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91.
Human myeloid alpha 3-fucosyltransferase is involved in the expression of the sialyl-Lewis(x) determinant, a ligand for E- and P-selectin 总被引:1,自引:0,他引:1
Easton EW; Schiphorst WE; van Drunen E; van der Schoot CE; van den Eijnden DH 《Blood》1993,81(11):2978-2986
The sialyl-Lex determinant (NeuAc alpha 2-->3Gal beta 1-->4[Fuc alpha- 1-->3]GlcNAc) has been identified as a major ligand in the selectin- mediated adhesion of neutrophils and monocytes to activated endothelium or platelets. This carbohydrate epitope is formed by the sequential action of alpha 3-sialyltransferase and alpha 3-fucosyltransferase on N- acetyllactosamine (Gal beta 1-->4GlcNAc) disaccharide termini of glycoconjugates. We have addressed the role of the human myeloid alpha 3-fucosyltransferase in the expression of this epitope at the leucocyte surface by determining its activity in human-mouse leukemic cell hybrids (WEGLI), normal human granulocytes and chronic myeloid leukemia (CML) cells using sialylated and desialylated glycoproteins and oligosaccharides as acceptor substrates. In contrast to what has been reported for the myeloid-type enzyme, we found that the alpha 3- fucosyltransferase of the cells studied can use sialylated acceptors be it that the activity is several times lower than with asialo- substrates. Characterization of the product obtained with a sialylated oligosaccharide indicated that the enzyme can catalyze the formation of the sialyl-Le(x) structure. Flow cytometry of the WEGLI cells using a sialyl-Le(x)-specific monoclonal antibody (MoAb) showed that these cells indeed express sialyl-Lex at their surface, provided that they contain human chromosome 11. Earlier the presence of this chromosome had been correlated with the expression of alpha 3-fucosyltransferase activity. In addition to sialyl-Le(x), WEGLI cells containing chromosome 11 showed high-expression levels of related structures recognized by antibodies VIM-2 and VIM-8, suggesting that fucose addition can occur at both distal and proximal GlcNAc residues in poly- N-acetyl-lactosaminoglycan sequences. Based on the human chromosome contents it could be ruled out that the alpha 3-fucosyltransferase of WEGLI cells is a Lewis-type alpha 3/4- or plasma-type alpha 3- fucosyltransferase, the genes of which have been mapped to chromosome 19. It is concluded that the enzyme studied is of the myeloid-type and indeed is involved in the synthesis of sialyl-Le(x) (and also VIM-2 and VIM-8 structures) in leukocytes provided that its expression is at a sufficiently high level. 相似文献
92.
Due to changes in the health care environment that have expanded their role, nurse administrators have less opportunity to respond adequately to employee concerns. The position of staff counseling specialist was designed to assist nurse administrators at the University of Minnesota Hospitals and Clinics meet the increased demands of their staff. The staff counseling specialist provides a means of narrowing the gap between the staff and nurse executives by addressing employee concerns such as inadequate leadership, communication breakdown, dissonant physician-nurse relations, and other matters adversely affecting the work climate. 相似文献
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94.
Acute intracranial epidural haematoma in a basketball player: a case report. 总被引:1,自引:1,他引:0 下载免费PDF全文
A 35-year-old basketball player suffered a serious double head injury during a match. An acute left temporal epidural haematoma, which necessitated surgical drainage, developed. The exceptional circumstances of the trauma are discussed and the literature concerning basketball-related injuries is reviewed. 相似文献
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97.
Infectious complications in the renal transplant recipient 总被引:6,自引:0,他引:6
Grimaldi A Barletta A Rascente M Pisani F Iaria G Maccarone D Maira E D'Angelo M Famulari A 《Transplantation proceedings》2005,37(6):2502-2503
The aim of this study was to estimate the incidence of infectious diseases in a group of patients who underwent kidney transplantation from January 1, 2004 to September 30, 2004, including 121 operations, with 119 from cadaveric and 2 from living donors. The protocol sought herpes viruses (CMV, VZV, and EBV), hepatitis viruses, human immunodeficiency virus, T. gondii, M. tubercolosis, and T. pallidum. Therapy for CMV was used both as prophylaxis in immunoglobulin (Ig)G-negative recipients from IgG-positive donors and preemptive therapy, that is, before the appearance of clinical symptoms, but after viremia reached borderline levels. For VZV infections, the treatment started after the appearance of papulo-vesicular cutaneous eruptions and antibody positivity. The treatment for pneumonia consisted of empirical therapy after radiography; for pyelonephritis, antibiotic therapy was based on the results of kidney echography, blood culture, and urine culture. Infectious complications appeared in 25 patients (20.7%), 3 of the which were polymicrobic: 12 CMV infections, 9 VZV infections, 3 pneumoniae, 4 pyelonephritis, and 1 salmonellosis. The most frequent infection was CMV, which occurred in the first 3 months after transplantation in 9 of 12 cases. This study showed that a knowledge of infection prevalence can help the physician to establish a more specific, efficacious antimicrobial therapy, despite the laboratory response not being available in a short time. 相似文献
98.
Malignancies after kidney transplantation 总被引:1,自引:0,他引:1
Rascente M Pisani F Barletta A D'Angelo M Giammaria A Parzanese I Rizza V Iaria G Famulari A 《Transplantation proceedings》2005,37(6):2529-2531
The most effective treatment of end-stage renal disease is renal transplantation; its superiority to prolong the longevity of patients is well established. Patient and graft survivals have improved with more potent immunosuppression but this advance has been associated with an increased incidence of cancer. The aim of this study was to assess the prevalence of cancer among 265 kidney transplant recipients engrafted between 1968 and October 2004. The overall prevalence of de novo malignancies was 3%. The mean age at diagnosis was 53.3 years (range, 28-63 years) and the duration of the transplant was 11.6 years (range, 0.3-33 years). One patient among 127 (0.8%) who had a history of less than 3 years under immunosuppression, developed a posttransplantation lymphoproliferative disorder (PTLD). Among the 138 patients who had more than 3 years immunosuppression, 7 (5%) developed neoplasms of vulva, colon, native kidneys, prostatic gland, and ovary. One patient was affected by de novo carcinoma in the transplanted kidney. Compared with other published studies, our early cancer prevalence is low, possibly due to a careful history before grafting, good HLA matching, and abstinence from anti-T-cell therapy for treatment of acute rejection episodes. The low level of immunosuppression may account for the low prevalence of neoplasia. The risk of developing a malignancy increases with long-term immunosuppression, comparable with most reports. 相似文献
99.
Epiphrenic diverticuli are rare pulsion "pseudodiverticuli" of the distal oesophagus that are commonly associated with oesophageal motility disorders. Surgical treatment is usually reserved for patients with symptoms. Traditionally, patients are treated with diverticulectomy, myotomy and fundoplication via a left thoracotomy. The aim of this study was to describe the laparoscopic technique and review the international literature on this minimally invasive approach. We report the case of a 66-year-old woman with a 1-year history of retrosternal pain, regurgitation and weight loss caused by an oesophageal epiphrenic diverticulum. The patient underwent barium oesophagography and oesophagogastroduodenoscopy. The oesophageal diverticulum measured 5 cm. We treated the condition with a laparoscopic oesophageal diverticulectomy, Heller myotomy and Dor fundoplication with intraoperative endoscopy. The operative time was 210 minutes. The postoperative course was complicated by a suspected leakage from the staple line, which was not subsequently confirmed. The patient is now totally asymptomatic after 3 months. Laparoscopy offers good access to the distal oesophagus and the inferior mediastinum. Resection of the diverticulum, treatment of the motor disorder and prevention of postoperative reflux can be obtained with this approach. It should be considered as an alternative to the traditional transthoracic approach and may eventually become the standard technique. 相似文献
100.
V. Ruocco M.D. C. Astarita M.D. V. Guerrera M.D. A. Lo Schiavo M.D. C. G. R. Moscariello M.D. R. A. Satriano M.D. M. Pisani M.D. 《International journal of dermatology》1984,23(1):56-60
Kaposi's sarcoma appeared on a chronically lymphedematous leg of a 75-year-old man. Immunologic investigations revealed a lack of cellular immune response confined to the involved lower limb. Regional disorders of immune surveillance are thought to play an important role in the early stages of Kaposi's sarcoma. 相似文献