PCR Based Detection of Phase Variable Genes in Pakistani Based Clinical Helicobacter pylori Strains

Abstract

BackgroundThe distribution pattern of phase-variable genes varies from strain to strain and from region to region. The present study was carried out to investigate the distribution pattern of phase-variable genes within Pakistan-based Helicobacter pylori strains and to analyze and compare them with strains prevalent in other parts of the world.ObjectivesTo determine the distribution pattern of phase-variable genes in H. pylori strains circulating in Pakistan.Patients and MethodsBiopsy samples were collected from 85 symptomatic patients suffering from various upper gastrointestinal tract symptoms. The biopsy specimens were chopped, then inoculated on H. pylori-specific media and incubated in a Campylobacter Gas Generating kit. Positive isolates were further confirmed via staining and biochemical procedures. Primers were designed for five phase-variable genes using OligoCalc, an oligonucleotide properties calculator (version 3.26) according to parameters stipulated in the literature. Polymerase chain reaction (PCR) was performed on all positive isolates to determine the presence or absence of phase-variable genes.ResultsOn culturing, the prevalence of H. pylori infections in the samples was 44.7%. The prevalence was higher in females than in males, and it increased with age. PCR amplification revealed that the hsdR gene was present in 79% of samples, while the mod and β-subunit genes were present in 16% and 30% of samples, respectively. The streptococcal M protein gene was found in 79%, while the fliP gene was prevalent in 56%.ConclusionsThe distribution patterns of phase-variable genes in Pakistani H. pylori strains were found to be somewhat different. The dominant prevalence of the hsdR gene was an interesting finding, considering its role in bacterial defense in both micro- and macroenvironments.

Framework of Public Agency Website Quality Evaluation in the UAE

“…The findings show that website quality has a strong and significant effect on perceived service quality. This finding confirms the findings of (Ahmad et al, 2016) where the website quality affects website visitors' perception of service quality in the e-commerce setting. Similarly, the findings agree with the findings of (Khalil, 2017) who found that website quality influences users' perception of service quality offered by an organization.…”

“…The results confirmed that perceived quality of the five design elements are indeed influential on users' perceived aesthetics; they have also shown that perceived aesthetics of a website has a significant impact on users' perception of its utility. Ahmad et al (2016) empirically analyzed the critical factors that determine perceptions of the service quality of online shopping sites by using a 25-item eTailQ scale instrument developed by (Wolfinbarger and Gilly, 2003) based on a five-point Likert scale to obtain the perception of a sample of students enrolled in a government-funded central university of India offering post-doctoral programs for undergraduates. The data were analysed using t-test, reliability analysis and EFA.…”

Diagnosis ofHelicobacter pyloriUsing Invasive and Noninvasive Approaches

“…For example, there are more than twenty commercial kits for DNA extraction (i.e., Yekta Tajhiz Azma, Bioneer, Sina-clon, Qiagen, and Sigma) with large variety of the DNA yields which confuse researchers in selecting the proper product. Due to the presence of H. pylori DNA in various biologic samples, PCR-based detection was widely used to identify this problematic infection [ 140 – 143 ]. Biopsy samples, saliva and gastric juice, stool, and dental plaques were frequently applied to PCR detection.…”

Excited State and Reactive Oxygen Species against Cancer and Pathogens: A Review on Sonodynamic and Sono‐Photodynamic Therapy

“…First, modern PDT is safe, minimally invasive, cheap, universal, effective even after a single application, can be combined with pharmacotherapy, and does not induce bacterial resistance or drug resistance. SDT is younger, but also getting attention [4,10,99–101] . Both treatments, as already mentioned, show important common elements.…”