Docking domains and substrate-specificity determination for MAP kinases

Signalling specificity in eukaryotic cells is maintained by several mechanisms. One mechanism by which mitogen-activated protein (MAP) kinases ensure their specificity of action is by interacting with their substrates through docking domains. These docking domains recruit the kinases to the correct substrates and enhance their fidelity and efficiency of action. Additional specificity determinants in the substrates serve to enhance the specificity of substrate phosphorylation by MAP kinases further.

The amino-terminal region of the fusion peptide of influenza virus hemagglutinin HA2 inserts into sodium dodecyl sulfate micelle with residues 16-18 at the aqueous boundary at acidic pH. Oligomerization and the conformational flexibility

The conformation and interactions with membrane mimics of the NH(2)-terminal fragment 1-25 of HA2, HA2-(1-25), of influenza virus were studied by spectroscopic methods. Secondary structure analysis of circular dichroism data revealed 45% helix for the peptide at pH 5.0. Tryptophan fluorescence quenching by acrylamide and NMR experiments established that the Trp(14) is inside the vesicular interior and residues 16-18 are at the micellar aqueous boundary. NBD fluorescence enhancement of the NH(2)-terminal labeled fluorophore on the vesicle-bound peptide indicated that the NH(2) terminus of the fusion peptide was located in the hydrophobic region of the lipid bilayer. No significant change in insertion depth was observed between pH 5.0 and 7.4. Collectively, these spectroscopic measurements pointed to an equilibrium between helix and non-helix conformations, with helix being the dominant form, for the segment in the micellar interior. The conformational transition may be facilitated by the high content of glycine, a conformationally flexible amino acid, within the fusion peptide sequence. Self-association of the 25-mer peptide was observed in the N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine SDS-gel electrophoresis experiments. Incorporating the NMR signal attenuation, fluorescence, and gel electrophoresis data, a working model for the organization of the fusion peptide in membrane bilayers was proposed.

Cecal volvulus: report of seven cases and literature review

BACKGROUND

Cecal volvulus is an abdominal emergency and delay in its diagnosis and treatment can result in severe complications. We reviewed these cases in order to increase the understanding of cecal volvulus (CV) to promote early diagnosis and better management.

METHODS

In this retrospective study of seven patients (all male; mean age +/- standard deviation, 63.4 +/- 17.3 years) over a 16-year period, we reviewed radiographs, for diagnostic accuracy, and the results of surgical procedures for better future management.

RESULTS

The symptoms of CV related to obstruction had a mean of duration of 6.85 days (range, 2-20 days). The preoperative diagnosis rate was 57.1%. Three types of CV (bascule, clockwise and counterclockwise) were found. There were three treatment failures resulting in two deaths. There were two cases of metachronous volvulus, one in the sigmoid colon and one in the small intestine.

CONCLUSIONS

Resection is indicated for gangrene or perforation and is highly suggested in underlying bowel disease or recurrent operative procedures. For uncomplicated viable CV, cecopexy provides fair results. Metachronous volvulus should always be considered when obstruction recurs.

Overexpression of rapsyn modifies the intracellular trafficking of acetylcholine receptors

Rapsyn is a protein that interacts with the cytoplasmic face of the nicotinic acetylcholine receptors (AChR) to cluster them within postsynaptic membrane of muscle. Here we show that intracellular AChRs are also affected by rapsyn. When rapsyn was co-transfected with AChR into QT-6 fibroblasts, (125)I-alpha-bungarotoxin binding indicated a reduction in the fraction of AChRs expressed on the cell surface, compared to cells expressing AChRs alone. Double fluorescent labeling showed that intracellular AChRs accumulated in patches at the cell periphery, beneath rapsyn-associated cell surface AChR clusters. These patches were observed even when cells were grown in medium containing excess unlabelled alpha-bungarotoxin to mask internalized AChRs, suggesting that they arose from hindered trafficking of newly formed AChRs to the cell surface. Similarly, in the muscle cell line, C2, overexpression of rapsyn resulted in the co-localization of aggregates of intracellular alpha-bungarotoxin binding sites with rapsyn beneath cell surface AChR microaggregates. The results indicate that rapsyn can modify the trafficking of AChRs within the cell and suggest a role in selectively targeting newly synthesized intracellular AChRs to the postsynaptic membrane.

A helix initiation motif, XLLRA, is stabilized by hydrogen bond, hydrophobic and van der Waals interactions

Five partially overlapping synthetic peptides containing the N-terminal portion of the leucine zipper (LZ)-like domain of human immunodeficiency virus envelope glycoprotein gp41 were used to deduce the helix initiation site. Circular dichroism (CD) data suggested a strong helix-inducing motif, LLRA. The coupling constant and nuclear Overhauser effect (NOE) results obtained from nuclear magnetic resonance experiments in 20% trifluoroethanol aqueous solution at 280 K for the four decapeptides under study suggested that the motif XLLRA, where X is a group or an amino acid residue capable of forming hydrogen bond to arginine, constitutes a helix nucleation core. A similar conclusion was reached for a pentadecapeptide in water, suggesting that the result was not dependent on both chain length and the helix promoting medium. Detailed analysis of NOE and CD data from the four decapeptides indicated that the acetyl group and asparagine had a strong tendency to be helix N-capping, in confirmation of previous studies. Molecular modeling using restraints derived from NOE data showed that van der Waals, hydrophobic interactions and hydrogen bonds contribute synergetically to the stability of the core structure. The concept of nucleation core consisting of a few amino acids may be generally applied in proton design and folding studies.

Estradiol exerts neuroprotective effects when administered after ischemic insult

BACKGROUND AND PURPOSE

17beta-Estradiol (E2) has been reported to exert neuroprotective effects when administered before an ischemic insult. This study was designed to determine whether E2 treatment after ischemia exerts the same effects and, if so, how long this therapeutic window remains open, and whether the effects are related to changes in cerebral blood flow (CBF).

METHODS

Female Sprague-Dawley rats were subjected to permanent middle cerebral artery occlusion (MCAO). In protocol 1, E2 was administered (100 microg/kg IV followed immediately by subcutaneous implantation of crystalline E2 in a silicone elastomer tube) to ovariectomized females (OVX+E2) at 0.5 (n=8), 1 (n=6), 2 (n=7), 3 (n=6), or 4 (n=9) hours after MCAO. Intact (INT; n=6) and ovariectomized females (OVX; n=12) were subjected to MCAO and received vehicle instead of E2. Two days after MCAO the animals were killed, and ischemic lesion volume was determined by 2,3,5-triphenyltetrazolium chloride staining. In protocol 2, CBF was monitored before and at 1, 24, and 48 hours in a group of animals receiving E2 or vehicle 0.5 hour after ischemia induction (INT, n=6; OVX, n=8; OVX+E2, n=6).

RESULTS

Lesion volume was 20.9+/-2.2% and 21.8+/-1.2% in the INT and OVX groups, respectively. E2 was found to decrease lesion volume significantly when administered within 3 hours after MCAO. The lesion volumes were 6.3+/-0.5%, 10.3+/-2.1%, 11.8+/-1.8%, 13.5+/-1.6%, and 17.9+/-2.8% when E2 was administered at 0.5, 1, 2, 3, or 4 hours after MCAO, respectively. CBF decreased to 43.1+/-2.2% and 25.4+/-1.0% in the INT and OVX animals, respectively, at 5 minutes after MCAO. In comparison to OVX rats, CBF was not different at 1 hour after E2 administration but was increased significantly in the OVX+E2 group 1 and 2 days after E2 administration.

CONCLUSIONS

E2 exerts neuroprotective effects when administered after ischemia, with a therapeutic window in a permanent focal cerebral ischemia model of approximately 3 hours. This effect of estradiol was associated with no immediate change in blood flow but with a delayed increase in CBF.

Internal cleavage of hepatitis C virus NS3 protein is dependent on the activity of NS34A protease

The nonstructural protein NS3 of the hepatitis C virus (HCV) is indispensable for virus replication and a multifunctional enzyme that contains three catalytic activities such as serine protease, helicase, and NTPase. Here, we demonstrated that the internal cleavage of the HCV NS3 protein occurs in various mammalian cells such as HepG2, COS-7, and NIH3T3. As is observed for the internal cleavage mechanism of the NS3 protein of dengue virus 2, the internal processing of HCV NS3 protein was catalyzed by the active NS3 serine protease and NS4A, but not NS3 alone. From the data acquired from extensive site-directed mutagenesis, we observed that the NS3 protein was internally cleaved at two different sites, FCH(1395) ||S(1396)KK and IPT(1428) ||S(1429)GD, within RNA helicase domain. The internal cleavage of NS3 protein by NS34A protease was also confirmed in a different isolate of HCV-1b strain. In addition, in vitro transforming assays demonstrated that the internal cleavage product of NS3, NS3a-1, appeared to have higher oncogenic potential than does intact NS3. Taken together, our results suggest that the internal cleavage of NS3 may be associated with the replication and oncogenesis of HCV.

Hypoperfusion induces overexpression of beta-amyloid precursor protein mRNA in a focal ischemic rodent model

Silent stroke is one of the risk factors of dementia. In the present study, we used a novel focal ischemic animal model to investigate the effects of comparatively small changes of cerebral blood flow (CBF) on the expression of beta-amyloid precursor protein (APP) mRNA. Focal ischemia was achieved by introducing a 4-0 monofilament to the bifurcation of anterior and middle cerebral arteries. Brain samples were harvested from ischemic core and penumbra of cortices at 1, 4 and 7 days following ischemia. The expression of APP mRNA was assessed by RT-PCR. The CBF was decreased to 50% for 1 day after stroke and recovered to 90% at the fourth day after stroke. The changes of CBF were accompanied by an increase in the expression of APP mRNA. APP mRNA increased to 208% and 152% in the penumbra and core ischemic regions, respectively, on the fourth day after MCAO and remained high through the seventh day of ischemia. This study suggests brain hypoperfusion enhances APP mRNA expression and may contribute to the progression of cognitive impairment after silent stroke.

Preoperative carcinoembryonic antigen level as an independent prognostic factor in colorectal cancer: Taiwan experience

BACKGROUND

Preoperative carcinoembryonic antigen (CEA) level is considered as a factor predictive of survival in colorectal cancer patients. Patients with normal (<5 ng/ml) or lower preoperative CEA levels were reported to have significantly longer survival. This study was carried out in an effort to evaluate the prognostic significance of preoperative CEA levels of patients with colorectal cancer in Taiwan.

METHODS

Between 1990 and 1994, 218 patients with histologically confirmed colorectal cancers were evaluated retrospectively at the Veterans General Hospital-Taipei. All the patients had undergone potentially curative surgery. Patients with metastatic diseases were not included. 5-Fluorouracil-based adjuvant chemotherapy was administered if the patients had Dukes' C disease. Reference to the Dukes' classification was according to the classical criteria described in 1932 for carcinoma of the rectum and adapted for use in colonic tumors. Data on gender, age, degree of tumor differentiation, location of the tumor, tumor size, lymph node metastasis, penetration of the bowel wall and preoperative CEA levels were analyzed to determine their association with survival. Blood samples for CEA measurement were taken a few days before operation and were analyzed using the radioimmunoassay method. Multivariate analysis by Cox's proportional hazards regression model was performed to determine the most important predictors of survival among all of the possible variables.

RESULTS

By univariate analysis, the size of the tumor (p = 0.012), lymph node metastases (p = 0.007), penetration of the bowel wall (p < 0.001) and preoperative CEA levels (p < 0.001) were found to be significant prognostic factors, while gender, age, degree of tumor differentiation and location of the tumor were not significant. By multivariate Cox analysis, lymph node metastases (p = 0.003), penetration of the bowel wall (p = 0.0001) and preoperative CEA levels (p = 0.0001) were found to be independent prognostic factors in colorectal cancer patients.

CONCLUSIONS

The data from our study indicate that in addition to lymph node metastases and penetration of the bowel wall, the preoperative CEA levels are also an independent prognostic factor in non-metastatic colorectal cancer patients after curative surgery. This could serve as an appropriate modification to the initial Dukes' scheme in colorectal cancer.

Molecular characterization of a zebrafish TCF ETS-domain transcription factor

The ternary complex factor (TCF) subfamily of ETS-transcription factors represent key nuclear targets of the MAP kinase pathways. Members of this subfamily are classified by the presence of several conserved domains for DNA binding, interaction with SRF, interaction with MAP kinases and transcriptional activation. In this study we have isolated a further member of this subfamily (TCF-1) from zebrafish. The protein product of zebrafish TCF-1 (zTCF-1), shares sequence similarity with the mammalian TCFs in all four conserved domains, with highest overall similarity to SAP-1. Zebrafish TCF-1 is expressed throughout zebrafish embryonic development and exhibits typical TCF DNA binding characteristics, with the B-box being required for interaction with SRF. Of the mammalian TCFs, its DNA binding specificity resembles Elk-1. zTCF-1 is a target for both the growth factor/mitogen-activated and stress-activated MAP kinase cascades in vitro and in vivo. However, differential targeting occurs, with the profile of its activation closely resembling that of mammalian SAP-1. Together, our results demonstrate that the TCFs have been functionally conserved during vertebrate development.

TATA element recognition by the TATA box-binding protein has been conserved throughout evolution

Cocrystal structures of wild-type TATA box-binding protein (TBP) recognizing 10 naturally occurring TATA elements have been determined at 2.3-1.8 A resolution, and compared with our 1.9 A resolution structure of TBP bound to the Adenovirus major late promoter (AdMLP) TATA box (5'-TATAAAAG-3'). Minor-groove recognition by the saddle-shaped protein induces the same conformational change in each of these oligonucleotides, despite variations in promoter sequence that reduce the efficiency of transcription initiation. Three molecular mechanisms explain assembly of diverse TBP-TATA element complexes. (1) T --> A and A --> T transversions leave the minor-groove face unchanged, permitting formation of TBP-DNA complexes on many A/T-rich core promoter sequences. (2) Cavities in the interface between TBP and the minor-groove face of the AdMLP TATA box accommodate the exocyclic NH(2) groups of G in a TACA box and in a TATAAG box. (3) Formation of a C:G Hoogsteen basepair in a TATAAAC box eliminates steric clashes that would be produced by the Watson-Crick base pair. We conclude that the structure of the TBP-TATA box complex found at the heart of the polymerase II (pol II) transcription machinery has remained constant over the course of evolution, despite variations in TBP and its DNA targets.

Effects of acupuncture on exercise-induced muscle soreness and serum creatine kinase activity

The purpose of this study was to determine the effects of acupuncture on delayed onset muscle soreness (DOMS) produced by exercise. Baseline data were collected on 20 male subjects for intensity of muscle soreness and serum creatine kinase (CK) activity. All values were subsequently reassessed 24, 48 and 72 hours after exercise. The experimental group received acupuncture treatment while the control group received no treatment. Muscle soreness perception was significantly less (P < 0.05) at 72 hours in the acupuncture treated group compared to control group. However, the change in CK was not significantly different between groups. These results suggest that acupuncture is effective in decreasing muscle soreness but does not prevent CK release from muscle.

Trilinolein potentiates the pro-aggregating effect of phorbol-12-myristate 13-acetate in human polymorphonuclear leukocytes

Trilinolein, a triacylglycerol with linoleic acid as the only type of fatty acid residue in all three of the glycerol esterified positions, was recently reported to have an antiplatelet effect, mediated through stimulating nitric oxide and cyclic guanosine monophosphate (GMP) formation. In our study, trilinolein induced aggregation of human polymorphonuclear neutrophils (PMNs) and, pretreatment with 0.1 nM trilinolein enhanced phorbol-12-myristate 13-acetate (PMA) induced aggregation. Further investigation showed that trilinolein at concentrations ranging from 0.1 nM to 10 microM increased cyclic GMP formation after 10 min of incubation with PMNs. Pretreatment of trilinolein with 10 microM d-sphingosine, before being incubated with PMNs, attenuated the stimulatory effect of trilinolein on cyclic GMP formation, and pretreatment of 10 microM d-sphingosine also attenuated the aggregation induced by PMA and trilinolein. We conclude that trilinolein can induce the aggregation of human PMNs, and enhance the aggregation induced by PMA.

The mechanism of phosphorylation-inducible activation of the ETS-domain transcription factor Elk-1

Protein phosphorylation represents one of the major mechanisms for transcription factor activation. Here we demonstrate a molecular mechanism by which phosphorylation by mitogen-activated protein (MAP) kinases leads to changes in transcription factor activity. MAP kinases stimulate DNA binding and transcriptional activation mediated by the mammalian ETS-domain transcription factor Elk-1. Phosphorylation of the C-terminal transcriptional activation domain induces a conformational change in Elk-1, which accompanies the stimulation of DNA binding. C-terminal phosphorylation is coupled to activation of DNA binding by the N-terminal DNA-binding domain via an additional intermediary domain. Activation of DNA binding is mediated by an allosteric mechanism involving the key phosphoacceptor residues. Together, these results provide a molecular model for how phosphorylation induces changes in Elk-1 activity.

Correlations of serum lipids, uric acid, and albumin among mothers, offspring, and siblings in Taipei, Taiwan

The purpose of this study was to investigate the correlations of serum lipids, uric acid, and albumin, among mothers (n = 111), offspring (n = 208), and siblings (n = 57) in Taipei, Taiwan. Analytical items included serum triglyceride, serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, uric acid, and albumin. Statistical analysis was performed according to the SAS UNIVARIATE procedure; while regression coefficient, parent-offspring regressions, paired-comparison and heritability were estimated. These results show higher heritabilities of four types of serum lipids, uric acid and albumin between mothers and testers (bYX) or siblings (bZX) by parent-offspring regression analysis. Regression coefficients (bYX) of six characters were significantly different (p < 0.05-0.01). Regression coefficients (bZX) for total cholesterol, low-density lipoprotein cholesterol, uric acid, and albumin were significantly different (p < 0.05-0.01), showing the result of genetic control, because their heritabilities were very high at 0.75-1.0, 0.77-1.0, 0.96-1.0, and 0.48-0.82, respectively. This study disclosed that the serum lipids of children in Taipei, Taiwan were significantly correlated with that of parents, which may be attributed to the result of genetic control.

Targeting of p38 mitogen-activated protein kinases to MEF2 transcription factors

Mitogen-activated protein (MAP) kinase-mediated signalling to the nucleus is an important event in the conversion of extracellular signals into a cellular response. However, the existence of multiple MAP kinases which phosphorylate similar phosphoacceptor motifs poses a problem in maintaining substrate specificity and hence the correct biological response. Both the extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK) subfamilies of MAP kinases use a second specificity determinant and require docking to their transcription factor substrates to achieve maximal substrate activation. In this study, we demonstrate that among the different MAP kinases, the MADS-box transcription factors MEF2A and MEF2C are preferentially phosphorylated and activated by the p38 subfamily members p38alpha and p38beta2. The efficiency of phosphorylation in vitro and transcriptional activation in vivo of MEF2A and MEF2C by these p38 subtypes requires the presence of a kinase docking domain (D-domain). Furthermore, the D-domain from MEF2A is sufficient to confer p38 responsiveness on different transcription factors, and reciprocal effects are observed upon the introduction of alternative D-domains into MEF2A. These results therefore contribute to our understanding of signalling to MEF2 transcription factors and demonstrate that the requirement for substrate binding by MAP kinases is an important facet of three different subclasses of MAP kinases (ERK, JNK, and p38).

Estrogen attenuates over-expression of beta-amyloid precursor protein messager RNA in an animal model of focal ischemia

Cerebral ischemia is a risk factor for late onset Alzheimer's disease. Since estrogen replacement therapy benefits the outcome of cerebral stroke in post-menopausal women, we designed the present study to investigate the effects of estrogen on the expression of beta-amyloid precursor protein (APP) mRNA following focal ischemia in female rats. Female rats were ovariectomized (OVX) for two weeks. A single dose of 17 beta-estradiol (E2) (100 microgram/kg) was injected s.c. two hours before a unilateral middle cerebral artery (MCA) occlusion. Brain samples were harvested from ischemic core and penumbra of cortices at one hour and twenty-four hours following MCA occlusion. The expression of APP mRNA was assessed by RT-PCR. At one hour after MCA occlusion, OVX rats had a 67.9% (p<0.05) increase in APP mRNA in the penumbra. E2 treatment reduced this APP mRNA over-expression by 26.3% at that region. At twenty four hours following MCA occlusion, OVX rats had increases in APP mRNA of 52.9% and 57.0% (p<0.05) in the core and penumbra, respectively. E2 treatment reduced the APP mRNA over-expression by 61.0% and 48.6% (p<0.05) in these two regions, respectively. These effects appeared to reflect an interaction between hormonal environment and ischemia, since in the absence of MCA occlusion, there were no significant differences in APP mRNA expression among OVX, OVX-E2 treated and intact female rats. The present study demonstrates that estrogen may have an important role in reducing the over-expression of APP mRNA following focal ischemia.

Intramedullary versus extramedullary tibial alignment guides in total knee arthroplasty

The intramedullary alignment guide is superior to the extramedullary guide for preparation of the femur in total knee arthroplasty. However, there is controversy over which guide is more appropriate for the tibial sector. We retrospectively compared the accuracy of the intramedullary and extramedullary guides for tibial cutting in patients undergoing total knee arthroplasty. Total knee arthroplasty was performed in 100 knees (68 patients) during a 2-year period. The intramedullary rod was used for preparation of the femur in all cases. For the tibia, each guide system was used in 50 knees. The intramedullary rod was not used in tibias with extreme deformity where the rod could not pass at least two-thirds of the way through the medullary canal. Standing anteroposterior radiographs of the hip to the ankle were taken before surgery and 2 to 6 months postoperatively. The angle formed by the intersection of the tibial mechanical axis and the undersurface of the tibial component (tibial component angle) was measured to check the accuracy of the tibial alignment system. We found no significant differences in the mechanical axis, tibiofemoral alignment, or the tibial component angle between the two groups. The proximal tibial cuts were within 2 degrees of the ideal (90 degrees) in 84% of knees treated with the intramedullary guide, and in 82% of those with the extramedullary guide (p > 0.1). These findings suggest that both guide systems can yield satisfactory alignment. If the tibia is not badly deformed, the intramedullary rod can produce tibial cuts as accurately as the extramedullary system.

Pheochromocytoma complicated with cardiomyopathy after delivery--a case report and literature review

Pheochromocytoma in pregnancy is very rare but it is associated with very high maternal and fetal mortality. Therefore, it is important to include pheochromocytoma in the differential diagnosis of hypertension associated with pregnancy. It is difficult to make a diagnosis of pheochromocytoma in pregnancy before delivery. The characteristic symptoms of pheochromocytoma could be initiated during delivery because the process of delivery, general anesthesia, fetal movement, induce acute surge of catecholamine release, which could also induce cardiomyopathy. Early diagnosis and intensive care can affect the prognosis of cardiomyopathy induced by pheochromocytoma. Proper management with alpha-blockade, beta-blockade and angiotension converting enzyme inhibitor could acutely reverse the course of cardiomyopathy.

Neural network computer program to determine photorefractive keratectomy nomograms

PURPOSE

To evaluate a commercially available neural network program for calculation of photorefractive keratectomy treatment nomograms.

SETTING

University referral refractive surgery clinic.

METHODS

PRK/LASIK Brain, a commercial neural network computer program, was trained using the demographics, preoperative clinical data, surgical parameters, and 1 year postoperative clinical data of 44 patients treated with a Summit Technology excimer laser using a 5.0 mm optical zone. The neural-network derived nomogram was compared with the standard treatment nomogram for each patient. The relative contribution of age, sex, keratometry, and intraocular pressure (IOP) to the predicted nomograms was also assessed.

RESULTS

Nomograms produced by the neural network were qualitatively similar to the standard nomogram. The sequence of data entry during training affected the network's predictions. Entry ordered by outcome (as opposed to entry by chronological order) yielded a nomogram that was more consistent with the standard nomogram. However, both outcome- and chronologically ordered network-derived nomograms diverged from the standard nomogram in individual patients, including a subset for whom use of the standard nomogram yielded desired refractive results (within 0.25 diopter of emmetropia). Further analysis of the neural-network-derived nomograms revealed marked sensitivity to sex, age, keratometry readings, and IOP.

CONCLUSIONS

Neural networks offer a potential means of individualizing treatment nomograms, to account for patient demographics, preoperative examination, surgeon style, and equipment bias. However, a data set of 44 patients was not sufficient to train the PRK/LASIK Brain network to accurately predict treatment parameters in individual cases in the training set. A larger training set or a different learning algorithm may be required to improve the neural network's performance.

In vivo assay for hepatitis C viral serine protease activity using a secreted protein

Hepatitis C virus (HCV) is a major pathogen of community-acquired and post-transfusional non-A, non-B hepatitis. Since an in vitro replication system is not available, it is crucial to develop an efficient and sensitive assay system for screening inhibitors of HCV. The fact that the activity of HCV NS3 protease is responsible for the maturation of the nonstructural proteins and viral replication, suggests that NS3 protease is a suitable target for anti-HCV drug development. To devise an assay system in cell culture, we constructed NS3/4A-SEAP (secreted alkaline phosphatase) chimeric gene, in which the SEAP gene was fused in-frame to downstream of NS4A/4B cleavage site. In this system, the SEAP would be secreted into the extracellular media depending on the cleavage activity of the NS3 protease. Our results demonstrate that the NS3/4A-SEAP expression vector encoding wild type NS3 protease, but not mutant NS3 protease, could produce high SEAP activity in the media of both transfected cells and stable expression cell lines. Since the activity of SEAP in the culture media can be monitored quantitatively and continuously by the chemiluminescent method, this assay system will be useful for screening potential inhibitors of HCV protease.

Hepatitis C virus core from two different genotypes has an oncogenic potential but is not sufficient for transforming primary rat embryo fibroblasts in cooperation with the H-ras oncogene

Persistent infection with hepatitis C virus (HCV) is associated with the development of liver cirrhosis and hepatocellular carcinoma. To examine the oncogenic potential of the HCV core gene product, primary rat embryo fibroblasts (REFs) were transfected with the core gene in the presence or absence of the H-ras oncogene. In contrast to a previous report (R. B. Ray, L. M. Lagging, K. Meyer, and R. Ray, J. Virol. 70:4438-4443, 1996), HCV core proteins from two different genotypes (type 1a and type 1b) were not found to transform REFs to tumorigenic phenotype in cooperation with the H-ras oncogene, although the core protein was successfully expressed 20 days after transfection. In addition, REFs transfected with E1A- but not core-expressing plasmid showed the phenotype of immortalized cells when selected with G418. The biological activity was confirmed by observing the transcription activation from two viral promoters, Rous sarcoma virus long terminal repeat and simian virus 40 promoter, which are known to be activated by the core protein from HCV-1 isolate. In contrast to the result with primary cells, the Rat-1 cell line, stably expressing HCV core protein, exhibited focus formation, anchorage-independent growth, and tumor formation in nude mice. HCV core protein was able to induce the transformation of Rat-1 cells with various efficiencies depending on the expression level of the core protein. These results indicate that HCV core protein has an oncogenic potential to transform the Rat-1 cell line but is not sufficient to either immortalize primary REFs by itself or transform primary cells in conjunction with the H-ras oncogene.

Differential targeting of MAP kinases to the ETS-domain transcription factor Elk-1

The activation of MAP kinase (MAPK) signal transduction pathways results in the phosphorylation of transcription factors by the terminal kinases in these cascades. Different pathways are activated by mitogenic and stress stimuli, which lead to the activation of distinct groups of target proteins. The ETS-domain transcription factor Elk-1 is a substrate for three distinct classes of MAPKs. Elk-1 contains a targeting domain, the D-domain, which is distinct from the phosphoacceptor motifs and is required for efficient phosphorylation and activation by the ERK MAPKs. In this study, we demonstrate that members of the JNK subfamily of MAPKs are also targeted to Elk-1 by this domain. Targeting via this domain is essential for the efficient and rapid phosphorylation and activation of Elk-1 both in vitro and in vivo. The ERK and JNK MAPKs use overlapping yet distinct determinants in the D-domain for targeting to Elk-1. In contrast, members of the p38 subfamily of MAPKs are not targeted to Elk-1 via this domain. Our data therefore demonstrate that different classes of MAPKs exhibit differential requirements for targeting to Elk-1.

The Elk-1 ETS-domain transcription factor contains a mitogen-activated protein kinase targeting motif

The phosphorylation of transcription factors by mitogen-activated protein kinases (MAP) is a pivotal event in the cellular response to the activation of MAP kinase signal transduction pathways. Mitogenic and stress stimuli activate different pathways and lead to the activation of distinct groups of target proteins. Elk-1 is targeted by three distinct MAP kinase pathways. In this study, we demonstrate that the MAP kinase ERK2 is targeted to Elk-1 by a domain which is distinct from, and located N-terminally to, its phosphoacceptor motifs. Targeting via this domain is essential for the efficient and rapid phosphorylation of Elk-1 in vitro and full and rapid activation in vivo. Specific residues involved in ERK targeting have been identified. Our data indicate that the targeting of different classes of MAP kinases to their nuclear substrates may be a common mechanism to increase the specificity and efficiency of this signal transduction pathway.

Angiographic study of moyamoya disease and histological study in the external carotid artery system

A total of 13 cases of Moyamoya disease were verified by internal and external carotid artery angiography. The biopsy samples were taken from the superficial temporal arteries and middle meningeal arteries in 12 and six cases, respectively. Angiographical and histological studies revealed that both of the internal and external carotid system could be involved in Moyamoya disease. Our studies demonstrated that Moyamoya disease was a type of vascular disease not only confined to the cerebral vessels. We recommend angiography of external carotid system and extracranial segment of internal carotid artery while performing three vascular angiography. Whether superficial temporal artery has been involved in angiography can be used as an indication of indirect cerebrovascular bypass.

Comparison of various expression plasmids for the induction of immune response by DNA immunization

Intramuscular injection of plasmid DNA is an efficient method to introduce a foreign gene into a live animal. We investigated several factors affecting the gene transfer efficiency and the following immune response by intramuscular injection of plasmid DNA. When the strength of several highly efficient viral promoters was compared in muscle by using the chloramphenicol acetyltransferase (CAT) gene as an indicator, cytomegalovirus (CMV) immediate early promoter was found to be stronger than any other viral promoters including Rous sarcoma virus (RSV), murine leukemia virus (SL3-3) and simian virus 40 (SV40) early promoters. Inclusion of adenovirus tripartite leader (TPL) sequences and a synthetic intron in the 5' untranslated region of mRNA moderately stimulated the CAT expression. On the other hand, the expression of encephalomyocarditis virus (EMCV) VP1 gene was greatly enhanced by the TPL sequences and an intron. The level of humoral immune response by intramuscular injection of various VP1 expression plasmids was compared. The seroconversion rate was highly dependent on the strength of the expression vector. However, the ratio of IgG1 and IgG2a immune response was not significantly variable depending on the strength of the expression vector. Also, the efficiency of the sindbis virus-based DNA vector was examined for the gene expression and immune response. Although a high level of CAT expression was obtained in muscle by using this system, VP1 was not produced as much as the conventional expression vectors. Furthermore, little humoral immune response was elicited by intramuscular injection of VP1-expressing sindbis vector, suggesting that this system was not superior to the conventional vector for DNA immunization.

Role of p38 and JNK mitogen-activated protein kinases in the activation of ternary complex factors

The transcription factors Elk-1 and SAP-1 bind together with serum response factor to the serum response element present in the c-fos promoter and mediate increased gene expression. The ERK, JNK, and p38 groups of mitogen-activated protein (MAP) kinases phosphorylate and activate Elk-1 in response to a variety of extracellular stimuli. In contrast, SAP-1 is activated by ERK and p38 MAP kinases but not by JNK. The proinflammatory cytokine interleukin-1 (IL-1) activates JNK and p38 MAP kinases and induces the transcriptional activity of Elk-1 and SAP-1. These effects of IL-1 appear to be mediated by Rho family GTPases. To examine the relative roles of the JNK and p38 MAP kinase pathways, we examined the effects of IL-1 on CHO and NIH 3T3 cells. Studies of NIH 3T3 cells demonstrated that both the JNK and p38 MAP kinases are required for IL-1-stimulated Elk-1 transcriptional activity, while only p38 MAP kinase contributes to IL-1-induced activation of SAP-1. In contrast, studies of CHO cells demonstrated that JNK (but not the p38 MAP kinase) is required for IL-1-stimulated Elk-1-dependent gene expression and that neither JNK nor p38 MAP kinase is required for IL-1 signaling to SAP-1. We conclude that (i) distinct MAP kinase signal transduction pathways mediate IL-1 signaling to ternary complex transcription factors (TCFs) in different cell types and (ii) individual TCFs show different responses to the JNK and p38 signaling pathways. The differential utilization of TCF proteins and MAP kinase signaling pathways represents a potential mechanism for the determination of cell-type-specific responses to extracellular stimuli.

Clustering of GABAA receptors by rapsyn/43kD protein in vitro

Rapsyn, a 43-kDa protein on the cytoplasmic face of the postsynaptic membrane, is essential for clustering acetylcholine receptors (AChR) at the neuromuscular junction. When transfected into nonmuscle cells (QT-6), rapsyn forms discrete membrane domains and can cluster AChR into these same domains. Here we examined whether rapsyn can cluster other ion channels as well. When expressed in QT-6 cells, the GABAA receptor (human alpha 1, beta 1, and gamma 2 subunits) and the skeletal muscle sodium channel were each diffusely scattered across the cell surface. Rapsyn, when co-expressed, clustered the GABAA receptor as effectively as it clustered AChR in previous studies. Rapsyn did not cluster co-transfected sodium channel, confirming that it does not cluster ion channels indiscriminately. Rapsyn mRNA was detected at low levels in the brain by polymerase chain reaction amplification of reverse-transcribed RNA, raising the possibility of a broader role for rapsyn.

Valgus osteotomy for congenital coxa vara

Congenital coxa vara is a rare disease which can result in a significant disability if untreated or improperly treated. In this retrospective review of eight patients (12 hips) with congenital coxa vara, there were five boys and three girls. Four patients had bilateral involvement and four had unilateral involvement. At the time of surgery, the average age was 7.9 years. All patients underwent valgus intertrochanteric osteotomy with wires or blade-plates for fixation. The mean Hilgenreiner-epiphyseal angle was 75 degrees before surgery and improved to 25 degrees after surgery. The mean neck-shaft angle improved from 95 degrees to 137 degrees immediately after the osteotomies and was 125 degrees at the final follow-up. At a minimum two year follow-up only three hips in three patients maintained more than 80% correction. These three patients all had developmental coxa vara. The acetabular depth improved significantly in the patients with developmental coxa vara, especially in two patients (three hips) who underwent surgery before 6 years of age. Closure of physeal plates was found in three patients (five hips) before surgery and occurred in two patients (two hips) after surgery. After surgery, only two patients had persistent soreness. One patient walked with a limp, and the other, with multiple epiphyseal dysplasia had significant leg length discrepancy. Our results show that valgus osteotomy can correct varus deformities of the proximal femur and improve function. If performed early, it can also prevent the development of hip dysplasia in patients with developmental coxa vara. However, the response of acetabular development was variable in patients with coxa vara due to skeletal dysplasia, despite valgus osteotomy.

Cloning and characterization of rat Ku70: involvement of Ku autoantigen in the heat-shock response

To study the role of the Ku autoantigen in the heat-shock response, we have cloned the 70-kDa subunit (the DNA-binding component of Ku) from a rat cDNA library. The deduced amino acid sequence of rat Ku70 bears extensive homology with the human and murine counterpart (83 and 97% identity, respectively). Overexpression of Ku70 in rat fibroblasts results in the specific repression of hsp-70 upon heat shock. The inhibition of induction of hsp-70 was greatest in cells expressing the highest level of Ku70. Induction of other heat-shock proteins besides hsp-70 by hyperthermia appears normal, as does the activation of the heat-shock transcription factor, HSF-1. It is likely that other factors besides HSF-1 are involved in controlling heat-shock gene transcription. While the formation of the Ku70 and Ku80 complex is important for repair of DNA double-strand breaks our data suggest that the 70-kDa subunit of Ku plays a role in regulating hsp-70 expression.

Modulation of thermal induction of hsp70 expression by Ku autoantigen or its individual subunits

Previously, we proposed a dual control mechanism for the regulation of the heat shock response in mammalian cells: a positive control mediated by the heat shock transcription factor HSF1 and a negative control mediated by the constitutive heat shock element-binding factor (CHBF). To study the physiological role of CHBF in the regulation of heat shock response, we purified CHBF to apparent homogeneity and showed it to be identical to the Ku autoantigen, a heterodimer consisting of 70-kDa (Ku-70) and 86-kDa (Ku-80) polypeptides. To study further the functional significance of Ku/CHBF in the cellular response to heat shock, we established rodent cell lines that stably and constitutively overexpressed one or both subunits of the human Ku protein, and examined the thermal induction of hsp70 and other heat shock proteins in these Ku-overexpressing ing cells. We show that expression of the human Ku-70 and Ku-80 subunits jointly or of the Ku-70 subunit alone specifically inhibits heat-induced hsp70 expression. Conversely, expression of human Ku-80 alone does not have this effect. Thermal induction of other heat shock proteins in all of the Ku-overexpressing cell lines appears not to be significantly affected, nor is the state of phosphorylation or the DNA-binding ability of HSF1 affected. These findings support a model in which hsp70 expression is controlled by a second regulatory factor in addition to the positive activation of HSF1. The Ku protein, specifically the Ku-70 subunit, is involved in the regulation of hsp70 gene expression.

Clinicopathologic study on clear cell hepatocellular carcinoma

In order to study the clinicopathologic characteristics of the clear cell variant of hepatocellular carcinoma (HCC), 215 consecutive cases measuring less than 5 cm in diameter were reviewed. The cases were divided into clear cell HCC (20 cases); focal clear cell HCC (77 cases); and non-clear cell HCC (118 cases). Clinical and pathological findings were compared among these groups. Clear cell HCC was moderately differentiated in 80% of cases and the incidence was not related to tumor size. The male to female ratio was 2.3:1, lower than the 6.9:1 of non-clear cell HCC. The association rate with liver cirrhosis was 90%, higher than the 59.3% of non-clear cell HCC. Three- and five-year survival rates, and no recurrence time were 54.5%, 33.3%, and 564 days, respectively, lower than the findings of 74.3%, 46.1%, and 770 days for non-clear cell HCC. But there is no significant difference in prognosis between both groups. Ultrastructurally, clear cells showed abundant glycogen storage and a variable degree of fat vacuoles, with a marked reduction of the number and size of organelles in the 8 cases examined. Non-clear cells of focal clear cell and non-clear cell HCC showed a moderate degree of glycogen storage in 85.7% and 28.6% of the seven cases examined from each group, with significant difference. It was concluded that clear cell HCC occurs mostly in the moderately differentiated form and is characterized by high female prevalence, high rate of association with liver cirrhosis, and has no significant difference in prognosis compared with non-clear cell HCC.

Interleukin-6 concentrations in umbilical cord plasma are elevated in neonates with white matter lesions associated with periventricular leukomalacia

OBJECTIVE

Periventricular leukomalacia, a common brain white matter lesion in preterm neonates, is a major risk factor for cerebral palsy. Recently, cytokines (i.e., tumor necrosis factor and interleukin-1(beta)) have been implicated as mediators for the development of periventricular leukomalacia. The purpose of this study was to examine the relationship between umbilical cord plasma levels of tumor necrosis factor-alpha, interleukin-1(beta), interleukin-6, and interleukin-1 receptor antagonist and the occurrence of periventricular leukomalacia in preterm neonates.

STUDY DESIGN

Umbilical cord blood was collected from 172 consecutive preterm births (25 to 36 weeks). Periventricular leukomalacia-associated lesions were diagnosed by brain ultrasonography within the first 3 days of life. Tumor necrosis factor-alpha, interleukin-1(beta) interleukin-6, and interleukin-1 receptor antagonist were measured by sensitive and specific enzyme-linked immunoassay methods. Umbilical cord arterial pH was measured at birth. Statistical analysis was performed with multiple logistic regression and receiver operating characteristic curve analysis.

RESULTS

Periventricular leukomalacia-associated lesions were present in 14.5% (25/172) of infants. Plasma concentrations of interleukin-6 but not of tumor necrosis factor-alpha, interleukin-1(beta), and interleukin-1 receptor antagonist were significantly higher in neonates with periventricular leukomalacia-associated lesions than in those without these lesions (median 718, range < 226 to 32,000 pg/ml vs median < 226, range < 226 to 43,670 pg/ml; p < 0.0001). An interleukin-6 value > or = 400 pg/ml had a sensitivity of 72% (18/25) and a specificity of 74% (108/147) in the identification of periventricular leukomalacia-associated lesions. Multivariate analysis showed that umbilical cord interleukin-6 was an independent risk factor for periventricular leukomalacia (odds ratio 6.2, p < 0.002) after correction for known confounding variables (i.e., gestational age at birth, umbilical artery pH, chorioamnionitis).

CONCLUSIONS

Interleukin-6 concentrations in umbilical cord plasma are elevated in neonates with periventricular leukomalacia-associated lesions. Our data support the hypothesis that periventricular leukomalacia may be the result of cytokine-mediated brain injury.

Treatment of posttraumatic chronic high-flow priapisms by superselective embolization of cavernous artery with autologous clot

Two cases of high-flow priapism that occurred after blunt perineal trauma and lasted for 35 days (case 1) and 40 days (case 2) were successfully treated by embolization of the lacerated cavernous arteries with autologous clots. Cavernous arterial blushes were demonstrated on selective internal pudendal arteriograms in both cases. Case 1 with left cavernous arterial laceration restored 80% of premorbid erectile function with successful intercourse 4 months after superselective embolization. In case 2 with bilateral cavernous arterial lacerations, premorbid erectile function was fully resumed 2 months after bilateral embolization of the cavernous arteries at intervals of 15 days. None developed local or systemic complications.

Maternal blood C-reactive protein, white blood cell count, and temperature in preterm labor: a comparison with amniotic fluid white blood cell count

OBJECTIVE

To compare the diagnostic and prognostic performance of maternal blood C-reactive protein, white blood cell count (WBC), and temperature with that of amniotic fluid (AF) WBC in preterm labor.

METHODS

One hundred two women with preterm labor and intact membranes were studied. Maternal blood was collected to measure C-reactive protein concentration and WBC, and maternal temperature was also measured. Amniotic fluid obtained by amniocentesis was cultured and WBC determined. Receiver operating characteristic curve, logistic regression, and survival techniques were used for analysis.

RESULTS

Patients with acute histologic chorioamnionitis had significantly higher median C-reactive protein concentration, WBC, temperature, and AF WBC than patients without this lesion (P < .05). Receiver operating characteristic curve and survival analysis demonstrated that an elevated C-reactive protein, WBC, or AF WBC was strongly associated with the likelihood of histologic chorioamnionitis, shorter interval to delivery, clinical chorioamnionitis, and neonatal morbidity (P < .05 for each). Of all the tests, AF WBC was the best independent predictor of a positive AF culture (odds ratio [OR] 16.8), interval to delivery (hazard ratio 5.7), clinical chorioamnionitis (OR 15.2), neonatal sepsis (OR 16.8), and significant neonatal complications (OR 7.4), after other confounding variables were adjusted (P < .05 for each).

CONCLUSION

An elevated C-reactive protein, WBC, or AF WBC identified patients with intrauterine infection and adverse perinatal outcomes. Amniotic fluid WBC was a better independent predictor of these outcomes than C-reactive protein, WBC, or temperature.

Inhibitors of signalling identify differential control processes responsible for selective effects of insulin on the expression of phosphoenolpyruvate carboxykinase and gene 33 in rat H4 hepatoma cells

Gene 33 and phosphoenolpyruvate carboxykinase (PEPCK) present excellent model systems for the analysis of the differential control of hepatic gene expression by the insulin-regulated signal-transduction pathway(s). We have analysed the importance of specific components in the insulin-regulated transduction pathway(s) towards enhanced gene expression (gene 33) and inhibited gene expression (PEPCK) by examination of the influence of selective inhibitors. Rapamycin, which inhibits the 70 kDa S6 kinase (p70rsk) does not influence the actions of insulin on gene 33 or PEPCK; thus the kinase p70rsk appears to play no direct role in the regulation of expression of these two hepatic genes. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, differentiates between processes involved in insulin regulation of gene 33 and PEPCK mRNA expression. Although the actions of insulin on gene 33 expression are abolished by wortmannin, the actions of insulin on PEPCK expression are insensitive to wortmannin. The existence of wortmannin-sensitive and rapamycin/wortmannin-insensitive pathways for transducing insulin signals to factors controlling gene expression, and the differential actions on specific genes, presents an initial step towards deciphering the linkage between signalling components and selective control of gene expression.

Aggretin, a novel platelet-aggregation inducer from snake (Calloselasma rhodostoma) venom, activates phospholipase C by acting as a glycoprotein Ia/IIa agonist

A potent platelet aggregation inducer, aggretin, was purified from Malayan-pit-viper (Calloselasma rhodostoma) venom by ionic-exchange chromatography, gel-filtration chromatography and HPLC. It is a heterodimeric protein (29 kDa) devoid of esterase, phospholipase A and thrombin-like activity. Aggretin (> 5 nM) elicited platelet aggregation with a lag period in both human platelet-rich plasma and washed platelet suspension. EDTA (5 mM), prostaglandin E1 (1 microM) and 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester ('TMB-8'; 100 microM) abolished its aggregating activity, indicating that exogenous bivalent cations and intracellular Ca2+ mobilization are essential for aggretin-induced platelet aggregation. Neomycin (4 mM) and mepacrine (50 microM) completely inhibited aggretin (33 nM)-induced aggregation; however, creatine phosphate/creatine phosphokinase (5 mM, 5 units/ml) and indomethacin (50 microM) did not significantly affect its aggregating activity. Aggretin caused a significant increase of [3H]InsP formation in [3H]Ins-loaded platelets, intracellular Ca2+ mobilization and thromboxane B2 formation. Neomycin, a phospholipase C inhibitor, completely inhibited both the increase of [3H]InsP and intracellular Ca2+ mobilization of platelets stimulated by aggretin. A monoclonal antibody (6F1) directed against glycoprotein Ia/IIa inhibited platelet shape change and aggregation induced by aggretin. 125I-aggretin bound to platelets with a high affinity (Kd = 4.0 +/- 1.1 nM), and the number of binding sites was estimated to be 2119 +/- 203 per platelet. It is concluded that aggretin may act as a glycoprotein Ia/IIa agonist to elicit platelet aggregation through the activation of endogenous phospholipase C, leading to hydrolysis of phosphoinositides and subsequent intracellular Ca2+ mobilization.

A constitutive heat shock element-binding factor is immunologically identical to the Ku autoantigen

Analysis of the heat shock element (HSE)-binding proteins in extracts of rodent cells, during heat shock and their post-heat shock recovery, indicates that the regulation of heat shock response involves a constitutive HSE-binding factor (CHBF), in addition to the heat-inducible heat shock factor HSF1. We purified the CHBF to apparent homogeneity from HeLa cells using column chromatographic techniques including an HSE oligonucleotide affinity column. The purified CHBF consists of two polypeptides with apparent molecular masses of 70 and 86 kDa. Immunoblot and gel mobility shift analysis verify that CHBF is identical or closely related to the Ku autoantigen. The DNA binding characteristics of CHBF to double-stranded or single-stranded DNA are similar to that of Ku autoantigen. In gel mobility shift analysis using purified CHBF and recombinant human HSF1, CHBF competes with HSF1 for the binding of DNA sequences containing HSEs in vitro. Furthermore, when Rat-1 cells were co-transfected with human Ku expression vectors and the hsp70-promoter-driven luciferase reporter gene, thermal induction of luciferase is significantly suppressed relative to cells transfected with only the hsp70-luciferase construct. These data suggest a role of CHBF (or Ku protein) in the regulation of heat response in vivo.

Suppression of heat-induced hsp70 expression by the 70-kDa subunit of the human Ku autoantigen

Expression of the 70-kDa polypeptide of human Ku autoantigen in rat cells is shown to suppress specifically the induction of hsp70 upon heat shock. Thermal induction of other heat shock proteins is not significantly affected, nor is the state of phosphorylation or the DNA-binding ability of the heat shock transcription factor HSF1. These findings support a model in which hsp70 gene expression is controlled by a second regulatory factor in addition to the positive activator HSF1. The Ku autoantigen, or a protein closely related to it, is likely to be involved in the regulation of hsp70 expression.

Highly specific oxidative cross-linking of proteins mediated by a nickel-peptide complex

The Ni(II) complex of the tripeptide NH2-Gly-Gly-His-COOH is shown to mediate efficient protein-protein cross-linking in the presence of oxidants such as oxone and monoperoxyphthalic acid. Only proteins that associate specifically in solution are cross-linked under these conditions. Preliminary probes of the mechanism of the reaction suggest that the active intermediate may be a high-valent metal complex that attacks aromatic amino acids.

An abduction-traction frame for the treatment of intertrochanteric fracture of femur

We present a detailed outline of treatment of intertrochanteric fractures of femur with a new technique on the basis of principles of combined traditional chinese and western medicine. We use pins and an outer fixation frame, which keeps the injured limb in abduction and under traction and at the same time allows for functional exercise of all the joints in the extremity. The procedure is discussed and compared with other different techniques.

Acupuncture protection against experimental hyperbilirubinemia and cholangitis in rats

Effects of acupuncture on experimental hyperbilirubinemia and cholangitis were studied in male rats (n = 33). The experimental group were treated with acupuncture, 18, 12 and 6 hr prior to and 6, 12 and 18 hr after oral administration of alpha-napthylisothiocyanate (ANIT, 100 mg per Kg). Rats were sacrificed 48 hours after challenge. Serum and liver samples were taken for biochemical and histological analysis, respectively. Results of this study revealed that rats treated with ANIT exhibited elevations in bilirubin, SGOT and SGPT as well as cholangitis. In rats receiving acupuncture and ANIT, biochemical and morphological parameters of liver injury were significantly reduced. Acupuncture therapy may be able to prevent ANIT-induced hyperbilirubinemia and cholangitis.

[Observation of electroencephalogram spectrum changes over one year of Qigong training]

Using spectrum analysis method, the electroencephalogram (EEG) changes of the students who first learned Zhanzhuang Qigong in comparing with the students who did not practice at all were observed, over a period of one year. The results showed that the spectrum of EEG did not change significantly after half year training, but one year later, the alpha index of right frontal and right temporal regions decreased significantly (P < 0.05), and the beta index of right frontal and right temporal regions decreased significantly (P < 0.05). It was indicated that there was a higher tendency of EEG synchyonization, the brain activity changed from "active" to "harmonious" and "calm". It was a gradually adjusting process.

A diallel analysis of heterosis in elite hybrid rice based on RFLPs and microsatellites

Hybrid rice has contributed significantly to the dramatic increase of rice production in the world. Despite this, little attention has been given to studying the genetic basis of heterosis in rice. In this paper, we report a diallel analysis of heterosis using two classes of molecular markers: restriction fragment length polymorphisms, (RFLPs) and microsatellites. Eight lines, which represent a significant portion of hybrid rice germ plasm, were crossed in all possible pairs, and the F1s were evaluated for yield and yield component traits in a replicated field trial. The parental lines were surveyed for polymorphisms with 117 RFLP probes and ten microsatellites, resulting in a total of 76 polymorphic markers well-spaced in the rice RFLP map. The results indicated that high level heterosis is common among these crosses: more than 100% midparent and 40% better-parent heterosis were observed in many F1s, including some crosses between maintainer lines. Heterosis was found to be much higher for yield than for yield component traits, which fits a multiplicative model almost perfectly. Between 16 and 30 marker loci (positive markers) detected highly significant effects on yield or its component traits. Heterozygosity was significantly correlated with several attributes of performance and heterosis. Correlations based on positive markers (specific heterozygosity) were large for midparent heterosis of yield and seeds/panicle and also for F1 kernel weight. These large correlations may have practical utility for predicting heterosis.