P–146 Differential impact of three embryo culture media for IVF on in vitro development and perinatal outcome: a single-center RCT

Study question

This report provides updated data from an RCT determining which embryo culture medium yields optimal IVF outcomes.

Summary answer

Embryo culture systems used for IVF differentially affected preimplantation development and resultant obstetric and perinatal outcomes, including birthweights of live-born singletons.

What is known already

Currently, multiple embryo culture medium systems are in use for IVF, raising questions regarding which is optimal. However, the ability of a medium to yield preimplantation embryos is not necessarily indicative of embryo viability. For example, supplementation of medium with serum was commonly used to increase animal blastocyst yields, but this impaired embryonic, fetal, and offspring health. In humans, medium composition and culture duration can influence IVF efficacy and offspring phenotype. Given the importance of culture systems in determining clinical outcomes, existing data regarding differential culture system impacts are insufficient and additional well-designed studies are required.

Study design, size, duration

Between February 2016 and August 2017, 795 couples undergoing their first autologous clinical IVF cycle and freeze-all strategy were recruited. Participants were randomized via computer-generated tables into three groups. Following standard oocyte retrieval and IVF/ICSI procedures, embryos were cultured using three different culture media, G1 Plus/G2 Plus (G1/G2; Vitrolife), Global Total (GT; LifeGlobal), or Sequential Cleav/Sequential Blast (SC/SB; Origio). Thirty-eight patients exhibiting no 2PN oocytes following insemination or those undergoing fresh embryo transfers were excluded.

Participants/materials, setting, methods

For patients yielding a single good-quality cleavage-stage (day–2 or day–3) embryo, that cleavage-stage embryo was vitrified. For patients yielding two or more good-quality cleavage-stage embryos, two or less good-quality cleavage-stage embryos were vitrified. The culture period of the remaining embryos was extended, and all good-quality blastocyst-stage (day–5 or day–6) embryos were vitrified. This report presents data for vitrified embryo transfer performed until the end of December 2020.

Main results and the role of chance

The mean per-cycle vitrified embryo yield (± SD) was comparable between groups for cleavage-stage embryos, but significantly different for blastocyst-stage embryos (G1/G2: 1.69 ± 2.2, GT: 2.53 ± 3.01, SC/SB: 2.04 ± 2.42; P = 0.001). Following vitrified cleavage- or blastocyst-stage embryo transfers, biochemical pregnancy rates were significantly different between groups (G1/G2: 55.6%, GT: 59.1%, SC/SB: 46.2%; P = 0.011). Furthermore, a between-group trend towards different live birth rates was observed (G1/G2: 41.7%, GT: 42.1%, SC/SB: 33.1%; P = 0.063). Of 382 live births, data for first-borns (n = 323; 295 singletons and 14 twin-pairs) are reported here. Perinatal data did not differ significantly between groups for both cleavage- and blastocyst-stage embryo transfers, including gestational age- and gender-adjusted singleton birthweight (z-score). Following multiple linear regression (including selected covariates), adjusted mean singleton birthweights were significantly lower in the G1/G2 and GT groups than in the SC/SB group (by 131 g; P = 0.011 and 110 g; P = 0.032, respectively) and tended to be lower for cleavage-stage embryo transfers than for blastocyst-stage embryo transfers (by 102 g; P = 0.053).

Limitations, reasons for caution

A larger cohort size and longer-term follow-up are required to verify and further elucidate the impact of embryo culture methods on child health. Such studies will raise awareness regarding the sensitivity of in vitro-cultured human embryos to their environment, ultimately resulting in practices that decrease IVF risks to offspring.

Wider implications of the findings: Pregnancy outcome of the medium yielding fewer blastocysts was comparable or superior to that of other media, highlighting the importance of differentiating between the ability to support preimplantation development versus the ability to yield viable embryos. Embryo culture medium had a greater impact than embryo transfer stage on live birthweight.

Trial registration number

UMIN000020910

P–221 Prospective randomized sibling study on gamete preparation, insemination and subsequent culture of human oocytes in a time-lapse system using media systems with and without antioxidants

Study question

Does the addition of antioxidants for gamete preparation, insemination and embryo culture lead to differences in embryo development and clinical outcome

Summary answer

Using an antioxidant-containing media system for sperm preparation, insemination and embryo culture imparts significantly higher good-quality blastocyst rates and improved clinical outcome in elderly patients.

What is known already

A previous study showed that adding combined antioxidants for sequential embryo culture in conventional incubators (interrupted culture) improves embryo viability and clinical outcome, especially for elderly patients. Here we investigated the combined effect of three antioxidants Acetyl-L-Carnitine (10 µM), N-Acetyl-L-Cysteine (10 µM), and α-Lipoic Acid (5 µM) during sperm preparation, insemination, and time-lapse culture in a single step medium on human embryo development and clinical outcome.

Study design, size, duration

Prospective randomized single center study including 143 couples for IVF/ICSI between August 2018 and December 2019. Inclusion required at least eight cumulus-oocyte-complexes (COCs) after retrieval. Cycles involving PGT, split IVF/ICSI, and surgically retrieved sperm were excluded. Immediately after retrieval oocytes were randomly distributed to a study or control media system with or without antioxidants (Vitrolife). Similarly, ejaculates were split and prepared with and without antioxidants.

Participants/materials, setting, methods

Sibling oocytes were inseminated in the respective group with accordingly prepared sperm. Single step embryo culture was conducted in medium with (Gx-TL) and without (G-TL) antioxidants in the EmbryoScope+. Embryo quality and clinical outcome were assessed in relation to maternal age (<35/>35 years). Good-quality embryos on day 3 were defined as 8- to 10-cells with even cells and low fragmentation; good-quality blastocysts as > 3BB. Clinical outcome was assessed after single vitrified blastocyst transfer (SVBT).

Main results and the role of chance

From 143 participants (female age, 34.7±3.2 years), a total of 2424 COCs were collected; 1180 COCs/916 metaphase-II (MII) oocytes were allocated to Gx-TL media and 1244 COCs/981 MII oocytes to G-TL media. Age-related analysis in Gx-TL compared with G-TL in relation to allocated MII oocytes revealed a trend for higher fertilization rates in Gx-TL for both age groups (<35: 72.1% vs. 66.9%; >35: 70.7% vs. 64.9%, P < 0.1). Good-quality day 3 embryo development/MII oocytes was higher, albeit not significant, in the elderly patients in Gx-TL (<35: 35.9% vs. 34.4%; >35: 31.1% vs. 27.9%). Overall day 5/6 blastocyst rate was similar for both media (<35: 48.2% vs. 49.9%; >35: 42.3% vs. 39.5%). Day 5/6 GQB rate was comparable for younger patients (<35: 23.8% for Gx-TL vs. 26.0% for G-TL) but significantly higher in Gx-TL in elderly patients (>35: 20.7% vs. 14.4%; P < 0.05). A total of 200 SVBT were performed; 99 in the Gx-TL- and 101 in the G-TL-arm. We noted almost similar implantation and ongoing pregnancy rates between Gx-TL vs G-TL in the younger (<35) age group (50.0% vs. 55.4%; 50.0% vs. 55.6%) but higher albeit not significant rates for Gx-TL in older (>35) patients (44.1% vs. 33.3%; 44.1% vs. 33.3%).

Limitations, reasons for caution

In almost 95% of the cycles, oocytes were inseminated by ICSI; thus results may not equally apply for cycles with IVF. The use of a closed time-lapse system may have prevented from some environmental oxidative stress. Therefore results may come out different with a similar study using standard incubation.

Wider implications of the findings: Supplementation of antioxidants to media for gamete isolation and preparation, as well as subsequent single step time-lapse culture may improve GQE/B rates and clinical outcomes in certain age groups, plausibly through the reduction of oxidative stress. Further studies in selected sub-groups (severe OAT syndrome / testicular cases) may be indicated.

Trial registration number

UMIN000034482

Alteration in faecal bile acids, gut microbial composition and diversity after laparoscopic sleeve gastrectomy

Background

Laparoscopic sleeve gastrectomy (LSG) is a well established treatment for severe obesity and type 2 diabetes. Although the gut microbiota is linked to the efficacy of LSG, the underlying mechanisms remain elusive. The effect of LSG for morbid obesity on the gut microbiota and bile acids was assessed here.

Methods

Severely obese subjects who were candidates for LSG were included and followed until 6 months after surgery. The composition and abundance of the microbiota and bile acids in faeces were assessed by 16S ribosomal RNA sequencing, quantitative PCR and liquid chromatography–mass spectrometry.

Results

In total, 28 patients with a mean(s.d.) BMI of 44·2(6·6) kg/m2 were enrolled. These patients had achieved excess weight loss of 53·2(19·0) per cent and showed improvement in metabolic diseases by 6 months after LSG, accompanied by an alteration in the faecal microbial community. The increase in α-diversity and abundance of specific taxa, such as Rikenellaceae and Christensenellaceae, was strongly associated with reduced faecal bile acid levels. These changes had a significant positive association with excess weight loss and metabolic alterations. However, the total number of faecal bacteria was lower in patients before (mean(s.d.) 10·26(0·36) log10 cells per g faeces) and after (10·39(0·29) log10 cells per g faeces) operation than in healthy subjects (10·83(0·27) log10 cells per g faeces).

Conclusion

LSG is associated with a reduction in faecal bile acids and greater abundance of specific bacterial taxa and α-diversity that may contribute to the metabolic changes.

Abstract P4-11-02: Subjective and objective assessment of efficacy of frozen gloves and socks to prevent nab-paclitaxel-induced peripheral neuropathy in patients with breast cancer

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a frequent side-effect of taxanes which play a central role in the treatment of breast cancer. CIPN can negatively influence long-term quality of life, warranting the development of effective prevention strategies. This study investigates the efficacy of frozen gloves and socks (FGS) in reducing the incidence and severity of nab-paclitaxel-induced peripheral neuropathy. Endpoints were evaluated using both clinician and patient reports.

Methods: This is a multicenter phase II single arm trial study of the effects of FGS for advanced or metastatic breast cancer patients receiving nab-paclitaxel (260 mg/m2) every 3 weeks. Patients wore FGS on their diseased side hand and foot for 60 min during infusion. The other side acted as the untreated control. CIPN was assessed using Patient Neurotoxicity Questionnaire (PNQ), PRO-CTCAE and CTCAE at baseline and every cycle of nab-paclitaxel. The primary endpoint was the incidence of CIPN assessed by PNQ (grade C or higher) after receipt of up to 4 cycles of nab-paclitaxel.

Results: Between September 2012 and January 2015, 50 patients from 16 sites were enrolled in this study. Of 50 patients, 27 (54%) received at least 4 cycles of nab-paclitaxel. There was a trend for the incidence of CIPN assessed by PNQ and PRO-CTCAE to be lower in the intervention side than in the control side, although this difference was not statistically significant. The incidence of CIPN assessed by CTCAE was significantly lower in the treated hand (Table).

Conclusions: Among breast cancer patients who received nab-paclitaxel, FGS produced favorable effects as detected by reduced clinician-reported CTCAE grades for CIPN, although the study did not detect differences in self-reported symptoms of CIPN using PRO-CTCAE or PNQ. Clinical trial information: UMIN000007907.

Difference according to the evaluation method of CIPN   Hands (%)  Feet (%)   InterventionControlp*InterventionControlp*Patient-Reporting CIPNPNQ (grade C or higher)12190.3416160.63Patient-Reporting CIPNPRO-CTCAE       Severity ≥ Moderate13180.0815160.56 Interference ≥ Somewhat7100.328100.32Clinician-Grading CIPNCTCAE (≥ Grade II)15190.0314131.0

*McNemar's test

Citation Format: Yamashita T, Hattori M, Nakada T, Hayashi T, Kamei K, Tatsuya T, Nagao Y, Mase T, Wada M, Mizuno T, Shimozuma K, Iwata H, Yamaguchi T. Subjective and objective assessment of efficacy of frozen gloves and socks to prevent nab-paclitaxel-induced peripheral neuropathy in patients with breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-11-02.

Factors predicting early postpartum glucose intolerance in Japanese women with gestational diabetes mellitus: decision-curve analysis

AIMS

To identify factors predicting early postpartum glucose intolerance in Japanese women with gestational diabetes mellitus, using decision-curve analysis.

METHODS

A retrospective cohort study was performed. The participants were 123 Japanese women with gestational diabetes who underwent 75-g oral glucose tolerance tests at 8-12 weeks after delivery. They were divided into a glucose intolerance and a normal glucose tolerance group based on postpartum oral glucose tolerance test results. Analysis of the pregnancy oral glucose tolerance test results showed predictive factors for postpartum glucose intolerance. We also evaluated the clinical usefulness of the prediction model based on decision-curve analysis.

RESULTS

Of 123 women, 78 (63.4%) had normoglycaemia and 45 (36.6%) had glucose intolerance. Multivariable logistic regression analysis showed insulinogenic index/fasting immunoreactive insulin and summation of glucose levels, assessed during pregnancy oral glucose tolerance tests (total glucose), to be independent risk factors for postpartum glucose intolerance. Evaluating the regression models, the best discrimination (area under the curve 0.725) was obtained using the basic model (i.e. age, family history of diabetes, BMI ≥25 kg/m² and use of insulin during pregnancy) plus insulinogenic index/fasting immunoreactive insulin <1.1. Decision-curve analysis showed that combining insulinogenic index/fasting immunoreactive insulin <1.1 with basic clinical information resulted in superior net benefits for prediction of postpartum glucose intolerance.

CONCLUSIONS

Insulinogenic index/fasting immunoreactive insulin calculated using oral glucose tolerance test results during pregnancy is potentially useful for predicting early postpartum glucose intolerance in Japanese women with gestational diabetes.

334 FACTORS AFFECTING HEMATOPOIETIC ENGRAFTMENT OF MONKEY EMBRYONIC STEM CELLS IN SHEEP FETUSES

Previously, we generated monkey/sheep haematopoietic chimeras by in utero transplantation (IUT) of monkey embryonic stem (ES); however, the factors that control how the ES cells successfully engraft and differentiate into haematopoietic tissue in sheep fetuses remain uncertain. Here, we examined factors that might influence donor cells and recipient sheep and affect successful ES cell engraftment. We transplanted either undifferentiated monkey ES cells or ES-derived cells at an early haematopoietic differentiation stage into sheep fetuses. The latter cells were allowed to differentiate by culturing on OP9 cell layers for 6 days. Cells were transplanted into the liver or subcutaneous tissue of recipient sheep fetuses at 43 to 50 or 51 to 67 days of gestation (full term = 147 days) using ultrasound to identify the site for transplantation. After birth, monkey haematopoietic engraftment in the bone marrow was analysed in 40 lambs using colony-PCR with cells grown in methylcellulose in the presence of defined cytokines; teratoma formation was analysed by biopsy and immunohistochemistry. We found that haematopoietic engraftment was only observed when ES-derived cells at the early differentiation stage were transplanted into fetal livers at 51 to 67 days of gestation (6/9). However, teratoma formation with mature monkey tissue structures was only observed following transplantation of undifferentiated ES cells into fetal subcutaneous tissues at 43 to 50 days of gestation (4/6), but that was not observed when both types of cells were transplanted into the liver (0/18) or at 51 to 67 days of gestation (0/24). These results demonstrate that the differentiation status of the donor cells, the transplantation site, and the age of the fetus at transplantation are important factors in engraftment and differentiation into haematopoietic tissue or teratoma formation in sheep fetuses.

312 EFFECTS OF TRANSFORMING GROWTH FACTOR ALPHA AND INSULIN-LIKE GROWTH FACTOR 1 SUPPLEMENTATION ON IN VITRO MATURATION OF CANINE OOCYTES

Although in vitro maturation (IVM) of oocytes has been successfully established for many species, the efficiency of IVM in canine oocytes is still very low. As growth factors have been shown to promote oocyte maturation in some species, we investigated whether use of transforming growth factor α (TGF-a) and insulin-like growth factor 1 (IGF-1) might overcome the difficulties of achieving meiotic maturation in cultured canine cumulus-oocyte complexes (COC). Ovaries were obtained from bitches at 6 months to 7 years of age by ovariohysterectomy and were sliced repeatedly to release COC. In the first experiment, the COC were cultured at 38.8°C for 48 h in 5% CO2 in air in medium 199 supplemented with either TGF-a (0, 1, 10, or 100 ng mL–1) or IGF-1 (0, 0.5, 5, 10, or 50 µg mL–1). In the second experiment, the synergistic effect of TGF-a and IGF-1 was investigated by culturing COC in medium 199 supplemented with both TGF-a (0, 1, 10, or 100 ng mL–1) and IGF-1 (0, 0.5, 5, 10, or 50 µg mL–1). At the end of the culture period, the oocytes were denuded of cumulus cells by pipetting with a fine bore glass pipette; the denuded oocytes were then fixed in Carnoy's solution and stained with Hoechst 33342. The nuclear configuration and chromatin morphology of the oocytes were evaluated under confocal laser scanning microscopy. The cells were assigned to 1 of the following meiotic stages: germinal vesicle (GV), germinal vesicle breakdown (GVBD), metaphase I (MI), or metaphase II (MII). Data were analysed by ANOVA with Fisher's PLSD test. In experiment 1, no significant difference were observed in the rates of cells maturing to the MI and MII stages, but that in the 10 ng mL–1 of TGF-a group (56.3%) were larger than in the other treatment groups (38.8–51.0%). The frequencies of MII stage cells in the 5, 10, and 50 µg mL–1 of IGF-1 treatment groups (9.8, 13.3, and 12.2%, respectively) were significantly higher than in the 0.5 µg mL–1 of IGF-1 group and the control group (5.3 and 2.2%, respectively). In experiment 2, the frequency of MI and MII cells in the control, 1 ng mL–1 of TGF-a plus 0.5 µg mL–1 of IGF-1, 10 ng mL–1 of TGF-a plus 5 µg mL–1 of IGF-1, 10 ng mL–1 of TGF-a plus 10 µg mL–1 of IGF-1, and 100 ng mL–1 of TGF-a plus 50 µg mL–1 of IGF-1 group were 44.1, 36.1, 63.5, 70.8, and 50.8%, respectively. The frequency of MII cells in the control group and the same treatment groups were 2.8, 7.2, 10.4, 15.3, and 10.8%, respectively. Both frequencies in the 10 ng mL–1 of TGF-a plus 10 µg mL–1 of IGF-1 group were significantly higher than in the control group. The TGF-a may act in a paracrine fashion on the surrounding granulosa cells, and IGF-1 may play multiple roles in cellular metabolism, proliferation, growth, and differentiation in canine oocyte maturation, as has been reported for many other species. In conclusion, these results demonstrate that a synergistic effect between TGF-a and IGF-1 produces an increased rate of in vitro maturation to the MI and MII stages in canine oocytes.

62 EFFECTS OF VARYING GLUTATHIONE CONCENTRATIONS IN SEMEN EXTENDER ON THE QUALITY OF FROZEN–THAWED CANINE SPERM

Trans-cervical insemination (TCI) with cryopreserved semen offers a potentially effective approach for breeding canids with specific genetic traits, such as guide dogs for the blind. However, there are technical difficulties in canine sperm cryopreservation, such as the composition of semen extender. The aim of this study was to evaluate the effects of glutathione (GSH) as an antioxidant in the semen extender to improve the quality of frozen-thawed dog sperm. A Tris-egg yolk-citrate extender containing 15.7 mg mL–1 of TRIS, 8.8 mg mL–1 of citric acid, 14.1 mg mL–1 of lactose, 25.4 mg mL–1 of raffinose, 1% (vol/vol) antibiotics, and 20% (vol/vol) egg yolk in ultra-pure water was used as the base medium. Twelve ejaculates were collected from 7 dogs. Each ejaculate was divided into 2 to 5 aliquots and extended with base extender supplemented with 0, 2.5, 5, 7.5, and 10 mM GSH as first dilution. The extended semen was equilibrated for 3 h at 4°C. An equal volume of second extender was added to obtain a final concentration of 6.5% glycerol and sperm per milliliter. The sperm samples were loaded in straws and frozen at 6 cm above the surface of LN2 for 15 min in a styrene foam box and plunged into the LN2. The frozen semen was thawed for evaluation. The motility of sperm was estimated with a phase-contrast microscope and the motile patterns were classified into the following grades: progressively motile at a high speed (+++), progressively motile at a moderate and low speed (++), motile without progression (+), and immotile (–). Then, the sperm motility index (SMI) was determined from the following formula as described previously (Iritani et al., 1975), with some modifications: the percentage of (+++) sperm + the percentage of (++) sperm × 0.75 + the percentage of (+) sperm × 0.5. Sperm motility and the SMI were determined at 0, 1, 2, 3, 4, 12, and 24 h after thawing. Acrosome status was evaluated at 4 h after thawing. Lipid peroxidation (LP) levels at 0 and 12 h after thawing were used to examine the antioxidant ability of GSH. Trans-cervical insemination was carried out on 5 bitches to evaluate the fertility of GSH-treated sperm. The TCI were performed nonsurgically with a laparoscope and deposited 2 mL of semen through a catheter. Each bitch was inseminated 1 to 2 times during oestrus. Data were analysed using ANOVA with the Tukey-Kramer method. We found that the rate of (+++) sperm in the 5 mM GSH group was higher than that in the 0 mM group from 1 to 24 h after thawing (P < 0.05). The SMI was higher in the 5 and 7.5 mM GSH groups than in the 0 mM group (P < 0.05). There were no significant differences in the control and 2.5 and 10 mM GSH groups. Long-term survival was increased in the 5 mM GSH group. Acrosome integrity was higher in the GSH-treated group. The level of LP was lower in the GSH-treated groups at 0 h after thawing (P < 0.05). Trans-cervical insemination with the 5 mM GSH-treated semen resulted in the delivery of 5 pups from 2 bitches. These results indicate that the cryopreservation with 5 mM GSH can improve the motility, viability, and fertility of frozen-thawed canine sperm by its antioxidant effects on the sperm membrane.

182 EFFECTS OF MITOCHONDRIAL ACTIVITY OF INJECTED SPERM ON EARLY DEVELOPMENT IN BOVINE INTRACYTOPLASMIC SPERM INJECTION-DERIVED EMBRYOS

Intracytoplasmic sperm injection (ICSI) has become the method of choice for bovine ovum pick-up and IVF. However, there are many difficulties with the ICSI technique to obtain viable fetuses. One of the major problems associated with this technique is our lack of knowledge concerning the status of the sperm mitochondria when injected into the oocyte and its effect on embryo development. First, we examined the mitochondrial activity of sperm that had been activated by culturing with methyl-β cyclodextrin (MBCD), in ICSI and in IVF. In vitro-matured oocytes and JC1-labelled sperm were used for the ICSI and IVF. The fluorescence intensity of injected/penetrated sperm mitochondria was measured using confocal laser scanning microscopy. Then, the relative membrane potential of the mitochondria was analysed by a ratiometric method. Second, the reactive oxygen species (ROS) production and capacitation status of the sperm exhibiting normal motility and of the sperm that had been activated by culturing with MBCD were analysed. The ROS levels produced by the sperm were estimated using the luminol assay. The chlortetracycline stain was used to evaluate capacitation status of the sperm. Third, the effect of ROS produced by these sperm types upon embryogenesis following ICSI and IVF was studied. Early developing embryos were examined with a stereomicroscope for cleavage and development to the blastocyst stage after 7 days of culture. Chromosome samples stained with Giemsa solution from the blastocysts were used to analyse the chromosomal integrity. Data were analysed by t-test for Experiments 1 and 2, and ANOVA with Fisher's PLSD test for Experiment 3. The mitochondrial activity immediately after ICSI was higher than at 3 h after insemination (immediately after sperm penetration) in IVF (P < 0.05). The sperm exhibiting activation were capacitated and produced more ROS than the sperm exhibiting normal motility (P < 0.05). The rates of cleaved embryo and blastocyst after ICSI with activated sperm were the same as that in ICSI with normal motility sperm and in IVF (cleaved rate: 66.7, 71.8, and 85.0%, respectively; blastocyst rate: 24.4, 23.3, and 32.0%, respectively). However, chromosomal integrity of blastocysts derived from ICSI with activated sperm was lower than that for ICSI with normal motility sperm or for IVF (23.1, 75.0, and 63.6%, respectively; P < 0.01). In conclusion, capacitated, activated sperm induced chromosomal aberrations during early embryo development following ICSI. Conceivably, the selection of sperm exhibiting progressive motility, which is expected to be activated and to fertilize, would not always be better for early embryo development and fetal growth following ICSI due to the ROS derived from the sperm mitochondria. Injection of sperm exhibiting normal motility, or of mitochondria reduced activated sperm, could improve the quality of ICSI-derived embryos.

Acetabular and proximal femoral alignment in patients with osteoarthritis of the dysplastic hip and its influence on the progression of disease

In order to evaluate the relationship between acetabular and proximal femoral alignment in the initiation and evolution of osteoarthritis of the dysplastic hip, the acetabular and femoral angles were calculated geometrically from radiographs of 62 patients with pre-arthrosis and early osteoarthritis. The sum of the lateral opening angle of the acetabulum and the neck-shaft angle was defined as the lateral instability index (LII), and the sum of the anterior opening angle of the acetabulum and the anteversion angle of the femoral neck as the anterior instability index (AII). These two indices were compared in dysplastic and unaffected hips. A total of 22 unilateral hips with pre-arthrosis were followed for at least 15 years to determine whether the two indices were associated with the progression of osteoarthritis. The LII of the affected hips (197.4 (sd 6.0)) was significantly greater than that of the unaffected hips (1830 (sd 6.9)). A follow-up study of 22 hips with pre-arthrosis showed that only the LII was associated with progression of the disease, and an LII of 196 was the threshold value for this progression.

Effect of PVP on sperm capacitation status and embryonic development in cattle

The objective of this study was to investigate the effects of polyvinylpyrrolidone (PVP) on sperm capacitation status and embryonic development in cattle (Bos taurus). Acrosome-reacted sperm (chlortetracycline stain) and the fertilization rate after intracytoplasmic sperm injection (ICSI) were enhanced (P<0.05) when sperm were cultured in a medium containing 10% PVP. However, injection of bovine in vitro-produced (IVP) embryos with medium containing 10% PVP suppressed development of these embryos to the 2-cell, morula, and blastocyst stages and cell number at the blastocyst stage (P<0.01) but did not affect chromosomal integrity (P>0.05). Embryo developmental capacity differed (P<0.01) among PVP from three suppliers, but there were no significant differences among three solvent media. The PVP remained localized in 40.9% of PVP-injected IVP embryos. In conclusion, PVP affected the acrosome reaction and enhanced the fertilization rate after ICSI. However, PVP remained detectable in IVP embryos and suppressed their developmental capacity.

58 PRODUCTION OF CLONED BOVINE EMBRYOS DERIVED FROM AMNIOTIC CELLS OF PREGNANT COWS

Progeny tests are widely used for selection of sires for beef and dairy cattle. A less costly method might be to clone the sire candidates at their earliest developmental stage possible. To produce cloned bulls, we obtained amniotic cells as donors for nuclear transfer by transvaginal aspiration of pregnant cows. However, the collected cells may include some maternal cells. In this study, we examined collection methods to obtain only fetal cells from the collected fluid. We also examined the developmental capacity of the embryos cloned from these cells. Amniotic fluids were aspirated from pregnant cows by ultrasound-guided aspiration. We collected amniotic fluids from 27 pregnant Japanese black beef cattle (between 58 and 132 days of gestation). In Method 1, cells were recovered from the whole amniotic fluid (approximately 15 mL). In Method 2, the initial 5 mL of aspirated fluid was discarded and then the next 10 mL sample was collected. Cells were recovered from the collected fluids. The cells in the fluids were washed twice by centrifugation and then cultured in AmnioMAX™-II medium (GIBCO, Grand Island, NY, USA). After 3–4 passages, the sex of the cell lines was determined by the loop-mediated isothermal amplification (LAMP) method (Eiken Chemical Co., Ltd., Tokyo, Japan). For the cell lines that were determined as 'male' by the LAMP method we further analyzed the sex of individual cells (137–620 cells of each cell line) by fluorescent in situ hybridization (FISH) using a bovineY chromosome-specific probe (Kobayashi et al. 1998 Mol. Reprod. Dev. 51, 390–394). The percentage of male cells obtained from Methods 1 and 2 were 0–0.4% (from 4 animals) and 93.7–99.5% (from 6 animals), respectively. Then, we used confluent amniotic cells from 3 cell lines obtained by Method 2 as donor cells for nuclear transfer and examined the developmental capacity of the cloned embryos. Bovine fibroblasts cultured under serum starvation were used as a control. The cells were electrically fused (2.7 kV cm–1, 11 µs, 2 times) with enucleated bovine oocytes, and activated with a calcium ionophore and cycloheximide. They were subsequently cultured in mSOF until 168 h post-activation. The data were analyzed with Fisher's protected least-squares difference (PLSD) test following ANOVA. The rates of fusion, cleavage, and development to the blastocyst stage of the cloned embryos were the same as those of the control embryos (78% v. 81%, 75% v. 75%, and 22% v. 27%, respectively; P > 0.05). Furthermore, the rate of male blastocysts derived from the cloned embryos with the three cell lines was 95% (19/20). These results indicate that the amniotic fluids collected from pregnant cows by Method 2 contained fewer maternal cells, and that the embryos cloned from the cells developed in a manner similar to that of embryos cloned from the fibroblasts. This work was supported byWakayama Prefecture CREATE, JST.

Vortex redistribution below the first-order transition temperature in the beta-pyrochlore superconductor KOs2O6

A miniature Hall-sensor array was used to detect magnetic induction locally in the vortex states of the beta-pyrochlore superconductor KOs2O6. Below the first-order transition at T{p} approximately 8 K, which is associated with a change in the rattling motion of K ions, the lower critical field and the remanent magnetization both show a distinct decrease, suggesting that the electron-phonon coupling is weakened below the transition. At high magnetic fields, the local induction shows an unexpectedly large jump at T{p} whose sign changes with position inside the sample. Our results demonstrate a novel redistribution of vortices whose energy is reduced abruptly below the first-order transition at T{p}.

Effects of water quality on in vitro fertilization and development of bovine oocytes in protein-free medium

Examination was made of the effects of water quality in medium preparation on fertilization and early development of bovine in vitro matured (IVM) oocytes in a protein-free medium. The IVM oocytes were inseminated and cultured for 7 d in protein-free media prepared with 4 different types of water preparations: tap, deionized, twice-distilled, and purified water using the Milli-Q system (Milli-Q water). High frequencies (70 to 83%) of normal fertilization were obtained in media prepared with all types of water. However, the frequency of development to the blastocyst stage in media prepared with Milli-Q water (31 +/- 3%) was significantly higher than with the 3 other types of water (11 to 13%). Moreover, the effects of storage period of Milli-Q water on early development of bovine embryos was also examined. The frequency of development to the blastocyst stage in media prepared with Milli-Q water immediately after preparation (fresh Milli-Q water; 35 +/- 4%) was significantly higher than for Milli-Q water stored for 1 wk (18 +/- 4%) or 2 wk (18 +/- 3%). Effects of commercially available purified water on early development of bovine embryos were also examined. The frequency of development to the blastocyst stage in media prepared with Milli-Q water (33 +/- 5%) was significantly higher than for purified water purchased from 3 different suppliers (Brand A; 21 +/- 6%, Brand B; 21 +/- 2%, Brand C; 21 +/- 4%). Each water sample was analyzed by the measurement of electrical conductivity, organic compounds and/or inorganic ion and endotoxin concentrations to evaluate purity. Fresh Milli-Q water showed the lowest level of electrical conductivity and contained the lowest concentration of organic compounds. These results indicate that in vitro fertilization of bovine oocytes is not affected by the water quality in the preparation of medium; however, early development of bovine embryos is seriously affected by the purification method and the storage period of water used for medium preparation.

Geographical structure of dengue transmission and its determinants in Thailand

Expansion of dengue has been attributed to urbanization. To test this concept, we examined dengue transmission intensities in Thailand. We used the inverse of mean age of dengue haemorrhagic fever (DHF) cases as a surrogate of dengue transmission intensity (or force of infection). The transmission intensity in Bangkok decreased rapidly since the mid-1990s, to levels that are currently lower than in other regions. Regression analysis revealed that transmission intensity is highest in the Northeastern rural region, mainly due to scarcity of private water wells. Private wells reduce the need for household water containers, the major breeding sites for vectors. Cumulatively, these results show that urbanization is not necessarily associated with intense dengue transmission in Thailand. Paradoxically, the DHF incidence in Bangkok has surpassed other regions despite declines in transmission intensity. This finding implies the existence of endemic stability (i.e. low incidence of a clinical illness in spite of high transmission intensity).

effects of rattling phonons on the dynamics of quasiparticle excitation in the beta-pyrochlore KOs(2)O(6) Superconductor

Microwave penetration depth lambda and surface resistance at 27 GHz are measured in high quality crystals of KOs(2)O(6). Firm evidence for fully gapped superconductivity is provided from lambda(T). Below the second transition at T(p) approximately 8 K, the superfluid density shows a steplike change with a suppression of effective critical temperature T(c). Concurrently, the extracted quasiparticle scattering time shows a steep enhancement, indicating a strong coupling between the anomalous rattling motion of K ions and quasiparticles. The results imply that the rattling phonons help to enhance superconductivity, and that K sites freeze to an ordered state with long quasiparticle mean free path below T(p).

Isotropically gapped strong-coupling superconductivity in the beta-pyrochlore KOs2O6: evidence from penetration depth measurements

We report on measurements of the temperature dependence of the magnetic penetration depth down to 0.04 K in a high-quality sample of the beta-pyrochlore KOs2O6 (Tc=9.65 K) with a spin-frustrated lattice. We observe temperature-independent behavior below T approximately 0.3Tc, which is firm evidence for the presence of an isotropic superconducting gap in this material. In the whole temperature range the superfluid density is very well described, without the need of adjustable parameters, by a strong-coupling extension of the BCS model for an isotropic gap. Thus, the penetration depth results indicate that KOs2O6 is a strong-coupling superconductor with a fully developed energy gap. No effect of the second phase transition taking place at Tp=7.5 K was observed on the penetration depth, which suggests that the Cooper pairs remain unperturbed across this transition.

Effect of embryonic cell cycle of nuclear donor embryos on the efficiency of nuclear transfer in Japanese black cattle

In the present study, the development in vitro and in vivo of nuclear transfer (NT) embryos reconstructed with embryonic cells (blastomeres) at the 32- to 63-cell (sixth cell cycle) and 64- to 127-cell (seventh cell cycle) stages was investigated to determine the optimum range of embryonic cell cycles for yielding the highest number of identical calves in Japanese black cattle. Rates of development to the blastocyst stage (overall efficiency) were higher in the sixth cell-cycle stage (45%) than in the seventh cell-cycle stage (12%). After the transfer of the blastocysts reconstructed with blastomeres of the sixth and seventh cell cycle-stage embryos to recipient heifers, there were no differences in the pregnancy (14/35: 40% versus 3/13: 23%, respectively) or calving rates (11/39: 28% versus 3/13: 23%, respectively). These results indicate that the highest number of identical calves would be obtained by using sixth cell cycle (32- to 63-cell)-stage embryos as nuclear donors.

222 LOSS OF IMPRINTS OF PARTHENOGENETIC EMBRYONIC STEM CELLS IN MURINE CHIMERAS

Mammalian parthenotes with the 2 maternal genomes cannot develop to term. By contrast, chimeras produced by parthenogenetic and normal embryos can develop to term. However, parthenogenetic cells contribute to restricted cells and body weights of the chimeras are reduced. These effects are due to aberrant expressions of imprinted genes, with complete methylation of the maternally methylated genes and complete loss of the paternally methylated genes. On the other hand, parthenogenetic ES (PGES) chimeras show more normal tissue contribution of donor cells and body weight compared to parthenogenetic embryo (PG) chimeras. To elucidate the epigenetic mechanisms underlying this, we analyzed the epigenetic status of maternally methylated genes in murine PG and PGES chimeras. To make parthenogenetic chimeras, PG and PGES cells which express green fluorescent protein (GFP) were introduced into normal host embryos. Mouse embryonic fibroblasts (MEFs) from E13.5 chimeric fetuses were sorted by the fluorescence-activated cell sorter (FACS). Methylation status of parthenogenetic cells was analyzed by combined bisulfite restriction analysis (COBRA) and bisulfite sequencing. Methylation of maternally methylated genes, Peg1/Mest, Snrpn, and Igf 2r, was almost totally maintained in PG chimeras. Average methylatation percentages of PG-derived MEFs were 80% in Peg1/Mest, 84% in Snrpn, and 81% in Igf 2r (n = 6). In contrast, methylation in some PGES chimeras was partially reduced to normal level in all 3 genes (10–45%, n = 7). To clarify whether demethylation is correlated with expression of the imprinted genes, gene expression was analyzed by quantitative real-time RT-PCR. Among maternally imprinted genes, Peg1/Mest and Snrpn are expressed from the paternal allele, whereas Igf 2r is expressed from the maternal allele. Therefore, in parthenogenetic cells, loss of imprints is expected to up-regulate Peg1/Mest and Snrpn expression, and down-regulate Igf 2r expression. In fact, PGES-derived MEFs were up-regulated in Peg1/Mest and Snrpn expression, and down-regulated in Igf 2r expression. This study revealed that variations of imprint status were observed frequently in somatic cells of PGES cell origin. Demethylation could have occurred during establishment and/or maintenance of PGES cells. This demethylation that occurred in PGES cells could reprogram the maternally methylated imprinted genes and improve tissue contribution and body weight to normal level. The PGES cells with reprogramming ability might be utilized for fertility treatment and regenerative medicine.

69 APPLICATION OF BOVINE AMNIOTIC CELLS FOR PRENATAL GENETIC DIAGNOSIS AND NUCLEAR TRANSFER

Amniotic fluid includes many cells derived from the fetus called 'amniotic cells'. Although these amniotic cells may have much potential as a reproduction or breeding source of the animals, there has been limited study of the potential applications of these cells. We examined the potential of bovine amniotic cells for biotechnological use. Bovine amniotic cells separated from amniotic fluid obtained from a slaughterhouse were prepared for use in all experiments. First, to examine the culture condition of amniotic cells, the cells were cultured in various culture media. Cytologic normality of the cultured cells was analyzed by chromosomal examination and Papanicolaou examination. Second, to examine the potential of cultured amniotic cells for prenatal genetic diagnosis, the cells were used for sexing by PCR. The coincidence of the results with the gender of the fetus from which the cells were derived was examined. Third, we used the cultured cells as donor cells for nuclear transfer, and examined the developmental ability of reconstructed embryos. The normality of the blastocysts derived from the reconstructed embryos was examined by chromosomal examination and transplantation to the recipient heifer. Bovine amniotic cells were cultured successfully in Amnio-max C-100� (GIBCO, Grand Island, NY, USA), which is marketed as culture medium for human amniotic cells. In all cases, the sex of cultured amniotic cells analyzed by PCR was coincident with that of the fetus from which the amniotic cells were derived. The frequencies of cleavage and development to the blastocyst stage of embryos reconstructed from amniotic cells were the same as those of fetal fibroblasts. There were no differences in the normality of chromosomal number between blastocysts derived from amniotic cells and fetal fibroblasts. A blastocyst derived from amniotic cells developed into a fetus after transplantation. DNA microsatellite analysis of the fetus at Day 64 was coincident with that of the fetus from which the amniotic cells were derived. These results indicate that bovine amniotic cells can be successfully cultured in vitro, and the cultured cells precisely reflect the genetic information of the fetus from which the cells were derived. The cultured cells also have developmental ability as donor cells for nuclear transfer. Amniotic cells may have the potential for effective reproduction and breeding using genetic and biotechnological sources.

374 THE EFFECTS OF POLYVINYLPYRROLIDONE ON BOVINE SPERM FUNCTION AND EMBRYO DEVELOPMENT

In assisted reproduction by ICSI, PVP has been successfully used to replicate the viscosity of sperm solution, thus facilitating the handling and immobilization of spermatozoa. Sperm is suspended in medium containing polyvinylpyrrolidone (PVP), then injected into the oocytes together with a small amount of the medium in ICSI. However the effects of PVP on sperm function and embryo development have not been investigated in detail. In the present study, we investigated the effects of PVP solution on sperm function and embryonic development. Frozen–thawed spermatozoa from a Japanese Black bull and immature COCs from slaughterhouse bovine ovaries were used for all experiments. In experiment 1, bovine sperm was cultured in SOF or SOF containing 10% PVP. For detection of sperm acrosomal and chromatin integrity, sperm cultured in each medium were stained by the triple staining method and acridine orange after 0, 15, 30, and 60 min of culture. In experiment 2, zygotes were injected with PVP solution and cultured in vitro; subsequent cleavage and development to blastocysts were examined. In experiment 3, zygote injected with PVP solution was fixed by 4% paraformaldehyde after 1–3 h of PVP injection. The location of PVP solution in zygote was observed. In experiment 4, two-cell embryos were microinjected with a solution of dextran conjugated with fluorescein (FITC-dextran) and cultured in vitro. The location of FITC-dextran in the embryo was examined. In experiment 1, acrosome reactions of the sperm were enhanced after 15 min of incubation in PVP solution (P &lt; 0.05), but chromatin integrity of the sperm was not influenced (P &gt; 0.05). In experiment 2, PVP suppressed the development of the zygote to 2-cell, morula and blastocyst (75.0%, 35.1%, and 26.3% vs. 61.3%, 20.2%, and 12.9% for control and PVP group, respectively, P &lt; 0.05). In experiment 3, the locations of PVP solution in the zygote were observed 1–3 h after injection. In experiment 4, FITC-dextran was observed in ICM at the blastocyst stage. These findings suggest that PVP affects the acrosome but not the chromatin of sperm in ICSI. PVP solution exists locally in embryos injected and affects the developmental capacity of the embryos.

Uptake of deuterium by dead leaves exposed to deuterated water vapor in a greenhouse at daytime and nighttime

Dead leaves were exposed to deuterated water vapor (D(2)O) as a substitute of tritiated water (HTO) in a greenhouse at daytime and nighttime to examine uptake and release of tritium by dead leaves because they cover a wide area of the forest floor and are therefore a major target material to be exposed when HTO is atmospherically derived to the forest. The dead cedar needles showed faster uptake and faster release rates during and after the exposure than the fresh ones, and the equilibrium concentration of the dead cedar needles was about two times higher than the fresh ones, indicating a quick response and a high buffering potential of dead leaves. The relation between uptake of D(2)O and number of stoma was examined for dead deciduous leaves; the species with larger number of stoma accumulated more D(2)O at the daytime and nighttime exposures. However, drying of the dead leaves suppressed D(2)O uptake greatly at daytime, suggesting stomata's opening and closing controls the D(2)O uptake of dead leaves.

3 NUCLEAR REPROGRAMMING OF PORCINE FIBROBLAST CELLS BY XENOPUS EGG EXTRACTS

Much evidence indicates that somatic cells can be reprogrammed in an oocyte cytoplasm. The nuclear reprogramming consists of many unknown processes, and mechanisms underlying these processes still remain to be elucidated. Recently some reports noted that Xenopus oocytes or eggs can induce some of the reprogramming events in mammalian cells. We investigated the processes of nuclear reprogramming of porcine fibroblast cells by Xenopus egg extracts to understand how egg extracts trigger the reprogramming and/or dedifferentiation of cells. Unfertilized Xenopus eggs were collected from mature females. After removal of the jelly coat, activation was routinely achieved by calcium ionophore A23187. The eggs were immediately centrifuged and the cytoplasmic fraction was used as egg extracts. Porcine fibroblast cells were permeabilized by streptolysin O and incubated in the egg extracts under the ATP-generating system (1 mM ATP, 5 mM phosphocreatine, and 20 U/mL creatine kinase) for 30 min at 37�C or 2 h at 23�C. The incorporation of Xenopus-specific linker histone B4 into porcine fibroblasts was examined by immunofluorescence and immunobloting analysis. After collection of cells from the extracts, permeabilized membranes of the cells were resealed in culture medium containing 2 mM CaCl2 for 2 h. The cells were then incubated in DMEM with 10% fetal bovine serum (FBS) or porcine zygote medium-3 (PZM-3: Yoshioka et al. 2002 Biol. Reprod. 66, 112-119) containing 5.55 mM glucose and 5% FBS. RNAs were extracted from the cells in each culture dish and Oct-4 expression was examined by RT-PCR analysis every day until Day 8. The primers were designed to span the 99 base-pair intron region of porcine Oct-4 gene for recognizing both spliced and unspliced transcripts. The incorporation of histone B4 from Xenopus egg extracts was observed at the nuclear region of the porcine fibroblasts under both the 37�C and the 23�C conditions. Because the histone B4 incorporation was inhibited by addition of Apyrase, an ATPase, a part of reprogramming might be an ATP-dependent process. When treated cells were incubated in DMEM or PZM-3, Oct-4 expression was detected in the cells cultured in DMEM, but not in PZM-3. However, the transcripts of Oct-4 were mainly obtained in unspliced form at the earlier stage of culture (after Day 1 to Day 4 of culture), suggesting that a part of reprogramming processes by the egg extracts involves induction of dedifferention of cells or activation of a pluripotent marker gene such as Oct-4. Xenopus egg extract may provide a system to investigate the processes involving nuclear reprogramming and the pluripotent state of mammalian cells in vitro.

Mammographic density and the risk of breast cancer in Japanese women

Using an automated method for detecting mammographic mass, the authors evaluated the relation between quantitatively measured density and the risk of breast cancer in a case–control study among Japanese women. The case subjects were 146 women newly diagnosed and histologically confirmed with breast cancer at a general hospital. A total of 659 control women were selected from those who attended a breast cancer mass screening at this hospital. Significantly increased odds ratios (ORs) of breast cancer were observed for breast densities of 25–49 and 50–74%, but not for densities of 75–100% as compared with 0% in premenopausal women after controlling for covariates (ORs=4.0, 4.3, and 1.4, respectively). In postmenopausal women, ORs were significantly increased for breast densities of 25–50% (OR=3.0) and 50–100% (OR=4.2). Total breast area was significantly associated with the risk of breast cancer independent of density percent or dense area in postmenopausal women. These data suggested that mammographic density was associated with the risk of breast cancer in Japanese women as is the case in Caucasian women. However, the associations of the risk of breast cancer with breast size and a high breast density greater than 75%, needs to be confirmed in future studies.

53 CELL CYCLE SYNCHRONIZATION OF DONOR CELLS AT G1 PHASE AND DEVELOPMENTAL ABILITY OF NUCLEAR TRANSFER EMBRYOS IN MINIATURE PIGS

The cell cycle of donor cells is one of the essential factors for the success of somatic cell nuclear transfer (SCNT), and G0/G1-phase cells have been widely used as donor cells. However, cells synchronized at the G0/G1-phase also have a population of cells with cell cycles other than G0/G1-phase, and we cannot precisely know the cell cycle of donor cells being used for SCNT. In this experiment, we reconstructed SCNT embryos from donor cells that were synchronized at the G1-phase or at the G0/G1-phase and compared their developmental ability in two different culture media. Immature oocytes were isolated from ovaries collected from domestic gilts at a local slaughterhouse and were co-cultured with follicle shells for in vitro maturation (Hoshino et al. 2003 Theriogenology 59, 260). Donor cells were collected from fibroblast cells of miniature Potbelly pigs. Cells synchronized at the G1-phase were prepared shortly after dividing M-phase cells that had been synchronized using 2-methoxyestradiol, as described by Urakawa et al. (2004 Theriogenology 62, 714–728). The G0/G1 cells were also prepared from a fully confluent culture of cells. Donor cells were fused with enucleated oocytes and simultaneously activated by two electric pulses. Reconstructed embryos were cultured in two different media [Whitten and Biggers medium supplemented with 0.5 mg/mL hyaluronic acid sodium salt (WM) and porcine zygote medium-3 (PZM-3, Yoshioka et al. 2002 Biol. Reprod. 66, 112–119)] under 5% CO2 in air. Cleavage rate and development rate to the blastocyst stage were assessed after 48 and 168 hr of culture, respectively. The results are summarized in Table 1. Developmental rate to the blastocyst stage of SCNT embryos reconstructed from G1 cells and cultured in PZM-3 (40%) was significantly higher than that of embryos cultured in WM (25%). The SCNT embryos of the G1 cells showed significantly lower cleavage rate (51%) than that of the G0/G1 cells (69%). However, the developmental rates to the blastocyst stage per cleaved embryo in WM were significantly higher in G1 cells (50%) compared with G0/G1 cells (32%). In addition, the total cell number of the SCNT blastocysts was comparable between the cultures in WM (58 ± 4) and PZM-3 (46 ± 5), although the ratio of inner cell mass cells to the total cell number was significantly higher in PZM-3 (32%) compared with WM (14%). These results suggest that PZM-3 may fit with the culture of SCNT embryos, and that the G1 synchronized cells could be stably reprogrammed for early embryonic development in SCNT embryos and be useful as donor cells for analyzing the processes of nuclear reprogramming. Table 1. Development of nuclear transfer embryos reconstructed from G1 or G0/G1 cells in different culture media

171 NORMAL REPROGRAMMING OF IMPRINTING IN PARTHENOGENETIC FEMALE GERM CELLS

Mammalian parthenotes cannot develop normally to term. Mouse parthenogenetic embryos die by Day 10 of gestation. On the other hand, viable parthenogenetic chimeras were produced by normal host embryos, although parthenogenetic cells were observed in a limited number of tissues and organs and, even in these instances, their contribution was substantially reduced. This can be explained by the aberrant expressions of imprinted genes in parthenogenetic cells. In female mice, erasure of imprints occurs around the time that primordial germ cells enter the gonad, and establishment of imprints occurs in the postnatal growth phase of oogenesis. In this study, we investigated whether aberrant imprints in parthenogenetic embryonic stem (PgES) cells can be erased through the germline. Diploid parthenogenetic embryos were produced by activation of (CBA × C57BL/6-EGFP) F1 mouse superovulated unfertilized oocytes by exposure to Sr2+ and cytochalasin B. Ten parthenogenetic blastocysts were plated and three PgES cell lines were isolated. Chimeras were made by injecting 10–15 PgES cells into ICR(CD-1) mouse blastocysts. Chimeras and chimeric tissues were detected by fluorescent microscopy. In all, 173 chimeric blastocysts were transferred to 9 recipient females, and 101 live pups containing 9 female and 21 male chimeras were born. No significant growth retardation was apparent in PgES chimeras, irrespective of their degree of chimerism. In 5 male chimeras killed at 1 day postpartum (dpp), PgES cells showed a restricted tissue contribution. The contribution to lung, liver, and intestine was considerably lower than in the other tissues such as brain, heart, spleen, and kidney. PgES derived or host embryo derived non-growing oocytes were isolated from dissociated ovaries of female chimeras at 1 dpp under fluorescent microscopy. Methylation imprints in non-growing oocytes were analyzed for maternally methylated imprinted genes Peg1, Snrpn, and Igf2r by the combined bisulfite restriction analysis (COBRA). In normal oocytes, imprints are expected to be erased and these genes are unmethylated at this stage. We observed that these genes were unmethylated in both PgES derived and host embryo derived non-growing oocytes. These results suggest that aberrant imprints in PgES cells can also be erased normally through the germline.

A cohort study of chronic liver disease in an HCV hyperendemic area of Japan: a prospective analysis for 12 years

A mass screening in 1990 of H town in Japan demonstrated a high prevalence of hepatitis C virus (HCV) infection in our previous studies. The purpose of the present study was to evaluate the prognosis and natural history of liver disease among the same residents after 12 years. Of 509 residents, 69 people had died, and 55 people had moved to other regions. In all, 139 persons of the remaining 385 residing in H town were examined for liver function tests, antibodies to HCV (anti-HCV), serum HCV RNA, and hepatitis B virus surface antigen (HBsAg). The data of 14 of these 385 people were collected from medical records. The cause of death of the 69 individuals was investigated. The prognosis of liver disease could be clarified after 12 years in 222 of the 509 residents. Most of the residents with liver disease had an advanced stage of disease. Of the 69 persons who died, the mortality rate caused by liver cirrhosis or hepatocellular carcinoma (HCC) was 44 and 53%, respectively, among 25 persons with positive anti-HCV, and 19 with positive HCV RNA. One person with positive HBsAg died of HCC. Persons with chronic HCV or HBV infection had significantly higher mortality rates from liver cirrhosis and HCC than those without infection (P<0.00001). The present study suggests that early detection and treatment for HCC should be carried out as HCV carriers age. Furthermore, persistent HCV carriers should receive therapy for suppression of the development of HCC. The eradication of HCC should be considered a national goal.

Paroxysm serum from a case of Plasmodium vivax malaria inhibits the maturation of P. falciparum schizonts in vitro

In concurrent infections in vivo, the blood stages of Plasmodium vivax suppress those of Plasmodium falciparum. To see if the paroxysm (i.e. the periodic febrile episode) of P. vivax infection contributes to this suppression, sera from a P. vivax-infected volunteer were added to cultures of whole blood taken from cases of P. falciparum malaria. The crude 'rate' of schizont generation from the ring forms, measured as the percentage of all asexual parasites that were schizonts after incubation for 24 h, was similar whether the cultures contained serum samples collected during paroxysms or those collected, from the same volunteer, at other times (19.1% v. 18.9%; P=0.842). After a random-effect linear regression was used to adjust for disparities between the P. falciparum isolates, however, the degree of schizont maturation, measured as the mean number of nuclei per schizont, was significantly lower for the cultures with 'paroxysm serum' than for those with 'non-paroxysm serum' (4.8 v. 5.3; P=0.002). The proportion of schizonts considered mature was also significantly lower when 'paroxysm serum' was used (3.7% v. 6.3%: P=0.03). This appears to be the first in-vitro study in which sera collected during a paroxysm of P. vivax have been shown to inhibit the maturation of P. falciparum schizonts. The role of this mechanism in intra- and inter-specific competition is discussed.

Evaluation of styrene oligomers eluted from polystyrene for estrogenicity in estrogen receptor binding assay, reporter gene assay, and uterotrophic assay

Styrene dimers (SDs) and styrene trimers (STs) eluted a little from polystyrene have been suspected of having estrogenic activity in the Wingspread Declaration [Our Stolen Futures, 1996] despite the lack of scientific analysis. Therefore, we have studied and reported styrene oligomers to have no endocrine disrupting effects [J. Food Hygienic Soc. Japan 40 (1999) 36; 41 (2000) 109; Yuki Goseikagaka Kyokaishi 57 (1999) 58; Bunseki Kagaku 49 (2000) 493, 857; Food Chem. Toxicol. 39 (2001) 1233; 40 (2002) 129]. However, Ohyama et al. reported that certain styrene oligomers have estrogenic effects in E-SCREEN and estrogen receptor (ER) binding assay [Environ. Health Perspect. 109 (2001) 699]. Recently, several assay systems have been developed, and a few of them can show false positive reactions at the high concentrations to which test compounds are precipitated [J. Health Sci. 48 (2002) 83]. In order to assess the estrogenic effect of SDs and STs in more detail, we examined the accuracy of the binding assay system and tested SDs and STs by three types of ER binding assay. In one ER binding assay, the same method that Ohyama et al. performed, SDs and STs showed a little estrogenic activity at high concentration; they did not dissolve, but this assay system tended to detect false positive effects at high concentration. In contrast, in the other assay systems, SDs and STs did not show any binding affinity to ER. In addition, luciferase reporter gene assay in HeLa cells transfected with ER expression plasmid and reporter plasmid, as a newly developed standard assay, and immature rat uterotrophic assay were conducted. In these tests, styrene oligomers showed no estrogenic activity.

The possible intraspousal transmission of HCV in terms of lichen planus

Lichen planus (LP), common mucocutaneous disorder, involves not only oral mucosa and skin but genitalia membrane. LP is frequently seen in patients with HCV infection. This study evaluated patients with HCV-associated oral lichen planus (OLP) for vulvar and vaginal LP involvement, and the possible intraspousal transmission of HCV. We examined a total of 24 female Japanese patients with OLP for genitalia LP: 14 OLP-HCV positive and 10 OLP-HCV negative. All subjects were evaluated for genital LP by a gynecologist. All 24 subjects and 10 of the husbands were tested for anti-HCV and serum HCV RNA. Vulvar LP was observed in 10 (41.7%) of 24 patients with OLP. Vulvar LP in 14 (OLP-HCV positive) and 10 patients (OLP-HCV negative) were observed in 42.9 and 40%, respectively. There were no significant differences (age, sites of OLP, blood transfusion, HCV infection, and degree of liver diseases) between the vulvar LP and non-vulvar LP patients. Two spouses of 10 married couples were shown to be infected with HCV. In one couple with HCV infection, the wife and husband had also erosive OLP, the wife had erosive vulvar LP. In conclusion, the majority of OLP patients suffered from genitalia LP in Japan. Clinicians should follow the OLP patients with sufficient attention to the presence of extraoral manifestations. These data may suggest the occurrence of intraspousal transmission of HCV through erosive vulvar LP.

High prevalence of anticardiolipin antibodies in patients with HCV-associated oral lichen planus

Hepatitis C virus (HCV) has been linked to extrahepatic manifestations such as oral lichen planus (OLP). In addition, anticardiolipin antibodies (aCL) and cryoglobulin have been demonstrated in chronic hepatitis C. The aim of this study was to investigate these prevalences in patients with HCV-associated OLP. The prospective study investigated the role of these factors in 133 subjects: 28 with OLP-HCV(+) (group 1), 22 with OLP-HCV(-) (group 2), 33 without OLP-HCV(+) (group 3), and 50 healthy volunteers matched for age and sex served as control group (group 4). Levels of immunoglobulin G (IgG) and IgM aCL antibodies, and cryoglobulin in serum were evaluated by enzyme-linked immunosorbent assay. The prevalence of aCL in groups 1, 2, 3, and 4 were 32.1, 18, 36.3, and 8%, respectively. The positive rate of aCL was significantly higher in groups 1 and 3 than that in the control group (group 1; p=0.02 vs. the control group, group 3; p<0.01 vs. the control group). There were no significant differences in cryoglobulin among the groups. The findings of the present study showed a high prevalence of IgG and IgM aCL in the serum of patients with HCV infectious diseases. A positive factor for aCL was determined by age, sex, the presence of OLP, and HCV infection.

A case of muscular hamartoma of the breast

We describe a 74-year-old female presenting with a right breast mass. She had found the mass on self-examination. Physical examination revealed a 2.2 x 2.5 cm, firm, smooth, and mobile lump in the upper medial portion of the right breast. Mammography revealed a well marginated, oval-shaped, and isodense nodule. Calcification was not evident. On ultrasonography, the lesion was 17 x 18 x 9 mm and located 5 mm below the overlying skin. Excisional biopsy under local anesthesia was performed. The tumor was easily excised. Histopathologically, the lesion was composed of intersecting bundles of spindle-shaped smooth muscle cells, and involved peripheral ducts and fat tissue. Immunohistochemical staining showed positivity for alpha-smooth muscle actin (SMA), but was negative for S-100 protein, myoglobin, keratin, and vimentin. From these findings a muscular hamartoma of the breast, a rare subtype of hamartoma, was diagnosed.

Time course profile and cell-type-specific production of monokine induced by interferon-gamma in Concanavalin A-induced hepatic injury in mice: comparative study with interferon-inducible protein-10

BACKGROUND

We have previously shown that interferon-inducible protein-10 (IP-10), a chemokine for activated lymphocytes, was specifically induced in the liver of Concanavalin A (Con A)-treated mice. The aim of this study was to investigate the time course profile and cell-type-specific hepatic production of monokine induced by interferon-gamma (MIG), a chemokine which shares its receptor and most of its activity with IP-10, in Con A-treated mice and to compare them with those of IP-10.

METHODS

Hepatic mRNA expression of MIG and IP-10 was studied by means of Northern blot analysis and in situ hybridization in Con A-treated mice. The levels of MIG and IP-10 in the serum and culture supernatants of murine hepatoma-, hepatic sinusoidal endothelial cell-, hepatic stellate cell- and macrophage-derived cell lines were determined by means of specific enzyme-linked immunosorbent assays.

RESULTS

The serum level of MIG slowly reached a maximum at 12 h after Con A injection and remained elevated for a long time, whereas that of IP-10 reached a maximum at 3 h and declined quickly, a finding supported by Northern blot analysis. Using in situ hybridization, the mRNA of MIG as well as IP-10 was found to be expressed in hepatocytes and hepatic non-parenchymal cells. Similar to IP-10, MIG was produced by hepatoma-, hepatic sinusoidal endothelial cell-, hepatic stellate cell- and macrophage-derived cell lines in vitro.

CONCLUSIONS

Although both MIG and IP-10 were produced by hepatocytes and hepatic non-parenchymal cells in Con A-treated mice, the time course profile of MIG was distinguishable from that of IP-10. The fact that hepatic MIG and IP-10 were produced sequentially in this hepatitis model may suggest that a non-redundant role is played by these two chemokines in the process of hepatic necro-inflammation.