Proposal of patient-specific growth plate cartilage xenograft model for FGFR3 chondrodysplasia.

OBJECTIVE: FGFR3 chondrodysplasia is caused by a gain-of-function mutation of the FGFR3 gene. The disease causes abnormal growth plate cartilage and lacks effective drug treatment. We sought to establish an in vivo model for the study of FGFR3 chondrodysplasia pathology and drug testing. DESIGN: We created cartilage from human induced pluripotent stem cells (hiPSCs) and transplanted the cartilage into the subcutaneous spaces of immunodeficient mice. We then created cartilage from the hiPSCs of patients with FGFR3 chondrodysplasia and transplanted them into immunodeficient mice. We treated some mice with a FGFR inhibitor after the transplantation. RESULTS: Xenografting the hiPSC-derived cartilage reproduced human growth plate cartilage consisting of zones of resting, proliferating, prehypertrophic and hypertrophic chondrocytes and bone in immunodeficient mice. Immunohistochemistry of xenografts using anti-human nuclear antigen antibody indicated that all chondrocytes in growth plate cartilage were human, whereas bone was composed of human and mouse cells. The pathology of small hypertrophic chondrocytes due to up-regulated FGFR3 signaling in FGFR3 skeletal dysplasia was recapitulated in growth plate cartilage formed in the xenografts of patient-specific hiPSC-derived cartilage. The mean diameters of hypertrophic chondrocytes between wild type and thanatophoric dysplasia were significantly different (95% CI: 13.2-26.9; n = 4 mice, one-way analysis of variance (ANOVA)). The pathology was corrected by systemic administration of a FGFR inhibitor to the mice. CONCLUSION: The patient-specific growth plate cartilage xenograft model for FGFR3 skeletal dysplasia indicated recapitulation of pathology and effectiveness of a FGFR inhibitor for treatment and warrants more study for its usefulness to study disease pathology and drug testing.

Mushroom body-preferential expression of proteins/genes involved in endoplasmic reticulum Ca(2+)-transport in the worker honeybee (Apis mellifera L.) brain.

To identify the molecular characteristics specific to the mushroom body (MB, a higher processing centre) neurones in the honeybee brain, we previously used proteomics to identify proteins that are preferentially expressed in these MBs. Here we continued our proteomic analysis to show that reticulocalbin, which is involved in endoplasmic reticulum (ER) Ca(2+) transport, is also preferentially expressed in the MBs in the honeybee brain. Gene expression analysis revealed that reticulocalbin is preferentially expressed in the large-type Kenyon cells, which are MB-intrinsic neurones. In addition, the gene for the ryanodine receptor, which is also involved in ER Ca(2+) transport, was also preferentially expressed in the large-type Kenyon cells. In contrast, the expression of three other ER-related genes, protein disulphide isomerase, sec61 and erp60, was not enriched in the MBs. These findings further support the notion that the function of ER Ca(2+)-signalling, but not the mere intracellular density of ER, is specifically enhanced in the large-type Kenyon cells in the honeybee brain.

Perfusion index derived from a pulse oximeter can predict the incidence of hypotension during spinal anaesthesia for Caesarean delivery.

BACKGROUND: Hypotension during spinal anaesthesia for Caesarean delivery is a result of decreased vascular resistance due to sympathetic blockade and decreased cardiac output due to blood pooling in blocked areas of the body. Change in baseline peripheral vascular tone due to pregnancy may affect the degree of such hypotension. The perfusion index (PI) derived from a pulse oximeter has been used for assessing peripheral perfusion dynamics due to changes in peripheral vascular tone. The aim of this study was to examine whether baseline PI could predict the incidence of spinal anaesthesia-induced hypotension during Caesarean delivery. METHODS: Parturients undergoing elective Caesarean delivery under spinal anaesthesia with hyperbaric bupivacaine 10 mg and fentanyl 20 µg were enrolled in this prospective study. The correlation between baseline PI and the degree of hypotension during spinal anaesthesia and also the predictability of spinal anaesthesia-induced hypotension during Caesarean delivery by PI were investigated. RESULTS: Baseline PI correlated with the degree of decreases in systolic and mean arterial pressure (r=0.664, P<0.0001 and r=0.491, P=0.0029, respectively). The cut-off PI value of 3.5 identified parturients at risk for spinal anaesthesia-induced hypotension with a sensitivity of 81% and a specificity of 86% (P<0.001). The change of PI in parturients with baseline PI ≤ 3.5 was not significant during the observational period, while PI in parturients with baseline PI>3.5 demonstrated marked decreases after spinal injection. CONCLUSIONS: We demonstrated that higher baseline PI was associated with profound hypotension and that baseline PI could predict the incidence of spinal anaesthesia-induced hypotension during Caesarean delivery.

Elevated expression of protease-activated receptor 1 via ΔNp63 down-regulation contributes to nodal metastasis in oral squamous cell carcinoma.

Protease-activated receptor 1 (PAR1) is known as a thrombin receptor. Recent studies have reported PAR1 expression in various malignancies; however, its role in oral squamous cell carcinoma (OSCC) requires clarification. A previous study showed that down-regulation of ΔNp63, a homolog of p53, augments PAR1 expression in OSCC. In the present study, the association of PAR1 expression with clinicopathological findings in OSCC was examined retrospectively. Expression of PAR1, thrombin, and ΔNp63 was examined immunohistochemically in OSCC specimens. Patients were divided into three groups based on the expression pattern of PAR1 at the invasive front: group A, PAR1-negative in both cancer and stromal cells; group B, positive in stromal cells but negative in cancer cells; group C, positive in both cancer and stromal cells. Histologically high-grade tumours were significantly more common in group C. Patients in group C had the highest incidence rate of nodal metastasis (P<0.001) and a lower survival rate (P=0.085) than those in the other groups. At the invasive front, in group C, thrombin was expressed but ΔNp63 expression was weak. These results indicate that increased PAR1 expression in both cancer and stromal cells could be a useful predictive marker of nodal metastasis and that ΔNp63 is involved in regulating PAR1 expression.

A full-length cDNA resource for the pea aphid, Acyrthosiphon pisum.

Large collections of full-length cDNAs are important resources for genome annotation and functional genomics. We report the creation of a collection of 50 599 full-length cDNA clones from the pea aphid, Acyrthosiphon pisum. Sequencing from 5' and 3' ends of the clones generated 97 828 high-quality expressed sequence tags, representing approximately 9000 genes. These sequences were imported to AphidBase and are shown to play crucial roles in both automatic gene prediction and manual annotation. Our detailed analyses demonstrated that the full-length cDNAs can further improve gene models and can even identify novel genes that are not included in the current version of the official gene set. This full-length cDNA collection can be utilized for a wide variety of functional studies, serving as a community resource for the study of the functional genomics of the pea aphid.

A clinical investigation of the association between perioperative oral management and prognostic nutritional index in patients with digestive and urinary cancers.

Background: The prognostic nutritional index (pni) is a simple metric calculated using serum albumin and the peripheral lymphocyte count. It was reported that a low pni score is significantly associated with major postoperative complications and poor prognosis. The purpose of the present study was to investigate the effects of perioperative oral management (pom) on the perioperative pni profiles of patients with digestive system or urinary cancers. Study Design: The medical records of 181 patients with cancer who underwent surgery and for whom a pni could be calculated were retrospectively reviewed. Results: The intervention rate with pom was 34.8%. The median preoperative pni score was 48.25 in all patients with a pom intervention [25% to 75% interquartile range (iqr): 44.38-54.13] and 47.25 in those without an intervention (iqr: 42.0-53.5). Compared with patients not receiving pom, those who received pom had significantly higher pni scores from the early postoperative period (p < 0.05). Notably, of patients who could resume oral intake within 3 days after surgery, those who received pom intervention, compared with those who did not, had significantly higher pni scores from the early postoperative period (p < 0.05). Conclusions: Perioperative oral management interventions might have positive effects on the postoperative pni scores of patients with cancer.

Determination of Lycopene Concentration in Fresh Tomatoes by Spectrophotometry: A Collaborative Study.

BACKGROUND: Lycopene has been the object of considerable research attention recently, and the effects of the intake of lycopene, or of tomato products, have been studied in various ways. In Japan, interest in the health-promoting function of food components has increased. OBJECTIVE: Developing a method to determine lycopene contents in tomato that meets the Japanese Agricultural Standard (JAS). METHOD: In the proposed JAS method, the test sample consists of fresh tomatoes; a hexane-acetone mixture is utilized as the extraction solvent. A collaborative study was conducted to evaluate the interlaboratory performance of the method. RESULTS: Ten laboratories participated and analyzed six test materials characterized by a lycopene content between 39 and 170 mg/kg as blind duplicates. After removing statistical outliers, RSDr ranged from 1.2 to 3.0% and RSDR ranged from 2.4 to 4.2%. The HorRat values were calculated and found to be in the 0.26-0.49 range. CONCLUSIONS: The method for determining the lycopene content in tomato was evaluated by means of a collaborative study, and the reproducibility of this method was found to be acceptable. HIGHLIGHTS: Intended for standardization in Japan, a method to determine lycopene content in tomato has been developed and shown to have acceptable precision in a collaborative study.

Salvage surgery for a locally persistent or recurrent tumour in maxillary cancer patients who have undergone radiotherapy and concomitant intra-arterial cisplatin: implications for surgical margin assessment.

Limited information about salvage surgery is available for locally persistent and recurrent maxillary sinus cancers after the completion of chemoradiation therapy. Seventy-six maxillary sinus cancer patients who had undergone chemoradioselection using initial radiotherapy and concomitant intra-arterial cisplatin were screened retrospectively. Twenty-four of these patients who had a locally persistent or recurrent tumour were investigated. The 2-year overall survival rate of patients with maxillary sinus cancer of all types was 39.0% for those who underwent salvage surgery and 10.0% for those who did not. The 2-year overall survival rate of patients with maxillary sinus squamous cell carcinoma was 45.8% for those who underwent salvage surgery and 11.1% for those who did not. Furthermore, the 2-year local control and overall survival rates of patients with positive and negative surgical margins were 14.3% and 83.3% and 14.3% and 66.7%, respectively. There were significant differences in local control (P=0.004) and overall survival (P=0.005) regarding surgical margin status. Although salvage surgery for a locally persistent or recurrent maxillary sinus cancer is a feasible treatment, patients with positive surgical margins are more prone to local relapse. Therefore, surgical safety margins should be assessed thoroughly.

Bis(1-oxy-2-pyridinethiolato)oxovanadium(IV) enhances neurogenesis via phosphatidylinositol 3-kinase/Akt and extracellular signal regulated kinase activation in the hippocampal subgranular zone after mouse focal cerebral ischemia.

Although neurogenesis in the hippocampus is critical for improvement of depressive behaviors and cognitive functions in neurodegeneration disorders, there is no therapeutic agent available to promote neurogenesis in adult brain following brain ischemic injury. Here we found that i.p. administration of bis(1-oxy-2-pyridinethiolato)oxovanadium(IV) [VO(OPT)], which stimulates phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal regulated kinase (ERK) pathways, markedly enhanced brain ischemia-induced neurogenesis in the subgranular zone (SGZ) of the mouse hippocampus. VO(OPT) treatment enhanced not only the number of proliferating cells but also migration of neuroblasts. VO(OPT)-induced neurogenesis was associated with Akt and ERK activation in neural precursors in the SGZ. Likewise, VO(OPT)-induced neurogenesis was blocked by both PI3K/Akt and mitogen-activated protein kinase/extracellular signal regulated kinase kinase (MEK)/ERK inhibitors. VO(OPT) treatment rescued decreased phosphorylation of glycogen synthesis kinase 3beta (GSK-3beta) at Ser-9. Finally, amelioration of cognitive dysfunction seen following brain ischemia was positively correlated with VO(OPT)-induced neurogenesis. Taken together, VO(OPT) is a potential therapeutic agent that enhances ischemia-induced neurogenesis through PI3K/Akt and ERK activation, thereby improving memory and cognitive deficits following brain ischemia.

Spontaneous resolution of isolated dissecting aneurysm on the posterior inferior cerebellar artery.

The authors report a rare example of an isolated dissecting posterior inferior cerebellar artery (PICA) aneurysm with spontaneous resolution. A 41 year-old male suffered sudden dizziness, nausea and vomiting. An angiogram and magnetic resonance imaging (MRI) detected an isolated PICA dissection. The patient was treated conservatively and recovered without any apparent neurological deficit. MRI detected the self-resolution of the dissecting aneurysm. Dissecting PICA aneurysms, especially non-haemorrhagic lesions, have the possibility of spontaneous resolution resulting in a favorable outcome. The treatment strategy for this vascular lesion may be decided based upon neuroradiological changes on careful follow-up.

Multiple peripheral middle cerebral artery aneurysms associated with Behcet's disease.

We report a 19-year-old woman with Behcet's disease who suffered a subarachnoid hemorrhage and had bilateral peripheral middle cerebral artery aneurysms. After steroid therapy for 3 days, the smaller aneurysm disappeared. The larger aneurysm was excised and the artery reconstructed using a superficial temporary artery graft. Histological examination showed vasculitis restricted to the wall of the aneurysm. This is the first report of arterial reconstruction for an aneurysm associated with Behcet's disease. Steroid therapy before the operation may facilitate repair of the arterial wall.

Clinical evaluation of cellulose porous beads for the therapeutic embolization of meningiomas.

BACKGROUND AND PURPOSE: Cellulose porous beads (CPBs) are a new, exceptionally uniformly sized, nonabsorbable embolic agent. We evaluated their efficacy in the preoperative embolization of meningiomas. METHODS: In 141 consecutive patients, we used CPBs (200-microm diameter) for the preoperative embolization of meningiomas. We selected patients whose tumors were > or =4 cm with 50% of blood to the tumor supplied by the external carotid artery (ECA). All patients underwent a provocation test before embolization. The percentage of blood supplied to the tumor by the internal carotid artery and ECA was determined angiographically. Nonenhanced areas on postembolization MR imaging were calculated. Intraoperative blood loss, units of blood transfusion, and hemostasis at the time of surgery were recorded for each patient. The interval between embolization and surgery was intentionally longer than 7 days. RESULTS: Of the 141 patients, 128 underwent CBP embolization. Eleven patients had positive provocation test results, and 2 had vasospasm; they were not CBP embolized. In 72% of the patients CBP embolization achieved reduction in the flow of the feeding artery by more than 50%. The nonenhanced area on MR imaging was not significantly correlated with the degree of ECA supply or devascularization. The interval between embolization and surgery was 8-26 days (mean, 9.9 days). The longer this interval, the greater was the tumor-softening effect and the rate of tumor removal. CONCLUSIONS: CPBs may be useful for the preoperative embolization of meningiomas. To increase the efficacy of CPB embolization, the interval to surgery should be at least 7 days.

Potential role of calcineurin for brain ischemia and traumatic injury.

Calcineurin belongs to the family of Ca2+/calmodulin-dependent protein phosphatase, protein phosphatase 2B. Calcineurin is the only protein phosphatase which is regulated by a second messenger, Ca2+. Furthermore, calcineurin is highly localized in the central nervous system, especially in those neurons vulnerable to ischemic and traumatic insults. For these reasons, calcineurin is considered to play important roles in neuron-specific functions. Recently, on the basis of the finding that FK506 and cyclosporin A serve as calcineurin-specific inhibitors, this enzyme has become the subject of much study. It is clear that calcineurin is involved in many neuronal (or non-neuronal) functions such as neurotransmitter release, regulation of receptor functions, signal transduction systems, neurite outgrowth, gene expression and neuronal cell death. In this review, we describe the calcineurin functions, functions of the substrates, and the pathogenesis of traumatic and ischemic insults, and we discuss the potential role of calcineurin. There are many similarities in traumatic and ischemic pathogenesis of the brain in which the release of excessive glutamate is followed by an intracellular Ca2+ increase. However, the intracellular cascade which leads to neuronal cell death after the release of excess Ca2+ is unclear. Although calcineurin is thought to be a key toxic enzyme on the basis of studies using immunosuppressants (FK506 or cyclosporin A), many of the functions of the substrates for calcineurin protect against neuronal cell death. We concluded that calcineurin is a bi-directional enzyme for neuronal cell death, having protective and toxic actions, and the balance of the bi-directional effects may be important in ischemic and traumatic pathogenesis.

High durability cementitious material with mineral admixtures and carbonation curing.

Nuclear waste repositories need highly durable cementitious materials to function for over thousands of years while resisting leaching and degradation. The durability of cementitious material can be effectively improved by reducing permeability and by changing cement hydrates to a less soluble matrix. This paper describes the properties of carbonated new cementitious materials containing belite-rich cement and gamma-2CaO.SiO2 as main components. In addition, the long-term leaching properties are investigated and compared with ordinary Portland cement by using a predictive leaching model.

Expression of angiopoietin-2 in human glioma cells and its role for angiogenesis.

In highly vascular malignant glioma, glioma cells themselves may express angiogenic factors and induce angiogenesis. Recent studies have shown that novel angiogenic factors, angiopoietin-1 (Ang1) and -2 (Ang2), play important roles in the modulation of vasculogenesis and angiogenesis. In this study, we determined Ang2 mRNA expression in cultured human malignant glioma cells (U105, U251, and U373 MG) by reverse transcriptase-PCR. Western blot analysis and immunocytochemical analysis with antihuman Ang2 antibody revealed that Ang2 protein was expressed and secreted by these cells. Furthermore, hypoxia increased the Ang2 protein level in cultured glioma cells. Serial sections of 32 human glioma tissues (14 glioblastomas, eight anaplastic astrocytomas, seven astrocytomas, and three pilocytic astrocytomas) were immunostained against Ang2, vascular endothelial growth factor, Tie2, von Willebrand factor, and alpha smooth muscle actin. The immunoreactivity of each angiogenic factor was higher in malignant gliomas than in low-grade gliomas. Ang2 protein was detected not only in endothelial cells but also in glioma cells, and its expression was prominent in both the area surrounding the necrosis and the periphery of glioblastomas. In the area surrounding necrosis, Ang2 was highly expressed and tumor vessels showed regression. In the tumor periphery, Ang2 was highly expressed and many small vessels stained positively for von Willebrand factor but not for alpha smooth muscle actin, suggesting angiogenesis. Statistical analysis revealed that the Ang2 expression was negatively correlated with vessel maturation in malignant gliomas and that vascular endothelial growth factor expression was positively correlated with vessel maturation in low-grade gliomas (P < 0.05). These results suggest that glioma cells themselves express Ang2 and that expression may be induced by hypoxic stimulation and may play a crucial role in the vessel maturation, angiogenesis, and vessel regression in malignant glioma.

Regression of gastric de novo diffuse large B-cell lymphoma following Helicobacter pylori eradication: a case report.

We report a case of primary gastric diffuse large B-cell lymphoma (DLBCL), de novo DLBCL without the features of mucosa-associated lymphoid tissue (MALT) lymphoma, which regressed after Helicobacter pylori (HP) eradication. A 27-year-old Japanese female with epigastralgia was revealed to have ulcerated lesions in the angle and antral regions on gastroscopy. Biopsy specimen was consistent with a diagnosis of DLBCL without MALT lymphoma component, indicating de novo development. Her clinical staging on the Lugano system was Stage I. HP was positive on a rapid urease test, and she received HP eradication therapy twice, because the first therapy was not successful. On gastroscopy performed 1 month after the second HP eradication therapy, no ulcerated lesion was noted, and the lymphoma cells had regressed histopathologically. (Acta gastro-enterol. belg., 2016, 79, 367-369A).

Ischemia-induced neuronal cell death is mediated by the endoplasmic reticulum stress pathway involving CHOP.

Brain ischemia induces apoptosis in neuronal cells, but the mechanism is not well understood. When wild-type mice were subjected to bilateral common carotid arteries occlusion (BCCAO) for 15 min, apoptosis-associated morphological changes and appearance of TUNEL-positive cells were observed in the striatum and in the hippocampus at 48 h after occlusion. RT-PCR analysis revealed that mRNAs for ER stress-associated proapoptotic factor CHOP and an ER chaperone BiP are markedly induced at 12 h after BCCAO. Immunohistochemical analysis showed that CHOP protein is induced in nuclei of damaged neurons at 24 h after occlusion. In contrast, ischemia-associated apoptotic loss of neurons was decreased in CHOP(-/-) mice. Primary hippocampal neurons from CHOP(-/-) mice were more resistant to hypoxia-reoxygenation-induced apoptosis than those from wild-type animals. These results indicate that ischemia-induced neuronal cell death is mediated by the ER stress pathway involving CHOP induction.

Microcatheter intrathecal urokinase infusion into cisterna magna for prevention of cerebral vasospasm: preliminary report.

BACKGROUND AND PURPOSE: The feasibility of preventing vasospasm by intrathecal anterograde infusion of urokinase (UK) into the cisterna magna was studied in patients with recently ruptured aneurysms who had just undergone the placement of a Guglielmi detachable coil (GDC). METHODS: Immediately after complete embolization with the use of GDC-10 coils, 15 patients with Hunt and Hess neurological grades III and IV received 60 000 IU of UK in normal saline through a microcatheter advanced into the cisterna magna. UK infusion was repeated once or twice over a period of 2 to 3 days according to a decision based on CT evidence of a subarachnoid clot remaining in the cisterns. Before administering the last UK infusion, we obtained CT confirmation of almost complete clearance of clots in the basal cisterns. RESULTS: In all 15 patients, the microcatheter was advanced easily into the cisterna magna by use of the over-the-wire microcatheter technique. In 8 patients who received thrombolytic therapy within 24 hours of the ictus, there was almost complete clearance of the clot in the basal cisterns within 2 days of suffering the insult. When UK was injected at 24 to 48 hours after the insult, 7 patients manifested CT evidence of clearance at the latest 4 days after suffering the insult. In all 15 patients, CT scans obtained within 24 hours of the final UK administration showed complete resolution of clots in the basal cistern and almost complete resolution of clots in the basal interhemispheric fissure and bilateral proximal sylvian fissures. Although one patient developed a transient neurological deficit, no patients manifested permanent delayed neurological deficits as a result of vasospasm. Outcome assessment according to the Glasgow Outcome Scale, no less than 3 months after GDC placement, revealed good recovery in all patients, and none developed hydrocephalus requiring a shunt procedure. CONCLUSIONS: In patients with recently ruptured aneurysms, GDC placement followed by immediate intrathecal administration of UK from the cisterna magna may be a safe and reasonable means of preventing vasospasms and may result in improved treatment outcomes.

Neuroprotective effect of sodium orthovanadate on delayed neuronal death after transient forebrain ischemia in gerbil hippocampus.

In transient forebrain ischemia, sodium orthovanadate as well as insulinlike growth factor-1 (IGF-1) rescued cells from delayed neuronal death in the hippocampal CA1 region. Adult Mongolian gerbils were subjected to 5-minute forebrain ischemia. Immunoblotting analysis with anti-phospho-Akt/PKB (Akt) antibody showed that phosphorylation of Akt at serine-473 (Akt-Ser-473) in the CA1 region decreased immediately after reperfusion, and in turn transiently increased 6 hours after reperfusion. The decreased phosphorylation of Akt-Ser-473 was not observed in the CA3 region. The authors then tested effects of intraventricular injection of orthovanadate and IGF-1, which are known to activate Akt. Treatment with orthovanadate or IGF-1 30 minutes before ischemia blocked delayed neuronal death in the CA1 region. The neuroprotective effects of orthovanadate and IGF-1 were associated with preventing decreased Akt-Ser-473 phosphorylation in the CA1 region observed immediately after reperfusion. Immunohistochemical studies with the anti-phospho-Akt-Ser-473 antibody also demonstrated that Akt was predominantly in the nucleus and was moderately activated in the cell bodies and dendrites of pyramidal neurons after orthovanadate treatment. The orthovanadate treatment also prevented the decrease in phosphorylation of mitogen-activated protein kinase (MAPK). Pretreatment with combined blockade of phosphatidylinositol 3-kinase and MAPK pathways totally abolished the orthovanadate-induced neuroprotective effect. These results suggest that the activation of both Akt and MAPK activities underlie the neuroprotective effects of orthovanadate on the delayed neuronal death in the CA1 region after transient forebrain ischemia.

Activation of Akt/protein kinase B contributes to induction of ischemic tolerance in the CA1 subfield of gerbil hippocampus.

Apoptosis plays an important role in delayed neuronal cell death after cerebral ischemia. Activation of Akt/protein kinase B has been recently reported to prevent apoptosis in several cell types. In this article the authors examine whether induction of ischemic tolerance resulting from a sublethal ischemic insult requires Akt activation. Sublethal ischemia gradually and persistently stimulated phosphorylation of Akt-Ser-473 in the hippocampal CA1 region after reperfusion. After lethal ischemia, phosphorylation of Akt-Ser-473 showed no obvious decrease in preconditioned gerbils but a marked decrease in nonconditioned gerbils. Changes in Akt-Ser-473 phosphorylation were correlated with changes in Akt activities, as measured by an in vitro kinase assay. Intracerebral ventricular infusion of wortmannin before preconditioning blocked both the increase in Akt-Ser-473 phosphorylation in a dose-dependent manner and the neuroprotective action of preconditioning. These results suggest that Akt activation is induced by a sublethal ischemic insult in gerbil hippocampus and contributes to neuroprotective ischemic tolerance in CA1 pyramidal neurons.