109 research outputs found
Dermal substitutes for fullâthickness wounds in a oneâstage grafting model
We tested different biodegradable matrix materials as dermal substitutes in a porcine wound model. Matrixes were covered with a split-skin mesh graft and protected with a microporous, semipermeable membrane, which prevents blister formation, wound infection and provides ultimate healing conditions. Evaluation parameters were as follows: epithelization, dermal reconstitution, wound contraction, and cosmetic and functional aspect. A microfibrillar matrix of nondenatured collagen gave the best result, with immediate fibroblast ingrowth and epidermal outgrowth. Slight inflammatory reaction and minimal wound contraction were observed. Application of a split-skin mesh graft, in combination with this collagen matrix, generated a thicker dermal layer than did a split-skin mesh graft directly applied on a wound bed. However, the histologic dermal architecture was less optimal than one obtained with a full-thickness punch graft method. Other matrixes caused inflammatory reactions, interfering with epithelization and dermal reconstitution. We conclude that a nondenatured collagen matrix, in combination with a split-skin mesh graft, can provide a substitute dermis in a full-thickness wound. This combination is preferable to a split-skin mesh graft directly applied on the wound bed. With our microporous semipermeable membrane, the combined use of a dermal substitute and a split-skin mesh graft can be applied in a single-stage operatio
Genetic variation in the MBL2 gene is associated with Chlamydia trachomatis infection and host humoral response to Chlamydia trachomatis infection
This study aims to assess the potential association of MBL2 gene single nucleotide polymorphisms (SNPs) to Chlamydia trachomatis infection. We analysed a selected sample of 492 DNA
and serum specimens from Dutch Caucasian women. Women were categorized into four groups of
infection status based on the results of DNA and antibody tests for C. trachomatis: Ct-DNA+/IgG+, CtDNA+/IgGâ, Ct-DNAâ/IgG+, and Ct-DNAâ/IgGâ. We compared six MBL2 SNPs (â619G > C (H/L),
â290G > C (Y/X), â66C > T (P/Q), +154C > T (A/D), +161A > G (A/B), and +170A > G (A/C)) and
their respective haplotypes in relation to these different subgroups. The â619C (L) allele was less
present within the Ct-DNAâ/IgG+ group compared with the Ct-DNAâ/IgGâ group (OR = 0.49;
95% CI: 0.28â0.83), while the +170G (C) allele was observed more in the Ct-DNA+/IgG+ group as
compared with the Ct-DNAâ/IgGâ group (OR = 2.4; 95% CI: 1.1â5.4). The HYA/HYA haplotype
was more often present in the Ct-DNAâ/IgGâ group compared with the Ct-DNA+/IgG+ group
(OR = 0.37; 95% CI: 0.16â0.87). The +170G (C) allele was associated with increased IgG production
(p = 0.048) in C. trachomatis PCR-positive women. This study shows associations for MBL in immune
reactions to C. trachomatis. We showed clear associations between MBL2 genotypes, haplotypes, and
individualsâ stages of C. trachomatis DNA and IgG positivity.NGI Life Sciences Pre-Seed and a EuroTransBio grant.https://www.mdpi.com/journal/ijerphMedical Microbiolog
Slow Epidemic of Lymphogranuloma Venereum L2b Strain
We traced the Chlamydia trachomatis L2b variant in Amsterdam and San Francisco. All recent lymphogranuloma venereum cases in Amsterdam were caused by the L2b variant. This variant was also present in the 1980s in San Francisco. Thus, the current "outbreak" is most likely a slowly evolving epidemic
Typing of Lymphogranuloma Venereum Chlamydia trachomatis Strains
We analyzed by multilocus sequence typing 77 lymphogranuloma venereum Chlamydia trachomatis strains from men who have sex with men in Europe and the United States. Specimens from an outbreak in 2003 in Europe were monoclonal. In contrast, several strains were in the United States in the 1980s, including a variant from Europe
Molecular assessment of bacterial vaginosis by Lactobacillus abundance and species diversity
__Background:__ To date, women are most often diagnosed with bacterial vaginosis (BV) using microscopy based Nugent scoring or Amsel criteria. However, the accuracy is less than optimal. The aim of the present study was to confirm the identity of known BV-associated composition profiles and evaluate indicators for BV using three molecular methods.
__Methods:__ Evaluation of indicators for BV was carried out by 16S rRNA amplicon sequencing of the V5-V7 region, a tailor-made 16S rRNA oligonucleotide-based microarray, and a PCR-based profiling technique termed IS-profiling, which is based on fragment variability of the 16S-23S rRNA intergenic spacer region. An inventory of vaginal bacterial species was obtained from 40 females attending a Dutch sexually transmitted infection outpatient clinic, of which 20 diagnosed with BV (Nugent score 7-10), and 20 BV negative (Nugent score 0-3).
__Results:__ Analysis of the bacterial communities by 16S rRNA amplicon sequencing revealed two clusters in the BV negative women, dominated by either Lactobacillus iners or Lactobacillus crispatus and three distinct clusters in the BV positive women. In the former, there was a virtually complete, negative correlation between L. crispatus and L. iners. BV positive subjects showed cluster profiles that were relatively high in bacterial species diversity and dominated by anaerobic species, including Gardnerella vaginalis, an
Can previous associations of single nucleotide polymorphisms in the tlr2, nod1, cxcr5, and il10 genes in the susceptibility to and severity of chlamydia trachomatis infections be confirmed?
Clear inter-individual differences exist in the response to C. trachomatis (CT) infections and reproductive tract complications in women. Host genetic variation like single nucleotide polymorphisms (SNPs) have been associated with differences in response to CT infection, and SNPsmight be used as a genetic component in a tubal-pathology predicting algorithm. Our aimwas to confirmthe role of four genes by investigating proven associated SNPs in the susceptibility and severity of a CT infection. A total of 1201 women fromfive cohorts were genotyped and analyzed for TLR2+2477 G>A, NOD1+32656 TâGG, CXCR5+10950 T>C, and IL10-1082 A>G. Results confirmed that NOD1+32656 TâGG was associated with an increased risk of a symptomatic CT infection (OR: 1.9, 95%CI: 1.1-3.4, p = 0.02), but we did not observe an association with late complications. IL10-1082 A>G appeared to increase the risk of late complications (i.e., ectopic pregnancy/tubal factor infertility) following a CT infection (OR=2.8, 95%CI: 1.1-7.1, p=0.02). Other associations were not found. Confirmatory studies are important, and large cohorts are warranted to further investigate SNPsâ role in the susceptibility and severity of a CT infection
Secondary metabolite profiling, growth profiles and other tools for species recognition and important Aspergillus mycotoxins
Species in the genus Aspergillus have been classified primarily
based on morphological features. Sequencing of house-hold genes has also been
used in Aspergillus taxonomy and phylogeny, while extrolites and
physiological features have been used less frequently. Three independent ways
of classifying and identifying aspergilli appear to be applicable: Morphology
combined with physiology and nutritional features, secondary metabolite
profiling and DNA sequencing. These three ways of identifying
Aspergillus species often point to the same species. This consensus
approach can be used initially, but if consensus is achieved it is recommended
to combine at least two of these independent ways of characterising aspergilli
in a polyphasic taxonomy. The chemical combination of secondary metabolites
and DNA sequence features has not been explored in taxonomy yet, however.
Examples of these different taxonomic approaches will be given for
Aspergillus section Nigri
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