RESUMEN

This paper proposes and analyzes an immune-structured population model of tilapia subject to Tilapia Lake Virus (TiLV) disease. The model incorporates within-host dynamics, used to describe the interaction between the pathogen, the immune system and the waning of immunity. Individuals infected with a low dose acquire a low immunity level and those infected with a high dose acquire a high level of immunity. Since individuals' immune status plays an important role in the spread of infectious diseases at the population level, the within-host dynamics are connected to the between-host dynamics in the population. We define an explicit formula for the reproductive number [Formula: see text] and show that the disease-free equilibrium is locally asymptotically stable when [Formula: see text], while it is unstable when [Formula: see text]. Furthermore, we prove that an endemic equilibrium exists. We also study the influence of the initial distribution of host resistance on the spread of the disease, and find that hosts' initial resistance plays a crucial role in the disease dynamics. This suggests that the genetic selection aiming to improve hosts' initial resistance to TiLV could help fight the disease. The results also point out the crucial role played by the inoculum size. We find that the higher the initial inoculum size, the faster the dynamics of infection. Moreover, if the initial inoculum size is below a certain threshold, it may not result in an outbreak at the between-host level. Finally, the model shows that there is a strong negative correlation between heterogeneity and the probability of pathogen invasion.

Asunto(s)

RESUMEN

The diagnosis of tuberculosis (TB) in children is difficult because of the low sensitivity and specificity of traditional microbiology techniques in this age group. Whereas in adults the culture of Mycobacterium tuberculosis (M. tuberculosis), the gold standard test, detects 80% of positive cases, it only detects around 30-40% of cases in children. The new methods based on the immune response to M. tuberculosis infection could be affected by many factors. It is necessary to evaluate the medical record, clinical features, presence of drug-resistant M. tuberculosis strains, comorbidities, and BCG vaccination history for the diagnosis in children. There is no ideal biomarker for all TB cases in children. A new strategy based on personalized diagnosis could be used to evaluate specific molecules produced by the host immune response and make therapeutic decisions in each child, thereby changing standard immunological signatures to personalized signatures in TB. In this way, immune diagnosis, prognosis, and the use of potential immunomodulators as adjunct TB treatments will meet personalized treatment.

RESUMEN

Determination of antibodies against ToRCH antigens at the beginning of pregnancy allows assessment of both the maternal immune status and the risks to an adverse pregnancy outcome. Age-standardised seroprevalences were determined in sera from 1009 women of childbearing age residing in Mexico, Brazil, Germany, Poland, Turkey or China using a multiparametric immunoblot containing antigen substrates for antibodies against Toxoplasma gondii, rubella virus, cytomegalovirus (CMV), herpes simplex viruses (HSV-1, HSV-2), Bordetella pertussis, Chlamydia trachomatis, parvovirus B19, Treponema pallidum and varicella zoster virus (VZV). Seroprevalences for antibodies against HSV-1 were >90% in samples from Brazil and Turkey, whereas the other four countries showed lower mean age-adjusted seroprevalences (range: 62.5-87.9%). Samples from Brazilian women showed elevated seroprevalences of antibodies against HSV-2 (40.1%), C. trachomatis (46.8%) and B. pertussis (56.6%) compared to the other five countries. Seroprevalences of anti-T. gondii antibodies (0.5%) and anti-parvovirus B19 antibodies (7.5%) were low in samples from Chinese women, compared to the other five countries. Samples from German women revealed a low age-standardised seroprevalence of anti-CMV antibodies (28.8%) compared to the other five countries. These global differences in immune status of women in childbearing age advocate country-specific prophylaxis strategies to avoid infection with ToRCH pathogens.

Asunto(s)

RESUMEN

Introducción: El pie diabético es una alteración clínica inducida por la hiperglucemia mantenida, con o sin isquemia y previo traumatismo, lesión y/o ulceración del pie. La hiperglucemia favorece las infecciones, pero no potencia el crecimiento bacteriano, lo que sugiere la participación del sistema inmune en esta susceptibilidad. Objetivo: Caracterizar el estado inmunometabólico de los pacientes con diagnóstico pie diabético. Métodos: Se realizó un estudio descriptivo de corte transversal en 25 pacientes ingresados con diagnóstico de pie diabético, entre septiembre y diciembre de 2018 en el Hospital Universitario "Manuel Ascunce Domenéch". Las variables estudiadas fueron: edad, sexo, formas clínicas de presentación del pie diabético, complementos 3 y 4, inmunoglobulinas G y A, y hemoglobina glucosilada. Se empleó la estadística descriptiva para el análisis de los datos. Resultados: El sexo femenino representó el 60 por ciento y los pacientes con más de 70 años el 40 por ciento. La inmunoglobulina G sérica se encontró disminuida en un 28 por ciento de los pacientes con pie diabético y aumentada en otro 28 por ciento. La hemoglobina glucosilada reflejó un desbalance en el 48 por ciento de los casos. De los pacientes con descontrol metabólico, 8 (32 por ciento) mostraron alteraciones de la inmunoglobulina G y 2 del componente C3. Conclusiones: Existió un grupo de pacientes con pie diabético que presentaron alteraciones inmunológicas variables y/o descontrol metabólico. Estos podrían beneficiarse con un manejo integral a partir del uso de inmunoterapia y la prevención de complicaciones infecciosas del pie diabético(AU)

Introduction: Diabetic foot is a clinic alteration induced by persistent hyperglycemias, with or without ischemia and previous trauma, lesion and/or ulceration of the foot. Hyperglycemia favours infections, but it does not increase the bacterial growth which suggests the participation of the immune system in this sensitivity. Objective: To characterize the immunometabolic status of patients with diagnosis of diabetic foot. Methods: It was carried out a descriptive, cross-sectional study in 25 patients hospitalized with diagnosis of diabetic foot among September and December, 2018 in "Manuel Ascunce Domenech" University Hospital. The studied variables were: age, sex, clinical forms of diabetic foot, complement 3 and 4, G and A, immunoglobulins and glycosylated hemoglobine. It was used descriptive statistic for data analysis. Results: Females represented the 60 percent and patients older than 70 years were the 40 percet. Seric G immunoglobulin was found as decreased in 28 percent of the patients with diabetic foot and increased in the 28 percent. Glycosylated hemoglobine presented unbalanced in 48 percent of the cases. From the patients with metabolic decontrol, 8 (32 percent) showed alterations of G immunoglobulin and 2 in the component C3. Conclusions: There was a group of patients with diabetic foot who presented variable immunological alterations and/or metabolic decontrol. Those patients can benefit with an integral management using immunotherapy and the prevention of infectious complications of the diabetic foot(AU)

Asunto(s)

Asunto(s)

RESUMEN

This experiment was conducted to study the effects of arginine supplementation on organ development, egg quality, blood parameters, and immune status of laying hens. A total of 360 25-week-old brown Leghorn laying hens were randomly divided into three groups with six replicates of 20 birds each and fed diets supplemented with 0, 8.5, or 17 mg of L-arginine/kg for 42 days. Results showed that the weight of proventriculus and duodenum in the treatment supplemented with 17 mg/kg L-arginine was heavier than that of 0 mg L-arginine/kg treatment (p 0.05). The weight of oviduct in the treatments supplemented with 17 mg/kg L-arginine was smaller than that of 0 and 8.5 mg L-arginine/kg treatment (p 0.05), and the small yellow follicle amount in the treatment supplemented with 17 mg/kg L-arginine was less than that of 0 mg L-arginine/kg treatment (p 0.05), while its yolk color was deeper than that of 0 mg L-arginine/kg treatment (p 0.05), and the IgY content showed the same tendency. Total cholesterol and triglyceride levels in the treatment supplemented with 8.5 mg/kg L-arginine were lower than that of 0 mg L-arginine/kg treatment (p 0.05). The concentration of IL-2 in the treatment supplemented with 17 mg/kg L-arginine were more than that of 0 mg L-arginine/kg treatment (p 0.05). The findings of this study show that 17 mg/kg L-arginine supplementation has beneficial effects onlayers' immune status and yolk IgY content, as well as on proventriculus and duodenum weight while no adverse effects were observed on laying performance, egg quality, or blood parameters.

Asunto(s)

RESUMEN

This experiment was conducted to study the effects of arginine supplementation on organ development, egg quality, blood parameters, and immune status of laying hens. A total of 360 25-week-old brown Leghorn laying hens were randomly divided into three groups with six replicates of 20 birds each and fed diets supplemented with 0, 8.5, or 17 mg of L-arginine/kg for 42 days. Results showed that the weight of proventriculus and duodenum in the treatment supplemented with 17 mg/kg L-arginine was heavier than that of 0 mg L-arginine/kg treatment (p 0.05). The weight of oviduct in the treatments supplemented with 17 mg/kg L-arginine was smaller than that of 0 and 8.5 mg L-arginine/kg treatment (p 0.05), and the small yellow follicle amount in the treatment supplemented with 17 mg/kg L-arginine was less than that of 0 mg L-arginine/kg treatment (p 0.05), while its yolk color was deeper than that of 0 mg L-arginine/kg treatment (p 0.05), and the IgY content showed the same tendency. Total cholesterol and triglyceride levels in the treatment supplemented with 8.5 mg/kg L-arginine were lower than that of 0 mg L-arginine/kg treatment (p 0.05). The concentration of IL-2 in the treatment supplemented with 17 mg/kg L-arginine were more than that of 0 mg L-arginine/kg treatment (p 0.05). The findings of this study show that 17 mg/kg L-arginine supplementation has beneficial effects onlayers' immune status and yolk IgY content, as well as on proventriculus and duodenum weight while no adverse effects were observed on laying performance, egg quality, or blood parameters.(AU)

Asunto(s)

RESUMEN

Antibodies to Enterovirus 71 (EV71) were evaluated in São Paulo State during 1999-2005. The titer of neutralizing antibodies against EV71 was determined by microneutralization assay, and a titer of > 1:8 was defined as indicative of protected immunity. Neutralizing antibodies to EV71 were observed in 12.4 percent (55/442) of sera samples, a low protective rate, suggesting that EV71 infection is uncommon in this region, but that there is a relatively high susceptibility to EV71 related diseases, which is worrying considering the recent Asian outbreaks. Also, a significant location-specific difference in seropositivity was observed. Neutralizing antibodies to EV71 were observed in 8.7 percent (21/241) of São Paulo metropolitan area sera samples, and 16.9 percent (34/201) of the sera samples from other municipalities. A high number of Brazilian residents live in country and coastal areas without adequate access to piped water or sanitation. This situation may contribute to the EV71 dissemination in these zones. The analysis of environmental samples could possibly make a valuable contribution to studies on the epidemiology of EV71.

Anticorpos para Enterovírus 71 (EV71) foram avaliados no Estado de São Paulo durante 1999-2005. O título de anticorpos neutralizantes contra EV71 foi determinado pelo ensaio microneutralização, e um título de > 1:8 foi definido como indicador de imunidade protetora. Anticorpos neutralizantes para EV71 foram observados em 12,4 por cento (55/442) das amostras de soro, uma baixa taxa de proteção, sugerindo que a infecção pelo EV71 é incomum nesta região e que existe alta susceptibilidade a doenças relacionadas ao EV71, o que é preocupante considerando os recentes surtos asiáticos. Ainda, foi observada diferença significativa na soropositividade em relação à localização, onde 8,7 por cento (21/241) e 16,9 por cento (34/201) das amostras provenientes da região metropolitana de São Paulo, e demais municípios, respectivamente, apresentaram anticorpos neutralizantes para EV71. Um grande número de brasileiros vive em áreas rurais e à beira-mar, sem acesso adequado à água encanada ou saneamento. Essa situação pode contribuir para a disseminação de EV71 nessas regiões. A análise de amostras ambientais poderia gerar contribuição valiosa para estudos sobre a epidemiologia da EV71.

Asunto(s)