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151.
Pandey Divya Neekhra Bharat Mishra Meeta Banerjee Smita Jain Subodh Kumar 《Proceedings of the National Academy of Sciences, India. Section B.》2015,85(2):663-671
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Random amplified polymorphic DNA-PCR (RAPD-PCR) analysis was used in combination with morphological... 相似文献
152.
Banerjee S Smallwood A Moorhead J Chambers AE Papageorghiou A Campbell S Nicolaides K 《The Journal of clinical endocrinology and metabolism》2005,90(2):944-952
The inability of the mother to switch from T helper cell type 1 (Th1) to Th2 cytokine profiles at the fetal-maternal interface has been proposed as one of the primary causes of miscarriage, intrauterine growth restriction (IUGR), and preeclampsia (PE). The Th1 [interferon-gamma (IFN-gamma), TNF-alpha, and IL-12] and Th2 (IL-4 and IL-10) cytokines have opposite effects on human pregnancy. Leukemia inhibitory factor (LIF) promotes embryo implantation and sustains pregnancy, whereas IFN-gamma and TNF-alpha are detrimental to pregnancy. Both IFN-gamma and LIF are produced by maternal cells and tissues at the fetal-maternal interface, whereas the IFN-gamma receptors (IFN-gamma R1 and IFN-gamma R2) and LIF receptor are abundantly expressed on the surface of placental trophoblasts. The effect of IFN-gamma on T lymphocyte activation is influenced by the relative membrane density of its two receptors, particularly IFN-gamma R2. In this study we report that in PE (25-40 wk gestation) and PE complicated by IUGR, IFN-gamma R2 protein expression is severely down-regulated and is similar to that observed in early placenta (7-10 wk gestation) developing under low O(2) tension. IFN-gamma production was found to be inversely related to the IFN-gamma R2 protein expression, and LIF receptor protein expression in PE mimicked that in early placental development. These results show that in PE, placental trophoblasts fail to establish an early to late switch with respect to IFN-gamma and IFN-gamma R2 expression. This supports the hypothesis that trophoblasts control the polarization of maternal immune effectors and cytokine profiles at the fetal-maternal interface that could be subject to oxidative stress in PE. 相似文献
153.
154.
BACKGROUNDBiliary dilation is frequently related to obstruction; however, non-obstructive factors such as age and previous cholecystectomy have also been reported. In the past two decades there has been a dramatic increase in opiate use/dependence and utilization of cross-sectional abdominal imaging, with increased detection of biliary dilation, particularly in patients who use opiates.AIMTo evaluate associations between opiate use, age, cholecystectomy status, ethnicity, gender, and body mass index utilizing our institution’s integrated informatics platform. METHODSOne thousand six hundred and eighty-five patients (20% sample) presenting to our Emergency Department for all causes over a 5-year period (2011-2016) who had undergone cross-sectional abdominal imaging and had normal total bilirubin were included and analyzed.RESULTSCommon bile duct (CBD) diameter was significantly higher in opiate users compared to non-opiate users (8.67 mm vs 7.24 mm, P < 0.001) and in patients with a history of cholecystectomy compared to those with an intact gallbladder (8.98 vs 6.72, P < 0.001). For patients with an intact gallbladder who did not use opiates (n = 432), increasing age did not predict CBD diameter (r2 = 0.159, P = 0.873). Height weakly predicted CBD diameter (r2 = 0.561, P = 0.018), but weight, body mass index, ethnicity and gender did not.CONCLUSIONOpiate use and a history of cholecystectomy are associated with CBD dilation in the absence of an obstructive process. Age alone is not associated with increased CBD diameter. These findings suggest that factors such as opiate use and history of cholecystectomy may underlie the previously-reported association of advancing age with increased CBD diameter. Further prospective study is warranted. 相似文献
155.
Paramita Chakraborty Satyajit Das Kaushik Banerjee Abhinaba Sinha Susmita Roy Mitali Chatterjee 《Immunopharmacology and immunotoxicology》2014,36(2):165-175
Myeloid-derived suppressor cells (MDSCs), one of the major orchestrators of immunosuppressive network are present in the tumor microenvironment suppress antitumor immunity by subverting Th1 response in tumor site and considered as a great obstacle for advancement of different cancer immunotherapeutic protocols. Till date, various pharmacological approaches have been explored to modulate the suppressive functions of MDSCs in vivo. The present study describes our endeavor to explore a possibility of eradicating MDSCs by the application of a copper chelate, namely copper N-(2-hydroxy acetophenone) glycinate (CuNG), previously found to be a potential immunomodulator that can elicit antitumorogenic Th1 response in doxorubicin-resistant EAC (EAC/Dox) bearing mice. Herein, we demonstrated that CuNG treatment could reduce Gr-1+CD11b+ MDSC accumulation in ascitic fluid and spleen of EAC/Dox tumor model. Furthermore, we found that CuNG mediated reduction in MDSCs is associated with induction of Th1 response and reduction in Treg cells. Moreover, we observed that CuNG could deplete MDSCs by inducing Fas-FasL mediated apoptotic cell death where death receptor Fas expression is enhanced in MDSCs and FasL is provided by activated T cells. However, MDSC expansion from bone marrow cells and their differentiation was not affected by CuNG. Altogether, these findings suggest that the immunomodulatory property of CuNG is attributed to, at least in part, by its selective cytotoxic action on MDSCs. So, this preclinical study unveils a new mechanism of regulating MDSC levels in drug-resistant cancer model and holds promise of translating the findings into clinical settings. 相似文献
156.
Trimurti L. Lambat Ratiram G. Chaudhary Ahmed A. Abdala Raghvendra Kumar Mishra Sami H. Mahmood Subhash Banerjee 《RSC advances》2019,9(54):31683
A protocol for the efficient synthesis of arylbenzodioxy xanthenedione scaffolds was developed via a one-pot multi-component reaction of aromatic aldehydes, 2-hydroxy-1,4-naphthoquinone, and 3,4-methylenedioxy phenol using mesoporous PbO nanoparticles (NPs) as a catalyst under ball milling conditions. The synthesis protocol offers outstanding advantages, including short reaction time (60 min), excellent yields of the products (92–97%), solvent-free conditions, use of mild and reusable PbO NPs as a catalyst, simple purification of the products by recrystallization, and finally, the use of a green process of dry ball milling.An efficient one-pot multicomponent protocol was developed for the synthesis of arylbenzodioxy xanthenedione scaffolds using mesoporous PbO nanoparticles as reusable catalyst under solvent-free ball milling conditions.Recently, the ball milling technique has received great attention as an environmentally benign strategy in the context of green organic synthesis.1a The process of “ball milling” has been developed by adding mechanical grinding to the mixer or shaker mills. The ball milling generates a mechanochemical energy, which promotes the rupture and formation of the chemical bonds in organic transformations.1b Subsequently, detailed literature1c and books on this novel matter have been published.2a,b Several typical examples include carbon–carbon and carbon–heteroatom bond formation,2c organocatalytic reactions,2d oxidation by using solid oxidants,2e dehydrogenative coupling, asymmetric, and peptide or polymeric material synthesis, which have been reported under ball milling conditions.2e Hence, the organic reactions using ball milling activation carried out under neat reaction environments, exhibit major advantages,2f including short reaction time, lower energy consumption, quantitatively high yields and superior safety with the prospective for more improvement than the additional solvent-free conditions and clear-cut work-up.3–5On the other hand, the organic transformations using metal and metal oxide nanoparticles6 are attracting enormous interest due to the unique and interesting properties of the NPs.7,8,9a Particularly, PbO NPs9b provide higher selectivity in some organic reactions9c and find applications in various organic reactions, like Paal–Knorr reaction,10 synthesis of diethyl carbonate,11 phthalazinediones,12 disproportionation of methyl phenyl carbonate to synthesize diphenyl carbonate,13 the capping agent in organic synthesis, and selective conversion of methanol to propylene.14 In addition, the PbO NPs are also used in many industrial materials.15,16However, till date, PbO NPs have not been explored in MCRs leading to biologically important scaffolds. Among others, the xanthene scaffolds17 are one of the important heterocyclic compounds18 and are extensively used as dyes, fluorescent ingredients for visual imaging of the bio-molecules, and in optical device technology because of their valuable chemical properties.19 The xanthene molecules have conjointly been expressed for their antibacterial activity,20 photodynamic medical care, anti-inflammatory drug impact, and antiviral activity. Because of their various applications, the synthesis of these compounds has received a great deal of attention.21 Similarly, vitamin K nucleus22,23 shows a broad spectrum of biological properties, like anti-inflammatory, antiviral, antiproliferative, antifungal, antibiotic, and antipyretic.24a As a consequence, a variety of strategies24b have been demonstrated in the literature for the synthesis of xanthenes and their keto derivatives, like rhodomyrtosone-B,25a rhodomyrtosone-I,25b and BF-6 25c as well as their connected bioactive moieties. Few biologically active xanthene scaffolds are shown in (Fig. 1).Open in a separate windowFig. 1Some biologically important xanthenes and their keto derivatives.Due to the significance of these compounds, the synthesis of xanthenes and their keto derivatives using green protocols is highly desirable. Reported studies reveal that these scaffolds are synthesized by three-component condensations using p-TSA26 and scolecite27 as catalysts. However, these methods suffer from the use of toxic acidic catalysts like p-TSA, long reaction times (3 h), harsh refluxing26 or microwave reaction conditions,27 and tedious work-up procedures. The previously reported methods for the synthesis of xanthenediones are shown in Scheme 1.Open in a separate windowScheme 1Previous protocol for the synthesis of xanthenedione derivatives.Herein, we report an economical and facile multicomponent protocol, using ball milling, for the synthesis of 7-aryl-6H-benzo[H][1,3]dioxolo[4,5-b]xanthene-5,6(7H)-dione using PbO NPs as a heterogeneous catalyst (Scheme 2). The PbO NPs are non-corrosive, inexpensive, and easily accessible.Open in a separate windowScheme 2General reaction scheme of PbO NP-catalyzed synthesis of the xanthenedione scaffolds under ball milling conditions.In our protocol,28 the PbO NPs were initially prepared by mixing sodium dodecyl sulphate (2.5 mmol) and sodium hydroxide (10 mL, 0.1 N) with an aqueous methanolic solution of lead nitrate (2 mmol) under magnetic stirring at 30 °C by continuing the reaction for 2 h. Then, the obtained white polycrystalline product was filtered, washed with H2O, and dried at 120 °C, followed by calcination at 650 °C for 2 h. During this step, the white PbO NPs turned pale yellow in colour. Eventually, the synthesized PbO was then characterized by spectroscopic and analytical techniques.The powder X-ray diffraction (XRD) pattern revealed the crystalline nature of the PbO NPs as the diffraction peaks corresponding to (131), (311), (222), (022), (210), (200), (002), and (111) crystal planes were identified (Fig. 2). The XRD outline of the synthesized PbO NPs was further established for the formation of space group Pca21 29 with a single orthorhombic structure (JCPDS card number 76-1796). The sharp diffraction peaks indicated good crystallinity, and the average particle size of the PbO NPs was estimated to be 69 nm, as calculated using the Debye–Scherer equation.Open in a separate windowFig. 2The powder XRD pattern of PbO NPs.The surface morphology of the PbO NPs was analyzed by scanning electron microscopy (SEM), and the SEM image revealed the discrete and spongy appearance of the PbO NPs (Fig. 3).Open in a separate windowFig. 3The SEM image of PbO NPs.Moreover, the elemental composition obtained from energy dispersive X-ray (EDX) analysis confirmed that the material contains Pb and O elements, and no other impurity was present (Fig. 4).Open in a separate windowFig. 4The EDAX spectrum of crystalline PbO NPs.The transmission electron microscopy (TEM) image shown in Fig. 5 indicated the formation of orthorhombic crystallites of PbO with several hexagon-shaped particles. The dark spot in the TEM micrograph further confirmed the synthesis of PbO NPs, as the selected area diffraction pattern associated with such spots reveals the occurrence of the PbO NPs in total agreement with the X-ray diffraction data (Fig. 6). The average size of the PbO nanocrystals by TEM was approximated to be around 20 nm.Open in a separate windowFig. 5The TEM image of nanocrystalline PbO NPs.Open in a separate windowFig. 6The SAED image of nanocrystalline PbO NPs.The Fourier transform infrared (FT-IR) spectrum (ESI, S6†) of the PbO NPs displayed peaks at 575, 641, and 848 cm−1, which corresponds to the Pb–O vibrations. Furthermore, the absorption band at ∼3315 cm−1 was due to the presence of the hydroxyl group (–OH) in the NPs.The N2 adsorption–desorption isotherms of the PbO nanoparticles shown in Fig. 7 was consistent with type IV adsorption–desorption isotherms with H1 hysteresis corresponding to the cylindrical mesoporous structure. Moreover, the surface area, pore-volume, and BJH pore diameter were found to be 32.0 m2 g−1, 0.023 cm3 g−1, and 30.9 Å, respectively.Open in a separate windowFig. 7BET surface area and pore size of nanocrystalline PbO catalyst.The catalytic activity of the synthesized PbO NPs was tested in a one-pot multicomponent synthesis of arylbenzodioxoloyl xanthenedione derivative under ball milling condition according to the reaction scheme 2a, with 3,4-dimethoxybenzaldehyde (166.2 mg, 1.0 mmol), 3,4-methylenedioxyphenol (138.0 mg, 1.0 mmol), and 2-hydroxy-1,4-naphthoquinone (174.0 mg, 1.0 mmol) as reactants. The reaction conditions, the ball milling parameters (speed, time, and ball to solids ratio), and the PbO nanocatalyst amount were first optimized to produce the highest yield using experimental design as shown in Entry Conditions Rotation (rpm) Catalyst (mol%) Time (min) Yield (%)a 1 Ball milling 400 00 50 21 2 Ball milling 400 10 50 48 3 Ball milling 400 15 60 54 4 Ball milling 400 20 70 59 5 Ball milling 500 10 50 62 6 Ball milling 500 15 50 65 7 Ball milling 500 20 60 67 8 Ball milling 600 10 70 71 9 Ball milling 600 15 50 77 10 Ball milling 600 20 60 82 11 Ball milling 600 05 70 90 12 Ball milling 600 10 50 91 13 Ball milling b 600 15 60 97 14 Ball milling 600 20 70 97 15 No ball millingc — 15 60 —