Relationship between HLA-DRB1*0101, DRB1*0301 alleles and interleukin-12 in haemophilic patients and hepatitis C virus positive hepatocellular carcinoma patients

The immune system can effectively eliminate hepatitis C virus (HCV) in 15 % of acute hepatitis cases. It is assumed that certain HLA-DR alleles present HCV epitopes more effectively to CD4 helper T cells than do others resulting in vigorous proliferative response to these epitopes and probably HCV recovery. So, we aimed at investigating the frequency of HLA-DRB1*0101 and DRB1*0301 alleles in child and adult haemophilics and in HCV positive hepatocellular carcinoma (HCC) patients in a trial to predict patients who require early therapeutic intervention. We also evaluated interleukin (IL)-12 levels in these patients since IL-12 induces interferon (IFN)-gamma production. This study was conducted on 50 antiHIV negative male patients subdivided into: 25 HCV negative haemophilics (group I), 10 HCV positive haemophilics (group II) and 15 HCV positive HCC (group III). Fifteen healthy persons of matched age and free of HCV and HIV infections were chosen as controls (group IV). All patients and controls were subjected to thorough history taking and clinical examination, routine and diagnostic investigations, viral markers, DRB1*0101 and DRB1*0301 amplification by polymerase chain reaction and plasma IL-12 quantitation by enzyme linked immunosorbent assay (ELISA). The frequencies of DRB1*0101 and DRB1*0301 were 20% and 30% respectively in HCV positive haemophilics and 13.3% and 40%, respectively in HCC. IL-12 levels were significantly lower in HCC cases than in HCV positive haemophilics. Among the haemophilics, IL-12 levels were non-significantly higher in children than in adults and were associated with the given number of blood product bags. DRB1*0101 and DRB1*0301 may have a role in HCV clearance and persistence in Egyptian patients with haemophilia and HCC. Low IL-12 levels encountered in HCV positive haemophilics suggest its relation to immunopathogenesis and outcome of HCV infection.     

Instant and quantitative epoxidation of styrene under ambient conditions over a nickel(ii)dibenzotetramethyltetraaza[14]annulene complex immobilized on amino-functionalized SBA-15

Nickel(ii)dibenzotetramethyltetraaza[14]annulene complex (Nitmtaa) was synthetized and immobilized on post amino-functionalized SBA-15 (N-SBA-15) to obtain a stable and reusable nanocatalyst named as Nitmtaa@N-SBA-15. Here (3-aminopropyl)triethoxysilane (APTES) was first grafted on the surface SBA-15, then Nitmtaa was added and coordinated on the silica surface via APTES amine groups. The structure and morphology, and thermal stability of the prepared nanocatalyst was investigated using SEM, HR-TEM, BET, FT-IR, powder XRD, and TGA. HR-TEM and XRD results revealed a high dispersion of Nitmtaa on the SBA-15 surface. The catalytic activity of this nanocatalyst was evaluated in the epoxidation of styrene, under ambient conditions, using meta-chloroperoxybenzoic acid (m-CPBA) as the oxygen donor. This nanocatalyst showed an immediate and quantitative epoxidation of styrene with high turn-over-frequency ∼31.58 s⁻¹. Moreover, the superior catalytic activity and high stability of Nitmtaa@N-SBA-15 could be maintained after four successive cycles. A possible reaction mechanism is also proposed.

Immediate and quantitative epoxidation of styrene under ambient conditions catalyzed by new nanocatalyst obtained by immobilizing nickel(ii)dibenzotetramethyltetraaza[14]annulene in amino-functionalized SBA-15.     

Discovery and antiproliferative evaluation of new quinoxalines as potential DNA intercalators and topoisomerase II inhibitors

In continuation of our previous work on the design and synthesis of topoisomerase II (Topo II) inhibitors and DNA intercalators, a new series of quinoxaline derivatives were designed and synthesized. The synthesized compounds were evaluated for their cytotoxic activities against a panel of three cancer cell lines (Hep G‐2, Hep‐2, and Caco‐2). Compounds 18b, 19b, 23, 25b , and 26 showed strong potencies against all tested cell lines with IC₅₀ values ranging from 0.26 ± 0.1 to 2.91 ± 0.1 µM, comparable with those of doxorubicin (IC₅₀ values ranging from 0.65 ± 0.1 to 0.81 ± 0.1 µM). The most active compounds were further evaluated for their Topo II inhibitory activities and DNA intercalating affinities. Compounds 19b and 19c exhibited high activities against Topo II (IC₅₀ = 0.97 ± 0.1 and 1.10 ± 0.1 µM, respectively) and bound the DNA at concentrations of 43.51 ± 2.0 and 49.11 ± 1.8 µM, respectively, whereas compound 28b exhibited a significant affinity to bind the DNA with an IC₅₀ value of 37.06 ± 1.8 µM. Moreover, apoptosis and cell‐cycle tests of the most promising compound 19b were carried out. It was found that 19b can significantly induce apoptosis in Hep G‐2 cells. It has revealed cell‐cycle arrest at the G2/M phase. Moreover, compound 19b downregulated the Bcl‐2 levels, indicating its potential to enhance apoptosis. Furthermore, molecular docking studies were carried out against the DNA–Topo II complex to examine the binding patterns of the synthesized compounds.     

A truncating mutation in B3GNT1 causes severe Walker–Warburg syndrome

Walker–Warburg syndrome (WWS) is a genetically heterogeneous form of congenital muscular dystrophy with significant brain and ocular involvement. In a multiplex consanguineous family with severe WWS phenotype, autozygome-guided sequencing of previously reported WWS genes was negative. Exome sequencing followed by autozygome filtration revealed a homozygous two-base pair insertion in B3GNT1 (NM_006876.2:c.821_822insTT), leading to premature truncation of the protein (p.Glu274Aspfs*94). Recently, two missense mutations in this gene have been reported as probably causal in a family with WWS. This report describes the first truncating mutation in B3GNT1 and confirms that this gene, which plays a role in αDG glycosylation, is a bona fide disease gene in WWS.     

Methanolic extract of Chlorella vulgaris protects against sodium nitrite-induced reproductive toxicity in male rats

The current study aimed to investigate the protective potential of Chlorella Vulgaris (CV) extract against the reproductive dysfunction induced by sodium nitrite toxicity. Forty-five male Wistar albino rats were assigned into five groups (n = 9). Control group received normal saline orally for 3 months, CV-treated: administered CV extract (70 mg/kg.BW) orally for 3 months, sodium nitrite-treated: received sodium nitrite (80 mg/kg.BW) orally for 3 months, co-treated: simultaneously received CV along with sodium nitrite treatment, orally, daily for 3 months, and CV-pre-treated: pre-treated with CV extract for 4 weeks followed by simultaneous treatment with sodium nitrite and CV extract for additional 8 weeks. Treatment with sodium nitrite significantly decreased serum testosterone and follicle-stimulating hormone concentrations, sperm count, motility, and viability. Besides, it decreased testicular superoxide dismutase and glutathione peroxidase activities while increased malondialdehyde concentration. This effect of sodium nitrite was associated with degenerative, necrotic, vascular, and inflammatory changes in testicular tissues. Treatment of sodium nitrite-intoxicated rats with CV in co-treated and pre-treated groups significantly prevented sodium nitrite-induced alterations of sperm parameters, hormonal concentrations, testicular oxidative–antioxidant status, and histological architecture. This study indicates that CV extract ameliorates the reproductive dysfunction induced by sodium nitrite toxicity via improving reproductive hormonal levels and testicular antioxidant activities.     

Ubiquitination of inducible nitric oxide synthase is required for its degradation

Inducible nitric oxide synthase (iNOS) is responsible for nitric oxide (NO) synthesis from l-arginine in response to inflammatory mediators. We have previously shown that iNOS is degraded through the 26S proteasome. Targeting of proteins for proteasomal degradation may or may not require their covalent linkage to multiubiquitin chains (ubiquitination). In addition, ubiquitination of a protein can serve functions other than signaling proteolysis. In this context, it is not known whether iNOS is subject to ubiquitination or whether ubiquitination is required for its degradation. In this study, we show that iNOS, expressed in HEK293 cells or induced in primary bronchial epithelial cells, A549 cells, or murine macrophages, is subject to ubiquitination. To investigate whether iNOS ubiquitination is required for its degradation, HEK293T cells were cotransfected with plasmids containing cDNAs of human iNOS and of the dominant negative ubiquitin mutant K48R. Disruption of ubiquitination by K48R ubiquitin resulted in inhibition of iNOS degradation. ts20 is a mutant cell line that contains a thermolabile ubiquitin-activating enzyme (E1) that is inactivated at elevated temperature, preventing ubiquitination. Incubation of ts20 cells, stably expressing human iNOS, at the nonpermissive temperature (40 degrees C) resulted in inhibition of iNOS degradation and marked accumulation of iNOS. These studies indicate that iNOS is subject to ubiquitination and that ubiquitination is required for its degradation.