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1.
J Am Chem Soc ; 146(36): 24782-24787, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39207015

RESUMEN

The first type II intramolecular [3 + 2] annulation of allenylsilane-ene has been achieved, enabling diastereoselective and efficient construction of synthetically challenging bridged five-membered ring systems such as bicyclo[3.2.1]. This mild and direct process shows a broad substrate scope and is highly stereospecific. Particularly, this work represents the first stereoselective method for the direct synthesis of bicyclo[3.2.1] ring systems from acyclic precursors. Additionally, the first asymmetric total syntheses of (+)- and (-)-strepsesquitriol, and the efficient formation of the synthetically challenging tetracyclic core of pierisjaponol D are achieved by this type II [3 + 2] annulation reaction.

2.
Medicine (Baltimore) ; 103(9): e37200, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38428848

RESUMEN

RATIONALE: This article presents the case of a patient with recurrent chronic diarrhea and cachexia who was misdiagnosed, followed by a literature review to summarize the reasons for misdiagnosis of POEMS syndrome and the treatment strategies. PATIENT CONCERNS: The diagnosis and treatment of this patient suggest that with the improvement of M-protein detection levels, the diagnosis of patients with low M-protein levels, such as those with POEMS syndrome, has been greatly aided. DIAGNOSES: POEMS syndrome requires polyneuropathy and monoclonal plasma cell proliferation as mandatory diagnostic criteria. Therefore, patients presenting with polyneuropathy should routinely undergo M-protein testing and consider the possibility of POEMS syndrome. INTERVENTIONS: The patient, in this case, was treated primarily with relatively conservative immunomodulatory agents. OUTCOMES: During follow-up after treatment, the patient's diarrhea and malnutrition showed significant improvement. LESSONS SUBSECTIONS: POEMS syndrome has low clinical specificity and a high rate of misdiagnosis. However, once a definitive diagnosis is made, the treatment outcome is favorable.


Asunto(s)
Síndrome POEMS , Humanos , Síndrome POEMS/complicaciones , Síndrome POEMS/diagnóstico , Resultado del Tratamiento , Errores Diagnósticos , Diarrea/complicaciones
3.
J Radiat Res ; 65(1): 47-54, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-37948449

RESUMEN

The aim of the present work was to examine the effect of polyethylene glycol (PEG)-coated superparamagnetic iron oxide (SPIO) nanoparticles carrying Pik3cb short hairpin RNA (shRNA) in the prevention of restenosis with the aid of ultrasound and a magnetic field. SPIO is a type of contrast agent used in medical imaging to enhance the visibility of specific tissues or organs. It consists of tiny iron oxide nanoparticles that can be targeted to specific areas of interest in the body. PEG-coated SPIO nanoparticles carrying Pik3cb shRNA (SPIO-shPik3cb) were prepared, and the particle size and zeta potential of PEG-coated SPIO nanoparticles with and without Pik3cb shRNA were examined. After a right common artery balloon-injured rat model was established, the rats were randomly divided into four groups, and the injured arteries were transfected with SPIO-shPik3cb, saline, SPIO-shcontrol and naked shRNA Pik3cb. During the treatment, each group was placed under a magnetic field and was transfected with the aid of ultrasound. Rats were sacrificed, and the tissue was harvested for analysis after 14 days. The results suggested that the mean particle size and zeta potential of SPIO-shPik3cbs were 151.45 ± 11 nm and 10 mV, respectively. SPIO-shPik3cb showed higher transfection efficiency and significantly inhibited the intimal thickening compared with naked Pik3cb shRNA in vascular smooth muscle cells (VSMCs) (*P < 0.05). Moreover, SPIO-shPik3cb could also significantly downregulate the expression of pAkt protein compared with naked Pik3cb shRNA. According to the results, SPIO-shPik3cb can remarkably inhibit the intimal thickening under a combination of magnetic field exposure and ultrasound.


Asunto(s)
Reestenosis Coronaria , Compuestos Férricos , Nanopartículas de Magnetita , Ratas , Animales , ARN Interferente Pequeño/genética , Imagen por Resonancia Magnética/métodos
4.
Int J Mol Med ; 52(6)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37888754

RESUMEN

Allergic rhinitis (AR) is a common pathological condition in otorhinolaryngology. Its prevalence has been increasing worldwide and is becoming a major burden to the world population. Dendritic cells (DCs) are typically activated and matured after capturing, phagocytosing, and processing allergens during the immunopathogenesis of AR. In addition, the process of DC activation and maturation is accompanied by the production of exosomes, which are cell­derived extracellular vesicles (EVs) that can carry proteins, lipids, nucleic acids, and other cargoes involved in intercellular communication and material transfer. In particular, DC­derived exosomes (Dex) can participate in allergic immune responses, where the biological substances carried by them can have potentially important implications for both the pathogenesis and treatment of AR. Dex can also be exploited to carry anti­allergy agents to effectively treat AR. This provides a novel method to explore the pathogenesis of and treatment strategies for AR further. Therefore, the present review focuses on the origin, composition, function, and biological characteristics of DCs, exosomes, and Dex, in addition to the possible relationship between Dex and AR.


Asunto(s)
Exosomas , Vesículas Extracelulares , Rinitis Alérgica , Humanos , Rinitis Alérgica/metabolismo , Alérgenos , Células Dendríticas
5.
Medicine (Baltimore) ; 102(35): e35035, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37657018

RESUMEN

To evaluate the correlation between HOXB9 expression, and the prognosis and immune infiltration in head and neck squamous cell carcinoma (HNSCC). Pan-cancer HOXB9 expression was analyzed through TIMER2.0. The HOXB9 expression data of HNSCC and normal tissues were compared using the gene expression profiling interactive analysis (GEPIA) and the cancer genome atlas (TCGA) databases. The University of Alabama at Birmingham (UALCAN) database was used to analyze the relative expression of HOXB9 in HNSCC subgroups based on clinicopathological features, including cancer stage, tumor grade and lymph node stage. Survival analysis was performed using GEPIA, TCGA-Portal, Kaplan-Meier Plotter, and UALCAN databases. The genes co-expressed with HOXB9 were identified using TCGA data, and functionally annotated by GO and KEGG analyses. Protein-protein interaction network was constructed using the STRING database and Cytoscape 3.7.1. Single-sample gene set enrichment analysis was performed to assess the correlation between HOXB9 and immune infiltration based on TCGA data. TIMER 2.0 database was used to explore the correlation between HOXB9 expression and immune infiltration multiple cancers. HOXB9 mRNA is elevated in multiple cancers, and was upregulated in HNSCC tissues compared to non-paired (P < .05 in GEPIA; P < .0001 in TCGA) as well as paired (P < .0001 in TCGA) normal tissues. In addition, HOXB9 expression was positively correlated with tumor malignancy in the GEPIA and UALCAN databases (P < .05), and negatively with patient prognosis in both databases (P < .05). High HOXB9 expression was associated with increased infiltration of aDCs, NK CD56bright cells, NK cells, and Th2 cells (P < .05), while low HOXB9 expression was associated with an increase in the proportion of DCs, iDCs, mast cells, neutrophils, and Th17 cells (P < .05). HOXB9 likely functions as an oncogene in HNSCC by disrupting the immune landscape, and is a promising prognostic biomarker and therapeutic target.


Asunto(s)
Genes Homeobox , Neoplasias de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Pronóstico , Biología Computacional , Neoplasias de Cabeza y Cuello/genética , Proteínas de Homeodominio/genética
6.
Discov Oncol ; 14(1): 171, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37707658

RESUMEN

Nasopharyngeal carcinoma (NPC) is a commonly diagnosed malignancy in southern China and southeast Asia. Previous studies have identified galactosamine-(N-acetyl)-6-sulfatase (GALNS) as a potential biomarker for multiple cancers. However, it is unknown whether GALNS plays a role in NPC development, and the underlying mechanisms remain unclear. In this study, we found that GALNS is overexpressed in NPC cell lines and tissues compared to the normal nasopharyngeal counterparts. Knocking down GALNS expression in the NPC cells significantly decreased their proliferation in vitro, and inhibited xenograft growth in a mouse model. Mechanistically, the anti-proliferative effect of GALNS silencing was the result of autophagy induction via the inhibition of PI3K-AKT-mTOR signaling pathway. Taken together, GALNS drives the progression of NPC via PI3K-AKT-mTOR signaling-mediated autophagy, and is therefore a promising therapeutic target.

7.
Quant Imaging Med Surg ; 13(8): 5022-5033, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37581060

RESUMEN

Background: The novel echocardiographic parameter of myocardial work incorporates left ventricular pressure into the assessment of left ventricular systolic function and thereby corrects for afterload. We sought to investigate the diagnostic value of myocardial work to identify different grades of stenosis severity in coronary heart disease (CHD) patients with preserved left ventricular ejection fraction and without regional wall motion abnormalities. Methods: One hundred and seventeen consecutive subjects with preserved ejection fraction referred for coronary angiography were randomized and prospectively included in this study. Forty-six in the control group, and 25, 24, and 22 in each of the grade-1, grade-2, and grade-3 CHD groups as classified by the Gensini score. The following indices of myocardial work were assessed with a Vivid E95 Version 203 instrument: global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE). Results: Both GWI (P<0.001) and GCW (P<0.001) decreased significantly in CHD grade-1, increased slightly in CHD grade-2 compared with CHD grade-1, and decreased significantly in CHD grade-3. GWW (P<0.001) increased significantly from CHD grade-1 to CHD grade-3, while GWE (P<0.001) decreased significantly from CHD grade-1 to CHD grade-3. Receiver operating characteristic curves analysis revealed good discrimination between the control group and CHD grade-3 for GWI [area under the curve (AUC): 0.810; 95% confidence interval (CI): 0.691-0.930], GCW (AUC: 0.758; 95% CI: 0.631-0.885), GWW (AUC: 0.754; 95% CI: 0.624-0.885) and GWE (AUC: 0.817; 95% CI: 0.709-0.926). The assessment of intraobserver and interobserver variability in the MW echocardiographic data documented good interclass correlation coefficients (all >0.85). Conclusions: Myocardial work incorporates left ventricular pressure into the assessment of left ventricular systolic function and thereby corrects for afterload. It identifies patients with incipient left ventricular dysfunction caused by chronic ischemia due to CHD. A gradual worsening of myocardial work parameters was observed when comparing patients with higher degrees of stenosis severity. Therefore, adding myocardial work when evaluating patients with suspected CHD may help increase diagnostic accuracy.

8.
Discov Oncol ; 14(1): 109, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37351718

RESUMEN

Nasopharyngeal carcinoma (NPC) is a prevalent cancer in Southern China, North Africa, and Southeast Asia. The translocase of the outer membrane (TOM) 40 is a transporter of mitochondrial proteins, and is involved in ovarian cancer cell growth. However, its role in the progression of NPC is still unclear. We found that TOM40 levels were upregulated in NPC tissues and multiple NPC cell lines. In addition, high TOM40 expression in the tumor tissues was associated with poor overall survival and disease specific survival. TOM40 knockdown in the NPC cell lines inhibited their proliferation in vitro and in vivo. Furthermore, TOM40 silencing also increased intracellular production of reactive oxygen species (ROS) and decreased mitochondrial membrane potential (MMP). Mechanistically, the anti-tumor effects of TOM40 silencing were dependent on the inhibition of AKT/mTOR signaling and activation of p53 signaling. To summarize, TOM40 mediates NPC progression through ROS-mediated AKT/mTOR and p53 signaling. Our findings highlight the potential of TOM40 as a therapeutic target for NPC.

9.
Phytochemistry ; 210: 113668, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37019169

RESUMEN

Phytochemical investigation on the stems of Strophanthus divaricatus led to the isolation of four undescribed cardiac glycosides and one undescribed C21 pregnane, together with eleven known steroids. Their structures were elucidated by a comprehensive analysis of HRESIMS, 1D and 2D NMR spectra. The absolute configuration of 16 was determined by comparison of the experimental and computed ECD spectra. Compounds 1-13 and 15 displayed potent to significant cytotoxicity against human cancer cell lines K562, SGC-7901, A549 and HeLa with IC50 values of 0.02-16.08, 0.04-23.13, 0.06-22.31 and 0.06-15.13 µM, respectively.


Asunto(s)
Antineoplásicos , Strophanthus , Humanos , Glicósidos/química , Pregnanos/farmacología , Pregnanos/química , Línea Celular Tumoral , Estructura Molecular
10.
Clin Exp Hypertens ; 45(1): 2190503, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36924239

RESUMEN

OBJECTIVE: Pulmonary arterial hypertension (PAH) means high blood pressure in the lungs. We aimed to observe the right ventricular size, wall thickness and characteristic functional changes and their associations with PAH in an established model of beagle dogs, and to explore convenient, reliable and sensitive ultrasound indicators for assessing right ventricular remodeling. METHODS: Twenty healthy beagle dogs (8-10 kg) were randomly divided into control group (N-dimethylformamide, n = 10) and dehydromonocrotaline (DHMCT) group (DHMCT, n = 10). N-dimethylformamide or DHMCT was injected through a catheter into the right atrium, and then right heart catheterization, routine echocardiography and two-dimensional speckle tracking imaging (2D-STI) were performed before modeling (0 weeks) and 8, 14 weeks after modeling. Hemodynamic parameters and right ventricular function-related ultrasound data were acquired. At the end of the experiment, the animals were killed and the lung tissues were taken for HE staining. Left and right ventricular walls were separated and weighed respectively, and right ventricular hypertrophy index (RVHI) was measured. The associations of the routine ultrasound data and 2D-STI data at each time point with hemodynamic parameters and RVHI were analyzed. RESULTS: At 0, 8 and 14 weeks, gradual decreases in the right ventricular global longitudinal strain (RVLS) were found in DHMCT group. RVH occurred in DHMCT group, and DHMCT group had a significantly higher RVHI than that of control group (49.83 ± 4.83% vs. 39.80 ± 1.40%, P < .001) and larger pulmonary artery media thickness. RVLS had significant positive correlations with RVSP (r = 0.74, P < .001), mRVP (r = 0.72, P < .001), PASP (r = 0.75, P < .001), mPAP (r = 0.72, P < .001) and PVR (r = 0.68, P < .001). There was a significant positive correlation between RVLS and RVHI (r = 0.74, P < .001). CONCLUSION: The right ventricular function in PAH can be effectively assessed by echocardiography, and RVLS measured by 2D-STI sensitively reflects right ventricular remodeling following PAH.


Asunto(s)
Hipertensión Pulmonar , Hipertensión Arterial Pulmonar , Disfunción Ventricular Derecha , Perros , Animales , Hipertensión Pulmonar/diagnóstico por imagen , Hipertensión Pulmonar/etiología , Remodelación Ventricular , Dimetilformamida , Hipertrofia Ventricular Derecha/diagnóstico por imagen , Hipertrofia Ventricular Derecha/etiología , Función Ventricular Derecha
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