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11.
G. E. Matt P. J. E. Quintana S. Liles M. F. Hovell J. M. Zakarian P. Jacob Iii 《Biomarkers》2013,18(6):507-523
AbstractThe utility of urinary trans-3′-hydroxy cotinine (3HC) as a biomarker of environmental tobacco smoke (ETS) exposure was investigated in comparison with urinary cotinine (COT), the sum (3HC?+?COT), and ratio of the two nicotine metabolites (3HC/COT). Participants were 150 ETS exposed children (aged 1–44 months) and their parents. Child urine samples were collected during 3weekly baseline assessments and at interviews administered 3, 6, 12, and 18 months after baseline. Findings indicate that 3HC and COT can be measured reliably (rho?=?0.96, 0.88) and show equivalent levels of repeated measures stability (rho?=?0.71, 0.75). COT, 3HC, and 3HC?+?COT showed equally strong associations with air nicotine levels, reported ETS contamination, and reported ETS exposure (r=0.60–0.70). The intraclass correlations of 3HC/COT were lower than those for COT or 3HC. Older children had a higher 3HC/COT ratio than younger children (3.5 versus 2.2), and non-Hispanic White children had a higher ratio than African-American children (3.2 versus 1.9). These findings suggest that COT, 3HC, and 3HC?+?COT are approximately equivalent and equally strong biomarkers of ETS exposure in children. Moreover, 3HC/COT may provide a useful indicator to investigate age- and race-related differences in the metabolism of COT and 3HC. 相似文献
12.
Andrea Gómez Bravo María Gabriela Quintana Marcelo Abril Oscar Daniel Salomón 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1071-1073
In 2004, the urban presence of Lutzomyia longipalpis was recorded
for the first time in Formosa province. In 2006, the first autochthonous case of
human urban visceral leishmaniasis (VL) was recorded in Misiones in the presence of
the vector, along with some canine VL cases. After this first case, the vector began
to spread primarily in northeast Argentina. Between 2008-2011, three human VL cases
were reported in Salta province, but the presence of Lu. longipalpis
was not recorded. Captures of Phlebotominae were made in Tartagal, Salta, in 2013,
and the presence of Lu. longipalpis was first recorded in northwest
Argentina at that time. Systematic sampling is recommended to observe the
distribution and dispersion patterns of Lu. longipalpis and consider
the risk of VL transmission in the region. 相似文献
13.
Hung-Chun Yu Jennifer L. Sloan Gunter Scharer Alison Brebner Anita M. Quintana Nathan P. Achilly Irini Manoli Curtis R. Coughlin II Elizabeth A. Geiger Una Schneck David Watkins Terttu Suormala Johan L.K. Van Hove Brian Fowler Matthias R. Baumgartner David S. Rosenblatt Charles P. Venditti Tamim H. Shaikh 《American journal of human genetics》2013
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To examine the relationship between gene conversion and reciprocal exchange at an endogenous chromosomal locus, we developed a reversion assay in a thymidine kinase deficient mutant, TX545, derived from the human lymphoblastoid cell line TK6. Selectable revertants of TX545 can be generated through interchromosomal gene conversion at the site of inactivating mutations on each tk allele or by reciprocal exchange that alters the linkage relationships of inactivating polymorphisms within the tk locus. Analysis of loss of heterozygosity (LOH) at intragenic polymorphisms and flanking microsatellite markers was used to initially evaluate allelotypes in TK(+) revertants for patterns associated with either gene conversion or crossing over. The linkage pattern in a subset of convertants was then unambiguously established, even in the event of prereplicative recombinational exchanges, by haplotype analysis of flanking microsatellite loci in tk(-/-) LOH mutants collected from the tk(+/-) parental convertant. Some (7/38; 18%) revertants were attributable to easily discriminated nonrecombinational mechanisms, including suppressor mutations within the tk coding sequence. However, all revertants classified as a recombinational event (28/38; 74%) were attributed to localized gene conversion, representing a highly significant preference (P < 0.0001) over gene conversion with associated reciprocal exchange, which was never observed. 相似文献
17.
Uva P Clément JL Austin JW Aubert J Zaffagnini V Quintana A Bagnères AG 《Molecular phylogenetics and evolution》2004,30(2):344-353
The Holoarctic termite genus Reticulitermes is widely distributed in Europe. A new Reticulitermes species, R. sp. nov, was recently found in France and Italy. Its phylogenetic position was investigated using a 743-bp fragment of mitochondrial 16S rRNA-ND1 genes and 382-bp of the nuclear ITS2 region. Phylogenies for these sequences were estimated by neighbor-joining, maximum-parsimony and maximum-likelihood analysis. The results strongly supported a relationship between R. sp. nov. and the termite species from the eastern Mediterranean area including Reticulitermes balkanensis from the Balkans, Reticulitermes lucifugus from Turkey and Reticulitermes clypeatus from Israel. The hypothesis of a relationship between R. sp. nov. and the Japanese Reticulitermes speratus was rejected by parametric bootstrap. The current distribution of R. sp. nov. could be linked to postglacial colonization routes between Balkan refuge and northern regions. 相似文献
18.
Hastings RH Quintana RA Sandoval R Burton DW Deftos LJ 《American journal of physiology. Lung cellular and molecular physiology》2003,285(6):L1312-L1322
Acute silica lung injury is marked by alveolar phospholipidosis and type II cell proliferation. Parathyroid hormone-related protein (PTHrP) 1-34 could have a regulatory role in this process because it stimulates phosphatidylcholine secretion and inhibits type II cell growth. Other regions of the PTHrP molecule may have biological activity and can also exert pulmonary effects. This study examined the temporal pattern for expression of several regions of PTHrP after silica lung injury and evaluated the effects of changes in expression on cell proliferation and lung phospholipids. Expression of all PTHrP regions fell at 4 days after injury. Reversing the decline in PTHrP 1-34 or PTHrP 67-86 with one intratracheal dose and four daily subcutaneous doses of PTHrP 1-34 or PTHrP 67-86 stimulated bronchoalveolar lavage disaturated phosphatidylcholine (DSPC) levels. Cell culture studies indicate that the peptides exerted direct effects on DSPC secretion by type II cells. Neither peptide affected type II cell proliferation with this dosing regimen, but addition of an additional intratracheal dose resulted in significant inhibition of growth, consistent with previous effects of PTHrP 1-34 in hyperoxic lung injury. These studies establish a regulatory role for PTHrP 1-34 and PTHrP 67-86 in DSPC metabolism and type II cell proliferation in silica injury. Growth inhibitory effects of PTHrP could interact with phospholipid stimulation by affecting type II cell numbers. Further studies are needed to explore the complex interactions of PTHrP-derived peptides and the type II cell response at various stages of silica lung injury. 相似文献
19.
Sosa J Llanes R Guzmán D Quintana I Flores M Gutiérrez O 《Memórias do Instituto Oswaldo Cruz》2001,96(4):523-525
The susceptibility to penicillin of 111 Neisseria meningitidis strains was assessed by the agar-dilution procedure and serosubtypes were determined by a whole-cell enzyme-linked immunoassay using monoclonal antibodies reagents. Thirty-five isolates showed reduced sensitivity to penicillin (MIC > or = 0.1 mg/l and < or = 1 mg/l) and no resistant strains were detected. The most common phenotype was B:4:P1.15 (77.5%) and a rising trend of non-typeable and non-subtypeable strains was detected. The increase in levels of minimal inhibitory concentrations of meningococci to penicillin gives cause for concern and the increase in non-typeable and non-subtypeable isolation demand the use of molecular biology techniques for their typing. 相似文献
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