Allelic variants of the tryptophan hydroxylase (A218C) and serotonin 1B receptor (A-161T) and personality traits

Human personality traits have a considerable hereditary component, and central serotonergic activity is implicated in the personality factors of the Tridimensional Personality Questionnaire (TPQ). Our population-based association study tested the hypothesis that the tryptophan hydroxylase (TPH) A218C and serotonin 1B receptor (HTR1B) A-161T polymorphisms were associated with TPQ personality trait scores in a sample population of 209 young healthy Chinese. No significant differences were demonstrated comparing scores of subjects bearing different TPH or HTR1B genotypes; however, a trend for difference in the novelty seeking score comparing TPH genotype groups was determined for the male population. Our negative findings suggest that the TPH A218C and HTR1B polymorphisms do not play major roles in the determination of TPQ personality traits.     

Early embryonic death of glutamate carboxypeptidase II (NAALADase) homozygous mutants

Glutamate carboxypeptidase II (EC 3.4.17.21) catalyzes the hydrolysis (Km = 0.2 microM) of the neuropeptide N-acetylaspartylglutamate to yield N-acetylaspartate and glutamate and also serves as a high-affinity folate hydrolase in the gut, cleaving the polyglutamate chain to permit the absorption of folate. N-acetylaspartylglutamate is an agonist at the mGluR3 metabotropic receptor and a source of extracellular glutamate through hydrolysis by glutamate carboxypeptidase II. Given the important role of glutamate in brain development and function, we were interested in the effects of a null mutation of glutamate carboxypeptidase II that would potentiate the effects of N-acetylaspartylglutamate. The PGK-Neomycin cassette was inserted to delete exons 9 and 10, which we previously demonstrated encode for the zinc ligand domain essential for enzyme activity. Successful germline transmission was obtained from chimeras derived from embryonic stem cells with the targeted mutation of glutamate carboxypeptidase II. Homozygous null mutants did not survive beyond embryonic day 8. Folate supplementation of the heterozygous mothers did not rescue the homozygous embryos. Mice heterozygous for the null mutation appeared grossly normal and expressed both mutated and wild-type mRNA but the activity of glutamate carboxypeptidase II is comparable to the wild-type mice. The results indicate that the expression of glutamate carboxypeptidase II is upregulated when one allele is inactivated and that its activity is essential for early embryogenesis.     

Diabetes and idiopathic cardiomyopathy: a nationwide case-control study

OBJECTIVE: Controversy exists regarding the relation between diabetes and nonischemic idiopathic cardiomyopathy (ICM), and only limited data on the incidence of ICM in adults with diabetes are available. Therefore, we used the 1995 Nationwide Inpatient Sample (NIS) to determine discharge rates and test the hypothesis that diabetes is independently associated with ICM. RESEARCH DESIGN AND METHODS: The 1995 NIS includes demographic and diagnostic data on all discharges from >900 representative hospitals in 19 states. ICD-9 codes were used to identify ICM, defined as discharges with a diagnosis of primary cardiomyopathy but without established risk factors for cardiomyopathy. Control subjects were selected by stratified random sampling by age to yield 10 per ICM case. The analyzed covariates included age, race, median income, diabetes, and hypertension. Multivariate logistic regression was used to conduct case-control analyses. RESULTS: Using sampling weights, we estimated that in 1995, the rate of hospital discharge for ICM among individuals diagnosed with diabetes was 7.6 per 1000. The prevalence of diabetes was substantially higher in the 44837 ICM vs. 450254 control subjects (26.6 vs. 17.2%), corresponding to a relative odds (RO) of 1.75 (95% CI 1.71-1.79). After adjusting for age, sex, race, hypertension, and median income using multiple logistic regression, diabetes remained significantly associated with ICM (RO 1.58, 95% CI 1.55-1.62). CONCLUSIONS: We concluded that diabetes is independently associated with ICM in the general U.S. population.     

Choanal atresia: an unusual serious complication of complementary and alternative medical treatment

The use of complementary and alternative medicine (CAM) is common among patients with chronic, long-standing nasal disease. Complications resulting from inappropriate CAM practices are sometimes reported, but serious complications such as choanal atresia and stenosis are rare. We report a case of choanal atresia and stenosis due to herbal drug (ie, chemical) cauterization of the nasal cavity in a 39-year-old man. We reviewed the literature on why patients previously given conventional treatment seek alternative therapies. The patient underwent surgical intervention to relieve choanal atresia and stenosis. The postoperative course was unremarkable, and follow-up for 1 year revealed no evidence of restenosis. Choanal atresia and stenosis resulting from CAM treatment are rare. Otolaryngologists should be aware of possible complications occurring in patients receiving such treatments.     

Management of talon cusp affecting the primary central incisor: a case report

Talon cusps are relatively rare dental anomalies that manifest as accessory cusplike structures and project from the cingulum area of the anterior teeth. The condition can occur in both the primary and permanent dentitions. However, the occurrences of anomalous cusps are rather infrequent in the primary dentition. Little has been written about the treatment of talon cusps in the primary dentition compared with their counterparts in the permanent dentition. The purpose of this article was to document the management of a patient with a maxillary primary incisor affected by a talon cusp and the long-term follow up.