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Glial activation and oxidative-nitrative stress occur at an early stage in Alzheimer's disease (AD). In a rat model of AD, deficits in cerebral glucose utilization and memory were seen 3-4 weeks after intracerebroventricular (icv) injection of streptozotocin (STZ). This study examined whether icv STZ induced glial activation and oxidative-nitrative stress preceded the memory deficits and whether they could be prevented by ladostigil a novel drug, a cholinesterase and monoamine oxidase inhibitor with neuroprotective activity. One week after STZ injection activated microglia and astrocytes were seen in the cortex, around the cannula penetration area, in the hippocampal CA1 region, corpus callosum, medial and lateral septum. The activated astrocytes showed a significant increase in nitrotyrosine immunoreactivity, a measure of oxidative-nitrative stress. Only 3 weeks later were deficits in episodic (object recognition test) and spatial memory (place recognition) seen in STZ-injected rats. Daily oral administrations of ladostigil (1mg/kg) for 1 week, before and after STZ prevented the glial changes, increase in nitrotyrosine immunoreactivity and memory deficits. Taken together the data support the role of glial activation and oxidative-nitrative stress in discrete brain areas in the aetiology of memory deficits and indicate a potential mechanism for their prevention by drug treatment. 相似文献
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Alexandra Corina Faur Daniela Cornelia Lazar Laura Andreea Ghenciu 《World journal of gastroenterology : WJG》2023,29(12):1811-1823
Pancreatic cancer (PC) has a low incidence rate but a high mortality, with patients often in the advanced stage of the disease at the time of the first diagnosis. If detected, early neoplastic lesions are ideal for surgery, offering the best prognosis. Preneoplastic lesions of the pancreas include pancreatic intraepithelial neoplasia and mucinous cystic neoplasms, with intraductal papillary mucinous neoplasms being the most commonly diagnosed. Our study focused on predicting PC by identifying early signs using noninvasive techniques and artificial intelligence (AI). A systematic English literature search was conducted on the PubMed electronic database and other sources. We obtained a total of 97 studies on the subject of pancreatic neoplasms. The final number of articles included in our study was 44, 34 of which focused on the use of AI algorithms in the early diagnosis and prediction of pancreatic lesions. AI algorithms can facilitate diagnosis by analyzing massive amounts of data in a short period of time. Correlations can be made through AI algorithms by expanding image and electronic medical records databases, which can later be used as part of a screening program for the general population. AI-based screening models should involve a combination of biomarkers and medical and imaging data from different sources. This requires large numbers of resources, collaboration between medical practitioners, and investment in medical infrastructures. 相似文献
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Gluhovschi C Gluhovschi G Herman D Potencz E Trandafirescu V Schiller A Petrica L Velciov S Bozdog G Bob F Muntean C Vernic C Guset V Cioca D 《International immunopharmacology》2007,7(9):1265-1270
Steroids are still the mainstay of therapy in primary chronic glomerulonephritis (PCGN), regardless of underlying disturbance or pathology. Moreover, relationship between known abnormalities and disease manifestation is stochastic, therefore treatment continues to be empirical. It is not known whether responsiveness is related to immune phenotype. We performed flowcytometric lymphocyte (Ly) phenotyping (CD19, CD3, CD3CD4, CD3CD8, CD56/16) on 16 patients (pts) (12M, 4F), mean age 37.6+/-13 years with primary chronic glomerulonephritis (PCGN): minimal change disease (MCD)--6 pts, focal and segmental glomerulosclerosis (FSGS)--4 pts, mesangial proliferative glomerulonephritis--5 pts, mesangiocapillary glomerulonephritis--1 pt, before and at 7 days of oral Prednisone 1 mg/kg/day (in 2 divided doses). Before steroids: 4/16 pts(25%) had elevated BP; 9/16(56.2) showed nephrotic proteinuria. Serum creatinine was >1.2 mg% in 6/16(37.5%). At 7 days WBC count increased (13,079.37+/-4966.4/microl vs. 8021.25+/-2077.4/microl; p=0.0007), Ly percentage (%) decreased (20.30+/-9% vs. 29.9+/-10.4%; p=0.0095), while absolute (abs.) Ly count remained unchanged. Both CD19 Ly% and CD19 Ly abs. count increased (16.13+/-6.5% vs. 9.52+/-3.7%; p=0.0015, and 410.012+/-29.7/microl vs. 223.56+/-123.8/microl; p=0.0077, respectively). NK (natural killer)% decreased (9.15+/-5.2% vs. 14.19+/-7.1%; p=0.0296). CD3, CD3CD4, CD3CD8 Ly subsets and CD4/CD8 ratio showed no change. Variation in proteinuria (2.88+/-2.1 g/24 h vs. 3.45+/-1.7 g/24 h; p=0.4) did not reach statistical significance (Wilcoxon-Mann-Whitney). In 11 pts we performed an additional analysis at 1 month. Compared to levels before steroids, there was an increase in WBC, CD19 Ly% and CD19 Ly abs. count and a decrease in NK% and NK abs. count. Other Ly subsets and CD4/CD8 ratio remained unchanged. Variation in clinical parameters (proteinuria, serum Creatinine, BP) did not reach statistical significance. Changes in Ly profile precede changes in clinical parameters and thus are divergent. While our patients proved to be early non-responders, further studies to elucidate whether profile changes provide for response specification are warranted. 相似文献
95.
Immunochemical detection of sulfur mustard adducts with keratins in the stratum corneum of human skin. 总被引:1,自引:0,他引:1
Govert P van der Schans Daan Noort Roos H Mars-Groenendijk Alex Fidder Lai F Chau Leo P A de Jong Hendrik P Benschop 《Chemical research in toxicology》2002,15(1):21-25
As part of a program to develop methods for diagnosis of exposure to chemical warfare agents, we developed immunochemical methods for detection of adducts of sulfur mustard to keratin in human skin. Three partial sequences of keratins containing glutamine or asparagine adducted with a 2-hydroxyethylthioethyl group at the omega-amide function were synthesized and used as antigens for raising antibodies. After immunization, monoclonal antibodies were obtained with affinity for keratin isolated from human callus exposed to 50 microM sulfur mustard. These antibodies showed binding to the stratum corneum of human skin exposed to low levels of sulfur mustard, as evidenced by immunofluorescence microscopy. This approach opens the way for development of a detection kit that can be applied directly to the skin. To the best of our knowledge, this is the first example of immunochemical detection of adduct formation of toxic chemicals with skin proteins. A similar approach can be followed for skin exposure to environmental pollutants. 相似文献
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Compartmental Pharmacokinetics and Tissue Drug Distribution of the Pradimicin Derivative BMS 181184 in Rabbits
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Andreas H. Groll Tin Sein Vidas Petraitis Ruta Petraitiene Diana Callender Corina E. Gonzalez Neelam Giri John Bacher Stephen Piscitelli Thomas J. Walsh 《Antimicrobial agents and chemotherapy》1998,42(10):2700-2705
The pharmacokinetics of the antifungal pradimicin derivative BMS 181184 in plasma of normal, catheterized rabbits were characterized after single and multiple daily intravenous administrations of dosages of 10, 25, 50, or 150 mg/kg of body weight, and drug levels in tissues were assessed after multiple dosing. Concentrations of BMS 181184 were determined by a validated high-performance liquid chromatography method, and plasma data were modeled into a two-compartment open model. Across the investigated dosage range, BMS 181184 demonstrated nonlinear, dose-dependent kinetics with enhanced clearance, reciprocal shortening of elimination half-life, and an apparently expanding volume of distribution with increasing dosage. After single-dose administration, the mean peak plasma BMS 181184 concentration (Cmax) ranged from 120 μg/ml at 10 mg/kg to 648 μg/ml at 150 mg/kg; the area under the concentration-time curve from 0 to 24 h (AUC0–24) ranged from 726 to 2,130 μg · h/ml, the volume of distribution ranged from 0.397 to 0.799 liter/kg, and the terminal half-life ranged from 4.99 to 2.31 h, respectively (P < 0.005 to P < 0.001). No drug accumulation in plasma occurred after multiple daily dosing at 10, 25, or 50 mg/kg over 15 days, although mean elimination half-lives were slightly longer. Multiple daily dosing at 150 mg/kg was associated with enhanced total clearance and a significant decrease in AUC0–24 below the values obtained at 50 mg/kg (P < 0.01) and after single-dose administration of the same dosage (P < 0.05). Assessment of tissue BMS 181184 concentrations after multiple dosing over 16 days revealed substantial uptake in the lungs, liver, and spleen and, most notably, dose-dependent accumulation of the drug within the kidneys. These findings are indicative of dose- and time-dependent elimination of BMS 181184 from plasma and renal accumulation of the compound after multiple dosing. 相似文献
100.
Balan C Balut C Gheorghe L Gheorghe C Gheorghiu E Ursu G 《Clinical hemorheology and microcirculation》2004,30(3-4):359-364
The paper is concerned with the determination of blood permittivity and conductivity in Poiseuille and Couette simple shear flows. The experimental procedure, based on dielectric spectroscopy, evidences the sensitivity of blood electric properties to the applied frequency and local shear rate magnitude. The method evidences the possibility to correlate (for well-defined flow geometry) magnitude of shear rate, and consequently the shear stress level, with spectra permittivity of blood. 相似文献