Evaluation of AAV Capsids and Delivery Approaches for Hereditary Hemorrhagic Telangiectasia Gene Therapy.

Nosebleeds and intracranial hemorrhage from brain arteriovenous malformations (bAVMs) are among the most devastating symptoms of patients with hereditary hemorrhagic telangiectasis (HHT). All available managements have limitations. We showed that intravenous (i.v.) delivery of soluble Feline McDonough Sarcoma (FMS)-related tyrosine kinase 1 using an adeno-associated viral vector (AAV9-sFLT1) reduced bAVM severity of endoglin deficient mice. However, minor liver inflammation and growth arrest in young mice were observed. To identify AAV variants and delivery methods that can best transduce brain and nasal tissue with an optimal transduction profile, we compared 3 engineered AAV capsids (AAV.cc47, AAV.cc84, and AAV1RX) with AAV9. A single-stranded CBA promoter driven tdTomato transgene was packaged in these capsids and delivered i.v. or intranasally (i.n.) to wild-type mice. A CMV promoter driven Alk1 transgene was packaged into AAV.cc84 and delivered to PdgfbiCre;Alk1f/f mice through i.v. followed by bAVM induction. Transduced cells in organs, vessel density, abnormal vessels in the bAVMs, and liver inflammation were analyzed histologically. Liver and kidney function were measured enzymatically. Compared to other viral vectors, AAV.cc84, after i.v. delivery, transduced a high percentage of brain endothelial cells (ECs) and few hepatocytes; whereas after i.n. delivery, AAV.cc84 transduced ECs and perivascular cells in the brain, and ECs, epithelial cells, and muscles in the nose with minimum hepatocyte transduction. No changes to liver or kidney function were detected. The delivery of AAV.cc84-Alk1 through i.v. to PdgfbiCre;Alk1f/f mice reduced bAVM severity. In summary, we propose that AAV.cc84-Alk1 is a promising candidate for developing gene therapy in HHT patients.

Evaluation of Aav Capsids and Delivery Approaches for Hereditary Hemorrhagic Telangiectasia Gene Therapy.

Nosebleeds and intracranial hemorrhage from brain arteriovenous malformations (bAVMs) are among the most devastating symptoms of patients with hereditary hemorrhagic telangiectasis (HHT). All available managements have limitations. We showed that intravenous delivery of soluble FMS-related tyrosine kinase 1 using an adeno-associated viral vector (AAV9-sFLT1) reduced bAVM severity of endoglin deficient mice. However, minor liver inflammation and growth arrest in young mice were observed. To identify AAV variants and delivery methods that can best transduce brain and nasal tissue with an optimal transduction profile, we compared 3 engineered AAV capsids (AAV.cc47, AAV.cc84 and AAV1RX) with AAV9. A single-stranded CBA promoter driven tdTomato transgene was packaged in these capsids and delivered intravenously (i.v.) or intranasally (i.n.) to wild-type mice. A CMV promoter driven Alk1 transgene was packaged into AAV.cc84 and delivered to PdgfbiCre;Alk1 f/f mice through i.v. injection followed by brain AVM induction. Transduced cells in different organs, vessel density and abnormal vessels in the bAVMs, and liver inflammation were analyzed histologically. Liver and kidney function were measured enzymatically. Compared to other viral vectors, AAV.cc84, after i.v. delivery, transduced a high percentage of brain ECs and few hepatocytes; whereas after i.n. delivery, AAV.cc84 transduced ECs and perivascular cells in the brain, and ECs, epithelial cells, and skeletal muscles in the nose with minimum hepatocyte transduction. No changes to liver or kidney function were detected. Delivery of AAV.cc84-Alk1 through i.v. to PdgfbiCre;Alk1 f/f mice reduced bAVM severity. In summary, we propose that AAV.cc84-Alk1 is a promising candidate for developing gene therapy in HHT patients.

Increased Collagen I/Collagen III Ratio Is Associated with Hemorrhage in Brain Arteriovenous Malformations in Human and Mouse.

Background: The increase in the collagen I (COL I)/COL III ratio enhances vessel wall stiffness and renders vessels less resistant to blood flow and pressure changes. Activated microglia enhance inflammation-induced fibrosis. Hypotheses: The COL I/COL III ratio in human and mouse brain arteriovenous malformations (bAVMs) is associated with bAVM hemorrhage, and the depletion of microglia decreases the COL I/COL III ratio and hemorrhage. Method: COL I, COL III, and hemorrhages were analyzed in 12 human bAVMs and 6 control brains, and mouse bAVMs induced in three mouse lines with activin receptor-like kinase 1 (n = 7) or endoglin (n = 7) deleted in the endothelial cells or brain focally (n = 5). The controls for the mouse study were no-gene-deleted litter mates. Mouse bAVMs were used to test the relationships between the Col I/Col III ratio and hemorrhage and whether the transient depletion of microglia reduces the Col I/Col III ratio and hemorrhage. Results: The COL I/COL III ratio was higher in the human and mouse bAVMs than in controls. The microhemorrhage in mouse bAVMs was positively correlated with the Col I/Col III ratio. Transient depletion of microglia reduced the Col I/Col III ratio and microhemorrhage. Conclusions: The COL I/COL III ratio in the bAVMs was associated with bAVM hemorrhage. The depletion of microglia reduced the bAVM Col I/Col III ratio and hemorrhage.

Potential for GPT Technology to Optimize Future Clinical Decision-Making Using Retrieval-Augmented Generation.

Advancements in artificial intelligence (AI) provide many helpful tools for healthcare, one of which includes AI chatbots that use natural language processing to create humanlike, conversational dialog. These chatbots have general cognitive skills and are able to engage with clinicians and patients to discuss patients' health conditions and what they may be at risk for. While chatbot engines have access to a wide range of medical texts and research papers, they currently provide high-level, generic responses and are limited in their ability to provide diagnostic guidance and clinical advice to patients on an individual level. The essay discusses the use of retrieval-augmented generation (RAG), which can be used to improve the specificity of user-entered prompts and thereby enhance the detail in AI chatbot responses. By embedding more recent clinical data and trusted medical sources, such as clinical guidelines, into the chatbot models, AI chatbots can provide more patient-specific guidance, faster diagnoses and treatment recommendations, and greater improvement of patient outcomes.

GPT Technology to Help Address Longstanding Barriers to Care in Free Medical Clinics.

The implementation of technology in healthcare has revolutionized patient-centered decision making by providing contextualized information about a patient's healthcare journey, leading to increased efficiency (Keyworth et al. in BMC Med Inform Decis Mak 18:93, 2018, https://doi.org/10.1186/s12911-018-0661-3 ). Artificial intelligence has been integrated within Electronic Health Records (EHR) to prompt screenings or diagnostic tests based on a patient's holistic health profile. While larger hospitals have already widely adopted these technologies, free clinics hold lower utilization of these advanced capability EHRs. The patient population at a free clinic faces a multitude of factors that limits their access to comprehensive care, thus requiring necessary efforts and measures to close the gap in healthcare disparities. Emerging Artificial Intelligence (AI) technology, such as OpenAI's ChatGPT, GPT-4, and other large language models (LLMs) have remarkable potential to improve patient care outcomes, promote health equity, and enhance comprehensive and holistic care in resource-limited settings. This paper aims to identify areas in which integrating these LLM AI advancements into free clinics operations can optimize and streamline healthcare delivery to underserved patient populations. This paper also identifies areas of improvements in GPT that are necessary to deliver those services.

Antagonizing the irreversible thrombomodulin-initiated proteolytic signaling alleviates age-related liver fibrosis via senescent cell killing.

Cellular senescence is a stress-induced, stable cell cycle arrest phenotype which generates a pro-inflammatory microenvironment, leading to chronic inflammation and age-associated diseases. Determining the fundamental molecular pathways driving senescence instead of apoptosis could enable the identification of senolytic agents to restore tissue homeostasis. Here, we identify thrombomodulin (THBD) signaling as a key molecular determinant of the senescent cell fate. Although normally restricted to endothelial cells, THBD is rapidly upregulated and maintained throughout all phases of the senescence program in aged mammalian tissues and in senescent cell models. Mechanistically, THBD activates a proteolytic feed-forward signaling pathway by stabilizing a multi-protein complex in early endosomes, thus forming a molecular basis for the irreversibility of the senescence program and ensuring senescent cell viability. Therapeutically, THBD signaling depletion or inhibition using vorapaxar, an FDA-approved drug, effectively ablates senescent cells and restores tissue homeostasis in liver fibrosis models. Collectively, these results uncover proteolytic THBD signaling as a conserved pro-survival pathway essential for senescent cell viability, thus providing a pharmacologically exploitable senolytic target for senescence-associated diseases.

Effects of a nurse-led Tai Chi programme on improving quality of life, mental wellbeing, and physical function of women with breast cancer: Protocol for a randomized controlled trial.

OBJECTIVES: Quality of life, mental wellbeing, and physical function deteriorate among women with breast cancer. Tai Chi is a moderate form of exercise that may be effective in improving the mental and physical wellbeing, therefore, the quality of life of women with breast cancer. This protocol paper outlines a trial to determine the therapeutic effects of a Tai Chi programme on breast cancer management. METHODS: The study will be an interventional, single-blind, double-armed, randomized, and controlled trial involving a 12-week Tai Chi programme for women with breast cancer. Forty participants aged 18 years and above who are diagnosed with breast cancer from the general community will be recruited. All participants will be randomized to either a Tai Chi programme or a waiting list control group. The Tai Chi programme will involve 12 weeks of group Tai Chi sessions, with 45 min per session, twice a week. The primary outcome will be potential improvements to the quality of life, and secondary outcomes will be potential improvements in mental wellbeing (anxiety and depression), and physical function (pain, flexibility, obesity, and vital signs). These outcomes will be assessed via self-administered online assessments and physical examinations pre-and post-intervention. Linear mixed modelling will be used to assess changes in outcomes. DISCUSSION AND DISSEMINATION: Tai Chi is a safe, easy to learn, inexpensive, and low-intensity exercise with increasing popularity worldwide. If the intervention improves the quality of life in women with breast cancer, this study will build research capacity and increase awareness of the potential for Tai Chi to empower patients and engage them in self-management of breast cancer symptoms. Research findings will be disseminated to the public, health professionals, researchers, and healthcare providers through conference presentations, lay summaries, and peer-reviewed publications.

Nonunion Risk Assessment in Foot and Ankle Surgery: Proposing a Predictive Risk Assessment Model.

BACKGROUND: Nonunion risk factor identification and modification are subjective. We describe and validate a predictive nonunion risk factor model to identify foot and ankle operative patients at risk for nonunion. MATERIALS AND METHODS: One hundred international experts in foot and ankle surgery were surveyed. Nineteen nonunion risk factors were stratified into 3 categories: more significant than, as significant as, and less significant than smoking 1 pack per day. A nonunion risk assessment model was developed by assigning a weighted score to each risk factor, based on its mean score from the survey. A total nonunion risk (TNR) score was calculated for individual patients. It was retrospectively validated in 2 patient cohorts from a single center's prospectively collected end-stage ankle arthritis patient database: 22 cases of ankle and/or hindfoot fusion nonunion and 40 sex- and procedure-matched controls with bony fusion. Analyses included descriptive statistics, logistic regression, and univariate and multivariate linear regression models. RESULTS: The mean TNR score was 6.6 ± 5.6 in controls and 13.5 ± 8.2 in the nonunion group (P < .001). Data showed excellent intraobserver and interobserver correlation coefficients. In a logistic regression model, the risk of nonunion exceeded 9% with a TNR score greater than or equal to 10. Multivariate linear regression analysis, adjusted for age and sex, suggested that lack of fusion site stability and obesity (body mass index greater than 30) were significantly predictive of nonunion. CONCLUSION: The nonunion risk assessment model provides a reliable, sensitive, and specific method for predicting nonunion based on objective patient assessment. Orthopaedic patients at risk for nonunion could benefit from targeted intervention. LEVEL OF EVIDENCE: Level IV, retrospective observational study.

Tensile properties of craniofacial tendons in the mature and aged zebrafish.

The zebrafish Danio rerio is a powerful model for the study of development, regenerative biology, and human disease. However, the analysis of load-bearing tissues such as tendons and ligaments has been limited in this system. This is largely due to technical limitations that preclude accurate measurement of their mechanical properties. Here, we present a custom tensile testing system that applies nano-Newton scale forces to zebrafish tendons as small as 1 mm in length. Tendon properties were remarkably similar to mammalian tendons, including stress-strain nonlinearity and a linear modulus (515 ± 152 MPa) that aligned closely with mammalian data. Additionally, a simple exponential constitutive law used to describe tendon mechanics was successfully fit to zebrafish tendons; the associated material constants agreed with literature values for mammalian tendons. Finally, mature and aged zebrafish comparisons revealed a significant decline in mechanical function with age. Based on the exponential constitutive model, age-related changes were primarily caused by a reduction in nonlinearity (e.g., changes in collagen crimp or fiber recruitment). These findings demonstrate the utility of zebrafish as a model to study tendon biomechanics in health and disease. Moreover, these findings suggest that tendon mechanical behavior is highly conserved across vertebrates.

The use of multimedia as an adjunct to the informed consent process for Morton's neuroma resection surgery.

BACKGROUND: The purpose of this study was to assess if a computer-based multimedia education module (MEM) improved patients' comprehension when used as an adjunct to the standard verbal consent process for Morton's neuroma resection surgery. METHODS: Nineteen patients (15 females and 4 males) considered candidates for Morton's neuroma resection surgery were prospectively recruited. A standardized verbal discussion was had with each patient regarding risks and benefits of surgery, alternative treatments, and the usual postoperative course. Patient understanding was then assessed with a questionnaire. Each patient subsequently viewed the MEM and the questionnaire was repeated. Patients also rated ease of understanding and satisfaction with both methods of patient education. RESULTS: Patients answered a significantly greater proportion of correct answers after viewing the MEM module (85%), compared to verbal discussion alone (61%) (P = .002). Patients rated both the ease of understanding of the module and amount of information provided by the module as a mean of 9.3 cm on a 10 cm Visual Analog Scale (VAS). The majority of patients (76%) rated the multimedia tool as having answered their questions about surgery as well or better than the treating surgeon. CONCLUSION: An interactive multimedia educational tool was a useful adjunct to the informed consent process for patients considering Morton's neuroma resection surgery. LEVELS OF EVIDENCE: Level II, prospective cohort study.

Differences in the perceived impact of sleep deprivation among surgical and non-surgical residents.

OBJECTIVE: Resident work hour restrictions have been mandated in the USA largely out of concern that sleep deprivation compromises doctor performance and patient care. However, individuals' ability to recognise the effects of sleep deprivation has not been studied in medical education. We examined the perceived impact of sleep deprivation among different groups of postgraduate medical trainees. METHODS: A survey addressing work hours, sleepiness and daily functioning was mailed to all residents in the internal medicine, surgery and psychiatry programmes at the University of Toronto who were working at 6 different teaching hospitals. The mailing included the Epworth Sleepiness Scale (ESS), measuring acute sleepiness, and a new Sleep Deprivation Impact (SDI) scale, consisting of 12 items designed to measure the perceived impact of sleep deprivation on an individual's own performance. RESULTS: Overall, 62.5% of surgery (95/152) and 59.5% of non-surgery residents (194/326) completed the survey. Surgery residents reported working longer hours per week (83.0 versus 62.5 hours; P < 0.01), and scored higher on the ESS (12.8 versus 9.2; P < 0.01) compared with other residents. Surgery residents scored significantly lower than others on the SDI scale (45.2 versus 51.5, P < 0.01), indicating less perceived impact of sleep deprivation on performance. CONCLUSIONS: These results are consistent with the presence of an underlying culture within surgery in which individuals may be less willing to accept a natural limitation of individual performance. Whether these findings represent an actual resilience to sleep deprivation among surgery residents or a misperception within this group remains to be determined.

Issues for small businesses with waste management.

Participation by small and medium enterprise (SME) in corporate social responsibility issues has been found to be lacking. This is a critical issue, as individually SMEs may have little impact on the environment but their collective footprint is significant. The management style and ethical stance of the owner-manager affects business decision making and therefore has a direct impact on the environmental actions of the business. Although adoption of environmental practices to create competitive advantage has been advocated, many businesses see implementation as a cost which cannot be transferred to their customers. After a brief review of pertinent literature this paper reports on an exploratory investigation into the issue. Results show that whereas owner-managers of small enterprises express concern regarding the environment, this does not then translate into better waste management practices.