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1.
Neural Regen Res ; 17(6): 1210-1227, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34782555

RESUMO

Age-related neurodegenerative disorders such as Alzheimer's disease (AD) have become a critical public health issue due to the significantly extended human lifespan, leading to considerable economic and social burdens. Traditional therapies for AD such as medicine and surgery remain ineffective, impractical, and expensive. Many studies have shown that a variety of bioactive substances released by physical exercise (called "exerkines") help to maintain and improve the normal functions of the brain in terms of cognition, emotion, and psychomotor coordination. Increasing evidence suggests that exerkines may exert beneficial effects in AD as well. This review summarizes the neuroprotective effects of exerkines in AD, focusing on the underlying molecular mechanism and the dynamic expression of exerkines after physical exercise. The findings described in this review will help direct research into novel targets for the treatment of AD and develop customized exercise therapy for individuals of different ages, genders, and health conditions.

2.
J Phys Chem Lett ; : 11578-11584, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34807621

RESUMO

Scaling relations play a vital role in high-throughput screening of catalytic materials, and more and more attention is being paid to strain-based regulation of catalytic performance. Here we investigated the variation of several energetics, including adsorption energies in the initial state, transition state, and final state, reaction energies, and energy barriers with strain, by studying CO, BH, NH, CH, and NO adsorption and dissociation on M(111) (M = Cu, Ag, Ni, Pd, or Pt) surfaces. We show that energy barriers, reaction energies, and adsorption energies can vary either linearly or nonlinearly (quadratically) with strain. Systems with stronger adsorbate-substrate interaction and weaker atom-atom interaction in substrates are more likely to exhibit nonlinear relations. The well-known Brønsted-Evans-Polanyi relationships and transition state scaling relationships under strain were also examined, and both of them can be nonlinear under strain, in principle. The observed nonlinear relationships were satisfactorily rationalized with the equations derived from Mechanics of Solids.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34802928

RESUMO

Herein, a fluorescent nanosensor has been constructed for detection of glutathione (GSH) based on NH2-UiO-66 and AgNPs. The NH2-UiO-66 was synthesized where 2-amino-terephthalic acid as the organic ligand and Zr4+ as the center metal ions. The AgNPs can enhance the fluorescence of NH2-UiO-66 based on metal enhanced fluorescence (MEF) effect. Moreover, in the present of GSH, the fluorescence of NH2-UiO-66@AgNPs was quenched via electrostatic interaction and Ag-S reaction. The present sensing strategy shows good linear relation with the concentration of GSH in the range of 0.2-1.0 µM and 1.0-30 µM, and the limit of detection is 79 nM. Furthermore, our fluorescent nanosensor was utilized to detect GSH in human serum with a recovery of 96.8-102.5%. The results indicated that NH2-UiO-66@AgNPs is successfully applied for high sensitive and selective detection of GSH in human serum.

4.
Inflammation ; 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783942

RESUMO

Hyperglycemia-induced oxidative stress in podocytes exerts a major role in the pathological process of diabetic nephropathy. Tripartite motif-containing protein 32 (TRIM32) has been reported to be a key protein in the modulation of cellular apoptosis and oxidative stress under various pathological processes. However, whether TRIM32 participates in the regulation of high glucose (HG)-induced injury in podocytes has not been investigated. This work aimed to assess the possible role of TRIM32 in mediating HG-induced apoptosis, oxidative stress, and inflammatory response in podocytes in vitro. Our results showed a marked increase in TRIM32 expression in HG-exposed podocytes and the glomeruli of diabetic mice. Loss-of-function experiments showed that TRIM32 knockdown improves the viability of HG-stimulated podocytes and suppresses HG-induced apoptosis, oxidative stress, and inflammatory responses in podocytes. Further investigation revealed that TRIM32 inhibition enhances the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) signaling, which is associated with the modulation of the Akt/glycogen synthase kinase-3ß (GSK-3ß) axis in podocytes following HG exposure. However, Akt suppression abrogated the TRIM32 knockdown-mediated activation of Nrf2 in HG-exposed podocytes. Nrf2 knockdown also markedly abolished the protective effects induced by TRIM32 inhibition o in HG-exposed podocytes. In summary, this work demonstrated that TRIM32 inhibition protects podocytes from HG-induced injury by potentiating Nrf2 signaling through modulation of Akt/GSK-3ß signaling. The findings reveal the potential role of TRIM32 in mediating podocyte injury during the progression of diabetic nephropathy.

5.
Shock ; 56(6): 948-955, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34779798

RESUMO

BACKGROUND: Hyperfibrinolysis and pro/anti-inflammatory imbalance usually occur in the early stage of severe burns. Soluble urokinase-type plasminogen activator receptor (suPAR) is involved in fibrinolysis and inflammation. To date, the levels of circulating suPAR in non-survivors with severe burns remain unknown. This study aimed to investigate the early association between circulating suPAR levels and biomarkers of fibrinolysis, pro/anti-inflammatory, and prognosis. METHODS: Sixty-four consecutive Chinese patients with severe burns and 26 healthy volunteers were enrolled in a prospective observational cohort. Clinical characteristics and laboratory data were collected prospectively. Blood samples were collected at 48 h post-burn, and suPAR and biomarkers of pro/anti-inflammatory and fibrinolysis were detected by enzyme-linked immunosorbent assays. Important indicators between non-survivors and survivors were compared. Linear regression analysis was performed to screen variables associated with suPAR. Logistic regression analysis and receiver operating characteristic curve (ROC) analysis were performed to evaluate the prognostic value of suPAR. RESULT: Compared with the control group, the circulating suPAR levels in the survivors (P < 0.001) and non-survivors (P = 0.017) were higher. Compared with survivors, non-survivors had lower circulating suPAR levels at 48 h post-burn, and they showed a higher degree of fibrinolysis (higher D-dimer) and a lower TNF-α/IL-10 ratio. According to linear regression analysis, the variables independently associated with a lower suPAR level were lower platelet factor 4 (PF-4), urokinase-type plasminogen activator (uPA), and TNF-α/IL-10 levels and a higher D-dimer level. Logistic regression and ROC analyses indicated that a suPAR level ≤ 4.70 µg/L was independently associated with 30-day mortality. CONCLUSION: Low circulating suPAR levels at 48 h post-burn in severe burn patients may reflect decreased TNF-α/IL-10 ratio and increased hyperfibrinolysis. suPAR can predict 30-day mortality in patients with severe burn.

6.
J Phys Chem A ; 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34793164

RESUMO

To provide guiding information for developing efficient and stable catalysts for epoxide hydration, we investigated the mechanism of propylene oxide (PO) to 1,2-propylene glycol (PG) using density functional theory (DFT) calculations. The mechanism was identified to follow the cooperative bimetallic mechanism in which a metal-salen complex activated H2O attacks the middle carbon atom of a metal-salen complex activated PO from the oxygen side of three-membered ring. Analyses reveal that the distortion energy correlates linearly with the barrier, and the hydrogen bonding between H2O and PO increases from reaction precursors to transition states. A nice linear relationship exists between the ratio of square root of ionic potential to the square of the distance from the metal ion spherical surface to the oxygen atom center of PO. It is demonstrated that the substrates with larger polarizability tend to have lower hydration barriers and the influence of ligands is less than that of metal centers and substrates. Modifying metal ions is the first choice for developing metal-salen catalysts, and metal ions with more formal charges and larger radius are expected to exhibit high activity. These findings shed lights on the mechanism and provide guiding information for developing efficient metal-salen catalysts for epoxide hydration.

8.
Shock ; 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34812187

RESUMO

BACKGROUND: : Platelet distribution width (PDW) and PDW-to-platelet ratio (PPR) have been proven to be good prognostic indicators for many diseases. However, their prognostic values in severe burns have not been reported. OBJECTIVE: : To investigate the early time course of PDW and PPR in severe burn patients and investigate their prognostic values. METHODS: : This is a 16-year, single-center retrospective study of 590 severe burn patients. The complete blood count parameters on day 1, day 3 and day 7 postburn, including PDW and PPR, were collected. Receiver operating characteristic curves (ROC) analysis, multiple logistic regression analysis and Kaplan-Meier survival analysis were performed to evaluate the prognostic values of PDW and PPR in severe burn patients. RESULTS: : According to 120-day follow-up records, 96 patients were non-survivors and 494 patients were survivors. ROC and area under the curve (AUC) analysis showed that, for predicting 120-day prognosis, the AUC of PDW (0.782) and PPR (0.816) on day 3 was the highest, followed by the AUC of PDW (0.764) and PPR (0.750) on day 7. The ROC-AUC of PPR (0.816) on day 3 was very close to that of the ABSI score (0.818). Multiple logistic regression analysis showed that the PDW (P = 0.033 and P = 0.009) and PPR (P = 0.052 and P = 0.046) on day 3 and day 7 were all significantly independently positively associated with 120-day mortality. Kaplan-Meier survival analysis showed that high PDW and PPR were both significantly associated with a high 120-day mortality rate on day 3 and day 7. CONCLUSION: : PDW and PPR on day 3 and day 7 were independent risk factors for 120-day mortality in severe burn patients. These objective and readily available prognostic indicators may be more clinically favored.

9.
PLoS One ; 16(11): e0259529, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34735529

RESUMO

BACKGROUND: Early-stage oral squamous cell carcinoma (OSCC) patients have a one-in-four risk of regional metastasis (LN+), which is also the most significant prognostic factor for survival. As there are no validated biomarkers for predicting LN+ in early-stage OSCC, elective neck dissection often leads to over-treatment and under-treatment. We present a machine-learning-based model using the quantitative nuclear phenotype of cancer cells from the primary tumor to predict the risk of nodal disease. METHODS AND FINDINGS: Tumor specimens were obtained from 35 patients diagnosed with primary OSCC and received surgery with curative intent. Of the 35 patients, 29 had well (G1) or moderately (G2) differentiated tumors, and six had poorly differentiated tumors. From each, two consecutive sections were stained for hematoxylin & eosin and Feulgen-thionin staining. The slides were scanned, and images were processed to curate nuclear morphometric features for each nucleus, measuring nuclear morphology, DNA amount, and chromatin texture/organization. The nuclei (n = 384,041) from 15 G1 and 14 G2 tumors were randomly split into 80% training and 20% test set to build the predictive model by using Random Forest (RF) analysis which give each tumor cell a score, NRS. The area under ROC curve (AUC) was 99.6% and 90.7% for the training and test sets, respectively. At the cutoff score of 0.5 as the median NRS of each region of interest (n = 481), the AUC was 95.1%. We then developed a patient-level model based on the percentage of cells with an NRS ≥ 0.5. The prediction performance showed AUC of 97.7% among the 80% (n = 23 patient) training set and with the cutoff of 61% positive cells achieved 100% sensitivity and 91.7% specificity. When applying the 61% cutoff to the 20% test set patients, the model achieved 100% accuracy. CONCLUSIONS: Our findings may have a clinical impact with an easy, accurate, and objective biomarker from routine pathology tissue, providing an unprecedented opportunity to improve neck management decisions in early-stage OSCC patients.

10.
Cell Rep ; 37(2): 109831, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34644575

RESUMO

Spinocerebellar ataxias (SCAs) are a group of genetic diseases characterized by progressive ataxia and neurodegeneration, often in cerebellar Purkinje neurons. A SCA1 mouse model, Pcp2-ATXN1[30Q]D776, has severe ataxia in absence of progressive Purkinje neuron degeneration and death. Previous RNA-seq analyses identify cerebellar upregulation of the peptide hormone cholecystokinin (Cck) in Pcp2-ATXN1[30Q]D776 mice. Importantly, absence of Cck1 receptor (Cck1R) in Pcp2-ATXN1[30Q]D776 mice confers a progressive disease with Purkinje neuron death. Administration of a Cck1R agonist, A71623, to Pcp2-ATXN1[30Q]D776;Cck-/- and Pcp2-AXTN1[82Q] mice dampens Purkinje neuron pathology and associated deficits in motor performance. In addition, A71623 administration improves motor performance of Pcp2-ATXN2[127Q] SCA2 mice. Moreover, the Cck1R agonist A71623 corrects mTORC1 signaling and improves expression of calbindin in cerebella of AXTN1[82Q] and ATXN2[127Q] mice. These results indicate that manipulation of the Cck-Cck1R pathway is a potential therapeutic target for treatment of diseases involving Purkinje neuron degeneration.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34677626

RESUMO

PURPOSE: Abnormal CD38 expression in some hematologic malignancies, including lymphoma, has made it a biomarker for targeted therapies. Daratumumab (Dara) is the first FDA-approved CD38-specific monoclonal antibody, enabling successfully immunoPET imaging over the past years. Radiolabeled Dara however has a long blood circulation and delayed tumor uptake which can limit its applications. The focus of this study is to develop 64Cu-labeled Dara-F(ab')2 for the visualization of CD38 in lymphoma models. METHODS: F(ab')2 fragment was prepared from Dara using an IdeS enzyme and purified with Protein A beads. Western blotting, flow cytometry, and surface plasmon resonance (SPR) were performed for in vitro assay. Probes were labeled with 64Cu after the chelation of 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA). Small animal PET imaging and quantitative analysis were performed after injection of 64Cu-labeled Dara-F(ab')2, IgG-F(ab')2, and Dara for evaluation in lymphoma models. RESULTS: Flow cytometry and SPR assay proved the specific binding ability of Dara-F(ab')2 and NOTA-Dara-F(ab')2 in vitro. Radiolabeling yield of [64Cu]Cu-NOTA-Dara-F(ab')2 was over 90% and with a specific activity of 4.0 ± 0.6 × 103 MBq/µmol (n = 5). PET imaging showed [64Cu]Cu-NOTA-Dara-F(ab')2 had a rapid and high tumor uptake as early as 2 h (6.9 ± 1.2%ID/g) and peaked (9.5 ± 0.7%ID/g) at 12 h, whereas [64Cu]Cu-NOTA-Dara reached its tumor uptake peaked at 48 h (8.3 ± 1.4%ID/g, n = 4). In comparison, IgG-F(ab')2 and HBL-1 control groups found no noticeable tumor uptake. [64Cu]Cu-NOTA-Dara-F(ab')2 had significantly lower uptake in blood pool, bone, and muscle than [64Cu]Cu-NOTA-Dara and its tumor-to-blood and tumor-to-muscle ratios were significantly higher than controls. CONCLUSIONS: [64Cu]Cu-NOTA-Dara-F(ab')2 showed a rapid and high tumor uptake in CD38-positive lymphoma models with favorable imaging contrast, showing its promise as a potential PET imaging agent for future clinical applications.

12.
Nat Commun ; 12(1): 6136, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675223

RESUMO

Harnessing data to discover the underlying governing laws or equations that describe the behavior of complex physical systems can significantly advance our modeling, simulation and understanding of such systems in various science and engineering disciplines. This work introduces a novel approach called physics-informed neural network with sparse regression to discover governing partial differential equations from scarce and noisy data for nonlinear spatiotemporal systems. In particular, this discovery approach seamlessly integrates the strengths of deep neural networks for rich representation learning, physics embedding, automatic differentiation and sparse regression to approximate the solution of system variables, compute essential derivatives, as well as identify the key derivative terms and parameters that form the structure and explicit expression of the equations. The efficacy and robustness of this method are demonstrated, both numerically and experimentally, on discovering a variety of partial differential equation systems with different levels of data scarcity and noise accounting for different initial/boundary conditions. The resulting computational framework shows the potential for closed-form model discovery in practical applications where large and accurate datasets are intractable to capture.

13.
Front Med (Lausanne) ; 8: 728772, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692723

RESUMO

Background: Dyspnea is the most common presenting symptom among patients hospitalized for acute heart failure (AHF). Dyspnea relief constitutes a clinically relevant therapeutic target and endpoint for clinical trials and regulatory approval. However, there have been no widely accepted dyspnea measurement standards in AHF. By systematic review and mapping the current evidence of the applied scales, timing, and results of measurement, we hope to provide some new insights and recommendations for dyspnea measurement. Methods: PubMed, Embase, Cochrane Library, and Web of Science were searched from inception until August 27, 2020. Randomized controlled trials (RCTs) with dyspnea severity measured as the endpoint in patients with AHF were included. Results: Out of a total of 63 studies, 28 had dyspnea as the primary endpoint. The Likert scale (34, 54%) and visual analog scale (VAS) (22, 35%) were most widely used for dyspnea assessment. Among the 43 studies with detailed results, dyspnea was assessed most frequently on days 1, 2, 3, and 6 h after randomization or drug administration. Compared with control groups, better dyspnea relief was observed in the experimental groups in 21 studies. Only four studies that assessed tolvaptan compared with control on the proportion of dyspnea improvement met the criteria for meta-analyses, which did not indicate beneficial effect of dyspnea improvement on day 1 (RR: 1.16; 95% CI: 0.99-1.37; p = 0.07; I 2 = 61%). Conclusion: The applied scales, analytical approaches, and timing of measurement are in diversity, which has impeded the comprehensive evaluation of clinical efficacy of potential therapies managing dyspnea in patients with AHF. Developing a more general measurement tool established on the unified unidimensional scales, standardized operation protocol to record the continuation, and clinically significant difference of dyspnea variation may be a promising approach. In addition, to evaluate the effect of experimental therapies on dyspnea more precisely, the screening time and blinded assessment are factors that need to be considered.

15.
Huan Jing Ke Xue ; 42(11): 5250-5263, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708964

RESUMO

Dissolved organic matter(DOM) is an important component of the organic matter in the environment. This study explored the characteristics of DOM. The components and spectral characteristics of rainwater DOM were measured using Ultraviolet-visible absorption spectrum(UV-vis) and three-dimensional fluorescence spectrum in the Hebei province. The results showed significant differences for DOM molecular weight in the northern, central, and southern region; the DOM of the northern region exhibited the lowest molecular weight. Two humic-like(C1 and C4), one protein-like(C2) and one fulvic-like(C3) components were identified by parallel factor(PARAFAC) analysis. Component C2 had a significant positive correlation with components C3 and C4(P<0.001), which may have similar sources. The C2(protein-like substances) accounted for the major proportion of DOM with the average abundance 40.59%. The DOM components based on PARAFAC exhibited significantly difference between city and country regions without spatial difference, which was consistent with the result of fluorescence regional integration(FRI). The protein-like substances based on FRI were the main components, which accounted for 61.59%-89.01%. Redundancy analysis(RDA) showed that total nitrogen, nitrate, and ammonia were the main environmental factors determining the distribution of DOM. Spectral indices presented a significant difference between city and country regions. High fluorescence(FI) and biological(BIX) and low humification(HIX) values showed that summer rain exhibited the strong autochthonous and low humification characteristics, and country region have stronger autochthonous characteristics than city region. The regression analysis demonstrates that the prediction accuracy of rainwater quality parameters in city region is high. From all the results, rainwater DOM, showing strong autogenous characteristics, exhibited significant differences between city and country regions without spatial difference in Hebei. Meanwhile, it can also provide technical support for rainwater nitrogen concentration prediction based on DOM components.


Assuntos
Nitrogênio , Estações do Ano , Espectrometria de Fluorescência
16.
Front Med (Lausanne) ; 8: 720119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631744

RESUMO

Background: Diagnosing chronic pulmonary aspergillosis is a major challenge in clinical practice. The development and validation of a novel, sensitive and specific assay for diagnosing chronic pulmonary aspergillosis is urgently needed. Methods: From April 2018 to June 2019, 53 patients with chronic pulmonary aspergillosis (CPA), 32 patients with community-acquired pneumonia (CAP) and 48 healthy controls were recruited from the First Affiliated Hospital of Guangzhou Medical University. Clinical characteristics and samples were collected at enrollment. All exhaled breath samples were analyzed offline using thermal desorption single-photon ionization time-of-flight mass spectrometry; to analyze the metabolic pathways of the characteristic volatile organic compounds, serum samples were subjected to ultrahigh-performance liquid chromatography. Results: We identified characteristic volatile organic compounds in patients with chronic pulmonary aspergillosis, which mainly consisted of phenol, neopentyl alcohol, toluene, limonene and ethylbenzene. These compounds were assessed using a logistic regression model. The sensitivity and specificity were 95.8 and 96.9% for discriminating patients in the CPA group from those in the CAP group and 95.8 and 97.9% for discriminating patients in the CPA group from healthy controls, respectively. The concentration of limonene (m/z 136) correlated significantly positively with anti-Aspergillus fumigatus IgG antibody titers (r = 0.420, P < 0.01). After antifungal treatment, serum IgG and the concentration of limonene (m/z 136) decreased in the subgroup of patients with chronic pulmonary aspergillosis. Conclusions: We identified VOCs that can be used as biomarkers for differential diagnosis and therapeutic response prediction in patients with chronic pulmonary aspergillosis.

17.
J Card Surg ; 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717020

RESUMO

OBJECTIVES: This review aimed to evaluate the safety and efficacy of concomitant surgical ablation (SA) for patients with atrial fibrillation (AF) undergoing rheumatic mitral valve (MV) surgery. METHODS: A systematic search of relevant studies focusing on SA for patients with AF undergoing rheumatic MV surgery was performed. The primary outcomes included mortality, efficacy, and complications. RESULTS: Four randomized controlled trials (RCTs) and four observational studies covering 1931 patients met the inclusion criteria. In RCTs, no significant differences in reoperation for bleeding, low cardiac output syndrome, thromboembolic events, and early (risk ratio [RR], 2.07; 95% confidence intervals [CI], 0.37-11.40; p = .41) and midterm all-cause death (RR, 1.07; 95% CI, 0.40-2.88; p = .89) were noted between the SA group and the nonablation group. These results were similar to those obtained from observational studies. However, ablation was associated with a higher incidence of permanent pacemaker implantation (RR, 2.44; 95% CI, 1.15-5.18; p = .02) in observational studies but not in RCTs (RR, 2.03; 95% CI, 0.19-21.26; p = .56). Furthermore, additional SA was significantly more effective in sinus rhythm (SR) restoration than MV surgery alone at discharge and at the 12-month and 3-year follow-ups. CONCLUSIONS: Concomitant SA during rheumatic MV surgery does not increase perioperative adverse events. In addition, SA promotes considerable restoration of SR. Although some evidence exists that permanent pacemaker implantation is more common after ablation, not all studies support this notion.

19.
Foods ; 10(9)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34574255

RESUMO

The exposure of foodborne pathogens such as Salmonella enterica to a sub-lethal stress may protect bacterial cells against distinct stresses during the production of leafy greens, which can constitute potential health hazards to consumers. In this study, we evaluated how the prior exposure of S. enterica to sub-lethal food processing-related stresses influenced its subsequent persistence on baby spinach under cold (4 °C for 7 days) and temperature abuse (37 °C for 2 h + 4 °C for 7 days) conditions. We also compared the survival characteristics of pre-stressed S. enterica and Enterococcus faecium NRRL B-2354 as its surrogate on baby spinach. A cocktail of three S. enterica serovars, as well as S. Typhimurium ATCC 14028 wild type and its ΔrpoS mutant, and E. faecium NRRL B-2354, was first exposed to sub-lethal desiccation, oxidation, heat shock, and acid stresses. Afterward, baby spinach was inoculated with unstressed or pre-stressed cells at 7.0 log CFU/sample unit, followed by 7-day storage under cold and temperature abuse conditions. The unstressed S. enterica (fresh cells in sterile 0.85% saline) decreased rapidly within the first day and thereafter persisted around 5.5 log CFU/sample unit under both conditions. The desiccation-stressed S. enterica showed the highest bacterial counts (p < 0.05) compared to other conditions. The unstressed S. enterica survived better (p < 0.05) than the oxidation- and acid-stressed S. enterica, while there were no significant differences (p > 0.05) between the unstressed and heat-shocked S. enterica. Unlike the wild type, temperature abuse did not lead to the enhanced survival of the ΔrpoS mutant after exposure to desiccation stress, indicating that the rpoS gene could play a critical role in the persistence of desiccation-stressed S. enterica subjected to temperature abuse. E. faecium NRRL B-2354 was more persistent (p < 0.05) than the pre-stressed S. enterica under both conditions, suggesting its use as a suitable surrogate for pre-stressed S. enterica by providing a sufficient safety margin. Our results demonstrate the merit of considering the prior exposure of foodborne pathogens to sub-lethal stresses when validating the storage conditions for leafy greens.

20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(8): 793-799, 2021 Aug 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34565721

RESUMO

OBJECTIVES: Spinocerebellar ataxia type 2 (SCA2) is one of the most common autosomal dominant ataxias in the world. Several reports revealed that CAG repeats in some polyQ-containing genes may affect the age at onset (AAO) of patients with SCA2, however, little studies were conducted among Chinese patients with SCA2. Thus, the aim of this study is to evaluate the effect of CAG repeats on the AAO of patients with SCA2 in China. METHODS: A total of 119 patients with SCA2 were enrolled and were divided into 2 groups according to their major phenotype: 17 patients from 9 families with Parkinson's syndrome were grouped as the Parkinson's disease-SCA2 (PD-SAC2); 91 patients from 66 SCA2 families and 11 sporadic SCA2 patients were grouped as the ataxia-SCA2 (A-SCA2). Blood samples were obtained from the subjects, and the CAG repeat length in ATXN2 and other (CAG)n-containing genes was screened using fluorescent PCR. The Spearman's rank correlation between the CAG repeat length in (CAG)n-containing genes and AAO was analyzed. Regression analysis was performed to investigate whether the CAG repeat length could explain the variant of AAO. A t-test was used to compare the difference of CAG repeat length in (CAG)n-containing genes between the PD-SAC2 and A-SCA2 groups. RESULTS: The CAG repeat length in the longer allele of ATXN2 was negatively correlated with AAO of SCA2 (R=-0.251, P<0.05), and the CAG repeat length could explain 41.7% of the variation of AAO. AAO negatively correlated with the CAG repeat length in the shorter allele of ATXN7 (R=-0.251, P=0.006) or in the longer allele of TBP gene (R=-0.197, P=0.034). A tendency of delay in the AAO was also observed in patients with SCA2 carrying the CAG repeat within the ATXN3, CACNA1A, ATXN7, TBP, and RAI1. In addition, we found that the CAG repeat length in ATXN7 and ATXN2 between the A-SCA2 and the PD-SCA2 groups was significantly different (both P<0.05). CONCLUSIONS: The CAG repeat in ATXN2 is a major genetic factor for the AAO of patients with SCA2 in China. The CAG repeat length in ATXN3, CACNA1A, ATXN7, TBP, and RAI1 genes might be a potential factor associated with the AAO of SCA2. The CAG repeat in ATXN7 might be a potential factor affecting the Parkinson's syndrome in SCA2.


Assuntos
Proteínas do Tecido Nervoso , Ataxias Espinocerebelares , Idade de Início , Alelos , China/epidemiologia , Humanos , Ataxias Espinocerebelares/epidemiologia , Ataxias Espinocerebelares/genética
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