RESUMO
EEC syndrome is an autosomal dominant genetic disease with incomplete penetrance characterized by ectrodactyly, ectodermal dysplasia, and cleft lip/palate; these manifestations can differently occur in the affected subjects and can also be associated with other anomalies, such as in the urogenital tract.We reported the case of a newborn with prenatal diagnosis of EEC type 3 associated with severe cardiac abnormalities (Tetralogy of Fallot), high esophageal atresia with fistula and penoscrotal hypospadias.
Assuntos
Fenda Labial , Fissura Palatina , Displasia Ectodérmica , Atresia Esofágica , Hipospadia , Tetralogia de Fallot , Humanos , Recém-Nascido , Fenda Labial/genética , Fenda Labial/diagnóstico , Fissura Palatina/genética , Fissura Palatina/complicações , Fissura Palatina/diagnóstico , Displasia Ectodérmica/diagnóstico , Displasia Ectodérmica/genética , Displasia Ectodérmica/complicações , Atresia Esofágica/diagnóstico , Atresia Esofágica/genética , Atresia Esofágica/complicações , Hipospadia/diagnóstico , Hipospadia/genética , Hipospadia/complicações , Mutação , Tetralogia de Fallot/complicações , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
Late-preterm infants (LPT) are at increased risk for long-term neurodevelopmental sequelae and iron deficiency. The aim of the study is to assess the positive effect of iron supplementation on psychomotor development in healthy LPT. We designed a randomized placebo-controlled double-blind trial dividing the newborns into two groups. Every patient was assessed using the Griffiths Mental Development Scales (GMDS)-II edition at 12-month post-conceptional age. The study was performed at the Neonatology Unit of our Hospital, in Italy. Sixty-six healthy LPT infants born between 340/7 and 366/7 weeks of gestational age were enrolled in the study. One group received martial prophylaxis from the third week of life to 6 months of post-conceptional age (2 mg/kg/day of iron pidolate), the other received placebo. Fifty-two of the enrolled infants were assessed using the GMDS at 12-month of post-conceptional age. Statistical analysis of the mean scores of the Griffiths subscales was performed. There was a difference in the mean developmental quotient (DQ) (p < 0.01) between the two groups: iron group mean DQ 121.45 ± 10.53 vs placebo group mean DQ 113.25 ± 9.70. Moreover, mean scores of the Griffiths subscales A, B, and D showed significant differences between the two groups (scale A p < 0.05, scale B p < 0.02, scale D p < 0.01, respectively).Conclusions: We recommend that all LPT neonates receive iron supplementation during the first 6 months of life in order to improve their 1-year neurodevelopmental quotient. What is Known: ⢠Late-preterm infants (LPT) are at increased risk for long-term neurodevelopmental sequelae and also for iron deficiency. ⢠Iron deficiency is an independent risk factor for adverse neurological outcomes. What is New: ⢠Healthy late-preterm who received iron supplementation during the first 6 months of life achieved better neurological outcomes at 12-month post-conceptional age than LPT who received placebo. ⢠Our study strongly supports the need for the implementation of martial prophylaxis in LPT neonates.
Assuntos
Deficiências de Ferro , Ferro , Suplementos Nutricionais , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido PrematuroRESUMO
This article focuses on the application of ESEM to study the dynamic interaction of hydrophobic and hydrophilic filler materials of interest for the cosmetic and pharmaceutical industries. The ability of ESEM to attain different thermodynamic stages was used to record real-time information of hydration and dehydration processes of those materials in the presence of water and sweat (used as a model physiological fluid). This information is of great importance to understand the behavior of a product containing those fillers as well as to identify potential processing issues related to the interaction of the filler with moisture.
Assuntos
Óxido de Alumínio/química , Microscopia Eletrônica de Transmissão e Varredura , Dióxido de Silício/química , Talco/química , Água/química , Dessecação/métodos , Interações Hidrofóbicas e Hidrofílicas , Filtros Microporos , Microscopia Eletrônica de Transmissão e Varredura/métodos , SuspensõesRESUMO
BACKGROUND: Incidence of adenocarcinoma of distal oesophagus and gastric cardia, probably arising from areas of intestinal metaplasia, has been increasing rapidly. AIMS: To define prevalence of intestinal metaplasia of distal oesophagus, oesophagogastric junction and gastric cardia and to evaluate potential associated factors, by means of a prospective multicentre study including University and teaching hospitals, and primary and tertiary care centres. PATIENTS: Each of 24 institutions involved in study enrolled 10 consecutive patients undergoing first-time routine endoscopy for dyspeptic symptoms. METHODS: Patients answered symptom questionnaires and underwent gastroscopy Three biopsies were taken from distal oesophagus, oesophago-gastric junction and gastric cardia, and were stained with haematoxylin and eosin. Specimens were also evaluated for Helicobacter pylori infection. RESULTS: A total of 240 patients (124 male, 116 female; median age 56 years, range 20-90) were enrolled in study. Intestinal metaplasia affected distal oesophagus in 5, oesophago-gastric junction in 19 and gastric cardia in 10 patients. Low-grade dysplasia was found at distal oesophagus and/or oesophago-gastric junction of 3/24 patients with intestinal metaplasia vs 2/216 without intestinal metaplasia (p<0.05). A significant association was found between symptoms and presence of intestinal metaplasia, regardless of location, and between Helicobacter pylori infection and intestinal metaplasia at oesophago-gastric junction. CONCLUSIONS: Intestinal metaplasia of distal oesophagus, oesophagogastric-junction and gastric cardia is found in a significant proportion of symptomatic patients undergoing gastroscopy and is associated with dysplasia in many cases. Although prevalence of dysplasia seems to decrease when specialized columnar epithelium is found in short segment, or even focally in oesophago-gastric junction, these small foci of intestinal metaplastic cells may represent source of most adenocarcinomas of cardia.
Assuntos
Esôfago de Barrett/epidemiologia , Cárdia , Neoplasias Esofágicas/epidemiologia , Junção Esofagogástrica , Feminino , Gastroscopia , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Neoplasias Gástricas/epidemiologiaRESUMO
The role of iron-dependent oxidative metabolism in protecting the oxidable substrates contained in mature adipocytes is still unclear. Because differentiation increases ferritin formation in several cell types, thereby leading to an accumulation of H-rich isoferritins, we investigated whether differentiation affects iron metabolism in 3T3-L1 pre-adipocytes. To this aim, we evaluated the expression of the genes coding for the H and L ferritin subunits and for cytoplasmic iron regulatory protein (IRP) during the differentiation of 3T3-L1 cells in adipocytes induced by the addition of isobutylmethylxanthine, insulin, and dexamethasone. Differentiation enhanced ferritin formation and caused overexpression of the H subunit, thus altering the H/L subunit ratio. Northern blot analysis showed increased levels of H subunit mRNA. A gel retardation assay of cytoplasmic extract from differentiated cells, using an iron-responsive element as a probe, revealed enhanced an RNA binding capacity of IRP1, which correlated with the increase of IRP1 mRNA. The observed correlation between differentiation and iron metabolism in adipocytes suggests that an accumulation of H-rich isoferritin may limit the toxicity of iron in adipose tissue, thus exerting an antioxidant function.
Assuntos
Adipócitos/citologia , Citocinas/biossíntese , Ferritinas/biossíntese , Proteínas Ferro-Enxofre/genética , Proteínas de Ligação a RNA/genética , Células 3T3 , Animais , Northern Blotting , Diferenciação Celular/genética , Eletroforese em Gel de Poliacrilamida , Proteína 1 Reguladora do Ferro , Proteínas Reguladoras de Ferro , Proteínas Ferro-Enxofre/biossíntese , Camundongos , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/biossíntese , Regulação para CimaRESUMO
We investigated the effect of oxalomalate (OMA, alpha-hydroxy-beta-oxalosuccinic acid), a competitive inhibitor of aconitase, on the RNA-binding activity of the iron-regulatory proteins (IRP1 and IRP2) that control the post-transcriptional expression of various proteins involved in iron metabolism. The RNA-binding activity of IRP was evaluated by electrophoretic mobility-shift assay of cell lysates from 3T3-L1 mouse fibroblasts, SH-SY5Y human cells and mouse livers incubated in vitro with OMA, with and without 2-mercaptoethanol (2-ME). Analogous experiments were performed in vivo by prolonged incubation (72 h) of 3T3-L1 cells with OMA, and by injecting young mice with equimolar concentrations of oxaloacetate and glyoxylate, which are the precursors of OMA synthesis. OMA remarkably decreased the binding activity of IRP1 and, when present, of IRP2, in all samples analysed. In addition, the recovery of IRP1 by 2-ME in the presence of OMA was constantly lower versus control values. These findings suggest that the severe decrease in IRP1 RNA-binding activity depends on: (i) linking of OMA to the active site of aconitase, which prevents the switch to IRP1 and explains resistance to the reducing agents, and (ii) possible interaction of OMA with some functional amino acid residues in IRP that are responsible for binding to the specific mRNA sequences involved in the regulation of iron metabolism.
Assuntos
Aconitato Hidratase/antagonistas & inibidores , Proteínas Ferro-Enxofre/metabolismo , Fígado/metabolismo , Oxalatos/farmacologia , Proteínas de Ligação a RNA/metabolismo , Células 3T3 , Animais , Citosol/enzimologia , Inibidores Enzimáticos/farmacologia , Glioxilatos/farmacologia , Humanos , Proteína 1 Reguladora do Ferro , Proteína 2 Reguladora do Ferro , Proteínas Reguladoras de Ferro , Proteínas Ferro-Enxofre/efeitos dos fármacos , Cinética , Mercaptoetanol/farmacologia , Camundongos , Ácido Oxaloacético/farmacologia , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/metabolismo , Proteínas de Ligação a RNA/efeitos dos fármacos , Células Tumorais CultivadasRESUMO
OBJECTIVES: This study sought to evaluate the relation between the pattern of neutrophil-endothelial adhesion in saphenous vein (SV) and internal mammary artery (IMA) grafts and the endothelial production of nitric oxide (NO). BACKGROUND: Autologous IMA and SV grafts (SVGs) are increasingly used as conduits for coronary bypass grafting. Previous studies have demonstrated a greater production of endothelial-derived relaxing factor (NO) from IMA than from SVGs. Because of the well known role of NO in modulating the adhesion of polymorphonuclear leukocytes to the endothelium, we studied the pattern of neutrophil adhesion to the endothelium of IMA and SVs under basal conditions and after inhibition of NO synthesis. METHODS: Segments of IMA and SVs were obtained from 20 patients undergoing coronary artery bypass graft surgery. We evaluated the adhesion of both unstimulated and activated neutrophils to the endothelial surface of IMA and SVs in both basal conditions and after inhibition of NO synthesis with Nomega-nitro-L-arginine methyl ester. RESULTS: Under basal conditions, no difference in unstimulated neutrophil adhesion to endothelium was observed between the two vessel conduits. After neutrophil activation, a significantly (p < 0.05) greater adhesion of neutrophils was observed in the SV than in the IMA. After inhibition of NO release, the adhesion of activated neutrophils increased in both vessels, and no significant difference between them was observed. The increased adhesion was attenuated by both L-arginine and sodium nitroprusside. CONCLUSIONS: The lesser neutrophil adhesion to the endothelium of the IMA is a consequence of enhanced release of NO at this level; this effect could be responsible for the better early and long-term patency of this conduit over the SVG in coronary bypass grafting.
Assuntos
Ponte de Artéria Coronária , Endotélio Vascular/fisiologia , Artéria Torácica Interna/patologia , Neutrófilos/fisiologia , Óxido Nítrico/fisiologia , Veia Safena/patologia , Adulto , Idoso , Adesão Celular , Endotélio Vascular/patologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , NG-Nitroarginina Metil Éster/farmacologia , Ativação de Neutrófilo , Neutrófilos/patologia , Óxido Nítrico/antagonistas & inibidoresRESUMO
The present study was designed to investigate relationships between urinary free pyridinolines (F-Pyr), serum osteocalcin (OC) and appendicular bone mineral density (BMD). Furthermore, possible correlations between such variables and putative risk factors for low bone density were also analysed. We were not able to find any relationships between biochemical markers of bone turnover and appendicular BMD or putative risk factors for osteoporosis at multivariate analysis. Multivariate analysis showed a significant decrease of BMD when age increases (p < 0.001), with menopause and time since menopause (p < 0.001), while number of pregnancies (p = 0.018) was associated with a higher value of BMD. Age, menopause and time since menopause were significantly associated with urinary excretion of F-Pyr. Indeed age was an inverse effect modifier of the relationship between urinary excretion of F-Pyr and time since menopause.
Assuntos
Densidade Óssea , Osso e Ossos/metabolismo , Estilo de Vida , Ensino , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas , Aminoácidos/urina , Biomarcadores/análise , Dieta , Feminino , Humanos , Itália/epidemiologia , Modelos Lineares , Menopausa/metabolismo , Pessoa de Meia-Idade , Atividade Motora , Análise Multivariada , Osteocalcina/sangue , Osteoporose/metabolismo , Osteoporose Pós-Menopausa/metabolismo , Paridade , História Reprodutiva , Fatores de Risco , Fumar , Fatores de TempoRESUMO
Pseudouridine is a modified nucleoside derived from RNA catabolism; the concentration of this nucleoside is elevated in body fluids of both tumour-bearing and human immunodeficiency virus (HIV) infected patients. We used an HPLC procedure to evaluate the serum pseudouridine concentration in patients with chronic hepatitis C in an attempt to determine whether the nucleoside serum concentration was related to the response to alpha-interferon treatment. We found that: a) pseudouridine serum concentration was increased significantly in 76% (29/39) of patients with chronic hepatitis C at the time of diagnosis and before any therapeutic treatment; b) pseudouridine excretion was higher in patients affected by chronic hepatitis C with cirrhosis; c) there was a positive correlation between response to therapy and pseudouridine serum concentration in patients undergoing treatment with alpha-interferon; d) during one year of alpha-interferon treatment, the pseudouridine serum concentration remained within the normal range in responder patients. These results indicate that serum pseudouridine might be useful as a valuable biochemical marker with which to monitor chronic hepatitis C patients treated with alpha-interferon.
Assuntos
Hepatite C/terapia , Interferon-alfa/uso terapêutico , Pseudouridina/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Doença Crônica , Monitoramento de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To verify whether carotid arterial intimal plus media thickness (IMT) is greater in non-insulin-dependent diabetes mellitus (NIDDM) subjects, known to be at high risk for atherosclerosis. Evidence is growing that IMT is increased in subjects with coronary heart disease (CHD) risk factors like hypercholesterolemia and cigarette smoking. RESEARCH DESIGN AND METHODS: Fifty-four NIDDM subjects and 54 sex- and age-matched control subjects underwent CHD risk factors assessment and echo-Doppler examination of carotid arteries. IMT was measured by computer technique in the common carotid artery (CCA). Presence of plaques and/or stenosis (carotid atherosclerosis [CA]) was also evaluated by a single-blinded reader. RESULTS: NIDDM subjects had larger IMT, higher levels of triglycerides, and lower concentrations of high-density lipoprotein (HDL) cholesterol compared with control subjects. IMT was positively correlated to age and systolic blood pressure and inversely to HDL cholesterol in both groups. The prevalence of CA was 46% in NIDDM subjects and 18% in control subjects. In multiple regression analysis, IMT was the only variable significantly associated to CA. CONCLUSIONS: IMT of CCA is enlarged in NIDDM subjects compared with control subjects. Its association with carotid plaques and/or stenosis might be of importance to detect early atherosclerotic lesions in the carotid arteries.
Assuntos
Artérias Carótidas/diagnóstico por imagem , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Angiopatias Diabéticas/diagnóstico por imagem , Arteriosclerose/sangue , Arteriosclerose/diagnóstico por imagem , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico por imagem , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Ultrassonografia DopplerRESUMO
One hundred and thirty-eight male subjects working as civil servants in the Catanzaro city hall, aged over 45, underwent Echo-Doppler examination of carotid and femoral arteries. Forty-one subjects (30%) presented evidence of early atherosclerotic lesions in at least 1 of the 10 examined arteries. Age, systolic blood pressure, serum triglycerides and serum glucose were higher in this group when compared with subjects without evidence of extracoronary atherosclerosis (EA), while HDL cholesterol and apolipoprotein A-I were lower. After adjustment for age, only serum triglycerides and apolipoprotein A-I levels remained significantly different. Only 21 subjects had no major coronary heart disease (CHD) risk factors, 46 had one, 47 two and 24 more than two risk factors. The prevalence of lesions was significantly higher in individuals with total cholesterol/HDL cholesterol ratio greater than 5. The presence of smoking and hypertension was almost equally represented in individuals with or without lesions. Serum triglycerides, total cholesterol/HDL cholesterol > 5 and apolipoprotein A-I seem to play a fundamental role in the development of EA, as detected by Duplex examination of carotid and femoral arteries. Age is also closely related to the presence of lesions, probably reflecting the exposure duration to CHD risk factors.
Assuntos
Arteriosclerose/complicações , Doença das Coronárias/complicações , Arteriosclerose/diagnóstico por imagem , Arteriosclerose/epidemiologia , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Doença das Coronárias/epidemiologia , Artéria Femoral/diagnóstico por imagem , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , UltrassonografiaRESUMO
Peripheral vascular diseases, both symptomatic and asymptomatic, are strong predictors of total and cardiovascular mortality. The commonly used Rose questionnaire, although highly specific, has a low sensitivity to detecting peripheral vascular disease and is not adequate for asymptomatic subjects. Doppler ultrasound measurement of the ankle/brachial systolic blood pressure ratio is a non-invasive, reproducible and accurate method of assessment of peripheral vascular disease and has been validated by angiography. METHODS. Five hundred and ten subjects, corresponding to fifty percent of the people working as civil servants in the Catanzaro city hall, were invited to join the study by a letter. Three hundred and eighty four participated. Exclusion criterion was claudicatio intermittens as detected by Rose questionnaire. All the subjects filled a questionnaire to assess coronary heart disease risk factors and underwent a full clinical examination. Brachial blood pressure was measured on both arms with participants in supine position, just before ECG. The systolic ankle blood pressure was measured with ultrasonic technique. The blood pressure cuff was placed just proximal to the medial malleolus. The ankle-brachial systolic pressure index (Winsor Index) was determined by dividing the highest of the posterior tibial or dorsalis pedis pressures by the highest brachial pressure. A limit of 0.95 was chosen to identify subjects with peripheral arterial disease. Venous blood for serum cholesterol and triglycerides, apolipoprotein AI and B and blood glucose, was collected after an overnight fasting, into Vacutainer Tubes (Becton & Dickinson). RESULTS. No subject had claudicatio intermittens. Sixteen subjects were excluded from the statistical analysis because of missing data. Two hundred and sixty-three were males and 105 females. Twenty-one (5.7%) out of 368 participants had a Winsor Index < 0.95 in at least one leg. These subjects had higher values of systolic and diastolic blood pressure compared to normal subjects whereas no differences were observed with regard to age, BMI, lipid profile and blood glucose. Furthermore the prevalence of hypertension was higher in the group of subjects with asymptomatic peripheral arterial disease. The prevalence of other risk factors for atherosclerosis (cigarette smoking, hyperlipidemia, diabetes mellitus, obesity) was similar in subjects with or without peripheral arterial disease. DISCUSSION. In the present study the prevalence of Winsor Index < 0.95 was 5.7%, similar to that reported by other authors. Hypertension was the only risk factor for atherosclerosis associated with peripheral arterial disease. Other authors also reported a higher prevalence of cigarette smoking among subjects with peripheral disease. In our population this association was not found but the participants were younger and consequently the exposure to this risk factor was shorter. CONCLUSION. The measurement of systolic ankle blood pressure by Doppler ultrasounds is a non-invasive, well accepted, highly specific and sensitive method to detect asymptomatic peripheral arterial disease. It might be of value in better defining the cardiovascular risk profile both in epidemiologic studies and clinical practice, especially in subjects with hypertension.
Assuntos
Doenças Cardiovasculares/epidemiologia , Doenças Vasculares Periféricas/epidemiologia , Adulto , Idoso , Tornozelo/irrigação sanguínea , Tornozelo/diagnóstico por imagem , Determinação da Pressão Arterial/métodos , Doenças Cardiovasculares/mortalidade , Feminino , Humanos , Hipertensão/complicações , Itália/epidemiologia , Perna (Membro)/irrigação sanguínea , Perna (Membro)/diagnóstico por imagem , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/diagnóstico por imagem , Prevalência , Prognóstico , Fatores de Risco , Inquéritos e Questionários , UltrassonografiaRESUMO
Carcinoma with pseudosarcomatous stroma of the bladder. Case report. We report a case of transitional cells carcinoma of urinary bladder with pseudosarcomatous stroma in a 54 years old male. The patient was admitted in hospital owing to recidivous haematuria events for about 3 months. Three urine samples were sent for cytological studies that showed the presence of transitional neoplastic cells. Subjected to a cystoscopic examination the patient revealed a roundish peduncled bladder formation of about 3.5 cm. in size. Hence three bladder lesion biopsies were done. The histological sections obtained pointed out the existence of two cellular populations: the first one presented roundish or lengthened, pluristratified cells arranged in solid nests, with transitional morfology and high atypias; the other population had sarcomatoid features characterized by lenghtened cells with hyperchromic nuclei. The two populations were mixed up and there were sometimes carcinomatous areas that merged into sarcomatoid areas. Chondroid areas were also observed. We diagnosed a G3 transitional cells carcinoma with pseudosarcomatous stroma. The lesion, after literature review, results to be somewhat rare and not easily interpretable since it may be confused with carcinosarcoma. The rarity of this case and the problems of differential diagnosis connected with it urged us to this pubblication along with a short review of literature.
Assuntos
Carcinoma de Células de Transição/patologia , Carcinossarcoma/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Biópsia , Carcinoma de Células de Transição/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Bexiga Urinária/diagnósticoRESUMO
Pseudouridine is a modified nucleoside derived from the degradation of some species of RNA, primarily transfer RNA, the level of which is elevated in biological fluids of tumor-bearing subjects. In order to study the relationship between pseudouridine levels and the development and progression of neoplasia, we have measured pseudouridine levels in the serum of inbred mice with high (AKR) and low (BALB/c) incidence of spontaneous lymphoma and in mice carrying transplantable lymphoid tumors. Our results show that the serum level of pseudouridine: (a) in healthy mice, is higher in females than in males; (b) increases significantly in female AKR mice in the period preceding the development of lymphoma (preneoplastic period occurring at about 6 months of age); and (c) is highest in AKR mice with lymphoma, the most elevated levels being found in mice with widely disseminated disease. The latter observation was confirmed by experiments with a transplantable AKR lymphoma (T2), where a positive correlation between tumor burden and serum pseudouridine levels was found. On the contrary, in BALB/c mice carrying a transplantable myeloma tumor (MOPC-460), no increase was seen despite the presence of a considerable tumor burden. The increase of pseudouridine in the preneoplastic period, in the absence of overt disease is viewed as an early sign of the development of the disease.
Assuntos
Linfoma/fisiopatologia , Plasmocitoma/fisiopatologia , Pseudouridina/sangue , Uridina/análogos & derivados , Animais , Técnicas de Laboratório Clínico , Feminino , Masculino , Camundongos , Camundongos Endogâmicos AKR , Camundongos Endogâmicos BALB C , Lesões Pré-Cancerosas/fisiopatologia , Especificidade da EspécieRESUMO
A specific, sensitive, and rapid method to measure pseudouridine in human blood serum is described. The method is based on the following steps: (i) deproteinization of serum samples by filtration on membrane cones or by acetonitrile; (ii) purification of nucleosides and concentration of the sample by affinity chromatography on phenylboronate gel followed by lyophilization; and (iii) separation of nucleosides and their quantitation by reverse-phase high-performance liquid chromatography. The pseudouridine mean value in 30 normal subjects was 2.52 +/- 0.28 nmol/ml. The procedure also allows the identification of inosine, uridine, guanosine, and adenosine. Nevertheless, the presence in human blood serum of enzymatic activities which convert adenosine to inosine and cytidine to uridine prevents the precise quantitation of these nucleosides. All the compounds were identified by comparing their retention times and absorbance ratios (A280/A254) with those of pure compounds, as well as by cochromatography.
Assuntos
Nucleosídeos/sangue , Pseudouridina/sangue , Uridina/análogos & derivados , Cromatografia Líquida de Alta Pressão , Humanos , Neoplasias/sangueRESUMO
A new method to measure pseudouridine (psi rd) in blood serum has been used to study patients with cancer of breast, lung, colon, and ovaries, and patients with hepatomas, non-Hodgkin lymphomas, and acute lymphoblastic leukemias, at different stages. The results indicate: (1) a significant (p less than 0.01) difference between the psi rd serum level of the cancer patient group and the normal control group; (2) that the increase of the level of serum psi rd is correlated both to the stage of the disease and to the spreading of the tumor tissue; (3) a correlation between the response to therapy and the behaviour of psi rd serum levels.
Assuntos
Neoplasias/sangue , Pseudouridina/sangue , Uridina/análogos & derivados , Neoplasias da Mama/sangue , Carcinoma Hepatocelular/sangue , Cromatografia Líquida de Alta Pressão , Neoplasias do Colo/sangue , Feminino , Humanos , Leucemia Linfoide/sangue , Neoplasias Hepáticas/sangue , Neoplasias Pulmonares/sangue , Linfoma/sangue , Neoplasias Ovarianas/sangueRESUMO
The tRNA modifying enzyme, S-adenosylmethionine:tRNA(guanine-7-)-methyltransferase, has been extensively purified from Salmonella typhimurium. A rapid and efficient purification method using phosphocellulose chromatography followed by ammonium sulfate precipitation and Sephadex G-100 gel filtration is described. The enzyme appears to be a single polypeptide chain with a molecular weight of approximately 25 000--30 000 daltons. The Km for S-adenosylmethionine and for undermethylated tRNA is 53 microM and 3.4 microM, respectively. The methylation reaction is dependent on added monovalent or divalent cations; 5 mM spermidine, 3 mM MgCl2 and 1 mM spermine are the most effective. The enzyme, though not homogeneous, is free from contaminating ribonucleases and other tRNA methyltransferases.
Assuntos
Salmonella typhimurium/enzimologia , tRNA Metiltransferases/isolamento & purificação , Cromatografia em Gel , Cinética , Magnésio/metabolismo , Cloreto de Magnésio , Peso Molecular , RNA de Transferência/metabolismo , S-Adenosilmetionina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo , tRNA Metiltransferases/metabolismoRESUMO
The catabolism of nucleic acids, particularly tRNA, produces a variety of modified nucleosides which are not reutilized by mammalian cells. Investigation of these compounds in body fluids, mainly urine, has recently provided evidence of altered metabolic situations in tumor-bearing patients. The factors involved in the alterations of modified nucleosides formation are connected with altered tRNA-modifying enzymes and/or altered turnover of subpopulations of tRNA. A common pattern in tumor cells or tissues is the presence of isoaccepting tRNA species containing aberrant nucleoside modifications. Several modified nucleosides have been detected and quantitated by HPLC analysis of the urine of normal subjects and cancer patients. Results obtained, in the authors' laboratory, among others, indicate a possible correlation between urinary excretion of these compounds and the course of the disease, with implications for the follow-up of therapeutic treatment. Particular reference should be made to psi, which appears to be a suitable marker for monitoring these subjects. The data from the authors' laboratory also show that the analysis of modified nucleosides in blood may be considered a useful tool in the search for proper markers associated with the cancer status. In this respect psi is suggested as a biochemical indicator for cancer patients.
Assuntos
Linfoma/urina , Neoplasias/metabolismo , Nucleosídeos/análise , RNA de Transferência/metabolismo , tRNA Metiltransferases/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Doença de Hodgkin/urina , Humanos , Neoplasias/enzimologia , Nucleosídeos/sangue , Nucleosídeos/urina , Valores de ReferênciaAssuntos
Doença de Crohn/diagnóstico , Hormônio Adrenocorticotrópico/administração & dosagem , Adulto , Azatioprina/administração & dosagem , Betametasona/administração & dosagem , Doença de Crohn/tratamento farmacológico , Doença de Crohn/cirurgia , Diagnóstico Diferencial , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sulfassalazina/administração & dosagemRESUMO
A fast method for a single-step fractionation of a number of tRNA methyltransferases from Salmonella typhimurium is described. The method basically consists of ion-exchange chromatography on a phosphocellulose column and permits the separation of the enzymes forming mt6A, m1G, m5U, m7G. The enzyme fractions appear sufficiently purified to allow the estimation of some molecular and kinetic properties. The apparent KM for adenosylmethionine range between 1.5 to 3.2 X 10(-5) M, whereas KM for undermethylated tRNA range between 3.1 X 10(-5) M to 3.1 X 10(-4) M. Glycerol gradient determination indicates the following Mr for the native proteins: 25 X 10(3), 40 X 10(3), 50 X 10(3) and 65 X 10(3) for m7G-, mt6A-, m1G- and m5U-forming enzymes, respectively. A complete analysis of methylated nucleosides formed in vivo in S. typhimurium has been obtained: it also allowed us to infer the pattern of the various tRNA methyltransferases for this prokaryote. The tRNA methyltransferase forming mt6A has been isolated for the first time from any type of cell.