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1.
Cephalalgia ; 37(8): 737-755, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27226003

RESUMO

Background Familial hemiplegic migraine (FHM) is a rare monogenic migraine subtype characterised by attacks associated with transient motor weakness. Clinical information is mainly based on reports of small families with only short follow-up. Here, we document a prospective 15-year follow-up of an extended family with FHM type 2. Patients and methods After diagnosing FHM in a patient with severe attacks associated with coma and fever, we identified eight more family members with FHM and one with possible FHM. All family members were prospectively followed for 15 years. In total 13 clinically affected and 21 clinically non-affected family members were genetically tested and repeatedly investigated. Results A novel p.Arg348Pro ATP1A2 mutation was found in 14 family members: 12 with clinical FHM, one with psychomotor retardation and possible FHM, and one without FHM features. In 9/12 (75%) family members with genetically confirmed FHM, attacks were severe, long-lasting, and often associated with impaired consciousness and fever. Such attacks were frequently misdiagnosed and treated as viral meningitis or stroke. Epilepsy was reported in three family members with FHM and in the one with psychomotor retardation and possible FHM. Ataxia was not observed. Conclusion FHM should be considered in patients with recurrent coma and fever.


Assuntos
Enxaqueca com Aura/genética , ATPase Trocadora de Sódio-Potássio/genética , Coma/genética , Feminino , Febre/genética , Seguimentos , Humanos , Masculino , Enxaqueca com Aura/complicações , Mutação , Linhagem , Estudos Prospectivos
2.
Horm Metab Res ; 48(12): 814-821, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27813051

RESUMO

Salivary cortisol has been used to monitor hydrocortisone replacement in patients with Addison's disease (AD). Since salivary cortisol is metabolised to salivary cortisone, it may be an adjunctive analyte to assess adequacy of hydrocortisone replacement in patients with AD. We aimed to characterise the exposure of salivary cortisol and cortisone in patients and healthy controls. We measured salivary cortisol and cortisone by liquid chromatography-tandem mass spectrometry and constructed a day curve (08:00 until 24:00 h) with 16 time points in 25 AD patients taking their usual hydrocortisone dose and in 26 healthy controls. The median (interquartile range) area under the curve (AUC) for cortisol was not different for patients, compared with controls [55.63 (32.91-151.07) nmol*min*l-1 vs. 37.49 (27.41-52.00) nmol*min*l-1; p=0.098, respectively], whereas the peak cortisol Cmax was higher in patients [32.61 (5.75-146.19) nmol/l vs. 8.96 (6.96-12.23) nmol/l; p=0.013], compared with controls. The AUC for cortisone [23.65 (6.10-54.76) nmol*min*l-1 vs. 227.73 (200.10-280.52) nmol*min*l-1; p≤ 0.001, respectively], and peak cortisone Cmax was lower in patients than in controls [11.11 (2.91-35.85) nmol/l vs. 33.12 (25.97-39.95) nmol/l; p=0.002]. The AUC for salivary cortisol and salivary cortisone were not correlated with any measures of hydrocortisone dose. The time-course and AUC of salivary cortisol were similar between Addison's patients and healthy controls. Patients had substantially lower salivary cortisone AUC, compared to healthy controls. Salivary cortisol AUC and pharmacokinetics were not related to hydrocortisone dose and thus are not likely useful markers for the adequacy of hydrocortisone replacement.


Assuntos
Doença de Addison/tratamento farmacológico , Cortisona/metabolismo , Terapia de Reposição Hormonal , Hidrocortisona/metabolismo , Hidrocortisona/uso terapêutico , Saliva/metabolismo , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Cortisona/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
3.
Crit Rev Clin Lab Sci ; 51(1): 46-62, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24405372

RESUMO

Atherosclerosis is strongly associated with dyslipoproteinaemia, and especially with increasing concentrations of low-density lipoprotein and decreasing concentrations of high-density lipoproteins. Its association with increasing concentrations of plasma triglyceride is less clear but, within the mixed hyperlipidaemias, dysbetalipoproteinaemia (Fredrickson type III hyperlipidaemia) has been identified as a very atherogenic entity associated with both premature ischaemic heart disease and peripheral arterial disease. Dysbetalipoproteinaemia is characterized by the accumulation of remnants of chylomicrons and of very low-density lipoproteins. The onset occurs after childhood and usually requires an additional metabolic stressor. In women, onset is typically delayed until menopause. Clinical manifestations may vary from no physical signs to severe cutaneous and tendinous xanthomata, atherosclerosis of coronary and peripheral arteries, and pancreatitis when severe hypertriglyceridaemia is present. Rarely, mutations in apolipoprotein E are associated with lipoprotein glomerulopathy, a condition characterized by progressive proteinuria and renal failure with varying degrees of plasma remnant accumulation. Interestingly, predisposing genetic causes paradoxically result in lower than average cholesterol concentration for most affected persons, but severe dyslipidaemia develops in a minority of patients. The disorder stems from dysfunctional apolipoprotein E in which mutations result in impaired binding to low-density lipoprotein (LDL) receptors and/or heparin sulphate proteoglycans. Apolipoprotein E deficiency may cause a similar phenotype. Making a diagnosis of dysbetalipoproteinaemia aids in assessing cardiovascular risk correctly and allows for genetic counseling. However, the diagnostic work-up may present some challenges. Diagnosis of dysbetalipoproteinaemia should be considered in mixed hyperlipidaemias for which the apolipoprotein B concentration is relatively low in relation to the total cholesterol concentration or when there is significant disparity between the calculated LDL and directly measured LDL cholesterol concentrations. Genetic tests are informative in predicting the risk of developing the disease phenotype and are diagnostic only in the context of hyperlipidaemia. Specialised lipoprotein studies in reference laboratory centres can also assist in diagnosis. Fibrates and statins, or even combination treatment, may be required to control the dyslipidaemia.


Assuntos
Apolipoproteínas E/genética , Hiperlipoproteinemia Tipo III , Humanos , Mutação
4.
Horm Metab Res ; 46(10): 691-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24799025

RESUMO

Hypogonadism may complicate Addison's disease (primary hypoadrenalism), but prevalence and metabolic sequelae of hypogonadism in Addison's disease are poorly described. We recruited patients from the South African Addison's disease national registry who received stable replacement doses of hydrocortisone and had no acute illness. Male biochemical testosterone deficiency was defined as an early morning basal testosterone<9.9 nmol/l and premature ovarian failure (POF) when menopause occurred before 40 years of age. Cardiometabolic risk variables were measured in males only. Male hypogonadism prevalence was 33% (14/42), and 10 patients had newly diagnosed hypogonadism. Two untreated patients had elevated FSH or LH (>10 or 12 IU/l). Testosterone deficiency did not correlate with age, disease duration or hydrocortisone dose. Untreated male hypogonadal subjects had a higher (mean ± standard deviation) BMI compared to eugonadal subjects 29.2 ± 4.9 kg/m(2) vs. 24.7 ± 3.4 kg/m(2) (p=0.01) and a higher median (interquartile range) high-sensitive-CRP 6.4 (2.5-14.0) mg/l vs. 1.45 (0.6-2.8) mg/l (p=0.002). There were no differences between the 2 groups in lipids, lipoproteins and fasting glucose. The median (interquartile range) DHEAS was lower in the hypogonadal 0.31 (0.27-0.37) µmol/l, compared with the eugonadal group 0.75 (0.50-1.51) µmol/l (p=0.005). POF was documented in 11% of female patients. Male testosterone deficiency was highly prevalent in this cohort and was primarily due to secondary hypogonadism. Only BMI and hs-CRP were increased in untreated male hypogonadal subjects. Male and female hypogonadism appears to be a common complication of Addison's disease and may contribute to its morbidity.


Assuntos
Doença de Addison/complicações , Hipogonadismo/epidemiologia , Hipogonadismo/etiologia , Doença de Addison/sangue , Adulto , Idoso , Proteína C-Reativa/metabolismo , Estudos de Coortes , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hipogonadismo/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , África do Sul/epidemiologia , Testosterona/sangue
5.
Clin Exp Rheumatol ; 32(3): 308-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24708914

RESUMO

OBJECTIVES: Health care and vocational professionals regularly encounter patients with rheumatic diseases who are embittered after a disability pension examination. People who are embittered typically feel victimised, experience resentment and injustice, resist help, and have difficulty coping. Our objective was to examine the occurrence of embitterment in patients with rheumatic diseases after a disability pension examination and the association of embitterment with its possible determinants helplessness and illness invalidation at work. METHODS: The Illness Cognition Questionnaire (ICQ), Illness Invalidation Inventory (3*I), and Bern Embitterment Inventory were completed by patients who had 9 to 12 weeks earlier received the result of a disability pension examination. Diagnoses were fibromyalgia (n=103), rheumatoid arthritis (n=46), osteoarthritis (n=158), another rheumatic disease (n=62), and more than one rheumatic disease (n=187). Scores were compared to scores of reference groups. Hierarchical regression analyses were conducted. RESULTS: Eighteen to 27 percent of patients had high levels of embitterment with no differences between diagnostic groups (p=0.71). Helplessness (p<0.001), the two invalidation dimensions discounting and lack of understanding (p<0.001), and the combination of helplessness with these invalidation dimensions (p<0.01), were predictive of more embitterment. CONCLUSIONS: Our results suggest that, after a disability pension examination, embitterment is present in about one out of five patients with a rheumatic disease. This is problematic insofar as embitterment limits well-being, functioning, and the potential to reintegrate to work. To the extent that helplessness and invalidation at work are causal determinants of embitterment, interventions targeting these aspects may be key to reduce embitterment.


Assuntos
Hostilidade , Seguro por Deficiência , Doenças Musculoesqueléticas/psicologia , Doenças Reumáticas/psicologia , Indenização aos Trabalhadores , Adulto , Feminino , Desamparo Aprendido , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/economia , Pensões , Doenças Reumáticas/economia , Apoio Social , Inquéritos e Questionários
6.
Environ Microbiol ; 13(11): 3047-58, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21933319

RESUMO

Recent studies have suggested that bacterial volatiles play an important role in bacterial-plant interactions. However, few reports of bacterial species that produce plant growth modulating volatiles have been published, raising the question whether this is just an anecdotal phenomenon. To address this question, we performed a large screen of strains originating from the soil for volatile-mediated effects on Arabidopsis thaliana. All of the 42 strains tested showed significant volatile-mediated plant growth modulation, with effects ranging from plant death to a sixfold increase in plant biomass. The effects of bacterial volatiles were highly dependent on the cultivation medium and the inoculum quantity. GC-MS analysis of the tested strains revealed over 130 bacterial volatile compounds. Indole, 1-hexanol and pentadecane were selected for further studies because they appeared to promote plant growth. None of these compounds triggered a typical defence response, using production of ethylene and of reactive oxygen species (ROS) as read-outs. However, when plants were challenged with the flg-22 epitope of bacterial flagellin, a prototypical elicitor of defence responses, additional exposure to the volatiles reduced the flg-22-induced production of ethylene and ROS in a dose-dependent manner, suggesting that bacterial volatiles may act as effectors to inhibit the plant's defence response.


Assuntos
Arabidopsis/microbiologia , Bactérias/química , Rizosfera , Microbiologia do Solo , Compostos Orgânicos Voláteis/farmacologia , Alcanos/química , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Meios de Cultura , Etilenos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hexanóis/química , Indóis/química , Reguladores de Crescimento de Plantas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
7.
Int J Obes (Lond) ; 35(4): 605-17, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20733586

RESUMO

OBJECTIVE: The gene TSPAN8 was recently identified in a genome-wide association study as the most likely causal gene in a locus that was correlated with the risk of type 2 diabetes (T2D) in northern European individuals. To assess whether Tspan8 is the actual T2D-causal gene in this locus, we ablated its expression in mice and determined the consequences of this ablation on a multitude of metabolic traits. RESULTS: We found that genetic ablation of Tspan8 in mice results in a reduction (-15.6%) in the body weight of males fed a normal chow diet and that this deficiency results in a resistance to body weight gain (-13.7%) upon feeding a high fat and high carbohydrate diet. The differences in body weight could only be detected in male mice and were the consequence of both a decrease in fat deposition, and a decrease in lean body mass (16.9 and 11%, respectively). In spite of the significant body weight difference, no changes in fasting insulin and glucose levels could be detected in Tspan8 knockout mice, nor could we identify changes in the clearance of glucose or sensitivity to insulin in oral glucose tolerance test and intraperitoneal insulin sensitivity test studies, respectively. In addition, male Tspan8 knockout mice showed significantly lower bone mineral density and phosphorus levels (6.2 and 16.6%, respectively). Expression of Tspan8 in mouse was highest in digestive tissues, but virtually absent from the pancreas. In contrast, expression of human TSPAN8 was substantial in digestive tissues, as well as pancreatic cells. CONCLUSIONS: Our results argue for a role for Tspan8 in body-weight regulation in males, but do not show differences in T2D-associated traits that were anticipated from previous human genome-wide association studies. Differences in Tspan8 expression levels in mouse and human tissues suggest that Tspan8 could fulfill different or additional physiological functions in these organisms.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina/fisiologia , Glicoproteínas de Membrana/deficiência , Obesidade/metabolismo , Animais , Antígenos de Neoplasias/genética , Peso Corporal/fisiologia , Diabetes Mellitus Tipo 2/genética , Feminino , Estudo de Associação Genômica Ampla , Resistência à Insulina/genética , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Fatores Sexuais , Tetraspaninas
8.
J Hosp Infect ; 71(2): 123-31, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19108932

RESUMO

It is not clear whether improvement in environmental decontamination is more efficiently achieved through changes in cleaning products, cleaning procedures, or performance of cleaning personnel. To assess the impact of cleaning performance on environmental contamination with vancomycin-resistant enterococci (VRE), we conducted a sequential trial in which a multifaceted environmental cleaning improvement intervention was introduced in a medical intensive care unit and respiratory step-down unit. The intervention included educational lectures for housekeepers and an observational programme of their activities without changes in cleaning products or written procedures. Following these interventions, the proportion of environmental sites cleaned improved from 49% to 85% (P<0.001); contamination of environmental sites declined from 21% to 8% (P<0.0001) before cleaning and from 13% to 8% (P<0.0001) after cleaning. The improved cleaning and contamination rates persisted in a washout period. In a multivariate model, cleaning thoroughness strongly influenced the degree of environmental contamination, with a 6% decline in VRE prevalence with every 10% increase in percentage of sites cleaned. These findings suggest that surface contamination with VRE is due to a failure to clean rather than to a faulty cleaning procedure or product.


Assuntos
Descontaminação/métodos , Contaminação de Equipamentos/prevenção & controle , Fômites/microbiologia , Zeladoria Hospitalar/métodos , Controle de Infecções/métodos , Resistência a Vancomicina , Descontaminação/normas , Desinfetantes , Enterococcus/efeitos dos fármacos , Enterococcus/isolamento & purificação , Zeladoria Hospitalar/normas , Humanos , Unidades de Terapia Intensiva
10.
Appl Environ Microbiol ; 74(5): 1376-84, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18192425

RESUMO

The actinobacterium Kineococcus radiotolerans is highly resistant to ionizing radiation, desiccation, and oxidative stress, though the underlying biochemical mechanisms are unknown. The purpose of this study was to explore a possible linkage between the uptake of transition metals and extreme resistance to ionizing radiation and oxidative stress. The effects of six different divalent cationic metals on growth were examined in the absence of ionizing radiation. None of the metals tested were stimulatory, though cobalt was inhibitory to growth. In contrast, copper supplementation dramatically increased colony formation during chronic irradiation. K. radiotolerans exhibited specific uptake and intracellular accumulation of copper, compared to only a weak response to both iron and manganese supplementation. Copper accumulation sensitized cells to hydrogen peroxide. Acute-irradiation-induced DNA damage levels were similar in the copper-loaded culture and the age-synchronized no-copper control culture, though low-molecular-weight DNA was more persistent during postirradiation recovery in the Cu-loaded culture. Still, the estimated times for genome restoration differed by only 2 h between treatments. While we cannot discount the possibility that copper fulfills an unexpectedly important biochemical role in a low-radioactivity environment, K. radiotolerans has a high capacity for intracellular copper sequestration and presumably efficiently coordinated oxidative stress defenses and detoxification systems, which confers cross-protection from the damaging effects of ionizing radiation.


Assuntos
Actinomycetales/crescimento & desenvolvimento , Actinomycetales/metabolismo , Actinomycetales/efeitos da radiação , Cobre/farmacocinética , Reparo do DNA/efeitos da radiação , Raios gama , Actinomycetales/ultraestrutura , Eletroforese em Gel de Campo Pulsado , Espectrometria de Massas , Microscopia Eletrônica , Estresse Oxidativo/efeitos da radiação
12.
S Afr Med J ; 108(11b): 973-1000, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30421699

RESUMO

South Africa (SA) is home to a heterogeneous population with a wide range of cardiovascular risk factors. Cholesterol reduction in combination with aggressive management of modifiable risk factors, including nutrition, physical activity, blood pressure and smoking, can help to reduce and prevent morbidity and mortality in individuals who are at increased risk of cardiovascular events. This updated consensus guide to management of dyslipidaemia in SA is based on the updated European Society of Cardiology and European Atherosclerosis Society dyslipidaemia guidelines published in 2016. For individuals who are not considered to be at high or very high cardiovascular risk, the decision whether to treat and which interventional strategy to use is based on a cardiovascular risk score calculated using total cholesterol, high-density lipoprotein cholesterol (HDL-C), gender, age and smoking status. The cardiovascular risk score refers to the 10-year risk of any cardiovascular event and includes 4 categories of risk (low, moderate, high and very high). People with established cardiovascular disease, diabetes mellitus, chronic kidney disease and genetic or severe dyslipidaemias are considered to already be at high or very high risk and do not require risk scoring. Therapeutic lifestyle change is the mainstay of management for all patients. The need for and intensity of drug therapy is determined according to baseline low-density lipoprotein (LDL-C) levels and the target LDL-C concentration appropriate to the individual. LDL-C treatment targets are based on pre-treatment risk and are as follows: <3 mmol/L in low- and moderate risk cases; <2.5 mmol/L and a reduction of at least 50% if the baseline concentration is 2.5 - 5.2 mmol/L in high-risk cases; and <1.8 mmol/L and a reduction of at least 50% if the baseline concentration is 1.8 - 3.5 mmol/L in very high-risk cases. A statin is usually recommended first-line; the specific agent is based on the required degree of cholesterol reduction, comorbidities and co-prescribed medication. Special attention should be paid to children with a family history of genetic or severe dyslipidaemia, who should be screened for dyslipidaemia from 8 years of age. In SA, HIV infection is not considered to be a significant cardiovascular risk factor and treatment recommendations for HIV-positive individuals are the same as for the general population, with careful choice of pharmacotherapy to avoid potential adverse drug-drug interactions. The benefit of statins in individuals older than 70 years is uncertain and clinical judgement should be used to guide treatment decisions and to avoid side-effects and overmedication in this group.


Assuntos
Doenças Cardiovasculares , Dislipidemias , Inibidores de Hidroximetilglutaril-CoA Redutases , Programas de Rastreamento/métodos , Administração dos Cuidados ao Paciente , Comportamento de Redução do Risco , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/psicologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Consenso , Dislipidemias/sangue , Dislipidemias/epidemiologia , Dislipidemias/terapia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Administração dos Cuidados ao Paciente/métodos , Administração dos Cuidados ao Paciente/normas , Medição de Risco/métodos , Fatores de Risco , África do Sul
13.
Cochrane Database Syst Rev ; (1): CD004881, 2007 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-17253528

RESUMO

BACKGROUND: Acute bronchiolitis in infants and young children is associated with long-term airway disease also known as post-bronchiolitic wheezing. Two major hypotheses have been proposed to explain the association between bronchiolitis and PBW. The first hypothesis considers bronchiolitis to be the first manifestation of recurrent wheezing in infants and children who are susceptible to obstructive airway disease. The second hypothesis suggests that the infection and concomitant inflammatory reaction in the acute phase leads to airway epithelium injury resulting in long-term obstructive airway disease. In line with the latter hypothesis, corticosteroids may have a beneficial effect on the prevention of post-bronchiolitic wheezing. OBJECTIVES: The objective of this review was to evaluate the effect of inhaled corticosteroids, started during the acute phase of bronchiolitis, on the prevention of post-bronchiolitic wheezing. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2006) which contains the Cochrane Acute Respiratory Infections Group's trials register, MEDLINE (1966 to September 2006), EMBASE (1980 to September 2006) and Current Contents (September 2006). Abstracts and reports of congresses (ERS 1999 to September 2005, ATS 1999 to September 2005) were obtained. We contacted experts in the field and pharmaceutical companies for ongoing or unpublished studies. SELECTION CRITERIA: Randomised placebo-controlled trials studying the effect of inhaled corticosteroids in children younger than two years of age with the clinical diagnosis of acute bronchiolitis were included. DATA COLLECTION AND ANALYSIS: Two authors independently extracted data and assessed trial quality using the Jadad 5-point scale. MAIN RESULTS: Five studies matched the inclusion criteria, with a median Jadad score of 4 (Inter Quartile Range 3 to 4), involving 374 infants. Pooling of the data was limited, due to the clinical diversity of the studies. However, no effect of inhaled corticosteroids in the prevention of wheezing (diary records or GP diagnosed), hospital re-admissions or use of corticosteroids or bronchodilators could be demonstrated. Duration of therapy, length of follow up or causative agent (respiratory syncytial virus or not) did not influence the pooled effect. In the three studies that also evaluated the adverse events, none were reported. AUTHORS' CONCLUSIONS: This review does not demonstrate an effect of inhaled corticosteroids given during the acute phase of bronchiolitis in the prevention of post-bronchiolitic wheezing. The small number of included participants and the inability to pool all clinical outcomes precludes us from making strong recommendations.


Assuntos
Corticosteroides/administração & dosagem , Bronquiolite/tratamento farmacológico , Broncodilatadores/administração & dosagem , Sons Respiratórios/efeitos dos fármacos , Doença Aguda , Administração por Inalação , Bronquiolite/complicações , Humanos , Lactente
14.
Nucleic Acids Res ; 29(14): 2950-62, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11452020

RESUMO

In kinetoplastid protozoa, mitochondrial (mt) mRNAs are post-transcriptionally edited by insertion and deletion of uridylate residues, the information being provided by guide (g)RNAs. Currently popular mechanisms for the editing process envisage a series of consecutive 'cut-and-paste' reactions, carried out by a complex RNP machinery. Here we report on the purification, cloning and functional analysis of two gRNA-binding proteins of 28.8 (gBP29) and 26.8 kDa (gBP27) from mitochondria of the insect trypanosome Crithidia fasciculata. gBP29 and gBP27 proved to be similar, Arg + Ala-rich proteins, with pI values of approximately 10.0. gBP27 has no homology to known proteins, but gBP29 is the C.fasciculata orthologue of gBP21 from Trypanosoma brucei, a gRNA-binding protein that associates with active RNA editing complexes. As measured in UV cross-linking assays, His-tagged recombinant gBP29 and gBP27 bind to radiolabelled poly(U) and synthetic gRNAs, while competition experiments suggest a role for the gRNA 3'-(U)-tail in binding to these proteins. Immunoprecipitates of mt extracts generated with antibodies against gBP29 also contained gBP27 and vice versa. The immunoprecipitates further harbored a large proportion of the cellular content of four different gRNAs and of edited and pre-edited NADH dehydrogenase subunit 7 mRNAs, but only small amounts of mt rRNAs. In addition, the bulk of gBP29 and gBP27 co-eluted with gRNAs from gel filtration columns in the high molecular weight range. Together, these results suggest that the proteins are part of a large macromolecular complex(es). We infer that gBP29 and gBP27 are components of the C.fasciculata editing machinery that may interact with gRNAs.


Assuntos
Crithidia fasciculata/genética , Proteínas de Protozoários , Proteínas de Ligação a RNA/genética , RNA/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Dados de Sequência Molecular , Testes de Precipitina , Ligação Proteica , RNA Guia de Cinetoplastídeos/metabolismo , RNA Mensageiro/metabolismo , RNA Mitocondrial , RNA de Protozoário/metabolismo , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Trypanosoma brucei brucei/genética
17.
Atherosclerosis ; 240(2): 408-14, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25897792

RESUMO

OBJECTIVE: Lomitapide (a microsomal triglyceride transfer protein inhibitor) is an adjunctive treatment for homozygous familial hypercholesterolaemia (HoFH), a rare genetic condition characterised by elevated low-density lipoprotein-cholesterol (LDL-C), and premature, severe, accelerated atherosclerosis. Standard of care for HoFH includes lipid-lowering drugs and lipoprotein apheresis. We conducted a post-hoc analysis using data from a Phase 3 study to assess whether concomitant apheresis affected the lipid-lowering efficacy of lomitapide. METHODS: Existing lipid-lowering therapy, including apheresis, was to remain stable from Week -6 to Week 26. Lomitapide dose was escalated on the basis of individual safety/tolerability from 5 mg to 60 mg a day (maximum). The primary endpoint was mean percent change in LDL-C from baseline to Week 26 (efficacy phase), after which patients remained on lomitapide through Week 78 for safety assessment and further evaluation of efficacy. During this latter period, apheresis could be adjusted. We analysed the impact of apheresis on LDL-C reductions in patients receiving lomitapide. RESULTS: Of the 29 patients that entered the efficacy phase, 18 (62%) were receiving apheresis at baseline. Twenty-three patients (13 receiving apheresis) completed the Week 26 evaluation. Of the six patients who discontinued in the first 26 weeks, five were receiving apheresis. There were no significant differences in percent change from baseline of LDL-C at Week 26 in patients treated (-48%) and not treated (-55%) with apheresis (p = 0.545). Changes in Lp(a) levels were modest and not different between groups (p = 0.436). CONCLUSION: The LDL-C lowering efficacy of lomitapide is unaffected by lipoprotein apheresis.


Assuntos
Anticolesterolemiantes/administração & dosagem , Benzimidazóis/administração & dosagem , Remoção de Componentes Sanguíneos/métodos , LDL-Colesterol/sangue , Homozigoto , Hiperlipoproteinemia Tipo II/terapia , Adulto , Anticolesterolemiantes/efeitos adversos , Benzimidazóis/efeitos adversos , Biomarcadores/sangue , Remoção de Componentes Sanguíneos/efeitos adversos , Terapia Combinada , Feminino , Predisposição Genética para Doença , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/genética , Lipoproteína(a)/sangue , Masculino , Fenótipo , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
18.
J Interferon Cytokine Res ; 17(11): 695-700, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9402107

RESUMO

Tumor cells are protected from antibody-dependent complement-mediated lysis by membrane-bound regulators of complement activation (m-RCA). m-RCA are expressed on uveal melanoma cells. We determined whether cytokine treatment affects expression of m-RCA on these cells in vitro. m-RCA expression on uveal melanoma cell lines was studied by flow cytometry, using monoclonal antibodies directed against CD46, CD55, and CD59. Cytokines studied were interferon-alpha (IFN-alpha), IFN-gamma, interleukin-1B (IL-1B), IL-12, and tumor necrosis factor-alpha (TNF-alpha). All three m-RCA were expressed on the uveal melanoma cell lines (CD59>>CD46>CD55), although in variable amounts. With a few exceptions, the cytokines had no effect on m-RCA expression. CD55 expression was not influenced by any of the cytokines. IFN-gamma downregulated expression of CD46 on one cell line (p < 0.01). TNF-alpha upregulated CD59 expression on two of the five cell lines (p < 0.012 and p < 0.001, respectively), which effect was dose dependent. IFN-alpha, IFN-gamma, IL1-beta, IL12, and TNF-alpha had limited effects on m-RCA expression on uveal melanoma cells in vitro.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas do Sistema Complemento/metabolismo , Citocinas/uso terapêutico , Melanoma/tratamento farmacológico , Proteínas de Membrana/metabolismo , Neoplasias Uveais/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Interferons/uso terapêutico , Interleucinas/uso terapêutico , Melanoma/metabolismo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/uso terapêutico , Neoplasias Uveais/metabolismo
19.
Transplantation ; 65(2): 272-5, 1998 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9458029

RESUMO

BACKGROUND: These experiments investigated the ability of the donor-specific unresponsiveness created by the intrathymic inoculation of donor alloantigen to effectively prevent chronic rejection in an established rat model of chronic renal allograft rejection. METHODS: Three study groups were examined: (1) Allograft controls--F-344 rats received a Lewis renal allograft plus 10 days of low-dose cyclosporine (CsA); (2) isograft controls--F-344 rats received an F-344 renal isograft and low-dose CsA; (3) experimental group--F-344 rats received a T-cell depleted syngeneic bone marrow transplant and intrathymic injection of Lewis bone marrow. Twenty-one days after bone marrow transplant, these animals received a Lewis renal allograft. RESULTS: Allograft controls demonstrated severe parenchymal fibrosis; isograft controls and intrathymic (IT) animals failed to develop this lesion. Immunohistochemical analysis revealed increased CD4+ T cells infiltrating the cortex of the allograft controls. Cytokine interferon-gamma and interleukin-2 transcripts were strongly positive in allograft controls and were absent from isograft controls and IT allografts as determined by reverse transcriptase-polymerase chain reaction. Analysis of tolerant grafts by flow microfluorimetry and genomic DNA amplification could not detect chimerism to a level of < 0.1%. CONCLUSION: IT inoculation of donor alloantigen can confer long-term unresponsiveness and prevent the development of the characteristic lesions of chronic rejection.


Assuntos
Transplante de Medula Óssea/imunologia , Rejeição de Enxerto/prevenção & controle , Tolerância Imunológica , Isoantígenos/farmacologia , Transplante de Rim/imunologia , Quimeras de Transplante , Animais , Injeções , Isoantígenos/administração & dosagem , Isoantígenos/uso terapêutico , Transplante de Rim/patologia , Depleção Linfocítica , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Timo , Transplante Homólogo
20.
Invest Ophthalmol Vis Sci ; 38(9): 1865-72, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9286277

RESUMO

PURPOSE: Because the expression of human leukocyte antigen (HLA) antigens is important for immunologic recognition of tumor cells, we determined expression of locus-specific HLA class I antigens in uveal melanoma and tested whether the level of HLA expression was related to prognosis or associated with known prognostic parameters. METHODS: Expression of HLA-A and -B antigens was determined on 30 formalin-fixed and paraffin-embedded sections of uveal melanoma by immunohistochemistry with locus-specific monoclonal antibodies and scored semiquantitatively. RESULTS: The level of expression of HLA-A and -B varied between uveal melanomas. Expression levels of HLA-A and -B were significantly correlated (P = 0.02). High HLA-B expression was significantly correlated with the presence of epithelioid cells (P = 0.04) in the tumor. Expression levels of HLA-A as well as of HLA-B, cell type, mitotic rate, Mib-1 score, and largest tumor diameter were significant predictive factors for survival. High expression of HLA-A and -B was associated with a decreased survival. Multiple Cox regression analysis with stepwise selection of covariates showed that the contribution of HLA-A expression to survival (P = 0.0003) exceeded that of tumor diameter (P = 0.02) and Mib-1 score (P = 0.04). CONCLUSIONS: Lack of expression of HLA-A as well as of HLA-B antigens on uveal melanoma is correlated with a better patient survival. Our data suggest that shedding of uveal melanoma micrometastases with a low expression of HLA class I into the systemic circulation may facilitate their removal and prevent the development of metastases. These findings support a protective role for natural killer cells in the development of metastatic disease in uveal melanoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Antígenos HLA-A/metabolismo , Antígenos HLA-B/metabolismo , Melanoma/metabolismo , Neoplasias Uveais/metabolismo , Adolescente , Adulto , Idoso , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias Uveais/mortalidade , Neoplasias Uveais/patologia
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