scholarly journals Evaluation of designed IS711 primers and universal primers of B4 and B5 for detection of Brucella spp. in clinical samples

2020 ◽  
Author(s):  
Pedram Heidari ◽  
Mitra Salehi ◽  
Abbas Akhavan Sepahi ◽  
Mohamad Reza Razavi
Keyword(s):  
Diagnostic Techniques ◽  
The Other ◽  
Universal Primers ◽  
Molecular Diagnostic ◽  
Clinical Samples ◽  
Molecular Diagnostic Techniques ◽  
Target Sequence ◽  
Molecular Approaches ◽  
Detection And Identification ◽  
Antibody Titers

Abstract Background: Brucellosis as a global concern is a zoonotic infectious disease which affects a large number of individuals in developing countries. Microbiological, serological and molecular approaches are useful for detection and identification of Brucella spp. A confirmed diagnosis requires isolation of Brucella from clinical specimens that is the most sensitive method in the acute and sub-acute phases of the diseases. On the other hand, molecular diagnostic techniques are more sensitive and more specific than serological techniques, especially in chronic localized cases because of antigenic cross-reactions or antibody titers lower than 160. Until now different Brucella specific sequences like BCSP 31, IS711 and 16SrRNA have been amplified for detection of Brucella spp. In this study, the sensitivity and specificity of The B4-B5 primers and IS711 designed primers were evaluated for detection of of Brucella Spp. in the clinical samples. Results : Amplification of extracted DNA from serum of 49 suspected patients were tested with two sets of specific primers. The BCSP31 amplicon was 223 bp and all the 49 (100%) serum specimens were positive by B4-B5 primers, including 4 cases with negative 2ME test result. The designed IS711 primers amplified the IS711 product with 448 bp length and 46 of 49 (93.87%) cases were positive. The sensitivity of the applied primers (B4-B5 and IS711) was evaluated by using the serial dilutions of extracted purified DNA molecules of B. melitensis and B. abortus . The B4-B5 primers can detect the least number of both B. melitensis and B. abortus , 0.1 CFU/reaction. However, the designed IS711 set is able to detect 10 CFU/reaction. The B4-B5 primer and IS711 designed primer recognized 100% (49/49) and 94% (46/49) of the cases, respectively. Conclusion: This study indicated that the sensitivity of B4-B5 primer is 100%, while the sensitivity of the designed primer of IS711 is 94%. The laboratory experiment revealed that designed IS711 set is 1×10 2 times more sensitive than sensitivity of the other experiments for detection of IS711 target sequence in the specimens.

Diagnosis of melioidosis: the role of molecular techniques

2021 ◽  
Vol 16 (4) ◽  
pp. 271-288
Author(s):  
Ian Gassiep ◽  
Delaney Burnard ◽  
Michelle J Bauer ◽  
Robert E Norton ◽  
Patrick N Harris
Keyword(s):  
Laboratory Diagnosis ◽  
Diagnostic Techniques ◽  
Molecular Techniques ◽  
Molecular Diagnostic ◽  
Clinical Samples ◽  
Molecular Diagnostic Techniques ◽  
Detection And Identification ◽  
Life Years ◽  
Culture Independent ◽  
Future Utility

Melioidosis is an emerging infectious disease with an estimated global burden of 4.64 million disability-adjusted life years per year. A major determinant related to poor disease outcomes is delay to diagnosis due to the fact that identification of the causative agent Burkholderia pseudomallei may be challenging. Over the last 25 years, advances in molecular diagnostic techniques have resulted in the potential for rapid and accurate organism detection and identification direct from clinical samples. While these methods are not yet routine in clinical practice, laboratory diagnosis of infectious diseases is transitioning to culture-independent techniques. This review article aims to evaluate molecular methods for melioidosis diagnosis direct from clinical samples and discuss current and future utility and limitations.

scholarly journals Evaluation of designed IS711 primers and universal primers of B4 and B5 for detection of Brucella spp. in clinical samples

2019 ◽  
Author(s):  
Pedram Heidari ◽  
Mitra Salehi ◽  
Abbas Akhavan Sepahi ◽  
Mohamad Reza Razavi
Keyword(s):  
Blood Culture ◽  
Universal Primers ◽  
Clinical Samples ◽  
Target Sequence ◽  
Serum Samples ◽  
Serological Tests ◽  
Molecular Approaches ◽  
Bacterial Agent ◽  
Detection And Identification ◽  
Wide Range

Abstract Background Brucellosis as a global concern is a zoonotic infectious disease which affects a wide range of individual in developing countries. A confirmed diagnosis is required to isolate the bacterial agent from clinical specimens like blood, bone marrow, CSF or tissues. Microbiological, serological and molecular approaches are useful for detection and identification of Brucella spp. and blood culture is known as the gold standard for Brucella spp. Diagnosis of brucellosis through polymerase chain reaction (PCR) could be more sensitive and specific than other classical methods such as blood culture and conventional serological tests. Until now different Brucella specific sequences like BCSP 31, IS711 and 16SrRNAwere amplified for detection of Brucella Spp. Results Amplification of extracted DNA from serum of 49 suspected patients were tested with two sets of specific primers. The BCSP31 sequence amplicon was 223 bp and all the 49 (100%) serum specimens isolated from suspected patients were positive by B4 and B5 primers, even the 4 cases out of 49 2ME negative samples were positive. Detection of Brucella in serum samples by designed IS711 primers revealed the amplicon of IS711 with 448 bp length. Among the 49 serum samples isolated from patients, 46 (93.87%) cases were positive. The B4-B5 primers and IS711 designed primer recognized 100% (49/49) and 94% (46/49) of the cases, respectively. Conclusion This study shows that the specificity of the 2 primer sets is 100% and the sensitivity of B4-B5 primers is 100%, while the sensitivity of the designed primers of IS711 is 94%. The B4-B5 primers can detect the least number of both B. melitensis and B. abortus, 0.05 CFU/reaction. However, the designed IS711 set is able to detect 2 CFU/reaction, about 2.5×102 times more sensitive than results of other experiments for detection of IS711 target sequence in the specimens.

scholarly journals Prevalence of Bacterial Infections and the use of Multiplex Pcr Assay for Rapid Detection in Cultured Fish in Ghana.

2021 ◽  
Author(s):  
Rhoda Lims Diyie ◽  
Dennis W. Aheto ◽  
Mike Y. Osei-Atweneboana ◽  
Emmanuel Armah ◽  
Kobina Yankson
Keyword(s):  
Bacterial Infections ◽  
Molecular Genetic ◽  
Diagnostic Techniques ◽  
Infected Fish ◽  
Molecular Diagnostic ◽  
Clinical Samples ◽  
Molecular Diagnostic Techniques ◽  
Stressed Condition ◽  
Multiplex Pcr Assay ◽  
Cultured Fish

Abstract The modern and rapid avenue for detecting pathogens provided by molecular genetic techniques including polymerase chain reaction (PCR) was explored in the present study to identify prevalent disease pathogens, from six aquaculture farms and in two commonly cultured fish in Ghana. The specific detection was carried out directly on clinical samples of naturally infected fish (O. niloticus and C. gariepinus) based on syber-mix reaction protocol in traditional PCR. Molecular diagnostic techniques allowed the detection of six most common and important bacteria pathogens in aquaculture farms in Ghana. Also, three of the pathogens (Streptococcus agalactiae, Streptococcus iniae and Staphylococcus aureus) were simultaneously isolated in a multiplex reaction. The results indicated 90% - 100% sensitivity and specificity for each of the six bacterial pathogens tested. Streptococcosis and motile aeromonad septicemia were found to be highly prevalent in most aquaculture farms in Ghana with severity in infections traced to the 85.7% and 14.9% co-infections with all six target pathogens in catfish and tilapia respectively. Prevalence rate of infections significantly correlated with variations in salinity, conductivity and dissolved oxygen concentrations in the thermal stressed condition of the culture water.

scholarly journals Molecular diagnostics of infectious diseases

1997 ◽  
Vol 43 (11) ◽  
pp. 2021-2038 ◽  
Author(s):  
Yi-Wei Tang ◽  
Gary W Procop ◽  
David H Persing
Keyword(s):  
Nucleic Acid ◽  
Infectious Diseases ◽  
Direct Detection ◽  
Clinical Chemistry ◽  
Gene Mutations ◽  
Diagnostic Techniques ◽  
Molecular Diagnostic ◽  
Clinical Samples ◽  
Molecular Diagnostic Techniques ◽  
Plasmid Profiling

Abstract Over the past several years, the development and application of molecular diagnostic techniques has initiated a revolution in the diagnosis and monitoring of infectious diseases. Microbial phenotypic characteristics, such as protein, bacteriophage, and chromatographic profiles, as well as biotyping and susceptibility testing, are used in most routine laboratories for identification and differentiation. Nucleic acid techniques, such as plasmid profiling, various methods for generating restriction fragment length polymorphisms, and the polymerase chain reaction (PCR), are making increasing inroads into clinical laboratories. PCR-based systems to detect the etiologic agents of disease directly from clinical samples, without the need for culture, have been useful in rapid detection of unculturable or fastidious microorganisms. Additionally, sequence analysis of amplified microbial DNA allows for identification and better characterization of the pathogen. Subspecies variation, identified by various techniques, has been shown to be important in the prognosis of certain diseases. Other important advances include the determination of viral load and the direct detection of genes or gene mutations responsible for drug resistance. Increased use of automation and user-friendly software makes these technologies more widely available. In all, the detection of infectious agents at the nucleic acid level represents a true synthesis of clinical chemistry and clinical microbiology techniques.

scholarly journals Molecular and Immunological Diagnostic Techniques of Medical Viruses

2020 ◽  
Vol 2020 ◽  
pp. 1-19
Author(s):  
Daniel Hussien Reta ◽  
Tesfaye Sisay Tessema ◽  
Addis Simachew Ashenef ◽  
Adey Feleke Desta ◽  
Wajana Lako Labisso ◽  
...  
Keyword(s):  
Low Income ◽  
Viral Infections ◽  
Diagnostic Techniques ◽  
Diagnostic Methods ◽  
Low Income Countries ◽  
Molecular Diagnostic ◽  
Clinical Samples ◽  
Molecular Diagnostic Techniques ◽  
Global Public Health ◽  
Patient Sample

Viral infections are causing serious problems in human population worldwide. The recent outbreak of coronavirus disease 2019 caused by SARS-CoV-2 is a perfect example how viral infection could pose a great threat to global public health and economic sectors. Therefore, the first step in combating viral pathogens is to get a timely and accurate diagnosis. Early and accurate detection of the viral presence in patient sample is crucial for appropriate treatment, control, and prevention of epidemics. Here, we summarize some of the molecular and immunological diagnostic approaches available for the detection of viral infections of humans. Molecular diagnostic techniques provide rapid viral detection in patient sample. They are also relatively inexpensive and highly sensitive and specific diagnostic methods. Immunological-based techniques have been extensively utilized for the detection and epidemiological studies of human viral infections. They can detect antiviral antibodies or viral antigens in clinical samples. There are several commercially available molecular and immunological diagnostic kits that facilitate the use of these methods in the majority of clinical laboratories worldwide. In developing countries including Ethiopia where most of viral infections are endemic, exposure to improved or new methods is highly limited as these methods are very costly to use and also require technical skills. Since researchers and clinicians in all corners of the globe are working hard, it is hoped that in the near future, they will develop good quality tests that can be accessible in low-income countries.

scholarly journals Moraxella catarrhalis: from Emerging to Established Pathogen

2002 ◽  
Vol 15 (1) ◽  
pp. 125-144 ◽  
Author(s):  
Cees M. Verduin ◽  
Cees Hol ◽  
André Fleer ◽  
Hans van Dijk ◽  
Alex van Belkum
Keyword(s):  
Moraxella Catarrhalis ◽  
Current Knowledge ◽  
Bacterial Species ◽  
Bacterial Pathogen ◽  
Diagnostic Techniques ◽  
Human Infection ◽  
Molecular Diagnostic ◽  
Molecular Diagnostic Techniques ◽  
Pathogenic Potential ◽  
The Past

SUMMARY Moraxella catarrhalis (formerly known as Branhamella catarrhalis) has emerged as a significant bacterial pathogen of humans over the past two decades. During this period, microbiological and molecular diagnostic techniques have been developed and improved for M. catarrhalis, allowing the adequate determination and taxonomic positioning of this pathogen. Over the same period, studies have revealed its involvement in respiratory (e.g., sinusitis, otitis media, bronchitis, and pneumonia) and ocular infections in children and in laryngitis, bronchitis, and pneumonia in adults. The development of (molecular) epidemiological tools has enabled the national and international distribution of M. catarrhalis strains to be established, and has allowed the monitoring of nosocomial infections and the dynamics of carriage. Indeed, such monitoring has revealed an increasing number of Β-lactamase-positive M. catarrhalis isolates (now well above 90%), underscoring the pathogenic potential of this organism. Although a number of putative M. catarrhalis virulence factors have been identified and described in detail, their relationship to actual bacterial adhesion, invasion, complement resistance, etc. (and ultimately their role in infection and immunity), has been established in a only few cases. In the past 10 years, various animal models for the study of M. catarrhalis pathogenicity have been described, although not all of these models are equally suitable for the study of human infection. Techniques involving the molecular manipulation of M. catarrhalis genes and antigens are also advancing our knowledge of the host response to and pathogenesis of this bacterial species in humans, as well as providing insights into possible vaccine candidates. This review aims to outline our current knowledge of M. catarrhalis, an organism that has evolved from an emerging to a well-established human pathogen.

scholarly journals Exploratory and confirmatory molecular approaches to determine genetically modified status in different crops

2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Hanaa Abdel-Sadek Oraby ◽  
Nadia Aboul-Ftooh Aboul-Maaty ◽  
Hayam Ahmad Al-Sharawi
Keyword(s):  
Genetically Modified Organisms ◽  
Genetically Modified ◽  
Melting Curve ◽  
Conventional Polymerase Chain Reaction ◽  
Melting Curve Analysis ◽  
Target Sequence ◽  
Molecular Approaches ◽  
Detection And Identification ◽  
Food And Feed ◽  
Detection And Quantification

Abstract Background One of the parameters required for the assessment of food and feed safety is detection and identification of genetically modified organisms. Legislation in some countries necessitates detection and quantification of modification in food and feed samples. Scientists have raised concern about safety of antibiotic resistance marker (ARM) genes used for transformation of crops intended for human and animal consumption. In the present work two molecular approaches have been adopted: one exploratory; for detection and quantification of ARM genes in tested plant samples and the other confirmatory; to determine the specificity/reliability of the obtained results. Results Results revealed that primers for neomycin phosphotransferase (nptII) and aminoglycoside 3″ adenyl-transferase (aadA) were amplified in the majority of the 36 DNA screened samples. Melting curve analysis using hygromycin phosphotransferase (aphIV) gene as target sequence for the fluorescent-based detection approach was performed to ensure reliability and specificity of this procedure and to confirm results obtained by using conventional polymerase chain reaction (PCR). Quantitative RT-PCR results and validation analysis followed, revealed that all of the tested DNA samples were not violating the European legislation for GMOs labeling (0.9%). Conclusions The results fully demonstrated the reproducibility, sensitivity/specificity of the adopted approaches for detection and quantification of even traces of GMO contents. Applying measurement uncertainty (MU) procedures presented in this work will help decision makers to ensure compliance with International Legislation and Regulations. This in its turn will facilitate and enhance trading with countries having compelling labeling regulations.

Unusual endophytic non-enhancing tumour in the renal pelvis: a diagnostic dilemma

2021 ◽  
Vol 14 (9) ◽  
pp. e245037
Author(s):  
Murali Krishna ◽  
Santosh Kumar ◽  
Kalpesh Mahesh Parmar ◽  
Venkatesh Dhana Sekaran
Keyword(s):  
Renal Cell ◽  
Cell Cancer ◽  
Diagnostic Techniques ◽  
Molecular Diagnostic ◽  
Molecular Diagnostic Techniques ◽  
Imaging Features ◽  
Diagnostic Dilemma ◽  
Upper Tract Urothelial Cancer ◽  
Cell Variant ◽  
Clear Cell Variant

Renal cell cancer (RCC) is incidentally detected on imaging in 50%–60% of cases. Among the RCCs, clear cell variant is most common and classically seen as heterogenous enhancing lesion on CT imaging. Hypoenhancing mass presents a diagnostic dilemma with differential diagnosis being urothelial carcinoma, fat poor angiomyolipoma, oncocytoma or rarer variants of RCC. Such cases require further evaluation in form of urine cytology or newer molecular diagnostic techniques. Here, we present a case of renal mass with minimal enhancement on CT scan and imaging features suggestive of upper tract urothelial cancer. Final histopathology revealed the mass to be chromophobe variant of renal cell carcinoma.

scholarly journals Bacterial and Fungal Endophthalmitis

2017 ◽  
Vol 30 (3) ◽  
pp. 597-613 ◽  
Author(s):  
Marlene L. Durand
Keyword(s):  
Intravitreal Injection ◽  
Systemic Infection ◽  
Visual Outcome ◽  
Diagnostic Techniques ◽  
Medical Emergency ◽  
Molecular Diagnostic ◽  
Endogenous Endophthalmitis ◽  
Molecular Diagnostic Techniques ◽  
Permanent Loss ◽  
Hematogenous Seeding

SUMMARY Endophthalmitis is a severe eye infection that may result in permanent loss of useful vision in the affected eye. Most cases are exogenous and occur as a complication of cataract surgery, an intravitreal injection, or penetrating ocular trauma. Endogenous endophthalmitis results from hematogenous seeding of the eye by bacteria or fungi, but bacteremia or fungemia may be transient and patients may present without symptoms of systemic infection. Nearly all endophthalmitis patients present with decreased vision, and some also have eye pain. Eye examination usually reveals a hypopyon and intraocular inflammation. Diagnosis is clinical, supported by cultures of the vitreous and/or aqueous or by blood cultures in some endogenous cases. Molecular diagnostic techniques have been used in research laboratories for pathogen identification in endophthalmitis and offer the possibility of rapid diagnosis, including in culture-negative cases. Intravitreal injection of antibiotics is the most important component of treatment; some cases also benefit from surgical debridement of the vitreous by a vitrectomy. The visual outcome depends partly on the pathogen: coagulase-negative staphylococcal endophthalmitis has a better prognosis than does streptococcal endophthalmitis, for example. Endophthalmitis is a medical emergency, and prompt diagnosis and treatment are essential for saving vision.

Sign in / Sign up

Export Citation Format

Share Document