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1.
LGBT Health ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722241

RESUMO

Purpose: This study examined the utilization of gender-affirming health care by active-duty service members during the initial 5½ years that transgender and gender-diverse (TGD) individuals were authorized to serve in the U.S. military. The aim of this study was to inform policy discussions regarding inclusion of TGD individuals in the military. Methods: We conducted a retrospective cohort study using administrative health care data from the Military Data Repository (MDR). We assessed the association of demographic factors with the utilization of gender-affirming medical and surgical care. We calculated the incidence rate of initial TGD-related encounters and new prescriptions for gender-affirming hormones among Defense Department Service members between July 2016 and December 2021. Results: We identified 2481 service members with an initial health care encounter with an associated TGD-related diagnosis. More than half (53%) of these service members started gender-affirming hormones, and 14% underwent gender-affirming surgery. Mastectomies and hysterectomies accounted for more than 70% of surgeries. Service members made 3.22 initial encounters with a TGD-related diagnosis per 10,000 service members per year, with an overrepresentation of service members who were designated female in the MDR (8.62), junior enlisted (4.98), and young (4.64). Individuals designated female in the MRD comprised 17% of all service members but accounted for 46% of initial encounters, 51% of new prescriptions, and 73% of surgeries. Conclusion: The study revealed a higher-than-expected number of service members seeking gender-affirming care, particularly among service members designated female in the MDR. Military Health System clinicians provided most of this care, which may mitigate the cost of delivering this essential medical care.

2.
J Aging Soc Policy ; : 1-17, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564337

RESUMO

Older adults are more frequently wanting to age in place. Governments are seeking cost-effective and efficient methods of supporting aging populations. Older adults who want to stay in their homes for as long as possible encounter multiple barriers, including struggling to maintain their homes, inadequate levels of social and healthcare support, and the lack of financial capacity to pay for home support services. The Mobile Seniors' Wellness Network (MSWN), a multi-disciplinary and person-centered mobile health and social support intervention study was designed to investigate and support aging in place for older adults living in rural New Brunswick, Canada. Secondary analysis of case notes and exit interviews using content analysis revealed concerns with the lack of affordable and mobile care services for vulnerable rural older adults. Older adults revealed that their needs include "the little things" rather than grand gestures or sweeping policies to age in place such as assistance with grounds and home maintenance, in addition to relational and person-centered health and social care in the home. Reliance on private service delivery and volunteer organizations can increase the likelihood that older adults will experience a breakdown of social support networks tied together loosely by friends, family, and their communities. When services are unattainable aging in place becomes an unreachable goal.

3.
Mil Med ; 189(1-2): e227-e234, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-37542725

RESUMO

BACKGROUND: Pregnancy is the second most common cause of limited duty days among active duty service members in the U.S. Military. Pregnancy accounts for 10% of all days on restricted duty, despite impacting a minority of active duty service members. One out of five service women will experience an unintended pregnancy every year despite the availability of no-cost contraception and reproductive healthcare. Young, single, junior enlisted service women experience the highest rate of unintentional pregnancy. Previous studies have demonstrated service branch-based variability in selection, initiation, and continuation of specific contraceptive methods related to service branch culture and access to contraception during basic training. It is unclear if these differences impact overall contraception use or fertility rates among junior enlisted service women in their first term of enlistment. This study examines rates of contraceptive selection, initiation, continuation, and efficacy among junior enlisted service women in their first 4-year enlistment period, and the service branch specific variability in these outcomes. METHODS: This study is a secondary analysis of Military Healthcare Data Repository records from women who began basic training between 2012 and 2020 and remained on active duty for at least 12 months. We used Kaplan-Meier analyses to examine the effect of age and military branch on contraceptive continuation and efficacy. We used binomial regression for interval censored data, to assess the association of service branch with rates of contraceptive initiation, contraception use, births, and childbirth-related duty restrictions. RESULTS: We identified 147,594 women who began basic training between 2012 and 2020. The mean age of these women at the beginning of basic training was 20.4 ± 3.1 years. Women in the marines and navy had higher contraceptive initiation rates than women in the army or air force. Among women initiating a contraceptive pill, patch, or ring (short-acting reversible contraception), 58.3% were still using some form of hormonal contraception 3 months later. Among women initiating depot-medroxyprogesterone (DMPA), 38.8% were still using any form of hormonal contraception 14 weeks later. Long-acting reversible contraceptive methods, such as intrauterine or subdermal contraceptives, had higher continuation rates and less service-based variability in continuation and failure rates than short-acting reversible contraception or depot-medroxyprogesterone. The proportion of days on any form of prescription contraception during the first 4 years on active duty varied from 23.3% in the army to 38.6% in the navy. The birth rate varied from 34.8 births/1,000 woman-years in the air force up to 62.7 births/1,000 woman-years in the army. Compared with women in the air force, women in the army experienced 2,191 additional days of postpartum leave and 13,908 days on deployment restrictions per 1,000 woman-years. DISCUSSION: Service branch specific variability in contraceptive use is associated with differences in days of pregnancy-related duty restrictions during first 4 years on active duty among junior enlisted females. Robust implementation of best practices in contraceptive care across the military health system to improve contraceptive initiation and continuation appears to offer an opportunity to improve military readiness and promote the health and well-being of active duty service women, particularly in the army.


Assuntos
Anticoncepção , Dispositivos Intrauterinos , Gravidez , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Anticoncepção/métodos , Gravidez não Planejada , Anticoncepcionais , Medroxiprogesterona
4.
Contraception ; 128: 110295, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37739301

RESUMO

OBJECTIVES: Determine if the replacement of patient-initiated, individual contraceptive education with mandatory group contraceptive education, during US Navy basic training, was associated with decreased LARC continuation. STUDY DESIGN: Secondary analysis of administrative billing data from female military recruits who began basic training between September 2012 and February 2020. RESULTS: Servicewomen who started LARC method during rather than after basic training had higher continuation rates. Servicewomen who started training before the implementation of mandatory group education had higher IUD continuation than those trained after. CONCLUSIONS: Implementation of mandatory group contraceptive education during basic training was not associated with a decline in LARC continuation.


Assuntos
Anticoncepcionais Femininos , Militares , Feminino , Humanos , Anticoncepção/métodos , Dispositivos Anticoncepcionais , Comportamento Contraceptivo
5.
Lancet Reg Health Am ; 23: 100529, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37408953

RESUMO

Background: Quitting smoking is especially challenging for low-income smokers due to high stress, high smoking prevalence around them, and limited support for quitting. This study aimed to determine whether any of three interventions designed specifically for low-income smokers would be more effective than standard tobacco quitline services: a specialized quitline, the specialized quitline with social needs navigation, or the standard quitline with social needs navigation. Methods: Using a randomized 2 × 2 factorial design, low-income daily cigarette smokers (n = 1944) in Missouri, USA who called a helpline seeking assistance with food, rent or other social needs were assigned to receive Standard Quitline alone (n = 485), Standard Quitline + Social Needs Navigation (n = 484), Specialized Quitline alone (n = 485), or Specialized Quitline + Social Needs Navigation (n = 490). The target sample size was 2000, 500 per group. The main outcome was 7-day self-reported point prevalence abstinence at 6-month follow-up. Multiple imputation was used to impute outcomes for those missing data at 6-month follow-up. Binary logistic regression analyses were used to assess differences between study groups. Findings: Participants were recruited from June 2017 to November 2020; most were African American (1111 [58%]) or White (666 [35%]), female (1396 [72%]), and reported <$10,000 (957 [51%]) or <$20,000 (1529 [82%]) annual pre-tax household income. At 6-month follow-up (58% retention), 101 participants in the Standard Quitline group reported 7-day point prevalence abstinence (20.8% of those assigned at baseline, 38.1% after imputation). Quit rates in the Specialized Quitline (90 quitters, 18.6%, 38.1%) and Specialized Quitline + Social Needs Navigation (103 quitters, 21.0%, 39.8%) were not different from the Standard Quitline. Quit rates for Standard Quitline + Social Needs Navigation (74 quitters, 15.3%, 30.1%) were significantly lower than Standard Quitline (OR = 0.70, 95% CI = 0.50-0.98). Interpretation: A specialized version of a state tobacco quitline was no more effective than standard quitline services in helping low-income smokers quit. Adding social needs navigation to a standard quitline decreased its effectiveness. Trial registration: ClinicalTrials.gov Identifier: NCT03194958. Funding: National Cancer Institute: R01CA201429.

6.
Child Obes ; 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37389851

RESUMO

Background: Transgender/gender diverse (TGD) youth are at risk for weight-related problems. We describe factors associated with their body mass index (BMI) category. Methods: Chart review of 228 TGD patients, 12-20 years (u = 15.7, standard deviation 1.3), 72% female assigned at birth. BMI percentile was calculated using CDC growth charts. We examined bivariate relationships of 18 clinically derived factors, utilizing analysis of variance (ANOVA) for continuous variables and chi-squared/Fisher's exact test for categorical variables. Nonparametric Classification and Regression Tree (CART) analyses were used to predict BMI category. Results: Almost half (49.6%) of TGD youth presenting for their initial visit for pediatric gender-affirming care fell in the healthy weight range, 4.4% in the underweight range, 16.7% in the overweight range, and 29.4% in the obese range. Self-described weight, weight management intentions, unhealthy weight management, prescription of psychiatric medications, and medications associated with weight gain were associated with BMI category. Use of psychiatric medications (54.8%) and medications associated with weight gain (39.5%) was associated with BMI in the overweight/obese categories. Youth with obesity most often reported unhealthy weight management. In CART models, self-described weight was the strongest predictor of BMI category. Conclusion: TGD youth have high rates of underweight and overweight/obesity. Unhealthy BMI should be treated as part of gender-affirming care. Self-described body weight is associated with weight category. More than half of TGD youth were prescribed psychiatric medications; those with overweight and obesity were more likely prescribed psychiatric and medications with associated weight gain. Youth with obesity were most likely to use unhealthy weight management.

8.
JAMA Netw Open ; 5(11): e2239758, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36318207

RESUMO

Importance: Gonadotropin-releasing hormone analogue (GnRHa) use during puberty improves mental health among transgender and gender-diverse (TGD) adolescents. In previous studies, most (96.5%-98.1%) TGD adolescents who started GnRHa subsequently started gender-affirming hormones (GAH), raising concerns that GnRHa use promotes later use of GAH. Objective: To determine whether GnRHa use among TGD adolescents is associated with increased subsequent GAH use. Design, Setting, and Participants: This is a retrospective cohort study of administrative records collected between 2009 and 2018. The current analysis was completed in August 2022. Participants were enrolled in the US Military Healthcare System (MHS) with an initial TGD-related encounter occurring between ages 10 and 17 years. Exposures: GnRHa use. Main Outcomes and Measures: Initiation of GAH. Results: The 434 patients were a mean (SD) of 15.4 (1.6) years old at the time of their first TGD-related encounter; 312 (71.9%) were assigned female at birth, and 300 (69.1%) had an enlisted insurance sponsor. GnRHa use was more common among patients who were assigned male at birth (28 patients [23.0%]) than those assigned female (42 patients [13.5%]), but GAH use was not. Socioeconomic status was not associated with GnRHa or GAH use. Compared with older patients (aged 14-17 years), those who were younger (aged 10-13 years) at the time of the initial TGD-related encounter had a higher rate of GnRHa use (32 patients [57.1%] vs 38 patients [10.1%]) and a longer median time to starting GAH. The median interval from the date of the initial encounter to starting GAH decreased over time, from 2.3 years (95% CI, 1.7-2.8 years) between October 2009 and December 2014 to 0.6 years (95% CI, 0.5-0.6 years) between September 2016 and April 2018. Patients who were prescribed GnRHa had a longer median time to starting GAH (1.8 years; 95% CI, 1.1-2.4 years) than patients who were not (1.0 years; 95% CI, 0.8-1.2 years) and were less likely to start GAH during the 6 years after their first TGD-related encounter (hazard ratio, 0.52; 95% CI, 0.37-0.71). Among 54 younger (aged 10-13 years) patients who were not eligible to start GAH at their first encounter, GnRHa use was associated with a longer median time to starting GAH, but age at the first TGD-related visit was not. Conclusions and Relevance: In this cohort study of TGD adolescents, GnRHa use was not associated with increased subsequent GAH use. These findings suggest that clinicians can offer the benefits of GnRHa treatment without concern for increasing rates of future GAH use.


Assuntos
Pessoas Transgênero , Transexualidade , Adolescente , Feminino , Humanos , Masculino , Estudos de Coortes , Hormônio Liberador de Gonadotropina , Estudos Retrospectivos , Pessoas Transgênero/psicologia
10.
J Clin Endocrinol Metab ; 107(9): e3937-e3943, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35452119

RESUMO

INTRODUCTION: Concerns about future regret and treatment discontinuation have led to restricted access to gender-affirming medical treatment for transgender and gender-diverse (TGD) minors in some jurisdictions. However, these concerns are merely speculative because few studies have examined gender-affirming hormone continuation rates among TGD individuals. METHODS: We performed a secondary analysis of 2009 to 2018 medical and pharmacy records from the US Military Healthcare System. We identified TGD patients who were children and spouses of active-duty, retired, or deceased military members using International Classification of Diseases-9/10 codes. We assessed initiation and continuation of gender-affirming hormones using pharmacy records. Kaplan-Meier and Cox proportional hazard analyses estimated continuation rates. RESULTS: The study sample included 627 transmasculine and 325 transfeminine individuals with an average age of 19.2 ±â€…5.3 years. The 4-year gender-affirming hormone continuation rate was 70.2% (95% CI, 63.9-76.5). Transfeminine individuals had a higher continuation rate than transmasculine individuals 81.0% (72.0%-90.0%) vs 64.4% (56.0%-72.8%). People who started hormones as minors had higher continuation rate than people who started as adults 74.4% (66.0%-82.8%) vs 64.4% (56.0%-72.8%). Continuation was not associated with household income or family member type. In Cox regression, both transmasculine gender identity (hazard ratio, 2.40; 95% CI, 1.50-3.86) and starting hormones as an adult (hazard ratio, 1.69; 95% CI, 1.14-2.52) were independently associated with increased discontinuation rates. DISCUSSION: Our results suggest that >70% of TGD individuals who start gender-affirming hormones will continue use beyond 4 years, with higher continuation rates in transfeminine individuals. Patients who start hormones, with their parents' assistance, before age 18 years have higher continuation rates than adults.


Assuntos
Disforia de Gênero , Pessoas Transgênero , Transexualidade , Adolescente , Adulto , Criança , Feminino , Disforia de Gênero/tratamento farmacológico , Disforia de Gênero/epidemiologia , Identidade de Gênero , Hormônios , Humanos , Masculino , Transexualidade/tratamento farmacológico , Transexualidade/epidemiologia , Adulto Jovem
11.
Contemp Clin Trials Commun ; 24: 100857, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34849423

RESUMO

BACKGROUND: Low-income Americans smoke cigarettes at higher rates and quit less than other groups. METHODS: To increase their engagement in and success using evidence-based cessation methods, we tested two interventions using a 2x2 randomized factorial design: (1) telephone navigation to reduce financial strain and address social needs such as food, rent and utility payment; and (2) a specialized tobacco quitline designed for low-income smokers. From June 2017 to November 2020, we enrolled 1,944 low-income smokers in Missouri, USA, recruited through the Missouri 2-1-1 helpline, into the trial. This paper describes recruitment, key characteristics and life circumstances of this high-risk population. RESULTS: After eligibility screening, 1,944 participants completed baseline and were randomized. Participants were racially diverse (58% African American), poor (51% < $10,000 annual pre-tax household income) and many reported less than high school education (30%). They reported a mean of 2.5 unmet social needs, especially childcare and paying bills, had high rates of stress, depressive symptoms and sleep problems, and most were in fair or poor health. There were few differences between these variables, and no differences between tobacco use and cessation variables, across the four study groups and between participants recruited pre and during the COVID-19 pandemic. CONCLUSIONS: Trial recruitment through the 2-1-1 helpline is feasible for reaching a population of low-income smokers. Low-income smokers face myriad daily challenges beyond quitting smoking. Cessation interventions need to account for and address these life circumstances. TRIAL REGISTRATION: Clinicaltrials.gov NCT03194958.

12.
Sci Adv ; 7(46): eabk0271, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34767451

RESUMO

Stem cells are remarkably small. Whether small size is important for stem cell function is unknown. We find that hematopoietic stem cells (HSCs) enlarge under conditions known to decrease stem cell function. This decreased fitness of large HSCs is due to reduced proliferation and was accompanied by altered metabolism. Preventing HSC enlargement or reducing large HSCs in size averts the loss of stem cell potential under conditions causing stem cell exhaustion. Last, we show that murine and human HSCs enlarge during aging. Preventing this age-dependent enlargement improves HSC function. We conclude that small cell size is important for stem cell function in vivo and propose that stem cell enlargement contributes to their functional decline during aging.

13.
Methods Mol Biol ; 2353: 37-50, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34292542

RESUMO

Iron-sulfur (Fe-S) clusters are among the oldest and most versatile cofactors present in all domains of life. Many bacterial and eukaryotic Fe-S proteins have been well-characterized, whereas the archaeal ones are less studied. Fe-S proteins are particularly abundant and play essential roles in methanogenic archaea. Methanococcus maripaludis is a model methanogen with available genetic tools. Here, we describe the techniques for anaerobic cultivation of M. maripaludis with formate, liposome-mediated transformation, expression and anoxic affinity purification of Fe-S proteins, Fe-S cluster reconstitution, and analysis of Fe-S proteins by UV-visible absorption spectroscopy.


Assuntos
Mathanococcus , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas Ferro-Enxofre/genética , Mathanococcus/metabolismo , Enxofre/metabolismo
15.
J Trauma Nurs ; 27(1): 6-12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31895313

RESUMO

The American College of Surgeons Committee on Trauma requires physician-to-physician communication prior to interhospital transfer. This requirement can be difficult to achieve in high-volume trauma centers. This pilot project utilizes trauma advanced practice providers (APPs) as the primary communicator, in lieu of the trauma surgeon, prior to interhospital transfer. The hypothesis suggests that APPs can provide safe recommendations and accurately triage patients for the highest level trauma alert. From January to April 2018, a total of 1,145 patients were transferred to a Level I or Level II trauma center. All interhospital trauma transfers were dispatched through a designated transfer center APP (TCAPP). Descriptive statistics were used to describe the frequency of core TCAPP recommendations, including reversal agents for anticoagulants, antibiotics for open fractures, direct admission criteria, administration of blood products, and triaging to the highest level of trauma activation. TCAPP triage accuracy was analyzed and reported as percentages. Percentages are compared between independent groups using a chi-square test. Prior to implementation of the TCAPP role, provider-to-provider communication occurred in less than 1% of interhospital transfers; TCAPP-to-provider communication occurred 92% of the time (p < .001). During the study period, the TCAPP made 398 care-related recommendations. Three (<1%) TCAPP recommendations were deemed inappropriate. The TCAPP (89.7%) and physician (89.9%) triage accuracy was not significantly different (p = .43). Interhospital transfer communication and recommendations can be performed safely and accurately by a trauma trained APP.


Assuntos
Comunicação , Currículo , Educação Médica Continuada/organização & administração , Transferência de Pacientes/normas , Guias de Prática Clínica como Assunto , Centros de Traumatologia/normas , Ferimentos e Lesões/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transferência de Pacientes/estatística & dados numéricos , Projetos Piloto , Centros de Traumatologia/estatística & dados numéricos , Estados Unidos
16.
NPJ Syst Biol Appl ; 5: 35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31602312

RESUMO

Eukaryotic genetic interaction networks (GINs) are extensively described in the Saccharomyces cerevisiae S288C model using deletion libraries, yet being limited to this one genetic background, not informative to individual drug response. Here we created deletion libraries in three additional genetic backgrounds. Statin response was probed with five queries against four genetic backgrounds. The 20 resultant GINs representing drug-gene and gene-gene interactions were not conserved by functional enrichment, hierarchical clustering, and topology-based community partitioning. An unfolded protein response (UPR) community exhibited genetic background variation including different betweenness genes that were network bottlenecks, and we experimentally validated this UPR community via measurements of the UPR that were differentially activated and regulated in statin-resistant strains relative to the statin-sensitive S288C background. These network analyses by topology and function provide insight into the complexity of drug response influenced by genetic background.


Assuntos
Redes Reguladoras de Genes/genética , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Saccharomyces cerevisiae/genética , Biomarcadores Farmacológicos , Análise por Conglomerados , Resistência a Medicamentos/genética , Resistência a Medicamentos/fisiologia , Epistasia Genética/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/genética , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Modelos Genéticos , Proteínas de Saccharomyces cerevisiae/genética , Resposta a Proteínas não Dobradas/genética , Resposta a Proteínas não Dobradas/fisiologia
17.
Contemp Clin Trials ; 80: 40-47, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30904596

RESUMO

Smoking in the United States follows a clear socioeconomic gradient: low-income Americans smoke more and quit less than those with more education and income. Evidence-based interventions like tobacco quitlines are designed to make effective cessation services available on a population basis to all smokers. However, these interventions do not address many of the unique challenges faced by low-income smokers, including unmet basic needs like food, housing, personal safety and money for necessities that often supersede health needs. Research is needed to maximize the use and effectiveness of tobacco quitlines in low-income populations. This paper details the rationale, design and methods for a 2 × 2 randomized controlled trial currently underway comparing the effects of Standard and Specialized Tobacco Quitlines with and without Basic Needs Navigation on intervention engagement and smoking cessation among low-income smokers. Smokers are recruited from United Way 2-1-1 in Missouri and all participants receive tobacco quitline services from Optum. Quitline and navigation services are provided for 3 months. Participants complete telephone surveys at baseline, 3- and 6-month follow up. The primary study outcome is self-reported 7-day point prevalence abstinence at 6-month follow up. Embedding the study in practice agencies will accelerate dissemination and scalability should our findings demonstrate intervention effectiveness.


Assuntos
Aconselhamento/métodos , Comportamentos Relacionados com a Saúde , Navegação de Pacientes/métodos , Abandono do Hábito de Fumar/métodos , Fumar , Humanos , Pobreza/psicologia , Serviços Preventivos de Saúde/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Comportamento de Redução do Risco , Fumar/epidemiologia , Fumar/psicologia , Fumar/terapia , Fatores Socioeconômicos
18.
Diagnostics (Basel) ; 7(2)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28561776

RESUMO

Mammographic breast density (MBD) has been proven to be an important risk factor for breast cancer and an important determinant of mammographic screening performance. The measurement of density has changed dramatically since its inception. Initial qualitative measurement methods have been found to have limited consistency between readers, and in regards to breast cancer risk. Following the introduction of full-field digital mammography, more sophisticated measurement methodology is now possible. Automated computer-based density measurements can provide consistent, reproducible, and objective results. In this review paper, we describe various methods currently available to assess MBD, and provide a discussion on the clinical utility of such methods for breast cancer screening.

19.
FEMS Yeast Res ; 17(3)2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472279

RESUMO

The genetic basis of variation in drug response was investigated in individual Saccharomyces cerevisiae strains that exhibited different susceptibility to two antifungal agents: benomyl and ketoconazole. Following dose-response screening of 25 strains, 4 were selected on the basis of resistance or sensitivity relative to the standard laboratory strain BY. UWOPS87-2421 and L-1374 were respectively resistant and sensitive to benomyl; DBVPG6044 and Y12 were respectively resistant and sensitive to ketoconazole. We used advanced intercross lines and next generation sequencing-bulk segregant analysis to characterise the quantitative trait loci (QTL) underpinning drug responses after drug selection. Drug response was controlled by multiple QTL, ranging from a minimum of 5 to a maximum of 60 loci, almost all of which were not the primary drug target. For each drug, the resistant and the sensitive strain exhibited a number of shared loci, but also had strain-specific QTL. In our analysis, it was possible to estimate genetic effect of QTL, and a number of those shared between resistant and sensitive strains exhibited variable effect on the response phenotype. Thus, drug responses arise as a result of different genetic architectures, depending on the genetic background of the individual strain in question.


Assuntos
Antifúngicos/farmacologia , Benomilo/farmacologia , Farmacorresistência Fúngica/genética , Cetoconazol/farmacologia , Locos de Características Quantitativas , Saccharomyces cerevisiae/efeitos dos fármacos , Cruzamentos Genéticos , Meios de Cultura/química , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Testes de Sensibilidade Microbiana , Fenótipo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Especificidade da Espécie
20.
Infect Immun ; 85(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28320837

RESUMO

Staphylococcus aureus remains a causative agent for morbidity and mortality worldwide. This is in part a result of antimicrobial resistance, highlighting the need to uncover novel antibiotic targets and to discover new therapeutic agents. In the present study, we explored the possibility that iron-sulfur (Fe-S) cluster synthesis is a viable antimicrobial target. RNA interference studies established that Suf (sulfur mobilization)-dependent Fe-S cluster synthesis is essential in S. aureus We found that sufCDSUB were cotranscribed and that suf transcription was positively influenced by sigma factor B. We characterized an S. aureus strain that contained a transposon inserted in the intergenic space between sufC and sufD (sufD*), resulting in decreased transcription of sufSUB Consistent with the transcriptional data, the sufD* strain had multiple phenotypes associated with impaired Fe-S protein maturation. They included decreased activities of Fe-S cluster-dependent enzymes, decreased growth in media lacking metabolites that require Fe-S proteins for synthesis, and decreased flux through the tricarboxylic acid (TCA) cycle. Decreased Fe-S cluster synthesis resulted in sensitivity to reactive oxygen and reactive nitrogen species, as well as increased DNA damage and impaired DNA repair. The sufD* strain also exhibited perturbed intracellular nonchelated Fe pools. Importantly, the sufD* strain did not exhibit altered exoprotein production or altered biofilm formation, but it was attenuated for survival upon challenge by human polymorphonuclear leukocytes. The results presented are consistent with the hypothesis that Fe-S cluster synthesis is a viable target for antimicrobial development.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Neutrófilos/microbiologia , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade , Proteínas de Bactérias/genética , Humanos , Proteínas Ferro-Enxofre/genética , Oxigênio/metabolismo , RNA Antissenso/análise , Espécies Reativas de Nitrogênio/metabolismo , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Virulência
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