The hypocretin neurotransmission system in myotonic dystrophy type 1

BACKGROUND

Patients with myotonic dystrophy type 1 (DM1) frequently have symptoms of excessive daytime sleepiness (EDS). Some patients with DM1 show sleep-onset REM, similar to that observed in narcolepsy. Narcolepsy is characterized by impaired hypocretin (Hcrt) neurotransmission.

OBJECTIVE

To test for dysregulation of Hcrt neurotransmission in a prospective cohort of patients with DM1.

METHODS

Hcrt levels in CSF were measured by radioimmunoassay. Sleep physiology was assessed by overnight polysomnography (PSG) and a multiple sleep latency test (MSLT). Splicing of Hcrt receptor 1 and 2 (HcrtR1 and HcrtR2) mRNA was examined in postmortem samples of temporal cortex.

RESULTS

Seventeen of 38 patients with DM1 reported symptoms of EDS. Among patients with DM1 with EDS who underwent PSG/MSLT, 7 of 13 showed reduced sleep latency, sleep-onset REM, or both. However, CSF Hcrt levels in DM1 (mean 277 pg/mL, n = 38) were not different from controls (mean 277 pg/mL, n = 33). Also, splicing of HcrtR1 and HcrtR2 mRNA in patients with DM1 was similar to controls.

CONCLUSIONS

Excessive daytime sleepiness and dysregulation of REM sleep occur frequently in patients with myotonic dystrophy type 1 (DM1). However, the pathophysiologic basis is distinct from narcolepsy, as patients with DM1 do not have a consistent defect of Hcrt release or receptor splicing.

Suppression of early experimental osteoarthritis by in vivo delivery of the adenoviral vector-mediated NF-kappaBp65-specific siRNA

OBJECTIVE

This study was to use adenoviral vector-mediated nuclear factor-kappaBp65 (NF-kappaBp65)-specific siRNA (Ad-siRNA(NF-kappaBp65)) to suppress the progression of early osteoarthritis (OA) in rat model, and therefore to explore a new gene therapy for OA.

METHODS

Reverse transcription polymerase chain reaction was performed to confirm the silencing effect of Ad-siRNA(NF-kappaBp65) in cultured rat chondrocytes. Transection of the medial collateral ligament plus partial medial meniscectomy was operated in the knee of rats to establish OA model. Histological analysis was made to assess the morphological change of cartilage and synovium, and enzyme-linked immunosorbent assay was made to measure the expression of cytokines, such as interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), in synovial fluid. The silencing effect of Ad-siRNA(NF-kappaBp65) on NF-kappaBp65 in cartilage and synovium of knee was measured with Western blot and the activation of NF-kappaB was measured with electrophoretic mobility shift assays.

RESULTS

Ad-siRNA(NF-kappaBp65) can inhibit the activation of NF-kappaB and the expression of NF-kappaBp65 in cartilage and synovium of the knee, restrain the induction of IL-1beta and TNF-alpha in synovial fluid, alleviate the inflammation of synovium and reduce the degradation of cartilage in early phase of experimental OA.

CONCLUSIONS

Ad-siRNA(NF-kappaBp65) can suppress the progression of the early experimental OA which suggests that Ad-siRNA(NF-kappaBp65) has potential to be a useful preventive and therapeutic agent for OA.

81 INDUCED BLASTOCOEL COLLAPSE IMPROVES SURVIVAL RATES OF PORCINE BLASTOCYSTS AFTER VITRIFICATION

Cryopreservation of porcine blastocysts is regarded as a demanding task because of the high chilling sensitivity and low survival rates. Ultrarapid vitrification techniques combined with the previous artificial induction of collapse of the blastocoel have been successfully applied in mouse and human. The purpose of our work was to use the Cryotop (Kitasato Supply Co., Tokyo, Japan) vitrification method combined with induced blastocyst collapse for cryopreservation of porcine blastocysts produced with parthenogenetic activation of in vitro-matured oocytes. A total of 1200 slaughterhouse-derived porcine oocytes were matured for 41–42 h. Zona-intact or zona-free oocytes (after pronase digestion) were activated with a single electric impulse of 63 or 43 V cm–1, respectively, and incubated in 5 μg mL–1 cytochalasin B and 10 μg mL–1 cycloheximide for 4 h (Du et al. 2007 Cryobiology 54, 181–187). Embryo culture was performed in PZM-3 medium (Yoshioka et al. 2002 Biol. Reprod. 66, 112–119) in 5% CO2, 5% O2, and 90% N2 and maximum humidity. On Day 6, collapse was induced manually in approximately half of the blastocysts with the use of a fire-polished holding pipette and injection pipette (Cook Australia, Brisbane, Queensland, Australia). Ten min after the manipulation, collapsed and control (not manipulated) blastocysts were vitrified with the Cryotop, and then warmed and diluted in 1, 0.5, and 0 m sucrose, respectively (Kuwayama et al. 2005, Reprod. BioMed. Online 11, 300–308). Reexpansion of blastocysts was evaluated under a stereomicroscope after 16–18 h of culture under conditions described above. SPSS 11.0 program (SPSS, Inc., Chicago, IL, USA) was used for statistical calculations; values with P < 0.05 were regarded as significant. Reexpansion rates of blastocysts are shown in Table 1. Our results indicate that manually induced collapse of the blastocoel increases reexpansion rates of both zona-intact and zona-free porcine blastocysts after Cryotop vitrification. The combination of these simple techniques may help to improve the efficiency of cryopreservation of pig embryos for both experimental and practical applications. Table 1. Reexpansion rates after vitrification of blastocysts with or without induced blastocoel collapse The authors thank Ruth Kristensen, Anette Pedersen, Janne Adamsen, and ClausWillemoes for their help and excellent technical assistance.

303 ESTABLISHMENT OF PREGNANCIES WITH HANDMADE CLONING PORCINE EMBRYOS RECONSTRUCTED WITH FIBROBLASTS CONTAINING AN ALZHEIMER'S DISEASE GENE

Somatic cell nuclear transfer (SCNT) offers the possibility of pig transgenesis. Importantly, specific genetic manipulations can be performed in donor cells before SCNT to derive pig models for specific human genetic diseases, including the neurodegenerative disorder Alzheimer's disease (AD). In the present study, we established pregnancies after transfer of SCNT blastocysts produced by the handmade cloning (HMC) technique. The blastocysts were transgenic for a human gene, amyloid precursor protein gene with the 'Swedish mutation' (APPsw), causing AD. For transgenesis, minipig fibroblasts were transfected by lipofection with a vector containing the APPsw gene under control of the platelet-derived growth factor β promoter (PDGF-APPsw) and a neomycin-resistance selection gene. Neomycin-resistant colonies were isolated, expanded, analyzed, and used for HMC. Cumulus–oocyte complexes were aspirated from ovaries of slaughtered sows and matured for 41 h. Subsequently, the cumulus cells were removed in hyaluronidase, and zonae pellucidae were partially digested by incubation in pronase. Oocytes with a visible polar body (PB) were subjected to oriented bisection. Less than half of the cytoplasm adjacent to the PB was removed with a microblade. The cytoplasts were used as recipients for embryo reconstruction. Reconstructed embryos were produced by a 2-step fusion procedure. At the first step, 1 cytoplast was fused with 1 fibroblast in the absence of Ca2+. After 1 h, the cytoplast-fibroblast pair and another cytoplast were fused and activated simultaneously in the presence of Ca2+, incubated in cytochalasin B and cycloheximide for 4 h, and then cultured in PZM-3 medium. The development of reconstructed embryos to the blastocysts stage was determined after 5, 6, or 7 days of in vitro culture. To investigate the in vivo developmental capacity, blastocysts were transferred surgically to synchronized recipients. When using PDGF-APPsw-transgenic minipig fibroblasts, the rate of blastocyst formation (mean � SEM) was 39 � 3% (164/424). In comparison, non-transgenic fibroblasts resulted in a blastocyst development of 36 � 7% (36/102). In 4 recipients that received an average of 54 Day 5, 6, and 7 PDGF-APPsw-transgenic blastocysts, 2 ongoing pregnancies were confirmed by ultrasonography, 1 pregnancy was lost, and 1 returned to estrus. The results show a high in vivo developmental competence of blastocysts produced after SCNT of PDGF-APPsw-transgenic minipig fibroblasts.

28 HIGH HYDROSTATIC PRESSURE IMPROVED DEVELOPMENTAL COMPETENCE OF PORCINE OOCYTES FOR HANDMADE CLONING

High hydrostatic pressure (HHP) has been introduced into the field of embryology recently, with the possible mechanism that a sublethal HHP could induce the synthesis of molecular chaperons to protect the embryos from further stresses. Improved cryotolerance has been achieved successfully in HHP-treated mouse (Pribenszky 2005 Anim. Reprod. Sci. 87, 143–150) and bovine (Pribenszky 2005 Reprod. Domest. Anim. 40, 338) embryos, and the semen of bull (Pribenszky 2007 Reprod. Fertil. Dev. 19, 181–182) and boar (Pribenszky 2005 Reprod. Fertil. Dev. 18, 162–163). The objective of the present study was to apply this new technique to in vitro-matured (IVM) porcine oocytes and further investigate its effect in the procedure of handmade cloning (HMC). After 40 h IVM, cumulus–oocyte complexes (COCs) were loaded in 0.5-mL straws by a 2-mL syringe, with HEPES-buffered TCM199 as the loading medium. COCs were then treated with 20 MPa (200 times greater than atmospheric pressure) for 60 min by a pressurizing device (Cryo-Innovation Inc., Budapest, Hungary), with an interval of 120 min between HHP treatment and subsequent HMC. Two different cell lines (from Day 40 fetuses of Yucatan and Danish Landrace breeds (LW1-2)) were used as donor cells for nuclear transfer. A total of 592 reconstructed embryos were produced from both HHP-treated and control groups and were in vitro cultured for 6 days to evaluate the developmental competence through to blastocyst formation. The effect of donor cells on blastocyst development was also investigated. SPSS 11.0 program (SPSS, Inc., Chicago, IL, USA) was used for statistical analysis; values with P < 0.05 were regarded as significant. Blastocyst rates of the different groups are shown in Table 1. Our results indicated that COCs treated with HHP had a much higher blastocyst rate than those untreated (P < 0.01) and this improvement was not affected by using different donor cells for nuclear transfer. In conclusion, the sublethal HHP treatment could improve the in vitro developmental competence of porcine IVM oocytes when they are used for HMC. Further in vivo experiments are required to investigate the long-term effect of HHP on embryo development. Table 1. Day 6 blastocyst rates of HHP-treated and control groups with different donor cells for nuclear transfer The authors thank Ruth Kristensen and Janne Adamsen for their help and excellent technical assistance.

Isolated oesophageal cyst connected with the bronchus

We report an unusual case of a patient with an oesophageal cyst connected to the bronchus. A 24-year old male with a two-year history of repeated attacks of chest infection and haemoptysis was found to have a cyst of 4 x 4 cm affecting the anterior and apical segments of the right upper lobe. The cyst was excised in its entirety and the histopathological study of the cyst showed stratified squamous epithelium with submucosal and muscular layer but no cartilage. The pathological diagnosis was an oesophageal cyst. No previous case of isolated oesophageal cyst connected to the bronchus has been reported according to the available literature.

Presentation of hemiplegic migraine--hemiplegia and hemi-sensory loss following general anaesthesia

We report a case of a 15-year-old male who developed severe left-sided hemiplegia and hemi-sensory loss 20 minutes after arrival in post anaesthetic care unit following an uneventful general anaesthesia for removal of a cannulated screw of left hip. Initial CT and MRI/MRA with diffusion-weighted imaging were unremarkable. The patient was transferred to The Royal Children's Hospital Melbourne and was commenced on heparin infusion pending investigation results. Complete recovery occurred within 36 hours. Eventually, hemiplegic migraine was diagnosed on the basis of negative investigations and a retrospective history of the patient's migraine. This case demonstrates that the management of peri-operative neurological deficits must be approached in a systematic fashion. Hemiplegic migraine is a well-defined clinical syndrome. It is not merely a diagnosis of exclusion.

Comparative study on effect of different promoters on expression of cry1Ac in Bacillus thuringiensis chromosome

AIMS

The aim of this work was to investigate the effect of cry3A promoter on the expression of cry1Ac in Bacillus thuringiensis chromosome and stably enhance the production of different cry genes under the control of cry3A promoter.

METHODS AND RESULTS

The cry1Ac gene, which is specific to Lepidopteran larvae, was integrated into the chromosome of a B. thuringiensis plasmid-free and acrystalliferous strain BMB171, under the control of cry3A promoter and cry1Ac promoter, respectively. The expression of cry1Ac genes in the chromosome of host strain was investigated. The results from sodium dodecyl sulfate-polyacrymide gel electrophoresis, crystal observation and bioassay showed that either integrated with cry3A promoter (cry3Apro-cry1Ac) or with its native promoter (cry1Acpro-cry1Ac), cry1Ac gene could efficiently and stably express in the chromosome. The production of cry3Apro-cry1Ac gene was higher than that of cry1Acpro-cry1Ac gene.

CONCLUSIONS

The cry3A promoter enhanced the expression of cry1Ac gene efficiently either on the chromosome or on the plasmid in B. thuringiensis strain.

SIGNIFICANCE AND IMPACT OF THE STUDY

So far, the comparative studies on cry3A promoter and other cry promoters were carried on B. thuringiensis plasmids. This system offers an additional method for potentially improving the efficacy of B. thuringiensis insecticidal proteins efficiently, stably and safely.

The development of hypocretin (orexin) deficiency in hypocretin/ataxin-3 transgenic rats

Narcolepsy is linked to a widespread loss of neurons containing the neuropeptide hypocretin (HCRT), also named orexin. A transgenic (TG) rat model has been developed to mimic the neuronal loss found in narcoleptic humans. In these rats, HCRT neurons gradually die as a result of the expression of a poly-glutamine repeat under the control of the HCRT promoter. To better characterize the changes in HCRT-1 levels in response to the gradual HCRT neuronal loss cerebrospinal fluid (CSF) HCRT-1 levels were measured in various age groups (2-82 weeks) of wild-type (WT) and TG Sprague-Dawley rats. TG rats showed a sharp decline in CSF HCRT-1 level at week 4 with levels remaining consistently low (26%+/-9%, mean+/-S.D.) thereafter compared with WT rats. In TG rats, HCRT-1 levels were dramatically lower in target regions such as the cortex and brainstem (100-fold), indicating decreased HCRT-1 levels at terminals. In TG rats, CSF HCRT-1 levels significantly increased in response to 6 h of prolonged waking, indicating that the remaining HCRT neurons can be stimulated to release more neuropeptide. Rapid eye movement (REM) sleep in TG rats (n=5) was consistent with a HCRT deficiency. In TG rats HCRT immunoreactive (HCRT-ir) neurons were present in the lateral hypothalamus (LH), even in old rats (24 months) but some HCRT-ir somata were in various stages of disintegration. The low output of these neurons is consistent with a widespread dysfunction of these neurons, and establishes this model as a tool to investigate the consequences of partial hypocretin deficiency.

Near absence of IL-15R-alpha T-cells in EBV-associated Hodgkin lymphoma patients

8087

Background: Epstein-Barr virus (EBV) (+) Hodgkin's lymphoma (HL) has been linked to acute infectious mononucleosis (AIM). EBV-associated AIM was recently reported (Sauce et al, Blood 2006, 108: 11) to be associated with a long lasting immunologic scar (near complete absence of IL-15 receptor alpha (IL-15Ra expression on T cells in peripheral blood mononuclear cells (PBMC)). We sought to confirm the scar observation and to determine whether such a scar might also be characteristic of EBV (+) HL patients. Methods: PBMCs from 5 donors with history of AIM (3 months to 4 years before), 10 EBV-seropositive donors without history of AIM, 10 EBV-seronegative donors, 22 HL patients with EBV (+) tumors and 29 HL patients with EBV (-) tumors were assayed to determine IL-15Ra expression on CD3/CD8+ cells using a FACScalibur flow cytometer. Results: IL-15Ra expression in healthy donors with history of AIM [mean: 2.9% (1.5–6.5%)] was much lower than in those without history of AIM [mean: 83% (65–98%)] (p = 0.001). Expression did not differ between healthy EBV-seropositive donors without history of AIM [mean: 82% (65–95%)] and healthy EBV-seronegative donors [mean: 89% (82–98%)] (p = 0.32). Expression was markedly different between EBV (-) HL [mean: 82% (72–99%)] and EBV (+) HL patients [mean: 3.2% (1.1–7.1%)] [p = 0.001, 95% CI(10.3–32.1)]. No difference was found when age, time blood was drawn (pre or post-treatment), disease stage and histological subtype were compared. This IL- 15Ra deficit was seen in patients before and more than one year after standard therapy. Conclusions: This study confirms the virtual absence of IL-15Ra expression in lymphocytes from patients with history of AIM. That observation is now extended to include patients with EBV (+) HL at presentation and in remission. Whether this deficit contributes to the pathogenesis of EBV (+) associated HL remains to be determined.

No significant financial relationships to disclose.

Unusually high rates of hypersensitivity to cetuximab in the middle-southern United States: Association with atopic phenotype

9051

Purpose: To confirm the anecdotal observation that pts in North Carolina (NC) and Tennessee (TN) treated with cetuximab (C-mab) experience hypersensitivity reactions (HSR) at a much higher rate than that reported nationally and internationally (= 3%). Methods: Data from pts treated with C-mab on clinical trials (CTs, n = 88) at 3 research sites in TN and NC were analyzed for grade 3 or 4 HSR. Additional information was obtained from medical records under IRB approval at the University of North Carolina (UNC) for 90 pts (including 35 pts on CTs) to determine whether history of other significant allergy was a risk factor for HSR. Prior allergy was defined as history of H1 antagonist use, or notation in the medical record of significant drug allergy (excluding narcotic allergies), bee sting allergy, eczema, allergic reactive airways disease, or food allergy. Pearson's or Fisher's exact tests were used for comparison of proportions. Results: Data for 88 pts on CTs and an additional 55 pts treated outside of CTs was included in this analysis. Pts had a variety of tumor types, the most frequent being colorectal and lung For the CT group (n = 88), the overall rate of grade 3 to 4 HSR was 21.6%, significantly higher than the rate noted in any large published trial (p < 0.0001 for comparison to data from Cunningham et al). All HSRs occurred during the first dose. There was no apparent protection from HSR afforded by premedication with dexamethasone in either the CT cohort or the overall UNC cohort. Upon examination of medical records of 90 pts treated at UNC (14.4% gr 3/4 HSR overall), there was a strong relationship between prior allergy history and chance of HSR; 10/28 pts with any HSR vs. 7/62 without allergy history (p = 0.006), and grade 3/4 HSR occurred in 8/28 versus 5/62, respectively (p = 0.01). Conclusions: At the sites in neighboring Southern US states studied, HSR was far more common than reported in national studies. History of prior allergy is a strong predictor of HSR, although is not specific enough to be used as the sole means of excluding pts from therapy. Further investigation of more specific predictors of HSR in the US Middle South is warranted, and pts being treated with C-mab in the region should be observed particularly closely during their first infusion.

No significant financial relationships to disclose.

Sentinel lymph node micrometastasis detection using immunohistochemistry and reverse transcription-polymerase chain reaction for cytokeratin 19 in breast cancer

11074

Background: In breast cancer, the sentinel lymph node (SLN) can be used to assess the axillary nodal status to guide the axillary surgery, tumor staging and adjuvant systematic therapy. Histology and immunohistochemistry (IHC) are currently the routine methods of SLN assay. The facts that about 30% of node-negative breast cancer patients relapse within five years and that micrometastasis were found in 9%∼30% negative lymph nodes when they were re-examined using serial sectioning suggest that current histological detection methods are inadequate for identifying metastatic tumor cells in lymph nodes. The primary objective of this study was to develop an assay by using a combination of reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry for cytokeratin 19 (KT19) expression in SLN. Methods:139 SLN samples were collected from 139 breast cancer patients undergoing SLN biopsy using Isosulfan Blue dye during modified mastectomy between June 2002 and June 2005. The SLNs were dissected into two parts, half were frozen in liquid nitrogen during sugery for RT-PCR detection and another half were kept in liquor formaldehyde for routine hematoxylin-eosin (H&E) examination and IHC detection. In 62 tumor-negative SLNs at routine H&E examination (pN0), we performed IHC and RT-PCR for KT19. Results: Of the 62 tumor-negative SLNs at routine H&E examination, 11% (7/62) were positive on extensive IHC analyses for KT-19, which were all positively identified by RT-PCR assay. Six SLNs (10%) were negative for micrometastases (with H&E and IHC for KT-19) but RT-PCR positive. There was asignificant difference in detective rate between these two methods statistically (χ2 = 4.1667 , P = 0.0412) and the coincidence were high ( kappa = 0.6483) Conclusions: As IHC analysis resulted in a 11% detection rate in H&E negative SLNs, IHC is essential to avoid false- negative SLN micrometastases. Molecular analysis with KT19 allows detection of breast cancer micrometastases with an additional 10% detection rate in H&E negative SLNs and resulted in a high coincidence with IHC analysis. However, the clinical value of these histologically negative but RT-PCR positive SLNs can only be determined with long term follow up.

No significant financial relationships to disclose.

Effects of endothelin-11-31 on cell viability and [Ca2+]i in cultured neonatal rat cardiomyocytes

We previously found that endothelin-1(1-31) (ET-1(1-31)) exhibited a pro-arrhythmogenic effect in isolated rat hearts. In this study, we further investigated the effects of ET-1(1-31) on a cell viability and observed [Ca(2+)](i) in cultured cardiomyocytes. Cultured neonatal rat cardiomyocytes were treated with 0.1, 1, and 10 nM ET-1(1-31) for 24h in the presence or absence of ET(A) receptor antagonist (BQ(123)) or phosphoramidon, a NEP/ECE inhibitor. Cell injury was evaluated by supernatant lactate dehydrogenase (LDH) assay, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) content. Cell viability was assessed by MTT assay. [Ca(2+)](i) was measured with Fluo-3/AM under a laser confocal microscope. 1) ET-1(1-31) dose-dependently increased LDH release and decreased cell viability. 2) LDH and MDA levels were significantly elevated and SOD activity decreased after administration of 1 nM ET-1(1-31) for 24h, and these changes were markedly attenuated by 1 uM BQ(123). 3) Exposure to 10 nM ET 1(1-31) caused a continuous increase in [Ca(2+)](i) to cultured beating cardiomyocytes and termination of [Ca(2+)](i) transient within 6 min, and this change was reversed by 1 uM BQ(123) and attenuated by 0.5 mM phosphoramidon. These results suggest that ET-1(1-31) could cause cell injury, and that the effect of ET-1(1-31) on [Ca(2+)](i) transients is mainly mediated by ET(A) receptor and partially attributed to the conversion of ET-1(1-31) to ET-1(1-21).