Synthesis and characterization of nickel oxide nanoparticles by self-propagating low temperature combustion method

Nickel Oxide (NiO) nanoparticles have been synthesised by self-propagating low temperature Combustion synthesis method using Nickel salt with polyethylene glycol as fuel. As synthesized NiO nanoparticles was characterized by employing Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy dispersive X-ray microanalysis studies (EDAX) techniques and X-ray diffraction (XRD) confirmed the formation of NiO nanoparticles in the range 20 to 40 nm. SEM images clearly shows the NiO particles are in Nano size.&nbsp

Photo-Irradiated Biosynthesis of Silver Nanoparticles Using Edible Mushroom Pleurotus florida and Their Antibacterial Activity Studies

This is a report on photo-irradiated extracellular synthesis of silver nanoparticles using the aqueous extract of edible oyster mushroom (Pleurotus florida) as a reducing agent. The appearance, size, and shape of the silver nanoparticles are understood by UV-visible spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The X-ray diffraction studies, energy dispersive X-ray analysis indicate that particles are crystalline in nature. Fourier transform infrared spectroscopy analysis revealed that the nanoparticles are covered with biomoieties on their surface. As can be seen from our studies, the biofunctionalized silver nanoparticles thus produced have shown admirable antimicrobial effects, and the synthetic procedure involved is eco-friendly and simple, and hence high range production of the same can be considered for using them in many pharmaceutical applications

Hsp72 (HSPA1A) Prevents Human Islet Amyloid Polypeptide Aggregation and Toxicity: A New Approach for Type 2 Diabetes Treatment

Type 2 diabetes is a growing public health concern and accounts for approximately 90% of all the cases of diabetes. Besides insulin resistance, type 2 diabetes is characterized by a deficit in β-cell mass as a result of misfolded human islet amyloid polypeptide (h-IAPP) which forms toxic aggregates that destroy pancreatic β-cells. Heat shock proteins (HSP) play an important role in combating the unwanted self-association of unfolded proteins. We hypothesized that Hsp72 (HSPA1A) prevents h-IAPP aggregation and toxicity. In this study, we demonstrated that thermal stress significantly up-regulates the intracellular expression of Hsp72, and prevents h-IAPP toxicity against pancreatic β-cells. Moreover, Hsp72 (HSPA1A) overexpression in pancreatic β-cells ameliorates h-IAPP toxicity. To test the hypothesis that Hsp72 (HSPA1A) prevents aggregation and fibril formation, we established a novel C. elegans model that expresses the highly amyloidogenic human pro-IAPP (h-proIAPP) that is implicated in amyloid formation and β-cell toxicity. We demonstrated that h-proIAPP expression in body-wall muscles, pharynx and neurons adversely affects C. elegans development. In addition, we demonstrated that h-proIAPP forms insoluble aggregates and that the co-expression of h-Hsp72 in our h-proIAPP C. elegans model, increases h-proIAPP solubility. Furthermore, treatment of transgenic h-proIAPP C. elegans with ADAPT-232, known to induce the expression and release of Hsp72 (HSPA1A), significantly improved the growth retardation phenotype of transgenic worms. Taken together, this study identifies Hsp72 (HSPA1A) as a potential treatment to prevent β-cell mass decline in type 2 diabetic patients and establishes for the first time a novel in vivo model that can be used to select compounds that attenuate h-proIAPP aggregation and toxicity

Joint Effect of MCP-1 Genotype GG and MMP-1 Genotype 2G/2G Increases the Likelihood of Developing Pulmonary Tuberculosis in BCG-Vaccinated Individuals

We previously reported that the – 2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the – 1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the – 2518 MCP-1 genotype GG and the – 1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1

Investigation of flexural properties of epoxy composite by utilizing graphene nanofillers and natural hemp fibre reinforcement

This study aims to determine the optimum reinforcement required to attain the best combination of flexural strength of modified green composites (graphene oxide + hemp fibre reinforced epoxy composites) for potential use in structural applications. An attempt was also made for the combination of graphene and hemp fibres to enhance load-bearing ability. The infusion of hemp and graphene was made by the weight of the base matrix (epoxy composite). Results showed that graphene reinforcement at 0.4 wt.% of matrix showed load-sustaining capacity of 0.76 kN or 760 MPa. In the case of hemp fibre reinforcement at 0.2 wt.% of the matrix, infusion showed enhanced load-bearing ability (0.79 kN or 790 MPa). However, the combination of graphene (0.1 wt.% graphene nanofillers) and hemp (5 wt.% hemp fibre) indicated a load-sustaining ability of 0.425 kN or 425 MPa, whereas maximum deflection was observed for specimen with hemp 7.5 % + graphene 0.2 % with 1.9 mm. Graphene addition to the modified composites in combination with natural fibres showed promising results in enhancing the mechanical properties under study. Moreover, graphene-modified composites exhibited higher thermal resistance compared to natural fibre reinforced composites. However, when nanofiller reinforcement exceeded a threshold value, the composites exhibited reduced flexural strength as a result of nanofiller agglomeration

A mouse model for triple-negative breast cancer tumor-initiating cells (TNBC-TICs) exhibits similar aggressive phenotype to the human disease

<p>Abstract</p> <p>Background</p> <p>Triple-negative breast cancer (TNBC) exhibit characteristics quite distinct from other kinds of breast cancer, presenting as an aggressive disease--recurring and metastasizing more often than other kinds of breast cancer, without tumor-specific treatment options and accounts for 15% of all types of breast cancer with higher percentages in premenopausal African-American and Hispanic women. The reason for this aggressive phenotype is currently the focus of intensive research. However, progress is hampered by the lack of suitable TNBC cell model systems.</p> <p>Methods</p> <p>To understand the mechanistic basis for the aggressiveness of TNBC, we produced a stable TNBC cell line by sorting for 4T1 cells that do not express the estrogen receptor (ER), progesterone receptor (PgR) or the gene for human epidermal growth factor receptor 2 (HER2). As a control, we produced a stable triple-positive breast cancer (TPBC) cell line by transfecting 4T1 cells with rat HER2, ER and PgR genes and sorted for cells with high expression of ER and PgR by flow cytometry and high expression of the HER2 gene by Western blot analysis.</p> <p>Results</p> <p>We isolated tumor-initiating cells (TICs) by sorting for CD24⁺/CD44^high/ALDH1⁺cells from TNBC (TNBC-TICs) and TPBC (TPBC-TICs) stable cell lines. Limiting dilution transplantation experiments revealed that CD24⁺/CD44^high/ALDH1⁺cells derived from TNBC (TNBC-TICs) and TPBC (TPBC-TICs) were significantly more effective at repopulating the mammary glands of naïve female BALB/c mice than CD24^-/CD44^-/ALDH1^-cells. Implantation of the TNBC-TICs resulted in significantly larger tumors, which metastasized to the lungs to a significantly greater extent than TNBC, TPBC-TICs, TPBC or parental 4T1 cells. We further demonstrated that the increased aggressiveness of TNBC-TICs correlates with the presence of high levels of mouse twenty-five kDa heat shock protein (Hsp25/mouse HspB1) and seventy-two kDa heat shock protein (Hsp72/HspA1A).</p> <p>Conclusions</p> <p>Taken together, we have developed a TNBC-TICs model system based on the 4T1 cells which is a very useful metastasis model with the advantage of being able to be transplanted into immune competent recipients. Our data demonstrates that the TNBC-TICs model system could be a useful tool for studies on the pathogenesis and therapeutic treatment for TNBC.</p

Zkoumání účinku žulového odpadního prášku jako pojiva pro různé molarity geopolymerního betonu na čerstvost a mechanické vlastnosti

Geopolymer concrete (GPC) is a novel alternative building material. The current study uses industrial waste as a binding agent to produce composite materials such as GPC. The impact of granite waste powder on geopolymer fresh and mechanical characteristics at 12, 16, and 20 M molarity is investigated. The current research paper also reveals the embodied energy parameter performances of GPC. The GPC-N series uses less energy and emits less CO2 compared with conventional concrete. At ambient curing conditions, the GPC-04-2 mix shows superior results than other series in fresh and hardened characteristics.Geopolymerní beton (GPC) je nový alternativní stavební materiál. Tato studie využívá průmyslový odpad jako pojivo pro výrobu kompozitních materiálů, jako je GPC. Je zkoumán vliv žulového odpadu na čerstvost geopolymeru a mechanické vlastnosti při molaritě 12, 16 a 20 M. Aktuální výzkumná zpráva také zjišťuje příslušné výkony energetických parametrů GPC. Řada GPC-N využívá méně energie a emituje méně CO2 než běžný beton. Při okolních podmínkách vytvrzování vykazuje směs GPC-04-2 lepší výsledky než jiné série v čerstvosti a vytvrzování

Hodnocení strukturálních vlastností geopolymerního betonu na bázi metakaolinu

Last few decades, there has been a substantial advancement of geopolymer (GP) as a Portland cement substitute. It is vital to investigate potential building uses for geopolymer concrete (GPC). Six different mixes were cast for an alkaline to binder (A/B) ratio of 0.25-0.50 with an interval of 0.05. Metakaolin-based geopolymer were cured at ambient tem-perature and tested for 7, 14, 28, and 90 days. Metakaolin-Marble (MM00) mix was observed to have a maximum slump. For an A/B ratio of 0.35, maximum compressive, split tensile, flexural strength and modulus of elasticity was achieved. For elevated temperature resis-tance, geopolymer concrete cubes were exposed to temperatures (T) of 200, 400, to 600 C. As the temperature increased, compressive strength (CS) reduced. As the increase of the alkaline to binder (A/B) ratio, the strength of geopolymer concrete increases up to a specific limit beyond the limit strength decline. An empirical formula for split tensile (STS) value prediction using compressive strength values is proposed, valid for determining split tensile strength value. The correlation between compressive strength, split tensile strength, flexural strength, and bulk density varies linearly for a quadratic polynomial.(c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).V posledních několika desetiletích došlo k podstatnému rozvoji geopolymeru (GP) jako náhrady portlandského cementu. Je nezbytné prozkoumat potenciální využití geopolymerního betonu (GPC) ve stavebnictví. Bylo odlito šest různých směsí pro poměr alkálie k pojivu (A/B) 0,25-0,50 s intervalem 0,05. Geopolymer na bázi metakaolinu byl vytvrzen při okolní teplotě a testován po dobu 7, 14, 28 a 90 dnů. Bylo pozorováno, že směs metakaolin-mramor (MM00) má maximální propad. Pro poměr A/B 0,35 bylo dosaženo maximálního tlaku, pevnosti v tahu, pevnosti v ohybu a modulu pružnosti. Pro zvýšenou teplotní odolnost byly geopolymerní betonové kostky vystaveny teplotám (T) 200, 400 až 600 C. Se zvyšující se teplotou se snižovala pevnost v tlaku (CS). Se vzrůstajícím poměrem zásaditosti k pojivu (A/B) se pevnost geopolymerního betonu zvyšuje až ke specifické hranici nad mezní pokles pevnosti. Je navržen empirický vzorec pro predikci hodnoty dělené pevnosti v tahu (STS) pomocí hodnot pevnosti v tlaku, platný pro stanovení hodnoty dělené pevnosti v tahu. Korelace mezi pevností v tlaku, pevností v tahu, pevností v ohybu a objemovou hmotností se pro kvadratický polynom mění lineárně.(c) 2022 The Author(s). Vydal Elsevier B.V. Toto je článek s otevřeným přístupem pod licencí CC BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/4.0/)