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1.
Public Health ; 185: 332-337, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32721771

RESUMO

OBJECTIVES: In 2017, one in four French 17-year-olds was a daily smoker, even though France prohibited the sale of tobacco to under-18 minors in 2009. This research aims to evaluate the retail violation rate for sale to minors (RVRms) and the associated factors. STUDY DESIGN: The study design used is observational mystery shopping study. METHODS: We conducted a mystery shopping study enlisting 12-year-old and 17-year-old youths in a representative sample of 527 tobacco outlets during three weeks in spring 2019. Multinomial Logit and Probit regressions were estimated on the data collected. RESULTS: The law is not respected. Two of three sellers (65.2%) were willing to make an illegal sale to a 17-year-old minor, and almost one in 12 (8.1%) were willing to sell to a 12-year-old child attempting to buy tobacco. Illegal sales were more likely to be made by male sellers, retailing in big cities, when there were no in-shop queues, and to 17-year-old females. The absence of the mandatory enforcement poster flagging up the ban on the sale of tobacco to minors appears to be a strong factor associated with RVRm. CONCLUSIONS: These findings show that progress needs to be made to better enforce tobacco control legislation to help decrease underage smoking in France. Rate of compliance with the law could be improved by stronger enforcement measures and tougher sanctions, but also by training and the provision of age-verification tools for sellers, as demonstrated by experiments in other countries.


Assuntos
Comércio/legislação & jurisprudência , Menores de Idade/legislação & jurisprudência , Produtos do Tabaco/legislação & jurisprudência , Adolescente , Comportamento do Adolescente , Criança , Comércio/estatística & dados numéricos , Feminino , França/epidemiologia , Humanos , Masculino , Marketing , Menores de Idade/estatística & dados numéricos , Fumar/epidemiologia , Fumar/legislação & jurisprudência , Nicotiana , Produtos do Tabaco/economia , Produtos do Tabaco/estatística & dados numéricos
2.
Z Geburtshilfe Neonatol ; 218(5): 190-4, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-25353212

RESUMO

The average age of childbearing has risen markedly in Germany and other high-income countries during the past 2 decades. Women aged 35 years or older have an increase in pregnancy complications and in preexisting medical conditions including obesity, diabetes and hypertension as well as a significant increase in the gestational age-related rate of stillbirth compared to younger mothers. Additional individual risk factors for stillbirth are primiparity, body mass index>30 and smoking. After exclusion of risk factors the absolute risk of stillbirth in women aged≥40 years old is 2-fold higher (1 in 503 maternities) at 39/40 weeks of gestation compared to women aged<35 years (1 in 1 020 maternities) at the same gestational age. Women aged 40 years or older have a similar stillbirth risk at 39 weeks of gestation to 25-29-year-olds at 41 weeks gestation. The underlying mechanism for the excess risk of stillbirth in women of advanced maternal age after exclusion of congenital anomalies is unknown. Independent of maternal age the cumulative probability of perinatal death increases from 1.8/1 000 deliveries at 38 weeks of gestation to 9.3/1 000 deliveries at 42 weeks of gestation. Whether on the basis of these data induction of labour at 39 weeks of gestation should be recommended in women of advanced maternal age has recently been discussed in a Scientific Impact Paper of the Royal College of Obstetricians and Gynaecologists. In this context it should be taken into account that the rate of Caesarean sections in women aged 40 years or over is 40%, and, in particular, older nulliparous may request elective Caesaran section rather than elective induction of labour. Recent metaanalyses have shown that elective induction of labour before or after term is not associated with an increase of the Caesarean section rate compared to expectant management. Up to now no randomised controlled trials exist and consequently no -recommendations from current guidelines regarding induction of labour in women of advanced maternal age can be given. In any case, a careful consultation and an individual risk-benefit analysis regarding the obstetric management is mandatory, and the final decision should be made in agreement between the pregnant women and the obstetrician. Currently a randomised controlled trial in the U.K. comparing induction of labour at 39 weeks of gestation with expectant management in nulliparous women aged over 35 years is recruiting, with the aim to determine intrapartum complications and perinatal morbidity and mortality in both managements.


Assuntos
Cesárea/métodos , Cesárea/estatística & dados numéricos , Trabalho de Parto Induzido/mortalidade , Trabalho de Parto Induzido/estatística & dados numéricos , Idade Materna , Natimorto/epidemiologia , Adulto , Distribuição por Idade , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
3.
Rev. chil. endocrinol. diabetes ; 7(3): 89-93, jul.2014. tab, graf
Artigo em Espanhol | LILACS | ID: lil-789303

RESUMO

The presence of insulin resistance (IR) has been indirectly assessed in Type 1 Diabetics (T1DM) through the detection of Metabolic Syndrome (MS), by applying criteria for Type 2 Diabetics(T2DM). In the EDC study (the Pittsburg Epidemiology of Diabetes Complications) a formula applicable to T1DM was validated, quantifying IR through the glucose uptake (GU) employing the usual clinical and laboratory parameters, in patients with HbA1c < 11.4 percent. Objectives: To determine in T1DM whether there exists a relationship between the presence of MS according to the Modified NCEP/ATPIII criteria and IR quantification through assessment of the glucose uptake or GU. Patients and Method: The modified NCEP/ATPIII criteria were applied to 150 T1DM patients, and those with more than 3 altered parameters were classified as MS carriers. IR was quantified through the glucose uptake (GU), applying the formula for Estimated Glucose Disposal Rate (GDR-EDC). Results: 26.6 percent of the T1DM (40 patients) complied with the modified NCEP/ATPIII criteria. When the formula for GU was applied (31 patient), 90.3 percent of the T1DM showed insulin resistance (GU value < 8.77). And when applied to 124 patients (T1DM with and without MS and HbA1c < 11,4 percent) 75 percent showed IR...


Assuntos
Humanos , Masculino , Adulto , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 1/complicações , Resistência à Insulina , Síndrome Metabólica/complicações , Estudos Transversais
4.
Oncogene ; 32(50): 5574-81, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-23995793

RESUMO

Imiquimod (IMQ), a nucleoside analogue of the imidazoquinoline family, is used in the topical treatment of basal cell carcinoma (BCC) and other skin diseases. It is reported to be a TLR7 and TLR8 agonist and, as such, initiates a Th1 immune response by activating sentinel cells in the vicinity of the tumour. BCC is a hedgehog (HH)-driven malignancy with oncogenic glioma-associated oncogene (GLI) signalling activated in a ligand-independent manner. Here we show that IMQ can also directly repress HH signalling by negatively modulating GLI activity in BCC and medulloblastoma cells. Further, we provide evidence that the repressive effect of IMQ on HH signalling is not dependent on TLR/MYD88 signalling. Our results suggest a mechanism for IMQ engaging adenosine receptors (ADORAs) to control GLI signalling. Pharmacological activation of ADORA with either an ADORA agonist or IMQ resulted in a protein kinase A (PKA)-mediated GLI phosphorylation and reduction in GLI activator levels. The activation of PKA and HH pathway target gene downregulation in response to IMQ were abrogated by ADORA inhibition. Furthermore, activated Smoothened signalling, which positively signals to GLI transcription factors, could be effectively counteracted by IMQ. These results reveal a previously unknown mode of action of IMQ in the treatment of BCC and also suggest a role for ADORAs in the regulation of oncogenic HH signalling.


Assuntos
Aminoquinolinas/farmacologia , Antineoplásicos/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Hedgehog/metabolismo , Receptores Purinérgicos P1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Linhagem Celular Tumoral , Humanos , Imiquimode , Fatores de Transcrição Kruppel-Like/metabolismo , Meduloblastoma/genética , Meduloblastoma/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Purinérgicos P1/genética , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/metabolismo , Proteína GLI1 em Dedos de Zinco , Proteína Gli3 com Dedos de Zinco
5.
Rev Epidemiol Sante Publique ; 59(3): 175-86, 2011 Jun.
Artigo em Francês | MEDLINE | ID: mdl-21530120

RESUMO

BACKGROUND: As recommended by WHO in the fight against smoking, the French authorities have decided to implement the display of 14 "shock pictures" on cigarette packages in 2011. This study examines the effectiveness of this policy. METHODS: The present study is based on a self-reported questionnaire administered to a sample of 418 first-year medical students from a private faculty in January 2010. We consider a set of 12 European visual warnings that address different smoking problems. Econometric modeling is used to study the determinants of answers. RESULTS: Our results were twofold. Firstly, the most effective symbols concern the smoker himself/herself, they are explicit and related to an advanced stage of disease. Secondly, the warnings seem to be more effective to confirm the non-smokers in their choice than to deter smokers to smoke. CONCLUSION: This tobacco control policy seems to be effective. Therefore, visual warnings have to be carefully chosen before implementation.


Assuntos
Publicidade , Abandono do Hábito de Fumar , Prevenção do Hábito de Fumar , Adolescente , Adulto , Publicidade/métodos , Feminino , França , Humanos , Masculino , Fumar/efeitos adversos , Abandono do Hábito de Fumar/métodos , Inquéritos e Questionários , Organização Mundial da Saúde
7.
Transplant Proc ; 42(9): 3444-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21094794

RESUMO

Vascular calcifications (VCs) are important predictors of cardiovascular mortality in patients with chronic kidney disease (CKD). We have shown previously that osteoprotegerin (OPG), a potential early biomarker for VC, was an independent predictor of mortality in CKD patients. The aim of our study was to follow longitudinally coronary and aortic VCs. VCs were measured using Siemens 16 detector CT in a group of predialysis and hemodialyzed patients before and after a follow-up of 4 years. Some of these patients were transplanted in the meantime. Renal function, calcium, phosphate, iPTH, hs-CRP (high sensitive protein C reactive), and OPG serum levels were also compared. VCs progressed in predialysis, hemodialyzed, and transplanted patients but the progression was not the same in all arterial beds. A progression of coronary calcifications was observed in predialysis and transplanted patients, while aortic calcifications worsened significantly only in hemodialyzed patients. OPG serum levels and hs-CRP were significantly lower among transplanted patients. We concluded that VC depends on the severity of the kidney disease. Transplanted patients are not protected from VC, yet their OPG serum levels were significantly lower, suggesting that there is no link between between OPG levels and severity of VC. Longer follow-up of these patients would be necessary to assess whether a decline in OPG correlates with better survival.


Assuntos
Doenças da Aorta/etiologia , Calcinose/etiologia , Doença da Artéria Coronariana/etiologia , Nefropatias/complicações , Osteoprotegerina/sangue , Adulto , Idoso , Doenças da Aorta/sangue , Doenças da Aorta/diagnóstico por imagem , Bélgica , Biomarcadores/sangue , Calcinose/sangue , Calcinose/diagnóstico por imagem , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Nefropatias/sangue , Nefropatias/terapia , Transplante de Rim , Análise dos Mínimos Quadrados , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Diálise Renal , Índice de Gravidade de Doença , Fatores de Tempo , Tomografia Computadorizada por Raios X
8.
Artigo em Espanhol | LILACS | ID: lil-627537

RESUMO

Objetivo: Evaluar en nuestro medio a las Periodontitis Moderadas a Severas (PM/S) en embarazadas como factores de riesgo de prematuridad (PP), ruptura prematura de membranas (RPM) y bajo peso al nacer (BPN). Método: Este estudio de cohorte, observacional y prospectivo involucró a 66 embarazadas en las semanas 24 a 30 de gestación, sin patologías sistémicas diagnosticadas, asistidas en dos hospitales universitarios de Maternidad y Neonatología de la ciudad de Córdoba, Argentina. Las pacientes fueron incorporadas al Grupo 1 ó de Cohorte expuesta al riesgo (CE) y Grupo 2 ó Cohorte no expuesta al riesgo (CNE) según presentaran o no PM/S en no menos de 4 sitios ubicados en diferentes cuadrantes de la boca. Fueron considerados los siguientes indicadores clínicos: índice de Placa Bacteriana (Pb); índice Gingival (IG); Profundidad de Sondaje (PS) y Nivel de Inserción Clínica (NIC) e"3 mm. Posteriormente, fueron recolectados los datos perinatales a partir de las historias clínicas de acuerdo con el sistema informático perinatal SIP (CLAP-OPS/OMS) y sometidos a los análisis estadísticos correspondientes. Resultados: Veintiún pacientes (n=21) conformaron el Grupo 1 ó CE; veintitrés mujeres (n=23) el Grupo 2 ó CNE y 22 embarazadas debieron ser excluidas por razones médicas. El 13.6 por ciento del total de pacientes, presentó su parto antes de las 37 semanas de gestación (PP). El Odds Ratio hallado para prematuridad fue de 6.06 (IC 95 por ciento; 5.86 - 7.76); para RPM, 2.8 (IC 95 por ciento; 1.81 - 4.39) y con respecto al BPN no se hallaron diferencias en la población estudiada. Conclusión: En la población analizada, las Periodontitis maternas moderadas a severas constituyen un verdadero factor de riesgo para PP y para RPM; por el contrario las mismas parecerían no tener influencia sobre los nacimientos de bajo peso.


Objectives: To evaluate moderate to severe Periodontitis (M/SP) in pregnant women as a risk factor for preterm birth (PTB), premature rupture of membranes (PROM) and low birth weight (LBW). Method: This observational and prospective cohort study involved 66 pregnant women between weeks 24 and 30 of gestation, without diagnosed systemic pathologies, attending at the Maternal and Neonatology University Hospital, Cordoba, Argentina. The patients were integrated into Group 1 or Cohort exposed to risk (CER) and Group 2 or Cohort not exposed to risk (CNER) according to whether they showed or not moderate to severe PD in no less than 4 points situated in different quadrants of the mouth. The following clinical indicators were considered: Dental Plaque Index (DP); Gingival index (GI); Periodontal Depth (PD) and Clinical Attachment Level (CALe"3 mm). Later, the perinatal data was collected from the medical records, according to the Perinatal informatic system, Latin American Center of Perinatology and Human Development-Panamerican Health Organization/WHO) and submitted to under proper statistical analyses. Results: Group 1 or CER comprised twenty-one patients (n=21); Group 2 or CNER comprised twenty-three women. 22 pregnant women had to be excluded due to medical reasons. 13.6 percent of the patients gave birth before the 37th week of gestation (PTB). The Odds Ratio for prematurity was 6.06 (CI 95 percent; 5.86 - 7.76); 2.8 for PROM (CI 95 percent; 1.81 - 4.39) and no differences were found concerning LBW among the population studied. Conclusion: In the population of patients studied, moderate to severe PD in pregnant women constitute a real risk factor for premature birth as well as for premature rupture of membranes; on the other hand, these diseases would not seem to affect low birth weight.


Assuntos
Recém-Nascido , Periodontite/complicações , Ruptura Prematura de Membranas Fetais/etiologia , Trabalho de Parto Prematuro/etiologia , Argentina , Estudos de Coortes , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/etiologia , Índice de Placa Dentária , Recém-Nascido de Baixo Peso , Perda da Inserção Periodontal , Índice Periodontal , Periodontite/epidemiologia , Medição de Risco
9.
Rev. méd. Chile ; 137(6): 729-736, jun. 2009. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-524951

RESUMO

Background: Patients with type 2 diabetes have a high incidence of coronary artery disease, which is even higher among those with renal failure. A serum level of cystatin C are used to assess renal function and is a potential cardiovascular risk factor. Adiponectin is an anti-atherogenic factor. Aim: To measure cystatin C and adiponectin in type 2 diabetic patients with and without coronary artery disease. Material and methods: Nine diabetic patients with coronary artery disease aged 76± 10 years, 20 diabetics without coronary artery disease aged 61 ±5 years and 20 non diabetic subjects aged 57±10 years, were studied. Results: Serum levels of cystatin C (mg/L) were 1.5 (range 0.89-219), 0.81 (range 0.71-1.08) and 0.68 mg/L (range 055-0.75) in diabetics with and without coronary artery disease and controls, respectively (p <0.0001). No differences in adiponectin between groups and no association between cystatin C and adiponectin, were observed. No association between both parameters and body mass index orglycosilated hemoglobin Ale was observed. Cystatin C had a positive correlation with serum creatinine (r =0.57p <0.001). Conclusions: Diabetics with coronary artery disease have higher levels of cystatin C, that are closely correlated with serum creatinine levels.


Assuntos
Idoso , Humanos , Pessoa de Meia-Idade , Adiponectina/sangue , Doença da Artéria Coronariana/sangue , Cistatina C/sangue , /sangue , Angiopatias Diabéticas/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Doença da Artéria Coronariana/etiologia , Fatores de Risco
10.
Clin Biochem ; 42(1-2): 108-10, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18983837

RESUMO

OBJECTIVES: Evaluation of glomerular filtration rate is of crucial importance in diabetes. Cystatin C, a cysteine protease inhibitor seems to be an interesting parameter. DESIGN AND METHODS: 67 diabetic patients with normal creatinine are evaluated. Cystatin C is compared to renal markers, by reference to Cr EDTA clearance. RESULTS: Significant correlations are found between cystatin C and creatinine (r=0.54). GFR MDRD (r=-0.47) and GFR Cr EDTA (r=-0.47). The AUC of the receiver operating curves is better for GFR MDRD (0.83) and cystatin C (0.75) than for creatinine (0.63) considering the cut off value of 80 mL/min for GFR EDTA. CONCLUSION: Cystatin C seems to be a more sensitive parameter than creatinine for the detection of an incipient nephropathy in diabetes.


Assuntos
Cistatina C/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/diagnóstico , Adulto , Idoso , Nefropatias Diabéticas/sangue , Feminino , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade
11.
Toxicol In Vitro ; 22(6): 1662-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18602460

RESUMO

Arsenic (As) has been shown to alter one or more DNA repair processes. Excision repair cross-complementing 1 and 2 (ERCC1 and ERCC2) have shown to be associated with arsenic-induced toxicity and carcinogenicity. In this study, we investigated cytotoxic effects of various As metabolites in relation to two nucleotide excision repair genes: ERCC1 and ERCC2. Various arsenate (pentavalent) and arsenite (trivalent) metabolites were tested in ERCC1, ERCC2 deficient and wild type cells. Our results showed that in the selected concentration range pentavalent As metabolites; iAs(V), MMA(V) and DMA(V) were not cytotoxic, unlike the trivalent As metabolites; iAs(III), MMA(III) and DMA(III). The measured LC(50) demonstrated a significant difference (p<0.01) for iAs(III) between the three cell lines, while MMA(III) and DMA(III) are more cytotoxic to all three cell lines. UV5 (ERCC2 deficient) cells also showed a lower resistance to iAs(III) in comparison to AA8 (wild type) and UV20 (ERCC2 deficient) cells. This might be explained through the generation of hydrogen peroxide (H(2)O(2)), which is generated by increase of intracellular Ca(2+) level. Generation of H(2)O(2) in UV5 cells after incubation with iAs(III) is significantly higher than AA8 and UV20 cells (p<0.01). In conclusion, absence of ERCC2 leads to a increased generation of H(2)O(2) by iAs(III) in UV5 cells, which is in contrast to AA8 and UV20 cells.


Assuntos
Arsenitos/toxicidade , Proteínas de Ligação a DNA/efeitos dos fármacos , Endonucleases/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Proteína Grupo D do Xeroderma Pigmentoso/efeitos dos fármacos , Animais , Arsenitos/administração & dosagem , Arsenitos/química , Células CHO , Cálcio/metabolismo , Cricetinae , Cricetulus , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/química , Humanos , Peróxido de Hidrogênio/metabolismo , Dose Letal Mediana , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo
12.
Toxicol In Vitro ; 22(3): 682-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18242949

RESUMO

In recent studies we have demonstrated that arsenic (As) metabolites change the composition of neuronal cytoskeletal proteins in vivo and in vitro. To further examine the mechanism of arsenic-induced neurotoxicity with various arsenate metabolites (iAsV, MMAV and DMAV) and arsenite metabolites (iAsIII, MMAIII and DMAIII), we investigated the role of the proteolytic enzyme calpain and its involvement in the cleavage of p35 protein to p25, and also mRNA expression levels of calpain, cyclin-dependent kinase 5 (cdk5) and glycogen synthase kinase 3 beta (gsk3ss). A HeLa cell line transfected with a p35 construct (HeLa-p35) was used as a model, since all other proteins such as calpain, CDK5 and GSK3beta are already present in HeLa cells as they are in neuronal cells. HeLa-p35 cells were incubated with various As metabolites and concentrations of 0, 10 and 30 microM for duration of 4 h. Subsequently the cells were either lysed to study their relative quantification levels of these genes or to be examined on their p35-protein expression. P35-RNA expression levels were significantly (p<0.01) increased by arsenite metabolites, while p35 protein was cleaved to p25 (and p10) after incubation with these metabolites. The cleavage of p35 is caused by calcium (Ca2+) induced activation of calpain. Inhibition of calpain activity by calpeptin prevents cleavage of p35 to p25. These results suggest that cleavage of p35 to p25 by calpain, probably As-induced Ca2+-influx, may explain the mechanism by which arsenic induces its neurotoxic effects.


Assuntos
Arsênio/toxicidade , Calpaína/toxicidade , Proteínas do Tecido Nervoso/efeitos dos fármacos , Síndromes Neurotóxicas/genética , Síndromes Neurotóxicas/metabolismo , Western Blotting , Cálcio/farmacologia , Calpaína/genética , Calpaína/metabolismo , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Primers do DNA , Dipeptídeos/farmacologia , Expressão Gênica/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Células HeLa , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
13.
Hum Exp Toxicol ; 26(10): 823-32, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18025055

RESUMO

Arsenic (As) is one of the oldest poisons known to men. Its applications throughout history are wide and varied: murder, make-up, paint and even as a pesticide. Chronic As toxicity is a global environmental health problem, affecting millions of people in the USA and Germany to Bangladesh and Taiwan. Worldwide, As is released into the environment by smelting of various metals, combustion of fossil fuels, as herbicides and fungicides in agricultural products. The drinking water in many countries, which is tapped from natural geological resources, is also contaminated as a result of the high level of As in groundwater. The environmental fate of As is contamination of surface and groundwater with a contaminant level higher than 10 particle per billion (ppb) as set by World Health Organization (WHO). Arsenic exists in both organic and inorganic species and either form can also exist in a trivalent or pentavalent oxidation state. Long-term health effects of exposure to these As metabolites are severe and highly variable: skin and lung cancer, neurological effects, hypertension and cardiovascular diseases. Neurological effects of As may develop within a few hours after ingestion, but usually are seen in 2-8 weeks after exposure. It is usually a symmetrical sensorimotor neuropathy, often resembling the Guillain-Barré syndrome. The predominant clinical features of neuropathy are paresthesias, numbness and pain, particularly in the soles of the feet. Electrophysiological studies performed on patients with As neuropathy have revealed a reduced nerve conduction velocity, typical of those seen in axonal degeneration. Most of the adverse effects of As, are caused by inactivated enzymes in the cellular energy pathway, whereby As reacts with the thiol groups of proteins and enzymes and inhibits their catalytic activity. Furthermore, As-induced neurotoxicity, like many other neurodegenerative diseases, causes changes in cytoskeletal protein composition and hyperphosphorylation. These changes may lead to disorganization of the cytoskeletal framework, which is a potential mechanism of As-induced neurotoxicity.


Assuntos
Arsênio/toxicidade , Síndromes Neurotóxicas/etiologia , Animais , Arsênio/metabolismo , Intoxicação por Arsênico/diagnóstico , Intoxicação por Arsênico/terapia , Reparo do DNA/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/metabolismo
14.
Toxicol In Vitro ; 21(6): 1104-12, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17553662

RESUMO

Neurological studies indicate that the central (CNS) and peripheral nervous system (PNS) may be affected by arsenic (As). As-exposed patients show significantly lower nerve conduction velocities (NCVs) in their peripheral nerves in comparison to healthy subjects. As may play a role in the disruption of neuroskeletal integrity, but the mechanisms by which it exerts a toxic effect on the peripheral and central nervous system are still unclear. In the present study, we examined the neurotoxic effects of various arsenic metabolites (iAs(III), iAs(V), MMA(V) and DMA(V)) on two different cell lines derived from the peripheral (ST-8814) and central (SK-N-SH) nervous system. The effects of the arsenic metabolites were examined on the relative quantification levels of the cytoskeletal genes, neurofilament-light (NEFL), neurofilament-medium (NEF3), neurofilament-heavy (NEFH) and microtubule-associated protein-tau (MAPT), using real-time PCR. Our results show that iAs(III) and iAs(V) have no significant effects on either cell lines. On the other hand, MMA(V) and DMA(V) cause significant changes in expression levels of NEF3 and NEFL genes, while the expression level of the NEFH gene is significantly increased in both cell lines.


Assuntos
Arsênio/toxicidade , Proteínas de Neurofilamentos/genética , Proteínas tau/genética , Intoxicação por Arsênico/metabolismo , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , RNA Mensageiro/metabolismo
15.
Rev. méd. Chile ; 134(3): 305-311, mar. 2006. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-426096

RESUMO

Background: Acute pyelonephritis in children can leave a kidney scar that eventually can lead to hypertension or renal failure. 99mTc-dimercaptosuccinic acid renal scintigraphy (RC DMSA) is a widely accepted technique to assess children with acute pyelonephritis. Aim: To evaluate the presence of residual kidney scars detected through RC DMSA, in children with a first episode of acute pyelonephritis. Patients and methods: Clinical records of children with a first episode of acute pyelonephritis that were assessed within seven days of the episode with RC DMSA were reviewed. Children were considered eligible if they did not have a new episode of acute pyelonephritis and a second RC DMSA, one year after the first episode, was performed. The presence or absence of a renal scar after one year was associated to demographic, scintigraphy and laboratory variables. Results: Fifty nine children, aged 1 month to 10 years, 35 females, were studied. Thirty nine percent had a renal scar in the scintigraphy perfomed after one year of follow up. The presence of a scar was correlated with a C reactive protein over 130 mg/dl and an altered relative renal function (below 44%), during the acute phase. Conclusions: A high C reactive protein and alterations of relative renal function during the acute phase of acute pyelonephritis in children, may be risk factors for the development of renal scars in the long term follow up.


Assuntos
Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Cicatriz , Rim , Pielonefrite , Compostos Radiofarmacêuticos , Doença Aguda , Biomarcadores/análise , Sedimentação Sanguínea , Proteína C-Reativa/análise , Cicatriz/etiologia , Seguimentos , Rim/patologia , Contagem de Leucócitos , Pielonefrite/complicações , Curva ROC , Fatores de Risco , Sensibilidade e Especificidade
16.
Hum Exp Toxicol ; 25(11): 667-74, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17211985

RESUMO

Exposure to arsenic compounds may lead to skin and lung cancer and various disorders such as vascular disease and peripheral neuropathy in humans. Peripheral arsenic neurotoxicity has been demonstrated clinically and in electrophysiological studies. Patients intoxicated with arsenic show neurological symptoms in their feet and hands. These patients show significantly lower nerve conduction velocities (NCVs) in their peripheral nerves in comparison with controls. The mechanism of arsenic peripheral nervous system (PNS) toxicity, however, has never been described before. This is the first study to investigate the toxicity of arsenic on the PNS. Male Wistar rats were exposed to arsenite given as a single dose i.v. After sacrifice, sciatic nerves were excised and the protein composition was analysed. Protein analysis of sciatic nerves showed disappearance of neurofilament and fibroblast proteins in rats treated with arsenite doses of 15 and 20 mg/kg in comparison with the control groups. Some fibroblast protein bands had disappeared in the 20-mg/kg dose group. The analysed neurofilament-M and -L proteins decreased dose dependency over time. arsenic affects the composition of proteins in the rat sciatic nerve, especially the neurofilaments. The reduction of signals in Western blot analysis reveals changes in cytoskeletal composition, which may well lead to neurotoxic effects in vivo.


Assuntos
Arsênio/toxicidade , Proteínas de Neurofilamentos/metabolismo , Nervo Isquiático/efeitos dos fármacos , Animais , Arsênio/farmacocinética , Fibroblastos/metabolismo , Masculino , Doenças do Sistema Nervoso Periférico/etiologia , Ratos , Ratos Wistar , Nervo Isquiático/metabolismo
17.
Medicina (B.Aires) ; 66(5): 421-426, 2006. tab
Artigo em Espanhol | LILACS | ID: lil-451709

RESUMO

La acumulación de hierro hepático asociada a mutaciones en el gen HFE de la hemocromatosis hereditaria (HH) en los pacientes con porfiria cutánea tarda (PCT) podría tener un papel en la etiología y en la expresión clínica de esta enfermedad. Se estudió la frecuencia de las mutaciones H63D y C282Y en un grupo de pacientes con PCT y se la comparó con la observada en un grupo de donantes voluntarios desangre. Los pacientes con PCT fueron catalogados como portadores de la forma hereditaria o adquirida de laenfermedad, según presentaran o no mutaciones en el gen uroporfirinógeno decarboxilasa (UROD). El 50% delos pacientes con PCT eran portadores de la forma genética de la enfermedad, porcentaje significativamentemayor que lo informado en otras series. El 23% de los donantes voluntarios de sangre eran portadores de lamutación H63D y 2.4% lo era de la mutación C282Y. Frecuencias similares a lo encontrado por otros autoresen población chilena de etnia blanca, en población argentina y española, pero significativamente más alta quelo encontrado en estudios en población aborigen araucana. Esto tiene, probablemente, relación con el predominio de ascendencia española en la población blanca chilena. La frecuencia de mutación en el gen HFE en pacientes con PCT no fue significativamente diferente que la observada en donantes voluntarios de sangre. Tampoco hubo diferencias significativas en la frecuencia de estas mutaciones entre los casos con PCT adquirida respecto de aquellos en que ésta era de origen genético. Los resultados obtenidos no permiten afirmar que exista asociación entre la PCT y la condición de portador de mutaciones del gen HFE de la hemocromatosis hereditaria


In patients with porphyria cutanea tarda (PCT), hepatic iron accumulation associated to hereditary hemochromatosis (HH) could play a role in the etiology and in the clinical expression of the disease. The H63D and C282Y mutations of the HFE gene frequency were studied in a PCT group of patients and compared with the frequency observed in a group of volunteer blood donors. PCT patients were cataloged as hereditary or acquired PCT carriers, whether or not they presented uroporphyrinogen decarboxilase gene mutations. Fifty percent of PCT patients were carriers of the disease’s genetic type. Such percentage is significantlyhigher than what other authors have previously informed. H63D and C282Y mutations were present in23% and 2.4% of the volunteer blood donors, respectively. Similar frequencies were informed by others authors in Chilean white ethnic populations, and also in Spaniard and Argentinean populations, but significantly higherthan that observed in Chile’s Araucanean aboriginal population. Probably the frequency of H63D and C283Y mutations are related to the Spaniard ascendancy dominance of Chile’s white ethnic population. The frequency of HFE gene mutations in PCT patients was not different than what was observed in volunteer blood donors.Similarly, there was no statistical difference in the frequency of these mutations among patients with acquired or genetic PCT disease. With the obtained results, it is not possible postulate an association between PCT and the hereditary hemochromatosis of HFE gene mutations carrier conditions


Assuntos
Humanos , Masculino , Feminino , Doadores de Sangue , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Mutação , Proteínas de Membrana/genética , Porfiria Cutânea Tardia/genética , Chile/etnologia , Frequência do Gene , Genótipo , Triagem de Portadores Genéticos , Hemocromatose/sangue , Sobrecarga de Ferro , Porfiria Cutânea Tardia/sangue , Uroporfirinogênio Descarboxilase/sangue , Uroporfirinogênio Descarboxilase/genética
18.
Rev. méd. Chile ; 132(1): 58-64, ene. 2004. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-359180

RESUMO

Background: Tc99m DMSA (dimercaptosuccinic acid) scintigraphy has a high sensitivity for the detection of cortical kidney damage. Aim: To evaluate the Tc99m DMSA renal scintigraphy in children with a first episode of acute pyelonephritis and its association with laboratory parameters, kidney ultrasound and vesicoureteral reflux. Patients and methods: We studied 143 children (age range 8 days, 12 years, 66 percent female) hospitalized with the clinical diagnosis of acute pyelonephritis (first episode) with a positive urine culture and a renal scintigraphy performed within seven days of diagnosis. DMSA was considered the gold standard for the detection of cortical lesions. Its results were related to the presence of fever, C-reactive protein (CRP), erythrocyte sedimentation rate (VHS), white blood count (WBC), ultrasound examination and vesicoureteral reflux. Results: Seventy nine percent of the population had an abnormal DMSA scan. There were no differences between sex, age and laboratory parameters in children with normal or abnormal DMSA scans, except for CRP (p <0.005). Ultrasound was coincident with the scan in 32 percent of patients. Eighteen percent had vesicoureteral reflux. Conclusions: There is a high proportion of abnormal DMSA scans in children with a first episode of acute pyelonephritis (Rev Méd Chile 2004; 132: 58-64).


Assuntos
Humanos , Masculino , Feminino , Criança , Testes de Função Renal/métodos , Nefropatias
20.
Rev. méd. Chile ; 131(11): 1301-1304, nov. 2003. ilus
Artigo em Espanhol | LILACS | ID: lil-358950

RESUMO

We report a 67 years old woman admitted to the hospital for the study of a cholestatic jaundice and massive hepatomegaly. On admission, the patient did not have liver failure. During hospital stay, the patient experienced a progressive deterioration of liver function and a monoclonal gammopathy was detected. An IgG Kappa myeloma was diagnosed. A fine needle liver biopsy disclosed the presence of amyloid. The patient developed acute liver failure and died three weeks after admission (Rev Méd Chile 2003; 131: 1301-04).


Assuntos
Humanos , Feminino , Idoso , Amiloidose/complicações , Falência Hepática Aguda/etiologia , Mieloma Múltiplo/complicações , Amiloidose/patologia , Biópsia por Agulha , Evolução Fatal , Imunoglobulina G , Mieloma Múltiplo/patologia , Paraproteinemias/complicações
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