Effect of Insufficient Light Exposure on Polymerization Kinetics of Conventional and Self-adhesive Dual-cure Resin Cements

Objectives: The purpose of this study was to investigate the influence of insufficient light exposure on the polymerization of conventional and self-adhesive dual-cure resin cements under ceramic restorations.

Methods: Two conventional dual-cure resin cements (Rely-X ARC, Duolink) and two self-adhesive resin cements (Rely-X U200, Maxcem Elite) were polymerized under different curing modes (dual-cure or self-cure), curing times (20 and 120 seconds), and thickness of a ceramic overlay (2 and 4 mm). Polymerization kinetics was measured by Fourier transform infrared spectroscopy for the initial 10 minutes and after 24 hours. Data were analyzed using mixed model analysis of variance (ANOVA), one-way ANOVA/Student-Newman-Keuls post hoc test, and paired t-test (α=0.05).

Results: When light-curing time was set to 20 seconds, the presence of the ceramic block significantly affected the degree of conversion (DC) of all resin cements. Especially, the DC of the groups with 20 seconds of light-curing time under 4 mm of ceramic thickness was even lower than that of the self-cured groups at 24 hours after polymerization (p<0.05). However, when light-curing time was set to 120 seconds, a similar DC compared with the group with direct light exposure (p>0.05) was achieved in all dual-cure groups except Maxcem Elite, at 24 hours after polymerization.

Conclusions: For both conventional and self-adhesive dual-cure resin cements, insufficient light exposure (20 seconds of light-curing time) through thick ceramic restoration (4 mm thick) resulted in a DC even lower than that of self-curing alone.

Distribution of Porcine Endogenous Retrovirus in Different Organs of the Hybrid of a Landrace and a Jeju Domestic Pig in Korea

Xenotransplantation offers a solution to the shortage of available organs for transplantation, and the pig represents an ideal source of such organs. However, porcine endogenous retrovirus (PERV), whose genome is integrated in pigs, has been suggested to pose a potential risk of xenotransmission. Expression of PERVs in different organs of pigs was carefully measured at DNA, mRNA, and protein levels, providing information valuable for the application of pig organs in xenotransplantation. An analysis of PERV DNA showed that a very similar number of PERV copies was present in the genome of all organs, whereas mRNA and protein levels of PERV varied depending on the organ, with kidney, liver, and spleen expressing high levels of both mRNA and protein. In contrast, mRNA and protein levels were dissimilar in the lung and brain, where mRNA levels were low but protein levels were high. This discrepancy indicates that mRNA levels are not always reflected in protein expression. In addition, the difference between mRNA and protein highlights the importance of choosing the proper analysis method for diagnosing viral infection. In summary, this study provides insight into the distribution of PERV in various organs at the DNA, mRNA, and protein levels, and also informs the proper selection of tissues or organs for future clinical xenotransplantation.

Effects of Palm Kernel Expellers on Productive Performance, Nutrient Digestibility, and White Blood Cells of Lactating Sows

This experiment was conducted to investigate the effects of palm kernel expellers on productive performance, nutrient digestibility, and changes in white blood cells (WBC) of lactating sows. A total of 14 sows (200±12 kg of average body weight [BW]; 2.5 of average parity) were used and moved from gestation room to farrowing room on d 109 of gestation. Sows were randomly assigned to 2 dietary treatments in a completely randomized design. The treatments were a diet based on corn and soybean meal (CON) and CON added with 20% of palm kernel expellers (PKE). Sows were fed the treatments for 28 days (weaning) after farrowing. Blood was collected from each sow and 4 randomly selected piglets from each sow before farrowing or on d 3, 7, or 14 of lactation. Sows were fed respective treatments containing 0.2% chromic oxide from d 15 to 21 of lactation. Fecal samples were collected daily for the last 3 days after the 4-d adjustment period. Measurements were performances and WBC changes of sows and litter, nutrient digestibility of sows, and daily diarrhea of litter. Sows fed PKE had greater average daily feed intake (7.38 vs 7.10 kg/d; p<0.05) and lost less BW (−6.85 vs −8.54 kg; p<0.05) and backfat depth (−0.42 vs −0.71 mm; p<0.05) than those fed CON. However, there were no differences on digestibility of dry matter, nitrogen, and energy and weaning to estrus interval of sows fed either CON or PKE. Piglets from sows fed PKE gained more BW (203 vs 181 g/d; p = 0.08) and had less frequency of diarrhea (6.80 vs 8.56%; p = 0.07) than those from sows fed CON. On the other hand, no difference was found on preweaning mortality of piglets from sows fed either CON or PKE. Sows fed PKE had lower number of WBC (9.57 vs 11.82 ×10³/μL; p = 0.09) before farrowing than those fed CON, but no difference on d 3 and 7. Similarly, piglets from sows fed PKE had also lower number of WBC (7.86 vs 9.80 ×10³/μL; p<0.05) on d 14 of lactation than those from sows fed CON, but no difference on d 3 and 7. In conclusion, addition of 20% palm kernel expellers to lactation diet based on corn and soybean meal had no negative effects on productive performance, nutrient digestibility, and WBC changes of lactating sows.

Effects of Palm Kernel Expellers on Growth Performance, Nutrient Digestibility, and Blood Profiles of Weaned Pigs

This experiment was conducted to investigate the effects of palm kernel expellers on growth performance, nutrient digestibility, and blood profiles of weaned pigs. A total of 88 weaned pigs (6.94±0.76 kg body weight [BW]; 28 d old) were randomly allotted to 2 dietary treatments (4 pigs/pen; 11 replicates/treatment) in a randomized complete block design (sex as a block). The dietary treatments were a typical nursery diet based on corn and soybean meal (CON) and CON added with 20% of palm kernel expellers (PKE). Pigs were fed for 6 wk using a 3-phase feeding program with declining diet complexity and with phases of 1, 2, and 3 wk, respectively. Blood was collected from randomly selected 2 pigs in each pen before weaning and on d 7 after weaning. Pigs were fed respective dietary treatments containing 0.2% chromic oxide from d 29 to 35 after weaning. Fecal samples were collected from randomly selected 2 pigs in each pen daily for the last 3 days after the 4-d adjustment period. Measurements were growth performances, digestibility of dry matter, nitrogen and energy, white and red blood cell counts, packed cell volume, and incidence of diarrhea. The PKE increased average daily gain (ADG) (246 vs 215 g/d; p = 0.06) and average daily feed intake (ADFI) (470 vs 343 g/d; p<0.05) and decreased gain-to-feed ratio (G:F) (0.522 vs 0.628 g/g; p<0.05) during phase 2 compared with CON, but did not affect growth performance during phase 1 and 3. During overall experimental period, PKE increased ADG (383 vs 362 g/d; p = 0.05) and ADFI (549 vs 496 g/d; p<0.05) compared with CON, but did not affect G:F. However, no differences were found on digestibility of dry matter, nitrogen, and energy between CON and PKE. The PKE reduced frequency of diarrhea (15% vs 25%; p = 0.08) for the first 2 wk after weaning compared with CON. Similarly, PKE decreased white blood cells (8.19 vs 9.56×10(3)/μL; p = 0.07), red blood cells (2.92 vs 3.25×10(6)/μL; p = 0.09), and packed cell volume (11.1% vs 12.6%; p = 0.06) on d 7 after weaning compared with CON. In conclusion, addition of 20% palm kernel expellers to nursery diet based on corn and soybean meal had no negative effects on growth performance, nutrient digestibility, and blood profiles of weaned pigs.

γ-Secretase inhibition promotes fibrotic effects of albumin in proximal tubular epithelial cells

BACKGROUND AND PURPOSE

Albuminuria is an important biomarker of renal dysfunction and is a major mediator of renal damage and fibrosis during kidney disease. The mechanisms underlying albumin-induced renal fibrosis remain unclear. There has been significant interest in γ-secretase activity in tubular epithelial cells in recent times; however, its potential role in albumin-induced fibrosis has not been investigated.

EXPERIMENTAL APPROACH

The primary aim of this study was to examine the role of γ-secretase in albumin-induced fibrotic effects in proximal tubular cells. The effects of increasing albumin concentrations on fibrosis indicators and mediators in the human HK-2 cell line were examined in the presence and absence of a γ-secretase inhibitor, compound E.

KEY RESULTS

Treatment with albumin resulted in a number of pro-fibrotic effects, including up-regulation of fibronectin, TGF-β1 and the EGF-R. Interestingly, similar effects were observed in response to treatment with the γ-secretase inhibitor, compound E. Co-treatment of cells with albumin and an EGF-R inhibitor, AG-1478, resulted in significant inhibition of the observed pro-fibrotic effects, suggesting a major role for the EGF-R in albumin-induced fibrotic events. Albumin-induced effects on the EGF-R appeared to be mediated through inhibition of γ-secretase activity and were dependent on ERK-MAPK signalling.

CONCLUSIONS AND IMPLICATIONS

These results provide novel insights into the mechanisms of albumin-induced fibrotic effects in tubular epithelial cells, suggesting important roles for the γ-secretase and the EGF-R. These results suggest that the proposed use of γ-secretase inhibitors as anti-fibrotic agents requires further investigation.

Genetic polymorphisms of CCND1 and PTEN in progression of esophageal squamous carcinoma

Cyclin D1 (CCND1) plays a significant role in G1-S transition of cell cycle, and phosphatase and a tensin homologue (PTEN) negatively regulate cell cycle through phosphatidylinositol 3-kinase (PI3K)/AKT signaling. CCND1 and PTEN genetic polymorphisms might induce susceptibility to the occurrence of esophageal squamous cell carcinoma (ESCC). Three hundred and four ESCC patients and 413 healthy controls from Anyang, China, were enrolled in this study. All genotyping at CCND1 (807 G/A) and PTEN (rs701848 T/C and rs2735343 C/G) were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Unconditional logistic regression model was used to analyze the correlation between the polymorphisms and the susceptibility to develop ESCC. Statistically significant differences were observed between cases and controls in distribution of genotypes or alleles at PTEN rs701848 T/C and rs2735343 C/G, with either haplotype TG or CG possessing notably higher proportion in cases than in the controls. However, such difference could not be found in the distribution of the polymorphisms at CCND1 807 G/A. In summary, the polymorphisms of PTEN rs701848 T/C and rs2735343 C/G might represent crucial modifying factors for development of ESCC.

A randomised, double-blind, parallel design, multi-institutional, non-inferiority phase IV trial of imidafenacin versus fesoterodine for overactive bladder

AIMS

Our objective was to compare the efficacy and safety of imidafenacin over fesoterodine in patients with overactive bladder (OAB).

METHODS

This study is a randomised, double-blind, parallel-group, fesoterodine-controlled study in patients with continuous OAB symptoms for ≥ 3 months, daily mean voiding frequency (DMVF) ≥ 8, and daily mean urgency or urgency incontinence frequency ≥ 2. A twice-daily 0.1 mg imidafenacin with placebo, or once-daily 4 mg fesoterodine with placebo were administered for 12 weeks. The primary efficacy end-point was the difference in DMVF at 12 weeks. The secondary efficacy end-points were differences in daily mean: (i) voiding frequency at 4 and 8 weeks; (ii) urgency frequency; (iii) urgency incontinence frequency; (iv) incontinence frequency; (v) nocturia frequency; and (vi) quality of life score. The variables for safety analysis were adverse events, vital signs, residual urine volume and clinical laboratory tests. An efficacy analysis was conducted in per-protocol patients and the safety analysis was conducted in all randomised patients.

RESULTS

The differences in DMVF at 12 weeks were -3.38 ± 3.63 and -2.45 ± 3.73 in the imidafenacin and fesoterodine groups, respectively, and the difference was not significant between the two groups. Imidafenacin was non-inferior to fesoterodine, and the lower limit of 95% two-sided confidence intervals was -0.53. The other six secondary end-points and variables for safety analysis showed no difference between the two groups.

CONCLUSIONS

Imidafenacin was non-inferior to fesoterodine in terms of efficacy, and showed no significant difference in terms of safety.

Anatomical investigations for appropriate needle positioning for thoracic paravertebral blockade in children

OBJECTIVE

Clinicians hesitate to perform thoracic paravertebral blockade (TPVB) in children due to the potential high risk of adverse effects. No paediatric anatomical guidelines for TPVB exist. This study aimed to estimate the appropriate depth and distance for safe needle positioning in children.

METHODS

The depth (D) from the skin to the paravertebral space and the distance (A) from the spinous process to the needle entry point on the skin were measured using chest computed tomography (CT) in children aged between 1 and 9 years. Correlations between age, gender, weight, height, body mass index (BMI) and each of the anatomical measurements were analysed.

RESULTS

Each measurement correlated significantly with age, weight and height, but not with BMI (n = 373 children). Measurements A and D could be calculated by: A = 13.56 + (0.33 × age [years]) + (0.06 × weight [kg]) + 0.47 × (gender [female = 0, male = 1]); and D = 17.49 - (0.35 × age [years]) + (0.55 × weight [kg]).

CONCLUSION

These anatomical guidelines for TPVB are recommended to help prevent anaesthetic complications such as pneumothorax, when ultrasonography and CT are unavailable.

Overweight and its association with aortic pressure wave reflection after exercise

BACKGROUND

Obesity is associated with arterial stiffening, left ventricular (LV) hypertrophy, and diastolic dysfunction. However, there is no data regarding dynamic changes in arterial hemodynamics with exercise in overweight subjects. We hypothesized that overweight women would show a different exercise response in wave reflection compared with lean women.

METHODS

A total of 59 overweight and 68 lean nondiabetic women (mean age 63 ± 7 years) underwent symptom-limited supine bicycle exercise testing with simultaneous two-dimensional and Doppler echocardiography. Central hemodynamics including central aortic pressure and augmentation index (AIx) were obtained at rest and immediately after peak exercise using radial artery tonometry.

RESULTS

Overweight women showed a higher LV mass index (lean vs. overweight; 40.2 ± 10.2 vs. 45.3 ± 11.0 g/m(2.7), P = 0.007) and a lower early diastolic mitral annular velocity (6.3 ± 1.8 vs. 5.5 ± 1.6 cm/s, P = 0.013) than lean women. Although the two groups did not differ in peripheral and central hemodynamics including AIx (36.3 ± 11.7 vs. 36.8 ± 10.2%, P = 0.830) and AIx normalized for heart rate 75/min (AIx@75, 30.4 ± 11.5 vs. 30.1 ± 9.9%, P = 0.885) at rest, AIx (20.9 ± 11.5 vs. 27.6 ± 10.4%, P = 0.004) and AIx@75 (25.8 ± 10.2 vs. 31.6 ± 7.7%, P = 0.002) at peak exercise were significantly higher in overweight women. In simple correlation analysis, body mass index (BMI) showed significant correlations with AIx, and AIx@75 at peak exercise, whereas no relationships were found with those parameters at rest. Multiple regression analysis showed that BMI was an independent determinant of AIx@75 at peak exercise (β = 0.28, P = 0.004).

CONCLUSIONS

Despite similar resting peripheral and central hemodynamics, the wave reflection in overweight women after exercise differed from that in lean women. These findings suggest that being overweight is related to higher wave reflection after exercise.