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1.
J Am Chem Soc ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847614

RESUMO

Axially chiral biaryls featuring a C-N axis are important functional molecules in diverse fields. The asymmetric Buchwald-Hartwig reaction represents a powerful strategy for these targets. Previous studies, however, have been predominantly restricted to intramolecular atroposelective coupling, likely due to the steric and entropic effects in the reductive elimination of Pd(II) species with sterically congested aryl and nitrogen groups. We now report two intermolecular Buchwald-Hartwig coupling systems of bulky NH lactams and halohydrocarbons enabled by rerouting the mechanism of C-N reductive elimination to one that accommodates sterically challenging substrates. Both atroposelective coupling systems exhibited functional group tolerance, excellent enantioselectivity, and high Z selectivity (if applicable), affording C-N atropisomeric biaryl and olefins through de novo construction of a C-N chiral axis. Experimental and computational studies were performed to elucidate the mechanism, and the switch of the reaction pathways is traced to the steric effect (ortho substituent) of the aryl halide substrate. A bulky 2,6-disubstituted aryl halide reorients the proximal lactamide ligand to its unusual O-ligation mode. With the amide oxygen participation, this intermediate undergoes C-N reductive elimination with an accessible barrier through a five-membered ring transition state, a pathway as well as a chiral induction mode that has been much underexplored in asymmetric catalysis.

2.
Technol Health Care ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848202

RESUMO

BACKGROUND: Obstructive sleep apnea (OSA) is a common sleep disordered breathing disorder, which can cause serious damage to multiple human systems. Although polysomnography (PSG) is the current gold standard for diagnosis, it is complex and expensive. Therefore, it is of great significance to find a simple, economical and rapid primary screening and diagnosis method to replace PSG for the diagnosis of OSA. OBJECTIVE: The purpose of this study is to propose a new method for the diagnosis and classification of OSA, which is used to automatically detect the duration of sleep apnea hypopnea events (AHE), so as to estimate the ratio(S) of the total duration of all-night AHE to the total sleep time only based on the sound signal of sleep respiration, and to identify OSA. METHODS: We performed PSG tests on participants and extracted relevant sleep breathing sound signal data. This study is carried out in two stages. In the first stage, the relevant PSG report data of eligible subjects were recorded, the total duration of AHE in each subject's data was extracted, and the S value was calculated to evaluate the severity of OSA. In the second stage, only the sleep breath sound signal data of the same batch of subjects were used for automatic detection, and the S value in the sleep breath sound signal was extracted, and the S value was compared with the PSG diagnosis results to calculate the accuracy of the experimental method. RESULTS: Among 225 subjects. Using PSG as the reference standard, the S value extracted from the PSG diagnostic data report can accurately diagnose OSA(accuracy rate 99.56%) and distinguish its severity (accuracy rate 95.11%). The accuracy of the S value detected in the sleep breathing sound signal in the diagnosis of severe OSA reached 100%. CONCLUSION: The results show that the experimental parameter S value is feasible in OSA diagnosis and classification. OSA can be identified and evaluated only by sleep breathing sounds. This method helps to simplify the diagnostic grading of traditional OSA and lays a foundation for the subsequent development of simple diagnostic grading equipment.

3.
Medicine (Baltimore) ; 103(24): e38539, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875396

RESUMO

Orexin in cerebrospinal fluid (CSF) is a neuropeptide synthesized by a cluster of neurons in the lateral hypothalamus. It mainly functions to maintain arousal, regulate feeding, and participate in reward mechanisms. Radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) can detect CSF orexin. At present, RIA is widely used but is limited by various conditions, which is not conducive to its widespread development. We aimed to determine whether ELISA can replace RIA in detecting orexin in CSF. We investigated the results of 20 patients with central disorders of hypersomnolence, including 11 with narcolepsy type 1, 2 with narcolepsy type 2, 5 with idiopathic hypersomnia, and 2 with other causes of somnolence. RIA and ELISA were used to detect CSF orexin, and P values <.05 were considered to be significant. In the narcolepsy and non-narcolepsy type 1 groups, there was no correlation between the RIA and ELISA results (P > .05). In the narcolepsy type 1 group, the ELISA and RIA results were significantly different (P < .05), but this was not observed in the non-narcolepsy type 1 group (P > .05). The accuracy of ELISA to detect CSF orexin was lower than that of RIA (P < .05). ELISA cannot replace RIA in the measurement of CSF orexin, and RIA is recommended as the first choice when narcolepsy is suspected.


Assuntos
Ensaio de Imunoadsorção Enzimática , Narcolepsia , Orexinas , Radioimunoensaio , Humanos , Orexinas/líquido cefalorraquidiano , Narcolepsia/líquido cefalorraquidiano , Narcolepsia/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Masculino , Radioimunoensaio/métodos , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente
4.
Curr Med Sci ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789818

RESUMO

OBJECTIVE: Diabetic foot ulcer (DFU) is one of the most serious complications of diabetes. Leukocyte- and platelet-rich fibrin (L-PRF) is a second-generation autologous platelet-rich plasma. This study aims to investigate the clinical effects of L-PRF in patients with diabetes in real clinical practice. METHODS: Patients with DFU who received L-PRF treatment and standard of care (SOC) from 2018 to 2019 in Tongji Hospital were enrolled. The clinical information including patient characteristics, wound evaluation (area, severity, infection, blood supply), SOC of DFU, and images of ulcers was retrospectively extracted and analyzed. L-PRF treatment was performed every 7±2 days until the ulcer exhibited complete epithelialization or an overall percent volume reduction (PVR) greater than 80%. Therapeutic effectiveness, including overall PVR and the overall and weekly healing rates, was evaluated. RESULTS: Totally, 26 patients with DFU were enrolled, and they had an ulcer duration of 47.0 (35.0, 72.3) days. The severity and infection of ulcers varied, as indicated by the Site, Ischemia, Neuropathy, Bacterial Infection, and Depth (SINBAD) scores of 2-6, Wagner grades of 1-4, and the Perfusion, Extent, Depth, Infection and Sensation (PEDIS) scores of 2-4. The initial ulcer volume before L-PRF treatment was 4.94 (1.50, 13.83) cm3, and the final ulcer volume was 0.35 (0.03, 1.76) cm3. The median number of L-PRF doses was 3 (2, 5). A total of 11 patients achieved complete epithelialization after the fifth week of treatment, and 19 patients achieved at least an 80% volume reduction after the seventh week. The overall wound-healing rate was 1.47 (0.63, 3.29) cm3/week, and the healing rate was faster in the first 2 weeks than in the remaining weeks. Concurrent treatment did not change the percentage of complete epithelialization or healing rate. CONCLUSION: Adding L-PRF to SOC significantly improved wound healing in patients with DFU independent of the ankle brachial index, SINBAD score, or Wagner grade, indicating that this method is appropriate for DFU treatment under different clinical conditions.

5.
J Mol Med (Berl) ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814362

RESUMO

Extracellular vesicles (EVs) are important carriers of signaling molecules, such as nucleic acids, proteins, and lipids, and have become a focus of increasing interest due to their numerous physiological and pathological functions. For a long time, most studies on EV components focused on noncoding RNAs; however, in recent years, extracellular vesicle proteins (EVPs) have been found to play important roles in diagnosis, treatment, and drug resistance and thus have been considered favorable biomarkers and therapeutic targets for various tumors. In this review, we describe the general protocols of research on EVPs and summarize their multifaceted roles in precision medicine applications, including cancer diagnosis, dynamic monitoring of therapeutic efficacy, drug resistance research, tumor microenvironment interaction research, and anticancer drug delivery.

6.
Sci Adv ; 10(19): eado4489, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728391

RESUMO

Atropisomeric indoles defined by a N─N axis are an important class of heterocycles in synthetic and medicinal chemistry and material sciences. However, they remain heavily underexplored due to limited synthetic methods and challenging stereocontrol over the short N─N bonds. Here, we report highly atroposelective access to N─N axially chiral indoles via the asymmetric Larock reaction. This protocol leveraged the powerful role of chiral phosphoramidite ligand to attenuate the common ligand dissociation in the original Larock reaction, forming N─N chiral indoles with excellent functional group tolerance and high enantioselectivity via palladium-catalyzed intermolecular annulation between readily available o-iodoaniline and alkynes. The multifunctionality in the prepared chiral indoles allowed diverse post-coupling synthetic transformations, affording a broad array of functionalized chiral indoles. Experimental and computational studies have been conducted to explore the reaction mechanism, elucidating the enantio-determining and rate-limiting steps.

7.
Postgrad Med J ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652265

RESUMO

PURPOSE: Umeclidinium plus vilanterol (UMEC/VI) is an inhaled long-acting muscarinic antagonist/long-acting beta2-agonist (LAMA/LABA), recently approved as once-daily maintenance therapy for chronic obstructive pulmonary disease (COPD). This meta-analysis aims to assess the efficacy and safety of UMEC/VI compared with fluticasone propionate plus salmeterol (FP/SAL). METHODS: A systematic search was conducted by a trained medical research librarian across MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Chinese Biomedical Literature Database (CBM) for randomized controlled trials comparing UMEC/VI with FP/SAL in COPD patients. Two reviewers independently assessed the risk of bias and extracted data. The primary outcome was 0-24 h weighted mean (wm) forced expiratory volume in the first second (FEV1), trough FEV1. The secondary outcomes were other lung functions, symptoms, quality of life, and safety. RESULTS: Three studies with 2119 patients were included in the meta-analysis. UMEC/VI showed improvement in 0-24 h wm FEV1 (mean difference (MD) 0.08 L, 95% confidence interval (CI) 0.06 to 0.10, P < 0.01, moderate quality) and trough FEV1 (MD 0.09 L, 95% CI 0.07 to 0.11, P < 0.01, moderate quality) in comparison with FP/SAL. UMEC/VI statistically significantly improved all other lung functions compared with FP/SAL. However, there were no significant differences between UMEC/VI and FP/SAL in rescue-medication use, symptomatic endpoints, and health outcomes. UMEC/VI also demonstrated fewer drug-related adverse effects (risk ratio 0.47, 95% CI 0.27 to 0.82, P = 0.01, low quality). CONCLUSIONS: UMEC/VI, when compared with FP/SAL, demonstrated significant improvements in lung functions with fewer drug-related adverse effects. However, the conclusion was limited by the scarcity of studies and long-term trials.

8.
Oncoimmunology ; 13(1): 2340154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601319

RESUMO

Metabolism reprogramming within the tumor microenvironment (TME) can have a profound impact on immune cells. Identifying the association between metabolic phenotypes and immune cells in lung adenocarcinoma (LUAD) may reveal mechanisms of resistance to immune checkpoint inhibitors (ICIs). Metabolic phenotypes were classified by expression of metabolic genes. Somatic mutations and transcriptomic features were compared across the different metabolic phenotypes. The metabolic phenotype of LUAD is predominantly determined by reductase-oxidative activity and is divided into two categories: redoxhigh LUAD and redoxlow LUAD. Genetically, redoxhigh LUAD is mainly driven by mutations in KEAP1, STK11, NRF2, or SMARCA4. These mutations are more prevalent in redoxhigh LUAD (72.5%) compared to redoxlow LUAD (17.4%), whereas EGFR mutations are more common in redoxlow LUAD (19.0% vs. 0.7%). Single-cell RNA profiling of pre-treatment and post-treatment samples from patients receiving neoadjuvant chemoimmunotherapy revealed that tissue-resident memory CD8+ T cells are responders to ICIs. However, these cells are significantly reduced in redoxhigh LUAD. The redoxhigh phenotype is primarily attributed to tumor cells and is positively associated with mTORC1 signaling. LUAD with the redoxhigh phenotype demonstrates a lower response rate (39.1% vs. 70.8%, p = 0.001), shorter progression-free survival (3.3 vs. 14.6 months, p = 0.004), and overall survival (12.1 vs. 31.2 months, p = 0.022) when treated with ICIs. The redoxhigh phenotype in LUAD is predominantly driven by mutations in KEAP1, STK11, NRF2, and SMARCA4. This phenotype diminishes the number of tissue-resident memory CD8+ T cells and attenuates the efficacy of ICIs.


Assuntos
Quinases Proteína-Quinases Ativadas por AMP , Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Fator 2 Relacionado a NF-E2/genética , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Oxirredução , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Imunoterapia , Mutação , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Linfócitos T , Linfócitos T CD8-Positivos , Microambiente Tumoral/genética , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição
9.
Ecotoxicol Environ Saf ; 276: 116259, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581905

RESUMO

Gestational cadmium exposure increases the risk of preeclampsia. Placenta mitophagy was activated in preeclampsia. The aim of present study was to explore the mechanism of cadmium-induced mitophagy activation and its association with preeclampsia. Mitophagy markers expression levels were detected by quantitative real-time PCR, Western blot, immunofluorescence and immunochemistry in preeclampsia placenta. JEG3 cells were treated with CdCl2, iopanoic acid (IOP), 3-methyladenine and PGC1α SiRNA to verify mechanism of cadmium-induced mitophagy. Mitophagy marker LC3BII/I and P62 expression were increased and mitochondrial membrane receptor protein TOM20 and FUNDC1 expression were decreased in preeclampsia placenta as compared with that in normotension control. Mitophagy marker LC3BII/I and P62 expression were increased and TOM20 and FUNDC1 expression was decreased in CdCl2-treated JEG3 cells. Meanwhile, mitochondrial biogenesis regulator, PGC1α expression was decreased in preeclampsia and CdCl2-treated JEG3 cells. The expressions of LC3B and P62 were increased and the expressions of TOM20, FUNDC1 and PGC1α were decreased in IOP-treated cell. PGC1α SiRNA transfection led to increased expression of LC3BII/I and P62 and decreased expression of TOM20 and FUNDC1. The expression of sFlt1 was increased in preeclampsia placenta, CdCl2-treated cells, in IOP-treated cells and in PGC1α SiRNA transfected cells. 3-methyladenine treatment protected the increased expression of sFlt1 in CdCl2-treated cells, in IOP-treated cells and in PGC1α SiRNA transfected cells. Meanwhile, co-treatment of cadmium and IOP or PGC1αSiRNA led to a reduce expressions of OPA1, MFN1, MFN2 and FUNDC1 as compared to cadmium-treated, IOP-treated and PGC1α SiRNA-treated cells. These results elucidated that maternal cadmium exposure activated placenta mitophagy through downregulation of thyroid hormone receptor signal mediated decreased expression of PGC1α and was associated with the occurrence of preeclampsia.


Assuntos
Mitofagia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Placenta , Pré-Eclâmpsia , Receptores dos Hormônios Tireóideos , Humanos , Pré-Eclâmpsia/induzido quimicamente , Feminino , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Gravidez , Mitofagia/efeitos dos fármacos , Placenta/efeitos dos fármacos , Placenta/metabolismo , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Cádmio/toxicidade , Regulação para Baixo/efeitos dos fármacos , Adulto , Transdução de Sinais/efeitos dos fármacos
10.
Antimicrob Agents Chemother ; 68(5): e0134823, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38572960

RESUMO

Mycobacterium abscessus (M. abscessus) inherently displays resistance to most antibiotics, with the underlying drug resistance mechanisms remaining largely unexplored. Efflux pump is believed to play an important role in mediating drug resistance. The current study examined the potential of efflux pump inhibitors to reverse levofloxacin (LFX) resistance in M. abscessus. The reference strain of M. abscessus (ATCC19977) and 60 clinical isolates, including 41 M. abscessus subsp. abscessus and 19 M. abscessus subsp. massilense, were investigated. The drug sensitivity of M. abscessus against LFX alone or in conjunction with efflux pump inhibitors, including verapamil (VP), reserpine (RSP), carbonyl cyanide 3-chlorophenylhydrazone (CCCP), or dicyclohexylcarbodiimide (DCC), were determined by AlarmarBlue microplate assay. Drug-resistant regions of the gyrA and gyrB genes from the drug-resistant strains were sequenced. The transcription level of the efflux pump genes was monitored using qRT-PCR. All the tested strains were resistant to LFX. The drug-resistant regions from the gyrA and gyrB genes showed no mutation associated with LFX resistance. CCCP, DCC, VP, and RSP increased the susceptibility of 93.3% (56/60), 91.7% (55/60), 85% (51/60), and 83.3% (50/60) isolates to LFX by 2 to 32-fold, respectively. Elevated transcription of seven efflux pump genes was observed in isolates with a high reduction in LFX MIC values in the presence of efflux pump inhibitors. Efflux pump inhibitors can improve the antibacterial activity of LFX against M. abscessus in vitro. The overexpression of efflux-related genes in LFX-resistant isolates suggests that efflux pumps are associated with the development of LFX resistance in M. abscessus.


Assuntos
Antibacterianos , Levofloxacino , Testes de Sensibilidade Microbiana , Mycobacterium abscessus , Reserpina , Levofloxacino/farmacologia , Antibacterianos/farmacologia , Mycobacterium abscessus/efeitos dos fármacos , Mycobacterium abscessus/genética , Reserpina/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , DNA Girase/genética , DNA Girase/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Farmacorresistência Bacteriana/genética , Humanos , Verapamil/farmacologia
11.
J Glob Antimicrob Resist ; 37: 135-140, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38561143

RESUMO

OBJECTIVE: This study aims to estimate the overall in vitro activity of bedaquiline (BDQ) against clinical isolates of Mycobacterium abscessus complex (MABS) and M. avium complex (MAC), considering BDQ as a repurposed drug for non-tuberculous mycobacteria (NTM) infections. METHODS: We conducted a systematic review of publications in PubMed/ MEDLINE, Web of Science, and Embase up to 15 April 2023. Studies were included if they followed the Clinical and Laboratory Standards Institute (CLSI) criteria for drug susceptibility testing (DST). Using a random effects model, we assessed the overall in vitro BDQ resistance rate in clinical isolates of MABS and MAC. Sources of heterogeneity were analysed using Cochran's Q and the I2 statistic. All analyses were performed using CMA V3.0. RESULTS: A total of 24 publications (19 reports for MABS and 11 for MAC) were included. Using 1 µg/mL and 2 µg/mL as the breakpoint for BDQ resistance, the pooled rates of in vitro BDQ resistance in clinical isolates of MABS were found to be 1.8% (95% confidence interval [CI], 0.7-4.6%) and 1.7% (95% CI, 0.6-4.4%), respectively. In the case of MAC, the pooled rates were 1.7% (95% CI, 0.4-6.9%) and 1.6% (95% CI, 0.4-6.8%) for 1 µg/mL and 2 µg/mL, respectively. CONCLUSION: This study reports the prevalence of BDQ resistance in clinical isolates of MABS and MAC. The findings suggest that BDQ holds potential as a repurposed drug for treating MABS and MAC infections.

12.
J Infect ; 88(5): 106149, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574774

RESUMO

BACKGROUND: Distinguishing between nontuberculous mycobacterial (NTM) lung infections and pulmonary tuberculosis becomes challenging due to their similar clinical manifestations and radiological images. Consequently, instances of delayed diagnosis or misdiagnosis are highly frequent. A feasible and reliable indicator of the existence of NTM in the early stages of the disease would help to solve this dilemma. METHODS: In this study, we evaluated the potential of smear-positive and Xpert assay (Cepheid, USA) negative outcomes as an early indicator of possible NTM infection in a high TB-burden setting retrospectively and prospectively. RESULTS: During the study period, 12·77% (138/1081) of the smear-positive cases yielded negative outcomes with the simultaneous Xpert assay. From the 110 patients who yielded smear-positive/Xpert-negative outcomes and cultivated strain as well, 105 (95·45%) were proved to have NTM isolated. By incorporating an additional criterion of a negative result from the Interferon-gamma release assay, the accuracy of the screening method reached 100%. Regarding the NTM presence prediction value, smear-positive/Xpert-negative has a sensitivity of 24·86% (45/181) in all NTM isolated cases but 93·75-96·55% accuracy in retrospective study or 93·75% accuracy in prospective study in smear-positive NTM isolated cases. In addition, the specificity was ∼99·47% (943/948) in smear-positive tuberculosis cases. CONCLUSION: The clue of the presence of NTM could be obtained on the first day of the hospital visit due to the point of care (POC) feature of smear testing and Xpert assay. About one-fourth of the NTM-isolated patients would benefit from this rapid, convenient, and reliable screening strategy in the given circumstance. Smear-positive/Xpert-negative outcome is an early, trustable indicator that is indicative of NTM isolation.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Micobactérias não Tuberculosas , Sensibilidade e Especificidade , Humanos , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Masculino , Feminino , Estudos Retrospectivos , Micobactérias não Tuberculosas/isolamento & purificação , Micobactérias não Tuberculosas/genética , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Adulto , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Escarro/microbiologia , Testes de Liberação de Interferon-gama/métodos , Diagnóstico Diferencial , Idoso de 80 Anos ou mais
13.
Plants (Basel) ; 13(6)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38592783

RESUMO

This study aimed to determine the effects of the nitrogen (N) application period and level on the fate of fertilizer N and the contribution of N absorption and translocation to apple organ N. Two N application periods (labeled by the 15N tracer technique in spring and summer, represented by SP and SU, respectively) and three N levels (N0, MN, and HN) were used to determine the physiological indexes and aboveground, root, and soil 15N content of 4-year-old dwarf ('Red Fuji'/M9T337) and arborized ('Red Fuji'/Malus hupehensis Rehd.) apple trees. The results showed that HN led to shoot overgrowth, which was not conducive to the growth of the apple root system (root length, root tips, root surface area, and root volume) or the improvement of root activity. The contribution of soil N to apple organ N accounted for more than 50%, and the contribution of N application in summer to fruit N was higher than that in spring. Under HN treatment, the proportion of soil N absorbed by trees decreased, while that of fertilizer N increased; however, the highest proportion was still less than 50%, so apple trees were highly dependent on soil N. Under MN treatment, fertilizer N residue was similar to soil N consumption, and soil N fertility maintained a basic balance. Under HN treatment, fertilizer N residue was significantly higher than soil N consumption, indicating that excessive N application increased fertilizer N residue in the soil. Overall, the 15N utilization rate of arborized trees (17.33-22.38%) was higher than that of dwarf trees (12.89-16.91%). A total of 12.89-22.38% of fertilizer 15N was absorbed by trees, 30.37-35.41% of fertilizer 15N remained in the soil, and 44.65-54.46% of fertilizer 15N was lost. The 15N utilization rate and 15N residual rate of summer N application were higher than those of spring N application, and the 15N loss rate was lower than that of spring N application. High microbial biomass N (MBN) may be one of the reasons for the high N utilization rate and the low loss rate of N application in summer.

14.
Int J Biol Macromol ; 264(Pt 2): 130729, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460643

RESUMO

Astrocyte elevated gene-1 (AEG-1) oncogene is a notorious and evolving target in a variety of human malignancies including osteosarcoma. The RNA interference (RNAi) has been clinically proven to effectively knock down specific genes. To successfully implement RNAi in vivo, protective vectors are required not only to protect unstable siRNAs from degradation, but also to deliver siRNAs to target cells with controlled release. Here, we synthesized a Zein-poly(l-lysine) dendrons non-viral modular system that enables efficient siRNA-targeted AEG-1 gene silencing in osteosarcoma and encapsulation of antitumor drugs for controlled release. The rational design of the ZDP integrates the non-ionic and low immunogenicity of Zein and the positive charge of the poly(l-lysine) dendrons (DPLL) to encapsulate siRNA and doxorubicin (DOX) payloads via electrostatic complexes and achieve pH-controlled release in a lysosomal acidic microenvironment. Nanocomplexes-directed delivery greatly improves siRNA stability, uptake, and AEG-1 sequence-specific knockdown in 143B cells, with transfection efficiencies comparable to those of commercial lipofectamine but with lower cytotoxicity. This AEG-1-focused RNAi therapy supplemented with chemotherapy inhibited, and was effective in inhibiting the growth in of osteosarcoma xenografts mouse models. The combination therapy is an alternative or combinatorial strategy that can produce durable inhibitory responses in osteosarcoma patients.


Assuntos
Neoplasias Ósseas , Dendrímeros , Nanopartículas , Osteossarcoma , Zeína , Animais , Camundongos , Humanos , Polilisina , Azidas , Preparações de Ação Retardada , Alcinos , Doxorrubicina/farmacologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , RNA Interferente Pequeno/metabolismo , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Microambiente Tumoral
15.
BMJ ; 384: e078581, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443074

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy and safety of using magnetically guided capsule endoscopy with a detachable string (ds-MCE) for detecting and grading oesophagogastric varices in adults with cirrhosis. DESIGN: Prospective multicentre diagnostic accuracy study. SETTING: 14 medical centres in China. PARTICIPANTS: 607 adults (>18 years) with cirrhosis recruited between 7 January 2021 and 25 August 2022. Participants underwent ds-MCE (index test), followed by oesophagogastroduodenoscopy (OGD, reference test) within 48 hours. The participants were divided into development and validation cohorts in a ratio of 2:1. MAIN OUTCOME MEASURES: The primary outcomes were the sensitivity and specificity of ds-MCE in detecting oesophagogastric varices compared with OGD. Secondary outcomes included the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices and the diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices. RESULTS: ds-MCE and OGD examinations were completed in 582 (95.9%) of the 607 participants. Using OGD as the reference standard, ds-MCE had a sensitivity of 97.5% (95% confidence interval 95.5% to 98.7%) and specificity of 97.8% (94.4% to 99.1%) for detecting oesophagogastric varices (both P<0.001 compared with a prespecified 85% threshold). When using the optimal 18% threshold for luminal circumference of the oesophagus derived from the development cohort (n=393), the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices in the validation cohort (n=189) were 95.8% (89.7% to 98.4%) and 94.7% (88.2% to 97.7%), respectively. The diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices was 96.3% (92.6% to 98.2%), 96.9% (95.2% to 98.0%), and 96.7% (95.0% to 97.9%), respectively. Two serious adverse events occurred with OGD but none with ds-MCE. CONCLUSION: The findings of this study suggest that ds-MCE is a highly accurate and safe diagnostic tool for detecting and grading oesophagogastric varices and is a promising alternative to OGD for screening and surveillance of oesophagogastric varices in patients with cirrhosis. TRIAL REGISTRATION: ClinicalTrials.gov NCT03748563.


Assuntos
Endoscopia por Cápsula , Varizes Esofágicas e Gástricas , Varizes , Adulto , Humanos , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Cirrose Hepática/complicações , Estudos Prospectivos
16.
J Int Med Res ; 52(3): 3000605241232520, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38530023

RESUMO

Androgen insensitivity syndrome (AIS) is a rare disorder with X-linked recessive inheritance in 46 XY patients. The clinical manifestations vary between patients, especially regarding external genitalia development. Herein, the case of AIS in a 13-year-old male, who was born with hypospadias and presented to the hospital with gynaecomastia that had developed from 8 years of age, is reported. No micropenis, cryptorchidism or bifid scrotum were found. Testis volume was 12 ml on both sides. His testosterone and luteinizing hormone levels were normal compared with sex- and age-adjusted reference range. His bone age was approximately 13 years according to Greulich-Pyle assessment. Sequence analysis of the androgen receptor (AR) gene revealed a mutation (c.2041A>G) in exon 4, a novel mutation site in the AR gene. Prediction analysis suggested this to be a disease-causing variant. A milder clinical presentation and normal hormone levels in cases of partial AIS might differ from the usually reported signs and symptoms. A diagnosis of AIS should not be ignored in teenage patients who present with gynaecomastia and hypospadias, but normal hormone levels.


Assuntos
Síndrome de Resistência a Andrógenos , Ginecomastia , Hipospadia , Masculino , Adolescente , Humanos , Síndrome de Resistência a Andrógenos/diagnóstico , Síndrome de Resistência a Andrógenos/genética , Ginecomastia/diagnóstico , Ginecomastia/genética , Receptores Androgênicos/genética , Hipospadia/diagnóstico , Hipospadia/genética , Mutação , Testosterona
17.
J Pineal Res ; 76(2): e12948, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38488331

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic (DA) neurons and aggregation of α-synuclein (α-syn). Ferroptosis, a form of cell death induced by iron accumulation and lipid peroxidation, is involved in the pathogenesis of PD. It is unknown whether melatonin receptor 1 (MT1) modulates α-syn and ferroptosis in PD. Here, we used α-syn preformed fibrils (PFFs) to induce PD models in vivo and in vitro. In PD mice, α-syn aggregation led to increased iron deposition and ferroptosis. MT1 knockout exacerbated these changes and resulted in more DA neuronal loss and severe motor impairment. MT1 knockout also suppressed the Sirt1/Nrf2/Ho1/Gpx4 pathway, reducing resistance to ferroptosis, and inhibited expression of ferritin Fth1, leading to more release of ferrous ions. In vitro experiments confirmed these findings. Knockdown of MT1 enhanced α-syn PFF-induced intracellular α-syn aggregation and suppressed expression of the Sirt1/Nrf2/Ho1/Gpx4 pathway and Fth1 protein, thereby aggravating ferroptosis. Conversely, overexpression of MT1 reversed these effects. Our findings reveal a novel mechanism by which MT1 activation prevents α-syn-induced ferroptosis in PD, highlighting the neuroprotective role of MT1 in PD.


Assuntos
Ferroptose , Melatonina , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , alfa-Sinucleína/metabolismo , alfa-Sinucleína/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Melatonina/farmacologia , Receptor MT1 de Melatonina/metabolismo , Sirtuína 1/metabolismo , Neurônios Dopaminérgicos , Ferro/metabolismo
18.
J Org Chem ; 89(6): 3926-3930, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38441005

RESUMO

2- or 4-Pyridyl benzylic amines represent a privileged motif in drug discovery. However, the formation of heterocyclic benzylic amines with fully substituted α-carbons can require the execution of lengthy synthetic routes, which limit their application. Addition of various nucleophilic agents to Ellman's imines has been well established; however, there is no precedented literature reported for pyridyl-type nucleophiles, which are very important for medicinal chemistry. In this letter, we disclose the development of a one-step synthesis of heterocyclic benzylic amines with fully substituted α-carbons from heteroaryl halides and sulfinyl imines. Starting from 2,4-dibromopyridine, regioselective synthesis of 2- or 4-pyridyl benzylic amines could be achieved by choosing toluene or MTBE as a solvent.

19.
Open Life Sci ; 19(1): 20220834, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38465343

RESUMO

Parkinson's disease (PD) is a ubiquitous brain cell degeneration disease and presents a significant therapeutic challenge. By injecting 6-hydroxydopamine (6-OHDA) into the left medial forebrain bundle, rats were made to exhibit PD-like symptoms and treated by intranasal administration of a low-dose (2 × 105) or high-dose (1 × 106) human neural stem cells (hNSCs). Apomorphine-induced rotation test, stepping test, and open field test were implemented to evaluate the motor behavior and high-performance liquid chromatography was carried out to detect dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), serotonin, and 5-hydroxyindole-3-acetic acid in the striatum of rats. Animals injected with 6-OHDA showed significant motor function deficits and damaged dopaminergic system compared to the control group, which can be restored by hNSCs treatment. Treatment with hNSCs significantly increased the tyrosine hydroxylase-immunoreactive cell count in the substantia nigra of PD animals. Moreover, the levels of neurotransmitters exhibited a significant decline in the striatum tissue of animals injected with 6-OHDA when compared to that of the control group. However, transplantation of hNSCs significantly elevated the concentration of DA and DOPAC in the injured side of the striatum. Our study offered experimental evidence to support prospects of hNSCs for clinical application as a cell-based therapy for PD.

20.
Curr Neurovasc Res ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38468527

RESUMO

AIMS: We evaluated endogenous melatonin levels in the acute phase of cerebral infarction and explored the impact of possible changes in melatonin levels on the prognosis of patients. METHODS: This study recruited acute ischemic stroke (AIS) patients from the Department of the Second Affiliated Hospital of Soochow University between December 2019 and June 2021, along with healthy control subjects. Salivary melatonin samples were collected from each participant between 7 pm and 10 pm, and fasting plasma was collected the following morning to measure the levels of inflammatory markers. The prognosis was assessed through follow-up three months after discharge. The relationship between melatonin levels and plasma inflammatory markers was assessed, followed by an analysis of the effect of melatonin levels on patient prognosis. RESULTS: The study enrolled a total of 160 participants, including 120 AIS patients aged 50 years or older (61.7% male) and 40 age-matched controls (55.0% male). The AIS group exhibited lower salivary melatonin levels at 19 (P = 0.002), 20 (P < 0.001), 21 (P < 0.001), and 22 (P < 0.001) o'clock, and the average melatonin level was also lower (P < 0.001). Logistic regression analysis models indicated an association between low melatonin levels and poor prognosis. Salivary melatonin levels demonstrated good predictive ability for the prognosis of AIS patients. CONCLUSION: Melatonin levels were lower in AIS patients compared to controls. In addition, lower melatonin levels were associated with a poorer prognosis among AIS patients.

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