24 research outputs found
Biological Earth observation with animal sensors
Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmen-tal change
High Diversity and Variability in the Vaginal Microbiome in Women following Preterm Premature Rupture of Membranes (PPROM): A Prospective Cohort Study.
To characterize the vaginal microbiota of women following preterm premature rupture of membranes (PPROM), and determine if microbiome composition predicts latency duration and perinatal outcomes.A prospective cohort study.Canada.Women with PPROM between 24+0 and 33+6 weeks gestational age (GA).Microbiome profiles, based on pyrosequencing of the cpn60 universal target, were generated from vaginal samples at time of presentation with PPROM, weekly thereafter, and at delivery.Vaginal microbiome composition, latency duration, gestational age at delivery, perinatal outcomes.Microbiome profiles were generated from 70 samples from 36 women. Mean GA at PPROM was 28.8 wk (mean latency 2.7 wk). Microbiome profiles were highly diverse but sequences representing Megasphaera type 1 and Prevotella spp. were detected in all vaginal samples. Only 13/70 samples were dominated by Lactobacillus spp. Microbiome profiles at the time of membrane rupture did not cluster by gestational age at PPROM, latency duration, presence of chorioamnionitis or by infant outcomes. Mycoplasma and/or Ureaplasma were detected by PCR in 81% (29/36) of women, and these women had significantly lower GA at delivery and correspondingly lower birth weight infants than Mycoplasma and/or Ureaplasma negative women.Women with PPROM had mixed, abnormal vaginal microbiota but the microbiome profile at PPROM did not correlate with latency duration. Prevotella spp. and Megasphaera type I were ubiquitous. The presence of Mollicutes in the vaginal microbiome was associated with lower GA at delivery. The microbiome was remarkably unstable during the latency period
GA at PPROM, latency duration and delivery mode for 36 women enrolled in the study.
<p>GA ranges corresponding to extremely (<28 weeks), very (28 to <32 weeks) or moderately (32 to <34 weeks) preterm are indicated by grey shading.</p
Summary of PPROM to delivery timelines.
<p>Summary of PPROM to delivery timelines.</p
Average linkage hierarchical clustering of <i>cpn</i>60 based microbiome profiles of T<sub>0</sub> vaginal samples from 24 women.
<p>Nearest neighbour species representing at least 10% of the microbiome of at least one woman are included.</p
Proportional latency (A), absolute latency (B), GA at birth (C) and infant birthweight (D) for women with Mollicutes PCR positive or negative T<sub>0</sub> vaginal samples.
<p>Distributions were compared using a Mann-Whitney U test with <i>P</i> <0.05 considered significant.</p
Vaginal microbiome profiles over the post-PPROM latency period.
<p>Data is presented as proportion of the total sequence reads obtained for each sample, with the height of the ordinate corresponding to 100%. Sampling times are indicated with vertical broken lines, and collection time (weeks) for each sample is indicated on the abscissa. Samples indicated as collected at "0+" were collected within 3 days following PPROM, but were post-antibiotic treatment. Sample identification numbers appear in the upper left corner of each panel. The legend includes nearest neighbour species that account for at least 10% of the sequence reads in at least one sample. All women received one or more broad-spectrum antibiotics including Ampicillin, Erythromycin, Amoxicillin, Metronidazole, Clindamycin, Cefazolin, Nitrofurantoin, and/or Penicillin G.</p
16S rRNA gene sequence and phylogenetic tree of lactobacillus species from the vagina of healthy Nigerian women
Background: The vaginal microbial community plays a vital role in maintaining women\u27s health. Understanding the precise bacterial composition is challenging because of the diverse and difficult-to-culture nature of many bacterial constituents, necessitating culture-independent methodology. During a natural menstrual cycle, physiological changes could have an impact on bacterial growth, colonization, and community structure. The objective of this study was to assess the stability of the vaginal microbiome of healthy Canadian women throughout a menstrual cycle by using cpn60-based microbiota analysis. Vaginal swabs from 27 naturally cycling reproductive-age women were collected weekly through a single menstrual cycle. Polymerase chain reaction (PCR) was performed to amplify the universal target region of the cpn60 gene and generate amplicons representative of the microbial community. Amplicons were pyrosequenced, assembled into operational taxonomic units, and analyzed. Samples were also assayed for total 16S rRNA gene content and Gardnerella vaginalis by quantitative PCR and screened for the presence of Mollicutes by using family and genus-specific PCR.Results: Overall, the vaginal microbiome of most women remained relatively stable throughout the menstrual cycle, with little variation in diversity and only modest fluctuations in species richness. Microbiomes between women were more different than were those collected consecutively from individual women. Clustering of microbial profiles revealed the expected groupings dominated by Lactobacillus crispatus, Lactobacillus iners, and Lactobacillus jensenii. Interestingly, two additional clusters were dominated by either Bifidobacterium breve or a heterogeneous mixture of nonlactobacilli. Direct G. vaginalis quantification correlated strongly with its pyrosequencing-read abundance, and Mollicutes, including Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum, were detected in most samples.Conclusions: Our cpn60-based investigation of the vaginal microbiome demonstrated that in healthy women most vaginal microbiomes remained stable through their menstrual cycle. Of interest in these findings was the presence of Bifidobacteriales beyond just Gardnerella species. Bifidobacteriales are frequently underrepresented in 16S rRNA gene-based studies, and their detection by cpn60-based investigation suggests that their significance in the vaginal community may be underappreciated
Characterization of the vaginal microbiota of healthy Canadian women through the menstrual cycle
BACKGROUND: The vaginal microbial community plays a vital role in maintaining women\u2019s health. Understanding the
precise bacterial composition is challenging because of the diverse and difficult-to-culture nature of many bacterial
constituents, necessitating culture-independent methodology. During a natural menstrual cycle, physiological
changes could have an impact on bacterial growth, colonization, and community structure. The objective of this
study was to assess the stability of the vaginal microbiome of healthy Canadian women throughout a menstrual
cycle by using cpn60-based microbiota analysis. Vaginal swabs from 27 naturally cycling reproductive-age women
were collected weekly through a single menstrual cycle. Polymerase chain reaction (PCR) was performed to amplify
the universal target region of the cpn60 gene and generate amplicons representative of the microbial community.
Amplicons were pyrosequenced, assembled into operational taxonomic units, and analyzed. Samples were also
assayed for total 16S rRNA gene content and Gardnerella vaginalis by quantitative PCR and screened for the
presence of Mollicutes by using family and genus-specific PCR.
RESULTS: Overall, the vaginal microbiome of most women remained relatively stable throughout the menstrual
cycle, with little variation in diversity and only modest fluctuations in species richness. Microbiomes between
women were more different than were those collected consecutively from individual women. Clustering of
microbial profiles revealed the expected groupings dominated by Lactobacillus crispatus, Lactobacillus iners,
and Lactobacillus jensenii. Interestingly, two additional clusters were dominated by either Bifidobacterium breve
or a heterogeneous mixture of nonlactobacilli. Direct G. vaginalis quantification correlated strongly with its
pyrosequencing-read abundance, and Mollicutes, including Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma
urealyticum, were detected in most samples.
CONCLUSIONS: Our cpn60-based investigation of the vaginal microbiome demonstrated that in healthy women
most vaginal microbiomes remained stable through their menstrual cycle. Of interest in these findings was the
presence of Bifidobacteriales beyond just Gardnerella species. Bifidobacteriales are frequently underrepresented
in 16S rRNA gene-based studies, and their detection by cpn60-based investigation suggests that their significance in the
vaginal community may be underappreciated.Peer reviewed: YesNRC publication: Ye
Evidence of Subclinical mtDNA Alterations in HIV-Infected Pregnant Women Receiving Combination Antiretroviral Therapy Compared to HIV-Negative Pregnant Women.
Combination antiretroviral therapy (cART) can effectively prevent vertical transmission of HIV but there is potential risk of adverse maternal, foetal or infant effects. Specifically, the effect of cART use during pregnancy on mitochondrial DNA (mtDNA) content in HIV-positive (HIV+) women is unclear. We sought to characterize subclinical alterations in peripheral blood mtDNA levels in cART-treated HIV+ women during pregnancy and the postpartum period.This prospective longitudinal observational cohort study enrolled both HIV+ and HIV-negative (HIV-) pregnant women. Clinical data and blood samples were collected at three time points in pregnancy (13-<23 weeks, 23-<30 weeks, 30-40 weeks), and at delivery and six weeks post-partum in HIV+ women. Peripheral blood mtDNA to nuclear DNA (nDNA) ratio was measured by qPCR.Over a four year period, 63 HIV+ and 42 HIV- women were enrolled. HIV+ women showed significantly lower mtDNA/nDNA ratios compared to HIV- women during pregnancy (p = 0.003), after controlling for platelet count and repeated measurements using a multivariable mixed-effects model. Ethnicity, gestational age (GA) and substance use were also significantly associated with mtDNA/nDNA ratio (p≤0.02). Among HIV+ women, higher CD4 nadir was associated with higher mtDNA/nDNA ratios (p<0.0001), and these ratio were significantly lower during pregnancy compared to the postpartum period (p<0.0001).In the context of this study, it was not possible to distinguish between mtDNA effects related to HIV infection versus cART therapy. Nevertheless, while mtDNA levels were relatively stable over time in both groups during pregnancy, they were significantly lower in HIV+ women compared to HIV- women. Although no immediate clinical impact was observed on maternal or infant health, lower maternal mtDNA levels may exert long-term effects on women and children and remain a concern. Improved knowledge of such subclinical alterations is another step toward optimizing the safety and efficacy of cART regimens during pregnancy