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1.
Nucleic Acids Res ; 52(D1): D115-D123, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37823705

RESUMO

Circular RNAs (circRNAs) are RNA molecules with a continuous loop structure characterized by back-splice junctions (BSJs). While analyses of short-read RNA sequencing have identified millions of BSJ events, it is inherently challenging to determine exact full-length sequences and alternatively spliced (AS) isoforms of circRNAs. Recent advances in nanopore long-read sequencing with circRNA enrichment bring an unprecedented opportunity for investigating the issues. Here, we developed FL-circAS (https://cosbi.ee.ncku.edu.tw/FL-circAS/), which collected such long-read sequencing data of 20 cell lines/tissues and thereby identified 884 636 BSJs with 1 853 692 full-length circRNA isoforms in human and 115 173 BSJs with 135 617 full-length circRNA isoforms in mouse. FL-circAS also provides multiple circRNA features. For circRNA expression, FL-circAS calculates expression levels for each circRNA isoform, cell line/tissue specificity at both the BSJ and isoform levels, and AS entropy for each BSJ across samples. For circRNA biogenesis, FL-circAS identifies reverse complementary sequences and RNA binding protein (RBP) binding sites residing in flanking sequences of BSJs. For functional patterns, FL-circAS identifies potential microRNA/RBP binding sites and several types of evidence for circRNA translation on each full-length circRNA isoform. FL-circAS provides user-friendly interfaces for browsing, searching, analyzing, and downloading data, serving as the first resource for discovering full-length circRNAs at the isoform level.


Assuntos
Bases de Dados de Ácidos Nucleicos , RNA Circular , Animais , Humanos , Camundongos , Processamento Alternativo/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Sequenciamento por Nanoporos , RNA Circular/genética , Isoformas de RNA/genética
2.
RNA ; 29(5): 557-569, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36737102

RESUMO

PIWI-interacting RNAs (piRNAs) protect genome integrity by silencing transposon mRNAs and some endogenous mRNAs in various animals. However, C. elegans piRNAs only trigger gene silencing at select predicted targeting sites, suggesting additional cellular mechanisms regulate piRNA silencing. To gain insight into possible mechanisms, we compared the transcriptome-wide predicted piRNA targeting sites to the in vivo piRNA binding sites. Surprisingly, while sequence-based predicted piRNA targeting sites are enriched in 3' UTRs, we found that C. elegans piRNAs preferentially bind to coding regions (CDS) of target mRNAs, leading to preferential production of secondary silencing small RNAs in the CDS. However, our analyses suggest that this CDS binding preference cannot be explained by the action of antisilencing Argonaute CSR-1. Instead, our analyses imply that CSR-1 protects mRNAs from piRNA silencing through two distinct mechanisms-by inhibiting piRNA binding across the entire CSR-1 targeted transcript, and by inhibiting secondary silencing small RNA production locally at CSR-1 bound sites. Together, our work identifies the CDS as the critical region that is uniquely competent for piRNA binding in C. elegans. We speculate the CDS binding preference may have evolved to allow the piRNA pathway to maintain robust recognition of RNA targets in spite of genetic drift. Together, our analyses revealed that distinct mechanisms are responsible for restricting piRNA binding and silencing to achieve proper transcriptome surveillance.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , RNA de Interação com Piwi , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transcriptoma , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , RNA de Cadeia Dupla/metabolismo , Sítios de Ligação , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo
3.
J Am Chem Soc ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38917169

RESUMO

The receptor for advanced glycation end products (RAGE) plays a crucial role in inflammation-related pathways and various chronic diseases. Despite the recognized significance of N-glycosylation in the ligand-binding V domain (VD) of RAGE, a comprehensive understanding of the site-activity and structure-activity relationships is lacking due to the challenges in obtaining homogeneous glycoprotein samples through biological expression. Here, we combined chemical and chemoenzymatic approaches to synthesize RAGE-VD and its congeners with Asn3-glycosylation by incorporating precise N-glycan structures. Evaluation of these samples revealed that, in comparison to other RAGE-VD forms, α2,6-sialylated N-glycosylation at the Asn3 site results in more potent inhibition of HMGB1-induced nuclear factor-κB (NF-κB) expression in RAGE-overexpressing cells. Hydrogen/deuterium exchange-mass spectrum analysis revealed a sialylated RAGE-VD-induced interaction region within HMGB1. Conversely, Asn3 N-glycosylation in VD has negligible effects on RAGE-VD/S100B interactions. This study established an approach for accessing homogeneously glycosylated RAGE-VD and explored the modulatory effects of N-glycosylation on the interactions between RAGE-VD and its ligand proteins.

4.
Biochem Biophys Res Commun ; 696: 149494, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38219491

RESUMO

Skeletal muscle is the largest metabolic tissue responsible for systemic glucose handling. Glucose uptake into skeletal tissue is highly dynamic and delicately regulated, in part through the controlled expression and subcellular trafficking of multiple types of glucose transporters. Although the roles of GLUT4 in skeletal muscle metabolism are well established, the physiological significance of other, seemingly redundant, glucose transporters remain incompletely understood. Nonetheless, recent studies have shed light on the roles of several glucose transporters, such as GLUT1 and GLUT10, in skeletal muscle. Mice experiments suggest that GLUT10 could be a novel player in skeletal muscle metabolism in the context of mechanical overload, which is in line with the meta-analytical results of gene expression changes after resistance exercise in humans. Herein we discuss the knowns, unknowns, and implications of these recent findings.


Assuntos
Proteínas Facilitadoras de Transporte de Glucose , Proteínas de Transporte de Monossacarídeos , Animais , Humanos , Camundongos , Transporte Biológico , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/genética , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Insulina/metabolismo , Proteínas de Transporte de Monossacarídeos/genética , Músculo Esquelético/metabolismo
5.
J Synchrotron Radiat ; 31(Pt 1): 195-201, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038695

RESUMO

The Photoelectron-Related Image and Nano-Spectroscopy (PRINS) endstation located at the Taiwan Photon Source beamline 27A2 houses a photoelectron momentum microscope capable of performing direct-space imaging, momentum-space imaging and photoemission spectroscopy with position sensitivity. Here, the performance of this microscope is demonstrated using two in-house photon sources - an Hg lamp and He(I) radiation - on a standard checkerboard-patterned specimen and an Au(111) single crystal, respectively. By analyzing the intensity profile of the edge of the Au patterns, the Rashba-splitting of the Au(111) Shockley surface state at 300 K, and the photoelectron intensity across the Fermi edge at 80 K, the spatial, momentum and energy resolution were estimated to be 50 nm, 0.0172 Å-1 and 26 meV, respectively. Additionally, it is shown that the band structures acquired in either constant energy contour mode or momentum-resolved photoemission spectroscopy mode were in close agreement.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38696753

RESUMO

OBJECTIVE: To evaluate the risk of end-stage kidney disease (ESKD) in lupus nephritis (LN) patients using tubulointerstitial lesion scores. METHODS: Clinical profiles and histopathological presentations of 151 biopsy-proven LN patients were retrospectively examined. Risk factors of ESKD based on characteristics and scoring of their tubulointerstitial lesions (e.g. interstitial inflammation [II], tubular atrophy [TA], and interstitial fibrosis [IF]) were analyzed. RESULTS: The mean age of 151 LN patients was 36 years old, and 136 (90.1%) were female. The LN cases examined included: class I/II (n = 3, 2%), class III/IV (n = 119, 78.8%), class V (n = 23, 15.2%), and class VI (n = 6, 4.0%). The mean serum creatinine level was 1.4 mg/dl. Tubulointerstitial lesions were recorded in 120 (79.5%) patients. Prior to receiving renal biopsy, 9 (6.0%) patients developed ESKD. During the follow-up period (mean, 58 months), an additional 47 patients (31.1%) progressed to ESKD. Multivariate analyses identified serum creatinine (hazard ratio [HR]: 1.7, 95% confidence interval [CI]: 1.42-2.03, p < 0.001) and IF (HR: 3.2, 95% CI: 1.58-6.49, p = 0.001) as independent risk factors of ESKD. Kaplan-Meier analysis further confirmed a heightened risk of ESKD associated with IF. CONCLUSION: Tubulointerstitial involvement is commonly observed in histopathological presentation of LN. However, IF, rather than II, or TA, was found to increase the risk of ESKD in our cohort. Therefore, to predict renal outcome in LN patients prior to adjusting immunosuppressive treatment, degree of IF should be reviewed.

7.
Exp Dermatol ; 33(1): e15012, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284204

RESUMO

Phototherapy is a useful treatment modality for atopic dermatitis (AD). This is a prospective randomised double-blind study comparing the clinical efficacy of combined ultraviolet-A (UVA)/narrowband ultraviolet-B (NBUVB) versus NBUVB phototherapy in the treatment of chronic AD. Patients with moderate-to-severe AD were randomised to receive either UVA/NBUVB or NBUVB phototherapy twice weekly over 12 weeks. At baseline, weeks 6 and 12, Eczema Area And Severity Index (EASI), itch score and adverse effects were assessed. At baseline and week 12, disease-related quality of life was evaluated using the Dermatology Life Quality Index (DLQI). Nine patients were randomised to receive UVA/NBUVB and 10 received NBUVB. At week 12, both groups showed significant improvement in EASI and itch scores (p < 0.05). Significant improvement in DLQI was seen in the UVA/NBUVB arm (p = 0.009) with a trend towards improvement in the NBUVB arm (p = 0.11). The efficacy of both modalities were comparable, as were reported adverse effects aside from skin dryness which was higher in the NBUVB arm (40% vs. 0%, p = 0.033). Combined UVA/NBUVB and NBUVB phototherapy have comparable clinical efficacy and safety in the treatment of chronic AD. NBUVB may induce greater skin dryness.


Assuntos
Dermatite Atópica , Eczema , Terapia Ultravioleta , Humanos , Dermatite Atópica/radioterapia , Estudos Prospectivos , Método Duplo-Cego , Qualidade de Vida , Terapia Ultravioleta/efeitos adversos , Fototerapia , Prurido/etiologia , Prurido/radioterapia , Resultado do Tratamento
8.
Chemistry ; 30(2): e202302458, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37861104

RESUMO

As a crucial class of functional molecules in organosilicon chemistry, silanols are found valuable applications in the fields of modern science and will be a potentially powerful framework for biologically active compounds or functional materials. It has witnessed an increasing demand for non-natural organosilanols, as well as the progress in the synthesis of these structural features. From the classic preparative methods to the catalytic selective oxidation of hydrosilanes, electrochemical hydrolysis of hydrosilanes, and then the construction of the most challenging silicon-stereogenic silanols. This review summarized the progress in the catalyzed synthesis of silanols via hydroxylation of hydrosilanes in the last decade, with a particular emphasis on the latest elegant developments in the desymmetrization strategy for the enantioselective synthesis of silicon-stereogenic silanols from dihydrosilanes.

9.
J Rheumatol ; 51(2): 160-167, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37839817

RESUMO

OBJECTIVE: To evaluate the risk and protective factors of serious infection (SI) in patients with systemic lupus erythematosus (SLE) within 180 days of rituximab (RTX) treatment. METHODS: Patients with SLE treated with RTX were analyzed. SI was defined as any infectious disease requiring hospitalization. The clinical characteristics, laboratory profiles, medications, and incidence rate (IR) are presented. Multivariate Cox proportional hazards models and Kaplan-Meier analysis for risk factors of SI were performed. RESULTS: A total of 174 patients with SLE receiving RTX treatment were enrolled. The overall IR of SIs was 51.0/100 patient-years (PYs). Pneumonia (30.4/100 PYs), followed by soft tissue infections, intra-abdominal infections, and Pneumocystis jiroveci pneumonia (all 6.1/100 PYs) were the leading types of SIs. Twelve patients died during the 180-day follow-up (crude mortality rate: 14.6/100 PYs). Chronic kidney disease (CKD), defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m2 (hazard ratio [HR] 2.88, 95% CI 1.30-6.38), and a background prednisolone (PSL) equivalent dosage ≥ 15 mg/day (HR 3.50, 95% CI 1.57-7.78) were risk factors for SIs among all patients with SLE. Kaplan-Meier analysis confirmed the risk of SI for patients with SLE with CKD and a background PSL equivalent dosage ≥ 15 mg/day (log-rank P = 0.001 and 0.02, respectively). Hydroxychloroquine (HCQ) reduced the risk of SIs in patients with SLE (HR 0.35, 95% CI 0.15-0.82; log-rank P = 0.003). CONCLUSION: SI was prevalent in patients with SLE after RTX treatment. Patients with SLE with CKD and high-dose glucocorticoid use required constant vigilance. HCQ may reduce the risk of SI among patients with SLE administered RTX.


Assuntos
Lúpus Eritematoso Sistêmico , Pneumonia por Pneumocystis , Insuficiência Renal Crônica , Humanos , Rituximab/efeitos adversos , Incidência , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/epidemiologia , Hidroxicloroquina/uso terapêutico , Fatores de Risco , Prednisolona/uso terapêutico , Pneumonia por Pneumocystis/epidemiologia
10.
PLoS Biol ; 19(4): e3001194, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33872303

RESUMO

Persisters represent a small subpopulation of non- or slow-growing bacterial cells that are tolerant to killing by antibiotics. Despite their prominent role in the recalcitrance of chronic infections to antibiotic therapy, the mechanism of their formation has remained elusive. We show that sorted cells of Escherichia coli with low levels of energy-generating enzymes are better able to survive antibiotic killing. Using microfluidics time-lapse microscopy and a fluorescent reporter for in vivo ATP measurements, we find that a subpopulation of cells with a low level of ATP survives killing by ampicillin. We propose that these low ATP cells are formed stochastically as a result of fluctuations in the abundance of energy-generating components. These findings point to a general "low energy" mechanism of persister formation.


Assuntos
Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Ciclo do Ácido Cítrico/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Organismos Geneticamente Modificados
11.
Langmuir ; 40(9): 4845-4851, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38373703

RESUMO

The gradual guidance of the formation of metal-organic structures through surface-based Cu atoms for 1,4-diaminoanthraquinones (DAQs) has been studied by scanning tunneling microscopy (STM) at room temperature. On the Ag(110) surface, the transition from a hydrogen-bond network structure to metal-organic coordination structures of DAQs can be induced by introducing foreign copper atoms. Due to the weak interaction between DAQs and Ag(110), thermal treatment easily leads to the desorption of DAQs from the surface. To address this challenge, Cu(111) is selected as the substrate. Under thermal driving and in the presence of copper adatoms, the hydrogen-bond network structure of DAQs on the surface gradually undergoes a transition into a metal-coordinated structure, eventually leading to the formation of metal-organic complexes through amino dehydrogenation. It is demonstrated that the construction of a metal-organic coordination structure on metal surfaces is a result of the competition among factors such as metal atoms, functional groups of molecules, surface chemical activity, and temperature.

12.
Langmuir ; 40(1): 1072-1078, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38154099

RESUMO

The delicate regulation of structural phase transition can provide advanced approaches for fabricating desired and well-organized nanoarchitectures on surfaces. Introduction of metal ions into pure organic systems can facilitate the phase transition from hydrogen-bonded structures to metal-organic structures by coordinating with organic molecules. However, it remains a challenge to attain a phase transition dominated by variable metal coordination configurations through adjustment of the metal ion concentration. Herein, we report the phase transitions of naphthalene-2,3-carbonitride (2,3-DCN) molecules on highly oriented pyrolytic graphite (HOPG) under varying solvents and Cu2+ ion concentrations. By integrating data from scanning tunneling microscopy imaging and density functional theory calculations, it is demonstrated that phase transitions of 2,3-DCN occur through forming diverse coordination configurations where Cu2+ ions can coordinate with 2,3-DCN and 1-nonanoic acid or Cl- ions to form different ligand components with a coordination number of 4 when varying the molar ratios of 2,3-DCN to Cu2+ ion in the 1-nonanoic acid solvent. However, in the case of 1-heptanoic acid as a solvent, the self-assembly structure of 2,3-DCN only changes via the alteration of hydrogen bonding sites and Cu2+ ions do not coordinate with 2,3-DCN molecules. These findings provide valuable insights into the coordination behavior of metal ions in different solvents.

13.
J Chem Inf Model ; 64(7): 2445-2453, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37903033

RESUMO

miRNAs (microRNAs) target specific mRNA (messenger RNA) sites to regulate their translation expression. Although miRNA targeting can rely on seed region base pairing, animal miRNAs, including human miRNAs, typically cooperate with several cofactors, leading to various noncanonical pairing rules. Therefore, identifying the binding sites of animal miRNAs remains challenging. Because experiments for mapping miRNA targets are costly, computational methods are preferred for extracting potential miRNA-mRNA fragment binding pairs first. However, existing prediction tools can have significant false positives due to the prevalent noncanonical miRNA binding behaviors and the information-biased training negative sets that were used while constructing these tools. To overcome these obstacles, we first prepared an information-balanced miRNA binding pair ground-truth data set. A miRNA-mRNA interaction-aware model was then designed to help identify miRNA binding events. On the test set, our model (auROC = 94.4%) outperformed existing models by at least 2.8% in auROC. Furthermore, we showed that this model can suggest potential binding patterns for miRNA-mRNA sequence interacting pairs. Finally, we made the prepared data sets and the designed model available at http://cosbi2.ee.ncku.edu.tw/mirna_binding/download.


Assuntos
MicroRNAs , Animais , Humanos , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Algoritmos , Biologia Computacional/métodos
14.
Nanotechnology ; 35(12)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38061057

RESUMO

In this article, a 0.7 nm thick monolayer MoS2nanosheet gate-all-around field effect transistors (NS-GAAFETs) with conformal high-κmetal gate deposition are demonstrated. The device with 40 nm channel length exhibits a high on-state current density of ~410µAµm-1with a large on/off ratio of 6 × 108at drain voltage = 1 V. The extracted contact resistance is 0.48 ± 0.1 kΩµm in monolayer MoS2NS-GAAFETs, thereby showing the channel-dominated performance with the channel length scaling from 80 to 40 nm. The successful demonstration of device performance in this work verifies the integration potential of transition metal dichalcogenides for future logic transistor applications.

15.
Environ Sci Technol ; 58(11): 4914-4925, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38436231

RESUMO

Particulate matter, especially PM2.5, can invade the central nervous system (CNS) via the olfactory pathway to induce neurotoxicity. The olfactory bulb (OB) is the key component integrating immunoprotection and olfaction processing and is necessarily involved in the relevant CNS health outcomes. Here we show that a microglial chemokine receptor, CCR5, is the target of environmentally relevant PM2.5 in the OB to trigger neuroinflammation and then neuropathological injuries. Mechanistically, PM2.5-induced CCR5 upregulation results in the pro-inflammatory paradigm of microglial activation, which subsequently activates TLR4-NF-κB neuroinflammation signaling and induces neuropathological changes that are closely related to neurodegenerative disorders (e.g., Aß deposition and disruption of the blood-brain barrier). We specifically highlight that manganese and lead in PM2.5 are the main contributors to CCR5-mediated microglial activation and neuroinflammation in synergy with aluminum. Our results uncover a possible pathway of PM2.5-induced neuroinflammation and identify the principal neurotoxic components, which can provide new insight into efficiently diminishing the adverse health effects of PM2.5.


Assuntos
Doenças Neuroinflamatórias , Bulbo Olfatório , Camundongos , Animais , Bulbo Olfatório/metabolismo , Material Particulado/toxicidade , Transdução de Sinais , Receptores de Quimiocinas/metabolismo , NF-kappa B/metabolismo , NF-kappa B/farmacologia
16.
Support Care Cancer ; 32(2): 116, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38240819

RESUMO

OBJECTIVE: Hospice care ensures better end-of-life quality by relieving terminal symptoms. Prior research has indicated that hospice care could prolong survival and reduce end-of-life medical expenditures among patients with cancer. However, the dearth of studies on the effects of hospice care type and use sequence on survival time and end-of-life medical expenditures substantiates the need for investigation. DATA SOURCES AND STUDY SETTING: Two million random records were obtained from the National Health Insurance Research Database. STUDY DESIGN: We estimated the effects of the type and sequence of hospice care use on survival time and medical expenditures among advanced cancer patients. This was a cross-sectional study. DATA COLLECTION/EXTRACTION METHODS: Patient data were collected from 2 million random records provided by the National Health Insurance Research Database of Taiwan. We included people with cancer and excluded patients under 20 years of age; 2860 patients remained after matching. PRINCIPAL FINDINGS: The results indicated that the average survival time of patients who received inpatient palliative care (1022 days) was significantly shorter than that of patients who did not receive palliative care (P < 0.001), but the health care expenditure during the entire course of cancer therapy was not the lowest. Interestingly, patients who received inpatient palliative care had the lowest health care expenditure at 1 year or month before the end of life (P < 0.001). CONCLUSION: The type and sequence of palliative care affected the survival time and health care expenditures of cancer patients. Receiving palliative care did not prolong survival but rather reduced health care expenditures. The sequence of receiving palliative care significantly affected health care expenditures.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Neoplasias , Assistência Terminal , Humanos , Cuidados Paliativos/métodos , Gastos em Saúde , Estudos Transversais , Assistência Terminal/métodos , Neoplasias/terapia , Morte
17.
Mol Ther ; 31(3): 825-846, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638800

RESUMO

Blindness caused by advanced stages of inherited retinal diseases and age-related macular degeneration are characterized by photoreceptor loss. Cell therapy involving replacement with functional photoreceptor-like cells generated from human pluripotent stem cells holds great promise. Here, we generated a human recombinant retina-specific laminin isoform, LN523, and demonstrated the role in promoting the differentiation of human embryonic stem cells into photoreceptor progenitors. This chemically defined and xenogen-free method enables reproducible production of photoreceptor progenitors within 32 days. We observed that the transplantation into rd10 mice were able to protect the host photoreceptor outer nuclear layer (ONL) up to 2 weeks post transplantation as measured by full-field electroretinogram. At 4 weeks post transplantation, the engrafted cells were found to survive, mature, and associate with the host's rod bipolar cells. Visual behavioral assessment using the water maze swimming test demonstrated visual improvement in the cell-transplanted rodents. At 20 weeks post transplantation, the maturing engrafted cells were able to replace the loss of host ONL by extensive association with host bipolar cells and synapses. Post-transplanted rabbit model also provided congruent evidence for synaptic connectivity with the degenerated host retina. The results may pave the way for the development of stem cell-based therapeutics for retina degeneration.


Assuntos
Células-Tronco Pluripotentes , Degeneração Retiniana , Humanos , Camundongos , Animais , Coelhos , Laminina/genética , Retina , Células Fotorreceptoras , Degeneração Retiniana/genética , Degeneração Retiniana/terapia , Diferenciação Celular
18.
Chem Biodivers ; : e202400635, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687253

RESUMO

The phytochemical investigation of the fruits of Cornus officinalis yielded a new phenolic acid derivative, neophenolic acid A (1), and a novel flavonoid glycoside, (2R)-naringenin-7-O-ß-(6''-galloyl-glucopyranoside) (2 a), along with six known flavonoid glycosides (2 b-7). Their structures were determined by 1D, 2D NMR and HRESIMS data. The absolute configuration of 1 was established by ECD analysis. Compounds 1- 7 were evaluated for their neuroprotective activities against corticosterone (CORT)-induced injury in PC-12 cells. Compounds 1, 2 a, 2 b, 5, and 6 exhibited neuroprotective activities against CORT-induced neurotoxicity in PC-12 cells. The underlying mechanism study suggested that compounds 1, 2 a, 2 b, 5, and 6 were able to attenuate CORT-induced apoptosis and damage, increase the levels of MMP and decrease Ca2+ inward flow in PC-12 cells.

19.
BMC Med Educ ; 24(1): 349, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553678

RESUMO

BACKGROUND: Clinical practicum is crucial for strengthening nursing students' clinical competence. However, nursing students often experience considerable stress during clinical practicum, and so they employ coping strategies to alleviate it. There is almost no empirical evidence on the change trajectory of perceived stress, coping strategies, and clinical competence among nursing students during a one-year clinical practicum. This study aimed to investigate the trajectory of change in perceived stress, coping strategies, and clinical competence among undergraduate nursing students during a one-year clinical practicum. METHODS: This study used a longitudinal cohort design. Undergraduate nursing students were recruited from a science and technology university in Taiwan to participate from February 2021 to January 2022. Perceived stress, coping strategies, and clinical competence among students in basic training practicum (T1), advanced training practicum (T2), and comprehensive clinical nursing practicum (T3) were surveyed by using the Perceived Stress Scale (PSS), Coping Behaviour Inventory (CBI), and Clinical Competence Scale (CCS). PSS, CBI, and CCS in T1, T2, and T3 were compared using a generalized estimating equation (GEE) to deal with correlated data. The level of statistical significance was set at α = 0.05. RESULTS: A total of 315 undergraduate nursing students completed the questionnaire. The study results show that the overall perceived stress of the students is the highest in T2 and the lowest in T3. The main source of stress of the students is 'taking care of patients' at T1 and 'lack of professional knowledge and skills' at T2 and T3. Students' perceived stress in 'taking care of patients' gradually decreases over time. The four coping strategies of CBI, which are 'stay optimistic', 'problem-solving', 'transference' and 'avoidance' in this order, remain the same ranking in three surveys.The main stress coping strategy used by students is 'stay optimistic', while the coping strategy 'avoidance' is used more frequently in T2 than in T1 and T3. Students' mean scores of the overall clinical competence and in the 'general nursing' and 'management' subscales in T3 are higher than those in T1 and T2. However, their mean scores in 'self-growth' and 'positivity' subscales are the highest in T1 and the lowest in T2. CONCLUSIONS: The results show that through experiential learning in clinical practicum at different stages time after time, students' overall perceived stress is the lowest and their overall clinical competence is the highest in T3. The main coping strategy used when students managed stress is 'stay optimistic'. According to the results, we suggest that clinical educators provide students with appropriate guidance strategies at different stages of stress and continue to follow up the clinical competence and retention rates of these nursing students in the workplace in the future.


Assuntos
Bacharelado em Enfermagem , Testes Psicológicos , Autorrelato , Estudantes de Enfermagem , Humanos , Capacidades de Enfrentamento , Estudos Longitudinais , Bacharelado em Enfermagem/métodos , Competência Clínica , Preceptoria , Estresse Psicológico
20.
BMC Med Educ ; 24(1): 705, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943116

RESUMO

BACKGROUND: Entrustable Professional Activities (EPA)-based assessment is easily and intuitively used in evaluating the learning outcomes of competency-based medical education (CBME). This study aimed to develop an EPA for occupational therapy focused on providing health education and consultation (TP-EPA3) and examine its validity. METHODS: Nineteen occupational therapists who had completed online training on the EQual rubric evaluation participated in this study. An expert committee identified six core EPAs for pediatric occupational therapy. TP-EPA3 was developed following the EPA template and refined through consensus meetings. The EQual rubric, a 14-item, five-point criterion-based anchor system, encompassing discrete units of work (DU), entrustable, essential, and important tasks of the profession (EEIT), and curricular role (CR), was used to evaluate the quality of TP-EPA3. Overall scores below 4.07, or scores for DU, EEIT, and CR domains below 4.17. 4.00, and 4.00, respectively, indicate the need for modifications. RESULTS: The TP-EPA3 demonstrated good validity, surpassing the required cut-off score with an average overall EQual score of 4.21 (SD = 0.41). Specific domain scores for DU, EEIT, and CR were 3.90 (SD = 0.69), 4.46 (SD = 0.44), and 4.42 (SD = 0.45), respectively. Subsequent revisions clarified observation contexts, enhancing specificity and focus. Further validation of the revised TP-EPA3 and a thorough examination of its reliability and validity are needed. CONCLUSION: The successful validation of TP-EPA3 suggests its potential as a valid assessment tool in occupational therapy education, offering a structured approach for developing competency in providing health education and consultation. This process model for EPA development and validation can guide occupational therapists in creating tailored EPAs for diverse specialties and settings.


Assuntos
Competência Clínica , Educação Baseada em Competências , Terapia Ocupacional , Humanos , Terapia Ocupacional/educação , Competência Clínica/normas , Reprodutibilidade dos Testes , Avaliação Educacional , Educação em Saúde , Encaminhamento e Consulta/normas , Currículo , Masculino , Feminino
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