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1.
Radiother Oncol ; 154: 227-234, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32976869

RESUMO

BACKGROUND AND PURPOSE: This phase 1 trial aimed to determine the maximum tolerated dose (MTD; primary objective) of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients. MATERIALS AND METHODS: The study was designed as an open-label dose-escalation study driven by a Tite-CRM design and followed by an expansion cohort. Ralimetinib was administered orally every 12 h, 7 days a week, for 2 cycles of 2 weeks at a dose of 100, 200 or 300 mg/12 h. Patients received ralimetinib added to standard concurrent RT (60 Gy in 30 fractions) with TMZ (75 mg/m2/day) and 6 cycles of adjuvant TMZ (150-200 mg/m2 on days 1-5 every 28 days). RESULTS: The MTD of ralimetinib was 100 mg/12 h with chemoradiotherapy. The three patients treated at 200 mg/12 h presented a dose-limiting toxicity: one patient had a grade 3 face edema, and two patients had a grade 3 rash and grade 3 hepatic cytolysis (66%). Of the 18 enrolled patients, 15 received the MTD of ralimetinib. At the MTD, the grade ≥ 3 adverse events during concomitant chemoradiotherapy were hepatic cytolysis (2/15 patients), dermatitis/rash (1/15), lymphopenia (1/15) and nausea/vomiting (1/15). No interaction of TMZ and ralimetinib when administrated concomitantly has been observed. Inhibition of pMAPKAP-K2 (-54%) was observed in peripheral blood mononuclear cells. CONCLUSION: This phase 1 trial is the first trial to study the combination of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients. The MTD of ralimetinib was 100 mg/12 h. The most frequent dose-limiting toxicities were hepatic cytolysis and rash.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Quimiorradioterapia , Dacarbazina/uso terapêutico , Glioblastoma/tratamento farmacológico , Humanos , Imidazóis , Leucócitos Mononucleares , Piridinas , Temozolomida/uso terapêutico
2.
Water Sci Technol ; 76(1-2): 164-171, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28708621

RESUMO

The performance and removal mechanisms of a hybrid constructed wetland (HCW) followed by a willow planted filter (WPF) were evaluated for the treatment of a leachate contaminated by wood pole preservatives (pentachlorophenol (PCP) and chromated copper arsenate) to reach the storm sewer discharge limits. The HCW aimed to dechlorinate the PCP and polychlorodibenzo-p-dioxins/polychlorodibenzofuran (PCDD/F) and to remove metals by adsorption and precipitation. The HCW was efficient in removing PCP (>98.6%), oil, arsenic (99.4%), chromium (>99.2%), copper (>99.6%%) and iron (29%) to under their discharge limits, but it was unable to reach those of Mn and PCDD/F, with residual concentrations of 0.11 mg Mn/L and 0.32 pg TEQ/L. Iron and manganese could be removed but were subsequently released by the HCW due to low redox conditions. No dechlorination of PCDD/F was observed since its chlorination profile remained the same in the different sections of the HCW. Adsorption was the most probable removal mechanism of PCDD/F. The WPF was able to remove some residual contamination, but it released Mn at a gradually decreasing rate. Total evapotranspiration of the leachate by a larger fertilized WPF and the construction of an underground retention basin are proposed to prevent any discharge of PCDD/F traces in the environment.


Assuntos
Arseniatos/química , Pentaclorofenol/química , Salix/química , Madeira/química , Adsorção , Benzofuranos/química , Cromo/química , Cobre/química , Polímeros/química , Áreas Alagadas
3.
Am J Infect Control ; 45(9): 964-968, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28549882

RESUMO

BACKGROUND: Several Clostridium difficile infection (CDI) surveillance programs do not specify laboratory strategies to use. We investigated the evolution in testing strategies used across Quebec, Canada, and its association with incidence rates. METHODS: Cross-sectional study of 95 hospitals by surveys conducted in 2010 and in 2013-2014. The association between testing strategies and institutional CDI incidence rates was analyzed via multivariate Poisson regressions. RESULTS: The most common assays in 2014 were toxin A/B enzyme immunoassays (EIAs) (61 institutions, 64%), glutamate dehydrogenase (GDH) EIAs (51 institutions, 53.7%), and nucleic acid amplification tests (NAATs) (34 institutions, 35.8%). The most frequent algorithm was a single-step NAAT (20 institutions, 21%). Between 2010 and 2014, 35 institutions (37%) modified their algorithm. Institutions detecting toxigenic C difficile instead of C difficile toxin increased from 14 to 37 (P < .001). Institutions detecting toxigenic C difficile had higher CDI rates (7.9 vs 6.6 per 10,000 patient days; P = .01). Institutions using single-step NAATs, GDH plus toxigenic cultures, and GDH plus cytotoxicity assays had higher CDI rates than those using an EIA-based algorithm (P < .05). CONCLUSIONS: Laboratory detection of CDI has changed since 2010. There is an association between diagnostic algorithms and CDI incidence. Mitigation strategies are warranted.


Assuntos
Clostridioides difficile/isolamento & purificação , Testes Diagnósticos de Rotina/tendências , Enterocolite Pseudomembranosa/diagnóstico , Enterocolite Pseudomembranosa/epidemiologia , Técnicas Imunoenzimáticas/estatística & dados numéricos , Reação em Cadeia da Polimerase/estatística & dados numéricos , Idoso , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/análise , Toxinas Bacterianas/imunologia , Clostridioides difficile/genética , Clostridioides difficile/imunologia , Estudos Transversais , DNA Bacteriano/genética , Enterocolite Pseudomembranosa/microbiologia , Enterocolite Pseudomembranosa/patologia , Enterotoxinas/análise , Enterotoxinas/imunologia , Feminino , Glutamato Desidrogenase/genética , Humanos , Técnicas Imunoenzimáticas/métodos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase/métodos , Quebeque/epidemiologia
5.
J Med Genet ; 54(3): 157-165, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27738187

RESUMO

BACKGROUND: In 1993, Chitayat et al., reported a newborn with hyperphalangism, facial anomalies, and bronchomalacia. We identified three additional families with similar findings. Features include bilateral accessory phalanx resulting in shortened index fingers; hallux valgus; distinctive face; respiratory compromise. OBJECTIVES: To identify the genetic aetiology of Chitayat syndrome and identify a unifying cause for this specific form of hyperphalangism. METHODS: Through ongoing collaboration, we had collected patients with strikingly-similar phenotype. Trio-based exome sequencing was first performed in Patient 2 through Deciphering Developmental Disorders study. Proband-only exome sequencing had previously been independently performed in Patient 4. Following identification of a candidate gene variant in Patient 2, the same variant was subsequently confirmed from exome data in Patient 4. Sanger sequencing was used to validate this variant in Patients 1, 3; confirm paternal inheritance in Patient 5. RESULTS: A recurrent, novel variant NM_006494.2:c.266A>G p.(Tyr89Cys) in ERF was identified in five affected individuals: de novo (patient 1, 2 and 3) and inherited from an affected father (patient 4 and 5). p.Tyr89Cys is an aromatic polar neutral to polar neutral amino acid substitution, at a highly conserved position and lies within the functionally important ETS-domain of the protein. The recurrent ERF c.266A>C p.(Tyr89Cys) variant causes Chitayat syndrome. DISCUSSION: ERF variants have previously been associated with complex craniosynostosis. In contrast, none of the patients with the c.266A>G p.(Tyr89Cys) variant have craniosynostosis. CONCLUSIONS: We report the molecular aetiology of Chitayat syndrome and discuss potential mechanisms for this distinctive phenotype associated with the p.Tyr89Cys substitution in ERF.


Assuntos
Anormalidades Múltiplas/genética , Síndrome de Dandy-Walker/genética , Deficiências do Desenvolvimento/genética , Ossos Faciais/anormalidades , Proteínas Repressoras/genética , Anormalidades Múltiplas/fisiopatologia , Broncomalácia/genética , Broncomalácia/fisiopatologia , Síndrome de Dandy-Walker/fisiopatologia , Deficiências do Desenvolvimento/fisiopatologia , Exoma/genética , Face/fisiopatologia , Ossos Faciais/fisiopatologia , Feminino , Hallux Valgus/genética , Hallux Valgus/fisiopatologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recém-Nascido , Masculino , Fenótipo
7.
J Hosp Infect ; 93(1): 29-34, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26876749

RESUMO

BACKGROUND: Extensively drug-resistant Acinetobacter baumannii (XDR-Ab) is an increasingly important cause of healthcare-associated infection. Uncertainties remain concerning optimal control measures for healthcare-associated outbreaks. AIM: To describe the epidemiology and control of an XDR-Ab outbreak that involved multiple units of a large hospital from March 2012 to January 2014. METHODS: Case-finding included screening of rectum, groin, throat, nose, wounds, iatrogenic portals of entry, and catheterized sites. Antimicrobial susceptibility was evaluated by disc diffusion and E-test. Resistance genes were detected by polymerase chain reaction. Clonality was assessed by pulsed-field gel electrophoresis. Charts of cases were reviewed to identify risk factors for invasive infection. Control measures included isolation and cohorting of cases, hand hygiene reinforcement, environmental decontamination, and source control with daily baths using wipes pre-impregnated with chlorhexidine gluconate. FINDINGS: A single clonal strain of XDR-Ab colonized or infected 29 patients. Five patients died of XDR-Ab bacteraemia. Transmission occurred primarily on two wards. Colonization was detected at all anatomical screening sites; only 57% (16/28) of cases were rectal carriers. Advanced malignancy was a risk factor for bacteraemia (relative risk: 5.8; 95% confidence interval: 1.2-27.0). Transmission ended following implementation of the multimodal control strategy. No additional nosocomial cases occurred during the following 20 months. CONCLUSION: Our study highlights the need to screen multiple anatomic sites to diagnose carriage and identifies risk factors for XDR-Ab bacteraemia. A multimodal intervention that included daily chlorhexidine baths for cases was rapidly followed by the termination of the outbreak. Hospitals should consider similar interventions when managing future XDR-Ab outbreaks.


Assuntos
Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/isolamento & purificação , Banhos/métodos , Clorexidina/administração & dosagem , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Desinfetantes/administração & dosagem , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/prevenção & controle , Acinetobacter baumannii/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Transmissão de Doença Infecciosa/prevenção & controle , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Feminino , Genes Bacterianos , Humanos , Controle de Infecções/métodos , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Reação em Cadeia da Polimerase
8.
J Clin Microbiol ; 53(10): 3380-3, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26224843

RESUMO

Bacteremia due to Cloacibacillus species is poorly described. We present three cases involving either Cloacibacillus evryensis or Cloacibacillus porcorum. The isolates were identified by 16S rRNA gene sequencing and were susceptible to antibiotics commonly used for anaerobic infections. The clinical significance of these organisms as potential emerging pathogens is discussed.


Assuntos
Bacteriemia/diagnóstico , Bacteriemia/patologia , Bactérias/classificação , Bactérias/isolamento & purificação , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Bacteriemia/microbiologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Novo Brunswick , Filogenia , Quebeque , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Epidemiol Infect ; 143(14): 3069-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25687254

RESUMO

Clostridium difficile infection has gained importance in recent years as a result of the rapid spread of epidemic strains, including hypervirulent strains. This study reports the molecular epidemiology of C. difficile obtained from hospitalized patients in Chile. Seven hundred and nineteen isolates of toxigenic C. difficile from 45 hospitals across the country were characterized through toxin profile, pulsed-field gel electrophoresis (PFGE), and sequencing of the tcdC gene. In addition, polymerase chain reaction (PCR) ribotyping and multilocus sequence typing (MLST) were performed on a subset of selected strains. PFGE typing of 719 isolates of C. difficile produced 60 PFGE patterns (subtypes). Subtype 1 was predominant (79% of isolates) and related to the hypervirulent strain (NAP1). Subtype 1 showed 73% relatedness with nine other subtypes, which had a similar tcdC deletion. Subtype 1 corresponded to ribotype 027 and ST1. This report shows the wide dissemination of the hypervirulent strain NAP1/027/ST1 in Chile.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Epidemias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Toxinas Bacterianas/genética , Criança , Pré-Escolar , Chile/epidemiologia , Clostridioides difficile/classificação , Clostridioides difficile/genética , Análise por Conglomerados , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Hospitais , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Ribotipagem , Adulto Jovem
10.
Epidemiol Infect ; 143(7): 1511-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25140694

RESUMO

The objectives of this study were to characterize methicillin-resistant Staphylococcus aureus (MRSA) blood culture isolates and to determine their relative importance in both nosocomial and community-acquired infections. A total of 535 MRSA blood culture isolates were analysed. In vitro susceptibility to 14 agents was determined. The genes nuc, mecA and coding for PVL toxin were identified by PCR. All isolates were characterized by PFGE or spa typing to assess their genomic relationships. Most MRSA isolates were retrieved from nosocomial bloodstream infections (474, 89%) and were of the CMRSA2 genotype. Healthcare-associated (HA)-MRSA bloodstream infections were associated with older age (70-89 years, P = 0·002) and most often secondary to central line infections (P = 0·005). Among MRSA strains associated with community-acquired (CA)-MRSA, 28·8% were isolated in intravenous drug users. CA-MRSA genotypes were more frequently found in young adults (20-39 years, P < 0·0001) with skin/soft tissue as the primary sources of infection (P = 0·006). CMRSA10 genotype was the predominant CA-MRSA strain. All MRSA isolates were susceptible to doxycycline, tigecycline, trimethoprim/sulfamethoxazole and vancomycin. Both the presence of the genes coding for PVL toxin (89·8%) and susceptibility to clindamycin (86·5%) were predictive of CA-MRSA genotypes. Whereas in the USA, HA-MRSA have been replaced by USA300 (CMRSA10) clone as the predominant MRSA strain type in positive blood cultures from hospitalized patients, this phenomenon has not been observed in the province of Quebec.


Assuntos
Bacteriemia/microbiologia , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Meticilina/farmacologia , Epidemiologia Molecular , Infecções Estafilocócicas/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Bacteriemia/epidemiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Quebeque/epidemiologia , Infecções Estafilocócicas/epidemiologia , Adulto Jovem
11.
Prenat Diagn ; 34(2): 163-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24218399

RESUMO

OBJECTIVES: Cornelia de Lange syndrome (CdLS) is characterized by distinct facial features, growth retardation, upper limb reduction defects, hirsutism, and intellectual disability. NIPBL mutations have been identified in approximately 60% of patients with CdLS diagnosed postnatally. Prenatal ultrasound findings include upper limb reduction defects, intrauterine growth restriction, and micrognathia. CdLS has also been associated with decreased PAPP-A and increased nuchal translucency (NT). We reviewed NIPBL sequence analysis results for 12 prenatal samples in our laboratory to determine the frequency of mutations in our cohort. METHODS: This retrospective study analyzed data from all 12 prenatal cases with suspected CdLS, which were received by The University of Chicago Genetic Services Laboratories. Diagnostic NIPBL sequencing was performed for all samples. Clinical information was collected from referring physicians. RESULTS: NIPBL mutations were identified in 9 out of the 12 cases prenatally (75%). Amongst the NIPBL mutation-positive cases with clinical information available, the most common findings were upper limb malformations and micrognathia. Five patients had NT measurements in the first trimester, of which four were noted to be increased. CONCLUSION: We demonstrate that prenatally-detected phenotypes of CdLS, particularly severe micrognathia and bilateral upper limb defects, are associated with an increased frequency of NIPBL mutations.


Assuntos
Síndrome de Cornélia de Lange/genética , Micrognatismo/diagnóstico por imagem , Proteínas/genética , Deformidades Congênitas das Extremidades Superiores/diagnóstico por imagem , Proteínas de Ciclo Celular , Estudos de Coortes , Síndrome de Cornélia de Lange/complicações , Síndrome de Cornélia de Lange/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Micrognatismo/etiologia , Mutação , Medição da Translucência Nucal , Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos , Análise de Sequência de DNA , Ultrassonografia Pré-Natal , Deformidades Congênitas das Extremidades Superiores/etiologia
13.
Can J Cardiol ; 25(11): 641-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19898696

RESUMO

BACKGROUND: Recent improvements in multidetector computed tomography (MDCT) with 64-slice scanners have allowed acquisition of a coronary study in 5 s to 6 s, with good temporal and spatial resolution. Previous studies have reported an underestimation of plaque burden by MDCT. Whether shorter scan times can allow correct assessment of plaque volume requires comparison with intravascular ultrasound (IVUS). METHODS: Patients (n=30) scheduled for coronary angiography also underwent MDCT and IVUS examinations within 96 h. MDCT examination was performed with a 64-slice scanner. Nitroglycerin was administered before all imaging procedures. MDCT, quantitative coronary angiography (QCA) and IVUS analyses were performed by observers blinded to other results. Plaque volumes were determined by MDCT and IVUS in one vessel, and maximum percentage diameter stenosis was identified in each coronary segment by MDCT and QCA. RESULTS: The mean (+ or - SD) plaque volume was determined to be 179.1 + or - 78.9 mm(3) by MDCT and 176.1 + or - 87.9 mm(3) by IVUS. There was a strong positive correlation for plaque volume between MDCT and IVUS (r=0.84, P<0.0001). Percentage diameter stenosis assessed by MDCT and QCA also correlated well (r=0.88 per patient and r=0.87 per vessel, P<0.0001 for both). The maximum percentage diameter stenosis per vessel was 38.1 + or - 30.2% with MDCT and 34.1 + or - 27.6% with QCA. The sensitivity and specificity of MDCT in detecting stenoses above 50% per vessel were 100% and 91.0%, respectively. CONCLUSIONS: Plaque volumes measured by 64-slice MDCT and IVUS correlate well, without systematic underestimation. The sensitivity and specificity of MDCT to detect stenoses greater than 50% by QCA are excellent with the administration of nitroglycerin before imaging.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Imageamento Tridimensional/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Sensibilidade e Especificidade , Índice de Gravidade de Doença
14.
Clin Genet ; 76(6): 511-23, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19863547

RESUMO

To study the instability of FMR1 triplet repeats in the general population, we screened a prospective sample of 24,449 anonymized mother-offspring pairs and analyzed transmissions of intermediate-size (45-54 triplets) and premutation-size (55-200 triplets) alleles. We screened all mothers for alleles > or = 45 triplets by Southern blot and studied transmission of 545 maternal alleles to their offspring using polymerase chain reaction. Out of 21,411 maternal samples with conclusive results, we identified 250 carriers of at least one intermediate-size allele and 39 carrying a premutation-size allele. Out of a subsample of 430 transmissions of normal-size alleles (< 45 triplets), we observed four (< 1%) unstable transmissions. There were 6/90 intermediate-size unstable alleles (7%) and 11/25 unstable premutation-size alleles (44%). Two mothers transmitted a typical full mutation. The incidence of fragile X syndrome was thus 1/12,225 newborns (upper limit of 95% confidence interval: 1/4638 newborns), but larger in males (1/6209) than females (none detected in over 12,000 newborn females). Intermediate-size alleles were more unstable than normal-size alleles (p = 0.0027), but more stable (about sixfold) than premutation-size alleles (p < 0.0001). Unstable premutation-size alleles harbored the major fragile X haplotype (T50-T42-T62), and this haplotype appeared to be a good predictor of instability in premutations (p = 0.02). Incidence and instability are important to determine the feasibility and cost effectiveness of putative FMR1 screening programs. Carriers of FMR1 alleles of 55+ triplets with no family history of the disease may have a significant risk of expansion to a full mutation in a single generation.


Assuntos
Alelos , Proteína do X Frágil da Deficiência Intelectual/genética , Testes Genéticos , Genética Populacional , Instabilidade Genômica/genética , Mães , Triagem Neonatal , Éxons/genética , Feminino , Genoma Humano/genética , Haplótipos/genética , Heterozigoto , Humanos , Recém-Nascido , Padrões de Herança/genética , Estudos Prospectivos , Expansão das Repetições de Trinucleotídeos/genética
15.
Br J Pharmacol ; 152(1): 141-50, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17603550

RESUMO

BACKGROUND AND PURPOSE: ARL 67156, 6-N,N-Diethyl-D-beta-gamma-dibromomethylene adenosine triphosphate, originally named FPL 67156, is the only commercially available inhibitor of ecto-ATPases. Since the first report on this molecule, various ectonucleotidases responsible for the hydrolysis of ATP at the cell surface have been cloned and characterized. In this work, we identified the ectonucleotidases inhibited by ARL 67156. EXPERIMENTAL APPROACH: The effect of ARL 67156 on recombinant NTPDase1, 2, 3 & 8 (mouse and human), NPP1, NPP3 and ecto-5'-nucleotidase (human) have been evaluated. The inhibition of the activity of NTPDases (using the following substrates: ATP, ADP, UTP), NPPs (pnp-TMP, Ap(3)A) and ecto-5'-nucleotidase (AMP) was measured by colorimetric or HPLC assays. KEY RESULTS: ARL 67156 was a weak competitive inhibitor of human NTPDase1, NTPDase3 and NPP1 with K(i) of 11+/-3, 18+/-4 and 12+/-3 microM, respectively. At concentrations used in the literature (50-100 microM), ARL 67156 partially but significantly inhibited the mouse and human forms of these enzymes. NTPDase2, NTPDase8, NPP3 and ecto-5'-nucleotidase activities were less affected. Importantly, ARL 67156 was not hydrolysed by either human NTPDase1, 2, 3, 8, NPP1 or NPP3. CONCLUSIONS AND IMPLICATIONS: In cell environments where NTPDase1, NTPDase3, NPP1 or mouse NTPDase8 are present, ARL 67156 would prolong the effect of endogenously released ATP on P2 receptors. However, it does not block any ectonucleotidases efficiently when high concentrations of substrates are present, such as in biochemical, pharmacological or P2X(7) assays. In addition, ARL 67156 is not an effective inhibitor of NTPDase2, human NTPDase8, NPP3 and ecto-5'-nucleotidase.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Trifosfato de Adenosina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Nucleotidases/antagonistas & inibidores , 5'-Nucleotidase/antagonistas & inibidores , 5'-Nucleotidase/metabolismo , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Antígenos CD/metabolismo , Apirase/antagonistas & inibidores , Apirase/metabolismo , Fosfatos de Dinucleosídeos/metabolismo , Humanos , Hidrólise , Cinética , Camundongos , Nucleotidases/genética , Nucleotidases/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Pirofosfatases/antagonistas & inibidores , Pirofosfatases/metabolismo , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Timidina Monofosfato/análogos & derivados , Timidina Monofosfato/metabolismo , Uridina Trifosfato/metabolismo
16.
Poult Sci ; 86(4): 630-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17369532

RESUMO

Incomplete Freund's adjuvant (IFA) is used as standard adjuvant for the production of specific antibodies. In this study, we evaluated the ability of supplementation of IFA with 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] or C-phosphate-guanosine-oligodeoxynucleotide (CpG-ODN) to enhance the quantity of specific IgY found in the eggs of hyperimmunized laying hens. In this comparative study, the fimbrial adhesin F4 of porcine enterotoxigenic Escherichia coli was used as prototype immunogen. Hens of 3 groups received by i.m. injection 20 microg of purified F4 adhesin emulsified with 1 of the following adjuvants: 0.5 mL of IFA alone (F4-IFA group), 0.5 mL of IFA supplemented with 285.6 ng of 1alpha,25(OH)(2)D(3) (F4-IFA-D(3) group), or 0.5 mL of IFA supplemented with 10 microg of CpG-ODN (F4-IFA-CpG group). Hens of 2 control groups received PBS or purified F4 alone. Immunization was repeated after 2 and 5 or 7 wk. Eggs were collected at 3- to 4-d intervals from preimmunization to d 79, and whole eggs were tested to measure the quantity of anti-F4 IgY by a standardized indirect ELISA. The quantity of specific anti-F4 IgY present in eggs from immunized hens of the F4-IFA group increased from d 13 to 79, corresponding to the end of the experiment. The values for this group at each time were considered as 100%. Results obtained for the other adjuvants were expressed in relation to this reference method. Supplementation of IFA with 1alpha,25(OH)(2)D(3) did not result in any enhancement of the quantity of anti-F4 IgY present in the eggs. On the other hand, supplementation of IFA with CpG-ODN resulted in an enhancement of yield up to 942% of the F4-specific antibody response. Moreover, the use of CpG-ODN is a cost-effective and ethical refinement for the production of specific antibodies, permitting a reduction in the number of immunizations needed. In conclusion, this study provides strong evidence for the use of IFA supplemented with CpG-ODN rather than IFA alone for the production of high levels of specific antibody in laying hens.


Assuntos
Galinhas/imunologia , Adjuvante de Freund/uso terapêutico , Imunoglobulinas/biossíntese , Animais , Análise Custo-Benefício , Ovos/economia , Feminino , Adjuvante de Freund/economia , Oviposição , Quebeque
17.
Purinergic Signal ; 1(2): 193-204, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18404504

RESUMO

Nucleoside triphosphate diphosphohydrolases 1, 2, 3 and 8 (NTPDases 1, 2, 3 and 8) are the dominant ectonucleotidases and thereby expected to play important roles in nucleotide signaling. Distinct biochemical characteristics of individual NTPDases should allow them to regulate P2 receptor activation differentially. Therefore, the biochemical and kinetic properties of these enzymes were compared. NTPDases 1, 2, 3 and 8 efficiently hydrolyzed ATP and UTP with K (m) values in the micromolar range, indicating that they should terminate the effects exerted by these nucleotide agonists at P2X(1-7) and P2Y(2,4,11) receptors. Since NTPDase1 does not allow accumulation of ADP, it should terminate the activation of P2Y(1,12,13) receptors far more efficiently than the other NTPDases. In contrast, NTPDases 2, 3 and 8 are expected to promote the activation of ADP specific receptors, because in the presence of ATP they produce a sustained (NTPDase2) or transient (NTPDases 3 and 8) accumulation of ADP. Interestingly, all plasma membrane NTPDases dephosphorylate UTP with a significant accumulation of UDP, favoring P2Y(6) receptor activation. NTPDases differ in divalent cation and pH dependence, although all are active in the pH range of 7.0-8.5. Various NTPDases may also distinctly affect formation of extracellular adenosine and therefore adenosine receptor-mediated responses, since they generate different amounts of the substrate (AMP) and inhibitor (ADP) of ecto-5'-nucleotidase, the rate limiting enzyme in the production of adenosine. Taken together, these data indicate that plasma membrane NTPDases hydrolyze nucleotides in a distinctive manner and may therefore differentially regulate P2 and adenosine receptor signaling.

18.
Hum Mol Genet ; 11(4): 371-8, 2002 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11854169

RESUMO

We previously reported a 1:259 prevalence of female carriers of FMR1 premutation-size alleles (greater than 54 triplet repeats) in the general population. We now have screened 10 572 independent males from the same population for similar alleles using high-throughput Southern blotting. We identified 13 male carriers of an allele with more than 54 repeats. This corresponds to a prevalence of 1:813 males (95% confidence interval 1:527 to 1:1781). Haplotype analysis of four markers flanking the triplet array revealed that the prevalence of the major fragile X mutation-associated haplotype was increased among FMR1 alleles of 40-54 repeats. Although sequencing of highly unstable premutation alleles from fragile X families revealed only pure CGG tracts, this was not the case for alleles of similar size that were identified in males from the general population. Forty-eight out of forty-nine alleles of 40 or more triplets had one or two AGG interruptions. This observation, combined with the observation of the enrichment of major fragile X syndrome haplotypes in all alleles of this size, is evidence that the loss of an AGG interruption in the triplet repeat array is not necessary for expansion of normal alleles of 29-30 triplets to intermediate size. The loss of AGG interruptions thus appears to be a late event that leads to greatly increased instability and may be related to the haplotype background of specific FMR1 alleles.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Proteínas do Tecido Nervoso/genética , Proteínas de Ligação a RNA , Repetições de Trinucleotídeos/genética , Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil/epidemiologia , Frequência do Gene , Haplótipos , Heterozigoto , Humanos , Masculino , Prevalência , Quebeque/epidemiologia
19.
Bioorg Med Chem Lett ; 11(24): 3161-4, 2001 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-11720865

RESUMO

Peptidomimetic inhibitors of thrombin lacking the important Ser195-carbonyl interaction have been prepared. The binding energy lost after the removal of the activated carbonyl was recaptured through a series of modifications of the P1 residues of the bicyclic lactam inhibitors. Selected substituted compounds displayed useful pharmacological profiles both in vitro and in vivo.


Assuntos
Antitrombinas/farmacologia , Lactamas/farmacologia , Trombina/antagonistas & inibidores , Animais , Antitrombinas/química , Artérias/efeitos dos fármacos , Técnicas In Vitro , Lactamas/química , Ratos
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