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Diabetic nephropathy (DN) is a major healthcare challenge for individuals with diabetes and associated with increased cardiovascular morbidity and mortality. The existing rodent models do not fully represent the complex course of the human disease. Hence, developing a translational model of diabetes that reproduces both the early and the advanced characteristics of DN and faithfully recapitulates the overall human pathology is an unmet need. Here, we introduce the Nile grass rat (NGR) as a novel model of DN and characterize key pathologies underlying DN. NGRs spontaneously developed insulin resistance, reactive hyperinsulinemia, and hyperglycemia. Diabetic NGRs evolved DN and the key histopathological aspects of the human advanced DN, including glomerular hypertrophy, infiltration of mononuclear cells, tubular dilatation, and atrophy. Enlargement of the glomerular tufts and the Bowman's capsule areas accompanied the expansion of the Bowman's space. Glomerular sclerosis, renal arteriolar hyalinosis, Kimmelsteil–Wilson nodular lesions, and protein cast formations in the kidneys of diabetic NGR occurred with DN. Diabetic kidneys displayed interstitial and glomerular fibrosis, key characteristics of late human pathology as well as thickening of the glomerular basement membrane and podocyte effacement. Signs of injury included glomerular lipid accumulation, significantly more apoptotic cells, and expression of KIM‐1. Diabetic NGRs became hypertensive, a known risk factor for kidney dysfunction, and showed decreased glomerular filtration rate. Diabetic NGRs recapitulate the breadth of human DN pathology and reproduce the consequences of chronic kidney disease, including injury and loss of function of the kidney. Hence, NGR represents a robust model for studying DN‐related complications and provides a new foundation for more detailed mechanistic studies of the genesis of nephropathy, and the development of new therapeutic approaches. [ABSTRACT FROM AUTHOR]

Aim: To develop a novel nanovector for the delivery of genetic fragments and CRISPR/Cas9 systems in particular. Materials & methods: Vitamin D3-functionalized carbon dots (D/CDs) fabricated using one-step microwave-aided methods were characterized by different microscopic and spectroscopic techniques. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay and flow cytometry were employed to determine the cell viability and transfection efficiency. Results: D/CDs transfected CRISPR plasmid in various cell lines with high efficiency while maintaining their remarkable efficacy at high serum concentration and low plasmid doses. They also showed great potential for the green fluorescent protein disruption by delivering two different types of CRISPR/Cas9 systems. Conclusion: Given their high efficiency and safety, D/CDs provide a versatile gene-delivery vector for clinical applications. [ABSTRACT FROM AUTHOR]

Aims: DLL4 of the Notch pathway is a key regulator of VEGF expression, which mediates tumor neovascularization and stem cell self-renewal in colorectal cancer (CRC). The authors investigated the association of DLL4 expression with the clinicopathological characteristics and survival outcomes of CRC patients. Methods: DLL4 expression level was evaluated in 199 CRC samples using immunohistochemistry analysis of tissue microarrays. Results: The high expression of DLL4 was inversely associated with distant metastasis (p < 0.029), tumor recurrence (p < 0.04) and longer overall survival following curative surgery compared with those with low DLL4 expression with 95% CI (log-rank test: p = 0.050). In univariate analysis, histological grade (hazard ratio: 3.859; 95% CI: 1.081-13.784; p = 0.038) was a strong prognostic risk factor, affecting the overall survival of CRC patients. Conclusion: The authors' results demonstrate that DLL4 expression might be considered a favorable prognostic factor for overall survival in CRC patients. [ABSTRACT FROM AUTHOR]

The development of efficient and repeatable protocols for biobanking and prolonged storage of cancer stem cells (CSCs), with minimum alterations in biological function, is valuable and desired, particularly for retrospective analysis and clinical applications. In particular, data regarding the effect of cryopreservation on CSCs's functional features is scarce. In this regard, few studies have been shown that 3D spheroid structures, which enriched for CSCs, can keep their biological phenotype and genetic profiles. Here, for the first time, we present data on cryopreservation of CT‐26 colonospheres, with the focus on essential stem cell‐like properties after thawing. Tumor biopsy‐derived colonospheres were frozen in standard freezing media (90% fetal bovine serum + 10% dimethyl sulfoxide) and stored in liquid nitrogen for 10 months. Then, cryopreservation effect on preservation of CSCs‐related features was verified using real‐time polymerase chain reaction for evaluation of stemness genes and flow cytometry for the putative colorectal CSC surface biomarkers. The self‐renewal capacity of thawed spheres was also compared with their fresh counterparts using serial formation assay. Finally, tumorigenic capacity of both groups was evaluated in immunocompetence mouse model. Our data indicated that postthawed colonospheres had high viability without drastic alteration in biological and structural features and maintained self‐renewal potential after sequential passages. Real‐time analysis showed that both fresh and frozen colonospheres displayed similar expression pattern for key stemness genes: SOX2 and OCT4. Cryopreserved spheroids expressed CD133, CD166, and DCLK1 CSCs surface biomarkers at elevated levels when compared with parental as non‐cryopreserved counterparts. Our electron scanning microscopy micrographs clearly demonstrated that postthawed colonospheres retain their integrity and cell surface morphology and characteristics. We also found that both fresh and frozen spheroids were equally tumorigenic. This study represented an effective strategy for reliable storage of intact CT‐26 colonospheres; this can provide researchers with a functionally reliable repository of murine colorectal CSCs for their future CSCs projects. [ABSTRACT FROM AUTHOR]

Background: We aimed to determine the contribution of four DFNB loci and mutation analysis of gap junction beta-2 (GJB2) and GJB4 genes in autosomal recessive nonsyndromic hearing loss (ARNSHL) in South of Iran. Materials and Methods: A total of 36 large ARNSHL pedigrees with at least two affected subjects were enrolled in the current study. The GJB2 and GJB4 genes mutations were screened using direct sequencing method. The GJB2 and GJB4 negative families were analyzed for the linkage to DFNB21, DFNB24, DFNB29, and DFNB42 loci by genotyping the corresponding STR markers using polymerase chain reaction-PAGE method. Results: We found a homozygous nonsense mutation W77X and a homozygous missense mutation C169W in 5.55% of studied families in GJB2 and GJB4 genes, respectively. Five heterozygous mutations including V63G, A78T, and R127H in GJB2 gene, and R103C and R227W in GJB4 gene were detected. We identified two novel variations V63G in GJB2 and R227W in GJB4. In silico analysis predicted that both novel variations are deleterious mutations. We did not unveil any linkage between DFNB21, DFNB24, DFNB29, and DFNB42 loci and ARNSHL among studied families. Conclusion: This is the first report of GJB2 and GJB4 mutations from Hormozgan population. According to the previous publications regarding GJB2 and GJB4 mutations, the distribution of the mutations is different from other parts of Iran that should be considered in primary health-care programs. Further investigations are needed to evaluate the contribution of other loci in ARNSHL subjects in South of Iran. [ABSTRACT FROM AUTHOR]

Background: The octamer-binding transcription factor-4 (OCT4) is known as an established important regulator of pluripotency, as well as a genetic "master switch" in the self-renewal of embryonic stem and germ cells. OCT4B1 , one of the three spliced variants of human OCT4, plays crucial roles in the regulation of pluripotency and stemness., Objectives: The present study developed a transgenic mouse model containing an OCT4B1 -expressing construct under the transcriptional direction of mouse mammary tumor virus promoter (pMMTV) to evaluate the role of OCT4B1 in the function of male germ cells in terms of fertility potential. Additionally, the effect of ectopic OCT4B1 overexpression on endogenous OCT4 expression was examined in mouse embryonic stem cells (mESCs)., Material and Methods: The pMMTV-OCT4B1cDNA construct was injected into the pronuclei of 0.5-day NMRI embryos. Transgenic mice were identified based on the PCR analysis of tail DNA. Further, Diff-Quik staining was applied to assess sperm morphology, while the other sperm parameters were analyzed through a conventional light microscopic evaluation according to World Health Organization (WHO) criteria. The fertility rate was scored by using in vitro frtilization (IVF) method. Furthermore, mESCs was electroporated with the OCT4B1cDNA -containing constructs, followed by analyzing through employing semi-quantitative RT-PCR and western blotting., Results: The results demonstrated the changes in sperm morphology, as well as a statistically significant decrease in the other sperm parameters (count, viability, and motility) and fertility rate (p<0.05) in the transgenic mice compared with the control group. The assessment of the cause of the embryonic stem cell (ESC) death following transfection revealed a significant reduction in the endogenous OCT4 expression at both mRNA and protein levels in the transfected mESCs compared to the control ones., Conclusion: In general, the in vivo results suggested a potential role of OCT4B1 in the spermatogenesis process. These results represented that the overexpression of OCT4B1 may induce its role in spermatogenesis and fertility rate by interfering endogenous OCT4 expression. However, further studies are required to clarify the mechanisms underlying OCT4B1 function., (Copyright: © 2021 The Author(s); Published by Iranian Journal of Biotechnology.)

Aim: To develop a novel nanovector for the delivery of genetic fragments and CRISPR/Cas9 systems in particular. Materials & methods: Vitamin D 3 -functionalized carbon dots (D/CDs) fabricated using one-step microwave-aided methods were characterized by different microscopic and spectroscopic techniques. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay and flow cytometry were employed to determine the cell viability and transfection efficiency. Results: D/CDs transfected CRISPR plasmid in various cell lines with high efficiency while maintaining their remarkable efficacy at high serum concentration and low plasmid doses. They also showed great potential for the green fluorescent protein disruption by delivering two different types of CRISPR/Cas9 systems. Conclusion: Given their high efficiency and safety, D/CDs provide a versatile gene-delivery vector for clinical applications.

Background: Autosomal recessive non-syndromic hearing loss (ARNSHL) a most frequent hereditary type of hearing impairment, exhibit tremendous genetic heterogeneity. We aimed to determine the contribution of three common DFNB loci (DFNB4, DFNB28, and DFNB93), and mutation analysis of Gap Junction Beta-2 gene (GJB2) and GJB3 genes in ARNSHL subjects in southern Iran., Methods: Thirty-six large ARNSHL pedigrees (167 individuals) with at least two affected subjects (72 patients) were included in this descriptive study from Hormozgan Province of Iran, during 2014 - 2015. The variation of GJB2 and GJB3 genes were screened using direct sequencing method. The negative samples for GJB2 and GJB3 genes mutations were analyzed for the linkage to DFNB4, DFNB28, and DFNB93 loci by genotyping the corresponding short tandem repeat (STR) markers using polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) methods., Results: DNA sequencing of GJB2 were identified heterozygous mutation (964 C/T) in 13.88% of the studied families. Three missense mutations (788G/A, 284C/T and 973G/C) were also detected in coding region of the GJB3 gene. The 284C/T mutation in the GJB3 occurs in compound heterozygosity along with the 964T/C mutation in the GJB2 in one family. Finally, we found no evidence of linkage to either of DFNB4, DFNB93 and DFNB28 loci., Conclusion: Highlighting the hypothesis that a genetic interaction between GJB2 and GJB3 genes could be lead to ARNSHL, however, no evidence of linkage to the DFNB loci was found. 284C/T variant in GJB3 gene might be pathogenic when accompanied by variant in GJB2 in a digenic pattern. However, further large-scale familial and functional studies are required to challenge this hypothesis., Competing Interests: Conflict of interest The authors declare that there is no conflict of interest.