Biomedical subjects

K Kawamoto

Publications and source records attributed to K Kawamoto.

At least 55 records · Page 3Linked to original sources

PubMed1999

Possible paracrine mechanism of insulin-like growth factor-2 in the development of liver metastases from colorectal carcinoma.

BACKGROUND: Insulin-like growth factor-2 (IGF-2) is considered one of the autocrine growth factors in colorectal carcinoma. In addition, it is well known that IGF-2 is produced in the liver. However, the role of IGF-2 in liver metastasis is not yet understood clearly. METHODS: Immunohistochemical staining of IGF-2 and IGF-1 receptor (IGF-1R) was performed on tissue samples of liver metastases from 30 colorectal carcinoma patients. In situ hybridization of IGF-2 also was conducted on the same tissue samples. Furthermore, proliferating cell nuclear antigen (PCNA) was immunohistochemically stained for use as an indicator of the proliferative activity of cancer cells. RESULTS: Invasive margins of liver metastases were stained highly by both IGF-2 (70%) and IGF-1R (83%). Overexpression of IGF-2 protein and mRNA was observed in the normal liver adjacent to the tumor. The PCNA labeling indices (LIs) of the IGF-2 positive groups were significantly higher than those of the IGF-2 negative group (P < 0.0001). In addition, the PCNA LIs for the IGF-1R positive groups also were significantly higher than those for the IGF-1R negative group (P=0.0002). CONCLUSIONS: These findings suggest that hepatocyte-derived IGF-2 stimulates tumor cell proliferation by a paracrine mechanism and plays an important role in tumor progression in colorectal carcinoma patients with liver metastases.

Aged↗

PubMed1999

Bioaccumulation of rare earth elements in cultured HeLa cells.

HeLa S-3 cells were grown in minimal essential medium supplemented with 10% calf serum and 1 mM L-glutamine without adding any rare earth elements (REEs). Exponentially growing cells were collected, and dried materials were used to analyze their REE content by inductively coupled plasma-mass spectrometry. The results showed that the cells accumulated REEs in individually different manners; namely the accumulation ratio was higher in the lighter REEs than in the heavier REEs. To deduce the implication of the accumulation of REEs in HeLa cells, the accumulation ratios for REEs were compared with those of other biologically important elements. It was seen that the accumulation ratios obtained for REEs (from 31.8 [Ce] to 14.7 [Lu]) were intermediate among those of many bioelements: Fe (124), Mg (54.5), K (38.8), Cr (12.7), Na (11.8), Mn (11.3), Zn (10.7), Ca (8.8), and V (6.7).

Culture Media↗

PubMed1999

Catastrophic failure of cementless total hip arthroplasty using a femoral component without surface coating.

Consecutive series of 90 hips that had had a primary cementless arthroplasty with use of straight collarless stems between January 1988 and September 1992 were reviewed. Twenty-eight hips with Omnifit Normalized Stems (Fit-N) and 45 hips with Omniflex Normalized Stems (Flex-N) without porous coatings were compared clinically and radiographically with 17 hips with Omnifit Microstructured Stems (Fit-M) with porous coating. The average follow-up periods for the 3 stems were 97 months, 73 months, and 93 months. Revision was performed or awaited in 9 cases (32.1%) in the Fit-N group, 18 cases (40.0%) in the Flex-N group, and 1 case (5.8%) in the Fit-M group. The average annual subsidence was 0.62 mm/y, 0.73 mm/y, and 0.17 mm/y. Osteolysis of more than 3 mm occurred in 28.6%, 37.8%, and 23.5%. Fit-N stems and Flex-N stems without porous coatings are not appropriate for cementless total hip arthroplasty.

Bone Cements↗

PubMed1999

Non-Hodgkin lymphoma and coexisting primary cancers: a retrospective clinical analysis of 10 patients.

The simultaneous occurrence of non-Hodgkin lymphoma (NHL) and primary cancers is rare, and the treatment strategy for both malignancies is unclear. The authors analyzed the clinical records of 10 patients with NHL and coexisting primary cancers. All patients initially had symptoms of NHL, and all carcinomas were found at the initial workup of NHL by chance. The most common primary sites of coexisting cancers were the stomach (six patients) and the colon (two). Histologically, the majority of NHLs were intermediate grade, and all lesions were B-cell type. All primary cancers were adenocarcinoma. Initially, NHL was treated with radiotherapy or chemotherapy. Six primary cancers were resected surgically or endoscopically after the remission of NHL. The remaining four patients received no treatment for primary cancers because of advanced stages or early relapse of NHL. Three patients died of NHL, one died of cancer, and six were still alive, five without evidence of disease and one with disease. The authors conclude that early detection of a coexisting cancer and appropriate treatment after the remission of NHL may increase the possibility of a cure.

Adenocarcinoma↗

PubMed1999

Correlation of tensile strength with bursting pressure in the evaluation of intestinal anastomosis.

BACKGROUND: Although bursting pressure and tensile strength have long been measured to evaluate anastomotic techniques, it has yet to be clarified whether or not they are correlated, what implications they have, and which should be used as a gold standard. MATERIAL AND METHODS: Using an experimental model to estimate pressure and tension in the same colonic anastomosis, the following variables were measured in 48 rats between days 0 and 14: bursting pressure (BP); minimal tensile strength (MITS) necessary to break a part of the anastomosis, and maximal tensile strength (MATS) needed to disrupt the whole anastomosis. Also, circulatory wall tension (CWT) was derived from BP and the anastomotic circumference (AC), and longitudinal wall tension (LWT) from MITS and AC. These variables were compared using correlation and regression analysis. RESULTS: During the lag phase (days < or = 4) there was poor correlation between pressure-related and tension-related variables whereas highly significant correlations were noted in the subsequent fibroplastic phase (day > or = 5). It was shown by regression lines that positive MITS and MATS were expected when BP was zero. CONCLUSION: Contrary to the previous assumption, no correlation was found between BP and tensile strength in the critical postoperative period. Based on our present and previous studies, measurement of MITS is recommended to evaluate the healing of colonic anastomosis.

Anastomosis, Surgical↗

PubMed1999

[Anesthetic management of a patient with Ludwig's angina].

A 71-year-old woman with cellulitis of the floor of the mouth, referred to as "Ludwig's angina", underwent emergency tracheostomy under general anesthesia, for the control of airway narrowing caused by sublingual and submandibular swelling with tongue elevation. Because difficult airway had been suspected by preoperative assessment, feasible options of intubation in our hospital, including laryngeal mask, fiberoptic intubation and transtracheal jet ventilation, were prepared prior to induction of anesthesia. Anesthetic induction was carried out with propofol and suxamethonium, and subsequently tracheal intubation could be performed with difficulty under condition of partial visualization of vocal cord. Anesthetic maintenance with local anesthesia and continuous infusion of propofol 6 mg.kg-1.hr-1 was carried out during tracheostomy procedure, and this procedure was done uneventfully. Because airway control still remains a top priority in Ludwig's angina, feasible options of airway control should be prepared before induction of anesthesia if tracheostomy was required in a patient with this disease.

Aged↗

PubMed1998

Colcemid-induced apoptosis of cultured human glioma: electron microscopic and confocal laser microscopic observation of cells sorted in different phases of cell cycle.

The effect of the antitubulin agent colcemid on human glioma cells was investigated by sorting cells with different DNA content and subjecting them to confocal laser microscopy and transmission electron microscopy. The human glioma cell line U251MG was exposed to colcemid at a concentration of 0.05 microg for 16 h. Flow cytometric analysis revealed the accumulation of cells in S/G2M phase. Cells harvested from each of G0/G1 and S/G2M peaks were then analyzed by confocal laser microscopy and transmission electron microscopy. Confocal laser microscopy revealed that colcemid-treated cells harvested from the G0/G1 peak contained mitotic and apoptotic cells in addition to interphase cells. Electron microscopy confirmed that colcemid-treated cells in the G0/G1 peak had fragmented nuclei typical of apoptotic cells and mitotic cells with altered chromatin structure. Some mitotic cells obtained by mitotic shake-off after treatment with colcemid showed DNA strand breaks defined by in situ nick end labeling. The present study indicates that mitotic as well as interphase apoptosis occurs in U251MG cells following colcemid treatment.

Apoptosis↗

PubMed1998

IL-12 reverses established antigen-specific tolerance of contact sensitivity by affecting costimulatory molecules B7-1 (CD80) and B7-2 (CD86).

Cutaneous painting with reactive haptens induces contact sensitivity (CS) responses that are in vivo examples of T cell immunity. In contrast, high dose i.v. administration of the hapten can induce tolerance. We investigated the effect of IL-12 on reversal of this tolerance and attempted to determine in vitro the mechanism of this reversing effect by measuring proliferation and IFN-gamma production by CS effector T cells stimulated with hapten-conjugated APC, and we also measured CS ear swelling in vivo. The in vitro responses of T cells to hapten-APC became absent in tolerized mice, paralleling impaired in vivo CS responses. Addition of IL-12 to cultures manifesting this fully established in vitro tolerance completely restored impaired responses of tolerized T cells. The reversing effects of IL-12 were not blocked by anti-IFN-gamma mAb, but were blocked by mAbs against B7-1, more strongly by anti-B7-2, and by both Abs together. Additional in vivo ear-swelling response experiments confirmed the reversing effects of IL-12 on established tolerance. To examine whether the IL-12 effect depended on stimulation of IFN-gamma, we directly injected IFN-gamma into tolerized mice. This partially mimicked but did not fully reconstitute the effects of IL-12. In summary, IL-12 abrogation of established tolerance of CS may have been partially due to endogenous production of IFN-gamma, but appeared mainly due to direct activation of the tolerized T cells by affecting signaling through costimulatory molecules B7-1 and B7-2.

Animals↗

PubMed1998

Enhanced expression in seminoma of human zinc finger genes located on chromosome 19.

Six Krüppel-type zinc finger (ZF) genes were cloned from a seminoma cDNA library. One, ZFS-1, showed high sequence homology to the ZNF91 KRAB (Krüppel-associated box) ZF gene family and also the same chromosomal assignment. Interestingly, Northern blot analyses using ZFS-1 and ZNF91 revealed that multiple ZF genes on chromosome 19 were predominantly expressed in seminomas. In addition, the testis and the seminoma showed specific expression of 2.3 kb transcript. Our results suggest that ZF genes on chromosome 19 may be implicated in the development and/or growth of seminomas.

Amino Acid Sequence↗

PubMed1998

Natural history of colorectal carcinoma: can the tumor volume doubling time be predicted by radiologic findings or immunohistochemical variables?

BACKGROUND AND OBJECTIVES: The factors influencing the growth rate of colorectal carcinoma have not been determined. The aim of this study was to clarify the relationship between the doubling time (DT), morphology, and proliferating cell nuclear antigen, Ki-67 and p53 immunohistochemistry in colorectal carcinoma. METHODS: Thirty-three patients (37 lesions) were studied retrospectively. The DT was calculated and correlated with the initial and final tumor size, morphologic shape, and immunohistochemical results. RESULTS: The DT ranged from 2.4 to 48.0 months (mean: 12.0 months). The mean DT of the early-stage carcinomas was significantly longer than that of the advanced carcinomas. In the latter group, both slowly growing and rapidly growing tumors were observed. The DT showed no correlation with the initial or final size and shape of the tumors on radiographs, or with the immunohistochemical results. CONCLUSIONS: Our data revealed that it is not possible to evaluate the growth rate of colorectal carcinomas based on their morphological shape, cellular proliferative activity, or tumor suppressor gene activity.

Adenocarcinoma↗

PubMed1998

Kimura's disease of the lacrimal gland.

A 33-year-old Japanese woman had bilateral eyelid swelling and soft tumor of the right orbit. Increased serum IgE and eosinophilia in the peripheral blood was observed. Magnetic resonance imaging of the lesion showed hypointense orbital fat on T1-weighted image and isointense orbital fat on T2-weighted image. Gd-DTPA T1-weighted images demonstrated marked enhancement. The histopathological appearance of the tumor was consistent with Kimura's disease. On a regimen of 60 mg of prednisone per day, the orbital mass reduced in size. A review of the recent literature indicated that corticosteroids rather than surgery might be tried at least initially as treatment.

Adult↗

PubMed1998

Advance in the diagnosis of esophageal carcinoma. A new imaging process by adaptive spatial filtering of computed esophagograms.

PURPOSE: To assess the clinical utility of computed radiographic images processed with adaptive spatial filtering (ASF) in the diagnosis of esophageal carcinoma. MATERIAL AND METHODS: After determining the optimal values for ASF image parameters in double-contrast barium studies, we used ASF to process the esophagograms of 35 patients with 37 esophageal carcinomas (superficial 20, advanced 17). The image quality of each lesion was evaluated independently by four radiologists on the basis of detectability, extent, and surface structure. The scoring was: 1 when the ASF image was superior to the original; -1 when the converse was true; and 0 when quality of images was equal. RESULTS: In superficial carcinoma, the mean scores for image quality with regard to detectability, extent, and surface structure were 0.19, 0.48, and 0.31 respectively. In advanced carcinoma, the scores were 0.00, 0.76, and 0.25 respectively. CONCLUSION: ASF offers an improved image quality which is valuable in the evaluation of esophageal carcinoma, particularly in the detection of superficial carcinomas and in the identification of intraepithelial extension.

Barium Sulfate↗

PubMed1998

Early esophageal carcinoma. Evaluation of the depth of invasion based on double-contrast esophagography.

PURPOSE: The aim of this study was to assess the depth of invasion of early esophageal carcinoma (EEC) by means of double-contrast esophagography. MATERIAL AND METHODS: The radiological findings of 46 EECs were retrospectively analyzed for the following factors that might be related to the depth of invasion: in depressed lesions (n = 30): maximum size, surface appearance, sharpness of contour, and wall rigidity; and in elevated lesions (n = 16): maximum size, height, shape, and wall rigidity. All lesions were surgically or endoscopically resected and the radiological findings were compared with the histological appearance. RESULTS: In depressed lesions, the size of the surface granules correlated very strongly with the depth of invasion (rs = 0.8147). In both depressed and elevated lesions, wall rigidity correlated strongly with the depth of invasion (rs = 0.7540 and rs = 0.6702 respectively). In depressed lesions, sharpness of contour also correlated strongly with the depth of invasion (rs = 0.6731). The other factors did not correlate with the depth of invasion. CONCLUSION: Double-contrast esophagography could provide useful information for assessing the depth of invasion of EECs.

Barium Sulfate↗

PubMed1998

Endoscopic treatment of refractory filarial chyluria: a preliminary report.

PURPOSE: We report our experiences treating 5 patients who had filarial chyluria using an endoscopic approach. MATERIALS AND METHODS: Two men and 3 women 47 to 83 years old with chyluria were treated with endoscopic coagulation using guide tube methods. Intrarenal pelvic instillation of silver nitrate was not effective in 4 patients and catheterization was impossible in 1. RESULTS: The responsible lesion was successfully coagulated in all 5 patients. Because the lesion was in the ruptured portion of the caliceal fornix, we thought that chyluria had arisen in the fragile portion of the fornix (fistulization). After endoscopic treatment there was no recurrence in any patient. CONCLUSIONS: Endoscopy is effective and minimally invasive therapy for filarial chyluria.

Aged↗

PubMed1998

Rescue of targeted regions of mammalian chromosomes by in vivo recombination in yeast.

In contrast to other animal cell lines, the chicken pre-B cell lymphoma line, DT40, exhibits a high level of homologous recombination, which can be exploited to generate site-specific alterations in defined target genes or regions. In addition, the ability to generate human/chicken monochromosomal hybrids in the DT40 cell line opens a way for specific targeting of human genes. Here we describe a new strategy for direct isolation of a human chromosomal region that is based on targeting of the chromosome with a vector containing a yeast selectable marker, centromere, and an ARS element. This procedure allows rescue of the targeted region by transfection of total genomic DNA into yeast spheroplasts. Selection for the yeast marker results in isolation of chromosome sequences in the form of large circular yeast artificial chromosomes (YACs) up to 170 kb in size containing the targeted region. These YACs are generated by homologous recombination in yeast between common repeated sequences in the targeted chromosomal fragment. Alternatively, the targeted region can be rescued as a linear YACs when a YAC fragmentation vector is included in the yeast transformation mixture. Because the entire isolation procedure of the chromosomal region, once a target insertion is obtained, can be accomplished in approximately 1 week, the new method greatly expands the utility of the homologous recombinationproficient DT40 chicken cell system.

Animals↗

PubMed1998

Intracellular calcium changes and chemosensitivities of human epidermoid carcinoma cell lines after exposure to cisplatin.

In order to elucidate the mechanisms of cisplatin (cis-diamminedichloroplatinum; CDDP)-resistant tumor cells, we previously established a CDDP-resistant KB cell line (KBrc cells) from a parental KB cell line derived from epidermoid carcinoma (KB cells). The KBrc cells were resistant to 5 kinds of platinum (Pt) drugs. Intracellular Pt concentrations in KBrc cells were lower than in KB cells. Decrease of intracellular Pt concentrations was one of the CDDP-resistant mechanisms. When we measured changes of intracellular calcium ion concentration ([Ca2+]i) during exposure to high-dose CDDP, a sustained elevation of the [Ca2+]i level was observed in the KB cells. These results suggest that the mechanisms underlying CDDP resistance involve changes in calcium channels and an alteration of calcium homeostasis in the tumor cell line.

Antineoplastic Agents↗

PubMed1998

[Orbito-facial reconstruction after extensive anterior skull base, head and neck resection using a rectus abdominis musculocutaneous flap].

In response to the recent advances in aggressive excision of skull base and head and neck malignancies, a more sophisticated method primary reconstruction has been developed using a craniofacial techniques for preservation of postoperative quality of life. We have developed an inferior pedicled rectus abdominis musculocutaneous flap with rib cartilages for reconstruction of the orbito-facial region. The advantages of this flap are as follows; 1) Simultaneous flap elevation in a supine position is possible, 2) Easy, versatile and reliable flap adjustment can be made for complicated space defect, 3) Curvature of the ipsilateral rib cartilages is suitable for inferior orbital rim, 4) Lower risk of pleura laceration as compared with a superior pedicled flap. In the past 5 years, the composite free flaps have been applied for 3 cases of hemi orbito-facial defect, with better results than in previous cases. Our technique for the flap application in a representative case is illustrated.

Head and Neck Neoplasms↗

PubMed1998

[Cyclin protein expression on malignant glioma cells].

Cyclins are key components of the cell cycle progression machinery. Immunohistochemical detection of cyclins in relation to cell position, DNA content, by multiparameter flow cytometry has provided new cell cycle studies. T98G, U373MG, and U251MG were scheduled expression of cyclin A, B1 which are maximal in late S and G2M phase cells. T98G was scheduled expression of cyclin E. being maximal in G1 and S phase cells, but U251MG, U373MG were unscheduled expression of cyclin E. The expression of cyclin D1 were not expressed a pattern. These result may mean that cyclin E in an important protein of cell cycle machinery of malignant brain tumor.

Brain Neoplasms↗