جستجوی مقالات مرتبط با کلیدواژه "immunoassay" در نشریات گروه "پزشکی"

 Wheat grains are susceptible to mycotoxins, toxic natural secondary metabolites generated by certain fungi on agricultural produce in the field during growth, harvest, transportation, or storage. Therefore, wheat flour can be contaminated with mycotoxins, which seriously threaten human health.

 A rapid method for screening seven mycotoxins in wheat flour was validated in accordance with Commission Decision 2002/657/EC. With this multi-analytical screening method, 7 prevalent mycotoxins (fumonisin B1, ochratoxin A, aflatoxin G1, deoxynivalenol, T-2 toxin, aflatoxin B1, and zearalenone) can be determined simultaneously. The method’s applicability was demonstrated by screening 7 mycotoxins in 39 wheat flour samples collected from different bakeries in Tehran province, Iran.

 The validation results indicated that for all 7 mycotoxins, the positivity threshold (T) was above the cut-off value (Fm), and no false positive results were obtained for any of the mycotoxins. The screening results of 12 packaged and 27 bulk wheat flour samples indicated that the concentrations of all mentioned mycotoxins were higher than the cut-off (in the relative light unit [RLU]), and all the samples were compliant.

 The present study revealed that the biochip-based technique is valid for identifying and assessing the levels of 7 mycotoxins in grain samples, such as wheat flour, at the measured validation concentrations. The method was simple, fast, and able to screen 7 mycotoxins simultaneously. The test process of the kit is easy to conduct, and the results are straightforward to interpret.

There is no consensus on the usefulness of toxicological analysis in the management of cases presenting to the Emergency Department (ED) with acute recreational toxicity. While in some centers urine samples are routinely analyzed, in others management is based on clinical interpretation and patient self-report on the drug(s) used. Most of the studies that investigated the role of toxicological analysis in this cohort have used urine for the drug testing. The aim of this study was to compare the drug(s) detected in blood samples analyzed by immunoassay (IA) with those self-reported by patients presenting to the ED with acute recreational drug toxicity. The data were collected from self-reported drug(s) in patients presenting to the ED with acute recreational drug toxicity and compared to the results of a serum Immunoassay which includes 20 different tests. There was weak agreement (kappa 0.2 - 0.5) with significant disagreement between IA self-report for most of the drug assays, including cocaine, pregabalin, cannabis, and methadone. The poorest agreement was seen for synthetic cannabinoids (kappa 0.04) and benzodiazepines (kappa 0.13). The only exceptions with good agreement and insignificant disagreement between self-report and IA were methamphetamines (kappa = 0.65) and opiates (kappa = 0.60). Poor agreement existed between the IA test results in blood and the self-reported data. Further studies comparing IA/self-report data to a gold-standard confirmatory mass spectrometry (MS)-based test are required to definitively address the role of analytical screening in the assessment of patients with acute recreational drug toxicity.

The serological measurement of the anti-hepatitis C virus antibody is a widely used tool in the first-line diagnosis of HCV infection. Therefore, increasing the testing criteria of these tests is of crucial importance for screening HCV infection.

The current study aimed to optimize a novel enzyme-linked immuno assay model to detect E2 antigen with or without sample pretreatment in combination with antibodies against core, NS3, NS4, and NS5 antigens of the hepatitis C virus and to compare the performances of these assays with indirect antigen (Ag), biotin/HRP labeled Antigen Sandwich andmethods of enzymelinked immunosorbent assay (ELISA) for their ability to detect HCV.

A total of 107 positive and 415 negative controls from volunteer whole blood donors in Blood TransfusionOrganization and 204 blood samples from patients under hemodialysis treatment in Tehran and Bandar Abbas hemodialysis centers are investigated. Six different methods of ELISA test were used to detect anti-HCV antibodies and/or HCV antigens in serum samples.

Regarding sensitivity, specificity, and accuracy, E2 Antigen detection alone or combined with antibody detection have the highest accuracy value (99% and 98%, respectively) compared to othermethods for antibodies detection. The results of the combined Ag/Ab ELISA test were closer to the results of real-time PCR.

This new approach to the detection of antigen and antigen/antibody has better performance criteria concerning the serologic detection of HCV, especially in HD patients who might experience a longer window period.

Cancer is known as a second-high fatal disease after cardiovascular disease in the world. Although many techniques have been investigated for the treatment of cancer, none of them satisfied completely. Investigation of a cancer diagnosis is the new pathway to cancer therapy. It has been known that cancer diagnosis at its early stage could help eradicate it in the patientchr(chr('39')39chr('39'))s body. Among different techniques that have been investigated for cancer diagnosis in its early stages, immune assay techniques due to high sensitivity and selectivity have been comprised. This review investigates new immune assay techniques and their combination with others as a new cancer diagnosis method.

This study investigated the presence of specific antibodies against Toxoplasma gondii infection among people with diabetes (type I and II) in comparison with control group. Overall 300 serum samples were collected equally from three groups including patients with type I and type II diabetes and non-diabetic healthy control that referred to Tabriz Central Laboratory in northwest Iran during July to Sep 2015. The level of specific IgG and IgM antibodies against T. gondii were measured using the chemiluminescence immunoassay (CLIA) method. Chi-square and One-Way ANCOVA were used for data analysis. Overall, 300 samples from diabetic patients (type I and type II) and control group were examined and results showed 3, 8 and 2 cases were seropositive for anti- T. gondii IgM respectively. Anti- T. gondii IgG seropositivity in type I and type II diabetes and control groups were 69%, 63% and 59% respectively. We did not observe any statistical differences among all studied groups in terms of toxoplasmosis. There was no statistically significant relationship between all variables and seropositivity for anti-T. gondii antibodies in type I and II diabetes and non-diabetic groups. Although there was no statistically significant relationship between diabetes and toxoplasmosis further investigations especially experimental studies using animal models are needed. Furthermore, these findings would not be contrary to the need for healthcare in order to the prevention of infectious disease in diabetic patients.

The production of human thyroid stimulating hormone (hTSH) immunoassays requires specific antibodies against hTSH which is a cumbersome process. Therefore, producing specific polyclonal antibodies against engineered recombinant fusion hTSH antigens would be of great significance. The best immunogenic region of the hTSH was selected based on in silico analyses and equipped with two different fusions. Standard methods were used for protein expression, purification, verification, structural evaluation, and immunizations of the white New Zealand rabbits. Ultimately, immunized serums were used for antibody titration, purification and characterization (specificity, sensitivity and cross reactivity). The desired antigens were successfully designed, sub-cloned, expressed, confirmed and used for in vivo immunization. Structural analyses indicated that only the bigger antigen has showed changed 2 dimensional (2D) and 3D structural properties in comparison to the smaller antigen. The raised polyclonal antibodies were capable of specific and sensitive hTSH detection, while the cross reactivity with the other members of the glycoprotein hormone family was minimum and negligible. The fusion which was solely composed of the tetanus toxin epitopes led to better protein folding and was capable of immunizing the host animals resulting into high titer antibody. Therefore, the minimal fusion sequences seem to be more effective in eliciting specific antibody responses.

Interfering antibodies are capable of causing potentially misleading results in automated thyroid hormone immunoassays..
We report the case of a 46- year-old female patient with autoimmune hypothyroidism in chronic replacement treatment with levothyroxine who was presented 8 years after diagnosis with a thyroid function test showing an increased level of TSH and a very high level of FT4. Interference in the laboratory serum free thyroxin (FT4) test was suspected, due to the lack of symptoms of hyperthyroidism and a different immunoassay platform confirmed a low FT4 result. The discrepancy between the two results was explained by the presence of antiT4-autoantibodies..
Antibody interference with serum free thyroxine must be considered when clinical findings and laboratory results show discrepancies..

Some nanoparticles can be used in immunoassays to increase sensitivity. This study aimed to evaluate a novel nano-immunoassay based on bovine serum albumin nanoparticles (BSA NPs).
At first, the nanostructure was synthesized, and then applied as a tag in the nano-immunoassay. Then the concentration of β-subunit of human chorionic gonadotropin (βHCG) in the clinical samples was quantified by traditional enzyme-linked immunosorbent assay (ELISA), and then checked by the nano-immunoassay.
The Pearson’s correlation coefficient between ELISA and nano-immunoassay was high, i.e., 0.80. Relative sensitivity and specificity of this nano-immunoassay were reported 97.4% and 96.6%, respectively.
BSA NPs can be applied in nano-immunoassays as a new structure, and as an example, βHCG can be detected by this novel assay.

To evaluate the effects of silver nanoparticles on some serum parameters in mice. Forty mice, including twenty male and twenty female, were randomly divided into eight groups: C1 and C2 (male and female control groups, respectively), T1, T2 and T3 (male treatment groups), T4, T5 and T6 (female treatment groups). After the acclimatization period, the treatment groups were gavaged for 15 days with silver nanoparticles solution, whose daily dose was 3 mg/kg for T1 and T4 groups, 300 mg/kg for T2 and T5 groups, and 1000 mg/ kg for T3 and T6 groups. Then, serum samples were collected and tested for total cholesterol, triglyceride, urea and creatinine by the enzyme-linked immunosorbent assay (ELISA) method. While the serum urea levels were noticeably high among T4 and T6 groups (P =. 05), they were significantly lower in T2 and T3 groups (P =. 05). All serum triglyceride levels in T1, T2, T3, T4 and T5 groups were considerably low (P =. 05). There were no significant differences in serum creatinine levels between the groups (P =. 05). The serum cholesterol levels were significantly low in T1 and T4 groups, however they were pointedly higher in T2 and T6 groups (P =. 05). No change in serum creatinine levels, positive decrease in serum triglyceride levels, erratic alteration in serum cholesterol levels and different effect of silver nanoparticles on serum urea levels in female and male mice were found in this study.

Context: Viral hepatitis diagnosis is an important issue in the treatment procedure of this infection. Late diagnosis and delayed treatment of viral hepatitis infections can lead to irreversible liver damages and occurrence of liver cirrhosis and hepatocellular carcinoma. A variety of laboratory methods including old and new technologies are being applied to detect hepatitis viruses. Here we have tried to review, categorize, compare and illustrate the classical and modern approaches used for diagnosis of viral hepatitis..Evidence Acquisition: In order to achieve a comprehensive aspect in viral hepatitis detection methods, an extensive search using related keywords was done in major medical library and data were collected, categorized and summarized in different sections.. Analyzing of collected data resulted in the wrapping up the hepatitis virus detection methods in separate sections including 1) immunological methods such as enzyme immunoassay (EIA), radio-immunoassay (RIA) immuno-chromatographic assay (ICA), and immuno-chemiluminescence 2) molecular approaches including non-amplification and amplification based methods, and finally 3) advanced biosensors such as mass-sensitive, electrical, electrochemical and optical based biosensors and also new generation of detection methods.. Detection procedures in the clinical laboratories possess a large diversity; each has their individual advantages and facilities'' differences..

Enzyme Linked ImmunoSorbent Assay (ELISA) has been described as analternative to radioimmunoassay for the mammalian and nonmammalian steroids detection. Inthis study, a simple and rapid ELISA is described and validated for 4-pregnen-3,20, dione(progesterone).

A general procedure for preparation of the acetylcholinesteraselabelled steroid is described which is applicable to any steroid. Use of acetylcholinesterasetracer increased the sensitivity of assay so that reliable measurements of each steroid could beachieved with only 10 μl of plasma.

Typical standard curves for progesterone steroids showed a workable range(detection limit) from 0.8 to 400 pg/well and the sensitivity of the assay taken as theconcentration of steroid that induced 90% of B/B0, was 1.5 pg. Inter-assay variations that gaveapproximately 50% displacement was 9.2% for 10 replicates and intra-assay co-efficient ofvariation was less than 10% over the central part of the standard curve between 3 and 200pg/well. There was a strong positive correlation (r>0.999) between the amount of steroidadded to plasma and the amount measured.

Method described here was applied to measure progesterone in plasma and thismethodology could be of great interest to researchers measuring steroid hormones.