A Subset of Type I Conventional Dendritic Cells Controls Cutaneous Bacterial Infections through VEGFα-Mediated Recruitment of Neutrophils

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Neonatal RBC transfusions: Do benefits outweigh risks?

Preterm neonates represent one of the most transfused categories of patients. Their target hematocrits, however, are mainly based on expert opinion. The risk of transfusions are very high in the smallest preterm baby with a weak immune response, immature antioxidant ability, fragile germinal matrix and impaired cerebral autoregulation, yet red cell transfusions remain the only life saving measure in the baby with symptomatic anemia.Minimizing phlebotomy losses, following a restrictive transfusion policy and using screened, leukocyte depleted, irradiated, single donor blood remain the best means of avoiding the possible risks while maximizing the benefits of red cell transfusions in the preterm newborn.     

Thiosemicarbazide functionalized carbon quantum dots as a fluorescent probe for the determination of some oxicams: application to dosage forms and biological fluids

In this study, highly fluorescent water-soluble nitrogen and sulfur doped carbon quantum dots (N, S-CQDs) were synthesized via a one-step hydrothermal process utilizing citric acid as a carbon source and thiosemicarbazide as a sulfur and nitrogen source. The obtained N, S-CQDs exhibited an intense emission band at 415 nm (λ_ex = 345 nm). In the presence of either piroxicam, tenoxicam or lornoxicam, the emission band at 415 nm was significantly quenched which might be triggered due to destruction of the surface passivation layer of the N, S-CQDs. A linear correlation was found between the reduction in the fluorescence intensity of N, S-CQDs and the concentration of each drug in the ranges of 2.0–25.0 μM, 10.0–100.0 μM and 20.0–200.0 μM with correlation coefficients of more than 0.999 for all drugs. The detection limits were 0.49 μM, 1.58 μM and 4.63 μM for piroxicam, tenoxicam and lornoxicam, respectively. The effect of experimental parameters affecting the performance of the method was investigated and optimized. The developed sensor has the advantages of simplicity, time-saving, convenience and satisfactory selectivity for determination of the studied drugs in dosage forms with high % recoveries (98.86–101.69%). The method was extended for determination of piroxicam in spiked plasma with % recoveries ranging from 97.95–101.36%. The method was validated in accordance with International Council of Harmonization (ICH) standards, and the results obtained were compared statistically to those given by reported methods, indicating no significant differences in the level of accuracy and precision. The mechanism of the quenching process was studied and elucidated. The structure–activity relationship between the three drugs and the quenching efficiency was also studied and discussed.

Highly fluorescent nitrogen and sulfur doped carbon quantum dots were synthesized via hydrothermal process using citric acid and thiosemicarbazide. The dots had an emission band at 415 nm (λ_ex = 345 nm). The polarity of the studied drugs affects the method’s sensitivity.     

Adipocyte-fatty acid binding protein induces apoptosis in DU145 prostate cancer cells

Adipocyte-fatty acid binding protein (A-FABP) is a 14-15 kDa cytoplasmic protein that binds unesterified fatty acids (FA). It is believed that A-FABP is present in normal cells and disappears in cancer cells. Prostate cancer DU145 cells lack expression of A-FABP. Here, we report that transfection of A-FABP blocked growth of DU145 cells suggesting its role as a tumor suppressor. A-FABP transfected- prostate cancer DU145 cells underwent apoptosis when induced to overexpress A-FABP using an ecdysone-controlled expression system. DU145 cell cultures in complete medium exhibited a maximum of approximately 28% of apoptotic cells after 96 h of exposure to an ecdysone analog, Ponasterone A. We found that the possible mechanisms leading to the observed apoptotic effect may be due, in part, to an overexpression of tumor necrosis factor-alpha (TNF-alpha) and a moderate downregulation of transforming growth factor-alpha (TGF-alpha) in DU145 cells overexpressing A-FABP. The epidermal growth factor receptor (EGFR)/phosphatidyl inositol 3-kinase (PI 3-kinase) signaling pathway was not altered in these cells, suggesting that A-FABP may cause apoptosis by inducing downregulation of essential autocrine growth factors and/or upregulation of pro-apoptotic ones.     

Tumor necrosis factor-α production from mononuclear cells in nephrotic syndrome

Tumor necrosis factor-alpha (TNF-alpha) levels in supernatant fluid from cultured peripheral blood mononuclear cells (PBMC) were measured by ELISA in 54 children with active non-inherited forms of primary nephrotic syndrome (PNS), 10 nephrotics in remission, and 10 healthy controls. Children with active PNS included 21 patients with steroid-sensitive (SS) minimal change nephrotic syndrome (MCNS), 5 patients with steroid-resistant (SR) MCNS, 11 with SR focal segmental glomerulosclerosis (FSGS), 6 patients with SS diffuse mesangial proliferation (DMP), 5 patients with SR DMP, and 6 patients with mesangiocapillary glomerulonephritis (MCGN). Patients with active PNS had elevated TNF-alpha production compared with controls. Remission was associated with normalization of TNF-alpha production. There was a positive correlation between TNF-alpha production and the degree of proteinuria ( r=0.34, P=0.013), mesangial hypercellularity ( r=0.42, P=0.028), and glomerulosclerosis ( r=0.46, P=0.001). By using ROC curve, TNF-alpha production greater or equal to a cut-off point of 50 pg/ml could be used to predict resistance to steroid therapy (predictability 93.2%). By discriminate analysis, TNF-alpha production could be used to discriminate between patients with SR MCNS, SR FSGS, and SR DMP (predictability 100%). In conclusion, TNF-alpha from cultured PBMC might be involved in the pathogenesis of proteinuria as well as the pathological changes that occur in non-inherited forms of PNS. TNF-alpha levels in PBMC culture could be used to predict the pathological type of PNS and the response of these patients to steroid therapy.     

Spectrophotometric determination of binary mixtures of pseudoephedrine with some histamine H1-receptor antagonists using derivative ratio spectrum method

A derivative spectrophotometric method is developed for the assay of three binary mixtures of pseudoephedrine with fexofenadine (mix I), cetirizine (mix II) and loratadine (mix III). The method is based on the use of the first derivative of the ratio spectrum. The ratio spectrum was obtained by dividing the absorption spectrum of the mixture by that of one of the components. The concentration of the other component was determined from its respective calibration graph treated similarly. Moreover, the influence of Deltalambda for obtaining the first derivative of the ratio spectra and the effect of the divisor concentration on the calibration graphs were studied. The described method was applied for the determination of these combinations in synthetic mixtures and dosage forms. The results obtained were accurate and precise.     

The effect of bread making steps on the degradation of aflatoxins produced as a result of single inoculation with Aspergillus flavus and combined inoculation with Aspergillus flavus and Aspergillus ochraceus

This study aimed to determine the effect of bread making steps on the stability of aflatoxin. Sakha 8 wheat and Gemaiza 5 wheat cultivars, were used in the present study. They were inoculated with a dense spore suspension of toxigenic fungal species of Aspergillus flavus and a non toxigenic species of Aspergillus ochraceus singly and combined. Aflatoxin concentration was determined in the whole wheat grain, after milling, after fermentation, and after bread-baking process. Results showed that the highest reduction percentage for the total aflatoxins (81, G1 and G2), was in Sakha 8 (32.96%) (single treatment), Gemaiza 5 (19.54%) (single treatment ), Gemaiza 5 (18.65%) (combined treatment), and finally in Sakha 8 (16.49%) (combined treatment). There was no significant difference (p < 0.05) in aflatoxins content between Sakha 8 and Gemaiza 5 treated singly and in a combined way before and after milling process. In the mean time, the percentage of AFB1, AFG1 and AFG2 were reduced by 31.98%, 44.53% and 35.35%, respectively, while the total aflatoxins concentration were reduced by 41.17% after baking. Results also showed the presence of a significant difference at p < 0.05 among the whole grain, after milling and after baking concerning AFG1, AFG2 and the total aflatoxins content. No significant difference was found in case of AFB1.