Thermoreversible gelation polymer induces the emergence of hepatic stem cells in the partially injured rat liver.

Focal injury of the adult liver causes formation of granulomatous tissue and fibrosis. When thermoreversible gelation polymer (TGP) was applied to such defects of the rat liver, complete recovery of hepatic tissues was observed without granulation. We analyzed the mechanism of the regeneration. TGP is a chemically synthesized biocompatible polymer material whose sol-gel transition is reversible by changing the temperature. Cooled TGP was poured into a penetration lesion of the rat liver. Immunohistochemistry and polymerase chain reaction were carried out using tissues and cultured cells isolated from ductular structures. Immunocytochemical and ultrastructural analyses were also conducted. Seven days after TGP treatment, ductular reactions were observed around the wound and ductules elongated to the injured area. Cells in the structures were alpha-fetoprotein (AFP) positive, albumin+, CK19+, c-Kit+, and Thyl+. Hepatocyte-like cells possessing glycogen appeared around the tips of the ductules from day 9. The defect was completely replaced with hepatocytes by day 28. Cells isolated from the ductules expressed Musashi-1, c-Kit, Thyl, AFP, albumin, transferrin, connexin 43, and CK19. When the cultured cells were covered by TGP, they rapidly proliferated to form colonies, whereas without TGP cells gradually died. Morphologically and ultrastructurally the cells were similar to hepatocytes. They expressed not only albumin and transferrin but TAT, CYP2E1, and CCAAT/enhancer binding protein a. Some cells formed bile canaliculus-like structures. In conclusion, TGP may trigger the initiation of hepatic stem cells in biliary ductules, and stem cell activation may occur even in the regeneration of the normal liver.

Introduction of the MASH1 gene into mouse embryonic stem cells leads to differentiation of motoneuron precursors lacking Nogo receptor expression that can be applicable for transplantation to spinal cord injury.

ES cells transfected with the MASH1 gene yielded purified spinal motoneuron precursors expressing HB9 and Islet1. The cells lacked the expression of Nogo receptor that was of great advantage for axon growth after transplantation to an injured spinal cord. After transplantation, mice with the complete transection of spinal cord exhibited excellent improvement of the motor functions. Electrophysiological assessment confirmed the quantitative recovery of motor-evoked potential in the transplanted spinal cord. In the grafted spinal cord, gliosis was inhibited and Nogo receptor expression was scarcely detected. The transplanted cells labeled with GFP showed extensive outgrowth of axons positive for neurofilament middle chain, connected to each other and expressed Synaptophysin, Lim1/2 and Islet1. Thus, the in vivo differentiation into mature spinal motoneurons and the reconstitution of neuronal pathways were suggested. The grafted cell population was purified for neurons and was free from teratoma development. These therapeutic strategies may contribute to a potent treatment for spinal cord injury in future.

Evaluation of out-of-hospital cardiopulmonary resuscitation with resuscitative drugs: a prospective comparative study in Japan.

OBJECTIVE: This study aimed at evaluating two emergency medical service systems, one in which emergency life-saving technicians (ELSTs) are allowed to administer epinephrine (adrenaline) to patients with out-of-hospital cardiac arrest and one in which ELSTs are allowed to administer epinephrine, lidocaine, and atropine. METHODS: A modified, prospective community health trial was conducted from April 1 to October 31, 2003. Areas served by physician-manned ambulances, where out-of-hospital cardiopulmonary resuscitation (CPR) was performed with resuscitative drugs (experimental areas), were compared to areas served by ELST-manned ambulances, where resuscitative drugs were not administered outside the hospital (reference areas). The sequence of emergency procedures performed in the experimental areas was divided into three phases. Phase I included administration of epinephrine, which simulated administration of epinephrine by ELSTs. Phase II started with the use of lidocaine or atropine. Phases I and II simulated administration of epinephrine, lidocaine, and atropine by ELSTs. Phase III began with administration of another drug. Outcomes, resuscitation rates and 1-month survival rates were determined, and differences between the two types of areas were analyzed. RESULTS: For non-traumatic cardiac arrest, outcomes through phase II in the experimental areas were significantly better than those in the reference areas. Phase I-only outcomes in the experimental areas were better, but not significantly better, than those in the reference areas. CONCLUSION: Use of resuscitative drugs for non-traumatic prehospital CPR appears to be effective in terms of resuscitation rates and 1-month survival rates.

The role of HMGB-1 on the development of necrosis during hepatic ischemia and hepatic ischemia/reperfusion injury in mice.

BACKGROUND: High-mobility group 1 (HMGB-1) is a late mediator of endotoxin lethality in mice. The release of HMGB-1 is delayed compared to other proinflammatory cytokines that mediate shock and tissue injury. The purpose of this study was to investigate the role of HMGB-1 levels in response to hepatic ischemia, hepatic I/R injury, and the relationship between changes in HMGB-1 and other cytokines. MATERIALS AND METHODS: Three murine models were employed: our robust model of segmental hepatic warm ischemia (SHWI), a model of partial hepatic ischemia/reperfusion injury (PHIRI), and a model of total hepatic ischemia/reperfusion injury (THIRI). Over a 48-h period following ischemic insult and reperfusion using these models, serum HMGB-1 concentrations, concentrations of HMGB-1 in ischemic and nonischemic lobes, and serum concentrations of TNF-alpha and IL-6 levels were determined in mice. An anti-HMGB-1 antibody treatment was used in SHWI and THIRI to evaluate what aspects of response to ischemia and reperfusion were potentially mediated by HMGB-1. RESULTS: Hepatic HMGB-1 tissue concentrations exhibited biphasic changes in SHWI mice, which were increased in the ischemic lobes relative to nonischemic lobes at 12 h but decreased relative to nonischemic lobes at 24 h after ischemic insult. These results suggested that HMGB-1 was released into the systemic circulation by necrotic cells over the first 12 h but this process may be complete by 24 h postischemia. By 6 to 12 h after SHWI, serum TNF-alpha began to increase significantly and continued to increase for 18 h, followed by a sudden decline. Similarly, serum IL-6 increased over 1-3 h after SHWI and then decreased over the next 6 h. Treatment with an anti-HMGB-1 antibody significantly prolonged survival time in SHWI and THIRI. CONCLUSIONS: HMGB-1 plays a significant role in the response to hepatic ischemia and hepatic ischemia/reperfusion injury. The present study demonstrated a time-dependent production of HMGB-1 following hepatic warm ischemia in mice. The inherent HMGB-1 in ischemic areas was exhausted and HMGB-1 may be released by necrotic cells. HMGB-1 activation is involved in immediate proinflammatory stress response to I/R and anti-HMGB-1 antibody treatment remarkably improved survival. We demonstrated that systemic HMGB-1 accumulation was measured at an earlier phase of the hepatic ischemia and ischemia/reperfusion injury model than LPS-induced endotoxemia.

The persistence of an open anterior fontanel in a 4-year-old girl.

CASE REPORT: A 3-year-old girl was transferred to our hospital with a history of persistent open anterior fontanel. The patient was conscious and had no neurological deficits. Upon arrival, the patient appeared normal for her age and had no defects or anomalies other than the aforementioned lesion. The initial skull X-ray and CT were significant for a 20-mm open anterior fontanel. All other findings were normal. OUTCOME: After a follow-up period of 1.5 years, the anterior fontanel was still open, with a slight decrease in size to 15 mm. Delayed closure of the anterior fontanel without intracranial hypertension is associated with various disorders. The pathogenesis of the current patient's condition is unclear. Due to the patient's normal appearance and stable neurological status, we will follow her conservatively for any changes in condition.

Ductular cell proliferation in islet cell neogenesis induced by incomplete ligation of the pancreatic duct in dogs.

PURPOSE: It has been suggested that islet neogenesis can be induced by incomplete ligation of the pancreatic duct in small animals; however, there has been no report of neogenesis and the proliferation of islets occurring in larger animals. When this procedure was performed in the Vervet monkey, it produced a noticeable increase in duct proliferation, but islet neogenesis was not observed, although the number of monkeys examined was very small. We conducted this study to evaluate whether islet neogenesis and ductular proliferation could be induced in larger animals such as the dog, by partial obstruction of the pancreatic duct. METHODS: Incomplete ligation of the pancreatic duct was induced by tying the pancreas around the ventral side of the head with 2-0 silk and reducing the circumference by about 80% to cause partial obstruction. RESULTS: By 2 weeks after ligation, we saw hyperplasia of the epithelial cells, multilayering of cuboidal cells, and proliferation of ductular cells. The terminal ductules involved in the formation of immunohistochemically insulin-positive islets, and islets, formed adjacent to the alignment of the ductular cells. By 8 weeks after ligation we saw scattered islets, less than 50 micro m in diameter and less than 1 000 microm(2) in area. These cells were immunolabeled for both insulin and cytokeratin, and there was continuity between these insulin-positive cells and terminal ductular cells. Glucagon-positive cells and somatostatin-positive cells were also found adjacent to the alignment of ductular cells. CONCLUSIONS: These results suggest that islets may be differentiated from precursor cells in the pancreatic duct, and that stem cells exist even in adults.

Plasma leptin levels in patients with burn injury: a preliminary report.

The purpose of this study was to investigate the relationship between the plasma leptin level and clinical parameters in patients with burn injury. Six patients with burn injury were admitted to the Emergency and Critical Care Medicine Center of St. Marianna University Hospital within 1h after injury. Plasma levels were monitored for leptin, proinflammatory cytokines (interleukin (IL)-1 beta, IL-6, tumor necrosis factor alpha (TNF alpha)), stress-related parameters (adrenocorticotropic hormone (ACTH), cortisol, and C-reactive protein (CRP)). The change in individual plasma leptin levels did not show similar pattern in all these patients. However, leptin levels remained within the normal range, except in a patient (Case 1) complicated with severe hypovolemic shock. Plasma ACTH and cortisol levels were also elevated in most of the patients. Examination of relationships among plasma leptin, proinflammatory cytokines, and stress-related parameters revealed a significant positive correlation between the plasma leptin level and IL-1 beta or IL-6. These results suggest that the plasma leptin level may have some relations to plasma proinflammatory cytokines in pathophysiologic responses to critical conditions of burn injury.