<正>The control of Leishmania infection relies primarily on chemotherapy till date.Resistance to pentavalent antimonials,which have been the recommended drugs to treat cutaneous and visceral ...leishmaniasis,is now widespread in Indian subcontinents.New drug formulations like amphotericin B,its lipid formulations,and miltefosine have shown great efGcacy to treat leishmaniasis but their high cost and therapeutic complications limit their usefulness.In addition, irregular and inappropriate uses of these second line drugs in endemic regions like state of Bihar, India threaten resistance development in the parasite.In context to the limited drug options and unavailability of either preventive or prophylactic candidates,there is a pressing need to develop true antileishmanial drugs to reduce the disease burden of this debilitating endemic disease.Notwithstanding significant progress of leishmanial research during last few decades, identification and characterization of novel drugs and drug targets are far from satisfactory.This review will initially describe current drug regimens and later will provide an overview on few important biochemical and enzymatic machineries that could be utilized as putative drug targets for generation of true antileishmanial drugs.
Human serum albumin is the most abundant plasma protein, and it regulates diverse body functions. In patients with advanced and decompensated cirrhosis, serum albumin levels are low because of a ...reduction in the hepatocyte mass due to disease per se and multiple therapeutic interventions. Because of their oncotic and nononcotic properties, administration of human albumin solutions (HAS) have been found to be beneficial in patients undergoing large‐volume paracentesis or who have hepatorenal syndrome or spontaneous bacterial peritonitis. Albumin also improves the functionality of the immune cells and mitigates the severity and risk of infections in advanced cirrhosis. Its long‐term administration can modify the course of decompensated cirrhosis patients by reducing the onset of new complications, improving the quality of life, and probably providing survival benefits. There is, however, a need to rationalize the dose, duration, and frequency of albumin therapy in different liver diseases and stages of cirrhosis. In patients with acute‐on‐chronic liver failure, potentially toxic oxidized isoforms of albumin increase substantially, especially human nonmercaptalbumin and 2, and nitrosoalbumin. The role of administration of HAS in such patients is unclear. Determining whether removal of the pathological and dysfunctional albumin forms in these patients by “albumin dialysis” is helpful, requires additional studies. Use of albumin is not without adverse events. These mainly include allergic and transfusion reactions, volume overload, antibody formation and coagulation derangements. Considering their cost, limited availability, need for a health care setting for their administration, and potential adverse effects, judicious use of HAS in liver diseases is advocated. There is a need for new albumin molecules and economic alternatives in hepatologic practice.
Tight focusing of partially polarized vortex beams has been studied. Compact form of the coherence matrix has been derived for polarized vortex beams. Effects of topological charge and polarization ...distribution of the incident beam on intensity distribution, degree of polarization, and coherence have been investigated.
Key message
Reproductive stage salinity tolerance is most critical for rice as it determines the yield under stress. Few studies have been undertaken for this trait as phenotyping was cumbersome, but ...new methodology outlined in this review seeks to redress this deficiency. Sixty-three meta-QTLs, the most important genomic regions to target for enhancing salinity tolerance, are reported.
Although rice has been categorized as a salt-sensitive crop, it is not equally affected throughout its growth, being most sensitive at the seedling and reproductive stages. However, a very poor correlation exists between sensitivity at these two stages, which suggests that the effects of salt are determined by different mechanisms and sets of genes (QTLs) in seedlings and during flowering. Although tolerance at the reproductive stage is arguably the more important, as it translates directly into grain yield, more than 90% of publications on the effects of salinity on rice are limited to the seedling stage. Only a few studies have been conducted on tolerance at the reproductive stage, as phenotyping is cumbersome. In this review, we list the varieties of rice released for salinity tolerance traits, those being commercially cultivated in salt-affected soils and summarize phenotyping methodologies. Since further increases in tolerance are needed to maintain future productivity, we highlight work on phenotyping for salinity tolerance at the reproductive stage. We have constructed an exhaustive list of the 935 reported QTLs for salinity tolerance in rice at the seedling and reproductive stages. We illustrate the chromosome locations of 63 meta-QTLs (with 95% confidence interval) that indicate the most important genomic regions for salt tolerance in rice. Further study of these QTLs should enhance our understanding of salt tolerance in rice and, if targeted, will have the highest probability of success for marker-assisted selections.
Lignin is amorphous in nature, lacks stereoregularity, and is not susceptible to hydrolytic attack. Despite its resistant nature, it is however degraded by various microorganisms, particularly, ...white-rot fungi. Such fungi are capable of extracellular production of lignin peroxidase, manganese peroxidase, and laccase, the three major enzymes associated with ligninolysis. Though all white-rot fungi do not produce all the three enzymes, laccase occupies an important place in ligninolysis. Laccase belongs to a diverse group of enzymes called oxidoreductases and is also known as benzenediol: oxygen oxidoreductase. They have low substrate specificity. The copper-containing enzyme laccase has been detected in a variety of organisms such as bacteria, fungi, plants, and insects. Mostly, these are extracellular proteins, although intracellular laccases have also been detected in some fungi and insects. Fungal laccases are believed to play a variety of roles, such as, morphogenesis, pathogenesis, and lignin degradation. As an oxidase, laccase is used in many agricultural, industrial, and medicinal applications. Current investigations are focused on laccase-based biooxidation, biotransformation, biosensor, and enzymatic synthesis of organic compounds. By enhancing laccase production using different physiochemical parameters, better understanding of the mechanism for the reactions of interest, and optimizing the catalytic activity of laccase, it can be used in a better way in diverse fields of biotechnology.
for many decades, there has been a general perception in the literature that Fourier methods are not suitable for the analysis of nonlinear and non-stationary data. In this paper, we propose a novel ...and adaptive Fourier decomposition method (FDM), based on the Fourier theory, and demonstrate its efficacy for the analysis of nonlinear and non-stationary time series. The proposed FDM decomposes any data into a small number of ‘Fourier intrinsic band functions’ (FIBFs). The FDM presents a generalized Fourier expansion with variable amplitudes and variable frequencies of a time series by the Fourier method itself. We propose an idea of zero-phase filter bank-based multivariate FDM (MFDM), for the analysis of multivariate nonlinear and non-stationary time series, using the FDM. We also present an algorithm to obtain cut-off frequencies for MFDM. The proposed MFDM generates a finite number of band-limited multivariate FIBFs (MFIBFs). The MFDM preserves some intrinsic physical properties of the multivariate data, such as scale alignment, trend and instantaneous frequency. The proposed methods provide a time–frequency–energy (TFE) distribution that reveals the intrinsic structure of a data. Numerical computations and simulations have been carried out and comparison is made with the empirical mode decomposition algorithms.
•Fuel injection pressure & timings affect engine performance, emissions and combustion.•Rapid combustion, higher cylinder pressure & ROHR at advanced injection timings.•Superior performance at lower ...FIP giving lower BSFC & emissions, & higher BTE.•Emission characteristics improve with advanced fuel injection timings.•Particulate number concentration in a CI engine increases with increasing engine load.
For a diesel engine, fuel injection pressure (FIP) and injection timings are very important parameters, which influence the engine performance, emissions, and combustion. Other injection parameters affecting engine performance are rate of injection, injection pattern, number of injections etc. A single cylinder research engine was used to experimentally determine the effects of fuel injection strategies and injection timings on engine combustion, performance and emission characteristics. The experiments were conducted at constant speed (2500rpm) with two FIPs (500 and 1000bars respectively) and different start of injection (SOI) timings. Cylinder pressure and rate of heat release (ROHR) were found to be higher for lower FIPs however advanced injection timings gave higher ROHR in early combustion stages. Brake thermal efficiency (BTE) increased with increased injection pressures while exhaust gas temperature and brake mean effective pressure (BMEP) increased upto 500bars. These parameters reduced slightly with increase in FIP. For advanced SOI, BMEP and BTE increased, while brake specific fuel consumption (BSFC) and exhaust gas temperature reduced significantly. Carbon dioxide (CO2) and hydrocarbon (HC) emissions decreased however nitrogen oxide (NOx) emissions increased with increasing FIP. Lower CO2 and HC emissions, and significantly higher NOx emissions were observed with advanced injection timings. Particulate number–size distribution increased with increasing engine load however it reduced with increasing FIP.
Instantaneous synthesis of metal nanoparticles using tannic acid via green approach. This paper cites the different catalytic effect of metal nanoparticles for the degradation of methyl orange.
...Display omitted
▶ Metal nanoparticles (Ag, Au and Pt) of average diameter 10
nm have been synthesized via green approach. ▶ Degradation of methyl orange (MO) in presence of strong reducing agent such as NaBH
4 is extremely slow. ▶ Synthesized nanoparticles were used as a catalyst for the degradation of MO in presence of NaBH
4 and their rate constant (
k) is compared. ▶ Rate of degradation of MO follows the order:
k
Ag nanoparticles
≫
k
Au nanoparticles
>
kPt nanoparticles
≫
k
uncatalyzed reaction.
Gold, silver and platinum nanoparticles have been synthesized following a green approach by reducing the corresponding salt using tannic acid as reducing agent at room temperature in aqueous medium. The reaction is instantaneous and the average diameter of the particles formed is around 10
nm in all the three cases as measured by TEM. These nanoparticles have been used as a catalyst for the degradation of methyl orange in the presence of sodium borohydride (NaBH
4). Silver nanoparticles have a drastic catalytic effect as compared to gold or platinum nanoparticles on the degradation of methyl orange in the presence of sodium borohydride. From the kinetic data it is concluded that the rate constant follows the order:
k
Ag
nanoparticles
≫
k
Au
nanoparticles
>
k
Pt
nanoparticles
≫
k
uncatalyzed
reaction. The high catalytic effect of silver nanoparticles has been attributed to its low value of work function as compared to Au and Pt. The uncatalyzed reaction does not show any decrease in the absorbance value within the given experimental time due to the large kinetic barrier, i.e. high activation energy. Decrease in absorbance value for uncatalyzed reaction is observed after nearly 48
h that too at a very high concentration of reducing agent, thereby indicating that reaction is extremely slow and reduction of methyl orange is thermodynamically feasible.
Background
Alzheimer’s disease is a complex multifaceted neurodegenerative disorder. It is characterized by the deposition of extracellular amyloid senile plaques and intracellular neurofibrillary ...tangles leading to progressive dementia and death in aged adult population. Recent emerging research has highlighted a potential pharmacological role of 5-lipoxyenase-cysteinyl leukotriene pathway in molecular pathogenesis of Alzheimer’s disease.
Objective
Although cysteinyl leukotrienes and their receptors have a major clinical role in chronic respiratory inflammation, their roles in chronic neuroinflammation in Alzheimer’s disease need a detailed and careful exploration.
Results and conclusion
This review article highlights a novel role of cysteinyl leukotrienes and their receptors in pathophysiology of Alzheimer’s disease in order to understand the underlying molecular mechanism. In addition, it summarizes the recent advances in various pre-clinical and clinical strategies used to modulate this pathway for therapeutic targeting of Alzheimer’s disease.
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