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1.
Primary malignant melanoma of the bladder 总被引:1,自引:0,他引:1
MAURO PACELLA FABRIZIO GALLO CHRISTIAN GASTALDI CARLO AMBRUOSI GIORGIO CARMIGNANI 《International journal of urology》2006,13(5):635-637
Primary malignant melanomma of bladder is extremely rare: 18 cases are reported to date. An 82 year-old man underwent trans-urethral resection of bladder for a bleeding tumor of the posterior wall. Histological diagnosis was melanoma of the bladder. There was no history of previous or regressed cutaneous malignant melanoma. Margins of the bladder lesion contained atypical melanocytes similar to those commonly seen in the periphery of primary mucous membrane lesions. Clinical studies and radiological examinations were negative for other primary site of melanoma. The patient had a bladder recurrence that was consistent with primary tumor and died of widespread disease 9 months after diagnosis. 相似文献
2.
NICOLAY GENOV BRUNO FILIPPI PAVLINA DOLASHKA KEITH S. WILSON CHRISTIAN BETZEL 《Chemical biology & drug design》1995,45(4):391-400
The stability towards thermal and chemical (guanidine hydrochloride, GnHCl) denaturation of six inhibited subtilases (mesentericopeptidase, subtilisins BPN′, Carlsberg and DY, proteinase K and thermitase) has been investigated by kinetic and equilibrium studies. The unfolding processes were monitored by circular dichroic and fluorescence spectroscopy. Experiments in the absence and presence of extraneous calcium in the concentration range 2×10?3-10?1 M were performed. The presence of calcium in the weak calcium binding site changes the denaturation drastically. The heat- (or GnHCl-) induced unfolding curves obtained using CD spectroscopy show two independent transitions which seem not to have been resolved before. The presence of Ca2+ in the second (third in the case of thermitase) binding site increases the Tm, values by 11-21 °C and the δGD(H2O) values obtained from denaturation experiments in GnHCl by 6.7-7.2 kcal/mol when an extraneous Ca2+ concentration of 2 × 10?2 M was used. One interpretation is that the initial step of denaturation in the presence of added calcium is the formation of a partially unfolded intermediate form, retaining a highly ordered structure with 60-85% of the a-helix structure of the native enzyme. This intermediate then unfolds at a temperature considerably higher than that of the same proteinases in the absence of added Ca2+. The free energy of stabilization of the intermediates is increased by 1.8-2.8 times in comparison with that for the unfolding reactions of the subtilases with empty Ca2/Ca3 binding sites. A second interpretation is that the two steps in the unfolding curves correspond to enzyme without and with calcium in the weak binding site. Fluorescence experiments confirm the mechanism involving the formation of intermediate states. The results are discussed in relation to the X-ray models of the six subtilases. 相似文献
3.
NICOLAS SADOUL M.D. BERNARD DODINOT M.D. DANIEL BEURRIER M.D. CHRISTIAN DE. CHILLOU M.D. ETIENNE ALIOT M.D. 《Journal of interventional cardiology》1996,9(4):347-353
Dual chamber pacing is a new indication for the treatment of drug resistant hypertrophic obstructive cardiontyopathy (HOCM) in patients with normal atrioventricular (AV) conduction. In sinus rhythm, the efficacy of the treatment is mainly related to the ability to bypass the normal AV conduction system in order to obtain a complete and permanent right ventricular (RV) capture. This is achieved by programming short AV delays. On the other hand, patients with HOCM frequently have co-existing left ventricular diastolic dysfunction, and the atrial contribution to left ventricular filling is critical. The lack of improvement, rarely encountered, is probably due to incomplete RV capture andlor to the deleterious effect of short AV delay. Instrumental AV node prolongation may he indicated in this situation. This procedure should be undertaken when previous drug-induced AV prolongation has failed. In theory, AV node modulation (i.e., creating a I ± AV block) seems ideal. However, this technique remains difficult, with disappointing chronic results. Most authors hence perform "conventional" AV node ablation. Particular attention is taken in order to perform a proximal node ablation, resulting in a complete AV block with narrow QRS escape rhythm. The reported incidence of AV node prolongation ranges from 7.5%-37.5%. The efficacy of the procedure on symptoms is explained by improved left ventricular filling and/or a further reduction in the systolic gradient evoked by complete RV capture. Another indication for AV node ablation in HOCM is the occurrence of atrial fibrillation, in order to restore adequate and permanent RV capture . 相似文献
4.
RAFAEL BEYAR M.D. D.Sc. ARIEL ROGUIN M.D. JAAP HAMBURGER M.D. RE SAAIMAN M.D. ANTONIO L. BARTORELLI M.D. CARLO DiMARIO M.D. ANTONIO COLOMBO M.D. CHRISTIAN W. HAMM M.D. CHRISTOPHER J. WHITE M.D. J. MARCO M.D. PATRICK W. SERRUYS M.D. Ph.D. 《Journal of interventional cardiology》1997,10(4):277-286
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics. 相似文献
5.
Developmental Toxicology Studies of Vancomycin Hydrochloride Administered Intravenously to Rats and Rabbits 总被引:1,自引:0,他引:1
Pregnant CD rats were given vancomycin intravenously in dosesof 0, 40, 120, or 200 mg/kg on Gestation Days (GD) 615;pregnant New Zealand white rabbits were given 0, 40, 80, or120 mg/kg intravenously on GD 618. Cesarean sectionswere performed on rats and rabbits on GD 20 and 28, respectively.In rats, maternal toxicity was indicated in the 120- and 200-mg/kgtreatment groups by cortical tubular nephrosis. Maternal bodyweight gain and food consumption and fetal viability, weight,and morphology were not adversely affected by vancomycin. Maternaland developmental no observed adverse effect levels (NOAELs)in the rat were 40 and 200 mg/kg, respectively. In rabbits,maternal toxicity was indicated by cortical tubular nephrosisin the 80- and 120-mg/kg treatment groups; a single death anddepression of body weight gain and food consumption occurredin the 120-mg/kg treatment group. Developmental toxicity wasindicated by depression of fetal weight in the 120-mg/kg treatmentgroup; fetal viability and morphology were not adversely affectedby vancomycin. Maternal and developmental NOAELs in the rabbitwere 40 and 80 mg/kg, respectively. Based on these data, vancomycindid not exhibit selective toxicity toward the developing rator rabbit conceptus. 相似文献
6.
CARMINE MINALE M.D. SIGRID NIKOL M.D. GUNTER HOLLWEG M.D. CHRISTIAN MITTERMAYER M.D. † BRUNO J. MESSMER M.D. 《Journal of cardiac surgery》1988,3(3):193-201
Complete closure of the pericardium after cardiac operations has the advantage of avoiding injury of the heart and great vessels during reoperation. Between 1985 and 1987, the pericardium was closed with Gore-Tex Surgical Membrane (SM) in a selected series of 110 patients 1 month to 76 years of age. Fifty-three patients had congenital heart lesions and 57 patients had acquired heart disease. Overall hospital mortality was 3/110 cases. In no instance was there a relationship between occurrence of death and pericardial closure with SM. There was one episode of cardiac tamponade on the seventh postoperative day. One patient developed fever and leukocytosis due to a mediastinal hematoma. During a mean follow-up of 15 months, four patients had to be reoperated upon three, four, eight weeks, and eight months after primary operation. The anterior wall of the heart had no adhesion with the SM and the other parts of pericardium could be dissected easily. Scanning electron microscopic examination of the explanted SM patches showed neither cellular ingrowth nor immunocompetent cellular elements. The Gore-Tex Surgical Membrane has the advantages of easy availability and lack of reaction between its surface and the epicardium and pericardium. We believe its routine use should be encouraged in patients with high probability of reoperation after repair of complex cardiac anomalies, implantation of bioprostheses, coronary revascularization for one- or two-vessel disease, and repair of degenerative disease of the ascending aorta. 相似文献
7.
Evening administration of melatonin and bright light: Interactions on the EEG during sleep and wakefulness 总被引:1,自引:0,他引:1
CHRISTIAN CAJOCHEN KURT KRÄUCHI KONSTANTIN V. DANILENKO & ANNA WIRZ-JUSTICE 《Journal of sleep research》1998,7(3):145-157
Both the pineal hormone melatonin and light exposure are considered to play a major role in the circadian regulation of sleep. In a placebo- controlled balanced cross-over design, we investigated the acute effects of exogenous melatonin (5 mg p.o. at 20.40 hours) with or without a 3-h bright light exposure (5000 lux from 21.00 hours–24.00 hours) on subjective sleepiness, internal sleep structure and EEG power density during sleep and wakefulness in healthy young men. The acute effects of melatonin, bright light and their interaction were measured on the first day (treatment day), possible circadian phase shifts were assessed on the post-treatment day. On the treatment day, the evening rise in subjective sleepiness was accelerated after melatonin and protracted during bright light exposure. These effects were also reflected in specific changes of EEG power density in the theta/alpha range during wakefulness. Melatonin shortened and bright light increased sleep latency. REMS latency was reduced after melatonin administration but bright light had no effect. Slow-wave sleep and slow-wave activity during the first non-rapid eye movement (NREMS) episode were suppressed after melatonin administration and rebounded in the second NREMS episode, independent of whether light was co-administered or not. Self rated sleep quality was better after melatonin administration whereas the awakening process was rated as more difficult after bright light. On the post-treatment day after evening bright light, the rise in sleepiness and the onset of sleep were delayed, independent of whether melatonin was co-administered or not. Thus, although acute bright light and melatonin administration affected subjective sleepiness, internal sleep structure and EEG power density during sleep and wakefulness in a additive manner, the phase shifting effect of a single evening bright light exposure could not be blocked by exogenous melatonin 相似文献
8.
CHRISTIAN STR
M JAN M. LUNDBERG HKAN AHLMAN ANNICA DAHLSTR
M JAN FAHRENKRUG TOMAS H
KFELT 《Acta physiologica (Oxford, England)》1981,111(2):213-215
Chronic ACTH treatment (3 IU/kg daily for 8 days) caused an increase in wet weight of the interscapular brown adipose tissue (ISBAT) in the rat without affecting the enzyme activities of the cardiac or skeletal muscles or of ISBAT. On the other hand, chronic β-blockade (alprenolol 10 mg/kg daily for 8 days) induced elevated activities in the oxidative enzymes of the ISBAT but not of the muscle tissues measured. Combined ACTH and alprenolol treatment also increased significantly the citrate synthase and malate dehydrogenase activities and protein concentration, but decreased the weight of ISBAT to normal. The results suggest that, although a direct antagonism between the β-blockers and ACTH has not been demonstrated, β-blockers can abolish the ACTH-induced weight gain of the ISBAT. 相似文献
9.
HOBERMAN A. M.; CHRISTIAN M. S.; LOVRE S.; ROTH R.; KOSCHIER F. 《Toxicological sciences》1995,28(1):34-40
Pregnant CD rats were exposed dermally to 0.05, 1, 10, 50, and250 mg/kg/day of Clarified Slurry Oil (CSO) on Days 019of gestation to determine its potential developmental toxicity.Untreated and vehicle controls were included in the study. Day20 of gestation Caesarean-derived fetuses were examined forgross, external, and visceral or skeletal alterations. Dosagesof 1 mg/kg/day and higher significantly decreased maternal bodyweight, body weight gain, feed consumption, gravid uterine weight,and live litter size and significantly increased resorptionrate. These dosages also significantly reduced fetal weightsand retarded development of the brain, kidney, thoracic andcaudal vertebrae, metacarpals, and hindpaw phalanges in dosagegroups with live fetuses (high dosage group dams resorbed allconceptuses). The 50- and 250-mg/kg/day dosage group dams hadonly placentas and/or dark red viscous fluid in the uterus orvagina and significant body weight loss (associated with resorption).The highest dosage also caused emaciation, slight dehydration,and swollen dark anogenital areas. These results indicate thatCSO produces adverse developmental effects at maternally toxicdosages. The maternal and developmental NOAELs (no observedadverse effect levels) were 0.05 mg/kg/day. In a second study,groups of 10 mated female rats were exposed to "pulse" exposuresand dosages of 1, 50, or 250 mg/kg/day of CSO applied dermallyfor 2- or 3-day intervals that spanned the gestation period.All dosages reduced maternal feed consumption and body weightgain during the treatment period. Dosages of 50 and 250 mg/kg/dayalso produced early resorptions when administered on Days 6through 8 and 9 through 11 of gestation. However, no increasein fetal alterations occurred, indicating that the effects onembryofetal development were due to early death and notto the death of malformed conceptuses. 相似文献
10.
1. Severe hemolytic reactions were observed in 3 group A (subgroup A1) recipients transfused with group O whole blood or plasma. In one case, 10 ml. of acommerical preparation of soluble A and B factors had been added to 500 ml. ofwhole blood prior to the transfusion and it is believed that the reaction mighthave been even more serious had not this material been added.2. The anti-A antibodies in the serum of the dangerous universal donors causingthe hemolytic reactions fixed complement, acted as hemolysins, were difficult toneutralize with soluble A and B factors, were capable of giving positive Coombstests and their ability to agglutinate A cells was enhanced by the presence of normal human serum. These characteristics were similar to those observed in serumfrom donors known to be actively immunized against the A factor, but the stimulusfor development of "immune" anti-A antibodies in the dangerous group O donorswas not apparent.3. Small amounts of immune A antibody were consistently demonstrated in 12of 100 random group O sera which, after neutralization, produced indirect Coombstests with A1 cells and agglutinated A1 cells suspended in compatible normal humanserum.4. Screening procedures for elimination of dangerous group O donors are discussed. Note: ACKNOWLEDGMENTSIt is a pleasure to thank Mrs. Jane Peters, Mrs. Nieves Dole and Miss Jean Dorothy for technicalassistance and Dr. R. Wendell Davis for collaboration in the study of Case 1. 相似文献