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1.
Am J Transl Res ; 16(4): 1135-1144, 2024.
Article in English | MEDLINE | ID: mdl-38715806

ABSTRACT

OBJECTIVE: To establish a cellular-level mechanical injury model for human skeletal muscle cells and investigate changes in the mechanical effect mechanism after such injuries. METHODS: The FX-5000™ Compression System was used to apply constant static mechanical pressure to human skeletal muscle cells. A factorial design analysis was conducted to discover the optimal injury model by evaluating the correlation between the amount of pressure, the duration of mechanical stimulation, and the number of days of observation. Skeletal muscle cell injury was evaluated by measuring cell metabolism, morphology, and calcium homeostasis. RESULTS: Mechanical injury was modeled as continuous pressure of 1 MPa for 2 hours with observation for 3 days. The results show that mechanical injury increased creatine kinase, intracellular Ca2+ concentration, and malondialdehyde content, decreased superoxide dismutase, and caused cell swelling and severe cytoplasmic vacuolization (all P < 0.05). CONCLUSION: This model of mechanically-injured human skeletal muscle cells provides an experimental model for the clinically common skeletal muscle injury caused by static loading pressure. It may be used to study the mechanism of action of treatment methods for mechanically injured skeletal muscle.

2.
Nature ; 628(8009): 741-745, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38658686

ABSTRACT

Extensive efforts have been undertaken to combine superconductivity and the quantum Hall effect so that Cooper-pair transport between superconducting electrodes in Josephson junctions is mediated by one-dimensional edge states1-6. This interest has been motivated by prospects of finding new physics, including topologically protected quasiparticles7-9, but also extends into metrology and device applications10-13. So far it has proven challenging to achieve detectable supercurrents through quantum Hall conductors2,3,6. Here we show that domain walls in minimally twisted bilayer graphene14-18 support exceptionally robust proximity superconductivity in the quantum Hall regime, allowing Josephson junctions to operate in fields close to the upper critical field of superconducting electrodes. The critical current is found to be non-oscillatory and practically unchanging over the entire range of quantizing fields, with its value being limited by the quantum conductance of ballistic, strictly one-dimensional, electronic channels residing within the domain walls. The system described is unique in its ability to support Andreev bound states at quantizing fields and offers many interesting directions for further exploration.

3.
J Phys Chem Lett ; 15(12): 3267-3275, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38489078

ABSTRACT

For sufficiently low biases, Ohm's law, the cornerstone of electricity, stating that current I and voltage V are proportional, is satisfied at low biases for all known systems ranging from macroscopic conductors to nanojunctions. In this study, we predict theoretically and demonstrate experimentally that in single-molecule junctions fabricated with single-layer graphene as electrodes the current at low V scales as the cube of V, thereby invalidating Ohm's law. The absence of the ohmic regime is a direct consequence of the unique band structure of the single-layer graphene, whose vanishing density of states at the Dirac points precludes electron transfer from and to the electrodes at low biases.

4.
Can J Infect Dis Med Microbiol ; 2024: 6698387, 2024.
Article in English | MEDLINE | ID: mdl-38361762

ABSTRACT

To evaluate the prevalence and quality of antimicrobial prescriptions using a Global Point Prevalence Survey (PPS) tool and help identify targets for improvement of antimicrobial prescribing and inform the development of antimicrobial stewardship activities. Antimicrobial prescriptions for inpatients staying at a hospital overnight were surveyed on one weekday in October 2018, November 2019, and November 2020. Data including basic patient information, antimicrobial drugs, quality evaluation of antimicrobial drug prescription, and the risk factors of nosocomial infection were collected from doctor network workstation. Patient information was anonymized and entered in the PPS Web application by physicians. A total of 720 patients (median age, 62 years) were surveyed. Of them, 246 (34.2%) were prescribed antimicrobials on the survey days. Hospital-wide antimicrobial use had a significantly decreasing trend (P < 0.001). The most commonly prescribed antimicrobial drugs were third-generation cephalosporins (40.5%), followed by quinolones (21.8%) and second-generation cephalosporin (12.5%). In our study, cefoperazone/sulbactam, ceftazidime, and levofloxacin were the most commonly used antimicrobials. The most common indication for antimicrobial use was pneumonia or lower respiratory tract infection (159/321, 49.5%). Antimicrobial for surgical prophylaxis represented 16.2% of the total antibiotic doses. Of those, 67.3% were administered for more than 24 h. The rate of adherence to antibiotic guidelines was 61.4%. The indications for antimicrobials were not documented in 54.5% of the prescriptions. Stop/review date was documented for 36.8% of prescriptions. The PPS tool is useful in identifying targets to enhance the quality of antimicrobial prescriptions to improve the adherence rate in hospitals. This survey can be used as a control to assess the rational application quality of antimicrobial after regular application of antimicrobial intervention.

5.
Clin Oral Implants Res ; 35(4): 427-442, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38314615

ABSTRACT

OBJECTIVE: This study aimed to synthesize zinc-incorporated nanowires structure modified titanium implant surface (Zn-NW-Ti) and explore its superior osteogenic and antibacterial properties in vitro and in vivo. MATERIALS AND METHODS: Zn-NW-Ti was synthesized via displacement reactions between zinc sulfate solutions and the titanium (Ti) surface, which was pretreated by hydrofluoric acid etching and hyperthermal alkalinization. The physicochemical properties of the Zn-NW-Ti surface were examined. Moreover, the biological effects of Zn-NW-Ti on MC3T3-E1 cells and its antibacterial property against oral pathogenic bacteria (Staphylococcus aureus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) compared with sandblasted and acid-etched Ti (SLA-Ti) and nanowires modified Ti (NW-Ti) surface were assessed. Zn-NW-Ti and SLA-Ti modified implants were inserted into the anterior extraction socket of the rabbit mandible with or without exposure to the mixed bacterial solution (S. aureus, P. gingivalis, and A. actinomycetemcomitans) to investigate the osteointegration and antibacterial performance via radiographic and histomorphometric analysis. RESULTS: The Zn-NW-Ti surface was successfully prepared. The resultant titanium surface appeared as a nanowires structure with hydrophilicity, from which zinc ions were released in an effective concentration range. The Zn-NW-Ti surface performed better in facilitating the adhesion, proliferation, and differentiation of MC3T3-E1 cells while inhibiting the colonization of bacteria compared with SLA-Ti and NW-Ti surface. The Zn-NW-Ti implant exhibited enhanced osseointegration in vivo, which was attributed to increased osteogenic activity and reduced bacterial-induced inflammation compared with the SLA-Ti implant. CONCLUSIONS: The Zn-incorporated nanowires structure modified titanium implant surface exhibited improvements in osteogenic and antibacterial properties, which optimized osteointegration in comparison with SLA titanium implant surface.


Subject(s)
Dental Implants , Nanowires , Animals , Rabbits , Titanium/pharmacology , Titanium/chemistry , Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Osseointegration , Bacteria , Zinc/chemistry , Zinc/pharmacology , Surface Properties , Osteogenesis
6.
Mol Biol Rep ; 51(1): 114, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38227268

ABSTRACT

BACKGROUND: The production of interferons (IFNs) is essential for the control of viral infections, and interferon regulatory factor 7 (IRF7) is considered as a vital regulator for the transcription of type I IFNs. Amphibians appear to possess a highly expanded type I IFN repertoire, consisting of intron-containing genes as observed in fish, and intronless genes as in other higher vertebrates. However, the knowledge on transcriptional regulatory mechanism of these two types of type I IFN genes is rather scarce in amphibians. METHODS AND RESULTS: A IRF7 gene named as Np-IRF7 was identified in Tibetan frog (Nanorana parkeri), and bioinformatic analysis revealed that the predicted protein of Np-IRF7 contains several important structural features known in IRF7. Expression analysis showed that Np-IRF7 gene was widely expressed and rapidly induced by poly(I:C) in different organs/tissues. Interestingly, luciferase reporter assay revealed that intronless IFN promoters were more effectively activated than intron-containing IFN promoter in Np-IRF7-transfected cells. Moreover, the overexpression of Np-IRF7 could induce the expression of ISGs and suppress the replication of FV3 in A6 cells. CONCLUSION: Np-IRF7 is indeed the ortholog of known IRF7, and IRF7 is structurally conserved in different lineages of vertebrates. Np-IRF7 played distinct roles in the activation of intron-containing and intronless type I IFN promoters, thus inducing the expression of interferon-stimulated antiviral effectors and providing a protection against ranavirus infection. The present research thus contributes to a better understanding of regulatory function of IRF7 in the IFN-mediated antiviral response of anuran amphibians.


Subject(s)
Interferon Regulatory Factor-7 , Interferon Type I , Animals , Humans , Interferon Regulatory Factor-7/genetics , Tibet , Anura/genetics , Introns/genetics , Interferon Type I/genetics
7.
Colloids Surf B Biointerfaces ; 234: 113691, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38070369

ABSTRACT

SEMA4D-modified titanium surfaces can indirectly regulate macrophages through endothelial cells to achieve an anti-inflammatory effect, which is beneficial for healing soft tissues around the gingival abutment. However, the mechanism of surface-induced cellular phenotypic changes in SEMA4D-modified titanium has not yet been elucidated. SEMA4D activates the RhoA signaling pathway in endothelial cells, which coordinates metabolism and cytoskeletal remodeling. This study hypothesized that endothelial cells inoculated on SEMA4D-modified titanium surfaces can direct M2 polarization of macrophages via metabolites. An indirect co-culture model of endothelial cells and macrophages was constructed in vitro, and specific inhibitors were employed. Subsequently, endothelial cell adhesion and migration, metabolic changes, Rho/ROCK1 expression, and inflammatory expression of macrophages were assessed via immunofluorescence microscopy, specific kits, qRT-PCR, and Western blotting. Moreover, an in vivo rat bilateral maxillary implant model was constructed to evaluate the soft tissue healing effect. The in vitro experiments showed that the SEMA4D group had stronger endothelial cell adhesion and migration, increased Rho/ROCK1 expression, and enhanced release of lactate. Additionally, decreased macrophage inflammatory expression was observed. In contrast, the inhibitor group partially suppressed lactate metabolism and motility, whereas increased inflammatory expression. The in vivo analyses indicated that the SEMA4D group had faster and better angiogenic and anti-inflammatory effects, especially in the early stage. In conclusion, via the Rho/ROCK1 signaling pathway, the SEMA4D-modified titanium surface promotes endothelial cell adhesion and migration and lactic acid release, then the paracrine lactic acid promotes the polarization of macrophages to M2, thus obtaining the dual effects of angiogenesis and anti-inflammation.


Subject(s)
Antigens, CD , Endothelial Cells , Semaphorins , Titanium , Rats , Animals , Titanium/pharmacology , Lactic Acid , Macrophages , Anti-Inflammatory Agents
8.
China Pharmacy ; (12): 647-652, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1013096

ABSTRACT

OBJECTIVE To sort out reform policy for basic medical insurance designated retail pharmacy (referred to as designated retail pharmacy) in China, and to provide reference for the improvement of the policy under the new situation of mutual- aid mechanism for covering outpatient bills. METHODS The policy texts on designated retail pharmacies issued by ministries and commissions of the State Council and departments directly under the State Council were collected from December 1998 to June 2023. The content analysis and social network analysis were adopted to construct a three-dimensional analytical framework based on the policy subject, the policy tool, and the policy process, in order to quantitatively analyze the policies on reforming designated retail pharmacies. RESULTS & CONCLUSIONS The reform policy of designated retail pharmacies can be roughly divided into three stages: germination, exploration and development, and in-depth promotion. The use of policy tools is dominated by environment-oriented tools, and the cooperation network of policy subjects presents a “head-body-tail” chain structure. With the advancement of policy reforms, the number of policy subjects showed a trend of decline followed by growth, the number of policy documents showed an upward trend, emphasizing the use of tools such as the construction of the pharmacist system, the flow of prescriptions, the payment of medical insurance, and the management of “dual-channels” and “outpatient co-ordination”. It is suggested that in terms of policy formulation, all policy subjects should adhere to top-level design, grasp the characteristics of the stage of policy development, and adjust the use of policy tools according to local and timely conditions; we should also strengthen cooperation and communication, improve policy formulation efficiency, achieve policy coordination, and continuously improve policies for designated retail pharmacies.

9.
Medicine (Baltimore) ; 102(49): e36348, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38065870

ABSTRACT

Dry eye disease is one of the most common eye diseases. Clinical studies have found that meibomian gland expression can effectively improve the function of meibomian glands in patients with meibomian gland dysfunction. Compared with traditional appointments, Internet appointment has advantages in treating dry eye disease. A cross-sectional study was conducted to collect 300 patients with dry eye disease through an online questionnaire. Using Pearson chi-squared test, associations between the clinical parameters and appointment mode were analyzed. Spearman-rho test was executed to compare clinical data and appointment mode for correlation analysis and relationship between score of advantages of Internet booking (SOAIB), evaluation of the effectiveness of the Internet booking (EEIB), waiting in line for medical treatment (WMT). Univariate logistic regression analysis calculated the odds ratio (OR) of appointment mode for potential correlation factors. By using Pearson chi-squared test, SOAIB (P = .005), EEIB (P = .029) and WMT (P = .041) was significantly correlated with the appointment mode. Spearman correlation coefficient displayed that appointment mode was significantly correlated with EEIB (ρ = -0.126, P = .029) and WMT (ρ = 0.118, P = .041). Univariate logistic regression and concludes that EEIB (OR = 0.183, 95%CI: 0.033-1.004, P = .05), WMT (OR = 2.543, 95%CI: 1.013-6.384, P = .047) have a clear correlation with appointment mode. Spearman correlation coefficient displayed that SOAIB was significantly correlated with EEIB (ρ = -0.247, P < .001) and WMT (ρ = 0.157, P = .006). Internet appointment can effectively reduce the waiting time for dry eye disease treatment by meibomian gland expression. Effectiveness evaluation of Internet appointments is significantly higher than traditional appointments.


Subject(s)
Dry Eye Syndromes , Meibomian Gland Dysfunction , Nursing Services , Humans , Cross-Sectional Studies , Dry Eye Syndromes/therapy , Meibomian Glands
10.
Int Microbiol ; 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38062211

ABSTRACT

Aeromonas salmonicida is the typical pathogen causing furunculosis, reported widely in salmonids. Because of multiple serotypes, the control of A. salmonicida-caused disease has increasingly received much attention. Recently, A. salmonicida infection was reported in non-salmonid fish species. Here, a pathogenic A. salmonicida, named as As-s, was isolated from cultured snakehead (Channa argus) in a local fish farm in Shandong, China. As-s displayed clear hemolysis, amylase, and positive catalase activities, and grew at a wide range of temperatures (10-37 °C) and pH values (5.5-8.5). As-s was highly sensitive to cefuroxime sodium, ceftriaxone, ceftazidime, piperacillin, and cefoperazone and also apparently sensitive to chloramphenicol, erythromycin, and 25% cinnamaldehyde. The Virulence array protein gene cloning' results suggested that As-s has this gene compared with the other two vapA-containing strains, despite a close relationship of these strains via phylogenetic analysis. Severe ulcers on skin, muscle, and abnormal liver, and hemorrhage in pectoral/ventral fins and anal region were observed, and exophthalmos were also noticed in infected juvenile snakehead, as well as necrosis and infiltration of blood cells emerged in the internal organs using pathological section. In addition, As-s caused high mortality in snakehead, consistently with its immune gene response. This study reports the first isolation of vapA-absent A. salmonicida in snakehead.

12.
Zhongguo Zhong Yao Za Zhi ; 48(11): 2876-2895, 2023 Jun.
Article in Chinese | MEDLINE | ID: mdl-37381950

ABSTRACT

Microbial transformation is an efficient enzymatic approach for the structural modification of exogenous compounds to obtain derivatives. Compared with traditional chemical synthesis, the microbial transformation has in fact the undoubtable advantages of strong region-and stereo-selectivity, and a low environmental and economic impact on the production process, which can achieve the reactions challenging to chemical synthesis. Because microbes are equipped with a broad-spectrum of enzymes and therefore can metabolize various substrates, they are not only a significant route for obtaining novel active derivatives, but also an effective tool for mimicking mammal metabolism in vitro. Artemisinin, a sesquiterpene with a peroxy-bridged structure serving as the main active functional group, is a famous antimalarial agent discovered from Artemisia annua L. Some sesquiterpenoids, such as dihydroartemisinin, artemether, and arteether, have been developed on the basis of artemisinin, which have been successfully marketed and become the first-line antimalarial drugs recommended by WHO. As revealed by pharmacological studies, artemisinin and its derivatives have exhibited extensive biological activities, including antimalarial, antitumor, antiviral, anti-inflammatory, and immunomodulatory. As an efficient approach for structural modification, microbial transformation of artemisinin and its derivatives is an increasingly popular strategy that attracts considerable attention recently, and numerous novel derivatives have been discovered. Herein, this paper reviewed the microbial transformation of artemisinin and its artemisinin, including microbial strains, culture conditions, product isolation and yield, and biological activities, and summarized the advances in microbial transformation in obtaining active derivatives of artemisinin and the simulation of in vivo metabolism of drugs.


Subject(s)
Antimalarials , Artemisinins , Animals , Antimalarials/pharmacology , Antiviral Agents , Artemether , Mammals
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(6): 595-599, 2023 Jun 15.
Article in Chinese | MEDLINE | ID: mdl-37382128

ABSTRACT

OBJECTIVES: To study the clinical features of children with febrile seizures after Omicron variant infection. METHODS: A retrospective analysis was performed on the clinical data of children with febrile seizures after Omicron variant infection who were admitted to the Department of Neurology, Children's Hospital Affiliated to the Capital Institute of Pediatrics, from December 1 to 31, 2022 (during the epidemic of Omicron variant; Omicron group), and the children with febrile seizures (without Omicron variant infection) who were admitted from December 1 to 31, in 2021 were included as the non-Omicron group. Clinical features were compared between the two groups. RESULTS: There were 381 children in the Omicron group (250 boys and 131 girls), with a mean age of (3.2±2.4) years. There were 112 children in the non-Omicron group (72 boys and 40 girls), with a mean age of (3.5±1.8) years. The number of children in the Omicron group was 3.4 times that in the non-Omicron group. The proportion of children in two age groups, aged 1 to <2 years and 6-10.83 years, in the Omicron group was higher than that in the non-Omicron group, while the proportion of children in two age groups, aged 4 to <5 years and 5 to <6 years, was lower in the Omicron group than that in the non-Omicron group (P<0.05).The Omicron group had a significantly higher proportion of children with cluster seizures and status convulsion than the non-Omicron group (P<0.05). Among the children with recurrence of febrile seizures, the proportion of children aged 6-10.83 years in the Omicron group was higher than that in the non-Omicron group, while the proportion of children aged 3 years, 4 years, and 5 years in the Omicron group was lower than that in the non-Omicron group (P<0.05). CONCLUSIONS: Children with febrile seizures after Omicron variant infection tend to have a wider age range, with an increase in the proportion of children with cluster seizures and status convulsion during the course of fever.


Subject(s)
Epidemics , Epilepsy, Generalized , Seizures, Febrile , Male , Female , Humans , Child , Infant , Child, Preschool , Seizures, Febrile/etiology , Retrospective Studies , Seizures , Fever
14.
J Nanobiotechnology ; 21(1): 194, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37322478

ABSTRACT

BACKGROUND: Polarization of microglia, the resident retinal immune cells, plays important roles in mediating both injury and repair responses post-retinal ischemia-reperfusion (I/R) injury, which is one of the main pathological mechanisms behind ganglion cell apoptosis. Aging could perturb microglial balances, resulting in lowered post-I/R retinal repair. Young bone marrow (BM) stem cell antigen 1-positive (Sca-1+) cells have been demonstrated to have higher reparative capabilities post-I/R retinal injury when transplanted into old mice, where they were able to home and differentiate into retinal microglia. METHODS: Exosomes were enriched from young Sca-1+ or Sca-1- cells, and injected into the vitreous humor of old mice post-retinal I/R. Bioinformatics analyses, including miRNA sequencing, was used to analyze exosome contents, which was confirmed by RT-qPCR. Western blot was then performed to examine expression levels of inflammatory factors and underlying signaling pathway proteins, while immunofluorescence staining was used to examine the extent of pro-inflammatory M1 microglial polarization. Fluoro-Gold labelling was then utilized to identify viable ganglion cells, while H&E staining was used to examine retinal morphology post-I/R and exosome treatment. RESULTS: Sca-1+ exosome-injected mice yielded better visual functional preservation and lowered inflammatory factors, compared to Sca-1-, at days 1, 3, and 7 days post-I/R. miRNA sequencing found that Sca-1+ exosomes had higher miR-150-5p levels, compared to Sca-1- exosomes, which was confirmed by RT-qPCR. Mechanistic analysis found that miR-150-5p from Sca-1+ exosomes repressed the mitogen-activated protein kinase kinase kinase 3 (MEKK3)/JNK/c-Jun axis, leading to IL-6 and TNF-α downregulation, and subsequently reduced microglial polarization, all of which contributes to reduced ganglion cell apoptosis and preservation of proper retinal morphology. CONCLUSION: This study elucidates a potential new therapeutic approach for neuroprotection against I/R injury, via delivering miR-150-5p-enriched Sca-1+ exosomes, which targets the miR-150-5p/MEKK3/JNK/c-Jun axis, thereby serving as a cell-free remedy for treating retinal I/R injury and preserving visual functioning.


Subject(s)
Exosomes , MicroRNAs , Reperfusion Injury , Mice , Animals , Microglia/metabolism , MicroRNAs/metabolism , Exosomes/metabolism , Reperfusion Injury/metabolism , Bone Marrow Cells/metabolism
15.
Rev Sci Instrum ; 94(5)2023 May 01.
Article in English | MEDLINE | ID: mdl-37195134

ABSTRACT

The scanning superconducting quantum interference device (SQUID) fabricated on the tip of a sharp quartz pipette (SQUID-on-tip) has emerged as a versatile tool for the nanoscale imaging of magnetic, thermal, and transport properties of microscopic devices of quantum materials. We present the design and performance of a scanning SQUID-on-tip microscope in a top-loading probe of a cryogen-free dilution refrigerator. The microscope is enclosed in a custom-made vacuum-tight cell mounted at the bottom of the probe and is suspended by springs to suppress vibrations caused by the pulse tube cryocooler. Two capillaries allow for the in situ control of helium exchange gas pressure in the cell that is required for thermal imaging. A nanoscale heater is used to create local temperature gradients in the sample, which enables quantitative characterization of relative vibrations between the tip and the sample. The spectrum of the vibrations shows distinct resonant peaks with a maximal power density of about 27 nm/Hz1/2 in the in-plane direction. The performance of the SQUID-on-tip microscope is demonstrated by magnetic imaging of the MnBi2Te4 magnetic topological insulator, magnetization and current distribution imaging in a SrRuO3 ferromagnetic oxide thin film, and thermal imaging of dissipation in graphene.

16.
Nature ; 616(7956): 270-274, 2023 04.
Article in English | MEDLINE | ID: mdl-37045919

ABSTRACT

The most recognizable feature of graphene's electronic spectrum is its Dirac point, around which interesting phenomena tend to cluster. At low temperatures, the intrinsic behaviour in this regime is often obscured by charge inhomogeneity1,2 but thermal excitations can overcome the disorder at elevated temperatures and create an electron-hole plasma of Dirac fermions. The Dirac plasma has been found to exhibit unusual properties, including quantum-critical scattering3-5 and hydrodynamic flow6-8. However, little is known about the plasma's behaviour in magnetic fields. Here we report magnetotransport in this quantum-critical regime. In low fields, the plasma exhibits giant parabolic magnetoresistivity reaching more than 100 per cent in a magnetic field of 0.1 tesla at room temperature. This is orders-of-magnitude higher than magnetoresistivity found in any other system at such temperatures. We show that this behaviour is unique to monolayer graphene, being underpinned by its massless spectrum and ultrahigh mobility, despite frequent (Planckian limit) scattering3-5,9-14. With the onset of Landau quantization in a magnetic field of a few tesla, where the electron-hole plasma resides entirely on the zeroth Landau level, giant linear magnetoresistivity emerges. It is nearly independent of temperature and can be suppressed by proximity screening15, indicating a many-body origin. Clear parallels with magnetotransport in strange metals12-14 and so-called quantum linear magnetoresistance predicted for Weyl metals16 offer an interesting opportunity to further explore relevant physics using this well defined quantum-critical two-dimensional system.

17.
Colloids Surf B Biointerfaces ; 224: 113217, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36868181

ABSTRACT

Osseointegration is a prerequisite for the function of dental implants, and macrophage-dominated immune responses triggered by implantation determine the outcome of ultimate bone healing mediated by osteogenic cells. The present study aimed to develop a modified titanium (Ti) surface by covalently immobilizing chitosan-stabilized selenium nanoparticles (CS-SeNPs) to sandblasted, large grit, and acid-etched (SLA) Ti substrates and further explore its surface characteristics as well as osteogenic and anti-inflammatory activities in vitro. CS-SeNPs were successfully prepared by chemical synthesis and characterized their morphology, elemental composition, particle size, and Zeta potential. Subsequently, three different concentrations of CS-SeNPs were loaded to SLA Ti substrates (Ti-Se1, Ti-Se5, and Ti-Se10) using a covalent coupling strategy, and the SLA Ti surface (Ti-SLA) was used as a control. Scanning electron microscopy images revealed different amounts of CS-SeNPs, and the roughness and wettability of Ti surfaces were less susceptible to Ti substrate pretreatment and CS-SeNP immobilization. Besides, X-ray photoelectron spectroscopy analysis showed that CS-SeNPs were successfully anchored to Ti surfaces. The results of in vitro study showed that the four as-prepared Ti surfaces exhibited good biocompatibility, with Ti-Se1 and Ti-Se5 groups showing enhanced adhesion and differentiation of MC3T3-E1 cells compared with the Ti-SLA group. In addition, Ti-Se1, Ti-Se5, and Ti-Se10 surfaces modulated the secretion of pro-/anti-inflammatory cytokines by inhibiting the nuclear factor kappa B pathway in Raw 264.7 cells. In conclusion, doping SLA Ti substrates with a modest amount of CS-SeNPs (1-5 mM) may be a promising strategy to improve the osteogenic and anti-inflammatory activities of Ti implants.


Subject(s)
Chitosan , Nanoparticles , Selenium , Selenium/pharmacology , Titanium/pharmacology , Titanium/chemistry , Chitosan/pharmacology , Surface Properties , Osteogenesis , Anti-Inflammatory Agents/pharmacology
18.
Curr Mol Med ; 23(8): 815-824, 2023.
Article in English | MEDLINE | ID: mdl-36017862

ABSTRACT

BACKGROUND: Patients with type 2 diabetes mellitus have a high cardiovascular risk due, in part, to abnormalities of high-density lipoprotein mediated cholesterol efflux. The ATP-binding cassette A1 and G1 play a pivotal role in the regulation of cholesterol efflux. However, the regulation of these transporters in type 2 diabetes mellitus remains obscure. OBJECTIVES: This study aimed to investigate the expression of ATP-binding cassette A1 and G1 and their regulation by Liver X receptors in monocyte-derived macrophages in type 2 diabetes mellitus, and to determine whether the alteration of these transporters might affect cholesterol efflux from macrophages. METHODS: Blood was collected from type 2 diabetic patients and healthy controls. Peripheral monocytes were differentiated into macrophages. Quantitative real-time PCR, western blots, and cholesterol efflux assays were performed. The Liver X receptor and Liver X receptor element complex in the ATP-binding cassette G1 gene promoter were detected by electrophoretic mobility supershift assay. RESULTS: Macrophage ATP-binding cassette G1 expression and high density lipoproteininduced cholesterol efflux were significantly reduced in type 2 diabetic patients. However, the mRNA expression of ATP-binding cassette G1 in type 2 diabetic patients was not inhibited by Liver X receptor siRNA and the Liver X receptor- Liver X receptor element complexes remain unchanged similarly. CONCLUSION: The study suggested that the expression of ATP-binding cassette G1 and high density lipoprotein-induced cholesterol efflux in macrophages were reduced in type 2 diabetes mellitus. Impairment of cholesterol efflux and ATP-binding cassette G1 gene expression in type 2 diabetes mellitus might be regulated by a Liver X receptorindependent pathway.


Subject(s)
Diabetes Mellitus, Type 2 , Humans , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Cholesterol/metabolism , Liver X Receptors/genetics , Liver X Receptors/metabolism , Orphan Nuclear Receptors/genetics , Orphan Nuclear Receptors/metabolism , Adenosine Triphosphate , ATP Binding Cassette Transporter, Subfamily G, Member 1/genetics
19.
Chinese Journal of Pediatrics ; (12): 1124-1128, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1013234

ABSTRACT

Objective: To summarize the clinical characteristics of epileptic seizure associated with neurofibromatosis type 1 (NF1). Methods: From January 2017 to July 2023 at Children's Hospital Capital Institute of Pediatrics, medical records of patients with both NF1 and epileptic seizure were reviewed in this case series study. The clinical characteristics, treatment and prognosis were analyzed retrospectively. Results: A total of 15 patients(12 boys and 3 girls) were collected. Café-au-lait macules were observed in all 15 patients. There were 6 patients with neurodevelopmental disorders and the main manifestations were intellectual disability or developmental delay. The age at the first epileptic seizure was 2.5 (1.2, 5.5) years. There were various seizure types, including generalized tonic-clonic seizures in 8 patients, focal motor seizures in 6 patients, epileptic spasm in 4 patients, tonic seizures in 1 patient, absence in 1 patient, generalized myoclonic seizure in 1 patient and focal to bilateral tonic-clonic seizure in 1 patient. Among 14 patients whose brain magnetic resonance imaging results were available, there were abnormal signals in corpus callosum, basal ganglia, thalamus or cerebellum in 6 patients, dilated ventricles of different degrees in 3 patients, blurred gray and white matter boundary in 2 patients, agenesis of corpus callosum in 1 patient and no obvious abnormalities in the other patients. Among 13 epilepsy patients, 8 were seizure-free with 1 or 2 antiseizure medications(ASM), 1 with drug resistant epilepsy was seizure-free after left temporal lobectomy, and the other 4 patients who have received 2 to 9 ASM had persistent seizures. One patient with complex febrile convulsion achieved seizure freedom after oral administration of diazepam on demand. One patient had only 1 unprovoked epileptic seizure and did not have another seizure without taking any ASM. Conclusions: The first epileptic seizure in NF1 patients usually occurs in infancy and early childhood, with the main seizure type of generalized tonic-clonic seizure and focal motor seizure. Some patients have intellectual disability or developmental delay. Most epilepsy patients achieve seizure freedom with ASM.


Subject(s)
Male , Female , Humans , Child, Preschool , Child , Neurofibromatosis 1/diagnosis , Retrospective Studies , Intellectual Disability , Electroencephalography , Epilepsy/etiology , Seizures/etiology
20.
Chinese Journal of Pediatrics ; (12): 726-730, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1013162

ABSTRACT

Objective: To discuss the clinical and genetic features of intellectual developmental disorder with behavioral abnormalities and craniofacial dysmorphism with or without seizures (IDDBCS). Methods: The clinical and genetic records of a patient who was diagnosed with IDDBCS caused by PHF21A gene variation at Children's Hospital Capital Institute of Pediatrics in 2021 were collected retrospectively. Using " PHF21A gene" as the keyword, relevant articles were searched at CNKI, Wanfang Data and PubMed from establishment of databases to February 2023. Clinical and genetic features of IDDBCS were summarized in the combination of this case. Results: An 8 months of age boy showed overgrowth (height, weight and head circumference were all higher than the 97th percentile of children of the same age and sex) and language and motor developmental delay after birth, and gradually showed autism-like symptoms like stereotyped behavior and poor eye contact. At 8 months of age, he began to show epileptic seizures, which were in the form of a series of spastic seizures with no reaction to adrenocorticotropic hormone but a good response to vigabatrin. Physical examination showed special craniofacial appearances including a prominent high forehead, sparse eyebrows, broad nasal bridge, and downturned mouth with a tent-shaped upper lip. The patient also manifested hypotonia. Whole exome sequencing showed a de novo heterogeneous variant, PHF21A (NM_001101802.1): c.54+1G>A, and IDDBCS was diagnosed. A total of 6 articles (all English articles) were collected, involving this case and other 14 patients of IDDBCS caused by PHF21A gene variation. Clinical manifestations were intellectual disability or developmental delay (15 patients), craniofacial anomalies (15 patients), behavioral abnormalities (12 patients), seizures (9 patients), and overgrowth (8 patients). The main pathogenic variations were frameshift variations (8 patients). Conclusions: IDDBCS should be considered when patients show nervous developmental abnormalities, craniofacial anomalies, seizures and overgrowth. PHF21A gene variation detection helps to make a definite diagnosis.


Subject(s)
Male , Humans , Child , Intellectual Disability/genetics , Developmental Disabilities/genetics , Retrospective Studies , Seizures/genetics , Craniofacial Abnormalities/genetics , Histone Deacetylases/genetics
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