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1.
Sci Rep ; 13(1): 14840, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684256

RESUMO

In this work, we present a new approach to retrieve the optical phase map of an object which is projected by a single differentiated two-beam interference pattern. This approach is based on the differentiation of the intensity equation of the two-beam interference with respect to the carrier's phase angle. Therefore, two interference patterns which are shifted by a very small phase angle can be obtained. Then, these two patterns are projected on the object. By exploiting the definition of the mathematical differentiation, the optical phase object's variations are retrieved from the recorded intensity distributions of both projected patterns. According to this method, the extracted optical phase angles are raised as an inverse "sin" function. This means that the unwrapping process of this function limits the recovered phase angles between - π/2 and π/2. So, the unwrapping process of these unusual wrapped phase angles is explained. The proposed method is applied on (a) two objects which are simulated by combinations of multiple Gaussian functions and (b) a 3D real object. It is found that the inclination of the projected interference pattern on the object redistributes the intensity distribution due to the Lamber's "cos" aw of illumination. This effect is considered in the retrieving process of the object's phase map. The limitations of the presented method are discussed and the obtained results are found promising.

2.
J Microsc ; 262(1): 73-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26588671

RESUMO

In this paper, we introduced a mathematical method for measuring the optical path length differences (OPDs), which is suitable for large OPD values where the fringes connections are difficult to detect. The proposed method is based on varying the width of the fringes, without changing the wavelength of the used coherent source. Also, in this work, we discussed the need for such method in off-axis phase-shifting digital holography. Low-resolution off-axis holograms failed to detect the correct interference order. In general, off-axis phase-shifting digital holography is limited by the resolution of the captured holograms. The results obtained using our proposed technique were compared to the results obtained using off-axis phase-shifting digital holograms and conventional two-beam interferometry. Holograms were given for illustration.

3.
J Microsc ; 257(3): 208-16, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25511668

RESUMO

In this paper, we present a nonray-tracing technique for evaluating the three dimensional distribution of the refractive index values inside polymeric fibres. This technique, named 'single-frame computed-tomography (SFCT)', is applied to digital holography. A comparative study between the calculated optical phase values using ordinary tomography and SFCT is carried out, and a negligible deviation is detected. The proposed technique is used to determine the three-dimensional refractive index profile of isotactic Polypropylene fibres, IPP. The variation of the optical properties is measured before, during and after the formation of the necking phenomenon. In addition, SFCT technique is applied to the online determination of the change of the optical properties of IPP fibres. Holograms are given for illustration.

4.
Appl Opt ; 53(31): 7462-9, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25402912

RESUMO

We present a significant contribution to the theory of determining the refractive index profile of a bent homogenous optical fiber. In this theory we consider two different processes controlling the index profile variations. The first is the linear index variation due to stress along the bent radius, and the second is the release of this stress on the fiber surface. This release process is considered to have radial dependence on the fiber radius. These considerations enable us to construct the index profile in two dimensions normal to the optical axis, considering the refraction of light rays traversing the fiber. This theory is applied to optical homogenous bent fiber with two bending radii when they are located orthogonal to the light path of the object arm in the holographic setup (like the Mach-Zehnder interferometer). Digital holographic phase shifting interferometry is employed in this study. The recorded phase shifted holograms have been combined, reconstructed, and processed to extract the phase map of the bent optical fiber. A comparison between the extracted optical phase differences and the calculated one indicates that the refractive index profile variation should include the above mentioned two processes, which are considered as a response for stress distribution across the fiber's cross section. The experimentally obtained refractive index profiles provide the stress induced birefringence profile. Thus we are able to present a realistic induced stress profile due to bending.

5.
J BUON ; 18(2): 425-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23818356

RESUMO

PURPOSE: This study was undertaken to determine the effect of adjuvant chemotherapy combined with reduced-dose craniospinal irradiation (CSI) on survival and neurocognitive sequelae of radiotherapy (RT) in patients with average- risk medulloblastoma above the age of 3 years. METHODS: Thirty-three children between 3 and 10 years of age with average-risk medulloblastoma were treated with postoperative reduced-dose CSI (24.0 Gy) and 30.6 Gy of local RT (total of 54.6 Gy) and then with adjuvant chemotherapy consisting of cisplatin, vincristine, and cyclophosphamide every 4 weeks for 8 cycles. RESULTS: At 5 years, event-free survival (EFS) was 79%, while overall survival (OS) was 85%. Sites of relapse were local in 3%, neuraxis in 9% and both local and neuraxis in 9% of the patients. Chemotherapy was well tolerated. Hematopoietic toxicity was the most predominant side effect followed by vomiting and ototoxicity. No grade III or IV nephrotoxicity or neurotoxicity and no treatment-related deaths were encountered. Insignificant decline of intelligence quotient (IQ) was reported in 28.6% of the patients. CONCLUSION: The preliminary results of adjuvant chemotherapy after reduced-dose CSI in average-risk medulloblastoma patients are encouraging and effective, and can be applied safely with acceptable toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Cerebelares/terapia , Quimiorradioterapia Adjuvante , Irradiação Craniana , Meduloblastoma/terapia , Doses de Radiação , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Cerebelares/mortalidade , Neoplasias Cerebelares/patologia , Quimiorradioterapia Adjuvante/efeitos adversos , Criança , Pré-Escolar , Cisplatino/administração & dosagem , Cognição/efeitos dos fármacos , Cognição/efeitos da radiação , Irradiação Craniana/efeitos adversos , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Meduloblastoma/mortalidade , Meduloblastoma/secundário , Recidiva Local de Neoplasia , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Vincristina/administração & dosagem
6.
Indian J Cancer ; 49(1): 169-75, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22842184

RESUMO

AIM: The aim of this Phase II study was to evaluate the activity and safety of biweekly pegylated liposomal doxorubicin (PLD) and oxaliplatin (L-OHP) in patients with platinum-taxane resistant ovarian cancer. MATERIALS AND METHODS: Treatment consisted of PLD (20 mg/m²) on Day 1; and L-OHP (50 mg/m²) administered on Days 1 and 2, every two weeks. Response to therapy was assessed using the Response Evaluation Criteria in Solid Tumors RECIST ; toxicity was evaluated by the National Cancer Institute Common Toxicity Criteria. RESULTS: Forty patients pretreated with platinum/taxane chemotherapy, with a median age of 61 years, were recruited for the study. Thirty-eight patients were available for response evaluation: three complete responses and nine partial responses were registered; resulting in an overall response rate of 31.5%. Twenty-eight patients gained clinical benefit (73.7%) from this chemotherapy regimen. Median time to progression (TTP) and overall survival (OS) were 5.5 and 10 months respectively. The hematological and non-hematological toxicity profile was favorable. No Grade 4 toxicity was observed. Major toxicities included Grade 3 neutropenia (13.2%), Grade 2 palmar-plantar erythrodysesthesia (7.9%), and Grade 1-2 neuropathy in 15.8% of patients. CONCLUSION: Biweekly PLD and L-OHP combination has high activity, with less than anticipated adverse toxicity, for treatment of platinum-resistant ovarian cancer. A comparison of the doublet PLD/L-OHP with single-agent treatment is warranted.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Compostos Organoplatínicos/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Doxorrubicina/efeitos adversos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Pessoa de Meia-Idade , Compostos Organoplatínicos/efeitos adversos , Neoplasias Ovarianas/patologia , Oxaliplatina , Análise de Sobrevida , Taxoides/administração & dosagem
7.
J BUON ; 17(2): 254-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22740202

RESUMO

PURPOSE: The purpose of this study was to prospectively evaluate the efficacy and toxicity of cisplatin and ifosfamide combination chemotherapy in metastatic triple negative breast cancer (TNBC) previously treated with anthracyclines and taxanes. METHODS: Patients were treated with cisplatin 20 mg/ m2 iv, days 1-5, over 30 min and ifosfamide 1200 mg/m(2) iv, days 1-5 over 2 h with mesna uroprotection. Therapy was repeated every 3 weeks. Responding patients received a maximum of 6 cycles of chemotherapy. Treatment was delayed in the event of grade 3 or higher hematologic or non hematologic toxicity until resolution to grade 2 or less. Treatment then proceeded as scheduled but with 20% dose reduction of both drugs. RESULTS: 40 TNBC patients were enrolled. Median age was 43 years (range 37-49). Thirty (75%) patients had visceral involvement. Fourteen (35%) patients achieved objective response, disease stabilization occurred in 2 (5%) patients, while disease progression occurred in 24 (60%) patients. Grade 3/4 neutropenia occurred in 11 (27.5%) patients, while grade 3/4 thrombocytopenia was registered in 9 (22.5%) patients. Neurosensory toxicity was the commonest non hematologic acute severe toxicity (10%). With a median follow up of 14 months the median time to progression was 6 months and the median overall survival 12 months. Survival of responding patients was significantly better compared with non responders (p=0.000). CONCLUSION: Our outpatient cisplatin / ifosfamide regimen displayed reasonable efficacy and toxicity in TNBC. However, the outcome did not differ from relevant studies in the literature. Further molecular studies and phase III trials are still needed to further improve treatment strategies in TNBC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Terapia de Salvação , Adulto , Antraciclinas/administração & dosagem , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Cisplatino/administração & dosagem , Feminino , Seguimentos , Humanos , Ifosfamida/administração & dosagem , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Prospectivos , Taxa de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento
8.
Med Oncol ; 29(2): 454-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21350875

RESUMO

Due to socioeconomic issues, locally advanced breast cancer (LABC) is still a common presentation of breast cancer in the third world. It was found that LABC patients showing a clinical response after two to four cycles of neoadjuvant chemotherapy have a higher probability of obtaining a pathological complete response at surgery than patients without an early response. In the present work, the short-term effects and toxicity of the neoadjuvant second-line vinorelbine and gemcitabine combination were evaluated in the treatment of LABC who did not show early response to anthracyclines and taxanes-containing regimen. The use of vinorelbine and gemcitabine was based on their use in metastatic breast cancer cases who had been treated before with anthracyclines and taxanes. This was a prospective phase II study accomplished at the Clinical Oncology and Nuclear Medicine Department of Mansoura University, Egypt. Seventy LABC patients not suitable for breast conservative surgery who failed to achieve early response to two cycles of a combination of docetaxel, doxorubicin, and cyclophosphamide (TAC) were treated with a 3-weekly regimen of vinorelbine 30 mg/m(2) plus gemcitabine 1,200 mg/m(2) given on days 1 and 8 by intravenous infusion as a second-line neoadjuvant chemotherapy. Response was assessed after the second cycle. Stable and progressed patients were operated upon while responding cases received up to four cycles before the operation. Patient accrual was from June 20, 2007, to October 20, 2009. The objective response was evaluated clinically with breast sonography before every new cycle and before operation while the pathological response was determined postoperatively. The toxicity was evaluated according to the National Cancer Institute--Common Toxicity criteria version 3. The end points of this study were clinical response rate, pathological response rate, and treatment toxicity. Clinical response rate was achieved in 35 cases (50%) while pathological response rate was reported in 4 cases (5.7%). Breast conservative surgery (BCS) became possible in 31 cases (44%). The most common severe toxicities (grades 3 and 4) were neutropenia and thrombocytopenia in 25.7 and 22.8% of cases, respectively. Toxicities were reversible and did not cause death. It is possible to achieve objective clinical and pathological responses of LABC with potentially non-cross-resistant neoadjuvant second-line therapy, leading to BCS in a high proportion of patients. Thus, preoperative second-line chemotherapy appears to be justified when breast conservation is an important treatment goal.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Lobular/tratamento farmacológico , Terapia Neoadjuvante , Terapia de Salvação , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Ciclofosfamida/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Docetaxel , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Taxoides/administração & dosagem , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina , Gencitabina
9.
Am Fam Physician ; 63(11): 2201-8, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11417772

RESUMO

People with valvular heart disease are living longer, with less morbidity, than ever before. Advances in surgical techniques and a better understanding of timing for surgical intervention account for increased rates of survival. Echocardiography remains the gold standard for diagnosis and periodic assessment of patients with valvular heart disease. Generally, patients with stenotic valvular lesions can be monitored clinically until symptoms appear. In contrast, patients with regurgitant valvular lesions require careful echocardiographic monitoring for left ventricular function and may require surgery even if no symptoms are present. Aside from antibiotic prophylaxis, very little medical therapy is available for patients with valvular heart disease; surgery is the treatment for most symptomatic lesions or for lesions causing left ventricular dysfunction even in the absence of symptoms.


Assuntos
Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/terapia , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/mortalidade , Insuficiência da Valva Aórtica/terapia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/terapia , Ecocardiografia , Feminino , Doenças das Valvas Cardíacas/mortalidade , Humanos , Masculino , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/terapia , Prolapso da Valva Mitral/diagnóstico , Prolapso da Valva Mitral/mortalidade , Prolapso da Valva Mitral/terapia , Estenose da Valva Mitral/diagnóstico , Estenose da Valva Mitral/mortalidade , Estenose da Valva Mitral/terapia , Exame Físico/métodos , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento
10.
Phytother Res ; 14(4): 284-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10861975

RESUMO

GC/MS analysis of the volatiles produced by the action of endogenous myrosinase in Cleome chrysantha Decne. herb, showed three major components, 1-isocyano-4-methyl benzene, gamma-muurolene and (cis) nerolidole (21.72%, 12.15% and 10.39%, respectively). 1-isocyano-4-methyl benzene is not produced from myrosinase treated seeds of Cleome chrysantha Decne., while muurolene and nerolidole were found at higher concentrations 16.1% and 13.67%, respectively. Some other isothiocyanates identified in the seeds and leaves, but in low percentages, were 2-methylbutyl isothiocyanate, 4-methylthiobutyl isothiocyanate and isothiocyanatomethyl benzene. Enzymatic hydrolysis of the ethanol extract of Cleome chrysantha Decne., produced two non-volatile isothiocyanates, 4, 6-dimethyltetrahydro-1,3-oxazine-2-thione and N-(-4-methyl-sulphinyl-3-butenyl) isothiocyanate which was established by aniline and methanolic ammonia to give the stable form of phenyl thiourea. They were identified by their spectroscopic data. These two isothiocyanates and the volatiles of the herb showed good antimicrobial activity against E. coli, Pseudomonas putida and Rhizobium meloloti (gram-negative bacteria) and moderate activity against Bacillus subtilis and Streptococcus lactis (gram-positive bacteria).


Assuntos
Glicosídeo Hidrolases/metabolismo , Isotiocianatos/análise , Extratos Vegetais/farmacologia , Plantas/química , Antibacterianos , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Isotiocianatos/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Saccharomyces cerevisiae/efeitos dos fármacos
11.
Am Fam Physician ; 61(4): 1047-52, 1054, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10706157

RESUMO

Thyroiditis is a group of inflammatory thyroid disorders. Patients with chronic lymphocytic thyroiditis (also referred to as Hashimoto's thyroiditis) present with hypothyroidism, goiter, or both. Measurement of serum thyroid autoantibodies and thyroglobulin confirms the diagnosis. Subacute granulomatous thyroiditis (sometimes referred to as de Quervain's disease) is a self-limited but painful disorder of the thyroid. Physical examination, elevated erythrocyte sedimentation rate, elevated thyroglobulin level and depressed radioactive iodine uptake (RAIU) confirm the diagnosis. Subacute lymphocytic thyroiditis (silent thyroiditis) is considered autoimmune in origin and commonly occurs in the postpartum period. Symptoms of hyperthyroidism and depressed RAIU predominate. Acute (suppurative) thyroiditis is a rare, infectious thyroid disorder caused by bacteria and other microbes. The rare, invasive fibrous thyroiditis (Riedel's thyroiditis) presents with a slowly enlarging anterior neck mass that is sometimes confused with a malignancy.


Assuntos
Tireoidite/diagnóstico , Tireoidite/terapia , Diagnóstico Diferencial , Humanos , Educação de Pacientes como Assunto , Materiais de Ensino , Tireoidite/classificação , Tireoidite/epidemiologia , Tireoidite Autoimune/diagnóstico , Tireoidite Autoimune/terapia , Tireoidite Subaguda/diagnóstico , Tireoidite Subaguda/terapia
14.
Eur Arch Otorhinolaryngol ; 252(4): 239-43, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7546680

RESUMO

The ultrastructure of preserved ossicles at different shelf lives was compared. Homograft ossicles were harvested and preserved in 70% alcohol, 1:5000 Cialit (sodium-2-ethyl-mercuri-mercapto-benzoxazole-5-carboxylate), and buffered 4% formaldehyde at pH 7. The ultrastructure of each ossicle was studied by both scanning and transmission electron microscopy and was compared to that of fresh controls placed in 0.9 N saline solution. The results indicated clearly the superiority of 70% alcohol as a long-term preservative and 1:5000 Cialit as a short-term preservative.


Assuntos
Ossículos da Orelha/transplante , Preservação de Tecido/métodos , Cialit , Colágeno/ultraestrutura , Ossículos da Orelha/patologia , Etanol , Formaldeído , Sobrevivência de Enxerto/fisiologia , Humanos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Cloreto de Sódio
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