Biomedical subjects

K Kurozumi

Publications and source records attributed to K Kurozumi.

At least 19 recordsLinked to original sources

PubMed2006

Importance of lymph vessels in gastric cancer: a prognostic indicator in general and a predictor for lymph node metastasis in early stage cancer.

BACKGROUND: Metastasis to regional lymph nodes (LNs) through lymphatic vessels is common in cancer progression and is an important prognostic factor in many cancers. Recent evidence suggests that tumour lymphangiogenesis promotes lymphatic metastasis. AIMS: To study the role of lymph vessel density (LVD) in gastric cancer and investigate whether LVD is associated with LN metastasis/prognosis. METHODS: Lymphatics of 117 primary human gastric cancer cases were investigated by quantitative immunohistochemical staining for podoplanin. The relation between LVD and LN metastasis and other established clinicopathological parameters was analysed. The relation between LVD and prognosis was also studied. RESULTS: Mean LVD of "hot spots" was 11.6/case. LVD significantly correlated with LN and podoplanin positive lymphatic invasion. High LVD was associated with worse overall survival. In multivariate analysis, positive LVD was a significant independent predictor of overall survival, depth of invasion, and TNM stage. LVD significantly correlated with LN metastasis at surgery and podoplanin positive lymphatic invasion. In multivariate analysis, positive LVD was an independent significant predictor of LN metastasis. CONCLUSIONS: Increased podoplanin expression is significantly associated with LN metastasis, and may play an important role in detecting LN metastasis in gastric cancer. Furthermore, LVD may be a significant prognostic factor in gastric cancer at any stage. In addition, LVD and lymph vessel invasion detected by podoplanin immunohistochemistry are associated with LN metastasis in T1 early gastric cancer. LVD assessment by podoplanin immunohistochemistry may become a useful predictor of LN metastasis in T1 early gastric cancer and may influence the decision making process for additional surgery.

Biomarkers, Tumor↗

PubMed2004

Antitumor effect of genetically engineered mesenchymal stem cells in a rat glioma model.

The prognosis of patients with malignant glioma is extremely poor, despite the extensive surgical treatment that they receive and recent improvements in adjuvant radio- and chemotherapy. In the present study, we propose the use of gene-modified mesenchymal stem cells (MSCs) as a new tool for gene therapy of malignant brain neoplasms. Primary MSCs isolated from Fischer 344 rats possessed excellent migratory ability and exerted inhibitory effects on the proliferation of 9L glioma cell in vitro. We also confirmed the migratory capacity of MSCs in vivo and showed that when they were inoculated into the contralateral hemisphere, they migrated towards 9L glioma cells through the corpus callosum. MSCs implanted directly into the tumor localized mainly at the border between the 9L tumor cells and normal brain parenchyma, and also infiltrated into the tumor bed. Intratumoral injection of MSCs caused significant inhibition of 9L tumor growth and increased the survival of 9L glioma-bearing rats. Gene-modification of MSCs by infection with an adenoviral vector encoding human interleukin-2 (IL-2) clearly augmented the antitumor effect and further prolonged the survival of tumor-bearing rats. Thus, gene therapy employing MSCs as a targeting vehicle would be promising as a new therapeutic approach for refractory brain tumor.

Adenoviridae↗

PubMed2002

Relation between ultrasonographic and histologic findings of tracheal invasion by differentiated thyroid cancer.

Between 1988 and 1999 a total of 24 patients with differentiated thyroid cancer invading the airway underwent various types of tracheal resection at the Osaka Police Hospital. Preoperative ultrasonographic (US) findings in these patients were compared with postoperative histologic results of the resected specimens to confirm the relation between the preoperative and postoperative diagnoses and to determine the indications for operative procedures. Preoperative US revealed cancer invasion to the adventitia in 2 cases, to the intercartilage space in 13, and to the tracheal mucosa in 9. Histologically, cancer invasion to the adventitia was confirmed in 4, to the intercartilage space in 10, and to the mucosa in 10. Among 13 cancer invasion instances to the intercartilage revealed by US, overdiagnosis occurred in 3 cases and underdiagnosis in 1. The actual overall diagnostic rate by US was 83.3%, which is a great improvement over other available methods. In conclusion, preoperative US findings of the trachea agreed with the histologic findings of the resected specimens, indicating US to be the first choice when making decisions about resecting the trachea and about the operative procedure.

Carcinoma, Papillary↗

PubMed2001

Merits and demerits of operative procedure to the trachea in patients with differentiated thyroid cancer.

Local radical thyroidectomy, including cervical lymph node dissection and combined circumferential resection of the trachea, has been performed over the past 20 years in 31 patients with differentiated cancer invading the trachea. The 5- and 10-year survival rates for these patients were 77.4% and 66.7%, respectively. In 19 of the 31 (61%) cases the recurrent nerve was resected because of direct cancer invasion. Bilateral recurrent nerve palsy occurred in 12 patients, 3 of whom were managed postoperatively using a T-shaped tube for preservation of the larynx. Hoarseness remained in 21 patients. In two patients with recurrent cancer invasion of the larynx, partial laryngectomy and hemilaryngectomy were performed, and reconstruction was done using ear cartilage without postoperative dyspnea or dysphagia. Parathyroid function is an important factor in regard to the quality of life of patients. In 22 patients at least one of the parathyroids was preserved. Postoperative calcium administration was necessary in 14 patients. Our long-term observations indicate that local radical thyroidectomy with combined resection of the trachea can serve as a useful treatment for advanced differentiated cancer invading the airway.

Adult↗

PubMed2001

Experience with the high occipital transcortical approach in the treatment of intraventricular hemorrhage. Report of two cases.

Two patients with intraventricular hemorrhage (IVH) were treated by direct removal of their intraventricular hematomas via a high occipital transcortical approach with successful results. This approach lies between the parietooccipital transcortical approach and the occipital transcortical approach. The patients were a 90-year-old woman with idiopathic IVH and a 60-year-old man with hemorrhage caused by bleeding in the thalamus. In both cases, the hematoma was tightly packed in the lateral ventricle. In the former case, the inferior horn of the lateral ventricle was extremely swollen, and the patient was at risk for development of uncal herniation. With the goals of complete elimination of the hematoma in the inferior horn and identification of the source of bleeding, a high occipital transcortical approach was applied, and the hematoma was removed under direct vision. With the patient in the lateral position, a minor craniotomy of approximately 3 cm was performed around the puncture site of the posterior horn (8 cm craniad from the inion and 3 cm lateral from the midline). A 1-cm cortical incision was made and the posterior horn was reached. First, the portion of hematoma at this site was removed, and then the remainder was completely removed from the interior horn and corpus. Using this method, the entire region of the lateral ventricle, including the inferior horn, corpus, and posterior horn, can be covered in a single operative field, and it is also possible to have sufficient working space for the operation.

Aged↗

PubMed2000

Epstein-Barr virus-encoded poly(A)(-) RNA supports Burkitt's lymphoma growth through interleukin-10 induction.

Akata and Mutu cell lines are derived from Burkitt's lymphoma (BL) and retain the in vivo phenotype of Epstein-Barr virus (EBV) expression that is characterized by expression of EBV-determined nuclear antigen 1 (EBNA1), EBV-encoded RNAs (EBERs) and transcripts from the BAM:HI A region (BARF0). We found that EBV-positive Akata and Mutu cell clones expressed higher levels of interleukin (IL)-10 than their EBV-negative subclones at the transcriptional level. Transfection of an individual EBV latent gene into EBV-negative Akata cells revealed that EBERs were responsible for IL-10 induction. Recombinant IL-10 enabled EBV-negative Akata cells to grow in low (0.1%) serum conditions. On the other hand, growth of EBV-positive Akata cells was blocked by treatment either with an anti-IL-10 antibody or antisense oligonucleotide against IL-10. EBV-positive BL biopsies consistently expressed IL-10, but EBV-negative BL biopsies did not. These results suggest that IL-10 induced by EBERs acts as an autocrine growth factor for BL. EBERs, EBER1 and EBER2, are non-polyadenylated RNAs and are 166 and 172 nucleotides long, respectively. The present findings indicate that RNA molecules could regulate cell growth.

Burkitt Lymphoma↗

PubMed1999

Oncogenic role of Epstein-Barr virus-encoded RNAs in Burkitt's lymphoma cell line Akata.

Our previous reports indicated that Epstein-Barr virus (EBV) contributes to the malignant phenotype and resistance to apoptosis in Burkitt's lymphoma (BL) cell line Akata (N. Shimizu, A. Tanabe-Tochikura, Y. Kuroiwa, and K. Takada, J. Virol. 68:6069-6073, 1994; J. Komano, M. Sugiura, and K. Takada, J. Virol. 72:9150-9156, 1998). Here we report that the EBV-encoded small RNAs (EBERs) are responsible for these phenotypes. Transfection of the EBER genes into EBV-negative Akata clones restored the capacity for growth in soft agar, tumorigenicity in SCID mice, resistance to apoptotic inducers, and upregulated expression of bcl-2 oncoprotein that were originally retained in parental EBV-positive Akata cells and lost in EBV-negative subclones. This is the first report which provides evidence that virus-encoded RNAs (EBERs) have oncogenic functions in BL cells.

Animals↗

PubMed1998

Expression of CD44 variant 6 and lymphatic invasion: importance to lymph node metastasis in gastric cancer.

Lymph node metastasis is a critical prognostic factor for gastric cancer. In the present investigation we examined clinicopathologic factors influencing the metastatic processes to the lymph mode and their prognostic importance. A randomly selected group of 98 patients with adenocarcinomas of the stomach who underwent gastrectomy plus systematic lymph node dissection at Osaka Police Hospital from 1991 to 1996 were analyzed. Altogether 37 (38%) cancers were positive for CD44 variant 6 (v6) staining, 31 (32%) were intermediately stained, and 30 (30%) were negative. CD44-v6 expression correlated well with lymph node metastasis. Expression of CD44-v6 and lymphatic invasion were independent risk factors for metastatic lymph nodes. Among the patients with CD44-v6-positive and lymphatic invasion-positive cancers, 88% had lymph node metastasis, whereas only 13% of patients negative for both factors had lymph node metastasis. Although CD44-v6 expression and lymphatic invasion have been reported to be risk factors for recurrence and a poor prognosis, in this investigation these factors were found not to be significant for hematogenous and lymphatic recurrences or overall survival rates. Thus expression of CD44-v6 and lymphatic invasion may regulate lymph node metastases from gastric cancer.

Adenocarcinoma↗

PubMed1998

Significance of biologic aggressiveness and proliferating activity in papillary thyroid carcinoma.

Papillary thyroid carcinoma is a frequent thyroid cancer. Many factors have been reported to be of prognostic importance, but the significance of biologic factors suggesting aggressiveness and proliferating activity has not been sufficiently documented. Conventional prognostic factors such as age, extrathyroidal invasion, lymph node and distant metastasis, and biologic factors including histologic differentiation, DNA ploidy, S-phase and G2M-phase fractions, and expression of CD44 variant 6 (CD44-v6) obtained from 131 patients who underwent surgery for papillary thyroid carcinoma at Osaka Police Hospital were analyzed retrospectively. Age was closely related to extrathyroidal invasion, G2M-phase fraction, and CD44-v6 expression. Extrathyroidal invasion was independently related to age, gender, and lymph node metastasis. The grade of lymph node metastasis was related to extrathyroidal invasion, gender, distant metastasis, and CD44-v6 expression. Distant metastasis was associated with aneuploid tumors. Cause-specific survival was independently related to biologic factors including extrathyroidal invasion, distant metastasis, DNA ploidy and S-phase fraction. These results suggest that biologic factors indicating aggressiveness and proliferating activity are important for papillary thyroid carcinoma.

Aged↗

PubMed1998

BRAM1, a BMP receptor-associated molecule involved in BMP signalling.

BACKGROUND: TGF-beta superfamily members elicit signals through the stimulation of serine/threonine-kinase receptors. Recently, molecules associated with several TGF-beta family receptors have been cloned. One such molecule, the immunophilin FKBP12, has been reported to interact with TGF-beta family type I receptors. However, the identity of signalling specific molecules interacting with the receptor was unknown. RESULTS: To clarify the factors mediating bone morphogenetic protein (BMP) receptor signalling, a cytoplasmic molecule associated with the BMP type IA receptor (BMPR-IA) was isolated using the yeast two-hybrid system. We designated the molecule BMP receptor associated molecule 1 (BRAM1). BRAM1 is an alternatively spliced form of BS69, a factor previously identified as an adenovirus E1A-associated protein. BRAM1 was localized to the cytoplasmic region in mammalian cells, whereas BS69 is localized to the nucleus. BRAM1 bound specifically to BMPR-IA in mammalian cells. The C-terminal half of BRAM1 was found to be sufficient for binding to BMPR-IA. CONCLUSIONS: BRAM1, a BMPR-IA associated molecule, was isolated using the yeast two-hybrid system, and found to associate specifically with BMPR-IA. BRAM1 may thus serve as an interacting protein in the BMP signal pathway.

Adaptor Proteins, Signal Transducing↗

PubMed1997

Preservation of recurrent laryngeal nerve invaded by differentiated thyroid cancer.

OBJECTIVE: This study was undertaken to determine whether the recurrent laryngeal nerve involved in differentiated thyroid carcinoma could be preserved. SUMMARY BACKGROUND DATA: Few investigations have provided definitive results concerning preservation of the recurrent laryngeal nerve involved in thyroid cancer. Complete excision with resection of the recurrent laryngeal nerve reportedly did not improve survival over incomplete excision in differentiated thyroid carcinoma. METHODS: A retrospective study was performed with the medical records of 50 patients with differentiated carcinoma and preoperative normal vocal cord function to investigate outcomes of recurrent laryngeal nerve preservation including local recurrence, prognosis, and postoperative vocal cord function. The recurrent laryngeal nerves on 1 or both sides were preserved in 23 patients (the preserved group), whereas the involved recurrent laryngeal nerve of the other 27 patients was resected (the resected group). RESULTS: Backgrounds of patients were similar between the resected and preserved groups. The number of patients with recurrences in each group was similar, and incidence of local, regional, and distant metastatic recurrences were not different between the groups. Postoperative overall survival of the preserved group was similar to that of the resected group (p = 0.1208). More than 60% of patients or of nerve at risk in the preserved group restored normal vocal cord function within 6 months. Some functional vocal cord movement was recognized in 80% of patients or of nerve at risk. All patients in the resected group including patients with nerve anastomosis showed permanent paralysis of the ipsilateral vocal cord. CONCLUSIONS: These results suggested that the recurrent laryngeal nerve, even if infiltrated by differentiated thyroid cancer, is worthwhile to preserve for maintenance of postoperative vocal cord function without affecting the incidence of local recurrence or prognosis.

Adenocarcinoma, Follicular↗

PubMed1996

Predominant expression of a receptor tyrosine kinase, TIE, in hematopoietic stem cells and B cells.

A receptor tyrosine kinase (RTK), TIE (tyrosine kinase that contains immunoglobulin-like loops and epidermal growth factor [EGF] homology domains), is expressed in vascular endothelial and hematopoietic cells. We generated monoclonal antibodies (MoAbs) against the extracellular domain of TIE and a polyclonal antibody against the TIE carboxyterminus and used them to analyze expression of TIE in hematopoietic cells. Western blotting detected two forms of TIE protein with a molecular mass of 135 and 130 kD in hematopoietic and endothelial cells. Northern blotting analysis revealed that TIE was expressed preferentially in undifferentiated cell lines, especially when megakaryocytic, but not erythroid differentiation was induced. Reverse transcriptase-polymerase chain reaction (RT-PCR) showed that TIE was predominantly expressed in the human hematopoietic progenitor fraction, CD34+ cells. Fluorescence-activated cell sorting (FACS) showed that 42% of CD34+ and 17% of KIT-positive (KIT+) cells were TIE-positive (TIE+). The majority (81%) of the primitive hematopoietic stem cells, CD34+CD38- cells, were TIE+. Assays of progenitor cells and long-term culture-initiating cells (LTC-IC) showed that the TIE+ fraction contained more primitive cells than the TIE- fraction. Some TIE+ cells were in the CD34- fraction, which were CD19+ and CD20+ (B cells). These findings indicate that TIE has a unique spectrum of expression in primitive hematopoietic stem cells and B cells. Although its ligand has not been identified, TIE and its ligand may establish a novel regulatory pathway not only in early hematopoiesis, but also in the differentiation and/or proliferation of B cells.

Animals↗

PubMed1993

The solitary cutaneous metastasis of asymptomatic colon cancer to an operative scar.

Although umbilical or cutaneous metastases from asymptomatic internal malignancies are occasionally documented, the literature contains no report of a solitary cutaneous metastasis to an old operative scar from an asymptomatic internal malignancy. A rare case of colonic cancer presenting as a solitary subcutaneous metastasis to a lower abdominal scar resulting from an open prostatectomy is described in this communication. It was impossible to distinguish this subcutaneous metastasis from a pyogenic granuloma caused by residual sutures without histological evidence. Thus, a granuloma that persists despite repeated treatment may be a possible sign of asymptomatic internal malignancy.

Adenocarcinoma↗

PubMed1993

[Single-stage management of postoperative sternal wound infection using a pectoral musculocutaneous flap].

Two patients with postoperative sternal wound infection were successfully treated by a pectral musculocutaneous flap. A single-stage procedure of debridement and immediate closure with a pectral musculocutaneous flap can eliminate irrigation, open wound management, or reoperation for closure. Therefore, this method is very safe, simple, and effective for the management of sternal wound infections.

Aged↗

PubMed1992

Multivessel coronary revascularization with bilateral internal thoracic artery grafts.

Sixteen patients underwent coronary revascularization with bilateral internal thoracic artery (ITA) grafts between 1988 and 1989 at the Okayama University Hospital. A total 39 coronary grafts were performed, being an average of 2.4 grafts per patient. Each patient received bilateral ITA grafts, and in 5 patients an additional 7 grafts were constructed with 5 autologous veins and 2 gastroepiploic arteries. The right ITA was grafted as a free graft in 4 patients. The ITA graft patency rate was 96.8 per cent (31/32) at the time of hospital discharge. The postoperative morbidity included one reoperation for bleeding and one myocardial infarction. Coronary artery bypass grafting with bilateral ITA grafts can be safely performed and its application facilitates complete revascularization with arterial grafts.

Aged↗

PubMed1992

[Two cases of severe ischemic mitral regurgitation treated with CABG alone].

We report here two cases in which patients fell into pulmonary edema due to ischemic mitral regurgitation (ischemic MR) after cardiac catheterization and underwent emergency coronary artery bypass grafting (CABG) using an intra-aortic balloon pumping. The patient were a 65-year-old man and a 80-year-old woman, and both had a chief complaint of angina after myocardiac infarction. In both cases, coronary angiography revealed triple vessel disease, and left ventriculography showed severe MR. However echocardiography, when they were hospitalized, did not show significant MR. Therefore we thought that they had gone into congestive heart failure because cardiac ischemia and volume load following cardiac catheterization provoked MR. In fact, postoperative left ventriculography and echocardiography showed decreased MR. We now think that it is important to keep in mind the cases of severe ischemic MR for which CABG alone is adequate treatment and to evaluate ischemic MR not only by left ventriculography but also by echocardiography.

Aged↗

PubMed1992

[Traumatic rupture of the diaphragm--a case of lung herniation into the abdominal cavity].

A first case of lung herniation into abdominal cavity with traumatic diaphragmatic rupture is described. A 41-year-old Japanese man with chronic obstructive pulmonary disease suffered traumatic diaphragmatic rupture. He needed to get continuous mandatory ventilation for a long time. At the time of operation, left lung herniation into the abdominal cavity was observed. When those who have chronic obstructive pulmonary disease suffered thoraco-abdominal injury, we should take care that pulmonary herniation might exist.

Abdomen↗

PubMed1991

[Operation of coronary artery aneurysm after previous coronary artery bypass grafting].

A 43-year-old male, who had undergone coronary artery bypass grafting 11 years ago, developed exertional chest pain. Selective coronary angiograms revealed severe stenosis and a large aneurysm in the obtuse marginal branch of the circumflex coronary artery. Previous grafts to the left anterior descending coronary artery and diagonal branch were patent. Ligation of the aneurysm and internal mammary artery grafting were performed through a left anterolateral thoracotomy. This approach made it easy to reach the aneurysm and to minimize bleeding during dissecting the adhesions. The patient had an uncomplicated postoperative course, and postoperative coronary angiograms revealed an obstructed aneurysm and a patient internal mammary artery graft. He has done well without recurrence of symptoms.

Adult↗