The preparation and application of N-terminal 57 amino acid protein of the follicle-stimulating hormone receptor as a candidate male contraceptive vaccine.

Follicle-stimulating hormone receptor (FSHR), which is expressed only on Sertoli cells and plays a key role in spermatogenesis, has been paid attention for its potential in male contraception vaccine research and development. This study introduces a method for the preparation and purification of human FSHR 57-amino acid protein (FSHR-57aa) as well as determination of its immunogenicity and antifertility effect. A recombinant pET-28a(+)-FSHR-57aa plasmid was constructed and expressed in Escherichia coli strain BL21 Star TM (DE3) and the FSHR-57aa protein was separated and collected by cutting the gel and recovering activity by efficient refolding dialysis. The protein was identified by Western blot and high-performance liquid chromatography analysis with a band of nearly 7 kDa and a purity of 97.4%. Male monkeys were immunized with rhFSHR-57aa protein and a gradual rising of specific serum IgG antibody was found which reached a plateau on day 112 (16 weeks) after the first immunization. After mating of one male with three female monkeys, the pregnancy rate of those mated with males immunized against FSHR-57aa was significantly decreased while the serum hormone levels of testosterone and estradiol were not disturbed in the control or the FSHR-57aa groups. By evaluating pathological changes in testicular histology, we found that the blood-testis barrier remained intact, in spite of some small damage to Sertoli cells. In conclusion, our study demonstrates that the rhFSHR-57aa protein might be a feasible male contraceptive which could affect sperm production without disturbing hormone levels.

[Photoinduced electron transfer between [Ru(bpy)3]2+ and copper(II) ion in composite films mediated by DNA].

An orange-red [Ru(bpy)3]2+ -DNA-CU2 composite film (bpy = 2,2'-bipyridine) was fabricated on an indium-tin (ITO) surface based on electrostatic interactions among [Ru(bpy)3]2+, DNA and Cu2+ by using self-standing cast methods. The photoinduced electron transfer (PET) properties of the resultant composite film mediated by DNA were studied by means of steady-state and time-resolved fluorescence spectroscopy, UV-visible absorption spectroscopy, fluorescence microscopic imaging and scan electron microscopy. The [Ru(bpy)3]2+ -DNA-Cu2+ composite film with molar ratio of 10:20:1 shows an obvious absorption band (450 nm) and an intense emission peak (lamda(em) = 595 nm), whose emission exhibits a single-exponential decay with tau = 188.6 ns and is quenched by Cu2+ via DNA-mediated PET mechanism, indicating that the quenching constant is 6.94 x 10(3) L x mol(-1) and quenching rate constant is 3.80 x 10(10) L x mol(-1) x s(-1). The increasing molar ratio of Cu2+ in composite films (10-fold) leads to an 11 nm blue-shift of the emission peak, which is dramatically weakened by Cu2+ via a static quenching mechanism. In addition, compared with the emission quenching of DNA-[Ru(bpy)2 (tatp)]2+ (tatp = 1, 4, 8, 9-tetra-aza-triphenylene) tuned by Cu2+, which is present either in solutions or in composite films, Cu2+ only quenches the emission of [Ru(bpy)3]2+ bound to DNA via an electrostatic interaction mode in composite films.

Associations of prenatal exposure to phenols with birth outcomes.

Many phenols are known to mimic or antagonize hormonal activities and may adversely affect fetal growth. A study of 567 pregnant women was conducted to investigate the relationship between prenatal phenol exposure and birth outcomes, including birth weight, length, and gestational age. We measured the concentrations of bisphenol A, benzophenone-3, 4-n-octylphenol and 4-n-nonylphenol in maternal urine and examine their association with birth outcomes. Categories of urinary benzophenone-3 concentration were associated with decreased gestational age in all infants (p for trend = 0.03). Between middle and low exposure groups, we also found bisphenol A was negatively associated with gestational duration (ßadjusted = -0.48 week; 95% confidence interval: -0.91, -0.05). After stratification by gender, we found the consistent results in infant boys with those in all infants, but we did not observe significant association for girls. In conclusion, we found prenatal phenol exposure was sex-specifically related to birth outcomes.

[Effects of di-butyl phthalate on the reproductive system of adolescent male rats].

OBJECTIVE: To explore the effects of di-butyl phthalate (DBP) on the reproductive system of adolescent male rats. METHODS: Sprague-Dawley (SD) rats aged 5 weeks were assigned to receive corn oil (vehicle control) or DBP orally at 10, 100 and 500 mg/(kg x d) for 30 days. After the exposure, the testis, epididymis, liver and pituitary of the rats were weighted and their ratios to the body weight obtained. Histopathological changes of the testis and epididymis were examined by Hematoxylin-eosin staining, the levels of testosterone (T), luteinizing hormone (LH) and follicle stimulating hormone (FSH) in the serum were measured by radioimmunoassay, and the relative mRNA expressions of the steroidogenesis acute regulatory protein (StAR), proliferating cell nuclear antigen (PCNA), cytochrome P450 cholesterol side chain cleavage enzyme (P450scc) and scavenger receptor (SR) were detected by real-time quantitative RT-PCR. RESULTS: DBP induced significant histopathological changes in the testicular tissue at 100 and 500 mg/(kg x d), and decreased the testicular and epididymal weights, inhibited the mRNA expressions of StAR and PCNA, reduced the levels of T and LH, and elevated the level of FSH at 500 mg/(kg x d). At the dose of 10 mg/(kg x d), DBP increased serum LH and FSH and the mRNA expression of P450scc. While the SR mRNA expression showed no significant changes in all the groups. CONCLUSION: High level of DBP has apparent toxic effect on reproductive system of male rats. Low - dose DBP can increase the level of serum gonadotropin LH and affect the mRNA expression of P450scc in the testis.

[Experimental study of repairing skull defect with autogenous cranial bone dust].

OBJECTIVE: To build animal model of skull defect for the basic research of skull defects reconstruction with autogenous cranial bone dust and its relevance to the clinical application. METHODS: Three full-thickness parietal skull defects (A, B and C) were created in 30 New Zealand white rabbits. The size of all the defects was 1 cm in diameter. The defect A was left untreated as control. Defects B and C were reconstructed with autogenous cranial bone dust. Two pieces of pyroxylin membrane were placed on the top and bottom of the defect B. every 10 rabbits were killed for analysis at 4, 8, 12 weeks after operation. RESULTS: Defect A was largely repaired with connective tissue. Defect B was repaired rapidly with newly formed cancellous bone in the early period, but the following process of the growth, remodeling and maturing of the newly-formed cancellous bone was slowly. The bone ingrowth in defect C was more mature, but could not repair the defect completely, especially in the central zone. The grafted bone dust was absorbed gradually. Active angiogenesis could be observed in the newly formed bone. For the same defect, new bone had a greater amount of calcium at 12 weeks than at 4 and 8 weeks after operation (P < 0.05). And the calcium content of new bone was higher in defect C than in defect B at 8, 12 weeks after operation (P < 0.05). CONCLUSIONS: The osteogenesis and angiogenesis are closely related to the time and location. The pyroxylin membrane can significantly promote the formation of cancellous bone in defect with autogenous bone dust graft during the early period.

[The reconstruction of funnel chest deformity with the reversed transplantation of sternum-costicartilage flap carried by the abdominal rectus pedicle].

OBJECTIVE: To investigate the reconstructive operative procedures of funnel chest with "sternum-costicartilage" flap carried by the abdominal rectus pedicle. METHODS: (1) In accordance with the lesioned area of funnel-like depressed deformity of anterior thoracic wall, a perpendicular median incision was designed and made; (2) The "sternum-costicartilage" flap carrying the abdominal rectus pedicle was used and reversed and transplanted to reconstruct severe funnel chest deformity. RESULTS: The procedure was used in 7 cases from 1999 to 2005. The results of surgery were satisfactory. There were no recurrence after operation. CONCLUSIONS: The procedure reported here is rather safe, solid and sound with good therapeutic results, and is of great value in clinical practice.