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101.
102.
Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are two fatal neurodegenerative disorders with considerable clinical, pathological and genetic overlap. Both disorders are characterized by the accumulation of pathological protein aggregates that contain a number of proteins, most notably TAR DNA binding protein 43?kDa (TDP-43). Surprisingly, recent clinical studies suggest that dyslipidemia, high body mass index, and type 2 diabetes mellitus are associated with better clinical outcomes in ALS. Moreover, ALS and FTLD patients have a significantly lower incidence of cardiovascular disease, supporting the idea that an unfavorable metabolic profile may be beneficial in ALS and FTLD. The two most widely studied ALS/FTLD models, super-oxide dismutase 1 (SOD1) and TAR DNA binding protein of 43 kDA (TDP-43), reveal metabolic dysfunction and a positive effect of metabolic strategies on disease onset and/or progression. In addition, molecular studies reveal a role for ALS/FTLD-associated proteins in the regulation of cellular and whole-body metabolism. Here, we systematically evaluate these observations and discuss how changes in cellular glucose/lipid metabolism may result in abnormal protein aggregations in ALS and FTLD, which may have important implications for new treatment strategies for ALS/FTLD and possibly other neurodegenerative conditions.  相似文献   
103.
Objective: To qualitative and quantitatively review published literature assessing the oxidative stress marker malondialdehyde (MDA) in oral squamous cell carcinoma (OSCC). Methodology: Pubmed (MeSH), Science Direct, Scopus, Web of Science, Willey Online Library, Cochrane, and Cross Reference were searched for studies assessing MDA levels in OSCC samples. Results: From the 1008 articles identified, 849 were excluded based on title and abstract screening due to duplication and irrelevance to the topic of interest. Full-text assessment of the remaining 159 articles led to the inclusion of only 46 articles that satisfied the selection criteria. Of these, only 26 studies had data compatible for quantitative analysis. The MDA levels in OSCC groups are significantly increased (p < 0.00001) in plasma, serum, and saliva samples in the majority of the studies evaluated. In contrast, MDA levels in OSCC tissue samples are significantly attenuated (p < 0.00001) compared to healthy controls, supported by fewer studies. Conclusions: The augmented MDA levels in plasma, serum, and saliva samples of the OSCC reflect the heightened oxidative stress level accurately. Further studies are required to understand the attenuated MDA levels in the tissue samples of OSCC. Correlation analysis between MDA levels with established clinicopathological prognostic markers could aid in formulating oxidative stress-based prognostication and treatment planning.  相似文献   
104.
Sets of tetrasubstituted thiophene esters 4a-4g, 5a-5f and 6a-6e were synthesized by reaction of 1-(alpha-Carbomethoxy-beta-aminothiocrotonoyl)-aryl/aroyl amines (3) with 3-(bromoacetyl)coumarin, 1,4-dibromodiacetyl and chloroacetone respectively. The compound 3 were synthesized by nucleophilic addition of aryl/aroylisothiocyanate and enamine (2). The synthesized targeted compounds (4a-4g, 5a-5f and 6a-6e) were evaluated for their in vivo anti-inflammatory activity in carrageenin-induced rat hind paw oedema model at three graded doses employed at 10, 20 and 40 mg/kg body weight using mefanamic acid, ibuprofen and in vivo analgesic activity in acetic acid induced writhing response model at 10 mg/kg dose using ibuprofen as standard drug. The compounds 4a-4f, 5c, 5f, 6c and 6e were evaluated for their in vitro antioxidant nitric oxide radical scavenging assay at the concentrations of 5, 10, 15, 20, 25, 30 and 35 microg/mL using ascorbic acid as standard drug. Among all the targeted compounds 4c showed maximum anti-inflammatory activity of 71% protection at 10 mg/kg and 77% protection at 20 mg/kg to inflamed paw and analgesic activity of 56% inhibition and also maximum in vitro nitric oxide radical scavenging activity having IC(50) value 31.59 microg/mL.  相似文献   
105.
An accurate comparison of the interaction of furan, pyrrole, and thiophene with different gaseous analytes is vital not only for understanding the sensing mechanism of corresponding polymers but also for rational design of new materials. In the present study, DFT calculations at (M05-2X/Aug-cc-PVDZ) have been performed to investigate the interaction behavior of furan, pyrrole, and thiophene (as models for their corresponding polymers) with different analytes (NH3, CO2, CO, N2H4, HCN, H2O2, H2S, CH4, CH3OH, SO2, SO3, H2O). The interaction of heterocycles with analytes is illustrated by changes in geometric, energetic, and electronic properties. SAPT calculations were performed for energy decomposition analysis to study the contribution of non-covalent components of the total interaction energy for each complex. Analysis of energetic and electronic properties reveals that all heterocycles are highly sensitive to SO3. The results suggest that sensing ability of polypyrrole is higher than polyfuran and polythiophene for all analytes.
Graphical abstract SAPT0 energies (kcal mol-1) of furan, pyrrole, and thiophene with various gaseous analytes?
  相似文献   
106.
Mutations in the human cellular retinaldehyde binding protein (CRALBP) gene cause retinal pathology. To understand the molecular basis of impaired CRALBP function, we have characterized human recombinant CRALBP containing the disease causing mutations R233W or M225K. Protein structures were verified by amino acid analysis and mass spectrometry, retinoid binding properties were evaluated by UV-visible and fluorescence spectroscopy and substrate carrier functions were assayed for recombinant 11-cis-retinol dehydrogenase (rRDH5). The M225K mutant was less soluble than the R233W mutant and lacked retinoid binding capability and substrate carrier function. In contrast, the R233W mutant exhibited solubility comparable to wild type rCRALBP and bound stoichiometric amounts of 11-cis- and 9-cis-retinal with at least 2-fold higher affinity than wild type rCRALBP. Holo-R233W significantly decreased the apparent affinity of rRDH5 for 11-cis-retinoid relative to wild type rCRALBP. Analyses by heteronuclear single quantum correlation NMR demonstrated that the R233W protein exhibits a different conformation than wild type rCRALBP, including a different retinoid-binding pocket conformation. The R233W mutant also undergoes less extensive structural changes upon photoisomerization of bound ligand, suggesting a more constrained structure than that of the wild type protein. Overall, the results show that the M225K mutation abolishes and the R233W mutation tightens retinoid binding and both impair CRALBP function in the visual cycle as an 11-cis-retinol acceptor and as a substrate carrier.  相似文献   
107.
Psychological sequelae of failed scalp replantation   总被引:2,自引:0,他引:2  
Published reports of avulsed scalp replant attempts have been promising. Numerous case reports and published series have demonstrated a greater than 90 percent replantation success rate. However, there exists a paucity of articles on the management of patients following failed scalp replantation attempts. The authors recognize numerous stressors that affect these patients, including the inciting traumatic event, hospitalizations, multiple surgical interventions, postsurgical therapies, and disfigurement caused by non-hair-bearing scalp. Thus, as part of the medical management for scalp replant patients, one must address the psychological factors surrounding the medical management. Over the past 25 years, the authors have experienced four cases of scalp replant failures, each posing an opportunity to examine the postoperative course of these patients. Symptoms ranging from mild anxiety to depressive symptoms have been observed in all of these patients. In fact, patient symptoms often satisfied the criteria for major depressive disorder or posttraumatic stress disorder. The authors recognize the importance of informing patients and their families of the immediate and potential long-term complications following an unsuccessful scalp replant attempt. The authors advise that all patients be provided immediate psychiatric evaluation and, if necessary, counseling and medication therapy, regardless of scalp replantation outcome.  相似文献   
108.
Two sets of iso-1-cytochrome c variants have been prepared with N-terminal insertions of pure polyglutamine, i.e., PolyQ variants, or polyglutamine interrupted with lysine every sixth residue, i.e., Gln-rich variants. The polymer properties of these pure polyGln or Gln-rich sequences have been evaluated using equilibrium and kinetic His-heme loop formation methods for loop sizes ranging from 22 to 46 in 1.5, 3.0, and 6.0 M guanidine hydrochloride (GdnHCl). In 6.0 M GdnHCl, the scaling exponent, ν3, for the pure polyGln sequences, is ∼1.7—significantly less than ν3 ≈ 2.15 for the Gln-rich sequences. The stability of the His-heme loops becomes progressively greater for the pure polyGln sequences relative to the Gln-rich sequences as GdnHCl concentration decreases from 6.0 to 1.5 M. Thus, the context of the sequence effects the polymer properties of Gln repeats even in denaturing concentrations of GdnHCl. Comparison of data for the Gln-rich variants with previous results for Gly-rich and Ala-rich variants shows that ν3 ∼ 2.2 for the Gln-rich, Gly-rich, and Ala-rich sequences in 6.0 M GdnHCl, whereas ν3 remains unchanged at 3.0 M GdnHCl concentration for the Gln-rich and Ala-rich sequences but decreases to ∼1.7 for the Gly-rich sequences. Thus, the polymer properties of Gln-rich and Ala-rich sequences are less sensitive to solvent quality in denaturing solutions of GdnHCl than Gly-rich sequences. Evaluation of Flory’s characteristic ratio, Cn, for the Gln-rich and Ala-rich sequences relative to the Gly-rich sequences shows that Gln-rich sequences are stiffer than Ala-rich sequences at both 3.0 and 6.0 M GdnHCl.  相似文献   
109.

Background

The increased heterogeneity in the distribution of social and biological risk factors makes the epidemiology of anaemia a real challenge. A cross-sectional study was conducted at Kassala, Eastern Sudan during the period of January ?? March 2011 to investigate the prevalence and predictors of anaemia among adults (> 15 years old).

Findings

Out of 646, 234 (36.2%) adults had anaemia; 68 (10.5%); 129 (20.0%) and 37 (5.7%) had mild, moderate and severe anaemia, respectively. In logistic regression analyses, age (OR?=?1.0, CI?=?0.9?C1, P?=?0.7), rural vs. urban residency (OR?=?0.9, CI?=?0.7?C1.3, P?=?0.9), female vs. male gender (OR?=?0.8, CI?=?0.6?C1.1, P?=?0.3), educational level????secondary level vs. < secondary level (OR?=?1.0, CI?=?0.6?C1.6, P?=?0.8) and Hudandawa vs. non-Hudandawa ethnicity (OR?=?0.8, CI?=?0.6?C1, P?=?0.1) were not associated with anaemia.

Conclusion

There was a high prevalence of anaemia in this setting, anaemia affected adults regardless to their age, sex and educational level. Therefore, anaemia is needed to be screened for routinely and supplements have to be employed in this setting.  相似文献   
110.
Bovine enteroviruses belong to the family Picornaviridae. Little is known about their pathogenic potential; however, they cause asymptomatic infections in cattle and are excreted in feces. In the present study, viruses isolated from environmental samples were sequenced. According to phylogenetic analyses and standard picornavirus nomenclature, these isolates constitute a new type of bovine enterovirus serogroup A.  相似文献   
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