The Efficacy of Metformin as a Therapeutic Agent in the Treatment of Acne Vulgaris: A Systematic Review.

A large portion of the world's population is affected by acne vulgaris (AV), with many of these individuals being adolescents. The underlying mechanism of AV is hyperkeratinization and Cutibacterium acnes infection of the pilosebaceous follicle secondary to excessive stimulation of sebaceous glands by androgens. Metformin is a biguanide medication primarily used in efforts to lower patients' sugar levels in the management of type 2 diabetes. It has been proven to reduce levels of circulating androgens in patients with insulin resistance, indicating its potential for treating AV. A search strategy was developed and performed using the databases Ovid Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (EMBASE), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Controlled Register of Trials (CENTRAL), and Web of Science. The keywords "metformin" and "acne" were searched, along with related Medical Subject Headings (MeSH) and other subject headings. Studies that met the inclusion criteria were controlled trials, published after 2010, and in the English language. Participants with and without comorbidities such as polycystic ovary syndrome (PCOS) were considered. Two independent reviewers screened studies based on predefined criteria and extracted data from each study, which were quantitatively combined. A total of 15 studies were included in this systematic review. Across the 15 studies, there were 1,046 participants, with 13 studies looking exclusively at women with PCOS. Of the remaining two studies, one examined males with altered metabolic profiles, while the other included men and women with moderate AV. Notable risks of bias included studies that did not exclusively state the blindness of the study. Of the studies that were examined, 13 showed that metformin reduces AV, with seven studies showing statistical significance. Acne vulgaris is an inflammatory condition that has plagued patients for years due to the limited treatment options available. The hyperglycemic medication metformin, used in the management of type 2 diabetes, is being explored as a novel therapeutic that can possibly be repurposed for the treatment of AV. The use of metformin in AV is hypothesized to disrupt the proposed linkage between insulin resistance and AV proliferation. This proposed research could offer physicians a new option for the treatment of AV as well as render an alternative AV treatment for patients.

"Multiplexed screen identifies a Pseudomonas aeruginosa -specific small molecule targeting the outer membrane protein OprH and its interaction with LPS".

The surge of antimicrobial resistance threatens efficacy of current antibiotics, particularly against Pseudomonas aeruginosa , a highly resistant gram-negative pathogen. The asymmetric outer membrane (OM) of P. aeruginosa combined with its array of efflux pumps provide a barrier to xenobiotic accumulation, thus making antibiotic discovery challenging. We adapted PROSPECT 1 , a target-based, whole-cell screening strategy, to discover small molecule probes that kill P. aeruginosa mutants depleted for essential proteins localized at the OM. We identified BRD1401, a small molecule that has specific activity against a P. aeruginosa mutant depleted for the essential lipoprotein, OprL. Genetic and chemical biological studies identified that BRD1401 acts by targeting the OM ß-barrel protein OprH to disrupt its interaction with LPS and increase membrane fluidity. Studies with BRD1401 also revealed an interaction between OprL and OprH, directly linking the OM with peptidoglycan. Thus, a whole-cell, multiplexed screen can identify species-specific chemical probes to reveal novel pathogen biology.

Syphilis and cardiovascular risk: a Taiwanese registry.

BACKGROUND AND AIMS: Studies on the impact of syphilis on the cardiovascular system in large populations are limited. This study investigated the effects of syphilis on cardiovascular outcomes. METHODS: Medical records from 2010 to 2015 were retrieved from the Taiwan National Health Insurance Research Database, linked to the Notifiable Infectious Diseases database from the Taiwan Centers for Disease Control. Patients with syphilis were identified, excluding those with missing information, under 20 years of age, or with a history of human immunodeficiency virus infection, acute myocardial infarction, heart failure, aortic regurgitation, replacement of the aortic valve, aneurysm and/or dissection of the aorta, atrial fibrillation, ischaemic stroke, haemorrhagic stroke, and venous thromboembolism. Primary outcomes included new-onset acute myocardial infarction, heart failure, aortic regurgitation, aneurysm and dissection of the aorta, atrial fibrillation, ischaemic stroke, haemorrhagic stroke, venous thromboembolism, cardiovascular death, and all-cause mortality. RESULTS: A total of 28 796 patients with syphilis were identified from 2010 to 2015. After exclusions and frequency matching, 20 601 syphilis patients and 20 601 non-syphilis patients were analysed. The relative rate (RR) was utilized in the analysis, as the competing risk of death was not considered. Compared with patients without syphilis, patients with syphilis had increased risks of acute myocardial infarction (RR 38%, 95% confidence interval [CI] 1.19-1.60, P < .001), heart failure (RR 88%, 95% CI 1.64-2.14, P < .001), aortic regurgitation (RR 81%, 95% CI 1.18-2.75, P = .006), atrial fibrillation (RR 45%, 95% CI 1.20-1.76, P < .001), ischaemic stroke (RR 68%, 95% CI 1.52-1.87, P < .001), haemorrhagic stroke (RR 114%, 95% CI 1.74-2.64, P < .001), venous thromboembolism (RR 67%, 95% CI 1.23-2.26, P = .001), cardiovascular death (RR 155%, 95% CI 2.11-3.08, P < .001), and all-cause death (RR 196%, 95% CI 2.74-3.19, P < .001) but not for aneurysm and dissection of the aorta. CONCLUSIONS: This study demonstrates that patients with syphilis have a higher risk of cardiovascular events and all-cause mortality compared with those without syphilis.

Durability of Original Monovalent mRNA Vaccine Effectiveness Against COVID-19 Omicron-Associated Hospitalization in Children and Adolescents - United States, 2021-2023.

Pediatric COVID-19 vaccination is effective in preventing COVID-19-related hospitalization, but duration of protection of the original monovalent vaccine during SARS-CoV-2 Omicron predominance merits evaluation, particularly given low coverage with updated COVID-19 vaccines. During December 19, 2021-October 29, 2023, the Overcoming COVID-19 Network evaluated vaccine effectiveness (VE) of ≥2 original monovalent COVID-19 mRNA vaccine doses against COVID-19-related hospitalization and critical illness among U.S. children and adolescents aged 5-18 years, using a case-control design. Too few children and adolescents received bivalent or updated monovalent vaccines to separately evaluate their effectiveness. Most case-patients (persons with a positive SARS-CoV-2 test result) were unvaccinated, despite the high frequency of reported underlying conditions associated with severe COVID-19. VE of the original monovalent vaccine against COVID-19-related hospitalizations was 52% (95% CI = 33%-66%) when the most recent dose was administered <120 days before hospitalization and 19% (95% CI = 2%-32%) if the interval was 120-364 days. VE of the original monovalent vaccine against COVID-19-related hospitalization was 31% (95% CI = 18%-43%) if the last dose was received any time within the previous year. VE against critical COVID-19-related illness, defined as receipt of noninvasive or invasive mechanical ventilation, vasoactive infusions, extracorporeal membrane oxygenation, and illness resulting in death, was 57% (95% CI = 21%-76%) when the most recent dose was received <120 days before hospitalization, 25% (95% CI = -9% to 49%) if it was received 120-364 days before hospitalization, and 38% (95% CI = 15%-55%) if the last dose was received any time within the previous year. VE was similar after excluding children and adolescents with documented immunocompromising conditions. Because of the low frequency of children who received updated COVID-19 vaccines and waning effectiveness of original monovalent doses, these data support CDC recommendations that all children and adolescents receive updated COVID-19 vaccines to protect against severe COVID-19.

A Spatial Omnibus Test (SPOT) for Spatial Proteomic Data.

Spatial proteomics can reveal the spatial organization of immune cells in the tumor immune microenvironment. Relating measures of spatial clustering, such as Ripley's K or Besag's L, to patient outcomes may offer important clinical insights. However, these measures require pre-specifying a radius in which to quantify clustering, yet no consensus exists on the optimal radius which may be context-specific. We propose a SPatial Omnibus Test (SPOT) which conducts this analysis across a range of candidate radii. At each radius, SPOT evaluates the association between the spatial summary and outcome, adjusting for confounders. SPOT then aggregates results across radii using the Cauchy combination test, yielding an omnibus p-value characterizing the overall degree of association. Using simulations, we verify that the type I error rate is controlled and show SPOT can be more powerful than alternatives. We also apply SPOT to an ovarian cancer study. An R package and tutorial is provided at https://github.com/sarahsamorodnitsky/SPOT.

Guanfacine for the Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents with Down Syndrome: A Retrospective Chart Review.

Study Design: Retrospective case series. Objectives: The objective of this study was to provide naturalistic data on the use of guanfacine for the treatment of attention-deficit/hyperactivity disorder (ADHD) in a clinically referred sample of youth with Down syndrome (DS). Methods: The medical records of children and adolescents with DS who received guanfacine for the treatment of ADHD from a multidisciplinary neurodevelopmental disorder clinic between September 1, 2011, and September 10, 2021, were reviewed. Demographic and clinical characteristics, guanfacine dose and treatment duration, and adverse effects were recorded. Clinical Global Impression Scale (CGI) scores for ADHD symptom severity (S) and improvement (I) were retrospectively assigned by a child and adolescent psychiatrist based on review of the clinic notes. Response to guanfacine was defined as completion of at least 12 weeks of treatment and a Clinical Global Impression Improvement subscale rating ≤2 (1 = "very much improved" or 2 = "much improved"). Results: Twenty-one patients were eligible for inclusion, of whom 17 (81%) completed at least 12 weeks of guanfacine. Ten of the 21 patients (48%; 95% confidence interval [CI]: 28%-68%) responded to treatment. The median time on guanfacine treatment covered by the clinic notes was 50.4 weeks, with a range of 0.3 weeks to 7.5 years. Thirteen patients (62%) remained on guanfacine at the time of their most recent clinic note. Nine patients had adverse events documented in their clinic notes (43%; 95% CI: 24%-63%), most commonly sleepiness (n = 7) and constipation (n = 2). Conclusion: About half of patients with DS responded to guanfacine for the treatment of ADHD and many tolerated long-term use. Study limitations primarily relate to the retrospective nature of the study and small sample size.

Tailoring Strength Training Prescriptions for People with Rheumatoid Arthritis: A Scoping Review.

Introduction: Prescribing strength training (ST) for people with rheumatoid arthritis (RA) is complicated by factors (barriers and facilitators) that affect participation. It is unclear whether guidelines include recommendations beyond prescription parameters (frequency, intensity, time, type, volume, and progression) and adequately incorporate participation factors tailored to people with RA. Objective: To summarize available recommendations to aid in the tailoring of ST prescriptions for people with RA. Methods: Medline, Embase, and CINAHL databases and gray literature were searched for guidelines, recommendations, and review articles containing ST prescription recommendations for RA. Article screening and data extraction were performed in duplicate by two reviewers. Results: Twenty-seven articles met the inclusion criteria. The recommendations address RA-specific ST participation factors including: knowledge gaps (of equipment, ST benefits, disease), memory problems, the management of joint deformity, comorbidity, the fluctuating nature of the disease and symptoms (pain, stiffness, flares), fear avoidance, motivation, need for referral to other professionals, and provision of RA-specific resources. Conclusion: This review summarizes recommendations for tailoring ST prescriptions for people with RA. Future research is required to understand how pain, symptom assessment, and unaddressed ST participation factors like sleep and medication side effects can be addressed to support ST participation amongst people with RA.

Temporal Trends in Practice Patterns After Introduction of Pediatric Hypertension Guidelines in Canada.

Importance: In 2016 and 2017, respectively, new Canadian and US guidelines for diagnosis and management of pediatric hypertension (HTN) were published. Six years after their publication, it is unknown whether the recommendations have led to changes in primary care practice patterns. Objectives: To determine whether HTN guidelines are associated with changes in practice patterns among primary care clinicians. Design, Setting, and Participants: This retrospective, multicenter, population-based cohort study was conducted across 3 phases: January 1, 2011, to December 31, 2015 (era 1), January 1, 2016, to December 31, 2017 (washout period), and January 1, 2018, to December 31, 2019 (era 2). Data were collected from 7 Canadian provinces using the Canadian Primary Care Sentinel Surveillance Network Electronic Medical Record database. Eligible participants included children and adolescents (aged ≥3 to <18 years) with 1 or more encounters in the database. Data analysis was conducted from February 2022 to February 2023. Exposure: Implementation of the 2016 Hypertension Canada and 2017 American Academy of Pediatrics guidelines. Main Outcomes and Measures: The primary outcomes were annual BP screening documentation, high BP follow-up documentation at 6 months and 1-year, HTN prevalence, laboratory testing rates, and medication prescription rates. Interrupted time series analysis was used to assess the association of the introduction of the Canadian and US guidelines with outcomes. Results: The study included 343 191 children and adolescents (mean [SD] age at first encounter, 6.7 (4.6) years; 173 290 female [50.5%]; 169 901 male [49.5%]), including 235 094 patients in era 1 and 193 473 patients in era 2. In era 1, 55 550 patients (23.6%) had at least 1 BP measurement, and in era 2, 45 006 patients (23.3%) had at least 1 BP measurement. There was a significant increase in BP screening in era 2 from 26 876 of 148 554 screenings (18.1%) to 28 556 of 141 192 screenings (20.2%; ß = 0.202; 95% CI, 0.009 to 0.390; P = .04), and the increasing trend was sustained. There was a significant decrease in the trend of follow-up of high BP measurement at 6 months (1265 of 4941 patients with BP measurements [25.6%] to 1718 of 7321 patients with BP measurements [23.5%]; ß = -0.490; 95% CI, -0.758 to -0.223; P = .001) and 1 year (1974 of 4941 measurements [40.0%] to 2314 of 7321 measurements [31.6%]; ß = -1.392; 95% CI, -1.573 to -1.212; P < .001) in era 2. The proportion of patients meeting HTN criteria significantly increased from 2540 of 55 550 patients (4.6%) in era 1 to 5690 of 45 006 patients (12.6%) in era 2 (ß = 0.0210; 95% CI, 0.0021 to 0.0410; P = .03). There was no significant change in the trend of laboratory testing rates in era 2 (949 of 4941 patients tested [19.2%] to 1149 of 7321 patients tested [15.7%]; ß = -0.159; 95% CI, -0.364 to 0.046; P = .12). The trend in prescribing of medications to patients with HTN also decreased in era 2 (1305 of 4941 patients prescribed medication [26.4%] to 1415 of 7321 patients prescribed medication [19.3%]; ß = -0.605; 95% CI, -0.830 to -0.358; P < .001). Conclusions and Relevance: The findings of this cohort study within the Canadian primary care setting suggest that there was a significant increase in BP screening and HTN prevalence after the publication of national and international HTN guidelines; however, the follow-up of high BP was still suboptimal. Increasing rates of pediatric HTN emphasize the need for better adherence to pediatric HTN guidelines to improve care and outcomes.

Evaluation of Expanded 2-Aminobenzothiazole Library for Inhibition of Pseudomonas aeruginosa Virulence Phenotypes.

Bacterial resistance to antibiotics is a rapidly increasing threat to human health. New strategies to combat resistant organisms are desperately needed. One potential avenue is targeting two-component systems, which are the main bacterial signal transduction pathways used to regulate development, metabolism, virulence, and antibiotic resistance. These systems consist of a homodimeric membrane-bound sensor histidine kinase, and a cognate effector, the response regulator. The high sequence conservation in the catalytic and adenosine triphosphate-binding (CA) domain of histidine kinases and their essential role in bacterial signal transduction could enable broad-spectrum antibacterial activity. Through this signal transduction, histidine kinases regulate multiple virulence mechanisms including toxin production, immune evasion, and antibiotic resistance. Targeting virulence, as opposed to development of bactericidal compounds, could reduce evolutionary pressure for acquired resistance. Additionally, compounds targeting the CA domain have the potential to impair multiple two-component systems that regulate virulence in one or more pathogens. We conducted structure-activity relationship studies of 2-aminobenzothiazole-based inhibitors designed to target the CA domain of histidine kinases. We found these compounds have anti-virulence activities in Pseudomonas aeruginosa, reducing motility phenotypes and toxin production associated with the pathogenic functions of this bacterium.

Predictors of multiple dilations and functional outcomes after total laryngectomy and laryngopharyngectomy.

BACKGROUND: Following total laryngectomy (TL) or laryngopharyngectomy (TLP), patients may develop strictures that require multiple dilations to treat. However, the risk factors associated with dysphagia refractory to a single dilation are unknown. METHODS: Single-institution retrospective review of patients who underwent at least one stricture dilation after TL/TLP between March 2013 and March 2022. RESULTS: A total of 49 patients underwent stricture dilation after TL/TLP. Thirty-five (71%) underwent multiple dilations. Pharyngocutaneous fistula, primary chemoradiation therapy, and a shorter time interval from TL/TLP to first dilation were independently associated with dysphagia requiring multiple dilations. Patients in the multiple dilations group had a higher rate of limited diet and G-tube dependence compared to patients in the single dilation group. CONCLUSIONS: Shorter time interval to stricture formation is a prognostic indicator of the need for multiple dilations following TL/TLP. Patients requiring multiple dilations are at increased risk of persistent dysphagia long-term.

Early Weight-Bearing After Fibula Free Flap Surgery.

Importance: Despite the widespread use of fibula free flap (FFF) surgery for head and neck reconstruction, there are no studies assessing if early weight-bearing (EWB) affects postoperative recovery, and the timing of weight-bearing initiation following FFF surgery varies considerably across institutions. Therefore, it is important to understand the effect of EWB in these patients and whether it could improve postoperative recovery. Objective: To assess the association of EWB after FFF surgery with donor-site complications, length of stay, and discharge to home status. Design, Setting, and Participants: This retrospective cohort study took place at Massachusetts Eye and Ear, a single tertiary care institution in Boston, Massachusetts. A total of 152 patients who received head and neck reconstruction with a fibula osteocutaneous free flap between January 11, 2010, and August 11, 2022, were included. Exposure: EWB on postoperative day 1 vs non-EWB on postoperative day 2 or later. Main Outcomes and Measures: Patient characteristics, including demographic characteristics and comorbidities, surgical characteristics, donor-site complications, length of stay, and discharge disposition, were recorded. Descriptive statistics and multivariate logistic regressions were used to compute effect sizes and 95% CIs to compare postoperative outcomes in EWB and non-EWB groups. Results: A total of 152 patients (median [IQR] age, 63 [55-70] years; 89 [58.6%] male) were included. The median (IQR) time to postoperative weight-bearing was 3 (1-5) days. Among all patients, 14 (9.2%) had donor-site complications. EWB on postoperative day 1 was associated with shorter length of stay (adjusted odds ratio [AOR], 0.10; 95% CI, 0.02-0.60), increased rate of discharge to home (AOR, 7.43; 95% CI, 2.23-24.80), and decreased donor-site complications (AOR, 0.11; 95% CI, 0.01-0.94). Conversely, weight-bearing 3 or more days postoperatively was associated with an increased risk of pneumonia (AOR, 6.82; 95% CI, 1.33-34.99). Conclusions and Relevance: In this cohort study, EWB after FFF surgery was associated with shorter length of stay, increased rate of discharge to home, and decreased donor-site complications. These findings support the role of early mobilization to optimize postoperative recovery after FFF surgery.

Applications of Advanced Natural Language Processing for Clinical Pharmacology.

Natural language processing (NLP) is a branch of artificial intelligence, which combines computational linguistics, machine learning, and deep learning models to process human language. Although there is a surge in NLP usage across various industries in recent years, NLP has not been widely evaluated and utilized to support drug development. To demonstrate how advanced NLP can expedite the extraction and analyses of information to help address clinical pharmacology questions, inform clinical trial designs, and support drug development, three use cases are described in this article: (1) dose optimization strategy in oncology, (2) common covariates on pharmacokinetic (PK) parameters in oncology, and (3) physiologically-based PK (PBPK) analyses for regulatory review and product label. The NLP workflow includes (1) preparation of source files, (2) NLP model building, and (3) automation of data extraction. The Clinical Pharmacology and Biopharmaceutics Summary Basis of Approval (SBA) documents, US package inserts (USPI), and approval letters from the US Food and Drug Administration (FDA) were used as our source data. As demonstrated in the three example use cases, advanced NLP can expedite the extraction and analyses of large amounts of information from regulatory review documents to help address important clinical pharmacology questions. Although this has not been adopted widely, integrating advanced NLP into the clinical pharmacology workflow can increase efficiency in extracting impactful information to advance drug development.

Characteristics and Clinical Outcomes of Vaccine-Eligible US Children Under-5 Years Hospitalized for Acute COVID-19 in a National Network.

BACKGROUND AND OBJECTIVES: In June 2022, the mRNA COVID-19 vaccination was recommended for young children. We examined clinical characteristics and factors associated with vaccination status among vaccine-eligible young children hospitalized for acute COVID-19. METHODS: We enrolled inpatients 8 months to <5 years of age with acute community-acquired COVID-19 across 28 US pediatric hospitals from September 20, 2022 to May 31, 2023. We assessed demographic and clinical factors, including the highest level of respiratory support, and vaccination status defined as unvaccinated, incomplete, or complete primary series [at least 2 (Moderna) or 3 (Pfizer-BioNTech) mRNA vaccine doses ≥14 days before hospitalization]. RESULTS: Among 597 children, 174 (29.1%) patients were admitted to the intensive care unit and 75 (12.6%) had a life-threatening illness, including 51 (8.5%) requiring invasive mechanical ventilation. Children with underlying respiratory and neurologic/neuromuscular conditions more frequently received higher respiratory support. Only 4.5% of children hospitalized for COVID-19 (n = 27) had completed their primary COVID-19 vaccination series and 7.0% (n = 42) of children initiated but did not complete their primary series. Among 528 unvaccinated children, nearly half (n = 251) were previously healthy, 3 of them required extracorporeal membrane oxygenation for acute COVID-19 and 1 died. CONCLUSIONS: Most young children hospitalized for acute COVID-19, including most children admitted to the intensive care unit and with life-threatening illness, had not initiated COVID-19 vaccination despite being eligible. Nearly half of these children had no underlying conditions. Of the small percentage of children who initiated a COVID-19 primary series, most had not completed it before hospitalization.

Observational study to understand the effect of timing and regularity on sleep metrics and cardiorespiratory parameters using data from a smart bed.

Sleep regularity and chronotype can affect health, performance, and overall well-being. This observational study examines how sleep regularity and chronotype affect sleep quality and cardiorespiratory metrics. Data was collected from 1 January 2019 through 30 December 2019 from over 330 000 Sleep Number smart bed users across the United States who opted into this at-home study. A pressure signal from the smart bed reflected bed presence, movements, heart rate (HR), and breathing rate (BR). Participants (mean age: 55.69 years [SD: 14.0]; 51.2% female) were categorized by chronotype (16.8% early; 62.2% intermediate, 20.9% late) and regularity of sleep timing. Participants who were regular sleepers (66.1%) experienced higher percent restful sleep and lower mean HR and BR compared to the 4.8% categorized as irregular sleepers. Regular early-chronotype participants displayed better sleep and cardiorespiratory parameters compared to those with regular late-chronotypes. Significant variations were noted in sleep duration (Cohen's d = 1.54 and 0.88, respectively) and restful sleep (Cohen's d = 1.46 and 0.82, respectively) between early and late chronotypes, particularly within regular and irregular sleep patterns. This study highlights how sleep regularity and chronotype influence sleep quality and cardiorespiratory metrics. Irrespective of chronotype, sleep regularity demonstrated a substantial effect. Further research is necessary to confirm these findings.

Severe Pediatric Open Skull Fracture With Exposed Brain Matter: A Case Report.

Head trauma in the pediatric population carries a high rate of morbidity and mortality. The major causes of head trauma are related to falls, recreational activities, motor vehicle accidents, and gunshot wounds. Traumatic brain injury (TBI) can occur after severe head trauma and is defined as an alteration in brain function, or other evidence of brain pathology, caused by an external force. Intracranial edema and herniation are common consequences of a TBI in pediatric patients and are commonly relieved via decompressive craniectomy.  This case study describes a 13-year-old male presenting to the trauma center after an unhelmeted all-terrain vehicle (ATV) accident with a positive head strike and loss of consciousness. The evaluation revealed extensive skull fractures extending from the frontal to the occipital lobe with brain exposure. Computed tomography (CT) scan of the head demonstrated extensive, open skull fractures with significant displacement of the exposed brain, extensive bilateral parietal and frontal bone fractures, and bilateral temporal bone displaced fractures more extensive on the left. A bilateral hemicraniectomy was performed due to diffuse cerebral edema and a left frontal ventriculostomy was placed to monitor and manage intracranial pressure (ICP). It is believed that the unique presentation of an open skull fracture with an exposed brain acted as a decompressive method allowing for extreme lifesaving measures to be performed to save the patient. Further exploration is needed to truly understand the effects of the unique injury presentation and the role of an open fracture in the delay of increased ICP.

Limitation of permutation-based differential correlation analysis.

The comparison of biological systems, through the analysis of molecular changes under different conditions, has played a crucial role in the progress of modern biological science. Specifically, differential correlation analysis (DCA) has been employed to determine whether relationships between genomic features differ across conditions or outcomes. Because ascertaining the null distribution of test statistics to capture variations in correlation is challenging, several DCA methods utilize permutation which can loosen parametric (e.g., normality) assumptions. However, permutation is often problematic for DCA due to violating the assumption that samples are exchangeable under the null. Here, we examine the limitations of permutation-based DCA and investigate instances where the permutation-based DCA exhibits poor performance. Experimental results show that the permutation-based DCA often fails to control the type I error under the null hypothesis of equal correlation structures.

How do network meta-analyses address intransitivity when assessing certainty of evidence: a systematic survey.

OBJECTIVES: To describe how systematic reviews with network meta-analyses (NMAs) that used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) NMA approach addressed intransitivity when assessing certainty of evidence. DESIGN: Systematic survey. DATA SOURCES: Medline, Embase and Cochrane Database of Systematic Reviews from September 2014 to October 2022. ELIGIBILITY CRITERIA: Systematic reviews of randomised controlled trials with aggregate data NMAs that used the GRADE NMA approach for assessing certainty of evidence. DATA EXTRACTION AND SYNTHESIS: We documented how reviewers described methods for addressing intransitivity when assessing certainty of evidence, how often they rated down for intransitivity and their explanations for rating down. RESULTS: Of the 268 eligible systematic reviews, 44.8% (120/268) mentioned intransitivity when describing methods for assessing the certainty of evidence. Of these, 28.3% (34/120) considered effect modifiers and from this subset, 67.6% (23/34) specified the effect modifiers; however, no systematic review noted how they chose the effect modifiers. 15.0% (18/120) mentioned looking for differences between the direct comparisons that inform the indirect estimate. No review specified a threshold for difference in effect modifiers between the direct comparisons that would lead to rating down for intransitivity. Reviewers noted rating down indirect evidence for intransitivity in 33.1% of systematic reviews, and noted intransitivity for network estimates in 23.0% of reviews. Authors provided an explanation for rating down for intransitivity in 59.6% (31/52) of the cases in which they rated down. Of the 31 in which they provided an explanation, 74.2% (23/31) noted they detected differences in effect modifiers and 67.7% (21/31) specified in what effect modifiers they detected differences. CONCLUSIONS: A third of systematic reviews with NMAs using the GRADE approach rated down for intransitivity. Limitations in reporting of methods to address intransitivity proved considerable. Whether the problem is that reviewers neglected to address rating down for transitivity at all, or whether they did consider but not report, is not clear. At minimum systematic reviews with NMAs need to improve their reporting practices regarding intransitivity; it may well be that they need to improve their practice in transitivity assessment. How to best address intransitivity may remain unclear for many reviewers thus additional GRADE guidance providing practical instructions for addressing intransitivity may be desirable.

Real-life Clinical Outcomes of Low-voltage Isolation and Spatiotemporal Dispersion Ablation Strategies for Persistent Atrial Fibrillation.

Multiple techniques have been developed in addition to pulmonary vein isolation (PVI) to improve the outcomes of catheter ablation in patients with persistent atrial fibrillation (AF). We sought to evaluate the long-term efficacy of alternative techniques used in our laboratory for the treatment of persistent AF, including spatiotemporal dispersion (SD) and low-voltage isolation (LVI). Consecutive patients with persistent AF who underwent catheter ablation with the studied techniques between July 2016 and December 2019 were included in the study. PVI alone was compared with PVI plus SD and PVI plus LVI in terms of long-term freedom from atrial tachycardia (AT) and AF recurrence. Follow-up data were obtained from clinical records and hospital visits, which included a 7-day Holter monitor and electrocardiograms. The study was approved by the institutional review board of Rhode Island Hospital. A total of 382 patients underwent catheter ablation at our institution during the study period. One hundred seventy-two patients had paroxysmal AF and were excluded from the study. The remaining 210 patients had persistent AF and were included in the study. One hundred and three patients underwent PVI alone, while 48 had the addition of LVI and 59 had SD. Additionally, freedom from AT/AF recurrence at 18 months was 68% in the group that underwent LVI, 49% in the SD group, and 40% in the group that underwent PVI alone (log-rank P = .014). Freedom from AF recurrence was 74% in the LVI group, 71% in the SD group, and 43% in the PVI-alone group (log-rank P = .002). On multivariate Cox regression, LVI and left atrial size were found to be independent predictors of recurrence (hazard ratio, 0.39; 95% confidence interval, 0.206-0.760; P = .005 and hazard ratio, 1.4; 95% confidence interval, 1.105-1.923; P = .008, respectively). LVI and SD in addition to PVI were associated with greater freedom from AT/AF recurrence at 18 months compared to PVI alone.