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1.
Addit Manuf ; 842024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38567361

RESUMO

The working curve informs resin properties and print parameters for stereolithography, digital light processing, and other photopolymer additive manufacturing (PAM) technologies. First demonstrated in 1992, the working curve measurement of cure depth vs radiant exposure of light is now a foundational measurement in the field of PAM. Despite its widespread use in industry and academia, there is no formal method or procedure for performing the working curve measurement, raising questions about the utility of reported working curve parameters. Here, an interlaboratory study (ILS) is described in which 24 individual laboratories performed a working curve measurement on an aliquot from a single batch of PAM resin. The ILS reveals that there is enormous scatter in the working curve data and the key fit parameters derived from it. The measured depth of light penetration Dp varied by as much as 7x between participants, while the critical radiant exposure for gelation Ec varied by as much as 70x. This significant scatter is attributed to a lack of common procedure, variation in light engines, epistemic uncertainties from the Jacobs equation, and the use of measurement tools with insufficient precision. The ILS findings highlight an urgent need for procedural standardization and better hardware characterization in this rapidly growing field.

2.
Front Med (Lausanne) ; 10: 1236702, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37727759

RESUMO

Introduction: Few studies have evaluated the presence of Post COVID-19 conditions (PCC) in people from Latin America, a region that has been heavily afflicted by the COVID-19 pandemic. In this study, we describe the frequency, co-occurrence, predictors, and duration of 23 symptoms in a cohort of Mexican patients with PCC. Methods: We prospectively enrolled and followed adult patients hospitalized for severe COVID-19 at a tertiary care centre in Mexico City. The incidence of PCC symptoms was determined using questionnaires. Unsupervised clustering of PCC symptom co-occurrence and Kaplan-Meier analyses of symptom persistence were performed. The effect of baseline clinical characteristics was evaluated using Cox regression models and reported with hazard ratios (HR). Results: We found that amongst 192 patients with PCC, respiratory problems were the most prevalent and commonly co-occurred with functional activity impairment. 56% had ≥5 persistent symptoms. Symptom persistence probability at 360 days 0.78. Prior SARS-CoV-2 vaccination and infection during the Delta variant wave were associated with a shorter duration of PCC. Male sex was associated with a shorter duration of functional activity impairment and respiratory symptoms. Hypertension and diabetes were associated with a longer duration of functional impairment. Previous vaccination accelerated PCC recovery. Discussion: In our cohort, PCC symptoms were frequent (particularly respiratory and neurocognitive ones) and persistent. Importantly, prior SARS-CoV-2 vaccination resulted in a shorter duration of PCC.

3.
Cir Cir ; 90(S1): 15-24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35944119

RESUMO

OBJECTIVE: To evaluate efficacy and safety between dual angiotherapy (endocoil plus N-butyl-cyanoacrylate) guided by endoscopic ultrasound) versus N-butyl-cyanoacrylate in the secondary prophylaxis of gastroesophageal varices (GOV). METHOD: Prospective non-inferiority study comparing two gastric variceal eradication techniques. We evaluated technical and clinical success, GOV occlusion and eradication, rebleeding, reoperation, GOV-free period, complications, and mortality. Chi square for categorical variables and Student's t for numerical variables with a significance level of 0.05. RESULTS: There were 68 patients (average age 55.5 ± 10 years, women 44 (64.7%) and average body mass index 25.7 ± 3.5 kg/m2). The most frequent cause was alcoholic steatohepatitis (58%). Dual therapy had greater technical (100% vs. 94.3%) and clinical (100% vs. 85%) success. Obliteration was faster (100 vs. 79.2%). This group only required one session. The GOV size was 24 ± 14 mm and 1-2 endocoils were placed. The median follow-up was 221 days. The reoperation-free rate was high (100% vs. 94%; p = 0.9). CONCLUSIONS: Dual angiotherapy guided by endoscopic ultrasound and cyanoacrylate injection are effective for the eradication of GOV without differences in adverse event rates.


OBJETIVO: Evaluar la eficacia y la seguridad de la angioterapia dual (endo-coil más N-butil-cianoacrilato) guiada por ultrasonido endoscópico) frente a N-butil-cianoacrilato solo en la profilaxis secundaria de várices gásctricas. MÉTODO: Estudio prospectivo de no inferioridad comparando dos técnicas de erradicación de várices gástricas. Se evalúan el éxito técnico y clínico, la oclusión y la erradicación de GOV, el resangrado, la reintervención, el período libre de GOV, las complicaciones y la mortalidad. Análisis estadístico mediante prueba de χ2 para variables categóricas y t de Student para las numéricas, con nivel de significancia de 0.05. RESULTADOS: Fueron 68 pacientes (edad promedio 55.5 ± 10 años, mujeres 44 (64.7%) e índice de masa corporal promedio 25.7 ± 3.5 kg/m2). La causa más frecuente fue esteatohepatitis alcohólica (58%). La terapia dual tuvo mayor éxito técnico (100% vs. 94.3%) y clínico (100% vs. 85%), y la obliteración fue más rápida (100 vs. 79.2%); este grupo solo requirió una sesión. El tamaño de las GOV fue de 24 ± 14 mm y se colocaron uno o dos endo-coils. La mediana de seguimiento fue de 221 días. La tasa de libres de reintervención fue alta (100% vs. 94%; p = 0.9). CONCLUSIONES: La angioterapia dual guiada por ultrasonido y la inyección de cianoacrilato son efectivas para la erradicación de las GOV, sin diferencias en las tasas de eventos adversos.


Assuntos
Embucrilato , Varizes Esofágicas e Gástricas , Idoso , Embucrilato/efeitos adversos , Embucrilato/uso terapêutico , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/terapia , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção
4.
Ann Pediatr Cardiol ; 13(3): 256-259, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32863666

RESUMO

Extraintestinal manifestations are common complications of inflammatory bowel disease (IBD), whereas the recurrent pericarditis during remission of Crohn's disease is rarely reported. Chest pain developed in a 13-year-old adolescent male who had a history of Crohn's colitis since 9 years of age and was in remission for 4 years after treatment with infliximab, adalimumab, and vedolizumab. Physicians should be aware of the pericardial involvement in patients with a history of IBD. The literature on pericardial involvement in Crohn's disease is reviewed with emphasis on the management of recurrent pericardial effusion in the pediatric age group.

5.
J Mol Model ; 26(2): 33, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31982975

RESUMO

The non-dissociative and dissociative adsorptions of zwitterionic Gly on graphene oxide (GO) was studied in the framework of DFT using a cluster model approach. In this work, the interaction with an epoxy group of GO basal plane was mainly considered. As a comparison, the non-dissociative and dissociative adsorptions of neutral Gly were also taken into account. The non-dissociative adsorption modes for zwitterionic and neutral Gly conformers show binding energies of 12.2 and 14.4 kcal mol-1, respectively. These molecules are thought to remain over the GO surface due to attractive noncovalent interactions. Two dissociative adsorption modes, for Z-Gly and N-Gly, show smaller binding energies of 7.2 and 8.4 kcal mol-1, where the deprotonated species links strongly through a C-O or C-N covalent bond to the GO surface. The results obtained in the present theoretical approach to the glycine/graphene oxide system support the fact that glycine can be attached to epoxy groups of graphene oxide basal planes in addition to the anchoring on edge oxidation groups. In summary, we conclude that glycine can be used as a reducing agent as well as a functionalizer of GO sheets.


Assuntos
Glicina/química , Grafite/química , Modelos Químicos , Adsorção
6.
Emerg Infect Dis ; 25(7)2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31211679

RESUMO

Candida auris is an emerging multidrug-resistant fungus that causes hospital-associated outbreaks of invasive infections with high death rates. During 2015-2016, health authorities in Colombia detected an outbreak of C. auris. We conducted an investigation to characterize the epidemiology, transmission mechanisms, and reservoirs of this organism. We investigated 4 hospitals with confirmed cases of C. auris candidemia in 3 cities in Colombia. We abstracted medical records and collected swabs from contemporaneously hospitalized patients to assess for skin colonization. We identified 40 cases; median patient age was 23 years (IQR 4 months-56 years). Twelve (30%) patients were <1 year of age, and 24 (60%) were male. The 30-day mortality was 43%. Cases clustered in time and location; axilla and groin were the most commonly colonized sites. Temporal and spatial clustering of cases and skin colonization suggest person-to-person transmission of C. auris. These cases highlight the importance of adherence to infection control recommendations.


Assuntos
Candida , Candidíase/epidemiologia , Candidíase/microbiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/microbiologia , Infecção Hospitalar , Surtos de Doenças , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candidemia/epidemiologia , Candidemia/microbiologia , Candidíase/tratamento farmacológico , Candidíase/história , Criança , Pré-Escolar , Colômbia/epidemiologia , Doenças Transmissíveis Emergentes/história , Farmacorresistência Fúngica , Feminino , História do Século XXI , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mortalidade , Avaliação de Resultados da Assistência ao Paciente , Vigilância em Saúde Pública , Estações do Ano , Adulto Jovem
7.
Protoplasma ; 256(4): 1079-1092, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30923921

RESUMO

Calcium is a secondary messenger that regulates and coordinates the cellular responses to environmental cues. Despite calcium being a key player during fertilization in plants, little is known about its role during the development of the endosperm. For this reason, the distribution, abundance, and dynamics of cytosolic calcium during the first stages of endosperm development of Agave tequilana and Agave salmiana were analyzed. Cytosolic calcium and actin filaments detected in the embryo sacs of Agave tequilana and A. salmiana revealed that they play an important role during the division and nuclear migration of the endosperm. After fertilization, a relatively high concentration of cytosolic calcium was located in the primary nucleus of the endosperm, as well as around migrating nuclei during the development of the endosperm. Cytosolic calcium participates actively during the first mitosis of the endosperm mother cell and interacts with the actin filaments that generate the motor forces during the migration of the nuclei through the large cytoplasm of the central cell.


Assuntos
Agave/crescimento & desenvolvimento , Cálcio/metabolismo , Citosol/metabolismo , Endosperma/crescimento & desenvolvimento , Citoesqueleto de Actina/metabolismo , Agave/citologia , Agave/metabolismo , Endosperma/citologia , Endosperma/metabolismo , Mitose , Células Vegetais/metabolismo
8.
J Mol Model ; 25(1): 16, 2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30610386

RESUMO

A computational DFT study of the reaction mechanism of hydrogenation and hydration of carbon dioxide is presented. It has been found that hydrogenation and hydration are endoenergetic reactions that are carried out in two steps, passing by a stable intermediate that is surrounded by energy barriers of 70 kcal/mol and 10 kcal/mol for hydrogenation and 50 kcal/mol and 10 kcal/mol for hydration. Using the reaction force analysis, we were able to characterize the physical nature of the activation barriers and found that activation energies are mostly due to structural rearrangements. An interesting difference in the reaction mechanisms disclosed by the reaction force and electronic flux analyses is that while in the hydrogenation reaction the mechanisms is conditioned by the H2 cleavage with a high energy barrier, in the hydration reaction the formation of a transient four member ring structure favoring an attractive local hydrogen bond interaction pushes the reaction toward the product with a considerably lower energy barrier.

9.
Eur J Med Chem ; 60: 350-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23314048

RESUMO

As a part of our research in the chemistry of chalcones we have prepared four pyrimidine monoadducts of bis-chalcones through the reaction with 6-amino-1,3-dimethyl uracil. These compounds displayed cytotoxicity with a massive vacuolation in different human cell lines in vitro. Compound 6 was the most cytotoxic inducer of vacuoles, this compound induced G1 phase cell cycle arrest, and their cytotoxicity went without morphological and biochemical evidence of apoptotic cell death in HeLa cells. In addition, our results showed that this vacuole formation does not require de novo protein synthesis and the content vacuolar is acidic. Compound 6 induce necrotic cell death with excessive vacuolation, similar to a process of autophagy. Spautin-1 an inhibitor of autophagy, decreased the transformation of microtubule-associated protein 1 light chain 3 (LC3B-I) to LC3B-II and the vacuolation induced by compound 6 in HeLa cells, both autophagy processes. These compounds could be of pivotal importance in the study of non-apoptotic cell death with vacuole formation and could be useful in research into new autophagy inhibitors agents.


Assuntos
Antineoplásicos/farmacologia , Chalconas/farmacologia , Uracila/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chalconas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Uracila/química , Uracila/farmacologia
10.
Eur J Med Chem ; 45(3): 1211-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20045224

RESUMO

A series of 6-substituted 2-(N-trifluoroacetylamino)imidazopyridines have been synthesized and their bioactivities were evaluated. Compounds 6a, 6c, and 11a were the most active compounds with modest cytotoxic activity against six human cancer cell lines U251 (glioma), PC-3 (prostate), K-562 (leukemia), HCT-15 (colon), MCF7 (breast) and SK-LU-1 (lung). The cell cycle analysis showed that compounds 6a, 6c, and 11a induce a G2/M phase cell cycle arrest on SK-LU-1 cell line where inhibition of CDK-1 and CDK-2 may be implicated.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Flúor/química , Imidazóis/farmacologia , Piridinas/farmacologia , Proteína Quinase CDC2/metabolismo , Linhagem Celular Tumoral , Humanos , Imidazóis/síntese química , Imidazóis/química , Neoplasias Pulmonares/tratamento farmacológico , Estrutura Molecular , Piridinas/síntese química , Piridinas/química
11.
Eur J Med Chem ; 45(1): 379-86, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19879023

RESUMO

A series of 2-methylimidazo[1,2-a]pyridine- and quinoline-substituted 2-aminopyrimidines derivatives were synthesized using a convenient synthetic route. We evaluate the isosteric replacement of methyl groups in 4-(2-methylimidazo[1,2-a]pyridin-3-yl)-N-p-tolylpyrimidin-2-amine (compound 1) by trifluoromethyl groups and the isosteric substitution of the 2-methylimidazo[1,2-a]pyridin-3-yl scaffold by quinolin-4-yl or quinolin-3-yl moieties. The replacement of hydrogen by fluorine does not affect notably the cytotoxic activity and CDK inhibitor activity in this series. Quinolin-4-yl-substituted compound, 8, presents cytotoxic activity and is most effective and selective against CDK1/CycA than against CDK2/CycB. Compound 11, which has a quinolin-3-yl moiety is CDK inhibitor but presents null cytotoxic activity. Quinolin-4-yl-substituted compounds constitute a new lead of cytotoxic and CDK inhibitor compounds from which more compelling and selective inhibitors can be designed.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Piridinas/química , Pirimidinas/química , Pirimidinas/farmacologia , Quinolinas/química , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quinases Ciclina-Dependentes/antagonistas & inibidores , Humanos , Concentração Inibidora 50 , Pirimidinas/síntese química
12.
Gac Med Mex ; 141(6): 501-4, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16381505

RESUMO

OBJECTIVE: To determine if short term exclusive (EBF), combined breastfeeding (CBF), or an early start of other kind of food constitute risk factors for appendicitis in children. MATERIALS AND METHODS: By means of a case-control study, the mothers of 200 children up to 16 years with a diagnosis of acute appendicitis and 200 matched controls were interviewed regarding the duration of breastfeeding and the start of other foods. Data were analyzed to calculate chi-square c2; odds ratio (OR) was used to calculate risk factors, confidence intervals (CI 95%) were also determined. RESULTS: There was no EBF in 52 cases (26%), or in 5 controls (2.5%) (p< 0.001). EBF lasted for 2.3 +/- 1.8 months in cases and 3 +/- 1.1 months in controls (p< 0.001). CBF lasted for 8.1 +/- 7.5 months in cases and 8.8 +/- 3.5 in controls (p< 0.001); ablactation was started at 4.4 +/- 1.3 months in cases and at 4.7+/-1.2 in controls (p< 0.05). The OR of developing appendicitis for non- EBF was 10.4 (CI 95% 4 - 26.5), for ablactation before 4 months 1.4, (CI 95% 0.9 - 2) and for CBF for less than 6 months 4.6, (CI 95% 2.3 - 8.3). CONCLUSIONS: The risk of developing appendicitis is higher among children who never received EBF and who were breastfed for less than 6 months.


Assuntos
Apendicite/etiologia , Aleitamento Materno , Adolescente , Apendicite/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores de Risco , Fatores de Tempo
13.
Gac. méd. Méx ; 141(6): 501-504, nov.-dic. 2005. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-632139

RESUMO

Objetivo: Determinar si un régimen de alimentación al seno materno exclusiva (ASME) o combinada (ASMT) de corta duración, o una temprana ablactación constituyen factores de riesgo para desarrollar apendicitis aguda en la niñez. Material y métodos: Mediante un estudio de casos y controles se interrogó a las madres de 200 menores de edad preescolar, escolar y adolescente con diagnóstico de apendicitis aguda y de 200 controles pareados acerca de la duración de la alimentación al seno materno y la edad al inicio de fórmulas o papillas. Los datos fueron analizados mediante la prueba x², razón de momios (RM) e intervalos de confianza (IC 95%). Resultados: En 52 casos (26%), 5 controles no recibieron ASME (2.5%) (p< 0.001). La ASME se prolongó durante 2.3 ± 1.8 meses en los casos y 3 ± 1.1 meses en los controles (p< 0.001), y la ASMT durante 8.1 ± 7.5 meses en los casos y 8.8 ± 3.5 en los controles (p< 0.001); la ablactación ocurrió a los 4.4 ± 1.3 meses en los casos y 4.7 ± 1.2 en los controles (p< 0.05). El riesgo de padecer apendicitis para el que nunca recibió ASME fue de 10.4 (IC 95% 4 -26.5), para la ablactación antes de los 4 meses de 1.4, (IC 95% 0.9 - 2) y para la alimentación al seno materno menor a 6 meses de duración de 4.6, (IC 95% 2.3 8.3). Conclusiones: El riesgo de padecer apendicitis aumenta en los niños que no recibieron ASME y en los que recibieron ASMT por menos de seis meses.


Objective: To determine if short term exclusive (EBF), combined breastfeeding (CBF), or an early start of other kind of food constitute risk factors for appendicitis in children. Materials and methods: By means of a case control study, the mothers of 200 children up to 16 years with a diagnosis of acute appendicitis and 200 matched controls were interviewed regarding the duration of breastfeeding and the start of other foods. Data were analyzed to calculate chi square c²; odds ratio (OR) was used to calculate risk factors, confidence intervals (CI 95%) were also determined. Results: There was no EBF in 52 cases (26%), or in 5 controls (2.5%) (p< 0.001). EBF lasted for 2.3 ± 1.8 months in cases and 3 ± 1.1 months in controls (p< 0.001). CBF lasted for 8.1 ± 7.5 months in cases and 8.8 ± 3.5 in controls (p< 0.001); ablactation was started at 4.4 ± 1.3 months in cases and at 4.7 ± 1.2 in controls (p< 0.05). The OR of developing appendicitis for non- EBF was 10.4 (CI 95% 4 -26.5), for ablactation before 4 months 1.4, (CI 95% 0.9 - 2) and for CBF for less than 6 months 4.6, (CI 95% 2.3 8.3). Conclusions: The risk of developing appendicitis is higher among children who never received EBF and who were breastfed for less than 6 months.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Apendicite/etiologia , Aleitamento Materno , Apendicite/epidemiologia , Estudos de Casos e Controles , Fatores de Risco , Fatores de Tempo
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(11-12): 2788-95, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16043079

RESUMO

A series of novel isoindolone derivatives (13-18) were prepared in goods yields by applying the TAWERS methodology. A general approach for formation of isoindolones from the aza-Wittig reaction of iminophosphoranes with dialdehydes under neutral and mild conditions was realized. Using 1D NMR a [1,3]-hydride migration was detected. The assignment of the structures and conformation behavior of the derivatives was achieved using 1D and 2D NMR (NOESY, DEPT, HMQC, and HMBC).


Assuntos
Indóis/química , Indóis/síntese química , Isomerismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Prótons
15.
J Clin Periodontol ; 31(8): 625-32, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15257739

RESUMO

OBJECTIVES: The objective of this study was to determine if an association existed between periodontal disease and various systemic medical conditions and tobacco use. MATERIAL AND METHODS: The study design was a case-controlled, retrospective chart review. Patient charts (n=2006) were selected from more than 13,000 active patients attending the University of Minnesota dental clinics. These charts were examined to determine patient's self-reported systemic condition and smoking history. In addition, the number of missing teeth and bone loss were recorded. Two examiners collected the data. One examiner abstracted patient's medical history from the standard clinic medical questionnaire. The second examiner assessed the radiographs and dental charts to determine bone loss and number of missing teeth. Each examiner was blind to the findings of the other. RESULTS: After adjusting for age, sex, diabetes and smoking (yes/no) status, seven conditions were significantly (p=0.0003-0.04) related to bone loss or number of missing teeth (vascular disease, heart surgery, vascular surgery, heart attack, thyroid problems, arthritis, stomach ulcers). From these conditions, thyroid problems and arthritis had a negative association with bone loss. CONCLUSIONS: These findings support the results from previous investigators that a number of systemic conditions and smoking are closely associated with missing teeth or bone loss.


Assuntos
Doenças Periodontais/complicações , Tabagismo/complicações , Idoso , Idoso de 80 Anos ou mais , Artrite/complicações , Doenças Cardiovasculares/complicações , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Doenças Periodontais/etiologia , Estudos Retrospectivos , Fatores de Risco , Úlcera Gástrica/complicações , Doenças da Glândula Tireoide/complicações , Perda de Dente/complicações
16.
Vitae (Medellín) ; 9(1): 51-57, sept. 2001-mar. 2002. graf
Artigo em Espanhol | LILACS | ID: lil-353609

RESUMO

Durante muchos siglos la gente ha usado plantas con propiedades medicinales para el tratamiento de diversas enfermedades. Una de estas enfermedades es diabetes mellitus. Una de las plantas usadas ampliamente por la población en Puerto Rico es Costus speciosus conocida vulgarmente como insulina. El objetivo principal de este estudio fue analizar las propiedades hipoglicemiantes que se le atribuyen al extracto de esta planta. Con estos fines se llevaron a cabo experimentos con ratas Sprague Dawley, a las cuales se les había inducido diabetes por medio de la inyección de estreptozotocina i.p. A un grupo de diez de estas ratas en ayunas (Grupo A) se le dio a tomar el extracto por 24 horas, mientras que a otro grupo testigo de diez ratas (grupo B) se le administró agua. El grupo A tuvo niveles de glucosa sanguínea significativamente inferiores a las ratas del grupo testigo. En otro experimento se incubaron células endoteliales con o sin el extracto de la planta en presencia de 2-desoxi-3H-glucosa (DG). Hubo una mayor captación de DG en las células que contenían el extracto de la planta. Esto indica que el extracto contiene algún o algunos compuestos que facilitan la entrada de glucosa a las células cuya acción es similar a la de insulina. En los ensayos de toxicidad general usando Artemia salina L., el valor CL50 18.45 :g/mL demuestra la presencia de uno o varios agentes farmacológicamente activos en el extracto. En conclusión, el extracto de Costus speciosus muestra un efecto hipoglicemiante en ratas diabéticas inducidas con estreptozotocina. Además, el extracto de esta planta estimula la captación de DG en las células endoteliales


Assuntos
Plantas Medicinais , Diabetes Mellitus , Insulina
17.
Rev. méd. Hosp. Gen. Méx ; 62(2): 121-7, abr.-jun. 1999. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-266174

RESUMO

Se describe la frecuencia de la coledocolitiasis y se analizan las diferentes opciones terapéuticas disponibles. Desde el punto de vista no quirúrgico, son descritas en general las tecnicas, su frecuencia de éxito y complicaciones, así como las ventajas principales para la colangiopancreatografía retrograda endoscópica convencional, la litotripsia mecánica, electrohidráulica y con rayo láser se menciona la utilidad de la litotripsia extracospórea, la colocación de prótesis endobiliares y el manejo disolutivo con mono-octanoína. En el paciente posoperado y con presencia de sonda en T en el colédoco, resulta de gran utilidad el abordaje radiológico intervencionista. Por otro lado, las opciones quirúrgicas se han enriquecido con la cirugía laparoscópica o de invasión mínima, cuyo desarrollo ofrece una exploración transoperatoria tan eficaz como la de la cirugía abierta. Finalmente, se discute la elección de alguna opción dependiendo de factores como la edad, el sexo, etcétera


Assuntos
Humanos , Litotripsia , Litotripsia/instrumentação , Colangiografia , Cálculos Biliares/diagnóstico , Cálculos Biliares , Cálculos Biliares/terapia , Laparoscopia
18.
P. R. health sci. j ; 17(4): 359-64, Dec. 1998. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-234850

RESUMO

OBJECTIVES: This study was conducted to search for xanthine oxidase inhibitors in natural products obtained from plants collected in Puerto Rico and to assess the influence of these extracts in the prevention of cataractogenesis. BACKGROUND: Allopurinol is currently a xanthine oxidase inhibitor used in the treatment of gout. New alternatives with increased therapeutic activity and less side effects should be investigated. Preclusion of cataractogenesis in diabetic rats is also the focus of this investigation. Natural products in the form of plant extracts from Puerto Rico offer a rich and relatively untapped source for the discovery of new drugs that may address these kind of problems. METHODS: Nineteen collections of Myrtaceae plant extracts were screened for xanthine oxidase inhibition. A spectrophotometrical method was used employing allopurinol as positive control and a blank as negative control. A protocol of the assay with slight modifications was followed from the literature. Two extracts with the highest percentages of xanthine oxidase inhibition were evaluated for possible prevention of cataractogenesis in streptozotocin diabetic rats. The animals were given to drink these plant extracts ad libitum for three months while controls received water. The appearance of cataracts was assessed physically. RESULTS: Two of the nineteen plant extracts showed high inhibition percentages of xanthine oxidase. Eucalyptus deglupta and Syzygium malaccense displayed 51 per cent and 64 per cent inhibitions (IC50 44.5 micrograms/ml and IC50 51 micrograms/ml), respectively. As for the cataractogenesis inhibition, laboratory animals that drank E. deglupta for three months did not develop cataracts. CONCLUSIONS: Two plant extracts provided positive results with varying degrees of inhibition of xanthine oxidase. S. malaccense demonstrated the greatest xanthine oxidase inhibitory activity whereas E. deglupta presented the best finding for cataractogenesis prevention. The procedures used in this investigation are useful for the in vitro screening of xanthine oxidase inhibition and the in vivo evaluation of cataractogenesis prevention.


Assuntos
Animais , Ratos , Catarata/prevenção & controle , Medicina Tradicional , Extratos Vegetais/farmacologia , Plantas Medicinais , Xantina Oxidase/antagonistas & inibidores , Alopurinol/farmacologia , Diabetes Mellitus Experimental/complicações , Eucalyptus , Inibidores Enzimáticos/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/uso terapêutico , Porto Rico , Ratos Sprague-Dawley , Espectrofotometria
19.
Endoscopia (México) ; 9(4): 159-62, oct.-dic. 1998. ilus
Artigo em Espanhol | LILACS | ID: lil-248149

RESUMO

La hemorragia de tubo digestivo alto secundaria a várices esofágicas ocupa el primer lugar como causa en el servicio de urgencia en el Hospital General de México O.D. La escleroterapia ha demostrado ser un método de tratamiento seguro y eficaz, pero no libre de complicaciones. Ante la existencia de una nueva modalidad de tratamiento como es la ligadura con bandas de látex, informamos de nuestras primeras experiencias con este método, las expectativas del mismo, así como las modificaciones caseras en los aplicadores de ligas comerciales realizados en la Unidad de Endoscopia del Servicio de Urgencias, con el que se logró acceder a este método en nuestro medio


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Ligadura , Ligadura/instrumentação , Escleroterapia , Escleroterapia/instrumentação , Varizes Esofágicas e Gástricas/terapia
20.
Acta cancerol ; 28(2): 26-32, nov. 1998. tab, graf
Artigo em Espanhol | LILACS, LIPECS | ID: lil-267218

RESUMO

Objetivo: determinar el valor predictivo positivo del CA-125, ultrasonografía pélvica y estado menopáusico, y la asociación de éstos como predictores de malignidad ovárica. Material y Métodos: Estudio transversal, descriptivo y prospectivo efectuado en el Hospital Guillermo Almenara (julio-diciembre 1996). Se evalúan pacientes con diagnóstico preoperatorio de tumor ovárico y se determinan el indice morfológico (IM) de la Universidad de Kentucky (menor o mayor 5), el CA-125 sérico (menor 0 mayor 35 U/ml), la edad (menor 0 mayor 48a) y el diagnóstico histológico de los tumores pélvicos. Resultados: Se registraron 86 casos (63 benignos y 23 malignos) predominando los tumores serosos. El VPP fue 0.426 para el IM, 0.615 para el CA-125, 0889 para asociación IM mas CA-125, y cuando además se asoció el estado menopáusico, IM+CA-125+Em, el VPP fue 1.000. Discusión: Los tumores ováricos con IM menor 5 fueron y aquellos con IM mayor 5 sólo 42.6 por ciento fueron malignos (VPP:0.426). El VPP del CA-125 mejoró cuando éste se asoció al IM: 0.889. El estado menopáusico (edad) mejora aún más su valor predictivo. Conclusiones: 1. El IM tuvo un VPP menor que el del CA-125. 2. Con la asociación de éstos se mejora el VPP (se disminuye la tasa de falsos positivos). 3. La asociación IM+CA-125+EM optimiza el VPP alcanzando el 100 por ciento permitiendo diferenciar los tumores ováricos benignos. 4. Los predictores de malignidad ovárica son óptimos cuando éstos se asocian.


Assuntos
Humanos , Masculino , Feminino , Adulto , Adolescente , Pessoa de Meia-Idade , Neoplasias Ovarianas , Menopausa , Ultrassonografia , Estudos Transversais , Estudos Prospectivos , Epidemiologia Descritiva
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