COVID-19 vaccination plans in Latin America and the Caribbean: a multi-country comparative analysis of prioritization strategies.

OBJECTIVES: This study aimed to synthesize and compare the prioritization strategies outlined in the national vaccination plans (NVPs) against Coronavirus Disease 2019 (COVID-19) developed by countries in the Latin America and Caribbean (LAC) region. STUDY DESIGN: We conducted a comparative policy analysis based on COVID-19 NVPs. METHODS: We conducted a search strategy in three stages to identify NVPs for COVID-19 across 41 countries/territories in the LAC region. Sources included official governmental repositories, complementary Google searches, and less formal documentation. We extracted key variables and conducted a comparative policy analysis based on the prioritization criteria and specific prioritization groups. RESULTS: The study identified 52 NVPs for COVID-19, corresponding to 27 (65.8 %) out of 41 countries/territories in the LAC region. Official national websites yielded documents for 12 countries. All NVPs included frontline healthcare personnel in the first prioritization phase/stage, whilst some included residents of long-term healthcare facilities, adults aged 60 years or more, and people with disabilities. The decision criteria for prioritization were declared in 14 countries/territories. Ethical considerations declared in five NVPs included human welfare, equality, solidarity, equity, and social justice as values. CONCLUSION: The early stages of vaccination rollout in LAC countries prioritized protection of the healthcare system and epidemiological risk for severe disease. Few countries included ethical considerations in their NVPs, and global inequities in vaccine access and distribution led to varied protections for vulnerable populations across LAC. This analysis highlights the need for improved emergency-response capacity, planning, and enhanced multilateral cooperation in the LAC region for future public health emergencies.

Assessment of chitosan-based adsorbents for glyphosate removal.

Exposure to glyphosate produces various toxic effects, due to this, different methods have been evaluated for its elimination. The objective of this work was to formulate chitosan-based adsorbents and evaluate their efficiency in the removal of glyphosate in vitro. Four films were made by varying the weight ratio of silica/chitosan particles, and four sponges were made by varying the chitosan/chitosan ratio in a reticulated manner. Both adsorbents were characterized based on their porosity, water absorption, glyphosate removal, and reusability. It was found that increasing the porosity in both films and sponges resulted in an increase in the adsorption efficiency of glyphosate. The adsorption process exhibited a better fit in both adsorbents to the pseudo-second-order model. The adsorption of glyphosate to the films fit better with the Langmuir model, demonstrating that the process occurs in the form of a monolayer. In the case of sponges, the adsorption of glyphosate fit better with the Freundlich model, indicating that the process takes place in a multilayer form. Finally, when the reusability was evaluated, the adsorbents showed a loss of effectiveness. However, they still proved to be an efficient alternative for the removal of glyphosate in water, providing a cost-effective and environmentally friendly solution.

Unacceptable persistence of territorial inequalities in avoidable under-five mortality in Colombia between 2000 and 2019: a multilevel approach.

OBJECTIVES: This study aimed at evaluating territorial inequalities in avoidable mortality in children under 5 years of age in Colombia between 2000 and 2019. STUDY DESIGN: This was an ecological study. METHODS: An ecological, longitudinal, multigroup study was conducted using secondary sources. Because of the hierarchical structure of the data, the effect of territorial characteristics on the count of avoidable under-five deaths was estimated using a three-level negative binomial regression model with random intercepts for municipality and fixed intercepts for time and departments. RESULTS: Between 2000 and 2019, there were 216,809 avoidable under-five deaths in Colombia (91.3% of all registered deaths of children under 5 years of age). A total of 1117 municipalities located in 33 departments were analyzed over five 4-year periods. Ecological relationships were found between avoidable under-five mortality and the percentage of adolescent births, female illiteracy, and multidimensional poverty at the municipal level (standardized mortality ratio: 1.43 95% confidence interval: 1.33-1.54 for the group with the highest level vs the group with the lowest level of poverty). Furthermore, multidimensional poverty was a confounding factor for the association between the percentage of the population living in rural areas and avoidable child mortality. CONCLUSIONS: Systematic and avoidable gaps were observed in mortality in children aged under 5 years in Colombia, where the territory constitutes an axis of inequality. Implementing strategies and programs that contribute to improving the conditions of women and socio-economic conditions in the territories should be a priority.

Effectiveness of contact tracing to reduce fatality from COVID-19: preliminary evidence from Colombia.

OBJECTIVES: Conducting contact tracing (CT) programs in low- and middle-income countries is challenging, and there is no evidence of their effectiveness in Latin America. We evaluated the effectiveness of CT on reducing fatality from COVID-19 in Colombia. STUDY DESIGN: The study design is a retrospective cohort study with nation-wide data of suspected and confirmed cases of severe acute respiratory syndrome (SARS-CoV-2) infection and their registered contacts. METHODS: We analyzed confirmed and suspected COVID-19 cases and their chains of contact using a nation-wide registry from March 28, 2020 to January 13, 2021. To estimate the effect of CT on fatality, we adjusted a multilevel negative binomial model using the number of deaths and the number of people within a chain of contacts as the outcome variable and offset variable, respectively. Sensitivity analysis was conducted using different cutoff values of contacts traced and a logistic model for the effect of CT on death at an individual level. RESULTS: We analyzed 1.4 million cases, 542,936 chains of contact, and 46,087 deaths. Only, 5.8% of total cases and contacts were included in a chain of a case and five or more contacts. We found that tracing of at least five contacts per case reduces fatality by 48% (95% confidence interval: 45-51), and, at the current levels of tracing in Colombia, it prevents 1.8% of deaths. Results obtained from the sensitivity analysis were consistent with the reduction of fatality at an individual level and higher protective effect with the higher number of contacts traced. CONCLUSIONS: In Colombia, tracing of at least five contacts per case reduces fatality from COVID-19. The coverage and intensity of tracing needs to be increased as a strategy to mitigate fatality in Colombia.

Study of the presence of spherical deformations on the Al top electrode due to electroforming in rewritable organic resistive memories.

Physical deformations are observed at the top electrodes during the electroforming process in Al/PEDOT:PSS + nitrogen doped multiwalled carbon nanotube (N-MWCNTs)/Al rewritable resistive memory devices. These physical deformations arise from electrochemical reactions, i.e., a reduction reaction in the native Al oxide layer, which are similar to those reported in TiO2-based resistive memory devices. These memory devices are electroformed at the ON state using an ∼-2 V pulse or at the OFF state using an ∼3 V pulse. These processes are current-controlled; a minimum compliance current is necessary to obtain the electroforming of the device, generally between 5 to 10 mA. SEM and AFM micrographs show the presence of spherical deformations at the top electrode due to O2 gas formation generated by the reduction in the native AlOx layer during the electroformation, with a diameter of ∼7 micrometres for positive voltage or a smaller diameter of ∼3 micrometres for negative voltage. After top-electrode delamination, circular craters are found in the active layer in the vicinity of the N-MWCNTs, which only occurs when a negative voltage is used in the electroformation, indicating that film damage is induced by oxygen bubbles created at the bottom electrode/polymeric film interface.

Across plane ionic conductivity of highly oriented neodymium doped ceria thin films.

A methodology to limit interfacial effects in thin films is proposed and explained. The strategy is to reduce the impact of the electrode interfaces and eliminate cross grain boundaries that impede ionic motion. To this end, highly oriented Nd0.1Ce0.9O2-δ (NDC) nanocrystalline thin films were grown using pulsed laser deposition (PLD) on platinized single crystal a-plane sapphire substrates. High resolution cross-sectional transmission electron microscopy (HR-XTEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) verified the films were textured with columnar grains. The average widths of the columns were approximately 40 nm and not significantly changed by film thickness between 100 and 300 nm. HR-XTEM and XRD determined the {111} planes of NDC were grown preferentially on top of the {111} planes of platinum despite the large lattice mismatch between the two planes. From the XRD patterns, the out of plane strains on the platinum and NDC layers were less than 1%. This can be explained by the coincident site lattice (CSL) theory. Rotating the {111} ceria planes 19.11° with respect to the {111} platinum planes forms a Σ7 boundary where 1 in 7 cerium lattice sites are coincident with the platinum lattice sites. This orientation lowers interfacial energy promoting the preferential alignment of those two planes. The across plane ionic conductivity was measured at low temperatures (<350 °C) for the various film thicknesses. It is here shown that columnar grain growth of ceria can be induced on platinized substrates allowing pathways that are clear of blocking grain boundaries that cause conductivities to diminish as film thickness decreases.

Er,Cr:YSGG laser therapy for oral leukoplakia minimizes thermal artifacts on surgical margins: a pilot study.

Laser use for biopsy of suspicious lesions may simulate cytological atypia at the margin of the incisions, challenging pathological diagnosis. Erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser has shown promising results in experimental models by inducing fewer artifacts. The aims of this study were to examine the thermal wounds induced by Er,Cr:YSGG laser in a short series of oral leukoplakias in terms of cytological and epithelial architectural changes and also to assess the width of the thermal damage lateral to the incision. Four oral leukoplakia patients entered the study and underwent complete surgical excision of their lesions by using Er,Cr:YSGG laser. Patients were weekly controlled until complete healing was accomplished. The patients were included on the existing follow-up program for these lesions thereafter. Study samples were routinely processed by the same technician and double-blindedly studied by two pathologists until a consensus was reached for each case. The pathological analysis of the samples revealed no autolysis and no fixation- or handling-related artifacts. However, cellular and nuclear polymorphism could be observed in two samples. Loss of intercellular adherence was the most frequent thermal artifact in this series; all pseudodysplastic artifacts recognized in the study were of low intensity and located at the basal and suprabasal layers of the leukoplakias' epithelium. The width of the thermal damage at the edge of the incision scored an average of 26.60 ± 25.3 µm. It is concluded that irradiation with Er,Cr:YSGG laser induces a minimal amount of thermal artifacts at the surgical margins of oral leukoplakias and avoids diagnostic interferences with real dysplastic borders.

[Magnet intestinal lesions. Case series]. / Lesiones intestinales por imanes. Serie de casos.

The ingestion of foreign bodies is a common trouble in the pediatric population, and most of cases occur between 6 months and 3 years. In general the vast majority of foreign bodies are not associated with morbidity or mortality. Ingestion of two or more magnets can lead to obstruction, fistulas, ulceration, perforation and bowel volvulus. In this series we present 4 cases of patients ingesting multiple magnets and who due to the ingested foreign body characteristics and clinical profile required surgical treatment.

Performance of public health surveillance systems during the influenza A(H1N1) pandemic in the Americas: testing a new method based on Benford's Law.

The A(H1N1) influenza pandemic has been a challenge for public health surveillance systems in all countries. An objective evaluation has not been conducted, as yet, of the performance of those systems during the pandemic. This paper presents an algorithm based on Benford's Law and the mortality ratio in order to evaluate the quality of the data and the sensitivity of surveillance systems. It analyses records of confirmed cases reported to the Pan American Health Organization by its 35 member countries between epidemiological weeks 13 and 47 in 2009. Seventeen countries did not fulfil Benford's Law, and mortality exceeded the regional average in 40% of the countries. The results suggest uneven performance by surveillance systems in the different countries, with the most frequent problem being low diagnostic coverage. Benford's Law proved to be a useful tool for the evaluation of a public health surveillance system's performance.

Congenital heart disease-associated liver disease: a narrative review.

Congenital heart diseases (CHD) can be associated with liver dysfunction. The cause for liver impairment can result out of a wide spectrum of different causes, including liver congestion, hypoxemia or low cardiac output. Fortunately, most CHD show a good long-term outcome from a cardiac perspective, but great attention should be paid on non-cardiac health problems that develop frequently in patients suffering from CHD. The treatment of liver dysfunction in CHD requires a close multidisciplinary management in a vulnerable patient collective. Unfortunately, structured recommendations on the management of liver dysfunction in patients with CHD are scarce. The objective of this review is to provide insights on the pathophysiology and etiologies of liver dysfunction as one of the most relevant non-cardiac problems related to CHD. Furthermore, we advise here on the management of liver disease in CHD with special attention on assessment of liver dysfunction, management of portal hypertension as well as on surveillance and management of hepatocellular carcinoma (HCC). A multidisciplinary perspective may help to optimize morbidity and mortality in the long-term course in these patients. However, as evidence is low in many aspects, we encourage the scientific community to perform prospective studies to gain more insights in the treatment of liver dysfunction in patients with CHD.

Clinical features and real-world outcomes of Guillain-Barré syndrome in the Philippines.

BACKGROUND: Our study aimed to determine the profile of Guillain-Barré syndrome (GBS) in the Philippines, compare the outcomes who received intravenous immunoglobulin (IVIg) and therapeutic plasma exchange (TPE), and determine the factors related to hospital stay and late motor recovery. METHODS: We conducted a retrospective cohort study of adult GBS patients admitted to the Philippine General Hospital from 2009 to 2019. RESULTS: We included 105 patients with confirmed GBS diagnoses. The median age was 43 years (interquartile range 32 to 56); the female-to-male ratio was 1.62:1; the predominant variant was acute inflammatory demyelinating polyneuropathy (n = 40, 38.1%). The difference in outcomes of patients in the IVIg (n = 44) and TPE (n = 24) groups (walking with aid/GBS-disability scores/ventilator dependency at 1 month, duration dependent on the ventilator, intensive care unit stay, and hospital stay) were not statistically significant, except for mild disability at 1 month (p = 0.009). Pneumonia, urinary tract infection, and dysautonomia were significantly related to a prolonged hospital stay. No predetermined variables were associated with late motor recovery. After adjusting for age and sex, the cumulative hazard risk for late motor recovery was 0.69 (95% CI 0.27-1.74). CONCLUSION: Our study presented the first comprehensive information regarding the features and outcomes of GBS patients in the Philippines. ABBREVIATIONS: AIDP - Acute inflammatory demyelinating polyneuropathy; AMAN - Acute motor axonal neuropathy; AMSAN - Acute motor and sensory axonal neuropathy; GBS - Guillain-Barré syndrome; GBS-DS - Guillain-Barré syndrome disability scale; ICU - Intensive care unit; IVIg - Intravenous immunoglobulin; MFS - Miller-Fisher syndrome; PGH - Philippine General Hospital; TPE - Therapeutic plasma exchange.

Scientific impact of multiple sclerosis and neuromyelitis optica spectrum disorder research from Southeast Asia: A bibliometric analysis.

BACKGROUND: Scientific productivity in the Southeast Asian (SEA) region in the field of multiple sclerosis and neuromyelitis optica spectrum disorder (MS/ NMOSD) was hypothesized to be low in magnitude. The aim of this study was to determine and compare MS/ NMOSD research outputs among the SEA countries in terms of established bibliometric indices. The association between these productivity indices and relevant country-specific socioeconomic factors was also determined. METHODS: A systematic review was conducted to include all relevant published MS/ NMOSD studies in the SEA indexed in MEDLINE, Embase, Scopus and CENTRAL from the inception of these databases to August 1, 2019. Quantity of research productivity was measured in terms of the total published documents. Quality of research impact was evaluated by assessing the study designs of the published reports, publications in journals with impact factor (IF) and PlumX Metrics (citations, usage, captures, mentions and social medias). Population size, gross domestic product (GDP) per capita, percentage (%) of GDP allocated to research and development (R&D), and the total number of neurologists reported in each country were obtained from reliable published data. RESULTS: Out of 3,547 articles identified, only 142 articles fulfilled the eligibility criteria; therefore, the total number of publications in the SEA region related to MS/ NMOSD was deemed low in quantity. Most studies were cross-sectional and case reports/ series; hence, most studies offered low level of evidence. Since the aggregate scores in citations, usage, captures, mentions, and social medias in PlumX Metrics and publications in journals with IF were low, the overall quality of the published articles was considered low. Thailand (57 articles), Malaysia (40) and Singapore (29) contributed to the majority of publications on the topic-. GDP per capita was statistically correlated with usage. Percent GDP for R&D was positively correlated with total publications, usage, captures and social mediaindices. CONCLUSION: In conclusion, the scientific impact of MS/ NMOSD in the SEA was considered low in quantity and quality. This study must encourage researchers in the SEA to produce greater volumes of high-quality publications in this particular field and motivate governments to increase % GDP for R&D for the benefit of patients suffering fromthese rare and disabling conditions.

Propranolol increases the complexity of heart rate fluctuations--a mode of antiarrhythmic action?

OBJECTIVE: To study the beta-blocking effect of propranolol on heart rate and arterial blood pressure fluctuations in healthy subjects using linear methods and a set of nonlinear models. METHODS: In a randomized, double-blind, placebo-controlled study, healthy young adults received a 40 mg oral dose of propranolol (n = 12) or placebo (n = 12). The effects of propranolol and placebo were assessed using time series of the RR interval (RRI) and systolic arterial blood pressure (SAP) obtained from continuous ECG and blood pressure signal recordings. Heart rate and systolic arterial blood pressure fluctuations were analyzed using nonlinear and linear methods of time series statistics. RESULTS: Propranolol significantly increased the complexity of heart rate fluctuations in terms of symbol dynamic (SymDyn) entropy and symbol dynamic percentage of forbidden words. Propranolol augmented cross entropy between RRI and SAP and increased fractal dimension of RRI. beta-blockade also affected linear measures of RRI fluctuations by increasing parasympathetic, respiration-related high-frequency (HF) variability and arterial baroreflex-related low-frequency (LF) variability. Propranolol administration, however, had no effect on the complexity of SAP fluctuations assessed using nonlinear time series statistics. CONCLUSIONS: beta-blockade by propranolol has a differential effect on RRI and SAP fluctuations in healthy subjects. Propranolol increases the complexity of RRI fluctuations. The effect is associated with the cardiac vagotonic drug action of propranolol. SAP fluctuations are almost unchanged. The increased complexity of RRI fluctuations may be a beneficial feature of beta-blockade, since many cardiovascular diseases decrease the complexity of RRI time series by dampening cardiovascular reflex actions.

Preparation of betulinic acid nanoemulsions stabilized by ω-3 enriched phosphatidylcholine.

Bioactive compounds such as ω-3 fatty acids and terpenes, have been associated with beneficial health effects; however, their solubility in the gastrointestinal tract and its bioavailability in the body are low. Nanoemulsions offer a viable alternative to disperse lipophilic compounds and improve their dissolution, permeation, absorption and bioavailability. Enzyme modified phosphatidylcholine (PC) with ω-3 fatty acids was used as emulsifier to stabilize oil-in-water nanoemulsions generated using ultrasound device. These systems were used as carriers of betulinic acid, which has reported anti-carcinogenic activity. Phospholipase-catalyzed modification of PC allowed the incorporation of 50 mol% of ω-3 fatty acids. Formation variables such as oil type and ultrasound amplitude had effects on nanoemulsion characteristics. Incorporation of betulinic acid affected globule size; however, betulinic acid nanoemulsions below 200 nm could be prepared. The conditions under which betulinic acid nanoemulsions were obtained using the modified phosphatidylcholine with the smaller globule size (91 nm) were 10% PC, 25% glycerol, medium chain oil and 30% amplitude for 12 min in the sonicator. Storage temperature had an effect on the stability of the nanoemulsions, at 5°C we observed the smallest growth in globule size. The use of olive oil decreased the globule size growth during storage of the nanoemulsion stabilized with modified phosphatidylcholine, although globule size obtained was greater than 200 nm. Medium pH had a significant effect on the nanoemulsions; alkaline pH values improved storage stability. These results provide useful information for using this type of carrier system on the formulation of products in the pharmaceutical or food industry.

An improved HPLC assay for S-2-(3-aminopropylamino)ethyl phosphorothioate (WR-2721) in plasma.

An HPLC assay is presented for the detection and quantitation of the radioprotective drug S-2-(3-aminopropylamino)ethyl phosphorothioate (WR-2721, ethiofos) present in plasma. Improved selectivity and a 40-fold increase in sensitivity have been demonstrated over the method previously reported by this laboratory. Using precolumn derivatization with fluorescamine and S-3-(4-aminobutylamino)propyl phosphorothioate (WR-80855, a homolog of WR-2721) as the internal standard, drug levels of 0.05 to 1000 micrograms/mL were determined with excellent precision (CV less than or equal to 5% over the concentration range). An isocratic mobile phase of acetonitrile/ethanol/water (16:7:77) modified with 0.01 M tetrabutylammonium phosphate eluted the drug and the internal standard from the C-18 reverse-phase column in 23 minutes and 26 minutes, respectively. Detector response was linear over the entire range. The assay uses 150 microL of plasma and requires a total chromatography time of about 50 minutes. The method was found suitable for pharmacokinetic studies in a preliminary experiment with a beagle dog in which no interferences due to plasma constituents or drug metabolites were observed.

Cardiovascular effects of ophthalmic 0.5% timolol aqueous solution and 0.1% timolol hydrogel.

The objective of this randomized, double-masked, cross-over study was to compare the cardiovascular effects of two glaucoma formulations, ophthalmic 0.5% timolol aqueous solution and 0.1% timolol hydrogel. Twenty-four young healthy subjects received for 2 weeks either twice daily 0.5% timolol solution or once daily 0.1% timolol hydrogel. Heart rate (HR), blood pressure, atrio-ventricular conduction (PR interval), corrected QT time (QTc) and heart rate variability (HRV) were measured in supine position and during head-up tilted position. The mean peak concentrations of timolol in plasma were significantly higher after administration of 0.5% aqueous solution than after 0.1% hydrogel. A 0.5% timolol aqueous solution decreased HR on average by 3 bpm in supine position and by 7 bpm in head-up tilted position while no significant effects were observed with 0.1% timolol hydrogel. During tilt test HR was significantly lower after administration of timolol aqueous solution than after timolol hydrogel (mean +/- SD, 77 +/- 11 bpm versus 86 +/- 13 bpm, P < 0.05). Timolol aqueous solution slightly decreased QTc during tilt (5.9 +/- 5.6 ms, P < 0.01). During tilt tests, timolol aqueous solution slightly increased atrio-ventricular conduction (7.2 ms, P = 0.02). No significant differences were found in HRV. These results indicate that in healthy volunteers, ophthalmic 0.5% timolol aqueous solution produces more pronounced cardiac beta-blocking effects than 0.1% timolol hydrogel.