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1.
Plant Dis ; 101(7): 1300-1305, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30682946

RESUMO

Solanum sisymbriifolium, the litchi tomato, is a perennial herbaceous plant from South America that is used as a trap crop to reduce soilborne populations of the pale cyst nematode Globodera pallida, an important potato pathogen. Possible interactions of soilborne potato pathogens Verticillium dahliae and Colletotrichum coccodes with litchi tomato are unknown, yet important for potato production if litchi tomato is to be planted as a trap crop. The goal of this research was to quantitatively assess if litchi tomato is a potential inoculum source for C. coccodes and V. dahliae by comparing colony forming units (CFU) observed in litchi tomato to susceptible and resistant potato cultivars. The potato cvs. Alturas (P = 0.0003), Ranger Russet (P = 0.0193), and Russet Norkotah (P = 0.0022) produced more CFUs of the potato pathotype of V. dahliae than litchi tomato the first of two years of greenhouse trials. Significantly more CFUs of the potato pathotype of V. dahliae were quantified from stems and roots of only cv. Russet Norkotah compared with litchi tomato (P = 0.0001) in the second year. The CFUs for C. coccodes varied between litchi tomato and the potato cvs., perhaps due to varying levels of resistance since litchi tomato is from a selected intermated seed source. Based on these data, the effect of litchi tomato in rotation with potato is likely to have limited effect on the proliferation of V. dahliae or C. coccodes populations in the soil when compared with a susceptible potato cultivar.

2.
Mol Genet Genomics ; 290(1): 329-42, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25248636

RESUMO

The genus Elymus ("Ryegrass") is a repository for a range of species with a variety of haplome contents; hence the pejorative name "dustbin" genus. We have analyzed 1,059 sequences from 128 accessions representing 24 species to investigate the relationships among the StH haplomes-containing species described by Yen and Yang (Genus Elymus Beijing 5:58-362, 2013). Sequences were assigned to "unit classes" of orthologous sequences and subjected to a suite of analyses including BLAST (Basic Local Alignment Search Tool) searches, phylogenetic analysis and population genetic analysis to estimate species diversity. Our results support the genome analyses in Yen and Yang (Genus Elymus Beijing 5:58-362, 2013), i.e., genomic constitution StStHH including variants restricted to Elymus. Population genetic analysis of the 5S nrDNA sequence data revealed that the within-species variance component is roughly ±89 %; thus, we were unable to identify molecular markers capable to separate the 24 species analyzed. Separate phylogenetic analyses of the two unit classes and of all the data exhibit a trend only of the species to cluster on the phylograms. Finally, the analysis provides evidence for the multiple origins of American and Eurasian species.


Assuntos
DNA Ribossômico/genética , Elymus/genética , Variação Genética , Haplótipos/genética , Poliploidia , Sequência de Bases , Teorema de Bayes , Genética Populacional , Modelos Genéticos , Filogenia , Análise de Componente Principal , Especificidade da Espécie
3.
Genome ; 55(3): 177-93, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22338617

RESUMO

Phylogenetic inferences of the polyploid Aegilops taxa were drawn based upon the analysis of 909 nuclear 5S rDNA sequences obtained from 15 Aegilops polyploid taxa (531 sequences new to this paper) and 378 sequences from our previous study on the diploid taxa. The 531 sequences can be split into two orthologous groups (unit classes), the long AE1 and short AE1 previously identified in the diploid set. An examination of the relationships between unit classes and their associated haplomes suggests that U haplome sequences found in Ae. umbellulata are the closest to the T sequences found in Amblyopyrum muticum and that sequences of the polyploid species expected to be the M type found in Ae. comos are more similar to the T haplome sequences, except in the three hexaploids Ae. glumiaristata, Ae. juvenalis, and Ae. vavilovii and the tetraploid Ae. crassa where they are found to be similar to the M haplome sequences. These three hexaploid taxa likely originated from the tetraploid Ae. crassa (DM), while the closest taxon to the fourth hexaploid, Ae. recta, is the tetraploid Ae. neglecta (UM). Based upon the distribution of the unit classes, several reticulate phylogenies depicting evolutionary relationships among diploid, tetraploid, and hexaploid taxa were constructed; however, none of these widely used methods could depict the expected reticulate relationship as previously drawn from cytogenetic analyses in this group of allopolyploid species. These results suggest that evolutionary relationships derived from models based upon the assumption of bifurcating species require careful interpretation when these same models are applied to species with reticulate evolution.


Assuntos
Evolução Biológica , Evolução Molecular , Filogenia , Ploidias , Poaceae/genética , Sequência de Bases , DNA Ribossômico/genética , Haplótipos/genética , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Poaceae/classificação , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
4.
Oncogene ; 30(9): 1046-58, 2011 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-21042283

RESUMO

Tumor growth factor-ß (TGF-ß) signaling in cancer has been implicated in growth suppression of early lesions and enhancing tumor cell invasion and metastasis. However, the cellular mechanisms that determine this signaling output in individual tumors are still largely unknown. In endothelial cells, TGF-ß signaling is modulated by the TGF-ß co-receptor endoglin (CD105). Here we demonstrate that endoglin is expressed in a subset of invasive breast cancers and cell lines and is subject to epigenetic silencing by gene methylation. Endoglin downregulation in non-tumorigenic MCF10A breast cells leads to the formation of abnormal acini in 3D culture, but does not promote cell migration or transformation. In contrast, in the presence of activated ErbB2, endoglin downregulation in MCF10A cells leads to enhanced invasion into a 3D matrix. Consistent with these data, ectopic expression of endoglin in MDA-MB-231 cells blocks TGF-ß-enhanced cell motility and invasion and reduces lung colonization in an in vivo metastasis model. Unlike endothelial cells, endoglin does not modulate Smad-mediated TGF-ß signaling in breast cells but attenuates the cytoskeletal remodeling to impair cell migration and invasion. Importantly, in a large cohort of invasive breast cancers, lack of endoglin expression in the tumor cell compartment correlates with ENG gene methylation and poor clinical outcome.


Assuntos
Antígenos CD/genética , Antígenos CD/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Metilação de DNA/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Endoglina , Feminino , Inativação Gênica , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Reação em Cadeia da Polimerase , Prognóstico , Receptor ErbB-2/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/genética
5.
Plant Dis ; 94(7): 921, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30743575

RESUMO

Virus-like disease symptoms consisting of foliar and veinal necrosis similar to those caused by Coleus vein necrosis virus (CVNV) (2) were observed in plants of coleus (Coleus blume Benth.) 'Rustic Orange' obtained from retail greenhouse outlets in Missouri and Minnesota. Flexuous, filamentous, 750 to 770 nm virus-like particles (vlps) were observed by transmission electron microscopy in negatively stained partially purified leaf tissue extracts from symptomatic 'Rustic Orange' leaf tissue. No other virus-like particles were observed and none were detected in extracts from asymptomatic leaves. These vlps were longer than those of CVNV (640 nm) (2) and were not detected by immunosorbent electron microscopy (ISEM) using antibodies to CVNV (2). Degenerate potyvirus primers PNIbF1 (5'GGBAAYAATAGTGGNCAACC3') and PCPR1 (5'GGGGAGGTGCCGTTCTCDATRCACCA3') (1) and total RNA extracted from 'Rustic Orange' leaf tissue with a Qiagen RNeasy Kit were used for reverse transcription-PCR with Ready-To-Go RT-PCR Beads (GE Healthcare). A 950-bp amplicon was obtained from total RNA from diseased but not from healthy leaf tissue. The nucleotide sequence of the amplicon (GenBank Accession No. GQ268818) had levels of identity to published Tobacco etch virus (TEV) sequences comprising portions of the nuclear inclusion body (NIb) and coat protein (CP) gene regions ranging from 89% (L38714) to 93% (M15239, M11458). The identity of the virus occurring in 'Rustic Orange' was further confirmed by ISEM. Virions were trapped and decorated by antibodies to TEV (ATCC PVAS 32). Systemically infected leaf tissue from Datura stramonium in which the coleus TEV isolate was propagated was used to mechanically inoculate Carborundum-dusted leaves of virus-free test plants of 'Rustic Orange' (Park Seed, Greenwood, SC). Inoculated plants developed foliar necrosis symptoms similar to those observed originally, and the presence of TEV was confirmed by ISEM and RT-PCR and nucleotide sequence analysis as described above. To our knowledge, this is the first report of a disease of coleus caused by TEV. Many of approximately 30 'Rustic Orange' plants in one nursery in Minnesota showed similar necrotic foliar symptoms and randomly selected plants tested positive for TEV by ISEM. This suggests that TEV infection in this variety may be spread by vegetative propagation from infected stock plants. References: (1) Y.-C. Hsu et al. J. Virol. Methods 128:54. 2005. (2) D. S. Mollov et al. Plant Dis. 91:754. 2007.

6.
Horm Behav ; 56(1): 73-83, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19303882

RESUMO

Recent studies suggest that the ability of estradiol to enhance cognitive performance diminishes with age and/or time following loss of ovarian function. We hypothesize that this is due, in part, to a decrease in basal forebrain cholinergic function. This study tested whether donepezil, a cholinesterase inhibitor, could restore estradiol effects on cognitive performance in aged rats that had been ovariectomized as young adults. Rats were ovariectomized at 3 months of age, and then trained on a delayed matching to position (DMP) T-maze task, followed by a configural association (CA) operant condition task, beginning at 12-17 or 22-27 months of age. Three weeks prior to testing, rats started to receive either donepezil or vehicle. After one week, half of each group also began receiving estradiol. Acclimation and testing began seven days later and treatment continued throughout testing. Estradiol alone significantly enhanced DMP acquisition in middle-aged rats, but not in aged rats. Donepezil alone had no effect on DMP acquisition in either age group; however, donepezil treatment restored the ability of estradiol to enhance DMP acquisition in aged rats. This effect was due largely to a reduction in the predisposition to adopt a persistent turn strategy during acquisition. These same treatments did not affect acquisition of the CA task in middle-aged rats, but did have small but significant effects on response time in aged rats. The data are consistent with the idea that estrogen effects on cognitive performance are task specific, and that deficits in basal forebrain cholinergic function are responsible for the loss of estradiol effect on DMP acquisition in aged ovariectomized rats. In addition, the data suggest that enhancing cholinergic function pharmacologically can restore the ability of estradiol to enhance acquisition of the DMP task in very old rats following long periods of hormone deprivation. Whether donepezil has similar restorative effects on other estrogen-sensitive tasks needs to be explored.


Assuntos
Envelhecimento , Inibidores da Colinesterase/administração & dosagem , Cognição/efeitos dos fármacos , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Indanos/administração & dosagem , Piperidinas/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Colina O-Acetiltransferase/metabolismo , Cognição/fisiologia , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Donepezila , Estradiol/sangue , Estrogênios/sangue , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Ovariectomia , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Fatores de Tempo
7.
Gut ; 54(6): 807-13, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15888789

RESUMO

BACKGROUND: Flexible sigmoidoscopy (FS) is a complex technical procedure performed in a variety of settings, by examiners with diverse professional backgrounds, training, and experience. Potential variation in technical quality may have a profound impact on the effectiveness of FS on the early detection and prevention of colorectal cancer. AIM: We propose a set of consensus and evidence based recommendations to assist the development of continuous quality improvement programmes around the delivery of FS for colorectal cancer screening. RECOMMENDATIONS: These recommendations address the intervals between FS examinations, documentation of results, training of endoscopists, decision making around referral for colonoscopy, policies for antibiotic prophylaxis and management of anticoagulation, insertion of the FS endoscope, bowel preparation, complications, the use of non-physicians as FS endoscopists, and FS endoscope reprocessing. For each of these areas, continuous quality improvement targets are recommended, and research questions are proposed.


Assuntos
Neoplasias Colorretais/prevenção & controle , Programas de Rastreamento/métodos , Sigmoidoscopia/normas , Antibioticoprofilaxia/métodos , Anticoagulantes/uso terapêutico , Cirurgia Colorretal/educação , Diagnóstico Precoce , Educação Médica Continuada , Humanos , Consentimento Livre e Esclarecido , Corpo Clínico Hospitalar/educação , Satisfação do Paciente , Encaminhamento e Consulta , Sensibilidade e Especificidade , Sigmoidoscopia/efeitos adversos , Sigmoidoscopia/métodos
8.
Minerva Gastroenterol Dietol ; 50(3): 239-51, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15729199

RESUMO

Endoscopic therapy has emerged as an alternative for patients with symptomatic gastroesophageal reflux disease (GERD) who are seeking a non-pharmacologic, non-surgical intervention. To date, there are 3 basic categories of these endoscopic options: radiofrequency ablation, endoscopic suturing and endoscopic injection. Although the pivotal clinical studies to date have consistently demonstrated efficacy for defined endpoints of symptom control, GERD health related quality of life and discontinuance of acid secretory medications, depending on the therapy, there has been less consistent improvement in objective parameters of pH control and lower esophageal sphincter pressure. Although the data for these procedures has been favorable, extrapolation to justify a more widespread clinical use has been limited by the relative lack of controlled sham studies-although these are currently underway for all of the available therapies. Appropriate patient selection for endoscopic GERD therapy is critical and at present these therapies have the best clinical outcome data in patients who are responsive to therapy with a proton pump inhibitor. The risk/benefit profile, long term durability and cost effectiveness should be considered in all patients being considered when evaluating each of the endoscopic therapies for GERD.


Assuntos
Ablação por Cateter , Esofagoscopia , Refluxo Gastroesofágico/cirurgia , Gastroscopia , Humanos , Projetos de Pesquisa
9.
J Viral Hepat ; 9(6): 411-8, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12431202

RESUMO

Hepatitis B virus (HBV) is responsible for > 350 million cases of chronic hepatitis B worldwide and 1.2 million deaths each year. To explore the use of ribozymes as a novel therapy for HBV infection, nuclease-resistant ribozymes that target highly conserved regions of HBV RNA were screened in cell culture. These synthetic ribozymes have the potential to cleave all four major HBV RNA transcripts and to block the HBV lifecycle by cleavage of the pregenomic RNA. A number of the screened ribozymes demonstrate activity in cell culture systems, as measured by decreased levels of HBV surface antigen, HBV e antigen and HBV DNA. In addition, a lead anti-HBV ribozyme maintains activity against a lamivudine-resistant HBV variant in cell culture. Treatment of HBV transgenic mice with lead anti-HBV ribozymes significantly reduced viraemia compared with saline-treated animals and was as effective as treatment with lamivudine. In conclusion, the therapeutic use of a ribozyme alone or in combination with current therapies (lamivudine or interferons) may lead to improved HBV therapy.


Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , RNA Catalítico/farmacologia , RNA Catalítico/uso terapêutico , Animais , DNA Viral/metabolismo , Endonucleases/farmacologia , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Humanos , Lamivudina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Testes de Sensibilidade Microbiana/métodos , RNA Catalítico/metabolismo , RNA Viral/metabolismo , Células Tumorais Cultivadas
10.
J Neurochem ; 81(6): 1233-41, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12068071

RESUMO

Many phase II protective genes contain a cis -acting enhancer region known as the antioxidant response element (ARE). Increased expression of these genes contributes to the protection of cells from oxidative stress. Transgenic reporter mice were created that carry in their genome the core ARE coupled to the human placental alkaline phosphatase (hPAP) reporter gene. Primary cortical cultures derived from these mice were treated with tBHQ resulting in a dose-dependent increase in hPAP activity. Histochemical staining for hPAP activity was observed in both glia and neurons from tBHQ-treated cultures. The tBHQ-mediated increase in hPAP was not affected by the antioxidant glutathione monoethyl ester (GSHEE), whereas the increase in hPAP following DEM treatment was completely blocked by GSHEE. Pre-treatment of cultures with the PI3-kinase inhibitor LY 294002 demonstrated a dose-dependent decrease in tBHQ-induced hPAP activity. In addition, the tBHQ-mediated expression of ARE-driven genes in primary cortical cultures was blocked by LY 294002. Interestingly, basal expression of Nrf2 was also inhibited by LY 294002. We theorize that increased levels of genes controlled by the ARE are important for cellular protection against oxidative stress. These ARE-hPAP transgenic mice will be an important in vivo model for testing our hypothesis.


Assuntos
Córtex Cerebral/enzimologia , Genes Reporter/fisiologia , Glutationa/análogos & derivados , Neurônios/enzimologia , Oxirredutases/metabolismo , Elementos de Resposta/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Cromonas/farmacologia , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Glutationa/farmacologia , Histocitoquímica , Humanos , Hidroquinonas/farmacologia , Camundongos , Camundongos Transgênicos/genética , Morfolinas/farmacologia , Neurônios/citologia , Placenta/enzimologia , Quinona Redutases/metabolismo , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Am J Ophthalmol ; 132(6): 831-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11730645

RESUMO

PURPOSE: To report the incidence of, and factors associated with, persistent vertical diplopia after cataract surgery. DESIGN: Consecutive interventional case series. METHODS: Retrospectively, all adult patients examined during a five year, five month period because of new onset persistent (>3 months) vertical binocular diplopia after cataract surgery were analyzed. All patients had their cataract surgery at the same outpatient ophthalmic surgery center, and were referred to the author, enabling calculation of incidence. Trends in anesthesia type and strabismus complications therefrom were also assessed. Comparison was made between ophthalmologist-administered retrobulbar anesthesia versus anesthesia staff-administered retrobulbar anesthesia. Incidence during a period in which hyaluronidase was not incorporated in the retrobulbar anesthetic was calculated. RESULTS: Persistent vertical diplopia occurred after cataract surgery in 32 (0.18%) of 17,531 eyes that had cataract surgery. No patient whose cataract surgery was conducted with topical anesthesia (3817 eyes) had persistent vertical diplopia, whereas 32 (0.23%) of the 13714 eyes whose cataract surgery was done after retrobulbar anesthesia were affected. No cases of persistent postoperative diplopia were found among 7410 cataract surgery eyes after retrobulbar injection given by one cataract surgeon. There was a threefold greater number of left eyes involved than right eyes (P <.005). No significant (P >.20) increase in cases of persistent vertical diplopia was noted during a period of hyaluronidase shortage. CONCLUSIONS: In this study, persistent binocular vertical diplopia after cataract surgery occurred in 0.23% of cases in which retrobulbar anesthesia was performed. No cases were found after topical anesthesia. Occurrence may be technique-related.


Assuntos
Extração de Catarata/efeitos adversos , Diplopia/etiologia , Visão Binocular , Idoso , Anestesia Local/efeitos adversos , Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Diplopia/diagnóstico , Traumatismos Oculares/etiologia , Feminino , Humanos , Incidência , Masculino , Ferimentos Penetrantes Produzidos por Agulha/etiologia , Músculos Oculomotores/lesões , Estudos Retrospectivos , Fatores de Risco , Acuidade Visual
13.
J Neurochem ; 76(6): 1670-8, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11259485

RESUMO

Transcriptional control of target genes by antioxidant/electrophile response elements has been well described in peripheral tissues. Genes that are regulated by this mechanism include the antioxidant enzymes NAD(P)H:quinone oxidoreductase, gamma-glutamyl cystine synthetase and glutathione-S-transferase. Antioxidant/electrophile response elements within a gene's promoter confer induction by low-molecular-weight electrophilic compounds such as tert-butylhydroquinone and dimethyl fumarate. We have now examined the ability of antioxidant/electrophile response elements to elicit gene expression in neurons and astrocytes in both brain slices and primary cultures using transient transfection of promoter reporter constructs. Our results using a heat-stable human placental alkaline phosphatase reporter indicate that antioxidant/electrophile response element mediated gene expression is largely restricted to astrocyte cell populations. Placental alkaline phosphatase expression was significantly elevated in astrocytes treated with the antioxidant/electrophile response element inducer dimethyl fumarate. Mutant constructs lacking a functional antioxidant/electrophile response element abolished all placental alkaline phosphatase expression in astrocytes. We suggest that astrocytic metabolic processes that normally aid and/or protect neurons may be controlled via this inducible system.


Assuntos
Antioxidantes/farmacologia , Astrócitos/fisiologia , Córtex Cerebral/fisiologia , Regulação Enzimológica da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutationa Transferase/genética , Regiões Promotoras Genéticas , Quinona Redutases/genética , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Sequência de Bases , Biolística , Células Cultivadas , Córtex Cerebral/citologia , Fumarato de Dimetilo , Fumaratos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Glioma , Humanos , Hibridomas , Hidroquinonas/farmacologia , Técnicas In Vitro , Dados de Sequência Molecular , Neuroblastoma , Neuroglia/citologia , Neuroglia/fisiologia , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Transfecção
14.
Am J Gastroenterol ; 96(1): 27-34, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11197282

RESUMO

OBJECTIVE: Esomeprazole, the S-isomer of omeprazole, achieves a significantly greater healing rate and symptom resolution of erosive esophagitis than that achieved by omeprazole. The objective of this study is to assess the efficacy of the new proton pump inhibitor esomeprazole in preventing relapse over a prolonged period in patients with healed erosive esophagitis. METHODS: A total of 318 gastroesophageal reflux patients whose erosive esophagitis was healed in a comparative study of esomeprazole 40 mg, 20 mg, or omeprazole 20 mg, were randomized to maintenance therapy with once daily esomeprazole 40 mg, 20 mg, or 10 mg, or placebo in a U.S., double-blind multicenter trial. RESULTS: After 6 months, healing was maintained (cumulative life table rates) in 93.6% (95% CI 87.4-99.7) of patients treated with esomeprazole 40 mg, 93.2% (95% CI 87.4-99.0) treated with esomeprazole 20 mg, and 57.1% (95% CI 45.2-69) treated with esomeprazole 10 mg; p < 0.001 vs placebo (29.1%; 95% CI 17.7-40.3). Of patients relapsing, mean time to first recurrence of esophagitis increased with dose, from 34 days (placebo) to 78 days (10 mg), 115 days (20 mg), and 163 days (40 mg). Patients treated with esomeprazole had less frequent and less severe heartburn than those treated with placebo. At month 6, more than 70% of patients being treated with esomeprazole remained symptom-free. CONCLUSIONS: Esomeprazole is effective and well tolerated in the maintenance of a healing erosive esophagitis. Esomeprazole 40 mg and 20 mg maintain healing in over 90% of patients while providing effective control of heartburn symptoms.


Assuntos
Inibidores Enzimáticos/administração & dosagem , Esofagite/tratamento farmacológico , Refluxo Gastroesofágico/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Intervalos de Confiança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Inibidores Enzimáticos/efeitos adversos , Esomeprazol , Esofagite/complicações , Esofagite/patologia , Feminino , Seguimentos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Probabilidade , Valores de Referência , Prevenção Secundária , Resultado do Tratamento
15.
Biochemistry ; 39(50): 15626-32, 2000 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11112551

RESUMO

A combination of site-directed labeling and time-resolved fluorescence anisotropy was used to further elucidate the structure and underlying dynamic features of the type I regulatory (R(I)(alpha)) subunit of the cAMP-dependent protein kinase. Specifically, the consequences of cAMP and the catalytic (C)-subunit binding on the backbone flexibility around seven sites of cysteine substitution and fluorescein maleimide labeling (Thr(6)Cys, Leu(66)Cys, Ser(75)Cys, Ser(81)Cys, Ser(99)Cys, Ser(145)Cys, and Ser(373)Cys) in the R(I)(alpha) subunit were assessed. Focusing on the fast rotational correlation time, the results indicate that most of the interdomain segment connecting the dimerization/docking (D/D) and tandem cAMP-binding domains is probably weakly associated with the latter domain. Also, this segment becomes more tightly bound to the C subunit upon holoenzyme formation. The results also suggest that there is a short 'hinge' segment (around Leu(66)Cys) that could allow the structured interdomain/cAMP-binding and D/D domains to pivot about each other. Finally, cAMP binding dramatically reduces the backbone flexibility around only the two sites of cysteine substitution in the cAMP-binding domains, suggesting a selective structural stabilization caused by cAMP and a "tight" coupling of low-nanosecond fluctuations selectively within the tandem cAMP-binding domains.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Catálise , Proteínas Quinases Dependentes de AMP Cíclico/química , Ativação Enzimática , Mutação , Conformação Proteica , Relação Estrutura-Atividade
19.
J Exp Biol ; 203(Pt 3): 459-70, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10637175

RESUMO

The current model of transepithelial ion movements in the gill of freshwater fish incorporates an apically oriented vacuolar H(+)-ATPase (H(+)V-ATPase; proton pump) that is believed to facilitate both acid excretion and Na(+) uptake. To substantiate this model, we have cloned and sequenced a cDNA encoding the B subunit of the rainbow trout (Oncorhynchus mykiss) H(+)V-ATPase. The cloning of the B subunit enabled an examination by northern analysis of its tissue distribution and expression during external hypercapnia. Degenerate oligonucleotide primers to the B subunit of the H(+)V-ATPase were designed and used in a semi-nested polymerase chain reaction (PCR) to amplify an 810 base pair (bp) product from a trout gill/kidney cDNA library. This PCR product was cloned and sequenced and then used to screen the same cDNA library. The assembled 2262 bp cDNA included an open reading frame coding for a deduced protein of 502 amino acid residues. A BLAST search of the GenBank nucleotide database revealed numerous matches to other vertebrate and invertebrate H(+)V-ATPase B subunits. Protein alignment demonstrated that the trout H(+)V-ATPase B subunit is more than 85 % identical and more than 90 % similar to those in other vertebrate species. An initial analysis of H(+)V-ATPase mRNA tissue distribution revealed significant expression in blood. Although a comparison of perfused tissues (blood removed) with non-perfused tissues demonstrated no obvious contribution of the blood to total tissue H(+)-ATPase mRNA levels, all subsequent experiments were performed using perfused tissues. Levels of H(+)V-ATPase mRNA expression were high in the gill, kidney (anterior or posterior), intestine, heart and spleen, but lower in liver and white muscle. Exposure of the fish to 12 h of external hypercapnia (water P(CO2)=7. 5 mmHg; 1 kPa) was associated with a transient increase (at 2 h) in the levels of H(+)V-ATPase B subunit mRNA in gill and kidney; liver mRNA levels were unaffected. These results are consistent with the hypothesis of an apically localised plasma membrane H(+)V-ATPase in the freshwater trout gill and that the expression of this proton pump is increased during periods of acidosis, at least in part because of an increased steady-state level of H(+)V-ATPase mRNA.


Assuntos
ATPases Translocadoras de Prótons/genética , Vacúolos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Clonagem Molecular , Sondas de DNA , Evolução Molecular , Dados de Sequência Molecular , Oncorhynchus mykiss , Especificidade de Órgãos , Reação em Cadeia da Polimerase , ATPases Translocadoras de Prótons/metabolismo , RNA Mensageiro/análise , Alinhamento de Sequência
20.
J Med Chem ; 42(22): 4640-9, 1999 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-10579826

RESUMO

The synthesis of a series of novel analogues of lipid A, the active principle of lipopolysaccharide, is reported. In these compounds, the 1-O-phosphono and (R)-3-hydroxytetradecanoyl moieties of native Salmonella minnesota R595 lipid A have been replaced with hydrogen and the length of the normal fatty acyl residues has been systematically varied. Normal fatty acid chain length in the 3-O-desacyl monophosphoryl lipid A (MLA) series is shown to be a critical determinant of iNOS gene expression in activated mouse macrophages and the induction of proinflammatory cytokines in human peripheral monocytes. Examination of pyrogenicity in rabbits and lethal toxicity in D-galactosamine-treated mice shows that toxic effects in the MLA series can be ameliorated by modifying fatty acid chain length. When used as an adjuvant for tetanus toxoid vaccines, certain MLA derivatives enhance the production of tetanus toxoid-specific antibodies in mice.


Assuntos
Adjuvantes Imunológicos/síntese química , Lipídeo A/análogos & derivados , Lipídeo A/síntese química , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/toxicidade , Animais , Citocinas/metabolismo , Feminino , Febre/induzido quimicamente , Humanos , Imunoglobulina G/biossíntese , Técnicas In Vitro , Dose Letal Mediana , Lipídeo A/química , Lipídeo A/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Camundongos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Coelhos , Salmonella/química , Relação Estrutura-Atividade , Toxoide Tetânico , Vacinação
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