Low-Intensity Laser Irradiation Stimulates Bone Nodule Formation Via Insulin-Like Growth Factor-I Expression in Rat Calvarial Cells

Low-Intensity Laser Irradiation Stimulates Bone Nodule Formation Via Insulin-Like Growth Factor-I Expression in Rat Calvarial Cells

Noriyoshi Shimizu, Kotoe Mayahara, Takeshi Kiyosaki,

Akikuni Yamaguchi, Yasuhiro Ozawa, Yoshimitsu Abiko

Background and Objective: We previously reported that low-intensity laser irradiation stimulated bone nodule formation through enhanced cellular proliferation and differentiation. However, the mechanisms of irradiation are unclear. Thus, we attempted to determine the responsibility of insulin-like growth factor (IGF)-I for the action observed.

Study Design/Materials and Methods: Osteoblast-like cells were isolated from fetal rat calvariae and cultured with rat recombinant (r) IGF-I, IGF-I antibody (Ab), and/or the cells were irradiated once (3.75 J/cm2) with a low-intensity Ga-Al-As laser (830 nm). The number and area of bone nodules formed in the culture were analyzed, and IGF-I expression was also examined.

Results: Treatment with rIGF-I significantly stimulated the number and area of bone nodules. This stimulatory effect was quite similar to those by laser irradiation, and this stimulation was abrogated dose-dependently by treatment with IGF-I-Ab. Moreover, laser irradiation significantly increased IGF-I protein and gene expression.

Conclusion: The stimulatory effect of bone nodule formation by low-intensity laser irradiation will be at least partly mediated by IGF-I expression. Lasers Surg. Med. 39:551-559, 2007. © 2007 Wiley-Liss, Inc.

Key words: low-intensity laserl bone formation; IGF-I; bone nodule; calvarial cell; osteoblast

dysphagia- aftter stroke

Next week will be : Mr A

Dysphagia- Chapter

Mr S. 78 y. o

Chief complaint: difficulty of swallow




Anamnesis: liguid, semisolid , easy to swallow
could'not swallow medicine by water


Picture above: thick, not clean (Stroke?)


CT scan, MRI : non stroke

Feeding habit: every meal served after blend= semisolid





Physical examination:
- oral : gag refleks good
- oromotor : good
- all reflects : good


Solution: I asked him to chew a bite of fruit as exercise, at least an apple a day.


Picture below: a week after --> excellent!

So, use it , or lose it !!!!

Low level laser for vertigo and snoring

I had a patient, came due to her vertigo. I gave 10 times low level laser. It was amazing ! Her balance improved, as well as her hearing loss. Diabetic is her underlying disease .

A man 54 y.o came due to hearing loss. his regiment didn't finish yet, but the good point: his wife told us: He is not snoring again !

Visit again , I'l report those two cases and update Henny (dysphoni).