Precise Spectroscopy of the 3n and 3p Systems via the

To search for low-energy resonant structures in isospin T=3/2 three-body systems, we have performed the experiments ^{3}H(t,^{3}He)3n and ^{3}He(^{3}He,t)3p at intermediate energies. For the 3n experiment, we have newly developed a thick Ti-^{3}H target that has the largest tritium thickness among targets of this type ever made. The 3n experiment for the first time covered the momentum-transfer region as low as 15 MeV/c, which provides ideal conditions for producing fragile systems. However, in the excitation-energy spectra we obtained, we did not observe any distinct peak structures. This is in sharp contrast to tetraneutron spectra. The distributions of the 3n and 3p spectra are found to be similar, except for the displacement in energy due to Coulomb repulsion. Comparisons with theoretical calculations suggest that three-body correlations exist in the 3n and 3p systems, although not enough to produce a resonant peak.

Epstein-Barr virus reactivation by persistent apical periodontal pathogens.

AIM: To assess whether Epstein-Barr virus (EBV) reactivation is triggered by persistent apical periodontitis-related microbes using in vitro and ex vivo methodologies. METHODOLOGY: Surgically removed human periapical granulomas (n = 50) and healthy gingival tissues (n = 10) were analysed to determine the presence of EBV and seven persistent apical periodontitis-related microbes. In addition, real-time polymerase chain reaction was used to detect the mRNA expression of BZLF-1, an immediate-early gene of EBV. Expression of latent membrane protein (LMP)-1 and ZEBRA, an early lytic protein of EBV encoded by BZLF-1, was also examined using triple-colour immunofluorescence staining. n-Butyric acid produced by the microbes was quantified, and luciferase assays were performed in association with bacterial lysates. In addition, Daudi cells were cultured with bacterial lysates, and the expression levels of BZLF-1 mRNA and ZEBRA protein were determined. RESULTS: EBV DNA and BZLF-1 mRNA were detected in 47 out of 50 periapical granulomas, but not in healthy gingival tissues. The EBV DNA copy number and the number of Fusobacterium nucleatum were significantly positively correlated with BZLF-1 expression in periapical granulomas. The number of Prevotella intermedia was slightly correlated with BZLF-1 expression; however, the other microbes were not. CD79a-positive B cells in periapical granulomas, but not those in healthy gingival tissues, expressed both LMP-1 and ZEBRA. n-Butyric acid production was the highest in F. nucleatum and the lowest in P. intermedia. Enterococcus faecalis, Candida albicans and the other tested microbes did not produce n-butyric acid. An F. nucleatum lysate exhibited significantly increased BZLF-1-luciferase activity in the same manner of commercial butyric acid, whereas P. intermedia did not. F. nucleatum also induced the expression of BZLF-1 mRNA and ZEBRA protein by Daudi cells, indicating that EBV reactivation was induced. CONCLUSION: Among the persistent apical periodontitis-related bacteria that were tested, F. nucleatum most strongly reactivated latent EBV, whereas E. faecalis and C. albicans as well as the other microbes did not.

A potential role for the silent information regulator 2 homologue 1 (SIRT1) in periapical periodontitis.

AIM: To investigate the role played by silent information regulator 2 homologue 1 (SIRT1) during angiogenesis of periapical periodontitis. METHODOLOGY: Periapical granulomas were subjected to dual-colour immunofluorescence imaging and real-time polymerase chain reactions assaying the expression levels of SIRT1, vascular endothelial growth factor (VEGF) and VE-cadherin. The association between Ki-67 and SIRT1 expression was also examined. Human umbilical vein endothelial cells (HUVECs) were treated with a combination of lipopolysaccharide and resveratrol (a SIRT1 activator) or sirtinol (a SIRT1 inhibitor); and the levels of mRNAs encoding SIRT1, VEGF and VE-cadherin were determined. HUVEC tube formation was assayed in the presence of resveratrol or sirtinol. The Mann-Whitney U-test or the Tukey-Kramer test was used for statistical analysis. RESULTS: Ki-67-expressing cells, including endothelial cells, lay adjacent to SIRT1-expressing cells in periapical granulomas. In addition, SIRT1-expressing cells were detected adjacent to VEGF-expressing cells and VEGF- or VE-cadherin-expressing endothelial cells. SIRT1, VEGF and VE-cadherin mRNA expression levels in periapical granulomas were significantly higher (P = 0.0054, 0.0090 and 0.0090, respectively) than those in healthy gingival tissues. HUVECs treated with resveratrol exhibited significantly higher expression of mRNAs encoding SIRT1, VEGF and VE-cadherin (P = 0.0019, 0.00005 and 0.0045, respectively) compared with controls, but sirtinol inhibited such expression. Resveratrol caused HUVECs to form tube-like structures, whilst sirtinol inhibited this process. CONCLUSIONS: These findings suggest that SIRT1 may stimulate angiogenesis in periapical granulomas by triggering the proliferation of endothelial cells and inducing VEGF and VE-cadherin expression.

Porphyromonas endodontalis reactivates latent Epstein-Barr virus.

AIM: To determine whether Porphyromonas endodontalis can reactivate latent Epstein-Barr virus (EBV). METHODOLOGY: The concentrations of short-chain fatty acids (SCFAs) in P. endodontalis culture supernatants were determined using high-performance liquid chromatography. A promoter region of BamHI fragment Z leftward open reading frame 1 (BZLF-1), which is a transcription factor that controls the EBV lytic cycle, was cloned into luciferase expression vectors. Then, the luciferase assay was performed using P. endodontalis culture supernatants. Histone acetylation using Daudi cells treated with P. endodontalis culture supernatants was examined using Western blotting. BZLF-1 mRNA and BamHI fragment Z EB replication activator (ZEBRA) protein were also detected quantitatively using real-time polymerase chain reaction (PCR) and Western blotting. Surgically removed periapical granulomas were examined to detect P. endodontalis, EBV DNA, and BZLF-1 mRNA expression using quantitative real-time PCR. Statistical analysis using Steel tests was performed. RESULTS: The concentrations of n-butyric acid in P. endodontalis culture supernatants were significantly higher than those of other SCFAs (P = 0.0173). Using B-95-8-221 Luc cells treated with P. endodontalis culture supernatants, the luciferase assay demonstrated that P. endodontalis induced BZLF-1 expression. Hyperacetylation of histones was also observed with the culture supernatants. BZLF-1 mRNA and ZEBRA protein were expressed by Daudi cells in a dose-dependent manner after the treatment with P. endodontalis culture supernatants. P. endodontalis and BZLF-1 in periapical granulomas were also detected. The expression levels of BZLF-1 mRNA were similar to the numbers of P. endodontalis cells in each specimen. CONCLUSIONS: n-butyric acid produced by P. endodontalis reactivated latent EBV.

Continuous monitoring of jugular bulb oxygen saturation as a measure of the shunt flow of cerebral arteriovenous malformations.

Jugular bulb oxygen saturation (SjO2) was monitored during preoperative embolization procedures in a consecutive series of 15 patients with large supratentorial arteriovenous malformations (AVM's) in order to test the hypothesis that changes in the shunt flow ratio can be continuously evaluated from the SjO2. A fiberoptic catheter was placed at the dominant jugular bulb. The SjO2 measured using jugular blood withdrawn before embolization was significantly higher than the SjO2 measured at the end of the final embolization procedure (mean +/- standard deviation 84.1% +/- 12.7% vs. 74.2% +/- 10.9%, p < 0.0001), showing a positive correlation with the AVM volume (r = 0.66, p < 0.001). Continuous monitoring of SjO2 via the fiberoptic catheter revealed a progressive decrease in association with the embolization procedures. Microsurgical resection of the AVM was performed at 1 to 2 weeks after the final embolization. Cases in which postoperative hemispheric deformation was revealed on computerized tomography demonstrated a higher SjO2 at the end of embolization compared to that in the remaining cases (81.6% +/- 8.6% vs. 67.8% +/- 8.4%, p < 0.008). Hemispheric deformation was observed in all cases in which the SjO2 did not decline to a level below 90% following embolization. The risk of severe hyperemic complications appeared to be greatly diminished when the SjO2 fell to below 80%. Assuming that the oxygen saturation of the perfusion flow (SjpO2) ranges from 50% to 75%, the ratio of the shunt flow to total flow at an SjO2 of 90% was estimated to be 0.6 to 0.8 based on the following equation: shunt flow/(perfusion flow + shunt flow) = (SjO2 - SjpO2)/(arterial oxygen saturation - SjpO2). These results suggest that monitoring the SjO2 provides real-time information concerning the progress of embolization and helps to determine whether the embolization has progressed sufficiently to avoid postoperative hyperemic complications.

Growth of a giant aneurysm following complete thrombosis by detachable balloon occlusion.

A giant basilar artery aneurysm demonstrating growth and causing neurological deterioration even after complete detachable balloon occlusion is reported. Autopsy revealed total thrombosis of the aneurysm and a hemiconcentric, onion skin-like, laminated structure. Numerous vascular channels and multiple fresh intramural hemorrhages were noted within the outer margin of the aneurysmal wall. Repeated intramural hemorrhages appeared to have been responsible for the aneurysmal laminated structure and contributed to progressive aneurysmal growth. This case demonstrates that the growth of some giant aneurysms is not dependent upon the continuity with the parent artery, and progressive enlargement cannot always be prevented by balloon occlusion.

Use of digital subtraction fluoroscopy to diagnose radiolucent aspirated foreign bodies in infants and children.

OBJECTIVES: Most tracheobronchial foreign bodies in children are radiolucent, and accurate diagnosis of such foreign bodies is not always easy. This can result in delay of diagnosis or misdiagnosis of foreign body aspiration. We report the usefulness and pitfalls of use of digital subtraction fluoroscopy (DSF) to diagnose radiolucent aspirated foreign bodies in infants. METHODS: From 1991 through 1999, DSF was conducted for a total of 19 patients (ranged from 11 months to 4 years and 7 months in age (mean 1.8+/-0.9 years)) who were suspected to have radiolucent aspirated foreign bodies. Since DSF revealed abnormal findings in a trachea or main bronchus in 18 cases, inspection was performed for foreign body bronchofiberscopically. In the one remaining case, no abnormality was recognized on DSF, but since the symptoms at the time of onset strongly suggested aspirated foreign body, bronchofiberscopy was also performed. RESULTS: Foreign body was verified bronchoscopically in 13 of 19 cases, and all 13 (100%) had abnormal findings on DSF, including obstruction of the trachea in two, obstruction of the bronchial lumen in nine, and indistinct visualization of the bronchial lumen in two. Bronchial stenosis was verified bronchoscopically in five of the remaining six cases, including mucus plug in three, granuloma in one and mucosal edema in one case. All five patients (100%) had abnormal findings on DSF, including obstruction of the bronchial lumen in four and indistinct visualization of the bronchial lumen in one. In the one remaining patient with normal findings of DSF, no foreign body or pathological bronchial changes were noted. CONCLUSIONS: DSF was very sensitive in the diagnosis of foreign body aspiration and stenotic changes in the bronchial lumen. However, its diagnostic specificity for aspirated foreign body itself was not high (17%). Therefore, when abnormalities are found on DSF, we recommend to perform flexible bronchofiberscopy initially under general anesthesia via a tracheal tube. When a foreign body is verified, rigid ventilation bronchoscopy is successively performed to retrieve the foreign body.

Embolization of intramedullary spinal arteriovenous malformation fed by the anterior spinal artery with monitoring of the corticospinal motor evoked potential--case report.

Intramedullary spina AVMs fed by the anterior spinal artery cannot be embolized without risking unacceptable motor deficits, since the feeding arteries may supply the corticospinal tract (CST). An 8-year-old boy underwent successful embolization of such an AVM under general anesthesia using intermittent infusion of embolic material with monitoring of the CST integrity with the corticospinal motor evoked potential (MEP). This case illustrates the value of corticospinal MEP monitoring during therapeutic procedures under general anesthesia which risk interrupting the blood supply to the CST.

[A case of penicillin-resistant pneumococcal meningitis and antibiotic susceptibility of Streptococcus pneumoniae isolated from children].

Recently, isolation of penicillin-resistant S. pneumoniae has been increasing. The first Japanese case of penicillin-resistant pneumococcal meningitis was reported in 1988. We experienced a case of a one-year-old boy with penicillin-resistant pneumococcal meningitis who dead on arrival on his third day of illness. Minimal inhibitory concentration (MIC) of penicillin G or S. pneumoniae isolated from cerebrospinal fluid and blood was 0.6 micrograms/ml. We evaluated the antibiotic susceptibility of 163 strains of S. pneumoniae isolated from children from 1985 to 1988. Penicillin G (PCG), ampicillin (ABPC), cefotaxime (CTX), imipenem (IPM), and vancomycin (VCM) had good susceptibilities to S. pneumoniae. Twelve of the 163 isolates (7.3%) were penicillin-resistant strains whose MIC of PCG were more than 0.1 microgram/ml, and all of them were intermediately resistant. The annual penicillin-resistant rates were 12.5% in 1985, 1.3% in 1986, 0% in 1986, and 19.0% in 1988. We also evaluated the MIC distribution and MIC90 of antibiotics available for meningitis against penicillin-sensitive and -resistant S. pneumoniae. MIC90 of PCG and ABPC against penicillin-resistant strains was 1.56 micrograms/ml, and it might be dangerous to use PCG or ABPC for central nervous system pneumococcal infections. MIC90 of IPM against penicillin-resistant strains was 0.1 microgram/ml, and that of VCM was 0.4 micrograms/ml. There was little fall of susceptibilities of resistant strains in IPM and VCM. We evaluated the MIC distribution and MIC70 of antibiotics for oral usage against penicillin-sensitive and -resistant S. pneumoniae. Although there were falls of susceptibilities of resistant strains in PCG and ABPC, these two antibiotics had the best susceptibilities among the oral antibiotics.

[Fundamental and clinical studies of ceftazidime in the field of pediatrics].

We have studied ceftazidime (CAZ), a cephem antibiotic of the new generation, for its antibacterial activity against H. influenzae and clinical effects. Antibacterial activity: MICs of CAZ for 142 strains of H. influenzae including 11 ABPC-resistant strains which were clinically isolated, were determined, and the results were good for all the strains. Clinical effects: CAZ was administered to 9 children with infections. Suspected causative organisms were H. influenzae, E. coli, P. aeruginosa, group B Streptococcus and S. pneumoniae. Eradication of these organisms was confirmed in all the strains except for one in which the antibacterial effect of CAZ was unknown. Clinical efficacy was excellent or good in all the cases. No side effect was observed except for eosinophilia noted in 1 case.

[Clinical studies of sulbactam/cefoperazone therapy in pediatric bacterial infections].

Sulbactam/cefoperazone (SBT/CPZ) was administered intravenously to 9 patients with respiratory infections (H. influenzae 6 cases, pathogens unknown 3 cases), 2 patients with urinary tract infection (E. coli and C. freundii; both cases had VUR), and 1 patient with staphylococcal bacteremia. In these causative bacteria, 5 strains (H. influenzae 3, E. coli 1 and S. aureus 1) were beta-lactamase producers. Bacteriological efficacy (eradication rate) was complete (9/9, 100%) and clinical efficacy was also complete (12/12, 100%). In comparison with CPZ alone, MICs of SBT/CPZ against beta-lactamase producing bacteria were superior. Although mild side effect was observed in 1 case (eosinophilia), no other severe form of adverse reaction were encountered. It was concluded that SBT/CPZ was an useful antibiotic for the treatment of pediatric bacterial infections, especially caused by beta-lactamase (penicillinase) producing bacteria.

[Clinical evaluation of cefpiramide in 6 cases of infection in children].

Cefpiramide (CPM) was given to 4 patients with respiratory tract infection (H. influenzae 3 cases, P. aeruginosa 1 case), 1 patient with enteritis (enteropathogenic E. coli) and 1 patient with sepsis (E. cloacae). Bacteriological eradication was observed in 5 cases (83.3%), and clinical effectiveness was 66.7%. Serum concentration of CPM at a dose of 15 mg/kg after intravenous drip-infusion for 30 minutes was 105 micrograms/ml at the end of infusion and 67 micrograms/ml at 1 hour. Bacteriological eradication by the administration of CPM was rapidly occurred in 3 strains of H. influenzae including 1 strain of beta-lactamase producing ABPC-resistant one, and 1 strain of P. aeruginosa in the sputum. One patient aged 2 years and 5 months with pneumonia was cured by the treatment of CPM as an outpatient. No side effects were observed except 1 case of vascular pain. It was concluded that CPM is a useful drug for the treatment of bacterial infections in children.

[Effects of uro-angiographic contrast media on blood coagulation--a scanning electron microscopic study on time dependent changes of blood clot and a clinical study].

Anticoagulant activity of ionic and nonionic contrast media (CM) was investigated in vitro and in vivo. Based on the time course of FPA and TAT generations and gross examinations of the blood clots on the catheters placed in CM-blood mixtures [an 2 to 8 ratio (20% v/v)]. It was demonstrated that blood coagulation was activated during the period of 20 to 30 minutes when nonionic CM (iopamidol, iohexol) was employed, but no activation of blood coagulation was noted with ionic CM (diatrizoate, ioxaglate). Scanning electron microscopic examinations of the clots on the catheters revealed that fine fibrin meshwork fibers, in which many red blood cells were trapped in bound, were observed with nonionic CM. In contrast, no fibrin mesh was formed with ionic CM after 30 minutes. In vivo, antithrombin III and fibrinogen significantly decreased in the patients who underwent infusion of nonionic CM. Our studies confirmed that nonionic CM show weaker anticoagulant activity than do ionic CM. And these findings account for previous reported thromboembolic complications with the use of nonionic CM. Extreme caution should be therefore exercised when nonionic CM are employed during prolonged angiographic and interventional procedures.

[Effects of ionic and nonionic contrast media on the blood coagulation system, the fibrinolytic system and platelets].

Effects of ionic and nonionic contrast media (CM) on blood coagulation, fibrinolytic system and platelet function were comparatively studied in vitro. By the gross observation of blood coagulation using mixture 2:8 of each contrast media and blood, its total coagulation time was clearly short with iopamidol and iohexol, and no complete coagulation was observed with ioxaglate and diatrizoate for 180 minutes. Anticoagulant effects of all CM were confirmed by the assays of APTT, PT, thrombin time, antithrombin III, FPA, TAT and anti-Xa activity. But, the ionic high osmolar CM (diatrizoate) and low osmolar CM (ioxaglate) showed a greater anticoagulant effect than nonionic CM. Anticoagulant effect of CM on coagulation system may be mainly caused by antithrombin effect. No effects of CM on the fibrinolytic system were observed by assays of the D-dimer, plasminogen and antiplasmin. And all the contrast media produced inhibitory effects of platelet aggregation induced by ADP. Ionic CM tended to have a little stronger inhibitory effect than non-ionic CM. In conclusion, it was suggested that a greater anticoagulant effect of ioxaglate ensures potential safety for thromboembolic complication during angiographic procedure.

Intraparenchymal blood-fluid levels in traumatic intracerebral haematomas.

Blood-fluid levels within the cerebral parenchyma are observed more frequently on CT and MRI in traumatic intracerebral haematomas than in those of other aetiologies. The intraparenchymal blood-fluid interface can be formed without a fluid cavity. It is suggested that the blood-fluid levels represent layering of red blood cells within areas of contusion necrosis as well as extensive contusion oedema. The more extensive the damage to brain tissue, the more often blood-fluid levels formed. A poorer outcome can be therefore predicted when an intraparenchymal blood-fluid interface is seen.