Membrane insertion and topology of the p7B movement protein of Melon Necrotic Spot Virus (MNSV)

Cell-to-cell movement of the Melon Necrotic Spot Virus (MNSV) is controlled by two small proteins working in trans, an RNA-binding protein (p7A) and an integral membrane protein (p7B) separated by an amber stop codon. p7B contains a single hydrophobic region. Membrane integration of this region was observed when inserted into model proteins in the presence of microsomal membranes. Furthermore, we explored the topology and targeting mechanisms of full-length p7B. Here we present evidence that p7B integrates in vitro into the ER membrane cotranslationally and with an Nt-cytoplasmic/Ct-luminal orientation. The observed topology was monitored in vivo by fusing GFP to the Ct of p7B, enabling the overexpression in Escherichia coli cultures. Finally, the topology of a putative p14 movement protein was established by replacing the amber stop codon located between p7A and p7B.     

Acceptability of children's testing for HIV infection during routine care activities in the Pediatrics Department of Sourô Sanou Teaching Hospital in Bobo-Dioulasso (Burkina Faso)

Background

In order to contribute to the fight against the pediatric HIV infection, we have assessed, through a study in which we have systematically proposed to carry out children's testing, the rate of acceptability and the feasibility of children's HIV testing during the routine activities of the department. We have also analyzed the reasons for the acceptability or the refusal of the child's HIV testing by the accompanying person.

Prevalence of human papillomavirus in squamous cell carcinoma of the tongue

Oncogenic human papillomaviruses (HPVs) are important agents in the genesis of gynecological cancer, and have also been implied in the genesis of oral cancer. With the purpose of evaluating the relationship between HPV and squamous cell carcinoma (SCC) of the tongue, a case-control study was performed. Fifty white male patients who were smokers and had the histological diagnosis of SCC of the tongue were selected. The control group was composed of 10 matched patients with no clinical evidence of tongue lesions. Polymerase chain reaction (PCR) was used to detect the presence of HPV genome in fresh-frozen tissue specimens from SCC of the tongue margin. Thirty-seven patients (74%) had a positive PCR for oncogenic papillomavirus, and only 1 specimen (10%) of the control group was positive for nononcogenic papillomavirus. Based on the statistical analysis of this study there was a 25.6% higher risk for SCC of the tongue to harbor oncogenic HPV than the healthy control tongue tissue.     

An Intracellular Antioxidant Determines the Expression of a Melanin-Based Signal in a Bird

To understand how traits used in animal communication evolved and are maintained as honest signals, we need to understand the mechanisms that prevent cheating. It has been proposed that honest signaling is guaranteed by the costs associated with the signal expression. However, the nature of these costs is still under debate. Melanin-based signals are intriguing because their expression seems to be tightly controlled by genes and the resource involved (i.e. melanin) seems to be not limited. However, in vertebrates, low levels of a key intracellular antioxidant (i.e. glutathione) are needed to promote melanogenesis. We propose that melanin-based ornaments can signal the ability to cope with oxidative stress because those individuals with low enough levels of glutathione, such as those required for melanin production, should manage well the whole of the antioxidant machinery in order to maintain a certain oxidative status. We analysed the expression of a melanin-based signal: the well-known black stripe of the great tit (Parus major). Great tit nestlings were injected with a specific inhibitor of glutathione production (DL-buthionine-S,R-sulfoximine; BSO) throughout their development. BSO effectively decreased intracellular glutathione levels without apparent side effects on growth or body condition. Instead, treated nestlings developed black breast stripes 70–100% larger than controls. Moreover, treated nestlings also compensated the decrease in glutathione levels by increasing the levels of circulating antioxidants. Results indicate that melanin-based signals can be at least partially permeable to environmental influences such as those associated to oxidative stress. They also reveal a potential handicap associated to the expression of this kind of signals. Finally, although other contributing factors could have been present, our findings emphasize the role of oxidative stress in shaping the evolution of animal signals in general and, in particular, those produced by pigments.     

Comparison of vitreoretinal disorders in fellow eyes of lamellar macular holes versus epiretinal membrane foveoschisis

Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate and compare the rate and characteristics of vitreoretinal disorders in fellow eyes of lamellar macular holes (LMH)...     

Temporary and definitive external fixation of war injuries: use of a French dedicated fixator

Purpose

External fixation is the recommended stabilization method for both open and closed fractures of long bones in forward surgical hospitals. Specific combat surgical tactics are best performed using dedicated external fixators. The Percy Fx© (Biomet) fixator was developed for this reason by the French Army Medical Service, and has been used in various theatres of operations for more than ten years.

Methods

The tactics of Percy Fx© (Biomet) fixator use were analysed in two different situations: for the treatment of French soldiers wounded on several battlefields and then evacuated to France and for the management of local nationals in forward medical treatment facilities in Afghanistan and Chad.

Results

Overall 48 externals fixators were implanted on 37 French casualties; 28 frames were temporary and converted to definitive rigid frames or internal fixation after medical evacuation. The 77 Afghan patients totalled 85 external fixators, including 13 temporary frames applied in Forward Surgical Teams (FSTs) prior to their arrival at the Kabul combat support hospital. All of the 47 Chadian patients were treated in a FST with primary definitive frames because of delayed surgical management and absence of higher level of care in Chad.

Conclusion

Temporary frames were mostly used for French soldiers to facilitate strategic air medical evacuation following trauma damage control orthopaedic principles. Definitive rigid frames permitted achieving treatment of all types of war extremity injuries, even in poor conditions.     

Molecular diagnosis of resistance to antimalarial drugs during epidemics and in war zones

Plasmodium falciparum mutations pfcrt K76T and the dhfr/dhps "quintuple mutant" are molecular markers of resistance to chloroquine and sulfadoxine-pyrimethamine, respectively. During an epidemic of P. falciparum malaria in an area of political unrest in northern Mali, where standard efficacy studies have been impossible, we measured the prevalence of these markers in a cross-sectional survey. In 80% of cases of infection, pfcrt K76T was detected, but none of the cases carried the dhfr/dhps quintuple mutant. On the basis of these results, chloroquine was replaced by sulfadoxine-pyrimethamine in control efforts. This example illustrates how molecular markers for drug resistance can provide timely data that inform malaria-control policy during epidemics and other emergency situations.     

Does methylene blue detect intestinal metaplasia in Barrett's esophagus?

BACKGROUND: Methylene blue has been used to selectively stain areas of specialized intestinal metaplasia in Barrett's esophagus. The sensitivity, specificity, and negative and positive predictive values for the detection of specialized intestinal metaplasia by methylene blue chromoendoscopy were determined in patients with Barrett's esophagus. METHODS: Thirty patients with Barrett's esophagus underwent endoscopy with biopsy specimens obtained from areas that stained positive and negative with methylene blue. Histopathologic findings were compared with methylene blue chromoendoscopy findings. RESULTS: Two hundred ninety-two biopsy specimens (mean 9.7/patient) were obtained: 203 from stained and 89 from unstained areas. Sensitivity, specificity, and negative and positive predictive values for detection of specialized intestinal metaplasia were, respectively, 72%, 46%, 22%, and 89%. Comparing 187 biopsy specimens from patients with long-segment Barrett's esophagus with 105 specimens from patients with short-segment Barrett's esophagus, the sensitivity, specificity, and negative and positive predictive values were, respectively, 77% versus 63% (p = 0.044), 79% versus 21% (p < 0.002), 28% versus 14% (p = 0.219), and 97% versus 73% (p < 0.002). The odds ratio for detection of specialized intestinal metaplasia in stained areas was 12.40 in long-segment and 0.45 in short-segment Barrett's esophagus. CONCLUSIONS: Data from this study confirm the value of methylene blue chromoendoscopy for detection of specialized intestinal metaplasia in long-segment Barrett's esophagus, but not in short-segment Barrett's esophagus.