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Biomedical subjects

M Shimada

Publications and source records attributed to M Shimada.

At least 325 records · Page 18Linked to original sources
PubMed1998

Estimation of age from the femur of Japanese cadavers.

This study was designed to estimate the age at the death of cadavers by histomorphometry of the femur. Samples from 72 Japanese males from 43 days to 92 years old and 26 females from 2 to 88 years old were used. The thickness of sections was adjusted to 50-70 microns by grinding with sandpaper. The sections were not any decalcified. They were stained with Villanueva's bone staining powder and thionin dye. The microradiographs of the sections were obtained by a soft x-ray apparatus. The area, length, width, and perimeter of the perfect osteon and haversian canal were measured. The type II osteon number, osteon fragment number, and area of triangle were also determined. These parameters were examined by an image analyzer. The parameters of the osteon showed a high correlation coefficient with age (magnitude of r > or = 0.77), whereas those of the haversian canal were low (magnitude of r < or = 0.11). All parameters were subjected to multiple regression analysis for producing a multiple regression equation of age estimation. For the stepwise selection method, the perimeter of osteon, length of the haversian canal, and osteon fragment number were selected for the equation. Their multiple r2 and standard error of estimation were 0.8874 and 6.39, respectively. For the forward selection method, in addition to the above items, three parameters, the length of osteon, area of triangle, and width of osteon, were selected. Their multiple r2 and standard error of estimation were 0.9484 and 4.884, respectively. Bone staining was useful to clarify the demarcation between osteon and fragment, leading to increased accuracy of age estimation. However, precisely estimating age for the entire range from birth to 90 years was difficult.

Adult↗
PubMed1998

[Developmental plasticity of corticospinal projections in the spinal cord gray matter of normal and hemicortectomized rat].

In the previous study we demonstrated in rats that aberrant ipsilateral CST fibers were increased when the cerebral cortex was surgically ablated unilaterally during the neonatal period. Origin of these aberrant fibers was confirmed to involve collateral axons, ramified from their parent axons. In this study, possible plastic change and the critical period for the outgrowth of CST fibers into the spinal cord gray matter in the rat after unilateral (right side) cortical damage at different ages measured in days were examined using anterograde horseradish peroxidase (HRP). HRP was injected into the left sensorimotor cortex in both normal and experimental rats. In the normal control rats, the outgrowth of HRP positive axons into the spinal gray matter was first noticed at 7 day of age in the vicinity of the right dorsal funiculus, and then reached maximal density and extension at 10 and 14 days of age, respectively. From 21 days onwards, the density and extension of HRP positive axons in the gray matter decreased rapidly except in the medial part close to the dorsal funiculus. In rats whose right cerebral cortex were damaged at day 1 of age, the pattern of the outgrowth of HRP positive axons into the right gray matter was much the same as that in age-matched controls. However, significantly different from the control, many HRP positive axons were noted even in the contralateral gray matter. HRP-positive axons in the contralateral left gray matter were also abundant in the rats who sustained cortical damage at 7 and 14 days, but were decreased considerably when the cerebral cortex was damaged at 28 days of age. When damage occurred at 56 days of age, HRP-positive axons did not increase in the left gray matter, indicating that the critical period of axonal plasticity after localized damage was before 4 weeks of age in rats.

Animals↗
PubMed1998

Quality of life following esophagectomy with three-field lymphadenectomy for carcinoma, focusing on its relationship to vocal cord palsy.

To clarify the quality of life of patients who underwent esophagectomy for carcinoma by right thoracotomy, laparotomy and cervical anastomosis, 116 patients who were cancer free at the time of mailing a questionnaire were analyzed. A significant decrease in vital capacity for 3 years postoperatively, as well as in the percentage of ideal body weight, between 3 and 5 years were observed in 57 patients with three-field lymphadenectomy. Patients' quality of life undergoing three-field dissection was worse than those with less radical lymphadenectomy (59 cases) in terms of the performance status and difficulty in talking at 60 months or more postoperatively. Around 20% of all patients reported severe hoarseness due to permanent recurrent nerve paralysis, resulting in poor quantity of food intake at 24 months or less postoperatively and restricted daily activity and difficulty in talking at 60 months or more after the operation. When a patient suffers from vocal cord insufficiency caused by permanent paralysis of the recurrent nerve, early treatment before discharge from the hospital should be performed to improve the quality of life of such a patient.

Aged↗
PubMed1998

[Clinical study on chlormadinone acetate alone followed by combination with LH-RH analogue for prostatic cancer: effects on lipid metabolism].

Twenty-four previously untreated patients with a diagnosis of prostatic cancer were treated with chlormadinone acetate (CMA) alone (100 mg/day) for 4 weeks, and luteinizing hormone-releasing hormone analogue (LH-RHa) was added for the next 24 weeks. Marked decreases in blood LH, testosterone (T), prostate specific antigen (PSA), gamma-seminoprotein (gamma-Sm), and prostatic acid phosphatase (PAP) were observed after a single dose of CMA. T levels were significantly increased 3 days after the initial dose of LH-RHa, and did not return to the pretreatment level. There were no significant increases in any of the markers, nor were there any flare-up cases. Triglyceride levels, which were slightly elevated before the start of treatment, were significantly decreased 24 weeks after the completion of combined therapy. PSA was evaluated as partial response (PR) or better in 86.7% of the patients. Overall evaluation showed PR or better in 75.0% of the patients. These findings suggest that prior administration of CMA followed by combined administration with LH-RHa is useful in the treatment of prostatic cancer. No negative effects on lipid metabolism were observed at any time during the treatment period.

Aged↗
PubMed1998

Application of locoregional chemotherapy using lymph-directed substances in a canine transhiatal esophagectomy model.

We investigated whether lymph-directed substances injected into the mediastinal connective tissue of dogs reached the regional lymph nodes of the esophagus. In 46 dogs, 1.5 mL of cuttlefish particles or activated carbon particles containing 15 mg of bleomycin (CH-BLM) was injected at two sites: into the connective tissue between the trachea and the aorta via mediastinoscopy in 23 dogs (16 with cuttlefish particles and 7 with CH-BLM: mediastinal group), and into the crura of the diaphragm by means of laparotomy in 23 dogs (16 with cuttlefish particles and 7 with CH-BLM: crural group). Cuttlefish particles, distinguished by decolorization with melanin bleaching, showed selective affinity for lymphatics. When cuttlefish particles were injected into mediastinal connective tissue, the rate of staining (# of black-stain positive nodes/# of examined nodes) was higher in the crural group than in the mediastinal group. In the crural group, bleomycin activity in lymph nodes was higher in the regions from the neck to the abdominal para-aortic region than at the injection site, excluding the peri-gastric region. If the topography of lymphatics and lymph flow kinetics in man are similar to that of the dog, then the crura of the diaphragm appears to be a potentially effective site for applying loco-regional chemotherapy for carcinoma of the esophagus in patients undergoing transhiatal esophagectomy.

Animals↗
PubMed1998

[Surgical treatment of carcinoma of the cardia with special references to mediastinal extension and lymph node metastasis].

We retrospectively analyzed the clinicopathological findings in 141 patients with advanced cardiac cancer. According to histological type, 117 patients had an adenocarcinoma and 24 patients a squamous cell carcinoma. Curative resection was performed in 114 patients, whereas the remaining 27 patients underwent palliative resection. Preoperative endoscopic ultrasonography and abdominal ultrasound were useful for the diagnosis of esophageal invasion and lymph node metastases. Particularly, the classification of paraaortic lymph node metastasis by ultrasound was important in deciding on the surgical method. Mediastinal lymph node metastases were found histologically in 19 of 68 patients. The survival of patients with mediastinal lymph node metastasis was poor. However, among them, a favorable outcome was expected for patients with few involved nodes and if only perigastric node involvement in abdominal nodes was found. Paraaortic lymph node metastasis was found histologically in 15 of 48 patients (27.9%). Two of 35-year survivors had 5 or fewer lymph node metastases, and showed only perigastric and paraaortic node involvement. It is equally important that tumor extension and lymph node metastases in the mediastinum and abdomen should be determined in the surgical treatment of advanced carcinoma of the cardia.

Adenocarcinoma↗
PubMed1997

Adenosquamous carcinoma of the liver: clinicopathologic characteristics and cytokeratin profile.

BACKGROUND: The clinicopathologic characteristics, biologic behavior, and histogenesis of primary adenosquamous carcinoma (ASC) of the liver have yet to be fully clarified. METHODS: Eight cases of ASC of the liver were analyzed both clinicopathologically and immunohistochemically using antibodies of cytokeratin (CK) 7, CK 8, CK 18, CK 19, and CK 903 (CK 5, CK 10, CK 11, and CK 14). The survival curve of the 6 patients with surgically resected ASC was compared with that of the 32 patients with common cholangiocarcinoma (CC). RESULTS: Most ASCs had invasive pathologic features, including venous invasion, lymphatic permeation, and intrahepatic metastases. There were lymph node metastases from 7 tumors (88%), and most of the metastases were adenocarcinoma. All adenocarcinoma (AC) components were positive for both CK 7 and CK 19. The squamous cell carcinoma (SCC) components were positive for CK 7 in all cases but were positive for CK 19 in only 5 cases (62.5%). The ACs were positive for CK 903 in only 3 cases (37.5%), whereas all SCCs were positive for CK 903. Almost all ACs were positive for both CK 8 and CK 18, whereas the SCCs were positive for CK 8 in only 3 cases (37.5%) and for CK 18 in no cases. All 6 patients with surgically resected ASC died of the disease within 1 year postoperatively. Their survival curve was significantly worse than that of the 32 patients with common CC (P < 0.001). The two patients on whom autopsy was performed also died within 1 year after diagnosis. CONCLUSIONS: ASC tended to have more aggressive biologic behavior and a poorer prognosis than common CC. The authors' immunohistochemical analysis of CK expression indicated that most of the ASCs of the liver that were studied developed from a squamous transformation of the preexisting CC.

Aged↗
PubMed1997

A recurrent translocation, t(16;21)(q24;q22), associated with acute myelogenous leukemia: identification by fluorescence in situ hybridization.

Chromosome fluorescence in situ hybridization (FISH) analyses were performed on bone marrow cells in 3 adult patients with MDS or AML with a (16;21)(q24;q22) translocation. FISH analyses with AML1 probes at 21q22 proved in all 3 patients splitting of the AML1 gene at a region spanning exons 5 and 6 and the translocation of its 5' segment to distal 16q. Chromosome painting FISH analysis in patient 1 proved the translocation of the distal 21q segment to 16q, but it failed to prove the presumed translocation of the distal 16q segment to 21q, most likely because of its small size.

Adult↗
PubMed1997

A specific loss of growth hormone abolished sex-dependent expression of hepatic cytochrome P450 in dwarf rats: reversal of the profiles by growth hormone-treatment.

A spontaneous dwarf rat derived from a colony of Sprague-Dawley (SD) strain has no detectable level of growth hormone (GH) in pituitary, although it contained other hormones like prolactin and ACTH. Hepatic profile of cytochrome P450 (P450) differed clearly between dwarf and normal SD rats. A male-specific form of P450, CYP2C11, was detected in dwarf male rat livers, while the level was one-third of the normal SD livers. This P450 was also detected in dwarf females. Other male-specific CYP3A2 and CYP3A18 were also contained in both sexes of dwarf rats, whereas a female-specific form, CYP2C12, was not detectable in dwarf females. Phenobarbital-inducible CYP2B1 and CYP2B2 were constitutively expressed in dwarf rats, although substantially absent in normal SD rats. To assess the role of GH on hepatic P450 expression, GH was given to dwarf rats for 7 to 9 days. The intermittent injection (mimicking the male secretory pattern) resulted in the elevation of CYP2C11 to a level as observed in normal SD males. Continuous infusion of GH (mimicking the female secretory pattern) evoked CYP2C12 in livers of both sexes of dwarf rats, whereas the treatment decreased levels of CYP3A2, CYP3A18, and CYP2B1. These results clearly demonstrate that specific defect of GH, but not pituitary, cause the clear changes in hepatic P450 forms including sex-specific forms. The present study provides evidence further to strengthen the principal role of GH on the regulation of expression of P450 in rat livers.

Animals↗
PubMed1997

Indications for palliative reduction surgery in advanced hepatocellular carcinoma. The use of a remnant tumor index.

OBJECTIVES: To clarify the indications for and the significance of palliative reduction surgery in the multidisciplinary treatment of advanced hepatocellular carcinoma (HCC) and to propose the use of a remnant tumor index (RTI) as a simplified criterion for palliative reduction surgery in cases of advanced HCC. DESIGN: A comparison of survival based on the RTI. SETTING: A large university hospital in Japan. PATIENTS: Twenty-five patients with advanced HCC who underwent palliative reduction surgery were divided into 3 groups as follows: group 1 (n = 9), the remnant tumor after operation existed only in the liver and the RTI was less than 5.0; group 2 (n = 11), the remnant tumor after operation existed only in the liver and the RTI was greater than 5.0; and group 3 (n = 5), extrahepatic metastatic tumor existed after operation. MAIN OUTCOME MEASURES: Pathological findings and survival rate after surgery. RESULTS: There was no significant difference in the degree of macroscopic intrahepatic metastases among the 3 groups; however, both the portal vein invasion and the histological grade tended to be more severe in groups 2 and 3. The respective 1-year and 3-year survival rates for group 1 were 67% and 33%, and those for group 2 were 21% and 0%. There were no survivors in group 3 at 1 year after surgery. Significant differences were found in the survival rates between groups 1 and 2 (P < .05), and between groups 1 and 3 (P < .05). CONCLUSION: Palliative reduction surgery for advanced HCC is only considered effective for patients with both an RTI of less than 5.0 and no extrahepatic metastasis.

Aged↗
PubMed1997

Lymph node and perinodal tissue tumor involvement in patients with esophagectomy and three-field lymphadenectomy for carcinoma of the esophagus.

BACKGROUND: Lymph node metastasis is a definitive prognostic factor; however, perinodal fat tumor invasion has not been fully elucidated. METHODS: Periesophageal nodes and the surrounding fibrofatty tissue obtained from 131 patients who underwent esophagectomy were examined. RESULTS: Of 9,789 nodes removed, 645 (6.6%) demonstrated invasion and 143 (1.5%) showed perinodal involvement. Of 131 patients 97 (74.0%) had lymph node involvement and 43 (32.8%) had perinodal fat involvement. The incidence of perinodal tissue involvement correlated significantly with the number of nodes involved; 23 (42.6%) of 54 patients with a total of 1-8 nodes involved and 19 (95.0%) of 20 patients with 9 or more involved nodes had perinodal involvement. The 5-year survival for 33 patients without involved nodes or perinodal tissue extension was 59.7%, compared to 14.0% for 43 patients with perinodal fat involvement. CONCLUSION: Perinodal tissue carcinoma into the periesophageal fibrofatty tissue was a decisive prognostic factor in patients with curative resection for esophageal carcinoma.

Adipose Tissue↗
PubMed1997

Significance of alpha-fetoprotein levels for detection of early recurrence of hepatocellular carcinoma after hepatic resection.

BACKGROUND: The recurrence of hepatocellular carcinoma (HCC) after surgery is common. The present study was conducted in order to clarify the significance of alpha-fetoprotein (AFP) in the detection of the early recurrence of HCC after surgery. METHODS: Fifty-eight patients who underwent a curative hepatic resection for HCC and whose preoperative AFP levels were >100 ng/ml, were selected for this study. RESULTS: In 26 cases, the postoperative AFP levels within 3 months after surgery did not decrease to <20 ng/ml (high AFP group). In the other 32 cases, the postoperative AFP levels within 3 months after surgery decreased to <20 ng/ml (low AFP group). No significant difference was observed in clinical or pathological backgrounds. The postoperative disease free rate in the low and high AFP groups was 84.2% and 18.4%, at 1 year, 61.2 and 4.6% at 3 years, respectively. The difference was statistically significant (P < 0.01). At the time of recurrence, the AFP levels increased in 25 (96.2%) of the patients who had early recurrence within 1 year after surgery as well as in 11 of 14 (78.5%) who had recurrence >1 year after surgery. The interval from surgery to recurrence significantly correlated with the doubling time of AFP at the time of recurrence in patients with early recurrence (within 1 year after hepatectomy) (r = 0.60, P < 0.01). In cases in which the preoperative AFP level was >100 ng/ml and the postoperative AFP level did not decrease to <20 ng/ml, early recurrence within 1 year after surgery would thus be strongly suspected. CONCLUSION: The measurement of the AFP levels after surgery is therefore considered to be important in the follow-up of hepatectomized patients, especially regarding the detection of early recurrence.

Aged↗
PubMed1997

Usefulness of ED036 kit for measuring serum PIVKA-II levels in small hepatocellular carcinoma.

As a tumor marker for hepatocellular carcinoma (HCC), serum protein induced by vitamin K absence or antagonist-II (PIVKA-II) has high specificity, yet its sensitivity is relatively low, marking it less suitable to serve as an adjunct in the diagnosis of small HCC. Recently, the ED036 kit (Eisai, Tokyo, Japan), whose detection limit is approximately ten times superior to that of a conventional kit (Eitest MONOP II, Eisai) has been developed. In this study, serum PIVKA-II levels in serum samples from 83 patients with benign chronic liver diseases (CLD) and 129 patients with HCC were measured with those two kits. With the ED036 kit, the cut-off value was set at 40 mAU/ml. For PIVKA-II measured with the ED036 kit, sensitivity was 45.0%, specificity 92.8%, and accuracy 63.7%, when we discriminated patients with HCC from those with CLD without HCC. While maintaining a high specificity, of 92.8%, the ED036 kit showed a significantly higher sensitivity than the conventional kit (45.0% versus 27.9%; P < 0.0001). With patients who had HCC consisting of a single nodule 30 mm or less in diameter, the positivity rate for serum PIVKA-II with the ED036 kit was significantly greater than the rate with the conventional kit (21.4% versus 9.5%; P < 0.005). Thus, the ED036 kit was thought to be more useful than the conventional kit as a tumor marker for small HCC.

Adult↗
PubMed1997

Enhancement of therapeutic efficacy of bleomycin by incorporation into biodegradable poly-d,l-lactic acid.

A new system for the delivery bleomycin (BLM) to target lesions was established by incorporating BLM into a small cylinder of a biodegradable polylactic acid (PLA) of low molecular weight. Cross-sectional analysis of the system (BLM-PLA) showed that BLM particles were uniformly enclosed in the PLA matrix. In vitro studies demonstrated that BLM was released continuously for more than 3 weeks from BLM-PLA immersed in saline. BLM-PLA was implanted subcutaneously into the backs of rats. A high concentration of BLM was maintained in the connective tissues near the implants for 2 weeks. In contrast, the level of BLM activity was low when a BLM solution (BLM-SOL) was administered subcutaneously by injection. The concentration of BLM in the abdominal lymph nodes was significantly higher following BLM-PLA implantation than following subcutaneous BLM-SOL injection. The inhibitory effects of BLM-PLA and BLM-SOL on tumor growth were compared with no treatment using a subcutaneously transplanted Yoshida sarcoma. The antitumor effect of BLM-PLA was significantly higher than that of BLM-SOL and no treatment. BLM-PLA also resulted in a more favorable distribution of BLM than BLM-SOL. Thus, BLM-PLA proved to be effective in controlling this experimentally transplanted tumor.

Animals↗
PubMed1997

Age-dependent susceptibility in mumps-associated hydrocephalus: neuropathologic features and brain barriers.

Central nervous system susceptibility to viral infection is often age dependent for unclear reasons. In this study, we examined the age-dependent susceptibility of the brain in mumps virus-induced hydrocephalus in hamsters, and evaluated the relationship between neuropathologic features and brain barriers using glial fibrillary acidic protein and zonula occludentes 1 (ZO-1) immunohistochemistry. In a group intracerebrally inoculated with mumps virus at 2 days of age, pathologic findings such as periventricular edema, ependymal cell loss, and ventricular dilation were more prominent and the distribution of mumps virus antigen was wider than in a group inoculated at 30 days of age. ZO-1-immunoreactive tight junctions in the hydrocephalic brains of the 2-day group were severely damaged in the choroid plexus and ependyma, and in white matter capillaries as early as 3 days after inoculation. These changes were not apparent in the hydrocephalic brains of the 30-day group. Prominent cortical dissemination of virus in the 2-day group was related to underdeveloped perivascular glial foot processes in brain parenchyma. Periventricular edema in the 2-day group was linked to ependymal and blood-brain barrier tight-junction permeability. Our results suggest that tight junctions in the early postnatal period are more immature and fragile than in the adult. We concluded that brain susceptibility in mumps virus-induced hydrocephalus is intimately related to the maturity of brain barriers.

Aging↗