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1.
Int J Radiat Oncol Biol Phys ; 111(5): 1227-1236, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34418466

RESUMO

PURPOSE: Most new nasopharyngeal cancer cases occur in low-income and middle-income countries, and these patients experience poorer overall survival than that of new nasopharyngeal cancer cases in high-income countries. The goal of this research project is to determine whether the introduction of a radiation therapy quality assurance program can ultimately improve outcomes for nasopharyngeal cancer patients in lower-income and middle-income countries. This study reports the results of the first phase of the International Atomic Energy Agency Coordinated Research Project (325-E3-TM-47712). METHODS AND MATERIALS: This prospective study has 2 phases. Phase 1 is a survey of radiation therapy resources, patient characteristics and treatment, and results of radiation therapy quality assurance performed by the expert panel. An educational workshop reviewing phase 1 results for each center was completed before accrual of patients for phase 2. The ultimate aim of the study is to compare the first and second cohort of patients to see if quality assurance can result in fewer major protocol deviations and a 15% improvement in patients' 3-year progression-free survival. RESULTS: Of 14 participating centers, 13 (93%) had computed tomography simulators and linear accelerators (LINAC) with intensity modulated radiation therapy (IMRT) capacity, median 3 LINAC (range, 1-13), and median 10 radiation oncologists (range, 5-51). The annual number of nasopharyngeal cancer cases irradiated was median 54 (range, 10-627). Five of 14 centers (36%) had no local radiation therapy quality assurance. For the current phase 1 study, 134 patients were evaluated, 82.1% had MRI staging, 99.3% had metastatic workup, 65.6% undifferentiated histology, 51% stage 3 and 49% stage 4. Radiation therapy quality assurance revealed 81 (60.4%) of 134 patients had major protocol violations in gross tumor volume and high dose planning target volume contours and/or dosimetry, 28.4% patients had borderline plans, 15 (11.2%) acceptable, and only 6 (4.2%) had inevitable compromise due to tumor extent. CONCLUSIONS: This is the first International Atomic Energy Agency study to address the fundamental issue of treatment quality rather than altered treatment regimens. The high rate of unacceptable radiation therapy plans is a major concern, and we hope phase 2 will show a significant reduction and improved patient outcomes.


Assuntos
Neoplasias Nasofaríngeas , Energia Nuclear , Radioterapia de Intensidade Modulada , Países em Desenvolvimento , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/radioterapia , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
2.
Polymers (Basel) ; 13(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525384

RESUMO

The current study highlights a novel bio-sorbent design based on polyelectrolyte multi-layers (PEM) biopolymeric material. First layer was composed of sodium alginate and the second was constituted of citric acid and k-carrageenan. The PEM system was crosslinked to non-woven cellulosic textile material. Resulting materials were characterized using FT-IR, SEM, and thermal analysis (TGA and DTA). FT-IR analysis confirmed chemical interconnection of PEM bio-sorbent system. SEM features indicated that the microspaces between fibers were filled with layers of functionalizing polymers. PEM exhibited higher surface roughness compared to virgin sample. This modification of the surface morphology confirmed the stability and the effectiveness of the grafting method. Virgin cellulosic sample decomposed at 370 °C. However, PEM samples decomposed at 250 °C and 370 °C, which were attributed to the thermal decomposition of crosslinked sodium alginate and k-carrageenan and cellulose, respectively. The bio-sorbent performances were evaluated under different experimental conditions including pH, time, temperature, and initial dye concentration. The maximum adsorbed amounts of methylene blue are 124.4 mg/g and 522.4 mg/g for the untreated and grafted materials, respectively. The improvement in dye sorption evidenced the grafting of carboxylate and sulfonate groups onto cellulose surface. Adsorption process complied well with pseudo-first-order and Langmuir equations.

3.
Polymers (Basel) ; 13(3)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498334

RESUMO

The adsorption phenomenon using low-cost adsorbents that are abundant in nature is of great interest when the adsorbed capacity is significant. A newly designed natural polyelectrolyte multi-layered (PEM) biopolymeric system-based chitosan/modified chitosan polymer and functionalized cellulosic nonwoven material was prepared and used as an effective adsorbent for Reactive Red 198 (RR198) dye solutions. The bio-sorbent was characterized by FTIR, SEM, and thermal (TGA/DTA) analysis. The swelling behavior was also evaluated, showing the great increase of the hydrophilicity of the prepared adsorbent biopolymer. The effect of various process parameters on the performance of RR198 dye removal such as pH, contact time, temperature, and initial dye concentration was studied. The biopolymeric system has shown good efficiency of adsorption compared to other adsorbents based on chitosan polymer. The highest adsorption capacity was found to be 722.3 mgg-1 at pH = 4 (ambient temperature, time = 120 min and dye concentration = 600 mg L-1). The adsorption process fitted well to both pseudo-second-order kinetics and Freundlich/Temkin adsorption isotherm models. Regarding its low cost, easy preparation, and promising efficient adsorption results, this new concepted multi-layered bio-sorbent could be an effective solution for the treatment of industrial wastewater.

4.
Int J Phytoremediation ; 23(10): 1085-1094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33511852

RESUMO

In this work, powdered Calotropis gigantea seedpods were characterized and used as biosorbents of methylene blue dye from aqueous solution. FT-IR spectroscopy demonstrated functional groups characteristics of cellulose. Steric exclusion chromatography donated an average molecular weight of 230 kg/mol of the biopolymer. The polymolecularity index value (1.95) proved the good homogeneity of the polysaccharide. Scanning electron microscopy features displayed a homogenous morphology and porous structure. X-ray diffraction patterns showed peaks characteristics of cellulose and non-cellulose compositions. Thermogravimetric analysis/differential thermal analysis displayed exothermal decompositions at 316.9 °C and 456 °C. The maximum biosorption capacity of methylene blue was 88.36 mg/g at pH = 6, time = 60 min, and T = 21 °C. The level was comparable to some other studied agricultural wastes. The adsorption mechanism followed pseudo-second-order and Freundlich models. As it is abundant, available, low-cost, and easily recovered from solution, C. gigantea seedpods could be used as an effective biomaterial for the removal of organic pollutants from contaminated waters. Novelty statement: An abundant, available, and low-cost Calotropis gigantea seedpod was used, for the first time, as an effective biomaterial for the biosorption of organic pollutants. The biosorption level was found to be comparable to some other agricultural wastes studied previously in the literature.


Assuntos
Calotropis , Poluentes Químicos da Água , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno , Sementes , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Poluentes Químicos da Água/análise
5.
Surg Neurol Int ; 11: 352, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194285

RESUMO

BACKGROUND: Various hematological malignancies, including multiple myeloma, plasmacytoma, aggressive lymphoma, and indolent lymphoma, rarely result in spinal cord compression. METHODS: Here, we retrospectively analyzed 32 patients with multiple myeloma (50%), plasmacytoma (13%), aggressive lymphoma (28%), and indolent lymphoma (9%), resulting in spinal cord compression (2004 and 2016). Patients averaged 57 years of age and presented with the indolent onset of spinal cord compression (91% of cases) resulting mostly in motor deficits (69%). RESULTS: Local treatment modalities included radiotherapy (RT) (28%) alone, decompressive surgery (28%) alone, or decompressive surgery with consolidation RT (40%). The 1-year overall survival was 70%, and the progression-free survival frequency was 62%. CONCLUSION: This study highlighted the importance of standardizing the indications for RT alone versus RT with surgery depending on the patient's underlying pathological diagnosis, neurological deficits, and radiological findings.

6.
Rep Pract Oncol Radiother ; 25(3): 436-441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32372884

RESUMO

AIM: The objective of the study was to estimate the cumulative incidence (CI) of relapse, relapse-free survival (RFS) and overall survival (OS) in ALL patients after a once-a-day fractionated TBI (F-TBI) regimen with 9.9 Gy. The secondary objectives were evaluation of short and long-term toxicity and non-relapse mortality (NRM). BACKGROUND: Total body irradiation (TBI), as a part of the conditioning regimen before allogeneic stem cell transplantation (ASCT) for acute lymphoblastic leukemia (ALL), allows disease control by eradicating residual blast cells in the transplant recipient. MATERIALS AND METHODS: Retrospective study conducted in patients with ALL who received between March 2003 and December 2013 a conditioning regimen with F-TBI and chemotherapy. Irradiation was delivered with 3.3 Gy once-a-day for three consecutive days. RESULTS: Eighty-seven patients were included. The median age was 19 years (range: 5-49 years). The 3-year CI of relapse was 30%. The estimated 3-year RFS and OS were 54% and 58%, respectively. Cumulative incidence of acute graft-versus-host disease (aGVHD) grade II-IV and chronic GVHD (cGVHD) was 31% and 40%, respectively. Interstitial pneumonitis was observed in 2 patients. The 3-year CI of NRM was 16%. In multivariate analysis, cGVHD was associated with a lower CI of relapse (RR = 0.26, 95% CI: 0.07-0.95, p = 0.04). High-risk cytogenetics was associated with a lower RFS (RR = 2, 95 CI: 1.04-3.84, p = 0.03). Grade II-IV aGVHD was an independent predictor of higher CI of NRM (RR = 6.7, 95% CI: 1.4-31.7, p = 0.02). CONCLUSIONS: Once-a-day F-TBI regimen is effective, safe and practical in patients who underwent ASCT for ALL.

7.
Tunis Med ; 96(12): 911-931, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31131872
8.
Radiother Oncol ; 116(1): 21-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26163093

RESUMO

BACKGROUND: To optimize palliation in incurable locally advanced non-small cell lung cancer (NSCLC), the International Atomic Energy Agency conducted a prospective randomized study (NCT00864331) comparing protracted palliative radiotherapy (RT) course with chemotherapy (CHT) followed by short-course palliative RT. METHODS AND MATERIALS: Treatment-naive patients with histologically confirmed NSCLC, stage IIIA/IIIB, received either 39Gy in 13 fractions as RT alone (arm A, n=31) or 2-3 platinum-based CHT cycles followed by 10Gy in a single fraction or 16Gy in 2 fractions separated by one week (arm B, n=34). Primary outcome was overall survival. RESULTS: Treatment groups were balanced with respect to various variables. Median survival for all 65 patients was 8months, while median survival was 7.1 and 8.1months for the two arms, respectively (log-rank p=0.4 by study arm, and p=0.6 by Cox regression and stratified by country and sub-stage). One and three year survival rates for the two arms were 29%, and 9% and 41%, and 6%, respectively. There were no differences in any of the following endpoints: any failure, local failure, regional failure, contralateral thoracic failure, and distant failure between the two arms. High-grade (⩾3) toxicity was similar between the two arms. Symptoms, adverse events of any kind, KPS and body-mass index, were not different during treatment and during follow-up. There was no grade 5 toxicity. CONCLUSIONS: This incomplete and underpowered trial only hinted similar outcome between the treatment arms. Therefore, combined CHT-RT can perhaps be considered, in limited resource setting, where access to RT remains inadequate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Cuidados Paliativos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Agências Internacionais , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Energia Nuclear , Estudos Prospectivos , Taxa de Sobrevida
10.
Tunis Med ; 88(10): 714-20, 2010 Oct.
Artigo em Francês | MEDLINE | ID: mdl-20890818

RESUMO

BACKGROUND: the tumours of the pineal region are rare brain tumours, most common in children and characterized by a large clinical and histologic polymorphism. AIM: to assess the outcome and prognostic factors of 40 patients with primitive pineal region tumours treated at the department of radiotherapy of Salah Azaiz institute. METHODS: between January 1977 and December 2000, 40 patients received radiotherapy. There were 22 adults and 18 children (age < 16 years). The mean age was 20.4 years and sex ratio was 2.07. Histologic diagnosis was confirmed in 11 cases; 16 patients had a CT evaluation after 20 Gy radiotherapy and in 13 cases diagnosis was performed with CT aspects ± germinal tumour markers. Target volume varied; 10 had craniospinal irradiation, 16 had local irradiation and 14 had whole brain irradiation with a boost at the tumour bed. Chemotherapy was proposed for metastases and recurrent diseases. RESULTS: survival rates were 87% at 2 years and 74, 5% at 5 years. For children, survival rates were 88% at 2 and 4 years. Eight patients (20%) failed locally and 5 patients (12.5%) had metastasis. Age, performance status and large fields of radiotherapy seem to be associated with prognosis and survival. CONCLUSION: Pineal tumours and especially germinal tumours are chemosensitive and radiosensitive, care of these tumours is multidisciplinary involving surgery, chemotherapy and radiotherapy. From our study and a review of the literature, we tried to find a therapeutic strategy for tumours of the pineal region.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Glândula Pineal/patologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
11.
Tunis Med ; 87(12): 814-7, 2009 Dec.
Artigo em Francês | MEDLINE | ID: mdl-20209847

RESUMO

AIM: This study evaluated the prognostic value of the Para pharyngeal space involvement in nasopharyngeal carcinoma T 2 disease (UICC 1997 classification). METHODS: From January 1997 and December2001; 32 patients with nasopharyngeal carcinoma were examined by CT scan and according to the 1997 International Union Against Cancer (UICC) staging system, 15 had stage T2a M0 (G1) and 17 T2bM0(G2). The median age was 47 years. The male to female ratio was 1.81 (G1); 4.3 (G2). All patients were pathologically confirmed by biopsy from the nasopharynx as having UCNT in 100% (G1) and 94% (G2). The node involvement was 52% for the G1 (N2: 26%, N3: 26%) and 80% for the G2 (N2: 47%, N3: 41%). Both neoadjuvant chemotherapy and radiotherapy were performed for advanced N disease and only radiotherapy for NO. RESULTS: Examination and CT scan were performed for the evaluation of the treatement. The completely clinical remission after chemotherapy was 12.5% (G1) and 53% (G2), partial remission was 25% (G1) and 35% (G2). The CT scan control wasn't performed for all patients. The complete response was 69% (G1) and 53% (G2); partial response was 6% for both two groups. The median follow up was 79 months. Disease free survival rates were 70% for G1 (T2a) and 48% for G2 (T2b). Distant metastasis rates were 26% (G1) vs 6% (G2) and more likely in the presence of advanced N disease. Five years overall survival was 78% (G1) T2a vs. 55% (G2) T2b.The N disease was correlated to metastasis as overall survival was 66.7% for N3 disease vs 85.7% for N0. CONCLUSION: Parapharyngeal tumor involvement affects local and regional tumor failure. Subclassification of T2 disease into T2a/T2b should have an impact on treatment strategies.


Assuntos
Carcinoma/mortalidade , Carcinoma/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Nasofaringe/patologia , Carcinoma/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/terapia , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos
12.
Tunis Med ; 83(10): 581-5, 2005 Oct.
Artigo em Francês | MEDLINE | ID: mdl-16370205

RESUMO

The radiotherapy department at Salah Azaïz institute had started, in March 2000, a new sophisticated technique of irradiation consisting in total body irradiation (TBI). TBI is used in many preparative regimens before bone marrow transplantation in the treatment of haematological malignancies. TBI aims to destroy immunocompetent tissues in order to avoid graft rejection and to eradicate residual tumor cells. In this article, we review different TBI techniques and its main indications. We also describe the acute and late effects of TBI.


Assuntos
Transplante de Medula Óssea , Irradiação Corporal Total/métodos , Rejeição de Enxerto , Humanos , Irradiação Corporal Total/efeitos adversos
13.
Tunis Med ; 83(3): 146-9, 2005 Mar.
Artigo em Francês | MEDLINE | ID: mdl-15929442

RESUMO

This is a retrospective study of patients treated for cervix cancer staged IB2, IIA or IIB with bulky tumor (> 4cm). Treatment was concurrent radiotherapy (45Gy with 1,8Gy daily fraction) and chemotherapy (5 cycles of Platinum 40mg/m2/week). All patients underwent Brachytherapy (15Gy on the reference isodose according to Paris system) followed by surgery (radical abdominal hysterectomy and bilateral pelvic lymphadenectomy: Piver 3) Between October 1999 and December 2002, forty five patients were treated in this protocol. Median age was 46 years (21- 68). Histology was squamous cell carcinoma in 93% and glandular carcinoma in 7%. Average external radiation dose was 44Gy (20-50). Ninety three percent of patients had at least 3 cycles of chemotherapy and 46,5% received the planned 5 cycles. On the operative specimens, there was 62,5% complete response and only 7 pelvic node involvement (17,5%). Four postoperative complications were noted (one vascular injury, one urinary fistula, one phlebitis and one lymph collection). Preoperative combined radiotherapy and chemotherapy in the early bulky stages of uterine cervix cancer is well tolerated and "gives" a high rate of sterilisation. There was no increase in surgical morbidity.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias do Colo do Útero/terapia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Braquiterapia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Colo do Útero/patologia , Cisplatino/uso terapêutico , Radioisótopos de Cobalto/uso terapêutico , Terapia Combinada , Feminino , Humanos , Histerectomia , Excisão de Linfonodo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Dosagem Radioterapêutica , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia
14.
Rev Neurol (Paris) ; 160(5 Pt 1): 539-45, 2004 May.
Artigo em Francês | MEDLINE | ID: mdl-15269671

RESUMO

AIMS: To determine local control and overall survival rates of 14 patients treated for a grade III or IV glioma relapsing in a previously irradiated area and re-irradiated by stereotactic radiosurgery. PATIENTS AND METHODS: From January 1997 to October 2001, 14 patients (median age 52 Years, age range 49-58 Years, Karnofski performance score 80 to 100) received radiosurgery for a relapse of grade III (3 patients) and or grade IV (10 patients) malignant gliomas. Before relapse, all patients had undergone surgery and had been given with a classical radiation protocol. Median maximum diameter and Volume of the tumors were 38.5mm (24-86mm) and 7cm3 (2-35cm3), respectively. RESULTS: Median maximal dose at the isocenter and median minimal dose at the periphery of the lesion were 21Gy (16-38Gy) and 13Gy (9-17Gy), respectively. Mean follow-up was 8.5 Months (1-29). Median overall survival was 11.6 Months; 6-Month, 1- and 2-Year overall survival rates were 85p.100, 36p.100 and 12p.100, respectively. At univariate analysis, only histological grade was a significant prognostic factor of overall survival (p=0.03). Median disease-free survival was 8.2 Months while 6-Month and 1-Year disease-free survival rates were 69p.100 and 14p.100, respectively. According to univariate analysis, histological grade (p=0.033) and minimal dose delivered at the margin of the target Volume (p=0.02) were prognostic factors for disease-free survival. Two patients developed a symptomatic radionecrosis. CONCLUSION: Radiosurgery of relapsed primitive high-grade brain tumors is efficient and overall survival rates were encouraging.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Radiocirurgia , Terapia de Salvação , Neoplasias Encefálicas/patologia , Feminino , Seguimentos , Glioma/patologia , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Necrose , Recidiva Local de Neoplasia , Prognóstico , Doses de Radiação , Radiocirurgia/efeitos adversos , Análise de Sobrevida
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