A model for preservation of thymocyte-depleted thymus.

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

Identification of APOB variants in samples from the brazilian population with hypercholesterolemic phenotype

BACKGROUND AND AIMS: Apolipoprotein B plays a crucial role in regulating plasma cholesterol by mediating the interaction of low-density lipoprotein (LDL) with LDL receptors in the liver. Inherited mutations in this gene may increase the risk of developing premature atherosclerotic cardiovascular disease, especially in individuals with familial hypercholesterolemia type 2 (FH2). The aim of this study is to identify APOB variants that may indicate pathogenicity in a sample of the Brazilian population using a data bank exome sequencing study by NGS in a Brazilian population phenotypically diagnosed by clinical and laboratory profile. This finding is going to improve genetic hypercholesteremia diagnosis. METHODS: High-quality DNA samples (n»300) were sequenced using an exon-targeted gene sequencing (ETGS) strategy to identify variants in FHrelated genes. Pathogenicity classification was based on criteria established by the American College of Medical Genetics and Genomics (ACMG), also using information from ClinVar and pathogenicity scores from previous association studies. RESULTS: A total of 121 variants were identified in APOB, of which four are novel variants missense (p.Thr626Asn, p.Ile2750Thr, p.Gln2078Lys and p.Met4184Arg). After curating pathogenicity scores, variants were classified according to the ACMG criteria. Among them four as pathogenic or likely pathogenic (p.Pro2739Leu, p.His1923Arg, p.Pro994Leu and p.Pro877Leu), and 21 variants had uncertain significance. Additionally, 92 previously known variants with uncertain significance were classified as benign or likely benign. The results were submitted to Clinvar for actualization of pathogenicity. CONCLUSIONS: These results improve the molecular diagnosis associating APOB variants with the clinical phenotype of hypercholesterolemia.

Antifungal activity of terpenes isolated from the Brazilian Caatinga: a review.

Terpenoids, also named terpenes or isoprenoids, are a family of natural products found in all living organisms. Many plants produce terpenoids as secondary metabolites, and these make up a large part of essential oils. One of most important characteristic is that the compounds are volatile, have odor and can be used in a variety of applications in different industrial segments and traditional medicine. Brazil has a rich and diverse flora that can be used as a source of research for obtaining new molecules. Within the Brazilian flora, it is worth mentioning the Caatinga as an exclusively Brazilian biome where plants adapt to a specific series of weather conditions and therefore become a great storehouse of the terpenoid compounds to be described herein. Fungal infections have become increasingly common, and a great demand for new agents with low toxicity and side effects has thus emerged. Scientists must search for new molecules exhibiting antifungal activity to develop new drugs. This review aims to analyze scientific data from the principal published studies describing the use of terpenes and their biological applications as antifungals.

Miopatía miotubular ligada al cromosoma X: informe clínico y revisión del fenotipo leve / X-linked myotubular myopathy: a clinical report and a review of the mild phenotype

Introducción: La miopatía miotubular ligada al X es una miopatía centronuclear rara que afecta aproximadamente a 1 de cada 50.000 recién nacidos varones causada por variantes patógenas en el gen de la miotubularina 1 (MTM1). La gravedad clínica varía; sin embargo, la necesidad de soporte ventilatorio ocurre casi invariablemente. Caso clínico: Presentamos el caso de un niño de 4 años que presentaba hipotonía muscular leve a los 12 meses, trastorno del lenguaje expresivo, retraso global del desarrollo y trastorno del procesamiento sensorial. La secuenciación clínica del exoma identificó la variante hemicigótica c.722G>A p.(Arg241His) en el exón 9 del gen de la miotubularina 1 (NM_000252.2). La madre es portadora heterocigota de la misma variante. Se estableció el diagnóstico de una forma leve de miopatía miotubular ligada al cromosoma X de herencia materna. El niño presentó una mejoría significativa con terapias del habla, ocupacional y física, sin intercurrencias respiratorias ni dependencia de ventilador. Conclusión: La presentación de una forma leve de esta miopatía miotubular, al notificarse más raramente, añadió desafío al diagnóstico. La combinación de hipotonía leve, dificultades de alimentación y trastorno del lenguaje expresivo debe hacer sospechar una enfermedad neuromuscular. Se carece de puntuaciones motoras o de desarrollo verificadas específicas de esta miopatía para determinar el pronóstico y la necesidad de otras terapias. Aunque actualmente la gravedad de la miopatía miotubular se clasifica según la dependencia del ventilador, esto puede ser insuficiente e inaplicable a los casos más leves. Es evidente la necesidad de un sistema de clasificación para los casos leves y moderados que evalúe la debilidad muscular y la fatiga, las limitaciones de la vida diaria, el retraso del desarrollo motor, las puntuaciones fenotípicas tempranas o las infecciones respiratorias recurrentes.(AU)

Introduction: X-linked myotubular myopathy is a rare centronuclear myopathy that affects approximately 1 in 50,000 male newborns caused by pathogenic variants in the myotubularin 1 gene (MTM1). The clinical severity varies, however the need for ventilatory support occurs almost invariably. Case report: We report the case of a 4-year-old boy presenting mild muscle hypotonia at 12 months-old, expressive language disorder, global developmental delay, and a sensory processing disorder. Clinical exome sequencing identified the hemizygous variant c.722G>A p.(Arg241His) in exon 9 of the myotubularin 1 gene (NM_000252.2). The mother is a heterozygous carrier of the same variant. A diagnosis of a mild form of maternal inherited X-linked myotubular myopathy was established. The child presented significant improvement with speech, occupational, and physical therapies, with no respiratory intercurrences or ventilator dependency. Conclusion: The presentation of a mild form of this myotubular myopathy, being less commonly reported, added challenge to the diagnosis. The combination of mild hypotonia, feeding difficulties and expressive language disorder should raise suspicion of a neuromuscular disease. There is a lack of verified motor or developmental scores specific to this myopathy to further determine prognosis and need of other therapies. While currently the severity myotubular myopathy is classified according to ventilator dependency, this may be insufficient and unapplicable to milder cases. There is an evident need for a grading system for mild and moderate cases assessing muscle weakness and fatigue, daily life limitations, motor developmental delay, early phenotypical scores, or recurrent respiratory infections.(AU)

RHOBTB2 p.Arg511Trp Mutation in Early Infantile Epileptic Encephalopathy-64: Review and Case Report.

Early infantile epileptic encephalopathy-64 (EIEE 64), also called RHOBTB2-related developmental and epileptic encephalopathy (DEE), is caused by heterozygous pathogenic variants (EIEE 64; MIM#618004) in the Rho-related BTB domain-containing protein 2 ( RHOBTB2 ) gene. To date, only 13 cases with RHOBTB2-related DEE have been reported. We add to the literature the 14th case of EIEE 64, identified by whole exome sequencing, caused by a heterozygous pathogenic variant in RHOBTB2 (c.1531C > T), p.Arg511Trp. This additional case supports the main features of RHOBTB2-related DEE: infantile-onset seizures, severe intellectual disability, impaired motor functions, postnatal microcephaly, recurrent status epilepticus, and hemiparesis after seizures.

X-linked myotubular myopathy: a clinical report and a review of the mild phenotype. / Miopatía miotubular ligada al cromosoma X: informe clínico y revisión del fenotipo leve.

INTRODUCTION: X-linked myotubular myopathy is a rare centronuclear myopathy that affects approximately 1 in 50,000 male newborns caused by pathogenic variants in the myotubularin 1 gene (MTM1). The clinical severity varies, however the need for ventilatory support occurs almost invariably. CASE REPORT: We report the case of a 4-year-old boy presenting mild muscle hypotonia at 12 months-old, expressive language disorder, global developmental delay, and a sensory processing disorder. Clinical exome sequencing identified the hemizygous variant c.722G>A p.(Arg241His) in exon 9 of the myotubularin 1 gene (NM_000252.2). The mother is a heterozygous carrier of the same variant. A diagnosis of a mild form of maternal inherited X-linked myotubular myopathy was established. The child presented significant improvement with speech, occupational, and physical therapies, with no respiratory intercurrences or ventilator dependency. CONCLUSION: The presentation of a mild form of this myotubular myopathy, being less commonly reported, added challenge to the diagnosis. The combination of mild hypotonia, feeding difficulties and expressive language disorder should raise suspicion of a neuromuscular disease. There is a lack of verified motor or developmental scores specific to this myopathy to further determine prognosis and need of other therapies. While currently the severity myotubular myopathy is classified according to ventilator dependency, this may be insufficient and unapplicable to milder cases. There is an evident need for a grading system for mild and moderate cases assessing muscle weakness and fatigue, daily life limitations, motor developmental delay, early phenotypical scores, or recurrent respiratory infections.

TITLE: Miopatía miotubular ligada al cromosoma X: informe clínico y revisión del fenotipo leve.Introducción. La miopatía miotubular ligada al X es una miopatía centronuclear rara que afecta aproximadamente a 1 de cada 50.000 recién nacidos varones causada por variantes patógenas en el gen de la miotubularina 1 (MTM1). La gravedad clínica varía; sin embargo, la necesidad de soporte ventilatorio ocurre casi invariablemente. Caso clínico. Presentamos el caso de un niño de 4 años que presentaba hipotonía muscular leve a los 12 meses, trastorno del lenguaje expresivo, retraso global del desarrollo y trastorno del procesamiento sensorial. La secuenciación clínica del exoma identificó la variante hemicigótica c.722G>A p.(Arg241His) en el exón 9 del gen de la miotubularina 1 (NM_000252.2). La madre es portadora heterocigota de la misma variante. Se estableció el diagnóstico de una forma leve de miopatía miotubular ligada al cromosoma X de herencia materna. El niño presentó una mejoría significativa con terapias del habla, ocupacional y física, sin intercurrencias respiratorias ni dependencia de ventilador. Conclusión. La presentación de una forma leve de esta miopatía miotubular, al notificarse más raramente, añadió desafío al diagnóstico. La combinación de hipotonía leve, dificultades de alimentación y trastorno del lenguaje expresivo debe hacer sospechar una enfermedad neuromuscular. Se carece de puntuaciones motoras o de desarrollo verificadas específicas de esta miopatía para determinar el pronóstico y la necesidad de otras terapias. Aunque actualmente la gravedad de la miopatía miotubular se clasifica según la dependencia del ventilador, esto puede ser insuficiente e inaplicable a los casos más leves. Es evidente la necesidad de un sistema de clasificación para los casos leves y moderados que evalúe la debilidad muscular y la fatiga, las limitaciones de la vida diaria, el retraso del desarrollo motor, las puntuaciones fenotípicas tempranas o las infecciones respiratorias recurrentes.

A model for preservation of thymocyte-depleted thymus

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

Stress Hormone Corticosterone Controls Metabolic Mitochondrial Performance and Inflammatory Signaling of In Vitro Cultured Sertoli Cells.

Stress, as a physiological response, is a major factor that affects several processes, including reproductive functions. The main hormonal players of stress are cortisol (humans) and corticosterone (rodents). Sertoli cells (SCs), as key contributors for the testicular homeostasis maintenance, are extensively challenged by different hormones, with glucocorticoid corticosterone being the signaling modulator that may impact these cells at different levels. We aimed to characterize how corticosterone modulates SCs energy balance, putting the mitochondrial performance and signaling output in perspective as the cells can disperse to the surroundings. TM4 mouse SCs were cultured in the absence and presence of corticosterone (in nM: 20, 200, and 2000). Cells were assessed for extracellular metabolic fluxes, mitochondrial performance (cell respirometry, mitochondrial potential, and mitochondrial complex expressions and activities), and the expression of androgen and corticosteroid receptors, as well as interleukine-6 (IL-6) and glutathione content. Corticosterone presented a biphasic impact on the extracellular fluxes of metabolites. Low sub-physiological corticosterone stimulated the glycolytic activity of SCs. Still, no alterations were perceived for lactate and alanine production. However, the lactate/alanine ratio was decreased in a dose-dependent mode, opposite to the mitochondrial complex II activity rise and concurrent with the decrease of IL-6 expression levels. Our results suggest that corticosterone finely tuned the energetic profile of mouse SCs, with sub-physiological concentrations promoting glycolytic expenditure, without translating into cell redox power and mitochondrial respiratory chain performance. Corticosterone deeply impacted the expression of the pro-inflammatory IL-6, which may alter cell-to-cell communication in the testis, in the last instance and impact of the spermatogenic performance.

Síndrome PURA en una niña con retraso grave del desarrollo: un diagnóstico desafiante / PURA syndrome in a child with severe developmental delay: a challenging diagnosis

Introducción: El síndrome PURA es una condición autosómica dominante poco común causada por variantes patogénicas de novo en el gen PURA y que se caracteriza por un fenotipo multisistémico que incluye retraso del neurodesarrollo global, hipotonía temprana, ausencia de habla, dificultades para alimentarse, hipersomnolencia, epilepsia y trastornos del movimiento. Caso clínico: Presentamos una niña de 9 años con hipotonía y dificultades para alimentarse con retraso del crecimiento desde el período neonatal. A la edad de 3 años era evidente el retraso motor e intelectual, tenía una marcha de base amplia, no hablaba y una respuesta de sobresalto acústico exagerada. Desarrolló estereotipias de mano-boca y epilepsia a los 6 años. La monitorización electroencefalográfica continua de 24 horas reveló una actividad lenta global y una actividad epileptiforme frecuente en las áreas temporal izquierda y centrotemporal. La resonancia magnética del cerebro reveló un retraso en la mielinización. A los 6 años, la secuenciación clínica del exoma identificó una variante patógena heterocigótica en el gen PURA, c.153delA p. (Leu54CysfsTer24). Conclusión: El síndrome PURA tiene características clínicas similares a otros trastornos neurológicos, pero la asociación con algunas características clínicas, no tan comunes en otras entidades neurológicas, como no poder hablar, pero poder seguir órdenes simples, y una respuesta de sobresalto acústico exagerado, deben ser factores de sospecha de síndrome PURA y servir para realizar un análisis genético para confirmar el diagnóstico y proporcionar una intervención multidisciplinar precoz.(AU)

Introduction: PURA syndrome is a rare autosomal dominant condition caused by de novo pathogenic variants in PURA gene and characterized by a multisystemic phenotype that includes global neurodevelopmental delay, early hypotonia, absence of speech, feeding difficulties, hypersomnolence, epilepsy and movement disorders. Case report: We report a 9-year-old girl with hypotonia and feeding difficulties with failure to thrive since the neonatal period. At the age of 3 years motor and intellectual delay were evident, she had a wide-based gait, no speech and an exaggerated acoustic startle response. She developed hand-mouthing stereotypies and epilepsy at 6 years old. The 24 hours continuous electroencephalogram monitoring revealed global slow activity and frequent epileptiform activity in left temporal and centrotemporal areas. The brain MRI revealed delayed myelination. At 6 years old the clinical exome sequencing identified a heterozygous pathogenic variant in the PURA gene, c.153delA p.(Leu54CysfsTer24). Conclusion: PURA syndrome has clinical features similar to other neurological disorders but the association with some clinical features, not as common in other neurological entities, like never being able to speak but being able to follow simple orders and exaggerated acoustic startle response, should raise the suspicion of PURA syndrome and genetic analysis must be performed to confirm the diagnosis and provide early multidisciplinary intervention.(AU)

PURA syndrome in a child with severe developmental delay: a challenging diagnosis. / Síndrome PURA en una niña con retraso grave del desarrollo: un diagnóstico desafiante.

INTRODUCTION: PURA syndrome is a rare autosomal dominant condition caused by de novo pathogenic variants in PURA gene and characterized by a multisystemic phenotype that includes global neurodevelopmental delay, early hypotonia, absence of speech, feeding difficulties, hypersomnolence, epilepsy and movement disorders. CASE REPORT: We report a 9-year-old girl with hypotonia and feeding difficulties with failure to thrive since the neonatal period. At the age of 3 years motor and intellectual delay were evident, she had a wide-based gait, no speech and an exaggerated acoustic startle response. She developed hand-mouthing stereotypies and epilepsy at 6 years old. The 24 hours continuous electroencephalogram monitoring revealed global slow activity and frequent epileptiform activity in left temporal and centrotemporal areas. The brain MRI revealed delayed myelination. At 6 years old the clinical exome sequencing identified a heterozygous pathogenic variant in the PURA gene, c.153delA p.(Leu54CysfsTer24). CONCLUSION: PURA syndrome has clinical features similar to other neurological disorders but the association with some clinical features, not as common in other neurological entities, like never being able to speak but being able to follow simple orders and exaggerated acoustic startle response, should raise the suspicion of PURA syndrome and genetic analysis must be performed to confirm the diagnosis and provide early multidisciplinary intervention.

TITLE: Síndrome PURA en una niña con retraso grave del desarrollo: un diagnóstico desafiante.Introducción. El síndrome PURA es una condición autosómica dominante poco común causada por variantes patogénicas de novo en el gen PURA y que se caracteriza por un fenotipo multisistémico que incluye retraso del neurodesarrollo global, hipotonía temprana, ausencia de habla, dificultades para alimentarse, hipersomnolencia, epilepsia y trastornos del movimiento. Caso clínico. Presentamos una niña de 9 años con hipotonía y dificultades para alimentarse con retraso del crecimiento desde el período neonatal. A la edad de 3 años era evidente el retraso motor e intelectual, tenía una marcha de base amplia, no hablaba y una respuesta de sobresalto acústico exagerada. Desarrolló estereotipias de mano-boca y epilepsia a los 6 años. La monitorización electroencefalográfica continua de 24 horas reveló una actividad lenta global y una actividad epileptiforme frecuente en las áreas temporal izquierda y centrotemporal. La resonancia magnética del cerebro reveló un retraso en la mielinización. A los 6 años, la secuenciación clínica del exoma identificó una variante patógena heterocigótica en el gen PURA, c.153delA p. (Leu54CysfsTer24). Conclusión. El síndrome PURA tiene características clínicas similares a otros trastornos neurológicos, pero la asociación con algunas características clínicas, no tan comunes en otras entidades neurológicas, como no poder hablar, pero poder seguir órdenes simples, y una respuesta de sobresalto acústico exagerado, deben ser factores de sospecha de síndrome PURA y servir para realizar un análisis genético para confirmar el diagnóstico y proporcionar una intervención multidisciplinar precoz.

Degradation of diclofenac in water under LED irradiation using combined g-C3N4/NH2-MIL-125 photocatalysts.

This study reports the photocatalytic degradation of diclofenac by hybrid materials prepared by combination of graphitic carbon nitride (g-C3N4) and titanium-metal organic framework (NH2-MIL-125), in different mass proportions (MOF:C3N4 of 25:75, 50:50 and 75:25). The hybrid materials were fully characterized, and their properties compared to those of the individual components, whose presence was confirmed by XRD. The porous structure was the result of the highly microporous character of the MOF and the non-porous one of g-C3N4. The band gap values were very close to that of MOF component. Photoluminescence measurements suggested an increase on the recombination rate associated to the presence of g-C3N4. Photodegradation tests of diclofenac (10 mg·L-1) were performed under UV LED irradiation at 384 nm. The hybrid materials showed higher photocatalytic activity than the individual components, suggesting the occurrence of some synergistic effect. The photocatalyst with a MOF:g-C3N4 ratio of 50:50 yielded the highest conversion rate, allowing complete disappearance of diclofenac in 2 h. Experiments with scavengers showed that superoxide radicals and holes played a major role in the photocatalytic process photodegradation, being that of hydroxyl radicals less significant. From the identification of by-products species, a degradation pathway was proposed for the degradation of diclofenac under the experimental operating conditions.

The incidence of severe oral mucositis and its occurrence sites in pediatric oncologic patients.

BACKGROUND: Childhood cancer is one of the main causes of child mortality and its treatment has debilitating effects on the oral cavity. Several oral mucositis (SOM) is one of the most common and may cause undesirable symptoms such as pain and risk of systemic infection. MATERIAL AND METHODS: This was a longitudinal, retrospective, and observational study determining the incidence of severe oral mucositis (SOM) and its occurrence sites in pediatric oncologic patients, in João Pessoa, Brazil, between 2013 and 2018. Data from 56 patients aged 1 to 18 years were collected from their medical records and through an oral mucosa examination, from the 1st to 5th week of chemotherapy treatment (CT) using the modified Oral Assessment Guide, by previously calibrated examiners (Kappa index > 0.7). The data were analyzed by the Chi-square test, and Odds Ratios were calculated. RESULTS: Most patients were females (54.5%), aged 8.8 years (± 4.8), with hematologic tumors (73.2%), predominantly Acute Lymphoid Leukemia (50.0%). An increase in the occurrence of SOM was observed throughout the CT (P = 0.05), ranging from 12.5% in the 1st to 35.7% in the 5th CT week. In the 1st CT week, there was a predominance of alterations in the lips (5.5%) and saliva (5.5%), while in the 5th, the jugal / palate mucosa (21.4%) remained the most affected site by SOM. Differences in the severity of SOM in the jugal / palate mucosa (P = 0.01) and labial mucosa (P = 0.04) were observed over time. In the 5th CT week, the likelihood of developing SOM was 13.3-fold higher (95% CI: 1.5 - 105.6) in patients with hematologic tumors. CONCLUSIONS: The incidence of SOM was higher in the 5th CT week, most commonly affecting the jugal / palate mucosa, and patients with hematologic tumors were more prone to develop SOM.

[Persistent respiratory distress or something else?] / ¿Distrés respiratorio persistente o algo más?

TITLE: ¿Distrés respiratorio persistente o algo más?

Plant Silicon Amendment Does Not Reduce Population Growth of Schizaphis graminum or Host Quality for the Parasitoid Lysiphlebus testaceipes.

Interactions between different pest control methods can affect Integrated Pest Management efficiency. This study sought to evaluate (1) if Si accumulation is related to the level of constitutive resistance in sorghum genotypes, (2) the level of Si induces resistance by antibiosis in sorghum genotypes with different levels of constitutive resistance to Schizaphis graminum (Rondani) (reared individualized or in colonies), and (3) the fitness of Lysiphlebus testaceipes (Cresson) in aphids reared on Si-treated and untreated plants. Several experiments were conducted under greenhouse conditions, using sorghum genotypes with different levels of resistance grown in pots with or without the addition of Si to the soil. The susceptible (BR007B), moderately resistant (GB3B), and highly resistant (TX430XGR111) genotypes all absorbed more Si when it was added to the soil compared with when it was not amended. However, the final Si content of treated plants was not related to the level of constitutive resistance among treated genotypes. While Si soil application did reduce the fecundity of individualized aphids reared on the susceptible and moderately resistant sorghum plants, it did not reduce populational growth of aphid colonies, independent of the level of plant's constitutive resistance. Parasitoid (L. testaceipes) had higher weight when reared from aphids fed on plants with added Si. Sorghum × constitutive resistance × S. graminum interactions were affected by plant Si content only for individualized aphids but not for aphid colonies. Sorghum × S. graminum × L. testaceipes interactions suggest that Si can have, overall, a positive effect on the biological control of S. graminum.

Modeling Overdispersion, Autocorrelation, and Zero-Inflated Count Data Via Generalized Additive Models and Bayesian Statistics in an Aphid Population Study.

Count variables are often positively skewed and may include many zero observations, requiring specific statistical approaches. Interpreting abiotic factor changes in insect populations of crop pests, under this condition, can be difficult. The analysis becomes even more complicated because of possible temporal or spatial correlation, irregularly spaced data, heterogeneity over time, and zero inflation. Generalized additive models (GAM) are important tools to evaluate abiotic factors. Moreover, Markov chain Monte Carlo (MCMC) techniques can be used to fit a model that contains a temporal correlation structure, based on Bayesian statistics (BGAM). We compared methods of modeling the effects of temperature, precipitation, and time for the Brevicoryne brassicae (L.) population in Uberlândia, Brasil. We applied the proposed BGAM to the data, comparing this to the GAM model with and without autocorrelation for time, using the statistical programming language R. Analysis of deviance identified significant effects of the smoothers for precipitation and time on the frequentist models. With BGAM, the problem in variance estimations for precipitation and temperature from the previous models was solved. Furthermore, trace and density plots for population-level effects for all parameters converged well. The estimated smoothing curves showed a linear effect with an increase of precipitation, where lower precipitation indicated no presence of the aphid. The average temperature did not affect the aphid incidence. Autocorrelation was solved with ARMA structures, and the excess of zero was solved with zero-inflation models. The example of B. brassicae incidence showed how well abiotic (and biotic) factors can be modeled and analyzed using BGAM.

Taxonomic Status and Population Oscillations of Aphidius colemani Species Group (Hymenoptera: Braconidae) in Southern Brazil.

Aphidius colemani (Viereck) was reported in Brazil before the Biological Control Program of Wheat Aphids (BCPWA) when Mediterranean genotypes were introduced from France and Israel. This species was re-described as a complex called A. colemani group composed of three species. Consequently, uncertainty remains about which parasitoid of the group is occurring in southern Brazil. This study has two main objectives: (i) re-examine the species status of A. colemani group collected during the introduction of parasitoids and from a 10-year (2009-2018) monitoring program in wheat fields in northern Rio Grande do Sul (RS), Brazil; (ii) describe the variation in the population density of parasitoids and its association with meteorological factors during this period. We examined 116 specimens from the Embrapa Wheat entomological collection, and those collected in Moericke traps in Coxilha, RS. All the parasitoids of the A. colemani group from the BCPWA period were identified as Aphidius platensis (Brèthes). In traps, 6541 cereal aphid parasitoids were collected, of which 61.9% (n = 4047) were from A. colemani group and all those were identified as A. platensis. Temperature was the factor that effected population density with the highest number of parasitoids recorded in the winter months. Sex ratio changed between years varying from 0.50 to 0.97. The parasitoid A. platensis was the only species in the A. colemani group sampled during 10 years of monitoring.

T cell receptor excision circles as a tool for evaluating thymic function in young children.

The thymus is a primary lymphoid organ responsible for the maturation of T cells as well as the immunological central tolerance. It is in the antenatal period and infancy that it plays its major role. In clinical practice, T cell receptor excision circles (TRECs) are considered a direct and reliable measure of the thymic function. TRECs are a by-product of DNA formation in gene rearrangement of T cell receptors. They are stable and they do not duplicate during mitosis, representing the recent emigrant T cells from the thymus. Despite their importance, TRECs have been neglected by physicians and there is a lack of data regarding thymic function during infancy of healthy children. In order to evaluate thymic function in the first years of life, we propose measuring TRECs as a valuable tool. One hundred and three blood samples from children and adolescents between 3 months and 20 years of age were analyzed. The mean TRECs count was 136.77±96.7 copies of TRECs/µL of DNA. The individuals between 0 and 5 years of age had significantly higher TRECs values than those between 10 and 20 years of age. No significant difference was observed in TRECs values among age groups below 5 years of age. An inverse correlation between TRECs and age was found (r=0.3 P=0.003). These data highlight and validate the evidence of decreased thymus function with age, even during infancy. Awareness should be raised with this important albeit ignored organ.

Host Preference and Fitness of Lysiphlebus testaceipes (Hymenoptera: Braconidae) in Different Instars of the Aphid Schizaphis graminum.

Parasitoid fitness is strongly influenced by host quality for immature parasitoid development and by oviposition host choice patterns made by adult female parasitoids. This study aimed to determine immature host quality of Schizaphis graminum (Rondani) (Hemiptera: Aphididae) and Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae) host instars preference. To this end, the host quality of immature stages of S. graminum was assessed by rearing the parasitoid in all four instars of the aphid, placing each nymph stage of the aphid parasitized by L. testaceipes in separate Petri dishes with sorghum leaves over a 1% agar-water solution at 23 ± 1°C and a 12:12 h L:D photoperiod. The host-age preferences of the parasitoid between second and fourth instar nymphs were analyzed by choice (ten nymphs of each instar) and non-choice (ten nymphs of one instar) tests, observing parasitoid foraging in a 5-cm arena for 5 min under a stereoscopic microscope. Third and fourth instars were better hosts than first or second instars, with faster developmental times, resulting in larger wasps with bigger hind tibia size and more eggs in their ovarioles (i.e., higher initial egg load). Females preferred to oviposit in fourth instar aphids in both choice and non-choice tests. Selection by adult L. testaceipes females of older instars of S. graminum for oviposition maximizes parasitoid fitness as these instars are intrinsically more suitable for development of parasitoid offspring.