Differential dependencies on [Ca2+] and temperature of the monolayer spontaneous curvatures of DOPE, DOPA and cardiolipin: effects of modulating the strength of the inter-headgroup repulsion.

Biomembranes assume nonlamellar structures in many cellular events, with the tendency of forming a nonlamellar structure quantified by the monolayer spontaneous curvature, C(0), and with many of these events involving the acts of Ca(2+). Despite this biologically important intimacy, how C(0) is affected by [Ca(2+)] is unknown. In this study, we use the X-ray diffraction technique and the reconstruction of electron density profiles to measure the C(0)s of a zwitterionic phospholipid, DOPE, and two anionic phospholipids, DOPA and 18 : 1 (9Z) cardiolipin, at temperatures from 20 °C to 40 °C and [Ca(2+)]s from 0 mM to 100 mM; these phospholipids are chosen to examine the contributions of the electric charge density per molecule. While showing a strong dependence on temperature, C(0,DOPE) is nearly independent of [Ca(2+)]. In contrast, C(0,DOPA) and C(0),cardiolipin are almost unresponsive to the temperature change but affected by the [Ca(2+)] variation; and C(0,DOPA) varies with [Ca(2+)] ∼1.5 times more strongly than C(0,cardiolipin), with the phase preferences of DOPA and cardiolipin shifting to the H(II) phase and remaining on the Lα phase, respectively, at [Ca(2+)] = 100 mM. From these observations, we reveal the effects of modulating the strength of the inter-headgroup repulsion and discuss the mechanisms underlying the phase behaviour and cellular functions of the investigated phospholipids. Most importantly, this study recognizes that the headgroup charge density is dominant in dictating the phase behaviour of the anionic phospholipids, and that the unique molecular characteristics of cardiolipin are critically needed both for maintaining the structural integrity of cardiolipin-rich biomembranes and for fulfilling the biological roles of the phospholipid.

Synergistic effect of trichostatin A and scriptaid on the development of cloned rabbit embryos.

The first successful rabbit SCNT was achieved more than one decade ago, yet rabbits remain one of the most difficult species to clone. The present study was designed to evaluate the effects of two histone deacetylase inhibitors (HDACis), namely trichostatin A (TSA) and scriptaid (SCP), on cloning efficiency in rabbits. The in vitro development, acetylation levels of histone H4 lysine 5 (H4K5), and octamer-binding transcription factor 4 (Oct-4) expression patterns of cloned embryos were systemically examined after various HDACi treatments. Supplementation of TSA (50 nM) or SCP (250 nM) in the culture medium for 6 hours improved blastocyst development rates of cloned embryos compared with the treatment without HDACi. The combined treatment with TSA (50 nM) and SCP (250 nM) further enhanced morula (58.6%) and blastocyst (49.4%) rates in vitro. More importantly, compared with single HDACi treatments, embryos with the combined treatment had a higher level of H4K5 and an increased total cell number (203.7 ± 14.4 vs. 158.9 ± 9.0 or 162.1 ± 8.2; P < 0.05) with a better Oct-4 expression pattern in hatching blastocysts, indicating substantially improved embryo quality. This was apparently the first report regarding Oct-4 expression in cloned rabbit embryos. We inferred that most cloned rabbit embryos had an aberrant inner cell mass (ICM) structure accompanied with abnormal spatial distribution of Oct-4 signals. This study demonstrated a synergistic effect of TSA and SCP treatments on cloned rabbit embryos, which might be useful to improve cloning efficiency in rabbits.

Detection of multiple genotypes of calicivirus infection in asymptomatic swine in Taiwan.

Noroviruses (NoVs) and sapoviruses (SaVs) of the family Caliciviridae are emerging enteric pathogens in humans and animals. Recent detection of genogroup II norovirus (GII NoV) RNA from swine raises public health concerns about zoonotic transmission of porcine NoVs to humans. However, few papers reported genotype distributions and epidemiological features in swine farms and their genetic relationship to human strains, which was the objective of our study. This study investigated the epidemiological features and genotypes of caliciviruses in swine farms using 533 pig faecal samples from six farms in central and southern Taiwan, tested for viral RNA using RT-PCR targeting the conserved polymerase gene. NoVs and SaVs were detected with a positive rate of 7.1% and 0.6%, respectively. To confirm the positive rate of NoVs, 255 pig faecal samples from two farms in central Taiwan were tested with primer pairs targeting the partial capsid gene of GII, and 32.3% of the positive rate was found. Furthermore, the results from the capsid region suggested a higher positive rate of 41.7% in winter than 26.4% in summer with statistical significance (P < 0.05). Sequence analysis showed 29 strains belonging to GII.4 (human) and nine strains belonging to GII.11 (swine) identified based on the partial polymerase gene. Additional genotypes clustered with GII.2 (human) and GII.18 (swine) were also characterized based on the partial capsid gene. SaVs detected in porcine faecal samples belonged to genogroup III (GIII), which clustered with the PEC-Cowden strain. Our study demonstrated the presence of multiple genotypes of both human and porcine NoVs infecting swine of various ages asymptomatically. Although the zoonotic potential of detected human NoVs in swine was not conclusive owing to the lack of local human faecal samples, our study revealed the importance of monitoring emerging strains in swine to mitigate the potential impact of recombinant NoVs infecting the human population.

Orally administrable enterotoxigenic Escherichia coli vaccine encapsulated by ethylcellulose powder dispersion.

To overcome the limitations of injection administration to vaccinate neonatal piglets against diarrheal disease, an oral vaccine needs to be developed. Enteric microspheres of oral vaccines were developed by a co-spray drying process based on formalin-inactivated enterotoxigenic Escherichia coli antigens with various encapsulating materials. The encapsulating efficiencies of ECN7m, ECN14m and ECN22m (vaccine microsphere formulations) tested by extraction procedure are high, more than 85%. To assess enteric characteristics, an in vitro dissolution test was performed with microspheres. Formulations with ethylcellulose ECN14m and ECN22m allow controlled release in a neutral or basic environment and resisted acid damage. In all cases, 95% of the E. coli protein was released within 2 h at pH 6.8-7, but there was no release at pH 1.5-2. However, ECN7m was less acid-resistant and had lower release at low pH. In animal immunization tests, oral immunization with microspheres of formulations ECN14 and ECN22m effectively evoked both systemic IgG and mucosal IgA responses against E. coli whole cell antigens in mice. In the mice challenge test, orally administrable ECNm14 (12 mg) or ECN22m (12.6 mg) vaccine (i.e., encapsulating 3.0x10(9) cfu inactive bacterial mass) provided good protection from infection in animals.

Left atrial and ventricular ball thrombi complicating rheumatic heart disease with combined mitral and aortic stenosis.

A 42-year-old woman with chronic mitral stenosis was admitted for progressive dyspnea, palpitation, and weakness of lower extremities. Echocardiography revealed rheumatic, thickened, and stenotic mitral and aortic valves, and two free-floating ball thrombi were detected in the left atrium and ventricle, respectively. She died suddenly the next day, probably due to mitral or aortic outflow obstruction by the ball thrombi. We believe that the occurrence of free-floating ball thrombi in both the left atrium and left ventricle concomitantly has never been reported.

Acute myocardial infarction after upper gastrointestinal gastroscopy.

We describe a patient with gastric ulcer confirmed by upper gastrointestinal endoscopy who developed an acute Q wave myocardial infarction involving both the anterior and inferior wall shortly after the procedure. This life-threatening complication of gastroendoscopy was clearly demonstrated through studies of electrocardiogram, cardiac enzymes, echocardiogram and cardiac catherterization. We suggest that preventive measures should be implemented so that endoscopy can be performed under optimal conditions, especially for elderly patients with history of heart disease.

Once-a-month treatment with a combination of mifepristone and the prostaglandin analogue misoprostol.

In this two centre study, the efficacy of 200 mg mifepristone orally followed 48 h later by 0.4 mg misoprostol orally for menstrual regulation was investigated. The dose of mifepristone was taken the day before the expected day of menstruation. Each volunteer was planned to participate for up to 6 months. A plasma beta human chorionic gonadotrophin (HCG) was measured on the day of mifepristone intake. The study was disrupted prematurely due to low efficacy. In 125 treatment cycles the overall pregnancy rate was 17.6% (22 pregnancies) and the rate of continuing pregnancies (failure) was 4.0%. Eight women discontinued the study due to bleeding irregularities which were seen in 15 cycles (12%). These effects on bleeding pattern made the timing of treatment day difficult. Late luteal phase treatment with a combination of mifepristone and misoprostol is not adequately effective for menstrual regulation.

PIP: A 2-center study was undertaken to examine the efficacy, safety and acceptability of a once-a-month administration of a combination of 200 mg mifepristone and 0.4 mg misoprostol for menstrual regulation in the late luteal phase. About 24 women from Shanghai and 8 from Stockholm were administered 200 mg mifepristone taken orally before or on the day of menstruation, followed by 0.4 mg misoprostol taken orally after 48 hours. Urine samples were collected during 3 days before to 4 days after ovulation for an analysis of luteinizing hormone. In addition, a plasma beta human chorionic gonadotrophin was measured immediately before intake of mifepristone. Volunteers were to participate for 6 months, but the study was disrupted prematurely due to low efficacy. In 125 treatment cycles, the total pregnancy rate was 17.6% (22 pregnancies) and the failure pregnancy rate was 4.0%. Discontinuation of the study among 8 women was due to bleeding disturbances seen in 15 cycles (12%). In conclusion, late luteal phase treatment with a combination of mifepristone and misoprostol was not effective enough to be used for menstrual regulation.

Persistence of porcine reproductive and respiratory syndrome virus in intensive farrow-to-finish pig herds.

An epidemiological study of porcine reproductive and respiratory syndrome (PRRS) within pig herds was conducted in 8 intensive farrow-to-finish pig farms. Persistence of PRRS virus (PRRSV) in pig herds was demonstrated by regular postmortem examination on 2 farms for a period of 2 y. Virus isolation and serum neutralization (SN) tests were performed on the sera collected from 9 groups of pigs (10 pigs/group) of various ages on 8 pig farms. Except for 1 farm, isolation rates of PRRSV reached the highest level of 70 to 100% of pigs 6 to 8 wk of age, which coincided with the lowest levels of maternal immunity. In 1 pig herd, sows (39 in total) with SN titers of < or = 1:2, 1:4-1:8, and > or = 1:16 were designated as groups 1, 2, and 3, respectively. Sera were obtained from their progeny (3 pigs randomly selected from each litter) at various ages from 0 to 22 weeks. A positive correlation (r = 0.377, P < 0.001) between the SN titers of sows and those of their progeny (1-week-old piglets) was observed. Pigs at the age of 6 wk, only 7.9% of group 1 pigs compared to 72.4% of group 3 pigs were seropositive. A significant difference (P < 0.01) in the percentage of pigs with PRRSV viremia among the 3 groups was observed, with the lowest level found in group 3 pigs. The isolation rates of PRRSV from serum reached the maximum at the age of 9 wk for all 3 groups. The results indicated that passively acquired serum antibodies conferred a protective effect for piglets; however, loss of passive immunity at various ages of pigs produced susceptible pigs that resulted in PRRSV persistence in the pig herds. Pigs 6 to 9 weeks old were the major reservoir for PRRSV in farrow-to-finish pig herds.

Ultrasound diagnosis of rudimentary uterine horn pregnancy in fourteen weeks of gestation: a case report.

Pregnancy in a rudimentary uterine horn is rare. Rupture tends to occur in the second trimester, and results in maternal morbility and mortality. Although the diagnosis prior to rupture is difficult, early detection is essential in avoiding a fatal outcome. An asymptomatic case of pregnancy in the rudimentary horn of a bicornuate uterus prior to rupture is presented. This report is to emphasize the important value of sonography for early detection of the prerupture of the rudimentary pregnancy.

Isolation and identification of swine rotavirus in Taiwan.

Large numbers of viral particles resembling rotavirus were detected with negative stained electron microscopy in bacteria free fecal filtrate obtained from 10-day old diarrheal suckling piglets of a conventional pig farm in Taiwan. The clinical signs of vomiting and diarrhea were reproduced in colostrum deprived piglets artificially infected with the fecal filtrates. Rotavirus particles persisted in the fecal samples after two in vivo serial passages, and was not seen in the uninfected control animal. The Cytoplasm of infected jejunal and ileal enterocyte fluoresced when standard anti-porcine rotavirus conjugate was applied in an direct immunofluorescent staining test. In the experimentally infected piglets, moderate villous atrophy of the small intestine was the main microscopic lesion observed. The virus was identified by the above evidence to be rotavirus.