Tuning surface grafting density of CeO2 nanocrystals with near- and supercritical solvent characteristics

In this work, the solvent effect on the synthesis of CeO₂ nanocrystals prepared in near- and supercritical alcohols is discussed.

A 13-week subchronic toxicity study of dietary administered saponin-rich and isoflavones-containing soybean extract in F344 rats

A subchronic toxicity study of soybean extract was performed in F344 rats with dietary administration at concentrations of 0%, 1.25%, 2.5% and 5% for 13 weeks. No mortality or abnormal clinical signs in any group were observed. Body weight gains were decreased with a tendency for reduction of feed intake in the 1.25% and above female and 5% male groups. In males, absolute and relative liver weights were increased in the 1.25% and above groups. In females relative kidney weights were increased in the 1.25% and above groups. Other significant changes such as decreased RBC and hematocrit and increased urea nitrogen were detected in the 2.5% and/or 5% groups. On histopathological observation, atrophy of the ventral prostate was observed in all animals in the 5% male group. Mucification and atrophy of the vaginal epithelium and increased atretic follicles in ovaries were noted in 2.5% and 5% female rats. Based on the above findings the lowest-observed-adverse-effect level for male and female rats was estimated to be 1.25% (707.2 and 751.8 mg/kg b.w./day, respectively).

Evaluation of toxicity of green tea catechins with 90-day dietary administration to F344 rats

Green tea catechins (GTC), polyphenols extracted from the stalks and leaves of Camellia sinensis, are found in the different types of tea beverages and as antioxidant additives to many foods, snacks, fats and fatty oils. As a part of their safety assessment, subchronic toxicity was investigated in male and female F344 rats with dietary administration at concentrations of 0 (control), 0.3%, 1.25% and 5.0% for 90 days. The average daily intakes of GTC in each group were 180, 764 and 3525mg/kg body weight/day, respectively for males, and 189, 820 and 3542mg/kg body weight/day, respectively for females. No mortality or obvious clinical signs were observed throughout the experimental period but body weights were reduced from week 1 to the end of the experiment in 5.0% males. In serum biochemistry, alanine transaminase and alkaline phosphatase in 5.0% males and females and aspartate transaminase in 5.0% females were increased, together with the relative liver weights in both sexes receiving 5.0%. Although decreases were evident for total cholesterol in 0.3-5.0% males and triglycerides in 1.25% and 5.0% males and 5.0% females, these changes were not considered to be adverse. Hematology and histopathological observation revealed no GTC-related toxicological changes. Based on above findings, the no observed adverse effect level (NOAEL) of GTC was estimated to be 1.25% (764mg/kg body weight/day for males and 820mg/kg body weight/day for females).

Chemokine receptor antagonist peptide, viral MIP-II, protects the brain against focal cerebral ischemia in mice

The authors previously reported that mRNA for macrophage inflammatory protein-1alpha (MIP-1 alpha), a member of the CC chemokines, was expressed in glial cells after focal cerebral ischemia in rats. However, the function of chemokines in the ischemic brain remains unclear. Recently, viral macrophage inflammatory protein-II (vMIP-II), a chemokine analogue encoded by human herpesvirus-8 DNA, has been demonstrated to have antagonistic activity at several chemokine receptors. In the present study, the effects of vMIP-II and MIP-1alpha on ischemic brain injury were examined in mice to elucidate the roles of chemokines endogenously produced in the ischemic brain. Intracerebroventricular injection of vMIP-II (0.01-1 microg) reduced infarct volume in a dose-dependent manner when examined 48 hours after 1-hour middle cerebral artery occlusion followed by reperfusion. However, 1 microg MIP-1alpha increased infarct volume in the cortical region. These results supported the possibility that chemokines endogenously produced in the brain are involved in ischemic injury, and that chemokine receptors are potential targets for therapeutic intervention of stroke.

Intravenous administration of MEK inhibitor U0126 affords brain protection against forebrain ischemia and focal cerebral ischemia

Brain subjected to acute ischemic attack caused by an arterial blockage needs immediate arterial recanalization. However, restoration of cerebral blood flow can cause tissue injury, which is termed reperfusion injury. It is important to inhibit reperfusion injury to achieve greater brain protection. Because oxidative stress has been shown to activate mitogen-activated protein kinases (MAPKs), and because oxidative stress contributes to reperfusion injury, MAPK may be a potential target to inhibit reperfusion injury after brain ischemia. Here, we demonstrate that reperfusion after forebrain ischemia dramatically increases phosphorylation level of extracellular signal-regulated kinase 2 (ERK2) in the gerbil hippocampus. In addition, i.v. administration of U0126 (100-200 mg/kg), a specific inhibitor of MEK (MAPK/ERK kinase), protects the hippocampus against forebrain ischemia. Moreover, treatment with U0126 at 3 h after ischemia significantly reduces infarct volume after transient (3 h) focal cerebral ischemia in mice. This protection is accompanied by reduced phosphorylation level of ERK2, substrates for MEK, in the damaged brain areas. Furthermore, U0126 protects mouse primary cultured cortical neurons against oxygen deprivation for 9 h as well as nitric oxide toxicity. These results provide further evidence for the role of MEK/ERK activation in brain injury resulting from ischemia/reperfusion, and indicate that MEK inhibition may increase the resistance of tissue to ischemic injury.

Ebselen reduces cytochrome c release from mitochondria and subsequent DNA fragmentation after transient focal cerebral ischemia in mice

BACKGROUND AND PURPOSE

The seleno-organic compound ebselen has both antioxidant and anti-inflammatory properties. Although ebselen has been shown to protect the brain against stroke, it is unclear how ebselen provides neuroprotection. In the present study the authors examined whether ebselen inhibits neuronal apoptosis resulting from transient focal cerebral ischemia in mice. The cytochrome c release and DNA fragmentation, both of which are biochemical markers of apoptosis, were compared between vehicle- and ebselen-treated mice.

METHODS

Cerebral ischemia was induced by transient middle cerebral artery occlusion for 30 minutes in ICR mice under halothane anesthesia. Ebselen (10 mg/kg) was given orally twice, 30 minutes before ischemia and 12 hours after reperfusion. By Western blot analysis, we examined release of mitochondrial cytochrome c. To evaluate brain damage, the brain sections were treated for terminal deoxynucleotidyl transferase-mediated DNA nick-end labeling (TUNEL) and Nissl staining. Prolonged neuroprotective efficacy of ebselen was determined by counting neuronal nuclei (NeuN) immunopositive cells at 21 days after ischemia.

RESULTS

- Cytochrome c release was detected in the ischemic hemisphere at 3 to 24 hours after ischemia. Ebselen treatment diminished the cytochrome c release at 12 and 24 hours. In addition, ebselen decreased both DNA fragmentation determined by TUNEL and brain damage volume at 3 days after ischemia. Furthermore, ebselen increased the number of NeuN immunopositive cells at 21 days after ischemia.

CONCLUSIONS

These results indicate that ebselen attenuates ischemic neuronal apoptosis by inhibiting cytochrome c release. Ebselen may be a potential compound in stroke therapy.

Vomeronasal epithelial cells of human fetuses contain immunoreactivity for G proteins, Go(alpha) and Gi(alpha 2)

Two G protein subfamilies, Go(alpha) and Gi(alpha 2), were identified and localized immunohistochemically in the vomeronasal organ (VNO) of 5-month-old human fetuses. Immunoreactivity for Go(alpha) and Gi(alpha 2) was present in a subset of vomeronasal epithelial cells. Prominent immunoreactivity was observed in apical processes and their apical terminals facing onto the vomeronasal lumen. Nerve fibers associated with the VNO exhibited intense immunoreactivity for Go(alpha) and weak immunoreactivity for Gi(alpha 2). Since Go(alpha) and Gi(alpha 2) are characteristically expressed and coupled with putative pheromone receptors in rodent vomeronasal receptor neurons, the present results suggest the possibility that vomeronasal epithelial cells containing Go(alpha) and Gi(alpha 2) in human fetuses are chemosensory neurons.

Chromosomal instability detected by fluorescence in situ hybridization in Japanese breast cancer patients

The relationship between chromosomal instability (CIN) and prognostic factors was investigated in 31 breast cancers and 5 benign breast lesions (three fibroadenomas and two papillomas). Using fluorescence in situ hybridization (FISH) with chromosome-specific DNA probes of chromosomes 1, 2, 6, 7, 10, 11, 17 and 18, CIN for each case was determined. CIN varied from 8.1% to 59.3% among the breast cancer patients tested, and was significantly higher than that observed in the benign breast lesions (p<0.01). Moreover, CIN showed a significant correlation with lymph node metastases (p<0.05) and estrogen receptor negativity (p<0.01). These findings suggest that CIN might be useful in the prediction of the biological aggressiveness of breast cancers.

Clinicopathologic analysis of breast carcinoma with chromosomal aneusomy detected by fluorescence in situ hybridization

BACKGROUND

The clinicopathologic characteristics of breast carcinoma with chromosomal aneusomy detected by fluorescence in situ hybridization (FISH) have yet to be clarified.

METHODS

Fine-needle aspiration biopsy (FNAB) samples were obtained from 113 breast tumors and were subjected to FISH analysis using centromeric probes for chromosomes 1, 11, and 17 to study a numerical aberration of these chromosomes and its correlation with various clinicopathologic features of breast tumors.

RESULTS

Polysomy was observed in 77.0%, 50.5%, and 37.2% of breast carcinoma samples for chromosomes 1, 11, and 17, respectively, and monosomy was observed in 1.8%, 8.8%, and 22.1% for chromosomes 1, 11, and 17, respectively. High histologic grade showed a significant correlation (P < 0.05) with polysomy of chromosome 11. Lymph node metastasis showed a significant correlation (P < 0.05) with polysomy of all three chromosomes, and positivity of lymph node metastasis increased as the number of polysomic chromosomes increased. In addition, estrogen receptor negativity was correlated significantly (P < 0.05) with monosomy of chromosome 17, and progesterone receptor negativity was correlated significantly (P < 0.05) with polysomy of chromosomes 11 and 17.

CONCLUSIONS

Aneusomy of chromosome 1, 11, or 17 detected by FISH is correlated significantly with various clinicopathologic features of breast carcinoma. Because FISH analysis of chromosomal aneusomy can be done using FNAB samples, this technique seems to have the potential to be used for a better, preoperative definition of the biologic characteristics of breast tumors.

Detection of chromosomal aneusomy by fluorescence in situ hybridization in fine-needle aspirates from breast tumors: application to the preoperative diagnosis of breast carcinoma

BACKGROUND

The authors studied the clinical usefulness of fluorescence in situ hybridization (FISH) analysis of a numerical aberration of chromosomes (aneusomy) using fine-needle aspiration (FNA) samples from patients with breast tumors in the preoperative diagnosis of breast carcinoma.

METHODS

FNA samples were obtained from 176 breast tumors and were subjected to conventional cytology and FISH analysis using the centromere probes for chromosomes 1, 11, and 17. Patients with FNA samples that showed aneusomy in at least one of the three chromosomes were diagnosed as positive.

RESULTS

Histologic examination revealed 157 malignancies and 19 benign results (10 fibroadenomas, 6 intraductal papillomas, 1 intracystic papilloma, and 2 ADH). The sensitivity, specificity, and diagnostic accuracy were 85.4%, 94.7%, and 86.4%, respectively, for cytology and 90.4%, 100%, and 91.5%, respectively, for FISH. Of 15 breast malignancies that were diagnosed with indeterminate cytology, 13 were diagnosed as positive with FISH analysis (sensitivity, 86.7%).

CONCLUSIONS

The results demonstrate that the use of FISH in the diagnosis of FNA samples has a diagnostic accuracy comparable to conventional cytology and is useful in making a definitive diagnosis of malignancy (100% specificity) in patients with indeterminate cytologic results, suggesting that FISH diagnosis can be a good adjunct to conventional cytology.

Deletion polymorphism of angiotensin-converting enzyme gene is associated with postprandial hyperglycaemia in individuals undergoing general check-up

1. Deletion polymorphism, DD, of the angiotensin-converting enzyme (ACE) gene is reported to be related to cardiovascular disease, which is frequently based on insulin resistance. 2. To clarify the relationship between the ACE genotype DD and plasma glucose increases after an oral glucose load, we performed 75 g oral glucose tolerance test (OGTT) in 301 nondiabetic men (age range 30-60 years) undergoing general check-up. 3. Insertion/deletion (I/D) polymorphism of the ACE gene was explored using a polymerase chain reaction. The frequency of the II, ID and DD genotypes was 0.43, 0.43 and 0.14, respectively. 4. There were no differences in baseline clinical characteristics between subjects with each ACE genotype. 5. The mean (+/- SEM) plasma glucose level at 60 min of the OGTT was significantly higher in subjects with the DD genotype (170.8 +/- 6.9 mg/dL) than in subjects with either the II or ID genotype (mean value for two groups 156.6 +/- 2.7 mg/dL; P < 0.05). Moreover, the mean percentage change of plasma glucose after 60 min of the OGTT, a marker of plasma glucose increase, was significantly higher in individuals with the DD genotype than in individuals with either the II or ID genotypes. 6. In contrast, the mean fasting plasma glucose level, the plasma glucose level at 120 min, the glucose response area and the fasting insulin level were not different between individuals with the DD genotype and individuals with other genotypes. 7. In conclusion, subjects with the DD genotype showed transiently higher levels of plasma glucose after an oral glucose load than subjects with other genotypes. Further studies are required to determine whether the association between ACE genotype and postprandial hyperglycaemia influences the incidence of cardiovascular disease and diabetes mellitus.

Localization of calcitonin receptor mRNA in the mouse brain: coexistence with serotonin transporter mRNA

To elucidate the sites of and mechanisms of analgesic effect of centrally injected calcitonin, we examined expression of calcitonin receptor mRNA in the mouse brain by in situ hybridization techniques. Calcitonin receptor mRNA was expressed in various brain regions, including the preoptic area, dorsomedial hypothalamic nucleus, lateral hypothalamic area, periaqueductal gray, dorsal raphe nucleus, locus coeruleus, lateral parabrachial nucleus, gigantocellular reticular nucleus alpha part, lateral paragigantocellular nucleus, raphe magnus nucleus and solitary tract nucleus, which are known to play important roles in pain modulation. In addition, a double in situ hybridization technique demonstrated the intense expression of calcitonin receptor mRNA on serotonergic neurons in some raphe nuclei and the lateral paragigantocellular nucleus, suggesting the involvement of central serotonergic pathways in analgesic effect of calcitonin.

Gene polymorphism of the renin-angiotensin system associates with risk for lacunar infarction. The Ohasama study

The polymorphism of the angiotensin-converting enzyme gene is considered to be associated with increased risk for stroke, but there is a diversity in the results obtained. The genetic involvement of the renin-angiotensin system in stroke also remains unclear. To predict the genetic risk of lacunar infarction, we conducted an association study in an Ohasama population, which is the cohort in a rural region of northern Japan. A total of 134 subjects without major neurological, cardiovascular, or metabolic disorders were recruited. Using brain magnetic resonance imaging, the number of lacunae in each of four brain regions were calculated, and periventricular hyperintensity was classified into five grades. We used the following four candidate gene polymorphisms: angiotensin converting enzyme (ACE)/Insertion(I)-Deletion(D), angiotensinogen (AGT)/M235T, angiotensin II type 1 receptor (AT1)/ A1166C, type 2 receptor (AT2)/C3123A, to examine the association between polymorphisms and the severity of lacunar infarction. AGT/M235T was significantly associated with the number of lacunae in the brain stem, the basal ganglia (P < .05), and whole brain (P < .005) regions. The AT1 polymorphism was also significantly associated with the number of lacunae in the basal ganglia and whole brain regions (P < .05), and with periventricular hyperintensity grade (P < .005) in the younger population. However, ACE and AT2 polymorphisms failed to show an association with either the number of lacunae or the PVH grade. We concluded that AGT and AT1 polymorphisms are independent genetic risk factors for lacunar infarction.