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Biomedical subjects

K Miwa

Publications and source records attributed to K Miwa.

At least 91 records · Page 5Linked to original sources

Significance of lysine/glycine cluster structure in gastric H+,K+-ATPase.

Gastric H+,K+-ATPase consists of alpha- and beta-subunits. The catalytic alpha-subunit contains a very unique structure consisting of lysine and glycine clusters, KKK(or KKKK)AG(G/R)GGGK-(K/R)K, in the amino-terminal cytoplasmic region. This structure is well conserved in all gastric H+,K+-ATPases from different animal species, and was postulated to be the site controlling the access of cations (or proton) to its binding site. In this report, we studied the role of this unique structure by expressing several H+,K+-ATPase mutants of the alpha-subunit together with the wild-type beta-subunit in HEK-293 cells. Even after replacing all the positively-charged amino acid residues (six lysines and one arginine) in the cluster with alanine or removing all the glycine residues in the cluster, the mutants preserved the H+,K+-ATPase activity, and showed similar affinity for ATP and K+ as well as similar pH profiles as those of wild-type H+,K+-ATPase, indicating that the cluster is not indispensable for H+,K+-ATPase activity and not directly involved in determination of the affinity for cation (proton).

Adenosine Triphosphate↗

Remnant-like particle cholesterol, triglycerides, and insulin resistance in nonobese Japanese type 2 diabetic patients.

OBJECTIVE: The aim of the study was to investigate the relationships between remnant-like particle (RLP) cholesterol, triglycerides, and insulin resistance in nonobese Japanese type 2 diabetic patients. RESEARCH DESIGN AND METHODS: A total of 86 nonobese Japanese type 2 diabetic patients (72 men and 14 women, aged 40-83 years, BMI 20.1-26.6 kg/m2) were studied. BMI, HbA1c levels, and fasting concentrations of plasma glucose, serum lipids (RLP cholesterol, total cholesterol, HDL cholesterol, and triglycerides), and serum insulin were measured. Insulin resistance was estimated by the homeostasis model assessment (HOMA-IR). The subjects were divided into two groups according to the value of HOMA-IR. Values >2.5 were indicative of the insulin-resistant state, and values <2.5 were indicative of the insulin-sensitive state. RESULTS: The insulin-resistant group had significantly higher RLP cholesterol and triglyceride levels and lower HDL cholesterol levels compared with the insulin-sensitive group. Univariate regression analysis showed that insulin resistance was positively correlated with BMI (r = 0.254, P = 0.019), HbA1c levels (r = 0.278, P = 0.011), RLP cholesterol levels (r = 0.315, P = 0.004), and triglyceride levels (r = 0.332, P = 0.002) and was negatively correlated with HDL cholesterol levels (r = -0.301, P = 0.006) in our diabetic patients. Multiple regression analysis showed that insulin resistance was independently associated with serum triglyceride levels, which explained 13.5% of the variability of insulin resistance in our nonobese Japanese type 2 diabetic patients. CONCLUSIONS: These results indicate that 1) nonobese Japanese type 2 diabetic patients with insulin resistance are characterized by high RLP cholesterol and triglyceride levels, and low HDL cholesterol levels; and 2) the level of serum triglycerides is an independent predictor of insulin resistance in these patients.

Apolipoproteins↗

Bilateral pleural effusion following cervical abscess drainage: a case report.

Postoperative bilateral chylothorax after cervical surgery has been rarely reported, whereas unilateral chylothorax has been occasionally reported after thoracic surgery. Here, we report a rare case of bilateral pleural effusion that developed after cervical abscess drainage. On the second day after the drainage, the patient felt dyspnea, and bilateral pleural effusion was found on a chest X-ray. The effusion was thought to be chyle and was successfully treated with conservative management. Additionally here, we have suggested that non-traumatic chylothorax was caused by increasing intraluminal pressure occurring inside the thoracic duct after its ligation. Careful follow up of any respiratory symptoms and of chest X-rays is recommended after cervical intervention.

Abscess↗

Thoracoscopic lung biopsy for diffuse infiltrative lung disease.

Thoracoscopic lung biopsy is becoming the procedure of first choice for the diagnosis of many localized and diffuse lung diseases. We have performed thoracoscopic lung biopsy for 17 patients with diffuse infiltrative lung disease, in Kurume University Hospital. There were 13 females and 4 males with a mean age of 48 years (range: 19-71 years). Thoracoscopic surgical biopsy was performed in the right lung in 12 and in the left lung in 5. Adequate lung tissue from each case was obtained for pathological examination. The mean surgical biopsy time was 49 min (range: 25-72 min) and bleeding was negligible. The mean duration for chest tube drainage was 2.6 days. No postoperative complication such as prolonged air leakage occurred. A specific diagnosis from the biopsy was achieved in 13 (76.4%) of the 17 cases. In only 6 (35.2%) of the 17 cases, the pathological diagnosis was the same as that from the thoracoscopic biopsy. In these 6 cases, the same diagnosis was obtained only in those with idiopathic interstitial pneumonitis or diffuse panbronchitis. Thoracoscopic lung biopsy was safe and useful for diagnosis for diffuse infiltrative lung disease.

Adolescent↗

Trypsinogen expression in colorectal cancers.

The purpose of this study was to evaluate the trypsinogen expression in human colorectal cancers. We observed the trypsinogen-1 mRNA expression in five of ten human colorectal cancer cell lines by reverse transcriptase-polymerase chain reaction (RT-PCR), and gelatinolytic activity in conditioned medium of cancer cells at acidic pH by gelatin zymography. Furthermore, trypsinogen protein expression was observed in 68 out of 154 (44.2%) surgical specimens of colorectal cancer immunohistochemically. However, there was no statistically significant relationship between the trypsinogen expression and the clinicopathological findings. These findings suggest that trypsinogen might be involved in cancer invasion and metastasis throughout the cancer progression.

Colorectal Neoplasms↗

N-ethylmaleimide-enhanced phosphatidylserine externalization of human pancreatic cancer cells and immediate phosphatidylserine-mediated phagocytosis by macrophages.

The purpose of this study was to examine whether N-ethylmaleimide (NEM) can enhance phosphatidylserine (PS) externalization on the outer surface of cancer cells, and PS-externalized cancer cells can be phagocytosed immediately by macrophages. NEM could externalize PS of cancer cells in concentration- and time-dependent manners. When treated with 5 mM NEM for 1 h, 80% of the carcinoma cells externalized their PS. In phagocytosis assay, these cells were engulfed immediately by macrophages before undergoing apoptosis. These results suggest that NEM can immediately externalize PS of cancer cells, leading to their recognition and phagocytosis by macrophages before undergoing apoptosis morphologically.

Animals↗

PPARgamma ligand (thiazolidinedione) induces growth arrest and differentiation markers of human pancreatic cancer cells.

The aim of this study was to examine whether a specific PPARgamma ligand can inhibit the growth of human pancreatic cancer cells through induction of terminal differentiation. PPARgamma was expressed in five human pancreatic cancer cell lines: Capan-1, AsPC-1, BxPC-3, PANC-1, and MIA PaCa-2. Treatment of these cells with a specific PPARgamma ligand, thiazolidinedione (TZD), resulted in inhibition of both cellular and clonogenic growth, and G1 cell cycle arrest. Finally, thiazolidinedione treatment resulted in induction of p21WAF-1 and increased expression of differentiation markers. These results suggest that thiazolidinedione treatment inhibits growth and induces cellular differentiation in pancreatic cancer cells and thereby reduces their development in favor of differentiated and stable cell phenotype.

Adenocarcinoma↗

[A case of stage IVb (H2P0N4T4) gastric cancer successfully treated with neoadjuvant chemotherapy (PMFE therapy)].

A 69-year-old man was examined at our hospital because of a sense of upper abdominal fullness. He was diagnosed as having stage IVb (H2P0N4T4) gastric cancer and treated with neoadjuvant chemotherapy. One course of the regimen consisted of 10 mg CDDP (day 1-5), 10 mg MMC (day 1), 250 mg 5-FU (day 1-20) and 50 mg ETP (day 6, 7). The patient underwent the regimen three times in succession. After the chemotherapy, his hepatic metastases showed necrotic changes and the swelling of the para-aortic lymph nodes disappeared on a CT scan. A histological examination revealed that the cancer cells had completely vanished both at the site of the hepatic tumor and the para-aortic lymph nodes. This combination chemotherapy, named PMFE therapy, is considered effective without serious side effects for gastric cancer in patients with non-curative factors.

Adenocarcinoma↗

[Sentinel node concept and its application for cancer surgery].

The sentinel node is the first lymph node that drains a primary tumor. A negative sentinel lymph node accurately predicts the absence of metastasis to any other regional lymph nodes. A higher rate of feasibility, sensitivity, specificity, and diagnostic accuracy in sentinel lymph node mapping has been demonstrated of cancer of the breast, penis, and vulva and in malignant melanoma. Intraoperative endoscopic lymphatic mapping, which we developed for gastric cancer in 1994, was also useful in accurately predicting nodal status in 163 early-stage gastric cancer patients: the rate of sensitivity, specificity, and accuracy was 91%, 100%, and 98%, respectively. Therefore if the sentinel lymph node biopsy is free of metastasis, limited surgery such as wedge resection, segmental resection, pylorus-preserving gastrectomy, or proximal gastrectomy is indicated. The tumor-free sentinel lymph node allows dissection of regional lymph nodes to be avoided and results in an improved quality of life in postoperative patients. In addition, sentinel lymph node biopsy has the advantages of enhancing staging accuracy, detecting micrometastases, and identifying variations in the regional lymphatic basin. Further progress may change the mode of nodal dissection and the indications for adjuvant chemotherapy for cancer.

Humans↗

[Sarcomatoid carcinoma of the urinary bladder: report of a case].

The patient was a 78-year-old man with gross hematuria. A non-papillary and non-pedunculated tumor was found on the posterior wall of the bladder by cystoscopic examination. Total cystectomy with construction of ileal conduit was performed. Histologically, the tumor was composed of carcinomatous and sarcomatous elements. The carcinomatous element was compatible with grade 3 transitional cell carcinoma. The sarcomatous element was composed of osteosarcomatous, chondrosarcomatous pattern and undifferentiated malignant spindle cell component. Immunohistochemical examination demonstrated the presence of keratin, cytokeratin and epithelial membrane antigen in both carcinomatous and sarcomatous elements. Therefore, we diagnosed this tumor as sarcomatoid carcinoma. The patient has remained well without any evidence of recurrence for 10 months after operation.

Aged↗

[Sentinel lymph node biopsy and axillary lymph node dissection].

Sentinel lymph node (SLN) biopsy is a useful way of assessing axillary status and obviating axillary dissection in patients with node-negative breast cancer. A combination of dye- and gamma probe-guided methods can identify SLN more accurately and easily than either of these techniques alone. On the other hand, SLN biopsy is highly accurate and sensitive in patients with small tumors, and no false-negative SLN biopsy has been reported for a breast cancer < 1.0-1.5 cm. Moreover, extensive intraoperative examination of SLNs using frozen sections can attain a sensitivity comparable to that obtained by histologic examination on the permanent sections. In practice, therefore, axillary dissection can be avoided in patients with small tumors in whom the SLNs are negative.

Axilla↗

[Small cell carcinoma of the urinary bladder: a case report].

We report a case of small cell carcinoma of the urinary bladder. The patient was a 58-year-old man complaining of gross hematuria. Clinical examination revealed a non-papillary, broad-based tumor on the right bladder wall with a clinical stage of T3a, N0, M0. Neoadjuvant intraarterial infusion chemotherapy with methotrexate, adriamycin and cisplatin was performed, but it was ineffective. Three weeks later we performed a radical cystectomy. The operative specimen of the tumor revealed small cell carcinoma. It was staged pT3aN0M0R0L2V1. Postoperatively, 1 course of adjuvant chemotherapy using cisplatin and etoposide was performed. The patient is alive without any evidence of tumor recurrence at 6 months after operation.

Antineoplastic Combined Chemotherapy Protocols↗

[An effective case of hepatic arterial infusion chemotherapy based on biochemical modulation for hepatic recurrence of non-functioning islet cell carcinoma of the pancreas].

A 55-year-old man had a metastasis in segment 3 of the liver 5 months after surgery for non-functioning islet cell carcinoma of the pancreas. The metastatic lesion increased in size in a short period, and other liver micro-metastases that could not be detected by imaging may exist, so hepatic arterial infusion chemotherapy was scheduled for 3 months. The patient underwent hepatic arterial infusion chemotherapy of 5-fluorouracil (250 mg/day/body for 5 days/week) and adriamycin (10 mg/day/body for 2 days/week) and cisplatin (10 mg/day/body for 5 days/week) and he was put on Leucovorin 30 mg/day as a biochemical modulator of 5-FU and tamoxifen 40 mg/day as a biochemical modulator of ADM. A total 6,000 mg of 5-FU, 100 mg of ADM and 240 mg of CDDP had been administered, until hepatic arterial infusion chemotherapy was discontinued because of complicated gastric ulcer. Three months later, the size of the metastatic liver tumor was reduced remarkably and no other metastasis was detected on CT scan, so he underwent partial hepatectomy of the metastatic lesion. No recurrence was found and he has survived in good physical condition during the follow-up period of 5 months after the second operation.

Administration, Oral↗

[A case of a combined aortectomy with dissection of recurrent paraaortic lymph nodes of sigmoid colon cancer].

A combined aortectomy was performed on a patient with recurrence of sigmoid colon cancer in the paraaortic lymph nodes. The 48-year-old woman was found to have tumor recurrence in the lymph nodes in the area between the aortic bifurcation and the paraaortic area, accompanied by left hydronephrosis, four years after surgery for sigmoid colon cancer (H0, P0, ss, n3, stage IIIb). No metastasis to distant areas was detected at that time. The woman thus underwent a reoperation. Intraoperatively, the aortic bifurcation and the lymph nodes were seen as a mass. The mass involved the left common iliac vein and the left ureter, as well. Therefore, we resected the area from the aortic bifurcation to the bilateral common iliac arteries, the left common iliac vein, the left ureter and the left kidney en bloc, and replaced them with a Y-shaped graft. One year after the reoperation, a tumor metastasis to the liver was detected, and a partial hepatectomy was performed. At present, the patient is being managed at our outpatient clinic. The results suggest that extended resection, involving the aorta as well, is sometimes useful when dealing with tumor recurrence in the paraaortic lymph nodes, unaccompanied by blood-borne metastasis.

Aorta↗

Activation of matrix metalloproteinase-2 in human breast cancer cells overexpressing cyclooxygenase-1 or -2.

Human breast cancer cell line Hs578T was stably transfected with cDNA for cyclooxygenase-1 or -2. When the cells overexpressing cyclooxygenase-1 or -2 were stimulated with concanavalin A, the processing of matrix metalloproteinase-2 was observed with the aid of gelatin zymography. This processing was not seen in mock-transfected and original cells which did not express detectable cyclooxygenase activity. Furthermore, Northern blotting showed 8-13 fold induction of membrane-type 1 matrix metalloproteinase which processed matrix metalloproteinase-2 in the cells expressing cyclooxygenases. These findings suggest that both isoforms of cyclooxygenase mediate the processing of matrix metalloproteinase-2 through induction of membrane-type I metalloproteinase in breast cancer cells.

Breast Neoplasms↗