Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Biochem Soc Trans ; 52(1): 111-122, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38174726

RESUMEN

Cells encounter a variety of stresses throughout their lifetimes. Oxidative stress can occur via a myriad of factors, including exposure to chemical toxins or UV light. Importantly, these stressors induce chemical changes (e.g. chemical modifications) to biomolecules, such as RNA. Commonly, guanine is oxidized to form 8-oxo-7,8-hydroxyguanine (8-oxoG) and this modification can disrupt a plethora of cellular processes including messenger RNA translation and stability. Polynucleotide phosphorylase (PNPase), heterogeneous nuclear ribonucleoprotein D (HNRPD/Auf1), poly(C)-binding protein (PCBP1/HNRNP E1), and Y-box binding protein 1 (YB-1) have been identified as four RNA-binding proteins that preferentially bind 8-oxoG-modified RNA over unmodified RNA. All four proteins are native to humans and PNPase is additionally found in bacteria. Additionally, under oxidative stress, cell survival declines in mutants that lack PNPase, Auf1, or PCBP1, suggesting they are critical to the oxidative stress response. This mini-review captures the current understanding of the PNPase, HNRPD/Auf1, PCBP1, and YB-1 proteins and the mechanism that has been outlined so far by which they recognize and interact with 8-oxoG-modified RNAs.


Asunto(s)
Proteínas de Unión al ARN , ARN , Humanos , Proteínas de Unión al ARN/metabolismo , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , ARN Mensajero/metabolismo , Regulación de la Expresión Génica
2.
Aust J Prim Health ; 30(1): NULL, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37667463

RESUMEN

BACKGROUND: The Optimal Care Pathways (OCP) are a framework to promote high-quality and integrated cancer care for all Australians, from prevention through to end-of-life-care. Aboriginal and Torres Strait Islander people experience disproportionate cancer incidence and mortality, but little research has addressed whether cancer care for Aboriginal people meets the standards prescribed by the OCPs. This study aims to consider barriers and facilitators to quality cancer care for Aboriginal people. METHODS: Semi-structured interviews were conducted with 30 health professionals who deliver care to Aboriginal people with cancer in primary care and hospital settings in New South Wales, Australia. Health professionals included Aboriginal Health Workers, nurses, general practitioners, and community workers. Interviews were conducted in 2019-2020 and explored participant perspectives of barriers and facilitators of optimal cancer care, particularly related to prevention, early detection, diagnosis, and treatment for Aboriginal people. Data were qualitatively analysed using framework analysis. RESULTS: In general, participants perceived Aboriginal patients to have good access to preventive care. In terms of early detection and diagnosis, access to primary care, pathology, radiology, and some specialists (e.g. respiratory physicians) was seen as optimal. However, access to hospital-based gastroenterologists for colonoscopy was perceived to be poor due to long wait times. Access to optimal care for cancer treatment was perceived to be hindered due to the lack of bulk-billing for bowel cancer, breast cancer, and cardiothoracic surgery. Other barriers to care identified by participants included unclear referral pathways, poor communication between patient and the treating team, and a lack of timely provision of discharge summaries. CONCLUSIONS: Facilitators of optimal care during treatment and survivorship included: the Integrated Team Care and Close the Gap programs, and presence of key health workers to help patients navigate the health system. The major barriers to quality cancer care for Aboriginal people appeared to be to specialist and procedural access, demonstrating that the 'Inverse Care' law applied in reducing access for populations at higher risk of cancer.


Asunto(s)
Servicios de Salud del Indígena , Neoplasias , Humanos , Australia/epidemiología , Aborigenas Australianos e Isleños del Estrecho de Torres , Vías Clínicas , Neoplasias/diagnóstico , Neoplasias/terapia
3.
Res Dev Disabil ; 136: 104479, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36963311

RESUMEN

BACKGROUND: This early intervention study investigated the effectiveness of a relationship-based, developmental enhancement process for children who were prenatally exposed to alcohol in the South African context. METHODS: Groups were created according to the child's level of risk for alcohol-related developmental issues based on each mother's alcohol use during pregnancy as assessed using the Alcohol Use Disorders Identification Test (AUDIT). Primary caregiver/child dyads were the focus of the intervention and child development was monitored by the Ages and Stages Questionnaire (ASQ). Eighteen caregiver/child dyads were in the heavily alcohol-exposed group, and 20 caregiver/child dyads were in the no or light alcohol-exposure group. The Home Observation Measurement of the Environment (HOME) was measured pre and post intervention. RESULTS: The results indicated significant improvements in the home environment (p < .001) post-intervention for the entire cohort. For the total HOME score, there was a statistically significant main effect for time (pre- vs post-test), F(1, 36)= 65.205, p < .001, partial η2 = .64. with 99% confidence limits from .35 to .78. The offspring and parents from both the heavy alcohol exposure group and the no/low alcohol exposure group benefitted from the intervention over the duration of the intervention. Of the HOME domains affected, responsivity was the most improved in the households. The children's scores on the ASQ varied substantially over the months of the intervention, and the offspring of the heavy exposure group often performed significantly worse than the no/low exposure group. Nevertheless, further analysis revealed that children with the lowest performance at baseline improved their performance on most ASQ domains throughout the intervention and performed significantly better on all ASQ domains over time and at completion of the intervention. CONCLUSIONS: This relationship-based, early intervention program for children resulted in benefits to all of the children over time.


Asunto(s)
Alcoholismo , Trastornos del Espectro Alcohólico Fetal , Embarazo , Femenino , Humanos , Niño , Sudáfrica , Desarrollo Infantil , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/prevención & control , Etanol , Trastornos del Espectro Alcohólico Fetal/prevención & control
4.
Nanomaterials (Basel) ; 12(24)2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36558285

RESUMEN

Recently, the abnormal level of zinc emerged as a powerful indicator or risk factor for metabolic, endocrine, neurodegenerative and cardiovascular diseases, including cancer. Electrochemical detection has been explored to quantify zinc in a precise, rapid, and non-expensive way; however, most of the current electrochemical systems lack in specificity. In this work we studied a highly selective and sensitive electrochemical method to detect quickly and reliably free zinc ions (Zn2+). The surface of the working electrode was modified with zincon electropolymerized on carbon nanotube (CNT) to enable the binding of zinc in complex body fluids. After being physicochemically characterized, the performances of the zincon-CNT complex was electrochemically assessed. Square Wave Voltammetry (SWV) was used to determine the calibration curve and the linear range of zinc quantification in artificial saliva and urine. This zincon- CNT system could specifically quantify mobile Zn2+ in salivary and urinary matrices with a sensitivity of ~100 ng·mL-1 and a limit of detection (LOD) of ~20 ng·mL-1. Zincon-modified CNT presented as a desirable candidate for the detection and quantification of free zinc in easily body fluids that potentially can become a diagnostic non-invasive testing platform.

5.
Bone ; 162: 116478, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35779845

RESUMEN

Postmenopausal osteoporosis (PMOP) therapies are frequently evaluated by bone mineral density (BMD) gains against patients receiving placebo (calcium and vitamin D supplementation, a mild bone turnover-suppressing intervention), which is not equivalent to either healthy or treatment-naive PMOP. The aim of the present observational study was to assess the effects of TPTD treatment in PMOP (20 µg, once daily) at 6 (TPTD 6m; n = 28, age 65 ± 7.3 years), and 24 (TPTD 24m; n = 32, age 67.4 ± 6.15 years) months on bone quality indices at actively forming trabecular surfaces (with fluorescent double labels). Data from the TPTD-treated PMOP patients were compared with those in healthy adult premenopausal women (HC; n = 62, age 40.5 ± 10.6 years), and PMOP receiving placebo (PMOP-PLC; n = 94, age 70.6 ± 4.5 years). Iliac crest biopsies were analyzed by Raman microspectroscopy at three distinct tissue ages: mid-distance between the second label and the bone surface, mid-distance between the two labels, and 1 µm behind the first label. Mineral to matrix ratio (MM), mineral maturity/crystallinity (MMC), tissue water (TW), glycosaminoglycan (GAGs), and pyridinoline (Pyd) content were determined. Outcomes were compared by ANCOVA with subject age and tissue age as covariates, and health status as a fixed factor, followed by Sidak's post-hoc testing (significance assigned to p < 0.05). Both TPTD groups increased MM compared to PMOP-PLC. While TPTD 6m had values similar to HC, TPTD 24m had higher values compared to either HC or TPTD 6m. Both TPTD groups had lower MMC values compared to PMOP-PLC and similar to HC. TPTD 6m patients had higher TW content compared to HC, while TPTD 24m had values similar to HC and lower than either PMOP-PLC or TPTD 6m. Both TPTD groups had lower GAG content compared to HC group, while TPTD 6m had higher values compared to PMOP-PLC. Finally, TPTD 6m patients had higher Pyd content compared to HC and lower compared to PMOP-PLC, while TPTD 24m had lower values compared to PMOP-PLC and TPTD 6m, and similar to HC group. The results of the present study indicate that effects of TPTD on forming trabecular bone quality indices depend on treatment duration. At the recommended length of 24 m, TPTD restores bone mineral and organic matrix quality indices (MMC, TW, Pyd content) to premenopausal healthy (HC) levels.


Asunto(s)
Conservadores de la Densidad Ósea , Osteoporosis Posmenopáusica , Adulto , Anciano , Densidad Ósea , Conservadores de la Densidad Ósea/farmacología , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Humanos , Ilion/patología , Persona de Mediana Edad , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/patología , Teriparatido/farmacología , Teriparatido/uso terapéutico
6.
Nanotechnology ; 33(10)2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34808600

RESUMEN

We demonstrate a bottom-up process for programming the deposition of coaxial thin films aligned to the underlying dopant profile of semiconductor nanowires. Our process synergistically combines three distinct methods-vapor-liquid-solid nanowire growth, selective coaxial lithography via etching of surfaces (SCALES), and area-selective atomic layer deposition (AS-ALD)-into a cohesive whole. Here, we study ZrO2on Si nanowires as a model system. Si nanowires are first grown with an axially modulated n-Si/i-Si dopant profile. SCALES then yields coaxial poly(methyl methacrylate) (PMMA) masks on the n-Si regions. Subsequent AS-ALD of ZrO2occurs on the exposed i-Si regions and not on those masked by PMMA. We show the spatial relationship between nanowire dopant profile, PMMA masks, and ZrO2films, confirming the programmability of the process. The nanoscale resolution of our process coupled with the plethora of available AS-ALD chemistries promises a range of future opportunities to generate structurally complex nanoscale materials and electronic devices using entirely bottom-up methods.

7.
Int J Law Psychiatry ; 78: 101736, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34450485

RESUMEN

Scottish mental health legislation includes a unique criterion for the use of compulsion in the delivery of mental health care and treatment. Under the Mental Health (Care and Treatment) (Scotland) Act, 2003, patients must exhibit 'significantly impaired decision-making ability' (SIDMA) in order to be eligible for psychiatric detention or involuntary psychiatric treatment outside the forensic context. The SIDMA requirement represents a distinctive strategy in ongoing international efforts to rethink the conditions under which psychiatric compulsion is permissible. We reconstruct the history of the Scottish SIDMA requirement, analyse its differences from so-called 'fusion law,' and then examine how the SIDMA standard actually functions in practice. We analyse 100 reports that accompany applications for Compulsory Treatment Orders (CTOs). Based on this analysis, we provide a profile of the patient population that is found to exhibit SIDMA, identify the grounds upon which SIDMA is attributed to individual patients, and offer an assessment of the quality of the documentation of SIDMA. We demonstrate that there are systemic areas of poor practice in the reporting of SIDMA, with only 12% of CTOs satisfying the minimum standard of formal completeness endorsed by the Mental Welfare Commission. We consider what lessons might be drawn both for the ongoing review of mental health legislation in Scotland, and for law reform initiatives in other jurisdictions.


Asunto(s)
Tratamiento Involuntario , Trastornos Mentales , Humanos , Trastornos Mentales/terapia , Salud Mental , Escocia
8.
Bone ; 145: 115848, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33453443

RESUMEN

The ability of bone to resist fracture is dependent on the composite nature of its mineral and organic matrix content. Teriparatide (TPTD) and zoledronic acid (ZOL) are approved anabolic and antiresorptive therapies, respectively, to reduce fracture risk in women with postmenopausal osteoporosis. In the SHOTZ study, postmenopausal women with osteoporosis were treated with TPTD (20 µg daily, subcutaneous) or ZOL (5 mg/year, intravenous infusion) for 24 months. Iliac crest biopsies were obtained at 6 months and again at 24 months from approximately one third of the original study cohort. To investigate the early effects of these two drugs on the quality of newly formed bone, we used vibrational spectroscopic techniques to analyze tetracycline-labelled transiliac biopsies obtained from participants at the 6-month time point. Raman spectra were acquired at forming trabecular and intra-cortical surfaces (identified by fluorescent double labels), to determine mineral, organic matrix, glycosaminoglycan, and tissue water content, as well as mineral maturity/crystallinity at three specific tissue ages (1-5, 15, and ≥25 days). Fourier transformed infrared microspectroscopy was used to determine pyridinoline/divalent collagen cross-link ratios. At 6 months, treatment with TPTD versus ZOL resulted in lower mineral and higher organic matrix content, increased tissue water content, and lower mineral/matrix, mineral maturity/crystallinity, glycosaminoglycan content, and pyridinoline/divalent enzymatic collagen cross-link ratio. Our results suggest that TPTD and ZOL have differential effects on material properties of newly formed bone at individual remodeling sites, highlighting their different mechanisms of action.


Asunto(s)
Conservadores de la Densidad Ósea , Osteoporosis Posmenopáusica , Densidad Ósea , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Humanos , Minerales , Osteoporosis Posmenopáusica/tratamiento farmacológico , Posmenopausia , Teriparatido/farmacología , Ácido Zoledrónico
9.
J Exp Psychol Anim Learn Cogn ; 45(3): 280-289, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31021132

RESUMEN

Animals optimize their behavior to maximize rewards by utilizing cues from the environment. In discrimination learning, cues signal when rewards can and cannot be earned by making a particular response. In our experiment, we trained male mice to press a lever to receive a reward on a random interval schedule. We then introduced a prolonged tone (20, 40, or 80 sec), during which no rewards could be earned. We sought to test our hypothesis that the duration of the tone and frequency of reward during the inter-tone-intervals affect the informativeness of cues and led to differences in discriminative behavior. Learning was expressed as an increase in lever pressing during the intertrial interval (ITI) and, when the informativeness of the cue was high, animals also reduced their lever pressing during the tone. Additionally, we found that the depth of discriminative learning was linearly related to the informativeness of the cues. Our results show that the time-scale invariant information-theoretic definition of contingency applied to excitatory conditioning can also be applied to inhibitory conditioning. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Condicionamiento Operante/fisiología , Aprendizaje Discriminativo/fisiología , Estimulación Acústica , Animales , Conducta Animal/fisiología , Señales (Psicología) , Masculino , Ratones , Recompensa , Factores de Tiempo
10.
J Bone Joint Surg Am ; 100(21): 1819-1828, 2018 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-30399076

RESUMEN

BACKGROUND: Osteoporosis is prevalent in the United States, with an increasing need for management. In this study, we evaluated the effectiveness of a private orthopaedic practice-based osteoporosis management service (OP MS) in reducing subsequent fracture risk and improving other aspects of osteoporosis management of patients who had sustained fractures. METHODS: This was a retrospective cohort study using the 100% Medicare data set for Michigan residents with any vertebral; hip, pelvic or femoral; or other nonvertebral fracture during the period of April 1, 2010 to September 30, 2014. Patients who received OP MS care with a follow-up visit within 90 days of the first fracture, and those who did not seek OP MS care but had a physician visit within 90 days of the first fracture, were considered as exposed and unexposed, respectively (first follow-up visit = index date). Eligible patients with continuous enrollment in Medicare Parts A and B for the 90-day pre-index period were followed until the earliest of death, health-plan disenrollment, or study end (December 31, 2014) to evaluate rates of subsequent fracture, osteoporosis medication prescriptions filled, and bone mineral density (BMD) assessments. Health-care costs were evaluated among patients with 12 months of post-index continuous enrollment. Propensity-score matching was used to balance differences in baseline characteristics. Each exposed patient was matched to an unexposed patient within ± 0.01 units of the propensity score. After propensity-score matching, Cox regression examined the hazard ratio (HR) of clinical and economic outcomes in the exposed and unexposed cohorts. RESULTS: Two well-matched cohorts of 1,304 patients each were produced. The exposed cohort had a longer median time to subsequent fracture (998 compared with 743 days; log-rank p = 0.001), a lower risk of subsequent fracture (HR = 0.8; 95% confidence interval [CI] = 0.7 to 0.9), and a higher likelihood of having osteoporosis medication prescriptions filled (HR = 1.7; 95% CI = 1.4 to 2.0) and BMD assessments (HR = 4.3; 95% CI = 3.7 to 5.0). The total 12-month costs ($25,306 compared with $22,896 [USD]; p = 0.082) did not differ significantly between the cohorts. CONCLUSIONS: A private orthopaedic practice-based OP MS effectively reduced subsequent fracture risk, likely through coordinated and ongoing comprehensive patient care, without a significant overall higher cost. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Costos de la Atención en Salud , Ortopedia , Osteoporosis/terapia , Fracturas Osteoporóticas/prevención & control , Práctica Privada , Anciano , Anciano de 80 o más Años , Densidad Ósea , Conservadores de la Densidad Ósea/uso terapéutico , Costo de Enfermedad , Femenino , Humanos , Masculino , Michigan , Persona de Mediana Edad , Osteoporosis/complicaciones , Osteoporosis/economía , Fracturas Osteoporóticas/etiología , Estudios Retrospectivos
11.
Oper Neurosurg (Hagerstown) ; 15(suppl_1): S295-S349, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30260428

RESUMEN

In this supplement, we build on work previously published under the Human Connectome Project. Specifically, we seek to show a comprehensive anatomic atlas of the human cerebrum demonstrating all 180 distinct regions comprising the cerebral cortex. The location, functional connectivity, and structural connectivity of these regions are outlined, and where possible a discussion is included of the functional significance of these areas. In part 7, we specifically address regions relevant to the lateral parietal lobe.


Asunto(s)
Conectoma , Lateralidad Funcional/fisiología , Red Nerviosa/anatomía & histología , Lóbulo Parietal/anatomía & histología , Imagen de Difusión Tensora/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología , Vías Nerviosas/anatomía & histología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Neuroimagen/métodos , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Parietal/fisiología
12.
J Bone Miner Res ; 33(2): 298-306, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29024120

RESUMEN

There has been renewed interest of late in the role of modeling-based formation (MBF) during osteoporosis therapy. Here we describe early effects of an established anabolic (teriparatide) versus antiresorptive (denosumab) agent on remodeling-based formation (RBF), MBF, and overflow MBF (oMBF) in human transiliac bone biopsies. Postmenopausal women with osteoporosis received subcutaneous teriparatide (n = 33, 20 µg/d) or denosumab (n = 36, 60 mg once/6 months), open-label for 6 months at 7 US and Canadian sites. Subjects received double fluorochrome labeling at baseline and before biopsy at 3 months. Sites of bone formation were designated as MBF if the underlying cement line was smooth, RBF if scalloped, and oMBF if formed over smooth cement lines adjacent to scalloped reversal lines. At baseline, mean RBF/bone surface (BS), MBF/BS, and oMBF/BS were similar between the teriparatide and denosumab groups in each bone envelope assessed (cancellous, endocortical, periosteal). All types of formation significantly increased from baseline in the cancellous and endocortical envelopes (differences p < 0.001) with teriparatide (range of changes 2.9- to 21.9-fold), as did MBF in the periosteum (p < 0.001). In contrast, all types of formation were decreased or not significantly changed with denosumab, except MBF/BS in the cancellous envelope, which increased 2.5-fold (difference p = 0.048). These data highlight mechanistic differences between these agents: all 3 types of bone formation increased significantly with teriparatide, whereas formation was predominantly decreased or not significantly changed with denosumab, except for a slight increase in MBF/BS in the cancellous envelope. © 2017 American Society for Bone and Mineral Research.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Denosumab/farmacología , Osteogénesis/efectos de los fármacos , Teriparatido/farmacología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad
13.
J Bone Miner Res ; 33(4): 627-633, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29194749

RESUMEN

Previously, we reported on bone histomorphometry, biochemical markers, and bone mineral density distribution after 6 and 24 months of treatment with teriparatide (TPTD) or zoledronic acid (ZOL) in the SHOTZ study. The study included a 12-month primary study period, with treatment (TPTD 20 µg/d by subcutaneous injection or ZOL 5 mg/yr by intravenous infusion) randomized and double-blind until the month 6 biopsy (TPTD, n = 28; ZOL, n = 30 evaluable), then open-label, with an optional 12-month extension receiving the original treatment. A second biopsy (TPTD, n = 10; ZOL, n = 9) was collected from the contralateral side at month 24. Here we present data on remodeling-based bone formation (RBF), modeling-based bone formation (MBF), and overflow modeling-based bone formation (oMBF, modeling overflow adjacent to RBF sites) in the cancellous, endocortical, and periosteal envelopes. RBF was significantly greater after TPTD versus ZOL in all envelopes at 6 and 24 months, except the periosteal envelope at 24 months. MBF was significantly greater with TPTD in all envelopes at 6 months but not at 24 months. oMBF was significantly greater at 6 months in the cancellous and endocortical envelopes with TPTD, with no significant differences at 24 months. At 6 months, total bone formation surface was also significantly greater in each envelope with TPTD treatment (all p < 0.001). For within-group comparisons from 6 to 24 months, no statistically significant changes were observed in RBF, MBF, or oMBF in any envelope for either the TPTD or ZOL treatment groups. Overall, TPTD treatment was associated with greater bone formation than ZOL. Taken together the data support the view that ZOL is a traditional antiremodeling agent, wheareas TPTD is a proremodeling anabolic agent that increases bone formation, especially that associated with bone remodeling, including related overflow modeling, with substantial modeling-based bone formation early in the course of treatment. © 2017 American Society for Bone and Mineral Research.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Teriparatido/administración & dosificación , Ácido Zoledrónico/administración & dosificación , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Teriparatido/efectos adversos , Ácido Zoledrónico/efectos adversos
14.
Sci Adv ; 3(11): e1701682, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29109977

RESUMEN

Addiction to cocaine is commonly preceded by experiences with legal or decriminalized drugs, such as alcohol, nicotine, and marijuana. The biological mechanisms by which these gateway drugs contribute to cocaine addiction are only beginning to be understood. We report that in the rat, prior alcohol consumption results in enhanced addiction-like behavior to cocaine, including continued cocaine use despite aversive consequences. Conversely, prior cocaine use has no effect on alcohol preference. Long-term, but not short-term, alcohol consumption promotes proteasome-mediated degradation of the nuclear histone deacetylases HDAC4 and HDAC5 in the nucleus accumbens, a brain region critical for reward-based memory. Decreased nuclear HDAC activity results in global H3 acetylation, creating a permissive environment for cocaine-induced gene expression. We also find that selective degradation of HDAC4 and HDAC5, facilitated by the class II-specific HDAC inhibitor MC1568, enhances compulsive cocaine self-administration. These results parallel our previously reported findings that the gateway drug nicotine enhances the behavioral effects of cocaine via HDAC inhibition. Together, our findings suggest a shared mechanism of action for the gateway drugs alcohol and nicotine, and reveal a novel mechanism by which environmental factors may alter the epigenetic landscape of the reward system to increase vulnerability to cocaine addiction.


Asunto(s)
Alcoholes/farmacología , Histona Desacetilasas/metabolismo , Proteolisis/efectos de los fármacos , Animales , Encéfalo/patología , Cocaína/farmacología , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/química , Histonas/metabolismo , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ratas , Ratas Sprague-Dawley , Autoadministración
15.
Pathology ; 49(3): 267-270, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28238415

RESUMEN

Papillary lesions of the breast are most commonly diagnosed via mammographic screening. The standard practice has been to excise these lesions, since a subset of papillary lesions are neoplastic. However, this approach leads to a high proportion of negative excisions. In order to identify papillary lesions which could be managed by surveillance alone, we assessed the outcome of 103 papillary lesions diagnosed on core needle biopsy in a public screening program. Subsequent excision biopsy led to an upgrade to malignancy in 30% of cases. Segregation via presence or absence of atypia stratified the outcome into 72% upgrade, compared with 7% upgrade, respectively. Further, in the latter group (i.e., no atypia on core needle biopsy with 7% upgrade to malignancy), the neoplasia found in the targeted excision area was low to intermediate grade ductal carcinoma in situ only, with no invasive neoplasia (4 cases). Of the lesions identified due to microcalcification, the microcalcification was present within an adjacent benign lesion in 35% of cases and hence the papillary lesion was detected incidentally. Overall therefore, we have identified a cohort of papillary lesions in which conservative management, rather than excision, could be considered, i.e., those without atypia, including those without atypia in which the papillary lesion was found incidental to microcalcification in an adjacent benign lesion.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/diagnóstico , Carcinoma Intraductal no Infiltrante/patología , Adulto , Anciano , Biopsia con Aguja , Calcinosis/diagnóstico , Calcinosis/patología , Carcinoma Ductal de Mama/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Mamografía/métodos , Persona de Mediana Edad , Papiloma/patología
16.
Arthritis Rheumatol ; 68(9): 2122-8, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27111239

RESUMEN

OBJECTIVE: To determine the effect of alendronate (ALN) and teriparatide on trabecular bone score (TBS) in patients with glucocorticoid-induced osteoporosis. METHODS: Patients with chronic glucocorticoid therapy-induced osteoporosis (median 7.5 mg/day prednisone equivalent for ≥90 days) were randomized to receive oral ALN 10 mg/day (n = 214) or subcutaneous teriparatide 20 µg/day (n = 214) for 36 months; 118 patients in the ALN group and 123 patients in the teriparatide group completed treatment. Dual x-ray absorptiometry (DXA) results for 53 patients receiving ALN and 56 patients receiving teriparatide who had DXA scans with adequate resolution to perform TBS analysis and completed 36 months of therapy were blindly analyzed for TBS at baseline and 3, 6, 12, 18, 24, and 36 months. RESULTS: In teriparatide-treated patients, TBS was significantly increased at 18 months compared to baseline, and by 36 months had increased 3.7% (P < 0.05). In ALN-treated patients, there was not a significant change in TBS compared to baseline at any time point. Changes in lumbar spine bone mineral density (BMD) measured by DXA in the subgroup with TBS data were similar to BMD results in the overall study population. At 36 months, increases in lumbar spine BMD were 5.5% and 10.3% in patients treated with ALN and teriparatide, respectively. CONCLUSION: In patients with glucocorticoid-induced osteoporosis, both ALN and teriparatide increased lumbar spine BMD. However, trabecular bone score significantly increased with teriparatide but did not significantly change with ALN. The pathogenesis of glucocorticoid-induced osteoporosis is predominantly reduced bone formation. TBS may represent a sensitive measure to discriminate treatment effects of an anabolic versus an antiresorptive drug in glucocorticoid-induced osteoporosis.


Asunto(s)
Alendronato/uso terapéutico , Hueso Esponjoso/efectos de los fármacos , Glucocorticoides/efectos adversos , Osteoporosis/inducido químicamente , Osteoporosis/tratamiento farmacológico , Prednisona/efectos adversos , Teriparatido/uso terapéutico , Conservadores de la Densidad Ósea , Enfermedad Crónica , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
J Bone Miner Res ; 31(8): 1527-35, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26931279

RESUMEN

The Skeletal Histomorphometry in Patients on Teriparatide or Zoledronic Acid Therapy (SHOTZ) study assessed the progressive effects of teriparatide (TPTD) and zoledronic acid (ZOL) on bone remodeling and material properties in postmenopausal women with osteoporosis. Previously, we reported that biochemical and histomorphometric bone formation indices were significantly higher in patients receiving TPTD versus ZOL. Here we report bone mineralization density distribution (BMDD) results based on quantitative backscattered electron imaging (qBEI). The 12-month primary study was randomized and double blind until the month 6 biopsy, then open label. Patients (TPTD, n = 28; ZOL, n = 31) were then eligible to enter a 12-month open-label extension with their original treatment: TPTD 20 µg/d (subcutaneous injection) or ZOL 5 mg/yr (intravenous infusion). A second biopsy was collected from the contralateral side at month 24 (TPTD, n = 10; ZOL, n = 10). In cancellous bone, ZOL treatment was associated at 6 and 24 months with significantly higher average degree of mineralization (CaMEAN, +2.2%, p = 0.018; +3.9%, p = 0.009, respectively) and with lower percentage of low mineralized areas (CaLOW , -34.6%, p = 0.029; -33.7%, p = 0.025, respectively) and heterogeneity of mineralization CaWIDTH (-12.3%, p = 0.003; -9.9%, p = 0.012, respectively), indicating higher mineralization density and more homogeneous mineral content versus TPTD. Within the ZOL group, significant changes were found in all parameters from month 6 to 24, indicating a progressive increase in mineralization density. In sharp contrast, mineralization density did not increase over time with TPTD, reflecting ongoing deposition of new bone. Similar results were observed in cortical bone. In this study, TPTD stimulated new bone formation, producing a mineralized bone matrix that remained relatively heterogeneous with a stable mean mineral content. ZOL slowed bone turnover and prolonged secondary mineralization, producing a progressively more homogeneous and highly mineralized bone matrix. Although both TPTD and ZOL increase clinical measures of bone mineral density (BMD), this study shows that the underlying mechanisms of the BMD increases are fundamentally different. © 2016 American Society for Bone and Mineral Research.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Calcificación Fisiológica/efectos de los fármacos , Difosfonatos/farmacología , Imidazoles/farmacología , Teriparatido/farmacología , Anciano , Biopsia , Hueso Esponjoso/diagnóstico por imagen , Hueso Esponjoso/efectos de los fármacos , Hueso Esponjoso/patología , Hueso Cortical/diagnóstico por imagen , Hueso Cortical/efectos de los fármacos , Hueso Cortical/patología , Humanos , Persona de Mediana Edad , Ácido Zoledrónico
18.
J Bone Miner Res ; 31(7): 1429-39, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26841258

RESUMEN

Previously, we reported the effects of teriparatide (TPTD) and zoledronic acid (ZOL) on bone formation based on biochemical markers and bone histomorphometry of the cancellous envelope at month 6 in postmenopausal women with osteoporosis who participated in the 12-month primary Skeletal Histomorphometry in Subjects on Teriparatide or Zoledronic Acid Therapy (SHOTZ) study. Patients were eligible to enter a 12-month extension on their original treatment regimen: TPTD 20 µg/day (s.c. injection) or ZOL 5 mg/year (i.v. infusion). A second biopsy was performed at month 24. Here we report longitudinal changes between and within each treatment group in the cancellous, endocortical, intracortical, and periosteal bone envelopes in patients with evaluable biopsies at months 6 and 24 (paired data set: TPTD, n = 10; ZOL, n = 9). Between-group differences are also reported in the larger set of patients with evaluable biopsies at month 6 (TPTD, n = 28; ZOL, n = 30). Data from the cancellous envelope at month 6 or month 24 provided a reference to compare differences across envelopes within each treatment group. The 24-month results extend our earlier report that TPTD and ZOL possess different tissue-level mechanisms of action. Moreover, these differences persisted for at least 2 years in all four bone envelopes. Few longitudinal differences were observed within or across bone envelopes in ZOL-treated patients, suggesting that the low bone formation indices at month 6 persisted to month 24. Conversely, the magnitude of the effect of TPTD on bone formation varied across individual envelopes: median values for mineralizing surface (MS/BS) and bone formation rate (BFR/BS) at month 6 were approximately 3-fold to 5-fold higher in the endocortical and intracortical envelopes compared to the cancellous envelope. Although MS/BS and BFR/BS declined in these envelopes at month 24, median values continued to exceed, or were not significantly different from, those in the cancellous envelope. This study demonstrates for the first time that bone formation indices are higher with TPTD treatment than with ZOL in all four bone envelopes and the difference persists for at least 2 years. Moreover, the magnitude of the effect of TPTD in cortical bone remains robust at 24 months. © 2016 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).


Asunto(s)
Hueso Esponjoso , Difosfonatos/administración & dosificación , Imidazoles/administración & dosificación , Osteoporosis Posmenopáusica , Periostio , Posmenopausia/metabolismo , Teriparatido/administración & dosificación , Anciano , Densidad Ósea/efectos de los fármacos , Hueso Esponjoso/metabolismo , Hueso Esponjoso/patología , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Osteogénesis/efectos de los fármacos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/patología , Periostio/metabolismo , Periostio/patología , Factores de Tiempo , Ácido Zoledrónico
20.
Curr Med Res Opin ; 31(9): 1665-75, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26121328

RESUMEN

OBJECTIVE: To compare fractures and fracture-related resource utilization (RU) among patients with a recent fracture and treated with teriparatide (TPTD) to a matched cohort of patients not treated with TPTD (non-TPTD). RESEARCH DESIGN AND METHODS: Women aged 50 years or older initiating TPTD (N = 5314; index date between 1 January 2007 and 31 December 2012) were identified in an insurance claims database. Patients with fragility fracture (hip, pelvis, clavicle, humerus, wrist, leg or spine) during the 12 months prior to the index date (N = 1164) were selected to control for unmeasured confounding due to absence of bone mineral density test levels. TPTD patients were matched to the non-TPTD cohort using propensity score and exact matching (N = 912). Relative risk (RR) of fracture and fracture-related RU were estimated by Cox proportional hazard modeling, adjusted for potential fracture risk factors. RESULTS: Fractures were observed in 4.6%, 8.6%, 10.3%, and 11.3% of TPTD patients and in 9.2%, 15.2%, 19.2% and 21.7% of non-TPTD patients over 6, 12, 18, and 24 months, respectively. The adjusted RR reduction in TPTD was 36% (RR = 0.64, 95% CI: 0.44-0.94) during 6 months, 27% (RR = 0.73, 95% CI: 0.54-0.97) during 12 months, 28% (RR = 0.72, 95% CI: 0.55-0.93) during 18 months, and 28% (RR = 0.72, 95% CI: 0.56-0.92) during 24 months versus matched non-TPTD patients. Fracture-related RU followed a similar trend to that observed for fracture risk. CONCLUSIONS: This real-world study found TPTD to be more effective in reducing risk of fragility fractures as early as 6 months with continuous treatment benefit up to 24 months compared to a matched non-TPTD cohort. TPTD patients experienced lower rates of fracture-related RU than non-TPTD patients. Key study limitations include the inability to confirm reported diagnostic and procedural codes and the absence of uninsured and individually insured patients in the claims database.


Asunto(s)
Osteoporosis Posmenopáusica , Fracturas Osteoporóticas , Teriparatido/uso terapéutico , Anciano , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Recursos en Salud/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Humanos , Persona de Mediana Edad , Evaluación de Necesidades , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/diagnóstico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/epidemiología , Fracturas Osteoporóticas/clasificación , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/terapia , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...