Involvement of 2-deoxyglucose-6-phosphate phosphatases in facilitating resilience against ionic and osmotic stress in Saccharomyces cerevisiae.

The Saccharomyces cerevisiae DOG genes, DOG1 and DOG2, encode for 2-deoxyglucose-6-phosphate phosphatases. These enzymes of the haloacid dehalogenase superfamily are known to utilize the non-natural 2-deoxyglucose-6-phosphate as their substrate. However, their physiological substrate and hence their biological role remain elusive. In this study, we investigated their potential role as enzymes in biosynthesizing glycerol through an alternative pathway, which involves the dephosphorylation of dihydroxyacetone phosphate into dihydroxyacetone, as opposed to the classical pathway which utilizes glycerol 3-phosphate. Overexpression of DOG1 or DOG2 rescued the osmotic and ionic stress-sensitive phenotype of gpp1∆ gpp2∆ or gpd1∆ gpd2∆ mutants, both affected in the production of glycerol. While small amounts of glycerol were observed in the DOG overexpression strains in the gpp1∆ gpp2∆ background, no glycerol was detected in the gpd1∆ gpd2∆ mutant background. This indicates that overexpression of the DOG enzymes can rescue the osmosensitive phenotype of the gpd1∆ gpd2∆ mutant independent of glycerol production. We also did not observe a drop in glycerol levels in the gpp1∆ gpp2∆ dog1∆ dog2∆ as compared to the gpp1∆ gpp2∆ mutant, indicating that the Dog enzymes are not involved in glycerol biosynthesis. This indicates that Dog enzymes have a distinct substrate and their function within the cell remains undiscovered. IMPORTANCE: Yeast stress tolerance is an important characteristic that is studied widely, not only regarding its fundamental insights but also for its applications within the biotechnological industry. Here, we investigated the function of two phosphatase encoding genes, DOG1 and DOG2, which are induced as part of the general stress response pathway, but their natural substrate in the cells remains unclear. They are known to dephosphorylate the non-natural substrate 2-deoxyglucose-6-phosphate. Here, we show that overexpression of these genes overcomes the osmosensitive phenotype of mutants that are unable to produce glycerol. However, in these overexpression strains, very little glycerol is produced indicating that the Dog enzymes do not seem to be involved in a previously predicted alternative pathway for glycerol production. Our work shows that overexpression of the DOG genes may improve osmotic and ionic stress tolerance in yeast.

Transcriptomic meta-analysis to identify potential antifungal targets in Candida albicans.

BACKGROUND: Candida albicans is a fungal pathogen causing human infections. Here we investigated differential gene expression patterns and functional enrichment in C. albicans strains grown under different conditions. METHODS: A systematic GEO database search identified 239 "Candida albicans" datasets, of which 14 were selected after rigorous criteria application. Retrieval of raw sequencing data from the ENA database was accompanied by essential metadata extraction from dataset descriptions and original articles. Pre-processing via the tailored nf-core pipeline for C. albicans involved alignment, gene/transcript quantification, and diverse quality control measures. Quality assessment via PCA and DESeq2 identified significant genes (FDR < = 0.05, log2-fold change > = 1 or <= -1), while topGO conducted GO term enrichment analysis. Exclusions were made based on data quality and strain relevance, resulting in the selection of seven datasets from the SC5314 strain background for in-depth investigation. RESULTS: The meta-analysis of seven selected studies unveiled a substantial number of genes exhibiting significant up-regulation (24,689) and down-regulation (18,074). These differentially expressed genes were further categorized into 2,497 significantly up-regulated and 2,573 significantly down-regulated Gene Ontology (GO) IDs. GO term enrichment analysis clustered these terms into distinct groups, providing insights into the functional implications. Three target gene lists were compiled based on previous studies, focusing on central metabolism, ion homeostasis, and pathogenicity. Frequency analysis revealed genes with higher occurrence within the identified GO clusters, suggesting their potential as antifungal targets. Notably, the genes TPS2, TPS1, RIM21, PRA1, SAP4, and SAP6 exhibited higher frequencies within the clusters. Through frequency analysis within the GO clusters, several key genes emerged as potential targets for antifungal therapies. These include RSP5, GLC7, SOD2, SOD5, SOD1, SOD6, SOD4, SOD3, and RIM101 which exhibited higher occurrence within the identified clusters. CONCLUSION: This comprehensive study significantly advances our understanding of the dynamic nature of gene expression in C. albicans. The identification of genes with enhanced potential as antifungal drug targets underpins their value for future interventions. The highlighted genes, including TPS2, TPS1, RIM21, PRA1, SAP4, SAP6, RSP5, GLC7, SOD2, SOD5, SOD1, SOD6, SOD4, SOD3, and RIM101, hold promise for the development of targeted antifungal therapies.

Pregnancy outcome of anti-HCV direct-acting antivirals: Real-life data from an Egyptian cohort.

We aimed to assess the pregnancy outcome in women with chronic HCV who had negative pregnancy test prior to the anti-HCV course and had unintended pregnancy while on HCV treatment. Hundred patients with a mean age of 30 ± 6.7 y were included and advised to withhold antivirals and continue follow-up in viral hepatitis and obstetrics centres till delivery. All patients received a 12-weeks regimen of anti-HCV [sofosbuvir plus daclatasvir (SOF/DCV): n = 95, SOF/DCV plus ribavirin: n = 3, and paritaprevir/ritonavir/ombitasvir plus ribavirin: n = 2]. Only nine patients completed the full antiviral course against medical advice, and 91 stopped between on-treatment weeks 4 and 8. Eighty-eight patients delivered full-term babies, eight had preterm babies and two had abortions. Of the nine patients who completed the full course of DAAs, seven (77.8%) delivered normal babies, attended their post-treatment week 12 visit, and all (100%) achieved sustained virological response. No major antiviral-related adverse events were reported.

Characteristics and outcome of primary Budd-Chiari syndrome due to Behçet's syndrome.

BACKGROUND AND AIM: Behçet's syndrome (BS) is a known cause of Budd-Chiari syndrome (BCS). We aimed at identifying the prevalence of BS in patients with BCS, analyzing different clinical presentations, treatment modalities and outcome of these patients. METHODS: We conducted a retrospective cohort study, in which all medical records of patients who were presented to Tropical Medicine Department, Ain Shams University with a confirmed diagnosis of primary BCS from May 2005 to December 2016 were collected and analyzed. RESULTS: In total, 271 patients had a confirmed diagnosis of primary BCS, included Group I: 232 (85.6%) patients with BCS without BS and Group II: 39 patients (14.4%) with BCS due to BS. Male gender (P=0.000), oral ulcers, genital ulcers, Prominent abdominal veins, lower limb swellings, lower extremity deep venous thrombosis (P=0.000) and jaundice (P=0.003) were more frequent in group II patients. The presence of intrahepatic collaterals (P=0.004) and IVC thrombosis (P=0.000) was significant in group II. Medical treatment alone in the form of immunosuppressive drugs and anticoagulation (66.7% vs. 24.1%)±IVC stenting (23% vs. 1.3%) (P=0.000) were the main treatment modalities for BCS related to BS. The frequency of HCC in BS was significantly higher (10.26% vs. 2.59%) (P=0.013). CONCLUSIONS: The prevalence of BS in Egyptian patients with BCS is considerably high. The clinical presentation of these patients was different from those without BS. Besides, the incidence of HCC was higher in patients with BS, whereas the mortality did not differ between the two groups.

Circulating microRNA-155 is associated with insulin resistance in chronic hepatitis C patients.

BACKGROUND AND STUDY AIM: Hepatitis C represents a potential public health problem worldwide. Insulin resistance (IR) and type 2 diabetes (T2D) are among the serious metabolic complications for chronic hepatitis C virus (HCV) infection. MicroRNAs (miRNAs) are a group of small non-coding RNAs which are implicated in the modulation of almost all biological processes. The objective of this study was to investigate the levels of both miR-155 and miR-34a in sera of chronic HCV patients with or without T2D. PATIENTS AND METHODS: In this study, we investigated the expression of both miR-155 and miR-34a in 80 subjects (20 HCV, 19 HCV/T2D, 21 T2D and 19 healthy controls), using quantitative real-time PCR. RESULTS: Our results revealed significantly higher levels of both miR-155 and miR-34a in chronic HCV patients compared to healthy control subjects. However, only circulating miR-155 levels showed significant decline in diabetic HCV patients compared to non-diabetic HCV group. Intriguingly, the circulating levels of miR-155 were inversely correlated with HOMA-IR, fasting blood glucose and HbA1c levels. CONCLUSION: Our findings indicate that the insulin resistance and T2D in HCV are strongly related to miR-155. This may suggest a role for miR-155 in the pathogenesis of IR caused by HCV. However, further large-scale studies are required to confirm our findings.

Characteristics of hepatocellular carcinoma in Egyptian patients with primary Budd-Chiari syndrome.

BACKGROUND & AIM: Budd-Chiari syndrome (BCS) is caused by hepatic venous outflow obstruction. This work aimed at analyzing characteristics and factors associated with development of hepatocellular carcinoma (HCC) in patients with primary BCS. METHODS: A total of 348 Egyptian BCS patients were included. They were presented to the Budd-Chiari Study Group of Ain Shams University Hospital. BCS was confirmed using abdominal Doppler US. Abdominal magnetic resonance imaging (MRI), MR venography and/or multislice computed tomography (CT) were performed to confirm all diagnoses and to assess vascular anatomy. Hepatic focal lesions detected during the study period (2005-2011) were evaluated using serum alpha foetoprotein (AFP) level, imaging features and histopathological examination. RESULTS: Diagnosis of HCC was confirmed in 15/348 patients (4.3%). Imaging studies showed that 60% had multiple hepatic focal lesions ranging from 2 to 6.3 cm in size. The median level of serum AFP in BCS with HCC was 300 ng/mL vs 11 ng/mL in those without HCC (P<.001). A cut-off level >24.5 ng/mL for serum AFP showed sensitivity 80%, specificity 97.9%, positive predictive value 93.18% and negative predictive value 99.1% for detection of HCC in BCS patients. Male gender, older age, cigarette smoking, serum AFP (>24.5 ng/mL) and shrunken liver by ultrasonography were independent factors associated with HCC development. CONCLUSION: Male gender, older age and cigarette smoking are independent risk factors for development of HCC in BCS. Serum AFP is a good screening test in BCS.