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1.
J Pediatr Urol ; 20(4): 682-687, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38710598

RESUMO

BACKGROUND: Hypospadias phenotype assessment determines if the anatomy is favorable for reconstruction. Glans-Urethral Meatus-Shaft (GMS) has been adopted in an effort to standardize hypospadias classification. While extremely subjective, GMS has been widely used to classify the severity of the phenotype to predict surgical outcomes. The use of digital image analysis has proven to be feasible and prior efforts by our team have demonstrated that machine learning algorithms can emulate an expert's assessment of the phenotype. Nonetheless, the creation of these image recognition algorithms is highly subjective. In order to reduce a subjective input in the evaluation of the phenotype, we propose a novel approach to analyze the anatomy using digital image pixel analysis and to compare the results using the GMS score. Our hypothesis is that pixel cluster segmentation can discriminate between favorable and unfavorable anatomy. OBJECTIVE: To evaluate whether image segmentation and digital pixel analysis are able to analyze favorable vs unfavorable hypospadias anatomy in a less subjective manner than GMS score. METHODS: A total of 148 patients with different types of hypospadias were classified by 1 of 5 independent experts following the GMS score into "favorable" (GG), "moderately favorable" (GM) and "unfavorable" (GP) glans. From there, 592 images were generated using digital image segmentation. 584 were included for final analysis due to certain images being excluded for poor image quality or inadequate capture of target anatomy. For each image, the region of interest was segmented separately by two evaluators into "glans," "urethral plate," "foreskin" and "periurethral plate". The values obtained for each segmented region using machine-learning statistical pixel k-means cluster analysis were analyzed and compared to the GMS score given to that image using an ANOVA analysis. RESULTS: Analysis of image segmentation demonstrated that k-means pixel cluster analysis discriminated "favorable" vs "unfavorable" urethral plates. There was a significant difference between scores when comparing the GG and GM groups (p = 0.03) and GG and GP groups (p = 0.05). Pixel cluster analysis could not discriminate between "moderately favorable" and "unfavorable" urethral plates. CONCLUSIONS: Through our analysis, we found significant pairwise difference for different tissue qualities. Digital image segmentation and statistical k-means cluster analysis can discriminate anatomical features in a similar way to the GMS score. Future research can target discerning between different tissue qualities in an effort to predict surgical outcomes for hypospadias repair.


Assuntos
Hipospadia , Fenótipo , Uretra , Hipospadia/cirurgia , Hipospadia/diagnóstico por imagem , Humanos , Masculino , Uretra/diagnóstico por imagem , Uretra/cirurgia , Pênis/cirurgia , Pênis/diagnóstico por imagem , Pênis/anormalidades , Lactente , Pré-Escolar , Aprendizado de Máquina , Estudos Retrospectivos , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Processamento de Imagem Assistida por Computador/métodos
2.
Urol Oncol ; 39(7): 435.e23-435.e31, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33397594

RESUMO

BACKGROUND: Prior studies have demonstrated declines in androgen levels in men with cancer and patients undergoing anesthesia and surgery. In this study, we hypothesized that decreased serum androgen levels are prevalent in male patients undergoing radical cystectomy (RC) for bladder cancer and that it persists in the postoperative period. We characterized perioperative androgen hormonal profiles and examined for associated changes indicative of sarcopenia on computed tomography scans in men undergoing RC. METHODS: We implemented a prospective observational trial in men with newly diagnosed non-metastatic bladder cancer undergoing RC. Baseline pre-operative total testosterone (TT), free testosterone (FT), and luteinizing hormone (LH) were obtained on morning lab draws with 30 days of surgery. TT and FT were then repeated on postoperative days (POD) 2, 3, 30, and 90. The threshold for normal TT was defined as >300 ng/dl, consistent with the AUA Guidelines for Evaluation and Management of Testosterone Deficiency. We evaluated postoperative changes in weight and psoas muscle cross-sectional area using computed tomography scans to assess for sarcopenic changes. RESULTS: Univariable statistical analysis was performed. 25 patients were enrolled. The mean patient age was 68.9 years. The mean pre-operative TT was 308 ng/dl, and 12/23 (52.5%) patients had low testosterone. Mean TT onPOD 2 and 3 were 166 ng/dl and 161 ng/dl, respectively (range 24-345). 19/20 (95%) of men who had morning lab draws had decreased TT. The mean TT at 30 days was 253 ng/dl with 37.5% of men having low TT. Mean TT at 90 days was 306 ng/dl. The mean FT levels were 43 ng/dl, 29.25 ng/dl, 28.2 ng/dl, 40.89 ng/dl, and 42.62 ng/dl at baseline, POD 2, POD 3, POD 30, and POD 90, respectively. Mean LH at baseline was 9.9 IU/L. Average weight loss at 30- and 90- days postop was -4.29 and -4.38 kilograms, respectively. Weight loss was persistent with only 3/23 (13%) returning to their presurgery weight by 90 days. Despite significant declines in weight and perioperative TT, no significant differences in psoas muscle cross-sectional area were observed (net change -92 mm2, P= 0.13) CONCLUSIONS: Perioperative disruption of androgen levels is prevalent in men undergoing RC. Our trial demonstrates a pre-op, immediate postop, 30- and 90-day postoperative prevalence of low TT of 52%, 95%, 63%, and 37.5%, respectively. Significant changes in baseline weight were noted, although no significant changes in psoas muscle cross-sectional area were observed, limiting conclusions regarding a link between changes in androgens and sarcopenia in this setting.


Assuntos
Cistectomia , Hormônio Luteinizante/sangue , Testosterona/sangue , Neoplasias da Bexiga Urinária/sangue , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistectomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Período Perioperatório , Estudos Prospectivos
3.
Cancer Epidemiol Biomarkers Prev ; 29(6): 1229-1236, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32277004

RESUMO

BACKGROUND: The association between male pattern baldness and prostate cancer has been inconsistent. We prospectively investigated the association between baldness at age 45 and prostate cancer risk in the Health Professionals Follow-up Study (HPFS), focusing on clinical and molecular markers. METHODS: Baldness was self-reported on the 1992 questionnaire using the modified Norwood-Hamilton scale prior to diagnosis. We estimated HRs between baldness and prostate cancer risk among 36,760 men, with follow-up through 2014. We also investigated whether baldness was associated with prostate cancer defined by tumor protein expression of androgen receptor and the presence of the TMPRSS2:ERG fusion. RESULTS: During 22 years, 5,157 prostate cancer cases were identified. Fifty-six percent of the men had either frontal or vertex baldness. No significant associations were found between baldness and prostate cancer risk. Among men younger than 60 years, there was a statistically significant association between frontal and severe vertex baldness and overall prostate cancer (HR: 1.74; 95% confidence interval: 1.23-2.48). Baldness was not significantly associated with expression of molecular subtypes defined by AR and TMPRSS2:ERG IHC of prostate tumors. CONCLUSIONS: This study showed no association between baldness at age 45 and prostate cancer risk, overall or for clinical or molecular markers. The association between baldness and overall prostate cancer among younger men is intriguing, but caution is warranted when interpreting this finding. IMPACT: The null findings from this large cohort study, together with previous literature's inconclusive findings across baldness patterns, suggest that baldness is not a consistent biomarker for prostate cancer risk or progression.


Assuntos
Alopecia/complicações , Neoplasias da Próstata/fisiopatologia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
J Pain Symptom Manage ; 59(3): 590-598, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31655192

RESUMO

CONTEXT: Patients with decompensated cirrhosis have high rates of health care utilization at end of life (EOL). However, the impact of transplant candidacy on intensity of EOL care is currently unknown. OBJECTIVES: To assess the relationship between transplant candidacy and intensity of EOL care in the last year of life in an ambulatory cohort of patients with decompensated cirrhosis. METHODS: We performed a retrospective analysis of 230 patients with decompensated cirrhosis who were evaluated for liver transplantation in a large health care system between 1/1/2010 and 12/31/2017 and died by 6/20/2018. We compared health care utilization in the last year of life and EOL care outcomes between transplant-listed (n = 133) and nonlisted (n = 97) patients. We examined predictors of palliative and hospice care utilization using multivariate logistic regression. RESULTS: During the last year of life, patients had a median of three hospitalizations (IQR 2-5) and spent a median of 31 days (IQR 16-49) in the hospital. In all, 80% of patients died in the hospital, with 70% dying in the intensive care unit. The majority (70.0%) received a life-sustaining procedure (mechanical ventilation, renal replacement therapy, or cardiopulmonary resuscitation) during their terminal hospitalization, which did not differ between transplant-listed and nonlisted patients (74.4% vs. 63.9%, P = 0.09). Transplant-listed patients had lower odds of receiving specialty palliative care (odds ratio 0.43, P = 0.005). Patients with hepatocellular carcinoma had higher odds of receiving hospice care (odds ratio 2.03, P = 0.049). CONCLUSION: Patients with decompensated cirrhosis had intensive health care utilization during their last year of life regardless of transplant candidacy. Further work is needed to optimize their EOL care, particularly for patients who are ineligible for transplantation.


Assuntos
Carcinoma Hepatocelular , Doença Hepática Terminal , Varizes Esofágicas e Gástricas , Cuidados Paliativos na Terminalidade da Vida , Neoplasias Hepáticas , Assistência Terminal , Feminino , Hemorragia Gastrointestinal , Humanos , Cirrose Hepática/terapia , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Retrospectivos , Índice de Gravidade de Doença
5.
Nano Lett ; 19(2): 948-957, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30582700

RESUMO

Polaritonic materials that support epsilon-near-zero (ENZ) modes offer the opportunity to design light-matter interactions at the nanoscale through extreme subwavelength light confinement, producing phenomena like resonant perfect absorption. However, the utility of ENZ modes in nanophotonic applications has been limited by a flat spectral dispersion, which leads to small group velocities and extremely short propagation lengths. Here, we overcome this constraint by hybridizing ENZ and surface plasmon polariton (SPP) modes in doped cadmium oxide epitaxial bilayers. This results in strongly coupled hybrid modes that are characterized by an anticrossing in the polariton dispersion and a large spectral splitting on the order of 1/3 of the mode frequency. These hybrid modes simultaneously achieve modal propagation and ENZ mode-like interior field confinement, adding propagation character to ENZ mode properties. We subsequently tune the resonant frequencies, dispersion, and coupling of these polaritonic-hybrid-epsilon-near-zero (PH-ENZ) modes by tailoring the modal oscillator strength and the ENZ-SPP spectral overlap. PH-ENZ modes ultimately leverage the most desirable characteristics of both ENZ and SPP modes, allowing us to overcome the canonical plasmonic trade-off between confinement and propagation length.

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