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Junction Region (junction + region)
Selected AbstractsClaudin-5 is Restricted to the Tight Junction Region of Uterine Epithelial Cells in the Uterus of Pregnant/Gravid Squamate ReptilesTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2008Joanna M. Biazik Abstract Claudin-5, a tight junctional protein associated with ion and size selectivity, has been found in the uterus of skinks. This study has generated critical information about the molecular assembly of the tight junction at various stages of the reproductive cycle in the skink uterus. Recent studies looking at tight junctional proteins found occludin expression in the tight junction region of uterine epithelial cells in the skink uterus; however, occludin did not disclose any further information about the ions and size of ions permeating across the paracellular pathway. A ,22-kDa claudin-5 band was detected in the uterus of the skinks present in this study and immunohistochemistry revealed that claudin-5 redistributes to the tight junction region of the lateral plasma membrane of uterine epithelial cells in late stage pregnancy/gravidity. This finding indicates that the tight junction becomes more assembled to precisely regulate ion and solute permeation in late stage pregnancy/gravidity. Claudin-5 with its functional role as a molecular sieve due to the formation of ion and size selective pores suggests that permeation of ions smaller than 0.8 kDa are restricted when claudin-5 is redistributed to the tight junction region of the later plasma membrane. This report is the first description of the molecular mechanisms that may be involved in regulating nutrient provision in the reptilian uterus. Anat Rec, 291:547,556, 2008. © 2008 Wiley-Liss, Inc. [source] Genetic analysis of HAV strains recovered from patients with acute hepatitis from Southern ItalyJOURNAL OF MEDICAL VIROLOGY, Issue 3 2003Maria Chironna Abstract Southern Italy is an endemic area for HAV infection contributing to the majority of Italian hepatitis A cases. Using molecular analysis, HAV strains have been classified in distinct genotypes and subgenotypes. To characterize HAV wild-type strains circulating in Southern Italy, sequence analysis of VP3-VP1 and VP1/2A junction regions of HAV isolates recovered from 25 patients with acute hepatitis during 2000 and 2001 was carried out. HAV isolates showed a degree of identity, after pairwise comparison with one another, ranging from 91.9,100% in the VP3-VP1 junction region and 89.9,100% in the VP1/2A junction region. All strains belonged to genotype I, with 84% (21/25) of samples clustering in subgenotype IA and 16% (4/25) in subgenotype IB. Cocirculation of subgenotypes IA and IB was observed among isolates from 2000, whereas all strains from 2001 were subgenotype IA. In addition, the subgenotype IA strains formed different clusters, one of which was related closely to some Cuban strains, showing a percent similarity of 98.8% in the 168-base pair segment encompassing the VP1/2A junction and the same amino acid substitution. The latter finding suggests that this subgenotype variant circulates also in the Mediterranean area. The results of the phylogenetic analysis confirm the genetic heterogeneity among HAV strains in Western Europe. J. Med. Virol. 70:343,349, 2003. © 2003 Wiley-Liss, Inc. [source] Characterization of hepatitis A virus isolates from subgenotypes IA and IB in Rio de Janeiro, Brazil,JOURNAL OF MEDICAL VIROLOGY, Issue 1 2002Vanessa S. de Paula Abstract Hepatitis A virus (HAV) isolates from around the world have been classified into seven genotypes (I,VII). Most human strains belong to genotype I, which has been divided into two subgenotypes, A and B. South America has provided a small number of strains studied at the genome level. In the present study, IgM anti-HAV antibodies were detected in 116 out of 250 (46%) serum samples collected from consecutive patients with acute hepatitis referred to the Brazilian Reference Center for Viral Hepatitis, Rio de Janeiro. Viral RNA were extracted from all 250 samples and submitted to a reverse transcription-polymerase chain reaction (RT-PCR) assay designed to amplify a genome segment in the VP1/2A junction region. HAV RNA was detected in 54/116 (47%) and 17/134 (13%) IgM anti-HAV-positive and -negative sera, respectively. In addition, HAV RNA was detected in 17/35 (49%) IgM anti-HAV-positive sera that had been collected at a day care center where cases of acute hepatitis were being observed for 3 months. Nucleotide sequences (168 bp) of PCR products were determined for 30 HAV isolates. Phylogenetic analysis showed that 21 belonged to subgenotype IB, while 9 were of subgenotype IA. Interestingly, a concomitant circulation of isolates from subgenotypes IA and IB was observed in the day care center. J. Med. Virol. 66:22,27, 2002. © 2002 Wiley-Liss, Inc. [source] PRIMER NOTE: Primers for amplifying the hypervariable, male-transmitted COII-COI junction region in amblemine freshwater mussels (Bivalvia: Unionoidea: Ambleminae)MOLECULAR ECOLOGY RESOURCES, Issue 3 2007JENNIFER M. WALKER Abstract Freshwater bivalves in the superfamily Unionoidea possess distinct male (M)- and female (F)-transmitted mitochondrial DNA (mtDNA). The former evolves independently of and at a significantly faster rate than the latter. Thus, population genetic and phylogenetic analyses of M sequences facilitate the generation of independent estimates of genetic variation and evolutionary relationships which are often more robust than those provided by analyses of F sequences alone. However, M mtDNA's rapid substitution rate often renders polymerase chain reaction (PCR) amplification difficult with ,universal' primers. Herein, we report on three pairs of PCR primers that consistently amplify the hypervariable M COII-COI gene junction region in 25 bivalve genera (Unionoidea: Ambleminae). [source] Claudin-5 is Restricted to the Tight Junction Region of Uterine Epithelial Cells in the Uterus of Pregnant/Gravid Squamate ReptilesTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2008Joanna M. Biazik Abstract Claudin-5, a tight junctional protein associated with ion and size selectivity, has been found in the uterus of skinks. This study has generated critical information about the molecular assembly of the tight junction at various stages of the reproductive cycle in the skink uterus. Recent studies looking at tight junctional proteins found occludin expression in the tight junction region of uterine epithelial cells in the skink uterus; however, occludin did not disclose any further information about the ions and size of ions permeating across the paracellular pathway. A ,22-kDa claudin-5 band was detected in the uterus of the skinks present in this study and immunohistochemistry revealed that claudin-5 redistributes to the tight junction region of the lateral plasma membrane of uterine epithelial cells in late stage pregnancy/gravidity. This finding indicates that the tight junction becomes more assembled to precisely regulate ion and solute permeation in late stage pregnancy/gravidity. Claudin-5 with its functional role as a molecular sieve due to the formation of ion and size selective pores suggests that permeation of ions smaller than 0.8 kDa are restricted when claudin-5 is redistributed to the tight junction region of the later plasma membrane. This report is the first description of the molecular mechanisms that may be involved in regulating nutrient provision in the reptilian uterus. Anat Rec, 291:547,556, 2008. © 2008 Wiley-Liss, Inc. [source] Precise mapping of breakpoints in conserved synteny between human chromosome 1 and pig chromosomes 4, 6 and 9ANIMAL GENETICS, Issue 2 2002H. S. Sun Previous comparative mapping suggested that at least five pig chromosomes (Sscr4, 6, 9, 10 and 14) share homology with human chromosome 1 (Hsap1). A significant quantitative trait loci (QTL) for fat deposition has been identified on Sscr4 that appears to be near the junction region between Sscr4 and Sscr9 relative to Hsap1. It is of interest to define the boundaries of conserved synteny between pig chromosomes and Hsap1 to use human map information to identify putative comparative positional candidates for this QTL. Eleven genes, including Janus kinase 1 (JAK1), Prostaglandin E receptor3 (PTGER3), urate oxidase (UOX), coagulation factor 3 (F3), vascular cell adhesion molecule 1 (VCAM1), ribosomal protein L5 (RPL5), POU domain, class 2, transcription factor 1 (POU2F1), coagulation factor 5 (F5), Prostaglandin endoperoxide synthase-2 (PTGS2), myosin binding protein H (MYBPH) and Antithrombin III (SERPINC1), were selected to refine the boundaries of the blocks of conserved synteny between Hsap1 and pig chromosomes. Pig sequence tagged sites (STSs) were developed and used to physically map these 11 genes using a somatic cell hybrid panel. Eight loci have been mapped by using fluorescent in situ hybridization (FISH) to improve map resolution. Heterologous FISH was used to refine the location of VCAM1 on human chromosomes. In addition, human yeast artificial chromosomes (YACs) were mapped by heterologous FISH on pig metaphases to refine the boundaries of the regions of homology between Sscr4 and Sscr9 on Hsap1. Results from this study suggest the precise break in conserved synteny on Hsap1 corresponding to the Sscr4/6 and Sscr4/9 transitions are most likely on the Hsap1p22 and Hsap1q24,25 regions, respectively. Further, our data predict that Hsap1q21,24 is a candidate region for the backfat QTL localized to Sscr4. [source] Interactions between onshore bedrock-channel incision and nearshore wave-base erosion forced by eustasy and tectonicsBASIN RESEARCH, Issue 2 2002N.P. Snyder We explore the response of bedrock streams to eustatic and tectonically induced fluctuations in base level. A numerical model coupling onshore fluvial erosion with offshore wave-base erosion is developed. The results of a series of simulations for simple transgressions with constant rate of sea-level change (SLR) show that response depends on the relative rates of rock uplift (U) and wave-base erosion (,w). Simple regression runs highlight the importance of nearshore bathymetry. Shoreline position during sea-level fall is set by the relative rate of base-level fall (U-SLR) and ,w, and is constant horizontally when these two quantities are equal. The results of models forced by a realistic Late Quaternary sea-level curve are presented. These runs show that a stable shoreline position cannot be obtained if offshore uplift rates exceed ,w. Only in the presence of a relatively stable shoreline position, fluvial profiles can begin to approximate a steady-state condition, with U balanced by fluvial erosion rate (,f). In the presence of a rapid offshore decrease in rock-uplift rate (U), short (,5 km) fluvial channels respond to significant changes in rock-uplift rate in just a few eustatic cycles. The results of the model are compared to real stream-profile data from the Mendocino triple junction region of northern California. The late Holocene sea-level stillstand response exhibited by the simulated channels is similar to the low-gradient mouths seen in the California streams. [source] | ||||||||||