PURPOSE: Blind individuals who have photoreceptor loss are known to perceive phosphenes with electrical stimulation of their remaining retinal ganglion cells. We proposed that implantable lateral geniculate body (LGB) stimulus electrode arrays could be used to generate phosphene vision. We attempted to refine the basic reference of the electrical evoked potentials (EEPs) elicited by microelectrical stimulations of the optic nerve, optic tract and LGB of a domestic pig, and then compared it to visual evoked potentials (VEPs) elicited by short-flash stimuli. METHODS: For visual function measurement, VEPs in response to short-flash stimuli on the left eye of the domestic pig were assessed over the visual cortex at position Oz with the reference electrode at Fz. After anesthesia, linearly configured platinum wire electrodes were inserted into the optic nerve, optic track and LGB. To determine the optimal stimulus current, EEPs were recorded repeatedly with controlling the pulse and power. The threshold of current and charge density to elicit EEPs at 0.3 ms pulse duration was about ±10 microA. RESULTS: Our experimental results showed that visual cortex activity can be effectively evoked by stimulation of the optic nerve, optic tract and LGB using penetrating electrodes. The latency of P1 was more shortened as the electrical stimulation was closer to LGB. The EEPs of two-channel in the visual cortex demonstrated a similar pattern with stimulation of different spots of the stimulating electrodes. We found that the LGB-stimulated EEP pattern was very similar to the simultaneously generated VEP on the control side, although implicit time deferred. CONCLUSIONS: EEPs and VEPs derived from visual-system stimulation were compared. The LGB-stimulated EEP wave demonstrated a similar pattern to the VEP waveform except implicit time, indicating prosthetic-based electrical stimulation of the LGB could be utilized for the blind to perceive vision of phosphenes.
Animals ; Electric Stimulation ; Electrodes, Implanted ; Evoked Potentials, Visual/*physiology ; Geniculate Bodies/*physiology ; Male ; Optic Nerve/physiology ; Optic Tract/physiology ; Photic Stimulation ; Sus scrofa ; Visual Cortex/*physiology

The level of P4 at the time of embryo transfer (ET) is important. P4 concentrations and numbers of corpora lutea for 126 recipients were evaluated. Nuclear transfer embryos were transferred into 126 surrogates. 11 maintained their pregnancy until full-term delivery, 17 miscarried, and implantation failed in 98 animals. P4 levels in the full-term group were significantly different from those of the pigs that aborted or in which implantation failed (p < 0.05). However, the numbers of corpora lutea were not significantly different. These findings indicate that the concentration of progesterone can be an important factor for successful ET in pigs.
Animals ; Corpus Luteum/*physiology ; Embryo Transfer/*veterinary ; Embryo, Mammalian/*physiology ; Female ; Nuclear Transfer Techniques ; Pregnancy ; *Pregnancy Rate ; Progesterone/*blood ; Retrospective Studies ; Sus scrofa/*physiology

Pigs are the most likely source animals for cardiac xenotransplantation. However, an appropriate method for estimating the cardiac function of micropigs had not been established. Computed tomography (CT) analysis aimed at estimating cardiac function and assessing the coronary arteries has not been carried out in micropigs. This study determined the feasibility of evaluating cardiac function in a micropig model using multidetector row computed tomography (MDCT) and compared the cardiac function values with those of conventional pigs. The mean age of the conventional pigs and micropigs was approximately 80 days and approximately 360 days, respectively. The mean body weight in the conventional pigs and micropigs was 29.70 +/- 0.73 and 34.10 +/- 0.98 kg, respectively. Cardiac MDCT detected ejection fractions of 52.93 +/- 3.10% and 59.00 +/- 5.56% and cardiac outputs of 1.46 +/- 0.64 l/min and 1.21 +/- 0.24 l/min in conventional pigs and micropigs, respectively. There were no significant differences in cardiac function between conventional pigs and micropigs in the reconstructed CT images. There were also no differences in the coronary angiographic images obtained by MDCT. It is expected that the results of this study will help improve understanding of cardiac function in micropigs. The data presented in this study suggest that MDCT is a feasible method for evaluating cardiac function in micropigs.
Animals ; Coronary Angiography/*methods ; Heart/*physiology/radiography ; *Models, Animal ; Sus scrofa/*physiology ; Swine ; Swine, Miniature/*physiology ; Tomography, X-Ray Computed/*methods

OBJECTIVETo detect the stromal cell derived factor 1 (SDF-1) expression during the survival process of the narrow pedicle flap with hypoxia and ischemia and to investigate the role of SDF-1/ CXCR4 axis in flap neovascularization.

METHODSThe narrow pedicle flaps were formed on the bilateral back of 5 pigs. The pedicle ratio of length to width was 4:2. The flap size was 2 cm x 2 cm (group A), 3 cm x 3 cm (group B), 4 cm x 4 cm (group C), 5 cm x 5 cm(group D), 6 cm x6 cm (group E). The flaps survival rate was observed and HE staining was performed. The SDF-1 expression at the distal end of flaps was detected by ELISA during the operation and 3, 5, 7, 14 days after operation.

RESULTS(1) SDF-1 expression at the same group increased after operation until it reached the peak value at 5 days after operation; then it decreased to basic value. (2) SDF-1 expression in different groups was higher in bigger flaps until the flaps size reached 5 cm x 5 cm. Then partial necrosis happened at the distal end of flaps.

CONCLUSIONSThe SDF-1 expression may be related to the blood supply during the survival process of the narrow pedicle flap with hypoxia and ischemia.

Animals ; Cell Hypoxia ; physiology ; Chemokine CXCL12 ; metabolism ; Graft Survival ; physiology ; Ischemia ; physiopathology ; Male ; Signal Transduction ; Surgical Flaps ; blood supply ; physiology ; Sus scrofa ; Swine

This study examined effects on the developmental competence of pig oocytes after somatic cell nuclear transfer (SCNT) or parthenogenetic activation (PA) of : 1) co-culturing of oocytes with follicular shell pieces (FSP) during in vitro maturation (IVM); 2) different durations of maturation; and 3) defined maturation medium supplemented with polyvinyl alcohol (PVA; control), pig follicular fluid (pFF), cysteamine (CYS), or beta-mercaptoethanol (beta-ME). The proportion of metaphase II oocytes was increased (p < 0.05) by co-culturing with FSP compared to control oocytes (98% vs. 94%). However, blastocyst formation after SCNT was not improved by FSP coculture (9% vs. 12%). Nuclear maturation of oocytes matured for 39 or 42 h was higher (p < 0.05) than that of oocytes matured for 36 h (95-96% vs. 79%). Cleavage (83%) and blastocyst formation (26%) were significantly higher (p < 0.05) in oocytes matured for 42 h than in other groups. Supplementation of a defined maturation medium with 100 micrometer CYS or 100 micrometer beta-ME showed no stimulatory effect on oocyte maturation, embryo cleavage, or blastocyst formation after PA. beta-ME treatment during IVM decreased embryo cleavage after SCNT compared to pFF or PVA treatments, but no significant difference was found in blastocyst formation (7-16%) among the four treatment groups. The results indicated that maturation of oocytes for 42 h was beneficial for the development of SCNT embryos. Furthermore, the defined maturation system used in this study could support in vitro development of PA or SCNT embryos.
Animals ; Cysteamine ; Embryo Culture Techniques/*veterinary ; Embryo, Mammalian/*physiology ; Female ; Follicular Fluid ; Mercaptoethanol ; Nuclear Transfer Techniques/*veterinary ; Oocytes/*growth & development ; Sus scrofa/*physiology ; Time Factors

This study was conducted to establish an in vitro maturation (IVM) system by selection of efficient porcine serum during porcine in vitro production. To investigate the efficient porcine serum (PS), different types of PS [newborn pig serum, prepubertal gilt serum (PGS), estrus sow serum, and pregnancy sow serum] were used to supplement IVM media with or without gonadotrophin (GTH) and development rates of parthenogenetic activation (PA) and in vitro fertilization (IVF) embryos were then compared. The maturation rates of the PGS group was significantly higher when GTH was not added. Additionally, during development of PA embryos without GTH, the PGS group showed significantly higher cleavage and blastocyst formation rates. Moreover, the cleavage rates of IVF embryos were significantly higher in the PGS group, with no significant differences in the blastocyst formation. However, when GTH was supplemented into the IVM media, there were no significant differences among the four groups in the cleavage rates, development rates of the blastocyst, and cell number of the blastocyst after PA and IVF. In conclusion, PGS is an efficient macromolecule in porcine IVM, and GTH supplementation of the IVM media is beneficial when PS is used as macromolecule, regardless of its origin.
Animals ; Blastocyst/*drug effects ; Embryo, Mammalian/drug effects/*embryology/physiology/ultrastructure ; Fertilization in Vitro/veterinary ; Gonadotropins/administration & dosage/*metabolism ; In Vitro Oocyte Maturation Techniques/*methods/veterinary ; Parthenogenesis/*drug effects ; Sus scrofa/*embryology

Classical swine fever (CSF) is a contagious swine disease charactered by hemorrhagic fever and leukopenia,usually leading to substantial economic losses. To obtain a insight of leucopenia caused by CSFV infection, DNA microarray analyses of peripheral blood leucocytes (PBL) of the infected pigs was performed. Three health pigs were inoculated with a lethal dose of CSFV Shimen strain and their PBLs were isolated when the onset of typical clinical signs and then subjected to total RNA extraction followed by microarray analysis with Affymetrix Porcine Genome Array GeneChips. The results showed that the significant differences were observed in cellular apoptotic genes expression at 7 days post-infection (p. i.). The changes of the genes expression were confirmed by real time RT-PCR of some selected apoptosis-related genes. This study provided a valuable information for further investigating the molecular mechanism of apoptosis caused by CSFV infection.
Animals ; Apoptosis ; Cells, Cultured ; Classical Swine Fever ; genetics ; immunology ; virology ; Classical swine fever virus ; immunology ; physiology ; Gene Expression Profiling ; Leukocytes, Mononuclear ; cytology ; immunology ; virology ; Molecular Sequence Data ; Oligonucleotide Array Sequence Analysis ; Sus scrofa