227. Der gestielte Peronaeus-Insellappen als Alternative zum freien Gewebetransfer am distalen Unterschenkel und Fuß

Zusammenfassung Der distal gestielte Peronaeus-Insellappen, erstmals 1984 von Yoshimura publiziert, ist ein fasciocutaner Lappen, der über einen Hautast der A. peronea ernährt wird. Die A. peronea weist distal, ca 5 cm oberhalb des Sprunggelenkes, einen Ramus perforans zur A. tibialis anterior auf und über einen Ramus communicans besteht eine Verbindung zur A. tibialis posterior. Unterbindet man die A. peronea proximal der Abgangsstele der Hautarterie, so kommt es über die distalen Anastomosen zur retrograden Durchblutung. Der distal gestielte Peronaeuslappen besitzt einen großen Schwenkbereich bis hin zum Fußrücken. Die Durchgängigkeit der drei Unterschenkelarterien ist die Voraussetzung für die Durchführbarkeit. Die Indikation ergibt sich bei oberflächlichen Knochen- und Hautdefekten im distalen Unterschenkeldrittel, der Malleolengabel, der Ferse und des Fußrückens.     

Allografts of CNS tissue possess a blood-brain barrier. II. Angiogenesis in solid tissue and cell suspension grafts

Angiogenesis and patency of blood vessels were analyzed qualitatively in solid CNS and peripheral tissue syngeneic, allogeneic, and xenogeneic grafts and in individual cell suspension grafts of astrocytes, fibroblasts, PC12, and three additional tumor cell lines placed intracerebrally in adult host mice. Postgrafting survival times were 1 day through 4 weeks. The patency of graft vessels was determined in sections from immersion-fixed tissues incubated to reveal the endogenous peroxidase activity of host red cells trapped within the lumen of blood vessels. Additionally, horseradish peroxidase (HRP) was administered intravenously to live hosts; HRP labels host brain and graft vessels on the luminal surface and reveals the presence or absence of a blood-brain barrier (BBB) within the grafts. The origins of blood vessels supplying solid tissue xenografts were identified immunohistochemically with primary antibodies against host (athymic AKR mice) and donor (fetal Lewis rats) major histocompatibility complex (MHC) class I. Blood vessels supplying solid CNS grafts at 1-7 days post-transplantation were identified ultrastructurally and possessed interendothelial tight junctional complexes; however, they were not perfused with either host blood or blood-borne HRP prior to 8 days. Graft vessels at 10 days were outlined consistently by peroxidase-positive red cells in immersion-fixed material and labeled with blood-borne HRP. These vessels provided a BBB to the circulating HRP and exhibited interendothelial tight junctions. Evidence of angiogenesis within solid anterior pituitary grafts and the variety of cell suspension grafts was obtained prior to 3 days post-transplantation in immersion-fixed preparations; the vessels, with the notable exception of those supplying astrocyte cell suspensions, failed to present a BBB to blood-borne peroxidase. Endothelia in the solid pituitary allografts and the PC12 cell grafts were highly fenestrated and exhibited open interendothelial junctions; those in the tumor and fibroblast cell grafts, for the most part, appeared nonfenestrated, and many possessed open interendothelial junctional complexes. Immunostaining for host and donor MHC class I revealed that donor blood vessels predominate over host vessels in CNS xenografts and supply pituitary xenografts exclusively; in both preparations, donor vessels were not identified within the host CNS. Because cell suspension grafts were derived from endothelia-free preparations grown in culture, blood vessels supplying these grafts were necessarily of host CNS origin and manifested a morphological transformation from a BBB to a non-BBB endothelium. The data suggest that angiogenesis in solid CNS grafts placed into the adult host CNS, compared to similarly placed solid peripheral tissue/cell suspension grafts, is not rapid.(ABSTRACT TRUNCATED AT 400 WORDS)     

Treatment of a recurrent inguinal lymphocele in a penis cancer patient by lymphography and selective ligation of lymphatic vessels

We report a case of recurrent inguinal lymphocele formation after inguinal lymphadenectomy treated by lymphographic mapping and selective ligation of the lymphatic vessels. Lymphographic mapping was performed by puncturing a lymphatic vessel at the dorsum of the foot. After isolating the vessels that drained into the lymphocele, they were clipped and divided through a small skin incision. The described technique showed an instant and complete suspension of the lymph secretion with subsequent complete healing. Lymphatic mapping and selective ligation of afferent lymphatic vessels proved to be an effective treatment of a recurrent inguinal lymphocele.     

Effects of the AMPA receptor antagonist NBQX on the development and expression of behavioral sensitization to cocaine and amphetamine

 We examined the effect of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX), an antagonist of the α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) subtype of glutamate receptor, on the development and expression of behavioral sensitization to amphetamine and cocaine in rats. A single injection of NBQX (12.5 mg/kg) administered 30 min prior to cocaine during the induction phase (days 1–5) prevented the development of cocaine sensitization, assessed by responsiveness to cocaine challenge on day 8. This NBQX regimen did not affect development of amphetamine sensitization. Two pretreatment injections of NBQX, one 20 min before and one 70 min after amphetamine on each day of the induction phase (days 1–6), did not affect sensitization of stereotypy but prevented sensitization of post-stereotypy ambulatory hyperactivity (both assessed by responsiveness to amphetamine challenge on day 8). The effect of NBQX on ambulatory sensitization was dose-dependent (attenuation with 12.5 mg/kg, complete prevention with 25 mg/kg). In contrast to its effects on development, NBQX (25 mg/kg) did not prevent expression of sensitization to cocaine or amphetamine. NBQX itself exerted no significant effects on locomotor activity in either drug-naive rats or rats that had received either NBQX or amphetamine repeatedly. These findings support a requirement for AMPA receptor stimulation in the development of locomotor sensitization to cocaine and amphetamine, but suggest a different mechanism for sensitization of amphetamine stereotypy. Received: 14 January 1997 / Final version: 24 June 1997     

Origins of heterogeneous ovarian carcinomas. A molecular cytogenetic analysis of histologically benign, low malignant potential, and fully malignant components.

It is unclear whether ovarian carcinomas develop from malignant transformation of benign precursors or whether they arise de novo. Thus, histologically benign or low malignant potential components found in heterogeneous ovarian carcinomas may be remnants of pre-existing lesions that progressed to malignancy or, alternatively, elements that arose independently (de novo). In a third possible interpretation, they represent areas of malignant epithelium that matured. We evaluated clonal relationships of histological components in 10 heterogeneous ovarian carcinomas using fluorescence in situ hybridization and confocal microscopy. Detailed analysis of aneuploidy for chromosomes 8, 12, and 17 on intact paraffin sections revealed that two tumors were aneuploid in all components, two lacked abnormalities in benign-appearing components, and one lacked aneuploidy in both histologically benign and low malignant potential components. Histological appearance was significantly related to aneuploidy (P < 0.05). The distribution of aneuploidy among tumor components strongly supports the tumor progression theory and demonstrates that the de novo hypothesis is highly unlikely (P < 0.001). Results also indicate that benign-appearing components in heterogeneous ovarian carcinomas do not represent maturation of malignant tissue and suggest that some benign tumors that become cancerous may have genetic aberrations that predispose them to malignant transformation.     

Graduating medical students' ratings of stresses, pleasures, and coping strategies

The authors' objective in the study reported here was to gather data on the stress and coping of medical students in order to design a health promotion and wellness program. A retrospective questionnaire was completed by 71 of 157 graduating seniors. Examinations, classwork, and financial responsibilities were considered the three most stressful aspects of medical education. The most uplifting items (that is, pleasant, happy, or satisfying experiences) were recreation and social interaction, although good examination performance was rated second highest. Planful problem-solving (that is, deliberate problem-focused efforts to alter a situation) was the most frequently used form of coping, although four of the eight forms of coping assessed were used at least moderately often and all eight were used to some extent.     

Phase II evaluation of merbarone in renal cell carcinoma

Summary The Southwest Oncology Group (SWOG) studied the response rate and toxicity of merbarone (1,000 mg/m² IV continuous infusion days 1–5, q 21 days) in patients with advanced metastatic renal cell carcinoma. Among 36 eligible patients, there was one partial response for a response rate of 3% (95% C.I. 0.1–15%). There were no mixed responses. There were no treatment related deaths or adverse drug reactions. Significant anemia, diarrhea, and hypercalcemia were observed. Mild to moderate degrees of malaise/fatigue/lethargy, dizziness/vertigo, hyperglycemia, creatinine increase, nausea, vomiting, weight loss, pedal edema, dyspnea, and granulocytopenia were noted. Merbarone does not have significant activity as a single agent in advanced renal cell carcinoma.     

Ischemic monomelic neuropathy: An under-recognized complication of hemodialysis access

During the past 3 years six episodes of ischemic monomelic neuropathy (IMN) have been identified in five patients as a complication of upper extremity dialysis grafts. All patients had long-standing insulin-dependent diabetes, peripheral neuropathy, and brachial artery graft origins, whereas 60% had peripheral vascular disease. Five episodes occurred immediately after graft placement, whereas one was due to a graft-related thromboembolus. Diagnostic delay was common with initial findings attributed to anesthesia, positioning, or surgical trauma. Electrophysiologic studies showed underlying diabetic neuropathy with severe multifocal neuropathy distal to the grafts. Digital pressure indices were reduced but there was no critical ischemia. In three cases ischemia was completely corrected with improvement in one. One patient had proximal balloon angioplasty with no improvement and of the two untreated patients, one improved slightly. Ischemic monomelic neuropathy is a rare but disabling complication of dialysis access in diabetic uremic patients. Its occurrence is unpredictable and diagnostic delay is common. Correction of ischemia is indicated but usually does not improve the neuropathy. Prevention requires further research to more accurately characterize the patients at risk.Presented at the Twelfth Annual Meeting of the Southern California Vascular Surgical Society, Coronado, Calif., September 17–19, 1993.