scholarly journals Optical Density Optimization of Malaria Pan Rapid Diagnostic Test Strips for Improved Test Zone Band Intensity

Diagnostics ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 880
Author(s):  
Prince Manta ◽  
Rupak Nagraik ◽  
Avinash Sharma ◽  
Akshay Kumar ◽  
Pritt Verma ◽  
...  
Keyword(s):  
Infectious Diseases ◽  
Optical Density ◽  
Protein Concentration ◽  
Average Diameter ◽  
Band Intensity ◽  
Visual Interpretation ◽  
Test Kit ◽  
Malaria Antigen ◽  
Test Zone ◽  
Membrane Coating

For the last few decades, the immunochromatographic assay has been used for the rapid detection of biological markers in infectious diseases in humans and animals The assay, also known as lateral flow assay, is utilized for the detection of antigen or antibody in human infectious diseases. There are a series of steps involved in the development of these immuno-chromatographic test kits, from gold nano colloids preparation to nitrocellulose membrane coating (NCM). These tests are mostly used for qualitative assays by a visual interpretation of results. For the interpretation of the results, the color intensity of the test zone is therefore very significant. Herein, the study was performed on a malaria antigen test kit. Several studies have reported the use of gold nanoparticles (AuNPs) with varying diameters and its binding with various concentrations of protein in order to optimize tests. However, none of these studies have reported how to fix (improve) test zone band intensity (color), if different sized AuNPs were synthesized during a reaction and when conjugated equally with same amount of protein. Herein, different AuNPs with average diameter ranging from 10 nm to 50 nm were prepared and conjugated equally with protein concentration of 150 µg/mL with KD = 1.0 × 10−3. Afterwards, the developed kits’ test zone band intensity for all different sizes AuNPs was fixed to the same band level (high) by utilization of an ultraviolet-visible spectrophotometer. The study found that the same optical density (OD) has the same test zone band intensity irrespective of AuNP size. This study also illustrates the use of absorption maxima (λ max) techniques to characterize AuNPs and to prevent wastage of protein while developing immunochromatographic test kits.

scholarly journals The synergistic effects of Lactobacillus acidophillus ROO52 and Lactobacillus bulgaricus LB-12 bacteriocins against E.coli O157 :H7 in milk

2014 ◽  
Vol 38 (2) ◽  
pp. 35-40
Author(s):  
Zina Saab Khudhir
Keyword(s):  
Lactobacillus Acidophilus ◽  
Synergistic Effects ◽  
Antimicrobial Effect ◽  
Average Diameter ◽  
Raw Milk ◽  
Inhibition Zone ◽  
Latex Agglutination ◽  
Lactobacillus Bulgaricus ◽  
Milk Samples ◽  
Test Kit

        The aims of this study to evaluate the antibacterial potential of standard strains (Lactobacillus acidophilus ROO52 and Lactobacillus bulgaricus LB-12) that produce bacteriocins against E.coli O157:H7 in raw milk.  Thirty raw milk samples randomly were collected weekly different markets of Baghdad city in order to investigate the prevalence of E.coli O157:H7 in milk. The prevalence of  E.coli O157:H7 in raw milk samples was  6 out 30 (20%) by using the modern chromogenic media with serological latex agglutination test kit. The average diameter of the inhibition zone of crude bacteriocin against  E .coli O157:H7 by using combination of 1:1 (v/v) of the Lactobacillus acidophillus ROO52 and  Lactobacillus bulgaricus LB-12was (14mm) ,while that produced by bacteriocins of Lactobacillus acidophillus ROO52 and  Lactobacillus bulgaricus LB-12  independently were 16 and 12mm respectively .L. delbrucekii ssp bulgaricus showed significantly (P<0.05) low antimicrobial effect against E.coli O157 :H7 .While the strongest antimicrobial effect was shown by Lactobacillus acidophilus ROO52. The bacteriocins of the reference strains used in this study did not result in an increase in inhibition when used in combination of 1:1 (v/v).

scholarly journals Prevalence of canine Parvo virus infection in street dogs using rapid antigen detection Kit

2015 ◽  
Vol 2 (3) ◽  
pp. 459-464
Author(s):  
Faizul Wasima Nahat ◽  
Md Siddiqur Rahman ◽  
Roma Rani Sarker ◽  
Md Kumrul Hassan ◽  
AKM Zeaul Hasan ◽  
...  
Keyword(s):  
Virus Infection ◽  
Infectious Diseases ◽  
Demographic Variables ◽  
Antigen Detection ◽  
Canine Parvovirus ◽  
Test Kit ◽  
Rectal Swabs ◽  
Chisquare Test

Canine parvovirus is one of the most common infectious diseases of dogs. A study was carried out to diagnose the infection of canine parvovirus in street dogs from different places of Mymensingh Town. Rectal samples were collected from January to April, 2015. A total of 114 rectal swabs were collected conveniently from street dogs of Mymensingh. The samples were diagnosed using RapiGEN Canine Parvo Virus Ag Test Kit. The association of CPV infection with demographic variables was assessed by Chisquare test. The overall prevalence of CPV was 32.0% in dogs. The prevalence of parvovirus infection was found to be significantly higher in puppies and 6 months of age (58.3%) than those >24 months of age (p=0.005). The prevalence of canine parvovirus infection also varied significantly in different study area (p=0.003). The prevalence of canine parvovirus infection was higher in male (34.4%) than that in female (30.2%) but it was not statistically significant.Res. Agric., Livest. Fish.2(3): 459-464, December 2015

scholarly journals AVIAN INFLUENZA ANTIBODY RESPONSE IN PIGLETS THATAREGIVEN ESCHERICHIA COLI–AVIAN INFLUENZA VACCINES

2021 ◽  
Vol 10 (1) ◽  
pp. 61-70
Author(s):  
Audrey Febiannya Putri Bhaskara ◽  
I Gusti Ngurah Kade Mahardika ◽  
I Nyoman Suartha
Keyword(s):  
Escherichia Coli ◽  
Avian Influenza ◽  
Optical Density ◽  
Antibody Test ◽  
Influenza Vaccines ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Antibody ◽  
E Coli ◽  
Test Kit ◽  
Virus Influenza

Babi berperan penting dalam ekologi virus influenza, karena babi dapat berperan sebagai wahana untuk reasorsi virus influenza dari unggas dan mamalia. Vaksinasi dengan antigen influenza universal, yaitu nukleoprotein, dapat menurunkan peluang babi dalam memunculkan virus influenza baru. Penelitian ini bertujuan untuk mengentahui respons antibodi dari vaksinasi dengan nukleoprotein rekombinan - Escherichia coli. Sebanyak 12 anak babi landrace dari tiga induk yang berbeda dipilih secara acak. Enam ekor divaksinasi dengan vaksin nucleoprotein-E. coli pada umur tujuh hari dan diulang pada umur 21 hari. Enam ekor tidak divaksinasi. Serum diambil pada umur 35 hari. Nilai optical density (OD) antibodi terhadap nukleoprotein diuji dengan teknik Enzyme-Linked Immunosorbent Assay (ELISA) dengan menggunakan Kit ELISA komersial, Avian Influenza Virus Antibody Test Kit. Hasil penelitian menunjukkan bahwa nilai Optical Density rata-rata babi yang divaksinasi (0,367) secara statistika nyata lebih tinggi dibandingkan dengan yang tidak divaksinasi (0,054). Vaksin rekombinan nucleoprotein-E. coli yang dicobakan mampu meningkatan antibodi terhadap virus avian influenza pada anak babi.

scholarly journals Gold nanoparticle-based lateral flow kit for in vitro detection of malaria antibodies

2018 ◽  
Author(s):  
◽  
Christian Lungani Mthembu
Keyword(s):  
Test Line ◽  
Point Of Care ◽  
Three Dimensional ◽  
Lateral Flow ◽  
Igg Antibody ◽  
Diagnostic Kits ◽  
Test Kit ◽  
Malaria Antigen ◽  
And Performance

This study involves the development of three-dimensional dual lateral flow diagnostic assays. These assays were fabricated with quick response (QR) barcodes to ease the accessibility and transfer test data. The assays were designed to also improve the collection and transfer of survey from point-of-care facilities to centralized laboratories, thus, these would help to speed-up response to disease out-break. The study introduces the fabrication of two barcode based malaria diagnostic in the field of diagnostics. Two lateral flow kits were modified with two QR barcodes and three QR barcodes encoded with Google analytics codes for the detection and real-time tracking of malaria lateral flow which was designed to detect Plasmodium lactate dehydrogenase (pLDH). The fabrication of test kit was achieved by attaching two and three QR barcodes into two different test kits which were encoded with websites that were linked to Google analytics website as a tracking and performance monitor. Gold nanoparticles (AuNPs) were used as a substrate, where optical and structural properties were studied using UV/Visible spectroscopy, fluorescence spectroscopy, and transmission electron microscopy (TEM). The anti-mouse IgG antibody was used as a secondary antibody to act as control and the anti-(pLDH) was stripped on the test line. Phosphate buffer was used as a mobile phase solution. The antibody binding with pLDH antigen showed red test line indicating a positive test. Two diagnostic kits for rapid detection of pLDH were developed and validated for the detection of malaria antigen with lowest detectable recombinant concentration of 10 ng.mL-1. The diagnostic kits were incorporated with two and three optimally angled QR barcodes for identifying positive and negative. The second three QR barcode embedded test kit identified positive, negative and invalid using tracked website. These QR barcodes enabled massive results and tracking with precise location of the test through Google Analytics.

scholarly journals Malaria and HIV sero-positivity: study on selected individuals at a tertiary healthcare centre in Port Harcourt, Nigeria

2019 ◽  
Vol 34 (2) ◽  
Author(s):  
Iheanyi O. Okonko ◽  
Anwuli U. Osadebe ◽  
Eberechukwu M. Okoli ◽  
Ego D. Eke
Keyword(s):  
Malaria Infection ◽  
Health Centre ◽  
Malaria Prevention ◽  
Port Harcourt ◽  
Test Kit ◽  
Malaria Antigen ◽  
Tertiary Healthcare ◽  
Low Incidence ◽  
The Tropics ◽  
Age Range

Over 50% of the global population is vulnerable to malaria infection. An estimated 300 million malaria cases occur annually in the tropics with 90% of these in the sub-Sahara, a region that already suffers the greatest burden of HIV-1 infection. This study assessed the prevalence of HIV and malaria infections in a cohort of 200 undergraduates, consisting of 100 females and 100 males, attending the Health Centre at the University of Port Harcourt, Nigeria. Blood samples were screened for the presence of malaria and HIV, using SD Boline malaria Antigen P.F. test kit and Determine® HIV one step rapid Kit. The overall prevalence for HIV in this study was 2.5% while the overall prevalence of malaria was 1.5%. The prevalence of HIV based on gender was 2.0% and 3 % for females and males, respectively. For malaria, these values were 2.0% and 1.0% for females and males, respectively. No incident of co-infection was recorded in this study. The findings did not indicate any relationship between HIV seropositivity and malaria infection but underscored the low incidence of both malaria and HIV within the 17-26 age range and amongst relatively well-educated individuals. In spite of the low prevalence observed, there is still the need for awareness of HIV and Malaria prevention amongst university students. Further studies could be undertaken to investigate other relevant epidemiology parameters with regards to HIV and malaria in the tropics.

scholarly journals Immunoglobulin G Concentrations in Alpaca Colostrum during the First Four Days after Parturition

Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 167
Author(s):  
Maria Mößler ◽  
Kathrin Rychli ◽  
Volker Reichmann ◽  
Thiemo Albert ◽  
Thomas Wittek
Keyword(s):  
Immune System ◽  
Immunoglobulin G ◽  
Protein Concentration ◽  
Strong Association ◽  
The Other ◽  
Radial Immunodiffusion ◽  
Test Kit

Colostrum provides the newborn with nutrients and immunoglobulins. Immunoglobulins and their intestinal transfer play a major role in the immune system of neonates since they are born agammaglobulinemic. In this study immunoglobulin G (IgG) content was determined in alpaca colostrum and the correlations of the IgG concentration by fat, protein, lactose and minerals were calculated. Colostrum samples were collected daily from 20 multiparous alpaca mares during the first four days after parturition. The IgG concentrations were determined by radial immunodiffusion using a Camelid IgG Test Kit. The IgG concentration decreased significantly from 26,319 mg/dL on day 1 to 3848.8 mg/dL on day 4. There were significant correlations between IgG concentration and the other components of the colostrum. While the correlations between IgG and fat (r = −0.69, p ≤ 0.001) and lactose (r = −0.64, p ≤ 0.001) were negative, the correlations with protein (r = 0.91, p ≤ 0.001), magnesium (r = 0.86, p ≤ 0.001) and cobalt (r = 0.87, p ≤ 0.001) were strongly positive. Due to the strong association, the colostrum protein concentration could be used for a brief estimation of the IgG content.

scholarly journals Cerebrospinal Fluid Analysis in Dogs and Cats with Neurological Diseases

2019 ◽  
Vol 47 (1) ◽  
Author(s):  
Renato Tavares Conceição ◽  
Karina Keller Marques Da Costa Flaiban ◽  
Fernanda Catacci Guimarães ◽  
Mônica Vicky Bahr Arias
Keyword(s):  
Infectious Diseases ◽  
Cell Count ◽  
Laboratory Tests ◽  
Protein Concentration ◽  
Mononuclear Cells ◽  
Neurological Diseases ◽  
Degenerative Diseases ◽  
Presumptive Diagnosis ◽  
Neoplastic Diseases ◽  
Csf Analysis

Background:Cerebrospinal fluid (CSF) analysis is of great importance for evaluation of patients with central nervous system problems, because it helps to confirm or exclude many diseases when evaluated together with other relevant clinical and ancillary laboratory tests. As there are few studies in Brazil describing results of CSF analysis in dogs and cats, the objective of the present study was to evaluate results of CSF analysis in a period of ten years, grouping the changes observed, mainly total and differential cell count and total protein concentration, according to the following etiological categories of diseases: inflammatory, degenerative, traumatic, neoplastic and vascular disorders.Materials, Methods &Results:Medical records of dogs and cats with neurological diseases that had CSF collected and analyzed at a Veterinary Teaching Hospital between 2008 and 2017 were retrospectively reviewed. Patient data included breed, sex, body weight, age at presentation, findings of clinical and neurological examination, results of CSF analysis, diagnostic imaging and other laboratory tests results including PCR and serologies for infectious diseases. A total of 245 CSF exams were studied (240 dogs and five cats). The established normal range for protein concentration was less than 25 mg/dL for cisternal collection and less than 45 mg/dL for lumbar puncture. Total nucleated cell count was considered normal when less than 5 cells/µL, with a predominance of mononuclear cells. Both pleocytosis and increased concentration of the protein level were classified as discrete, moderate and marked, and the pleocytosis was further classified as mononuclear, neutrophilic and mixed cell pleocytosis. The information obtained was analyzed in relation to the neurological syndromes and etiological categories of neurological diseases. The most frequent syndrome was thoracolumbar and the less frequent was cerebellar. Regarding the etiological categories, the most frequent in decreasing order were inflammatory, infectious, degenerative, neoplastic, traumatic, vascular and episodic. CSF examination was abnormal in 72% of cases. In viral infectious diseases, there was predominantly mononuclear pleocytosis with a slight increase of protein, whereas in dogs with presumptive diagnosis of meningoencephalitis of unknown origin (MUO), marked mononuclear and mixed pleocytosis predominated with moderate to marked protein increase. In degenerative diseases, however, the absence of pleocytosis or mild pleocytosis, with normal to slightly increased protein was most observed. In neoplastic diseases there was a high frequency of mild to moderate pleocytosis, with and without albuminocytological dissociation, while in spinal trauma there was mainly mononuclear pleocytosis. A slight increase in protein was observed mainly in infectious, degenerative, neoplastic and traumatic diseases, while moderate to marked increase was more observed in cases of presumptive diagnosis of MUO. Albuminocytological dissociation was observed in half of the cases of neoplasia and less frequently in degenerative, infectious and traumatic diseases.Discussion: The exam was altered in a considerable number of patientsand provided important information even when normal. The diseases with more abnormalities were inflammatory/infectious and neoplastic diseases. When the exam was normal, the most frequent condition was degenerative diseases. Although the changes were not specific for each class of neurological disease, there were certain trends regarding pleocytosis type and protein increase in some of them. Based on the results of this retrospective study, result of CSF analysis, when interpreted along with signalment, etiological categories of diseases, neurological syndromes, and results of other complementary tests, provided support for the diagnosis of various neurological diseases.

scholarly journals Blocking ELISA to Distinguish Pseudorabies Virus-Infected Pigs from Those Vaccinated with a Glycoprotein gIII Deletion Mutant

1990 ◽  
Vol 2 (1) ◽  
pp. 14-23 ◽  
Author(s):  
Saul Kit ◽  
Yukikazu Awaya ◽  
Haruki Otsuka ◽  
Malon Kit
Keyword(s):  
Optical Density ◽  
Deletion Mutant ◽  
Pseudorabies Virus ◽  
Standard Dose ◽  
False Negative ◽  
Elisa Test ◽  
Negative Control ◽  
Enzyme Linked Immunosorbent Assay ◽  
Blocking Elisa ◽  
Test Kit

A blocking enzyme-linked immunosorbent assay (ELISA) test has been developed to distinguish pseudorabies virus (PRV)-infected pigs from those immunized with a glycoprotein g92(gIII) deletion mutant, PRV(dlg92dltk). The blocking ELISA utilizes 96-well microtiter test plates coated with a cloned PRV g92(gIII) antigen, a mouse monoclonal antibody against gIII antigen (moMCAgIII): horseradish peroxidase (HRPO) conjugate, and undiluted test sera. Analyses can be completed in less than 3 hours with results printed out by an automated plate reader. Analyses on over 300 pig sera from PRV-free farms, on sera from other species, and on control sera containing antibodies to microorganisms other than PRV showed that the ratio of the optical density at 405 nm for the test sample to the optical density at 405 nm for the negative control (S/N value) was >0.7 for all sera. No false positives were identified. Likewise, the S/N values were >0.7 for over 400 sera obtained from pigs vaccinated twice with more than 1,000 times the standard PRV (dlg92dltk) dose or 1–4 times with the standard dose (2 × 105 TCID50/pig). Following challenge exposure to virulent PRV, the S/N values of the vaccinates were 0.1, showing that g92(gIII) antibodies in the sera of experimentally challenged pigs strongly blocked the binding of the moMCAgIII: HRPO conjugate to the antigen-coated wells. Sera of 233 pigs from PRV-infected herds with virus neutralization (VN) titers of 1:4 or greater were tested. All except 2 of these sera had S/N values <0.7 and more than 175 had S/N values <0.1. Sixteen sera from feral pigs with VN titers of 1:4 or greater had S/N values of 0.24 or less, but 2 sera with VN titers of 1:4 when tested 5 years prior to the PRV g92(gIII) blocking ELISA test gave false negative S/N values. Twenty-four of 29 pig sera from PRV-infected herds with VN titers < 1:4 were positive for g92(gIII) antibodies, illustrating the sensitivity of the PRV g92(gIII) blocking ELISA test. Analyses on 7 sera with VN titers of 1:4–1:64 showed that titers obtained with the PRV g92(gIII) blocking ELISA test were from 2- to 16-fold greater than the VN titers. The accuracy and sensitivity of the PRV g92(gIII) blocking ELISA test was further demonstrated by analyses of 40 unknown sera supplied in the National Veterinary Services Laboratories 1988 PRV check test kit.

scholarly journals Immunochemical Analytical Methods for the Determination of Peanut Proteins in Foods

2005 ◽  
Vol 88 (1) ◽  
pp. 161-174 ◽  
Author(s):  
Thomas B Whitaker ◽  
Kristina M Williams ◽  
Mary W Trucksess ◽  
Andrew B Slate
Keyword(s):  
Analytical Methods ◽  
Protein Concentration ◽  
The Body ◽  
Peanut Protein ◽  
Water Soluble ◽  
Enzyme Linked Immunosorbent Assay ◽  
Food Matrix ◽  
Test Kit ◽  
Peanut Proteins

Abstract Peanut proteins can cause allergenic reactions that can result in respiratory and circulatory effects in the body sometimes leading to shock and death. The determination of peanut proteins in foods by analytical methods can reduce the risk of serious reactions in the highly sensitized individual by allowing for the detection of these proteins in a food at various stages of the manufacturing process. The method performance of 4 commercially available enzyme-linked immunosorbent assay (ELISA) kits was evaluated for the detection of peanut proteins in milk chocolate, ice cream, cookies, and breakfast cereals: ELISA-TEK Peanut Protein Assay, now known as “Bio-Kit” for peanut proteins, from ELISA Technologies Inc.; Veratox for Peanut Allergens from Neogen Corp.; RIDASCREEN Peanut Kit from R-Biopharm GmbH; and ProLisa from Canadian Food Technology Ltd. The 4 test kits were evaluated for accuracy (recovery) and precision using known concentrations of peanut or peanut proteins in the 4 food matrixes. Two different techniques, incurred and spiked, were used to prepare samples with 4 known concentrations of peanut protein. Defatted peanut flour was added in the incurred samples, and water-soluble peanut proteins were added in the spiked samples. The incurred levels were 0.0, 10, 20, and 100 μg whole peanut per g peanut protein per g food; the spiked levels were 0.0, 5, 10, and 20 μg peanut protein per g food. Performance varied by test kit, protein concentration, and food matrix. The Veratox kit had the best accuracy or lowest percent difference between measured and incurred levels of 15.7% when averaged across all incurred levels and food matrixes. Recoveries associated with the Veratox kit varied from 93 to 115% for all food matrixes except cookies. Recoveries for all kits were about 50% for cookies. The analytical precision, as measured by the variance, increased with an increase in protein concentration. However, the coefficient of variation (CV) was stable across the 4 incurred protein levels and was 7.0% when averaged across the 4 food matrixes and analytical kits. The R-Biopharm test kit had the best precision or a CV of 4.2% when averaged across all incurred levels and food matrixes. Because measured protein values varied by test kit and food matrix, a method was developed to normalize or transform measured protein concentrations to an adjusted protein value that was equal to the known protein concentration. The normalization method adjusts measured protein values to equal the true protein value regardless of the type test kit or type food matrix.

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