A Cost-Effective Immobilization Method for MBP Fusion Proteins on Microtiter Plates Using a Gelatinized Starch-Agarose Mixture and Its Application for Convenient Protein-Protein Interaction Analysis.

The detection and quantification of protein-protein interactions (PPIs) is a crucial technique that often involves the use of recombinant proteins with fusion protein tags, such as maltose-binding protein (MBP) and glutathione-S-transferase (GST). In this study, we improved the cohesive and sticky properties of gelatinized starch by supplementing it with agarose, resulting in a harder gel that could coat the bottom of a microtiter plate. The resulting gelatinized starch/agarose mixture allowed for the efficient immobilization of MBP-tagged proteins on the coated plates, enabling the use of indirect ELISA-like PPI assays. By using the enzymatic activity of GST as an indicator, we succeeded in determining the dissociation constants between MBP-tagged and GST-tagged proteins on 96-well microtiter plates and a microplate reader without any expensive specialized equipment.

Pathologic reappraisal of wallenberg syndrome: a pathologic distribution study and analysis of literature.

BACKGROUND: Wallenberg syndrome was first reported by Adolf Wallenberg as arising due to the obstruction of the posterior inferior cerebellar artery (PICA), which caused an infarct in the lateral medulla oblongata (MO). METHOD: This study was carried out on brain tissue from 2 patients with typical Wallenberg syndrome and 10 autopsy cases without central nervous system disturbances. RESULTS: Patient 1 exhibited the 3 major neurological symptoms of right crossed sensory disturbance, right cerebellar ataxia and bulbar palsy. There was the pathological obstruction of the right vertebral artery (VA). Regarding the histopathlogical distribution, the infarct extended on the right side to the lateral spinothalamic tract, nucleus of the spinal tract of the trigeminal nerve, spinal tract of the trigeminal nerve, inferior cerebellar peduncle, spinocerebellar tract and nucleus ambiguous. Moreover, a clear infarct in the left lateral MO was pathologically identified, but pathological obstruction of the left PICA or left VA could not be found. The left cerebellar ataxia and bulbar palsy were observed among these 3 major symptoms. Patient 2 showed the 3 major symptoms of right crossed sensory disturbance, right cerebellar ataxia and bulbar palsy. A pathological luminal occlusion was identified in the right PICA. Regarding the histopathological lesion, the infarct disturbed on the right side the lateral spinothalamic tract, nucleus of the spinal tract of the trigeminal nerve, spinal tract of the trigeminal nerve, spinocerebellar tract, inferior cerebellar peduncle and nucleus ambiguus. CONCLUSION: Based on our investigation of pathological lesions using our 2 autopsies, we suggest calling the cases that satisfy the following 3 criteria "definite pathologic Wallenberg syndrome": i) identifiable pathological obstruction of the PICA or VA; ii) infarction in the lateral MO based on PICA or VA obstruction; and iii) a 1-to-1 correspondence between clinical symptoms and neuropathological lesions.

Simple pathological examination technique for detection of cancer located at the surgical margin of the stomach.

BACKGROUND: The technique for examining surgical resection margins described in the Japanese Classification of Gastric Carcinoma is based on the examination of continuous infiltration by the primary tumor, and discontinuous lesions such as multiple cancers are not examined. However, examining lesions-particularly cancers-at the resection margins is important for the prevention of cancers in the remaining stomach that result from cancer remnants (remnant gastric cancer). METHODS: The clinical usefulness of a simple pathological examination technique for detecting cancer located at the surgical margin of the stomach was studied. A specimen 5-8 mm wide was resected from the surgical cut margin along the entire circumference of the stomach. When the pathological margin was positive for cancer, the surgical margin was also examined, and cases that were positive for cancer were regarded as marginally positive. RESULTS: Of the 1,498 patients with early gastric cancer who were examined using this method, 17 (1.1 %) were marginally positive for multiple cancers, and 8 of these 17 patients (57 %) had microcancers <5 mm in diameter. CONCLUSION: This method is simple and useful for detecting cancer involving the surgical margin, which occurs at a rate of 1.1 %, making it possible to prevent remnant gastric cancer by reoperation.

A preliminary study of preoperative chemotherapy combining irinotecan and cisplatin in patients with gastric cancer with unresectable para-aortic lymph node metastases.

BACKGROUND: A high response rate has been reported for chemotherapy combining irinotecan (CPT-11) and cisplatin (CDDP) against advanced gastric cancer. The strong anti-tumor activity of this regimen makes it very attractive as a preoperative chemotherapy. We conducted a preliminary study on preoperative chemotherapy with this regimen in patients with unresectable gastric cancer with para-aortic lymph node metastases to evaluate the feasibility of it as a treatment strategy. METHODS: Patients with unresectable para-aortic lymph node metastasis without distant hematogenous metastasis (H0, M0 and M1 LYM) and peritoneal dissemination (P0) were eligible for entry. The preoperative chemotherapy consisted of at least three cycles of CPT-11 (70 mg/m(2)) on days 1 and 15 and CDDP (80 mg/m(2)) on day 15, repeated every 4-6 weeks. Chemotherapy was followed by surgery with extended lymph node dissection in patients who achieved complete or partial responses and whose cancers were judged to be resectable. RESULTS: Six patients were entered into the study. In total, 18 cycles of chemotherapy were performed and five patients received at least three cycles. Objective partial responses were achieved in four patients. The major toxicities in the chemotherapy were neutropenia and diarrhea, but these were clinically acceptable. Four patients underwent surgery after the chemotherapy, and macroscopically complete resections with extended lymph node dissection were achieved in two patients. There were no therapy-related deaths. We found no pathological complete responses, but observed a definite histopathological effect caused by the chemotherapy in surgical specimens. The median survival time of all patients was 12 months. The longest survival without relapse is >6 years from the start of therapy. CONCLUSIONS: We conclude that preoperative chemotherapy with CPT-11/CDDP therapy is feasible in patients with advanced gastric cancer and that the regimen is safe when followed by surgery. Further clinical studies with larger numbers of patients are warranted to evaluate the efficacy of this strategy.