Transepithelial paracellular leakiness induced by chronic phorbol ester exposure correlates with polyp-like foci and redistribution of protein kinase C-alpha

Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA) causes a near immediate and total decrease of transepithelial electrical resistance (TER), continuation of exposure for 3 to 4 days results in a tachyphylactic response as TER begins to return to control levels. Recovery of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control level. A reciprocal change in the transepithelial flux of D-mannitol indicates that the TER decrease is indicative of an increase in tight junction permeability. Exposure of cell sheets to TPA for several days also results in the appearance of multilayered polyp- like foci (PLFs) across the otherwise one cell layer thick cell sheets. The pattern of penetration of the electron dense dye, ruthenium red, from the apical surface, across the tight junction and into the lateral intercellular space indicates that the tight junctions of the cell sheet become uniformly leaky after acute exposure to TPA. However, when exposure is continued for several days, only the junctions of cells in the PLFs manifest leakiness. The decrease in TER following acute TPA exposure correlates with the translocation of protein kinase C-alpha (PKC alpha) into a membrane-associated compartment. With exposure of several days, only a trace of PKC alpha is visible by Western immunoblot, and this is in the membrane-associated compartment. Immunofluorescent microscopy indicates that the trace of PKC alpha seen in the Western immunoblots is ascribable distinctly to cells of the PLFs. Monolayer areas between PLFs show no discernible immunofluorescent signal. The data therefore indicate that tight junction barrier function may be restored in certain areas by the down regulation of PKC alpha from the membrane-associated compartment. Failure to down regulate may result in the paracellular leakiness and abnormal cell architecture of the PLFs. Possible implications of this model for in vivo epithelial tumor promotion are discussed.      

Sputum tumour necrosis factor-alpha and leukotriene concentrations in cystic fibrosis

It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.     

A new amino acid mixture permits new approaches to the treatment of phenylketonuria

A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.     

Rapunzel syndrome with a fatal outcome in a neglected child

The “Rapunzel” syndrome (a trichobezoar with a long tail extending from the stomach to the small bowel) is an uncommon disease. It is related to severe complications but rarely associates to a fatal outcome. We report a case of a 5-year-old girl admitted at the emergency department in cardiorespiratory arrest whose autopsy disclosed an ileal perforation that is caused by a long bezoar extending from the stomach to the small bowel. The authors discuss a possible link between Rapunzel syndrome and child neglect.     

Hormonal cryptorchidism therapy: systematic review with metanalysis of randomized clinical trials

The importance of cryptorchidism treatment concerns the possibility of diminishing risk of malignant degeneration and improving fertility. Success rates of hormonal treatment vary: 0–55% with human chorionic gonadotropin (hCG) and 9–78% with gonadotropin-releasing hormone (GnRH). Due to uncertainties regarding the effectiveness of this treatment, a systematic review and meta-analysis of randomized controlled trials (RCTs) on hormonal cryptorchidism treatment was done using the methodology of Cochrane Collaboration. Two studies compared hCG with GnRH, with a testicular descent rate of 25% vs. 18%, respectively. Nine trials compared intranasal LHRH with placebo, with complete testicular descent rates of 19% vs. 5%. Two other studies comparing doses and administration intervals could not be pooled together due to heterogeneity. With the information analyzed until the present, the evidence for the use of hCG vs. GnRH shows advantages for hCG, and this review also shows that there is evidence that luteinizing hormone releasing hormone (LHRH) is more effective than placebo. But because this evidence is based on few trials, with small sample sizes and moderated risk of bias, this treatment cannot be recommended for everyone, and there is no evidence that supports hCGs use in larger doses and larger intervals. Results from this systematic review are important for developing better RCTs that may decrease the uncertainty of cryptorchidism treatment.     

A multicenter,randomized, double blind placebo-controlled trial of amoxicillin/clavulanate for the prophylaxis of fever and infection in neutropenic children with cancer

AIM OF THE STUDY: To evaluate the effectiveness of oral amoxicillin/clavulanate (25 mg/kg every 12 h) for prevention of fever and/or infection in neutropenic children with cancer. METHODS: Multicenter, prospective, randomized, double blind placebo-controlled trial. RESULTS: In the intention-to-treat analysis, amoxicillin/clavulanate had a 12% benefit increase in terms of reduction in the incidence of febrile or infectious episodes, compared with placebo [44 of 83 (53%) vs.55 of 84 (65%); 95% confidence interval, -28% to +3%; P = 0.101]. This benefit was also associated with a 30% increase in the probability of failure-free survival at Day 15 (P = 0.138). A logistic regression analysis showed the effect of prophylaxis to be relevant, especially in patients with leukemia or lymphoma and in those not receiving hematopoietic growth factors, with 17 and 15% absolute benefit increases (logistic P = 0.014 and 0.034, respectively). Compliance with oral drugs was good, with very few and nonsevere drug-related adverse events. CONCLUSIONS: In this study amoxicillin/clavulanate was associated with a detectable clinical effect in the reduction of fever and infection in neutropenic children with cancer, especially those with acute leukemia and not receiving growth factors; the study was not powered to demonstrate a statistically significant effect in the overall patient population.     

Effects of deferiprone on immune status and cytokine pattern in thalassaemia major

OBJECTIVE: The present study was undertaken to evaluate the possible occurrence of immunological abnormalities in thalassaemia major patients treated with deferiprone (L1). METHODS: Longitudinal observational cohort study. RESULTS: The absolute number of CD8+ lymphocytes was high and the CD4/CD8 ratio low before L1 treatment; these parameters returned to normal after 3 months of L1 treatment. TNF-alpha, IL-2 and IL-2sRalpha were elevated before L1 treatment (11.83 +/- 1.75, 11.75 +/- 3.91, 1,409 +/- 621 pg/ml, respectively), while IL-6 was normal (2.58 +/- 0.79 pg/ml). After 12 months of treatment, IL-10 was higher than in previous periods, although always within the normal range. TNF-alpha, IL-2 and IL-2sRalpha returned to normal after 12, 6, and 3 months of L1 treatment, respectively.