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1.
Opt Express ; 22(26): 32371-83, 2014 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-25607201

RESUMO

In this work a new technique for synthesizing metamaterials using Bézier surfaces is introduced. First, the computational efficiency for the optimization of a reconfigurable Bézier quarter-wave plate metasurface is compared to the popular technique of optimizing pixelized surfaces via a binary Genetic Algorithm (GA). For the presented design methodology, a real valued optimization technique is employed which is based on the Covariance Matrix Adaptation Evolutionary Strategy (CMA-ES). When compared to the GA, the optimizations of Bézier surfaces using CMA-ES are shown to consistently arrive at better solutions with an order of magnitude reduction in the required number of function evaluations. Additionally, more examples of Bézier metasurfaces are presented in the form of broadband quarter-wave and half-wave plate designs operating at optical wavelengths, subsequently exhibiting bandwidths which outperform metasurface designs found in the current literature.


Assuntos
Raios Infravermelhos , Dispositivos Ópticos , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Anisotropia , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento
2.
Opt Express ; 21(1): 1087-100, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23389002

RESUMO

This paper discusses a theoretical approach towards synthesizing broadband circularly polarizing reflectors. The broadband polarizing reflectors consist of birefringent metallo-dielectric metasurfaces which are described by the Jones matrices and verified via full-wave simulations. Specifically, full-wave simulations for candidate designs are presented that target operation in the near infrared band. In addition, reconfigurability is introduced and demonstrated for candidate designs at the long wave infrared band through the inclusion of a bistable phase change chalcogenide glass substrate.

3.
Prostate Cancer Prostatic Dis ; 16(1): 50-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22689129

RESUMO

BACKGROUND: Pomegranate juice has been associated with PSA doubling time (PSADT) elongation in a single-arm phase II trial. This study assesses biological activity of two doses of pomegranate extract (POMx) in men with recurrent prostate cancer, using changes in PSADT as the primary outcome. METHODS: This randomized, multi-center, double-blind phase II, dose-exploring trial randomized men with a rising PSA and without metastases to receive 1 or 3 g of POMx, stratified by baseline PSADT and Gleason score. Patients (104) were enrolled and treated for up to 18 months. The intent-to-treat (ITT) population was 96% white, with median age 74.5 years and median Gleason score 7. This study was designed to detect a 6-month on-study increase in PSADT from baseline in each arm. RESULTS: Overall, median PSADT in the ITT population lengthened from 11.9 months at baseline to 18.5 months after treatment (P < 0.001). PSADT lengthened in the low-dose group from 11.9 to 18.8 months and 12.2 to 17.5 months in the high-dose group, with no significant difference between dose groups (P = 0.554). PSADT increases >100% of baseline were observed in 43% of patients. Declining PSA levels were observed in 13 patients (13%). In all, 42% of patients discontinued treatment before meeting the protocol-definition of PSA progression, or 18 months, primarily due to a rising PSA. No significant changes occurred in testosterone. Although no clinically significant toxicities were seen, diarrhea was seen in 1.9% and 13.5% of patients in the 1- and 3-g dose groups, respectively. CONCLUSIONS: POMx treatment was associated with ≥ 6 month increases in PSADT in both treatment arms without adverse effects. The significance of this on-study slowing of PSADT remains unclear, reinforcing the need for placebo-controlled studies in this patient population.


Assuntos
Antineoplásicos/administração & dosagem , Lythraceae , Fitoterapia/métodos , Extratos Vegetais/uso terapêutico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue
4.
Prostate Cancer Prostatic Dis ; 15(3): 308-12, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22641239

RESUMO

BACKGROUND: Denosumab, a fully human monoclonal antibody against RANK ligand, increased bone mineral density (BMD) and reduced fracture risk vs placebo in a phase 3 trial in men with prostate cancer on androgen deprivation therapy (ADT). The present analysis of this study evaluated BMD changes after 36 months in responder subgroups and in individual patients for three key skeletal sites (lumbar spine (LS), femoral neck (FN) and total hip (TH)) and the distal radius. METHODS: Men with nonmetastatic prostate cancer receiving ADT were treated with subcutaneous denosumab 60 mg (n=734) or placebo (n=734) every 6 months for up to 36 months in a phase 3, randomized, double-blind study. Patients were instructed to take supplemental calcium and vitamin D. For this BMD responder analysis, the primary outcome measure was the percentage change in BMD from baseline to month 36 at the LS, FN and TH as measured by dual-energy X-ray absorptiometry. BMD at the distal 1/3 radius at 36 months was measured in a substudy of 309 patients. RESULTS: At 36 months, significantly more patients in the denosumab arm had increases of >3% BMD from baseline at each site studied compared with placebo (LS, 78 vs 17%; FN, 48 vs 13%; TH, 48 vs 6%; distal 1/3 radius, 40 vs 7% (P<0.0001 for all)). BMD loss at the LS, FN and TH occurred in 1% of denosumab-treated patients vs 42% of placebo patients, and BMD gain at all three sites occurred in 69% of denosumab patients vs 8% of placebo patients. Lower baseline BMD was associated with higher-magnitude BMD responses to denosumab at the LS, FN and TH. CONCLUSIONS: In men with prostate cancer receiving ADT, significantly higher BMD response rates were observed with denosumab vs placebo. Patients with lower baseline T-scores benefited the most from denosumab treatment.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Conservadores da Densidade Óssea/farmacologia , Densidade Óssea/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Denosumab , Humanos , Masculino , Pessoa de Meia-Idade , Ligante RANK/antagonistas & inibidores , Resultado do Tratamento
5.
J Urol ; 179(1): 152-5, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18001802

RESUMO

PURPOSE: We evaluated the effects of toremifene on bone mineral density, a surrogate for fracture risk, in men receiving androgen deprivation therapy for prostate cancer. MATERIALS AND METHODS: In an ongoing, multicenter, phase 3 fracture prevention study 1,392 men 50 years or older with prostate cancer receiving androgen deprivation therapy were randomized to 80 mg toremifene per day or placebo. Bone mineral density of the lumbar spine, total hip and femoral neck was assessed using dual energy x-ray absorptiometry. In this planned interim analysis of the first 197 subjects we compared bone mineral density changes from baseline to month 12 between the placebo and toremifene groups. RESULTS: Compared with the placebo group men in the toremifene group had significant increases in bone mineral density at each evaluated skeletal site. Lumbar spine bone mineral density decreased 0.7% in the placebo group and increased 1.6% in the toremifene group (between group comparison p <0.001). Total hip bone mineral density decreased 1.3% in the placebo group and increased 0.7% in the toremifene group (p = 0.001). Femoral neck bone mineral density decreased 1.3% in the placebo group and increased 0.2% in the toremifene group (p = 0.009). Between group differences in the change in bone mineral density from baseline to month 12 were 2.3%, 2.0% and 1.5% for the lumbar spine, total hip and femoral neck, respectively. CONCLUSIONS: Toremifene significantly increased hip and spine bone mineral density in men receiving androgen deprivation therapy for prostate cancer. The effect of toremifene on the fracture risk is being assessed in the ongoing randomized, controlled trial.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Densidade Óssea/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/agonistas , Orquiectomia , Neoplasias da Próstata/terapia , Toremifeno/farmacologia , Idoso , Humanos , Masculino
6.
Prostate Cancer Prostatic Dis ; 8(1): 75-83, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15685254

RESUMO

A randomized, double-blind, placebo-controlled multicenter trial involving 107 men receiving bicalutamide ('Casodex') 150 mg/day therapy following radical therapy for prostate cancer assessed tamoxifen ('Nolvadex') 20 mg/day and anastrozole ('Arimidex') 1 mg/day for the prophylaxis and treatment of gynecomastia/breast pain. Tamoxifen, but not anastrozole, significantly reduced the incidence of gynecomastia/breast pain when used prophylactically and therapeutically. Serum testosterone levels increased with tamoxifen relative to placebo but prostate-specific antigen levels declined in all treatment groups. Further studies are needed to define the optimum tamoxifen dose and to assess any impact on cancer control. The use of tamoxifen in this setting remains to be investigated.


Assuntos
Anilidas/efeitos adversos , Anilidas/uso terapêutico , Antineoplásicos Hormonais/efeitos adversos , Antineoplásicos Hormonais/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Doenças Mamárias/induzido quimicamente , Doenças Mamárias/prevenção & controle , Ginecomastia/induzido quimicamente , Ginecomastia/prevenção & controle , Nitrilas/efeitos adversos , Nitrilas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Tamoxifeno/uso terapêutico , Triazóis/efeitos adversos , Triazóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anastrozol , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Dor/induzido quimicamente , Dor/prevenção & controle , Placebos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Tamoxifeno/farmacologia , Testosterona/sangue , Compostos de Tosil , Resultado do Tratamento
7.
Plant Cell ; 12(5): 721-38, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10810146

RESUMO

A major structural component of the cuticle of plants is cutin. Analysis of the function of cutin in vivo has been limited because no mutants with specific defects in cutin have been characterized. Therefore, transgenic Arabidopsis plants were generated that express and secrete a cutinase from Fusarium solani f sp pisi. Arabidopsis plants expressing the cutinase in the extracellular space showed an altered ultrastructure of the cuticle and an enhanced permeability of the cuticle to solutes. In addition, pollen could germinate on fully differentiated leaves of cutinase-expressing plants but not on control leaves. These differences coincided with strong postgenital organ fusions. The junctions of the fusions contained pectic polysaccharides. As fused organs grew apart from each other, organ deformations and protrusions of epidermal cells developed at positions with high mechanical stress. These results demonstrate that an intact cutin layer not only is important for plant-environment interactions but also prevents fusions between different plant organs and is therefore necessary for normal epidermal differentiation and organ formation.


Assuntos
Arabidopsis/anatomia & histologia , Hidrolases de Éster Carboxílico/genética , Fusarium/enzimologia , Plantas Geneticamente Modificadas/anatomia & histologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/microbiologia , Sequência de Bases , Primers do DNA , Microscopia Eletrônica de Varredura , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/microbiologia
8.
Proc Natl Acad Sci U S A ; 96(20): 11664-9, 1999 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-10500234

RESUMO

Sexual reproduction is a salient aspect of plants, and elaborate structures, such as the flowers of angiosperms, have evolved that aid in this process. Within the flower the corresponding sex organs, the anther and the ovule, form the male and female sporangia, the pollen sac and the nucellus, respectively. However, despite their central role for sexual reproduction little is known about the mechanisms that control the establishment of these important structures. Here we present the identification and molecular characterization of the NOZZLE (NZZ) gene in the flowering plant Arabidopsis thaliana. In several nzz mutants the nucellus and the pollen sac fail to form. It indicates that NZZ plays an early and central role in the development of both types of sporangia and that the mechanisms controlling these processes share a crucial factor. In addition, NZZ may have an early function during male and female sporogenesis as well. The evolutionary aspects of these findings are discussed. NZZ encodes a putative protein of unknown function. However, based on sequence analysis we speculate that NZZ is a nuclear protein and possibly a transcription factor.


Assuntos
Arabidopsis/genética , Genes de Plantas , Proteínas Nucleares/genética , Sequência de Aminoácidos , Arabidopsis/fisiologia , Sequência de Bases , Evolução Biológica , Dados de Sequência Molecular , Mutação , Fenótipo , RNA Mensageiro/análise
9.
Biol Chem ; 379(1): 51-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9504717

RESUMO

The double strand binding protein A (DsbA) of bacteriophage T4 is one of several viral gene products participating in transcriptional regulation. These proteins interact or associate with the host RNA polymerase core enzyme, enabling the enzyme to successively initiate transcription at different classes of viral promoters: early, middle and late. This leads to a temporally controlled expression of the T4 gene products. The DsbA binding site overlaps the late promoter region, and DsbA binding seems to intensify transcription of late genes in vitro, possibly acting as an enhancer protein (Molecular Biology of Phage T4, Karam, 1994). To further investigate the function and structure of DsbA, we overexpressed the protein in E. coli and purified it to homogeneity. Physiological functionality of the recombinant protein was shown by gel retardation experiments and by circular dichroism (CD) spectroscopy. DsbA shows strong bands in the near UV-CD spectra. The far UV-CD spectroscopy analysis shows alpha-helices to be the main secondary structure elements. This is in agreement with secondary structure predictions. A possible helix-turn-helix motif in the center of the protein could be identified. Results from crosslinking and sedimentation analyses show that DsbA forms a dimer in solution. The thermal unfolding curve fits a dimer-two-state-folding-model, and the unfolding temperature was concentration dependent. Therefore, dimerization should supply the main portion of the free energy of stabilization of deltaG0 = 42 kJ/mol.


Assuntos
Proteínas de Ligação a DNA/química , Regulação Viral da Expressão Gênica/genética , Proteínas Virais/química , Sítios de Ligação , Proteínas de Ligação a DNA/fisiologia , RNA Polimerases Dirigidas por DNA/metabolismo , Dimerização , Escherichia coli/genética , Sequências Hélice-Volta-Hélice , Regiões Promotoras Genéticas/genética , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Temperatura , Termodinâmica , Fatores de Transcrição/química , Transcrição Gênica/genética , Proteínas Virais/fisiologia
10.
J Urol ; 159(4): 1232-3, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9507842

RESUMO

PURPOSE: We evaluate the use of finasteride to control gross hematuria secondary to prostatic bleeding. MATERIALS AND METHODS: We reviewed retrospectively 42 patients treated with finasteride to treat gross hematuria. RESULTS: There were 28 evaluable patients who had taken finasteride for at least 6 months to control gross hematuria and hematuria ceased in 25 (91%). In 1 patient clot retention developed requiring transurethral resection of the prostate and 2 patients had 1 or more minor episodes of bleeding that resolved spontaneously. CONCLUSIONS: Finasteride appears to be an effective agent for controlling gross hematuria secondary to prostatic bleeding.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Finasterida/uso terapêutico , Hematúria/tratamento farmacológico , Hemorragia/complicações , Doenças Prostáticas/complicações , Idoso , Idoso de 80 Anos ou mais , Hematúria/etiologia , Humanos , Masculino
11.
J Urol ; 158(3 Pt 1): 869-71, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9258101

RESUMO

PURPOSE: We initiated a prospective study to verify or refute the complications of lymphocele formation and excessive blood loss associated with heparin prophylaxis in pelvic lymphadenectomy and radical prostatectomy. MATERIALS AND METHODS: A prospective study was completed on 579 men undergoing pelvic lymphadenectomy usually in association with radical prostatectomy. Patients were assigned to group 1 (given preoperative and postoperative subcutaneous heparin) and group 2 (no heparin). All patients were evaluated 2 to 3 weeks after surgery with ultrasound for pelvic lymphocele. RESULTS: There was no statistically significant difference in the number or size of pelvic lymphoceles or blood loss in group 1 versus group 2. CONCLUSIONS: The use of heparin prophylaxis to prevent thromboembolic complications in conjunction with pelvic lymphadenectomy and radical prostatectomy is not associated with increased blood loss or increased rate of lymphocele formation.


Assuntos
Perda Sanguínea Cirúrgica , Fibrinolíticos , Heparina , Excisão de Linfonodo , Linfocele/induzido quimicamente , Complicações Pós-Operatórias/induzido quimicamente , Prostatectomia , Contraindicações , Humanos , Linfocele/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos
12.
J Urol ; 157(6): 2199-200, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9146614

RESUMO

PURPOSE: A retrospective review of a large group of transrectal ultrasound guided biopsies was performed to determine the symptomatic urinary tract infection rate associated with a consistent and defined antibiotic prophylaxis regimen. MATERIALS AND METHODS: A total of 4,439 biopsies was performed using an 18 gauge needle with ultrasound guidance. Patients were treated with 500 mg. ciprofloxacin twice daily for 8 doses beginning the day before biopsy. RESULTS: Of 5 symptomatic urinary tract infections noted 3 were complicated. CONCLUSIONS: These data demonstrate the low infection rate associated with this prophylaxis regimen.


Assuntos
Anti-Infecciosos/uso terapêutico , Antibioticoprofilaxia , Biópsia por Agulha/efeitos adversos , Ciprofloxacina/uso terapêutico , Próstata/patologia , Infecções Urinárias/prevenção & controle , Biópsia por Agulha/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia , Infecções Urinárias/epidemiologia , Infecções Urinárias/etiologia
13.
15.
J Urol ; 154(4): 1435-8, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7658552

RESUMO

PURPOSE: We assessed the use of combination bowel preparation before radical prostatectomy. MATERIALS AND METHODS: We reviewed 533 radical prostatectomies performed from 1984 to 1994. All patients underwent preoperative combination bowel preparation. The incidence, management and sequelae of rectal injury were determined. The literature addressing the management of rectal injuries was reviewed. RESULTS: Rectal injury occurred in 8 patients (1.5%). Injury was recognized intraoperatively and repaired primarily in 6 cases, and repair included colostomy in 2. Injury was recognized postoperatively as recto-urinary fistula in 2 cases and initial management was conservative. No fistula closed with conservative management. There were no pelvic abscesses and no deaths. CONCLUSIONS: Combination bowel preparation permits safe closure of rectal injury at radical prostatectomy without the necessity of routine colostomy. In the event of recto-urinary fistula, conservative management is not warranted.


Assuntos
Complicações Intraoperatórias/epidemiologia , Prostatectomia , Reto/lesões , Humanos , Incidência , Complicações Intraoperatórias/terapia , Masculino
16.
Phys Rev D Part Fields ; 49(12): 6864-6882, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10017008
17.
J Urol ; 151(2): 422, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8283543

RESUMO

Bladder necrosis is a rare entity in the urological literature. We report a case of bladder necrosis secondary to pelvic artery embolization to control intractable hemorrhage from a pelvic fracture.


Assuntos
Embolização Terapêutica/efeitos adversos , Fraturas Ósseas/complicações , Hemorragia/terapia , Ossos Pélvicos/lesões , Doenças da Bexiga Urinária/etiologia , Bexiga Urinária/patologia , Vísceras/irrigação sanguínea , Idoso , Artérias/lesões , Feminino , Humanos , Necrose/etiologia
18.
J Urol ; 151(1): 88-93, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7504748

RESUMO

Since 1989 we have used serum prostate specific antigen (PSA) levels as an indication for ultrasound guided systematic biopsies of the prostate. Realizing that the PSA level in part reflects prostatic glandular epithelial volume, we reviewed the accumulated data on our last 2,340 biopsies to determine if the quotient of PSA and prostatic volume, prostate specific antigen density, provided any further diagnostic information. There were evaluable data for 2,020 patients. Prostate specific antigen density levels are shown to have a strong correlation with the diagnosis of prostate cancer and provide a more reliable indication for ultrasound guided biopsy of the prostate than PSA alone.


Assuntos
Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Biópsia , Serviços de Saúde Comunitária , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue , Urologia
19.
J Cardiovasc Surg (Torino) ; 30(4): 544-6, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2674154

RESUMO

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) has not been reported as a complication of carotid endarterectomy. We present a case of SIADH in a patient who underwent carotid endarterectomy four weeks after a completed stroke with good recovery. The presence of this syndrome was associated with the development of a neurological deficit.


Assuntos
Doenças das Artérias Carótidas/cirurgia , Endarterectomia/efeitos adversos , Síndrome de Secreção Inadequada de HAD/etiologia , Constrição Patológica/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Traumatismo por Reperfusão/etiologia
20.
J Urol ; 139(5): 1066-7, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3361648

RESUMO

Desmopressin has been used as a hemostatic agent in numerous hematological and nonhematological diseases. We report a case of surgical hemorrhage secondary to prolonged bleeding time of unexplained origin controlled with desmopressin.


Assuntos
Tempo de Sangramento , Desamino Arginina Vasopressina/uso terapêutico , Hemorragia/tratamento farmacológico , Hemostasia Cirúrgica , Testes de Função Plaquetária , Complicações Pós-Operatórias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Nefrectomia
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