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1.
J Endocrinol Invest ; 45(3): 497-505, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34524677

RESUMEN

PURPOSE: Polycystic Ovary Syndrome (PCOS) is the most frequent endocrinopathy in women of reproductive age. Machine learning (ML) is the area of artificial intelligence with a focus on predictive computing algorithms. We aimed to define the most relevant clinical and laboratory variables related to PCOS diagnosis, and to stratify patients into different phenotypic groups (clusters) using ML algorithms. METHODS: Variables from a database comparing 72 patients with PCOS and 73 healthy women were included. The BorutaShap method, followed by the Random Forest algorithm, was applied to prediction and clustering of PCOS. RESULTS: Among the 58 variables investigated, the algorithm selected in decreasing order of importance: lipid accumulation product (LAP); abdominal circumference; thrombin activatable fibrinolysis inhibitor (TAFI) levels; body mass index (BMI); C-reactive protein (CRP), high-density lipoprotein cholesterol (HDL-c), follicle-stimulating hormone (FSH) and insulin levels; HOMA-IR value; age; prolactin, 17-OH progesterone and triglycerides levels; and family history of diabetes mellitus in first-degree relative as the variables associated to PCOS diagnosis. The combined use of these variables by the algorithm showed an accuracy of 86% and area under the ROC curve of 97%. Next, PCOS patients were gathered into two clusters in the first, the patients had higher BMI, abdominal circumference, LAP and HOMA-IR index, as well as CRP and insulin levels compared to the other cluster. CONCLUSION: The developed algorithm could be applied to select more important clinical and biochemical variables related to PCOS and to classify into phenotypically different clusters. These results could guide more personalized and effective approaches to the treatment of PCOS.


Asunto(s)
Aprendizaje Automático , Redes y Vías Metabólicas/genética , Síndrome del Ovario Poliquístico , Servicios Preventivos de Salud , Adulto , Algoritmos , Inteligencia Artificial , Variación Biológica Poblacional , Índice de Masa Corporal , Punto Alto de Contagio de Enfermedades , Femenino , Humanos , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/diagnóstico , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Medicina de Precisión/métodos , Servicios Preventivos de Salud/métodos , Servicios Preventivos de Salud/tendencias
2.
J Dent Res ; 100(10): 1118-1126, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34315311

RESUMEN

The development of biomaterials based on the combination of biopolymers with bioactive compounds to develop delivery systems capable of modulating dentin regeneration mediated by resident cells is the goal of current biology-based strategies for regenerative dentistry. In this article, the bioactive potential of a simvastatin (SV)-releasing chitosan-calcium-hydroxide (CH-Ca) scaffold was assessed. After the incorporation of SV into CH-Ca, characterization of the scaffold was performed. Dental pulp cells (DPCs) were seeded onto scaffolds for the assessment of cytocompatibility, and odontoblastic differentiation was evaluated in a microenvironment surrounded by dentin. Thereafter, the cell-free scaffold was adapted to dentin discs positioned in artificial pulp chambers in direct contact with a 3-dimensional (3D) culture of DPCs, and the system was sealed to simulate internal pressure at 20 cm/H2O. In vivo experiments with cell-free scaffolds were performed in rats' calvaria defects. Fourier-transform infrared spectroscopy spectra proved incorporation of Ca and SV into the scaffold structure. Ca and SV were released upon immersion in a neutral environment. Viable DPCs were able to spread and proliferate on the scaffold over 14 d. Odontoblastic differentiation occurred in the DPC/scaffold constructs in contact with dentin, in which SV supplementation promoted odontoblastic marker overexpression and enhanced mineralized matrix deposition. The chemoattractant potential of the CH-Ca scaffold was improved by SV, with numerous viable and dentin sialoprotein-positive cells from the 3D culture being observed on its surface. Cells at 3D culture featured increased gene expression of odontoblastic markers in contact with the SV-enriched CH-Ca scaffold. CH-Ca-SV led to intense mineralization in vivo, presenting mineralization foci inside its structure. In conclusion, the CH-Ca-SV scaffold induces differentiation of DPCs into a highly mineralizing phenotype in the presence of dentin, creating a microenvironment capable of attracting pulp cells to its surface and inducing the overexpression of odontoblastic markers in a cell-homing strategy.


Asunto(s)
Quitosano , Animales , Calcio , Diferenciación Celular , Pulpa Dental , Dentina , Odontoblastos , Ratas , Simvastatina/farmacología
5.
Rev. bras. plantas med ; Rev. bras. plantas med;17(3): 367-373, Jul-Sep/2015. tab, graf
Artículo en Portugués | LILACS | ID: lil-752548

RESUMEN

RESUMO Estudo experimental in vitro que objetivou investigar o potencial antimicrobiano e citotóxico de quatro frações e um extrato etanólico da espécie Pouteria venosa usada como planta medicinal. A atividade antimicrobiana foi determinada pelos testes de sensibilidade microbiana, como o método de difusão em disco e o método da microdiluição em caldo, para a determinação da Concentração Inibitória Mínima (CIM). Obteve-se a avaliação da citotoxicidade por meio do método colorimétrico do Metiltetrazolium. No estudo da atividade antimicrobiana, os principais resultados foram obtidos contra Staphylococus aureus para a fração AcOEt das cascas do caule, CIM de 125 µg/mL; Streptococcus pneumoniae e Proteus mirabilis para a fração AcOEt das cascas do caule, CIMde250 µg/mL; Staphylococus epidermidis, Pseudomonas aeruginosa para a fração AcOEt das folhas e cascas do caule, CIM de 250 µg/mL. Todas as amostras foram inativas para os fungos testados. A fração AcOEt das cascas do caule foi considerada atóxica, podendo ser utilizada em testes pré-clínicos in vivo


ABSTRACT Study of antimicrobial and cytotoxic potential of Pouteria venosa species (Sapotaceae). This experimental in vitro study aimed to investigate the antimicrobial and cytotoxic potential of four fractions and one ethanolic extract of the specie Pouteria venosa used as a medicinal plant. The antimicrobial activity was determined by microbial sensitivity tests, as the method of disk diffusion and the broth microdilution method for determination of Minimum Inhibitory Concentration (MIC). The evaluation of the cytotoxicity was obtained by the Metiltetrazolium colorimetric method. In the antimicrobial activity research, the main results were obtained against the Staphylococcus aureus for the AcOEt fraction of the stem bark MIC 125 µg/mL, Streptococcus pneumoniae and Proteus mirabilis for the AcOEt fraction from the stem bark, CIM 250 µg/mL, Staphylococcus epidermidis, Pseudomonas aeruginosa to the AcOEt fraction of the leaves and stem bark, MIC 250 µg/mL. All samples did not react for the fungi tested. The AcOEt fraction of the stem bark was considered non-toxic and can be used at in vivo pre-clinical testing


Asunto(s)
Pruebas de Sensibilidad Microbiana/métodos , Citotoxinas/análisis , Pouteria/metabolismo , Antiinfecciosos/análisis , Plantas Medicinales/clasificación , Supervivencia Celular/fisiología
8.
Braz J Microbiol ; 44(2): 499-504, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24294246

RESUMEN

The therapeutic action of phosphorylated mannanoligosaccharides (MOS) was investigated regarding its prebiotic activity on enteropathogenic Escherichia coli (EPEC). Diarrhea was induced in dogs by experimental infection with EPEC strains. Then MOS was supplied once a day, in water for 20 days. Immunological (IgA and IgG), hematological (lymphocytes, neutrophils and monocytes) and bacteriological variables (PCR detection of the eae gene of EPEC recovered from stool culture), as well as occurrence of diarrhea were evaluated. All strains caused diarrhea at 24, 48 and 72 h after infection. PCR results indicated that E. coli isolated from stool culture of all infected animals had the eae gene. There was no significant difference among groups as to number of blood cells in the hemogram and IgA and IgG production. MOS was effective in recovering of EPEC-infected dogs since prebiotic-treated animals recovered more rapidly from infection than untreated ones (p < 0.05). This is an important finding since diarrhea causes intense dehydration and nutrient loss. The use of prebiotics for humans and other animals with diarrhea can be an alternative for the treatment and prophylaxis of EPEC infections.


Asunto(s)
Sangre/inmunología , Diarrea/microbiología , Escherichia coli Enteropatógena/inmunología , Heces , Fármacos Gastrointestinales/metabolismo , Oligosacáridos/metabolismo , Prebióticos , Animales , Anticuerpos Antibacterianos/sangre , Fenómenos Químicos , Modelos Animales de Enfermedad , Perros , Escherichia coli , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/química , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Leucocitos/inmunología , Oligosacáridos/administración & dosificación , Oligosacáridos/química
9.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);65(5): 1463-1471, out. 2013. tab
Artículo en Portugués | LILACS | ID: lil-689766

RESUMEN

Estudaram-se o desempenho produtivo e a viabilidade econômica no confinamento de 24 bovinos, inteiros, com idade média de 23 meses, sendo 12 Nelore (NEL) e 12 F1 Nelore x Brahman (NBR), divididos em três dietas: SIL - silagem de milho e ração concentrada; PEL - exclusiva de pellets; GRN - milho grão inteiro e pellets. O experimento foi realizado em um delineamento inteiramente ao acaso, em esquema fatorial 2x3, com quatro repetições. Os animais NBR apresentaram resultados semelhantes aos da raça NEL quanto aos desempenhos alimentar e econômico, para todas as variáveis analisadas durante o confinamento. Entre as três dietas, a dieta PEL, apesar de não ser a de maior custo em R$/kg, obteve o menor desempenho, com maior COT/kg, menor RT e menores margens líquidas. A dieta SIL apresentou os menores COT/kg e custo/kg de carcaça, com maiores receitas e margens líquidas. A dieta GRN obteve resultados econômicos semelhantes à SIL, porém obteve menor GMD em relação à SIL, além de ter o custo de dieta (R$/kg) mais oneroso em relação aos três tratamentos. Todas as dietas foram economicamente viáveis ao final do experimento, com ML/Kg de carcaça médios de 2,12, 0,35 e 1,09 para SIL, PEL e GRN, respectivamente, no entanto a dieta SIL foi a de melhor desempenho produtivo e econômico.


The production performance and economic viability of a feedlot of 24 cattle, with an average age of 23 months, 12 Nellore (NEL) and 12 F1 Nellore x Brahman (NBR), divided into three diets: SIL - corn silage and concentrate diet; PEL - exclusive of pellets; GRN - corn and whole grain pellets were studied. The experiment was conducted in a completely randomized scheme in a 2x3 factorial with four replications. The NBR animals showed similar results to the NEL in performance and economic viability for all variables analyzed. Among the diets, the PEL diet, although not the highest diet cost in R$/kg, had the lowest performance with higher TOC/kg, lower TR and lower net margins. The SIL diet had the lowest TOC/kg and cost/kg of carcass, with higher revenues and net margins. The economic results obtained for the GRN diet were similar to SIL, but had lower ADG compared to SIL and highest diet cost (R$/kg) among all. The diets were economically viable at the end of the trial, with average net margin/kg carcass of 2.12, 0.35 and 1.09 for SIL, FEP and GRN, respectively; however the SIL diet presented better productive and economical performance.


Asunto(s)
Animales , Bovinos , Bovinos/crecimiento & desarrollo , Bovinos/fisiología , Desarrollo Económico , Fenómenos Fisiológicos Nutricionales de los Animales
10.
Arq. bras. med. vet. zootec ; 65(5): 1463-1471, out. 2013. tab
Artículo en Portugués | VETINDEX | ID: vti-10053

RESUMEN

Estudaram-se o desempenho produtivo e a viabilidade econômica no confinamento de 24 bovinos, inteiros, com idade média de 23 meses, sendo 12 Nelore (NEL) e 12 F1 Nelore x Brahman (NBR), divididos em três dietas: SIL - silagem de milho e ração concentrada; PEL - exclusiva de pellets; GRN - milho grão inteiro e pellets. O experimento foi realizado em um delineamento inteiramente ao acaso, em esquema fatorial 2x3, com quatro repetições. Os animais NBR apresentaram resultados semelhantes aos da raça NEL quanto aos desempenhos alimentar e econômico, para todas as variáveis analisadas durante o confinamento. Entre as três dietas, a dieta PEL, apesar de não ser a de maior custo em R$/kg, obteve o menor desempenho, com maior COT/kg, menor RT e menores margens líquidas. A dieta SIL apresentou os menores COT/kg e custo/kg de carcaça, com maiores receitas e margens líquidas. A dieta GRN obteve resultados econômicos semelhantes à SIL, porém obteve menor GMD em relação à SIL, além de ter o custo de dieta (R$/kg) mais oneroso em relação aos três tratamentos. Todas as dietas foram economicamente viáveis ao final do experimento, com ML/Kg de carcaça médios de 2,12, 0,35 e 1,09 para SIL, PEL e GRN, respectivamente, no entanto a dieta SIL foi a de melhor desempenho produtivo e econômico.(AU)


The production performance and economic viability of a feedlot of 24 cattle, with an average age of 23 months, 12 Nellore (NEL) and 12 F1 Nellore x Brahman (NBR), divided into three diets: SIL - corn silage and concentrate diet; PEL - exclusive of pellets; GRN - corn and whole grain pellets were studied. The experiment was conducted in a completely randomized scheme in a 2x3 factorial with four replications. The NBR animals showed similar results to the NEL in performance and economic viability for all variables analyzed. Among the diets, the PEL diet, although not the highest diet cost in R$/kg, had the lowest performance with higher TOC/kg, lower TR and lower net margins. The SIL diet had the lowest TOC/kg and cost/kg of carcass, with higher revenues and net margins. The economic results obtained for the GRN diet were similar to SIL, but had lower ADG compared to SIL and highest diet cost (R$/kg) among all. The diets were economically viable at the end of the trial, with average net margin/kg carcass of 2.12, 0.35 and 1.09 for SIL, FEP and GRN, respectively; however the SIL diet presented better productive and economical performance.(AU)


Asunto(s)
Animales , Bovinos , Bovinos/crecimiento & desarrollo , Bovinos/fisiología , Desarrollo Económico , Fenómenos Fisiológicos Nutricionales de los Animales
11.
Genet Mol Res ; 12(4): 6983-95, 2013 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-24391056

RESUMEN

Endophytic microorganisms represent promising alternatives for obtaining new drugs of biotechnological importance. In this study, the endophytic species Acremonium cavaraeanum (A1a) isolated from Cocos nucifera was cultivated for the production of secondary metabolites, and its extracts and fractions were evaluated by the dilution method (MIC). The EtOAc extracts and MeOH fractions were tested against Gram-positive and -negative bacteria, and had an MIC of 125 µg/mL when evaluated in the EtOAc extract (EBI). The EtOAc extract (EBII) had an MIC of 62.25 µg/mL for Staphylococcus aureus and an MIC between 125 and 250 µg/mL for Gram-negative bacteria. The methanolic fractions showed activity with MIC between 125 and 250 µg/mL for all bacteria tested. The IGS region of the rDNA repeat unit of genomic DNA was analyzed by PCR/RFLPs, including endonucleases PstI, BamHII, HinfI, and EcoRI. The physical maps showed different restriction sites for the 6 Acremonium sp isolates, and revealed 5 RFLP patterns. The results showed that isolates of the same Acremonium species exhibited variation in this specific region. The sequences of ITS1-5.8S-ITS2 regions were aligned by Clustal W using the neighbor joining method, which grouped the isolates into 5 distinct clusters. This study aimed to evaluate the genetic diversity of A. cavaraeanum crops exhibiting antibacterial activity. The results of this study indicate that different fungal genetic isolates have biotechnological potential for the production of active bio-compounds against several human pathogens.


Asunto(s)
Acremonium/genética , ADN Espaciador Ribosómico/genética , Proteínas Fúngicas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Acremonium/aislamiento & purificación , Antibacterianos/aislamiento & purificación , Mapeo Cromosómico , Cocos/microbiología , Extracción Líquido-Líquido , Pruebas de Sensibilidad Microbiana , Polimorfismo de Longitud del Fragmento de Restricción
12.
Braz. j. microbiol ; Braz. j. microbiol;44(2): 499-504, 2013. tab
Artículo en Inglés | LILACS | ID: lil-688585

RESUMEN

The therapeutic action of phosphorylated mannanoligosaccharides (MOS) was investigated regarding its prebiotic activity on enteropathogenic Escherichia coli (EPEC). Diarrhea was induced in dogs by experimental infection with EPEC strains. Then MOS was supplied once a day, in water for 20 days. Immunological (IgA and IgG), hematological (lymphocytes, neutrophils and monocytes) and bacteriological variables (PCR detection of the eae gene of EPEC recovered from stool culture), as well as occurrence of diarrhea were evaluated. All strains caused diarrhea at 24, 48 and 72 h after infection. PCR results indicated that E. coli isolated from stool culture of all infected animals had the eae gene. There was no significant difference among groups as to number of blood cells in the hemogram and IgA and IgG production. MOS was effective in recovering of EPEC-infected dogs since prebiotic-treated animals recovered more rapidly from infection than untreated ones (p < 0.05). This is an important finding since diarrhea causes intense dehydration and nutrient loss. The use of prebiotics for humans and other animals with diarrhea can be an alternative for the treatment and prophylaxis of EPEC infections.


Asunto(s)
Animales , Perros , Sangre/inmunología , Diarrea/microbiología , Escherichia coli Enteropatógena/inmunología , Heces , Fármacos Gastrointestinales/metabolismo , Oligosacáridos/metabolismo , Prebióticos , Anticuerpos Antibacterianos/sangre , Fenómenos Químicos , Modelos Animales de Enfermedad , Escherichia coli , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/química , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Leucocitos/inmunología , Oligosacáridos/administración & dosificación , Oligosacáridos/química
13.
Braz. J. Microbiol. ; 44(2): 499-504, 2013.
Artículo en Inglés | VETINDEX | ID: vti-957

RESUMEN

The therapeutic action of phosphorylated mannanoligosaccharides (MOS) was investigated regarding its prebiotic activity on enteropathogenic Escherichia coli (EPEC). Diarrhea was induced in dogs by experimental infection with EPEC strains. Then MOS was supplied once a day, in water for 20 days. Immunological (IgA and IgG), hematological (lymphocytes, neutrophils and monocytes) and bacteriological variables (PCR detection of the eae gene of EPEC recovered from stool culture), as well as occurrence of diarrhea were evaluated. All strains caused diarrhea at 24, 48 and 72 h after infection. PCR results indicated that E. coli isolated from stool culture of all infected animals had the eae gene. There was no significant difference among groups as to number of blood cells in the hemogram and IgA and IgG production. MOS was effective in recovering of EPEC-infected dogs since prebiotic-treated animals recovered more rapidly from infection than untreated ones (p < 0.05). This is an important finding since diarrhea causes intense dehydration and nutrient loss. The use of prebiotics for humans and other animals with diarrhea can be an alternative for the treatment and prophylaxis of EPEC infections.(AU)


Asunto(s)
Perros , Bioensayo , Inmunoglobulinas , Reacción en Cadena de la Polimerasa , Escherichia coli
14.
Dis Esophagus ; 17(4): 307-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15569368

RESUMEN

Although the use of the posterior mediastinum and the stomach as a reconstruction option after esophagectomy has wide acceptance, there are concerns about the potential cardiac impairment it could cause. We prospectively studied 27 patients regarding the function and the systolic diameter, diastolic diameter, shortening fraction, ejection fraction and the presence of extrinsic compression. The patients were studied preoperatively and between the 45th and 60th postoperative days. The parameters were still within normal clinical ranges. We concluded that this type of reconstruction does not harm the patients in terms of their cardiac function.


Asunto(s)
Neoplasias Esofágicas/cirugía , Corazón/fisiopatología , Mediastino/cirugía , Procedimientos de Cirugía Plástica/efectos adversos , Estómago/cirugía , Adenocarcinoma/cirugía , Anciano , Anastomosis Quirúrgica , Carcinoma de Células Escamosas/cirugía , Diástole/fisiología , Ecocardiografía , Esofagectomía/efectos adversos , Femenino , Estudios de Seguimiento , Corazón/fisiología , Pruebas de Función Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos , Volumen Sistólico , Sístole/fisiología
15.
Dis Esophagus ; 16(3): 236-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14641316

RESUMEN

Esophagectomy is the main option for treatment of esophageal cancer. Among the subjects of surgical interest is the use of anterior versus posterior mediastinum to permit reconstruction of the alimentary tract. We performed postmortem measurements in order to analyze the lengths of both routes. For each route (anterior and posterior) we performed two measurements. The first one was called anatomical route and the second was named as surgical route. Both routes begin at the cricoid cartilage. The anatomical route goes to the celiac axis and the surgical route goes to the gastroduodenal artery. Our results show that in both routes the posterior mediastinum is a shorter way to reach the cervical region.


Asunto(s)
Esofagectomía , Mediastino/anatomía & histología , Adulto , Cadáver , Femenino , Humanos , Masculino
16.
Endocr Res ; 27(1-2): 153-69, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11428707

RESUMEN

We assessed androgen-induced cell growth and c-myc expression in human non-transformed epithelial prostatic (HNTEP) cells in primary culture. Prostatic tissue was obtained from 48 retropubic prostatectomy patients (age: 61-77years) with benign prostatic hyperplasia (malignant tumors excluded). HNTEP cells were treated with testosterone or DHT, alone or in association with hydroxyflutamide. DHT action on c-myc mRNA was examined using Northern blots and RT-PCR. RT-PCR also was used to verify if HNTEP cells expressed the androgen receptor gene. Cell proliferation was assessed on days 3 and 6. Testosterone (2 x 10(-11) M) and DHT (10(-13)M) caused a significant increase (P < 0.05) in cell proliferation on both days. Addition of hydroxyflutamide (10(-6) M) to DHT abolished cell proliferation. HNTEP cells expressed androgen receptor (AR) gene and the treatment with DHT increased AR mRNA levels. C-myc expression was maximal at 30 min and 1 h with DHT (10(-13) M). C-myc seems to play a key role in the control of hormone responsiveness and cell proliferation in epithelial prostatic cells. The detection of androgen receptor gene expression and the increase in this expression with the addition of androgen shows that the HTNEP cells maintain functional characteristics and hormone dependence, and that they are a fruitful in vitro model for studying steroid hormone action mechanisms.


Asunto(s)
Andrógenos/farmacología , División Celular/efectos de los fármacos , Flutamida/análogos & derivados , Expresión Génica/efectos de los fármacos , Próstata/citología , Próstata/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Anciano , Northern Blotting , Dihidrotestosterona/farmacología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Flutamida/farmacología , Humanos , Cinética , Masculino , Persona de Mediana Edad , Prostatectomía , Hiperplasia Prostática , ARN Mensajero/análisis , Receptores Androgénicos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Testosterona/farmacología
17.
Talanta ; 53(4): 843-50, 2001 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-18968174

RESUMEN

This paper demonstrates the application of sequential injection analysis to perform sulfide determination using the methylene blue chemistry, based on two reagents: 3.63 mmol l(-1)N,N dimethyl-p-phenylene diamine hydrochloride in 1.1 mol l(-1) HCl solution and 19 mmol l(-1) FeCl(3), also in 1.1 mol l(-1) HCl. These solutions are aspirated inside the holding coil of the sequential injection system as two reagent zones sandwiching the sample zone. Under optimized conditions, the detection limit was calculated at 40 mug l(-1) S(2-), with a linear dynamic range from 0.05 to 2 mg l(-1) S(2-). This linear range can be extended up to 32 mg l(-1) using in-line dilution for sulfide concentrations greater than 2 mg l(-1). The robust characteristic of the SI system with syringe pump leads to very stable analytical curves (precision of 4%), minimizing the laborious preparation of sulfide standards. The method was applied in the determination of acid volatile sulfide in river sediments.

18.
Antimicrob Agents Chemother ; 44(5): 1375-6, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10770783

RESUMEN

The bioavailability of didanosine at 180 mg/m(2) once daily was compared to that at 90 mg/m(2) twice daily in 24 children with advanced human immunodeficiency virus infection. Children were studied at steady state using optimal sampling and prior pharmacokinetic parameter estimates. Relative bioavailability was 0. 95 +/- 0.49, supporting the potential clinical adequacy of once-daily dosing.


Asunto(s)
Fármacos Anti-VIH/farmacocinética , Didanosina/farmacocinética , Infecciones por VIH/metabolismo , Disponibilidad Biológica , Niño , Preescolar , Humanos
19.
Dis Esophagus ; 11(1): 48-50, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9595233

RESUMEN

Although the use of the posterior mediastinum and the stomach as a reconstruction option after esophagectomy has large acceptance all over the world, there are concerns about the potential respiratory impairment it could cause. We prospectively studied 35 patients regarding the forced expiratory volume and vital capacity. The patients were studied preoperatively and between the 45th and 60th postoperative days. The value of both parameters decreased, although they were still within normal clinical ranges. We concluded that this type of reconstruction does not harm the patients regarding the respiratory flow rates.


Asunto(s)
Adenocarcinoma/cirugía , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Esofagectomía , Pruebas de Función Respiratoria , Estómago/cirugía , Anciano , Volumen Espiratorio Forzado , Humanos , Mediastino/cirugía , Persona de Mediana Edad , Periodo Posoperatorio , Estudios Prospectivos , Capacidad Vital
20.
Braz J Med Biol Res ; 30(1): 113-7, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9222412

RESUMEN

The present study was designed to assess the effects of bromocriptine, a dopamine agonist, on pituitary wet weight, number of immunoreactive prolactin cells and serum prolactin concentrations in estradiol-treated rats. Ovariectomized Wistar rats were injected subcutaneously with sunflower oil vehicle or estradiol valerate (50 or 300 micrograms/rat(-1) week (-1) for 2, 4, or 10 weeks. Bromocriptine (0.2 or 0.6 mg rat (-1) day (-1)) was injected daily during the last 5 or 12 days of estrogen treatment. Data were compared with those obtained for intact control rats. Administration of both doses of estrogen increased serum prolactin levels. No difference in the number of prolactin cells in rats treated with 50 micrograms estradiol valerate was observed compared to intact adult animals. In contrast, rats treated with 300 micrograms estradiol valerate showed a significant increase in the number of prolactin cells (P < 0.05). Therefore, the increase inn serum prolactin levels observed in rats treated with 50 micrograms estradiol valerate, in the absence of morphological changes in the pituitary cells, suggests a "functional" estrogen-induced hyperprolactinemia. Bromocriptine decreased prolactin levels in all estrogen-treated rats. The administration of this drug to rats previously treated with 300 micrograms estradiol valerate also resulted in a significant decrease in pituitary weight and number of prolactin cells when compared to the group treated with estradiol alone. The general antiprolactinemic and antiproliferative pituitary effects of bromocriptine treatment reported here validate the experimental model of estrogen-induced hyperprolactinemic rats.


Asunto(s)
Bromocriptina/farmacología , Hiperprolactinemia/inducido químicamente , Ovariectomía , Hipófisis/efectos de los fármacos , Hipófisis/patología , Prolactina/sangre , Prolactina/efectos de los fármacos , Animales , Estradiol/administración & dosificación , Femenino , Tamaño de los Órganos , Ratas , Ratas Wistar
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