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1.
Waste Manag ; 51: 182-189, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26777778

RESUMO

The aim of the study is the recovery by thermal treatment of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, on the basis of the different phase change temperatures of the two metal-bearing phases. ASR (Automotive Shredder Residue), containing 68% of carbon, was added to the mixture to act as a reductant to metallic Zn of the zinc-bearing phases. The mixture was subsequently heated in different atmospheres (air, CO2 and N2) and at different temperatures (900°C, 1000°C and 1200°C) and stoichiometric excess of ASR (300%, 600% and 900%). Characterization of the mixture and of the residues of thermal treatment was carried out by chemical analysis, TGA/DTA, SEM and XRD. The results show that recovery of 99% of zinc (grade 97%) is achieved at 1000°C in N2 with a stoichiometric excess of car-fluff of 900%. This product could be suitable for production of new batteries after refining by hydrometallurgical way. Recovery of Mn around 98% in the residue of the treatment is achieved at any temperature and atmosphere tested with a grade of 57% at 900% excess of car-fluff. This residue is enriched in manganese oxide and could be used in the production of iron-manganese alloys.


Assuntos
Fontes de Energia Elétrica , Resíduos Industriais/análise , Manganês/análise , Reciclagem/métodos , Gerenciamento de Resíduos/métodos , Zinco/análise , Automóveis , Carbono , Ferro/análise , Compostos de Manganês/análise , Óxidos/análise , Temperatura
2.
Waste Manag ; 32(10): 1945-51, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22677015

RESUMO

The aim of this paper is the recovery of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, containing 40.9% of Mn and 30.1% of Zn, after preliminary physical treatment followed by removal of mercury. Separation of the metals has been carried out on the basis of their different boiling points, being 357°C and 906°C the boiling point of mercury and zinc and 1564°C the melting point of Mn(2)O(3). Characterization by chemical analysis, TGA/DTA and X-ray powder diffraction of the mixture has been carried out after comminution sieving and shaking table treatment to remove the anodic collectors and most of chlorides contained in the mixture. The mixture has been roasted at various temperatures and resident times in a flow of air to set the best conditions to remove mercury that were 400°C and 10 min. After that, the flow of air has been turned into a nitrogen one (inert atmosphere) and the temperatures raised, thus permitting the zinc oxide to be reduced to metallic zinc by the carbon present in the original mixture and recovered after volatilization as a high grade concentrate, while manganese was left in the residue. The recovery and the grade of the two metals, at 1000°C and 30 min residence time, were 84% and 100% for zinc and 85% and 63% for manganese, respectively. The recovery of zinc increased to 99% with a grade of 97% at 1200°C and 30 min residence time, while the recovery and grade of manganese were 86% and 87%, respectively, at that temperature. Moreover, the chlorinated compounds that could form by the combustion of the plastics contained in the spent batteries, are destroyed at the temperature required by the process.


Assuntos
Manganês/isolamento & purificação , Reciclagem , Zinco/isolamento & purificação , Temperatura Alta , Mercúrio/isolamento & purificação , Termogravimetria , Difração de Raios X
3.
J Environ Manage ; 77(3): 205-11, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16048735

RESUMO

The optimum conditions for the recovery of copper from a contaminated soil by using the soil flushing technique are evaluated. Tests on a soil artificially contaminated with copper chloride were carried out in order to evaluate the influence of the speed of percolation and of the chelating agent concentration (aqueous solution of an ethylendiaminotetraacetic acid di-sodium salt Na2-EDTA). At pH=7.3 an efficiency up to 93.9% for copper extraction was achieved by flushing 500 ml of Na2-EDTA 0.05 M solution and 100 ml of pure water at 0.792 cm/h. At these operating conditions the formation of EDTA complexes with other competitive cations (calcium and iron) was negligible. The experimental results were in agreement with the ones obtained using a model describing the chemistry of metal extraction. This model assessed that above pH=6 the formation of calcium and iron EDTA complexes was excluded and only the chelation of copper was allowed. The recovery of 91.6% of EDTA was also achieved by evaporating and acidifying the extracted solution: after filtration, solid EDTA was obtained, through the addition of sodium hydroxide Na2-EDTA. About 99.5% of the extracted copper was finally precipitated under alkaline conditions from the liquid phase.


Assuntos
Quelantes/química , Ácido Edético/química , Poluição Ambiental/prevenção & controle , Metais Pesados/química , Poluentes do Solo/análise , Precipitação Química , Filtração
4.
Waste Manag ; 22(8): 883-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12423049

RESUMO

In this work the development of a process for the recovery of copper from contaminated industrial soils is presented. Experimental tests on a standard soil contaminated with a solution of copper chloride were carried out. The metal was extracted from the contaminated soil by flushing with a 0.1 M aqueous solution of an ethylenediaminetetraacetic acid (EDTA) sodium salt. A maximum copper extraction efficiency of about 60% was observed. Copper was then separated from the extracted solution by precipitation with sodium hydroxide after addition of ferric sulfate.


Assuntos
Cobre/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Quelantes/química , Ácido Edético/química , Resíduos Industriais
5.
Waste Manag ; 22(8): 925-30, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12423056

RESUMO

The performance of products arising from the stabilization/solidification of slags from lead batteries recycle into a Portland cement matrix has been evaluated not only in order to get a stabilized waste to be disposed of according to the current legislation, but also to obtain a recyclable material, with both economic and environmental benefits. Under this respect a detailed characterization of raw slags has been performed and different slag-cement samples have been prepared by varying the slag content. The parameters related to the cementation process have been evaluated and a series of tests on the final waste forms have been carried out, aimed at assessing both mechanical performance and leaching behaviour. In spite of the acceptable values for flexural, compressive and tensile strength, however, the high release of lead from the solidification products seems to be a limiting factor for a reusable material. While explanations of such phenomenon are given (high alkalinity of Portland cement; early "doping" of cementitious components by lead in the amorphous state), the main conclusion of the research work is that further efforts should be addressed to the adoption of a different or a modified incorporation matrix.


Assuntos
Conservação dos Recursos Naturais , Fontes de Energia Elétrica , Chumbo , Meio Ambiente , Poluentes Ambientais/análise , Estudos de Viabilidade , Teste de Materiais
6.
Waste Manag ; 22(6): 605-10, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12214971

RESUMO

Results are presented of experiments performed to optimize the solidification/stabilization system for metallic elements in aqueous solution. This system involves mixing cement and a solution of metallic elements in a conventional mixer: the paste thus obtained is transferred drop by drop into a recipient filled with an aqueous solution of NaOH at 20% by weight, in which it solidifies immediately. The separate use of chloride solutions of Li+, Cr3+, Pb2+ and Zn2+ makes it possible to obtain granules displaying various levels of compressive strength. Three different inertization matrices were used in the experiments, the first consisting solely of Portland cement, the second of Portland cement and a superplasticizer additive, and the third of Portland cement partially replaced with silica-fume and superplasticizer. The results of the tests performed showed a very low level of leaching into the alkaline solidification solution for Cr3+, the quantity leached being under 2% as against higher levels for the other metallic elements. For all the considered elements, the best results were obtained by using silica-fume in the inertization matrix.


Assuntos
Resíduos Industriais , Metais Pesados/química , Silicatos/química , Gerenciamento de Resíduos/métodos , Adsorção , Cromo/química , Materiais de Construção , Humanos , Íons , Chumbo/química , Lítio/química , Solubilidade , Água , Zinco/química
7.
Minerva Med ; 91(5-6): 117-22, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-11084846

RESUMO

Primary hyperparathyroidism is a rather frequent pathology characterised by hypersecretion of parathormone (PTH) which is caused by adenomas in 85% of all cases. At clinical onset, the most common symptoms are hypercalcemia-related (pain due to kidney stones, polyuria, gastrointestinal and neurological disorders) while rarer symptoms are due to brown tumors, expansive lesions often found in fibro-cystic osteitis. A case in which the patient showed recurrent mandibular brown tumors as initial clinical symptoms of primary hyperparathyroidism is described. This patient was examined for hypercalcemia, and a tumor mass at the left inferior mandibular branch was found. The patient had undergone surgical removal of a tumor in the left mandibular some years before, which was diagnosed as osteoclastoma. Primary hyperparathyroidism was diagnosed during recovery, and surgical removal of the parathyroid adenoma and mandibular tumor was performed. A histological diagnosis of large cell brown tumor was made. A microscopic observation of brown tumors which are made up of large multinuclear osteoclastic cells can often be confused with other large cell tumors during diagnosis. It is therefore necessary to exclude the presence of hyperparathyroidism with ionised calcium and, in cases of high values, intact PTH (iPTH), before performing a histological diagnosis of a large cell bone tumor. Throughout the course of primary hyperparathyroidism, brown tumors might appear in the absence of other specific symptoms and localize at the level of a single bone segment.


Assuntos
Adenoma/diagnóstico , Granuloma de Células Gigantes/diagnóstico , Hiperparatireoidismo/diagnóstico , Doenças Mandibulares/diagnóstico , Neoplasias das Paratireoides/diagnóstico , Adenoma/patologia , Adenoma/cirurgia , Adulto , Diagnóstico Diferencial , Feminino , Tumor de Células Gigantes do Osso/diagnóstico , Tumor de Células Gigantes do Osso/cirurgia , Granuloma de Células Gigantes/diagnóstico por imagem , Granuloma de Células Gigantes/patologia , Humanos , Hiperparatireoidismo/complicações , Mandíbula/patologia , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/patologia , Neoplasias Mandibulares/diagnóstico , Neoplasias Mandibulares/cirurgia , Neoplasias das Paratireoides/patologia , Neoplasias das Paratireoides/cirurgia , Paratireoidectomia , Radiografia Panorâmica , Recidiva , Tomografia Computadorizada por Raios X
8.
Int J Cardiol ; 74(2-3): 139-44, 2000 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-10962113

RESUMO

BACKGROUND: A major cause of morbidity in type I diabetes is congestive heart failure due predominantly to left ventricular diastolic dysfunction. The mechanism of diastolic dysfunction remains unknown and does not relate to blood pressure, microvascular complications and glycated haemoglobin. Hyperglycaemia is the hallmark of diabetes and is a potential determinant of left ventricular diastolic dysfunction. OBJECTIVE: To determine whether acute hyperglycaemia can induce changes in left ventricular diastolic function in normal subjects similar to those observed in insulin-dependent diabetes mellitus (IDDM). DESIGN: Cross-sectional study. SETTING: London teaching hospital. SUBJECTS: Sixteen twins from eight identical twin pairs discordant for IDDM (age 18-38 years, five male) were studied; none had a history or evidence of myocardial ischaemia, valvular or primary heart muscle disease, systemic hypertension or nephropathy. INTERVENTIONS: Non-diabetic twins underwent a hyperglycaemic clamp at 10 mmol/l. MAIN OUTCOME MEASURES: Doppler echocardiography was performed in basal condition in identical twin pairs discordant for IDDM and repeated in the non-diabetic twins during hyperglycaemia. Blood glucose, insulin and catecholamines were measured at baseline and during hyperglycaemia. RESULTS: Transmitral Doppler E/A velocity ratio was significantly lower in diabetic than non-diabetic twins at baseline (1.44 (0.38) vs. 1.51 (0.19), P<0.05). Glucose infusion in the non-diabetic twins resulted in an increase in their E/A ratio (1.51 (0.19) vs. 1.82 (0. 47), P<0.05) due to an increase in E velocity (68 (12) to 64.7 (10. 7), P<0.05) and a decrease in the peak A velocity (42.7 (3.85) to 38. 0 (4.1), P<0.05). No significant changes were observed in peak E velocity or isovolumic relaxation time in the non-diabetic twins between baseline and hyperglycaemia. CONCLUSIONS: The alterations in left ventricular diastolic function induced by acute hyperglycaemia and consequent increase in plasma catecholamines do not mimic those demonstrated in IDDM patients.


Assuntos
Doenças em Gêmeos , Ecocardiografia Doppler , Hiperglicemia/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Adolescente , Adulto , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Técnica Clamp de Glucose , Humanos , Modelos Lineares , Masculino , Probabilidade , Valores de Referência , Sensibilidade e Especificidade , Gêmeos Monozigóticos , Função Ventricular Esquerda
9.
Diabetes Care ; 23(2): 228-33, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10868836

RESUMO

OBJECTIVE: To determine the isotypes and clonality of antibodies to GAD (GADA) and IA-2 (IA-2A) in patients with type 1 and type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied the following consecutive series of patients who attended a diabetes center for antibodies to GADA and IA-2A: 52 newly diagnosed type 1 diabetic patients, 199 type 2 diabetic patients, 200 control patients, and a cohort of 34 nondiabetic identical twins of patients with type 1 diabetes (15 of whom developed diabetes) who were followed prospectively. RESULTS: GADA or IA-2A were detected in 37 (71%) type 1 diabetic patients compared with only 10 (5%) type 2 diabetic patients (P<0.0001). Both GAD and IA-2 antibodies, regardless of the type of diabetes, were usually subclass restricted to IgG1 and were polyclonal. IgM, IgG3, and IgE isotypes were also detected, but all isotypes of GADA and IA-2A were less prevalent than IgG1 (P<0.017 for either antibody). There was no evidence of spreading or switching of isotypes before the onset of type 1 diabetes. CONCLUSIONS: These observations suggest that the pathogenesis of antigen-specific antibodies in type 1 and type 2 diabetes is similar and probably involves a chronic nonrandom antigen-driven polyclonal B-cell activation that is consistent with a Th1-type immune response.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/imunologia , Glutamato Descarboxilase/imunologia , Isotipos de Imunoglobulinas/sangue , Isoenzimas/imunologia , Adulto , Idade de Início , Estudos de Coortes , Europa (Continente)/etnologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Valores de Referência , Gêmeos Monozigóticos , População Branca
10.
Hum Immunol ; 60(9): 848-54, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10527392

RESUMO

To verify whether autoimmune markers related to nervous system structures and other autoimmunity indexes present in diabetes mellitus are associated with subclinical neuropathy, we examined 48 non-insulin-dependent diabetic patients with and without neuroelectrophysiological alterations. Nerve conduction velocity at the external sciatic-popliteal nerve, at the sural nerve, at the median and ulnar nerves level has been evaluated. Autoimmunity was investigated by evaluating glutamic acid decarboxylase (GAD-Ab), insulin (IAA), GM3, GD3 and GT1b gangliosides, pancreatic islet cell (IC-A) and anti-nervous-tissue autoantibody presence. Nerve conduction velocities were decreased in 72.9% of diabetic patients. Anti-insulin antibodies were detected in seven non-insulin created diabetic patients and in higher amount in subjects with (17.1%) than in those without (7.7%) asymptomatic neuropathy. Anti-GM3 antibodies were detected in four diabetic patients all of whom presented neurological complication. A significant correlation has been found between neurological damage and presence of anti-insulin antibodies (p<0.05). In the case of GM3 autoantibody, a similar result was obtained, but the data failed to reach statistical significance. Our data demonstrate that autoimmunity might play a role in the development of peripheral neuropathy.


Assuntos
Autoimunidade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/imunologia , Neuropatias Diabéticas/imunologia , Gangliosídeos/imunologia , Glutamato Descarboxilase/imunologia , Idoso , Biomarcadores , Feminino , Gangliosídeo G(M3)/imunologia , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Nervo Ulnar/fisiopatologia
11.
Diabetes Care ; 22(9): 1458-61, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10480509

RESUMO

OBJECTIVE: Type 1 diabetes is more prevalent in Europeans than it is in Asians. The disease is associated with autoantibodies to GAD65 and a protein tyrosine phosphatase-like molecule (IA-2). The frequency of GAD antibodies in Asian patients with type 1 diabetes may be lower than that in Europeans. No data are available on IA-2 antibodies in Asians. We tested antibodies to GAD65 and IA-2ic (the intracellular fragment containing the antibody epitope) in Filipino diabetic patients because this population has mixed European and aboriginal racial origins. RESEARCH DESIGN AND METHODS: A cross-sectional study of antibodies to GAD65 and IA-2ic was performed on a consecutive series of 91 type 1 diabetic patients, 74 type 2 diabetic patients, and 100 control subjects attending a diabetes clinic in Manila, the Republic of the Philippines. All subjects were <40 years of age, with a mean age +/- SD of 24.8+/-9.8, 34.3+/-5.8, and 25.8+/-8.0 years, respectively. Diagnosis of type 1 diabetes was determined clinically and confirmed by baseline C-peptide. RESULTS: Of 91 type 1 diabetic patients, antibodies to GAD65 were detected in 25 (27.4%), but antibodies to IA-2ic were found in only 8 (8.8%) (P = 0.002); neither autoantibody was detected in either the type 2 diabetic or control subjects. Of the 25 recently diagnosed type 1 diabetic patients (disease duration <2.0 years), autoantibodies to GAD65 were detected in 14 (56%), but those to IA-2ic in only 4 (16%) (P = 0.007); GAD65 antibodies were detected in only 4 (6%) of 66 patients with a longer disease duration (P = 0.0004). Comparison with recently diagnosed European type 1 diabetic patients of age and disease duration similar to that of the Filipinos indicated that IA-2ic antibodies, unlike GAD antibodies, were significantly less prevalent in Filipino type 1 diabetic patients (P = 0.0007). CONCLUSIONS: This is the first study investigating the prevalence and pattern of humoral immune response in type 1 diabetic patients from the Philippines. Antibodies to IA-2ic, unlike GAD antibodies, were infrequent. Patterns of immune responses to type 1 diabetes-associated antigens may differ worldwide, with important implications for prediction of the disease and the potential for antigen-specific therapy.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Glutamato Descarboxilase/imunologia , Isoenzimas/imunologia , Proteínas Tirosina Fosfatases/imunologia , Adulto , Estudos Transversais , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 1/imunologia , Epitopos , Europa (Continente) , Feminino , Humanos , Masculino , Filipinas/etnologia , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Valores de Referência
12.
Diabetes Metab Res Rev ; 15(1): 13-20, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10398542

RESUMO

BACKGROUND: Alterations in proteoglycan metabolism are involved in the pathogenesis of diabetic nephropathy. The aim of this study is to evaluate the effects of high glucose on proteoglycan production and to find a reliable in vitro model for the study of diabetic nephropathy. METHODS: A clone of mouse glomerular epithelial cells was cultured in media containing elevated (30 mmol) and physiological (5 mmol) glucose, or iso-osmolar (30 mmol) mannitol concentrations. We evaluated the synthesis of 35SO4-labeled molecules and the amount of proteoglycans by Sepharose CL6B and DEAE-Sephacel chromatographies. RESULTS: A clear decrease (56%) in total cell-layer proteoglycan synthesis was induced by 30 mmol glucose, in comparison with normal glucose. A reduction of 25% in medium associated proteoglycan synthesis was observed in high glucose cultured cells. After Sepharose CL6B, in cells cultured in high glucose, cell layer heparansulphate proteoglycan-I (Kav 6B 0. 04) synthesis was reduced by about 81%, heparansulphate proteoglycan-II (Kav 6B 0.21) by about 87% and heparansulphate glycosaminoglycan (Kav 0.4-0.8) by about 91%, respectively. In mannitol-incubated cells the reductions observed were less evident and not significantly different from those in normal glucose. CONCLUSIONS: These results indicate that (1) glomerular epithelial cells play a central role in proteoglycan synthesis, (2) high glucose modifies the amount and influences the different species production of these macromolecules, while osmotic forces seem to be only partially involved in these effects, and (3) this cellular clone of glomerular epithelial cells can represent a reliable in vitro model for the study of the mechanisms involved in diabetic nephropathy.


Assuntos
Glucose/administração & dosagem , Heparitina Sulfato/biossíntese , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Animais , Células Cultivadas , Cromatografia , Meios de Cultura , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glucose/farmacologia , Proteoglicanas de Heparan Sulfato/biossíntese , Manitol/farmacologia , Camundongos
13.
Diabetologia ; 42(2): 146-50, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10064093

RESUMO

To determine the concordance rate for Type II (non-insulin-dependent) diabetes mellitus in monozygotic twin pairs, initially ascertained discordant for diabetes, we carried out a prospective study on 44 non-diabetic subjects, each of whom had a sibling twin with diabetes (21 men, 23 women, median age 55 years, interquartile range 47-65). The subjects were referred as discordant for Type II diabetes. The twin pairs were part of the British Diabetic Twin Study and ascertained between May 1968 and January 1998. These subjects underwent an OGTT at time of referral and periodically thereafter. The mean follow-up was 8 years (range 0-18 years) and data were collected until January 1996. The percentage of twins who developed Type II diabetes was assessed by standard actuarial life-table methods and the pairwise concordance rate, that is the proportion of concordant pairs over the sum of concordant and discordant pairs, was calculated. The observed rates of concordance for Type II diabetes at 1, 5, 10, and 15 years follow-up were 17, 33, 57, and 76%, respectively. The concordance rate for any abnormality of glucose metabolism (either Type II diabetes or impaired glucose tolerance) at 15 years follow-up was 96%. The concordance rate for Type II diabetes in monozygotic twins is very high even in twins initially ascertained discordant for diabetes.


Assuntos
Análise Atuarial , Diabetes Mellitus Tipo 2/genética , Gêmeos Monozigóticos , Feminino , Intolerância à Glucose , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Estudos Prospectivos , Fatores de Risco
14.
Minerva Endocrinol ; 24(3-4): 97-102, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10953723

RESUMO

BACKGROUND: The purpose of this study was to analyze diastolic function in two different populations of young patients affected by insulin dependent diabetes mellitus (IDDM), with and without systemic diabetic complications, and to compare the results obtained at rest with those obtained during isometric exercise. METHODS: Forty-five IDDM diabetic patients were studied. On the basis of presence or absence of systemic diabetic complications (nephropathy and retinopathy) patients were divided into two groups. Group I (20 patients) without and Group II (25 patients) with diabetic complications. Diastolic function parameters were measured by Doppler echocardiography at rest and during isometric exercise. The two groups were similar regarding age, metabolic control and insulin dosage but there were significant differences in diastolic and systolic blood pressure and heart rate between the two groups, the patients with complications showing higher values (p < 0.001, p < 0.005, p < 0.01 respectively). RESULTS: Group II already presented at rest alterations of diastolic function parameters respect to Group I with a marked increase of: peak velocity of late left ventricular filling (peakA cm/sec), (60.1 +/- 13.4 versus 48.4 +/- 8.9, p < 0.01); late left ventricular filling integral (A area), (6.5 +/- 1.4 versus 5.0 +/- 0.8, p < 0.05); late left ventricular filling integral over total filling (A area/total area), (0.31 +/- 0.06 versus 0.26 +/- 0.06, p < 0.01). There was a decrease of E/A ratio in Group II versus Group I (1.5 +/- 0.32 versus 1.9 +/- 0.5, p < 0.05). During isometric exercise these changes became even more pronounced in patients with complications and in this group there was a marked decrease of flow integral of early left ventricular filling over total filling (E area/total area), (0.57 +/- 0.09 versus 0.68 +/- 0.07, p < 0.01). CONCLUSIONS: In conclusion, young IDDM patients with complications show an impairment of diastolic function more pronounced than those without. These changes are more evident during isometric exercise. Stress Doppler echocardiography is a reliable tool to detect early diastolic dysfunction in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Ecocardiografia Doppler , Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Função Ventricular Esquerda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade
15.
Panminerva Med ; 40(3): 204-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9785918

RESUMO

BACKGROUND: The purpose of this study was to analyze diastolic function in two different populations of young patients affected by insulin dependent diabetes mellitus (IDDM), with and without systemic diabetic complications, and to compare the results obtained at rest with those obtained during isometric exercise. METHODS: Forty-five IDDM diabetic patients were studied. On the basis of presence or absence of systemic diabetic complications (nephropathy and retinopathy) patients were divided into two groups. Group I (20 patients) without and Group II (25 patients) with diabetic complications. Diastolic function parameters were measured by Doppler echocardiography at rest and during isometric exercise. The two groups were similar regarding age, metabolic control and insulin dosage but there were significant differences in diastolic and systolic blood pressure and heart rate between the two groups, the patients with complications showing higher values (p < 0.001, p < 0.005, p < 0.01 respectively). RESULTS: Group II already presented at rest alterations of diastolic function parameters respect to Group I with a marked increase of: peak velocity of late left ventricular filling (peakA cm/sec), (60.1 +/- 13.4 versus 48.4 +/- 8.9, p < 0.01); late left ventricular filling integral (A area), (6.5 +/- 1.4 versus 5.0 +/- 0.8, p < 0.05); late left ventricular filling integral over total filling (A area/total area), (0.31 +/- 0.06 versus 0.26 +/- 0.06, p < 0.01). There was a decrease of E/A ratio in Group II versus Group I (1.5 +/- 0.32 versus 1.9 +/- 0.5, p < 0.05). During isometric exercise these changes became even more pronounced in patients with complications and in this group there was a marked decrease of flow integral of early left ventricular filling over total filling (E area/total area), (0.57 +/- 0.09 versus 0.68 +/- 0.07, p < 0.01). CONCLUSIONS: In conclusion, young IDDM patients with complications show an impairment of diastolic function more pronounced than those without. These changes are more evident during isometric exercise. Stress Doppler echocardiography is a reliable tool to detect early diastolic dysfunction in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Disfunção Ventricular Esquerda , Adolescente , Adulto , Diabetes Mellitus Tipo 1/complicações , Ecocardiografia Doppler , Exercício Físico , Teste de Esforço , Humanos
16.
Angiology ; 49(5): 339-48, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9591525

RESUMO

In this review the indications for the available treatments for dyslipidemias in the prevention of coronary heart disease (CHD) are considered, and their efficacy according to the latest studies is analyzed. As data sources the authors used the main multicenter studies performed in the last twenty years to evaluate primary and secondary prevention of CHD by correcting dyslipidemias as well as the results of meta-analyses of these studies. All treatments considered were found effective in preventing CHD morbidity and mortality to some extent. In particular, the combination of diet with niacin or hydroxymethylglutaryl coenzyme A (HMG CoA) reductase inhibitors seems to give the best results. These drugs induce a marked reduction of total and low-density lipoprotein (LDL) cholesterol and an increase of high-density lipoprotein (HDL) cholesterol concentrations. The use of diet, niacin, and HMG CoA reductase inhibitors reduces total as well as specific mortality. Treatment of dyslipidemia to prevent CHD depends on the pattern and severity of dyslipidemia, the presence of overt CHD, and the patient's response to diet. Pharmacologic treatment should be started only after dietary modifications have been tried and must be combined with diet. Drug side effects must also be considered, for they may affect patient compliance. High levels of total and LDL and low levels of HDL cholesterol are major risk factors for coronary atherosclerosis. Correcting lipid abnormalities can reduce the risk of development or progression of CHD. Diet and drugs are the main instruments available to normalize lipid levels. The choice of drug to combine with diet must be based on its specific effects on lipid metabolism, side effects, and efficacy in reducing CHD.


Assuntos
Doença das Coronárias/prevenção & controle , Hiperlipidemias/terapia , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Terapia Combinada , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/prevenção & controle , Doença das Coronárias/mortalidade , Doença das Coronárias/fisiopatologia , Progressão da Doença , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipidemias/sangue , Hiperlipidemias/dietoterapia , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/efeitos adversos , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Metabolismo dos Lipídeos , Metanálise como Assunto , Estudos Multicêntricos como Assunto , Niacina/uso terapêutico , Cooperação do Paciente , Prevenção Primária , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
17.
Paediatr Perinat Epidemiol ; 9(3): 320-30, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7479280

RESUMO

This report describes a cohort study of over 5000 infants and their mothers who participated in a cord blood serosurvey designed to examine the relationship between maternal exposure to Lyme disease and adverse pregnancy outcome. Based on serology and reported clinical history, mothers of infants in an endemic hospital cohort are 5 to 20 times more likely to have been exposed to B. burgdorferi as compared with mothers of infants in a control hospital cohort. The incidence of total congenital malformations was not significantly different in the endemic cohort compared with the control cohort, but the rate of cardiac malformations was significantly higher in the endemic cohort [odds ratio (OR) 2.40; 95% confidence interval (CI) 1.25, 4.59] and the frequencies of certain minor malformations (haemangiomas, polydactyly, and hydrocele), were significantly increased in the control group. Demographic variations could only account for differences in the frequency of polydactyly. Within the endemic cohort, there were no differences in the rate of major or minor malformations or mean birthweight by category of possible maternal exposure to Lyme disease or cord blood serology. The disparity between observations at the population and individual levels requires further investigation. The absence of association at the individual level in the endemic area could be because of the small number of women who were actually exposed either in terms of serology or clinical history. The reason for the findings at the population level is not known but could be because of artifact or population differences.


Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , Anormalidades Congênitas/microbiologia , Sangue Fetal/microbiologia , Doença de Lyme/complicações , Complicações Infecciosas na Gravidez , Adulto , Animais , Mordeduras e Picadas , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Anormalidades Congênitas/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/microbiologia , Humanos , Incidência , Lactente , Doença de Lyme/sangue , Doença de Lyme/epidemiologia , Doença de Lyme/transmissão , New York/epidemiologia , Razão de Chances , Gravidez , Complicações Infecciosas na Gravidez/sangue , Complicações Infecciosas na Gravidez/epidemiologia , Prevalência , Carrapatos
18.
Biochem Med Metab Biol ; 53(2): 92-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7710774

RESUMO

An impairment of protein charge selectivity has been invoked to explain the initial anionic proteinuria in diabetic nephropathy. The aims of this work were to investigate charge and size protein perm-selectivity abnormalities in experimental diabetes and to monitor these changes over time after diabetes induction. Diabetes was induced in 56 Sprague-Dawley male rats by streptozotocin; the control group was represented by 38 normal rats. Blood glucose, body weight, urine volumes, and proteinuria in 24-h urine collections were evaluated at 3, 6, 9, and 12 months of diabetes. The Bradford method and mono- and bidimensional gel electrophoresis were used to determine and characterize proteinuria. Body weight increase was lower (P < 0.05, P < 0.0001, P < 0.05 at 3, 6, and 12 months, respectively), urine volumes were greater (P < 0.001, P < 0.005, P < 0.05 at 6, 9, and 12 months, respectively) and the proteinuria was significantly increased (P < 0.05 at 3 months, P < 0.001 at 6 months, P < 0.01 at 9 months, and P < 0.05 at 12 months) in diabetic rats compared with the control group. When the charge and the size of urine proteins were considered, small (30 kDa) and anionic proteins were found to be mainly excreted in diabetic rats, at 3 months of the disease; at 6 months, higher amounts of albumin and cationic proteins with higher molecular weight (50 kDa) were also found in the urine; at 9 and 12 months the changes previously described were associated with an excretion of proteins weighing about 75 kDa.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diabetes Mellitus Experimental/complicações , Proteinúria/fisiopatologia , Albuminúria/urina , Animais , Glicemia/análise , Peso Corporal , Nefropatias Diabéticas/urina , Rim/química , Masculino , Proteínas/química , Proteinúria/complicações , Ratos , Ratos Sprague-Dawley
19.
Minerva Chir ; 48(20): 1219-22, 1993 Oct 31.
Artigo em Italiano | MEDLINE | ID: mdl-8121594

RESUMO

Small bowel leiomyosarcomas are uncommon potentially curable tumors, unfortunately diagnosed at an advanced stage. The Authors report one case of leiomyosarcoma of the small bowel, with an eight-day history of severe abdominal pain, operated on, in emergency, for perforation with peritonitis. A review of English literature on this subject is reported.


Assuntos
Neoplasias do Íleo , Leiomiossarcoma , Emergências , Feminino , Humanos , Neoplasias do Íleo/diagnóstico , Neoplasias do Íleo/cirurgia , Leiomiossarcoma/diagnóstico , Leiomiossarcoma/cirurgia , Pessoa de Meia-Idade
20.
Acta Diabetol ; 30(3): 138-42, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8111073

RESUMO

A possible loss in kidney charge permselectivity of proteins before any manifestation of nephropathy has been sought in type 2 (non-insulin-dependent) diabetes by assessing the clearances of proteins differing in charge and/or size (anionic and cationic immunoglobulins, albumin). Eighty-five consecutive outpatients with type 2 diabetes were studied and compared with 101 normal subjects. Of the patients, 14.1% were microalbuminuric and 2.3% macroalbuminuric. A significant increase in protein clearances was observed in diabetic patients in comparison with normal subjects: the median of albumin clearance was 0.09 ml/min, interquartile range (IR) 0.04-0.31 (P < 0.01 vs normals); that of anionic immunoglobulins (IgG4) 0.02 ml/min, IR 0.04-0.05 (P < 0.005 vs normals); and that of neutral/cationic immunoglobulins (IgG) 0.13 ml/min, IR 0.07-0.19 (P < 0.01 vs normals). The anionic/cationic immunoglobulin ratio median was 0.22, IR 0.11-0.43, and exceeded the upper limit of normal values in 29.4% of all patients. IgG4 clearance was positively correlated with albumin clearance (r = 0.72) and with IgG clearance (r = 0.98). Nevertheless anionic immunoglobulin clearance was increased in a number of patients (17.3%) with normal IgG excretion and even in patients (15.1%) with normal albumin clearance. Clearances of IgG4 and IgG, but not that of albumin, were correlated with the duration of diabetes. Thus, an increased anionic/cationic IgG ratio in type 2 diabetes highlights a charge selectivity defect in protein permselectivity; this selective proteinuria may reflect more accurately than does microalbuminuria an early kidney abnormality in this form of diabetes.


Assuntos
Albuminúria , Diabetes Mellitus Tipo 2/fisiopatologia , Imunoglobulina G/urina , Proteinúria , Adulto , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Feminino , Humanos , Imunoglobulina G/classificação , Masculino , Pessoa de Meia-Idade , Valores de Referência
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