[Emergent surgical treatment of type A acute aortic dissection in an elderly patient]

An 86-year-old man with severe chest pain and shock was transferred to our hospital. Computed tomography revealed type A aortic dissection with cardiac tamponade. He needed intubation and closed chest massage preoperatively. At operation, intrapericardial space was filled with clotted blood and rupture of the ascending aorta was confirmed. He underwent a successful emergency graft replacement of the ascending aorta. Postoperative course was uneventful except for mild hemianopsia due to cerebral infarction. He had recovered to be able to walk and is doing well.

Phospholipase Cbeta4 and protein kinase Calpha and/or protein kinase CbetaI are involved in the induction of long term depression in cerebellar Purkinje cells

Activation of the type-1 metabotropic glutamate receptor (mGluR1) signaling pathway in the cerebellum involves activation of phospholipase C (PLC) and protein kinase C (PKC) for the induction of cerebellar long term depression (LTD). The PLC and PKC isoforms that are involved in LTD remain unclear, however. One previous study found no change in LTD in PKCgamma-deficient mice, thus, in the present study, we examined cerebellar LTD in PLCbeta4-deficient mice. Immunohistochemical and Western blot analyses of cerebellum from wild-type mice revealed that PLCbeta1 was expressed weakly and uniformly, PLCbeta2 was not detected, PLCbeta3 was expressed predominantly in caudal cerebellum (lobes 7-10), and PLCbeta4 was expressed uniformly throughout. In PLCbeta4-deficient mice, expression of total PLCbeta, the mGluR1-mediated Ca(2+) response, and LTD induction were greatly reduced in rostral cerebellum (lobes 1-6). Furthermore, we used immunohistochemistry to localize PKCalpha, -betaI, -betaII, and -gamma in mouse cerebellar Purkinje cells during LTD induction. Both PKCalpha and PKCbetaI were found to be translocated to the plasmamembrane under these conditions. Taken together, these results suggest that mGluR1-mediated activation of PLCbeta4 in rostral cerebellar Purkinje cells induced LTD via PKCalpha and/or PKCbetaI.

Sequence-dependent antitumor efficacy of combination chemotherapy with nedaplatin, a newly developed platinum, and paclitaxel

We evaluated the sequence dependency of antitumor efficacy and toxicity in combination therapy of nedaplatin (NDP) with paclitaxel (TXL) against Lewis lung carcinoma. The sequential administration of NDP prior to TXL (NT therapy) resulted in severe body weight loss followed by frequent toxic death of mice. In contrast, the sequential dosing of TXL prior to NDP (TN therapy) resulted in synergistically enhanced inhibition of tumor growth with less toxicity compared with the NT therapy. Comparing the antitumor activity of NDP plus TXL with that of cisplatin (CDDP) plus TXL or carboplatin (CBDCA) plus TXL, the combination effect of NDP plus TXL was significantly higher than that of CDDP plus TXL or CBDCA plus TXL. These results indicate that the TN therapy may have significant potential in clinical use.

Rudimentary TCR signaling triggers default IL-10 secretion by human Th1 cells

Understanding the process of inducing T cell activation has been hampered by the complex interactions between APC and inflammatory Th1 cells. To dissociate Ag-specific signaling through the TCR from costimulatory signaling, rTCR ligands (RTL) containing the alpha1 and beta1 domains of HLA-DR2b (DRA*0101:DRB1*1501) covalently linked with either the myelin basic protein peptide 85-99 (RTL303) or CABL-b3a2 (RTL311) peptides were constructed to provide a minimal ligand for peptide-specific TCRs. When incubated with peptide-specific Th1 cell clones in the absence of APC or costimulatory molecules, only the cognate RTL induced partial activation through the TCR. This partial activation included rapid TCR zeta-chain phosphorylation, calcium mobilization, and reduced extracellular signal-related kinase activity, as well as IL-10 production, but not proliferation or other obvious phenotypic changes. On restimulation with APC/peptide, the RTL-pretreated Th1 clones had reduced proliferation and secreted less IFN-gamma; IL-10 production persisted. These findings reveal for the first time the rudimentary signaling pattern delivered by initial engagement of the external TCR interface, which is further supplemented by coactivation molecules. Activation with RTLs provides a novel strategy for generating autoantigen-specific bystander suppression useful for treatment of complex autoimmune diseases.

Impaired delay but normal trace eyeblink conditioning in PLCbeta4 mutant mice

To elucidate the functional role of phospholipase Cbeta4 (PLCbeta4), which is highly expressed in the Purkinje cells of the rostral cerebellum, cerebellar long-term depression (LTD) and delay and trace eyeblink conditioning were investigated in PLCbeta4-deficient mice. Rostral cerebellar LTD and delay eyeblink conditioning were severely impaired, whereas trace eyeblink conditioning was not. These results indicate that PLCbeta4 is essential for LTD in the rostral cerebellum and delay conditioning, but not trace conditioning. Rostral cerebellar LTD may be required as a neural substrate for delay conditioning, but is not required for trace conditioning.

Bacterial lipopolysaccharide induces transforming growth factor beta and hepatocyte growth factor through toll-like receptor 2 in cultured human colon cancer cells

This study examined, in human cancer lines, the pattern of cytokine production stimulated by lipopolysaccharide (LPS), a major component of outer surface of gram-negative bacteria, and characterized the expression pattern of CD14, cell surface LPS receptor antigen, and toll-like receptors (TLRs), which appear to be key regulators of the innate immune response system. Two colon cancer cell lines (DLD and LoVo), a hepatocellular carcinoma cell line and a myelomonocytic cell line were incubated with LPS for 0-72 h, and transforming growth factor (TGF) beta1 and beta2, hepatocyte growth factor (HGF) and interleukins 6, 8 and 15 were assayed. The only changes induced by incubation with LPS were significant increases in TGFbeta1 production at 12 h, and in HGF production at 72 h, in LPS-stimulated DLD cells, and significant increases in TGFbeta2 production after 12 h and in HGF after 72 h in LoVo cells. Using reverse transcriptase-polymerase chain reaction analysis, expression of CD14 and TLR-2 mRNA was detected in DLD and LoVo cells, and expression of TLR-4 mRNA was detected in PLC/PRF/5 and KG-1 cells. These results suggest that LPS induces TGFbeta and HGF production mediated by CD14/TLR-2 in cultured human colon cancer cell lines.

Neural coding mechanisms underlying perceived roughness of finely textured surfaces

Combined psychophysical and neurophysiological studies have shown that the perceived roughness of surfaces with element spacings of >1 mm is based on spatial variation in the firing rates of slowly adapting type 1 (SA1) afferents (mean absolute difference in firing rates between SA1 afferents with receptive fields separated by approximately 2 mm). The question addressed here is whether this mechanism accounts for the perceived roughness of surfaces with element spacings of <1 mm. Twenty triangular and trapezoidal gratings plus a smooth surface were used as stimulus patterns [spatial periods, 0.1-2.0 mm; groove widths (GWs), 0.1-2.0 mm; and ridge widths (RWs), 0-1.0 mm]. In the human psychophysical studies, we found that the following equation described the mean roughness magnitude estimates of the subjects accurately (0.99 correlation): 0.2 + 1.6GW - 0.5RW - 0.25GW(2). In the neurophysiological studies, these surfaces were scanned across the receptive fields of SA1, rapidly adapting, and Pacinian (PC) afferents, innervating the glabrous skin of anesthetized macaque monkeys. SA1 spatial variation was highly correlated (0.97) with human roughness judgments. There was no consistent relationship between PC responses and roughness judgments; PC afferents responded strongly and almost equally to all of the patterns. Spatial variation in SA1 firing rates is the only neural code that accounts for the perceived roughness of surfaces with finely and coarsely spaced elements. When surface elements are widely spaced, the spatial variation in firing rates is determined primarily by the surface pattern; when the elements are finely spaced, the variation in firing rates between SA1 afferents is determined by stochastic variation in spike rates.

Inhibitory effects of cyclic AMP elevating agents on lipopolysaccharide (LPS)-induced microvascular permeability change in mouse skin

Anti-inflammatory effects of cyclic AMP elevating agents were examined in a mouse model of lipopolysaccharide (LPS)-induced microvascular permeability change. Vascular permeability on the back skin was measured by the local accumulation of Pontamine sky blue (PSB) after subcutaneous injection of LPS (400 microg site-1) from Salmonella typhimurium. Dye leakage in the skin was significantly increased 2 h after injection of LPS. This LPS-induced dye leakage was suppressed by phosphodiesterase inhibitors, including pentoxifylline (160 mg kg-1), milrinone (5 - 10 mg kg-1), rolipram (0.5 - 10 mg kg-1) and zaprinast (5 - 10 mg kg-1). The dye leakage was also inhibited by beta-adrenoceptor agonists, including isoproterenol (0.5 - 5 mg kg-1) and salbutamol (0.05 - 5 mg kg-1), an adenylate cyclase activator, forskolin (5 mg kg-1), and a cell permeable cyclic AMP analogue, 8-bromo-cyclic AMP (8-Br-cAMP, 10 mg kg-1). LPS caused a transient increase in serum TNF-alpha level peaking at 1 h after the injection. This increase in serum TNF-alpha was completely blocked by a pretreatment with pentoxifylline (160 mg kg-1), milrinone (5 mg kg-1), rolipram (1 mg kg-1), zaprinast (10 mg kg-1), salbutamol (0.5 mg kg-1), forskolin (1 mg kg-1) and 8-Br-cAMP (10 mg kg-1). LPS caused an increase in serum IL-1alpha level peaking at 3 h after injection. This increase in serum IL-1alpha was not significantly suppressed by the cyclic AMP elevating agents. Our study suggests that cyclic AMP elevating agents attenuate LPS-induced microvascular permeability change by suppressing TNF-alpha up regulation.

Efficacy of early piston-type high-frequency oscillatory ventilation in infants with respiratory distress syndrome

We investigated whether the combination of surfactant replacement therapy and early application of high-frequency oscillatory ventilation (HFOV) was more effective in patients with respiratory distress syndrome (RDS) than late application of HFOV and conventional mechanical ventilation (CMV). To determine this, we retrospectively reviewed the cases of 126 neonates with RDS who received surfactant replacement therapy within 4 hr after birth. Patients were grouped into those who received HFOV immediately after birth (HFOV group), those who initially were ventilated by CMV and subsequently received HFOV (CMV/HFOV group), and those who did not receive HFOV (CMV group). Changes in respiratory system compliance (Crs), arterial-alveolar oxygen gradient (a/ApO(2)), and mean airway pressure (MAP) were compared. Infants who received HFOV were less mature than those who received CMV. The a/ApO(2) measured immediately after birth before surfactant replacement therapy was significantly lower in the HFOV and CMV/HFOV group than in the CMV group. After 72 hr, the Crs in the HFOV group was higher than in any other group and was significantly higher than the CMV/HFOV group at 48 and 120 hr. These results suggest that initiating HFOV in combination with surfactant replacement therapy immediately after birth provides effective ventilatory support for infants with RDS.

Regulation of melatonin 1a receptor signaling and trafficking by asparagine-124

Melatonin is a pineal hormone that regulates seasonal reproduction and has been used to treat circadian rhythm disorders. The melatonin 1a receptor is a seven- transmembrane domain receptor that signals predominately via pertussis toxin-sensitive G-proteins. Point mutations were created at residue N124 in cytoplasmic domain II of the receptor and the mutant receptors were expressed in a neurohormonal cell line. The acidic N124D- and E-substituted receptors had high-affinity (125)I-melatonin binding and a subcellular localization similar to the neutral N124N wild-type receptor. Melatonin efficacy for the inhibition of cAMP by N124D and E mutations was significantly decreased. N124D and E mutations strongly compromised melatonin efficacy and potency for inhibition of K(+)-induced intracellular Ca(++) fluxes and eliminated control of spontaneous calcium fluxes. However, these substitutions did not appear to affect activation of Kir3 potassium channels. The hydrophobic N124L and N124A or basic N124K mutations failed to bind (125)I-melatonin and appeared to aggregate or traffic improperly. N124A and N124K receptors were retained in the Golgi. Therefore, mutants at N124 separated into two sets: the first bound (125)I-melatonin with high affinity and trafficked normally, but with reduced inhibitory coupling to adenylyl cyclase and Ca(++) channels. The second set lacked melatonin binding and exhibited severe trafficking defects. In summary, asparagine-124 controls melatonin receptor function as evidenced by changes in melatonin binding, control of cAMP levels, and regulation of ion channel activity. Asparagine-124 also has a unique structural effect controlling receptor distribution within the cell.

X-Ray Telescope Onboard Astro-E. II. Ground-Based X-Ray Characterization

X-ray characterization measurements of the x-ray telescope (XRT) onboard the Astro-E satellite were carried out at the Institute of Space and Astronautical Science (Japan) x-ray beam facility by means of a raster scan with a narrow x-ray pencil beam. The on-axis half-power diameter (HPD) was evaluated to be 1.8?-2.2?, irrespective of the x-ray energy. The on-axis effective areas of the XRTs for x-ray imaging spectrometers (XISs) were approximately 440, 320, 240, and 170 cm(2) at energies of 1.49, 4.51, 8.04, and 9.44 keV, respectively. Those of the x-ray spectrometer (XRS) were larger by 5-10%. The replication method introduced for reflector production significantly improved the imaging capability of the Advanced Satellite for Cosmology and Astrophyics (ASCA) XRT, whose HPD is ~3.6?. The increase in the effective area by a factor of 1.5-2.5, depending upon the x-ray energy, compared with that of the ASCA, was brought about by mechanical scale up and longer focal lengths. The off-axis HPDs were almost the same as those obtained on the optical axis. The field of view is defined as the off-axis angle at which the effective area becomes half of the on-axis value. The diameter of the field of view was ~19? at 1.49 keV, decreasing with increasing x-ray energy, and became ~13? at 9.44 keV. The intensity of stray light and the distribution of this kind of light on the focal plane were measured at the large off-axis angles 30? and 60?. In the entire XIS field of view (25.4 mm x 25.4 mm), the intensity of the stray light caused by a pointlike x-ray source became at most 1% of the same pointlike source that was on the optical axis.

Structure-activity relationships in the deacetylation of O-glucosides of N-hydroxy-N-arylacylamides by mammalian liver microsomes

Structure-activity relationships in the deacylation of O-glucosides of N-hydroxy-N-aryl-acylamides were investigated to provide insights into the metabolic activation of carcinogenic/mutagenic O-glycosides of N-hydroxy-N-arylacylamides. In the subcellular fractions obtained from porcine liver, the deacetylation activity toward O-glucoside of N-hydroxyacetanilide (GAc) was mainly localized in the microsomes. Both the 2-chloro (2ClGAc) and 2-methyl (2MeGAc) derivatives of GAc were not deacetylated by the microsomes. Other compounds having either 3- or 4-substituent (chloro or methyl), however, were deacetylated and showed higher V(max)/K(m) values than that of GAc. 4-Methyl derivative (4MeGAc) was shown to competitively inhibit the deacetylation activity toward GAc, and the K(i) value of 4MeGAc was comparable with its K(m) value obtained in the microsome-catalyzed deacetylation. These apparent K(m) values were shown to correspond to their lipophilicities estimated from retention times on high-performance liquid chromatography (HPLC). As for the effect of acyl groups, the order of V(max)/K(m) values was N-propionyl derivative (GPr)>GAc>N-butyryl derivative (GBu). From the optimized structures and energy levels of the frontier orbitals of these compounds, calculated by the semi-empirical AM1 method, the effects of 2-substituents and acyl groups on the deacetylation activity is thought to be due to a steric factor. From the energy levels of the frontier orbitals of GAc and its 3- or 4-substituted derivatives, the compound having a lower level of LUMO was shown to be deacetylated effectively. There were marked species differences in the microsomal deacetylation activity toward GAc, and the highest activity was found in the rabbit, followed by the porcine, hamster, rat and then bovine liver microsomes.

Maximal and submaximal forces of slow fibers in human soleus after bed rest

The effects of 2 and 4 mo of bed rest, with or without exercise countermeasures, on the contractile properties of slow fibers in the human soleus muscle were examined. Mean fiber diameters were 8 and 36% smaller after 2 and 4 mo of bed rest, respectively, than the pre-bed rest level. Maximum tetanic force (P(o)), maximum activated force (F(max)) per cross-sectional area (CSA), and the common-logarithm value of free Ca(2+) concentration required for half-maximal activation (pCa(50)) also decreased after 2 and 4 mo of bed rest. In contrast, maximum unloaded shortening velocity (V(o)) was increased after 2 and 4 mo of bed rest. After 1 mo of recovery, fiber diameters, P(o), F(max) per CSA (P > 0.05), and pCa(50) were increased and V(o) decreased toward pre-bed rest levels. Effects of knee extension/flexion exercise by wearing an anti-G Penguin suit for 10 h daily, and the effects of loading or unloading of the plantar flexors with (Penguin-1) or without (Penguin-2) placing the elastic loading elements of the suit, respectively, were investigated during ~2 mo of bed rest. In the Penguin-1 group, mean fiber diameter, P(o), F(max) per CSA, V(o), and pCa(50) were similar before and after bed rest. However, the responses of fiber size and contractile properties to bed rest were not prevented in the Penguin-2 group, although the degree of the changes was less than those induced by bed rest without any countermeasure. These results indicate that long-term bed rest results in reductions of fiber size, force-generation capacity, and Ca(2+) sensitivity, and enhancement of shortening velocity in slow fibers of the soleus. The data indicate that continuous mechanical loading on muscle, such as stretching of muscle, is an effective countermeasure for the prevention of muscular adaptations to gravitational unloading.

Ion selectivities of the Ca(2+) sensors for exocytosis in rat phaeochromocytoma cells

1. The ion selectivities of the Ca(2+) sensors for the two components of exocytosis in rat phaeochromocytoma (PC12) cells were examined by measurement of membrane capacitance and amperometry. The cytosolic concentrations of metal ions were increased by photolysis of caged-Ca(2+) compounds and measured with low-affinity indicators benzothiazole coumarin (BTC) or 5-nitrobenzothiazole coumarin (BTC-5N). 2. The Ca(2+)-induced increases in membrane capacitance comprised two phases with time constants of 30--100 ms and 5 s. Amperometric events reflecting the exocytosis of large dense-core vesicles occurred selectively in the slow phase, even with increases in the cytosolic Ca(2+) concentration of > 0.1 mM. 3. The slow component of exocytosis was activated by all metal ions investigated, including Cd(2+) (median effective concentration, 18 pM), Mn(2+) (500 nM), Co(2+) (900 nM), Ca(2+) (8 microM), Sr(2+) (180 microM), Ba(2+) (280 microM) and Mg(2+) (> 5 mM). In contrast, the fast component of exocytosis was activated by Cd(2+) (26 pM), Mn(2+) (620 nM), Ca(2+) (24 microM) and Sr(2+) (320 microM), but was only slightly increased by Ba(2+) (> 2 mM) and Co(2+) and not at all by Mg(2+). 4. The fast component, but not the slow component, was competitively blocked by Na(+) (median effective concentration, 44 mM) but not by Li(+), K(+) or Cs(+). Thus, the Ca(2+) sensor for the fast component of exocytosis is more selective than is that for the slow component; moreover, this selectivity appears to be based on ionic radius, with cations with radii of 0.84 to 1.13 A (1 A = 0.1 nm) being effective. 5. These data support a role for synaptotagmin--phospholipid as the Ca(2+) sensor for the exocytosis of large dense-core vesicles and they suggest that an additional Ca(2+)-sensing mechanism operates in the synchronous exocytosis of synaptic-like vesicles.

Coronary artery bypass grafting for patients with an atherosclerotic ascending aorta

OBJECTIVES

We review the outcome of coronary artery bypass grafting in patients with a severe atherosclerotic ascending aorta.

METHODS

Subjects were 31 patients averaging 69.4 +/- 6.9 years old studied from 1990 through 1998. Ascending aortic lesions were assessed using epiaortic echo and 2 types of aortic nonclamping techniques applied. In 29 patients operated on in the early years, bypass grafting was conducted on the hypothermic fibrillated heart in 22 and on the beating heart in 7. The remaining 2 underwent off-pump coronary artery bypass grafting more recently. For cases with multivessel disease, we used composite grafting.

RESULTS

Three patients developed mild stroke and 5 died within 30 days of surgery--4 from multiple emboli (1 accompanied by a stroke) and 1 from perioperative myocardial infarction. One hospital death occurred due to brain damage and multiorgan failure following unexpected rupture of a saphenous vein graft. No cardiac deaths occurred in the late stage of our series. Actuarial survival was 73.0% for 3 years and 68.0% for 5 years. Freedom from cardiac events was favorable in the remaining 25 survivors.

CONCLUSIONS

Outcome was suboptimal for the risks involved. Recent technical advances, including coronary surgery on the beating heart with or without cardiopulmonary bypass using variable in-situ or free arterial grafts, associated with adequate evaluation of systemic atherosclerosis, should improve this outcome.

Clinical characteristics of patients with constrictive pericarditis after coronary bypass surgery

Constrictive pericarditis (CP) is an unusual sequela of cardiac surgery, so the present study evaluated the clinical characteristics of patients with CP after coronary artery bypass grafting (CABG). Four hundred and sixty-three patients who underwent isolated CABG between January 1989 and March 1999 were examined retrospectively. The first choice of treatment for postoperative pericardial effusion was non-steroid anti-inflammatory agents, and an increased dose of diuretics. The second treatment choice was corticosteroids or pericardial drainage. When CP was suspected during the follow-up period (mean, 54+/-31 months), cardiac catheterization was carried out to establish the diagnosis. Of the 463 patients undergoing CABG, there were 11 (2.4%) who developed CP after surgery. The median time to the onset of symptoms after CABG was 4 weeks (range, 3-96 weeks). On univariate and multivariate analysis, normal left ventricular ejection fraction, warfarin administration, and early postoperative pericardial effusion were significantly associated with a greater potential of postoperative CP. The effusion was bloody in all cases of pericardial drainage despite warfarin therapy. Not draining the postoperative effusive pericardial effusion was a risk factor for the development of CP. Pericardial drainage for patients with significant effusion after CABG is important for the prevention of subsequent CP, especially in those patients being treated with warfarin or with normal left ventricular function.

Indocyanine green elimination rate detects hepatocellular dysfunction early in septic shock and correlates with survival

OBJECTIVE

To determine whether indocyanine green clearance is an early indicator of hepatocellular injury in septic shock and to assess its predictive value.

DESIGN

Observational study with prospective data collection.

SETTING

Traumatology and critical care unit in a city hospital, staffed by traumatology and intensive care clinicians.

PATIENTS

Twelve patients in septic shock who survived at least 2 months (group S) and nine patients who died within 2 wks (group N).

INTERVENTIONS

Routine resuscitation from septic shock (surgery, fluid loading, and administration of catecholamines and antibiotic drugs).

MEASUREMENTS AND MAIN RESULTS

Pulmonary artery occlusion pressure, cardiac index, oxygen delivery index, oxygen consumption index, and the indocyanine green elimination rate constant (KICG; or the slope of the loge [indocyanine green concentration] vs. time curve) 3-9 mins after injection were measured within 12 hrs of the onset of hypotension, then at 24 hrs, and every 24 hrs thereafter. Alanine aminotransferase and total bilirubin were measured on day 0 and day 1. Volume of fluid administered and duration of shock were the same in survivors and nonsurvivors. The oxygen consumption index was higher in survivors at 12 hrs, but no intergroup difference in pulmonary artery occlusion pressure, cardiac index, or oxygen delivery index was significant at any time point. KICG in nonsurvivors was lower than in survivors both initially and after 24 hrs, and it was subnormal in all patients except one survivor (p <.05). The KICG increased between 24 and 120 hrs in 11 survivors but progressively decreased and remained below 0.05 in seven nonsurvivors. The remaining two nonsurvivors died within 24 hrs of the initial measurement of KICG, which was >0.05. Alanine aminotransferase and total bilirubin were less sensitive measures of hepatic dysfunction in the first 24 hrs than the KICG.

CONCLUSIONS

The KICG can identify reversible liver injury in septic shock, suggesting good prognosis. Either failure to increase the KICG within 120 hrs or an extremely low KICG is a poor prognostic sign.

Strategy for the treatment of inaccessible unruptured giant and large aneurysms of the internal carotid artery

Our goal was to clarify the optimum management of the inaccessible unruptured giant and large aneurysms of the internal carotid artery (ICA). Since 1981, we have treated 18 patients with unclippable unruptured giant or large aneurysms of the ICA. Aneurysms were classified as either intracavernous or intradural. We performed proximal carotid occlusion in 12 patients and conservatively treated six patients. We retrospectively analyzed long-term outcomes in these patients. Four of seven patients with intradural aneurysm underwent proximal carotid occlusion, with good long-term outcomes. The three patients with intradural aneurysm, who were treated conservatively, died of subarachnoid hemorrhage. Eight of 11 patients with intracavernous aneurysm underwent proximal carotid occlusion, one dying of massive nasal bleeding 25 months after the procedure. In this case, the aneurysm was partially thrombosed, and residual lumen growth was revealed 22 months after proximal carotid occlusion. Cranial nerve paresis improved in five of the eight patients (63%), and two patients had a minor ischemic attack. Neurological problems failed to occur in the three patients with intracavernous aneurysm who were treated conservatively. The risk of rupture is relatively high in intradural giant and large aneurysms. Proximal carotid occlusion can effectively prevent bleeding from intradural aneurysms. Aggressive management is justified for intradural aneurysms with poor collateral circulation. Operative procedures in the management of an intracavernous aneurysm require careful consideration.

Identification of the T cell clones expanding within both CD8+CD28+ and CD8+CD28− T cell subsets in recipients of allogeneic hematopoietic cell grafts and its implication in post-transplant skewing of T cell receptor repertoire

We have previously reported that skewed repertoires of T cell receptor-beta chain variable region (TCRBV) and TCR-alpha chain variable region (TCRAV) are observed at an early period after allogeneic hematopoietic cell transplantation. Furthermore, we found that T lymphocytes using TCRBV24S1 were increased in 28% of the recipients of allogeneic grafts and an increase of TCRBV24S1 usage was shown to result from clonal expansions. Interestingly, the arginine residue was frequently present at the 3' terminal of BV24S1 segment and was followed by an acidic amino acid residue within the CDR3 region. These results suggest that these clonally expanded T cells are not randomly selected, but are expanded by stimulation with specific antigens. This study was undertaken to elucidate the mechanisms of the post-transplant skewing of TCR repertoires. Since the CD8(+)CD28(-)CD57(+) T cell subset has been reported to expand in the peripheral blood of patients receiving allogeneic hematopoietic cell grafts, we examined the TCRAV and TCRBV repertoires of the CD8(+)CD28(-) T cell and CD8(+)CD28(+) T cell subsets, and also determined the clonality of both T cell populations. In all three recipients examined, the CD8(+)CD28(-) T cell subset appeared to define the post-transplant TCR repertoire of circulating blood T cells. Moreover, the CDR3 length of TCRBV imposed constraints in both CD8(+)CD28(-) T cell and CD8(+)CD28(+) T cell subsets. The DNA sequences of the CDR3 region were determined, and the same clones were identified within both CD8(+)CD28(-) and CD8(+)CD28(+) T cell subsets in the same individuals. These results suggest that the clonally expanded CD8(+)CD28(-) T cells after allogeneic hematopoietic cell transplantation derive from the CD8(+)CD28(+) T cell subset, possibly by an antigen-driven mechanism, resulting in the skewed TCR repertoire.

Antitumor effect of a new selective matrix metalloproteinase inhibitor, MMI-166, on experimental pancreatic cancer

The antitumor effect of a new matrix metalloproteinase inhibitor, MMI-166, which is a selective inhibitor of MMP-2 and -9, was examined in the hamster pancreatic cancer cell line PGHAM-1. In vitro, MMI-166 inhibited the gelatinase activity of MMP-2 and -9 derived from PGHAM-1 cells, and dose-dependently inhibited invasion of PGHAM-1 through a basement membrane-like barrier. MMI-166 showed no apparent cytotoxicity to PGHAM-1 cells in culture at 100 microgram/ml. MMI-166 (200 mg/kg) or vehicle were administered orally, once daily, from day 1 until day 21 after implantation in the orthotopic implantation model of PGHAM-1. MMI-166 significantly reduced the incidence of liver surface metastasis from 66.7% to 20.0%, and it reduced the number of liver surface metastases per animal from 6.17 to 2.00, but this reduction was not significant. MMI-166 significantly reduced the volume of pancreatic tumors from 718.3 +/- 220.0 mm(3) to 222.8 +/- 85.4 mm(3). Treatment of pancreatic tumors with MMI-166 caused a significant reduction in the microvessel density from 37.90 +/- 10.18/mm(2) to 16.16 +/- 3.15/mm(2) and a significant increase in apoptotic index from 1.75 +/- 0.41% to 3.96 +/- 0.38%, but there was no significant difference between tumor cell proliferation in the MMI-166-group and the control group. These results showed that selective MMP inhibition could limit both cancer spread and angiogenesis in pancreatic cancer. The selective MMP-2 and -9 inhibitor MMI-166 may be of therapeutic use in the treatment of pancreatic cancer because of its inhibitory effect on invasion and angiogenesis.

Oligoclonal expansion of CD4(+)CD28(-) T lymphocytes in recipients of allogeneic hematopoietic cell grafts and identification of the same T cell clones within both CD4(+)CD28(+) and CD4(+)CD28(-) T cell subsets

Recipients of allogeneic bone marrow grafts have clonally expanded CD8(+)CD28(-) T lymphocytes during the early period after transplantation, which leads to skewing of T cell receptor (TCR) repertoires. Here, we have addressed the question of whether clonal expansion of CD28(-) T cells is also observed in CD4(+) T lymphocytes after human allogeneic hematopoietic cell transplantation. We found that the fraction of T cells lacking CD28 expression in the CD4(+) subset was increased after transplantation, and expanded CD4(+)CD28(-) T lymphocytes carrying certain TCRBV subfamilies showed limited TCR diversity. In order to further study the ontogeny of CD4(+)CD28(-) T cells, we analyzed the complementarity-determining region 3 (CDR3) of the TCR-beta chain of CD4(+)CD28(+) and CD4(+)CD28(-) cells. We identified the same T cell clones within both CD4(+)CD28(-) and CD4(+)CD28(+) T cell subsets. These results suggest that both subsets are phenotypic variants of the same T cell lineage.

Retrovesical desmoplastic small round cell tumor in a patient with urinary frequency

A 21-year-old man with urological symptoms was found to have a large abdominal tumor in the retrovesical space between the bladder and the rectosigmoid colon. Radiologic findings revealed little evidence confirming the diagnosis. A transrectal biopsy failed to disclose the histopathologic origin of the tumor. An exploratory laparotomy with a complete surgical resection was impossible, so a wedge biopsy was performed. Combined histologic and immunohistochemical findings revealed the features of desmoplastic small round cell tumor (DSRCT). Despite subsequent multi-agent chemotherapy, the patient died as a result of the growing tumor and liver metastasis. There have been only two prior reports of this neoplasm in the urological literature.

TNFalpha decreases gluconeogenesis in hepatocytes isolated from 10-day-old rats

Gluconeogenesis decreases during septic shock, but its mechanism is not well known. Tumor necrosis factor alpha (TNF-alpha), which is a key cytokine in septic shock, can increase GLUT1 gene expression and glucose uptake in muscles and fatty tissues. TNF-alpha does not alter the metabolism of hepatocytes in which GLUT2 is the predominant glucose transporter. However, GLUT1 is the predominant glucose transporter in hepatocytes of 10-d-old rats. Thus, we hypothesized that TNF-alpha might increase glucose uptake and glycolysis in those cells, and decrease gluconeogenesis. In the present study, hepatocytes isolated from 10-d-old rats were incubated with TNF-alpha at the concentrations of 0, 0.98, 9.8, 98, and 980 ng/mL to evaluate TNF-alpha effects on gluconeogenesis and glucose uptake. TNF-alpha increased glucose uptake (41.1 +/- 8 to 114 +/- 21.4 micromol/10(6) cells at the concentration of 980 ng/mL of TNF-alpha) in a dose-dependent manner, and decreased gluconeogenesis (98.2 +/- 8.2 to 1.1 +/- 3.2 micromol/10(6) cells at the concentration of 980 ng/mL of TNF-alpha) in a dose-dependent manner. The decrease of glucokinase mRNA and GLUT1 mRNA abundance correlated with glucose uptake (r = 0.988 and 0.997, respectively), and the decrease of phosphoenolpyruvate carboxykinase mRNA abundance correlated with the decrease of gluconeogenesis (r = 0.972). The decrease of gluconeogenesis by TNF-alpha correlated with the increase of glucose uptake (r = -0.988). We concluded that TNF-alpha reciprocally suppressed gluconeogenesis in hepatocytes isolated from 10-d-old rats.

[A case of spinal dural AVF treated by endovascular embolization]

Here we report a case of spinal dural arteriovenous fistula(AVF) treated by endovascular embolization. A 58-year-old female presented with progressive intermittent claudication and numbness of the lower extremities. MRI showed swelling of the spinal cord with intramedullary high signal intensity on T2-weighted image and intramedullary enhancement, suggested spinal cord myelopathy. Myelography demonstrated the dilated serpentine vessels in the subarachnoid space and focal filling defect. Angiography showed spinal dural AVF fed by bilateral lateral sacral artery. The draining vein was posterior spinal vein. Endovascular embolization using liquid material was performed under general anesthesia. The injection of glue included the distal feeding artery, the shunt itself and the initial part of draining vein. A complete cure was achieved, with a normal postoperative angiogram. MRI returned to normal with complete disappearance of T2 high signal, cord enlargement and enhancement by contrast medium. It was suggested that venous congestion induced the transient spinal ischemia, manifested as intermittent claudication. Endovascular embolization using liquid material was safe and quite effective for spinal dural AVF.

Anti-metastatic efficacy and safety of MMI-166, a selective matrix metalloproteinase inhibitor

The anti-metastatic efficacy and safety of a newly-developed matrix metalloproteinase (MMP) inhibitor were examined. MMI-166, a N-sulfonylamino acid derivative, inhibited the enzyme activity of MMP-2, 9, and 14 but not MMP-1, 3 or 7. Daily oral administration of MMI-166 resulted in potent inhibition of metastatic lung colonization of Lewis lung carcinoma injected via the tail vein and liver metastasis of C-1H human colon cancer implanted into the spleen at inhibition levels of 43% and 63%, respectively. Daily administration of MMI-166 also resulted in prolonged survival of mice given intraperitoneal implantation of Ma44 human lung cancer cells. The anti-metastatic activity of MMI-166 was as effective as that of other MMP inhibitors with broad inhibitory spectrum. MMI-166 did not affect in vitro tumor cell growth. Neither body weight losses nor hematotoxicity was observed during long-term treatment, indicating the safety of MMI-166 in mice. These results indicate that the selective MMP inhibitor MMI-166 has therapeutic potential as an anti-metastasis agent.

Extensive clonal expansion of T lymphocytes causes contracted diversity of complementarity-determining region 3 and skewed T cell receptor repertoires after allogeneic hematopoietic cell transplantation

We previously described skewed repertoires of the T cell receptor-beta chain variable region (TCRBV) and the TCR-alpha chain variable region (TCRAV) soon after allogeneic hematopoietic cell transplantation. To determine the characteristics of skewed TCRBV after transplantation, we examined the clonality of T lymphocytes carrying skewed TCRBV subfamilies and determined the CDR3 sequences of expanded T cell clones. In all 11 recipients examined, TCR repertoires were skewed, with an increase of certain TCRBV subfamilies that differed among individuals. In nine of 11 patients, clonal/oligoclonal T cell expansion was observed, although the expanded T cells were not necessarily oligoclonal. The extent of expansion after transplantation appeared to predict clonality. The arginine (R)-X-X-glycine (G) sequence was identified in clonally expanded T cells from four of five recipients examined, and glutamic acid (E), aspartic acid (D) and alanine (A) were frequently inserted between R and G. These results suggest that T lymphocyte expansion may result from the response to antigens widely existing in humans, and that the extensive clonal expansion of a limited number of T cells leads to contracted CDR3 diversity and post-transplant skewed TCR repertoires.

Effect of NaClO treatment on bonding to root canal dentin using a new evaluation method

The purposes of this study were to investigate the reliability and efficiency of a new evaluation method for resin bonding to root canal dentin, which measures both marginal adaptation and shear bond strength simultaneously, and to determine the effects of root canal irrigants on resin bonding. A wet bonding system (Single Bond) and a self-etching primer system (Clearfil Mega Bond) were employed; NaClO was used as a root canal irrigant. No gaps or changes in bond strength were observed despite the NaClO treatment when the wet bonding system was employed, while the gap formation ratio increased, and bond strength decreased with longer NaClO treatment time when the self-etching primer system was employed. These findings suggested that this new experimental method was effective for evaluating resin systems to the root canal wall dentin which is affected by irrigation with NaClO.

Molecular cloning and characterization of a cDNA for a novel ethylene receptor, NT-ERS1, of tobacco (Nicotiana tabacum L.)

The cDNA encoding a novel member (NT-ERS1) of ethylene receptor family of tobacco (Nicotiana tabacum L.) was obtained by a combination of RT-PCR and 5'-/3'-RACE cloning. The cDNA was 2,092 nucleotides long and had an open reading frame of 1,911 bp encoding 637 amino acids. The deduced polypeptide lacked a response regulator domain, indicating that the ethylene receptor belongs to an ERS-group. The amino acid sequence was similar to respective members of the tobacco ethylene receptor family: 67.8% to NT-ETR1, 39.1% to NTHK1 and 31.1% to NTHK2. Comparison of amino acid sequence suggested that NT-ERS1 is the counterpart of Nr in the ethylene receptor family of tomato, which belongs to Solanaceae as does tobacco. Northern blot analysis showed that mRNA of NT-ERS1 was present in leaf, shoot and root tissues, and accumulated in leaves treated with exogenous ethylene. A mutated NT-ERS1 cDNA transgene, obtained by introducing one nucleotide substitution into NT-ETR1 cDNA, conferred ethylene insensitivity in tobacco plants, indicating that the translation product of the cDNA actually functioned in the plants.

Regional cerebral glucose metabolism of patients with malignant diseases in different clinical phases

BACKGROUND

Psychological and psychiatric aspects of cancer patients have not been studied well in terms of functional neuroimaging. The aim of this pilot study was to investigate the relationship between regional cerebral metabolism and different clinical phases.

MATERIAL AND METHODS

Relative cerebral glucose metabolism of 77 Japanese patients with various types of malignant diseases was studied by positron emission tomography with 18F-fluorodeoxyglucose. They were subgrouped into the 1) pre-treatment, 2) post-treatment, 3) recurrence and 4) terminal patient groups. These subgroups were compared to the control group of 17 in-patients with benign diseases, using voxel-based Statistic Parametrical Mapping software (SPM).

RESULTS

Relative reduction in the regional cerebral metabolism was detected in the prefrontal and basolateral (inferolateral) prefrontal cortex, orbitofrontal cortex, anterior and posterior cingulate gyrus, insula, basal ganglia, hippocampus and thalamus in the pre-treatment group. The anterior and posterior cingulate gyri were hypometabolic only in the pre-treatment group. Hypometabolic areas were detected only in the basolateral prefrontal cortex, orbitofrontal cortex, ventral part of cingulate gyrus and insula in the post-treatment group. In the terminal group, the hypometabolic pattern seemed very close to that in the pre-treatment group. The results seemed to suggest that hypometabolic findings before treatments could reverse after treatments but became prominent again in terminal stages. These results do not contradict with previous epidemiological findings that high incidence of adjustment disorders was seen in earlier stages and more brain organic syndromes were seen in terminal stages.

CONCLUSION

It could be speculated that decreased metabolism in early stages reflects state-dependent changes and that decreased metabolism in the terminal stages reflects organic brain damages. brain of cancer patients show a fluctuation in the regional metabolism. This finding might give a suggestion that functional imaging could be used as a supplementary method for psychological evaluation of patients with severe diseases.

Screening for primary hyperparathyroidism (PHPT) in clinic patients: differential diagnosis between PHPT and malignancy-associated hypercalcemia by routine blood tests

Screening for primary hyperparathyroidism (PHPT) by measurement of the serum calcium concentration detects one patient per 500-1000 individuals in Western countries, and one patient per 2500-5000 subjects in Japan. Among clinic patients, however, the presence of many false-positive cases due to malignancy-associated hypercalcemia (MAH) reduces the benefit of such screening. We evaluated a new method of screening for PHPT based on the results of routine blood tests using the hospital information system (HIS) at our hospital. This new method could distinguish PHPT from MAH. This study included 25179 blood samples in which the serum calcium (Ca), albumin (Alb), chloride (Cl) and inorganic phosphate (IP) concentrations had been measured between March, 1994 and February, 1995 at Osaka University Medical Hospital. The HIS was programmed to pick blood samples that satisfied Formula 1 [Ca(mEq/ml) > 0.3 x Alb(g/dl) + 4.1] and Formula 2 ([Cl(mEq/ml)-84] x [10 x Alb-15]/[IP(mg/dl)/3.1] > 400). Of data from 25179 blood samples collected, those from 54 patients satisfied both Formulae 1 and 2. The patients from which these samples were derived from were subject to further analysis: medical records were studied and the intact-parathyroid hormone concentration was measured if necessary. Of these 54 cases, 19 patients (35.2%) were subsequently diagnosed with PHPT, including two, who were newly diagnosed with PHPT by this screening procedure. Although 35 (64.8%) of 54 patients were false-positive, many of them were treated with blood purification therapies in the Department of Pediatrics or the Intensive Care Unit (ICU). On the other hand, there were four false-positive cases (7.4%) caused by MAH. False-negative case in this study was only one patient (5%), whose diagnosis was normocalcemic PHPT. When omitting samples from pediatric patients and those in ICU, this screening procedure for PHPT has the advantage of being able to differentiate this diagnosis from MAH.

Three-dimensional characterization of interior structures of exocytotic apertures of nerve cells using atomic force microscopy

We examined the interior structure of exocytotic apertures in synaptic vesicles of neuroblastoma x glioma hybrid cells using atomic force microscopy. The atomic force microscopy detected apertures of 50-100nm in diameter at various depths within the varicosities of these cells. We were also able to image a regular radial pattern on the wall and lump-like structures at the bottom of these apertures. In contrast, scanning electron microscopy could only detect the apertures but not the fine details of their interior. The cells examined here exhibited the same electrophysiological properties and expression of synaptophysin and syntaxin 1 as presynaptic terminals, as studied by various electrophysiological and imaging techniques. Our results indicate that atomic force microscopy allows three-dimensional viewing of the fine structures located inside exocytotic apertures in nerve cells.

Sapecin B alters kinetic properties of rapidly inactivating K(+) channels in rat pituitary GH(3) cells

Sapecin B is an antibacterial protein isolated and purified from culture medium of the embryonic cell line derived from the flesh fly (Sarcophaga peregrina). It has structural similarities to the scorpion toxin charybdotoxin (CTX). We have first detailed the effects of the newly described toxin (sapecin B) on the gating kinetics of the 4-aminopyridine-sensitive, rapidly inactivating K(+) current in rat pituitary GH(3) cells in order to investigate this protein's site of action, with whole-cell voltage-clamp methods. We have found that sapecin B alters the kinetics of activation and deactivation whereas there was no effect on the inactivation process. None of the effects of sapecin B was voltage dependent. In addition, sapecin B reduced whole-cell conductance. We suggest that the toxin may be ineffective against the voltage-sensitive segment, as well as the N-terminal and C-terminal domains, and CTX and sapecin B probably may have different binding sites.

Identification of two novel splicing variants of human type II iodothyronine deiodinase mRNA

Human type II iodothyronine deiodinase (hDII) belongs to a family of selenoproteins. It catalyzes 5'-deiodination of thyroxine to generate an active thyroid hormone, 3,3',5-triiodothyronine. Two novel splice variants of hDII gene transcript; namely hDII-b and hDII-c, were identified. Three distinct DNA fragments (hDII-a-c) were amplified by a reverse transcription-polymerase chain reaction (RT-PCR) with hDII intron-spanning primers using total-RNA from human umbilical vein endothelial cell line, ECV304. The sequence of hDII-a was identical to that of previously reported hDII. hDII-b and hDII-c had an additional insertion of 108 and 242 bp, respectively. The insertion sequences were found in the intron of hDII gene, therefore, two novel exons exist between exons 1 and 2 of hDII gene. The splice sites of new exons (b and c) conserved the consensus sequences of splice acceptor and donor sites. hDII-b contains exon b with an in-frame TGA codon that may encode an extra selenocysteine. hDII-c contained exons b and c and the predicted open reading frame is interrupted by a stop codon (TAA) produced by a frame shift. RT-PCR analysis showed that hDII-a and hDII-b mRNAs are expressed in human tissues including brain, kidney, lung and trachea. The mRNA abundance of hDII-c was lower than that of hDII-a or hDII-b. Thus, the new variants of hDII transcripts suggest the presence of two short exons between exons 1 and 2 of hDII gene, and of functional variant of hDII.

X-ray telescope onboard Astro-E: optical design and fabrication of thin foil mirrors

X-ray telescopes (XRT's) of nested thin foil mirrors are developed for Astro-E, the fifth Japanese x-ray astronomy satellite. Although the launch was not successful, the design concept, fabrication, and alignment procedure are summarized. The main purpose of the Astro-E XRT is to collect hard x rays up to 10 keV with high efficiency and to provide medium spatial resolution in limited weight and volume. Compared with the previous mission, Advanced Satellite for Cosmology and Astrophysics (ASCA), a slightly longer focal length of 4.5-4.75 m and a larger diameter of 40 cm yields an effective area of 1750 cm2 at 8 keV with five telescopes. The image quality is also improved to 2-arc min half-power diameter by introduction of a replication process. Platinum is used instead of gold for the reflectors of one of the five telescopes to enhance the high-energy response. The fabrication and alignment procedure is also summarized. Several methods for improvement are suggested for the reflight Astro-E II mission and for other future missions. Preflight calibration results will be described in a forthcoming second paper, and a detailed study of images will be presented in a third paper.

Evaluation of the efficacy and safety of laparoscopic nephrectomy

PURPOSE

To evaluate the efficacy and safety of laparoscopic nephrectomy.

METHODS

From June 1994 to November 1999, 10 patients underwent laparoscopic nephrectomy at Osaka University Medical Hospital and Osaka Rosai Hospital. Laparoscopic nephrectomy was performed either via transperitoneal or retroperitoneal approach under general anesthesia. These 10 cases were reviewed in respect of primary disease of the kidney, operative time, complications and postoperative convalescence.

RESULTS

Of the 10 patients, five were preoperatively diagnosed as having a non-functioning kidney with hydronephrosis, two patients were diagnosed as having an atrophic kidney, two had renal cell carcinoma and one had renal pelvic tumor. The average operative time was 374 min (range 270-675 min). The mean blood loss was 330 mL (range 60-800 mL). One patient required transfusion due to postoperative oozing. The average hospital stay after operation was 7 days. No major postoperative complications were observed.

CONCLUSION

Laparoscopic nephrectomy is an option in surgically managing renal disorders, including malignancies, although it has a longer operative time compared to conventional open surgery.

Cyclic AMP regulates the calcium transients released from IP(3)-sensitive stores by activation of rat kappa-opioid receptors expressed in CHO cells

We analyzed intracellular Ca(2+)and cAMP levels in Chinese hamster ovary cells expressing a cloned rat kappa opioid receptor (CHO-kappa cells). Although expression of kappa(kappa)-opioid receptors was confirmed with a fluorescent dynorphin analog in almost all CHO-kappa cells, the kappa-specific agonists, U50488H or U69593, induced a Ca(2+) transient only in 35% of the cells. The Ca(2+) response occurred in all-or-none fashion and the half-maximal dosage of U50488H (812.1nM) was higher than that (3.2nM) to inhibit forskolin-stimulated cAMP. The kappa-receptors coupled to G(i/o)proteins since pertussis toxin significantly reduced the U50488H actions on intracellular Ca(2+) and cAMP. The Ca(2+) transient originates from IP(3)-sensitive internal stores since the Ca(2+) response was blocked by a PLC inhibitor (U73122) or by thapsigargin depletion of internal stores while removal of extracellular Ca(2+) had no effect. Interestingly, application of dibutyryl cAMP (+ 56.2%) or 8-bromo-cAMP (+ 174.7%) significantly increased the occurrence of U50488H-induced Ca(2+) mobilization while protein kinase A (PKA) inhibitors, Rp-cAMP (-32.3%) or myr-psi PKA (-73.9%) significantly reduced the response. Therefore, it was concluded that cAMP and PKA activity can regulate the Ca(2+) mobilization. These results suggest that the kappa receptor-linked cAMP cascade regulates the occurrence of kappa-opioid-mediated Ca(2+) mobilization.

Activation of caspase-3 by lysosomal cysteine proteases and its role in 2,2'-azobis-(2-amidinopropane)dihydrochloride (AAPH)-induced apoptosis in HL-60 cells

We previously reported that in addition to mitochondrial cytochrome c dependent activation, lysosomal cysteine proteases were also involved in the activation of caspase-3. In this study, we have separately obtained the lysosomal and mitochondrial caspase-3 activating factors in a crude mitochondrial fraction and characterized their ability to activate pro-caspase-3 in the in vitro assay system. When a rat liver crude mitochondrial fraction containing lysosomes (ML) was treated with a low concentration of digitonin, lysosomal factors were selectively released without the release of a mitochondrial factor (cytochrome c, Cyt.c). Treatment of ML with Ca(2+) in the presence of inorganic phosphate (P(i)), in contrast, released mitochondrial Cyt.c without the release of lysosomal factors. The obtained lysosomal and mitochondrial factors activated caspase-3 in different manners; caspase-3 activation by lysosomal and mitochondrial factors was specifically suppressed by E-64, a cysteine protease inhibitor, and caspase-9 inhibitor, respectively. Thus, the activation of caspase-3 by lysosomal factors was found to be distinct from the activation by mitochondrial Cyt.c dependent formation of the Apaf-1/caspase-9 complex. To further determine whether or not the activation of caspase-3 by lysosomal cysteine proteases is involved in cellular apoptosis, the effect of E-64-d, a cell-permeable inhibitor of cysteine protease, on 2,2'-azobis-(2-amidinopropane)dihydrochloride (AAPH)-induced apoptosis in HL-60 cells was investigated. As a result, DNA fragmentation induced by AAPH was found to be remarkably (up to 50%) reduced by pretreatment with E-64-d, indicating the participation of lysosomal cysteine proteases in AAPH-induced apoptosis in HL-60 cells.

In vitro synergistic interactions between the cisplatin analogue nedaplatin and the DNA topoisomerase I inhibitor irinotecan and the mechanism of this interaction

Among the numerous clinical regimens used in combination chemotherapy, synergy is particularly marked in combinations containing cisplatin (CDDP). However, the clinical use of CDDP is sometimes limited due to its nephrotoxicity. Nedaplatin (NDP) is a second-generation platinum complex with reduced nephrotoxicity that may substitute for CDDP or even surpass it for use in combination with other drugs. We investigated the effects of combinations of NDP and other anticancer drugs on the growth of human small cell lung cancer cells (SBC-3) and non-small cell lung cancer cells (PC-14) using a three-dimensional analysis model. Among the combinations tested, the combination of NDP and irinotecan (CPT-11) showed the most marked synergistic interaction, and the synergism has also been observed against PC-14 cells. With regard to treatment schedule, a remarkable synergistic interaction was produced by concurrent exposure to NDP and CPT-11. On the other hand, sequential exposure to the two drugs led only to additivity. To analyze the interaction between the drugs, the effect of NDP on the 7-ethyl-1-hydroxy-CPT (the active form of CPT-11)-induced inhibitory effect on DNA topoisomerase I was examined. The topoisomerase I-inhibitory effect of 7-ethyl-1-hydroxy-CPT was enhanced 10-fold in the presence of NDP at microgram/milliliter concentrations. These biochemical interactions might be responsible for the synergistic interaction between NDP and CPT-11. These results suggest that the combination of NDP with CPT-11 may be clinically useful for the chemotherapy of lung cancer.

Aortic arch repairs through three different approaches

OBJECTIVES

The outcome of aortic arch repairs by means of three different approaches between 1990 and January 2000 was reviewed.

METHODS

In total 39 patients aged 71.5+/-6.2 years were operated on. The three different surgical approaches depended on the anatomical positions of the aneurysms and on their proximal or distal extension; a median approach was employed in 23 patients, whereas a left postero-lateral approach was used in eight patients. More recently, in eight cases a left antero-lateral approach was applied. All patients underwent open aortic anastomosis without any clamp on or around the aortic arch. During the procedure, the brain was protected by a combination of profound hypothermic circulatory arrest and several techniques of retrograde cerebral perfusion.

RESULTS

Permanent cerebral dysfunction occurred in four patients: two in the median approach and two in the left postero-lateral approach. There were two hospital deaths (5.3%) and six late deaths, all of which belonged either to the median group or to the postero-lateral group. The antero-lateral approach did not produce any cerebral dysfunction, early death, or late death.

CONCLUSIONS

The outcome of aortic arch repairs using profound hypothermic circulatory arrest and variable techniques of retrograde cerebral perfusion, by means of three different approaches, was satisfactory. Of the three approaches, the antero-lateral approach can be employed easily, whether aneurysms extend proximally or distally.

Hemodialysis paradox: survey on the incidence rate of hepatocellular carcinoma in antihepatitis virus C-antibody-positive chronic hemodialysis patients

The prevalence of antihepatitis virus C (HCV) antibodies in chronic hemodialysis (HD) patients is higher than in normal populations, and yet hepatocellular carcinoma (HCC) is infrequent in chronic HD patients who are HCV antibody positive. In this study, we investigated the characteristics of HCV-antibody-positive patients with HCC on chronic HD. A total of 6,366 cases of HCV-antibody-positive patients on chronic HD therapy was analyzed on the basis of answers to questionnaires on the incidence rate of HCC in 314 Japanese dialysis institutions. HCC was a complication in 114 of 6,222 (1.8%) HCV-antibody-positive patients, and cirrhosis was a complication in 536 of 6,242 (8.6%). The incidence rate of both complications was significantly higher in males than in females, and the incidence rate in the chronic HD patients was much lower than in normal populations. Specific immunological status in patients on chronic HD therapy may be an important key for preventing the progression of chronic HCV hepatitis. However, further research is needed because this study was preliminary and excluded the type of HCV virus, pathological findings, and laboratory data.

Synthesis and Biological Evaluation of Cytogenin Derivatives

To enhance the stability in vivo, new derivatives of cytogenin were synthesized, and their biological activity and stability in mice were estimated. 2-(8-Hydroxy-6-methoxy-1-oxo-1H-2-benzopyran-3-yl)propionic acid (NM-3) was found to be the most stable among them. It modified collagen-induced arthritis in mice. It also showed potent anti-angiogenic activity in a mouse dorsal air sac assay.

Preclinical in vivo antitumor efficacy of nedaplatin with gemcitabine against human lung cancer

The antitumor efficacy of the combination of nedaplatin (NDP) with gemcitabine (GEM) was evaluated. We also compared the antitumor activity of NDP plus GEM with that of cisplatin (CDDP) plus GEM or carboplatin (CBDCA) plus GEM. Ma44, which is a human lung cancer sensitive to GEM, and NCI-H460, which is a human lung cancer refractory to GEM, were used in this study. GEM was injected i.v. once followed by i.v. injection of NDP at an interval of approximately 30 min into tumor-bearing athymic mice. GEM was administered again 3 or 4 days thereafter. Combined dosing of NDP with GEM resulted in synergistically enhanced inhibition of tumor growth in the Ma44 tumor model. NDP plus GEM was also effective against Ma44 cells when given late in the therapy, a model for advanced disease. Potent augmentation of growth inhibition by NDP with GEM was also found with the NCI-H460 tumor model. The combination effect of NDP plus GEM appeared to be superior to that of CDDP plus GEM or CBDCA plus GEM in both tumor models. Toxicity in terms of blood cell numbers was not enhanced by the combination of NDP with GEM. These results suggest the effectiveness of combination of NDP with GEM for clinical therapy.

A novel function of synapsin II in neurotransmitter release

Although synapsin has been localized to presynaptic structures, its function remains poorly understood. In the present study, we investigated the presynaptic function of synapsin II using a synaptic vesicle recycling process using synapsin-II-overexpressing NG108-15 cells. Western blot analysis with antibodies for synaptic-vesicle-associated protein indicated that the number of synaptic vesicles was approximately doubled in synapsin II transfectants as reported previously. In differentiated synapsin-II-overexpressing and control cells, the application of high potassium induced strong intracellular calcium elevation along neurites and varicosities after differentiation and a weak calcium rise in the cell bodies. The uptake and release of the fluorescent dye FM1-43 revealed that synaptic vesicle recycling in synapsin-II-transfected cells occurred with the same kinetics in the cell body and neuritic varicosities. Furthermore, the area labeled with FM1-43 fluorescence in the synapsin-II-transfected cells was approximately twice as much as in control cells after stimulation, and ATP released after synaptic vesicle fusion with the plasma membrane in synapsin-II-expressing cells was significantly elevated relative to controls. The number of synaptic vesicles paralleled the amount of transmitter released from the cells leading to the conclusion that the number of releasable synaptic vesicles were increased by synapsin II transfection into NG108-15 cells, suggesting that synapsin II may have a role in the regulation of synaptic vesicle number in presynapse-like structures in NG108-15 cells.

Molecular and functional characterization of HSC54, a novel variant of human heat-shock cognate protein 70

A novel variant of human heat-shock cognate protein 70 (HSC70) transcript, named heat-shock cognate protein 54 (HSC54), was identified and characterized. The transcript encodes the protein lacking 153 amino acid residues of HSC70 in a part of the protein-binding and variable domains, resulting in a calculated molecular mass of 53.5 kDa. HSC54 mRNA was detected in all human cells and tissues examined. The protein was also detected in peripheral mononuclear cells and U937 human histiocytic lymphoma cells. Heat treatment of U937 cells up-regulated the expression of HSC54. The chaperoning activity of HSC54 was examined by luciferase renaturation assay. HSC70 recovered the luciferase activity in the presence of reticulocyte lysate as a source of cochaperones. However, HSC54 did not facilitate the recovery of denatured luciferase; besides, HSC54 significantly inhibited the HSC70-mediated chaperoning activity. In pull-down experiments, HSC54 interacted with cochaperones, p60, HSP40, and p48, as HSC70 did. The resonant mirror detection analysis showed that p60 binds to HSC54 with a higher association rate constant than HSC70 with a similar affinity constant. These results suggest that HSC54 is constitutively expressed and also inducible by stress and may function as an endogenous inhibitory regulator of HSC70 by competing the cochaperones.

Coronary surgery through partial sternotomy in a patient with tracheostoma

We report successful coronary artery bypass grafting through a lower partial sternotomy for a patient with a tracheostoma. He required a tracheotomy for serious laryngeal edema which developed during anesthetic induction prior to elective conventional coronary surgery. A safe alternative approach, comprising a lower midline skin incision with a lower partial sternotomy distant from the stoma, facilitated coronary artery bypass grafting to the left and right coronary arteries after four weeks.