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1.
Nature ; 624(7992): 564-569, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38123807

RESUMO

Medium- and high-entropy alloys (M/HEAs) mix several principal elements with near-equiatomic composition and represent a model-shift strategy for designing previously unknown materials in metallurgy1-8, catalysis9-14 and other fields15-18. One of the core hypotheses of M/HEAs is lattice distortion5,19,20, which has been investigated by different numerical and experimental techniques21-26. However, determining the three-dimensional (3D) lattice distortion in M/HEAs remains a challenge. Moreover, the presumed random elemental mixing in M/HEAs has been questioned by X-ray and neutron studies27, atomistic simulations28-30, energy dispersive spectroscopy31,32 and electron diffraction33,34, which suggest the existence of local chemical order in M/HEAs. However, direct experimental observation of the 3D local chemical order has been difficult because energy dispersive spectroscopy integrates the composition of atomic columns along the zone axes7,32,34 and diffuse electron reflections may originate from planar defects instead of local chemical order35. Here we determine the 3D atomic positions of M/HEA nanoparticles using atomic electron tomography36 and quantitatively characterize the local lattice distortion, strain tensor, twin boundaries, dislocation cores and chemical short-range order (CSRO). We find that the high-entropy alloys have larger local lattice distortion and more heterogeneous strain than the medium-entropy alloys and that strain is correlated to CSRO. We also observe CSRO-mediated twinning in the medium-entropy alloys, that is, twinning occurs in energetically unfavoured CSRO regions but not in energetically favoured CSRO ones, which represents, to our knowledge, the first experimental observation of correlating local chemical order with structural defects in any material. We expect that this work will not only expand our fundamental understanding of this important class of materials but also provide the foundation for tailoring M/HEA properties through engineering lattice distortion and local chemical order.

2.
Nature ; 614(7947): 262-269, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36755171

RESUMO

Carbon dioxide electroreduction facilitates the sustainable synthesis of fuels and chemicals1. Although Cu enables CO2-to-multicarbon product (C2+) conversion, the nature of the active sites under operating conditions remains elusive2. Importantly, identifying active sites of high-performance Cu nanocatalysts necessitates nanoscale, time-resolved operando techniques3-5. Here, we present a comprehensive investigation of the structural dynamics during the life cycle of Cu nanocatalysts. A 7 nm Cu nanoparticle ensemble evolves into metallic Cu nanograins during electrolysis before complete oxidation to single-crystal Cu2O nanocubes following post-electrolysis air exposure. Operando analytical and four-dimensional electrochemical liquid-cell scanning transmission electron microscopy shows the presence of metallic Cu nanograins under CO2 reduction conditions. Correlated high-energy-resolution time-resolved X-ray spectroscopy suggests that metallic Cu, rich in nanograin boundaries, supports undercoordinated active sites for C-C coupling. Quantitative structure-activity correlation shows that a higher fraction of metallic Cu nanograins leads to higher C2+ selectivity. A 7 nm Cu nanoparticle ensemble, with a unity fraction of active Cu nanograins, exhibits sixfold higher C2+ selectivity than the 18 nm counterpart with one-third of active Cu nanograins. The correlation of multimodal operando techniques serves as a powerful platform to advance our fundamental understanding of the complex structural evolution of nanocatalysts under electrochemical conditions.

3.
Nature ; 592(7852): 60-64, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33790443

RESUMO

Amorphous solids such as glass, plastics and amorphous thin films are ubiquitous in our daily life and have broad applications ranging from telecommunications to electronics and solar cells1-4. However, owing to the lack of long-range order, the three-dimensional (3D) atomic structure of amorphous solids has so far eluded direct experimental determination5-15. Here we develop an atomic electron tomography reconstruction method to experimentally determine the 3D atomic positions of an amorphous solid. Using a multi-component glass-forming alloy as proof of principle, we quantitatively characterize the short- and medium-range order of the 3D atomic arrangement. We observe that, although the 3D atomic packing of the short-range order is geometrically disordered, some short-range-order structures connect with each other to form crystal-like superclusters and give rise to medium-range order. We identify four types of crystal-like medium-range order-face-centred cubic, hexagonal close-packed, body-centred cubic and simple cubic-coexisting in the amorphous sample, showing translational but not orientational order. These observations provide direct experimental evidence to support the general framework of the efficient cluster packing model for metallic glasses10,12-14,16. We expect that this work will pave the way for the determination of the 3D structure of a wide range of amorphous solids, which could transform our fundamental understanding of non-crystalline materials and related phenomena.

4.
Hepatology ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38436992

RESUMO

BACKGROUND AND AIMS: A single-nation study reported that pretreatment HBV viral load is associated with on-treatment risk of HCC in patients who are HBeAg-positive without cirrhosis and with chronic hepatitis B initiating antiviral treatment. We aimed to validate the association between baseline HBV viral load and on-treatment HCC risk in a larger, multinational cohort. APPROACH AND RESULTS: Using a multinational cohort from Korea, Hong Kong, and Taiwan involving 7545 adult patients with HBeAg-positive, without cirrhosis and with chronic hepatitis B who started entecavir or tenofovir treatment with baseline HBV viral load ≥5.00 log 10 IU/mL, HCC risk was estimated by baseline viral load. HBV viral load was analyzed as a categorical variable. During continuous antiviral treatment (median, 4.28 y), HCC developed in 200 patients (incidence rate, 0.61 per 100 person-years). Baseline HBV DNA level was independently associated with on-treatment HCC risk in a nonlinear pattern. HCC risk was lowest with the highest baseline viral load (≥8.00 log 10 IU/mL; incidence rate, 0.10 per 100 person-years), but increased sharply as baseline viral load decreased. The adjusted HCC risk was 8.05 times higher (95% CI, 3.34-19.35) with baseline viral load ≥6.00 and <7.00 log 10 IU/mL (incidence rate, 1.38 per 100 person-years) compared with high (≥8.00 log 10 IU/mL) baseline viral load ( p <0.001). CONCLUSIONS: In a multinational cohort of adult patients with HBeAg-positive without cirrhosis and with chronic hepatitis B, baseline HBV viral load was significantly associated with HCC risk despite antiviral treatment. Patients with the highest viral load who initiated treatment had the lowest long-term risk of HCC development.

5.
Nature ; 570(7762): 500-503, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31243385

RESUMO

Nucleation plays a critical role in many physical and biological phenomena that range from crystallization, melting and evaporation to the formation of clouds and the initiation of neurodegenerative diseases1-3. However, nucleation is a challenging process to study experimentally, especially in its early stages, when several atoms or molecules start to form a new phase from a parent phase. A number of experimental and computational methods have been used to investigate nucleation processes4-17, but experimental determination of the three-dimensional atomic structure and the dynamics of early-stage nuclei has been unachievable. Here we use atomic electron tomography to study early-stage nucleation in four dimensions (that is, including time) at atomic resolution. Using FePt nanoparticles as a model system, we find that early-stage nuclei are irregularly shaped, each has a core of one to a few atoms with the maximum order parameter, and the order parameter gradient points from the core to the boundary of the nucleus. We capture the structure and dynamics of the same nuclei undergoing growth, fluctuation, dissolution, merging and/or division, which are regulated by the order parameter distribution and its gradient. These experimental observations are corroborated by molecular dynamics simulations of heterogeneous and homogeneous nucleation in liquid-solid phase transitions of Pt. Our experimental and molecular dynamics results indicate that a theory beyond classical nucleation theory1,2,18 is needed to describe early-stage nucleation at the atomic scale. We anticipate that the reported approach will open the door to the study of many fundamental problems in materials science, nanoscience, condensed matter physics and chemistry, such as phase transition, atomic diffusion, grain boundary dynamics, interface motion, defect dynamics and surface reconstruction with four-dimensional atomic resolution.

6.
Proc Natl Acad Sci U S A ; 119(13): e2119883119, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35312369

RESUMO

SignificanceWe present a groundbreaking advance in completely nonprecious hydrogen fuel cell technologies achieving a record power density of 200 mW/cm2 with Ni@CNx anode and Co-Mn cathode. The 2-nm CNx coating weakens the O-binding energy, which effectively mitigates the undesirable surface oxidation during hydrogen oxidation reaction (HOR) polarization, leading to a stable fuel cell operation for Ni@CNx over 100 h at 200 mA/cm2, superior to a Ni nanoparticle counterpart. Ni@CNx exhibited a dramatically enhanced tolerance to CO relative to Pt/C, enabling the use of hydrogen gas with trace amounts of CO, critical for practical applications. The complete removal of precious metals in fuel cells lowers the catalyst cost to virtually negligible levels and marks a milestone for practical alkaline fuel cells.

7.
Genomics ; 116(5): 110882, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857814

RESUMO

The investigation of dwarfing rootstocks for the establishment of high-generation seed orchards is a prospective avenue of research. In this investigation, Pinus massoniana, Pinus yunnanensis var. pygmaea (P. pygmaea), and P. elliottii seedlings were used as rootstocks for grafting with P. massoniana scions. Grafting P. massoniana onto P. pygmaea rootstock resulted in observable phenotypic alterations in lateral branches, apical buds, and needle length. Certain characteristic metabolites of rootstocks, such as fatty acyls, pregnenolones, steroids, and steroid derivatives, were found to be highly expressed in scions after grafting. RNA-seq analysis revealed MYB-related, SBP, and bHLH demonstrating a significant positive correlation, while C2H2 and Orphans exhibited negative correlations with the differential intensity of metabolites related to lipids and lipid-like molecules. This study offers valuable insights for the establishment of rootstock breeding programs.

8.
BMC Genomics ; 25(1): 281, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493093

RESUMO

Drought stress can significantly affect plant growth, development, and yield. Fewer comparative studies have been conducted between different species of pines, particularly involving Pinus yunnanensis var. pygmaea (P. pygmaea). In this study, the physiological indices, photosynthetic pigment and related antioxidant enzyme changes in needles from P. pygmaea, P. elliottii and P. massoniana under drought at 0, 7, 14, 21, 28 and 35 d, as well as 7 days after rehydration, were measured. The PacBio single-molecule real-time (SMRT) and Illumina RNA sequencing were used to uncover the gene expression differences in P. pygmaea under drought and rehydration conditions. The results showed that the total antioxidant capacity (TAOC) of P. pygmaea was significantly higher than P. massoniana and P. elliottii. TAOC showed a continuous increase trend across all species. Soluble sugar (SS), starch content and non-structural carbohydrate (NSC) of all three pines displayed a "W" pattern, declining initially, increasing, and then decreasing again. P. pygmaea exhibits stronger drought tolerance and greater recovery ability under prolonged drought conditions. Through the PacBio SMRT-seq, a total of 50,979 high-quality transcripts were generated, and 6,521 SSR and 5,561 long non-coding RNAs (LncRNAs) were identified. A total of 2310, 1849, 5271, 5947, 7710, and 6854 differentially expressed genes (DEGs) were identified compared to the control (Pp0D) in six pair-wise comparisons of treatment versus control. bHLH, NAC, ERF, MYB_related, C3H transcription factors (TFs) play an important role in drought tolerance of P. pygmaea. KEGG enrichment analysis and Gene set enrichment analysis (GSEA) analysis showed that P. pygmaea may respond to drought by enhancing metabolic processes such as ABA signaling pathway, alpha-linolenic acid. Weighted gene co-expression network analysis (WGCNA) revealed GST, CAT, LEC14B, SEC23 were associated with antioxidant enzyme activity and TAOC. This study provides a basis for further research on drought tolerance differences among coniferous species.


Assuntos
Secas , Pinus , Antioxidantes , Perfilação da Expressão Gênica/métodos , Transcriptoma , Pinus/genética , Carboidratos , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética
9.
J Am Chem Soc ; 146(7): 4680-4686, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324776

RESUMO

Precious-metal-free spinel oxide electrocatalysts are promising candidates for catalyzing the oxygen reduction reaction (ORR) in alkaline fuel cells. In this theory-driven study, we use joint density functional theory (JDFT) in tandem with supporting electrochemical measurements to identify a novel theoretical pathway for the ORR on cubic Co3O4 nanoparticle electrocatalysts, which aligns more closely with experimental results than previous models. The new pathway employs the cracked adsorbates *(OH)(O) and *(OH)(OH), which, through hydrogen bonding, induce spectator surface *H. This results in an onset potential closely matching experimental values, in stark contrast to the traditional ORR pathway, which keeps adsorbates intact and overestimates the onset potential by 0.7 V. Finally, we introduce electrochemical strain spectroscopy (ESS), a groundbreaking strain analysis technique. ESS combines ab initio calculations with experimental measurements to validate the proposed reaction pathways and pinpoint rate-limiting steps.

10.
Chembiochem ; : e202400249, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819725

RESUMO

Herein, we report the finding that a naturally sunflower pollen-derived microspheres (HSECs) with hierarchical structures can selectively absorb polyC and polyA with high efficiency and affinity. HSECs exhibit the capability to selectively absorb polyC and polyA ssDNA under neutral and acidic conditions. It has been observed that the presence of metal cations, specifically Ca2+, enhances the absorption efficiency of HSECs. Mechanically, this absorption phenomenon can be attributed to both electrostatic interactions and cation-π interactions. Such an appealing property enables the functionalization of HSECs for broad potential biomedical applications, such as microRNA detection.

11.
Anal Biochem ; 685: 115409, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38006953

RESUMO

Aptamers are widely used in various biomedical areas as novel molecular recognition elements, however, short single-stranded DNA (ssDNA) or RNA oligonucleotides are easily degraded by nucleases in biological fluids. This problem can be solved by circularizing aptamers with circular ligases. Herein, a moderately thermostable ssDNA ligase was expressed and purified. The purified ligase showed good circularization activity for different length substrates and much higher circularization efficiency than T4 RNA ligase 1. Biochemical characterization revealed that the enzyme showed optimal circularization activity at pH 7.5 and 50 ᵒC. Mn2+ and Mg2+ increased enzyme circularization activity, with Mn2+ having higher activity than Mg2+. The optimal concentrations of Mn2+ and ligase were 1.25-2.5 mM and 0.02 nM, respectively. The kinetic parameters Km, Vmax and Kcat of ssDNA ligase were 1.16 µM, 10.71 µM/min, and 10.7 min-1, respectively. The ssDNA ligase efficiency was nucleotide-dependent, and 5'-G and 3'-T were the most ligase-favored terminal nucleotides. In addition, the affinity and stability of the circular aptamer were determined. The affinity constant (KD) was 4.9 µM, and the stability increased compared to its linear form. Molecular docking results showed that the circular aptamer bound to the target via two hydrogen bonds. This study provides a simple and efficient aptamer circularization modification method for improving aptamer stability and expanding its applications.


Assuntos
Aptâmeros de Nucleotídeos , DNA de Cadeia Simples , Ligases/metabolismo , Simulação de Acoplamento Molecular , RNA/química , Aptâmeros de Nucleotídeos/química
12.
Ann Bot ; 134(1): 71-84, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38470192

RESUMO

BACKGROUND AND AIMS: Niche differentiation is a crucial issue in speciation. Although it has a well-known role in adaptive processes of hybrid angiosperms, it is less understood in hybrid ferns. Here, we investigate whether an intermediate ecological niche of a fern hybrid is a novel adaptation that provides insights into fern hybrid speciation. METHODS: Pteris fauriei (Pteridaceae) is a natural hybrid fern, occurring in environments between its parent species. The maternal Pteris minor is found in sunny areas, but the habitat of the paternal Pteris latipinna is shady. We combined data from morphology, leaf anatomy and photosynthetic traits to explore adaptation and differentiation, along with measuring the environmental features of their niches. We also performed experiments in a common garden to understand ecological plasticity. KEY RESULTS: The hybrid P. fauriei was intermediate between the parent species in stomatal density, leaf anatomical features and photosynthetic characteristics in both natural habitats and a common garden. Interestingly, the maternal P. minor showed significant environmental plasticity and was more similar to the hybrid P. fauriei in the common garden, suggesting that the maternal species experiences stress in its natural habitats but thrives in environments similar to those of the hybrid. CONCLUSIONS: Based on the similar niche preferences of the hybrid and parents, we propose hybrid superiority. Our results indicate that the hybrid P. fauriei exhibits greater fitness and can compete with and occupy the initial niches of the maternal P. minor. Consequently, we suggest that the maternal P. minor has experienced a niche shift, elucidating the pattern of niche differentiation in this hybrid group. These findings offer a potential explanation for the frequent occurrence of hybridization in ferns and provide new insights into fern hybrid speciation, enhancing our understanding of fern diversity.


Assuntos
Ecossistema , Hibridização Genética , Fenótipo , Pteris , Pteris/fisiologia , Pteris/anatomia & histologia , Pteris/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Especiação Genética , Fotossíntese/fisiologia , Gleiquênias/fisiologia , Gleiquênias/anatomia & histologia , Adaptação Fisiológica
13.
Helicobacter ; 29(1): e13049, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558496

RESUMO

BACKGROUND: Helicobacter pylori infection is primarily acquired in childhood and can lead to peptic ulcer diseases and gastric cancer. The prevalence of H. pylori infection varies widely in different countries. The aim of this study was to explore the change of pediatric H. pylori seroprevalence in the past two decades and to investigate the risk factors for pediatric H. pylori seropositivity in southern Taiwan. MATERIALS AND METHODS: This study enrolled children aged 7-12 years in Tainan City in 2018 and compared the result with our previous data in 1998, 2005, and 2010. Parents of the participants were invited to fill out questionnaires, including information of personal history, family history of peptic ulcer diseases, annual household income, and source of drinking water. Blood samples were analyzed for anti-H. pylori IgG by enzyme-linked immunosorbent assay. RESULTS: A total of 391, 629, 618, and 488 elementary school students in Tainan City were enrolled in 1998, 2005, 2010, and 2018, respectively. There was a significant decline in H. pylori seroprevalence from 9.2% in 1998, 7.8% in 2005, 6.2% in 2010 to 4.7% in 2018 (p < 0.001). Neither gender difference nor age difference was found in H. pylori seropositivity in each year of enrollment. Low household income was significantly associated with pediatric H. pylori seropositivity. CONCLUSIONS: The seroprevalence of H. pylori infection among elementary schoolchildren has remarkably declined in southern Taiwan in the past two decades. Low household income was a risk factor for pediatric H. pylori seropositivity.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Úlcera Péptica , Criança , Humanos , Infecções por Helicobacter/epidemiologia , Estudos Soroepidemiológicos , Taiwan/epidemiologia , Seguimentos , Anticorpos Antibacterianos , Úlcera Péptica/epidemiologia
14.
Chem Rev ; 122(6): 6117-6321, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35133808

RESUMO

Hydrogen energy-based electrochemical energy conversion technologies offer the promise of enabling a transition of the global energy landscape from fossil fuels to renewable energy. Here, we present a comprehensive review of the fundamentals of electrocatalysis in alkaline media and applications in alkaline-based energy technologies, particularly alkaline fuel cells and water electrolyzers. Anion exchange (alkaline) membrane fuel cells (AEMFCs) enable the use of nonprecious electrocatalysts for the sluggish oxygen reduction reaction (ORR), relative to proton exchange membrane fuel cells (PEMFCs), which require Pt-based electrocatalysts. However, the hydrogen oxidation reaction (HOR) kinetics is significantly slower in alkaline media than in acidic media. Understanding these phenomena requires applying theoretical and experimental methods to unravel molecular-level thermodynamics and kinetics of hydrogen and oxygen electrocatalysis and, particularly, the proton-coupled electron transfer (PCET) process that takes place in a proton-deficient alkaline media. Extensive electrochemical and spectroscopic studies, on single-crystal Pt and metal oxides, have contributed to the development of activity descriptors, as well as the identification of the nature of active sites, and the rate-determining steps of the HOR and ORR. Among these, the structure and reactivity of interfacial water serve as key potential and pH-dependent kinetic factors that are helping elucidate the origins of the HOR and ORR activity differences in acids and bases. Additionally, deliberately modulating and controlling catalyst-support interactions have provided valuable insights for enhancing catalyst accessibility and durability during operation. The design and synthesis of highly conductive and durable alkaline membranes/ionomers have enabled AEMFCs to reach initial performance metrics equal to or higher than those of PEMFCs. We emphasize the importance of using membrane electrode assemblies (MEAs) to integrate the often separately pursued/optimized electrocatalyst/support and membranes/ionomer components. Operando/in situ methods, at multiscales, and ab initio simulations provide a mechanistic understanding of electron, ion, and mass transport at catalyst/ionomer/membrane interfaces and the necessary guidance to achieve fuel cell operation in air over thousands of hours. We hope that this Review will serve as a roadmap for advancing the scientific understanding of the fundamental factors governing electrochemical energy conversion in alkaline media with the ultimate goal of achieving ultralow Pt or precious-metal-free high-performance and durable alkaline fuel cells and related technologies.


Assuntos
Fontes de Energia Elétrica , Prótons , Hidrogênio/química , Oxigênio/química , Água
15.
Eur J Epidemiol ; 39(2): 207-218, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198037

RESUMO

The China Surgery and Anaesthesia Cohort (CSAC) study was launched in July 2020 and is an ongoing prospective cohort study recruiting patients aged 40-65 years who underwent elective surgeries with general anaesthesia across four medical centres in China. The general objective of the CSAC study is to improve our understanding of the complex interaction between environmental and genetic components as well as to determine their effects on a wide range of interested surgery/anaesthesia-related outcomes. To achieve this goal, we collected enriched phenotypic data, e.g., sociodemographic characteristics, lifestyle factors, perioperative neuropsychological changes, anaesthesia- and surgery-related complications, and medical conditions, at recruitment, as well as through both active (at 1, 3, 7 days and 1, 3, 6, 12 months after surgery) and passive (for more than 1 year after surgery) follow-up assessments. We also obtained omics data from blood samples. In addition, COVID-19-related information was collected from all participants since January 2023, immediately after COVID-19 restrictions were eased in China. As of July 18, 2023, 12,766 participants (mean age = 52.40 years, 57.93% were female) completed baseline data collection (response rate = 94.68%), among which approximately 70% donated blood and hair samples. The follow-up rates within 12 months after surgery were > 92%. Our initial analyses have demonstrated the incidence of and risk factors for chronic postsurgical pain (CPSP) and postoperative cognitive dysfunction (POCD) among middle-aged Chinese individuals, which may prompt further mechanistic exploration and facilitate the development of effective interventions for preventing those conditions. Additional studies, such as genome-wide association analyses for identifying the genetic determinants of CPSP and POCD, are ongoing, and their findings will be released in the future.


Assuntos
Anestesia , COVID-19 , Pessoa de Meia-Idade , Humanos , Feminino , Masculino , Estudo de Associação Genômica Ampla , Estudos Prospectivos , Anestesia/efeitos adversos , COVID-19/epidemiologia , China/epidemiologia
16.
Oral Dis ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568959

RESUMO

BACKGROUND: Emerging evidence supports the association between periodontitis and depression, although the mechanisms are unclear. This study investigated the role of SorCS2 in the pathogenesis of periodontitis-induced depression. MATERIALS AND METHODS: An experimental periodontitis model was established using SorCS2 knockout mice and their wild-type littermates, and depression-like behaviour was evaluated. The expression of proBDNF signalling, neuronal activity, and glutamate-associated signalling pathways were further measured by western blotting and immunofluorescence. In addition, neuroinflammatory status, astrocytic and microglial markers, and the expression of corticosterone-related factors were measured by immunofluorescence, western blotting, and enzyme-linked immunosorbent assays. RESULTS: SorCS2 deficiency alleviated periodontitis-induced depression-like behaviour in mice. Further results suggested that SorCS2 deficiency downregulated the expression of pro-BDNF and glutamate signalling and restored neuronal activities in mice with periodontitis. Neuroinflammation in the mouse hippocampus was triggered by experimental periodontitis but was not affected by SorCS2 deficiency. The levels of corticosterone and the expression of glucocorticoid receptors were also not altered. CONCLUSION: Our study, for the first time, reveals the critical role of SorCS2 in the pathogenesis of periodontitis-induced depression. The underlying mechanism involves proBDNF and glutamate signalling in the hippocampus, providing a novel therapeutic target for periodontitis-associated depression.

17.
BMC Ophthalmol ; 24(1): 63, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350933

RESUMO

BACKGROUND: Macular hole (MH) development following scleral buckling (SB) surgery for rhegmatogenous retinal detachment (RRD) repair is rare. This study presents both full-thickness MH (FTMH) and lamellar MH (LMH) cases following SB for the treatment of RRD. METHODS: Clinical records of patients undergoing SB surgery for treatment of RRD at the Xi'an People's Hospital (Xi'an Fourth Hospital) from January 2016 to December 2021 were reviewed, and cases with postoperative MH were selected. Clinical features and follow-up data were summarised, and possible causes were analysed. RESULTS: Among 483 identified cases (483 eyes), four eyes (three male patients, one female patient) had postoperative MH, with prevalence, mean age, and mean axial length of 0.83%, 43.5 ± 10.66 years, and 29.13 ± 3.80 mm, respectively. All patients did not undergo subretinal fluid (SRF) drainage. The mean time for detecting MH was 26 ± 15.5 days postoperatively. Macula-off RRD with high myopia and FTMH combined with retinal re-detachment were diagnosed in three patients. One patient had macula-on RRD with outer LMH. The average follow-up duration was 7.25 ± 1.5 months. The FTMH closed successfully after reoperation, while the outer LMH closed without intervention. Visual acuity insignificantly improved or slightly decreased in all patients. CONCLUSIONS: Patients with high myopia combined with macula-off RRD might be more susceptible to FTMH, causing MH related retinal detachment. Additionally, LMH following SB was noted in patients with macula-on RRD. Therefore, we should raise awareness of MH following SB for RRD repair.


Assuntos
Miopia , Descolamento Retiniano , Perfurações Retinianas , Humanos , Masculino , Feminino , Recurvamento da Esclera/efeitos adversos , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia , Descolamento Retiniano/diagnóstico , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/etiologia , Perfurações Retinianas/cirurgia , Tomografia de Coerência Óptica , Vitrectomia/efeitos adversos , Miopia/cirurgia , Estudos Retrospectivos
18.
BMC Pediatr ; 24(1): 375, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816849

RESUMO

BACKGROUND: Juvenile idiopathic arthritis (JIA), an autoimmune disease affecting children or adolescents and causing joint or systemic symptoms, reportedly has a negative effect on the patients' body height. This study aimed to identify factors attributable to substantially reduced adult height (SRAH) in JIA patients. METHODS: This single-center retrospective cohort study included patients from 2009 to 2019 in Taiwan. We collected JIA patients aged > 18 years at enrollment with a definite diagnosis and undergoing regular outpatient clinic follow-up or disease remission. Target height difference (THD), defined by adult height minus mid-parental height, was calculated for each patient. The calculation results yielded two groups, of which positive THD was defined as the optimal height (OH group) and those with THD below two standardized deviations as the SRAH group. Descriptive statistics and logistic regression analysis were used to analyze the data. RESULTS: Of 92 JIA patients, 57 and 12 were in the OH and the SRAH groups. Earlier disease onset, especially before the six-year-old, was noted in the SRAH group (p = 0.026). The distribution of JIA subtypes differed significantly between the two groups (p < 0.001); enthesis-related arthritis was the commonest subtype in the OH group, and systemic JIA was the commonest in the SRAH group. Half of the patients in the SRAH group had an active disease status at enrollment, which was higher than the OH group (50.0% vs. 21.1%, p = 0.066). More patients in the SRAH group had received orthopedic surgery due to JIA (25% vs. 3.5%, p = 0.034). Multiple logistic regression analysis showed that SRAH was independently related to systemic JIA (OR = 37.6, 95%CI 1.2-1210.5; p = 0.041). CONCLUSION: The subtype of systemic JIA, with its characteristics of early disease onset and active disease status, was the essential factor that significantly impacted adult height.


Assuntos
Artrite Juvenil , Estatura , Humanos , Estudos Retrospectivos , Feminino , Masculino , Adolescente , Criança , Taiwan , Transtornos do Crescimento/etiologia , Fatores de Risco , Adulto , Pré-Escolar
19.
BMC Palliat Care ; 23(1): 24, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273273

RESUMO

OBJECTIVE: This study aims to investigate the experiences of parents who have experienced bereavement in their efforts to preserve memories of their deceased child. METHODS: Employing a qualitative meta-synthesis approach, this study systematically sought relevant qualitative literature by conducting searches across various electronic databases, including PubMed, Embase, CINAHL, PsycINFO, Web of Science, Cochrane Library, and Wiley, up until July 2023. RESULTS: Nine studies are eligible for inclusion and included in the meta-synthesis. Three overarching categories are identified: (1) Affirming the Significance of Memory Making. (2) Best Practices in Memory Making. (3) Barriers to Effective Memory Making. CONCLUSION: Bereaved parents highly value the act of creating lasting memories, emphasizing its profound significance. While forming these memories, it is imperative to offer family-centered care and honor diverse preferences and needs. It is essential to offer effective support to parents, offering them a range of choices. Furthermore, a more comprehensive examination of memory-making practices is required to better understand their influence on parents' recollections of their deceased child.


Assuntos
Luto , Criança , Humanos , Pesar , Pais , Pesquisa Qualitativa
20.
Artigo em Inglês | MEDLINE | ID: mdl-38758243

RESUMO

BACKGROUND: Few studies have examined the preoperative risks and healthcare costs related to free flap revision in hypopharyngeal cancer (HPC) patients. METHODS: A 20-year retrospective case-control study was conducted using the Chang Gung Research Database, focusing on HPC patients who underwent tumor excision and free flap reconstruction from January 1, 2001, to December 31, 2019. The impacts of clinical variables on the need for re-exploration due to free flap complications were assessed using logistic regression. The direct and indirect effects of these complications on medical costs were evaluated by causal mediation analysis. RESULTS: Among 348 patients studied, 43 (12.4%) developed complications requiring re-exploration. Lower preoperative albumin levels significantly increased the risk of complications (OR 2.45, 95% CI 1.12-5.35), especially in older and previously irradiated patients. Causal mediation analysis revealed that these complications explained 11.4% of the effect on increased hospitalization costs, after controlling for confounders. CONCLUSIONS: Lower preoperative albumin levels in HPC patients are associated with a higher risk of microvascular free flap complications and elevated healthcare costs, underscoring the need for enhanced nutritional support before surgery in this population.

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