Improving the capacity of researchers and bereaved parents to co-design and translate stillbirth research together

BACKGROUND

Working with bereaved parents in co-designed stillbirth research, policy and practice is essential to improving care and outcomes.

PROBLEM

Effective parent engagement is often lacking. This may be due to bereaved parents not feeling adequately and appropriately supported to be involved.

AIM

To consult bereaved parents with the aim to understand their experiences, attitudes, and needs around involvement in stillbirth research and gain feedback about the usefulness and appropriateness of a proposed co-designed guide to support their involvement, including content and design aspects of this resource.

METHODS

An online co-designed survey was disseminated via Australian parent support organisations social media in August 2022.

FINDINGS

All 90 respondents were bereaved parents, 94% (n = 85) were female. Two-thirds (67%, n = 60) had never participated in stillbirth research, 80% (n = 72) agreed involvement of bereaved parents in research was important or extremely important and 81% (n = 73) were interested in future research involvement. Common motivations for involvement were wanting to leave a legacy for their baby and knowing research outcomes. Common barriers included not having been asked to participate or not knowing how. Most (89%, n = 80) agreed the proposed guide would be useful. Highly valued topics were the importance of bereaved parents' voices in stillbirth research and how they can make a difference.

CONCLUSION

The majority of bereaved parents we surveyed want to be involved in stillbirth research and would value a resource to support this. The proposed concept and content for a co-designed guide to aid engagement was well supported.

BNP level predicts bleeding event in patients with heart failure after percutaneous coronary intervention

OBJECTIVE

This study aimed to investigate the association between heart failure (HF) severity measured based on brain natriuretic peptide (BNP) levels and future bleeding events after percutaneous coronary intervention (PCI).

BACKGROUND

The Academic Research Consortium for High Bleeding Risk presents a bleeding risk assessment for antithrombotic therapy in patients after PCI. HF is a risk factor for bleeding in Japanese patients.

METHODS

Using an electronic medical record-based database with seven tertiary hospitals in Japan, this retrospective study included 7160 patients who underwent PCI between April 2014 and March 2020 and who completed a 3-year follow-up and were divided into three groups: no HF, HF with high BNP level and HF with low BNP level. The primary outcome was bleeding events according to the Global Use of Streptokinase and t-PA for Occluded Coronary Arteries classification of moderate and severe bleeding. The secondary outcome was major adverse cardiovascular events (MACE). Furthermore, thrombogenicity was measured using the Total Thrombus-Formation Analysis System (T-TAS) in 536 consecutive patients undergoing PCI between August 2013 and March 2017 at Kumamoto University Hospital.

RESULTS

Multivariate Cox regression showed that HF with high BNP level was significantly associated with bleeding events, MACE and all-cause death. In the T-TAS measurement, the thrombogenicity was lower in patients with HF with high BNP levels than in those without HF and with HF with low BNP levels.

CONCLUSIONS

HF with high BNP level is associated with future bleeding events, suggesting that bleeding risk might differ depending on HF severity.

Impact of heart failure severity and major bleeding events after percutaneous coronary intervention on subsequent major adverse cardiac events

Background

Heart failure (HF) is associated with a high bleeding risk after percutaneous coronary intervention (PCI). Additionally, major bleeding events increase the risk of subsequent major adverse cardiac events (MACE). However, whether brain natriuretic peptide (BNP) levels and major bleeding events following PCI are associated with MACE and all-cause death remains unknown. This study aimed to investigate the impact of HF severity or bleeding on subsequent MACE and all-cause death.

Methods

The Clinical Deep Data Accumulation System (CLIDAS), a multicenter database involving seven hospitals in Japan, was developed to collect data from electronic medical records. This retrospective analysis included 7160 patients who underwent PCI between April 2014 and March 2020 and completed a three-year follow-up. Patients were divided according to the presence of HF with high BNP (HFhBNP) (>100 pg/ml) and major bleeding events within 30 days post-PCI (30-day bleeding): HFhBNP with bleeding (n = 14), HFhBNP without bleeding (n = 370), non-HFhBNP with bleeding (n = 74), and non-HFhBNP without bleeding (n = 6702).

Results

In patients without 30-day bleeding, HFhBNP was a risk factor for MACE (hazard ratio, 2.19; 95% confidence interval, 1.56-3.07) and all-cause death (hazard ratio, 1.60; 95% confidence interval, 1.60-2.23). Among HFhBNP patients, MACE incidence was higher in patients with 30-day bleeding than in those without bleeding, but the difference was not significant (p = 0.075). The incidence of all-cause death was higher in patients with bleeding (p = 0.001).

Conclusions

HF with high BNP and bleeding events in the early stage after PCI might be associated with subsequent MACE and all-cause death.

Neutron resonance absorption imaging of simulated high-level radioactive waste in borosilicate glass

We performed a preliminary study of neutron resonance absorption imaging to investigate the spatial distribution of constituent elements in borosilicate glasses containing simulated high-level radioactive waste, in which elemental inhomogeneities affect the physical and chemical stabilities of the glass. Dips generated by the resonance absorptions of Rh, Pd, Na, Gd, Cs, and Sm were observed in the neutron transmission spectra of the glass samples. The spatial distributions of these elements were obtained from the neutron transmission images at the resonance energies. The distributions of Rh and Pd visualized the sedimentation of these platinum group elements. In contrast, the lanthanides (Gd and Sm) and Cs were uniformly dispersed. These results show that neutron resonance absorption imaging is a promising tool for characterizing borosilicate glasses and investigating the vitrification mechanism of high-level radioactive waste.

Sex Differences in Long-Term Outcomes in Patients With Chronic Coronary Syndrome After Percutaneous Coronary Intervention - Insights From a Japanese Real-World Database Using a Storage System

BACKGROUND

Several studies have reported some sex differences in patients with coronary artery diseases. However, the results regarding long-term outcomes in patients with chronic coronary syndrome (CCS) are inconsistent. Therefore, the present study investigated sex differences in long-term outcomes in patients with CCS after percutaneous coronary intervention (PCI).Methods and Results: This was a retrospective, multicenter cohort study. We enrolled patients with CCS who underwent PCI between April 2013 and March 2019 using the Clinical Deep Data Accumulation System (CLIDAS) database. The primary outcome was major adverse cardiovascular events (MACE), defined as a composite of cardiovascular death, non-fatal myocardial infarction, or hospitalization for heart failure. In all, 5,555 patients with CCS after PCI were included in the analysis (4,354 (78.4%) men, 1,201 (21.6%) women). The median follow-up duration was 917 days (interquartile range 312-1,508 days). The incidence of MACE was not significantly different between the 2 groups (hazard ratio [HR] 1.20; 95% confidential interval [CI] 0.97-1.47; log-rank P=0.087). After performing multivariable Cox regression analyses on 4 different models, there were still no differences in the incidence of MACE between women and men.

CONCLUSIONS

There were no significant sex differences in MACE in patients with CCS who underwent PCI and underwent multidisciplinary treatments.

Relationships Among Heart Rate, β-Blocker Dosage, and Prognosis in Patients With Coronary Artery Disease in a Real-World Database Using a Multimodal Data Acquisition System

BACKGROUND

The optimal heart rate (HR) and optimal dose of β-blockers (BBs) in patients with coronary artery disease (CAD) have been unclear. We sought to clarify the relationships among HR, BB dose, and prognosis in patients with CAD using a multimodal data acquisition system.Methods and Results: We evaluated the data for 8,744 CAD patients who underwent cardiac catheterization from 6 university hospitals and the National Cerebral and Cardiovascular Center and who were registered using the Clinical Deep Data Accumulation System. Patients were divided into quartile groups based on their HR at discharge: Q1 (HR <60 beats/min), Q2 (HR 60-66 beats/min), Q3 (HR 67-74 beats/min), and Q4 (HR ≥75 beats/min). Among patients with acute coronary syndrome (ACS) and patients with chronic coronary syndrome (CCS), those in Q4 (HR ≥75 beats/min) had a significantly greater incidence of major adverse cardiac and cerebral events (MACCE) compared with those in Q1 (ACS patients: hazard ratio 1.65, P=0.001; CCS patients: hazard ratio 1.45, P=0.019). Regarding the use of BBs (n=4,964), low-dose administration was significantly associated with MACCE in the ACS group (hazard ratio 1.41, P=0.012), but not in patients with CCS after adjustment for covariates.

CONCLUSIONS

HR ≥75 beats/min was associated with worse outcomes in patients with CCS or ACS.

Hyperuricemia predicts increased cardiovascular events in patients with chronic coronary syndrome after percutaneous coronary intervention: A nationwide cohort study from Japan

Background

The causal relationship between hyperuricemia and cardiovascular diseases is still unknown. We hypothesized that hyperuricemic patients after percutaneous coronary intervention (PCI) had a higher risk of major adverse cardiovascular events (MACE).

Methods

This was a large-scale multicenter cohort study. We enrolled patients with chronic coronary syndrome (CCS) after PCI between April 2013 and March 2019 using the database from the Clinical Deep Data Accumulation System (CLIDAS), and compared the incidence of MACE, defined as a composite of cardiovascular death, myocardial infarction, and hospitalization for heart failure, between hyperuricemia and non-hyperuricemia groups.

Results

In total, 9,936 patients underwent PCI during the study period. Of these, 5,138 patients with CCS after PCI were divided into two group (1,724 and 3,414 in the hyperuricemia and non-hyperuricemia groups, respectively). The hyperuricemia group had a higher prevalence of hypertension, atrial fibrillation, history of previous hospitalization for heart failure, and baseline creatinine, and a lower prevalence of diabetes than the non-hyperuricemia group, but the proportion of men and age were similar between the two groups. The incidence of MACE in the hyperuricemia group was significantly higher than that in the non-hyperuricemia group (13.1 vs. 6.4%, log-rank P < 0.001). Multivariable Cox regression analyses revealed that hyperuricemia was significantly associated with increased MACE [hazard ratio (HR), 1.52; 95% confidential interval (CI), 1.23-1.86] after multiple adjustments for age, sex, body mass index, estimated glomerular filtration rate, left main disease or three-vessel disease, hypertension, diabetes mellitus, dyslipidemia, history of myocardial infarction, and history of hospitalization for heart failure. Moreover, hyperuricemia was independently associated with increased hospitalization for heart failure (HR, 2.19; 95% CI, 1.69-2.83), but not cardiovascular death or myocardial infarction after multiple adjustments. Sensitive analyses by sex and diuretic use, B-type natriuretic peptide level, and left ventricular ejection fraction showed similar results.

Conclusion

CLIDAS revealed that hyperuricemia was associated with increased MACE in patients with CCS after PCI. Further clinical trials are needed whether treating hyperuricemia could reduce cardiovascular events or not.

Small-angle neutron scattering by spatially inhomogeneous ferromagnets with a nonzero average uniaxial anisotropy

Macroscopic spin-misalignment small-angle neutron scattering cross sections and response functions are computed analytically for a material with global uniaxial magnetic anisotropy (texture). The resulting expressions are tested against previously published experimental data.

Micromagnetic small-angle neutron scattering theory is well established for analyzing spin-misalignment scattering data of bulk ferromagnets. Here, this theory is extended to allow for a global uniaxial magnetic anisotropy (texture) of the material, in addition to the already included random zero-average local anisotropy. Macroscopic cross sections and spin-misalignment response functions are computed analytically for several practically relevant mutual anisotropy and external magnetic field orientations in both parallel and perpendicular scattering geometries for field magnitudes both above and below the rotational saturation. Some of these expressions are tested on published experimental data of magnetic-field-annealed Vitroperm and plastically deformed Ni, allowing determination of the corresponding global uniaxial anisotropy quality factors.

The relationships among the pulse rate, use of beta-blockers, and prognosis in patients with ischemic heart disease in a real-world database using a storage system

Background

The use of β-blockers has the effect of improving the prognosis of patients with ischemic heart disease (IHD). One of the underlying mechanisms is a decrease in the cardiac load due to a reduction in the heart rate.

Purpose

To clarify the relationships among the pulse rate, the use of β-blockers, and the prognosis in patients with IHD in a multicenter study using a storage system.

Methods

The Clinical Deep Data Accumulation System (CLIDAS) collects (1) basic patient information, prescriptions, and laboratory data from electronic medical records from the Standardized Structured Medical Information eXchange (SS-MIX2) standard storage, and (2) the results of physiological tests, cardiac catheterization, and cardiac catheter intervention reports from the SS-MIX2 extended storage. 8540 cases who underwent cardiac catheterization from 6 university hospitals and the national cardiovascular center in Japan were registered (male: 77%, average age: 70.2 years). We evaluated these patients' pulse rate at admission and at the discharge of cardiac catheterization in 6,598 patients. We divided the pulse rates at discharge into quartiles (Q1: &lt;60, Q2: 60–66, Q3: 67–75, Q4: ≥76 bpm), and we analyzed the relationship between the pulse rate and the prognosis by dividing the patients into the stable angina group (n=2,631) and the acute coronary syndrome (ACS) group (n=2,394). Regarding the use of β-blockers, we compared the pulse rates of the patients taking carvedilol (n=1,728) and those taking bisoprolol (n=2,761) at admission and discharge. Major adverse cardiovascular events (MACE) were defined as cardiovascular death, non-fatal myocardial infarction, unstable angina, heart failure, stroke, and other hospitalized cardiovascular events.

Results

A total of 600 MACEs occurred during an average observation period of 890 days. The incidence of cardiovascular events was significantly higher in the Q4 patients in the stable angina group (hazard ratio 1.79, 95% confidence interval 1.32–2.41, but there was no significant difference among the four pulse rate subgroups in the ACS group. The bisoprolol-treated patients had lower pulse rates at discharge (67.4±12.2 vs. 68.8±11.8 bpm, p&lt;0.001) and a lower percentage of patients in the Q4 group (21.2 vs. 24.9%, p=0.005) compared to the carvedilol-treated patients. The pulse rate at admission was similar in the bisoprolol- and carvedilol-treated patients (74.3±19.3 vs. 73.2±29.5 bpm, p=0.328).

Conclusion

In a real-world database using a storage system, a pulse rate of ≤75 bpm was associated with a good prognosis in patients with ACS. Compared to carvedilol, bisoprolol was associated with a decreased pulse rate at discharge.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Kowa Company, Ltd.

In-hospital outcomes and usage of embolic protection devices in percutaneous coronary intervention for coronary artery bypass grafts: Insights from a Japanese nationwide registry

OBJECTIVES

We evaluated the in-hospital outcomes of percutaneous coronary intervention (PCI) for bypass graft vessels (GV-PCI) compared with those of PCI for native vessels (NV-PCI) using data from the Japanese nationwide coronary intervention registry.

METHODS

We included PCI patients (N = 748,229) registered between January 2016 and December 2018 from 1,123 centers. We divided patients into three groups: GV-PCI (n = 2,745); NV-PCI with a prior coronary artery bypass graft (pCABG) (n = 23,932); and NV-PCI without pCABG (n = 721,552).

RESULTS

GV-PCI implementation was low, and most cases of PCI in pCABG patients were performed in native vessels (89.7%) in contemporary Japanese practice. The risk profile of patients with pCABG was higher than that of those without pCABG. Consequently, GV-PCI patients had a significantly higher in-hospital mortality than NV-PCI patients without pCABG after adjusting for covariates (odds ratio [OR] 2.36, 95% confidence interval [CI] 1.66-3.36, p < .001). Of note, embolic protection devices (EPDs) were used in 18% (n = 383) of PCIs for saphenous vein grafts (SVG-PCI) with a significant variation in its use among institutions (number of PCI: hospitals that had never used an EPD vs. EPD used one or more times = 240 vs. 345, p < .001). The EPDs used in the SVG-PCI group had a significantly lower prevalence of the slow-flow phenomenon after adjusting for covariates (OR 0.45, 95% CI 0.21-0.91, p = .04).

CONCLUSION

GV-PCI is associated with an increased risk of in-hospital mortality. EDP use in SVG-PCI was associated with a low rate of the slow-flow phenomenon. The usage of EPDs during SVG-PCI is low, with a significant variation among institutions.

The long-term prognostic factors in hemodialysis patients with acute coronary syndrome: perspectives from sarcopenia and malnutrition

Hemodialysis (HD) patients tend to have sarcopenia and malnutrition, and both conditions are related to poor prognosis in the cardiovascular disease that often accompanies HD. However, the impact of sarcopenia or malnutrition on the long-term prognosis of HD patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) remains unclear. We analyzed 1,605 consecutive patients with ACS who had undergone PCI at a single center between January 2009 and December 2014. We evaluated all-cause mortality and prognosis-associated factors, including sarcopenia/malnutrition-related factors such as the Geriatric Nutritional Risk Index (GNRI), and Skeletal Muscle Mass Index (SMI). After exclusions, 1461 patients were enrolled, and 58 (4.0%) were on HD. The HD group had lower levels of SMI and GNRI than non-HD group, and had worse in-hospital prognosis. Moreover, HD group had a significant higher mortality in the long-term follow-up [median follow-up period: 1219 days; Hazard Ratio (HR) = 4.09, p < 0.001]. After adjusting the covariates, SMI and GNRI were the factors associated with all-cause mortality in all patients [SMI: adjusted HR (aHR) = 2.39, p = 0.036; GNRI: aHR = 2.21, p = 0.006]; however, these findings were not observed among HD patients with ACS, and only diabetes was significantly associated with all-cause mortality (diabetes: aHR = 3.50, p = 0.031). HD patients with ACS had a significantly higher rate of in-hospital and long-term mortality than non-HD patients. Although sarcopenia and malnutrition were related to mortality and were more common in HD patients, sarcopenia and malnutrition had a lower impact than diabetes on the long-term prognosis of HD patients with ACS.

Resurrecting the ancient glow of the fireflies

The color of firefly bioluminescence is determined by the structure of luciferase. Firefly luciferase genes have been isolated from more than 30 species, producing light ranging in color from green to orange-yellow. Here, we reconstructed seven ancestral firefly luciferase genes, characterized the enzymatic properties of the recombinant proteins, and determined the crystal structures of the gene from ancestral Lampyridae. Results showed that the synthetic luciferase for the last common firefly ancestor exhibited green light caused by a spatial constraint on the luciferin molecule in enzyme, while fatty acyl-CoA synthetic activity, an original function of firefly luciferase, was diminished in exchange. All known firefly species are bioluminescent in the larvae, with a common ancestor arising approximately 100 million years ago. Combined, our findings propose that, within the mid-Cretaceous forest, the common ancestor of fireflies evolved green light luciferase via trade-off of the original function, which was likely aposematic warning display against nocturnal predation.

The Early Diagnosis of Endophthalmitis Due to Group B Streptococcus Infective Endocarditis and Its Clinical Course: A Case Report and Literature Review

A 68-year-old Japanese man was admitted to our hospital with right eye pain, a sudden worsening of his eyesight, and a fever. He was diagnosed with endogenous bacterial endophthalmitis due to infectious endocarditis (IE) of Group B Streptococcus (GBS) on the day of admission. He recovered systemically, but his right eye became phthisical only with the administration of antibiotics. We conducted a review of the reported cases of IE caused by GBS complicated with endogenous bacterial endophthalmitis. IE should be considered when an undetermined etiology of endogenous endophthalmitis is encountered. The prompt diagnosis and treatment of IE will improve patients' outcomes.

Evaluation of stent length on the outcome of ST-segment elevation myocardial infarction receiving primary percutaneous coronary intervention

BACKGROUND

A longer stent length is known to be a predictor of adverse events after a percutaneous coronary intervention (PCI). However, the evaluation of the stent length on the outcome of ST-segment elevation myocardial infarction (STEMI) patients is not enough.

PATIENTS AND METHODS

A total of 686 STEMI patients who underwent primary PCI were divided into four groups according to the total stent length as follows: short (<18 mm, n=183), lower-medium (18-23 mm, n=256), upper-medium (24-31 mm, n=155), and long (≥32 mm, n=92). We compared the all-cause mortality, major adverse cardiovascular events (MACEs; composite of cardiovascular death, myocardial infarction, and stroke after discharge), target lesion revascularization, and target vessel revascularization with a median follow-up of 1213 days among these four groups.

RESULTS

There were no significant differences in MACEs (10.4% in the short, 7.0% in the lower-medium, 6.5% in the upper-medium, 7.6% in the long, P=0.633) among the different stent length groups. The all-cause mortality, target lesion revascularization, and target vessel revascularization also did not differ among the four groups. In the drug-eluting stent (n=237) and bare-metal stent subgroups (n=449), all outcomes were comparable among the groups. However, in the diabetes subgroup (n=265), the rate of MACEs was higher in the long group than in the other groups, although the difference was not significant (6.6% in the short, 9.6% in the lower-medium, 3.4% in upper-medium, 16.7% in long group, P=0.095).

CONCLUSION

A long stent length was not associated with adverse clinical outcomes in STEMI patients who underwent primary PCI.

Outcome of staged percutaneous coronary intervention within two weeks from admission in patients with ST-segment elevation myocardial infarction with multivessel disease

BACKGROUND

The optimum timing of revascularization strategy for stenoses in nonculprit vessels in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease (MVD) remains unclear. At present, there is no evidence investigating the outcome of staged percutaneous coronary intervention (PCI) within two weeks from admission among STEMI patients with MVD.

METHODS

A total of 210 STEMI patients with MVD who underwent primary PCI were analyzed. We compared the all-cause mortality and major adverse cardiovascular events (MACE) (cardiovascular death, myocardial infarction, heart failure, unstable angina, and stroke) with median follow-up of 1200 days among the patients who underwent staged PCI within two weeks from admission (staged PCI ≤2 W) (n = 75), staged PCI after two weeks from admission (staged PCI >2 W) (n = 37) and culprit-only PCI (n = 98) in patients with STEMI and MVD.

RESULTS

The staged PCI ≤2 W showed lower all-cause mortality than culprit-only PCI (4.0 vs 29.6%, log-rank P = 0.001), and lower incidence of MACE than the staged PCI >2 W group (1.3 vs 18.9%, log-rank P = 0.001) and culprit-only PCI group (1.3 vs 22.5%, log-rank P = 0.001). In the multivariable Cox regression analysis, the staged PCI ≤2 W was a predictor of lower all-cause mortality (hazard ratio [HR], 0.176; 95% confidence interval [CI], 0.049-0.630; P = 0.008) and lower incidence of MACE (HR, 0.068; 95% CI, 0.009-0.533; P = 0.011), but staged PCI >2 W was not.

CONCLUSION

In conclusion, staged PCI within two weeks after admission showed more favorable outcomes compared with staged PCI after two weeks from admission or culprit-only PCI in STEMI patients with MVD.

Increased Resting Heart Rate on Electrocardiogram Relative to In-office Pulse Rate Indicates Cardiac Overload: The J-HOP Study

BACKGROUND

Heart rate (HR) assessed by electrocardiogram (ECG-HR) and pulse rate (PR) measured in a physician's office (office-PR) are taken with subjects in different body positions-i.e., supine vs. sitting. Although analysis of HR differences according to body position could provide new practical insights, there have been few studies on the subject. We herein investigated whether the difference between office-PR and ECG-HR (delta HR) was associated with brain natriuretic peptide (BNP) levels and left ventricular mass (LVM).

METHODS

Among the 4,310 patients with 1 or more cardiovascular risk factors recruited for the Japan Morning Surge-Home Blood Pressure study, we excluded those with atrial fibrillation or a prescribed β-blocker. We analyzed the 2,972 patients who had ECG-HR, office-PR, and BNP data and 1,061 patients with echocardiography data.

RESULTS

In the complete patient series, office-PR was significantly higher than ECG-HR (72.1 ± 10.3 vs. 66.6 ± 11.9 bpm, P < 0.001). When we divided patients into quintiles based on the delta HR, the BNP level and LVM index (LVMI) decreased across categories after adjustment for traditional cardiovascular risk factors (each P ≤ 0.001). In a multiple linear regression analysis, the delta HR was independently and significantly associated with both the log-transformed BNP level (β = -0.179, P < 0.001) and LVMI (β = -0.113, P = 0.001) adjusted for covariates.

CONCLUSION

A decreased delta HR was positively associated with the BNP level and LVMI. Without the requirement of a special technique, this evaluation might indicate potential cardiac overload and provide a clinical sign related to heart failure.

Lipid Peroxides in the Mechanism of Ischemia/Reperfusion Injury in Skeletal Muscle—Experimental Studies

Two sets of experiments were conducted to investigate whether oxygen-de rived free radicals are involved in the mechanism of ischemia/reperfusion (I/R) injury of skeletal muscle and vitamin E is effective in alleviating the injury.

In the first set of experiments, twenty adult mongrel dogs were divided into three groups: group 1 (n=7) control, group 2 (n = 6) I/R, and group 3 (n=7) I/R with 500 mg of vitamin E. Serum creatine phosphokinase (CPK) and lipid per oxides (LPO) were measured as markers of rhabdomyolysis and biomembrane injury due to oxygen-derived free radicals, respectively. CPK increased signifi cantly after reperfusion with a peak value of 38,000 ± 9,800 mU/mL in group 2, when compared with a peak value of 1,060 ± 290 mU/mL in group 3 (p < 0.02). LPO also significantly increased with a peak value of 20.4 ±3.7 nmol/mL in group 2, when compared with a peak value of 9.2 ± 2.2 nmol/mL in group 3 (p < 0.04).

In the second sets of experiments, 13 dogs were divided into two groups: group A (n=5) control and group B (n=8) I/R. Tissue LPO was measured eighteen hours after reperfusion in the gracilis muscle and gastrocnemius mus cle. The mean value of LPO in the gracilis muscle was 0.94 ± 0.46 nmol/mg protein in group A, compared with 1.13 ± 0.67 nmol/mg protein in group B. It was higher in group B, but there was no significant difference. Mean LPO in the gastrocnemius muscle was 0.85 ± 0.34 nmol/mg protein in group A, and 1.83 ± 0.71 nmol/mg protein in group B. There was a significant difference (p < 0.02).

Serum CPK and LPO were significantly higher in group 2 than in groups 1 and 3, and tissue LPO was also high in skeletal muscle after reperfusion. Serum CPK and LPO were effectively suppressed by administration of vitamin E be fore reperfusion.

These results show that oxygen-derived free radicals are involved in the mechanism of I/R injury in skeletal muscle and suggest that vitamin E is effec tive in alleviating the injury.

Effect of silane and phosphate primers on the adhesive performance of a tri-n-butylborane initiated luting agent bonded to zirconia

The purpose of this study was to evaluate the effects of primers on the bond strength and durability of an acrylic resin luting agent bonded to zirconia. Disk specimens were fabricated from zirconia partially stabilized with yttrium oxide. The disks were primed with one of the following materials: Alloy Primer (AP), Ceramic Primer (CP), Liquid A of the Porcelain Liner M (PLM-A), Liquid B of Porcelain Liner M (PLM-B), Porcelain Liner M (PLM-A+PLM-B), Monobond Plus (MP), and mixture of AP and PLM-B. The specimens were bonded with a tri-n-butylborane (TBB)-initiated luting agent. The shear bond strengths were determined both before and after thermocycling. The results were statistically analyzed with a non-parametric procedure. The highest post-thermocycling bond strength was generated from the groups primed with MP, CP, and AP. It can be concluded that the application of three phosphate primers is recommended for bonding the zirconia with the TBB-initiated luting agent.

Adhesive performance of silver-palladium-copper-gold alloy and component metals bonded with organic sulfur-based priming agents and a tri-n-butylborane initiated luting material

OBJECTIVE

The purpose of the current study was to evaluate the effect of thione-based metal priming agents on the adhesive behavior of a Ag-Pd-Cu-Au alloy and component metals bonded with an acrylic resin.

MATERIALS AND METHODS

Disk specimens (10 mm in diameter by 3 mm thick) were prepared from a silver-palladium-copper-gold (Ag-Pd-Cu-Au) alloy (Castwell M.C.12), high-purity silver, palladium, copper and gold. Four single-liquid priming agents containing organic sulfur compound (Alloy Primer, Metaltite, M.L. Primer and V-Primer) and three acidic priming agents (All Bond II Primer B, Estenia Opaque Primer and Super-Bond Liquid) were assessed. The metal specimens were flat-ground with abrasive papers, primed with one of the agents and bonded with a tri-n-butylborane initiated resin. The shear bond strengths were determined both before and after repeated thermocycling (5°C and 55°C, 1 min each, 20,000 cycles). The results were statistically analyzed with a non-parametric procedure (p = 0.05 level).

RESULTS

The post-thermocycling bond strengths in MPa (median; n = 11) associated with the Alloy Primer, Metaltite, M.L. Primer and V-Primer materials were, respectively, 20.8, 22.8, 17.8 and 18.4 for the Ag-Pd-Cu-Au alloy; 19.6, 21.9, 14.4 and 20.1 for silver; 5.4, 4.5, 12.8 and 5.3 for palladium; 17.1, 19.2, 0.7 and 6.6 for copper; and 18.5, 17.7, 22.8 and 15.4 for gold.

CONCLUSIONS

It can be concluded that the use of the four priming agents, which are based on organic sulfur compounds, effectively enhanced bonding to the Ag-Pd-Cu-Au alloy and the component metals, although the bonding performance varied among the priming agents and metal elements. The priming agents appeared to have more of an effect on the alloy, silver and gold than on the palladium and copper.

20β-hydroxysteroid dehydrogenase gene promoter: potential role for cyclic AMP and xenobiotic responsive elements

Teleostean 20β-hydroxysteroid dehydrogenase (20β-HSD) is involved in final oocyte maturation and steroid hormone metabolism. It has structural and functional similarities to mammalian carbonyl reductases that are involved in the metabolism of endogenous carbonyl and xenobiotic compounds. To understand the transcriptional regulation of 20β-HSD, here we report the cloning of 20β-HSD promoter from two fish species, rainbow trout and air-breathing catfish. Analysis of the promoter motifs, in silico identified the presence of several sites for transcription factor binding including cAMP, xenobiotic and steroid hormone responsive elements. Luciferase reporter assays with progressive deletion constructs demonstrated that 20β-HSD type B of trout has no promoter activity while 20β-HSD type A of trout and catfish 20β-HSD promoters showed basal promoter activity. A TATA box flanked by a CAAT box is important for basal transcription. Deletion of cAMP responsive element in the promoter decreased basal promoter activity significantly. Reporter assays with forskolin and IBMX, drugs that increase intracellular cAMP induced the promoter activity over the basal level. Intriguingly, β-nafthoflavone, an arylhydrocarbon receptor ligand, induced the 20β-HSD promoter activity and is further evidenced by the induction of 20β-HSD expression in the livers of catfish, in vivo. These results demonstrate for the first time that 20β-HSD expression is not only modulated by cAMP but also by xenobiotics and further studies may provide significance to the ubiquitous distribution and broad substrate specificity of this enzyme.

Identification of a functional luciferase gene in the non-luminous diurnal firefly, Lucidina biplagiata

We isolated a luciferase gene (LbLuc) from the non-luminous diurnal firefly, Lucidina biplagiata, with high similarity to that from the nocturnal firefly, Photinus pyralis. The recombinant LbLuc showed luminescence activity comparable to that of the luciferases from P. pyralis and Luciola cruciata. To understand the non-luminosity of L. biplagiata, we determined the amount of luciferase in the adult specimen using the luciferin-luciferase reaction and found that the content of luciferase in L. biplagiata was estimated to be only 0.1% of that in L. cruciata. As previously reported, the content of luciferin in L. biplagiata was less than 0.1% of that in L. cruciata. Thus, the non-luminosity of L. biplagiata might be explained by low levels of both luciferase and luciferin.

Identification of genes related to mechanical stress in human periodontal ligament cells using microarray analysis

BACKGROUND AND OBJECTIVE

Differential expression of genes in human periodontal ligament (PDL) under mechanical stress, such as orthodontic force, is thought to be involved in the remodeling of PDL cells and periodontal tissues. However, little is known about the genes expressed in PDL cells under mechanical stress.

MATERIAL AND METHODS

We employed microarray analysis to assess, in a comprehensive manner, the gene expression profiles in PDL cells compressed by a static force using an in vitro three-dimensional culture system. Six genes were selected and validated by quantitative real-time polymerase chain reaction analysis, consistent with the microarray data.

RESULTS

The microarray data revealed that 108 of 30,000 genes tested were differentially expressed by mechanical force loading. Among them, 85 genes were up-regulated by mechanical stress, while 23 genes were down-regulated, judging by the thresholds of a two-fold increase/decrease compared with the controls. Thirty-two of the up-regulated and eight of the down-regulated genes, well-characterized in protein function, were involved in numerous biological processes including cell communication, cell signaling, cell cycle, stress response, and calcium release. However, several genes differentially expressed in our microarray data have not been well defined as stress-response molecules.

CONCLUSION

Our microarray is the first to show the gene profile in PDL cells caused by mechanical stress; however, further studies to clarify the physiological function of these molecules in PDL cells are required.

Cloning and characterization of the homologous genes of firefly luciferase in the mealworm beetle, Tenebrio molitor

Three homologous genes of firefly luciferase were cloned from the non-luminous beetle Tenebrio molitor. Three gene products for homologues, TmLL-1, TmLL-2 and TmLL-3, showed fatty acyl-coenzyme A (acyl-CoA) synthetic activity, but not luciferase activity with firefly luciferin. The transcripts were detected through the developmental stages in T. molitor. These results suggested that firefly luciferase was evolved from a fatty acyl-coenzyme A synthetase by gene duplications in the insect.

Effects of modification at the fifth residue of mu-conotoxin GIIIA with bulky tags on the electrically stimulated contraction of the rat diaphragm

Mu-conotoxin GIIIA, a peptide toxin from the cone snail, blocks muscle-type sodium channels. Thr-5 of mu-conotoxin GIIIA, located on the opposite side of the active site in the globular molecule, was replaced by Cys to which the bulky tags were attached. The tagged mu-conotoxin GIIIA derivatives, except for the phospholipid-tagged one, exerted the biological activity with a potency slightly weaker than natural mu-conotoxin GIIIA. When the biotinylated tags of various lengths were added, the presence of avidin suppressed the action of the biotinylated toxins of <4 nm, but not with 5 nm. The bulky biotinylated tags are useful as a caliper to measure the depth of receptor sites in the channels.