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Background/Objectives: To determine whether Descemet’s membrane (DM) scrolling occurs primarily along the vertical or horizontal axis and establish whether oval trephination along the axis of least scrolling can reduce the grade of the scroll. Subjects/Methods:The longest limbus-to-limbus axis on 28 sclero-corneal discs was taken as the horizontal axis. The horizontal (n=7) or (right angles to it) vertical (n=6) axis was marked on the DM before peeling it off. The direction and grade of scrolling was observed. Narrow strips (3-4mm wide) were then cut along the two axes (n=4 each) and the scrolling pattern observed. Ellipses (7x9mm) of DM were punched along the two axes (n=6 each) and the scrolls graded. Immunofluorescent staining for elastin, on horizontal and vertical tissue sections from 3 DM samples was performed. The intensity and thickness of elastin staining were measured. Results: 24 (85.72%) DM samples showed scrolling along the horizontal axis, none along the vertical axis, and 4 (14.28%) showed a spiral scroll, regardless of which axis was marked (grade 3.7 and 3.6). Vertically oval discs showed significantly reduced scrolling (grade 1.2) compared to horizontally oval discs (grade 3.5). Narrow strips of DM showed a similar scrolling pattern. Immunohistology showed no difference in any of the parameters examined, along the two axes or from center to periphery. Conclusion: DM scrolls primarily along the horizontal axis. Vertically oval DM samples show minimal scrolling, which can be an advantage in DMEK. The differential scrolling is not determined by the distribution of elastin.

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Traumatic brain injury (TBI) is increasingly recognised as being responsible for a substantial proportion of the global burden of disease. Neurosurgical interventions are an important aspect of care for patients with TBI, but there is little epidemiological data available on this patient population. We aimed to characterise differences in casemix, management, and mortality of patients receiving emergency neurosurgery for TBI across different levels of human development. Methods: We did a prospective observational cohort study of consecutive patients with TBI undergoing emergency neurosurgery, in a convenience sample of hospitals identified by open invitation, through international and regional scientific societies and meetings, individual contacts, and social media. Patients receiving emergency neurosurgery for TBI in each hospital's 30-day study period were all eligible for inclusion, with the exception of patients undergoing insertion of an intracranial pressure monitor only, ventriculostomy placement only, or a procedure for drainage of a chronic subdural haematoma. The primary outcome was mortality at 14 days postoperatively (or last point of observation if the patient was discharged before this time point). Countries were stratified according to their Human Development Index (HDI)—a composite of life expectancy, education, and income measures—into very high HDI, high HDI, medium HDI, and low HDI tiers. Mixed effects logistic regression was used to examine the effect of HDI on mortality while accounting for and quantifying between-hospital and between-country variation. Findings: Our study included 1635 records from 159 hospitals in 57 countries, collected between Nov 1, 2018, and Jan 31, 2020. 328 (20%) records were from countries in the very high HDI tier, 539 (33%) from countries in the high HDI tier, 614 (38%) from countries in the medium HDI tier, and 154 (9%) from countries in the low HDI tier. The median age was 35 years (IQR 24–51), with the oldest patients in the very high HDI tier (median 54 years, IQR 34–69) and the youngest in the low HDI tier (median 28 years, IQR 20–38). The most common procedures were elevation of a depressed skull fracture in the low HDI tier (69 [45%]), evacuation of a supratentorial extradural haematoma in the medium HDI tier (189 [31%]) and high HDI tier (173 [32%]), and evacuation of a supratentorial acute subdural haematoma in the very high HDI tier (155 [47%]). Median time from injury to surgery was 13 h (IQR 6–32). Overall mortality was 18% (299 of 1635). After adjustment for casemix, the odds of mortality were greater in the medium HDI tier (odds ratio [OR] 2·84, 95% CI 1·55–5·2) and high HDI tier (2·26, 1·23–4·15), but not the low HDI tier (1·66, 0·61–4·46), relative to the very high HDI tier. There was significant between-hospital variation in mortality (median OR 2·04, 95% CI 1·17–2·49). Interpretation: Patients receiving emergency neurosurgery for TBI differed considerably in their admission characteristics and management across human development settings. Level of human development was associated with mortality. Substantial opportunities to improve care globally were identified, including reducing delays to surgery. Between-hospital variation in mortality suggests changes at an institutional level could influence outcome and comparative effectiveness research could identify best practices. Funding: National Institute for Health Research Global Health Research Group.

The coronavirus pandemic has had significant effects on individuals, healthcare systems and governments. In the UK, whilst routine dentistry was suspended, an urgent dental care system was required to support urgent patient need. Using an adapted model of Donabedians’ framework, a critical evaluation of the services developed and implemented is provided and the various innovative approaches involved in this work are discussed. The three domains of the framework are structure, process and outcome. Structure: We present the principles for selecting and initiating hubs, the integration with secondary care services and the supply of personal protective equipment. Process: The main elements are communication, the development of referral processes to manage complex cases and data collection. Outcome: Through work with local dental stakeholders, 23 clusters and 36 hubs were set up covering a large geographical area. The integrated network of hubs and clusters has strengthened collaboration between providers and policy makers. Various leadership approaches facilitated the readiness for the transition to recovery. The new local collaborative structures could be used to support local programmes such as flexible commissioning, peer-led learning and integration with primary care networks.

Background The etiology of facial nerve palsy is diverse and includes herpes zoster virus, Guillain-Barre syndrome (GBS), otitis media, Lyme disease, sarcoidosis, human immunodeficiency virus, etc. The lower motor neuron type facial nerve palsy is usually caused by an ipsilateral facial nerve lesion; however, it may be caused by a central lesion of the facial nerve nucleus and tract in the pons. Facial diplegia is an extremely rare condition that occurs in approximately 0.3% to 2.0% of all facial palsies. Electrodiagnostic studies including direct facial nerve conduction, facial electromyography (EMG), and blink reflex studies are useful for the prognosis and lesion localization in facial nerve palsy. Methodology This retrospective, observational study was conducted at the Neurophysiology Unit, Hamad General Hospital, Doha, Qatar. This study included 11 patients with bilateral facial weakness who visited for electrodiagnostic studies in the neurophysiology laboratory. Results In total, eight (72.7%) patients had facial diplegia, eight (72.7%) had hypo/areflexia, seven (63.6%) had facial numbness, and five (45.5%) had cerebrospinal fluid albuminocytological dissociation. The most frequent cause of facial diplegia in this study was GBS (81.9%). Direct facial nerve conduction stimulation showed that nine (81.8%) patients had bilateral facial nerve low compound muscle action potential amplitudes. The bilateral blink reflex study showed that eight (88.8%) patients had absent bilateral evoked responses. Finally, the EMG study showed that five (55.5%) patients had active denervation in bilateral sample facial muscles. Conclusions Bilateral facial nerve palsy is an extremely rare condition with a varied etiology. Electrodiagnostic studies are useful in detecting the underlying pathophysiologic processes, prognosis, and central or peripheral lesion localization in patients with facial diplegia.

There is growing evidence that the pathogenesis of retinal diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD) have a significant chronic inflammatory component. A vital part of the inflammatory cascade is through the activation of pattern recognition receptors (PRR) such as toll-like receptors (TLR). Here, we reviewed the past and current literature to ascertain the cumulative knowledge regarding the effect of TLRs on the development and progression of retinal diseases. There is burgeoning research demonstrating the relationship between TLRs and risk of developing retinal diseases, utilising a range of relevant disease models and a few large clinical investigations. The literature confirms that TLRs are involved in the development and progression of retinal diseases such as DR, AMD, and ischaemic retinopathy. Genetic polymorphisms in TLRs appear to contribute to the risk of developing AMD and DR. However, there are some inconsistencies in the published reports which require further elucidation. The evidence regarding TLR associations in retinal dystrophies including retinitis pigmentosa is limited. Based on the current evidence relating to the role of TLRs, combining anti-VEGF therapies with TLR inhibition may provide a longer-lasting treatment in some retinal vascular diseases.

Introduction Worldwide, there are more than 424 million confirmed cases of COVID-19. Most of the hospitalized critical COVID-19 patients manifested neurological signs and symptoms and higher mortality. The majority of COVID-19 fatalities occurred mostly in patients with advanced age and underlying medical comorbidities. This is the first local retrospective study in Qatar, which reported neurologic manifestations (48.5%) of hospitalized COVID-19 patients. The primary objective of this study is to evaluate acute neurological manifestations in COVID-19 hospitalized patients in the country. Methods This is a retrospective, observational study of 413 hospitalized COVID-19 patients. They were admitted to three different COVID-19 designated hospitals (Hazm Mebaireek, Ras Laffan, and Cuban tertiary care Hospitals) under the Hamad Medical Corporation, Qatar from 1st January 2020, to 31 January 2021. We evaluated electronic medical records of these patients and data were collected while their neurological manifestations were confirmed by two trained neurologists. These neurologic manifestations were categorized into three major groups: central nervous system (CNS), peripheral nervous system (PNS), and neuromuscular system. Results Of 413 patients, 94% (389) were male and 6% (24) were female; the mean age was 52 years. Among all different nationalities of COVID-19 patients, 20.3% (84) were Indian, 12.5% (52) were Bangladeshi, 10.1% (42) were Qatari and 9.2% (38) were Nepali. The most common symptoms at the onset of COVID-19 illness were as follows: 77.5% (321) had a fever, 67.4% (279) experienced cough, 58.7% (243) experienced shortness of breath and 26.1% (108) developed a sore throat. Overall 48.5% (201) patients developed different neurologic manifestations. The most common neurologic symptoms were myalgia (28%; 116), headache (10.4%; 43), dizziness (5.8%; 24) and hemiparesis due to strokes (5.3%; 22). In this study, the most common risk factors were hypertension (47.6%), diabetes (46.9%), obesity (21%), chronic kidney disease (10%), ischemic heart disease (9.7%), and smoking (6.8%). About 45.2% (187) patients were admitted to MICU and 8.5% (35) died due to COVID-19 complications. Significant other extrapulmonary multiorgan system involvement were skeletal muscle injury (39.4%), kidney injury (36.7%), liver injury (27.5%), myocardial injury (23.9%), rhabdomyolysis (15.7%) heart failure (11.4%) and acute pancreatitis (11.1%). Discussion The most common neurologic signs and symptoms were myalgia, headache, dizziness, and strokes, mainly due to large vessel thrombosis, lacunar, and posterior circulation strokes. Conclusions Patients with COVID-19 are at high risk of developing neurological manifestations. The most common COVID-19-related acute neurological manifestations were myalgia, headache, dizziness, and acute ischemic stroke. Prompt recognition, early diagnosis, and appropriate management of these manifestations could potentially lead to better patient outcomes in COVID-19 patients.

The efficient monitoring of the environment is currently gaining a continuous growing interest in view of finding solutions for the global pollution issues and their associated climate change. In this sense, two-dimensional (2D) materials appear as one of highly attractive routes for the development of efficient sensing devices due, in particular, to the interesting blend of their superlative properties. For instance, graphene (Gr) and graphitic carbon nitride g-C3N4 (g-CN) have specifically attracted great attention in several domains of sensing applications owing to their excellent electronic and physical-chemical properties. Despite the high potential they offer in the development and fabrication of high-performance gas-sensing devices, an exhaustive comparison between Gr and g-CN is not well established yet regarding their electronic properties and their sensing performances such as sensitivity and selectivity. Hence, this work aims at providing a state-of-the-art overview of the latest experimental advances in the fabrication, characterization, development, and implementation of these 2D materials in gas-sensing applications. Then, the reported results are compared to our numerical simulations using density functional theory carried out on the interactions of Gr and g-CN with some selected hazardous gases’ molecules such as NO2, CO2, and HF. Our findings conform with the superior performances of the g-CN regarding HF detection, while both g-CN and Gr show comparable detection performances for the remaining considered gases. This allows suggesting an outlook regarding the future use of these 2D materials as high-performance gas sensors.

BackgroundFungal keratitis (FK) is the leading cause of unilateral blindness in the developing world. Antimicrobial peptides (AMPs) have been shown to play an important role on human ocular surface (OS) during bacterial, viral and protozoan infections. In this study, our aim was to profile a spectrum of AMPs in corneal tissue from patients with FK during the active pase of infection and after healing.MethodsOS samples were collected from patients at presentation by impression cytology and scraping. Corneal button specimens were collected from patients undergoing therapeutic penetrating keratoplasty for management of severe FK or healed keratitis. Gene expression of human beta-defensin (HBD)-1, -2, -3 and -9, S100A7, and LL-37 was determined by quantitative real-time PCR.ResultsMessenger RNA expression (mRNA) for all AMPs was shown to be significantly upregulated in FK samples. The levels of HBD-1 and -2 mRNA were found to be elevated in 18/20 FK samples. Whereas mRNA for HBD-3 and S100A7 was upregulated in 11/20 and HBD9 was increased in 15/20 FK samples. LL-37 mRNA showed moderate upregulation in 7/20 FK samples compared with controls. In healed scar samples, mRNA of all AMPs was found to be low and matching the levels in controls.ConclusionAMP expression is a consistent feature of FK, but not all AMPs are equally expressed. HBD-1 and -2 are most consistently expressed and LL-37 the least, suggesting some specificity of AMP expression related to FK. These results will help to identify HBD sequence templates for designing FK-specific peptides to test for therapeutic potential.

This paper considers multiple target localization using a non-coherent bi-static radar with multiple receivers, where the targets are located behind a wall. This paper presents a new clustering algorithm inspired by Newtonian gravity that iteratively groups particles at target locations and eliminates particles at non-target locations. We first propose a histogram based pre-processing algorithm that imposes a grid over the region of interest and defines a particle with measurement-dependent mass for each grid square. We then calculate a Newtonian inspired force on each of the particles and move them in the direction of the force. We repeat the process until there is no further movement. The proposed algorithm works even when some of the measurements are unavailable or missing and when some of the measurements are false measurements. Location accuracy is shown to be in the order of 8 cm.

Retinal diseases are the leading causes of irreversible blindness worldwide. The role of toll-like receptor (TLR) signalling mechanisms (MyD88 and TRIF) in the production of pro-angiogenic growth factors from human microvascular endothelial cells (HMEC-1) under hypoxic stress remains unexplored. HMEC-1 was incubated under normoxic (5% CO2 at 37 °C) and hypoxic (1% O2, 5% CO2, and 94% N2, at 37 °C) conditions for 2, 6, 24, and 48 h, respectively. For TLR pathway analysis, HMEC-1 was pre-treated with pharmacological inhibitors (Pepinh-MyD88 and Pepinh-TRIF) and subjected to normoxia and hypoxia conditions. Gene and protein expressions of vascular endothelial growth factor-A (VEGF-A), fibroblast growth factor (FGF-2), hypoxia inducible factor 1-alpha (HIF1-α) were performed using quantitative polymerase chain reaction (qPCR), ELISA, and Western blot methodologies. Levels of TLR3 and TLR4 were analysed by flow cytometry. Under hypoxia, levels of VEGF-A and FGF-2 were elevated in a time-dependent fashion. Inhibition of MyD88 and TRIF signalling pathways decreased FGF-2 levels but failed to modulate the secretion of VEGF-A from HMEC-1. Blocking a known regulator, endothelin receptor (ETR), also had no effect on VEGF-A secretion from HMEC-1. Overall, this study provides the proof-of-concept to target TLR signalling pathways for the management of blinding retinal diseases.

Purpose To verify the concept of adult acquired flat foot following ACL rupture by Podogram method comparing injured and non injured sides. Material and method From January 2017 to July 2017, Patients who had unilateral and chronic ACL rupture, confirmed clinically and on MRI, formed the material of present study. In all the patients who could stand a Podogram was obtained of foot on a Graph paper including both injured and uninjured sides. On the podograms the area occupied by weight bearing portion of foot was measured. Results Total number of patients studied were 23. Total number of podograms were 46. The mean value of area occupied on podogram on injured and non injured side were 115.26 and 102.36 respectively. The range of difference between the podograms of both limbs (ACL ruptured and normal) was 0.00 cm2–43.75 cm2 calculated p value was 0.0109 which was statistically significant. Conclusion The Podogram data of ACL ruptured limb and uninjured contralateral limb are in support of our hypothesis of Adult Acquired Flat foot in ACL ruptured patients.

© 2019 American Society for Investigative Pathology Single-nucleotide polymorphisms and rare mutations in factor H (FH; official name, CFH) are associated with age-related macular degeneration and atypical hemolytic uremic syndrome, a form of thrombotic microangiopathy. Mice with the FH W1206R mutation (FH R/R ) share features with human atypical hemolytic uremic syndrome. Herein, we report that FH R/R mice exhibited retinal vascular occlusion and ischemia. Retinal fluorescein angiography demonstrated delayed perfusion and vascular leakage in FH R/R mice. Optical coherence tomography imaging of FH R/R mice showed retinal degeneration, edema, and detachment. Histologic analysis of FH R/R mice revealed retinal thinning, vessel occlusion, as well as degeneration of photoreceptors and retinal pigment epithelium. Immunofluorescence showed albumin leakage from blood vessels into the neural retina, and electron microscopy demonstrated vascular endothelial cell irregularity with narrowing of retinal and choroidal vessels. Knockout of C6, a component of the membrane attack complex, prevented the aforementioned retinal phenotype in FH R/R mice, consistent with membrane attack complex–mediated pathogenesis. Pharmacologic blockade of C5 also rescued retinas of FH R/R mice. This FH R/R mouse strain represents a model for retinal vascular occlusive disorders and ischemic retinopathy. The results suggest complement dysregulation can contribute to retinal vascular occlusion and that an anti-C5 antibody might be helpful for C5-mediated thrombotic retinal diseases.

Background: Traumatic Intraventricular hemorrhage is commonly associated with other lesions like intracerebral contusions, subdural hemorrhage and subarachnoid hemorrhage. Isolated post- traumatic intraventricular hemorrhage is uncommon. It is mostly seen in the pediatric population and rarely seen in adults. Aims: To analyze the Demographics, mode of Injuries and outcome in injuries causing isolated post traumatic intraventricular hemorrhage which is a rare entity. Materials and Methods: This is a Retrospective analytic study of six cases, conducted at our Hospital in a span of eight years [2010-2018]. Results: Mean age of presentation is 36 years and all were males. The most common clinical presentation included loss of consciousness followed by vomiting and ENT bleed. Four cases presented with severe head injury and two with mild head injury as per Glasgow coma scale score. Mode of injury was acceleration and deceleration in all the cases. NCCT and CT Angiogram brain were done in all the cases which revealed isolated intraventricular hemorrhage without any vascular or tumoral pathology. All the patients were managed conservatively. Conclusion: The outcome was equivocal (3 patients had a bad outcome and 3 good outcomes) in our study.