In vitro specificity of EcoRI DNA methyltransferase.

The sequence selectivity of enzyme-DNA interactions was analyzed by comparing discrimination between synthetic oligonucleotides containing the canonical site GAATTC and altered DNA sequences with the EcoRI DNA methyltransferase. The specificities (kcat/KmDNA) are decreased from 5- to 23,000-fold relative to the unmodified site. For several substrates the decrease in kcat makes a disproportionate contribution to the specificity difference, suggesting that discrimination is mediated by the placement of critical catalytic residues rather than binding interactions. This is supported by our observation that specificity changes are generally not followed by changes in the stability of the methyltransferase-DNA complexes. Also, base pair substitutions near the site of methylation result in greater decreases in complex stability, suggesting that recognition and catalytic mechanisms overlap.     

Oil and gas development in the World Heritage and wider protected area network in sub-Saharan Africa

More than 25% of natural World Heritage (WH) sites worldwide are estimated to be under pressure from existing or future mining and energy activities (IUCN 2008; UNESCO 2009). However, that ‘pressure’ has yet to be quantitatively defined and assessed for many regions of the world. We conducted a GIS-based analysis of overlap and proximity between natural WH sites and areas allocated to oil and gas concessions as well as pipelines and oil wells for all of sub-Saharan Africa. We found that oil and gas concessions were located within 27% of the WH sites, though no currently active oil wells were operating directly within the WH sites. A proximity-based assessment of oil and gas concessions within 5 km of WH site boundaries included only one additional WH site, suggesting that sites susceptible to indirect impacts from oil and gas development are likely to be those already overlapped by concessions. Our findings indicate that activity from oil and gas development in sub-Saharan WH sites has to date been limited; however, future pressure cannot be ruled out, due to continued presence of concessions within more than one quarter of the network, and projected expansion of oil and gas exploration within the region. Our results may be used to inform the inclusion of new sites into the WH network.     

Human plasma glycome in attention-deficit hyperactivity disorder and autism spectrum disorders

Over a half of all proteins are glycosylated, and their proper glycosylation is essential for normal function. Unfortunately, because of structural complexity of nonlinear branched glycans and the absence of genetic template for their synthesis, the knowledge about glycans is lagging significantly behind the knowledge about proteins or DNA. Using a recently developed quantitative high throughput glycan analysis method we quantified components of the plasma N-glycome in 99 children with attention-deficit hyperactivity disorder (ADHD), 81 child and 5 adults with autism spectrum disorder, and a total of 340 matching healthy controls. No changes in plasma glycome were found to associate with autism spectrum disorder, but several highly significant associations were observed with ADHD. Further structural analysis of plasma glycans revealed that ADHD is associated with increased antennary fucosylation of biantennary glycans and decreased levels of some complex glycans with three or four antennas. The design of this study prevented any functional conclusions about the observed associations, but specific differences in glycosylation appears to be strongly associated with ADHD and warrants further studies in this direction.     

A study of nine polymorphic systems in the population of the Po Delta

The present work reports a study of nine genetic polymorphic systems in the area of the Po Delta where malaria was endemic since the XIV century. Our data confirm some characteristics of this population already reported by other authors such as the high prevalence of thalassemia, the low prevalence of the rh (d) gene and the presence of G-6-PD deficiency. Among the other systems studied, i.e., AP, PGM₁ ADA and AK, only AP frequencies of Po Delta population are significantly different from those of other continental Italian populations, the P^C allele showing the lowest frequency so far observed.     

Induction of erythroid differentiation of human K562 cells by 3-O-acyl-1,2-O-isopropylidene-D-glucofuranose derivatives

In this paper we report the synthesis of twelve 3-O-acyl-1,2-O-isopropylidene-D-glucofuranose derivatives and the results obtained on their effects in inducing erythroid differentiation of human leukemic K562 cells. The data obtained demonstrate that two of the newly synthetized compounds are able to induce erythroid differentiation of K562 cells. In addition, these same compounds potentiate K562 erythroid differentiation induced by cytosine arabinoside, retinoic acid and mithramycin. Inducers of erythroid differentiation stimulating fetal gamma-globin synthesis could be considered for possible use in the experimental therapy of hematological diseases associated with a failure in the expression of adult beta-globin genes.     

The genotoxicity of nitrilotriacetic acid (NTA) in a somatic mutation and recombination test in Drosophila melanogaster

The genotoxicity of a chelating agent, the trisodium salt of nitrilotriacetic acid (NTA), was assessed in a somatic mutation and recombination test (SMART) in Drosophila melanogaster employing the wing hair markers mwh and flr3. The experiments were performed in parallel in two different laboratories (Padua, Italy and Schwerzenbach, Switzerland). The effectively absorbed doses of NTA, which was administered by feeding to larvae, were determined by a sensitive method employing [3H]leucine which allowed individual consumption levels to be measured. The particular pattern of clone induction produced by this compound suggests that NTA is active in inducing mitotic recombination and possibly aneuploidy in somatic cells of Drosophila. This is discussed in relation to the data present in the literature regarding the genotoxicity of NTA in a variety of experimental systems.     

Body mass index and nutritional status of the Bayash Roma from eastern Croatia

This study examines anthropometrically assessed nutritional status of the Bayash, the Roma population from the eastern Croatian region of Baranya, and compares it to the non-Roma general population of eastern Croatia. The analysis of nutritional status and diets is a segment of multidisciplinary anthropological and epidemiological survey of the Roma minority population in Croatia began in 2005. The Bayash are an ethnic group that arrived to Croatia from Romania most likely in the 19th century and speaks a distinct archaic dialect of the Romanian language. The Roma population of Baranya approximates 1,000 according to the 2001 census. The Bayash sample comprised 227 adults aged 18-65yrs. The women fall below the Croatian 10th percentile for stature and men track about the 10th percentile. Both sexes approximate the 25th percentile for body weight. Despite their diminutive size, the Bayash appear to have adequate nutritional status until the age of 35yrs after which their average BMI exceeds the value of 25 kg/m(2) and falls in the overweight category. However, 8% of Bayash are underweight (BMI<18.5) in contrast to 1% of the majority population in the region. Underweight rates are especially high in women (11%) compared to men (4%). The prevalence of overweight (BMI 25.0 to 29.9) of 30% is considerably lower than in the majority population (42%) while the prevalence of obesity (BMI>or=30.0) of 23% is approximately equal. Overall unsatisfactory nutritional status of the Bayash merits attention. It appears to be the product of unhealthy dietary habits and their socio-economic deprivation that resulted from their poor education and extremely high unemployment.     

Extramedullary plasmacytoma imitating neoplasm of the gallbladder fossa after cholecystectomy

Extramedullary plasmacytomas are plasma cell tumors that arise outside of the bone marrow. They account for approximately 3% of plasma cell neoplasms and are most frequently located in the head and neck region. Five months after undergoing cholecystectomy, a 69-year-old patient presented with the pain under the right costal margin and a 12 kg weight loss. Computed tomography of the abdomen demonstrated irregular, vascular mass in the gallbladder fossa that dents towards the duodenum and the pylorus and lowers caudally to the hepatic flexure. His laboratory tests indicated normocytic anemia and showed elevated sedimentation rate. During operative procedure, a tumorous mass in the gallbladder fossa was found, inseparable of the peritoneum of the hepatoduodenal ligament and the IVb liver segment. Histopathological examination and immunohistochemical staining determined the diagnosis of the plasmacytoma. Total resection of the tumor was achieved and after 24-month follow-up patient showed no signs of local recurrence or dissemination of the disease.     

Human immunodeficiency virus seroprevalence among inmates of the penitentiary complex of the region of campinas, state of S?o Paulo, Brazil.

Six hundred and ninety three male inmates from three penitentiaries, two (A and B) maximum-security systems and one (C) minimum-security facility, located in Campinas, State of S?o Paulo, Brazil were studied for the presence of human immunodeficiency virus (HIV) antibodies, using a cross-sectional design. The search for anti-HIV antibodies in 693 samples of sera collected was carried out by two serological tests: (a) the Microparticle enzyme immunoassay-HIV-1 and HIV-2 (MEIA) (Abbott Laboratories) and (b) the Western Blot-HIV-1 (WB) (Cambridge Biotech Corporation) to confirm positive results with MEIA. Sera reactivity for HIV antibodies was 14.4%. The highest frequency of anti-HIV antibodies was found in the A and B maximum-security prisons: 17% and 21.5%, respectively. In prison C, the frequency of reagents was 10.9%. Seventy three inmates, initially negative in the MEIA test, were checked again five and seven months later. Three of them, all from the maximum-security facilities, became reactive in the MEIA test, with confirmation in the WB, suggesting that serological conversion had occurred after imprisonment.