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1.
J Phys Chem B ; 127(13): 3079-3090, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36951605

RESUMO

It has been hypothesized that liquid polyamorphism, the existence of multiple amorphous states in a single-component substance, may be caused by molecular or supramolecular interconversion. A simple microscopic model [Caupin and Anisimov, Phys. Rev. Lett. 2021, 127, 185701] introduces interconversion in a compressible binary lattice to generate various thermodynamic scenarios for fluids that exhibit liquid polyamorphism and/or water-like anomalies. Using this model, we demonstrate the dramatic effects of interconversion on the interfacial properties. In particular, we find that the liquid-vapor surface tension exhibits either an inflection point or two extrema in its temperature dependence. Correspondingly, we observe anomalous behavior of the interfacial thickness and a significant shift in the location of the concentration profile with respect to the location of the density profile.

2.
Proc Natl Acad Sci U S A ; 120(1): e2215012120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36580588

RESUMO

The separation of substances into different phases is ubiquitous in nature and important scientifically and technologically. This phenomenon may become drastically different if the species involved, whether molecules or supramolecular assemblies, interconvert. In the presence of an external force large enough to overcome energetic differences between the interconvertible species (forced interconversion), the two alternative species will be present in equal amounts, and the striking phenomenon of steady-state, restricted phase separation into mesoscales is observed. Such microphase separation is one of the simplest examples of dissipative structures in condensed matter. In this work, we investigate the formation of such mesoscale steady-state structures through Monte Carlo and molecular dynamics simulations of three physically distinct microscopic models of binary mixtures that exhibit both equilibrium (natural) interconversion and a nonequilibrium source of forced interconversion. We show that this source can be introduced through an internal imbalance of intermolecular forces or an external flux of energy that promotes molecular interconversion, possible manifestations of which could include the internal nonequilibrium environment of living cells or a flux of photons. The main trends and observations from the simulations are well captured by a nonequilibrium thermodynamic theory of phase transitions affected by interconversion. We show how a nonequilibrium bicontinuous microemulsion or a spatially modulated state may be generated depending on the interplay between diffusion, natural interconversion, and forced interconversion.


Assuntos
Simulação de Dinâmica Molecular , Termodinâmica
3.
J Chem Phys ; 157(10): 101101, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36109224

RESUMO

Fluid polyamorphism, the existence of multiple amorphous fluid states in a single-component system, has been observed or predicted in a variety of substances. A remarkable example of this phenomenon is the fluid-fluid phase transition (FFPT) in high-pressure hydrogen between insulating and conducting high-density fluids. This transition is induced by the reversible dimerization/dissociation of the molecular and atomistic states of hydrogen. In this work, we present the first attempt to thermodynamically model the FFPT in hydrogen at extreme conditions. Our predictions for the phase coexistence and the reaction equilibrium of the two alternative forms of fluid hydrogen are based on experimental data and supported by the results of simulations. Remarkably, we find that the law of corresponding states can be utilized to construct a unified equation of state combining the available computational results for different models of hydrogen and the experimental data.

4.
Phys Rev E ; 106(1-2): 015305, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35974620

RESUMO

We suggest a simple model to describe polyamorphism in single-component fluids using a maximum-valence approach. The model contains three types of interactions: (i) Atoms attract each other by van der Waals forces that generate a liquid-gas transition at low pressures, (ii) atoms may form covalent bonds that induce association, and (iii) atoms with maximal valence attract or repel each other stronger than other atoms, thus generating liquid-liquid separation. As an example, we qualitatively compare this model with the behavior of liquid sulfur and show that condition (iii) generates a liquid-liquid phase transition in addition to the liquid-gas phase transition.

5.
J Chem Phys ; 156(8): 084502, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35232197

RESUMO

If a binary liquid mixture, composed of two alternative species with equal amounts, is quenched from a high temperature to a low temperature, below the critical point of demixing, then the mixture will phase separate through a process known as spinodal decomposition. However, if the two alternative species are allowed to interconvert, either naturally (e.g., the equilibrium interconversion of enantiomers) or forcefully (e.g., via an external source of energy or matter), then the process of phase separation may drastically change. In this case, depending on the nature of interconversion, two phenomena could be observed: either phase amplification, the growth of one phase at the expense of another stable phase, or microphase separation, the formation of nongrowing (steady-state) microphase domains. In this work, we phenomenologically generalize the Cahn-Hilliard theory of spinodal decomposition to include the molecular interconversion of species and describe the physical properties of systems undergoing either phase amplification or microphase separation. We apply the developed phenomenology to accurately describe the simulation results of three atomistic models that demonstrate phase amplification and/or microphase separation. We also discuss the application of our approach to phase transitions in polyamorphic liquids. Finally, we describe the effects of fluctuations of the order parameter in the critical region on phase amplification and microphase separation.

6.
Nanoscale Adv ; 5(1): 208-219, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36605807

RESUMO

The physical properties of in vitro iron-reconstituted and genetically engineered human heteropolymer ferritins were investigated. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), electron energy-loss spectroscopy (EELS), and 57Fe Mössbauer spectroscopy were employed to ascertain (1) the microstructural, electronic, and micromagnetic properties of the nanosized iron cores, and (2) the effect of the H and L ferritin subunit ratios on these properties. Mössbauer spectroscopic signatures indicate that all iron within the core is in the high spin ferric state. Variable temperature Mössbauer spectroscopy for H-rich (H21/L3) and L-rich (H2/L22) ferritins reconstituted at 1000 57Fe/protein indicates superparamagnetic behavior with blocking temperatures of 19 K and 28 K, while HAADF-STEM measurements give average core diameters of (3.7 ± 0.6) nm and (5.9 ± 1.0) nm, respectively. Most significantly, H-rich proteins reveal elongated, dumbbell, and crescent-shaped cores, while L-rich proteins present spherical cores, pointing to a correlation between core shape and protein shell composition. Assuming an attempt time for spin reversal of τ 0 = 10-11 s, the Néel-Brown formula for spin-relaxation time predicts effective magnetic anisotropy energy densities of 6.83 × 104 J m-3 and 2.75 × 104 J m-3 for H-rich and L-rich proteins, respectively, due to differences in surface and shape contributions to magnetic anisotropy in the two heteropolymers. The observed differences in shape, size, and effective magnetic anisotropies of the derived biomineral cores are discussed in terms of the iron nucleation sites within the interior surface of the heteropolymer shells for H-rich and L-rich proteins. Overall, our results imply that site-directed nucleation and core growth within the protein cavity play a determinant role in the resulting core morphology. Our findings have relevance to iron biomineralization processes in nature and the growth of designer's magnetic nanoparticles within recombinant apoferritin nano-templates for nanotechnology.

7.
J Chem Phys ; 155(20): 204502, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34852466

RESUMO

Liquid-liquid phase separation of fluids exhibiting interconversion between alternative states has been proposed as an underlying mechanism for fluid polyamorphism and may be of relevance to the protein function and intracellular organization. However, molecular-level insight into the interplay between competing forces that can drive or restrict phase separation in interconverting fluids remains elusive. Here, we utilize an off-lattice model of enantiomers with tunable chiral interconversion and interaction properties to elucidate the physics underlying the stabilization and tunability of phase separation in fluids with interconverting states. We show that introducing an imbalance in the intermolecular forces between two enantiomers results in nonequilibrium, arrested phase separation into microdomains. We also find that in the equilibrium case, when all interaction forces are conservative, the growth of the phase domain is restricted only by the system size. In this case, we observe phase amplification, in which one of the two alternative phases grows at the expense of the other. These findings provide novel insights on how the interplay between dynamics and thermodynamics defines the equilibrium and steady-state morphologies of phase transitions in fluids with interconverting molecular or supramolecular states.

8.
Phys Rev E ; 103(6): L060101, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34271768

RESUMO

A fluid composed of two molecular species may undergo phase segregation via spinodal decomposition. However, if the two molecular species can interconvert, e.g., change their chirality, then a phenomenon of phase amplification, which has not been studied so far to our best knowledge, emerges. As a result, eventually, one phase will completely eliminate the other one. We model this phenomenon on an Ising system which relaxes to equilibrium through a hybrid of Kawasaki-diffusion and Glauber-interconversion dynamics. By introducing a probability of Glauber-interconversion dynamics, we show that the particle conservation law is broken, thus resulting in phase amplification. We characterize the speed of phase amplification through scaling laws based on the probability of Glauber dynamics, system size, and distance to the critical temperature of demixing.

9.
Int J Hyperthermia ; 37(1): 854-860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32664768

RESUMO

BACKGROUND: Hyperthermia (heating to 43 °C) activates the innate immune system and improves bladder cancer chemosensitivity. OBJECTIVE: To evaluate the tissue penetration and safety of convective hyperthermia combined with intravesical mitomycin C (MMC) pharmacokinetics in live porcine bladder models using the Combat bladder recirculation system (BRS). METHODS: Forty 60 kg-female swine were anesthetized and catheterized with a 3-way, 16 F catheter. The Combat device was used to heat the bladders to a target temperature of 43 °C with recirculating intravesical MMC at doses of 40, 80, and 120 mg. Dwell-heat time varied from 30-180 min. Rapid necropsy with immediate flash freezing of tissues, blood and urine occurred. MMC concentrations were measured by liquid chromatography tandem-mass spectrometry. RESULTS: The Combat BRS system was able to achieve target range temperature (42-44 °C) in 12 mins, and this temperature was maintained as long as the device was running. Two factors increased tissue penetration of MMC in the bladder: drug concentration, and the presence of heat. In the hyperthermia arm, MMC penetration saturated at 80 mg, suggesting that with heating, drug absorption may saturate and not require higher doses to achieve the maximal biological effect. Convective hyperthermia did not increase the MMC concentration in the liver, heart, kidney, spleen, lung, and lymph node tissue even at the 120 mg dose. CONCLUSIONS: Convective bladder hyperthermia using the Combat BRS device is safe and the temperature can be maintained at 43 °C. Hyperthermia therapy may increase MMC penetration into the bladder wall but does not result in an increase of MMC levels in other organs.


Assuntos
Hipertermia Induzida , Neoplasias da Bexiga Urinária , Administração Intravesical , Animais , Antibióticos Antineoplásicos/uso terapêutico , Feminino , Hipertermia , Mitomicina/uso terapêutico , Suínos , Neoplasias da Bexiga Urinária/tratamento farmacológico
10.
Angew Chem Int Ed Engl ; 59(35): 15215-15219, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32441448

RESUMO

Despite their connection to ammonia synthesis, little is known about the ability of iron-bound, bridging nitrides to form N-H bonds. Herein we report a linear diiron bridging nitride complex supported by a redox-active macrocycle. The unique ability of the ligand scaffold to adapt to the geometric preference of the bridging species was found to facilitate the formation of N-H bonds via proton-coupled electron transfer to generate a µ-amide product. The structurally analogous µ-silyl- and µ-borylamide complexes were shown to form from the net insertion of the nitride into the E-H bonds (E=B, Si). Protonation of the parent bridging amide produced ammonia in high yield, and treatment of the nitride with PhSH was found to liberate NH3 in high yield through a reaction that engages the redox-activity of the ligand during PCET.


Assuntos
Transporte de Elétrons/fisiologia , Nitrogênio/química , Ligação de Hidrogênio , Oxirredução
11.
Int. braz. j. urol ; 46(1): 42-52, Jan.-Feb. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1056364

RESUMO

ABSTRACT Introduction: Tables predicting the probability of a positive bone scan in men with non-metastatic, castrate-resistant prostate cancer have recently been reported. We performed an external validation study of these bone scan positivity tables. Materials and Methods: We performed a retrospective cohort study of patients seen at a tertiary care medical center (1996-2012) to select patients with non-metastatic, castrate-resistant prostate cancer. Abstracted data included demographic, anthropometric, and disease-specific data such as patient race, BMI, PSA kinetics, and primary treatment. Primary outcome was metastasis on bone scan. Multivariable logistic regression was performed using generalized estimating equations to adjust for repeated measures. Risk table performance was assessed using ROC curves. Results: We identified 6.509 patients with prostate cancer who had received hormonal therapy with a post-hormonal therapy PSA ≥2ng/mL, 363 of whom had non-metastatic, castrate-resistant prostate cancer. Of these, 187 patients (356 bone scans) had calculable PSA kinetics and ≥1 bone scan. Median follow-up after castrate-resistant prostate cancer diagnosis was 32 months (IQR: 19-48). There were 227 (64%) negative and 129 (36%) positive bone scans. On multivariable analysis, higher PSA at castrate-resistant prostate cancer (4.67 vs. 4.4ng/mL, OR=0.57, P=0.02), shorter time from castrate-resistant prostate cancer to scan (7.9 vs. 14.6 months, OR=0.97, P=0.006) and higher PSA at scan (OR=2.91, P <0.0001) were significantly predictive of bone scan positivity. The AUC of the previously published risk tables for predicting scan positivity was 0.72. Conclusion: Previously published risk tables predicted bone scan positivity in men with non-metastatic, castrate-resistant prostate cancer with reasonable accuracy.


Assuntos
Humanos , Masculino , Idoso , Neoplasias Ósseas/secundário , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Valores de Referência , Fatores de Tempo , Osso e Ossos/diagnóstico por imagem , Modelos Logísticos , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Curva ROC , Antígeno Prostático Específico/sangue , Medição de Risco , Gradação de Tumores , Pessoa de Meia-Idade
12.
Int Braz J Urol ; 46(1): 42-52, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31851457

RESUMO

INTRODUCTION: Tables predicting the probability of a positive bone scan in men with non-metastatic, castrate-resistant prostate cancer have recently been reported. We performed an external validation study of these bone scan positivity tables. MATERIALS AND METHODS: We performed a retrospective cohort study of patients seen at a tertiary care medical center (1996-2012) to select patients with non-metastatic, castrate-resistant prostate cancer. Abstracted data included demographic, anthropometric, and disease-specific data such as patient race, BMI, PSA kinetics, and primary treatment. Primary outcome was metastasis on bone scan. Multivariable logistic regression was performed using generalized estimating equations to adjust for repeated measures. Risk table performance was assessed using ROC curves. RESULTS: We identified 6.509 patients with prostate cancer who had received hormonal therapy with a post-hormonal therapy PSA ≥2ng/mL, 363 of whom had non-metastatic, castrate-resistant prostate cancer. Of these, 187 patients (356 bone scans) had calculable PSA kinetics and ≥1 bone scan. Median follow-up after castrate-resistant prostate cancer diagnosis was 32 months (IQR: 19-48). There were 227 (64%) negative and 129 (36%) positive bone scans. On multivariable analysis, higher PSA at castrate-resistant prostate cancer (4.67 vs. 4.4ng/mL, OR=0.57, P=0.02), shorter time from castrate-resistant prostate cancer to scan (7.9 vs. 14.6 months, OR=0.97, P=0.006) and higher PSA at scan (OR=2.91, P<0.0001) were significantly predictive of bone scan positivity. The AUC of the previously published risk tables for predicting scan positivity was 0.72. CONCLUSION: Previously published risk tables predicted bone scan positivity in men with non-metastatic, castrate-resistant prostate cancer with reasonable accuracy.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/patologia , Idoso , Osso e Ossos/diagnóstico por imagem , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Curva ROC , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
13.
Urol Clin North Am ; 47(1): 55-72, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31757301

RESUMO

Non-muscle-invasive bladder cancer can be a challenging disease to manage. In recent years, hyperthermia therapy in conjunction with intravesical therapy has been gaining traction as a treatment option for bladder cancer, especially if Bacillus Calmette-Guerin might not be available. Trials of intravesical chemotherapy with heat are few and there has been considerable heterogeneity between studies. However, multiple new trials have accrued and high-quality data are forthcoming. In this review, we discuss the role of combined intravesical hyperthermia and chemotherapy as a novel approach for the treatment of bladder cancer.


Assuntos
Hipertermia Induzida/métodos , Mitomicina/administração & dosagem , Neoplasias da Bexiga Urinária/terapia , Administração Intravesical , Antibióticos Antineoplásicos/administração & dosagem , Humanos , Resultado do Tratamento
14.
J Natl Compr Canc Netw ; 17(12): 1529-1554, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31805523

RESUMO

Testicular cancer is relatively uncommon and accounts for <1% of all male tumors. However, it is the most common solid tumor in men between the ages of 20 and 34 years, and the global incidence has been steadily rising over the past several decades. Several risk factors for testicular cancer have been identified, including personal or family history of testicular cancer and cryptorchidism. Testicular germ cell tumors (GCTs) comprise 95% of malignant tumors arising in the testes and are categorized into 2 main histologic subtypes: seminoma and nonseminoma. Although nonseminoma is the more clinically aggressive tumor subtype, 5-year survival rates exceed 70% with current treatment options, even in patients with advanced or metastatic disease. Radical inguinal orchiectomy is the primary treatment for most patients with testicular GCTs. Postorchiectomy management is dictated by stage, histology, and risk classification; treatment options for nonseminoma include surveillance, systemic therapy, and nerve-sparing retroperitoneal lymph node dissection. Although rarely occurring, prognosis for patients with brain metastases remains poor, with >50% of patients dying within 1 year of diagnosis. This selection from the NCCN Guidelines for Testicular Cancer focuses on recommendations for the management of adult patients with nonseminomatous GCTs.


Assuntos
Guias de Prática Clínica como Assunto/normas , Neoplasias Testiculares/classificação , Neoplasias Testiculares/terapia , Terapia Combinada , Humanos , Masculino , Metástase Neoplásica , Prognóstico , Neoplasias Testiculares/diagnóstico
15.
Urol Oncol ; 36(10): 469.e21-469.e29, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30126776

RESUMO

PURPOSE: A nutritious diet has been associated with better health-related quality of life (HRQOL) in a variety of cancer survivors. However, little is known about dietary habits and its association with HRQOL in bladder cancer survivors. The objective of this cross-sectional study is to describe dietary intake patterns and its relationship to HRQOL in a large cohort of bladder cancer survivors. METHODS: Bladder cancer survivors within our institutional database were mailed surveys to assess dietary intake patterns utilizing the Diet History Questionnaire II and assessing HRQOL utilizing the Functional Assessment of Cancer Therapy-Bladder Cancer. Diet quality was assessed via Healthy Eating Index 2010 scores based on subjects' Diet History Questionnaire II results. Univariate and multivariate analyses of HRQOL based on diet quality were used to evaluate whether diet quality was associated with HRQOL. RESULTS: Four hundred and fifty-nine patients (48%) returned questionnaires. Mean age was 74 years, 81% were male and 28% underwent radical cystectomy. Diet quality and quantity in our cohort was similar to the general older U.S. population and did not differ significantly between those managed conservatively or long-term following cystectomy. Our cohort had low intake of whole grains and fat-soluble vitamins, particularly vitamin D. Diet quality was significantly associated with HRQOL in the univariate analysis but lost statistical significance in our multivariate analysis. Elixhauser Comorbidity Index was significantly associated with HRQOL in the multivariate analysis. CONCLUSIONS: This study demonstrates a similar diet quality of bladder cancer survivors to the older general U.S. population that, on average, "needs improvement." Dietary intake is particularly lacking in whole grain and vitamin D intake. Future studies are warranted to determine the impact on long-term outcome, but bladder cancer survivors should be counseled on the importance and benefits of adherence to dietary guidelines, including its potential contribution toward better HRQOL.


Assuntos
Sobreviventes de Câncer , Dieta , Qualidade de Vida , Neoplasias da Bexiga Urinária , Adulto , Idoso , Estudos Transversais , Inquéritos sobre Dietas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Can J Urol ; 24(5): 8982-8989, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28971784

RESUMO

INTRODUCTION: Contemporary clinical guidelines utilize the highest Gleason sum (HGS) in any one core on prostate biopsy to determine prostate cancer treatment. Here, we present a large discrepancy between prostate cancer risk stratified as high risk on biopsy and their pathology after radical prostatectomy. MATERIALS AND METHODS: We retrospectively reviewed 1424 men who underwent either open or robotic-assisted prostatectomy between 2004 and 2015. We analyzed 148 men who were diagnosed with HGS 8 on prostate biopsy. Biopsy and prostatectomy pathology were compared in aggregate and over 1 year time intervals. Chi-squared test, Fisher's exact test, Student's t-test, and Wilcoxon Rank-Sum test were used for statistical analysis. RESULTS: A total of 61.5% (91/148) of clinical HGS 8 diagnoses were downgraded on prostatectomy, with 58.8% (87/148) downgraded to Gleason 7 (Gleason 4 + 3 n = 59; Gleason 3 + 4 n = 28). Factors associated with downgrading include lower prostate-specific antigen (PSA) at biopsy (median 6.8 ng/mL versus 9.1 ng/mL, p < 0.001), number of Gleason 8 biopsy cores (median 1 versus 2, p < 0.02), presence of Gleason pattern 3 on biopsy cores (67.9% versus 44.8%, p < 0.03), pT2 staging (72.4% versus 55.1%, p < 0.04), positive margins (53.9% versus 69.1%, p < 0.04), extracapsular extension (53.4% versus 74.1%, p < 0.02), and smaller percent tumor (median 10% versus 15%, p < 0.004). CONCLUSION: The large percentage of pathology downgrading of biopsy-diagnosed HGS 8 suggests suboptimal risk-stratification that may lead to suboptimal treatment strategies and much patient distress. Our study adds great urgency to the efforts refining prostate cancer clinical assessment.


Assuntos
Próstata/patologia , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Período Pós-Operatório , Período Pré-Operatório , Estudos Retrospectivos , Medição de Risco
17.
Urol Oncol ; 35(9): 540.e1-540.e6, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28527621

RESUMO

INTRODUCTION: Physical activity has been shown to significantly improve health-related quality of life (HRQOL) and survivorship in a variety of patients with cancer . However, little is known about the physical activity patterns of bladder cancer survivors and how these are related to HRQOL in the United States. Our objective was to describe self-reported physical activity patterns and HRQOL and examine the association between these measures in a large cohort of bladder cancer survivors. MATERIAL AND METHODS: In this cross-sectional study, long-term bladder cancer survivors identified through an institutional database were mailed a survey that included the Functional Assessment of Cancer Therapy Bladder Cancer (FACT-BL) and the International Physical Activity Questionnaire (IPAQ). Associations between HRQOL, as assessed by the FACT-BL, and physical activity, as assessed by the IPAQ, were examined by stratified analyses of HRQOL by different levels of physical activity, proportional odds ordinal logistic regression models, and local polynomial regression models. RESULTS: A total of 472 subjects (49% response rate) completed the survey. The mean age was 74 years; 81% were male and 87% were white. The median total weekly physical activity was 2,794 MET-min. Subjects reporting "high" physical activity had a median FACT-BL score of 129 compared with 119 among those reporting "low" physical activity, a statistically and clinically significant difference. Similarly, subjects reporting "high" physical activity had a 2.2-fold increased odds of reporting higher global HRQOL compared with subjects reporting "low" physical activity. CONCLUSIONS: This large cohort of bladder cancer survivors reported high levels of physical activity. Physical activity was positively associated with HRQOL. Further studies investigating the causal relationship between physical activity and HRQOL in the posttreatment setting in bladder cancer survivors are warranted.


Assuntos
Exercício Físico/fisiologia , Qualidade de Vida/psicologia , Neoplasias da Bexiga Urinária/psicologia , Idoso , Feminino , Humanos , Masculino , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/terapia
18.
Urol Oncol ; 35(7): 459.e1-459.e5, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28284892

RESUMO

OBJECTIVES: To investigate the potential association between body mass index (BMI) and clinicopathological features of clinically localized renal masses. MATERIALS AND METHODS: An international, multi-institutional retrospective review of patients who underwent surgery for clinically localized renal masses between 2000 and 2010 was undertaken after an institutional review board approval. Patients were divided into 4 absolute BMI groups based on the entire cohort׳s percentiles and 4 relative BMI groups based on their respective population (American or Italian). Renal mass pathological diagnosis, renal cell carcinoma (RCC) subtype, Fuhrman grade (low and high), and clinical stage were compared among groups using Fisher׳s exact test, Kruskal-Wallis test, and the Cochran-Armitage trend test. A multivariate logistic analysis was performed to evaluate independent association between tumor and patient characteristics with tumor pathology (Fuhrman grade). RESULTS: A total of 1,748 patients having a median BMI of 28 (interquartile range 25-32) were evaluated. Benign masses and RCC cases had similar proportion across BMI groups (P = 0.4). The most common RCC subtype was clear cell followed by papillary carcinoma, chromophobe, and other subtypes. Their distribution was comparable across BMI groups (P = 0.7). Similarly, clinical stage distribution was comparable with the overall cohort. The distribution of Fuhrman grade in RCC, however, demonstrated an increased proportions of low grade with increasing BMI (P<0.05). This trend was maintained in subgroups according to gender, stage and age (P<0.05 in all subgroup analysis). In a multivariable model that included potential confounders (i.e., age, sex, and tumor size) higher BMI groups had lower odds of presenting a high Fuhrman grade. CONCLUSION: In this study, higher BMI was associated with lower grade of RCC in clinically localized renal masses. This may, in part, explain better survival rates in patients with higher BMI and may correlate with a possible link between adipose tissue and RCC biology.


Assuntos
Índice de Massa Corporal , Idoso , Carcinoma de Células Renais/patologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Cancer Biomark ; 18(4): 381-387, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28106542

RESUMO

BACKGROUND: Abnormal methylation of urinary TWIST1 and NID2 conferred high sensitivity and specificity for the detection of urothelial carcinoma. OBJECTIVE: We examine the performance of the urine-based TWIST1/NID2 methylation assay with the addition of urine cytology for the detection of urothelial carcinoma. MATERIALS AND METHODS: A prospective multi-institutional study was conducted to assess the performance of a methylation assay for patients with hematuria or under surveillance for non-muscle invasive bladder cancer (NMIBC). All patients underwent cystoscopy, a methylation assay, and cytology. Receiver operator characteristic (ROC) curves were constructed for cytology alone, the methylation assay alone, and a combined model. Areas under the curve (AUC) were compared using likelihood ratio tests. RESULTS: A total of 172 patients were enrolled (37% for hematuria and 63% NMIBC). The AUC for cytology alone with equivocal cytologies positive was 0.704, and improved to 0.773 with the addition of the DNA methylation assay (p < 0.001). When the equivocal cytologies were considered negative, the AUC improved from 0.558 to 0.697 with the addition of the DNA methylation assay (p = 0.003). CONCLUSIONS: Addition of a TWIST1/NID2-based DNA methylation assay adds diagnostic value to urine cytology and the model is sensitive to the classification of equivocal cytology.


Assuntos
Carcinoma de Células de Transição/urina , Moléculas de Adesão Celular/urina , Proteínas Nucleares/urina , Proteína 1 Relacionada a Twist/urina , Neoplasias da Bexiga Urinária/urina , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/urina , Proteínas de Ligação ao Cálcio , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , Moléculas de Adesão Celular/genética , Cistoscopia , Metilação de DNA/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Proteína 1 Relacionada a Twist/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
20.
Ann Surg Oncol ; 24(6): 1747-1753, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28074325

RESUMO

PURPOSE: The aim of this study was to establish the criteria defining an anticipatory positive test for bladder cancer. METHODS: We reviewed all patients at our institution who underwent urine cytology or UroVysion fluorescence in situ hybridization (FISH) and cystoscopy from 2003 to 2012. Test performance and cancer anticipation was assessed using generalized linear mixed models, mixed-effects proportional hazards models, and cumulative incidence curves using tests performed within 30 days of each other as well as within a lag time of 1 year. RESULTS: Overall, 6729 urine tests (4729 cytology and 2040 UroVysion FISH) were paired with gold-standard cystoscopies. Sensitivity and specificity were 63 and 41% for cytology, and 37 and 84% for UroVysion FISH, respectively. A 1-year lag time allowed for cancer anticipation and neither test improved. Among patients with positive cytology and initially negative cystoscopy, the hazard ratio of developing a bladder tumor at 1 year was 1.83; 76% of these patients developed a tumor within 1 year. Similarly, among patients with a positive FISH and initially negative cystoscopy, the hazard ratio of developing a bladder tumor at 1 year was 1.56; 40% of these patients developed a tumor within 1 year. CONCLUSIONS: Urine-based tests for bladder cancer are frequently falsely positive. With further follow-up time, some of these false positive tests are vindicated as true (anticipatory) positive tests, although many will remain false positives. We developed statistical criteria to determine if a test anticipates future cancers or not.


Assuntos
Cistoscopia/métodos , Citodiagnóstico , Hibridização in Situ Fluorescente/métodos , Urinálise/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/urina
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