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Biomedical subjects

Y Noguchi

Publications and source records attributed to Y Noguchi.

At least 325 records · Page 18Linked to original sources

Initial gingival tissue attachment to the deep cementum.

This study was performed in order to obtain fundamental knowledge regarding gingival connective tissue response to cementum. Gingival tissues of monkeys were elevated, and superficial cementum only was curetted. The time course of initial gingival tissue attachment was subsequently examined by conventional histology and also by electron microscopy. The first response was inflammatory exudate and fibrin attachment followed by granulation tissue formation. Cementoblasts were observed along the curetted cementum surface in the 10-day specimen. Mature collagen fibrils accumulated between the cementoblasts and the cementum surface in the 14-day specimen. We conclude that curetting the superficial cementum from root surfaces facilitates the formation of the fibrous connective tissue attachment.

Animals↗

[Fundamental and clinical studies of extracorporeal shock wave lithotripsy (ESWL) for pancreatic duct stones].

The application of ESWL for pancreatic duct stones was studied clinically, and the safety of this technique was also investigated experimentally. In 12 patients suffering from chronic pancreatitis and having calcified stones in the main pancreatic duct, ESWL was performed. None of the patient had received endoscopic pancreatic sphincterotomy before ESWL. Stone disintegration was obtained in all cases, and the main pancreatic duct stones completely disappeared in 9 of 12 cases. As a result, not only exacerbation of pancreatitis was removed, but also the preservation of pancreatic endocrine and exocrine functions was suggested. With regard to complications, no abnormalities were observed experimentally in the pancreatic parenchyma of treated dogs, and similarly no acute symptoms were recognized in the patients with pancreatic duct stones. ESWL for pancreatic duct stones is low in stress for the patient, and is effective for large stones. We therefore conclude that ESWL might be an extremely useful, new non-surgical treatment approach to control of pancreatic duct stones.

Adult↗

An ultrastructural study comparing new gingival tissue attachment on chemically exposed fibrils and retained periodontal ligament.

Successful periodontal healing has been demonstrated in animals following application of citric acid to exposed root surface. However, we have been unable to achieve comparable results on clinical patients. Accordingly, the present study, using monkeys, was designed to re-evaluate the degree of interdigitation of newly-formed gingival fibrils with ones exposed to citric acid compared to normal attachment tissues of the retained periodontal ligament. We found that superficial collagen fibrils in both cases suffer degradation following normal inflammation and healing secondary to flap surgery. On retained periodontal ligament tissues, this change was limited to superficial levels and newly-formed collagen fibrils were linked immediately with old ones. In contrast, when exposed collagen fibrils were conditioned by exposure to citric acid, the degradative change occurred more deeply, and healing was delayed. Thus, the citric acid may not be the best choice of root treatments in terms of promoting better gingival tissue attachment. Furthermore, the results indicated that fibrils preserved on the root should not be curetted as possible during flap surgery as they offer an improved chance for optimal reattachment.

Animals↗

[Enhanced effect of intraperitoneal administration of CDDP combined with caffeine against peritoneal metastasis].

The enhanced effect of CDDP combined with caffeine against P-388 leukemia was investigated. No synergistic effect was shown after one hour simultaneous treatment with CDDP and caffeine. But the growth inhibition was enhanced by the addition of caffeine after one hour treatment with CDDP. It is suggested that caffeine inhibits DNA repair by the reduction of CDDP-induced elongation of G2 + M phase. The increase in life span of mice after ip transplantation was observed by frequent ip injections of caffeine after CDDP injection. It is suggested that the effect of intraperitoneal administration of CDDP against peritoneal metastasis is enhanced by combination with caffeine.

Animals↗

[Significance of blood vessel invasion in gastric carcinoma--prediction of liver metastases from the blood vessel invasion in the primary tumors].

This study was conducted to elucidate the factors related with liver metastases, to clarify the significance of blood vessel invasion and then to predict liver metastases from these findings. Patients examined were 102 cases which underwent gastrectomy and were followed-up for more than 5 years or until death at our department. Two new staining methods were applied in this study; Victoria blue + hematoxylin eosin double staining for elastic fiber and Factor VIII related antigen for vascular endothelium. Significant differences in qualitative frequency of blood vessel invasion, the number of lymph node metastases, and the depth of invasion were found in those patients with liver metastases, as compared with 5 year survivors. Quantitative analysis of blood vessel invasion revealed significant importance of blood vessel invasions in the submucosa, in the forms of complete thrombus, wall invasion and partial thrombus, in the diameters of 0.01-0.1 mm and 0.1-1.0 mm. Applying discrimination coefficients of linear discrimination analysis, prediction of liver metastases was possible with 81.8% sensitivity, 85.3% specificity, and 83.6% accuracy. Liver metastases can be predicted from the qualitative and quantitative analyses of blood vessel invasion in the primary tumors by elastic fiber staining.

Gastric Mucosa↗

[Initial clinical experience with video-cystoscope].

The endoscopic image processing system which has a very small change coupled device (CCD) at the distal tip of an endoscope, can give us a quite different imaging information from the conventional optical endoscopes, of which the main functions were just to "see inside the human body". The advantage of this endoscopic image processing system has been well recognized but, since the scope diameter could not be made smaller due to the size limitations of the CCD chip itself, the system has not been utilized in the field of Urology. In cooperation with Olympus Optical Co., we have studied a system called Urological Video Information System (UVIS) in order to utilize the image processing system for Urology. In our system a special light source with RGB light output is utilized together with a conventional optical cystoscope and a video converter is connected to the eyepiece of the scope in order to observe endoscopic images on the monitor. Endoscopic images can be stored in an image filing system when necessary. The image quality of UVIS is inferior to that of the conventional cystoscopes at the moment and there are several other technical problems to solve but, as witnessed in the field of Gastroenterology, it is expected that this kind of electronic system will become much more important in the future. This report covers the current problems and some considerations of them as an initial study.

Acute Disease↗

[Quality of life of patients after esophagectomy for esophageal cancer].

Quality of life of 79 patients who underwent esophagectomy for esophageal cancer and survived more than one year was evaluated by a questionnaire method. About 90% of patients had a good appetite, taking ordinary solid foods, and 69% were satisfied with the daily amount of foods. About 40% of patients complained of passage disturbance on swallowing, abdominal pain or diarrhea after meal. Fifty seven per cent of patients had frequent episodes of cough and sputum, and 20% were not able to go up the stairs to the third floor because of short breath. Thirty two per cent of patients with recurrent nerve paresis and even 5% without paresis had a trouble in daily conversation. These physical distresses were thought to be useful indicators for the doctor to evaluate the quality of life of patients. Additionally, about 30% of patients had a tendency of mental depression postoperatively. Fifty six per cent of patients who had worked before operation returned to work or were doing a lighter work than before. The psychological factor and social rehabilitation were suggested to be very important, when evaluated from the patient's side. Especially in case of aggressive surgery for esophageal cancer, postoperative quality of life of patients should be carefully considered from the viewpoints of both the patient and doctor.

Aged↗

[Clinical studies and morphological response on ST-95 (fosfomycin)].

Clinical effects of ST-95 (fosfomycin) on infections of the urinary tract were studied on the basis of morphological changes of the urinary bacteria. The subjects were 22 inpatients with complex infections of the urinary tract. ST-95 was dissolved in physiologic saline (2 g/100 ml) and administered intravenously by drip infusion over a 1-hour period twice daily for 5 days. According to the UTI criteria, the treatment was effective in 13 (81%) of the 16 evaluable cases. The present effectiveness in 8 patients with chronic catheterization was 75%. No side effects were observed in any patient. Among the laboratory data, GOT and GPT were slightly increased in 1 patient, but their relations with the treatment were unknown. In one patient (P. vulgaris; MIC: 12.5 micrograms/ml), changes in the urinary ST-95 concentration, viable bacterial count, and morphology of the bacteria were studied after the initial administration. The urinary viable cell count was 1.5 x 10(7) cells/ml before administration, but it was reduced to 1.6 x 10(4) cells/ml at the end of the 1-hour infusion, and decreased progressively thereafter to complete disappearance after 12 hours. Under differential interference microscopy, filamentous debris of bacteria and spherical bacteria with irregular surface were observed from immediately after the end of the administration. By transmission electron microscopy, the cell wall showed a number of projections with formation of vacuolar structures in the space between the cell wall and the irregularly-shaped cytoplasms. In conclusion, the results of administration of ST-95 in complex infections of the urinary tract were satisfactory. The morphological changes of the bacteria suggested that this agent acts at an early stage of cell wall synthesis.

Bacteria↗

The effect of neonatal exposure to chronic footshock on pain-responsiveness and sensitivity to morphine after maturation in the rat.

Rat pups in 3 groups respectively were given daily footshock, exposure to a footshock apparatus without shock, or no handling from birth to 21 days of age and reared with no manipulation afterwards. After maturation (90-100 days of age), they were assessed for hot-plate paw-lick latency, morphine-induced analgesia and opiate receptor binding assay. In footshocked animals, a significant increase was found in paw-lick latency and in antinociceptive effects of morphine (1.25, 2.5, and 5.0 mg/kg) in comparison with two control groups. The antinociceptive effect of morphine in all 3 groups was antagonized by pretreatment with naloxone (2.0 mg/kg). No significant difference was found in binding activities (Bmax and Kd) for both [3H]naloxone and [3H]Dala2, D-Leu5-enkephalin between the 3 groups. These results suggest that exposure to footshock stress in the preweanling period has a long-term effect on the sensitivity of rats to painful events, probably due to chronic functional changes in endogenous opiate systems at presynaptic level rather than in postsynaptic opiate receptor binding activity.

Aging↗

Thymolipoma: a report of three cases.

Three cases of thymolipoma, seen in a 6 year old boy, a 34 year old woman and a 24 year old man are presented herein. The weight of each tumor was 1380 g, 670 g and 560 g respectively. The 2 male patients had no symptoms and the woman only complained of a fever. On CT scan the thymic tissue was recognized as islands of soft tissue density within a fatty mass, and T1 weighted MRI was helpful in demonstrating the predominant fatty nature of this tumor. Thus, our experience demonstrates that CT and MRI are valuable for establishing a diagnosis of thymolipoma. In a review of the literature on the subject, some clinical features of this non-malignant tumor in the mediastinum are discussed. Although rare, thymolipoma should be considered in the differential diagnosis of mediastinal tumors.

Adult↗

Lipid kinetic alterations in tumor-bearing rats: reversal by tumor excision.

Cancer cachexia is frequently accompanied by hyperlipidemia. To identify the mechanisms underlying this alteration in lipid metabolism, free fatty acid (FFA) and very low density lipoprotein-associated triacylglycerol (VLDL-TG) kinetics were determined in tumor-bearing (subcutaneously implanted methylcholanthrene-induced sarcoma) Fischer 344 rats. The animals were studied after chronic vascular catheterization, in an unanesthetized, undisturbed state, after 24 hr of fasting. They were separated into three groups: control (n = 5), tumor-bearing (n = 5, tumor burden = 10% body weight), and 7 days after tumor excision (n = 5). VLDL-TG and FFA kinetics were assessed by a constant infusion of [3H]palmitate-labeled VLDL-TG and [14C]palmitate bound to albumin, respectively. FFA rate of appearance (FFA-Ra) and clearance (FFA-Cl) and VLDL-TG rate of appearance (VLDL-TG-Ra) and clearance (VLDL-TG-Cl) were determined at steady state. We observed that the tumor-bearing rats had significantly increased FFA-Ra and VLDL-TG-Ra, decreased VLDL-CL, and maintained FFA-Cl, when compared to control. These alterations returned to normal levels after tumor excision. The results suggest that the hyperlipidemia observed in tumor-bearing rats is due to elevated lipolysis rate, maintained rate of plasma FFA clearance, increased triacylglycerol production and VLDL secretion by the liver, and decreased VLDL-TG clearance from plasma. These alterations were reversed 7 days following tumor excision.

Animals↗

The effect of increased intracranial pressure during the appearance of pressure waves on the brainstem.

The effects of increased intracranial pressure (ICP) during the appearance of plateau waves or B-waves to the brainstem functions were investigated by evaluation of evoked potentials. The ICP and systemic blood pressure were continuously recorded in nine cases of intracranial hypertension. In the four cases demonstrating plateau waves in ICP recording, the latencies of the auditory brainstem evoked potentials (ABEP) measured during the appearance of plateau waves showed no significant differences compared to those measured during the interval phase between two plateau waves. In the five cases demonstrating B-waves in ICP recording, four cases showed significant (p less than 0.05) prolongation of the V wave of ABEP and three showed significant (p less than 0.05) prolongation of the P15 of somatosensory evoked potentials during the phase of increased ICP level with B-waves compared to those measured during the phase of decreased ICP level without B-waves, produced by external drainage of the cerebrospinal fluid or mannitol administration. The results indicated that during the appearance of plateau waves there were no significant changes of electrical activity in the brainstem, even though there was a significant reduction in cerebral perfusion pressure. It is suggested that in cases with the appearance of B-waves, an increase in ICP frequently affects the electrical activity in the brainstem.

Aged↗

[Pathological studies of the bladder wall after contact Nd:YAG laser irradiation in the treatment of bladder cancer].

A total of 75 cases of bladder tumors were treated with contact Nd:YAG laser therapy from February 1984 to April 1988. In 14 of 75 cases post-therapeutic total cystectomy was performed and laser irradiated areas were evaluated pathologically. The results were as given below. 1. The irradiated area a was well demarcated from the non-irradiated area and had ulceration and granulation. 2. Ulceration extended to the deep muscle layer but no perforations were noted in any cases. 3. Although intensive edema was present in the fresh granulation, by approximately Post-irradiation week 3 the fibroblast cells and the fibrous cells had appeared and new vascular growth was manifest. A year later very small scarred tissues, distinctly demarcated from the surrounding tissues, appeared or the granulation was absorbed. Carbonized foreign bodies were incorporated in the granulation with the confirmed presence of the giant cells ingesting the foreign bodies. 4. With the exception of two cases where eosinophilic invasion was predominant, neutrophilic infiltration was predominant in the granulation throughout the cases. 5. In cases at Stage T3, the irradiated beds were suspected of having residual cancer cells. 6. Contact irradiation would not be accompanied by transfer of the cancer cells. It was concluded that contact Nd:YAG laser therapy could be safely instituted in the treatment of bladder tumors in which transurethral treatment would be indicated.

Aged↗

Blood vessel invasion in gastric carcinoma.

In an effort to identify factors in primary tumors that would predict liver metastases, we retrospectively reviewed 102 patients with gastric cancer, and their tissue blocks were restained. New staining methods for elastin and endothelium were used to identify intratumoral vessels. Blood vessel invasion, thus detected, was analyzed quantitatively, as well as qualitatively, according to the location of invasion, the size of the involved vessel, and the mode of invasion. The invasion was then compared with the presence of liver metastasis by the chi 2 test, the Mann-Whitney U test, and the Student t test. Discrimination analysis of factors significantly correlated with liver metastasis was performed with linear discrimination function to identify a predictive model for liver metastasis. Significant differences in qualitative frequency of blood vessel invasion (p less than 0.01), the number of lymph node metastases (p less than 0.05), and the depth of tumor invasion (p less than 0.05) were found in those patients in whom liver metastasis developed, as compared with 5-year disease-free survivors. Quantitative analysis of blood vessel invasion revealed eight other factors correlated with liver metastasis; frequency of blood vessel invasion in the 0.01 to 0.1 mm and 0.1 to 1 mm diameter vessels, in the forms of complete, partial tumor thrombi, and vessel wall invasion, in the submucosa and the subserosa, and the number of anatomic stomach layers involved. Application of the discrimination coefficient to these factors allows prediction of liver metastasis with 81.8% sensitivity, 85.3% specificity, and 83.6% accuracy. Liver metastasis can be predicted from the qualitative and quantitative examination of blood vessel invasion within the primary tumor by the use of an elastic fiber stain.

Capillaries↗

Comparison of cytologic markers for automated lung cancer screening.

In a preliminary study for the development of an automated lung cancer cytology screening system utilizing both flow and image processing techniques, potential markers for the flow cytometric screening for carcinoma cells in sputum were analyzed. Immunostains were applied by the avidin-biotin peroxidase complex method, using antibodies to keratin (55-57 KD), TA-4 and SCC (antigens of squamous cell carcinoma of the human uterine cervix), neuron-specific enolase (NSE), gastrin-releasing peptide (GRP) and carcinoembryonic antigen (CEA), to carcinoma cells from 123 cases with lung cancer (35 with squamous cell carcinomas, 64 adenocarcinomas, 13 large cell carcinomas, 5 small cell carcinomas and 6 other histologic types) and to sputum cells from 113 cytologically negative cases (as controls). The positive rates were 60.1% for keratin, 34.8% for TA-4, 28.2% for SCC, 1.4% for NSE, 0.1% for GRP and 7.9% for CEA for carcinoma cells (P less than .05 for all) and 7.4% for keratin and 1.0% for SCC for sputum cells (P less than .05 for both). It was concluded that keratin is the most effective marker, not only for squamous cell carcinoma, but also for adenocarcinoma and large cell carcinoma. Since most small cell carcinoma cells in sputum have little or no cytoplasm, it is necessary to use an intranuclear marker to detect this histologic type.

Antibodies, Monoclonal↗

Possible involvement of bone cells in a new cementum formation.

Cells from the gingival lamina propria, bone-derived granular tissues and periodontal ligament (PDL) were isolated after periodontal surgery and subsequently cultured in vitro. The resulting cells were defined as gingival cells, bone cells and PDL cells, respectively. Under a phase contrast microscope, the cultured cells exhibited a spindle and/or a polyhedral shape. On the basis of their appearance under an electron microscope, spindle-shaped cells and polyhedral-shaped cells were identified as fibroblasts and osteoblasts, respectively. Bone cells, a homogeneous population of osteoblasts, had a more rapid growth ability than PDL cells, which were a heterogeneous population of fibroblasts and osteoblasts. Of particular interest was that only bone cells produced bone matrix in the multilayers in vitro. These results support the hypothesis that the phenotype expressed by cells from the alveolar bone establishes a new concept for progenitor cells in the formation of cementum.

Alveolar Process↗

Role of adrenergic activity in ischemic brain edema.

Thirty male Wistar rats, weighing 200 to 300 g, were used for this study. During a 3- to 4-min period, 300 micrograms of 6-OHDA was injected stereotactically into the right lateral ventricle. The same amount of saline was injected into the ventricle for the control group. Seven days after this procedure, the right common carotid was occluded with a clip and 4 to 6 ml of blood was removed from the external jugular vein to reduce the blood pressure. The clip was removed in 2 hr, and blood flow was maintained for 1 hr. The SG of cerebral tissue was measured according to the method of Marmarou et al. The disruption of BBB was examined by Evans blue injection, and the brain tissue was also examined by electron microscopy. Rats with 6-OHDA treatment had brain edema although the control group had no edema. We suggest that the depletion of brain NA could cause a disturbance in cerebral microvascular tone and could make cerebral blood vessels more vulnerable to the decreased CBF when followed by restoration of the blood flow.

Animals↗

[A case of giant thymolipoma in a child].

A case report of a giant thymolipoma in 6-year-old boy is reported. Following school screening, an abnormal shadow in the left chest was found on the chest X-ray. CT scan and MRI suggested the mediastinal tumor containing a fatty mass. The tumor was resected on bloc through the median sternotomy and left antero-lateral thoracotomy. The tumor was 85 X 210 X 140 mm in size and 1380 g in weight. The postoperative histological examination revealed the thymolipoma. We were able to find only 19 other reported cases of thymolipoma in Japanese literature. Of 19 cases, this thymolipoma is the largest one in proportion to the patient's body weight.

Child↗