Addison's disease caused by adrenal tuberculosis may lead to misdiagnosis of major depressive disorder: A case report

BACKGROUND

Addison's disease (AD) is a rare but potentially fatal disease in Western countries, which can easily be misdiagnosed at an early stage. Severe adrenal tuberculosis (TB) may lead to depression in patients.

CASE SUMMARY

We report a case of primary adrenal insufficiency secondary to adrenal TB with TB in the lungs and skin in a 48-year-old woman. The patient was misdiagnosed with depression because of her depressed mood. She had hyperpigmentation of the skin, nails, mouth, and lips. The final diagnosis was adrenal TB that resulted in the insufficient secretion of adrenocortical hormone. Adrenocortical hormone test, skin biopsy, T cell spot test of TB, and adrenal computed tomography scan were used to confirm the diagnosis. The patient's condition improved after hormone replacement therapy and TB treatment.

CONCLUSION

Given the current status of TB in high-burden countries, outpatient doctors should be aware of and pay attention to TB and understand the early symptoms of AD.

Sciatic hernia led to strangulated ileum and ipsilateral ovary: A case report and review of literature

Sciatic hernia is one of the rarely pelvic floor hernias. We report a 45-year-old woman who presented with acute crampy pain of hypogastrium which radiated down the back of the left thigh and found a mass in her left buttock area which is about fist size with local pain, so she had to force to bow position when walking. She was also associated with definite gastro-intestinal symptoms. Computed tomography (CT) of the pelvis and abdomen demonstrated the herniation of an ileal loop through the sciatic foramen on the left side. The diagnosis and management of this case are herein described and previous publications on sciatic hernias are reviewed.

[Death-related risk factors analysis of surgical treatment of myocardial infarction combined with ventricular septal rupture]

Objective: To in vestigate the death-related risk factors of surgical treatment of myocardial infarction (MI) combined with ventricular septal rupture (VSR). Methods: The clinical data of patients (68 cases) with ventricular septal rupture after myocardial infarction (PI-VSR) from January 2008 to December 2020 in Beijing Anzhen Hospital were retrospectively selected and analyzed. We followed up the surviving patients and divided them into the survival group and the death group according to the perioperative and follow-up results. The univariate analysis was performed on various indicators, and the Cox regression analysis was used to analyze the risk factors related to postoperative death. Results: A total of 68 patients (42 were male and 26 were female, with age 44-82 (64.3±8.2) years after surgical treatment of myocardial infarction combined with ventricular septal rupture were enrolled, 9 patients died during the perioperative period, 59 surviving patients were followed up for 0.1-10.5 years(mean, 4 years), and 7 deaths during follow-up. Based on this, 52 patients were selected as the survival group while 16 patients as the death group. The results of univariate analysis showed that age, VSR to operation time less than 7 days, killip grade ≥ grade 3, cardiogenic shock, preoperative use of IABP, emergent surgery were related to postoperative death. The factors with P<0.2 factors in univariate analysis were selected into the multivariate Cox regression analysis. Age ([OR=1.110(1.012-1.217), P=0.026], platelet count [OR=0.990(0.981-0.999), P=0.031], D dimer (OR=1.002[1.001-1.003], P=0.003), cardiogenic shock (OR=6.084[1.729-21.405], P=0.005) were independent risk factors for postoperative death. All patients were followed up, the survival rate of 2-year, 4-year, 6-year, 8-year, and 10-year was 77.5%, 77.5%, 71.0%, 71.0%, and 71.0%, respectively. Conclusions: Age, platelet count, D-dimer, and cardiogenic shock are risk factors for death after surgical treatment of myocardial infarction combined with ventricular septal rupture. Surgery is an effective method for the treatment of myocardial infarction combined with ventricular septal rupture. Long-term prognosis of the surviving patients during perioperative are relatively better.

[Surgical treatment strategies for Siewert type II adenocarcinoma of the esophagogastric junction]

The incidence of adenocarcinoma of the esophagogastric junction (AEG) continues to rise. While many treatment modalities are available, surgery is still the basis of comprehensive treatment of AEG. Siewert type II AEG, is more controversial than the other two types in terms of lymph node metastasis, surgical approach, extent of resection, and digestive tract reconstruction. When the distance of the superior tumor margin is more than 3 cm proximal to the EGJ line is more than 3 cm, thorough mediastinal lymph node dissection should be performed through thoracic approach. Total gastrectomy is the treatment of choice for Siewert type II tumors. When the tumor stage is in an early stage, the length of the tumor is ≤4 cm, and esophageal involvement is less than 3 cm, transthoracic esophagectomy plus proximal gastrectomy is feasible. The digestive tract reconstruction can be based on the experience of the operator and patient's choice of conditions.

[Safety and feasibility of indocyanine green injection through accessory incision in laparoscopic right hemicolectomy]

Objective: To explore the safety and feasibility of indocyanine green (ICG) injection through accessory incision in laparoscopic right hemicolectomy. Methods: A descriptive case series study was carried out. Clinicopathological data of 29 patients with colon cancer undergoing right hemicolectomy at Department of General Surgery, Guangdong Provincial People's Hospital were retrospectively analyzed. All the patients received ICG injection through accessory incision at the beginning of operation. Results: Among 29 patients, 13 were male and 16 were female with a mean age of (60.8±7.7) years and mean body mass index of (24.3±2.8) kg/m(2); 3 were stage I, 19 were stage II, 7 were stage III. Pericolic, intermediate and main lymph nodes could be detected under near infrared fluorescence imaging (NIRFI) in all the cases. No.6 lymph nodes were observed in 3 cases, while no lymph nodes around superior mesenteric vein (SMV) were found. The average number of fluorescent lymph node was 14.2±6.1. The average developing time of fluorescence was (36.2±3.7) minutes. The average number of harvested lymph nodes was 22.4±8.2. There was no extravasation of imaging agent during the operation, and there were no intraoperative complications such as allergies, massive abdominal bleeding, peripheral organ damage, etc. Operative time was (113.1±10.7) minutes, blood loss during operation was (22.4±3.9) ml, ambulatory time was (1.2±0.4) days, time to the first flatus was (1.7±0.7) days, time to the first fluid diet was (0.7±0.4) days, and postoperative hospital stay was (5.8±1.5) days. No operation-associated complications such as anastomotic bleeding, anastomotic leakage, peritoneal bleeding, peritoneal infection, incision infection occurred after operation. Conclusion: ICG injection through accessory incision in laparoscopic right hemicolectomy is safe and feasible.

[Feasibility and safety of the medial approach "four-step method" in the laparoscopic mobilization of splenic flexure]

Objective: To investigate the feasibility and safety of the medial approach "four-step method" in the laparoscopic mobilization of splenic flexure. Methods: A retrospective cohort study was performed. Clinical data of 157 colorectal cancer patients undergoing the medial approach "four-step method" in the laparoscopic mobilization of splenic flexure at Gastrointestinal Surgical Department of Guangdong Provincial People's Hospital from July 2015 to June 2018 were retrospectively analyzed. Of 157 cases, 17 were transverse colon cancer, 94 were descending colon cancer, 25 were sigmoid cancer and 21 were rectal cancer; 89 were male and 68 were female; mean age was (61.8±10.3) years and mean body mass index was (23.2±3.7) kg/m(2). The medial approach "four-step method" in the laparoscopic mobilization of splenic flexure was performed as follows: (1) The root vessels were treated with the "provocation" technique to expand the Toldt's gap. This expansion was extended from the lateral side to the peritoneum reflex of left colonic sulcus, from the caudal side to the posterior rectal space, and from the cephalad side to the lower edge of pancreas. (2) The left colonic sulcus was mobilized, converging with the posterior Toldt's gap. Mobilization was carried out from cephalad side to descending colon flexure, freeing and cutting phrenicocolic ligament and splenocolic ligament, and from caudal side to peritoneal reflex. (3) Gastrocolic ligament was moblized. Whether to enter the great curvature of stomach omentum arch when the gastrocolic ligament was cut, that was, whether to clean the fourth group of lymph nodes, should be according to the tumor site and whether serosal layer was invaded. (4) Transverse mesocolon was moblized and transected at the lower edge of the pancreatic surface, merging with the posterior Toldt's gap, and from lateral side to lower edge of the pancreatic body, merging with the lateral left paracolonic sulcus. Safety and short-term clinical efficacy of this surgical procedure was summarized. Results: All the patients completed this procedure. During operation, 3 cases were complicated with organ injury, including 1 case of colon injury, 1 case of spleen injury and 1 case of pancreas injury. No operative death and conversion to open surgery was found. The average operation time was (147.5±35.1) minutes, the average intra-operative blood loss was (40.8±32.7) ml and the average number of harvested lymph node was (16.1±5.8), including (4.0±2.3) of positive lymph nodes. The first exhaust time after surgery was (41.3±20.6) hours, the fluid intake time was (1.5±1.3) days, the postoperative hospital stay was (5.2±2.3) days. Eight (5.1%) cases developed postoperative complications, and all were improved and discharged after conservative treatments. According to the TNM classification system, postoperative pathology revealed that 31 patients were stage I, 51 were stage II, 53 were stage III, 22 were stage IV. Conclusion: The medial approach "four-step method" is safe and feasible, which can effectively decrease the operation difficulty of the laparoscopic mobilization of the splenic flexure.

Bile acids promote gastric intestinal metaplasia by upregulating CDX2 and MUC2 expression via the FXR/NF-κB signalling pathway

Bile acids serve a critical role in the induction of gastric intestinal metaplasia (IM) and gastric carcinogenesis. The present study investigated the effects of bile acids on the induction of gastric IM formation. The results demonstrated that the expression levels of caudal-related homeobox transcription factor 2 (CDX2), mucin 2 (MUC2) and farnesoid X receptor (FXR) were increased in vitro and in vivo following treatment with bile acids, and CDX2 transcriptionally activated MUC2 expression. Furthermore, knockdown of FXR attenuated bile acid-enhanced CDX2 promoter activity and protein expression. Conversely, the FXR agonist GW4064 synergistically enhanced bile acid-induced CDX2 promoter activity. Bile acid treatment led to an increase in nuclear factor (NF)-κB activity and protein expression. Treatment with GW4064 or the FXR antagonist Z-guggulsterone enhanced or attenuated bile acid-induced NF-κB activity, respectively. In addition, quantitative chromatin immunoprecipitation confirmed that bile acids led to enhanced binding of p50 to the CDX2 promoter, whereas this effect was not observed for p65. Treatment with GW4064 or Z-guggulsterone enhanced and attenuated the binding activity of p50 to the CDX2 promoter, respectively. These results indicated that bile acids may activate the FXR/NF-κB signalling pathway, thereby upregulating CDX2 and MUC2 expression in normal gastric epithelial cells.

[Short-term clinical safety and efficacy of No-touch great saphenous vein harvesting technique for off-pump coronary artery bypass grafting]

Objective: To evaluated early clinical outcomes of saphenous vein grafts harvested with a No-touch technique in off-pump coronary artery bypass graft (OPCABG) surgery. Methods: A total of 124 patients with three-vessel disease undergoing OPCABG by No-touch technique between June and November 2017 in Beijing An Zhen Hospital were respectively reviewed. Results: The average age of patients was (60.7±10.3) years, and 80 cases (64.5%) were male, with the average body mass index (BMI)of (25.4±2.5) kg/m(2,) the mean preoperative left ventricular ejection fraction (LVEF) of (58.0±7.0%). The operative time was (4.0±0.4) hours, and 16 cases (12.9%) were harvested for whole vein grafts. The number of vein grafts and venous anastomoses was 144 and 284, respectively. There were 16 cases of single bridge NTSVG-LAD, 4 cases of single bridge NTSVG-D, 99 cases of sequential bridge NTSVG-OM-PDA, 5 cases of sequential bridge NTSVG-OM-PLV, 4 cases of sequential bridge NTSVG-OM-RCA, 16 cases of sequential bridge NTSVG-D-OM-PDA. The mean flow volume of No-touch vein grafts was (51.9±2.4) ml/min. There was no death case in hospital. Postoperative re-exploration for hemorrhage of anastomosis happened in 1 case (0.8%), which was caused by pericardial tamponade due to insufficiency of hemostasis in internal mammary bed. There were 1 case of bad wound healing of lower extremity incision (0.8%). A total of 124 cases were followed up after operation, and the follow-up rate was 100%. There was one all-cause death (0.8%) 27 days after the operation. Conclusion: The short-term clinical observation of the application of No-touch great saphenous vein harvesting technique for OPCABG is safe and effective.

Felodipine inhibits ox-LDL-induced reactive oxygen species production and inflammation in human umbilical vein endothelial cells

Oxidative stress and inflammation are involved in the pathogenesis of atherosclerosis. Calcium channel blockers (CCBs) inhibit the development of atherosclerosis, although the underlying molecular basis has not been completely elucidated. The present study was designed to investigate the effects of felodipine, a CCB, on inflammation and oxidative stress in human umbilical vein endothelial cells (HUVECs) and to examine the underlying mechanisms of action. Oxidized low‑density lipoprotein (ox‑LDL) was used to induce an inflammatory response in HUVECs. The effects of felodipine were investigated by measuring the content of nitric oxide (NO) and reactive oxygen species (ROS), the mRNA and protein levels of intercellular adhesion molecule 1 (ICAM‑1) and vascular cell adhesion protein 1 (VCAM‑1), and the mRNA levels of endothelial NO synthase (eNOS) and inducible NO synthase (iNOS), in addition to the adhesion ability of U937 cells to HUVECs. ROS and NO levels were significantly increased in HUVECs following 24‑h treatment with 25 mg/l ox‑LDL (P<0.01). The increase in ROS was reversed by treatment with felodipine. In addition, NO levels were increased following treatment with 1 µmol/l felodipine (P<0.05). The mRNA expression of ICAM‑1, VCAM‑1, eNOS and iNOS was increased (P<0.05). Administration of 0.1 µM felodipine significantly decreased the expression of ICAM‑1, VCAM‑1, and iNOS (P<0.05). The number of U937 cells adhered to ox‑LDL‑treated HUVECs was significantly increased compared with control, which was reversed by felodipine (0.1 µM). In conclusion, felodipine was demonstrated to inhibit oxidative stress and inflammatory responses, suggesting that it may be used to treat atherosclerosis.

Modification of the hTERT promoter by heat shock elements enhances the efficiency and specificity of cancer targeted gene therapy

PURPOSE

One of the current challenges facing cancer gene therapy is the tumour-specific targeting of therapeutic genes. Effective targeting in gene therapy requires accurate spatial and temporal control of gene expression. To develop a sufficient and accurate tumour-targeting method for cancer gene therapy, we have investigated the use of hyperthermia to control the expression of a transgene under the control of the human telomerase reverse transcriptase (hTERT) promoter and eight heat shock elements (8HSEs).

MATERIALS AND METHODS

Luciferase reporters were constructed by inserting eight HSEs and the hTERT promoter (8HSEs-hTERTp) upstream of the pGL4.20 vector luciferase gene. The luciferase activity of the hTERT promoter and 8HSEs-hTERT promoter were then compared in the presence and absence of heat. The differences in luciferase activity were analysed using dual luciferase assays in SW480 (high hTERT expression), MKN28 and MRC-5 cells (low hTERT expression). The luciferase activity of the Hsp70B promoter was also compared to the 8HSEs-hTERT promoter in the above listed cell lines. Lentiviral vector and heat-induced expression of EGFP expression under the control of the 8HSEs-hTERT promoter in cultured cells and mouse tumour xenografts was measured by reverse transcription polymerase (RT-PCR), Western blot and immunofluorescence assays.

RESULTS

hTERT promoter activity was higher in SW480 cells than in MKN28 or MRC-5 cells. At 43 °C, the luciferase activity of the 8HSEs-hTERT promoter was significantly increased in SW480 cells, but not in MKN28 or MRC-5 cells. Importantly, the differences in luciferase activity were much more obvious in both high (SW480) and low (MKN28 and MRC-5) hTERT expressing cells when the activity of the 8HSEs-hTERT promoter was compared to the Hsp70B promoter. Moreover, under the control of 8HSEs-hTERT promoter in vitro and in vivo, EGFP expression was obviously increased by heat treatment in SW480 cells but not in MKN28 or MRC-5 cells, nor was expression increased under normal temperature conditions.

CONCLUSIONS

The hTERT promoter is a potentially powerful tumour-specific promoter and gene therapy tool for cancer treatment. Incorporating heat-inducible therapeutic elements (8HSEs) into the hTERT promoter may enhance the efficiency and specificity of cancer targeting gene therapy under hyperthermic clinical conditions.

Overexpression of caudal-related homeobox transcription factor 2 inhibits the growth of transplanted colorectal tumors in nude mice

Caudal-related homeobox transcription factor 2 (CDX2) is a transcription factor, which is specifically expressed in the adult intestine. It is essential for the development and homeostasis of the intestinal epithelium and its functions as a tumor suppressor have been demonstrated in the adult colon. The present study aimed to examine the inhibitory effects of the overexpression of CDX2 on subcutaneously-transplanted tumors, derived from LoVo colon cancer cells, in nude mice, and to provide experimental evidence for the biotherapy of colon cancer. A pEGFP-C1-CDX2 eukaryotic expression vector was transfected into the LoVo cells via lipofection, and LoVo cells stably-expressing CDX2 (pEGFP-C1-CDX2 cells) were obtained using G418 selection. A nude mouse subcutaneously-transplanted tumor model was established by inoculating the nude mice with the pEGFP-C1-CDX2 cells, and the effects of overexpression of CDX2 on transplanted tumor growth in the LoVo cells were observed. Western blotting results demonstrated that the protein expression of CDX2 in the LoVo cells was higher in the pEGFP-C1-CDX2 cell group, compared with that in the pEGFP-C1 cell group and the untreated cell group. At 20 days post-inoculation with either pEGFP-C1-CDX2 or pEGFP-C1, the transplanted tumor masses were significantly lower in the pEGFP-C1-CDX2 group, compared with those in the pEGFP-C1 and untreated groups. Immunohistochemistry revealed that the expression levels of CDX2 and matrix metalloproteinase-2 (MMP-2) were detected in each group, and the protein expression of CDX2 was increased in the tumor tissues from the nude mice in the pEGFP-C1-CDX2 group. However the expression of MMP-2 was downregulated in the tumor tissues of the nude mice in the pEGFP-C1-CDX2 group. Taken together, these data suggested that pEGFP-C1-CDX2 cells exhibited suppressed tumor growth in vivo. Overexpression of CDX2 was observed in transplanted tumors in the pEGFP-C1-CDX2 group, and the gene expression of MMP-2 was reduced. These results indicate that CDX2 inhibited the growth of colorectal tumor cells, possibly by downregulating the gene expression.

Recombinant lentivirus with enhanced expression of caudal-related homeobox protein 2 inhibits human colorectal cancer cell proliferation in vitro

Caudal-related homeobox protein 2 (CDX2), a tumor suppressor in the adult colon, is overexpressed under a non-cancer specific cytomegalovirus promoter in certain tumor cells; furthermore, non-specific expression of CDX2 may result in aberrant side effects in normal cells. The human telomerase reverse transcriptase (hTERT) promoter is active in the majority of cancer cells but not in normal cells. Hypoxia is a key feature of solid tumors, and targeted genes may be significantly upregulated by five copies of hypoxia-response elements (HREs) under hypoxic conditions. However, the effect of CDX2 overexpression, as controlled by five copies of HREs and the hTERT promoter, on human colorectal cancer (CRC) cell proliferation in vitro remains to be fully elucidated. In the current study, a recombinant lentivirus containing the CDX2 gene under the control of five HREs and the hTERT promoter was generated. An immunofluorescence assay was used to detect CDX2 expression by the 5HhC lentivirus, whereas an MTT assay was used to detect the effects of CoCl₂ on the viability of LoVo cells. Western blot analysis was conducted in order to determine the relative ratios of recombinant CDX2 protein to the internal control β-actin, following 5HhC/LoVo cell culture under normoxic and hypoxic conditions (100, 200, 300, 400 or 500 µmol/l CoCl₂) for 24 h, then for 12, 24 or 36 h with the optimal concentration (300 µmol/l) of CoCl₂. Reverse transcription polymerase chain reaction analysis was used to determine the transcription of recombinant CDX2 mRNA following culture of 5HhC/LoVo cells under normoxic or hypoxic conditions. Finally, a cloning assay was used to detect the proliferative ability of 5HhC/LoVo and 5Hh cells. High CDX2 expression was observed in hTERT-positive LoVo cells under hypoxic conditions, an effect which was mimicked by treatment with CoCl₂ to inhibit LoVo cell proliferation in vitro. High expression of CDX2 therefore provides a promising strategy for the development of novel targeted treatments and gene therapy for CRC.

[Label-free monitoring 5-FU induced SW 620 cells apoptosis using FTIR microspectroscopy]

The aim of the present study was to evaluate Fourier transform infrared spectroscopy (FTIR) monitoring of biochemical changes in apoptosis cells. Different concentrations of 5-fluorouracil (5-FU) treated colon cancer cell lines SW620 were used to determine the optimum concentration of 5-FU IC50 by means of MTT assay. Cell starvation and 5-Fu synergistic cell cycle arrest was in G1 and S phase. FTIR combined with flow cytometry was applied to analysis of SW 620 cells and SW620 cells treated with 5-FU for 12h, 24h (early apoptosis) and 48 h (late apoptosis) respectively. The peak position and the intensity of all bands were measured and comparison was made between the SW620 and apoptotic SW620 cells. Apoptosis cells have following characteristics compared with SW620 cells (1) The band at 1 740 cm-1 is an C=O stretching vibration. Changes in these bands can reflect lipid changes, and relative peak intensity ratio 11740/11460 significantly increased (p<0. 05), indicating that the relative contents of lipid in apoptosis cells increased. (2) The band at the 1 410 cm-1 peak represents that C-H stretching related was increased to amino acid residues and shifted to higher wave numbers compared to other groups. I1410o/I 460 at early and late death phase was significantly increased, which suggests that the relative contents of amino acid residues in apoptosis cells increased (p <0. 05). New vibrational bands at 1 120 cm-1 appeared at 24 h and increased at 48 h compared with other groups. The 1 120 cm-1 absorption band is mainly due to ser, serine and threonine C-O(H) stretching vibration, and I1120/I 1460 significantly increased (p<0. 05), indicating that the relative quantity of amino acid residues in apoptosis cells increased due to that DNA unwinds the double helix. (3) 1 240 cm-1 is mainly due to the asymmetric stretching modes of phosphodiester groups shifting to higher wave number, illustrating that nucleic acid conformation was changed in apoptosis cells. (4) The band 1 040 cm-1 associated with polysaccharide appeared at 24 and 48 h, meanwhile shifted to higher wave number, suggesting that polysaccharide decreased in late apoptotic cells, and I 1040/I1400 increased at late stage apoptosis, indicating that the relative content of polysaccharide in apoptosis cells increased. The authors' results suggest that FTIR applied to monitoring SW620 cells apoptosis may be as a potential diagnostic tool for cancer chemotherapy monitoring.

Affinity peptide developed by phage display selection for targeting gastric cancer

AIM: To develop an affinity peptide that binds to gastric cancer used for the detection of early gastric cancer.

METHODS: A peptide screen was performed by biopanning the PhD-12 phage display library, clearing non-specific binders against tumor-adjacent normal appearing gastric mucosa and obtaining selective binding against freshly harvested gastric cancer tissues. Tumor-targeted binding of selected peptides was confirmed by bound phage counts, enzyme-linked immunosorbent assay, competitive inhibition, fluorescence microscopy and semi-quantitative analysis on immunohistochemistry using different types of cancer tissues.

RESULTS: Approximately 92.8% of the non-specific phage clones were subtracted from the original phage library after two rounds of biopanning against normal- appearing gastric mucosa. After the third round of positive screening, the peptide sequence AADNAKTKSFPV (AAD) appeared in 25% (12/48) of the analyzed phages. For the control peptide, these values were 6.8 ± 2.3, 5.1 ± 1.7, 3.5 ± 2.1, 4.6 ± 1.9 and 1.1 ± 0.5, respectively. The values for AAD peptide were statistically significant (P < 0.01) for gastric cancer as compared with other histological classifications and control peptide.

CONCLUSION: A novel peptide is discovered to have a specific binding activity to gastric cancer, and can be used to distinguish neoplastic from normal gastric mucosa, demonstrating the potential for early cancer detection on endoscopy.

Role of transforming growth factor-beta signaling pathway in pathogenesis of benign biliary stricture

AIM: To characterize the expression of members of the transforming growth factor-beta (TGF-β)/Smad/connective tissue growth factor (CTGF) signaling pathway in the tissue of benign biliary stricture, and to investigate the effect of TGF-β signaling pathway in the pathogenesis of benign biliary stricture.

METHODS: Paraffin embedded materials from 23 cases of benign biliary stricture were analyzed for members of the TGF-β/Smad/CTGF signaling pathway. TGF-β₁, TβRI, TβRII, Smad4, Smad7 and CTGF protein were detected by immunohistochemical strepto-advidinbiotin complex method, and CTGF mRNA was evaluated by hybridization in situ, while 6 cases of normal bile duct served as controls. The percentages of positive cells were counted. The correlation between TGF-β₁, Smad4 and CTGF was analyzed.

RESULTS: The positive expression ratios of TGF-β₁, TβRI, TβRII, Smad4, CTGF and CTGF mRNA in 23 cases with benign biliary stricture were 91.3%, 82.6%, 87.0%, 78.3%, 82.6% and 65.2%, respectively, significantly higher than that in 6 cases of normal bile duct respectively (vs 33.3%, 16.7%, 50.0%, 33.3%, 50.0%, 16.7%, respectively, P < 0.05). The positive expression ratio of Smad7 in cases with benign biliary stricture was 70.0%, higher than that in normal bile duct, but this difference is not statistically significant 70.0% vs 50%, P > 0.05). There was a positive correlation between positive expression of TGF-β₁, Smad4 and CTGF in cases with benign biliary stricture.

CONCLUSION: The high expression of TGF-β/Smad/CTGF signaling pathway plays an important role in the pathogenesis of benign biliary stricture.

The intracellular domain of the beta-amyloid precursor protein is stabilized by Fe65 and translocates to the nucleus in a notch-like manner

The beta-amyloid precursor protein (APP) is a ubiquitous receptor-like molecule without a known function. However, the recent recognition that APP and Notch undergo highly similar proteolytic processing has suggested a potential signaling function for APP. After ligand binding, Notch is cleaved by the ADAM-17 metalloprotease followed by an intramembrane cleavage mediated by gamma-secretase. The gamma-secretase cut releases the Notch intracellular domain (NICD), which enters the nucleus and modulates transcription. Because APP is processed similarly by ADAM-17 and gamma-secretase, we reasoned that the APP intracellular domain (AICD) has a role analogous to the NICD. We therefore generated a plasmid encoding the AICD sequence and studied the subcellular localization of the expressed protein (C60). Our results demonstrate that the cytoplasmic domain of APP is a highly labile fragment that is stabilized by forming complexes with Fe65 and can then enter the nucleus in neurons and non-neural cells. These findings strongly support the hypothesis that APP signals in the nucleus in a manner analogous to the function of Notch.

Nested genetic algorithm for resolving overlapping spectra

A nested genetic algorithm, including a genetic parameter level and a genetic implemented level, has been proposed and applied for resolving simulated overlapping spectra. Parameters of genetic algorithms (GA) were optimized by use of the genetic parameter level. The number of overlapping peaks was, moreover, detected simultaneously. Parameters of individual peaks in multiplets were computed by use of the genetic implemented level. It is obvious that the parameters of GA can be optimized and the number of overlapping peaks can be detected by itself. The optimization results are less affected than in traditional curve-fitting by the initial values of the parameters of the overlapping bands. Consequently, the nested genetic algorithm is superior to the curve-fitting technique for resolution of overlapping peaks.

[Spectroscopic study on the high voltage fast pulsed discharge of nitrogen, ammonia or their mixture]

The emission spectra from the pulsed discharge plasma of nitrogen, ammonia or their mixture were measured. In the discharge of pure nitrogen gas, as the pressure increased, the discharge volume decreased and more dissociation of nitrogen molecules occurred due to the higher energy density. In the discharge of ammonia, N,N+ and NH+ were observed, but no NH2 and NH3 were detected, indicating that ammonia, which has the lower dissociation and ionization energies as compared to nitrogen, was highly dissociated. The discharge of the mixture of N2 and NH3 was also studied. The dependence of the dissociation of nitrogen on the ratio of nitrogen to ammonia was investigated by emission spectra. The optimal ratio for nitrogen dissociation was obtained. The advantage of using the mixture of nitrogen and ammonia in the synthesis of nitrides was discussed.

Activation of the human PAX6 gene through the exon 1 enhancer by transcription factors SEF and Sp1

PAX6 is a transcription factor that plays a major role in ocular morphogenesis. PAX6 is expressed in the eye, central nervous system and pancreas. Two alternative promoters, P0 and P1, which are differentially regulated during development, drive PAX6 transcription. We identified a 57 bp cis-regulatory element in exon 1 of the human PAX6 gene exon 1 enhancer (EIE). EIE enhances P1-driven PAX6 expression. Three regions in E1E (E1E-1, E1E-2 and E1E-3) have sequence similarities with binding sites of transcription factors ARP-1, Isl-1 and SEF, respectively. As shown by electrophoretic mobility shift assays, E1E-3, but not E1E-1 or E1E-2, bound to proteins in nuclear extracts of human glioma cells and transcription factor SEF bound to E1E-3. As shown by transient transfection experiments, deletion or site-specific mutations in E1E-3 dramatically decreased P1 promoter activity. Mutations in E1E-2, however, did not affect function of the P1 promoter. Co-transfection of SEF and PAX6 promoter-reporter constructs showed that SEF up-regulates PAX6 gene expression through the P1 promoter. Two Sp1 sites in the E1E region were also shown to be important by transient co-transfection assays. Data from immunoprecipitation and transient transfection assays demonstrated that SEF and Sp1 interacted in vitro and may act together in vivo to regulate PAX6 expression.

A novel Pax-6 binding site in rodent B1 repetitive elements: coevolution between developmental regulation and repeated elements?

Pax-6 encodes a transcription factor that is important in the development of eye and CNS. Identification of Pax-6 target genes is crucial for understanding the gene regulatory network in these developmental processes. Using an in-vitro approach of cyclic amplification of the protein binding sequences (CAPBS), we isolated a PAX6 binding sequence from a human single-copy (sc) DNA library. Characterization of this PAX6 binding sequence revealed a 15bp region (hGCalpha1BLs5) that is sufficient for PAX6 specific binding. From a homology search in the GenBank, we found that an hGCalpha1BLs5-like Pax-6 binding site exists in 21 genes (16 from rodent), 15 of which were shown to be able to bind Pax-6 in vitro. Interestingly, some of these sites occur in B1 repetitive elements. Although hGCalpha1BLs5 is highly similar to a region in B1 repetitive elements, PAX6 does not bind to the consensus sequence in B1. However, a single-step mutation in some B1 elements can lead to a gain of function for PAX6 binding. This experimental evidence and phylogenetic analysis raise an interesting speculation for the coevolution between PAX6 regulation and repeat elements. Since a (Pax-6-binding) null B1 element can be re-activated by even a single-step mutation, it has the potential to recruit gene targets for Pax-6 if it is inserted into the regulatory region, and therefore may play a role for evolutionary modification of Pax-6 regulation.

Use of UvrABC nuclease to quantify benzo[a]pyrene diol epoxide-DNA adduct formation at methylated versus unmethylated CpG sites in the p53 gene

We have used the UvrABC nuclease incision method in combination with ligation-mediated polymerase chain reaction (LMPCR) techniques to map and quantify (+/-)anti-7beta, 8alpha-dihydroxy-9alpha, 10alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]-pyrene (BPDE) adduct formation in the p53 gene of human cells. We found that BPDE adduct formation, as revealed by UvrABC incision, preferentially occurred at methylated CpG sites that correspond to the mutational hotspots observed in human lung cancers. Our hypothesis is that it is this methylated CpG sequence-dependent preferential adduct formation, rather than selective growth advantage, that is the major determinant of the p53 mutation pattern in human cancers. Given the far reaching ramifications of such conclusions for cancer etiology, a legitimate question is raised regarding the reliability of using the UvrABC incision method for quantifying and determining the sequence-dependency of adduct formation. Is the higher frequency of UvrABC cutting at methylated versus unmethylated CpG sites due to the preference of the nuclease for cutting at those sites or due to the preferential formation of BPDE adducts at those sites? In order to distinguish between these two possibilities, we have analyzed the kinetics of UvrABC incision at BPDE adducts formed at either methylated CpG sites versus other sequences, or unmethylated CpG sites versus other sequences in exon 5 of the p53 gene. We have found that the UvrABC cutting kinetics are identical for both cases. On the basis of these results we conclude that under proper cutting conditions, UvrABC nuclease reacts with and incises with equal efficiency, BPDE adducts formed at methylated or unmethylated CpG sites as well as other sequences, and that the extent of UvrABC incision accurately reflects the extent of BPDE-DNA adduct formation. These conclusions were further supported by results obtained using a DNA synthesis blockage assay.

M-wave of the toad electroretinogram

1. In the retina, two distinct, light-evoked releases of K+ have been described. One takes place in the outer plexiform layer (OPL) and is termed the "distal K+ increase." The other takes place in the inner plexiform layer (IPL) and is termed the "proximal K+ increase." Although the distal K+ increase generates the electroretinogram (ERG) b-wave, the contribution of the much larger proximal K+ increase to the ERG is less well understood. In this paper we detail our investigation of the proximal K+ increase and its contribution to the ERG. We describe an ERG component, the M-wave, which had not heretofore been observed in the diffuse-flash, vitreal ERG. 2. We studied the proximal K+ increase and the ERG M-wave in the isolated retina preparation of the toad, Bufo marinus. We used K(+)-sensitive microelectrodes, as well as conventional intra- and extracellular microelectrodes, to record K+ changes, the local (or intraretinal) ERG, the vitreal ERG, and Müller cell responses. 3. As in earlier studies of the amphibian and cat M-wave, we readily observed an M-wave in the intraretinal, or local, ERG (LERG). The M-wave we studied had characteristics similar to those of M-waves that were previously described. Specifically, we found that the M-wave was generated by a Müller cell response to the proximal K+ increase and that both the proximal K+ increase and the LERG M-wave were spatially tuned. 4. We used the aspartate receptor agonist, N-methyl-DL-aspartate (NMA), to reveal that an M-wave is present in the vitreal ERG. Researchers who previously investigated the M-wave were unable to identify an M-wave in the vitreal ERG. We found that the toad ERG M-wave was a small, positive potential that was partially obscured by the much larger b-wave and slow PIII components. 5. We observed that picrotoxin (PTX) had an excitatory effect on inner retina, as evidenced by an enhanced proximal K+ increase and an enhanced M-wave. This result indicates that it is likely that GABAergic inhibition in inner retina plays an important role in retinal processing in the toad. 6. At threshold, we found that the ERG consisted mainly of an M-wave, indicating that the amphibian threshold ERG is driven by proximal retina. This result is analogous to previous observations of the threshold ERG in cat. However, in cat, the M-wave and threshold response have been described as distinct ERG components.(ABSTRACT TRUNCATED AT 400 WORDS)

Transmission through plasma created by laser-induced breakdown of water droplets

The temporally and spatially resolved transmission is measured with a green probe beam through the plasma created by an intense near-IR beam that is incident upon a water droplet. We report the propagation speed of the expanding plasma and the evolution of the transmission decrease and recovery at various locations along a line in the direction of the IR beam.

Behavioral aspects of cigarette smoking among industrial college men of Shanghai, China

A questionnaire survey was conducted among 7,665 students and staff in the factory-operated industrial colleges in Shanghai, China. Response rate was 95.7 per cent. The proportion of smokers among the men was 50.5 per cent; only 0.33 per cent of the women reported they were smokers. Male smokers began smoking upon entering the work force, where social interaction encourages cigarette smoking. Seventy per cent of the male smokers smoked fewer than 10 cigarettes per day. Only 4.3 per cent perceived themselves as very addicted; 3.4 per cent reported they had no confidence in their ability to control the amount they smoke. The Chinese smokers are more likely to succeed in giving up cigarette smoking for at least one day, as well as for longer periods, compared to US smokers. The number of cigarettes smoked may be related to the individual's purchasing power. For China, strategic timeliness in legislative action and education is urgently needed to combat the high prevalence of cigarette smoking in males, at extremely high risk.

Laser-induced breakdown in large transparent water droplets

Recent experiments on the laser-induced breakdown (LIB) of large transparent liquid droplets are reviewed. A physical model of LIB processes is presented with the aim of integrating the following recent results: (1) the internal and near-field distributions for large transparent spheres; (2) the location of LIB initiation based on spatially resolved plasma emission spectroscopic techniques; (3) spatially resolved but time-averaged density of the plasma plumes and temperature of the atomic species within the plasma; (4) the plasma front propagation velocities inside and outside the droplet; and (5) the fate of the remaining superheated droplet and the expelled material.

Time dependence of multiorder stimulated Raman scattering from single droplets

An optical multichannel detection technique was used to measure simultaneously the time profiles of the input laser pulse and the elastic scattering, as well as the time profiles of the spectrally resolved multiorder stimulated Raman scattering (SRS), from single droplets. The time delay between the multiorder SRS and the input laser pulse is consistent with the generalized four-wave mixing process for first-order stimulated Raman growth, starting from spontaneous noise or the parametric signal. The presence of an internal plasma associated with laser-induced breakdown within a droplet quenches the SRS and increases the elastic scattering.

Propagation velocity of laser-induced plasma inside and outside a transparent droplet

The supersonic propagation velocity of the emission front of plasma produced by laser-induced breakdown of a micrometer-sized transparent droplet flowing in a gas was measured with a streak camera at three intensity levels. At low input intensity, the plasma velocities in the gas away from and toward the shadow face were determined. At medium input intensity, the plasma velocities in the gas outside the shadow face and within the liquid (traveling toward the illuminated face) were measured. At high input intensity, the plasma velocities in the gas outside the shadow face, within the liquid, and in the gas outside the illuminated face were deduced.

Experimental comparison of broadband rotational coherent anti-Stokes Raman scattering (CARS) and broadband vibrational CARS in a flame

Broadband rotational coherent and anti-Stokes Raman scattering (CARS) and vibrational CARS measurements have been performed to determine the N(2) temperature in a flame (1800-2000 K). Comparisons between these two CARS approaches indicate that, despite loss of signal strength with increasing temperature, rotational CARS is a potentially viable technique for flame-temperature measurements.

Spatially and spectrally resolved multipoint coherent anti-Stokes Raman scattering from N(2) and O(2) flows

Single-shot spectrally resolved broadband rotational coherent anti-Stokes Raman scattering (CARS) from multiple points along a line intersecting a flow has been observed for N(2) and O(2). A large-angle phase-matching configuration was used to achieve spatial resolution of 0.1 mm x 0.1 mm x 0.1 mm for each of 20 points in the interactionvolume. Single-shot multipoint CARS of N(2) at different temperatures and of several species in a coflowing jet was observed.

Simultaneous observation of rotational coherent Stokes Raman scattering and coherent anti-Stokes Raman scattering in air and nitrogen

We report the first simultaneous observation to our knowledge of pure rotational coherent Stokes Raman scattering (CSRS) and coherent anti-Stokes Raman scattering (CARS) using broadband generation and detection. Three-dimensional small-angle phase-matching conditions for CSRS and CARS processes are discussed.