Human leucocyte antigen profile in patients with aids and cytomegalovirus retinitis with and without macular involvement

Introduction: Cytomegalovirus retinitis is one of AIDS ocular manifestations. The objective of the present study was to determine possible associations between class I and II HLA antigens and alleles in patients with AIDS and cytomegalovirus retinitis (CMV-R) with macular involvement.Method: The study population consisted of 22 patients with AIDS and CMV-R with macular involvement (Group I), 19 patients with AIDS and CMV-R without macular involvement (Group II), and 202 individuals with negative serology for human immunodeficiency virus (Group III - control). Class I HLA antigens were typed by classical serology. Class II alleles were identified using sequence-specific oligonucleotide primers hybridized with amplified DNA. Results: HLA-DRB1*14 and  HLA-DRB1*10 specificities were more frequent among patients with macular involvement, possibly indicating greater susceptibility to this condition. In contrast, the HLA-B35 antigen may be associated with protection against macular involvement since it was significantly more frequent among patients without this involvement.Conclusions: The HLA-DRB1*14 and HLA-DRB1*10  alleles may favor the development of CMV-R with macular involvement, whereas the HLA-B35 subtype may be associated with protection against macular involvement

Effects of exercise training on atrophy gene expression in skeletal muscle of mice with chronic allergic lung inflammation

We evaluated the effects of chronic allergic airway inflammation and of treadmill training (12 weeks) of low and moderate intensity on muscle fiber cross-sectional area and mRNA levels of atrogin-1 and MuRF1 in the mouse tibialis anterior muscle. Six 4-month-old male BALB/c mice (28.5 ± 0.8 g) per group were examined: 1) control, non-sensitized and non-trained (C); 2) ovalbumin sensitized (OA, 20 µg per mouse); 3) non-sensitized and trained at 50% maximum speed _ low intensity (PT50%); 4) non-sensitized and trained at 75% maximum speed _ moderate intensity (PT75%); 5) OA-sensitized and trained at 50% (OA+PT50%), 6) OA-sensitized and trained at 75% (OA+PT75%). There was no difference in muscle fiber cross-sectional area among groups and no difference in atrogin-1 and MuRF1 expression between C and OA groups. All exercised groups showed significantly decreased expression of atrogin-1 compared to C (1.01 ± 0.2-fold): PT50% = 0.71 ± 0.12-fold; OA+PT50% = 0.74 ± 0.03-fold; PT75% = 0.71 ± 0.09-fold; OA+PT75% = 0.74 ± 0.09-fold. Similarly significant results were obtained regarding MuRF1 gene expression compared to C (1.01 ± 0.23-fold): PT50% = 0.53 ± 0.20-fold; OA+PT50% = 0.55 ± 0.11-fold; PT75% = 0.35 ± 0.15-fold; OA+PT75% = 0.37 ± 0.08-fold. A short period of OA did not induce skeletal muscle atrophy in the mouse tibialis anterior muscle and aerobic training at low and moderate intensity negatively regulates the atrophy pathway in skeletal muscle of healthy mice or mice with allergic lung inflammation.FAPESPCNP

Vibrio parahaemolyticus and Vibrio vulnificus in South America: water, seafood and human infections

The bacterial species, Vibrio parahaemolyticus and Vibrio vulnificus, are ubiquitous in estuaries and coastal waters throughout the world, but they also happen to be important human pathogens. They are concentrated by filter-feeding shellfish which are often consumed raw or undercooked, providing an important potential route of entry for an infective dose of these bacteria. Vibrio parahaemolyticus can cause abdominal cramping, nausea, diarrhoea, vomiting, chills and fever. Vibrio vulnificus can cause similar gastrointestinal-related symptoms, but can also spread to the bloodstream, resulting in primary septicaemia, and it can also cause disease via wound infections. The objective of this article is to summarize, for the first time, the incidence and importance of V. parahaemolyticus and V. vulnificus in South America, in environmental waters and seafood, especifically molluscan shellfish, as well as human infection cases and outbreaks. It appears that infections from V. parahaemolyticus have been more strongly related to shellfish ingestion and have been more frequently reported on the Pacific coast of South America. Conversely, V. vulnificus has been more frequently acquired by water contact with open wounds and its presence has been more heavily reported along the Atlantic coast of South America, and while documented to cause serious mortality, have been relatively few in number. The impacts of El Nino Southern Oscillation (ENSO) have been observed to cause an increase in V. parahaemolyticus outbreaks on the Pacific coast of South America. The implementation of a regulated monitoring approach, along with the use of faster, more accurate and virulence-specific detection approaches, such as PCR confirmation, should be considered to detect the presence of pathogenic Vibrio strains in environmental and seafood samples for protection of public health. Furthermore, improved clinical surveillance with suspected cases should be implemented. This review highlights the need for more research and monitoring of vibrios in South America, in water, shellfish and clinical samples

The emergence of the cortisol circadian rhythm in monozygotic and dizygotic twin infants: the twin-pair synchrony

OBJECTIVE: Studies on the influence of genetic factors on the ontogeny of cortisol circadian rhythm in infants are lacking. This study evaluated the influence of twinning and the heritability on the age of emergence of salivary cortisol rhythm. DESIGN AND SUBJECTS: A longitudinal study was performed using salivary samples obtained during morning and night, at 2, 4, 8, 12, 16, 20 and 24 weeks of postnatal life in 34 infants, 10 monozygotic (MZ) and 7 dizygotic (DZ) twin pairs. Salivary cortisol was determined by radioimmunoassay (RIA). Zigosity was verified by DNA analysis of at least 13 short tandem repeat polymorphisms. Difference of the emergence of cortisol circadian rhythm, within each twin pair, the intraclass correlation coefficient and the heritability index (h(2)) were calculated. RESULTS: The mean (± SEM) age of emergence of salivary cortisol circadian rhythm was similar in MZ and DZ (7·8 ± 1·0 vs 7·4 ± 1·3 weeks). Seven pairs showed coincidence of the emergence of cortisol rhythm. Ten pairs were not coincident; among them the within-pair difference of emergence of salivary circadian rhythm was similar in both MZ and DZ groups. The intraclass correlation coefficients were rMZ = 0·60, P = 0·02; and rDZ = 0·65, P = 0·03, respectively. The heritability index (h(2)) was 0·21 (ns). CONCLUSIONS: Salivary circadian rhythm appeared at the same postnatal age in MZ and DZ twin infants. Although several physiological aspects might be involved, the heritability index, obtained in the present study, suggests less genetic than environmental impact on the age of the onset of the cortisol circadian rhythm. Our data also indicated that each twin-pair show synchrony because they probably shared prenatal and postnatal environmental synchronizers

Cryo-EM captures early ribosome assembly in action

Ribosome biogenesis is a fundamental multi-step cellular process in all domains of life that involves the production, processing, folding, and modification of ribosomal RNAs (rRNAs) and ribosomal proteins. To obtain insights into the still unexplored early assembly phase of the bacterial 50S subunit, we exploited a minimal in vitro reconstitution system using purified ribosomal components and scalable reaction conditions. Time-limited assembly assays combined with cryo-EM analysis visualizes the structurally complex assembly pathway starting with a particle consisting of ordered density for only ~500 nucleotides of 23S rRNA domain I and three ribosomal proteins. In addition, our structural analysis reveals that early 50S assembly occurs in a domain-wise fashion, while late 50S assembly proceeds incrementally. Furthermore, we find that both ribosomal proteins and folded rRNA helices, occupying surface exposed regions on pre-50S particles, induce, or stabilize rRNA folds within adjacent regions, thereby creating cooperativity

Fluorinated Ionic Liquids as Task-Specific Materials: An Overview of Current Research

This chapter is focused on the massive potential and increasing interest on Fluorinated Ionic Liquids (FILs) as task-specific materials. FILs are a specific family of ionic liquids, with fluorine tags equal or longer than four carbon atoms, that share and improve the properties of both traditional ionic liquids and perfluoro surfactants. These compounds have unique properties such as three nanosegregated domains, a great surfactant power, chemical/biological inertness, easy recovery and recyclability, low surface tension, extreme surface activity, high gas solubility, negligible vapour pressure, null flammability, and high thermal stability. These properties allied to the countless possible combinations between cations and anions allow the design and development of FILs with remarkable properties to be used in specific applications. In this review, we highlight not only the unique thermophysical, surfactant and toxicological properties of these fluorinated compounds, but also their application as task-specific materials in many fields of interest, including biomedical applications, as artificial gas carries and drug delivery systems, as well as solvents for separations in engineering processes

Alkali extraction of archaeological and geological charcoal: evidence for diagenetic degradation and formation of humic acids

Charcoal forms a crucial source of archaeological and palaeoenvironmental data, providing a record of cultural activities, past climatic conditions and a means of chronological control via radiocarbon (<sup>14</sup>C) dating. Key to this is the perceived resistance of charcoal to post-depositional alteration, however recent research has highlighted the possibility for alteration and degradation of charcoal in the environment. An important aspect of such diagenesis is the potential for addition of exogenous 'humic acids' (HAs), to affect the accuracy of archaeological and palaeoenvironmental reconstructions based upon chemical analyses of HA-containing charcoal. However the release of significant quantities of HA from apparently pristine charcoals raises the question whether some HA could be derived via diagenetic alteration of charcoal itself. Here we address this question through comparison of freshly produced charcoal with samples from archaeological and geological sites exposed to environmental conditions for millennia using elemental (C/H/O) and isotopic (δ<sup>13</sup>C) measurements, Fourier Transform Infrared Spectroscopy (FTIR) and proton Liquid-State Nuclear Magnetic Resonance (<sup>1</sup>H NMR). The results of analyses show that the presence of highly carboxylated and aromatic alkali-extractable HA in charcoal from depositional environments can often be attributable to the effects of post-depositional processes, and that these substances can represent the products of post-depositional diagenetic alteration in charcoal

Variability in oxidative degradation of charcoal: influence of production variables and environmental exposure

<p>Charcoal is a key component of the Black Carbon (BC) continuum, where BC is characterized as a recalcitrant, fire-derived, polyaromatic material. Charcoal is an important source of palaeoenvironmental data, and of great interest as a potential carbon sink, due to its high apparent environmental stability. However, at least some forms of charcoal are clearly susceptible to environmental alteration and degradation over relatively short timescales. Although these processes have importance for the role of charcoal in global biogeochemistry, they remain poorly understood.</p> <p>Here we present results of an investigation into the susceptibility of a range of charcoal samples to oxidative degradation in acidified potassium dichromate. The study examines both freshly-produced charcoal, and charcoal exposed to environmental conditions for up to 50,000 years. We compare the proportion of carbon present in different forms between the samples, specifically with respect to the relative chemical resistance of these forms. This was undertaken in order to improve understanding of the post-depositional diagenetic changes affecting charcoal within environmental deposits.</p> <p>A wide range in chemical compositions are apparent both within and between the sample groups. In freshly-produced charcoal, material produced at 300 °C contains carbon with more labile forms than charcoal produced at ≥400 °C, signifying a key chemical change over the 300–400 °C temperature range. Charcoal exposed to environmental depositional conditions is frequently composed of a highly carboxylated aromatic structure and contains a range of carbon fractions of varying oxidative resistance. These findings suggest that a significant number of the environmental charcoals have undergone post-depositional diagenetic alteration. Further, the data highlight the potential for the use of controlled progressive oxidative degradation as a method to characterize chemical differences between individual charcoal samples.</p&gt