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Synthetic peptide and peptido-mimetic filaments and tubes represent a diverse class of nanomaterials with a broad range of potential applications, such as drug delivery, vaccine development, synthetic catalyst design, encapsulation, and energy transduction. The structures of these filaments comprise supramolecular polymers based on helical arrangements of subunits that can be derived from self-assembly of monomers based on diverse structural motifs. In recent years, structural analyses of these materials at near-atomic resolution (NAR) have yielded critical insights into the relationship between sequence, local conformation, and higher-order structure and morphology. This structural information offers the opportunity for development of new tools to facilitate the predictable and reproducible de novo design of synthetic helical filaments. However, these studies have also revealed several significant impediments to the latter process – most notably, the common occurrence of structural polymorphism due to the lability of helical symmetry in structural space. This article summarizes the current state of knowledge on the structures of designed peptide and peptido-mimetic filamentous assemblies, with a focus on structures that have been solved to NAR for which reliable atomic models are available. [ABSTRACT FROM AUTHOR]

Background: African American (AA) male survivors of strokes or transient ischemic attacks (TIA) have the highest risk of recurrent stroke when compared to other racial-ethnic men. However, there is a paucity of evidence-based strategies, including organizational, educational, or behavioral interventions, that targets secondary stroke risk reduction in AA men. Methods: Targeted Management for Reducing Stroke Risk (TEAM) is an ongoing, 6-month prospective, randomized controlled trial that will determine whether a curriculum-guided self-management approach, using peer dyads (men who had a stroke or TIA and their care partners) will improve post-stroke care in AA men. Results: The study sample will consist of 160 AA men who have experienced a stroke or TIA within 5 years, randomized to TEAM or Wait-list control group. The primary outcome changes in systolic blood pressure (BP) and high-density lipoprotein (HDL), while secondary outcomes include diastolic BP, total cholesterol, low-density lipoprotein, triglycerides, and glycemic control for diabetics. We hypothesize that AA men in TEAM will have significantly lower systolic BP and higher HDL when compared to AA men in the Wait-list control group at 6-month. Conclusion: Persistent disparities for stroke burden in AA men highlight the need for novel interventions to promote secondary stroke-risk reduction. Building on promising pilot data, TEAM uses a group format, with a nurse and patient co-led intervention focused on AA men and family needs, practice in problem-solving, and attention to emotional and role management. In addition, the TEAM approach may help reduce stroke risk factors and health disparities in AA men. Clinicaltrials.gov Identifier: NCT04402125. [ABSTRACT FROM AUTHOR]

The exquisite structure-function correlations observed in filamentous protein assemblies provide a paradigm for the design of synthetic peptide-based nanomaterials. However, the plasticity of quaternary structure in sequence-space and the lability of helical symmetry present significant challenges to the de novo design and structural analysis of such filaments. Here, we describe a rational approach to design self-assembling peptide nanotubes based on controlling lateral interactions between protofilaments having an unusual cross-α supramolecular architecture. Near-atomic resolution cryo-EM structural analysis of seven designed nanotubes provides insight into the designability of interfaces within these synthetic peptide assemblies and identifies a non-native structural interaction based on a pair of arginine residues. This arginine clasp motif can robustly mediate cohesive interactions between protofilaments within the cross-α nanotubes. The structure of the resultant assemblies can be controlled through the sequence and length of the peptide subunits, which generates synthetic peptide filaments of similar dimensions to flagella and pili. Peptide-based filamentous assemblies are successfully used for generation of structurally ordered materials, but their de novo design and structural characterization is challenging. Here, the authors provide a strategy for the design of self-assembling peptide nanotubes based on modifications of an arginine clasp interaction motif, and report the cryo-EM structures of seven designed nanotubes. [ABSTRACT FROM AUTHOR]

Health-related quality of life (HRQOL) measures among the African American populations have previously been inadequately studied. This study sought to further analyze the quality of life of African American men at the Cleveland Clinic Minority Men’s Health Center and Cleveland Clinic Minority Men’s Health Fair. Subjects were randomly selected at the Minority Health Fair and Minority Men’s Health Center clinics over the duration of 2 weeks to participate in the anonymous survey with the help of independent surveyors. Convenience sampling was done at the Minority Men’s Health Fair and at the Minority Men’s Health Clinics. Participants were administered in-person Short Form-36 (SF-36v2). A total of 83 participants were surveyed, and the response rate from the surveyed population was 100%. The only exclusion criterion for the study was the refusal to participate (n = 0). As compared with healthy U.S. norms, African American men reported lower HRQOL across six health domains: physical functioning (60.69 ± 2.82 vs. 84.2), general health (57.56 ± 2.41 vs. 72), social functioning (72.65 ± 3.17 vs. 83.3), role-emotional (55.89 ± 3.02 vs. 81.3), mental health (61.23 ± 2.34 vs. 74.7), and role-physical (62.5 ± 2.88 vs. 81). The largest difference between the health domains was reported in role limitations due to emotional problems (55.89 ± 3.02 vs. 81.3, 25.4). Marital analysis revealed clinically significant lower HRQOL in married African Americans as compared with nonmarried, statistically significant in physical functioning and physical health component (p < .05). African Americans disproportionally face pervasive disparities in health, as supported by extensive quality of life impairment. No other study, to our knowledge, has used quality of life assessment in African Americans to quantitate how such disparities are affecting important domains in their lives. [ABSTRACT FROM AUTHOR]

To explore the potential effects of race on pathological outcomes of renal tumor and on kidney function preservation in the patients undergoing robotic partial nephrectomy (RPN) at our center. Retrospective review of our institutional review board approved database for African-American (AA) patients undergoing RPN from 2006 to 2014 was performed. AA and non-AA groups were compared with regards to demographics, tumor characteristics, functional data and, oncological outcomes. For functional outcomes, groups were matched (1:1) in terms of age, preoperative estimated glomerular filtration rate (eGFR) and R.E.N.A.L score. From the total of 1005 patients, 84 were AA. Age and the tumor size were comparable between the two groups (2.7 vs. 3 cm; p = 0.29). Proportion of patients with papillary RCC was higher among AAs compared to non-AAs (43.3 vs. 19.4 %; p < 0.001). After matching AA patients with non-AA counterparts (1:1 matching), eGFR preservation at latest follow up after surgery was comparable between groups (84.3 vs. 85 %; p = 0.25). AA race (OR 3.62, p < 0.001), male gender (OR 2.05, p < 0.001) and low preoperative eGFR (OR 0.97, p < 0.001) were predictors of papillary RCC on multivariate analyses. The incidence of papillary RCC is higher in AA patients undergoing RPN. There was no difference in kidney function recovery after robotic partial nephrectomy in both AA and non-AA groups. AA race itself is not a significant factor in determining renal malignancy. Further studies are needed to clarify the impact of higher prevalence of papillary tumors in AA group in terms of long-term oncological and functional outcomes. [ABSTRACT FROM AUTHOR]

Health self-efficacy, a measure of one’s self-assurance in taking care of their own health, is known to contribute to a range of health outcomes that has been under examined among African American men. The purpose of this investigation was to identify and contextualize predictors of general health self-efficacy in this population. A cross-sectional sample of surveys from 558 African American was examined. These men were older than 18 years, could read and write English, and attended a hospital-based community health fair targeting minority men in 2011. The outcome of interest was health self-efficacy, which was assessed by asking, “Overall, how confident are you in your ability to take good care of your health?” Responses ranged from 1 (not confident at all) to 5 (completely confident). Covariates included age, self-rated health, health insurance status, having a regular physician, and being a smoker. The mean age of participants was 54.4 years, and 61.3% of participants indicated confidence in their ability to take good care of their health. Older age and being a smoker were inversely associated with the outcome. Good self-rated health, having health insurance, and having a regular doctor were positively associated with reports of health self-efficacy. Findings suggest that multiple points of connection to the health care system increase the likelihood of health self-efficacy for this sample and interventions to support older African American men who may evaluate their own health status as poor and who may face barriers to health care access are implicated. [ABSTRACT FROM AUTHOR]

Background. Health self-efficacy (the confidence to take care of one’s health) is a key component in ensuring that individuals are active partners in their health and health care. The purpose of this study was to determine the association between financial hardship and health self-efficacy among African American men and to determine if unmet medical need due to cost potentially mediates this association. Method. Cross-sectional analysis was conducted using data from a convenience sample of African American men who attended a 1-day annual community health fair in Northeast Ohio (N = 279). Modified Poisson regression models were estimated to obtain the relative risk of reporting low health self-efficacy. After adjusting for sociodemographic characteristics, those reporting financial hardship were 2.91 times, RR = 2.91 (confidence interval [1.24, 6.83]; p < .05), more likely to report low health self-efficacy. When unmet medical need due to cost was added to the model, the association between financial hardship and low health self-efficacy was no longer statistically significant. Conclusion. Our results suggest that the association between financial hardship and health self-efficacy can be explained by unmet medical need due to cost. Possible intervention efforts among African American men with low financial resources should consider expanding clinical and community-based health assessments to capture financial hardship and unmet medical need due to cost as potential contributors to low health self-efficacy. [ABSTRACT FROM AUTHOR]

Renal transplantation has profound improvements in mortality, morbidity, and overall quality of life compared to renal replacement therapy. This report aims to illustrate the use of ex-vivo partial nephrectomy in a patient with a renal angiomyolipoma prior to living donor transplantation. The surgical outcomes of the donor nephrectomy and recipient transplantation are reported with 2 years of follow-up. Both the donor and recipient are healthy and without any significant comorbidities. In conclusion, urologic techniques such as partial nephrectomy can be used to expand the living donor pool in carefully selected and well informed transplant recipients. Our experience demonstrated a safe and positive outcome for both the recipient and donor, and is consistent with other reported outcomes in the literature. [ABSTRACT FROM AUTHOR]

BACKGROUND: Prostate cancer is the most frequently diagnosed malignancy in men in the United States, with evenhigher prevalence and death rates among black men. The authors sought to compare trends in prostate-specific anti-gen (PSA), age, and prostate-cancer detection among black and white men in our region during a 16-year period.METHODS: This was a retrospective study of patient archives between 1990 through 2006. Data collection wasaccomplished by examining patients' charts and electronic medical records. Data from 5570 patients, of whom 911were black, were analyzed statistically by testing and comparing parameters over time. RESULTS: During this 16-year period, mean age at the time of initial diagnostic prostate biopsy did not change in either group, despite what wehad believed about the effects of patient education and screening campaigns. However, prostate-cancer detectionrates did decrease during the time period studied. Over time, the authors also observed significant decreases in thesensitivity and specificity of PSA as a screening tool. Indeed, analysis of more recent cases demonstrated a positivepredictive value comparable to a coin toss. While Gleason scores remained relatively stable over time, reporting ofprostate intraepithelial neoplasia (PIN) and inflammation increased. CONCLUSIONS: Using lower PSA thresholds, promoting younger screening age, and increasing efforts to educate the public have not seemed to influence age attime of diagnostic testing, which may reflect other factors such as usefulness of screening, physician referral patterns,patient compliance, and other sociodemographic issues. The usefulness of PSA as a screening tool appears to bediminishing. [ABSTRACT FROM AUTHOR]

OBJECTIVE To investigate the effect of placing a prophylactic drain during renal transplantation on the incidence of lymphocele, wound complication and deep venous thrombosis (DVT) in renal transplant recipients induced with sirolimus vs calcineurin inhibitors (CNI), as sirolimus-based immunosuppression is a risk factor for the formation of fluid collections after transplantation. PATIENTS AND METHODS We analysed 165 consecutive adult renal transplant patients at our institution between January 2004 and February 2005. Group 1 (84) did not receive an intraoperative drain and group 2 (81) did. Recipients were analysed within each group based on immunosuppression (sirolimus or CNI) and whether they had wound complication, fluid collection, lymphocele treatment, or DVT. RESULTS In group 1 and 2, respectively, the wound complication rate was 22.6% vs 13.6% ( P = 0.134), the fluid collection rate 45.2% vs 16.% ( P < 0.001), the lymphocele treatment rate 19.0% vs 2.5% ( P = 0.001) the DVT rate 14.3% vs 4.9% ( P = 0.043) the fluid collection rate (for CNI) 26.5% vs 16.0% ( P = 0.246), the lymphocele treatment rate (for CNI) 5.9% vs 0% ( P = 0.084), the fluid collection rate (sirolimus) 58.0% vs 16.1% ( P < 0.001) and lymphocele treatment rate (sirolimus) 28% vs 6.5% ( P = 0.018). Multivariate analysis of risk factors for fluid collection showed significance for no drain (odds ratio 3.30, P = 0.002), associated wound complication (2.41, P = 0.041) and sirolimus (2.48, P = 0.015). CONCLUSIONS Placing a drain during transplantation decreased the incidence of fluid collection, lymphocele treatment and DVT. The reduction of fluid collection and lymphocele were significant for patients treated with sirolimus. We recommend placing a drain in patients undergoing induction with sirolimus-based immunosuppression. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The introduction of the microemulsion formulation of cyclosporine (CsA) (Neoral – NEO) has been shown to provide improved absorption and less intrapatient variability than the previous formulation (Sandimmune – SIM) in kidney transplant recipients. It has been suggested that the use of the microemulsion formulation results in less acute rejection, and therefore permits better long-term transplant outcomes. Our aim was to determine whether the microemulsion formulation of cyclosporine has reduced the long-term (5 yr or more) rates of chronic rejection (allograft nephropathy) in a renal transplant population. Methods: The study population included 792 (508 cadaveric and 284 living donor) transplants performed in 786 patients at the Cleveland Clinic Foundation and its affiliate hospitals between July 1, 1987 and July 1, 1998. Patients who were less than 18-yr-old or had less than 12 months of graft function were excluded from the analysis. Over 90% of the cadaveric and 11% of the live donor recipients were given an induction antibody. A total of 591 patients were given the SIM formulation and 201 the NEO formulation of cyclosporine. Additional maintenance therapy included either azathioprine or mycophenolate mofetil, and steroids. All patients were followed to graft loss, death, or return to dialysis. The NEO group was followed until December 2001. The diagnosis of acute rejection was biopsy confirmed in >92% of cases. Chronic rejection was identified by clinical and biopsy criteria. Demographic and clinical data was collected from medical records, interviews, and phone contact with patients and treating physicians. Results: The mean follow-up was 84 ± 31 months for the SIM group, and 54 ± 14 months for the NEO group. At 70 months there was no significant difference (p = 0.17) – actuarial patient survival between the SIM (90.7%) vs. the NEO (93%) treated patients. In addition, at 70 months there was no... [ABSTRACT FROM AUTHOR]