Arteriolosclerosis differs from venular collagenosis in relation to cerebrovascular parenchymal damages: an autopsy-based study.

BACKGROUND AND PURPOSE: Cerebrovascular parenchymal damage is prevalent in ageing brains; however, its vascular aetiology has not been fully elucidated. In addition to the underlying role of sclerotic arterioles, the correlation between collagenised venules has not been clarified. Here, we aimed to investigate the associations between microvascular injuries, including arteriolosclerosis and venular collagenosis, and related parenchymal damages in ageing brains, to investigate the underlying correlations. METHODS: We evaluated arteriolosclerosis and venular collagenosis in 7 regions from 27 autopsy cases with no history of stroke or brain tumour. The correlations between the ratio of arteriolosclerosis, venular collagenosis and the severity of cerebrovascular parenchymal damage, including lacunes, microinfarcts, myelin loss, and parenchymal and perivascular haemosiderin deposits, were assessed. RESULTS: Arteriolosclerosis and venular collagenosis became more evident with age. Arteriolosclerosis was associated with lacunes (p=0.004) and brain parenchymal haemosiderin deposits in the superior frontal cortex (p=0.024) but not with leukoaraiosis severity. Venular collagenosis was not associated with the number of lacunes or haemosiderin, while white matter generally became paler with severe venular collagenosis in the periventricular (ß=-0.430, p=0.028) and deep white matter (ß=-0.437, p=0.025). CONCLUSION: Our findings imply an important role for venular lesions in relation to microvessel-related parenchymal damage which is different from that for arteriolosclerosis. Different underlying mechanisms of both cerebral arterioles and venules require further investigation.

Phosphorylation of levan by microwave-assisted synthesis enhanced anticancer ability.

Levan is an exopolysaccharide produced by Bacillus licheniformis (strain FRI MY-55) that shows promising pharmacological activity. Phosphorylation is a chemical modification that can increase the biological and antioxidant properties of levan. In this study, levan was phosphorylated by microwave-assisted synthesis to achieve a degree of substitution of 0.29. The hydroxyl radical scavenging activity of microwave-assisted phosphorylated levan (microwave P) increased significantly (6-fold) over native levan; this activity was only slightly lower than vitamin C. Other free radical scavenging and reducing power tests revealed that Microwave P activity was increased by 30-40%. Microwave P inhibited the proliferation of HCT-116 and A549 cancer cell lines more readily than native levan with an IC50 of 1.03 mg/mL and 1.38 mg/mL for HCT-116 and A549 cells, respectively. Cells treated with native levan and its derivatives remained in the sub-G1 phase according to cell cycle analysis, whereas Microwave P treatment increased the proportion of cells undergoing apoptosis. Furthermore, Microwave P effectively upregulated pro-apoptosis marker Bax and downregulated anti-apoptosis marker Bcl-2, in addition to inducing the expression of caspase-9 and caspase-3. These findings show that levan phosphorylated via microwave-assisted synthesis showed increased antioxidant and antitumor activity over native levan or levan phosphorylated via traditional long-term heating. In particular, Microwave P possesses antiproliferative activity and can induce apoptosis through mitochondrial pathways in cancerous cells.

Change of Peripheral Blood Treg/Thl7 in Cognitive Impairment with Chronic Renal Failure Patients.

BACKGROUND/AIMS: To investigate the changes in peripheral blood Treg/Th17 cell balance and its significance in patients with chronic renal failure (CRF) and cognitive impairment. METHODS: A total of 71 patients with CRF were enrolled as a study group. The patients were divided into a cognitive impairment group and a normal cognitive function group according to the Mini-Mental State Examination (MMSE). Peripheral blood Treg and Th17 cells were analyzed by flow cytometry and their relevant cytokines (IL-17, IL-10 and TGF-ß) and other biochemical indicators, including C-reactive protein (CRP) and IL-6, were determined by ELISA. RESULTS: Thepatients with both CRF and cognitive impairment were older than the cognitive normal groups. Peripheral blood Treg cells by Flow cytometry (the CRF cognitive impairment group 5.57±1.3%, CRF group with normal cognitive function 7.5 ± 0.9% and normal control group 9.7 ± 1.7%,P<0.05) and its related cytokines (IL-10 and TGF-ß) by ELISA detection were lower in the group with cognitive impairment than in the group without cognitive impairment ( IL-10, 7.4±4.2 pg/mL, 13.8±3.9 pg/mL, 18.3±3.2 pg/mL; TGF-ß 335.6±175.3 pg/mL, 512.7 ± 114.6 pg/mL, 953.8±373.4 pg/mL P < 0.05, respectively).However, Th17 cell numbers (the CRF cognitive impairment group 3.3 ± 0.7%, CRF group with normal cognitive function2.2 ± 0.5% and normal control group 1.5 ± 0.3%),and cytokine levels (IL-17, IL-6 and CRP) were higher in the group with cognitive impairment IL-6 (21.3 ± 5.1 pg/mL), IL-17 (18.5 ± 4.2 pg/mL) and CRP (20.3 ± 5.9 mg/L) in the CRF group with cognitive impairment when compared with the CRF group and normal cognitive function (12.2 ± 4.5 pg/mL, 12.1 ± 3.7 pg/mL and 13.5 ± 4.6 mg/L, respectively) or the normal control group (9.2 ± 5.8 pg/mL, 7.4 ± 2.6 pg/mL and 3.2 ± 1.3 mg/L, respectively, P<0.05). The frequencies of Treg in patients with CRF were positively correlated with the MMSE scores ((r = 0.518, P < 0.05), but the Th17 numbers were negatively correlated (r = -0.435, P < 0.05). CONCLUSION: An imbalance of peripheral blood Treg/Th17 cells is associated with cognitive impairment in patients with CRF.

Purification and characterization of polyphenol oxidase from rape flower.

The purification and partial enzymology characteristics of polyphenol oxidase (PPO) from rape flower were studied. After preliminary treatments, the crude enzyme solution was in turn purified with ammonium sulfate, dialysis, and Sephadex G-75 gel chromatography. The optimal conditions and stability of PPO were examined at different pH values and temperatures. Subsequently, PPO was also characterized by substrate (catechol) concentrations, inhibitors, kinetic parameters, and molecular weight. Results showed that the optimal pH for PPO activity was 5.5 in the presence of catechol and that PPO was relatively stable at pH 3.5-5.5. PPO was moderately stable at temperatures from 60 to 70 °C, whereas it was easily denatured at 80-90 °C. Ethylenediaminetetraacetic acid, sodium chloride, and calcium chloride had little inhibitive effects on PPO, whereas citric acid, sodium sulfite, and ascorbic acid had strongly inhibitive effects. The Michaelis-Menten constant (K(m)) and maximal reaction velocity (V(max)) of PPO were 0.767 mol/L and 0.519 Ab/min/mL of the crude PPO solution, respectively. PPO was finally purified to homogeneity with a purification factor of 4.41-fold and a recovery of 12.41%. Its molecular weight was 60.4 kDa, indicating that the PPO is a dimer. The data obtained in this research may help to prevent the enzymatic browning of rape flower during its storage and processing.