Longitudinal analysis of the vaginal microflora in pregnancy suggests that L. crispatus promotes the stability of the normal vaginal microflora and that L. gasseri and/or L. iners are more conducive to the occurrence of abnormal vaginal microflora

<p>Abstract</p> <p>Background</p> <p>Despite their antimicrobial potential, vaginal lactobacilli often fail to retain dominance, resulting in overgrowth of the vagina by other bacteria, as observed with bacterial vaginosis. It remains elusive however to what extent interindividual differences in vaginal <it>Lactobacillus </it>community composition determine the stability of this microflora. In a prospective cohort of pregnant women we studied the stability of the normal vaginal microflora (assessed on Gram stain) as a function of the presence of the vaginal <it>Lactobacillus </it>index species (determined through culture and molecular analysis with tRFLP).</p> <p>Results</p> <p>From 100 consecutive Caucasian women vaginal swabs were obtained at mean gestational ages of 8.6 (SD 1.4), 21.2 (SD 1.3), and 32.4 (SD 1.7) weeks, respectively. Based on Gram stain, 77 women had normal or <it>Lactobacillus</it>-dominated vaginal microflora (VMF) during the first trimester, of which 18 had grade Ia (<it>L. crispatus </it>cell morphotypes) VMF (23.4%), 16 grade Iab (<it>L. crispatus </it>and other <it>Lactobacillus </it>cell morphotypes) VMF (20.8%), and 43 grade Ib (non-<it>L. crispatus </it>cell morphotypes) VMF (55.8%). Thirteen women with normal VMF at baseline, converted in the second or third trimester (16.9%) to abnormal VMF defined as VMF dominated by non-<it>Lactobacillus </it>bacteria. Compared to grade Ia and grade Iab VMF, grade Ib VMF were 10 times (RR = 9.49, 95% CI 1.30 – 69.40) more likely to convert from normal to abnormal VMF (p = 0.009). This was explained by the observation that normal VMF comprising <it>L. gasseri/iners </it>incurred a ten-fold increased risk of conversion to abnormal VMF relative to non-<it>L. gasseri/iners </it>VMF (RR 10.41, 95% CI 1.39–78.12, p = 0.008), whereas normal VMF comprising <it>L. crispatus </it>had a five-fold decreased risk of conversion to abnormal VMF relative to non-<it>L. crispatus </it>VMF (RR 0.20, 95% CI 0.05–0.89, p = 0.04).</p> <p>Conclusion</p> <p>The presence of different <it>Lactobacillus </it>species with the normal vaginal microflora is a major determinant to the stability of this microflora in pregnancy: <it>L. crispatus </it>promotes the stability of the normal vaginal microflora while <it>L. gasseri </it>and/or <it>L. iners </it>predispose to some extent to the occurrence of abnormal vaginal microflora.</p

Comparative Risks of Initial Aortic Events Associated With Genetic Thoracic Aortic Disease

Pathogenic variant; Precision medicine; Thoracic aortic aneurysmVariante patógena; Medicina de precisión; Aneurisma de la aorta torácicaVariant patògena; Medicina de precisió; Aneurisma de l'aorta toràcicaBackground Pathogenic variants in 11 genes predispose individuals to heritable thoracic aortic disease (HTAD), but limited data are available to stratify the risk for aortic events associated with these genes. Objectives This study sought to compare the risk of first aortic event, specifically thoracic aortic aneurysm surgery or an aortic dissection, among 7 HTAD genes and variant types within each gene. Methods A retrospective cohort of probands and relatives with rare variants in 7 genes for HTAD (n = 1,028) was assessed for the risk of first aortic events based on the gene altered, pathogenic variant type, sex, proband status, and location of recruitment. Results Significant differences in aortic event risk were identified among the smooth muscle contraction genes (ACTA2, MYLK, and PRKG1; P = 0.002) and among the genes for Loeys-Dietz syndrome, which encode proteins in the transforming growth factor (TGF)-β pathway (SMAD3, TGFB2, TGFBR1, and TGFBR2; P < 0.0001). Cumulative incidence of type A aortic dissection was higher than elective aneurysm surgery in patients with variants in ACTA2, MYLK, PRKG1, and SMAD3; in contrast, patients with TGFBR2 variants had lower cumulative incidence of type A aortic dissection than elective aneurysm surgery. Cumulative incidence of type B aortic dissection was higher for ACTA2, PRKG1, and TGFBR2 than other genes. After adjusting for proband status, sex, and recruitment location, specific variants in ACTA2 and TGFBR2 were associated with substantially higher risk of aortic event with childhood onset. Conclusions Gene- and variant-specific data on aortic events in individuals with HTAD support personalized aortic surveillance and clinical management.These studies were funded by the National Institutes of Health (NIH) (NIH R01HL109942 to Dr Milewicz DMM and K23HL127266 to Dr Morris), Genetic Aortic Disorders Association Canada, Temerty Family Foundation, and the John Ritter Foundation. Dr LeMaire serves as a consultant for Terumo Aortic and Cerus; and serves as a principal investigator for clinical studies sponsored by Terumo Aortic and CytoSorbents. Dr Morris is on the scientific advisory board for vascular Ehlers Danlos syndrome clinical trial for Aytu Biopharma. Dr Regalado is an employee and shareholder of Invitae. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose

Let’s Team Up! Measuring Student Teachers’ Perceptions of Team Teaching Experiences

Since collaboration within schools gains importance and is considered significant for teachers’ professional development in order to meet the new 21st-century educational demands, teacher education institutes show a growing interest in field experiences inspired by collaborative learning, such as team teaching. Team teaching is a teaching model in which (student) teachers work collaboratively in the preparation, teaching and evaluation of a course. In order to assess team teaching practices in teacher education by monitoring perceptions of collaborative team teaching experiences, an instrument is needed that offers insights to guide the learning process and support well-founded decision making. Therefore, an easy-to-use quantitative questionnaire to explore student teachers’ team teaching perceptions was developed and validated in four stages: an extensive literature review (1) resulting in a preliminary questionnaire containing advantages and disadvantages of team teaching (2). Next, a pilot study was conducted with 14 student teachers (3), followed by a further validation and reliability study based on exploratory factor analysis, peer debriefing, confirmatory factor analysis and internal consistency analysis with 181 participating student teachers (4). The final questionnaire comprises 29 Likert-items in four scales – collaboration, co-creation, coaching and complexity – and appears to be both valid and reliable

Quantitative determination by real-time PCR of four vaginal Lactobacillus species, Gardnerella vaginalis and Atopobium vaginae indicates an inverse relationship between L. gasseri and L. iners

Background: Most studies of the vaginal microflora have been based on culture or on qualitative molecular techniques. Here we applied existing real-time PCR formats for Lactobacillus crispatus, L. gasseri and Gardnerella vaginalis and developed new formats for Atopobium vaginae, L. iners and L. jensenii to obtain a quantitative non culture-based determination of these species in 71 vaginal samples from 32 pregnant and 28 non-pregnant women aged between 18 and 45 years. Results: The 71 vaginal microflora samples of these women were categorized, using the Ison and Hay criteria, as refined by Verhelst et al. (2005), as follows: grade la: 8 samples, grade lab: 10, grade lb: 13, grade I-like: 10, grade II: 11, grade III: 12 and grade IV: 7. L. crispatus was found in all but 5 samples and was the most frequent Lactobacillus species detected. A significantly lower concentration of L. crispatus was found in grades II (p < 0.0001) and III (p = 0.002) compared to grade I. L. jensenii was found in all grades but showed higher concentration in grade lab than in grade la (p = 0.024). A. vaginae and G. vaginalis were present in high concentrations in grade III, with log(10) median concentrations (log(10) MC), respectively of 9.0 and 9.2 cells/ml. Twenty (38.5%) of the 52 G. vaginalis positive samples were also positive for A. vaginae. In grade II we found almost no L. iners (log(10) MC: 0/ml) but a high concentration of L. gasseri (log(10) MC: 8.7/ml). By contrast, in grade III we found a high concentration of L. iners (log(10) MC: 8.3/ml) and a low concentration of L. gasseri (log(10) MC: 0/ml). These results show a negative association between L. gasseri and L. iners (r = -0.397, p = 0.001) and between L. gasseri and A. vaginae (r = -0.408, p < 0.0001). Conclusion: In our study we found a clear negative association between L. iners and L. gasseri and between A. vaginae and L. gasseri. Our results do not provide support for the generally held proposition that grade II is an intermediate stage between grades I and III, because L. gasseri, abundant in grade II is not predominant in grade III, whereas L. iners, abundant in grade III is present only in low numbers in grade II samples

Modified classification of Gram-stained vaginal smears to predict spontaneous preterm birth : a prospective cohort study

In a prospective cohort study, we assessed the predictive value of a modified vaginal smear scoring method to identify risk for spontaneous preterm birth

Comparison between Gram stain and culture for the characterization of vaginal microflora: Definition of a distinct grade that resembles grade I microflora and revised categorization of grade I microflora

BACKGROUND: The microbiological diagnosis of bacterial vaginosis is usually made using Nugent's criteria, a useful but rather laborious scoring system based on counting bacterial cell types on Gram stained slides of vaginal smears. Ison and Hay have simplified the score system to three categories and added a fourth category for microflora with a predominance of the Streptococcus cell type. Because in the Nugent system several cell types are not taken into account for a final score, we carried out a detailed assessment of the composition of the vaginal microflora in relation to standard Gram stain in order the improve the diagnostic value of the Gram stain. To this purpose we compared Gram stain based categorization of vaginal smears with i) species specific PCR for the detection of Gardnerella vaginalis and Atopobium vaginae and with ii) tDNA-PCR for the identification of most cultivable species. RESULTS: A total of 515 samples were obtained from 197 pregnant women, of which 403 (78.3%) were categorized as grade I microflora, 46 (8.9%) as grade II, 22 (4.3%) as grade III and 8 (1.6%) as grade IV, according to the criteria of Ison and Hay. Another 36 samples (7.0%) were assigned to the new category 'grade I-like', because of the presence of diphtheroid bacilli cell types. We found that 52.7% of the grade I-like samples contained Bifidobacterium spp. while L. crispatus was present in only 2.8% of the samples and G. vaginalis and A. vaginae were virtually absent; in addition, the species diversity of this category was similar to that of grade II specimens. Based on the presence of different Lactobacillus cell types, grade I specimens were further characterized as grade Ia (40.2%), grade Iab (14.9%) and grade Ib (44.9%). We found that this classification was supported by the finding that L. crispatus was cultured from respectively 87.0% and 76.7% of grade Ia and Iab specimens while this species was present in only 13.3% of grade Ib specimens, a category in which L. gasseri and L. iners were predominant. CONCLUSION: Further refinement of Gram stain based grading of vaginal smears is possible by distinguishing additional classes within grade I smears (Ia, Iab and Ib) and by adding a separate category, designated grade I-like. A strong correlation was found between grade Ia and the presence of L. crispatus and between grade I-like and the presence of bifidobacteria. This refinement of Gram stain based scoring of vaginal smears may be helpful to improve the interpretation of the clinical data in future studies, such as the understanding of response to treatment and recurrence of bacterial vaginosis in some women, and the relationship between bacterial vaginosis and preterm birth

Microflora of the penile skin-lined neovagina of transsexual women

<p>Abstract</p> <p>Background</p> <p>The microflora of the penile skin-lined neovagina in male-to-female transsexuals is a recently created microbial niche which thus far has been characterized only to a very limited extent. Yet the knowledge of this microflora can be considered as essential to the follow-up of transsexual women. The primary objective of this study was to map the neo-vaginal microflora in a group of 50 transsexual women for whom a neovagina was constructed by means of the inverted penile skin flap technique. Secondary objectives were to describe possible correlations of this microflora with multiple patients' characteristics, such as sexual orientation, the incidence of vaginal irritation and malodorous vaginal discharge.</p> <p>Results</p> <p>Based on Gram stain the majority of smears revealed a mixed microflora that had some similarity with bacterial vaginosis (BV) microflora and that contained various amounts of cocci, polymorphous Gram-negative and Gram-positive rods, often with fusiform and comma-shaped rods, and sometimes even with spirochetes. <it>Candida </it>cells were not seen in any of the smears.</p> <p>On average 8.6 species were cultured per woman. The species most often found were: <it>Staphylococcus epidermidis</it>, <it>Streptococcus anginosus </it>group spp., <it>Enterococcus faecalis, Corynebacterium </it>sp., <it>Mobiluncus curtisii </it>and <it>Bacteroides ureolyticus</it>. Lactobacilli were found in only one of 30 women</p> <p>There was no correlation between dilatation habits, having coitus, rinsing habits and malodorous vaginal discharge on the one hand and the presence of a particular species on the other. There was however a highly significant correlation between the presence of <it>E. faecalis </it>on the one hand and sexual orientation and coitus on the other (p = 0.003 and p = 0.027 respectively).</p> <p>Respectively 82%, 58% and 30% of the samples showed an amplicon after amplification with <it>M. curtisii</it>, <it>Atopobium vaginae </it>and <it>Gardnerella vaginalis </it>primer sets.</p> <p>Conclusion</p> <p>Our study is the first to describe the microflora of the penile skin-lined neovagina of transsexual women. It reveals a mixed microflora of aerobe and anaerobe species usually found either on the skin, in the intestinal microflora or in a BV microflora.</p

Identification and genotyping of bacteria from paired vaginal and rectal samples from pregnant women indicates similarity between vaginal and rectal microflora

Background: The vaginal microflora is important for maintaining vaginal health and preventing infections of the reproductive tract. The rectum has been suggested as the major source for the colonisation of the vaginal econiche. Methods: To establish whether the rectum can serve as a possible bacterial reservoir for colonisation of the vaginal econiche, we cultured vaginal and rectal specimens from pregnant women at 35-37 weeks of gestation, identified the isolates to the species level with tRNA intergenic length polymorphism analysis (tDNA-PCR) and genotyped the isolates for those subjects from which the same species was isolated simultaneously vaginally and rectally, by RAPD-analysis. One vaginal and one rectal swab were collected from a total of each of 132 pregnant women at 35-37 weeks of gestation. Swabs were cultured on Columbia CNA agar and MRS agar. For each subject 4 colonies were selected for each of both sites, i.e. 8 colonies in total. Results: Among the 844 isolates that could be identified by tDNA-PCR, a total of 63 bacterial species were present, 9 (14%) only vaginally, 26 (41%) only rectally, and 28 (44%) in both vagina and rectum. A total of 121 (91.6%) of 132 vaginal samples and 51 (38.6%) of 132 rectal samples were positive for lactobacilli. L. crispatus was the most frequently isolated Lactobacillus species from the vagina (40% of the subjects were positive), followed by L. jensenii (32%), L. gasseri (30%) and L. iners (11%). L. gasseri was the most frequently isolated Lactobacillus species from the rectum (15%), followed by L. jensenii (12%), L. crispatus (11%) and L. iners (2%). A total of 47 pregnant women carried the same species vaginally and rectally. This resulted in 50 vaginal/rectal pairs of the same species, for a total of eight different species. For 34 of the 50 species pairs (68%), isolates with the same genotype were present vaginally and rectally and a high level of genotypic diversity within species per subject was also established. Conclusion: It can be concluded that there is a certain degree of correspondence between the vaginal and rectal microflora, not only with regard to species composition but also with regard to strain identity between vaginal and rectal isolates. These results support the hypothesis that the rectal microflora serves as a reservoir for colonisation of the vaginal econiche

Antibiotic susceptibility of Atopobium vaginae

BACKGROUND: Previous studies have indicated that a recently described anaerobic bacterium, Atopobium vaginae is associated with bacterial vaginosis (BV). Thus far the four isolates of this fastidious micro-organism were found to be highly resistant to metronidazole and susceptible for clindamycin, two antibiotics preferred for the treatment of BV. METHODS: Nine strains of Atopobium vaginae, four strains of Gardnerella vaginalis, two strains of Lactobacillus iners and one strain each of Bifidobacterium breve, B. longum, L. crispatus, L. gasseri and L. jensenii were tested against 15 antimicrobial agents using the Etest. RESULTS: All nine strains of A. vaginae were highly resistant to nalidixic acid and colistin while being inhibited by low concentrations of clindamycin (range: < 0.016 μg/ml), rifampicin (< 0.002 μg/ml), azithromycin (< 0.016 – 0.32 μg/ml), penicillin (0.008 – 0.25 μg/ml), ampicillin (< 0.016 – 0.94 μg/ml), ciprofloxacin (0.023 – 0.25 μg/ml) and linezolid (0.016 – 0.125 μg/ml). We found a variable susceptibility for metronidazole, ranging from 2 to more than 256 μg/ml. The four G. vaginalis strains were also susceptible for clindamycin (< 0.016 – 0.047 μg/ml) and three strains were susceptible to less than 1 μg/ml of metronidazole. All lactobacilli were resistant to metronidazole (> 256 μg/ml) but susceptible to clindamycin (0.023 – 0.125 μg/ml). CONCLUSION: Clindamycin has higher activity against G. vaginalis and A. vaginae than metronidazole, but not all A. vaginae isolates are metronidazole resistant, as seemed to be a straightforward conclusion from previous studies on a more limited number of strains

The contribution of a 9p21.3 variant, a KIF6 variant, and C-reactive protein to predicting risk of myocardial infarction in a prospective study

<p>Abstract</p> <p>Background</p> <p>Genetic risk factors might improve prediction of coronary events. Several variants at chromosome 9p21.3 have been widely reported to be associated with coronary heart disease (CHD) in prospective and case-control studies. A variant of <it>KIF6 </it>(719Arg) has also been reported to be associated with increased risk of CHD in large prospective studies, but not in case-control studies. We asked whether the addition of genetic information (the 9p21.3 or <it>KIF6 </it>variants) or a well-established non-genetic risk factor (C-reactive protein [CRP]) can improve risk prediction by the Framingham Risk Score (FRS) in the Cardiovascular Health Study (CHS)--a prospective observational study of risk factors for cardiovascular disease among > 5,000 participants aged 65 or older.</p> <p>Methods</p> <p>Improvement of risk prediction was assessed by change in the area under the receiver-operator characteristic curve (AUC) and by net reclassification improvement (NRI).</p> <p>Results</p> <p>Among white participants the FRS was improved by addition of <it>KIF6 </it>719Arg carrier status among men as assessed by the AUC (from 0.581 to 0.596, P = 0.03) but not by NRI (NRI = 0.027, P = 0.32). Adding both CRP and 719Arg carrier status to the FRS improved risk prediction by the AUC (0.608, P = 0.02) and NRI (0.093, P = 0.008) in men, but not women (P ≥ 0.24).</p> <p>Conclusions</p> <p>While none of these risk markers individually or in combination improved risk prediction among women, a combination of <it>KIF6 </it>719Arg carrier status and CRP levels modestly improved risk prediction among white men; although this improvement is not significant after multiple-testing correction. These observations should be investigated in other prospective studies.</p