Filtration procedures supplemented with mitomycin C in the management of childhood glaucoma

AIMS: To evaluate the outcome of filtering procedures supplemented with mitomycin C in children with glaucoma. METHODS: All patients aged 17 or younger with glaucoma who underwent filtering surgery supplemented with mitomycin C at a tertiary care centre (n = 21) during a 5 year interval (1992 and 1996) were included. One eye for each patient was entered into the analysis. The postoperative intraocular pressure (IOP), use of antiglaucoma medications, clinical stability of glaucoma, complications, and visual acuity were retrospectively evaluated. Kaplan-Meier survival curves were used to estimate the probability of success. RESULTS: At the time of surgery mean age was 5.7 (SD 5.0) years. The most common diagnoses were trabeculodysgenesis (n = 6) and aphakic glaucoma (n = 8). Mean IOP before surgery was 35.7 (10.5) mm Hg. Average length of follow up was 18.6 (14.7) months. The probability of having IOP less than 21 mm Hg with no antiglaucoma medications and with clinically stable glaucoma 1 year after surgery was 76.9% in phakic eyes (n = 13) and 0% in aphakic eyes (n = 8). A phakic patient with Sturge-Weber's syndrome had choroidal effusion after surgery that resolved spontaneously. In the aphakic group one patient had retinal detachment and another developed an encapsulated bleb. Visual acuity deteriorated in one patient. CONCLUSION: A guarded filtration procedure with mitomycin C is relatively successful in phakic children with glaucoma, but unsuccessful in aphakic ones.     

Effective use of medical-scientific Internet resources

Hintergrund: Das Medium Internet ist nicht hierarchisch strukturiert und unterscheidet sich daher von herk?mmlichen Wissensquellen. Die ansteigende Zahl medizinisch-wissenschaftlicher Webseiten bietet dem Augenarzt umfangreiche, jedoch nicht immer leicht zu erschlie?ende Informations- und Weiterbildungsm?glichkeiten. Material und Methode: Die Effektivit?t einer Internet-Recherche h?ngt vom Wissenstand über vorhandene Suchstrategien ab. Es werden Suchsysteme (Search engines, Kataloge, Datenbanken, Indizes) dargestellt sowie Hinweise für deren effektive Nutzung (Metasearch, Anwendung von Boolean-Operatoren, Wortgruppen-Suche) gegeben. Die Effizienz der Suche wird anhand konkreter Ergebnisse, deren Aktualit?t und der Anwenderfreundlichkeit der verwendeten Systeme bewertet. Neue, zukunftsweisende Applikationen wie SemioMap und Intelligent Agents werden vorgestellt. Ergebnisse und Schlu?folgerung: Bei Anwendung effektiver Suchstrategien stellt das Internet bereits heutzutage eine einfache und schnell zu nutzende Informationsquelle für den Arzt und Wissenschaftler dar. Die verfügbaren medizinisch-wissenschaftlichen Ressourcen leisten zunehmend aktuelle und praxisbezogene Beitr?ge zu fachspezifischer Weiterbildung und zukunftsorientierter Forschung.      

Orbital surgery – perioperative problems and results

Fragestellung: Orbitotomien nehmen innerhalb der Ophthalmochirurgie auf Grund der involvierten anatomischen Strukturen und des daraus resultierenden Spektrums m?glicher perioperativer Probleme eine Sonderstellung ein. Um einen überblick über die Art und H?ufigkeit intra- und postoperativer Probleme bei Orbitotomien zu erhalten, führten wir eine retrospektive Auswertung an unserer Klinik durchgeführter Orbitotomien durch. Patienten und Methode: Es wurden 48 Orbitotomien bei 46 Patienten berücksichtigt, die zwischen 08/1995 und 02/1998 operiert wurden. Ergebnisse: Schwerwiegende intraoperative Komplikationen waren mit zwei transfusionspflichtigen Blutungen und einer Liquorfistel selten. Sie wurden interdisziplin?r behandelt. Postoperativ traten vorübergehende funktionelle St?rungen mit guter Rückbildungstendenz wie Visusminderungen (35 %), Motilit?tsst?rungen mit oder ohne Doppelbildwahrnehmung (20 %) und Lidfehlstellungen auf. Ihnen liegt v. a. die postoperative ?dem- und H?matombildung zugrunde. Persistierende Funktionseinschr?nkungen waren dagegen selten (10 %). Schlu?folgerung: Unsere Untersuchung zeigt, da? perioperativ bei Orbitotomien v. a. vorübergehende funktionelle Einschr?nkungen auftreten, die sich rasch zurückbilden. Schwere Komplikationen sind dagegen selten, treten v. a. intraoperativ auf und k?nnen eine interdisziplin?re Therapie erfordern.      

丝裂霉素C在青光眼滤过性手术中的应用

目的通过在青光眼滤过性手术中应用丝裂霉素Ｃ（ＭＭＣ）的临床疗效分析,寻求提高青光眼手术疗效的途径。方法１９９４～１９９５年本院２６例２９眼各种类型青光眼施行小梁切除术的病例,术中应用ＭＭＣ,对其术后疗效进行临床观察及随访。结果本组青光眼术后９６％眼压得到有效控制,所有病例术前术后视力不变或增减一行,视野基本保持不变,随访６～１２个月眼压仍保持正常者７２％。讨论ＭＭＣ可有效抑制术后成纤维细胞增生,只需术中一次性用药,不引起眼内组织损害,优于其他抗代谢药物。对年龄在５０岁以下青光眼患者,普遍宜在滤过性手术中应用ＭＭＣ,以抑制术后瘢痕形成,提高抗青光眼手术的成功率。     

Early and delayed cardioprotection by heat stress is mediated by calcitonin gene-related peptide

Brief ischaemia or heat stress protects the myocardium against ischaemia-reperfusion injury. Heat stimulus evokes release of sensory nerve transmitters, including calcitonin gene-related peptide (CGRP). Since CGRP has been shown to play an important role in the mediation of ischaemic preconditioning, the present study examined whether early or delayed preconditioning induced by retrograde hyperthermic perfusion in vitro or by whole-body hyperthemia in vivo also involves endogenous CGRP. Isolated rat hearts were perfused in the Langendorff mode and subjected to 30 min global ischaemia and 30 min reperfusion. Heart rate, coronary flow, left ventricular pressure and its first derivatives (±dp/dt) were recorded and the CGRP-like immunoreactivity (CGRP-LI) content and the release of creatine kinase (CK) during reperfusion were measured. Retrograde hyperthermic perfusion (42 °C) for 5 min improved the recovery of cardiac function, decreased the release of CK and elevated the content of CGRP-LI in the coronary effluent. CGRP_8–37 (10^–7 mol/l), a selective CGRP receptor antagonist, abolished the cardioprotection by heat stress. Pretreatment with capsaicin (50 mg/kg s.c.), which specifically depletes sensory nerve transmitter content, abolished both the cardioprotection and the increased release of CGRP-LI. Whole-body hyperthermia (42 °C for 15 min) caused an increase in the plasma concentration of CGRP-LI. Early or delayed protection was shown in the hearts obtained from the animals subjected to whole-body hyperthermia 10 min or 48 h before the experiments. The early or delayed protection by heat stress was also abolished by pretreatment with capsaicin. The present study suggests that, in the rat, the early and delayed cardioprotection induced by heat stress involves endogenous CGRP. Received: 31 December 1998 / Accepted: 6 April 1999     

Pindolol binding to 5-HT1A receptors in the human brain confirmed with positron emission tomography

The augmentation effect of (–)pindolol as used in combination with SSRI to treat major depression has been ascribed to blocking of dorsal raphe nucleus cell body 5-HT autoreceptors. In this study, the radioligand [carbonyl-¹¹C]WAY-100635 and positron emission tomography were used to establish whether pindolol at a clinical dose level (10 mg s.o.d.) occupies 5-HT_1A receptors in the human brain in vivo. Three healthy males were recruited and each subject was used as his own control. The 5-HT_1A receptor occupancy was calculated for the frontal and temporal cortex and the raphe nuclei, using and a ratio analysis with the cerebellar cortex as the reference region. Maximal pindolol plasma concentration was reached within 3 h after drug administration. Two hours after pindolol administration, the regional 5-HT_1A receptor occupancy was within the range 7–21% in the three subjects. The study confirms that the 5-HT_1A-receptor may be a clinically significant target for pindolol. Received: 8 March 1999 / Final version: 15 March 1999     

Mechanism of tolerance development to 2,5-dimethoxy-4-iodoamphetamine in rats: down-regulation of the 5-HT2A, but not 5-HT2C, receptor

  Rationale: Defining the mechanism of tolerance development to hallucinogenic drugs will help to explain their mechanism of action. Objectives: The present study was conducted to determine first, if tolerance develops to the discriminative stimulus (DS) properties of the hallucinogen, 2,5 dimethoxy-4-iodo-amphetamine (DOI) and second, the mechanism mediating tolerance. Methods: Rats were trained to discriminate 0.75 mg/kg DOI from saline on a concurrent VI-30-min schedule of reinforcement with a 15-min time-out for incorrect responses. To evaluate tolerance development, rats were assigned to one of four groups and treated with either chronic saline or chronic DOI. Prior to chronic treatment, two groups were tested for choice behavior following vehicle administration while the remaining two groups were tested following the administration of 0.375 mg/kg DOI. One group from each pre-test condition was injected with either saline or DOI (1 mg/kg) for 8 days. Twenty-four hours after the last chronic injection the pre-test treatments were replicated. Using receptor autoradiography, the density of 5-HT_2A and 5-HT_2C receptors was measured in independent groups of rats that had received identical treatment conditions. Results: Animals receiving chronic DOI showed a 60% decrease in DOI lever responding (from 100% to 40%) when tested on 0.375 mg/kg DOI, while animals receiving chronic saline showed no change in percent choice (100%) on the DOI lever. Significant changes in binding were observed in 5-HT_2A receptors but not 5-HT_2C receptors. The results of tests with antagonists were consistent with the changes in binding. Conclusions: These results suggest that behavioral tolerance to DOI reflects neuroadaptive changes in 5-HT_2A receptors. Received: 17 July 1998 / Final version: 19 January 1999     

RP—HPLC法对不同产地蝙蝠葛几种主要生物碱的测定

目的：研究不同产地蝙蝠葛几种主要生物碱在质与量上的区别。方法：采用有机溶剂提取生药,应用ＲＰ－ＨＰＬＣ方法在东北产和咸宁产蝙蝠葛根茎中几种主要脂溶性生物碱定性定量测定。结果：东北生一最高的生物碱前３位依次是蝙蝠葛苏林碱、蝙蝠碱和ｇｕａｔｔｅｇａｕｎｅｒｉｎｅ;而咸宁药材则为蝙蝠葛碱、蝙蝠葛诺林碱及蝙蝠葛新诺林碱,不含蝙蝠葛苏林碱。结论：不同产地蝙蝠葛药材所含生物碱在质和量两方面均有显著差异。     

PKC activators stimulate H+ conductance in chicken enterocytes

Chicken enterocytes present a H⁺-conducting pathway involved in the recovery of intracellular pH (pH_i) from an acid load. In the current study we have tested the effect of protein kinase C (PKC) activators on the rate of proton efflux through the H⁺-conducting pathway. The rate of proton efflux was increased by the addition of 1,2-dioctanoyl-rac-glycerol (DOG) or phorbol 12-myristate 13-acetate (PMA), but it was not affected by the addition of the inactive phorbol ester analogue, 4-phorbol 12, 13-didecanoate. DOG stimulated the process in a dose-dependent manner with a half-maximal effect at 45 M. Staurosporine and Zn²⁺ prevented the DOG-dependent increase in the rate of proton efflux. The rate of proton efflux was affected by the pH_i and DOG shifted this relationship upward and to the right. These results suggest that the proton-conducting pathway is regulated by PKC.     

IL-1β and TNF-α produced by peripheral blood mononuclear cells before and during interferon therapy in patients with chronic hepatitis C

We investigated the spontaneous and phytohemagglutinin-stimulated production of interleukin-1 (IL-1) and tumor necrosis factor- (TNF-) by peripheral blood mononuclear cells in patients with chronic hepatitis C during treatment with interferon- (IFN-). Spontaneous productions of these were significantly higher in patients with chronic hepatitis C than in healthy subjects. For patients prescribed interferon, stimulated production of TNF- was significantly higher in complete responders than in partial responders, but the differences were small between the other cytokine levels and outcome of IFN treatment. Spontaneous production of these cytokines was higher in patients with genotype III with complete response than in genotype III patients with a partial response, but this was not the case in patients with genotype II. There was a negative correlation between these cytokines and histological activity index. Spontaneous production of cytokines was decreased only in complete responders after the administration of interferon. These data suggest that the elevated production of cytokines in patients with chronic hepatitis C may be due to host response to the virus, and monitoring cytokines along with alanine aminotransferase and hepatitis C virus RNA during treatment may provide more precise information of the effectiveness of therapy.