Biomedical subjects

Y Horiguchi

Publications and source records attributed to Y Horiguchi.

At least 109 records · Page 6Linked to original sources

PubMed1994

Sevoflurane and isoflurane protect against bronchospasm in dogs.

BACKGROUND: Halothane and isoflurane have been shown to be effective in reversing bronchoconstriction; however, the effects of sevoflurane have not been well defined. We studied whether sevoflurane, compared with isoflurane, attenuates bronchospasm in dogs. METHODS: Twenty-four dogs sensitized to Ascaris suum were assigned to three groups: control (n = 8), sevoflurane (n = 8), or isoflurane (n = 8). In all dogs, anesthesia was induced with pentobarbital. In the sevoflurane and isoflurane groups, the volatile anesthetics were administered at an end-tidal anesthetic concentration of 1 MAC throughout the study. After measurement of pulmonary resistance (RL) and dynamic pulmonary compliance (Cdyn) at baseline, A. suum antigen was administered intravenously into the systemic circulation to induce anaphylaxis, and RL and Cdyn were recorded continuously for 120 min after antigen challenge. RESULTS: Effects on RL and Cdyn were maximal 5 min after the start of systemic administration of antigen in all groups. Both 1 MAC sevoflurane and 1 MAC isoflurane significantly attenuated the increase in RL provoked by antigen challenge, but the attenuation from 10 to 15 min after challenge in the sevoflurane group was not significantly different from that in the control group. There was no significant difference in RL between sevoflurane and isoflurane. For both sevoflurane and isoflurane, attenuation of the decrease in Cdyn was not statistically significant. There was no significant difference in Cdyn between sevoflurane and isoflurane. CONCLUSIONS: Sevoflurane is as effective as isoflurane in attenuating bronchoconstriction associated with anaphylaxis in dogs. Sevoflurane may be a useful alternative to halothane, enflurane, or isoflurane in the treatment of bronchospasm in asthma or anaphylaxis.

Anesthetics↗

PubMed1994

Production of nitric oxide in anaphylaxis in rabbits.

To verify production of nitric oxide (NO) in anaphylaxis, we measured NO in peripheral tissue in anaphylactic rabbits using an NO-sensitive electrode. Rabbits were sensitized to horse serum, which was later administered over 10 s into the systemic circulation to induce anaphylaxis. Blood pressure (BP), central venous pressure (CVP), heart rate, and NO were recorded continuously for 80 min after antigen challenge. The NO-sensitive electrode was placed between the superficial abdominal fascia and the rectus abdominis fascia. The NO concentration increased to 3000-4800 pA (about 3-4.8 microM NO) within 4 min after initiation of anaphylaxis, at which time BP was decreased and CVP increased; however, NO production was continuously observed 30-60 min after antigen challenge, during which time changes in BP and CVP were not correlated with changes in NO concentration. In conclusion, NO production can be detected using an NO-selective electrode in anaphylactic rabbits.

Anaphylaxis↗

PubMed1994

Leukotriene A4 hydrolase in human skin.

The biochemical properties and immunohistochemical localization of leukotriene (LT) A4 hydrolase were investigated in human skin. The activity of LTA4 hydrolase, which catalyzes the hydrolysis of LTA4 to LTB4, the most chemotactic compound known, was detected in the 100,000 x g supernatant of homogenates of human epidermis and a transformed epidermal cell line (HSC-1). No significant LTA4 hydrolase activity was detected in human whole skin or dermis. The enzymatic properties of LTA4 hydrolase isolated from human keratinocytes and peripheral leukocytes were similar. Their activities were inhibited by bestatin and captopril, and they were completely absorbed by anti-human LTA4 hydrolase antibody. By immunoblotting analysis using this antibody, LTA4 hydrolase was detected as a 70-kDa protein in human epidermis and HSC-1 and was found to be similar to the enzyme detected in peripheral mononuclear leukocytes. In human dermis, LTA4 hydrolase was barely detected by Western blotting. On the other hand, LTA4 hydrolase was demonstrated in the cytoplasm of keratinocytes in the epidermis, and in fibroblasts, infiltrating and endothelial cells in the dermis of normal human skin by immunohistochemical analysis using the immunoperoxidase method. These results suggest that LTB4 can be generated from LTA4 by LTA4 hydrolase in keratinocytes as well as fibroblasts, infiltrating and endothelial cells in the dermis of human skin.

Blotting, Western↗

PubMed1994

A case of linear IgA bullous dermatosis with atypical clinical and ultrastructural manifestations.

We report a case of linear IgA bullous dermatosis which presented with atypical clinical and ultrastructural findings. The patient initially manifested small, subepidermal blisters scattered only in the seborrheic region. On follow-up, grouped vesicles developed in a circular form similar to dermatitis herpetiformis. They subsided after treatment with diaminodiphenyl sulphon. Immunofluorescent study showed predominant linear IgA deposits accompanied with IgG and C3 along the basement membrane zone. These deposits existed at the floor of the blister. Ultrastructurally, immunoreactants were demonstrated beneath the lamina densa while separation occurred at lamina lucida.

Humans↗

PubMed1994

Cadherins in cutaneous biology.

The role of cadherins in cutaneous biology has focused mainly on the classical cadherins, E- and P-cadherin. In this review, roles for cadherins in skin morphogenesis, keratinocyte differentiation, and cancer metastasis are discussed. E-cadherin is expressed on the surfaces of whole epidermal layer cells, and P-cadherin is expressed only on the surfaces of basal cells. Ultrastructural studies have shown that E-cadherin is distributed on the cytoplasmic membranes of keratinocytes with a condensation in the intercellular space of the desmosomes. During human skin development, P-cadherin expression is spatiotemporally controlled and closely related to the segregation of basal layers as well as to the arrangement of epidermal cells into eccrine ducts. In human skin diseases, E-cadherin expression is markedly reduced on the acantholytic cells of tissues in pemphigus and also in Darier's disease. Keratinocytes cultured in high calcium produce a much more intense immunofluorescence of intercellular E- and P-cadherin than do cells grown in low calcium. Ultrastructural studies show that E-cadherin on the cytoplasmic membrane of the keratinocytes is shifted to desmosomes under physiological conditions and therein expresses an adhesion function is association with other desmosomal cadherins. Cell adhesion molecules are now considered to play significant roles in the cellular connections of cancers and metastatic cells. Reduced expression of E-cadherin on invasive neoplastic cells has been demonstrated for cancers of the stomach, liver, breast, and several other organs. This reduced expression of E-cadherin is observed in squamous cell carcinoma and Paget's disease. Soluble E-cadherins in sera are elevated in various skin diseases, including bullous pemphigoid, pemphigus vulgaris and psoriasis, but not in patients with burns. Markedly high levels in soluble E-cadherin are demonstrated in patients with metastatic cancers.

Cadherins↗

PubMed1994

Noninvasive quantitative evaluation of the morphology of the major pulmonary artery branches in cyanotic congenital heart disease. Angiocardiographic and echocardiographic correlative study.

BACKGROUND: Precise noninvasive evaluation of pulmonary artery (PA) morphology is extremely important for medical and surgical management of patients with cyanotic heart disease. In this study, the accuracy of two-dimensional echocardiography combined with color Doppler flow mapping to assess the size, stenosis, and atresia of the major PA branches was examined using a new parasternal approach. METHODS AND RESULTS: With the use of right and left high parasternal windows, we visualized each of the major portions along the right (R-PA) and left (L-PA) pulmonary arteries in 45 of the 47 examinations (96%) in 38 patients with cyanotic heart disease. The patients were between 13 days and 20 years old (mean age, 2.9 years). The internal diameters of the major PA branches were measured at three points along the R-PA (the proximal, mid, and distal portions) and at the proximal and distal portions on the L-PA in systole by both two-dimensional echocardiography and angiography. In addition, the diameter of the stenosis in the PA branch was measured. These PA values as determined by two-dimensional echocardiography correlated well with those obtained by angiography (r = .95 to .97). By two-dimensional echocardiography with color Doppler flow mapping, 17 of 19 lesions with stenoses or atresia of the major PA branches were predicted as defined by angiography (sensitivity, 89.5%; specificity, 100%). Differences between the distal parts of the L-PA and R-PA of > 30% in diameter were determined by angiography in 15 examinations and by two-dimensional echocardiography in 12 examinations (sensitivity, 80%; specificity, 97.4%). CONCLUSIONS: Our technique permits noninvasive evaluation of the size, stenoses, and atresia of the major portions of the PA branches in patients with cyanotic heart disease both before and after surgery.

Angiocardiography↗

PubMed1994

Ultrastructural localization of E-cadherin cell adhesion molecule on the cytoplasmic membrane of keratinocytes in vivo and in vitro.

We examined the ultrastructural localization of E (epithelial)-cadherin cell adhesion molecules by immunoperoxidase electron microscopy on the epithelium of mouse intestine, epidermis of human skin, and cultured human keratinocytes. The in vivo studies demonstrated that E-cadherin was present at the intermediate junction but not at the desmosome of the mouse intestinal single epithelium, and was found on the cytoplasmic membranes of keratinocytes with condensation in the intercellular space of the desmosomes, except for the basal surface of the basal cells. In vitro studies demonstrated that keratinocytes cultured in medium containing a low Ca2+ concentration (0.1 mM) lacked the tight connection through desmosomes, and that E-cadherin showed diffuse distribution and dot-like accumulation around the free surface of the cytoplasmic membrane. In culture medium containing a high concentration of Ca2+ (0.6 mM), keratinocytes formed desmosomal adhesion structures in which E-cadherin was accumulated. The free surface of the keratinocytes in this medium showed weaker distribution and a lesser amount of dot-like accumulation of E-cadherin than that in a low Ca2+ condition. These findings suggest that the distribution pattern of the E-cadherin cell adhesion molecules on the keratinocytes is different from that on the single epithelium of the intestine, and that E-cadherin on the cytoplasmic membrane of the keratinocytes shifts to the desmosomes under physiological conditions, participating in adhesion in association with other desmosomal cadherins.

Cadherins↗

PubMed1994

Monoclonal antibodies to a zinc-binding protein of rat Paneth cells.

Paneth cells are morphologically well characterized but their function has been not elucidated. Previously, we identified and purified a 90 KD zinc-binding protein (ZBPP-1) in rat intestine that was localized to Paneth cell granules, consistent with their high zinc content. To further elucidate the structure and function of ZBPP-1, we immunized Balb/c mice with purified ZBPP-1 and identified four independent monoclonal antibodies (MAb) producing MAb ZIP-1 (IgM), ZIP-2 (IgG1), ZIP-3 (IgM), and ZIP-4 (IgM). Immunohistochemistry (IHC) and immunoelectron microscopy (IEM) with these MAb showed positive staining of Paneth cell cytoplasmic granules. MAb ZBPP-1 also stained a population of mononuclear cells in the lamina propria of digestive tract mucosa and a few cells in spleen, presumably a subset of macrophages. These MAb will provide a useful tool to study the function of Paneth cells in human health and disease, since they cross-reacted with human intestinal Paneth cells and mucosal mononuclear cells.

Animals↗

PubMed1994

Regional blood flow distribution and left ventricular output during early neonatal life: a quantitative ultrasonographic assessment.

To examine the serial changes of left ventricular output and regional blood flow distribution during the early neonatal period, we measured blood flow volume in the ascending aorta, middle cerebral artery, celiac artery, superior mesenteric artery, and renal artery in 23 normal term infants at 1, 4-8, 24, and 96 h after birth. The blood flow volume in each vessel was measured by the pulsed Doppler technique. In the middle cerebral artery, celiac artery, and superior mesenteric artery, the blood flow volume at 1 and 4-8 h of age was significantly lower than after 24 h of age. In contrast, renal artery blood flow volume did not change significantly throughout the study period. The reduced organ blood flow volume soon after birth was related to a low diastolic blood flow in the major vessels, and the percent diastolic integral of blood flow velocity in each vessel showed an inverse linear correlation with the diameter of the ductus arteriosus. The left ventricular output 1 h after birth was 365 +/- 69 mL/kg/min, which was significantly higher than after 4-8 h of age. Left ventricular output gradually declined to 301 +/- 63 mL/kg/min at 4-8 h of age (p < 0.05 versus 96 h), 272 +/- 48 mL/kg/min at 24 h, and 258 +/- 54 mL/kg/min at 96 h. There was a significant positive correlation between left ventricular output and the ductus arteriosus diameter.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗

PubMed1994

[Effect of indomethacin as an adjunct to postoperative pain relief by continuous epidural infusion of bupivacaine and buprenorphine].

We examined the analgesic effects of indomethacin as an adjunct to postoperative epidural analgesia in 40 patients who underwent upper abdominal surgery. Twenty patients in control group were epidurally given 0.1 mg of buprenorphine in 8 ml of 0.25% bupivacaine immediately after surgery and subsequently infused 15 micrograms buprenorphine in 1 ml of 0.25% bupivacaine at a rate of 1 ml.h-1 for 48 h. The remaining 20 patients were rectally given 50 mg of indomethacin in addition to the same epidural method described above. The patients who did not need additional narcotics in the control and indomethacin groups were 45% and 80%, respectively (P < 0.05). In upper abdominal surgery, postoperative pain relief by epidural buprenorphine and bupivacaine plus rectal indomethacin was more effective than that by epidural buprenorphine and bupivacaine.

Abdomen↗

PubMed1994

Effect of dibutyryl cyclic AMP and interferon-gamma on Fc gamma receptor expression on eosinophils.

We studied the effect of dibutyryl cyclic adenosine-3',5'-monophosphate (dbcAMP) and several cytokines on the expression of IgG Fc receptor subclasses (Fc gamma RI, Fc gamma RII, and Fc gamma RIII) and low-affinity IgE Fc receptors (Fc epsilon RII/CD23) on peripheral eosinophils and on eosinophils differentiated in vitro from cord blood mononuclear cells by interleukin 5 (IL-5). These eosinophils expressed Fc gamma RII, and few, if any, Fc gamma RI and Fc gamma RIII as determined by flow cytometry with specific monoclonal antibodies. dbcAMP enhanced the Fc gamma RII expression, but did not induce the Fc gamma RI and Fc gamma RIII expression. Interferon-gamma (IFN-gamma) enhanced Fc gamma RII expression at the same degree as did dbcAMP. IFN-gamma also induced Fc gamma RIII expression on peripheral eosinophils but not on eosinophils grown in the presence of IL-5. Eosinophils grown in the presence of IL-5 showed a relatively immature phenotype, determined by electron microscopy and the low content of eosinophil cationic protein. Contrary to its enhancing effect on Fc gamma RII expression, dbcAMP suppressed the IFN-gamma-induced Fc gamma RIII expression on peripheral eosinophils. Other cytokines examined did not show any effects on Fc gamma R expression. Fc epsilon RII/CD23 expression was neither detected nor induced. These results indicate that expression of Fc gamma RII and Fc gamma RIII on eosinophils is regulated differently and that cAMP and IFN-gamma play important roles in the regulation of Fc gamma R expression.

Blood Proteins↗

PubMed1994

[Development of diagnostic method for liver disease].

Advance of current methods for management of liver diseases was discussed by eight discussers in this symposium. About three theme such as; 1. what laboratory parameters were helpful for prediction of effect of interferon (IFN) for HCV positive chronic hepatitis, 2. what tests were available for early diagnosis and prediction of prognosis in fulminant hepatitis, and 3. what laboratory parameters were useful for early diagnosis and prediction of development of hepatocellular carcinoma (HCC), hot discussion was performed. It was presented that time course of titration of HCV core antibody was available for prediction of effect of interferon in some cases. In patients with low concentration of HCV-RNA and genotype III, good effect of IFN was obtained. The possibility that the measurement of HCV serotype would become more common instead of that of HCV genotype because of its simplicity in methodology was presented. The measurements of plasma amino acids and human hepatocyte growth factor (h-HGF) were useful in early diagnosis of fulminant hepatitis. As current topics in management of HCC, the utility of determination of lectin affinity alpha-fetoprotein in early diagnosis of HCC, the importance of making definite diagnosis by target biopsy of HCC in early phase and prediction of development of HCC by abdominal sonogram were reported.

Carcinoma, Hepatocellular↗

PubMed1994

[Integrated diagnosis of small hepatocellular carcinoma with imaging diagnosis].

Herein, we present the diagnostic efficacy of various imaging diagnostic techniques for small liver cancer(HCC) and HCC occurrence predictability by ultrasonography during the follow-up period of chronic liver diseases. During the recent 4 years, 78 nodules of small liver cancer measuring 2 cm or less in diameter were found in 50 patients with liver cirrhosis. In this study, the tumor size was divided into 2 groups; 1.5 cm or less in maximal diameter (group A) and 1.6 to 2 cm (group B). The tumor detectability of ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), angiography and lipiodol CT in group A vs group B was 96% vs 97%, 68% vs 88%, 65% vs 94%, 12% vs 78% and 38% vs 89%, respectively. Therefore, angiography and lipiodol CT were not effective for detection of small HCCs smaller than 1.5 cm. Recently, helical CT scanning has been induced in the diagnosis of HCCs and the tumor detectability was enhanced to 82% even in group A. Additionally, helical-dynamic CT has some advantages in evaluating vascularity, especially arterial feeding which is a specific finding to HCCs. In comparison with contrast-enhanced US using CO2-microbubbles, helical-dynamic CT had equivalent accuracy in diagnosing hypervascular tumors, while hypovascular masses were observed in about 30% of group A. With respect to prediction of HCC occurrence in cirrhotic liver, sonographic evaluation of liver parenchyma seemed to be an important parameter.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1994

[Aggressive transformation of an indolent myeloma with abdominal extramedullary plasmacytoma after 6-year period of observation].

62-year-old female, who had been under observation for an indolent myeloma for six years without therapy, was admitted because of left flank pain. Various imaging modalities disclosed left pleural effusion, and a huge abdominal tumor involving the left crus of the diaphragm, spleen, stomach, pancreatic tail, left adrenal gland, left kidney and left posterior abdominal wall. Morphological and immunological examinations revealed extensive proliferation of more anaplastic myeloma cells within the tumor and in the pleural effusion than those in bone marrow on admission or at the beginning of the period of observation. Chemotherapy reduced serum M-protein, but LDH, the volume of the pleural effusion, and the size of the tumor increased. She died of pancreatitis associated with massive bleeding from the gastric tumor. Renal function was well preserved until her terminal phase. The clinical course showed the progression of indolent myeloma into an aggressive one without chemotherapeutic intervention, implying a rare subtype in terms of the natural history of multiple myeloma.

Abdominal Neoplasms↗

PubMed1994

[Recent advances in imaging diagnosis of pancreatic neoplasma with special reference to early diagnosis of the cancer].

Recent advance in various diagnostic imagings has enabled the early diagnosis of pancreatic tumors. In pancreatic cancer, the tumor-demonstrability by US, CT, and MRI has reached 80% in the recent 6 years, which is superior to the rate in the past decade from 1978 and 1987. However, the prognosis of pancreatic cancer is still poor even if the cancer can be resected. To improve the outcome of surgical intervention, early detection of small cancers (< or = 2 cm in diameter) and appropriate intervention based on preoperative diagnosis of the tumor extension are proposed. The tumor detectability of small pancreatic cancer by US, CT, MRI was 67%, 25%, 20%, respectively, and thus US was the most valuable tool. In the prediction of tumor extension of serosal invasion (S factor), retroperitoneal invasion (Rp factor) and vessel invasion (PV factor), both US and CT were efficacious with an accuracy of more than 70%. In conclusion, recently-advanced imaging seems to be useful for detecting a small pancreatic cancer and evaluating the tumor extension, but it remains difficult to diagnose a carcinoma in situ; a truly early cancer.

Adult↗

PubMed1993

Ultraviolet radiation abolishes cutaneous nerve stainings with two axon-specific antibodies in guinea-pig skin.

Cutaneous nerve fibers in guinea-pig skin were histochemically stained with two specific antibodies against different axonal proteins, a newly available protein gene product 9.5 and neuron-specific enolase. A semi-quantitative analysis revealed that the density of nerve fibers positive for either antibody was reversibly decreased following a single exposure to medium wave length ultraviolet (UVB) radiation and psoralen plus long wave ultraviolet (UVA) radiation (PUVA). UVA radiation alone did not markedly affect nerve fiber staining. The UVB/PUVA-induced nerve changes were augmented and prolonged following multiple exposures to UVB and PUVA. Nerve fiber staining was not altered by topical application of corticosteroids. Our findings suggest that both UVB and PUVA can alter the cutaneous innervation density.

Animals↗

PubMed1993

Lectin staining of the endothelial cell membrane is more sensitive to ultraviolet radiation than the epidermal cell staining in guinea-pig skin.

Ultraviolet radiation (UVR)-induced alterations in lectin stainings of both endothelial and epidermal cells were histochemically analysed in guinea-pig skin using Bandeiraea simplicifolia agglutinin-I and Ricinus communis agglutinin-I. The endothelial cell staining with both lectins was more sensitive to a single exposure to middle-wave UVR (UVB) and topical psoralen plus long-wave UVR (UVA) (PUVA) than the epidermal cell staining. More remarkable changes were seen following PUVA radiation than UVB radiation. No significant alterations were induced by UVA radiation alone or psoralen alone. The results suggest that the endothelial cell is a susceptible target for UVB and PUVA radiation.

Animals↗

PubMed1993

A case of nodular cutaneous amyloidosis. Amyloid production by infiltrating plasma cells.

We report a solitary nodular form of primary cutaneous amyloidosis due to locally infiltrating plasma cells. An 81-year-old Japanese women presented with a scarlet, dome-shaped 1.5-cm nodule with an irregular surface. Histology showed thick deposits of eosinophilic, oval, and homogeneous bodies in the dermis with mild infiltrates of mononuclear cells. The homogeneous bodies stained positively with periodic acid-Schiff, Congo red, and Yanagihara's Dylon stain, and immunohistochemically with anti-human lambda light-chain antibody. Methylgreen pyronine staining revealed that approximately half of the cellular infiltrates around the vessels were plasma cells. Electron microscopy demonstrated the homogeneous bodies to be amyloid masses, a part of which were in the cytoplasm of the plasma cells. Laboratory examination showed a slight elevation of IgG but no obvious findings suspicious for systemic amyloidosis or gammopathy.

Aged↗