Immunochromatographic Technique Research Articles

Comparison between Immunochromatographic Test and Enzyme Linked Immunosorbent Assay in Diagnosis of Helicobacter pylori Infection among Gastritis Patients in Khartoum State-Sudan

Background: The gold standard for the diagnosis of Helicobacter pylori infection requires an endoscopic biopsy of gastric mucosa for histological examination, urease test and culture; however serological tests are useful as a screening test for Helicobacter pylori infection.
 Objective: To compare between Immunochromatographic Test and Enzyme Linked Immunosorbent Assay techniques in detection of Helicobacter pylori immunoglobulin gamma antibodies in serum of patients suffer from gastritis.
 Materials and Methods: 245 patients were screened for Helicobacter pylori infections by rapid urease test. Sera from these patients were tested for anti- Helicobacter pylori immunoglobulin gamma antibodies by Enzyme Linked Immunosorbent Assay and Immunochromatographic Test techniques.
 Results: Of 245 patients tested, Immunochromatographic Test positive/negative 114 (46.5%)/131 (53.5%), whereas Enzyme Linked Immunosorbent Assay positive/negative were 124 (50.6%)/121 (49.4%). Sensitivity/ specificity was 67.4%/74.5% and 90.2%/89.3% for Immunochromatographic Test/Enzyme Linked Immunosorbent Assay positive/negative, respectively. The diagnostic accuracy was 71%/89.7% for Immunochromatographic Test/Enzyme Linked Immunosorbent Assay, respectively.
 Conclusion: The Enzyme Linked Immunosorbent Assay technique was found to be more sensitive, specific and accurate compared to the Immunochromatographic Test while The Immunochromatographic Test is commercially available, inexpensive and easy to perform compared to the Enzyme Linked Immunosorbent Assay.

Thrombocytopenia; Frequency and Association at the Time of Diagnosis in Dengue Fever, Peshawar


 
 
 
 ABSTRACT:
 OBJECTIVES: To determine the frequency of thrombocytopenia in dengue fever at the time of diagnosis and to see its association with age and gender.
 METHODOLOGY: It was a descriptive retrospective study of dengue cases admitted to the Medical Unit of Naseer Teaching Hospital Peshawar during the 2019 outbreak was performed. Only confirmed dengue by serology (IgM) or dengue NS1 (Non-Specific Antigen 1) by Immunochromatographic Technique (ICT) cases were analysed. Complete Blood Count (CBC) was done for all the cases on admission and prevalence of thrombocytopenia on admission was extracted from the records. SPSS version 23 was used to analyse the data and to calculate Odds Ratio of a gender or age group to have thrombocytopenia at the presentation of dengue fever.
 RESULTS: A total of 69 confirmed dengue cases were admitted in Naseer Teaching Hospital in the 2019 outbreak. Out of these 69 cases, 51 (73.9%) were males and 18 (26.1%) were females. The ages of these patients ranged from 10-58 years. Fifty-one (51) patients were more than 20 years of age and eighteen (18) were 20 years or less. Thrombocytopenia (platelet count<150,000×109/L) was present in 57 (82.6%) patients. Patients older than 20 years of age were more likely to have thrombocytopenia at presentation of dengue fever OR=16, (p=0.0003), whereas difference amongst genders in this regard was not statistically significant OR=1.07, (p=0.09).
 CONCLUSION: There is a high frequency of thrombocytopenia (82.6%) in early dengue fever. Patients older than 20 years are more likely to have thrombocytopenia in early dengue fever.
 
 
 
 
 KEYWORDS: Dengue Fever, Acute Febrile Illness, Thrombocytopenia

Fungal Isolates in HIV positive and negative subjects attending Chukwuemeka Odumegwu Ojukwu University Teaching Hospital, Amaku, Awka, Anambra State, Nigeria

Background: Fungal pathogens are the leading cause of severe healthcare-associated infections in immunocompromised patients, especially from low-income countries like Nigeria. Acquired Immunodeficiency Syndrome (AIDS) arising from HIV infection is reputed to be a key in immune suppression globally. Presently, Anambra state is number 5 in HIV prevalence in Nigeria. This study was aimed at screening patients from the Chukwuemeka Odumegwu Ojukwu University Teaching Hospital, for fungal infections. Samples were collected with consideration to gender, age, occupation, education status and clinical presentations. Methods: Sampling was done according to global best practices. Patients’ consent and details were obtained by signing a consent form and filling of questionnaires respectively. Key questionnaire details included sociodemographic and personal details, history of present illness, clinical signs and symptoms. All patients were screened afresh for HIV-1 and HIV-2 using an immuno-chromatographic technique with Determine kit (Alere, Japan) and Stat-pack kit (USA). Specimens screened include Urine, Blood, Oropharyngeal swab, Skin scraping, and Sputum. All samples were labeled, transported and processed within 1-2 hours of collection. Results: A total of 1200 participants (610 males and 590 females) were examined. About 16.5% and 54.41% of the subjects examined were positive for HIV infections and fungal infections respectively. Overall, 233 males (19.41%) and 420 females (35.0%) had fungal infections. Fungal infections were most prevalent in patients between 30-39 years, 17.75%, followed by 40-49 years (15.0%). Infection was least prevalent in patients between 15-29 years at 5.0%. Farmers had the highest prevalence rate of fungal infection, though not significant when compared with those of traders, artisans and public servants (X2 =0.621; df=2; P>0.05). Candida species were the most prevalent fungal pathogen, accounting for 609 (67.1%) followed by Aspergillus spp. 234 (25.8%) and Cryptococcus species 31 (3.4%). Penicillium and Fusarium spp. were the least prevalent pathogens (1.9%). Oropharyngeal candidiasis was the most common fungal infection (49.9%-17.4% HIV negative and 32.46% HIV positive patients); followed by Pneumocystis pneumonia (28.80%-9.50% HIV negative and 19.30% HIV positive patients). Similarly, Cryptococcal meningitis was the least recorded infection at 16.81% (6.43% HIV negative and 10.38% HIV positive patients). Significantly, fungal infections were more prevalent in HIV infected patients (62.14%) compared to HIV negative patients (33.33%). Conclusion: This study has revealed that HIV positive and negative patients are often affected with fungal infections in Anambra State, Nigeria. This may have contributed to impaired immune system in patients and development of AIDS in HIV infected patients. Poor personal hygiene and intimate association with household pets among subjects examined were the suspected sources of infection. Therefore, there is an urgent need for improved surveillance and monitoring of fungal infections in the area and in other Teaching Hospitals in the country as well as treatments of infected subjects.

Seroprevalence and risk factors of Toxoplasma gondii infection in women with recurrent fetal loss from the province of Khyber Pakhtunkhwa, Pakistan.

In women with a bad obstetric history (BOH), infection is an established cause of recurrent fetal loss. A common infecting agent is the protozoan parasite Toxoplasma gondii (T. gondii). The aim of this study was to measure the prevalence of toxoplasmosis in women with recurrent fetal loss from the Khyber Pakhtunkhwa province of Pakistan. The study included 360 females aged 16-40 years, of which 180 had a bad obstetric history (study group) and the other 180 had no such history (control group). Blood serum samples were tested for toxoplasma IgM antibodies by Enzyme Linked Immunosorbent Assay and for toxoplasma IgG antibodies using an Immunochromatographic technique. The overall seroprevalence of toxoplasma infection in study group females was 40.6% and in control group females it was 7.2%. Specifically, IgM prevalence was 12.8% in the study group and 1.1% in the control group. IgG prevalence was 23.9% in the study group and 6.1% in the control group. IgM and IgG combined prevalence was 3.9% in the study group cases. There is a statistically significant association between BOH and seropositivity for T. gondii (p < 0.0001, Chi square test). Various risk factors associated with T. gondii seroprevalence in study and control groups were analyzed. The seroprevalence of toxoplasmosis was significantly higher in women with a bad obstetric history compared to those with no such history. Associated risk factors had no significant effects on the results.

Development of a Gold Immunochromatographic Assay Method Using Candida Biofilm Antigen as a Bioreceptor for Candidiasis in Rats

AbstractThe gold immunochromatography assay (GICA), a new immunochromatography technique, uses a nitrocellulose membrane as a carrier and a colloidal gold-labeled antigen or antibody as a tracer (bioreceptor). This technology has many advantages over other immunoassays, including its simplicity, rapidity, cheapness, and the lack of a requirement for special training or expensive equipment, and it can be used to detect either antigens or antibodies. Therefore, we chose to develop this method for the diagnosis of candidiasis in Indonesia. The objective of the present study was to develop a diagnostic test for Candida albicans in rats using the GICA method. GICA bioreceptors were developed from biofilm antigens isolated from biofim Candida albicans grown on the surface of nitrocellulose membranes. The formation of biofilms was confirmed using scanning electron microscopy. Antigen levels as bioreceptors were optimized by using the immuno dot method. The samples to be analyzed were antibody serum, in the form of blood serum samples from heart mice that have been induced to become candidiasis. To this end, we optimized the antigen and antibody volumes necessary to make this diagnosis. The results show that the optimum concentration of antigen to be used in the test is 2.5 μg/μL and the optimum volume of antibody is 10 μL. The control rats produced a single red stripe on the control line and the candidiasis rat samples produced a double red stripe, with the bottom line being the control line and the upper line the test line. The test chip was successfully used for the diagnosis of candidiasis in rats and given the name “Candiday Kit.”. We anticipate that this test will be suitable for the diagnosis of candidiasis in humans

Viral hepatitis B and C co-infection with Human Immunodeficiency Virus among adult patients attending selected highly active anti-retroviral therapy clinics in Nigeria’s capital

ABSTRACTHepatitis B and C are liver diseases caused by hepatitis B and C viruses, and co-infection in HIV-positive individuals is common, with increased mortality and morbidity. This study determined the seroprevalence of HIV co-infection with the two viruses among patients attending three major hospitals in the Federal Capital Territory, Nigeria. From February to July 2019, 311 sera samples were collected from HIV positive patients and screened for Hepatitis B and C infection. Immunochromatographic and ELISA techniques for HBsAg and HCV were used. Socio-demographic features and responses to risk factors were obtained using questionnaires. Patients’ data and results obtained were analyzed with SPSS version 25. The prevalence of HIV/HBV/HCV, HIV/HBV, and HIV/HCV co-infection were 0.64%, 6.43%, and 3.86%, respectively. The triple infection and both co-infections were preponderant among females than males, with a prevalence rate of 0.64%, 3.85%, 2.57%, and 0%, 2.57%, 1.29%, respectively. People aged 31–40 years had the highest triple infection (0.64%) and HIV/HCV infection rate (2.57%), while patients aged 21–30 years had the highest HBV co-infection (3.22%) rates. Widowed patients had the most co-infection rate in all cases. High-risk behavior indicated that there was a significant association between blood donation/reception and engagement in unprotected sex and HIV/HBV/HCV co-infection. The other risk factors revealed no significant effect (p > .05). There was generally a low rate of exposure to associated risk factors. This study highlighted the endemicity of hepatitis virus co-infection in Abuja and the existence of few reports of HIV co-infection with HBV and HCV compared to the nation’s population.

Blastocystis spp. and Giardia intestinalis co-infection profile in children suffering from acute diarrhea

Giardia intestinalis and Blastocystis spp. are two common zoonotic intestinal parasites responsible for the majority of diarrheic cases, especially in children. The study was planned to determine the impact role of both Giardia and Blastocystis co-infection in children up to 12years old with acute diarrhea in Beni-Suef, Egypt. Also, to estimate the general prevalence rates and risk factors associated with intestinal parasitic infections. Stool samples collected from 125 children, within a period of 7months, were examined using direct wet mount and trichrome stain in comparison to in vitro culture on Jones medium (for detecting Blastocystis spp.) and Immunochromatography techniques (for detecting Giardia). At least one type of intestinal parasites was harbored in 72% of the studied children, single infection constituted 37.6% while, 34.4% were polyparasitized children. The predominant parasites involved were Blastocystis spp.(53.6%), followed by Giardia intestinalis (27.2%). Co-infection between both parasites was recorded in 20% of cases. Two risk factors were significantly associated with higher risk of Giardia-Blastocystis co-infection including age category (5-7years) and family size (≥ 6 members) by univariate analysis (P = 0.004, 0.009 respectively) and also by the multivariate model (OR = 0.526, 0.336). Abdominal pain was the only gastrointestinal manifestation associated with the co-infection using the univariate analysis (P = 0.0427). The present study detects a high prevalence of intestinal parasitic infection; in particular, Giardia-Blastocystis co-infection in diarrheic young children (up to 12years) in Beni-Suef Governorate, Egypt and recommends further subtypes identification of both parasites.

DIAGNOSTIC SIGNIFICANCE OF PROCALCITONIN IN SEPSIS

Background: Sepsis is a global healthcare problem, characterized by whole body inflammation in response to microbial infection, which leads to organ dysfunction. It is a frequent complication in hospitalized patients. Despite the use of available treatment modalities mortality in sepsis remains high, often due to delayed diagnosis and treatment.&#x0D; .Objective: To study the efficacy of procalcitonin as a diagnostic marker for sepsis.&#x0D; Design: This was a cross-sectional study.&#x0D; Duration: One year i.e. from January 2017 to January 2018.&#x0D; Setting: Nimra Institute of Medical Sciences, Vijayawada, Andhra Pradesh, India.&#x0D; Participants: 100 Patients aged above 18 years presenting with acute sepsis to the Department Of Medicine, Nimra Institute of Medical Sciences, Vijayawada, Andhra Pradesh, India.&#x0D; Methods: Sepsis was confirmed clinically and/or by positive blood culture. Serum PCT was assayed semi-quantitatively by rapid immunochromatographic technique (within 2 hours of sample receipt). The patients were classified into groups. PCT and various other relevant factors were measured in all study subjects. PCT levels of less than 0.1 ng/ml were considered negative; all other levels were considered positive. Data were presented in the form of statistical Tables and charts. SPSS software version 20 was used for statistical analysis.&#x0D; Results: PCT proved to be an excellent indicator of sepsis. Serum PCT levels predicts mortality in the present study.&#x0D; Conclusion: The PCT assay was found to be a useful biomarker of sepsis in this study. The assay could be performed and reported rapidly and provided valuable information before availability of culture results. This might assist in avoiding unwarranted antibiotic usage.&#x0D; Keywords: Sepsis, Procalcitonin, Marker, Diagnosis.

Presence of anti-HBc antibodies in antigene negatives HBs blood donors at the central hôpital of Yaounde

Introduction: In Cameroon, blood transfusion safety is a real public health problem. It is one of the African countries where screening for HBsAb is not systematic in blood donors, which can expose the beneficiaries of these donations to possible viral hepatitis B (VHB) infections. Methodology: We carry out a descriptive study at the Yaoundé Central Hospital blood bank during the period from August to October 2018. It was intended to determine the residual risk of transmission of VHB related to the presence of HBcAb in blood donors tested negative to HBsAg. The immunochromatographic technique was used for the detection of total HBcAb in blood donors tested negative for HBsAg, HCV, HIV and TPHA markers. The viral markers, HBsAg, HIV, HCVAb, and TPHA, were tested by ARCHITECT, an apparatus which uses the immunological principle of chemiluminescence. Results: Of the 148 donors registered in the study, we had 129 men and 19 women. We obtained an overall transmission risk of HBV related to the presence of HBcAb of 43.24%. This risk was 47.37% for family donors (p = 0.03999) and 27.3% for volunteers. No significant association was found between the sex of the participants (p = 0.3762), age (p = 0.7403), donor regularity (p = 0.4587) and HBcAb frequency. Concluson: In view of these results, the HBcAb remains very high in the blood donors tested HBsAg negative in Cameroon. To complete this study, we suggest the screening for viral DNA in donors who are tested HBsAg negative and HBcAb positive to eradicate this residual risk of HBV transmission through blood transfusion.

Evaluation of Animal Rabies Surveillance System, Ekiti State, Nigeria, 2012-2017

Evaluation of Animal Rabies Surveillance System, Ekiti State, Nigeria, 2012-2017

Association of HLA-G + 3142G > C gene polymorphism and toll-like receptor-9 serum level in systemic lupus erythematosus patients

BackgroundHuman leukocyte antigen-G (HLA-G) and Toll-like receptor-9 (TLR-9) play a role in the regulation of autoimmune diseases and inflammatory processes. Aim of the studyTo detect the HLA-G + 3142G > C gene polymorphism that associated with the susceptibility to SLE patients and associated with Hepatitis B infection and TLR-9 serum level. Patients and methodsThis study was done on 75 SLE patients and 75 healthy control groups. Genotyping of HLA-G + 3142G > C were detected by PCR and PCR-RFLP methods. In addition to the estimation of Hepatitis B surface (HBs) antigen status by immunochromatography technique and TLR-9 serum level by ELISA technique. ResultsThe HLA-G + 3142G > C gene polymorphism between the SLE patients and controls in CC, CG and GG genotyping (5.33% vs. 45.34%; OR = 0.07; P = 1.0 × 10−8, 21.33% vs. 37.34%; OR = 0.46; P = 0.048, 73.33% vs. 17.33%, OR = 47.45; P = 4.5 × 10−12 respectively). In addition, there was a significant increase frequency of G allele in SLE patients compared to controls (0.84 vs. 0.36). While the C allele showed a significantly decreased frequency in patients compared to controls (0.16 vs. 0.64). The seropositive status of HBs antigen showed no significant difference between the SLE patients' group and controls (OR = 7.3, 95%CI = 0.38–140.81). While the mean of TLR-9 serum level was significantly increased in SLE patients' group compared to the control group (399.9 ± 66.7 pg/ml vs. 122.2 ± 28.5 pg/ml; p ≤ 0.05). ConclusionThe HLA-G + 3142G > C homozygous genotype GG and G allele were more associated with SLE patients. The HBs antigen showed no significant association with SLE patients. While, TLR-9 serum level showed a significant association with SLE development.

ELISA and ICT Techniqes in the detection of anti- Rubella virus Antibodies in Aborted women in Al- Nasiriyah city, Thi-Qar, Iraq

A total of 200 serum samples were collected from Bent Al-Huda hospital in Al -Nasiriyah city, Thi- Qar province, Iraq. These samples were collected from aborted women in different ages and cases to detect of Rubella virus by Enzyme Linked Immuno Sorbent Assay (ELISA) and Immuno chromatography (ICT) techniques. It was founded from the recent study 162 (81%) of serum samples were positive by IgG ELISA, and 105 (52.5%) were positive by IgG with ICT technique. All serum samples. were registered negative results to IgM anti- rubella virus by two techniques. The results of ELISA technique were appeared the higher rate (97.95%) for anti-Rubella virus antibodies was observed in second age group ((21-30)years) and a no significant differences were observed in the seropositivity concerning to age groups(P value:>0.05). In ICT, the higher rate (85.71%) of anti-Rubella virus antibodies was observed in the second group of ages, with the presence of significant among the age groups(P value: 0.05), while 90.9% of seropositivity fetal death cases was resulted with ICT technique, and were founded highly significant differences among the rates of seropositivity against rubella virus(P value:< 0.01). The sensitivity and specificity were registered 95% and 61% respectively with ELISA test, while the lower sensitivity and sensitivity values were with ICT test, they were 85% and 57% respectively, and the statistical analysis was appeared the existence of significant differences (P value:< 0.05) between the two tests.

Frequency distribution and risk factors of hepatitis B virus and hepatitis C virus infections among thalassemia patients: a regional study.

Thalassemia is a group of inherited hematological disorders caused by mutation in globin's genes. Regular blood transfusion lengthens the life of thalassemia patients but it carries a definite risk of the infections of blood-borne diseases. The current study was carried out for the frequency distributions and risk factors of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among thalassemia patients in Hazara regions, Pakistan. A total of 324 enrolled thalassemia major patients were diagnosed in five different centers of Hazara regions. The study participants were screened for HBV and HCV using the immunochromatographic techniques test and real-time PCR for immunochromatographic technique-positive specimens. Out of the 324 major thalassemia patients, 24 (7.41%) were diagnosed with HBV and HCV infections. In total, 206 were male patients and the rate of HBV and HCV infections was 0.97% (two patients) and 3.88% (eight patients), respectively. Similarly, 118 were female patients and the rate of HBV-positive patients was 3.39% (four patients) and HCV was 8.47% (10 patients). The results also showed that 50% of HBV and HCV infections were found in the age group of 26-30 years, while 1.81% was found in the age group of 11-15 years. The positive HBV and HCV samples were also verified with the band size of 242 and 227 bp, respectively. Thus, to reduce the incidence of HBV and HCV in thalassemia patients, we must call for critical look on the transfusion practices as well as adoption of stricter donor selection.

New insights into the detection and molecular characterization of Cryptosporidium with emphasis in Brazilian studies: a review.

ABSTRACTCryptosporidium spp. is a pathogenic protozoan present in the gastrointestinal tract of several hosts. This protozoan was originally classified as within the Coccidia Class and has recently been reclassified to gregarine based on studies that observed the evolutionary phases from the process of excision and sequencing of the 18S rRNA gene. Molecular biology techniques have become diagnostic tools and have also been used to understand the epidemiology of Cryptosporidium spp., since several species of this genus are very similar morphologically and morphometrically. Molecular techniques have been used in the identification of parasites, at the species and subtypes levels and to study disease transmission. The laboratory diagnosis of human cryptosporidiosis can be made by parasite detection methods, such as optical microscopy, antigens or genetic material detection, as well as serum antibodies raised to Cryptosporidium spp. Molecular methods were developed and allowed, not only an extensive revision of the taxonomy, but also an improvement in the laboratory diagnosis. In Brazil, there are few reports of Cryptosporidium spp. outbreaks in humans and all of them took place in nurseries. A few epidemiological studies developed in Brazil have used molecular methods for the detection of Cryptosporidium spp., as well as genotyping studies of their species and subtypes. The use of real-time PCR, together with microscopy and immunochromatography techniques, would result in a more precise diagnosis of cryptosporidiosis. The analysis of genotypes, subtypes and clonality of Cryptosporidium could be useful to understand and define the prognosis and severity of infections.

Seroepidemiology of hepatitis B virus among human immunodeficiency virus-infected patients in a tertiary hospital in Nigeria

Aim: This study was aimed at determining the prevalence and associated risk factors for hepatitis B virus (HBV) infection among human immunodeficiency virus (HIV)-infected patients in a tertiary teaching hospital in Nigeria. Patients and Methods: Venous blood was collected from a total of 1680 (comprising of 1177 HIV infected and 503 non-HIV infected) patients and tested for the presence of HbsAg using immunochromatographic technique. Results: The seroprevalence of HBV among HIV and non-HIV-infected patients was 3.8% and 3.6%, respectively. HIV was not identified as a risk factor for HBV seropositivity (P = 0.919). A statistically significant association was found to exist between CD4 count

Prevalence rates of HIV, HBsAg and HCV co-infections among tuberculosis patients in Sokoto Metropolis, Northwest Nigeria

Introduction and Objectives: Tuberculosis (TB) and viral hepatitis are global health problems which are common in developing and undeveloped countries. The current study was aimed at determining the prevalence and co-infections of HIV, HBsAg and HCV among patients with tuberculosis in Sokoto, Northwest Nigeria. Methods: A cross-sectional study was conducted on a total of 276 patients with tuberculosis, aged 19-60 years at Usmanu Danfodiyo University Teaching Hospital, Sokoto and Specialist Hospital, Sokoto between May and November 2015. Blood samples collected were screened for HIV, HBsAg and HCV using immunochromatographic techniques. Results: The prevalence rates of HIV, HBsAg and HCV among TB patients were 16.3%, 14.9% and 5.4%, respectively while the prevalence of co-infections HIV-HBsAg, HIV-HCV, HBsAg-HCV and HIV-HBsAg-HCV in TB patients were 50.7%, 1.81%, 2.9% and 1.45%, respectively. Prevalence of HIV and HCV showed no relationship with age (P=0.240 and 0.987, respectively) but prevalence of HBsAg was associated with age (P=0.0304). There were no relationships of frequencies of HIV, HBsAg and HCV with gender. Conclusion and Recommendations: The study showed high prevalence rates of HIV, HBsAg and HIV-HBsAg co-infections among patients with tuberculosis in Sokoto, while age and gender showed little or no association. HIV and HBsAg tests are recommended for every patient diagnosed with tuberculosis to guide therapeutic decisions.

Development of a lateral flow immunoassay of C-reactive protein detection based on red fluorescent nanoparticles

We have developed a reliable and rapid immunoassay based on a facile synthesis of fluorescent nanoparticles integrated in immunochromatography technique to quantitatively detect C-reactive protein (CRP). The method is based on a sandwich immunoassay using the Nile-red doped nanoparticles/CRP monoclonal antibody conjugate. The method is simple and fast, with a detection limit of 0.091 mg/L. It provides quantitative analysis in the range of 0.1–160 mg/L, which is adequate for detecting CRP of acute inflammatory or cardiovascular disease. This strategy displayed a good reproducibility and stability to straightforwardly analyze the plasma samples without complicated washing steps, thereby reducing the operating procedures for non-professionals and promoting the detection efficiency and the whole detection process can be completed in 3 min. This approach for carrying out immunoassays can be applied to the detection of CRP in the point-of-care tests.

Establishment of time-resolved fluorescence immunochromatographic assay for detection of carbohydrate antigen 19-9

To establish a time-resolved fluorescence immunochromatographic assay for quantitative determination of carbohydrate antigen 19-9 (CA19-9) in serum, we prepared CA19-9 test strips by integrating double-antibody sandwich method and fluorescence immunochromatography technique. Carboxy fluorescent microspheres and nitrocellulose membrane were used as carriers for labeling and coating CA19-9 pairing antibodies. We optimized the process by adjusting the amount of labeling and coating antibody. According to the linear range, lowest detection limit and precision, We evaluated the time-resolved fluorescence immunochromatographic assay of CA19-9. When the amount of labeled antibody was 80 μg for 20 μL fluorescent microspheres, and the concentration of coated antibody on the test line was 1.5 mg/mL, the optimal reaction time was 15 minutes. Assay linear range was 12.5 to 800 U/mL and the minimum detection limit was 6.32 U/mL. The Within-run and between-run coefficient of variation were less than 15%. Average recovery rate was 101%. By detecting 50 clinical samples in parallel with Roche electrochemical luminescence detection kit, correlation coefficient was 0.980 6. The experiment, initially established a fluorescence immunochromatographic detection method to quantitative detection of serum CA19-9, which has a good clinical application prospect.

Rapid and Sensitive Detection of Cardiac Troponin I for Point-of-Care Tests Based on Red Fluorescent Microspheres.

A reliable lateral flow immunoassay (LFIA) based on a facile one-step synthesis of single microspheres in combining with immunochromatography technique was developed to establish a new point-of-care test (POCT) for the rapid and early detection of cardiac troponin I (cTnI), a kind of cardiac specific biomarker for acute myocardial infarction (AMI). The double layered microspheres with clear core-shell structures were produced using soap-free emulsion polymerization method with inexpensive compounds (styrene and acrylic acid). The synthetic process was simple, rapid and easy to control due to one-step synthesis without any complicated procedures. The microspheres are nanostructure with high surface area, which have numerous carboxyl groups on the out layer, resulting in high-efficiency coupling between the carrier and antibody via amide bond. Meanwhile, the red fluorescent dye, Nile-red (NR), was wrapped inside the microspheres to improve its stability, as well to reduce the background noise, because of its higher emission wavelength than interference from real plasma samples. The core-shell structures provided different functional areas to separate antibody and dyes, so the immunoassay has highly sensitive, wide working curves in the range of 0–40 ng/mL, low limits of detection (LOD) at 0.016 ng/mL, and limits of quantification (LOQ) at 0.087 ng/mL with coefficient of variations (CV) of 10%. This strategy suggested an outstanding platform for LFIA, with good reproducibility and stability to straightforwardly analyze the plasma samples without washing steps, thereby reducing the operating procedures for non-professionals and promoting detection efficiency. The whole detection process can be completed in less than 15 min. This novel immunoassay offers a reliable and favorable analytical result by detecting the real samples, indicating that it holds great potential as a new alternative for biomolecule detection in complex samples, for the early detection of cardiac specific biomarkers.

Hematological and serum biochemical alterations in White Fulani cattle with tuberculous lesions

This study assessed hematological and serum biochemical alterations associated with the occurrence of tuberculous lesions in slaughtered White Fulani cattle at Nsukka abattoir, Enugu State, Nigeria. Diagnosis was confirmed by the immunochromatographic technique and histopathology. Out of 567 cattle examined, ten (1.76%) had tuberculous lesions. The tuberculous cattle had normocytic normochromic anemia, leukocytosis, lymphocytosis, eosinophilia and an increased erythrocyte sedimentation rate. They also had significantly lower (p &lt; 0.05) serum alanine aminotransferase, albumin and urea, and significantly higher (p &lt; 0.05) serum globulin than the apparently healthy control animals. We concluded that the occurrence of tubercles in cattle was associated with alterations in hematological and serum biochemical parameters, which may be relevant to the establishment of an antemortem diagnosis of tuberculosis.