Draft genomes of 16 Bartonella henselae strains from cats in Valdivia, Chile.

Bartonella henselae is a primary zoonotic agent, having cats as asymptomatic reservoirs. In humans, it causes cat scratch disease. Here, we report the whole genome sequences of 16 strains isolated from cats in Valdivia city, Southern Chile. Strains showed little variability in the multilocus sequence typing profiles.

Prevalence, Onset, Evolution, and Prediction of Spasticity Poststroke: A Longitudinal Study / Prevalencia, inicio, evolución y predicción de la espasticidad posterior a un ACV: un estudio longitudinal / Prevalência, início, evolução e previsão de espasticidade após AVC: um estudo longitudinal

Introduction: Because of the the complex physiopathology of spasticity, it is distinguished as one of the most significant positive clinical signs of upper motor neuron syndrome, constituting a clinical feature that has great impact in the neurorehabilitation setting. Thus, the current study aimed to determine the prevalence, onset, evolution, and prediction of spasticity after a stroke. Materials and Methods: A correlational, longitudinal design was used. A total of 136 patients were evaluated at the following times: 10 days (T1), 3 months (T2), and 12 months (T3) poststroke. The initial evaluation included sociodemographic and clinical data (T1). Muscle tone was measured (T1, T2, and T3) using the Modified Ashworth Scale. Results: The prevalence of poststroke spasticity in the elbow was 37.5 % at T1 and 57.4 % at T2 and T3. Among patients with motor damage, the onset of spasticity occurred at T1 in 44.7 %, between T1 and T2 in 23.7 %, and between T2 and T3 in 0.9 %. Significant predictors of the alteration in muscular tone for at least two of the evaluation times were ethnic self-classification, type, area, extent of stroke, and number of sessions. Conclusions: Spasticity onset occurs during the first 10 days after a stroke. More clinical than sociodemographic variables predicted spasticity.

Introducción: la espasticidad se destaca como uno de los signos clínicos positivos más significativos del síndrome de motoneurona superior, por su compleja fisiopatología, y constituye una característica clí- nica de gran impacto en el ámbito de la neurorrehabilitación. Por lo tanto, el objetivo fue determinar la prevalencia, el inicio, la evolución y la predicción de la espasticidad después de un accidente cerebro- vascular. Materiales y métodos: se utilizó un diseño longitudinal correlacional. Se evaluaron 136 pacientes: 10 días (T1), 3 meses (T2) y 12 meses (T3) pos-ACV. La evaluación incluyó datos sociodemográficos y clínicos (T1) y se midió el tono muscular (T1, T2 y T3) mediante la Escala de Ashworth Modificada. Resultados: la prevalencia en el codo fue del 37.5 % en T1, y del 57.4 % en T2 y T3. Entre los pacientes con daño motor, el inicio de la espasticidad ocurrió en T1 para el 44.7 % de ellos, entre T1 y T2 para el 23.7 % y entre T2 y T3 para el 0.9 %. La autoclasificación étnica, el tipo, el área, la extensión del ictus y el número de sesiones predijeron significativamente la alteración del tono muscular en al menos dos ocasiones. Conclusiones: el inicio de la espasticidad ocurre durante los 10 primeros días después de un ACV. Más variables clínicas que sociodemográficas predijeron espasticidad.

Introdução: a espasticidade destaca-se como um dos sinais clínicos positivos mais significativos da síndrome do neurônio motor superior, devido à sua fisiopatologia complexa, e constitui uma característica clínica de grande impacto no campo da neurorreabilitação. Portanto, nosso objetivo foi determinar a prevalência, início, evolução e predição da espasticidade após o acidente vascular cerebral. Materiais e métodos: foi utilizado um desenho correlacional longitudinal. Foram avaliados 136 pacientes: 10 dias (T1), 3 meses (T2) e 12 meses (T3) pós-AVC. A avaliação incluiu dados sociodemográficos e clínicos (T1) e o tônus muscular (T1, T2 e T3) foi medido por meio da Escala Modificada de Ashworth. Resultados: a prevalência no cotovelo foi de 37,5 % em T1 e 57,4 % em T2 e T3. Entre os pacientes com prejuízo motor, o início da espasticidade ocorreu em T1 em 44,7 % deles, entre T1 e T2 em 23,7 % e entre T2 e T3 em 0,9 % dos pacientes. A autoclassificação étnica, o tipo, a área, a extensão do AVC e o número de sessões predisseram significativamente as anormalidades do tônus muscular em pelo menos duas ocasiões. Conclusões: o início da espasticidade ocorre durante os primeiros 10 dias após o acidente vascular cerebral. Mais variáveis clínicas do que sociodemográficas previram a espasticidade

Relationship between Hypoxic and Immune Pathways Activation in the Progression of Neuroinflammation: Role of HIF-1α and Th17 Cells.

Neuroinflammation is a common event in degenerative diseases of the central and peripheral nervous system, triggered by alterations in the immune system or inflammatory cascade. The pathophysiology of these disorders is multifactorial, whereby the therapy available has low clinical efficacy. This review propounds the relationship between the deregulation of T helper cells and hypoxia, mainly Th17 and HIF-1α molecular pathways, events that are involved in the occurrence of the neuroinflammation. The clinical expression of neuroinflammation is included in prevalent pathologies such as multiple sclerosis, Guillain-Barré syndrome, and Alzheimer's disease, among others. In addition, therapeutic targets are analyzed in relation to the pathways that induced neuroinflammation.

Distribución de patrones espásticos en extremidad superior posterior a un daño de motoneurona superior / Distribution of spastic patterns in upper extremity after an upper motor neuron syndrome

ANTECEDENTES: la evidencia sobre personas que presentan daño de motoneurona superior y desarrollan un patrón de espasticidad en extremidad superior (EES) es limitada. Este signo positivo de disfunción o secundario al daño de la motoneurona superior se asocia con pérdida de función y disminución de la independencia, provocando discapacidad y alterando la calidad de vida. OBJETIVO: determinar la distribución de frecuencias de los patrones de EES, muñeca, dedos y pulgar posterior a un daño de motoneurona superior. MÉTODO: diseño descriptivo de corte transversal prospectivo. Se realizó una medición a 206 sujetos pertenecientes a 17 centros de salud, quienes cumplieron con los criterios de inclusión y firmaron el consentimiento. La evaluación incluyó datos clínicos y la evaluación del patrón de EES (Clasificación de Hefter), muñeca, dedos (Zancolli adaptado) y pulgar (Clasificación de House). RESULTADOS: El análisis consideró cada una de las taxonomías de los patrones de EES evaluados (Hefter I a V). La distribución de frecuencias fue investigada mediante la prueba χ2 de bondad de ajuste, seguida de la inspección post hoc de los residuos estandarizados (z) en cada celda. Se identificaron frecuencias significativamente mayores en: el patrón III de extremidad superior, el patrón cubitalizado neutro de muñeca, el patrón del flexor profundo y mixto de Zancolli adaptado, y en los patrones 3, 4 del pulgar. Ninguna taxonomía se asoció al tiempo de evolución y tipo de ACV. CONCLUSIÓN: El estudio aporta evidencia relevante sobre la distribución frecuencia de patrones espásticos, posterior a un daño de motoneurona superior. La información proporcionada busca apoyar el proceso de decisión terapéutica potenciando la recuperación funcional de la extremidad superior.

BACKGROUND: The evidence regarding people who present superior motor neuron damage and develop a pattern of spasticity in the upper limb (SUL) is limited. This positive sign of the superior motor neuron is associated with both the loss of function and the decreased independence, causing disability and altering life quality. OBJECTIVE: to determine the frequency distribution of SUL, wrist, finger and thumb patterns after superior motor neuron damage. METHOD: prospective cross-sectional descriptive design, the sample consisted of 206 patients belonging to 17 health centers, who met the inclusion criteria and signed the informed consent, approved by the committee of ethics. The study considered a measurement, including clinical data and evaluation of the pattern of SUL (Hefter´s classification), wrist, fingers (adapted Zancolli) and thumb (House Classification). RESULTS: The analysis considered each of the taxonomies of evaluated patterns (Hefter´s I-V). Frequency distribution was investigated by χ2 goodness of fit tests, followed by post hoc inspection of standardized residues (z) in each cell. Significantly higher frequencies were identified in the upper limb pattern III, the neutral cubitalized wrist pattern, the adapted Zancolli deep flexor pattern and in the thumb patterns 3, 4. No taxonomy was associated with the evolution time and type of stroke. CONCLUSION: The study provides with relevant scientific evidence regarding the frequency distribution of spasticity patterns after superior motor neuron damage. The information provided can support the therapeutic decision process by enhancing the functional recovery of upper limb.

Molecular investigation of zoonotic intracellular bacteria in Chilean bats.

Intracellular pathogens were investigated for the first time in 55 Chilean bats belonging to six species. Using a conventional PCR protocol targeting a fragment of the ITS region, 21 bats (38 %) were positive for DNA of Bartonella sp. Molecular characterization of fragments of the gltA, rpoB and fstZ genes and subsequent phylogenetic analysis indicated the presence of diverse genotypes related to Bartonella from bats worldwide. DNA from C. burnetii was investigated using a real-time PCR (qPCR) protocol targeting the IS1111 gene and yielded positive results for 5 individuals (9%), being the first report of C. burnetii in wildlife in Chile. All bats were negative for Rickettsia sp., evaluated by qPCR for the gltA gene, confirming that bats do not act as important reservoirs for Rickettsia. This preliminary survey calls for more comprehensive studies on the epidemiology of these agents, including larger sample sizes, the evaluation of potential transmission routes and spillover potential.

Molecular survey of Bartonella spp. in rodents and fleas from Chile.

The aim of this study was to molecularly survey Bartonella spp. in rodents from the Valdivia Province, Southern Chile and from wild black rat-fleas in Guafo Island, Chilean Patagonia. Thrity-three spleens from synanthropic (Mus musculus, Rattus novergicus and Rattus rattus) and wild (Abrothrix longipilis, Oligoryzomys longicaudatus, Abrothrix sp.) rodents from Valdivia and 39 fleas/flea-pools (Plocopsylla sp. and Nosopsyllus sp.) from R. rattus in Guafo Island were obtained. All samples were screened by high-resolution melting (HRM) real-time PCR for Bartonella ITS locus (190 bp). ITS-Positive samples were further analyzed for two HRM real-time PCR assays targeting Bartonella rpoB (191 bp) and gltA (340 bp) gene fragments. All positive ITS, gltA and rpoB real-time PCR products were purified and sequenced. Bayesian inference trees were built for the gltA and rpoB gene fragments. Bartonella-ITS DNA was detected in 36.3% (12/33) [95% CI (22-53%)] of the tested rodents from Valdivia, being identified in all but O. longicaudatus rodent species captured in this study. ITS DNA was detected in 28% (11/39) [95% CI (16-43%)] of fleas/flea-pools from Guafo Island and identified in both Plocopsylla and Nosopsyllus genera. Sequencing and phylogenic analyses targeting three loci of Bartonella spp. allowed the identification of five genotypes in rodents from Southern Chile, potentially belonging to three different Bartonella spp. Those included Bartonella tribocorum identified from R. rattus, Bartonella rochalimae detected from Abrothix sp., and one novel genotype from uncharacterized Bartonella sp. identified in M. musculus, R. norvegicus, A. longipilis, and Abothrix sp., related to strains previously isolated in Phyllotis sp. from Peru. Additionally, two genotypes of B. tribocorum were identified in fleas from Guafo. In a nutshell, highly diverse and potentially zoonotic Bartonella spp. are described for the first time in wild and synanthropic rodents from Chile, and B. tribocorum was detected in wild back rat fleas from Guafo Island.

Molecular Detection of Gurltia paralysans by Semi-Nested PCR in Cerebrospinal Fluid and Serum Samples from Domestic Cats (Felis catus).

Gurltia paralysans is an angio-neurotropic metastrongyloid nematode that infects domestic and wild cats, invading the veins of the subarachnoid space of the spinal cord and mainly causing progressive paralysis of the pelvic limbs. The definitive diagnosis of feline gurltiosis can only be achieved by post-mortem examination that reveals the presence of the nematode in the spinal cord vein vasculature. An early diagnosis with conclusive results is required since laboratory and imaging findings are not sufficient. Therefore, the purpose of this study was to detect the presence of G. paralysans, via semi-nested PCR, in samples of cerebrospinal fluid (CSF) and the sera of domestic cats naturally infected with the parasite. A total of 12 cats with a diagnosis suggestive of feline gurltiosis were selected, and they underwent a complete neurological and imaging examination. DNA samples were analysed by semi-nested PCR, with universal (AaGp28Sa1/AaGp28Ss1) and specific (Gp28Sa3/Aa28Ss2) primers, for G. paralysans (G. paralysans 18S rRNA gene, partial sequence; ITS 1, 5.8S rRNA gene, and ITS 2, complete sequence; and 28S rRNA gene, partial sequence) and Aelurostrongylus abstrusus, obtaining amplifications of 356 and 300 bp, which indicated the presence or absence of nematode DNA, respectively. The presence of G. paralysans was detected in the CSF of four out of nine cats, and the sera of seven out of seven cats. In the sera analysis of five out of seven cats, a mixed infection with A. abstrusus was found, despite no alterations of the respiratory tract being observed during the necropsies. It is proposed that serum samples could be more effective than CSF in detecting the parasite by PCR analysis. Sequencing analysis showed high percentages of identity with G. paralysans, which indicated the feasibility of detection and the sensitivity/specificity of the method used, suggesting the implementation of semi-nested PCR as a routine diagnostic test for early and timely detection of feline gurltiosis.

Bartonella Infection in Stray Dogs from Central and Southern Chile (Linares and Puerto Montt).

Bartonellae are emerging zoonotic vector-borne pathogens causing a broad spectrum of clinical symptoms in humans and animals, including life-threatening endocarditis. Dogs are infected with a wide range of Bartonella species and infection has been reported in free-roaming dogs from various South American countries. We report a high Bartonella seroprevalence in 82 Chilean stray dogs. More than half of the dogs from Linares (72.7%, n = 66) and Puerto Montt (56.2%, n = 16) were seropositive for Bartonella henselae, Bartonella vinsonii ssp. berkhoffii, or Bartonella clarridgeiae with antibody titers ranging from 1:64 to 1:512. Three dogs (3.6%) were PCR positive for Bartonella sp. Partial sequencing of the gltA gene indicated that two dogs were infected with B. henselae, and one with a strain close to Bartonella vinsonii ssp. vinsonii. Exposure to Bartonella species was common in stray Chilean dogs, as for other South American countries, likely associated with heavy ectoparasite infestation.

Espasticidad como signo positivo de daño de motoneurona superior y su importancia en rehabilitación / Spasticity as a positive sign of superior motor neuron damage and its importance in rehabilitation

Resumen Introducción: La espasticidad, como signo clínico de daño de motoneurona superior, cobra gran importancia al momento de definir su impacto en el proceso rehabilitador. Los objetivos de esta revisión bibliográfica son: analizar la evolución de la espasticidad como concepto, describir los hallazgos actuales en relación con su fisiopatología y analizar su importancia en el proceso rehabilitador. Métodos: Búsqueda bibliográfica durante el segundo semestre del 2017 en bases de datos Pubmed, Scielo, Cochrane y Google Académico, utilizando los términos MeSH: muscle spasticity, physiopathology y stroke. Los límites de búsqueda fueron: textos completos en idioma inglés y español, en humanos y publicados durante los últimos cinco años. Resultados: La fisiopatología de la espasticidad no es causada por un solo mecanismo, sino más bien una intrincada cadena de alteraciones en diferentes redes nerviosas interdependientes. Existiendo dos mecanismos principales: la alteración del control espinal y suprasegmentario y los cambios en las propiedades del sistema músculo-esquelético. Conclusión: La evidencia científica es amplia y aborda el concepto de espasticidad, sus implicancias fisiopatológicas y clínicas. Sin embargo, futuras investigaciones deberían orientar y apoyar las decisiones del equipo rehabilitador, en relación con el manejo clínico.

Abstract Background: Spasticity as a clinical sign of upper motor neuron damage becomes highly important when defining its impact on the rehabilitation process. The aim of this bibliographical review is to examine the evolution of spasticity as a concept, describe the current findings in relation to its pathophysiology and to analyze its importance on the rehabilitation process. Material and methods: A bibliographic search was carried out during 2018 using Pubmed, Scielo, Cochrane and Google Academic databases, using the terms MeSH: 'muscle spasticity', 'physiopathology' and 'stroke'. The searches were limited to full texts in English and Spanish language, published during the last 5 years and for human patients. Results: The physiopathology of spasticity is not caused by a single mechanism, but rather an intricate chain of alterations in different interdependent nerve networks. Analyzed articles describe two main mechanisms, alteration of the control spinal and suprasegmental and changes in the properties of the musculoskeletal system. Conclusion: The scientific evidence is broad and addresses the concept of spasticity, its pathophysiological and clinical implications. However, future research should guide and support the decisions of the rehabilitation team, in relation to their clinical management.

Characterization of the axon initial segment of mice substantia nigra dopaminergic neurons.

The axon initial segment (AIS) is the site of initiation of action potentials and influences action potential waveform, firing pattern, and rate. In view of the fundamental aspects of motor function and behavior that depend on the firing of substantia nigra pars compacta (SNc) dopaminergic neurons, we identified and characterized their AIS in the mouse. Immunostaining for tyrosine hydroxylase (TH), sodium channels (Nav ) and ankyrin-G (Ank-G) was used to visualize the AIS of dopaminergic neurons. Reconstructions of sampled AIS of dopaminergic neurons revealed variable lengths (12-60 µm) and diameters (0.2-0.8 µm), and an average of 50% reduction in diameter between their widest and thinnest parts. Ultrastructural analysis revealed submembranous localization of Ank-G at nodes of Ranvier and AIS. Serial ultrathin section analysis and 3D reconstructions revealed that Ank-G colocalized with TH only at the AIS. Few cases of synaptic innervation of the AIS of dopaminergic neurons were observed. mRNA in situ hybridization of brain-specific Nav subunits revealed the expression of Nav 1.2 by most SNc neurons and a small proportion expressing Nav 1.6. The presence of sodium channels, along with the submembranous location of Ank-G is consistent with the role of AIS in action potential generation. Differences in the size of the AIS likely underlie differences in firing pattern, while the tapering diameter of AIS may define a trigger zone for action potentials. Finally, the conspicuous expression of Nav 1.2 by the majority of dopaminergic neurons may explain their high threshold for firing and their low discharge rate.

Carbon allocation to growth and storage in two evergreen species of contrasting successional status.

PREMISE OF THE STUDY: A prevailing hypothesis in forest succession is that shade-tolerant species grow more slowly than shade-intolerant species, across light conditions, because they prioritize carbon (C) allocation to storage. We examined this hypothesis in a confamilial pair of species, including one of the fastest-growing tree species in the world (Eucalyptus globulus) and a shade-tolerant, slow-growing species (Luma apiculata). METHODS: Seedlings were subjected to one out of four combinations of light (high vs. low) and initial defoliation (90% defoliated vs. nondefoliated) for four months. Growth, C storage concentration in different organs, leaf shedding, and lateral shoot formation were measured at the end of the experiment. KEY RESULTS: Eucalyptus globulus grew faster than L. apiculata in high light, but not in low light. Both species had lower C storage concentration in low than in high light, but similar C storage concentrations in each light condition. Defoliation had no effect on C storage, except in the case of the old leaves of both species, which showed lower C storage levels in response to defoliation. Across treatments, leaf shedding was 96% higher in E. globulus than in L. apiculata while, in contrast, lateral shoot formation was 87% higher in L. apiculata. CONCLUSIONS: In low light, E. globulus prioritized C storage instead of growth, whereas L. apiculata prioritized growth and lateral branching. Our results suggest that shade tolerance depends on efficient light capture rather than C conservation traits.

Pesticide residues in leafy vegetables and human health risk assessment in North Central agricultural areas of Chile.

To investigate pesticide residue concentrations and potential human health risk, a study was conducted in 118 leafy vegetable samples collected in 2014-2015 from the North Central agricultural areas of Chile. The pesticide residues were determined using the multiresidue QuEChERS method by gas chromatography as well as high-performance liquid chromatography. The results indicated that 27% of the total samples contained pesticide residues above the maximum residue limits of each active ingredient. The maximum estimated daily intake obtained for carbon disulphide (CS2), methamidophos, azoxystrobin and cypermethrin were 0.57, 0.07, 0.06 and 0.05 mg kg-1, respectively, which was higher than their acceptable daily intake. It is concluded that inhabitants of the North Central agricultural area of Chile are not exposed to health risks through the consumption of leafy vegetables with the exception of methamidophos. Nevertheless, the high levels of methamidophos detected in leafy vegetables could be considered a potential chronic health risk.

Differential Somatic Ca2+ Channel Profile in Midbrain Dopaminergic Neurons.

UNLABELLED: Dopaminergic (DA) neurons located in the ventral midbrain continuously generate a slow endogenous pacemaker activity, the mechanism of which is still debated. It has been suggested that, in the substantia nigra pars compacta (SNc), the pacemaking relies more on Ca(2+) channels and that the density of L-type Ca(2+) channels is higher in these DA neurons than in those located in the ventral tegmental area (VTA). This might lead to a higher Ca(2+) load in SNc DA neurons and explain their higher susceptibility to degeneration. However, direct evidence for this hypothesis is lacking. We found that the L-type current and channel density are indeed higher in the somata of rat SNc DA neurons and that this current undergoes less inactivation in this region. Nonstationary fluctuation analysis measurements showed a much higher number of L-type channels in the soma of SNc DA neurons, as well as a smaller single-channel conductance, pointing to a possible different molecular identity of L-type channels in DA neurons from the two areas. A major consequence of this is that pacemaking and, even more so, bursting are associated with a larger Ca(2+) entry through L-type channels in SNc DA neurons than in their VTA counterparts. Our results establish a molecular and functional difference between two populations of midbrain DA neurons that may contribute to their differential sensitivity to neurodegeneration. SIGNIFICANCE STATEMENT: Dopamine neurons from the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) are involved in various brain functions, such as movement initiation and goal directed behavior, respectively. This work shows that, although both neurons fire in a similar regular and slow pacemaker mode, this firing activity is supported by different calcium channel landscapes. Indeed, the L-type calcium current is larger in the soma of dopamine neurons of the SNc, leading to a higher charge transfer through L-type channels during pacemaking and bursting. Therefore, these neurons may be physiologically exposed to a larger stress than their neighbors from the VTA.