Development of a risk-ranking framework to evaluate potential high-threat microorganisms, toxins, and chemicals in food

Through a cooperative agreement with the U.S. Food and Drug Administration, the Institute of Food Technologists developed a risk-ranking framework prototype to enable comparison of microbiological and chemical hazards in foods and to assist policy makers, risk managers, risk analysts, and others in determining the relative public health impact of specific hazard-food combinations. The prototype is a bottom-up system based on assumptions that incorporate expert opinion/insight with a number of exposure and hazard-related risk criteria variables, which are propagated forward with food intake data to produce risk-ranking determinations. The prototype produces a semi-quantitative comparative assessment of food safety hazards and the impacts of hazard control measures. For a specific hazard-food combination the prototype can produce a single metric: a final risk value expressed as annual pseudo-disability adjusted life years (pDALY). The pDALY is a harmonization of the very different dose-response relationships observed for chemicals and microbes. The prototype was developed on 2 platforms, a web-based user interface and an Analytica(R) model (Lumina Decision Systems, Los Gatos, Calif., U.S.A.). Comprising visual basic language, the web-based platform facilitates data input and allows use concurrently from multiple locations. The Analytica model facilitates visualization of the logic flow, interrelationship of input and output variables, and calculations/algorithms comprising the prototype. A variety of sortable risk-ranking reports and summary information can be generated for hazard-food pairs, showing hazard and dose-response assumptions and data, per capita consumption by population group, and annual p-DALY.

Pituitary adenylate cyclase-activating polypeptide directly stimulates LH and FSH secretion by human pituitary gonadotrophinomas

The effect of pituitary adenylate cyclase-activating polypeptide (PACAP) on LH and FSH secretion by human pituitary gonadotrophinomas in cell culture was studied. PACAP (1-38 peptide, 0.2-20 nmol/L) dose-dependently stimulated both LH and FSH secretion after 24 hours incubation. Of 11 tumours studied, PACAP (20 nmol/L) stimulated LH and/or FSH secretion by 1.7-4 fold in 9 cases. Two tumours did not respond to PACAP, although LHRH was stimulatory in these. None of the 11 tumours contained gsp mutations, excluding the possibility that these were the cause of the occassionally observed non-responsiveness to PACAP. A combination of PACAP (20 nmol/L) together with TRH (25 nmol/L) resulted in greater stimulatory effects on LH and FSH secretion than exerted by either peptide alone, but this was not observed with LHRH. In 3 tumours tested, PACAP stimulated cAMP production 2-3 fold by cultured human pituitary gonadotrophinomas but had no effect on rate of phosphatidylinositol (PI) turnover. These results indicate that PACAP can directly stimulate LH and FSH secretion by human pituitary gonadotrophs and that PACAP-receptors in gonadotrophin-secreting tumours are coupled with adenylate cyclase but not the PI second messenger system. We conclude that PACAP may play a role in controlling gonadotroph function in the human pituitary gland.

Treatment of hypercholesterolaemia and hypertriglyceridaemia with magnesium

A daily intake of 3 g magnesium (as magnesium oxide) for six weeks had no effect on serum cholesterol and serum triglyceride in 17 patients suffering from hypercholesterolaemia and/or hypertriglyceridaemia.

Meat juice: An alternative matrix for assessing animal health by measuring acute phase proteins. Correlations of pig-MAP and haptoglobin concentrations in pig meat juice and plasma

Quantification of acute phase proteins (APPs) in blood can be used for monitoring animal health and welfare on farms, and could be also of interest for the detection of diseased animals during the meat inspection process. However serum or plasma is not always available for end-point analysis at slaughter. Meat juice might provide an adequate, alternative matrix that can be easily obtained for post-mortem analysis at abattoirs. The concentrations of pig Major Acute phase Protein (pig-MAP) and haptoglobin, two of the main APPs in pigs, were determined in approximately 300 paired samples of plasma and meat juice from the diaphragm (pars costalis), obtained after freezing and thawing the muscle. APPs concentrations in meat juice were closely correlated to those in plasma (r=0.695 for haptoglobin, r=0.858 for pig-MAP, p<0.001). These results open new possibilities for the assessment of animal health in pig production, with implications for food safety and meat quality.

306 GENERATION AND CHARACTERIZATION OF HUMAN A20 TRANSGENIC PIGS BY SOMATIC CELL NUCLEAR TRANSFER

Xenotransplantation is considered a solution to diminish the acute shortage of human organs. Although the hyperacute rejection occurring instantly after xenotransplantation can already be reliably controlled, the following immunological defense like the acute vascular rejection (AVR) remains a major hurdle for long-term survival of xenografts in porcine-to-primate organ transplantation. AVR is primarily characterized by endothelial cell activation with severe consequences on coagulation. The human A20 (hA20) gene exhibits antiapoptotic and anti-inflammatory properties in endothelial cells (Ferran C 2006 Transplantation 82, 36–40) and could thus prevent endothelial cell activation leading to AVR and xenograft destruction. Here, hA20-transgenic pigs were produced by somatic cell nuclear transfer (SCNT) in order to examine the ability of hA20-expressing tissues and organs to modulate the AVR. Two hA20-expression vectors, containing the promoters CAGGS or EF1-α in addition to a neomycin resistance cassette, were transfected into porcine fetal fibroblasts. Transfection was accomplished by electroporation, and the cell clones were selected with G418 (800 μg mL–1) for 14 days. Resistant cell clones were screened in PCR with hA20-specific primers. SCNT was performed as previously described (Hölker M et al. 2005 Cloning Stem Cells 7, 35–44). After 8 SCNT sessions with pCAGGSEhA20-transgenic cell clones, embryo transfer was carried out to 16 peripuberal recipients resulting in 12 pregnancies (75%). Sixteen fetuses were isolated after sacrificing the recipient sows, and 45 piglets were born. Six of 16 fetuses (37.5%) and 15 of 45 (33.3%) piglets were transgenic. Four SCNT sessions were completed with pEF1hA20-transgenic cell clones following embryo transfer to 6 sows and 5 pregnancies were established (83.3%). Five fetuses were isolated and 14 piglets born. Five of 5 fetuses (100%) and 9 of 14 (64.3%) piglets were transgenic. Expression analysis (RT-PCR and Northern blots) showed transcription of the hA20 gene in heart, muscle, and cultivated porcine aortic endothelial cells of the pCAGGSEhA20-transgenic animals. No transcription was detected in pEF1hA20-transgenic animals. Current results show that hA20-transgenic pigs develop physiologically compared to wildtype counterparts. Expressing tissues and organs were only found in pCAGGSEhA20-transgenic animals, which are now being tested regarding functionality of the hA20 transgene. We would like to thank Prof. Beyaert from the University of Ghent, Belgium, for providing us with the A20-expression vector pCAGGSEhA20.

Myoclonus-dystonia: significance of large SGCE deletions

Myoclonus-dystonia (M-D) is an autosomal-dominant movement disorder caused by mutations in SGCE. We investigated the frequency and type of SGCE mutations with emphasis on gene dosage alterations and explored the associated phenotypes. We tested 35 M-D index patients by multiplex ligation-dependent probe amplification (MLPA) and genomic sequencing. Mutations were found in 26% (9/35) of the cases, all but three with definite M-D. Two heterozygous deletions of the entire SGCE gene and flanking DNA and a heterozygous deletion of exon 2 only were detected, accounting for 33% (3/9) of the mutations found. Both large deletions contained COL1A2 and were additionally associated with joint problems. Further, we discovered one novel small deletion (c.771_772delAT, p.C258X) and four recurrent point mutations (c.289C>T, p.R97X; c.304C>T, p.R102X; c.709C>T, p.R237X; c.1114C>T, p.R372X). A Medline search identified 22 articles on SGCE mutational screening. Sixty-four unrelated M-D patients were described with 41 different mutations. No genotype-phenotype association was found, except in patients with deletions encompassing additional genes. In conclusion, a rigorous clinical preselection of patients and careful accounting for non-motor signs should precede mutational tests. Gene dosage studies should be included in routine SGCE genetic testing.

306 GENERATION OF HUMAN A20 GENE-TRANSGENIC PORCINE FETAL FIBROBLASTS FOR SOMATIC CELL NUCLEAR TRANSFER

The aim of this project was to produce transgenic pigs with improved features in xenotransplantation, by expressing the human A20 gene to modulate the acute vascular rejection (AVR) reaction ocurring after porcine-to-human xenotransplantation. The A20 gene was originally characterized as a tumor necrosis factor-inducible gene in human umbilical vein endothelial cells (Opipari AW et al. 1990 J. Biol. Chem. 25, 14 705–14 708). The gene is both anti-apoptotic and anti-inflammatory in endothelial cells (Ferran C 2006 Transplantation 82(1 Suppl.), S36–S40) and could thus prevent endothelial cell activation leading to AVR. The hA20-expression vector driven by the CAGGS hybrid promoter (chicken β-actin–rabbit β-globin) containing an IRES-neomycin resistance cassette (9.1 kb) was transfected into porcine fetal fibroblasts (PFF) derived from German Landrace porcine fetal explant cultures. Transfection of 3 � 106 cells was accomplished at 450 V and 350 µF with 10 µg of plasmid DNA. Then, G418-resistant cell clones (800 µg mL–1) were screened by PCR with hA20-specific primers for hA20 integration. Eighty clones were A20-positive in PCR screening from 4 rounds of transfection. One cell clone was verified by DNA sequencing and subsequently used as donor cells in somatic cell nuclear transfer. One hundred sixty-nine embryos were transferred to 2 synchronized peripuberal German Landrace gilts, respectively. Ultrasound examination of recipient sows on Day 22 after embryo transfer confirmed established pregnancies in both recipients. One pregnancy was allowed to go to term and 7 healthy piglets were born, whereas the second pregnancy was terminated on Day 70 of pregnancy for detailed expression analysis of the 8 isolated fetuses. Results showed that the A20 vector can be integrated in PFF, and A20-transgenic PFF can be successfully used in somatic cell nuclear transfer to establish pregnancies. Further analysis will focus on the expression levels and patterns in A20-positive cell clones and the biological function in transgenic piglets. Functional assays will be conducted in vitro and in vivo. We thank Prof. Beyaert of Ghent University, Belgium for providing us with the expression vector pCAGGSEhA20.

309 PRODUCTION OF PIGS TRANSGENIC FOR HUMAN HEMEOXYGENASE-I BY SOMATIC NUCLEAR TRANSFER

The hyperacute rejection after porcine-to-human xenotransplantation can now be reliably overcome either by transgenic expression of complement regulating factors or by knocking out the gene for α1,3-galactosyltransferase in pigs. The next immunological hurdle is the acute vascular rejection (AVR) primarily caused by endothelial cell activation. Human hemeoxygenase-I (hHO-I) is known to have anti-apoptotic and cell-protective properties. Thus, the expression of hHO-I on porcine endothelial cells could have beneficial effects in a xenotransplantation setting to prevent the formation of AVR. Here we describe the first transgenic pigs with functional expression of hHO-I. Fibroblasts were obtained by an ear punch from a decay accelerating factor (DAF)-transgenic female pig and were cultured in vitro (Kues WA et al. 2005 Biol. Reprod. 72, 1020–1028). Cells reaching confluency of 70 to 80% were detached with EDTA/trypsin and subsequently transfected by electroporation at 450V/350 µF with a vector coding for hHO-I driven by the SV40 promoter. Transfected cells were selected for resistance against G418 (800 µg mL–1) for 14 days. Resistant cell clones were screened for integration of the vector by PCR. One positive cell clone that showed strong expression of the transgene, as determined by immunostaining, was selected for somatic nuclear transfer (Hoelker M et al. 2005 Cloning Stem Cells 7, 35–44). In total, 205 reconstructed embryos were transferred to 2 synchronized peripuberal German Landrace gilts, which gave birth to 9 live piglets, all with normal birth weights. PCR and Southern blot analyses revealed that all of the offspring had integrated the vector into their genome. Two transgenic animals were sacrificed for further characterization and ex vivo perfusion experiments. In these animals, Northern blotting showed weak transcription of the transgene in all xenorelevant organs such as heart, kidney, and liver. Immunostaining of the kidneys revealed that expression of the transgene was confined to the endothelial cell layer. These hHO-I-transgenic porcine kidneys were subjected to an ex vivo perfusion assay and survived ex vivo perfusion for 240 min with AB-pooled human blood, whereas perfusion of 2 non-transgenic controls had to be terminated after 60 min due to problems attributed to immunological rejection. Histology revealed that perfused hHO-I-transgenic kidneys exhibited no indication for xenogenic activation of the human coagulation system. These preliminary results show that functional hHO-I can be expressed in transgenic pigs and that transgenic expression of hHO-I might improve long-term survival of porcine xenografts. These results are encouraging and warrant further studies on endothelial cell activation and the biological function of hemeoxygenase-I in the context of xenotransplantation. This study was funded by the Deutsche Forschungsgemeinschaft Ni 256/22-1, -2, -3.

Ibuprofen sodium dihydrate, an ibuprofen formulation with improved absorption characteristics, provides faster and greater pain relief than ibuprofen acid

OBJECTIVE

The objective of this 6-hour study was to compare rate of pain relief, analgesic efficacy and tolerability of a novel ibuprofen formulation, ibuprofen sodium dihydrate, with that of ibuprofen acid in subjects with postoperative dental pain.

MATERIAL AND METHODS

The test formulation of ibuprofen sodium dihydrate (256 mg sodium salt) and the reference product both contain 200 mg ibuprofen. Subjects with moderate-to-severe pain after extraction of third molars were randomized to receive two tablets of either ibuprofen sodium dihydrate (198 subjects) or ibuprofen (198 subjects) in this double-blind, multicenter trial. Pain was measured using traditional descriptor scales and onset of analgesia assessed using the stop-watch method.

RESULTS

Median time to substantial pain relief occurred 14 minutes earlier in the ibuprofen sodium dihydrate group (p < 0.001). The first sign of pain relief, an increase in relief and time until the pain was half gone occurred significantly earlier and faster in the ibuprofen sodium dihydrate-treated patients (p < 0.02-0.00003). Corresponding numbers needed to treat were in the range 11. Reduction in pain intensity was evident within 5 minutes (p < 0.01) in the ibuprofen sodium dihydrate group compared to 15 minutes in the ibuprofen group. Pain intensity was reduced to half after 30 and 57 minutes in the ibuprofen sodium dihydrate and ibuprofen groups, respectively (p < 0.025). The overall analgesic efficacy in terms of summed pain intensity differences (SPID), total pain relief (TOTPAR) and remedication times in the two groups were similar. Both treatments were well tolerated and no serious events occurred.

CONCLUSION

Ibuprofen sodium dihydrate provides faster and more efficacious pain relief during the first hour after intake when compared to a conventional ibuprofen acid formulation. The tolerability profiles are similar.

76 PREOVULATORY EMBRYO TRANSFER INCREASES SUCCESS OF PORCINE SOMATIC CLONING

Somatic cloning has emerged as a valuable tool for the production of transgenic animals. However, the technology still suffers from low efficiencies (&lt;1%). In the present study, we used 2 different recipient synchronization protocols and assessed the effects on the cloning efficiency in pigs using triple transgenic donor cells within a bigger study on xenotransplantation. Double transgenic adult fibroblasts (hCD59/DAF) were transfected with a construct coding for human thrombomodulin (hTM). After selection with 800 µg mL−1 G418 for 14 days, cells were analyzed for integration of the construct by PCR and visually selected for expression of the hTM-GFP fusion protein. One positive cell clone was used for all nuclear transfers. Nuclear transfer (NT) was performed using in vitro-matured oocytes, as previously described (Hoelker et al. 2005 Cloning Stem Cells 7, 35–44). Peri-puberal German Landrace gilts were used as recipients in 2 different synchronization protocols. Group 1 received 1200 IU pregnant mare serum gonadotropin (PMSG) IM 117 h prior to embryo transfer, followed by 500 IU human chorionic gonadotropin (hCG) 72 h later. Nuclear transfer complexes were transferred surgically 46 h later, approximately 6 h post-ovulation. Group 2 was synchronized by administration of 5 mL Altrenogest for 12 days (20 mg gilt/day). At the end of treatment, the animals received 1000 IU PMSG IM, followed by an injection of 500 IU hCG 80 h later. Cloned embryos were transferred surgically approximately 20 h prior to ovulation. Maintenance of pregnancy was supported by injections of 1000 IU PMSG on Day 11 and 500 IU hCG on Day 14 of gestation. Animals were checked for pregnancy by ultrasound 25 days after transfer (Table 1). In group 1, only one pregnancy could be maintained, leading to the birth of one piglet after caesarean section. In contrast, 12 pre-ovulatory transfers resulted in 9 pregnancies with a total of 47 cloned piglets born. All offspring had normal birth weights (1.0–1.5 kg) and showed no malformations. Average litter size in group 2 was 5.2, and the overall efficiency was 3.1% and 4.4% when related to pregnant recipients. The results show that the transfer of NT-complexes into oviducts of pre-ovulatory recipients significantly improved the success rates of porcine cloning. This is an important feature for the production of transgenic pigs for biomedical and agricultural application. Table 1. Results of porcine nuclear transfer This project is funded by the Deutsche Forschungsgemeinschaft (FOR 535).

Lund Stroke Register: hospitalization pattern and yield of different screening methods for first-ever stroke

OBJECTIVES

To explore case ascertainment, hospitalization, characteristics of both hospitalized and non-hospitalized patients in a population-based group of stroke patients.

MATERIALS AND METHODS

One-year screening in Lund-Orup district for first-ever strokes using multiple prospective and retrospective methods.

RESULTS

A total of 456 patients with first-ever stroke (n = 412 prospective screening methods, n = 17 primary care, n = 12 hospital registers, n = 10 death register, n = 2 autopsy registers, n = 3 other). Hospitalization proportion within 14 days was 84%. Patients sent home from emergency unit (n = 36) were often males (75%), had low 28-day case-fatality (0%), and less severe strokes (median National Institute of Health Stroke Scale score 2 vs 4 for all). Patients managed solely within primary care (n = 18) were elderly (median age 89 vs 77 years for all), resided in nursing homes (86% vs 8% for all) and had high 28-day-case-fatality (61%).

CONCLUSIONS

Hospitalization was lower than expected. Two main categories of patients were not hospitalized: elderly patients at nursing homes with high case-fatality and patients with mild stroke.

43 INFLUENCE OF DONOR CELL DIFFERENTIATION ON CLONING EFFICIENCY IN PIGS

We recently reported the discovery of a novel type of stem cells which could be derived from primary cultures of fibroblasts by high density culture (Kues et al. 2005 Biol. Reprod. 72, 1020–1028). The goal of the present study was to analyze the suitability of this specific stem cell population (fetal somatic stem cells, FSSCs) in NT and to test their ability to produce normal offspring upon transfer of cloned embryos. In the first of 4 experiments, FSSCs from isolated attached colonies were compared with fetal fibroblasts in their ability to form blastocysts upon use in NT. Fusion and cleavage rates were similar between the two groups [FSSCs: 75.3 � 10.5% (mean � SD) vs. 83.7 � 9.2%; fetal fibroblasts: 64.8 � 17.3% vs. 82.5 � 5.6%, respectively]. Blastocyst rate differed significantly between the two groups (6.4 � 3.5% vs. 24.9 � 8.6%). In the second experiment, FSSCs of 3 different sizes (&lt;14 �m, 15–20 �m, &gt;21 �m), obtained from dissociation of spheroids, were compared in their ability to form blastocysts upon use in NT. No differences were found among the 3 groups (fusion rates: 93.0 � 3.1 vs. 91.3 � 10.1 vs. 92.3 � 5.1; cleavage rates: 83.5 � 7.9 vs. 83.1 � 1.6 vs. 83.2 � 5.8; blastocyst rates: 15.3 � 7.9 vs. 17.6 � 6.8 vs. 10.4 � 2.7, respectively). In the third experiment, FSSCs 15–20 �m in size, derived from spheroids, were compared with fetal fibroblasts. No differences were detected between groups (fusion rates: 83.3� 7.3% vs. 86.8 � 5.3%; cleavage rates: 86.1 � 6.7% vs. 80.7 � 5.9%; blastocyst rates: 21.4 � 5.6% vs. 18.4 � 5.6%, respectively). In the final experiment, 70–100 nuclear transfer complexes cloned from FSSCs were transferred immediately after activation to prepubertal gilts to evaluate their in vivo developmental potential. Pregnancies were established in 3 of 7 recipients, which delivered 7 piglets, of which 3 piglets were vital and showed normal development. Four piglets were lost due to dystocia. These results show that FSSCs are able to generate cloned embryos, and pregnancies can be established and vital piglets can be produced.

Inhibition of porcine endogenous retroviruses (PERVs) in primary porcine cells by RNA interference using lentiviral vectors

A potential risk in pig-to-human xenotransplantation is the transmission of PERVs to human recipients. Here we show for the first time the inhibition of PERV expression in primary porcine cells by RNA interference using lentiviral vectors. Cells were transduced with lentiviral vectors coding for short hairpin (sh) RNAs directed against PERV. In all primary porcine cells studied and in the porcine kidney cell line PK-15, expression of PERV-mRNA was significantly reduced as measured by real-time PCR. Most importantly, expression of PERV proteins was almost completely suppressed, as shown by Western blot analysis. Thus, lentiviral shRNA vectors could be used to knockdown PERV expression and create transgenic pigs with a reduced risk of PERV transmission during xenotransplantation.

How high should total pain-relief score be to obviate the need for analgesic remedication in acute pain? Estimation using signal detection theory and individual-patient meta-analysis

BACKGROUND

A pain relief score 50% of the maximum is often used as a clinically meaningful outcome in meta-analyses of analgesic trials. This arbitrary value requires validation.

OBJECTIVE

To determine the optimum pain relief score for predicting pain relief sufficient to obviate the need for analgesic remedication in acute post-surgical pain.

DESIGN

Individual-patient meta-analysis of randomized controlled trials and use of signal detection theory to identify the optimum cut-off point on the total pain relief score (TOTPAR). Analgesic remedication was used as the clinical outcome.

DATA SOURCES

Seven parallel-group, active and placebo-controlled trials of minor analgesics.

RESULTS

The predictive value of the TOTPAR score [expressed as a percentage of the maximum score (%maxTOTPAR)] for remedication was excellent for all the trials. The pooled estimate of the area under the receiver operating curve, an index of discriminative power, was outstanding 0.96 (95% CI 0.95-0.97). The pooled estimate of the optimal %maxTOTPAR for predictive purposes was 44.11 (95% CI 44.00-44.23).

CONCLUSION

The analysis suggests that the arbitrary 50% cut-off point TOTPAR score often used in meta-analyses of analgesic trials in dental pain is reasonably acceptable. This is different to the 33% cut-off point reported for analgesic trials of acute breakthrough cancer pain and some chronic pain states such as diabetic neuropathy and postherpetic neuralgia. These differences deserve careful consideration when reading reports of analgesic trials and meta-analyses. Remedication itself should be considered as the preferred outcome measure for analgesic trials.

67 GENERATION OF PIGS TRANSGENIC FOR hCD59/DAF AND HUMAN THROMBOMODULIN BY SOMATIC NUCLEAR TRANSFER

After a porcine–to–primate xenotransplantation, hyperacute rejection (HAR) destroys the transplanted organ within minutes. The HAR can be overcome either by a knockout of the gene for α–1,3–galactosyltransferase or by overexpression of human complement regulatory proteins such as hCD59 and DAF. When HAR can be controlled, the next hurdle is acute vascular rejection (AVR) which is primarily due to an incompatibility of human protein C and porcine thrombomodulin, both of which are important factors in the coagulation cascade. This incompatibility leads to thrombosis and finally to a disseminated intravascular coagulation (DIC), causing rejection of the xenotransplant. Human thrombomodulin is a good candidate gene for improving survival time of porcine organs after xenotransplantation and for overcoming AVR. Here, we transfected adult fibroblasts obtained from a double transgenic boar (hCD59/DAF) with a construct for human thrombomodulin (hTM). After selection with 800 μg/mL G418 for 14 days, cells were analyzed for integration of the construct by PCR and were visually selected for expression of the hTM–GFP fusion protein under ultraviolet light with a fluorescein isothiocyanate (FITC) filterset. A total of 39 positve clones were obtained, of which two were used in somatic nuclear transfer. Ovaries were collected from a local slaughterhouse, and follicles of 2–5 mm in diameter were aspirated. After 38–42 h of in vitro maturation oocytes were denuded and enucleated. For cell cycle synchronization, the donor cells were serum–starved for 48 h, subsequently trypsinized and placed into the perivitelline space of the enucleated oocytes. The complexes were fused and activated electrically followed by an incubation in DMAP for 3 h. Puberal gilts were synchronized by treatment with 5 mL Regumate® (Intervet UK, Ltd., Milton Keynes, Buckinghamshire, UK) for 13 days. At the end of treatment, the animals received 1000 IU pregnant mare serum gonadotropin (PMSG) intramuscularly followed by an injection of 500 IU hCG 72 h later. Cloned embryos were transferred surgically 20 h after hCG injection. Maintenance of pregnancy was supported by injections of 1000 IU PMSG on Day 11 and 500 IU hCG on Day 14 of the pregnancy. Out of 1409 reconstructed complexes, 1161 were fused (82.4%) successfully. In total, 1040 embryos were transferred to 8 recipients (∼130 embryos/gilt, range 70–162). Five of the eight recipients (62.5%) became pregnant as determined by ultrasound on Days 25, 36, and 51 and will farrow within the next weeks. These results show that cloning with triple transgenic adult donor cells is compatible with high pregnancy rates. Porcine multitransgenic organs will be used in perfusion experiments to test the effectiveness of this novel approach to overcoming the incompatibilities between the porcine and the human coagulation systems. This project is funded by the Deutsche Forschungsgemeinschaft (FOR 535). The hTM–construct was a gift of Dr. Wu which is gratefully acknowledged.

63 IMPROVED IN VITRO DEVELOPMENT OF PORCINE EMBRYOS PRODUCED BY NUCLEAR TRANSFER, IVF AND PARTHENOGENESIS

Porcine nuclear transfer (NT) is an inefficient process and it is necessary to use as many as 120 NT embryos for each foster mother to obtain small litters of live piglets. In these experiments, we evaluated the effects of culture atmosphere and medium on the development of NT embryos by monitoring blastocyst rate and cell number of Day 6 blastocysts. Age matched IVF and parthenogenetic embryos were also evaluated for comparison. For all experiments a pool of oocytes was aspirated from ovaries collected in a local abattoir. Following aspiration, oocytes were allowed to mature for 40 h in North Carolina State University (NCSU)-37 medium (supplemented with cAMP and hCG/eCG for the first 22 h). After removal of the cumulus cells, denuded oocytes with polar bodies were selected for NT, enucleated, fused with fetal fibroblasts, and sequentially activated electrically and chemically by 3 h of treatment with 6-dimethylaminopurine (6-DMAP). A second group of oocytes from the same denuded pool were maintained in TL-HEPES medium and activated in parallel with the NT group to produce parthenogenetic embryos. A third group was fertilized with frozen-thawed epididymal semen and co-cultured for ∼12 h to give IVF embryos. All three treatment groups were subdivided into a control subgroup and an experimental subgroup. In the first experiment, we compared the effects of atmosphere (20% vs. 5% oxygen) on in vitro embryonic development in NCSU-23 medium. In the second experiment, we used only the 5% oxygen concentration and compared different culture media. One subgroup was maintained in standard NCSU-23 medium and the second subgroup was cultured in a two-step system for the first 58 h in modified NCSU-23 (without glucose but supplemented with 2.0 mM lactate and 0.2 mM pyruvate), followed by addition of glucose to give a final concentration of 5.55 mM. Data were statistically analyzed by analysis of variance and chi square test. Blastocyst rate and mean cell number in all three embryo groups were improved under 5% oxygen. The most dramatic effect was observed in the NT group, in which the blastocyst rate increased significantly (P < 0.001) from 6.7% ± 5.9 (n = 279) to 19.6% ± 8.9 (n = 250) and mean cell number increased from 17.7 ± 12.1 to 25.8 ± 10.3 cells per blastocyst. With 5% oxygen there was also an increase of blastocyst rates and mean cell numbers in both IVF and parthenogenetic groups. In the second experiment, blastocyst rate for NT embryos increased significantly (P < 0.05) from 21.8% ± 7.6 (n = 242) in conventional NCSU-23 to 31.5% ± 11.0 (n = 271) in the modified system whereas there was almost no difference in the mean cell number of both groups (29.2 ± 4.3 vs. 31.5 ± 5.3). In the groups of IVF and parthenogenetic embryos no difference was found. These results indicate that both the reduced oxygen and the modified culture medium are important for pre-implantation development of porcine nuclear transfer embryos.

Primary Stenting of Subclavian and Innominate Artery Occlusive Disease: A Single Center?s Experience

PURPOSE

To review immediate and midterm results of primary stenting for innominate and subclavian artery occlusive lesions.

METHODS

Retrospective data were collected from 48 consecutive symptomatic patients (27 men and 21 women, median age 64 years) having 49 subclavian and innominate artery lesions treated with stenting. Of the patients 52% had concomitant ischemic heart disease, and 30% had carotid and/or vertebral artery disease. Indication for treatment was vertebrobasilar insufficiency (VBI) in 16.6% of the patients; upper limb ischemia (ULI) in 31.3%; VBI and ULI in 12.5%; transient ischemic attack in 16.7%; angina in 12.5% before or after left internal mammary artery-to-coronary artery bypass grafting; and leg claudication in 10.4% before or after axillofemoral bypass grafting. Balloon-expandable stents were used in 44 lesions and self-expandable stents in 5 lesions. In total, 53 stents were placed in 48 patients.

RESULTS

Technical success was 96%, and clinical success 94%. We encountered four complications (two puncture site hematomas, one distal hand embolization and one transient cerebral ischemia). Two patients died within 30 days from other causes, and seven patients were lost to follow-up. Mean follow-up time was 16.7 months (range 0.3 to 68.2). Five patients had recurrent lesions treated by surgical (n = 2) or endovascular (n = 3) means. Cumulative primary patency rate was 91.7% and 77% at 12 and 24 months, respectively. Cumulative secondary patency rate was 96.5% and 91.7% at 12 and 24 months, respectively.

CONCLUSION

Stenting of subclavian and innominate artery lesions resulted in immediate resolution of patients' symptoms with durable midterm effect and few complications in a larger patient group with serious comorbid conditions.

66EFFECTS OF CONTACT INHIBITION INTERVALS V. SERUM DEPRIVATION ON DEVELOPMENT OF PORCINE NUCLEAR TRANSFER DERIVED EMBRYOS

Contact inhibition and serum deprivation are commonly used to synchronize donor cells at the G0/G1 state of the cell cycle prior to use in nuclear transfer. Here we compared the effects of serum deprivation (SD) and different intervals of contact inhibition (CI) of the donor cells on the blastocyst rate. One batch from pooled porcine fetal fibroblasts (passage 3) was used in this study. The cells were thawed, seeded to a six-well plate and cultured in Dulbecco‘s Modified Eagles Medium (DMEM) supplemented with 2mM glutamine, 1% non-essential amino acids, 0.1mM mercaptoethanol, 100UmL−1 penicillin, 100mgmL−1 streptomycin containing 10% fetal calf serum (FCS). Serum deprivation was achieved by culturing cells in DMEM containing 0.5% FCS for 48h. Cells of the CI groups were grown to 100% confluency and kept in that state for 24h, 48h and 72h. Immediately after cell cycle synchronization, cells were used in nuclear transfer. Cell cycle state of the cells was evaluated by FACS analysis at 24h after beginning of CI and prior to nuclear transfer. Blastocyst rate was determined 7 days after nuclear transfer. An average of 38-42h in vitro matured oocytes were used in nuclear transfer (NT). NT was performed as described previously (Betthauser J et al., 2000 Nat. Biotechnol. 17, 456–461). There were no differences in the proportion of cells in G0/G1 of the cell cycle in any of the treatment groups (85.0%, 85.8%, 85.5% and 86.3% for SD and CI at either 24h, 48h and 72h, respectively). After nuclear transfer (for each CI group n=336–384 reconstr. embryos; SD n=215) there was a statistically significant difference in the fusion rate between 48h CI and SD cells (74.8% v. 87.5%, t-test P&lt;0.050). Blastocyst rate (blastocysts/fused) differed significantly between SD, 24h CI and 48h CI (17.4%; 9.1%, 9.6%, t-test P&lt;0.050), there was no difference between SD and 72h CI and within the CI groups (72h CI 10.6%). Four transfers of reconstructed embryos (72h CI, n=138–163 embryos/gilt, 1-cell embryos) to prepuberal Landrace gilts led to 2 initial pregnancies determined at Day 25 by ultrasound. One pregnancy was lost at Day 35; the other recipient remained pregnant and farrowed 4 piglets. One piglet was stillborn and one died 7h after birth; the remaining two piglets are healthy and now 4 months old. Four transfers of embryos (n=96–110) reconstructed with SD cells revealed two initial pregnancies determined on Day 25 by ultrasound. Again, one was lost on Day 35, and the other one is now at Day 100. Our results show that, despite similar proportions of cells being in G0/G1 of the cell cycle, cells either contact-inhibited for 72h or serum-deprived both show higher rates of blastocyst development compared to cells contact-inhibited for shorter time periods. Both donor cell preparations can lead to full term development of nuclear transfer-derived embryos. This work was funded by the Deutsche Forschungsgemeinschaft (DFG, SFB 265).

Rapsyn N88K is a frequent cause of congenital myasthenic syndromes in European patients

BACKGROUND

Mutations in various genes of the neuromuscular junction may cause congenital myasthenic syndromes (CMS). Most mutations identified to date affect the epsilon-subunit gene of the acetylcholine receptor (AChR), leading to end-plate AChR deficiency. Recently, three different mutations in the RAPSN gene have been identified in four CMS patients with AChR deficiency.

OBJECTIVE

To perform mutation analysis of the RAPSN gene in patients with sporadic or autosomal recessive CMS.

METHODS

One hundred twenty CMS patients from 110 unrelated families were analyzed for the RAPSN mutation N88K by restriction fragment length polymorphism and sequence analysis.

RESULTS

In 12 CMS patients from 10 independent families, RAPSN N88K was identified either homozygous or heteroallelic to another missense mutation. Symptoms usually started perinatally or in the first years of life. However, one patient did not show any myasthenic symptoms before the third decade. Clinical symptoms typically included bilateral ptosis, weakness of facial, bulbar, and limb muscles, and a favorable response to anticholinesterase treatment. Crisis-like exacerbations with respiratory insufficiency provoked by stress, fever, or infections in early childhood were frequent. All RAPSN N88K families originate from Central or Western European countries. Genotype analysis indicated that they derive from a common ancestor (founder).

CONCLUSIONS

The RAPSN mutation N88K is a frequent cause of rapsyn-related CMS in European patients. In general, patients (RAPSN N88K) were characterized by mild to moderate myasthenic symptoms with favorable response to anticholinesterase treatment. However, severity and onset of symptoms may vary to a great extent.