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1.
FASEB J ; 37(2): e22773, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36629784

RESUMO

Alzheimer's disease (AD) and Parkinson's disease (PD) are age-dependent neurodegenerative disorders. There is a profound neuronal loss in the basal forebrain cholinergic system in AD and severe dopaminergic deficiency within the nigrostriatal pathway in PD. Swedish APP (APPSWE ) and SNCAA53T mutations promote Aß generation and α-synuclein aggregation, respectively, and have been linked to the pathogenesis of AD and PD. However, the mechanisms underlying selective cholinergic and dopaminergic neurodegeneration in AD and PD are still unknown. We demonstrated that APPSWE mutation enhanced Aß generation and increased cell susceptibility to Aß oligomer in cholinergic SN56 cells, whereas SNCAA53T mutations promoted aggregates formation and potentiated mutant α-synuclein oligomer-induced cytotoxicity in MN9D cells. Furthermore, syndecan-3 (SDC3) and fibroblast growth factor receptor-like 1 (FGFRL1) genes were differentially expressed in SN56 and MN9D cells carrying APPSWE or SNCAA53T mutation. SDC3 and FGFRL1 proteins were preferentially expressed in the cholinergic nucleus and dopaminergic neurons of APPSWE and SNCAA53T mouse models, respectively. Finally, the knockdown of SDC3 and FGFRL1 attenuated oxidative stress-induced cell death in SN56-APPSWE and MN9D-SNCAA53T cells. The results demonstrate that SDC3 and FGFRL1 mediated the specific effects of APPSWE and SNCAA53T on cholinergic and dopaminergic neurodegeneration in AD and PD, respectively. Our study suggests that SDC3 and FGFRL1 could be potential targets to alleviate the selective neurodegeneration in AD and PD.


Assuntos
Doença de Alzheimer , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Sindecana-3/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo
2.
FASEB J ; 37(6): e22971, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37171286

RESUMO

Both Down syndrome (DS) individuals and animal models exhibit hypo-cellularity in hippocampus and neocortex indicated by enhanced neuronal death and compromised neurogenesis. Ubiquitin-specific peptidase 25 (USP25), a human chromosome 21 (HSA21) gene, encodes for a deubiquitinating enzyme overexpressed in DS patients. Dysregulation of USP25 has been associated with Alzheimer's phenotypes in DS, but its role in defective neurogenesis in DS has not been defined. In this study, we found that USP25 upregulation impaired cell cycle regulation during embryonic neurogenesis and cortical development. Overexpression of USP25 in hippocampus promoted the neural stem cells to glial cell fates and suppressed neuronal cell fate by altering the balance between cyclin D1 and cyclin D2, thus reducing neurogenesis in the hippocampus. USP25-Tg mice showed increased anxiety/depression-like behaviors and learning and memory deficits. These results suggested that USP25 overexpression resulted in defective neurogenesis and cognitive impairments, which could contribute to the pathogenesis of DS. USP25 may be a potential pharmaceutical target for DS.


Assuntos
Disfunção Cognitiva , Síndrome de Down , Camundongos , Humanos , Animais , Camundongos Transgênicos , Neurogênese/fisiologia , Neurônios/patologia , Hipocampo/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Ubiquitina Tiolesterase/genética
3.
Mol Psychiatry ; 28(5): 2107-2121, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36754983

RESUMO

Psychosis is an abnormal mental condition that can cause patients to lose contact with reality. It is a common symptom of schizophrenia, bipolar disorder, sleep deprivation, and other mental disorders. Clinically, antipsychotic medications, such as olanzapine and clozapine, are very effective in treatment for psychosis. To investigate the neural circuit mechanism that is affected by antipsychotics and identify more selective therapeutic targets, we employed a strategy by using these effective antipsychotics to identify antipsychotic neural substrates. We observed that local injection of antipsychotics into the ventral tegmental area (VTA) could reverse the sensorimotor gating defects induced by MK-801 injection in mice. Using in vivo fiber photometry, electrophysiological techniques, and chemogenetics, we found that antipsychotics could activate VTA gamma-aminobutyric acid (GABA) neurons by blocking GABAA receptors. Moreover, we found that the VTAGABA nucleus accumbens (NAc) projection was crucially involved in such antipsychotic effects. In summary, our study identifies a novel therapeutic target for the treatment of psychosis and underscores the utility of a 'bedside-to-bench' approach for identifying neural circuits that influence psychotic disorders.

4.
BMC Anesthesiol ; 23(1): 88, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944937

RESUMO

STUDY OBJECTIVES: To assess the effect of dexmedetomidine (DEX) on postoperative sleep quality using polysomnography (PSG) to identify possible interventions for postoperative sleep disturbances. METHODS: An electronic search of PubMed/MEDLINE, EMBASE, Cochrane Library and Web of Science was conducted from database inception to November 20, 2022. Randomized controlled trials (RCTs) on the effect of DEX administration on postoperative sleep quality using PSG or its derivatives were included. No language restrictions were applied. The sleep efficiency index (SEI), arousal index (AI), percentages of stage N1, N2 and N3 of non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep were measured in our meta-analysis. RESULTS: Five studies, involving 381 participants were included. Administration of DEX significantly improved SEI, lowered AI, decreased the duration of stage N1 sleep and increased the duration of stage N2 sleep compared to placebo groups. There were no significant differences in the duration of stage N3 sleep and REM sleep. DEX administration lowered the postoperative Visual Analogue Scale (VAS) score and improved the Ramsay sedation score with no adverse effect on postoperative delirium (POD). However, high heterogeneity was observed in most of the primary and secondary outcomes. CONCLUSIONS: Our study provides support for the perioperative administration of DEX to improve postoperative sleep quality. The optimal dosage and overall effect of DEX on postoperative sleep quality require further investigation using large-scale randomized controlled trials.


Assuntos
Dexmedetomidina , Delírio do Despertar , Humanos , Qualidade do Sono , Ensaios Clínicos Controlados Aleatórios como Assunto , Delírio do Despertar/tratamento farmacológico
5.
BMC Musculoskelet Disord ; 24(1): 675, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620819

RESUMO

OBJECTIVE: Exploring the correlation between bone turnover marks (BTMs) with lumbar BMD in middle-aged populations. METHODS: The cross-sectional analysis fetched data came from NHANES. The level of serum bone alkaline phosphatase (sBAP) and urinary N-telopeptide (uNTx) were regarded as representative of bone turnover. Lumbar BMD was the outcome of the study. Multivariable linear regression models were utilized to detect the correlation of sBAP and uNTx with Lumbar BMD. RESULTS: The level of sBAP and uNTx was negatively correlated with lumbar BMD in every multivariable linear regression. For sBAP, this inverse correlation was stable in both men and women (P < 0.01). uNTx indicated a negative association after all relevant covariables were adjusted (P < 0.01). The men group remained the negative correlation in gender subgroup analysis (P < 0.01). CONCLUSION: This study indicated that the increased level of sBAP and uNTx associated with lumbar BMD decreased among middle-aged adults. This correlation could prompt researchers to explore further the relationship between bone turnover rate and BMD, which may provide information for the early detection of BMD loss and provide a new strategy for clinical practice.


Assuntos
Fosfatase Alcalina , Densidade Óssea , Adulto , Masculino , Pessoa de Meia-Idade , Feminino , Humanos , Estudos Transversais , Inquéritos Nutricionais , Remodelação Óssea
6.
Plant Dis ; 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36995762

RESUMO

Species of Gymnosporangium are major pathogenic rust fungi causing diseases and significant economic losses of plants in the Cupressaceae and Rosaceae family (Kern 1973). During our investigation of rust fungi in Qinghai Province, northwestern China, we found the spermogonial and aecial stages of Gymnosporangium species on Cotoneaster acutifolius. C. acutifolius is the woody plant that range in habit from ground-covers to airy shrubs and medium-sized trees(Rothleutner et al. 2016). Upon investigation in the field, the incidence of rust on C. acutifolius was 80% and 60% (n = 100) for 2020 and 2022, respectively. C. acutifolius leaves showing abundant aecia were collected from Batang forest area of Yushu (32.45°N, 97.19°E, alt. 3835 m), Qinghai, China, from August to October of both years. The rust makes its symptom first on the upper surface appearing yellow then dark brow, aggregated spermogonia in yellow-orange leaf spots. These spots enlarge gradually and displaying an orange-yellow and are often bordered by red concentric rings. In the later stage, many pale yellow, roestelioid aecia developed on the abaxial surfaces of the leaves or fruits. The morphology of this fungus was studied using light microscopy and scanning electron microscopy (JEOL, JSM-6360LV). Microscopic examination show that aecia are foliicolous, hypophyllous, roestelioid, and producing cylindrical peridia that are acuminate, splitting above and becoming some-what lacerate nearly to base, somewhat erect after dehiscence. Peridial cells are rhomboid, and 42 to 118 × 11-27µm(n=30). They have smooth outer walls and rugose inner and side walls with long obliquely arranged ridges. Aeciospores are ellipsoid, chestnut brown, 20 to 38 × 15 to 35 µm(n=30), wall densely and minutely verrucose, 1 to 3 µm thick, with 4 to 10 pores. Whole genomic DNA was extracted (Tian et al. 2004), and the internal transcribed spacer 2 (ITS2) region was amplified with the primer pair ITS3 (Gardes and Bruns 1993) and ITS4 (Vogler and Bruns 1998). The sequence of the amplified fragment was deposited in the GenBank database (GenBank Accession No. MW714871). A BLAST search of GenBank showed a high identity (> 99%) with the reference sequences of Gymnosporangium pleoporumGenBank Accession No. MH178659 and MH178658). G. pleoporum was first described from specimens in the telial stage found on Juniperus przewalskii, from Menyuan of Qinghai in China (Tao et al. 2020). In this study, the fungus G.pleoporum of spermogonial and aecial stages were collected from the C. acutifolius, we confirmed the alternate host of G. pleoporum based on DNA extraction results. To our knowledge, this is the first record of G. pleoporum causing rust disease on C. acutifolius. Because the alternate host can be infected by several different species of Gymnosporangium (Tao et al. 2020), further investigations are needed to verify heteroecious of the rust fungus.

7.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139196

RESUMO

Tartary buckwheat (Fagopyrum tataricum) is an important plant, utilized for both medicine and food. It has become a current research hotspot due to its rich content of flavonoids, which are beneficial for human health. Anthocyanins (ATs) and proanthocyanidins (PAs) are the two main kinds of flavonoid compounds in Tartary buckwheat, which participate in the pigmentation of some tissue as well as rendering resistance to many biotic and abiotic stresses. Additionally, Tartary buckwheat anthocyanins and PAs have many health benefits for humans and the plant itself. However, little is known about the regulation mechanism of the biosynthesis of anthocyanin and PA in Tartary buckwheat. In the present study, a bHLH transcription factor (TF) FtTT8 was characterized to be homologous with AtTT8 and phylogenetically close to bHLH proteins from other plant species. Subcellular location and yeast two-hybrid assays suggested that FtTT8 locates in the nucleus and plays a role as a transcription factor. Complementation analysis in Arabidopsis tt8 mutant showed that FtTT8 could not recover anthocyanin deficiency but could promote PAs accumulation. Overexpression of FtTT8 in red-flowering tobacco showed that FtTT8 inhibits anthocyanin biosynthesis and accelerates proanthocyanidin biosynthesis. QRT-PCR and yeast one-hybrid assay revealed that FtTT8 might bind to the promoter of NtUFGT and suppress its expression, while binding to the promoter of NtLAR and upregulating its expression in K326 tobacco. This displayed the bidirectional regulating function of FtTT8 that negatively regulates anthocyanin biosynthesis and positively regulates proanthocyanidin biosynthesis. The results provide new insights on TT8 in Tartary buckwheat, which is inconsistent with TT8 from other plant species, and FtTT8 might be a high-quality gene resource for Tartary buckwheat breeding.


Assuntos
Arabidopsis , Fagopyrum , Proantocianidinas , Humanos , Antocianinas/metabolismo , Proantocianidinas/metabolismo , Fagopyrum/genética , Fagopyrum/metabolismo , Proteínas de Plantas/metabolismo , Filogenia , Melhoramento Vegetal , Flavonoides/metabolismo , Plantas/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Arabidopsis/genética
8.
Minim Invasive Ther Allied Technol ; 32(1): 18-23, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36398905

RESUMO

PURPOSE: This study was designed to assess the clinical efficiency and long-term outcomes of hepatic vein (HV) and accessory hepatic vein (AHV) recanalization in patients with HV-type Budd-Chiari syndrome (BCS). MATERIAL AND METHODS: A total of 27 patients with HV-type BCS underwent AHV recanalization and 94 patients had HV recanalization at our center from January 2012 to December 2019. The treatment effectiveness and long-term outcomes were compared. RESULTS: Technical success was accomplished in all patients, without any procedure-related complications. The clinical success rates were 96.3% (26/27) and 95.7% (90/94) (p = 1.000). In the AHV and HV groups, re-obstruction was observed in 5 and 36 patients, respectively (p = 0.056). The median primary durations of AHV and HV patency were 64 and 49 months, respectively (p = 0.036), while the median secondary durations of AHV and HV patency were 70 and 64 months, respectively (p = 0.134). The median overall survival after AHV and HV recanalization was 73 and 78 months, respectively (p = 0.263). CONCLUSIONS: Our findings suggest that AHV could be employed as a replacement for HV, as a hepatic drainage vein, in HV-type BCS patients.


Assuntos
Síndrome de Budd-Chiari , Veias Hepáticas , Humanos , Veias Hepáticas/cirurgia , Síndrome de Budd-Chiari/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Veia Cava Inferior/cirurgia
9.
Funct Integr Genomics ; 22(6): 1449-1458, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36369301

RESUMO

Tartary buckwheat is among the valuable crops, utilized as both food and Chinese herbal medicine. To uncover the accumulation dynamics of the main nutrients and their regulatory mechanism of Tartary buckwheat seeds, microscopic observations and nutrient analysis were conducted which suggested that starch, proteins as well as flavonoid gradually accumulated among seed development. Comparative proteomic analysis of rice Tartary buckwheat at three different developmental stages was performed. A total of 78 protein spots showed differential expression with 74 of them being successfully identified by MALDI-TOF/TOF MS. Among them, granule bound starch synthase (GBSS1) might be the critical enzyme that determines starch biosynthesis, while 11 S seed storage protein and vicilin seemed to be the main globulin and affect seed storage protein accumulation in Tartary buckwheat seeds. Two enzymes, flavanone 3-hydroxylase (F3H) and anthocyanidin reductase (ANR), involved in the flavonoid biosynthesis pathway were identified. Further analysis on the expression profiles of flavonoid biosynthetic genes revealed that F3H might be the key enzyme that promote flavonoid accumulation. This study provides insights into the mechanism of nutrition accumulation at the protein level in Tartary buckwheat seeds and may facilitate in the breeding and enhancement of Tartary buckwheat germplasm.


Assuntos
Fagopyrum , Fagopyrum/genética , Fagopyrum/metabolismo , Proteômica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Melhoramento Vegetal , Sementes , Proteínas de Armazenamento de Sementes/genética , Amido/metabolismo , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Crit Care Med ; 50(3): 398-409, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34612846

RESUMO

OBJECTIVES: To explore candidate prognostic and predictive biomarkers identified in retrospective observational studies (interleukin-6, C-reactive protein, lactate dehydrogenase, ferritin, lymphocytes, monocytes, neutrophils, d-dimer, and platelets) in patients with coronavirus disease 2019 pneumonia after treatment with tocilizumab, an anti-interleukin-6 receptor antibody, using data from the COVACTA trial in patients hospitalized with severe coronavirus disease 2019 pneumonia. DESIGN: Exploratory analysis from a multicenter, randomized, double-blind, placebo-controlled, phase 3 trial. SETTING: Hospitals in North America and Europe. PATIENTS: Adults hospitalized with severe coronavirus disease 2019 pneumonia receiving standard care. INTERVENTION: Randomly assigned 2:1 to IV tocilizumab 8 mg/kg or placebo. MEASUREMENTS AND MAIN RESULTS: Candidate biomarkers were measured in 295 patients in the tocilizumab arm and 142 patients in the placebo arm. Efficacy outcomes assessed were clinical status on a seven-category ordinal scale (1, discharge; 7, death), mortality, time to hospital discharge, and mechanical ventilation (if not receiving it at randomization) through day 28. Prognostic and predictive biomarkers were evaluated continuously with proportional odds, binomial or Fine-Gray models, and additional sensitivity analyses. Modeling in the placebo arm showed all candidate biomarkers except lactate dehydrogenase and d-dimer were strongly prognostic for day 28 clinical outcomes of mortality, mechanical ventilation, clinical status, and time to hospital discharge. Modeling in the tocilizumab arm showed a predictive value of ferritin for day 28 clinical outcomes of mortality (predictive interaction, p = 0.03), mechanical ventilation (predictive interaction, p = 0.01), and clinical status (predictive interaction, p = 0.02) compared with placebo. CONCLUSIONS: Multiple biomarkers prognostic for clinical outcomes were confirmed in COVACTA. Ferritin was identified as a predictive biomarker for the effects of tocilizumab in the COVACTA patient population; high ferritin levels were associated with better clinical outcomes for tocilizumab compared with placebo at day 28.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Tratamento Farmacológico da COVID-19 , COVID-19/epidemiologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Biomarcadores , COVID-19/mortalidade , Método Duplo-Cego , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Tempo de Internação , Masculino , Alta do Paciente , Prognóstico , Respiração Artificial , SARS-CoV-2
11.
Acta Pharmacol Sin ; 43(7): 1829-1842, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34795411

RESUMO

Hydrogen sulfide (H2S) is widely recognized as the third endogenous gas signaling molecule and may play a key role in cancer biological processes. ADT-OH (5-(4-hydroxyphenyl)-3H-1,2-dithiocyclopentene-3-thione) is one of the most widely used organic donors for the slow release of H2S and considered to be a potential anticancer compound. In this study, we investigated the antimetastatic effects of ADT-OH in highly metastatic melanoma cells. A tail-vein-metastasis model was established by injecting B16F10 and A375 cells into the tail veins of mice, whereas a mouse footpad-injection model was established by injecting B16F10 cells into mouse footpads. We showed that administration of ADT-OH significantly inhibited the migration and invasion of melanoma cells in the three different animal models. We further showed that ADT-OH dose-dependently inhibited the migration and invasion of B16F10, B16F1 and A375 melanoma cells as evaluated by wound healing and Transwell assays in vitro. LC-MS/MS and bioinformatics analyses revealed that ADT-OH treatment inhibited the EMT process in B16F10 and A375 cells by reducing the expression of FAK and the downstream response protein Paxillin. Overexpression of FAK reversed the inhibitory effects of ADT-OH on melanoma cell migration. Moreover, after ADT-OH treatment, melanoma cells showed abnormal expression of the H2S-producing enzymes CSE/CBS and the AKT signaling pathways. In addition, ADT-OH significantly suppressed the proliferation of melanoma cells. Collectively, these results demonstrate that ADT-OH inhibits the EMT process in melanoma cells by suppressing the CSE/CBS and FAK signaling pathways, thereby exerting its antimetastatic activity. ADT-OH may be used as an antimetastatic agent in the future.


Assuntos
Melanoma , Tionas , Animais , Linhagem Celular Tumoral , Movimento Celular , Cromatografia Líquida , Quinase 1 de Adesão Focal/metabolismo , Melanoma/tratamento farmacológico , Camundongos , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/prevenção & controle , Paxilina , Transdução de Sinais , Neoplasias Cutâneas , Espectrometria de Massas em Tandem , Melanoma Maligno Cutâneo
12.
Mol Ther ; 29(1): 396-408, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-32950103

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder leading to dementia in the elderly, and the mechanisms of AD are not fully defined. MicroRNAs (miRNAs) have been shown to contribute to memory deficits in AD. In this study, we identified that miR-204-3p was downregulated in the hippocampus and plasma of 6-month-old APPswe/PS1dE9 (APP/PS1) mice. miR-204-3p overexpression attenuated memory and synaptic deficits in APP/PS1 mice. The amyloid levels and oxidative stress were decreased in the hippocampus of APP/PS1 mice after miR-204-3p overexpression. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (Nox4) was a target of miR-204-3p, and Nox4 inhibition by GLX351322 protected neuronal cells against Aß1-42-induced neurotoxicity. Furthermore, GLX351322 treatment rescued synaptic and memory deficits, and decreased oxidative stress and amyloid levels in the hippocampus of APP/PS1 mice. These results revealed that miR-204-3p attenuated memory deficits and oxidative stress in APP/PS1 mice by targeting Nox4, and miR-204-3p overexpression and/or Nox4 inhibition might be a potential therapeutic strategy for AD treatment.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Transtornos da Memória/etiologia , MicroRNAs/genética , NADPH Oxidase 4/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Biomarcadores , Modelos Animais de Doenças , Suscetibilidade a Doenças , Transtornos da Memória/diagnóstico , Camundongos , Camundongos Transgênicos , Estresse Oxidativo
13.
J Sep Sci ; 45(18): 3510-3519, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35880615

RESUMO

Chiral metal-organic frameworks have shown great potential in enantioselective separation and asymmetric catalysis due to their diverse and adjustable structures with abundant chiral recognition sites. Herein, a new chiral post-synthetic modification was used for preparing an achiral@chiral metal-organic frameworks core-shell composite [Cu3 (Btc)2 ]@[Cu2 ((+)-Cam)2 Dabco] by a superficial chiral etching method. The [Cu3 (Btc)2 ]@[Cu2 ((+)-Cam)2 Dabco] composite was utilized as a novel chiral stationary phase for HPLC enantioseparation. Various racemates were separated on the [Cu3 (Btc)2 ]@[Cu2 ((+)-Cam)2 Dabco]-packed column (column A). It exhibited good chiral resolving ability toward many different kinds of racemates, especially chiral drugs. Among them, the highest resolution value for 1,2-diphenyl-1,2-ethanediol reaches 2.70. The relative standard deviations of retention time and peak area for repeated separation of 1,2-diphenyl-1,2-ethanol were 0.45% and 0.81%, respectively. Compared with the resolution ability of [Cu2 ((+)-Cam)2 Dabco]-packed column (column B), column A shows higher column efficiency and better separation performance than those of column B. The results indicated that the [Cu3 (Btc)2 ]@[Cu2 ((+)-Cam)2 Dabco] as a stationary phase can greatly improve the column efficiency and chiral resolution ability of chiral metal-organic frameworks, which demonstrated that the superficial chiral etching as an economic and efficient strategy opens up a new way for the application of metal-organic frameworks.


Assuntos
Estruturas Metalorgânicas , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão/métodos , Etanol , Etilenoglicol , Estruturas Metalorgânicas/química , Estereoisomerismo
14.
Plant Dis ; 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35357180

RESUMO

Walnut (Juglans regia L.) is a high quality woody nut and edible oil tree with a planting area of about 5,000,000 hectare in China. Walnut anthracnose is a serious disease, infecting approximately 50% of the fruits and causing a great yield losses (Wang et al. 2016). In 2019 to 2020, walnut fruits with anthracnose symptoms were collected from walnut orchards in province of Hubei, Sichuan procinve and Chongqing municipality, China. Symptoms on fruits were circular or subcircular or irregular shaped, with brown to black water soaked and sunken lesions. The black lesions enlarged and amalgamated into large necrotic areas. The older spots in the center became blackish with acervuli causing the complete mummification of the fruit, and orange conidial masses appeared under wet conditions. Necrotic tissues of the fruits were sterilized in 75% ethanol solution for 30 s, then sterilized in 4% sodium hypochlorite for 1min, and washed 3 times with sterile distilled water. The tissues were put on potato dextrose agar (PDA) and incubated at 25℃. Pure cultures were obtained by single-spore culturing method and the isolate HBBK4-4 was deposited into the China's Forestry Culture Collection Center (CFCC 57388). On PDA, the colonies were cottony, white to pale gray with aerial mycelium on the upper side and pink with black spots on the reverse. The mycelial growth rate was 9.6 mm/day at 25°C. Conidia were 1-celled, colorless, smooth-walled, straight, cylindrical to cylindrical-clavate with acute ends, 12.5 to 18.2 × 3.9 to 5.4 µm (mean 15.3 ± 3.7 × 4.9 ± 0.6 µm, n = 40). Most conidia germinated and developed one pleurogenous, 1-celled appressorium. Appressoria were single, medium brown, smooth-walled, ovate to ellipsoid, 5.4 to 7.8 × 5.4 to 7.8 µm (mean 6.7 ± 0.6 × 6.3 ± 0.5 µm, n = 30). These morphological characteristics were in concordance with published descriptions of Collectotrichum acutatum species complex. To further confirm the identity, internal transcribed spacer (ITS), beta-tubulin (TUB2), chitin synthase 1 (CHS-I) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified and sequenced (Damm et al. 2012). The ITS (OM189549) and TUB2 (OM273642) sequences of isolate HBBK4-4 showed 100% similarity, and GAPDH (OM249791) and CHS-1 (OM273641) sequences showed 98.7% and 99.6% similarity with C. nymphaeae CBS100064 respectively. A maximum likelihood phylogenetic tree was generated based on combining all sequenced loci in MEGA5. 18 isolates including HBBK4-4 fell in the C. nymphaeae clade with 96% bootstrap support. To verify Koch's postulates, six isolates were used for pathogenicity test, and 20 healthy fruits and 15 fully expanded leaves for each isolate were inoculated with 5-mm-diameter mycelial plugs. Controls consisted of detached premature fruits inoculated with a PDA plug without the fungus. Six days after inoculation, all fruits and leaves developed anthracnose symptoms similar to those observed in the field, while the controls remained healthy. The pathogenicity tests were repeated twice with the same results. The morphology of the reisolated fungi was consistent with the inoculated one, fulfilling Koch's postulates. The isolate HBBK4-4 was identified as C. nymphaeae, based on the description by Damm et al. (2012). The species C. nymphaeae has been previously reported to cause severe anthracnose on walnut in France (Da Lio et al., 2018), Brazil (Savian et al., 2019) and Italy (Luongo et al., 2022). To our knowledge, this is the first report of C. nymphaeae as a pathogen of walnut anthracnose in China. The result provided crucial information for epidemiologic studies and management of this disease.

15.
Mikrochim Acta ; 189(9): 360, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042107

RESUMO

A spherical chiral porous organic polymer (POPs) COP-1 is synthesized by the Friedel-Crafts alkylation reaction of Boc-3-(4-biphenyl)-L-alanine (BBLA) and 4,4'-bis(chloromethyl)-1,1'-biphenyl (BCMBP), which was used as a novel chiral stationary phase (CSPs) for mixed-mode high-performance liquid chromatography (HPLC) enantioseparation. The racemic compounds were resolved in normal-phase liquid chromatography (NPLC) using n-hexane/isopropanol as mobile phase and reversed-phase liquid chromatography (RPLC) using methanol/water as mobile phase. The COP-1-packed column exhibited excellent separation performance toward various racemic compounds including alcohols, amines, ketones, esters, epoxy compounds, organic acids, and amino acids in NPLC and RPLC modes. The effects of analyte mass and column temperature on the separation efficiency of racemic compounds were investigated. In addition, the chiral resolution ability of the COP-1-packed column not only can be complementary in RPLC/NPLC modes but also exhibit a good chiral recognition complementarity with Chiralpak AD-H column and chiral porous organic cage (POC) NC1-R column. The relative standard deviations (RSD) (n = 5) of the retention time, resolution value, and peak area by repeated separation of 1-(4-chiorophenyl)ethanol are all below 3.0%. The COP-1 column shows high column efficiency (e.g., 17,320 plates m-1 for 1-(4-chlorophenyl)ethanol on COP-1 column in NPLC), high enantioselectivity, and good reproducibility toward various racemates. This work demonstrates that chiral POPs microspheres are promising chiral materials for HPLC enantioseparation.


Assuntos
Aminas , Polímeros , Cromatografia Líquida de Alta Pressão/métodos , Etanol , Porosidade , Reprodutibilidade dos Testes , Estereoisomerismo
16.
J Allergy Clin Immunol ; 148(3): 783-789, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33744327

RESUMO

BACKGROUND: The Janus kinase (JAK) pathway mediates the activity of many asthma-relevant cytokines, including IL-4 and IL-13. GDC-0214 is a potent, inhaled, small-molecule JAK inhibitor being developed for the treatment of asthma. OBJECTIVE: We sought to determine whether GDC-0214 reduces fractional exhaled nitric oxide (Feno), a JAK1-dependent biomarker of airway inflammation, in patients with mild asthma. METHODS: We conducted a double-blind, randomized, placebo-controlled, phase 1 proof-of-activity study in adults with mild asthma and Feno higher than 40 parts per billion (ppb). Subjects were randomized 2:1 (GDC-0214:placebo) into 4 sequential ascending-dose cohorts (1 mg once daily [QD], 4 mg QD, 15 mg QD, or 15 mg twice daily). All subjects received 4 days of blinded placebo, then 10 days of either active drug or placebo. The primary outcome was placebo-corrected percent reduction in Feno from baseline to day 14. Baseline was defined as the average Feno during the blinded placebo period. Pharmacokinetics, safety, and tolerability were also assessed. RESULTS: Thirty-six subjects (mean age, 28 years; 54% females) were enrolled. Mean Feno at baseline across all subjects was 93 ± 43 ppb. At day 14, placebo-corrected difference in Feno was -23% (95% CI, -37.3 to -9) for 15 mg QD and -42% (95% CI, -57 to -27.4) for 15 mg twice daily. Higher plasma exposure was associated with greater Feno reduction. No dose-limiting adverse events, serious adverse events, or treatment discontinuations occurred. There were no major imbalances in adverse events or laboratory findings, or evidence of systemic JAK inhibition. CONCLUSIONS: GDC-0214, an inhaled JAK inhibitor, caused dose-dependent reductions in Feno in mild asthma and was well tolerated without evidence of systemic toxicity.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Inibidores de Janus Quinases/uso terapêutico , Óxido Nítrico/metabolismo , Adolescente , Adulto , Antiasmáticos/sangue , Antiasmáticos/farmacocinética , Antiasmáticos/farmacologia , Asma/metabolismo , Método Duplo-Cego , Expiração , Feminino , Humanos , Inibidores de Janus Quinases/sangue , Inibidores de Janus Quinases/farmacocinética , Inibidores de Janus Quinases/farmacologia , Masculino , Adulto Jovem
17.
Molecules ; 28(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36615496

RESUMO

Plants containing podophyllotoxin and its analogues have been used as folk medicines for centuries. The characteristic chemical structures and strong biological activities of this class of compounds attracted attention worldwide. Currently, more than ninety natural podophyllotoxins were isolated, and structure modifications of these molecules were performed to afford a variety of derivatives, which offered optimized anti-tumor activity. This review summarized up to date reports on natural occurring podophyllotoxins and their sources, structural modification and biological activities. Special attention was paid to both structural modification and optimized antitumor activity. It was noteworthy that etoposide, a derivative of podophyllotoxin, could prevent cytokine storm caused by the recent SARS-CoV-2 viral infection.


Assuntos
Antineoplásicos Fitogênicos , COVID-19 , Humanos , Podofilotoxina/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Relação Estrutura-Atividade , SARS-CoV-2
18.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(2): 176-181, 2022 Feb 15.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35209983

RESUMO

OBJECTIVES: To study the changes in the distribution and drug resistance profiles of pathogens causing bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia. METHODS: The medical data were collected from the children with acute lymphoblastic leukemia who were admitted to the First Affiliated Hospital of Zhengzhou University between January 2015 and December 2020 and developed bloodstream infection after chemotherapy. The samples were divided into the first three years group and the next three years group according to the time of testing to investigate the differences in the distribution and drug resistance profiles of pathogens as time. RESULTS: A total of 235 strains of pathogens were isolated, among which there were 159 Gram-negative strains (67.7%; mainly Escherichia coli and Klebsiella pneumoniae), 61 Gram-positive strains (26.0%; mainly Staphylococcus epidermidis), and 15 strains of fungi (6.4%; mainly Candida albicans). There were no significant differences between the first three years group and the next three years group in the detection rate of Gram-negative bacteria (68.8% vs 66.9%, P>0.05) or Gram-positive bacteria (29.2% vs 23.7%, P>0.05). Compared with the first three years group, the next three years group had significant increases in the detection rate of Streptococcus mitis (5.8% vs 0.0%, P<0.05) and fungi (9.4% vs 2.1%, P<0.05). There was no significant difference in the drug resistance rate of Gram-negative or Gram-positive bacteria between the two groups (P>0.05). CONCLUSIONS: Enterobacteriaceae bacteria are the main pathogens of bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia, while the detection rates of Streptococcus mitis and fungi tend to increase as time, which needs to be taken seriously in clinical practice.


Assuntos
Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Sepse , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Criança , Farmacorresistência Bacteriana , Bactérias Gram-Negativas , Humanos , Testes de Sensibilidade Microbiana , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estudos Retrospectivos , Sepse/tratamento farmacológico
19.
Mol Psychiatry ; 25(3): 603-613, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-29915376

RESUMO

Presenilin-1 (PSEN1) is the catalytic subunit of the γ-secretase complex, and pathogenic mutations in the PSEN1 gene account for the majority cases of familial AD (FAD). FAD-associated mutant PSEN1 proteins have been shown to affect APP processing and Aß generation and inhibit Notch1 cleavage and Notch signaling. In this report, we found that a PSEN1 mutation (S169del) altered APP processing and Aß generation, and promoted neuritic plaque formation as well as learning and memory deficits in AD model mice. However, this mutation did not affect Notch1 cleavage and Notch signaling in vitro and in vivo. Taken together, we demonstrated that PSEN1S169del has distinct effects on APP processing and Notch1 cleavage, suggesting that Notch signaling may not be critical for AD pathogenesis and serine169 could be a critical site as a potential target for the development of novel γ-secretase modulators without affecting Notch1 cleavage to treat AD.


Assuntos
Doença de Alzheimer/genética , Presenilina-1/genética , Presenilina-1/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Receptores Notch/metabolismo , Receptores Notch/fisiologia , Transdução de Sinais/genética
20.
J Org Chem ; 86(12): 8027-8035, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34105963

RESUMO

Polymeric nanoreactors in water fabricated by the self-assembly of amphiphilic copolymers have attracted much attention due to their good catalytic performance without using organic solvents. However, the disassembly and instability of relevant nanostructures often compromise their potential applicability. Herein, the preparation of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-containing nanoreactors by the self-assembly of amphiphilic bottlebrush copolymers has been demonstrated. First, a macromonomer having a norbornenyl polymerizable group was prepared by RAFT polymerization of hydrophobic and hydrophilic monomers. The macromonomer was further subjected to ring-opening metathesis polymerization to produce an amphiphilic bottlebrush copolymer. Further, TEMPO, as a catalyst, was introduced into the hydrophobic block through the activated ester strategy. Finally, TEMPO-functionalized polymeric nanoreactors were successfully obtained by self-assembly in water. The nanoreactors exhibited excellent catalytic activities in selective oxidation of alcohols in water. More importantly, the reaction kinetics showed that the turnover frequency is greatly increased compared to that of the similar nanoreactor prepared from liner copolymers under the same conditions. The outstanding catalytic activities of the nanoreactors from bottlebrush copolymers could be attributed to the more stable micellar structure using the substrate concentration effect. This work presents a new strategy to fabricate stable nanoreactors, paving the way for highly efficient organic reactions in aqueous solutions.

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