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1.
Diabet Med ; 27(5): 498-515, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20536945

RESUMO

Polycystic ovary syndrome (PCOS) is a risk factor for Type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD), but these risks are poorly defined. This study aimed to evaluate the evidence for these risks and whether screening and risk reduction are feasible. Medline reviews and data quality analysis were used using standard tools. Results showed that (i) polycystic ovary syndrome is a risk factor forT2DM but the magnitude of risk is uncertain, (ii) fasting plasma glucose is an inadequate screening test forT2DM in this population and the oral glucose tolerance test is superior, (iii) the identification of women with PCOS for diabetes screening is constrained by current diagnostic criteria for PCOS; however, women with oligomenorrhoea and those with diagnosed PCOS and obesity or a family history of T2DM are at highest risk, (iv) risk factors for T2DM are improved by weight loss interventions and by metformin. However, no studies have determined whether T2DM incidence is reduced, (v) polycystic ovary syndrome is associated with cardiovascular disease (CVD) risk factors but data on CVD incidence are weak, (vi) risk factors for CVD are improved by the same interventions and statins and (vi) no studies have evaluated whether CVD incidence is reduced. While PCOS has important metabolic associations, and short-term interventions reduce risk factors for T2DM and CVD, data on prevalence and incidence of T2DM and particularly CVD are poor. There is a need for a clear definition of PCOS, for diabetes screening protocols and for long-term studies to determine whether risks can be reduced.


Assuntos
Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/prevenção & controle , Síndrome do Ovário Policístico/complicações , Glicemia/análise , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Jejum , Feminino , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/uso terapêutico , Incidência , Programas de Rastreamento/métodos , Metformina/uso terapêutico , Prevalência , Fatores de Risco , Redução de Peso
2.
Diabet Med ; 25(6): 662-70, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18435781

RESUMO

AIM: To examine the impact of inhaled human insulin (Exubera, EXU) on patient or physician willingness to adopt insulin after oral glucose-lowering agent failure. METHODS: During a randomized controlled trial in primary, secondary and tertiary care in Europe and North America, 739 patients using >or= 2 oral glucose-lowering agents with glycated haemoglobin (HbA(1c)) >or= 8.0% were assigned to two treatment groups: Group 1 (standard care with the option of EXU) or Group 2 (standard care only). Standard care included adjusting oral therapy (optimizing current regimen or adding/omitting agents) and/or initiating subcutaneous (s.c.) insulin. The primary endpoint was difference in HbA(1c) between randomized groups at 26 weeks. Secondary outcomes included differences in the rate of uptake of insulin therapy, proportion achieving satisfactory glycaemic control, treatment satisfaction and safety outcomes. RESULTS: At baseline, insulin was initiated by more [odds ratio 6.0; 95% confidence interval (CI) 4.2 to 8.8; P < 0.0001] patients in Group 1 (86.2%; 76.7% EXU plus 9.5% s.c.) than Group 2 (50.7%; s.c. insulin only). At 26 weeks, mean (sd) changes in HbA(1c) from baseline were -2.0% (1.2%) and -1.7% (1.3%) in Groups 1 and 2, respectively, a difference of -0.2% (95% CI: -0.1% to -0.4%; P = 0.004). In Group 1, 45% of patients achieved an HbA(1c)

Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Administração por Inalação , Adulto , Idoso , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Vias de Administração de Medicamentos , Europa (Continente) , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte , Resultado do Tratamento
3.
J Clin Invest ; 104(9): R33-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10545530

RESUMO

The transcription factor insulin promoter factor-1 (IPF-1) plays a central role in both the development of the pancreas and the regulation of insulin gene expression in the mature pancreatic beta cell. A dominant-negative frameshift mutation in the IPF-l gene was identified in a single family and shown to cause pancreatic agenesis when homozygous and maturity-onset diabetes of the young (MODY) when heterozygous. We studied the role of IPF-1 in Caucasian diabetic and nondiabetic subjects from the United Kingdom. Three novel IPF-1 missense mutations (C18R, D76N, and R197H) were identified in patients with type 2 diabetes. Functional analyses of these mutations demonstrated decreased binding activity to the human insulin gene promoter and reduced activation of the insulin gene in response to hyperglycemia in the human beta-cell line Nes2y. These mutations are present in 1% of the population and predisposed the subject to type 2 diabetes with a relative risk of 3.0. They were not highly penetrant MODY mutations, as there were nondiabetic mutation carriers 25-53 years of age. We conclude that mutations in the IPF-1 gene may predispose to type 2 diabetes and are a rare cause of MODY and pancreatic agenesis, with the phenotype depending upon the severity of the mutation.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteínas de Homeodomínio , Transativadores/genética , Adulto , Idoso , Western Blotting , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Glucose/metabolismo , Humanos , Insulina/genética , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Fosforilação , Transcrição Gênica
4.
J Hum Hypertens ; 20(12): 923-31, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17036043

RESUMO

A blood pressure (BP) difference between arms was first reported over 100 years ago. Knowledge of its prevalence and relevance to the accurate measurement of BP remains poor. Current hypertension guidelines do not emphasise it. The objectives of this study were to establish the best estimate of prevalence of the inter-arm difference (IAD) in the population, to consider its implications for accurate BP measurement and treatment, and to discuss its aetiology and potential as a risk marker for cardiovascular disease. Systematic literature review was carried out. The data sources were Medline EMBASE and CINAHL databases, and Index of Theses. Studies reporting prevalence rates of IAD were retrieved and considered for inclusion against explicit methodological criteria. Point prevalence rates were extracted and weighted mean prevalence rates calculated. The main outcome measures were weighted mean prevalences of systolic IAD > or =10 and > or =20 mm Hg and of diastolic IAD > or =10 mm Hg. Thirty-one studies were identified. Most had methodological weaknesses; only four met the inclusion criteria. Pooled prevalences of the IAD from these four studies were 19.6% systolic > or =10 mm Hg (95% CI 18.0-21.3%), 4.2% systolic > or =20 mm Hg (95% CI 3.4-5.1%) and 8.1% diastolic > or =10 mm Hg (95%CI 6.9-9.2%). In conclusion, an IAD is present in a substantial number of patients and should be looked for whenever diagnosis and treatment depend on accurate measurements of BP. The importance of an IAD should be better emphasised in current hypertension management guidelines. There is evidence associating an IAD with peripheral vascular disease, raising the possibility that its presence may predict cardiovascular events.


Assuntos
Braço/irrigação sanguínea , Determinação da Pressão Arterial/métodos , Pressão Sanguínea , Algoritmos , Doenças Cardiovasculares/epidemiologia , Estudos Epidemiológicos , Humanos , Hipertensão/epidemiologia , Variações Dependentes do Observador , Prevalência
5.
Int J Pharm ; 505(1-2): 42-51, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27025293

RESUMO

The objective of this study was development of accelerated in vitro release method for peptide loaded PLGA microspheres using flow-through apparatus and assessment of the effect of dissolution parameters (pH, temperature, medium composition) on drug release rate and mechanism. Accelerated release conditions were set as pH 2 and 45°C, in phosphate buffer saline (PBS) 0.02M. When the pH was changed from 2 to 4, diffusion controlled phases (burst and lag) were not affected, while release rate during erosion phase decreased two-fold due to slower ester bonds hydrolyses. Decreasing temperature from 45°C to 40°C, release rate showed three-fold deceleration without significant change in release mechanism. Effect of medium composition on drug release was tested in PBS 0.01M (200 mOsm/kg) and PBS 0.01M with glucose (380 mOsm/kg). Buffer concentration significantly affected drug release rate and mechanism due to the change in osmotic pressure, while ionic strength did not have any effect on peptide release. Furthermore, dialysis sac and sample-and-separate techniques were used, in order to evaluate significance of dissolution technique choice on the release process. After fitting obtained data to different mathematical models, flow-through method was confirmed as the most appropriate for accelerated in vitro dissolution testing for a given formulation.


Assuntos
Química Farmacêutica/métodos , Ácido Láctico/química , Microesferas , Peptídeos/química , Ácido Poliglicólico/química , Soluções Tampão , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solubilidade , Temperatura
6.
Biochim Biophys Acta ; 1639(1): 1-7, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12943962

RESUMO

Studies have shown that polymorphisms located at positions -106 and approximately -2100 base pairs (5'ALR2) in the regulatory region of the aldose reductase gene are associated with susceptibility to microvascular complications in patients with diabetes. The aim was to investigate the functional roles of these susceptibility alleles using an in vitro gene reporter assay. Susceptibility, neutral and protective 5'ALR2/-106 alleles were transfected into HepG2 cells and exposed to excess D-glucose (D-glucose at final concentrations 14 or 28 mmol/l). Transcriptional activities were determined using a dual luciferase reporter gene assay. The "susceptibility alleles" Z-2 with C-106 had the highest transcriptional activity when compared with the "protective" combination of Z+2 with C-106 alleles (58.7+/-9.9 vs. 10.1+/-0.7; P<0.0001). Those constructs with either the Z or Z-2 in combination with the C-106 allele had significantly higher transcriptional activities when compared to those with the T-106 allele (Z/C-106, 37.4+/-5.4 vs. Z/T-106 7.7+/-1.6, P<0.003; Z-2/C-106, 58.7+/-9.9 vs. Z-2/T-106 10.9+/-0.6, P<0.0001). These results demonstrate that the Z-2/C-106 haplotype is associated with elevated transcriptional activity of the aldose reductase gene. This in turn may explain the role of these polymorphisms in the susceptibility to diabetic microvascular complications.


Assuntos
Aldeído Redutase/genética , Diabetes Mellitus/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Aldeído Redutase/metabolismo , Sequência de Bases , Capilares/fisiopatologia , Complicações do Diabetes , Genes Reporter , Predisposição Genética para Doença , Haplótipos , Humanos , Dados de Sequência Molecular
7.
Diabetes ; 46(2): 287-91, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9000706

RESUMO

Recent studies suggest that the gene encoding aldose reductase (ALR2), the enzyme that converts glucose to sorbitol, may confer susceptibility to microvascular disease. DNA from 275 British Caucasian patients with type I diabetes and 102 normal healthy control patients were typed for a (CA)n dinucleotide repeat polymorphic marker in the 5'-region of the ALR2 gene using polymorase chain reaction (PCR). A highly significant decrease in the frequency of the Z+2 allele was found in patients with nephropathy (nephropathy group) compared with those with no complications after a 20-year duration of diabetes (uncomplicated group) (12.7 vs. 38.2%, respectively, chi2 = 18.6, P < 0.00001); this was accompanied by an increase in the Z-2 allele in the nephropathy group (32.0 vs. 12.7% in the uncomplicated group). The nephropathy group also had a significant decrease in the Z/Z+2 genotype compared with the uncomplicated patients (10.7 vs. 44.7%, chi2 = 16.0, P < 0.0001) and an increased frequency of the Z/Z-2 genotype. There was no significant association with diabetic retinopathy. These results demonstrate that the ALR2 gene may play a role in susceptibility to diabetic nephropathy; individuals with the Z+2 allele are more than seven times less likely to develop diabetic renal disease than those without this marker. This marker may prove valuable in screening for patients with diabetic nephropathy at diagnosis of diabetes.


Assuntos
Aldeído Redutase/genética , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Diabetes Mellitus Tipo 1/complicações , Retinopatia Diabética/genética , Feminino , Frequência do Gene , Genes , Humanos , Masculino , Repetições de Microssatélites , Polimorfismo Genético
8.
J Clin Endocrinol Metab ; 100(10): E1362-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26259131

RESUMO

CONTEXT: GLIS3 (GLI-similar 3) is a member of the GLI-similar zinc finger protein family encoding for a nuclear protein with 5 C2H2-type zinc finger domains. The protein is expressed early in embryogenesis and plays a critical role as both a repressor and activator of transcription. Human GLIS3 mutations are extremely rare. OBJECTIVE: The purpose of this article was determine the phenotypic presentation of 12 patients with a variety of GLIS3 mutations. METHODS: GLIS3 gene mutations were sought by PCR amplification and sequence analysis of exons 1 to 11. Clinical information was provided by the referring clinicians and subsequently using a questionnaire circulated to gain further information. RESULTS: We report the first case of a patient with a compound heterozygous mutation in GLIS3 who did not present with congenital hypothyroidism. All patients presented with neonatal diabetes with a range of insulin sensitivities. Thyroid disease varied among patients. Hepatic and renal disease was common with liver dysfunction ranging from hepatitis to cirrhosis; cystic dysplasia was the most common renal manifestation. We describe new presenting features in patients with GLIS3 mutations, including craniosynostosis, hiatus hernia, atrial septal defect, splenic cyst, and choanal atresia and confirm further cases with sensorineural deafness and exocrine pancreatic insufficiency. CONCLUSION: We report new findings within the GLIS3 phenotype, further extending the spectrum of abnormalities associated with GLIS3 mutations and providing novel insights into the role of GLIS3 in human physiological development. All but 2 of the patients within our cohort are still alive, and we describe the first patient to live to adulthood with a GLIS3 mutation, suggesting that even patients with a severe GLIS3 phenotype may have a longer life expectancy than originally described.


Assuntos
Doenças Ósseas/genética , Hipotireoidismo Congênito/genética , Deficiências do Desenvolvimento/genética , Diabetes Mellitus/genética , Resistência à Insulina/genética , Hepatopatias/genética , Fenótipo , Fatores de Transcrição/genética , Doenças Ósseas/congênito , Proteínas de Ligação a DNA , Diabetes Mellitus/congênito , Feminino , Humanos , Lactente , Recém-Nascido , Hepatopatias/congênito , Masculino , Proteínas Repressoras , Transativadores
9.
J Interferon Cytokine Res ; 20(2): 187-90, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10714554

RESUMO

Recent studies have shown that loci outside the HLA region are involved in determining susceptibility to type 1 diabetes. Polymorphisms in the coding and noncoding regions of the genes encoding cytokines may be involved in modulating the immune response to self and nonself antigens. There is increasing evidence that an imbalance and disruption of the Thl and Th2 T cell subsets play a key role in the development of experimental and clinical type 1 diabetes. The aim of this study was to investigate the frequency of a CA dinucleotide repeat polymorphism in the interferon-gamma (IFN-gamma) gene (IFNG) and a C(-590)T polymorphism of the interleukin-4 (IL-4) gene in 236 Caucasoid patients with type 1 diabetes. There was a highly significant increase in the 3/3 IFNG genotype in the patients compared with normal healthy controls (34.3% vs. 13.5%, p<0.0001) as well as a significant increase in allele 3 of the IFNG locus in the patients compared with controls (51.9% vs. 31.7%, p<0.00001). In contrast, no significant differences were found in the frequency of the C(-590)T IL-4 polymorphism between patients and controls. These results suggest that polymorphisms of the IFNG gene may modify the function of this proinflammatory mediator and the response to pancreatic islet beta cells.


Assuntos
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Repetições de Dinucleotídeos , Interferon gama/genética , Polimorfismo Genético , Adolescente , Adulto , Alelos , Sequência de Bases , Estudos de Casos e Controles , Criança , Primers do DNA/genética , Feminino , Frequência do Gene , Humanos , Recém-Nascido , Interleucina-4/genética , Ilhotas Pancreáticas/imunologia , Masculino , Pessoa de Meia-Idade , Gravidez , Tolerância a Antígenos Próprios/genética
10.
Invest Ophthalmol Vis Sci ; 41(13): 4064-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11095596

RESUMO

PURPOSE: Aldose reductase (ALR2) is the first and rate-limiting enzyme of the polyol pathway and is involved in the pathogenesis of diabetic retinopathy. Polymorphisms of the ALR2 gene are associated with susceptibility to diabetic retinopathy in Chinese and Japanese patients with type 2 diabetes. There are no reports investigating these polymorphisms in white patients with type 1 diabetes from either Western Europe or North America. A CA dinucleotide repeat polymorphism (5'ALR2; located at -2100 bp) as well as a novel C(106)T polymorphism was investigated in 229 white patients with type 1 diabetes, with or without retinopathy. METHODS: The DNA was typed for these polymorphisms using conventional polymerase chain reaction techniques. RESULTS: There was a highly significant increase in the frequency of the Z-2 5'ALR2 allele and Z-2/X (where X is not Z+2) genotype in patients with diabetic retinopathy (n = 159) compared with those without who had diabetes of 20 years' duration (uncomplicated, n = 70; chi(2) = 17.0, P < 0.0001). There was a similar decrease in the Z+2/Y genotype (where Y is not Z-2; chi(2) = 30.1, P < 0.000,001) in the patients with retinopathy compared with the uncomplicated diabetes group. The C/Z-2 C(-106)T/5' ALR2 haplotype was found in 33.3% of the patients with retinopathy and 8.7% of the patients with uncomplicated diabetes. CONCLUSIONS: These results confirm previous studies in other populations and in type 2 diabetes showing that polymorphisms in the promoter region of the ALR2 gene are associated with susceptibility to diabetic retinopathy.


Assuntos
Aldeído Redutase/genética , Diabetes Mellitus Tipo 1/genética , Retinopatia Diabética/genética , Predisposição Genética para Doença , Polimorfismo Genético , Adolescente , Adulto , Idoso , Alelos , Criança , Pré-Escolar , DNA/análise , Diabetes Mellitus Tipo 1/enzimologia , Retinopatia Diabética/enzimologia , Feminino , Frequência do Gene , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
11.
Autoimmunity ; 18(1): 77-83, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7999959

RESUMO

Type I diabetes is an autoimmune disease characterised by a marked activation of peripheral T cells around the time of clinical diagnosis. Studies of T-cell antigen receptor V beta (TCRBV) gene usage in type I diabetes have been conflicting. Using a semi-quantitative polymerase chain reaction technique and flow cytometry we have investigated the TCRBV gene usage of 13 newly diagnosed patients with type I diabetes and 11 normal healthy controls. No preferential TCRBV gene usage was found between patients and controls even after matching for HLA-DR3 and/or -DR4. In addition, no significant differences in TCRBV gene usage were found between sequential samples taken over a period of up to 7 months following diagnosis. These results suggest that the TCR repertoire of these patients is heterogeneous and it is unlikely that a single 'pathogenic' T-cell clone is dominant at the clinical onset of the disease.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Antígenos HLA-DR/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Reação em Cadeia da Polimerase
16.
J Sports Sci ; 5(2): 93-103, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3441021

RESUMO

A model of the motion of a single-scull rowing hull has been developed and verified against rowing performance data. The model was then used to explore the effect of changes in the cyclic rowing force on the boat speed. The calculations have shown that the shape of the rowing force curve and the proportion of recovery time in the total stroke can have an important effect on the boat speed. It has also been shown that a study of the fluid mechanics of the oar blade would be advantageous in determining whether a reduction in the power wasted can be obtained by changing the ratio of rowing force to normal force.


Assuntos
Modelos Teóricos , Esportes , Engenharia , Matemática , Fenômenos Físicos , Física
17.
Soc Work Health Care ; 34(3-4): 241-59, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12243427

RESUMO

This paper examines the establishment of social work within primary health care settings in Great Britain, following the passage of the National Health Service and Community Care Act in 1990. Although the improvement of relationships between social workers and primary health care teams has been promoted for a number of years, the advent of formal policies for community care has made this a priority for both social services and health. This paper presents interim findings from the evaluation of three pilot projects in Nottinghamshire, Great Britain. These findings are analysed from three linked perspectives. The first is the extent to which structures and organisations have worked effectively together to promote the location of social workers within health care settings. The second is the impact of professional and cultural factors on the work of the social worker in these settings. The third is the effect of interpersonal relationships on the success of the project. The paper will conclude that there is significant learning from each of these perspectives which can be applied to the future location of social workers to primary health care.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Atenção Primária à Saúde/organização & administração , Serviço Social/organização & administração , Humanos , Relações Interprofissionais , Cultura Organizacional , Avaliação de Programas e Projetos de Saúde , Reino Unido
18.
ASDC J Dent Child ; 61(4): 263-6, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7989629

RESUMO

Although there is very little epidemiological evidence on the prevalence and severity of erosion in children and adults, there have been recent case reports suggesting that the problem of erosion is increasing. This study describes the use of a simple reproducible erosion index. A total of 178 four-year-old children were assessed; almost half of these children showed signs of erosion. The most common site affected was the palatal surface of the upper incisors with 17 percent of the children examined showing visible dentine for greater than one third of the tooth surface. When considering the influence of socioeconomic group on the prevalence of erosion, four out of five children examined in the low socioeconomic group showed low levels of erosion, while a much greater prevalence was observed in the higher socioeconomic groups.


Assuntos
Erosão Dentária/epidemiologia , Distribuição de Qui-Quadrado , Pré-Escolar , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Prevalência , Reprodutibilidade dos Testes , Classe Social , Estatísticas não Paramétricas , Erosão Dentária/diagnóstico , Dente Decíduo
19.
J Environ Manage ; 61(4): 329-43, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11383105

RESUMO

This research demonstrates the predictive modeling capabilities of a geographic information system (GIS)-based soil erosion potential model to assess the effects of implementing land use change within a tropical watershed. The Revised Universal Soil Loss Equation (RUSLE) was integrated with a GIS to produce an Erosion Prediction Information System (EPIS) and modified to reflect conditions found in the mountainous tropics. Research was conducted in the Zenzontia subcatchment of the Río Ayuquíla, located within the Sierra de Manantlán Biosphere Reserve (SMBR), México. Expanding agricultural activities within this area will accentuate the already high rate of soil erosion and resultant sediment loading occurring in the Río Ayuquíla. Two land-use change scenarios are modeled with the EPIS: (1) implementation of soil conservation practices in erosion prone locations; and (2) selection of sites for agricultural expansion which minimize potential soil loss. Confronted with limited financial resources and the necessity for expedient action, managers of the SMBR can draw upon the predictive capacity of the EPIS to facilitate rapid and informed land-use planning decisions.


Assuntos
Conservação dos Recursos Naturais , Sistemas de Informação , Modelos Teóricos , Solo , Agricultura , Tomada de Decisões , Geografia
20.
J Oral Rehabil ; 22(1): 37-42, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7897557

RESUMO

An in vitro experimental model has been developed for erosive lesion formation in dental enamel which can mimic in vivo conditions at the tooth surface. The features of this model provide a very reproducible method of producing erosive lesions in several teeth under identical conditions which can be varied to allow examination of a number of different parameters. A replica impression technique has also been developed for subsequent non-destructive microscopic examination of the lesions and comparison with in vivo lesions.


Assuntos
Erosão Dentária/patologia , Resinas Acrílicas , Citratos/farmacologia , Ácido Cítrico , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/patologia , Esmalte Dentário/ultraestrutura , Materiais para Moldagem Odontológica , Liofilização , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Polivinil , Técnicas de Réplica , Siloxanas , Erosão Dentária/induzido quimicamente
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