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1.
J Endocrinol Invest ; 46(12): 2583-2599, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37286863

RESUMEN

PURPOSE/METHODS: The determination of tumour biomarkers is paramount to advancing personalized medicine, more so in rare tumours like medullary thyroid carcinoma (MTC), whose diagnosis is still challenging. The aim of this study was to identify non-invasive circulating biomarkers in MTC. To achieve this goal, paired MTC tissue and plasma extracellular vesicle samples were collected from multiple centres and microRNA (miRNA) expression levels were evaluated. RESULTS: The samples from a discovery cohort of 23 MTC patients were analysed using miRNA arrays. Lasso logistic regression analysis resulted in the identification of a set of circulating miRNAs as diagnostic biomarkers. Among them, miR-26b-5p and miR-451a, were highly expressed and their expression decreased during follow-up in disease-free patients in the discovery cohort. Circulating miR-26b-5p and miR-451a were validated using droplet digital PCR in a second independent cohort of 12 MTC patients. CONCLUSION: This study allowed the identification and validation of a signature of two circulating miRNAs, miR-26b-5p and miR-451a, in two independent cohorts reporting a significant diagnostic performance for MTC. The results of this study offer advancements in molecular diagnosis of MTC proposing a novel non-invasive tool to use in precision medicine.


Asunto(s)
MicroARN Circulante , MicroARNs , Neoplasias de la Tiroides , Humanos , MicroARNs/genética , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Biomarcadores , Biomarcadores de Tumor/metabolismo
2.
J Biol Regul Homeost Agents ; 34(3): 977-986, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32664712

RESUMEN

Chlamydia trachomatis, the leading cause of bacterial sexually transmitted diseases worldwide, can disseminate and localize to the upper genital tract impairing reproductive function. Specifically, ascending C. trachomatis genital infection has been demonstrated to cause epididymitis or epididymo-orchitis, well-known risk factors for male infertility. C. trachomatis possesses the ability to infect primary human Sertoli cells, key elements for the spermatogenetic process and the immune protection of germ cells. Therefore, herein, we investigated the innate immune response in Sertoli cells following C. trachomatis infection, as well as its indirect effects on human spermatozoa. Specifically, we evaluated C. trachomatis mediated induction of Toll-like Receptors (TLR) 2, 3 and 4 as well as of downstream intracellular signaling molecules (NFκB and IRF3) and the levels of the related inflammatory mediators (IL-1α, IL-6, IFN-α, IFN-ß and IFN-γ), in an in vitro infection model of primary human Sertoli cells. The main result of our study shows that C. trachomatis induced TLR3-mediated recognition in human Sertoli cells, accompanied by the down-modulation of NFκB and IRF3-dependent signaling pathways followed by no production of pro-inflammatory cytokines. In conclusion, our findings suggest that C. trachomatis can disrupt the innate immune response in Sertoli cells and evade intracellular killing, potentially giving rise to a long-term infection that may exert negative effects on the male reproductive system.


Asunto(s)
Chlamydia trachomatis , Factor 3 Regulador del Interferón/metabolismo , FN-kappa B/metabolismo , Células de Sertoli/microbiología , Transducción de Señal , Receptor Toll-Like 3/metabolismo , Células Cultivadas , Infecciones por Chlamydia , Humanos , Interferones/metabolismo , Interleucinas/metabolismo , Masculino , Células de Sertoli/metabolismo
4.
Neuropathol Appl Neurobiol ; 44(7): 687-706, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29478280

RESUMEN

AIMS: Paediatric low-grade gliomas (pLGGs) are a heterogeneous group of brain tumours associated with a high overall survival: however, they are prone to recur and supratentorial lesions are difficult to resect, being associated with high percentage of disease recurrence. Our aim was to shed light on the biology of pLGGs. METHODS: We performed microRNA profiling on 45 fresh-frozen grade I tumour samples of various histological classes, resected from patients aged ≤16 years. We identified 93 microRNAs specifically dysregulated in tumours as compared to non-neoplastic brain tissue. Pathway analysis of the microRNAs signature revealed PI3K/AKT signalling as one of the centrally enriched oncogenic signalling. To date, activation of the PI3K/AKT pathway in pLGGs has been reported, although activation mechanisms have not been fully investigated yet. RESULTS: One of the most markedly down-regulated microRNAs in our supratentorial pLGGs cohort was miR-139-5p, whose targets include the gene encoding the PI3K's (phosphatidylinositol 3-kinase) catalytic unit, PIK3CA. We investigated the role of miR-139-5p in regulating PI3K/AKT signalling by the use of human cell cultures derived from supratentorial pLGGs. MiR-139-5p overexpression inhibited pLGG cell proliferation and decreased the phosphorylation of PI3K target AKT and phosphorylated-p70 S6 kinase (p-p70 S6K), a hallmark of PI3K/AKT/mTORC1 signalling activation. The effect of miR-139-5p was mediated by PI3K inhibition, as suggested by the decrease in proliferation and phosphorylation of AKT and p70 S6K after treatment with the direct PI3K inhibitor LY294002. CONCLUSIONS: These findings provide the first evidence that down-regulation of miR-139-5p in supratentorial pLGG drives cell proliferation by derepressing PI3K/AKT signalling.


Asunto(s)
Proliferación Celular/genética , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Glioma/genética , MicroARNs/genética , Transducción de Señal/genética , Neoplasias Supratentoriales/genética , Adolescente , Niño , Preescolar , Femenino , Glioma/metabolismo , Glioma/patología , Humanos , Lactante , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , MicroARNs/metabolismo , Clasificación del Tumor , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Supratentoriales/metabolismo , Neoplasias Supratentoriales/patología
5.
J Clin Pharm Ther ; 38(1): 36-40, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23167633

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: In analgesic trials, pain relief is often assessed using a pain-relief score. We aimed to assess, through a meta-analysis, whether absence of need for rescue medication (NNR) is a reliable outcome measure in the evaluation of acute pain relief. METHODS: Individual-patient meta-analysis of placebo-controlled trials of single-dose naproxen sodium 220 or 440 mg in dental pain. Efficacy estimates were based on NNR and compared with the more commonly used 50% maximum total pain relief score (50% TOTPAR). The trials included were the full set of trials sponsored by one manufacturer. RESULTS AND DISCUSSION: Need for rescue medication and 50% TOTPAR gave comparable estimates of efficacy of naproxen sodium (220 and 440 mg) relative to placebo in dental pain at both 8 and 12 h after dosing. WHAT IS NEW AND CONCLUSION: No need for rescue medication is a reliable outcome measure for use in acute pain trials. As it is more readily understandable than 50% TOTPAR, it should be the preferred primary outcome measure in acute pain trials.


Asunto(s)
Analgésicos/uso terapéutico , Naproxeno/uso terapéutico , Dolor/tratamiento farmacológico , Analgésicos/administración & dosificación , Ensayos Clínicos Controlados como Asunto , Relación Dosis-Respuesta a Droga , Humanos , Naproxeno/administración & dosificación , Evaluación de Resultado en la Atención de Salud , Dolor/etiología , Reproducibilidad de los Resultados , Factores de Tiempo
7.
J Clin Pharm Ther ; 36(2): 125-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21366639

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Pharmacogenetic studies, to help us understand variability in human drug response, have hitherto focussed largely on our own germline mutations, and in the context of anticancer and antimicrobial drugs, also on mutations of the tumour cell or invader microorganism. Here, we wish to draw attention to how our microbiome may contribute to variability in drug effects. COMMENT: Irinotecan, a prodrug which is activated to the topoisomerase I inhibitory metabolite (SN-38), is commonly used for the treatment of a range of cancers. SN-38 is subsequently detoxified by uridine diphosphate-glycosyltransferase 1, encoded by the UGT1A1 gene. It is well known that the variant allele UGT1A*18 is associated with the more common adverse effects of irinotecan. A recent study shows that the potentially dose-limiting irinotecan-induced diarrhoea is due to enterohepatic circulation of SN-38, and its reactivation in the gut by bacterial ß-glucuronidases. Importantly, the authors used specific inhibitors of the microbial enzymes to reduce the gastro-intestinal toxicity in mice. WHAT IS NEW AND CONCLUSION: We draw attention to the increasing range of diseases, including diabetes and obesity, associated with our microbiome. This pharmacogenetic example reminds us that in personalized medicine, there is more than our own genome to take account of.


Asunto(s)
Antineoplásicos Fitogénicos/efectos adversos , Camptotecina/análogos & derivados , Glucuronidasa/metabolismo , Glucuronosiltransferasa/genética , Neoplasias/tratamiento farmacológico , Inhibidores de Topoisomerasa I/efectos adversos , Animales , Antineoplásicos Fitogénicos/metabolismo , Antineoplásicos Fitogénicos/uso terapéutico , Bacterias/enzimología , Camptotecina/efectos adversos , Camptotecina/metabolismo , Camptotecina/uso terapéutico , Diarrea/inducido químicamente , Inhibidores Enzimáticos/farmacología , Glucuronidasa/antagonistas & inhibidores , Glucuronosiltransferasa/metabolismo , Humanos , Irinotecán , Ratones , Neoplasias/genética , Farmacogenética , Polimorfismo Genético , Profármacos/efectos adversos , Profármacos/metabolismo , Profármacos/uso terapéutico , Inhibidores de Topoisomerasa I/uso terapéutico
8.
J Alcohol Drug Educ ; 54(1): 56-75, 2010 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20730023

RESUMEN

This qualitative study examined the drug resistance strategies of Hawaiian youth residing in rural communities in Hawai`i. Forty seven youth participated in 14 focus groups which focused on the social and environmental context of drug use for these youth. The findings indicated that there were 47 references to resistance strategies used in drug offer situations. These strategies fell within two different categories: (1) overt/confrontational drug resistance strategies, and (2) non-confrontational drug resistance strategies. These strategies occurred within the community context of relational networks of ascribed and biological family members, and differed in frequency of use by gender. Implications for culturally grounded drug prevention programs for rural Hawaiian youth are discussed.

9.
J Ethn Subst Abuse ; 8(2): 163-77, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19459123

RESUMEN

This exploratory, qualitative study examined the community-based risk and resiliency factors related to the drug use of rural Native Hawaiian youth. Forty-seven youth from five middle schools participated in focus groups that examined the ecological context of drug use for rural Hawaiian youth. Findings indicated that youth in the study were part of large extended networks of families and that these networks became a defining characteristic of the rural communities in the study. These familial networks functioned as sources of risk and protection related to drug use for youth participants. Implications for community-based practice are discussed.


Asunto(s)
Relaciones Familiares , Resiliencia Psicológica , Trastornos Relacionados con Sustancias/etnología , Niño , Femenino , Grupos Focales , Hawaii/epidemiología , Humanos , Masculino , Factores de Riesgo , Población Rural , Apoyo Social , Estudiantes/psicología , Trastornos Relacionados con Sustancias/epidemiología
10.
J Ethn Cult Divers Soc Work ; 18(3): 242-258, 2009 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20352019

RESUMEN

This qualitative study examined how Native Hawaiian youth from rural communities utilized cultural practices to promote drug resistance and/or abstinence. Forty-seven students from 5 different middle schools participated in gender specific focus groups that focused on the cultural and environmental contexts of drug use for Native Hawaiian youth. The findings described culturally specific activities that participants used in drug related problem situations. The findings also suggested that those youth with higher levels of enculturation were able to resist drugs more effectively than those youth who were disconnected from their culture. The implications of these findings for social work practice are discussed.

11.
J Clin Endocrinol Metab ; 93(10): 4080-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18664540

RESUMEN

CONTEXT: Notch genes encode receptors for a signaling pathway that regulates cell growth and differentiation in various contexts, but the role of Notch signaling in thyroid follicular cells has never been fully published. OBJECTIVE: The objective of the study was to characterize the expression of Notch pathway components in thyroid follicular cells and Notch signaling activities in normal and transformed thyrocytes. DESIGN/SETTING AND PATIENTS: Expression of Notch pathway components and key markers of thyrocyte differentiation was analyzed in murine and human thyroid tissues (normal and tumoral) by quantitative RT-PCR and immunohistochemistry. The effects of Notch overexpression in human thyroid cancer cells and FTRL-5 cells were explored with analysis of gene expression, proliferation assays, and experiments involving transfection of a luciferase reporter construct containing human NIS promoter regions. RESULTS: Notch receptors are expressed during the development of murine thyrocytes, and their expression levels parallel those of thyroid differentiation markers. Notch signaling characterized also normal adult thyrocytes and is regulated by TSH. Notch pathway components are variably expressed in human normal thyroid tissue and thyroid tumors, but expression levels are clearly reduced in undifferentiated tumors. Overexpression of Notch-1 in thyroid cancer cells restores differentiation, reduces cell growth rates, and stimulates NIS expression via a direct action on the NIS promoter. CONCLUSION: Notch signaling is involved in the determination of thyroid cell fate and is a direct regulator of thyroid-specific gene expression. Its deregulation may contribute to the loss of differentiation associated with thyroid tumorigenesis.


Asunto(s)
Biomarcadores/metabolismo , Carcinoma Papilar/genética , Diferenciación Celular/genética , Receptores Notch/fisiología , Glándula Tiroides/metabolismo , Neoplasias de la Tiroides/genética , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/metabolismo , Animales , Carcinoma Papilar/metabolismo , Desdiferenciación Celular/genética , Células Cultivadas , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Especificidad de Órganos/genética , Receptores Notch/genética , Transducción de Señal/genética , Transducción de Señal/fisiología , Simportadores/genética , Simportadores/metabolismo , Glándula Tiroides/citología , Glándula Tiroides/embriología , Neoplasias de la Tiroides/metabolismo
12.
Oncogene ; 25(55): 7267-73, 2006 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-16878160

RESUMEN

Medulloblastoma (MB) results from aberrant development of cerebellar neurons in which altered hedgehog (Hh) signalling plays a major role. We investigated the possible influence of Hh signalling on ErbB-receptor expression in MB, in particular that of the ErbB-4 CYT-1 and CYT-2 isoforms generated by alternative splicing of the cytoplasmic domain. ErbB-4 expression was downregulated in Hh-induced MBs from Patched-1(+/-) mice. Hh signalling (reflected by enhanced expression of the Gli1 transcription factor) inhibited ErbB-4 expression in mouse cerebellar granule progenitors and human MB cells. Analysis of 26 human primary MBs revealed a subset of 11 tumors characterized by low Gli1 levels, upregulated ErbB-4 expression and increased CYT-1:CYT-2 ratios. Interestingly, CYT-1 and Gli1 levels were inversely correlated. ErbB-4 CYT-1 and CYT-2 had different phenotypic effects in cultured MB cells: in response to neuregulin treatment, CYT-2 overexpression inhibited proliferation whereas CYT-1, which includes a phosphatidylinositol 3-kinase (PI3K)-binding site that is missing in CYT-2, enhanced resistance to starvation- and etoposide-induced apoptosis by activating PI3K/Akt signalling. CYT-1:CYT-2 ratios displayed correlation with tumor histotype and ErbB-2 levels, which are established prognostic indices for MB. These findings demonstrate that low-level Hh signalling in human MB is associated with the selective maintenance of high ErbB-4 CYT-1 expression, an alteration that exerts tumor-promoting effects.


Asunto(s)
Empalme Alternativo , Citoplasma/metabolismo , Receptores ErbB/metabolismo , Proteínas Hedgehog/metabolismo , Meduloblastoma/clasificación , Transducción de Señal , Animales , Secuencia de Bases , Cartilla de ADN , Humanos , Meduloblastoma/metabolismo , Meduloblastoma/patología , Ratones , Pronóstico , Receptor ErbB-4 , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
Oncogene ; 36(32): 4641-4652, 2017 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-28368412

RESUMEN

Aberrant Hedgehog/GLI signaling has been implicated in a diverse spectrum of human cancers, but its role in lung adenocarcinoma (LAC) is still under debate. We show that the downstream effector of the Hedgehog pathway, GLI1, is expressed in 76% of LACs, but in roughly half of these tumors, the canonical pathway activator, Smoothened, is expressed at low levels, possibly owing to epigenetic silencing. In LAC cells including the cancer stem cell compartment, we show that GLI1 is activated noncanonically by MAPK/ERK signaling. Different mechanisms can trigger the MAPK/ERK/GLI1 cascade including KRAS mutation and stimulation of NRP2 by VEGF produced by the cancer cells themselves in an autocrine loop or by stromal cells as paracrine cross talk. Suppression of GLI1, by silencing or drug-mediated, inhibits LAC cells proliferation, attenuates their stemness and increases their susceptibility to apoptosis in vitro and in vivo. These findings provide insight into the growth of LACs and point to GLI1 as a downstream effector for oncogenic pathways. Thus, strategies involving direct inhibition of GLI1 may be useful in the treatment of LACs.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Células Madre Neoplásicas/metabolismo , Proteína con Dedos de Zinc GLI1/metabolismo , Adenocarcinoma/patología , Animales , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Pulmonares/patología , Ratones , Ratones SCID , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Células Madre Neoplásicas/patología , Neuropilina-2/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Piridinas/farmacología , Pirimidinas/farmacología , Interferencia de ARN/fisiología , ARN Interferente Pequeño/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína con Dedos de Zinc GLI1/antagonistas & inhibidores , Proteína con Dedos de Zinc GLI1/genética
15.
Health Technol Assess ; 10(7): iii, ix-118, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16545206

RESUMEN

OBJECTIVES: To examine the clinical effectiveness and cost-effectiveness of newer antiepileptic drugs (AEDs) for epilepsy in children: gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine, topiramate and vigabatrin. DATA SOURCES: Electronic databases. Drug company submissions. REVIEW METHODS: For the systematic review of clinical and cost-effectiveness, studies were assessed for inclusion according to predefined criteria. Data extraction and quality assessment were also undertaken. A decision-analytic model was constructed to estimate the cost-effectiveness of the newer agents in children with partial seizures, the only condition where there were sufficient trial data to inform a model. RESULTS: The quality of the randomised controlled trial (RCT) data was generally poor. For each of the epilepsy subtypes considered in RCTs identified for this review (partial epilepsy with or without secondary generalisation, Lennox-Gastaut syndrome, infantile spasms, absence epilepsy and benign epilepsy with centrotemporal spikes), there is some evidence from placebo-controlled trials that the newer agents tested are of some value in the treatment of these conditions. Where active controls have been used, the limited evidence available does not indicate a difference in effectiveness between newer and older drugs. The data are not sufficient to inform a prescribing strategy for any of the newer agents in any of these conditions. In particular, there is no clinical evidence to suggest that the newer agents should be considered as a first-choice treatment in any form of epilepsy in children. Annual drug costs of the newer agents ranges from around 400 pound to 1200 pound, depending on age and concomitant medications. An AED that is ineffective or has intolerable side-effects will only be used for a short period of time, and many patients achieving seizure freedom will successfully withdraw from drug treatment without relapsing. The results of the decision-analytic model do not suggest that the use of the newer agents in any of the scenarios considered is clearly cost-effective but, similarly, do not indicate that they are clearly not cost-effective. CONCLUSIONS: The prognosis for children diagnosed with epilepsy is generally good, with a large proportion responding well to the first treatment given. A substantial proportion, however, will not respond well to treatment, and for these patients the clinical goal is to find an optimal balance between the benefits and side-effects of any treatment given. For the newly, or recently, diagnosed population, the key question for the newer drugs is how soon they should be tried. The cost-effectiveness of using these agents early, in place of one of the older agents, will depend on the effectiveness and tolerability of these agents compared with the older agents; the evidence from the available trial data so far suggests that the newer agents are no more effective but may be somewhat better tolerated than the older agents, and so the cost-effectiveness for early use will depend on the trade-off between effectiveness and tolerability, both in terms of overall (long-term) treatment retention and overall utility associated with effects on seizure rate and side-effects. There are insufficient data available to estimate accurately the nature of this trade off either in terms of long-term treatment retention or utility. Better information is required from RCTs before any rational evidence-based prescribing strategy could be developed. Ideally, RCTs should be conducted from a 'public health' perspective, making relevant comparisons and incorporating outcomes of interest to clinicians and patients, with sufficiently long-term follow-up to determine reliably the clinical utility of different treatments, particularly with respect to treatment retention and the balance between effectiveness and tolerability. RCTs should mirror clinical practice with respect to diagnosis, focusing on defined syndromes or, where no syndrome is identified, on groups defined by specific seizure type(s) and aetiology. Epilepsy in children is a complex disease, with a variety of distinct syndromes and many alternative treatment options and outcomes. Diagnosis-specific decision-analytic models are required; further research may be required to inform parameter values adequately with respect to epidemiology and clinical practice.


Asunto(s)
Anticonvulsivantes/economía , Anticonvulsivantes/uso terapéutico , Análisis Costo-Beneficio , Epilepsia/tratamiento farmacológico , Resultado del Tratamiento , Anticonvulsivantes/clasificación , Niño , Epilepsia/economía , Humanos , Años de Vida Ajustados por Calidad de Vida
16.
Biochem Pharmacol ; 47(7): 1121-6, 1994 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-8161340

RESUMEN

In vitro absorption of three angiotensin converting enzyme (ACE) inhibitors, captopril, enalapril and lisinopril, and their stabilities in aqueous buffer as well as their resistance to intestinal and dermal tissue homogenates were investigated. The results demonstrate that the spontaneous oxidation of captopril, enalapril and lisinopril followed first-order degradation kinetics in McIlvaine's citrate-phosphate buffer. The degradation rates for enalapril and lisinopril were much slower than that for captopril. With the former two ACE inhibitors, the first-order rate constants of breakdown in the presence of dermal homogenate were not significantly different from the control values. Intestinal homogenate increased the decomposition of both of these inhibitors when compared to the enzyme-free control systems. On the other hand, the first-order rates of disappearance of captopril in the presence of both dermal and intestinal homogenates were lower than in the enzyme-free system. The extent of reduction was proportional to the amount of homogenate added. This suggests that tissue homogenates prevent the oxidation of captopril to its disulphide dimer. Transport experiments show that the amounts of ACE inhibitors transferred from solution on the mucosal side increased linearly with incubation time over the 2 hr of study. The rates of transfer from the mucosal side to the serosal side had the following rank order: captopril > enalapril > lisinopril roughly in the ratio 1:1.13:1.27. Addition of harmaline caused a significant reduction in the transfer rate of captopril compared to the control system, which strongly suggests that captopril is transported by a sodium-dependent carrier-mediated process across intestinal tissue.


Asunto(s)
Captopril/metabolismo , Enalapril/metabolismo , Absorción Intestinal , Lisinopril/metabolismo , Animales , Transporte Biológico Activo , Estabilidad de Medicamentos , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Cinética , Ratas , Ratas Wistar , Piel/metabolismo
17.
APMIS ; 107(6): 585-92, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10379686

RESUMEN

The purpose of this study was to compare resistance and cross-resistance development in Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients to commonly used antipseudomonal antibiotics. Isolates were repeatedly exposed to subinhibitory concentrations of either azlocillin, tobramycin, ceftazidime or ciprofloxacin. On 10 consecutive occasions, samples were removed from the half-MIC well of a microtitre plate and regrown in drug-free medium to provide the next inoculum for MIC determination. The increase in MIC at the end of the treatment period was significant (p<0.05) for all selecting antibiotics. Cross-resistance to unrelated antibiotics was not observed, but was significant (p<0.05) in all beta-lactams (ticarcillin, piperacillin, ceftazidime and cefsulodin) studied where azlocillin was the selecting antibiotic. The addition of clavulanic acid to ticarcillin and of tazobactam to piperacillin had no effect on cross-resistance. The development of resistance to azlocillin was associated with increased beta-lactamase activity and a change in isoelectric point of the beta-lactamases. The result of this study supports a rotational policy for antipseudomonal antibiotics in CF patients.


Asunto(s)
Fibrosis Quística/complicaciones , Infecciones por Pseudomonas/complicaciones , Pseudomonas aeruginosa/efectos de los fármacos , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Azlocilina/farmacología , Ceftazidima/farmacología , Cefalosporinas/farmacología , Ciprofloxacina/farmacología , Fibrosis Quística/microbiología , Farmacorresistencia Microbiana , Humanos , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Penicilinas/farmacología , Infecciones por Pseudomonas/microbiología , Tobramicina/farmacología
18.
Drug Saf ; 24(11): 793-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11665867

RESUMEN

One of the most difficult tasks in the evaluation of a medicine is whether it causes a particular rare and unusual (idiosyncratic) adverse effect. Such causality assessments are sometimes done by drug de-challenge and re-challenge. When the adverse effect is potentially serious, there is clearly an important decision to be made as to whether the re-challenge is justifiable and hence ethical. The recent controversy about the potential cardiotoxicity of fexofenadine, the fatalities associated with penicillin re-challenge and the fatalities associated with abacavir re-challenge highlight some of the potential serious risks of drug re-challenge. The associated important ethical issues are discussed. In particular, there is the need to ensure respect for the patient and to consider the scientific and social value of the re-challenge. A framework for evaluating and assessing the appropriateness of a particular drug re-challenge is proposed in the light of recent as well as long-standing discussions of drug re-challenge, patient informed consent and the ethics of human experimentation, in general. It is suggested that a drug re-challenge should be approached with the same rigour and standards of documentation as are currently required of clinical trials. Given the potential conflicts of interest inherent with any drug study, it is argued that the safeguards, as may be provided by scrutiny by an ethics committee, are necessary for a drug re-challenge. For the investigator contemplating the conduct of a drug re-challenge we would recommend the following: (i) a careful risk-benefit assessment as part of the decision-making process; (ii) careful scientific preparation, including appropriate expert support and emergency back-up facilities, if re-challenge is deemed necessary; (iii) the writing of a detailed protocol for independent approval and for safeguarding all concerned; and (iv) meticulous record keeping.


Asunto(s)
Hipersensibilidad a las Drogas/etiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Ética Médica , Causalidad , Ensayos Clínicos como Asunto , Toma de Decisiones , Hipersensibilidad a las Drogas/epidemiología , Inglaterra/epidemiología , Humanos , Consentimiento Informado , Selección de Paciente , Vigilancia de Productos Comercializados , Medición de Riesgo
19.
Health Technol Assess ; 4(37): 1-191, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11134919

RESUMEN

BACKGROUND: Atopic eczema is the commonest inflammatory skin disease of childhood, affecting 15-20% of children in the UK at any one time. Adults make up about one-third of all community cases. Moderate-to-severe atopic eczema can have a profound effect on the quality of life for both sufferers and their families. In addition to the effects of intractable itching, skin damage, soreness, sleep loss and the social stigma of a visible skin disease, other factors such as frequent visits to doctors, special clothing and¿the need to constantly apply messy topical applications all add to the burden of disease. The cause of atopic eczema is unknown, though a genetic pre-disposition and a combination of allergic and non-allergic factors appear to be important in determining disease expression. Treatment of atopic eczema in the UK is characterised by a profusion of treatments aimed at disease control. The evidential basis of these treatments is often unclear. Most people with atopic eczema are managed in primary care where the least research has been done. OBJECTIVES: The objectives of this scoping review are two-fold. To produce an up-to-date coverage 'map' of randomised controlled trials (RCTs) of treatments of atopic eczema. To assist in making treatment recommendations by summarising the available RCT evidence using qualitative and quantitative methods. DATA SOURCES: Data sources included electronic searching of MEDLINE, EMBASE, the Cochrane Controlled Clinical Trials Register, the Cochrane Skin Group specialised register of trials, hand-searching of atopic eczema conference proceedings, follow-up of references in retrieved articles, contact with leading researchers and requests to relevant pharmaceutical companies. INCLUSION/EXCLUSION CRITERIA: Only RCTs of therapeutic agents used in the prevention and treatment of people with atopic eczema of any age were considered for inclusion. Only studies where a physician diagnosed atopic eczema or atopic dermatitis were included. DATA EXTRACTION: Data extraction was conducted by two observers onto abstraction forms, with discrepancies resolved by discussion. QUALITY ASSESSMENT: The quality assessment of retrieved RCTs included an assessment of: a clear description of method and concealment of allocation of randomisation, the degree to which assessors and participants were blinded to the study interventions, and whether all those originally randomised were included in the final main analysis. DATA SYNTHESIS: Where possible, quantitative pooling of similar RCTs was conducted using the Cochrane Collaboration's methods. Where statistical heterogeneity was found, sources of heterogeneity in terms of study participants, formulation or posology of intervention, and use of co-treatments were explored. Where pooling was not deemed to be appropriate, detailed descriptions of the study characteristics and main reported results were presented along with comments on study quality. RESULTS: A total of 1165 possible RCTs were retrieved in hard copy form for further scrutiny. Of these, 893 were excluded from further analysis because of lack of appropriate data. The 272 remaining RCTs of atopic eczema covered at least 47 different interventions, which could be broadly categorised into ten main groups. Quality of reporting was generally poor, and limited statistical pooling was possible only for oral cyclosporin, and only then after considerable data transformation. There was reasonable RCT evidence to support the use of oral cyclosporin, topical corticosteroids, psychological approaches and ultraviolet light therapy. There was insufficient evidence to make recommendations on maternal allergen avoidance for disease prevention, oral antihistamines, Chinese herbs, dietary restriction in established atopic eczema, homeopathy, house dust mite reduction, massage therapy, hypnotherapy, evening primrose oil, emollients, topical coal tar and topical doxepin. (ABSTRACT TRUNCATED)


Asunto(s)
Dermatitis Atópica/prevención & control , Eccema/prevención & control , Administración Cutánea , Corticoesteroides/uso terapéutico , Antiinfecciosos/uso terapéutico , Ensayos Clínicos como Asunto , Terapias Complementarias , Desensibilización Inmunológica , Dieta , Medicamentos Herbarios Chinos/uso terapéutico , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación
20.
Arch Dermatol ; 136(12): 1536-43, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11115167

RESUMEN

OBJECTIVE: To examine the efficacy and tolerability of calcipotriene combined with phototherapy or systemic therapies compared with monotherapy for the treatment of chronic plaque psoriasis. DESIGN: Quantitative systematic review of 11 randomized controlled trials involving a total of 756 patients with plaque psoriasis. MAIN OUTCOME MEASURES: Rate ratios (RRs) for marked improvement or clearance in patient and investigator overall assessments of response; mean difference in percentage change in Psoriasis Area and Severity Index; and RRs for clearance in patient and investigator overall assessments of response. Adverse effects were estimated with the RR and the rate difference in terms of withdrawal rate, proportion of patients experiencing adverse events, and proportion of patients with cutaneous and noncutaneous adverse effects. RESULTS: Antipsoriatic effects of acitretin, cyclosporine, and psoralen-UV-A phototherapy were enhanced with the addition of topical calcipotriene using the Psoriasis Area and Severity Index as the outcome, but this is not translated into an increase in the number of patients who achieve at least marked improvement. At the end of treatment, the RRs for marked improvement or clearance in patient assessments were as follows: calcipotriene plus acitretin vs acitretin alone (12 weeks), 1.4 (95% confidence interval [CI], 1.0-1. 9); calcipotriene plus cyclosporine vs cyclosporine alone (6 weeks), 1.2 (95% CI, 0.9-1.6); and calcipotriene plus psoralen-UV-A vs psoralen-UV-A alone (12 weeks), 1.2 (95% CI, 0.9-1.6). Patients were also no more likely to obtain marked improvement or better with calcipotriene plus UV-B therapy than with UV-B therapy alone (RR, 1. 0; 95% CI, 0.8-1.1 at 8 weeks in the patient assessment). There is limited evidence that use of calcipotriene might reduce the cumulative exposure to phototherapy and systemic treatment. During the short duration of these trials, there were no significant differences in withdrawal rates or adverse effects between the combined regimens and their corresponding monotherapy control interventions. CONCLUSIONS: Overall, there is insufficient evidence to support any large effects in favor of combination treatment. In the patient assessments, the results do not show an adjuvant effect, but there is some evidence that use of calcipotriene might reduce cumulative exposure to systemic therapy to obtain clearance. There were no long-term morbidity data on the effectiveness of any of the combinations studied. Given that psoriasis is a chronic recurrent disease for most patients, longer trials are needed to determine whether the addition of topical calcipotriene to systemic therapy improves the risk-benefit ratio by reducing the long-term risk of toxic effects. Equally important is the need to examine the impact of such combinations on the duration of remission after treatment.


Asunto(s)
Calcitriol/análogos & derivados , Calcitriol/administración & dosificación , Fármacos Dermatológicos/administración & dosificación , Psoriasis/tratamiento farmacológico , Administración Cutánea , Enfermedad Crónica , Esquema de Medicación , Quimioterapia Combinada , Humanos , Fototerapia , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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