Involvement of thrombin and mitogen-activated protein kinase pathways in hemorrhagic brain injury

Thrombin is thought to play an important role in brain damage associated with intracerebral hemorrhage (ICH). We previously showed that activation of mitogen-activated protein (MAP) kinases and recruitment of microglia are crucial for thrombin-induced shrinkage of the striatal tissue in vitro and thrombin-induced striatal damage in vivo. Here we investigated whether the same mechanisms are involved in ICH-induced brain injury. A substantial loss of neurons was observed in the center and the peripheral region of hematoma at 3 days after ICH induced by intrastriatal injection of collagenase in adult rats. Intracerebroventricular injection of argatroban or cycloheximide, both of which prevent thrombin cytotoxicity in vitro, exhibited a significant neuroprotective effect against ICH-induced injury. ICH-induced neuron loss was also prevented by a MAP kinase kinase inhibitor (PD98059) and a c-Jun N-terminal kinase inhibitor (SP600125). These drugs had no effect on hematoma size or ICH-induced brain edema. Activation of extracellular signal-regulated kinase in response to ICH was observed in both neurons and microglia. Despite their neuroprotective effects, MAP kinase inhibitors did not decrease the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells appearing after ICH. Identification of cell types revealed that TUNEL staining occurred prominently in neurons but not in microglia, whereas inhibition of MAP kinases resulted in appearance of TUNEL staining in microglia. These results suggest that thrombin and the activation of MAP kinases are involved in ICH-induced neuronal injury, and that neuroprotective effects of MAP kinases are in part mediated by arrestment of microglial activities.     

Serofendic Acid Promotes Stellation Induced by cAMP and cGMP Analogs in Cultured Cortical Astrocytes

We investigated the effect of serofendic acid, a neuroprotective substance derived from fetal calf serum, on the morphological changes in cultured cortical astrocytes. Cultured astrocytes developed a stellate morphology with several processes following exposure to dibutylyl cAMP (dbcAMP), a membrane-permeable cAMP analog; 8-Br-cGMP, a membrane-permeable cGMP analog; or phorbol-12-myristate-13-acetate (PMA), a protein kinase C activator. Serofendic acid significantly accelerated the stellation induced by dbcAMP- and 8-Br-cGMP. In contrast, the PMA-induced stellation was not affected by serofendic acid. Next, we attempted to elucidate the mechanism underlying the dbcAMP-induced stellation and explore the site of action of serofendic acid. Both the stellation induced by dbcAMP and the promotional effect of serofendic acid were partially inhibited by KT5720, a specific protein kinase A (PKA) inhibitor. Furthermore, serofendic acid failed to facilitate the stellation induced by Y-27632, an inhibitor of Rho-associated kinase (ROCK). These results indicate that serofendic acid promotes dbcAMP- and 8-Br-cGMP-induced stellation and the promotional effect on dbcAMP-induced stellation is mediated at least partly by the regulation of PKA activity and not by controlling ROCK activity.     

Lymphatic Microvessel Density is an Independent Prognostic Factor in Colorectal Cancer

Purpose Although lymph node metastasis via lymphatic vessels often is related with an adverse outcome, it is not well known whether lymphatic spread to lymph node needs the development of the new lymphatic formation. In addition, the correlation between lymphangiogenesis and prognosis has not been well documented. This study was designed to assess the prognostic value of lymphangiogenesis and lymphatic vessel invasion in colorectal cancer. Methods We examined 106 colorectal cancer specimens by immunostaining for podoplanin, lymphatic endothelial specific marker. We evaluated lymphangiogenesis, as measured by lymphatic microvessel density, and lymphatic vessel invasion. We next investigated the association of these two parameters with the clinicopathologic findings and prognosis. Results A significant correlation was observed between high lymphatic microvessel density and positive lymphatic vessel invasion (P = 0.0003). Positive lymphatic vessel invasion was significantly associated with the presence of lymph node metastasis (P = 0.0071). The survival curves demonstrated that both high lymphatic microvessel density and positive lymphatic vessel invasion were correlated with an adverse outcome (P = 0.0004 and P = 0.009, respectively). In a univariate analysis, high lymphatic microvessel density and positive lymphatic vessel invasion were negatively associated with the overall survival (P = 0.0011 and P = 0.0118, respectively). Furthermore, high lymphatic microvessel density, but not lymphatic vessel invasion, correlated with a poor outcome in a multivariate analysis (P = 0.0114). Conclusions Our data suggested that lymphatic vessel invasion was related with lymph node metastasis and that both lymphatic microvessel density and lymphatic vessel invasion were related with an adverse outcome in colorectal cancer. Furthermore, lymphatic microvessel density may be a useful prognostic factor in colorectal cancer. *Deceased. The Poster presentation at the meeting of the Japanese Society of Gastroenterology, Sapporo, Japan, October 11 to 14, 2006. Reprints are not available.     

Systemic lupus erythematosus initially manifesting as acute pericarditis complicating with cardiac tamponade : a case report

A 23-year-old woman was admitted with progressive shortness of breath. Echocardiography showed a large volume of pericardial effusion, which indicated cardiac tamponade. Yellowish and puriform fluid with increased white blood cell count (neutrophil dominant) was aspirated, but antibiotics were ineffective. Further examination revealed the presence of positive anti ds-DNA antibody, anti SS-A antibody and anti Sm antibody, resulting in a diagnosis of systemic lupus erythematosus. Her condition was smoothly improved by predonisolone administration. Cardiac tamponade is a rare initial manifestation of systemic lupus erythematosus.     

Administration schedule of daunorubicin for elderly patients with acute myelogenous leukemia: a single-institute experience

We evaluated the efficacy of daunorubicin (40 mg/m(2)/day for 5 days, 200 mg/m(2)/cycle) combined with standard dose of cytarabine (100 mg/m(2)/day for 7 days) for acute myelogenous leukemia patients aged 65-74 years as induction therapy. Complete remission (81.3%) was achieved in 13 of 16 patients following the therapeutic program. The median duration of recovering absolute neutolophilic counts over 1000/μl and platelet counts over 100 000/μl were 33 days and 27 days, respectively. None of the patients had any adverse cardiac complications or died during administration of the induction therapy. Patients achieving complete remission received post-remission therapy consisting of two regimens other than induction therapy. The 3-year disease-free and overall survival rates were 36.9 and 50.0%, respectively. Extending the total period of the daunorubicin therapy might be an alternative to increasing the daily dose of daunorubicin in the induction therapy for elderly patients who were candidates for receiving intensified chemotherapy.     

Functional training for initiating joint attention in children with autism

The present study aimed to examine the controlling variables for initiating joint attention (IJA) in three children with autism. During the baseline, target objects were presented in a location where the child could see them, but the adult could not, and the emergence of IJA was assessed. Children with autism showed some IJA skills during the baseline, but none initiated pointing. In training, the motivating operation for IJA was manipulated by using each child's preferred materials as targets of joint attention. It was found that more frequent and functional joint attention behaviors were emitted following training. The present study suggests that difficulties in IJA in children with autism could be partly explained by restricted interests in children with autism.     

Comparison between monkey and human visual fields using a personal computer system

To use monkeys as models for eye diseases that may lead to blindness, we need to develop a method to precisely measure its visual field and to understand similarities and differences in visual field properties between monkeys and humans. The visual field of monkey was not measured precisely although the necessity. We established a new system with personal computers for precise measurement of the monkey visual field. Four monkeys and three humans served as subjects. The luminance-contrast sensitivity of the central 24 degrees field was measured while the subject was fixating a small spot. During the measurement, we continuously recorded the eye position, and discarded the data when fixation was broken. Reliability indices demonstrated high and stable behavioral performance by both monkeys and humans. The luminance-contrast sensitivity was highest around the fovea, and declined as eccentricity increased. The blind spot was clearly detected 15 degrees temporally. The overall sensitivity was higher in humans than in monkeys and the sensitivity dropped more sharply in the periphery in monkeys than in humans. We recommend this system as a convenient and reliable way to measure visual functions in monkeys in basic ophthalmologic research or in assessment of the drug effects on the visual field.     

Stereotactic radiosurgery for atypical and anaplastic meningiomas

Convection-enhanced delivery (CED) is a local infusion technique, which delivers chemotherapeutic agents directly to the central nervous system, circumventing the blood–brain barrier and reducing systemic side effects. CED distribution is significantly increased if the infusate is hydrophilic. This study evaluated the safety and efficacy of CED of nimustine hydrochloride: 3-[(4-amino-2-methyl-5-pyrimidinyl) methyl]-1-(2-chloroethyl)-1-nitrosourea hydrochloride (ACNU), a hydrophilic nitrosourea, in rat 9 l brain tumor models. The local neurotoxicity of ACNU delivered via CED was examined in normal rat brains, and the maximum tolerated dose (MTD) was estimated at 0.02 mg/rat. CED of ACNU at the MTD produced significantly longer survival time than systemic administration (P < 0.05, log-rank test). Long-term survival (80 days) and eradication of the tumor occurred only in the CED-treated rats. The tissue concentration of ACNU was measured by high-performance liquid chromatography, which revealed that CED of ACNU at the dose of 100-fold less total drug than intravenous injection carried almost equivalent concentrations of ACNU into rat brain tissue. CED of hydrophilic ACNU is a promising strategy for treating brain tumors.