TGF-ß and Physiological Root Resorption of Deciduous Teeth.

The present study was performed to examine how transforming growth factor ß (TGF-ß) in root-surrounding tissues on deciduous teeth regulates the differentiation induction into odontoclasts during physiological root resorption. We prepared root-surrounding tissues with (R) or without (N) physiological root resorption scraped off at three regions (R1-R3 or N1-N3) from the cervical area to the apical area of the tooth and measured both TGF-ß and the tartrate-resistant acid phosphatase (TRAP) activities. The TGF-ß activity level was increased in N1-N3, whereas the TRAP activity was increased in R2 and R3. In vitro experiments for the receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-mediated osteoclast differentiation revealed that proteins from N1-N3 and R1-R3 enhanced the TRAP activity in RAW264 cells. A genetic study indicated that the mRNA levels of TGF-ß1 in N1 and N2 were significantly increased, and corresponded with levels of osteoprotegerin (OPG). In contrast, the expression level of RANKL was increased in R2 and R3. Our findings suggest that TGF-ß is closely related to the regulation of OPG induction and RANKL-mediated odontoclast differentiation depending on the timing of RANKL and OPG mRNA expression in the root-surrounding tissues of deciduous teeth during physiological root resorption.

Functions of miR-1 and miR-133a during the postnatal development of masseter and gastrocnemius muscles.

The present study investigated the function of miR-1 and miR-133a during the postnatal development of mouse skeletal muscles. The amounts of miR-1 and miR-133a were measured in mouse masseter and gastrocnemius muscles between 1 and 12 weeks after birth with real-time polymerase chain reaction and those of HDACs, MEF2, MyoD family, MCK, SRF, and Cyclin D1 were measured at 2 and 12 weeks with Western blotting. In both the masseter and gastrocnemius muscles, the amount of miR-1 increased between 1 and 12 weeks, whereas the amount of HADC4 decreased between 2 and 12 weeks. In the masseter muscle, those of MEF2, MyoD, Myogenin, and MCK increased between 2 and 12 weeks, whereas, in the gastrocnemius muscle, only those of MRF4 and MCK increased. The extent of these changes in the masseter muscle was greater than that in the gastrocnemius muscle. The amounts of miR-133a, SRF, and Cyclin D1 did not change significantly in the masseter muscle between 1 and 12 weeks after birth. By contrast, in the gastrocnemius muscle, the amounts of miR-133a and Cyclin D1 increased, whereas that of SRF decreased. Our findings suggest that the regulatory pathway of miR-1 via HDAC4 and MEF2 plays a more prominent role during postnatal development in the masseter muscle than in the gastrocnemius muscle, whereas that of miR-133a via SRF plays a more prominent role in the gastrocnemius muscle than in the masseter muscle.

The characteristics of people requesting HIV antibody tests at public health centers in Japan.

BACKGROUND: The epidemiologic features of those who requested to undergo the human immunodeficiency virus (HIV) antibody test at public health centers in Japan are still ambiguous, although as a group, they are probably at a high risk to be infected. METHODS: Between April 2001 and March 2002, 14,900 persons visited 131 public health centers that cooperated with this study in relation to the HIV antibody tests. A questionnaire was given to 8,972 persons who agreed to participate in the survey and 5,079 (56.6%) returned the form. Excluding those filled out by persons whose true intent in undergoing the test was the diagnosis of hepatitis C, 4,102 questionnaires were analyzed, individual characteristics examined, and first time visitors and repeaters were compared to assess their behavior and the reasons for of undergoing the test. RESULTS: There were 2,515 (61.3%) males and 1,587 (38.7%) females. The largest age group was composed of 25 to 29 year-olds. Repeaters accounted for 27.2% of all the males and 21.3% of all the females. Their main reason for undergoing the test was anxiety about having contracted an HIV infection through sexual contact with a person of the opposite sex. The proportion of those having sexual contact with males was significantly higher among male repeaters (14.1%) than first timers (8.0%). Among females, the proportion of those who had experience of sexual contact with many and unspecified males was significantly higher for repeaters (39.6%) than first timers (27.3%). CONCLUSION: It was evident from this study that repeaters exist among those who seek to be examined for possible contraction of HIV: they are characterized by risk-taking behavior in contracting an HIV infection through sexual contact.

Paraoxonase1 polymorphism Leu-Met55 is associated with cerebral infarction in Japanese population.

BACKGROUND: Paraoxonase1 (PON1) is HDL-associated ester hydrolase which has been shown to prevent LDL and HDL oxidation in vitro. PON1-coding region has two common polymorphisms (M/L55 and A/B192) that influence PON activity. We examined whether these polymorphisms relates with the incidence of cerebral infarction (CI) which is one of the major atherosclerotic disease in Japan. MATERIAL/METHODS: The study population was comprised of 112 unrelated Japanese CI patients and 106 healthy Japanese individuals. The PON1 genotypes were determined by PCR and digestion by specific restriction enzymes. RESULTS: PON1-192 polymorphism revealed no significant difference of genotype and allelic distribution in CI patients and controls. Frequency of L/M alleles in PON1-55 polymorphism (0.88, 0.12, respectively) was different from previously reported frequencies in Caucasians. Comparison of allelic distribution of the PON1-55 polymorphism showed a significant increase of the M allele in CI subjects compared with control subjects. All three subjects with the MM genotype were in the CI group. Of subjects with an AA genotype, the frequencies of the MM and LM genotypes were significantly higher and that of the LL genotype was significantly lower in the CI group compared with the control group. Frequency of the M allele in the CI group was significantly higher in subjects who had the AA genotype. CONCLUSIONS: These findings suggest that the enzyme might be involved in the development of atherosclerosis of cerebral arteries. Moreover, this finding might indicates that the genetic markers in Japanese linked to distinct genetic event from Caucasians.