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1.
Environ Sci Pollut Res Int ; 22(21): 16803-13, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26099597

RESUMO

This work compared the toxicity of ZnO nanoparticles (ZnO-NPs), ZnO bulk, and ZnCl2 on microbial activity (C and N transformations and dehydrogenase and phosphatase activities) and their uptake and toxic effects (emergence, root elongation, and shoot growth) on three plant species namely wheat, radish, and vetch in a natural soil at 1000 mg Zn kg(-1). Additionally, plants were also tested at 250 mg Zn kg(-1). The effects of the chemical species on Zn extractability in soil were studied by performing single and sequential extractions. ZnCl2-1000 presented the highest toxicity for both taxonomic groups. For microorganisms, ZnO-NPs demonstrated adverse effects on all measured parameters, except on N transformations. The effects of both ZnO forms were similar. For plants, ZnO-NPs affected the growth of more plant species than ZnO bulk, although the effects were small in all cases. Regarding accumulation, the total Zn amounts were higher in plants exposed to ZnO-NP than those exposed to ZnO bulk, except for vetch shoots. The soil sequential extraction revealed that the Zn concentration in the most labile forms (water soluble (WS) and exchangeable (EX)) was similar in soil treated with ZnO (NP and bulk) and lower than that of ZnCl2-treated soil, indicating the higher availability of the ionic forms. The strong correlations obtained between WS-Zn fraction and the Zn concentrations in the roots, shoots, and the effects on shoot weight show the suitability of this soil extraction method for predicting bioavailable Zn soil for the three plant species when it was added as ZnO-NPs, ZnO bulk, or ZnCl2. In this work, the hazard associated with the ZnO-NPs was similar to ZnO bulk in most cases.


Assuntos
Cloretos/química , Cloretos/toxicidade , Magnoliopsida/efeitos dos fármacos , Microbiologia do Solo , Solo/química , Compostos de Zinco/química , Compostos de Zinco/toxicidade , Óxido de Zinco/química , Óxido de Zinco/toxicidade , Cloretos/metabolismo , Ecotoxicologia , Nanopartículas/toxicidade , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Água/química , Compostos de Zinco/metabolismo , Óxido de Zinco/metabolismo
2.
Arch Environ Contam Toxicol ; 67(4): 465-73, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24793192

RESUMO

The present study assessed the uptake and toxicity of ZnO nanoparticles (NPs), ZnO bulk, and ZnCl2 salt in earthworms in spiked agricultural soils. In addition, the toxicity of aqueous extracts to Daphnia magna and Chlorella vulgaris was analyzed to determine the risk of these soils to the aquatic compartment. We then investigated the distribution of Zn in soil fractions to interpret the nature of toxicity. Neither mortality nor differences in earthworm body weight were observed compared with the control. The most sensitive end point was reproduction. ZnCl2 was notably toxic in eliminating the production of cocoons. The effects induced by ZnO-NPs and bulk ZnO on fecundity were similar and lower than those of the salt. In contrast to ZnO bulk, ZnO-NPs adversely affected fertility. The internal concentrations of Zn in earthworms in the NP group were greater than those in the salt and bulk groups, although bioconcentration factors were consistently <1. No relationship was found between toxicity and internal Zn amounts in earthworms. The results from the sequential extraction of soil showed that ZnCl2 displayed the highest availability compared with both ZnO. Zn distribution was consistent with the greatest toxicity showed by the salt but not with Zn body concentrations. The soil extracts from both ZnO-NPs and bulk ZnO did not show effects on aquatic organisms (Daphnia and algae) after short-term exposure. However, ZnCl2 extracts (total and 0.45-µm filtered) were toxic to Daphnia.


Assuntos
Cloretos/toxicidade , Nanopartículas Metálicas/toxicidade , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/toxicidade , Compostos de Zinco/toxicidade , Óxido de Zinco/toxicidade , Animais , Organismos Aquáticos , Daphnia , Oligoquetos
3.
An Sist Sanit Navar ; 37(3): 339-48, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-25567388

RESUMO

BACKGROUND: To describe the treatment of prostate cancer patients according to life expectancy, risk and comorbidity, to examine the degree to which Clinical Practice Guidelines (CPG) are followed, and to register secondary effects after one year. METHODS: Retrospective study of patients diagnosed with prostate cancer in a hospital in 2011. Socio-demographic variables, as well as comorbidity (Charlson index), tumor characteristics, treatments and secondary effects were collected. A bivariate analysis was performed using the Chi square test. RESULTS: One hundred and fourteen patients were identified. Life expectancy was higher than 10 years in 92.1%; 50% had low comorbidity, 36% medium and 14% high. Surgery was performed in 56.2%, more often in patients with intermediate-risk and low comorbidity; radiotherapy in 13.2%, more often in patients with high-risk and low comorbidity; hormonal therapy in 21.9%, more often in patients with medium comorbidity, and deferred treatment in 12.3%. CPG recommendations were not followed in 38.6%, especially in high-risk patients, 58.1%. Regarding adverse effects, 70% of patients treated with surgery presented urinary incontinence, and 48.3% erectile dysfunction. On the other hand, 17.15% of patients treated with hormonal therapy presented a cardiovascular disease, and 32.5% worsening of a cardiovascular risk factor. CONCLUSIONS: Treatment of prostate cancer takes into account risk and comorbidity, but there could be improvement in following CPG guidelines, especially in elderly patients. It is advisable to develop preventive strategies to avoid cardiovascular effects in patients with hormonal therapy.


Assuntos
Expectativa de Vida , Neoplasias da Próstata/complicações , Neoplasias da Próstata/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
J Agric Food Chem ; 55(17): 7084-92, 2007 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-17663567

RESUMO

The objective of this study was to compare the mobility, leaching, availability, and relative effectiveness of Zn from Zn-polyhydroxyphenylcarboxilate (Zn-PHP), Zn-HEDTA (Zn-N-2-hydroxyethyl-ethylenediaminetriacetate), Zn-EDDHSA [Zn-ethylenediamine-di-(2-hydroxy-5-sulfophenylacetate)], Zn-EDTA (Zn-ethylenediaminetetraacetate), Zn-S,S-EDDS (Zn-ethylenediaminedisuccinate), and Zn-EDTA-HEDTA sources by applying different Zn rates (5 and 10 mg kg(-1)) to a calcareous soil under greenhouse conditions. A lysimeter experiment was carried out for 60 days and using navy bean (Phaseolus vulgaris L.) as an indicator plant. The Zn available to the plant and easily leachable Zn were determined in soil by different single extractions, while the distribution of Zn in the soil was assessed by sequential speciation. The utilization of applied Zn by the navy bean was greatest when the Zn treatments were Zn-EDTA, Zn-EDTA-HEDTA, Zn-HEDTA, and Zn-EDDHSA. Both total Zn in the plants and soluble Zn in the plant dry matter (extracted with 1 mM 2-morpholino-ethanesulfonic acid) were positive and significantly correlated with the following: the amounts of Zn extracted with the three single extractions used to estimate soil available Zn and the amounts of Zn in the water soluble plus exchangeable and organically complexed fractions. The Zn-HEDTA, Zn-EDDHSA, Zn-EDTA-HEDTA, Zn-S,S-EDDS, and Zn-EDTA sources significantly increased the mobility of micronutrients through the soil with respect to the control and Zn-PHP source. The maximum Zn concentration obtained in the leachate fractions was 65 mg L(-1) (13% of Zn applied) for the Zn-S,S-EDDS chelate applied at a rate of 10 mg Zn kg(-1) soil. In the course of the crop, the soil pH + pe parameter increased significantly with experimental time.


Assuntos
Fertilizantes/análise , Phaseolus/crescimento & desenvolvimento , Solo/análise , Zinco/administração & dosagem , Alimentos Orgânicos , Phaseolus/metabolismo , Zinco/análise , Zinco/metabolismo
5.
Gastroenterol Hepatol ; 29(8): 437-42, 2006 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-17020675

RESUMO

INTRODUCTION: Identification of patients with hereditary nonpolyposis colorectal cancer (HNPCC) can allow colorectal cancer (CRC) prevention through colonoscopy and polypectomies. The purpose of this study was to report the clinical characteristics of HNPCC families in our registry. PATIENTS AND METHOD: HNPCC was identified using the Amsterdam criteria. Familial clustering of CRC and extracolonic cancers were investigated in families. Individuals at risk were offered annual colonoscopy, starting from the age of 25 years. RESULTS: Twelve HNPCC families were identified. There were 46 cases of CRC in 38 patients. The mean age at diagnosis of CRC was 45.4 +/- 12.7 years (range 25-73 years). In patients with documented disease, right-sided tumors predominated. Eleven patients with extracolonic cancer were identified (six tumors located in the endometrium). Of 43 at-risk individuals, 29 accepted surveillance. CONCLUSIONS: Our data confirm the importance of the family history in identifying HNPCC. This study confirms previously described characteristics in HNPCC, namely, early age at onset of CRC, right-sided predominance, multiple synchronous and metachronous neoplasms, and increased extracolonic cancers. This is the first study of clinical data in a Spanish HNPCC registry.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Adulto , Distribuição por Idade , Idoso , Feminino , Hospitais/estatística & dados numéricos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Espanha/epidemiologia
7.
Aliment Pharmacol Ther ; 24 Suppl 3: 56-63, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16961747

RESUMO

Different societies have published guidelines for colorectal cancer (CRC) surveillance in ulcerative colitis (UC). While it would seem that most gastroenterologists and endoscopists agree with these guidelines, different studies have shown that in clinical practice, the concept of dysplasia is not fully understood, and therefore, the guidelines are not always followed. According to some studies, the reason why gastroenterologists do not follow the recommendations is inadequate education. The main advance in recent years in this subject is in endoscopic diagnosis of dysplasia. The magnification and chromoendoscopy allow targeted biopsies to be taken. Some studies indicate that nontargeted biopsies are not useful in ruling out dysplasia. It is also important to realize that most dysplasia is visible in conventional colonoscopy. In colonoscopy, it is not only significant to detect dysplasia-associated lesions or masses; the endoscopist should also be trained to detect, in the course of conventional exploration, subtle changes in colour or in mucosal surfaces that imply dysplasia. Adherence to guidelines had been extensively assessed in other disease conditions (asthma, hypertension, etc.). According to our knowledge there are no such data regarding CRC surveillance in UC. Some barriers that may affect physicians include: (i) knowledge (lack of awareness or lack of familiarity); (ii) attitudes (lack of agreement, lack of self-efficacy, lack of outcome expectancy, or the inertia of previous practice) and (iii) behaviour (external barriers). In conclusion, we need new guidelines for CRC surveillance in UC, which must take into account the advances in risk factors of dysplasia and new technologies to study colon dysplasia.


Assuntos
Colite Ulcerativa/complicações , Colonoscopia/métodos , Neoplasias Colorretais/etiologia , Guias de Prática Clínica como Assunto/normas , Competência Clínica/normas , Neoplasias Colorretais/diagnóstico , Educação de Pós-Graduação em Medicina , Gastroenterologia/educação , Gastroenterologia/normas , Humanos , Fatores de Risco
10.
Clin Genet ; 69(2): 155-62, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16433696

RESUMO

The frequencies of C282Y and H63D mutations of the HFE gene vary between different populations. A previous study showed an unexpectedly high H63D frequency in Chuetas (a population of Jewish descent). The present study addressed the question of the distribution of these mutations in Jewish populations from different origins and studied the possible causes of the high H63D frequency in Chuetas. Moreover, to improve the understanding of the controversial relationship between H63D homozygosity and iron overload, a group of patients with altered iron metabolism were studied. The high frequency of H63D mutation in Chuetas is not due to a high prevalence of this mutation in Sephardic Jews. Jewish populations have low C282Y and moderate H63D frequencies, suggesting slight gene flow from their surrounding populations. In accordance with historical and demographic data, genetic drift is the most probable cause for the singular H63D frequency in Chuetas. Clinically, this study of H63D homozygotes supports the conclusion that this genotype must be taken into account, because it confers an increased risk of iron overload and therefore genetic susceptibility to developing hereditary hemochromatosis or to aggravating other diseases.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Homozigoto , Judeus/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto/genética , Alelos , Feminino , Frequência do Gene , Hemocromatose/genética , Proteína da Hemocromatose , Humanos , Masculino
13.
Aliment Pharmacol Ther ; 20(11-12): 1347-52, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15606397

RESUMO

BACKGROUND: Uncontrolled studies suggest that granulocyteaphaeresis might be useful in the management of active ulcerative colitis. AIM: To assess the efficacy of granulocyteaphaeresis treatment in active steroid-dependent inflammatory bowel disease. METHODS: We conducted a multicentre, prospective, open, pilot study in patients with steroid-dependent inflammatory bowel disease. All patients were started on 60 mg/day of prednisone; after 1 week, a five-session programme of granulocyteaphaeresis (once per week) was started. The steroid dose was tapered weekly if there was clinical improvement. Remission was defined as an inactive clinical activity index together with complete withdrawal of steroids at week 6. The patients were followed up for at least 6 months or until disease relapse. RESULTS: Twenty-six patients (14 ulcerative colitis, 12 Crohn's disease) were included. More than a half had been previously treated with immunomodulators. Remission was achieved in 62 and 70% of ulcerative colitis and Crohn's disease, respectively. During a median follow-up of 12.6 months, six of eight ulcerative colitis patients maintained their clinical remission; however, only one Crohn's disease patient remained in remission after the first 6 months of follow-up. CONCLUSIONS: Granulocyteaphaeresis is a safe treatment option in inflammatory bowel disease. A five-session programme of granulocyteaphaeresis seems to be efficient in the treatment of steroid-dependent ulcerative colitis, but not in Crohn's disease.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/terapia , Doença de Crohn/terapia , Granulócitos , Leucaférese/métodos , Prednisolona/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Indução de Remissão
15.
Gastroenterol Hepatol ; 26(8): 469-74, 2003 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-14534018

RESUMO

BACKGROUND: The role of lactose malabsorption in ulcerative colitis is controversial. The aim of this study was to compare the prevalence of lactose malabsorption in a group of ulcerative colitis patients and a control group and to modify lactose consumption in view of the results. METHODS: Lactose malabsorption was studied using the hydrogen breath test in 52 patients with ulcerative colitis and 34 controls after ingestion of 25 g of lactose. A questionnaire on ingestion of milk products was also administered. RESULTS: Of the 52 patients with ulcerative colitis, 13 (25%) presented lactose malabsorption compared with 11 of the 34 (32%) controls (p = 0.45). Twenty-four patients (46%) had been advised to completely eliminate lactose from their diets. Twenty-seven of the 39 patients without malabsorption had reduced or eliminated lactose consumption after being diagnosed with ulcerative colitis. CONCLUSIONS: No significant differences in the prevalence of lactose malabsorption was found between patients with ulcerative colitis and controls. We believe that systematic elimination of lactose from the diets of these patients is erroneous. In our environment, we recommend the hydrogen breath test only in patients with symptoms of lactose intolerance.


Assuntos
Colite Ulcerativa/complicações , Intolerância à Lactose/complicações , Adolescente , Adulto , Idoso , Testes Respiratórios , Estudos de Casos e Controles , Feminino , Humanos , Intolerância à Lactose/diagnóstico , Intolerância à Lactose/terapia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
17.
Gastroenterol Hepatol ; 26(1): 29-33, 2003 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-12525326
18.
J Clin Apher ; 17(2): 88-92, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12210712

RESUMO

The current treatment of hereditary hemochromatosis (HH) consists of performing periodic manual whole blood phlebotomies. Erythroapheresis (EPH) is considered to be an alternative procedure if the classic treatment is contra-indicated. A prospective study of 13 consecutive cases of HH were included in a periodic EPH program with the aim of assessing the efficacy, feasibility, and tolerability of EPH in the treatment of HH by induction and maintenance. Iron depletion (ferritin <20 microg/l) was achieved in all patients after a mean of 6.7 +/- 2.9 months of treatment and a mean of 13.5 +/- 7.2 EPH sessions. The procedure was well tolerated and there were no complications. After a follow-up period of 10.5 +/- 6.6 months, only four patients have required further maintenance sessions beyond 6 months after completing the induction therapy. The efficacy, speed, tolerability, and more favorable schedule of an EPH program facilitate treatment of HH.


Assuntos
Remoção de Componentes Sanguíneos , Hemocromatose/terapia , Ferro/sangue , Adulto , Transfusão de Eritrócitos , Estudos de Viabilidade , Feminino , Ferritinas/sangue , Seguimentos , Hemocromatose/complicações , Hemocromatose/congênito , Humanos , Masculino , Pessoa de Meia-Idade , Flebotomia , Estudos Prospectivos , Indução de Remissão , Resultado do Tratamento
20.
Gastroenterol Hepatol ; 25(7): 448-51, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12139838

RESUMO

We present the results of a retrospective study of endoscopic management (with flexible endoscopy) in 501 patients admitted for suspected ingestion of a foreign body between 1977 and 1997. The mean age of the patients was 55.73 19.38. Foreign bodies were found in the esophagus in 322 patients (64.3%) and endoscopic removal was successful in 307 (95.35%). More experienced endoscopists, with more than 45 cases, had a higher success rate (98.1%) than did less experienced endoscopists (87.9%) (p < 0.01). The most frequent type of foreign body in our series was meat bolus (32.8%). Underlying disease was found in 38.9%, and peptic stenosis was the most frequent. The only severe complication found was esophageal perforation in one patient (0.3%). Emergency flexible endoscopy is the most effective method for managing patients admitted for suspected ingestion of a foreign body and for the removal of foreign bodies located in the esophagus.


Assuntos
Esôfago , Corpos Estranhos/terapia , Adulto , Idoso , Esofagoscopia , Feminino , Corpos Estranhos/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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