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1.
Pediatr Cardiol ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724761

RESUMO

Prediction of outcomes following a prenatal diagnosis of congenital heart disease (CHD) is challenging. Machine learning (ML) algorithms may be used to reduce clinical uncertainty and improve prognostic accuracy. We performed a pilot study to train ML algorithms to predict postnatal outcomes based on clinical data. Specific objectives were to predict (1) in utero or neonatal death, (2) high-acuity neonatal care and (3) favorable outcomes. We included all fetuses with cardiac disease at Sunnybrook Health Sciences Centre, Toronto, Canada, from 2012 to 2021. Prediction models were created using the XgBoost algorithm (tree-based) with fivefold cross-validation. Among 211 cases of fetal cardiac disease, 61 were excluded (39 terminations, 21 lost to follow-up, 1 isolated arrhythmia), leaving a cohort of 150 fetuses. Fifteen (10%) demised (10 neonates) and 65 (48%) of live births required high acuity neonatal care. Of those with clinical follow-up, 60/87 (69%) had a favorable outcome. Prediction models for fetal or neonatal death, high acuity neonatal care and favorable outcome had AUCs of 0.76, 0.84 and 0.73, respectively. The most important predictors for death were the presence of non-cardiac abnormalities combined with more severe CHD. High acuity of postnatal care was predicted by anti Ro antibody and more severe CHD. Favorable outcome was most predicted by no right heart disease combined with genetic abnormalities, and maternal medications. Prediction models using ML provide good discrimination of key prenatal and postnatal outcomes among fetuses with congenital heart disease.

3.
Ultrasound Obstet Gynecol ; 55(6): 806-814, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31332850

RESUMO

OBJECTIVES: To evaluate the utility of ultrasound markers in the management of pregnancies complicated by preterm prelabor rupture of membranes (PPROM) between 23 + 0 and 33 + 6 weeks' gestation, and to assess the ability of ultrasound markers to predict adverse neonatal outcomes. METHODS: This was a retrospective cohort study of all patients with PPROM between 23 + 0 and 33 + 6 weeks' gestation and latency period (PPROM to delivery) > 48 h, who delivered before 34 weeks' gestation at a tertiary referral center between 2005 and 2017. All patients underwent a non-stress test daily and an ultrasound scan twice a week for assessment of amniotic fluid volume, biophysical profile (BPP) and umbilical artery (UA) pulsatility index (PI). In patients with suspected fetal growth restriction, fetal middle cerebral artery (MCA)-PI was also assessed and the cerebroplacental ratio (CPR) calculated. The last ultrasound examination performed prior to delivery was analyzed. We compared the characteristics and outcomes between women who were delivered owing to clinical suspicion of chorioamnionitis and those who were not delivered for this indication. The primary objective was to evaluate the utility of ultrasound in the management of patients with PPROM. The secondary objective was to assess the diagnostic performance of ultrasound markers (BPP score < 6, oligohydramnios, UA-PI > 95th percentile, MCA-PI < 5th percentile, CPR < 5th percentile) for the prediction of composite adverse neonatal outcome, which was defined as the presence of one or more of: perinatal death, respiratory distress syndrome, periventricular leukomalacia, intraventricular hemorrhage Grade 3 or 4, necrotizing enterocolitis, hypoxic ischemic encephalopathy, neonatal sepsis or neonatal seizures. RESULTS: A total of 504 women were included in the study, comprising 120 with suspected chorioamnionitis and 384 without. Women with suspected chorioamnionitis, compared with those without, were less likely to be nulliparous (34.2% vs 45.3%; P = 0.03) and more likely to have fever (50.8% vs 2.6%; P < 0.001) and be delivered by Cesarean section (69.2% vs 42.4%; P < 0.001), mainly owing to a history of previous Cesarean section (18.3% vs 9.1%; P = 0.005) and to having non-reassuring fetal heart rate tracings (32.5% vs 14.6%; P < 0.001). No significant differences were found between the two groups with regard to the median amniotic fluid volume, overall BPP score, BPP score < 6, MCA-PI or CPR. Median UA-PI was slightly higher in the suspected-chorioamnionitis group, yet the incidence of UA-PI > 95th percentile was similar between the two groups. There was a higher incidence of composite adverse neonatal outcome in the group with suspected chorioamnionitis than in the group without (78.3% vs 64.3%, respectively; P = 0.004). However, on logistic regression analysis, none of the ultrasound markers evaluated was found to be associated with chorioamnionitis or composite adverse neonatal outcome, and they all had a poor diagnostic performance for the prediction of chorioamnionitis and composite adverse neonatal outcome. CONCLUSIONS: Commonly used ultrasound markers in pregnancies complicated by PPROM were similar between women delivered for suspected chorioamnionitis and those delivered for other indications, and performed poorly in predicting composite adverse neonatal outcome. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Ruptura Prematura de Membranas Fetais/diagnóstico por imagem , Ultrassonografia Pré-Natal/estatística & dados numéricos , Adulto , Líquido Amniótico , Biomarcadores/análise , Cesárea/estatística & dados numéricos , Corioamnionite/diagnóstico por imagem , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Humanos , Recém-Nascido , Oligo-Hidrâmnio/diagnóstico por imagem , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Terceiro Trimestre da Gravidez , Fluxo Pulsátil , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/embriologia
4.
Br J Pharmacol ; 168(4): 863-79, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22994368

RESUMO

BACKGROUND AND PURPOSE: Nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor antagonists have been proposed as a novel therapeutic approach to Parkinson's disease. Main limitations of previous studies were the use of structurally similar compounds and the evaluation of their acute effects only. We report here on the acute and long-term antiparkinsonian effects of the novel compound 2-[3-[4-(2-chloro-6-fluoro-phenyl)-piperidin-1-ylmethyl]-2-(morpholine-4-carbonyl)-indol-1-yl]-acetamide (NiK-21273) in comparison with the potent and selective NOP receptor antagonist SB-612111. EXPERIMENTAL APPROACH: Basic pharmacological properties of NiK-21273 were studied in cell lines and isolated tissues (mouse and rat vas deferens). Antiparkinsonian effects were studied in reserpinized mice and 6-hydroxydopamine hemilesioned rats under both acute and chronic administration protocols. KEY RESULTS: In vitro, NiK-21273 behaved as a potent (pA(2) 7.7) and selective NOP receptor antagonist. In vivo, it reduced hypokinesia in reserpinized mice at 0.1 and 1 but not 10 mg·kg(-1), whereas SB-612111 (0.01-1 mg·kg(-1)) provided a dose-dependent antiparkinsonian effect. NiK-21273 ameliorated motor performance in 6-hydroxydopamine hemilesioned rats at 0.5 and 5 but not 15 mg·kg(-1). SB-612111 replicated these effects in the 0.01-1 mg·kg(-1) range without loss of efficacy. Both antagonists synergized with L-DOPA at subthreshold doses. Chronic administration of NiK-21273 provided delayed improvement in baseline activity at 0.5 and 1.5 mg·kg(-1), although tolerance to the higher dose was observed. Conversely, SB-612111 (1 mg·kg(-1)) maintained its effects over time without modifying baseline activity. CONCLUSIONS AND IMPLICATIONS: NOP receptor antagonists provide motor benefit in parkinsonism models although the 'therapeutic' window and long-term effects may vary between compounds.


Assuntos
Antiparkinsonianos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Cicloeptanos/uso terapêutico , Indóis/uso terapêutico , Antagonistas de Entorpecentes , Transtornos Parkinsonianos/prevenção & controle , Piperidinas/uso terapêutico , Animais , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/farmacologia , Células CHO , Cálcio/metabolismo , Cricetinae , Cricetulus , Cicloeptanos/administração & dosagem , Cicloeptanos/farmacologia , Relação Dose-Resposta a Droga , Indóis/administração & dosagem , Indóis/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos , Atividade Motora/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/fisiopatologia , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides/genética , Reserpina/farmacologia , Teste de Desempenho do Rota-Rod , Transfecção , Ducto Deferente/efeitos dos fármacos , Receptor de Nociceptina
5.
Gynecol Oncol ; 128(2): 233-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23200911

RESUMO

OBJECTIVE: The quality of first surgery is one of the most important prognostic factors in ovarian cancer patients. Pre-surgical distinction of benign and malignant pelvic mass plays a critical role in ovarian cancer management and survival. The aim of this study was to evaluate the clinical performance of ROMA algorithm and of CA125 and HE4 in the triage of patients with a pelvic mass undergoing surgery, in order to discriminate benign from malignant disease. METHODS: Three hundred and forty-nine pre- and post-menopausal women, aged 18 years or older undergoing surgery because of a pelvic mass were enrolled: serum concentrations of CA125 and HE4 were determined and ROMA was calculated for each sample. RESULTS: Median serum CA125 and HE4 levels were higher in patients with EOC compared to subjects with benign disease (p<0.0001). The resultant accuracy (using Receiver Operating Characteristics, ROC Area) values for HE4, CA125 and ROMA showed a good performance ranging from 89.8% for CA125 in pre-menopausal patients to 93.3% for ROMA in post-menopausal patients: AUC for ROMA resulted significantly higher in comparison to CA125 alone (93.3% vs 90.3%, p=0.0018) in post menopausal patients. A sub-analysis considering the 40 patients with endometrioid disease showed the highest accuracy of HE4 in these patients. CONCLUSIONS: Data presented confirm the accuracy of HE4 and of the ROMA algorithm in the distinction of ovarian carcinoma from benign disease, with a trend towards better performance for ROMA than for CA125 alone, statistically significant in postmenopausal patients.


Assuntos
Algoritmos , Antígeno Ca-125/sangue , Proteínas de Membrana/sangue , Neoplasias Epiteliais e Glandulares/diagnóstico , Doenças Ovarianas/diagnóstico , Neoplasias Ovarianas/diagnóstico , Proteínas/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma Epitelial do Ovário , Técnicas de Apoio para a Decisão , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/sangue , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/cirurgia , Doenças Ovarianas/sangue , Doenças Ovarianas/patologia , Doenças Ovarianas/cirurgia , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Pelve/patologia , Pelve/cirurgia , Pós-Menopausa/sangue , Estudos Prospectivos , Curva ROC , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos , Adulto Jovem
6.
J Endocrinol Invest ; 36(2): 92-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22398397

RESUMO

Glucocorticoid-induced osteoporosis (GIO) is the most frequent cause of secondary osteoporosis. GIO is linked to glucocorticoids (GC) daily assumption with maximum effect within first months of treatment and decreasing to basal levels as the therapy is discontinued. In Italy, primary prevention of GIO is suggested when GC therapy (prednisone >5 mg/day or equivalent) is taken for longer than 3 months. Lazio GISMO (Italian Group for Study and Diagnosis of Bone Metabolism Diseases) group organized the GC and Osteoporosis Epidemiology study (EGEO) to evaluate physician's approach in preventing GIO. The study involved 19 osteoporosis centers. Patients taking long-term GC therapy were recruited and information collected: medical history and anthropometric data, GC therapy, primary disease, physician's specialty, osteopororosis screening, and pharmacological intervention. The study included 1334 patients. Mean age was 63 ± 13 yr; 243 (18%) patients had a history of falls from standing position in the previous 12 months, 78 (35%) vertebral fractures, 91 (41%) fractures other than vertebral, 27 (12%) femoral fractures, and 27 (12%) multiple sites fractures. The molecules of GC more often prescribed were prednisone and 6-metil prednisolone. One thousand and forty patients (78%) were taking GC for more than 6 months. GC therapy was prescribed more frequently by rheumatologists (62%). Antiosteoporotic drugs for GIO prevention were prescribed in 431 patients (32%). Among the patients, only 27% (360) received calcium and vitamin D supplements, and 39% (319) treated by rheumatologists received anti-resorptive drugs. In conclusion, our data show that in Italy, as already described elsewhere, only a small subpopulation of GC-treated patients was supported by an anti-osteoporotic therapy, indicating the need to further stimulate awareness of both patients and specialists, prescribing GC therapy, to an appropriate and prompt GIO prevention.


Assuntos
Glucocorticoides/efeitos adversos , Osteoporose/induzido quimicamente , Osteoporose/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Estudos de Coortes , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Estudos Prospectivos , Adulto Jovem
7.
Leukemia ; 25(5): 814-20, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21331069

RESUMO

In acute promyelocytic leukemia (APL) the retinoic acid receptor alpha (RARα) becomes an oncogene through the fusion with several partners, mostly with promyelocytic leukemia protein (PML), all of which have in common the presence of a self-association domain. The new fusion proteins, therefore, differently from the wild-type RARα, which forms only heterodimers with retinoic X receptor alpha, are also able to homo-oligomerize. The presence of such a domain has been suggested to be crucial for the leukemogenic potential of the chimeric proteins found in APL blasts. Whether or not any self-association domain is sufficient to bestow a leukemogenic activity on RARα is still under investigation. In this work, we address this question using two different X-RARα chimeras, where X represents the coiled-coil domain of PML (CC-RARα) or the oligomerization portion of the yeast transcription factor GCN4 (GCN4-RARα). We demonstrate that in vitro both proteins have transforming potential, and recapitulate the main PML-RARα biological properties, but CC-RARα is uniquely able to disrupt PML nuclear bodies. Indeed, in vivo only the CC-RARα chimera induces efficiently APL in a murine transplantation model. Thus, the PML CC domain represents the minimal structural determinant indispensable to transform RARα into an oncogenic protein.


Assuntos
Transformação Celular Neoplásica , Leucemia Promielocítica Aguda/genética , Proteínas Nucleares/genética , Receptores do Ácido Retinoico/genética , Proteínas Recombinantes de Fusão/fisiologia , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Animais , Western Blotting , Cromatografia em Gel , Imunofluorescência , Células-Tronco Hematopoéticas/metabolismo , Imunofenotipagem , Imunoprecipitação , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Camundongos , Proteína da Leucemia Promielocítica , Multimerização Proteica , RNA Mensageiro/genética , Receptor alfa de Ácido Retinoico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Arch Gerontol Geriatr ; 49 Suppl 1: 231-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19836638

RESUMO

Syncope is a common disorder that can lead to serious consequences in the elderly. Tilt-test is a safe, useful specific tool to investigate recurrent syncope also in the elderly. Comorbidities and medication use, widely present in elderly patients, affecting the hemodynamic response, can influence the tilt-test outcome. The aim of this study was to evaluate the influence of these confounding factors on tilt-test results in elderly patients with recurrent syncope. We included in this study a consecutive group of 87 patients>75 years (82.1+/-4.3 years) with unexplained syncope. They underwent passive upright tilt-test. Heart rate an blood pressure were recorded using non-invasive devices. The patients were classified according to the modified Vasovagal Syncope International Study (VASIS). Comorbidities were measured with the geriatric index of comorbidities (GIC), which is a composite score taking into account both the number of diseases and their severity as measured by Greenfield's IDS. The tilt-test was positive in 22 patients. There were no significant differences in clinical characteristics, and medication use between the tilt-test negative and positive patients, except for the GIC score (1.12+/-0.5 vs. 2.42+/-0.48; p=0.001) and for a reduced number of medications in the former group (5.7+/-3.1 vs. 8.2+/-2.4; p=0.001). This study suggests that comorbidities and the number of medications could influence tilt test outcome.


Assuntos
Envelhecimento/fisiologia , Comorbidade/tendências , Síncope/epidemiologia , Síncope/fisiopatologia , Teste da Mesa Inclinada/métodos , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia Ambulatorial , Feminino , Humanos , Incidência , Masculino , Prognóstico , Recidiva , Fatores de Risco , Síncope/diagnóstico
9.
Arch Gerontol Geriatr Suppl ; (9): 121-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15207406

RESUMO

Today home health care (HHC) programs have been developed in numerous Western countries, in order to answer the questions regarding the care of frail elderly suffering from polypathologies and, therefore, being at high risk of disability. The HHC program of the Israelite Hospital of Rome has been planned as a complementary model, and not as a substitute of hospitalization, being able to offer flexible services, suitable for each elderly patient. The present study has established that taking care of old patients in their home allows us to prevent the deterioration of cognitive performance and functional impairments,as measured by the mini mental state examination (MMSE), the scales of activity of daily living (ADL), and the instrumental activity of daily living (IADL), respectively. We found considerable improvements also in the mood disorders during HHC, as measured by the geriatric depression scale (GDS). All psychometric tests were administered at the beginning of home care and after almost 1 year. Moreover, we formulated some questions regarding the quality of the offered services, and the answers revealed great satisfaction of both the patients and their caregivers.


Assuntos
Transtornos Cognitivos/prevenção & controle , Idoso Fragilizado , Nível de Saúde , Serviços de Assistência Domiciliar , Serviços Preventivos de Saúde/organização & administração , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/diagnóstico , Depressão/diagnóstico , Depressão/psicologia , Avaliação da Deficiência , Feminino , Serviços de Assistência Domiciliar/normas , Humanos , Masculino , Transtornos do Humor/diagnóstico , Transtornos do Humor/psicologia , Testes Neuropsicológicos , Inquéritos e Questionários
10.
J Clin Endocrinol Metab ; 86(11): 5427-32, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11701717

RESUMO

L-[1-13C]Leucine, [1-13C]glycine, L-[1-13C]phenylalanine, and L-[1-13C]proline were infused as a bolus into the maternal circulation of seven appropriate for gestational age at 30.3 +/- 3.0 wk and 7 intrauterine growth-restricted pregnancies at 26.5 +/- 1.0 wk gestation to investigate placental transport in vivo. Umbilical venous samples were obtained at the time of in utero fetal blood sampling at 450 +/- 74 sec from the bolus injection. In normal pregnancies the fetal/maternal (F/M) enrichment ratios for leucine (0.76 +/- 0.06) and phenylalanine (0.77 +/- 0.06) were higher (P < 0.01) than the F/M ratios for glycine (0.18 +/- 0.04) and proline (0.22 +/- 0.02). This suggests that these two essential amino acids rapidly cross the placenta in vivo. Compared with the essentials, both glycine and proline had significantly lower F/M enrichment ratios, which were not different from each other. The results support the hypothesis that amino acids with high affinity for exchange transporters cross the placenta most rapidly. In intrauterine growth-restricted pregnancies, the F/M enrichment ratio was significantly lower (P < 0.01) for L-[1-13C]leucine (0.76 +/- 0.06 vs. 0.48 +/- 0.07) and for L-[1-13C]phenylalanine (0.77 +/- 0.06 vs. 0.46 +/- 0.07) compared with appropriate for gestational age pregnancies reflecting impaired transplacental flux. The F/M enrichment ratio did not differ for [1-13C]glycine (0.18 +/- 0.04 vs. 0.17 +/- 0.03), and L-[1-13C]proline (0.22 +/- 0.02 vs. 0.18 +/- 0.04).


Assuntos
Aminoácidos/metabolismo , Retardo do Crescimento Fetal/metabolismo , Placenta/metabolismo , Adulto , Animais , Transporte Biológico Ativo , Feminino , Feto/metabolismo , Glicina/metabolismo , Humanos , Leucina/metabolismo , Fenilalanina/metabolismo , Gravidez , Prolina/metabolismo , Ovinos
13.
Bioorg Med Chem ; 9(7): 1871-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11425589

RESUMO

An efficient approach to 1-[(3R,4R)-1-cyclooctylmethyl-3-hydroxymethyl-4-piperidyl]-3-ethyl-1,3-dihydro-benzimidazol-2-one (J-113397) 1, the first non-peptide ORL-1 receptor antagonist described in literature, is outlined. After construction of the piperidine framework through Dieckmann cyclization of the Michael adduct 8 of cyclooctylmethylamine to methyl acrylate, condensation with o-phenylendiamine produced the beta-enamino ester 2, which has been conveniently used to construct the benzimidazolone substituent at C-4. Catalytic hydrogenation of intermediate 11 followed by base-promoted cis--trans isomerization of the key compound 12 led to the formation of ester 13, which was converted to the racemic title compound by LiAlH(4) reduction. The pure enantiomers were obtained by chiral preparative HPLC separation using a derivatized cellulose-based stationary phase.


Assuntos
Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Antagonistas de Entorpecentes/síntese química , Antagonistas de Entorpecentes/farmacologia , Piperidinas/síntese química , Piperidinas/farmacologia , Cromatografia Líquida de Alta Pressão , Receptores Opioides , Análise Espectral , Receptor de Nociceptina
14.
Farmaco ; 56(1-2): 117-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11347951

RESUMO

In the last decade a number of selective and potent non-peptidic agents became available to explore the usefulness of the delta-opioid receptor in modulation of pain of different origins. As a continuing effort in this field, potent and selective delta-opioid agonists based on the pyrrolomorphinan framework have been designed, synthesised and characterised biologically in our laboratories. In animal models, a selected compound of interest, SB 235863, has proved the concept that selective delta-opioid agonists may have great potential as pain relief agents in inflammatory and neuropathic pain conditions. Importantly, such a compound was free of the unwanted side effects usually associated with narcotic analgesics such as morphine.


Assuntos
Analgésicos Opioides/farmacologia , Receptores Opioides delta/agonistas , Animais , Desenho de Fármacos , Humanos , Inflamação/tratamento farmacológico , Dor/tratamento farmacológico , Relação Estrutura-Atividade
15.
Eur J Cancer ; 37(1): 97-105, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11165136

RESUMO

The mode of action of Ecteinascidin-743 (ET-743), a marine tetrahydroisoquinoline alkaloid isolated from Ecteinascidia turbinata, which has shown very potent antitumour activity in preclinical systems and encouraging results in Phase I clinical trials was investigated at a cellular level. Both SW620 and LoVo human intestinal carcinoma cell lines exposed for 1 h to ET-743 progress through S phase more slowly than control cells and then accumulate in the G2M phase. The sensitivity to ET-743 of G1 synchronised cells was much higher than that of cells synchronised in S phase and even higher than that of cells synchronised in G2M. ET-743 concentrations up to four times higher than the IC(50) value caused no detectable DNA breaks or DNA-protein cross-links as assessed by alkaline elution techniques. ET-743 induced a significant increase in p53 levels in cell lines expressing wild-type (wt) (p53). However, the p53 status does not appear to be related to the ET-743 cytotoxic activity as demonstrated by comparing the drug sensitivity in p53 (-/-) or (+/+) mouse embryo fibroblasts and in A2780 ovarian cancer cells or the A2780/CX3 sub-line transfected with a dominant-negative mutant TP53. The cytotoxic potency of ET-743 was comparatively evaluated in CHO cell lines proficient or deficient in nucleotide excision repair (NER), and it was found that ET-743 was approximately 7-8 times less active in ERCC3/XPB and ERCC1-deficient cells than control cells. The findings that G1 phase cells are hypersensitive and that NER-deficient cells are resistant to ET-743 indicate that the mode of action of ET-743 is unique and different from that of other DNA-interacting drugs.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Dioxóis/uso terapêutico , Isoquinolinas/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Ciclo Celular/efeitos dos fármacos , Divisão Celular , Neoplasias do Colo/patologia , Ciclinas/metabolismo , Dano ao DNA , DNA de Neoplasias/análise , Dioxóis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Isoquinolinas/farmacologia , Tetra-Hidroisoquinolinas , Trabectedina , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
16.
Brain Res Mol Brain Res ; 80(2): 166-76, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11038249

RESUMO

Several non-peptidic opioids have been synthesized recently as part of a program to develop selective delta receptor agonists. In this study, the affinities of a set of compounds for cloned delta and mu opioid receptors expressed in HEK 293 cell lines were determined by competition analysis of [3H]bremazocine binding to membrane preparations. All compounds studied exhibited high affinity and selectivity, with apparent dissociation constants in the range of 0.6-1.7 nM for the delta opioid receptor and 240-1165 nM for the mu opioid receptor. We next sought to determine which domain of the delta receptor was critical for mediating the highly selective binding by analysis of ligand affinities for mu/delta receptor chimeras. Receptor binding profiles suggested that a critical site of receptor/ligand interaction was located between transmembrane domain 5 (TM5) and TM7 of the delta receptor. Substitution of tryptophan 284, located at the extracellular surface of TM6, with lysine, which is found at the equivalent position in the mu opioid receptor, led to a spectrum of effects on affinities, depending on the ligand tested. Affinities of SB 219825 and SB 222941 were particularly sensitive to the substitution, displaying a 50-fold and 70-fold decrease in affinity, respectively. Activities of the delta receptor-selective agonists were tested in two functional assays. Brief exposure of HEK 293 cells expressing delta opioid receptors with selective ligands induced phosphorylation of MAP kinase, although the non-peptidic ligands were less efficacious than the enkephalin derivative DADL (Tyr-D-Ala-Gly-Phe-D-Leu). Similarly, chronic exposure of HEK 293 cells expressing delta opioid receptors with selective, non-peptidic ligands, with the exception of SB 206848, caused receptor down-regulation, however, the SB compounds were less efficacious than DADL.


Assuntos
Receptores Opioides delta , Sequência de Aminoácidos , Analgésicos/metabolismo , Analgésicos/farmacologia , Analgésicos Opioides/metabolismo , Analgésicos Opioides/farmacologia , Benzomorfanos/metabolismo , Benzomorfanos/farmacologia , Ligação Competitiva , Células Cultivadas , Clonagem Molecular , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Leucina Encefalina-2-Alanina/farmacologia , Proteínas de Ligação ao GTP/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Indóis/química , Indóis/farmacologia , Isoquinolinas/química , Isoquinolinas/farmacologia , Rim/citologia , Ligantes , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Morfina/metabolismo , Morfina/farmacologia , Mutagênese Sítio-Dirigida , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Quinolinas/química , Quinolinas/metabolismo , Quinolinas/farmacologia , Ensaio Radioligante , Receptores Opioides delta/agonistas , Receptores Opioides delta/antagonistas & inibidores , Receptores Opioides delta/genética , Receptores Opioides mu/agonistas , Receptores Opioides mu/antagonistas & inibidores , Receptores Opioides mu/genética , Trítio
17.
Br J Cancer ; 82(10): 1732-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10817511

RESUMO

By exposing Igrov-1 human ovarian cancer cells to increasing concentrations of Ecteinascidin-743 (ET-743), either for a short or prolonged time, we obtained sublines resistant to ET-743 which overexpress Pgp. The most resistant clone (Igrov-1/25 ET) was evaluated for biological and pharmacological characterizations. The increased Pgp levels of Igrov-1/25 ET were not due to amplification of the mdr-1 gene but to increased mRNA levels. No increase in other multidrug resistance-related proteins such as MRP or LRP was observed in Igrov-1/25 ET. The IC50 values of ET-743 against Igrov-1/25 ET was approximately 50 times higher than the parental cell line. Resistance was not reversed while maintaining the cell line in drug-free medium for at least 24 months. Igrov-1/25 ET was cross-resistant to Doxorubicin and VP16 while it was equally sensitive to L-PAM, MNNG, CPT and only marginally less sensitive to Cis-DDP and Oxaliplatin compared to the parental cell line. Igrov-1/25 ET exposed to Doxorubicin retained this drug much less, mainly because of a more efficient drug efflux. The cyclosporine analogue SDZ PSC-833 reversed the resistance of Igrov-1/25 ET to ET-743, without any enhancement of the drug activity against the parental Igrov-1 cell line. Igrov-1/25 ET exhibits typical features of cell lines overexpressing the mdr-1 gene and can be a potentially useful tool in selecting ET-743 non-cross-resistant analogues as well as to investigate methods to counteract resistance to this drug.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Dioxóis/farmacologia , Isoquinolinas/farmacologia , Neoplasias Ovarianas , Células Tumorais Cultivadas/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/farmacocinética , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Citometria de Fluxo , Genes MDR , Humanos , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Tetra-Hidroisoquinolinas , Trabectedina , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia , Partículas de Ribonucleoproteínas em Forma de Abóbada/metabolismo
18.
Clin Nutr ; 18(5): 259-67, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10601532

RESUMO

Malnutrition is a frequent condition, both widely represented in geriatric population and underestimated in diagnostic and therapeutic work-up, and is known to affect health status and life expectancy of elderly people. The unexpected weight loss is a pathological condition, recently classified in three different ways (sarcopenia, wasting and cachexia) according to criteria of nutritional intake, functional abilities and age-related body composition modifications, that is caused by social psychological and medical factors. In this review, the authors highlight the ways that, through malnutrition, could lead to an impairment of quality of life in elderly people. Notwithstanding the great impreciseness and confusion that surrounds the term 'quality of life', the authors focus their attention on the correlation existing with the recently occurring changes to patients' health status and life-style, analysing the relationship with frailty, failure to thrive and homeostatic balance failure syndrome. With the latter term, the authors introduce a pathological condition widely represented in the late stages of malnutrition that often evolves in multiple organ failure and lastly in the death.


Assuntos
Distúrbios Nutricionais , Qualidade de Vida , Idoso , Feminino , Idoso Fragilizado , Nível de Saúde , Humanos , Insuficiência de Múltiplos Órgãos/etiologia , Distúrbios Nutricionais/etiologia , Distúrbios Nutricionais/fisiopatologia , Distúrbios Nutricionais/psicologia , Redução de Peso/fisiologia
19.
Am J Obstet Gynecol ; 181(2): 477-83, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10454703

RESUMO

OBJECTIVE: Our purpose was to establish whether, in normal human pregnancies, the maternal intravenous infusion of amino acids can increase fetal amino acid uptake and amino acid concentrations. STUDY DESIGN: Twenty-six normal pregnancies were studied at the time of cesarean delivery (38-40 weeks' gestation). In 10 cases an amino acid formulation (Freamine 8.5% III, Baxter) was infused into a maternal vein before cesarean delivery. Maternal blood samples were obtained during the course of the study. Umbilical venous and arterial samples were obtained from the clamped segment of the cord. There were no differences between the 2 groups for fetal and placental weights and for fetal oxygenation and acid-base balance. RESULTS: Maternal amino acid concentrations increased significantly in the group receiving infusions. Significant increases in umbilical venous concentrations were observed for most amino acids, except for histidine and threonine. The amino acid umbilical arteriovenous differences per mole of oxygen (AA/O(2) ratio) increased significantly for leucine, isoleucine, valine, methionine, phenylalanine, arginine, glycine, serine, alanine, and proline. There were no significant increases for lysine, histidine, and threonine. CONCLUSION: An increase in maternal concentrations leads to an increase in the delivery of most amino acids to the fetus.


Assuntos
Aminoácidos/administração & dosagem , Aminoácidos/sangue , Troca Materno-Fetal , Artérias Umbilicais , Veias Umbilicais , Adulto , Artérias , Eletrólitos , Feminino , Glucose , Humanos , Soluções de Nutrição Parenteral , Gravidez , Soluções
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