Strategic response to COVID-19 in Ethiopia

COVID-19, the novel coronavirus, has posed a major threat to low- and middle-income countries (LMICs) due to inadequate health infrastructure and human resources. Ethiopia, a low-income country with the second largest population in Africa, has coordinated a strategic response, leveraging existing infrastructure and health systems and mobilizing public health professionals and specialist expert physicians for a multifaceted, unified government approach and adaptive response. Resource limitations, particularly in critical care, have still posed challenges, but the public health and clinical interventions thus far have prevented the catastrophic toll that many predicted. As the pandemic continues, Ethiopia expects to use a triple care model integrated at all levels, consisting of COVID-19 care, isolation care for suspected cases, and essential health services, and urges intensified non-pharmaceutical interventions alongside equitable global vaccine distribution as the ultimate answers to pandemic control. This paper draws on existing data, national planning and guidelines, and expertise from health leadership to describe this response in hopes of providing an example of how future large-scale health challenges might be faced in LMICs, using Ethiopia's successes and challenges in facing the pandemic.

Translation of the Amsterdam Preoperative Anxiety and Information Score (APAIS) into the Amharic Version and Its Validation for Evaluation of Preoperative Anxiety

Background

Peri-operative anxiety is a vague, unpleasant feeling, the source of which is often nonspecific and unknown to the individual. It affects all aspects of anesthesia. Although the magnitude and consequences of preoperative anxiety are well documented in the developed world, there are limited studies conducted in Ethiopia. The primary aim of this study is to produce the Amharic version of APAIS and evaluate its validity in assessing the prevalence of preoperative anxiety in surgical patients.

Methods

A cross-cultural adaptation process using a forward/backward translation of the APAIS scale was performed. The Amharic version was then tested in 365 sampled elective adult surgical patients scheduled for surgery at Tikur Anbessa specialized Hospital. The validity of the translated version was also checked by evaluating its psychometric properties of internal validity and acceptability.

Result

The results showed that the reliability of the APAIS-Amharic was high (Cronbach's alpha of 0.87) and the data collected was a good fit (RMSEA of 0.04). In addition, the questionnaire was well-accepted 100% with no missing values for each dimension of the APAIS. The mean APAIS scores for total anxiety and desire for information were 11.6 and 6.0 respectively and 58.9% of the study participants had anxiety and those patients, who had some form of formal education, came from urban areas, had previous anesthesia experience and complications and who had average or high information requirement was more likely to be anxious.

Conclusion

APAIS-Amharic is a reliable and acceptable tool for measuring patients' preoperative anxiety and their need for information. It can be used routinely as a screening instrument at pre-anesthesia clinics to assess patients' level of anxiety.

Airway epithelial stem cell chimerism in cystic fibrosis lung transplant recipients

BACKGROUND

The conducting airway epithelium is repaired by tissue specific stem cells (TSC). In response to mild/moderate injury, each TSC repairs a discrete area of the epithelium. In contrast, severe epithelial injury stimulates TSC migration and expands the stem cell's reparative domain. Lung transplantation (LTx) can cause a moderate/severe airway injury and the remodeled airway contains a chimeric mixture of donor and recipient cells. These studies supported the hypothesis, LTx stimulates TSC migration resulting in epithelial chimerism. We tested this hypothesis in cystic fibrosis (CF) LTx patients.

METHODS

Airway mucosal injury was quantified using bronchoscopic imaging and a novel grading system. Bronchial brushing was used to recover TSC from 10 sites in the recipient and allograft airways. TSC chimerism was quantified by short tandem repeat analysis. TSC self-renewal and differentiation potential were assayed using the clone forming cell frequency and air-liquid-interface methods. Electrophysiology was used to determine if TSC chimerism altered epithelial ion channel activity.

RESULTS

LTx caused a mild to moderate airway mucosal injury. Donor and recipient TSC were identified in 91% of anastomotic sites and 93% of bronchial airways. TSC chimerism did not alter stem cell self-renewal or differentiation potential. The frequency of recipient TSC was proportional to CF Transmembrane Conductance Regulator (CFTR)-dependent ion channel activity and 33% of allograft regions were at risk for abnormal CFTR activity.

CONCLUSIONS

LTx in CF patients stimulates bidirectional TSC migration across the anastomoses. TSC chimerism may alter ion homeostasis and compromise the host defense capability of the allograft airway epithelium.

Building regional anesthesia capacity in limited-resource settings: a pilot study evaluating a 4-week curriculum

Aim: To pilot a 4-week regional anesthesia curriculum for limited-resource settings. Intervention: A baseline needs assessment and knowledge test were deployed. The curriculum included lectures and hands-on teaching, followed by knowledge attainment tests. Results: Scores on the knowledge test improved from a mean of 37.1% (SD 14.7%) to 50.9% (SD 18.6%) (p = 0.017) at 4 weeks and 49% at 24 months. An average of 1.7 extremity blocks per month was performed in 3 months prior to the curriculum, compared with an average of 4.1 per month in 8 months following. Conclusion: This collaborative curriculum appeared to have a positive impact on the knowledge and utilization of regional anesthesia.

Cell Therapy for Cystic Fibrosis Lung Disease: Regenerative Basal Cell Amplification

The human airway epithelium is regenerated by basal cells. Thus, basal cell therapy has the potential to cure cystic fibrosis (CF) lung disease. We previously reported that the human basal cells repopulated the mouse airway epithelium after transplantation, and we estimated that 60 million cells would be needed to treat a human patient. To further develop cell therapy, we compared the proliferation potential of non‐CF and CF tissue‐derived bronchial basal cells. Three methods were used: regenerative cell frequency, burst size, and cell division frequency. Second, we used a serial passage strategy to determine if CF basal cells could be amplified to the estimated therapeutic dose. These studies evaluated that tissue‐derived bronchial basal cells and the basal cells that were recovered by brushing bronchial airways or the nasal respiratory epithelium. Finally, we used the limiting dilution method to isolate non‐CF and CF basal cell clones. The proliferation assays and the air‐liquid‐interface differentiation method were used to determine if cell amplification altered the proliferation and/or differentiation potential of clonal isolates. We demonstrate that: (a) non‐CF and CF basal cell proliferation is similar, (b) CF basal cells can be amplified to a therapeutic cell dose, and (c) amplified non‐CF and CF basal cell clones differentiate normally. Despite these encouraging findings, we also find that the cell amplification process depletes the regenerative basal cell pool. Analysis of basal cell clones indicates that serial passage selects for long‐lived basal cells and raise the possibility that prospective isolation of these stem‐like cells will improve the efficacy of cell replacement therapy. stem cells translational medicine2019;8:225&235

Genomic profiles and predictive biological networks in oxidant-induced atherogenesis

Atherogenic stimuli trigger complex responses in vascular smooth muscle cells (VSMCs) that culminate in activation/repression of overlapping signal transduction cascades involving oxidative stress. In the case of benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon present in tobacco smoke, the atherogenic response involves interference with redox homeostasis by oxidative intermediates of BaP metabolism. The present studies were conducted to define genomic profiles and predictive gene biological networks associated with the atherogenic response of murine (aortic) VSMCs to BaP. A combined oxidant-antioxidant treatment regimen was used to identify redox-sensitive targets during the early course of the atherogenic response. Gene expression profiles were defined using cDNA microarrays coupled to analysis of variance and several clustering methodologies. A predictor algorithm was then applied to gain insight into critical gene-gene interactions during atherogenesis. Supervised and nonsupervised analyses identified clones highly regulated by BaP, unaffected by antioxidant, and neutralized by combined chemical treatments. Lymphocyte antigen-6 complex, histocompatibility class I component factors, secreted phosphoprotein, and several interferon-inducible proteins were identified as novel redox-regulated targets of BaP. Predictor analysis confirmed these relationships and identified immune-related genes as critical molecular targets of BaP. Redox-dependent patterns of gene deregulation indicate that oxidative stress plays a prominent role during the early stages of BaP-induced atherogenesis.

Lack of effect of gender on retinopathy in the mouse

BACKGROUND

The reported effect of gender on retinopathy of prematurity has been controversial. The goal of this study was to determine the effect of gender on oxygen-induced retinopathy in a mouse model.

METHODS

Oxygen-induced retinopathy was produced in C57BL6 mice by exposure to 75% oxygen from postnatal day (P) 7 for 5 days. Animals were returned to room air on P12 and killed on P17-21. Gender was determined by inspection. Retinopathy was evaluated by a retinopathy scoring system and by quantifcation of extraretinal neovascular nuclei on retinal sections.

RESULTS

Both males and females developed similar degrees of retinopathy. Males had a median total retinopathy score of 9 (25th, 75th quartile: 8, 11) and females had score of 9 (25th, 75th quartile: 7, 10). Retinal subscores of blood vessel growth, blood vessel tufts, extraretinal neovascularzation, haemorrhage and blood vessel tortuosity were similar in both groups. Males and females had a similar number of neovascular nuclei on retinal sections.

CONCLUSIONS

Gender does not alter the development of oxygen-induced retinopathy in the C57BL6 mouse.

Captopril improves retinal neovascularization via endothelin-1

PURPOSE

The purpose of this study was to determine the effect of an angiotensin converting enzyme inhibitor, captopril, on oxygen-induced retinopathy (OIR) in the mouse. Endothelin-1 (ET-1) expression is assessed in a mouse model of OIR.

METHODS

OIR was produced in C57BL6 mice. Captopril (0.5mg/kg/d SC) was given from P7 (post natal day 7) for 5 days. Retinopathy was assessed by a retinal scoring system and by quantification of extra retinal neovascular nuclei on retinal sections at P17 to P20. The expression of ET-1 was determined using a reverse transcriptase polymerase chain reaction.

RESULTS

Pups treated with captopril during hyperoxia had a lower median retinopathy score of 4.5 (25th, 75th quartile: 3, 6.4) compared with animals exposed to hyperoxia alone with median score 9.5 (25th, 75th quartile: 7.1, 10.4; P < 0.001). The pups treated with captopril during hyperoxia had significant reduction in number of nuclei extending beyond the inner limiting membrane (15.8 +/- 16.7, mean +/- SD) when compared with the animals exposed to hyperoxia only (50.4 +/- 28.0; P < 0.01). ET-1 expression in the retina increased 4.1-fold from P7 to P12 and a 1.9-fold increase from P12 to P17. Overall, there was an 8-fold increase in ET-1 expression from P7 to P17. Hyperoxia increased ET-1 expression by 2.1-fold at P12 over room air-reared animals. At P17, there was a 2.9-fold increase in retinal ET-1 expression when compared with room air. At P17, there was a 6.2-fold suppression in ET-1 expression in captopril-treated animals when compared with the oxygen only-treated animals.

CONCLUSIONS

Captopril reduces retinal neovascularization in a mouse model of oxygen-induced retinopathy. ET-1 expression is increased from P7 to P17, altered by hyperoxic exposure and relative hypoxic recovery and modulated by captopril in a mouse model of OIR.

Dexamethasone alters TNF-alpha expression in retinopathy

TNF-alpha has been found in the retina. Hyperoxia and hypoxia regulate TNF-alpha expression. TNF-alpha is an important factor in inflammation and angiogenesis. Dexamethasone inhibits TNF-alpha production. Changes in TNF-alpha expression in the retina may play an important role in the development of oxygen-induced retinopathy. Oxygen-induced retinopathy was produced in C57BL6 mice by exposure to 75% oxygen at Postnatal Day 7 (P7) for 5 days and the mice recovered in room air until Day 17 (P17). Dexamethasone was administered at 0.5 mg/kg/day once daily subcutaneously during the 5 days of oxygen exposure. TNF-alpha expression was evaluated at Day 7 prior to oxygen exposure, at Day 12 (P12) immediately upon removal from oxygen, and at Day 17, the time of maximal vasoproliferation by RT-PCR. TNF-alpha is developmentally regulated in the retinae of C57BL6 mice. From P7 to P12, there is a 3-fold increase in TNF-alpha expression and from P7 to P17 there is a 2.7-fold increase. There was 2.7-fold suppression in expression immediately following oxygen exposure at P12. The expression was dramatically increased at P17, the time of maximal vasoproliferation. Dexamethasone inhibited the expression of TNF-alpha at P17 by 6.4-fold. At this dose, it also suppressed the baseline TNF-alpha expression in the mouse model. In summary, TNF-alpha is altered in the development of oxygen-induced retinopathy in the mouse. It increased markedly during the vasoproliferative phase and was suppressed by dexamethasone. Modulation of TNF-alpha expression may provide a potential site of action for future therapeutic targets.

Dexamethasone and critical effect of timing on retinopathy

PURPOSE

Administration of corticosteroids soon after birth has been reported to have deleterious, protective, and no effect on retinopathy of prematurity. Conflicting results may be due to timing of corticosteroid administration. The goal of this study was to determine effects of pretreatment and late dexamethasone on retinopathy in a mouse model.

METHODS

The C57BL6 mouse model of oxygen-induced retinopathy (by placing animals in 75% oxygen from postnatal days 7 through 12) was used to create retinal neovascularization. Dexamethasone at 0.5 mg/kg per day was administered from day 1 through day 5 in the pretreatment group. The late-treatment group received 5 days of dexamethasone at the same dose beginning on day 12. Mice were killed at days 17 through 20, and retinal vasculature was assessed by a retinal scoring system of wholemount preparation after high-molecular-weight fluorescein-labeled dextran perfusion. In addition, retinal neovascularization was assessed by quantification of extraretinal neovascular nuclei in retinal sections. Statistical significance was defined as P: < 0.05 and was determined by the Kruskal-Wallis test, Mann-Whitney test, and Student's t-test.

RESULTS

Oxygen-exposed animals that received treatment with dexamethasone before oxygen exposure had an improvement in retinopathy, with a median score of 6 (5,7; 25th,75th quartiles) compared with 10 (8,11) in the untreated oxygen-exposed (P: < 0.05). The group treated late (after oxygen exposure) with dexamethasone had a median score of 10 (9,11). Pretreatment reduced extraretinal vascularization, when assessed by quantification of neovascular nuclei, to a mean +/- SEM of 19 +/- 9, significantly less than in the untreated oxygen-exposed group (55 +/- 12; P: < 0.05). No difference was observed in the late-treatment group when compared with the untreated oxygen-exposed group. Significant growth retardation, indicated by body weight, was observed in the pretreatment (P: < 0.01) and late-treatment (P: < 0. 05) groups when compared with the control group.

CONCLUSIONS

Timing of dexamethasone administration was critical to the inhibition of development of retinopathy in the mouse model. Degree of growth retardation, measured by body weight, also appeared to be time dependent. These data may explain the different results of clinical observations with respect to corticosteroid treatment, timing, and development of retinopathy.