Arianne Y. K. Albert

Characterization of the vaginal microbiota of healthy Canadian women through the menstrual cycle

BackgroundThe vaginal microbial community plays a vital role in maintaining women’s 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 cpn 60-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 cpn 60 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.ResultsOverall, 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.ConclusionsOur cpn 60-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 cpn 60-based investigation suggests that their significance in the vaginal community may be underappreciated.

Characterization of the upper respiratory tract microbiomes of patients with pandemic H1N1 influenza.

The upper respiratory tract microbiome has an important role in respiratory health. Influenza A is a common viral infection that challenges that health, and a well-recognized sequela is bacterial pneumonia. Given this connection, we sought to characterize the upper respiratory tract microbiota of individuals suffering from the pandemic H1N1 influenza A outbreak of 2009 and determine if microbiome profiles could be correlated with patient characteristics. We determined the microbial profiles of 65 samples from H1N1 patients by cpn60 universal target amplification and sequencing. Profiles were examined at the phylum and nearest neighbor “species” levels using the characteristics of patient gender, age, originating health authority, sample type and designation (STAT/non-STAT). At the phylum level, Actinobacteria-, Firmicutes- and Proteobacteria-dominated microbiomes were observed, with none of the patient characteristics showing significant profile composition differences. At the nearest neighbor “species” level, the upper respiratory tract microbiomes were composed of 13-20 “species” and showed a trend towards increasing diversity with patient age. Interestingly, at an individual level, most patients had one to three organisms dominant in their microbiota. A limited number of discrete microbiome profiles were observed, shared among influenza patients regardless of patient status variables. To assess the validity of analyses derived from sequence read abundance, several bacterial species were quantified by quantitative PCR and compared to the abundance of cpn60 sequence read counts obtained in the study. A strong positive correlation between read abundance and absolute bacterial quantification was observed. This study represents the first examination of the upper respiratory tract microbiome using a target other than the 16S rRNA gene and to our knowledge, the first thorough examination of this microbiome during a viral infection.

Cognitive and language outcomes in HIV-uninfected infants exposed to combined antiretroviral therapy in utero and through extended breast-feeding.

Objective:To determine whether there is a higher risk for cognitive or language delay among HIV-exposed uninfected (HEU) children exposed to cART (zidovudine/lamivudine/lopinavir/ritonavir) in utero and through 1 year of breast-feeding (World health Organization Option B+), compared with the control children born to HIV-uninfected mothers. Design:This is a double cohort study from Lusaka, Zambia. Methods:HEU (n = 97) and control (n = 103) children aged 15–36 months were assessed on their early nonverbal problem-solving and language skills using the standardized Capute Scales. A score of less than 85 on the Capute Full-Scale Developmental Quotient (FSDQ) was considered indicative of developmental delay and was the primary outcome of interest. Results:An FSDQ of less than 85 was found in eight (8.3%) of HEU participants and 15 (14.6%) of controls. In univariate logistic regressions, lower income [odds ratio (OR) = 0.93, P = 0.02], older infant age (OR = 1.08, P = 0.03), lower birth weight (OR = 0.16, P < 0.001), and less maternal education (OR = 0.41, P = 0.047) were associated with the probability of FSDQ less than 85, whereas Group (control/HEU) was not (OR = 1.88, P = 0.16). In the multivariable analysis, only lower birth weight (OR = 0.15, P < 0.001) remained associated with FSDQ less than 85. Conclusions:Our study did not support the presence of an adverse effect on cognitive and language development with prolonged antepartum and postpartum cART e/xposure. Larger studies and studies of older HEU children will be required to confirm these reassuring findings.

High Diversity and Variability in the Vaginal Microbiome in Women following Preterm Premature Rupture of Membranes (PPROM): A Prospective Cohort Study

Objective 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. Design A prospective cohort study Setting Canada Population Women with PPROM between 24+0 and 33+6 weeks gestational age (GA). Methods 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. Main Outcome Measures Vaginal microbiome composition, latency duration, gestational age at delivery, perinatal outcomes. Results 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. Conclusion 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.

Premature Spinal Bone Loss in Women Living with HIV is Associated with Shorter Leukocyte Telomere Length

With advances in combination antiretroviral therapy (cART), people living with HIV are now surviving to experience aging. Evidence suggests that individuals living with HIV are at greater risk for low bone mineral density (BMD), osteoporosis, and fractures. Better understanding of the pathophysiology of bone health in women living with HIV (WLWH) is important for treatment strategies. The goal of this study was to explore new biological factors linked to low BMD in WLWH. Standardized BMD measures of WLWH were compared to reference values from an unselected population of women from the same geographical region of the same age range. Linear regression analysis was used to assess relationships among health-related characteristics, cellular aging (measured by leukocyte telomere length; LTL), cART, and BMD of WLWH. WLWH (n = 73; mean age 43 ± 9 years) had lower BMD Z-scores at the lumbar spine (LS) (mean difference = −0.39, p < 0.001) and total hip (TH) (−0.29, p = 0.012) relative to controls (n = 290). WLWH between 50 and 60 years (n = 17) had lower Z-scores at the LS (p = 0.008) and TH (p = 0.027) compared to controls (n = 167). Among WLWH, LS BMD was significantly associated with LTL (R2 = 0.09, p = 0.009) and BMI (R2 = 0.06, p = 0.042). Spinal BMD was adversely affected in WLWH. Reduction of LTL was strongly associated with lower BMD and may relate to its pathophysiology and premature aging in WLWH.

Do protease inhibitor-containing combination antiretroviral therapy regimens increase risk of spontaneous preterm birth in pregnant HIV-Positive women?

administration with a meal or soft foods, and the impact of high doses of secnidazole on cardiac safety. SYM-1219 was administered in either applesauce, yogurt, or pudding, followed by 240 mL of water. Serial blood samples were collected to determine secnidazole plasma concentrations and PK parameters for each treatment group are reported. Safety assessments, ECGs, and vital signs were performed during each study. An in vitro metabolism program, including CYP metabolism, inhibition, and induction, substrate and inhibition potential for transporters, and the potential for secnidazole to inhibit ethanol metabolism was performed. RESULTS: A single 2-g oral dose of SYM-1219 achieves an average maximum plasma secnidazole concentration (Cmax) of 35.7 to 46.3 mg/mL approximately 2 to 3 hours after dosing (Tmax). Exposure, as assessed by area under the plasma-concentration time curve (AUC), increases linearly with dose. Secnidazole has a prolonged terminal elimination half-life (t1/2) of w17 hours. SYM-1219 can be administered in applesauce, pudding, or yogurt and the timing and content of a meal does not have an impact on drug bioavailability. Secnidazole is not a substrate or inhibitor of transporters nor does it induce or inhibit hepatic CYP450 enzymes, therefore the potential for clinically important interactions with CYP450 substrates, inhibitors, or inducers is minimal. In a clinical study, secnidazole had negligible impact on the PK of ethinyl estradiol or norethindrone, suggesting that a single dose of SYM-1219 will not impact the efficacy of oral contraceptives. Secnidazole does not inhibit aldehyde dehydrogenase in vitro and therefore does not alter ethanol metabolism. There were no clinically significant abnormalities in laboratory, vital signs, or ECGs following administration of SYM-1219 to study subjects. CONCLUSIONS: The favorable safety and efficacy profile of SYM-1219, coupled with its PK characteristics, are the foundation for this single-dose oral treatment regimen for BV.

Endocrine abnormalities in HIV‐infected women are associated with peak viral load ‐ the Children and Women: AntiRetrovirals and Markers of Aging (CARMA) Cohort

To investigate the prevalence of endocrine disturbances in a group of HIV‐positive (HIV+) women and to identify factors affecting presence of these disorders. To examine specifically whether cellular ageing, as measured by leukocyte telomere length (LTL), is correlated with the presence of endocrine disturbance.

Evidence of Subclinical mtDNA Alterations in HIV-Infected Pregnant Women Receiving Combination Antiretroviral Therapy Compared to HIV-Negative Pregnant Women

Introduction 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. Methods 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. Results 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). Conclusions 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.