Endoscopic detection of esophageal low-grade squamous dysplasia: How to predict pathologic upgrades before treatment?

OBJECTIVE: In this study we aimed to predict the risk factors related to histopathologic upgrade after endoscopic submucosal dissection (ESD) in patients with pre-ESD esophageal squamous low-grade intraepithelial neoplasm (LGIN). METHODS: A training cohort of 201 patients with biopsy-confirmed esophageal squamous LGIN and underwent ESD at a tertiary medical center between January 2017 and July 2019 were included. Risk factors for histological upgrade were identified using the least absolute shrinkage and selection operator (LASSO) regression. A nomogram was then established. Internal validation was evaluated by discrimination, calibration plot, and decision-curve analysis. Another cohort of 48 patients were prospectively collected from July 2019 to June 2021 for external validation of the nomogram. RESULTS: The rate of histological upgrade was 34.8% (70/201) and 27.1% (13/48) in the training and validation sets, respectively. LASSO regression identified that tumor area (mm2 ) per biopsy, Lugol's staining pattern, background coloration, and the circumferential range of the lesion were significantly associated with histological upgrade. The final nomogram attained favorable prediction efficacy in the training cohort (area under the receiver operating curve [AUROC] 0.96, 95% confidence interval [CI] 0.94-0.98) and validation cohort (AUROC 0.92, 95% CI 0.79 -0.99). This model generated well-fitted calibration and clinical-decision curves in both cohorts. CONCLUSIONS: The nomogram may better guide clinical decision on whether performing EDS or follow-up for suspicious lesions in patients with biopsy-confirmed esophageal squamous LGIN.

NF-kappaB related abnormal hyper-expression of iNOS and NO correlates with the inflammation procedure in biliary atresia livers.

OBJECTIVE: To study the expression of inducible nitric oxide synthase (iNOS) and its related regulators in biliary atresia (BA) livers and exlpore their relationships with the inflammation pathway in BA livers. METHOD: The iNOS expression in livers of 38 cases of BA children, 15 cases of neonatal cholestasis (NC) children, and 18 cases of normal control were, respectively, examined and total nitric oxide (NO) metabolites concentration of all samples were calculated by a colorimetric method based on Griess reaction. The TdT-mediated dupt biotin nick end labeling (TUNEL) method was used to label the apoptotic bile duct epithelial cells and hepatocytes. The western blotting and immunohistochemistry methods to semi-quantitatively analyze the nuclear factor-kappaB (NF-kappaB) expression of each group were also used. RESULTS: The iNOS expression intensity and total NO metabolites concentration of BA group (0.30 +/- 0.08, 90.40 +/- 12.46 micromol/L) were significantly higher than those of NC and normal control groups, P < 0.01. Correlation analysis showed a strong positive correlation between the serum AST level (152.76 +/- 29.59 U/L) and total NO metabolites concentration in BA group. Compared with the NC (32.47 +/- 5.55) and normal control (20.72 +/- 5.63) groups, a significantly higher apoptosis rate of intrahepatic bile duct epithelial cells was found in BA group (54.00 +/- 11.67) that tightly correlated with the iNOS intensity (r = 0.99, P < 0.01). The NF-kappaB intensity of BA group was also significantly higher than that of NC and normal control groups and had a strong positive correlation with the iNOS intensity (r = 0.97, P < 0.01). CONCLUSION: The abnormal hyper-expression of iNOS may play an important role in mediating the inflammation procedure in BA livers. This change perhaps has some relationship with the high expression of NF-kappaB and NO. These regulators can up-regulate the apoptosis of bile duct epithelial cells in BA livers and cause the damage to liver tissues.

Reversal effect of thalidomide on established hepatic cirrhosis in rats via inhibition of nuclear factor-kappaB/inhibitor of nuclear factor-kappaB pathway.

BACKGROUND: Suppression of nuclear factor-kappaB (NF-kappaB)/inhibitor of nuclear factor-kappaB (IkappaB) signaling pathway is a potential property of thalidomide. This study was designed to investigate the effects of thalidomide on expressions of NF-kappaB, IkappaB and intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule (VCAM-1) in established rat liver cirrhosis. METHODS: Rat liver cirrhosis was achieved by IP injection of carbon tetrachloride (CCl4) three times weekly for 8 weeks. CCl4 was then discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Hydroxyproline (HYP) content in liver was detected by biochemical assay. NF-kappaBp65, ICAM-1, VCAM-1 and alpha-smooth muscle actin (alpha-SMA) protein in the liver, IkappaBalpha protein in cytoplasm and NF-kappaBp65 protein in nucleus and ICAM-1, VCAM-1 mRNA levels in the liver were studied using immunohistochemistry, Western blot, and reverse transcriptase polymerase chain reaction, respectively. RESULTS: Compared with the spontaneous recovery of cirrhosis, the histopathology of liver of rats given thalidomide was significantly improved. HYP content in liver, the expressions of ICAM-1, VCAM-1 mRNA and protein, NF-kappaBp65 and alpha-SMA protein were decreased significantly and IkappaBalpha protein in liver was elevated significantly in this group. CONCLUSIONS: Thalidomide may exert its effect on downregulation of NF-kappaB-induced adhesion molecules and activation of hepatic stellate cell via inhibition of degradation of IkappaB to reverse established rat hepatic cirrhosis.

Expression of NF-kappaB in rotavirus-induced damage to the liver and biliary tract in neonatal mice.

BACKGROUND: Biliary atresia, the etiology of which still remains unclear, occurs exclusively in newborns and most are infected with rotavirus. In this study, we aimed to investigate the histopathological patterns of different kinds of rotavirus in the liver and biliary tract of neonatal mice and the expression of NF-kappaB in the liver and biliary tract of infected mice. METHODS: Twenty-three adult mice (8 were male and 15 female) were divided into 8 breeding pairs, and each pair (1 male and 2 females) was housed in a cage in a laminar flow hood. Newborn mice, 24-48 hours old were randomly divided into A, B and C groups. The A and B groups were respectively inoculated with MMU18006 and SA11 rotavirus through the intraperitoneal route, while group C as blank control was only inoculated with culture medium. The liver was dissected after 5, 10, 15, 21 and 28 days; the weight of each mouse and the histopathological patterns in the liver were recorded. The expression of NF-kappaB in the liver and intrahepatic bile ducts was detected by immunohistochemical staining and the expression intensity was analyzed with a GT-2 imaging instrument. RESULTS: The average increase in weight of infected mice was significantly slower than that of the normal control, while the growth rate of group A (injected with MMU18006 rotavirus) was slower than that of group B (SA11 rotavirus). In infected mice, the acute and chronic inflammation of liver and intra- and extra-hepatic bile ducts was more significant in group A. Stenosis was found in most intrahepatic bile ducts, and sporadically in extrahepatic bile ducts. The expression of NF-kappaB in infected mice was dramatically higher than that of the normal control, while the expression in group A was higher than in group B. CONCLUSIONS: Significant damage to the liver and biliary tract of neonatal mice can be induced by inoculating MMU18006 rotavirus through the intraperitoneal route, which is very similar to the pathology of biliary atresia in the newborn human. Similar inoculation with SA11 rotavirus can only result in moderate impairment that disappears quickly. The difference of pathogenicity between the two rotaviruses may depend on their differing capacities to increase the expression of NF-kappaB in the liver and biliary tract.

[The role of protein kinase C-mediated phosphorylation of type III inositol 1, 4, 5-triphosphate receptor in cholecystokinin octapeptide induced calcium mobilization in gastric antral smooth muscle cells].

OBJECTIVE: To study the effects of sulfated cholecystokinin octapeptide (sCCK-8S) on intracellular calcium release and extracellular calcium influx in gastric antral smooth muscle cells (SMC) and the mechanism thereof. METHODS: (1) Longitudinal muscle (LM) and circular muscle (CM) strips of gastric antrum and pylorus were isolated from SD rats and suspended in a tissue chamber to record the contractile responses by polyphysiography. (2) Immunoprecipitation, electrophoresis, and immunoblotting were used to detect the phosphorylation of type III inositol 1, 4, 5-triphosphate receptor (InsP(3)R(3)) in the SMCs. (3) The responsiveness of gastric SMC to CCK-8S was examined by using fura-2-loaded microfluorimetric measurement of intracellular calcium concentration ([Ca(2+)]i). (4) The current of L-type calcium channels (ICaL) was recorded by using patch-clamp techniques. RESULTS: (1) Significant changes to CCK-8S were found in the mean contractile amplitude of the CM and frequency of LM of gastric antrum and could be suppressed by CCK-A receptor (CCK-AR) antagonist and ATPase inhibitors. (2) CCK-8S stimulation of SMC resulted in PKC-dependent phosphorylation of the InsP(3)R(3). (3) CCK-8S-evoked significant increase in [Ca(2+)]i [from (69 +/- 7) mol/L to (472 +/- 36) nmol/L, P < 0.01] could be suppressed by CCK-AR antagonist, ATPase inhibitors and protein kinase C (PKC) activator; whereas on condition that extracellular calcium was removed or L-type calcium inhibitor nifedipine was added a small but significant increase of [Ca(2+)]i could be still elicited by CCK-8S. (4) CCK-8S-intensified calcium current [from (-56 +/- 7) pA to (-89 +/- 6) pA, P < 0.01] could be apparently inhibited by respective administration of nifedipine, ATPase inhibitors, and calcium dependent chloride channel (I(Cl-Ca)) blocker (all P < 0.01). CONCLUSION: CCK-8S-evoked [Ca(2+)]i increase in gastric antral SMCs depends on the release of intracellular calcium stores, which is regulated by PKC mediated phosphorylation of InsP(3)R(3). The released intracellular calcium in turn activates the L-type voltage-dependent calcium channels (VDCC) through the activation of calcium dependent chloride channels, and ultimately results in the occurrence of contraction response of smooth muscles.

Effects of cholecystokinin-8 induced gastric dysmotility on bile regurgitation during stress and molecular mechanisms.

OBJECTIVE: To illustrate the existence of bile regurgitation under stress condition, and explore the possible effects and related mechanism of changes of plasma cholecystokinin octapeptide (CCK-8) and intragastric pH on stress-induced bile regurgitation in rats. METHODS: (1) Changes in plasma CCK-8 and gastric bile concentration were respectively measured by using radioimmunoassay (RIA) method while simultaneously calculating gastric ulcer index (UI) and intragastric pH; (2) Each isolated gastric strips were suspended in a tissue chamber to record the contractile responses by polyphysiograph; (3) The responsiveness of gastric smooth muscle cells (SMCs) to sulfated cholecystokinin octapeptide (CCK-8S) were examined using fura-2-loaded microfluorimetric measurement of intracellular calcium concentration ([Ca(2+)]i); (4) The current of L-type calcium channels (I(CaL)) of SMCs were recorded by patch clamp techniques. RESULTS: (1) Compared with the normal control group, plasma CCK-8 and gastric bile concentration significantly increased during stress (p<0.01) and both simultaneously reached the peak at the time point of 2 h after stress; UI and intragastric pH apparently increased (p<0.01); (2) Significant changes to CCK-8S were found in the mean contractile amplitude and frequency of circular muscle (CM) and longitudinal muscle (LM) of gastric antrum and pylorus; (3) CCK-8S-evoked significant increase in [Ca(2+)]i (p<0.01) could be suppressed by CCK-A receptor (CCK-AR) antagonist; whereas a small but significant increase was still elicited by CCK-8S under condition of the removal of extracellular calcium or by given nifidipine; (4) CCK-8S-intensified calcium current (I(CaL)) apparently inhibited by respective administration of nifidipine, Ca(2+)-ATPase inhibitors or calcium dependent chloride channel (I(Cl-Ca)) blocker (p<0.01). CONCLUSION: Gastric mucosal damage induced by bile regurgitation is closely connected with gastric antrum and pylorus dysmotility evoked by CCK-8 during the stress. CCK-8S-evoked [Ca(2+)]i increase in gastric antrum and pylorus SMC depends on the release of intracellular calcium stores which activates L-type voltage-dependent calcium channels (VDCC) through the activation of calcium dependent chloride channels.

Thalidomide prevents rat liver cirrhosis via inhibition of oxidative stress.

This study investigated the effect of thalidomide on oxidative stress in rat liver cirrhosis. The cirrhosis of rat was induced by intraperitoneal injection of carbon tetrachloride thrice weekly; meanwhile, thalidomide (10mg/kg or 100mg/kg) was given daily by intragastric administration for 8 weeks. The content of oxidative stress parameters, including superoxide dismutase, glutathione peroxidase, and malondialdehyde, in the liver was detected by biochemical assay. Immunohistochemistry revealed alpha-smooth muscle actin (alpha-SMA), desmin, and tissue inhibitor of metalloproteinase-1 (TIMP-1) protein in the liver. Nuclear factor kappa B p65 (NF-kappaBp65) protein in nucleus and transforming growth factor beta1 (TGF-beta1) protein in cytoplasm were detected by Western blot. NF-kappaBp65, TGF-beta1, and TIMP-1 mRNA levels in the liver were studied using reverse transcriptase polymerase chain reaction. Liver histopathology was significantly improved in rats given high doses of thalidomide. The content of oxidative stress parameters and the expressions of NF-kappaBp65, TGF-beta1 and TIMP-1 protein, and mRNA were significantly decreased in these animals. The expressions of alpha-SMA and Desmin protein were also significantly decreased in them. Thalidomide might exert an effect on the inhibition of oxidative stress via downregulation of NF-kappaB signaling pathway to prevent the progression of liver cirrhosis.

[The effect and mechanism of cholecystokinin octapeptide induced-gastric dysmotility on bile regurgitation during stress].

OBJECTIVE: To illustrate the existence of bile regurgitation under stress condition, and explore the possible effects and related mechanism of changes of cholecystokinin octapeptide (CCK-8) on stress-induced bile regurgitation in rats. METHODS: (1) Changes in plasma CCK-8 and gastric bile concentration were measured by using radioimmunoassay while simultaneously calculating gastric ulcer index and intragastric pH; (2) Each isolated gastric strips were suspended in a tissue chamber to record the contractile responses by polyphysiograph; (3) The responsiveness of gastric smooth muscle cells (SMCs) to sulfated cholecystokinin octapeptide (CCK-8S) were examined using fura-2-loaded microfluorimetric measurement of intracellular calcium concentration ([Ca(2+)] i); (4) The current of L-type calcium channels (I(CaL)) of SMCs were recorded by patch-clamp techniques. RESULTS: (1) Compared with the normal control, plasma CCK-8 [from (2.23 +/- 0.88) pmol/L to (10.80 +/- 3.82) pmol/L] and gastric bile concentration [from (37.93 +/- 23.76) micromol/L to (1316.00 +/- 197.36) micromol/L] significantly increased during the stress (P < 0.01) and both simultaneously reached the peak at the time point of 2 h after stress; ulcer index (from 0.62 +/- 0.23 to 32.01 +/- 16.11) and intragastric pH (from 1.06 +/- 1.20 to 5.29 +/- 1.25) apparently increased (P < 0.01); (2) Significant changes to CCK-8S were found in the mean contractile amplitude and frequency of circular muscle and longitudinal muscle of gastric antrum and pylorus; (3) CCK-8S-evoked significant increase in [Ca(2+)] i [from (65.8 +/- 7.4) nmol/L to (472.1 +/- 35.6) nmol/L, P < 0.01] could be suppressed by CCK-A receptor antagonist; whereas a small but significant increases were still elicited by CCK-8S under condition of the removal of extracellular calcium; (4) CCK-8S-intensified calcium current I(Ca-L) [from (-56.42 +/- 6.57) pA to (-88.54 +/- 5.71) pA, P < 0.01)] apparently inhibited by respective administration of nifedipine, Ca(2+)-ATPase inhibitors or calcium dependent chloride channel blocker (P < 0.01). CONCLUSIONS: Gastric mucosal damage induced by bile regurgitation is closely connected with gastric antrum and pylorus dysmotility evoked by CCK-8 during the stress. CCK-8S-evoked [Ca(2+)] i increase in gastric antrum and pylorus SMC depends on the release of intracellular calcium stores which activates L-type voltage-dependent calcium channels through the activation of calcium dependent chloride channels.

A severe course of Cronkhite-Canada syndrome and the review of clinical features and therapy in 49 Chinese patients.

We describe a severe case of Cronkhite-Canada syndrome and review the clinical features and therapy in 49 Chinese patients. A 67-year-old man who underwent severe chronic diarrhea had typical clinical manifestations of hyperpigmentation, hair loss, and dystrophic changes in the fingernails. Although sufficient nutrition support and other therapies reported in the literature were provided, the patient died of systemic failure one year later. Cronkhite-Canada syndrome is characterized by generalized gastrointestinal polyps associated with hyperpigmentation, hair loss, and onycholysis. Anemia, positive stool occult blood, serum electrolyte disturbances, and low serum proteins are the main clinical features of patients with Cronkhite-Canada syndrome. Most patients were diagnosed by esophagogastroduodenoscopy and/or colonoscopy, and polyps were found in the entire alimentary tract, except the notable exception of the esophagus. The polyp-like samples of mucosa, hyperplasia, and adenoma were characterized by acute/chronic inflammation. Four cases were complicated with cancer. The treatment of Cronkhite-Canada syndrome includes symptomatic and support therapy, administration of corticosteroids, antibiotics and acid inhibitors, therapeutic endoscopy, and surgery. While the mortality rate was reported as 47.3% (9/19), some patients may live a long life with controlled symptoms.

Mechanisms of cholecystokinin-induced calcium mobilization in gastric antral interstitial cells of Cajal.

AIM: To investigate the effect of sulfated cholecystokinin-8 (CCK-8S) on calcium mobilization in cultured murine gastric antral interstitial cells of Cajal (ICC) and its possible mechanisms. METHODS: ICC were isolated from the gastric antrum of mice and cultured. Immunofluorescence staining with a monoclonal antibody for c-Kit was used to identify ICC. The responsiveness of ICC to CCK-8S was measured using Fluo-3/AM based digital microfluorimetric measurement of intracellular Ca(2+) concentration ([Ca(2+)]i). A confocal laser scanning microscope was used to monitor [Ca(2+)]i changes. The selective CCK(1) receptor antagonist lorglumide, the intracellular Ca(2+)-ATPase inhibitor thapsigargin, the type III inositol 1,4,5-triphosphate (InsP(3)) receptor blocker xestospongin C and the L-type voltage-operated Ca(2+) channel inhibitor nifedipine were used to examine the mechanisms of [Ca(2+)]i elevation caused by CCK-8S. Immunoprecipitation and Western blotting were used to determine the regulatory effect of PKC on phosphorylation of type III InsP(3) receptor (InsP(3)R3) in ICC. Protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) and inhibitor chelerythrine were used to assess the role of PKC in the CCK-8S-evoked [Ca(2+)]i increment of ICC. RESULTS: ICC were successfully isolated from the gastric antrum of mice and cultured. Cultured ICC were identified by immunofluorescence staining. When given 80 nmol/L or more than 80 nmol/L CCK-8S, the [Ca(2+)]i in ICC increased and 100 nmol/L CCK-8S significantly increased the mean [Ca(2+)]i by 59.30% ± 4.85% (P < 0.01). Pretreatment of ICC with 5 µmol/L lorglumide inhibited 100 nmol/L CCK-8S-induced [Ca(2+)]i increment from 59.30% ± 4.85% to 14.97% ± 9.05% (P < 0.01), suggesting a CCK(1)R-mediated event. Emptying of intracellular calcium stores by thapsigargin (5 µmol/L) prevented CCK-8S (100 nmol/L) from inducing a [Ca(2+)]i increase. Moreover, pretreatment with xestospongin C (1 µmol/L) could also abolish the CCK-8S-induced effect, indicating that Ca(2+) release from InsP(3)R-operated stores appeared to be a major mechanism responsible for CCK-8S-induced calcium mobilization in ICC. On the other hand, by removing extracellular calcium or blocking the L-type voltage-operated calcium channel with nifedipine, a smaller but significant rise in the [Ca(2+)]i could be still elicited by CCK-8S. These data suggest that the [Ca(2+)]i release is not stimulated or activated by the influx of extracellular Ca(2+) in ICC, but the influx of extracellular Ca(2+) can facilitate the [Ca(2+)]i increase evoked by CCK-8S. CCK-8S increased the phosphorylation of InsP(3)R3, which could be prevented by chelerythrine. Pretreatment with lorglumide (5 µmol/L) could significantly reduce the CCK-8S intensified phosphorylation of InsP(3)R3. In the positive control group, treatment of cells with PMA also resulted in an enhanced phosphorylation of InsP(3)R3. Pretreatment with various concentrations of PMA (10 nmol/L-10 µmol/L) apparently inhibited the effect of CCK-8S and the effect of 100 nmol/L PMA was most obvious. Likewise, the effect of CCK-8S was augmented by the pretreatment with chelerythrine (10 nmol/L-10 µmol/L) and 100 nmol/L chelerythrine exhibited the maximum effect. CONCLUSION: CCK-8S increases [Ca(2+)]i in ICC via the CCK(1) receptor. This effect depends on the release of InsP(3)R-operated Ca(2+) stores, which is negatively regulated by PKC-mediated phosphorylation of InsP(3)R3.

Signal transduction pathways mediating CCK-8S-induced gastric antral smooth muscle contraction.

AIM: To investigate the functional and molecular mechanisms by which sulfated cholecystokinin octapeptide (CCK-8S) regulates calcium mobilization in gastric antral smooth muscle cells (SMCs) of rats. METHODS: Isotonic contraction of antral strips was recorded using a polyphysiograph. Immunoprecipitation was used to determine the regulatory effect of protein kinase C (PKC) on regulating the phosphorylation of the type III inositol 1,4,5-triphosphate receptor (InsP(3)R3) in gastric SMCs. Alterations in the intracellular calcium ([Ca(2+)](i)) concentration were assayed using fura-2/AM-loaded microspectrofluorometry, and the L-type calcium current (I(Ca-L)) was recorded by patch-clamp techniques. RESULTS: CCK-8S (5 x 10(-8) mol/l) significantly increased the mean contractile amplitude of circular muscle by 61.85 +/- 12.67% and the frequency of longitudinal muscle by 57.91 +/- 15.70% in gastric antral strips, which were suppressed by dexloxiglumide or thapsigargin (TG) and BAPTA-AM (BA). Treatment with chelerythrine (5 x 10(-8) mmol/l) significantly inhibited the CCK-8S-increased phosphorylation of InsP(3)R3 in SMCs. The amplitudes of the CCK-8S-triggered [Ca(2+)](i) concentration oscillations were reduced in a dose-dependent manner when the SMCs were pretreated with increasing concentrations of PMA (from 10(-8) to 10(-5) mol/l). On removal of extracellular calcium or blocking I(Ca-L) by nifedipine, a smaller but significant rise in the [Ca(2+)](i) concentration was still elicited by CCK-8S. When [Ca(2+)](i) was depleted by the administration of 10(-5) mol/l TG and 10(-5) mol/l BA or blocked by the calcium-dependent chloride current (I(Cl-Ca)) by giving 5 x 10(-6) mol/l niflumic acid, the CCK-8S-intensified I(Ca-L) (from -56.42 +/- 6.57 to -88.54 +/- 5.71 pA) was apparently inhibited by 90.34 +/- 4.71% and 82.59 +/- 4.24%. CONCLUSIONS: These results demonstrate that the CCK-8S-evoked [Ca(2+)](i) concentration increase in gastric antral SMCs depends on the release of [Ca(2+)](i) stores which are negatively regulated by PKC-mediated phosphorylation of InsP(3)R3. Released calcium in turn activates I(Ca-L) through the activation of I(Cl-Ca), ultimately resulting in the contraction of the gastric smooth muscle.