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1.
Surg Neurol Int ; 14: 97, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37025519

RESUMO

Background: Cisternostomy is a surgical technique thought of and developed as an option for severe brain trauma treatment. It demands a particular knowledge and skill to microsurgically approach basal cisterns and effectively manipulate their contents. To perform this procedure safely, the anatomy and pathophysiology must be clearly understood. Methods: Detailed microscopic dissection and anatomical review were done, after a detailed reading of facts and recent publications about cisternostomy. Cisternal pathways and landmark planning are described and augmented using a new method to show de arachnoid borders. Finally, a brief discussion is written as a synopsis. Results: Cisternostomy requires thorough microscopic knowledge and microsurgical skills. This paper intends to provide information to understand better the anatomy related, thus, easing the learning curve. The technique used to show arachnoid borders, complementing cadaveric and surgical images, was useful for this purpose. Conclusion: To perform this procedure safely, it is mandatory to handle microscopic details of cistern anatomy. Reaching a core cistern is necessary to assure effectiveness. This procedure needs, as well, surgical step-by-step landmark planning and performing. Cisternostomy could be a life-saving procedure and a new powerful tool for severe brain trauma treatment. Evidence is being collected to support its indications.

2.
Front Microbiol ; 12: 713189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867840

RESUMO

The genus Pseudogymnoascus represents a diverse group of fungi widely distributed in different cold regions on Earth. Our current knowledge of the species of Pseudogymnoascus is still very limited. Currently, there are only 15 accepted species of Pseudogymnoascus that have been isolated from different environments in the Northern Hemisphere. In contrast, species of Pseudogymnoascus from the Southern Hemisphere have not yet been described. In this work, we characterized four fungal strains obtained from Antarctic marine sponges. Based on multilocus phylogenetic analyses and morphological characterizations we determined that these strains are new species, for which the names Pseudogymnoascus antarcticus sp. nov., Pseudogymnoascus australis sp. nov., Pseudogymnoascus griseus sp. nov., and Pseudogymnoascus lanuginosus sp. nov. are proposed. Phylogenetic analyses indicate that the new species form distinct lineages separated from other species of Pseudogymnoascus with strong support. The new species do not form sexual structures and differ from the currently known species mainly in the shape and size of their conidia, the presence of chains of arthroconidia, and the appearance of their colonies. This is the first report of new species of Pseudogymnoascus not only from Antarctica but also from the Southern Hemisphere.

3.
Data Brief ; 37: 107258, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34277905

RESUMO

Aneurysm clipping requires the proficiency of several skills, yet the traditional way of practicing them has been recently challenged. The use of simulators could be an alternative educational tool. The aim of this data analysis is to provide further evaluation of a reusable low-cost 3D printed training model we developed for aneurysm clipping [1]. The simulator was designed to replicate the bone structure, arteries and targeted aneurysms. Thirty-two neurosurgery residents performed a craniotomy and aneurysm clipping using the model and then filled out a survey. The survey was designed in two parts: a 5-point Likert scale questionnaire and three questions requiring written responses [1]. Two dimensions of the model were evaluated by the questionnaire: the face validity, assessed by 5 questions about the realism of the model, and the content validity, assessed by 6 questions regarding the usefulness of the model during the different steps of the training procedure. The three questions requiring written responses referred to the strengths and weaknesses of the simulator and a global yes/no question as to whether or not they would repeat the experience. Demographic data, experience level and survey responses of the residents were grouped in a dataset [2]. A descriptive analysis was performed for each dimension. Then, the groups were compared according to their level of expertise (Junior and Senior groups) with an independent sample t-test. A Confirmatory Factor Analysis (CFA) was estimated, using a Weighted Least Squares Mean Variance adjusted (WLSMV) which works best for the ordinal data [3]. Fitness was calculated using chi-square (χ2) test, Comparative Fit Index (CFI), Tucker-Lewis Index (TLI), and the Root Mean Square Error of Approximation (RMSEA). A non-significant χ2, CFI and TLI greater than 0.90 and RMSEA < 0.08 were considered an acceptable fit [4]. All data analysis was performed using IBM SPSS 23.0 statistical software. Data are reported as mean + standard deviation (SD). A probability p < 0.05 was considered significant. Exploratory Factor Analysis was done to explore the factorial structure of the 11-items scale in the sample, first we performed a principal components analysis. The Kaiser-Meyer-Olkin measure verified the sampling adequacy for the analysis (KMO = 0.784; Bartlett's Test of Sphericity χ2 (55) = 243.44, p < .001), indicating correlation is adequate for factor analysis. Considering Eigen values greater than 1, a two-factor solution explained 73.1% of the variance but left one item in factor 2 (Q 11). The results of this factor analysis are presented in Table 1. Confirmatory Factor Analysis, considering only the 10 items in the first factor (removing question 11 of our model), was performed. This model reached the following fit: χ2 (35) = 38.821, p > .05; CFI = 0.997; TLI = 0.996; RMSEA 0.058, without any error terms to exhibit covariance. Regarding the reliability of the questionnaire, the internal consistency was explored in the 10 items selected in the confirmatory factor analysis with an alpha coefficient (α = 0.941).

10.
Front Microbiol ; 10: 2675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824460

RESUMO

Cold-adapted fungi isolated from Antarctica, in particular those belonging to the genus Pseudogymnoascus, are producers of secondary metabolites with interesting bioactive properties as well as enzymes with potential biotechnological applications. However, at genetic level, the study of these fungi has been hindered by the lack of suitable genetic tools such as transformation systems. In fungi, the availability of transformation systems is a key to address the functional analysis of genes related with the production of a particular metabolite or enzyme. To the best of our knowledge, the transformation of Pseudogymnoascus strains of Antarctic origin has not been achieved yet. In this work, we describe for the first time the successful transformation of a Pseudogymnoascus verrucosus strain of Antarctic origin, using two methodologies: the polyethylene glycol (PEG)-mediated transformation, and the electroporation of germinated conidia. We achieved transformation efficiencies of 15.87 ± 5.16 transformants per µg of DNA and 2.67 ± 1.15 transformants per µg of DNA for PEG-mediated transformation and electroporation of germinated conidia, respectively. These results indicate that PEG-mediated transformation is a very efficient method for the transformation of this Antarctic fungus. The genetic transformation of Pseudogymnoascus verrucosus described in this work represents the first example of transformation of a filamentous fungus of Antarctic origin.

11.
Rev Med Chil ; 147(7): 852-859, 2019 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-31859983

RESUMO

BACKGROUND: Classification of growth hormone (GH) - secreting tumors by the granular pattern might predict their clinical behavior in acromegalic patients. There are several other prognostic factors. AIM: To compare the features at presentation and cure rates of patients with GH secreting tumors according to the granular pattern, and to define independent prognostic factors for surgical treatment in these patients. MATERIAL AND METHODS: A retrospective, observational study of 85 active acromegalic patients surgically treated in two medical centers. RESULTS: Seventy-four patients (87%) were classified as having densely granulated (DG) and 11 (13%) as sparsely granulated (SG) tumors. The latter were less active biochemically, had a higher rate of macroadenoma and cavernous sinus invasion and had a lower rate of biochemical cure than the DG group. Several characteristics were associated with disease persistence but only age (Odds ratio (OR) = 0.93) and cavernous sinus invasion (OR = 21.7) were independently associated in the logistic regression model. CONCLUSIONS: The sparsely granulated pattern is associated with a more aggressive behavior, but the main determinants of prognosis are age and cavernous sinus invasion.


Assuntos
Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Adulto , Feminino , Adenoma Hipofisário Secretor de Hormônio do Crescimento/diagnóstico por imagem , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
12.
Rev. méd. Chile ; 147(7): 852-859, jul. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1058614

RESUMO

Background: Classification of growth hormone (GH) - secreting tumors by the granular pattern might predict their clinical behavior in acromegalic patients. There are several other prognostic factors. Aim: To compare the features at presentation and cure rates of patients with GH secreting tumors according to the granular pattern, and to define independent prognostic factors for surgical treatment in these patients. Material and Methods: A retrospective, observational study of 85 active acromegalic patients surgically treated in two medical centers. Results: Seventy-four patients (87%) were classified as having densely granulated (DG) and 11 (13%) as sparsely granulated (SG) tumors. The latter were less active biochemically, had a higher rate of macroadenoma and cavernous sinus invasion and had a lower rate of biochemical cure than the DG group. Several characteristics were associated with disease persistence but only age (Odds ratio (OR) = 0.93) and cavernous sinus invasion (OR = 21.7) were independently associated in the logistic regression model. Conclusions: The sparsely granulated pattern is associated with a more aggressive behavior, but the main determinants of prognosis are age and cavernous sinus invasion.


Assuntos
Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Prognóstico , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Adenoma Hipofisário Secretor de Hormônio do Crescimento/diagnóstico por imagem
17.
World Neurosurg ; 97: 645-651, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27535633

RESUMO

Pontificia Universidad Católica de Chile's medical school was founded in 1929. An interest in neurosurgical development arose in the minds of the Dean, Dr. Cristobal Espíldora, and the Chief of Surgery, Dr. Rodolfo Rencoret, in 1946. They encouraged and supported Dr. J. Ricardo Olivares to specialize in Neurosurgery with Professor H. Olivecrona in Stockholm, Sweden. The first neurosurgical procedure in the Hospital Clínico de la Universidad Católica was performed in 1950. Since then, intensive efforts have been made to develop neurosurgery and its science. As a result, it is now a center capable of achieving high-quality standards in vascular, oncologic, and endoscopic neurosurgery; stereotactic and radiosurgery; complex spine surgery; pediatric neurosurgery; and epilepsy surgery. This article tells the story of a university hospital neurosurgery service in a country at the southern end of the world and how it became one of the most important neurosurgical centers in Chile and South America.


Assuntos
Departamentos Hospitalares/história , Hospitais Universitários/história , Neurocirurgia/história , Faculdades de Medicina/história , Chile , História do Século XX
19.
Medwave ; 15(7): e6207, 2015 Aug 10.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26335141

RESUMO

INTRODUCTION: Acute myeloid leukemia has a high mortality if untreated. Hematopoietic stem cell transplantation is the only curative treatment so far. Patients who are not eligible to receive a transplant can be treated with hypomethylating agents that have shown to improve disease-free and overall survival. OBJECTIVE: Retrospective description of the clinical characteristics of patients suffering from advanced myelodysplastic syndrome and acute myeloid leukemia that were treated with a hypomethylating agent as well as its adverse effects and response to treatment. METHODS: This report shows our experience in 38 patients with acute myeloid leukemia treated with azacitidine or palliative treatment. RESULTS: Azacitidine was able to prolong survival in 80% of patients with a high incidence of adverse effects and negative impact on quality of life. Most of the patients treated with palliative intent died in the first month after diagnosis. CONCLUSIONS: Azacitidine can prolong survival but with significant adverse effects. Untreated patients had a high early mortality.


INTRODUCCIÓN : La leucemia mieloide aguda tiene una alta mortalidad sin tratamiento. El trasplante hematopoyético es la única estrategia curativa hasta ahora. Los pacientes que tienen contraindicaciones para el trasplante, pueden ser tratados con fármacos hipometilantes que han mostrado mejorar la sobrevida libre de enfermedad y sobrevida global. OBJETIVOS: Describir las características clínicas de los pacientes con síndrome mielodisplásico avanzado y leucemia mieloide aguda, las respuestas logradas y efectos adversos del tratamiento con el fármaco hipometilante. MÉTODOS: Este reporte muestra nuestra experiencia en 38 pacientes con leucemia mieloide aguda tratados con azacitidina o con tratamiento paliativo. RESULTADOS: La azacitidina permitió alargar la sobrevida en 80% de los pacientes con alta incidencia de efectos adversos y afectación de la calidad de vida. La mayoría de los pacientes tratados con intención paliativa, fallecieron en el primer mes post diagnóstico. CONCLUSIONES: La azacitidina permite prolongar la sobrevida, pero con efectos adversos considerables.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Azacitidina/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Cuidados Paliativos/métodos , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/efeitos adversos , Azacitidina/efeitos adversos , Feminino , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
20.
Rev Med Chil ; 143(6): 809-11, 2015 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-26230566

RESUMO

Thrombotic thrombocytopenic purpura, an immune/non-immune thrombotic microangiopathy (TTP/TMA) is associated with high morbidity and mortality, even with appropriate treatment. In patients refractory to standard treatment with plasmapheresis there is no certainty about the best therapeutic strategy. This report shows our experience in eight refractory patients who survived after treatment with rituximab.


Assuntos
Púrpura Trombocitopênica Trombótica/tratamento farmacológico , Rituximab/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Rituximab/farmacocinética , Adulto Jovem
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