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91.
Liver cancer is one of the most frequent solid cancers. The major risk factor associated with the development of hepatocellular carcinoma (HCC) is cirrhosis caused by hepatitis B, hepatitis C virus or chronic alcohol consumption. The overall prognosis of patients with HCC is very poor and this is mainly due to the advanced stages of cancer at presentation and also because of underlying cirrhosis. When HCC is diagnosed at early stages, prognosis is better with five-year disease free survival of around 50% with resection, or local ablative treatments such as radio-frequency ablation or percutaneous ethanol injection, and 70-80% with liver transplantation. Therefore, systematic screening of all the high-risk patients is the key to an early diagnosis of small HCC and the use of an appropriate treatment modality. The currently available tools for the screening, surveillance and diagnosis of HCC in the presence of cirrhosis remain sub-optimal. The advancements made in the past 10 years, however, have made HCC a potentially curable disease in a highly selected group of patients. This review will briefly discuss the current guidelines for surveillance and diagnosis of HCC in high-risk subjects and then review the potential role of endoscopic ultrasound and fine needle aspiration for the diagnosis of small HCC.  相似文献   
92.
The present investigation assessed the applicability of incense stick ash, a novel and sustainable adsorbent for remediation of Victoria Blue dye from wastewater. Incense stick ash, without any physical and chemical treatment has been applied to investigate the influence of various experimental parameters as pH, loading of adsorbent, concentration, shaking time, temperature and ionic strength on Victoria Blue remediation in a batch operation. Incense stick ash was characterized using BET, DLS, SEM-EDS, FTIR and XRD techniques. BET surface area, pore volume and pore diameter of incense stick ash are obtained as 2.245 m2 g?1, 0.0118 cm3 g?1 and 21.02 nm, respectively. Average particle size of the adsorbent is obtained as 293.2 nm. Goodness of the fit of isotherm and kinetic model to the reported data was identified based on chi squared and coefficient of determination values. Isotherm and kinetic behavior was best represented by Freundlich and pseudo 2nd order equation, respectively. Boyd model confirmed involvement of film diffusion mechanism along with intra-particle for adsorption of Victoria Blue on incense stick ash. Maximum dye uptake was reported as 105.57 mg g?1. Thermodynamic study revealed spontaneous and favorable adsorption of Victoria Blue on incense stick ash at higher temperature. The performed elution and subsequent regeneration study implied desorption capability of incense stick ash and its applicability as a fresh adsorbent for further cycle of adsorption. The overall study implied scavenging potential of incense stick ash, a novel and sustainable adsorbent available at zero cost towards Victoria Blue removal.  相似文献   
93.
Alzheimer’s disease (AD) is associated with deficits in a number of cognitive processes and executive functions. Moreover, abnormalities in the electroencephalogram (EEG) power spectrum develop with the progression of AD. These features have been traditionally characterized with montage recordings and conventional spectral analysis during resting eyes-closed and resting eyes-open (EO) conditions. In this study, we introduce a single lead dry electrode EEG device which was employed on AD and control subjects during resting and activated battery of cognitive and sensory tasks such as Paced Auditory Serial Addition Test (PASAT) and auditory stimulations. EEG signals were recorded over the left prefrontal cortex (Fp1) from each subject. EEG signals were decomposed into sub-bands approximately corresponding to the major brain frequency bands using several different discrete wavelet transforms and developed statistical features for each band. Decision tree algorithms along with univariate and multivariate statistical analysis were used to identify the most predictive features across resting and active states, separately and collectively. During resting state recordings, we found that the AD patients exhibited elevated D4 (~4–8 Hz) mean power in EO state as their most distinctive feature. During the active states, however, the majority of AD patients exhibited larger minimum D3 (~8–12 Hz) values during auditory stimulation (18 Hz) combined with increased kurtosis of D5 (~2–4 Hz) during PASAT with 2 s interval. When analyzed using EEG recording data across all tasks, the most predictive AD patient features were a combination of the first two feature sets. However, the dominant discriminating feature for the majority of AD patients were still the same features as the active state analysis. The results from this small sample size pilot study indicate that although EEG recordings during resting conditions are able to differentiate AD from control subjects, EEG activity recorded during active engagement in cognitive and auditory tasks provide important distinct features, some of which may be among the most predictive discriminating features.  相似文献   
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The alarm response is an antipredator behavior displayed by many fish species and was first described 70 years ago. It is triggered through the olfactory system by substances released from injured skin and is characterized by dramatic, measurable changes in locomotion as well as physiology. We propose that this is an ideal time to revisit this response and to utilize it as an assay for understanding how neural circuits mediate innate fear. A suitable organism for these studies is the zebrafish, a genetic model with a rapidly expanding toolkit for molecular manipulation of the nervous system. Individual neurons mediating the response, ranging from receptor neurons to those in higher brain centers, should first be identified. New tools, specifically transgenic lines that allow spatial and temporal control of neural activity, provide a way to define and test the role of specific neurons, while genetic screens provide a route to identifying individual molecules essential for a normal response. Optical recording, which has proven successful in studies of information processing in the bulb, will provide valuable insights into neural circuitry function during the alarm response. When carried out on mutants, physiological analysis can provide insight into aspects of signal processing that are essential for normal behavior. The alarm response thus provides a paradigm to examine innate fear in a vertebrate system, enabling analysis at multiple levels from genes to the entire neural circuit. Additionally, the context dependency of the response can be utilized to investigate attention and decision making.  相似文献   
96.
Protein aggregation and ordered fibrillar amyloid deposition inside and outside of the central nervous system cells is the common pathologic hallmark of most aging-related neurodegenerative disorders. Dominant mutations in the gene encoding superoxide dismutase 1 (SOD1) protein are linked to familial amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive degeneration of motor neurons, leading to muscle paralysis and death. The major histochemical hallmark in the remaining motor neurons of ALS is the intracellular accumulation of ubiquitinated inclusions consisting of insoluble aberrant protein aggregates. However, the molecular pathomechanisms underlying the process have been elusive. Here for the first time, we report that E6-AP, a homologous to E6-AP C terminus-type E3 ubiquitin ligase depleted in ALS mouse models before neurodegeneration. E6-AP coimmunoprecipitates with the SOD1 protein and is predominantly mislocalized in mutant SOD1-containing inclusion bodies. Overexpression of E6-AP increases the ubiquitination and facilitates degradation of SOD1 proteins. Finally, we show that the overexpression of E6-AP suppresses the aggregation and cell death mediated by mutated SOD1 proteins and cellular protective effect is more prominent when E6-AP is overexpressed along with Hsp70. These data suggest that enhancing the activity of E6-AP ubiquitin ligase might be a viable therapeutic strategy to eliminate mutant SOD1-mediated toxicity in ALS.  相似文献   
97.
Tendinopathies are common muskoloskeletal injuries that lead to pain and disability. Development and pathogenesis of tendinopathy is attributed to progressive pathological changes to the structure, function, and biology of tendon. The nature of this disease state, whether acquired by acute or chronic injury, is being actively investigated. Scarring, disorganized tissue, and loss of function characterize adult tendon healing. Recent work from animal models has begun to reveal the potential for adult mammalian tendon regeneration, the replacement of diseased with innate tissue. This review discusses what is known about musculoskeletal regeneration from a molecular perspective and how these findings can be applied to tendinopathy. Non‐mammalian and mammalian models are discussed with emphasis on the potential of Murphy Roths Large mice to serve as a model of adult tendon regeneration. Comparison of regeneration in non‐mammals, foetal mammals and adult mammals emphasizes distinctly different contributing factors to effective regeneration.  相似文献   
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This work presents smart pathways to enhance the photocatalytic activity of TiO2via co-doping with fluorine (F) and platinum (Pt) to form F–Pt co-doped TiO2 photocatalysts and investigates the unique and unusual fluorination of the floated products. Our investigations indicate that the crystalline structure of the photocatalysts was a mixture of anatase and brookite phases and that the nanoparticles of the synthesized nanocomposites had nanometric sizes (4–25 nm). The F–Pt co-doped TiO2 nano-photocatalysts demonstrated degradation of sulfamethoxazole (SMX) drug of >93% within 90 min under direct solar light and 58% degradation within 360 min under a solar simulator. Thus, co-doping TiO2 with F and Pt atoms to form F–Pt co-doped TiO2 nanocomposite is an efficient pathway to achieve high photocatalytic performance escorted with the formation of floating metal-fluoropolymer, unlike pristine TiO2 which has less photocatalytic degradation and no generation of a floating polymer. Our photocatalytic protocol demonstrates that the degradation of SMX started with redox reactions of oxygen and water absorbed on the surface of the prepared nanocomposites to form superoxide anions (O2˙) and hydroxy radicals (˙OH) which have oxidation superpower. The resultant products were subsequently fluorinated by fluoride radical ions and floated as metal-fluoropolymer.

This work presents smart pathways to enhance the photocatalytic activity of TiO2via co-doping with fluorine (F) and platinum (Pt) to form F–Pt co-doped TiO2 photocatalysts and investigates the unique and unusual fluorination of the floated products.  相似文献   
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