Insulin resistance is an underappreciated facet of type 1 diabetes that occurs with remarkable consistency and considerable magnitude. Although therapeutic innovations are continuing to normalize dysglycemia, a sizable body of data suggests a second metabolic abnormality—iatrogenic hyperinsulinemia—principally drives insulin resistance and its consequences in this population and has not been addressed. We review this evidence to show that injecting insulin into the peripheral circulation bypasses first-pass hepatic insulin clearance, which leads to the unintended metabolic consequence of whole-body insulin resistance. We propose restructuring insulin therapy to restore the physiological insulin balance between the hepatic portal and peripheral circulations and thereby avoid the complications of life-long insulin resistance. As technology rapidly advances and our ability to ensure euglycemia improves, iatrogenic insulin resistance will become the final barrier to overcome to restore normal physiology, health, and life in type 1 diabetes.

Impaired insulin secretion from the pancreatic β-cells is central in the pathogenesis of type 2 diabetes (T2D), and microRNAs (miRNAs) are fundamental regulatory factors in this process. Differential expression of miRNAs contributes to β-cell adaptation to compensate for increased insulin resistance, but deregulation of miRNA expression can also directly cause β-cell impairment during the development of T2D. miRNAs are small noncoding RNAs that posttranscriptionally reduce gene expression through translational inhibition or mRNA destabilization. The nature of miRNA targeting implies the presence of complex and large miRNA–mRNA regulatory networks in every cell, including the insulin-secreting β-cell. Here we exemplify one such network using our own data on differential miRNA expression in the islets of T2D Goto-Kakizaki rat model. Several biological processes are influenced by multiple miRNAs in the β-cell, but so far most studies have focused on dissecting the mechanism of action of individual miRNAs. In this Perspective we present key islet miRNA families involved in T2D pathogenesis including miR-200, miR-7, miR-184, miR-212/miR-132, and miR-130a/b/miR-152. Finally, we highlight four challenges and opportunities within islet miRNA research, ending with a discussion on how miRNAs can be utilized as therapeutic targets contributing to personalized T2D treatment strategies.

Yan Xing, Hongling Wei, Xiumei Xiao, Zekun Chen, Hui Liu, Xiaomei Tong, and Wei Zhou

Infants with intrauterine growth retardation (IUGR) have a high risk of developing bronchial asthma in childhood, but the underlying mechanisms remain unclear. This study aimed to disclose the role of vascular non-inflammatory molecule 1 (vannin-1, encoded by the Vnn1 gene) and its downstream signaling in IUGR asthmatic mice induced by ovalbumin. Significant histological alterations and an increase of vannin-1 expression were revealed in IUGR asthmatic mice, accompanied by elevated methylation of Vnn1 promoter regions. In IUGR asthmatic mice, we also found (i) a direct binding of HNF4α and PGC1α to Vnn1 promoter by ChIP assay; (ii) a direct interaction of HNF4α with PGC1α; (iii) upregulation of phospho-PI3K p85/p55 and phospho-Akt^Ser473 and downregulation of phospho-PTENT^yr366, and (iv) an increase in nuclear NFB p65 and a decrease in cytosolic IB-α. In primary cultured bronchial epithelial cells derived from the IUGR asthmatic mice, knockdown of Vnn1 prevented upregulation of phospho-Akt^Ser473 and an increase of reactive oxygen species (ROS) and TGF-β production. Taken together, we demonstrate that elevated vannin-1 activates the PI3K/Akt/NFB signaling pathway, leading to ROS and inflammation reactions responsible for asthma occurrence in IUGR individuals. We also disclose that interaction of PGC1α and HNF4α promotes methylation of Vnn1 promoter regions and then upregulates vannin-1 expression.

BackgroundPolycystic ovary syndrome (PCOS) is a common lifelong metabolic condition with serious associated comorbidities. Evidence points to a delay in diagnosis and inconsistency in the information provided to women with PCOS.AimTo capture women’s experiences of how PCOS is diagnosed and managed in UK general practice.Design and settingThis was a mixed-methods study with an online questionnaire survey and semi-structured telephone interviews with a subset of responders.MethodAn online survey to elicit women’s experiences of general practice PCOS care was promoted by charities and BBC Radio Leicester. The survey was accessible online between January 2018 and November 2018. A subset of responders undertook a semi-structured telephone interview to provide more in-depth data.ResultsA total of 323 women completed the survey (average age 35.4 years) and semi-structured interviews were conducted with 11 women. There were five key themes identified through the survey responses. Participants described a variable lag time from presentation to PCOS diagnosis, with a median of 6–12 months. Many had experienced mental health problems associated with their PCOS symptoms, but had not discussed these with the GP. Many were unable to recall any discussion about associated comorbidities with the GP. Some differences were identified between the experiences of women from white British backgrounds and those from other ethnic backgrounds.ConclusionFrom the experiences of the women in this study, it appears that PCOS in general practice is not viewed as a long-term condition with an increased risk of comorbidities including mental health problems. Further research should explore GPs’ awareness of comorbidities and the differences in PCOS care experienced by women from different ethnic backgrounds.

PURPOSE

We aimed to evaluate the efficacy and safety of use of the Fasting Algorithm for Singaporeans with Type 2 Diabetes (FAST) during Ramadan.

METHODS

We performed a prospective, multicenter, randomized controlled trial. The inclusion criteria were age ≥21 years, baseline glycated hemoglobin (HbA_1c) level ≤9.5%, and intention to fast for ≥10 days during Ramadan. Exclusion criteria included baseline estimated glomerular filtration rate <30 mL/min, diabetes-related hospitalization, and short-term corticosteroid therapy. Participants were randomized to intervention (use of FAST) or control (usual care without FAST) groups. Efficacy outcomes were HbA_1c level and fasting blood glucose and postprandial glucose changes, and the safety outcome was incidence of major or minor hypoglycemia during the Ramadan period. Glycemic variability and diabetes distress were also investigated. Linear mixed models were constructed to assess changes.

RESULTS

A total of 97 participants were randomized (intervention: n = 46, control: n = 51). The HbA_1c improvement during Ramadan was 4 times greater in the intervention group (–0.4%) than in the control group (–0.1%) (P = .049). The mean fasting blood glucose level decreased in the intervention group (–3.6 mg/dL) and increased in the control group (+20.9 mg/dL) (P = .034). The mean postprandial glucose level showed greater improvement in the intervention group (–16.4 mg/dL) compared to the control group (–2.3 mg/dL). There were more minor hypoglycemic events based on self-monitered blood glucose readings in the control group (intervention: 4, control: 6; P = .744). Glycemic variability was not significantly different between the 2 groups (P = .284). No between-group differences in diabetes distress were observed (P = .479).

CONCLUSIONS

Our findings emphasize the importance of efficacious, safe, and culturally tailored epistemic tools for diabetes management.

Background and objectives

Bioelectrical impedance analysis (BIA) devices can help assess volume overload in patients receiving maintenance peritoneal dialysis. However, the effects of BIA on the short-term hard end points of peritoneal dialysis lack consistency. This study aimed to test whether BIA-guided fluid management could improve short-term outcomes in patients on peritoneal dialysis.

Design, setting, participants, & measurements

A single-center, open-labeled, randomized, controlled trial was conducted. Patients on prevalent peritoneal dialysis with volume overload were recruited from July 1, 2013 to March 30, 2014 and followed for 1 year in the initial protocol. All participants with volume overload were 1:1 randomized to the BIA-guided arm (BIA and traditional clinical methods) and control arm (only traditional clinical methods). The primary end point was all-cause mortality and secondary end points were cardiovascular disease mortality and technique survival.

Results

A total of 240 patients (mean age, 49 years; men, 51%; diabetic, 21%, 120 per group) were enrolled. After 1-year follow-up, 11(5%) patients died (three in BIA versus eight in control) and 21 patients were permanently transferred to hemodialysis (eight in BIA versus 13 in control). The rate of extracellular water/total body water decline in the BIA group was significantly higher than that in the control group. The 1-year patient survival rates were 96% and 92% in BIA and control groups, respectively. No significant statistical differences were found between patients randomized to the BIA-guided or control arm in terms of patient survival, cardiovascular disease mortality, and technique survival (P>0.05).

Conclusions

Although BIA-guided fluid management improved the fluid overload status better than the traditional clinical method, no significant effect was found on 1-year patient survival and technique survival in patients on peritoneal dialysis.

Background and objectives

Large, randomized, controlled trials targeting higher hemoglobin level with erythropoiesis-stimulating agents for Western patients with CKD showed harm. However, the effect of anemia correction using erythropoiesis-stimulating agents may differ between CKD subpopulations. The Prevention of ESKD by Darbepoetin Alfa in CKD Patients with Non-diabetic Kidney Disease study, a multicenter, randomized, open-label, parallel-group study, aimed to examine the effect of targeting hemoglobin levels of 11–13 g/dl using darbepoetin alfa with reference to a low-hemoglobin target of 9–11 g/dl on kidney outcome in patients with advanced CKD without diabetes in Japan.

Design, setting, participants, & measurements

We enrolled 491 patients with CKD without diabetes, and an eGFR of 8–20 ml/min per 1.73 m². Of these 491 patients, 239 and 240 were ultimately assigned to the high- and low-hemoglobin groups, respectively (12 patients were excluded). The primary outcome was a kidney composite end point (starting maintenance dialysis, kidney transplantation, eGFR≤6 ml/min per 1.73 m², and 50% reduction in eGFR).

Results

Mean hemoglobin levels were 11.2±1.1 and 10.0±0.9 g/dl in the high- and low-hemoglobin groups, respectively, during the mean study period of 73.5±29.7 weeks. The kidney composite end point occurred in 105 (44%) and 116 (48%) patients in the high- and low-hemoglobin groups, respectively (log-rank test; P=0.32). The adjusted Cox proportional hazards model showed that the hazard ratio for the high- versus low-hemoglobin group was 0.78 (95% confidence interval, 0.60 to 1.03; P=0.08). Cardiovascular events occurred in 19 (8%) and 16 (7%) patients in each group, respectively, with no significant between-group difference (log-rank test; P=0.66).

Conclusions

Targeting a higher hemoglobin level (11–13 g/dl) with darbepoetin alfa did not improve kidney outcome compared with targeting a lower hemoglobin level (9–11 g/dl) in patients with advanced CKD without diabetes.

Clinical Trial registry name and registration number

Prevention of ESKD by Darbepoetin Alfa in CKD Patients with Non-diabetic Kidney Disease (PREDICT), NCT01581073.

Fnr is a transcriptional regulator that controls the expression of a variety of genes in response to oxygen limitation in bacteria. Genome sequencing revealed four genes (fnr1, fnr3, fnr5, and fnr7) coding for Fnr proteins in Paenibacillus polymyxa WLY78. Fnr1 and Fnr3 showed more similarity to each other than to Fnr5 and Fnr7. Also, Fnr1 and Fnr3 exhibited high similarity with Bacillus cereus Fnr and Bacillus subtilis Fnr in sequence and structures. Both the aerobically purified His-tagged Fnr1 and His-tagged Fnr3 in Escherichia coli could bind to the specific DNA promoter. Deletion analysis showed that the four fnr genes, especially fnr1 and fnr3, have significant impacts on growth and nitrogenase activity. Single deletion of fnr1 or fnr3 led to a 50% reduction in nitrogenase activity, and double deletion of fnr1 and fnr3 resulted to a 90% reduction in activity. Genome-wide transcription analysis showed that Fnr1 and Fnr3 indirectly activated expression of nif (nitrogen fixation) genes and Fe transport genes under anaerobic conditions. Fnr1 and Fnr3 inhibited expression of the genes involved in the aerobic respiratory chain and activated expression of genes responsible for anaerobic electron acceptor genes.

IMPORTANCE The members of the nitrogen-fixing Paenibacillus spp. have great potential to be used as a bacterial fertilizer in agriculture. However, the functions of the fnr gene(s) in nitrogen fixation and other metabolisms in Paenibacillus spp. are not known. Here, we found that in P. polymyxa WLY78, Fnr1 and Fnr3 were responsible for regulation of numerous genes in response to changes in oxygen levels, but Fnr5 and Fnr7 exhibited little effect. Fnr1 and Fnr3 indirectly or directly regulated many types of important metabolism, such as nitrogen fixation, Fe uptake, respiration, and electron transport. This study not only reveals the function of the fnr genes of P. polymyxa WLY78 in nitrogen fixation and other metabolisms but also will provide insight into the evolution and regulatory mechanisms of fnr in Paenibacillus.

Biological nitrogen fixation can be an important source of nitrogen in tropical forests that serve as a major CO₂ sink. Extensive deforestation of the Amazon is known to influence microbial communities and the biogeochemical cycles they mediate. However, it is unknown how diazotrophs (nitrogen-fixing microorganisms) respond to deforestation and subsequent ecosystem conversion to agriculture, as well as whether they can recover in secondary forests that are established after agriculture is abandoned. To address these knowledge gaps, we combined a spatially explicit sampling approach with high-throughput sequencing of nifH genes. The main objectives were to assess the functional distance decay relationship of the diazotrophic bacterial community in a tropical forest ecosystem and to quantify the roles of various factors that drive the observed changes in the diazotrophic community structure. We observed an increase in local diazotrophic diversity (α-diversity) with a decrease in community turnover (β-diversity), associated with a shift in diazotrophic community structure as a result of the forest-to-pasture conversion. Both diazotrophic community turnover and structure showed signs of recovery in secondary forests. Changes in the diazotrophic community were primarily driven by the change in land use rather than differences in geochemical characteristics or geographic distances. The diazotroph communities in secondary forests resembled those in primary forests, suggesting that at least partial recovery of diazotrophs is possible following agricultural abandonment.

IMPORTANCE The Amazon region is a major tropical forest region that is being deforested at an alarming rate to create space for cattle ranching and agriculture. Diazotrophs (nitrogen-fixing microorganisms) play an important role in supplying soil N for plant growth in tropical forests. It is unknown how diazotrophs respond to deforestation and whether they can recover in secondary forests that establish after agriculture is abandoned. Using high-throughput sequencing of nifH genes, we characterized the response of diazotrophs’ β-diversity and identified major drivers of changes in diazotrophs from forest-to-pasture and pasture-to-secondary-forest conversions. Studying the impact of land use change on diazotrophs is important for a better understanding of the impact of deforestation on tropical forest ecosystem functioning, and our results on the potential recovery of diazotrophs in secondary forests imply the possible restoration of ecosystem functions in secondary forests.

Background:

Unnecessary antibiotic use in the community in Canada is not well defined. Our objective was to quantify unnecessary antibiotic prescribing in a Canadian primary care setting.

Methods:

We performed a descriptive analysis in Ontario from April 2011 to March 2016 using the Electronic Medical Records Primary Care database linked to other health administrative data sets at ICES. We determined antibiotic prescribing rates (per 100 patient–physician encounters) for 23 common conditions and estimated rates of unnecessary prescribing using predefined expected prescribing rates, both stratified by condition and patient age group.

Results:

The study included 341 physicians, 204 313 patients and 499 570 encounters. The rate of unnecessary antibiotic prescribing for included conditions was 15.4% overall and was 17.6% for those less than 2 years of age, 18.6% for those aged 2–18, 14.5% for those aged 19–64 and 13.0% for those aged 65 or more. The highest unnecessary prescribing rates were observed for acute bronchitis (52.6%), acute sinusitis (48.4%) and acute otitis media (39.3%). The common cold, acute bronchitis, acute sinusitis and miscellaneous nonbacterial infections were responsible for 80% of the unnecessary antibiotic prescriptions. Of all antibiotics prescribed, 12.0% were for conditions for which they are never indicated, and 12.3% for conditions for which they are rarely indicated. In children, 25% of antibiotics were for conditions for which they are never indicated (e.g., common cold).

Interpretation:

Antibiotics were prescribed unnecessarily for 15.4% of included encounters in a Canadian primary care setting. Almost one-quarter of antibiotics were prescribed for conditions for which they are rarely or never indicated. These findings should guide safe reductions in the use of antibiotics for the common cold, bronchitis and sinusitis.

Background:

Previous studies examining potential sex and gender bias in the Canadian Resident Matching Service (CaRMS) match have had conflicting results. We examined the results of the CaRMS match over the period 2013–2019 to determine the potential association between applicants’ gender and the outcome of matching to their first-choice discipline.

Methods:

In this cross-sectional analysis, we determined the risk of matching to one’s first-choice discipline in CaRMS by applicant gender and year, for all Canadian medical students who participated in the first iteration of the R-1 match for the years 2013 to 2019. We analyzed data in 3 categories of disciplines according to CaRMS classifications: family medicine, nonsurgical disciplines and surgical disciplines. We excluded disciplines with fewer than 10 applicants.

Results:

Match results were available for 20 033 participants, of whom 11 078 (55.3%) were female. Overall, female applicants were significantly more likely to match to their first-choice discipline (relative risk [RR] 1.03, 95% confidence interval [CI] 1.02–1.04). After adjustment for match year and stratification by discipline categories, we found that female applicants were more likely to match to family medicine as their first choice (RR 1.04, 95% CI 1.03–1.05) and less likely to match to a first-choice surgical discipline (RR 0.95, 95% CI 0.91–1.00) than their male peers. There was no significant difference between the genders in matching to one’s first-choice nonsurgical discipline (RR 1.01, 95% CI 0.99–1.03).

Interpretation:

These results suggest an association between an applicant’s gender and the probability of matching to one’s first-choice discipline. The possibility of gender bias in the application process for residency programs should be further evaluated and monitored.

Background:

Historically, some chiropractors have been critical of vaccination, and this has been the subject of recent media attention in Canada. We explored the association between media attention and public dissemination of vaccination information on Canadian chiropractors’ websites.

Methods:

In 2016, we identified all Canadian chiropractors’ websites that provided information on vaccination by extracting details from the regulatory college website for each province using the search engine on their "find a chiropractor" page. We assessed the quality of information using the Web Resource Rating Tool (scores range from 0% [worst] to 100% [best]), determined whether vaccination was portrayed in a positive, neutral or negative manner, and conducted thematic analysis of vaccination content. We revisited all identified websites in 2019 to explore for changes to posted vaccination material.

Results:

In July 2016, of 3733 chiropractic websites identified, 94 unique websites provided information on vaccination: 59 (63%) gave negative messaging, 19 (20%) were neutral and 16 (17%) were positive. The quality of vaccination content on the websites was generally poor, with a median Web Resource Rating Tool score of 19%. We identified 4 main themes: there are alternatives to vaccination, vaccines are harmful, evidence regarding vaccination and health policy regarding vaccination. From 2012 to 2016, there was 1 Canadian newspaper story concerning antivaccination statements by chiropractors, whereas 51 news articles were published on this topic between 2017 and 2019. In April 2019, 45 (48%) of the 94 websites we had identified in 2016 had removed all vaccination content or had been discontinued.

Interpretation:

In 2016, a minority of Canadian chiropractors provided vaccination information on their websites, the majority of which portrayed vaccination negatively. After substantial national media attention, about half of all vaccination material on chiropractors’ websites was removed within several years.

Background:

First Nations people in Ontario have an increased prevalence of diabetes compared to other people in the province. This study examined use of health care services by First Nations people with diabetes and other people with diabetes in Ontario.

Methods:

Using linked health administrative databases, we identified all people in Ontario with diabetes as of Apr. 1, 2014. We identified First Nations people using the Indian Register. We looked at outcomes from Apr. 1, 2014, to Mar. 31, 2015. We determined the proportion of people with a regular family physician and their continuity of care with that physician. We also examined visits with specialists for diabetes care, hospital admissions for ambulatory-care–sensitive conditions, and emergency department visits for hypo- or hyperglycemia.

Results:

There were 1 380 529 people diagnosed with diabetes in Ontario as of Apr. 1, 2014, of whom 22 952 (1.7%) were First Nations people. First Nations people were less likely to have a regular family physician (85.3% v. 97.7%) and had lower continuity of care with that physician (mean score for continuity of care 74.6 v. 77.7) than other people in Ontario. They were also less likely to see specialists. First Nations people were more likely to be admitted to hospital for ambulatory-care–sensitive conditions (2.4% v. 1.2%) and to have an emergency department visit for hypo- or hyperglycemia (1.5% v. 0.8%). Disparities were particularly marked for those living in First Nations communities.

Interpretation:

First Nations people with diabetes in Ontario had poorer access to and use of primary care than other people with diabetes in the province. These findings may help explain continued disparities in the rates of complications related to diabetes.

Background:

Drugs are the fastest growing cost in the Canadian health care system, owing to the increasing number of high-cost drugs. The objective of this study was to examine the characteristics of high–drug-cost beneficiaries of public drug plans across Canada relative to other beneficiaries.

Methods:

We conducted a cross-sectional study among public drug plan beneficiaries residing in all provinces except Quebec. We used the Canadian Institute for Health Information’s National Prescription Drug Utilization Information System to identify all drugs dispensed to beneficiaries of public drug programs in 2016/17. We stratified the cohort into 2 groups: high–drug-cost beneficiaries (top 5% of beneficiaries based on annual costs) and other beneficiaries (remaining 95%). For each group, we reported total drug costs, prevalence of high-cost claims (> $1000), median number of drugs, proportion of beneficiaries aged 65 or more, the 10 most costly reimbursed medications and the 10 medications most commonly reimbursed. We reported estimates overall and by province.

Results:

High–drug-cost beneficiaries accounted for nearly half (46.5%) of annual spending, with an average annual spend of $14 610 per beneficiary, compared to $1570 among other beneficiaries. The median number of drugs dispensed was higher among high–drug-cost beneficiaries than among other beneficiaries (13 [interquartile range (IQR) 7–19] v. 8 [IQR 4–13]), and a much larger proportion of high–drug-cost beneficiaries than other beneficiaries received at least 1 high-cost claim (40.9% v. 0.6%). Long-term medications were the most commonly used medications for both groups, whereas biologics and antivirals were the most costly medications for high–drug-cost beneficiaries.

Interpretation:

High–drug-cost beneficiaries were characterized by the use of expensive medications and polypharmacy relative to other beneficiaries. Interventions and policies to help reduce spending need to consider both of these factors.

Background:

In Canada, First Nations populations experience a higher incidence of diabetes and diabetes-related complications than other people. Given the paucity of information on use of preventive eye examinations and the need for interventional care for severe retinopathy among First Nations people, we carried out a population-based study to compare rates of eye examinations and interventional therapies to treat vision-threatening stages of diabetic retinopathy among First Nations people and other people with diabetes in Ontario.

Methods:

In collaboration with the Chiefs of Ontario, we carried out a population-based study to identify cohorts of First Nations people and other people with diabetes in Ontario from 1995/96 to 2014/15. We used linked health administrative databases to evaluate rates of eye examination (2005/06–2014/15) and severe diabetic retinopathy treatment and compared them between the 2 populations, and between First Nations people living in and outside of First Nations communities.

Results:

We identified 23 013 First Nations people and 1 364 222 other people diagnosed with diabetes from 1995/96 to 2014/15, of whom 49.8% (95% confidence interval [CI] 48.9%–50.7%) and 53.8% (95% CI 53.7%–54.0%), respectively, received an eye examination in 2014/15. Eye examination rates were similar for First Nations people regardless of whether they lived in or outside a First Nations community. First Nations people developed severe diabetic retinopathy at a faster rate than other people (hazard ratio 1.19, 95% CI 1.02–1.38). The gap between First Nations people and other people in the proportion requiring therapy for severe diabetic retinopathy was especially prominent among younger people. There were no significant differences in rates of diabetic retinopathy treatment in First Nations people stratified by place of residence.

Interpretation:

Eye examination rates remain suboptimal among people with diabetes in Ontario and were lower among First Nations people. This is particularly concerning in light of our other findings showing an increased risk of requiring treatment for advanced diabetic retinopathy and the accelerated rate of diabetic retinopathy progression among First Nations people with diabetes.

Background:

Deaths from respiratory tract infections (RTIs) in children are preventable through timely access to public health and medical interventions. We aimed to assess whether socioeconomic disparities in mortality related to pediatric RTI persisted after accounting for health status at birth.

Methods:

We compared the prevalence of and risk factors for RTI-related death in singletons aged 28 days to 4 years across Ontario (Canada), Scotland and England (jurisdictions with universal health care) using linked administrative data for 2003–2013. We estimated rates of RTI-related mortality for children living in deprived areas and those born to teenage girls; we estimated both crude rates and those adjusted for health status at birth.

Results:

A total of 1 299 240 (Ontario), 547 556 (Scotland) and 3 910 401 (England) children were included in the study. Across all jurisdictions, children born in the most deprived areas experienced the highest rates of RTI-related mortality. After adjustment for high-risk chronic conditions and prematurity, we observed differences in mortality according to area-level deprivation in Ontario and England but not in Scotland. In Ontario, teenage motherhood was also an independent risk factor for RTI-related mortality.

Interpretation:

Socioeconomic disparities played a substantial role in child mortality related to RTI in all 3 jurisdictions. Context-specific investigations around the mechanisms of this increased risk and development of programs to address socioeconomic disparities are needed.

Background:

Care services have not been sufficiently adapted to meet the comprehensive care needs of women living with HIV. Our study objective was to engage patients and providers in codesigning care recommendations to improve care for this population in the province of Quebec.

Methods:

We conducted a 5-hour deliberative dialogue workshop in April 2019 in Montréal as the final phase of a mixed-methods study investigating comprehensive care for women living with HIV. The study drew on data from the Canadian HIV Women’s Sexual and Reproductive Health Cohort Study (CHIWOS). Recruitment was guided by a purposive maximum-variation sampling strategy to ensure an appropriate mix of participants and was facilitated by our existing CHIWOS networks. Participants included patients (women living with HIV) and HIV care providers (doctors, nurses, pharmacists). The workshop was facilitated professionally and included a synthesis of the evidence, small- and large-group deliberations, and voting on care improvements.

Results:

Eight patients and 8 HIV care providers participated. Drawing on identified care priorities, the participants identified 4 relatively rapid care improvements and 3 longer-term improvements. The rapid care improvements included delegating medical acts to members of multidisciplinary care teams; greater involvement of HIV community members within care settings and health care decision-making; creating a women’s health information booklet; and increasing HIV education among all health care providers and raising awareness of women’s care needs beyond HIV-specific care among HIV care providers. The longer-term care improvements included advocating for complete financial coverage of antiretroviral therapy within the government-sponsored Medicare program, facilitating access to allied care providers (e.g., physiotherapists and psychologists) and launching a population-wide campaign to increase awareness about the Undetectable = Untransmittable (U=U) initiative and other HIV advances.

Interpretation:

The deliberative dialogue workshop yielded evidence-based, stakeholder-driven recommendations to improve the comprehensive care of women living with HIV in Quebec.

Clostridioides difficileDiagnosticsMetabolomicsMicrobiome

At the end of 2019 and early 2020, an outbreak of pneumonia of unknown etiology emerged in the city of Wuhan in China. The cases were found to be caused by a novel beta coronavirus, which was subsequently named SARS-CoV-2 by the World Health Organization (WHO). The virus has since spread further in China and to other regions of the world, having infected more than 88 K people, and causing close to 3000 deaths as of March 1, 2020. More than 50 million people remain in quarantine at this time. Scientists and clinicians globally are working swiftly to combat COVID-19, the respiratory disease caused by the virus. Notably, diagnostic assays have been developed rapidly in many countries, and have played significant roles in diagnosis, monitoring, surveillance, and infection control. Starting February 29, 2020, the development and performance of molecular testing for SARS-CoV-2 in high complexity Clinical Laboratory Improvement Amendments (CLIA) laboratories prior to emergency use authorization was allowed by the US FDA. Although the epidemic is evolving rapidly, many valuable lessons have been learned and many questions remain to be answered. Here we invited multiple experts across the globe from clinical laboratories, public health laboratories, infection control, and diagnostic industry to share their views on the diagnosis, infection control, and public perception of SARS-CoV-2.

The aim of this study was to assess the association of high-sensitivity cardiac troponin (hs-cTnT) and other cardiac, kidney, hyperglycemia, and inflammatory biomarkers with peripheral neuropathy (PN) in a community-based population.We conducted a cross-sectional analysis of 3056 black and white participants in the Atherosclerosis Risk in Communities (ARIC) study who underwent standardized monofilament PN testing and had measures of cardiac function (hs-cTnT, N-terminal pro–B-type natriuretic peptide [NT-proBNP], and growth differentiation factor 15 [GDF15]), kidney function (serum creatinine, cystatin C, β-2 microglobulin, urine albumin-to-creatinine ratio), hyperglycemia (fasting glucose, hemoglobin A_1c [Hb A_1c], fructosamine, glycated albumin, 1,5-anhydroglucitol), and inflammation (C-reactive protein) assessed at visit 6 (2016–2017; age 71–94 years). We used logistic regression to assess the associations of these biomarkers (modeled in diabetes-specific tertiles) with PN in older adults with and without diabetes after adjusting for traditional risk factors.In total, 33.5% of participants had PN (37.3% with diabetes and 31.9% without diabetes). There was an independent association of hs-cTnT with PN regardless of diabetes status (diabetes T3 vs. T1: odds ratio [OR], 2.15 [95% CI, 1.44–3.22]; no diabetes: OR, 2.31 [95%CI, 1.76–3.03]; P = 0.72 for interaction). Among participants without diabetes, there were also significant associations of NT-proBNP (OR, 1.40 [95% CI, 1.08–1.81]) and urine albumin-to-creatinine ratio (OR, 1.55 [95% CI, 1.22–1.97]) with PN. Associations of hyperglycemia biomarkers including Hb A_1c (OR, 1.76 [95% CI, 1.22–2.54]), fructosamine (OR, 1.71 [95% CI, 1.19–2.46]), and glycated albumin (OR, 1.45 [95% CI, 1.03–2.03]) with PN were significant only among participants with diabetes.Overall, hs-cTnT appears to be a global marker of end organ damage, including PN. Laboratory biomarkers may be able to help us identify those individuals with PN.

Copy number variation (CNV) in the salivary amylase gene (AMY1) modulates salivary α-amylase levels and is associated with postprandial glycemic traits. Whether AMY1-CNV plays a role in age-mediated change in insulin resistance (IR) is uncertain.We measured AMY1-CNV using duplex quantitative real-time polymerase chain reaction in two studies, the Boston Puerto Rican Health Study (BPRHS, n = 749) and the Genetics of Lipid-Lowering Drug and Diet Network study (GOLDN, n = 980), and plasma metabolomic profiles in the BPRHS. We examined the interaction between AMY1-CNV and age by assessing the relationship between age with glycemic traits and type 2 diabetes (T2D) according to high or low copy numbers of the AMY1 gene. Furthermore, we investigated associations between metabolites and interacting effects of AMY1-CNV and age on T2D risk.We found positive associations of IR with age among subjects with low AMY1-copy-numbers in both studies. T2D was marginally correlated with age in participants with low AMY1-copy-numbers but not with high AMY1-copy-numbers in the BPRHS. Metabolic pathway enrichment analysis identified the pentose metabolic pathway based on metabolites that were associated with both IR and the interactions between AMY1-CNV and age. Moreover, in older participants, high AMY1-copy-numbers tended to be associated with lower levels of ribonic acid, erythronic acid, and arabinonic acid, all of which were positively associated with IR.We found evidence supporting a role of AMY1-CNV in modifying the relationship between age and IR. Individuals with low AMY1-copy-numbers tend to have increased IR with advancing age.

Recognizing that guideline-directed histologic grading of endomyocardial biopsy tissue samples for rejection surveillance has limited diagnostic accuracy, quantitative, in situ characterization was performed of several important immune cell types in a retrospective cohort of clinical endomyocardial tissue samples. Differences between cases were identified and were grouped by histologic grade versus clinical rejection trajectory, with significantly increased programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cells suppressed in clinically evident rejections, especially cases with marked clinical-histologic discordance. Programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cell proportions are also significantly higher in "never-rejection" when compared with "future-rejection." These findings suggest that in situ immune modulators regulate the severity of cardiac allograft rejection.

In low-dose computed tomography (LDCT) screening for lung cancer, all three main conditions for overdiagnosis in cancer screening are present: 1) a reservoir of slowly or nongrowing lung cancer exists; 2) LDCT is a high-resolution imaging technology with the potential to identify this reservoir; and 3) eligible screening participants have a high risk of dying from causes other than lung cancer. The degree of overdiagnosis in cancer screening is most validly estimated in high-quality randomised controlled trials (RCTs), with enough follow-up time after the end of screening to avoid lead-time bias and without contamination of the control group.

Nine RCTs investigating LDCT screening were identified. Two RCTs were excluded because lung cancer incidence after the end of screening was not published. Two other RCTs using active comparators were also excluded. Therefore, five RCTs were included: two trials were at low risk of bias, two of some concern and one at high risk of bias. In a meta-analysis of the two low risk of bias RCTs including 8156 healthy current or former smokers, 49% of the screen-detected cancers were overdiagnosed. There is uncertainty about this substantial degree of overdiagnosis due to unexplained heterogeneity and low precision of the summed estimate across the two trials.

Key points

Nine randomised controlled trials (RCTs) on low-dose computed tomography screening were identified; five were included for meta-analysis but only two of those were at low risk of bias.

In a meta-analysis of recent low risk of bias RCTs including 8156 healthy current or former smokers from developed countries, we found that 49% of the screen-detected cancers may be overdiagnosed.

There is uncertainty about the degree of overdiagnosis in lung cancer screening due to unexplained heterogeneity and low precision of the point estimate.

If only high-quality RCTs are included in the meta-analysis, the degree of overdiagnosis is substantial.

Educational aims

To appreciate that low-dose computed tomography screening for lung cancer meets all three main conditions for overdiagnosis in cancer screening: a reservoir of indolent cancers exists in the population; the screening test is able to "tap" this reservoir by detecting biologically indolent cancers as well as biologically important cancers; and the population being screened is characterised by a relatively high competing risk of death from other causes

To learn about biases that might affect the estimates of overdiagnosis in randomised controlled trials in cancer screening

Tigecycline serves as one of the antibiotics of last resort to treat multidrug-resistant (including carbapenem-resistant) pathogens. However, the recently emerged plasmid-mediated tigecycline resistance mechanism, Tet(X), challenges the clinical efficacy of this class of antibiotics. In this study, we detected 180 tet(X)-harboring Acinetobacter isolates (8.9%, n = 180) from 2,018 samples collected from avian farms and adjacent environments in China. Eighteen tet(X)-harboring isolates (10.0%) were found to cocarry the carbapenemase gene bla_NDM-1, mostly from waterfowl samples (94.4%, 17/18). Interestingly, among six Acinetobacter strains, tet(X) and bla_NDM-1 were found to colocalize on the same plasmids. Moreover, whole-genome sequencing (WGS) revealed a novel orthologue of tet(X) in the six isolates coharboring tet(X) and bla_NDM-1. Inverse PCR suggested that the two tet(X) genes form a single transposable unit and may be cotransferred. Sequence comparison between six tet(X)- and bla_NDM-1-coharboring plasmids showed that they shared a highly homologous plasmid backbone even though they were isolated from different Acinetobacter species (three from Acinetobacter indicus, two from Acinetobacter schindleri, and one from Acinetobacter lwoffii) from various sources and from different geological regions, suggesting the horizontal genetic transfer of a common tet(X)- and bla_NDM-1-coharboring plasmid among Acinetobacter species in China. Emergence and spread of such plasmids and strains are of great clinical concern, and measures must be implemented to avoid their dissemination.

Antiretroviral therapy (ART) suppresses HIV-1 replication but fails to cure the infection. The presence of an extremely stable viral latent reservoir, primarily in resting memory CD4⁺ T cells, remains a major obstacle to viral eradication. The "shock and kill" strategy targets these latently infected cells and boosts immune recognition and clearance, and thus, it is a promising approach for an HIV-1 functional cure. Although some latency-reversing agents (LRAs) have been reported, no apparent clinical progress has been made, so it is still vital to seek novel and effective LRAs. Here, we report that thiostrepton (TSR), a proteasome inhibitor, reactivates latent HIV-1 effectively in cellular models and in primary CD4⁺ T cells from ART-suppressed individuals ex vivo. TSR does not induce global T cell activation, severe cytotoxicity, or CD8⁺ T cell dysfunction, making it a prospective LRA candidate. We also observed a significant synergistic effect of reactivation when TSR was combined with JQ1, prostratin, or bryostatin-1. Interestingly, six TSR analogues also show reactivation abilities that are similar to or more effective than that of TSR. We further verified that TSR upregulated expression of heat shock proteins (HSPs) in CD4⁺ T cells, which subsequently activated positive transcriptional elongation factor b (p-TEFb) and NF-B signals, leading to viral reactivation. In summary, we identify TSR as a novel LRA which could have important significance for applications to an HIV-1 functional cure in the future.

Helicobacter pylori is an important risk factor for gastric ulcers. However, antibacterial therapies increase the resistance rate and decrease the eradication rate of H. pylori. Inspired by the microaerophilic characteristics of H. pylori, we aimed at effectively establishing an oxygen-enriched environment to eradicate and prevent the recurrence of H. pylori. The effect and the mechanism of an oxygen-enriched environment in eradicating H. pylori and preventing the recurrence were explored in vitro and in vivo. During oral administration and after drug withdrawal, H. pylori counts were evaluated by Giemsa staining in animal cohorts. An oxygen-enriched environment in which H. pylori could not survive was successfully established by adding hydrogen peroxide into several solutions and rabbit gastric juice. Hydrogen peroxide effectively killed H. pylori in Columbia blood agar and special peptone broth. Minimum inhibition concentrations and minimum bactericidal concentrations of hydrogen peroxide were both relatively stable after promotion of resistance for 30 generations, indicating that hydrogen peroxide did not easily promote resistance in H. pylori. In models of Mongolian gerbils and Kunming mice, hydrogen peroxide has been shown to significantly eradicate and effectively prevent the recurrence of H. pylori without toxicity and damage to the gastric mucosa. The mechanism of hydrogen peroxide causing H. pylori death was related to the disruption of bacterial cell membranes. The oxygen-enriched environment achieved by hydrogen peroxide eradicates and prevents the recurrence of H. pylori by damaging bacterial cell membranes. Hydrogen peroxide thus provides an attractive candidate for anti-H. pylori treatment.

Dalbavancin offers a possible treatment option for infectious peritonitis associated with peritoneal dialysis (PD) due to its coverage of Gram-positive bacteria and pharmacokinetic properties. We aimed to evaluate the clinical pharmacokinetics (PK) and pharmacodynamics of dalbavancin in a prospective, randomized, open-label, crossover PK study of adult patients with end-stage renal disease ESRD who were receiving PD. Sampling occurred prior to a single 30-min infusion of dalbavancin at 1,500 mg and at 1, 2, 3, 4, and 6 h and 7 and 14 days postadministration. Concentration-time data were analyzed via noncompartmental analysis. Pharmacodynamic parameters against common infectious peritonitis-causing pathogens were evaluated. Ten patients were enrolled. Patients were a median of 55 years old and had a median weight of 78.2 kg, 50% were female, and 70% were Caucasian. The terminal plasma half-life of dalbavancin was 181.4 ± 35.5 h. The day 0 to day 14 dalbavancin mean area under the curve (AUC) was 40,573.2 ± 9,800.3 mg·h/liter. The terminal-phase half-life of dalbavancin within the peritoneal fluid was 4.309 x 10⁸ ± 1.140 x 10⁹ h. The day 0 to day 14 dalbavancin mean peritoneal fluid AUC was 2,125.0 ± 1,794.3 mg·h/liter. The target plasma AUC/MIC was attained with the intravenous dose in all 10 patients for all Staphylococcus and Streptococcus species at the recommended MIC breakpoints. The intraperitoneal arm of the study was stopped early, because the first 3 patients experienced moderate to severe pain and bloating within 1 h following the administration of dalbavancin. Dalbavancin at 1,500 mg administered intravenously can be utilized without dose adjustment in peritoneal dialysis patients and will likely achieve the necessary peritoneal fluid concentrations to treat peritonitis caused by typical Gram-positive pathogens.

A fosfomycin-resistant and carbapenemase (OXA-48)-producing Klebsiella pneumoniae isolate was recovered, and whole-genome sequencing revealed ISEcp1-bla_CTX-M-14b tandemly inserted upstream of the chromosomally encoded lysR-fosA locus. Quantitative evaluation of the expression of lysR and fosA genes showed that this insertion brought a strong hybrid promoter leading to overexpression of the fosA gene, resulting in fosfomycin resistance. This work showed the concomitant acquisition of resistance to broad-spectrum cephalosporins and fosfomycin due to a single genetic event.

Amplification of and oncogenic mutations in ERBB2, the gene encoding the HER2 receptor tyrosine kinase, promote receptor hyperactivation and tumor growth. Here we demonstrate that HER2 ubiquitination and internalization, rather than its overexpression, are key mechanisms underlying endocytosis and consequent efficacy of the anti-HER2 antibody–drug conjugates (ADC) ado-trastuzumab emtansine (T-DM1) and trastuzumab deruxtecan (T-DXd) in lung cancer cell lines and patient-derived xenograft models. These data translated into a 51% response rate in a clinical trial of T-DM1 in 49 patients with ERBB2-amplified or -mutant lung cancers. We show that cotreatment with irreversible pan-HER inhibitors enhances receptor ubiquitination and consequent ADC internalization and efficacy. We also demonstrate that ADC switching to T-DXd, which harbors a different cytotoxic payload, achieves durable responses in a patient with lung cancer and corresponding xenograft model developing resistance to T-DM1. Our findings may help guide future clinical trials and expand the field of ADC as cancer therapy.

Significance:

T-DM1 is clinically effective in lung cancers with amplification of or mutations in ERBB2. This activity is enhanced by cotreatment with irreversible pan-HER inhibitors, or ADC switching to T-DXd. These results may help address unmet needs of patients with HER2-activated tumors and no approved targeted therapy.

See related commentary by Rolfo and Russo, p. 643.

This article is highlighted in the In This Issue feature, p. 627

Tumor-derived retinoic acid promotes monocyte differentiation into immunosuppressive macrophages.

Gastric cancer (GC) is the fifth-ranked cancer type by associated mortality. The proportion of early diagnosis is low, and most patients are diagnosed at the advanced stages. First-line therapy standardly includes fluoropyrimidines and platinum compounds with trastuzumab for HER2-positive cases. For recurrent disease, there are several alternative options including ramucirumab, a monoclonal therapeutic antibody that inhibits VEGF-mediated tumor angiogenesis by binding with VEGFR2, alone or in combination with other cancer drugs. However, overall response rate following ramucirumab or its combinations is 30%–80% of the patients, suggesting that personalization of drug prescription is needed to increase efficacy of treatment. We report here original tumor RNA sequencing profiles for 15 advanced GC patients linked with data on clinical response to ramucirumab or its combinations. Three genes showed differential expression in the tumors for responders versus nonresponders: CHRM3, LRFN1, and TEX15. Of them, CHRM3 was up-regulated in the responders. Using the bioinformatic platform Oncobox we simulated ramucirumab efficiency and compared output model results with actual tumor response data. An agreement was observed between predicted and real clinical outcomes (AUC ≥ 0.7). These results suggest that RNA sequencing may be used to personalize the prescription of ramucirumab for GC and indicate potential molecular mechanisms underlying ramucirumab resistance. The RNA sequencing profiles obtained here are fully compatible with the previously published Oncobox Atlas of Normal Tissue Expression (ANTE) data.

We report the diagnostic challenges and the clinical course of a patient with an extraordinary presentation of B-lymphoblastic leukemia (B-ALL) with eosinophilia. We identified a novel ZBTB20-JAK2 gene fusion as a chimeric RNA transcript using the Archer platform. This gene fusion from the same patient was recently identified by Peterson et al. (2019) at the genomic level using a different sequencing technology platform. The configuration of this gene fusion predicts the production of a kinase-activating JAK2 fusion protein, which would normally lead to a diagnosis of Philadelphia chromosome–like B-ALL (Ph-like B-ALL). However, the unusual presentation of eosinophilia led us to demonstrate the presence of this gene fusion in nonlymphoid hematopoietic cells by fluorescence in situ hybridization (FISH) studies with morphologic correlation. Therefore, we believe this disease, in fact, represents blast crisis arising from an underlying myeloid neoplasm with JAK2 rearrangements. This case illustrates the difficulty in differentiating Ph-like B-ALL and myeloid/lymphoid neoplasm with eosinophilia and gene rearrangements (MLN-EGR) in blast crisis. As currently defined, the diagnosis of MLN-EGR relies on the hematologic presentations and the identification of marker gene fusions (including PCM1-JAK2, ETV6-JAK2, and BCR-JAK2). However, these same gene fusions, when limited to B-lymphoblasts, also define Ph-like B-ALL. Yet, our case does not conform to either condition. Therefore, the assessment for lineage restriction of gene rearrangements to reflect the pathophysiologic difference between B-ALL and MLN-EGR in blast crisis is likely a more robust diagnostic approach and allows the inclusion of MLN-EGR with novel gene fusions.

Wilms tumor (WT) is the most common renal malignancy of childhood and accounts for 6% of all childhood malignancies. With current therapies, the 5-yr overall survival (OS) for children with unilateral favorable histology WT is greater than 85%. The prognosis is worse, however, for the roughly 15% of patients who relapse, with only 50%–80% OS reported in those with recurrence. Herein, we describe the extended and detailed clinical course of a rare case of a child with recurrent, pulmonary metastatic, favorable histology WT harboring a BRAF V600E mutation. The BRAF V600E mutation, commonly found in melanoma and other cancers, and previously undescribed in WT, has recently been reported by our group in a subset of epithelial-predominant WT. This patient, who was included in that series, presented with unilateral, stage 1, favorable histology WT and was treated with standard chemotherapy. Following the completion of therapy, the patient relapsed with pulmonary metastatic disease, that then again recurred despite an initial response to salvage chemotherapy and radiation. Next-generation sequencing (NGS) on the metastatic pulmonary nodule revealed a BRAF V600E mutation. After weighing the therapeutic options, a novel approach with dual BRAF/MEK inhibitor combination therapy was initiated. Complete radiographic response was observed following 4 months of therapy with dabrafenib and trametinib. At 12 months following the start of BRAF/MEK combination treatment, the patient continues with a complete response and has experienced minimal treatment-related side effects. This represents the first case, to our knowledge, of effective treatment with BRAF/MEK molecularly targeted therapy in a pediatric Wilms tumor patient.

Understanding how coronary blood vessels form and regenerate during development and progression of cardiac diseases will shed light on the development of new treatment options targeting coronary artery diseases. Recent studies with the state-of-the-art technologies have identified novel origins of, as well as new, cellular and molecular mechanisms underlying the formation of coronary vessels in the postnatal heart, including collateral artery formation, endocardial-to-endothelial differentiation and mesenchymal-to-endothelial transition. These new mechanisms of coronary vessel formation and regeneration open up new possibilities targeting neovascularization for promoting cardiac repair and regeneration. Here, we highlight some recent studies on cellular mechanisms of coronary vessel formation, and discuss the potential impact and significance of the findings on basic research and clinical application for treating ischemic heart disease.