[Soft tissue reconstruction strategy for sacral tumor resection]

Objective: To investigate the clinical strategy and effect of soft tissue reconstruction after sacral tumor resection in different planes. Methods: The data of 27 consecutive patients who underwent primary or secondary sacral tumor resection and soft tissue reconstruction from June 2012 to June 2021 at Dongnan Hospital of Xiamen University (the 909th Hospital) were retrospectively analyzed. There were 11 males and 16 females, aged (M(IQR)) (46.2±23.6) years (range: 16 to 72 years). Sacrospinous muscle, gluteus maximus and vertical rectus abdominis muscle flap were selected for soft tissue reconstruction according to the tumor site and the size of tissue defect. the postoperative follow-up was performed. The operative methods, intraoperative conditions, complications and disease outcomes were summarized. Results: Among the 27 patients with sacral tumor, the tumor plane was located in S₁ in 8 cases, S₂ in 5 cases and S₃ or below in 14 cases. There were 12 patients with tumor volume≤400 cm³ and 15 patients with tumor volume>400 cm³. Operation time was 100(90) minutes (range: 70 to 610 minutes), intraoperative blood loss was 800(1 600) ml (range: 400 to 6 500 ml). Soft tissue reconstruction was performed by transabdominal rectus abdominis transfer repair in 2 cases, extraperitoneal rectus abdominis transfer repair in 1 case, gluteus maximus transfer repair in 5 cases, gluteus maximus advancement repair in 13 cases, and sacrospinous muscle transfer repair in 6 cases. Postoperative complications occurred in 6 cases, including 1 case of incision infection, 4 cases of skin border necrosis, and 1 case of delayed infection due to fracture of internal fixator 3 years after operation, all of them were cured. The follow-up time was (35±21) months. Among the patients, 6 patients had recurrence, 2 patients with Ewing sarcoma died of lung metastasis 1 year after operation, 4 patients with metastatic cancer died of primary disease, and the remaining patients survived without disease. Conclusion: Choosing different soft tissue reconstruction strategies according to sacral tumor location and tissue defect size can effectively fill the dead space after sacral tumor resection, reduce postoperative complications and improve the prognosis of patients.

[Expression of miR-212 and miR-132 in serum of patients with primary liver cancer and their targeted regulation of GP73]

Objective: To investigate the expression of miR-212 and miR-132 in the serum of patients with primary liver cancer and their targeted regulation of GP73. Methods: The patients with liver cancer, chronic hepatitis B, or liver cirrhosis who were hospitalized in Taizhou People's Hospital from January 2015 to December 2016 were enrolled, and healthy volunteers were also enrolled as controls. Quantitative real-time PCR was used to measure the serum levels of miR-212 and miR-132, and the association between the expression of serum miR-212 and miR-132 and the clinicopathological features of patients with liver cancer was analyzed. A Spearman's rank correlation analysis was used to analyze the correlation between serum miR-212/miR-132 and GP73. Western blot was used to measure the protein expression of GP73, and MTT assay was used to measure the survival rate of cells. The Levene's homogeneity of variance test was used for data analysis. The independent samples t-test was used for comparison of means between two samples, and ANOVA was used for comparison of means between multiple samples. Results: A total of 90 patients with liver cancer, 60 with chronic hepatitis B, 68 with liver cirrhosis, and 100 healthy volunteers were enrolled. The relative expression levels of miR-212 and miR-132 in serum were 0.046 6 ± 0.024 7 and 0.005 9 ± 0.003 0 in the patients with liver cancer, 0.979 7 ± 0.259 5 and 1.001 8 ± 0.249 9 in the healthy volunteers, 0.588 2 ± 0.216 5 and 0.345 7 ± 0.233 8 in the patients with hepatitis, and 0.313 8 ± 0.153 3 and 0.080 1 ± 0.042 66 in the patients with liver cirrhosis. Compared with the normal controls, all patients had significant reductions in the expression of serum miR-212 (t = 10.26, 20.86, and 35.80, all P < 0.01) and miR-132 (t = 16.55, 36.09, and 39.85, all P < 0.01). In the patients with liver cancer, the relative expression of miR-212 and miR-132 was negatively correlated with alpha-fetoprotein (miR-212: t = -4.46, P < 0.01; miR-132: t = -4.83, P < 0.01), TNM stage (miR-212: t = 6.569, P < 0.01; miR-132: t = 7.31, P < 0.01), degree of tumor differentiation (miR-212: t = 5.268, P < 0.01; miR-132: t = 5.914, P < 0.01), and presence of portal vein tumor thrombus (miR-212: t = 5.16, P < 0.01; miR-132: t = 3.681, P < 0.01), while it was not correlated with tumor size (miR-212: t = 0.687, P > 0.05; miR-132: t = 0.887, P > 0.05). In addition, serum miR-212 and miR-132 were negatively correlated with GP73 in the patients with liver cancer (miR-212: r(s) = -0.709, P < 0.01; miR-132: r(s) = -0.877, P < 0.01). Overexpression of miR-212 or miR-132 in HepG2 cells significantly inhibited the activity and expression of 3'-UTR, and interference of miR-212 or miR-132 significantly increased the activity and expression of 3'-UTR in GP73. Overexpression of GP73 reversed the reduction in survival rate of hepatoma cells induced by the overexpression of miR-212 or miR-132. Conclusion: Patients with liver cancer have a significant reduction in the expression of miR-212 and miR-132 in serum, which is closely associated with the development, progression, and metastasis of liver cancer, and miR-212 and miR-132 in hepatoma cells inhibit the growth of liver cancer by targeted regulation of GP73 expression.

Motivators and deterrents to blood donation among Black South Africans: a qualitative analysis of focus group data

BACKGROUND AND OBJECTIVES

South Africa has a markedly skewed representation where the majority of blood (62%) is presently collected from an ethnically White minority. This study seeks to identify culturally specific factors affecting motivation of donors in South Africa.

MATERIALS AND METHODS

We performed a qualitative study to evaluate motivators and deterrents to blood donation among Black South Africans. A total of 13 focus groups, comprising a total of 97 Black South Africans, stratified by age and geographic location were conducted. Transcripts of the interviews were analysed using a coding framework by Bednall & Bove.

RESULTS

Participants made 463 unique comments about motivators focusing primarily on promotional communications (28%), incentives (20%) and prosocial motivation (16%). Participants made 376 comments about deterrents which focused primarily on fear (41%), negative attitudes (14%) and lack of knowledge (10%).

CONCLUSION

Although prosocial motivation (altruism) was the most frequently mentioned individual motivator, promotional communication elicited more overall comments by participants. As reported by many authors, fear and lack of awareness were strong deterrents, but scepticism engendered by perceived racial discrimination in blood collection were unique to the South African environment.

Aberrant activation of liver X receptors impairs pancreatic beta cell function through upregulation of sterol regulatory element-binding protein 1c in mouse islets and rodent cell lines

AIMS/HYPOTHESIS

Liver X receptors (LXR) are important transcriptional regulators of lipid and glucose metabolism. Our previous report demonstrated that LXR activation inhibited pancreatic beta cell proliferation through cell cycle arrest. Here we explore the role of LXR activation in beta cell insulin secretion and the underlying mechanism that might be involved.

METHODS

Mouse pancreatic islets or insulin-secreting MIN6 cells were exposed to the LXR agonist, T0901317, and insulin secretion, glucose and fatty acid oxidation, and lipogenic gene expression were assessed. The unsaturated fatty acid eicosapentaenoic acid and the dominant negative sterol regulatory element binding protein 1c (SREBP1c) were used to inhibit endogenous SREBP1c and evaluate the involvement of SREBP1c in beta cell dysfunction induced by LXR activation.

RESULTS

Treatment with the LXR agonist decreased beta cell glucose sensitivity and impaired glucose-stimulated insulin secretion in vivo and in vitro. This was accompanied by derangements of beta cell glucose oxygen consumption, glucose oxidation, ATP production and intracellular voltage-gated calcium channel flux. LXR activation also regulated the expression of lipid metabolism-related genes such as Fas, Acc (also known as Acaca) and Cpt1a, and led to intracellular lipid accumulation. Further studies revealed that inhibition of SREBP1c abolished LXR activation-induced lipid accumulation and improved beta cell glucose metabolism, ATP production and insulin secretion.

CONCLUSIONS/INTERPRETATION

Our data reveal that aberrant activation of LXR reproduced the phenomenon of beta cell dysfunction in the development of type 2 diabetes in vitro and in vivo. Upregulation of SREBP1c production and the lipotoxicity mediated by it played a central role in this process.

A minimally invasive anterior approach to reduction and screw fixation of coronoid fractures

We investigated a minimally invasive anterior approach to reduce and fix coronoid fractures with a screw in eight consecutive patients and evaluated seven patients at a minimum of 1 year (mean, 78 weeks; range, 61-89 weeks). It was only possible to repair seven of eight coronoid fractures. The average time to radiographic healing was 12 weeks and all healed without the screw loosening, migration or breakage. Endoscopy permitted an excellent view of coronoid fractures, allowing anatomic fixation, and as it avoided extensive soft tissue dissection, this method preserved soft tissue attachments of small coronoid fragments. This method was safe and minimally invasive.

[Pulmonary complications following laparoscopic cholecystectomy in patients with abnormal spirometry]

The purpose of this study was to determine the incidence of postoperative pulmonary complications (PPC) and the value of preoperative spirometry to predict PPC after laparoscopic cholecystectomy. Sixty-four of 1372 patients (8%) showed abnormal spirometry data. One out of 1372 patients developed aspiration pneumonia. The patient had high risk factors for serious PPC such as ASA physical status 4.84 y/o, longer anesthesia duration (230 min), multiple brain infarction and low albuminemia. Thirty to 39% of patients with abnormal spirometry showed less severe PPC such as atelectasis, lung collapse and pleural effusion, and incidence was the similar with normal lung function patients. Postoperative blood gas analysis showed a slight increase in arterial carbon dioxide tension during oxygen therapy. However, none of the patients with abnormal spirometry and less severe PPC developed manifest PPC (pneumonia, respiratory failure). Less severe PPC disappeared within second to third postoperative days. We conclude that laparoscopic intervention significantly reduced the incidence of severe PPC and the preoperative spirometry was not recommended in patients with no pulmonary symptoms.

Cardiac arrest associated with use of an argon beam coagulator during laparoscopic cholecystectomy

We describe a cardiac arrest during use of an argon beam coagulation (ABC) system in an 82-yr-old woman having laparoscopic cholecystectomy under general and epidural anaesthesia. Intra-abdominal pressure (IAP) was controlled to less than 12 mm Hg during a carbon dioxide gas pneumoperitoneum and at first the operation was uneventful. When the ABC system (gas flow 6 litre min(-1)) was used to control local bleeding in the liver bed abdominal pressure increased rapidly to over 20 mm Hg and, 1 min later, the end-tidal carbon dioxide decreased to zero, followed by bradycardia and cardiac arrest. At once, an emergency laparotomy was performed and resuscitation begun. A mill-wheel murmur was heard on auscultation, leading to suspicion of argon gas embolism. Fortunately, recovery was completed with no neurological deficit. Anaesthesiologists should consider showed that argon gas embolism can occur with the ABC system during laparoscopic surgery.

[Resolution of overlapping chromatographic peaks by radial basis function neural network]

A new algorithm-resolution of overlapping chromatographic peaks by radial basis function neural network(RBFNN) is presented. A two-phase genetic algorithm(GA) which has robustness and random globe optimization is used to train RBFNN so that it has the ability on the resolution of overlapping chromatographic peaks. The two-phase genetic algorithm involves two procedures: training structure and optimizing parameter. The first procedure uses GA to train the architectures of RBFNN, the second procedure uses gradient descent to train the center(tR) and the width(sigma) of RBFNN. The alternate use of these two procedures makes the network having the ability to learn structure, therefore makes itself adaptable to resolution of the chromatographic peaks with unknown number of components. The method proposed here needs no artificial interference, not only has it robustness and globalism, but also the ability of accurate resolution to completely overlapped chromatographic peaks. The simulation experiments show that this method is more accurate than other methods.

Causes of airway obstruction during cuffed oropharyngeal airway use

This study investigated the cause for needing airway maneuvers to maintain a patent airway during the use of cuffed oropharyngeal airway (COPA). Twenty adult patients (29.4+/-6.8 years-old, ASA 1-2) scheduled for minor gynecological surgery who required brief manipulations of the airway despite COPA use following the manufacture's guidelines, were enrolled in this study. To obtain airway patency, 15 patients required only the head-tilt maneuver. In eight of the 15 patients, the laryngeal inlet was opened partially (n=4) or completely (n=4). Despite lifting the epiglottis, the laryngeal inlet was incomplete at the level of pharyngeal view. The patency of the laryngeal inlet was decided by the extent of the distance between the posterior pharyngeal wall and the lateral glossoepiglottic fold, which was made by hyoid bone. In the other seven patients, the head-tilt maneuver elevated the epiglottis and completely opened the laryngeal inlet. Five patients required both the jaw-thrust and head-tilt maneuver. Of these patients lifting the epiglottis was incomplete in three and the laryngeal inlet was partially collapsed in one even after the airway manipulations. The airways in these three patients, however, became patent after manipulations despite the persisting partial obstruction.

The 100-kda U5 snRNP protein (hPrp28p) contacts the 5' splice site through its ATPase site

To identify splicing factors in proximity of the 5' splice site (5'SS), we followed a crosslinking profile of site-specifically modified, photoreactive RNA substrates. Upon U4/U5/U6 snRNP addition, the 5'SS RNA crosslinks in an ATP-dependent manner to U6 snRNA, an unidentified protein p27, and the 100-kDa U5 snRNP protein, a human ortholog of an ATPase/RNA helicase yPrp28p. The 5'SS:hPrp28p crosslink maps to the highly conserved TAT motif in proximity of the ATP-binding site in hPrp28p. We propose that hPrp28p acts as a helicase to unwind the 5'SS:U1 snRNA duplex, and at the same time as a 5'SS translocase, which, upon NTP-dependent conformational change, positions the 5'SS for pairing with U6 snRNA within the spliceosome. This repositioning of the 5'SS takes place regardless of whether the 5'SS is originally duplexed with U1 snRNA.

The protooncogene TCL1 is an Akt kinase coactivator

Human T cell prolymphocytic leukemia can result from chromosomal translocations involving 14q32.1 or Xq28 regions. The regions encode a family of protooncogenes (TCL1, MTCP1, and TCL1b) of unknown function. In yeast two-hybrid screening, we found that TCL1 interacts with Akt. All TCL1 isoforms bind to the Akt pleckstrin homology domain. Both in vitro and in vivo TCL1 increases Akt kinase activity and as a consequence enhances substrate phosphorylation. In vivo, TCL1 stabilizes the mitochondrial transmembrane potential and enhances cell proliferation and survival. In vivo, TCL1 forms trimers, which associate with Akt. TCL1 facilitates the oligomerization and activation of Akt. Our data show that TCL1 is a novel Akt kinase coactivator, which promotes Akt-induced cell survival and proliferation.

[A nationwide survey of anesthesia for laparoscopic and thoracoscopic surgeries]

This is the report the first nationwide survey of anesthetic management for laparoscopic and thoracoscopic surgeries. We mailed a questionnaire to anesthetists of 133 hospitals in Japan and 74 completed questionnaires were returned. The number of intra-abdominal and thoracic surgical procedures has been increasing. General anesthesia was used in all cases for endoscopic surgery. The double lumen tube was selected in 79% of patients with pneumothorax for the endobronchial intubation. Patients for the laparoscopic cholecystectomy (LC) were given various types of anesthetics. Thirty-two percent of patients who underwent LC was anesthetized with inhalation anesthetics combined with epidural anesthesia for the early ambulance and postoperative pain control. The maximum length of time for LC surgery was 12.5 hr. Complications related to laparoscopic surgery included bile duct injuries in 72 patients, postoperative bleeding in 32 patients, vascular injuries in 29 patients, pneumothorax in 26 patients, bronchial intubation in 17 patients, gas embolism in 11 patients, bowel injuries in 9 patients and postoperative ileus in 7 patients. Administering anesthesia for endoscopic procedures requires precise knowledge of the surgical procedures, physiologic changes and complications of the pneumoperitoneum, and one lung ventilation.

Competitive lipase-catalyzed ester hydrolysis and ammoniolysis in organic solvents; equilibrium model of a solid-liquid-vapor system

Enzymatic ester hydrolysis and ammoniolysis were performed as competitive reactions in methyl isobutyl ketone without a separate aqueous phase. The reaction system contained solid ammonium bicarbonate, which dissolved as water, ammonia, and carbon dioxide. During the reaction an organic liquid phase, a vapor phase, and at least one solid phase are present. The overall equilibrium composition of this multiphase system is a complex function of the reaction equilibria and several phase equilibria. To gain a quantitative understanding of this system a mathematical model was developed and evaluated. The model is based on the mass balances for a closed batch system and straightforward relations for the reaction equilibria and the solubility equilibria of ammonium bicarbonate, the fatty acid ammonium salt, water, ammonia, and carbon dioxide. For butyl butyrate as a model ester and Candida antarctica lipase B as the biocatalyst this equilibrium model describes the experiments satisfactorily. The model predicts that high equilibrium yields of butyric acid can be achieved only in the absence of ammoniolysis or in the presence of a separate water phase. However, high yields of butyramide should be possible if the water concentration is fixed at a low level and a more suited source of ammonia is applied.

[Perioperative pulmonary embolism: a nationwide survey in Japan]

Pulmonary embolism is a leading cause of death and morbidity in the perioperative period. To obtain a contemporary overview of the epidemiology of acute pulmonary embolism, a questionnaire was mailed to anesthesia department chair-persons at 179 hospitals in Japan. The 158 cases were reported from the 88 hospitals. The cause of embolism was thromboembolism 127, gas 13, fat 9, amniotic fluid 4 and tumor 3. The mortality rate for patients with thromboembolism was high (29%). Dyspnea was the most frequent symptom (60%) and hypotension was the most frequent clinical sign (54%). The signs which suggested massive pulmonary embolism, such as hypotension, cyanosis (53%), syncope (39%) and cardiac arrest (29%) were frequently seen. Most of the pulmonary embolisms occurred during the operation and within 7 days after the operation. The high risk factors associated with thromboembolism were age, malignancy, obesity and the type of surgery performed. Treatment performed included anticoagulation 81%, catecholamine infusion 66%, thrombolysis 14%, surgical embolectomy 8% and extra-corporeal circulation 4%. This study indicates that the perioperative pulmonary embolism is still associated with high mortality and requires an immediate diagnosis and intensive therapy.

[Determination of columbianetin, columbianetin acetate and osthol in Angelica pubescens Maxim. f. biserrata Shan et Yuan by HPLC]

OBJECTIVE

To develop a method for the determination of columbianetin, columbianetin acetate and osthol in Angelica pubescens f. biserrata

METHOD

HPLC method, ODS column (6.0 mm x 150 mm) with a mobile phase of methanol-acetonitrile-0.025 mol.L-1 phosphoric acid (32:20:48), and wave length detection at 320 nm.

RESULT AND CONCLUSION

The method can be used for the quality control of raw medicinal materials.

[Determination of gallic acid in garden burnet by HPLC]

OBJECTIVE

To establish a HPLC method for the determination of gallic acid in garden burnet.

METHOD

The sample was extracted with methanol under ultrasonic management for 25 min. Chromatographic conditions: Shimadzu LC-6A with SPD-6AV detector at 270 nm and auto injector SIL-6A, methanol-0.025 mol/L phosphoric acid(15:85) as the mobile phase. Shin-pack CLC-ODS column(6.0 mm x 15 mm).

RESULT

Gallic acid in garden burnet was baseline separated and determined. The average content was 0.22%, recovery rate 97.4% and relative standard deviation 1.3%.

CONCLUSION

Simple, rapid and accurate, the method provides new indexes for quality control of Garden Burnet.

Probing of the spliceosome with site-specifically derivatized 5' splice site RNA oligonucleotides

We have developed a site-specific chemical modification technique to incorporate a photoreactive azidophenacyl (APA) group at designated internal positions along the RNA phosphodiester backbone. Using this technique, we have analyzed interactions of the 5' splice site (5'SS) RNA within the spliceosome. Several crosslinked products can be detected within complex B using the derivatized 5'SS RNAs, including U6 snRNA, hPrp8p, and 114-, 90-, 70-, 54-, and 27-kDa proteins. The 5'SS RNAs derivatized at intron positions +4 to +8 crosslink to U6 snRNA, confirming the previously reported pairing interaction between these sequences. hPrp8p and p70 are crosslinked to the 5'SS RNA when the APA is placed within the 5' exon. Finally, a set of unidentified proteins, including p114, p54, and p27, is detected with the 5'SS RNA derivatized at intron positions +4 to +8. Introduction of the bulky APA group near the 5'SS junction (positions -2 to +3) strongly interferes with complex B formation and thus no APA crosslinks are observed at these positions. Together with our earlier observation that hPrp8p crosslinks to the GU dinucleotide at the 5' end of the intron, these results suggest that the inhibitory effect of APA results from steric hindrance of the hPrp8p:5'SS interaction. Unexpectedly, thio-modifications within the region of the 5'SS RNA that is involved in base pairing to U6 snRNA strongly stimulate complex B formation.

Preoperative nocturnal desaturations as a risk factor for late postoperative nocturnal desaturations

Severe postoperative hypoxaemia during sleep may increase the risk of postoperative cardiovascular complications. We hypothesized that the severity of hypoxic episodes after surgery are related to the presence of preoperative sleep-disordered breathing (SDB). We tested this hypothesis in a multicentre study designed to elucidate the major risk factors for development of postoperative nocturnal desaturations. We performed overnight oximetry before operation and for one night between the second and fourth day after operation in 80 patients undergoing major surgery. We calculated oximetry variables such as oxygen desaturation index (ODI), defined as the number of oxygen desaturations exceeding 4% below baseline, percentage time spent at SpO2 < 90% (CT90, %) and lowest SpO2 value. After operation, although the change in ODI was not significant (P = 0.34), deterioration in CT90 and lowest SpO2 values were significant (P = 0.036 and P = 0.007, respectively). Multivariate analysis of possible risk factors for postoperative desaturations revealed that preoperative hypoxaemia and apnoea witnessed by others were highly correlated with postoperative hypoxaemia.

[Determination of hyperin in Sanguisorba Officinalis L. by high performance liquid chromatography]

An HPLC method for the determination of hyperin in Sanguisorba officinalis L. was investigated. 0.5 g of dried powdered crude drug was weighed accurately in a 50 mL volumetric flask added with 40 mL methanol, supersonicated for 30 min and then made up to volume with methanol. The sample solution was separated on a Shim-pack ODS column(6.0 mm i.d. x 150 mm, 5 microns) with methanol-0.025 mol/L phosphoric acid (adjusted to pH 3.0 by using triethylamine)(50:50) as the mobile phase and detected at UV-370 nm. Calibration curve of hyperin was obtained for the concentration range of 0.046-0.2 microgram. The corresponding regression equation was Y = 154 x 10(4) X-0.28 x 10(4), r = 0.9998. The recovery was 98.7% and relative standard deviation was 1.9%. The results showed that this method is simple, specific and accurate.

Baculovirus-mediated expression and characterization of the full-length murine DNA methyltransferase

The original cDNA sequence reported for the murine DNA methyltransferase (MTase) was not full length. Recently, additional cDNA sequences have been reported that lie upstream of the original and contain an extended open reading frame with three additional ATGs in frame with the coding region [Tucker et al . (1996) Proc. Natl. Acad. Sci. USA , 93, 12920-12925; Yoder et al . (1996) J. Biol. Chem . 271, 31092-31097]. Genomic DNA upstream of this ATG contains two more ATGs in frame and no obvious splice site. We have constructed, and expressed in baculovirus, MTase clones that begin at each of these four ATGs and examined their properties. Constructs beginning with any of the first three ATGs as their initiator methionines give a predominant DNA MTase band of approximately 185 kDa on SDS-PAGE corresponding to translational initiation at the third ATG. The fourth ATG construct gives a much smaller protein band of 173 kDa. The 185 kDa protein was purified by HPLC, characterized by mass spectrometry and has a measured molecular mass of 184 +/- 0.5 kDa. All of these MTases were functional in vitro and steady state kinetic analysis showed that the recombinant proteins exhibit similar kinetic properties irrespective of their length. The homogeneous recombinant enzyme from the fourth ATG construct shows a 2.5-fold preference for a hemi-methylated DNA substrate as compared to an unmethylated substrate, whereas the 185 kDa protein is equally active on both substrates. The kinetic properties of the recombinant enzyme are similar to those reported for the native MTase derived from murine erythroleukemia cells. The new clones are capable of yielding large quantities of intact MTases for further structural and functional studies.

Molecular analysis of a novel winged helix protein, WIN. Expression pattern, DNA binding property, and alternative splicing within the DNA binding domain

We have cloned a novel winged helix factor, WIN, from the rat insulinoma cell line, INS-1. Northern blot analysis demonstrated that WIN is highly expressed in a variety of insulinoma cell lines and rat embryonic pancreas and liver. In adults, WIN expression was detected in thymus, testis, lung, and several intestinal regions. We determined the DNA sequences bound in vitro by baculovirus-expressed WIN protein in a polymerase chain reaction-based selection procedure. WIN was found to bind with high affinity to the selected sequence 5'-AGATTGAGTA-3', which is similar to the recently identified HNF-6 binding sequence 5'-DHWATTGAYTWWD-3' (where W = A or T, Y = T or C, H is not G, and D is not C). We have isolated human WIN cDNAs by library screening and 5'-rapid amplification of cDNA ends. Sequence analysis indicates that the carboxyl terminus of human WIN has been previously isolated as a putative phosphorylation substrate, MPM2-reactive phosphoprotein 2 (MPP2); WIN may be regulated by phosphorylation. Alignment of the rat and human WIN cDNAs and their comparison with mouse genomic sequence revealed that the WIN DNA binding domain is encoded by four exons, two of which (exons 4 and 6) are alternatively spliced to generate at least three classes of mRNA transcripts. These transcripts were shown by RNase protection assay to be differentially expressed in different tissues. Alternative splicing within the winged helix DNA binding domain might result in modulation of DNA binding specificity.

[Determination of eugenol, methyleugenol and methylisoeugenol in volatile oil of differently processed nutmeg]

A HPLC method for the determination of eugenol, methyleugenol and methylisoeugenol in the volatile oil of differently processed natmeg has been used. The result has shown that the content of eugenol is only sliahtly changed before and after processing, but that of methyleugenol and methylisoeugenol has obviously increased.

[Determination of myristicin and safrol in volatile oil of nutmeg and its processed products by HPLC]

The contents of myristicin and safrol in the volatile oil of nutmeg and its processed products were determined by HPLC. This method is fast, accurate and gives good resolution. It has also been confirmed that myristicin tends to decrease in varying degrees after the nutmeg has been processed.

RNA aptamers that specifically bind to a K Ras-derived farnesylated peptide

RNA aptamers were selected against an affinity column containing a farnesylated peptide modeled after the carboxyl terminus of K ras, the major oncogenic form of this small G protein family. After 10-rounds of selection, 25% of the RNA applied to the column could be specifically eluted. Sequence analysis of the binding RNA aptamers revealed two consensus sequences--GGGUGGG and GGGAGG. Quantitative fluorescence binding studies on two of the high-affinity aptamers, showed a binding affinities of 139 nM and 0.93 microM, respectively for the farnesylated peptide. Binding to the nonfarnesylated peptide was at least 10-fold weaker, showing that the aptamers can recognize the hydrophobic farnesyl moiety. High affinity aptamers could be useful in specifically interfering with oncogenic ras function in particular, and G proteins in general.

[Determination of icariin in Epimedium koreanum nakai by high performance liquid chromatography]

An HPLC method for determination of icariin in epimedium koreanum nakai was investigated. The results showed that this method was simple, specific and accurate. The recovery was 97.6% and relative standard deviation was 1.2%. About 0.5 g of dried powdered crude drug was weighed accurately, placed in 25 mL of the mobile phase and refluxed on a water-bath for 30 min. After cooling, the solution was decanted. The residue was refluxed twice with 10 mL of the mobile phase. The extract were placed in a 50 mL volumetric flask and diluted to 50 mL with the mobile phase. A 3 microL of the solution was injected into the HPLC system. Linear calibration graphs for icariin were obtained for the concentration ranges of 0.08-0.4 microg. HPLC conditions were used was Shimadzu LC-6A with UV spectrometric detector SPD-6AV; at 270 nm and auto injector SIL-6A. Water-acetonitrile (70:30) as the mobile phase, Shim-pack CLC-ODS column (6.0 mm x 150 mm).

[Determination of chrysophanol in semen Cassiae by HPLC]

A HPLC method for the determination of chrysophanol in Semen Cassiae was investigated. The result showed that this method was simple, specific and accurate. The recovery was 99.0% and relative standard deviation was 1.8%. The method is useful for the quality control of this medicinal meaterial.

[Quantitative study of magnoflorine in Epimedium koreanum Nakai]

The content of magnoflorine in different parts of Epimedium koreanum was determined by using HPLC. The results showed that magnoflorine existed in every part of the plant and the highest content was found in the rhizoma. A new index and a reliable method are correspondingly provided for the quality control of E. koreanum.

pH-dependent and ligand induced conformational changes of eucaryotic protein synthesis initiation factor eIF-(iso)4F: a circular dichroism study

The structural features of wheat germ protein synthesis initiation factor eIF-(iso)4F, which has a cap binding protein as one of its two subunits, are unknown. In this study, circular dichroism (CD) spectra and secondary structure prediction were obtained for eIF-(iso)4F and its two subunits, p28 and p86. The alpha-helix content of eIF-(iso)4F changed from 42% at pH 6.3 to 15% at pH 7.6, the optimum pH for cap binding. The beta-sheet content increased from 14% (pH 6.3) to 38% at pH 7.6. The CD spectra of the two subunits, p28 and p86 were also measured and analyzed. The separated subunits both had a higher alpha-helix content at pH 7.6 than the native protein, giving values of 60% and 34% alpha-helix for p28 and p86, respectively. Binding of the dinucleotide cap analog to p28 reduced the alpha-helix content to approximately 8% with an increase in the beta sheet content from 10% to 37%. The conformational changes in eIF-(iso)4F upon binding with mRNA are dependent on cap or oligonucleotide structure. A conformation consisting of approximately the same alpha-helix and beta-sheet content can be induced by ligands even at non-optimal pH values. This large conformational transition suggests eIF-(iso)4F binds nucleic acids by interaction of a beta-sheet motif and that this conformational transition may have a regulatory role.

[Quantitative changes of flavonoids in Epimedium koreanum Nakai in different collecting periods]

The quantitative changes of flavonoids in Epimedium koreanum in different collecting periods were determined by HPLC and UV spectrophotometry. The result shows that the highest content of flavonoids is found in the flowering period (May).

[Determination of chlorogenic acid in Epimedium koreanum Nakai by HPLC]

The chlorogenic acid content in Epimedium koreanum was determined by HPLC. The result shows that this method is simple, specific and accurate. The recovery was 97.5% and relative standard deviation was 1.4%. With good reproducibility and wide response linearity, the method can be used for the quality control of this herbal medicine.

Interaction of wheat germ protein synthesis initiation factor eIF-(iso)4F and its subunits p28 and p86 with m7GTP and mRNA analogues

The binding of p28, p86, and native wheat germ eIF-(iso)4F with m7GTP and oligonucleotides was measured and compared. The purified subunits (p28, 28 kDa and p86, 86 kDa) of wheat germ protein synthesis initiation factor eIF-(iso)4F have been obtained from Escherichia coli expression of the cloned DNA (van Heerden, A., and Browning, K. S. (1994) J. Biol. Chem. 269, 17454-17457). The binding of the 5'-terminal cap analogue m7GTP to the small subunit (p28) of eIF-(iso)4F as a function of pH, temperature, and ionic strength is described. The mode of binding of p28 to cap analogues is very similar to the intact protein. Assuming that all tryptophan residues contribute to p28 and eIF-(iso)4F fluorescence, iodide quenching shows that all 9 tryptophan residues in p28 are solvent-accessible, while only 6 out of 16 tryptophan residues are solvent-accessible on the intact eIF-(iso)4F. The fluorescence stopped-flow studies of eIF-(iso)4F and p28 with cap show a concentration-independent conformational change. The rate of this conformational change was approximately 10-fold faster for the isolated p28 compared with the native eIF-(iso)4F. From these studies it appears that cap recognition resides in the p28 subunit. However, p86 enhances the interaction with capped oligonucleotides and probably is involved in protein-protein interactions as well. Both subunits are required for helicase activity.

[A case of sudden death during postoperative Holter ECG examination in a patient who experienced intraoperative cardiac arrest]

We report a case of postoperative sudden death during Holter-ECG examination in a 62-yr-old male, who experienced intraoperative cardiac arrest possibly due to myocardial ischemia. Although the patient recovered from intraoperative event without any neurological sequelae, he suffered from spontaneous ventricular tachycardia following mild ST segment depression that led to cardiac arrest on the 58th postoperative day. Precise mechanism of sudden death was not clear because coronary angiography or autopsy was not performed. However, the postoperative Holter-ECG revealed frequent episodes of silent 0.5-1.0 mm ST segment depression during tachycardia which had not been observed in the preoperative 12-lead ECG. Thus a likely explanation would be that the patient had the undetected coronary artery disease with frequent episodes of silent ischemia and finally was led to the fatal arrhythmia. In this case, so called "stunned myocardium" following repeated silent ischemia may have also contributed to the life-threatening arrhythmias. This case suggests that even mild ST depression might lead to life-threatening arrhythmias in the patients with silent ischemia. Adequate preoperative evaluation and careful perioperative observation are necessary for these patients.

[A case of inspiratory unidirectional value malfunction detected by an abnormal capnogram pattern]

We report a case of substantial rebreathing which occurred during the thoracoscopic bulla resection despite a normal FICO2 reading on capnogram. Early detection of inspiratory unidirectional valve malfunction as the cause of the rebreathing was only possible by careful observation of the capnogram pattern. During the course of one lung anesthesia, a rising end-tidal CO2 concentration (FETCO2) and a change in the pattern of the capnogram were observed. However, the lowest FICO2 value in the late phase of inspiration stayed below the alarm limit setting of rebreathing. For this reason, the capnograph failed to identify the beginning of inspiration and perceived the high FICO2 value in early inspiration as part of expiratory plateau. In case of the inspiratory valve malfunction, it is possible that analysis of the capnogram reveals underestimated FICO2.

How far can we go with permissive hypercapnia? A case presentation and some biased comments with emphasis on maintaining normal haemoglobin level

The respiratory management strategy of small tidal volume with permissive hypercapnia has been adopted to avoid further aggravation of lung injury due to high airway pressure with some impressive success (1). No consensus, however, has been established in terms of the rate of increase in PaCO2 and its upper limit. Recently, our colleague in the intensive care unit experienced a severe case of ARDS successfully treated with the above strategy despite of the fact that during the course of treatment, the highest PaCO2 reached 177 mmHg and the lowest pH, 7.03 (2). The fact that PaCO2 may reach a very high level in the clinical setting and the well-known role of haemoglobin (Hb) in buffering CO2 led us to study effects of different Hb levels on pH and haemodynamic changes in response to acute CO2 loading in the blood. We will summarize the case report first with permission of authors (the case report was published in Japanese) (2) and then discuss the studies conducted in our animal laboratory.

Anti-cooperative biphasic equilibrium binding of transcription factor upstream stimulatory factor to its cognate DNA monitored by protein fluorescence changes

Upstream stimulatory factor USF is a human transcriptional activation factor, which uses a basic/helix-loop-helix/ leucin zipper (b/HLH/Z) motif to homodimerize and recognize specific sequences in the promoter region of both nuclear and viral genes transcribed by RNA polymerase II. Steady state fluorescence spectroscopy demonstrated that the basic/helix-loop-helix/leucin zipper domain of USF binds its DNA targets with high affinity and specificity, whereas removal of the leucine zipper yielding the basic/helix-loop-helix minimal DNA binding region reduces both affinity and specificity. Stopped flow method provided kinetic evidence for a two-step binding process involving rapid formation of a protein-DNA intermediate followed by a slow isomerization step, which is consistent with the basic region undergoing a random coil to alpha-helix folding transition on specific DNA recognition. The leucine zipper is also necessary for USF to function as a bivalent homotetramer, capable of binding two distinct recognition sites simultaneously and mediating DNA looping under physiologic conditions. Titration studies revealed that the first binding event has a equilibrium constant Keq = (2.2 +/- 2.0) x 10(9) M-1 for major late promoter DNA, whereas the second binding event occurs with a remarkable reduced affinity, Keq = (1.2 +/- 0.8) x 10(8) M-1. This anticooperative feature of DNA binding by the homotetramer suggests that USF stimulates transcription by mediating DNA looping between nearby recognition sites located in class II nuclear and viral gene promoters.

Aberrant expression of the myeloid zinc finger gene, MZF-1, is oncogenic

The zinc finger gene MZF-1 is preferentially expressed in primitive hematopoietic cells and plays an important role in regulating myelopoiesis. Regulators of development are potential targets for neoplastic transformation. This study investigated whether unregulated expression of MZF-1 could function as an oncogene. Retroviral transduction and subsequent overexpression of MZF-1 resulted in loss of contact inhibition, loss of substrate dependence, and more rapid cell cycling in NIH 3T3 cells. The MZF-1-transformed 3T3 cells formed aggressive tumors in athymic mice. Disruption of the tight lineage- and stage-specific regulation of MZF-1 can result in neoplastic transformation of embryonic fibroblasts. Therefore, MZF-1 represents a novel oncogene.

[Determination of hyperin in Epimedium koreanum Nakai by HPLC]

A HPLC method for the determination of hyperin in Epimedium koreanum was investigated. The result shows that this method is simple, specific and accurate. The recovery was 97.4% and relative standard deviation was 1.2%. With good reproducibility and wide response linearity, the method can be used for the quality control of this herbal medicine.

An interaction of wheat germ initiation factor 4B with oligoribonucleotides

The binding of oligoribonucleotides to wheat germ protein synthesis initiation factor eIF-4B was measured by direct fluorescence techniques. An analysis of the equilibrium association constants (Keq) indicates that eIF-4B binding is not affected by the m7GTP cap structure or the AUG. eIF-4B is insensitive to hairpin structures within the oligoribonucleotide. The binding site size is approximately 18 bases. The binding of oligoribonucleotide to eIF-4B as a function of pH, temperature, and ionic strength is also described. The pH-dependent binding showed an increase in binding with increasing pH in contrast to the sharp pH optimum observed for cap binding protein eIF-4E (Carberry, S. E., Darzynkiewicz, E., and Goss, D.J. (1991) Biochemistry 30, 1624-1627). Assuming all tryptophan residues contribute to the observed fluorescence, iodide quenching showed that 8(+/- 1) out 9 of eIF-4B's tryptophan residues are on the surface of the eIF-4B protein. A specific anion effect of Cl- on eIF-4B binding to oligoribonucleotide was found when comparing the ionic strength effect of KC2H3O2 and KCl.

[Power spectrum of experimental gas embolism in dogs and a new device for its detection]

We studied the power spectrum of precordial Doppler sounds during experimental CO2 and air embolism and developed a new device for detection (intravascular gas detector) and examined its usefulness in experimental CO2 and air embolism in dogs and in a patient during laparoscopic surgery. We did digital tape recordings during CO2 and air embolism in seven anesthetized mongrel dogs (7-16 kg body) to generate power spectrum of the heart sound on a dynamic signal analyzer. The power spectrum of "mill-wheel murmur" was found to be 10-30 dB higher than the baseline heart sound in the range of 200 and 2500 Hz. The intravascular gas detector was designed to set off alarm sounds whenever the difference of energy between the Doppler sounds low-pass filtered at 250 Hz and the Doppler sounds high-pass filtered at 250 Hz was increased. The alarm was activated immediately during experimental CO2 and air embolism and also during laparoscopic appendectomy. The alarm sounds during the appendectomy coincided with gas bubbles detected by a transesophageal echocardiography. By use of this detector, CO2 and air embolism can be easily detected and the anesthesiologist does not need to pay continuous attention to Doppler sounds by diverting his or her concentration on the patient.