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1.
Plant Physiol ; 194(2): 902-917, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-37934825

ABSTRACT

Maize (Zea mays L.) is one of the most important crops worldwide. Photoperiod, light quality, and light intensity in the environment can affect the growth, development, yield, and quality of maize. In Arabidopsis (Arabidopsis thaliana), cryptochromes are blue-light receptors that mediate the photocontrol of stem elongation, leaf expansion, shade tolerance, and photoperiodic flowering. However, the function of maize cryptochrome ZmCRY in maize architecture and photomorphogenic development remains largely elusive. The ZmCRY1b transgene product can activate the light signaling pathway in Arabidopsis and complement the etiolation phenotype of the cry1-304 mutant. Our findings show that the loss-of-function mutant of ZmCRY1b in maize exhibits more etiolation phenotypes under low blue light and appears slender in the field compared with wild-type plants. Under blue and white light, overexpression of ZmCRY1b in maize substantially inhibits seedling etiolation and shade response by enhancing protein accumulation of the bZIP transcription factors ELONGATED HYPOCOTYL 5 (ZmHY5) and ELONGATED HYPOCOTYL 5-LIKE (ZmHY5L), which directly upregulate the expression of genes encoding gibberellin (GA) 2-oxidase to deactivate GA and repress plant height. More interestingly, ZmCRY1b enhances lodging resistance by reducing plant and ear heights and promoting root growth in both inbred lines and hybrids. In conclusion, ZmCRY1b contributes blue-light signaling upon seedling de-etiolation and integrates light signals with the GA metabolic pathway in maize, resulting in lodging resistance and providing information for improving maize varieties.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Cryptochromes/genetics , Cryptochromes/metabolism , Arabidopsis/metabolism , Gibberellins/pharmacology , Gibberellins/metabolism , Zea mays/genetics , Zea mays/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Seedlings/metabolism , Hypocotyl , Signal Transduction , Light , Gene Expression Regulation, Plant
2.
Mol Vis ; 30: 123-136, 2024.
Article in English | MEDLINE | ID: mdl-38601019

ABSTRACT

Purpose: Danio rerio zebrafish constitute a popular model for studying lens development and congenital cataracts. However, the specific deletion of a gene with a Cre/LoxP system in the zebrafish lens is unavailable because of the lack of a lens-Cre-transgenic zebrafish. This study aimed to generate a transgenic zebrafish line in which Cre recombinase was specifically expressed in the lens. Methods: The pTol2 cryaa:Cre-polyA-cryaa:EGFP (enhanced green fluorescent protein) plasmid was constructed and co-injected with Tol2-transposase into one-to-two-cell-stage wild-type (WT) zebrafish embryos. Whole-mount in situ hybridization (ISH), tissue section, hematoxylin and eosin staining, a Western blot, a split-lamp observation, and a grid transmission assay were used to analyze the Cre expression, lens structure, and lens transparency of the transgenic zebrafish. Results: In this study, we generated a transgenic zebrafish line, zTg(cryaa:Cre-cryaa:EGFP), in which Cre recombinase and EGFP were driven by the lens-specific cryaa promoter. zTg(cryaa:Cre-cryaa:EGFP) began to express Cre and EGFP specifically in the lens at the 22 hpf stage, and this ectopic Cre could efficiently and specifically delete the red fluorescent protein (RFP) signal from the lens when zTg(cryaa:Cre-cryaa:EGFP) embryos were injected with the loxP-flanked RFP plasmid. The overexpression of Cre and EGFP did not impair zebrafish development or lens transparency. Accordingly, this zTg(cryaa:Cre-cryaa:EGFP) zebrafish line is a useful tool for gene editing, specifically with zebrafish lenses. Conclusions: We established a zTg(cryaa:Cre-cryaa:EGFP) zebrafish line that can specifically express an active Cre recombinase in lens tissues. This transgenic zebrafish line can be used as a tool to specifically manipulate a gene in zebrafish lenses.


Subject(s)
Zebrafish Proteins , Zebrafish , Animals , Zebrafish/metabolism , Animals, Genetically Modified/metabolism , Zebrafish Proteins/genetics , Zebrafish Proteins/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Integrases/genetics , Plasmids , Promoter Regions, Genetic
3.
FASEB J ; 37(3): e22832, 2023 03.
Article in English | MEDLINE | ID: mdl-36826429

ABSTRACT

The dysfunction of CRALBP, a key regulator of the visual cycle, is associated with retinitis punctata albescens characterized by night vision loss and retinal degeneration. In this paper, we find that the expression of CRALBP is regulated by heat shock protein 90 (HSP90). Inhibition of HSP90α or HSP90ß expression by using the CRISPR-Cas9 technology downregulates CRALBP's mRNA and protein expression in ARPE-19 cells by triggering the degradation of transcription factor SP1 in the ubiquitin-proteasome pathway. SP1 can bind to CRALBP's promoter, and inhibition of SP1 by its inhibitor plicamycin or siRNA downregulates CRALBP's mRNA expression. In the zebrafish, inhibition of HSP90 by the intraperitoneal injection of IPI504 reduces the thickness of the retinal outer nuclear layer and Rlbp1b mRNA expression. Interestingly, the expression of HSP90, SP1, and CRALBP is correlatedly downregulated in the senescent ARPE-19 and Pig primary RPE cells in vitro and in the aged zebrafish and mouse retinal tissues in vivo. The aged mice exhibit the low night adaption activity. Taken together, these data indicate that the HSP90-SP1 is a novel regulatory axis of CRALBP transcriptional expression in RPE cells. The age-mediated downregulation of the HSP90-SP1-CRALBP axis is a potential etiology for the night vision reduction in senior people.


Subject(s)
Vision, Ocular , Zebrafish , Mice , Animals , Swine , Zebrafish/metabolism , Down-Regulation , Retina/metabolism , Dark Adaptation , HSP90 Heat-Shock Proteins/metabolism
4.
Sensors (Basel) ; 24(2)2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38257482

ABSTRACT

This paper proposes the Lock-Position-Based RFID Adaptive Parallel Collision Tree (LAPCT) algorithm to address the issues of excessive time slots required in the identification process of collision tree algorithms for multiple tags and the high communication complexity between the reader and multiple tags. The LAPCT algorithm adopts a single-query multiple-response mechanism and dynamically divides the response sub-cycle numbers in the identification cycle based on an adaptive strategy. It uses Manchester encoding to lock collision positions and generate a common query prefix, effectively reducing the number of reader queries. This reduction in queries decreases the total number of required time slots and transmitted bits during the reader-tag communication process, thereby improving the efficiency of multiple tag recognition. Theoretical and simulation experiments demonstrate that compared to similar algorithms, the LAPCT algorithm achieves a maximum reduction of 37% in total time slots required, a maximum improvement of 30% in recognition efficiency, and a maximum reduction of 90% in communication complexity. Furthermore, with an increase in the number of tags, the performance advantages of the LAPCT algorithm become more pronounced, making it suitable for large-scale tag scenarios.

5.
Biogerontology ; 24(5): 813-827, 2023 10.
Article in English | MEDLINE | ID: mdl-36738354

ABSTRACT

SARS-Cov-2 infection, which has caused the COVID-19 global pandemic, triggers cellular senescence. In this study, we investigate the role of the SARS-COV-2 spike protein (S-protein) in regulating the senescence of RPE cells. The results showed that administration or overexpression of S-protein in ARPE-19 decreased cell proliferation with cell cycle arrest at the G1 phase. S-protein increased SA-ß-Gal positive ARPE-19 cells with high expression of P53 and P21, senescence-associated inflammatory factors (e.g., IL-1ß, IL-6, IL-8, ICAM, and VEGF), and ROS. Elimination of ROS by N-acetyl cysteine (NAC) or knocking down p21 by siRNA diminished S-protein-induced ARPE cell senescence. Both administrated and overexpressed S-protein colocalize with the ER and upregulate ER-stress-associated BIP, CHOP, ATF3, and ATF6 expression. S-protein induced P65 protein nuclear translocation. Inhibition of NF-κB by bay-11-7082 reduced S-protein-mediated expression of senescence-associated factors. Moreover, the intravitreal injection of S-protein upregulates senescence-associated inflammatory factors in the zebrafish retina. In conclusions, the S-protein of SARS-Cov-2 induces cellular senescence of ARPE-19 cells in vitro and the expression of senescence-associated cytokines in zebrafish retina in vivo likely by activating ER stress, ROS, and NF-κb. These results may uncover a potential association between SARS-cov-2 infection and development of AMD.


Subject(s)
COVID-19 , Spike Glycoprotein, Coronavirus , Animals , Humans , Spike Glycoprotein, Coronavirus/metabolism , Reactive Oxygen Species/metabolism , NF-kappa B/metabolism , Tumor Suppressor Protein p53/metabolism , Zebrafish , SARS-CoV-2/metabolism , Cellular Senescence/physiology
6.
Sensors (Basel) ; 23(5)2023 Feb 25.
Article in English | MEDLINE | ID: mdl-36904767

ABSTRACT

With the emergence of more and more computing-intensive and latency-sensitive applications, insufficient computing power and energy of user devices has become a common phenomenon. Mobile edge computing (MEC) is an effective solution to this phenomenon. MEC improves task execution efficiency by offloading some tasks to edge servers for execution. In this paper, we consider a device-to-device technology (D2D)-enabled MEC network communication model, and study the subtask offloading strategy and the transmitting power allocation strategy of users. The objective function is to minimize the weighted sum of the average completion delay and average energy consumption of users, which is a mixed integer nonlinear problem. We first propose an enhanced particle swarm optimization algorithm (EPSO) to optimize the transmit power allocation strategy. Then, we utilize the Genetic Algorithm (GA) to optimize the subtask offloading strategy. Finally, we propose an alternate optimization algorithm (EPSO-GA) to jointly optimize the transmit power allocation strategy and the subtask offloading strategy. The simulation results show that the EPSO-GA outperforms other comparative algorithms in terms of the average completion delay, average energy consumption, and average cost. In addition, no matter how the weight coefficients of delay and energy consumption change, the average cost of the EPSO-GA is the least.

7.
J Integr Plant Biol ; 65(4): 888-894, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36394421

ABSTRACT

In Arabidopsis, although studies have demonstrated that phytochrome A (phyA) and phyB are involved in blue light signaling, how blue light-activated phytochromes modulate the activity of the CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1)-SUPPRESSOR OF PHYA-105 (SPA1) E3 complex remains largely unknown. Here, we show that phyA responds to early and weak blue light, whereas phyB responds to sustainable and strong blue light. Activation of both phyA and phyB by blue light inhibits SPA1 activity. Specifically, blue light irradiation promoted the nuclear import of both phytochromes to stimulate their binding to SPA1, abolishing SPA1's interaction with LONG HYPOCOTYL 5 (HY5) to release HY5, which promoted seedling photomorphogenesis.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Phytochrome , Arabidopsis/metabolism , Phytochrome/genetics , Phytochrome/metabolism , Arabidopsis Proteins/metabolism , Light , Phytochrome A/genetics , Phytochrome A/metabolism , Cell Cycle Proteins/metabolism
8.
J Ultrasound Med ; 41(8): 1861-1872, 2022 Aug.
Article in English | MEDLINE | ID: mdl-34713919

ABSTRACT

To compare the efficacy of therapeutic ultrasound in pain relief and functional recovery in knee osteoarthritis. A comprehensive search of five databases including EMBASE, PubMed, CBM, the Cochrane Library, and Google scholar was conducted to identify relevant studies published between January 1, 2005 and December 31, 2020. Eligible randomized trials were screened for inclusion in this study. Data about the mean change of visual analogue scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and range of motion (ROM) were collected. Fourteen randomized trials covering 1080 patients with treatment durations of 2 to 24 weeks were included. Both pulsed (SMD [CI] = 1.11 [0.86, 1.36], P for heterogeneity < .00001, I2  = 18%) and continuous ultrasound (SMD [CI] = 1.18 [0.78, 1.57], P for heterogeneity < .00001, I2  = 72%) therapy had obvious pain relief effects, and high-intensity (>1.5 W/cm2 ) ultrasound seemed more effective (SMD [CI] = 1.34 [0.94, 1.73], P for heterogeneity < .00001, I2  = 35%). In addition, therapeutic ultrasound was also effective in increasing joint function by WOMAC (SMD [CI] = 8.18 [5.88, 10.48], P for heterogeneity < .00001, I2  = 59%). There was a certain degree of heterogeneity due to the differences between the subjects in the study and the ultrasound parameter settings. Our analysis confirmed that both pulsed and continuous ultrasound are effective and safe for pain relief and functional recovery of knee osteoarthritis, especially in high intensity (> 1.5 W/cm2 ). However, more high-quality randomized controlled trials will be necessary.


Subject(s)
Osteoarthritis, Knee , Ultrasonic Therapy , Analgesics , Humans , Osteoarthritis, Knee/drug therapy , Osteoarthritis, Knee/therapy , Pain/drug therapy , Pain Measurement , Treatment Outcome
9.
Water Sci Technol ; 85(1): 244-256, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35050880

ABSTRACT

As a thermally induced membrane separation process, membrane distillation (MD) has drawn more and more attention to the advantages of treating hypersaline wastewaters, especially the concentrate from the reverse osmosis (RO) process. One of the major obstacles in widespread MD application is the membrane fouling. We investigated the feasibility of direct contact membrane distillation (DCMD) for landfill leachate reverse osmosis concentrate (LFLRO) brine treatment and systematically assessed the efficiency of chemical cleaning for DCMD after processing LFLRO brine. The results showed that 80% water recovery rate was achieved when processing the LFLRO brine by DCMD, but membrane fouling occurred during the DCMD process, and manifested as the decreasing of permeate flux and the increasing of permeate conductivity. Analysis revealed that the serious flux reduction was primarily caused by the fouling layer, which consisted of organic matter and inorganic salts. Five cleaning methods were investigated for membrane cleaning, including hydrogen chloride (HCl)-sodium hydroxide (NaOH), ethylene diamine tetraacetic acid (EDTA)-NaOH, citric acid, sodium hypochlorite (NaClO) and sodium dodecyl sulphate (SDS) cleaning. Among the chemical cleaning methods investigated, the 3 wt.% SDS cleaning showed the best efficiency at recovering the performance of fouled membranes.


Subject(s)
Water Pollutants, Chemical , Distillation , Filtration , Membranes, Artificial , Osmosis , Water Pollutants, Chemical/analysis
10.
J Arthroplasty ; 34(1): 102-107, 2019 01.
Article in English | MEDLINE | ID: mdl-30342951

ABSTRACT

BACKGROUND: Total hip arthroplasty (THA) is technically challenging in patients with high dislocation of the hip secondary to suppurative arthritis. The technical difficulty is attributable to the complex hip anatomy and the potential risk of recurrent infection in these patients. This study investigated the midterm results of THA in patients with Crowe type III and IV high dislocation of the hip secondary to suppurative arthritis. METHODS: This study retrospectively reviewed 45 patients (45 hips) who underwent cementless THA with a mean quiescent infection period of 34.2 years. This study included 23 men and 22 women (mean age, 45.9 years) at the time of operation. The mean follow-up was 6.4 years. Clinical and radiographic outcomes and complications were evaluated. RESULTS: The mean Harris hip score significantly improved from 48.1 to 87.6. The modified Merle d'Aubigné-Postel, Western Ontario and McMaster Universities Arthritis Index, low back pain visual analog scale, and the 12-item short-form health survey scores also improved significantly. The mean limb length discrepancy was reduced from 38.9 mm to 6.4 mm. Postoperative dislocation occurred in 2, temporary sciatic nerve paralysis in 3, and intraoperative fracture in 2 patients. Infection and femoral stem loosening necessitated hip revision surgery in 1 patient each. CONCLUSION: THA could provide good joint function and significantly improve quality of life at the time of midterm follow-up in patients undergoing high hip dislocation secondary to suppurative arthritis. However, a relatively high incidence of complications occurred which can be treated.


Subject(s)
Arthritis, Infectious/complications , Arthroplasty, Replacement, Hip/statistics & numerical data , Hip Dislocation/surgery , Hip Joint/surgery , Adult , Aged , Arthroplasty, Replacement, Hip/methods , Female , Femur , Hip Dislocation/etiology , Hip Joint/diagnostic imaging , Humans , Joint Dislocations , Male , Middle Aged , Osteoarthritis, Hip , Postoperative Complications , Quality of Life , Radiography , Recovery of Function , Recurrence , Reoperation , Retrospective Studies , Suppuration , Time Factors , Treatment Outcome , Young Adult
11.
Nature ; 471(7337): 230-4, 2011 Mar 10.
Article in English | MEDLINE | ID: mdl-21307850

ABSTRACT

Individuals with congenital or acquired prolongation of the QT interval, or long QT syndrome (LQTS), are at risk of life-threatening ventricular arrhythmia. LQTS is commonly genetic in origin but can also be caused or exacerbated by environmental factors. A missense mutation in the L-type calcium channel Ca(V)1.2 leads to LQTS in patients with Timothy syndrome. To explore the effect of the Timothy syndrome mutation on the electrical activity and contraction of human cardiomyocytes, we reprogrammed human skin cells from Timothy syndrome patients to generate induced pluripotent stem cells, and differentiated these cells into cardiomyocytes. Electrophysiological recording and calcium (Ca(2+)) imaging studies of these cells revealed irregular contraction, excess Ca(2+) influx, prolonged action potentials, irregular electrical activity and abnormal calcium transients in ventricular-like cells. We found that roscovitine, a compound that increases the voltage-dependent inactivation of Ca(V)1.2 (refs 6-8), restored the electrical and Ca(2+) signalling properties of cardiomyocytes from Timothy syndrome patients. This study provides new opportunities for studying the molecular and cellular mechanisms of cardiac arrhythmias in humans, and provides a robust assay for developing new drugs to treat these diseases.


Subject(s)
Drug Evaluation, Preclinical/methods , Induced Pluripotent Stem Cells/pathology , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Action Potentials/drug effects , Autistic Disorder , Calcium Channels, L-Type/genetics , Calcium Channels, L-Type/metabolism , Calcium Signaling/drug effects , Cell Transdifferentiation , Cellular Reprogramming/genetics , Fibroblasts/cytology , HEK293 Cells , Humans , Long QT Syndrome/drug therapy , Long QT Syndrome/genetics , Long QT Syndrome/metabolism , Long QT Syndrome/pathology , Mutation, Missense/genetics , Myocytes, Cardiac/metabolism , Patch-Clamp Techniques , Phenotype , Purines/pharmacology , Roscovitine , Single-Cell Analysis , Syndactyly/drug therapy , Syndactyly/genetics , Syndactyly/metabolism , Syndactyly/pathology
13.
Med Mycol ; 54(1): 59-71, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26333355

ABSTRACT

Trichophyton mentagrophytes is a keratinophilic pathogenic fungus that infects both humans and animals. Subtilisins are important for T. mentagrophytes virulence, particularly when invading the epidermal barrier of the host. Subtilisin gene SUB6 belongs to a seven-member gene family (SUB1-SUB7) encoding the subtilisin serine proteases. Additionally, the SUB6 gene product Sub6, which is thought to be the major allergen Tri r2 in Trichophyton rubrum, elicits both immediate- and delayed-type hypersensitivity (DTH) reactions in humans. To assess its gene function, SUB6 was disrupted using the Agrobacterium tumefaciens-mediated transformation method. Polymerase chain reaction and Southern blot analyses were used to confirm the disruption. In vitro virulence analyses comparing the mutant with the wild-type strain showed that proteolytic activity was significantly increased in the SUB6 gene disruption strain (SUB6::hph), which corresponded to the significantly increase in MEP4 (metalloprotease gene) and SUB3 expression of SUB6::hph. The SUB6::hph -infected animals showed attenuated clinical symptoms and pathological changes, and because of the persistently high level of immunosuppressive cytokine IL-10, the increase in DTH-related cytokines IFN-γ, TNF-α and IL-12 was delayed and lower than that in animals infected with the wild-type strain. These results suggested that SUB6::hph had attenuated virulence in vivo, and that a genetically-linked regulatory effect may account for the increase in proteolytic activity and the residual pathogenicity of the mutant strain.


Subject(s)
Fungal Proteins/metabolism , Subtilisin/metabolism , Trichophyton/enzymology , Virulence Factors/metabolism , Agrobacterium tumefaciens/genetics , Animals , Disease Models, Animal , Fungal Proteins/genetics , Gene Knockout Techniques , Guinea Pigs , Subtilisin/genetics , Tinea/microbiology , Tinea/pathology , Transformation, Genetic , Trichophyton/genetics , Virulence , Virulence Factors/genetics
14.
Endocr Pract ; 22(9): 1033-9, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27124693

ABSTRACT

OBJECTIVE: Following transsphenoidal surgery (TSS), it is important to assess for and manage adrenal insufficiency (AI). The goal of this study is to assess the efficacy and safety of a glucocorticoid (GC) sparing protocol to limit GC exposure in patients undergoing TSS. METHODS: Adult patients undergoing TSS (excluding Cushing disease) with adequate adrenal function prior to surgery underwent TSS without perioperative GC coverage. Following TSS, daily morning fasting serum cortisol levels were tested. GCs were administered at stress doses for serum cortisol <5 mcg/dL, between 5 and 12 mcg/dL in the presence of clinically significant symptoms of AI, or >12 mcg/dL with severe headache, nausea or vomiting, fatigue, anorexia, or hyponatremia. The primary endpoint was the use of GCs in the immediate postoperative period. RESULTS: Of 178 subjects, GCs were administered to 80 (45%) patients for the following indications: 31.3% for serum cortisol <5 mcg/dL; 36.3% for cortisol between 5 and 12 mcg/dL accompanied by symptoms or signs of AI; 8.8% for moderate to severe postoperative hyponatremia; and 7.5% for severe headache, nausea and vomiting, fatigue, or anorexia with cortisol >12 mcg/dL. Logistic regression analysis showed that longer length of hospital stay (odds ratio [OR] 1.22, confidence interval [CI] 1.02-1.45) and the presence of new postoperative anterior pituitary hormone deficiency (OR 3.3, CI 1.26-8.67) were associated with postoperative GC use. By 12 weeks, only 14% of subjects remained on GCs. There were no adverse events related to withholding GCs. CONCLUSION: Our protocol for managing GC replacement is both safe and effective for limiting GC exposure in patients undergoing TSS. ABBREVIATIONS: AI = adrenal insufficiency CI = confidence interval FSH = follicle-stimulating hormone GC = glucocorticoid GH = growth hormone IGF-1 = insulin-like growth factor-1 IV = intravenous LH = luteinizing hormone LOS = length of hospital stay OR = odds ratio TSS = transsphenoidal surgery.


Subject(s)
Adenoma/surgery , Adrenal Insufficiency/drug therapy , Glucocorticoids/administration & dosage , Neurosurgical Procedures , Pituitary Neoplasms/surgery , Postoperative Complications/drug therapy , Sphenoid Bone/surgery , Adenoma/blood , Adolescent , Adrenal Insufficiency/blood , Adrenal Insufficiency/etiology , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Dose-Response Relationship, Drug , Female , Glucocorticoids/adverse effects , Humans , Hydrocortisone/blood , Hypopituitarism/blood , Hypopituitarism/drug therapy , Hypopituitarism/etiology , Male , Middle Aged , Neurosurgical Procedures/adverse effects , Neurosurgical Procedures/methods , Pituitary Neoplasms/blood , Postoperative Complications/blood , Postoperative Period , Retrospective Studies , Treatment Outcome , Young Adult
15.
Yi Chuan ; 37(5): 494-8, 2015 05.
Article in English | MEDLINE | ID: mdl-25998439

ABSTRACT

Bacillus anthracis, B. thuringiensis and B. cereus are members of the B. cereus group. They share high genetic similarity. Whereas plcR (Phospholipase C regulator) usually encodes a functional pleiotropic activator protein in B. cereus and B. thuringiensis isolates, a characteristic nonsense mutation is found in all B. anthracis strains investigated, making the gene dysfunctional. To study the function of PlcR in B. anthracis, we used the B. cereus CMCC63301 genome as a template and constructed a recombinant expression plasmid pBE2A-plcR, and introduced it into the B. anthracis vaccine strain A16R, and then analyzed the activity of the hemolysin and sphingomyelinase. The results showed that transformation of B. anthracis with plasmid pBE2A-plcR carrying the native B. cereus plcR gene active the expression of sphingomyelinase gene, but did not activate expression of hemolysin genes of B. anthracis A16R.


Subject(s)
Bacillus anthracis/genetics , Bacillus cereus/genetics , Bacterial Proteins/metabolism , Bacterial Vaccines/genetics , Gene Expression Regulation, Bacterial , Trans-Activators/metabolism , Bacillus anthracis/enzymology , Bacillus anthracis/growth & development , Bacillus anthracis/metabolism , Bacillus cereus/metabolism , Bacterial Proteins/genetics , Bacterial Vaccines/metabolism , Hemolysin Proteins/genetics , Hemolysin Proteins/metabolism , Sphingomyelin Phosphodiesterase/genetics , Sphingomyelin Phosphodiesterase/metabolism , Trans-Activators/genetics
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2316-9, 2015 Aug.
Article in Zh | MEDLINE | ID: mdl-26672316

ABSTRACT

The research group prepared the high-performance slag nanocrystal glass ceramics by utilizing the valuable elements of the wastes in the Chinese Bayan Obo which are characterized by their symbiotic or associated existence. In this paper, inductively coupled plasma emission spectroscopy (ICP), X-ray diffraction (XRD), Raman spectroscopy (Raman) and scanning electron microscopy (SEM) are all used in the depth analysis for the composition and structure of the samples. The experiment results of ICP, XRD and SEM showed that the principal crystalline phase of the slag nanocrystal glass ceramics containing rare earth elements is diopside, its grain size ranges from 45 to 100 nm, the elements showed in the SEM scan are basically in consistent with the component analysis of ICP. Raman analysis indicated that its amorphous phase is a three-dimensional network structure composed by the structural unit of silicon-oxy tetrahedron with different non-bridging oxygen bonds. According to the further analysis, we found that the rare earth microelement has significant effect on the network structure. Compared the nanocrystal slag glass ceramic with the glass ceramics of similar ingredients, we found that generally, the Raman band wavenumber for the former is lower than the later. The composition difference between the glass ceramics and the slag nanocrystal with the similar ingredients mainly lies on the rare earth elements and other trace elements. Therefore, we think that the rare earth elements and other trace elements remains in the slag nanocrystal glass ceramics have a significant effect on the network structure of amorphous phase. The research method of this study provides an approach for the relationship among the composition, structure and performance of the glass ceramics.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(7): 1869-72, 2014 Jul.
Article in Zh | MEDLINE | ID: mdl-25269298

ABSTRACT

In the present paper, nanocrystalline glass-ceramic of CaO-MgO-Al2O3-SiO2 system was produced by melting method. The CaO-MgO-Al2O3-SiO2 nanocrystalline glass-ceramic was measured by Raman spectroscopy in the temperature range from -190 to 310 degrees C in order to study the effect of temperature on the structure of this system nanocrystalline glass-ceramics. The results showed that different non-bridge oxygen bond silicon-oxygen tetrahedron structural unit changes are not consistent with rising temperature. Further analyses indicated that: the SiO4 tetrahedron with 2 non-bridged oxygen (Q2), the SiO4 tetrahedron with 3 non-bridged oxygen (Q(1)), which are situated at the edge of the 3-D SiO4 tetrahedrons network, and the SiO4 tetrahedron with 4 non-bridged oxygen (Q(0)), which is situated outside the 3-D network all suffered a significant influence by the temperature change, which has been expressed as: shifts towards the high wave-number, increased bond force constants, and shortened bond lengths. This paper studied the influence of temperature on CMAS system nanocrystalline glass-ceramics using variable temperature Raman technology. It provides experiment basis to the research on external environment influence on CMAS system nanocrystalline glass-ceramics materials in terms of structure and performance. In addition, the research provides experimental basis for controlling the expansion coefficient of nanocrystalline glass-ceramic of CaO-MgO-Al2O3-SiO2 system.

18.
Obstet Gynecol ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38991216

ABSTRACT

OBJECTIVE: To estimate the prevalence of post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC) after infection with SARS-CoV-2 during pregnancy and to characterize associated risk factors. METHODS: In a multicenter cohort study (NIH RECOVER [Researching COVID to Enhance Recovery]-Pregnancy Cohort), individuals who were pregnant during their first SARS-CoV-2 infection were enrolled across the United States from December 2021 to September 2023, either within 30 days of their infection or at differential time points thereafter. The primary outcome was PASC, defined as score of 12 or higher based on symptoms and severity as previously published by the NIH RECOVER-Adult Cohort, at the first study visit at least 6 months after the participant's first SARS-CoV-2 infection. Risk factors for PASC were evaluated, including sociodemographic characteristics, clinical characteristics before SARS-CoV-2 infection (baseline comorbidities, trimester of infection, vaccination status), and acute infection severity (classified by need for oxygen therapy). Multivariable logistic regression models were fitted to estimate associations between these characteristics and presence of PASC. RESULTS: Of the 1,502 participants, 61.1% had their first SARS-CoV-2 infection on or after December 1, 2021 (ie, during Omicron variant dominance); 51.4% were fully vaccinated before infection; and 182 (12.1%) were enrolled within 30 days of their acute infection. The prevalence of PASC was 9.3% (95% CI, 7.9-10.9%) measured at a median of 10.3 months (interquartile range 6.1-21.5) after first infection. The most common symptoms among individuals with PASC were postexertional malaise (77.7%), fatigue (76.3%), and gastrointestinal symptoms (61.2%). In a multivariable model, the proportion PASC positive with vs without history of obesity (14.9% vs 7.5%, adjusted odds ratio [aOR] 1.65, 95% CI, 1.12-2.43), depression or anxiety disorder (14.4% vs 6.1%, aOR 2.64, 95% CI, 1.79-3.88) before first infection, economic hardship (self-reported difficulty covering expenses) (12.5% vs 6.9%, aOR 1.57, 95% CI, 1.05-2.34), and treatment with oxygen during acute SARS-CoV-2 infection (18.1% vs 8.7%, aOR 1.86, 95% CI, 1.00-3.44) were associated with increased prevalence of PASC. CONCLUSION: The prevalence of PASC at a median time of 10.3 months after SARS-CoV-2 infection during pregnancy was 9.3% in the NIH RECOVER-Pregnancy Cohort. The predominant symptoms were postexertional malaise, fatigue, and gastrointestinal symptoms. Several socioeconomic and clinical characteristics were associated with PASC after infection during pregnancy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT05172024.

19.
Front Oncol ; 13: 1256747, 2023.
Article in English | MEDLINE | ID: mdl-38164196

ABSTRACT

Objective: Breast cancer is one of the most common causes of death among women. Statins, typically used for cholesterol management, have been hypothesized to reduce recurrence and mortality rates in breast cancer. However, this association remains a subject of debate. This study evaluates the potential impact of statins on breast cancer recurrence and mortality. Methods: A comprehensive search was conducted in the PubMed, EMBASE, and Cochrane databases for articles published up to June 2023. These articles examined the effect of statins on breast cancer recurrence and mortality both before and after diagnosis. The analysis was performed using random-effects models, calculating pooled hazard ratios (HR) and their 95% confidence intervals (CI). Results: A total of 31 cohort studies, involving 261,834 female breast cancer patients, were included in this analysis. It was found that statin use prior to diagnosis was associated with a decrease in overall mortality (HR, 0.8; 95% CI, 0.69-0.93; I2 = 77.6%; P = 0.001) and breast cancer-specific mortality (HR, 0.76; 95% CI, 0.67-0.87; I2 = 72.7%; P = 0.005). Additionally, statin use after diagnosis was observed to reduce the recurrence of breast cancer (HR, 0.71; 95% CI, 0.61-0.82; I2 = 60%; P = 0.003), overall mortality (HR, 0.81; 95% CI, 0.70-0.92; I2 = 80.7%; P < 0.001), and breast cancer-specific mortality (HR, 0.76; 95% CI, 0.67-0.86; I2 = 74.5%; P < 0.001). Conclusions: The findings of this study indicate that statin usage, both before and after breast cancer diagnosis, may be associated with reduced risks of overall and breast cancer-specific mortality, as well as lower recurrence rates.

20.
Front Microbiol ; 14: 1320853, 2023.
Article in English | MEDLINE | ID: mdl-38249462

ABSTRACT

Intensification of urban construction has gradually destroyed human habitat ecosystems. Plants, which serve as the foundation of ecosystems, require green, low-cost, and effective technologies to sustain their growth in stressful environments. A total of 286 keywords and 10 clusters from the bibliometric analysis of 529 articles (1999-2023) indicate the increasing importance of research on microbial functionality in landscape ecosystems. Phosphate solubilizing microorganisms (PSMs) also improve plant disease resistance, adaptability, and survival. PSMs are widely used to promote plant growth and improve ecological quality. They can increase the availability of phosphorus in the soil and reduce the dependence of plants on chemical fertilizers. Microorganisms regulate phosphorus as key tools in landscape ecosystems. Most importantly, in urban and rural landscape practices, PSMs can be applied to green spaces, residential landscapes, road greening, and nursery planting, which play significant roles in improving vegetation coverage, enhancing plant resistance, improving environmental quality, and mitigating the heat island effect. PSMs are also helpful in restoring the ecological environment and biodiversity of polluted areas, such as brownfields, to provide residents with a more liveable living environment. Therefore, the multiple efficacies of PSM are expected to play increasingly important roles in the construction of urban and rural landscape ecosystems.

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