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1.
J Invertebr Pathol ; 194: 107804, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35933037

RESUMO

Ascosphaera (Eurotiomycetes: Onygenales) is a diverse genus of fungi that is exclusively found in association with bee nests and comprises both saprophytic and entomopathogenic species. To date, most genomic analyses have been focused on the honeybee pathogen A. apis, and we lack a genomic understanding of how pathogenesis evolved more broadly in the genus. To address this gap we sequenced the genomes of the leaf-cutting bee pathogen A. aggregata as well as three commensal species: A. pollenicola, A. atra and A. acerosa. De novo annotation and comparison of the assembled genomes was carried out, including the previously published genome of A. apis. To identify candidate virulence genes in the pathogenic species, we performed secondary metabolite-oriented analyses and clustering of biosynthetic gene clusters (BGCs). Additionally, we captured single copy orthologs to infer their phylogeny and created codon-aware alignments to determine orthologs under selective pressure in our pathogenic species. Our results show several shared BGCs between A. apis, A. aggregata and A. pollenicola, with antifungal resistance related genes present in the bee pathogens and commensals. Genes involved in metabolism and protein processing exhibit signatures of enrichment and positive selection under a fitted branch-site model. Additional known virulence genes in A. pollenicola, A. acerosa and A. atra are identified, supporting previous hypotheses that these commensals may be opportunistic pathogens. Finally, we discuss the importance of such genes in other fungal pathogens, suggesting a common route to evolution of pathogenicity in Ascosphaera.


Assuntos
Ascomicetos , Onygenales , Animais , Antifúngicos , Ascomicetos/genética , Abelhas , Genômica , Onygenales/genética , Filogenia
3.
Ann Phys Rehabil Med ; 60(3): 164-176, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27017533

RESUMO

INTRODUCTION: Spatial navigation, which involves higher cognitive functions, is frequently implemented in daily activities, and is critical to the participation of human beings in mainstream environments. Virtual reality is an expanding tool, which enables on one hand the assessment of the cognitive functions involved in spatial navigation, and on the other the rehabilitation of patients with spatial navigation difficulties. Topographical disorientation is a frequent deficit among patients suffering from neurological diseases. The use of virtual environments enables the information incorporated into the virtual environment to be manipulated empirically. But the impact of manipulations seems differ according to their nature (quantity, occurrence, and characteristics of the stimuli) and the target population. METHODS: We performed a systematic review of research on virtual spatial navigation covering the period from 2005 to 2015. We focused first on the contribution of virtual spatial navigation for patients with brain injury or schizophrenia, or in the context of ageing and dementia, and then on the impact of visual or auditory stimuli on virtual spatial navigation. RESULTS: On the basis of 6521 abstracts identified in 2 databases (Pubmed and Scopus) with the keywords « navigation ¼ and « virtual ¼, 1103 abstracts were selected by adding the keywords "ageing", "dementia", "brain injury", "stroke", "schizophrenia", "aid", "help", "stimulus" and "cue"; Among these, 63 articles were included in the present qualitative analysis. CONCLUSION: Unlike pencil-and-paper tests, virtual reality is useful to assess large-scale navigation strategies in patients with brain injury or schizophrenia, or in the context of ageing and dementia. Better knowledge about both the impact of the different aids and the cognitive processes involved is essential for the use of aids in neurorehabilitation.


Assuntos
Sinais (Psicologia) , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/fisiopatologia , Navegação Espacial , Realidade Virtual , Estimulação Acústica , Envelhecimento/psicologia , Doença de Alzheimer/psicologia , Lesões Encefálicas/psicologia , Humanos , Doenças do Sistema Nervoso/etiologia , Testes Neuropsicológicos , Estimulação Luminosa , Esquizofrenia/complicações , Percepção Espacial , Acidente Vascular Cerebral/psicologia
4.
Cytokine ; 88: 177-183, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27643980

RESUMO

Overweight and obesity are associated with chronic and subclinical inflammation due to an imbalance of inflammatory mediators. However, the association with gene polymorphism has been rarely studied in children. The aim of this study was to determine if serum concentrations of C-reactive protein (CRP) and interleukin-6 (IL-6) are related to the IL6 rs1800795, IL6 rs2069845 and CRP rs1205 polymorphisms (SNPs) according to body mass index (BMI) in a sample of children and adolescents. A cross-sectional study in 470 students between 7 and 17yearsof age of anthropometric characteristics, high sensitivity-CRP (Hs-CRP) and IL-6 levels and three SNPs genotyped. The prevalence ratio of hs-CRP>3mg/L in obese individuals was 4.15 (CI 2.43-7.06; p=0.01), and it was 1.91 (CI 1.03-3.55; p=0.03) in overweight individuals and 1.74 (CI 1.05-2.88 p=0.03) in females. Individuals with waist circumference (WC) and body fat percentage (BF%) alterations showed elevated levels of hs-CRP (p=4.3×10-5 and p=5.3×10-6). The combination of any two anthropometric measurement increases CRP levels, especially combinations with obesity body mass index (BMI): BMI+WC and BMI+BF%. Among the overweight/obesity group, T allele carriers of CRP rs1205 showed lower levels of hs-CRP (0.5, IQR=0.3-1.8mg/L) than CC homozygotes (1.5, IQR=0.4-3.4mg/L, p=0.018). Additionally, considering subjects with two or three anthropometric alterations for CRP rs1205: rs1205 T allele carriers had lower levels of hs-CRP (0.7, IQR=0.3-2.7mg/L) than CC homozygotes (1.2, IQR=0.5-3.5mg/L, p=0.02). In conclusion, carriers of the rs1205/T allele with higher BMIs had lower levels of hs-CRP. Schoolchildren who were overweight/obese had higher levels of CRP and IL-6, whereas individuals with WC and BF% alterations had higher levels of CRP.


Assuntos
Índice de Massa Corporal , Proteína C-Reativa , Interleucina-6 , Obesidade , Polimorfismo de Nucleotídeo Único , Circunferência da Cintura , Adolescente , Biomarcadores/sangue , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Criança , Feminino , Humanos , Inflamação/sangue , Inflamação/genética , Inflamação/patologia , Interleucina-6/sangue , Interleucina-6/genética , Masculino , Obesidade/sangue , Obesidade/genética , Obesidade/patologia , Fatores Sexuais
5.
J Invertebr Pathol ; 112(1): 41-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23147103

RESUMO

Ascosphaera fungi are highly associated with social and solitary bees, with some species being pathogenic to bees (causing chalkbrood) while others are not, and proper identification within this genus is important. Unfortunately, morphological characterizations can be difficult, and molecular characterizations have only used one genetic region. We evaluated multiple phylogenies of the Ascosphaera using up to six loci: the Internal Transcribed Spacer (ITS) region, 18S rRNA, 28S rRNA, Elongation Factor-1α (EF-1α) the RNA polymerase II largest subunit (RPB1), and the second largest subunit (RPB2). The ITS sequence alone produced an inadequate phylogeny, and the addition of both the 18S and 28S rRNA loci to the ITS sequence produced a phylogeny similar to that based on all six genetic regions. For all phylogenies, Ascosphaera torchioi was in a separate clade that was the most basal, with a strong genetic similarity to Eremascus albus, introducing the possibility of paraphyly within Ascosphaera. Also, based on this new phylogeny, we now suggest that the Apis mellifera (honey bee) pathogens arose within a group of saprophytes, and the Megachile (leafcutting bees) pathogens arose separately.


Assuntos
Onygenales/classificação , Onygenales/genética , Filogenia , Sequência de Bases , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
J Helminthol ; 79(3): 199-206, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16153313

RESUMO

As part of a urinary schistosomiasis control programme on Zanzibar, an aged cross-sectional survey of 305 children from three schools on Unguja was conducted to investigate the relationships between levels of excreted albumin and haemoglobin in urine and Schistosoma haematobium infection status. Diagnosis was determined by standard parasitological methods, dipstick reagents for microhaematuria, visual inspection for macrohaematuria as well as collection of case-history questionnaire data for self-diagnosis. Prevalence of infection as determined by parasitology was 53.9% and approximately, one quarter of the children examined were anaemic (<11 g dl(-1)). A statistically significant negative association of blood haemoglobin levels of boys and S. haematobium infection intensity status was observed (rs=-0.23, P=0.005). Through sensitivity analysis of urine-albumin values it was determined that a concentration of above >40 mg l(-1), as measured with the HemoCue urine-albumin photometer, had sensitivity, specificity, positive and negative predictive values of 0.90, 0.83, 0.86 and 0.89 respectively against 'gold-standard' parasitology. There was a clear association of reported pain upon micturition for children with elevated urine-albumin levels, with an odds ratio of 20 to 1. Levels of excreted blood in urine were quantified with the HemoCue Plasma/Low Hb photometer. However, dipsticks remain the method of choice for urine-haemoglobin of 0.1 g l(-1) and below. Urine parameters over a 24-h period were assessed in a small sub-sample. Reductions in both albumin and haemoglobin excretion were observed in 11 children 54 days after praziquantel treatment. It was concluded that these rapid, high-through-put, portable HemoCue assays could play a role in better describing and monitoring the occurrence, severity and evolution of urinary schistosomiasis disease. The urine-albumin assay has particular promise as a biochemical marker of S. haematobium induced kidney- and upper urinary tract-morbidity.


Assuntos
Albuminúria/diagnóstico , Hemoglobinúria/diagnóstico , Esquistossomose Urinária/urina , Adolescente , Adulto , Albuminúria/complicações , Albuminúria/epidemiologia , Anemia/complicações , Anemia/diagnóstico , Anemia/epidemiologia , Anti-Helmínticos/uso terapêutico , Criança , Estudos Transversais , Feminino , Hematúria/complicações , Hematúria/diagnóstico , Hematúria/epidemiologia , Hemoglobinas/análise , Hemoglobinúria/complicações , Hemoglobinúria/epidemiologia , Humanos , Masculino , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/epidemiologia , Sensibilidade e Especificidade , Tanzânia/epidemiologia
7.
Cyberpsychol Behav ; 8(1): 76-88, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15738695

RESUMO

Social phobia is one of the most frequent mental disorders and is accessible to two forms of scientifically validated treatments: anti-depressant drugs and cognitive behavior therapies (CBT). In this last case, graded exposure to feared social situations is one of the fundamental therapeutic ingredients. Virtual reality technologies are an interesting alternative to the standard exposure in social phobia, especially since studies have shown its usefulness for the fear of public speaking. This paper reports a preliminary study in which a virtual reality therapy (VRT), based on exposure to virtual environments, was used to treat social phobia. The sample consisted of 36 participants diagnosed with social phobia assigned to either VRT or a group-CBT (control condition). The virtual environments used in the treatment recreate four situations dealing with social anxiety: performance, intimacy, scrutiny, and assertiveness. With the help of the therapist, the patient learns adapted cognitions and behaviors in order to reduce anxiety in the corresponding real situations. Both treatments lasted 12 weeks, and sessions were delivered according to a treatment manual. Results showed statistically and clinically significant improvement in both conditions. The effect-sizes comparing the efficacy of VRT to the control traditional group-CBT revealed that the differences between the two treatments are trivial.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Internet/instrumentação , Transtornos Fóbicos/terapia , Interface Usuário-Computador , Adaptação Psicológica , Adulto , Assertividade , Medo , Feminino , Humanos , Masculino
8.
Cyberpsychol Behav ; 6(4): 411-20, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14511454

RESUMO

Social phobia is an anxiety disorder that is accessible to two forms of treatment yielding scientifically validated results: drugs and cognitive-behavioral therapies. Graded exposure to feared social situations is fundamental to obtain an improvement of the anxious symptoms. Traditionally, exposure therapies are done either in vivo or by imagining the situations. In vivo exposure is sometimes difficult to control and many patients have some difficulties in using imagination. Virtual reality (VR) seems to bring significant advantages. It allows exposures to numerous and varied situations. This paper reports the definition of a clinical protocol whose purpose is to assess the efficiency of a VR therapy compared to a CBT and to the absence of treatment for social phobic patients. It explains the illness' diagnosis and its usual treatments. It exposes all the architecture of the study, the assessment tools, the content and unfold of the therapy sessions. It finally reports first results of a clinical trial in a between-group design in 10 patients suffering from social phobia. The virtual environments used in the treatment reproduce four situations that social phobics feel the most threatening: performance, intimacy, scrutiny and assertiveness. With the help of the therapist, the patient learns adapted cognitions and behaviors with the aim of reducing her or his anxiety in the corresponding real situations. The novelty of our work is to address a group of situations that the phobic patient is most likely to experience and to treat patients according to a precise protocol.


Assuntos
Terapia Comportamental/instrumentação , Terapia Comportamental/métodos , Simulação por Computador , Transtornos Fóbicos/terapia , Terapia Assistida por Computador/instrumentação , Interface Usuário-Computador , Adulto , Protocolos Clínicos , Feminino , Humanos , Masculino , Projetos Piloto , Psicometria , Software , Terapia Assistida por Computador/métodos
9.
Cyberpsychol Behav ; 6(4): 433-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14511457

RESUMO

More than 10 years ago, Tart (1990) described virtual reality (VR) as a technological model of consciousness offering intriguing possibilities for developing diagnostic, inductive, psychotherapeutic, and training techniques that can extend and supplement current ones. To exploit and understand this potential is the overall goal of the "Telemedicine and Portable Virtual Environment in Clinical Psychology"--VEPSY UPDATED--a European Community-funded research project (IST-2000-25323, www.cybertherapy.info). Particularly, its specific goal is the development of different PC-based virtual reality modules to be used in clinical assessment and treatment of social phobia, panic disorders, male sexual disorders, obesity, and eating disorders. The paper describes the clinical and technical rationale behind the clinical applications developed by the project. Moreover, the paper focuses its analysis on the possible role of VR in clinical psychology and how it can be used for therapeutic change.


Assuntos
Simulação por Computador , Transtornos Mentais/terapia , Psicologia Clínica , Terapia Assistida por Computador/métodos , Interface Usuário-Computador , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Microcomputadores , Psicoterapia/instrumentação , Psicoterapia/métodos , Telemedicina
10.
Stud Health Technol Inform ; 85: 395-401, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-15458121

RESUMO

The emergence of new shared media, such as the Internet and virtual reality are changing the ways in which people relate, communicate, and live. Health care, and in particular clinical psychology, is one of the areas that could be most dramatically reshaped by these new technologies. To exploit and understand this potential is the overall goal of the "Telemedicine and Portable Virtual Environment in Clinical Psychology"--VEPSY UPDATED--an European Community funded research project (IST-2000-25323, http://www.vepsy.com) whose specific goal is the development of different PC based virtual reality modules to be used in clinical assessment and treatment. In particular the developed modules have been using to address the following pathologies: anxiety disorders; male impotence and premature ejaculation; obesity, bulimia and binge-eating disorders. The chapter details the general technical and clinical characteristics of the developed modules.


Assuntos
Diagnóstico por Computador , Psicologia Clínica , Telemedicina , Terapia Assistida por Computador , Interface Usuário-Computador , Feminino , Humanos , Itália , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Microcomputadores , Apoio à Pesquisa como Assunto , Software
11.
Addict Behav ; 26(4): 573-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11456078

RESUMO

To assess relationships between alcohol consumption and two dimensions of drinking restraint (temptation and restriction), American and German college students were given the Khavari Alcohol Test (KAT) and the Temptation and Restraint Inventory (TRI). As hypothesized, drinking temptation was a positive predictor of students' alcohol consumption in both countries, but there was no main effect for drinking restriction. Also as hypothesized, American students who were high on drinking temptation drank greater (not smaller) quantities of alcohol if they were also high on drinking restriction. Conversely, German students who were high on drinking temptation drank more alcohol if they were also low on drinking restriction. The results point to cross-cultural similarities and differences in relationships between drinking temptation and restriction and actual alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Estudantes/psicologia , Adolescente , Adulto , Feminino , Alemanha , Humanos , Masculino , Inquéritos e Questionários , Estados Unidos , Universidades
12.
J Pers Soc Psychol ; 75(1): 242-55, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9686462

RESUMO

In previous research, presleep suggestions influenced nocturnal dream content. It was hypothesized that suggesting topics associated with participants' current concerns would influence dream content more than suggesting other topics. Ten students spent 4 nights in a sleep laboratory: an adaptation night, a baseline night, and 2 nights under suggestions to dream about a concern-related or other topic. Concern-related suggestions influenced dream content--largely its central imagery--more than did other suggestions, which did not differ from nonsuggestion. Number of transformations within dreams was uncorrelated with dream vividness, contrary to extended activation-synthesis theory. Thus, the concern-related status of suggestions moderates their effectiveness and, inconsistent with extended activation-synthesis theory but consistent with current-concerns and distributed-activation theories, motivational and volitional processes actively influence dream content.


Assuntos
Nível de Alerta , Sonhos , Sugestão , Vigília , Adolescente , Adulto , Feminino , Humanos , Hipnose , Masculino , Motivação , Polissonografia , Estudantes/psicologia
13.
Psychol Rep ; 82(3 Pt 2): 1091-106, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9709515

RESUMO

This investigation examined the motivational structures of 26 patients diagnosed with alcoholism in comparison to 30 demographically similar technical university students. Responding to the Motivational Structure Questionnaire, the clinical group listed 40% fewer goals, responded as if they needed richer incentives to form strong commitments to goal striving, displayed marginally less average commitment to their goals, and, after other variables were partialled out, expressed less ability to influence the course of goal attainment. There were no differences in their scores on over-all subjective probability of success, the time frame for goal attainment, and their relative scores on anticipated positive and negative emotions and ambivalence. The results suggest group differences in the effects of brain-reward mechanisms.


Assuntos
Alcoolismo/psicologia , Motivação , Adulto , Alcoolismo/reabilitação , República Tcheca , Humanos , Masculino , Conformidade Social , Inquéritos e Questionários
14.
Neuroreport ; 6(10): 1437-40, 1995 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-7488743

RESUMO

SH-SY-5Y human neuroblastoma cells were treated with combinations of the kinase inhibitors HA-1004, W-7 and H-7 and calcium ionophore A23187. Microdensitometric analyses revealed that, in the absence of ionophore-mediated calcium influx, PHF-1 levels were reduced by approximately half in cultures treated with HA-1004 or W-7, but were not reduced by H-7. By contrast, the doubling in PHF-1 immunoreactivity that resulted following ionophore treatment was prevented by all three inhibitors. These analyses demonstrate the recruitment of an additional kinase or kinases in tau phosphorylation following calcium influx, and underscore the possibility that de novo hyperactivation of calcium-dependent kinases may be involved in the early events that propagate PHF formation.


Assuntos
Cálcio/metabolismo , Proteínas Quinases/metabolismo , Proteínas tau/metabolismo , Anticorpos Monoclonais/farmacologia , Neoplasias Encefálicas/enzimologia , Calcimicina/farmacologia , Densitometria , Humanos , Imuno-Histoquímica , Ionóforos/farmacologia , Neuroblastoma/enzimologia , Fosforilação , Inibidores de Proteínas Quinases , Células Tumorais Cultivadas
15.
Biochem J ; 295 ( Pt 2): 565-70, 1993 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8240258

RESUMO

The superoxide-generating NADPH oxidase of neutrophils can be activated in a cell-free system consisting of cell membranes, cytosol and an activating detergent (e.g. arachidonate or SDS). It has previously been reported [Aviram and Sharabani (1989) Biochem. Biophys. Res. Commun. 161, 712-719] that a mixture of phosphoinositides (PPIs), as well as the individual inositol lipids, interfere with the activation process. In the present study it is shown that exposure of the cytosol to PPI results in a progressive (t1/2 = 30 s) loss of its oxidase-supporting activity and that Mg2+ ions eliminate this inactivation. Neomycin, previously described as an inhibitor of cell-free activation, counteracted the effect of PPI and vice versa. Fractionation experiments implicated the p67-phox cytosolic component of the oxidase in the association with PPI. PPI blocked activity of recombinant p67-phox also and quenched the fluorescence intensity of its tryptophan residues. It is suggested that PPIs may mediate the interaction of the oxidase with the cytoskeleton and/or with the membrane.


Assuntos
Citosol/enzimologia , NADH NADPH Oxirredutases/metabolismo , Neutrófilos/enzimologia , Fosfatidilinositóis/metabolismo , Fracionamento Celular , Cromatografia por Troca Iônica , Ativação Enzimática , Humanos , Técnicas In Vitro , Cinética , Magnésio/farmacologia , NADH NADPH Oxirredutases/antagonistas & inibidores , NADPH Oxidases , Neomicina/farmacologia , Espectrometria de Fluorescência
16.
Biochem J ; 285 ( Pt 2): 635-9, 1992 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-1637353

RESUMO

Activation of superoxide-producing NADPH oxidase of neutrophils requires the presence of cell membranes, cytosolic components and arachidonate and is markedly enhanced by non-hydrolysable analogues of guanine nucleotides, i.e. guanosine 5'-[gamma-thio]triphosphate and guanosine 5'[beta gamma-imido]triphosphate (p[NH]ppG). Gel filtration and ultrafiltration of the cytosol decreased the basal activity of NADPH oxidase. Activity could be restored by GTP, suggesting participation of the nucleotide in basal activation. Preincubation of neutrophil cytosol with periodate-oxidized p[NH]ppG (ox-p[NH]ppG) followed by gel filtration resulted in a time-dependent enhancement of basal oxidase activity. The presence of GDP or GTP, but not ATP, during the incubation with ox-p[NH]ppG abolished this enhancement. These data are consistent with a stable association of ox-p[NH]ppG with an oxidase-linked cytosolic protein. SDS/PAGE of neutrophil cytosol preincubated with [3H]ox-p[NH]ppG revealed radioactivity in bands migrating as 100, 70, 47, 34 and 22 kDa proteins. Evidence for covalent labelling of the cytosolic protein p47-phox with [3H]ox-p[NH]ppG is presented. Heterogeneity of cytosolic GTP-binding sites and possible participation of protein p47-phox in functional interaction with GTP analogues during cell-free activation are suggested.


Assuntos
Guanosina Trifosfato/metabolismo , NADH NADPH Oxirredutases/metabolismo , Neutrófilos/enzimologia , Western Blotting , Sistema Livre de Células , Cromatografia em Gel , Citosol/enzimologia , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Humanos , NADPH Oxidases , Testes de Precipitina
17.
J Biol Chem ; 267(12): 8628-35, 1992 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-1569107

RESUMO

Rat hepatic microsomal squalene synthetase (EC 2.5.1.21) was induced 25-fold by feeding rats with diet containing the hydroxymethylglutaryl-coenzyme A reductase inhibitor, fluvastatin, and cholestyramine, a bile acid sequestrant. A soluble squalene synthetase protein with an estimated mass of 32-35 kDa, as determined by gel filtration chromatography on Sephacryl S-200 column, was solubilized out of the microsomes by controlled proteolysis with trypsin. Approximately 25% of the activity was recovered in a soluble form. The enzyme was purified to homogeneity utilizing a series of column chromatography purification steps on DEAE-cellulose, hydroxylapatite, and phenyl-Sepharose sequentially. The purified enzyme showed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Initial kinetic analysis indicated an S0.5 values for trans-farnesyl diphosphate of 1.0 microM and for NADPH of 40 microM. The Vmax with respect to trans-farnesyl diphosphate was calculated at 1.2 mumol/min/mg. NADH also serves as substrate for the reaction with S0.5 value of 800 microM. Western blot analysis utilizing rabbit antisera raised against the purified, trypsin-truncated enzyme showed a single band for the isolated solubilized enzyme at 32-33 kDa and a band for the intact microsomal enzyme at about 45-47 kDa.


Assuntos
Farnesil-Difosfato Farnesiltransferase/metabolismo , Microssomos Hepáticos/enzimologia , Animais , Western Blotting , Cromatografia Líquida , Ditiotreitol/metabolismo , Eletroforese em Gel de Poliacrilamida , Farnesil-Difosfato Farnesiltransferase/antagonistas & inibidores , Farnesil-Difosfato Farnesiltransferase/isolamento & purificação , Hidrólise , Cinética , Masculino , Inibidores de Proteases/farmacologia , Ratos , Ratos Endogâmicos , Tripsina/metabolismo
19.
Dtsch Zahnarztl Z ; 46(11): 743-5, 1991 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1817876

RESUMO

The titanium casting system Cyclarc (Morita) was examined for its suitability for the fabrication of dense, fitting restorations. The investment material Titavest CB exhibited no setting expansion. Instead, thermal expansion, highly dependent on the liquid/power ratio and the temperature during preheating, was observed. The castability of unalloyed titanium is fully acceptable for the fabrication of prosthetic restorations. Single crowns showed a high accuracy of fit, if an optimal liquid/power ratio was used for investment.


Assuntos
Coroas , Técnica de Fundição Odontológica , Restauração Dentária Permanente , Titânio
20.
Biochem Biophys Res Commun ; 177(1): 504-10, 1991 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-2043136

RESUMO

Superoxide production by neutrophil NADPH oxidase activated in a cell-free system consisting of plasma membranes, cytosol and arachidonate is enhanced by nonhydrolyzable analogs of GTP and reduced by GDP. To characterize the interaction of guanine nucleotides with the system, dialdehyde analogs of GTP and GDP (oGTP and oGDP) were employed. oGDP or oGTP caused an irreversible and dose dependent inactivation of NADPH oxidase-supporting cytosolic activity. Cytosol was fractionated on S and Q Sepharose ion exchange columns into three fractions, combinations of which synergistically supported activation of NADPH oxidase. Two fractions shown by immunoblotting to contain the oxidase-linked p47 and p67 proteins were inactivated by oGDP. Labeling with [alpha-32P]-oGTP lead to incorporation of the label into several proteins.


Assuntos
Guanosina Difosfato/análogos & derivados , NADH NADPH Oxirredutases/sangue , Neutrófilos/enzimologia , Cromatografia por Troca Iônica , Citosol/enzimologia , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Difosfato/farmacologia , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/farmacologia , Humanos , Cinética , NADH NADPH Oxirredutases/antagonistas & inibidores , NADH NADPH Oxirredutases/isolamento & purificação , NADPH Oxidases
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