ABSTRACT
Abstract This paper focuses on geneticists Salvador Armendares's and Rubén Lisker's studies from the 1960s to the 1980s, to explore how their work fits into the post-1945 human biological studies, and also how the populations they studied, child and indigenous, can be considered laboratories of knowledge production. This paper describes how populations were considered for different purposes: scientific inquiry, standardization of medical practices, and production or application of medicines. Through the narrative of the different trajectories and collaborations between Armendares and Lisker, this paper also attempts to show the contact of their scientific practices, which brought cytogenetics and population genetics together at the local and global levels from a transnational perspective.
Resumo Aborda o trabalho dos geneticistas Salvador Armendares e Rubén Lisker, entre 1960 e 1980, para analisar como se insere nos estudos biológicos humanos do pós-1945, e demonstra como as populações estudadas por eles, a infantil e a indígena, podem ser consideradas laboratórios de produção de conhecimento. O artigo revela como as populações foram consideradas para diversos propósitos: investigação científica, padronização das práticas médicas e produção ou aplicação de suas medicinas. Por meio da narrativa das diferentes trajetórias e colaborações entre Armendares e Lisker, também procura discutir o contato de suas práticas científicas, que colocaram a citogenética e a genética de populações lado a lado nos níveis local e global a partir de uma perspectiva transnacional.
Subject(s)
Humans , Child , History, 20th Century , Human Genetics/history , Indigenous Peoples/history , Genetics, Population/history , Carbohydrate Metabolism, Inborn Errors/history , Cytogenetics/history , Lactase/deficiency , Lactase/history , Indigenous Peoples/genetics , Glucosephosphate Dehydrogenase Deficiency/history , Karyotyping/history , MexicoABSTRACT
ABSTRACT Background Primary hypolactasia is a common condition where a reduced lactase activity in the intestinal mucosa is present. The presence of abdominal symptoms due to poor absorption of lactose, which are present in some cases, is a characteristic of lactose intolerance. , Objective Evaluate the efficacy of a product containing exogenous lactase in tablet form compared to a reference product with proven effectiveness in patients with lactose intolerance. Methods Multicentre, randomized, parallel group, single-blind, comparative non-inferiority study. One hundred twenty-nine (129) adult lactose intolerance patients with hydrogen breath test results consistent with a diagnosis of hypolactasia were randomly assigned to receive the experimental product (Perlatte(r) - Eurofarma Laboratórios S.A.) or the reference product (Lactaid(r) - McNeilNutritionals, USA) orally (one tablet, three times per day) for 42 consecutive days. Results Data from 128 patients who actually received the studied treatments were analysed (66 were treated with the experimental product and 62 with the reference product). The two groups presented with similar baseline clinical and demographic data. Mean exhaled hydrogen concentration tested at 90 minutes after the last treatment (Day 42) was significantly lower in the experimental product treated group (17±18 ppm versus 34±47 ppm) in the per protocol population. The difference between the means of the two groups was -17 ppm (95% confidence interval [95% CI]: -31.03; -3.17). The upper limit of the 95% CI did not exceed the a priori non-inferiority limit (7.5 ppm). Secondary efficacy analyses confirmed that the treatments were similar (per protocol and intention to treat population). The tolerability was excellent in both groups, and there were no reports of serious adverse events related to the study treatment. Conclusion The experimental product was non-inferior to the reference product, indicating that it was an effective replacement therapy for endogenous lactase in lactose intolerance patients.
RESUMO Contexto A hipolactasia primária é uma condição muito frequente na qual há redução da atividade da lactase na mucosa intestinal.A presença de sintomas abdominais devidos à má absorção da lactose presente em alguns casos caracteriza a intolerância à lactose. Objetivo Avaliar a eficácia de um produto contendo lactase exógena em comprimidos comparativamente a de um produto comparador com eficácia comprovada em pacientes portadores de intolerância à lactose. Métodos Estudo multicêntrico, randomizado, de grupos paralelos, com investigador cego, comparativo de não-inferioridade. Cento e vinte e nove (129) pacientes adultos portadores de intolerância à lactose e teste do hidrogênio no ar expirado compatível com o diagnóstico de hipolactasia foram randomizados para receber o produto experimental (Perlatte(r) - Eurofarma Laboratórios S.A.) ou o produto comparador (Lactaid(r) - McNeil Nutritionals, EUA), por via oral (um comprimido, três vezes ao dia), durante 42 dias consecutivos. Resultados Os dados dos 128 pacientes que efetivamente receberam o tratamento do estudo foram avaliados (66 tratados com o produto experimental e 62 com o produto comparador). Os dois grupos se mostraram homogêneos quanto aos dados demográficos e clínicos basais. A média da concentração do hidrogênio expirado aos 90 minutos no teste realizado ao final do tratamento (Dia 42) foi significativamente menor no grupo tratado com o produto experimental (17±18 ppm versus 34±47 ppm na população por protocolo). A diferença entre as médias dos dois grupos foi de -17 ppm (intervalo de confiança de 95% [IC95%]: -31,03; -3,17). O limite superior do IC95% não ultrapassou a margem de não-inferioridade estipulada a priori (7,5 ppm). As análises secundárias de eficácia confirmaram a semelhança entre os tratamentos (populações por protocolo e com intenção de tratamento). A tolerabilidade foi excelente em ambos os grupos e não houve relato de eventos adversos graves relacionados ao produto. Conclusão O produto experimental se mostrou não-inferior ao produto comparador, indicando sua eficácia no tratamento substitutivo da lactase endógena em pacientes portadores de intolerância à lactose.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Young Adult , Lactase/administration & dosage , Lactase/deficiency , Lactose Intolerance/drug therapy , Single-Blind Method , Administration, Oral , Treatment Outcome , Hydrogen/analysis , Lactose/metabolism , Lactose Intolerance/diagnosis , Middle AgedABSTRACT
PURPOSE: To analyze the usefulness of Quick Lactose Intolerance Test in relation to the genetic test based on LCT-13910C>T genotypes, previously validated for clinical practice, for primary hypolactasia/lactase-persistence diagnosis. METHODS: Thirty-two dyspeptic patients that underwent upper gastrointestinal endoscopy entered the study. Two postbulbar duodenal biopsies were taken for the Quick test, and gastric antral biopsy for DNA extraction and LCT-13910C>T polymorphism analysis. DNA was also extracted from biopsies after being used in the Quick Test that was kept frozen until extraction. RESULTS: Nine patients with lactase-persistence genotype (LCT-13910CT or LCT-13910TT) had normolactasia, eleven patients with hypolactasia genotype (LCT-13910CC) had severe hypolactasia, and among twelve with mild hypolactasia, except for one that had LCT-13910CT genotype, all the others had hypolactasia genotype. The agreement between genetic test and quick test was high (p<0.0001; Kappa Index 0.92). Most of the patients that reported symptoms with lactose-containing food ingestion had severe hypolactasia (p<0.05). Amplification with good quality PCR product was also obtained with DNA extracted from biopsies previously used in the Quick Test; thus, for the future studies antral gastric biopsies for genetic test would be unnecessary. CONCLUSION: Quick test is highly sensitive and specific for hypolactasia diagnosis and indicated those patients with symptoms of lactose intolerance.
OBJETIVO: Analisar a aplicabilidade do Teste Quick de Intolerância à Lactose em relação ao teste genético baseado nos genótipos LCT-13910C>T, previamente validado para a prática clínica, para diagnóstico de má digestão primária de lactose/digestão de lactose. MÉTODOS: Trinta e dois pacientes dispépticos submetidos à endoscopia digestiva entraram no estudo. Duas biópsias duodenais pós-bulbares foram empregadas no Teste Quick, e biópsia do antro gástrico para extração de DNA e análise do polimorfismo LCT-13910C>T. DNA também foi extraído de biópsias depois de terem sido usadas no teste Quick, e conservadas congeladas. RESULTADOS: Nove pacientes com genótipo de lactase persistente (LCT-13910CT ou LCT-13910TT) tinham normolactasia, onze pacientes com genótipo de hipolactasia (LCT-13910CC) tinham hipolactasia severa, e entre doze com hipolactasia leve, com exceção de uma que tinha genótipo LCT-13910CT, todos os demais tinham genótipo de hipolactasia. A concordância entre o teste genético e o Quick Teste foi alta (p<0,0001; Índice Kappa=0,92). A maioria dos pacientes que relataram sintomas com ingestão de alimentos com lactose tinham hipolactasia severa (p<0,05). Amplificação com produto de PCR foi obtido com DNA extraído das biópsias usadas no teste Quick; portanto, nos trabalhos futuros seria desnecessário coletar biópsia do antro gástrico para o teste genético. CONCLUSÃO: O Teste Quick é altamente sensível e específico para diagnóstico de hipolactasia e indicou aqueles pacientes com sintomas de intolerância à lactose.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Genetic Testing , Lactose Intolerance/diagnosis , Lactose Tolerance Test/methods , Biopsy , Duodenum/pathology , Dyspepsia/pathology , Endoscopes, Gastrointestinal , Genotype , Lactase/deficiency , Lactose Intolerance/genetics , Lactose/genetics , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Prothrombin Time , Retrospective Studies , Surveys and QuestionnairesABSTRACT
BACKGROUND & OBJECTIVES: Prevalence of adult-type hypolactasia is known to vary among different countries and in different ethnic populations in the same country. The present study was undertaken to evaluate the prevalence of hypolactasia and lactose intolerance in three different ethnic populations living in similar environmental conditions in Malaysia. The correlation between different symptoms and lactose intolerance test was also studied. METHODS: A total of 300 Malaysian subjects from three different ethnic populations: Malays, Chinese and Indians (100 volunteers in each group, 18-49 yr old working or studying in a University) were included. Urine galactose excretion and gastrointestinal symptoms were measured after lactose intake (50 g). RESULTS: Based on galactose excretion, 88 per cent of the Malays, 91 per cent of the Chinese and 83 per cent of the Indians were hypolactasic. The differences were statistically not significant. When the symptoms were also considered, prevalence of lactose intolerance appeared to be significantly lowest among the Indians. When the subjects were divided into low, middle and high galactose excretion groups some correlation was found between the symptoms and galactose excretion. INTERPRETATION & CONCLUSION: There was no clear association between hypolactasia and gastrointestinal symptoms in all the study groups. However, the lactose intolerance was high in all the study groups indicating the increasing demand for low lactose dairy products in the Asian countries.