A ribonucleotide reductase gene involved in a p53-dependent cell-cycle checkpoint for DNA damage

The p53 gene is frequently inactivated in human cancers. Here we have isolated a p53-inducible gene, p53R2, by using differential display to examine messenger RNAs in a cancer-derived human cell line carrying a highly regulated wild-type p53 expression system. p53R2 contains a p53-binding sequence in intron 1 and encodes a 351-amino-acid peptide with striking similarity to the ribonucleotide reductase small subunit (R2), which is important in DNA synthesis during cell division. Expression of p53R2, but not R2, was induced by ultraviolet and gamma-irradiation and adriamycin treatment in a wild-type p53-dependent manner. Induction of p53R2 in p53-deficient cells caused G2/M arrest and prevented cells from death in response to adriamycin. Inhibition of endogenous p53R2 expression in cells that have an intact p53-dependent DNA damage checkpoint reduced ribonucleotide reductase activity, DNA repair and cell survival after exposure to various genotoxins. Our results indicate that p53R2 encodes a ribonucleotide reductase that is directly involved in the p53 checkpoint for repair of damaged DNA. The discovery of p53R2 clarifies a relationship between a ribonucleotide reductase activity involved in repair of damaged DNA and tumour suppression by p53.

The Cognitive Abilities Screening Instrument (CASI): a practical test for cross-cultural epidemiological studies of dementia

The Cognitive Abilities Screening Instrument (CASI) has a score range of 0 to 100 and provides quantitative assessment on attention, concentration, orientation, short-term memory, long-term memory, language abilities, visual construction, list-generating fluency, abstraction, and judgment. Scores of the Mini-Mental State Examination, the Modified Mini-Mental State Test, and the Hasegawa Dementia Screening Scale can also be estimated from subsets of the CASI items. Pilot testing conducted in Japan and in the United States has demonstrated its cross-cultural applicability and its usefulness in screening for dementia, in monitoring disease progression, and in providing profiles of cognitive impairment. Typical administration time is 15 to 20 minutes. Record form, manual, videotape of test administration, and quizzes to qualify potential users on the administration and scoring of the CASI are available upon request.

HPLC method for evaluation of the free radical-scavenging activity of foods by using 1,1-diphenyl-2-picrylhydrazyl

An HPLC method for evaluation of the free radical-scavenging activity of foods by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) is reported. The activity was evaluated by measuring the decrease of DPPH detected at 517 nm. By using this novel method, we determined the free radical-scavenging activity of several antioxidants: ascorbic acid, alpha-tocopherol, Trolox, and cysteine. The results gave good correlation between the radical-scavenging activity determined by HPLC and by conventional colorimetry. This methodology was applied to determine the free radical-scavenging activity of 8 beverages. The activity of coffee was the highest, followed by red wine, green tea, oolong tea, black tea, rosé wine, white wine, and orange juice. The results well agree with those of previous reports. This method is expected to be useful for a simple and rapid determination of free radical-scavenging activity in colored foods, because coloring substances in foods do not interfere with the measurement.

Two signals are necessary for cell proliferation induced by a cytokine receptor gp130: involvement of STAT3 in anti-apoptosis

gp130 is a common signal transducer for the interleukin-6-related cytokines. To delineate the gp130-mediated growth signal, we established a series of pro-B cell lines expressing chimeric receptors composed of the extracellular domain of the granulocyte colony-stimulating factor receptor and the transmembrane and cytoplasmic domains of gp130. The second tyrosine (from the membrane) of gp130, which was required for the tyrosine phosphorylation of SHP-2, its association with GRB2, and activation of a MAP kinase, was essential for mitogenesis, but not for anti-apoptosis. On the other hand, the tyrosine in the YXXQ motifs essential for STAT3 activation was required for bcl-2 induction and anti-apoptosis. Furthermore, dominant-negative STAT3 inhibited anti-apoptosis. These data demonstrate that two distinct signals, mitogenesis and anti-apoptosis, are required for gp130-induced cell growth and that STAT3 is involved in anti-apoptosis.

Bruxism physiology and pathology: an overview for clinicians

Awake bruxism is defined as the awareness of jaw clenching. Its prevalence is reported to be 20% among the adult population. Awake bruxism is mainly associated with nervous tic and reactions to stress. The physiology and pathology of awake bruxism is unknown, although stress and anxiety are considered to be risk factors. During sleep, awareness of tooth grinding (as noted by sleep partner or family members) is reported by 8% of the population. Sleep bruxism is a behaviour that was recently classified as a 'sleep-related movement disorder'. There is limited evidence to support the role of occlusal factors in the aetiology of sleep bruxism. Recent publications suggest that sleep bruxism is secondary to sleep-related micro-arousals (defined by a rise in autonomic cardiac and respiratory activity that tends to be repeated 8-14 times per hour of sleep). The putative roles of hereditary (genetic) factors and of upper airway resistance in the genesis of rhythmic masticatory muscle activity and of sleep bruxism are under investigation. Moreover, rhythmic masticatory muscle activity in sleep bruxism peaks in the minutes before rapid eye movement sleep, which suggests that some mechanism related to sleep stage transitions exerts an influence on the motor neurons that facilitate the onset of sleep bruxism. Finally, it remains to be clarified when bruxism, as a behaviour found in an otherwise healthy population, becomes a disorder, i.e. associated with consequences (e.g. tooth damage, pain and social/marital conflict) requires intervention by a clinician.

Ebselen in acute ischemic stroke: a placebo-controlled, double-blind clinical trial. Ebselen Study Group

BACKGROUND AND PURPOSE

The effect of ebselen, a seleno-organic compound with antioxidant activity through a glutathione peroxidase-like action, on the outcome of acute ischemic stroke was evaluated in a multicenter, placebo-controlled, double-blind clinical trial.

METHODS

Patients diagnosed as having acute ischemic stroke who could receive drug treatment within 48 hours of stroke onset were enrolled. Oral administration of ebselen granules suspended in water (150 mg BID) or placebo was started immediately after admission and was continued for 2 weeks. The major end points were the Glasgow Outcome Scale scores at 1 month and 3 months after the start of treatment. The modified Mathew Scale and modified Barthel Index scores at 1 month and 3 months were also studied as secondary outcome measures.

RESULTS

Three hundred two patients were enrolled in the trial. Intent-to-treat analysis of 300 patients (151 given ebselen and 149 given placebo) revealed that ebselen treatment achieved a significantly better outcome than placebo at 1 month (P = .023, Wilcoxon rank sum test) but not at 3 months (P = .056, Wilcoxon rank sum test). The improvement was significant in patients who started ebselen within 24 hours of stroke onset but not in those who started treatment after 24 hours. There was a corresponding improvement in the modified Mathew Scale and modified Barthel Index scores.

CONCLUSIONS

Early treatment with ebselen improved the outcome of acute ischemic stroke. Ebselen may be a promising neuroprotective agent.

Enlargement of spontaneous intracerebral hemorrhage. Incidence and time course

BACKGROUND AND PURPOSE

Standard radiographic criteria for hematoma enlargement have not been established. We undertook this investigation to assess the incidence and time course of hematoma growth using objective cutoff values.

METHODS

We reviewed the clinical records of 204 patients with spontaneous intracerebral hemorrhage treated nonsurgically who underwent initial computed tomography (CT) within 48 hours and repeat CT within 120 hours of the onset of symptoms. The consensus of five observers reading the CT films was considered the "gold standard" for hematoma enlargement. The discriminant values of the difference (V2-V1) or the ratio (V2/V1) of the hematoma volume on the initial (V1) and second (V2) CT scans were determined by use of receiver operating characteristic curves. We chose the cutpoint that had the highest sensitivity and specificity for identifying hematoma expansion.

RESULTS

The cutpoint for hematoma enlargement was determined as V2-V1 = 12.5 cm3 or V2/V1 = 1.4 (sensitivity = 94.4%, specificity = 95.8%). Forty-one patients (20%) had changes that exceeded these criteria. Frequency of hematoma expansion was greatest among those who underwent the initial CT scan early (27 [36%] of 74 patients at < or = 3 hours) and progressively declined as the time to initial scan was prolonged (7 [16%] of 45 patients at 3 to 6 hours; 5 [15%] of 33 patients at 6 to 12 hours; 2 [6%] of 34 patients at 12 to 24 hours; and 0 [0%] of 18 patients at 24 to 48 hours).

CONCLUSIONS

The enlargement of hematoma was defined radiographically as the increase of its volume by > or = 12.5 cm3 or by > or = 1.4 times. Although expansion of intracerebral hemorrhage on CT scan was common in the hyperacute stage, 17% of hematoma expansion occurred even after 6 hours of onset. Enlargement after 24 hours of onset seems extremely rare. Early CT scanning appears to increase the rate of detection of enlarging hematomas.

Intravascular ultrasound-guided optimized stent deployment. Immediate and 6 months clinical and angiographic results from the Multicenter Ultrasound Stenting in Coronaries Study (MUSIC Study)

OBJECTIVES

A study was set up to validate the safety and feasibility of intravascular ultrasound-guided stenting without subsequent anticoagulation, and its impact on the 6 months restenosis rate.

METHODS

The study was designed to be multicentred, prospective, and observational.

RESULTS

One hundred and sixty-one patients with stable angina and a de novo coronary artery lesion were enrolled. In four patients, the implantation of a Palmaz-Schatz (with spiral bridge) stent had failed. One of these four patients died 3 days following bypass surgery. In two other patients, intravascular ultrasound assessment was not performed. One hundred and twenty-five of the remaining 155 patients (81%) were treated with aspirin (100 mg x day(-1)), because all three criteria for optimized stent expansion were met. Twenty-two of the remaining 38 patients (25%), in whom at least one criterion was not met were treated with aspirin and acenocoumarol (3 months, INR 2.5-3.5), while 16 patients only received aspirin. Stent thrombosis was documented in two patients (1.3%) for which repeat angioplasty was performed. During the hospital stay, there were no deaths or Q-wave myocardial infarctions. Five patients (3.2%) sustained a non-Q-wave myocardial infarction. During the follow-up period (198+/-38 days, complete for all patients, except one), one patient (0.6%) sustained a Q-wave myocardial infarction, one (0.6%) underwent bypass surgery, and repeat angioplasty was performed in nine patients (5.7%). In two of the nine patients, repeat angioplasty involved another lesion. Therefore, the target lesion revascularization rate during follow-up was 4.5% (seven patients). At quantitative coronary angiography, the minimal lumen diameter (mean+/-SD) increased from 1.12+/-0.34 mm before to 2.89+/-0.35 mm after stenting. Repeat angiography at 6 months was performed in 144 patients (92%). The minimal lumen diameter at follow-up was 2.12+/-0.67 mm. Restenosis (diameter stenosis of 50% or more) was documented in 12 patients or 8.3%. When the two patients with documented stent thrombosis are included, the restenosis rate amounts to 97%.

CONCLUSIONS

These data confirm that, in selected patients, stents can safely be implanted without the use of systemic anticoagulation, provided optimal stent expansion is achieved. The exact role of intravascular ultrasound in the achievement of these results needs to be established by appropriately designed studies. In the meantime, intravascular ultrasound coupled with the Palmaz-Schatz stent incorporating a spiral bridge, may have contributed considerably to the immediate angiographic outcome, which in turn may explain the favourable clinical and angiographic outcome at 6 months.

Laparoscopic and endoscopic cooperative surgery for gastrointestinal stromal tumor dissection

BACKGROUND

Laparoscopic wedge resections are increasingly applied for gastric submucosal tumors such as gastrointestinal stromal tumor (GIST). Despite this, no defined strategy exists to guide the surgeon in choosing the appropriate laparoscopic technique for an individual case on the basis of tumor characteristics such as location or size. This study aimed to introduce a laparoscopic and endoscopic cooperative surgery (LECS) for gastric wedge resection that is applicable for submucosal tumor resection independent of tumor location and size.

METHODS

Seven patients underwent LECS for the resection of gastric submucosal tumors. Both mucosal and submucosal layers around the tumor were circumferentially dissected using endoscopic submucosal dissection via intraluminal endoscopy. Subsequently, the seromusclar layer was laparoscopically dissected on the exact three-fourths cut line around the tumor. The submucosal tumor then was exteriorized to the abdominal cavity and dissected with a standard endoscopic stapling device.

RESULTS

In all cases, the LECS procedure was successful for dissecting out the gastric submucosal tumor. In four of seven cases, the tumor was located in the upper gastric portion near the esophagogastric junction. The remaining three tumors were in the posterior gastric wall. In two cases, the tumors were more than 5 cm in diameter, and one was a GIST of the remnant stomach. The mean operation time was 169 +/- 17 min, and the estimated blood loss was 7 +/- 2 ml. The postoperative course was uneventful in all cases.

CONCLUSIONS

The LECS procedure for dissection of gastric submucosal tumors such as GIST may be performed safely with reasonable operation times, less bleeding, and adequate cut lines. In addition, the success of the procedure does not depend on the tumor location such as the vicinity of the esophagogastric junction or pyloric ring.

The effects of 5-minute ischemia in Mongolian gerbils: II. Changes of spontaneous neuronal activity in cerebral cortex and CA1 sector of hippocampus

Spontaneous neuronal activity was recorded in the cerebral cortex and the CA1 sector of the hippocampus in gerbils during and after 5-min ischemia, produced by bilateral clamping of the common carotid arteries. It was found that spontaneous activity in both cortical and CA1 neurons ceased within 60s after the onset of ischemia and that it began to reappear 10-20 min after the recirculation. During the next 24 h most CA1 neurons which were recorded showed hyperactivity. This was evident primarily by an increase in spike discharges, whereas recordings from the cerebral cortex were within the preocclusion ranges. On the 2nd day after ischemia, functioning CA1 neurons could not be found, as if they were in a state of functional death, although histological sections showed a general preservation of their cellular structure at that time.

The Arabidopsis HKT1 gene homolog mediates inward Na(+) currents in xenopus laevis oocytes and Na(+) uptake in Saccharomyces cerevisiae

The Na(+)-K(+) co-transporter HKT1, first isolated from wheat, mediates high-affinity K(+) uptake. The function of HKT1 in plants, however, remains to be elucidated, and the isolation of HKT1 homologs from Arabidopsis would further studies of the roles of HKT1 genes in plants. We report here the isolation of a cDNA homologous to HKT1 from Arabidopsis (AtHKT1) and the characterization of its mode of ion transport in heterologous systems. The deduced amino acid sequence of AtHKT1 is 41% identical to that of HKT1, and the hydropathy profiles are very similar. AtHKT1 is expressed in roots and, to a lesser extent, in other tissues. Interestingly, we found that the ion transport properties of AtHKT1 are significantly different from the wheat counterpart. As detected by electrophysiological measurements, AtHKT1 functioned as a selective Na(+) uptake transporter in Xenopus laevis oocytes, and the presence of external K(+) did not affect the AtHKT1-mediated ion conductance (unlike that of HKT1). When expressed in Saccharomyces cerevisiae, AtHKT1 inhibited growth of the yeast in a medium containing high levels of Na(+), which correlates to the large inward Na(+) currents found in the oocytes. Furthermore, in contrast to HKT1, AtHKT1 did not complement the growth of yeast cells deficient in K(+) uptake when cultured in K(+)-limiting medium. However, expression of AtHKT1 did rescue Escherichia coli mutants carrying deletions in K(+) transporters. The rescue was associated with a less than 2-fold stimulation of K(+) uptake into K(+)-depleted cells. These data demonstrate that AtHKT1 differs in its transport properties from the wheat HKT1, and that AtHKT1 can mediate Na(+) and, to a small degree, K(+) transport in heterologous expression systems.

Induction of heme oxygenase-1 suppresses venular leukocyte adhesion elicited by oxidative stress: role of bilirubin generated by the enzyme

This study aimed to examine whether an elevated activity of heme oxygenase (HO)-1 in the tissue attenuates endothelial cell-leukocyte interactions microvessels in vivo. When rats were pretreated with an intraperitoneal injection of hemin, an HO-1 inducer, mesenteric tissues, including their microvessels, displayed a marked induction of HO-1 concurrent with an increase in plasma concentrations of bilirubin-IXalpha, the product of HO-catalyzed degradation of protoheme IX. In these rats, oxidative stress such as superfusion with H(2)O(2) and ischemia-reperfusion of the tissues neither induced rolling nor exhibited adherent responses of leukocytes in venules. In contrast, the oxidative stresses evoked marked rolling and adhesion of leukocytes in the control rats without HO-1 induction. The HO-1 induction also downregulated leukocyte adhesion elicited by other pro-oxidant stimuli such as N(omega)-nitro-L-arginine methyl ester. The decreases in the oxidant-elicited leukocyte adhesive responses under HO-1-inducing conditions were restored by perfusion with zinc protoporphyrin-IX, an HO inhibitor, but not with copper protoporphyrin-IX, which did not inhibit the enzyme. Furthermore, the effects of zinc protoporphyrin-IX were repressed by superfusion with bilirubin or biliverdin at the micromolar level, but not by the same concentration of carbon monoxide, another product of HO. These results indicate that induction of the HO-1 activity serves as a potential stratagem to prevent oxidant-induced microvascular leukocyte adhesion through the action of bilirubin, a product of HO reaction.

cAMP stimulates the in vitro proliferation of renal cyst epithelial cells by activating the extracellular signal-regulated kinase pathway

BACKGROUND

: Cellular proliferation is a key factor in the enlargement of renal cysts in autosomal dominant polycystic kidney disease (ADPKD). We determined the extent to which adenosine 3':5'-cyclic monophosphate (cAMP) may regulate the in vitro proliferation of cyst epithelial cells derived from human ADPKD cysts.

METHODS

: Epithelial cells from cysts of individuals with ADPKD and from normal human kidney cortex (HKC) of individuals without ADPKD were cultured. The effects of agonists and inhibitors on the rate of cellular proliferation and the activation of extracellular signal-regulated kinase (ERK1/2) were determined.

RESULTS

: 8-Br-cAMP (100 micromol/L) stimulated the proliferation of cells from eight different ADPKD subjects to 99.0% above baseline; proliferation was inhibited by protein kinase A (PKA) antagonists H-89 (97%) and Rp-cAMP (90%). Forskolin (10 micromol/L), which activates adenylyl cyclase, increased proliferation 124%, and receptor-mediated agonists arginine vasopressin, desmopressin, secretin, vasoactive intestinal polypeptide, and prostaglandin E2 stimulated proliferation 54.2, 56.3, 46.7, 37.1, and 48.3%, respectively. The mitogen extracellular kinase (MEK) inhibitor PD98059 completely inhibited ADPKD cell proliferation in response to cAMP agonists, but genistein, a receptor tyrosine kinase inhibitor, did not block cAMP-dependent proliferation. cAMP agonists increased the activity of ERK above control levels within five minutes. In contrast to ADPKD, proliferation and ERK activity of cells derived from normal HKC were not stimulated by cAMP agonists, although electrogenic Cl- secretion was increased by these agonists in both ADPKD and HKC cell monolayers.

CONCLUSIONS

: We conclude that cAMP agonists stimulate the proliferation of ADPKD but not HKC epithelial cells through PKA activation of the ERK pathway at a locus distal to receptor tyrosine kinase. We suggest that the adenylyl cyclase signaling pathway may have a unique role in determining the rate of cyst enlargement in ADPKD through its actions to stimulate cellular proliferation and transepithelial solute and fluid secretion.

Incidence and prognostic significance of lateral lymph node metastasis in patients with advanced low rectal cancer

BACKGROUND

Lateral lymph node metastases occur in some patients with low rectal cancer and may cause local recurrence after total mesorectal excision. The aims of this study were to identify risk factors for lateral node metastases in patients with pathological tumour (pT) stage 3 or pT4 low rectal adenocarcinoma, and to evaluate the prognostic significance of lateral node metastases.

METHODS

A retrospective analysis was performed of the outcome of 237 patients with pT3 or pT4 low rectal adenocarcinoma who underwent R0 resection with systematic lateral node dissection.

RESULTS

Lateral lymph node metastases were found in 41 patients (17.3 per cent). Increased risk of lateral lymph node metastases was associated with a distal tumour margin close to the anal margin, histological type other than well or moderately differentiated adenocarcinoma, and the presence of mesenteric lymph node metastases. Patients with lateral node metastases had a significantly shorter postoperative survival (5-year survival rate 42 versus 71.6 per cent; P < 0.001) and an increased risk of local recurrence (44 versus 11.7 per cent; P < 0.001) compared with those without lateral node metastases.

CONCLUSION

Tumour site, histological type and the presence of mesenteric lymph node metastasis are factors predicting the risk of lateral node metastasis. The poor prognosis of patients with lateral lymph node metastases after systematic lateral dissection suggests the need for adjuvant therapy.

Proliferative activity of intrahepatic colorectal metastases after preoperative hemihepatic portal vein embolization

Although hemihepatic portal vein embolization (PVE) has been used preoperatively to extend indications for hepatectomy in patients with colorectal metastases, the effects of this procedure on tumor growth and outcome remain controversial. To address this issue, we assessed the proliferative activity of intrahepatic metastases after PVE and the long-term outcome of this procedure. Eighteen patients with colorectal metastases underwent preoperative PVE between 1996 and 2000 (PVE group). Twenty-nine patients who underwent major hepatic resection without PVE served as control (non-PVE group). The hepatic parenchymal fraction of the left lobe had significantly increased from 38.1 +/- 3.2% to 45.9 +/- 2.9% 3 weeks after PVE (+20.5%, P <.0001). Tumor volume and percent tumor volume had also significantly increased from 223 +/- 89 mL to 270 +/- 97 mL (+20.8%, P =.016) and from 13.7 + 4.3% to 16.2 + 4.9% (+18.5%, P =.014), respectively. There was no apparent correlation between the increase in parenchymal volume and that in tumor volume. The Ki-67 labeling index of metastatic lesions was 46.6 +/- 7.2% in the PVE group and 35.4 +/- 12.6% in the non-PVE group (P =.013). Long-term survival was similar in the PVE and non-PVE groups, however, disease-free survival was significantly poorer in the PVE group than in the non-PVE group (P =.004). We conclude that PVE increases tumor growth and probably is associated with enhanced recurrence of disease. Although PVE is effective in extending indications for surgery, patient selection for PVE should be cautious.

Collective review of small carcinomas of the pancreas

To determine problems involved in the treatment and diagnosis of pancreatic cancer, a collective study of small carcinoma of the pancreas (2 cm or less in diameter) was performed. One hundred six cases were collected and analyzed. The results were as follows: In small carcinoma of the pancreas, the resectability rate was 99.0% and the operative mortality rate was 4%. Only 44% of the patients belonged to Stage I, and 14% belonged to Stage III or IV. Lymph node involvement, capsular invasion, retroperitoneal invasion, and vascular invasion were found in 30, 20, 12, and 9% of the patients, respectively. The postoperative cumulative 5-year survival rate was 30.3%, and that of Stage I was 37.0%. A small-sized tumor of the pancreas is not always an early carcinoma, but a tumor in Stage I may be regarded as an early carcinoma. Percutaneous transhepatic cholangiography and endoscopic retrograde cholangiopancreatography were the main diagnostic indicators in cases with and without jaundice, respectively. There was no specific single serum test for detecting small pancreatic cancer.

Control of calcium oscillations by phosphorylation of metabotropic glutamate receptors

Stimulation of two metabotropic glutamate-receptor subtypes, mGluR1 and mGluR5, triggers the release of Ca2+ from intracellular stores through the inositol-(1,4,5) trisphosphate (InsP3) pathway. Here we report that glutamate induces single-peaked intracellular Ca2+ mobilization in mGluR1alpha-transfected cells but elicits Ca2+ oscillations in mGluR5a-transfected cells. The response patterns of the intracellular Ca2+ increase depend upon the identity of a single amino acid, aspartate (at position 854) or threonine (at position 840), located within the G-protein-interacting domains of mGluR1alpha and mGluR5a, respectively. Pharmacological and peptide mapping analyses indicated that phosphorylation of the threonine residue at position 840 of mGluR5a by protein kinase C (PKC) is responsible for the generation of Ca2+ oscillations in mGluR5a-expressing cells. To our knowledge this is the first evidence that PKC phosphorylation of G-protein-coupled receptors is important in producing oscillations in intracellular Ca2+ signalling.

Prevalence and spectrum of germline mutations of the p53 gene among patients with sarcoma

BACKGROUND

Recent studies have identified germline mutations of the p53 tumor-suppressor gene in families with the Li-Fraumeni syndrome, a rare inherited disorder characterized by a high risk of sarcomas of bone and soft tissue, breast cancer, and other tumors. In this report, we address the possibility that some sporadic sarcomas may be associated with new germline mutations of the p53 gene, which would not be manifested as familial cancer unless the patient survived to reproduce.

METHODS

We studied DNA from peripheral leukocytes of 196 patients with sarcoma and from 200 controls. Of the 196 patients with sarcoma, 15 were selected because they had had multiple primary cancers or had a family history of cancer. The entire coding sequence and splice junctions of the p53 gene were analyzed for mutations.

RESULTS

Eight germline mutations were found, three in patients with no known family history of cancer and five in patients with an unusual personal or family history of cancer. Four mutations caused amino acid substitutions, and four caused stop codons. These mutations were not present in any of the 200 controls.

CONCLUSIONS

New germline mutations of the p53 gene are rare among patients with "sporadic" sarcoma but may be common in patients with sarcoma whose background includes either multiple primary cancers or a family history of cancer. Diverse mutations of this gene were associated with an increased likelihood of cancer; hence, the entire gene should be considered a target for heritable mutation. It appears that the group of patients with cancer who carry germline mutations of the p53 gene is more diverse than is suggested by the clinical definition of the Li-Fraumeni syndrome. The identification of carriers could be of substantial clinical importance.

Activation of NADPH oxidase in Alzheimer's disease brains

The present study is the first to show that superoxide (O(-)(2)) forming NADPH oxidase is activated in Alzheimer's disease (AD) brains by demonstrating the marked translocation of the cytosolic factors p47-phox and p67-phox to the membrane. In conjunction with a recent in vitro study showing that amyloid beta activates O(-)(2) forming NADPH oxidase in microglia, where these phox proteins are localized in this study, the present results suggest that, in AD, NADPH oxidase is activated in microglia, resulting in the formation of reactive oxygen species which can be toxic to neighboring neurons in AD.

Chromatographic separation of racemic amino acids by use of chiral crown ether-coated reversed-phase packings

Chromatographic packings for optical resolution of underivatized racemic amino acids were prepared by dynamic coating of a chiral crown ether on reversed-phase packings, and their characteristics were examined. Almost all the amino acids commonly found in proteins were finely separated into their enantiomers when a dilute aqueous solution of perchloric acid was used as the eluent. The enantiomers forming more stable complexes with the chiral crown ether were eluted after those forming less stable complexes. The retention and resolution of racemic amino acids depended on the eluent, the column temperature and the amount of crown ether coated. The separation coefficients, alpha, increased with decreasing column temperature and/or with increasing amount of crown ether coated.

Atrial fibrillation as a predictive factor for severe stroke and early death in 15,831 patients with acute ischaemic stroke

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia and a major risk factor for stroke.

AIMS

To assess whether AF in patients with acute ischaemic stroke is associated with severe stroke and early death.

MATERIALS/METHODS

Patients with acute ischaemic stroke (15,831) who were registered in the Japan Multicenter Stroke Investigators' Collaboration registry were analysed. The AF group comprised 3335 (21.1%) patients (median age, 75 years) and the non-AF group comprised 12,496 (78.9%) patients (median age, 70 years). The association between AF and severe stroke and early death was investigated by means of multivariate logistic regression analysis.

RESULTS

The admission National Institutes of Health Stroke Scale (NIHSS) score of the AF group was higher than that of the non-AF group (median, 12 v 5; p < 0.0001). Multivariate logistic regression analyses found that female sex, advanced age, AF, and a history of stroke were independent factors associated with severe stroke (NIHSS score, > or = 11). The mortality rate within 28 days after admission was 11.3% in the AF group and 3.4% in the non-AF group (p < 0.0001). Multivariate logistic regression analyses identified older age, AF, and NIHSS score at admission as independent factors associated with early death.

CONCLUSION

AF was a predictive factor for severe stroke and early death in acute ischaemic stroke. Careful cardiac evaluation and appropriate treatment are needed to improve outcome in patients with acute stroke and AF.

Neutrophil proteinase 3-mediated induction of bioactive IL-18 secretion by human oral epithelial cells

IL-18, a potent IFN-gamma-inducing cytokine, is expressed by various nonimmune cells as well as macrophages, suggesting that it has important physiological and immunological roles. The present study focused on the mechanism of active IL-18 induction from human oral epithelial cells. The epithelial cells and the cell lines constitutively express IL-18 mRNA and the 24-kDa precursor form of IL-18. Bioactive IL-18 exhibiting IFN-gamma-inducing activity was detected in the supernatant of the cells on costimulation with neutrophil proteinase 3 (PR3) and LPS for 24 h after IFN-gamma-priming for 3 days. An active 18-kDa form of IL-18 was detected in lysate and supernatant of the cells only after the above treatment and the induction was inhibited by cycloheximide and by serine proteinase inhibitors. After the treatment, lactate dehydrogenase activity was not detected in the cell culture supernatant, and PR3 was detected only in the membrane and not in cytoplasm fractions of the cells. Caspase-1 was not detected in the cells even after the treatment and the IL-18 induction was not inhibited by a caspase-1 inhibitor. These results suggest that the PR3-mediated induction of bioactive IL-18 secretion from oral epithelial cells in combination with LPS after IFN-gamma-priming occurred via a caspase-1-independent pathway, and provide new insight into the possible involvement of a neutrophil proteinase in the induction of bioactive IL-18 in oral inflammation such as periodontitis.