Mast cell chymase expression in Helicobacter pylori-associated gastritis.

AIMS: To study the role of mast cell chymase in the inflammatory processes of human chronic gastritis. Experimental studies have shown that mast cell chymase stimulates inflammatory cell accumulation, and contributes to angiotensin II formation. METHODS AND RESULTS: Tissue sections from human stomachs with Helicobacter pylori-associated gastritis (surgery/autopsy n = 20; biopsy n = 16) and normal stomachs (n = 10) were studied using immunohistochemical single and double labelling techniques. Monoclonal antibodies used were directed against mast cell chymase, tryptase, neutrophils (CD66b, elastase, and myeloperoxidase), macrophages, T-lymphocytes, and interleukin (IL)-4. The expression of angiotensin-converting enzyme and angiotensin II type 1 receptor was investigated using immunohistochemical analysis and the reverse transcription-polymerase chain reaction. The number of chymase-positive mast cells was significantly higher (P < 0.0001) in H. pylori-associated gastritis than in normal stomachs. Increased expression of chymase in inflamed mucosa was closely related to an increase in the accumulation of neutrophils, macrophages, T-lymphocytes, and IL-4-positive cells. The expression of angiotensin-converting enzyme and angiotensin II type 1 receptor was not altered in gastritis specimens. CONCLUSIONS: These observations suggest that mast cell chymase may be an important mediator in the inflammatory processes of human H. pylori-associated gastritis.

Mast cell chymase expression and mast cell phenotypes in human rejected kidneys.

BACKGROUND: Mast cells (MCs) are known to participate in various types of chronic disease, but their role in chronic renal rejection is poorly understood. Recently, distinct phenotypes of MCs have been described in humans by the demonstration of one protease, chymase. Hence, we questioned whether chymase in MCs could play a role in the pathogenesis of renal rejection in humans. METHODS: We investigated MC chymase expression and MC phenotypes, using immunohistochemical single- and double-staining techniques, in nephrectomy (N = 13) and biopsy (N = 8) specimens of human rejected kidneys. Tissue chymase levels were determined by enzymatic assay for chymase activity. We also examined the association between MC chymase expression and the degree of interstitial fibrosis in these renal allografts. RESULTS: Based on chymase positivity, rejected kidneys were divided into two groups, a chymase-negative [Chy(-)] group and a chymase-positive [Chy(+)] group. Quantitative analysis showed that the number of chymase-positive MCs and tissue chymase levels were significantly higher in the Chy(+) group than in the Chy(-) group. Furthermore, the interstitial fibrotic area in the Chy(+) group was significantly larger than that in the Chy(-) group. Immunodouble staining analysis also demonstrated that a new MC phenotype, positive for chymase but negative for tryptase, was present in the human rejected kidney. CONCLUSIONS: These results show that increased expression of chymase in MCs is related to the severity of interstitial fibrosis in human rejected kidneys.

Cytomegalovirus associated pancreatitis in a patient with systemic lupus erythematosus.

Pancreatitis can develop as a complication of systemic lupus erythematosus (SLE). Steroids are considered one of the possible causes of this complication, but the pathological mechanism is unclear. We describe an autopsy case of a 29-year-old woman with cytomegalovirus (CMV) associated pancreatitis that developed during steroid therapy for her SLE. Many parenchymal cells with cytomegalic inclusions were seen in the patient's pancreas, especially in lesions showing active inflammation, and transcripts of CMV major immediate-early and late genes, markers of active viral replication, were detected. These findings suggest that CMV played an etiological role in the pancreatic disorder.

Outbreak of human parvovirus B19 in hospital workers.

We report an outbreak of human parvovirus B19 (HPV B19) infection affecting five nursing staff, four hospital office workers and one physiotherapist and its possible transmission between hospital staff. We investigated the presence of the virus in serum specimens using a nested PCR assay to confirm HPV B19 infection. The viral genome was detected in serum specimens from a nurse with a rash and arthralgia and from three hospital office workers with a febrile illness. The DNA sequence of the PCR products from three staff members was identical. Our findings suggest that transmission of HPV B19 between hospital staff members occurred.

Quantitative analysis and in situ localization of human telomerase RNA in chronic liver disease and hepatocellular carcinoma.

Telomerase is a specialized type of reverse transcriptase that catalyzes the synthesis and extension of telomeric DNA. High levels of telomerase activity have been detected in most hepatocellular carcinoma (HCC) tissues; very weak telomerase activity is, however, detected in approximately half of nontumorous chronic liver disease tissues. The purpose of this study was to investigate the possible source of this weak telomerase activity in these tissues using quantitative competitive reverse transcription (RT)-polymerase chain reaction (PCR) and in situ RT-PCR. Competitive RT-PCR indicated that the relative amount of human telomerase RNA (hTR) was significantly higher in chronic hepatitis or liver cirrhosis compared with the normal liver (p < 0.005), and in HCC compared with the normal liver (p < 0.001) and with chronic hepatitis or liver cirrhosis (p < 0.0001). In the normal liver tissue, hTR was detected by in situ RT-PCR in occasional sinusoidal cells and nuclei of occasional hepatocytes. In tumor-free liver or tumor-bearing liver, hTR was detected in sinusoidal cells, infiltrating lymphocytes, occasional proliferative bile ductal epithelial cells, and the nuclei of occasional hepatocytes. In HCC, hTR was detected in nuclei of all HCC cells as an intense signal and in sinusoidal cells. These results indicate that the amount of hTR increases in the nuclei of hepatocytes during hepatocarcinogenesis, and that the cells associated with the weak telomerase activity in approximately half of the nontumorous chronic liver lesions are mainly migrating lymphocytes and sinusoidal cells.

Characteristics of patients with hepatitis C virus with and without GB virus C/hepatitis G virus co-infection and efficacy of interferon alfa.

GB virus C/hepatitis G virus (GBV-C/HGV) infection seems to be common among patients with hepatitis C virus (HCV) infection. We studied retrospectively the proportions of patients with GBV-C/HGV RNA and antibodies to the GBV-C/HGV second envelope protein (anti-E2) among 149 subjects with chronic hepatitis C who had received interferon alfa. The clinical characteristics of patients with GBV-C/HGV RNA or anti-E2 were examined, as was the efficacy of the treatment. Stored serum specimens were tested for GBV-C/HGV RNA by the reverse transcription polymerase chain reaction and for anti-E2 by an enzyme-linked immunosorbent assay. Of the 149 patients before therapy, 8 (5%) had GBV-C/HGV RNA only, 72 (48%) had anti-E2 only, and 4 (3%) had both. The mean age of patients with GBV-C/HGV RNA (some with anti-E2) was significantly less than that of patients with anti-E2 only. Results of laboratory and histological evaluations were not different depending on the presence of GBV-C/HGV RNA or anti-E2. The GBV-C/HGV RNA titer decreased during therapy in all 12 patients with GBV-C/HGV RNA; only 4, with a low titer before therapy and with anti-E2 detected at some time, had sustained clearance of GBV-C/HGV. Our results suggested that half of the patients with chronic hepatitis C had been exposed to GBV-C/HGV, but in almost all, the virus had been cleared; also, even chronic GBV-C/HGV infection did not affect the severity of the disease arising from HCV. Interferon alfa treatment was sometimes effective against GBV-C/HGV, and anti-E2 may be associated with clearance of GBV-C/HGV.

Expression of platelet-derived growth factor and its receptor in livers of patients with chronic liver disease.

To find if platelet-derived growth factor contributes to liver fibrosis in chronic liver disease, we studied the expression of the B-chain of this cytokine and its beta-receptor in livers of patients with chronic hepatitis or cirrhosis. Seventeen patients were included in this study. Five specimens of liver tissue obtained during autopsy from subjects without liver disease were used as controls. The location of the peptides was identified by an immunohistochemical technique with monoclonal antibodies. Expression of mRNA for the B-chain was assessed by in situ hybridization. Cells stained for the B-chain and expressing its mRNA were identified as macrophages. In control tissues, only a few cells were stained. In the patients' specimens, most stained cells were in portal areas and their number increased with histologic liver damage. In intralobular areas, the stained cells were seen in regions of focal necrosis. Portal mesenchymal and perisinusoidal cells expressed beta-receptor. These cells were dense in periportal areas, where many myofibroblast-like cells were seen. These findings suggest that the B-chain of platelet-derived growth factor is released mainly by macrophages involved in inflammatory reactions. This cytokine probably acts on myofibroblast-like mesenchymal cells, and may be implicated in liver fibrosis in chronic liver disease.

[A case report of left limb compartment syndrome associated with laparoscopic surgery].

A 63-year-old male patient with early gastric cancer was attempted for laparoscopic wedge resection of the stomach. After the introduction of anesthesia, bandage of bilateral leg was carried out to prevent deep venous thrombosis during laparoscopic surgery. Although the procedure was converted to open surgery, the bandage has been continued throughout the surgery for 6 hours. After the operation, the swelling and severe tenderness at his left leg was observed. MRI revealed remarkable edema in left deep posterior compartment. Under diagnosis of left limb compartment syndrome, fasciotomy was carried out. Postoperatively the patient did well without any functional disturbance.