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1.
Ren Fail ; 46(2): 2359640, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38832483

RESUMO

Research has shown that patients undergoing hemodialysis experience seasonal variations in their serum potassium levels. There was inconsistent seasonal fluctuation in serum potassium levels among the hemodialysis population across different locations. In the form of narrative review for the first time, the article discusses the seasonal changes of serum potassium in this population and its potential reasons, this article demonstrates that it is primarily attributable to seasonal dietary potassium intake. However, existing studies have not quantified seasonal dietary potassium intake, so the results are still speculative. Furthermore, future research ought to further expound upon the clinical implications of seasonal variations in serum potassium levels among dialysis patients, as well as other influencing mechanisms such as the pathophysiological causes of these seasonal changes, particularly those pertaining to dietary, geographical, and regional factors. These findings contribute to a more thorough interpretation of laboratory results in hemodialysis patients and provide important guidance for their individualized dietary management.


Assuntos
Potássio , Diálise Renal , Estações do Ano , Humanos , Potássio/sangue , Falência Renal Crônica/terapia , Falência Renal Crônica/sangue , Potássio na Dieta/administração & dosagem
2.
Bioact Mater ; 37: 348-377, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38694766

RESUMO

Setting time as the fourth dimension, 4D printing allows us to construct dynamic structures that can change their shape, property, or functionality over time under stimuli, leading to a wave of innovations in various fields. Recently, 4D printing of smart biomaterials, biological components, and living cells into dynamic living 3D constructs with 4D effects has led to an exciting field of 4D bioprinting. 4D bioprinting has gained increasing attention and is being applied to create programmed and dynamic cell-laden constructs such as bone, cartilage, and vasculature. This review presents an overview on 4D bioprinting for engineering dynamic tissues and organs, followed by a discussion on the approaches, bioprinting technologies, smart biomaterials and smart design, bioink requirements, and applications. While much progress has been achieved, 4D bioprinting as a complex process is facing challenges that need to be addressed by transdisciplinary strategies to unleash the full potential of this advanced biofabrication technology. Finally, we present future perspectives on the rapidly evolving field of 4D bioprinting, in view of its potential, increasingly important roles in the development of advanced dynamic tissues for basic research, pharmaceutics, and regenerative medicine.

3.
Cell Metab ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38703762

RESUMO

The mitochondrial genome transcribes 13 mRNAs coding for well-known proteins essential for oxidative phosphorylation. We demonstrate here that cytochrome b (CYTB), the only mitochondrial-DNA-encoded transcript among complex III, also encodes an unrecognized 187-amino-acid-long protein, CYTB-187AA, using the standard genetic code of cytosolic ribosomes rather than the mitochondrial genetic code. After validating the existence of this mtDNA-encoded protein arising from cytosolic translation (mPACT) using mass spectrometry and antibodies, we show that CYTB-187AA is mainly localized in the mitochondrial matrix and promotes the pluripotent state in primed-to-naive transition by interacting with solute carrier family 25 member 3 (SLC25A3) to modulate ATP production. We further generated a transgenic knockin mouse model of CYTB-187AA silencing and found that reduction of CYTB-187AA impairs females' fertility by decreasing the number of ovarian follicles. For the first time, we uncovered the novel mPACT pattern of a mitochondrial mRNA and demonstrated the physiological function of this 14th protein encoded by mtDNA.

4.
Insects ; 15(5)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38786859

RESUMO

Insects constitute the largest proportion of animals on Earth and act as significant reservoirs and vectors in disease transmission. Rice thrips (Haplothrips aculeatus, family Phlaeothripidae) are one of the most common pests in agriculture. In this study, the full genome sequence of a novel Ollusvirus, provisionally named "Rice thrips ollusvirus 1" (RTOV1), was elucidated using transcriptome sequencing and the rapid amplification of cDNA ends (RACE). A homology search and phylogenetic tree analysis revealed that the newly identified virus is a member of the family Aliusviridae (order Jingchuvirales). The genome of RTOV1 contains four predicted open reading frames (ORFs), including a polymerase protein (L, 7590 nt), a glycoprotein (G, 4206 nt), a nucleocapsid protein (N, 2415 nt) and a small protein of unknown function (291 nt). All of the ORFs are encoded by the complementary genome, suggesting that the virus is a negative-stranded RNA virus. Phylogenetic analysis using polymerase sequences suggested that RTOV1 was closely related to ollusvirus 1. Deep small RNA sequencing analysis reveals a significant accumulation of small RNAs derived from RTOV1, indicating that the virus replicated in the insect. According to our understanding, this is the first report of an Ollusvirus identified in a member of the insect family Phlaeothripidae. The characterisation and discovery of RTOV1 is a significant contribution to the understanding of Ollusvirus diversity in insects.

5.
Virol J ; 21(1): 117, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802935

RESUMO

BACKGROUND: Equine herpesvirus type 1 (EHV-1) is commonly associated with horse abortion. Currently, there are no reported cases of abortion resulting from EHV-1 infection in donkeys. RESULTS: This was the first survey-based study of Chinese donkeys. The presence of EHV-1 was identified by PCR. This survey was conducted in Chabuchar County, North Xinjiang, China, in 2020. A donkey EHV-1 strain (Chabuchar/2020) was successfully isolated in MDBK cells. Seventy-two of 100 donkey sera were able to neutralize the isolated EHV-1. Moreover, the ORF33 sequence of the donkey-origin EHV-1 Chabuchar/2020 strain showed high levels of similarity in both its nucleotide (99.7‒100%) and amino acid (99.5‒100%) sequences, with those of horse EHV-1 strains. EHV-1 Chabuchar/2020 showed significant consistency and was classified within cluster 1 of horse EHV-1 strains. Further, analysis of the expected ORF30 nucleotide sequence revealed that donkey EHV-1 strains contained guanine at position 2254, resulting in a change to aspartic acid at position 752 of the viral DNA polymerase. Therefore, these strains were classified as horse neuropathogenic strains. Lastly, a phylogenetic tree was constructed using the partial ORF68 nucleotide sequences, showing that the identified donkey EHV-1 strain and the EHV-1 strain found in aborted Yili horses in China comprised a novel independent VIII group. CONCLUSION: This study showed the first isolation and identification of EHV-1 as an etiological agent of abortions in donkeys. Further analysis of the ORF33, ORF30, and ORF68 sequences indicated that the donkey EHV-1 contained the neuropathogenic genotype of strains in the VIII group. It is thus important to be aware of EHV-1 infection in the donkey population, even though the virus has only been identified in donkey abortions in China.


Assuntos
Equidae , Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Pulmão , Filogenia , Animais , Equidae/virologia , Herpesvirus Equídeo 1/isolamento & purificação , Herpesvirus Equídeo 1/genética , Herpesvirus Equídeo 1/classificação , China , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Pulmão/virologia , Feto Abortado/virologia , Feminino , DNA Viral/genética , Fases de Leitura Aberta , Análise de Sequência de DNA , Gravidez , Reação em Cadeia da Polimerase
6.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2648-2653, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38812165

RESUMO

Chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS) is a common urological disease with complex etiology. The treatment effect of western medicine is not satisfactory, and the course of the disease is protracted, which brings great trouble to patients. Traditional Chinese medicine(TCM) has a variety of treatment methods based on syndrome differentiation and treatment, including internal treatment with TCM, acupuncture and massage, and other external treatment methods for comprehensive treatment, with significant effect. This study summarized the etiology and pathogenesis of CP/CPPS and found that western medicine cannot fully explain the etiology and pathogenesis of CP/CPPS. It was believed that CP/CPPS was mainly related to many factors such as special pathogen infection, voiding dysfunction, mental and psychological abnormalities, neuroendocrine abnormalities, immune abnormalities, excessive oxidative stress, pelvic diseases, and heredity. TCM believed that CP/CPPS was caused by damp heat, blood stasis, Qi stagnation, and poisoning and was closely related to the organs of the liver, spleen, kidney, lung, stomach, bladder, and meridians of Chong and Ren channels and three yin channels of the foot. In the treatment of TCM, multiple comprehensive treatment plans are currently used, including internal treatment with TCM(decoction, proprietary Chinese medicine, and unique therapies of famous doctors), acupuncture and massage treatment, and other external treatment methods(rectal administration, topical application of TCM, and ear acupoint pressure). Comprehensive regulation has significant clinical efficacy and prominent characteristics of TCM, and it is worth clinical promotion. This study aims to provide a reference for clinical prevention and treatment of CP/CPPS and points out potential directions for future research in this field.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Dor Pélvica , Prostatite , Humanos , Prostatite/terapia , Prostatite/tratamento farmacológico , Dor Pélvica/terapia , Dor Pélvica/tratamento farmacológico , Masculino , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/administração & dosagem , Doença Crônica , Terapia por Acupuntura
7.
ACS Appl Mater Interfaces ; 16(21): 27831-27840, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757708

RESUMO

Electro-optical synergy has recently been targeted to improve the separation of hot carriers and thereby further improve the efficiency of plasmon-mediated chemical reactions (PMCRs). However, the electro-optical synergy in PMCRs needs to be more deeply understood, and its contribution to bond dissociation and product selectivity needs to be clarified. Herein, the electro-optical synergy in plasmon-mediated reduction of p-bromothiophenol (PBTP) was studied on a plasmonic nanostructured silver electrode using in situ Raman spectroscopy and theoretical calculations. It was found that the electro-optical synergy-induced enhancements in the cleavage of carbon-bromine bonds, reaction rate, and product selectivity (4,4'-biphenyl dithiol vs thiophenol) were largely affected by the applied bias, laser wavelength, and laser power. The theoretical simulation further clarified that the strong electro-optical synergy is attributed to the matching of energy band diagrams of the plasmonic silver with those of the adsorbed PBTP molecules. A deep understanding of the electro-optical synergy in PBTP reduction and the clarification of the mechanism will be highly beneficial for the development of other highly efficient PMCRs.

8.
Nat Commun ; 15(1): 4317, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773086

RESUMO

Transition-metal catalyzed allylic substitution reactions of alkenes are among the most efficient methods for synthesizing diene compounds, driven by the inherent preference for an inner-sphere mechanism. Here, we present a demonstration of an outer-sphere mechanism in Rh-catalyzed allylic substitution reaction of simple alkenes using gem-difluorinated cyclopropanes as allyl surrogates. This unconventional mechanism offers an opportunity for the fluorine recycling of gem-difluorinated cyclopropanes via C - F bond cleavage/reformation, ultimately delivering allylic carbofluorination products. The developed method tolerates a wide range of simple alkenes, providing access to secondary, tertiary fluorides and gem-difluorides with 100% atom economy. DFT calculations reveal that the C - C bond formation goes through an unusual outer-sphere nucleophilic substitution of the alkenes to the allyl-Rh species instead of migration insertion, and the generated carbon cation then forms the C - F bond with tetrafluoroborate as a fluoride shuttle.

9.
Chem Sci ; 15(17): 6552-6561, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38699257

RESUMO

Mucin-related tumor-associated carbohydrate antigens (TACAs) are important and interesting targets for cancer vaccine therapy. However, efficient access to a library of mucin-related TACAs remains a challenging task. One of the key issues is the challenging construction of α-GalNAc linkages. Here, we report highly stereoselective α-glycosylation with GalN3N-phenyl trifluoroacetimidate donors, which features excellent yields, outstanding stereoselectivities, broad substrate scope and mild reaction conditions. This method is successfully applied to highly stereoselective synthesis of GalN3-α-O-Ser, which served as the common intermediate for collective synthesis of a wide range of TACAs including TN antigen, STN antigen, 2,6 STF antigen, 2,3 STF antigen, glycophorin and cores 1-8 mucin-type O-glycans. In particular, the rationale for this highly stereoselective α-glycosylation is provided for the first time using DFT calculations and mechanistic studies, highlighting the crucial roles of reagent combinations (TMSI and Ph3PO) and the H-bonding directing effect of the N3 group.

10.
Nat Mater ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769206

RESUMO

Structurally ordered L10-PtM (M = Fe, Co, Ni and so on) intermetallic nanocrystals, benefiting from the chemically ordered structure and higher stability, are one of the best electrocatalysts used for fuel cells. However, their practical development is greatly plagued by the challenge that the high-temperature (>600 °C) annealing treatment necessary for realizing the ordered structure usually leads to severe particle sintering, morphology change and low ordering degree, which makes it very difficult for the gram-scale preparation of desirable PtM intermetallic nanocrystals with high Pt content for practical fuel cell applications. Here we report a new concept involving the low-melting-point-metal (M' = Sn, Ga, In)-induced bond strength weakening strategy to reduce Ea and promote the ordering process of PtM (M = Ni, Co, Fe, Cu and Zn) alloy catalysts for a higher ordering degree. We demonstrate that the introduction of M' can reduce the ordering temperature to extremely low temperatures (≤450 °C) and thus enable the preparation of high-Pt-content (≥40 wt%) L10-Pt-M-M' intermetallic nanocrystals as well as ten-gram-scale production. X-ray spectroscopy studies, in situ electron microscopy and theoretical calculations reveal the fundamental mechanism of the Sn-facilitated ordering process at low temperatures, which involves weakened bond strength and consequently reduced Ea via Sn doping, the formation and fast diffusion of low-coordinated surface free atoms, and subsequent L10 nucleation. The developed L10-Ga-PtNi/C catalysts display outstanding performance in H2-air fuel cells under both light- and heavy-duty vehicle conditions. Under the latter condition, the 40% L10-Pt50Ni35Ga15/C catalyst delivers a high current density of 1.67 A cm-2 at 0.7 V and retains 80% of the current density after extended 90,000 cycles, which exceeds the United States Department of Energy performance metrics and represents among the best cathodic electrocatalysts for practical proton-exchange membrane fuel cells.

11.
iScience ; 27(4): 109456, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38591005

RESUMO

Spermiogenesis defines the final phase of male germ cell differentiation. While multiple deubiquitinating enzymes have been linked to spermiogenesis, the impacts of deubiquitination on spermiogenesis remain poorly characterized. Here, we investigated the function of UAF1 in mouse spermiogenesis. We selectively deleted Uaf1 in premeiotic germ cells using the Stra8-Cre knock-in mouse strain (Uaf1 sKO), and found that Uaf1 is essential for spermiogenesis and male fertility. Further, UAF1 interacts and colocalizes with USP1 in the testes. Conditional knockout of Uaf1 in testes results in disturbed protein levels and localization of USP1, suggesting that UAF1 regulates spermiogenesis through the function of the deubiquitinating enzyme USP1. Using tandem mass tag-based proteomics, we identified that conditional knockout of Uaf1 in the testes results in reduced levels of proteins that are essential for spermiogenesis. Thus, we conclude that the UAF1/USP1 deubiquitinase complex is essential for normal spermiogenesis by regulating the levels of spermiogenesis-related proteins.

12.
Nat Commun ; 15(1): 3086, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600063

RESUMO

Bioinspired bionic eyes should be self-driving, repairable and conformal to arbitrary geometries. Such eye would enable wide-field detection and efficient visual signal processing without requiring external energy, along with retinal transplantation by replacing dysfunctional photoreceptors with healthy ones for vision restoration. A variety of artificial eyes have been constructed with hemispherical silicon, perovskite and heterostructure photoreceptors, but creating zero-powered retinomorphic system with transplantable conformal features remains elusive. By combining neuromorphic principle with retinal and ionoelastomer engineering, we demonstrate a self-driven hemispherical retinomorphic eye with elastomeric retina made of ionogel heterojunction as photoreceptors. The receptor driven by photothermoelectric effect shows photoperception with broadband light detection (365 to 970 nm), wide field-of-view (180°) and photosynaptic (paired-pulse facilitation index, 153%) behaviors for biosimilar visual learning. The retinal photoreceptors are transplantable and conformal to any complex surface, enabling visual restoration for dynamic optical imaging and motion tracking.


Assuntos
Próteses Visuais , Biônica , Retina , Visão Ocular , Percepção Visual
13.
Magn Reson Imaging ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38579973

RESUMO

BACKGROUND: Dural sinus wall thickness and wall enhancement index (WEI) of dural arteriovenous fistulae (DAVFs) have not been well characterized. This study aimed to measure the sinus wall thickness and WEI by using magnetic resonance vessel wall imaging (MR-VWI). METHODS: A total 27 DAVF patients and 30 normal healthy individuals were enrolled in this study. All participants were scanned by a 3 T MR scanner with the black blood sequence. The wall thickness and the WEI of the great cerebral vein, the intracranial main dural sinuses with DAVFs, and the contralateral sinuses were measured by two independent neuroradiologists. RESULTS: The DAVF-affected sinuses had significantly thicker walls (2.277 ±â€¯0.311 mm vs. 1.446 ±â€¯0.188 mm, P < 0.001) and significantly higher WEI (2.253 ±â€¯0.462 vs. 1.173 ±â€¯0.418, P < 0.001) compared to the contralateral ones. They also had significantly thicker walls (2.277 ±â€¯0.311 mm vs. 1.643 ±â€¯0.173 mm, P < 0.001) and significantly higher WEI (2.253 ±â€¯0.462 vs. 1.124 ±â€¯0.254, P < 0.001) compared to the normal controls. Neither the sinus wall thickness (r = -0.317, P = 0.107) nor the WEI (r = 0.019, P = 0.923) was significantly correlated with the Cognard types in DAVF patients. The WEI of the DAVF draining vein was significantly higher compared to the static venous wall (1.972 ±â€¯0.629 vs. 0.532 ±â€¯0.243, P < 0.001). CONCLUSION: T1-CUBE MRI is useful in measuring sinus all thickness and WEI of DAVFs, providing a new method for diagnosing this disease.

14.
BMC Microbiol ; 24(1): 113, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575881

RESUMO

BACKGROUND: Cryptosporidium is a highly pathogenic parasite responsible for diarrhea in children worldwide. Here, the epidemiological status and genetic characteristics of Cryptosporidium in children with or without diarrhea were investigated with tracking of potential sources in Wenzhou City, China. METHODS: A total of 1032 children were recruited, 684 of whom had diarrhea and 348 without, from Yuying Children's Hospital in Wenzhou, China. Samples of stool were collected from each participant, followed by extraction of DNA, genotyping, and molecular identification of Cryptosporidium species and subtypes. RESULTS: Twenty-two of the 1032 (2.1%) children were infected with Cryptosporidium spp. with 2.5% (17/684) and 1.4% (5/348) in diarrhoeic and asymptomatic children, respectively. Four Cryptosporidium species were identified, including C. parvum (68.2%; 15/22), C. felis (13.6%; 3/22), C. viatorum (9.1%; 2/22), and C. baileyi (9.1%; 2/22). Two C. parvum subtypes named IIdA19G1 (n = 14) and IInA10 (n = 1), and one each of C. felis (XIXa) and C. viatorum (XVaA3g) subtype was found as well. CONCLUSIONS: This is the first research that identified Cryptosporidium in children of Wenzhou, China, using PCR. Identification of zoonotic C. parvum, C. felis, C. viatorum, and their subtypes indicate potential cross-species transmission of Cryptosporidium between children and animals. Additionally, the presence of C. baileyi in children suggests that this species has a wider host range than previously believed and that it possesses the capacity to infect humans.


Assuntos
Criptosporidiose , Cryptosporidium , Criança , Animais , Humanos , Cryptosporidium/genética , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Diarreia/epidemiologia , China/epidemiologia , Fezes/parasitologia , Genótipo , Probabilidade
15.
Sci Adv ; 10(17): eadk3852, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38657063

RESUMO

Many insect pests, including the brown planthopper (BPH), undergo windborne migration that is challenging to observe and track. It remains controversial about their migration patterns and largely unknown regarding the underlying genetic basis. By analyzing 360 whole genomes from around the globe, we clarify the genetic sources of worldwide BPHs and illuminate a landscape of BPH migration showing that East Asian populations perform closed-circuit journeys between Indochina and the Far East, while populations of Malay Archipelago and South Asia undergo one-way migration to Indochina. We further find round-trip migration accelerates population differentiation, with highly diverged regions enriching in a gene desert chromosome that is simultaneously the speciation hotspot between BPH and related species. This study not only shows the power of applying genomic approaches to demystify the migration in windborne migrants but also enhances our understanding of how seasonal movements affect speciation and evolution in insects.


Assuntos
Migração Animal , Genômica , Vento , Animais , Genômica/métodos , Hemípteros/genética , Genoma de Inseto , Genética Populacional
16.
Chemistry ; : e202400629, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594211

RESUMO

Herein, we synthesized two donor-acceptor (D-A) type small organic molecules with self-assembly properties, namely MPA-BT-BA and MPA-2FBT-BA, both containing a low acidity anchoring group, benzoic acid. After systematically investigation, it is found that, with the fluorination, the MPA-2FBT-BA demonstrates a lower highest occupied molecular orbital (HOMO) energy level, higher hole mobility, higher hydrophobicity and stronger interaction with the perovskite layer than that of MPA-BT-BA. As a result, the device based-on MPA-2FBT-BA displays a better crystallization and morphology of perovskite layer with larger grain size and less non-radiative recombination. Consequently, the device using MPA-2FBT-BA as hole transport material achieved the power conversion efficiency (PCE) of 20.32 % and remarkable stability. After being kept in an N2 glove box for 116 days, the unsealed PSCs' device retained 93 % of its initial PCE. Even exposed to air with a relative humidity range of 30±5 % for 43 days, its PCE remained above 91 % of its initial condition. This study highlights the vital importance of the fluorination strategy combined with a low acidity anchoring group in SAMs, offering a pathway to achieve efficient and stable PSCs.

17.
Angew Chem Int Ed Engl ; : e202400751, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634352

RESUMO

Developing efficient and anti-corrosive oxygen reduction reaction (ORR) catalysts is of great importance for the applications of proton exchange membrane fuel cells (PEMFCs). Herein, we report a novel approach to prepare metal oxides supported intermetallic Pt alloy nanoparticles (NPs) via the reactive metal-support interaction (RMSI) as ORR catalysts, using Ni-doped cubic ZrO2 (Ni/ZrO2) supported L10-PtNi NPs as a proof of concept. Benefiting from the Ni migration during RMSI, the oxygen vacancy concentrations in the support are increased, leading to an electron enrichment of Pt. The optimal L10-PtNi-Ni/ZrO2-RMSI catalyst achieves remarkably low mass activity (MA) loss (17.8 %) after 400,000 accelerated durability test cycles in a half-cell and exceptional PEMFC performance (MA=0.76 A mgPt -1 at 0.9 V, peak power density=1.52/0.92 W cm-2 in H2-O2/-air, and 18.4 % MA decay after 30,000 cycles), representing the best reported Pt-based ORR catalysts without carbon supports. Density functional theory (DFT) calculations reveal that L10-PtNi-Ni/ZrO2-RMSI requires a lower energetic barrier for ORR than L10-PtNi-Ni/ZrO2 (direct loading), which is ascribed to a decreased Bader charge transfer between Pt and *OH, and the improved stability of L10-PtNi-Ni/ZrO2-RMSI compared to L10-PtNi-C can be contributed to the increased adhesion energy and Ni vacancy formation energy within the PtNi alloy.

18.
Chemosphere ; 358: 142175, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679173

RESUMO

Carbamazepine (CBZ) is a widely used anticonvulsant drug that has been detected in aquatic environments. This study investigated the toxicity of its by-products (CBZ-BPs), which may surpass CBZ. Unlike the previous studies, this study offered a more systematic approach to identifying toxic BPs and inferring degradation pathways. Furthermore, quadrupole time-of-flight (QTOF) and density functional theory (DFT) calculations were employed to analyze CBZ-BP structures and degradation pathways. Evaluation of total organic carbon (TOC) and total nitrogen (TN) mineralization rates, revealed carbon (C) greater susceptibility to mineralization compared with nitrogen (N). Furthermore, three rules were established for CBZ decarbonization and N removal during degradation, observing the transformation of aromatic compounds into aliphatic hydrocarbons and stable N-containing organic matter over time. Five potentially highly toxic BPs were screened from 14 identified BPs, with toxicity predictions guiding the selection of commercial standards for quantification and true toxicity testing. Additionally, BP207 emerged as the most toxic, supported by the predictive toxicity accumulation model (PTAM). Notably, highly toxic BPs feature an acridine structure, indicating its significant contribution to toxicity. These findings offered valuable insights into the degradation mechanisms of emerging contaminants and the biosafety of aquatic environments during deep oxidation.


Assuntos
Carbamazepina , Peróxido de Hidrogênio , Poluentes Químicos da Água , Carbamazepina/toxicidade , Carbamazepina/química , Poluentes Químicos da Água/toxicidade , Peróxido de Hidrogênio/química , Raios Ultravioleta , Nitrogênio , Anticonvulsivantes/toxicidade , Anticonvulsivantes/química
19.
Angew Chem Int Ed Engl ; : e202405838, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647574

RESUMO

Transition-metal-catalyzed [4+4] cycloaddition leading to cyclooctanoids has centered on dimerization between 1,3-diene-type substrates. Herein, we describe a [4σ+4π-1] and [4σ+4π] cycloaddition strategy to access 7/8-membered fused carbocycles through rhodium-catalyzed coupling between the 4σ-donor (benzocyclobutenones) and pendant diene (4π) motifs. The two pathways can be controlled by adjusting the solvated CO concentration. A broad range (>40 examples) of 5-6-7 and 5-6-8 polyfused carbocycles was obtained in good yields (up to 90 %). DFT calculations, kinetic monitoring and 13C-labeling experiments were carried out, suggesting a plausible mechanism. Notably, one 5-6-7 tricycle was found to be a very rare, potent, and selective ligand for the liver X receptor ß (KD=0.64 µM), which is a potential therapeutic target for cholesterol-metabolism-related fatal diseases.

20.
Insects ; 15(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38535345

RESUMO

Many hosts utilize the ubiquitin system to defend against viral infection. As a key subunit of the ubiquitin system, the role of polyubiquitin in the viral infection of insects is unclear. Here, we identified the full-length cDNA of the polyubiquitin-C (UBC) gene in Laodelphax striatellus, the small brown planthopper (SBPH). LsUBC was expressed in various tissues and was highly expressed in salivary glands, midgut, and reproductive systems. Furthermore, the LsUBC expression profiles in the developmental stages showed that LsUBC was ubiquitously expressed in seven developmental stages and was highest expressed in female adults with SBPH. qRT-PCR analyses indicated that rice stripe virus (RSV) infection promoted the LsUBC expression. Knockdown of LsUBC mRNA via RNA interference increased RSV accumulation. These findings suggest that LsUBC inhibits RSV accumulation in L. striatellus.

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