Analysis of HBs antigen negative variant of hepatitis B virus: unique substitutions, Glu129 to Asp and Gly145 to Ala in the surface antigen gene.

We analyzed the surface gene (S gene) of a hepatitis B virus (HBV) isolate with mutations of envelope protein that rendered it undetectable by both a monoclonal hepatitis B surface antigen (HBsAg) enzyme-linked immunosorbent assay (ELISA) and polyclonal HBsAg radioimmunoassay (RIA). Sequencing of independently cloned products of HBV polymerase chain reaction revealed several point mutations within the S gene. Rare substitution was identified both at positions 129 (glutamine to asparagine) and at position 145 (glycine to alanine) in the 'a' determinant region, which is considered to be within a larger antigenic area known as the major hydrophilic region (MHR). A computer-assisted analysis of protein secondary structure could not find any significant difference between this mutant and wild-type HBsAg. However, the substitution of substitution glycine to alanine at position 129 introduce a putative glycosylation site (Asn-Gly-Thr), which may interfere with the antigenicity of HbsAg. Also, HBV variant with substitution at position 145 (Gly to Ala) has been recently reported to be antigenically altered and to show impaired recognition by polyclonal hepatitis B hyperimmune globulin in vitro. These genetic mutations in the S gene inside MHR may allow to escape detection by standard HBsAg assays.

Early stage gastric lymphoma: is operation essential?

To assess the efficacy of primary chemotherapy for treatment of early stage patients with gastric lymphoma, multiple agent chemotherapy was given to patients prior to surgery. Five patients with stages IE and IIE of primary gastric lymphoma (54-65 years of age; three men, two women) were treated with multiple agent chemotherapy prior to gastric resection. In all patients the diagnosis was established by endoscopic biopsy. Two patients had stage IE disease, and three had stage IIE. Histopathologically, there was one diffuse large cell lesion and four diffuse medium cell lesions. All patients received two cycles of VEPA every 4 weeks. On the 16th to 44th day after completion of chemotherapy, total gastrectomy, systematic dissection of regional lymph nodes with resection of the caudal pancreas, and splenectomy were performed. Swelling of the regional lymph nodes was noted in four cases. In all five cases, histologic findings revealed no residual cells of malignant lymphoma in the resected specimen. None of the patients had no evidence of recurrence at 12 to 40 months after surgery. Primary chemotherapy alone thus resulted in the disappearance of malignant cells in stage IE/IIE gastric lymphoma. Our results suggest that surgery may not be an essential procedure for treatment of early stage gastric lymphoma.

[A case report of scimitar syndrome: a new technique in the correction of partial anomalous pulmonary venous drainage].

A twenty eight year-old man with anomalous pulmonary venous drainage from the right lung to the inferior vena cava (scimitar syndrome) underwent surgical treatment. We have successfully modified the surgical technique that consists of using the anterior wall of the right atrium, to form a tunnel that will divert the anomalous pulmonary vein to the left atrium. After rerouting of the anomalous pulmonary vein, the anterior wall of the right atrium was reconstructed with a polytetrafluoroethylene patch. To our knowledge, this is the first time this technique has been used to correct this syndrome.

[A case report of pulmonary arterio-venous fistula complicated with hereditary hemorrhagic telangiectasis].

A 5-year-old girl with multiple pulmonary arterio-venous fistulae was reported. Both her mother and grandmother have been diagnosed as the same disease previously. Her grandmother was treated with resection of the right basal segment for arterio-venous fistulae. Her mother is well with fistulae for more than 20 years. The patient was operated upon to enucleate two larger fistulae in segments 3 and 6 of right lung. Her postoperative course was uneventful. She was discharged from the hospital on the 22nd postoperative day. Pulmonary arteriovenous fistulae are thought to be a part of the hereditary hemorrhagic telangiectasis. Enucleation of the larger fistulae of the lung are preferable even for multiple lesions.

[A clinical study on 34 cases of urothelial cancer of upper urinary tract].

Thirty-four cases of tumor of the renal pelvis or ureter or both have been treated in our department during the past decade. The primary tumor was in the renal pelvis in 11 cases, in the ureter in 21 cases and in the ureter and renal pelvis in 2 cases, a co-existent tumor in the bladder was found in 4 cases. Seventeen patients had a tumor on the right side and 17 on the left side. The most frequent symptom was gross hematuria (70.6%) and flank pain was the presenting symptom in 7 cases (20.6%). On the intravenous pyelography, a filling defect in the renal pelvis or ureter (41.2%) and nonvisualization (53.0%) were frequent findings. Twenty-nine cases had undergone total nephroureterectomy with resection of a bladder cuff, 3 had simple nephrectomy and 2 had open biopsy alone. Postoperative radiation therapy was done in 1 case, chemotherapy in 10 cases, and 6 cases of them were treated by CAP therapy (cis-dichlorodiamine platinum, doxorubicin and cyclophosphamide). Actual and relative 5-year survival rates were 53.8% and 63.5%, and no significant difference was found in survival rate between the patients with renal pelvic tumors and those with ureteral tumors.

Modified spinel, Beta-manganous orthogermanate: stability and crystal structure.

A new high-pressure polymorph with a modified spinel structure, beta-Mn(2)GeO(4), is stable in a pressure range intermediate between the field of the polymorph with the olivine structure and that of another high-pressure polymorph. Oxygen atoms are located approximately in cubic close packing with manganese and germanium atoms in octahedral and tetrahedral interstices, respectively, as in the spinel structure; however, germanium atoms form Ge(2)O(7) groups instead of isolated GeO(4) groups.