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1.
J Immunother Cancer ; 11(3)2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36948505

RESUMEN

BACKGROUND: This phase 1 study evaluated PF-06753512, a vaccine-based immunotherapy regimen (PrCa VBIR), in two clinical states of prostate cancer (PC), metastatic castration-resistant PC (mCRPC) and biochemical recurrence (BCR). METHODS: For dose escalation, patients with mCRPC received intramuscular PrCa VBIR (adenovirus vector and plasmid DNA expressing prostate-specific membrane antigen (PSMA), prostate-specific antigen (PSA), and prostate stem cell antigen (PSCA)) with or without immune checkpoint inhibitors (ICIs, tremelimumab 40 or 80 mg with or without sasanlimab 130 or 300 mg, both subcutaneous). For dose expansion, patients with mCRPC received recommended phase 2 dose (RP2D) of PrCa VBIR plus tremelimumab 80 mg and sasanlimab 300 mg; patients with BCR received PrCa VBIR plus tremelimumab 80 mg (Cohort 1B-BCR) or tremelimumab 80 mg plus sasanlimab 130 mg (Cohort 5B-BCR) without androgen deprivation therapy (ADT). The primary endpoint was safety. RESULTS: Ninety-one patients were treated in dose escalation (mCRPC=38) and expansion (BCR=35, mCRPC=18). Overall, treatment-related and immune-related adverse events occurred in 64 (70.3%) and 39 (42.9%) patients, with fatigue (40.7%), influenza-like illness (30.8%), diarrhea (23.1%), and immune-related thyroid dysfunction (19.8%) and rash (15.4%), as the most common. In patients with mCRPC, the objective response rate (ORR, 95% CI) was 5.6% (1.2% to 15.4%) and the median radiographic progression-free survival (rPFS) was 5.6 (3.5 to not estimable) months for all; the ORR was 16.7% (3.6% to 41.4%) and 6-month rPFS rate was 45.5% (24.9% to 64.1%) for those who received RP2D with measurable disease (n=18). 7.4% of patients with mCRPC achieved a ≥50% decline in baseline PSA (PSA-50), with a median duration of 4.6 (1.2-45.2) months. In patients with BCR, 9 (25.7%) achieved PSA-50; the median duration of PSA response was 3.9 (1.9-4.2) and 10.1 (6.9-28.8) months for Cohorts 5B-BCR and 1B-BCR. Overall, antigen specific T-cell response was 88.0% to PSMA, 84.0% to PSA, and 80.0% to PSCA. CONCLUSIONS: PrCa VBIR overall demonstrated safety signals similar to other ICI combination trials; significant side effects were seen in some patients with BCR. It stimulated antigen-specific immunity across all cohorts and resulted in modest antitumor activity in patients with BCR without using ADT. TRIAL REGISTRATION NUMBER: NCT02616185.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Vacunas , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Docetaxel/uso terapéutico , Antígeno Prostático Específico , Antagonistas de Andrógenos/uso terapéutico , Inmunoterapia , Hormonas/uso terapéutico
2.
Cancer Immunol Immunother ; 72(2): 287-300, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35829790

RESUMEN

The development of therapeutic cancer vaccines remains an active area, although previous approaches have yielded disappointing results. We have built on lessons from previous cancer vaccine approaches and immune checkpoint inhibitor research to develop VBIR, a vaccine-based immunotherapy regimen. Assessment of various technologies led to selection of a heterologous vaccine using chimpanzee adenovirus (AdC68) for priming followed by boosts with electroporation of DNA plasmid to deliver T cell antigens to the immune system. We found that priming with AdC68 rapidly activates and expands antigen-specific T cells and does not encounter pre-existing immunity as occurs with the use of a human adenovirus vaccine. The AdC68 vector does, however, induce new anti-virus immune responses, limiting its use for boosting. To circumvent this, boosting with DNA encoding the same antigens can be done repetitively to augment and maintain vaccine responses. Using mouse and monkey models, we found that the activation of both CD4 and CD8 T cells was amplified by combination with anti-CTLA-4 and anti-PD-1 antibodies. These antibodies were administered subcutaneously to target their distribution to vaccination sites and to reduce systemic exposure which may improve their safety. VBIR can break tolerance and activate T cells recognizing tumor-associated self-antigens. This activation lasts more than a year after completing treatment in monkeys, and inhibits tumor growth to a greater degree than is observed using the individual components in mouse cancer models. These results have encouraged the testing of this combination regimen in cancer patients with the aim of increasing responses beyond current therapies.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Vacunas de ADN , Humanos , Animales , Ratones , Linfocitos T CD8-positivos , Antígenos de Neoplasias , Vacunación/métodos , Modelos Animales de Enfermedad , Autoantígenos
3.
Nature ; 585(7823): 63-67, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32879503

RESUMEN

Rechargeable lithium-ion batteries with high energy density that can be safely charged and discharged at high rates are desirable for electrified transportation and other applications1-3. However, the sub-optimal intercalation potentials of current anodes result in a trade-off between energy density, power and safety. Here we report that disordered rock salt4,5 Li3+xV2O5 can be used as a fast-charging anode that can reversibly cycle two lithium ions at an average voltage of about 0.6 volts versus a Li/Li+ reference electrode. The increased potential compared to graphite6,7 reduces the likelihood of lithium metal plating if proper charging controls are used, alleviating a major safety concern (short-circuiting related to Li dendrite growth). In addition, a lithium-ion battery with a disordered rock salt Li3V2O5 anode yields a cell voltage much higher than does a battery using a commercial fast-charging lithium titanate anode or other intercalation anode candidates (Li3VO4 and LiV0.5Ti0.5S2)8,9. Further, disordered rock salt Li3V2O5 can perform over 1,000 charge-discharge cycles with negligible capacity decay and exhibits exceptional rate capability, delivering over 40 per cent of its capacity in 20 seconds. We attribute the low voltage and high rate capability of disordered rock salt Li3V2O5 to a redistributive lithium intercalation mechanism with low energy barriers revealed via ab initio calculations. This low-potential, high-rate intercalation reaction can be used to identify other metal oxide anodes for fast-charging, long-life lithium-ion batteries.

4.
Cancer Treat Rev ; 76: 1-9, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30913454

RESUMEN

Although recent advances in the treatment of castration-resistant prostate cancer (CRPC) have significantly improved patient outcomes, advanced prostate cancer is still associated with substantial morbidity and mortality, particularly in patients who develop resistance after multiple lines of therapy. Various cell signaling, DNA repair, and epigenetic enzymatic pathways are being targeted with small-molecule inhibitors in order to identify treatment strategies for patients with CRPC. In this review, we discuss novel targets and agents, studied preclinically and now being validated in clinical trials, including poly ADP-ribose polymerase (PARP), enhancer of zeste homologue 2 (EZH2), hedgehog pathway, MDM2/p53, and tyrosine kinase inhibitors. Further, we outline current approaches for novel prostate cancer vaccines such as DCVAC/PCa, PROSTVAC-V/F, MVI-816, CV9104, and PF-06753512. This wide spectrum of potential treatment strategies holds promise for additional improvements in the treatment of patients with CRPC, as these novel agents are aimed at targets known to be associated with growth and malignant progression of prostate cancer. If primary study endpoints are met, findings from ongoing phase III trials of well-tolerated and active combinations may provide new effective treatment options for advanced prostate cancer and thereby contribute to enhanced disease control in CRPC patients.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración/terapia , Animales , Vacunas contra el Cáncer/administración & dosificación , Humanos , Masculino , Terapia Molecular Dirigida/métodos , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/inmunología , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
Clin Exp Optom ; 101(6): 793-798, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30021246

RESUMEN

BACKGROUND: The number of Australians living with vision impairment or blindness is expected to increase substantially due to the ageing population and prevalence of age-related eye disease. In response, the Australian College of Optometry (ACO) commenced a low vision clinic in 2013. The ACO is a not-for-profit organisation providing eye-care services to more than 60,000 Victorians per year experiencing economic or social disadvantage. Consultation fees are bulk-billed to the Australian national health care scheme - Medicare - while spectacles and visual aids are subsidised through the state government-funded Victorian Eyecare Service. The aim of this study was to determine the profile and prescribing patterns of the new optometry-led low vision clinic, and report the findings of a short-term loan magnifier pilot study. METHODS: A retrospective audit of 270 patient records was conducted. Additionally, a short-term loan magnifier program was pilot tested to ascertain the demand for, and benefits of, such a program among this cohort. RESULTS: The median age was 77 years (interquartile range 64 to 85 years), with 52 per cent being female. The main cause of vision impairment was age-related macular degeneration (40 per cent). At least one-third primarily spoke a language other than English. The majority (75 per cent) were referred by the optometrist to the onsite consultant occupational therapist for immediate assistance with activities of daily living and onward referral for additional comprehensive services, as required. Of the 49 participants who completed the loan magnifier study, only nine exchanged the magnifier/s initially prescribed. CONCLUSIONS: The ACO has established a low vision service within a large optometry clinic for people experiencing social and economic disadvantage. Where a program of subsidised low-cost magnifiers is available, there is little benefit to short-term loans of magnifiers. Providing basic affordable low vision aids and rehabilitation within a large primary care optometry setting can facilitate acceptability and uptake of low vision services that increase quality of life.


Asunto(s)
Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Optometría/organización & administración , Universidades/organización & administración , Baja Visión/rehabilitación , Personas con Daño Visual/rehabilitación , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Auditoría Médica , Persona de Mediana Edad , Proyectos Piloto , Calidad de Vida , Estudios Retrospectivos , Auxiliares Sensoriales , Victoria , Visión Binocular/fisiología , Baja Visión/diagnóstico , Agudeza Visual/fisiología
6.
J Natl Black Nurses Assoc ; 27(2): 26-31, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29932593

RESUMEN

Biomedical literature often cites that populations of African ancestry experience lower incidence and prevalence of osteoporosis compared to White populations. Diverse skeletal tissue physiology and sociocultural factors may exist in sub-Saharan African populations and the diaspora, which confer advantages against age-associated bone loss and osteoporosis through differing mechanisms. Nevertheless, the fallacious and erroneous understandings of race that are frequently applied to explain this reference should be critically re-evaluated, warranting a new framework for rethinking the epidemiology of osteoporosis. Future research of population differences in skeletal physiology should be multidisciplinary, and the interpretations should encompass evolutionary, politico-ecological, and biocultural perspectives to avoid the common misconceptions regarding human biological variations.


Asunto(s)
Población Negra/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , Osteoporosis/epidemiología , Población Blanca/estadística & datos numéricos , Humanos , Incidencia , Prevalencia
7.
J Anthropol Sci ; 89: 109-25, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21368344

RESUMEN

An Imperial Roman sample from the Isola Sacra necropolis (100-300 A.D.) offered an opportunity to histologically examine bone loss and intraskeletal variability in an urban archaeological population. Rib and femur samples were analyzed for static indices of bone remodeling and measures of bone mass. The Imperial Romans experienced normal age-associated bone loss via increased intracortical porosity and endosteal expansion, with females exhibiting greater bone loss and bone turnover rates than in males. Life events such as menopause and lactation coupled with cultural attitudes and practices regarding gender and food may have led to increased bone loss in females. Remodeling dynamics differ between the rib and femur and the higher remodeling rates in the rib may be attributed to different effective age of the adult compacta or loading environment. This study demonstrates that combining multiple methodologies to examine bone loss is necessary to shed light on the biocultural factors that influence bone mass and bone loss.


Asunto(s)
Osteoporosis/patología , Mundo Romano/historia , Adulto , Factores de Edad , Análisis de Varianza , Arqueología , Remodelación Ósea , Femenino , Fémur/anatomía & histología , Fémur/patología , Historia Antigua , Humanos , Masculino , Persona de Mediana Edad , Costillas/anatomía & histología , Costillas/patología
8.
Am J Physiol Endocrinol Metab ; 295(5): E1142-51, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18728225

RESUMEN

c-Jun NH(2)-terminal kinase (JNK) plays an important role in insulin resistance; however, identification of pharmacologically potent and selective small molecule JNK inhibitors has been limited. Compound A has a cell IC(50) of 102 nM and is at least 100-fold selective against related kinases and 27-fold selective against glycogen synthase kinase-3beta and cyclin-dependent kinase-2. In C57BL/6 mice, compound A reduced LPS-mediated increases in both plasma cytokine levels and phosphorylated c-Jun in adipose tissue. Treatment of mice fed a high-fat diet with compound A for 3 wk resulted in a 13.1 +/- 1% decrease in body weight and a 9.3 +/- 1.5% decrease in body fat, compared with a 6.6 +/- 2.1% increase in body weight and a 6.7 +/- 2.1% increase in body fat in vehicle-treated mice. Mice pair fed to those that received compound A exhibited a body weight decrease of 7 +/- 1% and a decrease in body fat of 1.6 +/- 1.3%, suggesting that reductions in food intake could not account solely for the reductions in adiposity observed. Compound A dosed at 30 mg/kg for 13 days in high-fat fed mice resulted in a significant decrease in phosphorylated c-Jun in adipose tissue accompanied by a decrease in weight and reductions in glucose and triglycerides and increases in insulin sensitivity to levels comparable with those in lean control mice. The ability of compound A to reduce the insulin-stimulated phosphorylation of insulin receptor substrate-1 (IRS-1) von Ser307 and partially reverse the free fatty acid inhibition of glucose uptake in 3T3L1 adipocytes, suggests that enhancement of insulin signaling in addition to weight loss may contribute to the effects of compound A on insulin sensitization in vivo. Pharmacological inhibition of JNK using compound A may therefore offer an effective therapy for type 2 diabetes mediated at least in part via weight reduction.


Asunto(s)
Aminopiridinas/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Células 3T3-L1 , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Aminopiridinas/farmacocinética , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Citocinas/sangre , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/farmacología , Ingestión de Alimentos/efectos de los fármacos , Humanos , Insulina/sangre , Insulina/farmacología , Proteínas Sustrato del Receptor de Insulina/metabolismo , Resistencia a la Insulina , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Lipopolisacáridos/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteína Quinasa 8 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/etiología , Obesidad/patología , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas c-jun/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Células U937
9.
Genes Dev ; 21(2): 160-74, 2007 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-17234882

RESUMEN

Spt6 promotes transcription elongation at many genes and functions as a histone H3 chaperone to alter chromatin structure during transcription. We show here that mammalian Spt6 binds Ser2-phosphorylated (Ser2P) RNA polymerase II (RNAPII) through a primitive SH2 domain, which recognizes phosphoserine rather than phosphotyrosine residues. Surprisingly, a point mutation in the Spt6 SH2 domain (R1358K) blocked binding to RNAPIIo without affecting transcription elongation rates in vitro. However, HIV-1 and c-myc RNAs formed in cells expressing the mutant Spt6 protein were longer than normal and contained splicing defects. Ectopic expression of the wild-type, but not mutant, Spt6 SH2 domain, caused bulk poly(A)+ RNAs to be retained in the nucleus, further suggesting a widespread role for Spt6 in mRNA processing or assembly of export-competent mRNP particles. We cloned the human Spt6-interacting protein, hIws1 (interacts with Spt6), and found that it associates with the nuclear RNA export factor, REF1/Aly. Depletion of endogenous hIws1 resulted in mRNA processing defects, lower levels of REF1/Aly at the c-myc gene, and nuclear retention of bulk HeLa poly(A)+ RNAs in vivo. Thus binding of Spt6 to Ser2-P RNAPII provides a cotranscriptional mechanism to recruit Iws1, REF1/Aly, and associated mRNA processing, surveillance, and export factors to responsive genes.


Asunto(s)
Proteínas/metabolismo , ARN Polimerasa II/metabolismo , Empalme del ARN , ARN Mensajero/metabolismo , Dominios Homologos src , Sustitución de Aminoácidos , Animales , Far-Western Blotting , Núcleo Celular/metabolismo , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Exorribonucleasas/metabolismo , Complejo Multienzimático de Ribonucleasas del Exosoma , VIH-1/genética , Células HeLa , Humanos , Ratones , Proteínas Nucleares/metabolismo , Fosfoserina , Mutación Puntual , Regiones Promotoras Genéticas , Proteínas de Unión al ARN , Proteínas Recombinantes/metabolismo , Factores de Transcripción , Activación Transcripcional
10.
Am J Phys Anthropol ; 130(2): 214-26, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16365857

RESUMEN

This study employs regression analysis to explore population and sex differences in the pattern of age-associated bone loss, as reflected by histomorphometric variables that are measures of intracortical and endocortical bone remodeling. A comparison of an African American sample from the Washington Park Cemetery in St. Louis, Missouri, and a European American rib sample composed of cadavers, autopsies, and forensic cases from Missouri reveals the existence of complex age-associated patterns for differences in measures of intracortical remodeling and cortical area. Females from the two samples express similar bone dimensions and dynamics. The African American females appear to lose more bone than their male counterparts, but this difference is absent in the European American sample. When age-associated patterns are considered, it is in the younger cohorts that African Americans exhibit greater relative cortical area than European Americans, but this is reversed in the older ages, when the latter group manifests greater bone mass. The European American males consistently differ in the slopes and intercepts for the variables compared to the other groups, and differences are highly significant with African American females, with the former group maintaining bone mass while the latter exhibit a more rapid bone loss. Achieving larger relative cortical area due to smaller endosteal area, coupled with better bone quality due to lower intracortical porosity early in life, may be a mechanism by which African Americans, especially females, maintain adequate bone mass in older ages, which buffers them from bone loss and related fragility fractures despite higher rates of intracortical remodeling and endosteal expansion later in life. These results suggest that both genetic and environmental factors are responsible for the differences in bone remodeling and bone mass observed between these samples.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Remodelación Ósea/fisiología , Costillas/fisiología , Población Blanca/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Enfermedades Óseas Metabólicas/etnología , Enfermedades Óseas Metabólicas/patología , Femenino , Fracturas Espontáneas/etnología , Fracturas Espontáneas/patología , Humanos , Masculino , Persona de Mediana Edad , Medio Oeste de Estados Unidos , Modelos Estadísticos , Análisis de Regresión , Factores de Riesgo , Caracteres Sexuales
11.
J Neurochem ; 95(1): 200-9, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16181424

RESUMEN

Cyclic AMP is the primary second messenger mediating odorant signal transduction in mammals. A number of studies indicate that cyclic GMP is also involved in a variety of other olfactory signal transduction processes, including adaptation, neuronal development, and long-term cellular responses in the setting of odorant stimulation. However, the mechanisms that control the production and degradation of cGMP in olfactory sensory neurons (OSNs) remain unclear. Here, we investigate these mechanisms using primary cultures of OSNs. We demonstrate that odorants increase cGMP levels in intact OSNs in vitro. Different from the rapid and transient cAMP responses to odorants, the cGMP elevation is both delayed and sustained. Inhibition of soluble guanylyl cyclase and heme oxygenase blocks these odorant-induced cGMP increases, whereas inhibition of cGMP PDEs (phosphodiesterases) increases this response. cGMP PDE activity is increased by odorant stimulation, and is sensitive to both ambient calcium and cAMP concentrations. Calcium stimulates cGMP PDE activity, whereas cAMP and protein kinase A appears to inhibit it. These data demonstrate a mechanism by which odorant stimulation may regulate cGMP levels through the modulation of cAMP and calcium level in OSNs. Such interactions between odorants and second messenger systems may be important to the integration of immediate and long-term responses in the setting odorant stimulation.


Asunto(s)
GMP Cíclico/metabolismo , Membranas Intracelulares/metabolismo , Neuronas Receptoras Olfatorias/metabolismo , 3',5'-GMP Cíclico Fosfodiesterasas/metabolismo , Adenilil Ciclasas/metabolismo , Animales , Calcio/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , GMP Cíclico/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Guanilato Ciclasa/antagonistas & inhibidores , Guanilato Ciclasa/química , Guanilato Ciclasa/metabolismo , Hemo Oxigenasa (Desciclizante)/antagonistas & inhibidores , Odorantes , Hidrolasas Diéster Fosfóricas/metabolismo , Solubilidad , Factores de Tiempo
12.
PLoS Biol ; 2(10): e294, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15328533

RESUMEN

Endurance exercise training can promote an adaptive muscle fiber transformation and an increase of mitochondrial biogenesis by triggering scripted changes in gene expression. However, no transcription factor has yet been identified that can direct this process. We describe the engineering of a mouse capable of continuous running of up to twice the distance of a wild-type littermate. This was achieved by targeted expression of an activated form of peroxisome proliferator-activated receptor delta (PPARdelta) in skeletal muscle, which induces a switch to form increased numbers of type I muscle fibers. Treatment of wild-type mice with PPARdelta agonist elicits a similar type I fiber gene expression profile in muscle. Moreover, these genetically generated fibers confer resistance to obesity with improved metabolic profiles, even in the absence of exercise. These results demonstrate that complex physiologic properties such as fatigue, endurance, and running capacity can be molecularly analyzed and manipulated.


Asunto(s)
Fibras Musculares Esqueléticas/metabolismo , PPAR delta/fisiología , Condicionamiento Físico Animal , Animales , ADN Mitocondrial/metabolismo , Etiquetas de Secuencia Expresada , Regulación de la Expresión Génica , Ligandos , Metabolismo de los Lípidos , Ratones , Ratones Transgénicos , Mitocondrias/metabolismo , Modelos Estadísticos , Obesidad/metabolismo , Oxígeno/metabolismo , Esfuerzo Físico , Estructura Terciaria de Proteína , Carrera , Transducción de Señal , Factores de Tiempo
13.
Genes Dev ; 18(2): 144-56, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14729568

RESUMEN

The recruitment of coactivators by nuclear hormone receptors (NRs) promotes transcription by subverting chromatin-mediated repression. Although the histone methylation enzyme CARM1 and an ATP-remodeling complex have been individually implicated in nuclear receptor-dependent transcription, neither a functional nor mechanistic linkage between these systems has been identified. In the process of purifying endogenous CARM1-interacting proteins, we identified an associated complex, nucleosomal methylation activator complex (NUMAC), which includes at least eight components of SWI/SNF, including the ATPase BRG1. In the NUMAC complex, the methylase, CARM1, acquires the ability to covalently modify nucleosomal histones, and the directed nucleosome versus free core histone methylation-specificity change is increased dramatically. Reciprocally, CARM1 stimulates the ATPase activity of BRG1, a key component in nucleosome remodeling. In vivo, CARM1 and BRG1 coassemble on an estrogen receptor (ER)-target gene to cooperatively activate ER-dependent transcription. This association of ATP-remodeling factors with HMT CARM1 defines a new component of regulation in the nuclear hormone-signaling pathway.


Asunto(s)
Proteínas Cromosómicas no Histona/metabolismo , Proteína-Arginina N-Metiltransferasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transducción de Señal/fisiología , Factores de Transcripción/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Humanos , Sustancias Macromoleculares , Metilación , Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/aislamiento & purificación , Especificidad por Sustrato
14.
Methods Enzymol ; 364: 205-23, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14631847

RESUMEN

Activation of hormone target genes requires chromatin remodeling and histone modifications. The properties of the two PRMT coactivators. PRMT1 and CARM1, are compared in Table I. One can envision many scenarios in which histone arginine methylation contributes to transcriptional regulation. For example, it could be analogous to histone H3 K4 methylation by Set9, which blocks the HDAC NuRD complex from association and simultaneously impairs Suv39 h 1-mediated methylation at K9 of H3 (H3-K9). As a result, H3 K4 methylation by Set9 potentiates transcriptional activation. Histone arginine methylation might also promote or antagonize other histone-modifying enzymes. It has been shown that PRMT1-methylated histone H4 becomes a better substrate for p300 and, conversely, the acetylated histones are poor substrates for methylation by PRMT1. As for CARM1, acetylation of multiple lysines within histone H3 facilitates arginine methylation of by CARM1. Since PRMT1 and CARM1 methylate H4 and H3 tails, respectively, and each contributes to activation of the nuclear receptor response, it implicates the "histone code" as the physical template of hormone signaling. However, it remains to be resolved whether p160 family coactivators simultaneously recruit CARM1 and PRMT1 to specific target genes, and the order of the series of modifications on individual histone tails in vivo. Time-course studies of [table: see text] cofactor recruitment by ChIPs will be necessary to decipher the modification patterns. Another useful approach to analyze the function of NR cofactors on target gene transcription is the chromatin-dependent in vitro transcription system. As increasing amounts of evidence indicate that one HAT can be acetylated by another HAT, or methylated by HMT, it would not be surprising that transcription factors and their coactivators are bona fide substrates for protein modification.


Asunto(s)
Acetilación , Bioquímica/métodos , Metilación , Receptores Citoplasmáticos y Nucleares/química , ADP-Ribosil Ciclasa/biosíntesis , ADP-Ribosil Ciclasa 1 , Antígenos CD/biosíntesis , Núcleo Celular/metabolismo , Cromatina/química , Cromatina/metabolismo , Cromatografía en Gel , Reactivos de Enlaces Cruzados/farmacología , Detergentes/farmacología , Electroforesis , Regulación de la Expresión Génica , Células HL-60 , Histonas , Humanos , Ligandos , Glicoproteínas de Membrana , Modelos Químicos , Modelos Moleculares , Octoxinol/farmacología , Estructura Terciaria de Proteína , Proteína-Arginina N-Metiltransferasas/química , Especificidad por Sustrato , Transcripción Genética , Activación Transcripcional , Urea/farmacología
15.
Mol Cell Biol ; 22(21): 7543-52, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12370301

RESUMEN

FCP1, a phosphatase specific for the carboxy-terminal domain of RNA polymerase II (RNAP II), was found to stimulate transcript elongation by RNAP II in vitro and in vivo. This activity is independent of and distinct from the elongation-stimulatory activity associated with transcription factor IIF (TFIIF), and the elongation effects of TFIIF and FCP1 were found to be additive. Genetic experiments resulted in the isolation of several distinct fcp1 alleles. One of these alleles was found to suppress the slow-growth phenotype associated with either the reduction of intracellular nucleotide concentrations or the inhibition of other transcription elongation factors. Importantly, this allele of fcp1 was found to be lethal when combined individually with two mutations in the second-largest subunit of RNAP II, which had been shown previously to affect transcription elongation.


Asunto(s)
Proteínas Nucleares , Fosfoproteínas Fosfatasas/metabolismo , Fosfoproteínas Fosfatasas/fisiología , Transcripción Genética , Factores de Elongación Transcripcional , Alelos , Animales , Aprotinina , Secuencia de Bases , División Celular , Línea Celular , Proteínas Fúngicas/metabolismo , Genotipo , Células HeLa , Humanos , Insectos , Cinética , Ratones , Ratones Noqueados , Modelos Genéticos , Datos de Secuencia Molecular , Mutación , Fenotipo , Unión Proteica , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Temperatura , Factores de Transcripción/genética , Factores de Transcripción TFII/metabolismo
16.
J Forensic Sci ; 47(1): 12-8, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12064637

RESUMEN

Previously developed histological age-estimating methods have been based on samples lacking interpopulation variability. A comparison of age-associated rib histomorphometrics between an European-American sample and an African-American sample indicates that ethnicity can have a significant effect on osteon population density (OPD), osteon cross-sectional area (On.Ar), and relative cortical area (Ct.Ar/Tt.Ar). Based upon these findings, new histological age-predicting formulae are presented that are recommended when estimating age for African-American or European-American skeletal remains. A general formula that is applicable to remains of unknown ethnicity is also provided.


Asunto(s)
Determinación de la Edad por el Esqueleto/métodos , Población Negra , Remodelación Ósea , Huesos/citología , Modelos Teóricos , Población Blanca , Adolescente , Adulto , África/etnología , Anciano , Anciano de 80 o más Años , Etnicidad , Europa (Continente)/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estados Unidos/etnología
17.
J Am Podiatr Med Assoc ; 92(2): 82-9, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11847259

RESUMEN

In the offset V-bunionectomy used for hallux valgus repair, both the Kalish and the Vogler variations have a long dorsal arm, but the apex is more distal in the Kalish procedure. This study investigated the effect that pin orientation and location of the osteotomy apex have on weightbearing stability. The authors studied saw bone models that were loaded to failure in an Instron 4201 materials testing machine and, in addition, designed, fabricated, and used a unique jig assembly to help minimize data variability. Statistically significant differences were found between the surgical techniques and pin orientations: the Kalish osteotomy was stronger than the Vogler procedure, and in both osteotomies, the plantarly directed Kirschner wire orientation was stronger than the dorsally directed orientation.


Asunto(s)
Hallux Valgus/cirugía , Osteotomía/instrumentación , Análisis de Varianza , Fenómenos Biomecánicos , Tornillos Óseos , Hilos Ortopédicos , Humanos , Modelos Anatómicos , Osteotomía/métodos , Sensibilidad y Especificidad , Estrés Mecánico , Soporte de Peso
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