Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 594(7861): 100-105, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33981041

RESUMO

Ageing of the immune system, or immunosenescence, contributes to the morbidity and mortality of the elderly1,2. To define the contribution of immune system ageing to organism ageing, here we selectively deleted Ercc1, which encodes a crucial DNA repair protein3,4, in mouse haematopoietic cells to increase the burden of endogenous DNA damage and thereby senescence5-7 in the immune system only. We show that Vav-iCre+/-;Ercc1-/fl mice were healthy into adulthood, then displayed premature onset of immunosenescence characterized by attrition and senescence of specific immune cell populations and impaired immune function, similar to changes that occur during ageing in wild-type mice8-10. Notably, non-lymphoid organs also showed increased senescence and damage, which suggests that senescent, aged immune cells can promote systemic ageing. The transplantation of splenocytes from Vav-iCre+/-;Ercc1-/fl or aged wild-type mice into young mice induced senescence in trans, whereas the transplantation of young immune cells attenuated senescence. The treatment of Vav-iCre+/-;Ercc1-/fl mice with rapamycin reduced markers of senescence in immune cells and improved immune function11,12. These data demonstrate that an aged, senescent immune system has a causal role in driving systemic ageing and therefore represents a key therapeutic target to extend healthy ageing.


Assuntos
Envelhecimento/imunologia , Envelhecimento/fisiologia , Sistema Imunitário/imunologia , Sistema Imunitário/fisiologia , Imunossenescência/imunologia , Imunossenescência/fisiologia , Especificidade de Órgãos/imunologia , Especificidade de Órgãos/fisiologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Dano ao DNA/imunologia , Dano ao DNA/fisiologia , Reparo do DNA/imunologia , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Feminino , Envelhecimento Saudável/imunologia , Envelhecimento Saudável/fisiologia , Homeostase/imunologia , Homeostase/fisiologia , Sistema Imunitário/efeitos dos fármacos , Imunossenescência/efeitos dos fármacos , Masculino , Camundongos , Especificidade de Órgãos/efeitos dos fármacos , Rejuvenescimento , Sirolimo/farmacologia , Baço/citologia , Baço/transplante
2.
BMC Plant Biol ; 19(1): 405, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521126

RESUMO

BACKGROUND: Cotton is one of the most important commercial crops as the source of natural fiber, oil and fodder. To protect it from harmful pest populations number of newer transgenic lines have been developed. For quick expression checks in successful agriculture qPCR (quantitative polymerase chain reaction) have become extremely popular. The selection of appropriate reference genes plays a critical role in the outcome of such experiments as the method quantifies expression of the target gene in comparison with the reference. Traditionally most commonly used reference genes are the "house-keeping genes", involved in basic cellular processes. However, expression levels of such genes often vary in response to experimental conditions, forcing the researchers to validate the reference genes for every experimental platform. This study presents a data science driven unbiased genome-wide search for the selection of reference genes by assessing variation of > 50,000 genes in a publicly available RNA-seq dataset of cotton species Gossypium hirsutum. RESULT: Five genes (TMN5, TBL6, UTR5B, AT1g65240 and CYP76B6) identified by data-science driven analysis, along with two commonly used reference genes found in literature (PP2A1 and UBQ14) were taken through qPCR in a set of 33 experimental samples consisting of different tissues (leaves, square, stem and root), different stages of leaf (young and mature) and square development (small, medium and large) in both transgenic and non-transgenic plants. Expression stability of the genes was evaluated using four algorithms - geNorm, BestKeeper, NormFinder and RefFinder. CONCLUSION: Based on the results we recommend the usage of TMN5 and TBL6 as the optimal candidate reference genes in qPCR experiments with normal and transgenic cotton plant tissues. AT1g65240 and PP2A1 can also be used if expression study includes squares. This study, for the first time successfully displays a data science driven genome-wide search method followed by experimental validation as a method of choice for selection of stable reference genes over the selection based on function alone.


Assuntos
Genoma de Planta/genética , Gossypium/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Proteínas de Plantas/genética
3.
Biol Blood Marrow Transplant ; 24(1): 50-54, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28958896

RESUMO

In murine model systems inducible costimulator (ICOS) signaling has been implicated in the formation of chronic graft-versus-host disease (GVHD). Previously, we showed that chronic GVHD can be reproducibly produced in the dog hematopoietic cell transplantation (HCT) model and that ICOS expression is upregulated on T cells in dogs with chronic GVHD. The goal of the present study was to determine whether administration of a short course of anti-canine ICOS mAb could alter the rapid and progressive course of chronic GVHD. Five dogs underwent HCT from dog leukocyte antigen mismatched unrelated donors after total body irradiation. Postgrafting immunosuppression consisted of methotrexate (days 1, 3, 6, and 11) and cyclosporine (days -1 through 78). Anti-ICOS mAb (3 injections, 72 hours apart) was administered upon diagnosis of GVHD. One dog failed to respond to anti-ICOS mAb therapy and succumbed to chronic GVHD in a time course similar to control untreated dogs. Overall, anti-ICOS-treated dogs experienced a significant prolongation in survival from the time of diagnosis of chronic GVHD compared with control dogs. Within the limitations of the number of study dogs we suggest that a short course of anti-ICOS mAb may be useful in the treatment of chronic canine GVHD.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doença Enxerto-Hospedeiro/terapia , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Antígenos de Superfície , Modelos Animais de Doenças , Cães , Doença Enxerto-Hospedeiro/mortalidade , Transplante de Células-Tronco Hematopoéticas , Terapia de Imunossupressão/métodos , Taxa de Sobrevida , Resultado do Tratamento
4.
Curr Oncol Rep ; 17(12): 59, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26475774

RESUMO

The universal implementation of electronic health records has transformed the practice of medicine. However, there is a general perception that electronic health records impede effective communication with patients. Clinicians feel that they paradoxically spend more time doing nonclinical tasks like documentation and writing orders and less time interacting with their patients. This article evaluates the role of medical scribes in augmenting physician workflows and examines if employing a scribe can enhance physician-patient interactions.


Assuntos
Registros Eletrônicos de Saúde , Administradores de Registros Médicos , Papel do Médico , Relações Médico-Paciente , Humanos , Gerenciamento da Prática Profissional/organização & administração
5.
J Environ Biol ; 36(4): 883-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26364465

RESUMO

Agricultural soils of selected regions of Southwestern Karnataka, Peninsular India, were subjected to systematic mineralogical characterization along with the study of soil physical properties. Physical properties such as soil texture and micro porosity were studied using particle size analyses and positron annihilation lifetime analysis (PALS) technique, respectively. The latter was used to analyze micro porosity of agricultural soil. Both major and minor minerals were identified and confirmed by some analytical techniques like thin section study, powder X-ray diffraction, X-ray fluorescence spectroscopy and Fourier transform infrared spectroscopy.


Assuntos
Minerais/análise , Solo/química , Agricultura , Índia
6.
J Zoo Wildl Med ; 44(4): 1102-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24450079

RESUMO

An adult female, wild North American porcupine (Erethizon dorsatum) presented with bilateral cataracts and naso-ocular discharge. A pregnancy was identified by radiography with a near-full-term fetus, which was delivered stillborn 4 wk later with hard, developed quills. At that time, a repeated examination and further imaging, including computed tomography, demonstrated a uterine mass that was identified as a choriocarcinoma following ovariohysterectomy. Additionally, numerous exfoliated quills were discovered throughout the abdomen, most of which were removed during the surgical procedure. Ultimately, development of peritonitis despite medical care led to the porcupine's death. Necropsy confirmed a wide migration of the quills with extensive serosal adhesions and granulomas affecting liver, lungs, urinary bladder, kidneys, and gastrointestinal tract.


Assuntos
Morte Fetal/veterinária , Porcos-Espinhos , Complicações na Gravidez/veterinária , Animais , Coriocarcinoma/patologia , Coriocarcinoma/cirurgia , Coriocarcinoma/veterinária , Feminino , Gravidez , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia , Neoplasias Uterinas/veterinária
7.
Microsc Res Tech ; 86(6): 659-668, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37021725

RESUMO

Syzygium travancoricum Gamble popularly known as "Kulavettimaram" or "Kulirmaavu" is a least explored endemic endangered taxa of Southern Western Ghats, Kerala. The species is often misidentified due to its close resemblance with allied species and no other studies have been reported on the anatomical and histochemical characters of this species. This article aims to evaluate the anatomical and histochemical characteristics of various vegetative parts of S. travancoricum. Anatomical and histochemical characters of bark, stem, and leaf were analyzed using standard microscopic and histochemical procedures. S. travancoricum possessed distinct anatomical characters such as, paracytic stomata, arc shaped midrib vasculature, continuous sclerenchymatous sheath around the midrib vascular region, single layer of adaxial palisade layer, presence of druses, and quadrangular cross section contour of stem which could be combined with additional morphological and phytochemical characteristics, relevant for species identification. The bark showed the presence of lignified cells, isolated groups of fibers and sclereids, starch depositions and druses. Stem has quadrangular outline with well-defined periderm. The petiole and the leaf blade have abundance of oil glands and druses with paracytic stomata. The anatomical and histochemical characterization are potential tools for the delineation of confusing taxa and provide substantial evidence to their quality control.


Assuntos
Myrtaceae , Syzygium , Folhas de Planta/anatomia & histologia
8.
Aging Cell ; 22(4): e13782, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36734200

RESUMO

Cardiomyopathy is a progressive disease of the myocardium leading to impaired contractility. Genotoxic cancer therapies are known to be potent drivers of cardiomyopathy, whereas causes of spontaneous disease remain unclear. To test the hypothesis that endogenous genotoxic stress contributes to cardiomyopathy, we deleted the DNA repair gene Ercc1 specifically in striated muscle using a floxed allele of Ercc1 and mice expressing Cre under control of the muscle-specific creatinine kinase (Ckmm) promoter or depleted systemically (Ercc1-/D mice). Ckmm-Cre+/- ;Ercc1-/fl mice expired suddenly of heart disease by 7 months of age. As young adults, the hearts of Ckmm-Cre+/- ;Ercc1-/fl mice were structurally and functionally normal, but by 6-months-of-age, there was significant ventricular dilation, wall thinning, interstitial fibrosis, and systolic dysfunction indicative of dilated cardiomyopathy. Cardiac tissue from the tissue-specific or systemic model showed increased apoptosis and cardiac myocytes from Ckmm-Cre+/- ;Ercc1-/fl mice were hypersensitive to genotoxins, resulting in apoptosis. p53 levels and target gene expression, including several antioxidants, were increased in cardiac tissue from Ckmm-Cre+/- ;Ercc1-/fl and Ercc1-/D mice. Despite this, cardiac tissue from older mutant mice showed evidence of increased oxidative stress. Genetic or pharmacologic inhibition of p53 attenuated apoptosis and improved disease markers. Similarly, overexpression of mitochondrial-targeted catalase improved disease markers. Together, these data support the conclusion that DNA damage produced endogenously can drive cardiac disease and does so mechanistically via chronic activation of p53 and increased oxidative stress, driving cardiac myocyte apoptosis, dilated cardiomyopathy, and sudden death.


Assuntos
Cardiomiopatia Dilatada , Miócitos Cardíacos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Miocárdio/metabolismo , Reparo do DNA
9.
3 Biotech ; 11(6): 289, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34109092

RESUMO

Transcription and translation in eukaryotes are distinct processes of the molecular cascade leading to protein production from genetic material. However, establishing correlation between mRNA expression and protein abundance, the end results of the two processes of central dogma, remains a challenge. For transgenic plants, such correlation between mRNA and protein expression serves as a guide to design the transgene, in particular the choices of promoter and codon usage to ensure stable expression of the target protein in relevant tissues under various stress conditions. To elucidate level of mRNA-protein correlation in a commercial transgenic cotton plant Gossypium hirsutum, Bollgard II® (MON15985), we present the results of Cry1Ac protein expression correlating with corresponding mRNA levels. Protein was quantitated using a home-grown validated ELISA assay with a monoclonal-polyclonal antibody pair, whereas mRNA level was detected by a real-time quantitative PCR assay using standardized reference genes. Our results indicate that protein and mRNA levels are highly correlated in the leaves, but not in squares and stem. The correlations seem to be consistent between young and mature leaves and increase over time of harvesting of samples from months 1-3. These findings demonstrate that transcript level measurement could serve as a proxy to protein abundance for this commercially important cotton species, particularly for leaf tissues which are the most vulnerable organs to cotton bollworms and other pathogens. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02828-2.

10.
Cancer Cell ; 39(2): 193-208.e10, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33357452

RESUMO

Adoptive therapy using chimeric antigen receptor-modified T cells (CAR-T cells) is effective in hematologic but not epithelial malignancies, which cause the greatest mortality. In breast and lung cancer patients, CAR-T cells targeting the tumor-associated antigen receptor tyrosine kinase-like orphan receptor 1 (ROR1) infiltrate tumors poorly and become dysfunctional. To test strategies for enhancing efficacy, we adapted the KrasLSL-G12D/+;p53f/f autochthonous model of lung adenocarcinoma to express the CAR target ROR1. Murine ROR1 CAR-T cells transferred after lymphodepletion with cyclophosphamide (Cy) transiently control tumor growth but infiltrate tumors poorly and lose function, similar to what is seen in patients. Adding oxaliplatin (Ox) to the lymphodepletion regimen activates tumor macrophages to express T-cell-recruiting chemokines, resulting in improved CAR-T cell infiltration, remodeling of the tumor microenvironment, and increased tumor sensitivity to anti-PD-L1. Combination therapy with Ox/Cy and anti-PD-L1 synergistically improves CAR-T cell-mediated tumor control and survival, providing a strategy to improve CAR-T cell efficacy in the clinic.


Assuntos
Inibidores de Checkpoint Imunológico/imunologia , Neoplasias Pulmonares/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Neoplasias/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Humanos , Imunoterapia Adotiva/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/imunologia , Microambiente Tumoral/imunologia
11.
Virol J ; 7: 5, 2010 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-20067630

RESUMO

We undertook one of the most detailed studies on the distribution of alpha2,3 sialic acid (SA)-galactose (gal) (avian type) and alpha2,6SA-gal (human type) receptors on different tissues of chickens, ducks and turkeys of varying age groups. On the tracheal epithelium, all 3 bird species expressed strong positive staining (80-90%) for alpha2,3SA-gal receptors in the 3 different age groups. In addition, a lesser amount of alpha2,6SA-gal receptors (30-90%) were observed with slight differences in distribution with age and species. The epithelium of the small and large intestine of turkeys and ducks showed negligible staining for alpha2,6SA-gal receptors whereas the large intestine consistently showed 40-70% positive staining for alpha2,3SA-gal receptors. In contrast, a greater amount of staining for alpha2,3SA-gal (50-80%) and alpha2,6SA-gal (20-50%) receptors were observed along the epithelium of small and large intestine of chickens. Kidney and esophagus sections from the 3 bird species also expressed both avian and human type receptors. In other tissues examined, brain, breast muscles, bursa, spleen, cecal tonsils and oviduct, human type receptors were absent. Though different viral and receptor components may play roles in successful viral replication and transmission, understanding the receptor types and distribution in different tissues of domestic birds might be good initial tool to understand host factors that promote successful influenza viral infection.


Assuntos
Membrana Celular/química , Galactose/análogos & derivados , Galactose/análise , Variação Genética , Vírus da Influenza A/fisiologia , Receptores Virais/análise , Tropismo Viral , Fatores Etários , Estruturas Animais/química , Animais , Galinhas , Patos , Humanos , Mucosa Intestinal/química , Mucosa Respiratória/química , Perus
12.
Aging (Albany NY) ; 12(6): 4688-4710, 2020 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-32201398

RESUMO

NF-κB is a transcription factor activated in response to inflammatory, genotoxic and oxidative stress and important for driving senescence and aging. Ataxia-telangiectasia mutated (ATM) kinase, a core component of DNA damage response signaling, activates NF-κB in response to genotoxic and oxidative stress via post-translational modifications. Here we demonstrate that ATM is activated in senescent cells in culture and murine tissues from Ercc1-deficient mouse models of accelerated aging, as well as naturally aged mice. Genetic and pharmacologic inhibition of ATM reduced activation of NF-κB and markers of senescence and the senescence-associated secretory phenotype (SASP) in senescent Ercc1-/- MEFs. Ercc1-/Δ mice heterozygous for Atm have reduced NF-κB activity and cellular senescence, improved function of muscle-derived stem/progenetor cells (MDSPCs) and extended healthspan with reduced age-related pathology especially age-related bone and intervertebral disc pathologies. In addition, treatment of Ercc1-/∆ mice with the ATM inhibitor KU-55933 suppressed markers of senescence and SASP. Taken together, these results demonstrate that the ATM kinase is a major mediator of DNA damage-induced, NF-κB-mediated cellular senescence, stem cell dysfunction and aging and thus represents a therapeutic target to slow the progression of aging.


Assuntos
Envelhecimento/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Senescência Celular/fisiologia , Dano ao DNA/fisiologia , NF-kappa B/metabolismo , Células-Tronco/metabolismo , Animais , Células Cultivadas , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout
13.
Mol Cell Biol ; 26(22): 8623-38, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16954381

RESUMO

KAP1/TIF1beta is proposed to be a universal corepressor protein for the KRAB zinc finger protein (KRAB-zfp) superfamily of transcriptional repressors. To characterize the role of KAP1 and KAP1-interacting proteins in transcriptional repression, we investigated the regulation of stably integrated reporter transgenes by hormone-responsive KRAB and KAP1 repressor proteins. Here, we demonstrate that depletion of endogenous KAP1 levels by small interfering RNA (siRNA) significantly inhibited KRAB-mediated transcriptional repression of a chromatin template. Similarly, reduction in cellular levels of HP1alpha/beta/gamma and SETDB1 by siRNA attenuated KRAB-KAP1 repression. We also found that direct tethering of KAP1 to DNA was sufficient to repress transcription of an integrated transgene. This activity is absolutely dependent upon the interaction of KAP1 with HP1 and on an intact PHD finger and bromodomain of KAP1, suggesting that these domains function cooperatively in transcriptional corepression. The achievement of the repressed state by wild-type KAP1 involves decreased recruitment of RNA polymerase II, reduced levels of histone H3 K9 acetylation and H3K4 methylation, an increase in histone occupancy, enrichment of trimethyl histone H3K9, H3K36, and histone H4K20, and HP1 deposition at proximal regulatory sequences of the transgene. A KAP1 protein containing a mutation of the HP1 binding domain failed to induce any change in the histone modifications associated with DNA sequences of the transgene, implying that HP1-directed nuclear compartmentalization is required for transcriptional repression by the KRAB/KAP1 repression complex. The combination of these data suggests that KAP1 functions to coordinate activities that dynamically regulate changes in histone modifications and deposition of HP1 to establish a de novo microenvironment of heterochromatin, which is required for repression of gene transcription by KRAB-zfps.


Assuntos
Proteínas de Ligação a DNA/genética , Heterocromatina/metabolismo , Integrases/genética , Proteínas Repressoras/genética , Transcrição Gênica , Linhagem Celular , Cromatina/metabolismo , Homólogo 5 da Proteína Cromobox , Proteínas de Ligação a DNA/fisiologia , Genes Reporter , Heterocromatina/genética , Histona-Lisina N-Metiltransferase , Histonas/metabolismo , Hormônios/farmacologia , Humanos , Integrases/metabolismo , Proteínas Metiltransferases/genética , RNA Polimerase II/metabolismo , RNA Interferente Pequeno , Proteínas Repressoras/fisiologia , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Transfecção , Proteína 28 com Motivo Tripartido
14.
Geroscience ; 41(4): 455-465, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31468322

RESUMO

An understanding of early-onset mechanisms underlying age-related changes can be obtained by evaluating changes that precede frailty and end of life using histological characterization of age-related lesions. Histopathology-based information as a component of aging studies in mice can complement and add context to molecular, cellular, and physiologic data, but there is a lack of information regarding scoring criteria and lesion grading guidelines. This report describes the validation of a grading system, designated as the geropathology grading platform (GGP), which generated a composite lesion score (CLS) for comparison of histological lesion scores in tissues from aging mice. To assess reproducibility of the scoring system, multiple veterinary pathologists independently scored the same slides from the heart, lung, liver, and kidney from two different strains (C57BL/6 and CB6F1) of male mice at 8, 16, 24, and 32 months of age. There was moderate to high agreement between pathologists, particularly when agreement within a 1-point range was considered. CLS for all organs was significantly higher in older versus younger mice, suggesting that the GGP was reliable for detecting age-related pathology in mice. The overall results suggest that the GGP guidelines reliably distinguish between younger and older mice and may therefore be accurate in distinguishing between experimental groups of mice with more, or less, age-related pathology.


Assuntos
Envelhecimento/patologia , Animais , Rim/patologia , Fígado/patologia , Pulmão/patologia , Camundongos Endogâmicos C57BL , Modelos Animais , Miocárdio/patologia
15.
Sci Transl Med ; 11(503)2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366581

RESUMO

The androgen receptor (AR) is a driver of cellular differentiation and prostate cancer development. An extensive body of work has linked these normal and aberrant cellular processes to mRNA transcription; however, the extent to which AR regulates posttranscriptional gene regulation remains unknown. Here, we demonstrate that AR uses the translation machinery to shape the cellular proteome. We show that AR is a negative regulator of protein synthesis and identify an unexpected relationship between AR and the process of translation initiation in vivo. This is mediated through direct transcriptional control of the translation inhibitor 4EBP1. We demonstrate that lowering AR abundance increases the assembly of the eIF4F translation initiation complex, which drives enhanced tumor cell proliferation. Furthermore, we uncover a network of pro-proliferation mRNAs characterized by a guanine-rich cis-regulatory element that is particularly sensitive to eIF4F hyperactivity. Using both genetic and pharmacologic methods, we demonstrate that dissociation of the eIF4F complex reverses the proliferation program, resulting in decreased tumor growth and improved survival in preclinical models. Our findings reveal a druggable nexus that functionally links the processes of mRNA transcription and translation initiation in an emerging class of lethal AR-deficient prostate cancer.


Assuntos
Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Regulon/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/genética , Proliferação de Células/fisiologia , Humanos , Técnicas In Vitro , Íntrons/genética , Masculino , Camundongos , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Regulon/genética
16.
Cancer J ; 24(2): 78-83, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29601334

RESUMO

Cancer immunotherapy has recently undergone rapid advances and has become an integral part of the treatment armamentarium in various malignancies. However, tissue-based biomarker development in this arena has been slow, and valid biomarker identification to guide immunotherapeutic management is desperately needed. "Liquid" or blood-based biopsies potentially offer more convenient and efficient means to judge the immune milieu of individual patients and identify who will benefit most from immunotherapy. The following review highlights the current literature regarding the application of liquid biopsies to cancer immunotherapy.


Assuntos
Imunoterapia/métodos , Biópsia Líquida/métodos , Neoplasias/terapia , Biomarcadores Tumorais/imunologia , Humanos , Neoplasias/imunologia
17.
Epigenetics Chromatin ; 11(1): 50, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-30170615

RESUMO

BACKGROUND: The long noncoding RNA Xist is critical for initiation and establishment of X-chromosome inactivation during embryogenesis in mammals, but it is unclear whether its continued expression is required for maintaining X-inactivation in vivo. RESULTS: By using an inactive X-chromosome-linked MeCP2-GFP reporter, which allowed us to enumerate reactivation events in the mouse brain even when they occur in very few cells, we found that deletion of Xist in the brain after establishment of X-chromosome inactivation leads to reactivation in 2-5% of neurons and in a smaller fraction of astrocytes. In contrast to global loss of both H3 lysine 27 trimethylation (H3K27m3) and histone H2A lysine 119 monoubiquitylation (H2AK119ub1) we observed upon Xist deletion, alterations in CpG methylation were subtle, and this was mirrored by only minor alterations in X-chromosome-wide gene expression levels, with highly expressed genes more prone to both derepression and demethylation compared to genes with low expression level. CONCLUSION: Our results demonstrate that Xist plays a role in the maintenance of histone repressive marks, DNA methylation and transcriptional repression on the inactive X-chromosome, but that partial loss of X-dosage compensation in the absence of Xist in the brain is well tolerated.


Assuntos
Encéfalo/metabolismo , Repressão Epigenética , RNA Longo não Codificante/genética , Inativação do Cromossomo X , Animais , Metilação de DNA , Código das Histonas , Camundongos , Camundongos Endogâmicos C57BL , RNA Longo não Codificante/metabolismo , Deleção de Sequência
18.
Cancer Discov ; 8(11): 1422-1437, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30181244

RESUMO

CREBBP, encoding an acetyltransferase, is among the most frequently mutated genes in small cell lung cancer (SCLC), a deadly neuroendocrine tumor type. We report acceleration of SCLC upon Crebbp inactivation in an autochthonous mouse model. Extending these observations beyond the lung, broad Crebbp deletion in mouse neuroendocrine cells cooperated with Rb1/Trp53 loss to promote neuroendocrine thyroid and pituitary carcinomas. Gene expression analyses showed that Crebbp loss results in reduced expression of tight junction and cell adhesion genes, including Cdh1, across neuroendocrine tumor types, whereas suppression of Cdh1 promoted transformation in SCLC. CDH1 and other adhesion genes exhibited reduced histone acetylation with Crebbp inactivation. Treatment with the histone deacetylase (HDAC) inhibitor Pracinostat increased histone acetylation and restored CDH1 expression. In addition, a subset of Rb1/Trp53/Crebbp-deficient SCLC exhibited exceptional responses to Pracinostat in vivo Thus, CREBBP acts as a potent tumor suppressor in SCLC, and inactivation of CREBBP enhances responses to a targeted therapy.Significance: Our findings demonstrate that CREBBP loss in SCLC reduces histone acetylation and transcription of cellular adhesion genes, while driving tumorigenesis. These effects can be partially restored by HDAC inhibition, which exhibited enhanced effectiveness in Crebbp-deleted tumors. These data provide a rationale for selectively treating CREBBP-mutant SCLC with HDAC inhibitors. Cancer Discov; 8(11); 1422-37. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1333.


Assuntos
Proteína de Ligação a CREB/fisiologia , Resistencia a Medicamentos Antineoplásicos , Histona Desacetilases/química , Neoplasias Pulmonares/patologia , Proteína do Retinoblastoma/fisiologia , Carcinoma de Pequenas Células do Pulmão/patologia , Proteína Supressora de Tumor p53/fisiologia , Acetilação , Animais , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Inibidores de Histona Desacetilases/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Knockout , Mutação , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/metabolismo , Células Tumorais Cultivadas
19.
J Phys Chem B ; 111(23): 6364-73, 2007 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-17518495

RESUMO

New fluorescent azobenzene dyes and side-chain polymers have been synthesized and characterized and their photophysical properties studied. A series of azobenzene dyes having different fluorophores such as phenol (S1), phenylphenol (S2) and naphthol (S3) incorporated in them were synthesized. S2 had unusually high fluorescence with a quantum yield of phi f = 0.2 recorded in dichloromethane (DCM), whereas S1 and S3 were found to be weakly fluorescent. The azobenzene dyes were converted into methacrylate monomers having short ethyleneoxy spacers and then free radically polymerized. Phenylphenol-based azobenzene polymer (P2) continued to show fluorescence, whereas fluorescence was completely quenched in the case of phenol (P1)- and naphthol (P3)-based polymers. Phenylphenol, though twisted in the ground state is known to have a more planar geometry in the excited state--a factor that enables it to retain its fluorescence behavior even when it is incorporated as part of an azobenzene unit. In contrast, naphthol, which is a better fluorophore compared to phenylphenol, loses much of its emissive behavior upon coupling to the azobenzene unit. The extent of trans to cis photoisomerization in solution was very low (approximately 17%) for P2 after 30 min of continuous irradiation using 365 nm light, in contrast to approximately 40% for P1 under identical conditions. This is attributed to the steric repulsion brought about by the bulky phenylphenol units that restrict rotation. A 2-fold enhancement in fluorescence emission was observed for P2 upon irradiation by UV light at 360 nm, which relaxed to the original intensity in about 7 day's time. The higher emission of the cis azobenzenes is generally attributed to an inhibition of photoinduced electron transfer (PET) mechanism. The emission of P2 showed a concentration dependence which increased initially and then decreased in intensity with the formation of a new red-shifted peak at higher concentration due to aggregation. Irradiation of the fluorescence quenched highly concentrated (1 x 10(-3) M) sample of P2 showed an enhancement in emission from aggregates at 532 nm.

20.
J Environ Biol ; 28(3): 591-5, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18380080

RESUMO

Quality of water is an important criterion for evaluating the suitability of water for irrigation and drinking. In the present study the analysis of water samples from different sources like open wells, bore wells, farm ponds and streams/rivers of twenty villages of Bantwal taluk of Dakshina Kannada district, South-western Kamataka has been carried out. The physico-chemical characteristics of this water showed that it is suitable for irrigation and agricultural purposes.


Assuntos
Agricultura , Água Doce/análise , Abastecimento de Água/análise , Cálcio/análise , Carbonatos/análise , Cloretos/análise , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Índia , Magnésio/análise , Nitratos/análise , Potássio/análise , Salinidade , Sódio/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA