Dermonecrosis caused by a spitting cobra snakebite results from toxin potentiation and is prevented by the repurposed drug varespladib.

Snakebite envenoming is a neglected tropical disease that causes substantial mortality and morbidity globally. The venom of African spitting cobras often causes permanent injury via tissue-destructive dermonecrosis at the bite site, which is ineffectively treated by current antivenoms. To address this therapeutic gap, we identified the etiological venom toxins in Naja nigricollis venom responsible for causing local dermonecrosis. While cytotoxic three-finger toxins were primarily responsible for causing spitting cobra cytotoxicity in cultured keratinocytes, their potentiation by phospholipases A2 toxins was essential to cause dermonecrosis in vivo. This evidence of probable toxin synergism suggests that a single toxin-family inhibiting drug could prevent local envenoming. We show that local injection with the repurposed phospholipase A2-inhibiting drug varespladib significantly prevents local tissue damage caused by several spitting cobra venoms in murine models of envenoming. Our findings therefore provide a therapeutic strategy that may effectively prevent life-changing morbidity caused by snakebite in rural Africa.

Ceftobiprole for Treatment of Complicated Staphylococcus aureus Bacteremia.

BACKGROUND: Ceftobiprole is a cephalosporin that may be effective for treating complicated Staphylococcus aureus bacteremia, including methicillin-resistant S. aureus. METHODS: In this phase 3, double-blind, double-dummy, noninferiority trial, adults with complicated S. aureus bacteremia were randomly assigned in a 1:1 ratio to receive ceftobiprole at a dose of 500 mg intravenously every 6 hours for 8 days and every 8 hours thereafter, or daptomycin at a dose of 6 to 10 mg per kilogram of body weight intravenously every 24 hours plus optional aztreonam (at the discretion of the trial-site investigators). The primary outcome, overall treatment success 70 days after randomization (defined as survival, bacteremia clearance, symptom improvement, no new S. aureus bacteremia-related complications, and no receipt of other potentially effective antibiotics), with a noninferiority margin of 15%, was adjudicated by a data review committee whose members were unaware of the trial-group assignments. Safety was also assessed. RESULTS: Of 390 patients who underwent randomization, 387 (189 in the ceftobiprole group and 198 in the daptomycin group) had confirmed S. aureus bacteremia and received ceftobiprole or daptomycin (modified intention-to-treat population). A total of 132 of 189 patients (69.8%) in the ceftobiprole group and 136 of 198 patients (68.7%) in the daptomycin group had overall treatment success (adjusted difference, 2.0 percentage points; 95% confidence interval [CI], -7.1 to 11.1). Findings appeared to be consistent between the ceftobiprole and daptomycin groups in key subgroups and with respect to secondary outcomes, including mortality (9.0% and 9.1%, respectively; 95% CI, -6.2 to 5.2) and the percentage of patients with microbiologic eradication (82.0% and 77.3%; 95% CI, -2.9 to 13.0). Adverse events were reported in 121 of 191 patients (63.4%) who received ceftobiprole and 117 of 198 patients (59.1%) who received daptomycin; serious adverse events were reported in 36 patients (18.8%) and 45 patients (22.7%), respectively. Gastrointestinal adverse events (primarily mild nausea) were more frequent with ceftobiprole. CONCLUSIONS: Ceftobiprole was noninferior to daptomycin with respect to overall treatment success in patients with complicated S. aureus bacteremia. (Funded by Basilea Pharmaceutica International and the U.S. Department of Health and Human Services; ERADICATE ClinicalTrials.gov number, NCT03138733.).

Streamlining the Analysis of Proteins from Snake Venom.

Investigating snake venom is necessary for developing new treatments for envenoming and harnessing the therapeutic potential that lies within venom toxins. Despite considerable efforts in previous research, several technical challenges remain for characterizing the individual components within such complex mixtures. Here, we present native and top-down mass spectrometry (MS) workflows that enable the analysis of individual venom proteins within complex mixtures and showcase the utility of these methodologies on King cobra (Ophiophagus hannah) venom. First, we coupled ion mobility spectrometry for separation and electron capture dissociation for charge reduction to resolve highly convoluted mass spectra containing multiple proteins with masses ranging from 55 to 127 kDa. Next, we performed a top-down glycomic analysis of a 25.5 kDa toxin, showing that this protein contains a fucosylated complex glycan. Finally, temperature-controlled nanoelectrospray mass spectrometry facilitated the top-down sequence analysis of a ß-cardiotoxin, which cannot be fragmented by collisional energy due to its disulfide bond pattern. The work presented here demonstrates the applicability of new and promising MS methods for snake venom analysis.

Identifying Effective Durations of Antibiotic Therapy for the Treatment of Carbapenem-resistant Enterobacterales Bloodstream Infections: A Multicenter Observational Study.

In a propensity-score-weighted cohort of 183 adults with carbapenem-resistant Enterobacterales bacteremia at 24 US hospitals, patients receiving short courses of active therapy (7-10 days, median 9 days) experienced similar odds of recurrent bacteremia or death within 30 days as those receiving prolonged courses of active therapy (14-21 days, median 14 days).

Interventions to de-implement unnecessary antibiotic prescribing for ear infections (DISAPEAR Trial): protocol for a cluster-randomized trial.

BACKGROUND: Watchful waiting management for acute otitis media (AOM), where an antibiotic is used only if the child's symptoms worsen or do not improve over the subsequent 2-3 days, is an effective approach to reduce antibiotic exposure for children with AOM. However, studies to compare the effectiveness of interventions to promote watchful waiting are lacking. The objective of this study is to compare the effectiveness and implementation outcomes of two pragmatic, patient-centered interventions designed to facilitate use of watchful waiting in clinical practice. METHODS: This will be a cluster-randomized trial utilizing a hybrid implementation-effectiveness design. Thirty-three primary care or urgent care clinics will be randomized to one of two interventions: a health systems-level intervention alone or a health systems-level intervention combined with use of a shared decision-making aid. The health systems-level intervention will include engagement of a clinician champion at each clinic, changes to electronic health record antibiotic orders to facilitate delayed antibiotic prescriptions as part of a watchful waiting strategy, quarterly feedback reports detailing clinicians' use of watchful waiting individually and compared with peers, and virtual learning sessions for clinicians. The hybrid intervention will include the health systems-level intervention plus a shared decision-making aid designed to inform decision-making between parents and clinicians with best available evidence. The primary outcomes will be whether an antibiotic was ultimately taken by the child and parent satisfaction with their child's care. We will explore the differences in implementation effectiveness by patient population served, clinic type, clinical setting, and organization. The fidelity, acceptability, and perceived appropriateness of the interventions among different clinician types, patient populations, and clinical settings will be compared. We will also conduct formative qualitative interviews and surveys with clinicians and administrators, focus groups and surveys of parents of patients with AOM, and engagement of two stakeholder advisory councils to further inform the interventions. DISCUSSION: This study will compare the effectiveness of two pragmatic interventions to promote use of watchful waiting for children with AOM to reduce antibiotic exposure and increase parent satisfaction, thus informing national antibiotic stewardship policy development. CLINICAL TRIAL REGISTRATION: NCT06034080.

Motivations for completing pulmonary rehabilitation - A qualitative analysis.

Background: Previous studies have focused on demographic factors that might predict non-completion of pulmonary rehabilitation (PR). We aimed to identify key modifiable factors that promote completion of PR. Methods: A mixed methods survey was offered to participants completing a discharge assessment following PR. Descriptive statistics and inductive thematic analysis were used to analyse the survey responses, with investigator triangulation. Results: 62 of 187 (33%) patients attending a PR discharge assessment between November 2022 and April 2023 returned the anonymised survey. Desire to improve health and wellbeing was the main reason for both initially committing to a course and for continuing with PR past transient thoughts of leaving. The positive impact of staff was the second most common reason. The enjoyment of the PR programme, being held accountable to attend classes, and the importance of other group members were other key themes identified. Conclusions: In conclusion, our findings suggest PR services need to implement strategies which ensure regular promotion and reinforcement of the health benefits of PR as well as implementation of PR modalities which best monopolise on the positive impact skilled staff have on motivating patients to complete PR.

Associations with unplanned repeat irrigation and debridement of native septic arthritis.

PURPOSE: To identify associations with unplanned repeat irrigation and debridement (I&D) after arthrotomy for native septic arthritis. METHODS: A retrospective review identified patients with native septic arthritis treated with open arthrotomies. The primary outcome was unplanned repeat I&D within 90 days. Associations evaluated for included comorbidities, ability to bear weight, fever, immunosuppressed status, purulence, C-reactive protein, erythrocyte sedimentation rate, white blood cell count (synovial fluid and serum levels), and synovial fluid polymorphonuclear cell percentage (PMN%). RESULTS: There were 59 arthrotomies in 53 patients involving the knee (n = 32), shoulder (n = 10), elbow (n = 8), ankle (n = 6), and hip (n = 3). The median patient age was 52, and a 71.2% were male. An unplanned repeat I&D was required in 40.7% (n = 24). The median time to the second I&D was 4 days (interquartile range 3 to 9). On univariate analysis, unplanned repeat I&Ds were associated with fever (p = 0.03), purulence (p = 0.01), bacteria growth on cultures (p = 0.02), and the use of deep drains (p = 0.05). On multivariate analysis, the only variables that remained associated with unplanned repeat I&Ds were fever (odds ratio (OR) 5.5, 95% confidence interval (CI) 1.3, 23.6, p = 0.02) and purulence (OR 5.3, CI 1.1, 24.4, p = 0.03). CONCLUSIONS: An unplanned repeat I&D was required in 40.7% of patients and was associated with fever and purulence. These findings highlight the difficulty of controlling these infections and support the need for future research into better methods of management. LEVEL OF EVIDENCE: Diagnostic, Level III.

Sustainability of Interventions to Increase Guideline-Concordant Durations of Antibiotic Therapy for Children with Acute Otitis Media.

Two low-cost pragmatic interventions (change in the options in the electronic health record; change in the electronic health record plus education plus feedback comparing prescribing with peers) to improve prescribing of guideline-concordant short antibiotic durations for children 2 years and older with uncomplicated acute otitis media were highly effective and results were sustained 18 months after discontinuation of the active components of the interventions.

NRF2 loss recapitulates heritable impacts of paternal cigarette smoke exposure.

Paternal cigarette smoke (CS) exposure is associated with increased risk of behavioral disorders and cancer in offspring, but the mechanism has not been identified. Here we use mouse models to investigate mechanisms and impacts of paternal CS exposure. We demonstrate that CS exposure induces sperm DNAme changes that are partially corrected within 28 days of removal from CS exposure. Additionally, paternal smoking is associated with changes in prefrontal cortex DNAme and gene expression patterns in offspring. Remarkably, the epigenetic and transcriptional effects of CS exposure that we observed in wild type mice are partially recapitulated in Nrf2-/- mice and their offspring, independent of smoking status. Nrf2 is a central regulator of antioxidant gene transcription, and mice lacking Nrf2 consequently display elevated oxidative stress, suggesting that oxidative stress may underlie CS-induced heritable epigenetic changes. Importantly, paternal sperm DNAme changes do not overlap with DNAme changes measured in offspring prefrontal cortex, indicating that the observed DNAme changes in sperm are not directly inherited. Additionally, the changes in sperm DNAme associated with CS exposure were not observed in sperm of unexposed offspring, suggesting the effects are likely not maintained across multiple generations.

A Multicenter, Prospective, Observational, Cohort-Controlled Study of Clinical Outcomes Following Coronavirus Disease 2019 (COVID-19) Convalescent Plasma Therapy in Hospitalized Patients With COVID-19.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused high inpatient mortality and morbidity throughout the world. COVID-19 convalescent plasma (CCP) has been utilized as a potential therapy for patients hospitalized with coronavirus disease 2019 (COVID-19) pneumonia. This study evaluated the outcomes of hospitalized patients with COVID-19 treated with CCP in a prospective, observational, multicenter trial. METHODS: From April through August 2020, hospitalized patients with COVID-19 at 16 participating hospitals in Colorado were enrolled and treated with CCP and compared with hospitalized patients with COVID-19 who were not treated with convalescent plasma. Plasma antibody levels were determined following the trial, given that antibody tests were not approved at the initiation of the trial. CCP-treated and untreated hospitalized patients with COVID-19 were matched using propensity scores followed by analysis for length of hospitalization and inpatient mortality. RESULTS: A total of 542 hospitalized patients with COVID-19 were enrolled at 16 hospitals across the region. A total of 468 hospitalized patients with COVID-19 were entered into propensity score matching with 188 patients matched for analysis in the CCP-treatment and control arms. Fine-Gray models revealed increased length of hospital stay in CCP-treated patients and no change in inpatient mortality compared with controls. In subgroup analysis of CCP-treated patients within 7 days of admission, there was no difference in length of hospitalization and inpatient mortality. CONCLUSIONS: These data show that treatment of hospitalized patients with COVID-19 treated with CCP did not significantly improve patient hospitalization length of stay or inpatient mortality.

Increasing Guideline-Concordant Durations of Antibiotic Therapy for Acute Otitis Media.

OBJECTIVE: To compare the effectiveness of 2 interventions in improving prescribing of guideline-concordant durations of therapy for acute otitis media (AOM). STUDY DESIGN: This was a quasi-experimental mixed methods analysis that compared a bundled quality improvement intervention consisting of individualized audit and feedback, education, and electronic health record (EHR) changes to an EHR-only intervention. The bundle was implemented in 3 pediatric clinics from January to August 2020 and an EHR-only intervention was implemented in 6 family medicine clinics. The primary outcome measure was prescription of an institutional guideline-concordant 5-day duration of therapy for children ≥2 years of age with uncomplicated AOM. Propensity score matching and differences-in-differences analysis weighted with inverse probability of treatment were completed. Implementation outcomes were assessed using the Reach, Effectiveness, Adoption, Implementation, Maintenance Framework. Balance measures included treatment failure and recurrence. RESULTS: In total, 1017 encounters for AOM were included from February 2019 to August 2020. Guideline-concordant prescribing increased from 14.4% to 63.8% (difference = 49.4%) in clinics that received the EHR-only intervention and from 10.6% to 85.2% (difference = 74.6%) in clinics that received the bundled intervention. In the adjusted analysis, the bundled intervention improved guideline-concordant durations by an additional 26.4% (P < .01) compared with the EHR-only intervention. Providers identified EHR-prescription field changes as the most helpful components. There were no differences in treatment failure or recurrence rates between baseline and either intervention. CONCLUSIONS: Both interventions resulted in improved prescribing of guideline-concordant durations of antibiotics. The bundled intervention improved prescribing more than an EHR-only intervention and was acceptable to providers.

Experimental infection with the hookworm, Necator americanus, is associated with stable gut microbial diversity in human volunteers with relapsing multiple sclerosis.

BACKGROUND: Helminth-associated changes in gut microbiota composition have been hypothesised to contribute to the immune-suppressive properties of parasitic worms. Multiple sclerosis is an immune-mediated autoimmune disease of the central nervous system whose pathophysiology has been linked to imbalances in gut microbial communities. RESULTS: In the present study, we investigated, for the first time, qualitative and quantitative changes in the faecal bacterial composition of human volunteers with remitting multiple sclerosis (RMS) prior to and following experimental infection with the human hookworm, Necator americanus (N+), and following anthelmintic treatment, and compared the findings with data obtained from a cohort of RMS patients subjected to placebo treatment (PBO). Bacterial 16S rRNA high-throughput sequencing data revealed significantly decreased alpha diversity in the faecal microbiota of PBO compared to N+ subjects over the course of the trial; additionally, we observed significant differences in the abundances of several bacterial taxa with putative immune-modulatory functions between study cohorts. Parabacteroides were significantly expanded in the faecal microbiota of N+ individuals for which no clinical and/or radiological relapses were recorded at the end of the trial. CONCLUSIONS: Overall, our data lend support to the hypothesis of a contributory role of parasite-associated alterations in gut microbial composition to the immune-modulatory properties of hookworm parasites.

Thinking Beyond the "Core" Antibiotic Stewardship Interventions: Shifting the Onus for Appropriate Antibiotic Use from Stewardship Teams to Prescribing Clinicians.

United States guidance for hospital antibiotic stewardship has emphasized prospective audit and feedback and prior authorization of select antibiotics as core interventions. These remain the most common interventions implemented by stewardship programs. Although these approaches have been shown to reduce unnecessary antibiotic use, they incorrectly put the onus for appropriate antibiotic use on the stewardship team rather than the prescribing clinician. We propose that a primary focus of stewardship programs should be implementation of broader interventions that engage frontline clinicians and equip them with tools to integrate antibiotic stewardship into their own daily practice, thus reducing the need for day-to-day stewardship team oversite. We discuss a framework of broader interventions and policies that will facilitate this paradigm shift.

Exclusive dependence of IL-10Rα signalling on intestinal microbiota homeostasis and control of whipworm infection.

The whipworm Trichuris trichiura is a soil-transmitted helminth that dwells in the epithelium of the caecum and proximal colon of their hosts causing the human disease, trichuriasis. Trichuriasis is characterized by colitis attributed to the inflammatory response elicited by the parasite while tunnelling through intestinal epithelial cells (IECs). The IL-10 family of receptors, comprising combinations of subunits IL-10Rα, IL-10Rß, IL-22Rα and IL-28Rα, modulates intestinal inflammatory responses. Here we carefully dissected the role of these subunits in the resistance of mice to infection with T. muris, a mouse model of the human whipworm T. trichiura. Our findings demonstrate that whilst IL-22Rα and IL-28Rα are dispensable in the host response to whipworms, IL-10 signalling through IL-10Rα and IL-10Rß is essential to control caecal pathology, worm expulsion and survival during T. muris infections. We show that deficiency of IL-10, IL-10Rα and IL-10Rß results in dysbiosis of the caecal microbiota characterised by expanded populations of opportunistic bacteria of the families Enterococcaceae and Enterobacteriaceae. Moreover, breakdown of the epithelial barrier after whipworm infection in IL-10, IL-10Rα and IL-10Rß-deficient mice, allows the translocation of these opportunistic pathogens or their excretory products to the liver causing organ failure and lethal disease. Importantly, bone marrow chimera experiments indicate that signalling through IL-10Rα and IL-10Rß in haematopoietic cells, but not IECs, is crucial to control worm expulsion and immunopathology. These findings are supported by worm expulsion upon infection of conditional mutant mice for the IL-10Rα on IECs. Our findings emphasize the pivotal and complex role of systemic IL-10Rα signalling on immune cells in promoting microbiota homeostasis and maintaining the intestinal epithelial barrier, thus preventing immunopathology during whipworm infections.

High efficiency rare sperm separation from biopsy samples in an inertial focusing device.

Immotile and rare sperm isolation from a complex cell background is an essential process for infertility treatment. The traditional sperm collection process from a biopsy sample requires long, tedious searches, yet still results in low sperm retrieval. In this work, a high recovery, high throughput sperm separation process is proposed for the clinical biopsy sperm retrieval process. It is found that sperm have different focusing positions compared with non-sperm cells in the inertial flow, which is explained by a sperm alignment phenomenon. Separation in the spiral channel device results in a 95.6% sperm recovery in which 87.4% of non-sperm cells get removed. Rare sperm isolation from a clinical biopsy sample is performed with the current approach. The chance of finding sperm is shown to increase 8.2 fold in the treated samples. The achieved results highly support this method being used for the development of a rapid biopsy sperm sorting process. In addition, the mechanism was proposed and can be applied for the high-efficiency separation of non-spherical particles in general.

A Novel Approach to Evaluate Antibiotic Utilization Across the Spectrum of Inpatient and Ambulatory Care and Implications for Prioritization of Antibiotic Stewardship Efforts.

BACKGROUND: Antibiotic overuse remains a significant problem. The objective of this study was to develop a methodology to evaluate antibiotic use across inpatient and ambulatory care sites in an integrated healthcare system to prioritize antibiotic stewardship efforts. METHODS: We conducted an epidemiologic study of antibiotic use across an integrated healthcare system on 12 randomly selected days from 2017 to 2018. For inpatients and perioperative patients, administrations of antibiotics were recorded, whereas prescriptions were recorded for outpatients. RESULTS: On the study days, 10.9% (95% confidence interval [CI], 10.6%-11.3%) of patients received antibiotics. Of all antibiotics, 54.1% were from ambulatory care (95% CI, 52.6%-55.7%), 38.0% were from the hospital (95% CI, 36.6%-39.5%), and 7.8% (95% CI, 7.1%-8.7%) were perioperative. The emergency department/urgent care centers, adult outpatient clinics, and adult non-critical care inpatient wards accounted for 26.4% (95% CI, 25.0%-27.7%), 23.8% (95% CI, 22.6%-25.2%), and 23.9% (95% CI, 22.7%-25.3%) of antibiotic use, respectively. Only 9.2% (95% CI, 8.3%-10.1%) of all antibiotics were administered in critical care units. Antibiotics with a broad spectrum of gram-negative activity accounted for 30.4% (95% CI, 29.0%-31.9%) of antibiotics. Infections of the respiratory tract were the leading indication for antibiotics. CONCLUSIONS: In an integrated healthcare system, more than half of antibiotic use occurred in the emergency department/urgent care centers and outpatient clinics. Antibiotics with a broad spectrum of gram-negative activity accounted for a large portion of antibiotic use. Analysis of antibiotic utilization across the spectrum of inpatient and ambulatory care is useful to prioritize antibiotic stewardship efforts.

Effectiveness of Shorter Versus Longer Durations of Therapy for Common Inpatient Infections Associated With Bacteremia: A Multicenter, Propensity-Weighted Cohort Study.

BACKGROUND: National guidelines for pneumonia (PNA), urinary tract infection (UTI), and acute bacterial skin and skin structure infection (ABSSSI) do not address treatment duration for infections associated with bacteremia. We evaluated clinical outcomes of patients receiving shorter (5-9 days) versus longer (10-15 days) duration of antibiotics. METHODS: This was a multicenter retrospective cohort study of inpatients with uncomplicated PNA, UTI, or ABSSSI and associated bacteremia. The primary outcome was clinical failure, a composite of rehospitalization, reinitiation of antibiotics, or all-cause mortality within 30 days of antibiotic completion. Secondary outcomes included individual components of the primary outcome, Clostridioides difficile infection, and antibiotic-related adverse effects necessitating change in therapy. A propensity score-weighted logistic regression model was used to mitigate potential bias associated with nonrandom assignment of treatment duration. RESULTS: Of 408 patients included, 123 received a shorter treatment duration (median 8 days) and 285 received a longer duration (median 13 days). In the propensity-weighted analysis, the probability of the primary outcome was 13.5% in the shorter group and 11.1% in the longer group (average treatment effect, 2.4%; odds ratio [OR], 1.25; 95% confidence interval [CI], .65-2.40; P = .505). However, shorter courses were associated with higher probability of restarting antibiotics (OR, 1.62; 95% CI, 1.01-2.61; P = .046) and C. difficile infection (OR, 4.01; 95% CI, 2.21-7.59; P < .0001). CONCLUSIONS: Shorter courses of antibiotic treatment for PNA, UTI, and ABSSSI with bacteremia were not associated with increased overall risk of clinical failure; however, prospective studies are needed to further evaluate the effectiveness of shorter treatment durations.

Antibiotic Prescribing Patterns for Acute Otitis Media for Children 2 Years and Older.

OBJECTIVE: To determine the frequency that non-first-line antibiotics, safety-net antibiotic prescriptions (SNAPS), and longer than recommended durations of antibiotics were prescribed for children ≥2 years of age with acute otitis media and examine patient and system level factors that contributed to these outcomes. STUDY DESIGN: Children age ≥2 years with acute otitis media seen at Denver Health Medical Center outpatient locations from January to December 2018 were included. The percentages of patients who received first-line antibiotics, SNAPs, and recommended durations of antibiotics were determined. Factors associated with non-first-line and longer than recommended antibiotic durations were evaluated using multivariate logistic regression modeling. RESULTS: Of the 1025 visits evaluated, 98.0% were prescribed an antibiotic; only 4.5% of antibiotics were SNAPs. Non-first-line antibiotics were prescribed to 18.8% of patients. Most antibiotic durations (94.1%) were longer than the institution recommended 5 days and 54.3% were ≥10 days. Private insurance was associated with non-first-line antibiotics (aOR, 1.89; 95% CI, 1; 14-3.14, P = .01). Patients who were younger (2-5 years; aOR 2.01; 95% CI, 1.32-3.05; P < .001) or seen in emergency/urgent care sites (aOR, 1.73; 95% CI, 1.26-2.38; P < .001) were more likely to receive ≥10 days of antibiotic compared with those in pediatric clinics. CONCLUSIONS: Antibiotic stewardship interventions that emphasize the duration of antibiotic therapy as well as the use of SNAPs or observation may be higher yield than those focusing on first-line therapy alone. Numerous system and patient level factors are associated with off-guideline prescribing.

Young women with poor ovarian response exhibit epigenetic age acceleration based on evaluation of white blood cells using a DNA methylation-derived age prediction model.

STUDY QUESTION: Is poor ovarian response associated with a change in predicted age based on a DNA methylation-derived age prediction model (the Horvath algorithm) in white blood cells (WBCs) or cumulus cells (CCs)? SUMMARY ANSWER: In young women, poor ovarian response is associated with epigenetic age acceleration within WBC samples but is not associated with age-related changes in CC. WHAT IS KNOWN ALREADY: The majority of human tissues follow predictable patterns of methylation which can be assessed throughout a person's lifetime. DNA methylation patterns may serve as informative biomarkers of aging within various tissues. Horvath's 'epigenetic clock', which is a DNA methylation-derived age prediction model, accurately predicts a subject's true chronologic age when applied to WBC but not to CC. STUDY DESIGN, SIZE, DURATION: A prospective cohort study was carried out involving 175 women undergoing ovarian stimulation between February 2017 and December 2018. Women were grouped according to a poor (≤5 oocytes retrieved) or good (>5 oocytes) response to ovarian stimulation. Those with polycystic ovary syndrome (PCOS) (n = 35) were placed in the good responder group. PARTICIPANTS/MATERIALS, SETTING, METHODS: DNA methylation patterns from WBC and CC were assessed for infertile patients undergoing ovarian stimulation at a university-affiliated private practice. DNA was isolated from peripheral blood samples and CC. Bisulfite conversion was then performed and a DNA methylation array was utilized to measure DNA methylation levels throughout the genome. Likelihood ratio tests were utilized to assess the relationship between predicted age, chronologic age and ovarian response. MAIN RESULTS AND THE ROLE OF CHANCE: The Horvath-predicted age for WBC samples was consistent with patients' chronologic age. However, predicted age from analysis of CC was younger than chronologic age. In subgroup analysis of women less than 38 years of age, poor ovarian response was associated with an accelerated predicted age in WBC (P = 0.017). Poor ovarian response did not affect the Horvath-predicted age based on CC samples (P = 0.502). No alternative methylation-based calculation was identified to be predictive of age for CC. LIMITATIONS, REASONS FOR CAUTION: To date, analyses of CC have failed to identify epigenetic changes that are predictive of the aging process within the ovary. Despite the poor predictive nature of both the Horvath model and the novel methylation-based age prediction model described here, it is possible that our efforts failed to identify appropriate sites which would result in a successful age-prediction model derived from the CC epigenome. Additionally, lower DNA input for CC samples compared to WBC samples was a methodological limitation. We acknowledge that a universally accepted definition of poor ovarian response is lacking. Furthermore, women with PCOS were included and therefore the group of good responders in the current study may not represent a population with entirely normal methylation profiles. WIDER IMPLICATIONS OF THE FINDINGS: The process of ovarian and CC aging continues to be poorly understood. Women who demonstrate poor ovarian response to stimulation represent a common clinical challenge, so clarifying the exact biological changes that occur within the ovary over time is a worthwhile endeavor. The data from CC support a view that hormonally responsive tissues may possess distinct epigenetic aging patterns when compared with other tissue types. Future studies may be able to determine whether alternative DNA methylation sites can accurately predict chronologic age or ovarian response to stimulation from CC samples. Going forward, associations between epigenetic age acceleration and reproductive and general health consequences must also be clearly defined. STUDY FUNDING/COMPETING INTEREST(S): No external funding was obtained for the study and there are no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

The Role of the Epididymis and the Contribution of Epididymosomes to Mammalian Reproduction.

It is well-established that testicular spermatozoa are immature and acquire motility and fertilization capabilities during transit throughout the epididymis. The epididymis is a duct-like organ that connects the testis to the vas deferens and is comprised of four anatomical regions: the initial segment, caput, corpus, and cauda. Sperm maturation occurs during epididymal transit by the interaction of sperm cells with the unique luminal environment of each epididymal region. In this review we discuss the epididymis as an essential reproductive organ responsible for sperm concentration, maturation (including sperm motility acquisition and fertilizing ability), protection and storage. Importantly, we also discuss specific characteristics and roles of epididymal-derived exosomes (epididymosomes) in establishing sperm competency within the intricate process of reproduction. This review suggests that an increasing body of evidence is working to develop a complete picture of the role of the epididymis in male reproduction, offspring health, and disease susceptibility.