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1.
In many mammals, sperm associations had been observed, but not in the mouse. In this work, mouse sperm rosettes are morphologically described inside the epididymis and during its dissolution in a culture medium. Also characterized are the saccharides present in the linking material. Sperm association and other epididymal actions are supported by sperm during epididymal transit and are verified at the caudal region, suggesting a relation between epididymal transit and sperm maturation. In drops of epididymal content obtained from distal (cauda), but not from proximal (caput and corpus) regions; dissolved in culture medium, rosettes appear to be 10 to 15 motile sperm joined by their heads. After 3 min, sperm progressively detach, disassembling the rosette. These structures are studied by several techniques, including optic, electronic (scanning electron microscopy and transmission electron microscopy), and video microscopy. At the ultrastructural level, a dense network of electron‐dense material was observed between sperm heads, joining them. Based on previous works in rat, several lectins were used to characterize the type of saccharides present in this linking material. To avoid the contact between sperm and epididymal fluid from distal region—that probably exerts an influence on sperm association—a ligature was placed between caput and corpus. This epididymal content isolated from caput did not display any rosettes after 28 days. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
2.
Secretion in neutrophils is thought to be regulated in different ways for the different granule types. Specific granules are endowed with proteins which are related to docking and fusion events and are absent on azurophilic granules. Furthermore, even if secretion of content from all neutrophil granules is a Ca(2+)-dependent process, a higher concentration of cytosolic calcium is required for azurophilic than for specific granule secretion. In this paper we show that human neutrophils and promyelocitic cells express neuronal calcium sensor-1 (NCS-1), a calcium binding protein involved in exocytosis in various cell types. Both mRNA and protein were found in mature cells and precursors. NCS-1 is shown to be mainly associated with azurophilic granules and, therefore could play an instrumental role in the calcium-dependent secretion of azurophilic granules.  相似文献   
3.
Morphine and methadone impact on human phagocytic physiology   总被引:3,自引:0,他引:3  
Human subjects submitted to treatment with morphine show a severe depression of phagocytosis, killing properties and superoxide production both of their polymorphonuclear leukocytes and monocytes. Polymorphonuclear leukocyte adherence, chemotaxis, random migration, myeloperoxidase content, lysozyme content and lymphocyte Rosette E formation were poorly influenced. Methadone-treated subjects show a similar effect at phagocytic level but far less evident. These results confirm those previously found in animals and reinforce the evidence of a depressive role of morphine on phagocytic physiology.  相似文献   
4.
Abstract

Monitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms.  相似文献   
5.
BACKGROUND: Although allergic mechanisms appear to be important, the pathogenesis of both extrinsic and intrinsic forms of atopic dermatitis (AD) is unknown. METHODS: We compared the cytokine production of peripheral blood mononuclear cells of extrinsic AD (EAD) and intrinsic AD (IAD) patients and normal control individuals after stimulation with anti-CD3 and/or anti-CD28 monoclonal antibodies (mAbs) in the presence or absence of anti-CD2-blocking mAb. The cytokine production was measured by immunoassays in supernatants of 24-hour cultures. RESULTS: EAD patients showed a decreased capacity to synthesize interferon gamma and granulocyte-macrophage colony-stimulating factor upon anti-CD3 mAb stimulation as compared with IAD patients. Both EAD and IAD patients demonstrated an increased production of interleukin (IL)-5 and IL-13. As expected, interferon gamma, granulocyte-macrophage colony-stimulating factor, and IL-5 levels were reduced in the presence of anti-CD2-blocking mAbs. CD28 costimulation restored the release in cultures with anti-CD2 mAbs added, suggesting that CD2 and CD28 have redundant functions in T cell activation and subsequent cytokine production. Strikingly, the IL-13 production was not blocked by anti-CD2 mAbs and also not increased by agonistic anti-CD28 mAb, in particular within the EAD patient group. CONCLUSION: The signalling pathway initiated by the T cell receptor complex leading to increased IL-13 production in AD patients appears to be highly sensitive and is largely independent on CD2 costimulatory signals.  相似文献   
6.
A group of 45 children affected with Coeliac Disease (CD) was typed for HLA-A, B, C, D, and DR specificities. The most significant associations were found with two alleles of the D series, with both cellular and serological typing. It is suggested that the susceptibility to CD is determined by two different genes within the HLA region, the first in common with organ-specific autoimmune diseases and associated with DW3, the second possibly specific for CD and associated with Dw7.  相似文献   
7.
Lasers in Medical Science - This study compared the effects of LED therapy associated with occlusal splint (OS) on the signs and symptoms of temporomandibular disorder (TMD). In this randomized,...  相似文献   
8.
We have previously found that a short-term treatment with high doses of ipriflavone increased bone density and improved the biomechanical properties of adult male rat bones, without altering their mineral composition. To determine whether this effect can be associated with alterations of bone crystal structure, we have performed X-ray diffraction analysis of bones obtained from rats treated with ipriflavone at doses that were effective in inducing favorable changes on bone density and biomechanics. Eighteen-week-old male Sprague Dawley rats were treated by oral route with either ipriflavone (200 or 400 mg/kg/day), or its vehicle for 12 weeks. The treatment was well tolerated and body weight increased to the same extent in all animals. As a measure of bone crystallinity, we examined the (310) and (002) reflections of the X-ray diffraction patterns, corresponding to the directions perpendicular and parallel to the c-axis of the crystals, respectively. No major differences were observed between ipriflavone-treated and control animals for the broadening parameter 1/2 for (310) and (002) peaks, as well as for lattice parameters. Therefore, a 12-week treatment with ipriflavone at high doses does not induce significant modifications of bone crystallinity. Thus. the positive effect of ipriflavone on bone mineral density appears to be associated with an increased apatite crystal formation rather than an increase of crystal size. These results provide further evidence for the safety and usefulness of ipriflavone in the treatment of osteoporotic syndromes.  相似文献   
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