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61.
J S McCasland K L Bernardo K L Probst T A Woolsey 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(5):1832-1836
The processes underlying development, refinement, and retention of the intracortical connections critical for the function of the mammalian brain are unknown. Horseradish peroxidase-labeled fibers in mouse somatosensory barrel cortex, which is patterned like the whiskers on the contralateral face from which it receives inputs, were evaluated by automated image analysis. The sensory nerve to the whiskers was sectioned on postnatal day 7, after the whisker map is set. The deprived barrel cortices, examined in adults, showed drastically diminished intracortical projections relative to normal controls, although the map of the whiskers in the cortex was unchanged. This demonstrates anatomically that the normal pattern of intracortical connections, like the normal sensory map, is dependent upon the sensory periphery four synapses away. 相似文献
62.
Corticosteroids have the ability to suppress the production of growth factors and cytokines and are thus implicated in the negative regulation of hematopoiesis. We have shown that the corticosteroids, prednisolone and dexamethasone, were able to effectively protect progenitor cells in four strains of mice against cell-cycle-specific antimetabolic chemotherapy agents. The highest levels of protection against 5-fluorouracil (FU; 200 mg/kg) were achieved when two or three intraperitoneal injections of dexamethasone were administered between - 7 and +3 hours at a dose of 7.5 mg/kg/injection (optimal dose) or by continuous infusion between -4 and +20 hours. This protective effect is manifested as an increase in the number of high proliferative potential colony-forming cells that survive in the bone marrow 3 days after treatment with FU from between 0.5% and 11% to between 10% and 34% of normal. The bone marrow progenitors and blood cell numbers return to normal from 3 to 5 days and 1 to 2 days earlier, respectively. Less dexamethasone than prednisolone is required to give an equivalent protective effect, which is consistent with their anti-inflammatory potency. These findings are further evidence of the negative regulatory role played by corticosteroids, and indicate that the treatment schedules of corticosteroids during cancer therapy need to be reexamined to obtain the maximum benefit from their use. 相似文献
63.
Mário Sérgio Lima de Lavor Nancy Scardua Binda Fabíola Bono Fukushima Fátima Maria Caetano Caldeira Juliana Figueira da Silva Carla Maria Osório Silva Karen Maciel de Oliveira Bernardo de Caro Martins Bruno Benetti Junta Torres Isabel Rodrigues Rosado Renato Santiago Gomez Marcus Vinícius Gomez Eliane Gon?alves de Melo 《International journal of clinical and experimental pathology》2015,8(9):9941-9949
This work aimed at determining the ideal ischemia time in an in vitro ischemia-reperfusion model of spinal cord injury. Rat spinal cord slices were prepared and then exposed or not to oxygen deprivation and low glucose (ODLG) for 30, 45, 60, 75 and 90 minutes. Cell viability was assessed by triphenyltetrazolium (TTC), lactate dehydrogenase (LDH) release, and fluorochrome dyes specific for cell dead (ethidium homodimer) using the apotome system. Glutamate release was enzymatically measured by a fluorescent method. Gene expression of apoptotic factors was assessed by real time RT-PCR. Whereas spinal cord slices exposed to ODLG exhibited mild increase in fluorescence for 30 minutes after the insult, the 45, 60, 75 and 90 minutes caused a 2-fold increase. ODLG exposure for 45, 60, 75 or 90 minutes, glutamate and LDH release were significantly elevated. nNOS mRNA expression was overexpressed for 45 minutes and moderately increased for 60 minutes in ODLG groups. Bax/bcl-xl ratio, caspase 9 and caspase 3 mRNA expressions were significantly increased for 45 minutes of ODLG, but not for 30, 60, 75 and 90 minutes. Results showed that cell viability reduction in the spinal cord was dependent on ischemic time, resulting in glutamate and LDH release. ODLG for 45 minutes was adequate for gene expression evaluation of proteins and proteases involved in apoptosis pathways. 相似文献
64.
Rodolfo Fred Behrsin Cyro Teixeira da Silva Junior Gilberto Perez Cardoso Jorge Luiz Barillo Joeber Bernardo Soares de Souza Elizabeth Giestal de Araújo 《International journal of clinical and experimental pathology》2015,8(6):7239-7246
Introduction: Closed needle pleural biopsy (CNPB) has historically been the gold standard procedure for the diagnosis of pleural tuberculosis. Adenosine deaminase (ADA) is an efficient biomarker for tuberculosis that is measurable in pleural fluids. Objective: We compared the diagnostic accuracy of the pleural ADA (P-ADA) level and histopathological findings of CNPB specimens in patients with pleural tuberculosis. Methods: This prospective study consisted of two groups of examinations with a proven diagnosis of pleural effusion. The P-ADA level was measured in 218 patients with pleural effusion due to a number of causes, and 157 CNPB specimens underwent histopathological analysis. Results: CNPBs were performed in patients with tuberculosis (n=122) and other diseases: adenocarcinoma (n=23), lymphoma (n=5), systemic lupus erythematosus (n=4), squamous cell carcinoma (n=2), and small cell lung cancer (n=1). According to the ROC curve, the optimal cut-off value of the P-ADA level (Giusti and Galanti colorimetric method) was equal to or greater than 40.0 U/L. The diagnostic accuracy of the P-ADA test was 83.0%, and that of histopathological examination of the CNPB tissue, was 78.8% (AUC=0.293, P=0.7695). The association between the P-ADA assay and pleural histopathology was 24.41 (P<0.0001). The tetrachoric correlation coefficient was 0.563 (high correlation). Conclusion: In Brazil and other countries with a high incidence of tuberculosis, P-ADA activity is an accurate test for the diagnosis of tuberculous pleural effusions, and its use should be encouraged. The high diagnostic performance of the P-ADA test could to aid the diagnosis of pleural tuberculosis and render CNPB unnecessary. 相似文献
65.
Jacek B. Kowalczewski Luc Labey Yan Chevalier Tomasz Okon Bernardo Innocenti Johan Bellemans 《Archives of Medical Science》2015,11(2):311-318
Introduction
Correct restoration of the joint line is generally considered as crucial when performing total knee arthroplasty (TKA). During revision knee arthroplasty however, elevation of the joint line occurs frequently. The general belief is that this negatively affects the clinical outcome, but the reasons are still not well understood.Material and methods
In this cadaveric in vitro study the biomechanical consequences of joint line elevation were investigated using a previously validated cadaver model simulating active deep knee squats and passive flexion-extension cycles. Knee specimens were sequentially tested after total knee arthroplasty with joint line restoration and after 4 mm joint line elevation.Results
The tibia rotated internally with increasing knee flexion during both passive and squatting motion (range: 17° and 7° respectively). Joint line elevation of 4 mm did not make a statistically significant difference. During passive motion, the tibia tended to become slightly more adducted with increasing knee flexion (range: 2°), while it went into slighlty less adduction during squatting (range: –2°). Neither of both trends was influenced by joint line elevation. Also anteroposterior translation of the femoral condyle centres was not affected by joint line elevation, although there was a tendency for a small posterior shift (of about 3 mm) during squatting after joint line elevation. In terms of kinetics, ligaments lengths and length changes, tibiofemoral contact pressures and quadriceps forces all showed the same patterns before and joint line elevation. No statistically significant changes could be detected.Conclusions
Our study suggests that joint line elevation by 4 mm in revision total knee arthroplasty does not cause significant kinematic and kinetic differences during passive flexion/extension movement and squatting in the tibio-femoral joint, nor does it affect the elongation patterns of collateral ligaments. Therefore, clinical problems after joint line elevation are probably situated in the patello-femoral joint or caused by joint line elevation of more than 4 mm. 相似文献66.
Sinisa Vidovic Jeff Elder Prabhakara Medihala John R. Lawrence Bernardo Predicala Haixia Zhang Darren R. Korber 《Antimicrobial agents and chemotherapy》2015,59(6):3317-3328
In this study, we tested the antimicrobial activity of three metal nanoparticles (NPs), ZnO, MgO, and CaO NPs, against Salmonella enterica serovar Enteritidis in liquid medium and on solid surfaces. Out of the three tested metal NPs, ZnO NPs exhibited the most significant antimicrobial effect both in liquid medium and when embedded on solid surfaces. Therefore, we focused on revealing the mechanisms of surface-associated ZnO biocidal activity. Using the global proteome approach, we report that a great majority (79%) of the altered proteins in biofilms formed by Salmonella enterica serovar Enteritidis were downregulated, whereas a much smaller fraction (21%) of proteins were upregulated. Intriguingly, all downregulated proteins were enzymes involved in a wide range of the central metabolic pathways, including translation; amino acid biosynthetic pathways; nucleobase, nucleoside, and nucleotide biosynthetic processes; ATP synthesis-coupled proton transport; the pentose phosphate shunt; and carboxylic acid metabolic processes, indicating that ZnO NPs exert a panmetabolic toxic effect on this prokaryotic organism. In addition to their panmetabolic toxicity, ZnO NPs induced profound changes in cell envelope morphology, imposing additional necrotic effects and triggering the envelope stress response of Salmonella serovar Enteritidis. The envelope stress response effect activated periplasmic chaperones and proteases, transenvelope complexes, and regulators, thereby facilitating protection of this prokaryotic organism against ZnO NPs. 相似文献
67.
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69.
Marco Valgimigli Paolo Calabrò Bernardo Cortese Enrico Frigoli Stefano Garducci Paolo Rubartelli Giuseppe Andò Andrea Santarelli Mario Galli Roberto Garbo Alessandra Repetto Salvatore Ierna Carlo Briguori Ugo Limbruno Roberto Violini Andrea Gagnor 《Journal of cardiovascular translational research》2014,7(1):101-111
Early invasive management and the use of combined antithrombotic therapies have decreased the risk of recurrent ischaemia in patients with acute coronary syndrome (ACS) but have also increased the bleeding risk. Transradial intervention (TRI) and bivalirudin infusion compared to transfemoral intervention (TFI) or unfractionated heparin (UFH) plus glycoprotein IIb/IIIa inhibitors (GPI) decrease bleeding complications in patients with ACS. To what extent, a bleeding preventive strategy incorporating at least one of these two treatment options translates into improved outcomes is a matter of debate. The Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX study is a large-scale, multicenter, prospective, open-label trial, conducted at approximately 100 sites in Europe aiming to primarily assess whether TRI and bivalirudin infusion, as compared to TFI and UFH plus provisional GPI, decrease the 30-day incidence of death, myocardial infarction or stroke across the whole spectrum of ACS patients. 相似文献
70.
S. Baragou M. Pio S. Di Bernardo T. Boulos Ksontini S. Jiekak Dommange L. Bonafe E. Meijboom N. Sekarski 《Annales de cardiologie et d'angeiologie》2014