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41.
Ready-to-eat (RTE) meats (low-fat pastrami, Strassburg beef, export sausage, and Cajun beef) were pressure treated at 600 MPa, 20 degrees C, for 180 s to evaluate the feasibility of using high-pressure processing (HPP) for the safe shelf-life extension of these products. After processing, samples were stored at 4 degrees C for 98 days during which time microbiological enumeration and enrichments were performed. Additionally, sensory analyses were undertaken to determine consumer acceptability and purchase intent over the duration of storage. Counts of aerobic and anaerobic mesophiles, lactic acid bacteria, Listeria spp., staphylococci, Brochothrix thermosphacta, coliforms, and yeasts and molds revealed that there were undetectable or low levels for all types of microorganisms throughout storage. Comparison of consumer hedonic ratings for unprocessed and processed meats revealed no difference in consumer acceptability, and no deterioration in the sensory quality was evident for any of the products tested during the study. Additionally, inoculated pack studies were conducted to determine if HPP could be used as a postlethality treatment to reduce or eliminate Listeria monocytogenes and thus assess the potential use of HPP in a hazard analysis critical control point plan for production of RTE meats. Inoculated samples (initial level of 10(4) CFU/g) were pressure treated (600 MPa, 20 degrees C, for 180 s) and stored at 4 degrees C, and survival of L. monocytogenes was monitored for 91 days. L. monocytogenes was not detected by plating methods until day 91, but selective enrichments showed sporadic recovery in three of the four products examined. The results show that HPP at 600 MPa, 20 degrees C, for 180 s can extend the refrigerated shelf life of RTE meats and reduce L. monocytogenes numbers by more than 4 log CFU/g in inoculated product.  相似文献   
42.
RADA16 self-assembling peptide nanofiber scaffolds (SAPNSs) have been shown to have positive effects on neural regeneration following injury to the central nervous system in vivo, but mechanisms are unclear. Here we show that RADA16 SAPNSs form scaffolds of increasing fiber density with increasing peptide concentration which in turn has a concentration-dependent effect on neurons and astrocytes in mixed retinal cultures. Importantly, we report that the final nanoscale fiber architecture is an important factor to consider in designing scaffolds to promote regeneration in the central nervous system.  相似文献   
43.
Early detection, characterization and monitoring of cancer are possible by using extracellular vesicles (EVs) isolated from non-invasively obtained liquid biopsy samples. They play a role in intercellular communication contributing to cell growth, differentiation and survival, thereby affecting the formation of tumor microenvironments and causing metastases. EVs were discovered more than seventy years ago. They have been tested recently as tools of drug delivery to treat cancer. Here we give a brief review on extracellular vesicles, exosomes, microvesicles and apoptotic bodies. Exosomes play an important role by carrying extracellular nucleic acids (DNA, RNA) in cell-to-cell communication causing tumor and metastasis development. We discuss the role of extracellular vesicles in the pathogenesis of cancer and their practical application in the early diagnosis, follow up, and next-generation treatment of cancer patients.  相似文献   
44.
Glioblastoma is one of the most common and lethal types of primary brain tumor. Despite aggressive treatment with chemotherapy and radiotherapy, tumor recurrence within 6–9 months is common. To overcome this, more effective therapies targeting cancer cell stemness, invasion, metabolism, cell death resistance and the interactions of tumor cells with their surrounding microenvironment are required. In this study, we performed a systematic review of the molecular mechanisms that drive glioblastoma progression, which led to the identification of 65 drugs/inhibitors that we screened for their efficacy to kill patient-derived glioma stem cells in two dimensional (2D) cultures and patient-derived three dimensional (3D) glioblastoma explant organoids (GBOs). From the screening, we found a group of drugs that presented different selectivity on different patient-derived in vitro models. Moreover, we found that Costunolide, a TERT inhibitor, was effective in reducing the cell viability in vitro of both primary tumor models as well as tumor models pre-treated with chemotherapy and radiotherapy. These results present a novel workflow for screening a relatively large groups of drugs, whose results could lead to the identification of more personalized and effective treatment for recurrent glioblastoma.  相似文献   
45.
Inappropriate nutrition and a sedentary lifestyle can lead to obesity, one of the most common risk factors for several chronic diseases. Although regular physical exercise is an efficient approach to improve cardiometabolic health, the exact cellular processes are still not fully understood. We aimed to analyze the morphological, gene expression, and lipidomic patterns in the liver and adipose tissues in response to regular exercise. Healthy (wild type on a normal diet) and hyperlipidemic, high-fat diet-fed (HFD-fed) apolipoprotein B-100 (APOB-100)-overexpressing mice were trained by treadmill running for 7 months. The serum concentrations of triglyceride and tumor necrosis factor α (TNFα), as well as the level of lipid accumulation in the liver, were significantly higher in HFD-fed APOB-100 males compared to females. However, regular exercise almost completely abolished lipid accumulation in the liver of hyperlipidemic animals. The expression level of the thermogenesis marker, uncoupling protein-1 (Ucp1), was significantly higher in the subcutaneous white adipose tissue of healthy females, as well as in the brown adipose tissue of HFD-fed APOB-100 females, compared to males. Lipidomic analyses revealed that hyperlipidemia essentially remodeled the lipidome of brown adipose tissue, affecting both the membrane and storage lipid fractions, which was partially restored by exercise in both sexes. Our results revealed more severe metabolic disturbances in HFD-fed APOB-100 males compared to females. However, exercise efficiently reduced the body weight, serum triglyceride levels, expression of pro-inflammatory factors, and hepatic lipid accumulation in our model.  相似文献   
46.
In a cross-validated mediational model, the authors examined characteristics of memories formed in response to rape and other intense unpleasant and pleasant experiences. Data were responses to a mailed survey of women medical center and university employees. Measurement models of memory and symptom factors and a structural model with pathways among cognitive appraisal, emotional valence, memory characteristics, and health outcomes were developed in Sample I (N?=?1,307) and confirmed in Sample 2 (N?=?2,142). Rape had substantial direct effects on 2 memory factors (Clarity and Affect) and indirect effects through the construal of victimization. Rape was associated with memories described as more emotionally intense but less clear and coherent and less often thought of or talked about. Most effects on physical symptoms were nonsignificant. Implications of findings for neurohormonal and multiple representation models of emotional memory and to cognitive avoidance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
47.
The development, reliability, and discriminative ability of a new instrument to assess social phobia are presented. The Social Phobia and Anxiety Inventory (SPAI) is an empirically derived instrument incorporating responses from the cognitive, somatic, and behavioral dimensions of social fear. The SPAI high test–retest reliability and good internal consistency. The instrument appears to be sensitive to the entire continuum of socially anxious concerns and is capable of differentiating social phobics from normal controls as well as from other anxiety patients. The utility of this instrument for improved assessment of social phobia and anxiety and its use as an aid for treatment planning are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
Personality judgments of 184 targets were provided by the self, college acquaintances, hometown acquaintances, parents, and strangers. Study 1 found that knowing the target in the same context enhanced but was not necessary for interjudge agreement and that acquaintances who had never met agreed with each other as well as those who had met. Study 2 found that personality judgments by acquaintances manifested much better interjudge and self–other agreement than did judgments by strangers. Acquaintances were not more similar to their targets than were strangers, and their accuracy derived more from their distinctive judgment of the target than from assumed similarity. These results rule out overlap, communication, and assumed similarity as necessary bases of interjudge agreement and thereby support the simpler hypothesis that interjudge agreement stems from mutual accuracy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
Examined whether differences between poor and normal reading children on lexical memory tasks may be attributed to semantic development, using 80 2nd and 6th graders. Ss were presented with 4 lists of taxonomic categories and were asked to recall items under (a) noncued and random conditions, with Ss instructed to recall as many items as possible and (b) cued and blocked conditions, with Ss told to recall items in a category. All Ss performed better with category cues. Group differences on category recall were more reliable at Grade 6, suggesting that facility in accessing taxonomic categories may differentiate poor and normal readers more reliably at older age levels. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
Parental behavior and pup development in meadow and prairie voles were examined. Social units were manipulated for the presence of fathers and of juveniles. Meadow vole mothers alone with pups showed less maternal care and spent more time resting than did mothers with juveniles or with fathers and juveniles. Pups reared only with mothers developed faster than did pups under other conditions. Number of animals in the social unit was negatively correlated with the rate of pup development. Meadow vole fathers and juveniles showed no parental care. In contrast, prairie vole mothers spent less time in the nest when both fathers and juveniles were present. Fathers assisted in rearing pups, and litters developed more rapidly when fathers were present. Juveniles remained in the natal nest and engaged in parentlike behavior. The findings relate to differences in the life history strategy for the 2 vole species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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