Standardised Sonneratia apetala Buch.-Ham. fruit extract inhibits human neutrophil elastase and attenuates elastase-induced lung injury in mice

Chronic obstructive pulmonary disease (COPD) along with asthma is a major and increasing global health problem. Smoking contributes to about 80%–90% of total COPD cases in the world. COPD leads to the narrowing of small airways and destruction of lung tissue leading to emphysema primarily caused by neutrophil elastase. Neutrophil elastase plays an important role in disease progression in COPD patients and has emerged as an important target for drug discovery. Sonneratia apetala Buch.-Ham. is a mangrove plant belonging to family Sonneratiaceae. It is widely found in the Sundarban regions of India. While the fruits of this plant have antibacterial, antifungal, antioxidant and astringent activities, fruit and leaf extracts have been shown to reduce the symptoms of asthma and cough. The aim of this study is to find whether hydro alcoholic fruit extracts of S. apetala inhibit neutrophil elastase and thus prevent the progression of neutrophil elastase-driven lung emphysema. The hydroalcoholic extract, ethanol: water (90:10), of the S. apetala Buch.-Ham. fresh fruits (SAM) were used for neutrophil elastase enzyme kinetic assay and IC50 of the extract was determined. The novel HPLC method has been developed and the extract was standardized with gallic acid and ellagic acid as standards. The extract was further subjected to LC-MS2 profiling to identify key phytochemicals. The standardized SAM extract contains 53 μg/mg of gallic acid and 95 μg/mg of ellagic acid, based on the HPLC calibration curve. SAM also reversed the elastase-induced morphological change of human epithelial cells and prevented the release of ICAM-1 in vitro and an MTT assay was conducted to assess the viability. Further, 10 mg/kg SAM had reduced alveolar collapse induced by neutrophil elastase in the mice model. Thus, in this study, we reported for the first time that S. apetala fruit extract has the potential to inhibit human neutrophil elastase in vitro and in vivo

Stabilization of Brownmillerite-Type SrCoO2.5 by a Cost-Effective Quenching Method for Oxygen-Scavenging Applications

Brownmillerite (BM)-type oxide sorbents have gained attention recently for producing oxygen-enriched streams. Herein, a cost-effective method of quenching with the use of an Al foil pad is adapted for the synthesis of brownmillerite SrCoO2.5. The oxygen storage capacity of this oxide has been investigated using a simple home-built volumetric setup. The oxygen-rich phase was formed by a pressurized heat-treatment of a BM sample. The oxygen storage capacity of the sample has been calculated from the pressure change during desorption. The effect of oxygen pressure on the amount of oxygen stored inside the sample has also been evaluated. Furthermore, selective absorption of oxygen is confirmed by performing the absorption in compressed air. The results indicate that 15.28 cm(3) O-2 g(-1) can be stored in the sample at STP. The change in oxygen content in SrCoO2.5+delta varied reversibly up to a delta value of 0.26, which is confirmed by iodometric titration. It is shown that the new method of quenching proposed does not deteriorate the oxygen storage property of the material

Curcumin: the spicy modulator of breast carcinogenesis

Abstract Worldwide breast cancer is the most common cancer in women. For many years clinicians and the researchers are examining and exploring various therapeutic modalities for breast cancer. Yet the disease has remained unconquered and the quest for cure is still going on. Present-day strategy of breast cancer therapy and prevention is either combination of a number of drugs or a drug that modulates multiple targets. In this regard natural products are now becoming significant options. Curcumin exemplifies a promising natural anticancer agent for this purpose. This review primarily underscores the modulatory effect of curcumin on the cancer hallmarks. The focus is its anticancer effect in the complex pathways of breast carcinogenesis. Curcumin modulates breast carcinogenesis through its effect on cell cycle and proliferation, apoptosis, senescence, cancer spread and angiogenesis. Largely the NFkB, PI3K/Akt/mTOR, MAPK and JAK/STAT are the key signaling pathways involved. The review also highlights the curcumin mediated modulation of tumor microenvironment, cancer immunity, breast cancer stem cells and cancer related miRNAs. Using curcumin as a therapeutic and preventive agent in breast cancer is perplexed by its diverse biological activity, much of which remains inexplicable. The information reviewed here should point toward potential scope of future curcumin research in breast cancer

Particle size effect on the thermal conductivity reduction of silicon based thermoelectric composites

International audienceComposites of Si and transition metal silicides have been studied extensively for waste heat recovery applications because of their non-toxic, low cost and environmentally friendly nature. Composite samples made up of Si particles embedded in an Al doped b-FeSi 2 matrix are synthesized by eutectoid decomposition of a-Fe 2 Si 5Àx Al x (x ¼ 0.025, 0.05). The presence and uniform spatial distribution of Si particles are confirmed by means of X-ray diffraction and backscattered electron images of the samples, respectively. We measure the thermoelectric properties of our composite samples and find the highest figure of merit ZT ¼ 0.09 for the sample with x ¼ 0.05 at 773 K. Based on the interface thermal resistance predicted by the diffused mismatch model, it is shown that (i) the experimental values of the thermal conductivity of the composites are well described by the crowding factor model for different particles sizes and (ii) the matrix thermal conductivity can be reduced by half by inserting Si nanoparticles with a volume fraction of 50% and a radius of about 10 nm. Furthermore, a condition for lowering the thermal conductivity of particulate composites is derived, which can be useful to tune their microstructural parameters for thermoelectric applications

Room temperature synthesis of transition metal silicide-conducting polymer micro-composites for thermoelectric applications

Organic polymer thermoelectrics (TE) as well as transition metal (TM) silicides are two thermoelectric class of materials of interest because they are composed of atomic elements of high abundatice; which is a prerequisite for mass implementation of thermoelectric (TE) solutions for solar and waste heat recovery. But both materials have drawbacks when it comes to finding low-cost manufacturing. The metal silicide needs high temperature (amp;gt;1000 degrees C) for creating TE legs in a device from solid powder, but it is easy to achieve long TE legs in this case. On the contrary, organic TEs are synthesized at low temperature from solution. However, it is difficult to form long legs or thick films because of their low solubility. In this work, we propose a novel method for the room temperature synthesis of TE composite containing the microparticles of chromium disilicide; CrSi2 (inorganic filler) in an organic matrix of nanofibrillated cellulose-poly(3,4-ethyelenedioxythiophene)-polystyrene sulfonate (NFC-PEDOT:PSS). With this method, it is easy to create long TE legs in a room temperature process. The originality of the approach is the use of conducting polymer aerogel microparticles mixed with CrSi2 microparticles to obtain a composite solid at room temperature under pressure. We foresee that the method can be scaled up to fabricate and pattern TE modules. The composite has an electrical conductivity (sigma) of 5.4 +/- 0.5 S/cm and the Seebeck coefficient (a) of 88 +/- 9 mu V/K, power factor (alpha(2)sigma) of 4 +/- 1 mu Wm(-1) K-2 at room temperature. At a temperature difference of 32 degrees C, the output power/unit area drawn across the load, with the resistance same as the internal resistance of the device is 0.6 +/- 0.1 mu W/cm(2). (C) 2017 Elsevier B.V. All rights reserved.Funding Agencies|European Research Council [307596]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; "the Power Papers project" - Knut and Alice Wallenberg foundation; RISE - the Research Institutes of Sweden; University Grants Commission, India</p

Room temperature synthesis of transition metal silicide-conducting polymer micro-composites for thermoelectric applications

Organic polymer thermoelectrics (TE) as well as transition metal (TM) silicides are two thermoelectric class of materials of interest because they are composed of atomic elements of high abundatice; which is a prerequisite for mass implementation of thermoelectric (TE) solutions for solar and waste heat recovery. But both materials have drawbacks when it comes to finding low-cost manufacturing. The metal silicide needs high temperature (amp;gt;1000 degrees C) for creating TE legs in a device from solid powder, but it is easy to achieve long TE legs in this case. On the contrary, organic TEs are synthesized at low temperature from solution. However, it is difficult to form long legs or thick films because of their low solubility. In this work, we propose a novel method for the room temperature synthesis of TE composite containing the microparticles of chromium disilicide; CrSi2 (inorganic filler) in an organic matrix of nanofibrillated cellulose-poly(3,4-ethyelenedioxythiophene)-polystyrene sulfonate (NFC-PEDOT:PSS). With this method, it is easy to create long TE legs in a room temperature process. The originality of the approach is the use of conducting polymer aerogel microparticles mixed with CrSi2 microparticles to obtain a composite solid at room temperature under pressure. We foresee that the method can be scaled up to fabricate and pattern TE modules. The composite has an electrical conductivity (sigma) of 5.4 +/- 0.5 S/cm and the Seebeck coefficient (a) of 88 +/- 9 mu V/K, power factor (alpha(2)sigma) of 4 +/- 1 mu Wm(-1) K-2 at room temperature. At a temperature difference of 32 degrees C, the output power/unit area drawn across the load, with the resistance same as the internal resistance of the device is 0.6 +/- 0.1 mu W/cm(2). (C) 2017 Elsevier B.V. All rights reserved.Funding Agencies|European Research Council [307596]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; "the Power Papers project" - Knut and Alice Wallenberg foundation; RISE - the Research Institutes of Sweden; University Grants Commission, India</p