C-terminal-truncated HBV X promotes hepato-oncogenesis through inhibition of tumor-suppressive β-catenin/BAMBI signaling

C-terminal-truncated hepatitis B virus (HBV) X (HBx) (ctHBX) is frequently detected in hepatocellular carcinoma (HCC) through HBV integration into the host genome. However, the molecular mechanisms underlying ctHBx-associated oncogenic signaling have not yet been clarified. To elucidate the biological role of ctHBx in hepato-oncogenesis, we functionally analyzed ctHBx-mediated regulation of the activin membrane-bound inhibitor bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) through transforming growth factor-β (TGF-β) or β-catenin (CTNNB1) in HCC cells and in an animal model, and we compared its role to that of the full-length HBx protein. Ectopic ctHBx expression generated more colonies in anchorage-dependent and -independent growth assays than did HBx expression alone. ctHBx downregulated BAMBI to a greater degree than did HBx in HCC cells. HBx activated the Wnt/β-catenin pathway, which positively regulated the BAMBI expression through T-cell factor 1 signaling, whereas ctHBx negatively regulated the Wnt/β-catenin pathway. BAMBI downregulated the β-catenin and TGF-β1 signaling pathways. TGF-β1 positively regulated BAMBI expression thorough Smad3 signaling. Furthermore, knockdown of BAMBI was more tumorigenic in HCC cells. Therefore, downregulation of both β-catenin and TGF-β1 signaling by BAMBI might contribute to tumor suppression in mice xenotransplanted with HepG2 or SH-J1 cells. Taken together, ctHBx may have a more oncogenic role than HBx through its inhibition of tumor-suppressive β-catenin/BAMBI signaling.

[Clinical effect of compound internal fixations in treating extreme distal radial fractures]

Objective: To investigate the clinical character and treating strategy of extreme distal radial fractures. Methods: From June 2012 to May 2014, 12 patients who suffered from extreme distal radial fractures were treated in Department of Orthopedics, Tongji Hospital, Tongji University. According to AO/OTA classification, there were 4 cases of type 23B1, 3 cases of 23B2, 3 cases of 23C1 and 2 cases of 23C3.When classified by morphological features, there were 4 of simple styloid process fracture, 3 of simple extreme distal radial fracture without articular surface involved, 3 of styloid process fracture combined with distal radial articular fracture, and 2 of articular surface splintered or collapse fracture. According to the fracture features that radiographic exams showed, different surgical paths and fixation methods were chosen in order to protect soft tissues to the best advantage. To those patients with simple styloid process fracture, screw alone, Kirschner-wire or styloid plate were used for fixation. To the other types of fracture, open reduction and compound internal fixation with low-notch volar plate, dorsal or volar mini-plate, screw or Kirschner-wire was applied to ensure the stability of fixation, and maximally protect soft tissues like tendons, ligaments and neurovascular bundles, counting on the "stuffing-squeezing" effects after reduction or reconstruction of the articular surface. Situation of the wound and soft tissue were mainly checked in the first 2 weeks, and in the 3rd month post-operatively, fracture reduction and internal fixation were evaluated by radiographic methods like X-ray and CT scan. When 12 months post-operatively, not only radiographic follow-up such as fracture reduction, internal fixation and osteoarthritis were taken, but also some other evaluation, such as pain of wrist, rotation range of forearm, grip strength, and function of wrist according to DASH scores. Results: All of the 12 cases were followed up for at least 1 year. The wound healed well in all cases 2 weeks post-operatively, and no soft tissue infections, necrosis or neurovascular complications occurred. All fractures healed and no loss of reduction occurred 3 months post-operatively. Internal fixations were at good condition except in 2 cases, whose Kirschner-wire had been removed 2.5 and 2.8 months after the operation due to loosening and partly backing out on dorsal side. When followed up at 12 months post-operatively, one from these 2 patients suffered from a mild pain of wrist, and grip strength together with the function of the affected wrist dramatic declined when compared to the unaffected side. With the help of radiograph, local collapse on the articular surface was found, which meant to be traumatic arthritis. There were no pain in the rest 11 cases, and flexion-extension range of the wrist, rotation range of forearm and grip strength of the affected side recovered to over 80% of the unaffected side, with a DASH score was from 7 to 15 points(average 11.9 points)below 15 points. Conclusions: Traditional volar plates can not be used for extreme distal radial fractures. It may be an effective way to treat extreme distal radial fractures with compound internal fixation on the basis of morphological feature of fractures and the situation of soft tissue because of vivid of the fixation, reducing damage of soft tissue and early functional training.

Disruption of a regulatory loop between DUSP1 and p53 contributes to hepatocellular carcinoma development and progression

BACKGROUND & AIMS

Altered expression of dual specificity phosphatase 1 (DUSP1) is common in tumors including hepatocellular carcinoma (HCC), and is predictive of tumor progression and poor prognosis. However, the tumor suppressive role of DUSP1 has yet to be clearly elucidated.

METHODS

The molecular mechanisms of tumor suppression that were investigated were induction of apoptosis, cell cycle inhibition, and regulation of p53. Additionally, the antitumor effect of DUSP1 was assessed using a mouse model. Associated signaling pathways in HCC cells and tissues were examined.

RESULTS

Downregulation of DUSP1 expression was significantly correlated with poor differentiation (p<0.001) and advanced HCC stage (p=0.023). DUSP1 expression resulted in HCC suppression and longer survival (p=0.0002) in a xenoplant mice model. DUSP1 inhibited p38 MAPK phosphorylation and subsequently suppressed HSP27 activation, resulting in enhanced p53 phosphorylation at sites S15, S20, and S46 in HCC cells. Enhanced p53 activation induced the expression of target genes p21 and p27, which are linked to cell cycle arrest and apoptosis. Thus, DUSP1 was potentially linked to p53 activation via the p38 MAPK/HSP27 pathway. Wild-type but not mutant p53 transcriptionally upregulated DUSP1 via its DNA-binding domain. DUSP1 and p53 might collaborate to suppress tumors in hepatocarcinogenesis via a positive regulatory loop.

CONCLUSIONS

Our results revealed that disruption of a positive regulatory loop between DUSP1 and p53 promoted HCC development and progression, providing a rationale for a therapeutic agent that restores DUSP1 in HCC.

Isolation of EpCAM(+)/CD133 (-) hepatic progenitor cells

Progenitor cell-derived hepatocytes are critical for hepatocyte replenishment. Therefore, we established a line of human hepatic progenitor (HNK1) cells and determined their biological characteristics for experimental and therapeutic applications. HNK1 cells, isolated from human noncirrhotic liver samples with septal fibrosis, showed high expression of the hepatic progenitor cell (HPC) markers EpCAM, CK7, CK19, alpha-fetoprotein (AFP), CD90 (Thy1), and EFNA1. Expression of CD133 was very low. Ductular reactions at the periphery of cirrhotic nodules were immunohistochemically positive for these HPC markers, including EFNA1. Sodium butyrate, a differentiation inducer, induced hepatocyte-like morphological changes in HNK1 cells. It resulted in down-regulation of the hepatic progenitor cell markers EpCAM, CK7, CK19, AFP, and EFNA1 and up-regulation of mature hepatocyte markers, including albumin, CK8, and CK18. Furthermore, sodium butyrate treatment and a serial passage of HNK1 cells resulted in enhanced albumin secretion, ureagenesis, and CYP enzyme activity, all of which are indicators of differentiation in hepatocytes. However, HNK1 cells at passage 50 did not exhibit anchorage-independent growth capability and caused no tumors in immunodeficient mice, suggesting that they had no spontaneous malignant transformation ability. From this evidence, HNK1 cells were found to be EpCAM(+)/CD133(-) hepatic progenitor cells without spontaneous malignant transformation ability. We therefore conclude that HNK1 cells could be useful for experimental and therapeutic applications.

Lipocalin-2 negatively modulates the epithelial-to-mesenchymal transition in hepatocellular carcinoma through the epidermal growth factor (TGF-beta1)/Lcn2/Twist1 pathway

Lipocalin-2 (Lcn2) is preferentially expressed in hepatocellular carcinoma (HCC). However, the functional role of Lcn2 in HCC progression is still poorly understood, particularly with respect to its involvement in invasion and metastasis. The purpose of this study was to investigate whether Lcn2 is associated with the epithelial-mesenchymal transition (EMT) in HCC and to elucidate the underlying signaling pathway(s). Lcn2 was preferentially expressed in well-differentiated HCC versus liver cirrhosis tissues, and its expression was positively correlated with the stage of HCC. The characteristics of EMT were reversed by adenoviral transduction of Lcn2 into SH-J1 cells, including the down-regulation of N-cadherin, vimentin, alpha-smooth muscle actin, and fibronectin, and the concomitant up-regulation of CK8, CK18, and desmoplakin I/II. Knockdown of Lcn2 by short hairpin RNA (shRNA) in HKK-2 cells expressing high levels of Lcn2 was associated with EMT. Epidermal growth factor (EGF) or transforming growth factor beta1 (TGF-β1) treatment resulted in down-regulation of Lcn2, accompanied by an increase in Twist1 expression and EMT in HCC cells. Stable Lcn2 expression in SH-J1 cells reduced Twist1 expression, inhibited cell proliferation and invasion in vitro, and suppressed tumor growth and metastasis in a mouse model. Furthermore, EGF or TGF-β1 treatment barely changed EMT marker expression in SH-J1 cells ectopically expressing Lcn2. Ectopic expression of Twist1 induced EMT marker expression even in cells expressing Lcn2, indicating that Lcn2 functions downstream of growth factors and upstream of Twist1.

CONCLUSION

Together, our findings indicate that Lcn2 can negatively modulate the EMT in HCC cells through an EGF (or TGF-β1)/Lcn2/Twist1 pathway. Thus, Lcn2 may be a candidate metastasis suppressor and a potential therapeutic target in HCC.

Activation of mammalian target of rapamycin complex 1 (mTORC1) and Raf/Pyk2 by growth factor-mediated Eph receptor 2 (EphA2) is required for cholangiocarcinoma growth and metastasis

Eph receptor 2 (EphA2) overexpression is frequently accompanied by the loss of its cognate ligand during tumor progression. However, the molecular mechanism of this ligand-independent promotion of tumor by EphA2 remains unclear in highly malignant and fatal cholangiocarcinoma (CC). We examined the biological role of EphA2 in tumor growth and metastasis in CC tissues and cells according to the degree of differentiation and we explored the downstream signaling pathways of EphA2. Growth factor-mediated EphA2 overexpression itself leads to the activation of the mammalian target of rapamycin complex 1 (mTORC1) and extracellular signal-regulated kinase (ERK) pathways through ligand-independent activation of EphA2 (phosphorylation of S897). An in vitro soft agar assay and in vivo orthotopic or subcutaneous tumor model showed that EphA2 enhanced colony formation and accelerated tumor growth, and which seemed to be mainly associated with Akt (T308)/mTORC1 activation. Aberrant expression and activation of EphA2 was also associated with poorer differentiation and higher metastatic ability. Enhanced metastatic ability was also observed in an orthotopic tumor model or lung metastasis model, correlating with Pyk2(Y402)/c-Src/ERK activation in addition to activation of the canonical Raf/MEK/ERK pathway. The mTORC1 and Raf/Pyk2 pathways also appeared to affect each other. These results suggest that growth factor-mediated EphA2 might be involved in tumor growth and metastasis through activation of the mTORC1 and Raf/Pyk2 pathways. Therapeutic strategies that target EphA2 and its downstream effectors may be useful to control CC. (HEPATOLOGY 2013;57:2248-2260).

Pro-oncogenic potential of NM23-H2 in hepatocellular carcinoma

NM23 is a family of structurally and functionally conserved proteins known as nucleoside diphosphate kinases (NDPK). There is abundant mRNA expression of NM23-H1, NM23-H2, or a read through transcript (NM23-LV) in the primary sites of hepatocellular carcinoma (HCC). Although the NM23-H1 protein is implicated as a metastasis suppressor, the role of NM23-H2 appears to be less understood. Thus, the aim of this study was to examine whether NM23-H2 is associated with hepatocarcinogenesis. The level of NM23-H2 expression in tumor tissues and the surrounding matrix appeared to be independent of etiology and tumor differentiation. Its subcellular localization was confined to mainly the cytoplasm and to a lesser extent in the nucleus. Ectopic expression of NM23-H2 in NIH3T3 fibroblasts and HLK3 hepatocytes showed a transformed morphology, enhanced focus formation, and allowed anchorage-independent growth. Finally, NIH3T3 fibroblasts and HLK3 hepatocytes stably expressing NM23-H2 produced tumors in athymic mice and showed c-Myc over-expression. In addition, NF-κB and cyclin D1 expression were also increased by NM23-H2. Lentiviral delivery of NM23-H2 shRNA inhibited tumor growth of xenotransplanted tumors produced from HLK3 cells stably expressing NM23-H2. Collectively, these results indicate that NM23-H2 may be pro-oncogenic in hepatocarcinogenesis.

The fluxes of CO2 from grazed and fenced temperate steppe during two drought years on the Inner Mongolia Plateau, China

The CO(2) flux was measured by the eddy covariance method on a temperate Leymus chinensis steppe over a period of 17 months spanning two consecutive growing seasons. The amount of precipitation was nearly normal, but it was low in the early and high in the late growing period in 2006. In the 2007 growing season, the amount of precipitation was about 45% less than the multi-year average and more evenly distributed. Comparisons were made between a moderately grazed site and a 28-year-old fenced site. The maximum instantaneous CO(2) release and uptake rates were 0.12 (May) and -0.11mg CO(2)m(-2)s(-1) (July) at the fenced site, and 0.11 and -0.16mg CO(2)m(-2)s(-1) (both in July) at the grazed site. In both growing seasons, the grazed site always had a higher daily uptake rate or lower release rate than the fenced site. The grazed site was a CO(2) sink during the growing season of 2007 and a CO(2) source in the growing season of 2006, whereas the fenced site was a CO(2) source in both seasons. Lower precipitation decreased CO(2) loss during the growing season more in the grazed site than in the fenced site, mainly because of depression of total ecosystem respiration (R(e)) in the former and stimulation in the latter. During the dormant season (from October to April), the fenced and grazed sites released 60.0 and 32.4g of C per m(2), respectively. Path analysis showed that temperature had the greatest effect on daily variation of ecosystem CO(2) exchange during the growing seasons at the two study sites. The results suggest that decrease of precipitation and/or increase of temperature will likely promote C loss from L. chinensis steppes, whether fenced or grazed, and that a grazed site is more sensitive.

Enhancement of parthenolide-induced apoptosis by a PKC-alpha inhibition through heme oxygenase-1 blockage in cholangiocarcinoma cells

Cholangiocarcinoma (CC) is a chemoresistant intrahepatic bile duct carcinoma with a poor prognosis. The aims of this study were to identify molecular pathways that enhance sesquiterpene lactone parthenolide (PTL)-induced anticancer effects on CC cells. The effects of PTL on apoptosis and hemoxygenase-1 (HO-1) induction were examined in CC cell lines. The enhancement of PTL-mediated apoptosis by modulation of HO-1 expression and the mechanisms involved were also examined in an in vitro cell system. Low PTL concentrations (5 to 10 microM) led to Nrf2-dependent HO-1 induction, which attenuated the apoptogenic effect of PTL in Choi-CK and SCK cells. PTL-mediated apoptosis was enhanced by the protein kinase C-alpha inhibitor Ro317549 (Ro) through inhibition of expression and nuclear translocation of Nrf2, resulting in blockage of HO-1 expression. Finally, HO-1 silencing resulted in enhancement of apoptotic cell death in CC cells. The combination of PTL and Ro efficiently improved tumor growth inhibition compared to treatment with either agent alone in an in vivo subcutaneous tumor model. In conclusion, the modulation of HO-1 expression substantially improved the anticancer effect of PTL. The combination of PTL and Ro could prove to be a valuable chemotherapeutic strategy for CC.

Genome-wide expression patterns associated with oncogenesis and sarcomatous transdifferentation of cholangiocarcinoma

Background

The molecular mechanisms of CC (cholangiocarcinoma) oncogenesis and progression are poorly understood. This study aimed to determine the genome-wide expression of genes related to CC oncogenesis and sarcomatous transdifferentiation.

Methods

Genes that were differentially expressed between CC cell lines or tissues and cultured normal biliary epithelial (NBE) cells were identified using DNA microarray technology. Expressions were validated in human CC tissues and cells.

Results

Using unsupervised hierarchical clustering analysis of the cell line and tissue samples, we identified a set of 342 commonly regulated (>2-fold change) genes. Of these, 53, including tumor-related genes, were upregulated, and 289, including tumor suppressor genes, were downregulated (<0.5 fold change). Expression of SPP1, EFNB2, E2F2, IRX3, PTTG1, PPARγ, KRT17, UCHL1, IGFBP7 and SPARC proteins was immunohistochemically verified in human and hamster CC tissues. Additional unsupervised hierarchical clustering analysis of sarcomatoid CC cells compared to three adenocarcinomatous CC cell lines revealed 292 differentially upregulated genes (>4-fold change), and 267 differentially downregulated genes (<0.25 fold change). The expression of 12 proteins was validated in the CC cell lines by immunoblot analysis and immunohistochemical staining. Of the proteins analyzed, we found upregulation of the expression of the epithelial-mesenchymal transition (EMT)-related proteins VIM and TWIST1, and restoration of the methylation-silenced proteins LDHB, BNIP3, UCHL1, and NPTX2 during sarcomatoid transdifferentiation of CC.

Conclusion

The deregulation of oncogenes, tumor suppressor genes, and methylation-related genes may be useful in identifying molecular targets for CC diagnosis and prognosis.

EFNA1 ligand and its receptor EphA2: potential biomarkers for hepatocellular carcinoma

Novel biomarkers are needed for early detection and progression evaluation of hepatocellular carcinoma (HCC). The purpose of this study was to identify useful biomolecular markers for HCC. The 26 genes that encode membrane or secretory proteins were identified from cDNA microarray data. We further examined the expression of EFNA1 and its receptor EphA2 and determined their biological implications during the development and progression of HCC. The EFNA1 mRNA was overexpressed in most HCCs as compared with its expression in corresponding nontumor tissues (36 out of 40 cases, 90%), but EphA2 expression was noted in only half of the HCC tissues (20 of 40 cases, 50%). In most of the hepatoma cell lines, the EFNA1 protein expression was positively associated with alpha-fetoprotien (AFP) expression but inversely associated with EphA2 expression. Furthermore, EFNA1 levels were detectable in the supernatant of the cultured hepatoma cells and in the serum of patients with HCC. In contrast, EphA2 expression was prominent in highly invasive hepatoma cells, and its overexpression was significantly correlated with decreased differentiation (r = 0.0248, p < 0.010) and poor survival (p = 0.0453) for HCC patients. EFNA1 and EphA2 may be useful serum markers for the detection of HCC development and progression, respectively.

Genetic and expression alterations in association with the sarcomatous change of cholangiocarcinoma cells

Cholangiocarcinoma (CC) is an intrahepatic bile duct carcinoma with a high mortality rate and a poor prognosis. Sarcomatous change/epithelial mesenchymal transition (EMT) of CC frequently leads to aggressive intrahepatic spread and metastasis. The aim of this study was to identify the genetic alterations and gene expression pattern that might be associated with the sarcomatous change in CC. Previously, we established 4 human CC cell lines (SCK, JCK1, Cho-CK, and Choi-CK). In the present study, we characterized a typical sarcomatoid phenotype of SCK, and classified the other cell lines according to tumor cell differentiation (a poorly differentiated JCK, a moderately differentiated Cho-CK, and a well differentiated Choi-CK cells), both morphologically and immunocytologically. We further analyzed the genetic alterations of two tumor suppressor genes (p53 and FHIT) and the expression of Fas/FasL gene, well known CC-related receptor and its ligand, in these four CC cell lines. The deletion mutation of p53 was found in the sarcomatoid SCK cells. These cells expressed much less Fas/FasL mRNAs than did the other ordinary CC cells. We further characterize the gene expression pattern that is involved in the sarcomatous progression of CC, using cDNA microarrays that contained 18,688 genes. Comparison of the expression patterns between the sarcomatoid SCK cells and the differentiated Choi-CK cells enabled us to identify 260 genes and 247 genes that were significantly over-expressed and under-expressed, respectively. Northern blotting of the 14 randomly selected genes verified the microarray data, including the differential expressions of the LGALS1, TGFBI, CES1, LDHB, UCHL1, ASPH, VDAC1, VIL2, CCND2, S100P, CALB1, MAL2, GPX1, and ANXA8 mRNAs. Immunohistochemistry also revealed in part the differential expressions of these gene proteins. These results suggest that those genetic and gene expression alterations may be relevant to the sarcomatous change/EMT in CC cells.

[Repair of humeral fracture and non-union with transfer of vascularized periosteal flap]

OBJECTIVE

To study the results of humeral fracture and non-union repaired by vascularized periosteal flap transfer.

METHODS

The clinical data of humeral fracture and non-union in 23 cases were analysized retrospectively since 1995. Among them, minuted or several segmental fracture in 12 cases, non-union in 11 cases, and following injury of radial nerve in 7 cases. The operative method was open reduction, inner or external fixation with vascularized periosteal flap transfer.

RESULTS

The period of follow-up was 6 months to 2 years. The repair result of all patients was excellent and good, but elbow joint motion in 2 cases of non-union was not satisfactory. The periosteal flap had good osteogenic ability. The period of bone union was 2 to 5 months in humeral fracture and non-union. And function of radial nerve was recovery.

CONCLUSION

Transfer of distal humeral periosteal flap pedicled with radial collateral vessels is a better method for humeral fracture and non-union.

[Clinical application of the medial multiplex flap pedicled with the posterior tibial vessel]

OBJECTIVE

To investigate the clinical results of the medial multiplex flap pedicled with the posterior tibial vessel.

METHODS

Twelve cases with soft tissue defects and bone defects of limbs were treated with the medial multiplex flap pedicled with the posterior tibial vessel from September 1992 to May 1999. Among them, bone and soft tissue defects following opened fracture in 7 cases, chronic ulcer following chronic osteomyelitis in 2 cases, melanoepithelioma in 2 cases, bone and soft tissue defects following osteoma resection in 1 case. The bone defect area was from 2.5 cm x 5.0 cm to 4.5 cm x 11.0 cm. Free graft was performed in 5 cases, bridged transposition in 3 cases and reversal transposition in 4 cases, among them, periosteal myocutaneous flap with autogenous or allogeneic bone grafting in 8 cases, myocutaneous flap in 4 cases. The area of the flaps from 6 cm x 8 cm to 12 cm x 25 cm.

RESULTS

All flaps were healed by first intention, but in the distal fragments of bigger flaps were partially necrosed in 2 cases. In 10 cases bone healing were obtained after 16 weeks of operation according to the X-ray photos. All cases were followed up from 6 to 18 months. All cases achieved satisfactory result but 1 case died because of lung metastasis of osteoma.

CONCLUSION

The multiplex graft pedicled with the posterior tibial vessel is an ideal graft for repairing the large soft tissue defects and bone defects, because it has such advantages as adequate blood supply, big vascular diameter, long pedicle and big dermatomic area.

[The applied anatomy of transposition of the distal dorsal ulna bone flap pedicled with dorsal metacarpal artery]

OBJECTIVE

To investigate the anatomic basis for transposition of the distal dorsal ulna bone flap pedicled with dorsal metacarpal artery to repair the defect of the 3rd or 4th and 5th metacarpal bone head.

METHODS

In 30 adult cadaveric upper limbs, the branches and constitutions of the dorsal carpal arterial networks were observed.

RESULTS

The dorsal carpal arterial networks were consisted of the dorsal carpal branches of ulnar and radial arteries, the terminal branches of posterior interosseous artery and the dorsal carpal branch of anterior interosseous artery, and then the 2nd, 3rd, 4th dorsal metacarpal branches were originated from the networks. The dorsal metacarpal branches were anastomosed with the deep branches of deep palmar arch to constitute the dorsal metacarpal artery.

CONCLUSION

Transposition of the distal dorsal ulna bone flap pedicled with the 3rd, 4th dorsal metacarpal arteries can be used in repairing the defect of 3rd, 4th and 5th metacarpal bone head.

[Transposing the great trochanter bone flap pedicaled with the deep branch of the medial circumflex artery in repair of necrotic femoral head]

The transposition of the greater trochanter bone flap pedicled with the deep branch of the medial circumflex artery was designed as a new therapeutic method for the treatment of early ischemic necrosis of the femoral head in adults. Bone flap was successfully used in 15 limbs of 13 patients. Applied anatomy, operative indications and procedure of the bone flap was introduced.

[Experimental study on cellular electrophysiology of Viscum coloratum flavonoid in treating tachyarrhythmias]

Viscum Coloratum Flavonoid (VCF) is one of the dihydro-flavonoids isolated and purified from the stem and leaf of Viscum Coloratum. It was proved both experimentally and clinically to have the effects of anti-tachyarrhythmias. The mechanism of this effect, however, was unclear. In this study, the effects of the drug on the fast response action potentials (FAP) in canine Purkinje fibers and guinea pig ventricular myocardial cells were investigated by glass-microelectrode technique. The results indicated that 0.1 mg/ml VCF accelerated the repolarizations of 2nd and 3rd phase of FAP, shortened action potential duration (APD), and slightly shortened effective refractory period (ERP) (canine) or unchanged (guinea pig). delta ERP/delta APD ratio was increased, therefore, ERP was relatively prolonged. All effects appeared after using the drug for 2 minutes, reached stable status after 10 minutes, and disappeared after washing off the drug for 15 minutes. It was suggested that VCF was the drug which exerted effects rapidly, maintained effects shortly, and had effects reversibly. The cellular electrophysiologic mechanisms of VCF on anti-tachyarrhythmias should be attributed to prolong the ERP relatively and abolish the reentry. This drug is particularly applicable to the tachyarrhythmias due to reentry.

[Effects of Viscum coloratum flavonoids on fast response action potentials of hearts]

The effects of the total flavonoids of Viscum coloratum (VCF) on the fast response action potentials (FAP) of canine Purkinje fibers and guinea pig ventricular papillary muscles were studied by glass-microelectrode technique. The effects of VCF on the ionic currents through cellular membrane were analysed with selective ion blockers (CsCl, verapamil, and TEA+), respectively. VCF (100 micrograms.ml-1) accelerated the repolarization of FAP and increased delta ERP/delta APD ratio, which were related to decreasing Isi and increasing Ix. It was suggested that the anti-tachyarrhythmic mechanism of VCF was attributed to prolonging ERP relatively and to abolishing reentrant excitation.

Assessment of Nd:YAG laser via metal cap and sapphire tip delivery system. An experimental and clinical investigation

Sixteen segments of normal human aorta were irradiated by Nd:YAG laser beam delivered via domestically made metal cap and sapphire tip fibre systems. It was found that the metal tip fibre caused more target tissue damage and adhesion than the sapphire tip fibre. The sapphire tip fibre caused an ablation crater with a smoother edge, less carbonization layer and smaller thermal necrotic zone than the metal tip did. The metal cap and sapphire tip fibre were applied to 2 cases of iliac artery stenosis and 5 cases of coronary stenosis, all showing an immediate ablation.

[Changes in the deformability of erythrocytes and 2,3-DPG in coronary artery stenosis]

The changes of deformability of RBC and 2,3-DPG in RBC in patients with coronary artery stenosis and the influence of some factors on them were studied. The results showed that: (1) the deformability index was inversely proportional to the degree of lesions of coronary vessels (P less than 0.01); (2) the 2,3-DPG was inversely proportional to the degree of lesions of coronary vessels (P less than 0.01); (3) there was a significant decrease in deformability index after using contrast medium; (4) Saliva may increase deformability of RBC and 2,3-DPG; (5) Nifedipine may increase deformability of RBC. These results showed: (1) the possible existence of microcirculatory dysfunction in coronary artery disease and in parallel of impaired deformability of RBC; (2) the possibility of normalization of the decreased deformability of 2,3-DPG in RBC by Salvia; (3) the possibility of increase of velocity of blood flow in microcirculation in coronary artery disease by Salvia.

[Extent of treatment of early carcinoma of the uterine cervix--local treatment of 198 stage I patients]

The extent of treatment of early carcinoma of the uterine cervix is still controversial. 198 patients with Stage I carcinoma of the uterine cervix who received local treatment for the primary tumor are summarized, 107 with early invasive carcinoma and 91 with invasive cancer. Microscopic examination showed that 62.2% of the patients had lesions less than 1 cm in diameter. In 82.8% of the patients, the invasion was confined to the cervical ring by pathological examination. The accuracy of multiple biopsies was 79.3%. Of 198 patients, 124 received intracavitary radiotherapy only, 73 hysterectomy and 1 cone resection of the uterine cervix. All of them were followed for 5 years or more. The 5-year survival rate was 98% and none of them died of cancer. The author considers that the extent of treatment of early invasive carcinoma can be localized. For localized invasive carcinoma (stage Ib) with lesion less than 1 cm and extent of invasion less than half of the uterine cervix ring as confirmed by biopsy, the treatment of regional lymph nodes can be omitted. Multiple biopsies may replace diagnostic cone resection in most instances.

[Pyometra and radiotherapy of cancer of the uterine cervix--analysis of 282 patients]

From March 1958 to December 1980, 11284 patients with cancer of uterine cervix were treated with radiotherapy in our hospital. Among them, 282 were complicated with pyometra with an incidence of 2.5%. The incidence of pyometra was higher in patients treated by combined intracavitary with external irradiation than by other radiation methods. 74.1% was diagnosed during the manipulation of intracavitary therapy. Escherichia coli comprised 46.5% by culture. The 5 year survival rate was lower in patients with pyometra than without it. The patients who had a temperature over 38 degrees C and uterus enlarged to more than 6 weeks of pregnancy had a bad prognosis. It was even worse for patients whose pyometra did not heal or developed at the end of radiation. Endometrial biopsy was done in 36 patients with pyometra and cancer cells were seen in 55.6% of them. Endometrial biopsy positive rate reached to 77.8% in the patients whose pyometra was not cured or occurred after radiotherapy. This is the main reason of the poor prognosis. The authors believe that endometrial and cervical biopsy should be taken for cancer of uterine cervix complicated with pyometra; for biopsy positive patients during the treatment, the intracavitary dose should be increased; for positive patients after radiotherapy, operation is strongly indicated.

[192Ir afterloading machine for intracavitary radiotherapy--first unit installed in China]

This paper presents the source, applicators and treatment results of the first 192Ir afterloading machine manufactured at home. The intrauterine source can effect pendulous displacements in linear or non-linear patterns without preparatory dilatation. The vagina source can assume palisade and erect position. Satisfactory dose distributions are possible by various arrangements of the vaginal applicators as required clinically. From Oct. 1984 to Dec. 1985, 82 patients with cervical malignancies were treated by this machine. The tumor mass in all patients disappeared before the conclusion of treatment. There was no local recurrence with the longest follow-up of one year as compared to the tumor inhibition rate of 91.9% by the traditional method during the same period. These results suggest that this facility be satisfactory and that the traditional intracavitary treatment could be replaced.

[Malignancy of the uterine body after radiotherapy for carcinoma of uterine cervix--report of 12 cases]

Twelve cases of malignancy of the uterine body occurred 5-19 years after radiotherapy for 8,704 cases of carcinoma of cervix-an incidence of 0.14%. 10 cases were malignant mixed mesodermal tumor and 2 endometrial carcinoma. The radiation dose varied from 5,500 to 12,000 rad to the area of uterine body. Eight patients had vaginal discharge and 4 were asymptomatic in the follow-up examination in which enlarged uterus was found in all except one. The tumor had extented out of the uterus in 6 patients. 6 of the 12 patients were diagnosed by endometrial biopsy before treatment. Eight patients were treated by operation, 3 by radiation and 1 was untreated. Eleven patients died within 3 years, one recurred in 4.5 years after treatment. It is believed that the malignant tumor of the uterine body is closely related to radiotherapy and the prognosis is poor. Therefore, in the follow-up examination, if vaginal discharge and enlarged uterus are found, endometrial biopsy should be done to ensure correct diagnosis and early operation in order to obtain a better result.

Effect of higenamine on action potential of ventricular myocardial cells

Action potentials of isolated ventricular myocardial fibers of pigs and the electrophysiological actions of dl-demethylcoclaurine (DMC) or higenamine on the porcine myocardial cells were studied by glass microelectrodes. The action potentials of porcine ventricular myocardial fibers were similar to those of other mammalian hearts. Amplitude of the action potential was 115 +/- 9 mV, duration of action potential 242 +/- 30 ms, resting membrane potential -85 +/- 5 mV and the maximum rise of depolarization of action potential 151 +/- 27 V/s. After perfusion with normal Tyrode's solution containing DMC 5 micrograms/ml, the amplitude of action potential was increased and the duration of action potential was prolonged, the amplitude and duration of the plateau of action potential were increased and the slope of phase 2 of action potential was reduced (p less than 0.05). The resting potential, the slope of phase 3 and the maximum depolarization rate of phase 0 of action potential did not change. In Tyrode's solution containing Mn++ 3 mM, these electrophysiological actions of DMC disappeared. DMC may abolish the conduction block induced by K+-rich solution. In Tyrode's solution containing K+ 32 mM, the upstroke of action potential showed 2 phases under influence of DMC. The second phase disappeared when Mn++ was added. All findings indicate that DMC can be considered as an activator of the slow channel. The electrophysiological mechanism and clinical significance of DMC were discussed.