Obstetrics and Gynaecology - Research Publications
Now showing items 1-12 of 326
Human Placental Mesenchymal Stem Cells (pMSCs) Play a Role as Immune Suppressive Cells by Shifting Macrophage Differentiation from Inflammatory M1 to Anti-inflammatory M2 Macrophages
(HUMANA PRESS INC, 2013-10-01)
BACKGROUND: Mesenchymal stem cells (MSCs) have a therapeutic potential in tissue repair because of capacity for multipotent differentiation and their ability to modulate the immune response. In this study, we examined the ability of human placental MSCs (pMSCs) to modify the differentiation of human monocytes into macrophages and assessed the influence of pMSCs on important macrophage functions. METHODS: We used GM-CSF to stimulate the differentiation of monocytes into the M1 macrophage pathway and then co-cultured these cells with pMSCs in the early stages of macrophage differentiation. We then evaluated the effect on differentiation by microscopic examination and by quantification of molecules important in the differentiation and immune functions of macrophages using flow cytometry and ELISA. The mechanism by which pMSCs could mediate their effects on macrophage differentiation was also studied. RESULTS: The co-culture of pMSCs with monocytes stimulated to follow the inflammatory M1 macrophage differentiation pathway resulted in a shift to anti-inflammatory M2-like macrophage differentiation. This transition was characterized by morphological of changes typical of M2 macrophages, and by changes in cell surface marker expression including CD14, CD36, CD163, CD204, CD206, B7-H4 and CD11b, which are distinctive of M2 macrophages. Co-culture with pMSCs reduced the expression of the costimulatory molecules (CD40, CD80 and CD86) and increased the expression of co-inhibitory molecules (CD273, CD274 and B7-H4) as well as the surface expression of major histocompatibility complex (MHC-II) molecules. Furthermore, the secretion of IL-10 was increased while the secretion of IL-1β, IL-12 (p70) and MIP-1α was decreased; a profile typical of M2 macrophages. Finally, pMSCs induced the phagocytic activity and the phagocytosis of apoptotic cells associated with M2- like macrophages; again a profile typical of M2 macrophages. We found that the immunoregulatory effect of pMSCs on macrophage differentiation was mediated by soluble molecules acting partially via glucocorticoid and progesterone receptors. CONCLUSIONS: We have shown that pMSCs can transition macrophages from an inflammatory M1 into an anti-inflammatory M2 phenotype. Our findings suggest a new immunosuppressive property of pMSCs that may be employed in the resolution of inflammation associated with inflammatory diseases and in tissue repair.
Differential Gene Expression in Menstrual Endometrium From Women With Self-Reported Heavy Menstrual Bleeding
(SAGE PUBLICATIONS INC, 2017-01-01)
Heavy menstrual bleeding (HMB) is a significant social and public health issue for menstruating women. Development of targeted treatments has been limited by poor understanding of local mechanisms underlying HMB. We aimed to determine how gene expression differs in menstrual phase endometrium from women with HMB. Menstrual phase endometrial biopsies were collected from women with (n = 7) and without (n = 10) HMB (regular menstrual cycles, no known pelvic pathology), as well as women with uterine fibroids (n = 7, n = 4 had HMB). Biopsies were analyzed using Illumina Sentrix Human HT12 arrays and data analyzed using "Remove Unwanted Variation-inverse". Ingenuity Pathway Analysis and the Database for Annotation, Visualization and Integrated Discovery v6.7 were used to identify gene pathways, functional gene clusters, and upstream regulators specific to the clinical groupings. Individual genes of interest were examined using quantitative polymerase chain reaction. In total, 829 genes were differentially expressed in one or more comparisons. Significant canonical pathways and gene clusters enriched in controls relative to both HMB and fibroid groups suggest the mechanisms responsible for HMB include modifications of the endometrial inflammatory or infection response. In contrast, differentially expressed genes in women with fibroids suggest modifications of hemoglobin, antigen processing, and the major histocompatibility complex (class II, beta chain) activity. In conclusion, HMB associated with fibroids may be regulated by different endometrial mechanisms from HMB in women without fibroids and from normal menstrual bleeding. These novel data provide numerous testable hypotheses that will advance our understanding of the mechanisms responsible for HMB.
CX-5461 activates the DNA damage response and demonstrates therapeutic efficacy in high-grade serous ovarian cancer
(NATURE PUBLISHING GROUP, 2020-05-26)
Acquired resistance to PARP inhibitors (PARPi) is a major challenge for the clinical management of high grade serous ovarian cancer (HGSOC). Here, we demonstrate CX-5461, the first-in-class inhibitor of RNA polymerase I transcription of ribosomal RNA genes (rDNA), induces replication stress and activates the DNA damage response. CX-5461 co-operates with PARPi in exacerbating replication stress and enhances therapeutic efficacy against homologous recombination (HR) DNA repair-deficient HGSOC-patient-derived xenograft (PDX) in vivo. We demonstrate CX-5461 has a different sensitivity spectrum to PARPi involving MRE11-dependent degradation of replication forks. Importantly, CX-5461 exhibits in vivo single agent efficacy in a HGSOC-PDX with reduced sensitivity to PARPi by overcoming replication fork protection. Further, we identify CX-5461-sensitivity gene expression signatures in primary and relapsed HGSOC. We propose CX-5461 is a promising therapy in combination with PARPi in HR-deficient HGSOC and also as a single agent for the treatment of relapsed disease.
Imputation techniques on missing values in breast cancer treatment and fertility data.
(BioMed Central, 2019-12-01)
Clinical decision support using data mining techniques offers more intelligent way to reduce the decision error in the last few years. However, clinical datasets often suffer from high missingness, which adversely impacts the quality of modelling if handled improperly. Imputing missing values provides an opportunity to resolve the issue. Conventional imputation methods adopt simple statistical analysis, such as mean imputation or discarding missing cases, which have many limitations and thus degrade the performance of learning. This study examines a series of machine learning based imputation methods and suggests an efficient approach to in preparing a good quality breast cancer (BC) dataset, to find the relationship between BC treatment and chemotherapy-related amenorrhoea, where the performance is evaluated with the accuracy of the prediction. To this end, the reliability and robustness of six well-known imputation methods are evaluated. Our results show that imputation leads to a significant boost in the classification performance compared to the model prediction based on listwise deletion. Furthermore, the results reveal that most methods gain strong robustness and discriminant power even the dataset experiences high missing rate (> 50%).
Screening circulating proteins to identify biomarkers of fetal macrosomia.
(BioMed Central, 2019-09-18)
OBJECTIVE: Fetal macrosomia is a major risk factor for shoulder dystocia, which can lead to birth asphyxia, maternal and neonatal traumatic injuries, and perinatal death. If macrosomia is diagnosed in the antenatal period, labour can be induced to decrease shoulder dystocia. But current clinical methods to diagnose fetal macrosomia antenatally perform with poor accuracy. Therefore, improved methods to accurately diagnose fetal macrosomia are required. Blood biomarkers that predict fetal macrosomia could be one such novel diagnostic strategy. We undertook a nested case-control study from a prospective collection of 1000 blood samples collected at 36 weeks' gestation. We analysed plasma samples from 52 women who subsequently delivered a macrosomic (> 95th centile for gestational age) infant and 106 controls. Circulating concentrations of the proteins COBLL1, CSH1, HSD3B1, EGFL6, XAGE3, S100P, PAPPA-1, ERBB2 were assessed for their ability to predict macrosomic infants. RESULTS: We did not identify any significant changes in the plasma concentrations of COBLL1, CSH1, HSD3B1, EGFL6, XAGE3, S100P, PAPPA-1, ERBB2 from women who subsequently delivered macrosomic neonates relative to control samples. Although we have not identified any potential biomarkers of fetal macrosomia, we have ruled out these particular eight protein candidates.
Azithromycin Versus Doxycycline for the Treatment of Genital Chlamydia Infection: A Meta-analysis of Randomized Controlled Trials
(OXFORD UNIV PRESS INC, 2014-07-15)
BACKGROUND: There has been recent debate questioning the efficacy of azithromycin for the treatment of urogenital chlamydia infection. We conducted a meta-analysis to compare the efficacy of 1 g azithromycin with 100 mg doxycycline twice daily (7 days) for the treatment of urogenital chlamydia infection. METHODS: Medline, PubMed, Embase, Cochrane Controlled Trials Register, Cochrane reviews, and Cumulative Index to Nursing and Allied Health Literature were searched until 31 December 2013. Randomized controlled trials comparing azithromycin with doxycycline for the treatment of genital chlamydia with evaluation of microbiological cure within 3 months of treatment were included. Sex, diagnostic test, follow-up time, attrition, patient symptomatic status, and microbiological cure were extracted. The primary outcome was the difference in efficacy at final follow-up. Study bias was quantitatively and qualitatively summarized. RESULTS: Twenty-three studies were included evaluating 1147 and 912 patients for azithromycin and doxycycline, respectively. We found a pooled efficacy difference in favor of doxycycline of 1.5% (95% confidence interval [CI], -.1% to 3.1%; I(2) = 1.9%; P = .435; random effects) to 2.6% (95% CI, .5%-4.7%; fixed effects). Subgroup analyses showed that the fixed effects pooled efficacy difference for symptomatic men was 7.4% (95% CI, 2.0%-12.9%), and the random effects was 5.5% (95% CI, -1.4% to 12.4%). CONCLUSIONS: There may be a small increased efficacy of up to 3% for doxycycline compared with azithromycin for the treatment of urogenital chlamydia and about 7% increased efficacy for doxycycline for the treatment of symptomatic urethral infection in men. However, the quality of the evidence varies considerably, with few double-blind placebo-controlled trials conducted. Given increasing concern about potential azithromycin failure, further well-designed and statistically powered double-blind, placebo-controlled trials are needed.
Treatment of rectal chlamydia infection may be more complicated than we originally thought
(OXFORD UNIV PRESS, 2015-04-01)
Rectal chlamydia diagnoses have been increasing among MSM and may also rise among women as anal sex rates increase among heterosexuals. However, there is growing concern about treatment for rectal chlamydia with treatment failures of up to 22% being reported. This article addresses factors that may be contributing to treatment failure for rectal chlamydia, including the pharmacokinetic properties of azithromycin and doxycycline in rectal tissue, the ability of chlamydia to transform into a persistent state that is less responsive to antimicrobial therapy, the impact of the rectal microbiome on chlamydia, heterotypic resistance, failure to detect cases of lymphogranuloma venereum and the performance of screening tests. If we are to reduce the burden of genital chlamydia, treatment for rectal chlamydia must be efficacious. This highlights the need for randomized controlled trial evidence comparing azithromycin with doxycycline for the treatment of rectal chlamydia.
The efficacy of azithromycin and doxycycline for the treatment of rectal chlamydia infection: a systematic review and meta-analysis
(OXFORD UNIV PRESS, 2015-05-01)
BACKGROUND: There are increasing concerns about treatment failure following treatment for rectal chlamydia with 1 g of azithromycin. A systematic review and meta-analysis was conducted to investigate the efficacy of 1 g of azithromycin as a single dose or 100 mg of doxycycline twice daily for 7 days for the treatment of rectal chlamydia. METHODS: Medline, Embase, PubMed, Cochrane Controlled Trials Register, Australia New Zealand Clinical Trial Register and ClinicalTrials.gov were searched to the end of April 2014. Studies using 1 g of azithromycin or 7 days of doxycycline for the treatment of rectal chlamydia were eligible. Gender, diagnostic test, serovar, symptomatic status, other sexually transmitted infections, follow-up time, attrition and microbial cure were extracted. Meta-analysis was used to calculate pooled (i) azithromycin and doxycycline efficacy and (ii) efficacy difference. RESULTS: All eight included studies were observational. The random-effects pooled efficacy for azithromycin (based on eight studies) was 82.9% (95% CI 76.0%-89.8%; I(2) = 71.0%; P < 0.01) and for doxycycline (based on five studies) was 99.6% (95% CI 98.6%-100%; I(2) = 0%; P = 0.571), resulting in a random-effects pooled efficacy difference (based on five studies) of 19.9% (95% CI 11.4%-28.3%; I(2) = 48.5%; P = 0.101) in favour of doxycycline. CONCLUSIONS: The efficacy of single-dose azithromycin may be considerably lower than 1 week of doxycycline for treating rectal chlamydia. However, the available evidence is very poor. Robust randomized controlled trials are urgently required.
Higher organism load associated with failure of azithromycin to treat rectal chlamydia
(CAMBRIDGE UNIV PRESS, 2016-09-01)
Repeat rectal chlamydia infection is common in men who have sex with men (MSM) following treatment with 1 g azithromycin. This study describes the association between organism load and repeat rectal chlamydia infection, genovar distribution, and efficacy of azithromycin in asymptomatic MSM. Stored rectal chlamydia-positive samples from MSM were analysed for organism load and genotyped to assist differentiation between reinfection and treatment failure. Included men had follow-up tests within 100 days of index infection. Lymphogranuloma venereum and proctitis diagnosed symptomatically were excluded. Factors associated with repeat infection, treatment failure and reinfection were investigated. In total, 227 MSM were included - 64 with repeat infections [28·2%, 95% confidence interval (CI) 22·4-34·5]. Repeat positivity was associated with increased pre-treatment organism load [odds ratio (OR) 1·7, 95% CI 1·4-2·2]. Of 64 repeat infections, 29 (12·8%, 95% CI 8·7-17·8) were treatment failures and 35 (15·4%, 95% CI 11·0-20·8) were reinfections, 11 (17·2%, 95% CI 8·9-28·7) of which were definite reinfections. Treatment failure and reinfection were both associated with increased load (OR 2·0, 95% CI 1·4-2·7 and 1·6, 95% CI 1·2-2·2, respectively). The most prevalent genovars were G, D and J. Treatment efficacy for 1 g azithromycin was 83·6% (95% CI 77·2-88·8). Repeat positivity was associated with high pre-treatment organism load. Randomized controlled trials are urgently needed to evaluate azithromycin's efficacy and whether extended doses can overcome rectal infections with high organism load.
A snapshot of Chlamydia trachomatis genetic diversity using multilocus sequence type analysis in an Australian metropolitan setting
High-resolution screening methodologies which enable the differentiation of Chlamydia trachomatis at the strain level, directly from clinical samples, can provide the detailed information required for epidemiological questions such as the dynamics of treatment failure. In addition, they give a detailed snapshot of circulating C. trachomatis genetic variation, data which are currently lacking for the Australian population. In the context of two Australian clinical trials, we assessed the genetic diversity of C. trachomatis and compared these to strains circulating globally. We used high-resolution multilocus sequence typing (MLST) of five highly variable genetic regions of C. trachomatis to examine variation in Australia. Samples with established genovars were drawn from a pool of 880 C. trachomatis-positive samples from two clinical studies, whereby 76 sample pairs which remained C. trachomatis-positive for the same genovar after treatment underwent MLST analysis to distinguish between treatment failure and reinfection. MLST analysis revealed a total of 25 sequence types (STs), six new allele variants and seven new STs not described anywhere else in the world, when compared to those in the international C. trachomatis MLST database. Of the eight most common global STs, seven were found in Australia (four derived from men who have sex with men (MSM) and three from heterosexuals). Newly identified STs were predominantly found in samples from the MSM population. In conclusion, MLST provided a diverse C. trachomatis strain profile, with novel circulating STs, and could be used to identify local sexual networks to focus on interventions such as testing and partner notification to prevent reinfection.
Bacterial Load of Chlamydia trachomatis in the Posterior Oropharynx, Tonsillar Fossae, and Saliva among Men Who Have Sex with Men with Untreated Oropharyngeal Chlamydia
(AMER SOC MICROBIOLOGY, 2020-01-01)
The aim of this study was to determine whether Chlamydia trachomatis could be detected in saliva and if infection is specific to an anatomical site in the oropharynx. Men who have sex with men (MSM) who were diagnosed with oropharyngeal chlamydia at the Melbourne Sexual Health Centre in 2017-2018 were invited to participate upon returning for treatment. Swabs at the tonsillar fossae and posterior oropharynx and a saliva sample were collected. Throat samples were tested for C. trachomatis by the Aptima Combo 2 assay. The bacterial loads of C. trachomatis in all samples were assessed by quantitative PCR (qPCR) detecting the ompA gene. We calculated the positivity and bacterial load of C. trachomatis for all samples. Forty-two MSM were included. The median age was 28 years (interquartile range [IQR], 24 to 33 years). Thirty-two participants (76.2%; 95% confidence interval [CI], 60.5% to 87.9%) had C. trachomatis detected by qPCR at both the tonsillar fossae and the posterior oropharynx, followed by 9.5% (n = 4; 95% CI, 2.7% to 22.6%) positive at the posterior oropharynx only and 4.8% (n = 2; 95% CI, 0.58% to 16.2%) positive at the tonsillar fossae only. Twenty-nine MSM had C. trachomatis detected in saliva (69.0%; 95% CI, 52.9% to 82.3%). The median C. trachomatis load in saliva was 446 copies/ml (IQR, 204 to 1,390 copies/ml), that in the tonsillar fossae was 893 copies/swab (IQR, 390 to 13,224 copies/ml), and that in the posterior oropharynx was 1,204 copies/swab (IQR, 330 to 16,211). There was no significant difference in C. trachomatis load between the tonsillar fossae and the posterior oropharynx (P = 0.119). Among MSM with oropharyngeal chlamydia, nearly three-quarters had chlamydia DNA detected in saliva, although the viability and implications for transmission are unknown.
The Victorian Intergenerational Health Cohort Study (VIHCS): Study design of a preconception cohort from parent adolescence to offspring childhood
BACKGROUND: There is increasing evidence that parental determinants of offspring early life development begin well before pregnancy. OBJECTIVES: We established the Victorian Intergenerational Health Cohort Study (VIHCS) to examine the contributions of parental mental health, substance use, and socio-economic characteristics before pregnancy to child emotional, physical, social, and cognitive development. POPULATION: Men and women were recruited from the Victorian Adolescent Health Cohort (VAHCS), an existing cohort study beginning in 1992 that assessed a representative sample of 1943 secondary school students in Victoria, Australia, repeatedly from adolescence (wave 1, mean age 14 years) to adulthood (wave 10, mean age 35 years). METHODS: Victorian Adolescent Health Cohort participants with children born between 2006 and 2013 were recruited to VIHCS and invited to participate during trimester three, at 2 months postpartum, and 1 year postpartum. Parental mental health, substance use and socio-economic characteristics were assessed repeatedly throughout; infant characteristics were assessed postnatally and in infancy. Data will be supplemented by linkage to routine datasets. A further follow-up is underway as children reach 8 years of age. PRELIMINARY RESULTS: Of the 1307 infants born to VAHCS participants between 2006 and 2013, 1030 were recruited to VIHCS. At VIHCS study entry, 18% of recruited parents had preconception common mental disorder in adolescence and young adulthood, 18% smoked daily in adolescence and young adulthood, and 6% had not completed high school. Half of VIHCS infants were female (48%), 4% were from multiple births, and 7% were preterm (<37 weeks' gestation). CONCLUSIONS: Victorian Intergenerational Health Cohort Study is a prospective cohort of 1030 children with up to nine waves of preconception parental data and three waves of perinatal parental and infant data. These will allow examination of continuities of parental health and health risks from the decades before pregnancy to offspring childhood, and the contributions of exposures before pregnancy to offspring outcomes in childhood.