Identification and characterization of an oocyte factor required for development of porcine nuclear transfer embryos

Nuclear reprogramming of differentiated cells can be induced by oocyte factors. Despite numerous attempts, these factors and mechanisms responsible for successful reprogramming remain elusive. Here, we identify one such factor, necessary for the development of nuclear transfer embryos, using porcine oocyte extracts in which some reprogramming events are recapitulated. After incubating somatic nuclei in oocyte extracts from the metaphase II stage, the oocyte proteins that were specifically and abundantly incorporated into the nuclei were identified by mass spectrometry. Among 25 identified proteins, we especially focused on a multifunctional protein, DJ-1. DJ-1 is present at a high concentration in oocytes from the germinal vesicle stage until embryos at the four-cell stage. Inhibition of DJ-1 function compromises the development of nuclear transfer embryos but not that of fertilized embryos. Microarray analysis of nuclear transfer embryos in which DJ-1 function is inhibited shows perturbed expression of P53 pathway components. In addition, embryonic arrest of nuclear transfer embryos injected with anti-DJ-1 antibody is rescued by P53 inhibition. We conclude that DJ-1 is an oocyte factor that is required for development of nuclear transfer embryos. This study presents a means for identifying natural reprogramming factors in mammalian oocytes and a unique insight into the mechanisms underlying reprogramming by nuclear transfer.     

Technical dilemma in living-donor or split-liver transplant

In partial liver transplantation for adults criteria for the extent of reconstruction of middle hepatic vein tributaries have not been clarified. After hepatic venous and portal anastomoses in living-donor liver transplantation using left liver graft without middle hepatic vein, color Doppler ultrasonography was applied to check venous and portal blood flow. Color Doppler ultrasonography demonstrated absent hepatic venous flow and reversed portal venous flow in the congested area of the left paramedian sector which had been drained by the divided branch of the middle hepatic vein. The area was darkly discolored before arterial reperfusion and under clamping of the artery. Reconstruction of the venous branch was added after arterial anastomosis. Color Doppler ultrasonography revealed restored normal venous outflow and portal inflow after venous reconstruction. Postoperative course of the recipient was uneventful with rapid recovery of liver function. We propose that middle hepatic vein tributaries should be reconstructed if color Doppler ultrasonography demonstrates absent venous flow and reversed portal flow, and if the liver volume excluding the discolored area under occlusion of the hepatic artery is estimated to be insufficient for postoperative metabolic demand.     

Sympathoexcitation by brain oxidative stress mediates arterial pressure elevation in salt-induced chronic kidney disease

Hypertension is very prevalent in chronic kidney disease and critical for its prognosis. Sympathoexcitation and oxidative stress have been demonstrated to be involved in chronic kidney disease. We have shown previously that sympathoexcitation by brain oxidative stress mediates arterial pressure elevation in the salt-sensitive hypertension model, Dahl salt-sensitive rats. Thus, we investigated whether sympathoexcitation by excessive brain oxidative stress could contribute to arterial pressure elevation in salt-induced chronic kidney disease model rats. Young (3-week-old) male Sprague-Dawley rats were randomly assigned to a uninephrectomy or sham operation and then subjected to either a normal salt (0.5%) or high-salt (8.0%) diet for 4 weeks. The young salt-loaded uninephrectomized rats exhibited sympathoexcitation, hypertension, and renal injury, proteinuria and global glomerulosclerosis together with tubulointerstitial damage. Under urethane anesthesia and artificial ventilation, renal sympathetic nerve activity, arterial pressure, and heart rate decreased to a greater degree in the salt-loaded uninephrectomized rats than in the nonsalt-loaded uninephrectomized rats and the salt-loaded or nonsalt-loaded sham-operated rats, when Tempol, a membrane-permeable superoxide dismutase mimetic, was infused acutely into the lateral cerebral ventricle. Oxidative stress in the hypothalamus, measured by lucigenin chemiluminescence, was also significantly greater. Furthermore, in the salt-loaded uninephrectomized rats, antioxidant treatment with chronic intracerebroventricular Tempol decreased sympathetic nerve activity and arterial pressure, which, in turn, led to a decrease in renal damage. Similar effects were elicited by treatment with oral moxonidine, the central sympatholytic agent. In conclusion, sympathoexcitation by brain oxidative stress may mediate arterial pressure elevation in salt-induced chronic kidney disease.     

Increase in natural killer cell activity following living-related liver transplantation

Abstract We monitored the serial changes of natural killer cell (NK) activity in eight recipients of living-related liver transplantation. The HLA types of all eight patients were haplotypically identical with those of their donors. Tacrolimus and methylprednisolone were used for immunosuppression. The NK activity before transplantation was 24.1 ± 20.2 % which is surprisingly low when compared with the value for normal individuals (67.7 ± 13.2%, P < 0.01) or a liver dysfunction group (49.4 ± 21.9%, P < 0.05). Serial changes in NK activity revealed a minimum of 6.1 ± 3.6% 1 week after transplantation, gradually increasing to 49.2 ± 12.5 % at 2 months after transplantation. These results suggest that the diseased liver might play an important role in the suppression of NK activity.     

Reduction of intestinal adhesions by postoperative peritoneal irrigation with dialysis solution

In a canine experimental model in which intestinal adhesions were created by exposing the intestine to talc powder and autologous blood, the incidence of adhesion formation and the severity of adhesions were reduced tenfold when the abdominal cavity was irrigated with peritoneal dialysis solution three times daily for 4 days postoperatively. The mechanism of peritoneal dialysis solution in reducing the severity of adhesion appears to be related to the mechanical factors of washing out debris from the abdominal cavity, although it may also have a fibrinolytic effect. Long-term use of peritoneal dialysis solution may alter systemic fluid and electrolyte imbalance. Placing a small peritoneal dialysis catheter in the abdominal cavity at the conclusion of major abdominal operations and subsequent daily irrigation with peritoneal dialysis solution may be a helpful adjunct in reducing the incidence of postoperative adhesions.     

Reduction of postinfusion venous endothelial injury with intralipid

Hypertonic dextrose solutions, an essential part of parenteral nutrition infusions, have a sclerogenic effect upon vascular endothelium and frequently cause phlebitis or thrombosis, or both. Buffering D10W and D20W infusions to a pH of 7.4 slightly reduces the severity of endothelial injury. Infusion of Intralipid into canine veins during a 24 hour period produces negligible evidence of endothelial injury. Infusing concentrated dextrose solutions simultaneously through the same vein with Intralipid appreciably minimizes endothelial injury; when combined with bicarbonate buffering, the beneficial reduction of endothelial damage is significant (p less than 0.001) as seen on SEM and LM. In our opinion, long term infusion of Intralipid simultaneously with hypertonic dextrose is preferable to the currently recommended technique of separate infusion.     

A neonatal case of thoracoabdominal duplication associated with right congenital diaphragmatic hernia, absent inferior vena cava, and congenital portoazygous shunt: etiopathogenesis and surgical management

We report on a neonatal case of thoracoabdominal duplication associated with a split notochord syndrome and multiple anomalies. A newborn girl had severe dyspnea and was transferred to our neonatal care unit. At laparotomy, the entire small bowel was herniated into the posterior mediastinum through a defect in the right hemidiaphragm. The small bowel mesentery was firmly fixed to the mediastinum such that a large part of the small bowel could not be repositioned into the abdominal cavity. Imaging studies revealed an absent inferior vena cava with an azygous continuation. The superior mesenteric vein joined the splenic vein to form a portoazygous shunt that ran caudally through the mediastinum and drained into the azygous vein. The patient's intrahepatic portal vein was completely absent. To the best of our knowledge, this is the first reported case of a thoracoabdominal duplication associated with a portoazygous shunt. The etiopathogenesis and surgical management of this complicated case are discussed.     

Impact of previous multiple portoenterostomies on living donor liver transplantation for biliary atresia

BACKGROUND/AIMS: The present study examined the impact of portoenterostomy on the morbidity and mortality of patients who later underwent living donor liver transplantation for biliary atresia. METHODOLOGY: Sixty-one consecutive patients from January 1996 to May 2001 were analyzed. They were divided into two groups according to the number of previous portoenterostomies: once (group A, n=26) and twice or more (group B, n=35). Preoperative status, mortality, morbidity, hospital duration and survival were examined and compared between the groups. RESULTS: Preoperative parameters regarding liver function and urgency status were comparable between the groups. The operation duration tended to be longer in group B than in group A (p=0.07). The blood loss and transfusion volumes in group B were greater than those in group A (p=0.03 for both comparisons). Vascular complications tended to be more frequent in group B patients. However, this difference was not significant (12% vs. 29%, p=0.06). The duration of hospitalization was longer in group B (p=0.04). Survival rates were comparable between the groups. CONCLUSIONS: Our surgical results suggest that multiple previous portoenterostomies might have negative short-term effects in patients who undergo living donor liver transplantation for biliary atresia.     

The association between orthostatic increase in pulse pressure and ischemic heart disease

The clinical meaning of changes in PP with posture remains unclear. We performed treadmill exercise testing on 144 subjects to diagnose ischemic heart disease, and measured the PPs in the supine and standing positions. The differences in the two PPs ranged between ?35 and 45?mmHg. Eleven subjects were diagnosed with significant coronary ischemia. The differences in the PPs were significantly increased, and PP in the standing position was significantly elevated in these subjects. A large difference in the PPs in the standing and supine positions was associated with significant coronary ischemia, independent of significant covariables.