Seroprevalence of sporotrichosis infection in cats living in the Buenos Aires epizootic area.

This study aimed to perform a seroepidemiological survey on the prevalence of sporotrichosis among cats living in the Northern area of Buenos Aires, where a four-fold increase of Sporothrix brasiliensis infections were diagnosed during the last decade. For this purpose, an in-house indirect ELISA test sensitized with S. brasiliensis crude antigens was used. The ELISA test showed 100.0% sensitivity and 95.0% specificity. Antibodies against S. brasiliensis antigens were detected in 3.7% (9/241) of healthy cats evaluated, suggesting likely exposure or infection to this fungus. This ELISA test would be a valuable screening tool for diagnosing sporotrichosis and for seroepidemiological surveys.

S. brasiliensis is the primary cause of feline sporotrichosis in Argentina. The seroprevalence of sporotrichosis infection in urban localities of Buenos Aires province is reported for the first time. An ELISA test using S. brasiliensis crude antigens is also described.

First characterization of a canine parvovirus causing fatal disease in coatis (Nasua nasua).

A canine parvovirus (CPV)-like virus was detected by PCR and isolated from dead coatis in Argentina. Analysis of the full-length genome sequence revealed that it resembled CPV-but also contained a mutation in the VP2 protein (Arg377Ser) that has not been described previously. This is the first report of a CPV-like virus producing clinical disease in coatis. Genetic similarity to CPV-2c viruses detected in Brazil suggests a strong relationship between these viruses. Although the pathogenic potential of CPV- and feline panleukopenia virus (FPV)-like strains in wild animals is still not completely understood, this study highlights the importance of parvoviruses as a threat to wildlife if proper conditions are present.

Criterios diagnósticos para la infección por el virus de la inmunodeficiencia felina y el virus de la leucemia felina en gatos domésticos de Buenos Aires, Argentina / Viral diagnostic criteria for Feline immunodeficiency virus and Feline leukemia virus infections in domestic cats from Buenos Aires, Argentina

A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access.

Para determinar la prevalencia en la ciudad de Buenos Aires del virus de la inmunodeficiencia felina (FIV) y del virus de la leucemia felina (FeLV), y analizar los factores de riesgo que pudieran estar asociados a ellos, se realizó un estudio transversal en gatos atendidos en el Hospital de Pequeños Animales de la Facultad de Ciencias Veterinarias de la Universidad de Buenos Aires. Se analizaron por serología (inmunocromatografía --#91;IA--#93;) y por hemi-nested PCR (n-PCR) 255 muestras de sangre de gatos con síntomas compatibles con infección por FIV o FeLV. La IA y la n-PCR revelaron porcentajes similares de animales positivos para FIV, mientras que para FeLV el diagnóstico por n-PCR resultó más sensible. Se discuten las diferencias halladas entre los métodos diagnósticos y su elección según la edad del animal. Las historias clínicas de 90 de los 255 gatos mostraron perfiles sanguíneos similares a otros ya reportados y revelaron el mayor riesgo de infección con ambos virus en machos adultos con acceso al exterior.

Viral diagnostic criteria for Feline immunodeficiency virus and Feline leukemia virus infections in domestic cats from Buenos Aires, Argentina.

A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access.

Old Things New View: Ascorbic Acid Protects the Brain in Neurodegenerative Disorders.

Ascorbic acid is a key antioxidant of the Central Nervous System (CNS). Under brain activity, ascorbic acid is released from glial reservoirs to the synaptic cleft, where it is taken up by neurons. In neurons, ascorbic acid scavenges reactive oxygen species (ROS) generated during synaptic activity and neuronal metabolism where it is then oxidized to dehydroascorbic acid and released into the extracellular space, where it can be recycled by astrocytes. Other intrinsic properties of ascorbic acid, beyond acting as an antioxidant, are important in its role as a key molecule of the CNS. Ascorbic acid can switch neuronal metabolism from glucose consumption to uptake and use of lactate as a metabolic substrate to sustain synaptic activity. Multiple evidence links oxidative stress with neurodegeneration, positioning redox imbalance and ROS as a cause of neurodegeneration. In this review, we focus on ascorbic acid homeostasis, its functions, how it is used by neurons and recycled to ensure antioxidant supply during synaptic activity and how this antioxidant is dysregulated in neurodegenerative disorders.

Cavß2 transcription start site variants modulate calcium handling in newborn rat cardiomyocytes.

In the heart, the main pathway for calcium influx is mediated by L-type calcium channels, a multi-subunit complex composed of the pore-forming subunit CaV1.2 and the auxiliary subunits CaVα2δ1 and CaVß2. To date, five distinct CaVß2 transcriptional start site (TSS) variants (CaVß2a-e) varying only in the composition and length of the N-terminal domain have been described, each of them granting distinct biophysical properties to the L-type current. However, the physiological role of these variants in Ca(2+) handling in the native tissue has not been explored. Our results show that four of these variants are present in neonatal rat cardiomyocytes. The contribution of those CaVß2 TSS variants on endogenous L-type current and Ca(2+) handling was explored by adenoviral-mediated overexpression of each CaVß2 variant in cultured newborn rat cardiomyocytes. As expected, all CaVß2 TSS variants increased L-type current density and produced distinctive changes on L-type calcium channel (LTCC) current activation and inactivation kinetics. The characteristics of the induced calcium transients were dependent on the TSS variant overexpressed. Moreover, the amplitude of the calcium transients varied depending on the subunit involved, being higher in cardiomyocytes transduced with CaVß2a and smaller in CaVß2d. Interestingly, the contribution of Ca(2+) influx and Ca(2+) release on total calcium transients, as well as the sarcoplasmic calcium content, was found to be TSS-variant-dependent. Remarkably, determination of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) messenger RNA (mRNA) abundance and cell size change indicates that CaVß2 TSS variants modulate the cardiomyocyte hypertrophic state. In summary, we demonstrate that expression of individual CaVß2 TSS variants regulates calcium handling in cardiomyocytes and, consequently, has significant repercussion in the development of hypertrophy.

Reproducción Estacional en el Macho / Seasonal Reproduction in the Male

Hay una sorprendente relación entre el ambiente y adaptaciones de la conducta reproductiva, muy evidente en los reproductores estacionales que pueden reproducirse en días cortos o largos, de acuerdo a factores proximales, especialmente el fotoperiodo luminoso que provoca cambios fotoneuroendocrinos. Estos, involucran fotoreceptores, un reloj biológico y el aparato neuroendocrino. Las gonadotrofinas (GT), el desarrollo gonadal, la retroalimentación negativa de las GT por los esteroides sexuales, la intervención de las fibras retino-hipotalámico y los núcleos supraquiasmáticos así como la secreción de melatonina, intervienen en esta regulación. El pulso generador del hipotálamo (eminencia media) es importante en el control de la adenohipófisis respecto de la secreción de LH y FSH. En el testículo, las endocrinocitos intersticiales (de Leydig) (que secretan testosterona y también estrógenos), establecen un asa de retroalimentación con la adenohipófisis y el hipotálamo en un circuito de asa larga, corta y ultracorta, donde neuronas neuroendocrinas tienen un rol importante. Los sustentocitos (células de Sertoli) (intratubulares) son importantes por su rol mecánico, trófico y metabólico respecto a las células germinales y la secreción de activina e inhibina, que provoca o inhibe la secreción de FSH respectivamente. Los sustentocitos también secretan muchas proteínas específicas entre las cuales se encuentra la proteína que liga andrógenos (ABP), importante porque concentra 100 veces la testosterona en el parénquima testicular. La secreción tónica, por pulsos de GT, especialmente LH, es debida a actividad hipotalámica a través del control de generación de estos pulsos que se inicia en la pubertad. La reproducción en el potro y el toro se presentan como ejemplos.

There is a surprising interrelationship between environments and adaptation of reproductive behaviour, very evident in seasonal breeders; which may reproduce in long or short days, according to proximal factors, mainly the light photoperiod which triggers photoneuroendocrine changes. These involve photoreceptors, a clock and the neuroendocrine apparatus. Gonadotropins (GT), gonadal development, negative feed back of GT done by sexual steroid, the intervention of the retino-hypothalamic fibers, and suprachiasmatics nucleus as well as melatonine secretion, intervene in this regulation. Of importance is the pulse generator of the hypothalamus (medial eminence) and its control of adenohypofisis for the secretion of LH and FSH. In the testis interstitial endocrine cells (Leydig)(secreting testosterone and also estrogens), establish a feed back loop with the adenohypofisis and hypothalamus in a circuit of long, short and ultra short circuit with neuroendocrine neurons playing a key role. Sustentocyte intratubular (Sertoli)are also important for their trophic, mechanic and metabolic relationships with the germ cells, and the secretions of activine and inhibine, which triggers or inhibits FSH secretions respectively. Sustentocyte also secrete many specifics proteins among which ABP (Androgen Binding Protein) is important because it concentrates 100 fold testosterone in the testicular parenchyme. Tonic secretion by pulses of GT, mainly LH, is due to hypothalamic activity with the control generation of these pulses by puberty. Reproduction in the stallion and the bull are presented as examples.

Rat spermatogenesis damage in intermittent hypobaric hypoxia and the protective role of melatonin. II: testicular parameters / Daño de la espermatogénesis en rata en la hipoxia hipobárica intermitente y rol protector de la melatonina. II: parámetros testiculares

At present it is not clear if male fertility is affected by intermittent hypobaric hypoxia (IHH). This is an important issue since a large human population works over 3000 masl. This study analyzes testicular changes in adult Sprague Dawley rats after five cycles of IHH (7 day exposure to 4200 masl in a hypobaric chamber / 7 day at 500 masl). The animals were separated into groups of 8, one group was exposed to hypoxia (7 days), and the others to IHH for one to five cycles. Controls (500 masl) were examined at the beginning and at the end of the 70 experimental days. A duplicate set of rats treated with melatonin (supposedly protecting from hypoxia) was also examined, as were their controls, injected with 0,03 percent ethanol (melatonin solvent).Immunohistochemical and histometric analysis of testicular tissue were performed. Damage caused by IHH increases with time. Morphometry reveals an increase in tubular and luminal diameters and a reduction in epithelial height. Inmunohistochemistry for HIF-1alpha shows an increase with time, however the opposite happens with HSP-70. Spermatogenic cells submitted to comet assay present an increase of (+) cells. Melatonin counteracts all this damage, possibly due to its high efficiency as a reactive oxygen species scavenger. In conclusion, IHH exposure damages male reproductive function.

Actualmente no se conoce claramente si la fertilidad masculina se afecta por la hipoxia hipobarica intermitente (IHH). Esto es de importancia porque una gran población humana trabaja sobre 3000 metros sobre el nivel del mar (sml). Este trabajo analiza los cambios testiculares en ratas adultas Sprague Dawley luego de cinco ciclos de IHH (7 días a 4.200 sml) en una camara hipobarica/7días a 500 metros: Normoxia). Los animales de dividieron en grupos de 8; un grupo expuesto a hipoxia (7 días ) y los otros a IHH por uno y hasta cinco ciclos. Los controles ( 500 sml) se analizaron al inicio y al final de los 70 días experimentales. Un set duplicado de ratas tratadas con melatonina (considerada protectora de la Hipoxia) se examinó también, así como sus controles, inyectados con etanol 0,03 por ciento (solvente de la melatonina).Se realizó análisis histométrico e inmunohistoquímico del tejido testicular. El daño causado por IHH aumenta con el tiempo. La morfometría reveló un aumento de los diámetros del túbulo y lumen y una reducción de la altura del epitelio. La inmunohistoquímica de HIF-1 alpha muestra aumento del número de túbulos positivos con el tiempo aunque lo opuesto ocurre para HSP-70. El ensayo de cometa muestra un aumento del número de células espermátogénicas (+). La melatonina controla este daño, posiblemente debido a asu alta eficiencia como neutralizador de especies reactivas del oxígeno. En conclusión, la exposición a IHH daña la función reproductiva masculina.

Lack of antibody affinity maturation due to poor Toll-like receptor stimulation leads to enhanced respiratory syncytial virus disease.

Respiratory syncytial virus (RSV) is a leading cause of hospitalization in infants. A formalin-inactivated RSV vaccine was used to immunize children and elicited nonprotective, pathogenic antibody. Immunized infants experienced increased morbidity after subsequent RSV exposure. No vaccine has been licensed since that time. A widely accepted hypothesis attributed the vaccine failure to formalin disruption of protective antigens. Here we show that the lack of protection was not due to alterations caused by formalin but instead to low antibody avidity for protective epitopes. Lack of antibody affinity maturation followed poor Toll-like receptor (TLR) stimulation. This study explains why the inactivated RSV vaccine did not protect the children and consequently led to severe disease, hampering vaccine development for 42 years. It also suggests that inactivated RSV vaccines may be rendered safe and effective by inclusion of TLR agonists in their formulation, and it identifies affinity maturation as a key factor for the safe immunization of infants.