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1.
BMC Infect Dis ; 22(1): 591, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35787257

RESUMO

BACKGROUND: Microalbuminuria is an independent risk factor for cardiovascular and kidney disease and a predictor of end organ damage, both in the general population and in persons with HIV (PWH). Microalbuminuria is also an important risk factor for mortality in PWH treated with antiretroviral therapy (ART). In the ongoing Renal Risk Reduction (R3) study in Nigeria, we identified a high prevalence of microalbuminuria confirmed by two measurements 4-8 weeks apart in ART-experienced, virologically suppressed PWH. Although Stage 1 or 2 hypertension and exposure to potentially nephrotoxic antiretroviral medications were common in R3 participants, other traditional risk factors for albuminuria and kidney disease, including diabetes, APOL1 high-risk genotype, and smoking were rare. Co-infection with endemic pathogens may also be significant contributors to albuminuria, but co-infections were not evaluated in the R3 study population. METHODS: In Aim 1, we will cross-sectionally compare the prevalence of albuminuria and established kidney disease risk factors in a cohort of PWH to age- and sex-matched HIV-negative adults presenting for routine care at the Aminu Kano Teaching Hospital in Kano, Nigeria. We will leverage stored specimens from 2500 R3 participants and enroll an additional 500 PLWH recently initiated on ART (≤ 24 months) and 750 age- and sex-matched HIV-negative adults to determine the contribution of HIV, hypertension, and other comorbid medical conditions to prevalent albuminuria. In Aim 2, we will follow a cohort of 1000 HIV-positive, ART-treated and 500 HIV-negative normoalbuminuric adults for 30 months to evaluate the incidence and predictors of albuminuria. DISCUSSION: The findings from this study will support the development of interventions to prevent or address microalbuminuria in PWH to reduce kidney and cardiovascular morbidity and mortality. Such interventions might include more intensive monitoring and treatment of traditional risk factors, the provision of renin-angiotensin aldosterone system or sodium-glucose cotransporter-2 inhibitors, consideration of changes in ART regimen, and screening and treatment for relevant co-infections.


Assuntos
Coinfecção , Diabetes Mellitus Tipo 2 , Infecções por HIV , Hipertensão , Nefropatias , Inibidores do Transportador 2 de Sódio-Glicose , Adulto , Albuminúria/epidemiologia , Albuminúria/etiologia , Apolipoproteína L1 , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Nigéria/epidemiologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
2.
Kidney Int ; 100(1): 146-154, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33901548

RESUMO

HIV-positive adults are at risk for various kidney diseases, and apolipoprotein 1 (APOL1) high-risk genotypes increase this risk. This study aimed to determine the prevalence and ethnic distribution of APOL1 risk genotypes among a cohort of HIV-positive Nigerian adults and explore the relationship between APOL1 risk variant status with albuminuria and estimated glomerular filtration rate (eGFR). We conducted a cross-sectional study among 2 458 persons living with HIV who attended an HIV clinic in northern Nigeria and had received antiretroviral therapy for a minimum of six months. We collected two urine samples four-eight weeks apart to measure albumin excretion, and blood samples to measure eGFR and determine APOL1 genotype. The frequency of APOL1 high-risk genotype was 6.2%, which varied by ethnic group: Hausa/Fulani (2.1%), Igbo (49.1%), and Yoruba (14.5%). The prevalence of microalbuminuria (urine/albumin creatinine ratio 30- 300 mg/g) was 37%, and prevalence of macroalbuminuria (urine/albumin creatinine ratio over 300 mg/g) was 3%. The odds of microalbuminuria and macroalbuminuria were higher for participants with the APOL1 high-risk genotype compared to those carrying the low-risk genotype ([adjusted odds ratio 1.97, 95% confidence interval 1.37-2.82] and [3.96, 1.95-8.02] respectively). APOL1 high-risk genotype participants were at higher risk of having both an eGFR under 60 ml/min/1.73m2 and urine/albumin creatinine ratio over 300 mg/g (5.56, 1.57-19.69). Thus, we found a high proportion of HIV-positive, antiretroviral therapy-experienced, and largely virologically suppressed adults had microalbuminuria. Hence, although the high-risk APOL1 genotype was less prevalent than expected, it was strongly associated with some level of albuminuria.


Assuntos
Apolipoproteína L1 , Infecções por HIV , Adulto , Apolipoproteína L1/genética , Apolipoproteínas/genética , População Negra , Estudos Transversais , Taxa de Filtração Glomerular , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/genética , Humanos , Rim , Nigéria/epidemiologia , Fenótipo , Fatores de Risco
3.
Curr HIV/AIDS Rep ; 18(4): 289-298, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34086250

RESUMO

PURPOSE OF REVIEW: Clinical trials represent a bedrock for measuring efficacy of interventions in biomedical research, but recruitment into clinical trials remains a challenge. Few data have focused on recruitment strategies from the perspective of clinical trial teams, especially in low- and middle-income countries (LMIC), where HIV is most prevalent. RECENT FINDINGS: We summarized data from the literature and our experience with recruitment for the Renal Risk Reduction trial, aimed at reducing risk of kidney complications among people living with HIV in Nigeria. Using an implementation science framework, we identified strategies that contributed to successful clinical trial recruitment. For strategies that could not be categorized by this framework, we summarized key features according to selected action, actor, target, context, and time. We identified how these identified strategies could map to subsequent implementation outcomes at the patient and provider/health system level, as well as capacity-building efforts to meet needs identified by LMIC partners, which is a priority for success. Our experience highlights the importance of considering implementation outcomes, and the strategies necessary to achieve those outcomes early, in the planning and execution of clinical trials. Clinical trial recruitment can be optimized via methodologies grounded in implementation science.


Assuntos
Países em Desenvolvimento , Infecções por HIV , Infecções por HIV/prevenção & controle , Humanos , Rim , Nigéria , Comportamento de Redução do Risco
4.
Health Res Policy Syst ; 19(1): 32, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691722

RESUMO

Antiretroviral therapy has turned HIV into a chronic condition, with morbidity from HIV-associated noncommunicable diseases (NCDs) becoming more common as HIV-infected individuals live longer. In Nigeria, the additional challenge of an under-capacitated health system highlights the need for skilled clinical investigators who can generate evidence to tackle the double burden of HIV and NCDs. The Vanderbilt-Nigeria Building Research Capacity in HIV and Non-communicable Diseases (V-BRCH) programme is a training platform to create a cohort of skilled Nigerian investigators with the capacity to lead independent clinical trial research focused on the intersection of HIV and NCDs. V-BRCH will solidify an atmosphere of continuous mentoring and skills acquisition for physician faculty at the Aminu Kano Teaching Hospital via short- and medium-term learning opportunities, paired mentoring arrangements, and mentored research projects. Trainees will attend an annual faculty enrichment programme in Nashville, in addition to on-site workshops in Nigeria on HIV-associated NCD epidemiology, clinical trials methodology, evidence synthesis, qualitative research methods, stakeholder engagement, knowledge translation, and grant writing. Research-oriented junior faculty will undergo focused training in clinical trials administration and regulatory oversight. Scholars will share best practices through mentoring panels, regular 'Works in Progress' meetings, and monthly career development seminars. Competitive seed grants will be provided to mentor-mentee teams to promote targeted in-country pilot studies focused on HIV-associated NCDs. For long-term training, physician scientists will be supported to undergo enhanced Master of Public Health (MPH) training at Bayero University in Nigeria and Master of Science in Clinical Investigation (MSCI) training at Vanderbilt. Short-term regional courses, staff development workshops, and MPH curriculum refinement will help to strengthen institutional capacity in HIV-associated NCD clinical trial research. V-BRCH will create a cohort of skilled Nigerian scientists who will be able to compete for independent funding and design and implement high quality research that will generate evidence to inform policy and practice and lead to improved outcomes for Nigerians impacted by HIV-associated NCDs.


Assuntos
Fortalecimento Institucional , Infecções por HIV , Doenças não Transmissíveis , Infecções por HIV/tratamento farmacológico , Humanos , Mentores , Nigéria , Pesquisadores
5.
J Infect Dis ; 218(8): 1219-1227, 2018 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-29800222

RESUMO

Background: The purpose of this study was to assess genital recurrence of human papillomavirus (HPV) genotypes included in the 9-valent vaccine and to investigate factors associated with recurrence among men in the HPV Infection in Men (HIM) Study. Methods: Men were followed every 6 months for a median of 3.7 years. HPV genotypes were detected using Roche linear array. Factors associated with type-specific HPV recurrence (infections occurring after a ≥12-month infection-free period) were assessed. Results: In type-specific analyses, 31% of prior prevalent and 20% of prior incident infections recurred. Among prevalent infections, HPV types 52, 45, 16, 58, and 6 and among incident infections, HPV types 58, 52, 18, 16, and 11 had the highest rates of recurrence. New sexual partners (male or female) and frequency of sexual intercourse with female partners were associated with HPV-6, -16, -31, and -58 infection recurrence. In grouped analyses, lifetime and new male sexual partners were associated with recurrence of prior incident infection with any of the 9 HPV types. Conclusions: Recurrence of genital HPV infections is relatively common among men and associated with high-risk sexual behavior. Further studies are needed to understand the role of HPV recurrence in the etiology of HPV-associated diseases.


Assuntos
Papillomaviridae/classificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Doenças Virais Sexualmente Transmissíveis/epidemiologia , Doenças Virais Sexualmente Transmissíveis/virologia , Brasil/epidemiologia , DNA Viral/isolamento & purificação , Feminino , Florida/epidemiologia , Genótipo , Humanos , Masculino , México/epidemiologia , Papillomaviridae/genética , Papillomaviridae/imunologia , Recidiva , Assunção de Riscos , Comportamento Sexual , Vacinas Virais
6.
Int J Cancer ; 140(2): 337-345, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27681815

RESUMO

The purpose of this study was to assess whether the incidence of histopathologically confirmed condyloma and penile intraepithelial neoplasia (PeIN) and rates of genital HPV infection progression to these lesions differs by country (Brazil, Mexico and the U.S.). At each visit, lesions were biopsied and were categorized by pathologic diagnoses. The Linear Array genotyping method was used to identify HPV genotypes from genital swabs, while the INNO-LiPA HPV Genotyping Extra method was used for tissue specimens. Age-specific analyses were conducted for lesion incidence by country, with Kaplan-Meier estimation of cumulative incidence. The proportion of HPV infections that progressed to condyloma and PeIN, the median time to lesion development and the incidence rates were estimated by country. When comparing demographic and sexual characteristics across the three countries, sexual orientation (p = 0.008) and lifetime number of female sexual partners (p < 0.0001) were differentially associated with lesion incidence in the three countries. Condyloma incidence in Brazil and the U.S. decreased with age, while incidence remained constant across the lifespan in Mexico. There were no differences by country and age for PeIN incidence. HPV types 6 and 11 were the most common types to progress to condyloma and HPV types 16, 6 and 11 were the most common types to progress to PeIN in all three countries. The continuous risk of condyloma and PeIN across all age groups and countries in this study emphasizes the need to ensure that strong HPV immunity, such as that obtained through vaccination, is maintained across the lifespan of men.


Assuntos
Doenças dos Genitais Masculinos/epidemiologia , Doenças dos Genitais Masculinos/virologia , Infecções por Papillomavirus/epidemiologia , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Doenças dos Genitais Masculinos/etiologia , Genótipo , Humanos , Incidência , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/etiologia , Infecções por Papillomavirus/virologia , Fatores de Risco , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Estados Unidos/epidemiologia , Adulto Jovem
7.
Clin Infect Dis ; 62(11): 1367-1374, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26962079

RESUMO

BACKGROUND: Given high rates of anal disease, we investigated the natural history of high-risk anal human papillomavirus (HPV) among a multinational group of men who have sex with men (MSM) aged 18-64 years. METHODS: Anal specimens from human immunodeficiency virus-negative men from Brazil, Mexico, and the United States were genotyped. Over 2 years, 406 MSM provided evaluable specimens every 6 months for ≥2 visits. These men were stratified into men who have sex only with men (MSOM, n = 70) and men who have sex with women and men (MSWM, n = 336). Persistence was defined as ≥12 months' type-specific duration and could begin with either a prevalent or incident infection. Prevalence ratios and 95% confidence intervals were calculated by Poisson regression. RESULTS: Median follow-up time was 2.1 years. Retention was 82%. Annual cumulative incidence of 9-valent vaccine types was 19% and 8% among MSOM and MSWM, respectively (log-rank P = .02). Duration of anal HPV did not differ for MSOM and MSWM and was a median of 6.9 months for HPV-16 after combining men from the 2 groups. Among men with prevalent high-risk infection (n = 106), a total of 36.8%, retained the infection for at least 24 months. For those with prevalent HPV-16 (n = 27), 29.6% were persistent for at least 24 months. Persistence of high-risk HPV was associated with number of male anal sex partners and inversely associated with number of female sex partners. CONCLUSIONS: MSM with prevalent high-risk HPV infection should be considered at increased risk for nontransient infection.


Assuntos
Doenças do Ânus/epidemiologia , Doenças do Ânus/virologia , Homossexualidade Masculina/estatística & dados numéricos , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Adolescente , Adulto , América/epidemiologia , Canal Anal/virologia , Bissexualidade/estatística & dados numéricos , Estudos de Coortes , DNA Viral/análise , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Gen Virol ; 97(12): 3291-3301, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27902363

RESUMO

Data on cutaneous human papillomavirus (HPV) seroprevalence are primarily derived from skin cancer case-control studies. Few studies have reported the seroprevalence of cutaneous HPV among healthy men. This study investigated the seroprevalence of cutaneous HPV types and associated risk factors among men residing in Brazil, Mexico and the USA. Six hundred men were randomly selected from the HPV Infection in Men study. Archived serum specimens were tested for antibodies against 14 cutaneous HPV genotypes, ß-HPV types (5/8/12/14/17/22/23/24/38/48), α-HPV 27, γ-HPV 4, µ-HPV1 and ν-HPV 41 using a glutathione S-transferase L1-based multiplex serology assay. Risk factor data were collected by a questionnaire. Binomial proportions were used to estimate seroprevalence, and logistic regression to examine factors associated with seropositivity. Overall, 65.4 % of men were seropositive to ≥1 of the 14 cutaneous HPV types, and 39.0 % were positive for ≥1 ß-HPV types. Seroprevalence was 8.9, 30.9, 28.6 and 9.4 % for α-HPV 27, γ-HPV 4, µ-HPV 1 and ν-HPV 41, respectively. In multivariate analyses, seropositivity for any cutaneous HPV type was associated with higher education [adjusted odds ratio (AOR) 1.75; 95 % confidence interval (CI) 1.08-2.83], and seropositivity of any ß-HPV type was significantly associated with increasing age (AOR 1.72; 95 % CI 1.12-2.63, for men aged 31-44 years vs men aged 18-30 years). Other factors associated with various type-specific cutaneous HPV seropositivity included country, circumcision and lifetime number of male sexual partners. These data indicate that exposure to cutaneous HPV is common. Future studies are needed to assess the role of cutaneous HPV in diseases.


Assuntos
Papillomaviridae/imunologia , Infecções por Papillomavirus/sangue , Dermatopatias/virologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Estudos Prospectivos , Estudos Soroepidemiológicos , Dermatopatias/sangue , Adulto Jovem
9.
J Infect Dis ; 211(7): 1060-7, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25344518

RESUMO

BACKGROUND: Human papillomavirus (HPV) causes external genital lesions (EGLs) in men, including condyloma and penile intraepithelial neoplasia (PeIN). We sought to determine the incidence of pathologically confirmed EGLs, by lesion type, among men in different age groups and to evaluate the HPV types that were associated with EGL development. METHODS: HPV Infection in Men (HIM) study participants who contributed ≥2 visits from 2009-2013 were included in the biopsy cohort. Genotyping by an HPV line-probe assay was performed on all pathologically confirmed EGLs. Age-specific analyses were conducted for incident EGLs, with Kaplan-Meier estimation of cumulative incidence. RESULTS: This biopsy cohort included 2754 men (median follow-up duration, 12.4 months [interquartile range, 6.9-19.2 months]). EGLs (n = 377) were pathologically confirmed in 228 men, 198 of whom had incident EGLs. The cumulative incidence of any EGL was highest among men <45 years old and, for condyloma, decreased significantly over time with age. The genotype-specific incidence of EGL varied by pathological diagnoses, with high- and low-risk genotypes found in 15.6% and 73.2% of EGLs, respectively. Condyloma primarily contained HPV 6 or 11. While PeIN lesions primarily contained HPV 16, 1 PeIN III lesion was positive for HPV 6 only. CONCLUSION: Low- and high-risk HPV genotypes contribute to the EGL burden. Men remain susceptible to HPV-related EGLs throughout the life span, making it necessary to ensure the longevity of immune protection against the most common causative HPV genotypes.


Assuntos
Condiloma Acuminado/virologia , Neoplasias dos Genitais Masculinos/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Pênis/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Condiloma Acuminado/epidemiologia , Condiloma Acuminado/patologia , Seguimentos , Neoplasias dos Genitais Masculinos/epidemiologia , Neoplasias dos Genitais Masculinos/patologia , Genótipo , Papillomavirus Humano 11/genética , Papillomavirus Humano 11/isolamento & purificação , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 6/genética , Papillomavirus Humano 6/isolamento & purificação , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Prevalência , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
10.
J Med Virol ; 87(10): 1777-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25945468

RESUMO

Early HPV infection in males is difficult to detect clinically and pathologically. This study assessed histopathology in diagnosing male genital HPV. External genital lesions (n = 352) were biopsied, diagnosed by a dermatopathologist, and HPV genotyped. A subset (n = 167) was diagnosed independently by a second dermatopathologist and also re-evaluated in detail, tabulating the presence of a set of histopathologic characteristics related to HPV infection. Cases that received discrepant diagnoses or HPV-related diagnoses were evaluated by a third dermatopathologist (n = 163). Across dermatopathologists, three-way concordance was fair (k = 0.30). Pairwise concordance for condyloma was fair to good (k = 0.30-0.67) and poor to moderate for penile intraepithelial neoplasia (k = -0.05 to 0.42). Diagnoses were 44-47% sensitive and 65-72% specific for HPV 6/11-containing lesions, and 20-37% sensitive and 98-99% specific for HPV 16/18. Presence of HPV 6/11 was 75-79% sensitive and 35% specific for predicting pathologic diagnosis of condyloma. For diagnosis of penile intraepithelial neoplasia, HPV 16/18 was 95-96% specific but only 40-64% sensitive. Rounded papillomatosis, hypergranulosis, and dilated vessels were significantly (P < 0.05) associated with HPV 6/11. Dysplasia was significantly (P = 0.001) associated with HPV 16/18. Dermatopathologists' diagnoses of early male genital HPV-related lesions appear discordant with low sensitivity, while genotyping may overestimate clinically significant HPV-related disease. Rounded papillomatosis, hypergranulosis, and dilated vessels may help establish diagnosis of early condyloma.


Assuntos
Doenças dos Genitais Masculinos/diagnóstico , Doenças dos Genitais Masculinos/patologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/patologia , Neoplasias Penianas/diagnóstico , Neoplasias Penianas/virologia , Adulto , Biópsia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Carcinoma in Situ/virologia , Condiloma Acuminado/diagnóstico , Condiloma Acuminado/patologia , Condiloma Acuminado/virologia , Genótipo , Papillomavirus Humano 11/genética , Papillomavirus Humano 11/isolamento & purificação , Papillomavirus Humano 11/patogenicidade , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 16/patogenicidade , Humanos , Masculino , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/virologia , Pênis/patologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
11.
Molecules ; 20(1): 1643-60, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25608045

RESUMO

The molecular chaperone Hsp90 is regulated by co-chaperones such as p50Cdc37, which recruits a wide selection of client protein kinases. Targeted disruption of the Hsp90-p50Cdc37 complex by protein-protein interaction (PPI) inhibitors has emerged as an alternative strategy to treat diseases characterized by aberrant Hsp90 activity. Using isothermal microcalorimetry, ELISA and GST-pull down assays we evaluated reported Hsp90 inhibitors and nucleotides for their ability to inhibit formation of the human Hsp90ß-p50Cdc37 complex, reconstituted in vitro from full-length proteins. Hsp90 inhibitors, including the proposed PPI inhibitors gedunin and H2-gamendazole, did not affect the interaction of Hsp90 with p50Cdc37 in vitro. Phosphorylation of Hsp90 and p50Cdc37 by casein kinase 2 (CK2) did not alter the thermodynamic signature of complex formation. However, the phosphorylated complex was vulnerable to disruption by ADP (IC50 = 32 µM), while ATP, AMPPNP and Hsp90 inhibitors remained largely ineffective. The differential inhibitory activity of ADP suggests that phosphorylation by CK2 primes the complex for dissociation in response to a drop in ATP/ADP levels. The approach applied herein provides robust assays for a comprehensive biochemical evaluation of potential effectors of the Hsp90-p50Cdc37 complex, such as phosphorylation by a kinase or the interaction with small molecule ligands.


Assuntos
Caseína Quinase II/metabolismo , Proteínas de Ciclo Celular/metabolismo , Chaperoninas/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Nucleotídeos/farmacologia , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Calorimetria , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Cinética , Modelos Moleculares , Fosforilação/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Bibliotecas de Moléculas Pequenas/farmacologia , Termodinâmica
12.
J Basic Microbiol ; 54(4): 322-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23686727

RESUMO

Terreic acid is a metabolite with antibiotic properties produced by the fungus Aspergillus terreus, but its cellular target remains unknown. We recently reported that terreic acid inactivates the bacterial cell wall biosynthetic enzyme MurA in vitro by covalent reaction with residue Cys115 in a similar manner as the MurA-specific antibiotic fosfomycin. To address if terreic acid also targets MurA in vivo, we conducted antibacterial studies using selected E. coli strains in parallel with fosfomycin. While overexpression of MurA conferred resistance to fosfomycin, it did not protect cells treated with terreic acid. Furthermore, flow cytometry revealed that the antibiotic action of terreic acid appears to be primarily bacteriostatic, as opposed to the bactericidal action observed for fosfomycin. Combined, the data suggest that MurA is not the molecular target of terreic acid and that the antibiotic activity of terreic acid proceeds through a different mechanism of action. The methodology applied here provides a reliable and convenient tool to rapidly assess the potential of newly discovered in vitro inhibitors to target residue Cys115 of MurA in the cell.


Assuntos
Alquil e Aril Transferases/antagonistas & inibidores , Antibacterianos/farmacologia , Fosfomicina/farmacologia , Aspergillus , Proliferação de Células/efeitos dos fármacos , Farmacorresistência Bacteriana , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Mutação , Quinonas/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-38098733

RESUMO

Biomedical HIV research is growing in West Africa, but biostatistical expertise is lagging. The Vanderbilt-Nigeria Biostatistics Training Program (VN-BioStat) seeks to establish a research and training platform for biostatisticians doing HIV-related research in Nigeria. The objectives of the program are: 1) Host two Nigerian data scientists per year (a total of 10 over 5 years) at Vanderbilt University Medical Center to gain hands-on biostatistics training and experience via one-year fellowships. Eligible trainees will be junior investigators with PhDs or nearing completion of their PhDs in statistics or related fields, including mathematics and computer science. 2) Conduct annual workshops in Nigeria to provide biostatistics training. Trainees will undertake biostatistics coursework and hands-on training and participate in mentorship as biostatisticians involved in HIV research. Trainees will be at Vanderbilt for a full year and be part of an active biostatistics department. They will be immersed in a dry-lab HIV biostatistics project in collaboration with a Nigerian HIV research project and lead a methodologically focused research project. They will also participate in a one-month research training/grant writing program in Nashville. The VN-BioStat program will build on the existing momentum of ongoing initiatives to enhance research capacity in Nigeria by developing biostatistics leadership. VN-BioStat trainees will interact with investigators from Nigeria to provide collaborative biostatistical assistance with study design and data analysis, thus gaining real-world experience that will benefit the trainees and the broader research community in Nigeria.

14.
Int J Stat Probab ; 12(6): 66-72, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38318241

RESUMO

The Vanderbilt-Nigeria Biostatistics Training Program (VN-BioStat) aims to establish a research and training platform for biostatisticians doing HIV-related research in Nigeria, including enhancing mid-level biostatistics capacity through annual workshops. This paper describes findings from the inaugural workshop in Kano, Nigeria. Participants were surveyed before and after the workshop to assess their self-perceived familiarity with and confidence in their abilities to use statistical software and apply specific statistical techniques, as well as to gather feedback regarding the conduct of the workshop and future topic areas. Of the 23 participants enrolled in the workshop, 22 (96%) completed both pre- and post-workshop assessments. In both pre-workshop and post-workshop surveys, participants ranked their confidence in statistical skills using Likert scales. Scores were transformed to a 0-100 scale, and averages computed. Participants also shared open-ended feedback about the workshop and suggested future topic areas. Before the training, the average participant reported having either a "beginner" (30% of participants) or "moderate" (43%) level of familiarity with R. Many participants (65%) rated themselves as having "moderate" or "expert" familiarity with SPSS. Pre-workshop averages for confidence ranged from 26 to 64, with lowest confidence in "expanding continuous covariates in regression models and interpret results" and highest confidence in "fitting and interpreting results from a linear regression model". Post-workshop averages for confidence were all above 70. The lowest post-workshop score (74) was for "fit and interpret results from a semiparametric linear transformation model". The greatest increase in confidence was observed in "expanding continuous covariates in regression models using splines and interpreting results" and the lowest increase was in "fitting and interpreting results from a linear regression model." Participants offered positive feedback on instructor effectiveness (4.9/5) and overall course quality (4.9/5). While the overall course was rated on a 0-100 scale as "moderately difficult" (mean ± SD: 40.5 ± 17.5), the participants felt the course was highly organized (87.7 ± 17.8), and the information was moderately easy to learn (81.9 ± 15.9). Suggestions for future workshops included providing supplementary resources for out-of-classroom learning and releasing codes in advance to enhance participants' preparation. Among suggestions for future workshop topics, 80% of respondents listed survival analysis. Lessons learned provide insight into how short-term training opportunities can be leveraged to build biostatistics capacity in similar settings.

15.
Am J Trop Med Hyg ; 108(4): 660-671, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36806489

RESUMO

In this mixed-methods study, we explore themes that emerged from a survey assessing the programmatic experiences of mentors and administrators at institutions in low- and middle-income countries (LMICs) hosting trainees supported by the Fogarty International Center's Global Health Program for Fellows and Scholars. A total of 89 of 170 potential respondents representing 31 countries completed the survey (response rate, 52.4%). There was agreement among respondents that their institutions received sufficient funds to support trainees and had the capacity to manage operational and financial aspects of the program. A majority also agreed that both LMIC and U.S. trainees were beneficial to the host institutions, and that trainee projects were relevant to the needs of the host country. Respondents felt that program benefits to LMIC trainees could be improved by increasing the research consumables budget, increasing the flexibility of program timelines, and increasing engagement between LMIC and U.S. trainees and institutions. Respondents indicated that both U.S. and LMIC trainees behaved professionally (including demonstrating respectful and ethical behavior) and took appropriate initiative to conduct their research projects. Findings from this study will help inform innovations to similar training initiatives that will enhance sustainability and improve program performance, and will be responsive to local needs.


Assuntos
Pesquisa Biomédica , Países em Desenvolvimento , Humanos , Saúde Global , Pesquisa Biomédica/educação , Inquéritos e Questionários , Mentores
16.
Chembiochem ; 13(14): 2128-36, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-22893598

RESUMO

In an attempt to identify novel small-molecule ligands of cyclin-dependent kinase 2 (CDK2) with potential as allosteric inhibitors, we have devised a robust and cost-effective fluorescence-based high-throughput screening assay. The assay is based on the specific interaction of CDK2 with the extrinsic fluorophore 8-anilino-1-naphthalene sulfonate (ANS), which binds to a large allosteric pocket adjacent to the ATP site. Hit compounds that displace ANS directly or indirectly from CDK2 are readily classified as ATP site binders or allosteric ligands through the use of staurosporine, which blocks the ATP site without displacing ANS. Pilot screening of 1453 compounds led to the discovery of 12 compounds with displacement activities (EC(50) values) ranging from 6 to 44 µM, all of which were classified as ATP-site-directed ligands. Four new type I inhibitor scaffolds were confirmed by X-ray crystallography. Although this small compound library contained only ATP-site-directed ligands, the application of this assay to large compound libraries has the potential to reveal previously unrecognized chemical scaffolds suitable for structure-based design of CDK2 inhibitors with new mechanisms of action.


Assuntos
Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Bibliotecas de Moléculas Pequenas/química , Regulação Alostérica , Naftalenossulfonato de Anilina/química , Sítios de Ligação , Cristalografia por Raios X , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Ligantes , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-35854710

RESUMO

Introduction: Statistical analysis programs require coding experience and a basic understanding of programming, skills which are not taught as part of medical school or residency curricula. Methods: We conducted a five-day course for early-career Nigerian physician-scientists interested in learning common statistical tests and acquiring R programming skills. The workshop included didactic presentations, small group learning activities, and interactive discussions. A baseline questionnaire captured participant demographics and solicited participants' level of confidence in understanding/performing common statistical tests. REDCap questionnaires were emailed to obtain feedback on educational format and content. A post-workshop assessment covered participants' overall impression of the program. Results: A total of 23 participants attended the program. Most participants were male (n=14, 60.9%) and at an early stage in their career (assistant professor, n=20, 87.0%). Approximately 70% of respondents indicated having received some prior training in statistics. The proportion of participants without experience using R and SAS software (90% and 85%, respectively) was greater than the corresponding proportions for Stata (55%) and SPSS (20%). Prior to the workshop, most respondents expressed being "not at all confident" in performing one-way ANOVA (60%), logistic regression (68%), simple linear regression (60%), and McNemar's test (80%). There was a statistically significant post-workshop improvement in the level of confidence in understanding and performing common statistical tests. The course was rated on a 0-100 scale as "moderately difficult" (mean ± SD: 51.7 ± 19.5). Most participants felt comfortable in putting the knowledge learned into practice (82.2 ± 17.1). Conclusion and Public Health Implications: Introductory R can be taught to junior physician-scientists in resource-limited settings and can inform the development and implementation of similar training initiatives in analogous settings.

18.
J Contin Educ Health Prof ; 42(1): e106-e110, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34459441

RESUMO

INTRODUCTION: Few structured mentoring programs target early-stage investigators in Africa, creating a gap in mentorship skills where HIV burden is greatest. We describe findings from a Nigeria-based workshop for early-career physician scientists to build mentoring and leadership capacity in HIV and noncommunicable disease research. METHODS: Baseline surveys captured participant demographics, confidence in implementing mentoring competencies, and perceived importance of workshop training domains. The workshop included didactic presentations, small group activities, and interactive discussions. Daily surveys evaluated sessions, and postworkshop surveys solicited overall course impressions. RESULTS: Of the 33 participants, most were male (n = 21, 63.6%) and from medicine, laboratory sciences, and surgical specialties. "Building mentees' confidence" and "setting mentees' research goals" were ranked as areas where participants most believed they needed training. Sessions were rated favorably across five areas. Greatest improvements in mean scores were for confidence in identifying personal temperament styles, describing mentoring and leadership theories/frameworks, and developing mentoring plans. Additional identified workshop strengths were content relevance, leadership case series, interactive nature, and collegial atmosphere. All respondents indicated learning something new/useful/helpful in each session. At 6-month postworkshop, most respondents (25 of 26, 96%) had replicated or plan to replicate parts of the workshop in their departments/institutions. DISCUSSION: Effective mentoring training initiatives targeting future academic leaders have the potential to create skilled academicians who can impart mentoring skills and competencies to their mentees.


Assuntos
Infecções por HIV , Tutoria , Doenças não Transmissíveis , Fortalecimento Institucional , Feminino , Infecções por HIV/terapia , Humanos , Liderança , Masculino , Mentores
19.
Am J Trop Med Hyg ; 106(2): 419-423, 2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34814108

RESUMO

Training the next generation of global health researchers is vital for sustainable research partnerships and global health equity. The Fogarty International Center (National Institutes of Health) supports postdoctoral fellows and professional/graduate students in long-term, hands-on mentored research in low- and middle-income countries (LMICs). We surveyed 627 alumni (58% from the United States, 42% from LMICs) from three sequential Fogarty-sponsored global health research training programs (response rate: N = 257, 41%). Publications in the Index Medicus were used to ascertain scholarly output. Most alumni (63%) reported remaining engaged in LMICs and/or worked in academic/research careers (70%). Since completing their Fogarty fellowship, 144 alumni (56%) had received 438 new grants as principal investigator (PI), co-/multi-PI, or site PI. The 257 responding alumni had 5,318 publications during and since their Fogarty fellowships; 2,083 (39%) listed the Fogarty trainee as the first or senior author. These global health training programs highlight the value of LMIC research experience in nurturing the global health research workforce.


Assuntos
Bolsas de Estudo , Saúde Global/educação , Saúde Global/normas , Bolsas de Estudo/estatística & dados numéricos , Feminino , Pesquisa sobre Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino
20.
Artigo em Inglês | MEDLINE | ID: mdl-34660911

RESUMO

The increasing volume and complexity of research activities in Nigeria necessitates urgent measures to improve research infrastructure in grants administration and management. The Vanderbilt-Nigeria Research Administration and Management Training Program (V-RAMP) seeks to build infrastructure capacity in research administration and management and research ethics at a major teaching hospital in Nigeria. We will perform a mixed methods needs assessment of the administrative and management environment and develop an action plan to address infrastructure needs, prioritize processes, and guide program implementation. We will capacitate a newly established Office of Research Administration and improve the knowledge and skills of research administrators and grant managers via short term in-person trainings in Nashville, Tennessee and in Kano, Nigeria and through remote learning opportunities. We will enhance local administrative efficiency and performance of research ethics operations through training and mentoring of members and staff of the ethics review committee. Systematic processes to streamline protocols, including a REDCap protocol tracking database and standard operating procedures in the responsible conduct of research and rigor and reproducibility will also be developed. V-RAMP will enable the creation of a high-quality research administration environment that is knowledgeable, efficient, and compliant regarding the fiscal, management and ethical standards of sponsored research.

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