Effect of Sodium Silicate on Hair Growth in C57BL/6 Mice / 한국실험동물학회지

A promoting effect of Na2SiO3 on hair regrowth was investigated using an animal model of C57BL/6 mice. There were four experimental groups including distilled water (DW, a negative control), 5% minoxidil (MXD, a positive control), 50% Na2SiO3, and 100% Na2SiO3 solution. The animals were shaved with an electric clipper and then test solutions applied daily with a volume of 0.2 ml per to the dorsal skin of mice for 3 weeks. Body weight and food and water consumption were measured weekly. Photographs of hair regrowth were taken at experimental day 0, 4, 7, 10, 14, 17, and 21. Activities of alkaline phosphatase and gamma-glutamyl transpeptidase as well as expressions of growth factors were also determined in the dorsal skin of mice. The animal body weight were not significantly changed among the experimental groups. The MXD and Na2SiO3 accelerated hair regrowth compared with DW. The elongation of hair follicles were evidently observed in MXD and 50 or 100% Na2SiO3 groups. MXD significantly increased gamma-glutamyl transpeptidase at day 14, compared with DW (P<0.05). But the activities of alkaline phosphatase and gamma-glutamyl transpeptidase were not significantly increased in Na2SiO3 groups, compared with DW. The expression of epidermal growth factor was significantly increased in MXD and Na2SiO3 groups, compared with DW (P<0.05). The expression of vascular endothelial growth factor was not significantly changed by MXD or Na2SiO3 treatments. The expression of transforming growth factor (TGF)-beta1 was clearly decreased in MXD and Na2SiO3 groups, compared with DW. These results indicate that Na2SiO3 may have a hair growth-promoting activity and it can be used for treatment of alopecia or boldness in humans.

Evaluation of Dipicolinic Acid-Based Mueller Hinton Agar Biplate for Detection of IMP-1 and VIM-2 type Metallo-beta-Lactamase in Imipenem Non-susceptible Gram Negative Bacilli / 대한진단검사의학회지

BACKGROUND: Since metallo-beta-lactamase (MBL)-producing isolates can hydrolyze carbapenem and also easily transfer the resistance genes to other bacteria, a rapid and accurate detection of MBL has become very important. We evaluated the utility of Mueller Hinton agar (MHA) biplate containing dipicolinic acid (DPA) as a screening method to detect IMP-1 and VIM-2 type MBL-producing isolates. METHODS: Based on our preliminary tests using various concentrations of DPA, 200 and 300 microg/mL concentration of DPA were chosen for further study. Bacterial lawns were grown on MHA biplate, one half of which contained DPA while the other did not. The inhibition zone around the imipenem (IPM) disk on both sides of this plate was compared. The stability of DPA in the stored DPA-MHA biplate was also evaluated during three months using two MBL- and one non-MBL-producing isolates. RESULTS: When the criterion of a > or =7 mm increase of inhibition zone around the IPM disk on the MHA containing DPA compared to MHA without DPA was used, the sensitivities and specificities were 94.7% and 97.6% for 200 microg/mL DPA-MHA biplate, and 98.2% and 97.6% for 300 microg/mL DPA-MHA biplate, respectively. The activity of the DPA in this biplate was stable for three months. CONCLUSIONS: Assays using DPA 300-MHA biplate were highly sensitive and specific for the detection of IMP-1 and VIM-2 type MBL-producing bacteria. In addition, it is easy to perform; so, it may be useful to apply this method for detection of IMP-1 and VIM-2 type MBL in clinical laboratories.