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181.
Identification of the molecular defect in the erythrocyte membrane skeleton of some kindreds with hereditary spherocytosis 总被引:12,自引:0,他引:12
We have localized the molecular alteration in the membrane skeleton of two of four kindreds with hereditary spherocytosis (HS) to an alteration in the spectrin-protein-4.1 interaction due to a defective spectrin molecule. The defective spectrin-protein-4.1 interaction in these kindreds (referred to as type I HS) leads to a weakened spectrin- protein-4.1-actin ternary complex, which in turn may lead to the friable membrane skeleton and suggested membrane instability related to this disorder. Type I HS spectrin binds approximately 63% as much protein-4.1 as normal spectrin (with equal affinity). This defect does not correlate with splenic function or erythrocyte age in the circulation. However, the approximately 37% reduction in binding of protein-4.1 to HS spectrin approaches the theoretical value of 50% expected in this autosomal dominant disorder. All other type I membrane skeletal interactions (spectrin-syndein, spectrin heterodimer- heterodimer, syndein-band-3) were found to be normal. It would appear therefore that the defective HS spectrin-protein-4.1 interaction in type I hereditary spherocytosis may be the primary molecular defect rather than a secondary phenomena. 相似文献
182.
183.
Therapeutic efficacy of recombinant human leukemia inhibitory factor in a primate model of radiation-induced marrow aplasia 总被引:1,自引:0,他引:1
The therapeutic efficacy of recombinant human leukemia inhibitory factor (LIF) was examined in a nonhuman primate model of radiation- induced marrow aplasia. Rhesus monkeys received 450 cGy of total-body, 1:1 mixed neutron:gamma radiation. For 23 days thereafter, each monkey received a daily subcutaneous injection of LIF or human serum albumin (HSA) at a dose of 15 micrograms/kg body weight. Complete blood counts and white blood cell differentials were monitored for 60 days postirradiation. Administration of LIF significantly decreased (P < or = .05) the duration of thrombocytopenia (platelet count < 30,000 or 20,000/microL), ie, 9.3 days or 6.3 days, respectively, versus the HSA- treated control monkeys, 12.2 days or 10.2 days, respectively. Treatment with LIF did not alter the duration of neutropenia (absolute neutrophil count < 1,000/microL) as compared with the HSA-treated control monkeys. Cytokine administration did not exacerbate the radiation-induced anemia observed in the HSA-treated control monkeys. 相似文献
184.
185.
Winton EF; Srinivasiah J; Kim BK; Hillyer CD; Strobert EA; Orkin JL; Swenson RB; McClure HM; Myers LA; Saral R 《Blood》1994,84(1):65-73
Using a recently developed hepsulfam-induced pancytopenia model in rhesus macaques, we have studied the effects of recombinant human interleukin-6 (rhIL-6) and rhIL-3 on marrow regeneration. Control animals were given hepsulfam (1.5 g/m2 by a single 30-minute intravenous [i.v.] injection, n = 4), while study animals received hepsulfam followed by rhIL-6, rhIL-3, or a combination of rhIL-6 and rhIL-3 (n = 3 per study group). Each cytokine was administered by once- daily subcutaneous (SC) injection (15 micrograms/kg/d) for 3 weeks beginning the day after chemotherapy (days 2 through 22). Mean platelet counts in control animals were < 100,000/microL on days 15 through 24, with 50% of the counts < 50,000/microL and two of four animals requiring platelet transfusion. In the rhIL-6- and rhIL-6/rhIL-3- treated groups, the nadir mean platelet counts were 164,000 +/- 58,700/microL and 162,300 +/- 23,800/microL, respectively, and occurred on day 15. Platelet counts in the rhIL-3-treated group were similar to those in controls. Mean absolute neutrophil counts (ANCs) < 1,000/microL occurred on days 10 through 29 in control animals, days 8 through 15 in rhIL-6-treated animals, and days 6 through 8 and 13 in rhIL-6/rhIL-3-treated animals. The frequency of ANCs < 500/microL was significantly less in the rhIL-6- and rhIL-6/rhIL-3-treated groups versus control groups (2.7 +/- 0.6 and 2.0 +/- 1.0 vs 7.0 +/- 1.4 occurrences, respectively; P < .05). rhIL-3-treated animals had ANCs similar to those in controls; one animal died with septicemia on day 21. Monkeys receiving rhIL-6 were significantly more anemic during the cytokine administration period; however, the anemia resolved by day 24. Coadministration of rhIL-3 and rhIL-6 partially corrected the anemia. The data indicate that rhIL-6 prevents significant thrombocytopenia and shortens the neutropenic period in this chemotherapy model. 相似文献
186.
BLANCO F. J.; DE LA MATA J.; LOPEZ-FERNANDEZ J. I.; GOMEZ-REINO J. J. 《Rheumatology (Oxford, England)》1994,33(3):260-266
This study aimed to define prognostic indicators of death inrenal biopsies from Spanish patients with SLE. Renal biopsiesof eighty-five lupus patients with and without clinical nephritis,taken betweeen 1974 and 1987, were reviewed. Samples previouslyprocessed for light (LM), immunofluorescence (IM) and electron(EM) microscopy were analysed blind. Kaplan-Maier curves, log-ranktest, and multivariate Cox's regression statistical methodswere used for comparison of biopsy data in relation to patientsurvival. Univariate analysis showed that vascular hyalinosis,glomerular sclerosis, fibrous crescent and chronicity indexhigher than 3 by LM, and intramembranous dense-deposits by EMare predictors of poor survival. A multivariate approach confirmedthe independent influence of vascular hyalinosis, chronicityindex higher than 3 and intramembranous deposits. A predictivemodel can be constructed with three LM (hyalinosis, tubularatrophy and glomerular sclerosis) and three EM variables (subepithelial,mesangial and intramembranous deposits). Selected renal biopsychanges detected by LM and EM are therefore predictors of deathin patients with lupus. Chronicity markers, more than thoseof activity or severity, are the best prognostic indicators. KEY WORDS: Lupus nephritis, Predictors of mortality in SLE, Survival in lupus nephritis, Electron microscopy, Light microscopy 相似文献
187.
Michel Kahaleh Everson LA Artifon Manuel Perez-Miranda Kapil Gupta Takao Itoi Kenneth F Binmoeller California Pacific Medical Center San Francisco CA United States Marc Giovannini 《World journal of gastroenterology : WJG》2013,19(9):1372-1379
Endoscopic retrograde cholangiopancreatography (ERCP) has become the preferred procedure for biliary or pancreatic drainage in various pancreatico-biliary disorders. With a success rate of more than 90%, ERCP may not achieve biliary or pancreatic drainage in cases with altered anatomy or with tumors obstructing access to the duodenum. In the past those failures were typically managed exclusively by percutaneous approaches by interventional radiologists or surgical intervention. The morbidity associated was significant especially in those patients with advanced malignancy, seeking minimally invasive interventions and improved quality of life. With the advent of biliary drainage via endoscopic ultrasound (EUS) guidance, EUS guided biliary drainage has been used more frequently within the last decade in different countries. As with any novel advanced endoscopic procedure that encompasses various approaches, advanced endoscopists all over the world have innovated and adopted diverse EUS guided biliary and pancreatic drainage techniques. This diversity has resulted in variations and improvements in EUS Guided biliary and pancreatic drainage; and over the years has led to an extensive nomenclature. The diversity of techniques, nomenclature and recent progress in our intrumentation has led to a dedicated meeting on May 7 th , 2011 during Digestive Disease Week 2011. More than 40 advanced endoscopists from United States, Brazil, Mexico, Venezuela, Colombia, Italy, France, Austria, Germany, Spain, Japan, China, South Korea and India attended this pivotal meeting. The meeting covered improved EUS guided biliary access and drainage procedures, terminology, nomenclature, training and credentialing; as well as emerging devices for EUS guided biliary drainage. This paper summarizes the meeting’s agenda and the conclusions generated by the creation of this consortium group. 相似文献
188.
DANILO RICCIARDI M.D. CARLO DE ASMUNDIS M.D. Ph.D. JENS CZAPLA M.D. MARK LA MEIR M.D. PEDRO BRUGADA M.D. Ph.D. FRANCIS WELLENS M.D. Ph.D. 《Pacing and clinical electrophysiology : PACE》2013,36(2):e56-e58
A 71‐year‐old woman with severe nonischemic dilated cardiomyopathy and low ejection fraction with severe mitral regurgitation and tricuspid regurgitation and pulmonary hypertension underwent multiple valve repairs and cardiac resynchronization therapy implantation with epicardial shock leads. (PACE 2013; 36:e56–e58) 相似文献
189.
FERNANDO CABRERA BUENO M.D. Ph.D. JAVIER ALZUETA RODRÍGUEZ M.D. Ph.D. JOSÉ OLAGÜE DE ROS M.D. IGNACIO FERNÁNDEZ‐LOZANO M.D. Ph.D. JUAN JOSÉ GARCÍA GUERRERO M.D. JOAQUÍN FERNÁNDEZ DE LA CONCHA M.D. ANTONIO HERNÁNDEZ MADRID Ph.D. JOSE MARÍA TOLOSANA VIU M.D. JOAQUÍN OSCA ASENSI M.D. ALBERTO BARRERA CORDERO M.D. Ph.D. ELENA LLORENTE HERNANGÓMEZ 《Pacing and clinical electrophysiology : PACE》2013,36(8):963-969
190.
Wang KY; Kimmey MB; Nyberg DA; Mack LA; Haggitt RC; Shuman WP; Franklin DW; Silverstein FE 《Radiology》1987,165(3):827-829
Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses. 相似文献