A Homozygous Frameshift Mutation in the HOXC13 Gene Underlies Pure Hair and Nail Ectodermal Dysplasia in a Syrian Family

Pure hair and nail ectodermal dysplasia (PHNED) is a rare genetic disorder characterized by hypotrichosis or complete alopecia, as well as nail dystrophy. Mutations in the type II hair keratin gene KRT85 and the HOXC13 gene on chromosome 12q have recently been identified in families with autosomal‐recessive PHNED. In the present study, we have analyzed a consanguineous Syrian family with an affected girl having complete alopecia and nail dystrophy since birth. The family clearly showed linkage to chromosome 12q13.13–12q14.3, which excluded the KRT85 gene. Sequencing of another candidate gene HOXC13 within the linkage interval identified a homozygous frameshift mutation (c.355delC; p.Leu119Trpfs*20). Expression studies in cultured cells revealed that the mutant HOXC13 protein mislocalized within the cytoplasm, and failed to upregulate the promoter activities of its target genes. Our results strongly suggest crucial roles of the HOXC13 gene in the development of hair and nails in humans.     

Heart failure in hypertensive patients with left ventricular hypertrophy

Left ventricular hypertrophy (LVH) is supposed to be a useful marker of cardiovascular complications during the course of hypertension. Authors compared the presence of heart failure, left ventricular diastolic dysfunction and chronic atrial fibrillation in hypertensive patients with and without left ventricular hypertrophy defined by echocardiography. Hospital records of 192 hypertensives treated in our medical department during years 1996-1999 were analysed. Left ventricular hypertrophy was defined by echocardiography (Penn convention) as left ventricular mass index > 134 g/m2 in men and > 110 g/m2 in women. Presence of LVH was found in 128 patients (mean age 65.9 years), absence of LVH in 64 patients (mean age 64.8 years). Both groups of hypertensives were matched by demographic parameters, by the presence of hyperlipidemia, by smoking habits. Hypertensive patients with left ventricular hypertrophy were more often treated by ACE inhibitors. There were statistically significant more patients with heart failure, left ventricular diastolic dysfunction and chronic atrial fibrillation in LVH-positive patients than in LVH-negative once. There was also statistically significant lower ejection fraction (50.3 +/- 11.4% vs 56.5 +/- 7.4%) in LVH-positive patients than in LVH-negative once. Left ventricular hypertrophy in patients with hypertension brings usually a complicated course of the disease with a high contribution to the development of chronic heart failure.     

Host Genome,Epigenome, and Oral Microbiome Interactions: Toward Personalized Periodontal Therapy

Periodontal diseases are multidimensional and complex. Bacterial content is the initiator, but disease progression depends on genetic and environmental parameters related to the host. Although bone loss magnitude is the common resulting outcome, the biologic process likely represents a unique inflammatory response characteristic to every individual. Therefore, it is obvious that practitioners must take into account the influence of these parameters and tailor a treatment accordingly. New, emerging deoxyribonucleotide‐based technologies allow integration of the biologic impact of the environment, and periodontists should be prepared to incorporate these technologies into their practice to advance personalized medicine. This commentary provides updated insights on the distinctiveness of inflammation per individual in terms of microbiome and genome specificity and cites some educational resources helpful for implementing individualized therapy.     

Obliterative otosclerosis

From January 1990 to December 1996, 293 primary stapedectomies for otosclerosis were performed, among which 14 had obliterative otosclerosis (4.7 per cent). Probability of bilateral obliterative disease was 50 per cent. With this particular condition, a drill-out procedure was used to perform either a stapedectomy or a stapedotomy. In two patients with bilateral 'far-advanced otosclerosis', surgery was effective in enabling the patient to benefit from hearing-aids. In patients with a measurable hearing-loss, an air-bone gap closure to within 10 dB was achieved in 62.5 per cent of the cases and to within 10-20 dB in 37.5 per cent of the cases, with no deterioration of air-conduction thresholds at 8 kHz. A mild sensorineural hearing loss at 4 kHz was observed in 25 per cent of the cases. There was no statistical difference between stapedectomy and stapedotomy. According to these results, the drill-out technique is a safe and effective procedure in cases of obliterative otosclerosis.