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1.
Rev Biol Trop ; 64(2): 913-26, 2016 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-29451977

RESUMO

The distribution of carbon in "Blue Carbon" ecosystems such as mangroves is little known, when compared with the highly known terrestrial forests, despite its particular and recognized high productivity and carbon storage capacity. The objective of this study was to analyze the above ground biomass (AGB) of the species Rhizophora mangle and Avicennia germinans from the Marine Protected Area of Distrito de Manejo Integrado (DMI), Cispatá-Tinajones-La Balsa, Caribbean Colombian coast. With official authorization, we harvested and studied 30 individuals of each species, and built allometric models in order to estimate AGB. Our AGB results indicated that the studied mangrove forests of the DMI Colombian Caribbean was of 129.69 ± 20.24 Mg/ha, equivalent to 64.85 ± 10.12 MgC/ha. The DMI has an area of 8 570.9 ha in mangrove forests, and we estimated that the total carbon potential stored was about 555 795.93 Mg C. The equations generated in this study can be considered as an alternative for the assessment of carbon stocks in AGB of mangrove forests in Colombia; as other available AGB allometric models do not discriminate mangrove forests, despite being particular ecosystems. They can be used for analysis at a more detailed scale and are considered useful to determine the carbon storage potential of mangrove forests, as a country alternative to support forest conservation and emission reduction strategies. In general, the potential of carbon storage from Colombian Caribbean mangrove forests is important and could promote the country leadership of the "blue carbon" stored.


Assuntos
Biomassa , Carbono/análise , Florestas , Rhizophoraceae/metabolismo , Carbono/metabolismo , Região do Caribe , Colômbia , Modelos Biológicos , Rhizophoraceae/classificação
2.
J Pathol Inform ; 15: 100368, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38496781

RESUMO

Soft tissue tumors (STTs) pose diagnostic and therapeutic challenges due to their rarity, complexity, and morphological overlap. Accurate differentiation between benign and malignant STTs is important to set treatment directions, however, this task can be difficult. The integration of machine learning and artificial intelligence (AI) models can potentially be helpful in classifying these tumors. The aim of this study was to investigate AI and machine learning tools in the classification of STT into benign and malignant categories. This study consisted of three components: (1) Evaluation of whole-slide images (WSIs) to classify STT into benign and malignant entities. Five specialized soft tissue pathologists from different medical centers independently reviewed 100 WSIs, representing 100 different cases, with limited clinical information and no additional workup. The results showed an overall concordance rate of 70.4% compared to the reference diagnosis. (2) Identification of cell-specific parameters that can distinguish benign and malignant STT. Using an image analysis software (QuPath) and a cohort of 95 cases, several cell-specific parameters were found to be statistically significant, most notably cell count, nucleus/cell area ratio, nucleus hematoxylin density mean, and cell max caliper. (3) Evaluation of machine learning library (Scikit-learn) in differentiating benign and malignant STTs. A total of 195 STT cases (156 cases in the training group and 39 cases in the validation group) achieved approximately 70% sensitivity and specificity, and an AUC of 0.68. Our limited study suggests that the use of WSI and AI in soft tissue pathology has the potential to enhance diagnostic accuracy and identify parameters that can differentiate between benign and malignant STTs. We envision the integration of AI as a supportive tool to augment the pathologists' diagnostic capabilities.

4.
Am J Surg Pathol ; 44(2): 271-279, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31688141

RESUMO

We report 21 cases of a distinctive and unique vascular tumor which we propose to be a pure lymphatic-type angiosarcoma characterized by architectural and growth characteristics of angiosarcoma, cytologic, and immunohistochemical features of lymphatic differentiation, a prominent lymphocytic infiltrate, and variable nuclear grade. Patients included 12 males and 9 females with a median age of 65 years (range: 32 to 95 y). Tumors involved the head and neck (n=11), lower extremities (n=5), trunk (n=4), and upper extremity (n=1) and were located superficially in the dermis and/or subcutis. Tumors were designated "low grade" (n=10) when the nuclear grade was low, and vascular channel formation was evident throughout but with multilayering of endothelium within the vessels. Cases were designated "high grade" (n=11) when nuclei appeared higher grade with more rounded contours and prominent nucleoli and when solid areas predominated over vascular channel formation. A striking feature of both groups was the presence of a dense, lymphocytic infiltrate with occasional germinal center formation. All cases strongly and diffusely expressed at least 1 lymphatic marker (21/21) with podoplanin (17/19) and Prox-1 (11/11) more commonly expressed than LYVE-1 (5/10). No consistent molecular alteration was identified. Follow-up on 17 patients (median: 41 mo, mean: 54 mo) showed 10 patients were alive without disease, 5 were alive with disease, 1 died of other cause, and 1 died of disease. Local recurrence developed in 9 cases and metastasis in 2 cases, although neither correlated with grade as defined. On the basis of clinical follow-up to date, the natural history of lymphatic-type angiosarcoma appears to be more favorable than other forms of cutaneous angiosarcoma.


Assuntos
Hemangioendotelioma/patologia , Hemangiossarcoma/patologia , Linfangiossarcoma/patologia , Neoplasias Cutâneas/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Feminino , Seguimentos , Hemangioendotelioma/diagnóstico , Hemangioendotelioma/mortalidade , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/mortalidade , Humanos , Linfangiossarcoma/diagnóstico , Linfangiossarcoma/mortalidade , Vasos Linfáticos/patologia , Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/mortalidade , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/mortalidade , Análise de Sobrevida
5.
Cytojournal ; 4: 13, 2007 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-17587453

RESUMO

BACKGROUND: Pancreatic adenocarcinoma comprises 85% of all cases of pancreatic malignancies. From a diagnostic standpoint, these tumors are readily diagnosed by fine needle aspiration, with an accuracy of greater than 90%; however it is often difficult to ascertain whether these are primary or metastatic in nature. This study was undertaken to see the usefulness of CK19, CA19-9 and a newly described marker, SMAD4 in confirming the pancreatic origin of these tumors. Briefly, SMAD4 (DPC4) is a tumor-suppressor gene located on chromosome 18q which has been shown to mediate the downstream effects of TGF-beta superfamily signaling, resulting in growth inhibition. The loss of SMAD4, which as been reported to occur in 55% of pancreatic ductal adenocarcinomas may lead to up regulation of cell cycle proteins and hence increase cellular proliferation. In addition, SMAD4 has been suggested to possibly have prognostic potential, with the presence of SMAD4, indicating shorter survival after resection. DESIGN: Clinical data was reviewed to identify patients with proven, primary pancreatic adenocarcinoma. A total of 25 patients with diagnostic material from fine needle aspiration cell blocks, were retrieved from our files at Emory University Hospital. In addition cell blocks from clinically diagnosed non-pancreatic adenocarcinomas were also selected as controls for this study (10 cases of colonic adenocarcinoma, 10 cases of pulmonary adenocarcinoma, 10 cases of breast ductal carcinoma and 10 cases of ovarian mucinous adenocarcinoma). Formalin fixed, paraffin-embedded sections from these were stained with SMAD4, CK19, and CA19-9, using pressure cooker antigen retrieval, labeled polymer HRP (DAKO), and the DAKO autostainer. RESULTS: Immunohistochemical staining was reviewed based on intensity (negative, low-positive, and high-positive) and percentage of cells. In primary pancreatic ductal adenocarcinoma, CK 19 showed diffuse cytoplasmic positivity in 23 of 25 cases, CA 19-9 showed apical cytoplasmic staining in all 25 cases, and SMAD4 showed nuclear staining in 20 of 25 cases. In the control group comprising of non-pancreatic adenocarcinoma SMAD4 was negative (100%) in all 10 cases of colonic and pulmonary adenocarcinoma. However 1 of 10 cases (10%) of breast and ovarian adenocarcinoma did show low positivity nuclear staining. However the expression of CA19-9 and CK19 was more variable in these different non-pancreatic malignancies. CONCLUSION: Pancreatic adenocarcinoma showed positive immunohistochemical staining for SMAD4 in 80%, CK19 in 100% and CA19-9 in 100% of the selected cases. These markers, when used as a panel, may confirm the diagnosis of pancreatic adenocarcinoma in fine needle aspiration samples, and help in differentiating from metastatic adenocarcinoma. This may help in determination of appropriate surgical and chemotherapeutic options.

6.
Diagn Cytopathol ; 34(11): 719-23, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17041954

RESUMO

Pneumocystis jiroveci (Pj; formerly Pneumocystis carinii) is an opportunistic pathogen causing life-threatening pneumonia (Pneumocystis pneumonia) in immunosuppressed individuals. Its diagnosis is dependent on identification in bronchoalveolar lavage (BAL) specimens. Gomori's methenamine silver nitrate (GMS) stain has been advocated to highlight the organisms in BAL specimens. This study was performed to determine the utility of reflex GMS staining on all BAL specimens for identifying Pj.All BAL specimens from years 2000 to 2004 were processed as cytospins and stained with Papanicolaou (Pap) and GMS stains. A total of 2,984 BAL specimens were identified. A total of 116 (3.9% of total BAL) BAL specimens were diagnostic of Pj. The diagnostic specimens were grouped as follows: 103 (88.8% of total positive cases) Pj identified with both Pap and GMS staining; 11 (9.5% of total positive cases) Pj identified only with Pap staining; and 2 (1.7% of total positive cases) Pj identified only with GMS staining. In conclusion, the prevalence of Pj in BAL specimens is 3.9%, which can be attributed to improved management of immunocompromised patients. Performing reflex GMS staining on all BAL specimens does not improve the diagnostic identification of Pj since the majority (98.3%) of diagnoses can be rendered on Pap stained slides. A cost analysis for GMS staining on 2,879 GMS-negative BAL specimens was estimated at $143,950. Thus, from diagnostic and cost benefit perspectives, GMS staining can be recommended only on cases where Pap stain is negative, and the clinical presentation is consistent with Pneumocystis pneumonia.


Assuntos
Lavagem Broncoalveolar/métodos , Metenamina/metabolismo , Pneumocystis carinii/citologia , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/microbiologia , Coloração pela Prata/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Rev. biol. trop ; 64(2): 913-926, abr.-jun. 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-843323

RESUMO

ResumenLa distribución de carbono azul en los ecosistemas, entre los que se cuentan los manglares, es poco conocida en comparación con los grandes avances que existen para los ecosistemas forestales terrestres, a pesar de que su alta productividad y capacidad de almacenamiento de carbono es reconocida. Este estudio, tuvo por objetivo, analizar la biomasa aérea de las especies Rhizophora mangle y Avicennia germinans en el ecosistema de manglar localizado en el área marina protegida denominada Distrito de Manejo Integrado (DMI) Cispatá-Tinajones-La Balsa en el Caribe colombiano. Para ello, con la debida autorización oficial, se cosecharon 30 individuos de cada especie, con el fin de generar modelos alométricos que permitieran estimaciones de biomasa aérea con bajos niveles de incertidumbre. Los resultados indican que la biomasa aérea de los bosques de manglar del Caribe colombiano en el DMI, es de 129.69 ± 20.24 Mg/ha, es decir, que almacenan 64.85 ± 10.12 MgC/ ha. Teniendo en cuenta que el DMI presenta un área de 8 570.9 ha en bosques de manglar, se estima que el carbono total potencialmente almacenado por este ecosistema es de aproximadamente 555 795.93 MgC. Las ecuaciones generadas en este estudio se pueden considerar como una opción alternativa para la evaluación de las reservas de carbono en la biomasa aérea de los bosques de manglar en del Caribe colombiano, dado que otros modelos disponibles para la estimación de la biomasa aérea no discriminan a los bosques de manglar, a pesar de ser ecosistemas particulares. Los modelos pueden ser empleados como una opción para apoyar las estrategias de conservación de bosques y la reducción de emisiones. En general, el potencial de almacenamiento de carbono en los bosques de manglar del Caribe colombiano, es importante, y podría posesionar al país en la conservación de bosques y la reducción de emisiones a través de la conservación del carbono azul almacenado.


AbstractThe distribution of carbon in “Blue Carbon” ecosystems such as mangroves is little known, when compared with the highly known terrestrial forests, despite its particular and recognized high productivity and carbon storage capacity. The objective of this study was to analyze the above ground biomass (AGB) of the species Rhizophora mangle and Avicennia germinans from the Marine Protected Area of Distrito de Manejo Integrado (DMI), Cispatá-Tinajones-La Balsa, Caribbean Colombian coast. With official authorization, we harvested and studied 30 individuals of each species, and built allometric models in order to estimate AGB. Our AGB results indicated that the studied mangrove forests of the DMI Colombian Caribbean was of 129.69 ± 20.24 Mg/ha, equivalent to 64.85 ± 10.12 MgC/ha. The DMI has an area of 8 570.9 ha in mangrove forests, and we estimated that the total carbon potential stored was about 555 795.93 Mg C. The equations generated in this study can be considered as an alternative for the assessment of carbon stocks in AGB of mangrove forests in Colombia; as other available AGB allometric models do not discriminate mangrove forests, despite being particular ecosystems. They can be used for analysis at a more detailed scale and are considered useful to determine the carbon storage potential of mangrove forests, as a country alternative to support forest conservation and emission reduction strategies. In general, the potential of carbon storage from Colombian Caribbean mangrove forests is important and could promote the country leadership of the “blue carbon” stored. Rev. Biol. Trop. 64 (2): 913-926. Epub 2016 June 01.


Assuntos
Carbono/análise , Florestas , Biomassa , Rhizophoraceae/metabolismo , Carbono/metabolismo , Colômbia , Região do Caribe , Rhizophoraceae/classificação , Modelos Biológicos
8.
Int J Clin Exp Pathol ; 3(4): 430-6, 2010 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-20490333

RESUMO

Mantle cell lymphoma (MCL) is a mature B-cell lymphoma characterized by expression of CD5, overexpression of Cyclin D1 as a result of chromosomal translocation t(11;14)(q13;q32), and poor prognosis. Cases of MCL lacking CD5 expression as well as cases with coexpression of CD5 and CD10 have also been reported. Here we describe an uncommon case of de novo MCL with expression of CD10, but not CD5, mimicking lymphoma of germinal center-derived B cells. The lymphoma cells in this case demonstrated a diffuse pattern of proliferation, and were strongly positive for Cyclin D1 by immunohistochemical stain. Fluorescence in situ hybridization studies demonstrated the presence of t(11;14)(q13;q32) involving BCL1, but not chromosomal translocations involving C-MYC or BCL2, confirming the diagnosis of MCL. This case further highlights the importance of comprehensive immunophenotypic and genetic characterization in the diagnosis and classification of B-cell lymphomas.


Assuntos
Antígenos CD5/biossíntese , Linfoma de Células B/patologia , Linfoma de Célula do Manto/patologia , Neprilisina/biossíntese , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 14/genética , Ciclina D1/genética , Diagnóstico Diferencial , Centro Germinativo/patologia , Humanos , Imuno-Histoquímica , Imunofenotipagem , Hibridização in Situ Fluorescente , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/metabolismo , Masculino , Pessoa de Meia-Idade , Translocação Genética
9.
Salud UNINORTE ; 30(3): 392-404, sep.-dic. 2014. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-747695

RESUMO

Objetivo: Identificar los conocimientos y prácticas sexuales en la población de adolescentes de los grados 8 a 11 de una institución educativa de la ciudad de Manizales (Caldas, Colombia). Materiales y métodos: Estudio de corte transversal; la población estuvo conformada por 170 adolescentes de 14 a 21 años, matriculados en los grados 8 a 11 de Básica Secundaria de una institución educativa de la ciudad de Manizales, de estratos medio y bajo. Se realizó por el método de encuesta. Se tomaron diferentes variables sobre conocimientos sexuales, prácticas sexuales y factores de riesgo para embarazo y enfermedades de transmisión sexual. Resultados: El promedio de edad fue de 16,31 años, de género masculino en un 56,5 %. Presentaron un promedio de 2,9 (sobre 5) de conocimientos en educación sexual, 1,8 en métodos anticonceptivos, 2,4 en embarazo, 3,5 en enfermedades de transmisión sexual, para un promedio total de 2,7. El 91,8 % ha tenido experiencias sexuales, 70,1 % con penetración; 46,6 % no emplea métodos anticonceptivos; 5 % de las mujeres manifestó que había tenido embarazos; 4,2 % dijo que no ha tenido enfermedades de transmisión sexual. El bajo puntaje de conocimientos correlaciona significativamente con incomodidad en el empleo de métodos anticonceptivos (p=0.018), desconocimiento de para qué se emplean (p=0.019), no empleo de ellos (p=0,007). Conclusiones: Debido al bajo conocimiento en temas de sexualidad y la intensa práctica sexual, esta población se convierte en población de alta riesgo para presencia de embarazos no deseados, de abortos inducidos y de enfermedades de transmisión sexual.


Objective: To identify the knowledge and the sexual practices in teen agers of 8 to 11 grade of two schools Manizales city (Caldas, Colombia). Methodology: This is a transversal retrospective study with survey application; the population were 170 teen agers between 14 and 21 years of age, who are studying from 8 to11 grades of high school of two schools Manizales city, who are in medium and low stratus. The study was done with a survey. Was use different variables about the sexual knowledge, sexual practices and risk factors about pregnancy and sexually transmitted diseases. Results: The standard of age was of 16,31 ages, the masculine genre a 56.5 %.Was an average of 2,9 (over 5) of knowledge in sexual education, 1,8 in contraceptive methods, 2,4 in pregnancy, 3,5 in sexually transmitted diseases, for an average of 2,7.The 91,8 % has had sexual experiences, 70,1 % with penetration; 46.6% do not use contraceptive methods; 5 % of the women said has had pregnancies; 4,2% said has had sexually transmitted diseases. The low score of knowledge have a significantly coincidence with the discomfort with the use of contraceptive methods (p=0.018), ignorance of which is used for (p=0.019), do not use of it. Conclusions: According to the low knowledge in sexual topics and the intense sexual practice, this population is a high risk population to have unwanted pregnancies, induced abortions and sexually transmitted diseases.

10.
Acta bioquím. clín. latinoam ; 32(4): 523-9, dic. 1998. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-236526

RESUMO

Con la intención de mejorar la precisión y sensibilidad de la medición de los anticuerpos antinucleares (ANA) por Inmunofluorescencia Indirecta, se organizó un programa de intercambio de sueros para evaluar resultados de los diferentes laboratorios de inmunología de la ciudad de Córdoba. La comparación entre los distintos participantes mostró una gran variabilidad, con diferencias de más de siete títulos para un mismo suero. En una etapa posterior, la obtención y procesamiento de un suero para ser usado como valor de referencia y la estandarización de pautas de trabajo, condujo a mejorar la sensibilidad reproducibilidad de los ANA, observándose la desaparición de valores falsos positivos y falsos negativos en los laboratorios que acataron las pautas sugeridas. El costo del programa de intercambio fue mínimo y los beneficios obtenidos fueron satisfactorios


Assuntos
Humanos , Anticorpos Antinucleares/sangue , Valores de Referência , Serviços Laboratoriais de Saúde Pública , Controle de Qualidade , Sensibilidade e Especificidade , Técnica Indireta de Fluorescência para Anticorpo/normas
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