胎儿和新生儿同种异体免疫性血小板减少症:进展与持续性争议

胎儿和新生儿同种异体免疫性血小板减少症(AIT)是引起胎儿和新生儿严重血小板减少的最常见原因.母亲针对源自父亲的胎儿血小板抗原的IgG抗体,在妊娠早期就可通过胎盘,通常导致胎儿严重血小板减少.由于一些血小板减少症临界值(50、100或150×109/L)的不同,他们的发生率亦各不相同.但在多数未经选择的人群中,AIT影响1/1 000到1/2 000活产数.在新生儿病房,临床确诊的重症AIT很罕见,可能只有1:10 000分娩数.     

Comparison of C(18)-carboxypropylbetaine and standard N-acetyl-L-cysteine-NaOH processing of respiratory specimens for increasing tuberculosis smear sensitivity in Brazil

Techniques to improve the sensitivity of smear microscopy would facilitate early tuberculosis (TB) diagnosis and disease control, especially in low-income countries where the positive predictive value is high. C(18)-carboxypropylbetaine (CB-18) is a zwitterionic detergent that helps to compensate for the innate buoyancy of mycobacteria, potentially enhancing recovery by centrifugation. Previous data suggest that CB-18 may increase the sensitivity of smear, culture, and molecular amplification diagnostic testing. The goal of the present study was to evaluate if the sensitivity of the smear technique using light microscopy could be improved by treating respiratory samples with CB-18. In the first phase, respiratory specimens were collected consecutively from patients with suspected pulmonary tuberculosis in a tertiary-care hospital in Rio de Janeiro, Brazil (236 specimens were analyzed). After protocol modifications, another 120 respiratory specimens were evaluated. The standard technique was N-acetyl-L-cysteine with sodium hydroxide (NALC-NaOH) treatment, smear concentration with centrifugation, and Ziehl-Neelsen staining. Culture on L?wenstein-Jensen slants was performed on all specimens for use as the "gold standard." No specimens from patients undergoing active TB treatment were included. The initial protocol for CB-18 processing resulted in a sensitivity of 59.6% and specificity of 96.8% compared to standard processing with a sensitivity of 66.0% and specificity of 96.8%. Using the modified protocol, the sensitivity of CB-18 increased to 71.4% with a specificity of 97.0% versus standard processing with a sensitivity of 61.9% and a specificity of 99.0%. The diagnostic yield of acid-fast bacillus smear with CB-18 in the absence of fluorescence microscopy and PCR compared to standard processing with NALC-NaOH was not significantly different, although the power to detect a difference by the modified assay was low.     

Effect of Brazilian copaiba oils on Leishmania amazonensis

Ethnopharmacological relevance

Copaiba oil has been used in folk medicine since the 19th century. The use of copaiba oils to treat leishmaniasis is cited in several ethnopharmacological studies. Nevertheless, the potential antileishmania of copaiba oils had not been studied.

Aim of the study

Eight different kinds of Brazilian copaiba oils were screened for antileishmanial activity.

Materials and methods

The antiproliferative effect of copaiba oil on promastigote and amastigote axenic were determined. To determine the survival index peritoneal macrophage were infected with promastigotes of Leishmania amazonensis and treated with copaiba oil. The cytotoxic effect of copaiba oil was assessed on macrophage strain J774G8 by assay of sulforhodamine B.

Results

Copaiba oils showed variable levels of activity against promastigote forms with IC₅₀ values in the range between 5 and 22 μg/mL. The most active oil was that from Copaifera reticulata (collected in Pará State, Brazil) with IC₅₀ values of 5, 15, and 20 μg/mL for promastigote, axenic amastigote and intracellular amastigote forms, respectively. Amphotericin B showed IC₅₀ of 0.058 and 0.231 μg/mL against promastigote and amastigote forms, respectively. Cytotoxicity assay showed that this copaiba oil obtained from Copaifera reticulata showed low cytotoxicity against J774G8 macrophages.

Conclusion

Copaiba oils showed significant activity against the parasite Leishmania amazonensis.     

In vitro antifungal activity of extracts and neolignans from Piper regnellii against dermatophytes

The present study was designated to evaluate the in vitro antidermatophyte activity of extracts from leaves of Piper regnellii as well as of the bioactivity-directed isolation of neolignans. The antifungal assay was performed by microdilution techniques. The hydroalcoholic extract of Piper regnellii leaves presented a strong activity against the dermatophyte fungi Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Microsporum gypseum with MICs of 15.62, 15.62, 15.62 and 62.5 microg/ml, respectively. On light microscopy and scanning electron microscopy of nail fragments not exposed to hydroalcoholic extract of Piper regnelli leaves, well-formed and extensive mycelial growth was seen. On nail fragments exposed to hydroalcoholic extract at concentrations more than 1.2mg/ml and then inoculated with spore suspension, growth was not seen. The hydroalcoholic extract was fractionated on silica gel in to nine fractions. The active chloroform fraction was lyophilized and chromatographed by column chromatography on silica gel. Structures were established by comparison with literature data and identified as eupomatenoid-3 and eupomatenoid-5. The pure compounds showed strong activity on Trichophyton rubrum with MIC of 50 and 6.2 microg/ml, respectively. Comparing the activity of the active chloroform fraction obtained from hydroalcoholic crude extract with that of isolated compound eupomatenoid-5, it is clear that this showed the same results against Trichophyton rubrum. The results showed that the plant could be explored for possible antifungal agents and provides preliminary scientific validation for the traditional medicinal use of this plant.     

双波长薄层扫描法测定痛得安胶囊中新乌头碱的含量

目的：建立痛得安胶囊中新乌头碱的含量测定方法。方法：采用双波长薄层扫描法,以正己烷－乙酸乙酯－无水乙醇－氨水（１２：８：２．５：０．５）为展开剂,碘化饿钾试液为显色剂,测定该制剂中新乌头碱的含量。结果：线性范围为１～６ｕｇ。平均回收率为９４．８０％,ＲＳＤ为２．０３％。结论：本法操作简便。结果可靠。实用,适合该制剂中新乌头碱的含量测定。     

Redox imbalance influence in the myocardial Akt activation in aged rats treated with DHEA

This study examined, in young and old (3 and 24 month-old, respectively) healthy Wistar rats, the in vivo effect of DHEA (10 mg/kg body weight) administered subcutaneously for 5 weeks. Reduced (GSH) and oxidized (GSSG) glutathione levels, glucose — 6-phosphate dehydrogenase (G6PDH), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and thioredoxin (Trx) reductase activities, hydrogen peroxide steady-state concentration and Nrf2, GST, Trx-1, Akt and p-Akt expressions were assessed in heart tissue. DHEA treatment significantly increased GST activity in 3 and 24 month-old treated groups. The aging factor diminished hydrogen peroxide concentration and Nrf2 expression, independently of treatment. However, the aging process increased GST, Akt and p-Akt expressions in both 24 month-old groups. The aged group responded differently to DHEA respective to GSSG content, GPx activity and p-Akt concentration. Further studies are needed to form conclusions about the efficacy and safety of DHEA replacement in the elderly, and to better understand DHEA's net effect on oxidative stress parameters and its modulation of signaling cascades.     

Prediction of significant liver fibrosis in kidney transplant patients with chronic hepatitis C virus infection: the TX‐3 index

Summary. HCV infection is highly prevalent among kidney transplant (KT) recipients. The natural history and management of these patients are controversial. We sought to assess the diagnostic value of noninvasive markers of liver fibrosis in KT HCV‐infected patients. This cross‐sectional study included 102 KT individuals with positive HCV‐RNA. Bivariate and multivariate analyses were used to identify variables associated with significant fibrosis (METAVIR ≥ F2). Significant fibrosis was observed in 20 patients (20%). Time after transplantation, AST level, and platelet count were identified as independent predictors of significant fibrosis. Based on the regression model, a simplified index was devised. The AUROC for the TX‐3 model was 0.867 ± 0.081 (0.909, when adjusted by DANA). Values ≤4.0 of TX‐3 showed a NPV of 97% and scores >9.6 exhibited a PPV of 71%. If biopsy indication was restricted to scores in the intermediate range of TX‐3, this could have been correctly avoided in 68% of cases. The APRI score provided a correct diagnosis in only 47 individuals (46%) and exhibited lower diagnostic indices for both cutoffs, as compared to the TX‐3 index. Comparison of AUROCs showed a trend towards superior diagnostic accuracy for TX‐3 over APRI, although the difference between AUROCs did not reach statistical significance (0.867 ± 0.053 vs 0.762 ± 0.066, respectively, P = 0.064). In conclusion, significant liver fibrosis can be reliably predicted in KT HCV‐infected subjects by simple and widely available parameters. If additional studies confirm our results, this model might obviate the requirement for a liver biopsy in a significant proportion of those patients.