Promotive effects of a silk film on epidermal recovery from full-thickness skin wounds.

We examined the effects of the transparent fibroin film (silk film) on full-thickness skin wounds. Full-thickness dermatotomies (15 mm x 9 mm) were prepared on the dorsal wall of CRJ:CD-1 nu/nu (ICR nu/nu) mice. The area of the wounds dressed with silk film was reduced to 10% of that made by the dermatotomy 14 days after the dermatotomy and were covered with regenerated epidermis 21 days after the dermatotomy. In contrast, less recovery and epidermal regeneration were found 14 days after dermatotomy in the wounds dressed with a conventional hydrocolloid dressing (Duro Active). Furthermore, only partial incomplete epidemal growth was obtained 21 days after dermatotomy. Most importantly, the healing time of wounds dressed with silk film was 7 days shorter than those dressed with DuoActive dressing. The silk film showed an almost similar or slightly better promotive effect as the lyophilized porcine dermis (Alloask D), which is used as a dressing for burns, ulcers, and decubitis. Histologic findings revealed that there was greater collagen regeneration and less inflammation and neutrophil-lymphocyte infiltration of the wounds dressed with silk film than with DuoActive dressing. It is clear that regeneration of the epidermis and dermis of the wound beds covered with silk film was faster than with DuoActive dressing. Finally, silk film is easily obtainable, sterilizable, and transparent, and it allows easy observation of tissue recovery. Therefore, silk film offers advantages over other dressings and may be clinically useful for wound treatment.

Sn-1,2-diacylglycerols and phorbol ester stimulate the production of progesterone from the human placenta.

Human term placental explants were used to investigate the possible role of phospholipid-sensitive and Ca2+ dependent protein kinase in the regulation of human placental progesterone production. Placental tissue was incubated with low density lipoprotein as a precursor of progesterone in the presence or the absence of phorbol 12-myristate-13-acetate, 1-oleoyl-2-acetyl-glycerol, and the calcium ionophore A23187. The rate of progesterone production by placental tissue was 21.7 +/- 4.6 ng. (mg wet wt)-1.(2 h)-1 (mean +/- SEM) with 500 mg low density lipoprotein/l (control). The rate of progesterone production was accelerated 2-fold by 1 nmol/l phorbol 12-myristate-13-acetate, 1.6-fold by 250 mumol/l 1-oleoyl-2-acetyl-glycerol and this increase was dose-related (25-250 mumol/l 1-oleoyl-2-acetyl-glycerol). A nonpromoting derivative, 4 alpha-phorbol-12,13-didecanoate had no effect. The phorbol 12-myristate-13-acetate or 1-oleoyl-2-acetyl-glycerol induced stimulation of progesterone production was not associated with a change in the intracellular cAMP level. Addition of 10 mumol/l A23187 further increased progesterone production with 125 mumol/l 1-oleoyl-2-acetyl-glycerol. The rate of progesterone production was accelerated 1.6-fold by 125 mumol/l 1-oleoyl-2-acetyl-glycerol and 10 mumol/l A23187 as compared with control. The effects of the phorbol ester and the diacyl glycerol were completely blocked by the addition of the protein synthesis inhibitor cycloheximide. We conclude that these phorbol regents are able to stimulate human placental progesterone production. The possible roles of intracellular Ca2+ and protein kinase C in placental steroidogenesis are discussed.

The roles of Ca2+ and adenosine 3',5'-monophosphate in the regulation of progesterone production by human placental tissue.

The effects of Ca2+ and cAMP on progesterone production by placental tissue were studied. Term placentas obtained from normal pregnant women were perfused with sterile saline to remove blood, and the minced trophoblastic tissue was incubated in vitro. The rate of progesterone secretion by the trophoblastic tissue was 47.5 +/- 5.0 (+/- SE) ng/mg cell protein X h (control) at 450 micrograms low density lipoprotein/mL. The rates of progesterone production and cAMP accumulation were accelerated 3.0- and 1.7-fold, respectively, by 10(-5) M terbutaline, and the terbutaline effect was blocked by the addition of 50 microM N-(6-aminohexyl)5-chloro-1-naphthalenesulfonamide (W-7) or 50 microM trifluoperazine. Whereas progesterone secretion by placental explants cultured in medium containing low density lipoprotein with 1 microM A23187 (calcium ionophore) reached a rate of 128.5 +/- 8.5 ng/mg cell protein X h, incubation of placental explants with A23187 caused a highly significant, dose-related decrease in terbutaline-stimulated cAMP accumulation in the presence of 3-isobutyl-1-methylxanthine, a phosphodiesterase inhibitor. Inhibition by A23187 was Ca2+ dependent, since incubation in a Ca2+-free medium with EGTA blocked its effect. Intracellular Ca2+ is apparently necessary for placental progesterone production; enhancement of progesterone production by beta2-stimulation is mediated by intracellular Ca2+ and cAMP.

[Synthesis and metabolism of estriol conjugates].

As an indicator of fetal well being, the urinary estriol value is widely utilized. But the discrepancy between the results of NST and urinary estriol value has recently been pointed out. The estimation of plasma estriol is also recommended as a more reliable means of fetal assessment than that of urinary estriol. The purpose of the study is to clarify the patterns of estriol conjugates in maternal blood, retroplacental blood and cord blood, and further to elucidate the metabolism and secretion of each conjugate in organs and to determine the most useful conjugate as a source of fetal information. In normal pregnancy urine, estriol glucosiduronate is the dominant component of urinary estriol. In preeclampsia, the percentage of G decreased and that of G-S increased. In retroplacental blood, G-S is the main conjugate. On the other hand in cord blood, S is the dominant conjugate. The placental perfusion experiment revealed that the placenta hydrolyzed each conjugate to a free form and did not convert one conjugate to another. Periodical determination of plasma estriol conjugates in pregnant women revealed that the G-S fraction fluctuated most during parturition. The importance of liver as a possible site for estriol conjugation and the role of kidney in selective clearance of estriol conjugates are discussed.

[The development of enzyme immunoassay for prostaglandin F2 alpha].

It has recently been demonstrated that prostaglandins (PGs) play an important role in the ovulation, the onset of menstruation and labor pain and other reproductive phenomena. The purpose of this study is to develop the enzyme immunoassay (EIA) for PGF2 alpha to estimate the PGF2 alpha level in body fluids. beta-Galactosidase-PGF2 alpha conjugate and bovine serum albumin-PGF2 alpha conjugate were prepared by a mixed anhydride method. PGF2 alpha was extracted with ethylacetate from an acidified sample. EIA was carried out using a double antibody method. As for the conjugation ratio of PGF2 alpha and beta-Galactosidase, 5, 10, 20, 40 and 80 were examined. Recovered enzyme activity and sensitivity of the method were better in the enzyme of conjugation ratio 10 than in the other conjugation ratios, 5, 20, 40, 80. Values measured by RIA and EIA were well correlated. The correlation rate was 0.84. The recovery rate was 102.3%. The sensitivity of the standard curve was 5-100 pg/tube. PGF2 alpha in the menstrual blood of the 18 women was determined with the EIA method. The mean value for PGF2 alpha in menstrual blood is 20.9 ng/ml (S.D. = 11.4).

Abortifacient effect and uterine cervix-dilating action of 16, 16-dimethyl trans delta 2 PGE1 methyl ester (ONO 802) in the form of a vaginal suppository (a randomized, double-blind, controlled study in the second trimester of pregnancy).

A newly synthesized 16, 16-dimethyl trans delta 2 PGE1 methyl ester (ONO 802) was clinically applied in the form of a vaginal suppository for therapeutic abortion of second trimester pregnancies. Its effects were studied in a double-blind test comparing it with an inactive placebo suppository. The study was conducted at 12 Japanese university hospitals. The number of patients was 125 in total, i.e. 63 receiving ONO 802 vaginal suppository (containing 1.0 mg ONO 802) and 62 receiving inactive placebo suppository. ONO 802 was more effective than placebo with a success rate of 87% (complete (71%) and incomplete (16%) abortions). The onset of uterine contractions was observed in 154.3+/-18.1 min. and the onset of uterine bleeding in 323.6+/-41.0 min. The expulsion of the fetus and placenta was observed in 955.4+/-97.0 and 961.6+/-97.0 min., respectively. The cervix dilating effect of ONO 802 was observed in 63.5% of the patients at 3 hours after the start of administration. Nausea, vomiting, abdominal cramps, diarrhea and pyrexia were noticed. However, all these side effects were transient and mild, requiring no treatment. No abnormality was observed in the puerperal course, duration of uterine bleeding or onset of subsequent menstruation following the therapeutic abortion. Therefore, the present study demonstrated that ONO 802 vaginal suppository was an effective and valuable drug for therapeutic abortion of second trimester pregnancies.

[Prostaglandins and dysmenorrhea effect of naproxen on prostaglandin concentrations in menstrual blood (author's transl)].

It has recently been demonstrated that prostaglandins play an important role in human reproductive system. The purpose of this study is to demonstrate the involvement of PGs in the onset of menstruation and in the cause of dysmenorrhea. In human endometrium PGF2 alpha were found in large amount in late luteal phase and especially in premenstrual period. PGE1 and PGF2 alpha concentrations in menstrual bloods were 3 to 4 times higher in dysmenorrheic subjects as compared to normal women. The high PGE1 and PGF2 alpha concentration of patients decreased to normal level in naproxen treated cycle. And the intensity of abdominal pain and lumbago decreased simultaneously. On the other hand, in normal woman, naproxen gave little effect on PGs concentration of menstrual fluids. High levels of PGs in dysmenorrheic subjects, decrease of PGs concentration by naproxen treatment and simultaneous alleviation of pain suggest the involvement of PGs in the cause of dysmenorrhea.

[Changes of prostaglandin receptors in myometrium--interaction between steroids and prostaglandins--(author's transl)].

One of the most important actions of prostaglandins (PGs) is contraction of myometrium. On the other hand, the inhibitory action of progesterone(P) on myometrial contraction is well known. The purpose of this study is to elucidate the mechanism of uterine contraction, analyzing the interaction between PGs and steroids on the receptor level. 1) PG receptor in myometrium was increased after the administration of estradiol (E) into castrated rabbits and addition of P and E enhanced the increases of PG receptor. On the contrary, PGF2 alpha in myometrium was decreased by E, but addition of P and E recovered the decrease. 2) P receptor was increased after the injection of PG in the castrated rabbits, but E receptor showed no significant changes in its level. These results suggest that PG acts on myometrium partly through the changes of steroid hormone receptor and vice versa. 3) PGE1 and PGF2 alpha receptor in pregnant rabbits were increased 4 hours after castration. From these results, it becomes clear that the increase of PG receptor and PG synthesis play an important role in the onset of uterine contraction.

[Studies on the mechanism of the onset of menstruation (author's transl)].

It has recently been demonstrated that prostaglandins (PGs) play roles in human reproduction, especially in ovulation and menstruation. The purpose of this study is to elucidate the mechanism of the action of PGs upon the onset of menstruation. By measuring the concentration of PGs in human endometrium from the women with normal menstrual cycles, PGF2 alpha was present in large amounts in late luteal phase. The activity of PG-synthetase and phospholipase A, which are key enzymes of PG-biosynthesis, also increased in late luteal phase. PG-receptor which is thought to be important to biological action of PGs showed no remarkable change throughout human menstrual cycle. These studies clarify the possibility that there is apparent correlation between the onset of menstruation and PGs.

Termination of early pregnancy by ONO-802 (16,16-dimethyl-trans-delta2-PGE1 methyl ester).

ONO-802 was infused into the uterine cavity for the termination of early pregnancy in 45 healthy volunteers. Forty two (93%) of the 45 cases had complete abortions and two had incomplete abortions. Nine (20%) of the 45 volunteers complained of nausea, 7 (16%) vomited and 5 (11%) complained of abdominal pain. Neither diarrhea nor weakness was observed. These results suggest that ONO-802 is more acceptable for the termination of early pregnancy than is PGF2alpha.