Histological study of the protective effect of melatonin on neural cells after neonatal hypoxia-ischemia

To minimize as much as possible the neurological consequences from hypoxic-ischemic (HI) brain injury, neuroprotective strategies are urgently required. In this sense, there is growing interest in the neuroprotective potential of melatonin after perinatal asphyxia, due to its high efficacy, low toxicity and ready cross through the blood-brain barrier. Twenty six Wistar rats at postnatal day 7 were randomly assigned to: two hypoxic-ischemic groups: pups with the left common carotid artery ligated and then submitted to hypoxia (HI group) and animals that received a dose of 15 mg/kg melatonin just after the hypoxic-ischemic event and repeated twice with an interval of 24 hours (HI+MEL group). Pups without ischemia or hypoxia were used as controls (Sham group). Seven days after surgery, brains were collected and coronal sections Nissl-stained, TUNEL-labeled, or MBP- and GFAP-immunolabeled prior to determining brain infarct area, quantify surviving neurons and evaluate oligodendroglial injury and reactive astrogliosis. The number of surviving neurons showing a well preserved architecture in HI+MEL group was similar to that observed in the Sham group. Moreover, TUNEL-positive cells only appeared in the HI group. The ratio of left-to-right hemispheric MBP immunostaining showed a significant decrease in the HI group in comparison with Sham pups, which was restored after melatonin administration. Melatonin also reduced reactive gliosis. Thus, our results suggest that treatment with melatonin after neonatal hypoxia-ischemia led to a neuroprotective effect reducing cell death, white matter demyelination and reactive astrogliosis.

Comparison of two methods of reciprocal recurrent selection in maize (Zea mays L.)

Reciprocal recurrent selection (RRS) was proposed for simultaneously improving two populations and their cross. A modification of the classical full-sib RRS (FS-RRS) was proposed in which the performance of full-sibs and S(2) families is combined in a selection index (FS-S(2)-RRS). The Mediterranean corn borer (MCB) is the main corn borer species in the Mediterranean and adjacent areas and produces important yield losses. We started two RRS programs (FS-RRS and FS-S(2)-RRS) from the same maize population in which the selection criterion was grain yield under artificial infestation with MCB eggs. Original populations, two cycles of selection derived from them by both RRS methods, and population crosses were evaluated under MCB attack and under insecticide treatment in three different environments. The objective was to compare the efficiency of the FS-RRS and the FS-S(2)-RRS methods for improving grain yield. We found that the FS-S(2)-RRS method was successful for improving the yield of the population cross under optimum conditions (the regression coefficient over cycles was b = 0.87** Mg ha(-1) cycle(-1)) without losing yield under high pressure of MCB attack (b = 0.07). On the contrary, FS-RRS failed to improve the yield of the population cross under optimum conditions (b = 0.65) and tended to decrease the yield under high levels of MCB attack (b = -0.26). We conclude that for developing high yielding and stable varieties, FS-S(2)-RRS is more efficient than the classical FS-RRS method.

[Characteristics of human immunodeficiency virus-1 infected children receiving highly active antiretroviral therapy: a cross-sectional study]

INTRODUCTION

Since 1996, when HAART became available, there has been a change in the course of HIV-infection, leading it to become a chronic disease. Our aim was to describe the characteristics of the children followed up in our hospital.

PATIENTS AND METHODS

A cross-sectional study was conducted on 32 HIV-infected children followed up until December-2010, at the University-Hospital de Getafe. Clinical and laboratory information from the last visit was collected for the evaluation of patients.

RESULTS

Thirty-two children with HIV-1 were evaluated, 29 infected through vertical-transmission. The median age was 14 years. According to the CDC classification, 56% (18/32) of children were in category A, 28% (9/32) B and 16% (5/32) C. Immunological class was 3 in 75% of children, class 2 in 9% and class 1 in 16%. The median nadir of CD4 was 337 cells/ml (12%). The median current CD4 was 749 (31%). Only one adolescent had a CD4% below 200 cells/ml due to lack of adherence. Twenty-eight patients (87%) were receiving HAART, and 4 patients were off antiretroviral treatment. Among the patients treated, 26 (93%) had viral loads <200 copies/ml. The median viral-load was<20 copies/ml. Median time on antiretroviral treatment was 10 years. The combination more frequently used was two nucleoside reverse transcriptase inhibitors (NRTI) and one protease inhibitor (PI), that was given to 15 patients (47%), followed by 2 NRTI, and one non-nucleoside reverse transcriptase inhibitor (NNRTI) in 8 patients (29%). Two children received rescue therapy including raltegravir, one with tipranavir and the other with darunavir. A total of 12 patients (43%) received medication once a day, 7 of them with fixed-dose combinations in a single tablet (25%). There were metabolic complications, including hyperlipidaemia or lipodystrophy were observed in 17 children (53%).

CONCLUSIONS

Most of our patients are receiving HAART, with good virological and immunological control. The prevalence of metabolic abnormalities was high. Strategies to improve adherence and decrease toxicities are needed in perinatally-acquired HIV-infected children.

Anterior segment changes following intravitreal bevacizumab injection for treatment of neovascular glaucoma

BACKGROUND

The purpose of this study was to describe anterior segment changes in a prospective, interventional, noncomparative case series of patients with neovascular glaucoma secondary to proliferative diabetic retinopathy treated with intravitreal bevacizumab.

METHODS

Five consecutive patients with neovascular glaucoma and a refractory, symptomatic elevation of intraocular pressure and pronounced anterior segment congestion received intravitreal bevacizumab 1.25 mg/0.05 mL. Follow-up examinations were performed at 4-16 weeks by the same specialists, with testing performed at hour 48, week 1, and months 1, 3, and 6 after intravitreal bevacizumab.

RESULTS

We observed a significant difference (P = 0.021) between initial and mean neovascularization at three months in all the quadrants. At three months, median intraocular pressure was 19 ± 5.38 (range 12-26) mmHg. In three of the five cases, diode laser cyclophotocoagulation was required, and in one case a trabeculectomy was performed. One patient showed complete synechial angle closure 48 hours after treatment which required cyclodestructive procedures to normalize intraocular pressure.

CONCLUSION

Intravitreal bevacizumab achieves complete regression of neovascularization in neovascular glaucoma secondary to proliferative diabetic retinopathy, and this regression is stable when associated with treatment of the underlying disease and should be investigated more thoroughly as an adjunct in the management of neovascular glaucoma.

Effectiveness of a PMTCT programme in rural Western Kenya

We assess the coverage of a Prevention of Mother-to-child Transmission (PMTCT) programme in Busia (Kenya) from 1 January 2006 to 31 December 2008 and estimate the risk of transmission of HIV. We also estimate the odds of HIV transmission according to pharmacological intervention received. Programme coverage was estimated as the proportion of mother-baby pairs receiving any antiretroviral (ARV) regimen among all HIV-positive women attending services. We estimated the mother-to-child transmission (MTCT) rate and their 95% confidence interval (95%CI) using the direct method of calculation (intermediate estimate). A case-control study was established among all children born to HIV-positive mothers with information on outcome (HIV status of the babies) and exposure (data on pharmacological intervention). Cases were all HIV-positive children and controls were the HIV-negative ones. Exposure was defined as: (1) complete protocol: ARV prescribed according World Health Organisation recommendations; (2) partial protocol: does not meet criteria for complete protocol; and (3) no intervention: ARVs were not prescribed to both mother and child. Babies were tested using DNA Polymerase Chain Reaction at six weeks of life and six weeks after breastfeeding ceased. In the study period, 22,566 women accepted testing, 1668 were HIV positive (7.4%; 95%CI 7.05-7.73); 1036 (62%) registered in the programme and 632 were lost. Programme coverage was 40.4% (95%CI 37.9-42.7). Out of the 767 newborns, 28 (3.6%) died, 148 (19.3%) defaulted, 282 (36.7%) were administratively censored and 309 (40.2%) babies completed the follow-up as per protocol; 49 were HIV positive and MTCT risk was 15.86% (95%CI 11.6-20.1). The odds of having an HIV-positive baby was 4.6 times higher among pairs receiving a partial protocol compared to those receiving a complete protocol and 43 times higher among those receiving no intervention. Our data show a good level of enrolment but low global coverage rate. It demonstrates that ARV regimens can be implemented in low resource rural settings with marked decreases of MTCT. Increasing the coverage of PMTCT programmes remains the main challenge.

Experience of the Reina Sofia hospital in lobar lung transplantation

The number of patients awaiting lung transplantation has steadily increased over the past decade, but the number of donors has remained relatively stable. Owing to the increasing scarcity of donor lungs, especially for pediatric and small adult recipients, advanced operative strategies for the use of larger grafts for smaller recipients have been developed. Size matching between donors and recipients represents one of the organ distribution criteria widely accepted by lung transplantation teams. However, in some cases it is not possible to allocate a donor to the corresponding size-compatible recipient. To avoid possible complications derived from the implantation of oversized lungs into smaller recipients, various methods of downsizing are applied for cadaveric donor lungs, such as lobar transplantation. We review our experience in 6 patients undergoing volume reduction of the lung graft by lobar resection at the time of transplantation. Graft volume reduction by anatomic resection (lobar transplantation) is a reliable and safe procedure to overcome size disparities between the donor and the recipient of a lung transplant, and thus to maximize the number of donors.

Results of lung transplantation in idiopathic pulmonary fibrosis patients

Lung transplantation (OLT) remains the only available therapy for patients with end-stage idiopathic pulmonary fibrosis (IPF). The objective of this study was to review our experience of OLT for end-stage IPF (IPFLT) patients, seeking to identify variables associated with survival for comparison with outcomes of other indications for LT (OILT). From October 1993 to December 2009, we performed 310 consecutive OLT in 301 patients for treatment of various end-stage pulmonary conditions. The indications for OLT were: IPF (n=89, 30.5%) chronic obstructive pulmonary disease (n=82), cystic fibrosis (n=80), bronchiectasis (n=12), alfa-1-antitrypsin deficit (n=6), primary pulmonary hypertension (n=4), bronchiolitis obliterans (n=4), other conditions (n=15). We observed significant differences in the actuarial survival between the IPFLT and the OILT groups particularly at the expense of worse perioperative 30-day and early 1-year mortality in the IPFLT group. Upon univariate and multivariate analyses, the need for cardiopulmonary bypass, previous recipient ventilator dependence, and donor age>50 years were all associated with poorer survival rates among IPF patients. In our experience, survival did not differ between patients who underwent a single versus a bilateral sequential lung transplant (BSLT); however, BSLT cases were associated with short-term damage but long-term survival. The functional results in the IPFLT group were excellent. We observed significant improvements in the values of arterial oxygen pressure (PaO2), arterial carbon dioxide pressure (PaCO2), forced vital capacity (FVC%) and forced expiratory volume in 1 second (FEV1%) at 6, 12, and 36 months compared to their pretransplant baseline results.

Enhanced oxidative stress and increased mitochondrial mass during efavirenz-induced apoptosis in human hepatic cells

BACKGROUND AND PURPOSE

Efavirenz (EFV) is widely used in the treatment of HIV-1 infection. Though highly efficient, there is growing concern about EFV-related side effects, the molecular basis of which remains elusive.

EXPERIMENTAL APPROACH

In vitro studies were performed to address the effect of clinically relevant concentrations of EFV (10, 25 and 50 microM) on human hepatic cells.

KEY RESULTS

Cellular proliferation and viability were reduced in a concentration-dependent manner. Analyses of the cell cycle and several cell death parameters (chromatin condensation, phosphatidylserine exteriorization, mitochondrial proapoptotic protein translocation and caspase activation) revealed that EFV triggered apoptosis via the intrinsic pathway. In addition, EFV directly affected mitochondrial function in a reversible manner, inducing a decrease in mitochondrial membrane potential and an increase in mitochondrial superoxide production, followed by a reduction in cellular glutathione content. The rapidity of these actions rules out any involvement of mitochondrial DNA replication, which, until now, was thought to be the main mechanism of mitochondrial toxicity of antiretroviral drugs. Importantly, we also observed an increase in mitochondrial mass, manifested as an elevated cardiolipin content and enhanced expression of mitochondrial proteins, which was not paralleled by an increase in the mtDNA/nuclear DNA copy number ratio. The toxic effect of EFV was partially reversed by antioxidant pretreatment, which suggests ROS generation is involved in this effect.

CONCLUSION AND IMPLICATIONS

Clinically relevant concentrations of EFV were shown to be mitotoxic in human hepatic cells in vitro, which may be pertinent to the understanding of the hepatotoxicity associated with this drug.