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1.
Sci Rep ; 11(1): 20489, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650177

RESUMO

Certification of quantum nonlocality plays a central role in practical applications like device-independent quantum cryptography and random number generation protocols. These applications entail the challenging problem of certifying quantum nonlocality, something that is hard to achieve when the target quantum state is only weakly entangled, or when the source of errors is high, e.g. when photons propagate through the atmosphere or a long optical fiber. Here we introduce a technique to find a Bell inequality with the largest possible gap between the quantum prediction and the classical local hidden variable limit for a given set of measurement frequencies. Our method represents an efficient strategy to certify quantum nonlocal correlations from experimental data without requiring extra measurements, in the sense that there is no Bell inequality with a larger gap than the one provided. Furthermore, we also reduce the photodetector efficiency required to close the detection loophole. We illustrate our technique by improving the detection of quantum nonlocality from experimental data obtained with weakly entangled photons.

2.
Semergen ; 45(7): 434-440, 2019 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-30594501

RESUMO

OBJECTIVE: To detect doubts and training needs in an urban health and family doctor training centre during the usual practice. MATERIAL AND METHODS: A cross-sectional descriptive study was conducted for one month in an urban health centre in Madrid. Family doctors were interviewed after their daily clinics about the doubts they had identified, choosing two of them. Unresolved questions were grouped by subject and according to the current taxonomies. A teaching program was then developed to tackle them. RESULTS: Out of a total 21 physicians of the centre, 19 attended 10,678 patients during the period. The doubt detection rate was 0.44 doubts for every 10 patients attended. Of the 384 questions chosen, 83.34% were clinical and 16.66% were non-clinical. Just over half (51.2%) of these were still unresolved 15days later the consultation event. The main methods for their resolution were using the scientific bases on the internet (mainly PubMed, UpToDate and Clinical Practice Guidelines; 38%), followed by consultation with other colleagues (34.9%). CONCLUSIONS: Most of the doubts generated during clinics were clinical, although there is a significant burden of bureaucratic questions. More than half of the doubts are not resolved during the consultation or within the following 15days. The scientific databases on the internet are the main sources of information, although consulting other colleagues was often used as well. Additional time for dealing with patients and enhanced access to solve complex questions should be available to improve the success rate.


Assuntos
Médicos de Família/psicologia , Atenção Primária à Saúde/organização & administração , Serviços Urbanos de Saúde/organização & administração , Adulto , Estudos Transversais , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Médicos de Família/educação , Espanha
3.
Clin Microbiol Infect ; 24(6): 630-634, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28970161

RESUMO

OBJECTIVE: To assess the association of survival and treatment with colistin and tigecycline in critically ill patients with carbapenem-resistant Acinetobacter baumannii bacteraemia. METHODS: An observational cohort study was carried out. Targeted therapy consisted of monotherapy with colistin (9 million UI/day) or combined therapy with colistin and tigecycline (100 g/day). The primary outcome was 30-day crude mortality. The association between combined targeted therapy and mortality was controlled for empirical therapy with colistin, propensity score of combined therapy and other potential confounding variables in a multivariate Cox regression analysis. RESULTS: A total of 118 cases were analysed. Seventy-six patients (64%) received monotherapy and 42 patients (36%) received combined therapy. The source of bacteraemia was primary in 18% (21/118) of the patients, ventilator-associated pneumonia in 64% (76/118) and other sources in 14% (16/118). The 30-day crude mortality rate was 62% (42/76) for monotherapy and 57% (24/42) for combined therapy. The variables associated with 30-day crude mortality were: Charlson index (hazard ratio (HR) 1.16, 95% CI 1.02-1.32; p 0.028), empirical therapy with colistin (HR 2.25, 95% CI 1.33-3.80; p 0.003) and renal dysfunction before treatment (HR 1.91, 95% CI 1.01-3.61; p 0.045). Combined targeted therapy was not associated with lower adjusted 30-day crude mortality (adjusted HR 1.29, 95% CI 0.64-2.58; p 0.494). CONCLUSIONS: Combined targeted therapy with high-dose colistin and standard dose tigecycline was not associated with lower crude mortality of bacteraemia due to carbapenem-resistant A. baumannii in critically ill patients. TRIAL REGISTRATION: Registered in ClinicalTrials.gov. Identifier: NCT02573064.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Bacteriemia/tratamento farmacológico , Colistina/administração & dosagem , Minociclina/análogos & derivados , Infecções por Acinetobacter/mortalidade , Acinetobacter baumannii/efeitos dos fármacos , Adulto , Bacteriemia/mortalidade , Carbapenêmicos/farmacologia , Estudos de Coortes , Colistina/farmacologia , Estado Terminal , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minociclina/administração & dosagem , Minociclina/farmacologia , Pontuação de Propensão , Análise de Sobrevida , Tigeciclina , Resultado do Tratamento
4.
Zoonoses Public Health ; 65(5): 584-588, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29659194

RESUMO

Diagnosis of acute hepatitis E virus (HEV) infection is established by detection of anti-HEV IgM antibodies by ELISA or by amplification of serum viral RNA. Here, we evaluate the diagnostic value of testing HEV RNA in saliva to identify patients with acute HEV infection. Prospective proof-of-concept study including patients with acute hepatitis. Whole blood and neat saliva samples were obtained from all patients. Saliva samples were processed and analysed for HEV RNA by RT-PCR within 2 hr after collection. A total of 34 patients with acute hepatitis and 12 healthy donors were included in the study. HEV RNA in serum was confirmed by RT-PCR in eight of these patients (23.5%; 95% CI: 12.2%-40.2%). HEV was isolated in the saliva of eight of 34 patients (23.5%; 95% CI: 12.2%-40.2%). All patients with HEV RNA amplified in saliva had detectable HEV RNA in serum. HEV was isolated neither in the saliva of any of the 26 patients without detectable HEV RNA in serum nor in healthy donors. Our study suggests that acute HEV infection could be diagnosed by assessing viral load in saliva.


Assuntos
Vírus da Hepatite E , Hepatite E/diagnóstico , RNA Viral/isolamento & purificação , Saliva/virologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/sangue , RNA Viral/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Testes Sorológicos , Adulto Jovem
5.
Mol Endocrinol ; 9(1): 96-107, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7760854

RESUMO

Transcription of both Xenopus thyroid hormone receptor (TR) genes, xTR alpha and -beta, is strongly up-regulated by their own ligand T3 during natural or T3-induced metamorphosis of tadpoles and in some Xenopus cell lines. To explain this autoinduction, we analyzed the sequence of 1.6 kilobases of xTR beta promoter for putative T3-responsive elements. Two direct repeat +4 AGGTCA hexamer motifs (DR+4), an imperfect distal (-793/-778) and a perfect proximal (-5/11) site, a DR+1 site, and some possible half-sites were located in the 1.6-kilobase promoter. Transfection of Xenopus XTC-2 cells (which express xTR alpha and -beta) and XL-2 cells (which predominantly express TR alpha) with chloramphenicol acetyltransferase reporter constructs of deletion mutants and promoter fragments showed that the distal and proximal DR+4 sites responded to T3, although other flanking sequences may also play a role. The thyroid hormone-responsive element half-site present as DR+1 in the up-stream sequence at -1260/-950, when cloned in front of a heterologous promoter, functions independently. T3 enhanced transcription from the two DR+4-containing fragments when present together by only 2- to 3-fold due to a high basal activity. Overexpression of unliganded xTR alpha and xTR beta in XTC-2 cells repressed basal activity, which was then enhanced 7- to 4-fold by T3, respectively; with XL-2 cells cotransfected with xTR beta, T3 inducibility increased to 16-fold. Electrophoretic mobility shift assays with recombinant Xenopus TR alpha, TR beta, retinoid-X receptor-alpha (RXR alpha) and RXR gamma proteins showed that TR-RXR heterodimers, but not TR or RXR monomers or homodimers, strongly bound the natural and synthetic distal and proximal DR+4 elements in a ligand-independent manner. TR/RXR heterodimers exhibited the highest binding affinity for a 28-mer oligonucleotide probe for the -5/11 proximal DR+4 site, with only slight binding to DR+1 (retinoid-X-responsive element-like) site. The xTR beta promoter binding to XTC-2 cell nuclear extract suggested the in vivo relevance of the findings with recombinant TR/RXR heterodimers. It is concluded that xTR alpha and -beta proteins are capable of regulating the expression of xTR beta gene, which can explain its autoinduction seen during T3-induced metamorphosis.


Assuntos
Autorreceptores/genética , Regulação da Expressão Gênica , Genes , Receptores dos Hormônios Tireóideos/genética , Tri-Iodotironina/farmacologia , Xenopus laevis/genética , Animais , Autorreceptores/biossíntese , Sequência de Bases , Núcleo Celular/química , Regulação da Expressão Gênica/efeitos dos fármacos , Larva , Metamorfose Biológica , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Receptores do Ácido Retinoico/metabolismo , Receptores dos Hormônios Tireóideos/biossíntese , Proteínas Recombinantes de Fusão/farmacologia , Receptor alfa de Ácido Retinoico , Deleção de Sequência , Transcrição Gênica , Transfecção , Xenopus laevis/crescimento & desenvolvimento
6.
Mol Cell Endocrinol ; 87(1-3): 105-13, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1446782

RESUMO

To determine if the autoinduction of thyroid hormone receptor (TR) alpha and beta mRNAs during metamorphosis in Xenopus tadpoles can be reproduced in cultured cells, we have screened four Xenopus cell lines (XTC-2, XL-177, XL2 and Kr) for receptor transcripts and their response to thyroid hormone. Exposure of XTC-2 cells to 10(-9) M triiodothyronine (T3) for 24 h upregulated TR alpha and beta mRNAs by 2-4- and 10-40-fold, respectively. In view of the marked similarity of the differential distribution of the two transcripts and their upregulation by T3 to the pattern of autoinduction seen in whole tadpoles, the process was studied in greater detail in XTC-2 cells. The time-course of autoinduction of TR alpha and beta mRNAs in these cells also resembled that in vivo, the two transcripts being significantly induced by 3-6 h after T3. Dose-response to T3, and the relative responses to its active and inactive analogs, confirmed that the process of autoinduction was initiated by thyroid hormone receptor with the same functional characteristics as that found in all amphibian and mammalian tissues. Experiments performed with cycloheximide suggested that intermediary protein(s) were involved in autoinduction, so that TR genes cannot be considered as 'immediate early' genes for this process. The possible advantages of studying thyroid hormone action in metamorphosis in XTC-2 cells are briefly discussed.


Assuntos
Metamorfose Biológica/genética , Receptores dos Hormônios Tireóideos/biossíntese , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia , Xenopus/crescimento & desenvolvimento , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , RNA Mensageiro/biossíntese , Receptores dos Hormônios Tireóideos/genética , Tiroxina/análogos & derivados , Tri-Iodotironina/análogos & derivados , Regulação para Cima/efeitos dos fármacos
7.
J Steroid Biochem Mol Biol ; 46(2): 105-19, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8664159

RESUMO

Although downregulation of receptors by their respective hormonal ligands is a well-studied phenomenon, relatively less is known about autoupregulation of receptors. However, an increasing number of observations of the latter process are now being reported. Here, we discuss the phenomenon of autoinduction of nuclear receptors of the steroid/thyroid hormone gene family, and its significance in the context of the developmental and gene regulatory function of the ligands. Much of this review is illustrated by recent work from our laboratory on the autoregulation of Xenopus estrogen (ER) and thyroid hormone (TR) receptors and their transcripts, accompanying or anticipating vitellogenesis and metamorphosis, respectively. The activation by estrogen (E2) of the silent vitellogenin genes and the induction of FOSP-1 genes in primary cultures of hepatocytes from male Xenopus and oviduct cells, respectively, are tightly coupled to a substantial upregulation of ER protein and its transcript. The developmental competence to activate vitellogenin in response to E2 was found to be acquired during late metamorphosis. Since the latter process is obligatorily controlled by thyroid hormones (TH), we extended our studies to the developmental and hormonal regulation of Xenopus TR genes. Although very low levels of TR alpha and beta mRNAs are detectable in embryos and early larvae, there is a large increase in the accumulation of both transcripts before the onset of metamorphosis (stage 54 tadpoles), by which time the larval thyroid gland has first begun to secrete TH. Filter and in situ hybridization revealed that the two transcripts were differentially regulated and were not equally distributed in all regions or tissues of the tadpole. Their concentration peaks at metamorphic climax and drops to low levels in froglets and adult Xenopus. Exogenous TH given to pre-metamorphic tadpoles is known to induce metamorphosis precociously. Administration of triiodothyronine (T3) to early tadpoles (stages 50/52) caused a rapid upregulation of TR alpha and beta mRNAs which was particularly marked for the beta transcript (20- to 50-fold increase in steady-state levels). This autoinduction, which is the earliest response to T3, is mimicked to variable degrees in some Xenopus cell lines. In XTC-2 cells, in which the in vivo process is fully reproduced, it was possible to show with cycloheximide that the increase in TR mRNA requires protein synthesis. It was also possible to show by transfection of XTC-2 cells with a reporter-promoter construct of Xenopus albumin gene, which is a target for T3, that the extra TR mRNA increases functional receptor in the cell. Although the role of TH is well-known in metamorphosis, we found that TR is also autoinduced in primary culture of adult male Xenopus hepatocytes. The significance of this finding lies in the fact that T3 potentiates the autoinduction of ER and the de novo activation of vitellogenin genes by E2. Prolactin (PRL) is known to exert a "juvenilizing" action by preventing the induction of amphibian metamorphosis by TH. It is therefore highly significant that PRL prevented both the autoinduction of TR alpha and beta mRNAs in whole tadpoles and organ cultures and the activation of TR target genes, such as those encoding albumin and 63 kDa adult-type keratin. Although how PRL exerts its antimetamorphic effect is not known, these findings lead us to propose a dual threshold model for the autoinduction of TR, whereby the autoinduction of TR genes requires a very low level of TR and TH to rapidly augment the amount of functional TR. This higher amount of receptor would be required to achieve a higher threshold to activate "downstream" or target genes which specify the adult phenotype at the end of metamorphosis. Finally, a survey of recent literature shows that the phenomenon of autoinduction is not restricted to Xenopus ER and TR but is more widespread among members of the nuclear receptor family.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Receptores de Estrogênio/genética , Receptores dos Hormônios Tireóideos/genética , Animais , Técnicas de Cultura , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Metamorfose Biológica , Prolactina/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Xenopus/embriologia
8.
Clin Chim Acta ; 224(2): 119-23, 1994 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-8004781

RESUMO

Analytical goals for rectilinearity based on within-subject biological variation have not yet been advocated. On the other hand, the statistical tests to evaluate rectilinearity may be too restrictive for clinical purposes. If rectilinearity of the least-squares regression is rejected by the statistical test used, we propose to compare the systematic error introduced using such a regression line as the calibration function, with the allowable total error. Since total error ideally should be less than the within-subject biological coefficient of variation (C.V.Bw) the goal for rectilinearity we propose is that the maximum allowable systematic relative error produced by the calibration function (LoRi) when a lack of rectilinearity really occurs is: LoRi < C.V.Bw -1.96 C.V.M, where C.V.M is the between-run metrological coefficient of variation of the measurement procedure, corresponding to the value of concentration under study.


Assuntos
Calibragem/normas , Química Clínica/normas , Algoritmos , Química Clínica/estatística & dados numéricos , Humanos , Análise dos Mínimos Quadrados , Análise de Regressão
9.
Med Clin (Barc) ; 107(3): 90-2, 1996 Jun 15.
Artigo em Espanhol | MEDLINE | ID: mdl-8754494

RESUMO

BACKGROUND: We studied pS2 protein in breast tumors and its relation with estrogen and progesterone receptors and with anatomopathological characteristics of the tumors. MATERIAL AND METHODS: We measured the pS2 content (by IRMA) and steroid receptors content (by EIA) in 151 breast tumors. Results were compared and correlated with tumoral characteristics. RESULTS: 53% of tumors were pS2+. Among them, 91% were estrogen receptors +.86% of estrogen receptors negative tumors were pS2-. We observed correlation between pS2 and estrogen receptors values (r = 0.56; p < 0.0001) and between pS2 and progesterone receptors values (r = 0.53; p < 0.0001). Distributing the tumors in pS2+ and pS2-, we observed association between pS2+ and estrogen receptors + (chi 2 = 45.6; p < 0.0001) and pS2+ and progesterone receptors + (chi 2 = 43.1; p < 0.0001). However, we found a 18.5% of estrogen receptors + pS2- tumors. We observed a significant difference between GII and GIII tumoral grades (chi 2 = 5.51; p < 0.019), with a majority of pS2+ tumors in GII and pS2- tumors in GIII. CONCLUSIONS: The estrogen receptors in estrogen receptors + ps2- tumors may be non functional. The presence of pS2 protein alternative to that of progesterone receptors may indicate a functional heterogeneity of the estrogen receptors system, which is of interest in evaluating prognosis and response to the hormonal therapy.


Assuntos
Neoplasias da Mama/metabolismo , Estrogênios/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Proteínas , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Fator Trefoil-1 , Proteínas Supressoras de Tumor
10.
Med Clin (Barc) ; 102(5): 169-71, 1994 Feb 12.
Artigo em Espanhol | MEDLINE | ID: mdl-8127165

RESUMO

BACKGROUND: The usefulness of the concentration of salivary 17-hydroxyprogesterone (17-OHPRG) in the diagnosis of congenital adrenal hyperplasia by partial deficiency of 21-hydroxylase was studied. As a biologic medium, saliva has important advantages such as facility in sample collection and the avoidance of the stress of venous puncture. METHODS: Salivary 17-OHPRG was measured by a direct solid phase radioimmunoassay. A control group made up of 28 males and 26 females was studied. The group of patients included 30 women, 10 of them with a previous diagnosis of partial deficit of 21-hydroxylase. Basal values were established in the control group and were compared with those found in the patients in whom a stimulation test with adrenocorticotropin (ACTH) was performed collecting blood and saliva samples. RESULTS: The levels of 17-OHPRG observed in the patients with partial deficiency of 21-hydroxylase were significantly higher than those found in the control group and in the group with hirsutism, including both basal levels and those following stimulation. The correlation between the values found in blood and saliva was very significant. CONCLUSIONS: The measure of 17-hydroxyprogesterone in saliva by a method of direct radioimmunoassay is a valid alternative test to serum measure in both basal conditions and following a stimulation test.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Hirsutismo/metabolismo , Hidroxiprogesteronas/análise , Saliva/química , 17-alfa-Hidroxiprogesterona , Hiperplasia Suprarrenal Congênita/metabolismo , Adulto , Feminino , Humanos , Masculino , Radioimunoensaio
12.
Virology ; 150(1): 117-25, 1986 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-3006331

RESUMO

We have prepared and analyzed 40 HSV-1 intratypic recombinants with regard to plaque morphology and glycoprotein C(gC) phenotypes. Vero cells have been cotransfected with the intact genome of HSV-1(F) and cloned or uncloned DNA fragments from HSV-1(MP) and recombinants inducing the fusion of Vero cells [syncytial (Syn) recombinants] have been selected and purified. Marker transfer of the Syn phenotype has been observed with the cloned BamHI L and B fragments (0.706-0.745 and 0.745-0.810 map units, respectively) as well as with the uncloned HpaI TXO fragment (0.710-0.761) from MP DNA. No marker transfer has been observed with F DNA alone or with the cloned BamHI N fragment (0.863-0.898 map units). When viruses expressing the Syn phenotype in Vero cells were tested in HEp-2 cells, three kinds of recombinants were observed. Members of the first class expressed a wild type, cytoaggregating (Syn+), plaque morphology in these cells. Members of the second class induced the complete fusion (Syn phenotype) of the cells. Members of the third class induced an intermediate plaque morphology, characterized by the formation of groups of polykaryocytes (fused cells) but without formation of a complete syncytium. All recombinants expressing the Syn+ phenotype in HEp-2 cells were also gC+, whereas recombinants expressing the Syn phenotype in these cells were gC- with one exception, in which low levels of gC could be detected (but clearly less than with HSV-1(F]. Concerning polykaryocytic class of recombinants, some of them were gC+ while others expressed only low amounts of gC; no gC- virus was observed within this class of recombinants. The three classes of recombinants were observed with each of the cloned BamHI L and B fragments and also with the HpaI TXO fragment, suggesting the existence of multiple adjacent or overlapping loci affecting plaque morphology and the control of the accumulation or the synthesis of gC at both sides of 0.745 map units.


Assuntos
Simplexvirus/genética , Proteínas do Envelope Viral/genética , Proteínas Virais/genética , Animais , Linhagem Celular , Mapeamento Cromossômico , DNA Viral/genética , Genes Reguladores , Genes Virais , Humanos , Fenótipo , Recombinação Genética , Proteínas Virais de Fusão , Ensaio de Placa Viral
13.
Exp Cell Res ; 250(2): 364-75, 1999 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10413590

RESUMO

Osteoclasts are postmitotic, multinucleated giant cells generated by the fusion of hematopoietic mononuclear precursors from the monocyte-macrophage lineage. In culture, adherent macrophages from blood-derived monocytes grow, gather, and fuse together to form multinucleated osteoclast-like cells. These events are controlled by 1,25(OH)(2)D(3). To sort out new 1,25(OH)(2)D(3) target genes involved in osteoclast differentiation, we have performed an RT-PCR differential display using mRNA from macrophages induced for 10 h by 1,25(OH)(2)D(3) compared to nontreated cells. We have identified a new target gene, a chick ATP-dependent Ca(2+) pump, ChkSERCA3. Although the level of the corresponding transcript increases during the differentiation process from macrophages to osteoclast-like cells, its steady-state level is downregulated by hormone treatment. The action of 1,25(OH)(2)D(3) on the Ca(2+)-ATPase gene expression is independent of de novo protein synthesis and is hormone dose dependent. This expression in adult chick was restricted to the hematopoietic cell lineage, spleen, lung, intestine, and brain, whereas no expression was detected in embryos. The function of the protein can be predicted from its high homology with the other members of the SR ATP-dependent Ca(2+) pump family, i.e., storage and control of cytosolic Ca(2+) directly regulated by 1, 25(OH)(2)D(3), further supporting the critical role for intracellular calcium in highly specialized cells such as osteoclasts.


Assuntos
Calcitriol/farmacologia , ATPases Transportadoras de Cálcio/genética , Galinhas/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Monócitos/metabolismo , Retículo Sarcoplasmático/enzimologia , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Clonagem Molecular , Células Gigantes/citologia , Células Gigantes/efeitos dos fármacos , Células Gigantes/metabolismo , Humanos , Isoenzimas/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Dados de Sequência Molecular , Monócitos/citologia , Monócitos/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Filogenia , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Retículo Sarcoplasmático/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
14.
J Biol Chem ; 273(17): 10638-46, 1998 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9553126

RESUMO

The carbonic anhydrase II gene, whose transcription is enhanced by 1, 25-dihydroxyvitamin D3 (1,25-(OH)2D3), encodes an important enzyme in bone-resorbing cells derived from the fusion of monocytic progenitors. We analyzed the 1,25-(OH)2D3-mediated activation of the avian gene by transient transfection assays with promoter/reporter constructs into HD11 chicken macrophages and by DNA mobility shift assays. Deletion and mobility shift analyses indicated that the -62/-29 region confers 1,25-(OH)2D3 responsiveness and forms DNA-protein complexes. The addition of an anti-vitamin D receptor (VDR) antibody inhibited binding to this sequence, whereas anti-retinoid X receptor (RXR) antibody generated a lower mobility complex. Therefore, we concluded that this element binds a VDR.RXR heterodimer, but the addition of extra 1,25-(OH)2D3 had no effect on the formation of this complex. Moreover, the use of nuclear extracts from 1,25-(OH)2D3-treated macrophages led to the formation of an additional high mobility complex also composed of VDR.RXR heterodimer. Mutations provided evidence that the 1, 25-(OH)2D3-mediated activation of the carbonic anhydrase II gene is mediated by VDR.RXR heterodimers bound to a DR3-type vitamin D response element with sequence AGGGCAtggAGTTCG. This vitamin D response element is also functional in the ROS 17/2.8 osteoblasts.


Assuntos
Anidrases Carbônicas/genética , Regiões Promotoras Genéticas , Proteína de Ligação a Vitamina D/química , Animais , Sequência de Bases , Núcleo Celular/metabolismo , Galinhas , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Dimerização , Mutagênese , Ratos , Sequências Reguladoras de Ácido Nucleico , Células Tumorais Cultivadas , Proteína de Ligação a Vitamina D/metabolismo
15.
J Gen Virol ; 68 ( Pt 9): 2455-9, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2821182

RESUMO

We have tested a number of herpes simplex virus type 1 (HSV-1) populations for their ability to enter and express virus polypeptides in non-permissive rat XC cells. The viruses tested included 40 intratypic F(MP) recombinants and different batches of virus, belonging to the same strains, that had been produced in two different permissive systems (HEp-2 or Vero cells). Our results indicated that the ability to infect XC cells was determined in part by genetic elements of the virus genome and in part by phenotypic characteristics conferred by the permissive cell that had produced the virus: a virus strain like HSV-1 MP which, when produced in HEp-2 cells, was able to infect XC cells, lost this ability when produced in Vero cells. Working only with viruses produced in HEp-2 cells we showed that the ability to enter XC cells could be transferred from the MP strain to the F strain (which does not normally infect XC cells efficiently) by transfer of the cloned BamHI B (map units 0.745 to 0.81) or BamHI L (map units 0.706 to 0.745) fragments isolated from MP DNA. The implicated locus or loci seemed to segregate, however, from loci controlling gC synthesis and cell fusion, which have been described as mapping in the same region.


Assuntos
Transformação Celular Viral , Simplexvirus/fisiologia , Animais , Linhagem Celular , Humanos , Ratos , Simplexvirus/genética , Especificidade da Espécie , Células Vero
16.
J Gen Virol ; 65 ( Pt 8): 1331-40, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6086819

RESUMO

The expression of immediate-early (IE) genes of herpes simplex virus type 1 (HSV-1, MP strain) in non-permissive rat XC cells was analysed and compared with the expression of IE genes in permissive HEp-2 cells by the following three methods: analysis of virus polypeptide synthesis in infected cells, Northern blot hybridization between poly(A) nuclear or cytoplasmic RNA and in vitro labelled virus DNA or plasmid-cloned fragments corresponding to IE genes, and ability of poly(A) cytoplasmic RNAs to direct synthesis of virus polypeptides in vitro. ICP4 (175K), ICP0 (110K) and ICP27 (62K) were synthesized in XC cells although in smaller amounts than in HEp-2 cells; ICP4 is functional since early and late polypeptides could be observed. Their corresponding mRNAs were present at low levels in nuclei and in cytoplasm and are functional since the polypeptides were synthesized in a rabbit reticulocyte system. ICP22 (68K) was not detectable in infected XC cells; its mRNA was present in nuclei and in cytoplasm, but it is not functional since the corresponding polypeptide was not synthesized in a rabbit reticulocyte system. This suggests some structural differences in the ICP22 mRNA molecules in infected XC and HEp-2 cells and implicates cellular determinants in the control of the expression of HSV-1 IE genes.


Assuntos
Herpes Simples/genética , Simplexvirus/genética , Proteínas Virais/genética , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , DNA Viral/genética , Regulação da Expressão Gênica , Genes Virais , Humanos , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Viral/genética , Transcrição Gênica , Replicação Viral
17.
Virology ; 132(2): 315-24, 1984 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-6322415

RESUMO

The ability to induce the synthesis of virus polypeptides in nonpermissive XC cells by several strains, variants, and intratypic recombinants of HSV-1 has been investigated. Our results show that (i) whereas HSV-1 strains mP and MP, and recombinants F(MP)A through D (Ruyechan et al., J. Virol. 29, 677-697, 1979) and HFEMtsB5/MP3 (Manservigi et al., Proc. Nat. Acad. Sci. USA 74, 3913-3917, 1977) induced in XC cells the synthesis of several virus polypeptides (the "positive" viruses), in the case of HSV-1 strain F, variants HFEMtsB5 and mPtsHA1 (both tested at 33 degrees), and recombinants F(MP)E and F(MP)F, no virus specific polypeptides could be detected in these cells (the "negative" viruses). (ii) Failure of the "negative" viruses to synthesize polypeptides in XC cells could be explained by failure of the virions to penetrate the cells since polyethylene glycol, a fusion promotor agent, enabled these viruses to overcome the blockage of their expression. (iii) The ability to modulate penetration into XC cells is genetically determined. A locus affecting this function maps between coordinates 0.70 to 0.82 of HSV-1 DNA and is closely linked to Cr, a locus controlling the synthesis or accumulation of virus glycoprotein C (gC) (Ruyechan et al., 1979). (iv) A decrease in the amount of gC, relative to gB, is associated with an enhanced ability to enter XC cells, suggesting that gC may control penetration into these restrictive cells by negatively modulating the gB promoted fusion between host cell and virion membranes.


Assuntos
Recombinação Genética , Simplexvirus/patogenicidade , Proteínas do Envelope Viral , Proteínas Virais/análise , Animais , Linhagem Celular , Chlorocebus aethiops , Glicoproteínas/biossíntese , Humanos , Polietilenoglicóis/farmacologia , Simplexvirus/genética , Proteínas Virais/biossíntese , Virulência
18.
Clin Chem ; 43(4): 557-61, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9105254

RESUMO

Impaired synthesis of adrenal steroid hormones because of steroid 21-hydroxylase deficiency is one of the most common inborn errors of metabolism. To expedite molecular diagnosis in families with 21-hydroxylase deficiency, we have designed a rapid strategy to determine nine of the most common mutations in the 21-hydroxylase gene. According to the mutation to be detected, we apply either of two simple strategies: digestion with adequate restriction enzyme or use of the amplification-created restriction site (ACRS) approach and subsequent restriction analysis. Both procedures are rapid and, being nonradioactive, are safer to perform; moreover determination of zygosity in the analyzed mutations requires only one tube per mutation.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Análise Mutacional de DNA/métodos , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/enzimologia , Sequência de Bases , Southern Blotting , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Deleção de Genes , Genótipo , Humanos , Reação em Cadeia da Polimerase/métodos
19.
Virology ; 226(2): 393-402, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8955059

RESUMO

Previous work has shown that the 68-kDa immediate-early protein of herpes simplex virus type 1 (HSV-1), also known as ICP22, is involved in the control of viral gene expression, although the precise mechanism remains to be elucidated. In order to study the function(s) of this protein, we constructed expression vectors containing the coding sequence of the ICP22 gene placed under the control of the SV40 or HCMV promoter. After cell transfection, ICP22 synthesis was studied by immunoblotting, using a specific antiserum. In transient expression experiments in COS cells in which the ICP22 vector was under the control of the SV40 promoter, we found that ICP22 was able to inhibit chloramphenicol acetyltransferase (CAT) expression under the control of either the alpha 22 (IE4) promoter or other immediate-early promoters, such as alpha 4 (IE3), alpha 0 (IE1), and alpha 27 (IE2). CAT expression under the control of the alpha 4 (IE3) promoter was inhibited in these cells by expression of ICP22 under the control of the HCMV promoter; it was also inhibited in RAT-1 cells by ICP22 expressed under the control of the SV40 or HCMV promoter. In contrast, CAT expression directed by the SV40 or HCMV promoters was only weakly or not inhibited by the ICP22 vectors. We also constructed an expression vector for UL13, a gene whose product is implicated in the phosphorylation of ICP22. Although CAT expression under the control of the alpha 4 (IE3) promoter was also negatively regulated by the UL13 gene product, the effects of the ICP22 (directed by the SV40 or HCMV promoter) and UL13 vectors were not synergistic; furthermore, at a particular molar ratio of the two vectors, inhibition of CAT activity was partially reversed. The results in the present work suggest that ICP22 can negatively regulate the expression of immediate-early viral genes and that its phosphorylation by UL13 protein kinase might be involved in the modulation of its function.


Assuntos
Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/fisiologia , Proteínas Virais , Sequência de Aminoácidos , Animais , Células COS , Cloranfenicol O-Acetiltransferase/genética , Chlorocebus aethiops , Regulação Enzimológica da Expressão Gênica , Herpesvirus Humano 1/genética , Proteínas Imediatamente Precoces/genética , Dados de Sequência Molecular , Plasmídeos , Regiões Promotoras Genéticas , Proteínas Quinases/genética , Proteínas Recombinantes de Fusão/genética , Células Vero , Proteínas Virais Reguladoras e Acessórias
20.
J Cell Sci ; 111 ( Pt 17): 2563-74, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9701555

RESUMO

Alphavbeta3 is a key integrin mediating adhesion of multinucleated osteoclasts during bone resorption. 1, 25-dihydroxyvitamin D3 upregulates alphavbeta3 integrin expression in mononucleated osteoclast precursors and concomitantly stimulates their differentiation into osteoclasts. This suggests that this integrin could play a major role during osteoclast differentiation. We have developed an in vitro model, in which 1, 25-dihydroxyvitamin D3 sequentially modifies the behavior of macrophages: It first induces rounding up of these cells, then their subsequent aggregation and spreading, which finally leads to cell fusion and the formation of osteoclast-like multinucleated giant cells. We show that, while 1,25-dihydroxyvitamin D3 stimulates the de novo synthesis of alphavbeta3 in macrophages early in this process, its accumulation on the surface is triggered by cell aggregation. A high level of integrin alphavbeta3 cell surface expression correlates with macrophage spreading preceding fusion. This was confirmed by means of novel cell permeable peptides containing the C-terminal sequence of the integrin beta3 tail to specifically block (alphavbeta3 function. Although this peptide has no effect on the aggregation step, it disrupts the spreading of osteoclast precursors and consequently inhibits their fusion. These findings suggest a novel role of the integrin alphavbeta3 in a discrete step of osteoclast differentiation.


Assuntos
Células Gigantes/fisiologia , Osteoclastos/citologia , Receptores de Superfície Celular/biossíntese , Receptores de Vitronectina/biossíntese , Receptores de Vitronectina/fisiologia , Sequência de Aminoácidos , Animais , Calcitriol/farmacologia , Agregação Celular/fisiologia , Diferenciação Celular , Fusão Celular/efeitos dos fármacos , Fusão Celular/fisiologia , Permeabilidade da Membrana Celular , Células Cultivadas , Galinhas , Células Gigantes/metabolismo , Macrófagos , Dados de Sequência Molecular , Monócitos , Osteoclastos/fisiologia , Peptídeos/fisiologia , Receptores de Vitronectina/genética
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