Biomedical subjects

K Yamauchi

Publications and source records attributed to K Yamauchi.

At least 109 records · Page 6Linked to original sources

PubMed2000

Saliva level of free 3-methoxy-4-hydroxyphenylglycol (MHPG) as a biological index of anxiety disorders.

To access the saliva level of free 3-methoxy-4-hydroxyphenylglycol (MHPG) as a biological index of anxiety disorders, gender- or age-dependent changes in saliva MHPG level in patients with anxiety disorders were investigated. Saliva MHPG levels in 196 normal volunteers (59 male, 137 female) and 42 outpatients with anxiety disorders (20 male, 22 female) at the initial consultation to the hospital were measured by gas chromatography-mass spectrometry. Saliva MHPG levels in patients were higher than those in normal subjects. The increase in saliva MHPG levels in male patients was greater than that in female patients. Age-associated increase in the saliva MHPG level was greater in patients than in normal subjects. Especially, a significant interaction of age vs. patient effect was found in female subjects (P=0.0005), but not in male subjects (P=0. 174). These data indicate that the measurement of saliva MHPG would be valuable for detecting pathological anxiety in male patients regardless of age and in older female patients, but not in younger female patients.

Adjustment Disorders↗

PubMed2000

Genetic variants of IL-13 signalling and human asthma and atopy.

Asthma and atopy show epidemiological association and are biologically linked by T-helper type 2 (T(h)2) cytokine-driven inflammatory mechanisms. IL-4 operates through the IL-4 receptor (IL-4R, a heterodimer of IL-4Ralpha and either gammac or IL-13Ralpha1) and IL-13 operates through IL-13R (a heterodimer of IL-4Ralpha and IL-13Ralpha1) to promote IgE synthesis and IgE-based mucosal inflammation which typify atopy. Recent animal model data suggest that IL-13 is a central cytokine in promoting asthma, through the stimulation of bronchial epithelial mucus secretion and smooth muscle hyper-reactivity. We investigated the role of common genetic variants of IL-13 and IL-13Ralpha1 in human asthma, considering IgE levels. A novel variant of human IL-13, Gln110Arg, on chromosome 5q31, associated with asthma rather than IgE levels in case-control populations from Britain and Japan [peak odds ratio (OR) = 2.31, 95% CI 1.33-4.00]; the variant also predicted asthma and higher serum IL-13 levels in a general, Japanese paediatric population. Immunohistochemistry demonstrated that both subunits of IL-13R are prominently expressed in bronchial epithelium and smooth muscle from asthmatic subjects. Detailed molecular modelling analyses indicate that residue 110 of IL-13, the site of the charge-modifying variants Arg and Gln, is important in the internal constitution of the ligand and crucial in ligand-receptor interaction. A non-coding variant of IL-13Ralpha1, A1398G, on chromosome Xq13, associated primarily with high IgE levels (OR = 3. 38 in males, 1.10 in females) rather than asthma. Thus, certain variants of IL-13 signalling are likely to be important promoters of human asthma; detailed functional analysis of their actions is needed.

Adult↗

PubMed2000

Characterization of a testicular 17alpha, 20beta-dihydroxy-4-pregnen-3-one (a spermiation-inducing steroid in fish) receptor from a teleost, Japanese eel (Anguilla japonica).

A cDNA encoding a nuclear 17alpha,20beta-dihydroxy-4-pregnen-3-one (17alpha,20beta-DP, spermiation-inducing hormone in fish) receptor (DPR) was, for the first time, isolated from an eel testis cDNA library. The amino acid sequence of DPR shows high homology with those of human and chicken progesterone receptors. The affinity of the bacterial recombinant DPR ligand binding domain protein for 17alpha,20beta-DP is higher than that of progesterone. In transfection experiments using COS7 cells, the DPR showed progestin-dependent activation of transcription. 17alpha,20beta-DP was the most effective activator of transcription. These results indicate that the cDNA encodes a functional eel DPR, and show that 17alpha,20beta-DP has a nuclear receptor-mediated action in eel testes.

Anguilla↗

PubMed2000

Synthetic absorbable film for prevention of air leaks after stapled pulmonary resection.

Staple-line reinforcement buttresses made of bovine pericardium (BP), expanded polytetrafluoroethylene (ePTFE), and so on have been shown to be effective in preventing air leaks after stapled lung volume reduction operations, and some of them have been clinically utilized. However, each buttress suffers at least one disadvantage such as risk of viral infection and chronic inflammation. A new buttress was made using a poly(L-lactic acid-co-epsilon-caprolactone) film (L/C film) and its effectiveness as a staple-line reinforcement was examined by performing lung volume reduction operation on a canine model. Soft tissue responses to the buttress were compared with those to the BP strip and the absorbable behavior was studied. The L/C film buttress was flexible and thin enough to easily cut. Death of dogs, infection, acute and prolonged air leaks, and any complications related to its use were not observed. The tissue responses to the film were more mild and favorable than those to BP. The L/C film was absorbed after the staple line was covered by a connective tissue. The results described above suggest that the buttress made of an L/C film is a promising staple-line reinforcement material.

Absorption↗

PubMed2000

Analysis of hemoglobin and globin chain variants by a commonly used capillary isoelectric focusing method.

To analyze both hemoglobin (Hb) and globin chain variants, we modified a commonly used method, capillary isoelectric focusing (CIEF), with detection at 280 nm. The samples were hemolysates prepared from red blood cells, and globin chains obtained from the hemolysates by treatment with cold acidified acetone. When the migration time for the internal reference, carbonic anhydrase I (isoelectric point, pI 6.60), was taken as 1.0, the migration ratio for Hb A0 in normal human blood was 0.877 +/- 0.004 (mean +/- SD, n = 9), and those of the alpha- and beta-globin chains were 0.673 +/- 0.004 and 0.847 +/- 0.005 (mean +/- SD, n = 4), respectively. The ratio of peak heights between the beta- and alpha-globin chains (beta/alpha) in the normal Hbs obtained from four subjects was almost constant at 2.5 +/- 0.1 (mean +/- SD). This ratio indicates which of the globin chains includes a mutation (if one exists). When an Hb variant, Hb Hoshida (in which Gln is substituted for Glu at residue 43 in the beta-globin chain), was analyzed by this method, two main peaks were observed (migration ratios 0.836 and 0.877, corresponding to an abnormal and the normal Hb, respectively). An additional peak with an abnormal migration ratio of 0.788 was also detected in the globin chain profiles. The ratio of peak heights between normal beta- and alpha-globin chains was 1.57, indicating that a mutation exists in the beta-globin chain. We thus established a convenient system using CIEF that provides a rapid and reproducible method for the random analysis of both Hb and globin chain variants.

Electrophoresis, Capillary↗

PubMed2000

Molecular cloning and characterization of Japanese eel ovarian P450c17 (CYP17) cDNA.

As a first step in investigating the mechanism underlying the steroidogenic shift from the production of ovarian androgens (vitellogenic stage) to that of 17alpha-hydroxylated progestins (maturational stage) in Japanese eel during induced oogenesis, a cDNA encoding Japanese eel (Anguilla japonica) ovarian P450c17 (CYP17: steroid 17alpha-hydroxylase/C(17-20) lyase) was cloned and sequenced. This cDNA contained the complete coding region representing 510 amino acid residues, which showed high sequence homology to those of rainbow trout (74%) and mammals (45-55%). The protein encoded by this cDNA possessed high enzymatic activities of 17alpha-hydroxylase and C(17-20) lyase, thus quickly converting pregnenolone and progesterone to their respective delta(4) and delta(5) C19 products. P450c17 produced a single transcript of 2.4 kb in length, as assessed by Northern blot. Transcript levels of this enzyme significantly increased throughout artificially induced ovarian development. Considering this together with the previous data showing that C(17-20) lyase activity decreased from the vitellogenic to the maturational stage, whereas 17alpha-hydroxylase activity increased, the present data suggest that changes in C(17-20) lyase activity (the production of androgens) do not depend on transcriptional changes of the P450c17 gene.

Amino Acid Sequence↗

PubMed2000

Effect of diethylstilbestrol on thyroid hormone binding to amphibian transthyretins.

Transthyretin (TTR) is responsible for a major part of the binding of thyroid hormone to proteins in the plasma in amphibian tadpoles. To characterize the binding properties of amphibian TTRs, the effects of 17 hydrophobic signaling molecules, including 6 endocrine disruptors, on 3,5,3'-l-[(125)I]triiodothyronine ([(125)I]T(3)) binding to plasma proteins were examined in bullfrog Rana catesbeiana tadpoles. T(3) was the most potent competitive inhibitor among the 11 natural biological ligands studied, with an ID(50) of 8 nM. Diethylstilbestrol (DES) was the most powerful inhibitor among the 6 endocrine disruptors studied, with an ID(50) of 20 nM. Similar inhibitions of [(125)I]T(3) binding by these compounds were obtained when purified recombinant Xenopus and Rana TTRs were analyzed. Scatchard analysis revealed that Xenopus and Rana TTRs each possessed a single class of binding site for T(3), with a K(d) of 262 and 1.9 nM, respectively, at 0 degrees C. DES, at a concentration of 200 nM, induced the uptake of [(125)I]T(3) into Rana red blood cells suspended in Rana plasma from prometamorphic stages XIII-XV, when TTR is present in plasma. DES induced the uptake of [(125)I]T(3) into red blood cells to a lesser extent when they were suspended in Rana plasma from metamorphic climax stage XXIV, in which the level of TTR was lower than in plasma from the prometamorphic tadpoles. These results indicate that amphibian TTRs have the ability to bind DES with similar affinity to T(3), the natural ligand, and raise the possibility that DES binding to TTR might induce the temporary elevation of the free concentration of plasma T(3) followed by acceleration of cellular T(3) uptake.

Animals↗

PubMed2000

Effects of portal-systemic shunt following 90% partial hepatectomy in rats.

We studied the effects of portal-systemic shunt after massive hepatectomy. Male Wistar rats were divided into two groups: one group underwent laparotomy alone (C group) and in the other group a portal-systemic shunt was placed through laparotomy (S group). After 90% hepatectomy was performed, 3-day and 1-week survival rates and histopathology were examined, and hepatic hemodynamics during the early stage after hepatectomy were measured using dye-containing microspheres. The 3-day survival rate in the S group was significantly higher, and the 1-week survival rate was slightly higher, than those in C group. Sinusoidal dilation 7 days after hepatectomy in the S group was significantly milder than that in the C group. Fatty degeneration of hepatocytes in the S group was significantly milder than that in the C group. With respect to hepatic hemodynamics during the early stage after hepatectomy, the rate of shunt (26.3%) in the S group was significantly higher than that (9.5%) in the C group. Portal pressure, total hepatic blood flow, and total hepatic blood flow per gram of liver in the S group were significantly lower than those in the C group. These results suggest that approximately 26% shunt after 90% hepatectomy in rats increases the early survival rate and improves histological changes in surviving rats 7 days after resection.

Animals↗

PubMed2000

13-Week oral repeated administration toxicity study of bovine lactoferrin in rats.

Bovine lactoferrin (LF), which is an iron-binding glycoprotein in milk, was administered orally to groups of 12 males and 12 female rats at dose levels of 200, 600 and 2000mg/kg/day once daily for 13 weeks and its toxicity on repeated administration was examined. Throughout the administration period, there were no deaths caused by administration of the test compound, nor were there any adverse effects noted in the general condition of the animals. The study findings concerning body weight and food consumption, ophthalmology, urinalysis including water consumption, haematology, blood chemistry, necropsy, organ weights and histopathology revealed that there were no apparent changes due to administration of LF. Therefore, the level of LF at which no adverse effect was observed was considered to be 2000mg/kg/day for both sexes.

Administration, Oral↗

PubMed2000

Stability of transferred human chromosome fragments in cultured cells and in mice.

Chromosome fragments represent feasible gene delivery vectors with the use of microcell-mediated chromosome transfer. To test a prerequisite for a gene delivery vector, we examined the stability of human chromosome fragments (hCFs) in cultured cells and in trans-chromosomic (Tc) mice. Fragments of human chromosomes 2 (hCF(2-W23)), 11 (hCF-11) and 14 (hCF(SC20)) tagged with neo were introduced into the TT2F mouse ES cells, and retention of the hCFs was examined by FISH during long-term culture without selection. In contrast to the gradual loss of hCF(2-W23) and hCF-11, hCF(SC20) remained stable over 70 population doublings in the ES cells. The hCF(SC20) was also stable in cultured human tumor cells and chicken DT40 cells. We have previously generated chimeric mice using the ES cells harboring the hCF(2-W23) or hCF(SC20), followed by production of Tc mice. Although both the hCF(2-W23) and hCF(SC20) persisted in cells of Tc mice as an additional chromosome and were transmitted to offspring, the hCF(SC20) was more stable than the hCF(2-W23) in F1 and F2 mice. The present study shows that the stability of hCFs in Tc mice differs with tissue types and with genetic background used for successive breedings. Thus, the hCF(SC20), which was relatively stable in both mouse and human cells, may be a promising candidate for development as a gene delivery vector.

Animals↗

PubMed2000

Novel BCR-ABL transcript containing an intronic sequence insert in a patient with Philadelphia-positive acute lymphoblastic leukaemia.

In a patient with Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL), a novel variant of the chimaeric BCR-ABL mRNA transcript was detected by reverse transcription polymerase chain reaction (RT-PCR). Sequencing revealed the novel transcript to be a chimaeric mRNA produced by fusion of the BCR exon 14 (b3) to the ABL exon a2 with a 49-base pair (bp) insertion of an ABL intron 1b sequence between them. The insertion of the 49 bp introduced a stop codon. These data show that this variant of the chimaeric mRNA would not be translated into the p210 BCR-ABL protein. This could be one of the explanations as to why clinically the patient has responded well to therapy and continues to follow a mild clinical course.

Aged↗

PubMed2000

Oral administration of bovine lactoferrin for treatment of tinea pedis. A placebo-controlled, double-blind study.

A clinical study was conducted to evaluate the effectiveness of lactoferrin, which is a protein component of cow's milk, in the treatment of tinea pedis. Doses of either 600 mg or 2000 mg of lactoferrin, or a placebo was orally administered daily for 8 weeks to 37 adults who were judged to have mild or moderate tinea pedis. Dermatological improvement and antifungal efficacy were assessed. In the analysis of all subjects, dermatological symptoms scores in all groups decreased but the differences were not statistically significant comparing the three groups. However, in the analysis limited to subjects with moderate vesicular or interdigital tinea pedis, dermatological symptoms scores in the lactoferrin-treated groups decreased significantly in comparison with the placebo group (P < 0.05). The organisms isolated were Trichophyton rubrum and Trichophyton mentagrophytes. A mycological cure was not seen in any of the subjects. In the 37 subjects there were no adverse events and no subject withdrew from the study because of an adverse event. These results suggest that orally administered lactoferrin can improve the dermatological symptoms in some subjects. The potential usefulness of lactoferrin as a functional food material for treating tinea pedis was seen for the first time in this study.

Administration, Oral↗

PubMed2000

Two cases of persistent hyperinsulinemic hypoglycemia that showed spontaneous regression and maturation of the Langerhans islets.

Near-total pancreatectomy has been recommended as the treatment for persistent hyperinsulinemic hypoglycemia (PHH) in infants. However, recently there has been a report described that one third of 95% pancreatectomy failed to prevent hypoglycemia and more than two thirds had diabetes ultimately. The authors experienced 2 cases of PHH, which raise a query about the extensive pancreatectomy. Case 1: A female patient who manifested PHH shortly after birth underwent less extensive pancreatectomy twice at age 2 months and 8 years. After each operation, her clinical symptoms regressed, and she became free from the disease eventually. Histologic findings showed nesidioblastosis in which the islets clearly matured. Case 2: A male infant with PHH had an absolute indication for pancreatectomy. However, after a meticulous control of the blood glucose level with parenteral nutrition followed by continuous enteral nutrition feeding combined with medication, he became free from the disease. The current cases show there exist cases of PHH in which the islets mature and symptoms regress spontaneously. Therefore, we conclude near-total pancreatectomy is not always the treatment of choice. As an alternate strategy, long-term controlled feeding and medication combined with or without less extensive pancreatectomy should be considered with the expectation of spontaneous regression.

Adenoma, Islet Cell↗

PubMed2000

Surgical intervention for emphysematous pulmonary regions in a postoperative infant with congenital diaphragmatic hernia.

A postoperative infant with congenital diaphragmatic hernia (CDH) developed extrinsic obstruction of the trachea by the innominate artery that ensued from unequal expansion of the lungs followed by left mediastinal shift. Septation of the anterior mediastinum prevented unequal expansion of the lungs, and elongation of the innominate artery improved proximal airway obstruction. Prolonged artificial ventilation, however, resulted in the emphysematous bullae in the left lung. Lung volume reduction surgery (LVRS), at 3 years of age, ameliorated the respiratory distress and resulted in good weight gain. Surgical intervention, including LVRS, should be considered to improve respiratory disturbance caused by difference in compliance of the lungs in children.

Hernia, Diaphragmatic↗

PubMed2000

Endoscopic decompression procedure in acute obstructing colorectal cancer.

BACKGROUND AND STUDY AIMS: In the treatment of acute obstructing colorectal cancer, a nasoenteric ileus tube is not capable of providing sufficient decompression of the enlarged intestine immediately, and it may cause the patients throat pain. We therefore assessed the effectiveness of an endoscopic decompression procedure using a transanal ileus tube for acute obstructing colorectal cancer. PATIENTS AND METHODS: Five patients (five women, mean age 62) with colorectal cancer ileus underwent endoscopic decompression procedures between July 1994 and March 1999. The stricture was first negotiated using a guide wire 300 cm in length, and was then dilated using 8 Fr and 26 Fr dilating catheters. Immediately after a transanal ileus tube 120 cm in length with an outside diameter of 22 Fr was inserted, the intestinal tract was cleaned. RESULTS: No leakage from a colorectal anastomosis occurred during this endoscopic decompression procedure. Immediately after insertion of a decompression procedure tube, radical surgery could be performed after adequate preoperative examination and colorectal preparation. CONCLUSIONS: This procedure may be helpful in allowing immediate preoperative examination and scheduling of a radical operation for acute obstructing colorectal disease.

Acute Disease↗

PubMed2000

Changes in intestinal villi, cell area and intracellular autophagic vacuoles related to intestinal function in chickens.

1. Morphological changes in the intestinal villi, cell area and cell mitosis number in the duodenal epithelial cells were compared in cockerels fasted for 1, 2 and 3 d, and also when refed for 1 and 2 d after 3 d of fasting, to demonstrate whether these morphological changes are related to intestinal function. Alterations in the fine structure of vacuoles in epithelial cells were also examined in each group to investigate whether the vacuolar changes are associated with these morphological changes, and to obtain an index for judging the nutritional condition of the chicken intestine. 2. Fasting induced decreases in villus height, cell area and cell mitosis number, which recovered rapidly after refeeding, suggesting that these parameters are related to changes in intestinal function and may be useful for assessing intestinal function. 3. At 1 d of fasting, small electron-dense bodies appeared in the absorptive epithelial cells, some of them fusing with each other. As the fasting period increased, these small bodies developed to moderate-sized nascent autophagic vacuoles containing various kinds of electron-dense contents and finally became large autophagic vacuoles with electron-lucent contents. Some vacuoles showed positive acid phosphatase reactions, which indicated that they were lysosomal autophagic vacuoles containing hydrolytic enzymes. 4. After 1 d of refeeding the large autophagic vacuoles seen after 3 d fasting rapidly decreased to the small electron-dense bodies seen after 1 d of fasting. 5. These findings suggest that intestinal epithelial cells have the ability to digest their own cell components to supply nutrients during fasting by means of lysosomal active autophagic transport mechanisms: after refeeding, the epithelial cells return to the absorption of nutrients. 6. The present results demonstrate that the autophagic vacuolar changes are correlated with changes in intestinal villus height, cell area and cell mitosis number induced by fasting and refeeding; this indicates that autophagic vacuoles are a useful index of the nutritional condition of chicken intestine. The greater the number of electron-lucent vacuoles there are in the duodenal absorptive cells, the lower the nutritional condition of the chicken intestine.

Animals↗

PubMed2000

Amino acids dissolved in stream water as possible home stream odorants for masu salmon.

It is well established that salmon return to their home stream by sensing the odors of the stream water. In this study we have attempted to identify the home stream odorants used by masu salmon in Lake Toya. The salmon in Lake Toya return to the home stream which flows into the lake after lake life for 2-3 years. Besides water from the home stream, waters from two other streams which flow into Lake Toya were also used in the experiments. We analyzed the compositions of amino acids, inorganic cations and bile acids in waters from the three streams. Application of mixtures of inorganic cations or bile acids, reconstituted based on the compositions of the stream waters, to the olfactory epithelium induced only very small responses. On the other hand, application of mixtures of amino acids induced large responses. The response to artificial stream water reconstituted based on the compositions of amino acids and salts closely resembles that to the corresponding stream water. Cross-adaptation experiments with three combinations of the mixtures were carried out. The response pattern for each combination closely resembled that to the corresponding combination of stream waters. Based on the results obtained, we concluded that amino acids dissolved in the home stream water are possible home stream odorants.

Amino Acids↗

PubMed2000

Lactoferrin given in food facilitates dermatophytosis cure in guinea pig models.

Dermatophytosis is the most common skin infection caused by dermatophytic fungi, such as Trichophyton spp. We studied the in vitro and in vivo antifungal effects of lactoferrin against Trichophyton. Human and bovine lactoferrin, and a bovine lactoferrin-derived peptide, lactoferricin B, showed in vitro antifungal activity that was dependent on the test strain and medium used. In guinea pigs infected on the back with Trichophyton mentagrophytes (i.e. those with tinea corporis), consecutive daily po administration of bovine lactoferrin did not prevent development of symptoms during the early phase of infection, but facilitated clinical improvement of skin lesions after the peak of the symptoms. The fungal burden in lesions was less in guinea pigs that had been given lactoferrin than in untreated controls 21 days after infection. In guinea pigs infected on the foot with T. mentagrophytes (i.e. those with tinea pedis), the fungal burden of the skin on the heel portion of the infected foot 35 days after infection was lower in animals fed lactoferrin than in controls. These results suggest the potential usefulness of lactoferrin as a food component for promoting dermatophytosis cure.

Administration, Oral↗