同时检测玉米中黄曲霉毒素B1和赭曲霉毒素A的时间分辨荧光免疫层析试纸条的研制

研究制备了一种可同时快速定量检测黄曲霉毒素B1 (aflatoxin B1,AFB1)和赭曲霉毒素A(ochratoxin A,OTA)的二联时间分辨荧光免疫层析试纸条.采用铕系时间分辨荧光微球分别标记AFB1和OTA单克隆抗体,优化荧光微球活化pH值、标记的抗体浓度、荧光探针使用量、检测线包被原浓度、质控线羊抗鼠Ig...     

基于LabWindows/CVI火电厂球磨机控制系统监控软件的开发

基于多任务多线程的软件设计思想，采用面向仪器与测控过程的交互式C／C＋＋开发平台LabWindows/CVI5．5，针对火电厂球磨机模糊－神经元控制系统，进行了监控软件的研究与开发。     

An efficient one pot synthesis of water-dispersible calix[4]arene polyhydrazide protected gold nanoparticles--a "turn off" fluorescent sensor for Hg[II] ions

In the present study, we report the synthesis of aqueous stable gold nanoparticles by using calix[4]arene polyhydrazide (CPH) as both reducing and capping agents. The calix[4]arene polyhydrazide reduced gold nanoparticles (CPH-AuNps) were characterized by UV/Vis, particle size analyzer (PSA) and transmission electron mictroscopy (TEM). The records confirmed high stability of CPH-AuNps in aqueous solution over a long period of time and even at varied pH. Additionally, CPH-AuNps have been investigated for its application as "Turn Off" fluorescent sensor for Hg[II]. A concentration of Hg[II] in the limit of 10 nM to 10 microM can be detected based on fluorescence quenching of the CPH-AuNPs and it was also concluded from the spectroscopic data that CPH-AuNPs possess excellent selectivity to Hg[II] over several metal ions like Pb[II], Cu[II], Cd[II], Mn[II], Zn[II] and Ni[II].     

Development of nanoformulation of picroliv isolated from Picrorrhiza kurroa

Picroliv, a mixture of picroside I and kutkoside isolated from rhizome of Picrorrhiza kurroa has been reported for many pharmaceutical properties such as hepatoprotective, anticholestatic, antioxidant and immune‐modulating activity. However, picroliv possessed lesser efficacy due to its poor aqueous solubility and lesser bioavailability. To find solution, picroliv was loaded into biodegradable poly lactic acid nanoparticles (PLA NPs) using solvent evaporation method. The picroliv‐loaded PLA NPs were characterised by UV–vis spectroscopy, atomic force microscopy, transmission electron microscopy, Fourier transform infrared and Zeta sizer. The size of picroliv‐loaded PLA NPs was 182 ± 20 nm. Zeta potential of picroliv‐loaded PLA NPs was −23.5 mV, indicated their good stability. In vitro picroliv release from picroliv‐loaded PLA NPs showed an initial burst release followed by slow and sustained release. The efficacy of picroliv‐loaded PLA NPs was assessed against KB cell lines. Blank PLA NPs showed no cytotoxicity on KB cells. The picroliv‐loaded PLA NPs showed more cytotoxic activity on KB cells as compared to the pure drug. Hence, the developed picroliv nanoformulation would find potential application in pharma‐sector.Inspec keywords: drugs, nanomedicine, nanofabrication, biodegradable materials, nanoparticles, biomedical materials, evaporation, ultraviolet spectra, visible spectra, atomic force microscopy, transmission electron microscopy, Fourier transform infrared spectra, electrokinetic effects, drug delivery systems, cellular biophysics, toxicologyOther keywords: nanoformulation development, Picrorrhiza kurroa, picroside I‐kutkoside mixture, rhizome, pharmaceutical properties, hepatoprotective activity, anticholestatic activity, antioxidant activity, immune‐modulating activity, aqueous solubility, bioavailability, biodegradable poly lactic acid nanoparticles, solvent evaporation method, picroliv‐loaded PLA NPs, UV‐visible spectroscopy, atomic force microscopy, transmission electron microscopy, Fourier transform infrared spectra, zeta‐sizer, in vitro picroliv release, KB cell lines, initial burst release, cytotoxic activity, picroliv nanoformulation, pharma‐sector     

Expression of connexin 43 and gap junctional intercellular communication in the cumulus-oocyte complex in sheep

To evaluate the effects of FSH, LH and/or cAMP on expression of connexin 43 (Cx43) in the ovine cumulus-oocyte complex (COC) and gap junctional intercellular communication (GJIC) of cumulus cells, two experiments were carried out. In experiment 1, Cx43 was immunodetected in the COC, before or after maturation, obtained from non-treated or FSH-treated ewes. The expression of Cx43 in the COC was greater (P < 0.01) on day 16 than on day 15 of the estrous cycle. In vivo FSH treatment decreased (P < 0.02) Cx43 expression on day 16 but not on day 15 of the estrous cycle. In experiment 2, intact COCs or isolated cumulus cells obtained from small and large follicles from FSH-treated ewes were cultured with or without FSH, LH or cAMP agonist and evaluated for GJIC by laser cytometry. For large follicles, the basal rate of GJIC was greater (P < 0.01) for cumulus cells in intact COCs than for isolated cumulus cells. FSH increased (P < 0.04) GJIC in cumulus cells in intact COCs and tended to increase (P < 0.1) GJIC in isolated cumulus cells from small follicles but decreased (P < 0.01) GJIC in cumulus cells in intact COCs from large follicles. LH also increased (P < 0.01) GJIC in isolated cumulus cells from small follicles but decreased GJIC in intact COCs (P < 0.01) and isolated cumulus cells (P < 0.02) from large follicles. cAMP increased (P < 0.01) the GJIC in both intact COCs and cumulus cells from small and large follicles. These results indicate that day of estrous cycle, stage of maturation and duration of FSH treatment affect expression of Cx43 in ovine COCs. In intact COCs, GJIC in cumulus cells was enhanced, probably due to the presence of the oocyte. In addition, the effects of FSH and LH, but not cAMP, on GJIC of cumulus cells depended on the stage of follicular development and on the presence of the oocyte.     

Catalytic performance of sulfate-grafted graphene oxide for esterification of acetic acid with methanol

Graphene oxide possesses tremendous mechanical and electronic properties in combination with large surface area and accessible active sites leading to the development of novel innovative heterogeneous catalysts. The present study elaborates the catalytic activity of graphene oxide, enhanced by grafting active sulfate groups on its surface to result as a superior catalyst. The catalyst was evaluated in the model acetic acid esterification reaction with methanol in terms of acid conversion. Catalysts consisting of varied sulfate concentrations and calcination time were synthesized and optimized for its best catalytic activity. The prepared catalysts (GO-SO₄) were characterized using XRD, FT-IR, SEM-EDS, XPS, and BET. A 44% enhancement in catalyst activity was observed using sulfate-grafted graphene oxide (GO-SO₄) catalyst over bare GO due to the synergistic effect of sulfate ions. The catalyst can be separated out by simple filtration. Further, the influence of operating process parameters including catalyst loading, and the reaction temperature was evaluated toward the maximum acid conversion. In addition, the detailed kinetic study was also done in this system using Pseudo-homogeneous model.     

Expanding the Scope of Biocatalysis: Oxidative Biotransformations on Solid‐Supported Substrates

Oxidative biocatalytic reactions were performed on solid‐supported substrates, thus expanding the repertoire of biotransformations that can be carried out on the solid phase. Various phenylacetic and benzoic acid analogues were attached to controlled pore glass beads via an enzyme‐cleavable linker. Reactions catalyzed by peroxidases (soybean and chloro), tyrosinase, and alcohol oxidase/dehydrogenase gave a range of products, including oligophenols, halogenated aromatics, catechols, and aryl aldehydes. The resulting products were recovered following cleavage from the beads using α‐chymotrypsin to selectively hydrolyze a chemically non‐labile amide linkage. Controlled pore glass (CPG) modified with a polyethylene glycol (PEG) linker afforded substantially higher product yields than non‐PEGylated CPG or non‐swellable polymeric resins. This work represents the first attempt to combine solid‐phase oxidative biotransformations with subsequent protease‐catalyzed cleavage, and serves to further expand the use of biocatalysis in synthetic and medicinal chemistry.     

Interactions Between Tumor Biology and Targeted Nanoplatforms for Imaging Applications

Although considerable efforts have been conducted to diagnose, improve, and treat cancer in the past few decades, existing therapeutic options are insufficient, as mortality and morbidity rates remain high. Perhaps the best hope for substantial improvement lies in early detection. Recent advances in nanotechnology are expected to increase the current understanding of tumor biology, and will allow nanomaterials to be used for targeting and imaging both in vitro and in vivo experimental models. Owing to their intrinsic physicochemical characteristics, nanostructures (NSs) are valuable tools that have received much attention in nanoimaging. Consequently, rationally designed NSs have been successfully employed in cancer imaging for targeting cancer‐specific or cancer‐associated molecules and pathways. This review categorizes imaging and targeting approaches according to cancer type, and also highlights some new safe approaches involving membrane‐coated nanoparticles, tumor cell‐derived extracellular vesicles, circulating tumor cells, cell‐free DNAs, and cancer stem cells in the hope of developing more precise targeting and multifunctional nanotechnology‐based imaging probes in the future.     

Affordable housing finance companies in India: how do they ‘differently’ serve the underserved?

Abstract

Over the years, the importance of access to affordable finance has inevitably been recognized as a critical component of developing the third world. Against the backdrop of huge under-penetration of the housing finance sector in India, this study reflects on the functioning of Affordable Housing Finance Companies (AHFCs), which are among the important stakeholders providing affordable housing loans to the low-income segment households. However, the process through which these new entrants have been able to down-market housing finance remains a black box till date. In light of this research gap, this study proposes a conceptual model that succinctly captures the business process of AHFCs across three main dimensions: Outreach Approach, Lending and Underwriting Practices and Risk Management Interventions. This model reflects on the kaleidoscope of process innovations that the AHFCs have embraced to cater to the housing finance needs of the low-income customers, while achieving profitability and social impact.