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1.
Anim Genet ; 51(4): 617-619, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32432791

RESUMO

Canine hip dysplasia is characterized by poor hip joint conformation and laxity. The disease is a complex trait influenced by both genetics and environment. Diagnosis and quantification of hip dysplasia are performed by radiographic examination of the hip joint and the diagnosis is used for making breeding decisions in many breeds. A prognostic genetic test (the Dysgen test) based on seven associated SNPs has been developed in a study based on Spanish Labrador Retrievers. In our study this test has been evaluated in 39 Danish Labrador Retrievers with known radiographic hip score: 14 with hip dysplasia (grade D or E) and 25 without hip dysplasia (grade A or B). There was no significant correlation between the Dysgen test results and the radiographic hip status (P = 0.3203) in these dogs, indicating that Dysgen test results obtained for Danish Labrador Retrievers have no prognostic value.


Assuntos
Testes Genéticos/veterinária , Displasia Pélvica Canina/genética , Polimorfismo de Nucleotídeo Único , Radiografia/veterinária , Animais , Dinamarca , Cães , Testes Genéticos/métodos , Especificidade da Espécie
2.
J Phys Chem A ; 124(22): 4471-4483, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32401028

RESUMO

Parahydrogen (pH2) quantum solids are excellent matrix isolation hosts for studying the rovibrational dynamics and nuclear spin conversion (NSC) kinetics of molecules containing indistinguishable nuclei with nonzero spin. The relatively slow NSC kinetics of propyne (CH3CCH) isolated in solid pH2 is employed as a tool to assign the rovibrational spectrum of propyne in the 600-7000 cm-1 region. Detailed analyses of a variety of parallel (ΔK = 0) and perpendicular (ΔK=±1) bands of propyne indicate that the end-over-end rotation of propyne is quenched, but K rotation of the methyl group around the C3 symmetry axis still persists. However, this single-axis K rotation is significantly hindered for propyne trapped in solid pH2 such that the energies of the K rotational states do not obey simple energy-level expressions. The NSC kinetics of propyne follows first-order reversible kinetics with a 287(7) min effective time constant at 1.7 K. Intensity-intensity correlation plots are used to determine the relative line strengths of individual ortho- and para-propyne rovibrational transitions, enabling an independent estimation of the ground vibrational state effective A″ constant of propyne.

3.
Int J Pharm ; 563: 437-444, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30980887

RESUMO

The development of an injectable biomaterial that supports cell survival and maintains or promotes nucleus pulposus (NP) phenotype could aid delivery of cells to degenerated NPs causing low back pain. Mesenchymal cells were loaded and grown in a synthetic peptide gel, PuraMatrix®. Cells were observed within the gels over 0-28 days, and accumulation of glycosaminoglycans were detected by histological staining. The mechanical properties of the cell-loaded constructs, and the change of the mechanical properties were studied using stress relaxation of the gels under compression and confinement. The PuraMatrix® gel was shown to relax fast on compression indicating that the fluid could easily flow out of the gel, and thus indicating the presence of large pores/voids. The presence of these pores/voids was further supported by high mobility of dextran molecules, determined using fluorescence recovery after photo bleaching. The stress required to deform the cell-loaded constructs to a specific strain increases at day 21, at which point the presence of glycosaminoglycans within the cell-loaded constructs was also observed. The results provide evidence of changes in mechanical properties of the PuraMatrix® matrix upon excretion of the extracellular matrix by the cells.


Assuntos
Matriz Extracelular/metabolismo , Glicosaminoglicanos/metabolismo , Hidrogéis , Células-Tronco Mesenquimais/metabolismo , Peptídeos , Células Cultivadas , Humanos , Reologia , Estresse Mecânico
4.
Nature ; 561(7721): E2, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29930351

RESUMO

Change history: In this Letter, the Acknowledgements section should have included the following sentence: "The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.". This omission has been corrected online.

5.
Nature ; 556(7702): 469-472, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29695849

RESUMO

Massive galaxy clusters have been found that date to times as early as three billion years after the Big Bang, containing stars that formed at even earlier epochs1-3. The high-redshift progenitors of these galaxy clusters-termed 'protoclusters'-can be identified in cosmological simulations that have the highest overdensities (greater-than-average densities) of dark matter4-6. Protoclusters are expected to contain extremely massive galaxies that can be observed as luminous starbursts 7 . However, recent detections of possible protoclusters hosting such starbursts8-11 do not support the kind of rapid cluster-core formation expected from simulations 12 : the structures observed contain only a handful of starbursting galaxies spread throughout a broad region, with poor evidence for eventual collapse into a protocluster. Here we report observations of carbon monoxide and ionized carbon emission from the source SPT2349-56. We find that this source consists of at least 14 gas-rich galaxies, all lying at redshifts of 4.31. We demonstrate that each of these galaxies is forming stars between 50 and 1,000 times more quickly than our own Milky Way, and that all are located within a projected region that is only around 130 kiloparsecs in diameter. This galaxy surface density is more than ten times the average blank-field value (integrated over all redshifts), and more than 1,000 times the average field volume density. The velocity dispersion (approximately 410 kilometres per second) of these galaxies and the enormous gas and star-formation densities suggest that this system represents the core of a cluster of galaxies that was already at an advanced stage of formation when the Universe was only 1.4 billion years old. A comparison with other known protoclusters at high redshifts shows that SPT2349-56 could be building one of the most massive structures in the Universe today.

6.
Cytokine ; 102: 131-140, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28807497

RESUMO

Early acting cytokines and growth factors such as those of the CD131 ßc subunit, may offer an alternative method to the current use of antibiotics and chemicals such as anthelmintics in maintaining Porcine (Po) health. Thus far, the recombinant Po (rPo) Granulocyte-macrophage colony-stimulating factor (GM-CSF), rPo interleukin-3 (IL-3) and rPo interleukin-5 (IL-5) proteins have been identified and cloned and the biological activity of each cytokine has been confirmed in vitro, however, in vivo immune system regulation and hematopoietic stem cell (HSC) augmentation are regulated by numerous cytokines and cellular signals within the bone marrow (BM) niche. In order to quantify the use of recombinant cytokines in augmenting the immune response, it is necessary to determine the stages of hematopoiesis induced by each cytokine and possible areas of synergy requiring further investigation. Here we used the chemotherapeutic agent 5-fluorouracil (5-FU), to chemically induce a state of myelosuppression in young pigs. This allowed for the monitoring of both the autologous BM reconstitution and recombinant cytokine induced BM repopulation, precursor cell proliferation and cellular differentiation. The recombinant cytokines PoGM-CSF, PoIL-3 and PoIL-5 were administered by intramuscular injections (i.m.) following confirmation of 5-FU induced leukocytopenia. Blood and BM samples were collected and then analysed for cell composition. Statistically significant results were observed in several blood cell populations including eosinophils for animals treated with rPoIL-5, rPoGM-CSF and basophils for animals treated with rPoIL-3. BM analysis of CD90+ and CD172a+ cells confirmed myelosuppression in week one with significant results observed between rPoIL-3 and the 5-FU control group in week two and for the rPoGM-CSF group in week three. These results have demonstrated the effects of each of these rPo cytokines within the hematopoietic processes of the pig and may demonstrate similar outcomes in other mammalian models including human.


Assuntos
Subunidade beta Comum dos Receptores de Citocinas/metabolismo , Citocinas/imunologia , Sus scrofa/imunologia , Animais , Antígenos CD/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Subunidade beta Comum dos Receptores de Citocinas/química , Citocinas/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hematopoese/efeitos dos fármacos , Hematopoese/imunologia , Imunização/métodos , Imunização/veterinária , Interleucina-3/imunologia , Interleucina-3/farmacologia , Interleucina-5/imunologia , Interleucina-5/farmacologia , Subunidades Proteicas , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Antígenos Thy-1/metabolismo
7.
Science ; 358(6370): 1570-1574, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29038375

RESUMO

On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe.

8.
Curr Microbiol ; 69(5): 681-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24972665

RESUMO

Artificial climbing walls represent a unique indoor environment in which humans interact closely with a variety of surface types. Climbing wall holds may mediate transmission of organisms between individuals, and yet there are no studies that identify microorganisms present on these surfaces. In the current study, the microorganisms found on climbing wall holds were characterized by analysis of amplified SSU rRNA gene sequences. In contrast to many other studies of built environments, the majority of microorganisms on holds were most closely related to microbes annotated as being recovered from environmental sources, such as soil, with human skin also representing an important source. Regional patterns were evident as rRNA gene sequences from the marine cyanobacterium Prochlorococcus were abundant in gyms found within 16 km of the ocean. Enterobacteriaceae were present on 100 % of holds surveyed, and the members detected are commonly associated with fecal matter.


Assuntos
Bactérias/classificação , Bactérias/genética , Biota , Microbiologia Ambiental , Análise por Conglomerados , DNA Ribossômico/química , DNA Ribossômico/genética , Humanos , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esportes
9.
Oncogene ; 33(33): 4213-25, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24077289

RESUMO

Estrogen receptor ß (ERß) is emerging as a critical factor in understanding prostate cancer biology. Although reduced in prostate cancer above Gleason grade 3, ERß is a potential drug target at the initial stage of the disease. In human prostate cancer cells, we found that ERß causes apoptosis by increasing the expression of pro-apoptotic factor p53-upregulated modulator of apoptosis (PUMA), independent of p53, but dependent on the forkhead transcription factor class-O family member, FOXO3a. FOXO3a has previously been shown to induce PUMA after growth factor withdrawal and inhibition of the Akt pathway. Surprisingly, the phosphorylation of FOXO3a remained unchanged, while the mRNA and total protein levels of FOXO3a were increased in response to ERß expression or treatment of PC3, 22Rv1 and LNCaP cells with the ERß-specific ligands 3ß-Adiol (5α-androstane-3ß,17ß-diol), DPN (diarylpropionitrile) or 8ß-VE2 (8-vinylestra-1,3,5 (10)-triene-3,17ß-diol). Knockdown of FOXO3a or ERß expression abolished the increase of PUMA in response to 3ß-Adiol in LNCaP and PC3 cells, suggesting that FOXO3a mediates the apoptotic effect of 3ß-Adiol-activated ERß. Moreover, the ventral prostate of ERß-/- mice had decreased expression of FOXO3a and PUMA compared with the ERß+/+ mice, indicating a relationship between ERß and FOXO3a expression. The regulation of FOXO3a by ERß in normal basal epithelial cells indicates a function of ERß in cell differentiation and maintenance of cells in a quiescent state. In addition, the expression of ERß, FOXO3a and PUMA is comparable and higher in benign prostatic hyperplasia than in prostate cancer Gleason grade 4 or higher, where there is substantial loss of ERß, FOXO3a and PUMA. We conclude that ERß induces apoptosis of prostate cancer cells by increasing transcription of FOXO3a, leading to an increase of PUMA and subsequent triggering of apoptosis via the intrinsic pathway involving caspase-9. Furthermore, we conclude that ligands specifically activating ERß could be useful pharmaceuticals in the treatment of prostate cancer.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Receptor beta de Estrogênio/fisiologia , Fatores de Transcrição Forkhead/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Linhagem Celular Tumoral , Proteína Forkhead Box O3 , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Nus , Gradação de Tumores , Transplante de Neoplasias , Neoplasias da Próstata/patologia , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
10.
Plant Biol (Stuttg) ; 15(6): 1025-32, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23573946

RESUMO

Post-harvest storage is largely limited by fruit softening, a result of cell wall degradation. Pectin methylesterase (PE) (EC 3.1.1.11) is a major hydrolase responsible for pectin de-esterification in the cell wall, a response to fruit ripening. Two major PE isoforms, PE1 and PE2, have been isolated from tomato (Solanum lycopersicon) pericarp tissue and both have previously been down-regulated using antisense suppression. In this paper, PE1 and PE2 double antisense tomato plants were successfully generated through crossing the two single antisense lines. In the double antisense fruit, approximately 10% of normal PE activity remained and ripening associated pectin de-esterification was almost completely blocked. However, double antisense fruit softened normally during ripening. In tomato fruit, the PE1 isoform was found to contribute little to total PE activity and have little effect on the degree of esterification of pectin. In contrast, the other dominant fruit isoform, PE2, has a major impact on de-esterification of total pectin. PE2 appears to act on non-CDTA-soluble pectin during ripening and on CDTA-soluble pectin before the start of ripening in a potentially block-wise fashion.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Frutas/enzimologia , Regulação da Expressão Gênica de Plantas , Pectinas/metabolismo , Solanum lycopersicum/enzimologia , Hidrolases de Éster Carboxílico/genética , Parede Celular/metabolismo , Regulação para Baixo , Frutas/genética , Frutas/crescimento & desenvolvimento , Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Inativação Gênica , Isoenzimas/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Ácidos Urônicos/análise , Ácidos Urônicos/metabolismo
11.
Vet Pathol ; 50(5): 909-13, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23381923

RESUMO

A 9-year-old cynomolgus monkey (Macaca fascicularis) infected orally with bovine spongiform encephalopathy (BSE) was presented for necropsy following euthanasia 4 years post infection (p.i.). This macaque R984 was exposed to a BSE dose that causes a simian form of variant Creutzfeldt-Jakob disease (vCJD) within 5 years p.i. in other macaques. All orally BSE-infected macaques developed a significant weight gain within the first 2 years p.i. compared with non-BSE-infected age- and sex-matched control animals, suggesting increased risk of type 2 diabetes (T2D). In contrast, macaque R984 developed rapid weight loss, hyperglycemia, and glucosuria and had to be euthanatized 4 years p.i. before clinical signs of vCJD. Pancreas histopathological evaluation revealed severe islet degeneration but, remarkably, no islet amyloid deposits were present. Immunostaining of pancreas sections for insulin and glucagon confirmed the loss of endocrine cells. In addition, prions were present in the adenohypophysis but not in other areas of the brain, indicating centripetal prion spread from the gut during the preclinical phase of BSE infection. Plasma glucose and insulin concentrations of macaque R984 became abnormal with age and resembled T2D. This unusual case of spontaneous T2D in the absence of islet amyloid deposits could have been due to early prion spread from the periphery to the endocrine system or could have occurred spontaneously.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Encefalopatia Espongiforme Bovina/complicações , Macaca fascicularis , Doenças dos Macacos/patologia , Obesidade/complicações , Animais , Glicemia/metabolismo , Peso Corporal , Bovinos , Diabetes Mellitus Tipo 2/etiologia , Feminino , Técnicas Histológicas/veterinária , Insulina/sangue , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Pâncreas/patologia , Fatores Sexuais
12.
Acta Gastroenterol Belg ; 75(3): 300-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23082699

RESUMO

Bad breath is a condition that has health and social implications. This paper provides a comprehensive review of the classification of halitosis, it's etiology, it's prevalence, diagnosis and treatment strategies for the condition. Halitosis is affecting about 25-30% of world's population. It includes categories of genuine halitosis, pseudo-halitosis and halitophobia. It is believed that in 80-90% of cases halitosis origins in the oral cavity and the most common causes are: gingival pathologies, caries and poor oral hygiene. Extraoral sources of halitosis are responsible for 10-20% of all cases and are caused by poor diet, alcohol abuse, tobacco smoking, certain drugs and diseases of other parts of digestive tract as well as some systemic conditions. Diagnostics of halitosis includes subjective methods (examiner's sense of smell) and objective methods (instrumental analysis). Simple, subjective examination is considered a "golden standard" in clinical practice. In case of pathological halitosis identifying the direct cause of halitosis is essential. After excluding, or after successful treatment, of all oral pathologies, in case of remaining fetor ex ore identification and treatment of halitosis often requires multidisciplinary approach. Many unknowns remain in causes and mechanisms of halitosis. It can significantly impair quality of life, social interactions, lead directly to depression,low self-esteem or other mood disorders, therefore it is important to properly identify, treat and continue research on halitosis.


Assuntos
Halitose , Testes Respiratórios , Halitose/diagnóstico , Halitose/etiologia , Halitose/microbiologia , Halitose/fisiopatologia , Halitose/terapia , Helicobacter pylori/isolamento & purificação , Humanos , Relações Interpessoais , Estilo de Vida , Qualidade de Vida
13.
Xenotransplantation ; 15(4): 257-67, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18957048

RESUMO

BACKGROUND: Porcine dendritic cells (DC) are likely to be pivotal cells in the initiation of stimulatory and potential tolerogenic responses to xenoantigens, however, there are limited studies characterizing these antigen presenting cells. METHODS: Porcine PBMC (CD172a(+)) were cultured with GM-CSF and IL-4 and phenotype and functional capabilities assessed. Lipopolysaccharide (LPS), IL-10, and IL-3 were added to the GM-CSF/IL-4 DC cultures to determine phenotypic and functional changes. Quantitative real-time polymerase chain reaction (PCR) for key cytokines was performed and the modified porcine DC were further assessed by primary mixed lymphocyte reaction to determine the effect of LPS, IL-10, and IL-3 on stimulatory capability. RESULTS: Porcine PBMC (CD172(+)) cultured with GM-CSF and IL-4 produced cells with DC morphology, which were major histocompatability complex (MHC) class II(+), CD14(-/lo), and CD1a(lo). Addition of IL-10 or IL-3 to GM-CSF/IL-4 DC cultures produced cells with lower levels of MHC class II and higher levels of antigen uptake consistent with less mature DC. Quantitative real-time PCR of DC showed the addition of IL-10 induced an increase in IL-10 mRNA, no detectable IL-12, and reduced IL-6 mRNA. The addition of IL-3 to DC cultures decreased IL-12, IL-6 and tumor necrosis factor (TNF), with no change in IL-10 mRNA. GM-CSF/IL-4 DC induced strong human lymphocyte proliferation, compared with significantly reduced stimulatory capacity induced by IL-10 and IL-3 treated DC cultures. CONCLUSIONS: The profound effect on differential DC cytokine profile and reduced human anti-pig responses has important therapeutic implications in xenotransplantation. The mechanism of altered regulation warrants further investigation.


Assuntos
Citocinas/genética , Células Dendríticas/imunologia , Transplante Heterólogo/imunologia , Animais , Células Dendríticas/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Tolerância Imunológica , Técnicas In Vitro , Interleucina-10/farmacologia , Interleucina-3/farmacologia , Interleucina-4/farmacologia , Lipopolissacarídeos/farmacologia , Ativação Linfocitária , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes , Suínos , Porco Miniatura , Linfócitos T/imunologia
14.
J Steroid Biochem Mol Biol ; 112(4-5): 171-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18955141

RESUMO

This study investigates the importance of the intracellular ratio of the two estrogen receptors ERalpha and ERbeta for the ultimate potential of the phytoestrogens genistein and quercetin to stimulate or inhibit cancer cell proliferation. This is of importance because (i) ERbeta has been postulated to play a role in modulating ERalpha-mediated cell proliferation, (ii) genistein and quercetin may be agonists for both receptor types and (iii) the ratio of ERalpha to ERbeta is known to vary between tissues. Using human osteosarcoma (U2OS) ERalpha or ERbeta reporter cells it was shown that compared to estradiol (E2), genistein and quercetin have not only a relatively greater preference for ERbeta but also a higher maximal potential for activating ERbeta-mediated gene expression. Using the human T47D breast cancer cell line with tetracycline-dependent ERbeta expression (T47D-ERbeta), the effect of a varying intracellular ERalpha/ERbeta ratio on E2- or pythoestrogen-induced cell proliferation was characterised. E2-induced proliferation of cells in which ERbeta expression was inhibited was similar to that of the T47D wild type cells, whereas this E2-induced cell proliferation was no longer observed when ERbeta expression was increased. With increased expression of ERbeta the phytoestrogen-induced cell proliferation was also reduced. These results point at the importance of the cellular ERalpha/ERbeta ratio for the ultimate effect of (phyto)estrogens on cell proliferation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Receptor alfa de Estrogênio/fisiologia , Receptor beta de Estrogênio/fisiologia , Genisteína/farmacologia , Fitoestrógenos/farmacologia , Quercetina/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Estradiol/farmacologia , Receptor beta de Estrogênio/antagonistas & inibidores , Humanos , Tetraciclina/farmacologia
15.
Oncogene ; 27(7): 1019-32, 2008 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-17700529

RESUMO

Transcriptional effects of estrogen result from its activation of two estrogen receptor (ER) isoforms; ERalpha that drives proliferation and ERbeta that is antiproliferative. Expression of ERbeta in xenograft tumors from the T47D breast cancer cell line reduces tumor growth and angiogenesis. If ERbeta can halt tumor growth, its introduction into cancers may be a novel therapeutic approach to the treatment of estrogen-responsive cancers. To assess the complete impact of ERbeta on transcription, we have made a full transcriptome analysis of ERalpha- and ERbeta-mediated gene regulation in T47D cell line with Tet-Off regulated ERbeta expression. Of the 35 000 genes and transcripts analysed, 4.1% (1434) were altered by ERalpha activation. Tet withdrawal and subsequent ERbeta expression inhibited the ERalpha regulation of 998 genes and, in addition, altered expression of 152 non-ERalpha-regulated genes. ERalpha-induced and ERbeta-repressed genes were involved in proliferation, steroid/xenobiotic metabolism and ion transport. The ERbeta repressive effect was further confirmed by proliferation assays, where ERbeta was shown to completely oppose the ERalpha-E2 induced proliferation. Additional analysis of ERbeta with a mutated DNA-binding domain revealed that this mutant, at least for a quantity of genes, antagonizes ERalpha even more strongly than ERbeta wt. From an examination of the genes regulated by ERalpha and ERbeta, we suggest that introduction of ERbeta may be an alternative therapeutic approach to the treatment of certain cancers.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Estradiol/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrogênios/farmacologia , Feminino , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Transcrição Gênica
16.
Fungal Genet Biol ; 44(8): 799-807, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17300967

RESUMO

We investigated the sexual reproductive mode of the two most important etiological agents of soybean sudden death syndrome, Fusarium tucumaniae and Fusarium virguliforme. F. tucumaniae sexual crosses often were highly fertile, making it possible to assign mating type and assess female fertility in 24 South American isolates. These crosses produced red perithecia and oblong-elliptical ascospores, as is typical for sexual members of the F. solani species complex. Genotyping of progeny from three F. tucumaniae crosses confirmed that sexual recombination had occurred. In contrast, pairings among 17 U.S. F. virguliforme isolates never produced perithecia. Inter-species crosses between F. tucumaniae and F. virguliforme, in which infertile perithecia were induced only in one of the two F. tucumaniae mating types, suggest that all U.S. F. virguliforme isolates are of a single mating type. We conclude that the F. tucumaniae life cycle in S. America includes a sexual reproductive mode, and thus this species has greater potential for rapid evolution than the F. virguliforme population in the U.S., which may be exclusively asexual.


Assuntos
Fusarium/crescimento & desenvolvimento , Fusarium/fisiologia , Glycine max/microbiologia , Doenças das Plantas/microbiologia , Cruzamentos Genéticos , DNA Fúngico/genética , Fusarium/ultraestrutura , Genótipo , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase , Esporos Fúngicos/citologia , Esporos Fúngicos/ultraestrutura
17.
Exp Hematol ; 35(1): 171-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17198886

RESUMO

OBJECTIVES: The isolation of porcine hematopoietic stem cells (HSC) would be an important step toward development of porcine-to-human chimerism for induction of tolerance in clinical xenotransplantation. CD34 is a common marker of HSC and has not been developed as a marker in pigs. In this study we have generated and characterized a monoclonal antibody (mAb) that identifies porcine CD34 on a subset of porcine bone marrow (BM) stem/progenitor cells. METHODS: The porcine CD34 gene was cloned and a recombinant protein produced. An anti-porcine CD34 mAb was produced that could detect both the recombinant protein and a subset of porcine BM cells. The CD34(+) cells were phenotyped by lineage and HSC associated markers. Furthermore, the CD34(+) cells were analyzed by colony-forming unit (CFU) assay. RESULTS: Two splice variants of the porcine CD34 gene were cloned and a recombinant protein produced for mAb production. The mAb developed can detect both the recombinant protein and the native CD34 protein on a range of pig tissues, including BM. This subset of BM cells was negative for hematopoietic lineage makers, including CD3, CD14, and CD21 and positive for other known porcine HSC markers, including CD90, CD172a, histocompatibility complex (MHC) class I, and MHC class II. Moreover, the CD34(+) BM cells were enriched for multilineage progenitor cells as determined by CFU assay. CONCLUSIONS: Similar to human and mouse CD34, pig CD34 detects a subset of BM progenitor cells. This mAb will now provide a means for isolating porcine CD34(+) cells to be further analyzed for HSC activity and to assess their potential to develop pig-to-human chimeras to induce xenograft tolerance.


Assuntos
Anticorpos Monoclonais , Antígenos CD34/imunologia , Separação Celular/métodos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Animais , Antígenos CD34/genética , Células da Medula Óssea , Técnicas de Cultura de Células , Clonagem Molecular , Ensaio de Unidades Formadoras de Colônias , Imunofenotipagem/métodos , Suínos
18.
Histol Histopathol ; 19(2): 337-47, 2004 04.
Artigo em Inglês | MEDLINE | ID: mdl-15024695

RESUMO

During accelerated vascular remodeling such as in atherosclerosis, the composition of the extracellular matrix becomes altered. The matrix components of the diseased artery influence cellular processes such as adhesion, migration and proliferation. Furthermore, in atherosclerosis, the inability of the cells within the lesion to produce a mechanically stable matrix may lead to plaque rupture. In this immunohistochemical study of atherosclerotic mice aorta, we have reviewed the presence of ECM components with roles in maintaining tissue structure and function. These components include osteopontin and COMP as well as the leucine rich repeats proteins decorin, PRELP, and fibromodulin. Immunohistochemistry demonstrated presence of osteopontin, COMP, decorin, PRELP and fibromodulin in lesion areas of ApoE/LDLr deficient mice. Some advanced lesions exhibited areas of cartilage-like morphology and were shown to represent cartilage by their content of the cartilage specific proteins collagen II and aggrecan. The results suggest that cartilage-associated cell/collagen binding ECM proteins may be involved in the pathogenesis of atherosclerosis.


Assuntos
Aorta/metabolismo , Apolipoproteínas E/metabolismo , Apolipoproteínas E/fisiologia , Arteriosclerose/metabolismo , Matriz Extracelular/metabolismo , Receptores de LDL/fisiologia , Animais , Aorta/patologia , Apolipoproteínas E/genética , Western Blotting , Cartilagem/metabolismo , Divisão Celular , Colágeno/química , Proteínas da Matriz Extracelular/metabolismo , Fibromodulina , Regulação da Expressão Gênica , Glicoproteínas/metabolismo , Imuno-Histoquímica , Proteínas Matrilinas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteopontina , Proteoglicanas/metabolismo , Receptores de LDL/genética , Sialoglicoproteínas/metabolismo , Fatores de Tempo
19.
Appl Environ Microbiol ; 68(9): 4328-33, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200283

RESUMO

Anhydrobiotic engineering aims to increase the level of desiccation tolerance in sensitive organisms to that observed in true anhydrobiotes. In addition to a suitable extracellular drying excipient, a key factor for anhydrobiotic engineering of gram-negative enterobacteria seems to be the generation of high intracellular concentrations of the nonreducing disaccharide trehalose, which can be achieved by osmotic induction. In the soil bacterium Pseudomonas putida KT2440, however, only limited amounts of trehalose are naturally accumulated in defined high-osmolarity medium, correlating with relatively poor survival of desiccated cultures. Based on the enterobacterial model, it was proposed that increasing intracellular trehalose concentration in P. putida KT2440 should improve survival. Using genetic engineering techniques, intracellular trehalose concentrations were obtained which were similar to or greater than those in enterobacteria, but this did not translate into improved desiccation tolerance. Therefore, at least for some populations of microorganisms, trehalose does not appear to provide full protection against desiccation damage, even when present at high concentrations both inside and outside the cell. For P. putida KT2440, it was shown that this was not due to a natural limit in desiccation tolerance since successful anhydrobiotic engineering was achieved by use of a different drying excipient, hydroxyectoine, with osmotically preconditioned bacteria for which 40 to 60% viability was maintained over extended periods (up to 42 days) in the dry state. Hydroxyectoine therefore has considerable potential for the improvement of desiccation tolerance in sensitive microorganisms, particularly for those recalcitrant to trehalose.


Assuntos
Diamino Aminoácidos/farmacologia , Pseudomonas putida/efeitos dos fármacos , Trealose/farmacologia , Diamino Aminoácidos/metabolismo , Dessecação , Escherichia coli/genética , Engenharia Genética , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Concentração Osmolar , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Substâncias Protetoras/farmacologia , Pseudomonas putida/genética , Pseudomonas putida/metabolismo
20.
Genome Biol ; 2(6): REVIEWS3008, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11423015

RESUMO

SUMMARY: In recent years, our understanding of macromolecular transport processes across the nuclear envelope has grown dramatically, and a large number of soluble transport receptors mediating either nuclear import or nuclear export have been identified. Most of these receptors belong to one large family of proteins, all of which share homology with the protein import receptor importin beta (also named karyopherin beta). Members of this family have been classified as importins or exportins on the basis of the direction they carry their cargo. To date, the family includes 14 members in the yeast Saccharomyces cerevisiae and at least 22 members in humans. Importins and exportins are regulated by the small GTPase Ran, which is thought to be highly enriched in the nucleus in its GTP-bound form. Importins recognize their substrates in the cytoplasm and transport them through nuclear pores into the nucleus. In the nucleoplasm, RanGTP binds to importins, inducing the release of import cargoes. In contrast, exportins interact with their substrates only in the nucleus in the presence of RanGTP and release them after GTP hydrolysis in the cytoplasm, causing disassembly of the export complex. Thus, common features of all importin-beta-like transport factors are their ability to shuttle between the nucleus and the cytoplasm, their interaction with RanGTP as well as their ability to recognize specific transport substrates.


Assuntos
Proteínas Nucleares/fisiologia , Transporte Ativo do Núcleo Celular , Evolução Molecular , Proteínas Fúngicas/fisiologia , Humanos , Carioferinas , Modelos Biológicos , Proteínas Nucleares/química , Proteínas Nucleares/genética , Estrutura Secundária de Proteína , Sequências Repetitivas de Aminoácidos , Proteína ran de Ligação ao GTP/fisiologia
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