In vitro early changes in intercellular junctions by treatment with a chemical carcinogen

To examine early intercellular junction changes caused by treatmentwith 9, 10-dimethyl-l, 2-benzanthracene (DMBA), rat lingualepithelium was cultivated in isolation and observed by electrophysiological,freeze-fracture and whole-mount electron microscopy. Electrophysiologicalmeasurements showed a transient decrease in membrane potentialof -10.2 mV 6 h after the treatment. It returned to almost thesame level as that of the control group 1 day later. Six hoursafter treatment, input resistance decreased rapidly to 5.3 Mbut increased to 18.0 M 12 h after treatment. Transient reductionof input resistance and membrane potential occurred prior tothe decrease in the coupling ratio 6 h after treatment withDMBA. In freeze-fracture replicas, the number of gap junctionsdecreased by 45% of the control value 6 h after treatment withDMBA. At 12 h and thereafter, the number and area of gap junctionssubsequently decreased by 60–80% of the control value.Alterations in the number and area of desmosomes were similarto those of the gap junctions. The formation of epithelial cytoskeletons,partially devoid of the 2–4 and 5–8 nm filamentswas also observed. A decrease in the density of filament networksbeneath the plasma membranes was especially apparent. Treatmentwith a carcinogen brought about morphological cellular changesas early as 6 h after treatment, and such early changes mighttrigger metabolic cellular abnormalities. Affected cells appearto move away from normal cells in a process of repeated destructionand revision of intercellular junctions, and cytoskeletons.     

Direct visualization of glucagon‐like peptide‐1 secretion by fluorescent fusion proteins

Live‐cell imaging with fluorescent proteins (FPs) is a powerful tool for investigating the exocytosis processes of hormones. However, the secretion process of glucagon‐like peptide‐1 (GLP‐1) has not been visualized by FPs, which might be because tagging FPs inhibits GLP‐1 synthesis through the post‐translational processing from proglucagon. Here, we have developed FP‐tagged GLP‐1 by inserting FPs into the middle of GLP‐1 and adding the proglucagon signal peptide. Confocal imaging confirmed that GLP‐1 fused to FPs with high folding efficiency showed granular structure, in which secretory vesicle markers colocalized. The fluorescence intensity of FP in the culture supernatant from cells treated with KCl or forskolin was significantly increased compared with those from untreated cells. Furthermore, FP‐tagged GLP‐1 enables direct visualization of stimulation‐dependent exocytosis of GLP‐1 at a single granule resolution with total internal reflection fluorescence microscopy. FP‐tagged GLP‐1 might facilitate the screening of GLP‐1 secretagogues and the discovery of new antidiabetic drugs.     

Factors Associated with Pneumocystis jirovecii Pneumonia in Patients with Rheumatoid Arthritis Receiving Methotrexate: A Single-center Retrospective Study

Objective To investigate the risk factors for the development of Pneumocystis jirovecii pneumonia (PCP) in patients with rheumatoid arthritis (RA) undergoing methotrexate (MTX) therapy. Methods This single-center retrospective cohort study included consecutive patients with RA who received MTX for at least one year. The study population was divided into PCP and non-PCP groups, depending on the development of PCP, and their characteristics were compared. We excluded patients who received biologic disease-modifying anti-rheumatic drugs (DMARDs), Janus kinase inhibitors, and anti-PCP drugs for prophylaxis. Results Thirteen patients developed PCP, and 333 did not develop PCP. At the initiation of MTX therapy, the PCP group had lower serum albumin levels, a higher frequency of pulmonary disease and administration of DMARDs, and received a higher dosage of prednisolone (PSL) than the non-PCP group. A multivariate Cox regression analysis revealed that the concomitant use of PSL [hazard ratio (HR) 5.50, p=0.003], other DMARDs (HR 5.98, p=0.002), and serum albumin <3.5 mg/dL (HR 4.30, p=0.01) were risk factors for the development of PCP during MTX therapy. Patients with these risk factors had a significantly higher cumulative probability of developing PCP than patients who lacked these risk factors. Conclusion Clinicians should pay close attention to patients with RA who possess risk factors for the development of PCP during MTX therapy.     

A Rare Case of Rheumatoid Arthritis with Tocilizumab-induced Intestinal Mucosal Injury

Intestinal mucosal injury that develops as a complication of tocilizumab (TCZ) is usually associated with diverticulosis. We herein report a rare case of TCZ-induced intestinal mucosal injury in the absence of diverticulosis. A 74-year-old woman suffering from rheumatoid arthritis started taking TCZ. Six months later, she complained of hematochezia and abdominal pain. Colonoscopy revealed multiple ulcers spreading from the cecum to the transverse colon but no diverticulosis. These lesions were cured at three months after the discontinuation of TCZ. We should consider TCZ as a risk factor for intestinal mucosal injury, even if patients have no history of intestinal disease associated with diverticulosis.     

Skip mediastinal nodal metastases in non-small cell lung cancer

Objective: To reveal the incidence and clinical significance of mediastinal nodal metastases without N1-station nodal metastases (‘skip-N2 metastases’) in non-small cell lung cancer (NSCLC). Methods: A total of 450 NSCLC patients who underwent tumor resection with a systemic mediastinal nodal dissection were retrospectively reviewed. p53 status and proliferative activity represented as proliferative index (PI) were also examined immunohistochemically. Results: Skip-N2 metastases were documented in 49 (13%) patients of all 450 patients; among 334 patients without N1-nodal involvement, 18% patients had skip-N2 metastases. The postoperative survival of skip-N2 patients was almost same as that for patients with metastases to both N1 and N2 nodes. Skip-N2 metastases were significantly more frequent in male patients and squamous cell carcinoma patients. In addition, the mean PI for tumor with skip-N2 metastases was significantly higher than that for any other pathologic nodal (pN)-status diseases. Combined with histologic type and PI, the incidences of skip-N2 metastases for adenocarcinoma showing lower PI were only 5% (7/137) of all patients and 7% (7/94) of patients without N1-nodal involvement. Conclusions: N1 nodal status is not a useful predictor of N2 nodal status in NSCLC, because skip-N2 metastases were documented in 18% patients showing no N1-nodal involvement. However, N1 node-guided dissection might be performed in patients with adenocarcinoma showing lower PI, because the incidence of skip-N2 metastases was extremely low.     

Glycolysis inhibitors as a potential therapeutic option to treat aggressive neuroblastoma expressing GLUT1

Background/PurposeIncreased glycolysis is among the biochemical characteristics of cancerous tissue. The glucose transporter isoform 1 (GLUT1) gene encodes a key factor for glucose transport into cancerous tissue. However, the expression and functional significance of GLUT1 in neuroblastoma have not been fully characterized. Therefore, we investigated the association of GLUT1 expression with clinical outcomes in patients with neuroblastoma using immunohistochemical staining for GLUT1 in neuroblastoma tissues. We also assessed the efficacy of glycolysis inhibition as an anticancer treatment in neuroblastoma cell lines with altered expression of GLUT1.MethodsWe obtained total RNA from cancerous tissue by microdissection in 47 patients with neuroblastoma. GLUT1 expression levels were evaluated by quantitative real-time polymerase chain reaction. We analyzed the association of GLUT1 expression levels with clinical outcomes. We also examined changes in GLUT1 expression and proliferative responses in vitro using 4 neuroblastoma cell lines treated with a glycolysis inhibitor, 3-Bromopyruvate acid.ResultsElevated GLUT1 expression was associated with poor prognosis. Moreover, elevated GLUT1 expression independently predicted overall survival. Immunohistochemical analysis showed that GLUT1 expression tended to be localized to the centers of neuroblastoma cell nests. Our in vitro studies showed that 3-Bromopyruvate acid significantly suppressed the proliferation of neuroblastoma cells with high GLUT1 gene expression compared with those with low expression.ConclusionGlycolysis inhibitors are a potential therapeutic option for treating aggressive tumors expressing GLUT1.     

The accuracy of transcutaneous carbon dioxide monitoring during laparoscopic surgery

BACKGROUND: Laparoscopic procedures are considered relatively low-invasive. However, there exists a small but important risk of developing complications related to carbon dioxide (CO2) insufflation. End-tidal CO2 (PetCO2) monitoring may not be a sufficient guide to adjust pulmonary ventilation during laparoscopic surgery, and arterial CO2 (PaCO2) monitoring is not always indicated. We evaluated the accuracy and feasibility of transcutaneous CO2 (PtcCO2) monitoring during laparoscopic surgery. METHODS: Thirty adult patients undergoing abdominal or gynecological laparoscopic surgery were studied. PtcCO2, PaCO2 and PetCO2 were measured before laparoscopy, and 30 and 60 minutes after beginning of CO2 insufflation. PtcCO2 and PaCO2 were also measured in the recovery room under spontaneous respiration. RESULTS: During operation, the PtcCO2 values demonstrated a high degree of correlation with PaCO2 (r = 0.92), and PetCO2 values also demonstrated generally a good correlation with PaCO2 (r = 0.85). The PtcCO2 PaCO2 gradient was -0.6 +/- 2.2 mmHg, while the PetCO2-PaCO2 gradient was -3.9 +/- 2.7 mmHg. In the recovery room, PtcCO2 values still demonstrated a high correlation with PaCO2 (r = 0.91). CONCLUSIONS: The transcutaneous devices provide an effective method for non-invasive monitoring of PCO2 in situations where continuous monitoring of CO2 levels is desired such as peri-operative period of laparoscopic surgery.     

Primary mucosa-associated lymphoid tissue-type lymphoma arising in the kidney

Abstract:   We report a case of primary low-grade lymphoma of mucosa-associated lymphoid tissue (MALT) arising from the kidney in a 30-year-old man with an abdominal mass in the right flank detected by ultrasonography. Radical nephrectomy was performed under a preliminary diagnosis of renal cell carcinoma. The final histological diagnosis was MALT-type lymphoma. To the best of our knowledge, only five reports of primary MALT-type lymphoma in the kidney have been published in the literature so far. All cases were surgically treated and only one case went on to chemotherapy postoperatively.     

Perimembrane Aurora-A Expression is a Significant Prognostic Factor in Correlation with Proliferative Activity in Non-Small-Cell Lung Cancer (NSCLC)

Purpose Aurora-A, also known as STK15/BTAK, is a member of the protein serine/threonine kinase family, and experimental studies have revealed that Aurora-A plays critical roles in cell mitosis and in carcinogenesis. However, no clinical studies on Aurora-A expression in non-small-cell lung cancer (NSCLC) have been reported. Thus, the present study was conducted to assess the clinical significance of Aurora-A status. Experimental Design A total of 189 consecutive patients with resected pathologic (p-)stage I-IIIA, NSCLC were retrospectively reviewed, and immunohistochemical staining was used to detect Aurora-A expression. Results Aurora-A expression was negative in 31 patients (16.4%); among Aurora-A positive patients, 124 patients showed pure diffuse cytoplasmic Aurora-A expression and the other 34 patients showed perimembrane Aurora-A expression. Perimembrane Aurora-A tumors showed the highest proliferative index (PI) (mean PIs for negative, diffuse cytoplasmic, and perimembrane tumors: 49.2, 41.7, and 63.5, respectively; P < .001). Five-year survival rates of Aurora-A negative, diffuse cytoplasmic, and perimembrane patients were 67.8%, 66.7%, and 47.6%, respectively, showing the poorest postoperative survival in perimembrane patients (P = .033). Subset analyses revealed that perimembrane Aurora-A expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. A multivariate analysis confirmed that perimembrane Aurora-A expression was an independent and significant factor to predict a poor prognosis. Conclusions Perimembrane Aurora-A status was a significant factor to predict a poor prognosis in correlation with enhanced proliferative activity in NSCLC.     

Laparoscopic choledochotomy in management of choledocholithiasis

PURPOSE: Laparoscopic choledochotomy on patients indicated for common bile duct exploration was carried out according to an algorithm for managing choledocholithiasis. This study describes retrospectively our method and evaluates a new cystic duct biliary decompression cannula (J-tube) as an alternative to the T-tube. METHODS: Patients with confirmed choledocholithiasis (n=46) underwent laparoscopic choledochotomy. The T-tube was inserted in cases with suspected retained stones after common bile duct clearance, and the J-tube (950-mm long, 4 Fr) with a tapered and J-shaped segment at the distal end was inserted in other cases. RESULTS: Only 1 case was converted to open surgery (success rate, 97.8%); the J-tube was inserted in 30 patients and the T-tube in 15. The median operation time, hospital stay, and the interval until removal of the tube were significantly shorter with J-tube than with T-tube cases. Bile leakage after surgery occurred in 4 J-tube and 2 T-tube cases with one residual stone in each case. CONCLUSIONS: The transcystic decompression tube is easily and safely inserted with the J-kit. Among several strategies currently available for the management of choledocholithiasis, laparoscopic choledochotomy with the use of the J-tube is one of the safest and most feasible methods.