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1.
Retina ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151183

RESUMO

PURPOSE: To evaluate high-risk histopathological features (HRHF) following primary enucleation of eyes with retinoblastoma (RB) and assess the patient outcomes across continents. METHODS: Retrospective study of 1426 primarily enucleated RB eyes from five continents. RESULTS: Of all, 923 (65%) were from Asia (AS), 27 (2%) from Australia (AUS), 120 (8%) from Europe (EUR), 162 (11%) from North America (NA), and 194 (14%) from South America (SA). Based on the continent (AS vs. AUS vs. EUR vs. NA vs. SA), the histopathology features included massive choroidal invasion (31% vs. 7% vs. 13% vs. 19% vs. 27%, p=0.001), post-laminar optic nerve invasion (27% vs. 0% vs. 16% vs. 21% vs. 19%, p=0.0006), scleral infiltration (5% vs. 0% vs. 4% vs. 2% vs. 7%, p=0.13), and microscopic extrascleral infiltration (4% vs. 0% vs. <1% vs. <1% vs. 4%, p=0.68). Adjuvant chemotherapy with/without orbital radiotherapy was given in 761 (53%) patients. Based on Kaplan-Meier estimates in different continents (AS vs. AUS vs. EUR vs. NA vs. SA), the 6-year risk of orbital tumor recurrence was 5% vs. 2% vs. 0% vs. 0% vs. 12% (p<0.001), systemic metastasis was reported in 8% vs. 5% vs. 2% vs. 0% vs. 13% (p=0.001), and death in 10% vs. 3% vs. 2% vs. 0% vs. 11% (p<0.001) patients. CONCLUSION: There is a wide variation in the infiltrative histopathology features of RB across continents, resulting in variable outcomes. SA and AS had a higher risk of orbital tumor recurrence, systemic metastasis, and death compared to AUS, EUR, and NA.

2.
Prostate ; 83(9): 823-830, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36938936

RESUMO

BACKGROUND: Androgens are generally thought to cause prostate cancer, but the data from animal studies suggest that they must be aromatized to estrogen and act in concert with genotoxic estrogen metabolites. The objective of this study was to determine whether treatment with testosterone (T) combined with a nonestrogenic estrogen metabolite and a nongenotoxic estrogenic compound would all be necessary and sufficient for the induction of a high incidence of prostate cancer in the susceptible NBL rat strain. METHODS: NBL rats were treated with low-dose testosterone via slow-release Silastic implants and with the marginally estrogenic genotoxic catechol estrogen 4-hydroxyestradiol (4OH-E2) and the nongenotoxic estrogen 2-fluoroestradiol (2F-E2) and in one experiment the aromatase inhibitor letrozole via custom-made slow-release pellets. Animals were euthanized 52 weeks after implantation and their pituitaries and prostate complexes weighed and fixed in formalin. Hematoxylin and eosin (H&E)-stained step sections were prepared and examined microscopically for proliferative lesions. RESULTS: Animals treated with 2F-E2, with or without the other compounds, had enlarged pituitaries demonstrating its estrogenicity. Animals treated with T, with or without the other compounds, had enlarged prostates consistent with its androgenicity. Rats treated with T plus 2F-E2 and 4OH-E2 developed a high incidence of prostatic cancer (89%), while, surprisingly, rats treated with T plus only 2F-E2 also had a high incidence of prostate cancer (95%) contradicting our initial hypothesis. To test whether the formation of E2 from T by aromatase could lead to estrogen genotoxicity and prostate carcinogenesis we then rats treated with T and 2F-E2 also with letrozole and found that it reduced prostate cancer incidence by about 50%. CONCLUSIONS: These findings indicate that long-term treatment with a nongenotoxic estrogen (2F-E2) and T as well as uninhibited prostatic aromatase activity generating genotoxic E2 are all required for induction of a high incidence of prostatic adenocarcinomas in NBL rats. These and previous data indicate that androgen receptor-mediated action, estrogen receptor mediation, and estrogen genotoxicity are all required and sufficient for hormonal carcinogenesis in the NBL rat prostate. Interference with the estrogen genotoxicity is a potential approach to prostate cancer chemoprevention.


Assuntos
Androgênios , Neoplasias da Próstata , Masculino , Humanos , Ratos , Animais , Androgênios/metabolismo , Próstata/patologia , Estradiol/metabolismo , Aromatase/genética , Aromatase/metabolismo , Letrozol/toxicidade , Letrozol/metabolismo , Estrogênios/farmacologia , Neoplasias da Próstata/patologia , Testosterona/farmacologia , Testosterona/metabolismo , Carcinogênese/patologia , Dano ao DNA
3.
JMIR Form Res ; 6(6): e32577, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35737455

RESUMO

BACKGROUND: There is growing evidence supporting the use of mobile health (mHealth) interventions in low- and middle-income countries to address resource limitations in the delivery of health information and services to vulnerable populations. In parallel, there is an increasing emphasis on the use of implementation science tools and frameworks for the early identification of implementation barriers and to improve the acceptability, appropriateness, and adoption of mHealth interventions in resource-limited settings. However, there are limited examples of the application of implementation science tools and frameworks to the formative phase of mHealth design for resource-limited settings despite the potential benefits of this work for enhancing subsequent implementation, scale-up, and sustainability. OBJECTIVE: We presented a case study on the use of an implementation science framework in mHealth design. In particular, we illustrated the usability of the Consolidated Framework for Implementation Research (CFIR) for organizing and interpreting formative research findings during the design of the mobile Inspección Visual con Ácido Acético (mIVAA) system in Lima, Peru. METHODS: We collected formative data from prospective users of the mIVAA intervention using multiple research methodologies, including structured observations, surveys, group and individual interviews, and discussions with local stakeholders at the partnering organization in Peru. These activities enabled the documentation of clinical workflows, perceived barriers to and facilitators of mIVAA, overarching barriers to cervical cancer screening in community-based settings, and related local policies and guidelines in health care. Using a convergent mixed methods analytic approach and the CFIR as an organizing framework, we mapped formative research findings to identify key implementation barriers and inform iterations of the mIVAA system design. RESULTS: In the setting of our case study, most implementation barriers were identified in the CFIR domains of intervention characteristics and inner setting. All but one barrier were addressed before mIVAA deployment by modifying the system design and adding supportive resources. Solutions involved improvements to infrastructure, including cellular data plans to avoid disruption from internet failure; improved process and flow, including an updated software interface; and better user role definition for image capture to be consistent with local health care laws. CONCLUSIONS: The CFIR can serve as a comprehensive framework for organizing formative research data and identifying key implementation barriers during mHealth intervention design. In our case study of the mIVAA system in Peru, formative research contributing to the CFIR domains of intervention characteristics and inner setting elicited the most key barriers to implementation. The early identification of barriers enabled design iterations before system deployment. Future efforts to develop mHealth interventions for low- and middle-income countries may benefit from using the approach presented in this case study as well as prioritizing the CFIR domains of intervention characteristics and inner setting.

4.
Pain Med ; 21(2): 274-290, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503275

RESUMO

OBJECTIVE: Treating chronic low back pain (CLBP) with spine-focused interventions is common, potentially dangerous, and often ineffective. This preliminary trial tests the feasibility and efficacy of caring for CLBP in older adults as a geriatric syndrome in Aging Back Clinics (ABC). DESIGN: Randomized controlled trial. SETTING: Outpatient clinics of two VA Medical Centers. SUBJECTS: Fifty-five English-speaking veterans aged 60-89 with CLBP and no red flags for serious underlying illness, prior back surgery, dementia, impaired communication, or uncontrolled psychiatric illness. METHODS: Participants were randomized to ABC care or usual care (UC) and followed for six months. ABC care included 1) a structured history and physical examination to identify pain contributors, 2) structured participant education, 3) collaborative decision-making, and 4) care guided by condition-specific algorithms. Primary outcomes were low back pain severity (0-10 current and seven-day average/worst pain) and pain-related disability (Roland Morris). Secondary outcomes included the SF-12 and health care utilization. RESULTS: ABC participants experienced significantly greater reduction in seven-day average (-1.22 points, P = 0.023) and worst pain (-1.70 points, P = 0.003) and SF-12 interference with social activities (50.0 vs 11.5%, P = 0.0030) at six months. ABC participants were less likely to take muscle relaxants (16.7 vs 42.3%, P = 0.0481). Descriptively, UC participants were more likely to experience pain-related emergency room visits (45.8% vs 30.8%) and to be exposed to non-COX2 nonsteroidal anti-inflammatory drugs (73.1% vs 54.2%). CONCLUSIONS: These preliminary data suggest that ABC care for older veterans with CLBP is feasible and may reduce pain and exposure to other potential morbidity.


Assuntos
Algoritmos , Dor Lombar/terapia , Manejo da Dor/métodos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Dor Crônica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto/métodos , Projetos Piloto , Resultado do Tratamento , Veteranos
5.
Horm Cancer ; 10(2-3): 77-88, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30877616

RESUMO

Androgens are thought to cause prostate cancer, but the underlying mechanisms are unclear. Data from animal studies suggest that for androgens to cause prostate cancer, they must be aromatized to estrogen and act in concert with estrogen metabolites. We tested the hypothesis that androgen-receptor and estrogen receptor-mediated effects of androgen and estrogen are necessary, as well as genotoxicity of estrogen metabolites. NBL rats were treated with androgenic and estrogenic compounds for 16-75 weeks through slow-release silastic implants or pellets. Testosterone alone induced cancer in the prostate of 37% of rats. 5α-Dihydrotestosterone, which cannot be converted to estradiol or testosterone, did not cause a significant prostate cancer incidence (4%). Addition of estradiol to 5α-dihydrotestosterone treatment did not markedly enhance prostate cancer incidence (14%), unlike adding estradiol to testosterone treatment which induced a 100% tumor incidence. Testosterone plus estradiol treatment induced a DNA adduct detectable by 32P-postlabeling, oxidative DNA damage (8-hydroxyguanosine), and lipid peroxidation at the site within the prostate where this treatment causes cancers, preceding later cancer formation. The non-estrogenic 4-hydroxy metabolite of estradiol, when combined with testosterone, induced prostatic dysplasia within 16 weeks and, after long-term treatment, a very low incidence of prostate cancer (21%). When an estrogen that cannot be hydroxylated (2-fluoroestradiol) was added to this combined treatment with testosterone and 4-hydroxyestradiol, dysplasia frequency after 16 weeks was doubled. These results strongly support the hypothesis, but additional definitive studies are needed which may identify new targets to interfere with these mechanisms that are clinically feasible in humans.


Assuntos
Androgênios/efeitos adversos , Carcinogênese , Estrogênios/efeitos adversos , Neoplasias da Próstata/induzido quimicamente , Animais , Carcinoma , Adutos de DNA , Dano ao DNA , Di-Hidrotestosterona/metabolismo , Estradiol/metabolismo , Estrogênios de Catecol/química , Guanosina/análogos & derivados , Guanosina/farmacologia , Humanos , Incidência , Masculino , Próstata , Ratos , Receptores de Estrogênio/metabolismo , Testosterona/metabolismo
6.
Pain Med ; 20(7): 1300-1310, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29672748

RESUMO

OBJECTIVE: To describe key peripheral and central nervous system (CNS) conditions in a group of older adults with chronic low back pain (CLBP) and their association with pain severity and self-reported and performance-based physical function. DESIGN: Cross-sectional. SETTING: Outpatient VA clinics. SUBJECTS: Forty-seven community-dwelling veterans with CLBP (age 68.0 ± 6.5 years, range = 60-88 years, 12.8% female, 66% white) participated. METHODS: Data were collected on peripheral pain generators-body mass index, American College of Rheumatology hip osteoarthritis criteria, neurogenic claudication (i.e., spinal stenosis), sacroiliac joint (SIJ) pain, myofascial pain, leg length discrepancy (LLD), and iliotibial band pain; and CNS pain generators-anxiety (GAD-7), depression (PHQ-9), insomnia (Insomnia Severity Index), maladaptive coping (Fear Avoidance Beliefs Questionnaire, Cognitive Strategies Questionnaire), and fibromyalgia (fibromyalgia survey). Outcomes were pain severity (0 to 10 scale, seven-day average and worst), self-reported pain interference (Roland Morris [RM] questionnaire), and gait speed. RESULTS: Approximately 96% had at least one peripheral CLBP contributor, 83% had at least one CNS contributor, and 80.9% had both peripheral and CNS contributors. Of the peripheral conditions, only SIJ pain and LLD were associated with outcomes. All of the CNS conditions and SIJ pain were related to RM score. Only depression/anxiety and LLD were associated with gait speed. CONCLUSIONS: In this sample of older veterans, CLBP was a multifaceted condition. Both CNS and peripheral conditions were associated with self-reported and performance-based function. Additional investigation is required to determine the impact of treating these conditions on patient outcomes and health care utilization.


Assuntos
Doenças do Sistema Nervoso Central/complicações , Avaliação da Deficiência , Dor Lombar/etiologia , Dor Lombar/psicologia , Doenças Musculoesqueléticas/complicações , Idoso , Idoso de 80 Anos ou mais , Doenças do Sistema Nervoso Central/epidemiologia , Dor Crônica , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/epidemiologia , Psicologia
7.
Environ Health Perspect ; 116(6): 703-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18560523

RESUMO

BACKGROUND: Hairless mice that ingested arsenite in drinking water exhibited more than a 5-fold enhancement of ultraviolet radiation (UVR) carcinogenesis, whereas arsenite alone was carcinogenically inactive. Dietary organoselenium blocked the cancer enhancement effect of arsenic but not cancer induction by UVR. OBJECTIVE: In this study we sought to explain selenium blockage of As enhancement by establishing the extent that As and Se tissue distributions are coincident or divergent. METHODS: We used the X-ray fluorescence microprobe at the Advanced Photon Source (Argonne National Laboratory) to probe sections of skin and liver from hairless mice exposed to a) UVR, b) UVR + As, c) UVR + organoselenium, or d) UVR + As + organoselenium. RESULTS: We found elevated levels of As in the skin epithelium (hair follicles and epidermis) and diffusely in the liver of mice exposed to UVR + As. Arsenic was entirely absent in skin in mice exposed to UVR + As + organoselenium, but a diffuse low level was seen in the liver. As and Se locations were consistently divergent in skin; As was more diffusely distributed, whereas Se was strongly associated with membranes. X-ray absorption near-edge spectra are consistent with the presence of the seleno-bis(S-glutathionyl) arsinium ion in the liver. CONCLUSIONS: Supplemental Se was uncommonly effective at preventing even a trace of As in skin at 14 or 196 days of continuous exposure to As in drinking water. Traces of the seleno-bis(S-glutathionyl) arsinium ion in the liver suggested that formation of this compound was more likely to be responsible for the As-blocking effect of Se than was a mechanism based on antioxidation.


Assuntos
Arsênio/toxicidade , Selênio/farmacologia , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos , Animais , Antineoplásicos/farmacologia , Camundongos , Camundongos Pelados , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/patologia , Neoplasias Induzidas por Radiação/prevenção & controle , Compostos Organosselênicos/farmacologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologia , Espectrometria por Raios X
8.
Prostate ; 68(7): 728-39, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18302197

RESUMO

BACKGROUND: Chronic inflammation may contribute to the development of prostate cancer. The goal of this study was to determine the possible association of prostatic inflammation, prostatic intraepithelial neoplasia (PIN)-like lesion, and prostate cancer, and to assess the androgen and estrogen dependency of the early steps of carcinogenesis. METHODS: Noble rats were treated with testosterone and estradiol implants for 13, 18, or 26 weeks. Hormone dependency of the lesions was studied in a subset of animals by removing hormone implants for 3 weeks after 15 weeks treatment time. RESULTS: After treatment for 13 weeks, acute and chronic inflammation was found in the dorsolateral prostate lobes and both inflammation and PIN-like lesions were present in the periurethal area of the prostate in all animals (n = 8). Following hormone exposure for 18 and 26 weeks, inflammation in the prostate remained, and adenocarcinomas in the periurethal prostate area with no adjacent inflammation were observed in all 18 animals studied. When both hormone implants were removed after 15 weeks, PIN-like lesions progressed further to adenocarcinoma only in two of seven animals. When only the estradiol implants were removed, three of five animals developed adenocarcinomas. CONCLUSIONS: Even though adenocarcinomas were not morphologically associated with inflammation, PIN-like lesions preceding adenocarcinoma were found in close association with inflammation, pointing towards a possible initiator role of inflammation in the early steps of prostatic carcinogenesis. Further, these results indicate that both androgens and estrogens together play a significant role in the induction of inflammation and prostatic cancer in this model.


Assuntos
Carcinoma Ductal/patologia , Lesões Pré-Cancerosas/patologia , Próstata/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Prostatite/patologia , Animais , Biomarcadores Tumorais/análise , Carcinoma Ductal/química , Carcinoma Ductal/etiologia , Modelos Animais de Doenças , Implantes de Medicamento , Estradiol/sangue , Estradiol/farmacologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Lesões Pré-Cancerosas/química , Lesões Pré-Cancerosas/etiologia , Prolactina/sangue , Próstata/efeitos dos fármacos , Neoplasia Prostática Intraepitelial/química , Neoplasia Prostática Intraepitelial/etiologia , Neoplasias da Próstata/química , Neoplasias da Próstata/etiologia , Prostatite/etiologia , Prostatite/metabolismo , Ratos , Ratos Endogâmicos , Testosterona/sangue , Testosterona/farmacologia
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