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Biomedical subjects

M Manabe

Publications and source records attributed to M Manabe.

At least 19 recordsLinked to original sources
PubMed1999

Architectural organization of filiform papillae in normal and black hairy tongue epithelium: dissection of differentiation pathways in a complex human epithelium according to their patterns of keratin expression.

BACKGROUND: An inadequate understanding of the complex morphologic characteristics of human filiform papillae has hampered the histopathological characterization of disorders affecting tongue keratinization. To better define the 3-dimensional cytoarchitecture of tongue epithelium, we performed detailed immunohistochemical analyses of normal and black hairy tongue tissues using a panel of antikeratin antibodies. OBSERVATIONS: The dome-shaped base of the human filiform papilla (primary papilla) is surmounted by 3 to 8 elongated structures (secondary papillae). These secondary papillae are composed of a central column of epithelial cells expressing hair-type keratins and an outer rim of cells expressing skin-type keratins. The epithelium overlying the primary papillae and between the individual primary papillae express esophageal-type keratins. In black hairy tongue disease, there is a marked retention of secondary papillary cells expressing hair-type keratins. CONCLUSIONS: Using a panel of antikeratin probes, we define the precise topographical localization of cell populations undergoing 3 distinct differentiation programs in dorsal tongue epithelium. Comparative analyses of black hairy tongue specimens indicate that defective desquamation of the cells in the central column of filiform papillae results in the formation of highly elongated, cornified spines or, "hairs"--the hallmark of this disease.

Antibodies↗
PubMed1998

Insulin-induced hypoglycemia elicits thymocyte apoptosis in the rat.

Although various types of stress induce thymus atrophy and suppress immune functions, the mechanisms involved are unknown. To test the hypothesis that thymocyte apoptosis plays a role in stress-induced atrophy of the thymus, we studied the effects of starvation and hypoglycemia on the thymus in the rat. Administration of insulin caused marked hypoglycemia, increased the plasma corticosterone level, and induced fragmentation of thymocyte DNA in fasted but not in fed rats. Administration of either glucose or RU486, a glucocorticoid receptor antagonist, inhibited the apoptosis of thymocytes elicited by insulin. Available evidence suggest that insulin-induced hypoglycemia causes thymocyte apoptosis by promoting glucocorticoid secretion from the adrenal gland.

Adrenalectomy↗
PubMed1998

Esophageal strictures in children with recessive dystrophic epidermolysis bullosa: experience of balloon dilatation in nine cases.

BACKGROUND: Recessive dystrophic epidermolysis bullosa is a rare disorder characterized by extreme vulnerability of the squamous epithelium and mucous membranes. Minor trauma such as is caused by swallowing solid food is followed by blistering and scarring. Stricture formation at the pharyngoesophageal junction (C6 or C7) is the severest complication of this disease. METHODS: We evaluate the effectiveness of Microvasive Rigiflex balloon dilatation and extensive nutritional support as a primary treatment for this condition. Nine of 21 recessive dystrophic epidermolysis bullosa patients developed esophageal strictures at the level of the pharyngo-esophageal junction (C6). We treated them with intensive nutritional therapy followed by balloon dilatation, which produces longitudinal pressure and provides prompt relief from esophageal stricture. Eleven balloon dilatations have been performed in 9 patients. RESULTS: All patients had poor physical development and were severely malnourished; extensive nutritional support was required before treatment could begin. Balloon dilatation was performed once in seven patients and twice in two patients. No recurrent stricture formation was observed after balloon dilatation. CONCLUSION: Intensive nutritional support followed by balloon dilatation is the first choice of treatment for esophageal strictures complicating recessive epidermolysis bullosa. By following this regime, invasive surgery can be avoided.

Adolescent↗
PubMed1998

In vitro study on antioxidant potential of various drugs used in the perioperative period.

BACKGROUND: Since surgical trauma not only intensifies the oxidative stress by generating reactive oxygen species (ROS), but also weakens the biological defense system against ROS attack, the antioxidant activity of drugs used during the perioperative period, which possibly normalizes the impaired redox state in the patient, is of fundamental importance and great clinical interest. METHODS: We have applied the phycoerythrin fluorescence-based assay, in which 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)-generated peroxyl radical attacks B-phycoerythrin (B-PE) to lead to a sensitive decrease in its fluorescence intensity linearly, to evaluate the antioxidant activity of major drugs in anesthetic practice. RESULTS: By the protective effect on B-PE fluorescence decay, the antioxidant activities of the drugs were classified into three groups: Group I drugs, which only slowed B-PE fluorescence decay (nicardipine, verapamil, diltiazem, ephedrine, aminophylline, vecuronium, lidocaine, mepivacaine, midazolam, thiamylal, droperidol, ketamine, hydroxyzine, butorphanol, prednisolone, hydrocortisone, betamethasone, dexamethasone, methylprednisolone, and furosemide); Group II drugs, which protected B-PE oxidation completely and stopped fluorescence decay in a certain duration (dopamine, epinephrine, norepinephrine, dobutamine, isoproterenol, and buprenorphine); and Group III drugs, which had no protective effect on B-PE oxidation (nitroglycerin, prostaglandin E1, neostigmine, pancuronium, suxamethonium, atropine, bupivacaine, pentazocine, and heparin). CONCLUSION: These results indicate that Group I and II drugs exert some antioxidant activity in vitro, as measured by their protection of fluorescence decay of B-PE. Careful consideration of these properties might, then, serve to facilitate more efficient drug application.

Adjuvants, Anesthesia↗
PubMed1998

Blood pressure control during eye surgery under local anesthesia using pulse oximetry.

We measured the arterial blood pressure and percutaneous O2 saturation (SpO2) in 39 elderly patients (age range, 70-89 years) who underwent cataract surgery under local anesthesia. Nineteen patients showed a 20% or greater increase in the systolic arterial pressure (SAP) measured every minute in the operating room compared to the basal value measured in the ward. We treated elevation of the SAP by intravenous bolus injection of 0.25 mg nitroglycerin (NTG), followed by continuous infusion at 0.1-0.3 microg/kg/min. NTG caused a statistically significant but clinically irrelevant decrease in SpO2 in the patients breathing room air. Two of these patients showed extremely decreased SpO2. Our results suggest that NTG does not typically cause a severe decrease in oxygenation. It might be advisable, however, for patients with severe lung dysfunction or ischemic heart disease to receive prophylactic O2 administration.

Aged↗
PubMed1998

Apo A-I and apo E concentrations in cerebrospinal fluids of patients with acute meningitis.

It has been demonstrated that apolipoproteins found in cerebrospinal fluid (CSF) play an important role in lipid metabolism in the central nervous system (CNS). Previously we reported that CSF apo A-I levels increased with the severity of neurological damage in poliovirus-infected macaques. In the present study, apo A-I was quantitatively analysed in CSF from patients with or without neurological diseases. In controls, CSF apo A-I level was significantly higher in males; 3.83 (0.40) mg/L, mean (SEM) (n = 19) compared with females, 2.42 (0.26) mg/L (n = 23, P < 0.05). CSF apo A-I concentrations in patients with acute meningitis increased at the active stage, 7.74 (1.78) mg/L (n = 10), but returned to basal concentrations at the convalescent stage 2.72 (0.38) mg/L (n = 10), while the CSF apo A-I level in patients with other neurological diseases remained in the same range as in controls. By contrast, CSF apo E was consistently elevated at either stage of acute meningitis. Furthermore, it was found that the levels of CSF apo A-I, but not of apo E, correlated positively with CSF albumin concentrations. These findings suggest that the CSF apo A-I and apo E have different origins and may play different roles in the lipoprotein metabolism in CNS.

Acute Disease↗
PubMed1998

Serum lipoprotein lipase in healthy subjects: effects of gender and age, and relationships to lipid parameters.

Using serum samples obtained from normal individuals who had not received heparin injection, we investigated the relationship of lipoprotein lipase (LPL) to lipid and apolipoprotein concentrations in serum. For the measurement of LPL concentration, a highly sensitive enzyme-linked immunosorbent assay (ELISA) was developed, in which the lowest detection limit was 9 micrograms/L. The mean (SD) serum LPL concentration was 50.7 (14.9) micrograms/L (n = 240). It was lower in men [45.5 (14.0) micrograms/L in men and 56.0 (13.9) micrograms/L in women]. Serum LPL concentration correlated positively with high-density lipoprotein cholesterol (HDL-C, r = 0.549) and apolipoprotein AI (apoAI, r = 0.487), and inversely with triglycerides (r = -0.423). Our results suggest that serum LPL may be a factor in the modulation of HDL-C and triglyceride concentrations in normal subjects.

Adult↗
PubMed1998

Deimination of 70-kD nuclear protein during epidermal apoptotic events in vitro.

Peptidylarginine deiminase (PAD) is the enzyme responsible for converting protein-bound arginine residues to citrulline. It has recently been shown that a number of epidermal proteins, including filaggrin, trichohyalin, and keratins, are deiminated by the action of PAD, suggesting a possible role for protein deimination during the final stages of epidermal differentiation. We report here a novel PAD substrate found during the course of identifying deiminated proteins in cultured rat epidermal keratinocytes. We found that a 70-kD protein localized to the periphery of the nucleus was preferentially deiminated after ionomycin treatment in the presence of 2 mM calcium and was associated with apoptotic events in these cells. Furthermore, we discovered that the deimination of nuclear protein could be induced by transfection of a PAD cDNA into rat epidermal keratinocytes. These data suggest that PAD may act on the 70-kD nuclear protein to induce disassembly of the nuclear lamina and promote apoptosis during terminal epidermal differentiation.

Animals↗
PubMed1998

[A case of pheochromocytoma incorrectly diagnosed before and during surgery].

In a patient with an adrenal tumor, although norepinephrine levels in the blood and urine were abnormally high, findings in CT and 131 I-MIBG scintigraphy denied pheochromocytoma. The preoperative diagnosis was metastatic adrenal tumor. The surgical manipulation of the tumor increased the blood pressure from 110/60 to 210/110 mmHg. However, intraoperative microscopic examination in frozen section excluded again possibility of pheochromocytoma. Later, findings in the permanent specimen confirmed that the tumor was pheochromocytoma. The problem of this case was that each specialist made judgment only on the subject of his own interest without considering of the patient's status as a whole. Anesthesiologist should have the ability to make preoperative assessment of a patient by using all available information with his unbiased mind.

Adrenal Gland Neoplasms↗
PubMed1998

[The relationship between respiratory function and the change in end-tidal nitrous oxide concentration].

The aim of the present study is to clarify the relationship between respiratory function and the rate of change in alveolar anesthetic concentration. We measured the concentration of end-tidal nitrous oxide (N2O) when 50% N2O was administered to 15 patients of ASA I possessing normal respiratory function during the course of propofol-100% oxygen anesthesia. All patients were ventilated at a rate of 8-10 ml.kg-1 x 8 times per minute using a conventional anesthetic ventilator with semi-closed circuit and 4 l.min-1 inflow of fresh gas. Arterial CO2 partial pressure was maintained at 36.2 +/- 1.8 mmHg and no significant circulatory change was observed while N2O was administered. The rate of increase of end-tidal N2O concentration in poor FEV1.0/FVC% group was significantly slower than that in high FEV1.0/FVC% group, while there was no relation between %VC and the end-tidal N2O concentration change. Since N2O is an inhaled anesthetic, it is well considered that the effect of FEV1.0/FVC% may be observed in other inhaled anesthetic although the magnitude of the effect may vary. The present result suggests that respiratory function, especially FEV1.0/FVC%, is an important factor affecting the rate of change in alveolar anesthetic concentration and, in lower FEV1.0/FVC% group, it takes more time to achieve the intended alveolar concentration.

Aged↗
PubMed1997

Osseointegration of dental implants in rabbit bone with low mineral density.

PURPOSE: The purposes of this study were to establish an experimental animal model with bone of low mineral density, and to then investigate the reaction of the bone-implant interface in these experimental animals. MATERIALS AND METHODS: To prepare the experimental model, rabbits were ovariectomized and fed a 0.15% low-calcium diet. The bone mineral density (BMD) of the tibia was periodically measured by dual-energy X-ray absorptiometry. Approximately 1 month after the introduction of the low-calcium diet, when BMD had decreased to about 12% less than that of control rabbits, a titanium implant (TI) was inserted into the tibia of each rabbit. At 2, 4, 8, and 12 weeks after the insertion of the TI, the rabbits were killed, and the reaction of the bone tissue surrounding the TI was examined both histologically and radiographically. RESULTS: The combined ovariectomy and low-calcium diet produced rabbits having bone with low mineral density, and the histologic features of the tibia in these rabbits were consistent with those in human osteoporotic bone. In control rabbits, new bone formation surrounding the TI was evident 2 weeks after its insertion, and the TI surface was almost completely covered with new bone after 8 weeks. In contrast, new bone formation in the experimental rabbits was delayed, but considerable direct bone contact with the TI was observed after 12 weeks. CONCLUSION: These results suggest that osteoporotic bone may affect the healing period of bone tissue after the insertion of dental implants, but that osseointegration of dental implants may be obtained even in osteoporotic bone.

Animals↗
PubMed1997

Greater incidence of delirium during recovery from sevoflurane anesthesia in preschool boys.

BACKGROUND: In the authors' clinical experience, preschool children are more likely to show delirium after sevoflurane than are older children. METHODS: Sixty-three preschool boys aged 3-5 yr (classified as American Society of Anesthesiologists [ASA] physical status I), and 53 school-age boys aged 6-10 yr (ASA physical status I) who underwent minor urologic surgery were randomly assigned to receive either halothane or sevoflurane, thus creating four groups: preschool-halothane (n = 32), preschool-sevoflurane (n = 31), school-halothane (n = 27), and school-sevoflurane (n = 26). Anesthesia was induced by inhalation of halothane or sevoflurane in oxygen and was maintained at 1 minimum alveolar concentration of each agent throughout surgery. For intra- and postoperative analgesia, caudal block with 0.5-1.0 ml/kg 0.25% plain bupivacaine and topical infiltration with 3-5 ml 1% lidocaine were provided for all patients. Recovery characteristics and incidence of delirium on emergence were compared among the four groups. RESULTS: Two patients in the preschool-halothane group, one in the preschool-sevoflurane group, and one in the school-halothane group were excluded from the comparison because of insufficient analgesia or agitation before induction. In both age groups, the time to emergence from sevoflurane was significantly faster (about 3 min) than from halothane. The incidence of delirium during recovery in the preschool-sevoflurane group (40%) was significantly greater than that in the other groups (preschool-halothane, 10%; school-halothane, 15.4%; school-sevoflurane, 11.5%). CONCLUSION: Sevoflurane provided quicker emergence and early recovery compared with halothane, but the incidence of delirium was greater in preschool boys after sevoflurane.

Age Factors↗
PubMed1997

Differences in hormonal responses to preoperative emotional stress between preschool and school children.

BACKGROUND: The behavior of children under emotional stress differs according to whether they are of preschool or school age. METHODS: To examine the effect of age on hormonal responses to preoperative emotional stress, we measured the concentrations of catecholamines (adrenaline and noradrenaline) and cortisol in 56 healthy boys before surgery. RESULTS: Among preschool boys (3-5 years old), those showing anxious behavior showed significantly higher cortisol, adrenaline, and noradrenaline concentrations in the blood circulation than those not showing such behavior (P < 0.0001, P < 0.0001 and P < 0.005, respectively). However, among the schoolboys (6-11 years old), anxiety was associated only with the cortisol concentration (P < 0.01). CONCLUSION: Hormonal responses to preoperative emotional stress in preschool boys differ from those in schoolboys.

Age Factors↗
PubMed1997

[Determination of malondialdehyde-modified LDL(MDA-LDL) and its potential usefulness].

Numerous studies have indicated that oxidative modification of low-density lipoprotein(LDL) plays a critical role in the pathogenesis of atherosclerosis. Malondialdehyde-modified LDL(MDA-LDL) is one of the candidates which is the oxidative product of LDL. However, the existence of MDA-LDL in the circulation has been in dispute. Therefore, for the assessment of oxidized-LDL in human serum, we developed a sensitive enzyme-linked-immunosorbent assay(ELISA) for the detection of MDA-LDL. In our method, monoclonal antibody against MDA-LDL, ML25 was used. ML25 recognized MDA-LDL as well as MDA-modified proteins by a solid-phase competitive enzyme immunoassay. Therefore, to establish an ELISA method which is specific for detection of MDA-LDL, ML25 was combined with apoB-specific antibody (AB16) as the second antibody. Using this method, MDA-LDL was detectable in the sera of 314 healthy individuals. The concentration of MDA-LDL preferably ranged from 20 to 80 units/l when the absorbance with artificially prepared MDA-LDL at the concentration of 1 mg/l was defined as 1 unit/l. Furthermore, assays for lipoprotein subfractions separated by density-gradient ultracentrifugation revealed that MDA-LDL was mainly distributed in the LDL fraction as expected, and MDA-LDL/apoB ratio showed a peak at small, dense LDL fractions. This finding seems to be quite interesting since an elevated level of small, dense LDL has been reported to be associated with an increased risk of atherosclerosis. We concluded that our method is useful for specific detection of MDA-LDL in human serum and might be an elevation method for atherogenicity.

Arteriosclerosis↗
PubMed1997

[Complete cholesteryl ester transfer protein deficiency increases oxidized-LDL in plasma].

Malondialdehyde-modified LDL(MDA-LDL) is one of the major oxidative LDL. MDA-LDL was determined by enzyme immunoassay in patients with complete and partial cholesteryl ester transfer protein(CETP) deficiency. Significantly increased serum MDA-LDL levels and MDA-LDL/apoB ratios in the LDL fraction were observed in patients with complete CETP deficiency but not for those with partial CETP deficiency. The present results may indicate that patients with complete CETP deficiency have a higher risk for atherosclerosis than those with partial CETP deficiency and normal.

Arteriosclerosis↗
PubMed1997

[Effect of controlled hypotension on cerebral oxygen delivery].

The margin of safety for controlled hypotension is still unclear especially in the central nervous system (CNS) which is one of the most sensitive organs to hypoxia and ischemia. Recently, cerebral optical spectroscopy in the infrared light range was developed as a useful tool which makes it possible to monitor cerebral oxygenation (rSO2) non-invasively and continuously during anesthesia. Resulting rSO2 mainly reflects oxygen extracts by cerebral tissue and then indicates cerebral oxygen delivery. We examined the limitation of controlled hypotension in the brain in 12 patients by monitoring rSO2 during anesthesia. rSO2 under room air breathing (control value as normal physiological condition) was 67 +/- 3% (mean +/- SEM). It significantly increased by 5.6 +/- 0.8% under 100% oxygen breathing, but decreased near to the control value under sevoflurane anesthesia (FIO2 1.0). During moderate controlled hypotension (70% of normal blood pressure) by prostaglandin E1 under sevoflurane anesthesia (FIO2 1.0). rSO2 remained at control value, indicating that cerebral oxygen delivery was still sufficiently maintained. However rSO2 decreased significantly by 9.0 +/- 1.1% in same controlled hypotension condition under FIO2 0.4. This decrease in rSO2 could be potentially harmful for CNS although any post-operative neurological disorder was not observed in our cases. We conclude that cerebral oxygen delivery may be insufficient even in the moderate controlled hypotension, and thus higher FIO2 is recommended in such procedures.

Alprostadil↗
PubMed1997

Distinctive expression of filaggrin and trichohyalin during various pathways of epithelial differentiation.

Filaggrin and trichohyalin are keratin intermediate filament-associated proteins, and are primarily expressed in the granular cells of the epidermis and in the inner root sheath cells of the hair follicles, respectively. These two proteins are, however, occasionally co-expressed in some tissues. To gain more insights into the mechanisms for expression and processing of (pro)filaggrin and trichohyalin during various pathways of epithelial differentiation, we compared their localization by double immunostaining techniques in normal and psoriatic epidermis, tongue filiform papillae and cultured human epidermal keratinocytes. In normal foreskin, trichohyalin immunoreactive cells were observed only occasionally and, when present, they always co-expressed filaggrin. Trichohyalin expression occurred, however, in filaggrin-negative cells as well as in filaggrin-positive cells in the psoriatic epidermis, tongue papillae and cultured keratinocytes. Filaggrin and trichohyalin were induced independently at different times following calcium shift in cultured keratinocytes. Immunoelectron microscopy demonstrated the distinct intracellular distribution of filaggrin and trichohyalin. Some filaggrin granules were observed in the cells where trichohyalin was diffusely distributed. Likewise some trichohyalin granules were found in the cells with diffuse filaggrin labelling. These results suggest the existence of distinct expression/processing mechanisms of filaggrin and trichohyalin in differentiating keratinocytes.

Adult↗