Biomedical subjects

K Ito

Publications and source records attributed to K Ito.

At least 217 records · Page 12Linked to original sources

PubMed2001

Pedicle myocutaneous flaps for reconstruction following total pelvic exenteration of intrapelvic recurrent rectal cancer: report of a case.

A vast metastatic tumor mass of recurrent rectal carcinoma in the intrapelvic organs is commonly considered unsuitable for total pelvic exenteration (TPE); first, because it is unlikely that it would improve the prognosis and health-related quality of life of the patient, and second, because of the difficulties involved in this surgical technique. However, by using a plastic surgery technique involving reconstruction by filling the pelvic dead space with pedicle myocutaneous flaps (PMF), primary wound closure and extensive resection of the perineum can be achieved, whereby postoperative metastasis may be prevented. We report herein the case of a 71-year-old man found to have local recurrence in the perineum with extensive invasion of the soft tissue as well as adjacent organs, 20 months after abdominal perineal resection for rectal carcinoma. TPE with extensive resection of the perineal soft tissue was performed, followed by perineal reconstruction and packing of the pelvic dead space with PMF, mainly constructed from the gracilis and sartorius muscles of both femurs. His postoperative course was uneventful and he has remained free of local recurrence and symptomatic perineal complaints for 1 year. In this report, we examine the effectiveness of using the gracilis muscle for PMF in intrapelvic and perineal reconstruction after TPE.

Adenocarcinoma↗

PubMed2001

Small incisional esophagectomy with endoscopic assistance: evaluation of a new technique.

Laparoscopic surgery now can be performed safely and efficiently for various types of cancer; however, reconstruction of the gastric tube may be technically demanding. We attempted to make a breakthrough by designing and employing a new technique for performing a small incisional operation with endoscopic assistance. A midline incision, 10cm in length, was made in the upper abdomen. Some procedures were performed through the incision under direct vision, while other procedures required in the lateral extremes of the abdominal cavity, that are inaccessible by direct vision, were performed by laparoscopic-assisted surgery. Similarly, intrathoracic procedures were essentially performed through a minithoracotomy, 10-15cm in length, made without dissection of the dorsal latissmus or anterior serratus muscles. The postoperative courses of 20 consecutive patients who underwent this procedure were generally uneventful, and significant improvements in terms of intensive care and analgesic requirements were observed.

Aged↗

PubMed2001

Effect of low doses of L-NAME on methamphetamine-induced dopaminergic depletion in the rat striatum.

The toxic dose of methamphetamine (METH) (5 mg/kg, s.c., x4, 2 hr intervals) decreased contents of dopamine, dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in striatum, and decreased contents of serotonin (5-HT) in both striatum and nucleus accumbens. Administration of low doses of a non-selective endothelial and neuronal nitric oxide synthase (NOS) inhibitor, N omega-nitro-L-arginine methyl ester (L-NAME) (5 and 10 mg/kg, i.p., x1) intensified the METH-induced decreases in contents of dopamine and its metabolites in striatum. NO substrate, L-arginine (500 mg/kg, i.p., x4) reversed these effects of L-NAME on the METH-neurotoxicity. L-NAME did not change the METH-induced hyperthermia. These findings, which are contrary to our previous study with a high dose of L-NAME, suggest that the inhibition of endothelial or neuronal NOS-mediated NO production by low doses of L-NAME enhanced the METH-induced neurotoxicity. The finding that L-NAME can have opposite effects on the METH-neurotoxicity according to the dosing is important, however, additional experiments should be performed to clarify which type of NOS is related to these effects.

3,4-Dihydroxyphenylacetic Acid↗

PubMed2001

Identification of human multidrug resistance protein 1 (MRP1) mutations and characterization of a G671V substitution.

The multidrug resistance protein 1 (MRP1) belonging to the ATP-binding cassette (ABC) superfamily of transport proteins can confer resistance to multiple natural product drugs and methotrexate in human tumor cells. In addition, MRP1 is expressed in normal tissues acting as an efflux pump for glutathione, glucuronate, and sulfate conjugates and may thus influence the pharmacokinetic properties of many drugs. Using polymerase chain reaction-single-strand conformation polymorphism analysis, we screened 36 Caucasian volunteers for mutations in the coding exons of the MRP1 gene, including the adjacent intron sequences. Among several mutations found, two are expected to cause amino acid substitutions. One of these mutations (G671V) was of special interest because it is located near the first nucleotide binding domain. To determine whether this mutation caused a change in the MRP1 phenotype, a mutant MRP1 expression vector was constructed and transfected into SV40-transformed human embryonic kidney cells (HEKSV293T) and the transport properties of the mutant protein were examined. Transport of the MRP1 substrates leukotriene C4, 17beta-estradiol 17beta-(D)-glucuronide, and estrone sulfate by membrane vesicles prepared from transiently transfected HEKSV293T cells was comparable to that of wild-type MRP1.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2001

Gastrectomy for a patient with early gastric cancer and human immunodeficiency virus (HIV) infection.

Gastric cancer associated with human immunodeficiency virus (HIV) infection is rare, and mostly results in a poor outcome. We report a patient with HIV infection and early gastric cancer successfully treated by gastrectomy. A 49-year-old man with a 6-year history of HIV infection underwent gastric fiberscopy, and a IIc-type depressed lesion was detected in the gastric antrum. With a diagnosis of early gastric cancer, we abided strictly by standard precautions for patients with HIV infection and carried out Billroth I gastrectomy. Histologic examination revealed that the lesion (which measured 0.9 x 0.4 cm in size), was well differentiated tubular adenocarcinoma confined to the mucosa. A review of the literature disclosed that this is the first reported case of early gastric cancer associated with HIV infection.

Adenocarcinoma↗

PubMed2001

The effect of food consistency and dehydration on reflex parotid and submandibular salivary secretion in conscious rats.

Changes in salivary secretion with different consistency of diet and dehydration were studied in male Wistar rats under unrestricted conditions. To measure the salivary secretion, a stop-flow method was used. There was little unstimulated salivary secretion from the parotid and submandibular glands, but eating solid, powdered, and liquid diets induced parotid and submandibular saliva. There was no significant change in the volume and flow rate of saliva in bilateral parotid glands during the eating of solid diets. The solid and powdered diets induced significantly more salivary secretion from the parotid gland than did the liquid. The salivary flow rate with solid diets was significantly greater from the parotid gland than from the submandibular. On the other hand, the salivary flow rate with the liquid diet was significantly smaller from the parotid gland than from the submandibular. Appreciable amounts of submandibular saliva, but little parotid saliva were secreted during grooming. Clearly, parotid and submandibular saliva have different roles in the rat. When injected intraperitoneally with 1.5 M NaCl solution or water-deprived for 24 h, rats took longer to eat the solid diets, and had increased salivary volume and decreased flow rate from the parotid gland. These results indicate that the moisture content of the diet and the dryness of the mouth alters the volume of parotid saliva secreted in rats and show that parotid saliva plays an important part in mastication and swallowing.

Animals↗

PubMed2001

The distribution and production of cholesteryl ester transfer protein in the human aortic wall.

Cholesteryl ester transfer protein (CETP) has been considered to mediate the transfer of cholesteryl ester from arterial wall, however, the distribution and production of CETP in human arterial wall remains unclear. Present study histopathologically demonstrated the distribution of CETP and CETP mRNA in the human aortic wall by immunohistochemistry and in situ hybridization. While CETP was constantly distributed in the media, the protein was recognized within the intima with fibrocellular thickening and atherosclerotic intima. Double immunostaining methods demonstrated CETP expression in smooth muscle cells in the intima and media. CETP mRNA was detected not only in intimal cells but medial smooth muscle cells. Intimal cells expressing CETP mRNA were considered to be monocyte-derived macrophages and smooth muscle cells by immunohistochemistries using two antibodies against smooth muscle actin and human macrophage on the subserial sections. Our in vivo study provides that CETP is produced by smooth muscle cells in the intima and media of human aorta, and it is suggested that arterial smooth muscle cells positively participate in the removal of excessive cholesteryl ester from the arterial wall by CETP production.

Aorta↗

PubMed2001

Neural substrates for recognition of familiar voices: a PET study.

Identification of familiar people is essential in our social life. We can identify familiar people by hearing their voices as well as by viewing their faces. By measuring regional cerebral blood flow (rCBF) by positron emission tomography (PET), we identified neural substrates for the recognition of familiar voices. The brain activity during discrimination of voices of the subjects' associates and friends from those of unfamiliar people was compared with that during an analogous discrimination of their own voice from unfamiliar voices as well as during vowel discrimination. The left frontal pole, right temporal pole, right entorhinal cortex, and left precuneus were activated to a greater extent during discrimination of familiar voice than during control discriminations, suggesting that these brain regions are involved in the recognition of familiar voices. Furthermore, the adjusted values of rCBF in the left frontal pole and right temporal pole correlated with the number of subjects' correct identification of familiar voices. The present results suggest that these two regions are coactively associated with matching the currently heard voice to familiar voices in one's memory.

Adult↗

PubMed2001

Diagnostic significance of digital rectal examination and transrectal ultrasonography in men with prostate-specific antigen levels of 4 NG/ML or less.

OBJECTIVES: To investigate the usefulness of digital rectal examination (DRE) and transrectal ultrasonography (TRUS) for prostate cancer diagnosis and to propose a diagnostic algorithm for individual-based cancer screening in subjects with prostate-specific antigen (PSA) levels of 4.0 ng/mL or less. METHODS: Between January 1992 and March 2000, 129 subjects with PSA levels of 4.0 or less and abnormal findings on DRE or TRUS underwent prostate biopsy. The subjects were divided into four groups according to the PSA range: 0 to 0.9 ng/mL, 1.0 to 1.9 ng/mL, 2.0 to 2.9 ng/mL, and 3.0 to 4.0 ng/mL. The reliability of the DRE and TRUS and the clinicopathologic features of prostate cancer were investigated among these four groups. RESULTS: Of the 129 subjects, 17 (13.2%) patients with prostate cancer were diagnosed. The detection rate was 2.2% (1 of 45), 0% (0 of 27), 20.6% (7 of 34), and 39.1% (9 of 23) in subjects with PSA levels of less than 1.0 ng/mL, 1.0 to 1.9 ng/mL, 2.0 to 2.9 ng/mL, and 3.0 to 4.0 ng/mL, respectively. The proportion of patients with Stage II, III, and IV was 58.8%, 41.2%, and 0%, respectively. The percentage with Gleason scores of 8 to 10 was 17.6%. The detection rate of abnormal findings on DRE and TRUS was 14.4% (13 of 90) and 9.5% (7 of 74), respectively. Adding TRUS to DRE in the screening program of subjects with PSA levels of 2.0 to 4.0 ng/mL, increased the detection rate of prostate cancer to 30.8% (4 of 13). CONCLUSIONS: Routine prostate biopsy should not be undertaken except for highly suspicious DRE findings in subjects with PSA levels less than 2.0 ng/mL. The additional use of TRUS in subjects with PSA levels of 2.0 to 4.0 ng/mL would improve the sensitivity of prostate cancer detection. The diagnostic algorithm proposed in the present study is useful as a screening method for prostate cancer in subjects with PSA levels of 4.0 ng/mL or less.

Adult↗

PubMed2001

Plant regeneration from cell suspension-derived protoplasts of Primula malacoides and Primula obconica.

Protoplasts were isolated from cell suspension cultures of Primula malacoides cv. 'Lovely Tokyo' and P. obconica cv. 'Aalsmeer Giant White'. P. obconica protoplasts were embedded in 0.1% (w/v) gellan gum-solidified discs comprising MS medium supplemented with 3 mg/l of 2,4-D or picloram, 0.1 mg/l of zeatin, 0.2 M glucose and 0.2 M mannitol, and surrounded by a liquid medium of the same composition except for the addition of 0.1% (w/v) activated charcoal. The protoplasts formed visible colonies, which were transferred to the regeneration medium containing 30 g/l of sucrose, 0.1 mg/l of picloram and 2 mg/l of zeatin for shoot induction. P. malacoides protoplasts formed visible colonies when cultured in disc culture using 0.1% (w/v) gellan gum-solidified MS medium containing 5 mg/l of 2,4-D, 1 mg/l of NAA, 0.1 mg/l of zeatin and 0.4 M glucose. Small calli were transferred to MS medium supplemented with 5 mg/l of zeatin for shoot regeneration. The shoots of both species readily rooted on plant growth regulator-free 1/2 MS medium and successfully acclimatized to greenhouse conditions. The protoplast-derived plants showed some alterations in morphological characteristics from those of the in-vitro-germinated control plants.

Journal Article↗

PubMed2001

MR imaging of pancreatic diseases.

This article presents current MR imaging techniques for the pancreas, and review a spectrum of MR imaging features of various pancreatic diseases. These include: 1) congenital anomalies such as anomalous union of pancreatobiliary ducts, divisum, and annular pancreas, 2) inflammatory diseases, including acute or chronic pancreatitis with complications, groove pancreatitis, and autoimmune pancreatitis, tumor-forming pancreatitis, 3) pancreatic neoplasms, including adenocarcinoma, islet cell tumors, and cystic neoplasms (microcystic adenoma, mucinous cystic neoplasms, and intraductal mucin-producing pancreatic tumor). Particular attention is paid to technical advances in MR imaging of the pancreas such as fat-suppression, MR pancreatography (single- or multi-slice HASTE), and thin-section 3D multiphasic contrast-enhanced dynamic sequences. Imaging characteristics that may lead to a specific diagnosis or narrow the differential diagnosis are also discussed.

Acute Disease↗

PubMed2001

The material properties of the bovine acetabular labrum.

The compressive and tensile material properties of the bovine acetabular labrum were measured. Confined compression testing was used to determine the aggregate compressive modulus and the permeability of the labrum. The compressive modulus of the labrum (0.157 +/- 0.057 MPa) is comparable to that of the morphologically similar meniscus, and approximately one-quarter to one-half that of the adjoining acetabular cartilage. The permeability of the labrum (4.98 +/- 3.43 x 10(-16) m4/N s) was lower than that of the meniscus and cartilage. With a significantly higher resistance to interstitial fluid flow across the acetabular rim than along the rim. Specimens from the posterior and superior regions of the labrum were tested to failure in uniaxial tension. The maximum stress at failure (11.9 +/- 6.1 MPa), maximum strain at failure (26.5 +/- 7.6%) and tangent modulus (74.7 +/- 44.3 MPa) were similar to those reported for the bovine meniscus, and to other tissues composed of highly oriented collagen fiber bundles. In tension, the labrum is much stiffer (10-15 x) than the adjoining articular cartilage, and the posterior region of the labrum is significantly stiffer (45%) than the superior region. The labrum's low permeability may contribute to sealing of the hip joint. The high circumferential tensile stiffness of the labrum, together with its ring structure, reinforce the acetabular rim and may contribute to joint stability.

Acetabulum↗

PubMed2001

Direction-dependent resistance to flow in the endplate of the intervertebral disc: an ex vivo study.

A comparison of the higher hydrostatic pressure in the nucleus of the healthy intervertebral disc during daily loading with the relatively lower osmotic swelling pressure in the disc during rest suggests the existence of direction-dependent flow resistance such that all of the fluid exuded from the disc during loading is recovered during rest. In this study, this direction-dependent resistance was demonstrated for flows through the cartilage endplates and the underlying marrow contact channels in the bony endplates. Using an ex vivo sheep endplate model, the resistance ratio (Rout/Rin) for flow through the endplate was 39.0+/-3.8 (mean +/- S.E.). In addition, a path of fluid flow through the marrow contact holes was revealed using fluorescent staining.

Animals↗

PubMed2001

Biological characteristics and chemosensitivity profile of four human anaplastic thyroid carcinoma cell lines.

Anaplastic thyroid carcinoma is a rapidly growing, aggressive neoplasm affecting the elderly which does not respond to most of the therapies. We established cultured cell lines from four untreated tumors. The cultures grew in a monolayer of spindle-shaped cells in three cell lines and of small polygonal cells in one line, having relatively long doubling times and chromosomal abnormalities. The xenotransplantation of the lines in athymic nude mice produced tumors with a histology similar to the original tumors. The immunocytochemical staining showed the expression of PCNA, HLA-class 1, cytokeratin, vimentin and FAS (fatty acid synthase) but not CEA, desmin or P-glycoprotein. The lines secreted TPA, IL-6, IL-8 and few or no thyroid-related hormones in the culture supernatant. One cell line produced G-CSF. The chemosensitivity assay revealed intrinsic drug resistance to nine out of 11 antineoplastic agents. The reverse transcriptase-polymerase chain reaction (RT-PCR) detected MRP (multidrug resistance-associated protein) mRNA but not mdr (multidrug resistance protein)-1 and mdr-3 mRNAs. This finding indicates that the multidrug resistance of these lines is mediated by a P-glycoprotein-unrelated mechanism. The RT-PCR also presented FAS mRNA in all the lines, and IL-6 and IL-8 mRNAs in some of the lines.

ATP Binding Cassette Transporter, Subfamily B↗

PubMed2001

Cloning and expression pattern of a novel PEBP2 beta-binding protein (charged amino acid rich leucine zipper-1[Crl-1]) in the mouse.

PEBP2 beta/Cbf beta is the beta subunit of PEBP2/Cbf, which has been demonstrated to have important biological activities in hematopoiesis and osteogenesis. However, PEBP2 beta is ubiquitously expressed, suggesting that PEBP2 has other additionally important physiological activities. In an effort to elucidate other possible functions for PEBP2, we have isolated a novel gene that encodes a PEBP2 beta-interacting protein from a mouse cDNA library. We have called this gene Crl-1 for charged amino acid rich leucine zipper-1 (Crl-1) because it is rich in charged amino acids and contains a putative leucine zipper region. Expression studies in a 17.5 days post-coitum mouse embryo demonstrated Crl-1 expression mainly in the olfactory bulb and cerebral cortex. Post-natally, Crl-1 expression was additionally observed in the cerebellar cortex with strong expression in the hippocampus. These findings show that this novel PEBP2 beta-interacting protein is expressed mainly in subsets of neuronal cells, suggesting that Crl-1 plays some role in the developing mouse brain.

Amino Acid Sequence↗

PubMed2001

The Sec protein-translocation pathway.

The Sec machinery (or translocase) provides a major pathway of protein translocation from the cytosol across the cytoplasmic membrane in bacteria. The SecA ATPase interacts dynamically with the SecYEG integral membrane components to drive the transmembrane movement of newly synthesized preproteins. This pathway is also used for integration of some membrane proteins and the Sec translocase interacts with other cellular components to achieve its cellular roles. The detailed protein interactions involved in these processes are being actively studied and a structural understanding of the protein-conducting channel has started to emerge.

Adenosine Triphosphatases↗

PubMed2001

Synthesis and in vivo evaluation of [11C]methyl-Ro 64-6198 as an ORL1 receptor imaging agent.

(1S,3aS)-8-(2,3,3a,4,5,6-Hexahydro-1H-phenalen-1-yl)-3-N-[11C]methyl-1-phenyl-1,3,8-triaza-spiro[4.5]decan-4-one ([11C]methyl-Ro 64-6198), a N-methylated analog of Ro 64-6198, was synthesized and evaluated as a potential radiopharmaceutical for investigating brain nociceptin/orphanin FQ receptors (ORL1 receptors) by positron emission tomography. A racemate of methyl-Ro 64-6198, Ro 66-7931, showed a high affinity and selectivity for the ORL1 receptor in vitro. An in vivo distribution study in mice demonstrated moderate brain uptake, however, only slight difference was observed among brain regions. Furthermore, pretreating with nociceptin or Ro 66-7931 did not affect the accumulation. Therefore, despite its high affinity, [11C]methyl-Ro 64-6198 does not appear to be a suitable tracer for in vivo ORL1 receptor imaging studies.

Animals↗

PubMed2001

Long-term prognosis of patients undergoing transcatheter arterial chemoembolization for unresectable hepatocellular carcinoma: comparison of cisplatin lipiodol suspension and doxorubicin hydrochloride emulsion.

PURPOSE: To evaluate long-term prognosis of transcatheter arterial chemoembolization (TACE) with use of cisplatin (CDDP) lipiodol (LPD) suspension (CDDP/LPD) compared with that with use of doxorubicin hydrochloride (ADM) LPD emulsion (ADM/LPD) in patients with unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: One hundred eight patients were treated with use of CDDP/LPD and 26 were treated with use of ADM/LPD. Survival rates and frequency of side effects and complications in the CDDP/LPD group were compared with those in the ADM/LPD group. RESULTS: CDDP/LPD was given at a dose of 15-70 mg (mean dose, 41 mg), whereas ADM/LPD was given at a dose of 20-100 mg (mean dose, 57 mg) throughout the study period. The survival rates in the CDDP/LPD group were 81% at 1 year, 41% at 3 years, 19% at 5 years, and 13% at 7 years, whereas those in the ADM/LPD group were 67% at 1 year, 18% at 3 years, and 0% at 5 years. The CDDP/LPD group showed significantly better survival than the ADM/LPD group (P <.05). In the CDDP/LPD group, there was a significant prolongation of survival in patients with monofocal HCC (P <.05) and patients with HCC assessed as an almost complete LPD accumulation (P <.05). There were no significant differences in survival rates in the ADM/LPD group according to tumor size and number of tumors. Hepatic failure was observed in 8% of all procedures and was not different between the two therapeutic groups. Renal dysfunction was observed in 2% of all treatments involving CDDP/LPD, and it resolved spontaneously with appropriate medications. CONCLUSIONS: TACE with use of low-dose CDDP was efficacious for unresectable HCC and had few complications. TACE with use of CDDP may contribute to prolongation of the life span of patients with HCC versus TACE with use of ADM.

Aged↗