)high-speed recordings of behavior with confocal laser scanning microscopy analyses of musculature to infer functionality and homologies of locomotory and filtratory appendages in the two groups. Our morphological study shows that the musculature in all trunk limbs (irrespective of limb size) of both C. hislopi and S. crystallina comprises overall similar muscle groups in largely corresponding arrangements. Some differences between C. hislopi and S. crystallina, such as fewer trunk limbs and antennal segments in the latter, may reflect a progenetic origin of Cladocera. Other differences seem related to the appearance of a specialized type of swimming and feeding in Cladocera, where the anterior locomotory system (antennae) and the posterior feeding system (trunk limbs) have become fully separated functionally from each other. This separation is likely one explanation for the omnipresence of cladocerans, which have conquered both freshwater and marine free water masses and a number of other habitats. 相似文献
8.
The topography of long hair sensilla on the coxae of walking legs and pedipalps of the scorpionHeterometrus fulvipes is described. Identified long hair sensilla are cobalt filled, and central projections of sensory fibres are reported for
the first time in the suboesophageal ganglion of this scorpion. The afferent fibres arising from each long hair sensilla segregate
into ventral, dorsomedial and dorsal tracts upon their entry into the suboesophageal ganglion. These transverse tracts bifurcate
towards the middle of the leg neuromere and form three ipsilateral, plurisegrnental, longitudinal sensory pathways. Filling
a pair of bilaterally distributed long hair sensilla shows bilaterally arranged longitudinal afferent tracts interconnected
by distinct transverse commissures. Similar patterns of sensory projections are observed when filling homologous hairs on
other legs and pedipalps. Numerous fine collaterals arise from the longitudinal sensory trancts that subdivide and end in
small blebs presumed to be presynaptic endings. The dorsal and dorsomedial longitudinal tracts and their respective commissures
are in close association with the dendritic arborisations of pedipalpal and leg motor neurons, suggesting direct contact between
them. The probable functions of these multisegmental hair afferent pathways are discussed. 相似文献
9.
Members of the casein kinase 1 (CK1) family are evolutionarily conserved eukaryotic protein kinases involved in various cellular, physiological, and developmental processes in yeast. However, the biological roles of CK1 members in plants are poorly understood. Here, we report that an Arabidopsis CK1 member named casein kinase 1-like 8 (CKL8) was ubiquitously expressed in all plant organs, mainly in the stems of seedlings according to quantitative real-time PCR. Western blotting showed a remarkable expression of the AtCKL8 gene in transgenic plants induced by high salinity. A histochemical assay of AtCKL8 promoter::GUS expression revealed that the AtCKL8 promoter is very active in both seedlings and adult plants subjected to the salinity stress, while no GUS activity was detectable in all the transgenic plants grown under normal conditions. In a subcellular distribution analysis, the AtCKL8-GFP fusion protein was localized mainly in the cell membrane. AtCKL8-overexpressing transgenic plants showed an insensitivity to high salinity and an early flowering phenotype. Overall, these findings suggest that AtCKL8 plays a positive role in NaCl signaling and improves salt stress tolerance in transgenic Arabidopsis. 相似文献
10.
Yeon-Jin Chu Jin-Young Lee So-Ra Shin Geun-Joong Kim 《Indian journal of microbiology》2015,55(4):460-463
Ammonia oxidizing archaea (AOA) are predominantly found and closely linked with geochemical cycling of nitrogen in non-extreme habitats. However, these strains have mainly been investigated using liquid cultures of enriched cells. Here, we provide an agar stab as a simple and reliable means of cultivating and maintaining AOA. 相似文献