Elucidating the significance of molecular interaction between sulphur doped zinc oxide nanoparticles and serum albumin using multispectroscopic approach.

Ingenious nanomaterials with improved biocompatibility and multifunctional properties are gaining vital significance in biomedical applications, including advanced drug delivery and nanotheranostics. In a biological system, these nanoparticles interact with serum proteins forming a dynamic corona that affects their biological or toxicological properties producing undesirable effects. Thus, the current study focuses on the synthesis of sulphur-doped zinc oxide nanoparticles (ZnO/S NPs) and characterizing their mechanism of interaction with serum proteins using multispectroscopic approach. ZnO/S NPs were synthesized by employing a co-precipitation approach and characterized using various analytical techniques. The results of interaction studies demonstrated that ZnO/S NPs interact with serum albumins via the static quenching process. Analysis of thermodynamic parameters (ΔG, ΔH and ΔS) revealed that the binding process is spontaneous, exothermic and van der Waals force or hydrogen bonding plays a major role. The interaction of ZnO/S NPs with tyrosine residue in bovine serum albumin was established by synchronous fluorescence spectroscopy. In addition, the results of UV-visible, circular dichroism, Fourier transform infrared, Forster's resonance energy transfer theory and dynamic light scattering spectroscopic studies revealed that the ZnO/S NPs interact with albumin by inducing the conformational changes in secondary structure and reducing the α-helix content.

Implementing Logic Gates for Safer Immunotherapy of Cancer.

Targeting solid tumors with absolute precision is a long-standing challenge in cancer immunotherapy. The identification of antigens, which are expressed by a large fraction of tumors of a given type and, preferably, across various types, but not by normal cells, holds the key to developing safe, off-the-shelf immunotherapies. Although the quest for widely shared, strictly tumor-specific antigens has been the focus of tremendous effort, only few such candidates have been implicated. Almost all antigens that are currently explored as targets for chimeric antigen receptor (CAR) or T cell receptor (TCR)-T cell therapy are also expressed by healthy cells and the risk of on-target off-tumor toxicity has remained a major concern. Recent studies suggest that this risk could be obviated by targeting instead combinations of two or more antigens, which are co-expressed by tumor but not normal cells and, as such, are tumor-specific. Moreover, the expression of a shared tumor antigen along with the lack of a second antigen that is expressed by normal tissues can also be exploited for precise recognition. Additional cues, antigenic or non-antigenic ones, which characterize the tumor microenvironment, could be harnessed to further increase precision. This review focuses on attempts to define the targetable signatures of tumors and assesses different strategies employing advanced synthetic biology for translating such information into safer modes of immunotherapy, implementing the principles of Boolean logic gates.

Evaluation of cell wall-associated direct extracellular electron transfer in thermophilic Geobacillus sp.

In this study, a cell wall-associated extracellular electron transfer (EET) was determined in the thermophilic Geobacillus sp. to utilize iron as a terminal electron acceptor. The direct extracellular transfer of its electrons was primarily linked to the cell wall cytochrome-c and diffusible redox mediators like flavins during the anoxic condition. Based on the azo dye decolouration and protein film voltammetry, it was revealed that, in the absence of surface polysaccharide and diffusible mediators, the cell wall-associated EET pathway was likely to be a favorable mechanism in Geobacillus sp. Since the permeability of such redox molecule is primarily limited to the cell wall, the electron transfer occurs by direct contact with cell wall-associated cytochrome and final electron acceptor. Furthermore, transfer of electrons with the help of redox shuttling molecules like riboflavin from cytochrome to cells, vice versa indicates that Geoabcillus sp. has adopted this unique pathway during an anoxic environment for its respiration. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02917-2.

Molecular interaction studies of zinc sulphide nanoparticles with DNA and its consequence: a multitechnique approach.

Molecular interaction studies between nanoparticles (NPs) and biomolecules are of great importance in the field of nanomedicine as they affect many physiological processes. Therefore, the interaction of zinc sulphide nanoparticles (ZnS NPs) with calf thymus deoxyribonucleic acid (CT DNA) and its significance was analyzed using ultraviolet (UV)-visible light, fluorescence, circular dichroism (CD), zeta potential, viscometry, electrochemical, and polymerase chain reaction methods. Fluorescence quenching analysis revealed that the fluorescence of ZnS NPs was quenched using CT DNA through a static quenching mechanism. The negative values of thermodynamic parameters (ΔG, ΔH, and ΔS) showed that the binding process was spontaneous, exothermic, and van der Waals or hydrogen bonding plays an important role in the interaction of ZnS NPs with CT DNA. Thermal melting (Tm ) studies indicated a decrease in the Tm of CT DNA, suggesting the destabilization of CT DNA upon interaction with ZnS NPs. In addition, the results obtained from competitive binding, zeta potential, CD, and viscometry measurements showed that the interaction of ZnS NPs with CT DNA is through groove binding. Electrochemical analysis further confirmed the observed results from various spectroscopic and other related studies, in which decrease in the redox peak current along with changes in peak potential (CV) and increase in the electrical resistance (EIS) indicated the interaction between ZnS NPs and CT DNA. Furthermore, PCR analysis using DNA polymerase revealed the potential of ZnS NPs to inhibit DNA replication in vitro. ZnS NP-CT DNA interaction studies can be explored to define new horizons in biomedical applications of ZnS NPs.

Novel pyrazolo[3,4-d]pyrimidine derivatives inhibit human cancer cell proliferation and induce apoptosis by ROS generation.

The paucity of effective anticancer drugs for successful treatment is a major concern, indicating the strong need for novel therapeutic compounds. In the quest of new molecules, the present study aimed to explore the potential of pyrazolo[3,4-d]pyrimidine derivatives as antiproliferative agents. In vitro anticancer screening of selected compounds was done by the National Cancer Institute's Developmental Therapeutics Programme against a panel of 60 cancer cell lines. The lead compound PP-31d considerably inhibited the growth of cancer cells, such as NCI-H460 (non-small-cell lung cancer), OVCAR-4 (ovarian cancer), 786-0 (renal cancer), A549 (non-small-cell lung cancer), and ACHN (renal cancer), showing strong anticancer potential, among other derivatives. Kinetic studies of PP-31d on NCI-H460 cells revealed a dose-dependent effect with an IC50 of 2 µM. The observed inhibition by PP-31d is attributed to the generation of reactive oxygen species and the subsequent induction of cellular apoptosis, as evidenced by the increase in the hypodiploid (subG1) population, the early apoptotic cell population, and caspase-3/7 activity, the loss of the mitochondrial membrane potential, and the degradation of nuclear DNA. Collectively, our results demonstrated that pyrazolo[3,4-d]pyrimidine derivatives inhibit cancer cell proliferation by inducing apoptosis and, thus, have the potential to be further explored for anticancer properties.

A manganese oxide nanozyme prevents the oxidative damage of biomolecules without affecting the endogenous antioxidant system.

Biocompatible nanoparticles with an intrinsic ability to mimic the cellular antioxidant enzymes are potential candidates for the development of new therapeutics for various oxidative stress related disorders. However, the understanding of the interaction and the mechanistic crosstalk between the nanoparticles and the cellular biomolecules is limited. Here we show that the multienzyme mimic manganese(ii,iii) oxide, Mn3O4, in nanoform (Mp) rescues the cells from oxidative damage induced by reactive oxygen species (ROS). The nanoparticles provide remarkable protection to biomolecules against the ROS-mediated protein oxidation, lipid peroxidation and DNA damage. Interestingly, the endogenous antioxidant machinery remains unaltered in the presence of these nanozymes, indicating the small molecule targeting of these nanoparticles in the cellular redox modulation. This study delineates the possible mechanism by which the nanoparticles provide protection to the cells against the adverse effects of oxidative stress. Based on our observation, we suggest that the multienzyme mimic Mn3O4 nanoparticles possess great potential in suppressing the oxidative stress-mediated pathophysiological conditions under which the antioxidant system is overwhelmed.

Effects of methyl jasmonate and carotenogenic inhibitors on gene expression and carotenoid accumulation in coriander (Coriandrum sativum L.) foliage.

Coriander (Coriandrum sativum L.), a commonly used annual herb that accumulates carotenoids upon methyl jasmonate (MeJA) treatment, provides an excellent model to investigate carotenogenesis and gene regulation. To explore key mechanisms involved in enhancing carotenoids, transcriptional expression profile of ten carotenogenic genes in the presence of MeJA and various gene specific inhibitors were investigated. Foliar application of MeJA (10 µM) increased expression levels of CsPDS (phytoene desaturase), CsZDS (ς-carotene desaturase), CsCHYE (carotene ε - hydroxylase) and CsLCYE (lycopene ß-cyclase) genes, and their transcript levels were strongly associated with carotenoid content, where, three days after treatment, 3.9 & 6.1 fold increase was observed for ß-carotene and lutein respectively. The regulatory effect of key genes, CsPDS, CsZDS, CsLCYE and LCYB were further confirmed by using gene-specific inhibitors fosmidomycin, norflurazon and amitrol. Norflurazon- the phytoene desaturation inhibitor leads to a decrease in ß-carotene and lutein content correlated with CsPDS, CsZDS gene induction. Our results clearly demonstrate that MeJA induced-signalling network evokes carotenogenic genes, leading to the accumulation of carotenoids. This knowledge may help to develop precise strategies for remodelling carotenoid pathway so that desired levels of a particular carotenoid in leafy vegetables is achievable.

Novel Folate Binding Protein in Arabidopsis Expressed during Salicylic Acid-Induced Folate Accumulation.

Increasing the quantity of natural folates in plant foods is recently gaining significant interest, owing to their acute deficiencies in various populations. This study observed that foliar salicylic acid treatment enhanced the accumulation of folates in Arabidopsis, which correlated with the increase in a folate binding protein (FBP) and the expression of mRNA of a putative folate binding protein At5G27830. A protein band corresponding to ∼43 kDa was observed after resolving the affinity-purified protein on SDS-PAGE, and the partial amino acid sequence indicated that the protein is indeed At5G27830. Docking studies performed with At5G27830 confirmed specific binding of folic acid to predicted site. Heterologous expression of At5G27830 in the yeast resulted in significant uptake and accumulation of folic acid in cells. This novel study of a plant FBP will be useful for folate metabolic engineering of a wide range of crops.

Emerging concepts and spectrum of renal injury following Intravesical BCG for non-muscle invasive bladder cancer.

BACKGROUND: Intravesical Bacilli Calmette-Guerin (IVBCG) therapy for non-muscle invasive bladder cancer (NMIBC) has long been in use successfully. Albeit rarely, we still face with its safety concerns more than 25 years on since its approval by US Food and Drug Agency in 1990. Local and systemic infection following intravesical BCG is widely reported as compared to immune mediated local or systemic hypersensitivity reactions involving kidneys; acute kidney injury (AKI) and other renal manifestations are well reported but not of chronic kidney disease (CKD). CASE: An interesting case of a female was referred to nephrologists in advanced stages of CKD at an eGFR of 10 ml/min/1.732 following IVBCG for NMIBC. Our patient's renal function plateaued when IVBCG was held; and worsened again when reinstilled. It introduces the concept of 'repetitive' immune mediated renal injury presenting as progressive CKD rather than AKI, as is generally reported. Although response was poor, corticosteroids stopped CKD progression to end stage renal disease. CONCLUSIONS: We highlight the need for increased awareness and early recognition of IVBCG renal complications by both urologists and nephrologists in order to prevent progressive and irreversible renal damage. Low incidence of IVBCG renal complications may also be due to under recognition in the era prior to CKD Staging and AKI Network (and AKI e-alerts) that defined AKI as a rise in serum creatinine of ≥26umol/L; hence an unmet need for urgent prospective studies. Major literature review focuses on emerging spectrum of histopathological IVBCG related renal complications and their outcomes.

A Redox Modulatory Mn3 O4 Nanozyme with Multi-Enzyme Activity Provides Efficient Cytoprotection to Human Cells in a Parkinson's Disease Model.

Nanomaterials with enzyme-like activities (nanozymes) attracts significant interest due to their therapeutic potential for the treatment of various diseases. Herein, we report that a Mn3 O4 nanozyme functionally mimics three major antioxidant enzymes, that is, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and the multienzyme activity is size as well as morphology-dependent. The redox modulatory effect of Mn3 O4 plays a crucial role in protecting the cells from MPP+ induced cytotoxicity in a Parkinson disease (PD)-like cellular model, indicating that manganese-based nanomaterials having multi-enzyme activity can robustly rescue the cells from oxidative damage and thereby possess therapeutic potential to prevent ROS-mediated neurological disorders.

Epigallocatechin gallate protects BEAS-2B cells from lipopolysaccharide-induced apoptosis through upregulation of gastrin-releasing peptide.

Gastrin-releasing peptide (GRP) plays a major role in the development and maintenance of lung epithelial cells by promoting cell division, whereas its suppression causes growth arrest and apoptosis. The present study shows that human bronchial epithelial BEAS-2B cells challenged with lipopolysaccharide (LPS), an endotoxin from gram-negative bacteria, downregulated GRP expression and induced apoptosis via upregulation of p53 and active caspase-3, signifying the importance of GRP in lung epithelial cell survival. However, in the presence of epigallocatechin-3-gallate (EGCG), a polyphenol in green tea, BEAS-2B cells resisted LPS-induced apoptosis and restored the expression of GRP and its downstream effectors such as epidermal growth factor receptor and NF-κB, as analysed by immunoblotting and qPCR. Based on our findings, we objectify that cytoprotective functions of EGCG, via upregulation of GRP in cells challenged with LPS, are novel and can be further explored in a therapeutic point of view for diseases such as septic shock.

Intradialytic Cardiac Magnetic Resonance Imaging to Assess Cardiovascular Responses in a Short-Term Trial of Hemodiafiltration and Hemodialysis.

Hemodynamic stress during hemodialysis (HD) results in recurrent segmental ischemic injury (myocardial stunning) that drives cumulative cardiac damage. We performed a fully comprehensive study of the cardiovascular effect of dialysis sessions using intradialytic cardiac magnetic resonance imaging (MRI) to examine the comparative acute effects of standard HD versus hemodiafiltration (HDF) in stable patients. We randomly allocated 12 patients on HD (ages 32-72 years old) to either HD or HDF. Patients were stabilized on a modality for 2 weeks before undergoing serial cardiac MRI assessment during dialysis. Patients then crossed over to the other modality and were rescanned after 2 weeks. Cardiac MRI measurements included cardiac index, stroke volume index, global and regional contractile function (myocardial strain), coronary artery flow, and myocardial perfusion. Patients had mean±SEM ultrafiltration rates of 3.8±2.9 ml/kg per hour during HD and 4.4±2.5 ml/kg per hour during HDF (P=0.29), and both modalities provided a similar degree of cooling. All measures of systolic contractile function fell during HD and HDF, with partial recovery after dialysis. All patients experienced some degree of segmental left ventricular dysfunction, with severity proportional to ultrafiltration rate and BP reduction. Myocardial perfusion decreased significantly during HD and HDF. Treatment modality did not influence any of the cardiovascular responses to dialysis. In conclusion, in this randomized, crossover study, there was no significant difference in the cardiovascular response to HDF or HD with cooled dialysate as assessed with intradialytic MRI.

Predicting non-diabetic renal disease in type 2 diabetic adults: The value of glycated hemoglobin.

AIMS: The indications for renal biopsy in type 2 diabetes mellitus (T2D) are not well established. We investigated the prevalence, spectrum, and predictors of biopsy-proven non-diabetic renal disease (NDRD) in T2D. METHODS: An observational, single-center, retrospective study of T2D adults who underwent renal biopsies (N = 51) over 10 years for nephrotic-range proteinuria, microscopic hematuria, or rapidly declining renal function. RESULTS: Thirty-five (68.6%) biopsies were diagnostic of NDRD, and 16 (31.4%) revealed isolated diabetic nephropathy. The most common NDRDs were interstitial nephritis (20%), progressive crescentic glomerulonephritis (14%), membranous nephropathy (11%), and focal segmental glomerulosclerosis (11%). The odds for NDRD declined by 97% in the presence of diabetic retinopathy (P < 0.001). The deterioration of HbA1c during the year before biopsy predicted NDRD even after adjusting for diabetic retinopathy (OR, 7.65; 95% CI, 1.36-123.04; P = 0.003). A model based on the interaction between the HbA1c values 12 months before biopsy and the absolute change in these values during the preceding year predicted NDRD with 73.7% sensitivity and 75% specificity (AUC, 0.77; 95% CI, 0.59-0.94). CONCLUSIONS: This study demonstrated a considerably high prevalence of NDRD in T2D adults undergoing renal biopsy. The absence of diabetic retinopathy, lower HbA1c values 12 months before biopsy and greater deterioration in HbA1c prior to biopsy predicted NDRD in T2D. Further studies are needed to validate the findings.

Sclerotium rolfsii lectin induces stronger inhibition of proliferation in human breast cancer cells than normal human mammary epithelial cells by induction of cell apoptosis.

Sclerotium rolfsii lectin (SRL) isolated from the phytopathogenic fungus Sclerotium rolfsii has exquisite binding specificity towards O-linked, Thomsen-Freidenreich (Galß1-3GalNAcα1-Ser/Thr, TF) associated glycans. This study investigated the influence of SRL on proliferation of human breast cancer cells (MCF-7 and ZR-75), non-tumorigenic breast epithelial cells (MCF-10A) and normal mammary epithelial cells (HMECs). SRL caused marked, dose-dependent, inhibition of proliferation of MCF-7 and ZR-75 cells but only weak inhibition of proliferation of non-tumorigenic MCF-10A and HMEC cells. The inhibitory effect of SRL on cancer cell proliferation was shown to be a consequence of SRL cell surface binding and subsequent induction of cellular apoptosis, an effect that was largely prevented by the presence of inhibitors against caspases -3, -8, or -9. Lectin histochemistry using biotin-labelled SRL showed little binding of SRL to normal human breast tissue but intense binding to cancerous tissues. In conclusion, SRL inhibits the growth of human breast cancer cells via induction of cell apoptosis but has substantially less effect on normal epithelial cells. As a lectin that binds specifically to a cancer-associated glycan, has potential to be developed as an anti-cancer agent.

Retroperitoneum: a forgotten and fatal aspect of kidney biopsy.

A kidney biopsy is an important tool for nephrologists in the diagnosis of renal conditions, but not without the risk of bleeding due to its invasive nature. There is abundance of literature on bleeding complications secondary to this procedure in high-risk patient groups such as amyloidosis and chronic hypertension. An undefined and unrecognized risk is a peritoneal penetration. We report here a case where, despite adequately preparing a patient for a kidney biopsy, distortion of the peritoneum and retroperitoneum from previous surgery resulted in a fatal outcome. This was due to loss of peritoneal integrity and the consequent loss of local anatomical hemostatic mechanism.

Prevalence of nonalcoholic fatty liver disease (NAFLD) in patients of cardiovascular diseases and its association with hs-CRP and TNF-α.

BACKGROUND: There is increasing recognition of association of nonalcoholic fatty liver disease (NAFLD) with cardiovascular disease (CVD). Metabolic syndrome is common in both NAFLD and cardiovascular diseases. Our study is designed to investigate the association of NAFLD with cardiovascular disease. METHODS: It's a cross-sectional study which included 104 patients of coronary artery disease and hypertensive heart disease. Those patients having secondary causes of steatosis were excluded. Complete cardiovascular evaluation which included assessment of metabolic syndrome, routine biochemistries, viral markers, Ultrasonography (USG) abdomen, hs-CRP and TNF-α levels were obtained for all patients. RESULTS: Of all patients with cardiovascular disease, 19.2% (20/104) had essential hypertension with hypertensive heart disease the remaining 80.8% (84/104) patients had ischemic heart disease (IHD). On USG 69.2% (72/104) had NAFLD, these 50% (36/72) had grade 1 NAFLD and the rest grade 2 NAFLD. The hs-CRP levels and TNF-α were significantly higher in patients with NAFLD (p-value <0.001) and within patients with NAFLD the levels were higher in patients with grade 2 NAFLD. Also, binary logistic regression showed that high body-mass index (BMI), raised serum triglyceride levels, increased waist circumference and hypertension were significantly associated with the presence of NAFLD. CONCLUSION: Our data indicates that NALD is highly prevalent in patients of cardiovascular disease (69.2%) and is significantly associated with metabolic syndrome and its individual components. The levels of hs-CRP and TNF-α were significantly higher in patients with NAFLD and showed an increasing trend with the severity of fatty liver.

The TF-antigen binding lectin from Sclerotium rolfsii inhibits growth of human colon cancer cells by inducing apoptosis in vitro and suppresses tumor growth in vivo.

Glycan array analysis of Sclerotium rolfsii lectin (SRL) revealed its exquisite binding specificity to the oncofetal Thomsen-Friedenreich (Galß1-3GalNAcα-O-Ser/Thr, T or TF) antigen and its derivatives. This study shows that SRL strongly inhibits the growth of human colon cancer HT29 and DLD-1 cells by binding to cell surface glycans and induction of apoptosis through both the caspase-8 and -9 mediated signaling. SRL showed no or very weak binding to normal human colon tissues but strong binding to cancerous and metastatic tissues. Intratumor injection of SRL at subtoxic concentrations in NOD-SCID mice bearing HT29 xenografts resulted in total tumor regression in 9 days and no subsequent tumor recurrence. As the increased expression of TF-associated glycans is commonly seen in human cancers, SRL has the potential to be developed as a therapeutic agent for cancer.