Rhus semialata M. extract ameliorate para-phenylenediamine-induced toxicity in keratinocytes.

para-Phenylediamine (PPD), a major component of hair dyeing ingredients, can induce allergenic sensitization and exert mutagenic, tumorigenic and cytotoxic effect. In this study, we determined the cytotoxic effect of PPD on human keratinocytes and evaluated the protective effect of Rhus semialata M. extracts (RSE) on PPD induced cytotoxicity for the first time. We observed that RSE is a strong inhibitory agent against PPD-induced toxicity in human keratinocytes. The results indicated that RSE pretreatment significantly could suppress PPD induced cytotoxic effects, including decrease of cell viability, accumulation in subG1 phase of cells, and relocation of phosphatidylserine on keratinocytes. Also, we found that PPD caused cytotoxicity was associated with mitochondrial membrane potential loss and subsequent activation of caspase and PARP degradation. However, pretreatment of RSE showed preventive activities against PPD induced mitochondrial membrane potential loss and ROS production in keratinocytes. In conclusion, the results of present study suggest that RSE was able to protect the skin from several cytotoxic effects of PPD and could be a meaningful material in many industries using PPD.

Length and sequence effect on the B-Z transition of [d(A-T)n]2 oligonucleotide induced by a cationic porphyrin.

trans-BMPyP induced the B-Z transition for alternated AT oligonucleotides as it was evident by inversed CD spectrum. The transition occurred simultaneously with appearance of the extensive stacking of porphyrin. Complete B-Z transition required at least 14 base-pairs long. Insertion of one or two GC base pairs prevented the B-Z transition.

Cochlear implantation after bilateral transverse temporal bone fractures.

Patients deafened by a severe head injury are rarely encountered. We report a case of a 65-yr-old man with bilateral transverse temporal bone fractures due to head injury. He underwent cochlear implant and achieved a satisfactory auditory rehabilitation. Imaging studies of temporal bone before performing a cochlear implantation provide important information on a patient with bilateral temporal bone fractures. Cochlear implantations with careful planning in such a patient may be a very effective method for aural rehabilitation.

A case of unilateral sensorineural hearing loss caused by a venous malformation of the internal auditory canal.

Intracranial vascular malformations can be classified as telangiectasis, varices, cavernous malformations, venous malformations (VMs), or arteriovenous malformations. VMs are congenital vascular malformations of the brain thought to be anomalies of the normal venous drainage. VMs are the most common intracranial vascular malformations documented by brain imaging and by autopsy series. However, vascular lesions of the internal auditory canal (IAC) are extremely rare. We report here a case of a VM arising within the IAC and expanding to the brainstem, causing a unilateral profound sensorineural hearing loss (SNHL). To the best of our knowledge, this is the first documented case of a VM as a rare cause of a unilateral SNHL in a child.