A Computational Study of Dynamic Obstruction in Type B Aortic Dissection.

A serious complication in aortic dissection is dynamic obstruction of the true lumen (TL). Dynamic obstruction results in malperfusion, a blockage of blood flow to a vital organ. Clinical data reveal that increases in central blood pressure promote dynamic obstruction. However, the mechanisms by which high pressures result in TL collapse are underexplored and poorly understood. Here, we developed a computational model to investigate biomechanical and hemodynamical factors involved in Dynamic obstruction. We hypothesize that relatively small pressure gradient between TL and false lumen (FL) are sufficient to displace the flap and induce obstruction. An idealized fluid-structure interaction model of type B aortic dissection was created. Simulations were performed under mean cardiac output while inducing dynamic changes in blood pressure by altering FL outflow resistance. As FL resistance increased, central aortic pressure increased from 95.7 to 115.3 mmHg. Concurrent with blood pressure increase, flap motion was observed, resulting in TL collapse, consistent with clinical findings. The maximum pressure gradient between TL and FL over the course of the dynamic obstruction was 4.5 mmHg, consistent with our hypothesis. Furthermore, the final stage of dynamic obstruction was very sudden in nature, occurring over a short time (<1 s) in our simulation, consistent with the clinical understanding of this dramatic event. Simulations also revealed sudden drops in flow and pressure in the TL in response to the flap motion, consistent with first stages of malperfusion. To our knowledge, this study represents the first computational analysis of potential mechanisms driving dynamic obstruction in aortic dissection.

The GI Simulated Clinic in the Era of COVID-19: a Comparison of Virtual to In-Person Delivery.

The COVID-19 pandemic has significantly impacted medical education; thus, there is a need to better understand the effectiveness of virtual learning compared to in-person learning. This is a single-center, cross-sectional study of first-year medical students who attended a gastroenterology simulated clinic activity in person in 2018 and 2019 or virtually in 2020. Participants were surveyed on the activity's relevance and effectiveness. Students' assessment of the virtual clinic's effectiveness and relevance was not significantly different from the in-person version of the activity. In addition, most students rated the virtual clinic as effective for learning about telemedicine.

Clostridium difficile infection and risk of Parkinson's disease: a Swedish population-based cohort study.

BACKGROUND AND PURPOSE: Gastrointestinal inflammation has been implicated in Parkinson's disease (PD). The aim of this study was to examine whether individuals with a history of Clostridium difficile infection (CDI) are at elevated risk of PD. METHODS: We performed a population-based cohort study using Swedish national register data. Adults aged ≥35 years were identified from the Swedish Population and Housing Census 1990 and followed during the period 1997-2013. Diagnoses of CDI and PD were extracted from the National Patient Register. Associations of CDI history with PD risk were estimated using Cox proportional hazards regression. We also explored whether the association differed by the source of CDI diagnosis (inpatient vs. outpatient), presence of recurrent infections, and pre-infection use of antibiotics. RESULTS: Amongst the study population (N = 4 670 423), 34 868 (0.75%) had a history of CDI. A total of 165 and 47 035 incident PD cases were identified from individuals with and without CDI history, respectively. Across the entire follow-up, a 16% elevation of PD risk was observed among the CDI group [hazard ratio 1.16, 95% confidence interval (CI)1.00-1.36], which was mainly driven by increased PD risk within the first 2 years after CDI diagnosis (hazard ratio 1.38, 95% CI 1.12-1.69). In longer follow-up, CDI was not associated with subsequent PD occurrence. This temporal pattern of CDI-PD associations was generally observed across all CDI subgroups. CONCLUSIONS: Clostridium difficile may be associated with an increased short-term PD risk, but this might be explained by reverse causation and/or surveillance bias. Our results do not imply that CDI history affects long-term PD risk.

An International Working Definition for Quality of Oral Healthcare.

To assess and improve the quality of oral healthcare, we must first agree on what constitutes good care. Currently there is no internationally accepted definition for quality of oral healthcare. Therefore, the purpose of the study was to establish a working definition for quality of oral healthcare that would help to advance further improvements in the field of quality improvement in oral healthcare. The development of the working definition included a 3-step approach: 1) literature screening; 2) expert-based compilation of an initial list of topics, leaning on the National Academy of Medicine framework for quality of care; and 3) a World Café with voting, which took place during the annual general meeting of the International Association for Dental Research in 2018. Following this approach, the collective intelligence of involved participants yielded a comprehensive list of items, prioritized by relevance. The resulting working definition comprises 7 domains­patient safety, effectiveness, efficiency, patient-centeredness, equitability, timeliness, access to care­and 30 items, which together characterize quality of oral healthcare. This aspirational working definition provides the potential to facilitate further conversations and activities aiming at quality improvement in oral healthcare. KNOWLEDGE TRANSFER STATEMENT: This special communication describes the development of a working definition for quality of oral healthcare. The findings of this study are intended to raise awareness of the relevance of quality improvement initiatives in oral healthcare. The working definition described here has the potential to facilitate further conversations and activities aiming at quality improvement in oral healthcare.

Physical exercise and non-insulin glucose-lowering therapies in the management of Type 2 diabetes mellitus: a clinical review.

In the UK the National Institute of Health and Care Excellence (NICE) advocates intensive lifestyle programmes that attain the levels of daily physical activity set out by the Chief Medical Officer as a first-line strategy for improving the health of people at risk of developing diabetes or reducing the risk of development of Type 2 diabetes. For people with Type 2 diabetes, lifestyle measures complement pharmacological treatments that include both oral and injectable therapies. In line with this, NICE guidelines also support intensification of efforts to improve patient lifestyle along with these glucose-lowering therapies. There is a paucity of evidence, however, in the available published literature examining the association between glucose-lowering therapies and exercise metabolism. In the present review we explore the current knowledge with regard to the potential interactions of oral and non-insulin injectable therapies with physical activity in people at risk of, or who have, Type 2 diabetes, and present evidence that may inform healthcare professionals of the need to monitor patients more closely in their adaptation to both pharmacological therapy and physical activity.

A new definition for oral health developed by the FDI World Dental Federation opens the door to a universal definition of oral health.

This article first published as an editorial in the Journal of the American Dental Association presents the FDI World Dental Federation's universal definition of oral health. This new definition was approved in September 2016 and developed as as part of the FDI's advocacy and strategic plan - Vision 2020.

Oral health needs assessment world-wide in relation to HIV. Themes: Oral health needs and inequalities, oral health promotion, co-ordinating research and enhancing dissemination in relation to HIV- a workshop report.

OBJECTIVES: Review the meaning of 'health need', consider oral health inequalities and oral health promotion among people with HIV and outline methods to enhance coordination, standardization and dissemination of research efforts. METHODS: This workshop involved a brief introduction of each topic by an invited speaker followed by participant discussion. Participants were dentists and dental students attending the 7th World Workshop on Oral Health & Disease in AIDS RESULTS: A health need was regarded as a population's ability to benefit from care. Oral health inequalities called for both downstream and upstream health promotion. A community health programme to reach people with HIV infection in the community was described. Despite deploying community health workers to reduce costs, the programme required additional resources for comprehensive implementation. The Indian National AIDS Control Program exemplified coordinated efforts. Knowledge transfer can be achieved via educational, linkage and exchange and organizational interventions. Stakeholder engagement in a combination of all three types of intervention is the most effective. CONCLUSIONS: The discussion centred on the difficulties of Indian dentists who felt they did not receive sufficient revenue to treat patients with HIV. An opposing view approach treated all patients using universal standards of infection control. Dental regulatory bodies, professional organizations and governments may need to demonstrate leadership and advocacy for the oral health of people with HIV infection.

Histone deacetylase inhibition protects hearing against acute ototoxicity by activating the Nf-κB pathway.

Auditory hair cells have repeatedly been shown to be susceptible to ototoxicity from a multitude of drugs including aminoglycoside antibiotics. Here, we found that systemic HDAC inhibition using suberoylanilide hydroxamic acid (SAHA) on adult mice offers almost complete protection against hair cell loss and hearing threshold shifts from acute ototoxic insult from kanamycin potentiated with furosemide. We also found that the apparent lack of hair cell loss was completely independent of spontaneous or facilitated (ectopic Atoh1 induction) hair cell regeneration. Rather, SAHA treatment correlated with RelA acetylation (K310) and subsequent activation of the Nf-κB pro-survival pathway leading to expression of pro-survival genes such as Cflar (cFLIP) and Bcl2l1 (Bcl-xL). In addition, we also detected increased expression of pro-survival genes Cdkn1a (p21) and Hspa1a (Hsp70), and decreased expression of the pro-apoptosis gene Bcl2l11 (Bim). These data combined provide evidence that class I HDACs control the transcriptional activation of pro-survival pathways in response to ototoxic insult by regulating the acetylation status of transcription factors found at the crossroads of cell death and survival in the mammalian inner ear.

Reducing Inequalities in Oral Health in the Africa and Middle East Region.

Dentistry is facing many serious challenges and threats. Addressing them will require major changes in strategy. This work outlines the extent of dental disease in the Africa and Middle East Region (AMER) and suggests strategies to reduce inequalities in oral health. The main oral health challenges in the AMER relate to controlling the relentless increase in caries with age. A very conservative estimate of population caries levels suggests that a 5-fold increase in dental personnel would be required just to treat current levels of caries. Hence, we argue that current approaches to control caries in the AMER are both ineffective and unaffordable, and a new model to promote oral health is needed. Unless determinants of noncommunicable diseases are addressed and access to evidence-based minimal intervention dental care is improved, the burden of dental disease will persist. The new oral health promotion model calls for an integrated intersectoral common risk factor approach, namely, "oral health in all policies" (OHiAP). An OHiAP framework will initiate high-level policy initiatives and intersectoral partnerships. Oral health professionals have an important advocacy role in securing the fundamental changes in health strategy needed to control the growing, unjust, and unaffordable burden of oral disease.

Characterizing the immunological effects of oral healthcare ingredients using an in vitro reconstructed human epithelial model.

Oral healthcare products are well tolerated and while adverse occurrences are rare there is still a need to explore the interaction between these products and the oral mucosa. This study assessed the effects of oral healthcare ingredients: sodium lauryl sulphate (SLS), a detergent; cinnamic aldehyde (CA), a flavouring agent; and cetylpyridinium chloride (CPC), an antiseptic, using a reconstructed human oral mucosal model (OMM). Differential release of inflammatory cytokines IL-1α, IL-8 and cytotoxicity was compared with other known irritants and sensitizers to identify a signature response profile that could be associated with oral mucosal irritation. Response profiles differed with irritants being more cytotoxic. CA and control sensitizers nickel sulphate (NiSO4) and 1-chloro-2,4-dinitrochlorobenzene (DNCB) released lower levels of IL-1α than CPC and control irritant benzalkonium chloride (BC), whereas the opposite was observed for IL-8. Significant levels of IL-8 and IL-1α were released with 5-15 mg/ml (0.5-1.5% w/v) SLS. Quantitative PCR indicated that cytokine release at lower SLS concentrations is not entirely due to cell necrosis but in part due to de novo synthesis. These findings suggest that the OMM can be used to predict oral irritation thus making it a potentially valuable model for screening new oral healthcare ingredients prior to clinical release.

The role of the dental team in promoting health equity.

A recent important report endorsed by several prestigious and influential medical and dental organisations has outlined what health professions can do to reduce health inequalities. Despite overall improvements in oral health in recent decades, there are unacceptable inequalities in oral diseases. Urgent action is needed to reduce these unfair and unjust oral health inequalities that exist across society. Primary care dental teams are in an important position to become actively engaged in promoting oral health equity, both for their own patients and the wider community. This paper highlights practical ways that dental teams can become involved in action to reduce oral health inequalities.