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Biomedical subjects

T Honda

Publications and source records attributed to T Honda.

At least 127 records · Page 7Linked to original sources
PubMed2000

Sensory innervation of the lumbar dura mater passing through the sympathetic trunk in rats.

STUDY DESIGN: Sensory innervation of the lumbar dura mater passing through the sympathetic trunk was investigated by neuronal tracing and immunohistochemical methods. OBJECTIVE: To assess an anatomic basis indicating that sympathetic block in the higher lumbar region is effective for patients with low back pain. SUMMARY OF BACKGROUND DATA: Low back pain is elicited by disorder or mechanical stimulation of the lumbar dura mater. Clinically, the authors often have observed patients in whom root block at the responsible level or sympathetic block at the higher level could relieve low back pain. Therefore, there may be two different sensory routes, the segmental innervation at the same level and nonsegmental fibers from higher dorsal root ganglia. METHODS: The tracers were injected into the sympathetic trunk between L3 and L4 of rats. The lumbar dorsal root ganglia and dura mater were examined, and labeled cells were measured in size and the distribution. To establish the sensory property, the materials were processed in immunohistochemistry for calcitonin gene-related peptide. RESULTS: Many small- to medium-sized neurons were retrogradely labeled L1 and L2 dorsal root ganglia after injection into the sympathetic trunk. The anterogradely labeled fibers were found in the dura mater at L4 and L5. Some of the labeled neurons and fibers were immunoreactive for calcitonin gene-related peptide. CONCLUSION: Sensory fibers from the upper lumbar ganglia innervated the lower lumbar dura mater directly. These sensory nerves may mediate low back pain and possibly interact with sympathetic nerves.

Animals↗
PubMed2000

Proteolytic processing and degradation of human presenilin-1 expressed in yeast.

Numerous mutations causing early-onset familial Alzheimer's disease have been identified in the presenilin-1 gene. Presenilin-1 protein is produced as a 47 kDa holoprotein and proteolytically processed to an N-terminal 28 kDa and a C-terminal 19 kDa fragments by unidentified presenilinase in mammalian cells. We have demonstrated that this proteolytic processing also occurs in yeast. We also show that degradation of C-terminal fragment of presenilin-1 is dependent of proteasomal function. This yeast system will be a good tool to identify presenilinase and to study the role of presenilin-1 in amyloid precursor protein processing.

Blotting, Western↗
PubMed2000

Expression of coxsackievirus and adenovirus receptor in hearts of rats with experimental autoimmune myocarditis.

The expression of coxsackievirus and adenovirus receptor (CAR) was dominant in the brains and hearts of mice until the newborn phase. There is no detailed information concerning the relation between the expression of CAR and development of hearts. It is also uncertain whether CAR is able to be induced in adult hearts after cardiac injury. We demonstrated that CAR was abundant in the hearts of newborn rats but was barely detectable in the hearts of adult rats. The expression of CAR in rat hearts with experimental autoimmune myocarditis, which was induced by immunization of purified cardiac myosin, was serially investigated. Active myocarditis was observed from day 15 after immunization. By immunohistochemistry, cardiomyocytes were strongly stained for CAR antibody from days 24 to 42. CAR mRNA was also detected from days 18 to 30 by using reverse transcription-polymerase chain reaction. In the next experiment, the induction of CAR on isolated cardiomyocytes was investigated. CAR was barely detectable in cultured cardiomyocytes by Western blot analysis after isolation. This molecule gradually appeared along with the creation of clusters and beating of cardiomyocytes. Furthermore, the induction of CAR in cultured cardiomyocytes increased after supplement with conditioned medium of rat splenocytes activated by concanavalin A. In conclusion, rat CAR is expressed strongly in the hearts of newborn rats and is suppressed in those of adult rats. The expression of CAR is enhanced during the active phase of experimental autoimmune myocarditis and is induced by inflammatory mediators. CAR may play a role in cell-to-cell contact and adhesion of cardiomyocytes.

Aging↗
PubMed2000

Type II pneumocytes are preferentially located along thick elastic fibers forming the framework of human alveoli.

Type II pneumocytes were found to be preferentially located on thick elastic fibers which formed the main structural framework of the alveoli in humans. Eight lobes resected from eight patients with adenocarcinoma or atypical adenomatous hyperplasia and two lobes from two necropsies were examined. Four small specimens of normal lung tissue were obtained from each lobe fixed in a buffered formalin. Thick sections (200-300 microm) were stained with hematoxylin to contrast nuclei or with elastica staining to demonstrate elastic fibers and immunostained with an antibody against Thomsen-Friedenreich antigen after pretreatment with sialidase to visualize type II pneumocytes. Alveolar structure and the distribution of type II pneumocytes were examined in 3D reconstructions generated using a standard microscope, a personal computer and NIH-Image software. Nuclei including those of type I and type II pneumocytes and endothelial cells were distributed diffusely throughout the alveolar wall. Thick elastic fibers constructed the main structural framework of the alveoli and formed the sides of the polygonal alveoli. Type II pneumocytes were found to be linearly located along these thick elastic fibers. This previously undisclosed distribution of type II pneumocytes may be concerned with alveolar rapid movement.

Adult↗
PubMed2000

Increased sinusoidal pressure is associated with early liver weight gain in ischemia-reperfusion injury in isolated perfused rat liver.

BACKGROUND: Hepatic ischemia-reperfusion (I/R) is accompanied by liver weight gain and ascites formation. This could be caused by an increase in sinusoidal pressure, a determinant of hepatic transvascular fluid movement. We determined the role of sinusoidal pressure, assessed by triple vascular occlusion pressure (P(to)), in the I/R injury in isolated rat livers perfused with leukocyte-free diluted blood bivascularly via the portal vein and hepatic artery. MATERIALS AND METHODS: Ischemia was induced at room temperature by occlusion of either the inflow lines of the hepatic artery and portal vein (the open outflow group, n = 10) or both the inflow and the outflow (hepatic venous) lines (the closed outflow group, n = 10) for 1 h, followed by 1-h reperfusion in a recirculating manner. RESULTS: Liver weight in both groups increased biphasically after reperfusion; the initial peak occurred at 3 min and the second peak at 60 min. Immediately after reperfusion, P(to) peaked, followed by a gradual decline. The initial weight increase in groups combined was significantly and positively correlated with an increase in P(to) (r = 0.716, P = 0.0002), but the second peak was independent of P(to). Liver injury, assessed by perfusate levels of hepatic enzymes and reduced bile flow rate, was observed at 60 min after reperfusion in both groups. CONCLUSIONS: These findings suggest that increased sinusoidal pressure contributes to only the early liver weight gain after reperfusion in isolated perfused rat livers. The late weight gain may be presumably due to liver injury.

Animals↗
PubMed2000

Induction of determinant spreading and of Th1 responses by in vitro stimulation with HER-2 peptides.

Immunization with tumor antigens induces cellular and humoral immune responses. These responses by T cells are specific for defined epitopes (determinants) in the molecule of the immunizing tumor antigen. Extension of such responses to self-antigens requires induction of autoimmunity to the tumor. As with systems of autoimmune disease, expression of T cell autoimmunity is charaterized by diversification of responses from the inducer determinant to other responder (cryptic) determinants. Since similar strategies may be useful for therapy of human cancers, we investigated whether the induction of response to a HER-2 peptide F7 (776-789) induces enhanced reactivity of other HER-2 peptides. We found that stimulation with F7 can expand a response to another epitope F13 (884-899) in both an ovarian cancer patient with progressive disease and a healthy donor who shared HLA-DR11. This response was characterized mainly by increased interferon gamma secretion, and proliferation, but was not observed with another donor who shared HLA-DR14 and HLA-DQ5 with the patient. Since repeated vaccination with the same epitope may lead to a decline of primary cell reactivity caused by apoptosis spreading the response to other epitopes, the tumor antigen may provide an approach for maintaining an inflammatory Th1 response during cancer vaccination.

Antigens, Neoplasm↗
PubMed2000

Correlation between high-resolution computed tomographic, magnetic resonance and pathological findings in cases with non-cancerous but suspicious lung nodules.

Computed tomography scans, including thin-section high-resolution computed tomography (HRCT), occasionally fail to differentiate between small non-cancerous nodules from lung cancers. We describe nine such lesions ( < 20 mm in diameter) initially identified through our screening program for lung cancer using CT scanning. Pathological diagnoses included nodular fibrosis (n = 4), granuloma (n = 1), cryptococcoma (n = 1), localised organising pneumonia (n = 1), inflammatory pseudo-tumour (n = 1) and sclerosing haemangioma (n = 1). High-resolution CT findings, together with MRI findings with contrast-enhanced dynamic studies, were retrospectively evaluated. Additional cases should be identified and radiologically characterised in order to reduce the number of non-cancerous tumours that are treated by unnecessary surgery.

Aged↗
PubMed2000

Corneal infection of herpes simplex virus type 2--induced neuronal apoptosis in the brain stem of mice with expression of tumor suppressor gene (p53) and transcription factors.

To understand the mechanism of neuronal apoptosis induced by herpes simplex virus (HSV) infection in vivo, the distribution of viral antigen, the appearance of apoptotic bodies, and the expressions of the tumor suppressor gene p53 and several transcription factors such as c-fos, c-jun and NF-kappaB were examined immunohistochemically and histopathologically after corneal infection of mice with HSV type 2 strain 186. Five days after HSV infection, viral antigen was diffusely detected in the corneal epithelium, the trigeminal ganglion and the pars caudalis of the spinal trigeminal nucleus. Neuronal apoptosis was observed in the brain stem ipsilateral to the HSV-infected side with the immunoreactivities of c-fos, c-jun, NF-kappaB and p53. Dual-labeling immunohistochemical studies revealed that almost all of the viral antigen-positive neurons and glia in the brain stem also showed p53 immunoreactivity. On the other hand, no neuronal apoptosis but only with the expression of c-jun was found in the trigeminal ganglion. Our results suggest that the different expression of transcription factors between the brain stem and the trigeminal ganglion may influence the neuronal apoptosis induced by HSV infection.

Afferent Pathways↗
PubMed2000

Basal layer reactivity in hyperplastic and metaplastic lesions of the bronchi as studied by lectin histochemistry.

The relationship between squamous metaplasia and squamous cell carcinoma of the bronchi has been the subject of controversy. We investigated basal cell hyperplasia, stratification, squamous metaplasia, and squamous cell carcinoma by means of lectin histochemistry with peanut agglutinin (PNA), Ulex europeus agglutinin-I, soybean agglutinin, and Dolichos biflorus agglutinin for all normal basal cells that are reactive. A basal layer stained with PNA was observed in basal cell hyperplasia, stratification, and squamous metaplasia, but this layer was not exhibited by squamous cell carcinoma. In hyperplasia and metaplasia, PNA staining was biased toward the lowest (basal) layer, whereas staining for the other lectins was more uniformly distributed across the layers. A PNA-positive basal layer may be important for the morphologic reversibility of the bronchial mucosa in hyperplastic and metaplastic lesions, and destruction of this layer may be associated with a progression from metaplasia to squamous cell carcinoma.

Adenocarcinoma↗
PubMed2000

Double cancer (lung and colon cancer) that showed complete remission with irinotecan and cisplatin combined chemotherapy.

We report a rare case of double (colon and lung) cancer which showed complete remission with chemotherapy with irinotecan (CPT-11) and cisplatin (CDDP). The patient was a 67-year-old man who was diagnosed as having double cancer (stage IIIb pulmonary adenocarcinoma and stage 0 [or 1] well-differentiated adenocarcinoma of the ascending colon). Two courses of chemotherapy (CPT-11, 60 mg/m2, days 1 and 8; CDDP, 30 mg/m2, days 1 and 8) were performed. The combination therapy of CPT-11 and CDDP was very effective. In Japan, there have been few published reports describing the use of CPT-11 for the treatment of gastrointestinal cancer. We think that the use of CPT-11 in gastrointestinal cancer is promising.

Adenocarcinoma↗
PubMed2000

Experimental study of an artificial esophagus using a collagen sponge, a latissimus dorsi muscle flap, and split-thickness skin.

The time and effort spent trying to devise an artificial esophagus have not yet resulted in success, and leakage and strictures at the anastomotic sites remain the most frequent complications. We developed an artificial esophagus with a bilayered structure made of porous collagen sponge (artificial dermis; AD), a latissimus dorsi muscle flap (LD), and split-thickness skin (STS). We investigated whether the use of AD prevented the contraction of grafted skin and its effects on the extensibility of the neoesophagus in rabbits. We experimented with two groups. In the AD group, AD was applied to the surface of the LD. Three weeks later, the STS was grafted. In the control group, the STS was grafted directly onto the LD. The sizes of the STS in both groups 3 weeks after the graft were, respectively, 56.6% +/- 4.1% and 39.0% +/- 10.2% of the initial surface area of the STS (P < 0.01). The roll made in the AD group had better extensibility than that in the control group. We replaced the cervical esophagus in 12 rabbits with the neoesophagus made from AD, STS, and LD. The longest survival period was 16 days. Esophagography did not reveal either anastomotic leakage or stenosis in any of the five rabbits in the experiments. These findings suggested that AD can thus be used to create a more suitable hybrid artificial esophagus.

Animals↗
PubMed2000

Anthocyanins in callus induced from purple storage root of Ipomoea batatas L.

Two anthocyanins were isolated from the highly pigmented callus derived from the storage root of purple sweet potato (Ipomoea batatas L.) cultivar 'Ayamurasaki'. One was identified as cyanidin 3-O-sophoroside-5-O-glucoside, and the other as cyanidin 3-O-(2-O-(6-O-(E)-p-coumaroyl-beta-D-glucopyranosyl)-beta-D-glucop yranoside)-5-O-beta-D-glucopyranoside, by chemical and spectroscopic analysis.

Anthocyanins↗
PubMed2000

Pulmonary artery remodeling modifies pulmonary hypertension during exercise in severe emphysema.

To clarify the relation between the vessel remodeling and the physiology of pulmonary circulation in chronic obstructive pulmonary disease (COPD), we studied the pulmonary hemodynamics at rest and during exercise (25W) and the morphology of pulmonary arteries with external diameters of 100-200 microm in ten patients with severe emphysema. The wall thickness (WT) was defined as the intima plus media. The percent WT of the external diameter (% WT) in emphysema (36.0 +/- 4.3%) was significantly increased compared with that (22.6 +/- 3.3%) in five control lungs. The % WT was not related to pulmonary arterial pressure (Ppa) at rest, but was highly correlated with exercise Ppa (r = 0.721, P = 0.02) and with deltaPpa (Ppa during exercise-Ppa at rest) (r = 0.899, P = 0.0004). These findings suggest that pulmonary artery remodeling leads to reduced recruitability and distensibility of pulmonary vessels and is closely related to exercise pulmonary hypertension.

Aged↗
PubMed2000

Familial Alzheimer's disease-associated mutations block translocation of full-length presenilin 1 to the nuclear envelope.

A polyclonal antibody, M5, to the hydrophilic loop domain of human presenilin 1 (PS1) was prepared. Western blot and immunoprecipitation analyses showed that M5 specifically recognized the processed C-terminal fragment, but not the full-length PS1. Epitope mapping analysis revealed that the essential sequence for recognition of the C-terminal fragment by M5 is DPEAQRR (302-308). The recognition of the C-terminal fragment by M5 in a processing-dependent manner was further confirmed by competitive enzyme-linked immunosorbent assay using the synthetic peptide L281 (281-311), which contains the putative processing site and the preceding amino acids to the site. Although L281 contains the epitope sequence for M5, the maximum inhibition was only 14%. Immunocytochemistry using M5 combined with hL312, which recognizes both full-length PS1 and the C-terminal fragment, allowed us to distinguish the localization of the processed C-terminal fragment from that of full-length PS1. Confocal microscopy demonstrated that the full-length form of wild-type PS1 is preferentially located in the nuclear envelope, while the processed C-terminal fragment is mainly present in the endoplasmic reticulum (ER). However, PS1 with familial Alzheimer's disease-associated mutations could not translocate to the nuclear envelope, and both the full-length and processed mutants were co-localized in the ER.

Alzheimer Disease↗
PubMed2000

Suppressive effects of Neiting acupuncture on toothache: an experimental analysis on Fos expression evoked by tooth pulp stimulation in the trigeminal subnucleus pars caudalis and the periaqueductal gray of rats.

To clarify the antinociceptive mechanism of acupuncture on acute pain, c-fos protein (Fos) expression induced by tooth pulp stimulation was immunohistochemically examined in the spinal trigeminal subnucleus pars caudalis (spVc) and the periaqueductal gray (PAG) of rats with or without Neiting acupuncture. The central projection of trigeminal ganglion neurons innervating in the tooth pulp was examined by tract-tracing method with horseradish peroxidase-conjugated wheat germ agglutinin (WGA-HRP). Central terminals from the first maxillary molar tooth were labeled transganglionically in the dorsomedial part of spVc with WGA-HRP. Numerous numbers of Fos-immunoreactive (Fos-ir) cells were found in the spVc and PAG by stimulation of the tooth pulp with acetic acid or saline. Neiting acupuncture significantly reduced the Fos expression in the spVc induced by tooth pulp stimulation. On the other hand, Neiting acupuncture evoked many Fos-ir cells in the PAG. The present results suggest that Neiting acupuncture activated PAG neurons that sent descending inhibitory fibers to medullo-spinal nociceptive neurons, and reduced the number of Fos-expressed neurons in the trigeminal subnucleus pars caudalis mediating noxious information from teeth to the higher central nervous system.

Acupuncture Analgesia↗
PubMed2000

Successful treatment of a case of electrical burn with visceral injury and full-thickness loss of the abdominal wall.

A 13-year-old male received high-voltage electrical burns with a resultant large direct wound on the upper abdomen involving the full-thickness of the abdominal wall, including the peritoneum. Early debridement, exploratory laparotomy and temporary restoration of the excised abdominal wall with a fascial prosthesis were carried out at 6 h post-burn. The bilateral upper and right lower limbs were amputated on the 10th post-burn day. The patient developed a 4x4 cm duodenocutaneous fistula on the 28th post-burn day, but was free of peritonitis. After 5 months of the conservative treatment, the fistula closed, and the abdominal wall defect was reconstructed with a free latissimus dorsi musculocutaneous flap. One month later, the patient was discharged following an uneventful recovery.

Abdominal Muscles↗