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1.
Mol Cell ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38723633

RESUMO

Many multi-spanning membrane proteins contain poorly hydrophobic transmembrane domains (pTMDs) protected from phospholipid in mature structure. Nascent pTMDs are difficult for translocon to recognize and insert. How pTMDs are discerned and packed into mature, muti-spanning configuration remains unclear. Here, we report that pTMD elicits a post-translational topogenesis pathway for its recognition and integration. Using six-spanning protein adenosine triphosphate-binding cassette transporter G2 (ABCG2) and cultured human cells as models, we show that ABCG2's pTMD2 can pass through translocon into the endoplasmic reticulum (ER) lumen, yielding an intermediate with inserted yet mis-oriented downstream TMDs. After translation, the intermediate recruits P5A-ATPase ATP13A1, which facilitates TMD re-orientation, allowing further folding and the integration of the remaining lumen-exposed pTMD2. Depleting ATP13A1 or disrupting pTMD-characteristic residues arrests intermediates with mis-oriented and exposed TMDs. Our results explain how a "difficult" pTMD is co-translationally skipped for insertion and post-translationally buried into the final correct structure at the late folding stage to avoid excessive lipid exposure.

2.
Phytochemistry ; 222: 114110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663824

RESUMO

Molecular networking strategy-based prioritization of the isolation of the rarely studied soft coral Sinularia tumulosa yielded 14 sesquiterpenes. These isolated constituents consisted of nine different types of carbon frameworks, namely asteriscane, humulane, capillosane, seco-asteriscane, guaiane, dumortane, cadinane, farnesane, and benzofarnesane. Among them, situmulosaols A-C (1, 3 and 4) were previously undescribed ones, whose structures with absolute configurations were established by the combination of extensive spectral data analyses, quantum mechanical-nuclear magnetic resonance and time-dependent density functional theory electronic circular dichroism calculations, the Snatzke's method, and the modified Mosher's method. Notably, situmulosaol C (4) was the second member of capillosane-type sesquiterpenes. The plausible biogenetic relationships of these skeletally different sesquiterpenes were proposed. All sesquiterpenoids were evaluated for their antibacterial, cytotoxic and anti-inflammatory effects. The bioassay results showed compound 14 exhibited significant antibacterial activities against a variety of fish and human pathogenic bacteria with MIC90 values ranging from 3.6 to 33.8 µg/mL. Moreover, moderate cytotoxic effects against HEL cells for components 13 and 14 and moderate inhibitory effect on lipopolysaccharide-induced inflammatory responses in RAW264.7 cells for substance 13 were also observed.


Assuntos
Antozoários , Sesquiterpenos , Antozoários/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Animais , Camundongos , Estrutura Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , China , Células RAW 264.7 , Testes de Sensibilidade Microbiana , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Relação Estrutura-Atividade , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga
3.
Apoptosis ; 29(5-6): 835-848, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38573492

RESUMO

Oxaliplatin resistance poses a significant challenge in colorectal cancer (CRC) therapy, necessitating further investigation into the underlying molecular mechanisms. This study aimed to elucidate the regulatory role of SNHG4 in oxaliplatin resistance and ferroptosis in CRC. Our findings revealed that treatment with oxaliplatin led to downregulation of SNHG4 expression in CRC cells, while resistant CRC cells exhibited higher levels of SNHG4 compared to parental cells. Silencing SNHG4 attenuated oxaliplatin resistance and reduced the expression of resistance-related proteins MRD1 and MPR1. Furthermore, induction of ferroptosis effectively diminished oxaliplatin resistance in both parental and resistant CRC cells. Notably, ferroptosis induction resulted in decreased SNHG4 expression, whereas SNHG4 overexpression suppressed ferroptosis. Through FISH, RIP, and RNA pull-down assays, we identified the cytoplasmic localization of both SNHG4 and PTEN, establishing that SNHG4 directly targets PTEN, thereby reducing mRNA stability in CRC cells. Silencing PTEN abrogated the impact of SNHG4 on oxaliplatin resistance and ferroptosis in CRC cells. In vivo experiments further validated the influence of SNHG4 on oxaliplatin resistance and ferroptosis in CRC cells through PTEN regulation. In conclusion, SNHG4 promotes resistance to oxaliplatin in CRC cells by suppressing ferroptosis through instability of PTEN, thus serves as a target for patients with oxaliplatin-base chemoresistance.


Assuntos
Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Ferroptose , Oxaliplatina , PTEN Fosfo-Hidrolase , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Oxaliplatina/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino
4.
BMC Psychiatry ; 24(1): 331, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689265

RESUMO

BACKGROUND: To examine the factor structure and psychometric properties of the Patient Health Questionnaire for Adolescents (PHQ-A) in Chinese children and adolescents with major depressive disorder (MDD). METHODS: A total of 248 MDD patients aged between 12 and 18 years were recruited and evaluated by the Patient Health Questionnaire for Adolescents (PHQ-A), the Center for Epidemiological Survey Depression Scale (CES-D), the Mood and Feelings Questionnaire (MFQ), and the improved Clinical Global Impression Scale, Severity item (iCGI-S). Thirty-one patients were selected randomly to complete the PHQ-A again one week later. Confirmatory factor analysis (CFA) was used to test the construct validity of the scale. Reliability was evaluated by Macdonald Omega coefficient. Pearson correlation coefficient was used to assess the item-total correlation and the correlation of PHQ-A with CES-D and MFQ respectively. Spearman correlation coefficient was used to assess test-retest reliability. The optimal cut-off value, sensitivity, and specificity of the PHQ-A were achieved by estimating the Receiver Operating Characteristics (ROC) curve. RESULTS: CFA reported adequate loadings for all items, except for item 3. Macdonald Omega coefficient of the PHQ-A was 0.87. The Spearman correlation coefficient of the test-retest reliability was 0.70. The Pearson correlation coefficients of the PHQ-A with CES-D and MFQ were 0.87 and 0.85, respectively (p < 0.01). By taking the iCGI-S as the remission criteria for MDD, the optimal cut-off value, sensitivity and specificity of the PHQ-A were 7, 98.7%, 94.7% respectively. CONCLUSION: The PHQ-A presented as a unidimensional construct and demonstrated satisfactory reliability and validity among the Chinese children and adolescents with MDD. A cut-off value of 7 was suggested for remission.


Assuntos
Transtorno Depressivo Maior , Psicometria , Humanos , Adolescente , Masculino , Feminino , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Reprodutibilidade dos Testes , Criança , China , Análise Fatorial , Questionário de Saúde do Paciente , Inquéritos e Questionários/normas , Escalas de Graduação Psiquiátrica/normas , Sensibilidade e Especificidade , Povo Asiático/psicologia , População do Leste Asiático
5.
Nat Med ; 30(3): 810-817, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38454125

RESUMO

Age is a predominant risk factor for acute kidney injury (AKI), yet the biological mechanisms underlying this risk are largely unknown. Clonal hematopoiesis of indeterminate potential (CHIP) confers increased risk for several chronic diseases associated with aging. Here we sought to test whether CHIP increases the risk of AKI. In three population-based epidemiology cohorts, we found that CHIP was associated with a greater risk of incident AKI, which was more pronounced in patients with AKI requiring dialysis and in individuals with somatic mutations in genes other than DNMT3A, including mutations in TET2 and JAK2. Mendelian randomization analyses supported a causal role for CHIP in promoting AKI. Non-DNMT3A-CHIP was also associated with a nonresolving pattern of injury in patients with AKI. To gain mechanistic insight, we evaluated the role of Tet2-CHIP and Jak2V617F-CHIP in two mouse models of AKI. In both models, CHIP was associated with more severe AKI, greater renal proinflammatory macrophage infiltration and greater post-AKI kidney fibrosis. In summary, this work establishes CHIP as a genetic mechanism conferring impaired kidney function recovery after AKI via an aberrant inflammatory response mediated by renal macrophages.


Assuntos
Injúria Renal Aguda , Hematopoiese Clonal , Animais , Camundongos , Humanos , Hematopoiese Clonal/genética , Hematopoese/genética , Fatores de Risco , Envelhecimento/genética , Injúria Renal Aguda/genética , Mutação/genética
6.
J Clin Invest ; 134(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488009

RESUMO

Uncontrolled accumulation of extracellular matrix leads to tissue fibrosis and loss of organ function. We previously demonstrated in vitro that the DNA/RNA-binding protein fused in sarcoma (FUS) promotes fibrotic responses by translocating to the nucleus, where it initiates collagen gene transcription. However, it is still not known whether FUS is profibrotic in vivo and whether preventing its nuclear translocation might inhibit development of fibrosis following injury. We now demonstrate that levels of nuclear FUS are significantly increased in mouse models of kidney and liver fibrosis. To evaluate the direct role of FUS nuclear translocation in fibrosis, we used mice that carry a mutation in the FUS nuclear localization sequence (FUSR521G) and the cell-penetrating peptide CP-FUS-NLS that we previously showed inhibits FUS nuclear translocation in vitro. We provide evidence that FUSR521G mice or CP-FUS-NLS-treated mice showed reduced nuclear FUS and fibrosis following injury. Finally, differential gene expression analysis and immunohistochemistry of tissues from individuals with focal segmental glomerulosclerosis or nonalcoholic steatohepatitis revealed significant upregulation of FUS and/or collagen genes and FUS protein nuclear localization in diseased organs. These results demonstrate that injury-induced nuclear translocation of FUS contributes to fibrosis and highlight CP-FUS-NLS as a promising therapeutic option for organ fibrosis.


Assuntos
Esclerose Lateral Amiotrófica , RNA , Animais , Camundongos , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Mutação , DNA , Fibrose , Colágeno/metabolismo , Esclerose Lateral Amiotrófica/genética
7.
Mar Drugs ; 22(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38393066

RESUMO

The balance between bone-resorbing osteoclasts and bone-forming osteoblasts is essential for the process of bone remodeling. Excessive osteoclast differentiation plays a pivotal role in the pathogenesis of bone diseases such as rheumatoid arthritis and osteoporosis. In the present study, we examined whether 7,8-epoxy-11-sinulariolide acetate (Esa), a marine natural product present in soft coral Sinularia siaesensis, attenuates inflammation and osteoclastogenesis in vitro. The results indicated that Esa significantly inhibited lipopolysaccharide (LPS)-induced inflammation model of RAW264.7 cells and suppressed receptor activator for nuclear factor-κB ligand (RANKL)-triggered osteoclastogenesis. Esa significantly down-regulated the protein expression of iNOS, COX-2, and TNF-α by inhibiting the NF-κB/MAPK/PI3K pathways and reducing the release of reactive oxygen species (ROS) in RAW264.7 macrophages. Besides, Esa treatment significantly inhibited osteoclast differentiation and suppressed the expression of osteoclast-specific markers such as NFATC1, MMP-9, and CTSK proteins. These findings suggest that Esa may be a potential agent for the maintenance of bone homeostasis associated with inflammation.


Assuntos
Antozoários , Reabsorção Óssea , Diterpenos , Animais , Osteogênese , Fosfatidilinositol 3-Quinases/metabolismo , Diferenciação Celular , Osteoclastos , NF-kappa B/metabolismo , Inflamação/metabolismo , Antozoários/metabolismo , Ligante RANK/metabolismo , Fatores de Transcrição NFATC/metabolismo
8.
Hematology ; 29(1): 2307817, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38319083

RESUMO

OBJECTIVE: To analyze the current treatment status and prognostic regression of the chronic NK cell lymphoproliferative disorder (CLPD-NK). METHODS: We retrospectively analyzed the clinical features, treatment and prognosis of 18 patients with CLPD-NK who were treated at our Hospital between September 2016 and September 2022. RESULTS: Eighteen patients were included: three patients were treated with chemotherapy, five patients underwent immune-related therapy, one patient was treated with glucocorticoids alone, five patients were administered granulocyte colony-stimulating factor, blood transfusion therapy, or anti-infection therapy, followed by observation and follow-up, and four patients were observed without treatment. Fifteen patients survived, including two patients who achieved complete remission (CR) and seven patients who achieved partial remission (PR), of whom one patient progressed to Aggressive NK-cell leukemia (ANKL) and sustained remission after multiple lines of treatment; three patients were not reviewed, of which one patient was still in active disease, three patients developed hemophagocytic syndrome during treatment and eventually died, one of them had positive Epstein-Barr virus (EBV) expression. The 5-years overall survival rate was 83%. CONCLUSION: Most patients with CLPD-NK have inert progression and a good prognosis, whereas some patients have a poor prognosis after progressing to ANKL and combined with hemophagocytic syndrome. Abnormal NK cells invading the center suggest a high possibility of ANKL development, and immunosuppressants and hormones are effective treatments for this disease.


Assuntos
Infecções por Vírus Epstein-Barr , Leucemia Linfocítica Granular Grande , Leucemia , Linfo-Histiocitose Hemofagocítica , Transtornos Linfoproliferativos , Humanos , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , Estudos Retrospectivos , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/terapia , Prognóstico , Células Matadoras Naturais/metabolismo , Doença Crônica , Leucemia/metabolismo
9.
Angew Chem Int Ed Engl ; 63(16): e202317284, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38342760

RESUMO

In this study, a series of enantioenriched sp3-Ge/B bimetallic modules were successfully synthesized via an enantioselective copper-catalyzed hydroboration of carbagermatrane (Ge)-containing alkenes. Orthogonal cross-coupling selectivity under different Pd-catalyzed conditions was achieved in an enantiospecific manner. Notably, the chiral secondary Ge exhibited a remarkable transmetallation ability prior to primary or secondary Bpin. The effectiveness of this Ge/B bimetallic strategy was further demonstrated through the development of new functional small molecules with Aggregation-Induced Emission (AIE) and Circularly Polarized Luminescence (CPL) performance. This represents the first successful example of synthesis of enantioenriched alkylgermanium reagents that permit enantiospecific cross-coupling reactions.

10.
Postgrad Med J ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38211949

RESUMO

In recent years, immunotherapy strategies based on immune checkpoint inhibitors have yielded good efficacy in colorectal cancer (CRC)especially in colorectal cancer with microsatellite instability-high. However, microsatellite-stable (MSS) CRCs account for about 85% of CRCs and are resistant to immunotherapy. Previous studies have shown that compared with MSS CRC, high microsatellite instability CRC possesses a higher frequency of mutations and can generate more neoantigens. Therefore, improving the sensitivity of immunotherapy to MSS CRC is a hot topic which is crucial for the treatment of MSS CRC. This review aims to discuss the factors contributing to MSS CRC insensitivity to immunotherapy and explored potential solutions to overcome immunotherapy resistance.

11.
BMC Infect Dis ; 24(1): 20, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166673

RESUMO

BACKGROUND: Bacterial vaginosis (BV) is a widely occurring vaginal inflammation in women of childbearing age caused by dysbiosis of the vaginal flora. Few studies have investigated the effect of serum carotenoids on the development and pathogenesis of BV. This study thus aimed to explore the correlation between serum carotenoids and BV in American women. METHOD: The analysis included 1252 participants with BV from the National Health and Nutrition Examination Survey (NHANES) between 2001 and 2004. Multiple logistic regression was conducted to explore the correlation between BV and serum carotenoids, while smooth curve fitting was utilized to examine potential nonlinear correlations. Furthermore, stratified subgroup analyses and sensitivity analyses were conducted. ORs reflected the correlation between BV and serum carotenoids. RESULT: Results of multiple logistic regression indicated that total serum carotenoids and BV had an inverse correlation. In the fully adjusted model II, the quartile with the highest levels of α-carotene and ß-cryptoxanthin had a substantially lower incidence of BV. Smooth curve fitting revealed a significant negative linear correlation between serum carotenoids and the incidence of BV. The negative correlation between serum carotenoids and BV was relatively stable in stratified analyses. Moreover, in sensitivity analyses, the association between serum carotenoids and BV persisted, and ß-carotene became significantly negatively correlated with BV. CONCLUSION: This study found an inverse correlation between serum carotenoids and the prevalence of BV.


Assuntos
Vaginose Bacteriana , Humanos , Feminino , Estados Unidos/epidemiologia , Inquéritos Nutricionais , Vaginose Bacteriana/epidemiologia , Carotenoides , beta Caroteno , Antioxidantes
12.
Mar Drugs ; 22(1)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276652

RESUMO

Five new cembrane-type diterpenes, lobocalines A-E (1-5), and four new steroids, lobocaloids A-D (9-12), along with six known related compounds (6-8 and 13-15) were isolated from the Yalong Bay soft coral Lobophytum catalai Tixier-Durivault. The structures of the new compounds were elucidated by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent density functional theory-electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction analyses and comparison with the reported spectroscopic data of known compounds. Further, with the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a. In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory concentration (MIC) values of 8.7 and 17.3 µg/mL, respectively. All the steroids exhibited antibacterial activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 µg/mL. Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus aureus, while compounds 8-12 have medium inhibitory effects on the pyocyanin production in Pseudomonas aeruginosa.


Assuntos
Antozoários , Diterpenos , Animais , Esteroides/farmacologia , Antibacterianos/farmacologia , Espectroscopia de Ressonância Magnética , Antozoários/química , Diterpenos/química , China , Estrutura Molecular
13.
Am J Physiol Renal Physiol ; 326(2): F219-F226, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38031732

RESUMO

Protease-activated receptor 4 (PAR4) is a G protein-coupled receptor activated by thrombin. In the platelet, response to thrombin PAR4 contributes to the predominant procoagulant microparticle formation, increased fibrin deposition, and initiation of platelet-stimulated inflammation. In addition, PAR4 is expressed in other cell types, including endothelial cells. Under inflammatory conditions, PAR4 is overexpressed via epigenetic demethylation of the PAR4 gene, F2RL3. PAR4 knockout (KO) studies have determined a role for PAR4 in ischemia-reperfusion injury in the brain, and PAR4 KO mice display normal cardiac function but present less myocyte death and cardiac dysfunction in response to acute myocardial infarction. Although PAR4 has been reported to be expressed within the kidney, the contribution of PAR4 to acute kidney injury (AKI) and chronic kidney disease (CKD) is not well understood. Here we report that PAR4 KO mice are protected against kidney injury in two mouse models. First, PAR4 KO mice are protected against induction of markers of both fibrosis and inflammation in two different models of kidney injury: 1) 7 days following unilateral ureter obstruction (UUO) and 2) an AKI-CKD model of ischemia-reperfusion followed by 8 days of contralateral nephrectomy. We further show that PAR4 expression in the kidney is low in the control mouse kidney but induced over time following UUO. PAR4 KO mice are protected against blood urea nitrogen (BUN) and glomerular filtration rate (GFR) kidney function pathologies in the AKI-CKD model. Following the AKI-CKD model, PAR4 is expressed in the collecting duct colocalizing with Dolichos biflorus agglutinin (DBA), but not in the proximal tubule with Lotus tetragonolobus lectin (LTL). Collectively, the results reported in this study implicate PAR4 as contributing to the pathology in mouse models of acute and chronic kidney injury.NEW & NOTEWORTHY The contribution of the thrombin receptor protease-activated receptor 4 (PAR4) to acute kidney injury (AKI) and chronic kidney disease (CKD) is not well understood. Here we report that PAR4 expression is upregulated after kidney injury and PAR4 knockout (KO) mice are protected against fibrosis following kidney injury in two mouse models. First, PAR4 KO mice are protected against unilateral ureter obstruction. Second, PAR4 KO mice are protected against an AKI-CKD model of ischemia-reperfusion followed by contralateral nephrectomy.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Animais , Camundongos , Injúria Renal Aguda/genética , Injúria Renal Aguda/patologia , Células Endoteliais/metabolismo , Fibrose , Inflamação/patologia , Isquemia/patologia , Rim/metabolismo , Camundongos Knockout , Receptores de Trombina/genética , Receptores de Trombina/metabolismo , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Traumatismo por Reperfusão/patologia , Trombina/metabolismo , Trombina/farmacologia
14.
Phytochemistry ; 219: 113960, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159620

RESUMO

The chemical investigation on the soft coral Sinularia brassica collected off Xuwen Country, Guangdong Province, China, has resulted in the isolation and characterization of three uncommon cycloamphilectane-type diterpenoids, namely sinucycloamtin A-C (1-3), along with two known analogues (5 and 6). In addition, compounds 2 and 3 were hydrolyzed and their hydrolytic derivative sinucycloamtin D (4) was obtained. The structures of these previously undescribed compounds were established on the basis of extensive spectroscopic analysis, X-ray diffraction analysis, chemical conversion, as well as the comparison with the literature reported data. Compounds 1-3 represented the first examples of benzene-containing cycloamphilectane-type diterpenoids isolated from soft coral of genus Sinularia. In the in vitro bioassays, all the isolated and derived diterpenoids exhibited significant antibacterial activities against the fish pathogenic bacteria Phoyobacterium damselae FP2244 and Streptococcus parauberis SPOF3K with MIC90 values ranging from 3.7 to 9.1 µM.


Assuntos
Antozoários , Brassica , Diterpenos , Animais , Estrutura Molecular , Antozoários/química , Diterpenos/química , China
15.
Org Lett ; 25(50): 9014-9019, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38063439

RESUMO

Photoinduced generation of phosphoranyl radicals offers a versatile strategy to access a variety of synthetically valuable radicals. A long-standing challenge remains in the regulation of phosphoranyl radical to undergo α-scission pathway, although the ß-scission mode has been intensively studied. We herein developed an unprecedented protocol for selective α-scission of the P(OH)R3 radical intermediate under photocatalytic conditions. This efficient P-C bond cleavage via α-scission of the P(OH)R3 radicals has been successfully utilized in the alkylation/fluoroalkylation of alkenes.

16.
An. psicol ; 39(3): 395-404, Oct-Dic, 2023. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-224941

RESUMO

La Hospital Anxiety and Depression Scale (HADS) [Escala Hospitalaria de Ansiedad y Depresión] es una herramienta ampliamente utilizada para detección de la depresión y la ansiedad en pacientes con enfermedades médicas. Este estudio tuvo como objetivo explorar las propiedades psicométricas de la HADS en la detección de pacientes con depresión mayor utilizando el método de la teoría de respuesta al ítem. Un total de 460 pacientes con depresión mayor completaron el HADS. Se utilizó el análisis de Rasch para examinar la unidimensionalidad, el ajuste de los ítems, la dependencia local, la confiabilidad, el orden de las categorías, el funcionamiento diferencial de los ítems (DIF) y la focalización. La HADS mostró una construcción bidimensional. Todos los ítems se ajustaban al modelo de Rasch. Tres pares de ítems mostraron una dependencia local menor pero desconsiderada. Ambas subescalas tuvieron una confiabilidad aceptable. Ninguno de los ítems mostró categorías desordenadas o DIF. Todos los ítems estaban bien dirigidos y los participantes con niveles altos y bajos de angustia fueron menos objetivo que aquellos con niveles moderados de angustia. Finalmente, se generó una tabla de conversión para transformar las puntuaciones brutas en medidas de intervalo. El HADS demostró propiedades psicométricas adecuadas para evaluar la depresión y la ansiedad en pacientes con depresión mayor. Fue más apropiado para evaluar niveles de angustia moderados que altos o bajos. La tabla de conversión se puede utilizar para una medición más precisa. Estos resultados pueden allanar el camino para métodos eficientes y sensibles para analizar la respuesta a los síntomas de depresión en la investigación y en la práctica clínica.(AU)


The Hospital Anxiety and Depression Scale (HADS) is a widely used screening tool for depression and anxiety in patients with medical ill-nesses. This study aimed to explore the psychometric properties of the HADS in screening for patients with major depression using item response theory method.A total of 460 patients with major depression completed the HADS. Rasch analyses were used to examine unidimensionality, item fit, local dependency, reliability, ordering of categories, differential item functioning (DIF)and targeting. The HADS showed a two-dimensional construct.All items fit the Rasch model.Three pairs of items showed mi-norbut inconsiderate local dependency.Both subscales had acceptable re-liability.None of the items displayed disordered categoriesor DIF.All items werewelltargeted, and participants with high and low levels of dis-tress were less targeted than those with moderate levels of distress.Finally, a conversion table to transform the raw scores into interval measures was generated. The HADS demonstrated adequate psychometric properties in assessing depression and anxiety in patients with major depression. It was more appropriate for assessing moderate than high or low levels of dis-tress.The conversion table can be used for more precise measurement.These results may pave the way for efficient and sensitive methods of ana-lyzing depression symptom response in research and in clinical practice.(AU)


Assuntos
Humanos , Escala de Ansiedade Frente a Teste , Questionário de Saúde do Paciente , Psicometria , Estresse Psicológico , Depressão , Saúde Mental
17.
Chem Sci ; 14(48): 14302-14307, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38098716

RESUMO

Birefringent crystals can manipulate the polarization state of lasers and have vital application in polarizers, optical isolators, phase compensators, etc. The design and synthesis of crystals with large birefringence remains a challenging task. To design crystals with large birefringence, we combine an unprecedented chloroiodate(v) group (IO2Cl2)- featuring large polarizability anisotropy and a strong stereochemically active lone pair (SCALP) with the π-conjugated 2-amino-5-chloropyridine group. The superior synergy effect of (IO2Cl2)- and 2-amino-5-chloropyridine groups produces a new birefringent crystal, namely (C5H6.16N2Cl0.84)(IO2Cl2). It exhibits remarkably large birefringence of 0.67 at 546 nm, far exceeding those of most visible birefringent materials reported. This work discovers the first chloroiodate(v) group and provides a new synthetic route for birefringent materials.

18.
J Fungi (Basel) ; 9(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38132755

RESUMO

In this study, we focused on grapevine-endophyte interactions and reprogrammed secondary metabolism in the host plant due to defense against the colonization of endophytes. Thus, the transcriptional responses of tissue cultured grapevine seedlings (Vitis vinifera L. cv.: Cabernet Sauvignon) to two fungal endophytes Epicoccum layuense R2-21 (Epi R2-21) and Alternaria alternata XHYN2 (Alt XHYN2) at three different time points (6 h, 6 d, 15 d) were analyzed. As expected, a total of 5748 and 5817 differentially expressed genes (DEGs) were separately initiated in Epi R2-21 and Alt XHYN2 symbiotic tissue cultured seedlings compared to no endophyte treatment. The up-regulated DEGs at all time points in Epi R2-21- or Alt XHYN2-treated seedlings were mainly enriched in the flavonoid biosynthesis, phenylpropanoid biosynthesis, phenylalanine metabolism, stilbenoid, diarylheptanoid and gingerol biosynthesis, and circadian rhythm-plant pathways. In addition, the up-regulated DEGs at all sampling times in Alt XHYN2-treated tissue cultured seedlings were enriched in the plant-pathogen interaction pathway, but appeared in Epi R2-21 symbiotic seedlings only after 15 d of treatment. The down-regulated DEGs were not enriched in any KEGG pathways after 6 h inoculation for Epi R2-21 and Alt XHYN2 treatments, but were enriched mainly in photosynthesis-antenna proteins and plant hormone signal transduction pathways at other sampling times. At three different time points, a total of 51 DEGs (all up-regulated, 1.33-10.41-fold) were involved in secondary metabolism, and 22 DEGs (all up-regulated, 1.01-8.40-fold) were involved in defense responses in endophytic fungi symbiotic tissue cultured seedlings. The protein-protein interaction (PPI) network demonstrated that genes encoding CHS (VIT_10s0042g00920, VIT_14s0068g00920, and VIT_16s0100g00910) and the VIT_11s0065g00350 gene encoding CYP73A mediated the defense responses, and might induce more defense-associated metabolites. These results illustrated the activation of stress-associated secondary metabolism in the host grapevine during the establishment of fungi-plant endophytism. This work provides avenues for reshaping the qualities and characteristics of wine grapes utilizing specific endophytes and better understanding plant-microbe interactions.

19.
Nat Commun ; 14(1): 7357, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37963889

RESUMO

Fibrosis is the progressive accumulation of excess extracellular matrix and can cause organ failure. Fibrosis can affect nearly every organ including kidney and there is no specific treatment currently. Although Epidermal Growth Factor Receptor (EGFR) signaling pathway has been implicated in development of kidney fibrosis, underlying mechanisms by which EGFR itself mediates kidney fibrosis have not been elucidated. We find that EGFR expression increases in interstitial myofibroblasts in human and mouse fibrotic kidneys. Selective EGFR deletion in the fibroblast/pericyte population inhibits interstitial fibrosis in response to unilateral ureteral obstruction, ischemia or nephrotoxins. In vivo and in vitro studies and single-nucleus RNA sequencing analysis demonstrate that EGFR activation does not induce myofibroblast transformation but is necessary for the initial pericyte/fibroblast migration and proliferation prior to subsequent myofibroblast transformation by TGF-ß or other profibrotic factors. These findings may also provide insight into development of fibrosis in other organs and in other conditions.


Assuntos
Nefropatias , Obstrução Ureteral , Animais , Humanos , Camundongos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Fibrose , Rim/metabolismo , Nefropatias/metabolismo , Miofibroblastos/metabolismo , Transdução de Sinais/fisiologia , Obstrução Ureteral/metabolismo
20.
bioRxiv ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37961690

RESUMO

Remove of mis-incorporated nucleotides ensures replicative fidelity. Although the ε-exonuclease DnaQ is a well-established proofreader in the model organism Escherichia coli, proofreading in mycobacteria relies on the polymerase and histidinol phosphatase (PHP) domain of replicative polymerase despite the presence of an alternative DnaQ homolog. Here, we show that depletion of DnaQ in Mycolicibacterium smegmatis results in increased mutation rate, leading to AT-biased mutagenesis and elevated insertions/deletions in homopolymer tract. We demonstrated that mycobacterial DnaQ binds to the b-clamp and functions synergistically with the PHP domain to correct replication errors. Further, we found that the mycobacterial DnaQ sustains replicative fidelity upon chromosome topological stress. Intriguingly, we showed that a naturally evolved DnaQ variant prevalent in clinical Mycobacterium tuberculosis isolates enables hypermutability and is associated with extensive drug resistance. These results collectively establish that the alternative DnaQ functions in proofreading, and thus reveal that mycobacteria deploy two proofreaders to maintain replicative fidelity.

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