Markov Blankets and Mirror Symmetries-Free Energy Minimization and Mesocortical Anatomy.

A theoretical account of development in mesocortical anatomy is derived from the free energy principle, operating in a neural field with both Hebbian and anti-Hebbian neural plasticity. An elementary structural unit is proposed, in which synaptic connections at mesoscale are arranged in paired patterns with mirror symmetry. Exchanges of synaptic flux in each pattern form coupled spatial eigenmodes, and the line of mirror reflection between the paired patterns operates as a Markov blanket, so that prediction errors in exchanges between the pairs are minimized. The theoretical analysis is then compared to the outcomes from a biological model of neocortical development, in which neuron precursors are selected by apoptosis for cell body and synaptic connections maximizing synchrony and also minimizing axonal length. It is shown that this model results in patterns of connection with the anticipated mirror symmetries, at micro-, meso- and inter-arial scales, among lateral connections, and in cortical depth. This explains the spatial organization and functional significance of neuron response preferences, and is compatible with the structural form of both columnar and noncolumnar cortex. Multi-way interactions of mirrored representations can provide a preliminary anatomically realistic model of cortical information processing.

Dose selection for aztreonam-avibactam, including adjustments for renal impairment, for Phase IIa and Phase III evaluation.

PURPOSE: A series of iterative population pharmacokinetic (PK) modeling and probability of target attainment (PTA) analyses based on emerging data supported dose selection for aztreonam-avibactam, an investigational combination antibiotic for serious Gram-negative bacterial infections. METHODS: Two iterations of PK models built from avibactam data in infected patients and aztreonam data in healthy subjects with "patient-like" assumptions were used in joint PTA analyses (primary target: aztreonam 60% fT > 8 mg/L, avibactam 50% fT > 2.5 mg/L) exploring patient variability, infusion durations, and adjustments for moderate (estimated creatinine clearance [CrCL] > 30 to ≤ 50 mL/min) and severe renal impairment (> 15 to ≤ 30 mL/min). Achievement of > 90% joint PTA and the impact of differential renal clearance were considerations in dose selection. RESULTS: Iteration 1 simulations for Phase I/IIa dose selection/modification demonstrated that 3-h and continuous infusions provide comparable PTA; avibactam dose drives joint PTA within clinically relevant exposure targets; and loading doses support more rapid joint target attainment. An aztreonam/avibactam 500/137 mg 30-min loading dose and 1500/410 mg 3-h maintenance infusions q6h were selected for further evaluation. Iteration 2 simulations using expanded PK models supported an alteration to the regimen (500/167 mg loading; 1500/500 mg q6h maintenance 3-h infusions for CrCL > 50 mL/min) and selection of doses for renal impairment for Phase IIa/III clinical studies. CONCLUSION: A loading dose plus 3-h maintenance infusions of aztreonam-avibactam in a 3:1 fixed ratio q6h optimizes joint PTA. These analyses supported dose selection for the aztreonam-avibactam Phase III clinical program. CLINICAL TRIAL REGISTRATION: NCT01689207; NCT02655419; NCT03329092; NCT03580044.

Methodological review of NMA bias concepts provides groundwork for the development of a list of concepts for potential inclusion in a new risk of bias tool for network meta-analysis (RoB NMA Tool).

INTRODUCTION: Network meta-analyses (NMAs) have gained popularity and grown in number due to their ability to provide estimates of the comparative effectiveness of multiple treatments for the same condition. The aim of this study is to conduct a methodological review to compile a preliminary list of concepts related to bias in NMAs. METHODS AND ANALYSIS: We included papers that present items related to bias, reporting or methodological quality, papers assessing the quality of NMAs, or method papers. We searched MEDLINE, the Cochrane Library and unpublished literature (up to July 2020). We extracted items related to bias in NMAs. An item was excluded if it related to general systematic review quality or bias and was included in currently available tools such as ROBIS or AMSTAR 2. We reworded items, typically structured as questions, into concepts (i.e. general notions). RESULTS: One hundred eighty-one articles were assessed in full text and 58 were included. Of these articles, 12 were tools, checklists or journal standards; 13 were guidance documents for NMAs; 27 were studies related to bias or NMA methods; and 6 were papers assessing the quality of NMAs. These studies yielded 99 items of which the majority related to general systematic review quality and biases and were therefore excluded. The 22 items we included were reworded into concepts specific to bias in NMAs. CONCLUSIONS: A list of 22 concepts was included. This list is not intended to be used to assess biases in NMAs, but to inform the development of items to be included in our tool.

HIGHLIGHTS: • Our research aimed to develop a preliminary list of concepts related to bias with the goal of developing the first tool for assessing the risk of bias in the results and conclusions of a network meta-analysis (NMA).• We followed the methodology proposed by Whiting (2017) and Sanderson (2007) for creating systematically developed lists of quality items, as a first step in the development of a risk of bias tool for network meta-analysis (RoB NMA Tool).• We included items related to biases in NMAs and excluded items that are equally applicable to all systematic reviews as they are covered by other tools (e.g. ROBIS, AMSTAR 2).• Fifty-seven studies were included generating 99 items, which when screened, yielded 22 included items. These items were then reworded into concepts in preparation for a Delphi process for further vetting by external experts.• A limitation of our study is the challenge in retrieving methods studies as methods collections are not regularly updated.

Protocol for Surgery or Cast of the EpicoNdyle in Children's Elbows (SCIENCE).

Aims: The management of fractures of the medial epicondyle is one of the greatest controversies in paediatric fracture care, with uncertainty concerning the need for surgery. The British Society of Children's Orthopaedic Surgery prioritized this as their most important research question in paediatric trauma. This is the protocol for a randomized controlled, multicentre, prospective superiority trial of operative fixation versus nonoperative treatment for displaced medial epicondyle fractures: the Surgery or Cast of the EpicoNdyle in Children's Elbows (SCIENCE) trial. Methods: Children aged seven to 15 years old inclusive, who have sustained a displaced fracture of the medial epicondyle, are eligible to take part. Baseline function using the Patient-Reported Outcomes Measurement Information System (PROMIS) upper limb score, pain measured using the Wong Baker FACES pain scale, and quality of life (QoL) assessed with the EuroQol five-dimension questionnaire for younger patients (EQ-5D-Y) will be collected. Each patient will be randomly allocated (1:1, stratified using a minimization algorithm by centre and initial elbow dislocation status (i.e. dislocated or not-dislocated at presentation to the emergency department)) to either a regimen of the operative fixation or non-surgical treatment. Outcomes: At six weeks, and three, six, and 12 months, data on function, pain, sports/music participation, QoL, immobilization, and analgesia will be collected. These will also be repeated annually until the child reaches the age of 16 years. Four weeks after injury, the main outcomes plus data on complications, resource use, and school absence will be collected. The primary outcome is the PROMIS upper limb score at 12 months post-randomization. All data will be obtained through electronic questionnaires completed by the participants and/or parents/guardians. The NHS number of participants will be stored to enable future data linkage to sources of routinely collected data (i.e. Hospital Episode Statistics).

Contrasting reactivity of B-Cl and B-H bonds at [Ni(IMes)2] to form unsupported Ni-boryls.

[Ni(IMes)2] reacts with chloroboranes via oxidative addition to form rare unsupported Ni-boryls. In contrast, the oxidative addition of hydridoboranes is not observed and products from competing reaction pathways are identified. Computational studies relate these differences to the mechanism of oxidative addition: B-Cl activation proceeds via nucleophilic displacement of Cl-, while B-H activation would entail high energy concerted bond cleavage.

Surgeon Experience Is the Most Important Predictor of Case Failure Rate for Anterior Odontoid Screw Fixation: A Large Database Study.

STUDY DESIGN: Retrospective database analysis. OBJECTIVE: Determine risk factors and failure rate of anterior odontoid screw fixation surgery. SUMMARY OF BACKGROUND DATA: Anterior odontoid screw fixation (AOSF) stabilizes type II dens fractures while preserving cervical motion. Despite having potential advantages, AOSF's failure rate and factors contributing to failure remain unknown. MATERIALS AND METHODS: We identified AOSF patients in the national claims database Pearldiver using CPT code 22318. Failure was defined as the requirement of supplementary posterior fusion surgery in the C1-C2 or occiput-C2 region after the AOSF. We considered potential predictors of failure including age, sex, Charlson Comorbidity Index (CCI), surgeon experience, history of osteoporosis, obesity, and tobacco use. Univariate comparison analysis and logistic regression were conducted to identify factors associated with the need for additional posterior surgery. RESULTS: For 2008 identified cases of AOSF, 249 cases (12.4%) required additional posterior fusion. Seventy-one of the 249 cases (28.5%) underwent revision surgery on the same day as the AOSF. Over 86% of revisions (215 cases) occurred within 200 days of the initial procedure. Posterior fusion rates are inversely correlated with surgeon experience, with the most experienced surgeons having a rate of 10.0%, followed by 11.5% for moderately experienced surgeons, and 15.0% for the least experienced surgeons. When comparing moderate and inexperienced surgeons to experienced surgeons, the odds ratios for posterior fusion were 1.18 (P>0.05) and 1.61 (P<0.006), respectively. Logistic regression revealed that both lesser experience (odds ratio=1.50) and osteoporosis (odds ratio=1.44) were the only factors significantly associated with failure (P<0.05). CONCLUSIONS: Our findings indicate a correlation between AOSF success and surgeon experience. While currently published results suggest higher success rates, most of this data originates from experienced surgeons and specialized centers, therefore, they may not accurately reflect the failure rate encountered in a more general practice setting. LEVEL OF EVIDENCE: Level III.

Atmospheric solids analysis probe mass spectrometry: An easy bolt-on for the synthetic undergraduate teaching laboratory.

RATIONALE: High costs and student numbers can often hinder implementation of mass spectrometry (MS) in the undergraduate teaching laboratory, often with technicians running samples on students' behalf, and the implementation of MS only in discrete or isolated experiments. This study explores the use of atmospheric solids analysis probe MS (ASAP-MS) as a relatively low-cost, benchtop instrument, and its potential for application as a 'bolt-on' to existing undergraduate organic chemistry experiments. METHODS: Thirteen products synthesised in undergraduate laboratory experiments were analysed by ASAP-MS, along with their starting materials. Analysis was carried out with a Waters RADIAN ASAP mass spectrometer, at four different cone voltages simultaneously to provide fragmentation information. RESULTS: Out of the 13 undergraduate experiments, ASAP-MS was shown to be complementary in 11 of these, either through simple analysis of the precursor ion or by a more complex analysis of the fragments. CONCLUSIONS: ASAP-MS provided spectra that both complement and enhance intended learning outcomes in existing organic chemistry experiments, showing its versatility as a bolt-on technique. Moving forward, ASAP-MS will be integrated into the University of Surrey's undergraduate teaching laboratory.

Characterizing utilization patterns and reoperation risk factors of interspinous process devices: analysis of a national claims database.

INTRODUCTION: Interspinous process devices (IPDs) were developed as minimally invasive alternatives to open decompression surgery for spinal stenosis. However, given high treatment failure and reoperation rates, there has been minimal adoption by spine surgeons. This study leveraged a national claims database to characterize national IPD usage patterns and postoperative outcomes after IPD implantation. METHOD: Using the PearlDiver database, we identified all patients who underwent 1- or 2-level IPD implantation between 2010 and 2018. Univariate and multivariable logistic regression was performed to identify predictors of the number of IPD levels implanted and reoperation up to 3 years after the index surgery. Right-censored Kaplan-Meier curves were plotted for duration of reoperation-free survival and compared with log-rank tests. RESULTS: Patients (n = 4865) received 1-level (n = 3246) or 2-level (n = 1619) IPDs. Patients who were older (adjusted odds ratio [aOR] 1.02, 95% confidence interval [CI] 1.01-1.03, P < .001), male (aOR 1.31, 95% CI 116-1.50, P < .001), and obese (aOR 1.19, 95% CI 1.05-1.36, P < .01) were significantly more likely to receive a 2-level IPD than to receive a 1-level IPD. The 3-year reoperation rate was 9.3% of patients when mortality was accounted for during the follow-up period. Older age decreased (aOR 0.97, 95% CI 0.97-0.99, P = .0039) likelihood of reoperation, whereas 1-level IPD (aOR 1.37, 95% CI 1.01-1.89, P = .048), Charlson Comorbidity Index (aOR 1.07, 95% CI 1.01-1.14, P = .018), and performing concomitant open decompression increased the likelihood of reoperation (aOR 1.68, 95% CI 1.35-2.09, P = .0014). CONCLUSION: Compared with 1-level IPDs, 2-level IPDs were implanted more frequently in older, male, and obese patients. The 3-year reoperation rate was 9.3%. Concomitant open decompression with IPD placement was identified as a significant risk factor for subsequent reoperation and warrants future investigation.

Inappropriate Use of Proton Pump Inhibitor Among Elderly Patients in British Columbia: What are the Long-term Adverse Events?

BACKGROUND: Proton pump inhibitors (PPIs) are one of the most used classes of drugs. For most indications, PPIs are only recommended up to 8 weeks duration. However, PPI use continues to expand. Regular and prolonged use of PPIs should be avoided because of the risk of adverse events. OBJECTIVES: The main objective of this study was to (1) investigate the extent of PPI usage in people aged 65 or older in the province of British Columbia (BC), Canada, (2) provide an overview of the harms associated with the long-term use of PPIs. METHODS: We examined utilization trends of the PPIs in BC since the year 2009 using PharmaNet, BC's medication dispensing database where the information is accessible to community pharmacists. We performed a comprehensive literature search for relevant reviews reporting harms associated with long-term use of PPIs. A search was conducted from January 2014 to June 2022. RESULTS: Between 2000 and 2018 BC's population grew by 20%, but the use of PPIs escalated to 257%. Of these older British Columbians, 62% had a cumulative exposure exceeding 2 years and 42% exceeded 5 years. This is alarming because the recommended treatment duration is 4-12 weeks for common indications including reflux esophagitis, and duodenal and gastric ulcers. Only 13.5% were dispensed PPIs for 90 days or less. Patients on long-term PPI therapy should be reassessed. Adverse events of PPI use are common among older adults. We identified over 217 systematic reviews published during the last 8 years of specific harms associated with long-term daily usage of PPIs. These harms include increased risks of death, cardiovascular disease, acute renal injury, chronic kidney disease, dementia, fractures, hypomagnesemia, iron deficiency, vitamin B12 deficiency, enteric infection (including C. difficile), pneumonia, and neoplasia (gastric cancer, carcinoids, and colon cancer), and drug interactions. CONCLUSION: This study revealed a high prevalence of PPI use among elderly populations in BC, Canada. The overutilization of PPIs is often a result of failure to re-evaluate the need for continuation of therapy. Published studies identified signals of serious harm from long-term PPI exposure. Healthcare providers with patients can reverse the relentless expansion of long-term PPI exposure by discussing the expected benefits and potential harms.

Lydia Marie DeWitt and Mary Butler Kirkbride: Prototypical Circa-Early-1900s Women of Pathology and an Analysis of Their Contributions to the Discovery of Insulin.

CONTEXT.­: The year 2023 marks the centenary of the Nobel Prize honoring the discovery of insulin. Little-known experimental pathologists Lydia DeWitt, MD, at the University of Michigan and Mary Kirkbride, DSc [Hon], at Columbia University, both just beginning their academic careers, made independent contributions to the discovery that have never been critically examined. This happened at a time when it was exceedingly rare for women to work in pathology. OBJECTIVE.­: To explore the facilitative roles of DeWitt and Kirkbride in the discovery of insulin and to examine their trail-breaking careers in academic pathology. DESIGN.­: Available primary and secondary historical resources were reviewed. RESULTS.­: DeWitt made and tested pancreatic extracts from duct-ligated atrophic pancreas (ie, Frederick Banting's great idea to prevent digestion of its hypothetical internal secretion) 15 years before Banting; Banting was unaware of her work. His idea came from reading a paper by pathologist Moses Barron. Prior duct-ligation studies had sometimes been viewed with skepticism because histologic identification of islets in atrophic duct-ligated pancreata was imperfect; Kirkbride addressed this with histochemical staining, convincing Barron and, therefore, indirectly influencing and motivating Banting. The lives and convoluted careers of these 2 early-20th-century women are explored and compared with those of other contemporary women in pathology. A unifying pattern becomes clear: careers in experimental pathology and bacteriology were accepted but performing clinical work in anatomic pathology was not. CONCLUSIONS.­: Both DeWitt and Kirkbride are prototypical early-20th-century women in academic pathology whose careers were constrained by gender. However, Kirkbride made a unique and unrecognized contribution to the discovery of insulin.

Maud Menten: Pioneering Pediatric-Perinatal Pathologist, Clinician-Scientist, and "the Most Wonderful Human Being in the World".

Maud Menten was born and raised in remote regions of Canada. She obtained her MB/MD at the University of Toronto (1907/1911) and her PhD in biochemistry at the University of Chicago (1916). From 1907 to 1916, she trained at the Rockefeller Institute for Medical Research, the New York Infirmary for Women and Children, Western Reserve University in Cleveland, the Berlin Municipal Hospital in Germany, and the Barnard Free Skin and Cancer Hospital in St Louis. In 1916, she was appointed as pathologist at the Elizabeth Steel Magee Hospital, a charitable maternity hospital in Pittsburgh. She received a faculty appointment at the University of Pittsburgh (1918) and was appointed pathologist at Pittsburgh Children's Hospital (1926). In addition to being one of the first woman academic pathologists, she was likely the first perinatal, the second pediatric-perinatal, and the fourth pediatric pathologist to practice in North America. The importance of Menten's overall scientific contributions place her in the very upper echelon of 20th century pathologists. Her enzyme kinetic work resulted in the Michaelis-Menten equation, and her work in George Crile's laboratory in Cleveland provided a physiological basis for improved surgical outcomes. Her work in Pittsburgh was equally innovative, including initiating the field of enzyme histochemistry.

Dick van Velzen and the Burnside warehouse organ scandal in Nova Scotia, Canada.

Dick van Velzen practiced as a pediatric pathologist at Alder Hey Children's Hospital in Liverpool, England from September 1988 until December 1995; he then relocated to the IWK-Grace Health Centre, a children's and maternity hospital in Halifax, Nova Scotia, Canada, where he practiced until he was fired for cause in January 1998. About a year and a half later, his practice in Liverpool came under increasing scrutiny, with the initial focus on the massive collection of post-mortem pediatric organs he had accumulated for planned future research on sudden infant death syndrome. Soon, a Parliamentary Inquiry began investigating the full scope of his Liverpool practice. During the Inquiry, another organ-hoarding scandal erupted; van Velzen, when leaving Halifax after his dismissal, had put his family's personal belongings into a storage facility at Burnside Industrial Park and then did not pay bills. As his belongings were being prepared for auction, formalin-fixed organs were found, and a Canada-wide arrest warrant for disrespect for human remains was issued by the Halifax Police. While the Alder Hey scandal resulted in a 535-page-long Parliamentary Report and the Human Tissue Act, van Velzen was never charged criminally in the UK. The largely unknown story of his second organ scandal in Halifax, is related here. Although he had obtained the body parts with the consent of the parents of the child to which they had belonged, his failure to properly identify and store them traumatized parents already impacted by his organ-hoarding in the UK, traumatized additional parents in Halifax, and resulted in significant waste of public resources in investigating the case. He pled guilty to "indignity to a human body" in Canada and was fined and placed on 12 months' probation.

Cost-effectiveness of a novel urethral catheter safety device in preventing catheterization injuries in the UK.

AIMS: Intraurethral catheter balloon inflation is a substantial contributor to significant catheter-related urethral injury. A novel safety valve has been designed to prevent these balloon-inflation injuries. The purpose of this evaluation was to assess the cost-effectiveness of urethral catheterisation with the safety valve added to a Foley catheter versus the current standard of care (Foley catheter alone). MATERIALS AND METHODS: The analysis was conducted from the UK public payer perspective on a hypothetical cohort of adults requiring transurethral catheterization. A decision tree was used to capture outcomes in the first 30 days following transurethral catheterization, followed by a Markov model to estimate outcomes over a person's remaining lifetime. Clinical outcomes included catheter balloon injuries [CBIs], associated short-term complications, urethral stricture disease, life years and QALYs. Health-economic outcomes included total costs, incremental cost-effectiveness ratio, net monetary benefit (NMB) and net health benefit. RESULTS: Over a person's lifetime, the safety valve was predicted to reduce CBIs by 0.04 per person and CBI-related short-term complications by 0.03 per person, and nearly halve total costs. The safety valve was dominant, resulting in 0.02 QALYs gained and relative cost savings of £93.19 per person. Probabilistic sensitivity analysis indicated that the safety valve would be cost-saving in 97% of simulations run versus standard of care. CONCLUSIONS: The addition of a novel safety valve aiming to prevent CBIs during transurethral catheterization to current standard of care was estimated to bring both clinical benefits and cost savings.

Uptake of pertussis immunization in pregnancy and determinants of vaccination in Toronto, Canada.

INTRODUCTION: Pertussis causes significant morbidity and mortality in infants aged <6 months. Maternal pertussis vaccination during pregnancy has been recommended in Canada since 2018 to reduce these negative outcomes. In the absence of routine immunization coverage data, our objective was to evaluate uptake in Toronto, Canada. METHODS: We recruited mother-infant pairs at The Hospital for Sick Children, Toronto, between 2018 and 2020. We performed logistic regression to examine associations between demographics and self-reported pertussis vaccination. RESULTS: 76/243 mothers (31.3 %) reported receiving pertussis vaccination during their most recent pregnancy. Odds of receiving vaccination more than doubled with each 1-year increase in year of pregnancy (aOR: 2.2; 95 % CI: 1.3, 3.6; p < 0.01) and among those born in Canada as compared to those not (aOR: 2.0; 95 % CI: 1.1, 3.6; p = 0.02) CONCLUSION: Uptake of pertussis vaccination during pregnancy in Ontario has increased in recent years, however coverage remains lower than desirable.

The Essence in Selectivity of Copper-Mediated Intermolecular Nucleophilic Substitution of a meta C-H Bond in 2-Methyl-N-methoxyaniline: A Theoretical Study.

The detailed mechanism for NHC-Cu(I)-catalyzed intermolecular nucleophilic substitution of the C-H bonds at aniline (2-methyl-N-methoxyaniline) was studied via DFT methods to reveal the essence of the selectivity. Calculations revealed that the meta C-H functionalization proceeds via two nucleophilic attacks on the aromatic ring rather than a one-step meta C-H substitution to give the experimentally observed major product. The reaction is initiated by activation of the substrate via oxidative addition with an NHC-Cu(I) catalyst, through which an umpolung occurs at the ring. From the activated intermediate, methoxyl group transfer to benzyl forms a resting state, while a nucleophile can attack the ortho position of benzyl to form a more stable intermediate. The nucleophile group can then transfer to the meta position by a 1,2-Wagner-Meerwein rearrangement to form the final product through a proton shuttle. In contrast, other transfer processes affording ortho- or para-substituted products encounter higher activation barriers. This work investigates the relationship of product selectivity with the umpolung of the aromatic ring, as well as the priority of a nucleophilic attack at the ortho position of the aromatic, 1,2-Wagner-Meerwein rearrangement from the ortho-substituted intermediate, and proton shuttle from the meta-substituted intermediate.

Low body mass index patients have worse outcomes after mechanical thrombectomy.

BACKGROUND: There is evidence that frailty is an independent predictor of worse outcomes after stroke. Similarly, although obesity is associated with a higher risk for stroke, there are multiple reports describing improved mortality and functional outcomes in higher body mass index (BMI) patients in a phenomenon known as the obesity paradox. We investigated the effect of low BMI on outcomes after mechanical thrombectomy (MT). METHODS: We conducted a retrospective analysis of 231 stroke patients who underwent MT at an academic medical center between 2020-2022. The patients' BMI data were collected from admission records and coded based on the Centers for Disease Control and Prevention (CDC) obesity guidelines. Recursive partitioning analysis (RPA) in R software was employed to automatically detect a BMI threshold associated with a significant survival benefit. Frailty was quantified using the Modified Frailty Index 5 and 11. RESULTS: In our dataset, by CDC classification, 2.6% of patients were underweight, 27.3% were normal BMI, 30.7% were overweight, 19.9% were class I obese, 9.5% were class II obese, and 10% were class III obese. There were no significant differences between these groups. RPA identified a clinically significant BMI threshold of 23.62 kg/m2. Independent of frailty, patients with a BMI ≤23.62 kg/m2 had significantly worse overall survival (P<0.001) and 90-day modified Rankin Scale (P=0.027) than patients above the threshold. CONCLUSIONS: Underweight patients had worse survival and functional outcomes after MT. Further research should focus on the pathophysiology underlying poor prognosis in underweight MT patients, and whether optimizing nutritional status confers any neuroprotective benefit.

Pravastatin for lowering lipids.

BACKGROUND: A detailed summary and meta-analysis of the dose-related effect of pravastatin on lipids is not available. OBJECTIVES: Primary objective To assess the pharmacology of pravastatin by characterizing the dose-related effect and variability of the effect of pravastatin on the surrogate marker: low-density lipoprotein (LDL cholesterol). The effect of pravastatin on morbidity and mortality is not the objective of this systematic review. Secondary objectives • To assess the dose-related effect and variability of effect of pravastatin on the following surrogate markers: total cholesterol; high-density lipoprotein (HDL cholesterol); and triglycerides. • To assess the effect of pravastatin on withdrawals due to adverse effects. SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials (RCTs) up to September 2021: CENTRAL (2021, Issue 8), Ovid MEDLINE, Ovid Embase, Bireme LILACS, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. SELECTION CRITERIA: Randomized placebo-controlled trials evaluating the dose response of different fixed doses of pravastatin on blood lipids over a duration of three to 12 weeks in participants of any age with and without evidence of cardiovascular disease. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility criteria for studies to be included, and extracted data. We entered lipid data from placebo-controlled trials into Review Manager 5 as continuous data and withdrawal due to adverse effects (WDAEs) data as dichotomous data. We searched for WDAEs information from all trials. We assessed all trials using Cochrane's risk of bias tool under the categories of sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and other potential biases. MAIN RESULTS: Sixty-four RCTs evaluated the dose-related efficacy of pravastatin in 9771 participants. The participants were of any age, with and without evidence of cardiovascular disease, and pravastatin effects were studied within a treatment period of three to 12 weeks. Log dose-response data over the doses of 5 mg to 160 mg revealed strong linear dose-related effects on blood total cholesterol and LDL cholesterol, and a weak linear dose-related effect on blood triglycerides. There was no dose-related effect of pravastatin on blood HDL cholesterol. Pravastatin 10 mg/day to 80 mg/day reduced LDL cholesterol by 21.7% to 31.9%, total cholesterol by 16.1% to 23.3%,and triglycerides by 5.8% to 20.0%. The certainty of evidence for these effects was judged to be moderate to high. For every two-fold dose increase there was a 3.4% (95% confidence interval (CI) 2.2 to 4.6) decrease in blood LDL cholesterol. This represented a dose-response slope that was less than the other studied statins: atorvastatin, rosuvastatin, fluvastatin, pitavastatin and cerivastatin. From other systematic reviews we conducted on statins for its effect to reduce LDL cholesterol, pravastatin is similar to fluvastatin, but has a decreased effect compared to atorvastatin, rosuvastatin, pitavastatin and cerivastatin. The effect of pravastatin compared to placebo on WADES has a risk ratio (RR) of 0.81 (95% CI 0.63 to 1.03). The certainty of evidence was judged to be very low. AUTHORS' CONCLUSIONS: Pravastatin lowers blood total cholesterol, LDL cholesterol and triglyceride in a dose-dependent linear fashion. This review did not provide a good estimate of the incidence of harms associated with pravastatin because of the lack of reporting of adverse effects in 48.4% of the randomized placebo-controlled trials.

The impact of staging FDG-PET/CT on treatment for stage III NSCLC - an analysis of population-based data from Ontario, Canada.

Purpose: Fluoro-2-deoxyglucose positron-emission tomography (FDG-PET/CT) is now considered a standard investigation for the staging of new cases of stage III NSCLC. However, there is not published level 3 evidence demonstrating the impact of FDG-PET/CT on appropriate therapy in this setting. Using retrospective population-based data, we sought to examine the role and timing that FDG-PET/CT scans play in influencing treatment choice, as well as survival in patients diagnosed with stage III NSCLC. Materials and methods: A retrospective cohort of patients diagnosed with stage III NSCLC from 2009-2017 in Ontario were identified from the IC/ES (formerly Institute of Clinical Evaluative Sciences) database. FDG-PET/CT utilization over time, trends in mediastinal biopsy technique and usage, the impact of FDG-PET/CT on overall survival (OS), and its influence on use of concurrent chemoradiotherapy (CRT) were explored. The impact of timing of pre-treatment FDG-PET/CT on OS was also analyzed (≤28 days prior to treatment, 29-56 days prior, and >56 days prior). Results: Between 2007 and 2017, a total of 13 796 people were diagnosed with stage III NSCLC in Ontario. FDG-PET/CT utilization increased over time with 0% of cases in 2007 and 74% in 2017 with pre-treatment FDG-PET/CT scans. The number of patients who received a mediastinal biopsy similarly increased in this timeframe increasing from 41% to 53%. More patients with pre-treatment FDG-PET/CT scans received curative-intent therapy than those who did not: 23% vs 13% for CRT (p<0.001), and 23% vs 10% for surgery (p<0.001). Median OS was longer in those with FDG-PET/CT scans prior to treatment (17 vs 11 months), as was 5-year survival (22% vs 14%, p<0.001), and this held true on both univariate and multivariate analyses. Timing of FDG-PET/CT scan relative to treatment was not associated with differences in OS. Conclusion: Improvements in OS were seen in this cohort of stage III NSCLC patients who underwent a pre-treatment FDG-PET/CT scan. This can likely be attributed to stage-appropriate therapy due to more complete staging using FDG-PET/CT. This study stresses the importance of complete staging for suspected stage III NSCLC using FDG-PET/CT, and a need for continued advocacy for increased access to FDG-PET/CT scans.

Referring and Specialist Physician Gender and Specialist Billing.

Importance: While a gender pay gap in medicine has been well documented, relatively little research has addressed mechanisms that mediate gender differences in referral income for specialists. Objective: To examine gender-based disparities in medical and surgical specialist referrals in Ontario, Canada. Design, Setting, and Participants: This cross-sectional study included referrals for specialist care ascertained from Ontario Health Insurance Plan physician billings for fiscal year 2018 to 2019. Participants were specialist physicians who received new patient consultations from April 1, 2018, to March 31, 2019, and the associated referring physicians. Data were analyzed from April 2018 to March 2020, including a 12-month follow-up period. Exposures: Specialist and referring physician gender (female or male). Main Outcomes and Measures: Revenue per referral was defined based on an episode-of-care approach as total billings for a 12-month period from the initial consultation. Mean total billings for female and male specialists were compared and the differential divided into the portion owing to referral volume vs referral revenue. Difference-in-differences multivariable regression analysis was used to estimate gender-based differences in revenue per referral. For each referring physician, gender-based differences in referral patterns were examined using case-control analysis, in which specialists who received a referral were compared with matched control specialists who did not receive a referral. This analysis considered the gender of the specialist and concordance between the gender of the referring physician and specialist, among other characteristics. Results: Of 7 621 365 new referrals, 32 824 referring physicians, of whom 13 512 (41.2%) were female (mean [SD] age, 46.3 [11.6] years) and 19 312 (58.8%) were male (mean [SD] age, 52.9 [13.5] years), made referrals to 13 582 specialists, of whom 4890 (36.0%) were female (mean [SD] age, 45.6 [11.0] years) and 8692 (64.0%) were male (mean [SD] age, 51.8 [13.0] years). Male specialists received more mean (SD) referrals than did female specialists (633 [666] vs 433 [515]), and the mean (SD) revenue per referral was higher for males ($350 [$474]) compared with females ($316 [$393]). Adjusted analysis demonstrated a -4.7% (95% CI, -4.9% to -4.5%) difference in the revenue per referral between male and female specialists. Multivariable regression analysis found that physicians referred more often to specialists of the same gender (odds ratio, 1.04; 95% CI, 1.03-1.04) but had higher odds of referring to male specialists (odds ratio, 1.10; 95% CI, 1.09-1.11). Conclusions and Relevance: In this cross-sectional study of the gender pay gap in specialist referral income, the number and revenue from referrals received differed by gender, as did the odds of receiving a referral from a physician of the same gender. Future research should examine the effectiveness of different policies to address this gap, such as a centralized, gender-blinded referral system.

Predictors and disparities in neonatal and under 5 mortality in rural Pakistan: cross sectional analysis.

Background: Adopted in 2015, the sustainable development goals (SDGs) have set specific targets (SDG 3.2) for countries to reduce their neonatal mortality rate (NMR) to below 12 deaths per 1000 live births and under 5 mortality rate (U5MR) to below 25 deaths per 1000 live births by 2030. For Pakistan to achieve these targets, there is a need to measure these rates and understand the predictors of child mortality at sub-national level. Launched in 2016, the Umeed-e-Nau (UeN) or New Hope project is based on scaling up proven and effective Maternal and Newborn Child Health (MNCH) interventions in 8 of the highest burden districts of the country, using existing public sector platforms in Pakistan at both the community and facility level. The primary aim of the project is to reduce perinatal mortality in these districts by 20% from baseline. Methods: We report overall neonatal and post neonatal mortality rates for the two years preceding the UeN baseline household survey. Rates were calculated using the synthetic cohort probability method and predictors of neonatal and post neonatal mortality examined using Cox regression. To investigate spatial variations in the mortality rates, we calculated Moran's I at the district level using predicted probabilities of mortality. Finally, we create district level maps of predicted under 5 child mortality using a stochastic partial differentiation approach. Findings: A total of 26,258 children contributed to the analysis of mortality with 838 deaths in the neonatal period and 2236 under-5 deaths during the observation period from March 1, 2015 to March 17, 2017. Overall, we estimated the NMR to be 29.2 per 1000 live births (95% CI: 26.9-31.4) and the U5MR to be 86.1 per 1000 live births (95% CI: 85.5-86.8). We found evidence of within-district geospatial clustering of under 5 mortality (P < 0.0001) and that social factors (poverty, illiteracy, multiparity), poor coverage of community health workers and distance from health facilities were strongly associated with child mortality. Interpretation: Important factors associated with neonatal and post-neonatal mortality in our study population included maternal education, parity, household size and gender. Additionally, antenatal care coverage (at least 4 visits) was specifically associated with neonatal mortality only, whereas, LHW coverage and distance to health facility were strongly associated with post-neonatal mortality. These findings emphasise the need for comprehensive, multisectoral strategies to be implemented for future maternal and child health programs and outreach services in rural areas. Funding: The study was funded by an unrestricted grant from the Bill & Melinda Gates Foundation to the Aga Khan University (Grant OPP 1148892).