Dermatomycoses Caused by Nattrassia Mangiferae in São Paulo,Brazil

Nattrassia mangiferae formerly known as Hendersonula toruloidea,is a phaeoid coelomycete described by Nattrass in 1933. We report five casesof N. mangiferae infections in São Paulo, Brazil. This fungus wasisolated from interdigital lesions on the feet in one patient, toenails in threecases and fingernails in the other one. The infections were initially consideredto be caused by a dermatophyte. Although there are only a few cases describedin the medical literature, the five cases reported suggest that N. mangiferaeshould be taken into consideration in the differential diagnosis of tinea pedisinfections.     

Sleep assessment in a population-based study of chronic fatigue syndrome

Background

Chronic fatigue syndrome (CFS) is a disabling condition that affects approximately 800,000 adult Americans. The pathophysiology remains unknown and there are no diagnostic markers or characteristic physical signs or laboratory abnormalities. Most CFS patients complain of unrefreshing sleep and many of the postulated etiologies of CFS affect sleep. Conversely, many sleep disorders present similarly to CFS. Few studies characterizing sleep in unselected CFS subjects have been published and none have been performed in cases identified from population-based studies.

Methods

The study included 339 subjects (mean age 45.8 years, 77% female, 94.1% white) identified through telephone screen in a previously described population-based study of CFS in Wichita, Kansas. They completed questionnaires to assess fatigue and wellness and 2 self-administered sleep questionnaires. Scores for five of the six sleep factors (insomnia/hypersomnia, non-restorative sleep, excessive daytime somnolence, sleep apnea, and restlessness) in the Centre for Sleep and Chronobiology's Sleep Assessment Questionnaire^© (SAQ^©) were dichotomized based on threshold. The Epworth Sleepiness Scale score was used as a continuous variable.

Results

81.4% of subjects had an abnormality in at least one SAQ^© sleep factor. Subjects with sleep factor abnormalities had significantly lower wellness scores but statistically unchanged fatigue severity scores compared to those without SAQ^© abnormality. CFS subjects had significantly increased risk of abnormal scores in the non-restorative (adjusted odds ratio [OR] = 28.1; 95% confidence interval [CI]= 7.4–107.0) and restlessness (OR = 16.0; 95% CI = 4.2–61.6) SAQ^© factors compared to non-fatigued, but not for factors of sleep apnea or excessive daytime somnolence. This is consistent with studies finding that, while fatigued, CFS subjects are not sleepy. A strong correlation (0.78) of Epworth score was found only for the excessive daytime somnolence factor.

Conclusions

SAQ^© factors describe sleep abnormalities associated with CFS and provide more information than the Epworth score. Validation of these promising results will require formal polysomnographic sleep studies.

     

Molecular analysis of the eighteen most frequent mutations in the BRCA1 gene in 63 Chilean breast cancer families

BRCA1 gene mutations account for nearly all families with multiple cases of both early onset breast and/or ovarian cancer and about 30% of hereditary breast cancer. Although to date more than 1,237 distinct mutations, polymorphisms, and variants have been described, several mutations have been found to be recurrent in this gene. We have analyzed 63 Chilean breast/ovarian cancer families for eighteen frequent BRCA1 mutations. The analysis of the five exons and two introns in which these mutations are located was made using mismatch PCR assay, ASO hybridization assay, restriction fragment analysis, allele specific PCR assay and direct sequentiation techniques. Two BRCA1 mutations (185delAG and C61G) and one variant of unknown significance (E1250K) were found in four of these families. Also, a new mutation (4185delCAAG) and one previously described polymorphism (E1038G) were found in two other families. The 185delAG was found in a 3.17% of the families and the others were present only in one of the families of this cohort. Therefore these mutations are not prominent in the Chilean population. The variant of unknown significance and the polymorphism detected could represent a founder effect of Spanish origin.     

Hepatitis B surface antigen immunopurification using a plant-derived specific antibody produced in large scale

This paper provides an evaluation of a plant-derived HBsAg-specific antibody in the immunopurification of the recombinant HBsAg for vaccine purposes. This plant-derived antibody was obtained from different batches of 100-200kg of tobacco leaves and coupled to Sepharose CL-4B with high efficiency. The plant-derived antibody immunoaffinity matrix purification behavior (elution capacity, antigen purity, purification cycles, and ligand leakage) was comparable to that of its mouse-derived monoclonal antibody homolog. This result supports the feasibility of using this plant-derived antibody for the immunopurification of the Hepatitis B surface antigen for human use, opening a new possibility to overcome the constrain of monoclonal antibody production in mice.     

Perinatal development of endothelial nitric oxide synthase-deficient mice

The purpose of this study was to evaluate the influence of endothelial nitric oxide synthase (eNOS) deficiency on fetal growth, perinatal survival, and limb development in a mouse model with a targeted mutagenesis of the Nos3 gene. Wild-type (Nos3+/+) and eNOS-deficient fetuses (Nos3-/-) were evaluated on Gestational Day (E)15 and E17, and newborn pups were observed on Day 1 of life (D1). The average term duration of pregnancy was 19 days. For the evaluation of postnatal development, a breeding scheme consisting of Nos3+/- x Nos3+/- and Nos3-/- x Nos3-/- mice was established, and offspring were observed for 3 wk. Southern blotting was used for genotyping. No significant differences in fetal weight, crown-rump lengths (CRL), and placental weight were seen between Nos3+/+ and Nos3-/- fetuses on E15. By E17, Nos3-/- fetuses showed significantly reduced fetal weights, CRL, and placental weights. This difference in body weight was also seen throughout the whole postnatal period. In pregnancies of Nos3-/- females, the average number of pups alive on D1 was significantly decreased compared to either E15 or E17. Placental histology revealed no abnormalities. On E15, E17, and D1, Nos3(-/-) fetuses demonstrated focal acute hemorrhages in the distal limbs in 0%, 2.6%, and 5.7%, respectively, of all mutant mice studied on the respective days. Bone measurements showed significantly shorter bones in the peripheral digits of hindpaws of Nos3-/- newborns. We conclude mice deficient for eNOS show characteristically abnormal prenatal and postnatal development including fetal growth restriction, reduced survival, and an increased rate of limb abnormalities. The development of this characteristic phenotype of eNOS-deficient mice dates back to the prenatal development during the late third trimester of pregnancy.     

Direct inhibition of the hexose transporter GLUT1 by tyrosine kinase inhibitors

The facilitative hexose transporter GLUT1 is a multifunctional protein that transports hexoses and dehydroascorbic acid, the oxidized form of vitamin C, and interacts with several molecules structurally unrelated to the transported substrates. Here we analyzed in detail the interaction of GLUT1 with a group of tyrosine kinase inhibitors that include natural products of the family of flavones and isoflavones and synthetic compounds such as the tyrphostins. These compounds inhibited, in a dose-dependent manner, the transport of hexoses and dehydroascorbic acid in human myeloid HL-60 cells, in transfected Chinese hamster ovary cells overexpressing GLUT1, and in normal human erythrocytes, and blocked the glucose-displaceable binding of cytochalasin B to GLUT1 in erythrocyte ghosts. Kinetic analysis of transport data indicated that only tyrosine kinase inhibitors with specificity for ATP binding sites inhibited the transport activity of GLUT1 in a competitive manner. In contrast, those inhibitors that are competitive with tyrosine but not with ATP failed to inhibit hexose uptake or did so in a noncompetitive manner. These results, together with recent evidence demonstrating that GLUT1 is a nucleotide binding protein, support the concept that the inhibitory effect on transport is related to the direct interaction of the inhibitors with GLUT1. We conclude that predicted nucleotide-binding motifs present in GLUT1 are important for the interaction of the tyrosine kinase inhibitors with the transporter and may participate directly in the binding transport of substrates by GLUT1.     

The C-terminal region of hPrp8 interacts with the conserved GU dinucleotide at the 5' splice site

A U5 snRNP protein, hPrp8, forms a UV-induced crosslink with the 5' splice site (5'SS) RNA within splicing complex B assembled in trans- as well as in cis-splicing reactions. Both yeast and human Prp8 interact with the 5'SS, branch site, polypyrimidine tract, and 3'SS during splicing. To begin to define functional domains in Prp8 we have mapped the site of the 5'SS crosslink within the hPrp8 protein. Immunoprecipitation analysis limited the site of crosslink to the C-terminal 5060-kDa segment of hPrp8. In addition, size comparison of the crosslink-containing peptides generated with different proteolytic reagents with the pattern of fragments predicted from the hPrp8 sequence allowed for mapping of the crosslink to a stretch of five amino acids in the C-terminal portion of hPrp8 (positions 1894-1898). The site of the 5'SS:hPrp8 crosslink falls within a segment spanning the previously defined polypyrimidine tract recognition domain in yPrp8, suggesting that an overlapping region of Prp8 may be involved both in the 5'SS and polypyrimidine tract recognition events. In the context of other known interactions of Prp8, these results suggest that this protein may participate in formation of the catalytic center of the spliceosome.