Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy

We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM.     

Effect of systemic zinc administration on delayed neuronal death in the gerbil hippocampus

The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca²⁺-Mg²⁺ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl₂ (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n=6) or twice at 24 and 48 h before ischemia (subacute group; n=14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity.     

Alteration of second-messenger ligand binding following 2-hr hemispheric ischemia in the gerbil brain.

The alterations of second-messenger ligand binding and cerebral blood flow (CBF) were evaluated in the gerbil brain after 2-h unilateral common carotid artery occlusion. [3H]Forskolin (FK) and [3H]phorbol-12,13-dibutyrate (PDBu) were used as specific ligands for adenylate cyclase (AC) and protein kinase C (PKC) activity estimation, respectively. CBF was determined at the end of the experiment by the [14C]iodoantipyrine method. A quantitative autoradiographic method permitted simultaneous measurement of the three parameters in the same brain. The levels in the caudate-putamen, globus pallidus, and hippocampus were analyzed. The animals were divided into three groups: Group 1 with severe ischemia (CBF in the lateral nuclei of the thalamus (CBFt) less than 50 ml/100 g/min), Group 2 with mild ischemia (CBFt greater than or equal to 50 ml/100 g/min), and the Sham Group. The PDBu binding revealed a statistically significant increase in the caudate-putamen, lateral nuclei of the thalamus and hippocampus (CA1 and CA3 regions and dentate gyrus) on the ischemic side in Group 1 as compared to that in Group 2 and the Sham Group. In contrast, the FK binding did not show any significant changes in any of the regions. These data and our previous findings for 6-h ischemia suggest that (1) PKC translocation to the cell membrane may occur at the early ischemic phase in particular regions including the caudate-putamen, lateral nuclei of the thalamus and hippocampus, with the translocated PKC gradually diminishing during the subsequent ischemic period; and (2) the suppression of the AC system observed in 6-h ischemia may not appear in the early ischemic phase.     

Effect of (2"R)-4'-O-tetrahydropyranyladriamycin, a new antitumor antibiotic, on the cardiac function of hamsters

Cardiovascular effects of (2'R)-4'-O-tetrahydropylanyladriamycin X HCl (THP) and doxorubicin (adriamycin, ADM) were studied in hamsters. In experiments to observe acute effects, THP was administered intravenously at a dose of 12.5, 25.0 or 50.0 mg/kg, and ADM at 1.56, 3.13 or 6.25 mg/kg was given to different subjects. The THP caused slight ECG alterations at a dose of 12.5 mg/kg. At a dose of 25.0 mg/kg or 50.0 mg/kg, THP caused moderate to remarkable alterations in ECG like a widening of PR and PRc interval, A-V block, ST segment depression and T wave flattening. The ADM caused moderate to remarkable alterations in ECG at a dose of 3.13 mg/kg or 6.25 mg/kg, including arrhythmia, bradycardia, A-V block, ST segment changes and T wave flattening. These changes caused by THP and ADM recovered within 5 approximately 10 minutes after injection. Alterations in the ultrastructure of the myocardium caused by THP at a dose of 50.0 mg/kg included some cells with slight changes like swelling of mitochondria, focal intracellular edema, and enlargement of myofibrils. The ADM, at a dose of 3.13 mg/kg, induced severer swelling of mitochondria than THP, dilatation of sarcoplasmic reticulum, intracellular edema, and disorganization of myofilaments. At a dose of 6.25 mg/kg of ADM, these changes became more pronounced. In experiments to observe subacute effects, hamsters were treated with THP or ADM by daily intraperitoneal injections for 15 consecutive days, and then allowed to be recovered for 15 days. Dose levels of THP or ADM were 0.125, 0.25, 0.5 and 1.0 mg/kg. General toxicity, ECG, hematological and blood biochemical analysis, and electron microscopic examination were studied. In the ECG study, THP-treated hamsters showed a reversible elevation of R wave amplitude at a daily dose of 0.5 mg/kg. Widening of PR and PRc interval, elevation of R and S wave amplitude, and reduction of T wave amplitude were observed at a daily dose of 1.0 mg/kg of THP. Hamsters treated with ADM showed increase of heart rate, reduction of T wave amplitude, and shortening of PR and PRc interval at a daily dose of 0.5 mg/kg. Severe changes were observed at a daily dose of 1.0 mg/kg of ADM including an increase of heart rate, elevation of R wave amplitude, reduction of S and T wave amplitude, and shortening of QT interval. The electron microscopic examination revealed that THP-treated hamsters showed separation of intercalated discs, formation of myelin structure, and dilatation of T-tubules at a daily dose of 1.0 mg/kg. Similar changes were caused by ADM at a daily dose of 0.25 to 1.0 mg/kg.(ABSTRACT TRUNCATED AT 400 WORDS)     

Cyclic tensile stretch load and oxidized low density lipoprotein synergistically induce lectin-like oxidized ldl receptor-1 in cultured bovine chondrocytes, resulting in decreased cell viability and proteoglycan synthesis.

Mechanical stimulation is known to be an essential factor in the regulation of cartilage metabolism. We tested the hypothesis that expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) can be modulated by cyclic tensile stretch load in chondrocytes. Cyclic loading of repeated stretch stress at 10 cycles per minute with 10 kPa of stress for 6 h induced expression of LOX-1 to 2.6 times control in cultured bovine articular chondrocytes, equivalent to the addition of 10 microg/mL oxidized low density lipoprotein (ox-LDL) (2.4 times control). Application of the cyclic load to the chondrocytes along with 10 microg/mL ox-LDL resulted in synergistically increased LOX-1 expression to 6.3 times control. Individual application of cyclic loading and 10 microg/mL ox-LDL significantly suppressed chondrocytes viability (84.6% +/- 3.4% and 80.9% +/- 3.2% of control at 24 h, respectively; n = 3; p < 0.05) and proteoglycan synthesis [81.0% +/- 7.1% and 85.7% +/- 5.2% of control at 24 h, respectively; p < 0.05 when compared with 94.6% +/- 4.6% for native-LDL (n = 3)]. Cyclic loading and 10 microg/mL ox-LDL synergistically affected cell viability and proteoglycan synthesis, which were significantly suppressed to 45.6% +/- 4.9% and 48.7% +/- 6.7% of control at 24 h, respectively (n = 3; p < 0.01 when compared with individual application of cyclic loading or 10 microg/mL ox-LDL). In this study, we demonstrated synergistic effects of cyclic tensile stretch load and ox-LDL on cell viability and proteoglycan synthesis in chondrocytes, which may be mediated through enhanced expression of LOX-1 and which has important implications in the progression of cartilage degeneration in osteoarthritis.     

Jejunal carcinoma with adenoma —Report of a case and review of the Japanese literature—

A rare case of jejunal carcinoma coexisting with adenoma, situated 120 cm distal to the ligament of Treitz in a 53 year old male, is reported herein. We also review cases of adenoma and carcinoma in the jejunum and ileum from the Japanese literature, and discuss the histogenesis of carcinoma of the jejunum and ileum.     

Immunological Detection and Quantitation of DNA Adducts Formed by 4-Aminoazobenzene Species in vivo

Antibodies to 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and 2-methoxy-4-aminoazobenzene (2-MeO-AAB) DNA adducts were raised in rabbits against in vitro-adducted DNA samples. The enzyme-linked immunosorbent assay (ELISA) was used to determine the sensitivity and specificity of these antibodies. They proved highly specific for the modified DNA used as the immunogen, but cross-reacted with each other. Moreover, they showed cross reactivity with DNA modified by 4-( o -tolylazo)- o -toluidine, but not by other carcinogens, such as 4-aminobiphenyl or 4-nitroquinoline 1-oxide. The 50% inhibition level of antibody binding in the competitive ELISA was at 10–20 fmol of modified base per assay (equivalent to 1–2 adducts per 10⁶ bases). Immunohistochemical staining indicated that these antibodies bind specifically to nuclear components of the liver in rats given either 3-MeO-AAB or 2-MeO-AAB at the dose of 50 mg/kg body weight.     

Tumor dissemination during laparoscopic cholecystectomy for gallbladder carcinoma

Surgical Endoscopy -     

Time course of superoxide generation by leukocytes—The MCLA chemiluminescence system

This study was performed to examine the pattern of Superoxide (O ₂ ^– ·) generation from leukocytes using the O ₂ ^– · specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O ₂ ^– · generation by leukocytes. The time course of O ₂ ^– · generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O ₂ ^– · for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O ₂ ^– · generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O ₂ ^– · much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O ₂ ^– · generation by leukocytes.