Association of atopy with disease severity in children with Mycoplasma pneumoniae pneumonia

BackgroundMycoplasma pneumoniae pneumonia (MPP) is common among children, but the impact of atopy on MPP severity in children is unknown. This study investigated whether atopic vs. nonatopic children had greater MPP severity.MethodsRetrospective analysis was conducted on 539 (ages 3–14 years) patients who were hospitalized in the First Affiliated Hospital of Anhui Medical University for MPP between January 2018 and December 2021, 195 were atopic and 344 were nonatopic. Of them, 204 had refractory MPP, and 335 had general MPP. And of atopic children, 94 had refractory MPP, and 101 had general MPP. Data on demographic and clinical characteristics, laboratory findings, clinical treatments were analyzed.ResultsSignificantly more boys with MPP were atopic than nonatopic (P < 0.05). More atopic (than nonatopic) children presented with prolonged fever and hospitalization, severe extra-pulmonary complications, asthma attaking, steroid and oxygen treatment, and increased IgE levels (all P < 0.05). In atopic (vs. nonatopic) children with MPP, the incidence of sputum plugs under the fiberoptic bronchoscopy and lobar pneumonia was significantly increased and required bronchoscopy-assisted and steroid therapy. Compared with nonatopic children, more atopic children developed refractory MPP (P < 0.05). Prolonged fever and hospitalization, severe extra-pulmonary complications, lymphocyte count, procalcitonin and lactate dehydrogenase levels, and percentages of atopy were all significantly higher (P < 0.05) among children with refractory MPP vs. general MPP. Moreover, Prolonged fever and hospitalization, lymphocyte count, procalcitonin and lactate dehydrogenase levels, and the treantment of steroid were all significantly higher (P < 0.05) among atopic children with refractory MPP vs. general MPP. Spearman correlation analysis showed strong associations between atopy and male sex, length of hospital stay, fever duration, IgE level, wheezing, lobar pneumonia, refractory MPP, and treatment with oxygen, hormones or bronchoscopy (P < 0.05).ConclusionsAtopy may be a risk factor for and was positively correlated with the severity of MPP in children

Effect of Cooling Process on Microstructure and Properties of Low Carbon Bainite Steel

This article used Mn-Mo-Cr-B low-carbon bainitic steel as the experimental material. The continuous cooling transformation  curve of the steel during continuous cooling was determined using a Gleeble-1500D thermal simulation test machine, and a corresponding phase transformation model for bainitic steel during continuous cooling was established. The influence of different cooling rates and final cooling temperatures on the microstructure and mechanical properties of the steel was investigated. Employing metallography, SEM, and EBSD techniques, the microstructure, crystallographic orientation, and grain boundary angle distribution of the low-carbon bainitic steel were explored, and their relationship with the steel's strength and toughness was studied. The research findings reveal that varying cooling rates and final cooling temperatures impact the phase transformation process and microstructure of the steel, consequently affecting its mechanical properties indirectly. With increasing cooling rate, the diffusion and fineness of martensite increase, and the quantity of lath bainite grows while the laths become finer. Elevated final cooling temperatures lead to larger martensitic-austenitic (MA) islands and reduced lath bainite quantity, causing the laths to become wider. Through analysis of the substructure of bainitic steel, it was determined that the bainite organization in the tested steel comprises primary austenite grains, lath packet, and lath block in succession. Lath packets are composed of lath blocks with different orientations, where lath size predominantly controls strength. Finer lath size corresponds to higher strength, and the influence of substructure on toughness is comparatively minor

Long-Term Efficacy and Safety of Human Umbilical Cord Mesenchymal Stromal Cells in Rotenone-Induced Hemiparkinsonian Rats

Several studies have shown functional improvements, neuroprotective, and neuroregenerative effects after mesenchymal stem cells transplantation to parkinsonian animal models. However, questions remain about the safety, feasibility, and long-term efficacy of this approach. In this study, we investigated migration, therapeutic, tumorigenesis, and epileptogenic effects of human umbilical cord mesenchymal stromal cells (HUMSCs) 1 year after transplantation into rotenone-induced hemiparkinsonian rats. Our data indicated that DiI-labeled HUMSCs migrated in the lesioned hemisphere, from corpus striatum (CPu) to substantia nigra. By integrating with host cells and differentiating into NSE, GFAP, Nestin, and tyrosine hydroxylase-positive cells, HUMSCs prevented 48.4% dopamine neurons from degeneration and 56.9% dopamine terminals from loss, both correlating with improvement of apomorphine-induced rotations. The CD50 and CD97 value of pentylenetetrazol and semiquantitative immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), β-catenin, C-myc, and NF-κB expression showed no significant difference between HUMSCs transplanted and untransplanted groups, whereas the expressions of Bcl-2 and P53 in the grafted CPu were upregulated by 281% and 200% compared to ungrafted CPu. The results of this long-term study suggest that HUMSCs transplantation, 1 of the most potential treatments for Parkinson's disease, is an effective and safe approach

Dietary licorice flavonoids powder improves serum antioxidant capacity and immune organ inflammatory responses in weaned piglets

Weaning often induces oxidative stress and inflammatory response in piglets. This study investigated the effects of dietary licorice flavonoids powder (LFP) supplementation on antioxidant capacity and immunity in weaned piglets. Notably, 96 Landrace × Yorkshire × Duroc (DLY) weaned piglets were randomly allocated to four treatments with 6 replicates (4 animals per replicate) and fed with diet supplementation with 0, 50, 150, and 250 mg/kg LFP, respectively. The trial lasted for 5 weeks. The results showed that dietary LFP supplementation effectively increased the liver index (P < 0.05). In addition, dietary LFP supplementation reduced serum aspartate aminotransferase activity (P < 0.01). Piglets fed with 50 mg/kg LFP decreased total cholesterol and HDL-C content in serum (P < 0.05) and increased serum alkaline phosphatase activity (P < 0.01). Similarly, supplementation with 150 mg/kg LFP elevated the activity of total antioxidant capability (T-AOC) in serum (P < 0.01) and dietary with 150 and 250 mg/kg LFP increased T-AOC activity in spleen (P < 0.01). Moreover, dietary with 150 mg/kg LFP addition enhanced (P < 0.05) the serum IgG content of piglets. Additionally, compared with the control group, dietary 250 mg/kg LFP supplementation upregulated (P < 0.05) the mRNA abundance of Interleukin (IL)-1β and monocyte chemoattractant protein 1 (MCP-1) in the spleen. Meanwhile, dietary 150 and 250 mg/kg LFP supplementation downregulated (P < 0.05) mRNA abundance of IL-10, and MCP-1 and 250 mg/kg LFP upregulated (P < 0.05) the expression of intercellular adhesion molecule 1 (ICAM-1), IL-1β, IL-6, and tumor necrosis factor α (TNF-α) in the thymus. In conclusion, LFP supplementation improved the immune function of piglets by regulating the activity of serum biochemical enzymes, improving the antioxidant capacity, and alleviating inflammation of immune organs. This study indicated that LFP is potential alternative protection against early weaned stress in piglets

Edaravone Guards Dopamine Neurons in a Rotenone Model for Parkinson's Disease

3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone), an effective free radical scavenger, provides neuroprotection in stroke models and patients. In this study, we investigated its neuroprotective effects in a chronic rotenone rat model for Parkinson's disease. Here we showed that a five-week treatment with edaravone abolished rotenone's activity to induce catalepsy, damage mitochondria and degenerate dopamine neurons in the midbrain of rotenone-treated rats. This abolishment was attributable at least partly to edaravone's inhibition of rotenone-induced reactive oxygen species production or apoptotic promoter Bax expression and its up-regulation of the vesicular monoamine transporter 2 (VMAT2) expression. Collectively, edaravone may provide novel clinical therapeutics for PD

Stereotaxical Infusion of Rotenone: A Reliable Rodent Model for Parkinson's Disease

A clinically-related animal model of Parkinson's disease (PD) may enable the elucidation of the etiology of the disease and assist the development of medications. However, none of the current neurotoxin-based models recapitulates the main clinical features of the disease or the pathological hallmarks, such as dopamine (DA) neuron specificity of degeneration and Lewy body formation, which limits the use of these models in PD research. To overcome these limitations, we developed a rat model by stereotaxically (ST) infusing small doses of the mitochondrial complex-I inhibitor, rotenone, into two brain sites: the right ventral tegmental area and the substantia nigra. Four weeks after ST rotenone administration, tyrosine hydroxylase (TH) immunoreactivity in the infusion side decreased by 43.7%, in contrast to a 75.8% decrease observed in rats treated systemically with rotenone (SYS). The rotenone infusion also reduced the DA content, the glutathione and superoxide dismutase activities, and induced alpha-synuclein expression, when compared to the contralateral side. This ST model displays neither peripheral toxicity or mortality and has a high success rate. This rotenone-based ST model thus recapitulates the slow and specific loss of DA neurons and better mimics the clinical features of idiopathic PD, representing a reliable and more clinically-related model for PD research

Development of Thiol Specific Fluorogenic Benzofurazan Derivatives for Live Cell Subcellular Organelle Thiol Imaging

Thiols (–SH) play vital and irreplaceable roles in various cellular functions in the biological system. These roles include serving as the most important antioxidant to terminate reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive electrophiles; being part of enzyme active sites; and being involved in signal transduction and cell division. Abnormality of thiols’ status has been linked to various cellular dysfunctions and diseases such as cancer, AIDS, Alzheimer\u27s disease, Parkinson\u27s disease, cardiovascular disease and others. In the biological system, thiols can be categorized structurally into two classes: protein thiols (PSH) and non-protein thiols (NPSH). PSH are mainly the cysteine residue in proteins. NPSH are mainly small molecule thiols such as cysteine, homocysteine and glutathione (GSH). The major NPSH is GSH which is present at mM concentration (1–10 mM) in the biological system and serves as the major endogenous antioxidant to maintain the intracellular redox activities, metabolism and intracellular signal transduction. Thiols are present everywhere in the biological system: intracellularly and extracellularly. They distribute at different concentration in different tissues. Intracellularly, thiols are unevenly distributed with different concentration in different subcellular organelles such as mitochondria, lysosomes, nuclei, cytosol, and cell surface. Due to the essential roles thiols play in the biological system, numerous analytical methods have been developed in detecting and quantifying thiols. However, most of these methods detect and quantify thiols through the use of homogenized biological samples. Limited methods are available to detect and quantify thiols in live cells through fluorescence microscopy. Methods for detecting and quantifying subcellular thiols in live cells through fluorescence microscopy are even more limited. Live cell imaging and quantification of thiols through fluorescence microscopy has the advantage of revealing information while thiols are in their native environment - the information cannot be revealed through the analysis of a homogenized biological sample. The major reason for a lack of analytical methods to image and quantify thiols in live cells through fluorescence microscopy is a lack of analytical reagents that can turn thiols into fluorescent specifically and sensitively with low cytotoxicity. The major objective of this dissertation work was to develop reagents that can be used to image and quantify thiols in subcellular organelles in live cells through fluorescence microscopy. This dissertation will present data demonstrating that we have successfully developed thiol specific fluorogenic reagents that can be used to image and quantify thiols in mitochondria, cell surface, and lysosomes in live cells through fluorescence microscopy. These reagents react only with thiols. They exhibit no fluorescence but becomes fluorescent after reacting with a thiol. Chapter 1 describes the design, synthesis, and characterization of thiol specific mitochondria selective fluorogenic reagents and presents the data to show how TBROS effectively imaged and quantified mitochondrial thiols in live cells through fluorescence microscopy. Chapter 2 presents the synthesis and characterization of TROX as a thiol specific fluorogenic agent to image and quantify cell surface thiols. Chapter 3 reports the development of thiol specific fluorogenic reagents for imaging and quantifying thiols in lysosomes. In chapter 4, we present preliminary data to demonstrate the ability of TROX to selectively detect cysteine in the presence of other thiols. An abnormal level of cysteine has been associated with many health issues such as cardiovascular diseases, neurological disorders, liver damage, skin lesions and growth retardation. An analytical reagent that can selectively detect cysteine will be a valuable tool in exploring the roles of cysteine in cysteine-related health issues. In conclusion, the dissertation fills a gap in the field that is a lack of reagents for imaging and quantifying thiols at subcellular level (mitochondria, cell surface, and lysosomes) in live cells through fluorescence microscopy. The dissertation also developed a reagent that can potentially detect cysteine in the presence of other thiols. The reagents developed from this dissertation will be valuable tools to aid our investigation on thiol-related cellular functions and dysfunctions

MONODENTATE BINDING OF ETHYLENEDIAMINE TO COPPER FROM PFI-ZEKE SPECTROSCOPY

Author Institution: Department of Chemistry, University of KentuckyEthylenediamine $(NH_{2}CH_{2}CH_{2}NH_{2})$, once described as ``God's gift to the coordination chemist,'' is by far the most widely studied acyclic bidentate amine in coordination chemistry. Although the ligand binds to metal atoms mainly in a bidentate mode, this study has discovered that in the gas phase it prefers a monodentate binding with a copper atom. The Cu-ethylenediamine complex was produced in a laser vaporization molecular beam and investigated by pulsed field ionization-zero electron kinetic energy (PFI-ZEKE) spectroscopy and ab initio calculations. The adiabatic ionization potential and frequencies of Cu-N stretching and Cu-ring wagging vibrations were measured from the PFI-ZEKE spectrum. Four possible isomers of the complex were predicted to be similar in energy with the MP2 calculations. The comparison of the observed and simulated spectra identified the isomer with Cu binding to single nitrogen, where the ligand is in a staggered gauche configuration with an intramolecular hydrogen bond

STUDY ON STRESS INTENSITY FACTOR OF THREE DIMENSION MODEL OF TYPEⅠCRACK IN TYPICAL LUG JOINT

On the basis of two-dimension finite element analysis,the two-dimension stress intensity factor correction coefficients of typical lug joint were obtained; Three dimension elastic plastic contact finite element model of the typical lug joint was simulated and analyzed,and the lug thickness correction factor was introduced. Based on the results of two-dimension stress intensity factor correction and three-dimension finite element stress intensity factor simulation,the plug thickness correction factors were fitted,then get the expression of stress intensity factor of three-dimension model ofⅠtype crack in typical lug joint.Finally the corresponding stress intensity factor expression was carried out to verify the accuracy,which combined with the corresponding residual strength test. The results show that the stress intensity factor calculation formula is accurate