Thrombin induces striatal neurotoxicity depending on mitogen-activated protein kinase pathways in vivo

Intracerebral hemorrhage represents stroke characterized by formation and expansion of hematoma within brain parenchyma. Blood-derived factors released from hematoma are considered to be involved in poor prognosis of this disorder. We previously reported that thrombin, a blood-derived serine protease, induced cytotoxicity in the cerebral cortex and the striatum in organotypic slice cultures, which depended on mitogen-activated protein kinase (MAPK) pathways. Here we investigated the mechanisms of thrombin cytotoxicity in the striatum in vivo. Thrombin microinjected into the striatum of adult rats induced neuronal death and microglial activation around the injection site. Neuronal loss without any sign of nuclear fragmentation was observed as early as 4 h after thrombin injection, which was followed by gradual neuronal death exhibiting nuclear fragmentation. Thrombin-induced damage assessed at 72 h after injection was partially but significantly reduced by concomitant administration of inhibitors of MAPK pathways. Activation of extracellular signal-regulated kinase (ERK) and p38 MAPK in response to thrombin was verified by Western blot analysis. Moreover, phosphorylated ERK and p38 MAPK were localized prominently in reactive microglia, and inhibition of microglial activation by minocycline attenuated thrombin-induced damage, suggesting that reactive microglia were responsible for thrombin-induced neuronal death. Thus, MAPK pathways and microglial activation may serve as therapeutic targets of pathogenic conditions associated with hemorrhagic stroke.

Synergistic effects of injection of bone marrow cells into both portal vein and bone marrow on tolerance induction in transplantation of allogeneic pancreatic islets

We have established a new method for allogeneic pancreatic islet (PI) transplantation: relatively low doses of irradiation followed by simultaneous transplantation of PIs and bone marrow cells (BMCs) via the portal vein (PV). In the present study, we have compared this method with intra-bone marrow (IBM)-bone marrow transplantation (BMT), and with a combination of both methods. Streptozotocin (STZ)-induced diabetic-recipient rats, Fischer 344 (F344, RT1A(l), RT1B(l)), were irradiated 1 day before transplantation. PIs of Brown Norway rats (BN, RT1A(n), RT1B(n)) were transplanted into the liver of the diabetic F344 rats via the PV. BMCs from BN rats were injected into the recipients' bone marrow (IBM), PV or intravenously (IV) or by a simultaneous combination of PV plus IBM (PV+IBM). We compared graft survival among the groups of '9 Gy+IBM'(10/10 accepted), '9 Gy+PV'(7/10 accepted), '9 Gy+IV'(0/7 accepted), '9 Gy+PV+IBM'(8/8 accepted), '8.5 Gy+IBM'(4/9 accepted), '8.5 Gy+PV'(0/7 accepted), '8.5 Gy+IV'(0/7 accepted), '8.5 Gy+PV+IBM'(9/12 accepted), '8 Gy+IBM'(2/10 accepted) and '8 Gy+PV+IBM'(2/8 accepted). As we reported previously, PV-BMT is more effective in inducing the acceptance of allogeneic PIs than IV-BMT. However, IBM-BMT requires less pretreatment than PV-BMT. (PV+IBM)-BMT was found to be the most effective in inducing the acceptance of allogeneic PIs. These results suggest that allogeneic PI-transplantation in conjunction with (PV+IBM)-BMT could become a viable strategy.

Diffusion MRI abnormalities after prolonged febrile seizures with encephalopathy

BACKGROUND

Patients with encephalopathy heralded by a prolonged seizure as the initial symptom often have abnormal subcortical white matter on diffusion-weighted MRI (DWI).

OBJECTIVE

To determine if these patients share other common features.

METHODS

Patients with encephalopathy heralded by a prolonged seizure and followed by the identification of abnormal subcortical white matter on MRI were collected retrospectively. Their clinical, laboratory, and radiologic data were reviewed.

RESULTS

Seventeen patients were identified, ages 10 months to 4 years. All had a prolonged febrile seizure (longer than 1 hour in 12 patients) as their initial symptom. Subsequent seizures, most often in clusters of complex partial seizures, were seen 4 to 6 days after the initial seizure in 16 patients. Outcome ranged from almost normal to severe mental retardation. MRI performed within 2 days of presentation showed no abnormality. Subcortical white matter lesions were observed on DWI between 3 and 9 days in all 17 patients. T2-weighted images showed linear high intensity of subcortical U fibers in 13 patients. The lesions were predominantly frontal or frontoparietal in location with sparing of the perirolandic region. The diffusion abnormality disappeared between days 9 and 25, and cerebral atrophy was detected later than 2 weeks. Three patients having only frontal lesions had relatively good clinical outcome.

CONCLUSIONS

Although the pathophysiologic mechanism remains unknown, these patients seem to have a distinctive encephalopathy syndrome. MRI is helpful in establishing the diagnosis of this encephalopathy.

Helicobacter pylori outer membrane proteins and gastroduodenal disease

BACKGROUND AND AIMS

A number of Helicobacter pylori outer membrane proteins (OMPs) undergo phase variations. This study examined the relation between OMP phase variations and clinical outcome.

METHODS

Expression of H pylori BabA, BabB, SabA, and OipA proteins was determined by immunoblot. Multiple regression analysis was performed to determine the relation among OMP expression, clinical outcome, and mucosal histology.

RESULTS

H pylori were cultured from 200 patients (80 with gastritis, 80 with duodenal ulcer (DU), and 40 with gastric cancer). The most reliable results were obtained using cultures from single colonies of low passage number. Stability of expression with passage varied with OipA > BabA > BabB > SabA. OipA positive status was significantly associated with the presence of DU and gastric cancer, high H pylori density, and severe neutrophil infiltration. SabA positive status was associated with gastric cancer, intestinal metaplasia, and corpus atrophy, and negatively associated with DU and neutrophil infiltration. The Sydney system underestimated the prevalence of intestinal metaplasia/atrophy compared with systems using proximal and distal corpus biopsies. SabA expression dramatically decreased following exposure of H pylori to pH 5.0 for two hours.

CONCLUSIONS

SabA expression frequently switched on or off, suggesting that SabA expression can rapidly respond to changing conditions in the stomach or in different regions of the stomach. SabA positive status was inversely related to the ability of the stomach to secrete acid, suggesting that its expression may be regulated by changes in acid secretion and/or in antigens expressed by the atrophic mucosa.

L-arginine improves the symptoms of strokelike episodes in MELAS

Based on the hypothesis that mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS) are caused by impaired vasodilation in an intracerebral artery, the authors evaluated the effects of administering l-arginine, a nitric oxide precursor. Patients were administered L-arginine intravenously at the acute phase or orally at the interictal phase. L-arginine infusions significantly improved all strokelike symptoms, suggesting that oral administration within 30 minutes of a stroke significantly decreased frequency and severity of strokelike episodes.

Antiplatelet therapy contributes to acute deterioration of intracerebral hemorrhage

OBJECTIVE

The purpose of this study was to examine the effect of antiplatelet therapy on the initial severity and the acute outcome of intracerebral hemorrhage (ICH).

METHODS

The authors reviewed records of 251 consecutive patients hospitalized in their cerebrovascular center within 24 hours after onset of ICH.

RESULTS

Fifty-seven patients (23%) had development of ICH during oral antiplatelet therapy. The major indication for antiplatelet therapy was the prevention of stroke recurrence (63%). As compared with patients without antiplatelet therapy, those who received antiplatelet therapy more frequently were aged 70 years or older (60% vs 35%; p < 0.001), had previous symptomatic ischemic stroke (54% vs 7%; p < 0.0001), had diabetes mellitus (26% vs 15%; p < 0.05), and had heart disease (32% vs 8%; p < 0.0001). Antiplatelet therapy was predictive of an increase in the hematoma volume by more than 40% on the second hospital day (hematoma enlargement, odds ratio [OR] 7.67, 95% CI 1.62 to 36.4) and the need for emergent surgical evacuation of the hematoma (OR 3.10, 95% CI 1.18 to 8.15). Antiplatelet therapy was an independent predictor for the occurrence of any of hematoma enlargement, emergent death, or evacuation surgery, which suggests that clinical deterioration occurs into the second hospital day (OR 7.45, 95% CI 2.46 to 22.5).

CONCLUSIONS

Antiplatelet therapy seems to contribute to the acute clinical deterioration of intracerebral hemorrhage.

Prediction of cerebral blood flow restoration after extracranial-intracranial bypass surgery using superficial temporal artery duplex ultrasonography (STDU)

We investigated the availability of superficial temporal artery (STA) duplex ultrasonography (STDU) for evaluating the improvement of cerebral hemodynamics after extracranial-intracranial (EC-IC) bypass. This study included 56 consecutive patients who underwent EC-IC bypass for occlusive disease of their cerebral arteries. STA duplex ultrasonography (STDU) was performed to measure the flow velocity, pulsatility index, and diameter of ipsilateral STA before and 14 days after EC-IC bypass. Regional cerebral blood flow (rCBF) and acetazolamide (ACZ) reactivity of ipsilateral MCA territory were evaluated by quantitative single photon emission computed tomography. The mean flow velocities of ipsilateral STA were significantly higher (p < 0.0001) and PI value was significantly lower (p < 0.0001) 14 days after EC-IC bypass than before. The diameter of ipsilateral STA was also larger 14 days after EC-IC bypass than before (p < 0.0001). STA mean flow velocity was significantly correlated with the rCBF 14 days after EC-IC bypass (R = 0.55, p < 0.0001). The post-surgical STA mean flow velocity cut-off value over 58.2 cm/sec yielded the highest diagnostic accuracy (sensitivity, 75%; specificity, 74%) for excellent rCBF value (> or =40 ml/100 g/min) after EC-IC bypass. The ipsilateral STA mean blood flow velocity is a highly sensitive parameter for predicting rCBF in the ipsilateral MCA territory after EC-IC bypass.

Promising survival for patients with glioblastoma multiforme treated with individualised chemotherapy based on in vitro drug sensitivity testing

We retrospectively investigated the efficacy and feasibility of individualised chemotherapy based on in vitro drug sensitivity testing (DST) for patients with glioblastoma multiforme. A total of 40 consecutive patients with glioblastoma multiforme (GM) were enrolled into this study between January 1995 and December 2000. The flow cytometric (FCM) detection of apoptosis was used to determine the in vitro sensitivity of tumour cells obtained at surgery to 30 different kinds of anticancer agents. From the results of FCM assay, an in vitro best regimen was prospectively selected. All the patients concurrently received the individualised chemotherapy with the in vitro best regimen and 60 Gy of conventional radiation therapy. Of the 31 assessable patients, eight patients (26%) achieved partial response, and 20 patients (65%) had stable disease. The median survival time was 20.5 months. The individualised chemotherapy based on in vitro DST was associated with favourable survival time for the patients with GM compared with the reported results of conventional therapy regimens. The present result suggests that the currently available anticancer agents could be effective against GM when used in individualised chemotherapy.

Expression of enzyme associated with steroid hormone synthesis and local production of steroid hormone in endometrial carcinoma cells

Endometrial carcinoma is a common malignancy of the genital tract. In the present study, we examined the expression of human steroidogenic acute regulatory (StAR) protein, P450 side-chain cleavage enzyme (P450 scc), 17alpha-hydroxylase/17,20-desmolase (P45017alpha) and aromatase (P450 arom) in endometrial carcinoma cells to clarify the ability of these cells to produce steroid hormones. The results of RT-PCR analysis showed that StAR, P450 scc and P45017alpha genes were expressed in endometrial carcinoma cells. To examine the protein expression of StAR and P450 scc, we performed Western blotting using extracts from carcinoma cells. StAR protein and P450 scc were detected in both HHUA and HOUA-1 cells. The production of pregnenolone in HHUA cells increased 2.4-fold with transfection of a StAR expression vector and 4.3-fold with transfection of an F2 side-chain cleavage system. The RT-PCR product of 3beta-hydroxysteroid dehydrogenase was present in endometrial carcinoma cells. In endometrial carcinoma cells, the production of progesterone also increased with over-expression of StAR and the F2 system. Results of steroid metabolic assays showed that endometrial carcinoma cells produced not only 17alpha-hydroxyprogesterone but also androstenedione. Endometrial carcinoma cells express enzymes that are associated with the production of steroid hormones. Locally produced steroid hormones may have effects on tumor proliferation and tumorigenesis.

Effects of an aldose reductase inhibitor on gastroenteropathy in streptozotocin-diabetic rats

We investigated the effects of epalrestat, an aldose reductase inhibitor (ARI), on gastric emptying, fecal water content, and electrolyte transport in distal colon in streptozotocin (STZ)-induced diabetic rats. We measured gastric emptying time by acetaminophen method and short-circuit-current (Isc) in colonic mucosa using an Ussing chamber. The Isc in response to electric-field-stimulation (EFS) was decreased in untreated rats due to suppression by Cl- secretion. ARI treatment alleviated this suppression (2.7 +/- 0.6 vs. 7.4 +/- 1.1 microA/0.38 cm2 at 8 weeks after treatment, 1.1 +/- 0.2 vs. 7.0 +/- 1.0 at 12 weeks after treatment, P<0.05). In addition, the percentage of fecal water content in untreated rats was significantly lower than in ARI-treated rats (58.0 +/- 2.0 vs. 67.6 +/- 0.8% at 8 weeks, 56.9 +/- 2.1 vs. 63.4 +/- 1.4 at 12 weeks, P<0.05). From STZ injection to 8 weeks, the serum levels of acetaminophen in the diabetic rats were significantly lower than in controls, indicating delayed gastric emptying. At 12 weeks in the diabetic rats treated with ARI, the serum levels of acetaminophen were significantly higher than in the untreated diabetic rats (6.6 +/- 0.4 vs. 3.5 +/- 0.5 microg/ml, P<0.05). ARI-treatment ameliorated delayed gastric emptying without improving glycemic control. These findings show that ARI partially prevented progression of impaired gastric emptying, ion transport, and water transport, and suggest that epalrestat might be useful in the treatment of diabetic gastroenteropathy.

CYP1A1 polymorphism and risk of gynecological malignancy in Japan

The incidence of endometrial cancer and ovarian cancer in Japan has been increasing in recent years. Results of epidemiologic studies suggest that the onset and multiplication of these cancers are associated with estrogen. Estrogens are metabolized by cytochrome P450 1A1 (CYP1A1) and converted into catecholestrogens, which are carcinogens. CYP1A1 has several polymorphisms, the major one being T6235C transition in the non-coding 3'-flanking region (MspI polymorphism), and another being A4889G transition in exon 7 (Ile/Val polymorphism). These polymorphisms can affect the metabolites of estrogens and contribute to the susceptibility to gynecological malignancy. In this study, to determine whether CYP1A1 polymorphism plays a role in the development of gynecological malignancy in the Japanese population, we assessed the association of CYP1A1 polymorphism in Japanese patients with gynecological malignancy in comparison to that in controls. The odds ratios (ORs) of Ile/Val polymorphism were 1.16 in ovarian cancer patients and 1.70 in endometrial cancer patients. The ORs of MspI polymorphism were 1.33 in ovarian cancer patients and 0.88 in endometrial cancer patients. No significant association was found between these CYP1A1 polymorphisms and gynecological malignancy. Although the frequency of CYP1A1 polymorphism in the Japanese population is higher than that in the Caucasian population, CYP1A1 polymorphism is not related to gynecological malignancies in Japanese population.

Beneficial effect of pretreatment of islets with fibronectin on glucose tolerance after islet transplantation

The scarcity of available islets is an obstacle for clinically successful islet transplantation. One solution might be to increase the efficacy of the limited islets. Isolated islets are exposed to a variety of cellular stressors, and disruption of the cell-matrix connections damages islets. We examined the effect of fibronectin, a major component of the extracellular matrix, on islet viability, mass and function, and also examined whether fibronectin-treated islets improved the results of islet transplantation. Islets cultured with fibronectin for 48 hours maintained higher cell viability (0.146 +/- 0.010 vs. 0.173 +/- 0.007 by MTT assay), and also had a greater insulin and DNA content (86.8 +/- 3.6 vs. 72.8 +/- 3.2 ng/islet and 35.2 +/- 1.4 vs. 30.0 +/- 1.5 ng/islet, respectively) than islets cultured without fibronectin (control). Absolute values of insulin secretion were higher in fibronectin-treated islets than in controls; however, the ratio of stimulated insulin secretion to basal secretion was not significantly different (206.9 +/- 23.3 vs. 191.7 +/- 20.2% when the insulin response to 16.7 mmol/l glucose was compared to that of 3.3 mmol/l glucose); the higher insulin secretion was thus mainly due to larger islet cell mass. The rats transplanted with fibronectin-treated islets had lower plasma glucose and higher plasma insulin levels within 2 weeks after transplantation, and had more favorable glucose tolerance 9 weeks after transplantation. These results indicate that cultivation with fibronectin might preserve islet cell viability, mass and insulin secretory function, which could improve glucose tolerance following islet transplantation.

Glutathione S-transferase M1 and T1 polymorphisms and the risk of recurrent pregnancy loss

The aetiology of recurrent pregnancy loss (RPL) remains unclear, but it may be related to a possible genetic predisposition together with involvement of environmental factors. We examined the relation between RPL and polymorphisms in two genes, glutathione S-transferases (GST) M1 and T1, which are involved in the metabolism of a wide range of environmental toxins and carcinogens. A case-control study of 115 cases with RPL and 160 controls was conducted. All cases and controls were women resident in Sapporo, Japan and the surrounding area. They were genotyped for polymorphisms of GSTM1 and GSTT1 using PCR-based methods. We found that 65.2% of the cases with RPL and 45.6% of the controls had the GSTM1 null genotype [odds ratio (OR) = 2.23, 95% confidence interval (CI) = 1.36-3.66]. On the other hand, 47.0% of the cases and 49.4% of the controls had the GSTT1 null genotype (OR = 0.95; 95% CI = 0.58-1.55). The results suggest that women with GSTM1 null polymorphism may therefore have an increased risk of RPL.

Effects of long-term administration of methionine on vascular endothelium in rabbits

BACKGROUND AND AIM

We studied the effects of long-term methionine administration on the vascular endothelium of Japanese white rabbits.

METHODS AND RESULTS

Eleven rabbits were divided into a control group (n = 6) and a methionine-fed group (n = 5), and reared for 22 weeks. Blood samples were collected at baseline and after 22 weeks for the measurement of serum homocysteine and cysteine, serum lipids and serum superoxide dismutase activity. At the end of experiments, the animals were sacrificed, and the thoracic aorta was removed for the measurement of isometric tension and histopathological examination. The blood samples taken from the methionine group in the 22nd week showed slight but significant increases in serum homocysteine and cysteine levels (Hcy: 13.7 +/- 1.4 vs 21.0 +/- 4.9, p < 0.01; Cys: 241.6 +/- 37.8 vs 342.6 +/- 35.0, p < 0.01). In the isometric tension experiments, the methionine group had a significantly decreased (p < 0.01) vasodilatation reaction induced by acetylcholine, an endothelium-dependent vasodilator. The histopathological examination (immunostaining in response to eNOS and tissue factor) showed significant increases in endothelium expression in the methionine group before atherosclerotic changes appeared.

CONCLUSIONS

The above results suggest that vascular endothelial dysfunction played an important role in the atherosclerosis occurring after excess methionine feeding.

Clinical pilot studies on pre-operative hyperthermic tumour ablation for advanced breast carcinoma using an 8 MHz radiofrequency heating device

The multimodality treatment approach for advanced breast cancer provides survival advantages with decreased locoregional and distant recurrences, but these intensive anti-tumour treatments cause severe myelosuppression. Thus, in this study, the usefulness of pre-operative anti-tumour treatment without myelosuppression was investigated. Nine patients with advanced breast carcinoma underwent pre-operative hyperthermic tumour ablation (HTA) using an 8 MHz radiofrequency (RF) heating device (Thermotron RF-8) combined with a grounded needle electrode. The patients had a mean age of 58.3+/-13.9 years and included four patients with stage IIIA, two with stage IIIB and three with stage IV cancer. The target temperature was over 50 degrees C. They tolerated pre-operative HTA therapy well with no early or late complications. The initial mean tumour size was 122.1+/-71.5 cm3 and the post-HTA tumour size was 82.2+/-63.4 cm3; the reduction rate was significant (p = 0.000 293). After the pre-operative HTA, all patients underwent surgery with Level III nodal extirpation. Post-operatively, no locoregional recurrence was observed. Microscopic examination of the primary focus showed complete coagulation necrosis expanding for a diameter of 3.5-5.0 cm. Taken together, the pre-operative HTA was a safe, well-tolerated and effective treatment, achieving tumour reduction as well as complete coagulation necrosis that resulted in a large volume of destruction in breast cancer tissue.

CYP1A1 polymorphism and risk of gynecological malignancy in Japan

The incidence of endometrial cancer and ovarian cancer in Japan has been increasing in recent years. Results of epidemiologic studies suggest that the onset and multiplication of these cancers are associated with estrogen. Estrogens are metabolized by cytochrome P450 1A1 (CYP1A1) and converted into catecholestrogens, which are carcinogens. CYP1A1 has several polymorphisms, the major one being T6235C transition in the non-coding 3′-flanking region (MspI polymorphism), and another being A4889G transition in exon 7 (Ile/Val polymorphism). These polymorphisms can affect the metabolites of estrogens and contribute to the susceptibility to gynecological malignancy. In this study, to determine whether CYP1A1 polymorphism plays a role in the development of gynecological malignancy in the Japanese population, we assessed the association of CYP1A1 polymorphism in Japanese patients with gynecological malignancy in comparison to that in controls. The odds ratios (ORs) of Ile/Val polymorphism were 1.16 in ovarian cancer patients and 1.70 in endometrial cancer patients. The ORs of MspI polymorphism were 1.33 in ovarian cancer patients and 0.88 in endometrial cancer patients. No significant association was found between these CYP1A1 polymorphisms and gynecological malignancy. Although the frequency of CYP1A1 polymorphism in the Japanese population is higher than that in the Caucasian population, CYP1A1 polymorphism is not related to gynecological malignancies in Japanese population.

Eating epilepsy characterized by periodic spasms

Seizures induced by eating are generally considered rare. Eating epilepsy is a kind of reflex epilepsy. We report two patients aged 11 and 16, with seizures provoked by eating. The eating-provoked seizures in both patients were a series of tonic spasms. Both ictal EEGs showed a periodic pattern characterized by diffuse high voltage slow wave. These findings were consistent with periodic spasms described by Gobbi et al. The ECD were widely distributed in both patients, although that of Patient 1 was partially clustered in the right frontal region. This is the first report of patients with periodic spasms induced by eating.

Concentration of 17beta-estradiol using an immunoaffinity porous hollow-fiber membrane

We describe attempts to achieve high throughput of 17beta-estradiol (E2) analysis, including the development of an immunocleanup membrane using polyclonal antibodies and an enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies. An epoxy-group-containing monomer, glycidyl methacrylate (GMA), was graft-polymerized onto a porous hollow-fiber membrane. Subsequently, anti-estrogen (ES) antibody, as a ligand, was coupled with the epoxy group. The ligand density ranged from 3.1 to 5.8 mg/g of the GMA-grafted porous hollow-fiber membrane. A 1.0 microg/L E2 solution was forced to permeate through pores rimmed by the anti-ES-antibody-immobilized polymer chains, at a constant permeation rate. A breakthrough curve, that is, the change in the E2 concentration of the effluent penetrating the outside of the hollow fiber with a change of the effluent volume, was determined. Bound E2 in amounts ranging from 0.42 to 0.80 microg was quantitatively eluted with 3-5 mL of methanol in the permeation mode. The higher permeation rate of the E2 solution resulted in the higher overall binding rate of E2 to the anti-ES-antibody-immobilized porous hollow-fiber membrane because of the negligible diffusional mass-transfer resistance of E2 to the antibody.