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981.
Biodiesel production using heterogeneous catalysts 总被引:3,自引:0,他引:3
The production and use of biodiesel has seen a quantum jump in the recent past due to benefits associated with its ability to mitigate greenhouse gas (GHG). There are large number of commercial plants producing biodiesel by transesterification of vegetable oils and fats based on base catalyzed (caustic) homogeneous transesterification of oils. However, homogeneous process needs steps of glycerol separation, washings, very stringent and extremely low limits of Na, K, glycerides and moisture limits in biodiesel. Heterogeneous catalyzed production of biodiesel has emerged as a preferred route as it is environmentally benign needs no water washing and product separation is much easier. The present report is review of the progress made in development of heterogeneous catalysts suitable for biodiesel production. This review shall help in selection of suitable catalysts and the optimum conditions for biodiesel production. 相似文献
982.
Singh Jitender Sangwan Namrata Chauhan Arushi Sarma Phulen Prakash Ajay Medhi Bikash Avti Pramod K. 《Molecular and cellular biochemistry》2022,477(3):885-896
Molecular and Cellular Biochemistry - The American Cancer Society claims that breast cancer is the second most significant cause of cancer-related death, with over one million women diagnosed each... 相似文献
983.
Purpose
To elucidate the reliability of MRI as a non-invasive tool for assessing in vivo muscle health and pathological amelioration in response to Losartan (Angiotensin II Type 1 receptor blocker) in DyW mice (mouse model for Laminin-deficient Congenital Muscular Dystrophy Type 1A).Methods
Multiparametric MR quantifications along with histological/biochemical analyses were utilized to measure muscle volume and composition in untreated and Losartan-treated 7-week old DyW mice.Results
MRI shows that DyW mice have significantly less hind limb muscle volume and areas of hyperintensity that are absent in WT muscle. DyW mice also have significantly elevated muscle levels (suggestive of inflammation and edema). Muscle T2 returned to WT levels in response to Losartan treatment. When considering only muscle pixels without T2 elevation, DyW T2 levels are significantly lower than WT (suggestive of fibrosis) whereas Losartan-treated animals do not demonstrate this decrease in muscle T2. MRI measurements suggestive of elevated inflammation and fibrosis corroborate with increased Mac-1 positive cells as well as increased Picrosirius red staining/COL1a gene expression that is returned to WT levels in response to Losartan.Conclusions
MRI is sensitive to and tightly corresponds with pathological changes in DyW mice and thus is a viable and effective non-invasive tool for assessing pathological changes. 相似文献984.
Amy E. Medlock Mesafint T. Shiferaw Jason R. Marcero Ajay A. Vashisht James A. Wohlschlegel John D. Phillips Harry A. Dailey 《PloS one》2015,10(8)
Heme is an essential cofactor for most organisms and all metazoans. While the individual enzymes involved in synthesis and utilization of heme are fairly well known, less is known about the intracellular trafficking of porphyrins and heme, or regulation of heme biosynthesis via protein complexes. To better understand this process we have undertaken a study of macromolecular assemblies associated with heme synthesis. Herein we have utilized mass spectrometry with coimmunoprecipitation of tagged enzymes of the heme biosynthetic pathway in a developing erythroid cell culture model to identify putative protein partners. The validity of these data obtained in the tagged protein system is confirmed by normal porphyrin/heme production by the engineered cells. Data obtained are consistent with the presence of a mitochondrial heme metabolism complex which minimally consists of ferrochelatase, protoporphyrinogen oxidase and aminolevulinic acid synthase-2. Additional proteins involved in iron and intermediary metabolism as well as mitochondrial transporters were identified as potential partners in this complex. The data are consistent with the known location of protein components and support a model of transient protein-protein interactions within a dynamic protein complex. 相似文献
985.
Paresh Dave Bhavin Vadera Ajay M V Kumar Palanivel Chinnakali Bhavesh Modi Rajesh Solanki Pranav Patel Prakash Patel Kirit Pujara Pankaj Nimavat Amar Shah Sandeep Bharaswadkar Kiran Rade Malik Parmar Sreenivas Achuthan Nair 《PloS one》2015,10(4)
Background
Revised National TB Control Programme (RNTCP) in India recommends that all previously-treated TB (PT) patients are offered drug susceptibility testing (DST) at diagnosis, using rapid diagnostics and screened out for rifampicin resistance before being treated with standardized, eight-month, retreatment regimen. This is intended to improve the early diagnosis of rifampicin resistance and its appropriate management and improve the treatment outcomes among the rest of the patients. In this state-wide study from Gujarat, India, we assess proportion of PT patients underwent rapid DST at diagnosis and the impact of this intervention on their treatment outcomes.Methods
This is a retrospective cohort study involving review of electronic patient-records maintained routinely under RNTCP. All PT patients registered for treatment in Gujarat during January-June 2013 were included. Information on DST and treatment outcomes were extracted from ''presumptive DR-TB patient register'' and TB treatment register respectively. We performed a multivariate analysis to assess if getting tested is independently associated with unfavourable outcomes (death, loss-to-follow-up, failure, transfer out).Results
Of 5,829 PT patients, 5306(91%) were tested for drug susceptibility with rapid diagnostics. Overall, 71% (4,113) TB patients were successfully treated - 72% among tested versus 60% among non-tested. Patients who did not get tested at diagnosis had a 34% higher risk of unsuccessful outcomes as compared to those who got tested (aRR - 1.34; 95% CI 1.20-1.50) after adjusting for age, sex, HIV status and type of TB. Unfavourable outcomes (particularly failure and switched to category IV) were higher among INH-resistant patients (39%) as compared to INH-sensitive (29%).Conclusion
Offering DST at diagnosis improved the treatment outcomes among PT patients. However, even among tested, treatment outcomes remained suboptimal and were related to INH resistance and high loss-to-follow-up. These need to be addressed urgently for further progress. 相似文献986.
987.
Increased oxidative stress and lymphocyte apoptosis are a hallmark of the autoimmune disease systemic lupus erythematosus (SLE). However, the association between oxidative stress and T lymphocytes apoptosis has still to be elucidated in SLE. In order to appraise the interaction between oxidative stress and T lymphocyte apoptosis with the severity of disease, oxidative stress profile and T lymphocytes apoptosis were studied. Increased levels of ROS, MDA and CD4(+) lymphocyte apoptosis were positively associated with disease activity while decreased levels of GSH and percentage expression of CD4(+) lymphocyte were negatively associated with disease activity. The decrease in intracellular levels of GSH was negatively associated with T lymphocyte, CD4(+) lymphocyte, CD8(+) lymphocyte apoptosis and intracellular caspase-3 expression. The present study suggests that increased T lymphocyte sub-sets apoptosis may be mediated by decreased intracellular glutathione concentration and severity of disease might be enhanced together by over-production of ROS in SLE. 相似文献
988.
989.
The Australian desert ant Melophorus bagoti shows remarkable visual navigational skills relying on visual rather than on chemical cues during their foraging trips. M. bagoti ants travel individually through a visually cluttered environment guided by landmarks as well as by path integration. An examination of their visual system is hence of special interest and we address this here. Workers exhibit distinct size polymorphism and their eye and ocelli size increases with head size. The ants possess typical apposition eyes with about 420-590 ommatidia per eye, a horizontal visual field of approximately 150° and facet lens diameters between 8 and 19?μm, depending on body size, with frontal facets being largest. The average interommatidial angle Δ? is 3.7°, the average acceptance angle of the rhabdom Δρ(rh) is 2.9°, with average rhabdom diameter of 1.6?μm and the average lens blur at half-width Δρ(l) is 2.3°. With a Δρ(rh)/Δ? ratio of much less than 2, the eyes undersample the visual scene but provide high contrast, and surprising detail of the landmark panorama that has been shown to be used for navigation. 相似文献
990.
The aim of this study was to explore the association of MMP-2 (-1306 C/T and -168 G/T) and MMP-9 (-1562 C/T) promoter polymorphisms in oral submucous fibrosis (OSMF) and head and neck squamous cell carcinoma (HNSCC) cases. These SNP were genotyped by PCR-RFLP. Total of 1260 individuals were recruited, of which 412 OSMF, 422 HNSCC and 426 were controls. In HNSCC, MMP-2 (-1306 C/T) and MMP-9 (-1562C/T) polymorphism, T allele showed strong association (p < 0.00 and p < 0.01) as compared to healthy control respectively, but not in case of OSMF and showed significant association with increasing progression of clinico-pathological grading. We concluded that SNPs in the MMP-2 and -9 promoter region may be associated with susceptibility to HNSCC not in OSMF. 相似文献