BETA-ENDORPHIN INFUSION FAILS TO MODULATE THE HORMONAL AND METABOLIC RESPONSE TO SURGERY

The effects of an i.v. infusion of synthetic human beta-endorphin on the hormonal, metabolic and cardiovascular responses to surgery were investigated in female patients undergoing pelvic surgery. A beta-endorphin infusion (2 micrograms/kg as a bolus at induction of anaesthesia + 10 micrograms/kg/h for the first hour of surgery) increased plasma beta-endorphin immunoreactivity to values at least 100-fold greater than those seen during surgery in a control group of patients. In spite of this massive increase the only significant findings were a transient augmentation of the expected hyperglycaemic response and increased plasma glucagon values. There were no significant changes in ACTH, GH, insulin and cortisol secretion, in blood concentrations of lactate or glycerol, or in cardiovascular variables. Complete dissociation between plasma and cerebrospinal fluid concentrations of beta-endorphin was found even when plasma values exceeded 10,000 pmol/l in the presence of anaesthesia and surgery. These results show that the increase in circulating beta-endorphin immunoreactivity associated with clinical stress states are unlikely to modulate the associated hormonal, metabolic and cardiovascular changes.     

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Pig livers were cooled in situ by portal vein infusion with Tis-u-sol, and were then excised, rewarmed, and perfused in an isolated circuit with diluted autologous blood. The temperature of the cooling fluid was 10°C in one group and 17° C in the other. Bile flow and brom-sulphllialein excretion in the bile were measured over a 90-minute period of perfusion at 38° C. The total bile flow and bromsulphthalein excretion were not significantly different in the two groups. However, during the first 30 minutes of perfusion there was a significantly lower bile flow and bromsulphthalein excretion in the bile in the livers cooled to 10° C. The results demonstrated a significant delay in the return of excretory function, and this may be relevant in the choice of methods for preparation of livers for clinical liver perfusion or transplantation.     

Stochastic models for systems of interacting ion channels

Email: fgb{at}maths.nott.ac.ukEmail: milne{at}maths.uwa.edu.auEmail: yeo{at}prodigal.murdoch.edu.au We consider a variety of Markov based models for systems ofion channels exhibiting dependence between channels. It is shownhow many useful properties which may be calculated for an aggregatedsingle-channel model, or a system of independent channels, canbe extended to various types of interacting channel systems.Key structure and results from the theory of aggregated Markovprocesses are summarized in a convenient matrix form. Theseare then applied to the superposition of independent and dependentchannels, including a patch of channels in a random environment,and a system of channels with spatial interactions. Calculationsbased on the resultant matrix expressions and intensity argumentscan be implemented straightforwardly in a matrix-oriented packagesuch as Matlab. The role of reversibility is also studied. Anumber of examples illustrate the strengths of the methods andenable numerical comparisons between the different types ofsystems.     

Aplasia of the First and Second Branchial Arches

Woon, K. Y. and Tan, K. L. (1979). Aust. Paediatr. J., 15, 275–277. Aplasia of the first and second branchial arches. A case with the very rare syndrome of otocephaly is reported. It is possible to diagnose this condition in-utero by radiography. Since this is a lethal condition, remedial action can be taken in early pregnancy.     

Prevalence of Persistent Cough During Long-term Enalapril Treatment: Controlled Study Versus Nifedipine

The prevalence and severity of cough during long-term enalapriltreatment were examined by comparing a cohort of 136 hypertensivepatients who started treatment with enalapril with consecutiveage and sex-matched patients who commenced nifedipine therapyduring the same period. Cough and other symptoms were assessedby a questionnaire designed to avoid bias towards reportingcough. After a mean of 27 months' treatment patients on enalaprilhad an excess of persistent cough (16 per cent, 95 per centCI 7–25, p < 0.01), voice change (14 per cent, 95 percent CI 2–27, p < 0.05) and sore throat (10 per cent,95 per cent CI –0.1 to 20.3 per cent, p < 0.01) whencompared to nifedipine-treated patients. The cough was usuallydry, moderate or severe, paroxysmal, and troublesome at night.Cough tended to be more common in women (23 per cent vs. 7.2per cent), non-smokers, and at higher doses of enalapril, butwas not related to age, duration of treatment, or chronic respiratorydisease. Dry cough commonly persists as a troublesome side-effectduring long-term enalapril treatment, and is often associatedwith voice change and sore throat.     

颧部整形的治疗进展

面部轮廓整形目前在整形外科手术中占有越来越大的比例,中面部作为全脸的中心位置,是面部轮廓整形的重点区域,而颧部整形对于面部轮廓的改善有着很重要的作用。颧骨形态特殊,四突、三面、五缘,位置表浅体表投影明显,是面颧部凸起的重要结构,根据解剖学的研究在术前对患者进行三维CT成像测量,分析颧骨形态及手术方案范围,根据手术目的选择相对应的标记点,从而决定手术达到的预期效果及左右对称性有着非常重要作用。颧骨手术包括颧骨后缩的注射填充和假体填充,颧骨肥大的不同截骨手术,口内入路L型截骨术、冠状切口入路双侧截骨术。颧骨手术并发症较少,常见的如血肿、神经损伤、面部不对称及面部软组织松弛下垂等。     

Hypoxia augments cytokine (transforming growth factor-beta (TGF-β) and IL-1)-induced vascular endothelial growth factor secretion by human synovial fibroblasts

Vascular endothelial growth factor (VEGF) is abundant in synovium and synovial fluids, where it probably contributes to vascular permeability and angiogenesis in arthritic joints. To investigate the probable sources of VEGF in synovium, we compared the ability of several cytokines (TGF-β, platelet-derived growth factor (PDGF), IL-1, tumour necrosis factor (TNF), basic fibroblast growth factor (bFGF) that are associated with arthritis and angiogenesis, to stimulate secretion of VEGF protein by human synovial fibroblasts. TGF-β was the strongest inducer of VEGF secretion; six times more VEGF was secreted when cells were stimulated by TGF-β than when stimulated by PDGF or IL-1 for 24 h. TNF-α and bFGF did not stimulate any secretion of VEGF. The stimulatory effects of TGF-β and IL-1 on VEGF secretion were additive. Hypoxic culture alone also stimulated VEGF secretion, but more importantly, hypoxic culture conditions doubled the rate of VEGF secretion stimulated by the cytokines TGF-β and IL-1. When dermal and synovial fibroblasts were stimulated identically by hypoxia and cytokines (TGF-β and IL-1), synovial fibroblasts secreted four times more VEGF than did dermal fibroblasts. Thus in rheumatoid arthritis, the capacity of synovial fibroblasts in the hypoxic environment to secrete large amounts of VEGF in response to cytokines such as TGF-β probably contributes significantly to angiogenesis in the synovium.     

A case of hydroa vacciniforme with unusual ear mutilation

A 22 year-old man visited our department with a 18-year-history of recurrent vesicular eruption on his skin when exposed to the sun. History revealed that the skin lesions developed as vesicles at first, then over the next several days, they formed crusts and healed with scarring. We were able to induce skin lesions by a repetitive UV-A provocation test. By the clinical and histologic features of the induced lesions, the case was diagnosed as hydroa vacciniforme (HV). However, no vesicular lesions were found on physical examination. Instead, in addition to varioliform scarring, we found various unusual clinical manifestations: burn-like lesions and crusts, flexion contracture of the digitum, and ear lobe mutilation. The ear lobe mutilation, which had not been reported previously in HV, was especially interesting.