Placement of the Dumon stent using a flexible bronchofiberscope via tracheostomy

In this paper, we report on a new technique of Dumon stent placement using a flexible bronchofiberscope. This procedure was used to insert Dumon stents in two bronchial obstruction and two bronchofistula cases. The stenting technique described here can be used through either a tracheostoma or the oral cavity; it presents a very straightforward and safe procedure that does not require the use of a rigid bronchoscope.     

Hemodynamic and autonomic effects of intravenous saterinone in patients with chronic heart failure

In this study, the hemodynamic and neurohumoral/autonomic effects of intravenous saterinone (a selective phosphodiesterase type III inhibitor, with additional alpha 1-blocking properties) were evaluated. In a double-blind, placebo-controlled design, 36 patients with moderate to severe heart failure were studied (saterinone, n = 24; placebo, n = 12). Invasive hemodynamic measurements, by using right-heart catheterization, were performed, as well as measurement of plasma neurohormones and analysis of heart rate variability (HRV), to study drug influences on neurohumoral activation and autonomic tone. Systemic vascular resistance significantly decreased during saterinone infusion, accompanied by a decrease in systemic blood pressure (both p values < 0.05) and an increase in heart rate (p = 0.05). Filling pressures also decreased during saterinone, but this was statistically significant only for pulmonary capillary wedge pressure, whereas the cardiac index remained unaffected. Plasma neurohormones (norepinephrine, epinephrine, and renin activity) were not significantly influenced by saterinone. HRV analysis revealed no significant effect of saterinone on autonomic tone. These results suggest that intravenous saterinone has a significant vasodilating effect in patients with moderate to severe chronic heart failure (CHF), without exerting an adverse effect on the autonomic nervous system, as demonstrated by assessment of plasma neurohormones and HRV analysis.     

Complexity and frequency hierarchies in the catfish retina

The intricate connectivity and interactions between neurons in the vertebrate retina have made their individual roles in signal processing very difficult to elucidate. We have used a recently developed mathematical tool, fast orthogonal search (FOS), to probe the catfish outer (distal) and inner (proximal) retina, and study the signal processing within. Through FOS, a given waveform can be decomposed into a parsimonious sinusoidal series containing the most significant constituent frequencies. In particular, we examined the light-evoked first-order Wiener kernels of horizontal cells and on-bipolar cells, and on-off, off- and on-amacrine and ganglion cells. Here we report a hierarchy (correlation coefficient up to 0.86) in preferred frequency and complexity of response corresponding to the retina's structural hierarchy. In addition, clear differences between on-, on-off and off-cell functional characteristics were detected. For example, the kernel waveform for the on-amacrine cell was found to be more complex and to have a higher preferred frequency than that for the off-amacrine cell. Indeed FOS analysis revealed that both off- (sustained) amacrine and off-ganglion cells exhibit significantly less complexity in their waveforms for signal processing of light input than do the corresponding on- and on-off cells. This shows a clear breakdown in symmetry between on- and off-pathways, and suggests that connections to off-cells may provide fewer or a smaller variety of inputs than those to on- and on-off cells. Many of our new findings can be appreciated by assuming an underlying cascade structure for the retinal information processing. The FOS findings in particular support the following previously advanced hypothesis: the transition in nonlinear processing from on-off amacrine to on- off-amacrine cells is due to high-pass linear filtering. Furthermore, our results indicate that the high-pass filtering is more sharply differentiating for the on-amacrine than for the off-amacrine cell.     

RNA cleavage without hydrolysis. Splitting the catalytic activities of binase with Asn101 and Thr101 mutations

We have developed a model of ischaemia-reperfusion injury in C57BL/6 mice involving ischaemia for 0.5 to 2.5 h with an elastic tourniquet on one hind limb and reperfusion for 24 h, analogous to a well-established model of ischaemia-reperfusion injury in the rat. Viability was assessed in tissue homogenates of the gastrocnemius muscles from the affected and contralateral control limb by a triphenyl tetrazolium chloride dye reaction, measuring the activity of the oxidative mitochondrial enzymes. After 1.5 h ischaemia and 24 h reperfusion, viability in the ischaemic-reperfused limb was 13%, with the control muscle regarded as 100% viable. Significant improvements in viability to 86% (P < 0.05) and 56% (P < 0.05) were achieved, with administration 30 min prior to tourniquet release, of the nitric oxide (NO) synthase inhibitor nitro-L-arginine methyl ester (L-NAME, 30 mg/kg) and the anti-inflammatory glucocorticoid dexamethasone (2.5 mg/kg) respectively, with similar findings in the rat tourniquet model.     

cGMP stimulation of cystic fibrosis transmembrane conductance regulator Cl- channels co-expressed with cGMP-dependent protein kinase type II but not type Ibeta

In order to investigate the involvement of cGMP-dependent protein kinase (cGK) type II in cGMP-provoked intestinal Cl- secretion, cGMP-dependent activation and phosphorylation of cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channels was analyzed after expression of cGK II or cGK Ibeta in intact cells. An intestinal cell line which stably expresses CFTR (IEC-CF7) but contains no detectable endogenous cGK II was infected with a recombinant adenoviral vector containing the cGK II coding region (Ad-cGK II) resulting in co-expression of active cGK II. In these cells, CFTR was activated by membrane-permeant analogs of cGMP or by the cGMP-elevating hormone atrial natriuretic peptide as measured by 125I- efflux assays and whole-cell patch clamp analysis. In contrast, infection with recombinant adenoviruses expressing cGK Ibeta or luciferase did not convey cGMP sensitivity to CFTR in IEC-CF7 cells. Concordant with the activation of CFTR by only cGK II, infection with Ad-cGK II but not Ad-cGK Ibeta enabled cGMP analogs to increase CFTR phosphorylation in intact cells. These and other data provide evidence that endogenous cGK II is a key mediator of cGMP-provoked activation of CFTR in cells where both proteins are co-localized, e. g. intestinal epithelial cells. Furthermore, they demonstrate that neither the soluble cGK Ibeta nor cAMP-dependent protein kinase are able to substitute for cGK II in this cGMP-regulated function.     

Variance components analysis of carotid and femoral intima-media thickness measurements. REGRESS Study Group, Interuniversity Cardiology Institute of The Netherlands, Utrecht, The Netherlands. Regression Growth Evaluation Statin Study

B-mode ultrasound intima-media thickness (IMT) measurements of carotid and femoral arterial walls are used in atherosclerosis studies. In this study, the components contributing to IMT measurement variability in males with coronary artery disease were investigated by means of repeated B-mode ultrasound scans and repeated off-line video image analyses. For statistical analysis, a mixed-model analysis of variance was used. From sonographer data, it was shown that human subjects and their arterial wall segments contributed 75% of the total IMT measurement variability in this population. Inter-sonographer variance contributed 25%. The intra-sonographer variance was negligible (<1%). In off-line image analysis, variance components due to subjects and segments, inter-analyst variance, and residual fluctuation were 88%, < 1% and 11%, respectively. Intra-analyst variance was negligible (<1%). The major source of B-mode ultrasound IMT measurement variability finds its origin in subjects and their arterial walls. Although sonographers proved a lesser source of variability, in comparative studies they should enter a study well trained and should be randomly assigned to subjects. Follow-up examinations should preferably be done by the same sonographer. Off-line image analysis contributed little to IMT measurement variability.     

Promoter/repressor system of Lactobacillus plantarum phage og1e: characterization of the promoters pR49-pR-pL and overproduction of the cro-like protein cng in Escherichia coli

Previous studies have shown that extensive damage to the medial prefrontal cortex (mPFC) of rats causes reversal learning deficits. The mPFC of rats, however, consists of several subareas that are different from each other in both cytoarchitecture and neural connectivity, suggesting a functional dissociation among the mPFC subareas. In the present study, selective lesions of the mPFC of rats were made with a specially designed microknife whose intracranial placement could be controlled stereotaxically. Restricted lesions were made to each of the 3 parts of the mPFC: the anterior cingulate area (AC) (including the medial precentral area, PrCm), the prelimbic area (PL), and the infralimbic area (IL). One week after surgery, rats were trained in an aversively motivated visual discrimination task in a novel rotating T-maze. After reaching the acquisition criterion, rats were trained in a reversal task in the same maze. No difference was found in acquisition between control and mPFC lesioned rats. However, lesions of either the PL or the IL produced a marked deficit in the reversal task. This behavioral deficit was not found in rats with lesions of the AC. The results indicate that the mPFC of rats is not essential for discrimination learning, but that each of the 2 ventral subareas of the mPFC, PL, and IL, plays a critical role in reversal learning.     

Benign postpartum pleural effusion

The conditions of labour appear to favour the development of pleural effusion. The frequency of postpartum pleural effusion was investigated in this study using thoracic ultrasonography. Thirty one postpartum and 22 healthy nonpregnant women of the same age-group were examined, both supine and seated, via an intercostal approach. Seven of the 31 (23%) postpartum women had pleural effusion within 1-24 h of normal delivery. None of the nonpregnant women had pleural effusion. No correlation was found between postpartum pleural effusion and age, weight-gain during pregnancy, duration of labour, use of intravenous fluid, or oxytocin administration. Pleural effusion seems to be a common finding postpartum, but of no clinical significance.     

Phase-IV multicentre clinical study of risperidone in the treatment of outpatients with schizophrenia. The RIS-CAN-3 Study Group

OBJECTIVE: Since most clinical trials of atypical antipsychotics have been conducted in hospitalized patients, a Phase-IV, multicentre, 8-week, open-label, flexible-dose study was performed to assess the efficacy and safety of risperidone in outpatients with schizophrenia. METHOD: Three hundred and thirty patients with a Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) diagnosis of schizophrenia were enrolled at 61 Canadian sites. Upon trial entry, the patients had their neuroleptic and antiparkinsonian drugs discontinued, and treatment with risperidone was initiated at a dose of 2 mg daily, then increased by 2 mg daily on each of the 2 following days until the initial target dose of 6 mg daily was reached on day 3. No further titration was allowed until day 14, after which the dose could be increased or decreased. RESULTS: During the stabilization phase (days 14-56), the dose was unchanged in 44% of the patients, increased in 24%, decreased in 23%, and titrated both up and down in 9% of the patients. In the efficacy-evaluable population (n = 292), treatment with risperidone produced substantial (-26.4) and significant (P = 0.0001) improvement in the total Positive and Negative Syndrome Scale (PANSS) score. At the end of the study (week 8), 85% of patients were classified as clinically improved according to an a priori definition (that is, 20% or more decrease from baseline in total PANSS score). On their last study visit, 75% of patients reported their experience with risperidone as better than their previous neuroleptic therapy. Risperidone was generally well tolerated. The adverse events reported by more than 5% of the patients were insomnia, nausea, headache, somnolence, dizziness, fatigue, anxiety, vomiting, and ejaculation disorder. Seventy-four percent of the reported treatment-related adverse events were recorded during the first 2 weeks of the trial, possibly because of the discontinuation of prior neuroleptic and antiparkinsonian drugs followed by immediate upward titration of risperidone. However, only 8.5% of adverse events were reported to have occurred during week 3, and only 0.8% of adverse events were reported for week 8. Risperidone treatment produced significant improvements over baseline in the incidence and severity of extrapyramidal symptoms (EPS). A slight but statistically significant increase in body weight was observed. CONCLUSIONS: The results of this open-label, Phase-IV trial in a large population of outpatients with schizophrenia found that risperidone was superior to the neuroleptics that patients had previously taken in terms of efficacy and severity of EPS. Our results suggest the use of risperidone at lower doses in outpatients with schizophrenia.