Biomedical subjects

T Hattori

Publications and source records attributed to T Hattori.

At least 73 records · Page 4Linked to original sources

PubMed2003

Cell kinetic study on histogenesis of Barrett's esophagus using rat reflux model.

BACKGROUND: To elucidate the histogenesis of Barrett's esophagus and esophageal adenocarcinoma, we designed a duodeno-gastric reflux model in which normal stomach function and normal nutritional status are retained. METHODS: Male Wistar rats were used in the experiment. The esophago-gastric junction was side-to-side anastomosed to a loop of jejunum about 3 cm distal to Treitz's ligament. The animals were not exposed to any known carcinogens during the experiment. Sequential morphological changes were studied for up to 50 weeks after surgery. Serial sections were made and stained with hematoxylin and eosin (H&E). In addition, immunohistochemical staining for bromodeoxyuridine (BrdU) was performed along with histochemical staining for mucins using paradoxical concanavalin A (ConA), galactose oxidase Schiff (GOS), and high-iron diamine-alcian blue (HID-AB). RESULTS: Severe esophagitis with squamous cell hyperplasia was noted in all animals after surgery. At week 20 after surgery, glandular metaplastic cells positive for ConA first appeared within the basal cell layer of esophageal squamous cell epithelium, and then GOS-positive cells and HID-AB goblet cells appeared. This is a characteristic of the specialized columnar epithelium of Barrett's esophagus. We detected esophageal adenocarcinomas in 1 out of 8 subjects at week 40 and in 3 out of 8 subjects at week 50 after surgery. CONCLUSIONS: Reflux of duodenal contents causes specialized columnar epithelium of Barrett's esophagus and esophageal adenocarcinoma. As part of the sequence of events leading to the development of Barrett's esophagus, pyloric-foveolar metaplasia was observed followed by the appearance of intestinal goblet cells. The pyloric-foveolar metaplasia appears to be associated with chronic mucosal damage and regeneration. This multiplastic cell lineage is referred to as 'gut-regenerative cell lineage' (GRCL).

Adenocarcinoma↗

PubMed2003

Duodenogastric reflux sustains Helicobacter pylori infection in the gastric stump.

BACKGROUND: Duodenogastric reflux (DGR) and Helicobacter pylori infection have been suspected of being contributing agents to the genesis of gastritis and subsequent cancer, but compelling, conclusive data about the exact relationship have been lacking. METHODS: We investigated the effect of DGR on H. pylori infection in 95 gastrectomized subjects divided into four groups according to type of reconstruction: the jejunal pouch interposition group (JPI, n = 36); the Roux-en-Y group (RY, n = 17); the Billroth I group (B-I, n = 20); and the Billroth II group (B-II, n = 22). The following items were examined for each group: the duration of DGR; the prevalence of H. pylori infection; other bacterial identification and quantity; and the severity of gastritis. RESULTS: The percent of total time of DGR was lower in the JPI (7%) and RY groups (28%) than in the B-I (59%) and B-II groups (88%) (P < 0.02). The prevalence of H. pylori infection was lower in the JPI (28%) and RY groups (29%) than in the B-I (60%) and B-II groups (73%) (P < 0.02). Inversely, the JPI and the RY groups had a higher quantity of other bacteria than the B-I group (P = 0.02). For all four groups, the stomachs infected with H. pylori were fewer than those tested negative for the organism (P < 0.0001). Inflammation scores were lower in both the JPI and RY groups than in the B-I and B-II groups (P < 0.05, respectively). CONCLUSIONS: Duodenogastric reflux facilitates the survival of H. pylori in the gastric stump after a distal gastrectomy.

Adult↗

PubMed2003

Embryonic stem cells injected into the mouse knee joint form teratomas and subsequently destroy the joint.

OBJECTIVE: To determine whether the joint space is a suitable environment for embryonic stem (ES) cells to grow and form cartilage. METHOD: We transplanted ES cells into the knee joint and a subcutaneous space of mice with severe combined immunodeficiency. RESULTS: Teratomas formed in both areas. Those in the joints grew and destroyed the joints. The incidence of cartilage formation was the same in the knee joint and subcutaneous space, but the ratio of cartilage to teratoma was higher in the knee joint than in the subcutaneous space. The teratomas were proved to have been derived from the transplanted ES cells by detection of the neomycin-resistance gene that had been transfected into the ES cells. CONCLUSIONS: It is currently not possible to use ES cells to repair joint tissues. Further optimization of donor ES cells to differentiate as well as inhibit tumour growth may help to meet these challenges.

Animals↗

PubMed2003

Colonic transit time and rectoanal videomanometry in Parkinson's disease.

BACKGROUND: Constipation is a prominent lower gastrointestinal tract dysfunction that occurs frequently in Parkinson's disease (PD). OBJECTIVE: To investigate colonic transport and dynamic rectoanal behaviour during filling and defecation in patients with PD. METHODS: Colonic transit time (CTT) and rectoanal videomanometry analyses were performed in 12 patients with PD (10 men and 2 women; mean age, 68 years, mean duration of disease, five years; mean Hoehn and Yahr grade, 3; decreased stool frequency (<3 times a week) in six, difficulty in stool expulsion in eight) and 10 age matched normal control subjects (7 men and 3 women; mean age, 62 years; decreased stool frequency in two, difficulty in stool expulsion in two). RESULTS: In the PD patients, CTT was significantly prolonged in the rectosigmoid segment (p<0.05) and total colon (p<0.01) compared with the control subjects. At the resting state, anal closure and squeeze pressures of PD patients were lower than those in control subjects, though not statistically significant. However, the PD patients showed a smaller increase in abdominal pressure on coughing (p<0.01) and straining (p<0.01). The sphincter motor unit potentials of the patients were normal. During filling, PD patients showed normal rectal volumes at first sensation and maximum desire to defecate, and normal rectal compliance. However, they showed smaller amplitude in phasic rectal contraction (p<0.05), which was accompanied by an increase in anal pressure that normally decreased, together with leaking in two patients. During defecation, most PD patients could not defecate completely with larger post-defecation residuals (p<0.01). PD patients had weak abdominal strain and smaller rectal contraction on defecation than those in control subjects, though these differences were not statistically significant. However, the PD patients had larger anal contraction on defecation (p<0.05), evidence of paradoxical sphincter contraction on defecation (PSD). CONCLUSIONS: Slow colonic transit, decreased phasic rectal contraction, weak abdominal strain, and PSD were all features in our PD patients with frequent constipation.

Adult↗

PubMed2003

Correlation between change in pulmonary function and suppression of reactive nitrogen species production following steroid treatment in COPD.

BACKGROUND: Reactive nitrogen species (RNS) have a number of inflammatory actions and the production of these molecules has been reported to be increased in the airways of patients with chronic obstructive pulmonary disease (COPD), which suggests that they may be involved in the inflammatory and obstructive process in COPD. METHODS: The relationship between the reduction in RNS and the improvement in pulmonary function was studied in 18 patients with COPD following steroid treatment (800 micro g beclomethasone dipropionate inhalation for 4 weeks). Twelve patients were treated with inhaled steroids and the others received placebo treatment. Forced expiratory volume in 1 second (FEV(1)) and airway responsiveness to histamine were measured before and after treatment. Induced sputum cells were stained with anti-nitrotyrosine antibody, a footprint of RNS, and RNS formation was assessed by measuring nitrotyrosine immunoreactivity. The immunoreactivity of inducible nitric oxide synthase (iNOS) in induced sputum and exhaled NO levels were also measured. RESULTS: Treatment with steroids resulted in a significant reduction in both nitrotyrosine and iNOS immunoreactivity in sputum cells compared with pretreatment levels (both p<0.01). The reduction rates in both parameters were significantly related (p<0.05). The reduction in nitrotyrosine and iNOS immunoreactivity was correlated with the improvement in FEV(1) (p<0.05) and airway responsiveness to histamine (p<0.01). None of the parameters was significantly changed by placebo administration. CONCLUSIONS: These results suggest that RNS may be involved in the reversible component of inflammation in COPD that is suppressed by steroids. Further studies using specific inhibitors for RNS are needed to clarify their effects on the long term progression of COPD.

Administration, Inhalation↗

PubMed2003

A repetitive, steady mouth opening induced an osteoarthritis-like lesion in the rabbit temporomandibular joint.

Although excessive mechanical stress is assumed to be one of the factors contributing to pathogenesis of temporomandibular joint (TMJ) osteoarthritis (OA), no pure mechanical-stress-induced OA model has been developed without surgical manipulation or puncture of the joint cavity. The purpose of this study was to establish a genuine mechanical-stress-induced OA model of the rabbit TMJ. In the experimental rabbits, repetitive, forced jaw-opening, 3 hrs/day for 5 days, was applied with the use of a general anesthesia protocol. By histological assessment of the TMJ articular tissues, partial eburnation of the articular cartilage, reactive marginal proliferation of the articular cartilage chondrocytes, and nested proliferation of chondrocytes in the subchondral bone area were observed at 7 days after the repetitive, forced-jaw-opening period. These results suggest that the repetitive, forced-jaw-opening protocol without surgical intervention can induce evident OA-like lesions in the rabbit TMJ, and this OA model may greatly contribute to the elucidation of the cartilage degradation mechanism in TMJ OA.

Animals↗

PubMed2003

Xanthine oxidase inhibition reduces reactive nitrogen species production in COPD airways.

Reactive nitrogen species (RNS) have been reported to be involved in the inflammatory process in chronic obstructive pulmonary disease (COPD). However, there are no studies on the modulation of RNS in COPD. It was hypothesised that inhibition of xanthine oxidase (XO) might decrease RNS production in COPD airways through the suppression of superoxide anion production. Ten COPD and six healthy subjects participated in the study. The XO inhibitor allopurinol (300 mg x day(-1) p.o. for 4 weeks) was administered to COPD patients. RNS production in the airway was assessed by 3-nitrotyrosine immunoreactivity and enzymic activity of XO in induced sputum as well as by exhaled nitric oxide (eNO) concentration. XO activity in the airway was significantly elevated in COPD compared with healthy subjects. Allopurinol administration to COPD subjects significantly decreased XO activity and nitrotyrosine formation. In contrast, eNO concentration was significantly increased by allopurinol administration. These results suggest that oral administration of the xanthine oxidase inhibitor allopurinol reduces airway reactive nitrogen species production in chronic obstructive pulmonary disease subjects. This intervention may be useful in the future management of chronic obstructive pulmonary disease.

Aged↗

PubMed2003

[The effect of intra-aortic balloon pumping on the graft of coronary artery bypass grafting].

The effect of intra-aortic balloon pumping (IABP) on the graft of coronary artery bypass grafting (CABG) was examined. These patients needed IABP when they were weaned from cardiopulmonary bypass. The flow wave pattern in the graft was acquired and analyze by the slope, peak flow rate and area of systolic phase and diastolic phase. The flow wave pattern different between graft to a left anterior branch and the graft to the right coronary artery. IABP was significantly effective for the flow to the left anterior branch. However, the effect of IABP on the graft flow to the right coronary artery was not significant. In the natural heart, the flow rate of the left coronary artery predominates during the diastolic phase. However this predominance is not clear in the right coronary artery. Our results suggested that this phenomenon in the natural state caused a difference the flow wave pattern between graft of left coronary artery and that of the right coronary artery.

Aged↗

PubMed2002

Properties of human skin mechanoreceptors in peripheral neuropathy.

OBJECTIVES: To investigate the properties of mechanoreceptors in patients with peripheral neuropathy. The skin mechanoreceptor is a terminal organ of the primary sensory neuron, which is likely to be affected earlier and more severely than is the nerve trunk by peripheral neuropathies. METHODS: Single sensory unit responses to air-puff and electric stimulation were recorded using the microneurographic technique in the glabrous skin of the hand. Receptor transduction time was estimated by a latency difference between electric- and air-puff-induced responses. RESULTS: A total of 38 mechanoreceptive units were obtained from 14 normal subjects. All the units responded to air-puff stimuli irrespective of the receptor type, and receptor transduction time was approximately 2 ms. A total of 32 units were recorded from 11 patients with neuropathy of variable causes. Seven (22%) of the 32 neuropathic units did not respond to air-puffs despite their ability to respond to electric stimulation. Compared to normal ones, units from patients with peripheral neuropathy had significantly higher mechanical thresholds, but receptor transduction times did not differ significantly. CONCLUSIONS: Changes in receptor properties in human neuropathy are characterized by increased mechanical threshold without prolongation of receptor transduction time, possibly due to a high threshold for generating receptor potentials.

Aged↗

PubMed2002

Multivariate evaluation of factors affecting recurrence, progression, and survival in patients with superficial bladder cancer treated with intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy: significance of concomitant carcinoma in situ.

To evaluate the relative importance of clinicopathological factors affecting recurrence, progression, and survival in patients with superficial bladder cancer (pTa and pT1) undergoing bacillus Calmette-Guerin (BCG) therapy (Tokyo 172 strain), we reviewed data for 146 patients treated between 1985 and 1998. The median follow-up period was 64.7 months. Tumour recurrence, progression, and death were evaluated as endpoints using Cox's proportional hazards model. The 5-year recurrence-free rate was 56% for all 146 patients. Those with a past history of bladder cancer (n = 73) had significantly earlier recurrence than those without (n = 73, p = 0.017) and this tended to be the case for concomitant CIS (n = 34) although this did not reach statistical significance. The 5-year progression rate was 15% for all 146 patients and univariate analysis revealed that the presence of concomitant CIS was significantly associated with disease progression (p = 0.002). Multivariate analysis using the proportional hazards model confirmed the finding that only one factor, concomitant CIS, was significantly associated with progression. The 5-year survival rate was 84% for all 146 patients. Furthermore, univariate and multivariate analyses revealed that patient age, history of bladder cancer, and concomitant CIS were variables significantly related to patient survival. The present findings suggest that careful follow-up is mandatory after BCG instillation therapy for patients with superficial bladder cancer and concomitant CIS because of their relatively poor prognosis.

Adjuvants, Immunologic↗

PubMed2002

Evaluation of multiple recurrence events in superficial bladder cancer patients treated with intravesical bacillus Calmette-Guérin therapy using the Andersen-Gill's model.

To evaluate factors affecting recurrence after intravesical bacillus Calmette-Guérin (BCG) therapy (Tokyo 172 strain), we reviewed data for 101 patients with superficial bladder cancer (pTa [n = 80] and pT1 [n = 21]) treated between 1985 and 1999. The median follow-up period was 58.9 months. Factors affecting the first tumour recurrence were evaluated using Cox's proportional hazards model and those affecting multiple recurrence with Andersen-Gill's model. The 5-year recurrence-free rate was 63% for all 101 patients. The recurrence frequency, defined as times per 100 patient-months of follow-up, greatly decreased from 7.3 +/- 9.6 (SD) before the instillation to 2.6 +/- 5.6 after the therapy (p < 0.0001). Patients with pT1 tumours tended to have earlier recurrence than those with pTa tumours (p = 0.06). Multivariate analysis using Cox's proportional hazards model revealed that a history of bladder cancer and pathological stage were independent factors affecting the first tumour recurrence after the BCG therapy. When multiple endpoints of recurrence were evaluated using the Andersen-Gill's model, number of tumours as well as a history of bladder cancer and pathological stage demonstrated significant links to tumour recurrence after the BCG therapy. The 5-year progression-free and 5-year survival rates were 89.3% and 85.3% for all the 101 patients, respectively. Because intravesical recurrence may involve multiple events during the clinical course of patients with bladder cancer, the Andersen-Gill's model appears useful for evaluation of risk factors.

Adjuvants, Immunologic↗

PubMed2002

A patient homozygous for the SCA6 gene with retinitis pigmentosa.

The present authors studied a 55-year-old-patient homozygous for the SCA6 gene who experienced frequent attacks of positional vertigo at 37 years of age with subsequent staggering gait and night blindness. Retinitis pigmentosa (RP), as well as cerebellar ataxia and vertical antidirectional nystagmus, were detected. The subject's parents were first cousins, and two of his three male cousins, whose parents were also first cousins, had RP without ataxia or nystagmus. The numbers of CAG repeats in the expanded alleles of the SCA6 gene found by molecular analysis were 21 and 21. The genetic results were negative for SCA1, SCA2, SCA3, SCA7 and dentatorubral pallidoluysian atrophy. The retinal degeneration in this patient is most likely to be secondary to a genetic disorder of autosomal or X-linked recessive inheritance rather than SCA6. Other reported cases of patients homozygous for the SCA6 gene are also reviewed.

Calcium Channels↗

PubMed2002

Autonomic function in demyelinating and axonal subtypes of Guillain-Barré syndrome.

OBJECTIVES: To investigate whether or not the pattern and extent of autonomic involvement differ between the two subtypes of Guillain-Barré syndrome (GBS), namely acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). METHODS: Head-up tilt test, R-R interval variation, plasma noradrenaline concentration, skin vasomotor reflex (SVR) and sympathetic sweat response (SSwR) were used to estimate autonomic function in seven AIDP and eight AMAN patients. RESULTS: Heart rate and plasma noradrenaline concentration were significantly high in the AIDP group but not in the AMAN group. Skin vasomotor reflexes were generally preserved and SSwRs were impaired in patients with severe neurological deficits for both AIDP and AMAN groups. CONCLUSION: The patterns of autonomic involvement are qualitatively different between AIDP and AMAN. Acute inflammatory demyelinating polyneuropathy is characterized by cardio-sympathetic hyperactivity, excessive or reduced sudomotor function and preserved skin vasomotor function, while AMAN is not necessarily generally associated with marked autonomic dysfunction except for the sudomotor hypofunction seen in patients with severe neurological deficits.

Adult↗

PubMed2002

Proliferative effects of eosinophil lysates on cultured human airway smooth muscle cells.

BACKGROUND: The hypertrophy/hyperplasia of airway smooth muscle (ASM) cells is one of the characteristic features of bronchial asthma. This structural change leads to the thickening of airway walls resulting in the amplification of airway narrowing. However, the pathogenesis of this structural change has not yet been determined. Eosinophils, which play a pathogenic role in asthma, have been demonstrated to have proliferative effects on fibroblasts and vascular smooth muscle cells. OBJECTIVE: We attempted to investigate the potential of eosinophils to induce the proliferation of ASM cells. METHODS: We examined the effect of lysates of eosinophils purified from peripheral blood of healthy donors on cultured human ASM cell proliferation. RESULTS: Eosinophil lysates significantly induced ASM cell proliferation in time- and dose-dependent manners, reaching a maximum on day 6 at 50% of eosinophil lysates (6.0 +/- 0.7 x 104 [mean +/- SD] /well, n = 5 vs. 4.5 +/- 1.1 x 104/well, n = 5; P < 0.05). This proliferative activity was heat-sensitive and recovered in the soluble fraction of the eosinophil lysates. Furthermore, the molecular weight of the mitogenic activity in the soluble fraction was identified as lower than 10 kDa. The inhibitory activity to ASM cell proliferation was also found in the insoluble fraction of the lysates. CONCLUSION: These results indicate that circulating eosinophils store mitogenic activity for ASM cells, suggesting that eosinophils might contribute to the development of the hyperplasia of ASM cells in asthmatics through the release of the stored mitogenic activity upon stimulation at the site of inflammation.

Aged↗

PubMed2002

Gastric mucosal atrophy: interobserver consistency using new criteria for classification and grading.

BACKGROUND AND AIMS: Considerable difficulties persist amongst pathologists in agreeing on the presence and severity of gastric atrophy. An international group of pathologists pursued the following aims: (i) to generate an acceptable definition and a simple reproducible classification of gastric atrophy; and (ii) to develop guidelines for the recognition of atrophy useful for increasing agreement among observers. METHODS: After redefining atrophy as the 'loss of appropriate glands' and examining histological samples from different gastric compartments, three categories were identified: (i) negative; (ii) indefinite; (iii) atrophy, with and without intestinalization. Atrophy was graded on a three-level scale. Interobserver reproducibility of the classification was tested by kappa statistics (general and weighted) in a series of 48 cases. RESULTS: The medians of the general agreement and weighted kappa values were 0.78 and 0.73, respectively. The weighted kappa coefficients, obtained by cross-tabulating the evaluation of each pathologist against all others, were, with only one exception, > 0.4 (moderate to excellent agreement). CONCLUSIONS: By using the definition of atrophy as the loss of appropriate glands and distinguishing the two main morphological entities of metaplastic and non-metaplastic types, a high level of agreement was achieved by a group of gastrointestinal pathologists trained in different cultural contexts.

Atrophy↗

PubMed2002

The involvement of matrix metalloproteinases in basement membrane injury in a murine model of acute allergic airway inflammation.

BACKGROUND: Airway remodelling in asthma such as subepithelial fibrosis is thought to be the repair process that follows the continuing injury as of chronic airway inflammation. However, how acute allergic inflammation causes tissue injury in the epithelial basement membrane in asthmatic airways remains unclear. Matrix metalloproteinases (MMPs) capable of degrading almost all of the extracellular matrix components have been demonstrated to be involved in cell migration through the basement membrane in vivo and in vitro. OBJECTIVE: We investigated the alterations of matrix construction and the role of MMPs in matrix degradation in the subepithelium during acute allergic airway inflammation. METHODS: Airway inflammation, the ultrastructure of the subepithelium and injury of types III and IV collagen in tracheal tissues from ovalbumin (OVA)-sensitized mice after OVA inhalation with or without the administration of tissue inhibitor of metalloproteinase-2 (TIMP-2) and dexamethasone were evaluated by cell counting in bronchoalveolar lavage (BAL) fluids, electron microscopy and immunohistochemistry, respectively. RESULTS: The disruption of the lamina densa and matrix construction and the decrease of the immunoreactivity for type IV collagen in subepithelium were observed in association with the accumulation of inflammatory cells in airways 3 days after OVA inhalation. This disorganization of the matrix components in the subepithelium, as well the cellular accumulation, was abolished by the administration of TIMP-2 and dexamethasone. The immunoreactivity for type IV collagen in the subepithelium in OVA-inhaled mice returned to the level of that in saline-inhaled mice 10 days after inhalation in association with a decrease of the cell numbers in the BAL fluid. The immunoreactivity for type III collagen was changed neither 3 nor 10 days after OVA inhalation. CONCLUSION: These results suggest that epithelial basement membrane gets injured by, at least in part, MMPs as a consequence of cell transmigration through the membrane during acute allergic airway inflammation.

Acute Disease↗

PubMed2002

Homozygous Machado-Joseph disease presenting as REM sleep behaviour disorder and prominent psychiatric symptoms.

A male patient carrying the homozygous gene for Machado-Joseph disease (MJD) presented at age 43 with sleep disturbances and psychiatric symptoms followed by ataxic speech and gait. A polysomnogram (PSG) showed decreased rates of sleep time and stage rapid eye movement (REM) and an increased rate of 'stage 1-REM with tonic EMG' (Tachibana et al., 1975); all compatible with REM sleep behaviour disorder (RBD). Molecular gene analysis at age 59 showed that the CAG repeat units in the MJD gene were 60 and 60, smaller than the reported lengths for homozygous MJD patients (63-70 and 66-72). In addition to sleep disturbances, in particular RBD, psychiatric symptoms may be important clinical features in both heterozygous and homozygous MJD.

Diagnosis, Differential↗

PubMed2002

Efficient selection of genomic clones from a female chicken bacterial artificial chromosome library by four-dimensional polymerase chain reactions.

A bacterial artificial chromosome (BAC) library consisting of 49,152 genomic clones was constructed from partially HindIII-digested female chicken embryo genomic DNA using the pBAC-Lac vector and maintained in 512 96-well plates. The mean insert size was approximately 150 kb, and the total library was estimated to contain about 3.2 times coverage of the diploid genome. In order to screen this library by the PCR, 296 BAC clone DNA samples were prepared: one sample each from 8 superpools (64 plates per superpool) and 36 samples of four-dimensionally (4-D) mixed clones from each superpool. A BAC clone of interest was selected by two-step PCR. First, 8 DNA samples representing superpools were subjected to PCR with a set of primers to amplify a part of the genomic sequence of interest. Second, 36 4-D DNA samples from the superpool that contained BAC clone(s) of interest were subjected to PCR with the same set of primers. The second step identified a plate and a well containing the BAC clone of interest. Selection of target BAC clone(s) from the whole library with the above procedure can be achieved within 1 to 4 d without using a radioactive probe. This procedure was applied successfully in the selection of BAC clones for Wpkci, chPKCI/HINT, ZOV3, and 17beta-HSD genes.

Amino Acid Sequence↗