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161.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
162.
Kirton CM Laukkanen ML Nieminen A Merinen M Stolen CM Armour K Smith DJ Salmi M Jalkanen S Clark MR 《European journal of immunology》2005,35(11):3119-3130
Human vascular adhesion protein-1 (VAP-1) is a homodimeric 170-kDa sialoglycoprotein that is expressed on the surface of endothelial cells and functions as a semicarbazide-sensitive amine oxidase and as an adhesion molecule. Blockade of VAP-1 has been shown to reduce leukocyte adhesion and transmigration in in vivo and in vitro models, suggesting that VAP-1 is a potential target for anti-inflammatory therapy. In this study we have constructed mouse-human chimeric antibodies by genetic engineering in order to circumvent the potential problems involved in using murine antibodies in man. Our chimeric anti-VAP-1 antibodies, which were designed to lack Fc-dependent effector functions, bound specifically to cell surface-expressed recombinant human VAP-1 and recognized VAP-1 in different cell types in tonsil. Furthermore, the chimeric antibodies prevented leukocyte adhesion and transmigration in vitro and in vivo. Hence, these chimeric antibodies have the potential to be used as a new anti-inflammatory therapy. 相似文献
163.
Benjamin Kligler Mary Koithan Victoria Maizes Meg Hayes Craig Schneider Patricia Lebensohn Susan Hadley 《BMC medical education》2007,7(1):7
Background
As more integrative medicine educational content is integrated into conventional family medicine teaching, the need for effective evaluation strategies grows. Through the Integrative Family Medicine program, a six site pilot program of a four year residency training model combining integrative medicine and family medicine training, we have developed and tested a set of competency-based evaluation tools to assess residents' skills in integrative medicine history-taking and treatment planning. This paper presents the results from the implementation of direct observation and treatment plan evaluation tools, as well as the results of two Objective Structured Clinical Examinations (OSCEs) developed for the program. 相似文献164.
Clinical findings and structural alterations in the kidneys of 6 patients with sarcoidosis and an associated glomerulonephritis are described. Five of the 6 patients manifested the nephrotic syndrome during some phase of their illness. Additional clinical evidence of renal disease included persistent microscopic hematuria (5 patients), hypertension (4 patients) and progressive renal failure (3 patients). Glomerular pathology varied and included proliferative glomerulonephritis (3 patients), membranous glomerulonephritis (1 patient), and chronic glomerulonephritis (2 patients). In 2 patients sequential examination of the kidney was possible, with renal biopsies preceding autopsy examination by 3 and 6 years, respectively. Glomerular pathology had progressed in severity in each case. Immunofluorescent studies in 2 patients revealed patterns of glomerular antibody localization consistent with immune complex disease. Electron microscopic studies of 1 revealed membranous changes characterized by electron-dense subepithelial and intramembranous deposits. Totally unexpected were virus-like intraendothelial structures in the glomeruli identical to those previously reported in systemic lupus erythematosus. Since current evidence suggests that the pathogenesis of both membranous and proliferative types of glomerulonephritis is immunologic, it should not be surprising that sarcoidosis, a disease which quite possibly results from an immune response to a disseminated antigen(s), should occasionally include glomerulonephritis as a part of its histologic expression. 相似文献
165.
Popat KC Leary Swan EE Mukhatyar V Chatvanichkul KI Mor GK Grimes CA Desai TA 《Biomaterials》2005,26(22):4516-4522
A major goal of bone tissue engineering is to design better scaffold configuration and materials to better control osteoblast behavior. Nanoporous architecture has been shown to significantly affect cellular response. In this work, nanoporous alumina membranes were fabricated by a two-step anodization method to investigate bone cell response. Osteoblasts were seeded on nanoporous alumina membranes to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard MTT assay and cell counting. The total protein content was measured after cell lysis using the BCA assay. Matrix production was characterized in terms of surface concentrations of calcium and phosphorous, components of bone matrix, using X-ray photoelectron spectroscopy (XPS). The results from nanoporous alumina membranes were compared with those of amorphous alumina, aluminum, commercially available ANOPORE and glass. Results indicate improved osteoblast adhesion and proliferation and increased matrix production after 4 weeks of study. 相似文献
166.
167.
Induced recruitment of NK cells to lymph nodes provides IFN-gamma for T(H)1 priming 总被引:13,自引:0,他引:13
Martín-Fontecha A Thomsen LL Brett S Gerard C Lipp M Lanzavecchia A Sallusto F 《Nature immunology》2004,5(12):1260-1265
Naive T cells are stimulated by antigen-presenting dendritic cells (DCs) in secondary lymphoid organs, but whether other types of cell participate in T cell priming is unclear. Here we show in mice that natural killer (NK) cells, which are normally excluded from lymph nodes, are rapidly recruited in a CCR7-independent, CXCR3-dependent manner to lymph nodes on stimulation by the injection of mature DCs. Recruitment of NK cells is also induced by some, but not all, adjuvants and correlates with the induction of T helper cell type 1 (T(H)1) responses. NK cell depletion and reconstitution experiments show that NK cells provide an early source of interferon-gamma (IFN-gamma) that is necessary for T(H)1 polarization. Taken together, our results identify an induced pathway of NK cell migration in antigen-stimulated lymph nodes and a mechanism by which some adjuvants may facilitate T(H)1 responses. 相似文献
168.
The serine/threonine kinase Pim-2 is a transcriptionally regulated apoptotic inhibitor 总被引:13,自引:0,他引:13
Fox CJ Hammerman PS Cinalli RM Master SR Chodosh LA Thompson CB 《Genes & development》2003,17(15):1841-1854
169.
Piyush Patel George Philip William Yang Robert Call Friedrich Horak Craig LaForce Leen Gilles Graigory C Garrett S Balachandra Dass Barbara A Knorr Theodore F Reiss 《Annals of allergy, asthma & immunology》2005,95(6):551-557
BACKGROUND: Perennial allergic rhinitis (PAR) is a persistent allergic inflammation of the upper respiratory tract due to year-round allergen exposure. OBJECTIVE: To evaluate the leukotriene receptor antagonist montelukast for the treatment of PAR. METHODS: Protocol 265 was a 2-arm study performed during the winter. After a placebo run-in period, adults with perennial allergen sensitivity and active symptoms of PAR were randomized to receive 10 mg of montelukast (n=1002) or placebo (n=990) once daily during a 6-week, double-blind, active-treatment period. The primary end point was the daytime nasal symptoms score, defined as the average of scores for nasal congestion, rhinorrhea, and sneezing rated daily by patients. RESULTS: Statistically significant improvements in PAR symptoms were seen in patients treated with montelukast. Their daytime nasal symptoms scores were reduced during treatment compared with those of the placebo group: the difference between treatments in least squares mean change from baseline was -0.08 (95% confidence interval [CI], -0.12 to -0.04; P < .001). Montelukast treatment also improved global evaluations of allergic rhinitis by patients and Rhinoconjunctivitis Quality of Life Questionnaire scores: differences vs the placebo group were -0.15 (95% CI, -0.27 to -0.04; P < .01) and -0.15 (95% CI, -0.24 to -0.06; P < .001), respectively. Other end points that showed statistically significant improvement with montelukast treatment were nighttime symptoms and each of the 4 nasal symptoms (congestion, rhinorrhea, sneezing, and itching). The treatment effects of montelukast were stable and persistent during the entire 6 weeks of treatment. CONCLUSION: Montelukast provided statistically significant relief of PAR symptoms during 6 weeks of treatment. 相似文献
170.