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1.
Mol Biol Evol ; 38(12): 5735-5751, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34436590

RESUMEN

In most eukaryotes, transfer RNAs (tRNAs) are one of the very few classes of genes remaining in the mitochondrial genome, but some mitochondria have lost these vestiges of their prokaryotic ancestry. Sequencing of mitogenomes from the flowering plant genus Silene previously revealed a large range in tRNA gene content, suggesting rapid and ongoing gene loss/replacement. Here, we use this system to test longstanding hypotheses about how mitochondrial tRNA genes are replaced by importing nuclear-encoded tRNAs. We traced the evolutionary history of these gene loss events by sequencing mitochondrial genomes from key outgroups (Agrostemma githago and Silene [=Lychnis] chalcedonica). We then performed the first global sequencing of purified plant mitochondrial tRNA populations to characterize the expression of mitochondrial-encoded tRNAs and the identity of imported nuclear-encoded tRNAs. We also confirmed the utility of high-throughput sequencing methods for the detection of tRNA import by sequencing mitochondrial tRNA populations in a species (Solanum tuberosum) with known tRNA trafficking patterns. Mitochondrial tRNA sequencing in Silene revealed substantial shifts in the abundance of some nuclear-encoded tRNAs in conjunction with their recent history of mt-tRNA gene loss and surprising cases where tRNAs with anticodons still encoded in the mitochondrial genome also appeared to be imported. These data suggest that nuclear-encoded counterparts are likely replacing mitochondrial tRNAs even in systems with recent mitochondrial tRNA gene loss, and the redundant import of a nuclear-encoded tRNA may provide a mechanism for functional replacement between translation systems separated by billions of years of evolutionary divergence.


Asunto(s)
ARN de Transferencia , Solanum tuberosum , Genes Mitocondriales , Mitocondrias/genética , Mitocondrias/metabolismo , Plantas/genética , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Solanum tuberosum/genética , Solanum tuberosum/metabolismo
2.
J Am Psychiatr Nurses Assoc ; 26(2): 157-161, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30866709

RESUMEN

BACKGROUND: Persistent pain causes a significant decrease in quality of life and increases overall disability more than any other condition. Hypnotherapy is emerging as a treatment option for pain management; examination of this treatment modality and its effectiveness is needed. AIM(S): To examine evidence for effectiveness of hypnotherapy to treat persistent pain in adults. METHOD: A consolidated review was completed through searching biomedical and life sciences literature databases. RESULTS: Results were obtained through appraisal of six identified studies meeting inclusion criteria. Hypnotherapy decreases pain and improves pain-related function and quality of life outcomes to a greater extent than other psychological interventions or usual treatments. Furthermore, it has been shown to be effective in a variety of chronic pain conditions. CONCLUSIONS: Current treatment practices fail to alleviate pain adequately; there is sufficient evidence to suggest hypnotherapy as a viable treatment modality for persistent pain. However, more definitive studies are needed for it to be a first-line intervention.


Asunto(s)
Dolor Crónico/terapia , Hipnosis , Manejo del Dolor , Humanos , Calidad de Vida/psicología
3.
BMC Pharmacol Toxicol ; 15: 77, 2014 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-25539648

RESUMEN

BACKGROUND: Safety of tenofovir disoproxil fumarate/emtricitabine (TDF-FTC) has been studied more extensively among HIV-infected patients than among HIV-uninfected people. Using data from a pre-exposure trial - FEM-PrEP -, we determined the cumulative probabilities of grade 1+ ALT, AST and creatinine and grade 2+ phosphorus toxicities; ALT/AST toxicities by baseline hepatitis B status; and change in mean creatinine, phosphorus, ALT and AST levels controlling for TDF-FTC adherence. METHODS AND FINDINGS: FEM-PrEP was a randomized, blinded, placebo-controlled trial of daily TDF-FTC among women in Africa. Enrolled women were in general good health, HIV antibody negative, 18 to 35 years old, hepatitis B surface antigen negative, and had normal hepatic and renal function at baseline. AST, ALT, phosphorus and serum creatinine were measured regularly throughout the trial. TDF-FTC concentrations were measured to assess adherence to TDF-FTC. The cumulative probabilities of grade 1+ creatininemia and grade 2+ phosphatemia toxicities were not statistically different between TDF-FTC and placebo arms. The cumulative probabilities of grade 1+ ALT and AST toxicities were higher among participants in the TDF-FTC arm than in the placebo arm (p = 0.03 for both). The proportions of grade 1+ and grade 2+ ALT or AST toxicities were significantly higher in participants who were hepatitis B virus surface antibody (HBsAb) positive than in those who were HBsAb-negative. Women with good adherence had higher mean change from baseline to week 4 in their AST levels (2.90 (0.37, 5.42); p = 0.025) than women with less than good adherence. CONCLUSIONS: We did not observe a significant relationship between randomization to TDF-FTC and creatinine or phosphorus toxicities. Women randomized to TDF-FTC had higher rates of mild to moderate ALT/AST toxicities, especially women with prior hepatitis B virus exposure. We also observed a significant increase in AST from baseline to week 4 among women who had higher adherence to TDF-FTC during that interval. TRIAL REGISTER: #NCT00625404, February 19, 2008.


Asunto(s)
Adenina/análogos & derivados , Fármacos Anti-VIH/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Desoxicitidina/análogos & derivados , Enfermedades Renales/inducido químicamente , Organofosfonatos/efectos adversos , Inhibidores de la Transcriptasa Inversa/efectos adversos , Adenina/efectos adversos , Adolescente , Adulto , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Población Negra , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Creatinina/sangre , Desoxicitidina/efectos adversos , Método Doble Ciego , Quimioterapia Combinada , Emtricitabina , Femenino , Infecciones por VIH/prevención & control , Humanos , Enfermedades Renales/sangre , Fósforo/sangre , Profilaxis Pre-Exposición , Tenofovir , Adulto Joven
4.
Biochem Biophys Res Commun ; 454(1): 234-8, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25450386

RESUMEN

The melanocortin 3 receptor (MC3R) is involved in regulation of energy homeostasis. However, its transcript structure is not well understood. We therefore studied initiation and termination sites for hypothalamic murine Mc3r and human MC3R transcripts. Rapid Amplification of cDNA Ends (RACE) was performed for the 5' and 3' ends of murine and human hypothalamic RNA. 5' RACE experiments using hypothalamic murine RNA indicated mouse hypothalamus expresses two major Mc3r transcription start sites: one with a 5' UTR approximately 368 bases in length and another previously unknown transcript with a 5' UTR approximately 440 bases in length. 5' RACE experiments using human hypothalamic RNA identified a 5' UTR beginning 533 bases upstream of the start codon with a 248 base splice. 3' RACE experiments using hypothalamic murine RNA indicated the 3' UTR terminates approximately 1286 bases after the translational stop codon, with a previously unknown 787 base splice between consensus splice donor and acceptor sites. 3' RACE experiments using human MC3R transcript indicated the 3' UTR terminates approximately 115-160 bases after the translational stop codon. These data provide insight into melanocortin 3 receptor transcript structure.


Asunto(s)
Hipotálamo/metabolismo , Receptor de Melanocortina Tipo 3/genética , Regiones no Traducidas 3' , Regiones no Traducidas 5' , Animales , Secuencia de Bases , Cartilla de ADN/genética , Humanos , Ratones , Técnicas de Amplificación de Ácido Nucleico , Reacción en Cadena de la Polimerasa , Sitio de Iniciación de la Transcripción
5.
Stud Fam Plann ; 42(4): 283-90, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22292247

RESUMEN

One strategy for meeting the contraceptive needs of HIV-positive women is to integrate family planning into HIV services. In 2008 in Cross River State, Nigeria,family planning was integrated into antiretroviral (ART) services in five local government areas. A basic family planning/HIV integration model was implemented in three of these areas, and an enhanced model in the other two. We conducted baseline interviews in 2008 and follow-up interviews 12-14 months later with 274 female ART clients aged 18-45 in 2009 across the five areas. Unmet need for contraception was high at baseline (28-35 percent). We found that modern contraceptive use rose in the enhanced and basic groups; most of the increase was in consistent condom use. Despite an increase in family planning counseling by ART providers, referrals to family planning services for noncondom methods were low. We conclude by presenting alternative strategies for family planning/HIV integration in settings where large families and low contraceptive use are normative.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Conducta Anticonceptiva/estadística & datos numéricos , Prestación Integrada de Atención de Salud , Servicios de Planificación Familiar/métodos , Infecciones por VIH , Seropositividad para VIH/epidemiología , Adulto , Anticoncepción , Anticonceptivos/uso terapéutico , Dispositivos Anticonceptivos/estadística & datos numéricos , Prestación Integrada de Atención de Salud/métodos , Prestación Integrada de Atención de Salud/organización & administración , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Humanos , Nigeria/epidemiología , Educación Sexual/métodos
6.
J Manag Care Pharm ; 16(7): 482-91, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20726677

RESUMEN

BACKGROUND: Imatinib mesylate, an orally administered kinase inhibitor that targets the Kit (CD117) protein, currently has 10 approved indications including treatment of chronic myelogenous leukemia and metastatic gastrointestinal stromal tumors (GIST). Treatment with adjuvant imatinib following surgical resection of localized Kit-positive GIST, the most recent FDA-approved indication (December 2008), has been shown to significantly improve recurrence-free survival (RFS) compared with surgical resection alone. Although adjuvant imatinib has proven effective in clinical trials, it is important to consider the economic impact to health plans of introducing imatinib in accordance with its new labeled indication. OBJECTIVE: To evaluate the budgetary impact over a 3-year time horizon of treating patients with localized Kit-positive GIST with 1 year of adjuvant imatinib following surgical resection. METHODS: A Markov model was developed to predict patients' transitions across health states defined by initial treatment (surgical resection followed by adjuvant imatinib 400 milligrams [mg] daily versus surgical resection alone), recurrence, and progression. Treatments for a first recurrence were (a) imatinib 400 mg daily for recurrences following resection only or after completion of 1 year of treatment with imatinib 400 mg daily and (b) imatinib 800 mg daily for recurrence during active treatment with imatinib 400 mg daily. Treatments for further progression were imatinib 800 mg daily, sunitinib, or best supportive care (BSC) following imatinib 400 mg per day, and sunitinib or BSC following imatinib 800 mg daily. Recurrence rates were derived from the American College of Surgeons Oncology Group (ACOSOG) Z9001 clinical trial, which compared 1 year of adjuvant imatinib following surgical resection with surgical resection only. The total number of patients with localized and surgically resected GIST (incidence rate of 0.36 per 100,000) was estimated from epidemiologic studies of GIST. Uptake of treatment with imatinib was estimated from unpublished data from qualitative market research funded by the study sponsor. The uptake rate assumptions reflected both (a) the percentage of patients with Kitpositive disease and (b) the percentage of clinically eligible patients who would use imatinib. Costs were estimated by combining unit costs from published sources with expected resource utilization based on the clinical trial publication and National Comprehensive Cancer Network guidelines on the treatment of patients with GIST. To obtain estimates of the budgetary impact, we compared estimated health care costs with versus without adjuvant imatinib, where health care costs with imatinib reflected the costs of treatment minus cost offsets associated with delayed or avoided recurrence or progression. All "with" scenarios assumed no additional uses other than surgically resected localized Kit-positive GIST (i.e., no change in off-label use of imatinib). The budgetary impact was estimated for the first 3 years after the introduction of adjuvant imatinib in accordance with its new labeled indication in a hypothetical plan population of 10 million persons. Results were calculated both as total budgetary impact and as per member per month (PMPM) cost in 2009 dollars. Sensitivity analyses were performed to test the robustness of model results to changes in parameter estimates. RESULTS: The model predicted 36 incident resected GIST cases per year in a health plan of 10 million members. The estimated counts of cases treated with adjuvant imatinib were 10.8, 16.2, and 21.6 in the first, second, and third years after introduction, respectively, with the annual increases attributable to changes in the proportion of patients with resected GIST assumed to use imatinib (30% in year 1, rising to 45% in year 2 and 60% in year 3). The model predicted that treatment of these cases with imatinib will increase pharmacy costs by an additional $505,144 in the first year, $757,717 in the second year, and $1,010,289 in the third year. Increased resource use associated with monitoring patients during and after treatment with adjuvant imatinib would cost an additional $21,564, $38,145, and $56,605 in the first, second, and third years, respectively. Recurrence would be avoided or delayed in 7 patients over the 3-year period. Avoided or delayed recurrences would result in cost offsets of $61,583 in the first year, $156,702 in the second year, and $233,849 in the third year. The net budgetary impact was estimated to be $465,126 in the first year (less than $0.01 PMPM), $639,159 in the second year ($0.01 PMPM), and $833,044 in the third year ($0.01 PMPM). Results of sensitivity analyses indicated that the budgetary impact in the third year is most sensitive to changes in the price of adjuvant imatinib and recurrence rates. CONCLUSIONS: The model predicted that the introduction of adjuvant imatinib for treatment of surgically resected, localized, Kit-positive GIST will lead to a net budgetary impact of $0.01 PMPM in the third year after introduction assuming change in use only in accordance with the new labeled indication. Approximately 11.7%-21.9% of the cost of adjuvant imatinib is offset by the reduction in costs associated with GIST recurrence.


Asunto(s)
Antineoplásicos/uso terapéutico , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Modelos Económicos , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Antineoplásicos/economía , Benzamidas , Quimioterapia Adyuvante/economía , Quimioterapia Adyuvante/métodos , Terapia Combinada , Tumores del Estroma Gastrointestinal/economía , Tumores del Estroma Gastrointestinal/cirugía , Costos de la Atención en Salud , Humanos , Mesilato de Imatinib , Cadenas de Markov , Recurrencia Local de Neoplasia/economía , Recurrencia Local de Neoplasia/prevención & control , Piperazinas/economía , Proteínas Proto-Oncogénicas c-kit/metabolismo , Pirimidinas/economía , Factores de Tiempo
7.
Cancer Genomics Proteomics ; 6(3): 189-94, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19487548

RESUMEN

BACKGROUND: Despite optimal primary treatment of ovarian cancer, overall prognosis is poor due to recurrences. While steroid hormone receptors are frequently expressed, the role of estrogen receptor (ER) in ovarian carcinogenesis, response to treatment or prognosis has not been established. We analyzed the gene-expression in response to estradiol (E2) and genistein (Gen) in ovarian cancer cells. MATERIALS AND METHODS: Cell lines (Br-1, UL-1; Oy-1), treated with E2 (10 nM) or Gen (5 microM), were used for gene expression profiling. RT-PCR and Western immunoblotting were used to further analyze gene expression data. RESULTS: Twenty-four genes were differentially regulated in ovarian cancer cell lines. C3, CLU, COL6A1, DLC1, NME1, NRIP1, PTEN, RAC2, S100A2 were down-regulated with E2 in Br-1 and UL-1 cells. MK167, SERPINB5, SLC7A5, CDK1NA, LCN2, PLAU, PHB2, CTSB, EGLN2, ERBB2, HMGB1, ID2, ITGB4, TOP2A were up-regulated in Oy-1 cells with E2 and/or genistein. ERBB2 and ID2 (E2 and Gen), LCN2, PHB2 and HMGB1 (Gen) were down-regulated in Br-1 cells. ERalpha and ERbeta were detected in all cell lines at different levels. CONCLUSION: Variable response of ovarian cancer cells to E2 and Gen was observed. Study of ERs including splice variants, co-regulatory molecules are necessary to understand the relevance of receptors.


Asunto(s)
Estradiol/farmacología , Expresión Génica/efectos de los fármacos , Genisteína/farmacología , Neoplasias Ováricas/genética , Fitoestrógenos/farmacología , Línea Celular Tumoral , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Ováricas/metabolismo , Prohibitinas , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
8.
Can J Clin Pharmacol ; 16(2): e331-45, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19531812

RESUMEN

BACKGROUND: The TNT study compared high dose atorvastatin (80 mg) versus moderate atorvastatin (10 mg) treatment in 10,001 patients with stable coronary heart disease (CHD), over 4.9 years. Intensive lipid-lowering with atorvastatin (80 mg) reduced major cardiovascular events by 22%. OBJECTIVES: To assess the cost-effectiveness of intensive lipid-lowering versus moderate lipid lowering treatment from the perspective of the Canadian Ministries of Health. METHODS: A lifetime Markov model was developed to predict cardiovascular (CV) events, costs, survival, and quality-adjusted life years (QALYs) for CHD patients receiving 80 mg versus 10 mg of atorvastatin. Predictions were also made for 10- and 5-year horizons. Treatment-specific event risks were used until five years. Beyond year five, equivalent CV risks were assumed for all patients. Medical-care costs and post-event survival were estimated using Canadian data. Health utility scores were obtained from published studies. Benefits and costs were discounted 5% annually. Probabilistic and deterministic sensitivity analyses were performed. RESULTS: Treatment with atorvastatin (80 mg) over a lifetime horizon resulted in increased costs (Can$16,542 vs. Can$15,365), survival (10.12 vs. 10.03 life years), and QALYs (7.71 vs. 7.61) per patient compared with atorvastatin (10 mg), yielding an incremental cost-effectiveness of Can$12,946 per life year gained and Can$11,969 per QALY. The incremental cost per QALY remained below Can$50,000 in 98.1% of 1000 simulations. Results were robust to variations in event hazard ratios, costs, health utility values, and discount rate. CONCLUSION: Intensive atorvastatin (80 mg) treatment is predicted to be cost-effective versus atorvastatin (10 mg) for CHD patients in Canada.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Ácidos Heptanoicos/economía , Inhibidores de Hidroximetilglutaril-CoA Reductasas/economía , Cadenas de Markov , Pirroles/economía , Anciano , Atorvastatina , Canadá , Enfermedades Cardiovasculares/economía , Análisis Costo-Beneficio , Relación Dosis-Respuesta a Droga , Femenino , Ácidos Heptanoicos/administración & dosificación , Ácidos Heptanoicos/uso terapéutico , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Masculino , Persona de Mediana Edad , Pirroles/administración & dosificación , Pirroles/uso terapéutico , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Análisis de Supervivencia
9.
Genetica ; 117(1): 27-35, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12656570

RESUMEN

Segregation distortion is increasingly recognized as a potentially powerful evolutionary force. This runs counter to the perception that non-Mendelian genes are rare genetic curiosities, a view that seems to be supported by the near ubiquity of the Mendelian system of inheritance. There are several reasons why segregation distortion may be more important than is evidenced by known empirical examples. One possibility is that the types of segregation distorters we have found are only a subset of a broader range of non-Mendelian systems, many of which go undetected. In this paper, we review what is known about the sex-linked meiotic drive system in the plant, Silene latifolia, and present some data on the mechanism of segregation distortion. We outline the general features that segregation distorters in plants and animals have in common. In some cases, such as the paucity of systems that directly alter meiotic segregation, there are likely to be inherent constraints on the range of systems that can possibly occur. Other generalities, however, support the notion that many forms of meiotic drive are possible, and that the known examples of segregation distortion are likely to be only subset of those that can possibly occur. Non-Mendelian genes may therefore have greater evolutionary importance than their current abundance in nature would suggest.


Asunto(s)
Segregación Cromosómica/genética , Drosophila/genética , Polen/genética , Silene/genética , Animales , Evolución Molecular , Gametogénesis , Meiosis , Polimorfismo Genético , Razón de Masculinidad , Cromosoma X
10.
Proc Natl Acad Sci U S A ; 99(17): 11265-9, 2002 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-12177435

RESUMEN

Some genetic elements spread infectiously in populations by increasing their rate of genetic transmission at the expense of other genes in the genome. These so-called selfish genetic elements comprise a substantial portion of eukaryotic genomes and have long been viewed as a potent evolutionary force. Despite this view, little is known about the evolutionary history of selfish genetic elements in natural populations, or their genetic effects on other portions of the genome. Here we use nuclear and chloroplast gene genealogies in two species of Silene to show the historical pattern of selection on a well known selfish genetic element, cytoplasmic male sterility. We provide evidence that evolution of cytoplasmic male sterility has been characterized by frequent turnovers of mutations in natural populations, thus supporting an epidemic model for the evolution of selfish genes, where new mutations repeatedly arise and rapidly sweep through populations.


Asunto(s)
ADN de Plantas/genética , Magnoliopsida/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Cloroplastos/genética , Europa (Continente) , Variación Genética , Impresión Genómica , Infertilidad/genética , Magnoliopsida/clasificación , Datos de Secuencia Molecular , Filogenia , Enfermedades de las Plantas/genética , Plantas Medicinales/clasificación , Plantas Medicinales/genética , Especificidad de la Especie
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