Search bioRxiv⌕ Search

Biology subjects

Abidi, S. H.

Publications and source records attributed to Abidi, S. H..

4 recordsLinked to original sources

Clinical and Molecular Characterization of Glioma Patients: miR-21 Expression as a Prognostic Biomarker in Tissue and Serum

BackgroundGlioma remains challenging due to high recurrence rates and resistance to treatment. Diagnosis and follow-up in resource-constrained regions often leads to significant patient attrition. Serum microRNA (miRNA) expression profiles, which have been shown to correlate with tissue expression profiles, are detectable in peripheral blood samples, providing a promising avenue for non-invasive and repeatable liquid biopsies. miR-21 shows promise in many populations; however, there is a dearth of data from our region. MethodologyWe collected 90 tumor tissues, 42 pre- and post-operative serum samples from glioma patients, and included 10 normal tissue adjacent to the tumor (NATs) along with serum samples from 8 healthy individuals and analyzed for miR-21 expression through RT-qPCR. Shapiro Wilk test was applied to calculate data distribution, ANOVA, Fishers exact, and Wilcox test, along with pairwise Students t-test, were applied to determine the differences in gene expression. The expression level of miR-21 was assessed for correlation with Kaplan-Meier survival curves and different molecular markers (IDH, Ki-67, ATRX and p53). The quantitative hazard ratio was determined using Cox regression analysis. ResultsmiR-21 expression in tissue increased with the mean log fold expression 0.101 (median fold = 2.35) in grade 2, 1.00 (median fold = 7.49) in grade 3 and 1.53 (median fold = 26.0) in grade 4 for glioma patients. The expression level showed significant difference between control tissue and grade 4 patients along with significant inter-comparison between grade 1 and grade 4, as well as grade 2 and grade 4.A significant elevated expression of miR-21 has been noticed in patients above 50 years of age. Similarly, in serum samples a significant decline in miR-21 expression was observed in post-operative samples as compared to pre-operative samples mean log fold in grade 2 is 1.30 (11.6-fold), grade 3 is 1.08 (15.3-fold) and grade 4 is 0.749 (13.2-fold). Furthermore, there was positive correlation of miR-21 expression with tumor volume. IDH-wildtype and high Ki-67 expression in gliomas showed significant upregulation of miR-21 compared to IDH-mutant and low Ki-67 respectively. Patients with low miR-21 expression had significantly longer overall survival (OS) than patients with high miR-21 expression. Quantitative hazard analysis indicates that patients in the high expression group have a 3.4 times higher risk of mortality (95% CI: 1.6-7.1), in comparison to patients in the low expression group with AUC of 0.742 (all p <0.05). ConclusionThis study demonstrates the potential of microRNA 21 as a serum biomarker for early, cost-effective diagnosis of glioma. Furthermore, it may inform the development of targeted treatment strategies for various glioma grades, particularly in our population.

molecular biology↗

Analysis of differential expression of matrix metalloproteins and defensins in the nasopharyngeal milieu of mild and severe COVID-19 cases

IntroductionA subset of COVID-19 disease patients suffers a severe form of the illness, however, underlying early pathophysiological mechanisms associated with the severe form of COVID-19 disease remain to be fully understood. Several studies showed the association of COVID-19 disease severity with the changes in the expression profile of various matrix metalloproteinases (MMPs) and defensins. However, the link between the changes in the expression of matrix metalloproteinase (MMPs) and defensins (DA) in the nasopharyngeal milieu, during early phases of infection, and disease severity remains poorly understood. Therefore, we performed differential gene expression analysis of matrix metalloproteinases (MMPs) and defensins in the nasopharyngeal swab samples collected from mild and severe COVID-19 cases within three days of infection and examined the association between MMP and DA expression and disease severity. Material and MethodA total of 118 previously collected nasopharyngeal samples from mild and severe COVID-19 patients (as per the WHO criteria) were used in this study. To determine the viral loads and assess the mRNA expression of matrix metalloproteinase (MMPs) and defensins, a real-time qPCR assay was used. To assess statistically significant differences in the mean expression of viral loads and the cytokines in between the severe and mild groups, an unpaired T-test was applied. The Pearson correlation test was used to assess the correlation between cytokine expressions. In addition, a multivariable logistic regression analysis was carried out with all the variables from the data set using severity as the outcome variable. ResultsOur results showed that the expression of DA3 and MMP2 to be considerably lower in the severe group than in the mild group. Furthermore, there was a significant association between MMP1 and DA4 and DA6 (r=0.5, p=0.0001); as well as between MMP7 and DA1 and DA6 (r=0.5, p=0.00). Additionally, the regression analysis shows a significant correlation (p 0.05) between MMP2 and the severity of COVID-19 disease. ConclusionThe early detection of changes in the expression of MMPs and defensins may act as a useful biomarker/predictor for possible severe COVID-19 disease, which may be useful in the clinical management of patients to reduce COVID-19-associated morbidity and mortality.

microbiology↗

Low-cost and highly efficient: A method for high-quality nucleic acid isolation from cotton fibres

Gene expression analyses to study the development of cotton fibers require high-quality nucleic acid. The conventional methods of nucleic acid extraction results in sub-quality nucleic acids with low yields. Young fibers are rich in polyphenols and sugars that react with nucleic acid to form phenols and insoluble substances. Furthermore, mature fibers contain more than 95% cellulose, hindering the nucleic acid isolation. Cytoplasm collapse and cellulose deposition also result in a very low yield of nucleic acid. Three different methods of RNA isolation from different cotton tissues were compared in this study to determine the best and most efficient one. The integrity and quality of RNA were analyzed using UV spectrum, agarose gel electrophoresis, RIN values, PCR, and Northern blot hybridization. RNA of functional quality was observed when using the high ion and pH method, with an A260/A280 ratio up to 1.87 and an average yield of 0.68 mg g-1 from fiber cells. From leaves, we found an A260/A280 ratio of 2.02 and an average yield of 6.35 mg g-1, which is suitable for molecular biology experiments. The extraction buffer with a high ion density and pH value include Tris-HCl, LiCl, EDTA, SDS, sodium deoxycholate, Nonident P-40, mercaptoethanol, and PVP. The addition of sodium deoxycholate and Nonider-40 (NP-40) enhances the density of other salt compounds and elevates the pH value. The results depicted that the high ion and pH method is a simple and effective way to extract a copious amount of high-quality RNA from polysaccharide-rich tissues. This method is also suitable for the extraction of cotton genomic DNA with high purity. Genomic DNA extracted from cotton using this method showed an A260/A230 ratio up to 2.09 and a yield of 1.44 mg g-1. This method is useful for isolating DNA and RNA from cotton fibers and produces high yields and quality at a comparatively low cost.

genomics↗

SARS-CoV-2 genome analysis of strains in Pakistan reveals GH, S and L clade strains at the start of the pandemic

ObjectivesPakistan has a high infectious disease burden with about 265,000 reported cases of COVID-19. We investigated the genomic diversity of SARS-CoV-2 strains and present the first data on viruses circulating in the country. MethodsWe performed whole-genome sequencing and data analysis of SARS-CoV-2 eleven strains isolated in March and May. ResultsStrains from travelers clustered with those from China, Saudi Arabia, India, USA and Australia. Five of eight SARS-CoV-2 strains were GH clade with Spike glycoprotein D614G, Ns3 gene Q57H, and RNA dependent RNA polymerase (RdRp) P4715L mutations. Two were S (ORF8 L84S and N S202N) and three were L clade and one was an I clade strain. One GH and one L strain each displayed Orf1ab L3606F indicating further evolutionary transitions. ConclusionsThis data reveals SARS-CoV-2 strains of L, G, S and I have been circulating in Pakistan from March, at the start of the pandemic. It indicates viral diversity regarding infection in this populous region. Continuing molecular genomic surveillance of SARS-CoV-2 in the context of disease severity will be important to understand virus transmission patterns and host related determinants of COVID-19 in Pakistan.

genomics↗