Bell-Shaped Electron Transfer Kinetics in Gold Nanoclusters.

Although metal nanoclusters (MNCs) have shown great promise for the further development of photochemical techniques to be applied in diverse areas (e.g., photoelectronic devices, photochemical sensors, photocatalysts, and energy storage and conversion systems), the fundamental problem of their electron transfer behavior still remains unsolved. Herein, a driving force-dependent photoinduced electron transfer process of gold nanoclusters (AuNCs) is clarified for the first time from a rational-designed opposite-charged system. It was found that the electron transfer dynamic of carboxylated chitosan and dithiothreitol-commodified AuNCs (CC/DTT-AuNCs) can be satisfactorily described by the Marcus electron transfer theory. This proved model was applied to estimate the ultrafast charge separation process between CC/DTT-AuNCs and mitoxantrone, which was confirmed by fluorescence quenching and femtosecond transient absorption spectroscopy measurements. We envision that this work will open a new door for understanding the electron transfer behavior of MNCs and facilitate the design of advanced optoelectronic devices.

Suppression of TRPM7 inhibits proliferation, migration, and invasion of malignant human glioma cells.

BACKGROUND: Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor with a dismal prognosis. Despite intensive study on tumor biology, the underlying mechanisms of the unlimited proliferation and progressive local invasion are still poorly understood, and no effective treatment has been developed for GBM patients. AIMS: We determine the role of TRPM7 channels in the growth, migration, and infiltration of malignant glioma cells. METHODS: Using a combination of RT-PCR, Western blot, and patch-clamp techniques, we demonstrated the expression of functional TRPM7 channels of A172 cells, a human glioma cell line, as well as in human glioma tissues. Furthermore, we evaluated the role of TRPM7 in growth, migration, and infiltration of A172 cells with MTT and transwell migration and invasion assays. RESULTS: We showed the expression of functional TRPM7 channels in both A172 cells and human glioma tissues. Suppression of TRPM7 expression with TRPM7-siRNA dramatically reduced the proliferation, migration, and invasion of A172 cells. Pharmacological inhibition of TRPM7 channel with 2-aminoethoxydiphenyl borate (2-APB) showed a similar effect as TRPM7-siRNA. CONCLUSION: We demonstrate that human glioma cells express functional TRPM7 channel and that activation of this channel plays an important role in the proliferation, migration, and invasion of malignant glioma cells. TRPM7 channel may represent a novel and promising target for therapeutic intervention of malignant glioma.

[Clinical effectiveness of INSURE method in the treatment of neonatal respiratory distress syndrome].

OBJECTIVE: To evaluate the clinical effectiveness and safety of intubation-surfactant-extubation (INSURE) method in the treatment of neonatal respiratory distress syndrome (NRDS), and to investigate its possible mechanisms. METHODS: Sixty-four premature infants, who were admitted for NRDS and treated with pulmonary surfactant from March 2010 to March 2012, were enrolled in the study. They were randomly divided into INSURE (n=32) and conventional mechanical ventilation (CMV) groups (n=32). The two groups were compared in terms of respiratory function, ventilation time, duration of oxygen therapy, complications, and prognosis, as well as expression of interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α) and serum ferritin (SF). RESULTS: Oxygenation index in the INSURE group was significantly higher than in the CMV group at 48 hours after treatment (P<0.05). Compared with the CMV group, the INSURE group showed significantly lower incidence of ventilator-associated pneumonia (VAP) and significantly shorter duration of oxygen therapy (P<0.05 for all comparisons). There were no significant differences in ventilation time and the incidence of pneumothorax, intracranial hemorrhage, necrotizing enteroolitis, bronchopulmonary dysplasia, and pneumorrhagia between the two groups (P>0.05). The levels of TNF-α and SF were significantly lower in the INSURE group than in the CMV group at 6, 24, 48, and 72 hours after treatment (P<0.05), while the level of IL-10 was significantly higher in the INSURE group than in the CMV group (P<0.05). CONCLUSIONS: INSURE method can improve the oxygenation function of the lung, decrease the incidence of VAP and shorten the duration of oxygen therapy in neonates with NRDS, which is probably due to the fact that this method can reduce the production of TNF-α and SF and inhibit the decrease of IL-10.

Effectiveness of HBV vaccination in infants and prediction of HBV prevalence trend under new vaccination plan: findings of a large-scale investigation.

BACKGROUND: Hepatitis B virus (HBV) infection remains a severe public health problem. Investigating its prevalence and trends is essential to prevention. METHODS: To evaluate the effectiveness of HBV vaccination under the 1992 Intervention Program for infants and predicted HBV prevalence trends under the 2011 Program for all ages. We conducted a community-based investigation of 761,544 residents of 12 counties in Zhejiang Province selected according to their location, population density, and economic development. The HBV prevalence trends were predicted by a time-shifting approach. HBV surface antigen (HBsAg) and alanine amino transferase (ALT) were determined. RESULTS: Of the 761,544 persons screened for HBsAg, 54,132 were positive (adjusted carrier rate 6.13%); 9,455 had both elevated ALT and a positive HBsAg test (standardized rate 1.18%). The standardized HBsAg carrier rate for persons aged ≤20 years was 1.51%. Key factors influencing HBV infection were sex, age, family history, drinking, smoking, employment as a migrant worker, and occupation. With the vaccination program implemented in 2011, we predict that by 2020, the HBsAg carrier rate will be 5.27% and that for individuals aged ≤34 years will reach the 2% upper limit of low prevalence according to the WHO criteria, with a standardized rate of 1.86%. CONCLUSIONS: The national HBV vaccination program for infants implemented in 1992 has greatly reduced the prevalence of HBV infection. The 2011 program is likely to reduce HBV infection in Zhejiang Province to a low moderate prevalence, and perinatal transmission is expected to be controlled by 2020.

SB-431542 inhibition of scar formation after filtration surgery and its potential mechanism.

PURPOSE: To explore the inhibitive effect of SB-431542 (an ALK5 inhibitor) on scar formation after glaucoma surgery and to identify the potential pharmacologic target(s). METHODS: Twenty-four New Zealand rabbits underwent filtration surgery on the right eye and were divided into a control group and three experimental groups (n=6). Human Tenon's fibroblast monolayer was scraped to generate a single gap, and then the control medium with SB-431542 only or containing 10 microg/L TGF-beta1 and SB-431542 (1-20 microM) was added. The cells were pretreated with SB-431542 or in control medium for 30 minutes before induction with 10 microg/L TGF-beta1 or 1 microg/L TGF-beta2. The expression of alpha-SM-actin, CTGF, and Col I, as well as changes in the Smad, ERK, P38, and AKT signaling pathways were detected. RESULTS: In comparison with the control rabbits, the IOPs in the experimental groups remained at lower levels until day 25 (P<0.05) after the surgery. Histologic profiles showed that there was only a mild deposition of collagen in the subconjunctival space in the experimental groups. The cell growth and migration were inhibited effectively by SB-431542, regardless of whether TGF-beta was present in the culture system. SB-431542 abrogated TGF-beta-induced upregulation of alpha-SM-actin, CTGF, and Col I. It effectively inhibited the phosphorylation of Smad2 stimulated by TGF-beta but not that of the components of the MAPK pathways. CONCLUSIONS: SB-431542 inhibits scar formation after glaucoma filtration surgery. The mechanism may be that SB-431542 interferes in the phosphorylation of Smad2, thus abrogating TGF-beta-induced fibroblast transdifferentiation and then decreasing Col I synthesis.

Study of clinical features of amyloid angiopathy hemorrhage and hypertensive intracerebral hemorrhage.

OBJECTIVE: The purpose of this study was to differentiate between cerebral amyloid angiopathy (CAA) and hypertension (HTN) based on hemorrhage pattern interpretation. METHODS: From June 1994 to Oct., 2000, 83 patients admitted to our service with acute intracerebral hemorrhage (ICH) were investigated retrospectively; 41 patients with histologically proven diagnosis of cerebral amyloid angiography and 42 patients with clear history of hypertension were investigated. RESULTS: Patients with a CAA-related ICH were significantly older than patients with a HTN-related ICH (74.0 years vs 66.5 years, P < 0.05). There was a significantly higher number of hematomas > or = 30 ml in CAA (85.3%) when compared with HTN (59.5%). No basal ganglional hemorrhage was seen in CAA, but in 40.5% in HTN. In CAA-related ICH, subarachnoid hemorrhage (SAH) was seen in 26 patients (63.4%) compared to only 11 patients (26.2%) in HTN-related ICH. Intraventricular hemorrhage was seen in 24.4% in CAA, and in 26.2% in HTN. Typical features of CAA-related ICH included lobar distribution affecting mainly the lobar superficial areas, lobulated appearance, rupture into the subarachnoid space, and secondary IVH from the lobar hemorrhage. More specifically, multiplicity of hemorrhage, bilaterality, and repeated episodes also strongly suggest the diagnosis of CAA. Multiple hemorrhages, defined as 2 or more separate hematomas in multiple lobes, accounted for 17.1% in CAA-related ICH. CONCLUSION: There are certain features in CAA on CT and MRI and in clinical settings. To some extent, these features may contribute to distinguishing CAA from HTN related ICH.