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781.
Higazi AA; Upson RH; Cohen RL; Manuppello J; Bognacki J; Henkin J; McCrae KR; Kounnas MZ; Strickland DK; Preissner KT; Lawler J; Cines DB 《Blood》1996,88(2):542-551
Binding of urokinase-type plasminogen activator (uPA) to its glycosylphosphatidylinositol-anchored receptor (uPAR) initiates signal transduction, adhesion, and migration in certain cell types. To determine whether some of these activities may be mediated by associations between the uPA/uPAR complex and other cell surface proteins, we studied the binding of complexes composed of recombinant, soluble uPA receptor (suPAR) and single chain uPA (scuPA) to a cell line (LM-TK- fibroblasts) that does not express glycosylphosphatidylinositol (GPI)-anchored proteins to eliminate potential competition by endogenous uPA receptors. scuPA induced the binding of suPAR to LM-TK- cells. Binding of labeled suPAR/scuPA was inhibited by unlabeled complex, but not by scuPA or suPAR added separately, indicating cellular binding sites had been formed that are not present in either component. Binding of the complex was inhibited by low molecular weight uPA (LMW-uPA) indicating exposure of an epitope found normally in the isolated B chain of two chain uPA (tcuPA), but hidden in soluble scuPA. Binding of LMW-uPA was independent of its catalytic site and was associated with retention of its enzymatic activity. Additional cell binding epitopes were generated within suPAR itself by the aminoterminal fragment of scuPA, which itself does not bind to LM-TK- cells. When scuPA bound to suPAR, a binding site for alpha 2-macroglobulin receptor/LDL receptor-related protein (alpha 2 MR/LRP) was lost, while binding sites for cell-associated vitronectin and thrombospondin were induced. In accord with this, the internalization and degradation of cell-associated tcuPA and tcuPA-PAI- 1 complexes proceeded less efficiently in the presence of suPAR. Further, little degradation of suPAR was detected, suggesting that cell- bound complex dissociated during the initial stages of endocytosis. Thus, the interaction of scuPA with its receptor causes multiple functional changes within the complex including the dis-appearance of an epitope in scuPA involved in its clearance from the cell surface and the generation of novel epitopes that promote its binding to proteins involved in cell adhesion and signal transduction. 相似文献
782.
AA Al-shaham 《CANADIAN JOURNAL OF PLASTIC SURGERY》2012,20(2):e28-e31
BACKGROUND:
Reconstruction of acquired auricular defects is a challenging procedure. Since its emergence, the helical advancement technique has proved to be an excellent method of repairing many auricle defects. This technique may occasionally result in an alteration in the dimensions of the neoauricle, with subsequent deformity. However, the advantages of this technique are well known, while the pitfalls are scarce.OBJECTIVE:
To critically review the selection criteria of patients with acquired auricular defects to determine which are eligible for helical advancement technique without subsequent deformity.METHODS:
From March 2004 to January 2006, 18 patients with three types of upper one-third auricle defects underwent the helical advancement procedure. All patients were male, with mean age of 33.5 years. The defects ranged from 1.2 cm to 4.3 cm in length. Two helical flaps (one on either side of the injury) were advanced along the helical margin to ensure closure. The vertical and horizontal auricular axes were measured before and after surgery, and the actual reduction in millimetres was calculated. Patients were followed up for three months postoperatively. Assessment of the surgical outcome was performed by surgeon (with patient feedback) in the final patient visit.RESULTS:
The principle pitfall in the form of small neoauricle with or without cupping was reported in five patients (27.77%). The defects in these cases were >2.8 cm and the mean resultant reduction in vertical axes was >5 mm. Statistical analysis resulted in χ2=4.24 and P=0.04CONCLUSION:
The three varieties of upper one-third auricle defects can best be corrected by the helical advancement technique when the defect is <2.8 cm. Furthermore, perioperative reduction in the vertical axis of the neoauricle >5 mm was an important predictive factor in the development of subsequent deformity. 相似文献783.
H Turki S Zoghi A A Mehrizi S Zakeri A Raeisi H Khazan AA Haghdoost 《Iranian Journal of Parasitology》2012,7(1):36-44
Background
A successful malaria elimination program calls for enough attention to parasite carriers, especially asymptomatic malaria, as well as the diagnosis and treatment of clinical cases. Asymptomatic malaria is an infection that patients do not show any symptom; thus, these patients play critical role in the concept of an elimination program. The current investigation was conducted to evaluate the presence of these cases in Bashagard District, formerly a high malaria transmission area in Hormozgan Province, Iran.Methods
Blood samples (n = 500) were collected from symptomless individuals residing in Bashagard to evaluate Plasmodium infection by using microscopic, serological and nested-PCR techniques.Results
Regarding the microscopic and nested-PCR analysis, no asymptomatic infection was detected among studied individuals. Totally, 1% of the studied population (5 of 500) had anti PvMSP-119-specific IgG antibody; however, only 0.2% (1 of 500) of the individuals was seropositive to recombinant PfMSP-119, using ELISA.Conclusion
This study showed no asymptomatic malaria infection in the studied population; hence malaria elimination is feasible and can be successfully carried out in this region. 相似文献784.
Background
Fasciolosis is an important health and veterinary problem in Iran. The epidemiological pattern of disease has been changed markedly in recent years and there are regions that have potent capacity to be new focus of the disease. One of these areas is Yasuj district in southwest of Iran where animal fasciolosis has been quite common. The current study was conducted to determine the seroprevalence of human fasciolosis in this area and to reveal the epidemiological factors associated with the spreading of the disease in this region.Methods
One thousand blood samples were randomly collected from five villages in Yasuj district. ELISA, using Fasciola somatic antigen (SA), was carried out to detect anti Fasciola antibodies in the collected sera.Results
Anti-Fasciola antibodies were detected in serum of 18(1.86%) individuals by ELISA. Out of 18 seropositive people, 9 (0.9) were female and 9 (0.9%) were male. Most of people (99.8%) had a history of consuming wild freshwater plants mainly Nasturtium microphyllum (local name Bakaloo) and/or Mentha logifolia (local name Pooneh). No significant correlation was found between seropositivity to fasciolosis and sex, age, history of consumption of green leafy aquatic plants whereas correlation between seropositivity and abdominal pain was significant (P< 0.05).Conclusion
Results of this study showed that the seroprevalence rate of human fasciolosis in Yasuj district is relatively high and this area can be considered as a new emerging focus of the disease in Iran. 相似文献785.
Enhanced nitric oxide release during cortical spreading depression following infusion of glyceryl trinitrate in the anaesthetized cat 总被引:2,自引:0,他引:2
SJ Read MI Smith AJ Hunter AA Parsons 《Cephalalgia : an international journal of headache》1997,17(3):159-165
Intravenous infusion of glyceryl trinitrate (GTN) into migraineurs induces an immediate headache followed by migraine. We studied the effect of GTN 10.25 g kg1 min 1 ) on local cerebrovascular laser Doppler flux (rCBFLDF ), artery diameter and NO concentration (selective NO microelectrode) in the pial middle cerebral artery perfusion territory of the anaesthetized cat, at rest and during cortical spreading depression (SD). GTN infusion induced a significant increase in pial artery diameter, rCBFLDF , and NO concentration. Following termination of infusion, NO concentrations remained significantly elevated above controls for 60 min, other parameters returned to baseliae within 10 min ( p 0.05, ANOVA, post hoc Dunnett's multiple comparison procedure). Two hours after termination of infusion KCl-evoked SD was initiated. GTN-treated animals exhibited significantly ( p 0.05, Kruskal-Wallis) elevated SD-induced NO release compared to controls. All other parameters remained unaffected. Our results demonstrate that GTN induces a prolonged increase in local NO concentrations and enhances SD-induced NO release. 相似文献
786.
BACKGROUND: After differentiation of the entities of clinically detectable delayed hemolytic (DHTR) and delayed serologic transfusion reactions (DSTR), previous investigators calculated a DHTR:DSTR incidence ratio of 18:72 from a retrospective review of patients with serologic evidence of DHTR or DSTR. There are no published data on factors that may influence the occurrence of DHTR versus DSTR in a given patient. STUDY DESIGN AND METHODS: Retrospective review was conducted of 292 patients at the Mayo Clinic who, between 1980 and 1992, received a clinical diagnosis of DHTR or DSTR concurrently with a serologic diagnosis. Red cell alloantibody specificity, the activity of the patient's reticuloendothelial system, and concurrent immunosuppression were evaluated as potential predictors of the occurrence of DHTR versus DSTR in different patients. RESULTS: The incidence of DHTR or DSTR was 1 in 1899 allogeneic red cell units transfused, with a DHTR:DSTR ratio of 36:64. Alloantibody specificity was the only variable that affected the occurrence of DHTR versus DSTR at the clinical level, with the anti-Jka and anti-Fya specificities, as well as multiple coexisting specificities, significantly associated with detectable hemolysis (p < 0.05). CONCLUSION: Clinically detectable DHTRs are found to occur more commonly than previously believed when the clinical and serologic diagnoses are made concurrently and appropriate work-ups for hemolysis are ordered. The association of certain alloantibody specificities with detectable DHTRs may have implications for clinical transfusion practice. 相似文献
787.
AA Le Roux 《Physiotherapy》1995,81(12):716-717
788.
Furosemide inhibits regenerative cortical spreading depression in anaesthetized cats 总被引:2,自引:0,他引:2
SJ Read MI Smith CD Benham AJ Hunter AA Parsons 《Cephalalgia : an international journal of headache》1997,17(8):826-832
Ionic perturbations occur during cortical spreading depression (SD), a phenomenon implicated in migraine pathophysiology. We studied the effect of 0.2,2 and 20 mg kg−1 iv ( n =4) furosemide on cortical direct current (d.c.) potential, cerebrovascular laser Doppler flux (rCBFLDF ), artery diameter and NO concentration in the parietal cortex of the anaesthetized cat during repetitive SD. In vehicle treated animals ( n =4), SD activity was sustained for 50 1.8 min. However, duration of SD activity was significantly reduced when compared to vehicle to 39 6.6 ( n =4), 3.1 8.3 ( n =4) and 27.3 11.3 min ( n =4), at 0.2, 2 and 20 mg kg−1 iv furosemide respectively. It is hypothesized that the mechanism of inhibition of SD d.c. activity by furosemide may be through alterations in cortica ion buffering capacity or inhibition of cell swelling in neurones or glia. These mechanisms may represent potential novel drug targets in future migraine therapy. 相似文献
789.
Recombinant immunoblot assay reaction patterns and hepatitis C virus RNA in blood donors and non-A, non-B hepatitis patients 总被引:5,自引:0,他引:5
D Bresters ; HL Zaaijer ; HT Cuypers ; HW Reesink ; IN Winkel ; PJ van Exel-Oehlers; AA van Drimmelen; PL Jansen ; CL van der Poel; PN Lelie 《Transfusion》1993,33(8):634-638
To establish the value of the second-generation recombinant immunoblot assay (RIBA-2) and cDNA polymerase chain reaction (cDNA PCR) for confirmation of hepatitis C virus (HCV) infection, anti-HCV reaction patterns and the presence of HCV RNA were examined in 610 blood donors and 255 non-A, non-B hepatitis patients who were positive or indeterminate in RIBA-2. Of RIBA-2-positive donors (n = 191) and patients (n = 224), 75.4 and 89.7 percent, respectively, were HCV RNA positive. The most frequently observed anti-HCV recognition patterns in HCV RNA-positive donors and patients were c22, c33c, and c100 and/or 5- 1-1 (67.3%, 57.7%) and c22, c33c (24.8%, 29.3%). Among subjects with a RIBA-2-indeterminate result, HCV RNA was detected more often in patients (n = 31) than in donors (n = 419): 67.7 and 2.1 percent, respectively. In viremic persons with single-band reactivity in RIBA-2, this reactivity was always directed against either c22 or c33c. HCV RNA was detected by cDNA PCR in none of 162 persons with only anti-c100 and/or anti-5-1-1 reactivity. Therefore, RIBA-2 reactivity against c100 in combination with 5-1-1 should not be considered positive but indeterminate. In RIBA-2-indeterminate persons, HCV RNA detection is necessary for reliable confirmation of HCV infection. 相似文献
790.