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1.
von Hippel-Lindau disease affecting 43 members of a single kindred 总被引:22,自引:0,他引:22
We present a 6-generation kindred of over 221 members, 43 of whom were affected with von Hippel-Lindau (vHL) disease. Through a simple screening protocol, we diagnosed vHL retrospectively in 15 cases, and for the first time in 28, 11 of whom were presymptomatic. We found many complications of vHL in previously diagnosed relatives and in new cases. This study has demonstrated the utility and benefit of preventive surveillance in those known to have vHL, and of presymptomatic screening for affected relatives in families with vHL. The features of vHL were reviewed in our 43 cases and 511 cases from the medical literature. The patterns, frequencies, and ages of onset for each lesion were compared. Renal malignancies caused almost as much mortality in vHL as CNS malignancies. This family was exceptional for absence of pheochromocytoma and erythrocythemia, for more renal and pancreatic cysts and malignancies, and for slightly fewer eye or CNS lesions. Bilateral renal adenocarcinomata were found presymptomatically in five young subjects, who had bilateral nephrectomy and hemodialysis. Three survived long-term after renal transplants. Five relatives had pancreatic malignancies, which are definite although uncommon manifestations of vHL. Recommendations are made for family screening, which was economical and effective. Bayesian calculations help to predict risks for genetic counseling. The molecular basis of vHL may soon be found, since it has been linked to DNA markers on the short arm of chromosome 3. 相似文献
2.
James K. Hartsfield Bryan D. Hall Arthur W. Grix Boris G. Kousseff Jose F. Salazar Scott M. W. Haufe 《American journal of medical genetics. Part A》1993,45(5):552-557
We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc. 相似文献
3.
Francis J Podbielski Heron E Rodriguez Andrew M Brown Matthew J Blecha Mario R Salazar Mark M Connolly 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2004,8(3):213-216
Management of an indeterminate pulmonary nodule is a diagnostic challenge that commonly confronts primary care physicians and specialists. Patients often present with this radiographic finding in the course of an unrelated medical evaluation. We examined our institution's experience with percutaneous biopsy of lung nodules to determine the impact of this procedure on overall patient care. Although significant complications are uncommon, the expedience of percutaneous lung biopsy often supplants a surgical opinion prior to initiation of therapy without added diagnostic benefit or cost-savings. Hence, we caution practitioners to use this technique as an adjunct to diagnosis and not a substitute for multidisciplinary care. 相似文献
4.
MD MPHCecilia Albala MD MScMabel Y ez MPh Mat.Sc.Gabriela Salazar MD MPHFernando Vio 《Nutrition Research》1994,14(12):1797-1809
Body composition measured with isotopic dilution was compared with anthropometric measurements. The study was carried out in 47 subjects from both sexes, 65 to 92 years old. Total body water (TBW), anthropometric measurements, and dynamometry were assessed. TBW was significatively higher in men than women and decreased with age. Dynamometry and fatfree mass were well correlated (r=0.73 in males and r=0.58 in females) and significantly different between sexes. A negative correlation was found for dynamometry with age, being significant for women. Linear regression equations to predict TBW from anthropometric measurements in males and females were obtained: Males: TBW(I)=19.349+0.617 weight(kg) — 0.931 mid-arm circumference(cm)+0.122 dynamometry (kg) Females: TBW(l)=−5.531+0.343 weight(kg)-0.213 triceps skinfold (mm)+ 0.148 dynamometry(kg) + 3.424 wrist diameter (cm). This simple model is proposed for use in epidemiological and field studies where other more sophisticated methods can not be applied. 相似文献
5.
6.
Release of soluble transferrin receptor from the surface of human leukemic HL60 cells 总被引:2,自引:0,他引:2
Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4 degrees C. The affinity of Tf for the soluble receptor released by cells (kd = 2.3 x 10(-10) mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (kd = 1.2 x 10(-10) mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease. 相似文献
7.
The envelope protein of the human immunodeficiency virus (gp120) causes neuronal death in developing murine hippocampal cultures or rat retinal ganglion cells. In HIV-infected individuals, gp120 released from HIV-infected macrophages or other cells in the brain has been proposed as the etiology for the pathophysiology of AIDS central nervous system (CNS) disease by diffusing to act at a distance to cause damage and/or death to neighboring neurons. In this study, 28 cerebrospinal fluid (CSF) samples from HIV-infected individuals (79% were WR stage 1 and 2) and neurological disease controls were tested, blind to the investigator, for the presence of in vitro neuronal killing activity. Neurotoxic activity was detected with peak effects at a 1:10(5) dilution in CSF from 9/18 HIV-infected individuals and 1/10 neurological disease controls. Thus half of CSF from early stages of HIV disease are characterized by the presence of neurotoxic activity which is not present in control CSF (Fischers exact test, P < 0.05). The neuronal toxicity by patient CSF could be prevented by peptide T (1 nM). A monoclonal antibody to mouse CD4, RL.172, also attenuated or prevented CSF-induced neuronal killing in all four CSF samples tested. In addition, an antiserum to peptide T previously shown to bind gp120 and neutralize both infectively and direct gp120 neurotoxicity, neutralized the CSF factor. gp120, or a modified small fragment, is suggested to be the responsible toxic molecular entity. These results may be relevant to the pathophysiology of HIV-related CNS disease and the mechanism by which peptide T causes improvements. 相似文献
8.
Sara Lucena Belsy Guerrero Ana M Salazar Amparo Gil Carmen L Arocha-Pi?ango 《Blood coagulation & fibrinolysis》2006,17(6):427-435
Lonomia achelous is a caterpillar distributed in southern Venezuela and in northern Brazil that causes an acute hemorrhagic syndrome in people who have contact with its bristles. The effect of the crude hemolymph and its chromatographic fractions (FDII, Lonomin V and Lonomin V-2) on extracellular matrix proteins was studied. The chromatographic fractions show activities similar to plasmin and urokinase. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, both lonomins appear as a protein band of 25 kDa under reduced conditions. By exclusion chromatography, the molecular weights of Lonomin V and Lonomin V-2 were 26.5 and 24.5 kDa, respectively. Fibronectin, laminin and vitronectin were degraded by all venom components. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, under reduced conditions, shows that lonomins degrade fibronectin in four main fragments of 116, 60, 50 and 30 kDa. Molecular exclusion chromatography in native conditions shows that the molecular masses of these fragments are > or = 300, 62 and 27 kDa. The proteolytic effect of lonomins was abolished by benzamidine/HCl, iodoacetic acid and aprotinin. The extracellular matrix protein degradation together with the fibrino(geno)lytic activity of hemolymph and its fractions could explain, in part, the hemorrhagic syndrome, and the wound dehiscence in persons who have had contact with the L. achelous caterpillar. 相似文献
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10.
M Espada C Pedregal A Alonso C López L Salazar M M Martinez J L Guillén A R Martinez 《Il Farmaco; edizione pratica》1990,45(11):1237-1243
The synthesis of new N3-arylciclohexanespiroimidazolidine-2,4-diones, N3-arylciclohexanespiroimidazolidine-2-tio-4-ones and the 4-hydroxy derivatives is described and their structures discussed on the basis of I.R. and 1H-N.R.M. data. The anthelmintic activity of these compounds was tested. 相似文献