Prasugrel-based de-escalation vs. conventional therapy after percutaneous coronary intervention in ACS patients according to the renal function

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): A consortium of six companies in Korea (Daiichi Sankyo, Boston Scientific, Terumo, Biotronik, Qualitech Korea, and Dio).

Background

Patients with coronary artery disease and impaired renal function are at higher risk for both bleeding and ischemic adverse events after percutaneous coronary intervention (PCI).

Purpose

We assessed the efficacy and safety of a prasugrel based de-escalation strategy in patients with impaired renal function.

Methods

We conducted a post-hoc analysis of the HOST-REDUCE-POLYTECH-ACS study. Patients with available estimated glomerular filtration rate (eGFR) (n=2,311) were categorized into three groups. (high eGFR: ≥90 mL/min; intermediate eGFR: ≥60 and <90 mL/min; low eGFR: <60 mL/min). The endpoints were bleeding outcomes (Bleeding Academic Research Consortium type 2, or higher), ischemic outcomes (cardiovascular death, myocardial infarction, stent thrombosis, repeat revascularization, and ischemic stroke), and net adverse clinical events (all cause death, BARC 2 or greater bleeding, MI, stent thrombosis, repeat revascularization, and ischemic stroke) at 1 year follow-up. The hazard ratio (HR) and 95% Confidence interval (CI) were calculated from the multivariate Cox proportional hazard regression analysis. Covariates that were considered clinically meaningful were included. The probability risk ratio was obtained by dividing ischemic hazard function from the bleeding hazard function.

Results

With respect to net adverse clinical events, prasugrel de-escalation was beneficial regardless of baseline renal function (p for interaction = 0.508). The relative reduction in bleeding risk from prasugrel de-escalation was higher in the low eGFR group compared with that from both the intermediate and high eGFR groups (relative reduction: 64% [HR 0.36, 95% CI 0.15–0.83] vs. 50% [HR 0.50, 95% CI 0.28-0.90] and 52% [HR 0.48, 95% CI 0.21-1.13] for low, intermediate, and high eGFR groups, p for interaction=0.646). Ischemic risk from prasgurel de-escalation was not significant in all eGFR groups ([HR 1.18, 95% CI 0.47-2.98], [HR 0.95, 95% CI 0.53-1.69], and [HR 0.61, 95% CI 0.26-1.39)], respectively, p for interaction=0.119). The probability risk ratio was highest in low eGFR group (1.06 vs. 1.26 vs. 1.36, for high, intermediate, and low eGFR groups, respectively, p for trend<0.001), suggesting higher relative bleeding risk above ischemic risk. Within those randomized to the de-escalation strategy, the mean probability risk ratio was not significantly different according to renal function (0.89, vs. 0.84 vs. 0.80 respectively, p for trend = 0.053), which was in contrast to those randomized to the conventional strategy where the mean probability risk ratio increased significantly as renal function decreased (1.24 vs. 1.67 vs. 1.94 respectively, p for trend<0.001).

Conclusion

The beneficial effect of prasugrel-based de-escalation strategy was consistent regardless of the baseline renal function, which was mostly driven by a reduction in bleeding risk which was greatest in those with low eGFR.

Aspirin vs. Clopidogrel as a Chronic maintenance monotherapy after PCI in patients with high ischemic risk and high bleeding risk: Subgroup analysis of the HOST-EXAM trial

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

on behalf of the HOST-EXAM investigators

Background

The HOST-EXAM randomized clinical trial recently performed a comparison of clopidogrel monotherapy vs. aspirin monotherapy in patients requiring indefinite antiplatelet monotherapy after percutaneous coronary intervention (PCI). This study randomized 5,438 patients who maintained dual antiplatelet therapy without clinical events for 6–18 months after PCI with drug-eluting stents (DES) to receive a monotherapy agent of clopidogrel 75 mg once daily or aspirin 100 mg once daily for 24 months. During the 24-month follow-up, the primary outcome (a composite of all-cause death, non-fatal myocardial infarction, stroke, readmission due to acute coronary syndrome, and Bleeding Academic Research Consortium (BARC) bleeding type 3 or greater) rate was significantly lower in the clopidogrel group (hazard ratio [HR] 0.73 [95% CI 0.59–0.90]; p = 0.0035). However, it is uncertain whether the beneficial effect of clopidogrel will be consistent in patients with high ischemic risk or those with high bleeding risk.

Methods

This is a post-hoc analysis of the HOST-EXAM trial. A high ischemic risk was defined as those who had at least 1 of the following procedural features: 3 vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation PCI, total stent length >60 mm, or left main PCI. Patients with high bleeding risk were defined according to the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria. The co-primary outcome were thrombotic endpoints (a composite of cardiac death, non-fatal myocardial infarction, ischemic stroke, readmission due to acute coronary syndrome, and definite or probable stent thrombosis) and bleeding endpoints (BARC type ≥2 bleeding events) at 24-month follow-up.

Results

 Among the total population, 22.1% had high ischemic risk and 21.4% had high bleeding risk. Complex PCI was not associated with a higher risk of thrombotic endpoints, nor bleeding endpoints. For patients with a high bleeding risk, these patients had a higher risk of both thrombotic endpoints (HR 1.545, 95% CI 0.141-2.092, p = 0.005) and bleeding endpoints (HR 3.418, 95% CI 2.413-4.840, p < 0.001). The primary results focusing on the interaction between high ischemic risk, high bleeding and the antiplatelet regimen will be presented.

Conclusion

The current post-hoc analysis of the HOST-EXAM trial will evaluate the efficacy of clopidogrel monotherapy vs. aspirin monotherapy during the chronic maintenance period after PCI, in patients with high ischemic risk or those with high bleeding risk.

Dual antithrombotic therapy on early clinical outcomes in patients with atrial fibrillation after percutaneous coronary intervention: a nationwide study in the era of NOAC

Background/Introduction

Recent evidence has confirmed low bleeding risk with double antithrombotic therapy, combining oral anticoagulant (OAC) and single platelet inhibitor, in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI). Among the Asian AF population, most of the patients received dual antiplatelet therapy (DAPT) without OACs, even after the introduction of non-vitamin K oral anticoagulants (NOACs).

Purpose

The current nationwide study assessed 3-month ischemic and bleeding risks of DAPT in comparison to triple antithrombotic therapy among the Korean AF population undergoing PCI.

Methods

We analyzed the claims records of 11,039 patients (mean age 70 years, 66.3% male, and mean CHA2DS2-VASc score 3.2) between 2013 to 2018. Patients were categorized into triple therapy group with vitamin K antagonists (VKAs-TT), or NOACs (NOACs-TT), and DAPT group according to the antithrombotic therapy after PCI. 3-month risks of ischemic stroke, non-fatal myocardial infarction, any in-hospital death, and major bleeding were compared between groups after baseline adjustment using inverse probability weighting.

Results

A total of 1,786, 1,997, and 7,256 patients were allocated to the VKAs-TT, NOACs-TT, and DAPT groups. The DAPT group had a higher prevalence of prior MI and coronary revascularization, but had lower thromboembolic and bleeding risks than the triple antithrombotic therapy groups (mean CHA2DS2-VASc score 3.8, 4.1, and 3.5; and mean HAS-BLED score 3.3, 3.4, and 3.1 for VKAs-TT, NOACs-TT, and DAPT groups, respectively). The NOACs-TT group was associated with a lower risk of ischemic stroke (hazard ratio [HR] 0.38, 95% confidence interval [CI] 0.20–0.70) and any in-hospital death (HR 0.70, 95% CI 0.49–0.98) compared with the VKAs-TT group. The DAPT group showed a lower risk of ischemic stroke (HR 0.41, 95% CI 0.27–0.63) and major bleeding (HR 0.55, 95% CI 0.37–0.84) than the VKAs-TT group, especially in patients without prior OAC treatment. The DAPT group showed a comparable ischemic risk against the NOACs-TT group, although the risk of major bleeding was lower in the DAPT group, especially among old age (HR 0.47, 95% CI 0.29–0.78) or OACs-naive patients (HR 0.50, 95% CI 0.29–0.86).

Conclusion

Among the Asian AF population, using short-term DAPT for 3-month after PCI was associated with a lower risk of bleeding without increasing ischemic risk compared to triple antithrombotic therapy with OAC. This may be a therapeutic option in very high bleeding risk patients who have had complex PCI necessitating focus on DAPT in the initial 3 month period.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): This study was supported by grant no 3020200200 from the Seoul National University Hospital Research Fund, by the Korea Medical Device Development Fund grant funded by the Korea government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, Republic of Korea, the Ministry of Food and Drug Safety) (Project Number: 202013B14), and by the Korea National Research Foundation funded by the Ministry of Education, Science and Technology (grant 2020R1F1A106740). Figure 1Figure 2

A novel index reflecting both anatomical and physiologic parameters in coronary artery disease, the FFR adjusted SYNTAX score (FaSs)

Background

Various physiology-based indices have been proposed to predict adverse clinical events in patients with coronary artery disease (CAD), such as the sum of three vessel-fractional flow reserve (3v-FFR), and the functional SYNTAX score (fSS). However, these values could not fully reflect the anatomical factors, which remains as a barrier for clinical application of these indices.

Purpose

To propose a novel index which can reflect both anatomical and physiologic features in CAD patients, and evaluate the additional predictive value for cardiovascular adverse events compared to previous indices.

Methods

For an index which can reflect both anatomical and physiologic features, we proposed the FFR adjusted SYNTAX score (FaSs). The FaSs is calculated by adding the product of the SYNTAX score and `1-FFR', for all three major coronary arteries. Among the 1136 patients who enrolled at 3V FFR-FRIENDS study, we investigated 866 patients, after excluding those who had missing variables. The 3v-FFR, fSS and FaSs were calculated, derived from the baseline FFR and SYNTAX score. Patients were divided into two groups according to the median value of each index. The primary endpoint was major adverse cardiac events (MACE, a composite of cardiac death, myocardial infarction and ischemia-driven revascularization) at 2 years follow-up.

Results

Among the total population, MACE occurred in 35 (4.04%) patients. Using the median value in a multivariable COX regression model, only FaSs was associated with an increased risk of MACE, (Hazard Ratio [HR] 5.256, 95% confidence interval [CI] 2.014–13.720), while 3v-FFR (HR 1.383, 95% CI 0.685–2.790) and fSS (HR 1.640, 95% CI 0.830–3.243) were not significantly associated with a higher risk of MACE. This was also observed in the Kaplan Meier survival curve analysis (log-rank p value: p<0.001 for FaSs, 0.153 for 3v-FFR, and 0.061 for fSS; Figure 1) The sensitivity and specificity of the FaSs was 85.7% and 51.6%, which was higher compared to the 3v-FFR (62.9% and 49.3%, respectively) and fSS (57.1% and 58.5%, respectively). When these indices were combined with clinical risk factors (age, sex, hypertension, diabetes, hyperlipidemia, chronic renal failure, LVEF<40%), FaSs was superior compared with 3v-FFR and fSS assessed in regards of the predictive accuracy for MACE (Figure 2).

Conclusion

The FaSs, which is a novel index calculated by a formula using the SYNTAX score and FFR, showed a superior predictive value for MACE compared to previous indices. Our results confirm the importance of considering both anatomical and physiologic parameters in evaluating the patient's risk for cardiovascular adverse outcomes.

Funding Acknowledgement

Type of funding sources: None.

Radiomics Study of Thyroid Ultrasound for Predicting BRAF Mutation in Papillary Thyroid Carcinoma: Preliminary Results

BACKGROUND AND PURPOSE

It is not known how radiomics using ultrasound images contribute to the detection of BRAF mutation. This study aimed to evaluate whether a radiomics study of gray-scale ultrasound can predict the presence or absence of B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutation in papillary thyroid cancer.

MATERIALS AND METHODS

The study retrospectively included 96 thyroid nodules that were surgically confirmed papillary thyroid cancers between January 2012 and June 2013. BRAF mutation was positive in 48 nodules and negative in 48 nodules. For analysis, ROIs from the nodules were demarcated manually on both longitudinal and transverse sonographic images. We extracted a total of 86 radiomics features derived from histogram parameters, gray-level co-occurrence matrix, intensity size zone matrix, and shape features. These features were used to build 3 different classifier models, including logistic regression, support vector machine, and random forest using 5-fold cross-validation. The performance including accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve, of the different models was evaluated.

RESULTS

The incidence of high-suspicion nodules diagnosed on ultrasound was higher in the BRAF mutation-positive group than in the mutation-negative group (P  =  .004). The radiomics approach demonstrated that all classification models showed moderate performance for predicting the presence of BRAF mutation in papillary thyroid cancers with an area under the curve value of 0.651, accuracy of 64.3%, sensitivity of 66.8%, and specificity of 61.8%, on average, for the 3 models.

CONCLUSIONS

Radiomics study using thyroid sonography is limited in predicting the BRAF mutation status of papillary thyroid carcinoma. Further studies will be needed to validate our results using various diagnostic methods.

P6534Prognostic implication of serum cystatin C and creatinine-based glomerular filtration rate ratio in coronary disease patients receiving PCI: a surrogate of low muscle mass and a predictor of mortality

Background

Low muscle mass results in impaired exercise capacity and is related with poor prognosis in chronic diseases. Although the ratio of serum creatinine (Scr) to cystatin C (Scys) is known as a surrogate marker of body muscle mass, the value of this marker is unclear in the patients with coronary artery disease (CAD).

Purpose

We assessed the clinical significance of two markers representing body muscle mass, the ratio of Scr to Scys (Scr/Scys), and ratio of estimated glomerular filtration rate by Scys to Scr (eGFRcys/eGFRcr).

Methods

We analyzed patients enrolled in a single tertiary center prospective percutaneous coronary intervention (PCI) registry that had Scr and Scys levels simultaneously measured before PCI. Optimal cut-off values of Scr/Scys and eGFRcys/eGFRcr, and their prognostic impact on 3-year mortality after PCI were analyzed. Subgroup analysis according to various demographics and risk factors was performed.

Results

A total of 1,928 patients who underwent PCI for significant CAD were analyzed (age 65.2±9.9 years, 70.8% men). Both Scr/Scys and eGFRcys/eGFRcr showed strong correlation with estimated proportion of muscle mass. Cut-off values of Scr/Scys discriminating 3-year death were 1.0 for men and 0.8 for women, while those of eGFRcys/eGFRcr were 1.1 for men and 1.0 for women. Both Scr/Scys- and eGFRcys/eGFRcr-based low muscle mass groups showed significantly higher risk of death, after adjusting for 7 selected covariates including age. The additional discriminative power of low muscle mass group on the predictive model was greater in the group determined by eGFRcys/eGFRcr than Scr/Scys. Low eGFRcys/eGFRcr values showed additional prognostic impact especially in patients older than 65 years, non-obese, men, chronic kidney disease, and current smokers.

Conclusions

Low muscle mass was an independent prognostic indicator in the patients who underwent coronary stenting. eGFRcys/eGFRcr was identified as a useful surrogate of muscle mass, which may be used to detect vulnerable patients with low muscle mass at high risk for future events.

Acknowledgement/Funding

None

Inhibition of microRNA-449a prevents IL-1β-induced cartilage destruction via SIRT1

OBJECTIVE

SIRT1 has anti-inflammatory as well as protective effects in chondrocytes. The object of this study was to investigate whether microRNA-449a regulates expression of SIRT1, which inhibits expression of catabolic genes in IL-1β-induced cartilage destruction.

MATERIALS AND METHODS

MicroRNA-449a expression was determined in OA chondrocytes and IL-1β-induced chondrocytes by real-time PCR. MicroRNA-449a binding sites on the 3'-UTR of SIRT1 mRNA and binding site conservation were examined using microRNA target prediction tools. SIRT1-overexpressing or knockdown chondrocytes were transfected with microRNA-449a or anti-microRNA-449a mimic and stimulated by IL-1β. Expression of catabolic and anabolic genes was examined by real-time PCR and western blotting. Finally, positive effects of anti-microRNA-449a on expression of these genes were confirmed by western analysis of OA chondrocytes.

RESULTS

Expression of microRNA-449a was increased in OA chondrocytes and IL-1β-induced chondrocytes. MMP-13 expression was enhanced, whereas type II collagen and SIRT1 expression were decreased in IL-1β-induced chondrocytes. SIRT1 overexpression resulted in decreased expression of catabolic genes such as MMPs and ADAMTSs in response to IL-1β, but these effects were moderated by microRNA-449a. Suppression of microRNA-449a by anti-microRNA-449a inhibited expression of catabolic genes despite IL-1β stimulation, but these effects were abolished in SIRT1 knockdown chondrocytes. Furthermore, expression of catabolic genes was decreased and expression of type II collagen as well as SIRT1 was restored by anti-microRNA-449a in OA chondrocytes as well as in IL-1β-induced chondrocytes.

CONCLUSION

Silencing of microRNA-449a had a protective effect, inhibiting catabolic gene expression and restoring anabolic gene expression, by targeting SIRT1 in IL-1β-induced cartilage destruction.

Cross-sectional scanning thermal microscopy of ErAs/GaAs superlattices grown by molecular beam epitaxy

Scanning thermal microscopy has been implemented in a cross-sectional geometry, and its application for quantitative, nanoscale analysis of thermal conductivity is demonstrated in studies of an ErAs/GaAs nanocomposite superlattice. Spurious measurement effects, attributable to local thermal transport through air, were observed near large step edges, but could be eliminated by thermocompression bonding to an additional structure. Using this approach, bonding of an ErAs/GaAs superlattice grown on GaAs to a silicon-on-insulator wafer enabled thermal signals to be obtained simultaneously from Si, SiO2, GaAs, and ErAs/GaAs superlattice. When combined with numerical modeling, the thermal conductivity of the ErAs/GaAs superlattice measured using this approach was 11 ± 4 W m(-1) K(-1).

P42 Ebp1 regulates the proteasomal degradation of the p85 regulatory subunit of PI3K by recruiting a chaperone-E3 ligase complex HSP70/CHIP

The short isoform of ErbB3-binding protein 1 (Ebp1), p42, is considered to be a potent tumor suppressor in a number of human cancers, although the mechanism by which it exerts this tumor-suppressive activity is unclear. Here, we report that p42 interacts with the cSH2 domain of the p85 subunit of phosphathidyl inositol 3-kinase (PI3K), leading to inhibition of its lipid kinase activity. Importantly, we found that p42 induces protein degradation of the p85 subunit and further identified HSP70/CHIP complex as a novel E3 ligase for p85 that is responsible for p85 ubiquitination and degradation. In this process, p42 couples p85 to the HSP70/CHIP-mediated ubiquitin–proteasomal system (UPS), thereby promoting a reduction of p85 levels both in vitro and in vivo. Thus, the tumor-suppressing effects of p42 in cancer cells are driven by negative regulation of the p85 subunit of PI3K.

Inhibition of adipogenesis in 3T3-L1 cells and suppression of abdominal fat accumulation in high-fat diet-feeding C57BL/6J mice after downregulation of hyaluronic acid

OBJECTIVE

Adipogenesis can be spatially and temporally regulated by extracellular matrix (ECM). We hypothesized that the regulation of hyaluronic acid (HA), a component of the ECM, can affect adipogenesis in fat cells. The effects of HA on adipogenesis were investigated in vitro in 3T3-L1 cells and in vivo in high-fat diet-feeding C57BL/6J mice.

METHODS

We investigated the effects of HA by degradation of pre-existing or synthesized HA and artificial inhibition of HA synthesis in adipogenesis.

RESULTS

In vitro adipogenesis in 3T3-L1 cells was inhibited by treating them with exogenous hyaluronidase (HYAL) and with 4-methylumbelliferone, which inhibited the synthesis of HA in a concentration-dependent manner. In vivo, abdominal fat accumulation in high-fat diet-feeding C57BL/6J mice was suppressed by exogenous HYAL 10(4) IU injections, which was associated with reduction of lipid accumulation in liver and increase of insulin sensitivity.

CONCLUSION

Changes in the ECM such as accumulation of high molecular weight of HA by HAS and degradation of HA by endogenous HYAL were essential for adipogenesis both in vitro and in vivo.

Effect of temperature on optical and electronic properties of InGaP/InGaAIP multiple quantum wells

The optical and electronic properties in an InGaP/InGaAIP multiple quantum well (MQW) grown by using molecular-beam epitaxy utilizing the digital alloy technique were investigated through temperature-dependent photoluminescence (PL) measurements and numerical calculations. The high-resolution transmission electron microscopy images showed that the sample clearly displayed the InGaP wells and the InGaAIP barriers and separate confinement heterostructure layers. The PL measurements at various temperatures were performed to investigate the interband transitions of the InGaP/InGaAIP MQW. The electronic subband energies and the wavefunctions in the InGaP/InGaAIP MQW at several temperatures were determined by using a finite element method employing the standard 8-band k x p Lagrangian. The numerical results for optical interband transition energies from the ground state electron subband to the ground state heavy-hole subband of the InGaP/InGaAIP MQW at various temperatures were in reasonable agreement with the excitonic transition energies observed in the PL measurements.

Interleukin-13/-4-induced oxidative stress contributes to death of hippocampal neurons in aβ1-42-treated hippocampus in vivo

AIMS

The present study examined whether Aβ(1-42) can induce endogenous expression of interleukin-13 (IL-13) or (IL-4) within activated microglia in the rat hippocampus in vivo. We further investigated whether these cytokines mediate ROS/RNS generation through activation of NADPH oxidase and/or inducible nitric oxide synthase (iNOS), and thus contribute to the degeneration of hippocampal neurons in vivo.

RESULTS

Here, we show that IL-13 and IL-4, endogenously expressed in Aβ(1-42)-activated microglia in hippocampus in vivo, contribute to degeneration of hippocampal neurons in vivo. Neutralization of IL-13 and IL-4 protected hippocampal neurons in vivo against neurotoxicity by inhibiting activation of microglial NADPH oxidase and iNOS, resulting in attenuation of ROS generation and oxidative damage of protein, lipid and DNA.

INNOVATION

To our knowledge, this is the first study to demonstrate the possible involvement of endogenously expressed IL-13 and/or IL-4 in activated microglia after Aβ(1-42) injection in the degeneration of hippocampal neurons in vivo. The current findings suggest that the deleterious effects of microglia-derived endogenous IL-13 and/or IL-4 are involved in oxidative stress-mediated neurodegenerative diseases, such as AD.

CONCLUSION

We carefully hypothesize that IL-13 and IL-4, well-known as anti-inflammatory cytokines might serve as neurotoxic mediators by enhancing microglia-derived oxidative stress in Aβ(1-42)-treated hippocampus in vivo.

Subclinical cervical osteochondroma presenting as brown-sequard syndrome after trivial neck trauma

Osteochondroma is a rare condition in the spine that may be indolent due to its slow growth. The authors present a case of 32-year-old man with subclinical osteochondroma in the cervical spine presenting as Brown-Sequard syndrome after trivial neck trauma. After resection of the tumor through hemilaminectomy, his symptoms were improved with mild residual sequelae.

Extranodal natural killer/T-cell lymphoma from skin or soft tissue: suggestion of treatment from multinational retrospective analysis

BACKGROUND

Clinical features and outcomes of extranodal natural killer/T-cell lymphoma (ENKL) arising from extranasal sites are not fully understood. The purpose of this study was to study the prognosis and treatment outcome of skin/soft tissue primary ENKL.

PATIENTS AND METHODS

This multicenter retrospective study included 48 patients with skin/soft tissue primary ENKL diagnosed from 1993 to 2010.

RESULTS

Patients with Ann Arbor stage I, T1-2N0M0 by International Society for Cutaneous Lymphomas-European Organization of Research and Treatment of Cancer TNM (tumour-node-metastasis) stage, International prognostic index score of 0-1, and a Korean prognostic index (KPI) score of 0-1 were associated with better survival. Four of five patients with T1-2N0M0 disease achieved complete response with radiation alone. In disseminated disease, only 6 of 13 patients responded to anthracycline-containing chemotherapy, and all the two patients receiving SMILE showed response.

CONCLUSION

In conclusion, we identified the prognostic value of KPI, and we suggest a treatment recommendation according to the TNM (tumour-node-metastasis) stage. Radiotherapy with/without chemotherapy seemed to be optimal in localized disease. In advanced stages, a more aggressive treatment regimen with newer agents should be sought.

Neurotoxic manifestations of an overdose intrathecal injection of gadopentetate dimeglumine

The intravenous administration of gadopentetate dimeglumine (GD) is relatively safe and rarely causes systemic toxicity in the course of routine imaging studies. However, the general safety of intrathecal GD has not been established. We report a very rare case of an overdose intrathecal GD injection presenting with neurotoxic manifestations, including a decreased level of consciousness, global aphasia, rigidity, and visual disturbance.

Risk of hemorrhagic gastropathy associated with colonoscopy bowel preparation using oral sodium phosphate solution

BACKGROUND AND STUDY AIMS

Oral sodium phosphate (NaP) solution is widely used for colonoscopy bowel preparation and it may cause aphthous ulcers in the colon. Our aim was to evaluate whether oral NaP solution is associated with gastric mucosal lesions.

METHODS

A total of 20 070 individuals underwent esophagogastroduodenoscopy (EGD) with colonoscopy, and 4271 individuals underwent EGD without colonoscopy, for cancer screening. Oral NaP solutions were used for bowel preparation prior to colonoscopy. Hemorrhagic gastropathy was graded using a five-point scale for erosive mucosal injury. The effect of NaP bowel preparation on hemorrhagic gastropathy was estimated using multiple logistic regression analysis with odds ratios (ORs) and 95 % confidence intervals (CIs).

RESULTS

The incidence of hemorrhagic gastropathy was 1.6 % (70/4271) in the EGD only group and 4.0 % (809/20 070) in the EGD with colonoscopy group ( P < 0.001, unadjusted OR 2.55, 95 %CI 1.99 - 3.27). The ORs for mild (grade 1 - 2), moderate (grade 3), and severe (grade 4) hemorrhagic gastropathy according to NaP use were 1.92 (95 %CI 1.45 - 2.54), 4.72 (95 %CI 2.65 - 8.47), and 5.99 (95 %CI 1.46 - 24.63), respectively. After adjustment for confounding factors, NaP solution was a significant risk factor for acute hemorrhagic gastropathy in the multivariate analysis (OR 1.92, 95 %CI 1.34-2.74). In addition, male sex, a body mass index (kg/m (2)) of less than 20, concurrent use of antihypertensive or nonsteroidal anti-inflammatory drugs, and duodenal ulcers were independently associated with the development of hemorrhagic gastropathy. HELICOBACTER PYLORI infection and atrophic gastritis were negatively associated with hemorrhagic gastropathy.

CONCLUSION

Oral NaP bowel preparation for colonoscopy was associated with hemorrhagic gastropathy.

A Retrospective Study on Intracerebral Haemorrhage Reduction by Mri versus Ct in Intravenous Thrombolysis for Acute Ischaemic Stroke

Introduction

Multimodal MRI may be an effective tool for selecting suitable acute ischaemic stroke patients for thrombolysis, reducing the risk of haemorrhage. In this study, we demonstrated the usefulness of our central alerting system to reduce door-to-needle time for thrombolysis following MRI. This system allowed timely intervention and reduced the rate of symptomatic haemorrhage.

Methods

We reviewed the records of 73 patients with hyperacute ischaemic stroke who received intravenous (IV) tissue plasminogen activator (t-PA) between January 2006 and December 2007 following the adoption of a central stroke alerting system in our hospital.

Results

Of the 73 patients who received IV t-PA, 44 were based on CT and 29 on MRI findings. The door-to-needle time was 10 minutes longer for the MRI group (49.9±23.2 min) compared to the CT group (39.6±19.7 min) but it was still within the recommended 60 minutes time frame. On the other hand, the rate of symptomatic haemorrhage was lower, though insignificantly, in the MRI group (0%) compared to the CT group (13.6%) (p=0.08).

Conclusions

In this study, we demonstrated that the combination of diagnostic MRI and a central alerting system might reduce the rate of symptomatic haemorrhage without compromising the door-to-needle time.

Effect of isoflurane on the beta-adrenergic and endothelium-dependent relaxation of pig cerebral microvessels after cardiopulmonary bypass

We examined the direct vasomotor effect of isoflurane as well as its effect on endothelium-dependent and beta-adrenergic vasodilation of cerebral microcirculation following either normothermic cardiopulmonary bypass (CPB) or profoundly hypothermic CPB with circulatory arrest. Pigs were placed on CPB; the systemic temperature was either maintained at 37 degrees C or lowered to 15 degrees C with 60 minutes of circulatory arrest. After 2 hours of CPB, the animals were separated from CPB; 15 minutes later the brain was quickly harvested in cold Krebs solution. Control animals were not instrumented and their brains were similarly harvested. Arteries of approximately 100 microm were dissected and changes in diameter monitored by in vitro videomicroscopy. Following preconstriction with the thromboxane analogue U46619 1 micromol/L, percent relaxation to the endothelium-dependent dilator adenosine diphosphate (ADP) 10(-9) to 10(-4) mol/L, the endothelium-independent dilator sodium nitroprusside (SNP) 10(-9) to 10(-4) mol/L, or the beta-adrenergic agonist isoproterenol 10(-12) to 10(-4) mol/L was measured either in the presence or absence of isoflurane 2%. Additionally, with or without preconstriction with U46619 1 micromol/L, vessel diameter changes were monitored with increasing concentrations of isoflurane 0-3%. Dose-response curves were compared by two-way analysis of variance. Vasodilation to ADP or isoproterenol, but not SNP, was attenuated after normothermic CPB (N-CPB) or profoundly hypothermic CPB (PH-CPB). Although isoflurane attenuated vasodilation of control vessels to ADP or isoproterenol, isoflurane did not further attenuate vasodilation to ADP or isoproterenol after N-CPB or PH-CPB. The direct vasomotor effect of isoflurane depended on the preexisting tone of the vessels, constricting vessels without preconstriction and dilating them after preconstriction. These findings may have implications on the incidence of neuropsychological dysfunction after CPB and use of isoflurane.

Obesity and weight gain as risk factors for erosive oesophagitis in men

BACKGROUND

Although obesity and weight gain increase the risk for symptoms of gastro-oesophageal reflux disease, their association with erosive oesophagitis is still unclear in the male population.

AIM

To evaluate, in men, the association of body mass index (BMI) and weight gain with endoscopically proven erosive oesophagitis.

METHODS

A total of 8571 Korean men in a comprehensive screening cohort were enrolled. Effects of BMI and abdominal obesity on erosive oesophagitis were estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression analysis. We also evaluated the association between erosive oesophagitis and BMI change after 1-3 years.

RESULTS

The prevalence of erosive oesophagitis was 6.4% (552/8571). In univariate analysis, the ORs for erosive oesophagitis increased as BMI or waist circumference increased (P for trend <0.001, both). In multivariate analysis, OR for erosive oesophagitis increased as BMI increased (P for trend = 0.002), while the significance of waist circumference was attenuated (P for trend = 0.13). Increase in BMI (>or=1 kg/m2) was associated with persistence of erosive oesophagitis (OR = 2.83, 95% CI: 1.01-7.92, P = 0.04) and new development of the disease (OR = 2.13, 95% CI: 1.38-3.28, P = 0.001) compared with BMI change less than 1 kg/m2.

CONCLUSIONS

Elevated BMI and weight gain have a significant association with erosive oesophagitis.

IMVP-16/Pd followed by high-dose chemotherapy and autologous stem cell transplantation as a salvage therapy for refractory or relapsed peripheral T-cell lymphomas

The present study aimed to analyse the treatment outcome of IMVP-16/Pd (ifosfamide, methotrexate, etoposide and prednisone) followed by high-dose chemotherapy and autologous stem cell transplantation (HDC/ASCT) for patients with peripheral T-cell lymphomas (PTCLs) who were previously treated with CHOP. Since 1995, 32 PTCL patients were treated with IMPV-16/Pd. Nine of 32 patients achieved a response (5 demonstrating complete response (CR) and 4 partial response), with an overall response rate of 28.1% (95% onfidence interval 0.12-0.45). Considering histopathologic subtypes, 3 of 4 relapsed natural killer (NK)/T-cell lymphoma patients (75%) achieved CR, but only 1 of 6 in non-NK/T-cell lymphoma patients (16.7%) achieved CR (P = 0.19). Six of 9 IMVP-16/Pd sensitive patients underwent HDC/ASCT. Three of them relapsed after 3, 4 and 15 months, respectively, of HDC/ASCT. Estimated 3-year overall survival and progression-free survival rates were 14.2% and 12.2%, respectively. Multivariate analysis revealed that responsiveness to first-line CHOP was a significant prognostic factor (P < 0.05). These results indicate that IMVP-16/Pd followed by HDC/ASCT appears to be an effective salvage regimen, especially for NK/T-cell lymphoma.

Obesity and weight gain as risk factors for erosive oesophagitis in men

BACKGROUND

Although obesity and weight gain increase the risk for symptoms of gastro-oesophageal reflux disease, their association with erosive oesophagitis is still unclear in the male population.

AIM

To evaluate, in men, the association of body mass index (BMI) and weight gain with endoscopically proven erosive oesophagitis.

METHODS

A total of 8571 Korean men in a comprehensive screening cohort were enrolled. Effects of BMI and abdominal obesity on erosive oesophagitis were estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression analysis. We also evaluated the association between erosive oesophagitis and BMI change after 1-3 years.

RESULTS

The prevalence of erosive oesophagitis was 6.4% (552/8571). In univariate analysis, the ORs for erosive oesophagitis increased as BMI or waist circumference increased (P for trend <0.001, both). In multivariate analysis, OR for erosive oesophagitis increased as BMI increased (P for trend = 0.002), while the significance of waist circumference was attenuated (P for trend = 0.13). Increase in BMI (>or=1 kg/m2) was associated with persistence of erosive oesophagitis (OR = 2.83, 95% CI: 1.01-7.92, P = 0.04) and new development of the disease (OR = 2.13, 95% CI: 1.38-3.28, P = 0.001) compared with BMI change less than 1 kg/m2.

CONCLUSIONS

Elevated BMI and weight gain have a significant association with erosive oesophagitis.

Spinal dural arteriovenous fistula with supply from the lateral sacral artery-case report and review of literature-

The authors report a case of spinal dural arteriovenous fistula (SDAVF) that is supplied by a lateral sacral artery. A 73-year-old male presented with gait disturbance that had developed 3 years ago. Spinal magnetic resonance imaging suggested a possible SDAVF. Selective spinal angiography including the vertebral arteries and pelvic vessels showed the SDAVF fed by left lateral sacral artery. The patient was subsequently treated with glue embolization. Three days after the embolization procedure, his gait disturbance was much improved.

Vertebral artery dissection: natural history, clinical features and therapeutic considerations

When a tear occurs in one of the major cervicocerebral arteries and allows blood to enter the wall of the artery and split its layers, the result is either stenosis or aneurysmal dilatation of the vessel. Vertebral artery dissection (VAD) is an infrequent occurrence but is a leading cause of stroke in young and otherwise healthy patients. This article discusses recent developments in understanding of the epidemiology and pathogenesis of VAD and the various clinical manifestations, methods of diagnosis, and approaches to treatment.

Production of transgenic recloned piglets harboring the human granulocyte-macrophage colony stimulating factor (hGM-CSF) gene from porcine fetal fibroblasts by nuclear transfer

We used nuclear transfer (NT) to develop transgenic female pigs harboring goat beta-casein promoter/human granulocyte-macrophage colony stimulating factor (hGM-CSF). The expression of hGM-CSF was specific to the mammary gland, and the glycosylation-derived size heterogeneity corresponded to that of the native human protein. Although various cell types have been used to generate cloned animals, little is currently known about the potential use of fibroblasts derived from a cloned fetus as donor cells for nuclear transfer. The developmental potential of porcine cloned fetal fibroblasts transfected with hGM-CSF was evaluated in the present study. Cloned fetal fibroblasts were isolated from a recipient following the transplantation of NT embryos. The cells were transfected with both hGM-CSF and the neomycin resistance gene in order to be used as donor cells for NT. Reconstructed embryos were implanted into six sows during estrus; two of the recipient sows delivered seven healthy female piglets with the hGM-CSF gene (confirmed with PCR and fluorescent in situ hybridization) and microsatellite analysis confirmed that the clones were genetically identical to the donor cells. The expression of hGM-CSF was strong in the mammary glands of a transgenic pig that died a few days prior to parturition (110 d after AI). These results demonstrated that somatic cells derived from a cloned fetus can be used to produce recloned and transgenic pigs.

Outcomes of surgical management of total colonic aganglionosis

PURPOSE

The purpose of this study was to assess the long-term clinical outcomes and bowel function of patients with total colonic aganglionosis (TCA) after surgery.

METHODS

The hospital records of 17 TCA patients treated surgically during 1985 to 2004 were reviewed. Long-term follow-up was done by telephone interviews with the parents.

RESULTS

Primary enterostomy was performed in 13 (76%) patients. In three (17%) patients, TCA was not suspected initially. They underwent conservative surgery primarily, which required a second operation soon after. One had transverse colectomy with ileostomy. By pathologic review, nine (53%) patients had small bowel involvement of aganglionosis. Six (35%) patients died before corrective surgery. They all had extensive small bowel involvement. Among 11 patients who had a corrective operation, 10 were treated with Martin's procedure. Long-term (mean 74 months) follow-up was available in seven patients, and the mean weight-for-age percentiles was 27.1% (range 5-50%), the frequency of defecation was three to five times a day in four patients (57%), one or two times a day in two patients (28%), and more than five times a day in one patient (15%).

CONCLUSIONS

TCA is difficult to diagnose; but once it is diagnosed correctly and treated by corrective surgery, outcomes seem promising. Martin's operation brought about a good outcome and enabled patients to have acceptable bowel habits. The prognosis is highly dependent on the extent of aganglionosis.

Prognostic model to predict survival following first-line chemotherapy in patients with metastatic gastric adenocarcinoma

BACKGROUND

This study was to devise a prognostic model for metastatic gastric cancer patients undergoing first-line chemotherapy.

PATIENTS AND METHODS

A retrospective analysis was carried out on 1455 gastric cancer patients, who received first-line chemotherapy from September 1994 to February 2005.

RESULTS

At multivariate level, poor prognostic factors were no previous gastrectomy [P = 0.003; relative risk (RR), 1.191; 95% confidence interval (CI) 1.061-1.338], albumin < 3.6 g/dl (P = or <0.001; RR, 1.245; 95% CI 1.106-1.402), alkaline phosphatase > 85 U/l (P = or <0.001; RR, 1.224; 95% CI 1.092-1.371), Eastern Cooperative Oncology Group performance status of two or more (P = or <0.001; RR, 1.690; 95% CI 1.458-1.959), the presence of bone metastases (P = 0.001; RR, 1.460; 95% CI 1.616-1.836), and the presence of ascites (P = or < 0.001; RR, 1.452; 95% CI 1.295-1.628). Of 1434 patients, 489 patients (34.1%) were categorized as low-risk group (zero to one factors), 889 patients (62.0%) as intermediate-risk group (two to four factors), and 56 patients (3.9%) as high-risk group (five to six factors). Median survival durations for low, intermediate, and high-risk groups were 12.5 months, 7.0 months, and 2.7 months, respectively.

CONCLUSIONS

This model should facilitate the individual patient risk stratification and thus, more appropriate therapies for each metastatic gastric cancer patient.

Staurosporin induces neurite outgrowth through ROS generation in HN33 hippocampal cell lines

Staurosporin, a specific inhibitor of PKC, is widely used in studies of signal transduction pathways. Previous studies have shown that staurosporin induces neurite outgrowth, but the underlying mechanisms remain unclear. Here we report that staurosporin induces neurite outgrowth in HN33 hippocampal cells. Two other PKC inhibitors, Go 6976 (specific for alpha- and beta-isoforms) and rotterlin (a selective inhibitor of PKC delta), have no neuritogenic effect. In addition, staurosporin specifically increases ROS generation. NAC, which inhibits the generation of ROS, suppresses the staurosporin-induced neurite outgrowth in HN33 cells. Further, H(2)O(2) causes neurite outgrowth. Taken together, these results confirm a neuritogenic effect of staurosporin and point to ROS as the signal mediator of staurosporin-induced neurite outgrowth in HN33 hippocampal cells. Theme: Development and regeneration Topic: Neurotrophic factors: receptors and cellular mechanisms.

Changes in the structure of nuclei after transfer to oocytes

Nuclear transfer and the potential for cloning animals have refocused attention on the oocyte. This focus is not limited to the use of the oocyte as a recipient in nuclear transfer procedures, but more broadly in terms of what factors are present in the oocyte that are responsible for establishing the developmental pattern of RNA synthesis and subsequent protein production. Deviations in the pattern of RNA synthesis can result in abortions, as well as abnormalities at birth. This paper will focus on the changes to nuclear structure that result from transfer to the cytoplasm of an oocyte, as well as some of the changes in the patterns of RNA synthesis that have been described.

Neuroprotective role of microglia expressing interleukin-4

Little is known about the underlying mechanisms responsible for the death of activated microglia and the functional consequences of the death of these cells, especially in vivo. We show here that intracortical injection of lipopolysaccharide (LPS) led to upregulation of interleukin-4 (IL-4) immunoreactivity, followed by a substantial loss of microglia 3 days later, as visualized by complement receptor type 3 (OX-42) immunostaining and tomato lectin staining. Cells positive for caspase-3 and terminal deoxynucleotidyl transferase mediated fluorescein-dUTP nick-end labeling (TUNEL) were also localized within LPS-activated microglia. IL-4 immunoreactivity was detected as early as 12 hr post-LPS, disappearing at 72 hr. Surprisingly, IL-4 immunoreactivity was detected exclusively in microglia, but not in astrocytes or neurons. In addition, IL-4-neutralizing antibodies markedly increased the survival of activated microglia at 3 days post-LPS. The expression of inducible nitric oxide synthase (iNOS) and tumor-necrosis factor (TNF)-alpha was sustained in parallel in activated microglia, consequently increasing neuronal cell death. To our knowledge, this study is the first to show the endogenous expression of IL-4 in LPS-activated microglia in vivo. Our findings suggest that IL-4 may regulate brain inflammation by inducing the death of activated microglia in vivo and increasing neuronal survival.

Nasal-type NK/T cell lymphoma: clinical features and treatment outcome

Nasal-type NK/T cell lymphoma is an increasingly recognised disease entity of aggressive clinical behaviour. The objective of this study was to investigate clinical features and treatment outcomes in patients with nasal-type NK/T cell lymphoma. From January 1991 to December 2003, 26 patients diagnosed as nasal-type NK/T cell lymphoma were included in the analysis. One half of patients presented with poor performance status (ECOG ⩾2); 46% of patients were categorised as high intermediate or high-risk group according to IPI; and 46% of patients were diagnosed at advanced stage. The median survival for 26 patients with nasal-type NK/T cell lymphoma was 7.4 months (95% CI, 0.1, 16.9). The treatment outcome of primary anthracycline-based chemotherapy was poor: 60% CR rate in localised disease and 0% CR rate in advanced disease. After a median follow-up of 24.4 months (range 3.1–99.0) in patients with localised disease who had achieved a CR (range 29.6–165.7), three patients (50.0%) developed disease recurrence at 6.1, 21.8, and 52.1 months, respectively, and all patients presented with locoregional failure. The predictive factors for poor survival were of age greater than 60, advanced stage and poor performance in multivariate analysis. In conclusion, Nasal-type NK/T cell lymphomas showed a poor response to the conventional anthracycline-based chemotherapy, and thus an investigation for an innovative therapy is urgently needed to improve survival in these patients.

Salvage chemotherapy with irinotecan, 5-fluorouracil and leucovorin for taxane- and cisplatin-refractory, metastatic gastric cancer

We performed a phase II study of combination chemotherapy with irinotecan, 5-fluorouracil (5-FU) and leucovorin in metastatic gastric cancer patients who were previously treated with taxane and cisplatin, to evaluate the antitumour activity and toxicity of the combination chemotherapy. The metastatic gastric adenocarcinoma patients who were previously treated with taxane and cisplatin combination as first line, and had at least one measurable lesion, 0-2 ECOG performance status and adequate organ functions, were considered eligible. They received irinotecan (150 mg m(-2), day 1) and leucovorin (100 mg m(-2), day 1), followed by continuous infusion of 5-FU (1000 mg m(-2) day(-1), days 1 and 2) every 2 weeks. Treatment was continued until progression of disease was observed. In all, 64 patients were treated with this combination chemotherapy. The median age of the patients was 55 years (range, 33-74 years), and the median ECOG performance status was 1 (0-1, 61 (95%)). Out of 64 patients, 57 were assessable for response. Among 57 assessable patients, no complete response and 12 partial responses were observed (overall response rate, 21%; 95% confidence interval (CI), 10-32%). Stable disease was observed in 14 patients (25%) and progressive disease in 31 patients (54%). The median time to progression was 2.5 months (95% CI, 1.6-3.4) and the median overall survival since the start of the second-line modified FOLFIRI was 7.6 months (95% CI, 6.5-8.7). Grade 3-4 haematologic toxicities included neutropenia in seven patients (11%) and thrombocytopenia in five patients (8%). Grade 3-4 nonhaematologic toxicities included diarrhoea in two patients (3%) and vomiting in two patients (3%). There were no treatment-related deaths. The combination of irinotecan, 5-FU and leucovorin showed moderate activity and favourable toxicity profile as a second-line treatment in metastatic gastric cancer patients, who were previously treated with taxane and cisplatin.

Lesional location of lateral medullary infarction presenting hiccups (singultus)

BACKGROUND

Hiccups are an infrequent result of lateral medullary infarction. Their importance may be underestimated and they can cause distress, exhaustion, and aspiration. Hiccups in lateral medullary infarction remain poorly understood

OBJECTIVE

To evaluate the relation between the lesional loci of lateral medullary infarction and hiccups.

METHODS

51 patients with lateral medullary infarction were investigated by magnetic resonance imaging within three days of the onset of infarction. Seven of the 51 patients developed hiccup.

RESULTS

All patients with hiccups had middle level lateral medullary lesions, including two with lower level lesions and four with upper level lesions. In the middle level lateral medullary lesions, dorsolateral lesions were most often involved. All patients with lateral medullary infarction presenting with hiccups also had vertigo, dizziness, nausea, vomiting, and dysphagia.

CONCLUSIONS

The observations suggest that middle level and dorsolateral lesion locations in lateral medullary infarction frequently induce hiccups.

Timing of high-risk vascular surgery following coronary artery bypass surgery: A 10-year experience from an academic medical centre

Major non-cardiac surgery within 40 days of coronary angioplasty with stenting has high cardiac complication rates. We have performed a case-control study to determine whether the risk of vascular surgery might have increased in recent survivors of coronary artery bypass surgery (CABG). Using our vascular database from 1990 to 1999, we matched the cases who had vascular surgery within a month of CABG with controls by pre-operative comorbidities of diabetes mellitus, history of myocardial infarction (MI), history of congestive heart failure (CHF), and chronic renal insufficiency and compared the incidence of peri-operative MI, CHF, death, and other complications. Compared to case-matched controls, patients who underwent vascular surgery within a month of CABG suffered significantly greater mortality (20.6% vs. 3.9%, p < 0.005). The incidence of non-fatal cardiac complications was not significantly different between the groups. We conclude that the risk of mortality may be significantly greater in patients undergoing major vascular surgery within a month of CABG.

Effect of epidermal growth factor on preimplantation development and its receptor expression in porcine embryos

The present study aimed to determine the influence of exogenous epidermal growth factor (EGF) on in vitro preimplantation porcine embryo development and its mRNA expression for EGF receptor (EGFR). Oocytes were aspirated from abattoir ovaries, selected and cultured in defined, protein-free media for 44 hr before in vitro fertilization (IVF). Thirty-six hours after IVF, two-cell stage embryos were selected and treated or cultured until embryo treatment. In experiment 1, compact morulae were selected on day 4 after IVF and randomly allocated into 5 groups: NCSU 23 with PVA as group 1; NCSU 23 with PVA and 0.1 ng/ml, 1.0 ng/ml, 10.0 ng/ml EGF as group 2, 3, 4, respectively; NSCU 23 with 0.4% BSA as group 5. In experiment 2, treatment groups were the same as in experiment 1 except that 0.1% crystallized BSA was added to both washing media and all treatment groups instead of PVA. In experiments 3 and 4, two-cell stage embryos were treated and cultured in the same experimental design as experiments 1 and 2, respectively. RT-PCR was used to detect the mRNA expression of EGF receptor in compact morulae and blastocysts. The PCR products were subjected to direct DNA sequencing. There was no significant improvement in the development rate of embryos from compact morulae to blastocysts in the presence of various EGF concentrations (0.1, 1.0, 10.0 ng/ml) versus without EGF addition. They were all significantly lower than those embryos cultured in the continuous presence of 0.4% BSA. However, when a reduced concentration (0.1%) of crystallized BSA was added to all the treatment groups, a significantly lower rate of embryo development was observed in control media (NCSU23 with 0.1% crystallized BSA) compared with those developed in culture media with 0.4% BSA. With the addition of EGF at 10 ng/ml (with 0.1% BSA), embryo development rates were significantly improved over the control group (P < 0.05) and were as good as those rates in 0.4% BSA culture group. When embryos were selected and treated from the 2-cell stage, they did not develop to blastocyst stages after five more days' culture without any protein (BSA) or growth factor addition. When 0.1% BSA was included in the media, blastocyst formation rates were significantly improved by EGF addition at the concentration of both 1.0 or 10 ng/ml (P < 0.05) as compared to 0.0 or 0.1 ng/ml. EGFR mRNA was detected in both compact morulae and blastocyst stages of porcine embryos and confirmed by direct DNA sequencing. Our results indicate that IVM-IVF porcine embryo developmental rates could be improved by the addition of EGF in the culture media with the presence of a reduced amount of defined BSA (>97% albumin). However, EGF alone was not able to elicit any stimulatory effects on embryo development in the absence of protein supplementation. Further studies are needed to investigate the potential synergistic factors in embryo culture media to eventually define the porcine embryo culture media.

Microtubule assembly after treatment of pig oocytes with taxol: correlation with chromosomes, gamma-tubulin, and MAP kinase

In this study, taxol was used as a tool to study the correlation of microtubule assembly with chromosomes, gamma-tubulin and phosphorylated mitogen-activated protein (MAP) kinase in pig oocytes at different maturational stages. Taxol treatment did not affect meiotic resumption and chromosome condensation but inhibited/disrupted chromosome alignment at the metaphase plate and bipolar spindle formation and thus meiotic progression. Microtubules were co-localized with chromosomes and were found to emanate from the chromosomes in taxol-treated oocytes, suggesting that chromosomes may serve as a source of microtubule organization. In addition, the concentric emanation of microtubules within the chromosome-surrounded area in taxol-treated oocytes suggests that microtubule emanation from the chromosomes may be directed by other microtubule-organizing material. The formation of one large spindle or >/=2 spindles in oocytes after taxol removal shows that minus end microtubule-organizing material can be normally located on both sides of chromosomes only when the chromosomes are aligned on the metaphase plate. The co-localization of gamma-tubulin and phosphorylated MAP kinase with microtubule assembly in both control and taxol-treated oocytes suggests that these two proteins are associated microtubule-nucleating material in pig oocytes. However, Western blot analysis showed that neither cytoplasmic microtubule aster formation nor extensive microtubule assembly in the chromosome region induced by taxol was caused by super-activation of MAP kinase. Taxol also induced microtubule assembly depending on chromosome distribution in the first polar body. The results suggest that chromosomes are always co-localized with microtubules and that emanation of microtubules from the chromosomes may be regulated/directed by microtubule-organizing material including gamma-tubulin and phosphorylated MAP kinase in pig oocytes.

Developmental potential of porcine nuclear transfer embryos derived from transgenic fetal fibroblasts infected with the gene for the green fluorescent protein: comparison of different fusion/activation conditions

The in vitro developmental potential of porcine nuclear transfer (NT) embryos was evaluated. Oocytes were matured for 42-44 h, and metaphase II-oocytes were enucleated. Fetal fibroblasts infected with the enhanced green fluorescent protein (EGFP) gene were serum-starved for 3-5 days. A single cell was injected into the perivitelline space of the enucleated oocytes. The reconstructed oocytes were allocated to different fusion and activation conditions. In experiment 1, two different fusion/activation conditions were compared: two pulses of 1.2 kV/cm for 30 microsec (group A), or one pulse of 1.6 kV/cm for 30 microsec followed in 30 min by one pulse of 1.2 kV/cm for 30 microsec (group B). Parthenogenetic controls were created by using the group A parameter. The fusion rate in group A (mean +/- SEM, 68.4% +/- 3.9%) was higher (P < 0.05) than in group B (59.4% +/- 2.3%). The rates of cleavage (50.1% +/- 4.6% to 62.8% +/- 5.5%) were not different among control and treatment groups. However, the rate of parthenogenetic control embryos developing to the blastocyst stage (18.1% +/- 3.1%) was higher (P < 0.05) than the rate of NT embryos (5.9% +/- 1.7% and 4.9% +/- 2.5%). In experiment 2, we compared two pulses of 1.2 kV/cm (group C) versus two pulses of 1.3 kV/cm (group D). For two control groups, the same pulses as those given to group C or D, respectively, were supplied. The fusion rate in group D (70.6% +/- 4.2%) was higher (P < 0.05) than in group C (58.9% +/- 2.7%). The cleavage rates were not different among control and treatment groups (58.1% +/- 8.1% to 73.6% +/- 6.0%). However, the rate of embryos developing to the blastocyst stage in group D (3.5% +/- 1.7%) was lower (P < 0.05) than in controls and group C (11.4% +/- 2.0% to 16.4% +/- 1.1%). In experiment 3, we examined whether the presence of cytochalasin B (CB) during donor cell injection affects the development of NT embryos. The fusion rate of oocytes in the group with CB (78.4% +/- 1.4%) was higher (P < 0.05) than in the group without CB (70.9% +/- 0.2%). The cleavage rate of the control group (85.5% +/- 4.9%) was higher (P < 0.05) than those of the treatment groups (61.6% +/- 2.7% and 63.9% +/- 4.3%). However, the rates of embryos developing to the blastocyst stage (8.1% +/- 2.5% to 19.1% +/- 6.0%) and the mean cell number of blastocysts (29.4 +/- 5.2 to 45.7 +/- 6.4) were not different among control and treatment groups. Green fluorescence was observed at all stages in NT embryos. These results indicate that two pulses of 1.2 kV/cm are enough for fusion/activation of NT embryos to develop to the blastocyst stage, and that the presence of CB during donor cell injection is not necessary for early development of NT embryos.

Feasibility of producing porcine nuclear transfer embryos by using G2/M-stage fetal fibroblasts as donors

The type of donor cell most suitable for producing cloned animals is one of the topics under debate in the field of nuclear transfer. To provide useful information to answer this question, G2/M- and G0/G1-stage fetal fibroblasts were used as donor cells for nuclear transfer. In vitro-matured oocytes derived from abattoir ovaries were used as recipient cytoplasts. In both groups, nuclear envelope breakdown and premature chromosome condensation were completed within 1-2 h after donor cells were injected into the cytoplasm of oocytes. Microtubules were organized around condensed chromosomes and formed a spindle within 1-1.5 h after activation. Decondensation of chromosomes could be seen within 2-4 h after activation. Reformation of the new nuclear envelope occurred 4-6 h after activation and was followed by nuclear swelling and formation of a pronucleus-like structure (PN) 8-12 h after activation. Most (80.6%) of the reconstructed oocytes derived from G2/M cells extruded polar body-like structures (PB). However, a much lower frequency of PB (21.7%) was observed in the reconstructed oocytes derived from G0/G1 donors. A variety of PN and PB combinations were observed in reconstructed oocytes derived from G2/M-stage donors, including 1PN+0PB, 1PN+1PB, 1PN+2PB, 2PN+0PB, 2PN+1PB, 2PN+2PB, and 3PN+1PB. Chromosomes of most embryos (10/13) derived from G2/M stage were diploid. The percentage of cleavage and blastocysts and the average nuclear number of blastocysts in the G2/M and G0/G1 groups were not different. These results demonstrate that the G2/M stage can be morphologically remodeled by cytoplasm of MII oocytes in pigs. To maintain normal ploidy, the extra chromosomes derived from G2/M-stage cells could be expelled by oocytes as a second polar body. G2/M-stage fibroblast nuclei could direct reconstructed embryos to develop to the blastocyst stage.

Production of nuclear transfer-derived swine that express the enhanced green fluorescent protein

The ability to add or delete specific genes in swine will likely provide considerable benefits not just to agriculture but also to medicine, where pigs have potential as models for human disease and as organ donors. Here we have transferred nuclei from a genetically modified fibroblast cell line to porcine oocytes, matured in vitro under defined culture conditions, to create piglets expressing enhanced green fluorescent protein. The nuclear transfer-derived piglets were of normal size, although some mild symptoms of "large offspring syndrome" were evident. These experiments represent a next step towards creating swine with more useful genetic modifications.

Transgenic pigs produced using in vitro matured oocytes infected with a retroviral vector

Here we report the production of transgenic pigs that express enhanced green fluorescent protein (eGFP). Porcine oocytes were matured in vitro in a serum-free, chemically defined maturation medium, subsequently infected with a replication deficient pseudotyped retrovirus, fertilized and cultured in vitro before being transferred to a recipient female. Two litters were born from these embryo transfers; one pig from each litter was identified as transgenic and both expressed eGFP. From a tool in basic research to direct applications in production agriculture, domestic livestock capable of expressing foreign genes have many scientific applications.

Development of porcine embryos and offspring after intracytoplasmic sperm injection with liposome transfected or non-transfected sperm into in vitro matured oocytes

The objective of this study was to evaluate in vitro and in vivo development of porcine in vitro matured (IVM) porcine oocytes fertilised by intracytoplasmic sperm injection (ICSI) and the possibility of producing transgenic embryos and offspring with this procedure. Activated ICSI oocytes had a higher pronuclear formation than non-activated ICSI oocytes (mean 64.8+/-17.3% vs 28.5+/-3.4%, p<0.05). When the zygotes with two pronuclei were cultured to day 2, there was no difference (p<0.05) in the cleavage rate (mean 60.0+/-7.0% vs 63.3+/-12.7%) between the two groups. The blastocyst rate in the activation group was significantly higher than that in the non-activation group (mean 30.0+/-11.6% vs 4.6+/-4.2%, p<0.05). After injection of the sperm transfected with DNA/liposome complex, destabilised enhanced green fluorescent protein (d2EGFP) expression was not observed on day 2 in either cleaved or uncleaved embryos. But from day 3, some of the embryos at the 2-cell to 4-cell stage started to express d2EGFP. On day 7, about 30% of cleaved embryos, which were in the range of 2-cell to blastocyst stage, expressed d2EGFP. However, for the IVF oocytes inseminated with sperm transfected with DNA/liposome complex, and for oocytes injected with sperm transfected with DNA/liposome complex, and for oocytes injected with DNA/liposome complex following insemination with sperm not treated with DNA/liposome complex, none of the embryos expressed d2EGFP. Sixteen day 4 ICSI embryos derived from sperm not treated with DNA/liposome complex were transferred into a day 3 recipient. One recipient delivered a female piglet with normal birthweight. After transfer of the ICSI embryos derived from sperm transfected with DNA/liposome complex, none of the four recipients maintained pregnancy.