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1.
ESMO Open ; 7(4): 100538, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35921761

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has severely affected cancer care and research by disrupting the prevention and treatment paths as well as the preclinical, clinical, and translational research ecosystem. In Italy, this has been particularly significant given the severity of the pandemic's impact and the intrinsic vulnerabilities of the national health system. However, whilst detrimental, disruption can also be constructive and may stimulate innovation and progress. The Italian Association of Medical Oncology (AIOM) has recognized the impact of COVID-19 on cancer care continuum and research and proposes the '2021 Matera statement' which aims at providing pragmatic guidance for policymakers and health care institutions to mitigate the impact of the global health crisis on Italian oncology and design the recovery plan for the post-pandemic scenario. The interventions are addressed both to the pillars (prevention, diagnosis, treatment, follow-up, health care professionals) and foundations of cancer care (communication and care relationship, system organization, resources, research, networking). The priorities to be implemented can be summarized in the MATERA acronym: Multidisciplinarity; Access to cancer care; Telemedicine and Territoriality; Equity, ethics, education; Research and resources; Alliance between stakeholders and patients.


Assuntos
COVID-19 , Oncologia , Ecossistema , Humanos , Neoplasias , Pandemias
2.
Ig Sanita Pubbl ; 76(6): 330-345, 2020.
Artigo em Italiano | MEDLINE | ID: mdl-33783432

RESUMO

The Covid-19 pandemic significantly increased the workload for the Italian Health Service. There is few information in the literature on the pediatric population and on the management of pediatric hospitals. The aim of this article is to describe the management of healthcare services during Covid-19 emergency in Regina Margherita Children's Hospital. The Regina Margherita Children's Hospital is specialized in the prevention, diagnosis and treatment of pediatric diseases. About 1000 health worker work in this Hospital and 278 hospitalization places are available.


Assuntos
COVID-19 , Serviço Hospitalar de Emergência , Pandemias , Criança , Hospitais Pediátricos , Humanos , Itália , SARS-CoV-2
4.
J Thromb Haemost ; 17(2): 345-349, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30552749

RESUMO

Essentials Low-molecular-weight heparin (LMWH) is used to prevent venous thromboembolism (VTE) in pregnancy. We evaluated the association between LMWH and large for gestational age (LGA) infants. We found no significant associations between LMWH use and LGA. LMWH does not appear to increase the risk for the delivery of an LGA infant. SUMMARY: Background Low-molecular-weight heparin (LMWH), an anticoagulant, is the recommended drug for thromboprophylaxis and treatment of venous thromboembolism (VTE) in pregnancy. During pregnancy, LMWH is routinely prescribed to mothers with an increased risk of VTE or with a history of thrombosis. Although clinical reports of larger offspring born to women administered LMWH have been noted, no studies to date have evaluated or associated the use of LMWH and large for gestational age (LGA) infants. Objectives To determine whether there is an association between LMWH usage in mothers and the prevalence of LGA. Patients/Methods We performed an analysis of the Ottawa and Kingston (OaK) Birth Cohort and report characteristics of LMWH and association LGA (> 10%ile). We used coarsened exact matching (CEM) methods to account for bias and confounding. Results A total of 7519 women from the OaK Birth Cohort were included; 59 were administered LMWH during pregnancy (0.78%). Mothers prescribed LMWH had significantly greater BMI (P = 0.0001), age (P = 0.0001) and parity (P = 0.02). Gestational length was shorter among women administered LMWH compared to those without treatment (37.7 ± 2.0 vs. 39.2 ± 2.0, P < 0.0001), an iatrogenic finding. The odds ratio of an LGA delivery among women administered LMWH was 1.02 (95% confidence interval [CI], 0.48-2.16; P = 0.96) in unadjusted analyses and was 1.15 (95% CI, 0.49-2.71) in the matched sample adjusted for maternal age, BMI and gestational age. Conclusions These results, although exploratory, provide indirect evidence of no increased risk of LGA infants among women prescribed LMWH.


Assuntos
Anticoagulantes/efeitos adversos , Macrossomia Fetal/induzido quimicamente , Heparina de Baixo Peso Molecular/efeitos adversos , Complicações Cardiovasculares na Gravidez/prevenção & controle , Tromboembolia Venosa/prevenção & controle , Adulto , Anticoagulantes/administração & dosagem , Feminino , Macrossomia Fetal/diagnóstico , Macrossomia Fetal/epidemiologia , Idade Gestacional , Heparina de Baixo Peso Molecular/administração & dosagem , Humanos , Ontário/epidemiologia , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/epidemiologia , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Adulto Jovem
5.
J Thromb Haemost ; 15(4): 685-694, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28106343

RESUMO

Essentials Clinical benefit of hospitalization vs. outpatient treatment in pulmonary embolism (PE) is unknown. We performed a propensity matched cohort study of hemodynamically stable PE patients. Regardless of the risk assessment, hospitalized patients had the highest rate of adverse event. If confirmed, ambulatory care of normotensive PE patients may be preferred whenever possible. SUMMARY: Background The decision to hospitalize or not patients with acute pulmonary embolism (PE) is controversial. Despite the advantages of close monitoring, hospitalization by itself may lead to in-hospital complications and potentially worsen the prognosis of PE patients. Objectives To determine the net clinical benefit of hospitalization vs. outpatient management of normotensive patients with acute pulmonary embolism (PE). Methods Retrospective cohort propensity score analysis (radius marching with replacement). Hemodynamically stable PE patients treated as outpatients or inpatients were matched to balance out differences for 28 patient characteristics and known risk factors for adverse events. The primary outcome was the rate of adverse events at 14 days, including recurrent venous thromboembolism, major bleeding or death. Results Among 1127 eligible patients, 1081 were included in the matched cohort, 576 treated as inpatients and 505 as outpatients. The 14-day rate of adverse events was 13.0% for inpatients and 3.3% for outpatients (adjusted OR, 5.07; 95% CI, 1.68-15.28). The 3-month rate was 21.7% for inpatients and 6.9% for outpatients (OR, 4.90; 95% CI, 2.62-9.17). In the high-risk subgroup (Pulmonary Embolism Severity Index class III-V; n = 597), the 14-day rate of adverse events was 16.5% for hospitalized patients vs. 4.5% for outpatients (OR, 4.16; 95% CI, 1.2-14.35). Conclusion Outpatient treatment of hemodynamically stable PE patients seems to be associated with a lower rate of adverse events than hospitalization and, if confirmed, may be considered as first-line management in patients not requiring specific in-hospital care, regardless of their initial risk stratification, if proper outpatient care can be provided.


Assuntos
Hospitalização , Pacientes Ambulatoriais , Embolia Pulmonar/terapia , Doença Aguda , Adulto , Idoso , Anticoagulantes/uso terapêutico , Feminino , Hemodinâmica , Hemorragia/induzido quimicamente , Humanos , Pacientes Internados , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Perfusão , Prognóstico , Pontuação de Propensão , Artéria Pulmonar/diagnóstico por imagem , Análise de Regressão , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Ultrassonografia , Tromboembolia Venosa/tratamento farmacológico
6.
Int J Tuberc Lung Dis ; 18(1): 122-4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24365564

RESUMO

We describe the relationship between socio-economic status and current bidi or cigarette smoking among Indian men aged ≥15 years. The prevalence of bidi smoking was 13.7% (95%CI 13.3-14.1) and that of cigarette smoking was 6.3% (95%CI 6.1-6.6). bidi smoking was concentrated among the socio-economically disadvantaged, while cigarette smoking was common among men with higher status occupations and greater levels of education and household wealth. This suggests that India has not transitioned to the later stages of the tobacco epidemic, and underscores the need for prevention and control strategies adapted to current patterns of consumption across socio-economic groups in India.


Assuntos
Fumar/economia , Fumar/epidemiologia , Fatores Socioeconômicos , Produtos do Tabaco/economia , Adolescente , Adulto , Idoso , Escolaridade , Inquéritos Epidemiológicos , Humanos , Renda , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Ocupações/economia , Prevalência , Classe Social , Adulto Jovem
7.
Ann Oncol ; 22(5): 1236-1242, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21078826

RESUMO

BACKGROUND: In advanced colorectal cancer, chemotherapy is usually administered without pauses and until progression but patients can experience cumulative toxicity and cannot tolerate a heavy therapeutic charge. AIM: The aim of the present trial was to evaluate whether an intermittent chemotherapy with levo-leucovorin + 5-fluorouracil (5-FU) + irinotecan (CPT-11) was at least as effective as the same regimen given continuously, both administered until progression, in patients affected with advanced colorectal cancer and not previously exposed to chemotherapy for metastatic disease. PATIENTS, MATERIALS AND METHODS: A total of 337 patients from 27 institutions were randomised between levo-leucovorin, 100/mg/m(2) i.v. + 5-FU; 400 mg/m(2) i.v. bolus + 5-FU; 600 mg/m(2) 22-h continuous infusion, days 1 and 2 + CPT-11; 180 mg/m(2) day 1, administered every 2 weeks 2 months on and 2 months off (arm A) and the same regimen administered continuously (arm B), until progression in both arms. The main end point was overall survival (OS), the secondary progression-free survival (PFS) and toxicity. RESULTS: At a median follow-up of 41 months, OS was 18 months in arm A and 17 months in arm B [hazard ratio (HR), 0.88]. Also PFS was comparable in the two groups (6 months in both, with HR, 1.03), and even grades 3-4 toxicity (mainly myelosuppression, fever and diarrhoea) was similar. Second-line oxaliplatin-based treatment was administered in a similar percentage (66%) in the two arms. The median chemotherapy-free period (drug holiday) in arm A was 3.5 months. CONCLUSION: Reducing the charge of therapy in this population did not diminish the efficacy of treatment. Further studies with this strategy, including biologicals, are warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Irinotecano , Estimativa de Kaplan-Meier , Levoleucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
Oncology ; 70(5): 366-77, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17179731

RESUMO

OBJECTIVE: The combined assessment of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and thymidine phosphorylase (TP) gene expressions in metastatic colorectal cancer has been reported to be able to predict the efficacy of fluoropyrimidine-based chemotherapy. In order to evaluate the prognostic role in the adjuvant setting, we investigated the TS, DPD and TP expression in primary tumors of colorectal cancer patients treated with 5-fluorouracil (5-FU). METHODS: TS, DPD and TP expression levels were determined by immunohistochemistry in paraffin-embedded primary tumor tissues from 62 patients with Dukes' stage B and C colorectal cancers who underwent surgery and received adjuvant systemic chemotherapy with 5-FU. The median follow-up was 90 months (range 17-127). RESULTS: Dukes' stage C cancer and high TS expression were independent markers of poor prognosis for disease-free survival (DFS; p = 0.0009 and p = 0.007, respectively) and overall survival (OS; p = 0.0005 and p = 0.011, respectively). By multivariate analysis, patients with high DPD expression had significantly shorter DFS (p = 0.007) and OS (p = 0.005) compared to patients with low DPD expression. In the combined analysis of 2 markers, patients with low TS and low DPD had the best outcome in terms of DFS (p = 0.007) and OS (p = 0.03). The analysis of all 3 proteins showed that the patients with low expression of all 3 markers had significantly longer DFS (p = 0.04) and OS (p = 0.01) than patients with a high value of any one of the protein expressions. However, the joint analysis of 3 markers (group with TS-/DPD-/TP-) could not identify a subgroup of patients with a better prognosis compared to the analysis of 2 markers (group with TS-/DPD-). The analysis of Dukes' stage C cancer patients confirmed a significant benefit in terms of DFS and OS (p = 0.001 and p = 0.006, respectively) when all 3 markers had low expression. We also found a positive significant correlation between TS and TP protein expression (p = 0.033). CONCLUSIONS: This retrospective investigation suggests that the combined assessment of TS and DPD may be useful to evaluate the prognosis of patients with Dukes' B and C colon carcinoma receiving 5-FU adjuvant chemotherapy. The role of TP as a predictor for 5-FU-based therapy needs further investigations.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/enzimologia , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Fluoruracila/uso terapêutico , Timidina Fosforilase/metabolismo , Timidilato Sintase/metabolismo , Idoso , Quimioterapia Adjuvante , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Intervalo Livre de Doença , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Tempo
9.
Oncology ; 64(2): 139-45, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12566911

RESUMO

OBJECTIVE: In this phase I-II study we explored the potential of the combination of weekly gemcitabine (GEM) and 24-hour continuous infusion of 5-fluorouracil (5-FU) in order to determine the toxicity profile in pancreatic cancer. The efficacy of this drug combination was studied as a secondary endpoint. METHODS: Twenty-one patients with histologically or cytologically proven unresectable or metastatic previously untreated pancreatic adenocarcinoma were included in this study. Two dose levels of GEM and two dose levels of 5-FU were evaluated in three cohorts of patients who received GEM 1,000 mg/m(2) and 5-FU 2,000 mg/m(2), GEM 1,200 mg/m(2) and 5-FU 2,000 mg/m(2), or GEM 1,200 mg/m(2) and 5-FU 2,250 mg/m(2), on days 1, 8, and 15, every 4 weeks, respectively. RESULTS: Grade 3-4 neutropenia was observed in 10% of the cycles. Non-myelosuppressive toxicities included fatigue (22%), grade 1-2 diarrhea (12%) and grade 1 liver toxicity. There was no limiting toxicity and the maximum tolerated dose has not been reached. Two patients experienced a partial response (9.5 +/- 12.6%) and 12 patients had stable disease (57.1 +/- 21.2%). Seven of the 14 symptomatic patients improved their disease-related symptoms and 4 of the 8 patients evaluable for clinical benefit had a clinically beneficial response (50 +/- 34.6%). The median progression-free survival was 6 months (range 2-28), median survival was 11 months (range 3-32+), and the actuarial 1-year survival rate 33%. CONCLUSION: The weekly administration of GEM combined with 24-hour continuous infusion of 5-FU shows a good safety profile at the dose levels evaluated. Some partial responses had also been achieved, disregarding the dose level of the two drugs. Survival confirms the activity of this drug combination.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/administração & dosagem , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sobrevida , Resultado do Tratamento , Gencitabina
10.
Eur J Cancer ; 38(4): 527-34, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11872345

RESUMO

Recent investigations have focused on the prognostic value of thymidylate synthase (TS) assessment in metastases of colorectal carcinoma (CRC). In order to evaluate the prognostic impact of TS expression after resection of metastases of colorectal cancer followed by systemic adjuvant chemotherapy, we performed an immunohistochemical characterisation of TS in the primary tumours and in the corresponding radically resected hepatic and pulmonary metastases. An additional objective was to compare the levels of TS in primary and metastatic disease. TS expression was assessed by immunohistochemistry using the monoclonal antibody TS 106. The study population consisted of 60 patients: 48 underwent liver and 12 lung resection. All of them received adjuvant chemotherapy after metastasectomy according to the Mayo Clinic schedule. In the 49 evaluable primary tumours, TS score was high in 53% and low in 47% of patients, while in the 60 metastatic samples TS immunostaining was high in 33% and low in 67%. There was a significantly smaller number of high TS expressors in metastatic than in primary tumours (P<0.04). No correlation was observed between TS expression and the site of the metastasis. TS status did not significantly correlate with the median disease-free interval (DFI) after metastasectomy, although this parameter was longer for patients with low TS immunoreactivity in the resected metastases than for those with high TS lesions (19.6 versus 13.8 months). Patients with high TS levels, however, had a significantly shorter median overall survival (OS) (27.6 months) than those with low TS expression (36.3 months) (P<0.008). TS status in the resected metastases confirmed its independent prognostic value in the multivariate analysis and was the only prognostic marker of OS in the subgroup of patients with resected liver metastases. These results suggest that high TS levels in resected metastases of colorectal cancer are associated with a poor outcome after surgery and 5-FU adjuvant therapy; therefore, a prospective assessment of TS levels in resected colorectal metastases could be useful to define which patients will most likely benefit from 5-FU adjuvant therapy after metastasectomy. Chemotherapeutic agents that target TS may not be the appropriate adjuvant treatment after metastasectomy for patients with a high TS expression in the resected metastases of colorectal cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/enzimologia , Neoplasias Hepáticas/enzimologia , Neoplasias Pulmonares/enzimologia , Timidilato Sintase/metabolismo , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Neoplasias Colorretais/tratamento farmacológico , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Imuno-Histoquímica , Leucovorina/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Prognóstico
11.
Hypertension ; 38(5): 1177-80, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11711518

RESUMO

Hypertension, diabetes, and hypercholesterolemia are characterized by a reduction in arterial distensibility and by accelerated atherosclerosis. Whether arterial stiffening is an inherent feature of these conditions or just the consequence of the atherosclerotic clinical or subclinical lesions is not known, however. Our aim was to obtain information on this issue by directly measuring, in humans, arterial distensibility both at the site of an atherosclerotic lesion and at the proximal normal site. In 10 patients (8 men; mean+/-SEM age, 65.2+/-3.4 years) affected by monolateral hemodynamic significant internal carotid artery stenosis, we measured arterial distensibility (Wall Track System; PIE Medical) bilaterally, both at the internal carotid artery and at the common carotid artery level. In the common carotid artery, measurements were made 3 cm below the bifurcation. In the affected internal carotid artery, measurements were made at the plaque shoulder (wall thickness of 2 mm). Measurements were made in the contralateral internal carotid artery at a symmetrical level. Arterial wall thickness was measured in the same site of arterial distensibility. Arterial distensibility was less in the internal than in the common carotid artery, with a marked reduction at the plaque internal carotid artery level compared with the corresponding contralateral site (-45%, P<0.01). It was also less, however, in the common carotid artery branching into the atherosclerotic internal carotid artery than in the contralateral common carotid artery (-25%, P<0.05). Wall thickness was similar in the 2 common carotid arteries and obviously greater in the affected internal carotid artery than in the contralateral artery. Arterial distensibility was markedly less in the internal carotid artery where there was a plaque compared with the intact contralateral internal carotid artery; it was also less, however, in the common carotid artery of the affected side in comparison with the contralateral common carotid artery. This provides evidence that the effect of a plaque on arterial mechanical properties is not limited to the actual plaque site but rather extends to a considerable degree in a proximal direction.


Assuntos
Artérias/fisiopatologia , Arteriosclerose/fisiopatologia , Idoso , Artérias/patologia , Arteriosclerose/patologia , Artérias Carótidas/patologia , Artérias Carótidas/fisiopatologia , Complacência (Medida de Distensibilidade) , Feminino , Humanos , Masculino
12.
Blood Cells Mol Dis ; 27(3): 559-71, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11355895

RESUMO

Recombinant human erythropoietin (rEpo) is being used with increasing frequency by endurance athletes to improve aerobic potential. Although rEpo administration has been banned by the International Olympic Committee, no methods are available to unequivocally detect its abuse in sports. Prompted by these considerations, we evaluated the main hematological and biochemical modifications measured in the blood of 18 volunteers upon rEpo administration. Different rEpo regimens, iron, folic acid, and vitamin B12 administration did not significantly modify the percentage increase in hematocrit. However, a significant decrease in circulating ferritin (fr) and an increase in the soluble transferrin receptor (sTfr) were not found in athletes receiving low (30 IU/kg) doses of rEpo. Thus, an increase in the sTfr/fr ratio cannot be used as an indicator of rEpo abuse, at least when the hormone is administered at low concentrations. In contrast, the amounts of beta-globin mRNA detected by quantitative competitive (RT)-PCR in whole blood samples significantly increased above the threshold levels in all of the treatments investigated. Taken together, these data suggest that hematocrit value, reticulocyte count, soluble transferrin receptor content, and concentration of beta-globin mRNA, when included in a new multiparametric formula, can detect rEpo abuse in 57.5% of the samples examined with a confidence interval of 99.99%. Thus, the method reported in this paper could significantly improve the tests currently available, which in similar experiments allowed the detection of rEpo abuse in only 7.6% of the samples examined.


Assuntos
Dopagem Esportivo/prevenção & controle , Eritropoetina , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Biomarcadores/sangue , Intervalos de Confiança , Eritropoetina/administração & dosagem , Eritropoetina/análise , Eritropoetina/farmacologia , Ferritinas/sangue , Ferritinas/efeitos dos fármacos , Globinas/genética , Hematócrito , Humanos , Masculino , Modelos Teóricos , RNA Mensageiro/sangue , RNA Mensageiro/efeitos dos fármacos , Receptores da Transferrina/sangue , Receptores da Transferrina/efeitos dos fármacos , Proteínas Recombinantes , Contagem de Reticulócitos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Detecção do Abuso de Substâncias/normas , Fatores de Tempo
13.
Chemistry ; 7(7): 1383-9, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11330890

RESUMO

We conducted relaxometric and water exchange studies of the cationic [Gd((S,S,S,S)-THP)(H2O)]3+ complex (THP 1,4,7,10-tetrakis(2-hydroxy-propyl)-1,4,7,10-tetraazacyclododecane). While the NMRD profiles obtained are typical for DOTA-like complexes (DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate), variable-temperature 7O NMR investigations revealed a relatively high water exchange rate (k(298)(ex) = 1.89 x 10(7) s(-1)). These results differ from those reported for other cationic tetraamide macrocyclic Gd(III) complexes, which exhibit characteristically low exchange rates. Since the low exchange rates are attributed partially to the geometry of the M isomer (square antiprismatic) in the tetraamide derivatives, the atypical water exchange rate observed in [Gd((S,S,S,S)-THP-(H2O)]3+ may result from a twisted square antiprismatic structure in this complex and from the relatively high steric strain at the water coordination site as a result of the presence of methyl groups at the alpha-position with respect to the Gd(III)-bound O atoms of THP.

14.
Chemistry ; 7(1): 64-71, 2001 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11205027

RESUMO

Magnetic resonance angiography (MRA) has put forth an impetus for the development of macromolecular GdIII complexes that have a prolonged lifetime in the vascular system. Herein, we report the synthesis and GdIII complexation of a new sugar conjugate based on inulin and the DO3A ligand (DO3A = 1,4,7,10-tetraazacyclododecan-1,4,7-triacetic acid). Two API-DO3ASQ conjugates (API = O-(aminopropyl)inulin, SQ = squaric acid = 3,4-dihydroxy-3-cyclobutene-1,2-dione) with different degrees of substitution (ds = 0.7 and ds = 1.5) were prepared from API by using the diethyl ester of squaric acid as a linking agent for the DO3A chelate. The efficacies of the resulting GdIII compounds were evaluated by investigation of their water 1H longitudinal-relaxation-rate enhancements at variable field (NMRD). A dramatic increase in relaxivity was observed in the more highly substituted conjugate (ds = 1.5); this prompted us to do a variable-temperature (17)O study in order to further characterize the relaxation parameters involved in this system. [Gd(API-DO3ASQ)] shows promising properties for application as a contrast agent for MRI.


Assuntos
Meios de Contraste/química , Gadolínio/química , Compostos Heterocíclicos com 1 Anel/química , Inulina/química , Angiografia por Ressonância Magnética , Compostos Organometálicos/química , Quelantes/química , Ciclobutanos/química , Compostos Heterocíclicos/química , Humanos , Espectroscopia de Ressonância Magnética , Isótopos de Oxigênio/química , Temperatura
16.
Inorg Chem ; 39(21): 4802-8, 2000 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-11196957

RESUMO

The formation of ion-pair adducts between the cationic complex La(THP)3+ (THP = 1,4,7,10-tetrakis(2-hydroxypropyl)-1,4,7,10-tetraazacyclododecane) and the anionic complexes Tm(DOTA)- (DOTA = 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetate), Tm(DTPA)2- (DTPA = diethylenetriamine-N,N,N',N",N"-pentaacetate), Tm(TTHA)3- (TTHA = triethylenetetraamine-N,N,N',N",N"',N"'-hexaacetate), and Tm(DOTP)5- (DOTP = 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetrakis(methylenephosphonate)) is examined by 13C NMR spectroscopy. The induced 13C shifts of the La(THP)3+ complex are followed by titration of the Tm(III) complexes of DOTA, DTPA, and TTHA at pH 7. From these data, the stability constants are calculated to be beta 1 = 64 M-1 (1:1), beta 1 = 296 M-1 (1:1), and beta 2 = 26,000 M-2 (2:1) for the ion pairs of La(THP)3+, with Tm(DOTA)-, Tm(DTPA)2-, and Tm(TTHA)3-, respectively. The La(THP)3+,Tm(DOTP)5- system elicits chiral resolution of the rapidly interconverting Tm(DOTP)5- isomers.

18.
AIDS ; 13(10): 1159-64, 1999 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-10416518

RESUMO

OBJECTIVE: To study the role of cell cycle regulation during HIV infection by investigating in vivo and in vitro cyclin B and p34 cdc kinase expression. METHODS: Cyclin B expression was analysed by Western blot in CD4 and CD8 cells from 25 HIV-infected patients and 24 uninfected individuals. In eight patients, a sequential analysis was performed after initiation of antiretroviral therapy (ART), and correlations with CD4 cell count and HIV viremia were studied. Sequential changes in cyclin B expression and p34 cdc kinase expression and activity were also studied in lymphocytes activated in vitro with phytohaemagglutinin (PHA). RESULTS: Lymphocytes from untreated HIV-infected patients demonstrate persistent in vivo overexpression of cyclin B in both CD4 and CD8 cell subpopulations. When cells are stimulated to proliferate in vitro, biochemical events that characterize the entrance into the cell cycle [ornithine decarboxylase (ODC) activity, interleukin 2 production, interleukin 2 alpha-chain receptor (IL-2R, CD25) expression, total protein synthesis, total DNA synthesis] show similar timing and sequence in lymphocytes from HIV-infected and uninfected individuals. However, in peripheral blood lymphocytes (PBL) from HIV-infected patients, cyclin B and p34 cdc kinase show premature expression during the cell cycle. Both in vivo cyclin B overexpression and in vitro unscheduled cyclin B expression were almost completely reversed 2-4 weeks after initiation of effective ART. CONCLUSION: Increased and unscheduled expression of cyclin B and p34 cdc kinase is consistently observed in CD4 and CD8 cells from HIV-infected patients, both in vivo and after in vitro mitogenic stimulation. These alterations correlate with the level of viremia and may provide a link between the perturbation of lymphocyte proliferative homeostasis and the exaggerated propensity towards apoptosis.


Assuntos
Proteína Quinase CDC2/metabolismo , Ciclina B/biossíntese , Infecções por HIV/imunologia , Linfócitos T/metabolismo , Apoptose , Western Blotting , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Ativação Enzimática , Infecções por HIV/virologia , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária , RNA Viral/sangue , Linfócitos T/imunologia , Linfócitos T/fisiologia
19.
Exp Cell Res ; 248(2): 381-90, 1999 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10222130

RESUMO

The movement of a cell through the sequential phases of apoptosis is accompanied by a progressive decrease in cell size with loss in protein mass. In lymphocytes from Hiv-infected persons, protein loss during apoptosis is due to increased protein degradation rather than decreased synthesis. To identify and characterize the proteolytic enzymes or enzyme systems involved in this process, we studied several features of protein turnover in lymphocytes from peripheral blood and lymph nodes during the natural and experimental infection by feline immunodeficiency virus (Fiv). This animal model allowed us to integrate in vivo results with in vitro observations of protein damage. Here we report that protein breakdown in apoptotic cells is concomitant with the activation of the ATP and ubiquitin-dependent multicatalytic system (proteasome). We suggest that proteasome activation is part of the proteolytic cascade in the execution phases of apoptosis in AIDS.


Assuntos
Cisteína Endopeptidases/metabolismo , Vírus da Imunodeficiência Felina/crescimento & desenvolvimento , Infecções por Lentivirus/metabolismo , Linfonodos/metabolismo , Linfócitos/metabolismo , Complexos Multienzimáticos/metabolismo , Ubiquitinas/metabolismo , Animais , Apoptose , Gatos , Feminino , Meia-Vida , Linfonodos/patologia , Linfócitos/patologia , Masculino , Complexo de Endopeptidases do Proteassoma , Proteínas/metabolismo
20.
Eur J Biochem ; 261(3): 775-83, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10215895

RESUMO

Mammalian red blood cell alpha-spectrin is ubiquitinated in vitro and in vivo [Corsi, D., Galluzzi, L., Crinelli, R., Magnani, M. (1995) J. Biol. Chem. 270, 8928-8935]. This process shows a cell age-dependent decrease, with senescent red blood cells having approximately one third of the amount of ubiquitinated alpha-spectrin found in young cells. In-vitro ubiquitination of alpha-spectrin was dependent on the source of the red cell membranes (those from older cells are less susceptible to ubiquitination than those from younger cells), on the source of ubiquitin-conjugating enzymes (those from older cells catalyze the process at a reduced rate compared to those from younger cells) and on the ubiquitin isopeptidase activity (which decreases during red cell ageing). However, once alpha-spectrin has been extracted from the membranes of young or old red blood cells, it is susceptible to ubiquitination to a similar extent regardless of source. This suggests that it is the membrane architecture, and not spectrin itself, that is responsible for the age-dependent decline in ubiquitination. Furthermore, spectrin oligomers, tetramers and dimers are also equally susceptible to ubiquitination. As spectrin ubiquitination occurs on domains alphaIII and alphaV of alpha-spectrin, and domain alphaV contains the nucleation site for the association of the alpha- and beta-spectrin chains, alterations in ubiquitination during red cell ageing could affect the stability and deformability of the erythrocyte membrane.


Assuntos
Senescência Celular , Membrana Eritrocítica/metabolismo , Espectrina/metabolismo , Ubiquitinas/metabolismo , Dimerização , Endopeptidases/sangue , Membrana Eritrocítica/enzimologia , Humanos
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