Therapeutic potential of Coumarin-polyphenolic acid hybrids in PD: Inhibition of α-Syn aggregation and disaggregation of preformed fibrils, leading to reduced neuronal inclusion formation.

This study focuses on the discovery of new potential drugs for treating PD by targeting the aggregation of α-Syn. A series of hybrids combining Coumarin and phenolic acid were designed and synthesized. Four particularly promising compounds were identified, showing strong inhibitory effects with IC50 values ranging from low micromolar to submicromolar concentrations, as low as 0.63 µM. These compounds exhibited a higher binding affinity to α-Syn residues and effectively hindered the entire aggregation process, maintaining the proteostasis conformation of α-Syn and preventing the formation of ß-sheet aggregates. This approach holds significant promise for PD prevention. Additionally, these candidate compounds demonstrated the ability to break down preformed α-Syn oligomers and fibrils, resulting in the formation of smaller aggregates and monomers. Moreover, the candidate compounds showed impressive effectiveness in inhibiting α-Syn aggregation within nerve cells, thereby reducing the likelihood of α-Syn inclusion formation resembling Lewy bodies, which highlights their potential for treating PD.

Research on Properties of Silicone-Modified Epoxy Resin and 3D Printing Materials.

A kind of organosilicon intermediate was prepared using isophorone diisocyanate (IPDI), hydroxyl silicone oil (HSO), and hydroxyethyl acrylate (HEA). The organosilicon modification of epoxy resin was realized by introducing a -Si-O- group into the side chain of epoxy resin by chemical grafting. The effects of organosilicon modification of epoxy resin on the mechanical properties systematically discuss its heat resistance and micromorphology. The results indicate that the curing shrinkage of the resin was decreased and the printing accuracy was improved. At the same time, the mechanical properties of the material are enhanced; the IS and elongation at break (EAB) are enhanced by 32.8 and 8.65%, respectively. The brittle fracture is changed to a ductile fracture, and the tensile strength (TS) of the material is decreased. The glass transition temperature (GTT) of the modified epoxy resin increased by 8.46 °C, and T50% and Tmax increased by 1.9 and 6 °C, respectively, indicating that the heat resistance of the modified epoxy resin was improved.

Hybrids of polyphenolic/quinone acids, the potential preventive and therapeutic drugs for PD: Disaggregate α-Syn fibrils, inhibit inclusions, and repair damaged neurons in mice.

Neurotoxic α-Syn fibers, the main components of Lewy bodies, play a key role in the development of PD characterized by a progressive loss of dopaminergic neurons. Here, we designed and synthesized the hybrids of polyphenolic/quinone acids. The candidate compounds showed high α-Syn aggregation inhibitory activities in vitro with IC50 down to 1.6 µM. The inhibition went through the aggregation process by stabilizing the conformation of α-Syn proteostasis and preventing ß-sheets aggregation, especially in the lag phase. Furthermore, the candidate drugs could disintegrate the preformed varisized aggregates into pony-size aggregates and functional monomers and continually inhibit the re-aggregation. The activities of anti-aggregation and aggregates depolymerization result in the reduction of inclusions in neuron cells. The candidate drugs also show high anti-oxidation and low cytotoxicity. They finally repair the damaged neurons in 6-OHDA-lesioned C57 mice and significantly improve PD-like symptoms of the PD model mice. The hybrids are promising molecules for PD prevention and therapy.© 2022 Elsevier Masson SAS. All rights reserved.

Bis-chalcone polyphenols with potential preventive and therapeutic effects on PD: Design, synthesis and in vitro disaggregation activity against α-synuclein oligomers and fibrils.

α-Syn fibrils, which are neurotoxic, play a key role in the development of PD. Maintaining α-Syn proteostasis by suitable molecule ligands is an effective approach to prevent aggregation. Disintegrating the existed oligomers and fibrils into individual α-Syn by small molecular compounds is a more efficient way to treat PD. This work designed and synthesized two series of bis-chalcone polyphenol compounds, which possess a sheet-like conjugated skeleton with stronger H-bonding, π-stacking, and hydrophobic interaction with α-Syn protein residues. Some compounds have shown high α-Syn aggregation inhibitory activities in vitro with IC50 down to 0.64 µM. The inhibition goes throughout the aggregation process from the lag to the stationary phase by stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation, especially in the lag phase. In addition, the inhibitors present good disintegration abilities against the existed α-Syn oligomers and fibrils. The preliminary mechanism studies suggest that the inhibitors could quickly and randomly bind to the specific site closed to the ß-sheet domain in the fibril, resulting in unstable and collapse of the protein fibril and yielding a complex system with aggregates of different sizes and monomers. The inhibitors, which could penetrate the blood-brain barrier, are expected to develop into the drug candidates for PD targeting α-Syn aggregation.

Hybrids of polyphenolic acids and xanthone, the potential preventive and therapeutic effects on PD: Design, synthesis, in vitro anti-aggregation of α-synuclein, and disaggregation against the existed α-synuclein oligomer and fibril.

The misfolding and aggregation of α-Syn are the central mechanism linking and facilitating the other pathological mechanisms of PD. Maintaining α-Syn proteostasis by suitable inhibitors is an effective means to prevent PD. Disintegrating the neurotoxic oligomers and fibrils into the normal functional α-Syn by inhibitors is a more efficient way for PD treatment. This work synthesized two series hybrids of polyphenolic acids and xanthone. The hybrids possess a sheet-like conjugated skeleton and higher binding energies with α-Syn residues. Some compounds present well α-Syn aggregation inhibitory activities in vitro (IC50 down to 2.58 µM). The inhibitory action goes throughout the aggregation process from lag to the stationary phase by stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation. The candidate compounds with appropriate LogP values (2.02-3.11) present good disintegration abilities against the existed α-Syn oligomers and fibrils. The preliminary mechanism studies suggest that the inhibitors could quickly and randomly bind to the specific site closed to the ß-sheet domain in the fibril, resulting in unstable and collapse of the protein fibril, yielding a complex system with aggregates of different sizes and monomers.

Increased risk of cerebrovascular mortality in head and neck cancer survivors aged ≥ 65 years treated with definitive radiotherapy: a population-based cohort study.

BACKGROUND: To investigate the relationship between radiotherapy (RT) and the risk of cerebrovascular mortality (CVM) in head and neck cancer (HNC) survivors aged ≥ 65 years. METHODS: Patients with HNC survivors aged ≥ 65 years diagnosed between 2000 and 2012 were included from the Surveillance, Epidemiology, and End Results database. Kaplan-Meier analysis, Log-rank tests, and Cox proportional-hazards regression models were performed for statistical analyses. RESULTS: We included 16,923 patients in this study. Of these patients, 7110 (42.0%) patients received surgery alone, 5041 (29.8%) patients underwent RT alone, and 4772 (28.2%) patients were treated with surgery and RT. With a median follow-up time of 87 months, 1005 patients died with cerebrovascular disease. The 10-years CVM were 13.3%, 10.8%, and 11.2% in those treated with RT alone, surgery alone, and surgery plus RT, respectively (P < 0.001). The mean time for CVM was shorter in RT alone compared to surgery alone and surgery plus RT (52 months vs. 56-60 months). After adjusting for covariates, patients receiving RT alone had a significantly higher risk of developing CVM compared to those receiving surgery alone (hazard ratio [HR] 1.703, 95% confidence interval [CI] 1.398-2.075, P < 0.001), while a comparable risk of CVM was found between those treated with surgery alone and surgery plus RT (HR 1.106, 95% CI 0.923-1.325, P = 0.274). Similar trends were found after stratification age at diagnosis, gender, tumor location, and marital status. CONCLUSIONS: Definitive RT but not postoperative RT can increase the risk of CVM among older HNC survivors. Long-term follow-up and regular screening for CVD are required for HNC patients who received definitive RT to decrease the risk of CVM.

Early chest CT features of patients with 2019 novel coronavirus (COVID-19) pneumonia: relationship to diagnosis and prognosis.

OBJECTIVE: To determine the consistency between CT findings and real-time reverse transcription-polymerase chain reaction (RT-PCR) and to investigate the relationship between CT features and clinical prognosis in COVID-19. METHODS: The clinical manifestations, laboratory parameters, and CT imaging findings were analyzed in 34 COVID-19 patients, confirmed by RT-PCR from January 20 to February 4 in Hainan Province. CT scores were compared between the discharged patients and the ICU patients. RESULTS: Fever (85%) and cough (79%) were most commonly seen. Ten (29%) patients demonstrated negative results on their first RT-PCR. Of the 34 (65%) patients, 22 showed pure ground-glass opacity. Of the 34 (50%) patients, 17 had five lobes of lung involvement, while the 23 (68%) patients had lower lobe involvement. The lesions of 24 (71%) patients were distributed mainly in the subpleural area. The initial CT lesions of ICU patients were distributed in both the subpleural area and centro-parenchyma (80%), and the lesions were scattered. Sixty percent of ICU patients had five lobes involved, while this was seen in only 25% of the discharged patients. The lesions of discharged patients were mainly in the subpleural area (75%). Of the discharged patients, 62.5% showed pure ground-glass opacities; 80% of the ICU patients were in the progressive stage, and 75% of the discharged patients were at an early stage. CT scores of the ICU patients were significantly higher than those of the discharged patients. CONCLUSION: Chest CT plays a crucial role in the early diagnosis of COVID-19, particularly for those patients with a negative RT-PCR. The initial features in CT may be associated with prognosis. KEY POINTS: • Chest CT is valuable for the early diagnosis of COVID-19, particularly for those patients with a negative RT-PCR. • The early CT findings of COVID-19 in ICU patients differed from those of discharged patients.

Prearrest hypothermia improved defibrillation and cardiac function in a rabbit ventricular fibrillation model.

BACKGROUND: Hypothermia when cardiopulmonary resuscitation begins may help achieve defibrillation and return of spontaneous circulation (ROSC), but few data are available. OBJECTIVE: The objective of this study was to determine whether prearrest hypothermia improved defibrillation and cardiac function in a rabbit ventricular fibrillation (VF) model. RESULTS: Thirty-six New Zealand rabbits were randomized equally to receive normothermia (Norm) (~39°C), post-ROSC hypothermia (~33°C), or prearrest hypothermia (~33°C). Ventricular fibrillation was induced by alternating current. After 4 minutes of VF, rabbits were defibrillated and given cardiopulmonary resuscitation until ROSC or no response (≥30 minutes). Hemodynamics and electrocardiogram were monitored; N-terminal pro-brain natriuretic peptideand troponin I were determined by enzyme-linked immunosorbent assay. Myocardial histology and echocardiographic data were evaluated. First-shock achievement of perfusion rhythm was more frequent in prearrest than normothermic animals (7/12 vs 1/12; P=.027). After ROSC, dp/dtmax was higher in prearrest than normothermic animals (P<.001). Left ventricular end-systolic pressure was higher in prearrest than normothermic animals (P=.001). At 240 minutes after ROSC, troponin I and N-terminal pro-brain natriuretic peptide were lower in prearrest than normothermic animals (15.74±2.26 vs 25.09±1.85 ng/mL and 426±23 vs 284±45 pg/mL, respectively), the left ventricular ejection fraction and cardiac output were lower in the Norm group than other 2 groups (P<.01). Myocardial histology was more disturbed in normothermic than post-ROSC and prearrest animals, but was not different in the latter 2 groups. CONCLUSIONS: Induction of hypothermia before VF led to improved cardiac function in a rabbit VF model through improving achievement of perfusing rhythm by first-shock defibrillation and facilitating resuscitation.

[Roles of dendritic cells in mediating decreased delayed type hypersensitivity responses after trauma].

OBJECTIVE: To study the effects of hemorrhage combined with closed fracture on delayed type hypersensitivity (DTH) responses in mice and to explore the relevant mechanisms. METHODS: DTH responses were induced with 2, 4-dinitro-1-fluorobenzene (DNFB) or fluorescein isothiocyanate (FITC) skin painting after injury, and single cell suspensions from pooled inguinal lymph nodes were analyzed by flow cytometry for FITC+ cells and dendritic cells (DC). The ability of cells from pooled inguinal lymph nodes was tested 24 hours after skin painting with DNFB in transferring sensitization for DTH to DNFB. RESULTS: The DTH responses after injury decreased significantly compared with that of sham-injured mice (P<0.01). Flow cytometry showed that FITC+ cells, FITC+/CD11c+ cells, and FITC+/CD11c+ / major histocompatibility complex II+ cells were all significantly decreased after trauma (P<0.01). The ability of cells to transfer sensitization for DTH to DNFB also declined (P<0.01). CONCLUSION: Hemorrhage combined with closed fracture decreases the DTH responses in mice, which may be attributed to the reduced antigen-presenting capacity of DC in the injured mice.

Anti-inflammatory effects of a novel peptide designed to bind with NF-kappaB p50 subunit.

AIM: To explore the anti-inflammatory effects of a novel peptide designed to bind with the NF-kappaB p50 subunit. METHODS: The affinity of the peptide binding with p50 was measured with a biosensor. Levels of tumor necrosis factor-alpha(TNF-alpha) and interleukin 6 (IL-6) from a human acute monocytic leukemia cell line (THP-1) treated with lipopolysaccharide (LPS) were measured using the ELISA method. In vivo anti-inflammatory effects of the peptide were tested with phorbol myristate acetate (PMA)-induced ear edema and zymosan A-induced peritonitis in mice. RESULTS: The peptide has the ability to interact with the NF-kappaB p50 subunit and can effectively inhibit TNF-alpha and IL-6 production in the THP-1 cell line, PMA-induced ear edema and zymosan A-induced peritonitis in mice. CONCLUSION: The peptide may have therapeutic potential for the treatment of local acute inflammation.

In vitro characteristics of poly(lactic-co-glycolic acid) microspheres incorporating gelatin particles loading basic fibroblast growth factor.

AIM: To construct a sustained drug release system for basic fibroblast growth factor (bFGF). With this special system, bFGF can be used to repair an injured peripheral nerve, injured spinal cord, or as a carrier for other drugs that need to be released over a long time. METHODS: Microsphere composite was prepared by encapsulating bFGF into gelatin particles with poly(lactic-co-glycolic acid) (PLGA) as its outer-coating. The encapsulation was conducted by a phase separation method. RESULTS: The average diameter of the gelatin particle-PLGA microsphere composite was 5-18 mum, and bFGF-loading efficiency was up to 80.5%. The bFGF releasing experiment indicated that this new composite system could release bFGF continuously and protect bFGF from denaturation. CONCLUSION: A modified approach was successfully employed to develop a biodegradable system for sustained release of the drug of bFGF in vitro.

An in vivo experimental system to study sugar phloem unloading in ripening grape berries during water deficiency stress.

An in vivo experimental system-called the 'berry-cup' technique-was developed to study sugar phloem unloading and the accumulation of sugar in ripening grape berries. The berry-cup system consists of a single peeled grape berry immersed in a buffer solution in a cup prepared from a polypropylene syringe. A small cross-incision (2 mm in length) is made on the stylar remnant of a berry during its ripening phase, the skin of the berry then being easily peeled off, exposing the dorsal vascular bundles without damaging either these or the pulp tissue of the berry. The sites of sugar phloem unloading are thus made directly accessible and may be regulated by the buffer solution. In addition, the unloaded photoassimilates are easily transported into the buffer solution in the berry-cup. With the berry-cup technique, it takes 60 min to purge the sugar already present in the apoplast, after which the amount of sugar in the buffer solution is a direct measure of the sugar unloading from the grape berry phloem. The optimum times for sampling were 20 or 30 min, depending on the type of experiment. Sugar phloem unloading was significantly inhibited by the inclusion of either 7.5 mm NaF or 2.5 mm PCMB in the buffer solution. This study indicates that sugar phloem unloading in ripening grape berries is via the apoplastic network and that the process requires the input of energy. The system was shown to be an appropriate experimental system with which to study sugar phloem unloading in ripening grape berries, and was applied successfully to the study of berry sugar unloaded from grapevines subjected to water stress. The results showed that water deficiency inhibits sugar unloading in grape berries.