Sum frequency generation spectroscopic studies on phase transitions of phospholipid monolayers containing poly(ethylene oxide) lipids at the air-water interface.

Vibrational sum frequency generation (SFG) spectroscopy was applied to study the phase transitions of the mixed monolayers of l-alpha-distearoyl phosphatidylethanolamine (DSPE) and DSPE covalently coupled with poly(ethylene oxide) at the amino head group (DSPE-EO(45), DSPE with 45 ethylene oxide monomers) at the air-water interface. The SFG spectra were measured for the mixed monolayers with the mole fractions of DSPE-EO(45) of 0, 1.3, 4.5, 9.0, 12.5, and 16.7% at the surface pressures of 5, 15, and 35 mN/m. The monolayer compression isotherms indicated that the mixed monolayers at 5, 15, are 35 mN/m are mainly in the so-called "pancake", "mushroom", and "brush" states, respectively. The SFG spectra in the OH stretching vibration region give rise to SFG bands near 3200 and 3400 cm(-1). The mean molecular amplitude of the former band due to the OH stretching of the "icelike" water molecules associated mainly with the hydrophilic poly(ethylene oxide) (PEO) chains, exhibits appreciable decrease on compression of the mixed monolayers from 5 to 15 mN/m. The result corroborates the model for the pancake-mushroom transition, which presumes the dissolution of the PEO chains from the air-water interface to the water subphase. Further compression of the mixed monolayers to 35 mN/m causes a slight decrease of the line amplitude, which can be explained by considering a squeezing out of water molecules from the hydrophilic groups of DSPE-EO(45) in the brush state, where the PEO chains strongly interact with each other to form a tight binding state of the hydrophilic groups. The relative intensities of the SFG bands due to the CH3 asymmetric and symmetric vibrations were used to estimate the tilt angles of the terminal methyl group of DSPE, indicating that the angle increases with increasing the mole fraction of DSPE-EO(45). The angles almost saturate at the mole fraction larger than 10%, the saturation angle being nearly 90 degrees at 5 mN/m, ca. 60 degrees at 15 mN/m, and ca. 47 degrees at 35 mN/ m. Then, the introduction of the hydrophilic PEO head group causes a large tilting of the alkyl groups of DEPE in the mixed monolayers.

Chronic Japanese schistosomiasis and hepatocellular carcinoma: ten years of follow-up in Yamanashi Prefecture, Japan.

In a preliminary study carried out in the study area we found that 19.1% (173/907) of patients with chronic liver disease and 51% (35/68) of hepatocellular carcinoma cases were infected with Japanese schistosomiasis. Analysis of data from 571 autopsies revealed a similarly high incidence of schistosomiasis among cases of hepatoma and other liver diseases. A prospective case-control study conducted over 10 years showed that hepatoma developed in 5.4% (26/484) of chronic schistosomiasis cases and in 7.5% (23/307) of patients with chronic liver disease (hepatitis, cirrhosis, etc). The difference was not statistically significant (P = 0.228). A high incidence of hepatitis C virus (HCV) antibody (HCVAb) was found in the schistosomiasis group (36.5%; 95% CI = 44.9-28.1%) and in the chronic liver disease group (56.0%), 39% of whom had chronic hepatitis (P = 0.028). Various factors that might have contributed to the development of hepatoma and schistosomiasis were investigated, but no evidence of a significant correlation between schistosomiasis and hepatoma was found. The high incidence of HCVAb was considered to have been responsible for the development of hepatocellular carcinoma in chronic schistosomiasis patients. The role of HBV infection in the development of hepatoma in schistosomiasis patients was not confirmed after an assay for HCVAb was included in the study.

[Female pseudohermaphroditism].

Patients with female pseudohermaphroditism have female internal genitalia and karyotype (XX) and various degree of external genitalia virilization. External genitalia is musculinized congenitally when female fetus is exposed to excess androgenic environment. Congenital adrenal hyperplasia (CAH), mostly 21-hydroxylase deficiency, is the most common cause. Maternal androgen excess due to maternal ovarian tumor or drug intake also causes female pseudohermaphroditism. Combination of hormonal therapy and surgical correction is required for CAH. When appropriate treatments were given, normal puberty, fertility and child bearing are possible. HLA typing in patient's family is useful for identifying heterozygote and homozygote, because of close linkage of 21-hydroxylase gene and HLA gene. Prenatal diagnosis and genetic diagnosis for female pseudohermaphroditism due to 21-hydroxylase deficiency can be performed, however prenatal treatment is not completely established.

Assessment of human sperm functional changes after in-vitro coincubation with cells retrieved from the human female reproductive tract.

Human spermatozoa must undergo functional changes prior to fertilization; however, the site of this physiological event is still unclear. To evaluate the influence of the female reproductive tract on sperm fertilizing capacity, fertile sperm samples were coincubated with endometrial, oviductal, granulosa and cumulus cells, follicular fluid and maternal serum. Sperm penetration into the zona-free hamster ova and motion parameters were measured daily for 72 h. Compared to control samples, endometrial and oviductal cell cultures did not alter sperm fertilizing capacity or their movement characteristics. Sperm coincubated with follicular fluid, granulosa or cumulus cells exhibited a significantly higher ability to penetrate zona-free hamster ova for up to 48 h. Sperm motility increased at 4 h in the presence of follicular fluid and serum. At 24 h sperm velocity and amplitude of lateral head displacement significantly declined in sperm samples exposed to serum, and velocity also declined in follicular fluid and with coincubation using ovarian follicle cells. Sperm motility and velocity decreased at 48 h in the presence of serum, follicular fluid, cumulus or granulosa cells. Our findings may suggest that specific secretory factors produced in the human pre-ovulatory ovarian follicle enhance human sperm fertilizing capacity.

Sperm motion parameters after suppression of spermatogenesis with a gonadotropin-releasing hormone antagonist plus testosterone supplementation.

OBJECTIVE: To evaluate whether the chronic administration of a GnRH antagonist supplemented with T enanthate affects sperm motion parameters. DESIGN: Prospective study. SETTING: Academic medical research environment. PATIENTS/PARTICIPANTS: Six normospermic men of reproductive age. INTERVENTION: A 20-week treatment included the administration of 10 mg of GnRH antagonist every day and 25 mg of T enanthate once a week. MAIN OUTCOME MEASURE: Computerized sperm motion analysis on each participant every 2 weeks for a period of 11 months. RESULTS: Sperm concentration decreased after 4 weeks of the GnRH antagonist administration, accompanied by a reduction of sperm motility from an initial mean value of 56% to 34% on treatment week 4 and 21% on treatment week 6. In contrast, sperm velocity, linearity, amplitude of the lateral head displacement, and beat cross-frequency values did not significantly change in spite of reduced overall sperm concentration and motility. Azoospermia was reached within 6 to 12 weeks of the GnRH administration, and it was sustained during the treatment period. During recovery of spermatogenesis, sperm movement parameters returned to initial values earlier than sperm concentration and normal morphology. All participants recovered initial semen parameters 20 weeks after the end of treatment. CONCLUSION: The administration of a GnRH antagonist supplemented with T enanthate successfully induced reversible suppression of spermatogenesis. The sperm motion characteristics appeared to be the last parameters to decline and the first to return to initial values after the treatment.

The relationship between trypsin activity in amniotic fluid and premature rupture of membranes.

Trypsin activity and concentration of alpha 1-antitrypsin in amniotic fluid were measured in patients with and without premature rupture of membranes. Trypsin activity in amniotic fluid with premature rupture of membranes (127 +/- 57 U/L) was found to be significantly higher than in cases without premature rupture of membranes (14 +/- 20 U/L) (p less than 0.01). The concentration of alpha 1-antitrypsin in amniotic fluid with premature rupture of membranes (6.8 +/- 5.5 mg/dl) was significantly lower than in cases without premature rupture (25.2 +/- 20.2 mg/dl) (p less than 0.01). Trypsin activity and concentration of alpha 1-antitrypsin in amniotic fluid were not influenced by rupture of membranes and labor. These studies suggest that high trypsin activity and low concentration of alpha 1-antitrypsin in amniotic fluid is one cause of premature rupture of membranes.