Molecular dynamics simulation on the low sensitivity of mutants of NEDD-8 activating enzyme for MLN4924 inhibitor as a cancer drug

MLN4924 is an experimental cancer drug known as inhibitor of NEDD8-activating enzyme (NAE). This anti-tumor candidate is a selective small-molecule inhibitor of NAE which is conjugated to cullin protein on Cullin-RING ligases (CRLs). This covalent modification actives cullin complex to recruit an ubiquitin-charged E2 and leads to downstream target protein polyubiquitination and proteasomal degradation. MLN4924, which can form a covalent adduct with NEDD8, and block NAE at the first step in this pathway, has shown anti-tumor activity in many kinds of cancer cell lines and also xenograft models, including lung cancer, colon cancer, melanoma and lymphoma. The anti-tumor activity of MLN4924 results from inactivation of CLRs, which causes DNA re-replication and inhibition of nuclear factor (NF)-κB signaling, thus leading to cancer cell death. A mutation can reduce the enzyme’s sensitivity to MLN4924. Verma et al. in 2013 studied on molecular dynamics simulation of a mutant A171T and consequently found out that this mutation reduce MLN4924 interaction with DNA Binding site of enzyme as a result of reduction of enzyme affinity to ATP. One year later, in 2014, Wei Xu et al. carried out a research on inhibitor resistant cell lines and revealed that a couple of mutations so called Y352H and I310N leads to enzyme resistance to MLN4924 inhibitor, interestingly, the cause reported was the increase of enzyme affinity to ATP. As in Wei Xu et al. experiment the molecular dynamics simulation was not considered, present study is conducted to identify enzyme mutation mechanism by molecular dynamics approach using advantages of Gromacs software version 4.5.6.     

Imaging data in COVID-19 patients: focused on echocardiographic findings

To assess imaging data in COVID-19 patients and its association with clinical course and survival and 86 consecutive patients (52 males, 34 females, mean age?=?58.8 year) with documented COVID-19 infection were included. Seventy-eight patients (91%) were in severe stage of the disease. All patients underwent transthoracic echocardiography. Mean LVEF was 48.1% and mean estimated systolic pulmonary artery pressure (sPAP) was 27.9 mmHg. LV diastolic dysfunction was mildly abnormal in 49 patients (57.6%) and moderately abnormal in 7 cases (8.2%). Pericardial effusion was present in 5/86 (minimal in size in 3 cases and mild- moderate in 2). In 32/86 cases (37.2%), the severity of infection progressed from “severe” to “critical”. Eleven patients (12.8%) died. sPAP and computed tomography score were associated with disease progression (P value?=?0.002, 0.002 respectively). Tricuspid annular plane systolic excursion (TAPSE) was significantly higher in patients with no disease progression compared with those who deteriorated (P value?=?0.005). Pericardial effusion (minimal, mild or moderate) was detected more often in progressive disease (P?=?0.03). sPAP was significantly lower among survivors (P value?=?0.007). Echocardiographic findings (including systolic PAP, TAPSE and pericardial effusion), total CT score may have prognostic and therapeutic implication in COVID-19 patients.

     

Development trends for generation of single-chain antibody fragments

Recombinant antibodies are increasingly being employed as therapeutic agents especially in combination with anti-cancer drugs. The single-chain antibody fragments are small antigen-binding proteins which provide the most commonly used antibody formats for diagnostic and therapeutic purposes. These antibody fragments have more rapid tumor penetration and clearance from the serum relative to full-length monoclonal antibodies. There are in vitro antibody-display technologies such as phage display, cell surface display, ribosome display and mRNA display that can be used to isolate high specificity and affinity single-chain antibodies against a wide variety of targets. We review these strategies for generation of stable and active antibody fragments in the present article.     

Potential Roles of MyomiRs in Cardiac Development and Related Diseases

Muscle-specific miRNAs, which are known as MyomiRs, are crucial regulatory elements for cardiovascular development. MyomiRs are abundantly expressed in the myocardium and regulate certain aspects of physiological and pathological processes in myocardiocytes, including cardiovascular development, myocardial remodeling, and arise for cardiovascular diseases through different mechanisms, such as epigenetic pathways. Clinical and experimental studies have confirmed the myomiRs as promising diagnostic biomarkers for the early diagnosis of cardiac disorders. In this review, we have summarized recent findings in the field of epigenetic modulations of myomiRs and cardiac regeneration associated with cardiac diseases.     

Herbal medicine as a promising therapeutic approach for the management of vascular dementia: A systematic literature review

Vascular dementia (VaD) generally refers to memory deficits and cognitive abnormalities that are resulted from vascular disease. In this study, we aimed to systematically review the literature wherein therapeutic effects of medicinal plants have been studied on VaD. A systematic literature search was performed in the PubMed, Scopus, Web of Science, Google Scholar, and other databases using VaD, and medicinal plants as key terms. No strict inclusion criteria were defined, and almost all clinical studies were included. A total of 524 articles were found, of which only 28 relevant articles with 3461 studied patients were included to this systematic review. The results showed that medicinal plants, particularly Sancaijiangtang and Ginkgo biloba could improve behavioral and psychological symptoms, working memory, Mini‐Mental State Examination, and activities of daily living as well as neuropsychiatric features. It was also shown that the age, average progression of the disease, and the type of folk medicines effective in treating the disease are important factors in the management of VaD. The results of this review indicated that herbal therapy can be a potential candidate in the treatment of VaD; however, further studies are needed to confirm such efficiency.