OGD/R-induced ferroptosis and pyroptosis in retinal pigment epithelium cells: Role of PLD1 and PLD2 modulation

This study investigated the role of phospholipase D (PLD) in retinal ischemia-reperfusion (I/R) injury using an oxygen-glucose deprivation/reperfusion (OGD/R) model commonly used in retinal I/R injury research. To create an in vitro cellular I/R model, pharmacological inhibitors and small interfering RNA (siRNA) were used to target PLD1 and PLD2 in retinal pigment epithelial (RPE) cells. Treatment with PLD inhibitors and siRNA reduced reactive oxygen species (ROS) and malondialdehyde (MDA) induced by OGD/R in RPE cells and increased the levels of superoxide dismutase (SOD) and glutathione (GSH), indicating a reduction in oxidative damage and improvement in the antioxidant system. Next, we showed that inhibiting PLD1 or PLD2 reduced intracellular iron levels and lipid peroxidation, which are critical factors in ferroptosis. Additionally, PLD1 and PLD2 modulated the expression of proteins involved in the regulation of ferroptosis, including GPX4, SLC7A11, FTH1, and ACSL4. We also investigated the roles of PLD1 and PLD2 in preventing pyroptosis, another form of programmed cell death associated with inflammation. Our study found that OGD/R significantly increased the production of pro-inflammatory cytokines and activated caspase-1, NLRP3, ASC, cleaved-caspase 1 (C-caspase-1), and GSDMD-N in RPE cells, indicating pyroptosis induction. However, PLD1 and PLD2 inhibition or knockdown significantly inhibited the production of pro-inflammatory cytokines and activation of the NLRP3 inflammasome, Taken together, our findings support the hypothesis that the PLD signaling pathway plays a key role in OGD/R-induced ferroptosis and pyroptosis induction and may be a potential therapeutic target for preventing or treating retinal dysfunction and degeneration.

Adiposity Reduction by Cucumis melo var. gaettongchamoe Extract in High-Fat Diet-Induced Obese Mice

This study investigated the anti-obesity effects of Cucumis melo var. gaettongchamoe (CG) in mice fed a high-fat diet (HFD). The mice received CG water extract (CGWE) treatment for 8 weeks, and changes in body weight and serum lipid levels were analyzed. The HFD + vehicle group showed a significant increase in body weight compared to the control group, while the HFD + CGWE and HFD + positive (orlistat) groups exhibited reduced body weight. Lipid profile analysis revealed lower levels of total cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein cholesterol in the HFD + CGWE group compared to the HFD + vehicle group. The HFD + vehicle group had increased abdominal fat weight and fat content, whereas both HFD + CGWE groups showed significant reductions in abdominal fat content and adipocyte size. Additionally, CGWE administration downregulated mRNA expression of key proteins involved in neutral lipid metabolism. CGWE also promoted hepatic lipolysis, reducing lipid droplet accumulation in hepatic tissue and altering neutral lipid metabolism protein expression. Furthermore, CGWE treatment reduced inflammatory mediators and suppressed the activation of the mitogen-activated protein kinase pathway in hepatic tissue. In conclusion, CGWE shows promise as a therapeutic intervention for obesity and associated metabolic dysregulation, including alterations in body weight, serum lipid profiles, adipose tissue accumulation, hepatic lipolysis, and the inflammatory response. CGWE may serve as a potential natural anti-obesity agent.

A Comparative Study on Photo-Protective and Anti-Melanogenic Properties of Different Kadsura coccinea Extracts

Kadsura coccinea (KC), a beneficial plant for human health, has been used for centuries in China, Thailand, and Korea in folk medicine and food. There is evidence supporting the biological effects of highly bioactive ingredients in KC such as lignans, triterpenoids, flavonoids, phenolic acids, steroids, and amino acids. In this study, we aimed to explore the effects, functions, and mechanisms of the extracts from KC root (KCR), stem (KCS), leaf (KCL), and fruit (KCF) in UVA and UVB-irradiated keratinocytes and α-melanocyte stimulating hormone (α-MSH)-stimulated melanocytes. First, the total polyphenol and flavonoid contents of KCR, KCS, KCL, and KCF and their radical scavenging activities were investigated. These parameters were found to be in the following order: KCL > KCR > KCS > KCF. UVA and UVB-irradiated keratinocytes were treated with KCR, KCS, KCL, and KCF, and keratinocyte viability, LDH release, intracellular ROS production, and apoptosis were examined. Our results demonstrated that KC extracts improved keratinocyte viability and reduced LDH release, intracellular ROS production, and apoptosis in the presence UVA and UVB irradiation. The overall photoprotective activity of the KC extracts was confirmed in the following order: KCL > KCR > KCS > KCF. Moreover, KC extracts significantly decreased the intracellular melanin content and tyrosinase activity in α-MSH-stimulated melanocytes. Mechanistically, KC extracts reduced the protein and mRNA expression levels of tyrosinase, tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2) in α-MSH-stimulated melanocytes. In addition, these extracts markedly downregulated myophthalmosis-related transcription factor expression and cAMP-related binding protein phosphorylation, which is upstream of the regulation of Tyrosinase, TRP-1, and TRP-2. The overall anti-melanogenic activity of the KC extracts was established in the following order. KCL > KCR > KCS > KCF. Overall, the KC extracts exert photoprotective and anti-melanogenic effects, providing a basis for developing potential skin-whitening and photoprotective agents.

Genome-wide analysis in 756,646 individuals provides first genetic evidence that ACE2 expression influences COVID-19 risk and yields genetic risk scores predictive of severe disease

SARS-CoV-2 enters host cells by binding angiotensin-converting enzyme 2 (ACE2). Through a genome-wide association study, we show that a rare variant (MAF = 0.3%, odds ratio 0.60, P=4.5×10^-13) that down-regulates ACE2 expression reduces risk of COVID-19 disease, providing human genetics support for the hypothesis that ACE2 levels influence COVID-19 risk. Further, we show that common genetic variants define a risk score that predicts severe disease among COVID-19 cases.

A catalog of associations between rare coding variants and COVID-19 outcomes

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease-19 (COVID-19), a respiratory illness that can result in hospitalization or death. We investigated associations between rare genetic variants and seven COVID-19 outcomes in 543,213 individuals, including 8,248 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome-wide or when specifically focusing on (i) 14 interferon pathway genes in which rare deleterious variants have been reported in severe COVID-19 patients; (ii) 167 genes located in COVID-19 GWAS risk loci; or (iii) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, with results publicly browsable at https://rgc-covid19.regeneron.com.

Steroid plus antiviral treatment for Bell's palsy

OBJECTIVES

The effectiveness of antiviral agents for the treatment of Bell's palsy is uncertain. We evaluated whether a steroid with an antiviral agent (S + A group) provided better recovery outcomes than a steroid alone (S group) in patients with Bell's palsy.

SUBJECTS AND DESIGN

A total of 1342 patients diagnosed with Bell's palsy who visited the Kyung Hee Medical Center in Seoul, Korea, from 2002 to 2012 were included in this study. Patients in the S + A group were treated with prednisolone and antiviral agents (n = 569) and those in the S group with prednisolone alone (n = 773). Outcomes were measured using the House-Brackmann (HB) scale according to age, initial disease severity, electroneurography (ENoG) findings and underlying comorbidities.

RESULTS

The rate of recovery (HB grades I and II) with initially severe Bell's palsy (HB grades V and VI) was higher in the S + A than in the S group (P = 0.001). However, the rates of recovery were similar with initially moderate palsy (HB grades II-IV) (P = 0.502). In patients classified according to age and ENoG-determined severity of palsy, the overall recovery rate was higher in the S + A than in the S group, but the differences were not statistically significant (P > 0.05 for both). The recovery rate without diabetes mellitus (DM) and hypertension (HTN) was higher in the S + A group than in the S group (P = 0.031). But in the patients with HTN and DM, the difference in recovery rates between the S + A and S groups was not statistically significant (P = 0.805).

CONCLUSIONS

Treatment with a steroid plus antiviral agent resulted in significantly higher recovery rates than steroid therapy alone in patients with initially severe Bell's palsy and without either HTN or DM, and a nonsignificant trend towards higher recovery rates in all patients with Bell's palsy in this study. Antiviral agents may therefore help in the treatment of Bell's palsy.

Human insulin secreted from insulinogenic xenograft restores normoglycemia in type 1 diabetic mice without immunosuppression

In the present study, we examined the therapeutic potential of human amnion-derived insulin-secreting cells for type 1 diabetes. Human amniotic mesenchymal stem cells (hAMs) were isolated from amnion and cultivated to differentiate into insulin-secreting cells in vitro. After culture in vitro, the differentiated cells (hAM-ISCs) were intensively stained with dithizone and secreted insulin and c-peptide in a high-glucose-dependent manner. They expressed mRNAs of pancreatic cell-related genes, including INS, PDX1, Nkx6-1, NEUROG3, ISL1, NEUROD1, GLUT1, GLUT2, PC1/3, PC2, GCK, PPY, SST, and GC, and were positive for human insulin and c-peptide. Transplantation of hAM-ISCs into the kidneys of mice with streptozotocin-induced diabetes restored body weight and normalized the blood glucose levels, which lasted for 210 days. Only human insulin and c-peptide were detected in the blood of normalized mice after 2 months of transplantation, but little mouse insulin and c-peptide. Removal of graft-bearing kidneys from these mice resulted in causing hyperglycemia again. Human cell-specific gene, hAlu, and human pancreatic cell-specific genes, insulin, PDX1, GLUT1, GLP1R, Nkx6-1, NEUROD1, and NEUROG3, were detected in the graft-bearing kidneys. Colocalization of human insulin and human nuclei antigen was also observed. These results demonstrate that hAMs could differentiate into functional insulin-secreting cells in vitro, and human insulin secreted from hAM-ISCs following transplantation into type 1 diabetic mice could normalize hyperglycemia, overcoming immune rejection for a long period.

Effect of precursor ratio on the structural properties of ZnO thin films deposited by low pressure MOCVD

The effect of precursor ratio (H2O/DEZ) on the texture orientation, surface morphology, optical transparency and electrical resistivity of ZnO thin films deposited by MOCVD was investigated. Deposition temperature and pressure were fixed at 120 degrees C and 0.67 torr, respectively. The precursor ratio was varied between 0.1 and 4. It was found that the texture orientation changed from (0002) to (1120) with increase of the precursor ratio. (1120) textured film shows well facetted tetrapod like rough surface morphology, which scatters the incident light very effectively. The electrical resistivity was in the range of about 0.1 omega cm in the undoped state, which was found to decrease with increase of the film thickness and decrease of the precursor ratio.

Insulin-like growth factor 2 enhances insulinogenic differentiation of human eyelid adipose stem cells via the insulin receptor

OBJECTIVES

Previously, we have isolated stem cells (HEAC) from human eyelid adipose tissue and functionally differentiated them into insulin-secreting cells. In the present study, we examined whether insulin family members might influence insulinogenic differentiation of HEAC.

MATERIALS AND METHODS

Following culture in differentiation media containing insulin family member or not, cells were examined for gene expression, protein expression and, particularly, insulin and C-peptide secretion, in response to high glucose challenge. Using antibodies against the specific receptor, target receptor mediating effect of the insulin family member was investigated.

RESULTS

Insulin treatment during culture had little effect on either insulin or C-peptide secretion from HEAC, against high glucose challenge after culture. However, insulin-like growth factor (IGF) 1 treatment decreased both secretions, and interestingly, IGF2 greatly increased the secretions. HEAC treated with IGF2 had strong expression of Pdx1, Isl1, Pax6 and PC1/3 genes, and distinct staining after insulin and C-peptide antibodies, and dithizone. IGF2-enhanced insulinogenic differentiation was totally blocked by antibody against insulin receptor (IR), but not by anti-IGF1 receptor (IGF1R). Differentiated HEAC expressed both IR and IGF1R genes, whereas they expressed neither IGF2 nor IGF2R genes.

CONCLUSIONS

From these results, it is suggested that IGF1 might inhibit insulinogenic differentiation of HEAC, whereas IGF2 enhances differentiation, and that enhancement of IGF2 appeared to be mediated via IR.

Antimicrobial resistance of enterococci isolated from mastitic bovine milk samples in Korea

The aim of this study was to determine the antimicrobial resistance of various species of enterococci isolated from mastitic bovine milk samples. A total of 105 enterococci isolates were examined: Enterococcus faecalis (n = 47), Enterococcus faecium (n = 39), Enterococcus gallinarum (n = 6), Enterococcus avium (n = 6), Enterococcus hirae (n = 5) and Enterococcus durans (n = 2). All the isolates were susceptible to ampicillin, gentamicin and vancomycin, and only a single E. hirae isolate was resistant to ampicillin. In general, the most frequently observed resistance among the enterococcal isolates was to tetracycline (69.5%), followed by penicillin (64.7%), erythromycin (57.1%) and cephalothin (44.7%). A similar antimicrobial resistance pattern was observed among individual species except E. durans, which exhibited only tetracycline resistance. Resistance observed among isolates of E. hirae and E. gallinarum was almost as high as E. faecium and E. faecalis. Of 105 isolates, only six (5.7%) strains of E. faecium were susceptible to all the antimicrobials tested and about 52% (55/105) showed resistance to more than three antimicrobials. The most common multiple resistance pattern was penicillin, tetracycline and erythromycin, which was observed in 32 of 105 (30.4%) isolates. This study demonstrates that enterococcal isolates belonging to minor species showed antimicrobial resistance rates as high as those of E. faecium and E. faecalis, and that monitoring of antimicrobial resistance should not be restricted only to those two major species.

Survival rate of H5N1 highly pathogenic avian influenza viruses at different temperatures

The survival rate of Korean H5N1 highly pathogenic avian influenza (HPAI) viruses was investigated at different temperatures under the laboratory conditions. The estimated survival days for a starting viral concentration of 10(6.5) 50% egg infectious dose/0.1 mL were 930, 1,042, and 3,213 d at 4 degrees C; 226, 232, and 293 d at 20 degrees C; and 51, 55, and 58 d at 30 degrees C for A/chicken/Korea/ES/03, A/chicken/Korea/IS/06, and A/chicken/Korea/Gimje/08 (Gimje/08) viruses, respectively. The stability of the Gimje/08 virus was statistically significant compared with the other 2 viruses except for the data between Gimje/08 and A/chicken/Korea/IS/06 virus at 30 degrees C. This result indicated that the survival rate of 3 Korean HPAI viruses is different at various temperatures, which might have partially influenced the large scale of HPAI outbreak in Korea in 2008.

Antibiogram and coagulase diversity in staphylococcal enterotoxin-producing Staphylococcus aureus from bovine mastitis

We investigated antibiogram and coagulase gene diversity in staphylococcal enterotoxin (StE)-producing Staphylococcus aureus isolated from raw milk samples of cows infected with mastitis from 140 dairy farms in Korea between 1997 and 2004. Of the 696 Staph. aureus isolates collected in this study, 164 isolates (23.6%) produced one or more staphylococcal enterotoxins (A to D), and 19 isolates (2.7%) were methicillin-resistant. The percentage of StE-producing Staph. aureus (SES) isolates resistant to methicillin, kanamycin, neomycin, amikacin, and tetracycline was greater than that of non-SES. Ten coagulase genotype patterns were observed, including 4 main types comprising I (25.4%), II (13.9%), VII (13.2%), and VIII (17.8%). More than 4 Staph. aureus types were isolated from each of 82 dairy farms in different geographic locations, and only 1 coagulase genotype pattern was observed in 39 of the herds (47.6%). There was no significant correlation between coagulase genotypes harbored by Staph. aureus and their specific StE type. The percentage of isolates producing major StE types (A, B, AC, and ABCD) and being resistant to cephalothin and methicillin was greater among the Staph. aureus isolates with the 4 predominant coagulase genotypes (I, II, VII, and VIII) than among the isolates harboring the 6 rare coagulase types (III, IV, V, VI, IX, and X). Based on coagulase gene polymorphisms, our data indicate that a broad distribution of identical or closely related enterotoxin-producing Staph. aureus strains seem to contribute to bovine mastitis in the Republic of Korea.

Efficient association study design via power-optimized tag SNP selection

Discovering statistical correlation between causal genetic variation and clinical traits through association studies is an important method for identifying the genetic basis of human diseases. Since fully resequencing a cohort is prohibitively costly, genetic association studies take advantage of local correlation structure (or linkage disequilibrium) between single nucleotide polymorphisms (SNPs) by selecting a subset of SNPs to be genotyped (tag SNPs). While many current association studies are performed using commercially available high-throughput genotyping products that define a set of tag SNPs, choosing tag SNPs remains an important problem for both custom follow-up studies as well as designing the high-throughput genotyping products themselves. The most widely used tag SNP selection method optimizes the correlation between SNPs (r(2)). However, tag SNPs chosen based on an r(2) criterion do not necessarily maximize the statistical power of an association study. We propose a study design framework that chooses SNPs to maximize power and efficiently measures the power through empirical simulation. Empirical results based on the HapMap data show that our method gains considerable power over a widely used r(2)-based method, or equivalently reduces the number of tag SNPs required to attain the desired power of a study. Our power-optimized 100k whole genome tag set provides equivalent power to the Affymetrix 500k chip for the CEU population. For the design of custom follow-up studies, our method provides up to twice the power increase using the same number of tag SNPs as r(2)-based methods. Our method is publicly available via web server at http://design.cs.ucla.edu.

Cloning and expression of cryptochrome2 cDNA in the rat

Cryptochromes (CRY) are blue-light photoreceptors that regulate the circadian rhythm in animals and plants. In mammals, two types of CRY are involved in the regulation of circadian rhythm, but rat cryptochromes have not yet been identified. Therefore, we isolated and characterized cry2 cDNA from the rat brain. The cloned rat cry2 cDNA consists of 2,131 nucleotides and has a single open-reading frame that encodes the rat CRY2 of 594 amino acids with start and stop codons. The deduced amino acid sequence of the rat CRY2 was 97% identical with that of mice and 93% with humans, but it showed a relatively low identity of 64% with that of zebrafish. It also exhibited a high homology (about 70%) with CRY1 of mice and humans. A Northern blot analysis showed that rat cry2 was expressed in all of the tissues examined. Rat cry2 was expressed at a relatively higher level in peripheral tissues than in the brain. In situ hybridization in the whole brain indicated that the strong signal of cry2 mRNA is mainly present in the suprachiasmatic nucleus (SCN) region, but very weak in other brain regions. Therefore, present results indicate that rat cry2 may function in circadian photoreception in the rat brain.

Cloning and characterization of cDNAs encoding the GnRH1 and GnRH2 precursors from bullfrog (Rana catesbeiana)

We have isolated the cDNAs encoding the GnRH1 and GnRH2 precursors, respectively, from bullfrog (Rana catesbeiana) brain. The first cDNA consists of 648 bp and contains an open-reading frame of 270 nucleotides, encoding the bullfrog GnRH1 precursor. The second cDNA consists of 1053 bp and contains an open-reading frame of 255 nucleotides, encoding the bullfrog GnRH2 precursor. Both types of bullfrog GnRH precursor have a similar molecular architecture as observed in other GnRH precursors, consisting of a signal peptide, followed by the GnRH decapeptide, a conserved carboxy-terminal amidation and proteolytical processing site, and a GnRH-associated peptide (GAP). In addition, we have identified a third cDNA, containing 24 additional nucleotides in its GAP-coding region. Genomic PCR and sequence analysis confirmed that this cDNA represents an alternative splice variant of the bullfrog GnRH2-precursor pre-mRNA. The bullfrog GnRH1 precursor exhibits 60% and less than 40% amino acid identity to its Xenopus and mammalian counterparts, respectively, whereas the bullfrog GnRH2 precursor displays 50% to 60% amino acid identity to that of its nonmammalian counterparts, but shares only 25% amino acid identity with its mammalian counterparts. Northern blot analysis revealed a single GnRH1-precursor mRNA species of approximately 0.75 kilobases, expressed in bullfrog forebrain, and a single GnRH2-precursor mRNA species of approximately 1.1 kilobases, expressed in bullfrog midbrain/hindbrain. Furthermore, both bullfrog GnRH-precursor mRNAs exhibited a differential spatiotemporal expression pattern. Genomic Southern blot analysis indicated that both bullfrog GnRH genes are present as single copy genes. This is the first report on the molecular cloning of a GnRH2-precursor cDNA from an amphibian species. In addition, we present data showing that alternative splicing is utilized to generate different GnRH2-precursor mRNAs. J. Exp. Zool. 289:190-201, 2001.

Characterization of the Ca2+-binding sites of annexin II tetramer

Annexin II heterotetramer (AIIt) is a multifunctional Ca(2+)-binding protein composed of two 11-kDa subunits and two annexin II subunits. The annexin II subunit contains three type II and two type III Ca(2+)-binding sites which are thought to regulate the interaction of AIIt with anionic phospholipid, F-actin, and heparin. In the present study we utilized site-directed mutagenesis to create AIIt mutants with inactive type III (TM AIIt), type II (CM AIIt), and both type II and III Ca(2+)-binding sites (TCM AIIt). Surprisingly, we found that in the presence of Ca(2+), the TM, CM, and TCM AIIt bound phospholipid and F-actin with similar affinity to the wild type AIIt (WT AIIt). Furthermore, the TCM mutant, and to a lesser extent the TM and CM AIIt displayed dose-dependent Ca(2+)-independent phospholipid aggregation and binding. While the TM and CM AIIt demonstrated Ca(2+)-dependent binding to F-actin, the binding of the TCM AIIt was Ca(2+)-independent. These results suggest that the type II or type III Ca(2+)-binding sites do not directly participate in anionic phospholipid or F-actin binding. We therefore propose that in the absence of Ca(2+), the type II and type III Ca(2+)-binding sites of AIIt stabilize a conformation of AIIt that is unfavorable for binding phospholipid and F-actin. Ca(2+) binding to these sites, or the inactivation of these Ca(2+)-binding sites by site-directed mutagenesis, results in a conformational change that promotes binding to anionic phospholipid and F-actin. Since the TM, CM, and TCM AIIt require Ca(2+) for binding to heparin, we also propose that novel Ca(2+)-binding sites regulate this binding event.

Molecular cloning, distribution and pharmacological characterization of a novel gonadotropin-releasing hormone ([Trp8] GnRH) in frog brain

To date nine structural variants of GnRH have been identified in vertebrates and two additional forms have been isolated from a tunicate. In amphibians only mammalian GnRH ([Arg8] GnRH) and type II GnRH (chicken GnRH II, [His5, Trp7, Tyr8] GnRH) have been identified. In the present study, a full-length cDNA encoding a novel type of GnRH was isolated from pituitary of Rana dybowskii. The GnRH gene encodes a GnRH peptide ([Trp8] GnRH) in which tryptophan is substituted for arginine of mammalian GnRH Northern blot analysis revealed the presence of a single 500 bp transcript for the [Trp8] GnRH precursor in forebrain but its absence in testis, ovary, kidney and liver. Restriction digests of genomic DNA demonstrated a single copy of the gene. The [Trp8] GnRH immunoreactive cells were identified in the preoptic area of the frog brain. Synthetic [Trp8] GnRH was tested for its ability to stimulate inositol phosphate production by COS-1 cells transfected with the cloned Xenopus pituitary GnRH receptor and the cloned human GnRH receptor. [Trp8] GnRH had a potency of about 60% compared with mammalian GnRH ([Arg8] GnRH) for the Xenopus receptor, whereas the potency of [Trp8] GnRH was approximately 5% compared with mammalian GnRH for the human receptor. Both mammalian GnRH and [Trp8] GnRH were 1000-fold less potent than type II GnRH for the Xenopus GnRH receptor. The similar potency of [Arg8] GnRH and the novel [Trp8] GnRH for the Xenopus pituitary receptor indicates that, unlike the human receptor, the Xenopus receptor does not discriminate between these amino acids in position eight thereby allowing substitution of the arginine in the mammalian GnRH.

Regulation of plasmin activity by annexin II tetramer

Annexin II tetramer (AIIt) is a major Ca(2+)-binding protein of the endothelial cell surface which has been shown to stimulate the tissue plasminogen activator (t-PA)-dependent conversion of plasminogen to plasmin. In the present report, we have examined the regulation of plasmin activity by AIIt. The incubation of plasmin with AIIt resulted in a 95% loss in plasmin activity. SDS-PAGE analysis established that AIIt stimulated the autoproteolytic digestion of plasmin heavy and light chains. The kinetics of AIIt-stimulated plasmin autoproteolysis were first-order, suggesting that binding of plasmin to AIIt resulted in the spontaneous autoproteolysis of the bound plasmin. AIIt did not affect the activity of other serine proteases such as t-PA or urokinase-type plasminogen activator. Furthermore, other annexins such as annexin I, II, V, or VI did not stimulate plasmin autoproteolysis. Increasing the concentration of AIIt on the surface of human 293 epithelial cells increased cell-mediated plasmin autoproteolysis. Thus, in addition to stimulating the formation of plasmin, AIIt also promotes plasmin inactivation. These results therefore suggest that AIIt may function to provide the cell surface with a transient pulse of plasmin activity.

Cloning and characterization of cDNA encoding cdc2 kinase, a component of maturation-promoting factor, in Rana dybowskii

In order to understand the mechanism of oocyte maturation in seasonal-breeding wild frogs, we have cloned and sequenced a cDNA encoding Cdc2 kinase, a component of the maturation-promoting factor (MPF) in Rana dybowskii. About 1.2-kb cDNA was isolated by reverse transcription coupled to polymerase chain reaction (RT-PCR) and cDNA library screening. The cloned Rana Cdc2 cDNA encodes a complete open-reading frame with 302 amino acid residues, which deduce a 34-kDa protein. Homology of more than 80% was found between the deduced amino acid sequence of Rana Cdc2 and that of five phylogenetically distant organisms, and 94% identity was found between Rana and Xenopus. More importantly, the Thr14, Tyr15, and Thr161 residues, the phosphorylation sites for the activation of the enzyme, are highly conserved. In vitro-translated Rana Cdc2 cross-reacted with Xenopus p34(cdc2) antibody as shown by Western blot. Northern blot analysis showed that a 1.7-kb transcript was highly expressed in the gonads compared to other tissues, indicating the important role of Cdc2 kinase in gonads as a component of MPF. The cloned Rana Cdc2 cDNA also exhibited histone H1 kinase activity when expressed in CV-1 cells. In the present study, therefore, we have characterized the Rana Cdc2 kinase in amphibian, which will be helpful in understanding the process of oocyte maturation related to the reproduction cycle of wild frogs.

Effects of dopamine and melatonin on the regulation of the PIT-1 isotype, placental growth hormone and lactogen gene expressions in the rat placenta

Rat placenta produces several members of the placental prolactin-growth hormone (PRL-GH), including placental lactogen (PL) and placental prolactin like protein (PLP), during pregnancy. It is important to study placental local regulators that control the expression of PRL-GH genes. We have previously reported that dopamine (DA) can regulate Pit-1 and PL-II gene expressions. In this study we aimed to investigate the local expression of melatonin receptor 1a (Mel1a) and the effects of DA and melatonin on the expressions of PL-Iv, PL-II, PLP-C genes and Pit-1 gene that are involved in the expression of PRL-GH genes in the rat pituitary and placenta. According to the Northern blot analysis, DA receptor 2 (D2) was expressed in the rat placenta. We also report on the local expression of Mel1a in the rat placenta for the first time. Injected DA agonist, bromocriptine (in vivo) decreased PL-Iv, PLP-C and Pit-1 mRNA levels in the rat placenta. The melatonin agonist, chloromelatonin in culture media also decreased the levels of PL-Iv, PL-II and PLP-C mRNA. However, melatonin does not affect the Pit-1 mRNA level. These data suggest that D2 and Mel1a may control the expression of PRL-GH genes in the rat placenta and its response to the extracellular changes of DA and melatonin secreted from the maternal organ. However, Pit-1 may not be involved in the Mel1a induced inhibition of PRL-GH gene expressions in the rat placenta.

Safety of distilled water as an irrigating fluid for transurethral resection of the prostate

BACKGROUND

Irrigating fluid is necessary for transurethral resection of the prostate (TURP). Initially, distilled water was used as irrigating fluid and some advantages and complications were noted. Although other solutions were used to substitute for distilled water, we collected data for changes in electrolytes and hematocrit (Hct) during surgery to evaluate the safety of distilled water as irrigating fluid for TURP with suprapubic trocar cystostomy.

METHODS

Fifty-three patients who underwent TURP using distilled water as irrigating fluid were investigated. TURP was performed with suprapubic trocar cystostomy routinely. Preoperative and postoperative blood samples were collected and analyzed for electrolytes and Hct to study any changes during surgery.

RESULTS

The change in plasma sodium concentration was not statistically significant, but the decreases in blood Hct and plasma potassium concentration were statistically significant. There was no major operative complication and no clinical-evident related postoperative renal impairment.

CONCLUSIONS

Distilled water is a relatively safe solution as an irrigating fluid for TURP under drainage with suprapubic trocar cystostomy, but attention must be paid to the inevitable blood loss during surgery.

Role of annexin II tetramer in plasminogen activation

The enzymatic cascade triggered by activation of plasminogen has been implicated in a variety of normal and pathologic events, such as fibrinolysis, wound healing, tissue remodeling, embryogenesis, and the invasion and spread of transformed tumor cells. Recent data established that the Ca(2+)- and phospholipid-binding protein, annexin II heterotetramer (AIIt) binds tissue-type plasminogen activator (tPA), plasminogen, and plasmin, and dramatically stimulates the tPA-dependent conversion of plasminogen to plasmin in vitro. Interestingly, the binding of plasmin to AIIt can inhibit the activity of the enzyme, suggesting that plasmin bound to the cell surface is regulated by AIIt. The existing experimental evidence suggests that AIIt is the key physiological receptor for plasminogen on the extracellular surface of endothelial cells.

The p11 subunit of the annexin II tetramer plays a key role in the stimulation of t-PA-dependent plasminogen activation

Annexin II tetramer (AIIt) is an important endothelial cell surface protein receptor for plasminogen and t-PA. AIIt, a heterotetramer, is composed of two p36 subunits (called annexin II) and two p11 subunits. In this report, we have compared the ability of the isolated p36 and p11 subunits to stimulate t-PA-dependent [Glu]plasminogen activation. The fluid-phase recombinant p11 subunit stimulated the rate of t-PA-dependent activation of [Glu]plasminogen about 46-fold compared to an approximate stimulation of 2-fold by the recombinant p36 subunit and 77-fold by recombinant AIIt. The stimulation of t-PA-dependent activation of [Glu]plasminogen by the p11 subunit was Ca2+-independent and inhibited by epsilon-aminocaproic acid. [Glu]Plasminogen bound to a p11 subunit affinity column and could be eluted with epsilon-aminocaproic acid. Both AIIt and the p11 subunit protected t-PA and plasmin from inactivation by PAI-1 and alpha2-antiplasmin, respectively. A peptide to the C terminus of the p11 subunit (85-Y-F-V-V-H-M-K-Q-K-G-K-K-96) inhibited the p11-dependent stimulation of t-PA-dependent plasminogen activation. In addition, a deletion mutant of the p11 subunit, missing the last two C-terminal lysine residues, retained only about 15% of the activity of the wild-type p11 subunit. Similarly, a mutant AIIt composed of the wild-type p36 subunit and the p11 subunit deletion mutant possessed about 12% of the wild-type activity. These results, therefore, suggest that the C-terminal lysine residues of the p11 subunit bind plasminogen and participate in the stimulation of t-PA-dependent activation of plasminogen by AIIt.

Testicular cycles in three species of Korean frogs: Rana nigromaculata, Rana rugosa, and Rana dybowskii

Seasonal changes in testicular structure and function in three species of Korean frogs (Rana nigromaculata, R. rugosa, and R. dybowskii) having different breeding seasons and habitats were examined throughout the year. R. nigromaculata live in rice fields and breed in early May. Their gonadosomatic index (GSI) and testis weight decreased slightly from May until July, but increased markedly from August to high levels through December. The diameter (cross-sectional area) of seminiferous tubules changed little from January until August, increased sharply from September through October, and decreased thereafter. In seminiferous tubules, the number of primary spermatogonia (I SPG) was low from January-March, increased from April to maximum levels by May-June, and decreased subsequently. The number of spermatids (SPT) was highest from November to March, decreased to nondetectable levels in May, and increased markedly from September to November. Spermiation was most active during March and April. R. rugosa, which live in streams and breed during May-June, exhibited no changes in GSI, testis weight, or seminiferous tubule size throughout the year. The number of I SPG was high during May-August and that of secondary spermatogonia (II SPG) was highest in August. The number of SPT increased to high levels in November-December. Active spermiation occurred from January to April in this frog. In R. dybowskii, which live in the mountains and breed from late February to early March, the number of I SPG gradually increased from April through August; however, essentially no other spermatogenic cells were observed from January to July. A marked increase in early spermatogenic cells appeared during August-September and was followed by an increase in SPT from November to December. From December to March the number of spermatozoa increased and spermiation occurred. In general, testicular testosterone levels were high in the winter and low in summer in all three species, and positively correlated with the number of interstitial cells and the size of their nucleus.

Blood sampling site-dependent plasma concentrations and hepatotoxic parameters in serum after intraperitoneal administration of acetaminophen to rats

Blood sampling site-dependent (the dorsal aorta, the jugular vein, and the retro-orbital sinus) plasma concentrations of acetaminophen and its glucuronide and sulfate conjugates, and acetaminophen-induced hepatotoxic parameters (such as ALT and SDH activity) in serum were evaluated after intraperitoneal administration of acetaminophen, 500 mg/kg body weight, to rats. The plasma concentrations and the resultant AUC0-12 h of acetaminophen, acetaminophen-glucuronide, and acetaminophen-sulfate were significantly higher when blood samples were collected from the retro-orbital sinus than those from the jugular vein. The serum ALT activity at 3 and 24 h after administration of acetaminophen were significantly higher when the blood samples were collected from the retro-orbital sinus than those from the dorsal aorta.

Effects of dopamine and estrogen on the regulation of Pit-1 alpha, Pit-1 beta, and PL-II gene expression in the rat placenta

Pituitary-specific transcription factor Pit-1 regulates growth hormone and prolactin gene expression in the pituitary. Recently, Pit-1 was shown to be locally synthesized in the rat placenta and is involved in the regulation of rat placental lactogen (PL) gene expression. Pit-1 has three different splicing variants. They are well known as being biologically active. In the present study, we found that Pit-1 beta is also synthesized in the rat placenta and we tried to examine the effects of dopamine and estrogen on the regulation of Pit-1 alpha, beta and PL-II genes expression using the reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot hybridization. A dopamine receptor agonist, bromocriptine, significantly decreased placental Pit-1 alpha, beta, and PL-II mRNA levels. To examine the effect of estrogen on the gene expression of Pit-1 beta, pregnant female rats were ovariectomized (OVX) and injected daily with 17 beta-estradiol. OVX markedly lowered the amount of Pit-1 beta mRNA. Estrogen injection recovered the OVX-induced inhibition of Pit-1 beta mRNA level. Finally, we investigated the site-specific transcription of Pit-1 alpha and beta mRNA in the labyrinth zone and junctional zone of the placental in 15 and 20 days of gestation. The main site of Pit-1 alpha and beta synthesis was shifted from the junctional zone to the labyrinth zone from 15 to 20 days of gestation. Together, these data presume that Pit-1 beta may play a more important role in the placenta than in the pituitary and that Pit-1 may be involved in the regulation of the PL and prolactin-like peptide by estrogen and dopamine in the rat placenta.

The role of annexin II tetramer in the activation of plasminogen

Annexin II tetramer (AIIt) is a major Ca2+-binding protein of endothelial cells which has been shown to exist on both the intracellular and extracellular surfaces of the plasma membrane. In this report, we demonstrate that AIIt stimulates the activation of plasminogen by facilitating the tissue plasminogen activator (t-PA)-dependent conversion of plasminogen to plasmin. Fluid-phase AIIt stimulated the rate of activation of [Glu]plasminogen about 341-fold compared with an approximate 6-fold stimulation by annexin II. AIIt bound to [Glu]plasminogen(S741C-fluorescein) with a Kd of 1. 26 +/- 0.04 microM (mean +/- S.D., n = 3) and this interaction resulted in a large conformational change in [Glu]plasminogen. Kinetic analysis established that AIIt produces a large increase of about 190-fold in the kcat, app and a small increase in the Km,app which resulted in a 90-fold increase in the catalytic efficiency (kcat/Km) of t-PA for [Glu]plasminogen. AIIt also stimulated the t-PA-dependent activation of [Lys]plasminogen about 28-fold. Furthermore, other annexins such as annexin I, V, or VI did not produce comparable activation of t-PA-dependent conversion of [Glu]plasminogen to plasmin. The stimulation of the activation of [Glu]plasminogen by AIIt was Ca2+-independent and inhibited by epsilon-aminocaproic acid. AIIt bound to human 293 cells potentiated t-PA-dependent plasminogen activation. AIIt that was bound to phospholipid vesicles or heparin also stimulated the activation of [Glu]plasminogen 5- or 11-fold, respectively. Furthermore, immunofluorescence labeling of nonpermeabilized HUVEC revealed a punctated distribution of AIIt subunits on the cell surface. These results therefore identify AIIt as a potent in vitro activator of plasminogen.

Annexin II tetramer inhibits plasmin-dependent fibrinolysis

In this paper, we have characterized the regulation of plasmin activity by annexin II tetramer (AIIt). Plasmin activity was measured by a fibrin lysis assay in which a fibrin polymer was produced from purified components and the extent of polymer lysis was determined by following changes in turbidity. Extrinsic lysis of the fibrin polymer, initiated by addition of tissue plasminogen activator (t-PA), was totally blocked if AIIt was present during fibrin polymer formation. Furthermore, fibrin polymer formed in the presence of AIIt was resistant to extrinsic lysis initiated by addition of plasmin. AIIt bound to fibrin polymer under conditions in which polymer lysis was inhibited. Plasmin-dependent extrinsic lysis of the fibrin polymer was also blocked if AIIt was present in the incubation medium, and under these conditions the amidolytic activity of plasmin, measured with an artificial substrate, was inhibited about 5-fold. In contrast, in the absence of fibrin, and at an AIIt/plasmin molar ratio of 526, the amidolytic activity of plasmin was inhibited by only 22.3% +/- 7.4% (mean +/- SD, n = 5) by AIIt. Plasmin-dependent fibrinolysis was only slightly inhibited if fibrin polymer was formed in the presence of annexins I, II, V, or VI. These results identify AIIt as an in vitro regulator of plasmin activity.

Dicistronic tagging of genes active in embryonic stem cells of mice

A gene-trap vector, pWH14, has been developed to tag genes expressed in embryonic stem (ES) cells of the mouse. The approach relies on the ability of the endogenous promoter to drive promoterless neo-IRES-lacZ construct producing a dicistronic mRNA consisting of the neomycin-resistance (neo) gene and the beta-galactosidase gene sequence. The neo gene produces a chimeric protein with the truncated product of the tagged gene and serves as a selectable marker for an insertion into an expressed gene. The internal ribosome entry site (IRES) sequence from murine encephalomyocarditis virus allows the translation of the second cistron, lacZ, to produce beta-galactosidase that can be used as a reporter for the expression of the tagged gene. The pWH14 vector was introduced into ES cells by electroporation, and the cells were selected for G418-resistance. About 50% of the G418-resistant colonies were stained positive for the beta-galactosidase activity. Southern analysis showed that each clone had one or more vector sequences integrated. Northern blot analysis of the clones positive for beta-galactosidase indicated that the fused RNAs containing the neo and the beta-gal genes were derived from the endogenous promoters of the tagged genes. Seven clones were chosen and injected into blastocysts, and chimeras were obtained. Two of the gene-trap insertions (wh14.1 and wh14.3) were transmitted through germ-line. In these two lines, the pattern of lacZ expression was restricted to early stages of embryos. This gene-trap vector may provide a means for tagging and studying the active genes in vivo in early embryogenesis.

Characterization of human recombinant annexin II tetramer purified from bacteria: role of N-terminal acetylation

Annexin II tetramer (AIIt) is a Ca2+-dependent, phosphatidylserine-binding, and F-actin-bundling phosphoprotein which is localized to both the extracellular and cytoplasmic surfaces of the plasma membrane. The tetramer is composed of two p36 heavy chains and two p11 light chains. We have produced prokaryotic cDNA expression constructs for both p36 and p11. Both proteins were expressed in large amounts in Escherichia coli upon induction with IPTG. Electrospray ionization mass spectrometry and amino acid sequence analysis of purified recombinant p36 (rp36) and recombinant p11 (rp11) suggested that the recombinant proteins were identical to their native counterparts except for the lack of N-terminal acetylation of rp36. Furthermore, the non-acetylated rp36 bound rp11 and formed AIIt. The circular dichroism spectra and urea denaturation profiles of acetylated AIIt and non-acetylated rAIIt were identical. In addition, both the acetylated AIIt and non-acetylated rAIIt were similar in their Ca2+ dependence and concentration dependence of phospholipid liposome aggregation, chromaffin granule aggregation, and F-actin bundling. These results suggest that N-terminal acetylation of p36 is not in fact necessary for binding of the protein to p11 and that N-terminal acetylation does not affect the conformational stability of AIIt or the in vitro activities of AIIt. The availability of large amounts of rAIIt will facilitate further characterization of the structure-function relationships of the protein.

Differential effects of gonadotropin and orthovanadate on oocyte maturation, ovulation, and prostaglandin synthesis by Rana ovarian follicles in vitro

Effects of gonadotropin and sodium orthovanadate on oocyte maturation, ovulation, prostaglandin, and progesterone synthesis were examined during in vitro culture of Rana ovarian follicles obtained from hibernating animals. Frog pituitary homogenates (FPH, 0.05 gland/ml) effectively induced oocyte maturation (germinal vesicle breakdown, GVBD) and ovulation (> 90%) in ovarian follicles obtained in mid-hibernation (mid-December through late January). In contrast, orthovanadate induced a limited amount (< 45%) of ovulation of some oocytes without concomitant induction of maturation during mid-hibernation. In late hibernation (February to early March), considerable spontaneous maturation and ovulation occurred in cultured ovarian follicles. During this period both FPH (0.0005-0.05 gland/ml) or orthovanadate (0.01-1 mM) treatment markedly increased the incidence of ovulation and accelerated the onset of ovulation in a dose dependent manner. When examined after 12 h of culture, few (< 5%) oocytes ovulated in response to orthovanadate had undergone GVBD whereas most (> 90%) of those ovulated in response to FPH had matured. However, the majority of oocytes ovulated (72%) within 6 h of exposure to FPH had intact GVs, indicating that GVBD is also not a prerequisite for ovulation induction in response to FPH. Orthovanadate stimulated PGF2 alpha in a dose dependent manner but failed to stimulate progesterone production whereas FPH stimulated secretion of both PGF2 alpha and progesterone. The amount and time course of PGF2 alpha secretion in response to orthovanadate were similar to results produced with FPH stimulation. Treatment of PGF2 alpha to follicles obtained in late hibernation also accelerated the ovulation of the oocytes. Taken together, the data suggest that orthovanadate enhanced ovulation of immature oocytes was mediated via enhanced PGF2 alpha production and that oocyte maturation is not essential or prerequisite for in vitro oocyte ovulation in Rana.

The factors related to recurrence after transcatheter arterial embolization for the treatment of hemoptysis

OBJECTIVES

Massive hemoptysis is a major clinical problem associated with high morbidity and mortality. Transcatheter arterial embolization is widely used for the treatment of massive hemoptysis, but it was reported that the recurrence rate after embolization is 12-54% in the previous studies. We evaluated the therapeutic effect of transcatheter arterial embolization for the treatment of massive hemoptysis and the factors related to recurrence.

METHODS

We reviewed 51 patients (M:F = 36:15) of transcatheter arterial embolization for the treatment of massive hemoptysis from Jan 1988 to Dec 1994, retrospectively.

RESULTS

After arterial embolization, immediate successful control (< 1 wk) of massive hempotysis was achieved in 48 of 51 patients (94.1%) and recurrence of hemoptysis was observed in 17 of 51 patients (33.3%) during the follow-up period. The patients with non-bronchial artery hemoptysis and multiple artery bleeding had increased tendency of recurrence (77.7%). On the previous history of hemoptysis, the patients with massive hemoptysis (> 400 ml/24hr) or frequent history of hemoptysis had increased tendency of recurrence (87.5%, 72.7%).

CONCLUSION

Transcatheter arterial embolization is a useful and safe procedure for immediate control in massive hemoptysis. However, the patients with this procedure had a potentiality for recurrence. We suggest that close follow-up and caution will be needed in the patients with multiple artery bleeding or with large amounts of hemoptysis or with previous episodes more than 3 times.

Structure-function relations of smooth muscle calponin. The critical role of serine 175

Calponin has been implicated in the regulation of smooth muscle contraction through its interaction with F-actin and inhibition of the actin-activated MgATPase activity of phosphorylated myosin. Both properties are lost following phosphorylation (primarily at serine 175) by protein kinase C or calmodulin-dependent protein kinase II. To evaluate further the functional importance of serine 175, wild-type calponin and three site-specific mutants (S175A, S175D, and S175T) were expressed in Escherichia coli and compared with calponin purified from chicken gizzard smooth muscle in terms of actin binding, actomyosin MgATPase inhibition, and phosphorylation by protein kinase C and calmodulin-dependent protein kinase II. The affinities of skeletal muscle F-actin for wild-type and S175T calponins were similar to that for the tissue-purified protein (Kd = 0.8, 1.3, and 1.0 microM, respectively), whereas the affinities for S175A and S175D calponins were much lower (Kd = 26.8 and 44.2 microM, respectively). Tissue-purified, wild-type, and S175T calponins displayed comparable inhibition of the smooth muscle actin-activated myosin MgATPase, whereas S175A and S175D calponins were much less effective. Phosphorylation confirmed serine 175 as the principal site of phosphorylation by both kinases. These results indicate that the hydroxyl side chain at position 175 of calponin plays a critical role in the binding of calponin to actin and inhibition of the cross-bridge cycling rate.

Changes in mRNA levels of a pituitary-specific trans-acting factor, Pit-1, and prolactin during the rat estrous cycle

The present study examined the changes in mRNA levels of a pituitary-specific trans-acting factor, Pit-1, and prolactin during the rat estrous cycle. Total cytoplasmic RNA was analyzed by Northern blot and slot-blot hybridization to examine the prolactin mRNA level. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to examine the Pit-1 mRNA level. Proestrous and estrous prolactin mRNA levels were significantly higher than the metestrous and diestrous levels, whereas Pit-1 mRNA levels of the estrous and metestrous stages were about two- to threefold higher than those of the proestrous and diestrous stages. Proestrous Pit-1 mRNA levels increased gradually from 10.00 h to 20.00 h, while prolactin mRNA levels slightly decreased until 14.00 h but increased later until 20.00 h. During the rat estrous cycle, especially in the afternoon of the proestrous day, changes of prolactin mRNA levels seem to follow a prior increase of Pit-1 mRNA. Therefore, Pit-1 may be partly involved in the regulation of prolactin gene expression according to the rat estrous cycle. Estradiol administration to ovariectomized rats significantly increased both the mRNA levels of prolactin and Pit-1, which suggests that the gene expression of Pit-1 is regulated by estrogen through indirect extracellular pathways.

Will epidural with light general anesthesia increase the incidence of awareness with recall or dream postoperatively

BACKGROUND

The incidence of awareness with recall during general combined with epidural anesthesia has not been previously reported. The purpose of this study was to quantify the incidence.

MATERIALS & METHODS

One hundred patients were divided into two groups. Group 1 (N = 50) received general anesthesia (GA), Group 2 (N = 50) received GA and epidural anesthesia (EA) intraoperatively. No premedication was given. These patients were induced with thiopentol (5 mg/kg) or propofol (2.0 mg/kg) and anectine (1.2 mg/kg) for smooth tracheal intubation and maintained with N2O:O2 = 1.5:1.5, and isoflurane and muscle relaxant of either pavulon or atracurium. No sedatives was given. Before anesthesia, we introduced an epidural catheter into the group 2 patients. After induction, headphones with soft music were given to the patients, in both groups, throughout the operation. 20-36 hours after operation or when the patients were fully awake, we asked the patients if they had heard anything or dreamed intraoperatively.

RESULTS

We found that not one of the one hundred patients heard anything or dreamed intraoperatively.

Observation of coagulation change during induced hypotensive anesthesia and autologous plasma transfusion

Coagulation change was studied in 16 adult female patients undergoing radical hysterectomy with BPLND surgery. None had preoperative alterations in coagulation or liver function and was receiving anticoagulant or antiplatelet medication. Sixteen ASA class I-II were divided into 2 groups randomly with eight patients in each group. One group accepted autologous plasma transfusion near the end of surgery, the other group did not. Autologous plasma was retrieved by plasma saver post induction of anesthesia. Every patient received induced hypotensive anesthesia during the operation. Whole blood coagulation status was quantitated by using thromboelastography (TEG). Blood samples for TEG were obtained before induction of anesthesia, after closure of peritoneum, and 2 hours post autologous plasma transfusion or 2 hours post peritoneum closure. Most parameters measured by TEG showed improved coagulation status in autologous plasma transfusion group. We concluded that coagulation change was minimal during induced hypotension, and improved coagulation was obtained 2 hours post autologous plasma transfusion during radical hysterectomy with BPLND surgery.

Calponin phosphorylation in vitro and in intact muscle

Calponin, a thin-filament-associated protein implicated in the regulation of smooth-muscle contraction, is phosphorylated in vitro by protein kinase C and Ca2+/calmodulin-dependent protein kinase II [Winder and Walsh (1990) J. Biol. Chem. 265, 10148-10155] and dephosphorylated by a type 2A protein phosphatase [Winder, Pato and Walsh (1992) Biochem. J. 286, 197-203]. Unphosphorylated calponin binds to actin and inhibits the actin-activated myosin MgATPase; these properties are lost on phosphorylation. Although both serine and threonine residues in calponin are phosphorylated, the major site of phosphorylation by either kinase is Ser-175. Calponin also undergoes phosphorylation when bound to actin in synthetic thin filaments, in a reconstituted actomyosin system, in washed myofibrils and in tissue extracts; this results in dissociation of calponin from actin. Tryptic phosphopeptide mapping indicates that the same sites are phosphorylated in the bound as in the isolated protein. Toad stomach calponin exists in at least three isoforms which differ in charge but exhibit the same molecular mass on SDS/PAGE. In a toad stomach extract, all three isoforms are phosphorylated by protein kinase C or Ca2+/calmodulin-dependent protein kinase II as shown by two-dimensional gel electrophoresis (non-equilibrium pH-gradient gel electrophoresis and SDS/PAGE). Calponin phosphorylation also occurs in intact toad stomach smooth-muscle strips metabolically labelled with 32Pi and stimulated to contract with carbachol. These results support the hypothesis that calponin may be regulated in vivo by phosphorylation-dephosphorylation.

The influence of position and PEEP on arterial blood gas during operation

From December, 1990 to December, 1991, we studied the influence of PEEP and positional change to arterial blood gas in 60 ASA class II or III, aged 20 to 65 years, non-obese patients. The patients were assigned randomly into six groups. Group 1: head down position without PEEP. Group 2: head down position with PEEP 5 cmH2O. Group 3: lithotomy position without PEEP. Group 4: lithotomy position with PEEP 5 cmH2O. Group 5: supine position without PEEP. Group 6: supine position with PEEP 5 cmH2O. Blood gas analysis were performed at 5, 15, 30, 60, 120, and 180 minutes after positional change in group 1-4 and after anesthesia in group 5 and 6. The ventilator settings were: tidal volume -10 ml x 25 x (height in meters)2, rate 8/min. The results of significant difference inter-grouply were: PaO2 at 15 minutes; PaCO2 at 5 minutes; pH at 60, 120, and 180 minutes; base excess (BE) at 120 and 180 minutes. As the time progressed, PaO2 decreased in group 1, 2, and 3; PaCO2 decreased in group 3 and 5; pH decreased in group 3; BE decreased in all groups. PaCO2 were between 30-40 mmHg and no hypocarbia produced in all groups. In conclusion, ventilation of the non-obese patient based on 10 ml x 25 x (height in meters)2 x 8/min produce normocarbia and PaO2 more than 80 mmHg with 50% oxygen. No significant difference of PaO2 were found whether there were position change or PEEP 5 cmH2O.

Construction of a bifunctional mRNA in the mouse by using the internal ribosomal entry site of the encephalomyocarditis virus

Picornaviral mRNAs have been shown to possess special structures in their 5' nontranslated regions (5'NTRs) that provide sites for internal binding of ribosomes and thus direct cap-independent translation. The translational cis-acting elements for ribosomal internal entry into the 5'NTR of encephalomyocarditis virus (EMCV), a member of family Picornaviridae, have been named the internal ribosomal entry site (IRES). All of the published experiments regarding the IRES function of the picornavirus 5'NTR, however, were performed with cell extracts in vitro or with tissue culture cells in transient assay systems. In this study, we examined the IRES function of the EMCV 5'NTR in chimeric mouse embryos and demonstrated that this element does in fact work stably in mouse embryos as well as in embryonic stem (ES) cells. By using a dicistronic vector, pWH8, consisting of a promoter-driven neomycin resistance gene (neo) followed by the EMCV 5'NTR-lacZ sequence, we showed that more than half of the ES cells made G418 resistant by the vector stained positive for beta-galactosidase (beta-gal). On Northern (RNA) blots, all of the clones analyzed revealed a transcript of the expected size containing both the beta-gal and the neo cistrons. These results indicate that dicistronic mRNAs are produced from the stably integrated vector in those ES clones and that both of the cistrons are translated to produce functional proteins. The chimeric embryos derived from these ES clones also stained positive for beta-gal, suggesting that the bifunctional mRNAs are active in the embryos. This dicistronic vector system provides a novel tool by which to obtain temporally and spatially coordinated expression of two different genes driven by a single promoter in a single cell in mice.

Comparison of antiemetic effect among ephedrine, droperidol and metoclopramide in pediatric inguinal hernioplasty

Prevention and treatment of postoperative nausea and vomiting with ephedrine, droperidol and metoclopramide have been reported to be effective. To further investigate their efficacy, 100 pediatric patients scheduled to undergo inguinal hernioplasty on ambulatory basis were divided into five groups, namely, group 1: normal saline (iv) control; group 2: ephedrine 0.5 mg/kg, (im); group 3: droperidol 50 micrograms/kg. (iv); group 4: ephedrine 1 mg/kg. (im); group 5: metoclopramide 0.15 mg/kg. (iv). At the end of surgery, each patient received the drug treatment according to the specified group to which he was randomly assigned. The occurrence of postoperative nausea and vomiting was recorded in the recovery room and inquired at home by telephone within 24 h following surgery by a blinded observer. The authors found that there were no significant differences between the control group and ephedrine groups with whichever dose that was used in the prevention of postoperative nausea and vomiting. Droperidol and metoclopramide were effective in dealing with problem in comparison with control group (p less than 0.05). However, metoclopramide was more suitable than droperidol for pediatric outpatient based on duration of somnolence, return of orientation, and time of discharge.

Protein modification by phosphorylation during the process of nuclear membrane dissolution in puromycin-treated mouse oocytes

The present study was undertaken to elucidate the mechanism of nuclear membrane dissolution (NMD) in puromycin-treated mouse oocytes. Treatment of germinal vesicle breakdown (GVBD) oocytes with puromycin (50 micrograms/ml) induced chromosome decondensation with formation of a polar body; these are designated nuclear membrane (NM) oocytes. After withdrawal of puromycin, NM oocytes underwent NMD (approximately 70%) during a 12-h culture period. Either dibutyryl cyclic AMP (dbcAMP, 25-100 micrograms/ml) or isobutylmethylxanthine (IBMX, 0.1-1.0 mM) inhibited the process of NMD in a dose-dependent manner, suggesting the involvement of cAMP in the process of NMD. To determine which protein(s) participated in the transition from interphase to metaphase II during NMD, NM oocytes were labeled with [35S]methionine, and one- and two-dimensional gel electrophoresis were performed. Although the synthesis of stage-specific proteins during NMD was not found, two specific proteins of Mr 27,000 and 46,000, which were synthesized at interphase following removal of puromycin, were modified during NMD. Phosphatase treatment and 32PO4-labeling experiments indicated that phosphorylation was responsible for these modifications, which were inhibited by either dbcAMP or IBMX. Therefore, it appears that phosphorylation of specific proteins may play an important role in the transition from interphase to metaphase II.

Regulation of laminin gene expression in the expansion of mouse blastocysts

This study aims to elucidate gene expression of laminin and its role in expansion of the blastocyst during mouse early embryo-genesis. The gene expression of laminin, in particular the B1 subunit and the synthesis of laminin polypeptides, was examined during the expansion of blastocyst by a RNA-blot hybridization with 32P-labeled laminin B1 cDNA and immunoprecipitation followed by a SDS-PAGE, respectively. Laminin B1 transcript was actively expressed in the blastocyst stage of embryos. The gene expression of laminin B1 and the synthesis of laminin protein were also increased when blastocyst was expanded. Treatments of cAMP analogue, isobutylmethylxanthine, forskolin, and cholera toxin, which are known to stimulate the blastocyst expansion, increased laminin B1 transcript levels and synthesis of laminin polypeptides. Treatment with retinoic acid, a known regulator of laminin gene expression, not only increased the gene expression of laminin but stimulated the blastocoel expansion without a significant increase in intracellular cAMP levels. These results indicate that laminin gene expression may play an important role in the process of blastocyst expansion in the mouse preimplantation embryos.