An improved computer method to prepare 3D magnetic resonance images of thoracic structures

The mediastinal and cardiovascular anatomy is complex. We have developed a three-dimensional (3D) reconstruction system for the major mediastinal structures using magnetic resonance imaging data on a NeXT workstation. The program uses a combination of automatic and manual procedures to determine the contours of the cardiac structures. The geometric centers of the contours are connected by a 3D space curve, and the central axis of each cardiac structures is determined. The contours are projected on the perpendicular plane to the central axis and semiautomatically processed until the contours of one pixel are obtained. Then the surface rendering with transparency is performed. Compositing combines two images so that both appear in the composite, superimposed on each other. Demonstration of the various mediastinal lines and cardiovascular diseases by the composits of the partly transparent 3D images has promoted a better understanding of the complex mediastinal and cardiovascular anatomy and diseases.     

Tumor Recurrence following Resection for Early Gastric Carcinoma and Its Implications for a Policy of Limited Resection

p < 0.02) more recurrent than mucosal ones (0.29%). Of the 16 patients with recurrence, 10 (62.5%) died within 5 years after surgery, frequently because of blood-borne metastasis. Macroscopically elevated components, the degree of histologic differentiation, and lymph node metastasis significantly contributed to the postoperative recurrence. After detailed analysis of submucosal carcinomas, it is strongly suspected that carcinomas with a macroscopically elevated component were significantly associated with nodal involvement and microvessel invasion, and that these abnormalities lead to recurrence. Among the early gastric carcinomas, differentiated submucosal carcinomas with a macroscopically elevated component, lymph node metastasis, or both have the most potential of recurrence after surgery. Mucosal carcinomas must be restricted to limited surgery, but, blood-borne metastasis should be carefully avoided.     

Expression of genes involved in repair of DNA double-strand breaks in normal and tumor tissues

BACKGROUND: DNA double-strand breaks (DSB) are the major lethal lesions induced by ionizing radiation. The capability for DNA DSB repair is crucial for inherent radiosensitivity of tumor and normal cells. DNA-PKcs, Ku 70, Ku 85, Xrcc4, and Nbs1 play a critical role in DNA DSB repair. METHODS: We immunohistochemically investigated the expression of DNA-PKcs, Ku 70, Ku85, Xrcc4, and Nbs1 in 134 specimens from various normal and tumor tissues with different radiosensitivity. RESULTS AND CONCLUSION: Immunopositivity to Ku70, Ku85, DNA-PKcs, Xrcc4, and Nbs1 was found in all tumor tissues examined. The staining for Ku70, Ku85, and DNA-PKcs was nuclear; but, for Xrcc4 and Nbs1, it was nuclear and cytoplasmic. There were no apparent differences in the expression of these five proteins among cancerous tissues and the corresponding normal tissues. No apparent differences in nuclear staining intensity were detected in the expression of these five proteins among tumor tissues with different radiosensitivity, although non-Hodgkins' lymphoma (B or T cell) tended to show a lower expression than the others. The stromal cells generally expressed these five proteins at much lower frequency than either tumor or epithelial cells in both tumor and normal tissues.     

A neutralizing epitope of human immunodeficiency virus type 1 has homologous amino acid sequences with the active site of inter-{alpha}-trypsin inhibitor

A neutralizing epitope (epitope beta) of the HTLV-IIIB strain of HIV-1 was mapped to 24 amino acids of an external envelope glycoprotein (gp120) using a neutralizing monoclonal antibody (0.5 beta) and hetero-antisera against synthetic peptides encoding gp120. Proteins that have homologous sequences with epitope beta were sought from a databank of protein sequences to assess biological features of epitope beta. The results showed that epitope beta was found to have homologous sequences to inter-alpha-trypsin inhibitor (ITI). The homologous region of ITI included the active site of the protein. Synthesized peptides including epitope beta were good substrates for trypsin, because these peptides inhibited trypsin activities in a competitive manner (Ki = 24.5 microM). Human urinary trypsin inhibitor (UTI), a protein indistinguishable from ITI, as well as synthetic peptides including epitope beta inhibited syncytium formation caused by the LAV-1-infected CCRF-CEM and uninfected Molt-4 cells in a dose-dependent manner (0.1-1 mM). These findings suggest that epitope beta of HIV-1 could be substrate of protease upon HIV-1 infection and also suggest that protease inhibitory activity of epitope beta may play a role in the pathophysiology of HIV-1-infected individuals.     

Histo- and immunopathological features of terminal AIDS. An autopsy case of a Japanese man with neurological signs as initial symptoms

An autopsy case of a 37-year-old Japanese man, confirmed as an AIDS patient infected by an undetermined route of transmission, is presented. The initial symptoms of full-blown AIDS in this case were neurological, and the patient died of severe pneumonia 9 months after onset. The main histo- and immunopathological features were a marked depletion of helper-inducer T cells and dendritic reticulum cells in the lymphoid tissues, opportunistic infections, and some neuropathologic changes. Very few cells, possibly macrophages, immunoreactive with a monoclonal antibody (VAK-5) against HIV-gag protein P24 were found in the mediastinal lymph nodes. Numerous pathogens had induced opportunistic infections in many organs: severe and generalized cytomegalovirus infection, Pneumocystis carinii pneumonia, bronchopneumonia (possibly due to Pseudomonas aeruginosa), candidiasis in the tongue and oral cavity, and atypical mycobacteriosis in the pulmonic hilar lymph nodes. Vascular proliferation was found in the perinodal regions of some lymph nodes, but this was not neoplastic vascular proliferation compatible with that of localized Kaposi's sarcoma.     

Surgical procedures in gallbladder cancer with special reference to its macroscopic appearance

To investigate the relationships of the gross appearance to cancer depth and microinvasion in gallbladder cancer, thirty-three cancers were macroscopically subgrouped: papillary (n=8), nodular (n=6), papillo-invasive (n=1), nodulo-invasive (n=11), and invasive (n=7) type, respectively. Papillary type cancers were limited to the mucosa or the muscularis propria, without microinvasion. Most nodular type cancers infiltrated to the subserosa with moderate microinvasion. The other types of cancer frequently invaded the subserosa or more, with high incidence of microinvasion. Only the papillary type cancers indicated simple cholecystectomy, the other types should be operated in accordance with infiltration depth and degree of involvement.