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1.
Metabolomics ; 15(5): 72, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-31049735

RESUMEN

INTRODUCTION: Dietary exposure monitoring within populations is reliant on self-reported measures such as Food Frequency Questionnaires and diet diaries. These methods often contain inaccurate information due to participant misreporting, non-compliance and bias. Urinary metabolites derived from individual foods could provide additional objective indicators of dietary exposure. For biomarker approaches to have utility it is essential that they cover a wide-range of commonly consumed foods and the methodology works in a real-world environment. OBJECTIVES: To test that the methodology works in a real-world environment and to consider the impact of the major sources of likely variance; particularly complex meals, different food formulations, processing and cooking methods, as well as the dynamics of biomarker duration in the body. METHODS: We designed and tested a dietary exposure biomarker discovery and validation strategy based on a food intervention study involving free-living individuals preparing meals and collecting urine samples at home. Two experimental periods were built around three consecutive day menu plans where all foods and drinks were provided (n = 15 and n = 36). RESULTS: The experimental design was validated by confirming known consumption biomarkers in urinary samples after the first menu plan. We tested biomarker performance with different food formulations and processing methods involving meat, wholegrain, fruits and vegetables. CONCLUSION: It was demonstrated that spot urine samples, together with robust dietary biomarkers, despite major sources of variance, could be used successfully for dietary exposure monitoring in large epidemiological studies.


Asunto(s)
Biomarcadores/orina , Dieta , Ingestión de Alimentos , Metabolómica , Bebidas , Estudios Cruzados , Dieta Saludable/normas , Alimentos , Humanos , Metaboloma , Reino Unido
2.
MethodsX ; 11: 102298, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37601288

RESUMEN

Heavy metal pollution in surface waters has become a major worldwide issue as people tend to settle where there is readily available source of water like a river. This research evaluates the causes, concentration and associated health risks of heavy metals in River Sosiani as it passes through the town of Eldoret. Seven water samples were collected and analysed for zinc (Zn), copper (Cu) and lead (Pb. The results disclosed that Pb concentrations were estimated to be in the range of 0.06 mg/l to 0.23 mg/l, higher than the permitted limit by WHO of 0.01 mg/l. Cu and Zn concentration levels were below the permissible limits. The chronic daily intake (CDI) indicated that total hazard quotient of non-cancer risk of Pb was above one and the total HI values for children were greatly elevated compared to those of adults in the studied area. This showed a high risk in exposure to Pb. Health human risk was assessed and the incremental life cancer risk (ILCR) values of Pb for children and adults in all sites were found to be negligible with values below 10-6. However, there is higher cancer and non-cancer risk for children than adults as far as lead metal is concerned. Therefore, measures should be taken in accordance with the standards to prevent potential risk of the river pollution.•Human activities make a significant contribution to heavy metal pollution to surface waters which is a threat to humans.•Water from Sosiani River is not safe for use domestically as far as lead metal levels are concerned.•The results of this study can be used by decision makers to develop measures which can improve the quality of water in the river catchment.

3.
Clin Oncol (R Coll Radiol) ; 35(9): e498-e505, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37433701

RESUMEN

AIMS: Osteoradionecrosis (ORN) is a serious toxicity of head and neck radiotherapy. It predominantly affects the mandible. Extra-mandibular ORN is rare. The aim of this study was to report the incidence and outcomes of extra-mandibular ORNs from a large institutional database. MATERIALS AND METHODS: In total, 2303 head and neck cancer patients were treated with radical or adjuvant radiotherapy. Of these, extra-mandibular ORN developed in 13 patients (0.5%). RESULTS: Maxillary ORNs (n = 8) were a consequence of the treatment of various primaries (oropharynx = 3, sinonasal = 2, maxilla = 2, parotid = 1). The median interval from the end of radiotherapy to the development of ORN was 7.5 months (range 3-42 months). The median radiotherapy dose in the centre of the ORN was 48.5 Gy (range 22-66.5 Gy). Four patients (50%) healed in 7, 14, 20 and 41 months. All temporal bone ORNs (n = 5) developed after treatment to the parotid gland (of a total of 115 patients who received radiotherapy for parotid gland malignancy). The median interval from the end of radiotherapy to the development of ORN was 41 months (range 20-68 months). The median total dose in the centre of the ORN was 63.5 Gy (range 60.2-65.3 Gy). ORN healed in only one patient after 32 months of treatment with repeated debridement and topical betamethasone cream. CONCLUSION: Extra-mandibular ORN is a rare late toxicity and this current study provides useful information on its incidence and outcome. The risk of temporal bone ORN should be considered in the treatment of parotid malignancies and patients should be counselled. More research is required to determine the optimal management of extra-mandibular ORN, particularly on the role of the PENTOCLO regimen.


Asunto(s)
Neoplasias de Cabeza y Cuello , Enfermedades Mandibulares , Osteorradionecrosis , Humanos , Estudios Retrospectivos , Osteorradionecrosis/epidemiología , Osteorradionecrosis/etiología , Dosificación Radioterapéutica , Enfermedades Mandibulares/complicaciones , Enfermedades Mandibulares/epidemiología , Neoplasias de Cabeza y Cuello/radioterapia , Mandíbula
4.
Br J Oral Maxillofac Surg ; 60(2): 168-173, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34857411

RESUMEN

In head and neck cancer (HNC), osteoradionecrosis (ORN) is one of the most significant complications of radiotherapy (RT). With an absence of effective non-surgical treatment, prevention of the development of ORN is the best approach. The purpose of this study was to identify the risk factors for the development of ORN in HNC. Records of 1,118 patients with HNC treated with radical RT (≥55Gy) from January 2010 to December 2019 were reviewed. After applying the exclusion criteria, 935 patients were included in the final analysis. In patients with confirmed ORN, exact RT doses were mapped. In total, 91 patients were found (9.7%) with a median (range) time of eight (3-89) months to the development of ORN. Smoking, having a primary site in the oropharynx, bone surgery before adjuvant RT, the addition of concurrent chemotherapy, the presence of xerostomia, dental extraction pre-RT, the time ≤20 days between dental extraction and start of RT, and receiving >55Gy RT dose were significant factors for its development. This comprehensive analysis including the precise RT dose mapping has shown the risk factors for the development of ORN. In practice, every effort should be made to avoid these risk factors without compromising the oncology treatment. The findings of this analysis may provide a basis for future prospective research on this topic.


Asunto(s)
Neoplasias de Cabeza y Cuello , Osteorradionecrosis , Neoplasias de Cabeza y Cuello/complicaciones , Humanos , Osteorradionecrosis/etiología , Estudios Retrospectivos , Factores de Riesgo , Extracción Dental/efectos adversos , Resultado del Tratamiento
5.
Cochrane Database Syst Rev ; (1): CD002290, 2008 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-18254005

RESUMEN

BACKGROUND: Eighty to 90% of children with steroid-sensitive nephrotic syndrome (SSNS) have relapses. About half relapse frequently and are at risk of the adverse effects of corticosteroids. Non-corticosteroid immunosuppressive agents are used to prolong periods of remission in these children, however these agents have significant potential adverse effects. Currently there is no consensus as to the most appropriate second line agent in children who are steroid sensitive, but who continue to relapse. OBJECTIVES: To evaluate the benefits and harms of non-corticosteroid immunosuppressive agents in relapsing SSNS in children. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, reference lists, conference abstracts and contact with known investigators. Search date: September 2007 SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-RCTs were included if they compared non-corticosteroid agents with placebo, prednisone or no treatment, different doses and/or durations of the same non-corticosteroid agent, different non-corticosteroid agents. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as relative risk (RR) with 95% confidence intervals (CI). MAIN RESULTS: We identified 26 studies (1173 children). Cyclophosphamide (RR 0.44, 95% CI 0.26 to 0.73) and chlorambucil (RR 0.15, 95% CI 0.02 to 0.95) significantly reduced the relapse risk at six to twelve months compared with prednisone alone. There was no difference in relapse risk at two years between chlorambucil and cyclophosphamide (RR 1.31, 95% CI 0.80 to 2.13). There was no difference at one year between intravenous and oral cyclophosphamide (RR 0.99, 95% CI 0.76 to 1.29). Cyclosporin was as effective as cyclophosphamide (RR 1.07, 95% CI 0.48 to 2.35) and chlorambucil (RR 0.82, 95% CI 0.44 to 1.53) and levamisole (RR 0.43, 95% CI 0.27 to 0.68) was more effective than steroids alone but the effects were not sustained once treatment was stopped. There was no difference in the risk for relapse between mycophenolate mofetil and cyclosporin (RR 5.00, 95% CI 0.68 to 36.66) but CI were large. Mizoribine and azathioprine were no more effective than placebo or prednisone alone in maintaining remission. AUTHORS' CONCLUSIONS: Eight week courses of cyclophosphamide or chlorambucil and prolonged courses of cyclosporin and levamisole reduce the risk of relapse in children with relapsing SSNS compared with corticosteroids alone. Clinically important differences in efficacy are possible and further comparative studies are still needed.


Asunto(s)
Inmunosupresores/uso terapéutico , Síndrome Nefrótico/tratamiento farmacológico , Adolescente , Azatioprina/uso terapéutico , Niño , Preescolar , Clorambucilo/uso terapéutico , Ciclofosfamida/uso terapéutico , Ciclosporina/uso terapéutico , Humanos , Lactante , Levamisol/uso terapéutico , Síndrome Nefrótico/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Ribonucleósidos/uso terapéutico , Prevención Secundaria
6.
Cochrane Database Syst Rev ; (4): CD001533, 2007 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-17943754

RESUMEN

BACKGROUND: In nephrotic syndrome (NS) protein leaks from the blood to the urine through the glomeruli resulting in hypoproteinaemia and generalised oedema. While the majority of children with NS respond to corticosteroids, 70% experience a relapsing course. Corticosteroids have reduced the mortality rate to around 3%. However corticosteroids have well recognised potentially serious adverse effects such as obesity, poor growth, hypertension, diabetes mellitus and osteoporosis. OBJECTIVES: To determine the benefits and harms of corticosteroid regimens in preventing relapse in children with steroid sensitive NS (SSNS). SEARCH STRATEGY: We searched CENTRAL, Cochrane Renal Group Specialised Register, MEDLINE and EMBASE without language restriction, reference lists of articles and contact with known investigators. Date of last search: December 2006 SELECTION CRITERIA: Randomised controlled trials performed in children (three months to 18 years) in their initial or subsequent episode of SSNS, comparing different durations, total doses or other dose strategies using any corticosteroid agent, with outcome data at six months or more. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. Results were expressed as relative risk (RR) with 95% confidence intervals (CI) or mean difference (WMD). Meta-regression was used to explore potential between-study differences due to baseline risk of relapse, study quality and interventions. MAIN RESULTS: Twenty four trials were identified. Six trials comparing two months of prednisone or prednisolone with three months or more in the first episode showed longer duration significantly reduced the risk of relapse at 12 to 24 months (RR 0.70, 95% CI 0.58 to 0.84). There was an inverse linear relationship between treatment duration and risk of relapse (RR = 1.26 - 0.112 duration; P = 0.03). Four trials showed that six months of prednisone was more effective than three months in reducing the risk for relapse (RR 0.57; 95% CI 0.45 to 0.71). Deflazacort was significantly more effective in maintaining remission than prednisone in children who frequently relapsed in a single study (RR 0.44, 95% CI 0.25 to 0.78). There were no increases in adverse events. AUTHORS' CONCLUSIONS: Children in their first episode of SSNS should be treated for at least three months with an increase in benefit for up to seven months of treatment. For a baseline risk for relapse following the first episode of 60% with two months of therapy, daily prednisone or prednisolone given for four weeks followed by alternate-day therapy for six months would reduce the number of children relapsing by 33%.


Asunto(s)
Antiinflamatorios/uso terapéutico , Glucocorticoides/uso terapéutico , Síndrome Nefrótico/tratamiento farmacológico , Adolescente , Niño , Preescolar , Glucocorticoides/efectos adversos , Humanos , Lactante , Prednisona/uso terapéutico , Pregnenodionas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Prevención Secundaria
7.
Cochrane Database Syst Rev ; (4): CD003772, 2007 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-17943796

RESUMEN

BACKGROUND: Urinary tract infection (UTI) is one of the most common bacterial infection in infants. The most severe form of UTI is acute pyelonephritis, which results in significant acute morbidity and may cause permanent renal damage. Published guidelines recommend treatment of acute pyelonephritis initially with intravenous (IV) therapy followed by oral therapy for seven to 14 days though there is no consensus on the duration of either IV or oral therapy. OBJECTIVES: To determine the benefits and harms of different antibiotic regimens for the treatment of acute pyelonephritis in children. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, reference lists of articles and conference proceedings without language restriction. Date of most recent search: December 2006. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing different antibiotic agents, routes, frequencies or durations of therapy in children aged 0 to 18 years with proven UTI and acute pyelonephritis were selected. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study quality and extracted data. Statistical analyses were performed using the random effects model and the results expressed as relative risk (RR) for dichotomous outcomes or mean difference (WMD) for continuous data with 95% confidence intervals (CI). MAIN RESULTS: Twenty three studies (3295 children) were eligible for inclusion. No significant differences were found in persistent renal damage at 6 months (2 studies, 424 children: RR 0.87, 95% CI 0.35 to 2.16) or in duration of fever (2 studies, 693 children: WMD 1.54, 95% CI -1.67 to 4.76) between oral antibiotic therapy (10 to 14 days) and IV therapy (3 days) followed by oral therapy (10 days). Similarly no significant differences in persistent renal damage (3 studies, 341 children: RR 1.13, 95% CI 0.86 to 1.49) were found between IV therapy (3 to 4 days) followed by oral therapy and IV therapy for 7 to 14 days. No significant differences in efficacy were found between daily and thrice daily administration of aminoglycosides (1 study, 179 children, persistent symptoms at 3 days: RR 1.98, 95% CI 0.37 to 10.53). AUTHORS' CONCLUSIONS: These results suggest that children with acute pyelonephritis can be treated effectively with oral antibiotics (cefixime, ceftibuten and amoxycillin/clavulanic acid) or with short courses (2 to 4 days) of IV therapy followed by oral therapy. If IV therapy is chosen, single daily dosing with aminoglycosides is safe and effective. Studies are required to determine the optimal total duration of therapy.


Asunto(s)
Antibacterianos/uso terapéutico , Pielonefritis/tratamiento farmacológico , Enfermedad Aguda , Administración Oral , Adolescente , Niño , Humanos , Lactante , Inyecciones Intravenosas , Ensayos Clínicos Controlados Aleatorios como Asunto
8.
Cochrane Database Syst Rev ; (1): CD001890, 2007 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-17253467

RESUMEN

BACKGROUND: Metabolic acidosis is a feature of chronic kidney disease (CKD) due to the reduced capacity of the kidney to synthesise ammonia and excrete hydrogen ions. It has adverse consequences on protein and muscle metabolism, bone turnover and the development of renal osteodystrophy. Metabolic acidosis may be corrected by oral bicarbonate supplementation or in dialysis patients by increasing the bicarbonate concentration in dialysate fluid. OBJECTIVES: To examine the benefits and harms of treating metabolic acidosis in patients with CKD, both prior to reaching end-stage renal disease (ESRD) or whilst on renal replacement therapy (RRT), with sodium bicarbonate or increasing the bicarbonate concentration of dialysate. SEARCH STRATEGY: We searched CENTRAL (The Cochrane Library, issue 4 2005), Cochrane Renal Group's specialised register (October 2005), MEDLINE (1966 - October 2005) and EMBASE (1980 - October 2005). SELECTION CRITERIA: Randomised controlled trials (RCTs), crossover RCTs and quasi-RCTs investigating the correction of chronic metabolic acidosis in adults or children with CKD. DATA COLLECTION AND ANALYSIS: Outcomes were analysed using relative risk (RR) and weighted mean difference (MD) for continuous measures. MAIN RESULTS: We identified three trials in adult dialysis patients (n = 117). There were insufficient data for most outcomes for meta-analysis. In all three trials acidosis improved in the intervention group though there was variation in achieved bicarbonate level. There was no evidence of effect on blood pressure or sodium levels. Some measures of nutritional status/protein metabolism (e.g. SGA, NP NA) were significantly improved by correction in the one trial that looked in these in detail. There was heterogeneity of the effect on serum albumin in two trials. Serum PTH fell significantly in the two trials that estimated this, there was no significant effect on calcium or phosphate though both fell after correction. Complex bone markers were assessed in one study, with some evidence for a reduction in bone turnover in those with initial high bone turnover and an increase in low turnover patients. The studies were underpowered to assess clinical outcomes, in the one study that did there was some evidence for a reduction in hospitalisation after correction. AUTHORS' CONCLUSIONS: The evidence for the benefits and risks of correcting metabolic acidosis is very limited with no RCTs in pre-ESRD patients, none in children, and only three small trials in dialysis patients. These trials suggest there may be some beneficial effects on both protein and bone metabolism but the trials were underpowered to provide robust evidence.


Asunto(s)
Acidosis/terapia , Enfermedades Renales/complicaciones , Diálisis Renal , Bicarbonato de Sodio/uso terapéutico , Enfermedad Crónica , Soluciones para Hemodiálisis/uso terapéutico , Humanos , Enfermedades Renales/metabolismo
9.
Eur J Clin Nutr ; 71(12): 1371-1380, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28294172

RESUMEN

Randomised controlled trials (RCTs) have observed contrasting results on the effects of vitamin C on circulating biomarkers of glycaemic and insulin regulation. We conducted a systematic review and meta-analysis of RCTs testing the effect of vitamin C administration on glucose, HbA1c and insulin concentrations. Four databases (PubMed, Embase, Scopus and Cochrane Library) were used to retrieve RCTs published from inception until April 2016 and testing the effects of vitamin C in adult participants. The screening of 2008 articles yielded 22 eligible studies (937 participants). Overall, vitamin C did not modify glucose, HbA1c and insulin concentrations. However, subgroup analyses showed that vitamin C significantly reduced glucose concentrations (-0.44 mmol/l, 95% CI: -0.81, -0.07, P=0.01) in patients with type 2 diabetes and in interventions with a duration greater than 30 days (-0.53%, 95% CI: -0.79, -0.10, P=0.02). Vitamin C administration had greater effects on fasting (-13.63 pmol/l, 95% CI: -22.73, -4.54, P<0.01) compared to postprandial insulin concentration. Meta-regression analyses showed that age was a modifier of the effect of vitamin C on insulin concentration. Furthermore, the effect size was associated with baseline BMI and plasma glucose levels, and with the duration of the intervention. In conclusion, greater reduction in glucose concentrations observed in patients with diabetes, older individuals and with more prolonged supplementation. Personalised interventions with vitamin C may represent a feasible future strategy to enhance benefits and efficacy of interventions. Nevertheless, results need to be interpreted cautiously due to limitations in the primary studies analysed.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/sangre , Glucemia/metabolismo , Suplementos Dietéticos , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada/metabolismo , Humanos , Insulina/sangre , Ensayos Clínicos Controlados Aleatorios como Asunto , Sensibilidad y Especificidad
10.
Cochrane Database Syst Rev ; (3): CD003264, 2006 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-16856001

RESUMEN

BACKGROUND: Chronic kidney disease (CKD) is an uncommon but important condition. Growth retardation, one of the complications of CKD, is of concern to families. Recombinant human growth hormone (rhGH) treatment has been used to help short children with CKD attain a height more in keeping with their age group. However, there are concerns that rhGH may have an adverse effect on the preservation of native kidney function, predispose to acute rejection in kidney transplant recipients, and cause benign intracranial hypertension and slipped capital femoral epiphysis. OBJECTIVES: To evaluate the benefits and harms of rhGH treatment in children with CKD. SEARCH STRATEGY: Randomised controlled trials (RCTs) were identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, article reference lists and through contact with local and international experts in the field. Date of most recent search: July 2005 SELECTION CRITERIA: RCTs were included if they were carried out in children aged 0-18 years, diagnosed with CKD, who were pre-dialysis, on dialysis or post-transplant; if they compared rhGH treatment with placebo/no treatment or two doses of rhGH treatments; and if they included height outcomes. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed studies for methodological quality and extracted data from eligible trials. Data was pooled using a random effects model with calculation of weighted mean difference (MD) for continuous outcomes and relative risk (RR) for categorical outcomes with 95% confidence intervals (CI). MAIN RESULTS: Fifteen RCTs (629 children) were identified. Treatment with rhGH (28 IU/m(2)/wk) resulted in a significant increase in height standard deviation score (SDS) at one year (MD 0.78 SDS, 95% CI 0.52 to 1.04), and a significant increase in height velocity at six months (MD 2.85 cm/6 mo, 95%CI 2.22 to 3.48) and one year (MD 3.80 cm/y, 95%CI 3.20 to 4.39). Compared to the 14 IU/m(2)/wk group, there was a 1.34 cm/y (0.55 to 2.13) increase in height velocity in the 28 IU/m(2)/wk group. The frequency of reported side effects of rhGH were similar to that of the control group. AUTHORS' CONCLUSIONS: One year of 28 IU/m(2)/wk rhGH in children with CKD resulted in a 3.80 cm/y increase in height velocity above that of untreated patients. Trials were too short to determine if continuing treatment resulted in an increase in final adult height.


Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona del Crecimiento/uso terapéutico , Fallo Renal Crónico/complicaciones , Adolescente , Niño , Preescolar , Trastornos del Crecimiento/etiología , Humanos , Lactante , Recién Nacido , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Oncogene ; 20(36): 5054-8, 2001 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-11526490

RESUMEN

Mutations in the c-KIT receptor occur somatically in many sporadic Gastrointestinal Stromal Tumors (GIST), and similar mutations have been identified at the germline level in kindreds with multiple GISTs. These mutations activate the tyrosine kinase activity of c-KIT and induce constitutive signaling. To investigate the function of activated c-KIT in GIST, we established a human GIST cell line, GIST882, which expresses an activating KIT mutation (K642E) in the first part of the cytoplasmic split tyrosine kinase domain. Notably, the K642E substitution is encoded by a homozygous exon 13 missense mutation, and, therefore, GIST882 cells do not express native KIT. GIST882 c-KIT protein is constitutively tyrosine phosphorylated, but tyrosine phosphorylation was rapidly and completely abolished after incubating the cells with the selective tyrosine kinase inhibitor STI571. Furthermore, GIST882 cells evidenced decreased proliferation and the onset of apoptotic cell death after prolonged incubation with STI571. Similar results were obtained after administering STI571 to a primary GIST cell culture that expressed a c-KIT exon 11 juxtamembrane mutation (K558NP). These cell-culture-based studies support an important role for c-KIT signaling in GIST and suggest therapeutic potential for STI571 in patients afflicted by this chemoresistant tumor.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Neoplasias Gastrointestinales/etiología , Proteínas Oncogénicas/fisiología , Piperazinas/farmacología , Pirimidinas/farmacología , Células del Estroma , Apoptosis , Benzamidas , División Celular/efectos de los fármacos , Neoplasias Gastrointestinales/metabolismo , Neoplasias Gastrointestinales/patología , Humanos , Mesilato de Imatinib , Mutación , Proteínas Oncogénicas/genética , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-kit , Células Tumorales Cultivadas
12.
Leukemia ; 8(1): 151-5, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8289479

RESUMEN

The erythroid abnormality in patients with myelodysplasia (MDS) is multifactorial, with ineffective erythropoiesis and poor in vitro progenitor response to erythropoietin (EPO). Serum EPO concentration is variable among patients for a given haemoglobin concentration. We studied 19 non-transfusion-dependent patients with MDS, and 13 healthy elderly control subjects in an attempt to define the factors governing variability in serum EPO and to further characterise the anaemia of MDS. Serum EPO concentration was appropriate for the degree of anaemia in 15/19 MDS patients, and was positively related to mean cell volume (MCV), mean cell haemoglobin (MCH), and percentage highly fluorescent reticulocytes (% HFR), but not to absolute or percentage reticulocyte count. Although the observed/predicted ratio for serum transferrin receptor (TfR) concentration was low in 12 of 19 MDS subjects, no relationship to haemoglobin concentration, reticulocytes or serum EPO was seen. Serum TfR was positively correlated with WBC and platelet counts. Serum TfR was higher in patients with sideroblastic anaemia than refractory anaemia. Standardized in vivo p50 was positively correlated to red cell 2,3 diphosphoglycerate concentration, although this was not the only factor influencing the oxygen dissociation curve. We conclude that effective erythroid output responsive to endogenous EPO drive in MDS is positively related to MCV, MCH and % HFR. Serum TfR may not represent effective output as precisely as % HFR, but may be proportional to total marrow erythropoietic activity.


Asunto(s)
Eritropoyesis/fisiología , Eritropoyetina/sangre , Síndromes Mielodisplásicos/sangre , Receptores de Transferrina/metabolismo , Reticulocitos/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Transporte Biológico , Eritropoyetina/uso terapéutico , Humanos , Persona de Mediana Edad , Oxígeno/sangre , Valor Predictivo de las Pruebas , Estudios Prospectivos , Proteínas Recombinantes/sangre , Proteínas Recombinantes/uso terapéutico , Recuento de Reticulocitos , Reticulocitos/citología
13.
Cochrane Database Syst Rev ; (2): CD002290, 2005 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-15846634

RESUMEN

BACKGROUND: Eighty to ninety per cent of children with steroid-sensitive nephrotic syndrome (SSNS) have relapses. About half relapse frequently and are at risk of the adverse effects of corticosteroids. Non-corticosteroid immunosuppressive agents are used to prolong periods of remission in children who relapse frequently. However these non-corticosteroid agents also have significant potential adverse effects. Currently there is no consensus as to the most appropriate second line agent in children who are steroid sensitive, but who continue to relapse. OBJECTIVES: To evaluate the benefits and harms of non-corticosteroid immunosuppressive agents in relapsing SSNS in children. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, reference lists of articles, abstracts from proceedings and contact with known investigators. Search date: August 2004 SELECTION CRITERIA: RCTs or quasi-RCTs were included if they were undertaken in children with relapsing SSNS, if they compared non-corticosteroid agents with placebo, prednisone or no treatment, different doses and/or durations of the same non-corticosteroid agent, different non-corticosteroid agents and outcome data at six months. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as relative risk (RR) with 95% confidence intervals (CI). MAIN RESULTS: Twenty trials involving 923 children were identified. Cyclophosphamide (three trials: RR 0.44, 95% CI 0.26 to 0.73) and chlorambucil (two trials: RR 0.13, 95% CI 0.03 to 0.57) significantly reduced the relapse risk at six to twelve months compared with prednisone alone. In the single chlorambucil versus cyclophosphamide trial, there was no observed difference in relapse risk at two years (RR 1.31, 95% CI 0.80 to 2.13). Cyclosporin was as effective as cyclophosphamide (one trial: RR 1.07, 95% CI 0.48 to 2.35) and chlorambucil (one trial: RR 0.82, 95% CI 0.44 to 1.53) but the effect was not sustained when cyclosporin was ceased. During treatment, levamisole (three trials: RR 0.60, 95% CI 0.45 to 0.79) was more effective than steroids alone but the effect was not sustained. Mizoribine (one trial) and azathioprine (two trials) were no more effective than placebo or prednisone alone in maintaining remission. AUTHORS' CONCLUSIONS: Eight week courses of cyclophosphamide or chlorambucil and prolonged courses of cyclosporin and levamisole reduce the risk of relapse in children with relapsing SSNS compared with corticosteroids alone. Clinically important differences in efficacy among these agents are possible and further comparative trials are still needed.


Asunto(s)
Inmunosupresores/uso terapéutico , Síndrome Nefrótico/tratamiento farmacológico , Adolescente , Niño , Preescolar , Clorambucilo/uso terapéutico , Ciclofosfamida/uso terapéutico , Humanos , Lactante , Levamisol/uso terapéutico , Síndrome Nefrótico/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Prevención Secundaria
14.
Cochrane Database Syst Rev ; (1): CD001533, 2005 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-15674881

RESUMEN

BACKGROUND: In nephrotic syndrome protein leaks from the blood to the urine through the glomeruli resulting in hypoproteinaemia and generalised oedema. While the majority of children with nephrotic syndrome respond to corticosteroids, 70% experience a relapsing course. Corticosteroid usage has reduced the mortality rate to around 3%, however they have known serious adverse effects. OBJECTIVES: To determine the benefits and harms of corticosteroid regimens in preventing relapse in children with steroid sensitive nephrotic syndrome (SSNS). SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Renal Group Specialised Register, MEDLINE and EMBASE without language restriction, reference lists of articles, abstracts from conference proceedings and contact with known investigators. Date of most recent search: October 2004 SELECTION CRITERIA: Randomised controlled trials performed in children (three months to 18 years) in their initial or subsequent episode of SSNS, comparing different durations, total doses or other dose strategies using any corticosteroid agent, with outcome data at six months or more. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as relative risk (RR) with 95% confidence intervals (CI).Meta-regression was used to explore potential between-study differences due to baseline risk of relapse, study quality and interventions. MAIN RESULTS: Nineteen trials were identified. Six trials comparing two months of prednisone with three months or more in the first episode showed longer duration significantly reduced the risk of relapse at 12 to 24 months (RR 0.70; 95% CI 0.58 to 0.84). There was an inverse linear relationship between treatment duration and risk of relapse (RR = 1.26 - 0.112 duration; P = 0.03). There was a significant reduction in the number of frequent relapsers and the mean relapse rate/patient/year. Deflazacort was significantly more effective in maintaining remission than prednisone in children who frequently relapsed (RR 0.44; 95% CI 0.25 to 0.78). There were no increases in adverse events. AUTHORS' CONCLUSIONS: Children in their first episode of SSNS should be treated for at least three months with an increase in benefit being demonstrated for up to seven months of treatment For a baseline risk for relapse following the first episode of 60% with two months of prednisone, daily prednisone for four weeks followed by alternate-day therapy for six months would reduce the number of children relapsing by 33%. Deflazacort deserves further study for frequent relapsers.


Asunto(s)
Antiinflamatorios/uso terapéutico , Glucocorticoides/uso terapéutico , Síndrome Nefrótico/tratamiento farmacológico , Adolescente , Niño , Preescolar , Glucocorticoides/efectos adversos , Humanos , Lactante , Prednisona/uso terapéutico , Pregnenodionas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Prevención Secundaria
15.
Psychopharmacology (Berl) ; 136(2): 201-4, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9551778

RESUMEN

In a placebo-controlled double-blind trial 308 smokers were individually randomly allocated to one of four groups: 1) 3 g dextrose tablets and 15 mg nicotine transdermal patch; 2) dextrose and placebo patch; 3) placebo tablets and nicotine patch; 4) placebo tablets and placebo patch. Patients were scheduled to attend weekly smokers clinic sessions starting 1 week before the quit date and continue for 4 weeks after that date. The primary outcome variable was biochemically verified abstinence at the final session, four weeks after the scheduled quit date. The proportion of smokers abstinent in the four groups was as follows: 49% - dextrose plus active patch; 44% - dextrose plus placebo patch; 36% - placebo tablet plus active patch; 30% - placebo tablet plus placebo patch. The difference between the dextrose and placebo tablets (13%) was statistically significant (P < 0.01, one-tailed); the difference between the active and placebo patches (6%) was not. There was no significant difference between the effect of the dextrose when accompanied by active versus placebo patches. There was no significant effect of dextrose on weight. The results suggest that dextrose supplementation to the diet may be a cheap and simple aid to giving up smoking. Further research is now needed to establish its long-term efficacy.


Asunto(s)
Glucosa/administración & dosificación , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Cese del Hábito de Fumar , Adolescente , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cese del Hábito de Fumar/psicología
16.
Ann N Y Acad Sci ; 916: 1-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11193608

RESUMEN

The OIE (Office International des Epizooties), the world animal health organization, has been addressing the most serious animal diseases throughout the globe for the past 75 years. It has developed guidelines for safe international trade in animals and animal products as part of its original mandate. Since the establishment of the World Trade Organization and the Sanitary and Phytosanitary Agreement, the role for the OIE has changed. At this point in the history of the OIE, new demands, expectations and challenges lie ahead as the OIE faces a new role in international trade.


Asunto(s)
Enfermedades de los Animales/epidemiología , Enfermedades de los Animales/prevención & control , Bienestar del Animal/normas , Comercio , Agencias Internacionales , Animales , Guías como Asunto
17.
Clin Chim Acta ; 150(3): 213-20, 1985 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-4064328

RESUMEN

Blood oxygen content calculated from haemoglobin concentration, measured haemoglobin oxygen saturation and measured oxygen tension was compared with three other methods of estimating oxygen content. These other methods were those of Van Slyke and Zander, which are direct methods, and a method using Kelman's equation to estimate the saturation from measured oxygen tension and hence content. The coefficients of correlation (corr coeff) (r) were 0.9050 (n = 22), 0.9919 (n = 24) and 0.9862 (n = 25) for the respective methods when compared with oxygen content calculated using measured saturation. The Van Slyke method proved to be imprecise in our hands. The direct measurement using the oxygen cuvette of Zander gave oxygen content values similar to those estimated from measured saturation. The oxygen content calculated from pO2 alone when compared to that derived from measured saturation had a corr coeff (r) of 0.9862 (n = 25), but the high residual standard deviation (So) of 6.939 ml/l indicates that the practice of calculating oxygen content from oxygen tension alone is imprecise. We conclude that oxygen content may be satisfactorily estimated by the Zander method when it becomes generally available, but until then the measurement of oxygen saturation is a necessary prerequisite to the estimation of blood oxygen content.


Asunto(s)
Oxígeno/sangre , Hemoglobinas/análisis , Humanos , Matemática , Métodos , Presión Parcial
18.
Clin Chim Acta ; 132(2): 127-32, 1983 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-6616868

RESUMEN

Plasma pyruvate kinase (PK) and creatine kinase (CK) were measured in healthy subjects engaging in (a) mild exercise, 30 min on an exercise cycle maintaining a pulse rate of 150/min, (b) moderate exercise, squeezing a ball until exhaustion with a sphygmomanometer cuff inflated above systolic pressure around the arm (max. 2 min) and (c) severe exercise, completing a marathon race. Mild exercise resulted in no change in enzyme levels over 24 h. Moderate exercise produced a small increase in PK but no change in CK. PK activity rose from 35.3 +/- 10 U/l pre-exercise to 41.3 +/- 13 U/l 15 min post-exercise (n = 8, p less than 0.025). Severe exercise (completing a marathon race) resulted in a 3-fold increase in PK from 26 (4-87) U/l pre-race to 69 (21-156) U/l immediately post-race, and also, as expected, an increase in CK from 60 (15-164) U/l to 257 (72-1535) U/l (results are means and ranges, n = 69, p less than 0.001 for both enzymes). Runners showed parallel increases in PK and CK (p less than 0.05 by Spearman rank correlation). The mean post-race activity of CK-MB was less than 5% of total CK but 18 runners had values greater than 6% (mean 4.8, range 1-18). We conclude that PK, like CK, is increased following exercise due to liberation of muscle enzyme. However, only severe exercise is likely to lead to a substantial increase in plasma PK activity and therefore prejudice its clinical usefulness as a diagnostic test.


Asunto(s)
Creatina Quinasa/sangre , Esfuerzo Físico , Piruvato Quinasa/sangre , Adolescente , Adulto , Humanos , Isoenzimas , Masculino , Persona de Mediana Edad , Carrera
19.
Neurosurgery ; 7(4): 326-36, 1980 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7442975

RESUMEN

Nine patients whose history suggested increased intracranial pressure (ICP), but whose funduscopic examination did not reveal papilledema, are described. Cerebrospinal fluid monitoring in seven of the cases showed abnormal pressure waves ranging from 22 to 40 mm Hg. The findings of computed tomography and isotope cisternography and the response to therapy supported the clinical diagnosis of benign intracranial hypertension (BIH). Fluorescein angiography, which was performed in five cases, was normal. None of the patients had enlargement of the blind spot; all had normal intraocular pressure. The clinical spectrum of BIH may need to be enlarged to include cases of increased ICP without clinically evident papilledema. (Neurosurgery, 7: 326-336, 1980).


Asunto(s)
Presión Intracraneal , Papiledema/complicaciones , Seudotumor Cerebral/diagnóstico , Adolescente , Adulto , Femenino , Angiografía con Fluoresceína , Humanos , Presión Intraocular , Masculino , Monitoreo Fisiológico , Seudotumor Cerebral/complicaciones , Seudotumor Cerebral/terapia , Tomografía Computarizada por Rayos X , Trastornos de la Visión/etiología
20.
Cochrane Database Syst Rev ; (4): CD002290, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11687155

RESUMEN

BACKGROUND: Eighty to ninety per cent children with steroid sensitive nephrotic syndrome (SSNS) have one or more relapses. About half of these children relapse frequently and are at risk of the adverse effects of corticosteroids. Non-corticosteroid immunosuppressive agents are used to prolong periods of remission in children, who relapse frequently. However these non-corticosteroid agents also have significant potential adverse effects. Currently there is no consensus as to the most appropriate second line agent in children who are steroid sensitive, but who continue to relapse. In this systematic review of randomised controlled trials (RCTs), the benefits and harms of these immunosuppressive agents are evaluated. OBJECTIVES: To evaluate the benefits and harms of non-corticosteroid immunosuppressive agents in relapsing SSNS in children. SEARCH STRATEGY: Published and unpublished randomised controlled trials were identified from the Cochrane Controlled Trials Register, MEDLINE, EMBASE, reference lists of articles, abstracts from proceedings and contact with known investigators in the area. SELECTION CRITERIA: Randomised or quasi-randomised trials were included if they were carried out in children (aged three months to 18 years) with relapsing SSNS, if they compared non-corticosteroid agents with placebo, prednisone or no treatment, different doses and/ or durations of the same non-corticosteroid agent, different non-corticosteroid agents and if they had outcome data at six months or more. DATA COLLECTION AND ANALYSIS: Two reviewers independently reviewed all eligible studies for inclusion, assessed study quality and extracted data. The principle outcome measure was the number of children with and without relapse after six and 12 to 24 months. Secondary outcomes sought were the mean time to next relapse, the mean number of relapses per year and adverse events. A random effects model was used to estimate summary effect measures after testing for heterogeneity. Examination of possible between-study differences due to study quality, different interventions and different populations was attempted by subgroup analysis. MAIN RESULTS: Eighteen trials involving 828 children were identified. Cyclophosphamide (three trials; relative risk (RR) 0.44; 95% confidence intervals (95% CI) 0.26 to 0.73) and chlorambucil (two trials; RR 0.13; 95% CI 0.03 to 0.57) significantly reduced the relapse risk at six to twelve months compared with prednisone alone. In the single chlorambucil versus cyclophosphamide trial, there was no observed difference in relapse risk at two years (RR 1.31; 95% CI 0.80 to 2.13). Cyclosporin was as effective as cyclophosphamide (one trial, RR 1.07; 95% CI 0.48 to 2.35) and chlorambucil (one trial, RR 0.82; 95% CI 0.44 to 1.53) but the effect was not sustained when cyclosporin was ceased. During treatment levamisole (three trials, RR 0.60; 95% CI 0.45 to 0.79) was more effective than steroids alone but the effect was not sustained. Mizoribine (one trial) and azathioprine (two trials) were no more effective than placebo or prednisone alone in maintaining remission. REVIEWER'S CONCLUSIONS: Eight weeks courses of cyclophosphamide or chorambucil and prolonged courses of cyclosporin and levamisole reduce the risk of relapse in children with relapsing SSNS compared with corticosteroids alone. Clinically important differences in efficacy among these agents are possible and further comparative trials are still needed. Meanwhile choice between these agents depends on physician and patient preferences related to therapy duration and the type and frequency of complications.


Asunto(s)
Inmunosupresores/uso terapéutico , Síndrome Nefrótico/tratamiento farmacológico , Adolescente , Niño , Preescolar , Clorambucilo/uso terapéutico , Ciclofosfamida/uso terapéutico , Humanos , Lactante , Levamisol/uso terapéutico , Recurrencia
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