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Biomedical subjects

M Yamauchi

Publications and source records attributed to M Yamauchi.

At least 271 records · Page 15Linked to original sources

Urinary level of L-fucose as a marker of alcoholic liver disease.

The urinary levels of L-fucose were measured in 93 alcoholics; 20 of these were without liver disease, 57 with noncirrhotic alcoholic liver disease, and 16 with alcoholic liver cirrhosis. In addition, patients with cirrhosis due to viral infection, and healthy subjects were evaluated. The mean urinary L-fucose concentration showed significantly higher values in patients with alcoholic liver disease and alcoholic liver cirrhosis when compared with the healthy subjects or the chronic alcoholics without liver disease (p < 0.001). The urinary L-fucose level was also significantly higher (p < 0.001) in cases of alcoholic liver cirrhosis than in noncirrhotic alcoholic liver disease (384 +/- 97 vs. 240 +/- 95 mumol/g of creatinine). No difference was observed between the healthy subjects and chronic alcoholics without liver disease (143 +/- 29 vs. 155 +/- 60 mumol/g of creatinine). The urinary level of L-fucose was significantly higher with alcoholic cirrhosis (384 +/- 97 mumol/g of creatinine) than with viral cirrhosis (265 +/- 42 mumol/g of creatinine) (p < 0.001). The measurement of urinary L-fucose may be a useful marker of alcoholic liver disease.

Adult↗

Prenatal diagnosis of a hypermethylated full fragile X mutation in chorionic villi of a male fetus.

Fragile X syndrome, one of the most common human genetic diseases, is characterised by a unique genetic mechanism which involves dynamic mutation because of a heritable unstable DNA sequence and abnormal DNA methylation. Direct detection of the dynamic mutation and its methylation status at the DNA level would facilitate reliable tests for prenatal and postnatal diagnosis of the disease and for carrier detection. However, it has been suggested that DNA methylation can not be used as the basis for prenatal diagnosis as the CpG island is not always methylated in chorionic villus DNA. We report here a male fetus exhibiting both extensive somatic heterogeneity and abnormal hypermethylation of the full fragile X mutation in chorionic villus DNA as well as in fetal tissue DNA. Our results indicate that both somatic heterogeneity and hypermethylation of the full fragile X mutation are events that are clearly detectable in the 11th to 12th week of pregnancy.

Blotting, Southern↗

Changes in plasma androgen levels and testicular histology with descent of the testis in the dog.

Levels of 4-androstenedione (A), 5 alpha-dihydrotestosterone (DHT) and testosterone (T) in plasma collected from the heart or the jugular vein were measured in 61 male fetal dogs at between 38 and 60 days of gestation and 55 male neonatal dogs at between 0 and 50 days after birth. Testicular descent and histology were investigated after euthanasia of the fetuses and neonates. Although the testis still lay on the caudal ridge of the kidney in the 38- and 40-day-old fetuses, the gonad had slightly migrated from the kidney by 42 days of gestation. The testis approached the internal inguinal ring at Day 0 after birth and had passed through the inguinal canal at Day 5 after birth. The inguinal passage was the active phase of testicular descent. Both testes were drawn into the scrotum after 35 days of age. The number of gonocytes in the seminiferous cords had increased in the 58-day-old fetus, and Leydig cells in the stroma had become obvious because of morphological development and the formation of cell clumps. Plasma A levels in the male fetuses decreased temporarily after birth and plasma DHT increased provisionally at 54 and 58 days of gestation. Plasma T levels in the male neonates increased markedly after birth. These findings suggest that testicular descent in the dog fetus is accelerated by the DHT and T secretory function of the Leydig cells which increased after 54 days of gestation.

Aging↗

Information-processing mediating the location-distance interference in motor short-term memory.

We reviewed the literature on basic psychological correlates of the well-known phenomenon of the location-distance interference in motor short-term memory (Kerr, 1978; Walsh, Russell, Imanaka, & James, 1979). The location-distance interference in motor short-term memory has frequently been demonstrated as an unavoidable interference phenomenon observed in the reproduction of movement location and distance in arm positioning. The most important aspect of this phenomenon is that even when a subject concentrates on a specific cue (i.e., either end-location or distance) the other cue is also coded unintentionally and, as a result, the reproduction movement guided on the basis of the specific cue is unavoidably influenced by the other nonspecific cue. In this review article, we first reviewed the literature on the basic theories and nature of short-term memory, particularly on the limited processing capacity. We then referred to the unlimited, automatic processing in visual-verbal domains, referring to the Stroop phenomenon. Finally, in conjunction with the notion of automatic processing, we examined the possible aspects of information processing which may be responsible for mediating the location-distance interference in motor short-term memory.

Cues↗

A diabetic case of Hb Riyadh with a low HbA1c value.

A 74-year-old male patient with diabetes mellitus and hypertension who had been treated for a long period was admitted to our hospital. Laboratory data on admission revealed high values for fasting blood sugar and fructosamine, 219 mg/dl and 389 mumol/l respectively, while the concentration of glycated hemoglobin (HbA1c) was low (3.0%). High performance liquid chromatography and isoelectric focusing analysis of the patient's Hb disclosed abnormal Hb with the content being 41.3%. The structural analysis indicated that this abnormal Hb was Hb Riyadh [beta 120 (GH3) Lys-->Asn]. The low value of HbA1c despite the high blood glucose level may be attributed to this abnormal hemoglobin.

Aged↗

The post-translational chemistry and molecular packing of mineralizing tendon collagens.

Using cross-linking stereochemistry as indicators, the molecular environment of two collagens in the turkey leg Achilles tendon were compared. The tendon from one year old turkeys was dissected into nonmineralized, fully mineralized and transitionally mineralized portions. Amino acid composition and cyanogen bromide peptide mapping of these portions indicated that the collagens were essentially type I throughout. The fully mineralized compartment had a lysine hydroxylation level similar to turkey or mammalian bone collagen. The non- and transitionally mineralized collagens had a significantly higher lysine hydroxylation, typical of tendon or ligament. However, unlike mammalian tendon, the collagen cross-links were essentially derived from the carboxy-terminal ends of the molecules. The predominant cross-link in this portion was pyridinoline having a high content of 0.95 +/- 0.09 res/mole of collagen. The cross-links in the fully mineralized collagen were also essentially derived from carboxy-terminal aldehyde. However, here significant amounts of the lysyl analog of pyridinoline and lysine-involved bifunctional cross-links were present. The molecular loci of pyridinoline in nonmineralized collagen and the lysyl analog of pyridinoline in mineralized collagen were found to be identical. The total trifunctional cross-link level in the mineralized collagen, 0.55 +/- 0.05 res/mole of collagen, was virtually identical to that observed in old mammalian bone and dentin, and in long term in vitro incubation studies of predentin. We have tentatively concluded that the post-translational chemistry and molecular environments are different in these two turkey tendon fibrils. However, a relative paucity of amino-terminal based cross-links is a feature they have in common. The possible involvement of the amino-terminal telopeptides in collagen mineralization is discussed.

Amino Acids↗

Tendon collagens: extracellular matrix composition in shear stress and tensile components of flexor tendons.

Outer synovial tissues were separated from the remainder of avian flexor tendon and the collagens characterized biochemically and compared with those of the internal portion of tendon and sheath. The collagen content of tendon synovium was 23%, whereas that of tendon and sheath were 78% and 73%, respectively, based on dry weight. Four genetic types of collagen were found in the pepsin solubilized matrices: in the synovium, types I (78%) and III (19%) predominated; types V and possibly VI were present as minor collagens. Purified synovial type V collagen was a heterotrimer, with chain composition [alpha 1(V)]2 alpha 2(V). In contrast, the internal portion of tendon and sheath were comprised of only type I collagen. There was a large amount (41%) of ethanol extractable, noncollagenous material present in synovium, a part of which was proteoglycans. In addition, collagen cross-links of these tissues were quantified: the internal tendon had an abundant concentration of pyridinoline; synovium exhibited high amounts of labile, reducible cross-links, particularly dihydroxylysinonorleucine. In the case of sheath, lysine aldehyde-derived cross-links appeared to be predominant. These results indicate that each tissue has its own collagen type distribution as well as cross-linking pattern reflecting their maturational and functional differences.

Animals↗

Prevalence of hepatocellular carcinoma in patients with alcoholic cirrhosis and prior exposure to hepatitis C.

Sixty-three patients with alcoholic cirrhosis were retrospectively studied for the prevalence of antibodies to core (P22) and nonstructural (C100) region of hepatitis C virus (HCV). The prevalence rate of anti-P22 antibodies in patients with alcoholic cirrhosis was higher than that of anti-C100 antibodies (63.5% vs. 54.9%). The positivity rate of anti-C100 and/or anti-P22 antibodies was 73.0% (46/63) in alcoholic cirrhosis. We performed a multivariate analysis on the effects of age, sex, cumulative alcohol intake, anti-HCV antibodies, indocyanine green excretion test, and serum albumin on the development of hepatocellular carcinoma HCC in patients with cirrhosis, using Cox's proportional-hazards model, which revealed that anti-HCV positivity was the only independent prognostic variable for HCC in patients with alcoholic cirrhosis. The probability of HCC was significantly higher in the anti-HCV-positive patients than in the negative patients with alcoholic cirrhosis (p < 0.05). The 3-, 5- and 10-yr cumulative occurrence rate of HCC was, respectively, 13.3%, 41.3%, and 80.7% for anti-HCV-positive patients with alcoholic cirrhosis, compared with 0%, 8.3%, and 18.5% for anti-HCV-negative patients. In nonalcoholic patients with type C cirrhosis, the 3-, 5-, and 10-yr cumulative occurrence rate of HCC was 7.3%, 23.1%, and 56.5%, respectively. The follow-up studies indicate that hepatocarcinogenesis is hastened significantly in patients with alcoholic cirrhosis if they are positive for anti-HCV antibody, and that heavy alcohol consumption also is a risk factor for the development of HCC in patients with type C cirrhosis.

Adult↗

[Successful operation for two cases of an aneurysmal bone cyst of the rib].

An aneurysmal bone cyst involving the rib is very rare. A 43-year-old man and 49-year-old woman complained of pain and swelling on the chest. X-ray and CT revealed a local expansion and honeycomb lesion of the right 9th rib. Surgical excision of the rib were performed to remove the tumor completely. The histopathological examination revealed that the lesion consisted of many cavities filled with blood and trabecullae containing osteoid tissue and giant cells, showing it to be an aneurysmal bone cyst. Because of the potential for the rapid growth and difficulty in differentiation between benign and malignant rib tumor, an excisional biopsy should be considered for the treatment of an aneurysmal bone cyst of the rib.

Adult↗

[Successful operation for isolated cardiac rhabdomyoma of the right atrium].

A 12-year-old girl has experienced palpitation and dizziness, and presented atrial flutter with maximal heart rate of 220/min. Two-dimensional echocardiogram and chest MRI revealed a mass attached to the inter-atrial septum. Complete excision of the tumor including the atrial septum was performed without damage to tricuspid valve. The interatrial septal defect was closed primarily. Histology of the tumor was compatible with cardiac rhabdomyoma. Sinus rhythm was present and no tachycardia occurred in the postoperative period. On the literature, only one case of isolated cardiac rhabdomyoma developing in the atrium was reported and this is considered as the oldest operative case in Japan.

Child↗

Relationships of lipid and glucose metabolism with waist-hip ratio and physical fitness in obese men.

The waist-hip ratio (WHR) is an indirect index of abdominal type obesity which has been shown to be strongly correlated with the risk of coronary heart disease. Empirically, men who have a higher WHR seem to have a lower level of physical fitness. In the present study, the relationships of lipid and glucose metabolism with WHR and physical fitness were examined in 207 Japanese obese men. Physical fitness was evaluated by the oxygen uptake at the onset of blood lactate accumulation (OBLA-VO2; ml/kg/min) which corresponds to 4 mmol/l of blood lactate during graded exercise test and is one of the best indicators of the muscle oxidative capacity. The WHR and percentage of body fat (% body fat) were significantly correlated with OBLA-VO2. The WHR and % body fat were significantly related to each other. After adjusting for % body fat, a significant negative correlation was observed between the WHR and OBLA-VO2 (r = -0.24; P < 0.05). A multiple linear regression was calculated for parameters relating to lipids, and glucose and insulin areas separately, when the WHR, OBLA-VO2, % body fat and age were entered as independent variables. OBLA-VO2 significantly showed a negative relationship with triglyceride (TG), HDL-C/total cholesterol, and the insulin area, while the WHR was only independently related to TG. From these results, we conclude that the physical fitness level evaluated by OBLA-VO2, which represents the capacity of the aerobic metabolism in muscle, may thus be a determinant of lipid and glucose metabolism in obese men.

Adult↗

[Multi-institutional feasibility study of SDI test for its application to the adjuvant chemotherapy of gastric cancer].

For the purpose to evaluate the feasibility of SDI test, a drug sensitivity test, against resected gastric cancer a multi-institutional study called as consisted of multiple institute the 16th Specified Study was planned by Japanese Foundation for Multidisciplinary Treatment of Cancer. SDI test was performed individually in 15 institutes in Japan using surgically resected specimens from the patients with gastric cancer. The adjuvant chemotherapy in each case was selected by randomized stratification. The anticancer drugs used were tegafur and one of the following three drug, mitomycin C (MMC), adriamycin (ADM) and cisplatin (CDDP). The drug sensitivity of each tumor was assayed by SDI test. The strict quality control was necessary to unify the method and the technique of this test in 15 institutes. Tumor bearing nude mice were delivered to each institute and the test was performed simultaneously. The data of this test were sent by personal computer to our Department. The clinical feasibility of this test will be evaluated after accumulation of cases for the statistic analysis.

Chemotherapy, Adjuvant↗

Expression of MDR1 and glutathione S transferase-pi genes and chemosensitivities in human gastrointestinal cancer.

The relationship was analyzed between drug resistance and MDR1 (with MDR signifying multiple drug resistance) and glutathione S transferase-pi (GST-pi) gene expression in four stomach and four colon cancer cell lines. Northern blot analysis by pmdr1 probe showed that stomach cancer cell lines had no detectable level of MDR1 mRNA expression. By contrast, some levels of MDR1 mRNA expression were found in two colon cancer cell lines, indicating doxorubicin resistance. To examine the MDR1 mRNA in each cell level, in situ hybridization was used. It was found that all colon cell lines and two stomach cell lines had more silver grains per cell than KB cells (a human KB kidney epidermoid carcinoma cell line). However, the number of silver grains in each cell was heterogeneous in the colon and stomach cell lines. Low-level MDR1 mRNA expression could be detected even in cell lines without MDR1 mRNA expression by northern blot hybridization. These results suggest the possibility that all gastrointestinal cell lines can acquire multiple drug resistance. In addition, all examined gastrointestinal cell lines had high GST-pi mRNA expression. This GST-pi gene expression shows cisplatin resistance in the examined cell lines. Heterogeneity of GST-pi mRNA expression also was shown at the cellular level.

Adenocarcinoma↗

Cross-linking connectivity in bone collagen fibrils: the COOH-terminal locus of free aldehyde.

Quantitative analyses of the chemical state of the 16c residue of the alpha 1 chain of bone collagen were performed on samples from fetal (4-6-month embryo) and mature (2-3 year old) bovine animals. All of this residue could be accounted for in terms of three chemical states, in relative amounts which depended upon the age of the animal. Most of the residue was incorporated into either bifunctional or trifunctional cross-links. Some of it, however, was present as free aldehyde, and the content increased with maturation. This was established by isolating and characterizing the aldehyde-containing peptides generated by tryptic digestion of NaB3H4-reduced mature bone collagen. We have concluded that the connectivity of COOH-terminal cross-linking in bone collagen fibrils changes with maturation in the following way: at first, each 16c residue in each of the two alpha 1 chains of the collagen molecule is incorporated into a sheet-like pattern of intermolecular iminium cross-links, which stabilizes the young, nonmineralized fibril as a whole. In time, some of these labile cross-links maturate into pyridinoline while others dissociate back to their precursor form. The latter is likely due to changes in the molecular packing brought about by the mineralization of the collagen fibrils. The resultant reduction in cross-linking connectivity may provide a mechanism for enhancing certain mechanical characteristics of the skeleton of a mature animal.

Aldehydes↗

Collagen cross-linking of skin in patients with amyotrophic lateral sclerosis.

Collagen cross-links of skin tissue (left upper arm) from 11 patients with amyotrophic lateral sclerosis (ALS) and 9 age-matched control subjects were quantified. It was found that patients with ALS had a significant reduction in the content of an age-related, stable cross-link, histidinohydroxylysinonorleucine, that was negatively correlated with the duration of illness. The contents of sodium borohydride-reducible labile cross-links, dehydro-hydroxylysinonorleucine and dehydro-histidinohydroxymerodesmosine, were significantly increased and were positively associated with the duration of illness (r = 0.703, p less than 0.05 and r = 0.684, p less than 0.05, respectively). The results clearly indicate that during the course of ALS, the cross-linking pathway of skin collagen runs counter to its normal aging, resulting in a "rejuvenation" phenomenon of skin collagen. Thus, cross-linking of skin collagen is affected in ALS.

Aged↗