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1.
Cell ; 160(5): 928-939, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25723167

RESUMO

Telomerase is required for long-term telomere maintenance and protection. Using single budding yeast mother cell analyses we found that, even early after telomerase inactivation (ETI), yeast mother cells show transient DNA damage response (DDR) episodes, stochastically altered cell-cycle dynamics, and accelerated mother cell aging. The acceleration of ETI mother cell aging was not explained by increased reactive oxygen species (ROS), Sir protein perturbation, or deprotected telomeres. ETI phenotypes occurred well before the population senescence caused late after telomerase inactivation (LTI). They were morphologically distinct from LTI senescence, were genetically uncoupled from telomere length, and were rescued by elevating dNTP pools. Our combined genetic and single-cell analyses show that, well before critical telomere shortening, telomerase is continuously required to respond to transient DNA replication stress in mother cells and that a lack of telomerase accelerates otherwise normal aging.


Assuntos
Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Telomerase/metabolismo , Ciclo Celular , Cromossomos Fúngicos/metabolismo , Replicação do DNA , Mitocôndrias/metabolismo , Ribonucleosídeo Difosfato Redutase/metabolismo , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Telômero/metabolismo
2.
Mol Cell ; 49(5): 1010-5, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23375499

RESUMO

RNase H2-dependent ribonucleotide excision repair (RER) removes ribonucleotides incorporated during DNA replication. When RER is defective, ribonucleotides in the nascent leading strand of the yeast genome are associated with replication stress and genome instability. Here, we provide evidence that topoisomerase 1 (Top1) initiates an independent form of repair to remove ribonucleotides from genomic DNA. This Top1-dependent process activates the S phase checkpoint. Deleting TOP1 reverses this checkpoint activation and also relieves replication stress and genome instability in RER-defective cells. The results reveal an additional removal pathway for a very common lesion in DNA, and they imply that the "dirty" DNA ends created when Top1 incises ribonucleotides in DNA are responsible for the adverse consequences of ribonucleotides in RNase H2-defective cells.


Assuntos
Reparo do DNA , DNA Topoisomerases Tipo I/metabolismo , DNA Fúngico/metabolismo , Ribonucleotídeos/metabolismo , DNA Topoisomerases Tipo I/genética , Instabilidade Genômica , Ribonuclease H/genética , Ribonuclease H/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
3.
Ann Neurol ; 86(5): 671-682, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31486104

RESUMO

OBJECTIVE: To assess whether biological aging as measured by leukocyte telomere length (LTL) is associated with clinical disability and brain volume loss in multiple sclerosis (MS). METHODS: Adults with MS/clinically isolated syndrome in the University of California, San Francisco EPIC cohort study were included. LTL was measured on DNA samples by quantitative polymerase chain reaction and expressed as telomere to somatic DNA (T/S) ratio. Expanded Disability Status Scale (EDSS) and 3-dimensional T1-weighted brain magnetic resonance imaging were performed at baseline and follow-up. Associations of baseline LTL with cross-sectional and longitudinal outcomes were assessed using simple and mixed effects linear regression models. A subset (n = 46) had LTL measured over time, and we assessed the association of LTL change with EDSS change with mixed effects models. RESULTS: Included were 356 women and 160 men (mean age = 43 years, median disease duration = 6 years, median EDSS = 1.5 [range = 0-7], mean T/S ratio = 0.97 [standard deviation = 0.18]). In baseline analyses adjusted for age, disease duration, and sex, for every 0.2 lower LTL, EDSS was 0.27 higher (95% confidence interval [CI] = 0.13-0.42, p < 0.001) and brain volume was 7.4mm3 lower (95% CI = 0.10-14.7, p = 0.047). In longitudinal adjusted analyses, those with lower baseline LTL had higher EDSS and lower brain volumes over time. In adjusted analysis of the subset, LTL change was associated with EDSS change over 10 years; for every 0.2 LTL decrease, EDSS was 0.34 higher (95% CI = 0.08-0.61, p = 0.012). INTERPRETATION: Shorter telomere length was associated with disability independent of chronological age, suggesting that biological aging may contribute to neurological injury in MS. Targeting aging-related mechanisms is a potential therapeutic strategy against MS progression. ANN NEUROL 2019;86:671-682.


Assuntos
Esclerose Múltipla , Telômero/metabolismo , Adulto , Envelhecimento/fisiologia , Senescência Celular/fisiologia , Estudos de Coortes , Estudos Transversais , Avaliação da Deficiência , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Telômero/patologia , Homeostase do Telômero/fisiologia
4.
Stress ; 23(5): 597-606, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32063089

RESUMO

Dysregulation of the stress response can occur early in life and may be affected by nutrition. Our objective was to evaluate the long-term effect of nutritional supplementation during gestation and early childhood on child cortisol and buccal telomere length (a marker of cellular aging) at 4-6 years of age. We conducted a follow-up study of children born to women who participated in a nutritional supplementation trial in Ghana. In one group, a lipid-based nutrient supplement (LNS) was provided to women during gestation and the first 6 months postpartum and to their infants from age 6 to 18 months. The control groups received either iron and folic acid (IFA) during gestation or multiple micronutrients during gestation and the first 6 months postpartum, with no infant supplementation. At age 4-6 years, we measured hair cortisol, buccal telomere length, and salivary cortisol before and after a stressor. Salivary cortisol was available for 364 children across all three trial arms and hair cortisol and telomere length were available for a subset of children (n = 275 and 278, respectively) from the LNS and IFA groups. Telomere length, salivary cortisol, and hair cortisol did not differ by supplementation group. Overall, these findings suggest that nutritional supplementation given during gestation and early childhood does not have an effect on child stress response or chronic stress in children at 4-6 years. Trial registration: ClinicalTrials.gov Identifier NCT00970866.Lay SummaryThis study addressed a research gap about whether improved nutrition during pregnancy and early childhood impacts telomere length and cortisol in preschool children. There was no difference in child telomere length or cortisol between two trial arms of a nutritional supplementation trial that began during pregnancy. The research outcomes indicate lipid-based nutrient supplements, a relatively new form of supplementation, do not have an effect on markers of stress or cellular aging measured in later childhood.


Assuntos
Hidrocortisona , Telômero , Adolescente , Criança , Pré-Escolar , Suplementos Nutricionais , Feminino , Seguimentos , Gana , Humanos , Lactente , Micronutrientes , Gravidez , Estresse Psicológico
5.
Eur J Neurosci ; 50(3): 2311-2321, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30402987

RESUMO

Identifying key neural substrates in addiction disorders for targeted drug development remains a major challenge for clinical neuroscience. One emerging target is the opioid system, where substance-dependent populations demonstrate prefrontal opioid dysregulation that predicts impulsivity and relapse. This may suggest that disturbances to the prefrontal opioid system could confer a risk for relapse in addiction due to weakened 'top-down' control over impulsive behaviour. Naltrexone is currently licensed for alcohol dependence and is also used clinically for impulse control disorders. Using a go/no-go (GNG) task, we examined the effects of acute naltrexone on the neural correlates of successful motor impulse control in abstinent alcoholics (AUD), abstinent polysubstance-dependent (poly-SUD) individuals and controls during a randomised double blind placebo controlled fMRI study. In the absence of any differences on GNG task performance, the AUD group showed a significantly greater BOLD response compared to the control group in lateral and medial prefrontal regions during both placebo and naltrexone treatments; effects that were positively correlated with alcohol abstinence. There was also a dissociation in the positive modulating effects of naltrexone in the orbitofrontal cortex (OFC) and anterior insula cortex (AIC) of the AUD and poly-SUD groups respectively. Self-reported trait impulsivity in the poly-SUD group also predicted the effect of naltrexone in the AIC. These results suggest that acute naltrexone differentially amplifies neural responses within two distinct regions of a salience network during successful motor impulse control in abstinent AUD and poly-SUD groups, which are predicted by trait impulsivity in the poly-SUD group.


Assuntos
Abstinência de Álcool , Dissuasores de Álcool/uso terapêutico , Alcoolismo/diagnóstico por imagem , Comportamento Impulsivo/fisiologia , Naltrexona/uso terapêutico , Desempenho Psicomotor/fisiologia , Adulto , Dissuasores de Álcool/farmacologia , Alcoolismo/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Comportamento Impulsivo/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Naltrexona/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Adulto Jovem
6.
Addict Biol ; 23(1): 425-436, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28247526

RESUMO

Naltrexone, an opioid receptor antagonist, is commonly used as a relapse prevention medication in alcohol and opiate addiction, but its efficacy and the mechanisms underpinning its clinical usefulness are not well characterized. In the current study, we examined the effects of 50-mg naltrexone compared with placebo on neural network changes associated with substance dependence in 21 alcohol and 36 poly-drug-dependent individuals compared with 36 healthy volunteers. Graph theoretic and network-based statistical analysis of resting-state functional magnetic resonance imaging (MRI) data revealed that alcohol-dependent subjects had reduced functional connectivity of a dispersed network compared with both poly-drug-dependent and healthy subjects. Higher local efficiency was observed in both patient groups, indicating clustered and segregated network topology and information processing. Naltrexone normalized heightened local efficiency of the neural network in alcohol-dependent individuals, to the same levels as healthy volunteers. Naltrexone failed to have an effect on the local efficiency in abstinent poly-substance-dependent individuals. Across groups, local efficiency was associated with substance, but no alcohol exposure implicating local efficiency as a potential premorbid risk factor in alcohol use disorders that can be ameliorated by naltrexone. These findings suggest one possible mechanism for the clinical effects of naltrexone, namely, the amelioration of disrupted network topology.


Assuntos
Dissuasores de Álcool/farmacologia , Alcoolismo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Naltrexona/farmacologia , Adulto , Alcoolismo/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Feminino , Neuroimagem Funcional , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Adulto Jovem
7.
Addict Biol ; 22(6): 1576-1589, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27600363

RESUMO

There is a concerted research effort to investigate brain mechanisms underlying addiction processes that may predicate the development of new compounds for treating addiction. One target is the brain's opioid system, because of its role in the reinforcing effects of substances of abuse. Substance-dependent populations have increased numbers of the mu opioid receptor (MOR) in fronto-striatal regions that predict drug relapse, and demonstrate disturbances in these regions during the processing of non-drug rewards. Naltrexone is currently licensed for alcohol and opiate dependence, and may remediate such disturbances through the blockade of MORs in fronto-striatal reward circuitry. Therefore, we examined the potential acute modulating effects of naltrexone on the anticipation of, and instrumental responding for, non-drug rewards in long-term abstinent alcoholics, alcoholic poly substance-dependent individuals and controls using a monetary incentive delay (MID) task during a randomized double blind placebo controlled functional MRI study. We report that the alcoholic poly substance-dependent group exhibited slower and less accurate instrumental responding compared to alcoholics and controls that was less evident after acute naltrexone treatment. However, naltrexone treatment was unable to remediate disturbances within fronto-striatal regions during reward anticipation and 'missed' rewards in either substance-dependent group. While we have not been able to identify the underlying neural mechanisms for improvement observed with naltrexone in the alcoholic poly-substance dependent group, we can confirm that both substance-dependent groups exhibit substantial neural deficits during an MID task, despite being in long-term abstinence.


Assuntos
Alcoolismo/fisiopatologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/fisiopatologia , Desvalorização pelo Atraso/fisiologia , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Recompensa , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Reino Unido
8.
Am J Obstet Gynecol ; 213(1): 80.e1-80.e5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25659467

RESUMO

OBJECTIVE: The purpose of this study was to estimate the association of uterine rupture and previous incision type, either unknown or low transverse, among women who attempt a trial of labor after 1 previous cesarean delivery. STUDY DESIGN: We conducted a secondary analysis of a prospective multicenter observational study of 15,519 women with term singletons who attempted a trial of labor after 1 previous cesarean delivery. Odds ratios for the association between uterine incision location, either unknown or low transverse, and uterine rupture were estimated with the use of multivariable logistic regression. RESULTS: Between 1999 and 2002, 99 of the 15,519 women (0.64%) who attempted a trial of labor after 1 previous cesarean delivery experienced a uterine rupture. Pregnant women with an unknown scar had lower odds of uterine rupture (adjusted odds ratio, 0.71; 95% confidence interval, 0.37-1.37) compared with women with a known low transverse scar. Other adverse maternal outcomes did not differ between the 2 groups of women. CONCLUSION: Among this cohort, women with an unknown uterine incision who attempted a trial of labor were not at increased risk of uterine rupture compared with women with a known low transverse incision.


Assuntos
Ruptura Uterina/epidemiologia , Útero/patologia , Nascimento Vaginal Após Cesárea/efeitos adversos , Adolescente , Adulto , Cesárea , Cicatriz , Feminino , Humanos , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Ruptura Uterina/etiologia , Adulto Jovem
9.
Addict Biol ; 20(1): 194-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23927455

RESUMO

Loss of control over hedonically motivated actions is a defining component of impulse control disorders, such as drug dependence and the proposed 'food addiction' model of obesity. Devolution from goal-directed to compulsively maintained behaviors is partially attributed to abnormalities in the orbitofrontal cortex, an area critical in reward valuation. In the current study, overlapping reductions in orbitofrontal gray matter volume relating to body mass index were seen in healthy control and cocaine-dependent individuals, as well as in relation to duration of cocaine abuse, providing support for a shared neuropathology between the two conditions potentially related to dysfunctional reward-seeking behavior.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/patologia , Lobo Frontal/patologia , Substância Cinzenta/patologia , Obesidade/patologia , Índice de Massa Corporal , Estudos de Casos e Controles , Humanos , Imageamento por Ressonância Magnética , Tamanho do Órgão , Fatores de Tempo
10.
CNS Spectr ; 19(3): 247-55, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24625759

RESUMO

Distinguishing dependent from recreational drug use can be a surprisingly difficult task, and the current means for identifying substance abuse can be inadequate or even misleading. In subjective self-reports, those who are most at risk may down play their consumption, not admitting to the full extent of their habit, and measures purely of quantity of use rarely capture the true nature of an individual's relationship to the drug, such as a psychological dependence on the substance. This trend is particularly true for heavy stimulant use, which is absent of the physical withdrawal symptoms that can help identify opiate or alcohol dependence. As such, a simple objective measure to help identify substance abuse, particularly in individuals who might not otherwise raise suspicion, would be a valuable tool in both clinical and experimental settings. We propose that the drug-word Stroop task, an objective assessment of attentional bias and distraction to salient drug-related stimuli, would be a valuable tool in helping to make these categorizations. This measure has been shown to correlate with drug craving, as well as to successfully distinguish dependent from recreational stimulant users and to help to predict outcomes in treatment-seeking individuals. Here, we survey prior literature on the drug-word Stroop task and provide a perspective on using the assessment as a potential diagnostic for drug use severity.


Assuntos
Atenção , Viés , Teste de Stroop , Transtornos Relacionados ao Uso de Substâncias , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Sinais (Psicologia) , Humanos , Drogas Ilícitas , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/psicologia , Testes de Associação de Palavras
11.
J Minim Invasive Gynecol ; 21(1): 17-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23706677

RESUMO

The patient presented here delivered at 32 weeks' gestation after expectant management of spontaneous preterm membrane rupture. She had an unusually located placenta accreta at the left cornu that required a hysterectomy for treatment. The type of abnormal placentation and the laparoscopic approach to her surgery were unique features of her care.


Assuntos
Ruptura Prematura de Membranas Fetais/cirurgia , Histerectomia/métodos , Placenta Acreta/cirurgia , Adulto , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Resultado do Tratamento
12.
AIDS ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819840

RESUMO

People living with HIV (PLWH) are at greater risk of developing lung diseases even when they are antiretroviral therapy (ART)-adherent and virally suppressed. The most common pulmonary function abnormality in PLWH is that of impaired d iffusing capacity of the l ungs for c arbon monoxide (DL CO ), which is an independent risk factor for increased mortality in PLWH. Earlier work has identified several plasma biomarkers of inflammation and immune activation to be associated with decreased DL CO . However, the underpinning molecular mechanisms of HIV-associated impaired DL CO are largely unknown. We conducted a pilot study of PLWH with normal DL CO (values greater than or equal to the l ower l imit of n ormal, DL CO ≥LLN) or abnormal DL CO (DL CO

13.
J Neurosurg Spine ; 40(3): 312-323, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039536

RESUMO

OBJECTIVE: Surgery for spinal deformity has the potential to improve pain, disability, function, self-image, and mental health. These surgical procedures carry significant risk and require careful selection, optimization, and risk assessment. Epigenetic clocks are age estimation tools derived by measuring the methylation patterns of specific DNA regions. The study of biological age in the adult deformity population has the potential to shed insight onto the molecular basis of frailty and to improve current risk assessment tools. METHODS: Adult patients who underwent deformity surgery were prospectively enrolled. Preoperative whole blood samples were used to assess epigenetic age and telomere length. DNA methylation patterns were quantified and processed to extract 4 principal component (PC)-based epigenetic age clocks (PC Horvath, PC Hannum, PC PhenoAge, and PC GrimAge) and the instantaneous pace of aging (DunedinPACE). Telomere length was assessed using both quantitative polymerase chain reaction (telomere to single gene [T/S] ratio) and a methylation-based telomere estimator (PC DNAmTL). Patient demographic and surgical data included age, BMI, American Society of Anesthesiologists Physical Status Classification System class, and scores on the Charlson Comorbidity Index, adult spinal deformity frailty index (ASD-FI), Edmonton Frail Scale (EFS), Oswestry Disability Index, and Scoliosis Research Society-22r questionnaire (SRS-22r). Medical or surgical complications within 90 days of surgery were collected. Spearman correlations and beta coefficients (ß) from linear regression, adjusted for BMI and sex, were calculated. RESULTS: Eighty-three patients were enrolled with a mean age of 65 years, and 45 were women (54%). All patients underwent posterior fusion with a mean of 11 levels fused and 33 (40%) 3-column osteotomies were performed. Among the epigenetic clocks adjusted for BMI and sex, DunedinPACE showed a significant association with ASD-FI (ß = 0.041, p = 0.002), EFS (ß = 0.696, p = 0.026), and SRS-22r (ß = 0.174, p = 0.013) scores. PC PhenoAge showed associations with ASD-FI (ß = 0.029, p = 0.028) and SRS-22r (ß = 0.159, p = 0.018) scores. PC GrimAge showed associations with ASD-FI (ß = 0.029, p = 0.037) and SRS-22r (ß = 0.161, p = 0.025) scores. Patients with postoperative complications were noted to have shorter telomere length (T/S 0.790 vs 0.858, p = 0.049), even when the analysis controlled for BMI and sex (OR = 1.71, 95% CI 1.07-2.87, p = 0.031). CONCLUSIONS: Epigenetic clocks showed significant associations with markers of frailty and disability, while patients with postoperative complications had shorter telomere length. These data suggest a potential role for aging biomarkers as components of surgical risk assessment. Integrating biological age into current risk calculators may improve their accuracy and provide valuable information for patients, surgeons, and payers.


Assuntos
Fragilidade , Adulto , Humanos , Feminino , Idoso , Masculino , Fragilidade/genética , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Medição de Risco , Biomarcadores , Envelhecimento/genética , Epigênese Genética/genética
14.
Sci Am ; 319(4): 23, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30273314
15.
J Child Adolesc Subst Abuse ; 22(5): 450-465, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24039384

RESUMO

Girls in the juvenile justice system are known to have high rates of co-occurring childhood abuse, trauma, and substance abuse. Girls with this constellation of problems are at high risk for serious adverse outcomes, including problems with drug dependence and abuse. The relationship between childhood sexual abuse, childhood physical abuse, other types of childhood trauma, and rates of substance use during adolescence were examined for girls in the juvenile justice system. As expected, childhood sexual abuse was significantly related to girls' substance use during adolescence. In contrast to prior research, no link was found between physical abuse, lifetime trauma, and substance use. Limitations and future directions are discussed.

16.
J Child Adolesc Subst Abuse ; 22(5): 407-420, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23908582

RESUMO

Although maternal substance abuse in child welfare populations is a well-documented occurrence, little is known about the onset of these behaviors or the substance abuse histories of these mothers. Descriptive data from a small feasibility trial of mothers referred for substance abuse and child neglect suggest adolescent onset of hard substance use. Age of onset was associated with family history of use. The majority of mothers reported polysubstance abuse starting at an early age and quickly escalating patterns of behavior including IV drug use. Implications for prevention efforts for children of families identified with substance abuse problems are discussed.

17.
J Child Adolesc Subst Abuse ; 22(5): 370-387, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24043921

RESUMO

The present study examined the effects of the Middle School Success intervention (MSS), a program to promote healthy adjustment in foster girls, on their health-risking sexual behavior, using a randomized controlled trial (RCT) design. As hypothesized, girls in the intervention condition (n = 48) showed significantly lower levels of health-risking sexual behavior than did girls in the control condition (n = 52) at 36 months postbaseline. Further path analysis indicated that this intervention effect was fully mediated through its effects on girls' tobacco and marijuana use. Findings highlight the importance of providing preventive intervention services to foster girls during early adolescence.

18.
bioRxiv ; 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37662292

RESUMO

Learning and memory mechanisms are critically involved in drug craving and relapse. Environmental cues paired with repeated drug use acquire incentive value such that exposure to the cues alone can trigger craving and relapse. The amygdala, particularly the lateral amygdala (LA), underlies cue-related learning processes that assign valence to environmental stimuli including drug-paired cues. Evidence suggests that the ventral tegmental area (VTA) dopamine (DA) projection to the LA participates in encoding reinforcing effects that act as a US in conditioned cue reward-seeking as DA released in the amygdala is important for emotional and behavioral functions. Here we used chemogenetics to manipulate these VTA DA inputs to the LA to determine the role of this projection for acquisition of drug-cue associations and reinstatement of drug-seeking. We found inhibiting DA input to the LA during cocaine self-administration slowed acquisition and weakened the ability of the previously cocaine-paired cue to elicit cocaine-seeking. Conversely, exciting the projection during self-administration boosted the salience of the cocaine-paired cue as indicated by enhanced responding during cue-induced reinstatement. Importantly, interfering with DA input to the LA had no impact on the ability of cocaine to elicit a place preference or induce reinstatement in response to a priming cocaine injection. Overall, we show that manipulation of projections underlying DA signaling in the LA may be useful for developing therapeutic interventions for substance use disorders.

19.
Nutrients ; 15(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36678207

RESUMO

We hypothesized that consumption of high-fat (HF) ground beef (24% fat) would not affect plasma concentrations of high-density lipoprotein cholesterol (HDL-C) or low-density lipoprotein (LDL-C), whereas low-fat (LF) ground beef (5% fat) would decrease HDL-C and LDL-C concentrations. In a randomized 2-period crossover, controlled feeding trial, 25 men (mean age and body mass index, 40 years and 31.2) consumed 115-g HF or LF patties, 5/week for 5 weeks with a 4-week washout. The HF treatment increased % energy from fat (p = 0.006) and saturated fat (p = 0.004) and tended (p = 0.060) to depress % energy from carbohydrates. The HF and LF treatments decreased the plasma concentrations of HDL-C (p = 0.001) and LDL-C (p = 0.011). Both ground beef treatments decreased the abundance of HDL3a and increased the abundance of HDL3 (p ≤ 0.003); the LF treatment also decreased the abundance of HDL2b and HDL2a (p ≤ 0.012). The HF and LF treatments decreased the abundance of LDL3 and LDL4 (p ≤ 0.024) and the HF treatment also decreased LDL5 (p = 0.041). Contrary to our hypothesis, the HF treatment decreased plasma HDL-C and LDL-C concentrations despite increased saturated fat intake, and both treatments decreased the abundance of smaller, denser LDL subfractions.


Assuntos
Dieta com Restrição de Gorduras , Ácidos Graxos , Masculino , Animais , Humanos , Bovinos , LDL-Colesterol , HDL-Colesterol , Índice de Massa Corporal , Triglicerídeos , Gorduras na Dieta
20.
J Neurosurg Spine ; 38(3): 331-339, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461827

RESUMO

OBJECTIVE: Risk stratification is a critical element of surgical planning. Early tools were fairly crude, while newer instruments incorporate disease-specific elements and markers of frailty. It is unknown if discrepancies between chronological and cellular age can guide surgical planning or treatment. Telomeres are DNA-protein complexes that serve an important role in protecting genomic DNA. Their shortening is a consequence of aging and environmental exposures, with well-established associations with diseases of aging and mortality. There are compelling data to suggest that telomere length can provide insight toward overall health. The authors sought to determine potential associations between telomere length and postoperative complications. METHODS: Adults undergoing elective surgery for spinal deformity were prospectively enrolled. Telomere length was measured from preoperative whole blood using quantitative polymerase chain reaction and expressed as the ratio of telomere (T) to single-copy gene (S) abundance (T/S ratio), with higher T/S ratios indicating longer telomere length. Demographic and patient data included age, BMI, and results for the following rating scales: the Adult Spinal Deformity Frailty Index (ASD-FI), Oswestry Disability Index (ODI), Scoliosis Research Society-22r (SRS-22r), American Society of Anesthesiology (ASA) classification, and Charlson Comorbidity Index (CCI). Operative and postoperative complication data (medical or surgical within 90 days) were also collected. RESULTS: Forty-three patients were enrolled, including 31 women (53%), with a mean age of 66 years and a mean BMI of 28.5. The mean number of levels fused was 11, with 21 (48.8%) combined anterior-posterior approaches. Twenty-two patients (51.2%) had a medical or surgical complication. Patients with a postoperative complication had a significantly lower T/S ratio (0.712 vs 0.813, p = 0.008), indicating shorter telomere length, despite a mild difference in age compared with patients without a postoperative complication (68 vs 63 years, p = 0.069). Patients with complications also had higher CCI scores than patients without complications (2.3 vs 3.8, p = 0.004). There were no significant differences in sex, BMI, ASD-FI score, ASA class, preoperative ODI and SRS-22r scores, number of levels fused, or use of three-column osteotomies. In a multivariate model including age, frailty, ASA class, use of an anterior-posterior approach, CCI score, and telomere length, the authors found that short telomere length was significantly associated with postoperative complications. Patients whose telomere length fell in the shortest quartile had the highest risk (OR 18.184, p = 0.030). CONCLUSIONS: Short telomere length was associated with an increased risk of postoperative complications despite only a mild difference in chronological age. Increasing comorbidity scores also trended toward significance. Larger prospective studies are needed; however, these data provide a compelling impetus to investigate the role of biological aging as a component of surgical risk stratification.


Assuntos
Fragilidade , Escoliose , Humanos , Adulto , Feminino , Idoso , Pessoa de Meia-Idade , Projetos Piloto , Seguimentos , Escoliose/cirurgia , Complicações Pós-Operatórias , Qualidade de Vida , Estudos Retrospectivos
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