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1.
Diagnostics (Basel) ; 14(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38928638

RESUMO

Carotid blowout syndrome (CBS) is a rare yet life-threatening complication that occurs after radiation therapy (RT). This study aimed to determine the incidence of CBS in patients with head and neck cancer (HNC) undergoing contemporary RT and to explore potential discrepancies in the risk of CBS between nasopharyngeal cancer (NPC) and non-NPC patients. A total of 1084 patients with HNC who underwent RT between 2013 and 2023 were included in the study. All patients were under regular follow-ups at the radio-oncology department, and underwent annual contrast-enhanced computed tomography and/or magnetic resonance imaging for cancer recurrence surveillance. Experienced neuroradiologists and vascular neurologists reviewed the recruited patients' images. Patients were further referred to the neurology department for radiation vasculopathy evaluation. The primary outcome of this study was CBS. Patients were categorized into NPC and non-NPC groups and survival analysis was employed to compare the CBS risk between the two groups. A review of the literature on CBS incidence was also conducted. Among the enrolled patients, the incidence of CBS in the HNC, NPC, and non-NPC groups was 0.8%, 0.9%, and 0.7%, respectively. Kaplan-Meier analysis revealed no significant difference between the NPC and non-NPC groups (p = 0.34). Combining the findings for our cohort with those of previous studies revealed that the cumulative incidence of CBS in patients with HNC is 5% (95% CI = 3-7%) after both surgery and RT, 4% (95% CI = 2-6%) after surgery alone, and 5% (95% CI = 3-7%) after RT alone. Our findings indicate a low incidence of CBS in patients with HNC undergoing contemporary RT. Patients with NPC may have a CBS risk close to that of non-NPC patients. However, the low incidence of CBS could be a potentially cause of selection bias and underestimation bias.

2.
Opt Express ; 32(8): 13562-13573, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859323

RESUMO

We propose a method for simulating a 1D non-Hermitian Su-Schrieffer-Heeger model with modulated nonreciprocal hopping using a cyclic three-mode optical system. The current system exhibits different localization of topologically nontrivial phases, which can be characterized by the winding number. We find that the eigenenergies of such a system undergo a real-complex transition as the nonreciprocal hopping changes, accompanied by a non-Bloch parity-time symmetry breaking. We explain this phase transition by considering the evolution of saddle points on the complex energy plan and the ratio of complex eigenenergies. Additionally, we demonstrate that the skin states resulting from the non-Hermitian skin effect possess higher-order exceptional points under the critical point of the non-Bloch parity-time phase transition. Furthermore, we investigate the non-Hermitian skin phase transition by the directional mean inverse participation ratio and the generalized Brillouin zone. This work provides an alternative way to investigate the novel topological and non-Hermitian effects in nonreciprocal optical systems.

3.
Front Plant Sci ; 15: 1378418, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38872893

RESUMO

Introduction: The strong aromatic characteristics of the tender leaves of Toona sinensis determine their quality and economic value. Methods and results: Here, GC-MS analysis revealed that caryophyllene is a key volatile compound in the tender leaves of two different T. sinensis varieties, however, the transcriptional mechanisms controlling its gene expression are unknown. Comparative transcriptome analysis revealed significant enrichment of terpenoid synthesis pathway genes, suggesting that the regulation of terpenoid synthesis-related gene expression is an important factor leading to differences in aroma between the two varieties. Further analysis of expression levels and genetic evolution revealed that TsTPS18 is a caryophyllene synthase, which was confirmed by transient overexpression in T. sinensis and Nicotiana benthamiana leaves. Furthermore, we screened an AP2/ERF transcriptional factor ERF-IX member, TsERF66, for the potential regulation of caryophyllene synthesis. The TsERF66 had a similar expression trend to that of TsTPS18 and was highly expressed in high-aroma varieties and tender leaves. Exogenous spraying of MeJA also induced the expression of TsERF66 and TsTPS18 and promoted the biosynthesis of caryophyllene. Transient overexpression of TsERF66 in T. sinensis significantly promoted TsTPS18 expression and caryophyllene biosynthesis. Discussion: Our results showed that TsERF66 promoted the expression of TsTPS18 and the biosynthesis of caryophyllene in T. sinensis leaves, providing a strategy for improving the aroma of tender leaves.

4.
Brain ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875478

RESUMO

USP25 encodes ubiquitin-specific proteases 25, a key member of deubiquitinating enzyme family and is involved in neural fate determination. Although abnormal expression in Down's syndrome was reported previously, the specific role of USP25 in human diseases has not been defined. In this study, we performed trio-based whole exome sequencing in a cohort of 319 cases (families) with generalized epilepsy of unknown etiology. Five heterozygous USP25 variants including two de novo and three co-segregated variants were determined in eight individuals affected by generalized seizures and/or febrile seizures from five unrelated families. The frequency of USP25 variants showed a significantly high aggregation in this cohort compared to the East Asian population and all populations in the gnomAD database. The mean onset ages of febrile and afebrile seizures were 10 months (infancy) and 11.8 years (juvenile), respectively. The patients achieved seizure freedom except one had occasional nocturnal seizures at the last follow-up. Two patients exhibited intellectual disability. Usp25 was ubiquitously expressed in mouse brain with two peaks on embryonic days (E14‒E16) and postnatal day 21, respectively. Similarly, USP25 expressed in fetus/early childhood stage with a second peak at approximately 12‒20 years old in human brain, consistent with the seizure onset age at infancy and juvenile in the patients. To investigate the functional impact of USP25 deficiency in vivo, we established Usp25 knock-out mice, which showed increased seizure susceptibility compared to wild-type mice in pentylenetetrazol-induced seizure test. To explore the impact of USP25 variants, we employed multiple functional detections. In HEK293T cells, the severe phenotype associated variant (p.Gln889Ter) led to a significant reduction of mRNA and protein expressions but formed a stable truncated dimers with increment of deubiquitinating enzyme activities and abnormal cellular aggregations, indicating a gain-of-function effect. The p.Gln889Ter and p.Leu1045del increased neuronal excitability in mice brain, with a higher firing ability in p.Gln889Ter. These functional impairments align with the severity of the observed phenotypes, suggesting a genotype-phenotype correlation. Hence, a moderate association between USP25 and epilepsy was noted, indicating USP25 is potentially a predisposing gene for epilepsy. Our results from Usp25 null mice and the patient-derived variants indicated that USP25 would play epileptogenic role via loss-of-function or gain-of-function effects. The truncated variant p.Gln889Ter would have profoundly different effect on epilepsy. Together, our results underscore the significance of USP25 heterozygous variants in epilepsy, thereby highlighting the critical role of USP25 in the brain.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38880209

RESUMO

BACKGROUND: Despite the large patient base in Asia, the prognostic factors of patients with non-eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP) remain largely undetermined. OBJECTIVE: We aimed to systematically investigate the predictive value of clinical and biological variables for non-eosinophilic CRSwNP. METHODS: Fifty-one patients with non-eosinophilic CRSwNP who underwent functional endoscopic surgery were recruited. Clinical information and assessment were comprehensively collected before and after surgery. A broad spectrum of biomarkers was measured in tissue homogenates using multiple assays. A random forest algorithm and stepwise logistic regression were used to construct clinical, biological, and combined models. RESULTS: A total of 41.2% of non-eosinophilic CRSwNP patients were uncontrolled more than 6 months after surgery. We identified one clinical variable (22-item Sino-Nasal Outcome Test score) and four biomarkers (programmed cell death ligand 1, platelet-derived growth factor subunit B [PDGF-ß], macrophage inflammatory protein-3b, and PDGF-α) that were significantly predictive of the surgical outcome. The clinical, biological, and combined models showed predictive ability with areas under the curve of 0.78, 0.83, and 0.89, respectively. PDGF-ß and programmed cell death ligand 1 were identified as independent biomarkers for the prognosis of patients with CRSwNP without considerable eosinophilic infiltration. CONCLUSION: This study shows that clinical and biological factors, such as the 22-item Sino-Nasal Outcome Test score and PDGF-ß, are predictive of the post-functional endoscopic surgical prognosis of non-eosinophilic CRSwNP patients.

6.
Photodermatol Photoimmunol Photomed ; 40(4): e12986, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38874329

RESUMO

BACKGROUND/PURPOSE: Phototherapy has emerged as a safe yet effective form of treatment of atopic dermatitis (AD). Few studies have been done to evaluate the efficacy of phototherapy in Asian children. The aim of this study was to review the phototherapy experience in a cohort of Asian pediatric patients with AD at a tertiary dermatologic center in Singapore. METHODS: A retrospective study of patients 18 years and below with AD who had undergone phototherapy at KK Women's and Children's Hospital, Singapore, over a 4-year period was performed. RESULTS: Sixty-two patients were identified, between ages 4 and 16 years (mean age 11 years) at the time of commencement of phototherapy. Thirty-five (60%) patients were males and 23 (40%) were females. Most patients had moderate to severe disease, with 60.3% of the patients with an initial body surface area (BSA) involvement of 31%-60% and 13.8% of the patients with an initial BSA involvement of 61%-90%. For patients who had undergone narrowband ultraviolet B (NBUVB) and combined ultraviolet A (UVA) and NBUVB phototherapy, the mean reduction of the Eczema Area and Severity Index (EASI) scores were 11.4 and 7.9, respectively. Common side effects experienced include xerosis, pruritus, erythema, and pain. Other reasons for cessation of therapy in the NBUVB group included time commitment difficulty (9.3%), hyperactivity (2.3%), and claustrophobia (2.3%). Two patients that had photochemotherapy (psoralen + UVA) [PUVA] suffered from post-UVA burns requiring cessation of treatment. More than half of the patients (56.9%) treated with phototherapy experienced treatment success with improvement in Investigator Global Assessment and EASI scores. 86.2% of the patients had good compliance to the treatment regime, 12% had poor-compliance, and 3.4% were lost to follow-up. CONCLUSION: Phototherapy is a useful treatment adjunct for moderate to severe AD in Asian children.


Assuntos
Dermatite Atópica , Humanos , Dermatite Atópica/terapia , Dermatite Atópica/radioterapia , Criança , Feminino , Adolescente , Masculino , Singapura , Pré-Escolar , Estudos Retrospectivos , Fototerapia , Terapia Ultravioleta/efeitos adversos
7.
Soft Matter ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38894602

RESUMO

The surface of polytetrafluoroethylene (PTFE) bulk materials was modified by irradiation at high temperatures using a 1.2 MeV electron beam. The mass wear rate was decreased from 2.5 × 10-6 g N-1 m-1 to 0.08 × 10-6 g N-1 m-1, and the hardness was increased from 33.2 MPa to 93.9 MPa. The yield strength was increased from 12.1 MPa to 25.8 MPa and Young's modulus was enhanced from 101 MPa to 261 MPa. The use of electron beam irradiation on PTFE at high temperature is an effective modification method to significantly improve its wear resistance and hardness, and increase the elastic response range of PTFE. The chemical reaction induced by electron irradiation at high temperature changes the molecular structure of the PTFE bulk material from highly linear to a network, thus improving the surface mechanical properties of PTFE.

8.
Chem Commun (Camb) ; 60(51): 6532-6535, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38837153

RESUMO

Polysubstituted acrylamides are ubiquitous in bioactive molecules and natural products. However, synthetic methods for the assembly of these important motifs remain underdeveloped. Herein, we report the expedient synthesis of structurally diverse and synthetically challenging polysubstituted acrylamides from readily available aromatic amines, cyclopropenones (CpOs), and aryl halides via the synergistic merging of nucleophilic phosphine-mediated amidation and palladium-catalyzed C-H arylation. The reaction is scalable, and some obtained acrylamides proved to be solid state luminogens with obvious aggregation-induced emission (AIE) properties, demonstrating the synthetic potential in drug discovery and material development.

9.
Dig Liver Dis ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38851975

RESUMO

BACKGROUD: The use of neuromodulators is prevalent in various functional gastrointestinal disease. However, data concerning the outcomes of these treatments in functional esophageal disorders (FED) remains limited and inadequate. AIMS: The aim of the present study is to examine the efficacy of central neuromodulators in FED. METHODS: We searched PubMed, EMBASE, and the Cochrane library databases from inception to April 2023. Randomized controlled trials that compared the effects of neuromodulators and placebos on FED are included. Primary outcome is the symptom improvement, and Rome IV criteria is used to assess eligible studies. RESULTS: Eleven randomized controlled studies (three for functional chest pain, four for reflux hypersensitivity/functional heartburn, three for globus, and one for functional dysphagia) were included in the final analysis. Neuromodulators reduced chest pain by 52%-71% in patients with functional chest pain, and alleviated symptom by 46%-75% in patients with globus (n = 3, Odds ratio 6.30, 95% confidence interval 4.17-9.50). However, the results were inconsistent for reflux hypersensitivity and functional heartburn. There was a lack of convincing evidence to support the use of neuromodulators for functional dysphagia. The use of neuromodulators did not have a significant impact on the quality of life. CONCLUSIONS: Functional chest pain and globus may potentially benefit from the use of neuromodulators, but their effectiveness for functional dysphagia, functional heartburn and reflux hypersensitivity remains controversial. More controlled trials are needed to confirm the therapeutic effects on these conditions.

10.
ACS Appl Mater Interfaces ; 16(23): 30176-30184, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38826007

RESUMO

Single-component white-light luminescent materials are considered an economical and facile choice for phosphor-converted white light-emitting diodes (pc-WLEDs). Here, a new single-component white-light-emitting material Cs2MnCl4:Eu2+ based on the combination of a lead-free halide structure and a rare-earth ion is first reported. Benefiting from the smart dilution-sensitization design strategy, white light composed of dual broad emission originating from Eu2+ (blue light, 444 nm, 4f65d1 → 4f7) and Mn2+ (yellow light, 566 nm, 4T1g → 6A1g) was successfully realized under near-ultraviolet light (404 nm) radiation with a high photoluminescence quantum yield of 66%. Based on the single-source Cs2MnCl4:Eu2+ phosphor, a pc-WLEDs device with "eye-friendly" white light production was successfully fabricated. The pc-WLEDs exhibit suitable color coordinates of (0.3294, 0.2746) and a high color rendering index of 82.3, demonstrating the potential in the future health-conscious illumination application by reducing the risk of eye strain and high-energy blue-light damage. This work achieves a new single-component white-light-emitting Mn-based halide phosphor and provides a new path for the design of single-component white light sources in Mn-based halides.

11.
Front Cell Dev Biol ; 12: 1407428, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887516

RESUMO

The mortality of hepatocellular carcinoma (HCC) is on the rise globally, particularly in the Western world, with etiology gradually shifting from virus-related liver diseases to metabolic disorders such as non-alcoholic fatty liver disease. Early detection of HCC is challenging, and effective prognostic indicators are currently lacking, urgently necessitating reliable markers to assist in treatment planning and clinical management. Here, we introduce hepatocellular carcinoma senescence genes (HSG) to assess cellular senescence in HCC and devise a hepatocellular carcinoma senescence score (HSS) for prognostic prediction. Higher HSS levels signify poorer prognosis and increased tumor proliferation activity. Additionally, we observe alterations in the tumor immune microenvironment with higher HSS levels, such as increased infiltration of Treg, potentially providing a basis for immunotherapy. Furthermore, we identify key genes, such as PTTG1, within the senescence gene set and demonstrate their regulatory roles in HCC cells and Treg through experimentation. In summary, we establish a scoring system based on hepatocellular carcinoma senescence genes for prognostic prediction in HCC, potentially offering guidance for clinical treatment planning.

12.
Anal Chem ; 96(25): 10111-10115, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38869290

RESUMO

The Si window is the most widely used internal reflection element (IRE) for electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), yet local chemical etching on Si by concentrated OH- anions bottlenecks the reliable application of this method in strong alkaline electrolytes. In this report, atomic layer deposition of a 25 nm nonconductive TiO2 barrier layer on the reflecting plane of a Si prism is demonstrated to address this challenge. In situ ATR-SEIRAS measurement on a Au film electrode with the Si/TiO2 composite IRE in 1 M NaOH reveals reversible global spectral features without spectral distortion at 1000-1300 cm-1, in stark contrast to those obtained with a bare Si window. By applying this structured ATR-SEIRAS, ethanol electrooxidation on a Pt/C catalyst in 1 and 5 M NaOH is explored, manifesting that such high pH values prevent the adsorption of as-formed acetate in the C2 pathway but not that of CO intermediate in the C1 pathway.

13.
J Nanobiotechnology ; 22(1): 358, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907270

RESUMO

BACKGROUND: Hypoxia-activated prodrug (HAP) is a promising candidate for highly tumor-specific chemotherapy. However, the oxygenation heterogeneity and dense extracellular matrix (ECM) of tumor, as well as the potential resistance to chemotherapy, have severely impeded the resulting overall efficacy of HAP. RESULTS: A HAP potentiating strategy is proposed based on ultrasound responsive nanodroplets (PTP@PLGA), which is composed of protoporphyrin (PpIX), perfluoropropane (PFP) and a typical HAP, tirapazamine (TPZ). The intense vaporization of PFP upon ultrasound irradiation can magnify the sonomechanical effect, which loosens the ECM to promote the penetration of TPZ into the deep hypoxic region. Meanwhile, the PpIX enabled sonodynamic effect can further reduce the oxygen level, thus activating the TPZ in the relatively normoxic region as well. Surprisingly, abovementioned ultrasound effect also results in the downregulation of the stemness of cancer cells, which is highly associated with drug-refractoriness. CONCLUSIONS: This work manifests an ideal example of ultrasound-based nanotechnology for potentiating HAP and also reveals the potential acoustic effect of intervening cancer stem-like cells.


Assuntos
Fluorocarbonos , Nanopartículas , Pró-Fármacos , Protoporfirinas , Tirapazamina , Humanos , Tirapazamina/farmacologia , Tirapazamina/química , Protoporfirinas/farmacologia , Protoporfirinas/química , Fluorocarbonos/química , Fluorocarbonos/farmacologia , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Linhagem Celular Tumoral , Nanopartículas/química , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Ondas Ultrassônicas , Animais , Matriz Extracelular/metabolismo , Camundongos , Neoplasias/tratamento farmacológico
14.
Artigo em Inglês | MEDLINE | ID: mdl-38909634

RESUMO

BACKGROUND: The Spike protein mutation of SARS-CoV-2 led to decreased protective effect of various vaccines and monoclonal antibodies, suggesting that blocking SARS-CoV-2 infection by targeting host factors would make the therapy more resilient against virus mutations. Angiotensin converting enzyme 2 (ACE2) is the host receptor of SARS-CoV-2 and its variants, as well as many other coronaviruses. Down-regulation of ACE2 expression in the respiratory tract may prevent viral infection. Antisense oligonucleotides (ASOs) can be rationally designed based on sequence data, require no delivery system, and can be administered locally. OBJECTIVE: We sought to design ASOs that can block SARS-CoV-2 by down-regulating ACE2 in human airway. METHODS: ACE2-targeting ASOs were designed using a bioinformatic method and screened in cell lines. Human primary nasal epithelial cells cultured at the air-liquid interface and humanized ACE2 mice were used to detect the ACE2 reduction levels and the safety of ASOs. ASOs pretreated nasal epithelial cells and mice were infected and then used to detect the viral infection levels. RESULTS: ASOs reduced ACE2 expression on mRNA and protein level in cell lines and in human nasal epithelial cells. Furthermore they efficiently suppressed virus replication of three different SARS-CoV-2 variants in human nasal epithelial cells. In vivo, ASOs also down-regulated human ACE2 in humanized ACE2 mice and thereby reduced viral load, histopathological changes in lungs, and they increased survival of mice. CONCLUSION: ACE2-targeting ASOs can effectively block SARS-COV-2 infection. Our study provides a new approach for blocking SARS-CoV-2 and other ACE2-targeting virus in high-risk populations.

15.
Front Cell Infect Microbiol ; 14: 1380312, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836055

RESUMO

Legionella, one of the main pathogens that causes community-acquired pneumonia, can lead to Legionella pneumonia, a condition characterized predominantly by severe pneumonia. This disease, caused by the bacterium Legionella pneumophila, can quickly progress to critical pneumonia and is often associated with damage to multiple organs. As a result, it requires close attention in terms of clinical diagnosis and treatment. Omadacycline, a new type of tetracycline derivative belonging to the aminomethylcycline class of antibiotics, is a semi-synthetic compound derived from minocycline. Its key structural feature, the aminomethyl modification, allows omadacycline to overcome bacterial resistance and broadens its range of effectiveness against bacteria. Clinical studies have demonstrated that omadacycline is not metabolized in the body, and patients with hepatic and renal dysfunction do not need to adjust their dosage. This paper reports a case of successful treatment of Legionella pneumonia with omadacycline in a patient who initially did not respond to empirical treatment with moxifloxacin. The patient also experienced electrolyte disturbance, as well as dysfunction in the liver and kidneys, delirium, and other related psychiatric symptoms.


Assuntos
Antibacterianos , Legionella pneumophila , Doença dos Legionários , Tetraciclinas , Humanos , Tetraciclinas/uso terapêutico , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Doença dos Legionários/tratamento farmacológico , Doença dos Legionários/microbiologia , Legionella pneumophila/efeitos dos fármacos , Resultado do Tratamento , Masculino , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Moxifloxacina/uso terapêutico , Pessoa de Meia-Idade
16.
Antioxidants (Basel) ; 13(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38929132

RESUMO

Cell death involving oxidative stress and mitochondrial dysfunction is a major cause of dopaminergic neuronal loss in the substantia nigra (SN) of Parkinson's disease patients. Ergothioneine (ET), a natural dietary compound, has been shown to have cytoprotective functions, but neuroprotective actions against PD have not been well established. 6-Hydroxydopamine (6-OHDA) is a widely used neurotoxin to simulate the degeneration of dopaminergic (DA) neurons in Parkinson's disease. In this study, we investigated the protective effect of ET on 6-OHDA treated iPSC-derived dopaminergic neurons (iDAs) and further confirmed the protective effects in 6-OHDA-treated human neuroblastoma SH-SY5Y cells. In 6-OHDA-treated cells, decreased mitochondrial membrane potential (ΔΨm), increased mitochondrial reactive oxygen species (mROS), reduced cellular ATP levels, and increased total protein carbonylation levels were observed. 6-OHDA treatment also significantly decreased tyrosine hydroxylase levels. These effects were significantly decreased when ET was present. Verapamil hydrochloride (VHCL), a non-specific inhibitor of the ET transporter OCTN1 abrogated ET's cytoprotective effects, indicative of an intracellular action. These results suggest that ET could be a potential therapeutic for Parkinson's disease.

17.
Neurochem Res ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38909329

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is a therapeutic strategy that shows promise in ameliorating the clinical sequelae following traumatic brain injury (TBI). These improvements are associated with neuroplastic changes in neurons and their synaptic connections. However, it has been hypothesized that rTMS may also modulate microglia and astrocytes, potentially potentiating their neuroprotective capabilities. This study aims to investigate the effects of high-frequency rTMS on microglia and astrocytes that may contribute to its neuroprotective effects. Feeney's weight-dropping method was used to establish rat models of moderate TBI. To evaluate the neuroprotective effect of high frequency rTMS on rats by observing the synaptic ultrastructure and the level of neuron apoptosis. The levels of several important inflammation-related proteins within microglia and astrocytes were assessed through immunofluorescence staining and western blot. Our findings demonstrate that injured neurons can be rescued through the modulation of microglia and astrocytes by rTMS. This modulation plays a key role in preserving the synaptic ultrastructure and inhibiting neuronal apoptosis. Among microglia, we observed that rTMS inhibited the levels of proinflammatory factors (CD16, IL-6 and TNF-α) and promoted the levels of anti-inflammatory factors (CD206, IL-10 and TNF-ß). rTMS also reduced the levels of pyroptosis within microglia and pyroptosis-related proteins (NLRP3, Caspase-1, GSDMD, IL-1ß and IL-18). Moreover, rTMS downregulated P75NTR expression and up-regulated IL33 expression in astrocytes. These findings suggest that regulation of microglia and astrocytes is the mechanism through which rTMS attenuates neuronal inflammatory damage after moderate TBI.

18.
Sci Rep ; 14(1): 14159, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898168

RESUMO

Based on the disaster-pregnant environment and development characteristics of landslide disasters in the western region of Henan Province, a generalized model was established by taking the "oblique-cut" locking rock slope in the layered rock slope as the research object. The numerical simulation method was used to analyze the deformation and failure mechanism and stability influence law of the oblique-cut locking rock slope in western Henan under rainfall conditions. The results show that the inclination angle of the weak interlayer directly affects the deformation and failure characteristics of the slope rock mass. With the increase of the geometric parameters of the slope and the inclination angle of the weak interlayer, the failure mechanism is manifested as the slip shear failure along the level at the foot of the slope → the slip shear failure along the level at the foot of the slope (the sliding surface moves upward) → the shear failure in the middle of the slope surface → the slip shear failure along the level at the foot of the slope (the sliding surface moves downward) → the uplift shear failure at the lower edge of the rock layer. When the dip angle of the weak interlayer is constant, the slope stability decreases gradually with the increase in slope gradient and slope height, and the geometric factors of the slope control the overall change trend of the slope stability coefficient. When the slope is greater than 55° and the slope height is greater than 55 m, the shear stress of the slope locking section exceeds its shear strength, and the probability of landslide instability is greatly increased.

19.
Nature ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898275

RESUMO

Naturally occurring (native) sugars and carbohydrates contain numerous hydroxyl groups of similar reactivity1,2. Chemists, therefore, rely typically on laborious, multi-step protecting-group strategies3 to convert these renewable feedstocks into reagents (glycosyl donors) to make glycans. The direct transformation of native sugars to complex saccharides remains a notable challenge. Here we describe a photoinduced approach to achieve site- and stereoselective chemical glycosylation from widely available native sugar building blocks, which through homolytic (one-electron) chemistry bypasses unnecessary hydroxyl group masking and manipulation. This process is reminiscent of nature in its regiocontrolled generation of a transient glycosyl donor, followed by radical-based cross-coupling with electrophiles on activation with light. Through selective anomeric functionalization of mono- and oligosaccharides, this protecting-group-free 'cap and glycosylate' approach offers straightforward access to a wide array of metabolically robust glycosyl compounds. Owing to its biocompatibility, the method was extended to the direct post-translational glycosylation of proteins.

20.
Huan Jing Ke Xue ; 45(6): 3363-3374, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897758

RESUMO

The ecological environment of the middle Yellow River is highly vulnerable. Conducting a scientific assessment of landscape pattern vulnerability holds great significance, as it serves as the basis for the rational construction of the ecological environment in this area. Based on five periods of land use data from the middle Yellow River from 1990 to 2018, the landscape pattern vulnerability index was employed to analyze the spatio-temporal evolution of the landscape pattern vulnerability. Furthermore, the influencing factors for landscape pattern vulnerability in different natural geomorphological divisions were explored using an optimal parameters-based geographical detector model. The results showed that:① From 1990 to 2018, cultivated land (which accounted for 36.96 % to 39.97 % of the area) remained the predominant landscape in the middle Yellow River. Among all landscape types, cultivated land and construction land exhibited the most significant changes. The area of cultivated land decreased by 10 185.00 km2, whereas the area of construction land increased by 7 678.46 km2. ② From 1990 to 2018, the landscape pattern was dominated by low and medium vulnerability and accounted for 70 %-80 % of the total area. The high and higher vulnerability areas were concentrated in the loess hilly and gully region, whereas the lower vulnerability area was concentrated in the valley plain and the earth-rock mountain regions. During this period, landscape pattern vulnerability underwent an incipient decrease, followed by a subsequent increase. From 1990 to 2000 and from 2000 to 2005, the changes in the level of landscape pattern vulnerability were dominated by a "reduction in the degree of vulnerability". However, from 2005 to 2010 and from 2010 to 2018, it was mainly an "increase in the degree of vulnerability". ③ Annual precipitation and NDVI were the main factors influencing the vulnerability of landscape patterns, whereas the influencing factors varied across different natural geomorphological divisions:the loess hilly and gully region and the earth-rock mountain region were dominated by natural factors, with annual precipitation and DEM being the dominant factors, respectively; the loess plateau tableland-gully region, valley plain region, and sandy land and desert region were dominated by human factors, with population density, degree of land use, and distance from roads being the dominant factors, respectively. The interaction results of any two influencing factors were manifested as two-factor enhancement or nonlinear enhancement. Risk detection revealed that high vulnerability areas of landscape patterns in different natural geomorphological divisions were distributed over distinct ranges of their corresponding dominant factors. Therefore, in the practices of ecological management in the middle Yellow River, appropriate management strategies should be implemented based on the vulnerability characteristics of different natural landforms, to further improve the ecological management level of the watershed.

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