Paradoxical responses to positive end-expiratory pressure in patients with airway obstruction during controlled ventilation

OBJECTIVE: To reevaluate the clinical impact of external positive end-expiratory pressure (external-PEEP) application in patients with severe airway obstruction during controlled mechanical ventilation. The controversial occurrence of a paradoxic lung deflation promoted by PEEP was scrutinized. DESIGN: External-PEEP was applied stepwise (2 cm H(2)O, 5-min steps) from zero-PEEP to 150% of intrinsic-PEEP in patients already submitted to ventilatory settings minimizing overinflation. Two commonly used frequencies during permissive hypercapnia (6 and 9/min), combined with two different tidal volumes (VT: 6 and 9 mL/kg), were tested. SETTING: A hospital intensive care unit. PATIENTS: Eight patients were enrolled after confirmation of an obstructive lung disease (inspiratory resistance, >20 cm H(2)O/L per sec) and the presence of intrinsic-PEEP (> or =5 cm H(2)O) despite the use of very low minute ventilation. INTERVENTIONS: All patients were continuously monitored for intra-arterial blood gas values, cardiac output, lung mechanics, and lung volume with plethysmography. MEASUREMENTS AND MAIN RESULTS: Three different responses to external-PEEP were observed, which were independent of ventilatory settings. In the biphasic response, isovolume-expiratory flows and lung volumes remained constant during progressive PEEP steps until a threshold, beyond which overinflation ensued. In the classic overinflation response, any increment of external-PEEP caused a decrease in isovolume-expiratory flows, with evident overinflation. In the paradoxic response, a drop in functional residual capacity during external-PEEP application (when compared to zero-external-PEEP) was commonly accompanied by decreased plateau pressures and total-PEEP, with increased isovolume-expiratory flows. The paradoxic response was observed in five of the eight patients (three with asthma and two with chronic obstructive pulmonary disease) during at least one ventilator pattern. CONCLUSIONS: External-PEEP application may relieve overinflation in selected patients with airway obstruction during controlled mechanical ventilation. No a priori information about disease, mechanics, or ventilatory settings was predictive of the response. An empirical PEEP trial investigating plateau pressure response in these patients appears to be a reasonable strategy with minimal side effects.     

In vitro leishmanicidal activity of Tityus discrepans scorpion venom

Leishmania parasites are sensitive to peptides with antimicrobial and ion-channel inhibitory activity. Because scorpion venoms are rich sources of such peptides, the leishmanicidal effect of Tityus discrepans venom was investigated. A negative correlation between cell growth and venom concentration was observed for venom-treated cultures of Leishmania (L.) mexicana mexicana promastigotes; 50% growth inhibition was obtained at 0.4 μg/ml. Light microscopy showed rounded, highly vacuolated L. (L.) m. mexicana cells with impaired flagellar motion after 15 min of incubation at 35 μg/ml. Ultrastructural studies confirmed an intense cytoplasm vacuolation and also enlargement of the flagellar pocket. Survival rates for New World Leishmania promastigotes (75% venom effective concentration, μg/ml) obtained after acute (1 h) venom toxicity tests were: L. (L.) m. mexicana (2.3), Leishmania (V.) braziliensis (11.3), and Leishmania (L.) chagasi (56.2). Heat (90°C) treatment of venom and fraction TdII abolished most of their leishmanicidal effect. Acute toxicity assays performed with Sephadex G-50 fractions indicated that leishmanicidal activity is associated with the venom lowest molecular mass components (2.8–7.4 kDa), as determined by MALDI-TOF mass spectrometry.     

Differences in virulence factors among clinical isolates of Escherichia coli causing cystitis and pyelonephritis in women and prostatitis in men

Differences in the presence of nine urovirulence factors among clinical isolates of Escherichia coli causing cystitis and pyelonephritis in women and prostatitis in men have been studied. Hemolysin and necrotizing factor type 1 occur significantly more frequently among isolates causing prostatitis than among those causing cystitis (P < 0.0001) or pyelonephritis (P < 0.005). Moreover, the papGIII gene occurred more frequently in E. coli isolates associated with prostatitis (27%) than in those associated with pyelonephritis (9%) (P < 0.05). Genes encoding aerobactin and PapC occurred significantly less frequently in isolates causing cystitis than in those causing prostatitis (P < 0.01 and P < 0.0001, respectively) and pyelonephritis (P < 0.01 and P < 0.0001, respectively). No differences in the presence of Sat or type 1 fimbriae were found. Finally, AAFII and Bfp fimbriae are no longer considered uropathogenic virulence factors since they were not found in any of the strains analyzed. Overall, the results showed that clinical isolates producing prostatitis need greater virulence than isolates producing pyelonephritis in women or, in particular, cystitis in women (P < 0.05). Overall, the results suggest that clinical isolates producing prostatitis are more virulent that those producing pyelonephritis or cystitis in women.     

High prevalence of diabetes and impaired fasting glucose in urban Latin America: the CARMELA Study

Aims Cardiovascular risk is increased with glucose metabolism abnormalities. Prevalence data can support public health initiatives required to address this risk. The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study was designed to estimate the prevalence of Type 2 diabetes, impaired fasting glucose and related risk factors in seven urban Latin American populations. Methods CARMELA was a cross‐sectional, population‐based study of 11 550 adults 25–64 years of age. With a multi‐stage sample design of a probabilistic nature, approximately 1600 subjects were randomly selected in each city. Results Overall, the prevalence of diabetes was 7.0% (95% confidence intervals 6.5–7.6%). The prevalence of individuals with diabetes or impaired fasting glucose increased with increasing age. In the oldest age category, 55–64 years of age, prevalence of diabetes ranged from 9 to 22% and prevalence of impaired fasting glucose ranged from 3 to 6%. Only 16.3% of people with prior diagnosis of diabetes and who were receiving pharmacologic treatment, were in good glycaemic control (fasting glucose < 6.1 mmol/l). The prevalence of diabetes in individuals with abdominal obesity was approximately twofold higher. Participants with hypertension, elevated serum triglycerides and increased common carotid artery intima‐media thickness were also more likely to have diabetes. Conclusions The prevalence of diabetes and impaired fasting glucose is high in seven major Latin American cities; intervention is needed to avoid substantial medical and socio‐economic consequences. CARMELA supports the associations of abdominal obesity, hypertension, elevated serum triglycerides and carotid intima‐media thickness with diabetes.     

A survey of different high resolution visualization modes of a volumetric object with applications

Summary In view of the variety of 3D representation techniques, a clinical study was carried out in order to evaluate their respective usefulness. It appears that a single technique cannot be claimed to be valid for all clinical situations and that a combination of representations brings more relevant information. Among the different techniques a clear delineation must be established between those which allow the accurate definition of landmarks (multiplanar reformation, surface representation), and those which do not (integral shading, reconstructed radiology). The main point is the possibility to recognize anatomical landmarks on these latter modes and to choose oblique cut planes in relation to them. Visualization quality is strongly dependent upon the acquisition protocol which must provide a spatial resolution as isotropic as possible.

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Une revue de différents modes de visualisation en haute résolution d'un objet volumique avec des applications

Résumé Face à la variété des techniques de représentation 3D une étude clinique a été conduite pour évaluer leurs utilités respectives. Il apparait qu'une technique unique ne peut pas convenir à toutes les situations cliniques et qu'une combinaison de différents modes de présentation apporte une information plus pertinente. Parmi les différentes techniques une distinction claire doit être établie entre celles qui autorisent la prise de repères précis (reformatage multiplanaire, représentation de surface), et celles qui ne le permettent pas (ombrage intégral, radiologie reconstruite). Le point principal est la possibilité de reconnaître des repères anatomiques sur ces derniers modes et de choisir des plans de coupe en relation avec eux. La qualité de la visualisation dépend étroitement du protocole d'acquisition qui doit fournir une résolution aussi isotrope que possible.

     

Comparison of the prognostic value of Chronic Liver Failure Consortium scores and traditional models for predicting mortality in patients with cirrhosis

Background and aim

Recently, the European Association for the Study of the Liver – Chronic Liver Failure (CLIF) Consortium defined two new prognostic scores, according to the presence or absence of acute-on-chronic liver failure (ACLF): the CLIF Consortium ACLF score (CLIF-C ACLFs) and the CLIF-C Acute Decompensation score (CLIF-C ADs). We sought to compare their accuracy in predicting 30- and 90-day mortality with some of the existing models: Child-Turcotte-Pugh (CTP), Model for End-Stage Liver Disease (MELD), MELD-Na, integrated MELD (iMELD), MELD to serum sodium ratio index (MESO), Refit MELD and Refit MELD-Na.

Long-Term Immune Recovery After Hematopoietic Stem Cell Transplantation for ADA Deficiency: a Single-Center Experience

Journal of Clinical Immunology - Unconditioned hematopoietic stem cell transplantation (HSCT) is the recommended treatment for patients with adenosine deaminase (ADA)-deficient severe combined...     

Mutation analysis of the SDHD gene in four kindreds with familial paraganglioma: description of one novel germline mutation.

The familial paraganglioma syndrome is an autosomal dominant disorder characterized by the presence of carotid body paragangliomas and, less frequently, paragangliomas of the glomus jugulare, glomus vagale, and adrenal pheochromocytomas. Germline mutations of the genes for succinate dehydrogenase subunits D, B, or C (SDHD, SDHB, SDHC) have been identified in some kindreds with familial paraganglioma. In this study, we report the clinicopathologic features of four different kindreds with familial paraganglioma, which were screened for germline mutations in the SDHD gene. DNA was obtained from tumor and normal tissue, as well as from peripheral blood. Mutation analysis was performed by single-strand conformation polymorphism analysis and DNA sequencing. SDHD germline mutations were detected in the affected family members of the four families, as well as in several asymptomatic carriers. An identical mutation in exon 4 of SDHD (334-337delACTG) was identified in two apparently unrelated kindreds. The third family showed a germline mutation in exon 2 (W43X). The mutations present in these three families had been previously described in Spanish families, suggesting a founder effect. The fourth family exhibited a mutation in exon 2 of SDHD (170-171delTT), which had not been previously identified. The affected family members of the four kindreds showed paragangliomas, located in the head and neck region, and all of them were benign. These results confirm that genetic testing of SDHD may be a powerful tool for the identification of the syndrome in patients with multiple or bilateral paragangliomas.     

Association of adrenal medullar and cortical nodular hyperplasia: a report of two cases with clinical and morpho-functional considerations

Arterial hypertension of adrenal etiology is mainly attributed to primary hyperaldosteronism. However, subtle expressions of hyperadrenergic or glucocorticoid excess can also generate arterial hypertension. The present report describes two hypertensive patients cataloged as resistant essential hypertensives, in whom adrenal masses were found incidentally, who highlight the need to recognize these tenuous clinical or laboratory presentations. Case 1 was a 50-yr-old female with hyperadrenergic hypertension associated to a left adrenal node, normal cortisol and aldosterone:renin ratio, marginally increased urinary normetanephrine, and a positive 131I MIBG radioisotope scan. Adrenalectomy normalized blood pressure and urinary metanephrines. Pathology showed a hyperplastic adrenal medulla associated to a multinodular cortical hyperplasia. Case 2 was a 62- yr-old female with progressive hypertension, a slight Cushing phenotype, non-suppressible hypercortisolism, normal urinary metanephrines, and bilateral adrenal nodes. Bilateral adrenalectomy and subsequent replacement normalized blood pressure and phenotypic stigmata. Pathology demonstrated bilateral cortical multinodular hyperplasia and medullary hyperplasia. The clinical study in both patients was negative for MEN. The apparently rare association of cortical and medullary lesions presented by both patients is probably overlooked in routine pathology exams, but should be meticulously searched since the crosstalk between the adrenal cortex and medulla may prompt dual abnormalities.