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The crisis caused by the COVID-19 outbreak around the globe raised an increasing concern about the ongoing emergence of variants of the virus that may evade the immune response provided by vaccines. New variants appear due to mutation, and as the cases accumulate, the probability of the emergence of a variant of concern increases. In this article, we propose a modified susceptible, infected, and recovered (SIR) model with waning immunity that captures the competition of two strain classes of an infectious disease under the effect of vaccination with a highly contagious and deadlier strain class emerging from a prior strain due to mutation. When these strains compete for a limited supply of susceptible individuals, changes in the efficiency of vaccines may affect the behaviour of the disease in a non-trivial way, resulting in complex outcomes. We characterise the parameter space including intrinsic parameters of the disease, and using the vaccine efficiencies as control variables. We find different types of transcritical bifurcations between endemic fixed points and a disease-free equilibrium and identify a region of strain competition where the two strain classes coexist during a transient period. We show that a strain can be extinguished either due to strain competition or vaccination, and we obtain the critical values of the efficiency of vaccines to eradicate the disease. Numerical studies using parameters estimated from publicly reported data agree with our theoretical results. Our mathematical model could be a tool to assess quantitatively the vaccination policies of competing and emerging strains using the dynamics in epidemics of infectious diseases.
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Introducción: El cuestionario "Assessment of Spondyloarthritis International Society Health Index" (ASAS-HI) fue desarrollado para medir de manera global la funcionalidad y el estado de salud en pacientes con espondiloartritis (EspA). Se han propuesto puntos de corte para determinar diferentes estados de salud que fueron poco evaluados en pacientes de la vida real. Objetivos: Describir el estado de salud medido por ASAS-HI en pacientes argentinos con EspA axial (EspAax) y periférica (EspAp) en la práctica diaria y evaluar los factores asociados al pobre estado de salud. Materiales y métodos: Estudio de corte transversal, analítico y multicéntrico. Se incluyeron consecutivamente pacientes con EspAax y EspAp según criterios ASAS, de 15 centros argentinos. Análisis estadístico: Se realizó estadística descriptiva, análisis bivariado y multivariado (regresión logística múltiple) para evaluar los factores asociados al pobre estado de salud (ASAS-HI ≥12). Para analizar la validez de constructo de la herramienta se realizó correlación de Spearman entre el ASAS-HI y otros parámetros de evaluación de la enfermedad. Resultados: Se incluyeron 274 pacientes con EspA, con una edad media de 49 (±14) años y una duración mediana de la enfermedad de 62 meses (p25-75: 24-135), 155 (56,6%) de los pacientes eran de sexo masculino, 129 pacientes (47%) con EspAax y 145 (52,9%) EspAp. Según el ASAS-HI 119 pacientes (43,4%) presentaban buen estado de salud, 117 (42,7%) tenían estado de salud moderado y 38 (13.9%) pobre estado de salud. En los pacientes con EspAp el valor de ASAS-HI mediano fue de 7 (p25-75: 3-10). El ASAS-HI correlacionó positivamente con: DAS28: rho: 0.5 (p<0.001) y HAQ: rho: 0.54 (p<0.001). La variable asociada de manera independiente con pobre estado de salud fue el DAS28 (OR: 1.9, IC95% 1.1-3.4, p: 0.029). En los pacientes con EspAax el valor de ASAS-HI mediano fue de 6 (p25-75: 2.75-10). El ASAS-HI mostró correlación con: BASDAI: rho: 0.7 (p<0.001), ASDAS-ERS: rho: 0.7 (p<0,001), ASQoL: rho: 0.8 (p<0.001), BASFI rho: 0.75 (p<0.001). La variable que se asoció de manera independiente a pobre estado de salud fue el ASDAS-ERS (OR 6.6, IC95% 2-22, p 0.002). Conclusión: Un pobre estado de salud se asoció independientemente a mayor actividad de la enfermedad en pacientes con EspAax y EspAp. El ASAS-HI correlacionó con otros parámetros de la enfermedad, lo que refuerza la validez de constructo de esta nueva herramienta.
Introduction: The "Assessment of Spondyloarthritis International Society Health Index" (ASAS-HI) questionnaire was developed to globally measure function and health status in patients with spondyloarthritis (SpA). Cut-off points have been proposed to determine different health states that were poorly evaluated in real-life patients. Objectives: To describe the health status measured by ASAS-HI in Argentine patients with axial SpA (AxSpA) and peripheral SpA (SpAp) in daily practice and to evaluate the factors associated with poor health. Materials and methods: Cross-sectional, analytical and multicenter study. Patients with SpAax and SpAp were consecutively included according to ASAS criteria, from 15 Argentine centers. Statistical analysis: Descriptive statistics, bivariate and multivariate analysis (multiple logistic regression) were performed to evaluate the factors associated with poor health status (ASAS-HI ≥12). To analyze the construct validity of the tool, Spearman correlation was performed between the ASAS-HI and other disease evaluation parameters. Results: 274 patients with SpA were included, with a mean age of 49 (± 14) years and a median duration of the disease of 62 months (p25-75: 24-135), 155 (56.6%) were male, 129 patients (47%) with AxSpA and 145 (52.9%) SpAp. According to the ASAS-HI, 119 patients (43.4%) had good health, 117 (42.7%) had moderate health and 38 (13.9%) had poor health. In patients with SpAp, the mean ASAS-HI value was 7 (p25-75: 3-10). The ASAS-HI positively correlated with: DAS28: rho: 0.5 (p <0.001) and HAQ: rho: 0.54 (p <0.001). The variable independently associated with poor health status was DAS28 (OR: 1.9, 95% CI 1.1-3.4, p: 0.029). In patients with AxSpA, the mean ASAS-HI value was 6 (p25-75: 2.75-10). The ASAS-HI showed correlation with: BASDAI: rho: 0.7 (p <0.001), ASDAS-ERS: rho: 0.7 (p <0.001), ASQoL: rho: 0.8 (p <0.001), BASFI rho: 0.75 (p <0.001). The variable that was independently associated with poor health was the ASDAS-ERS (OR 6.6, 95% CI 2-22, p 0.002). Conclusion: Poor health status was independently associated with higher disease activity in patients with AxSpA and SpAp. The ASAS-HI correlated with other parameters of the disease, which reinforces the construct validity of this new tool.
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Espondilartrite , Nível de Saúde , Questionário de Saúde do PacienteRESUMO
BACKGROUND: Apical periodontitis (AP) frequently presents as a chronic asymptomatic disease. To arrive at a true diagnosis, in addition to the clinical examination, it is mandatory to undertake radiographic examinations such as periapical or panoramic radiographs, or cone-beam computed tomography (CBCT). Thus, the worldwide burden of AP is probably underestimated or unknown. Previous systematic reviews attempted to estimate the prevalence of AP, but none have investigated which factors may influence its prevalence worldwide. OBJECTIVES: To assess: (i) the prevalence of AP in the population worldwide, as well as the frequency of AP in all teeth, nontreated teeth and root filled teeth; (ii) which factors can modify the prevalence of AP. METHODS: A search was conducted in the PubMed-MEDLINE, EMBASE, Cochrane-CENTRAL, LILACS, Google scholar and OpenGrey databases, followed by hand searches, until September 2019. Cross-sectional, case-control and cohort studies reporting the prevalence of AP in humans, using panoramic or periapical radiograph or CBCT as image methods were included. No language restriction was applied. An adaptation of the Newcastle-Ottawa Scale was used to evaluate the quality of the studies. A meta-analysis was performed to determine the pooled prevalence of AP at the individual level. Secondary outcomes were the frequency of AP in all teeth, nontreated teeth and rootfilled teeth. Subgroup analyses using random-effect models were carried out to analyse the influence of explanatory covariables on the outcome. RESULTS: The search strategy identified 6670 articles, and 114 studies were included in the meta-analysis, providing data from 34 668 individuals and 639 357 teeth. The prevalence of AP was 52% at the individual level (95% CI 42%-56%, I2 = 97.8%) and 5% at the tooth level (95% CI 4%-6%; I2 = 99.5%). The frequency of AP in root-filled teeth and nontreated teeth was 39% (95% CI 36%-43%; I2 = 98.5%) and 3% (95% CI 2%-3%; I2 = 99.3%), respectively. The prevalence of AP was greater in samples from dental care services (DCS; 57%; 95% CI 52%-62%; I2 = 97.8%) and hospitals (51%; 95% CI 40%-63%; I2 = 95.9%) than in those from the general population (GP; 40%; 95% CI 33%-46%; I2 = 96.5%); it was also greater in people with a systemic condition (63%; 95% CI 56%-69%, I2 = 89.7%) compared to healthy individuals (48%; 95% CI 43%-53%; I2 = 98.3%). DISCUSSION: The subgroup analyses identified explanatory factors related to the variability in the prevalence of AP. However, the high clinical heterogeneity and high risk of bias across the primary studies indicate that the findings must be interpreted with caution. CONCLUSIONS: Half of the adult population worldwide have at least one tooth with apical periodontitis. The prevalence of AP is greater in samples from the dental care services, but it is also high amongst community representative samples from the general population. The present findings should bring the attention of health policymakers, medical and dental communities to the hidden burden of endodontic disease in the population worldwide.
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Periodontite Periapical , Dente não Vital , Adulto , Estudos Transversais , Humanos , Periodontite Periapical/diagnóstico por imagem , Periodontite Periapical/epidemiologia , Prevalência , Obturação do Canal Radicular , Tratamento do Canal RadicularRESUMO
The brachiocephalic trunk and the left subclavian artery originate from the aortic arch, and both supply blood to the head, neck, and thoracic limbs. Anatomical variations, such as an aberrant right subclavian artery, are congenital conditions rarely observed in dogs, Thus, the objective of the present report was to describe a case of aberrant right subclavian artery in a 9-year-old Dalmatian. However, this anomaly was a finding in which the patient was asymptomatic during its 9 years of life and only at this age did he exhibit signs including sialorrhea, vomiting, hyporexia, and noisy deglutition. Blood count, biochemical profile, and thoracic radiography led to a diagnosis of megaesophagus and aspiration pneumonia. Despite the recommended treatment, the patient did not respond well; as such, the owner elected to euthanize the animal. On necropsy, the right subclavian artery originated directly from the aortic arch, followed a route from left to right dorsally to the esophagus, and then formed an impression of the vascular path over the muscular wall of the esophagus. The esophagus, in turn, exhibited a flaccid wall and dilation in the caudal portion to the vascular path made by the ectopic position of the right subclavian artery.(AU)
O tronco braquiocefálico e a artéria subclávia esquerda emergem do arco aórtico e são responsáveis por fazerem o suprimento sanguíneo para cabeça, pescoço e membros torácicos. Variações anatômicas, como a ectopia da artéria subclávia direita, são alterações congênitas raramente encontradas em cães, cujas alterações do sistema digestivo acontecem em pacientes recém-desmamados e não em adultos. Assim, o objetivo deste relato é descrever um caso de ectopia da artéria subclávia direita em uma cadela, Dálmata, de nove anos de idade. No entanto, essa anomalia foi um achado do qual o paciente foi assintomático durante os nove anos de vida e somente com essa idade apresentou sinais como sialorreia, vômito, hiporexia e deglutição ruidosa. O hemograma e os perfis bioquímicos, associados à radiografia torácica, levaram a um diagnóstico de megaesôfago e pneumonia aspirativa. Mesmo seguindo o tratamento recomendado, houve piora clínica do quadro e o animal foi submetido à eutanásia. À macroscopia, a artéria subclávia direita originava-se direto do arco aórtico, fazia um percurso da esquerda para a direita dorsalmente ao esôfago e, então, formava uma impressão do trajeto vascular sobre a parede muscular do esôfago. O esôfago, por sua vez, apresentava parede flácida e dilatação na porção caudal ao trajeto vascular feito pela posição ectópica da artéria subclávia direita.(AU)
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Animais , Feminino , Cães , Artéria Subclávia/anatomia & histologia , Artéria Subclávia/anormalidades , Anormalidades Congênitas/veterinária , Acalasia Esofágica/veterináriaRESUMO
In this work was to evaluate the conidiospores production of Trichoderma harzianum using barley straw as substrate. Four growth conditions were used; washed and unwashed barley straw and washed and unwashed barley straw supplemented with mineral salts. The highest spore production was observed when washed barley straw supplemented with mineral salts with 1.56â¯×â¯1010 conidiospores/gram of dry matter (gdm) at 216â¯h of cultivation was used. The effect of substrate moisture on spore production was studied, three initial moisture levels of the substrate were tested and it was observed that a humidity of 80 % of the substrate improves the production of conidiospores reaching a concentration of 2.35â¯×â¯1010 conidiospores/gdm at 136â¯h. Finally, conidiospores viability was evaluated for 12 months by keeping them on the conidia and substrate, and viability of 71 % of the conidiospores was observed, so this maintenance method is an excellent means of conserving the conidiospores viability.
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The objective of the present study was to determine the susceptibility of entomopathogenic nematodes to ivermectin and thiabendazole. Soil samples collected from the municipalities of Irapuato and León, Guanajuato, Mexico, were obtained, from which the entomopathogenic nematodes (EPNs) of the Steinernematidae and Heterorhabditidae families were isolated. The samples were classified from livestock and nonlivestock soils, and the susceptibility of EPNs to anthelmintics was determined with the larval motility assay (LMA, 24 h) and the larval migration inhibition assay (LMI assay, 48 h). Sterile distilled water (T1) and treatments with 1% ivermectin diluted in 5% DMSO (dimethyl sulfoxide) (T2) and 5% thiabendazole diluted in 5% DMSO (T3) were applied to infective juvenile larvae. Analysis of variance was performed with a factorial design and Tukey's test at 0.05 probability. In addition, different concentrations of ivermectin (0.1, 0.5, 1, 1.2, 1.5, and 2 µg) and thiabendazole (1, 5, 10, 12, 15, and 20 mg) were evaluated to perform a Probit analysis to determine their LC50. All strains of EPNs were susceptible to ivermectin in both the LMA and LMI assay. The results show that EPNs are susceptible to ivermectin and thiabendazole, and the degree depends on the type of test performed, the chemical product used, and the origin of the strain of EPN.
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Anti-Helmínticos/toxicidade , Ivermectina/toxicidade , Rabditídios/fisiologia , Tiabendazol/toxicidade , Animais , Larva/efeitos dos fármacos , México , SoloRESUMO
Chondrosarcoma is a malignant tumor which often affects the pelvic ring and its symptomathology is non-specific and insidious. We display a case of a right iliopubic branch chondrosarcoma in a 62-year-old male whose first sing was a four-year history of sporadic macroscopic haematuria, related to efforts. After being studied by the Urology Department by cystoscopy and biopsy of bladder tumor, chondral cells were appreciated. Further study with imaging tests diagnosed low-grade chondrosarcoma with bladder infringement. The case is assessed by Musculoskeletal Tumors Committee and a multidisciplinary approach is carried out through en bloc resection and pelvic floor reconstruction. Currently the patient remains asymptomatic.
El condrosarcoma es un tumor maligno que afecta con frecuencia la pelvis y su sintomatología es inespecífica e insidiosa. Describimos el caso de un condrosarcoma de la rama iliopubiana derecha en un varón de 62 años cuyo primer signo de aparición fue una hematuria macroscópica esporádica, relacionada con esfuerzos y de cuatro meses de evolución. Tras ser estudiado por el servicio de urología mediante cistoscopía con biopsia de tumoración en pared vesical se aprecian células de estirpe condral. Tras posterior estudio con pruebas de imagen se diagnostica condrosarcoma de bajo grado con invasión de la vejiga, por lo que es valorado en el comité de tumores musculoesqueléticos y se realiza un abordaje multidisciplinar mediante exéresis en bloque y reconstrucción del suelo pélvico. Actualmente el paciente continúa asintomático.
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Neoplasias Ósseas , Condrossarcoma , Procedimentos de Cirurgia Plástica , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Condrossarcoma/diagnóstico , Condrossarcoma/diagnóstico por imagem , Hematúria , Humanos , Masculino , Pessoa de Meia-Idade , Pelve/cirurgiaRESUMO
Resumen La actina es una proteína que se polimeriza para formar citoesqueletos y cuya función es estabilizar y dirigir el movimiento de las paredes celulares. Es una de las proteínas más estables, habiendo evolucionado poco a partir de algas y levaduras, y muy poco desde los peces. Aquí analizamos la evolución de la actina usando las teorías modernas de las interacciones de conformación proteína-agua, y cómo estas han evolucionado para optimizar las funciones de la proteína. Llegamos a la conclusión de que el fracaso del análisis filogenético para identificar positivamente la evolución darwiniana de las proteínas ha sido causado por las limitaciones técnicas propias del siglo XX. Estas limitaciones pueden ser superadas mediante el escalamiento termodinámico y el promedio modular ambos llevados a niveles técnicos del siglo XXI. Los resultados para la actina son especialmente llamativos y reflejan estructuras duales estables, globulares y polimerizadas.
Abstract Actin polymerizes to form cytoskeletons which stabilize and direct motion of cellular walls. It is one of the most stable proteins, having evolved little from algae and yeast, and very little from fish. Here we analyze actin evolution using modern theories of water-protein shaping interactions, and how these have evolved to optimize protein functions. We conclude that the failure of phylogenetic analysis to identify positive Darwinian evolution has been caused by 20th century technical limitations. These are overcome using 21st century thermodynamic scaling and modular averaging. The results for actin are especially striking, and reflect dual stable structures, globular and polymerized.
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Vicuñas and guanacos are two species of wild South American camelids that are key ruminants in the ecosystems where they occur. Although closely related, these species feature differing ecologies and life history characters, which are expected to influence both their genetic diversity and population differentiation at different spatial scales. Here, using mitochondrial and microsatellite genetic markers, we show that vicuña display lower genetic diversity within populations than guanaco but exhibit more structure across their Peruvian range, which may reflect a combination of natural genetic differentiation linked to geographic isolation and recent anthropogenic population declines. Coalescent-based demographic analyses indicate that both species have passed through a strong bottleneck, reducing their effective population sizes from over 20,000 to less than 1000 individuals. For vicuña, this bottleneck is inferred to have taken place ~3300 years ago, but to have occurred more recently for guanaco at ~2000 years ago. These inferred dates are considerably later than the onset of domestication (when the alpaca was domesticated from the vicuña while the llama was domesticated from the guanaco), coinciding instead with a major human population expansion following the mid-Holocene cold period. As importantly, they imply earlier declines than the well-documented Spanish conquest, where major mass mortality events were recorded for Andean human and camelid populations. We argue that underlying species' differences and recent demographic perturbations have influenced genetic diversity in modern vicuña and guanaco populations, and these processes should be carefully evaluated in the development and implementation of management strategies for these important genetic resources.
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Camelídeos Americanos/genética , Demografia , Variação Genética , Genética Populacional , Animais , Chile , Análise por Conglomerados , DNA Mitocondrial , Frequência do Gene , Loci Gênicos , Marcadores Genéticos , Haplótipos , Repetições de Microssatélites , PeruRESUMO
Open abdomen has been an effective treatment for abdominal catastrophes in trauma and general surgery, is one of the greatest advances in recent decades and has become a common procedure in both trauma and general surgery. Temporary abdominal closure techniques in managing open abdomen help to achieve many benefits without incurring many complications. We present a series of patients in which a temporary abdominal closure technique was used that generates continuous medial fascial traction dynamic in patients with open abdomen for different causes.