改良Blalock-Taussig分流术在新生儿中的应用

目的：探讨改良Blalock-Taussig分流术在新生儿中的应用。方法：总结20例患危重复杂性紫绀型先天性心脏病的新生儿行急诊锁骨下动脉和肺动脉之间植入人造血管的改良Blalock-Taussig分流术的临床经验。其中男13例，女7例，年龄1－28d，平均9.8d，平均体重3.5kg（2.4-4.6kg）。结果：所有新生儿患者均获得理想的分流量，术后动脉血氧饱和度升为70％－93％（平均86．1％），与术前比较有显著改善（P＜0．05）。11例二期手术前施行心导管检查，均证明人造血管通畅，没有发生人造血管和肺动脉的扭转。2例严重法乐氏四联症伴有肺动脉发育不良，分别在分流术后8和10个月紫绀加重，并发生充血性心力衰竭，1例分流术后4d死于全身感染。结论：改良Blalock-Taussig分流术是新生儿期为缓和危重紫绀型先天性心脏病病情的可选择的术式。     

Effect of the anxiolytic drug buspirone on prolactin and corticosterone secretion in stressed and unstressed rats

Buspirone is an atypical anxiolytic drug that exerts its action at a receptor site other than the GABA-benzodiazepine-chloride ionophore complex. The present study examined the effect of buspirone on plasma prolactin and corticosterone levels in both control and stressed rats. In unstressed rats, buspirone produced dose-dependent increases in plasma prolactin and corticosterone levels. The minimal doses of buspirone which led to significant elevations in plasma prolactin and corticosterone levels were 1.0 and 2.0 mg/kg (IP), respectively. The effect of buspirone on both hormones was maximal 30 minutes after injection. The plasma levels of prolactin and corticosterone were significantly elevated in rats that were stressed using a conditioned fear paradigm. Buspirone produced a dose-dependent attenuation of the stress-induced increase in prolactin secretion. The stress-induced increase in corticosterone secretion was inhibited by the 0.5 mg/kg (IP) dose but not by the 2.0 mg/kg (IP) dose of buspirone, which increased corticosterone secretion both in stressed and unstressed rats. These data suggest that the effect of buspirone on plasma prolactin and corticosterone levels may be mediated by two different mechanisms of action.     

Enabling the return-to-work process among people with affective disorders: A multiple-case study

Background: The Individual Enabling and Support (IES) model is an adapted, supported employment program developed to meet motivational, cognitive and time-use needs of people with affective disorders. Vocational programs for this target group have been developed but more knowledge is needed about the important characteristics and perceived usefulness of the programs. The aim of this study was to illustrate the IES model and process from multiple perspectives.

Methods: Five participants were included in this multiple-case study. The material comprised interviews with participants, intervention documents, memos and interviews with employment specialists. Within and cross-case analyzes and an analytical generalization were performed.

Results: The cases illustrated different IES processes, and the theme; Enabling engagement in return to work (RTW) was formulated. Continuous support from the employment specialist and a focus on personal resources and motivation were essential to overcome low self-confidence regarding RTW. Motivational, cognitive and time-use strategies gave an opportunity to learn new behavior and coping strategies for job seeking, getting employed and working.

Conclusion: Providing a combination of these strategies integrated with supported employment could promote self-efficacy and engagement in the RTW process among people on sick leave due to an affective disorder.     

Effect of small bowel resection on the intestinal surface acid microclimate in the rat

The effect of extensive (65%) proximal and middle small bowel resection on the intestinal surface acid microclimate (ISAM) of the remaining ileum in the rat was examined and the results were compared to those of sham-operated rats. ISAM pH measurements were performed in vivo using a pH microelectrode; incubation was performed in Krebs-Ringer phosphate buffer (pH 7.40 +/- 0.02). In the resected rats, ISAM pH of 6.03 +/- 0.07 and 7.22 +/- 0.03 were recorded in the proximal and distal part of the remaining ileum, respectively. In the sham-operated rats, ISAM pH of 6.04 +/- 0.07, 6.98 +/- 0.03 and 7.28 +/- 0.02 were recorded in the proximal jejunum and in the proximal and distal part of the corresponding ileal segment. ISAM pH was significantly lower (p less than 0.01) in the proximal part of the remaining ileum of the resected rats as compared to the corresponding part in the sham-operated rats but was similar in distal ileum. In fact, the ISAM pH of the proximal part of the remaining ileum of resected rats was as acidic as that of the jejunum of the sham-operated rats. These results clearly demonstrate that adaptation in the ISAM occurs in the remaining ileum following extensive resection of proximal and middle small intestine.     

Mapping of the hepatitis B virus attachment site by use of infection-inhibiting preS1 lipopeptides and tupaia hepatocytes

BACKGROUND & AIMS: Studies on the early steps in the life cycle of hepatitis B virus have been hampered by the lack of readily available target cells. In this study, we mapped a defined virus attachment site to primary hepatocytes that is essential for infection. METHODS: We used purified virus particles from human carrier plasma as an inoculum and primary cultures of tupaia hepatocytes as susceptible target cells and studied the inhibitory effect of amino-terminally acylated preS1-derived lipopeptides on infection interference. RESULTS: Infectivity of virus could be blocked efficiently in this system by amino-terminally acylated peptides containing amino acids 2-18 from the preS1 domain. The addition of amino acids 28-48 enhanced the inhibitory capacity, whereas amino acids 49-78 did not contribute to inhibition. Myristoylated preS1 peptides 2-48 bound strongly to tupaia hepatocytes but not to nonhepatic cells or rodent hepatocytes and thereby inhibited infection even at concentrations of 1 nmol/L completely. Particles consisting only of the small hepatitis B surface protein-the active component of current hepatitis B vaccines-did not bind at all to tupaia hepatocytes, but the addition of the preS1 domain to the particles allowed binding. CONCLUSIONS: The preS1 sequence 2-48 mediates attachment of the virus to its target cells, whereas the small surface protein seems to be involved in other steps. These findings indicate that the current subunit hepatitis B vaccines may be improved by the addition of distinct preS1 epitopes. Moreover, preS1 lipopeptides are promising candidates for specific antiviral therapy against hepatitis B infections.     

An overview of the endocrinology of skeletal muscle.

Endocrine regulation of the balance between skeletal muscle anabolism and catabolism has been investigated extensively. Factors determining whether hormones exert anabolic or catabolic influences are multifaceted and often unclear. Testosterone, growth hormone, insulin and insulin-like growth factor-I have complex anabolic effects, some of which have only recently been elucidated, and are important regulators of muscle remodeling, whereas glucocorticoids have direct catabolic effects and induce muscle protein loss. The effects of estrogen are poorly understood and warrant further study. We review recent literature and evaluate the hormones driving skeletal muscle anabolism and catabolism, which ultimately dictate the endocrinology and metabolism of skeletal muscle in humans. Understanding hormonal regulation of skeletal muscle remodeling might facilitate development of improved hormone-mediated therapies for muscle wasting conditions.     

Vagotomy and gallbladder function

The effect of vagotomy on gallbladder function was investigated in a clinical and experimental study. In the clinical study both the size of the gallbladder and its capacity to respond to cholecystokinin were evaluated radiologically before and after vagotomy. In studies in the rabbit, both the immediate effect of vagotomy on the gallbladder and the effect of varying doses of cholecystokinin on gallbladder pressure were studied before and after vagotomy. In studies in the cat the long-term effect of vagotomy was studied with respect to the histology of the gallbladder and the composition of bile.The clinical investigation showed that vagotomy was followed by a significant increase in the volume of the gallbladder and that the effect of the cholecystokinin on the gallbladder remained unchanged after vagotomy. In experiments in the rabbit it was found that cholecystokinin in a dose of 1 unit/kg body weight exerted a somewhat lesser effect on gallbladder pressure after vagotomy than before, while after vagotomy a dose, approximately four times greater, resulted in a stronger gallbladder response. Further, the experiments showed that the chemical composition of the bile seemed to be altered after vagotomy, while the gallbladder remained histologically essentially unchanged.