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M Ohsawa

Publications and source records attributed to M Ohsawa.

At least 19 recordsLinked to original sources

Expression of Epstein-Barr virus latent infection genes and oncogenes in lymphoma cell lines derived from pyothorax-associated lymphoma.

Malignant lymphomas frequently develop in the pleural cavity of patients with long-standing pyothorax. The term pyothorax-associated lymphoma (PAL) has been proposed for this type of tumor. Most PALs are diffuse lymphomas of the B-cell type and contain Epstein-Barr virus (EBV) DNA. We have established 2 lymphoma cell lines from biopsy specimens of PAL cases, OPL-1 and OPL-2, and examined their growth characteristics and the expression of EBV latent infection genes and oncogenes. OPL-2 exhibited a more rapid growth and higher saturation density than OPL-1, and only OPL-2 exhibited colony-forming activity in soft agar. OPL-1 and -2 were positive for B-cell differentiation markers and showed clonal surface immunoglobulins. Both line contained a single predominant form of episomal EBV DNA, indicating clonal cellular proliferation of an EBV-infected progenitor cell. OPL-1 and -2 contained type B and A EBV genome, respectively. Expression of EBV nuclear antigen (EBNA)2 mRNA and protein was detected by Northern and Western blot analysis in OPL-1, but not in OPL-2. On the other hand, the expression of latent membrane protein (LMP)1 mRNA in both OPL-1 and -2 was extremely weak and detectable only by reverse transcription-polymerase chain reaction. Protein expression of LMP1 was not observed by Western blot analysis or immunocytochemistry. Both lines expressed c-myc mRNA. Only OPL-1 expressed mRNA of c-fgr, an oncogene whose expression is upregulated by EBNA2. Both OPLs expressed bcl-2 mRNA without detectable expression of LMP1 protein.

Aged

Epstein-Barr virus in Hodgkin's disease patients in Japan.

BACKGROUND: The association of Epstein-Barr virus (EBV) and Hodgkin's disease (HD) has been suggested by serologic, epidemiologic, and molecular biologic studies. The high level of EBV association with HD in the developing countries was discussed in relation to the high HD incidence in these areas. Japanese HD shows a distinct peak incidence in older adults. In contrast, Western HD shows a bimodal pattern, the first peak in young adulthood and a second peak in older patients. In the present study, the EBV association with HD in Japan was investigated, and the results were compared with those reported from industrialized and developing countries. METHODS: Fifty-seven patients with HD were studied for the presence or absence of the EBV genome by the polymerase chain reaction and in situ hybridization methods. Seven cases were excluded from the analysis for EBV because of poor preservation of nucleotides in the specimens. RESULTS: EBV genomes were detected in the Reed-Sternberg (R-S) cells of 32 of the 50 patients examined (64%). The EBV association was independently affected by histologic subtype (84% in mixed cellularity and 44% in others), sex (76% in males and 31% in females), and age (76% in patients aged 40 years and older and 38% in patients younger than 40 years of age; P < 0.01). High EBV association is found at the peak in older adults predominantly with mixed cellularity type. Previous studies revealed that the high EBV was associated with the older peak of the bimodal peaks in Western HD, and a unimodal peak in childhood in developing countries. The EBV subtype was predominantly type A, which is identical to the immunocompetent type of HD reported previously. CONCLUSIONS: The results of the current study, together with those reported previously, showed that the presence of the Epstein-Barr virus correlated with mixed cellularity type, age older than 40 years, and male sex.

Adolescent

Prognostic factors in angiosarcoma: a multivariate analysis of 55 cases.

Data for prognostic factors in angiosarcoma (AS) are limited, prompting a large-scale study of AS with multivariate analysis. To analyze prognostic factors in angiosarcoma (AS), clinical and histologic findings in 55 patients collected from hospitals in Japan were reviewed. Prognostic factors were evaluated by univariate and multivariate Cox's proportional hazards models. The study involved 32 males and 23 females, ages 18-93 (median, 69) years. The primary sites of tumors included head and neck (32 cases), trunk (10), extremities (3), spleen (3), breast (3), and other (4). The overall 2-year survival rate was 21%. Univariate analysis of clinical factors including age, sex, size and depth of tumor, tumor-related symptoms, interval between onset of symptoms and admission, surgical procedures, adjuvant chemotherapy, and adjuvant radiotherapy showed that age, tumor size, and mode of treatment were significant for survival. Histologic factors analyzed were mitotic counts, cellularity, cellular pleomorphism, extent of necrosis, vascular differentiation, and nonspecific diagnosis. Only mitotic counts were significant for prognosis. Multivariate analysis on these four factors revealed that tumor size, mode of treatment, and mitotic counts were independent prognostic factors.

Adolescent

Occurrence of monocytoid B lymphocytes in lymph nodes of patients treated by chemotherapy.

Occurrence of monocytoi B lymphocytes (MBL) in the lymph nodes of patients receiving preoperative chemotherapy for cancer was examined and compared to lymph nodes in controls who had not received chemotherapy. Number of patients receiving and not receiving preoperative chemotherapy were 3 and 10 cases in ovarian cancer, 7 and 11 in testicular cancer, and 22 and 8 in lung cancer, respectively. Chemotherapeutic agents for ovarian, testicular, and lung cancer consisted of cisplatin, Adriamycin, and cyclophosphamide; cisplatin, vinblastine, and bleomycin; and cisplatin, vindesin, and mitomycin, respectively. MBL were defined morphologically as having abundant pale cytoplasm with distinct cell borders and small nucleus. Immunohistochemistry revealed a B-cell nature of these cells, i.e., CD20+ and/or MB-1+ together with negative reactivity for antibodies for T lymphocytes (CD43, CD45RO, OPD4) and macrophages (KP-1, PGM-1). Monocytoid cells in two cases showed a positive reactivity for CD43 together with CD20. The occurrence rate of MBL in patients with ovarian, lung, and testicular cancer receiving and not receiving chemotherapy was 67% (2/3) and 10% (1/10), 59% (13/22) and 75% (6/8), and 43% (3/7) and 9% (1/11), respectively. The occurrence rate in the total patients receiving chemotherapy (56%) was significantly higher than for those not receiving chemotherapy (28%) (P < 0.05). These findings suggest that chemotherapy-induced depressed immune function is causative for the occurrence of MBL in the lymph nodes. MBL might be found more frequently in nodes from patients who have received chemotherapy in certain settings.

Adult

Malignant lymphoma of the adrenal gland: its possible correlation with the Epstein-Barr virus.

Initial manifestation of malignant lymphoma in the adrenal gland is a rare event, and clinical and pathologic features are not fully understood. We conducted a nationwide study in Japan, and 20 patients with malignant lymphoma that showed initial and main manifestation in the adrenal gland were identified. Clinical and pathologic findings were summarized. In addition, the presence of the Epstein-Barr virus (EBV) genome in the tumor cells was examined by using polymerase chain reaction (PCR) and in situ hybridization (ISH), together with the immunohistochemical evaluation of the expression of latent membrane protein-1 (LMP-1). There were 13 men and seven women; their ages at admission ranged from 40 to 87 years (median, 65 yr). Fever, anemia, and elevation of lactic dehydrogenase levels were the common presenting findings. One patient had acquired immunodeficiency syndrome. Adrenal tumors were bilateral in 15 patients and unilateral (all in the left site) in five. Prognosis was very poor; all but two patients died within 1 year after admission. Histologically diffuse large cell type was the commonest type (14 specimens). Immunohistologically, 16 specimens were B-cell type, and one was T-cell type. Another three specimens showing no positive reaction for any antibodies were also judged as B-cell type on purely morphologic grounds. Prominent intravascular proliferation of tumor cells was found in five patients. PCR for EBV genomes gave positive results in five patients; the virus was subtyped as A in three patients and as B in two. The ISH provided positive signals in nine samples, including all five specimens positive for PCR. Four of the nine cases with detectable EBV by PCR and/or ISH expressed LMP-1. The present study shows that adrenal lymphoma is EBV associated and has a B-cell phenotype.

Adrenal Gland Neoplasms

[Sinus venosus atrial septal defect: report of two cases with successful repair by the Vargas' procedure].

Two cases of sinus venosus atrial septal defect with partial anomalous of right upper pulmonary venous drainage into superior vena cava treated by the Vargas' procedure were reported. These patients were 5 and 6 years old. Post operative courses were uneventful, and results of postoperative hemodynamic and clinical evaluation were encouraging. The Vargas' procedure is useful method for a reconstraction of the anomaly in childhood because of use of the autologus tissues. Though long-term fate of this procedure is still uncertain. Then, we consider that a long-term follow up is necessary.

Cardiac Surgical Procedures

Use of immunohistochemical procedures in diagnosing angiosarcoma. Evaluation of 98 cases.

BACKGROUND: Differential diagnosis of angiosarcoma, predominantly showing a non- or poorly vasoformative proliferation from other types of sarcomas, poorly differentiated carcinomas, and amelanotic melanoma, is often problematic. METHODS: The use of antibodies directed against Factor VIII-related antigen (FVIIIRA), Ulex europaeus lectin type 1 (UEA-1), CD31, and vascular endothelial growth factor (VEGF) in the diagnosis of angiosarcoma was examined in 98 cases of autopsy-proven angiosarcoma diagnosed during 1974-1990 in a survey of 178 Japanese hospitals. Reactivity of angiosarcoma cells for epithelial membrane antigen, cytokeratin, and melanoma cell antigen (HMB45) also was examined. RESULTS: Histologic specimens were formed exclusively by vasoformative areas in 32 cases and combined vasoformative and varying extents of non- or poorly vasoformative areas in another 66 cases. In vasoformative areas, the proliferating cells showed a diffuse positive reaction in the cytoplasm and/or cell surface for anti-FVII-IRA in 82 (84%) of 98 cases, for anti-CD31 in 78 (80%), and for UEA-1 in 69 (70%). In non- or poorly vasoformative areas, the positivity rate for FVIIIRA, CD31, and UEA-1 was 29%, 62%, and 46%, respectively. A positive reaction was found for either one of three endothelial markers in the non- or poorly vasoformative areas of 57 cases (86%). Epithelial membrane antigen and anticytokeratin antibody were positive in 4 and 11 cases, respectively, in the vasoformative areas and in 3 and 14 cases, respectively, in non- or poorly vasoformative areas with a simultaneous positive reaction for either one of three endothelial cell markers. None of the proliferating cells showed a positive reactivity for HMB45. The positivity rates of the angiosarcoma cells for each marker were different according to the primary tumor sites. The angiosarcoma cells in non- or poorly vasoformative areas showed the lowest positivity rate for anti-FVIIIRA in the heart (9%) and for anti-CD31 in the extremities (17%) and the highest positivity rate for anticytokeratin in the trunk (60%). Ulex europaeus lectin type 1 had almost the same reactivity rate (30-56%) in every organ. Angiosarcoma cells in 13 (36%) of 36 biopsy specimens and 8 (14%) of 56 autopsy specimens were positive for the anti-VEGF antibody. CONCLUSION: These findings suggest that the combined use of endothelial cell markers including FVIIIRA, UEA-1, and CD31 is useful in the diagnosis of angiosarcoma, especially in cases exclusively with a non- or poorly vasoformative pattern.

Adolescent

Antinociceptive effects of the selective non-peptidic delta-opioid receptor agonist TAN-67 in diabetic mice.

The antinociceptive potencies of 2-methyl-4 alpha alpha-(3-hydroxyphenyl)-1,2,3,4,4a,5,12,12 alpha alpha-octahydro-quinolino[2,3,3-g]isoquinoline (TAN-67), a non-peptidic delta-opioid receptor agonist, were examined using the acetic acid abdominal constriction test and the tail-flick test in diabetic mice. TAN-67, at doses of 3-100 mg/kg, s.c. [corrected], produced a marked and dose-dependent inhibition of the number of acetic acid-induced abdominal constrictions in both non-diabetic and diabetic mice. The antinociceptive effect of TAN-67 in the acetic acid abdominal constriction test in diabetic mice was greater than that in non-diabetic mice. Indeed, the ED50 (95% confidence limits) value of TAN-67 for the inhibition of acetic acid-induced abdominal constrictions in diabetic mice (6.0 (3.5-10.5) mg/kg) was significantly lower than that in non-diabetic mice (31.4 (14.2-69.4) mg/kg). The antinociceptive effect of TAN-67 was not antagonized by pretreatment with either beta-funaltrexamine, a selective mu-opioid receptor antagonist, or nor-binaltorphimine, a selective kappa-opioid receptor antagonist. When 7-benzylidenenaltrexone (0.3 mg/kg, s.c.), a selective delta 1-opioid receptor antagonist, was administered 10 min before treatment with TAN-67, the antinociceptive effect of TAN-67 was significantly antagonized. However, naltriben, a selective delta 2-opioid receptor antagonist, had no significant effect on the antinociceptive effect of TAN-67. Furthermore, in the tail-flick test, TAN-67 at doses of 3-30 mg/kg, s.c. [corrected], also produced a marked and dose-dependent antinociceptive effect in diabetic mice, but not in non-diabetic mice. In conclusion, TAN-67 produced an antinociceptive effect through the activation of delta 1-opioid receptors. Furthermore, the results of this study support our hypothesis that mice with diabetes are selectively hyperresponsive to delta 1-opioid receptor-mediated antinociception.

Analgesics

Angiosarcoma in Japan. A review of 99 cases.

BACKGROUND: Angiosarcoma is rare, and information about its clinical features are limited. Therefore, a large scale study of angiosarcoma was performed in Japan. METHODS: Through a nationwide Japanese study, 99 cases of angiosarcoma were collected and their clinicopathologic findings were summarized relative to predisposing risk factors. RESULTS: The patient age at diagnosis was 3-92 years, (mean, 62 years), with a two to one male to female ratio. The head and face were the most common primary site (29 cases); other sites were liver (17); trunk (13): pleural cavity (6), chest wall (2), abdominal wall (2), buttock (2), inguinal region (1); heart (12); and extremities (7). The proven predisposing risk factors included chronic pyothorax for angiosarcoma in the pleural cavity (six), thorotrast in the liver (five), radiotherapy to the abdominal wall and buttock (four), and chronic limb edema of the forearm (one). Irrespective of primary sites, the majority of cases had metastases to lung in 72 cases, bone in 42, liver in 36, regional lymph nodes in 30, and adrenal gland in 24. The 2-year survival rate was 17%. CONCLUSIONS: This study describes a different etiology in the development of angiosarcoma in patients from Japan compared with that of patients from Western countries, though the frequency of angiosarcoma among all soft-tissue sarcomas was similar in both areas. In Japan, chronic pyothorax, radiotherapy, and thorotrast proved to be distinctive causative factors of angiosarcoma.

Adolescent

Polymorphic reticulosis is a neoplasm of large granular lymphocytes with CD3+ phenotype.

BACKGROUND: Polymorphic reticulosis, a type of lethal midline granuloma (LMG), has been referred to as nasal T-cell lymphoma (NTL) because of its proliferating cells' positive reactivity to anti-T-lymphocyte antibodies. Recently, several studies have suggested that proliferating cells in NTL may be natural killer (NK) in nature. NK cells and human nonmajor histocompatibility-restricted cytotoxic T-lymphocytes have the morphology of large granular lymphocytes (LGL) (i.e., a high cytoplasmic:nuclear ratio and cytoplasmic granules). Whether NTL-LMG possesses an LGL morphology is examined in this study. METHODS: Two lymph node smears, peripheral blood showing a leukemic picture, and an electron microscope (EM) examination of a cutaneous lesion, respectively, were obtained from four patients with NTL-LMG. Immunohistochemical examination of the proliferating cells and of the Epstein-Barr virus (EBV) genome by both polymerase chain reaction and in situ hybridization also were performed. RESULTS: All patients presented with necrotic and granulomatous lesions in the upper respiratory tract. Histology showed polymorphous cellular infiltrates containing large atypical cells with positive reaction to CD3 (three patients), CD43 (two patients), CD45RO (two patients), and OPD4 (one patient). Imprint smears revealed azurophilic large membrane-delimited granules in an ample cytoplasm, which was confirmed by EM. The presence of the EBV genome in the tumor cells was observed in one patient. CONCLUSION: The current findings showed that NTL-LMG or polymorphic reticulosis is a proliferation of LGL with a CD3+ phenotype.

Adult

Efficient induction of chromosome-type aberrations by topoisomerase II inhibitors closely associated with stabilization of the cleavable complex in cultured fibroblastic cells.

Eukaryotic topoisomerase II (Topo-II) inhibitors such as etoposide, adriamycin and mitoxantrone, which commonly stabilize the cleavable complex of the enzyme and DNA, have been found to efficiently induce chromosome-type aberrations (mainly breaks and exchanges) in cultured Chinese hamster lung fibroblastic cells (CHL cells). To clarify whether the induction of chromosome-type aberrations is mediated by stabilization of the cleavable complex, the present study investigated (1) the correlation between the induction of chromosome-type aberrations and the amount of cleavable complex formed; and (2) the ATP dependence of the Topo-II inhibitor-induced chromosome-type aberrations due to the ATP requirement of cleavable complex formation by Topo-II. First, in cells treated with the Topo-II inhibitors, (etoposide, adriamycin) and aclarubicin, an antagonist of the inhibitor of cleavable complex formation, the frequency of chromosome-type aberrations decreased dose-dependently with aclarubicin, in contrast to an increase of chromatid-type aberrations. The formation of the cleavable complex was further established by a proteinase K/SDS precipitation assay for cleaved double-strand DNA in a cell-free system and in CHL cells. Results from both experiments showed that aclarubicin caused a dose-dependent suppression of the accumulation of the cleavable complex induced by etoposide, which corresponded particularly well to the reduction of chromosome-type aberrations in etoposide-treated cells. In ATP-depleted cells simultaneously treated with etoposide and dinitrophenol (DNP), chromosome-type aberrations were reduced as compared with DNP-untreated cells, in contrast to an increase of chromatid exchanges in the cells. This means that etoposide-induced chromosome-type aberrations in ATP-depleted cells may be attributable to incompleteness of Topo-II activities to form DNA double-strand breaks. The present findings indicate that the stabilization of the cleavable complex on Topo-II is closely associated with the induction of chromosome-type aberrations.

2,4-Dinitrophenol

Fatigue resistance of composite restorations: effect of filler content.

OBJECTIVES: The purpose of this study was to evaluate the effects of filler level on the fatigue impact resistance of resin composite. METHODS: A series of experimental composite materials was prepared by incorporating a silanized quartz filler (3-5 microns in size) into a light-cured resin matrix of Bis-GMA/TEGDMA. The filler contents in the experimental composites varied from 40 to 85 wt%. The composites were placed in standardized Class I cavities prepared in bovine teeth. The specimens were stressed with a repetitive impact load (1.6 x 10(2) joule) with loading cycles ranging from 50,000 to 150,000 times. The cracks induced by cyclic loading were observed on the sectioned surfaces of the tested specimens. RESULTS: The composites with considerably low or high filler content (< 60% or > 80% by weight) were significantly low in fatigue resistance. The results revealed that an inverse linear relationship tended to exist between filler level and fatigue resistance of the composite materials beyond a certain level of filler content. SIGNIFICANCE: Increased filler level does not necessarily improve the fatigue resistance of a resin composite as determined by applying a repetitive impact load.

Animals

Enhancing effects of diphenyl dimethyl dicarboxylate on serum antibody production in BALB/c mice.

The effects of diphenyl dimethyl dicarboxylate (PMC) on serum antibody production were investigated in BALB/c mice. PMC (3 and 6 mg/kg/d, respectively) was orally administered to the mice for 14 consecutive days. The effects on antibody production were assessed by enzyme-linked immunosorbant assay (ELISA) of immunoglobulin (Ig) subset levels in serum, collected at week 2 from mice with or without immunization by an i.p. injection of 0.1 mg ovalbumin (OVA) in complete Freund's adjuvant (CFA) at week 1 after the first oral administration of PMC. PMC showed a significant enhancement of the levels of total serum IgG, IgG1, IgG2a and IgA without the immunization, while total IgE levels were not affected. When mice were immunized with OVA after the oral administration of PMC, moreover, a marked stimulation of antibody production was observed in mice fed 6 mg/kg/d PMC, hardly accompanied with increase of IgE levels. In these mice, additionally, PMC significantly elevated anti-OVA IgG (including both IgG1 and IgG2a mediated by different T-helper cells) levels. These findings indicate that PMC enhances antibody production in mice with therapeutic concentrations that have shown great promise in the treatment of chronic hepatitis virus of type B.

Animals

Oral tolerance to ovalbumin in mice as a model for detecting modulators of the immunologic tolerance to a specific antigen.

Oral tolerance is thought to have a role in preventing allergic responses and immune-mediated diseases. Modulation of this tolerance by drugs and chemicals can cause or suppress them. An improved model of oral tolerance to ovalbumin (OVA) in mice was developed to detect modulators of the tolerance and to apply it to selected immunomodulating substances, cyclophosphamide (CP), Escherichia coli lipopolysaccharide (LPS) and cadmium chloride (Cd). Male C3H/HeN mice given an oral administration of 20 mg OVA were immunized 7 d later with an i.p. injection of 0.1 mg OVA in complete Freund's adjuvant. Effects of oral OVA and agents on systemic immunity were assessed by enzyme-linked immunosorbent assay (ELISA) of immunoglobulin (Ig) levels in serum collected 7 or 14 d after immunization. Oral tolerance was adequately induced on day 7 after immunization and was more effective in C3H/HeN mice than in BALB/c mice. It was primarily associated with the decreased serum levels of anti-OVA IgG (including both IgG1 and IgG2a subclasses regulated differently by T-helper subpopulations, Th2 and Th1 cells, respectively). The C3H model of oral tolerance was further examined to detect modulators of the tolerance. An i.p. injection of CP prior to oral OVA, or 5 consecutive daily oral administrations of LPS after oral OVA elevated or reduced serum levels of anti-OVA IgG in C3H mice hyposensitized by the oral OVA, respectively. Concerning IgG subclasses, CP restored anti-OVA IgG2a but not IgG1 levels, while LPS caused greater suppression of both anti-OVA IgG1 and IgG2a levels. Oral administrations of Cd for 5 d after oral OVA also suppressed anti-OVA IgG1 levels further.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic

Immunologic type of thyroid lymphoma in an adult T-cell leukemia endemic area in Japan.

Our previous study showed that thyroid non-Hodgkin's lymphoma (TL) in an adult T-cell leukemia/lymphoma (ATL) non-endemic area were exclusively B-cell derived. The present study was carried out to examine whether TL in an ATL endemic area are also exclusively of B-cell type. Eight cases with TL admitted to the hospital situated in an ATL endemic area were studied: they were all female with an age range from 50 to 75 (median 67) years. Histologically four of the eight cases showed a follicular pattern. Immunophenotypic study revealed all but one case to be of B-cell nature: CD3-, 4-, 8-, 20+, 22+, 45RA+, 45RO-, L22-, L24+/-, L28+. Neoplastic cells in one case with the histology of diffuse large cell lymphoma showed a CD3+, 4+, 8-, 20-, 22-, 45RA-, 45RO+/-, L22-, L24-, L28-, indicating a helper T-cell phenotype. Genotypic study showed rearrangement of T-cell beta-chain receptor in this case. This case also had antibodies against HTLV-1 in the serum. This case shows that it is also possible to develop T-cell TL in an endemic ATL area.

Aged

Sporadic activation of Epstein-Barr virus in thyroid lymphoma.

The causal role of Epstein-Barr virus (EBV) in the development of B-cell lymphoma, especially in immunocompromised individuals, has been suggested. The purpose of the present study was to evaluate an association of EBV with thyroid lymphoma (TL) and chronic lymphocytic thyroiditis (CLTH) which is known to play an important role in the development of TL. Thirty cases with TL and 28 with CLTH were studied for presence or absence of EBV genome in the lesions using the polymerase chain reaction (PCR) and the in situ hybridization method. EBV genomes were detected by PCR in one and two cases with CLTH and TL, respectively. Subtyping of EBV genome was possible in one TL case showing B-type in EBNA-2 coding region. In situ hybridization revealed positive signals in the nucleus of lymphoma cells, which also expressed latent membrane protein-1. The present findings indicate that activation of EBV in TL is not common.

Adolescent

Angiomatous lesions in the wall of chronic pyothorax.

Formation of massive hematoma in the cavity of chronic pyothorax (CP) has been described previously, but its mechanism remained unclear. In the present study of 99 cases, the vascular lesions in the wall of CP were examined by histological methods, including immunohistochemistry. The age of patients ranged from 42 to 80 years (mean 57 years), with a male to female ratio of 3.3. Histologically the CP wall was covered by a fibrin layer containing cellular debris and red blood cells. Directly beneath the fibrin layer, a fibrous layer of varied thickness was present that extended to the subserosal tissue or so-called fat plane defined by computed tomography. At the junctional region between the fibrin and fibrous layer, angiomatous lesions were observed in 33 cases (Group I). In the fibrin layer of this group, dilated vessels frequently bulged into the pleural cavity. In another two cases, closely packed large vessels with irregularly thickened walls resembled an arteriovenous fistula (Group II). In seven patients, histologic specimens showed a total necrosis. The remaining 57 cases without the findings in Groups I and II were categorized as Group III. These findings suggested that formation of angiomatous lesion preceed intrapleural bleeding, which occasionally progressed to form a massive hematoma.

Adult

Modification of mu-opioid agonist-induced locomotor activity and development of morphine dependence by diabetes.

We examined the locomotor-enhancing action of mu-opioid receptor agonists, such as morphine and [D-Ala2, N-MePhe4, Gly-ol5]enkephalin (DAMGO), and physical dependence on morphine in diabetic and nondiabetic mice. Morphine (5-20 mg/kg, s.c.) and DAMGO (1-4 nmol, i.c.v.) had a dose-dependent locomotor-enhancing effect in both nondiabetic and diabetic mice. The locomotor-enhancing effects of morphine and DAMGO were significantly less in diabetic mice than in nondiabetic mice, and were significantly reduced after pretreatment with either beta-funaltrexamine (20 mg/kg, s.c.), a selective mu-opioid receptor antagonist, or naloxonazine (35 mg/kg, s.c.), a selective mu1-opioid receptor antagonist. Both diabetic and nondiabetic mice were chronically treated with morphine (8-45 mg/kg, s.c.) for 5 days. During this treatment, neither diabetic nor nondiabetic mice showed any signs of toxicity. After morphine treatment, withdrawal was precipitated by injection of naloxone (0.3-10 mg/kg, s.c.). Several withdrawal signs, such as weight loss, diarrhea, ptosis, jumping and body shakes, were observed after naloxone challenge in morphine-dependent nondiabetic mice. Although morphine-dependent diabetic mice showed greater weight loss than nondiabetic mice, the incidence of jumping and body shakes after naloxone challenge in diabetic mice were lower than that in nondiabetic mice. These results suggest that diabetic mice are selectively hyporesponsive to mu1-opioid receptor-mediated locomotor enhancement. Furthermore, diabetes may affect mu1-opioid receptor-mediated naloxone-precipitated signs of withdrawal from physical dependence on morphine.

Animals