Corneal Neurotization for Neurotrophic Keratopathy: Clinical Outcomes and In Vivo Confocal Microscopic and Histopathological Findings

Purpose: To describe the long-term outcomes and in vivo confocal microscopic (IVCM) and histopathological findings after corneal neurotization surgery. / Methods: We included 2 patients who underwent corneal neurotization surgery for severe unilateral neurotrophic keratopathy secondary to cerebellopontine angle meningioma. Corneal sensation was measured using the Cochet–Bonnet esthesiometer (CBE) (0–60 mm). IVCM was performed using the Heidelberg HRT3 Rostock Corneal Module. Histopathological examination was performed on the excised corneoscleral disc of patient 2. / Results: In patient 1, corneal sensation improved from 0 mm preoperatively to 60 mm in all 4 quadrants by 2 years postoperatively and was maintained at 5 years postoperatively with identifiable subbasal and stromal corneal nerves on IVCM. In patient 2, corneal sensation improved from 0 mm preoperatively to 10 mm in 3 quadrants (9 months postoperatively) but returned to 0 mm in all quadrants by 2 years postoperatively. IVCM failed to identify any subbasal and stromal corneal nerves. At 5 years postoperatively, evisceration was performed to ameliorate uncontrolled and persistent ocular pain and poor cosmesis. Histopathological examination of the excised corneoscleral disc confirmed the presence of normal-sized, central corneal stromal nerve fascicles but without direct continuity with the transplanted perilimbal nerve bundles. / Conclusions: Our study elucidates the mechanism of corneal neurotization surgery at a cellular level. Although only 1 patient achieved long-term improvement in corneal sensation postoperatively, the findings on IVCM and histopathological examination suggest that partial regeneration/maintenance of corneal nerves after corneal neurotization surgery is likely attributed to the paracrine neurotrophic support, instead of direct sprouting, from the perilimbal transplanted nerve fascicles

Multiple receptor tyrosine kinases are expressed in adult rat retinal ganglion cells as revealed by single-cell degenerate primer polymerase chain reaction

BACKGROUND: To achieve a better understanding of the repertoire of receptor tyrosine kinases (RTKs) in adult retinal ganglion cells (RGCs) we performed polymerase chain reaction (PCR), using degenerate primers directed towards conserved sequences in the tyrosine kinase domain, on cDNA from isolated single RGCs univocally identified by retrograde tracing from the superior colliculi.RESULTS: All the PCR-amplified fragments of the expected sizes were sequenced, and 25% of them contained a tyrosine kinase domain. These were: Axl, Csf-1R, Eph A4, Pdgfrbeta, Ptk7, Ret, Ros, Sky, TrkB, TrkC, Vegfr-2, and Vegfr-3. Non-RTK sequences were Jak1 and 2. Retinal expression of Axl, Csf-1R, Pdgfrbeta, Ret, Sky, TrkB, TrkC, Vegfr-2, and Vegfr-3, as well as Jak1 and 2, was confirmed by PCR on total retina cDNA. Immunodetection of Csf-1R, Pdgfralpha/beta, Ret, Sky, TrkB, and Vegfr-2 on retrogradely traced retinas demonstrated that they were expressed by RGCs. Co-localization of Vegfr-2 and Csf-1R, of Vegfr-2 and TrkB, and of Csf-1R and Ret in retrogradely labelled RGCs was shown. The effect of optic nerve transection on the mRNA level of Pdgfrbeta, Csf-1R, Vegfr-2, Sky, and Axl, and of the Axl ligands Gas6 and ProteinS, was analysed. These analyses show transection-induced changes in Axl and ProteinS mRNA levels.CONCLUSIONS: The repertoire of RTKs expressed by RGCs is more extensive than previously anticipated. Several of the receptors found in this study, including Pdgfrbeta, Csf-1R, Vegfr-2, Sky, and Axl, and their ligands, have not previously been primarily associated with retinal ganglion cells

Knowledge, Attitude, Practices, and Vaccine Hesitancy Among the Latinx Community in Southern California Early in the COVID-19 Pandemic: Cross-sectional Survey.

BackgroundThe Latinx population in the United States has experienced high rates of infection, hospitalization, and death since the beginning of the COVID-19 pandemic. There is little data on the knowledge, attitude, and practices (KAP) specifically in Latinx communities in the United States.ObjectiveWe aimed to assess COVID-19 KAP and vaccine hesitancy among a Latinx cohort in the early stages of the COVID-19 pandemic (from July 2020 to October 2020), at a unique time when a vaccine was not available.MethodsParticipants aged ≥18 years were recruited at a primary care clinic in Southern California and asked to self-report sociodemographic characteristics, KAP, and vaccine hesitancy. A subset of the participants answered the vaccine hesitancy assessment as it was added after the start of data collection. KAP items were summed to create composite scores, with higher scores reflecting increased COVID-19 knowledge, positive attitudes toward the COVID-19 pandemic, and disease prevention practices. Bivariate and multivariable regression models were fitted to test associations between sociodemographic characteristics and KAP scores. For our analysis, we only included patients who self-identified as Latinx.ResultsOur final data set included 265 participants. The participants had a mean age of 49 (IQR 38.5-59) years, and 72.1% (n=191) were female, 77% (n=204) had at most a high school degree, 34.7% (n=92) had an annual income ConclusionsGood knowledge and preventative practices in the population may have reflected effective public health messaging and the implementation of public health laws during the first wave of the pandemic; however, the overall fear and anxiety may have reflected the negative impact that the pandemic had on vulnerable populations such as the Latinx community. Although our data are a reflection of a previous time in the pandemic, we believe it captures a critical time that can be used to provide unique insights regarding potential avenues to better protect the Latinx communities against future vaccine-resistant COVID-19 strains.International registered report identifier (irrid)RR2-10.2196/25265

A Review of the Configurations, Capabilities, and Cutting-Edge Options for Multistage Solar Stills in Water Desalination

The desalination of saltwater is a viable option to produce freshwater. All the desalination processes are energy-intensive and can be carried out on a large scale. Therefore, producing freshwater using renewable energy sources is the most desirable option considering the current energy crisis and the effect that fossil-fuel-based energy has on our carbon footprint. In this respect, the tray-type still, one of several solar power desalination still varieties, is popular owing to its straightforward design, economic materials of construction, and minimal maintenance requirements, especially in isolated island regions with restricted energy and natural water supplies. The traditional tray-type solar power has a few drawbacks, such as the inability to recover latent heat from condensation, reduced thermal convection, a large heat capacity, and comparatively minimal driving power through evaporation. Therefore, the improvement of heat and mass transfer capabilities in tray-type stills has been the subject of many studies. However, there is a lack of a comprehensive review in the open literature that covers the design and operational details of multistage solar stills. The purpose of this paper is to present a thorough overview of the past research on multistage solar stills, in terms of configurations, capabilities, and cutting-edge options. In comparison to a unit without a salt-blocking formation, the review indicates that a multistage distillation unit may run continuously at high radiation and generate pure water that is around 1.7 times higher than a unit without a salt-blocking formation. The most effective deign is found to be “V”-shaped solar still trays that attach to four-stage stills, since they are less expensive and more economical than the “floor” (Λ-shape) design, which requires two collectors. Additionally, it can be stated that the unit thermal efficiency, solar percentage, and collected solar energy (over the course of a year) increase by 23%, 18%, and 24%, respectively, when the solar collectors are increased by 26% (at the constant inflow velocity of the water)

Diverticular disease of the right colon

<p>Abstract</p> <p>Background</p> <p>The incidence of colonic diverticular disease varies with national origin, cultural background and diet. The frequency of this disease increases with advancing age. Right-sided diverticular disease is uncommon and reported to occur in 1-2% of surgical specimens in European and American series. In contrast the disease is more prevalent and reported in 43-50% of specimens in Asian series. Various lines of evidence suggest this variation may represent hereditary differences. The aim of the study is to report all cases of right sided diverticular disease underwent surgical resection or identified during pathological examination of right hemicoloectomy specimens</p> <p>Methods</p> <p>A retrospective review of all surgical specimens with right sided colonic diverticular disease selected from a larger database of all colonic diverticulosis and diverticulitis surgical specimen reported between January 1993 and December 2010 at the Pathology Department McMaster University Medical Centre Canada. The clinical and pathological features of these cases were reviewed</p> <p>Results</p> <p>The review identified 15 cases of right colon diverticulosis. The clinical diagnoses of these cases were appendicitis, diverticulitis or adenocarcinoma. Eight cases of single congenital perforated diverticuli were identified and seven cases were incidental multiple acquired diverticuli found in specimen resected for right side colonic carcinomas/large adenomas. Laparotomy or laparoscopic assisted haemicolectomies were done for all cases. Pathological examination showed caecal wall thickening with inflammation associated with perforated diverticuli. Histology confirmed true solitary diverticuli that exhibited in two cases thick walled vessels in the submucosa and muscular layer indicating vascular malformation/angiodysplasia. Acquired diverticuli tend to be multiple and are mostly seen in specimens resected for neoplastic right colon diseases.</p> <p>Conclusion</p> <p>Single true diverticular disease of the right colon is usually of congenital type and affects younger age group and may be associated with angiodysplasia in some cases. Multiple false diverticuli are more seen in association with caecal carcinoma or large adenomas. These are usually asymptomatic and are more seen in older patients. However this study dose not reflects the true incidence of the disease in the general population.</p