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1.
Cancer Epidemiol Biomarkers Prev ; 33(3): 419-425, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38189661

RESUMO

BACKGROUND: Studies have shown improved survival among individuals with cancer with higher levels of social support. Few studies have investigated social support and overall survival (OS) in individuals with advanced prostate cancer in an international cohort. We investigated the associations of marital status and living arrangements with OS among individuals with advanced prostate cancer in the International Registry for Men with Advanced Prostate Cancer (IRONMAN). METHODS: IRONMAN is enrolling participants diagnosed with advanced prostate cancer (metastatic hormone-sensitive prostate cancer, mHSPC; castration-resistant prostate cancer, CRPC) from 16 countries. Participants in this analysis were recruited between July 2017 and January 2023. Adjusting for demographics and tumor characteristics, the associations were estimated using Cox regression and stratified by disease state (mHSPC, CRPC), age (<70, ≥70 years), and continent of enrollment (North America, Europe, Other). RESULTS: We included 2,119 participants with advanced prostate cancer, of whom 427 died during up to 5 years of follow-up (median 6 months). Two-thirds had mHSPC. Most were married/in a civil partnership (79%) and 6% were widowed. Very few married participants were living alone (1%), while most unmarried participants were living alone (70%). Married participants had better OS than unmarried participants [adjusted HR: 1.44; 95% confidence interval (CI): 1.02-2.02]. Widowed participants had the worst survival compared with married individuals (adjusted HR: 1.89; 95% CI: 1.22-2.94). CONCLUSIONS: Among those with advanced prostate cancer, unmarried and widowed participants had worse OS compared with married participants. IMPACT: This research highlighted the importance of social support in OS within this vulnerable population.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Idoso , Estado Civil , Sistema de Registros , Europa (Continente) , Apoio Social
2.
Eur Urol Open Sci ; 50: 27-30, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36861107

RESUMO

Men with a low prostate-specific antigen (PSA) level (<1 ng/ml) in midlife may extend the rescreening interval (if aged 40-59 yr) or forgo future PSA screening (if aged >60 yr) owing to their low risk of aggressive prostate cancer (PCa). However, there is a subset of men who develop lethal PCa despite low baseline PSA. We investigated how a PCa polygenic risk score (PRS) in addition to baseline PSA impacts the prediction of lethal PCa among 483 men aged 40-70 yr from the Physicians' Health Study followed over a median of 33 yr. We examined the association of the PRS with the risk of lethal PCa (lethal cases vs controls) using logistic regression adjusted for baseline PSA. The PCa PRS was associated with risk of lethal PCa (odds ratio per 1 standard deviation in PRS [OR] 1.79, 95% confidence interval [CI] 1.28-2.49). The association between the PRS and lethal PCa was stronger for those with PSA <1 ng/ml (OR 2.23, 95% CI 1.19-4.21) than for men with PSA ≥1 ng/ml (OR 1.61, 95% CI 1.07-2.42). Our PCa PRS improved the identification of men with PSA <1 ng/ml at greater risk of future lethal PCa who should consider ongoing PSA testing. Patient summary: A subset of men develop fatal prostate cancer despite having low prostate-specific antigen (PSA) levels in middle age. A risk score based on multiple genes can help in predicting men who may be at risk of developing lethal prostate cancer and who should be advised to have regular PSA measurements.

3.
Cancer Prev Res (Phila) ; 16(4): 211-218, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36490225

RESUMO

Avocados contain nutrients and phytochemicals that make it promising for cancer prevention, and chemopreventive properties have been demonstrated in prior studies. Prospective studies on avocado consumption and cancer risk have yet to be conducted. This study included data from 45,289 men in the Health Professionals Follow-Up Study (HPFS, 1986-2016) and 67,039 women in the Nurses' Health Study (NHS, 1986-2014). Avocado consumption was assessed using validated food frequency questionnaires every 4 years. Cox proportional hazards models calculated multivariable HRs and 95% confidence intervals (CI) for associations between avocado consumption and risk of total and site-specific cancers in each cohort. In HPFS, consumption of ≥1 weekly serving of avocados was associated with decreased risk of total (HR, 0.85; 95% CI, 0.80-0.91), colorectal (HR, 0.71; 95% CI, 0.59-0.85), lung (HR, 0.71; 95% CI, 0.57-0.90), and bladder cancer (HR, 0.72; 95% CI, 0.57-0.90). In NHS, avocado consumption was associated with increased risk of breast cancer (HR, 1.21; 95% CI, 1.07-1.37). No associations were observed between avocado consumption and risk of total cancer (HR, 1.06; 95% CI, 0.98-1.14) or other site-specific cancers in NHS. Considering the surprising breast cancer finding, analyses were repeated using data from 93,230 younger women in the parallel NHSII (1991-2017). In NHSII, avocado consumption was not associated with breast cancer risk (HR, 0.93; 95% CI, 0.76-1.13). Overall, avocado consumption may be associated with reduced risk of total and some site-specific cancers in men. The positive association with breast cancer risk in NHS was not seen in the younger NHSII. PREVENTION RELEVANCE: The results of this prospective study suggest that avocado consumption may be associated with decreased risk of total and some site-specific cancers in men. See related Spotlight, p. 187.


Assuntos
Neoplasias da Mama , Persea , Masculino , Humanos , Feminino , Estudos Prospectivos , Seguimentos , Fatores de Risco , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Neoplasias da Mama/prevenção & controle
4.
Prostate Cancer Prostatic Dis ; 25(3): 397-402, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34475523

RESUMO

Prostate cancer has the widest racial disparities of any cancer, and these disparities appear at every stage of the cancer continuum. This review focuses on the disparities in prostate cancer between Black and White men, spanning from prevention and screening to clinical outcomes. We conduct an expansive review of the literature on racial disparities in prostate cancer, interpret the findings, and discuss areas of unmet need in research. We provide an overview of epidemiologic concepts necessary to understanding the current state of prostate cancer disparities, discuss the complexities of studying race, and review potential drivers of disparities in incidence and mortality. We argue that the cause of this disparity is multifactorial and due to a combination of social and environmental factors. The path forward needs to focus on enrolling and retaining Black men in prostate cancer clinical trials and observational studies and identifying potential interventions to improve prevention and clinical outcomes in Black men.


Assuntos
Neoplasias da Próstata , Negro ou Afro-Americano , População Negra , Disparidades em Assistência à Saúde , Humanos , Incidência , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/terapia , População Branca
5.
Biophys J ; 89(6): 4219-33, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16199501

RESUMO

The influence of molecular characteristics on the mutual interaction between peptides and nonionic surfactants has been investigated by studying the effects of surfactants on amphiphilic, random copolymers of alpha-L-amino acids containing lysine residues as the hydrophilic parts. The hydrophobic residues were either phenylalanine or tyrosine. The peptide-surfactant interactions were studied by means of circular dichroism spectroscopy and binding isotherms, as well as by 1D and 2D NMR. The binding of surfactant to the peptides was found to be a cooperative process, appearing at surfactant concentrations just below the critical micellar concentration. However, a certain degree of peptide hydrophobicity is necessary to obtain an interaction with nonionic surfactant. When this prerequisite is fulfilled, the peptide mainly interacts with self-assembled, micelle-like surfactant aggregates formed onto the peptide chain. Therefore, the peptide-surfactant complex is best described in terms of a necklace model, with the peptide interacting primarily with the palisade region of the micelles via its hydrophobic side chains. The interaction yields an increased amount of alpha-helix conformation in the peptide. Surfactants that combine small headgroups with a propensity to form small, nearly spherical micelles were shown to give the largest increase in alpha-helix content.


Assuntos
Peptídeos/análise , Peptídeos/química , Tensoativos/análise , Tensoativos/química , Íons , Ligação Proteica , Eletricidade Estática
6.
Phys Chem Chem Phys ; 7(15): 2970-7, 2005 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16189619

RESUMO

The thermotropic phase behaviour and phase structure of crystalline and non-crystalline n-tetradecyl-beta-D-maltoside (C14G2) and n-hexadecyl-beta-D-maltoside (C16G2) have been investigated by means of differential scanning calorimetry and X-ray techniques. Upon lyophilisation, both compounds form a solid, lamellar phase comprising disordered head groups and hexagonally packed alkyl chains that are suggested to be tilted and interdigitated. This ordered lamellar phase melts into a metastable lamellar liquid crystal, which re-crystallises to a high-temperature crystalline polymorph comprising interdigitated, non-tilted alkyl chains. Remarkably, the high-temperature polymorph of C14G2 has the same melting point as that of C16G2, namely 105 degrees C for both surfactants. A low-temperature polymorph of anhydrous C14G2 crystallises from water at room temperature, whereas the hemihydrate of C14G2 crystallises at 6 degrees C from water, or from chloroform containing trace water. X-ray data suggest both these crystalline modifications to comprise interdigitated and tilted alkyl chains.


Assuntos
Alcanos/química , Glucosídeos/química , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Tensoativos/química , Temperatura
7.
Carbohydr Res ; 340(8): 1529-37, 2005 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-15882846

RESUMO

The solid-state phase behaviour of lyophilised n-dodecyl-beta-D-glucoside (beta-C(12)G(1)), n-dodecyl-beta-D-maltoside (beta-C(12)G(2)) and n-dodecyl-beta-D-maltotrioside (beta-C(12)G(3)) has been investigated by differential scanning calorimetry (DSC) and X-ray techniques. For beta-C(12)G(1), lyophilisation results in a formation of a crystalline anhydrate. The lamellar spacing (37 Angstroms) is consistent with an alkyl chain packing in which the chains are not interdigitated. At 80 degrees C, the material melts into a lamellar liquid crystal with a lamellar spacing of 32 Angstroms, which suggests that the non-interdigitated chain packing of the crystalline state is retained in the liquid crystal. In contrast, lyophilisation of beta-C(12)G(2) and beta-C(12)G(3) results in the formation of a glassy state, best described as a frozen version of the lamellar liquid crystal. For beta-C(12)G(2), the lamellar spacing in the glass and liquid crystal suggests interdigitation of the alkyl chains. The glass transition temperature was found to be 65 degrees C for beta-C(12)G(2) and 100 degrees C for beta-C(12)G(3), which compares favourably with the glass transition of the parent carbohydrates. A second crystalline modification of beta-C(12)G(1) was prepared by precipitation from an aqueous solution at temperatures below the Krafft point (38 degrees C). For this modification, the lamellar distance (24 Angstroms) is consistent with interdigitated alkyl chains. At 50 degrees C, the crystalline material melts into a liquid crystalline phase. The material also readily loses water and rapidly re-crystallises to the anhydrate. The amount of water lost upon drying is consistent with the idea that the material is a monohydrate of beta-C(12)G(1). The drying and re-crystallisation processes give rise to 'pre-transitions' in the DSC thermograms and illustrate the importance of careful control of water in any analysis of the phase behaviour of alkylglycosides.


Assuntos
Glucosídeos/química , Transição de Fase , Butanóis , Varredura Diferencial de Calorimetria , Precipitação Química , Liofilização , Difração de Pó , Solventes , Temperatura , Água/química , Difração de Raios X
8.
Langmuir ; 21(4): 1507-15, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15697301

RESUMO

The effects of salt, temperature, and deuterium oxide on the self-aggregation of n-tetradecyl-beta-d-maltoside (C(14)G(2)) in dilute solution have been investigated by static light scattering, dynamic light scattering (DLS), small-angle neutron scattering (SANS), tensiometry, and capillary viscometry. SANS data show that the micelles can be described as relatively flexible polymer-like micelles with an elliptical cross section, at least at temperatures between 35 and 50 degrees C. The micelles grow in one dimension with increasing temperature and concentration. DLS and viscometry data suggest that the micelle size reaches a maximum at 60-70 degrees C. Comparison of DLS data in D(2)O and H(2)O shows that the micelles are larger in the former case. The effect of salt on the micelle size was found to follow the Hofmeister series. Thus, at constant salt concentration, the micelle size decreases according to the sequence SO(4)(2)(-) > Cl(-) > NO(3)(-) > I(-) > SCN(-), where I(-) and SCN(-) act as salting-in anions. From tensiometric data, it can be concluded that the temperature effects on micelle morphology do not correlate directly with those on unimer solubility. Rather, the temperature effect on the hydrocarbon chain conformation seems to be decisive for the micelle morphology. At constant temperature, on the other hand, the effect of salt and deuterium isotope is attributable to changes in effective headgroup area, including intermolecular interactions and water of hydration.


Assuntos
Óxido de Deutério/química , Maltose/química , Cloreto de Sódio/química , Alquilação , Micelas , Soluções , Tensão Superficial , Temperatura , Viscosidade
9.
Langmuir ; 20(4): 1401-8, 2004 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-15803725

RESUMO

The influence of salt, temperature, and deuterium oxide on the self-aggregation of n-nonyl-beta-D-glucoside (beta-C9G1) in dilute solution has been investigated by static and dynamic light scattering, neutron scattering, and tensiometry. Scattering data show that the micelles can be described as relatively stiff, elongated structures with a circular cross section. With a decrease of temperature, the micelles grow in one dimension, which makes it surprising that the critical micelle concentration (cmc) shows a concomitant increase. On the other hand, substitution of D2O for H2O causes a large increase in micelle size at low temperatures, without any appreciable effect on cmc. With increasing temperature, the deuterium effect on the micelle size diminishes. The effects of salt on the micelle size and cmc were found to follow the Hofmeister series. Thus, at constant salt concentration, the micelle size decreased according to the sequence SO4(2-) > Cl- > Br- > NO3- > I- > SCN-, whereas the effect on cmc displays the opposite trend. Here, I- and SCN are salting-in anions. Similarly, the effects of cations decrease with increasing polarizability in the sequence Li+ > Na+ > K+ > Cs+. At high ionic strength, the systems separate into two micellar phases. The results imply that the size of beta-C9G1 micelles is extremely sensitive to changes in the headgroup size. More specifically, temperature and salt effects on effective headgroup size, including intermolecular interactions and water ofhydration, are suggested to be more decisive for the micelle morphology than the corresponding effects on unimer solubility.


Assuntos
Óxido de Deutério/química , Glicosídeos/química , Sais/química , Adsorção , Ânions , Cátions , Relação Dose-Resposta a Droga , Eletrólitos , Glucosídeos/química , Íons , Luz , Micelas , Modelos Estatísticos , Nêutrons , Sais/farmacologia , Espalhamento de Radiação , Soluções , Tensoativos/química , Temperatura , Fatores de Tempo
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