DOES THE LOW AND SHORT MEDIAL CUT AFFECT LINGUAL NERVE RECOVERY AFTER SAGITTAL SPLIT OSTEOTOMY?

PURPOSE: To evaluate the recovery of lingual nerve (LN) neurosensory function in patients undergoing sagittal split osteotomy (SSO) with a low and short medial horizontal cut. MATERIALS AND METHODS: This was a prospective study of patients with mandibular deformities undergoing SSO with a low and short medial horizontal cut over a 4-year period. The outcomes of interest were neurosensory recovery of the LN, as assessed objectively using functional sensory recovery (FSR) and subjectively by patient report. RESULTS: The sample included 123 SSOs in 62 subjects with a mean age of 19.3 ± 3.1 years. Thirty-seven (61.7%) subjects were female. Mandibular advancements were performed in 52 SSOs (42.3%); mandibular setbacks were performed in 71 SSOs (57.7%). One subject underwent revision BSSO. FSR was achieved at 122 LNs (99.1%) within 6-weeks post-operatively, with 120 sites (97.5%) having S4 sensation at 6-weeks. Decreased LN sensation was reported at 10 (8.3%) sites at 1-week post-operatively. At 6-weeks post-operatively, 118 sites (97.5%) had reported normal sensation. By 12-weeks post-operatively, all LN sites had S4 sensation and there were no subjective complaints. Revision sagittal split osteotomy was associated with prolonged (≥6 weeks) time to S4 sensation (p = 0.02) and subjective complaint of decreased sensation (p = 0.02). CONCLUSION: LN sensory recovery occurs rapidly following the low and short SSO, with 99% of sites achieving FSR and subjectively normal sensation within 6-weeks of surgery and all patients achieving FSR with S4 sensation by 12-weeks post-operatively. LN sensory recovery may be prolonged in patients undergoing revision SSO.

Community and facility-level barriers to achieving UHC in Kono District, Sierra Leone and Maryland County, Liberia.

Universal Health Coverage (UHC) is achieved when individuals and communities receive the health services they need without suffering financial hardship. However, many countries face barriers to building health systems that enable the availability of affordable, accessible care. The goal of this study was to present a model of local monitoring of barriers and to provide a roadmap for designing interventions that improve access to and use of healthcare delivery systems. We conducted household, individual, and health facility surveys in seven catchment areas in Sierra Leone and Liberia between December 2019 and March 2020. A two-stage cluster sampling method was used to sample households and individuals, and all health facilities were included. We divide access barriers into demand (patient-side care seeking behavior), supply (availability of facilities and services), and their intersection (affordability, spending, and use rates). Among the 2,576 respondents within our 1,051 surveyed households, the propensity to seek care when ill was reported at 90% in Sierra Leone (n = 1,283) and 70% in Liberia (n = 806). We estimated that 31% of households spent greater than 10% of their total expenditure on healthcare in a month, and that 14.5% of households spent greater than 25%. Overall, the general service readiness index mean score for all health centers was around 70%. The greatest hindrance to service readiness was the availability of essential medicines, with facilities reporting an average score of 32% in Sierra Leone and 63% in Liberia. Our evidence suggests that the cost of care is both a barrier to care-seeking and a persisting problem among care-seeking patients. Lack of service availability (essential equipment and medicines), poses a risk to high-quality care. The research team recommends deploying interventions (visit cost subsidies, supply chain improvements) targeted at resolving these issues in order to advance the goal of achieving UHC.

COVID-19 vaccine acceptance in three rural communes in Haiti: A cross-sectional study.

Vaccines are the most effective mechanism for ending the COVID-19 pandemic. However, reluctance to accept vaccines has hindered the efforts of health authorities to combat the virus. In Haiti, as of July 2021, less than 1% of the country's population has been fully vaccinated in part due to vaccine hesitancy. Our goal was to assess Haitian attitudes toward COVID-19 vaccination and investigate the primary reasons for Moderna vaccine hesitancy. We conducted a cross-sectional survey across three rural Haitian communities, in September 2021. The research team used electronic tablets to collect quantitative data from 1,071 respondents, selected randomly across the communities. We report descriptive statistics and identify variables associated with vaccine acceptance using logistic regression built using a backward stepwise approach. Among 1,071 respondents, the overall acceptance rate was 27.0% (n = 285). The most common reason for vaccine hesitancy was "concern about side effects" (n = 484, 67.1%) followed by "concern about contracting COVID-19 from the vaccine" (n = 472, 65.4%). Three-quarters of respondents (n = 817) identified their healthcare workers as their most trustworthy source for information related to the vaccine. In the bivariate analysis, male gender (p = .06) and no history of drinking alcohol (p < .001) were significantly associated with being more likely to take the vaccine. In the final reduced model, only those with a history of drinking alcohol were significantly more likely to take the vaccine (aOR = 1.47 (1.23, 1.87) p < .001). The acceptance rate for the COVID-19 vaccine is low, and public health experts should design and strengthen vaccination campaigns to combat misinformation and public distrust.

SANS Study of PPPO in Mixed Solvents and Impact on Polymer Nanoprecipitation.

We investigate the conformation of poly(2,6-diphenyl-p-phenylene oxide) (PPPO) in good and mixed solvents by small-angle neutron scattering (SANS) across its ternary phase diagram. Dichloromethane was selected as a "good" solvent and heptane as a "poor" solvent whose addition eventually induces demixing and polymer precipitation. Below the overlap concentration c*, the polymer conformation is found to be well described by the polymer-excluded volume model and above by the Ornstein-Zernike expression with a correlation length ξ which depends on the concentration and solvent/nonsolvent ratio. We quantify the decrease in polymer radius of gyration R g , increase in ξ, and effective χ parameter approaching the phase boundary. Upon flash nanoprecipitation, the characteristic particle radius (estimated by scanning electron microscopy, SEM) is found to scale with polymer concentration as well as with nonsolvent content. Significantly, the solution volume per precipitated particle remains nearly constant at all polymer concentrations. Overall, our findings correlate ternary solution structure with the fabrication of polymer nanoparticles by nonsolvent-induced phase separation and precipitation.

Local Effects of Ring Topology Observed in Polymer Conformation and Dynamics by Neutron Scattering-A Review.

The physical properties of polymers depend on a range of both structural and chemical parameters, and in particular, on molecular topology. Apparently simple changes such as joining chains at a point to form stars or simply joining the two ends to form a ring can profoundly alter molecular conformation and dynamics, and hence properties. Cyclic polymers, as they do not have free ends, represent the simplest model system where reptation is completely suppressed. As a consequence, there exists a considerable literature and several reviews focused on high molecular weight cyclics where long range dynamics described by the reptation model comes into play. However, this is only one area of interest. Consideration of the conformation and dynamics of rings and chains, and of their mixtures, over molecular weights ranging from tens of repeat units up to and beyond the onset of entanglements and in both solution and melts has provided a rich literature for theory and simulation. Experimental work, particularly neutron scattering, has been limited by the difficulty of synthesizing well-characterized ring samples, and deuterated analogues. Here in the context of the broader literature we review investigations of local conformation and dynamics of linear and cyclic polymers, concentrating on poly(dimethyl siloxane) (PDMS) and covering a wide range of generally less high molar masses. Experimental data from small angle neutron scattering (SANS) and quasi-elastic neutron scattering (QENS), including Neutron Spin Echo (NSE), are compared to theory and computational predictions.

Correlating effluent concentrations and bench-scale experiments to assess the transformation of endocrine active compounds in wastewater by UV or chlorination disinfection.

Transformation of endocrine active compounds (EACs) by either chlorination (Cl-D) or UV disinfection (UV-D) was studied by field sampling and bench-scale validation studies. Field testing assessed concentration of 13 EACs in effluent at two Chicago area 250 MGD wastewater reclamation plants (WRP) over two years. One WRP uses chlorination/dechlorination while the other employs UV disinfection. Target compounds included bupropion, carbamazepine, citalopram, duloxetine, estradiol, estrone, fluoxetine, nonylphenol, norfluoxetine, norsertraline, paroxetine, sertraline, and venlafaxine. Concentrations of 9/13 target compounds were partially reduced after disinfection (5-65% reduction). None of the target compounds were fully transformed by either chlorination or UV treatment at the WRP scale. In bench-scale experiments each compound was spiked into deionized water or effluent and treated in a process mimicking plant-scale disinfection to validate transformations. Correlation was observed between compounds that were transformed in bench-testing and those that decreased in concentration in post-disinfection WRP effluent (10/13 compounds). A survey of potential reaction products was made. Chlorination of some amine containing compounds produced chloramine by-products that reverted to the initial form after dechlorination. Transformation products produced upon simulated UV disinfection were more diverse. Laboratory UV-induced transformation was generally more effective under stirred conditions, suggesting that indirect photo-induced reactions may predominate over direct photolysis.

Incidence and Management of Clozapine-Induced Myocarditis in a Large Tertiary Hospital.

OBJECTIVE: Clozapine, an antipsychotic reserved for management of treatment-resistant schizophrenia, is associated with severe adverse effects, including myocarditis. This study aims to determine the incidence of clozapine-induced myocarditis at a large tertiary hospital compared to what is reported in the literature. METHODS: Medical records of adult patients admitted to psychiatry units receiving clozapine between January 1, 2010, and July 31, 2016, were retrospectively reviewed. Cases of clozapine-induced myocarditis were defined as having elevated C-reactive protein (CRP) or detectable troponin and at least 1 sign or symptom of myocarditis, in the absence of alternative plausible aetiologies. The primary outcome was incidence of clozapine-induced myocarditis during the study period. Secondary outcomes included rate and description of the management of clozapine-induced myocarditis. RESULTS: In total, 316 patients were screened; 10 patients met the case definition for clozapine-induced myocarditis. The incidence of this adverse drug reaction over the study period was 3.16%. Reduced left ventricular ejection fraction was observed in 60% of cases, and electrocardiography changes were noted in 60% of cases. Clozapine was discontinued in all cases. Rechallenge was performed in 2 patients; recurrent CRP elevation resulted in discontinuation in each case. Medications for management of myocarditis were used in 50% of cases. Although 2 patients required transfer to critical care, the in-hospital mortality rate was 0%. CONCLUSIONS: The incidence of clozapine-induced myocarditis at the study hospital was consistent with the higher range reported in the literature. Further research is necessary to elucidate risk factors, definitive diagnostic criteria, and effective management of clozapine-induced myocarditis.

Production and isolation of axons from sensory neurons for biochemical analysis using porous filters.

Neuronal axons use specific mechanisms to mediate extension, maintain integrity, and induce degeneration. An appropriate balance of these events is required to shape functional neuronal circuits. The protocol described here explains how to use cell culture inserts bearing a porous membrane (filter) to obtain large amounts of pure axonal preparations suitable for examination by conventional biochemical or immunocytochemical techniques. The functionality of these filter inserts will be demonstrated with models of developmental pruning and Wallerian degeneration, using explants of embryonic dorsal root ganglion. Axonal integrity and function is compromised in a wide variety of neurodegenerative pathologies. Indeed, it is now clear that axonal dysfunction appears much earlier in the course of the disease than neuronal soma loss in several neurodegenerative diseases, indicating that axonal-specific processes are primarily targeted in these disorders. By obtaining pure axonal samples for analysis by molecular and biochemical techniques, this technique has the potential to shed new light into mechanisms regulating the physiology and pathophysiology of axons. This in turn will have an impact in our understanding of the processes that drive degenerative diseases of the nervous system.

XIAP regulates caspase activity in degenerating axons.

Our knowledge of the destructive events that regulate axonal degeneration is rudimentary. Here, we examine the role of caspases and their endogenous inhibitor, the X-linked inhibitor of apoptosis protein (XIAP), in axonal degeneration of dorsal root ganglion (DRG) axons. We show that caspase-3, caspase-6, and caspase-9 are present in axons and are cleaved upon nerve growth factor (NGF) withdrawal. We observed that caspase-3 activity is high in NGF-withdrawn axons and that CASP3(-/-) axons are protected from degeneration. XIAP(-/-) DRG sensory neurons degenerate more rapidly and contain more active caspase-3 than their wild-type counterparts, indicating that axonal caspases are normally regulated by XIAP. Importantly, axonal XIAP levels drop sharply after NGF withdrawal; if XIAP levels are maintained by overexpression, axonal caspase-3 activation and axonal degeneration are suppressed. Finally, we show that XIAP(-/-) embryos have stunted dermal innervation. We propose that XIAP-mediated caspase inhibition plays an important role in regulating morphogenic events that shape the nervous system during development.

A simple approach to polymer mixture miscibility.

Polymeric mixtures are important materials, but the control and understanding of mixing behaviour poses problems. The original Flory-Huggins theoretical approach, using a lattice model to compute the statistical thermodynamics, provides the basic understanding of the thermodynamic processes involved but is deficient in describing most real systems, and has little or no predictive capability. We have developed an approach using a lattice integral equation theory, and in this paper we demonstrate that this not only describes well the literature data on polymer mixtures but allows new insights into the behaviour of polymers and their mixtures. The characteristic parameters obtained by fitting the data have been successfully shown to be transferable from one dataset to another, to be able to correctly predict behaviour outside the experimental range of the original data and to allow meaningful comparisons to be made between different polymer mixtures.