Per‐oral transgastric abdominal surgery

Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges.     

Plasma Ratios of Tryptophan and Tyrosine to Other Large Neutral Amino Acids in Manic-Depressive Patients

Abstract: The plasma ratio of each neutral amino acid (tryptophan (TRP), tyrosine (TYR), valine, isoleucine, leucine (LEU) or phenylalanine) to the sum of the other neutral amino acids was measured in 16 : manic and 14 : depressed patients. In the manics, there was a correlation between the psychomotor activity and the plasma TRP and LEU ratios. In the depressives, the depressed mood, retardation and global severity were correlated with the TRP ratio. The zotepine responders showed an increase in the TRP ratio after treatment. In the mianserin responders, the TYR ratio, which was high before the treatment, decreased to the normal range after the treatment. But, the plasma amino acid ratios remained unchanged in the patients treated with lithium carbonate or amitriptyhe. These results suggest that, in manic-depressive illness, there might be abnormalities in the metabolism of neutral amino acids, mainly of TRP and TYR, and that the plasma TRP and TYR ratios might be important indicators for determining the efflcacy of some drugs.     

Pharmacokinetics of intravenous N-acetylcysteine in pre-term new-born infants

Background: Reactive oxygen species have been considered to play a role in several clinical complications in pre-term infants. The aim of this study was to determine the pharmacokinetics of intravenous N-acetylcysteine in pre-term neonates. This information is needed to evaluate the use of N-acetylcysteine as an antioxidant in this patient group. Methods: N-acetylcysteine was infused intravenously in ten patients (gestational age 24.9–31.0 weeks, weight 500–1384 g) for 24 h (3.4–4.6 mg/kg/h), starting 2.0–11.2 h from birth (study I) and in six patients (gestational age 25.9–29.7 weeks, weight 520–1335 g) for 6 days (0.3–1.3 mg/kg/h), starting at the age of 24 h (study II). Arterial plasma N-acetylcysteine and cyst(e)ine concentrations were determined from timed samples taken during (study I and II) and after (study I) the N-acetylcysteine infusion. Results: In study I, the mean elimination half-life of N-acetylcysteine was 11 h (range 7.8–15.2 h). The mean plasma clearance of N-acetylcysteine was 37 ml/kg/h (range 13–62 ml/kg/h) and the mean volume of distribution was 573 ml/kg (range 167–1010 ml/kg). The plasma clearance and volume of distribution correlated with weight (r = 0.81, P < 0.01, and r = 0.78, P < 0.01, respectively) and with gestational age (r = 0.71, P < 0.05, and r = 0.64, P < 0.05, respectively). In study II, the steady-state concentration of N-acetylcysteine was reached in 2–3 days in five of six patients during a constant infusion. Conclusions: The pharmacokinetics of N-acetylcysteine in pre-term infants depend markedly on weight and gestational age. The elimination of N-acetylcysteine is much slower in pre-term new-borns than in adults. Received: 12 April 1999 / Accepted in revised form: 18 August 1999     

Takayasu''s aortitis with renovascular hypertension

We report a case of Takayasu's disease with severe renovascular hypertension in a girl from Eritrea. In the "burn-out" phase after the erythrocyte sedimentation rate had normalized, reconstructive vascular surgery was performed as further progression of the disease seemed unlikely. However, probably due to her growth, the graft rotated and a second operation was successfully performed.     

马来酸曲美布汀治疗肠易激综合征对比研究

目的探讨马来酸曲美布汀对肠易激综合征的治疗效果。方法将诊断为肠易激综合征（IBS）的97例患者随机分成试验组（47例）和对照组（50例），试验组给予马来酸曲美布汀，对照组使用复合维生素B作为安慰剂，两组疗程均为6周，治疗期间均停用其他药物，分别于治疗前及治疗的第2、4、6周及随访8、12周末进行症状评价及评分。结果试验组治疗后积分明显下降，治疗前后比较差异有非常显著性（P〈0．01）；对照组积分下降不明显，治疗前后比较差异无显著性（P〉0．05）；治疗4周后两组间比较，试验组积分下降较对照组明显，差异有非常显著性（P〈0．01）；治疗后两组疗效比较，试验组在2周后有效率达34％，8周和12周时分别达到83％和82％，疗效明显高于对照组，差异有非常显著性（P〈0．01）。结论马来酸曲美布汀对难治性功能性消化不良具有良好的治疗作用和安全性。     

Relative roles of inhibin B and sex steroids in the negative feedback regulation of follicle-stimulating hormone in men across the full spectrum of seminiferous epithelium function

CONTEXT AND OBJECTIVE: Our aim was to explore the relative roles of gonadal sex steroids and inhibin B in the regulation of FSH across a spectrum of seminiferous epithelium function. SUBJECTS: The study included three groups: group I, healthy men (n = 31); group II, men with idiopathic hypogonadotropic hypogonadism receiving pulsatile GnRH (n = 12) selected to represent a spectrum of seminiferous tubular development, testicular size, and baseline inhibin B levels; and group III, men with functional anorchia (n = 3) receiving testosterone replacement. DESIGN: Subjects were studied before and after 3 d of acute sex steroid withdrawal. SETTING: The study was conducted at the Mallinckrodt General Clinical Research Center of Massachusetts General Hospital. INTERVENTIONS: Acute biochemical castration was achieved using high-dose ketoconazole (groups I and II) or withdrawal of androgen therapy (group III). MAIN OUTCOME MEASURES: The relationship between FSH and inhibin B in both normal and castrate sex steroid milieu was measured. RESULTS: In both normal and castrate sex steroid milieus, there was a negative relationship between inhibin B and FSH, best described by a logarithmic model. Acute biochemical castration resulted in the most dramatic increases in FSH in men with the lowest baseline inhibin B levels. CONCLUSIONS: We came to the following conclusions: 1) in the human male, inhibin B is the principal gonadal feedback regulator of FSH secretion unless seminiferous tubular function is severely compromised, and a logarithmic model best describes this relationship; and 2) sex steroid inhibition of FSH secretion is most apparent when serum inhibin B levels fall well below the normal range.     

Inhibins in childhood and puberty

Inhibin is a heterodimeric glycoprotein that consists of an alpha-subunit linked to either a betaA subunit (inhibin A) or to a betaB subunit (inhibin B) and it exists in at least six different isoforms. These isoforms can not be measured separately by immunoassays. In boys, serum inhibin B levels change in concert with the increase in gonadotrophins. Associated with the postnatal activation of gonadotrophin secretion, the early inhibin B secretion is sustained until the age of 18-24 months; thereafter serum concentrations subside. In boys, between Tanner stages G1 and G2, serum inhibin B concentration again increases, but then plateaus. Inhibin A levels in human males are below the detection limit, but in girls, during the postnatal activation of gonadotrophin secretion, both serum inhibin A and inhibin B concentrations are measurable. Serum inhibin B levels correlate positively with age several years before the clinical onset of puberty, suggesting increasing follicular activity in late prepuberty. During female puberty, the inhibin B level increases from Tanner stage B1 through stage B3, suggesting high follicular activity before the development of ovulatory menstrual cycles, but serum inhibin A levels become measurable later in puberty, in agreement with the idea that inhibin A is mainly produced by the corpus luteum.     

Acute Kidney Injury Following Aortic Valve Replacement in Patients Without Chronic Kidney Disease

BackgroundThe data on acute kidney injury (AKI) in patients without chronic kidney disease (CKD) after transcatheter aortic valve replacement (TAVR) are limited. The study sought to compare the incidence of AKI and its impact on 5-year mortality after TAVR and surgical aortic valve replacement (SAVR) in patients without CKD.MethodsThis registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m². AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. For sensitivity analysis, propensity-score matching between TAVR and SAVR was performed.ResultsThe study included 4555 consecutive patients (TAVR, n = 1215 and SAVR, n = 3340) without CKD. Propensity-score matching identified 542 pairs. Patients who underwent TAVR had a significantly lower incidence of AKI in comparison to those who underwent SAVR (unmatched 4.7% vs 16.4%, P < 0.001, multivariable analysis: odds ratio, 0.29, 95% confidence interval [CI], 0.20-0.41; matched 5.9% vs 19.0%, P < 0.001). Patients with AKI had significantly increased 5-year mortality compared with those without AKI (unmatched 36.0% vs 19.1%, log-rank P < 0.001; matched 36.3% vs 24.0%, log-rank P < 0.001). The adjusted hazard ratios for 5-year mortality were 1.58 (95% CI, 1.20-2.08) for AKI grade 1, 3.27 (95% CI, 2.09-5.06) for grade 2, and 4.82 (95% CI, 2.93-8.04) for grade 3.ConclusionsTAVR in patients without CKD was associated with a significantly less frequent incidence of AKI compared with SAVR. AKI significantly increased the risk of 5-year mortality after either TAVR or SAVR, and increasing severity of AKI was incrementally associated with 5-year mortality.