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Biomedical subjects

T Takemura

Publications and source records attributed to T Takemura.

At least 19 recordsLinked to original sources

Alport syndrome and benign familial hematuria (thin basement membrane disease) in two brothers of a family with hematuria.

Alport syndrome (AS) and benign familial hematuria (BFH) are inherited disorders of the glomerular basement membrane, which are sometimes difficult to differentiate at the early stage without type IV collagen staining of the renal basement membrane. Previous studies have indicated that mutation of type IV collagen alpha4 gene may be responsible for both BFH and AS. We report here a Japanese family with consanguinity, in which autosomal-recessive AS and BFH were separately identified in two brothers on the basis of findings of electron microscopy and type IV collagen chain staining of the renal biopsy specimens. Their parents, being first cousins, paternal uncle and grandmothers were found to have hematuria. Our observations suggest that BFH patients were heterozygous carriers of autosomal-recessive AS.

Basement Membrane↗

[Aortic valve replacement with a freestyle stentless valve using the modified subcoronary technique and hemiarch replacement for bicuspid aortic valve and ascending aortic aneurysma; report of a case].

An association between bicuspid aortic valve disease and ascending aortic aneurysma has long been recognized. Root replacement with a composite valve graft for such disease is a well-established technique. But it may involve serious technical difficulties, and may be a more time-consuming procedure than separate valve replacement and graft replacement. We performed an aortic valve replacement with Freestyle stentless valve using the modified subcoronary technique and hemiarch replacement for a 72-year-old man with severe aortic stenosis and ascending aortic aneurysma. Angiographic studies after surgery showed no residual aortic regurgitation (AR) and no deformity of aorta. This technique is an acceptable option for an aortic disease and ascending aneurysma in elderly patients.

Aged↗

[Clinical outcome of emergency off-pump coronary artery bypass grafting].

From January 2001 to January 2003, we performed 25 emergency off-pump coronary artery bypass grafting (CABG) procedures for patients with acute myocardial infarction (AMI) or unstable angina pectoris. During the same period, we also performed 2 emergency on-pump beating CABG procedures for patients with left main coronary trunk (LMT) shock syndrome. For the present study, we evaluated the operative results of the 25 cases of emergency or urgent off-pump CABG. The patients were divided into 3 groups, those with acute AMI with cardiogenic shock (group 1; n = 8), acute myocardial infarction without shock (group 2; n = 8), and unstable angina (group 3; n = 9). There were no differences between groups 1 and 2 with regard to age, number of diseased vessels, and preoperative use of an intraaortic balloon pump, however, patients in group 1 had a higher number of completely obstructed coronary arteries. Patients in groups 1 and 2 underwent off-pump CABG within 3.5 hours after a coronary angiography or coronary intervention procedure, while those in group 3 underwent off-pump CABG within 2 days of coronary angiography. The mean number of grafts per patient was 1.8, 2.1, and 2.3 in groups 1, 2, and 3, respectively. One group 1 patient with an LMT lesion was transferred to on-pump beating CABG because of hemodynamic instability. The 30-day mortality rate was 38% (3 of 8) in group 1, whereas it was 0% in groups 2 and 3. Intubation time, ICU stay, and postoperative stay were similar among the 3 groups. An early angiographic study was undertaken in all surviving patients and the results demonstrated patency in all of the examined grafts. Although our results are limited, emergency off-pump CABG was found to be safe and feasible for AMI without cardiogenic shock or unstable myocardial ischemia. However, the outcome of this procedure for patients with preoperative cardiogenic shock was not satisfactory, therefore, a combination therapy of appropriate mechanical circulatory support, prior revascularization by catheter intervention, and emergency surgical revascularization are considered to improve survival of those patients.

Aged↗

[Economic evaluation of off-pump coronary artery bypass grafting; compared to conventional coronary artery bypass grafting].

This study was undertaken to compare economic outcomes of off-pump coronary artery bypass grafting (off-pump CABG: OPCAB) and conventional CABG (CCABG). We reviewed the medical records of 5 patients with ischemic coronary disease (IHD) who underwent OPCAB and 5 patients with IHD who underwent CCABG. A hospital income which was based on a current Japanese health insurance system was indicated. There were significant differences in total cost (OPCAB = 208,200 +/- 7,383 yen versus CCABG = 324,300 +/- 10,290 yen, 35.8% decreased), costs of medical materials and transfusions (OPCAB = 14,760 +/- 3,270 yen versus CCABG = 87,540 +/- 3,326, 81.3% decreased) and charges of surgery and anesthesia (OPCAB = 130,400 +/- 1,853 yen versus CCABG = 147,650 +/- 4,167 yen, 12% decreased) OPCAB markedly reduces the cost of hospitalization. But charges of surgery and anesthesia of OPCAB seems to be valued properly in a current Japanese health insurance system.

Anesthesia↗

[Usefulness of silicone blake drains after cardiac surgery].

In the present study, the drainage system consisting of a silicon blake drain and a portable suction reservoir (J-vac system) was applied to the patients who received cardiac surgery (SD group). Postoperative drainage volume, postoperative pericardial effusion volume, and postoperative length of hospital stay in SD group were compared with those in the patients who received cardiac surgery and were applied a conventional chloroethlene drain (CD group). There were no significant differences in postoperative drainage volume, postoperative pericardial effusion volume, or postoperative length of hospital stay between SD and CD groups. Therefore, its was thought that a silicon back drain could be safely used as a drainage system after heart surgery. Recently the development of less-invasive cardiac surgery made the early hospital discharge possible, and J-vac system might be very useful in view of its portability under such clinical settings.

Adult↗

[Apico-aortic conduit for severe aortic stenosis in elderly].

We described a case of an 84-year-old woman with end stage aortic stenosis in whom favorable results were obtained after constructing apico-aortic conduit bypass. The patient admitted due to complete atrio ventricular(AV) block and respiratory insufficiency. Although a permanent pacemaker was implanted, heart failure did not improve. Echocardiograms showed small aortic annulus and severe calcific aortic stenosis with a measured trans valve gradient of 100 mmHg. Since cardiac failure deteriorated and she lapsed into hypotension and acute renal failure, an emergency operation was performed. The left lateral thoracotomy was performed with cardiopulmonary bypass. A bioprosthetic valved conduit was anastmosed to the left ventricle apex. Another graft was anastomosed to the discending thoracic aorta. The operation was completed by anastomosing the tailored ends of the grafts together. Although the patient required hemodialysis for 2 weeks after operation, she was discharged on 57th day after operation without any complications. Apico-aortic conduit is considered to be an useful procedure for elderly patients who were not good candidates for conventional valve replacement.

Aged↗

Malignant epithelial tumor of unknown origin of the broad ligament.

Malignant epithelial tumor of the broad ligament is rare and to our knowledge only 17 cases have been reported. We report a 54-year-old Japanese woman in whom transvaginal sonography (TVS) and magnetic resonance imaging (MRI) showed a left adnexal tumor. Serum CA125 was elevated to 10,000 U/ml. Preoperatively, we diagnosed this tumor was a left ovarian malignant tumor though, it was confirmed a the 47x57 mm tumor in the left broad ligament at laparotomy. Histologically most of the tumor showed serous papillary adenocarcinoma with changes similar to poorly differentiated carcinoma and as seen in transitional cell carcinoma on hematoxylin-eosin staining. After three courses of platinum based adjuvant chemotherapy, the patient is alive with no recurrence at 18 months postoperatively.

Broad Ligament↗

Infection of macaques with chimeric simian and human immunodeficiency viruses containing Env from subtype F.

Chimeric simian and human immunodeficiency viruses (SHIVs) are useful for investigating the pathogenicity of human immunodeficiency virus (HIV-1) and to develop an anti-HIV-1 vaccine. We attempted to construct SHIVs containing Env from various subtypes, because almost all SHIVs which have been reported so far have Env from HIV-1 that belongs to subtype B. Two infectious SHIVs containing Env from two strains of HIV-1, CMR304 and CMR306, which belong to subtype F and A, respectively, were newly obtained. These SHIVs essentially showed a coreceptor usage and a neutralization pattern that were similar to those of the parental HIV-1s. In macaque PBMC, SHIVcmr304 replicated with kinetics similar to that of prototypic SHIV-NM-3rN with HIV-1 NL432 Env, but SHIVcmr306 replicated poorly. Inoculation of four rhesus macaques with SHIVcmr304 resulted in an increase of plasma viral load in all the macaques, though viral RNA copies were 100-fold lower than that in the infection with NM-3rN. This SHIV containing Env from HIV-1 subtype F will be a valuable source for the analysis of HIV-1 subtype F and the evaluation of vaccine candidates as a genetically divergent challenge virus.

Animals↗

[Graft holding system; a new device for coronary artery bypass grafting].

A new graft holding system for coronary artery bypass grafting was described. This system was an application of a memo-clip, which was composed of a flexible arm and 2 paper clips at both ends. A graft was wrapped by a piece of sponge and pinched indirectly by one of the clips. The other clip was fixed at an edge of the sternal retractor. Regardless of the size of the graft or the amount of the surrounding tissue, the graft can be fixed securely at one's pleased position due to a flexible arm of the device. Intimal injury can be avoided referring to the gentle holding of a piece of sponge. It enables us to place precise stitches and to minimize handling, anastomosis time, and leakage.

Anastomosis, Surgical↗

Characterization of less pathogenic infectious molecular clones derived from acute-pathogenic SHIV-89.6p stock virus.

For a better understanding of the acute pathogenicity of SHIV-89.6P stock virus, which induces prominent CD4 cell loss within a month after inoculation in monkeys, we have constructed four infectious molecular clones (cl 18, cl 64, cl 69, and cl 71). Cl 64, cl 69, and cl 71, like the parental virus, showed a high in vitro replication ability and a pathogenic-like effect (CD4 downmodulation) in a monkey CD4(+) cell line, whereas cl 18 showed a lower replication ability and could not downmodulate CD4. Cl 64, which has characteristics similar to those of the parental virus in vitro, was inoculated into four rhesus monkeys. All monkeys showed a plasma viral load similar to that of the parental virus with a peak at 2 weeks after inoculation. However, the viral load gradually decreased and the virus failed to cause an AIDS-like disease in infected monkeys, but it induced a strong antiviral antibody response. These results demonstrate the polyclonal nature of the parental SHIV-89.6P virus stock and demonstrate that cl 64, aside from its high replicability, may differ qualitatively from the parental virus.

Acquired Immunodeficiency Syndrome↗

Phase I/II study of intravenous nedaplatin and intraarterial cisplatin with transcatheter arterial embolization for patients with locally advanced uterine cervical carcinoma.

BACKGROUND: Nedaplatin, a platinum analog with less renal toxicity and similar efficacy for cervical carcinoma, recently has been shown to have a synergistic effect on cervical carcinoma lines in combination with cisplatin. To determine the clinical efficacy of this combination in patients with cervical carcinoma, the authors conducted a Phase I/II study of intravenous nedaplatin and intraarterial cisplatin combined with transcatheter arterial embolization (TAE). METHODS: Eligibility criteria were as follows: cervical carcinoma (Stages IB2-IV; International Federation of Gynecology and Obstetrics), 16-70 years of age, performance status between 0 and 2, and adequate bone marrow, renal, and hepatic function. Nedaplatin (40-70 mg/m2) was administered intravenously on Day 1 followed by intraarterial administration of cisplatin (70 mg/m2) on Day 3 via both uterine arteries by using the Seldinger method. This then was followed by TAE. This course of treatment was repeated every 3 weeks for 3 cycles. RESULTS: Patient data were as follows: age 37-68 (median, 55 years) and Stages IB2:4, IIA:3, IIB:2, IIIA:1, IIIB:3, IVA:2 carcinoma. The response to therapy was defined by magnetic resonance imaging as follows: partial response in 60% (9 of 15) of patients, complete response in 40% (6 of 15) of patients, and an overall response rate of 100% (95% confidence interval, 78-100%). Myelosuppression was manageable. Grade 3/4 renal toxicity was observed in 2 patients who received 70 mg/m2 of nedaplatin. Thirteen patients received radical hysterectomy, 1 patient received lymph node sampling, and 11 patients received adjuvant radiotherapy or chemotherapy. CONCLUSIONS: The maximum tolerable dose was 70 mg/m2 nedaplatin, and the dose-limiting toxicity was renal toxicity. The recommended dose was 60 mg/m2 nedaplatin intravenously followed by 70 mg/m2 cisplatin intraarterially. Intravenous nedaplatin followed by intraarterial cisplatin with TAE appears to be very effective for locally advanced cervical carcinoma.

Adult↗

Frequent loss of imprinting of IGF2 and MEST in lung adenocarcinoma.

Genomic imprinting is a parental origin-specific chromosomal modification that causes differential expression of maternal and paternal alleles of a gene. Accumulating evidence suggests that deregulation of imprinted genes, including loss of imprinting (LOI), plays a role in oncogenesis. In the present study, we investigated allelic expression of six imprinted genes in human lung adenocarcinomas as well as in matched normal lung tissue. Informative cases showing heterozygosity for the gene of interest were selected from 35 patients. LOI of the insulin-like growth factor 2 gene (IGF2) and mesoderm-specific transcript (MEST, also known as paternally expressed gene 1) was noted in 47% (seven of 15) and 85% (11 of 13) of informative cases, respectively. Monoallelic expression was maintained in all the matched normal tissues examined. LOI of IGF2 was seen more frequently in moderately to poorly differentiated adenocarcinomas. In contrast, H19, small nuclear ribonucleoprotein-associated polypeptide N gene (SNRPN), necdin gene (NDN), and long QT intronic transcript 1 (LIT1) exhibited consistent monoallelic expression in all the informative samples. These findings indicated that independent deregulation took place in imprinted genes and suggested that aberrant imprinting of IGF2 and MEST was involved in the development of lung adenocarcinoma.

Adenocarcinoma↗

Ossification of tracheal cartilage in aged humans: a histological and immunohistochemical analysis.

Tracheal cartilage has been considered as permanent cartilage without endochondral ossification. We examined ossification of the tracheal cartilage in 25 adults (mean age 67.8 years; range 20-87 years; male:female = 17:8). Thirteen cases (52%) demonstrated ossification of the tracheal cartilage, accompanied by the formation of lamellar bones with fatty bone marrow. Ossification was observed at the lateral peripheral region of the tracheal cartilage, while vascular invasion into the cartilage was seen even where no ossification was present. Twenty-two cases (88%) showed marked hyalinization in the central region of the tracheal cartilage. Type II collagen was immunolocalized in the cartilage matrix, except for in the central hyalinized area, while type I collagen was immunolocalized around the perichondrium and ossified areas in the tracheal cartilage. Type X collagen immunolocalized on territorial matrices around the lacunae near the ossified regions. These results suggest that tracheal cartilage in aged humans frequently ossifies physiologically, and that aging promotes osteogenesis, even in permanent cartilage.

Adult↗

Cartilage-specific matrix protein chondromodulin-I is associated with chondroid formation in salivary pleomorphic adenomas: immunohistochemical analysis.

Chondromodulin-I (ChM-I) is a novel cartilage-specific matrix protein. In the growth plates of the long bones, ChM-I was shown to be expressed in mature to upper hypertrophic chondrocytes, and to be deposited in the cartilage matrix. As ChM-I strongly inhibits angiogenesis, cartilage is avascular. Also, ChM-I has bifunctional activity against chondrocyte proliferation. On the other hand, pleomorphic adenomas of the salivary glands frequently have chondroid elements. To elucidate the relationship between chondroid formation and hypovascularity in salivary pleomorphic adenomas, we immunohistochemically examined the expression and localization of ChM-I in 35 cases of this tumor. ChM-I was immunolocalized to the lacunae in the chondroid elements of pleomorphic adenomas (100%). Type II collagen and aggrecan were immunolocalized throughout the matrix around lacuna cells of the chondroid element (100%, 91.7%), and ChM-I was infrequently immunolocalized to the spindle-shaped myoepithelial cells in the myxoid element (37.5%). Fibroblast growth factor-2 was strongly immunolocalized to the lacuna cells in the chondroid element (100%), among the neoplastic myoepithelial cells in the myxoid elements (96.9%), and on the basement membranes around the solid nests of neoplastic myoepithelial cells (71.4%). Although CD34 is a marker of endothelial cells, CD34 was expressed in the endothelial cells in only a few areas around the epithelial elements and in the fibrous element of pleomorphic adenomas. No signals for CD34 were observed in chondroid elements in pleomorphic adenomas (P < 0.001), but a few signals were seen in the myxoid elements (P < 0.05). These findings suggested that lacuna cells and neoplastic myoepithelial cells expressed ChM-I, and that this molecule may play an important role in hypovascularity and chondroid differentiation in pleomorphic adenoma. In conclusion, pleomorphic adenoma expressed ChM-I, which is involved in hypovascularity and chondroid formation in this type of tumor.

Adenoma, Pleomorphic↗

Identification of two novel mutations in the CLCN5 gene in Japanese patients with familial idiopathic low molecular weight proteinuria (Japanese Dent's disease).

Two Japanese patients, belonging to unrelated families, with idiopathic low-molecular-weight proteinuria (LMWP; Japanese Dent's disease) showed novel mutations of the gene encoding renal-specific chloride channel 5 (CLC-5). Proteinuria was first noticed at the ages of 2 and 3 years in patients 1 and 2, respectively. During follow-up, marked increases in urinary ss(2)-microglobulin levels, hypercalciuria, and high levels of urinary excretion of growth hormone were observed in both patients. Nephrocalcinosis was detected in patient 2. Renal biopsy specimens from both patients showed minimal alterations in glomeruli and tubulointerstitium, except for mild mesangial proliferation in patient 2. DNA sequence analysis of the entire 2,238-bp coding region and exon-intron boundaries of the CLCN5 gene showed the presence of two novel mutations in exon 10, consisting of one missense mutation (I524K) in patient 1 and one nonsense mutation (R637X) in patient 2. DNA analysis and measurement of urinary ss(2)-microglobulin levels in family members indicated an X-linked mode of inheritance in patient 1 and sporadic occurrence in patient 2. These results have expanded our understanding of the association between idiopathic LMWP (Japanese Dent's disease) and mutations of the CLCN5 gene.

Adolescent↗

Immunohistochemical localization of members of the transforming growth factor (TGF)-beta superfamily in normal human salivary glands and pleomorphic adenomas.

Although pleomorphic adenoma is the most common type of salivary gland epithelial tumor, it frequently contains "mesenchymal"-like components, including myxoid or chondroid tissues. We reported previously that chondroid tissue formation in pleomorphic adenoma was associated with overexpression of bone morphogenetic proteins (BMPs) by neoplastic myoepithelial cells. BMPs belong to the transforming growth factor (TGF)-beta superfamily, so we hypothesized that pleomorphic adenoma may express TGF-betas and that these molecules may regulate mesenchymal-like tissue formation. To evaluate this hypothesis, we immunohistochemically examined TGF-beta1, -beta2 and -beta3 expression and localization in normal salivary glands and in 43 cases of pleomorphic adenomas. There was no evidence of TGF-beta1 expression in normal salivary glands or pleomorphic adenomas. Signals for TGF-beta2 in the normal salivary glands were observed in the intercalated ducts, while in pleomorphic adenomas they were observed in the inner ductal cells of the tubulo-glandular structures. Signals for TGF-beta3 in the normal salivary glands were observed in mucous cells, whereas in pleomorphic adenomas they were observed in the solid nests of neoplastic myoepithelial cells, in the portion showing squamous metaplasia, and in the inner ductal cells of tubulo-glandular structures. TGF-betas induce ectopic cartilage formation in vivo, but chondroid tissues in pleomorphic adenomas showed only weak TGF-beta3 expression. TGF-beta may be related to differentiation of the inner ductal cells and the neoplastic myoepithelial cells. In conclusion, pleomorphic adenomas expressed TGF-beta2 and -beta3, which may be associated with differentiation of the inner ductal cells and neoplastic myoepithelial cells.

Adenoma, Pleomorphic↗

Angiogenesis and phenotypic alteration of alveolar capillary endothelium in areas of neoplastic cell spread in primary lung adenocarcinoma.

Normal alveolar capillary endothelium is quiescent in nature and displays anticoagulant thrombomodulin (TM) on its surface. The cytoplasms of these endothelial cells are ultrastructurally non-fenestrated type, and they barely express von Willebrand factor (vWf). Alveolar fibrosis is accompanied by a capillary endothelium reactive for vWf, and a loss of TM expression. In primary lung adenocarcinoma, neovascularization occurs in association with alveolar fibrosis. In order to study basic factors related to angiogenesis and phenotypic changes of the capillaries located in tumor-bearing alveolar walls, we examined 37 primary lung adenocarcinomas with electron microscopy and confocal laser scanning microscopy with antibodies for TM, vWf, vascular endothelial growth factor (VEGF), and its receptors (KDR and Flt-1), and proliferating markers (Ki-67/proliferating cell nuclear antigen). Tissues microdissected specifically from alveolar walls were used for reverse transcription-polymerase chain reaction (RT-PCR) to assess expressions of mRNA isoforms of VEGF and its receptors. New capillary branching was found by ultrastructural study in the alveolar walls in 12% of the patients. Nuclei of the capillary endothelial cells were reactive for proliferating cell markers. Endothelial fenestrae were developed in 65% of the patients, TM reactivity was lost in the alveolar capillaries, and their cell cytoplasms obtained a reactivity for vWf through a transitional mosaic-like distribution pattern of both antigens. Besides cytoplasmic VEGF expression in neoplastic cells, tumor-bearing alveolar walls showed significant expression of mRNA of VEGF165 and KDR. These findings imply that angiogenesis and phenotypic changes of the alveolar capillaries are closely related to a higher expression of tumor-associated VEGF165 and of KDR in the alveolar walls in primary lung adenocarcinoma.

Adenocarcinoma↗

Aerogenous spread of primary lung adenocarcinoma induces ultrastructural remodeling of the alveolar capillary endothelium.

To determine whether pulmonary alveolar capillaries manifest ultrastructural remodeling at areas of neoplastic invasion of primary lung adenocarcinomas, we examined 17 well-differentiated adenocarcinomas of lung (2 bronchioloalveolar and 15 papillary adenocarcinomas) by electron microscopy. The expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) was demonstrated by immunohistochemical stainings. VEGF messenger RNA (mRNA) isoforms were detected by reverse-transcription polymerase chain reaction (RT-PCR) in alveolar walls microdissected from normal and tumor-associated tissues. Cytoplasm of neoplastic cells expressed VEGF protein in all patients. Endothelial cell nuclei of alveolar capillaries showed positive reaction for PCNA. Alveolar capillary lumina were distended like venules, and some intercellular junctions remained open. The cytoplasm of the capillary endothelial cells was enlarged and developed numerous organelles such as Weibel-Palade bodies and vesiculovacuolar organelles, in contrast to marked attenuation in their normal counterpart. Capillary sprouting occurred from proper alveolar capillaries in 2 patients. Cytoplasmic segments became extremely attenuated and developed diaphragm-like fenestrae in 65% of the patients. A relatively higher expression of diffusable isoforms of VEGF mRNA was seen in the tumor-bearing alveolar walls than in normal walls. Expression of KDR (one of the VEGF receptors) mRNA in tumor exceeded that in normal tissues. These results suggest that diffusable isoforms of VEGF mRNA released from the neoplastic cells are deeply involved in the induction of growth activity of alveolar capillary endothelial cells as much as in the characterization of tumor-associated microvessels in primary lung adenocarcinomas.

Adenocarcinoma, Bronchiolo-Alveolar↗