Clinical and epidemiologic characteristics of respiratory syncytial virus subgroups A and B infections in Santa Fe, Argentina

Respiratory Syncytial Virus (RSV) has two major antigenic groups, A and B. The implications of these variants in the epidemiology and pathogenesis of RSV infection are not well defined. This study was undertaken to compare the two RSV subgroups in patients admitted to hospital. Clinical and epidemiologic features of RSV subgroups in children under 30 months of age with proven RSV acute lower respiratory infections were examined during 4 winters from 1993 to 1996 in Santa Fe, Argentina. RSV typing was carried out with monoclonal antibodies in nasopharyngeal cells by indirect immunofluorescence. Of the 177 RSV positive nasopharyngeal aspirates obtained from 1993 to 1996, 85 (48%) were available for typing. Seventy-three (85.9%) specimens were identified as Subgroup A and 12 (14.1%) as Subgroup B. Except in 1993, in which only Subgroup A was detected, both variants circulated throughout the epidemic season. Subgroup A infections produced more severe disease than Subgroup B infections, as assessed by the length of the hospital stay and the use of respiratory support. This difference was age related, being evident in infants 0-6 months old. Patients with Subgroup B infections were also significantly less frequently breast-fed (95% vs. 75% for A and B subgroups, respectively; P = 0.04). It is concluded that the severity of disease in Argentinian patients admitted with acute RSV infections may be associated with Subgroup A strains as determined by a serogrouping method.     

Short communication: high effectiveness of etravirine in routine clinical practice in treatment-experienced HIV type 1-infected patients

The effectiveness of etravirine has not been thoroughly investigated in routine clinical practice, where adherence rates and the heterogeneous nature of patients differ from the clinical trial setting. We evaluated the effectiveness of rescue regimens containing etravirine and the factors associated with treatment response. Multicenter retrospective cohort of all consecutive patients was recruited in a routine clinical practice setting. Patients were taking rescue regimens containing etravirine plus an optimized background regimen. The primary endpoint was the percentage of patients with HIV-1 RNA <50 copies/ml at week 48. The secondary endpoints were those factors associated with treatment response to etravirine. Endpoints were evaluated using univariate and multivariate analysis. A total of 122 patients were included with a median viral load of 11,938 (1055-55,500) copies/ml at baseline. The most frequent drugs in the backbone were darunavir/ritonavir in 98 (80.3%) patients and raltegravir in 76 (62.3%). In the full dataset analysis, 73% (89/122; 95% CI, 64-81%) of patients responded to treatment at week 48; in the on-treatment analysis, 82% (89/109; 95% CI, 71-87%) responded. The factors associated with treatment failure to etravirine [HR (95% CI)] were baseline CD4(+) T cell count <200 cells/mm(3) [2.45 (1.17-5.16)] and use of raltegravir [0.47 (0.22-0.99)] and darunavir [0.45 (0.21-0.98)] as backbone drugs. Skin rash was the only adverse event directly related to etravirine and led to withdrawal in three patients (2.5%). In routine clinical practice, rescue ETR-containing regimens are well tolerated and achieve rates of virological suppression higher than those observed in its pivotal clinical trials, especially when combined with darunavir and raltegravir.     

Combination of intracortically administered VEGF and environmental enrichment enhances brain protection in developing rats

Postnatal development of the visual cortex is modulated by experience, especially during the critical period. In rats, a stable neuronal population is only acquired after this relatively prolonged period. Vascular endothelial growth factor (VEGF) is the most important angiogenic factor and also has strong neuroprotective, neurotrophic and neurogenic properties. Similar effects have been described for rearing in enriched environments. Our aim is to investigate the vascular and neuronal effects of combining VEGF infusion and environmental enrichment on the visual cortex during the initial days of the critical period. Results showed that a small percentage of Cleaved Caspase-3 positive cells colocalized with neuronal markers. The lesion produced by the cannula implantation resulted in decreased vascular, neuronal and Caspase-3 positive cell densities. Rearing under enriched environment was unable to reverse these effects in any group, whereas VEGF infusion alone partially corrected those effects. A higher effectiveness was reached by combining both the procedures, the most effective combination being when enriched-environment rearing was introduced only after minipump implantation. In addition to the angiogenic effect of VEGF, applied strategies also had synergic neuroprotective effects, and the combination of the two strategies had more remarkable effects than those achieved by each strategy applied individually.     

Overall breast density in MR mammography: diagnostic and therapeutic implications in breast cancer

The objective of this study was to assess the efficacy of MR mammography (MRM) in evaluating breast cancer extent in women with fatty or dense breasts, and its contribution to the therapeutic approach. The authors reviewed 97 carcinomas detected in 93 women (both symptomatic and from screening) that were classified in two groups according to breast density pattern. Mammography, ultrasound (US), and MRM were performed to evaluate size, extension of the in situ component, presence of multifocal/multicentric disease, and contralateral involvement. Results obtained on mammography plus US were balanced against MRM, considering pathologic analysis as the gold standard. For fatty breasts (n=47), exact measurement was found on mammography plus US and on MRM alone in 70%, underestimation on mammography plus US 23.5% and on MRM 11% (P=0.005). For dense breasts (n=50), exact measurement was found on mammography plus US in 40% and on MRM alone 68%, underestimation on mammography plus US 52% and on MRM 10% (P=0.005). Overall, good correlation (R>0.71) was found between pathologic and clinical size with all imaging methods; nevertheless, when evaluating multifocal/multicentric disease, a poor correlation was observed between histologic assessment and mammography plus US (R=0.52), but it was excellent with regard to MRM (R=0.99). In fatty breasts, the combination of mammography and US allows for a precise assessment of tumoral extension. However, these results show that in dense breasts, MRM is superior to mammography plus US, suggesting that its systematic use in this group of patients is justifiable.     

Role of cervical cerclage and prolonged antibiotic therapy with azithromycin in patients with previous perinatal loss amnionitis

In the group of 35 patients with cerclage, intermediate fetal mortality was reduced from 37.1% to 0 (p?p?=?0.606); prematurity from 65.7% to 5.7% (p?p?=?0.671); newborns with very low weight from 34.2% to 0 (p?p p?=?402); late fetal mortality from 63.1% to 0 (p?p?p?=?0.234); newborns with very low weight from 68.4% to 15.7% (p?p?相似文献   

Physical exercise is required for environmental enrichment to offset the quantitative effects of dark-rearing on the S-100β astrocytic density in the rat visual cortex

After birth, exposure to visual inputs modulates cortical development, inducing numerous changes in all of the components of the visual cortex. Most of the cortical changes thus induced occur during what is called the critical period. Astrocytes play an important role in the development, maintenance and plasticity of the cortex as well as in the structure and function of the vascular network. Visual deprivation induces a decrease in the astroglial population, whereas enhanced experience increases it. Exposure to an enriched environment has been shown to prevent the effects of dark‐rearing in the visual cortex. Our purpose was to study the effects of an enriched environment on the density of astrocytes per reference surface at the visual cortex of dark‐reared rats, in order to determine if enhanced experience is able to compensate the quantitative effects of visual deprivation and the role of physical exercise on the enrichment paradigm. Pregnant Sprague‐Dawley rats were raised in one of the following rearing conditions: control rats with standard housing (12‐h light/dark cycle); in total darkness for the dark‐rearing experiments; and dark‐rearing in conditions of enriched environment without and with physical exercise. The astrocytic density was estimated by immunohistochemistry for S‐100β protein. Quantifications were performed in layer IV. The somatosensorial cortex barrel field was also studied as control. The volume of layer IV was stereologically calculated for each region, age and experimental condition. From the beginning of the critical period, astrocyte density was higher in control rats than in the enriched environment group without physical exercise, with densities of astrocytes around 20% higher at all of the different ages. In contrast, when the animals had access to voluntary exercise, densities were significantly higher than even the control rats. Our main result shows that strategies to apply environmental enrichment should always consider the incorporation of physical exercise, even for sensorial areas such as the visual area, where complex enriched experience by itself is not enough to compensate the effects of visual deprivation.