Comparative adherence of macitentan versus ambrisentan and bosentan in Australian patients with pulmonary arterial hypertension: a retrospective real-world database study

AIM

Bosentan, ambrisentan, and macitentan are endothelin receptor antagonists (ERAs), currently available in Australia for treatment of pulmonary arterial hypertension (PAH). This study assessed the comparative adherence of these ERAs for PAH in Australian patients.

METHODS

This retrospective, observational study used data for adults with PAH from the Services Australia 10% Pharmaceuticals Benefits Scheme (PBS) dataset (01/2006-10/2020). The primary outcome was treatment adherence (i.e. receiving ≥80% of ERA doses over 12 months). Secondary outcomes were time to treatment change (add-on or switch) and overall survival.

RESULTS

The study included 436 patients who took bosentan (n = 200), ambrisentan (n = 69), or macitentan (n = 167). Treatment adherence was significantly greater in patients who received macitentan (65.3%) versus ambrisentan (56.5%) and bosentan (58.0%), with odds ratios (ORs; 95% CI) of 0.51 (0.30-0.88; p = 0.016) for bosentan versus macitentan and 0.48 (0.24-0.96; p = 0.037) for ambrisentan versus macitentan. The median time to treatment change was 47.2 and 43.4 months for bosentan and ambrisentan, respectively (not calculated for macitentan because of insufficient duration of data).

LIMITATIONS AND CONCLUSIONS

Real-world data for Australian patients with PAH showed that treatment adherence for ERAs was suboptimal. Adherence was higher for macitentan compared with ambrisentan and bosentan.

Comparative Treatment Persistence and Adherence to Endothelin Receptor Antagonists Among Patients with Pulmonary Arterial Hypertension in Japan: A Real-World Administrative Claims Database Study

INTRODUCTION

Real-world data on the comparative effectiveness of endothelin receptor antagonists (ERAs; macitentan, bosentan, ambrisentan) for pulmonary arterial hypertension (PAH), particularly in Asian countries, are scarce. We evaluated the persistence of these ERAs before and after macitentan approval in Japan (2015).

METHODS

We used real-world data from the Japanese Medical Data Vision administrative claims database between April 2008 and November 2020. Patients with PAH were identified from the dataset. Persistence to ERA treatment before and after approval of macitentan in Japan was defined as the time between start of the index ERA and treatment discontinuation or death. Propensity score adjustment was applied to minimize confounding effects among treatment groups.

RESULTS

In the pre-macitentan approval cohort, 153 and 51 patients received bosentan and ambrisentan, respectively. In the post-macitentan approval cohort, 331, 284, and 91 patients received macitentan, bosentan, and ambrisentan, respectively. Unadjusted median persistence for ambrisentan- and bosentan-treated patients was 19 and 10 months, respectively (adjusted HR 0.87 [95% CI 0.61-1.24]; P = 0.434 [bosentan as reference]). In the post-macitentan approval cohort, unadjusted median persistence was 18 months for macitentan-treated patients versus 6 and 8 months for ambrisentan- and bosentan-treated patients, respectively. Adjusted HRs for ambrisentan and bosentan were 1.48 (95% CI 1.12-1.95; P = 0.006) and 1.63 (95% CI 1.30-2.04; P < 0.001 [macitentan as reference]), respectively.

CONCLUSIONS

Real-world data for Japanese patients with PAH showed that persistence was significantly higher for macitentan, versus ambrisentan and bosentan, since its approval.

Amivantamab compared with real-world therapies in patients with advanced non-small cell lung cancer EGFR Exon 20 insertion mutations after platinum-based chemotherapy

BACKGROUND

In the single-arm CHRYSALIS trial, advanced non-small cell lung cancer patients harboring epidermal growth factor receptor (EGFR) exon 20 insertion (Exon 20ins) showed durable responses to amivantamab, an EGFR-MET bispecific antibody targeting tumors with EGFR Exon 20ins. This study compared the effectiveness of amivantamab to real-world systemic anti-cancer therapies in Japan.

PATIENTS AND METHODS

External control patients were selected by applying CHRYSALIS eligibility to Japanese patients from LC-SCRUM-Asia. External control patients were included for every qualifying line of therapy after platinum-based chemotherapy. Propensity score weighting was applied to external control patients to adjust for differences in baseline characteristics. Outcomes were compared between external control patients, and all and Asian-only CHRYSALIS patients using weighted Cox proportional hazards regression models for progression-free survival (PFS), time to next therapy (TTNT), and overall survival (OS), and generalized estimating equations with repeated measurements for overall response rate (ORR).

RESULTS

One hundred fifteen CHRYSALIS and 94 external control patients were identified. Compared to external control patients, amivantamab-treated patients had significantly longer OS (median OS 19.88 vs 14.09 months, HR [95% CI] 0.59 [0.40-0.88]), PFS (median PFS 6.74 vs 4.73 months, HR 0.59 [0.45-0.78]), TTNT (median TTNT 12.16 vs 5.09 months, HR 0.39 [0.29-0.53]), and significantly higher ORR (41.7% vs 14.1%). Analyses of amivantamab-treated Asian patients (n = 61) showed similar clinical benefits.

CONCLUSION

In the absence of clinical evidence from randomized clinical trials, this study reflects the benefit of amivantamab after platinum-based chemotherapy for advanced non-small cell lung cancer patients harboring EGFR Exon 20ins, compared to current real-world therapies.

Prevalence, patient characteristics and treatment patterns among SLE-PAH patients in real-world clinical practice: A retrospective analysis of Medical Data Vision Database in Japan

OBJECTIVE

Real-world evidence regarding prevalence, patient characteristics and treatment patterns for pulmonary arterial hypertension (PAH) related to systemic lupus erythematosus (SLE) in Japan is limited.

METHODS

We conducted a retrospective study analysing Japan's Medical Data Vision (MDV) database from April-2008 to September-2020. Prevalence, incidence, patient characteristics, treatment patterns and use of vasodilators by treatment line were evaluated.

RESULTS

Prevalence of PAH was 0.392% in SLE patients (n=114/29,077). Cumulative incidence was 0.53% (3-years (y)) and 0.77% (5y). Of 114 SLE-PAH patients, 49% developed PAH <1 year from SLE diagnosis. SLE-PAH patients were more female (88% vs. 72%), had lower mean age at SLE diagnosis (53y vs. 56y) and more severe SLE (61% vs 25%), versus non-PAH SLE patients. Glucocorticoids (58%) and vasodilators (27%) were preferred first-line monotherapy for SLE-PAH. Glucocorticoids+immunosuppressants (19%) was predominant first-line combination therapy. Endothelin receptor antagonists (40% and 44%) and nitric oxide analogues (31% and 40%) were dominant first- and second-line vasodilators.

CONCLUSION

SLE-PAH patients were more females, younger at diagnosis, had more severe SLE than non-PAH SLE patients. Most were diagnosed <1 year of SLE diagnosis. In Japan's real-world practice, initial treatment goal is SLE management, while vasodilators are preferred in advanced disease, as per MDV database.

A retrospective study on the incidence, management and risk factors of skin rash in patients with advanced prostate cancer in Japan

BACKGROUND

Worldwide, prostate cancer (PC) is the second most diagnosed cancer and the fifth leading cause of cancer death in men. Hormonal therapies, commonly used for PC, are associated with a range of treatment-emergent adverse events (TEAEs). The population from Japan seems to be at higher risk of developing TEAEs of skin rash compared to the overall global population. This study was conducted to get a better insight into the incidence, management, and risk factors for skin rash during active treatment for advanced PC in Japan.

METHODS

A retrospective cohort of PC patients was identified and subsequently categorized, into non-metastatic and metastatic castration-resistant prostate cancer patients (nmCRPC and mCRPC), and metastatic castration-naïve prostate cancer patients (mCNPC). The analysis was based on a dataset from the Medical Data Vision (MDV) database. Descriptive statistics were determined, and a multivariate Cox proportional hazards model was used to the associated risk factors for the onset of rash.

RESULTS

Overall, 1,738 nmCRPC patients, 630 mCRPC patients, and 454 mCNPC patients were included in this analysis. The median age was 78 years old and similar across the three cohorts. The skin rash incidence was 19.97% for nmCRPC cohort, 28.89% for mCRPC cohort, and 28.85% for mCNPC cohort. The median duration of skin rash ranged from 29 to 42 days. Statistically significant risk factors for developing skin rash included a history of allergy or hypersensitivity (all cohorts), increased age (nmCRPC and mCRPC), a body mass index (BMI) of < 18.5 (nmCRPC and mCRPC), and a PSA level higher than the median (nmCRPC). Skin rash was commonly managed with systemic and topical corticosteroids which ranged from 41.76% to 67.03% for all cohorts. Antihistamines were infrequently used.

CONCLUSION

This study provides a better understanding of the real-world incidence, onset, duration, management and risk factors of skin rash in patients on active PC treatment in Japan. It was observed that approximately 20-30% of PC patients experience skin rash. Development of skin rash was associated with previous allergy or hypersensitivity, BMI of < 18.5, increased age and higher PSA levels, and was usually treated with corticosteroids.

[Safety and efficacy of the early administration of levosimendan in patients with acute non-ST-segment elevation myocardial infarction and elevated NT-proBNP levels: An Early Management Strategy of Acute Heart Failure (EMS-AHF)]

Objectives: To investigated the safety and efficacy of treating patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and elevated levels of N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP) with levosimendan within 24 hours of first medical contact (FMC). Methods: This multicenter, open-label, block-randomized controlled trial (NCT03189901) investigated the safety and efficacy of levosimendan as an early management strategy of acute heart failure (EMS-AHF) for patients with NSTEMI and high NT-proBNP levels. This study included 255 patients with NSTEMI and elevated NT-proBNP levels, including 142 males and 113 females with a median age of 65 (58-70) years, and were admitted in the emergency or outpatient departments at 14 medical centers in China between October 2017 and October 2021. The patients were randomly divided into a levosimendan group (n=129) and a control group (n=126). The primary outcome measure was NT-proBNP levels on day 3 of treatment and changes in the NT-proBNP levels from baseline on day 5 after randomization. The secondary outcome measures included the proportion of patients with more than 30% reduction in NT-proBNP levels from baseline, major adverse cardiovascular events (MACE) during hospitalization and at 6 months after hospitalization, safety during the treatment, and health economics indices. The measurement data parameters between groups were compared using the t-test or the non-parametric test. The count data parameters were compared between groups using the χ² test. Results: On day 3, the NT-proBNP levels in the levosimendan group were lower than the control group but were statistically insignificant [866 (455, 1 960) vs. 1 118 (459, 2 417) ng/L, Z=-1.25,P=0.21]. However, on day 5, changes in the NT-proBNP levels from baseline in the levosimendan group were significantly higher than the control group [67.6% (33.8%,82.5%)vs.54.8% (7.3%,77.9%), Z=-2.14, P=0.03]. There were no significant differences in the proportion of patients with more than 30% reduction in the NT-proBNP levels on day 5 between the levosimendan and the control groups [77.5% (100/129) vs. 69.0% (87/126), χ²=2.34, P=0.13]. Furthermore, incidences of MACE did not show any significant differences between the two groups during hospitalization [4.7% (6/129) vs. 7.1% (9/126), χ²=0.72, P=0.40] and at 6 months [14.7% (19/129) vs. 12.7% (16/126), χ²=0.22, P=0.64]. Four cardiac deaths were reported in the control group during hospitalization [0 (0/129) vs. 3.2% (4/126), P=0.06]. However, 6-month survival rates were comparable between the two groups (log-rank test, P=0.18). Moreover, adverse events or serious adverse events such as shock, ventricular fibrillation, and ventricular tachycardia were not reported in both the groups during levosimendan treatment (days 0-1). The total cost of hospitalization [34 591.00(15 527.46,59 324.80) vs. 37 144.65(16 066.90,63 919.00)yuan, Z=-0.26, P=0.80] and the total length of hospitalization [9 (8, 12) vs. 10 (7, 13) days, Z=0.72, P=0.72] were lower for patients in the levosimendan group compared to those in the control group, but did not show statistically significant differences. Conclusions: Early administration of levosimendan reduced NT-proBNP levels in NSTEMI patients with elevated NT-proBNP and did not increase the total cost and length of hospitalization, but did not significantly improve MACE during hospitalization or at 6 months.

Correlation between retinal vein pulse amplitude, estimated intracranial pressure, and postural change

Spaceflight associated neuro-ocular syndrome (SANS) is common amongst astronauts on long duration space missions and is associated with signs consistent with elevated cerebrospinal fluid (CSF) pressure. Additionally, CSF pressure has been found to be elevated in a significant proportion of astronauts in whom lumbar puncture was performed after successful mission completion. We have developed a retinal photoplethysmographic technique to measure retinal vein pulsation amplitudes. This technique has enabled the development of a non-invasive CSF pressure measurement apparatus. We tested the system on healthy volunteers in the sitting and supine posture to mimic the range of tilt table extremes and estimated the induced CSF pressure change using measurements from the CSF hydrostatic indifferent point. We found a significant relationship between pulsation amplitude change and estimated CSF pressure change (p < 0.0001) across a range from 2.7 to 7.1 mmHg. The increase in pulse amplitude was highest in the sitting posture with greater estimated CSF pressure increase (p < 0.0001), in keeping with physiologically predicted CSF pressure response. This technique may be useful for non-invasive measurement of CSF pressure fluctuations during long-term space voyages.

Assessing the correlation between second progression-free survival (PFS2) and overall survival (OS) in advanced prostate cancer patients using medical data vision (MDV) claims database in Japan

OBJECTIVE

To assess the correlation between PFS2 and OS among patients with advanced prostate cancer (PC) in a real-world setting for Japan.

METHODS

This was a retrospective analysis using the Japanese MDV database. Patients with nmCRPC (non-metastatic Castration-Resistant PC), mCRPC (metastatic Castration-Resistant PC), and mCNPC (metastatic Castration-Naïve PC) were identified and their medical records were investigated for PFS2 and death. Association between PFS2 and OS was determined using the Pearson's, Spearman's, Kendall's Tau, and Fleischers' correlation coefficients.

RESULTS

A total of 386,484 patients with PC were identified from the database, of which, 1,783 patients with nmCRPC, 630 with mCRPC, and 454 with mCNPC met the predefined eligibility criteria. Significant correlation between PFS2 and OS was observed in patients with nmCRPC (Pearson's r = 0.873; 95% CI: 0.849-0.897, Spearman's r = 0.909; 95% CI: 0.893-0.925; Kendall's Tau r = 0.831; 95% CI: 0.812-0.850, Fleischers' r = 0.682; 95% CI: 0.601-0.764), mCRPC (Pearson's r = 0.812; 95% CI: 0.758-0.865, Spearman's r = 0.895; 95% CI: 0.868-0.923, Kendall's Tau r = 0.789; 95% CI: 0.755-0.823, Fleischers' r= 0.439; 95% CI: 0.334-0.544), and mCNPC (Pearson's r = 0.931; 95% CI: 0.899-0.964, Spearman's r = 0.943; 95% CI: 0.922-0.964, Kendall's Tau r = 0.866; 95% CI: 0.836-0.896, Fleischers' r = 0.756; 95% CI: 0.624-0.888).

CONCLUSIONS

The results of this study indicate a significant correlation between PFS2 and OS, which adds additional evidence to the existing literature of using PFS2 as a surrogate endpoint for OS in patients with PC.

Zero retinal vein pulsation amplitude extrapolated model in non-invasive intracranial pressure estimation

Intracranial pressure (ICP) includes the brain, optic nerve, and spinal cord pressures; it influences blood flow to those structures. Pathological elevation in ICP results in structural damage through various mechanisms, which adversely affects outcomes in traumatic brain injury and stroke. Currently, invasive procedures which tap directly into the cerebrospinal fluid are required to measure this pressure. Recent fluidic engineering modelling analogous to the ocular vascular flow suggests that retinal venous pulse amplitudes are predictably influenced by downstream pressures, suggesting that ICP could be estimated by analysing this pulse signal. We used this modelling theory and our photoplethysmographic (PPG) retinal venous pulse amplitude measurement system to measure amplitudes in 30 subjects undergoing invasive ICP measurements by lumbar puncture (LP) or external ventricular drain (EVD). We estimated ICP from these amplitudes using this modelling and found it to be accurate with a mean absolute error of 3.0 mmHg and a slope of 1.00 (r = 0.91). Ninety-four percent of differences between the PPG and invasive method were between − 5.5 and + 4.0 mmHg, which compares favourably to comparisons between LP and EVD. This type of modelling may be useful for understanding retinal vessel pulsatile fluid dynamics and may provide a method for non-invasive ICP measurement.

Differences in Clinical Responses to Ustekinumab Treatment among Body Regions: Results from a Real-World Prospective, Observational, and Multi-Center Study in Korea

Background

Objective

Methods

Results

Conclusion

Clinical outcomes in adult patients with plaque psoriasis treated with ustekinumab under real-world practice in Korea: A prospective, observational, multi-center, postmarketing surveillance study

Postmarketing surveillance is conducted to establish drug safety and effectiveness under real-world practice. We aimed to validate the effectiveness and safety of ustekinumab in the treatment of adult Korean patients with plaque psoriasis under real-world practice. This was a prospective, observational, and multi-center study. Subjects aged 18 years or older who were treated with ustekinumab for plaque psoriasis were enrolled. We enrolled 977 patients; 654 (66.9%) were men, with mean body surface area (BSA, ± standard deviation) of 27.0 ± 18.3% and mean psoriasis area severity index (PASI) score of 18.1 ± 9.7. The effectiveness analysis was performed in 581 patients who had at least one follow-up assessment and met treatment criteria per local label and reimbursement guidelines. Of these patients, 287 had effectiveness data for visit 6 at 53.7 ± 2.1 weeks. At visit 6, 91.6% (263/287), 51.2% (147/287), and 9.4% (27/287) patients achieved PASI 75, 90, and 100 responses, respectively. Adverse events (AEs) occurred in 112 of the 977 (11.5%) patients with an incidence rate of 21.5 per 100 patient-years (PYs). Serious AEs occurred in eight (0.8%) patients with an incidence rate of 1.2 per 100 PYs. The estimated 1-year drug survival rate was 87.7%. The multiple logistic regression analysis showed that higher baseline PASI score and no prior biologic exposure were significant predictors for PASI 90 response at visit 6. Ustekinumab was effective and safe, and displayed a high survival rate in the treatment of adult Korean patients with plaque psoriasis in real-world practice.

Efficacy and safety of guselkumab compared with placebo and adalimumab in Korean patients with moderate-to-severe psoriasis: post-hoc analysis from the phase III, double-blind, placebo- and active-comparator-controlled VOYAGE 1/2 trials

Background: The phase 3 studies, VOYAGE 1 and 2, were conducted to assess guselkumab in the treatment of patients with moderate-to-severe psoriasis.Objectives: To investigate the efficacy and safety of guselkumab in Korean patients.Methods: The Korean sub-population of VOYAGE 1 and 2 study patients were included in this analysis. Efficacy and safety were evaluated through Weeks 24 and 28, respectively.Results: Of 126 randomized Korean patients, 30, 63, and 33 received placebo, guselkumab, and adalimumab, respectively. At Week 16, guselkumab was superior to placebo in achieving an Investigator's Global Assessment (IGA) score of 0 or 1 (cleared or minimal; 90.5 vs. 20.0%, p<.001) and a Psoriasis Area and Severity Index (PASI) 90 response (71.4 vs. 3.3%, p<.001). At week 24, a significantly higher proportion of guselkumab-treated patients achieved PASI 75 and IGA 0 (clear skin) responses compared to adalimumab-treated patients (PASI 75: 93.7 vs. 66.7%, p<.001; IGA 0: 52.4 vs. 21.2%, p=.004). Through Week 28, guselkumab and adalimumab showed comparable safety profiles.Conclusion: The efficacy and safety of guselkumab in Korean psoriasis patients through 28 weeks were consistent with findings for the overall VOYAGE 1 and 2 study population.

Organic trace minerals improve eggshell quality by improving the eggshell ultrastructure of laying hens during the late laying period

The objective of this study was to investigate the effects of low inclusion levels of organic trace minerals (iron, copper, manganese, and zinc) on performance, eggshell quality, serum hormone levels, and enzyme activities of laying hens during the late laying period. A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replications per treatment and 15 birds per replication. The dietary treatments included a basal diet supplemented with inorganic trace minerals at commercial levels (CON), a basal diet supplemented with inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet supplemented with proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted 56 D (8 wk). Compared with the CON group, the ITM group showed decrease in (P < 0.05) egg production, eggshell strength, eggshell palisade layer, palisade layer ratio, serum estrogen, luteinizing hormone, glycosaminoglycan concentration, and carbonic anhydrase activity and increase in (P < 0.05) egg loss and mammillary layer ratio. However, the TRT group almost kept all the indices close to the CON group (P > 0.05). Furthermore, hens fed with low inclusion levels of organic trace minerals had smaller mammillary knobs (P < 0.05) than those in the CON and ITM groups. In conclusion, hens fed with low inclusion levels of proteinated trace minerals had better performance and eggshell strength than those fed with identical levels of inorganic compounds; organic trace minerals improved eggshell quality by improving the eggshell ultrastructure of laying hens during the late laying period.

Usefulness of the Psoriatic Arthritis Screening and Evaluation Questionnaire to Monitor Disease Activity in Management of Patients with Psoriasis: Findings from the EPI-PSODE Study

Background

Psoriasis and psoriatic arthritis (PsA) are included in the group of immune-mediated inflammatory diseases (IMIDs) caused by systemic inflammation; however, indicators for monitoring inflammatory activity in patients with psoriasis, such as the Psoriasis Area and Severity Index (PASI), are limited.

Objective

To determine whether the Psoriatic Arthritis Screening and Evaluation (PASE) questionnaire can be used to monitor disease activity in patients with psoriasis.

Methods

This was a multicenter, noninterventional, cross-sectional study. Demographic factors and PASI and PASE scores were collected to investigate associations between each.

Results

PASE data were available for 1,255 patients, of whom 498 (39.7%) had a score of ≥37. Compared with the group with PASE score <37, the group with score ≥37 had a higher proportion of women (34.9% vs. 48.8%, p<0.0001), older mean age at diagnosis (36.4 vs. 41.7 years, p<0.0001), more severe disease activity using PASI and body surface area measures (p=0.0021 and p=0.0008, respectively), and higher mean body mass index (23.7 vs. 24.1, p=0.0411). In a multiple linear regression model, PASE score was positively associated with cutaneous disease activity (p<0.0001).

Conclusion

After risk-adjustment, PASE was positively associated with PASI, which suggests that PASE can be sensitive to disease activity. Since psoriasis is regarded as one of the IMIDs, PASE may be utilized as a tool not only to screen PsA but also to monitor disease activity.

Safety evaluation of zinc methionine in laying hens: Effects on laying performance, clinical blood parameters, organ development, and histopathology

The study was conducted to investigate whether high-dose zinc methionine (Zn-Met) affected the safety of laying hens, including laying performance, hematological parameters, serum chemical parameters, organ index, and histopathology. A total of 540 20-week-old Hy-Line White laying hens was randomly allocated to 6 groups with 6 replicates of 15 birds each. Birds were fed diets supplemented with 0 (control), 70, 140, 350, 700, or 1,400 mg Zn/kg diet as Zn-Met. The experiment lasted for 8 wk after a 2-week acclimation period. Results showed that dietary supplementation with 70 or 140 mg Zn/kg diet as Zn-Met significantly increased average daily egg mass (ADEM), laying rate (LR), and feed conversion ratio (FCR) (P < 0.05) and lowered broken and soft-shelled egg ratio (BSER) (P < 0.05) in comparison with the control group; no significant differences were detected among hens fed with 0, 350, or 700 mg Zn/kg as Zn-Met (P > 0.05); hens administered 1,400 mg Zn/kg showed a significant increase in BSER and remarkable decreases in ADEM, LR, and FCR (P < 0.001). There were no significant differences among hens receiving 0, 70, 140, 350, or 700 mg Zn/kg as Zn-Met in serum chemical parameters (P > 0.05); supplementation with 1,400 mg Zn/kg as Zn-Met remarkably elevated the concentrations of serum total bilirubin (TBILI), glucose (GLU), uric acid (UA), and creatinine (CRE) (P < 0.001), and enhanced activities of serum glutamic oxalacetic transaminase (GOP) and alkaline phosphatase (AKP) (P < 0.001) compared with the control group. No significant histopathological changes were found in hens administered 0, 70, 140, 350, or 700 mg Zn/kg as Zn-Met, while significant histological lesions were observed in the heart, liver, lung, and kidney tissues of hens receiving 1,400 mg Zn/kg as Zn-Met. No significant differences were detected in hematological parameters or organ index (P > 0.05). In conclusion, a nominal Zn concentration of 700 mg/kg as Zn-Met is considered to be no-observed-adverse-effect level following daily administration to hens for 56 days.

Baseline extent of damage predicts spinal radiographic progression in Korean patients with ankylosing spondylitis treated with golimumab

BACKGROUND/AIMS

For patients with ankylosing spondylitis (AS), golimumab has consistent efficacy in controlling disease activity over 5 years but its benefit in preventing radiographic progression was less clear at 4 years. To predict radiographic progression, we analyzed the baseline characteristics of AS patients in a Korean population.

METHODS

Sixty-eight Korean patients with AS participated in the phase 3, multicenter, randomized, placebo-controlled, double-blind trial (GO-RAISE) which has previously been described. Baseline modified stoke AS spine score (mSASSS) and change in mSASSS from baseline (ΔmSASSS) until week 208 were analyzed in the Korean patients enrolled in the GO-RAISE study.

RESULTS

Although Korean patients had lower baseline mSASSS compared to non-Korean patients and received active management, radiographic progression was not prevented. Korean patients who did not undergo radiographic progression of spinal lesions of AS were younger and had shorter symptomatic duration, lower Bath AS functional and metrology indices, better chest expansion, and lower baseline mSASSS. The baseline mSASSS and ΔmSASSS were positively correlated in Korean AS patients (p < 0.001). Radiographic progression was more prevalent (80.0%) when baseline mSASSS > 10 and less common (13.0%) with baseline mSASSS = 0.

CONCLUSIONS

In Korean AS patients, radiographic progression of the spine after 4 years was predicted effectively by the initial severity of the spinal lesion(s) in patients treated with golimumab.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study)

BACKGROUND

Psychological aspect and quality of life should be considered in treating patients with psoriasis.

OBJECTIVE

We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis.

METHODS

The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ).

RESULTS

Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental).

CONCLUSION

The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

Antibiotic inclusion in the diet did not alter the standardized ileal digestible tryptophan to lysine ratio for growing pigs

Two 21-d experiments were conducted to determine the optimum standardized ileal digestible (SID) Trp:Lys ratio for growing pigs; 1 experiment fed diets supplemented with or without an antibiotic. The primary response variables in both experiments were ADG, ADFI, G:F, and plasma urea N (PUN) concentrations with the optimum SID Trp:Lys ratio detected using broken-line analysis. Experiment 1 evaluated the optimum SID Trp:Lys ratio in growing pigs fed diets supplemented with an antibiotic. This experiment used 120 crossbred pigs that were blocked by sex and initial BW (24.13 ± 2.72 kg) and allotted to 6 SID Trp:Lys ratios in 4 replicates. Dietary treatments were formulated by the addition of crystalline Trp to create 6 SID Trp:Lys ratios (13.08%, 14.06%, 15.04%, 17.00%, 18.95%, and 20.91%) with a constant SID Lys level of 0.655%. As SID Trp:Lys ratios increased, ADG, ADFI, and G:F increased, and PUN concentrations decreased linearly ( < 0.05) and quadratically ( < 0.05). Linear broken-line analysis yielded optimum SID Trp:Lys ratios of 17.93% ( < 0.001) and 16.17% ( = 0.009) for ADG and PUN, respectively, resulting in a mean optimum SID Trp:Lys ratio of 17.05%. Experiment 2 evaluated the optimum SID Trp:Lys ratio in growing pigs fed diets supplemented with or without an antibiotic. It used a total of 324 crossbred pigs (initial BW: 30.81 ± 3.56 kg) that were allotted to 6 SID Trp:Lys ratios in 6 replicates. Dietary treatments were formulated by the addition of crystalline Trp to create 6 SID Trp:Lys ratios (12.52%, 14.86%, 17.20%, 19.54%, 21.88%, and 24.22%) with a constant SID Lys level of 0.67%. As SID Trp:Lys ratios increased, ADG, ADFI, and G:F increased, and PUN concentrations decreased linearly ( < 0.001) and quadratically ( < 0.001) regardless of antibiotic inclusion. There were no differences by the antibiotic treatment in ADG, ADFI, G:F, or PUN concentrations ( > 0.49) and no interactions between antibiotics and Trp:Lys ratios ( > 0.29). When the data for all pigs were pooled for the various Trp:Lys ratios, the optimum SID Trp:Lys ratios for ADG and PUN based on linear broken-line analysis were 14.58% ( < 0.001) and 14.54% ( < 0.001), respectively, resulting in an optimum SID Trp:Lys ratio of 14.56% as the mean of the determined optima for ADG and PUN responses. These results demonstrate that the optimum SID Trp:Lys ratio for 30- to 50-kg growing pigs is not impacted by the dietary inclusion of an antibiotic as long as the diets are formulated on an SID AA basis.

The Clinical Profile of Patients with Psoriasis in Korea: A Nationwide Cross-Sectional Study (EPI-PSODE)

Background

Psoriasis is an immune-mediated, chronic inflammatory disease affecting multiple aspects of patients' lives. Its epidemiology varies regionally; however, nationwide epidemiologic data on psoriasis depicting profile of Korean patients has not been available to date.

Objective

To understand nationwide epidemiologic characteristics and clinical features of adult patients with psoriasis visited university hospitals in Korea.

Methods

This multicenter, non-interventional, cross-sectional study recruited 1,278 adult patients with psoriasis across 25 centers in Korea in 2013. Various clinical data including PASI, BSA, DLQI, SF-36 and PASE were collected.

Results

A total of 1,260 patients completed the study (male:female=1.47:1). The mean age was 47.0 years with a distribution mostly in the 50s (24.9%). Early onset (<40 years) of psoriasis accounted for 53.9% of patients. The mean disease duration was 109.2 months; mean body mass index was 23.9 kg/m²; and 12.7% of patients had a family history of psoriasis. Plaque and guttate types of psoriasis accounted for 85.8% and 8.4%, respectively. Patients with PASI ≥10 accounted for 24.9%; patients with body surface area ≥10 were 45.9%. Patients with DLQI ≥6 accounted for 78.8%. Between PASI <10 and PASI ≥10 groups, significant difference was noted in age at diagnosis, disease duration, blood pressure, waist circumference of female, and treatment experiences with phototherapy, systemic agents, and biologics.

Conclusion

This was the first nationwide epidemiologic study of patients with psoriasis in Korea and provides an overview of the epidemiologic characteristics and clinical profiles of this patient population.

Clinical factors predicting the therapeutic response to ustekinumab in patients with moderate to severe chronic plaque psoriasis

While ustekinumab has been widely used as an effective biologic for the treatment of chronic plaque psoriasis, no prospective studies have specifically investigated the clinical factors that may influence treatment outcomes with ustekinumab. This post-hoc analysis aimed to identify specific clinical factors that may influence treatment outcomes with ustekinumab in psoriasis patients. In the MARCOPOLO study, 102 Korean patients with moderate to severe psoriasis were analyzed to assess the influence of baseline characteristics as clinical factors on clinical response (improvement in Psoriasis Area and Severity Index by ≥75%/90% [PASI75/PASI90]) to ustekinumab. In addition, differences in PASI75 and PASI90 responses between the responder group and non-responders were evaluated at weeks 28 and 52. Multiple logistic regression analysis was used to determine adjusted clinical factors predicting treatment outcomes among patient characteristics. At week 28, there was a significant difference in PASI75/PASI90 response based on prior biologic experience, although the difference did not persist at week 52. In addition, after adjusting for the effects of relevant clinical factors, biologic experience was significantly associated with less PASI75 (odds ratio [OR] = 0.14, P = 0.001) and PASI90 (OR = 0.22, P = 0.036) responses at week 28. The presence of comorbidities was higher among non-responders than among PASI75/PASI90 responders at both weeks 28 and 52, but was not statistically significant. Previous biologic use was the only clinical factor predicting less response at week 28, although it did not influence the clinical response after week 52. Further studies are warranted to investigate the association between presence of comorbidities and clinical response.

Maternal dietary linoleic acid supplementation promotes muscle fibre type transformation in suckling piglets

As meat quality is basically dependent on muscle fibre characteristics, it is important to know how muscle fibres are regulated and transformed. This study aimed to investigate the effect of maternal dietary supplementation on muscle fibre types using 3% saturated fatty acid (palmitic acid, PA) or 3% unsaturated fatty acid (linoleic acid, LA) from 80 days of gestation to the weaning of offspring (25 days post-natal). The results indicated that higher mRNA levels of MyHCI type genes were found in the soleus muscles of piglets that suckled from LA-supplemented sows than from PA-supplemented sows. In addition, LA treatment increased the gene expression of the type I muscle fibre marker troponin I (p < 0.01), suggesting that LA promoted muscle fibre type transformation to type I fibres. Moreover, PGC-1α (p < 0.01) and MEF2c (p < 0.05) mRNA levels were higher in the piglets from the LA treatment group than in those from the PA treatment group. Furthermore, LA supplementation also significantly increased AMP-activated protein kinase (AMPK) mRNA levels (p < 0.05), which is an upstream regulator of PGC-1α. Collectively, these findings demonstrated that maternal dietary LA supplementation promoted muscle fibre transformation to type I fibre and that this process may be mediated through an AMPK-dependent pathway.

Effect of ultrasonic waves on the freezing rates of potatoes in degassed coolant and untreated coolant

BACKGROUND

Ultrasonic waves are shown to enhance the rate of freezing.

OBJECTIVE

To elucidate the mechanism of immersion freezing of potatos with ultrasonic waves.

MATERIALS AND METHODS

Ultrasound is applied to potato samples immersed in degassed coolant and untreated coolant. Sonic waves were intermittently applied at temperature below -1 degree C. The freezing rates were measured under different experimental conditions.

RESULTS

The use of ultrasonic waves increased the freezing rates of potatoes immersed in both degassed coolant and untreated coolant. However, the freezing rate in the degassed coolant was less than that in the untreated coolant.

CONCLUSION

Heat transfer on the interface between the potato sample and sonicated degassed coolant appears to be less than that within the sample in the absence of cavitation. The interface heat transfer between the potato sample and untreated coolant is likely improved due to ultrasonic cavitation.

Influence of dietary inclusion of Bacillus licheniformis on laying performance, egg quality, antioxidant enzyme activities, and intestinal barrier function of laying hens

This experiment was conducted to evaluate the effects of dietary inclusion of Bacillus licheniformis on laying performance, egg quality, antioxidant enzyme activities, and intestinal barrier function of laying hens. Hy-Line Variety W-36 hens (n = 540; 28 wk of age) were randomized into 6 groups, each group with 6 replications (n = 15). The control group received the basal diet formulated with maize and soybean meal. The treatment groups received the same basal diets supplemented with 0.01, 0.02, 0.03, 0.06, and 0.09% Bacillus licheniformis powder (2 × 10(10) cfu/g) for an 8-wk trial. The results showed that dietary supplementation with 0.01 and 0.03% B. licheniformis significantly increased egg production and egg mass. However, no significant differences were observed in egg weight, feed consumption, and feed conversion efficiency among the 6 groups. Supplementation with different levels of B. licheniformis was found to be effective in improvement of egg quality by increasing egg shell thickness and strength. Compared with control, d-lactate content, diamine oxidase activity, and adrenocorticotropic hormone level in serum decreased significantly, and the level of estradiol and follicle-stimulating hormone increased significantly in plasma of all the experimental groups. Dietary supplementation with B. licheniformis increased the intestinal villus height and reduced the crypt depth. In conclusion, dietary inclusion of B. licheniformis could improve laying performance and egg quality significantly in a dose-dependent manner by decreasing the stress response, upregulating the growth hormone, and improving intestinal health.

Effect of Saccharomyces boulardii and Bacillus subtilis B10 on intestinal ultrastructure modulation and mucosal immunity development mechanism in broiler chickens

The recent ban on the use of antibiotics as a feed additive has led to the search for alternative sources of antibiotics in the feed industry. Presently, probiotics are considered as a potential substitute for antibiotic as a live biotherapeutic agent to improve animal health and performance. Accordingly, study was focused on evaluating the effect of Saccharomyces boulardii (Sb) and Bacillus subtilis B10 (Bs) on ultrastructure modulation and mucosal immunity development in broiler chickens. A total of three hundred 1-d-old Sanhuang broilers (a Chinese cross breed) were randomized into 3 groups, each group with 5 replications (n = 20). The control group (Ctr) was fed a basal diet containing an antibiotic (virginiamycin, 20 mg/kg). Meanwhile, broilers in experimental groups received Sb and Bs (1 × 10(8) cfu/kg of feed) in addition to the basal diet for 72 d. The results of the experimental groups revealed a significant improvement in live BW and relative weight of bursa of Fabricius and thymus. Also, intestinal villus height, width, and number of goblet cells increased in the Sb and Bs groups. Meanwhile, modulation in the intestinal ultrastructure and increased mRNA expression levels of occluding, cloudin2, and cloudin3 (P < 0.05) were observed in the Sb and Bs groups. Moreover, IgA-positive cells significantly increased in the jejunum of Sb- and Bs-supplemented groups (P < 0.05). Intestinal cytokines interleukin-6, tumor necrosis factor-α, interleukin-10, transforming growth factor-β, and secretory IgA concentrations were (P < 0.05) improved in the probiotic groups; however, Sb induced inflammatory and antiinflammatory cytokines (P < 0.05) in comparison with the Ctr group. The present findings conclusively revealed that Sb and Bs increased IgA-positive cells in the lumen of the intestinal villus and revealed that Sb and Bs could modulate intestinal ultrastructure through increasing occluding, cloudin2, and cloudin3 mRNA expression levels in broiler intestine.

Assessment of Cu (II)-bearing montmorillonite on Cd adsorption

The abilities of montmorillonite (MMT) and Cu (II)-bearing montmorillonite (Cu-MMT) for adsorption of Cd from aqueous solutions have been studied at different optimized conditions of shaking time, pH value, and initial concentration, respectively. The results showed that the adsorbability of Cu-MMT onto Cd is stronger than the MMT. The amount of Cu-MMT necessary to remove Cd from solution was about 0.5 g for 100-200 mg/L Cd solution at a pH of 4.0. The maximum adsorption (94%) was 20 min of shaking time using Cu-MMT as adsorbent. The maximum adsorption of Cd = 95% at a pH of 4.0. By increasing the initial concentration, the adsorption amount of Cd onto Cu-MMT increased. Animal experiment of this study indicated that the addition of Cu-MMT to the Cd-contaminated diet of pigs reduced significantly the Cd levels in tissues (p < 0.05) and increased contents in feces (p < 0.01), improving the safety of animal products. Thus, the overall results established the use of Cu-MMT as a heavy metal adsorbent in animal's diets, implying a potential protective role against heavy metal toxicities.

Effect of montmorillonite superfine composite on growth performance and tissue lead level in pigs

A feeding trial was conducted to study the effect of montmorillonite superfine composite (MSC) on growth performance and tissue lead levels in pigs. Sixty barrows were randomly divided into two groups. They were fed the same basal diet supplemented with 0 or 0.5% MSC, respectively, for 100 days. Serum samples were collected and analyzed to study growth hormone secretion pattern. The mean lead concentration in selected tissues was analyzed. The results showed that average daily gain, average daily feed intake, and feed conversion ratio of pigs were improved by 8.97% (p < 0.05), 3.90% (p < 0.05), and 4.76% (p < 0.05), respectively, with the supplementation of MSC compared to the control group. Serum sample analysis indicated that peak amplitude, base-line level, and mean level of growth hormone were increased by 117.14% (p < 0.01), 42.78% (p < 0.01), and 51.75% (p < 0.01), respectively. Supplementation of MSC in the diet was found to significantly reduce lead concentration of tissues in blood, brain, liver, bone, kidney and hair.

[Not Available]

The aim of the study was to determine whether the Heidelberg Retinal Flowmeter (HRF), a confocal scanning laser Doppler flowmeter, can measure choroidal blood flow in pig eyes.

An HRF was used to obtain flow maps from in vitro pig eyes under a range of perfusion flow rates (0 – 500 µL/min) under conditions in which only the choroid was perfused. In some cases choroidal blood flow was also measured simultaneously using a conventional fiberoptic based Laser Doppler Perfusion Monitor (LDPM) which used the same laser wavelength (780 nm). The relationship between perfusion flow, HRF measured flow and LDPM measured flow was determined. HRF flow maps were also obtained in vivo as a function of focal plane setting through the retina and choroid.

Across the range of perfusion flow rates through the isolated eyes there was a poor correlation with HRF measured choroidal flow and perfusion flow. In contrast, there was a strong linear relationship between perfusion flow and LDPM measured blood flow. Both in vitro and in vivo, no choroidal vessels could be visualised in the HRF flow maps, even when the focal plane was in the choroid.

The HRF is unable to measure choroidal blood flow in pig eyes. This is not due to an inability of the 780 nm laser to penetrate into the choroid or due to red blood cell velocities in the choroid being higher than the measurement range of the instrument.

Effects of lead on hepatic antioxidant status and transcription of superoxide dismutase gene in pigs

Ninety-six castrated boars (Duroc x Landrace x Yorkshire) were randomly divided into four groups, each of which was replicated three times with eight pigs. The groups received the same basal diet supplemented with 0, 5, 10, and 20 mg/kg lead, respectively. The malondialdehyde and glutathione levels, antioxidant enzymes activities, and zinc/copper superoxide dismutase (Zn/Cu SOD) mRNA content in the liver were determined to evaluate the lead hepatic intoxication caused by the lead. Results showed the increased lipid peroxides level and the reduced glutathione content, along with a concomitant decrease in the activities of superoxide dismutase, catalase, and glutathione peroxidase. Moreover, the level of hepatic Zn/Cu SOD mRNA was also significantly reduced. We suggest potential mechanism for lead intoxication in liver as follows: lead causes parallel decrease in Zn/Cu SOD mRNA and activities of antioxidant enzymes, leading to the declined ability of scavenging free radicals with excessive production of lipid peroxides, which seriously damages the hepatic structure and function.

Induction of membrane-type matrix metalloproteinase-1 stimulates angiogenic activities of bovine aortic endothelial cells

Matrix metalloproteinases (MMPs) have been reported to play critical roles in endothelial cell migration and matrix remodeling during the angiogenic process. Among these MMPs, membrane-type MMP-1 (MT1-MMP) is an important molecule that can trigger the invasion of tumor cells by activating MMP-2 on their plasma membrane. However, the precise involvement of MT1-MMP in the angiogenic process has not been determined. To investigate the roles of the MT1-MMP by the matrix remodeling of endothelial cells, MT1-MMP expression vector was transfected into bovine aortic endothelial cells (BAECs). Increased expression of MT1-MMP in BAECs enhanced the activation of MMP-2, invasion and migration of BAECs. Moreover, the capacity of tube formation was increased in MT1-MMP transfectants. However, cotransfection with antisense MT1-MMP expression vector abolished the effects of MT1-MMP overexpression. These observations indicate that MT1-MMP is involved in the angiogenic process of endothelial cells in vitro.

An in vivo and in vitro comparison of the effects of vasoactive mediators on pulpal blood vessels in rat incisors

The effects of endogenous vasoactive substances were evaluated in anaesthetized rats using a laser Doppler flowmeter to monitor changes in pulpal blood flow, as well as directly in isolated pulpal arteriole preparations utilising a microperfusion and monitoring system to observe changes in vessel diameter. In anaesthetized rats, while systemic arterial blood pressure remained relatively stable, intra-arterial delivery of adrenaline (epinephrine) (A), noradrenaline (norepinephrine) (NA), phenylephrine (PHE), dopamine (DOPA), 5-hydroxytryptamine (5-HT), or endothelin-1 (ET-1) produced a dose-dependent reduction in pulpal blood flow (order of potency: ET-1>>A=NA>PHE=DOPA=5-HT); acetylcholine induced a dose-dependent increase in pulpal blood flow; histamine, isoproterenol and adenosine produced no significant changes. In isolated arteriole preparations, intraluminal delivery of A, NA, PHE, DOPA or 5-HT produced dose-dependent vasoconstriction (A=NA>PHE=DOPA=5-HT). Acetylcholine relaxed NA-precontracted vessels dose-dependently. Histamine and isoproterenol produced a small vasodilatation. Intraluminal ET-1 produced a small vasoconstriction at 10(-8)M, whereas extraluminal ET-1 produced a dose-dependent vasoconstriction from 10(-10)M and above. Intraluminal adenosine failed to dilate vessels precontracted with ET-1, whereas extraluminal adenosine caused a complete relaxation. These combined in vivo and in vitro data suggest that, in the rat incisor, the pulpal microcirculation is capable of functional regulation and that pulpal blood flow may be modulated by endothelium-related factors, metabolic (tissue-related) factors, as well as humoral (blood-borne) factors.

Oxygen distribution and consumption in rat lower incisor pulp

The aim was to determine the oxygen tension (P(O(2))) and rate of oxygen consumption in the pulp. Twelve rats were anaesthetised and artificially ventilated. Under an operating microscope, a recessed oxygen-sensitive microelectrode was inserted into the pulp through a small saline-covered cavity on the labial surface of the lower incisor. P(O(2)) was measured as a function of the transverse distance from the saline medium through to the middle of the pulp. Oxygen profiles were characterised by a decline of oxygen tension outside the pulp in the saline medium and a steeper gradient across the interface, before a localised oxygen consuming region corresponding to the odontoblasts. A plateau with some localised fluctuations was then followed by an increase in oxygen tension in the middle of the pulp. The average oxygen tension in the plateau region was 23.2 mmHg+/-2.1 mmHg (n=12). A mathematical model was used to extract oxygen consumption data from P(O(2)) profiles recorded from non-perfused pulp (created by reducing systemic blood pressure). The analysis revealed that there was a distinct oxygen consumption zone in the outer pulp, which anatomically corresponded to the odontoblast layer. The average oxygen consumption rate of the odontoblasts was 3.2+/-0.2 ml O(2)/min per 100g pulp tissue. The zone of high oxygen consumption was 68.7 micro m+/-6.9 micro m (n=24) thick. It is concluded that pulpal oxygen distribution is heterogeneous and that the odontoblast could be a major oxygen consumer within the rat incisor pulp.

Agonist-induced vasoactive responses in isolated perfused porcine dental pulpal arterioles

A novel isolated perfused pulpal arteriole preparation and microperfusion system was used to evaluate the direct vasoactive responses of pulpal arterioles to selected agonists. Short lengths of porcine pulpal arterioles (101.7+/-2.2 microm o.d., n=105) were dissected out and placed in an environment-controlled bath on the stage of an inverted microscope. Both ends of the vessel were cannulated and perfused at a controlled rate through the lumen. The diameter of the vessel was measured online. Following equilibration, the vessel was challenged with various agonists: adrenaline (epinephrine), noradrenaline (norepinephrine), phenylephrine, dopamine, isoproterenol, 5-hydroxytryptamine, histamine and adenosine. The endothelium-dependent vasodilator acetylcholine was used to evaluate endothelial cell function. Adrenaline, noradrenaline, phenylephrine, 5-hydroxytryptamine and dopamine caused dose-dependent contractions (adrenaline=noradrenaline>phenylephrine>dopamine>5-hydroxytryptamine). Isoproterenol and histamine provoked a dose-dependent dilation. Adenosine produced pronounced vasodilatation in vessels precontracted with 10(-8)M endothelin-1. Functional adrenergic, histamine, 5-hydroxytryptamine and adenosine receptors are, therefore, present in porcine pulpal arterioles. The isolated perfused pulpal arteriole preparation may prove valuable in understanding local control mechanisms of pulpal microcirculation.

Acetylcholine-induced vasodilation of isolated pulpal arterioles

The presence of cholinergic mechanisms in the control of pulpal microcirculation has been a controversial issue. In this study, we aimed to determine the direct vasoactive responses of isolated pulpal arterioles to acetylcholine, and to investigate whether such responses are endothelium-dependent. Using an in vitro micro-perfusion system, we isolated pig pulpal arterioles, cannulated and perfused them intraluminally, and monitored the diameter. Following equilibration, the vessels were contracted with 10(-5) M noradrenaline, and the effect of increasing doses of acetylcholine was determined. The influence of the muscarinic antagonist, atropine, or the loss of endothelial cell function following saponin treatment was also determined. Acetylcholine induced a dose-dependent vasodilation, reaching 94.6+/-1.4% (n = 22) of the uncontracted diameter at 10(-4) M. The vascular relaxation effect of acetylcholine was abolished in the presence of atropine, and by saponin treatment. Analysis of these data suggests that, in the pig, the acetylcholine-induced vasodilation of incisor pulpal arterioles is endothelium-dependent and mediated by muscarinic receptors.

Methimazole as an antioxidant and immunomodulator in thyroid cells: mechanisms involving interferon-gamma signaling and H(2)O(2) scavenging

The antithyroid drug, methimazole (MMI) is used to treat patients with Graves' hyperthyroidism. The major action of MMI is to inhibit synthesis of thyroid hormone in the thyroid gland. However, MMI also has antioxidant and immunomodulatory effects on thyrocytes and/or immune cells. This study identifies novel antioxidant and immunomodulatory effects of MMI involving the interferon-gamma (IFN-gamma) signaling pathway in thyroid cells. MMI inhibits transcription of the intercellular adhesion molecule-1 (ICAM-1) gene by modulating the function of transcription factor STAT1 (signal transducer and activator of transcription 1), which binds to the IFN-gamma activated site of the ICAM-1 promoter. Furthermore, MMI rapidly eliminates H(2)O(2) produced by IFN-gamma treatment in thyroid cells and thus inhibits the H(2)O(2)-mediated phosphorylation of tyrosine 701 in STAT1. MMI also eliminates H(2)O(2) in vitro. MMI facilitates electron transfer from NADPH to H(2)O(2) using thioredoxin or glutathione, fulfilling a role similar to peroxiredoxin or glutathione peroxidase, respectively. MMI prevents the IFN-gamma and H(2)O(2)-mediated reversible inactivation of phosphatases. These effects inhibit full activation of the IFN-gamma-induced Janus kinase(JAK)/STAT signaling pathway in FRTL-5 thyroid cells. These results may in part explain the antioxidant and immunomodulatory effects of MMI in thyroid cells of Graves' disease patients.

Weekly dosing of carboplatin increases risk of allergy in children

BACKGROUND

Carboplatin (CBDCA) has been used increasingly to treat pediatric low-grade gliomas. Allergic reactions to CBDCA have been reported in 2% to 30% of children. The reason for this high incidence of allergy is unclear.

METHODS

To determine the risk factors for CBDCA allergy, an historic cohort study was conducted for all children who received the drug during a 6-year period at the Lucile Salter Packard Children's Hospital at Stanford. The patients' medical records were reviewed for data on age, tumor type, CBDCA dose schedule, total number of doses, cumulative dosage, dose per treatment, other chemotherapy administered, and allergic reaction.

RESULTS

Fifty-four children (mean age 7.2 years, 35 boys) were identified. Six children (11.1%) had an allergic reaction to CBDCA. All reactors had low-grade gliomas treated with weekly CBDCA and vincristine, with a dosage per treatment <500 mg/m2. Overall, six (75%) of eight children administered weekly CBDCA, 6 (46.2%) of 13 children with brain tumors, and 6 (40%) of 15 administered CBDCA dosage <500 mg/m2 manifested allergic reactions. Patients receiving more than five doses had significant risk for CBDCA allergy (relative risk [RR] = 11.8; 95% confidence interval [CI]: 1.5-94.1). Using logistic regression with multiple variables, weekly dose schedule was the most predictive covariate for allergic reaction (P < 0.000 1), and other factors were unrelated or redundant.

CONCLUSIONS

Children with low-grade gliomas receiving CBDCA weekly are at significantly increased risk for CBDCA allergy. The repetitive, weekly dosing schedule of CBDCA appears to be a key risk factor for allergic reaction in brain tumor patients. The high frequency of allergy with weekly CBDCA warrants further consideration when planning future trials.

Comparison of the vasoactive effects of the docosanoid unoprostone and selected prostanoids on isolated perfused retinal arterioles

PURPOSE

To compare the vasoactive properties of the docosanoid unoprostone, its free acid, and different members of the prostanoid family on isolated perfused pig retinal arterioles to assess their potential to modulate retinal blood flow.

METHODS

Segments of porcine retinal arterioles were dissected, cannulated, and perfused, and their diameter monitored during either intraluminal or extraluminal application of increasing doses (10(-10)-10(-4) M) of either the docosanoid unoprostone isopropyl and its free acid or of selected prostanoids: prostaglandin (PG) F(2alpha) and thromboxane A(2) analogue (U46619). Studies were performed on arterioles in their uncontracted state, and also during precontraction with endothelin-1 (10(-9) M). The significance of any induced change in vessel diameter was assessed in relation to the initial vessel diameter or, in the case of endothelin-1 administration, to the contracted diameter with endothelin-1 alone.

RESULTS

In normal-tone arterioles without endothelin-1 contraction, PGF(2alpha) and U46619 both produced a potent dose-dependent contraction, but neither unoprostone isopropyl nor unoprostone free acid had a significant vasoactive effect. In endothelin-1-contracted arterioles, U46619 produced further contraction, PGF(2alpha) produced a slight vasodilatation, and unoprostone isopropyl and its free acid produced a pronounced dilatation.

CONCLUSIONS

Of the agents tested, unoprostone isopropyl and its free acid were the most potent vasodilators of endothelin-1-contracted pig retinal arterioles. Members of the prostanoid family demonstrated a different effect on the diameter of isolated retinal arterioles compared with the docosanoids. The potential therefore exists for the docosanoid unoprostone to have a beneficial effect on retinal blood flow in addition to any reduction in intraocular pressure.

Pathogenesis and intervention strategies in diabetic retinopathy

Diabetic retinopathy is the leading cause of new blindness in the working-age population. If improved treatment regimens are to be developed it is crucial that the underlying pathophysiological mechanisms responsible for diabetic retinopathy are better understood. The multifactorial nature of the many pathways implicated in diabetic retinopathy requires a very detailed approach to elucidate the key mechanisms involved and their interactions in order to develop logical strategies aimed at therapeutic intervention. Fortunately, the streptozotocin rat model of diabetes displays many of the morphological and functional changes to the retinal vasculature that are evident in human diabetic retinopathy. This study reviews some of the recent experimental work by the authors in the streptozotocin rat, compares their findings to the human pathology and outlines potential new avenues for therapeutic intervention. In particular the improved understanding of which layers of the inner retina have the most stringent metabolic demands has helped identify which retinal layers are most susceptible to metabolic or hypoxic/ischaemic insult. It is concluded that improved treatment outcomes may ensue if the therapy is targeted at the appropriate tissue at specific stages of the disease.

A pilot study of in vivo venous pressures in the pig retinal circulation

Retinal venous pressure was examined in six pigs using a balanced servo-nulling micropuncture technique. The mean transmural venous pressure was 0.95 mmHg (SD 1.50 mmHg). The transmural venous pressure was lower at the optic disc than away from the disc (0.32 +/- 1.46 mmHg vs 1.69 +/- 1.19 mmHg, P < 0.01). At the disc a transmural pressure of zero or less (0 to -0.5 mmHg) was demonstrated in 10/21 (48%) of the disc readings. Over an intraocular pressure range of 15-26 mmHg there was a strong correlation between intraocular pressure and retinal venous pressure (Pearson coefficient r = 0.92). The results are compatible with the Starling resistor theory of venous outflow from the eye.

Tetrahydrobiopterin reverses the impairment of acetylcholine-induced vasodilatation in diabetic ocular microvasculature

The purpose of this study is to test whether tetrahydrobiopterin, an essential cofactor in nitric oxide synthesis, can reverse endothelium dysfunction in diabetic ocular circulation. Using the streptozotocin-induced diabetic rat model and the isolated perfusion eye technique, the response to the acetylcholine (an endothelium-dependent vasodilator mediated by stimulated nitric oxide release) induced vasodilatation of the diabetic ocular vasculature before and after tetrahydrobiopterin administration was compared. Age matched normal rats were used for reference response. Six streptozotocin-induced diabetic rats and eleven control rats at 21.5 +/- 0.2 weeks and 21.2 +/- 2.1 weeks postinduction, respectively, were used. The dose response curve from the diabetic eyes was found to be significantly different from that of the control eyes (p < 0.001) with significantly reduced responses to 10(-4)M acetylcholine. After 30 min of administration of tetrahydrobiopterin to the diabetic eyes, however, the acetylcholine-induced vasodilatation response was significantly (p < 0.001) increased compared with the response prior to tetrahydrobiopterin administration. The vasodilatory response in the diabetic eyes after tetrahydrobiopterin administration was at a level that was comparable with the control response (p = 0.742). We have shown that acute administration of tetrahydrobiopterin is effective in reversing to control level the impaired acetylcholine-induced vasodilatory response at 21.5 +/- 0.2 weeks postinduction. Our result suggests that a decreased level of tetrahydrobiopterin in the eyes of the streptozotocin-induced diabetic rats may be responsible for the ocular vascular endothelium dysfunction.

Oxygen distribution and consumption within the retina in vascularised and avascular retinas and in animal models of retinal disease

Maintenance of an adequate oxygen supply to the retina is critical for retinal function. In species with vascularised retinas, such as man, oxygen is delivered to the retina via a combination of the choroidal vascular bed, which lies immediately behind the retina, and the retinal vasculature, which lies within the inner retina. The high-oxygen demands of the retina, and the relatively sparse nature of the retinal vasculature, are thought to contribute to the particular vulnerability of the retina to vascular disease. A large proportion of retinal blindness is associated with diseases having a vascular component, and disrupted oxygen supply to the retina is likely to be a critical factor. Much attention has therefore been directed at determining the intraretinal oxygen environment in healthy and diseased eyes. Measurements of oxygen levels within the retina have largely been restricted to animal studies in which oxygen sensitive microelectrodes can be used to obtain high-resolution measurements of oxygen tension as a function of retinal depth. Such measurements can immediately identify which retinal layers are supplied with oxygen from the different vascular elements. Additionally, in the outer retinal layers, which do not have any intrinsic oxygen sources, the oxygen distribution can be analysed mathematically to quantify the oxygen consumption rate of specific retinal layers. This has revealed a remarkable heterogeneity of oxygen requirements of different components of the outer retina, with the inner segments of the photoreceptors being the dominant oxygen consumers. Since the presence of the retinal vasculature precludes such a simple quantitative analysis of local oxygen consumption within the inner retina, our understanding of the oxygen needs of the inner retinal components is much less complete. Although several lines of evidence suggest that in the more commonly studied species such as cat, pig, and rat, the oxygen demands of the inner retina as a whole is broadly comparable to that of the outer retina, exactly which cell layers within the inner retina have the most stringent oxygen demands is not known. This may be a critical issue if the cell types most at risk from disrupted oxygen supply are to be identified. This paper reviews our current understanding of the oxygen requirements of the inner and outer retina and presents new data and mathematical models which identify three dominant oxygen-consuming layers in the rat retina. These are the inner segments of the photoreceptors, the outer plexiform layer, and the deeper region of the inner plexiform layer. We also address the intriguing question of how the oxygen requirements of the inner retina are met in those species which naturally have a poorly vascularised, or even totally avascular retina. We present measurements of the intraretinal oxygen distribution in two species of laboratory animal possessing such retinas, the rabbit and the guinea pig. The rabbit has a predominantly avascular retina, with only a narrow band of retinal vasculature, and the guinea pig retina is completely avascular. Both these animals demonstrate species adaptations in which the oxygen requirement of their inner retinas are extremely low when compared to that of their outer retinas. This finding both uncovers a remarkable ability of the inner retina in avascular species to function in a low-oxygen environment, and also highlights the dangers of extrapolating findings from avascular retinas to infer metabolic requirements of vascularised retinas. Different species also demonstrate a marked diversity in the manner in which intraretinal oxygen distribution is influenced by increases in systemic oxygen level. In the vascularised rat retina, the inner retinal oxygen increase is muted by a combination of increased oxygen consumption and a reduction of net oxygen delivery from the retinal circulation. The avascular retina of the guinea pig demonstrated a novel and powerful regulatory mechanism that prevents any dramatic rise in choroidal oxygen levels and keeps retinal oxygen levels within the normal physiological range. In contrast, in the avascular regions of the rabbit retina the choroidal oxygen level passively follows the increase in systemic oxygenation, and there is a dramatic rise in oxygen level in all retinal layers. The presence or absence of oxygen-regulating mechanisms may well reflect important survival strategies for the retina which are not yet understood. Intraretinal oxygen measurements in rat models of retinal disease are also presented. We describe how oxygen distribution across the rat retina is influenced by manipulation of systemic blood pressure. We examine the effect of acute and chronic occlusion of the retinal vasculature, and explore the feasibility of meeting the oxygen needs of the ischemic retina from the choroid. (ABSTRACT TRUNCATED)

Overexpression of membrane-type matrix metalloproteinase-1 gene induces mammary gland abnormalities and adenocarcinoma in transgenic mice

To investigate the role of membrane-type matrix metalloproteinase-1 (MT1-MMP) in mammary gland development and tumorigenesis, transgenic mice overexpressing MT1-MMP in mammary gland under the control of the mouse mammary tumor virus long terminal repeat-promoter were generated. The mouse mammary tumor virus/MT1-MMP transgenic mice displayed abnormalities in 82% of female mammary glands. The abnormalities were verified as lymphocytic infiltration, fibrosis, hyperplasia, alveolar structure disruption, dysplasia, and adenocarcinoma. Northern and reverse transcription-PCR analyses demonstrated that MT1-MMP mRNA was overexpressed in mammary glands exhibiting abnormalities. Western blot analysis and immunohistochemical studies have revealed that the protein expression level was also increased in these glands. In addition, the beta-casein gene as a functional epithelial cell marker was poorly expressed in the mammary glands of transgenic mice exhibiting abnormalities. Gelatin zymography showed significantly increased MMP-2 activation in these mammary glands. These results showed that overexpression of MT1-MMP induced remodeling of the extracellular matrix and tumor formation in the mammary glands of transgenic mice. Therefore, we suggest that overexpression of MT1-MMP may play a key role in development and tumorigenesis in mammary glands.

[Microsatellite marker analysis of a soybean recombinant inbred line NJRIKY]

The prerequisite of genomic research such as genetic mapping is construction of a suitable segregating population and its reasonable evaluation before use. A recombinant inbred line (RILs), NJRIKY, was constructed through a cross between Kefeng 1 and Nannong 1138-2. The present study was focused on evaluation of genetic structure of the RILs through the simple sequence repeats (SSRs) analysis. A total number of 138 pairs of SSRs primers covering the whole soybean genome were randomly selected for polymorphic analysis between two parents. 86 pairs of which were polymorphic and polymorphic rate is up to 62.32%. 90 polymorphic loci were found. Further analysis with polymorphic SSRs loci on the sampled lines indicated that not only segregation of most SSRs loci conformed to the ratio of 1:1, but also almost each sampled line tended to homozyge. The distribution of genotypic composition was normal. The population is ideal for genetic mapping and other genomic research.

A novel epigenetic control operating on Vme1+ locus leads to variegated monoallelic expression

Vme1, located near an imprinted region containing Peg1/Mest, Copg2, and Mit1/Lb9 on mouse chromosome 6, was identified and characterized to be under novel epigenetic regulations mediating nonimprinted monoallelic expression. The gene was transcribed independently from at least four promoters and alternatively spliced. Variable expression of the gene was found among individuals and was not affected by genetic backgrounds, in contrast to a relatively consistent expression of unlinked Peg3 under different genetic backgrounds. Monoallelic expression of the gene was confirmed in several tissues of hybrid F1s between a domesticus and a molossinus subspecies. The nature of monoallelic expression was different from those of its neighboring genes with respect to the allelic preference for the expression. The observed variable expression and monoallelic expression propose a mechanism that operates to variegate the Vme1 transcription acting asynchronously on parental alleles. In addition, we observed that some biallelically expressed tissues exhibited allele-specific splicing such that expression from one parental allele yields elongated splice variants, whereas the other allele is spliced into a short version. This unusual finding suggests that an epigenotype of the promoter can determine the splicing fate of the transcript.

Intraretinal oxygen levels before and after photoreceptor loss in the RCS rat

PURPOSE

To measure the intraretinal oxygen environment at different stages in the Royal College of Surgeons (RCS) rat model of retinal degeneration to determine whether changes in oxygen level are an important aspect of the disease.

METHODS

Oxygen-sensitive microelectrodes were used to measure oxygen tension as a function of depth through the retina of anesthetized, mechanically ventilated RCS rats at ages ranging from postnatal day (P)20 to P104. The oxygen profiles were correlated with histologic observations of the cellular changes within the dystrophic retinas and compared with those in RCS-rdy(+) control animals and published values in normal mature rats.

RESULTS

Although the youngest rats studied exhibited some differences in intraretinal oxygen distribution compared with mature animals, the distribution in dystrophic RCS rats at P20 was not significantly different from that in age-matched control subjects. However, the intraretinal oxygen distribution in dystrophic RCS rats was clearly affected after approximately P30, reflecting a loss of photoreceptor oxygen consumption consistent with histologic observations. In contrast, oxygen uptake by the inner retina was still evident long after the loss of photoreceptors was essentially complete.

CONCLUSIONS

There was no significant tissue hypoxia during photoreceptor degeneration in the dystrophic RCS rat. The changes in intraretinal oxygen distribution are consistent with the loss of outer retinal oxygen uptake but the preservation of inner retinal oxygen metabolism.

Blastocyst viability and generation of transgenic cattle following freezing of in vitro produced, DNA-injected embryos

This study examined whether the viability, determined in vitro, of DNA-injected bovine embryos produced in vitro was affected by freezing, and if the frozen embryos developed to term following transfer to recipients. In vitro fertilized zygotes were injected with the pBL1 gene and then co-cultured with mouse embryonic fibroblasts (MEF) in CR1aa medium. Embryos were prepared for cryopreservation by exposure to a 10% (v/v) glycerol solution, loaded into 0.25 ml straws and then frozen by conventional slow freezing. Thawing was by rapid warming in water (37 degrees C) and embryos were rehydrated in PBS diluents of 6%, 3% and 0% (v/v) glycerol supplemented with 0.25 M sucrose and 0.5% (w/v) BSA. In Experiment 1, blastocysts that developed from DNA-injected embryos were individually classified into three morphological groups and three stages of development prior to freezing. DNA-injected blastocysts of excellent quality at freezing showed a higher survival rate (78.8+/-10.6%) after thawing than those of good (60. 9+/-16.4%) or fair (12.5+/-5.9%) quality (P<0.05). Post-thaw survival rate, judged in vitro, increased with more advanced stage of blastocyst development at freezing (early 48.8+/-15.9%, mid 52. 1+/-12.6% and expanded 71.2+/-1.1; P<0.05). In Experiment 2, the frozen/thawed embryos were transferred to recipients to examine in vivo viability. Following transfer of one or two embryos per recipient, pregnancy rates at 60 days of gestation were 13.6% (13/96) for frozen embryos and 26.5% (43/162) for fresh embryos (P<0. 05). Of the 12 live calves born from the frozen/thawed embryos, two males (18.3%) were transgenic. None of the live-born calves derived from fresh embryos exhibited the transgene. One of transgenic bulls did not produce transgenic sperm. Three out of 23 calves (13.0%) produced from cows inseminated with semen of the other bull were transgenic, suggesting that this animal was a germ-line mosaic. These studies indicated that the viability of in vitro produced, DNA-injected bovine blastocysts was affected by freezing and by both the quality and stage of development of the embryo prior to freezing. The generation of transgenic cattle demonstrates that it is feasible to freeze DNA-injected, in vitro produced embryos.

Acetylcholine-induced relaxation in rat ocular vasculature

Endothelial cell function is often evaluated by the assessment ofendothelium-dependent relaxation to acetylcholine. The purpose of this study was to characterize the acetylcholine-induced vasodilator responses in the intact ocular vasculature tree in isolated perfused rat eyes. At a fixed perfusion flow rate (5 microl/min), the resultant perfusion pressure reflected the total vascular resistance of the perfused vasculature. The baseline vascular resistance, and hence perfusion pressure, was manipulated by perfusion with high concentrations of potassium Krebs (60, 90, or 124 mM). The response to bolus administration of acetylcholine (10(-8) to 10(-4) M) was then assessed over a range of perfusion pressures. Acetylcholine induced a dose-dependent relaxation response which was larger in magnitude with increased levels of induced vascular tone. The relationship between the size of the acetylcholine-induced response and the baseline perfusion pressure was essentially linear with a correlation coefficient of 0.86 at 10(-5) M and of 0.88 at 10(-4) M acetylcholine. Our results suggest that, in the isolated perfused rat eye, the initial vascular tone has to be considered when evaluating endothelial cell function by acetylcholine-induced relaxation.

Molecular cloning and characterization of the mouse peroxiredoxin V gene

We have cloned two cDNA isoforms as well as genomic sequences of the mouse Prx V gene and characterized their molecular genetic features. Two isoforms of the mouse Prx V cDNA were identified from liver and testis. The testis-originated long transcripts had extra 1164-bp 5'-UTR sequences compared to the liver-originated short transcripts. Primer extension and sequence analyses revealed that the two isoforms were presumably transcribed at the same gene locus. The gene was composed of six exons spanning 3.2 kb. The short transcript was abundantly expressed in the kidney, liver, and heart of the adult mouse tissues and in the extra-membrane of the 10.5 dpc embryos. The long transcript of 1985 bp was abundantly detected in testis with trace amounts in other tissues. Interestingly, in testis and fetus, only mRNA expression of the long form was identified. However, the protein expression was not found in testis, implying that the long form could not properly direct the protein expression. The long Prx V cDNA has eight uORFs in the extra 5'-UTR, which proceed the major ORF. The inability of protein expression for the long-form cDNA in testis suggests that the uORFs might inhibit translation of the major ORF and thereby confer the tissue-specific regulation of the mouse Prx V gene.

Antimicrobial peptide of korean native goat lactoferrin and identification of the part essential for this activity

The antimicrobial activity of lactoferrin isolated from Korean native goat (KN goat) milk was studied and its antimicrobial domain was identified using synthetic peptides. Antimicrobial activity was assayed by a micro-method using 96-well microplates and a microplate reader. The amino acid sequence of the antimicrobial domain was suggested to be YQWQRRMRKLGAPSIT and this sequence corresponds to amino acid residues 20 to 35 of KN goat lactoferrin. Five peptides with certain amino acid residues deleted were synthesized in an effort to identify the residues essential for antimicrobial activity and it was found that the part with the sequence RRMRK (24-28) is the region most important for this activity. On the other hand, the conformation of the peptides did not influence the antimicrobial activity.

Continued progression of retinopathy despite spontaneous recovery to normoglycemia in a long-term study of streptozotocin-induced diabetes in rats

BACKGROUND

This long-term (2.3 years) study determines the temporal relationship between systemic glucose levels and the progression of diabetic retinopathy during the natural course of streptozotocin-induced diabetes in rats.

METHODS

Of 367 rats, 200 were randomly assigned into a group injected with streptozotocin (50 mg.kg(-1)) and 167 into a control group. Subsets of the rats were killed at 6, 28, 40, 65, 90 and >100 weeks post induction to allow the severity of retinopathy to be assessed quantitatively and qualitatively by trypsin digests of the retinal vasculature. Concurrently blood glucose, body weight and death rate were monitored.

RESULTS

Three glycemic phases were observed in the streptozotocin rats. In phase 1 (0 to 36-40 weeks) hyperglycemia was established and maintained. In phase 2 (36-40 to 84-90 weeks) normoglycemia was restored, and maintained during phase 3 (84-90 to 120 weeks). Control rats were normoglycemic throughout. The retinal microangiopathy was marked at 28 weeks during phase 1, developed more slowly in phase 2 and continued to worsen with loss of capillaries in all retinas and saccular microaneurysms present in 50% of retinas in phase 3. Cumulative death rate in streptozotocin rats also followed three phases, with maximum vulnerability occurring between 28 and 40 weeks. Body weight was significantly lower in streptozotocin rats throughout, increasing slowly in phase 1, then more rapidly during and after spontaneous glycemic recovery.

CONCLUSION

The worsening retinopathy, despite sustained recovery to normoglycemia, implies that good glucose control alone does not stop the progression of the retinal microangiopathy at this late stage.

Characterization of mouse peroxiredoxin I genomic DNA and its expression

Peroxiredoxins (Prxs) are a newly defined family of anti-oxidant proteins that have been implicated, via their anti-oxidant activity, in a number of cellular functions, including cell proliferation and differentiation, protection of other proteins from oxidative damage, and intracellular signaling. We isolated genomic DNA sequences of the Prx I genes from the mouse, and characterized their molecular genetic features. Prx I was found to form a small gene family with two and three members; one functional and two pseudogenes. The Prx I-1 gene has splice donor/acceptor site sequences and five or six exons, whereas the Prx I-2 clone has several structural features characteristic of a typical retroposon found to have ORF sequences. We analyzed the expression of pseudogenes, which were not expressed on the transcription levels in the investigated organs. The functional copy of the Prx I-1 gene was expressed abundantly in liver and kidney of the adult, as well as in early developing embryos. This report, together with amino acid/nucleotide sequence similarity between human and mice, provides a basis for speculating on an even earlier event in the evolution of the Prx I gene family, i.e. the Prx I gene was well conserved in human and mice via its anti-oxidant activity.