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Allelopathy is a common and important stressor that shapes plant communities and can alter soil microbiomes, yet little is known about the direct effects of allelochemical addition on bacterial and fungal communities or the potential for allelochemical-selected microbiomes to mediate plant performance responses, especially in habitats naturally structured by allelopathy. Here, we present the first community-wide investigation of microbial mediation of allelochemical effects on plant performance by testing how allelopathy affects soil microbiome structure and how these microbial changes impact germination and productivity across 13 plant species. The soil microbiome exhibited significant changes to 'core' bacterial and fungal taxa, bacterial composition, abundance of functionally important bacterial and fungal taxa, and predicted bacterial functional genes after the addition of the dominant allelochemical native to this habitat. Furthermore, plant performance was mediated by the allelochemical-selected microbiome, with allelopathic inhibition of plant productivity moderately mitigated by the microbiome. Through our findings, we present a potential framework to understand the strength of plant-microbial interactions in the presence of environmental stressors, in which frequency of the ecological stress may be a key predictor of microbiome-mediation strength.
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Alelopatia , Microbiota , Plantas , Microbiologia do Solo , Bactérias , Solo/química , Feromônios/farmacologiaRESUMO
A variety of cognitive, behavioural, and emotional impairments have been reported in the literature that are associated with the resection of the temporal cortex. Klüver-Bucy syndrome is one infrequently reported disorder in the paediatric population. This paper describes the neuropsychological findings of a female paediatric patient at 7 and 10 years of age with a diagnosis of partial Klüver-Bucy syndrome (pKBS) following total resection of the amygdala and right hippocampus to resect a glioma. The patient presented emotional problems, aggressiveness, hypermetamorphosis, social indifference, and behavioural dysexecutive syndrome, which was found at both 7 and 10 years, but with a decrease in the severity of alterations in attention, impulsivity, hyperactivity, and aggressive behaviour in a second evaluation after she had a neuropsychological intervention. These findings describe the neuropsychological profile of paediatric case with resection of the amygdala and right temporal lobe.
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Apatia , Síndrome de Kluver-Bucy , Humanos , Feminino , Criança , Síndrome de Kluver-Bucy/complicações , Lobo Temporal/cirurgia , Tonsila do Cerebelo/cirurgia , HipocampoRESUMO
An increased number of dengue cases with neurological complications have been reported in recent years. The lack of reliable animal models for dengue has hindered studies on dengue virus (DENV) pathogenesis and cellular tropism in vivo. We further investigate the tropism of DENV for the human central nervous system (CNS), characterizing DENV interactions with cell surface proteins in human CNS cells by virus overlay protein binding assays (VOPBA) and coimmunoprecipitations. In VOPBA, three membrane proteins (60, 70, and 130 kDa) from the gray matter bound the entire virus particle, whereas only a 70 kDa protein bound in white matter. The coimmunoprecipitation assays revealed three proteins from gray matter consistently binding virus particles, one clearly distinguishable protein (~32 kDa) and two less apparent proteins (100 and 130 kDa). Monoclonal anti-NS3 targeted the virus protein in primary cell cultures of human CNS treated with DENV-2, which also stained positive for NeuH, a neuron-specific marker. Thus, our results indicate (1) that DENV-2 exhibited a direct tropism for human neurons and (2) that human neurons sustain an active DENV replication as was demonstrated by the presence of the NS3 viral antigen in primary cultures of these cells treated with DENV-2.
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Vírus da Dengue/fisiologia , Proteínas Virais/metabolismo , Replicação Viral , Adolescente , Encéfalo/virologia , Criança , Vírus da Dengue/metabolismo , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Imunoprecipitação , Técnicas In Vitro , Masculino , Ligação ProteicaRESUMO
During the COVID-19 pandemic, patients in need of neurosurgical care suffered. Elective procedures were postponed, and emergency care visits decreased. Healthcare-associated ventriculitis (HAV) is a serious problem in children, with poor outcomes and frequent relapses. Our objective was to describe the clinical characteristics and the factors associated with a first HAV in children during two years of the pandemic. A retrospective cross-sectional study was performed from January 2021 to December 2022. The inclusion criteria were patients who developed a first HAV after a primary cerebrospinal fluid diversion procedure. The controls included patients without a first infection. Intraoperative and clinical data were extracted from medical records. A total of 199 CSF diversion surgeries were registered. A first infection occurred in 17 patients (8.5%), including 10 with external ventricular drain (EVD) and 6 with ventricular shunts. Gram-positive cocci were identified in 70.6%. Six patients recovered uneventfully, eight had relapse or superinfections, and three eventually died. Twenty patients were included as controls. Factors associated with a first infection were a younger age (median 9 vs. 102 months, p < 0.01), malnutrition (23.5% vs. 0%, p = 0.03), and an EVD placement (58.8% vs. 10%, p = 0.03). None of the intraoperative factors showed statistically significant differences. The rate of HAV was high. Most cases presented in children <1 year and with an EVD.
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Nearly 75 years after the first woman neurosurgeon was trained in Latin America, the field of neurosurgery is changing and the prominence of women neurosurgeons within the specialty is increasing. By researching the histories of individual physicians and neurosurgeons, as well as neurosurgical departments and societies, we present, for the first time, the history of the women in neurosurgery in Latin America. Women neurosurgeons in the region have made notable progress, inspiring subsequent generations and actively participating in organized neurosurgery, medical leadership outside neurosurgery, academic neurosurgery, and leadership in contemporary society. The establishment of "Women in Neurosurgery" networks and organizations has been important to the success of many of these efforts. This collaborative study, which identifies the known women neurosurgeons in Latin America for the first time, may serve to provide background and context for further contributions of women neurosurgeons for our profession and our patients.
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Neurocirurgiões/história , Neurocirurgia/história , Procedimentos Neurocirúrgicos/história , Médicas/história , Feminino , História do Século XX , História do Século XXI , Humanos , América Latina , Neurocirurgiões/tendências , Neurocirurgia/tendências , Procedimentos Neurocirúrgicos/tendências , Médicas/tendênciasRESUMO
BACKGROUND: Recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic represents an important negative impact on global training of neurosurgery residents. Even before the pandemic, discrimination is a challenge that neurosurgical residents have consistently faced. In the present study, we evaluated discriminatory conditions experienced by residents during their neurosurgical training in Mexico before the SARS-CoV-2 pandemic. METHODS: An electronic survey of 18 questions was sent among residents registered in the Mexican Society of Neurological Surgery (MSNS), between October 2019 and July 2020. Statistical analysis was made in IBM SPSS Statistics 25. The survey focused on demographic characteristics, discrimination, personal satisfaction, and expectations of residents. RESULTS: A response rate of 50% (132 of 264 residents' members of MSNS) was obtained and considered for analysis. Median age was 30.06 ± 2.48 years, 5.3% (n = 7) were female and 16.7% (n = 22) were foreigners undergoing neurosurgical training in Mexico. Approximately 27% of respondents suffered any form of discrimination, mainly by place of origin (9.1%), by gender (8.3%) or by physical appearance (6.1%). About 42.9% (n = 3) of female residents were discriminated by gender versus 6.4% (n = 8) of male residents (P = 0.001); while foreign residents mentioned having suffered 10 times more an event of discrimination by place of origin compared to native Mexican residents (36.4% vs. 3.6%, P < 0.001). CONCLUSION: This manuscript represents the first approximation to determine the impact of discrimination suffered by residents undergoing neurosurgical training in Mexico before the SARS-CoV-2 pandemic.
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BACKGROUND: The pineal anlage tumor is a very infrequent malign neoplasm. Even though it has been documented in literature, it is not listed yet in the World Health Organization's last nervous system classification (2007). It is a primitive pineal tumor with neuroepithelial and ectomesenchyme differentiation. Due to its low frequency, the understanding of its biological behavior and a suitable treatment are incomplete. In a search performed in PubMed with the term pineal anlage tumor, only seven informed cases were identified between 1989 and 2011. CLINICAL CASE: An 8-month-old infant was brought to medical attention because he had a progressive enlargement of the cephalic perimeter, and convergent strabismus of two months of evolution. A pineal tumor was identified. The histology showed glial tissue, ganglia cells, pigmented neuroepithelium and striate muscle cells. A ventriculoperitoneal derivation was done to diminish hydrocephalic pressure and also to led the complete surgical resection. The patient was treated with two courses of chemotherapy with carboplatine, ifosfamide and mesna. One year after the treatment, the patient is asymptomatic. CONCLUSIONS: This is the first case reported in Spanish language. Given that it is a really infrequent tumor, it could be misdiagnosed as teratome, melanotic or mesoblastic medulloblastoma, or a melanotic neuroectodermal tumor of childhood (melanotic prognoma).
INTRODUCCIÓN: el tumor pineal anlage es una neoplasia maligna muy poco frecuente. Aunque ya ha sido informado en la literatura, aún no se encuentra listado en la última clasificación de los tumores del sistema nervioso central de la Organización Mundial de la Salud publicada en 2007. Es un tumor primario de la pineal con diferenciación neuroepitelial y ectomesenquimal. Debido a su poca frecuencia, el entendimiento de su comportamiento biológico y su tratamiento apropiado son incompletos. En una búsqueda realizada en PubMed como pineal anlage tumor solo se identificaron siete casos informados entre 1989 y 2011. CASO CLÍNICO: niño de ocho meses de edad que fue llevado a consulta por aumento progresivo del perímetro cefálico y estrabismo convergente de dos meses de evolución. Se identificó tumor pineal conformado por glia, células ganglionares, neuroepitelio pigmentado y células musculares estriadas. Se realizó derivación ventrículo-peritoneal para mitigar la hidrocefalia y resección quirúrgica completa. El paciente recibió dos cursos de quimioterapia con carboplatino, ifosfamida y mesna. Al año permanecía asintomático. CONCLUSIONES: el caso constituye el primero que se describe en lengua española. Dada su rareza, esta entidad puede ser mal diagnosticada como teratoma, meduloblastoma con diferenciación mioblástica y melanótica o tumor neuroectodérmico melanótico de la infancia (progonoma melanótico).
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Neoplasias Encefálicas/patologia , Glândula Pineal , Pinealoma/patologia , Humanos , Lactente , Idioma , MasculinoRESUMO
Segmental neurofibromatosis (NF-5) is an extremely rare variant of neurofibromatosis involving a single extremity without pathologic features beyond the midline. A case of segmental neurofibromatosis involving the sciatic nerve and its branches is presented with a detailed description of the patient's preoperative findings plus postoperative course through 1-year follow-up. Clinical, histologic, and genetic findings are given along with a brief review of the literature on segmental neurofibromatosis. Last, treatment options and postoperative care recommendations are provided.
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Neurofibromatoses/patologia , Neoplasias do Sistema Nervoso Periférico/patologia , Nervo Isquiático/patologia , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Neurofibromatoses/fisiopatologia , Neurofibromatoses/cirurgia , Neoplasias do Sistema Nervoso Periférico/fisiopatologia , Neoplasias do Sistema Nervoso Periférico/cirurgia , Proteínas S100/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/cirurgiaRESUMO
The physiological role and transcriptional expression of Rhizobium etli sigma factors rpoH1 and rpoH2 are reported in this work. Both rpoH1 and rpoH2 were able to complement the temperature-sensitive phenotype of an Escherichia coli rpoH mutant. The R. etli rpoH1 mutant was sensitive to heat shock, sodium hypochlorite and hydrogen peroxide, whereas the rpoH2 mutant was sensitive to NaCl and sucrose. The rpoH2 rpoH1 double mutant had increased sensitivity to heat shock and oxidative stress when compared with the rpoH1 single mutant. This suggests that in R. etli, RpoH1 is the main heat-shock sigma factor, but a more complete protective response could be achieved with the participation of RpoH2. Conversely, RpoH2 is involved in osmotic tolerance. In symbiosis with bean plants, the R. etli rpoH1 and rpoH2 rpoH1 mutants still elicited nodule formation, but exhibited reduced nitrogenase activity and bacterial viability in early and late symbiosis compared with nodules produced by rpoH2 mutants and wild-type strains. In addition, nodules formed by R. etli rpoH1 and rpoH2 rpoH1 mutants showed premature senescence. It was also determined that fixNf and fixKf expression was affected in rpoH1 mutants. Both rpoH genes were induced under microaerobic conditions and in the stationary growth phase, but not in response to heat shock. Analysis of the upstream region of rpoH1 revealed a sigma70 and a probable sigmaE promoter, whereas in rpoH2, one probable sigmaE-dependent promoter was detected. In conclusion, the two RpoH proteins operate under different stress conditions, RpoH1 in heat-shock and oxidative responses, and RpoH2 in osmotic tolerance.
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Proteínas de Choque Térmico/metabolismo , Pressão Osmótica , Rhizobium etli/fisiologia , Fator sigma/metabolismo , Estresse Fisiológico , Sequência de Bases , Fabaceae/microbiologia , Fabaceae/fisiologia , Regulação Bacteriana da Expressão Gênica , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico , Dados de Sequência Molecular , Mutação , Estresse Oxidativo , Regiões Promotoras Genéticas , Rhizobium etli/genética , Nódulos Radiculares de Plantas/microbiologia , Nódulos Radiculares de Plantas/fisiologia , Fator sigma/genética , SimbioseRESUMO
Algunas cepas de estafilococo han desarrollado resistencia a la meticilina (ERM) y a antibióticos congéneres; este es un fenómeno común en Europa y Estados Unidos. Para su detección se requieren procedimientos especiales en el laboratorio, pues generalmente escapa a la identificación por los métodos comunes. Este estudio prospectivo se efectuó para determinar la proporción de cepas de estafilococo resistentes a meticilina y algunos otros antibióticos en el Hospita General Regional de León, Guanajuato. Se utilizó el procedimiento de dilución en caldo suplementado con sodio y cationes en cepas aisladas de muestras clínicas, durante el periodo comprendido entre agosto de 1990 y febrero de 1992. Se estudiaron 61 cepas de Staphylococcus aureus y 22 de estafilococo coagulasa-negativo; se encontró una resistencia global a la meticilina de 24.1 por ciento, aunque la cifra fue marcadamente diferente para las primeras (13.1 por ciento). que para las segundas (54.6 por ciento). No se encontraron cepas resistentes a la vancomicina. Considerando aisladamente las cepas de ERM, se encontraron como alternativas terapéuticas la vancomicina, rifampicina, ciprofloxacina y el trimetoprim con sulfametoxazol, ya que en todos los caos las sensibilidad fue superior a 85 por ciento. El resto de antibióticos probados (aminoglucósidos, eritromicina, tetraciclina, clorafenicol y cefalosporinas) no se consideraron buenas alternativas terapéuticas debido a los bajos índices de sensibilidad. Se comenta la necesidad de conocer mejor el fenómeno de resistencia a meticilina en hospitales mexicanos