Effect of genetic polymorphisms rs2301113 and rs2057482 in the expression of HIF-1α protein in periodontal ligament fibroblasts subjected to compressive force

Abstract Objective Many genes and signaling molecules are involved in orthodontic tooth movement, with mechanically and hypoxically stabilized HIF-1α having been shown to play a decisive role in periodontal ligament signaling during orthodontic tooth movement. Thus, this in vitro study aimed to investigate if genetic polymorphisms in HIF1A (Hypoxia-inducible factor α-subunits) influence the expression pattern of HIF-1α protein during simulated orthodontic compressive pressure. Methodology Samples from human periodontal ligament fibroblasts were used and their DNA was genotyped using real time Polymerase chain reaction for the genetic polymorphisms rs2301113 and rs2057482 in HIF1A . For cell culture and protein expression experiments, six human periodontal ligament fibroblast cell lines were selected based on the patients' genotype. To simulate orthodontic compressive pressure in fibroblasts, a 2 g/cm2 force was applied under cell culture conditions for 48 hours. Protein expression was evaluated by Western Blot. Paired t-tests were used to compare HIF-1α expression with and without compressive pressure application and unpaired t-tests were used to compare expression between the genotypes in rs2057482 and rs2301113 (p<0.05). Results The expression of HIF-1α protein was significantly enhanced by compressive pressure application regardless of the genotype (p<0.0001). The genotypes in the genetic polymorphisms rs2301113 and rs2057482 were not associated with HIF-1α protein expression (p>0.05). Conclusions Our study confirms that compressive pressure application enhances HIF-1α protein expression. We could not prove that the genetic polymorphisms in HIF1A affect HIF-1α protein expression by periodontal ligament fibroblasts during simulated orthodontic compressive force.

Single Nucleotides Polymorphisms in COX2 Gene and their Association with Signs and Symptoms of Teething - A Pilot Study

ABSTRACT Objective: To investigate the association between single nucleotide polymorphisms in the COX2 gene (rs689466 and rs5275) and local and systemic signs and symptoms of teething. Material and Methods: Forty-four pairs of mothers-babies/toddlers were included. Erupted primary teeth were evaluated during clinical examination. Local and systemic signs and symptoms of teething were obtained from mothers' reporting via anamnesis. Samples of buccal cells were retrieved for DNA genotyping using real-time PCR. The T-test, Chi-square test, logistic regression, and haplotype analyses were applied. Results: Almost all mothers (95.5%) reported at least one local or systemic sign and symptom of teething. The most common was increased salivation (79.5%), diarrhea (72.3 %), and fever (70.5 %). The mean number of signs and symptoms per child was higher in boys than girls (mean = 5.1; SD= 1.5; p=0.008). Sleep disturbance (p=0.03) and loss of appetite (p=0.05) were more reported in boys. The rs689466 and rs5275 were not associated with signs and symptoms of teething (p>0.05). Conclusion: The single nucleotide polymorphisms in the COX2 gene (rs689466 and rs5275) were not associated with local and systemic signs and symptoms of teething.

Detecção de encefalopatia hepática mínima através de testes neuropsicológicos e neurofisiológicos e o papel da amônia no seu diagnóstico / Minimal hepatic encephalopathy detection by neuropsychological and neurophysiological methods and the role of ammonia for its diagnosis

CONTEXTO: A encefalopatia hepática mínima vem sendo sistematicamente investigada em pacientes com cirrose hepática. Entretanto, existem controvérsias quanto aos melhores métodos, bem como o papel da amônia para seu diagnóstico. OBJETIVO: Avaliar a frequência de encefalopatia hepática mínima diagnosticada através de testes neuropsicológicos e neurofisiológicos em cirróticos, bem como os possíveis fatores de risco para esta condição, incluindo o papel da concentração arterial de amônia em seu diagnóstico. MÉTODOS: Indivíduos com cirrose hepática foram avaliados através do teste de conexão numérica partes A e B (TCN-A e TCN-B) e potencial evocado relacionado a eventos (P300). O diagnóstico de encefalopatia hepática mínima foi feito quando da presença de anormalidade no P300 e em, pelo menos, um dos testes neuropsicológicos. As concentrações arteriais de amônia, a escolaridade e a gravidade da cirrose hepática também foram avaliadas em todos. RESULTADOS: Foram avaliados 48 pacientes cirróticos, com média de idade 50 ± 8 anos, sendo 79 por cento do sexo masculino. As principais causas foram a alcoólica e a viral. O P300 foi anormal em 75 por cento dos casos e o TCN-A e TCN-B anormais em 58 por cento e 65 por cento dos casos, respectivamente. Os resultados do TCN-B foram influenciados pela escolaridade. A frequência de encefalopatia hepática mínima foi de 50 por cento. A concentração arterial de amônia não foi significantemente maior em pacientes com diagnóstico de encefalopatia hepática mínima (195 ± 152 mmol/L versus 148 ± 146 mmol/L; P>0,05). Não houve diferença significante entre os grupos com e sem encefalopatia hepática mínima quanto às demais variáveis estudadas. CONCLUSÃO:A encefalopatia hepática mínima é condição frequente em pacientes com cirrose hepática. A concentração arterial de amônia não parece ter papel importante no seu diagnóstico.

CONTEXT: Minimal hepatic encephalopathy has been systematically investigated in cirrhotic patients. Although, there are controversies regarding the best methods as well as the role of ammonia for its diagnosis. OBJECTIVE: To evaluate the frequency of minimal hepatic encephalopathy diagnosed by neuropsychological and neurophysiological methods in cirrhotic patients, as well as possible associated risk factors for this condition, including the role of arterial ammonia concentrations for its diagnosis. METHODS: Cirrhotic patients were evaluated by the number connection test parts A and B (NCT-A and NCT-B), and auditory evoked-related potentials (P300). Minimal hepatic encephalopathy was diagnosed by the presence of abnormal P300 and in unless one of the performed neuropsychologic tests. Arterial ammonia concentration, scholarity and cirrhosis severity accessed by Child-Pugh classification were evaluated in all. RESULTS: Forty-eight cirrhotic patients were evaluated, with median age 50 ± 8 years old, 79 percent male. The main etiologies were alcoholic and viral. The P300 was abnormal in 75 percent of cases, while NCT-A and NCT-B were abnormal in 58 percent and 65 percent, respectively. The NCT-B results were influenced by scholarity. The minimal hepatic encephalopathy frequency was 50 percent. Arterial ammonia concentration was not significantly increased in minimal hepatic encephalopathy diagnosed patients (195 ± 152 mmol/L versus 148 ± 146 mmol/L; P>0,05). There was no difference between groups with or without minimal hepatic encephalopathy in the other studied variables. CONCLUSION: Minimal hepatic encephalopathy is a frequent condition in cirrhotic patients. The arterial ammonia concentration does not play a major role in its diagnosis.

Avaliação dos potenciais evocados relacionados a eventos (ERP-P300) em pacientes com cirrose hepática sem encefalopatia / Evaluation of the event-related potential (ERP-P300) in patients with hepatic cirrhosis without encephalopathy

RACIONAL: Na cirrose hepática ocorrem alterações na estrutura do fígado, levando à perda das funções do órgão, com conseqüências neuropsiquiátricas, como disfunções cognitivas. Um dos meios mais efetivos para avaliar objetivamente as funções cognitivas é medir a atividade eletrofisiológica do sistema nervoso central através do potencial evocado relacionado a eventos (ERP-P300). OBJETIVO: Estudar a utilidade do potencial evocado relacionado a eventos (ERP), para avaliar distúrbios cognitivos em pacientes com cirrose hepática e como auxiliar no diagnóstico da encefalopatia hepática mínima. MÉTODO: Foram selecionados 50 pacientes, diagnosticados com cirrose hepática sem sinais clínicos de encefalopatia hepática e 35 voluntários saudáveis de idades e sexo semelhantes. Em todos os pacientes foram realizados exames clínico-neurológico e laboratoriais. Para identificação do prejuízo cognitivo foi utilizado o ERP-P300 e obtida a média da latência da onda P300. RESULTADOS: Houve diferença significativa entre as médias da latência do ERP-P300 do grupo cirrótico e controle. CONCLUSÃO: A realização do ERP-P300 é simples, depende de fatores controláveis de variação e tem fácil reprodutibilidade, podendo ser útil para o rastreio de distúrbios cognitivos em pacientes com cirrose e auxiliar no diagnóstico de encefalopatia hepática mínima.

BACKGROUND: In hepatic cirrhosis structural liver alterations occur leading to the loss of the organ functions with neuro-psychiatric consequence, as cognitive dysfunctions. One of the most effective ways of objectively evaluating cognition is to measure electrophysiological activity in the central nervous system trough event-related potentials (ERP-P300). AIM: To assess the value of the event-related potential (ERP) in order to determine cognitive disturbances in patients with liver cirrhosis and to assist in the diagnosis of minimal hepatic encephalopathy. METHODS: Fifty patients with liver cirrhosis were selected, without clinical symptoms of hepatic encephalopathy and 35 healthy volunteers, matched by sex and age. The patients were submitted to clinical-neurological and laboratorial examination. The ERP-P300 was performed by the two groups to determine cognitive disturbances. RESULTS: The study showed significant differences between the ERP-P300 latency averages of the two groups. CONCLUSION: The ERP-P300 is simple to use and depends on controllable variables. It is also easy to reproduce and, when properly used, can be useful both to determine cognitive disturbances in patients with hepatic cirrhosis and to assist in minimal hepatic encephalopathy diagnosis.