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1.
Endemic pemphigus foliaceus (EPF) is a complex autoimmune disease characterized by the presence of antibodies against desmoglein 1, which lead to the loss of adhesion among keratinocytes (acantholysis). Variants of HLA class II genes have been the only genetic factors found to modulate susceptibility to EPF. This study aims at investigating the influence of cytokine genetic variants in the pathogenesis of EPF, since they may affect the expression levels of these immunomodulatory molecules. The sample included 168 patients and 189 controls and was comprised of mostly Caucasoids and Mulattos. The approach consisted of a case-control association study and the alleles were identified by mismatched PCR-RFLP. No associations were found with variants of IL1A, IL1B, IL1RN, IL4R and IL10. There was a weak negative association with the haplotype -1082G -592C (OR=0.49) of the IL10 gene in Mulattos. In regard to polymorphism -590 of the IL4 gene, a positive association with the T/T genotype (OR=2.71) and a negative association with the C variant (OR=0.37) were found. Associations with IL6 -174 variants suggest that the C/C genotype has a protective effect (OR=0.13) while carriers of the G allele are more susceptible (OR=7.66) to EPF.  相似文献   
2.
The prevalence of Mycobacterium bovis and other mycobacterial species in livestock specimens and milk was evaluated. An emphasis was placed upon the distribution of these organisms in milk that is readily available to the public that was either untreated, pasteurized, or treated using ultra high temperature. Twenty-two pathologic specimens from livestock (bovine, swine and bubaline) in five Brazilian states and 128 bovine milk samples from retail markets in the State of S o Paulo were examined for mycobacteria. Identification was made by classical biochemical tests, thin layer chromatography of mycolic acids and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Mycobacteria were isolated from 15 (68.2%) caseous lesions and from 23 (18%) milk samples. Eleven isolates were identified as M. bovis, and the remaining 27 nontuberculous mycobacterial isolates were represented by five species and six unidentified rapidly growing mycobacterial strains. The data demonstrate that animal products in Brazil are frequent reservoirs of mycobacteria and may pose a risk to the public.  相似文献   
3.
The genus Hisonotus was resurrected as a member of the tribe Otothyrini (actually subfamily Otothyrinae). However, phylogenetic studies based on morphological and molecular data showed that Hisonotus is not monophyletic and independent lineages can be identified, such as the group composed of the species Hisonotus insperatus, Hisonotus luteofrenatus, Hisonotus oliveirai, Hisonotus paresi and Hisonotus piracanjuba, a lineage unrelated to that containing the type species of the genus Hisonotus (Hisonotus notatus). Herein, based in molecular and morphological data, a new genus is described to accommodate the lineage mentioned above, into which are also added three new species. This new genus can be distinguished from other genera of Otothyrinae by the following combination of characters: (1) a pair of rostral plates at the tip of the snout; (2) two large pre-nasal plates just posterior to the rostral plates; (3) a supra-opercular plate that receives the laterosensory canal from the compound pterotic before the preopercle; (4) a well developed membrane at anal opening in females; and (5) a V-shaped spinelet. A key to species of Curculionichthys is provided.  相似文献   
4.

Background  

Parathyroid hormone (PTH) and PTH-related peptide (PTHrP) belong to a family of endocrine factors that share a highly conserved N-terminal region (amino acids 1-34) and play key roles in calcium homeostasis, bone formation and skeletal development. Recently, PTH-like peptide (PTH-L) was identified in teleost fish raising questions about the evolution of these proteins. Although PTH and PTHrP have been intensively studied in mammals their function in other vertebrates is poorly documented. Amphibians and birds occupy unique phylogenetic positions, the former at the transition of aquatic to terrestrial life and the latter at the transition to homeothermy. Moreover, both organisms have characteristics indicative of a complex system in calcium regulation. This study investigated PTH family evolution in vertebrates with special emphasis on Xenopus and chicken.  相似文献   
5.
A recent expedition to headwaters of the Rio Pandeiros, a left‐bank tributary of the Rio São Francisco revealed the presence of a fourth species of Hisonotus from that basin. Hisonotus devidei sp. nov. differs from congeners by the presence of conspicuous dark blotches of distinct shapes irregularly arranged along lateral and dorsal surfaces of the body and scattered throughout all fins, by possessing small plates in lateral portions of the abdomen and adjacent areas between pelvic fins without development of dermal plates and by morphometric ratios. The putative phylogenetic placement of the new species is discussed based on morphological comparisons with species of related Hypoptopomatinae genera and the Hisonotus species diversity within the Rio São Francisco Basin is compared with that of adjacent basins.  相似文献   
6.
Two new species of Pseudancistrus, a genus diagnosed by non-evertible cheek plates and hypertrophied odontodes along the snout margin, are described from two drainages of the Brazilian Shield: Pseudancistrus kayabi from the rio Teles Pires (rio Tapajós basin) and Pseudancistrus asurini from the rio Xingu. The new species are distinguished from congeners (Pseudancistrus barbatus, Pseudancistrus corantijniensis, Pseudancistrus depressus, Pseudancistrus nigrescens, Pseudancistrus reus, and Pseudancistrus zawadzkii) by the coloration pattern. Pseudancistrus kayabi has dark bars on the dorsal and caudal fins which are similar to that of Pseudancistrus reus from the Caroní River, Venezuela. Pseudancistrus asurini is unique among Pseudancistrus in having whitish tips of the dorsal and caudal fins in juveniles to medium-sized adults.  相似文献   
7.
8.
A561E, a novel cystic fibrosis (CF) associated mutation in the first nucleotide binding domain of CFTR, is the second most common CF mutation in Portugal. Properties of the A561E-CFTR protein were studied by immunoblotting, pulse-chase, immunocytochemistry, and MQAE halide-efflux assay in stably transfected BHK cells. Altogether, results presented here suggest that A561E causes protein mislocalization in the endoplasmic reticulum where the mutant protein must be trapped by the quality control mechanism. We conclude that A561E originates a protein trafficking defect, thus belonging to class II of CFTR mutations. As it is the case for F508del-CFTR (the most common CF mutant), low temperature treatment partially rescues a functional A561E-CFTR channel, suggesting that substitution of glutamic acid for alanine at position 561 does not completely abolish CFTR function. Pharmacological strategies previously reported for treatment of CF patients with the F508del mutation could thus be also effective in CF patients bearing the A561E mutation.  相似文献   
9.

Background  

Although direct infiltration of papillary carcinoma of thyroid to larynx, trachea and esophagus is well recognized, lymphatic and vascular metastases to larynx and hypopharynx have rarely been reported.  相似文献   
10.
The genus Rineloricaria is a Neotropical freshwater fish group with a long and problematic taxonomic history, attributed to the large number of species and the pronounced similarity among them. In the present work, taxonomic information and different molecular approaches were used to identify species boundaries and characterize independent evolutionary units. We analyzed 228 samples assembled in 53 distinct morphospecies. A general mixed yule-coalescent (GMYC) analysis indicated the existence of 70 entities, while BOLD system analyses showed the existence of 56 distinct BINs. When we used a new proposed integrative taxonomy approach, mixing the results obtained by each analysis, we identified 73 OTUs. We suggest that Rineloricaria probably has some complexity in the known species and several species not formally described yet. Our data suggested that other hyperdiverse fish groups with wide distributions can be further split into many new evolutionary taxonomic units.  相似文献   
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