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Definition of the Nature and Hapten Threshold of the β-Lactam Antigen Required for T Cell Activation In Vitro and in Patients
Abstract<p>Covalent modification of protein by drugs may disrupt self-tolerance, leading to lymphocyte activation. Until now, determination of the threshold required for this process has not been possible. Therefore, we performed quantitative mass spectrometric analyses to define the epitopes formed in tolerant and hypersensitive patients taking the β-lactam antibiotic piperacillin and the threshold required for T cell activation. A hydrolyzed piperacillin hapten was detected on four lysine residues of human serum albumin (HSA) isolated from tolerant patients. The level of modified Lys541 ranged from 2.6 to 4.8%. Analysis of plasma from hypersensitive patients revealed the same pattern and levels of modification 1–10 d after the commencement of therapy. Piperacillin-responsive skin-homing CD4+ clones expressing an array of Vβ receptors were activated in a dose-, time-, and processing-dependent manner; analysis of incubation medium revealed that 2.6% of Lys541 in HSA was modified when T cells were activated. Piperacillin–HSA conjugates that had levels and epitopes identical to those detected in patients were shown to selectively stimulate additional CD4+ clones, which expressed a more restricted Vβ repertoire. To conclude, the levels of piperacillin–HSA modification that activated T cells are equivalent to the ones formed in hypersensitive and tolerant patients, which indicates that threshold levels of drug Ag are formed in all patients. Thus, the propensity to develop hypersensitivity is dependent on other factors, such as the presence of T cells within an individual’s repertoire that can be activated with the β-lactam hapten and/or an imbalance in immune regulation.</p>
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Publication Date
Mon Jan 02 2006
Journal Name
Journal Of The Faculty Of Medicine Baghdad
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Publication Date
Fri Dec 31 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
SYNTHESIS AND CHARACTERIZATION OF NEW β-LACTAM DERIVATVE FROM SULFADIAZINE DRUG BY MANY STEPS: SYNTHESIS AND CHARACTERIZATION OF NEW β-LACTAM DERIVATVE FROM SULFADIAZINE DRUG BY MANY STEPS

This research involved synthesis of new β-Lactam derivative from Azo compound[4-amino-N-(pyrimidine-2-yl)-3-(pyrimidine-2-yldiazenyl) benzene sulfonamide] (S1) record previously by many steps. Starting conversion the free amino group in an azo comp. to chloro acetamide derivative(S2), then reacted it with urea to give the oxazole ring  derivative (S3) that which containing free amino group. The condensation reaction between the amino group and P-bromobenzaldehyde to produce Shiff base (B14). Finally staudinger's cyclo addition reaction go run between the Shiff base derivative (B14) and chloro acetyl chloride in the presence of tri ethyl amine (Et3N) as Base catalyst and dioxane a

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Publication Date
Wed Jan 02 2008
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Genetic characteristics and β-cell Autoimmunity in T1DM Children

Background: TIDM is known to be polygenic disease that appears from the interaction of mutation in multiple genes including HLA. The autoimmune mediated destruction of
pancreatic β-cells is reflected by the presence of autoantibodies against prominent antigens in the pancreatic β-cells.
Objective: This study was designed to investigate the role of HLA-class I and class II antigens in the etiology of type 1 diabetes mellitus (T1DM) and also assessment of
glutamic acid decarboxylase (GAD65) autoantibodies in the patients at the onset of the disease.
Patients & Methods: Sixty T1DM patients who were newly onset of the disease (diagnosed less than five months) were selected. Eighty apparently healthy

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Publication Date
Wed Mar 27 2013
Journal Name
Journal Of University Of Babylon
Reduce the required time for measuring the permeability of clayey soils by using new manufactured cell

Reduce the required time for measuring the permeability of clayey soils by using new manufactured cell

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Publication Date
Tue Aug 15 2017
Journal Name
Journal Of Immunology
The Effect of Inhibitory Signals on the Priming of Drug Hapten–Specific T Cells That Express Distinct Vβ Receptors
Abstract<p>Drug hypersensitivity involves the activation of T cells in an HLA allele–restricted manner. Because the majority of individuals who carry HLA risk alleles do not develop hypersensitivity, other parameters must control development of the drug-specific T cell response. Thus, we have used a T cell–priming assay and nitroso sulfamethoxazole (SMX-NO) as a model Ag to investigate the activation of specific TCR Vβ subtypes, the impact of programmed death -1 (PD-1), CTL-associated protein 4 (CTLA4), and T cell Ig and mucin domain protein-3 (TIM-3) coinhibitory signaling on activation of naive and memory T cells, and the ability of regulatory T cells (Tregs) to prevent responses. An expa</p> ... Show More
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Publication Date
Sun Jul 01 1990
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
THE ROLE OF SPECIFIC AMINO ACIDS IN THE PROTECTION OF E. COLI AGAINST B-LACTAM ANTIBIOTICS IN VITRO

The role of specific amino acids namely cysteine, methionine, threonine and asparagine in the protection provided by vamin solution against B-lactam inhibition to E. coli was evaluated in vitro In minimal medium, cells were treated with 32 ug/ml of penicillin G, carbenciLlin, hostacillin, cloxacillin and cephalotin in the presence of specific amino acid supplementation. Deletion of specific amino acids from the media abolished the protection provided by vamin. Threonine was essential for the protection of cells against all tested antibiotics, while cysteine was essential for protection against carbencillin and sephalotin. Deletion of methionine or asparagine abolished the protection against carbencillin and to a less extent cephalotin.

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Publication Date
Thu Jun 30 2022
Journal Name
International Journal Of Drug Delivery Technology
Synthesis, Characterization of New Sulfamethoxazole Derivatives containing β-lactam Ring and Preliminary Evaluation of their Antimicrobial Activity

Sulfamethoxazole (SMX) is the most significant antibiotic in the sulfonamide family. It was chosen as the representative of this category because of its widespread use. Starting with sulfamethoxazole, a new series of 2-Azetidinone (M1-M6) was synthesized, the structure of these new derivatives was confirmed using spectral methods, starting with the synthesis of Schiff’s bases by reflux of different aromatic benzaldehydes, separately, with Sulfamethoxazole in ethanol with few drops of acetic acid. The final compounds were obtained by ketene-imine synthesis of β-lactam using chloroacetyl chloride. The designed chemicals’ synthesis has been completed successfully. Physical parameters (melting points and Rf values), Fourier transfo

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Publication Date
Fri Nov 01 2019
Journal Name
Indian Journal Of Public Health Research & Development
Prevalence of β-lactam Resistant Klebsiella Pneumoniae Isolates among Clinical Specimensin Baghdad Hospitals

One hundred forty three of Klebsiellapneumoniae isolates had been collected from some hospitals in Baghdad city. The isolates were taken from different clinical specimens.Antimicrobial susceptibility test was carried out towards fifteen antimicrobial agents by using Vitek2 system with Antimicrobial susceptibility test cards. The results of antibiogram showed that the local isolates were possess highly resistance towards most antimicrobial agents under study. The high resistance wastoAmpicillin while the low resistance was to Imipenem.Two methods were used for detection of Extended Spectrum Beta Lactamases (ESBLs) production; first methods by using of Vitek2 system,thesecondmethods by using of polymerase chain reaction (PCR) technique to dis

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Publication Date
Sun Mar 13 2011
Journal Name
Baghdad Science Journal
The Effect of Silybum marianum L. aquatic crude extracts on the cancer cell lines and normal cell line in vitro

The aquatic crude extract of Silybum marianum dry grains prepared by melting them in distil water by the method of soak and shake. The effect of Silybum marianum crude extract studied in vitro on three tumor cell line the Hep-2, AMN-3 and RD for 24, 48 and 72 hours of exposure, and one cell line of normal cells REF for 72 hr exposure. The results showed that the prescence of toxic effect of the aquatic crude extract on the cell lines of Hep-2, AMN-3 and RD at 10 and 100 µg/ ml upto the higher concentrations when they exposed to the extract for 48 hr. as compared with the control treatment, and when the exposure period increased to 72 hr. the toxic effect started at low concentrations (5 and 10 µg/ ml) as compared with the control g

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Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Educational And Psychological Researches
Teaching Competencies Required For Teachers of History in the Preparatory Stage

         This study attempts to determine the necessary teaching competencies for teachers and the level of their importance in the development of their performance professionally and scientifically, and the progress towards a better future to achieve an effective level. Accordingly, the research community consists of the morning-preparatory schools for boys at the General Directorate of Education of Baghdad \ Rusafa2. The study sample included (68) teachers constituted 88.31% of the total community of teachers. As for the research tools, the researcher adopted the descriptive method by using the observation method in which the researcher prepared a list of teaching. For verifying the re

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