RESUMO
This work concerns the theoretical description of the quantum dynamics of molecular junctions with thermal fluctuations and probability losses. To this end, we propose a theory for describing non-Hermitian quantum systems embedded in constant-temperature environments. Along the lines discussed in [A. Sergi et al., Symmetry 10 518 (2018)], we adopt the operator-valued Wigner formulation of quantum mechanics (wherein the density matrix depends on the points of the Wigner phase space associated to the system) and derive a non-linear equation of motion. Moreover, we introduce a model for a non-Hermitian quantum single-molecule junction (nHQSMJ). In this model the leads are mapped to a tunneling two-level system, which is in turn coupled to a harmonic mode (i.e., the molecule). A decay operator acting on the two-level system describes phenomenologically probability losses. Finally, the temperature of the molecule is controlled by means of a Nosé-Hoover chain thermostat. A numerical study of the quantum dynamics of this toy model at different temperatures is reported. We find that the combined action of probability losses and thermal fluctuations assists quantum transport through the molecular junction. The possibility that the formalism here presented can be extended to treat both more quantum states (â¼10) and many more classical modes or atomic particles (â¼103-105) is highlighted.
RESUMO
BACKGROUND: Chemo-radiotherapy is standard of care in the treatment of unresectable stage III NSCLC. We aimed at assessing whether the addition of concurrent taxane-chemotherapy to thoracic irradiation following chemotherapy was able to improve treatment outcome. MATERIAL AND METHODS: In PITCAP trial, patients with unresectable stage III NSCLC were randomized to receive 2 cycles of platinum-paclitaxel followed by 60-61.2Gy thoracic irradiation (control arm) or by same radiotherapy with concomitant weekly paclitaxel (experimental arm). A literature-based meta-analysis including all studies with same design was also performed. RESULTS: At the time of the second interim analysis, when 151 patients were randomized, accrual was terminated. With a median follow-up of 6.1 years, median survival was 13.2 vs 15.1 months, with a 3-year survival rate of 19.5 vs 21.2% in the control and experimental arm, respectively (HR: 0.97; 95% CI 0.69-1.36; p=0.845). Treatment toxicity was manageable in both arms. The meta-analysis of 5 trials (n=866) confirmed the lack of a meaningful effect on 1-year overall survival of a taxane added concurrently to radiotherapy. CONCLUSIONS: These results do not support a meaningful survival benefit with the addition of single agent taxane given concurrently to radiotherapy after platinum-based induction in locally advanced NSCLC.
Assuntos
Antineoplásicos/administração & dosagem , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Terapia Combinada/métodos , Metanálise como Assunto , Paclitaxel/administração & dosagem , Taxoides/administração & dosagem , Adulto , Idoso , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Carboplatina/uso terapêutico , Feminino , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/uso terapêutico , Taxa de Sobrevida , Taxoides/uso terapêutico , Resultado do TratamentoRESUMO
Previous in vitro and in vivo studies showed a synergistic effect of concomitant doxorubicin and radiotherapy in a variety of solid tumors. From 1988 to 2000, we have investigated in a pilot study and then in a phase II study the efficacy of a concomitant doxorubicin radiotherapy treatment in patients with advanced and/or metastatic soft tissue sarcomas (STS). We enrolled and treated a group of 115 patients with advanced STS, with metastases (61%), frequently pretreated (59%), predominantly G2/G3 (84%). Doxorubicin was administered by continuous infusion at a dose of 12 mg/m(2)/day over 5 consecutive days concomitantly with radiotherapy; treatment was given on ambulatory basis at 2-week intervals with support of granulocytes colony stimulating factors (GCSF). In the whole group of 115 patients a clinical objective response (ORs) rate of 67% was obtained, with 11% complete and 56% partial responses. No patient progressed while on therapy, except one who progressed in non-irradiated metastatic tumor. Treatment (median 3 cycles) was well tolerated with no WHO grade 3 toxicity (apart from alopecia) and no acute or chronic cardiotoxicity. Thirty-nine responder patients underwent surgery (24 primary tumors, 10 relapses, 5 relapses plus isolated lung metastases). The median survival time(s) was 29 months in the whole series and over 50 months in responder patients. A multivariate analysis showed a positive association between survival and sex (HR=1.8; CI 95%, 1.0-3.4), performance status (HR=2.1; CI 95%, 1.1-4.0), ORs (HR=7.9; CI 95%, 3.5-18.1) and surgery (HR=8.8; CI 95%, 2.1-35.9). Low toxicity, high OR rate and positive survival time trend make the concomitant chemo-radiotherapy an efficacious approach for advanced STS.
Assuntos
Doxorrubicina/uso terapêutico , Sarcoma/tratamento farmacológico , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/radioterapia , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Sarcoma/secundário , Neoplasias de Tecidos Moles/patologia , Resultado do TratamentoRESUMO
Hepatocellular carcinoma (HCC) with extension or metastasis to the right atrium is an uncommon form of cardiac malignancy. This report describes a rare case of right intraventricular metastasis from HCC in a patient who had undergone a partial hepatectomy for HCC more than two years earlier. Open heart surgery was performed and the mass was partially excised. Symptoms (dyspnea, edema of the lower extremities, palpitations) improved after surgery. Two months later a recurrence of the ventricular mass was observed. Systemic chemotherapy with cisplatin and doxorubicin resulted in significant tumor reduction. The patient died of progressive hepatic failure six months later. In addition to this case report, a review of the literature on heart involvement from HCC is presented.