480 research outputs found
Development of novel proteomic strategies to dissect plant phosphoproteomic signaling under environmental stresses
Protein phosphorylation is one of the important signaling mechanisms in plants which transduces environmental stimuli such as salinity, microbes, and hormones into intracellular signals and activates plant defense mechanisms. Thus, understanding the correlation between environmental stresses and alteration of plant phosphorylation requires system-wide phosphoproteomic analysis, which includes identification of kinase-substrate complexes and measurement of phosphorylation-mediated signaling changes. However, identification and quantification of plant phosphoproteome remains challenging due to the highly dynamic nature of plant proteome, interferences of cell wall, pigments, and secondary metabolites. Recently, mass spectrometry (MS) has been integrated with phosphopeptide enrichment approaches for identifying thousands of phosphorylation sites and for quantifying phosphoprotein stoichiometry. Although MS-based phosphoproteomics has revealed the global phosphorylation changes related to different physiological states of plants, many kinase-substrate networks involved in essential signaling pathways, such as the ABA-induced SNF-1-related protein kinase 2 (SnRK2) pathway and the mitogen-activated protein kinases (MAPKs) cascades, are still not completely understood. This dissertation discusses strategies for improving plant sample preparation and for identifying the direct substrates of the plant kinases. Chapter one highlights the low phosphopeptide identification rate by mass spectrometry. Chapter two details the development of a sample preparation protocol for the plant phosphoproteome analysis, and the application of the protocol for the study of tomato cold-induced phosphoproteomic changes. Chapter three shows the development of a novel approach for identification of the direct substrates of the plant kinases, whose activation regulates the signaling transductions of plant stress defense mechanisms
Ensuring Teaching Continuity: Chilean University Studentsâ Perception on Remote Teaching of English during COVID 19 Pandemic
The objective of our study is to know the perception of Chilean university students toward the pedagogical methodologies in online English classes during the COVID-19 pandemic. We applied a questionnaire (built by fifteen experts, validated through a pilot test of 34 students, and improved with licensed 21.0 version SPSS in terms of consistency) to 341 students from different university programs. We analyzed the responses quantitatively and qualitatively and found out that 75% of the 341 students surveyed have shown agreement with the pedagogical methodologies applied in online classes and motivation in learning due to the permanent concern and communication of the teacher in charge. Besides, the students have also yielded satisfactory learning outcomes. These results reveal that the online English teaching of Chilean higher education during the pandemic has been good and indirectly show the willingness of Chilean university teachers to receive relevant and continuous training to deliver quality education. In 2022, many countries have returned to face-to-face classes, but we believe that the pedagogical methodologies used in this research could serve as a reference for teachers or researchers worldwide who wish to incorporate into their face-to-face classes a part of online teaching and do research on online English teaching
Honokiol Protected against Heatstroke-Induced Oxidative Stress and Inflammation in Diabetic Rats
We aimed at investigating the effect of honokiol on heatstroke in an experimental rat model. Sprogue-Dawley rats were divided into 3 groups: normothermic diabetic rats treated with vehicle solution (NTDR+V), heatstroke-diabetic rats treated with vehicle (HSDR+V), and heatstroke rats treated with konokiol (0.5â5âmg/ml/kg) (HSDR+H). Sixty minutes before the start of heat stress, honokiol or vehicle solution was administered. (HSDR+H) significantly (a) attenuated hyperthermia, hypotension and hypothalamic ischemia, hypoxia, and neuronal apoptosis; (b) reduced the plasma index of the toxic oxidizing radicals; (c) diminished the indices of hepatic and renal dysfunction; (d) attenuated the plasma systemic inflammatory response molecules; (e) promoted plasma levels of an anti-inflammatory cytokine; (f) reduced the index of infiltration of polymorphonuclear neutrophils in the serum; and (g) promoted the survival time fourfold compared with the (HSDR+V) group. In conclusion, honokiol protected against the outcome of heatstroke by reducing inflammation and oxidative stress-mediated multiple organ dysfunction in diabetic rats
Protective effect of transgenic expression of porcine heat shock protein 70 on hypothalamic ischemic and oxidative damage in a mouse model of heatstroke
<p>Abstract</p> <p>Background</p> <p>Transgenic mice have been used to examine the role of heat shock protein (HSP)72 in experimental heatstroke. Transgenic mice that were heterozygous for a porcine HSP70β gene ([+] HSP72) and transgene-negative littermate controls ([-] HSP72), under pentobarbital sodium anesthesia, were subjected to heat stress to induce heatstroke. It was found that the overexpression of HSP72 in multiple organs improved survival during heatstroke by reducing hypotension and cerebral ischemia and damage in mice. Herein we attempted to further assess the effect of heat exposure on thermoregulatory function, hypothalamic integration, and survival in unrestrained, unanesthetized [+]HSP72 and compare with those of [-]HSP72. In this research with the transgenic mice, we first conducted several biochemical, physiologic and histological determinations and then investigated the beneficial effects of HSP72 overexpression on the identified hypothalamic deficits, thermoregulatory dysfunction, and mortality during heatstroke.</p> <p>Results</p> <p>We report here that when [-]HSP72 mice underwent heat stress (ambient temperature 42.4°C for 1 h), the fraction survival and core temperature at 4 h after heat stress were found to be 0 of 12 and 34.2°C ¹ 0.4°C, respectively. Mice that survived to day 4 after heat stress were considered as survivors. In [+]HSP72 mice, when exposed to the same heat treatment, both fraction survival and core temperature values were significantly increased to new values of 12/12 and 37.4°C ¹ 0.3°C, respectively. Compared to [-]HSP mice, [+]HSP72 mice displayed lower hypothalamic values of cellular ischemia (e.g., glutamate and lactate-to-pyruvate ratio) and damage (e.g., glycerol) markers, pro-oxidant enzymes (e.g., lipid peroxidation and glutathione oxidation), pro-inflammatory cytokines (e.g., interleukin-1beta and tumor necrosis factor-alpha), and neuronal damage score evaluated 4 h after heat stress. In contrast, [+]HSP72 mice had higher hypothalamic values of antioxidant defences (e.g., glutathione peroxidase and glutathione reductase), ATP, and HSP72 expression.</p> <p>Conclusion</p> <p>This study indicates that HSP72 overexpression appears to be critical to the development of thermotolerance and protection from heat-induced hypothalamic ischemic and oxidative damage.</p
Hepatoid adenocarcinoma of the stomach with liver metastasis mimicking hepatocellular carcinoma: a case report
The Design and Implementation of Scrambling Wavelength Hopping with AWG Router and Optical Switch over Secure WDM Network
In current experimental design, by exchanging the optical switch configured in front of arrayed waveguide grating (AWG) router, the wavelength hopping configuration was implemented over wavelength division multiplexing (WDM) network. In addition, in order to enhance the variable wavelength hopping pattern of proposed scheme, the transceiver oscillators were used to trigger the optical switch by a series of random and un-predictable electrical signal. The experiment results proved possible solution of secure WDM network that the wavelength hopping effect was monitored by optical spectrum analyzer (OSA) in optical domain. By using the oscilloscope for monitoring, the results showed the transmitted analogy signal of 10MHzwas extracted correctly by photo-detector while the wavelength hopping is happene
Risk of Vertebral Fracture in Patients Diagnosed with a Depressive Disorder: A Nationwide Population-Based Cohort Study
OBJECTIVE: Previous studies have reported that depression may play a crucial role in the occurrence of vertebral fractures. However, a clear correlation between depressive disorders and osteoporotic fractures has not been established. We explored the association between depressive disorders and subsequent new-onset vertebral fractures. Additionally, we aimed to identify the potential risk factors for vertebral fracture in patients with a depressive disorder. METHODS: We studied patients listed in the Taiwan National Health Insurance Research Database who were diagnosed with a depressive disorder by a psychiatrist. The comparison cohort consisted of age- and sex-matched patients without a depressive disorder. The incidence rate and hazard ratios of subsequent vertebral fracture were evaluated. We used Cox regression analysis to evaluate the risk of vertebral fracture among patients with a depressive disorder. RESULTS: The total number of patients with and without a depressive disorder was 44,812. The incidence risk ratio (IRR) between these 2 cohorts indicated that depressive disorder patients had a higher risk of developing a subsequent vertebral fracture (IRR=1.41, 95% confidence interval [CI]=1.26-1.57,
A panel of tumor markers, calreticulin, annexin A2, and annexin A3 in upper tract urothelial carcinoma identified by proteomic and immunological analysis
BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a tumor with sizable metastases and local recurrence. It has a worse prognosis than bladder cancer. This study was designed to investigate the urinary potential tumor markers of UTUC. METHODS: Between January 2008 and January 2009, urine was sampled from 13 patients with UTUC and 20 healthy adults. The current study identified biomarkers for UTUC using non-fixed volume stepwise weak anion exchange chromatography for fractionation of urine protein prior to two-dimensional gel electrophoresis. RESULTS: Fifty five differential proteins have been determined by comparing with the 2-DE maps of the urine of UTUC patients and those of healthy people. Western blotting analysis and immunohistochemistry of tumor tissues and normal tissues from patients with UTUC were carried out to further verify five possible UTUC biomarkers, including zinc-alpha-2-glycoprotein, calreticulin, annexin A2, annexin A3 and haptoglobin. The data of western blot and immunohistochemical analysis are consistent with the 2-DE data. Combined the experimental data in the urine and in tumor tissues collected from patients with UTUC, the crucial over-expressed proteins are calreticulin, annexin A2, and annexin A3. CONCLUSIONS: Calreticulin, annexin A2, and annexin A3 are very likely a panel of biomarkers with potential value for UTUC diagnosis
Albuminâ bilirubin gradeâ based nomogram of the BCLC system for personalized prognostic prediction in hepatocellular carcinoma
Background & AimsThe prognostic accuracy of individual hepatocellular carcinoma (HCC) patient in each Barcelona Clinic Liver Cancer (BCLC) stage is unclear. We aimed to develop and validate an albuminâ bilirubin (ALBI) gradeâ based nomogram of BCLC to estimate survival for individual HCC patient.MethodsBetween 2002 and 2016, 3690 patients with newly diagnosed HCC were prospectively enrolled and retrospectively analysed. Patients were randomly split into derivation and validation cohort by 1:1 ratio. Multivariate Cox proportional hazards model was used to generate the nomogram from tumour burden, ALBI grade and performance status (PS). The concordance index and calibration plot were determined to evaluate the performance of this nomogram.ResultsBeta coefficients from the Cox model were used to assign nomogram points to different degrees of tumour burden, ALBI grade and PS. The scores of the nomogram ranged from 0 to 24, and were used to predict 3â and 5â year patient survival. The concordance index of this nomogram was 0.77 (95% confidence interval [CI]: 0.71â 0.81) in the derivation cohort and 0.76 (95% CI: 0.71â 0.81) in the validation cohort. The calibration plots to predict both 3â and 5â year survival rate well matched with the 45â degree ideal line for both cohorts, except for ALBIâ based BCLC stage 0 in the validation cohort.ConclusionsThe proposed ALBIâ based nomogram of BCLC system is a simple and feasible strategy in the precision medicine era. Our data indicate it is a straightforward and userâ friendly prognostic tool to estimate the survival of individual HCC patient except for very early stage patients.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153250/1/liv14249_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153250/2/liv14249.pd
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