Combined NgR vaccination and neural stem cell transplantation promote functional recovery after spinal cord injury in adult rats.

AIMS: after spinal cord injury (SCI), there are many adverse factors at the lesion site such as glial scar, myelin-derived inhibitors, cell loss and deficiency of neurotrophins that impair axonal regeneration. Therefore, combination therapeutic strategies might be more effective than a single strategy for promoting functional recovery after SCI. In the present study, we investigated whether a Nogo66 receptor (NgR) vaccine, combined with neural stem cell (NSC) transplantation, could promote better functional recovery than when NgR vaccine or NSCs were used alone. METHODS: adult rats were immunized with NgR vaccine at 1 week after a contusive SCI at the thoracic level, and the NSCs, obtained from green fluorescent protein transgenic rats, were transplanted into the injury site at 8 weeks post injury. The functional recovery of the animals under various treatments was evaluated by three independent behavioural tests, that is, Basso, Beattie and Bresnahan locomotor rating scale, footprint analysis and grid walking. RESULTS: the combined therapy with NgR vaccination and NSC transplantation protected more ventral horn motor neurones in the injured spinal cord and greater functional recovery than when they were used alone. Furthermore, NgR vaccination promoted migration of engrafted NSCs along the rostral-caudal axis of the injured spinal cords, and induced their differentiation into neurones and oligodendrocytes in vivo. CONCLUSIONS: the combination therapy of NgR vaccine and NSC transplantation exhibited significant advantages over any single therapy alone in this study. It may represent a potential new therapy for SCI.

Postoperative radiotherapy option based on mediastinal lymph node reclassification for patients with pN2 non-small-cell lung cancer.

Background: In this research, we used the mediastinal lymph node reclassification proposed by the International Association for the Study of Lung Cancer (iaslc) to screen for patients with pathologic N2 (pN2) non-small-cell lung cancer (nsclc) who might benefit from postoperative radiotherapy (port). Methods: The study enrolled 440 patients with pN2 nsclc who received complete surgical resection and allocated them to one of three groups: N2a1 (single-station skip mediastinal lymph node metastasis), N2a2 (single-station non-skip mediastinal lymph node metastasis), and N2b (multi-station mediastinal lymph node metastasis). Rates of local recurrence at first recurrence in patients receiving and not receiving port were compared using the chi-square test. Overall (os) and disease-free survival (dfs) were then compared using Kaplan-Meier survival analysis with log-rank test. In addition, the factors potentially influencing os and dfs were analyzed using univariate and multivariate Cox regression. Results: The rate of local recurrence for the N2a2 and N2b groups was significantly lower in patients receiving port (p = 0.044 and p = 0.043 respectively). The log-rank test revealed that, for the N2a1 group, differences in os and dfs were not statistically significant between the patients who did and did not receive port (p = 0.304 and p = 0.197 respectively). For the N2a2 group, os and dfs were markedly superior in patients who received port compared with those who did not (p = 0.001 and p = 0.014 respectively). For the N2b group, os was evidently better in patients who received port compared with those who did not (p = 0.025), but no statistically significant difference in dfs was observed (p = 0.134). Multivariate regression analysis revealed that, in the N2a1 group, port was significantly associated with poor os [hazard ratio (hr): 2.618; 95% confidence interval (ci): 1.185 to 5.785; p = 0.017]; in the N2a2 group, port was associated with improved os (hr: 0.481; 95% ci: 0.314 to 0.736; p = 0.001) and dfs (hr: 0.685; 95% ci: 0.479 to 0.980; p = 0.039). Conclusions: For patients with pN2 nsclc who receive complete resection, port might be beneficial only for patients with single-station non-skip metastasis (N2a2). Patients with single-station skip metastasis (N2a1) and multi-station metastasis (N2b) might not currently benefit from port.

Retrospective investigation of hospitalised patients with atrial fibrillation in mainland China.

OBJECTIVE: To evaluate the epidemiology and status of atrial fibrillation in China. METHODS: Retrospective analysis of hospital records of patients with a primary diagnosis of atrial fibrillation, discharged between January 1999 and December 2001. RESULTS: Data were analysed from 9297 patients (mean age 65.5 years) from 41 hospitals in mainland China. During the period studied, atrial fibrillation admissions (mean 7.9%) increased as a proportion of cardiovascular admissions. The distribution of atrial fibrillation increased with age. Causes and associated conditions were advanced age (58.1%), hypertension (40.3%), coronary heart disease (34.8%), heart failure (33.1%), rheumatic valvular disease (23.9%), idiopathic atrial fibrillation (7.4%), cardiomyopathy (5.4%) and diabetes (4.1%). Permanent atrial fibrillation accounted for almost half of the patients (49.5%), and paroxysmal and persistent atrial fibrillation the remainder (33.7% and 16.7%, respectively). Paroxysmal atrial fibrillation was treated mainly by rhythm control (56.4%). In 82.8% of patients with chronic atrial fibrillation, a rate-control strategy was used. The prevalence of stroke was 17.5%. In non-valvular atrial fibrillation, risk factors associated with stroke included advanced age, history of hypertension, coronary heart disease and type of atrial fibrillation. A total of 64.5% of patients received antithrombotic therapy, predominantly with antiplatelet agents. Patients managed with antiplatelet or anticoagulant drugs had a significantly lower stroke rate than those receiving neither treatment, but there was no significant difference between antiplatelet and anticoagulant agents. CONCLUSION: Most of the atrial fibrillation-related epidemiological factors in this population were similar to those reported in other countries. Antiplatelet and anticoagulant treatment both reduced stroke rate significantly.

MIF4G domain containing protein regulates cell cycle and hepatic carcinogenesis by antagonizing CDK2-dependent p27 stability.

The CDK inhibitor p27(kip1) plays crucial roles in cell cycle regulation and cancer progression. Through yeast two-hybrid screening, we identified MIF4G domain containing protein (MIF4GD) as a novel binding partner for p27. The association of MIF4GD and p27 was verified using immunoprecipitation and glutathione S-transferase (GST) pull-down assays. Interaction with MIF4GD led to the stabilization of p27 both in the nucleus and in the cytoplasm in hepatocellular carcinoma (HCC) cells as a result of suppressed phosphorylation of p27 by CDK2 at threonine187. Serum stimulation decreased the levels of MIF4GD and p27 simultaneously. In addition, MIF4GD overexpression resulted in increased p27 levels and reduced cell proliferation, while knockdown of MIF4GD promoted cell cycle progression with decreased p27 levels in cells. Furthermore, overexpression of MIF4GD reduced colony formation and inhibited xenograft tumor growth in nude mice. Finally, we found that both MIF4GD and p27 were expressed at low levels in HCC tissues compared to non-cancerous tissues, and that low expression levels of MIF4GD and p27 were associated with significantly worse prognosis in HCC patients. Our results suggest that MIF4GD is a potential regulator of p27-dependent cell proliferation in HCC. These findings provide a rational framework for the development of potential HCC therapy by targeting the MIF4GD-p27 interaction.

Microscopical and physical characterization of microwave and microwave-hydrothermal synthesis products.

Application of microwave energy for materials processing is emerging as an innovative technology with many advantages over the conventional processing, and the rapid progress in this field suggests that microwave material processing (e.g., microwave and microwave-hydrothermal process) will play an outstanding role in the broad field of nanoscience and nanotechnology. This review article gives an up-to-date overview of the current microscopical and physical characterization of the products synthesized by microwave and microwave-hydrothermal process, particularly for oxide nanomaterials because they are indispensable for nanotechnological innovations due to their combinations of infinite variety of structural motifs and properties with manifold morphological features. Basic principles, advantages, and limitations of microwave and microwave-hydrothermal processes are first introduced, and then their recent applications in the synthesis of different classes of functional materials especially for oxide nanomaterials are critically reviewed. Next, the recent progress on the structural and physical characterizations is summarized and discussed. Finally, prospects for future researches within this field are elaborated.

Cloning, expression, and biochemical characterization of hexahistidine-tagged terminase proteins.

The terminase enzyme from bacteriophage lambda is composed of two viral proteins (gpA, 73.2 kDa; gpNu1, 20.4 kDa) and is responsible for packaging viral DNA into the confines of an empty procapsid. We are interested in the genetic, biochemical, and biophysical properties of DNA packaging in phage lambda and, in particular, the nucleoprotein complexes involved in these processes. These studies require the routine purification of large quantities of wild-type and mutant proteins in order to probe the molecular mechanism of DNA packaging. Toward this end, we have constructed a hexahistidine (hexa-His)-tagged terminase holoenzyme as well as hexa-His-tagged gpNu1 and gpA subunits. We present a simple, one-step purification scheme for the purification of large quantities of the holoenzyme and the individual subunits directly from the crude cell lysate. Importantly, we have developed a method to purify the highly insoluble gpNu1 subunit from inclusion bodies in a single step. Hexa-His terminase holoenzyme is functional in vivo and possesses steady-state and single-turnover ATPase activity that is indistinguishable from wild-type enzyme. The nuclease activity of the modified holoenzyme is near wild type, but the reaction exhibits a greater dependence on Escherichia coli integration host factor, a result that is mirrored in vivo. These results suggest that the hexa-His-tagged holoenzyme possesses a mild DNA-binding defect that is masked, at least in part, by integration host factor. The mild defect in hexa-His terminase holoenzyme is more significant in the isolated gpA-hexa-His subunit that does not appear to bind DNA. Moreover, whereas the hexa-His-tagged gpNu1 subunit may be reconstituted into a holoenzyme complex with wild-type catalytic activities, gpA-hexa-His is impaired in its interactions with the gpNu1 subunit of the enzyme. The results reported here underscore that a complete biochemical characterization of the effects of purification tags on enzyme function must be performed prior to their use in mechanistic studies.

[Plasma Lp (a) levels and correlation of Lp (a) with fibrinolysis activation in chronic renal failure].

Plasma Lp (a) concentration and activation of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1(PAI-1) were determined in 50 patients with chronic renal failure (CRF) and in 50 healthy subjects. The results demonstrated that plasma concentration of Lp(a) was significantly higher and plasma t-PA activation was significantly lower in CRF patients than in healthy subjects. With multivariate analyses, plasma Lp(a) concentration was positively correlated with the total amount of 24 h uric protein, plasma BUN and uric protein concentration. Moreover, a negative significant correlation between plasma Lp(a) levels and t-PA activation was observed. Plasma Lp(a) levels did not show a correlation to PAI-1 activation. It is indicated that renal function may contribute to moderate plasma Lp(a) concentration and elevated Lp(a) levels may be related with fibrinolytic impairment.

Mutations that extend the specificity of the endonuclease activity of lambda terminase.

Terminase, an enzyme encoded by the Nu1 and A genes of bacteriophage lambda, is crucial for packaging concatemeric DNA into virions. cosN, a 22-bp segment, is the site on the virus chromosome where terminase introduces staggered nicks to cut the concatemer to generate unit-length virion chromosomes. Although cosN is rotationally symmetric, mutations in cosN have asymmetric effects. The cosN G2C mutation (a G-to-C change at position 2) in the left half of cosN reduces the phage yield 10-fold, whereas the symmetric mutation cosN C11G, in the right half of cosN, does not affect the burst size. The reduction in phage yield caused by cosN G2C is correlated with a defect in cos cleavage. Three suppressors of the cosN G2C mutation, A-E515G, A-N509K, and A-R504C, have been isolated that restore the yield of lambda cosN G2C to the wild-type level. The suppressors are missense mutations that alter amino acids located near an ATPase domain of gpA. lambda A-E515G, A-N509K, and A-R504C phages, which are cosN+, also had wild-type burst sizes. In vitro cos cleavage experiments on cosN G2C C11G DNA showed that the rate of cleavage for A-E515G terminase is three- to fourfold higher than for wild-type terminase. The A-E515G mutation changes residue 515 of gpA from glutamic acid to glycine. Uncharged polar and hydrophobic residues at position 515 suppressed the growth defect of lambda cosN G2C C11G. In contrast, basic (K, R) and acidic (E, D) residues at position 515 failed to suppress the growth defect of lambda cosN G2C C11G. In a lambda cosN+ background, all amino acids tested at position 515 were functional. These results suggest that A-E515G plays an indirect role in extending the specificity of the endonuclease activity of lambda terminase.