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1.
PADGEM (GMP140) is a component of Weibel-Palade bodies of human endothelial cells 总被引:65,自引:10,他引:55
PADGEM protein (PADGEM), also known as GMP140, is a platelet alpha- granule membrane protein that is translocated to the external membrane after platelet activation. Although the biosynthesis of this protein was originally thought to be confined to megakaryocytes, the synthesis of PADGEM in endothelial cells was recently demonstrated (McEver et al: Blood 70:1974a, 1987). We now describe the subcellular localization of this protein in endothelial cells. Immunofluorescence staining of permeabilized human umbilical vein endothelial cells with KC4, a well characterized monoclonal antibody to PADGEM, showed positively stained elongated structures similar in distribution and shape to Weibel-Palade bodies. Their identity as Weibel-Palade bodies was confirmed by double label immunofluorescence using KC4 and a polyclonal antiserum to von Willebrand factor (vWf), a protein known to be specifically stored in these organelles. All Weibel-Palade bodies were found to contain PADGEM. In contrast to strong perinuclear staining produced with anti- vWf antibodies, no significant perinuclear staining was obtained with KC4, indicating that relatively little PADGEM is present in the endoplasmic reticulum and in the Golgi apparatus. In endothelial cells treated with secretagogues that stimulate vWf release the elongated structures positive for PADGEM disappeared, further identifying these structures as Weibel-Palade bodies. This observation extends the parallels between Weibel-Palade bodies and alpha-granules and suggests a possible functional association between vWf and PADGEM. 相似文献
2.
Most of the work of host defense has been carried out in mixed patient populations. It is now clear that elective preoperative surgical patients have totally different host defense capabilities as compared to posttrauma patients or those suffering from peritonitis. Specific cell-mediated immune studies need to be repeated in these 2 patient groups as well. What will contribute clinical relevance to these studies will be the means to correct the defects. If these defects or—more correctly termed—abnormalities of host defense are, indeed, important and contribute to an increased sepsis rate and mortality from sepsis in affected patients, then correcting them should reduce these complications. This hypothesis can only be tested when such means become available. The issues of most interest in the next few years will be the significance of serum albumin in host outcome, the role of immunomodulators, the involvement of cytokines in the overall process of host defense, and the use of specific nutritional support regimens targeted to the immune system.
Supported in part by grants from the Medical Research Council of Canada and the Fonds de recherche de Santé. 相似文献
Resumen La mayor parte del trabajo sobre los mecanismos de defensa del huésped ha sido realizada en poblaciones mixtas de pacientes. Actualmente aparece claro que los pacientes preoperatorios electivos poseen una capacidad de defensa de huésped totalmente diferente que la de los pacientes en estado posttrauma o de aquellos con peritonitis. Aparece necesario realizar estudios específicos de inmunidad celular en estos 2 grupos de pacientes; aquello que aporte pertinencia clínica en tales estudios habrá de representar medios para corregir estos defectos. Si tales defectos, mejor denominados anormalidades en las defensas del huésped, son de verdad importantes y contribuyen a mayores tasas de infección y de mortalidad por sepsis en los pacientes afectados, su corrección debe resultar en reducción de estas complicaciones. Esta hipótesis sólo puede ser puesta a prueba cuando tales medios se hallen disponibles. Los aspectos de mayor interés en los próximos años serán el significado de la albúmina sérica en la evolución final del huésped, el papel de los inmunomoduladores, la participación de las citocinas en el proceso general de defensa del huésped, y el uso de regimenes especificos de soporte nutricional dirigidos hacia el sistema inmune.
Résumé La plupart des travaux sur les mécanismes de défense ont été faits sur les populations mixtes. Il est à présent certain que les patients opérés électivement ont des mécanismes de défense préopératoire totalement différents de ceux des traumatisés ou des patients ayant une infection péritonéale. Les études immunologiques sur la médiation cellulaire spécifique méritent d'être refaites chez ces deux populations. Ce qui ressortira de ces études donnera les moyens de corriger les défauts ou plutôt les anomalies des mécanismes de défense qui contribuent à augmenter septicité et mortalité en rapport avec l'état septique. Cette hypothèse ne peut être vérifiée qu'avec ces moyens. Les questions les plus intéressantes dans les années à venir sera peut-être de connaître l'influence de l'albumine sérique sur l'évolution, le rôle des immunomodulaterus, celui des cytokinines dans le procédé global des mécanismes de défense, et celui de l'utilisation de l'alimentation spécifique pour améliorer le système immune.
Supported in part by grants from the Medical Research Council of Canada and the Fonds de recherche de Santé. 相似文献
3.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
4.
J C Marshall C Lee J L Meakins R P Michel N V Christou 《Archives of surgery (Chicago, Ill. : 1960)》1987,122(2):191-196
The effects of global hepatic injury and of Kupffer cell activation on systemic immunity were studied in an in vivo rat model, using the diameters of the delayed-type hypersensitivity (DTH) response to keyhole limpet hemocyanin and of a subcutaneous Staphylococcus aureus abscess as measures of systemic immunoresponsiveness. Hepatic injury with carbon tetrachloride resulted in significant suppression of the DTH score (5.5 +/- 0.7 vs 8.8 +/- 0.8 mm). Kupffer cell activation with intraportal Escherichia coli was likewise suppressive (DTH score, 4.4 +/- 0.5 vs 6.1 +/- 0.4 mm for animals receiving systemic E coli); the magnitude of this suppression correlated with the numbers of organisms extracted by the liver. Conversely, Kupffer cell ablation with carrageenan lessened the immunosuppressive effects of anesthesia and surgery (DTH score, 8.5 +/- 0.9 vs 6.8 +/- 0.6 mm for controls; S aureus abscess, 4.1 +/- 0.4 vs 5.7 +/- 0.4 mm for controls). These results indicate that Kupffer cells can modulate the systemic immune response and suggest that gram-negative portal bacteremia with resultant Kupffer cell activation may contribute to the immunologic derangements characteristic of trauma and critical surgical illness. 相似文献
5.
Advanced primary breast cancer: assessment at mammography of response to induction chemotherapy 总被引:2,自引:0,他引:2
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer. 相似文献
6.
7.
We studied 199 preoperative patients admitted for esophagogastric, gastric, colonic, or rectal resections, 132 patients with severe blunt trauma, 180 surgical intensive care unit patients with major sepsis, and 95 laboratory controls in order to clarify the role of polymorphonuclear neutrophil (PMN) adherence and chemotaxis to outcome. Patients were also stratified by the delayed-type hypersensitivity response to five ubiquitous antigens. PMN adherence and PMN chemotaxis were not different in preoperative reactive or anergic patients and were equal to the control values, whereas both reactive patients and anergic patients showed altered PMN function after trauma or sepsis. There was no difference in PMN adherence or chemotaxis between patients who died and those who lived. Multiple logistic regression analysis showed that patient age, delayed-type hypersensitivity, and admission serum albumin level, not PMN adherence or chemotaxis, were significantly related to septic mortality. We concluded that altered circulating PMN adherence and chemotaxis is seen in all patients after an "activation" event such as trauma or sepsis. This is a nonspecific immune alteration not related to specific immune events such as delayed-type hypersensitivity; it does not correlate with patient outcome and should not be used as a predictive variable. 相似文献
8.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
9.
Dohle GR; Ramos L; Pieters MH; Braat DD; Weber RF 《Human reproduction (Oxford, England)》1998,13(3):620-623
Male genital tract obstructions may result from infections, previous
inguinal and scrotal surgery (vasectomy) and congenital bilateral absence
of the vas deferens (CBAVD). Microsurgery can sometimes be successful in
treating the obstruction. In other cases and in cases of failed surgical
intervention, the patient can be treated by microsurgical or percutaneous
epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction
(TESE) and intracytoplasmic sperm injection (ICSI). We present the results
of 39 ICSI procedures for obstructive azoospermia in 24 couples. The
aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD
in nine and genital infections in four. Sperm retrieval was accomplished
via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was
only applied when PESA failed to produce enough spermatozoa for
simultaneous ICSI. In six patients, the ICSI procedure was performed with
cryopreserved spermatozoa after an initial PESA procedure. Fertilization
occurred in 47% of the metaphase II oocytes; embryo transfer was performed
in 92% of procedures and resulted in a clinical pregnancy in 13/39
procedures. Ongoing pregnancy was achieved in 10/39 procedures. One
pregnancy was terminated early after prenatal investigation showed a
cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine
pregnancies resulted in the live birth of 10 children, without any
congenital abnormalities. Epididymal and testicular retrieved spermatozoa
were successfully used for ICSI to treat obstructive azoospermia, and
resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI
procedures, a success rate of 25.6% per treatment cycle and of 27.7% per
embryo transfer.
相似文献