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1.
Nitsa Buaron Antonella Mangraviti Francesco Volpin Ann Liu Mariangela Pedone Eric Sankey Dina Aranovich Itay Adar Fausto J. Rodriguez Abraham Nyska Riki Goldbart Tamar Traitel Henry Brem Betty Tyler Joseph Kost 《Advanced functional materials》2021,31(44):2100643
Treating neuroinflammation-related injuries and disorders through manipulation of neuroinflammation functions is being heralded as a new therapeutic strategy. In this study, a novel pectic galactan (PG) polysaccharide based gene therapy approach is developed for targeting reactive gliosis in neuroinflammation. Galectin-3 (Gal-3) is a cell protein with a high affinity to β-galactoside sugars and is highly expressed in reactive gliosis. Since PG carries galactans, it can target reactive gliosis via specific carbohydrate interaction between galactan and Gal-3 on the cell membrane, and therefore can be utilized as a carrier for delivering genes to these cells. The carrier is synthesized by modifying quaternary ammonium groups on the PG. The resulting quaternized PG (QPG) is found to form complexes with plasmid DNA with a mean diameter of 100 nm and have the characteristics required for targeted gene therapy. The complexes efficiently condense large amounts of plasmid per particle and successfully bind to Gal-3. The in vivo study shows that the complexes are biocompatible and safe for administration and can selectively transfect reactive glial cells of an induced cortical lesion. The results confirm that this PG-based delivery system is a promising platform for targeting Gal-3 overexpressing neuroinflammation cells for treating neuroinflammation-related injuries and neurodegenerative diseases. 相似文献
2.
Application of high‐temperature Fenton oxidation for the treatment of sulfonation plant wastewater
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3.
C Harro GL Braden AB Morris GS Lipkowitz RL Madden 《Canadian Metallurgical Quarterly》1997,24(5):955-957
Nontuberculous mycobacteria are increasingly recognized as important pathogens in peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD). Mycobacterium gordonae rarely causes human infection and is the least likely mycobacterium to produce clinical infection in CAPD patients. We describe a patient with persistent M. gordonae peritonitis acquired while undergoing CAPD. During 18 months of treatment, clinical improvement occurred but a microbiological cure could not be achieved. Principles of therapy for mycobacterial peritonitis developing during CAPD are reviewed, and potential explanations for our patient's failure to respond to therapy are discussed. 相似文献
4.
GS Kelner JM Minnerath MK Jenkins R Jemmerson 《Canadian Metallurgical Quarterly》1993,23(8):1992-1998
Male and female A/J mice were examined for their ability to elicit T lymphocyte and antibody (Ab) responses to the male-specific Ag, mouse testicular cytochrome c (Mt cyt). T lymphocytes from both male and female mice primed in vivo responded to the Ag in in vitro proliferation assays, and the dose-response curves were statistically indistinguishable. In addition, similar levels of Ab to Mt cyt were observed in immunized male and female mice. The B cells producing the Ab had switched isotypes to IgG1 and IgG2a, indicating that the self-reactive T helper (Th) cells in male mice were functional. Thus, male mice do not appear to be immunologically tolerant to Mt cyt, at least at the Th and B lymphocyte levels. No evidence for disease was found in male mice primed with Mt cyt. Major histocompatibility complex (MHC) class II-positive antigen-presenting cells are present in the testes and these were shown in vitro to process and present Mt cyt to a T cell hybridoma specific for the synthetic peptide Mt cyt 93-104. However, the hybridoma was not activated in the absence of exogenous Mt cyt 93-104 or Mt cyt, indicating that endogenous Mt cyt is not normally processed in sufficient quantity to effectively load MHC class II molecules with this particular Mt cyt-derived peptide. Notwithstanding any immunologic privilege of the testes, the lack of tolerance to Mt cyt and its failure to elicit an autoimmune disease could extend from the low levels of processed Mt cyt Ag available for T cell recognition. The T cell response elicited by Mt cyt contrasts the lack of response to mouse somatic cytochrome c which differs from Mt cyt at 13 amino acid residues and is expressed in most tissues and at higher levels. 相似文献
5.
There is growing evidence that the amino-terminal globular domain of apolipoprotein B (apoB) is essential for lipoprotein particle formation in the hepatic endoplasmic reticulum. To identify the structural requirements for its function in lipoprotein assembly, cysteine (Cys) pairs required to form the seven disulfide bonds within the amino-terminal 21% of apoB were replaced in groups or individually by serine. Substitution of Cys pairs required for formation of disulfide bonds 1-3 or 4-7 (numbered from amino to carboxyl terminus) completely blocked the secretion of apoB28 in transfected HepG2 cells. To identify the specific disulfide bonds required for secretion, Cys pairs were mutated individually. Substitution of Cys pairs required for disulfide bonds 1, 3, 5, 6, or 7 had little or no impact on apoB28 secretion or buoyant density. In contrast, individual substitution of Cys pair 2 (amino acid residues 51 and 70) or 4 (218 and 234) severely inhibited apoB28 secretion and its capacity to undergo intracellular assembly with lipid. The same assembly and secretion defects were observed when these mutations were expressed as part of apoB50. These studies provide direct evidence that the ability of the internal lipophilic regions of apoB to engage in the recruitment and sequestration of lipid during translation is critically dependent upon a structural configuration contained within or affected by the amino-terminal 5% of the protein. 相似文献
6.
DH Kang CL Coe DO McCarthy NN Jarjour EA Kelly RR Rodriguez WW Busse 《Canadian Metallurgical Quarterly》1997,17(8):481-487
T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation. 相似文献
7.
Previous studies in children have shown inconsistent, poorly reproducible GH responses to exogenous GH-releasing factor (GRF), with wide individual variability. In the present study, we tested the hypothesis that prior administration of the long-acting somatostatin analog, SMS 201-995 (SMS), will enhance GH responsiveness to a subsequent GRF challenge. Two study protocols were employed in 37 children with short stature [M = 31, F = 6, ages 11.8 +/- 1.6 yr (mean +/- SEM), height -2.25 +/- 0.55 SDS (SD scores)]. In both studies, each subject served as his/her own control. In the first study, which was designed to determine optimal SMS dose and regimen, SMS, in doses ranging from 0.8-2.2 micrograms/kg sc, was randomly administered or omitted at 0800 h after an overnight fast, and a GRF bolus (50 micrograms, iv) was given 4 h later. In the second study, we employed a protocol identical to study 1 except for the use of standard doses of SMS (1 microgram/kg, sc) and GRF (1 microgram/kg, iv) and an additional 1-h delay of the GRF injection. Plasma GH levels were measured every 20 min from 0800 h until 2 h after the GRF injection in both studies. In study 1 (n = 12; M = 10, F = 2), SMS significantly suppressed spontaneous GH secretion (expressed as the mean +/- SEM GH AUC during the 4-h SMS-GRF interval, AUC 1:2.2 +/- 0.4 vs. 6.2 +/- 0.9 micrograms/L.h; P < 0.001), GH responsiveness to GRF (GH AUC during the 2 h after the GRF injection, AUC 2: 41.5 +/- 7.8 vs. 85.0 +/- 13.5 micrograms/L.h; P < 0.001), and the GH peak response (17.4 +/- 3.1 vs. 36.0 +/- 6.2 micrograms/L; P < 0.001), compared to control tests. In contrast, in study 2 (n = 25; M = 21, F = 4), whereas spontaneous GH secretion was still suppressed during the 5-h SMS-GRF interval (AUC 1:3.8 +/- 0.4 vs. 7.4 +/- 1.1 micrograms/L.h; P < 0.001), both the GH peak response (56.7 +/- 5.5 vs. 30.5 +/- 3.0 micrograms/L; P < 0.0001) and the GH AUC (AUC 2: 103.7 +/- 10.3 vs. 77.5 +/- 6.8 micrograms/L.h; P < 0.05) after GRF administration were significantly augmented by pretreatment with SMS, compared to control tests. Taken together, these results indicate that a priming SMS dose of 1 microgram/kg has a significant permissive effect on GH responsiveness to exogenous GRF administered 5 h later.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
8.
E La Hey J de Vries CT Langerhorst GS Baarsma A Kijlstra 《Canadian Metallurgical Quarterly》1993,116(3):327-340
After reviewing the records of 111 patients with Fuchs' heterochromic iridocyclitis, we studied the therapy and prognosis of secondary glaucoma in 30 of these 111 patients (27%) who had glaucoma or could be considered glaucoma suspects. Maximal medical therapy was unsuccessful in 22 of the 30 patients (73%). Surgical intervention (mostly trabeculectomies, half with 5-fluorouracil) successfully controlled intraocular pressure (< or = 21 mm Hg with or without medication) in 13 of the 18 operated-on patients (72%) after a mean follow-up of 26 months. All successfully operated-on patients retained a visual acuity of 20/80 or better. We had favorable results, possibly because of modern surgical techniques (use of 5-fluorouracil, sodium hyaluronate) or earlier surgical intervention, or both. 相似文献
9.
Murad Nour Mohammad Belfiore Jean Claude Guisantes George Rodriguez 《Wireless Personal Communications》2002,20(2):145-161
In DS-WCDMA mobile systems such the UMTS, asynchronous cell site operation,assigning different long spreading code to each cell, yields the advantageof flexible system deployment. We can design an indoor system basedon an outdoor one. However, in general, much longer search time isrequired in asynchronous operation than in synchronous. This paperproposes three techniques to take decisions about synchronizationbased on observation of correlated signals. Classical decision criterialike maximum and threshold criterion are presented. A new decisioncriteria that we call Threshold&Max combined decision criteriais analyzed. The results of this new introduced technique is comparedwith the classical ones. 相似文献
10.
Norris Fran H.; Murphy Arthur D.; Baker Charlene K.; Perilla Julia L.; Rodriguez Francisco Gutiérrez; Rodriguez José de Jesús Gutiérrez 《Canadian Metallurgical Quarterly》2003,112(4):646
Prevalence rates of trauma and posttraumatic stress disorder (PTSD) were estimated from a probability sample of 2,509 adults from 4 cities in Mexico. PTSD was assessed according to Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) criteria using the Composite International Diagnostic Interview (CIDI; WHO, 1997). Lifetime prevalence of exposure and PTSD were 76% and 11.2%, respectively. Risk for PTSD was highest in Oaxaca (the poorest city), persons of lower socioeconomic status, and women. Conditional risk for PTSD was highest following sexual violence, but nonsexual violence and traumatic bereavement had greater overall impact because of their frequency. Of lifetime cases, 62% became chronic; only 42% received medical or professional care. The research demonstrates the importance of expanding the epidemiologic research base on trauma to include developing countries around the world. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献