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61.
Tyagi Vinay Kumar Ali Muntjeer Tawfik Ahmed Maharjan Namita Kazmi A. A. Okubo Tsutomu Harada Hideki 《Reviews in Environmental Science and Biotechnology》2021,20(2):389-418
Reviews in Environmental Science and Bio/Technology - The down-flow hanging sponge (DHS) process has been rigorously studied as a significant post-treatment of anaerobically pretreated sewage and... 相似文献
62.
Antimicrobial mechanism of resveratrol‐trans‐dihydrodimer produced from peroxidase‐catalyzed oxidation of resveratrol 下载免费PDF全文
63.
Leslie Michels Thompson Charity T. Aiken Linda S. Kaltenbach Namita Agrawal Katalin Illes Ali Khoshnan Marta Martinez-Vincente Montserrat Arrasate Jacqueline Gire O'Rourke Hasan Khashwji Tamas Lukacsovich Ya-Zhen Zhu Alice L. Lau Ashish Massey Michael R. Hayden Scott O. Zeitlin Steven Finkbeiner Kim N. Green Frank M. LaFerla Gillian Bates Lan Huang Paul H. Patterson Donald C. Lo Ana Maria Cuervo J. Lawrence Marsh Joan S. Steffan 《The Journal of cell biology》2009,187(7):1083-1099
Expansion of the polyglutamine repeat within the protein Huntingtin (Htt) causes Huntington''s disease, a neurodegenerative disease associated with aging and the accumulation of mutant Htt in diseased neurons. Understanding the mechanisms that influence Htt cellular degradation may target treatments designed to activate mutant Htt clearance pathways. We find that Htt is phosphorylated by the inflammatory kinase IKK, enhancing its normal clearance by the proteasome and lysosome. Phosphorylation of Htt regulates additional post-translational modifications, including Htt ubiquitination, SUMOylation, and acetylation, and increases Htt nuclear localization, cleavage, and clearance mediated by lysosomal-associated membrane protein 2A and Hsc70. We propose that IKK activates mutant Htt clearance until an age-related loss of proteasome/lysosome function promotes accumulation of toxic post-translationally modified mutant Htt. Thus, IKK activation may modulate mutant Htt neurotoxicity depending on the cell''s ability to degrade the modified species. 相似文献
64.
The response of the regressed seminal vesicles of 136- and 102-day hypophysectomized catfish to 30-day treatment with various steroids has been studied. Hypophysectomy results in complete regression of the seminal vesicles within 40 days. Of the various andro gens tested, ethynyltestosterone and 17 α-methyltestosterone are equipotent in producing weight increment and initiation of secretory activity in the regressed seminal vesicles but are 2.5 times more potent than testosterone propionate. Olive oil, eslradiol benzoate and desoxycorticosterone acetate treatment induce neither secretory activity nor weight increments in the regressed seminal vesicles. The adrenal androgens, 4-androstenedione and dehydroepiandrosterone proved to be weak androgens. The data indicate that only androgens can restore secretory activity in the regressed seminal vesicles of the hypophy sectomized catfish. 相似文献
65.
Dinesh Varshney Swati Bhatnagar Meenu Varshney Namita Singh 《Molecular simulation》2015,41(14):1193-1199
A theoretical analysis of specific heat C(T) behaviour of the Mg1 ? xAlxB2 (0 < x < 0.2) in the temperature domain 0 ≤ T ≤ 300 K is presented. Calculations of C(T) have been made within the two-component scheme: one is the phonon and the other is the electronic contribution. Phonon specific heat is well estimated from the Debye and Einstein temperature for Mg1 ? xAlxB2 obtained following an overlap repulsive potential. The interatomic potential of this model includes contributions from the long-range Coulomb attraction and the short-range overlap repulsion and the van der Waals attraction. The fermion constituent as the electronic specific heat is deduced using a suitable trial function above and below Tc. At the critical temperature, the discontinuity in specific heat is higher than that of other samples and the transition is sharper than for most samples. The theoretical results from boson and fermion terms are then compared with the experimental results. 相似文献
66.
Surface grafting of liposomes with the wide variety of ligands including antibodies and other proteins is a promising approach for targeted delivery of therapeutics. In this paper, we describe a simple method of synthesizing a hydrazine-functionalized poly(ethylene glycol)-phosphatidylethanolamine (PEG-PE)-based amphiphilic polymer which can conjugate a variety of ligands via a reversible, pH-cleavable bond. In this method, the targeting ligand is attached to the distal end of the PEG chain, which facilitates its easy access to the targeted site of interaction. The reversible attachment of targeting ligands is useful especially in multifunctional liposomal systems, whereafter successfully performing the function of targeting to the specific site, the bulky ligands, such as proteins or antibodies, are cleaved off in response to an environmental stimulus to expose some other functionalities such as ligands for intracellular penetration or organelle-specific targeting. To investigate the applicability of the protocol, the model ligands monoclonal antinucleosome antibody 2C5 and antimyosin antibody 2G4, and glycoproteins concanavalin A (Con-A) and avidin were conjugated to the synthesized polymer and incorporated into liposomes. In vitro assays including biochemical, enzyme-linked immunosorbent, fluorescence microscopy, and flow cytometry were used to confirm three key characteristics of the modified and/or liposome-attached proteins: successful conjugation of the targeting ligands to the polymer, preservation of specific activity of the ligands after the conjugation and liposome attachment, and the facile pH-sensitive ligand detachment. Monoclonal antibody 2C5 and 2G4, immobilized on the liposome surface, retained their binding affinity to corresponding antigens as confirmed by ELISA. The Con A-bearing liposomes showed significantly higher agglutination in the presence of its substrate mannan compared to plain liposomes (PL) and avidin-functionalized liposomes bound specifically with biotin-agarose. The study on the pH-dependence showed that almost 80% of the hydrazone bond was cleaved after rather brief preincubation of the immunoliposomes at pH 5 for 0.5 to 1 h. Fluorescence microscopy and flow cytometry analysis of cancer cells (HeLa and MCF-7) treated with cancer cell-specific targeting ligand mAb 2C5-bearing liposomes showed enhanced cellular binding. Studies at low pH clearly confirmed the easy cleavability of the targeting ligand from the liposomes resulting in significantly less or virtually no cellular association. 相似文献
67.
Nayyar Iqbal Marion L. Vetter Reneé H. Moore Jesse L. Chittams Cornelia V. Dalton‐Bakes Monique Dowd Catherine Williams‐Smith Serena Cardillo Thomas A. Wadden 《Obesity (Silver Spring, Md.)》2010,18(9):1733-1738
Low‐carbohydrate diets have been associated with significant reductions in weight and HbA1c in obese, diabetic participants who received high‐intensity lifestyle modification for 6 or 12 months. This investigation sought to determine whether comparable results to those of short‐term, intensive interventions could be achieved over a 24‐month study period using a low‐intensity intervention that approximates what is feasible in outpatient practice. A total of 144 obese, diabetic participants were randomly assigned to a low‐carbohydrate diet (<30 g/day) or to a low fat diet (≤30% of calories from fat with a deficit of 500 kcal/day). Participants were provided weekly group nutrition education sessions for the first month, and monthly sessions thereafter through the end of 24 months. Weight, HbA1c, glucose, and lipids were measured at baseline and 6, 12, and 24 months. Of the 144 enrolled participants, 68 returned for the month 24 assessment visit. Weights were retrieved from electronic medical records for an additional 57 participants (total, 125 participants) at month 24. All participants with a baseline measurement and at least one of the three other measurements were included in the mixed‐model analyses (n = 138). The low‐intensity intervention resulted in modest weight loss in both groups at month 24. At this time, participants in the low‐carbohydrate group lost 1.5 kg, compared to 0.2 kg in the low‐fat group (P = 0.147). Lipids, glycemic indexes, and dietary intake did not differ between groups at month 24 (or at months 6 or 12) (ClinicalTrials.gov number, NCT00108459). 相似文献
68.
The effects of three organophosphate pesticides, i.e. monocrotophos, dichlorvos, and phosphamidon on respiration in rat brain and liver tissue slices have been studied. Among these pesticides dichlorvos causes significant inhibition of respiration both in brain and liver. 相似文献
69.
High-resolution analysis of Y-chromosomal polymorphisms reveals signatures of population movements from central Asia and West Asia into India 总被引:6,自引:0,他引:6
Linguistic evidence suggests that West Asia and Central Asia have been the two major geographical sources of genes in the
contemporary Indian gene pool. To test the nature and extent of similarities in the gene pools of these regions we have collected
DNA samples from four ethnic populations of northern India, and have screened these samples for a set of 18 Y-chromosome polymorphic
markers (12 unique event polymorphisms and six short tandem repeats). These data from Indian populations have been analysed
in conjunction with published data from several West Asian and Central Asian populations. Our analyses have revealed traces
of population movement from Central Asia and West Asia into India. Two haplogroups, HG-3 and HG-9, which are known to have
arisen in the Central Asian region, are found in reasonably high frequencies (41.7% and 14.3% respectively) in the study populations.
The ages estimated for these two haplogroups are less in the Indian populations than those estimated from data on Middle Eastern
populations. A neighbour-joining tree based on Y-haplogroup frequencies shows that the North Indians are genetically placed
between the West Asian and Central Asian populations. This is consistent with gene flow from West Asia and Central Asia into
India. 相似文献
70.
Two nuclear receptors of xenobiotic drugs, PXR and CAR, are central regulators of detoxification enzymes. New studies extend the role of these receptors to a natural detoxification process. They coordinate induction of proteins for storage, glucuronidation, and canalicular transport of bilirubin. 相似文献