Mechanisms underlying the antiarrhythmic effect of ARumenamide-787 in experimental models of the J wave syndromes and hypothermia

BACKGROUND

Brugada (BrS) and early repolarization syndromes (ERS), the so-called J wave syndromes (JWS), are associated with life-threatening ventricular arrhythmias. Pharmacologic approaches to therapy are currently limited. In this study, we examine the effects of ARumenamide-787 (AR-787) to suppress the electrocardiographic and arrhythmic manifestations of JWS and hypothermia.

METHODS

We studied the effects of AR-787 on INa and IKr in HEK-293 cells stably expressing the α- and β1-subunits of the cardiac (NaV1.5) sodium channel and hERG channel, respectively. In addition, we studied its effect on Ito, INa and ICa in dissociated canine ventricular myocytes along with action potentials and ECG from coronary-perfused right (RV) and left (LV) ventricular wedge preparations. The Ito agonist, NS5806 (5-10 μM), ICa blocker, verapamil (2.5 μM), and INa blocker, ajmaline (2.5 μM), were used to mimic the genetic defects associated with JWS and to induce the electrocardiographic and arrhythmic manifestations of JWS (prominent J waves/ST segment elevation, phase 2 reentry and polymorphic VT/VF) in canine ventricular wedge preparations.

RESULTS

AR-787 (1, 10 and 50 μM) exerted pleiotropic effects on cardiac ion channels. The predominant effect was inhibition of the transient outward current (Ito) and enhancement of the sodium channel current (INa), with lesser effects to inhibit IKr and augment calcium channel current (ICa). AR-787 diminished the electrocardiographic J wave and prevented and/or suppressed all arrhythmic activity in canine RV and LV experimental models of BrS, ERS and hypothermia.

CONCLUSIONS

Our findings point to AR-787 as promising candidate for the pharmacologic treatment of JWS and hypothermia.

Symptom Clusters in Family Caregivers of Hematopoietic Stem Cell Transplantation Recipients: Loneliness as a Risk Factor

A symptom cluster is a group of 2 or more symptoms that occur together and are related to each other. Family caregivers of allogeneic hematopoietic stem cell transplantation (HSCT) recipients experience multiple concurrent symptoms, but the majority of symptom research in this population has focused on assessing and managing individual symptoms. The purpose of this analysis was to determine (1) whether clusters of 5 highly prevalent symptoms (fatigue, sleep disturbance, depression, anxiety, and cognitive impairment) in allogeneic HSCT caregivers could be identified and (2) which caregiver and patient characteristics influence membership in the identified symptom cluster groups. Baseline cross-sectional data were collected from allogeneic HSCT caregivers participating in a randomized controlled trial at the National Institutes of Health Clinical Center. Measures included the Caregiver Reaction Assessment (CRA), Health-Promoting Lifestyle Profile II (HPLP-II), Fatigue Symptom Inventory (MFSI), Pittsburgh Sleep Quality Index (PSQI), and Patient-Reported Outcomes Measurement Information System (PROMIS). Cluster analysis was used to identify symptom clusters, and univariate analyses and multiple logistic regression were performed to identify factors that contribute to symptom clusters. The average age of caregivers (n = 44) was 45.20 ± 15.05 years; primarily white (52.3%) and female (88.6%) and often the spouse/partner of the patient (50.0%). Two symptom cluster groups were identified: low symptom burden (n = 24; 54.5%) and high symptom burden (n = 20; 45.5%). Caregivers with higher levels of loneliness (odds ratio, 1.12; 95% confidence interval, 1.04 to 1.22; P = .004) were more likely to be in the high symptom burden group. This study provides evidence that 5 symptoms commonly found in family caregivers-fatigue, sleep disturbance, depression, anxiety, and cognitive impairment-tend to occur in clusters. Therefore, clinicians should be aware that caregivers with 1 or more of these symptoms may be at higher risk for developing the others, and caregivers reporting high levels of loneliness may be at particular risk. Future research is needed to identify novel interventions that target multiple, co-occurring symptoms. Such interventions also might include components that decrease loneliness. © 2022 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Going virtual during the COVID-19 pandemic: adaptation of a mixed-methods dietary behavior study within a community-based participatory research study of African-American adults at risk for cardiovascular disease

BACKGROUND

Identifying mechanisms to maintain CBPR studies during an infectious disease pandemic is vital. The current paper describes the changes in methods and processes conducted within a CBPR mixed-methods study to a virtual setting during the novel coronavirus (COVID-19) pandemic.

METHOD

The DC Community Organizing for Optimal Culinary Knowledge study with Heart (DC COOKS with Heart) was designed to assess the feasibility of a dietary behavior intervention among African-American adults that are at risk for cardiovascular disease (CVD). The study is under the umbrella of an ongoing CBPR study and community advisory board that facilitates community involvement in study design and promotes ongoing engagement with community members and leaders. The study population for D.C. COOKS with Heart consists of adult African-American individuals who live in two low-resource neighborhoods in Washington, D.C., which were impacted disproportionately by COVID. Eligible study participants who previously participated in the DC CHOC community-based studies were contacted to participate in Phase 1. The quantitative part of the mixed-methods included survey data collection.

RESULTS

Due to the pandemic, the mode of data collection for surveys changed from self-administered face-to-face to internet-based. All virtual study procedures were conducted between March and April, 2021. Anticipated benefits of the virtual setting included participant safety during the pandemic, ease of logistics for participants. Anticipated challenges included administration of electronic devices to participants, research team training, and potential threats to established trust related to the privacy and confidentiality of participants.

CONCLUSION

The transition to a virtual setting for study procedures in a mixed-methods study was conducted successfully in terms of recruitment, retention of participants, and training of research team members. The virtual transition required established and ongoing engagement through the community advisory board and CBPR practices, institutional support through virtual research policies, collaborations with information technology-based teams, and equipment administration for the study.

TRIALS REGISTRATION

NCT04305431 . Registered on March 12, 2020.

Cost-analysis of in-office versus operating room sialendoscopy: Comparison of cost burden and outcomes

PURPOSE

Office-based procedures in otolaryngology are increasingly utilized to increase efficiency, reduce cost, and eliminate risks associated with surgery. Gland-preserving surgical management of sialadenitis and sialolithiasis are often performed in the operating room, although many surgeons are moving this practice to clinic. We aim to determine the difference in patient charges and perioperative outcomes for salivary gland procedures performed in the clinic versus the OR.

METHODS

Retrospective series of patients presenting with sialolithiasis, acute or chronic sialadenitis, and stricture between 2010 and 2019. Demographics, perioperative variables, setting, and charge data were collected.

RESULTS

528 patients underwent operative intervention (n = 427 office, n = 101 OR). Cohort demographics were comparable. Sialolithiasis was the most common presenting diagnosis in both cohorts. Both cohorts had similar rates of complete (p = 0.09) and partial (p = 0.97) response to treatment. A higher percentage of patients in the OR group reported no improvement (21.4 vs 12.2%, p = 0.034). Overall complications were similar (p = 0.582). Mean charges were statistically greater in the OR ($5560.35 OR vs $1298.33 office, p < 0.001). Operative time was significantly reduced in the office group (21.8 min vs 60.85 min, p < 0.001).

CONCLUSIONS

Appropriately selected patients can be successfully treated in outpatient clinic without compromising patient safety or quality while significantly reducing the financial burden to patients and the healthcare system.

Zoonotic potential of a novel bat morbillivirus

Bats are significant reservoir hosts for many viruses with zoonotic potential1. SARS-CoV-2, Ebola virus, and Nipah virus are examples of such viruses that have caused deadly epidemics and pandemics when spilled over from bats into human and animal populations2,3. Careful surveillance of viruses in bats is critical for identifying potential zoonotic pathogens. However, metagenomic surveys in bats often do not result in full-length viral sequences that can be used to regenerate such viruses for targeted characterization4. Here, we identify and characterize a novel morbillivirus from a vespertilionid bat species (Myotis riparius) in Brazil, which we term myotis bat morbillivirus (MBaMV). There are 7 species of morbilliviruses including measles virus (MeV), canine distemper virus (CDV) and rinderpest virus (RPV)5. All morbilliviruses cause severe disease in their natural hosts6–10, and pathogenicity is largely determined by species specific expression of canonical morbillivirus receptors, CD150/SLAMF111 and NECTIN412. MBaMV used Myotis spp CD150 much better than human and dog CD150 in fusion assays. We confirmed this using live MBaMV that was rescued by reverse genetics. Surprisingly, MBaMV replicated efficiently in primary human myeloid but not lymphoid cells. Furthermore, MBaMV replicated in human epithelial cells and used human NECTIN4 almost as well as MeV. Our results demonstrate the unusual ability of MBaMV to infect and replicate in some human cells that are critical for MeV pathogenesis and transmission. This raises the specter of zoonotic transmission of a bat morbillivirus.

Factors That Influence Health-Promoting Behaviors in Cancer Caregivers

OBJECTIVES

To describe cancer caregivers' participation in health-promoting behaviors and to identify factors influencing participation.

SAMPLE & SETTING

129 informal cancer caregivers at the National Institutes of Health Clinical Center.

METHODS & VARIABLES

Cross-sectional survey methodology using Health-Promoting Lifestyle Profile-II (HPLP-II), PROMIS® Global Physical Health, NIH Toolbox Stress and Self-Efficacy, Caregiver Reaction Assessment, and Family Care Inventory Mutuality subscale.

RESULTS

Caregivers reported the highest HPLP-II subscale scores for spirituality and interpersonal relationships and the lowest for physical activity. Caregivers who were older, with lower body mass indices, in better physical health, and with higher self-efficacy and mutuality participated in more health-promoting behaviors. Sixty percent of the caregivers reported that they exercised less since becoming a caregiver, and 47% reported that their diet was worse.

IMPLICATIONS FOR NURSING

Future research is needed to examine novel interventions to increase health-promoting activities in cancer caregivers, and these interventions might be strengthened by including components that focus on increasing self-efficacy and/or improving the strength of the relationship between the caregiver and care recipient.

Acute and chronic fatigue in nurses providing direct patient care and in non-direct care roles: A cross-sectional analysis

Nurses are at risk for work-related fatigue, which can impact their health, well-being, and job readiness. The purpose of this study was to examine the levels, types, and factors associated with fatigue in registered nurses (RNs) in direct patient care (DCRNs) and in non-direct patient care (non-DCRNs) roles. A cross-sectional survey was administered to 313 RNs. Measures included: Multidimensional Fatigue Symptom Inventory, Occupational Fatigue Exhaustion Recovery, Brief COPE, PROMIS® Global Sleep Disturbance, and Job Content Questionnaire. Acute fatigue levels in RNs were similar to those in diseased populations, and nearly 50% reported moderate/high levels of chronic fatigue. DCRNs reported higher levels of acute and chronic fatigue than non-DCRNs, but the differences were small and disappeared when accounting for other factors associated with fatigue including sleep disturbance, job strain, workplace support, maladaptive coping, and especially intershift recovery, which accounted for 20%-41% of fatigue variability. This study suggests that it may not be only nurses providing direct patient care who are at risk for acute and chronic fatigue. Intershift recovery may be particularly important in alleviating acute and chronic fatigue in nurses.

Toward Nonbinary Nuance in Research and Care: Mapping Differences in Gender Affirmation and Transgender Congruence in an Online National U.S. Survey

Purpose: To close gaps in transgender health research, we mapped trends in gender affirmation processes (i.e., social, legal, and psychological transitions) that are unique among nonbinary (NB) transgender adults when compared with transgender women (TW) and transgender men (TM).

Methods: Data were drawn from the Columbia Trans Empowerment Survey (N=707), an online national study conducted between 2014 and 2015 in the United States. We used one-way analysis of variance tests, chi-square tests, Kruskal–Wallis tests, and post hoc analyses to estimate differences in gender affirmation processes and transgender congruence between: (1) NB adults, n=271, 38%; (2) TW, n=291, 41%; and (3) TM, n=145, 21%. We then identified bivariate correlations between variables of interest.

Results: In the full sample (n=707), we found significant positive bivariate correlations between pursuing gender affirmation and transgender congruence. In terms of demographics, NB participants were significantly more likely to be queer (42.1%), polyamorous (25.5%), unemployed (44.8%), and younger (median=22) than TW and TM. They also reported taking significantly fewer gender affirmation processes, with significant differences between the three groups in terms of particular experiences. The NB participants also reported significantly lower rates of transgender congruence, specifically lower appearance congruence though similar gender identity acceptance.

Conclusion: The NB transgender adults in this sample report unique identity-related characteristics, including significantly lower rates of medical/social transition as well as decreased transgender congruence. These data are among the first to describe unique pathways by which NB adults, TW, and TM may pursue gender affirmation and interact with providers as they navigate congruence, transition, and well-being.

Incidentally discovered severe hypercalcaemia from a functioning parathyroid cyst: the limitations of intraoperative parathyroid hormone (IOPTH) monitoring

Parathyroid cysts (PCs) are rare pathologies and are typically non-functional (do not secrete parathyroid hormone (PTH)). The aetiology of PCs is highly debated, and management is complex. We present a unique case of a parathyroid adenoma contained within a functional PC and highlight the limitations of intraoperative PTH monitoring during the surgical resection of functional PCs.

Ovine model of burn wounds grafted with ovine cadaver skin

Shortage in autograft to cover burn wounds involves a frequent use of cadaver skin (CS) as a temporary cover to prevent infection, dehydration and preparation of wounds for subsequent autografting. We aimed to establish an ovine model of burn wound healing using ovine CS (OCS). Quality and efficacy of fresh and frozen OCS overlaid on to excised 3rd degree flame burn wounds in sheep were evaluated in comparison to autograft. Histologically, autografted wounds maintained normal skin structure at different time points. Wounds overlaid with fresh OCS graft showed signs of rejection starting from day 7. At day 14, the epidermis was mostly rejected. The rejection was completed by day 20 with signs of immunoreaction and presence of many immune cells. Frozen OCS was rejected in the same pattern. Immediately prior to grafting, the thickness was comparable between freshly prepared and frozen OCS for 10 or 40 days. Significant reduction in viability was detected in OCS frozen for 40 days. Both fresh or frozen ovine OCS were rejected within 10 days that mimics CS rejection time in humans (∼8.4 days), suggesting that ovine model of burn wound grafted with OCS can successfully be used in burn wound research mimicking clinical scenario.

Factors influencing loneliness in cancer caregivers: A longitudinal study

OBJECTIVE

To describe levels of loneliness in cancer caregivers over a 6 month time period, and to examine factors that influence changes in loneliness in caregivers over time.

METHODS

Prospective, repeated measures design was utilized to examine levels of loneliness and factors that influence loneliness in 129 family caregivers of individuals undergoing cancer treatment at three time points over a 6 month period. Measures included: PROMIS global health and sleep disturbance; NIH Toolbox loneliness, self-efficacy and perceived stress; Family Care Inventory mutuality scale; and Caregiver Reaction Assessment.

RESULTS

Approximately one third (30.2%, n = 39) of the caregivers had high levels of loneliness, and levels of loneliness did not change over the three time points (P = .985). For any given time point, caregivers who were not married (P = .008), not working (P = .027), with worse mental health (P = .015), more perceived-stress (P < .0001), and more caregiver burden (P = .003) reported higher levels of loneliness.

CONCLUSION

This study provides guidance for clinicians attempting to identify at-risk caregivers by confirming the findings of previous research that caregivers with higher burden, stress and in poor mental health are at increased risk for loneliness. This study provides preliminary evidence that continuing to work during the caregiving trajectory may be beneficial to caregivers by reducing levels of loneliness. Future research is needed to confirm these findings and to examine novel interventions to reduce loneliness in cancer caregivers.

Student Satisfaction and Learning Outcomes in Asynchronous Online Lecture Videos

Our study identified online lecture video styles that improved student engagement and satisfaction, while maintaining high learning outcomes in online education. We presented different lecture video styles with standardized material to students and then measured learning outcomes and satisfaction with a survey and summative assessment. We created an iterative qualitative coding scheme, "coding online asynchronous lectures" (COAL), to analyze open-ended student survey responses. Our results reveal that multimedia learning can be satisfying and effective. Students have strong preferences for certain video styles despite their equal learning outcomes, with the Learning Glass style receiving the highest satisfaction ratings. Video styles that were described as impersonal and unfamiliar were rated poorly, while those that were described as personal and engaging and evoked positive affective responses were rated highly. The students in our study rated lecture video styles that aligned with Mayer's multimedia learning principles as highly satisfying, indicating that student feedback can be a valuable resource for course designers to consider as they design their own online courses. Finally, we provide guidelines for creating engaging, effective, and satisfying asynchronous lecture videos to support establishment of best practices in online instruction.

Discrimination, work outcomes, and mental health among women of color: The protective role of womanist attitudes

With a sample of employed women of color (N = 276), we tested the associations of sexist and racist discrimination with poor work outcomes (job-related burnout and turnover intentions) and mental health outcomes (i.e., psychological distress). Drawing from the Theory of Work Adjustment, Organizational Support Theory, and scholarship on discrimination, we tested perceived person-organization (P-O) fit, perceived organizational support, and self-esteem as mediators of the associations of workplace discrimination with the outcomes. Based on intersectionality scholarship, womanist attitudes were tested as a moderator. Participants provided cross-sectional data via an online survey. Latent variable structural equation modeling results indicated that a second-order latent workplace discrimination variable yielded better fit to the data than modeling sexist and racist discrimination separately. Workplace discrimination was directly and indirectly (via the mediating role of self-esteem) associated with higher psychological distress. Furthermore, workplace discrimination was indirectly associated with poor work outcomes through the mediating roles of perceived P-O fit, perceived organizational support, and self-esteem. Last, moderation analyses indicated that higher womanist attitudes weakened the direct association of workplace discrimination with psychological distress. (PsycINFO Database Record

Heterosexism, Racism, and the Mental Health of Sexual Minority People of Color

In the present study, we examined the additive and multiplicative associations of heterosexist discrimination, racist discrimination, internalized heterosexism, and internalized racism with psychological distress and well-being in 318 sexual minority People of Color. We tested multiplicative associations via two sets of interactions: cross-oppression (Heterosexist Discrimination × Internalized Racism, Racist Discrimination × Internalized Heterosexism) and same-oppression (Heterosexist Discrimination × Internalized Heterosexism, Racist Discrimination × Internalized Racism). Consistent with the additive perspective, heterosexist discrimination and internalized racism were uniquely positively associated with distress, whereas internalized heterosexism and internalized racism were uniquely negatively associated with well-being. The Heterosexist Discrimination × Internalized Racism and Racist Discrimination × Internalized Racism interactions were significant in relation to both distress and well-being. Internalized racism was associated with significantly poorer mental health until heterosexist and racist discrimination reached high levels. We discuss the implications of our findings for research and practice with sexual minority People of Color.

Reduced Postburn Hypertrophic Scarring and Improved Physical Recovery With Yearlong Administration of Oxandrolone and Propranolol

BACKGROUND

Massive burns induce a hypermetabolic response that leads to total body wasting and impaired physical and psychosocial recovery. The administration of propranolol or oxandrolone positively affects postburn metabolism and growth. The combined administration of oxandrolone and propranolol (OxProp) for 1 year restores growth in children with large burns. Here, we investigated whether the combined administration of OxProp for 1 year would reduce scarring and improve quality of life compared with control.

STUDY DESIGN

Children with large burns (n = 480) were enrolled into this institutional review board-approved study; patients were randomized to control (n = 226) or administration of OxProp (n = 126) for 1 year postburn. Assessments were conducted at discharge and 6, 12, and 24 months postburn. Scar biopsies were obtained for histology. Physical scar assessments and patient reported outcome measures of physical and psychosocial function were obtained.

RESULTS

Reductions in cellularity, vascular structures, inflammation, and abnormal collagen (P < 0.05) occurred in OxProp-treated scars. With OxProp, scar severity was attenuated and pliability increased (both P < 0.05). Analyses of patient-reported outcomes showed improved general and emotional health within the OxProp-treated group (P < 0.05).

CONCLUSIONS

Here, we have shown improvements in objective and subjective measures of scarring and an increase in overall patient-reported physical function. The combined administration of OxProp for up to a year after burn injury should be considered for the reduction of postburn scarring and improvement of long-term psychosocial outcomes in children with massive burns.

NNT is a key regulator of adrenal redox homeostasis and steroidogenesis in male mice

Nicotinamide nucleotide transhydrogenase, NNT, is a ubiquitous protein of the inner mitochondrial membrane with a key role in mitochondrial redox balance. NNT produces high concentrations of NADPH for detoxification of reactive oxygen species by glutathione and thioredoxin pathways. In humans, NNT dysfunction leads to an adrenal-specific disorder, glucocorticoid deficiency. Certain substrains of C57BL/6 mice contain a spontaneously occurring inactivating Nnt mutation and display glucocorticoid deficiency along with glucose intolerance and reduced insulin secretion. To understand the underlying mechanism(s) behind the glucocorticoid deficiency, we performed comprehensive RNA-seq on adrenals from wild-type (C57BL/6N), mutant (C57BL/6J) and BAC transgenic mice overexpressing Nnt (C57BL/6J^BAC). The following results were obtained. Our data suggest that Nnt deletion (or overexpression) reduces adrenal steroidogenic output by decreasing the expression of crucial, mitochondrial antioxidant (Prdx3 and Txnrd2) and steroidogenic (Cyp11a1) enzymes. Pathway analysis also revealed upregulation of heat shock protein machinery and haemoglobins possibly in response to the oxidative stress initiated by NNT ablation. In conclusion, using transcriptomic profiling in adrenals from three mouse models, we showed that disturbances in adrenal redox homeostasis are mediated not only by under expression of NNT but also by its overexpression. Further, we demonstrated that both under expression or overexpression of NNT reduced corticosterone output implying a central role for it in the control of steroidogenesis. This is likely due to a reduction in the expression of a key steroidogenic enzyme, Cyp11a1, which mirrored the reduction in corticosterone output.

Prestin as an Otologic Biomarker of Cisplatin Ototoxicity in a Guinea Pig Model

Objective

To evaluate (1) whether changes in serum prestin aid in early detection of cisplatin ototoxicity, (2) the role of diltiazem as an otoprotectant, and (3) whether prestin levels are sensitive to effects of diltiazem.

Study Design

Experimental animal study.

Setting

Translational research laboratory.

Subjects

Twenty female guinea pigs.

Methods

Two groups of 10 guinea pigs were used. The relationship between serum prestin levels and auditory brainstem response (ABR) thresholds was compared between the groups. All animals had baseline blood draws and ABR thresholds recorded prior to cisplatin administration. Intraperitoneal cisplatin bolus (8 mg/kg) was administered followed by 5 consecutive days of intratympanic (IT) diltiazem (2 mg/kg) or sham IT-saline injection. Serum prestin levels and ABR thresholds were measured at days 1, 2, 3, 7, and 14 postcisplatin.

Results

In sham, IT-saline–treated animals, mean prestin levels were elevated above baseline on days 1 to 7. The prestin levels were significantly elevated from baseline on day 1 ( P < .001), while significant ABR threshold elevations did not occur until day 2 ( P = .028) for click-evoked ABRs and day 3 ( P = .041) for tones. In diltiazem-treated animals, prestin levels were not elevated above baseline but ABR thresholds were elevated on days 1 to 3. However, the thresholds returned toward baseline on days 7 and 14.

Conclusion

Changes in serum prestin levels were detectable prior to shifts in ABR thresholds in a guinea pig cisplatin ototoxicity model. These changes did not occur in diltiazem-treated animals. Prestin may serve as a biomarker of cochlear injury that is sensitive to therapeutic interventions in cisplatin ototoxicity.

Characterizing sleep spindles in 11,630 individuals from the National Sleep Research Resource

Sleep spindles are characteristic electroencephalogram (EEG) signatures of stage 2 non-rapid eye movement sleep. Implicated in sleep regulation and cognitive functioning, spindles may represent heritable biomarkers of neuropsychiatric disease. Here we characterize spindles in 11,630 individuals aged 4 to 97 years, as a prelude to future genetic studies. Spindle properties are highly reliable but exhibit distinct developmental trajectories. Across the night, we observe complex patterns of age- and frequency-dependent dynamics, including signatures of circadian modulation. We identify previously unappreciated correlates of spindle activity, including confounding by body mass index mediated by cardiac interference in the EEG. After taking account of these confounds, genetic factors significantly contribute to spindle and spectral sleep traits. Finally, we consider topographical differences and critical measurement issues. Taken together, our findings will lead to an increased understanding of the genetic architecture of sleep spindles and their relation to behavioural and health outcomes, including neuropsychiatric disorders.

Sleep patterns vary and are associated with health and disease. Here Purcell et al characterize sleep spindle activity in 11,630 individuals and describe age-related changes, genetic influences, and possible confounding effects, serving as a resource for further understanding the physiology of sleep.

Survivors of childhood leukaemia treated with haematopoietic stem cell transplantation and total body irradiation should undergo screening for diabetes by oral glucose tolerance tests

AIMS

Childhood cancer survivors treated with haematopoietic stem cell transplantation (HSCT) and total body irradiation are at an increased risk of developing diabetes early in life due to insulin resistance and β-cell dysfunction, but the optimal screening method is unknown. The National Institute for Health and Care Excellence guidelines for community diabetes screening recommend using fasting glucose ≥ 7 mmol/l and/or HbA1c ≥ 48 mmol/mol (6.5%) for diagnosis and, fasting glucose 5.5-6.9 mmol/l or HbA1c 42-47 mmol/mol (6-6.5%) to indicate high risk. This study aimed to evaluate the sensitivities of fasting glucose and HbA1c in the diagnosis of diabetes and impaired glucose tolerance in childhood HSCT survivors.

METHOD

The patients were 35 (male = 19) HSCT survivors from a single UK centre under follow-up from 2006 to 2013. Patients had a median age (range) of 19.2 (13.1-26.2) years and had been treated for acute lymphoblastic (n = 31) or myeloid (n = 4) leukaemia when aged 7.8 (2.4-16.7) years. The outcome measures were oral glucose tolerance test (OGTT), fasting glucose and HbA1c .

RESULTS

OGTT identified 6 patients with diabetes (120-min glucose ≥ 11.1 mmol/l), 12 with impaired glucose tolerance (120-min glucose 7.8-11.0 mmol/l) and 2 with impaired fasting glucose (≥ 7 mmol/l). Fasting glucose ≥ 7 mmol/l or HbA1c ≥ 48 mmol/mol identified two of the six patients with diabetes diagnosed on OGTT. Fasting glucose ≥ 5.5 mmol/l and HbA1c ≥ 42 mmol/mol identified three and two patients, respectively, with diabetes. Only 1 of 12 patients with impaired glucose tolerance had a fasting glucose ≥ 5.5 mmol/l and none had HbA1c ≥ 42 mmol/mol (≥ 6%).

CONCLUSIONS

The fasting glucose and HbA1c cut-offs used in UK population screening only identified one-third of HSCT survivors with diabetes and do not identify those at risk. Diabetes screening in HSCT survivors requires standard OGTTs.

Identification and Characterization of Influenza Virus Entry Inhibitors through Dual Myxovirus High-Throughput Screening

Influenza A virus (IAV) infections cause major morbidity and mortality, generating an urgent need for novel antiviral therapeutics. We recently established a dual myxovirus high-throughput screening protocol that combines a fully replication-competent IAV-WSN strain and a respiratory syncytial virus reporter strain for the simultaneous identification of IAV-specific, paramyxovirus-specific, and broad-spectrum inhibitors. In the present study, this protocol was applied to a screening campaign to assess a diverse chemical library with over 142,000 entries. Focusing on IAV-specific hits, we obtained a hit rate of 0.03% after cytotoxicity testing and counterscreening. Three chemically distinct hit classes with nanomolar potency and favorable cytotoxicity profiles were selected. Time-of-addition, minigenome, and viral entry studies demonstrated that these classes block hemagglutinin (HA)-mediated membrane fusion. Antiviral activity extends to an isolate from the 2009 pandemic and, in one case, another group 1 subtype. Target identification through biolayer interferometry confirmed binding of all hit compounds to HA. Resistance profiling revealed two distinct escape mechanisms: primary resistance, associated with reduced compound binding, and secondary resistance, associated with unaltered binding. Secondary resistance was mediated, unusually, through two different pairs of cooperative mutations, each combining a mutation eliminating the membrane-proximal stalk N-glycan with a membrane-distal change in HA1 or HA2. Chemical synthesis of an analog library combined with in silico docking extracted a docking pose for the hit classes. Chemical interrogation spotlights IAV HA as a major druggable target for small-molecule inhibition. Our study identifies novel chemical scaffolds with high developmental potential, outlines diverse routes of IAV escape from entry inhibition, and establishes a path toward structure-aided lead development.

IMPORTANCE

This study is one of the first to apply a fully replication-competent third-generation IAV reporter strain to a large-scale high-throughput screen (HTS) drug discovery campaign, allowing multicycle infection and screening in physiologically relevant human respiratory cells. A large number of potential druggable targets was thus chemically interrogated, but mechanistic characterization, positive target identification, and resistance profiling demonstrated that three chemically promising and structurally distinct hit classes selected for further analysis all block HA-mediated membrane fusion. Viral escape from inhibition could be achieved through primary and secondary resistance mechanisms. In silico docking predicted compound binding to a microdomain located at the membrane-distal site of the prefusion HA stalk that was also previously suggested as a target site for chemically unrelated HA inhibitors. This study identifies an unexpected chemodominance of the HA stalk microdomain for small-molecule inhibitors in IAV inhibitor screening campaigns and highlights a novel mechanism of cooperative resistance to IAV entry blockers.

Structure-guided design of small-molecule therapeutics against RSV disease

INTRODUCTION

In the United States, respiratory syncytial virus (RSV) is responsible for the majority of infant hospitalizations resulting from viral infections, as well as a leading source of pneumonia and bronchiolitis in young children and the elderly. In the absence of vaccine prophylaxis or an effective antiviral for improved disease management, the development of novel anti-RSV therapeutics is critical. Several advanced drug development campaigns of the past decade have focused on blocking viral infection. These efforts have returned a chemically distinct panel of small-molecule RSV entry inhibitors, but binding sites and molecular mechanism of action appeared to share a common mechanism, resulting in comprehensive cross-resistance and calling for alternative druggable targets such as viral RNA-dependent RNA-polymerase complex. Areas Covered: In this review, the authors discuss the current status of the mechanism of action of RSV entry inhibitors. They also provide the recent structural insight into the organization of the polymerase complex that have revealed novel drug targets sites, and outline a path towards the discovery of next-generation RSV therapeutics. Expert opinion: Considering the tremendous progress experienced in our structural understanding of RSV biology in recent years and encouraging early results of a nucleoside analog inhibitor in clinical trials, there is high prospect that new generations of much needed effective anti-RSV therapeutics will become available for clinical use in the foreseeable future.

Top 10 Facts You Need to Know About Synthetic Cannabinoids: Not So Nice Spice

In April and May 2015, the state of Mississippi experienced an unprecedented outbreak of severe reactions to the drug commonly referred to as "Spice." After numerous calls to the Poison Control Center, it became clear that health care providers were largely unfamiliar with the category of synthetic cannabinoids. This review article briefly highlights cannabinoid effects, chemical characteristics, and treatment for this often-dangerous category of drugs of abuse.

Mental Schemas Hamper Memory Storage of Goal-Irrelevant Information

Mental schemas exert top-down control on information processing, for instance by facilitating the storage of schema-related information. However, given capacity-limits and competition in neural network processing, schemas may additionally exert their effects by suppressing information with low momentary relevance. In particular, when existing schemas suffice to guide goal-directed behavior, this may actually reduce encoding of the redundant sensory input, in favor of gaining efficiency in task performance. The present experiment set out to test this schema-induced shallow encoding hypothesis. Our approach involved a memory task in which faces had to be coupled to homes. For half of the faces the responses could be guided by a pre-learned schema, for the other half of the faces such a schema was not available. Memory storage was compared between schema-congruent and schema-incongruent items. To characterize putative schema effects, memory was assessed both with regard to visual details and contextual aspects of each item. The depth of encoding was also assessed through an objective neural measure: the parietal old/new ERP effect. This ERP effect, observed between 500–800 ms post-stimulus onset, is thought to reflect the extent of recollection: the retrieval of a vivid memory, including various contextual details from the learning episode. We found that schema-congruency induced substantial impairments in item memory and even larger ones in context memory. Furthermore, the parietal old/new ERP effect indicated higher recollection for the schema-incongruent than the schema-congruent memories. The combined findings indicate that, when goals can be achieved using existing schemas, this can hinder the in-depth processing of novel input, impairing the formation of perceptually detailed and contextually rich memory traces. Taking into account both current and previous findings, we suggest that schemas can both positively and negatively bias the processing of sensory input. An important determinant in this matter is likely related to momentary goals, such that mental schemas facilitate memory processing of goal-relevant input, but suppress processing of goal-irrelevant information.

Blocking Respiratory Syncytial Virus Entry: A Story with Twists

Respiratory syncytial virus (RSV) is responsible for majority of infant hospitalizations due to viral infections. Despite its clinical importance, no vaccine against RSV or effective antiviral therapy is available. Several structural classes of small-molecule RSV entry inhibitor have been described and one compound has advanced to clinical testing. Mutations in either one of two resistance hot spots in the F protein mediate unusual pan-resistance to all of these inhibitor classes. Based on the biochemical characterization of resistant viruses and structural insight into the RSV F trimer, we propose a kinetic escape model as the origin of pan-resistance. Since a resistant RSV remained pathogenic in the mouse model, pan-resistance mutations could emerge rapidly in circulating RSV strains. We evaluate clinical implications and discuss consequences for the design of future RSV drug discovery campaigns.

Chemokine CXCL1-Mediated Neutrophil Trafficking in the Lung: Role of CXCR2 Activation

The chemokine CXCL1 and its receptor CXCR2 play a crucial role in host immune response by recruiting and activating neutrophils for microbial killing at the tissue site. Dysregulation in this process has been implicated in collateral tissue damage causing disease. CXCL1 reversibly exists as monomers and dimers, and it has been proposed that distinct monomer and dimer activities and the monomer-dimer equilibrium regulate the neutrophil function. However, the molecular mechanisms linking the CXCL1/CXCR2 axis and the neutrophil 'beneficial' and 'destructive' phenotypes are not known. In this study, we characterized neutrophil trafficking and its consequence in the mouse lung by the CXCL1 wild type (WT), which exists as monomers and dimers, and by a nondissociating dimer. Whereas the WT, compared to the dimer, was more active at low doses, both the WT and the dimer elicited a large neutrophil efflux at high doses. Importantly, robust neutrophil recruitment elicited by the WT or dimer was not detrimental to lung tissue integrity and, further, could not be correlated to surface CXCR2 levels. We conclude that the CXCL1 monomer-dimer distribution and receptor interactions are highly coupled and regulate neutrophil trafficking and that injury in the context of disease is a consequence of inappropriate CXCR2 activation at the target tissue and not due to mechanical forces exerted by neutrophils during recruitment.

Development and Pilot Testing of the Eating4two Mobile Phone App to Monitor Gestational Weight Gain

Background

The number of pregnant women with a body mass index (BMI) of 30kg/m² or more is increasing, which has important implications for antenatal care. Various resource-intensive interventions have attempted to assist women in managing their weight gain during pregnancy with limited success. A mobile phone app has been proposed as a convenient and cost-effective alternative to face-to-face interventions.

Objective

This paper describes the process of developing and pilot testing the Eating4Two app, which aims to provide women with a simple gestational weight gain (GWG) calculator, general dietary information, and the motivation to achieve a healthy weight gain during pregnancy.

Methods

The project involved the development of app components, including a graphing function that allows the user to record their weight throughout the pregnancy and to receive real-time feedback on weight gain progress and general information on antenatal nutrition. Stakeholder consultation was used to inform development. The app was pilot tested with 10 pregnant women using a mixed method approach via an online survey, 2 focus groups, and 1 individual interview.

Results

The Eating4Two app took 7 months to develop and evaluate. It involved several disciplines--including nutrition and dietetics, midwifery, public health, and information technology--at the University of Canberra. Participants found the Eating4Two app to be a motivational tool but would have liked scales or other markers on the graph that demonstrated exact weight gain. They also liked the nutrition information; however, many felt it should be formatted in a more user friendly way.

Conclusions

The Eating4Two app was viewed by participants in our study as an innovative support system to help motivate healthy behaviors during pregnancy and as a credible resource for accessing nutrition-focused information. The feedback provided by participants will assist with refining the current prototype for use in a clinical intervention trial.

The paramyxovirus polymerase complex as a target for next-generation anti-paramyxovirus therapeutics

The paramyxovirus family includes major human and animal pathogens, including measles virus, mumps virus, and human respiratory syncytial virus (RSV), as well as the emerging zoonotic Hendra and Nipah viruses. In the U.S., RSV is the leading cause of infant hospitalizations due to viral infectious disease. Despite their clinical significance, effective drugs for the improved management of paramyxovirus disease are lacking. The development of novel anti-paramyxovirus therapeutics is therefore urgently needed. Paramyxoviruses contain RNA genomes of negative polarity, necessitating a virus-encoded RNA-dependent RNA polymerase (RdRp) complex for replication and transcription. Since an equivalent enzymatic activity is absent in host cells, the RdRp complex represents an attractive druggable target, although structure-guided drug development campaigns are hampered by the lack of high-resolution RdRp crystal structures. Here, we review the current structural and functional insight into the paramyxovirus polymerase complex in conjunction with an evaluation of the mechanism of activity and developmental status of available experimental RdRp inhibitors. Our assessment spotlights the importance of the RdRp complex as a premier target for therapeutic intervention and examines how high-resolution insight into the organization of the complex will pave the path toward the structure-guided design and optimization of much-needed next-generation paramyxovirus RdRp blockers.