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1.
J Ethnopharmacol ; 195: 238-245, 2017 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-27864111

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Tetracera potatoria Afzel. Exg. Don (Dilleniaceae) is a medicinal plant used traditionally in Africa for the treatment of tuberculosis related ailments and respiratory infections. The antibacterial activity of the medium polar extracts of T. potatoria leaves and stem bark was recently reported against Mycobacterium smegmatis (MIC 25µg/mL) and M. aurum (65µg/mL), two fast-growing Mycobacterium strains used as model micro-organisms for the more pathogenic strain Mycobacterium tuberculosis (Fomogne-Fodjo et al., 2014). The aim of this study was consequently to isolate the compounds possibly contributing to this activity, and which may therefore be promising precursors to be used for the development of novel anti-TB drugs. MATERIALS AND METHODS: T. potatoria medium polar extract [MeOH/DCM (1:1, v/v)] was fractionated sequentially with petroleum ether to which EtOAC and MeOH were gradually added to increase the polarity. The examination of T. potatoria extract and its fractions was guided by bioassays for anti-mycobacterial activity against M. smegmatis (ATCC 23246) and M. aurum (NCTC 10437) using the minimum inhibitory concentration (MIC) method. All the isolated compounds were structurally elucidated using spectroscopic techniques and evaluated for their anti-mycobacterial activity. RESULTS: Two novel secondary metabolites (1, 2) named tetraceranoate and N-hydroxy imidate-tetracerane, together with five known compounds [ß-stigmasterol (3), stigmast-5-en-3ß-yl acetate (4), betulinic acid (5), betulin (6) and lupeol (7)] were isolated and identified. Tetraceranoate exhibited the best activity against M. smegmatis with a minimum inhibitory concentration (MIC) of 7.8µg/mL, while ß-stigmasterol, betulinic acid and betulin showed appreciable anti-mycobacterial activity against both strains (MIC 15µg/mL). CONCLUSION: Seven compounds were isolated from the medium polar extract [MeOH/DCM (1:1, v/v)] of T. potatoria stem bark. Only tetraceranoate one of the isolated compounds showed antibacterial activity against M. smegmatis having efficacy as high as rifampicin (one of a three drug regimen recommended in the initial phase short-course anti-tuberculosis therapy). Thus, tetraceranoate might be an interesting target for systematic testing of anti-TB treatment and management. This research supports the use of T. potatoria in African traditional medicine for the treatment of tuberculosis related symptoms.


Asunto(s)
Antituberculosos/farmacología , Dilleniaceae/metabolismo , Mycobacterium smegmatis/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Corteza de la Planta/metabolismo , Tallos de la Planta/metabolismo , Antituberculosos/química , Antituberculosos/aislamiento & purificación , Fraccionamiento Químico , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium smegmatis/crecimiento & desarrollo , Mycobacterium tuberculosis/crecimiento & desarrollo , Fitoterapia , Plantas Medicinales , Rifampin/farmacología , Solventes/química , Relación Estructura-Actividad
2.
J Ethnopharmacol ; 179: 76-82, 2016 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-26724423

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves, stems and roots of Alchornea cordifolia (Schumach. and Thonn.) Müll. Arg. are used as traditional medicine in many African countries for the management of gastrointestinal, respiratory and urinary tract infections as well as for the treatment of wounds. AIM OF THE STUDY: To determine the in vitro antibacterial activity of the crude extracts of leaves and stems of A. cordifolia on gastrointestinal, skin, respiratory and urinary tract pathogens and to identify the compounds in the extracts that may be responsible for this activity. MATERIALS AND METHODS: The antibacterial activities of crude extracts [hexane, chloroform (CHCl3), ethyl acetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O)] as well as pure compounds isolated from these extracts were evaluated by means of the micro-dilution assay against four Gram-positive bacteria, i.e. Bacillus cereus ATCC 11778, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923 and S. saprophyticus ATCC 15305, as well as four Gram-negative bacterial strains, i.e. Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 13883, Moraxella catarrhalis ATCC 23246 and Proteus mirabilis ATCC 43071. The isolation of the active constituents was undertaken by bio-autographic assays in conjunction with chromatographic techniques. The identification and characterisation of the isolated compounds were done using mass spectrometry (MS) and Fourier transformed infrared spectrometry (FTIR) as well as 1D- and 2D- nuclear magnetic resonance (NMR) analyses. RESULTS: The leaves and stems of A. cordifolia exhibited varied antibacterial activity against all eight pathogens. Most of the MIC values ranged between 63 and 2000µg/ml. The highest activities for the crude extracts (63µg/ml) were observed against S. saprophyticus [stem (EtOAc, CHCl3 and hexane), leaves (MeOH, EtOH, EtOAc and CHCl3)], E. coli [stem (MeOH and EtOH), leaves (MeOH, EtOH, EtOAc and CHCl3)], M. catarrhalis [leaves (EtOAc and CHCl3)], K. pneumoniae [stem (CHCl3), leaves (CHCl3)] and S. aureus [leaves (CHCl3)]. Seven constituents [stigmasterol (1), stigmasta-4,22-dien-3-one (2), friedelin (3), friedelane-3-one-28-al (4), 3-O-acetyl-aleuritolic acid (5), 3-O-acetyl-erythrodiol (6) and methyl-3,4,5-trihydroxybenzoate (methyl gallate) (7)] were isolated from the stem MeOH extract. All these compounds displayed some antibacterial activity against the eight pathogens with highest activity against S. saprophyticus (2µg/ml). Furthermore, this is the first report of compounds 1, 2, 3, 4, 6 and 7 isolated from A. cordifolia and where a complete set of 2D-NMR data for fridelane-3-one-28-al (4) is presented. CONCLUSION: The study demonstrated that the antibacterial activities of A. cordifolia extracts may be due to the presence of the seven isolated compounds, where compounds 3-6 showed the best activity. The observed activity against gastrointestinal, skin, respiratory and urinary tract pathogens supports the traditional use for the treatment of such ailments.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Euphorbiaceae/química , Infecciones/microbiología , Extractos Vegetales/farmacología , Enfermedades Gastrointestinales/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones del Sistema Respiratorio/microbiología , Enfermedades Cutáneas Infecciosas/microbiología , Infecciones Urinarias/microbiología
3.
Z Gastroenterol ; 52(12): 1485-92, 2014 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-25474284

RESUMEN

The intestinal microbiota has a pivotal role in the maintenance of health of the human organism, especially in the defense against pathogenic microorganisms. Alterations in the microbiota, also termed dysbiosis, seem to be involved in the pathogenesis of a variety of intestinal and extraintestinal diseases. Fecal microbiota transplantation (FMT), also known as stool transplantation, is a therapeutic procedure aiming at restoring an altered intestinal microbiota by administration of stool microorganisms from a healthy donor into the intestinal tract of a patient. FMT is most commonly used for recurrent forms of Clostridium difficile infections (CDI). There are currently many cohort studies in a large number of patients and a randomized controlled trial showing a dramatic effect of FMT for this indication. Therefore FMT is recommended by international medical societies for the treatment of recurrent CDI with high scientific evidence. Other potential indications are the treatment of fulminant CDI or the treatment of inflammatory bowel diseases. In the practical utilization of FMT there are currently several open questions regarding the screening of stool donors, the processing of stool and the mode of FMT application. Different modes of FMT application have been described, the application into the colon has to be preferred due to less reported side effects than the application into the upper gastrointestinal tract. So far only very few side effects due to FMT have been reported, nevertheless the use and risks of FMT are currently intensely debated in the medical community. This consensus report of the Austrian society of gastroenterology and hepatology (ÖGGH) in cooperation with the Austrian society of infectious diseases and tropical medicine provides instructions for physicians who want to use FMT which are based on the current medical literature.


Asunto(s)
Heces/microbiología , Gastroenterología/normas , Enfermedades Inflamatorias del Intestino/microbiología , Enfermedades Inflamatorias del Intestino/terapia , Microbiota , Guías de Práctica Clínica como Asunto , Austria , Terapia Biológica/métodos , Humanos , Trasplante Homólogo/métodos
4.
Clin Microbiol Infect ; 20(11): 1106-11, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25274251

RESUMEN

The intestinal microbiome is essential for maintaining human health and defending against intestinal pathogens. Alterations of the intestinal microbiota, also termed dysbiosis, play a pivotal role in the pathogenesis of various human diseases. Faecal microbiota transplantation (FMT) is aimed at correcting these alterations by delivering faecal microorganisms from a healthy person to the intestines of a patient. At present, recurrent Clostridium difficile infection is the only indication supported by solid scientific evidence, but many ongoing studies are investigating FMT in other dysbiosis-related diseases, such as inflammatory bowel disease. As there are no systematic methodological investigations, several questions about techniques, donor screening and safety issues remain. This shortage of evidence, especially on long-term safety concerns, is leading to worldwide controversy regarding the use of FMT. Regulations by healthcare authorities vary among different countries. This review reflects the Austrian situation and its FMT guidelines concerning indications, techniques and donor screening, recently developed by local scientific societies.


Asunto(s)
Terapia Biológica/métodos , Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/terapia , Infección Hospitalaria/terapia , Diarrea/terapia , Heces , Austria , Infecciones por Clostridium/microbiología , Infección Hospitalaria/microbiología , Diarrea/microbiología , Guías como Asunto , Política de Salud , Humanos
5.
J Ethnopharmacol ; 155(1): 123-31, 2014 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-24786571

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The antibacterial activities of 18 plants from 10 different families were investigated for their antimicrobial efficacy, based on the traditional uses of these species by Bakola pygmies living in Central Africa, especially along the Ngoyang area in Cameroon for the treatment of respiratory and tuberculosis-related symptoms. The aim of the study is to test the antimicrobial efficacy of these plants against some pathogens associated with respiratory disease and to determine if there is any validation for the traditional use against Mycobacterium species. MATERIALS AND METHODS: Medium polar extracts were prepared in MeOH/DCM (1:1, v/v) from the plant parts of each species used traditionally and were assayed against pathogens associated with respiratory tract ailments [Staphylococcus aureus (ATCC 25923), Klebsiella pneumoniae (ATCC 13883) and Morexella cattarhalis (ATCC 14468)] using the minimum inhibitory concentration (MIC) method. Two additional faster growing Mycobacterium strains [Mycobacterium smegmatis (ATCC 23246) and Mycobacterium aurum (NCTC 10437)] were included in the assay as predictive test organisms for the more pathogenic strain Mycobacterium tuberculosis. RESULTS: Some plant species, such as Alchornea floribunda, Musanga cecropioides (both leaves and stem bark), Tetracera potatoria and Xylopia aethiopica (stem bark), were effective in inhibiting Morexella cattarhalis, having MIC values between 65 and 250 µg/mL. Some noteworthy antimycobacterial inhibition (MIC≤200 µg/mL and as low as MIC 6.5 µg/mL) for 54% of the extracts were observed. CONCLUSION: While moderate activity was shown for pathogens causing respiratory tract infections, these plant species seems to be selectively targeting Mycobacteria spp. suggesting that the traditional use for treating tuberculosis related symptoms may be indeed be accurate.


Asunto(s)
Antibacterianos/farmacología , Mycobacterium/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales/química , África Central , Antibacterianos/aislamiento & purificación , Bacterias/efectos de los fármacos , Camerún , Etnofarmacología , Medicinas Tradicionales Africanas/métodos , Pruebas de Sensibilidad Microbiana , Fitoterapia/métodos , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/microbiología
6.
J Ethnopharmacol ; 151(2): 1023-7, 2014 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-24333961

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Alchornea floribunda Müll. Arg. is used in traditional medicine across Africa for the treatment of bacterial, fungal, parasitic and inflammatory disorders. AIM OF THE STUDY: To evaluate the antibacterial activity of the crude extracts of different plant parts in order to provide a scientific rationale for the proposed broad efficacy of Alchornea floribunda in the treatment of bacterial infections. MATERIALS AND METHODS: Extracts of roots, stems and leaves were prepared using solvents of various polarities in order to extract a wide range of phytochemicals. The antibacterial activity of these crude extracts was evaluated by micro-dilution assay, against Gram-positive (i.e. Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus and Staphylococcus saprophyticus) as well as Gram-negative (i.e. Escherichia coli, Klebsiella pneumoniae, Moraxella catarrhalis and Proteus mirabilis) bacteria. RESULTS: Generally, the ethanol (EtOH), methanol (MeOH), ethyl acetate (EtOAc) and chloroform (CHCl3) extracts demonstrated the best activities, with the leaves exhibiting the highest average activity for six of the eight pathogens. Of these, the ethanolic leaf extract was the most active against Staphylococcus aureus with an MIC value of 50µg/mL. Some other notable activity was observed for the ethyl acetate and chloroform root extracts against Staphylococcus aureus (50µg/mL), and for selected stem extracts against Staphylococcus aureus (50µg/mL), Klebsiella pneumoniae (63µg/mL) and Staphylococcus saprophyticus (63µg/mL). CONCLUSION: This study demonstrates the promising antibacterial activity of Alchornea floribunda against both Gram-positive and Gram-negative bacteria responsible for gastrointestinal, skin, respiratory and urinary ailments, and validates its use in the ethnopharmacology of the region.


Asunto(s)
Antibacterianos/farmacología , Euphorbiaceae , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Extractos Vegetales/farmacología , Medicinas Tradicionales Africanas , Pruebas de Sensibilidad Microbiana , Hojas de la Planta , Raíces de Plantas , Tallos de la Planta
7.
Clin Nephrol ; 72(4): 252-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19825330

RESUMEN

AIMS: The aim of this crossover study was to compare the reduction of serum phosphorus (SP) with fixed doses of the non-calcium-containing phosphate binders lanthanum carbonate (LC) and sevelamer hydrochloride (SH) in hemodialysis patients. METHODS: Following washout (2 - 3 weeks), 182 patients with SP >or= 6.0 mg/dl and calcium >or= 8.4 mg/dl were randomized (1:1) to receive LC (2,250 to 3,000 mg/day) or SH (4,800 to 6,400 mg/day) for 4 weeks. Patients underwent a second washout (2 weeks) and switched to the alternative binder for 4 weeks. RESULTS: At the end of treatment, LC had reduced SP by 1.7 +/- 0.1 mg/dl, compared with 1.4 +/- 0.1 mg/dl for SH; the difference was not statistically significant in the primary analysis (LOCF, p = 0.133). However, the reduction with LC was significantly greater than with SH in a prespecified key secondary analysis of patients who completed 4 weeks of treatment with each binder (0.5 mg/dl difference, p = 0.007). The reduction of SP was also greater with LC than SH after 1 week of treatment (p = 0.024). CONCLUSIONS: Although the primary analysis found no difference between LC and SH in the reduction of SP, a significant difference in favor of LC was observed in patients who completed treatment. The results of this study show interesting trends with respect to onset and duration of action that warrant further investigation in longer-term studies.


Asunto(s)
Quelantes/uso terapéutico , Fallo Renal Crónico/sangre , Fallo Renal Crónico/terapia , Lantano/uso terapéutico , Fósforo/sangre , Poliaminas/uso terapéutico , Diálisis Renal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Calcio/sangre , Quelantes/administración & dosificación , Estudios Cruzados , Femenino , Humanos , Lantano/administración & dosificación , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Poliaminas/administración & dosificación , Sevelamer , Resultado del Tratamiento
8.
Infection ; 34(4): 190-5, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16896576

RESUMEN

The failure rate of primary empirical anti-infective treatment of community-acquired pneumonia is reported to range between 2 and 7%. These patients are subject to a greater risk of intensive medical treatment and a higher mortality rate than patients who respond to primary treatment. We investigated 63 patients in a "real life scenario" who were admitted to the hospital after failure of primary outpatient therapy for community-acquired pneumonia. Thirty-three patients received intravenous standard therapy (betalactam 14, macrolide 3, levofloxacin 6, doxycycline 1, combinations 9 patients) while 30 patients were treated with intravenous moxifloxacin. The oral antibiotic pretreatment that failed most frequently was clarithromycin (n = 25), followed by amoxicillin/clavulanic acid (n = 16), cefixime (n = 10), cefuroxime/axetil (n = 5), doxycycline (3), cefpodoxime, and ciprofloxacin (2 each). There were no differences between the two groups in respect of age, gender, numbers of patients in nursing homes, numbers of patients with different underlying diseases (chronic bronchitis, coronary heart disease, diabetes mellitus, smoking, etc.), severity of pneumonia at the time of admission, numbers of patients requiring intensive care, and lethality. The group that underwent standard therapy experienced failure of the empirical intra-hospital antibiotic therapy more often during therapy [10 (30%) patients vs 2 (6%) in the moxifloxacin group, p = 0.009] and clinical failure of treatment on day 28 after initiation of therapy [7 (21%) patients vs 2 (6%) in the moxifloxacin group, p = 0.003]. In cases of failure of empirical preclinical antibiotic treatment for community-acquired pneumonia, subsequent intrahospital treatment with moxifloxacin is more successful than standard therapy in our study reflecting a "real life scenario".


Asunto(s)
Antibacterianos/uso terapéutico , Compuestos Aza/uso terapéutico , Neumonía Bacteriana/tratamiento farmacológico , Quinolinas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Doxiciclina/uso terapéutico , Quimioterapia Combinada , Femenino , Fluoroquinolonas , Hospitalización , Humanos , Levofloxacino , Macrólidos/uso terapéutico , Masculino , Persona de Mediana Edad , Moxifloxacino , Ofloxacino/uso terapéutico , Insuficiencia del Tratamiento , beta-Lactamas/uso terapéutico
9.
Infection ; 34(3): 148-54, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16804658

RESUMEN

BACKGROUND: The number of Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia cases is increasing in many European countries. In this observational study in one medical and three surgical ICUs multiple interventions for the treatment and eradication of nosocomial MRSA-pneumonia were used. PATIENTS AND METHODS: Twenty-one critically ill patients (age: 59 +/- 14 years, 15 males/6 females, 18 ventilator-associated, 3 nosocomial, clinical pulmonary infection score > 6 in all patients, APACHE II 18 +/- 5) were enrolled. The patients were treated with a 7-day course of iv linezolid (600 mg bid) plus rifampicin (600 mg bid), endotracheal vancomycin 100 mg qid, thrice daily mouth and throat washing with chlorhexidine 1% fluid and nasal mupirocin ointment, twice daily skin and hair washings with chlorhexidine gluconate 4% and tracheostomy (n = 8) wound care with povidone-iodine spray. Control samples (endotracheal secretions, nose, wound, and pharyngeal swabs) were taken 2, 3, 4, 7 days and 2 months thereafter. Multilobular pneumonia was seen in 16, pleural effusion in 12, and MRSA bacteremia in 4 patients. RESULTS: One patient died during the follow-up period due to cerebral bleeding. In the remaining 20 patients, pneumonia was clinically cured in all patients and all patients were free of MRSA after eradication. Six patients died due to myocardial infarction (n = 3), gram-negative septic shock (n = 2), herpes encephalitis (n = 1) > 7 days after eradication. No MRSA reinfection occurred during the control period. CONCLUSION: We conclude that in patients with MRSA pneumonia an approach using a 7-day course of intravenous linezolid plus rifampicin, intratracheal vancomycin, nasal mupirocin, cutaneous and oropharyngeal chlorhexidin plus povidone-iodine cures pneumonia and is effective for MRSA eradication.


Asunto(s)
Antibacterianos/uso terapéutico , Enfermedad Crítica , Infección Hospitalaria/tratamiento farmacológico , Resistencia a la Meticilina , Neumonía Estafilocócica/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Acetamidas , Anciano , Antibacterianos/farmacología , Infección Hospitalaria/epidemiología , Utilización de Medicamentos/estadística & datos numéricos , Femenino , Humanos , Control de Infecciones/métodos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Linezolid , Masculino , Persona de Mediana Edad , Oxazolidinonas , Rifampin , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Resultado del Tratamiento , Vancomicina/administración & dosificación
10.
Clin Nephrol ; 62(2): 104-15, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15356967

RESUMEN

BACKGROUND: Calcium carbonate used as a phosphate binder may contribute to cardiovascular calcification. Long-term comparisons of sevelamer, a non-calcium polymeric phosphate binder, and calcium carbonate (CC) are lacking. METHODS: 114 adult hemodialysis patients were randomly assigned to open label sevelamer or CC for 52 weeks. Study efficacy endpoints included changes in serum phosphorus, calcium, calcium-phosphorus product, and lipids. In addition, initial and sequential electron beam computerized tomography scans were performed to assess cardiovascular calcification status and change during follow-up. Safety endpoints were serum biochemistry, blood cell counts and adverse events. RESULTS: Patients receiving sevelamer had a similar reduction in serum phosphorus as patients receiving CC (sevelamer -0.58 +/- 0.68 mmol/l, CC -0.52 +/- 0.50 mmol/l; p = 0.62). Reductions in calcium-phosphorus product were not significantly different (sevelamer -1.4 +/- 1.7 mmol2/l2, CC -0.9 +/- 1.2 mmol2/l2; p = 0.12). CC produced significantly more hypercalcemia (> 2.8 mmol/l in 0% sevelamer and 19% CC patients, p < 0.01) and suppressed intact parathyroid hormone below 150 pg/ml in the majority of patients. Sevelamer patients experienced significant (p < 0.01) reductions in total (-1.2 +/- 0.9 mmol/l, -24%) and LDL cholesterol (-1.2 +/- 0.9 mmol/l, -30%). CC patients had significant increases in coronary artery (median +34%, p < 0.01) and aortic calcification (median +32%, p < 0.01) that were not observed in sevelamer-treated patients. Patients on sevelamer required more grams of binder (sevelamer 5.9 g vs. CC 3.9 g) and experienced more dyspepsia than patients on calcium carbonate. CONCLUSIONS: Sevelamer is an effective phosphate binder that unlike calcium carbonate is not associated with progressive cardiovascular calcification in hemodialysis patients.


Asunto(s)
Calcinosis/prevención & control , Carbonato de Calcio/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Compuestos Epoxi/uso terapéutico , Fallo Renal Crónico/complicaciones , Fósforo/metabolismo , Polietilenos/uso terapéutico , Diálisis Renal , Adulto , Calcinosis/etiología , Enfermedades Cardiovasculares/etiología , Femenino , Humanos , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Poliaminas , Sevelamer , Factores de Tiempo
11.
Eur J Clin Invest ; 31(3): 258-63, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11264655

RESUMEN

High-intensity exercise leads to an increased risk of upper respiratory tract infections in athletes, which had been related to an exercise-induced impairment of neutrophil function. In this study, several indices of neutrophil function were analysed before and after a biathlon and the effect of oral vitamin C on neutrophil function was determined. Six athletes took 2 g vitamin C daily for 1 week prior to a biathlon and four athletes did not take any supplementation. Neutrophil phagocytosis was analysed by fluorescence microscopy and flow cytometry. Cytosolic calcium kinetics were assessed fluorometrically and neutrophil bactericidal ability was assessed by fluorescence microscopy. Reactive oxygen production was analysed by flow cytometry. Catecholamines were analysed by high-performance liquid chromatography. After high-intensity exercise there were significant reductions in the number of phagocytosed Escherichia coli per neutrophil and in neutrophil bactericidal ability. There was a significant exercise-dependent increase of catecholamines. There was no difference between the two groups of athletes. These results do not support the concept that vitamin C supplementation corrects neutrophil dysfunction after strenuous exercise.


Asunto(s)
Ácido Ascórbico/farmacología , Ejercicio Físico/fisiología , Neutrófilos/efectos de los fármacos , Adulto , Ciclismo/fisiología , Actividad Bactericida de la Sangre/efectos de los fármacos , Calcio/metabolismo , Catecolaminas/sangre , Humanos , Líquido Intracelular/metabolismo , Masculino , Neutrófilos/química , Neutrófilos/fisiología , Fagocitosis/efectos de los fármacos , Fagocitosis/fisiología , Especies Reactivas de Oxígeno/metabolismo
12.
J Neurol Neurosurg Psychiatry ; 67(4): 445-50, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10486389

RESUMEN

OBJECTIVES: Catatonia is a psychomotor syndrome with concomittant akinesia and anxiety which both respond almost immediately to benzodiazepines such as lorazepam. The benzodiazepine receptor distribution was therefore investigated in akinetic catatonia with single photon emission tomography (SPECT) using iodine-123-iomazenil ((123) I Iomazenil). METHODS: Ten akinetic catatonic patients, 10 psychiatric controls (similar age, sex, medication, and underlying psychiatric diagnosis but without catatonic syndrome), and 20 healthy controls were investigated with SPECT 2 hours after injection of (123) I Iomazenil. To exclude potential effects of cerebral perfusion (r-CBF) r-CBF was additionally investigated with Tc-99mECD SPECT. RESULTS: Catatonic patients showed significantly lower iomazenil binding and altered right-left relations in the left sensorimotor cortex compared with psychiatric (p<0.001) and healthy (p<0.001) controls. In addition, there was significantly lower r-CBF in the right lower prefrontal and parietal cortex in catatonia whereas in the left sensorimotor cortex no differences in r-CBF between groups were found. Catatonic motor and affective symptoms showed significant correlations (p<0.05) with benzodiazepine binding in the left sensorimotor cortex as well as with right parietal r-CBF. CONCLUSIONS: Reduced iomazenil binding suggests decreased density of GABA-A receptors in the left sensorimotor cortex in akinetic catatonia. In addition to reduced GABA-A receptor density in the left sensorimotor cortex the parietal cortex seems to be involved in pathophysiology of catatonic symptoms. It is concluded that, considering results from correlation analyses, both emotional and motor symptoms in catatonia seem to be closely related to left sensorimotor and right parietal alterations.


Asunto(s)
Catatonia/diagnóstico por imagen , Corteza Motora/diagnóstico por imagen , Receptores de GABA-A/metabolismo , Adulto , Análisis de Varianza , Unión Competitiva , Catatonia/metabolismo , Catatonia/psicología , Femenino , Flumazenil/análogos & derivados , Flumazenil/metabolismo , Humanos , Masculino , Corteza Motora/metabolismo , Escalas de Valoración Psiquiátrica , Tomografía Computarizada de Emisión de Fotón Único
13.
Toxicology ; 125(2-3): 169-81, 1998 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-9570331

RESUMEN

The nephrotoxic potential of ascomycin, the C21-ethyl analogue of FK506, was defined and ways explored to enhance its detection. After 14-day dosing in the Fischer-344 rat, FK506 and ascomycin reduced creatinine clearance by >50% at doses of 1 and 3 mg/kg, i.p., respectively. Ascomycin also had a 3-fold lower immunosuppressive potency in a popliteal lymph node hyperplasia assay, resulting in an equivalent therapeutic index consistent with a common mechanistic dependence on calcineurin inhibition. Renal impairment with different routes of administration was correlated with pharmacokinetics. Sensitivity of detection was not adequate with shorter dosing durations in rats with unilateral nephrectomy or in mice using a cytochrome P-450 inhibitor, SKF-525A. In 14-day studies, nephrotoxicity was not induced by continuous i.p. infusion of ascomycin at 10 mg/kg/day or daily oral administration (up to 50 mg/kg/day) in rats on a normal diet, nor by continuous i.v. infusion (up to 6 mg/kg/day) in rats on a low salt diet to enhance susceptibility. The lack of toxicity at high oral doses of FK506 or ascomycin, and the finding of non-linear oral pharmacokinetics of ascomycin show that this drug class has an oral absorption ceiling. The negative results with continuous infusion suggest that ascomycin nephrotoxicity is governed by peak drug levels. In addition to defining ways to meaningfully compare the nephrotoxic potential of FK506 derivatives, these results have implications for overall safety assessment and improved clinical use.


Asunto(s)
Inmunosupresores/toxicidad , Enfermedades Renales/inducido químicamente , Tacrolimus/análogos & derivados , Tacrolimus/toxicidad , Animales , Disponibilidad Biológica , Dieta Hiposódica , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Evaluación Preclínica de Medicamentos , Inmunosupresores/farmacocinética , Enfermedades Renales/metabolismo , Masculino , Tasa de Depuración Metabólica , Ratones , Ratones Endogámicos , Modelos Biológicos , Nefrectomía , Ratas , Ratas Endogámicas , Tacrolimus/farmacocinética
14.
J Recept Signal Transduct Res ; 17(1-3): 227-42, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9029493

RESUMEN

Ligand-gated channels (LGCs) play a fundamental role in the fast transmission of electrical activity from neuron to neuron and/or to effector cells. Studies of LGCs in isolation have become possible since the identification of genes coding for these membrane proteins together with the establishment of reconstitution techniques in host systems. Methods for electrophysiological investigations of LGCs reconstituted either in the Xenopus oocytes or stably tranfected in cell lines are discussed. Functional studies of reconstituted receptors enable fast determination of LGCs' pharmacological profiles and comparison of their physiological properties. Combination of molecular engineering with physiological measurements allows studies with unpreceeding resolution and it is now possible to examine at the amino-acid level the contribution of some residues in the formation of the ligand-binding site or the ionic channel domains.


Asunto(s)
Activación del Canal Iónico/fisiología , Canales Iónicos/fisiología , Acetilcolina/metabolismo , Alcaloides/metabolismo , Animales , Azocinas , Unión Competitiva , Curare/metabolismo , Dihidro-beta-Eritroidina/metabolismo , Electrofisiología , Femenino , Humanos , Activación del Canal Iónico/genética , Canales Iónicos/genética , Oocitos/metabolismo , Quinolizinas , Receptores Colinérgicos/genética , Receptores Colinérgicos/fisiología , Receptores de GABA-A/genética , Receptores de GABA-A/fisiología , Receptores de Glutamato/genética , Receptores de Glutamato/fisiología , Receptores de Serotonina/genética , Receptores de Serotonina/fisiología , Receptores de Serotonina 5-HT3 , Xenopus laevis
15.
J Antibiot (Tokyo) ; 44(12): 1331-41, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1723403

RESUMEN

The immunosuppressive effects of the dunaimycins, a new complex of spiroketal 24-membered macrolides, were compared to cyclosporin A, ascomycin, and rapamycin. Each dunaimycin was a potent inhibitor of the mitogenic response observed in mixed murine splenocyte or human leukocyte cultures, and like immunosuppressive drugs these compounds were relatively less potent inhibitors of the constitutive proliferation of murine EL4 thymoma cells. Dunaimycin D4S showed no selectivity in inhibiting the mitogenic response of spleen cells to concanavalin A, pokeweed mitogen, lipopolysaccharide, or phytohemagglutinin. Cyclosporin A and ascomycin did not inhibit interleukin 2 dependent proliferation, whereas the dunaimycins and rapamycin blocked the uptake of [3H]thymidine in mixed cultures supplemented with exogenous interleukin 2. In addition, dunaimycin D4S had no apparent affinity for cyclosporin A or FK-506 immunophilins. Although the dunaimycins inhibited the activity of Na+, K(+)-ATPase, inhibition of this enzyme appeared insufficient to explain the biological activity of these new macrolides. Over a narrow concentration range, dunaimycin D4S showed in vivo immunosuppressive activity in the murine popliteal lymph node hyperplasia model.


Asunto(s)
Antibacterianos/farmacología , Inmunosupresores/farmacología , Animales , Ciclosporina/farmacocinética , Ciclosporina/farmacología , Humanos , Prueba de Cultivo Mixto de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Oligomicinas/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Tacrolimus/farmacología
16.
Cancer ; 54(12): 2850-3, 1984 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-6498763

RESUMEN

Twenty-one patients with adenocarcinoma of the cecum were treated in a pilot study between October, 1972 and June, 1982 by right hemicolectomy and received adjuvant postoperative irradiation (40-45 Gy/4-5 weeks) and 5-Fluorouracil (5-FU). There were 15, 4, and 2 patients with Stages (Astler-Coller) B2, C2, and D, respectively. There was no major morbidity nor mortality attributable to the adjuvant therapy. Patients were followed for a minimum of 15 months. Fifteen patients are alive and disease-free, with a median survival of 34 months (range, 17-79). There were no significant differences in the median survival or incidence of distant metastases when the adjuvant therapy group was matched by sex, age, and stage of disease with a group of patients treated by right hemicolectomy alone. There was a lower local failure rate in the adjuvant group compared with the surgery-alone group (5% versus 19%) (P less than 0.2). These data suggest that adjuvant therapy for cecal carcinoma is feasible, safe, and may reduce local failures and possibly improve survival in high-risk patients. It deserves further investigation so that a definite conclusion may be drawn.


Asunto(s)
Adenocarcinoma/terapia , Neoplasias del Ciego/terapia , Fluorouracilo/uso terapéutico , Adenocarcinoma/radioterapia , Adenocarcinoma/cirugía , Adulto , Anciano , Neoplasias del Ciego/radioterapia , Neoplasias del Ciego/cirugía , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto
17.
Neurosci Lett ; 11(2): 177-80, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-379710

RESUMEN

Adjacent serial sections of the organum vasculosum laminal terminalis (OVLT) of the rat were incubated with antisera of luteinizing-hormone--releasing-hormone (LH-RH) and somatostatin and stained by the peroxidase-antiperoxidase technique. The distribution patterns of the two oligopeptides show distinct differences, as already found in the median eminence. A denser, more centrally placed somatostatin deposit is surrounded by a more extensive, looser, more peripheral one of LH0RH. These differences in distribution may reflect an anatomical basis for the differing effects of various manipulations on the OVLT and median eminence stores.


Asunto(s)
Hormona Liberadora de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Somatostatina/metabolismo , Animales , Femenino , Técnicas para Inmunoenzimas , Masculino , Ratas
19.
Br J Nutr ; 33(1): 73-85, 1975 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1115753

RESUMEN

1. The effects of retinol and retinoic acid supplementation of retinol-deficient rats were studied for a variety of metabolic processes shown to be affected by retinol-deficiency. 2. Retinol-deficient rats were found to have decreased body-weight, liver and testes weights, a degeneration of testicular germinal cells, an increased incorporation of labelled choline into liver and testes phospholipids, an increased protein synthetic activity (in vitro) of liver ribosomes, an increased transfer-RNA methyltransferase activity in liver and a decreased activity in testes, an increased DNA content of testicular nuclei, and a decreased uptake of [3-H]thymidine by testicular nuclear DNA. 3. In retinol-deficient rats supplemented for 8 weeks with retinol these changes were reversed, measurements returning to control levels. 4. In retinol-deficient rats supplemented for 8 weeks with retinoic acid all changes were reversed except those in the testes. 5. Testicular signs of retinol deficiency appeared to be delayed when retinoic acid was added to the retinol-deficient diet of weanling rats. This suggests a sparing action of retinoic acid on the rat's utilization of retinol. 6. Suggestions are offered as to why retinoic acid will support growth and development but not spermatogenesis in the rat.


Asunto(s)
Deficiencia de Vitamina A/metabolismo , Vitamina A/análogos & derivados , Animales , Animales Recién Nacidos , Peso Corporal , Colina/metabolismo , ADN/metabolismo , Ácidos Grasos Insaturados/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Tamaño de los Órganos , Fosfolípidos/metabolismo , Biosíntesis de Proteínas , Ratas , Espermatogénesis , Testículo/efectos de los fármacos , Testículo/metabolismo , Timidina/metabolismo , Tritio , Vitamina A/farmacología , ARNt Metiltransferasas/análisis
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