The purpose of this study is to inquire histologically when red muscle fibers and white muscle fibers are differenciated and how they develope, considering from sex difference.
Wistar-strain rats of the same venter were used in this experiment. The animals of both sexes were killed at the interval of five days, from birth to 25 days. Two groups of male and female rats of 70 days old after birth were used as control groups.
M. tibialis ant. was removed and then fixed in 10% formalin for approximately two weeks. As staining, alchohol solution of Sudan black B was used.
The results are as follows :
1) Sex difference in rats' body weight was started to appear about 15 days after birth.
2) Differentiation of red muscle fibers and white muscle fibers in M. tibialis ant. was recognized about 15 days after birth in male and female rats.
3) The entire area of cross section of M. tibialis ant. is increasing during the development of rats' body as a whole. No apparent tendency on sex difference was found till 25 days after birth. On 70 days after birth the entire area of cross section in male has about 1.5 times the size of female.
4) No increase of number in M. tibialis ant. was recognized during the development of rats' body as a whole and no sex difference in number of muscle fibers.
5) The area of cross section per fiber and the average diameter of fibers are increasing during the growth of rats' body. No sex difference of those in red and white muscle fibers was found till 25 days after birth but, on 70 days after birth, it became clear. The rate of hypertrophy of white muscle fibers is greater than that of red muscle fibers.
6) Ratio of the entire area of muscle fibers to the intercelluler space in M. tibi-alis ant. is increasing during the development of rats' body.
7) No difference of area of cross section per fiber in peripheral and innermost regions was found till about 15 days after birth. On 70 days after birth the red muscle fibers in peripheral have 1.4 times the size of those in innermost, and the white muscle fibers 1.3 times.

In 2000, an equine Yamakagashi (Rhabdophis tigrinus) antivenom (Lot 0001) was testmanufactured as an unapproved drug for treatment of Yamakagashi bites. It was stocked on the premise of super-legal use from the viewpoint of emergency health crisis management. The antivenom showed a strong neutralizing ability against the hemorrhagic and coagulation activity of the Yamakagashi venom in its potency test. One vial of the antivenom can effectively neutralize at least about 4 mg of Yamakagashi venom. Its efficacy has also been confirmed in patients with severe cases of R. tigrinus bite that has been used in emergency. In 2020, this antivenom (Lot 0001) has reached 20 years after its production. To evaluate the integrity and potency of the antivenom, quality control, safety and potency tests had been conducted almost every year since 2012. Physical and chemical tests (property test, moisture content test, insoluble foreign matter test, osmotic pressure ratio test, pH test, protein content test, endotoxin test, sterility test) of the antivenom, showed no significant changes throughout the years, when compared to the results immediately after its production in 2000. All the parameters measured were also within the standard values. In animal safety tests (test for absence of toxicity and pyrogen), there was no change in the test results during the storage period and no abnormalities were observed. The potency test (anti-coagulant activity) after 20 years of the product, showed the same potency as those recorded immediately after production. Therefore, in all of the stability monitoring tests conducted so far, the product did not show any significant change compared to the results immediately after production. This confirms the stability of the product during the stockpiling period to the present, that is, 20 years after production.

Schistosomiasis japonica is one of seven NTDs endemic in the Philippines that continues to threaten public health in the country. The causative agent, the blood fluke Schistosoma japonicum, uses an amphibious snail Oncomelania hupensis quadrasi which can harbor larval stages that multiply asexually, eventually producing the infective cercariae which are shed into the water. Contamination of freshwater bodies inhabited by the snail intermediate host occurs through release of human and animal feces containing S. japonicum eggs. Miracidia hatching from these eggs subsequently infect the snails that inhabit these water bodies. The degree of fecal contamination can vary across snail sites and influences snail infection rates in these sites. In this study, conventional malacological surveys using intensive manual search for snails were conducted from 2015 to 2016 in seven selected endemic provinces, namely Leyte and Bohol in the Visayas and Surigao del Norte, Agusan del Sur, Bukidnon, Lanao del Norte and Compostela Valley in Mindanao. A total of 6,279 O. hupensis quadrasi snails were collected from 38 snail sites. The municipality of Trento in Agusan del Sur recorded the highest number of snail sites (7) that yielded O. hupensis quadrasi snails while only one snail site was found positive for O. hupensis quadrasi snails in Kapatagan in Lanao del Norte and Talibon in Bohol. Alegria in Surigao del Norte yielded the highest number of snail sites (5) that were found to harbor snails positive for S. japonicum infection. The snail infection rates in this municipality ranged from 0.43% to 14.71%. None of the snails collected from Talibon in Bohol was infected. Bohol is the only province among the 28 schistosomiasis-endemic provinces which has reached near elimination status. Snail infection rates were found to vary considerably across snail sites, which could be due to the degree of fecal contamination of the snail sites and their connectivity to water that can serve as contamination source.