Reduced risk of hepatocellular carcinoma after interferon therapy in aged patients with chronic hepatitis C is limited to sustained virological responders

This study was undertaken to investigate the effect of interferon (IFN) monotherapy on the risk of hepatocellular carcinoma (HCC) in aged-patients with chronic hepatitis C. Seven hundred and twenty-five patients with histologically proven chronic hepatitis C were enrolled in this retrospective cohort study; 531 received IFN monotherapy for 6 months between 1992 and 1995, and 157 were collected as a historical control. The effect of IFN therapy on the development of HCC was compared between the patients with chronic hepatitis C under 60 years old (non-aged group, n = 531) and those 60 and over (aged group, n = 194). A stepwise Cox proportional-hazards regression analysis in the non-aged group revealed that IFN therapy (risk ratio 0.52, 95% CI 0.33-0.81, P = 0.004), older age (P = 0.001), and higher histological stage (P < 0.001) were independent factors associated with the development of HCC. In the aged-group, only higher histological stage (P = 0.002) and male gender (P = 0.011), but not IFN therapy (risk ratio 0.77, 95% CI 0.42-1.40, P = 0.386), were identified as independent risk factors for HCC, although HCC was significantly reduced when sustained virological response (SVR) was obtained (risk ratio 0.23, 95% CI 0.08-0.64, P = 0.005). In conclusion, inhibitory effect of IFN on development of HCC in the patients with chronic hepatitis C aged 60 and over was limited to the patients achieving SVR when treated with 6 months-IFN monotherapy.

Altered immunoglobulin A and M levels associated with changes in BAFF and APRIL after administration of intravenous immunoglobulin to treat Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is an acute vasculitis of unknown etiology. Immunoregulatory abnormalities have been thought to contribute to its pathogenesis. Although treatment with intravenous immunoglobulin (IVIG) effectively prevents significant cardiac morbidity, the mechanism by which IVIG produces an effect in KD has yet to be fully elucidated.

OBJECTIVE

To investigate the effects of IVIG on the immune system of patients with KD.

PATIENTS AND METHODS

Eleven patients with KD (mean [SD] age, 2.2 [1.5] years) were enrolled in this prospective study and treated with high-dose IVIG therapy (2 g/kg in 1 or 2 infusions) during the acute phase of the disease. We examined immunological changes, with special reference to Ig levels and 2 previously unassessed cytokines: B cell-activating factor belonging to the tumor necrosis factor family (BAFF), and a proliferation-inducing ligand (APRIL).

RESULTS

Clinical symptoms disappeared quickly in all cases, with no coronary artery abnormalities. IgA and IgM levels responded more rapidly than previously reported and reached a peak between the 3rd and 10th day after the start of IVIG treatment. The mean (SD) BAFF level was high before IVIG treatment (3234 [1904] pg/mL) and decreased significantly (1085 [257] pg/mL) after IVIG treatment, whereas the mean (SD) APRIL level before IVIG treatment (18.0 [10.0] ng/mL) rose significantly (120.6 [41.2] ng/mL). A significant inverse correlation between BAFF and APRIL was observed in patients with KD.

CONCLUSIONS

These results suggest that IVIG may affect the pathogenesis of KD through alteration of BAFF/APRIL.

Prospective Study of Ice Gel Pack as Less Expensive Alternative for Prevention of Skin and Nail Toxicity in Patients with Breast Cancer Receiving Docetaxel

Background: Docetaxel (DTX)-induced nail and skin toxicity can be prevented by frozen glove. We investigate whether we can use cooling gel pad (CGP), which is available less than 10 dollars in Japan, as less expensive alternative.Method: Patients (pts) with breast cancer receiving DTX as preoperative or post operative chemotherapy were eligible for this study. Two CGPs, which were refrigerated for eight hours beforehand, were used to cover patient's hand from 15 minutes before to 15minutes after DTX administration. To reduce discomfort from icing, pts were wearing cotton glove during CGP usage. If pts felt CGP as too cold during the cooling process, they were allowed to remove CGP tentatively until they felt comfort. Another hand was not covered as the control. Nail and skin toxicity were assessed at each cycle by CTCAEver.3.0 and documented by photography. Fisher's exact probability test was used. Satisfaction and discomfort of CGP covering was assessed by pts using two item questionnaires. All patients gave written informed consent. The protocol was approved by institutional review board.Result: From October 2006 to September 2008, 50 pts were enrolled to this study. All the patients were female, and received DTX 75mg/m2 in every three weeks schedule for four cycles. Most of patients received DTX after anthracycline-containing regimen. Both nail (10% v 66%, p&lt;0.0001) and skin (0% v 34%, p&lt;0.0001) toxicity was reduced in CGP covered hands. Nail toxicity was grade (G) 0 in 90% v 34%, G1 in 10% v 42%, G2 in 0% v 22%, and G3 in 0% v 2%, for CGP covered and the control hand, respectively. Skin toxicity was G0 in 100% v 66%, G1 in 0% v 4%, G2 in 0% v 30% in CGP covered hand and the control hand, respectively. About the timing of toxicity occurrence, “after the first cycle” was most common, 13 pts (39%) in nail change and 7 pts (41%) in skin toxicity. In the questionnaires, 94% were satisfied with CGP covering.Discussion: The iced CGP cover method reduced the incidence and severity of nail and skin toxicity associated with DTX, even if patients wear cotton glove and remove CGP for a while, in case of excess coldness. This method has no adverse effect, and patients were satisfied with the effect. The iced CGP may be considered as a new, effective and less expensive method for prevention of nail and skin toxicity caused by DTX.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1114.

Simultaneous genotyping of alcohol dehydrogenase 2 and aldehyde dehydrogenase 2 by single‐strand conformation polymorphism analysis

Alcohol dehydrogenase (ADH; EC 1.1.1.1) and aldehyde dehydrogenase (ALDH; EC 1.2.1.3) have important roles in the elimination of ingested ethanol. These enzymes have polymorphisms resulting from single-point mutations that cause kinetic differences in their respective enzyme activities. Simultaneous observation of these enzymes would be useful in investigating the association between these enzyme polymorphisms and alcohol-related problems. In this study amplified genomic DNA was amplified from nail clippings with two sets of primers for ADH2 and ALDH2 genes, respectively, in a micro test tube and the accuracy of the amplification was verified by direct sequencing. The PCR products were separated into four distinct bands by single-strand conformation polymorphism analysis. This genotyping method is fast, accurate. reliable and inexpensive, and requires the same amount of template DNA as non-simultaneous methods. In other words, the required amount of template DNA for this method is only half that required for the separate genotyping of ADH2 and ALDH2.

Disrupting actin filaments promotes efficient transfection of a leukemia cell line using cell adhesive protein-embedded carbonate apatite particles

Tumor cells such as leukemia and lymphoma cells are obvious and attractive targets for gene therapy. Gene transfer and expression for cytokine and immunomodulatory molecules in various kinds of tumor cells have been shown to mediate tumor regression and antimetastatic effects. Moreover, genetically modified leukemia cells expressing costimulatory molecules or cytokines are likely to have significant therapeutic roles for patients with leukemia. One of the major hurdles to the successful implementation of these promising approaches is the lack of a suitable nanocarrier for transgene delivery and expression in a safe and effective manner. Recently, we reported on the development of a safe, efficient nanocarrier system of carbonate apatite that can assist both intracellular delivery and release of DNA, leading to very high level of transgene expression in cancer and primary cells. However, its efficiency in human lymphocytes is poor. We show here that nanocrystals of carbonate apatite, when electrostatically associated with fibronectin and/or E-cadherin-Fc, accelerated transgene delivery in a human T leukemia cell line (Jurkat). Moreover, transgene expression efficiency could be enhanced dramatically with the cell adhesive protein-embedded particles finally up to 150 times by selectively disrupting the actin filaments.

Assessment of abnormal left atrial relaxation by transesophageal pulsed Doppler echocardiography of pulmonary venous flow velocity

BACKGROUND

Several studies on left ventricular relaxation have been undertaken in the past; however, left atrial (LA) relaxation has not been fully evaluated.

HYPOTHESIS

The purpose of this study was to assess abnormalities in LA relaxation by evaluating pulmonary venous flow velocity and interatrial septal motion using transesophageal echocardiography.

METHODS

The subjects were 56 untreated patients in sinus rhythm, including 25 with previous myocardial infarction, 9 with hypertrophic cardiomyopathy, 11 with dilated cardiomyopathy, as well as 11 with chest pain syndrome as controls. Peak first systolic velocity (PVS1), peak atrial systolic velocity (PVA), and their time-velocity integrals (PVS1-I and PVA-I, respectively) were calculated from the pulmonary venous flow velocity.

RESULTS

The PVS1 and PVS1-I correlated negatively with the maximum LA dimension and mean pulmonary capillary wedge pressure, and correlated positively with the amplitude of the interatrial septal motion during LA relaxation and percent fractional LA relaxation. The PVA and PVA-I did not correlate with the mean pulmonary capillary wedge pressure. There was a weak positive correlation between PVA and PVS1, and a close positive correlation between the ratio of PVA to PVS1 and mean pulmonary capillary wedge pressure. Multiple regression analysis indicated that the PVS1 was most closely related to percent fractional LA relaxation, followed by mean pulmonary capillary wedge pressure.

CONCLUSION

The PVS1 determined from the pulmonary venous flow velocity is closely related to parameters of LA relaxation which may be determined by transesophageal M-mode echocardiography, and the ratio of PVA to PVS1 is useful for noninvasive evaluation of LA pressure.

Evaluation of left atrial filling using systolic pulmonary venous flow velocity measurements in patients with atrial fibrillation

BACKGROUND

The pattern of pulmonary venous flow velocity is useful for understanding the hemodynamic relationship between the left atrium and left ventricle in patients with a variety of diseases, and the systolic flow wave, in particular, is considered a clinically important parameter that reflects left atrial filling.

HYPOTHESIS

The study was undertaken to determine whether systolic pulmonary venous flow velocity patterns can be used to evaluate left atrial filling in patients with atrial fibrillation.

METHODS

We performed transesophageal pulsed Doppler echocardiography and cardiac catheterization in 34 patients with chronic atrial fibrillation (10 with hypertrophic cardiomyopathy, 5 with dilated cardiomyopathy, 7 with previous myocardial infarction, and 12 with isolated atrial fibrillation) and 15 normal controls in sinus rhythm.

RESULTS

Mean pulmonary capillary wedge pressure, V-wave height in the pulmonary capillary wedge pressure curve, and left ventricular end-diastolic pressure were significantly higher in the hypertrophic cardiomyopathy and dilated failing heart (previous myocardial infarction and dilated cardiomyopathy) groups than in the isolated atrial fibrillation and normal groups. The peak velocity and time-velocity integral of the systolic pulmonary venous flow velocity, and percent left atrial emptying fraction were significantly lower in the dilated failing heart group than in the isolated atrial fibrillation, hypertrophic cardiomyopathy, and normal groups. The peak velocity and time-velocity integral of the systolic pulmonary venous flow velocity, percent left atrial emptying fraction, and V-wave height were comparatively constant when the preceding R-R intervals were relatively stable in the isolated atrial fibrillation group and in 4 of the 10 patients with hypertrophic cardiomyopathy. However, changes in these variables correlated with the preceding R-R interval in all patients with dilated failing hearts and in 6 of the 10 patients with hypertrophic cardiomyopathy.

CONCLUSION

Transesophageal pulsed Doppler echocardiographic measurements of systolic pulmonary venous flow velocity are valid indicators of left atrial filling in patients with atrial fibrillation.

Echocardiographic characteristics and causal mechanism of physiologic mitral regurgitation in young normal subjects

BACKGROUND

It has become evident that mitral regurgitation (MR) is not uncommon in healthy subjects, and Doppler color flow mapping is a technique that imparts important information relevant to its detection.

HYPOTHESIS

Using transthoracic echocardiography, this study evaluated the mechanism of physiologic MR in young normal subjects using transthoracic echocardiography.

METHODS

The study population consisted of 48 young normal subjects (mean 21 +/- 5 years) with MR (physiologic MR group), 40 age-matched young normal subjects (mean 20 +/- 5 years) without MR (control group), 45 patients (mean 41 +/- 15 years) with mitral valve prolapse with MR (MVP group), and 27 patients (mean 59 +/- 13 years) with ruptured chordae tendineae (rupture group).

RESULTS

Men were predominant in the rupture group, whereas there were no significant gender differences in the other three groups. Left ventricular end-diastolic dimension and left atrial systolic dimension were slightly smaller in the physiologic MR group than in the control group, but were significantly smaller than those in the MVP and rupture groups. The ratio of the maximum anteroposterior diameter to the maximum transverse diameter on chest radiography and the ratio of the short- to long-axis diameter of the left ventricular cavity at end diastole, determined from two-dimensional short-axis echocardiogram, were significantly lower in the physiologic MR group than in the other three groups. Mitral regurgitation occurred more frequently at the posteromedial commissural site in the physiologic MR and MVP groups, whereas there was no preference for location in the rupture group. Early systolic MR was often observed in the physiologic MR group, whereas pansystolic MR was common in the MVP and rupture groups.

CONCLUSION

As a causal mechanism for physiologic MR detected in young normal subjects, "flattening" of the thorax during growth may cause morphologic abnormalities of the left atrial and ventricular cavities, resulting in spatial imbalance of the mitral complex and resulting in malcoaptation of the valve.

Analgesic requirements after major abdominal surgery are associated with OPRM1 gene polymorphism genotype and haplotype

Aims: The association between SNPs of the human OPRM1 gene encoding the µ-opioid receptor and postoperative analgesic requirements in surgical patients remains controversial. Here, we evaluate whether any of the five tag SNPs (A118G, IVS2+G691C, IVS3+G5953A, IVS3+A8449G and TAA+A2109G) representing the four linkage disequilibrium blocks of the OPRM1 gene influences postoperative analgesic requirements. Materials & methods: We studied 138 adult Japanese patients who underwent major open abdominal surgery under combined general and epidural anesthesia and received continuous postoperative epidural analgesia with opioids. Results: The 118G homozygous (GG) patients required 24-h postoperative analgesics more than 118A homozygous (AA) and heterozygous (AG) patients. Tag SNP haplotypes also were associated with 24-h postoperative analgesic requirements. Conclusions: These results suggest that OPRM1 gene tag SNP genotypes and haplotypes can primarily contribute to prediction of postoperative analgesic requirements in individual patients undergoing major open abdominal surgery.

Inverse correlation between NKG2D expression on CD8+ T cells and the frequency of CD4+CD25+ regulatory T cells in patients with esophageal cancer

Although malignant diseases are known to be associated with immune suppression, detailed mechanisms of this phenomenon are still unknown. NKG2D is an activating cell surface receptor expressed by natural killer (NK) cells and CD8+ T cells, and it has been reported that NKG2D engagement is extremely important for T cell activation. In the current study, NKG2D expression on CD8+ T cells and the frequency of CD4+ CD25+ regulatory T (Treg) cells were determined by multicolor flow cytometry to investigate one of the mechanisms responsible for immune evasion in esophageal cancer patients. NKG2D expression on CD8+ T lymphocytes in esophageal cancer patients was significantly lower than in those of normal controls. NKG2D expression in T3/T4 esophageal cancer was significantly lower than that in T1/T2 esophageal cancer. CD8+ T cells from patients with lymph node metastasis expressed significantly lower NKG2D than those without lymph node metastasis. Moreover, significantly lower NKG2D expression was observed in stage III/IV cancer in comparison with stage I/II. The frequency of CD4+CD25+ Treg cells in esophageal cancer patients was significantly higher than those in normal controls. NKG2D expression on CD8+ T cells was significantly inversely correlated with the frequency of CD4+CD25+ Treg cells in esophageal cancer patients. Our data indicates that decreased NKG2D expression on CD8+ T cells is correlated with disease severity. Decreased NKG2D expression and an increase in Treg cells may be one of the key mechanisms responsible for immune evasion in esophageal cancer.

Cacao Liquor Proanthocyanidins Inhibit Lung Injury Induced by Diesel Exhaust Particles

Epidemiological and experimental studies have suggested that diesel exhaust particles (DEPs), which generate reactive oxygen species, may be involved in the recent increase in the prevalence of lung diseases. Cacao liquor proanthocyanidins (CPs) are naturally occurring polyphenols with antioxidative activities. We carried out a study in mice to investigate the effects of dietary supplementation of CPs on lung injury induced by intratracheal administration of DEPs (500 μg/body). Dietary supplementation with 1.0% CPs inhibited DEP-induced lung injury, characterized by neutrophil sequestration and edema. Immunohistochemical analyses showed that CPs prevented enhanced expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 caused by DEPs in the lung injury. Numerous adducts of nitrotyrosine, N-(hexanonyl) lysine, 4-hydroxy-2-nonenal, and 8-OHdG were also observed immunohistochemically in the lungs of mice treated with DEPs. However, these indicators of oxidative stress were barely visible in mice pretreated with CP supplementation. In addition, the level of thiobarbituric acid reactive substances in the lung was decreased by CP supplementation in the presence of DEPs. These results suggest that CPs inhibit DEP-induced lung injury by reducing oxidative stress, in association with a reduction in the expression of adhesion molecules.

Overexpression of RegIV in peritoneal dissemination of gastric cancer and its potential as A novel marker for the detection of peritoneal micrometastasis

BACKGROUND

Regenerating gene type IV (RegIV) is a candidate marker for cancer and inflammatory bowel disease. In this study, its potential as a novel marker for the detection of gastric cancer peritoneal micrometastases was examined.

PATIENTS AND METHODS

RegIV mRNA levels in the peritoneal washes of 95 gastric cancer patients and 22 with benign disease were quantified by real-time RT-PCR. To examine whether expression of RegIV enhance tumorigenicity or not, thirty two mice were injected intraperitoneally or subcutaneously with RegIV transfectants of TMK-1 cells, parental TMK-1 cells, or neomycin control transfectants.

RESULTS

RegIV expression was markedly higher in patients with peritoneal metastases compared to those without. The level of RegIV mRNA in gastric cancer patients was related to the extent of wall penetration. A cut-off value for RegIV-positive expression was based on an analysis of negative control patients with benign disease, and gastric cancer patients above the cut-off value constituted the micrometastasis (MM+) group. Based on this criteria, 3 out of 43 T1 or T2 cases were MM+ (93% specificity). Among 15 patients with peritoneal dissemination (7 out of 15 cases were positive by cytology), 14 cases were positive for RegIV expression (93% sensitivity), while analysis of carcinoembryonic antigen (CEA) mRNA failed to detect micrometastases in 4 cases (73% sensitivity). Combined analysis of CEA and RegIV improved the accuracy of diagnosis to 100%. The prognosis of RegIV-positive cases was significantly worse than that of RegIV-negative cases. Multivariate analysis using the Cox proportional hazards model suggested that RegIV may be an independent prognostic factor. Stable expression of RegIV significantly enhanced peritoneal metastasis in an animal model of gastric cancer.

CONCLUSION

These findings suggest that RegIV mRNA expression has the potential to serve as a novel marker for detecting peritoneal dissemination in gastric cancer.

Salt effect on the heat-induced association behavior of gold nanoparticles coated with poly(N-isopropylacrylamide) prepared via reversible addition-fragmentation chain transfer (RAFT) radical polymerization

Poly(N-isopropylacrylamide) (PNIPAM) with a narrow molecular weight distribution was prepared by reversible addition-fragmentation chain transfer (RAFT) radical polymerization. A dithioester group at the chain end of PNIPAM thus prepared was cleaved by treating with 2-ethanolamine to provide thiol-terminated PNIPAM with which gold nanoparticles were coated via reactions of the terminal thiol with gold. The thermoresponsive nature of the maximum wavelength of the surface plasmon band and hydrodynamic radius (Rh) for the PNIPAM-coated gold nanoparticles were found to be sensitively affected by added salt. In pure water, Rh for the PNIPAM-coated gold nanoparticles at 40 degrees C (>lower critical solution temperature (LCST)) was smaller than that at 25 degrees C (<LCST) due to the shrinkage of the PNIPAM chains on the gold surface. The maximum wavelength of the plasmon band in pure water was almost independent of the temperature, the color of the solution remaining pink regardless of temperature. On the other hand, in the presence of 50 mM NaCl, the plasmon band at 40 degrees C was red shifted compared with that at 25 degrees C because of interparticle associations, the pink color at 25 degrees C changing to blue-purple at 40 degrees C. Furthermore, Rh for the PNIPAM-coated gold nanoparticles at 40 degrees C was significantly larger than that at 25 degrees C. Heat-induced association and dissociation for the PNIPAM-coated gold nanoparticles were completely reversible in 50 mM NaCl aqueous solutions, which is responsible for the reversible thermoresponsive color change.

Chondrosarcoma of the hyoid bone

Chondrosarcoma of the head and neck is relatively rare. We report the sixth case known to us in which the chondrosarcoma had originated in the hyoid bone. The patient, a 66-year-old man, underwent surgery. The resected tumour was a 5 cm encapsulated lesion composed of lobulated, firm, gray-white tissue. Histologically it showed mature chondrocytes without capsular invasion. There was high cellularity and a few binucleated chondrocytes. Although the tumour grade was prognostic significance, our literature review of the five other cases suggests that the location of the primary lesion and the adequacy of its resection to be more important. Our patient continues to do well 15 months post-operatively. However, long-term follow-up is essential as recurrences have been reported even after eight or 10 years.

An unusual dorsal fracture-dislocation of the proximal interphalangeal joint

A case of dorsal fracture-dislocation of the proximal interphalangeal joint in which the volar plate had been pulled from its distal attachment without bony or cartilaginous attachments and the lip of the volar plate had also been detached separately and was obstructing full flexion of the joint is presented. A tentative mechanism of causation of this unusual variant of a common injury is suggested.

Interleukin 10 and transforming growth factor beta contribute to the development of experimentally induced allergic conjunctivitis in mice during the effector phase

AIM

To investigate the involvement of interleukin (IL)10 and transforming growth factor (TGF) beta in the development of experimentally induced allergic conjunctivitis in mice.

METHODS

Balb/c mice were actively sensitised with ragweed in alum, and then challenged with ragweed in eye drops after 10 days. 24 h later, the conjunctivas, spleens and blood were collected for histological and cytokine expression analyses, proliferation and cytokine production assays and measurement of immunoglobulin (Ig) levels. Mice developing experimentally induced allergic conjunctivitis were injected intraperitoneally with 200 microg of anti-IL10 or anti-TGF beta antibodies at 0, 2, 4, 6 and 8 days (induction phase treatment) or 500 microg of antibodies 2 h before ragweed challenge (effector phase treatment). Normal rat IgG was used for control injections.

RESULTS

Treatment with either anti-IL10 or anti-TGF beta antibodies during the induction phase did not affect eosinophil infiltration into the conjunctiva. By contrast, treatment with either antibody during the effector phase suppressed infiltration. During the effector phase, treatment with anti-TGF beta antibody, but not the anti-IL10 antibody, markedly up regulated proliferation and Th2 cytokine production by splenocytes. IL1alpha levels in the conjunctiva were reduced after treatment with either antibody; in addition, eotaxin and tumour necrosis factor alpha levels were reduced after treatment with antibody to TGF beta.

CONCLUSIONS

IL10 and TGF beta do not have immunosuppressive roles in the development of experimentally induced allergic conjunctivitis. Rather, they augment the infiltration of eosinophils into the conjunctiva during the effector phase of experimentally induced allergic conjunctivitis.

Hypoxia-induced hyaluronan synthesis by articular chondrocytes: the role of nitric oxide

OBJECTIVE

Articular cartilage is an avascular tissue in which chondrocytes are exposed to hypoxic conditions. We previously demonstrated that reactive oxygen species (ROS) induced apoptosis of chondrocytes. We also demonstrated that nitric oxide (NO) was induced when chondrocytes were exposed to hypoxia and that NO inhibited the ROS-induced apoptosis. Hyaluronan (HA) is a high molecular weight glycosaminoglycan whose antioxidative effects have been reported. The purpose of the present study was to determine whether HA synthesis was induced in chondrocytes exposed to hypoxia, and, if so, whether the hypoxia-induced HA synthesis is regulated by NO.

METHODS

Bovine articular chondrocytes were used in this study. Levels of HA were determined by the sandwich enzyme-binding assay. Expression of HA synthase (HAS) was determined with reverse transcription-polymerase chain reaction. The production of NO was examined using the Griess reaction. We also determined inducible nitric oxide synthase (iNOS) enzyme synthesis using the histochemistry and Western blot analysis.

RESULTS

Chondrocytes cultured under hypoxic conditions exhibited enhanced HA synthesis. When the NO inhibitors, L-NMMA and L-NAME, were added, the hypoxia-enhanced HA levels in the culture medium were significantly inhibited.

CONCLUSIONS

Endogenous NO synthesis plays an important role in hypoxia-enhanced HA synthesis.

Genetic diversity of Legionella pneumophila inferred from rpoB and dotA sequences

This study characterised the population structure of Legionella pneumophila by comparing the rpoB (300-bp) and dotA (360-bp) sequences of 267 isolates (18 reference strains, 149 Korean isolates and 100 Japanese isolates). In addition to the six clonal subgroups established previously, four subgroups, P-V to P-VIII, were identified. Subgroupings based on rpoB and dotA sequences were found to correlate with the source of the isolates, and this data may be useful for future epidemiological studies. Fourteen (five Korean and nine Japanese) isolates showed incongruent subgroupings in the rpoB and dotA trees, suggesting that genetic exchange among subgroups, and even among subspecies, may occur frequently in nature.

Landiolol, an ultra-short-acting beta 1-adrenoceptor antagonist, does not alter the electroencephalographic effect of isoflurane in swine model

BACKGROUND

beta-Adrenergic blocking agents may interact with anaesthetics, and several studies suggest that beta-blockers attenuate electroencephalographic responses during general anaesthesia. We have investigated the influence of landiolol, an ultra-short-acting beta 1-adrenoceptor antagonist, on the electroencephalographic effect of isoflurane in pigs.

METHODS

Ten swine were anaesthetized through inhalation of 2% isoflurane. The inhalational concentration was then decreased to 0.5% and maintained for 25 min, before being returned to 2% and maintained for a further 25 min (control period). After control measurements, infusion of landiolol (at 0.125 mg kg(-1) min(-1) for 1 min, and then at 0.04 mg kg(-1) min(-1)) was started. After a 20 min stabilization period, the inhalational concentration was varied as in the control period (40 gamma landiolol). Finally, infusion of landiolol was increased from 0.04 to 0.2 mg kg(-1) min(-1), and after a 20 min stabilization period, the inhalational concentration was again varied as in the control period (200 gamma landiolol). End-tidal isoflurane concentrations and spectral edge frequencies were recorded throughout the study. Analysis of the pharmacodynamics was performed using a sigmoidal inhibitory maximal effect model for spectral edge frequency vs effect-site concentration.

RESULTS

There were no significant differences in the effect of isoflurane among the conditions used. Landiolol did not shift the concentration-effect relationship [the effect-site concentration that produced 50% of the maximal effect was 1.35 (0.17)% under control conditions, 1.30 (0.12)% at 40 gamma landiolol, and 1.38 (0.30)% at 200 gamma landiolol].

CONCLUSION

Landiolol does not alter the electroencephalographic effect of isoflurane.

Ischemia-induced disturbance of neuronal network function in the rat spinal cord analyzed by voltage-imaging

Using a voltage-imaging technique, we analyzed the acute effect of ischemia, hypoxia and hypoglycemia on the neuronal network function of the rat spinal cord. Ischemic, hypoxic, or hypoglycemic stress was loaded to spinal cord slices with an oxygen- and glucose-free, oxygen-free, or glucose-free mock cerebrospinal fluid, respectively. Depolarizing signals in the dorsal horn, induced by dorsal root stimulation, consisted of fast (pre-synaptic) and slow (post-synaptic) components. The slow component was attenuated much more than the fast component under an ischemic condition (P<0.0002). Post-synaptic neuronal activities in lamina III-IV were suppressed earlier than those in lamina I-II. The nerve fiber was relatively resistant to ischemia. As long as the fast component was preserved in the dorsal horn, the suppression of the fast and slow components was reversible. There was a significant difference (P<0.05) in the recovered slow component sizes between the group in which the fast component was suppressed by more than 20% by ischemia and the group in which the suppression was less than 20%. Further prolonged stress irreversibly eliminated most of the slow component, and attenuated the fast component (to 59+/-8%) accompanied by cellular damage in histology. Suppression of neural activity by hypoxic or hypoglycemic stress was less prominent than that by ischemia. Prolonged ischemic stress suddenly and irreversibly eliminated depolarizing signals in the ventral horn accompanied by morphological damage of motoneurons. Immunohistochemical staining was negative for apoptosis. We have, for the first time, analyzed the processes of spinal cord disturbance induced by ischemia, hypoxia and hypoglycemia at the neuronal network level by directly observing the regional neuronal network activities within the spinal cord. We conclude that synaptic transmission in the dorsal horn, especially in deep regions, is vulnerable and first affected by these stresses. Severe ischemic stress induces irreversible dysfunction of neurons accompanied by eventual cell death in both dorsal and ventral horns.

Experimental study on pathogenesis and histomorphology of early carcinoma of the extrahepatic bile duct in the Syrian hamster

To elucidate the pathogenesis of carcinomas in the extrahepatic bile duct, we investigated the histomorphological characteristics of adenomas and early carcinomas induced in the extrahepatic bile duct of hamsters. Syrian hamsters underwent a cholecystoduodenostomy along with a dissection of the common duct, while also being administered N-nitrosobis(2-oxopropyl)amine (BOP). The tumors that arose from the extrahepatic bile duct included 10 adenomas and 55 early carcinomas in 56 of the 156 hamsters sacrificed. All the adenomas were found to be polypoid in shape. The early carcinomas, which were restricted within the mucosal layer of the bile duct, showed the following three different growth patterns: (1) protruding type in 41 (75%), consisting of 27 polypoid and 14 papillary tumors; (2) superficial spreading type in 9 (16%); and (3) periductal glandular type in 5 (9%). There were no depressed tumors observed. Carcinomas existing either alone or associated with adenomas were evident in 12 (22%) tumors, and 11 of these were polypoid. Atypical papillary hyperplasia within the tumor mass was noted in 22 early carcinomas (40%) and was particularly prominent in papillary type tumors. These results support the concept of an adenoma-carcinoma sequence in the majority of polypoid tumors of the extrahepatic bile duct. Atypical papillary hyperplasia might also be premalignant, and these precursor lesions should reflect the growth patterns of tumors, at least in the early stage of tumorigenesis.

A case of bullous pemphigoid associated with autoantibodies targeting antigenic sites other than the NC16a domain of BP180

Bullous pemphigoid (BP) is associated with autoantibodies to the 180-kDa BP antigen (BP180), and the antigenic site exists on noncollagenous 16a (NC16a) domain of BP180. We now report a male BP patient whose IgG autoantibodies did not react against the NC16a domain of BP180 by either immunoblotting or ELISA, whereas they did react with BP180 extracted from normal human keratinocytes. Anti-BP180 cicatricial pemphigoid was ruled out due to the lack of conjunctival mucosal involvement and the absence of scarring in the oral cavity. Our findings indicate that there is an antigenic reactive region other than NC16a on the extracellular domain of BP180. There have been few reports describing detailed clinical features of BP caused by autoantibodies targeting antigenic sites other than the NC16a domain. We conclude that it is difficult to differentiate their clinical features from those associated with autoantibodies targeting the NC16a domain of BP180.

Genetic characterization of parthenogenic Fasciola sp. in Japan on the basis of the sequences of ribosomal and mitochondrial DNA

Accurate identification of aspermic Fasciola forms in Japan remains difficult because of their morphological variations. In order to characterize the forms genetically, nucleotide sequences of ribosomal internal transcribed spacer (ITS1 and ITS2) and mitochondrial cytochrome c oxidase I (COI) and NADH dehydrogenase I (NDI) genes in 34 liver flukes from 16 prefectures in Japan were analysed. Two major forms represented by Fsp 1 and Fsp 2 had sequences identical to or closely resembling those of F. hepatica and F. gigantica, respectively, in all the 4 DNA markers and were mainly distributed in northern and eastern-western parts of Japan, respectively. Fsp 1 and Fsp 2 would have been introduced into Japan with infected cattle of 2 distinct lineages via the Korean Peninsula and spread through limited parts of Japan (northern and eastern-western parts) together with the movement of each cattle lineage. The Japanese form (Fsp 1/2), which showed heterozygosity in ribosomal DNA and Fsp 2 haplotype in mitochondrial DNA, may have originated in interspecific cross hybridization between paternal F. hepatica and maternal F. gigantica.

Nociceptin system does not affect MAC of volatile anaesthetics

BACKGROUND

Nociceptin is the endogenous agonist of the opioid receptor-like (ORL) 1 receptor (NOP), and both nociceptin and NOP are widely expressed in the brain and spinal cord, which are target organs of general anaesthetics. As nociceptin has been reported to be involved in modulating pain mechanisms and stress responses, it is possible that the activity of the nociceptin system affects the anaesthetic potency of general anaesthetics. To address this possibility, we investigated the minimum alveolar concentrations (MACs) of various volatile anaesthetics in nociceptin receptor knockout mice (NOP-/-) and wild-type mice (NOP+/+).

METHODS

We used male NOP-/- mice and NOP+/+ mice. MACs for halothane, isoflurane and sevoflurane were determined by the tail-clamp method.

RESULTS

MACs for halothane, isoflurane and sevoflurane in NOP-/- mice were 1.60 (SD 0.06), 1.68 (0.08) and 3.36 (0.07)%, respectively. In NOP+/+ mice, MACs for halothane, isoflurane and sevoflurane were 1.59 (SD 0.07), 1.72 (0.07) and 3.38 (0.09)%, respectively.

CONCLUSION

MACs in NOP-/- mice did not significantly differ from those in NOP+/+ mice for halothane, isoflurane and sevoflurane. This result suggests that the nociceptin system does not affect the anaesthetic potency of volatile anaesthetics.

Cyclic tensile stretch stimulates the release of reactive oxygen species from osteoblast-like cells

It is known that the excessive generation of reactive oxygen species (ROS) is a significant factor in tissue injury observed in many disease states. To determine whether extreme levels of mechanical stress applied to osteoblasts enhances ROS synthesis, we loaded cyclic tensile stretch on osteoblast-like HT-3 cells. Cyclic tensile stretch loaded on these cells clearly enhanced ROS synthesis in a time- and magnitude-dependent fashion. Cyclic tensile stretch also enhanced superoxide dismutase (SOD) activity. The disruption of microfilaments with cytochalasin D abolished the stress-induced ROS synthesis. Rotenone, an inhibitor of the mitochondrial electron transport chain, enhanced stress-induced ROS synthesis. These data suggest that actin filament and mitochondria are involved in this action.

Effect of hypercapnia on arterial hypotension after induction of anaesthesia

We evaluated the effectiveness of intentional hypercapnia against hypotension after induction of anaesthesia with thiopental and isoflurane (TI) or propofol (P). For each group, 24 patients were anaesthetized with thiopental 4 mg kg(-1) (TI) or propofol 2 mg kg(-1) (P) for tracheal intubation and then lightly anaesthetized with isoflurane at 0.6% end-expiratory concentration (TI) or by 6 mg kg(-1) h(-1) infusion of propofol (P). In both anaesthesia groups, patients were randomly assigned to either normocapnia (end-tidal CO(2) = 35 mmHg) or hypercapnia (end-tidal CO(2) = 45 mmHg), which were achieved through adjusting the tidal volume. Systolic arterial pressure (SAP) 15 min after intubation was compared with the preanaesthetic baseline value. Under normocapnia, both TI and P induced a comparable, statistically significant suppression of SAP by approximately 20 mmHg from baseline. Hypercapnia prevented the decrease in SAP in TI but not in P. No patient in the TI-hypercapnia group experienced SAP below 100 mmHg, unlike those in the other groups. In conclusion, mild hypercapnia was effective in the prevention of hypotension in patients receiving thiopental followed by 0.6% end-expiratory isoflurane, but not in patients receiving 6 mg kg(-1) h(-1) propofol.