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1.
Contemp Clin Trials ; 129: 107170, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37019180

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the leading liver disorder among U.S. children and is most prevalent among Hispanic children with obesity. Previous research has shown that reducing the consumption of free sugars (added sugars + naturally occurring sugars in fruit juice) can reverse liver steatosis in adolescents with NAFLD. This study aims to determine if a low-free sugar diet (LFSD) can prevent liver fat accumulation and NAFLD in high-risk children. METHODS: In this randomized controlled trial, we will enroll 140 Hispanic children aged 6 to 9 years who are ≥50th percentile BMI and without a previous diagnosis of NAFLD. Participants will be randomly assigned to either an experimental (LFSD) or a control (usual diet + educational materials) group. The one-year intervention includes removal of foods high in free sugars from the home at baseline, provision of LFSD household groceries for the entire family (weeks 1-4, 12, 24, and 36), dietitian-guided family grocery shopping sessions (weeks 12, 24, and 36), and ongoing education and motivational interviewing to promote LFSD. Both groups complete assessment measures at baseline, 6, 12, 18, and 24 months. Primary study outcomes are percent hepatic fat at 12 months and incidence of clinically significant hepatic steatosis (>5%) + elevated liver enzymes at 24 months. Secondary outcomes include metabolic markers potentially mediating or moderating NAFLD pathogenesis. DISCUSSION: This protocol describes the rationale, eligibility criteria, recruitment strategies, analysis plan as well as a novel dietary intervention design. Study results will inform future dietary guidelines for pediatric NAFLD prevention. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05292352.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Criança , Humanos , Dieta , Hispânico ou Latino , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Açúcares
2.
Int J Nurs Stud ; 116: 103903, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33637295

RESUMO

BACKGROUND AND OBJECTIVE: The number of studies in the area of self-care is growing and international researchers are increasingly developing self-care interventions to improve outcomes of individual patients and communities. However, growth of the evidence is still slow due to challenges with designing and testing self-care interventions. In this article we address major methodological challenges with regard to the definition of self-care, use of theory, and research design, intended to provide guidance to researchers in this field. METHOD: During the inaugural conference of the International Center for Self-Care Research held in Rome, Italy in June 2019 we identified important issues in existing self-care research. Discussion and literature review lead to eight recommendation for future self-care research. RESULTS: In preparation, begin with a theoretically sound definition of self-care. In planning the intervention, build on and extend previous studies. Use theory to develop self-care interventions and consider translational models to guide development, evaluation and implementation of complex self-care interventions. Employ a study design that fits the current phase and objectives of the research and measure self-care and related factors carefully. In reporting, describe the sample and setting sufficiently so that others can draw conclusions about generalizability and applicability to their practice and patient population. In interpretation, describe how the intervention is assumed to work (causal assumptions) and its key components. CONCLUSION: Our review of existing self-care research clearly illustrates that the recommendations we provide are needed if we are to substantially grow the evidence base supporting self-care. Embracing a core set of principles will allow us to build on each other's work. Tweetable abstract: A core set of methodological principles is needed to substantially grow the evidence base supporting self-care.


Assuntos
Autocuidado , Humanos , Itália
3.
J Anal Psychol ; 66(1): 112-131, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33464592

RESUMO

This paper considers the topic of the 'good' within the literature and in clinical work. Milder forms of the good which arise on the personal level generate defences against personal vulnerability. More powerful forms of the good, which the author calls the 'truly good', arise on an archetypal level and overwhelm the ego, generating fear, even terror. The 'truly good' invokes defences against the dissolution of an intact sense of self. In both mild and intense forms, the good will arise in every analysis, will challenge boundaries of both client and analyst, and touch the core of the analytic relationship. It demands acknowledgement. Within these two categories, the author identifies five forms of the good that may arise in containable and uncontainable intensities: beauty, intimacy, becoming, love, and encounters with the divine. Exploring encounters with the good in its various forms expands the range of tolerable human experience - one of the fundamental goals of analysis. Living the good, or at times suffering the truly good, furthers individuation as it enlarges access to experiences of profound meaning, including the divine or the numinous.


Cet article examine le sujet du « bien ¼ dans la littérature et dans la pratique clinique. Les formes modérées du bien qui surviennent au niveau personnel suscitent des défenses contre la vulnérabilité. Les formes plus puissantes du bien, que l'auteur nomme le « bien authentique ¼, se produisent au niveau archétypal et submergent l'égo, suscitant de la peur et même de la terreur. Le « bien authentique ¼ invoque des défenses contre la dissolution d'un sentiment intact du soi. Aussi bien dans ses formes modérées que dans ses formes puissantes, le bien va survenir dans chaque analyse, va mettre au défi les limites du client et de l'analyste, et toucher le cœur de la relation analytique. Il demande à être reconnu. A l'intérieur de ces deux catégories, l'auteur identifie cinq formes de bien qui peuvent survenir avec des intensités possibles ou impossibles à contenir: la beauté, l'intimité, le devenir, l'amour et les rencontres avec le divin. Explorer les rencontres avec le bien dans ses formes diverses élargit l'éventail de l'expérience humaine tolérable - un des buts fondamentaux de l'analyse. Vivre le bien, ou par moment souffrir le bien authentique, fait avancer l'individuation en élargissant l'accès aux expériences qui ont un sens profond, ce qui inclut le divin ou le numineux.


El presente trabajo considera el tema del 'bien' en la literatura y en el trabajo clínico. Formas suavizadas del bien, las cuales emergen a nivel personal generan defensas contra la vulnerabilidad personal. Formas más poderosas del bien, las cuales el autor denomina el 'bien verdadero', emergen desde un nivel arquetípico y abruman al ego, generando miedo, aún terror. El 'verdadero bien' invoca defensas contra la disolución de un sentido del sí mismo intacto. En ambas formas, suave e intensa, el bien emergerá en cada análisis, desafiando los limites de ambos paciente y analista, y tocando el núcleo de la relación analítica. Lo cual demanda reconocimiento. Dentro de estas dos categorías, el autor identifica cinco formas de bien que pueden emerger en intensidades, posibles o no, de ser contenidas: belleza, intimidad, devenir, amor, y encuentro con lo divino. Explorar los encuentros con el bien en su variedad de formas expande el rango de lo tolerable en la experiencia humana - una de las metas fundamentales del análisis. Vivir el bien, o a veces sufrir el verdadero bien, promueve la individuación, en la medida que amplía el acceso a experiencias de sentido profundo, incluyendo lo divino o lo numinoso.


Assuntos
Individuação , Humanos
4.
Int J Nurs Stud ; 105: 103555, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32199150

RESUMO

BACKGROUND AND OBJECTIVE: The number of studies in the area of self-care is growing and international researchers are increasingly developing self-care interventions to improve outcomes of individual patients and communities. However, growth of the evidence is still slow due to challenges with designing and testing self-care interventions. In this article we address major methodological challenges with regard to the definition of self-care, use of theory, and research design, intended to provide guidance to researchers in this field. METHOD: During the inaugural conference of the International Center for Self-Care Research held in Rome, Italy in June 2019 we identified important issues in existing self-care research. Discussion and literature review lead to eight recommendation for future self-care research. RESULTS: In preparation, begin with a theoretically sound definition of self-care. In planning the intervention, build on and extend previous studies. Use theory to develop self-care interventions and consider translational models to guide development, evaluation and implementation of complex self-care interventions. Employ a study design that fits the current phase and objectives of the research and measure self-care and related factors carefully. In reporting, describe the sample and setting sufficiently so that others can draw conclusions about generalizability and applicability to their practice and patient population. In interpretation, describe how the intervention is assumed to work (causal assumptions) and its key components. CONCLUSION: Our review of existing self-care research clearly illustrates that the recommendations we provide are needed if we are to substantially grow the evidence base supporting self-care. Embracing a core set of principles will allow us to build on each other's work. Tweetable abstract: A core set of methodological principles is needed to substantially grow the evidence base supporting self-care.


Assuntos
Enfermagem Baseada em Evidências , Projetos de Pesquisa , Autocuidado , Humanos
5.
J Clin Microbiol ; 56(8)2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29848562

RESUMO

The vertical transmission of group B Streptococcus (GBS) strains causing neonatal sepsis is one of the leading reasons for neonatal mortality worldwide. The gold standard for GBS detection is enriched culture with or without the aid of chromogenic agars. Given the high risk for morbidity and mortality in this population, high assay sensitivity is required to prevent the personal and economic costs of GBS disease. Nucleic acid amplification tests (NAATs) allow for objective determination of GBS colonization with a sensitivity and a specificity higher than those of traditional culture methods. In this study, we determined the analytical and clinical performance of the Aries GBS assay compared to those of the enrichment culture method, biochemical identification, and the NAATs used at the study sites. Remnant Lim broth samples were used to perform the Aries assay and reference testing. Upon first testing using enriched culture as the reference standard, the Aries GBS assay identified GBS with a 96.1% sensitivity (95% confidence interval [CI], 91.2 to 98.7%) and a 91.4% specificity (95% CI, 88.8 to 93.6%). The test performed with 100% positive agreement (95% CI, 83.2 to 100%) compared to the results of the BD Max GBS assay and 98.0% positive agreement (95% CI, 89.2 to 99.9%) compared to the results of the Cepheid Xpert GBS LB test. Repeatability and reproducibility were maintained in intra- and interlaboratory testing, regardless of the instrument, module, or user who performed the test. The Aries GBS assay can be set up in less than 5 min and produces results in 2 h. The easy setup, with minimal hands-on time, and high assay sensitivity and specificity make this a useful testing option for GBS screening in prepartum women.


Assuntos
Complicações Infecciosas na Gravidez/diagnóstico , Diagnóstico Pré-Natal/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Infecções Estreptocócicas/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Técnicas de Diagnóstico Molecular/normas , Gravidez , Terceiro Trimestre da Gravidez , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Streptococcus agalactiae/genética , Fatores de Tempo , Adulto Jovem
6.
J Fish Dis ; 41(4): 581-587, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29468849

RESUMO

Cyprinid herpesvirus 3 (CyHV-3) or koi herpesvirus (KHV) is a virulent viral infection in common carp and koi. The disease has caused global epizootic and economic loss in fish aquaculture and in the wild. Clinacanthus nutans (Burm. f.) Lindau is a well-known medicinal plant used in Thai traditional medicine. Virucidal effects of the plant extract against human herpes simplex virus have been reported. In this study, C. nutans crude extract was tested for antiviral activities against CyHV-3 in koi carp. Results showed effective antiviral activity against CyHV-3 pre- and post-infection. The 50% lethal concentration (LC50 ) of extract was higher than 5 mg/ml. The 50% effective dose (ED50 ) was 0.99 mg/ml, 0.78 mg/ml, 0.75 mg/ml and 0.71 mg/ml at 1, 2, 3 and 4 hr pre-infection, respectively. The ED50 from post-infection tests was 2.05 mg/ml and 2.34 mg/ml at 0 and 24 hr, respectively. These results demonstrated that crude extract expressed antiviral activity against CyHV-3 and can be applied as a therapeutic agent in common carp and koi aquaculture.


Assuntos
Acanthaceae/química , Antivirais/uso terapêutico , Carpas , Doenças dos Peixes/tratamento farmacológico , Infecções por Herpesviridae/veterinária , Herpesviridae/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Doenças dos Peixes/virologia , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/virologia
7.
Clin Obes ; 7(2): 77-85, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28117927

RESUMO

In patients with heart failure (HF), higher body mass index (BMI) has been associated with lower rates of hospitalization and mortality (obesity paradox). Symptoms are antecedents of hospitalizations, but little is known about the relationship between BMI and symptoms and gender differences. To examine the association of BMI with symptoms in male and female patients with HF, controlling for covariates (sample characteristics, depressive symptoms and sodium intake). In this cross-sectional correlational study, patients (N = 247) provided data on BMI, symptoms and covariates. BMI was categorized into four groups: normal/underweight (<25 kg/m2 ), overweight (25-29.9 kg/m2 ), obese I (30-34.9 kg/m2 ) and obese II/III (≥35 kg/m2 ). General linear regression was used to analyse the data. The Obese II/III group had more severe HF symptoms than other groups only in male patients. In male patients, older age, Caucasian race, more comorbidities and more severe depressive symptoms were also associated with more severe symptoms. In female patients, more severe depressive symptoms, more comorbidities and higher sodium intake were associated with more severe symptoms. The obesity paradox does not fully extend to symptoms, and gender has a role in the relationship between obesity and symptoms.


Assuntos
Índice de Massa Corporal , Insuficiência Cardíaca/etiologia , Obesidade/complicações , Fatores Sexuais , Fatores Etários , Idoso , Estudos Transversais , Depressão/complicações , Feminino , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/psicologia , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Fatores de Risco , População Branca
8.
J Neurol Surg B Skull Base ; 76(1): 35-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25685647

RESUMO

Objective To establish a consistent surface bony landmark for a middle fossa approach (MFA) lateral craniotomy represented by the squamosal suture (SS). Methods In 60 dried skulls, we assessed the relation between the SS and the external auditory canal (EAC). The lateral portion of the middle cranial fossa floor was also assessed for a possible relation with the anteroposterior diameter (APD) of the squama temporalis (ST). Clinically, we applied our findings on the SS in MFA for different lesions. Results A vertical line at the EAC divided the ST into the anterior part constituting 61% of the APD (i.e., two thirds) and the posterior part forming 39% (i.e., one third). The average ST height was 35.92 mm. The SS posterior limit at the supramastoid crest was located just anterior to the external projection of the petrous ridge in 35 skulls (58%) and exactly corresponded to it in 25 skulls (42%). The APD of the ST equals on average 97% of the APD of the lateral middle cranial fossa. Optimum exposure of the middle fossa was obtained without any further craniotomy extension. Conclusion The SS serves as a consistent natural surface bony landmark for MFA. Optimum craniotomy, two thirds anterior to the EAC and one third posterior, is obtained following SS as a landmark.

9.
Int. braz. j. urol ; 37(5): 664-664, Sept.-Oct. 2011.
Artigo em Inglês | LILACS | ID: lil-608141
10.
Insect Mol Biol ; 13(2): 205-11, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15056368

RESUMO

Inducible, vector-based, expression systems that allow fine control of transgene expression are gaining more and more use in fundamental research as well as in therapeutic applications. In an effort to develop a tightly regulated heterologous expression system for Drosophila Schneider 2 cells, three different inducible reporter constructs were compared. These comprised six copies of the glucocorticoid response element fused to one of three distinct types of Drosophila gene promoters: (1) a TATA-box containing, (2) a TATA-less and (3) a bidirectional core sequence. These were fused to a luciferase reporter gene. The promoter constructs displayed different basal as well as agonist-induced activities. The implications of the observations made are discussed in the context of promoter properties and of induction of genes that may be studied in Drosophila.


Assuntos
Drosophila melanogaster/genética , Regulação da Expressão Gênica/genética , Genes Reporter/genética , Vetores Genéticos/genética , Glucocorticoides/metabolismo , Animais , Células Cultivadas , Primers do DNA , Vetores Genéticos/metabolismo , Luciferases/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Transgenes/genética
11.
Br J Anaesth ; 91(3): 427-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12925486

RESUMO

BACKGROUND: Direct or indirect acting cholinergic muscarinic agonists such as neostigmine, are potent antinociceptives when administered intrathecally (i.t.). This study examines whether spinal neostigmine tolerance and cross-tolerance to spinal morphine occurs. METHODS: Rats (32/group) were implanted with miniosmotic pumps delivering either i.t. saline 1 microl h(-1) (S), morphine 10 nmol microl(-1) h(-1) (M), or neostigmine 3 nmol microl(-1) h(-1) (N). Latencies (infrared thermal withdrawal rear paw) were measured daily for 6 days after which four animals from each group were given one i.t. challenge dose of morphine (m) 0.1, 1, 10, or 100 nmol, or neostigmine (n) 0.3, 3, 10, or 30 nmol. RESULTS: Neostigmine and morphine-infused animals both developed tolerance to spinal neostigmine, but neostigmine-infused animals showed no significant cross-tolerance to spinal morphine; mean ED(50) nmol (CI 95%) dose-response values were Sn 2.6 (1.9-3.5), Mn 15.6 (9.9-24.6)*, Nn 18.7 (11.7-29.8)*, Sm 0.7 (0.4-1.1), Nm 1.2 (0.8-2.0), Mm 152 (50-461)* (*significance vs saline infused control group). CONCLUSION: Thus, unidirectional cross-tolerance from morphine to neostigmine was evident. Previous studies suggest morphine has a cholinergic mechanism of action partially accounting for its antinociceptive effect, which may explain this observed unidirectional cross-tolerance.


Assuntos
Analgésicos Opioides/farmacologia , Inibidores da Colinesterase/farmacologia , Morfina/farmacologia , Neostigmina/farmacologia , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Interações Medicamentosas , Tolerância a Medicamentos , Bombas de Infusão , Injeções Espinhais , Masculino , Medição da Dor/métodos , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos
12.
Appl Microbiol Biotechnol ; 59(2-3): 318-24, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12111164

RESUMO

In this report we examined the structure and properties of surface-active lipids of Rhodococcus ruber. Most historical interest has been in the glycolipids of Rhodococcus erythropolis, which have been extensively characterised. R. erythropolis has been of interest due to its great metabolic diversity. Only recently has the metabolic potential of R. ruber begun to be explored. One major difference in the two species is that most R. ruber strains are able to oxidise the gaseous alkanes propane and butane. In preparation for investigation of the effects of gas metabolism on biosurfactant production, we set out to characterise the biosurfactants produced during growth on liquid n-alkanes and to compare these with R. erythropolis glycolipids.


Assuntos
Rhodococcus/metabolismo , Tensoativos/metabolismo , Alcanos/metabolismo , Glicolipídeos/química , Espectroscopia de Ressonância Magnética , Nitratos/metabolismo , Rhodococcus/crescimento & desenvolvimento , Tensoativos/química
13.
Am J Physiol Heart Circ Physiol ; 281(3): H1170-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514284

RESUMO

Microgravity is associated with an impaired stroke volume and, therefore, cardiac output response to orthostatic stress. We hypothesized that a decreased venous filling pressure due to increased venous compliance may be an important contributing factor in this response. We used a constant flow, constant right atrial pressure cardiopulmonary bypass procedure to measure total systemic vascular compliance (C(T)), arterial compliance (C(A)), and venous compliance (C(V)) in seven control and seven 21-day hindlimb unweighted (HLU) rats. These compliance values were calculated under baseline conditions and during an infusion of 0.2 microg*kg(-1)*min(-1) norepinephrine (NE). The change in reservoir volume, which reflects changes in unstressed vascular volume (DeltaV(0)) that occurred upon infusion of NE, was also measured. C(T) and C(V) were larger in HLU rats both at baseline and during the NE infusion (P < 0.05). Infusion of NE decreased C(T) and C(V) by ~20% in both HLU and control rats (P < 0.01). C(A) was also significantly decreased in both groups of rats by NE (P < 0.01), but values of C(A) were similar between HLU and control rats both at baseline and during the NE infusion. Additionally, the NE-induced DeltaV(0) was attenuated by 53% in HLU rats compared with control rats (P < 0.05). The larger C(V) and attenuated DeltaV(0) in HLU rats could contribute to a decreased filling pressure during orthostasis and thus may partially underlie the mechanism leading to the exaggerated fall in stroke volume and cardiac output seen in astronauts during an orthostatic stress after exposure to microgravity.


Assuntos
Membro Posterior/irrigação sanguínea , Membro Posterior/fisiologia , Capacitância Vascular/fisiologia , Ausência de Peso , Animais , Artérias/fisiologia , Volume Sanguíneo , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Compartimentos de Líquidos Corporais/fisiologia , Peso Corporal/fisiologia , Ponte Cardiopulmonar/instrumentação , Ponte Cardiopulmonar/métodos , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Masculino , Norepinefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Capacitância Vascular/efeitos dos fármacos , Veias/fisiologia
14.
Heart Lung ; 30(4): 312-20, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11449218

RESUMO

OBJECTIVE: The purpose of this study was to pilot test a self-administered chest pain questionnaire, a revised version of the Chest Discomfort Diary (CDD-R), in a sample of patients with chronic angina selected from a population known to have low literacy. DESIGN: The study design was descriptive and correlational. SAMPLE: The study used a convenience sample of 27 subjects with documented history of coronary artery disease and angina. Characteristics of the sample included a mean age of 56.3 years (SD, 12.4 years), 88.9% African-American, and 56.3% male, and 59.3% had a history of acute myocardial infarction. Approximately 28% had achieved a 9th-grade education or less, and reading levels ranged from 4th grade to 12th grade. Subjects completed the CDD-R, a 36-item instrument reflecting multiple dimensions of anginal chest pain. RESULTS: Descriptions of the location (left chest, 66.6%), character (pressure, 59.2%), and precipitants of chest pain (walking, 51.8%) were consistent with clinical descriptions of "typical angina." Other physical symptoms such as shortness of breath (88.8%) and fatigue (85.1%) were reported. Walking (55.5%) was the activity most frequently described as difficult to perform because of chest pain, with sublingual nitroglycerin (77.7%) the most frequently used and most effective chest pain relief strategy. CONCLUSION: The CDD-R adequately measured multiple characteristics of anginal chest pain. Further research is needed to establish construct validity of the CDD-R and to determine the feasibility of using the instrument to monitor changes over time in patients' chronic angina.


Assuntos
Dor no Peito/epidemiologia , Dor no Peito/etiologia , Escolaridade , Programas de Rastreamento/instrumentação , Medição da Dor/instrumentação , Inquéritos e Questionários , Adulto , Negro ou Afro-Americano/educação , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Angina Pectoris/diagnóstico , Angina Pectoris/epidemiologia , Doença Crônica , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Avaliação Educacional/métodos , Avaliação Educacional/estatística & dados numéricos , Feminino , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Medição da Dor/métodos , Educação de Pacientes como Assunto/estatística & dados numéricos , Participação do Paciente , Projetos Piloto , Autoavaliação (Psicologia) , Sudeste dos Estados Unidos/epidemiologia
15.
J Microbiol Methods ; 46(2): 149-56, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11412925

RESUMO

In the present study, we proposed methyl tertiary-butyl ether (MTBE) as a solvent for extraction of biosurfactants from Rhodococcus bacterial cultures. After comparison with other well known solvent systems used for biosurfactant extraction, it was found that MTBE was able to extract crude surfactant material with high product recovery (10 g/l), efficiency (critical micelle concentration (CMC), 130-170 mg/l) and good functional surfactant characteristics (surface and interfacial tensions, 29 and 0.9 mN/m, respectively). The isolated surfactant complex contained 10% polar lipids, mostly glycolipids possessing maximal surface activity. Ultrasonic treatment of the extraction mixture increased the proportion of polar lipids in crude extract, resulting in increasing surfactant efficiency. Due to certain characteristics of MTBE, such as relatively low toxicity, biodegradability, ease of downstream recovery, low flammability and explosion safety, the use of this solvent as an extraction agent in industrial scale biosurfactant production is feasible.


Assuntos
Éteres Metílicos , Rhodococcus/isolamento & purificação , Solventes , Glicolipídeos/análise , Tensoativos/isolamento & purificação
16.
Clin Infect Dis ; 32(10): 1511-5, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11317256

RESUMO

Difficulties in distinguishing organisms of the "Streptococcus milleri group" (SMG; Streptococcus intermedius, Streptococcus constellatus, and Streptococcus anginosus), have caused ambiguity in determining their pathogenic potential. We reviewed 118 cases in which SMG isolates had been identified using 16S rDNA sequence. S. constellatus and S. anginosus were isolated far more frequently than was S. intermedius. Nearly all isolates of S. intermedius and most isolates of S. constellatus, but only 19% of those of S. anginosus, were associated with abscess. Our findings suggest that speciation of the SMG may guide diagnostic evaluation, give insight into the possible role of coinfecting organisms, and help assess the need to search for occult abscess.


Assuntos
Abscesso , RNA Ribossômico 16S/genética , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Streptococcus/patogenicidade , Genes de RNAr , Humanos , Análise de Sequência de DNA , Streptococcus/genética
18.
J Membr Biol ; 179(2): 127-41, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11220363

RESUMO

The existence of invertebrate forms of the RyR has recently been confirmed (Takeshima et al., 1994, Puente et al., 2000). However, information on the functional properties of this insect RyR is still limited. We report the functional characterization of a RyR from the thoracic muscle of H. virescens (Scott-Ward et al., 1997). A simple purification protocol produced membranes from homogenized prefrozen H. virescens thoracic muscle with a [3H]-ryanodine binding activity of 1.19 +/- 0.21 pmol/mg protein (mean +/- SE; n = 4). [3H]-Ryanodine binding to the H. virescens receptor was dependent on the ryanodine concentration in a hyperbolic fashion with a KD of 3.82 nM (n = 4). [3H]-ryanodine binding was dependent on [Ca2+] in a biphasic manner and was stimulated by 1 mM ATP. Millimolar caffeine did not stimulate [3H]-ryanodine binding to H. virescens membranes in the presence of either nanomolar or micromolar Ca2+. A protein of at least 400 KDa was recognized in H. virescens membrane proteins by a specific anti-H. virescens RyR antibody. Discontinuous density sucrose gradient fractionation of microsomal membranes produced vesicles suitable for single-channel studies. Ca2+-sensitive, Ca2+-permeable channels were successfully inserted into artificial lipid bilayers from H. virescens membrane vesicles. The H. virescens RyR-channel displayed a Ca2+ conductance of approximately 110 pS and underwent a persistent and characteristic modification of ion handling and gating following addition of 100 nM ryanodine. The gating of H. virescens channels was sensitive to ATP and ruthenium red in a manner similar to mammalian RyR. This is the first report to describe the single channel and [3H]-ryanodine binding properties of a native insect RyR.


Assuntos
Proteínas de Insetos/metabolismo , Mariposas/metabolismo , Músculo Esquelético/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Rianodina/metabolismo , Animais , Cafeína/farmacologia , Cálcio/metabolismo , Fracionamento Celular , Estimulantes do Sistema Nervoso Central/farmacologia , Quelantes/farmacologia , Ácido Egtázico/farmacologia , Eletrofisiologia , Immunoblotting , Indicadores e Reagentes/farmacologia , Proteínas de Insetos/química , Cinética , Magnésio/metabolismo , Microssomos/metabolismo , Músculo Esquelético/química , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Coelhos , Ensaio Radioligante , Rutênio Vermelho/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Tórax/metabolismo , Trítio/metabolismo
19.
Insect Mol Biol ; 10(6): 541-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11903623

RESUMO

The LCR/MEL system (Locus Control Region/Murine Erythroleukaemia cells) was employed to express and characterize the Locusta migratoria tyramine receptor (TyrLoc), an insect G protein-coupled receptor. Functional agonist-dependent responses were recorded in stable, tyramine receptor expressing cell clones (MEL-TyrLoc). Tyramine elicited a dose-dependent increase of cytosolic Ca2+-ions and an attenuation of forskolin-induced cyclic adenosine monophosphate (AMP) production. Octopamine was shown to be a weak agonist for both responses. In addition, yohimbine proved to be a potent tyramine receptor antagonist. This study reports the first application of the LCR/MEL expression system in functional assays for G protein-coupled receptors and therefore expands the capabilities of this system by exploiting the functionality of the signal transduction pathways.


Assuntos
Expressão Gênica , Gafanhotos/genética , Receptores de Amina Biogênica/genética , Animais , Sequência de Bases , Cálcio , AMP Cíclico , DNA Complementar , Leucemia Eritroblástica Aguda , Camundongos , Dados de Sequência Molecular , Células Tumorais Cultivadas
20.
Int J Psychiatry Med ; 31(4): 375-87, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11949736

RESUMO

OBJECTIVE: To describe psychological reactions among family members of patients receiving an implantable cardioverter/defibrillator (ICD) during the first 9 months after implantation. METHODS: Eighty-two family members (age 56+/-12 years, 74 percent female, 79 percent married, 88 percent Caucasian) of ICD patients completed questionnaires regarding their mood (Profile of Mood State), cognitive illness appraisals (Meaning of Illness Questionnaire) and coping strategies (Jalowiec Coping Scale) prior to ICD implantation, and as well as 1 and 9 months postoperatively. RESULTS: Total mood disturbance score (TMD), threat appraisal, and emotion- and problem-focused coping were highest prior to ICD implantation, and decreased during the first postoperative month showing stable values thereafter. There was no change in challenge appraisal. Multiple regression analysis found that the use of psychotropic drugs (anxiolytics, sedatives; Beta = .25), emotion-focused coping (Beta = .37), and challenge appraisal (Beta =-.21) at 1 month accounted for 26 percent of variance in TMD at 9 mon ths. CONCLUSION: A spouse's ICD implantation is a major stressful event for family members leading to a diminished mood state prior ICD implantation. Reduction in emotion-focused coping and the use of challenge appraisal may improve mood state in family members of ICD patients during early follow-up.


Assuntos
Desfibriladores Implantáveis/psicologia , Família/psicologia , Pacientes/psicologia , Adaptação Psicológica , Adulto , Afeto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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