Prophylactic Radiation Therapy Versus Standard of Care for Patients With High-Risk Asymptomatic Bone Metastases: A Multicenter, Randomized Phase II Clinical Trial.

PURPOSE: External-beam radiation therapy (RT) is standard of care (SOC) for pain relief of symptomatic bone metastases. We aimed to evaluate the efficacy of radiation to asymptomatic bone metastases in preventing skeletal-related events (SRE). METHODS: In a multicenter randomized controlled trial, adult patients with widely metastatic solid tumor malignancies were stratified by histology and planned SOC (systemic therapy or observation) and randomly assigned in a 1:1 ratio to receive RT to asymptomatic high-risk bone metastases or SOC alone. The primary outcome of the trial was SRE. Secondary outcomes included hospitalizations for SRE and overall survival (OS). RESULTS: A total of 78 patients with 122 high-risk bone metastases were enrolled between May 8, 2018, and August 9, 2021, at three institutions across an affiliated cancer network in the United States. Seventy-three patients were evaluable for the primary end point. The most common primary cancer types were lung (27%), breast (24%), and prostate (22%). At 1 year, SRE occurred in one of 62 bone metastases (1.6%) in the RT arm and 14 of 49 bone metastases (29%) in the SOC arm (P < .001). There were significantly fewer patients hospitalized for SRE in the RT arm compared with the SOC arm (0 v 4, P = .045). At a median follow-up of 2.5 years, OS was significantly longer in the RT arm (hazard ratio [HR], 0.49; 95% CI, 0.27 to 0.89; P = .018), which persisted on multivariable Cox regression analysis (HR, 0.46; 95% CI, 0.23 to 0.85; P = .01). CONCLUSION: Radiation delivered prophylactically to asymptomatic, high-risk bone metastases reduced SRE and hospitalizations. We also observed an improvement in OS with prophylactic radiation, although a confirmatory phase III trial is warranted.

Treprostinil, a prostacyclin analog, ameliorates ischemia-reperfusion injury in rat orthotopic liver transplantation.

Prostaglandins have been evaluated for their ability to reduce IRI after liver transplantation; however, poor stability, side effects and the inability to show a significant difference in primary endpoint have limited their clinical application. Treprostinil, a prostacyclin (PGI(2) ) analog, has a higher potency and longer elimination half-life than other commercially available PGI(2) analogs. We examined the efficacy of treprostinil to prevent IRI during OLT. OLT was performed in syngeneic Lewis rats after 18 h of cold preservation (4°C) in the UW solution. IRI significantly increased serum ALT and AST levels, neutrophil infiltration, hepatic necrosis and mRNA levels of proinflammatory cytokines post-OLT, while treatment with treprostinil decreased all the parameters. Cold storage of liver grafts significantly reduced ATP levels and treprostinil restored energy levels in liver grafts early postreperfusion. In addition, treprostinil preserved the sinusoidal endothelial cell lining and reduced platelet deposition early post-transplantation compared to placebo. Hepatic tissue blood flow was significantly compromised in the placebo group, whereas treprostinil maintained blood-flow similar to normal levels. Treprostinil protected the liver graft against IRI during OLT. Treprostinil has the potential to serve as a therapeutic option to protect the liver graft against I/R injury in patients undergoing OLT.

Ex vivo application of carbon monoxide in UW solution prevents transplant-induced renal ischemia/reperfusion injury in pigs.

I/R injury is a major deleterious factor of successful kidney transplantation (KTx). Carbon monoxide (CO) is an endogenous gaseous regulatory molecule, and exogenously delivered CO in low concentrations provides potent cytoprotection. This study evaluated efficacies of CO exposure to excised kidney grafts to inhibit I/R injury in the pig KTx model. Porcine kidneys were stored for 48 h in control UW or UW supplemented with CO (CO-UW) and autotransplanted in a 14-day follow-up study. In the control UW group, animal survival was 80% (4/5) with peak serum creatinine levels of 12.0 +/- 5.1 mg/dL. CO-UW showed potent protection, and peak creatinine levels were reduced to 6.9 +/- 1.4 mg/dL with 100% (5/5) survival without any noticeable adverse event or abnormal COHb value. Control grafts at 14 days showed significant tubular damages, focal fibrotic changes and numerous infiltrates. The CO-UW group showed significantly less severe histopathological changes with less TGF-beta and p-Smad3 expression. Grafts in CO-UW also showed significantly lower early mRNA levels for proinflammatory cytokines and less lipid peroxidation. CO in UW provides significant protection against renal I/R injury in the porcine KTx model. Ex vivo exposure of kidney grafts to CO during cold storage may therefore be a safe strategy to reduce I/R injury.

Spinal cord hemangioblastomas in von Hippel-Lindau disease.

STUDY DESIGN: Retrospective data analysis. OBJECTIVE: To clarify the clinical features and surgical management of spinal cord hemangioblastomas in patients with von Hippel-Lindau disease (VHL). SETTING: Clinical VHL Research Group in Japan, Japan. METHODS: Forty-eight out of 66 patients with associated spinal cord hemangioblastoma among 142 VHL patients were retrospectively examined with respect to clinical features, accompanying lesions and outcome of surgical treatment. RESULTS: Among these 48 patients, 46 of them (95.8%) also had a central nervous system (CNS) hemangioblastoma at another site: 42 (87.5%) with cerebellar hemangioblastoma and 11 (22.9%) with brain stem hemangioblastoma. Twenty-three patients (47.9%) had more than one spinal cord hemangioblastoma. The 48 patients with spinal cord hemangioblastomas collectively had a total of 74 tumors. The tumor was accompanied with a syrinx in 64 and without it in 10 patients. Forty of the 48 patients underwent surgical treatment for their spinal cord hemangioblastomas, and 7 of these 40 underwent surgical treatment twice. When functional changes in the patients after these 47 operations were examined by postoperative evaluation by McCormick's classification, 39 of these operations (83.0%) resulted in improvement/no change and 8 (17.0%) in aggravation of symptoms. CONCLUSION: Von Hippel-Lindau disease patients bearing spinal cord hemangioblastomas mostly had a CNS hemangioblastoma at another site. These tumors can be removed in the majority of VHL patients without aggravation. In these patients, when the timing of treatment for spinal cord hemangioblastoma is determined, the probability of occurrence and treatment of other lesions should be considered.

Problems in the current diagnostic standards of clinical N1 non-small cell lung cancer.

BACKGROUND: Although clinical N1 (cN1) non-small cell lung cancer (NSCLC) is considered to be locoregional, the postoperative outcome is disappointing, with a 5 year survival of less than 50%. One possible reason may be that cN1disease diagnosed by current standard imaging modalities often contains unexpected N2 disease. This study was conducted to evaluate the surgical and pathological results of patients with cN1 NSCLC. METHODS: Among 1782 patients with NSCLC who underwent intended curative resection from 1993 to 2003, 143 patients were identified as having cN1 disease and were enrolled in this study. The clinicopathological records and CT films of each patient were retrospectively reviewed to identify predictors for pN2-3 disease. RESULTS: The pathological nodal status was pN0 in 23% (n = 33), pN1 in 47% (n = 67) and pN2-3 in 30% (n = 43) of patients. Patients with pN2-3 showed a significantly worse 5 year survival rate of 38% compared with patients with pN0 (68%) and pN1 (60%) (p = 0.017 and 0.007, respectively). Multivariate analysis showed that adenocarcinoma histology was a significant predictor for pN2-3 disease (OR 3.312, 95% CI 1.439 to 7.784; p = 0.005). The presence of N1 node separate from the main tumour on CT scans tended to predict pN2-3 disease although this did not reach statistical significance (OR 2.103, 95% CI 0.955 to 4.693; p = 0.066). Pathological N2-3 disease was found in 53% of patients with adenocarcinoma with a separate N1 pattern and in only 12% of patients with non-adenocarcinoma with a continuous N1 pattern. CONCLUSIONS: The diagnosis of N1 status by contrast enhanced CT scans is unsatisfactory with a high rate of unexpected pN2 disease. To avoid infertile lung resection, patients with CT diagnosed N1 adenocarcinoma, especially with a separate N1 pattern on CT, should be considered for additional invasive node biopsy modalities, including mediastinoscopy.

A robust control system for targeting melanoma by a supermolecular DDMC/paclitaxel complex.

A DEAE-dextran-MMA copolymer (DDMC)-paclitaxel (PTX) conjugate was prepared using PTX as the guest and DDMC as the host. The resistance of B16F10 melanoma cells to PTX was confirmed, while the DDMC-PTX conjugate showed excellent anticancer activity that followed the Hill equation. The robustness in the tumor microenvironment of the allosteric system was confirmed via BIBO stability. This feedback control system, explained via a transfer function, was very stable and showed the sustainability of the system via a loop, and it showed superior anti-cancer activity without drug resistance from cancer cells. The block diagram of this signal system in the tumor microenvironment used its loop transfer function G(s) and the dN(s) of the external force. This indicial response is an ideal one without a time lag for the outlet response. The cell death rate of DDMC-PTX is more dependent on the Hill coefficient n than on the Michaelis constant Km. This means that this supermolecular reaction with tubulin follows an "induced fit model".

Phosphorylation of neuronal nitric oxide synthase at Ser847 in the nucleus intermediolateralis after spinal cord injury in mice.

We previously demonstrated that Ca2+/calmodulin (CaM)-dependent protein kinase IIalpha (CaM-KIIalpha) can phosphorylate neuronal nitric oxide synthase (nNOS) at Ser847 and attenuate NOS activity in neuronal cells. In the present study we focused on chronological alteration in levels and cellular location of nNOS, phosphorylated (p)-Ser847-nNOS (NP847), CaM-KII and p-Thr286-CaM-KIIalpha following spinal cord injury (SCI) in mice. Western blot analysis showed nNOS to be significantly phosphorylated at Ser847 from 3 h after SCI, peaking at 24 h and gradually decreasing thereafter, and CaM-KII to be colocalized with nNOS after SCI. Immunohistochemical analysis revealed that SCI causes an increase in both NP847 and p-Thr286-CaM-KIIalpha in the nucleus intermediolateralis. These findings suggest that SCI induces p-Thr286-CaM-KIIalpha, which phosphorylates the nNOS at Ser847 in the nucleus intermediolateralis where NO is thought to play a role as a neurotransmitter in autonomic preganglionic neurons. Thus, the NP847 signaling pathway might be involved in the autonomic failure which occurs immediately after SCI.

In vitro transformation of fetal brain cells from CDF rats exposed in utero to N-ethyl-N-nitrosourea: morphologic and immunologic studies.

Inbred CDF rats received 250 mg N-ethyl-N-nitrosourea (ENU)/kg body weight in monosodium phosphate buffer (pH 5.5) during late pregnancy (18-21 days). Control rats received only buffer. One hour after ENU or buffer administration, the fetuses were delivered and fetal brain cells (FBC) were put in long-term tissue culture. Cell growth consisted of monolayers of glial, fibroblastic, and epithelial-like cells. FBC from buffer-treated rats could not be subcultured for more than 13-15 passages; only one culture was maintained up to the 26th passage. FBC from ENU-treated rats showed in vitro malignant transformation beginning at the 8th passage (100 days). Injection of these cells sc into irradiated or neonatally thymectomized syngeneic rats induced small palpable tumors that regressed completely by 15-28 days. Small nonprogressively growing subcutaneous tumors in normal rats, however, were obtained only after the 19th in vitro passage (200 days). These transformed FBC appeared highly antigenic. Tumor-associated antibody was demonmmune adherence assays. Rats immunized with irradiated malignant FBC showed rising tumor antibody titers. The antibody was absorbed by ENU-exposed FBC but not by normal fetal or adult syngeneic brain cells. We concluded that ENU-exposed cells become malignant when grown in vitro for at least 8 passages (100 days) but grow in vivo in X-irradiated or neonatally thymectomized rats only. These antigenic and tumorigenic clones may be selected in vitro, where they grow readily in the absence of immune resistance.

Growth-inhibitory effect of a streptococcal antitumor glycoprotein on human epidermoid carcinoma A431 cells: involvement of dephosphorylation of epidermal growth factor receptor.

An antitumor glycoprotein [streptococcal acidic glycoprotein (SAGP)] purified from an extract of Streptococcus pyogenes inhibited the growth of human epidermoid carcinoma A431 cells overexpressing epidermal growth factor receptor (EGFR) in a time- and a concentration-dependent manner. The antiproliferative effect of SAGP was diminished by preincubating the cells with pertussis toxin and by coadministration of sodium orthovanadate, an inhibitor of protein tyrosine phosphatases (PTPases). Western blot analysis showed that the immunoreactivity of a M(r) 170,000 band of cell lysate to antiphosphotyrosine antibody was reduced by SAGP, and the effect was abolished by sodium orthovanadate. The phosphotyrosine level of the precipitant with anti-EGFR antibody was reduced by SAGP, which was abolished by preincubation with pertussis toxin or by a coadministration with sodium orthovanadate. The PTPase activity transiently increased in the lysate of cells incubated with SAGP and was inhibitable by sodium orthovanadate. Additionally, preincubation of serum-starved A431 cells with SAGP decreased the epidermal growth factor-induced tyrosine phosphorylation of EGFR, and the effect of SAGP was sodium orthovanadate sensitive. These findings indicate that dephosphorylation of the M(r) 170,000 EGFR by activation of PTPase(s) may be responsible in part for the antiproliferative effect of SAGP on A431 cells.

Inhibition of nuclear factor-kappaB activation confers sensitivity to tumor necrosis factor-alpha by impairment of cell cycle progression in human glioma cells.

Tumor necrosis factor (TNF)-alpha has been shown to exert cytotoxic or cytostatic effects on tumor cells, but susceptibility to TNF-alpha varies among different types of cells. TNF-alpha activates a transcription factor, nuclear factor-kappaB (NF-kappaB), which induces a wide variety of genes and causes pleiotrophic responses. In this study, the relationship between susceptibility to TNF-alpha and activation of NF-kappaB was investigated in six human malignant glioma cell lines. Cell proliferation analysis revealed that only one cell line, SK-MG-1, was sensitive to TNF-alpha and that the other five, including U-251MG, were resistant. Electrophoretic mobility-shift assay showed that TNF-alpha strongly activated a subtype of NF-kappaB, the p50-p65 heterodimer, in all of the resistant cell lines tested. However, this activation was weak in the sensitive cell line, SK-MG-1. Activation of NF-kappaB by TNF-alpha in the resistant cell lines resulted in a significant increase of a reporter gene expression driven by NF-kappaB site, suggesting a possibility that activation of p50-p65 confers resistance to TNF-alpha. To test this hypothesis, we established a stable cell line that expresses an inducible dominant negative NF-kappaB (p65 DN) protein in one of the TNF-alpha-resistant cell lines, U-251MG. In the established clone, induction of p65 DN protein decreased TNF-alpha-dependent increase in the DNA binding of p50-p65 heterodimer and NF-kappaB-dependent reporter gene activity. Although no growth inhibition of this clone was observed by TNF-alpha treatment, induction of p65 DN together with TNF-alpha resulted in a significant decrease in cell number. Cell cycle analysis revealed that this growth inhibition was due to the impairment of cell cycle progression. These results indicate that an active NF-kappaB complex, such as the p50-p65 heterodimer, plays a crucial role in the progression of cell cycle in malignant glioma cells. Refractoriness to TNF-alpha treatment could be prevented by inhibiting NF-kappaB activation.

Growth inhibition of glioma cells transfected with the human beta-interferon gene by liposomes coupled with a monoclonal antibody.

A human beta-interferon (HuIFN-beta) gene inserted into a eukaryotic expression vector (pSV2IFN-beta) was entrapped in liposomes having positive charges on their surface. Liposome-mediated transfection of the gene into cultured glioma cells (U251-MG) resulted in the secretion of HuIFN-beta into the medium. The HuIFN-beta level in the culture medium of glioma cells reached 24 +/- 8 (mean +/- SD) IU/ml after 96 h of incubation, at which level the growth inhibitory effect on the cells was found to be greater than 40 times as compared with exogenously added HuIFN-beta. When the plasmid-containing liposomes were coupled with a monoclonal antibody (G-22 MCA) against glioma-associated antigen, the level of HuIFN-beta in the medium was 178 +/- 26 IU/ml, resulting in a 7-fold increase, and the growth inhibitory effect was further elevated. Since the addition of a monoclonal antibody against HuIFN-beta to the medium did not cause the cell growth to resume, the growth inhibitory effect on the cells seems to be ascribed to HuIFN-beta produced in the cells transfected with its gene. Accordingly, the specific delivery of the HuIFN-beta gene into glioma cells by the use of such liposomes might become a useful technique for gene therapy of malignant glioma.

Translocation of exogenous platelet-activating factor and its lyso-compound through plasma membranes is a rate-limiting step for their metabolic conversions into alkylacylglycerophosphocholines in rabbit platelets and guinea-pig leukocytes.

Platelets and leukocytes are known to degrade platelet-activating factor (PAF), a potential mediator of inflammation, to its lyso-derivative (lyso-PAF) and then convert this to 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholines. However, little is known about the mechanism of internalization of PAF and lyso-PAF, which is a prerequisite for their metabolism within the cells. In this work, the internalization of PAF and lyso-PAF by rabbit platelet and guinea-pig leukocyte plasma-membranes were examined by the washing method with bovine serum albumin. The rates of translocation of PAF and lyso-PAF across guinea-pig plasma membranes were significantly higher than those across rabbit platelets. In these cells, the translocation of PAF was found to be accelerated indirectly by activation of PAF receptors by a small portion of added PAF. Results suggest that a temperature-dependent diffusion process is involved in the internalization of these phospholipids. In both rabbit platelets and guinea-pig leukocytes, the translocation of PAF and lyso-PAF through the plasma membranes was shown to be rate-limiting for the metabolic conversion of these compounds to 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholine.

Expression of cytoplasmic galectin-3 as a prognostic marker in tongue carcinoma.

Galectin-3 is a member of the beta-galactoside-binding mammalian lectin family with affinity to ABH group epitopes, cell surface and extracellular polylactosamine glycans. It has been shown to be involved in differentiation, morphogenesis, tumor progression, and metastasis. Here we questioned the possible involvement of galectin-3 in the neoplastic progression of the tongue epithelium and evaluated its prognostic value in tongue cancer patients. Galectin-3 expression was analyzed by the immunohistochemical method in 77 tongue specimens (54 squamous cell carcinomas and 23 specimens of distinct normal mucosa). Levels of nuclear expression of galectin-3 markedly decreased during the progression from normal to cancerous states (P < 0.0001), while cytoplasmic expression increased (P < 0.0001). Enhanced expression of galectin-3 in the cytoplasm was associated with a reduced disease-free survival of tongue cancer patients. Multivariate analysis identified enhanced expression of cytoplasmic galectin-3 as an independent predictor of disease recurrence (P = 0.0120). These results suggest that the observed translocation of galectin-3 from the nucleus to the cytoplasm during neoplastic progression may serve as a prognostic factor for tongue cancer patients.

Balance of risk of therapeutic hypothermia.

The complications of therapeutic hypothermia sometimes undermine its clinical effects. In this study we investigated the efficacy and safety of therapeutic hypothermia based on analysis of 20 severe head injury cases from 6 institutions treated with therapeutic hypothermia in 1999. The twenty patients with severe head injury were enrolled prospectively based on the following indications; Glasgow Coma Scale of 7 or less on admission, age 60 or younger, and systric BP over 100 mmHg. A control group consisting of 21 patients with severe head injury met the same criteria but were treated without therapeutic hypothermia in other institutions. Clinical benefit were evaluated by a comparison of clinical result in the two groups defined according to the Glasgow Outcome Scale six months after injury. The hypothermia group was divided into two groups based on a target temperature [mild hypothermia group: 32-34 degrees C (n = 10); very mild hypothermia group: 35-36 degrees C (n = 10)]. The complication rate, clinical results and the duration of therapeutic hypothermia were analyzed between two groups. In the hypothermia group, 12 patients obtained a favorable outcome (Good Recovery or Moderate Disabled in GOS) and the mortality rate was 35%. In the control group, however only 5 patients had a favorable outcome and the mortality rate was 57%. Comparison between mild hypothermia and very mild hypothermia groups revealed no difference in clinical outcome. In the hypothermia group, severe pneumonia was seen in three patients, all in the mild hypothermia group with a hypothermic duration of over 120 hours. Mild hypothermia should be ended within 120 hours to avoid severe complication. When long-lasting therapeutic hypothermia of more than 120 hours is planned, very mild hypothermia is the treatment of choice.

Biphasic modulation by mGlu5 receptors of TRPV1-mediated intracellular calcium elevation in sensory neurons contributes to heat sensitivity.

BACKGROUND AND PURPOSE: Elevation of glutamate, an excitatory amino acid, during inflammation and injury plays a crucial role in the reception and transmission of sensory information via ionotropic and metabotropic receptors. This study aimed to investigate the mechanisms underlying the biphasic effects of metabotropic glutamate mGlu5 receptor activation on responses to noxious heat. EXPERIMENTAL APPROACH: We assessed the effects of intraplantar quisqualate, a non-selective glutamate receptor agonist, on heat and mechanical pain behaviours in mice. In addition, the effects of quisqualate on the intracellular calcium response and on membrane currents mediated by TRPV1 channels, were examined in cultured dorsal root ganglion neurons from mice. KEY RESULTS: Activation of mGlu5 receptors in hind paw transiently increased, then decreased, the response to noxious heat. In sensory neurons, activation of mGlu5 receptors potentiated TRPV1-mediated intracellular calcium elevation, while terminating activation of mGlu5 receptors depressed it. TRPV1-induced currents were potentiated by activation of mGlu5 receptors under voltage clamp conditions and these disappeared after washout. However, voltage-gated calcium currents were inhibited by the mGlu5 receptor agonist, even after washout. CONCLUSIONS AND IMPLICATIONS: These results suggest that, in sensory neurons, mGlu5 receptors biphasically modulate TRPV1-mediated intracellular calcium response via transient potentiation of TRPV1 channel-induced currents and persistent inhibition of voltage-gated calcium currents, contributing to heat hyper- and hypoalgesia.

Intravenous infusion of adrenomedullin and increase in regional cerebral blood flow and prevention of ischemic brain injury after middle cerebral artery occlusion in rats.

The intravenous infusion of rat adrenomedullin, at concentrations ranging from 0.1 to 1.0 microgram/kg/min, for 60 min increased the regional cerebral blood flow (rCBF) in a dose-dependent manner in rats. rCBF was measured using a laser Doppler flowmetry device placed on the surface of the parietal cortex. The increase in rCBF induced by 1.0 microgram/kg/min of adrenomedullin was up to 145 +/- 10.8% of controls at 60 min (n = 5, p < 0.001). These concentrations of adrenomedullin did not affect systemic blood pressure or other physiologic parameters, including pH, PaCO2, PaO2, hemoglobin, and blood glucose. Repeated infusion of 1.0 microgram/kg/min of adrenomedullin at 2-h intervals caused tachyphylaxis (n = 5, p < 0.01). Rat adrenomedullin (1.0 microgram/kg/min) demonstrated a more potent effect than the same dose of human adrenomedullin. The C-terminal fragment of human adrenomedullin (0.5 and 5.0 micrograms/kg/min), adrenomedullin22-52, which did not affect rCBF alone, inhibited the effect of rat adrenomedullin (0.5 microgram/kg/min) as a receptor antagonist in a dose-dependent manner. In a model of middle cerebral artery (MCA) occlusion in spontaneously hypertensive rats, pre- and postinfusion of 1.0 microgram/kg/min of adrenomedullin suppressed the reduction in rCBF following MCA occlusion (control, 29 +/- 15.1%; adrenomedullin group, 45 +/- 14.4%; not significant) and decreased the volume of ischemic brain injury (control, 288 +/- 35 mm3; adrenomedullin group, 232 +/- 35 mm3; p < 0.05). These results suggest that adrenomedullin increases rCBF and prevents ischemic brain injury, partly by increasing the collateral circulation.

Vasodilator effects on canine basilar artery induced by intracisternal interleukin-1 beta.

The effect of interleukin-1 beta (IL-1 beta) on a cerebral artery was investigated in anesthetized dogs. Intracisternal administration of IL-1 beta (0.03 and 0.3 micrograms) dilated the canine basilar artery in a dose-dependent manner, without affecting systemic blood pressure or heart rate. The increase in diameter induced by 0.3 micrograms of IL-1 beta was 28.4% +/- 13.4% of control at 2 hours and was inhibited by 30 micrograms of the IL-1 beta receptor antagonist, zinc protoporphyrin (4.5% +/- 13.5%, P < 0.05). Interleukin-1 beta did not affect the concentration of nitric oxide metabolites in CSF. However, there was an increase in the concentration of eicosanoids in CSF, and the elevation of 6-keto-PGF1 alpha paralleled the vasodilation. Pretreatment with 30 micrograms of the selective inducible cyclooxygenase (COX-2) inhibitor NS-398 also inhibited the IL-1 beta-induced vasodilation significantly (5.9% +/- 9.4% at 2 hours, P < 0.01). Western blot analysis revealed the expression of a 68-kD COX-2-like protein in basilar artery extracts. These findings suggest that the IL-1 beta-induced vasodilator effect is linked to the prostaglandin cascade, predominantly to prostaglandin I2, by induction of COX-2, but not to the stimulation of nitric oxide metabolism.

Neural activation of the brain with hemodynamic insufficiency.

Little is known about how ischemia affects hemodynamic responses to neural activation in the brain. We compare the effects of a motor activation task and a cerebral vasodilating agent, acetazolamide (ACZ), on regional cerebral blood flow (rCBF) in primary sensorimotor cortex (PSM) in six patients with major cerebral artery steno-occlusive lesions without paresis of the upper extremities. Quantitative rCBF was measured in all patients using H2(15)O autoradiographic method and positron emission tomography. The CBF was determined at rest, during a bimanual motor activation task, and 10 minutes after ACZ administration. With bimanual motor activation, rCBF increased significantly in both PSM compared with at rest (P < 0.01 on lesion side, and P < 0.02 on contralateral side). However, rCBF did not increase after ACZ injection in the PSM on the lesion side, whereas rCBF increased significantly in the contralateral PSM after ACZ injection compared with the level at rest. This result suggests that despite a decreased hemodynamic reserve, there is a nearly normal flow response to neural activation, indicating that the mechanism of vasodilation responsible for perfusion change is different for acetazolamide and neural activation. The relations among neural activation, hemodynamic status, and cerebral metabolism in the ischemic stroke patients are discussed.

Synergism between mild hyperthermia and interferon-beta gene expression.

In the present study, the synergistic effect of mild hyperthermia in combination with gene expression of interferon-beta (IFN-beta) was examined in vitro in the human glioma cell line U87MG. The cells transiently expressed the IFN-beta gene under the control of the mouse mammary tumor virus promoter and were then subjected to temperature elevation (41 degrees C for 1 h). In terms of the cell killing effect, the optimum scheme was obtained by transfection for 4 days before hyperthermia, i.e. rate in the time course of IFN-beta gene expression. The relative specific growth rate decreased to 32% compared with the control while it was only 40% under the hyperthermic conditions. These observations suggest that IFNbeta expression was able to enhance the sensitivity of transfected glioma cells to mild hyperthermia.

Increased expression of cyclooxygenase-2 protein in rat lung tumors induced by N-nitrosobis(2-hydroxypropyl)amine.

Expression of cyclooxygenase (COX)-2 protein in preneoplastic and neoplastic lung lesions induced by the administration of 2000 ppm of N-nitrosobis(2-hydroxypropyl)amine (BHP) in the drinking water to Wistar male rats, was examined immunohistochemically. The majority of alveolar/bronchiolar adenomas (ADs) and all adenocarcinomas (ADCs) examined, stained positive or strongly positive for COX-2. In contrast, only a minority of alveolar/bronchiolar hyperplasias demonstrated immunoreactivity and half of the squamous cell carcinomas examined, were only weakly positive. Western blotting analysis also revealed expression of COX-2 protein in the resected ADs and ADCs. These results clearly indicate up-regulated expression of COX-2 in lung neoplastic lesions, particularly ADs and ADCs, induced by BHP in rats.