[Study on the comparative analysis of the efficacy of transmesenteric vein extrahepatic portosystemic shunt and transjugular intrahepatic portosystemic shunt in the treatment of cavernous transformation of portal vein]

Objective: To compare the safety and efficacy of transmesenteric vein extrahepatic portosystemic shunt (TEPS) and transjugular intrahepatic portosystemic shunt (TIPS) in the treatment of cavernous transformation of the portal vein (CTPV). Methods: The clinical data of CTPV patients with patency or partial patency of the superior mesenteric vein treated with TIPS or TEPS treatment in the Department of Vascular Surgery of Henan Provincial People's Hospital from January 2019 to December 2021 were selected. The differences in baseline data, surgical success rate, complication rate, incidence rate of hepatic encephalopathy, and other related indicators between TIPS and TEPS group were statistically analyzed by independent sample t-test, Mann-Whitney U test, and Chi-square test. Kaplan-Meier survival curve was used to calculate the cumulative patency rate of the shunt and the recurrence rate of postoperative portal hypertension symptoms in both groups. Results: The surgical success rate (100% vs. 65.52%), surgical complication rate (6.67% vs. 36.84%), cumulative shunt patency rate (100% vs. 70.70%), and cumulative symptom recurrence rate (0% vs. 25.71%) of the TEPS group and TIPS group were statistically significantly different (P < 0.05). The time of establishing the shunt [28 (2141) min vs. 82 (51206) min], the number of stents used [1 (12) vs. 2 (15)], and the length of the shunt [10 (912) cm vs. 16 (1220) cm] were statistically significant between the two groups (t = -3.764, -4.059, -1.765, P < 0.05). The incidence of postoperative hepatic encephalopathy in the TEPS group and TIPS group was 6.67% and 15.79% respectively, with no statistically significant difference (Fisher's exact probability method, P = 0.613). The pressure of superior mesenteric vein decreased from (29.33 ± 1.99) mmHg to (14.60 ± 2.80) mmHg in the TEPS group and from (29.68 ± 2.31) mmHg to (15.79 ± 3.01) mmHg in TIPS group after surgery, and the difference was statistically significant (t = 16.625, 15.959, P < 0.01). Conclusion: The best indication of TEPS is in CTPV patients with patency or partial patency of the superior mesenteric vein. TEPS improves the accuracy and success rate of surgery and reduces the incidence of complications.

[Analysis of the short-and medium-term curative effect of TIPS approach combined with AngioJet thrombus aspiration technology treatment in acute portal vein thrombosis]

Objective: To evaluate the short- and medium-term clinical efficacy of TIPS approach combined with AngioJet thrombus aspiration technology treatment in acute portal vein thrombosis. Methods: 63 cases with acute portal vein thrombosis treated in our center from May 2017 to July 2019 were studied retrospectively, including 49 males and 14 females, aged 35-61 (46 ± 5) years. TIPS approach (with/without) combined with Angiojet thrombus aspiration and gastroesophageal varices embolization was performed simultaneously according to the patient's condition. Regular follow-up for 3-33 (22 ± 3) months after surgery was used to observe the curative effect. Results: The technical success rate was 100%. Portal vein and superior mesenteric vein blood flow were returned to normal after the operation. Two cases of biliary tract injury were untreated. Simultaneously, two cases of intrahepatic arteriovenous fistula were treated with superselective arterial embolization. During the follow-up period, 47 cases (74.61%) had complete portal vein recanalization, 13 cases (20.63%) had partial recanalization, 3 cases (4.76%) had complete portal cavernoma, 7 cases (11.11%) had symptomatic hepatic encephalopathy, 1 case had received artificial liver treatment (1.59%), 1 case had peptic ulcer (11.11%), 6 cases (9.52%) had lost to follow-up, and there was no portal hypertension-related bleeding or death. Conclusion: TIPS approach combined with AngioJet thrombus aspiration technology is safe, effective and feasible in the treatment of acute portal vein thrombosis, and the short- and medium-term clinical effects are satisfactory.

The suppression effect of light rare earth elements on proliferation of two cancer cell lines

To study the suppression effect of light rare earth elements (RE) on proliferation of two cancer cell lines. Two cancer cell lines PAMC82 and K562 were used to examine their colony-forming ability in soft agar, microtubule structure, calmodulin levels and regulation of some gene expressions by Northern blot analysis with and without treatment by RE. The results showed that on soft agar culture the colony-forming ability of human gastric cancer cell line PAMC82 treated by RE chloride decreased and the PAMC82 cell microtubule abnormal structure became normal. The calmodulin (CaM) levels decreased in human leukemia cells (K562) treated with cerium chloride and neodymium chloride. The Northern blot analysis revealed marked up-regulation of p53, p16(MTS1), p21 (WAF1) gene expressions in PAMC82 cells treated with lanthanum chloride and cerium chloride, as compared to control PAMC82 cells. The light rare earth elements studied have certain suppression effects on proliferation of cancer cells. This effect might be related to the decrease of calmodulin and up-regulation of some gene expressions in cancer cells.

Smooth muscle cell surface tissue factor pathway activation by oxidized low-density lipoprotein requires cellular lipid peroxidation

Tissue factor, which is expressed in vascular lesions, increases thrombin production, blood coagulation, and smooth muscle cell proliferation. We demonstrate that oxidized low-density lipoprotein (LDL) induces surface tissue factor pathway activity (ie, activity of the tissue factor:factor VIIa complex) on human and rat smooth muscle cells. Tissue factor messenger RNA (mRNA) was induced by oxidized LDL or native LDL; however, native LDL did not markedly increase tissue factor activity. We hypothesized that oxidized LDL mediated the activation of the tissue factor pathway via an oxidant-dependent mechanism, because antioxidants blocked the enhanced tissue factor pathway activity by oxidized LDL, but not the increased mRNA or protein induction. We separated total lipid extracts of oxidized LDL using high-performance liquid chromatography (HPLC). This yielded 2 major peaks that induced tissue factor activity. Of the known oxysterols contained in the first peak, 7alpha- or 7beta-hydroxy or 7-ketocholesterol had no effect on tissue factor pathway activity; however, 7beta-hydroperoxycholesterol increased tissue factor pathway activity without induction of tissue factor mRNA. Tertiary butyl hydroperoxide also increased tissue factor pathway activity, suggesting that lipid hydroperoxides, some of which exist in atherosclerotic lesions, activate the tissue factor pathway. We speculate that thrombin production could be elevated via a mechanism involving peroxidation of cellular lipids, contributing to arterial thrombosis after plaque rupture. Our data suggest a mechanism by which antioxidants may offer a clinical benefit in acute coronary syndrome and restenosis.

Native and oxidized low density lipoprotein induction of tissue factor gene expression in smooth muscle cells is mediated by both Egr-1 and Sp1

Tissue factor, in association with factor VIIa, initiates the coagulation cascade. We studied the influences of two pathophysiological stimuli, native (unmodified) and oxidized low density lipoprotein, on tissue factor gene expression in a cell important in vascular remodeling and vascular diseases, the smooth muscle cell. Our results demonstrated that both lipoproteins significantly induced tissue factor gene expression in rat aortic smooth muscle cells; oxidized low density lipoprotein was slightly more potent. Both lipoproteins increased tissue factor mRNA in a concentration- and time-dependent manner. Results from nuclear run-on assays and mRNA stability experiments indicated that increased tissue factor mRNA accumulation in response to the lipoproteins was principally controlled at the transcriptional level. By using lipid extracts of low density lipoprotein or methylation of the intact lipoprotein to block receptor recognition, we showed that this lipoprotein induced tissue factor mRNA via both receptor-independent and receptor-augmented pathways. Transfection studies using a series of deleted tissue factor promoters revealed that a -143- to +106-base pair region of the rat tissue factor promoter contained regulatory elements required for lipoprotein-mediated induction. Electrophoretic mobility shift assays showed that the binding activities of the transcription factor Egr-1, but not Sp1, were markedly elevated in response to these lipoproteins. Transfection of site-directed mutants of the tissue factor (TF) promoter demonstrated that not only Egr-1 but also Sp1 cis-acting elements in the TF (-143) promoter construct were necessary for optimal TF gene induction. Our data show for the first time that both low density lipoprotein and oxidized low density lipoprotein induce tissue factor gene expression in smooth muscle cells and that this tissue factor gene expression is mediated by both Egr-1 and Sp1 transcription factors.

Identification of a novel PSD-95/Dlg/ZO-1 (PDZ)-like protein interacting with the C terminus of presenilin-1

Presenilin-1 (PS-1) is the most causative Alzheimer gene product, and its function is not well understood. In an attempt to elucidate the function of PS-1, we screened a human brain cDNA library for PS-1-interacting proteins using the yeast two-hybrid system and isolated a novel protein containing a PSD-95/Dlg/ZO-1 (PDZ)-like domain. This novel PS-1-associated protein (PSAP) shares a significant similarity with a Caenorhabditis elegans protein of unknown function. Northern blot analysis revealed that PSAP is predominantly expressed in the brain. Deletion of the first four C-terminal amino acid residues of PS-1, which contain the PDZ domain-binding motif (Gln-Phe-Tyr-Ile), reduced the binding activity of PS-1 toward PSAP 4-fold. These data suggest that PS-1 may associate with a PDZ-like domain-containing protein in vivo and thus may participate in receptor or channel clustering and intracellular signaling events in the brain.

LDL increases inactive tissue factor on vascular smooth muscle cell surfaces: hydrogen peroxide activates latent cell surface tissue factor

BACKGROUND

Tissue factor, which is required for the initiation of the extrinsic coagulation cascade, is known to be upregulated in cells within atherosclerotic lesions, including smooth muscle cells. Tissue factor expression on the smooth muscle cell surface could be of pathological significance as a contributor to plaque growth, thrombus formation, and the acute coronary syndrome after plaque rupture.

METHODS AND RESULTS

In this study, we show that LDL increased tissue factor mRNA and cell surface protein in smooth muscle cells without a marked increase in surface tissue factor activity. Hydrogen peroxide activated tissue factor on the cell surface but did not increase tissue factor mRNA or cell surface protein. Sequentially added LDL and hydrogen peroxide increased mRNA, cell surface protein, and activity; surface activity was greater than that observed with hydrogen peroxide alone. The action of hydrogen peroxide did not involve a regulatory mechanism associated with the cytoplasmic tail of tissue factor because a truncated tissue factor lacking the cytoplasmic tail was activated by hydrogen peroxide.

CONCLUSIONS

These results suggest a novel 2-step pathway for increased tissue factor activity on smooth muscle cell surfaces in which lipoproteins regulate synthesis of a latent tissue factor and oxidants activate the protein complex.

Transcriptional regulation of the tissue factor gene in human epithelial cells is mediated by Sp1 and EGR-1

Tissue factor (TF) gene expression is rapidly induced in epithelial cells by phorbol 12-myristate 13-acetate and serum. We have shown that this induction is mediated by a novel serum response region (SRR) (-111 to +14 bp) within the human TF promoter. In this study, we characterized cis-acting genetic elements within the SRR that regulated basal and inducible expression of the TF gene in HeLa cells. Gel mobility shift assays using oligonucleotides spanning the entire SRR identified three 12-base pair (bp) motifs within subregions 1, 2, and 3 that bound constitutively expressed Sp1 and inducibly expressed EGR-1. Analysis of protein binding to these 12-bp motifs by competition with Sp1 and EGR-1 sites, mutation, and antibody supershift experiments indicated that they each contained distinct EGR-1 and Sp1 sites that overlapped by 6 bp. Functional studies using HeLa cells transfected with plasmids containing the wild-type TF promoter (-111 to +14 bp) or derivatives containing mutations in the three Sp1 and/or EGR-1 sites examined basal and inducible expression. The Sp1 sites mediated basal promoter activity, and both Sp1 and EGR-1 sites were required for maximal induction of the TF promoter by phorbol 12-myristate 13-acetate or serum. These data indicated that TF gene expression in HeLa cells was regulated by both Sp1 and EGR-1.

The LIF response element of the alpha 2 macroglobulin gene confers LIF-induced transcriptional activation in embryonal stem cells

Leukaemia Inhibitory Factor (LIF), an interleukin 6 (IL-6)-type cytokine, is an essential growth factor for murine embryonal stem cells. The LIF-receptor was known in these cells, but the cell-internal part of the signal cascade and the transcription factors through which LIF controls its growth-promoting target genes in embryonal stem cells, had not been identified. This study shows that the type II IL-6-response element of the rat alpha 2 macroglobulin (alpha 2M) gene, which mediates IL-6- and LIF-responses in hepatic cells, also functioned as a LIF-response element (LIF-RE) in ES1 embryonal stem cells and P19 embryonal carcinoma cells. It conferred transcriptional activation by LIF of transfected reporter constructs in these cells. A characteristic DNA-binding activity interacting with this LIF-RE was induced by treatment of these cells with LIF. The complex between this activity and the LIF-RE had identical electrophoretic mobility, sequence-specificity and kinetics of induction as the complex with the corresponding LIF-response factor (LIF-RF) from hepatic cells. The transcription factor STAT3 was part of this complex, as shown by its reactivity with anti-STAT3 antibodies. Withdrawal of LIF from ES1 cells caused the induction of differentiation and the disappearance of this DNA-binding activity. Simultaneously, the surface density of high-affinity LIF receptors was reduced approximately 10-fold.

Integrin regulation of an inflammatory effector gene. Direct induction of the tissue factor promoter by engagement of beta 1 or alpha 4 integrin chains

Inflammatory genes are regulated in cells of monocyte (Mo) lineage by a variety of cellular encounters, including adhesion mediated by integrins. The role of the beta 1 family of integrins in the direct induction of immediate early gene expression was analyzed by using the tissue factor (TF) gene. Engagement of alpha 4 or beta 1 on Mo, but not members of the beta 2 integrin family, with specific mAbs as surrogate ligands immediately and directly induced high level surface expression of TF, and accumulation of TF mRNA, as well as production of TNF-alpha and HIV-1 virus. The mechanism responsible for induction of TF gene transcription mediated by the engagement of alpha 4 or beta 1 was elucidated by using THP-1 monoblastic leukemia cells. Functional analysis of plasmids containing the TF promoter expressing the luciferase reporter gene identified a cis-acting integrin-responsive element (InRE), which contained two AP-1 sites as well as a single kappa B-like site. Mutation of either the AP-1 sites or kappa B-like site greatly diminished responsiveness to integrin engagement. This InRE also conferred responsiveness to a heterologous promoter in the same reporter plasmid. Binding of mAbs to either alpha 4 or beta 1 led to nuclear translocation of the c-Rel/p65 heterodimer that preferentially bound to the TF kappa B-like site. In contrast, constitutive binding of AP-1 proteins to the two AP-1 sites was not increased by alpha 4 or beta 1 integrin engagement. These studies expand knowledge of integrin regulation of immediate early gene expression in Mo and molecular encounters that are inferred to play an active role in Mo effector functions.

Integrin regulation of an inflammatory effector gene. Direct induction of the tissue factor promoter by engagement of beta 1 or alpha 4 integrin chains

Inflammatory genes are regulated in cells of monocyte (Mo) lineage by a variety of cellular encounters, including adhesion mediated by integrins. The role of the beta 1 family of integrins in the direct induction of immediate early gene expression was analyzed by using the tissue factor (TF) gene. Engagement of alpha 4 or beta 1 on Mo, but not members of the beta 2 integrin family, with specific mAbs as surrogate ligands immediately and directly induced high level surface expression of TF, and accumulation of TF mRNA, as well as production of TNF-alpha and HIV-1 virus. The mechanism responsible for induction of TF gene transcription mediated by the engagement of alpha 4 or beta 1 was elucidated by using THP-1 monoblastic leukemia cells. Functional analysis of plasmids containing the TF promoter expressing the luciferase reporter gene identified a cis-acting integrin-responsive element (InRE), which contained two AP-1 sites as well as a single kappa B-like site. Mutation of either the AP-1 sites or kappa B-like site greatly diminished responsiveness to integrin engagement. This InRE also conferred responsiveness to a heterologous promoter in the same reporter plasmid. Binding of mAbs to either alpha 4 or beta 1 led to nuclear translocation of the c-Rel/p65 heterodimer that preferentially bound to the TF kappa B-like site. In contrast, constitutive binding of AP-1 proteins to the two AP-1 sites was not increased by alpha 4 or beta 1 integrin engagement. These studies expand knowledge of integrin regulation of immediate early gene expression in Mo and molecular encounters that are inferred to play an active role in Mo effector functions.

Regulation of tissue factor gene expression in epithelial cells. Induction by serum and phorbol 12-myristate 13-acetate

Cell-specific expression of tissue factor (TF) in vivo is consistent with its primary role in hemostasis. In addition, TF expression is induced in cultured cells by a variety of agents, including serum and growth factors, which define the TF gene as a "primary response" gene. In this study we examined the signaling pathways and cis-acting regulatory elements required for induction of TF gene expression in HeLa cells in response to serum and the tumor promoter, phorbol 12-myristate 13-acetate (PMA). TF activity and mRNA were induced greater than sixfold in quiescent HeLa cells by serum and PMA. TF mRNA induction by both agonists required intracellular Ca2+ mobilization, whereas inhibition of protein kinase C abolished induction of the TF gene by PMA but had no effect on induction by serum. Functional studies demonstrated that a region of the human TF promoter between -96 and +121 bp contained regulatory elements required for serum and PMA induction. These data indicate that different signaling pathways regulate TF gene expression in response to serum and PMA, although the same cis-acting DNA elements may mediate induction.

Sensitive flame-photometric-detector analysis of thiodiglycolic acid in urine as a biological monitor of vinyl chloride

A simple and selective method to detect thiodiglycolic acid (TdGA) in urine by flame-photometric-detector (FPD) of gas chromatograph (GC) is described. The detection limit of this method is less than 1 ng without disturbances. Urine from 64 subjects exposed to different air concentration of vinyl chloride (VCM) from 0.3 ppm to more than 100 ppm in three groups and 78 subjects was detected in this way. A comparison of the results of these groups shows significant differences between the control and two exposed groups.