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21.
OBJECTIVE: To determine the yield of opportunistic Pap smears taken in an unscreened and medically underserved population in the Transkei Region of South Africa. STUDY DESIGN: Cross-sectional study of 22,160 cervical cytology specimens from an unscreened population attending gynecologic outpatient clinics between January 1990 and December 1996. RESULTS: The overall prevalence of atypical squamous cells of uncertain significance (ASCUS), low grade squamous intraepithelial lesions (LSIL) and high grade squamous intraepithelial lesions (HSIL) was, respectively, 34.7%, 8.3% and 2.4%. The ASCUS: SIL ratio was 3:1. The prevalence of invasive squamous cell carcinoma was 1.6%. The yield of opportunistic Pap smears was 10.7% including only LSIL and HSIL. CONCLUSION: The pathologic process of precursor lesions of cervical cancer appears to start at an early age since > 20% of cases are diagnosed before the age of 30 years. In the absence of a national screening program, opportunistic testing of medically underserved women needs to be maintained and encouraged. 相似文献
22.
Gutacker MM Smoot JC Migliaccio CA Ricklefs SM Hua S Cousins DV Graviss EA Shashkina E Kreiswirth BN Musser JM 《Genetics》2002,162(4):1533-1543
Several human pathogens (e.g., Bacillus anthracis, Yersinia pestis, Bordetella pertussis, Plasmodium falciparum, and Mycobacterium tuberculosis) have very restricted unselected allelic variation in structural genes, which hinders study of the genetic relationships among strains and strain-trait correlations. To address this problem in a representative pathogen, 432 M. tuberculosis complex strains from global sources were genotyped on the basis of 230 synonymous (silent) single nucleotide polymorphisms (sSNPs) identified by comparison of four genome sequences. Eight major clusters of related genotypes were identified in M. tuberculosis sensu stricto, including a single cluster representing organisms responsible for several large outbreaks in the United States and Asia. All M. tuberculosis sensu stricto isolates of previously unknown phylogenetic position could be rapidly and unambiguously assigned to one of the eight major clusters, thus providing a facile strategy for identifying organisms that are clonally related by descent. Common clones of M. tuberculosis sensu stricto and M. bovis are distinct, deeply branching genotypic complexes whose extant members did not emerge directly from one another in the recent past. sSNP genotyping rapidly delineates relationships among closely related strains of pathogenic microbes and allows construction of genetic frameworks for examining the distribution of biomedically relevant traits such as virulence, transmissibility, and host range. 相似文献
23.
24.
Su HP Brugnera E Van Criekinge W Smits E Hengartner M Bogaert T Ravichandran KS 《The Journal of biological chemistry》2000,275(13):9542-9549
Phagocytosis of apoptotic cells is a key step in the completion of programmed cell death that occurs throughout life in multicellular organisms. The molecular events involved in clearance of apoptotic cells are just beginning to be elucidated. Recently, CED-6, an adapter protein involved in engulfment has been cloned in Caenorhabditis elegans and in humans. CED-6 is composed of a phosphotyrosine-binding (PTB) domain and a proline-rich C-terminal domain with no apparent catalytic domain. Since PTB domains, originally identified in Shc, mediate intracellular signaling downstream of cell surface receptors, CED-6 has also been proposed to mediate intracellular signals leading to engulfment. In this report, we demonstrate that CED-6 dimerizes through a leucine zipper domain that is immediately adjacent to the PTB domain. Several lines of evidence based on co-immunoprecipitation studies, yeast two-hybrid assays, and gel filtration studies suggest that CED-6 exists as a dimer in vivo. Through mutational analyses, we show that the leucine zipper is necessary and sufficient for CED-6 dimerization and that this dimerization is conserved among C. elegans, rodent, and human CED-6 proteins. We propose that dimerization may have unique implications for ligand binding via CED-6 and its function during the phagocytosis of apoptotic cells. 相似文献
25.
Jean-Fran?ois Bastin Adeline Fayolle Yegor Tarelkin Jan Van den Bulcke Thales de Haulleville Frederic Mortier Hans Beeckman Joris Van Acker Adeline Serckx Jan Bogaert Charles De Cannière 《PloS one》2015,10(11)
Context
Wood specific gravity is a key element in tropical forest ecology. It integrates many aspects of tree mechanical properties and functioning and is an important predictor of tree biomass. Wood specific gravity varies widely among and within species and also within individual trees. Notably, contrasted patterns of radial variation of wood specific gravity have been demonstrated and related to regeneration guilds (light demanding vs. shade-bearing). However, although being repeatedly invoked as a potential source of error when estimating the biomass of trees, both intraspecific and radial variations remain little studied. In this study we characterized detailed pith-to-bark wood specific gravity profiles among contrasted species prominently contributing to the biomass of the forest, i.e., the dominant species, and we quantified the consequences of such variations on the biomass.Methods
Radial profiles of wood density at 8% moisture content were compiled for 14 dominant species in the Democratic Republic of Congo, adapting a unique 3D X-ray scanning technique at very high spatial resolution on core samples. Mean wood density estimates were validated by water displacement measurements. Wood density profiles were converted to wood specific gravity and linear mixed models were used to decompose the radial variance. Potential errors in biomass estimation were assessed by comparing the biomass estimated from the wood specific gravity measured from pith-to-bark profiles, from global repositories, and from partial information (outer wood or inner wood).Results
Wood specific gravity profiles from pith-to-bark presented positive, neutral and negative trends. Positive trends mainly characterized light-demanding species, increasing up to 1.8 g.cm-3 per meter for Piptadeniastrum africanum, and negative trends characterized shade-bearing species, decreasing up to 1 g.cm-3 per meter for Strombosia pustulata. The linear mixed model showed the greater part of wood specific gravity variance was explained by species only (45%) followed by a redundant part between species and regeneration guilds (36%). Despite substantial variation in wood specific gravity profiles among species and regeneration guilds, we found that values from the outer wood were strongly correlated to values from the whole profile, without any significant bias. In addition, we found that wood specific gravity from the DRYAD global repository may strongly differ depending on the species (up to 40% for Dialium pachyphyllum).Main Conclusion
Therefore, when estimating forest biomass in specific sites, we recommend the systematic collection of outer wood samples on dominant species. This should prevent the main errors in biomass estimations resulting from wood specific gravity and allow for the collection of new information to explore the intraspecific variation of mechanical properties of trees. 相似文献26.
I. N. A. Van Bogaert S. Roelants D. Develter W. Soetaert 《Biotechnology letters》2010,32(10):1509-1514
Sophorolipids production by the yeast Candia bombicola is most favourable when glucose is used as a carbon source in combination with a hydrophobic carbon source such as a common
vegetable oil. Most vegetable oils are comprised of C16–C18 fatty acids, an ideal range for sophorolipid production. The use
of oils with either shorter or longer fatty acids, such has coconut oil or meadowfoam oil, respectively, was evaluated. Such
oils did not contribute to enhanced sophorolipid production when compared to cultures run on glucose as the sole carbon source.
Moreover, a toxic effect of medium-chain fatty acids towards stationary C. bombicola cells was demonstrated. 相似文献
27.
Martine E. Laethem Frans M. Belpaire Pascal Wijnant Marie-Thrse Rosseel Marc G. Bogaert 《Chirality》1994,6(5):405-410
The influence of endotoxin-induced inflammation on the enantioselective pharmacokinetics of propranolol, oxprenolol, and verapamil, which bind to α1-acid glycoprotein, was studied in the rat. The racemic mixtures were given orally. In the control animals, for propranolol and oxprenolol, the plasma concentrations of the (R)-enantiomer were higher than those of the (S)-enantiomer, while for verapamil the reverse was true. Protein binding and intrinsic clearance are the main factors responsible for this enantioselectivity. After endotoxin treatment, for the three drugs tested the plasma concentrations and the plasma binding of both enantiomers were significantly increased. This effect was more pronounced for (R)-propranolol, (R)-oxprenolol, and (S)-verapamil than for their respective antipodes. The enantioselective effect of endotoxin on the plasma concentrations of the drugs studied seems mainly due to the enantioselective increase in binding to α1-acid glycoprotein. © 1994 Wiley-Liss, Inc. 相似文献
28.
Van Bogaert IN Saerens K De Muynck C Develter D Soetaert W Vandamme EJ 《Applied microbiology and biotechnology》2007,76(1):23-34
Sophorolipids are surface-active compounds synthesized by a selected number of yeast species. They have been known for over
40 years, but because of growing environmental awareness, they recently regained attention as biosurfactants due to their
biodegradability, low ecotoxicity, and production based on renewable resources. In this paper, an overview is given of the
producing yeast strains and various aspects of fermentative sophorolipid production. Also, the biochemical pathways and regulatory
mechanisms involved in sophorolipid biosynthesis are outlined. To conclude, a summary is given on possible applications of
sophorolipids, either as native or modified molecules. 相似文献
29.
Azizieh R Orduz D Van Bogaert P Bouschet T Rodriguez W Schiffmann SN Pirson I Abramowicz MJ 《Molecular neurobiology》2011,44(1):111-121
The potassium channel tetramerization domain-containing protein 7 (KCTD7) was named after the structural homology of its predicted
N-terminal broad complex, tramtrack and bric à brac/poxvirus and zinc finger domain with the T1 domain of the Kv potassium
channel, but its expression profile and cellular function are still largely unknown. We have recently reported a homozygous
nonsense mutation of KCTD7 in patients with a novel form of autosomal recessive progressive myoclonic epilepsy. Here, we show that KCTD7 expression
hyperpolarizes the cell membrane and reduces the excitability of transfected neurons in patch clamp experiments. We found
the expression of KCTD7 in the hippocampal and Purkinje cells of the murine brain, an expression profile consistent with our
patients’ phenotype. The effect on the plasma membrane resting potential is possibly mediated by Cullin-3, as we demonstrated
direct molecular interaction of KCTD7 with Cullin-3 in co-immunoprecipitation assays. Our data link progressive myoclonic
epilepsy to an inherited defect of the neuron plasma membrane’s resting potential in the brain. 相似文献