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1.
Cancer Manag Res ; 13: 2171-2180, 2021.
Article in English | MEDLINE | ID: mdl-33688260

ABSTRACT

BACKGROUND: Originating from extranodal organs or tissues, primary extranodal lymphoma (PENL) acts in different primary sites with diverse clinical performances and PENL has remarkable geographical differences and lacks the relevant reports in each region. PATIENTS AND METHODS: Two hundred and twenty PENL patients were enrolled, and the relevant clinical and laboratory indicators were analyzed. In addition, statistical methods were applied to analyze the effects of different factors on overall survival (OS) and progression-free survival (PFS) of patients. RESULTS: The three most frequent primary sites of PENL are the digestive system, head and neck, and central nervous system. The patients were classified into groups based on their risk status, resulting in low-risk, medium-low-risk, medium-high-risk, and high-risk, and their respective 3-year OS values were calculated, which showed that 121 patients (55%) were in the low-risk group and 3-year OS was 85.2% (25.9% medium-low-risk, 3-year OS 66.6%; 15% medium-high-risk, 3-year OS 61.9%; 4.09% high risk, 3-year OS 45.7%). A multivariate analysis of the Cox regression demonstrated that serum beta 2-microglobulin (ß2-MG) and lactate dehydrogenase (LDH) were independent prognostic factors for OS and PFS, respectively. Both the performance status and pathological subtypes were independent prognostic factors for OS and PFS. CONCLUSION: The correlated independent risk factors such as ß2-MG, LDH, performance status, and pathological subtypes, were helpful for effectively determining the prognosis of PENL patients and guiding treatment.

2.
Eur J Med Chem ; 215: 113267, 2021 Apr 05.
Article in English | MEDLINE | ID: mdl-33639344

ABSTRACT

Inhibitors of the proteasome have been extensively studied for their applications in the treatment of human diseases such as hematologic malignancies, autoimmune disorders, and viral infections. Many of the proteasome inhibitors reported in the literature target the non-primed site of proteasome's substrate binding pocket. In this study, we designed, synthesized and characterized a series of novel α-keto phenylamide derivatives aimed at both the primed and non-primed sites of the proteasome. In these derivatives, different substituted phenyl groups at the head group targeting the primed site were incorporated in order to investigate their structure-activity relationship and optimize the potency of α-keto phenylamides. In addition, the biological effects of modifications at the cap moiety, P1, P2 and P3 side chain positions were explored. Many derivatives displayed highly potent biological activities in proteasome inhibition and anticancer activity against a panel of six cancer cell lines, which were further rationalized by molecular modeling analyses. Furthermore, a representative α-ketoamide derivative was tested and found to be active in inhibiting the cellular infection of SARS-CoV-2 which causes the COVID-19 pandemic. These results demonstrate that this new class of α-ketoamide derivatives are potent anticancer agents and provide experimental evidence of the anti-SARS-CoV-2 effect by one of them, thus suggesting a possible new lead to develop antiviral therapeutics for COVID-19.


Subject(s)
Amides/pharmacology , Antineoplastic Agents/pharmacology , Antiviral Agents/pharmacology , Ketones/pharmacology , Proteasome Inhibitors/pharmacology , SARS-CoV-2/drug effects , Amides/chemical synthesis , Amides/metabolism , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/metabolism , Antiviral Agents/chemical synthesis , Antiviral Agents/metabolism , Binding Sites , Calpain/chemistry , Calpain/metabolism , Cell Line, Tumor , Coronavirus 3C Proteases/chemistry , Coronavirus 3C Proteases/metabolism , Drug Screening Assays, Antitumor , Humans , Ketones/chemical synthesis , Ketones/metabolism , Microbial Sensitivity Tests , Molecular Docking Simulation , Molecular Dynamics Simulation , Molecular Structure , Proteasome Endopeptidase Complex/chemistry , Proteasome Endopeptidase Complex/metabolism , Proteasome Inhibitors/chemical synthesis , Proteasome Inhibitors/metabolism , Protein Binding , Structure-Activity Relationship
3.
Sensors (Basel) ; 20(18)2020 Sep 06.
Article in English | MEDLINE | ID: mdl-32899933

ABSTRACT

The piezoceramic actuated stages have rate-dependent hysteresis nonlinearity, which is not simply related to the current and historical input, but also related to the frequency of the input signal, seriously affects its positioning accuracy. Consider the influence of frequency on hysteresis modeling, a rate-dependent hysteresis nonlinearity model that is based on Krasnoselskii-Pokrovskii (KP) operator is proposed in this paper. A hybrid optimization algorithm of improved particle swarm optimization and cuckoo search is employed in order to identify the density function of rate-dependent KP model, avoiding the blind search process caused by the high randomness of Levy's flight in the cuckoo search algorithm, and improving the parameter identification performance. For the sake of eliminating the hysteresis characteristics, an inverse feed-forward compensation control that is based on recursive method is proposed without any additional conditions, and a feed-forward compensation controller is designed accordingly. The experimental results show that, under different frequency input signals, as compared with the classic KP model, the proposed rate-dependent KP model can accurately describe the rate-dependent hysteresis characteristics of the piezoceramic actuated stages, and the recursive inverse feed-forward compensation control method can effectively mitigate the hysteresis behaviors.

4.
ISA Trans ; 99: 305-321, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31515095

ABSTRACT

This paper focuses on an adaptive fuzzy based dynamic surface sliding mode control (ADSSMC) strategy for multi-machine power systems with SVC. The main characteristics of the proposed ADSSMC strategy are: (1) System robustness and the convergency speed of all surface error are enhanced by combining dynamic surface control with sliding mode, leading to the structural complexity of the controller in backstepping control scheme is eliminated; (2) By introducing an error performance conversion function, the errors of desired trajectory and system output are always within a predetermined range; (3) In the adaptive regulation laws, the number of estimated parameters of the control system is significantly reduced due to the utilization of the estimations of weight vector norm instead of the weight vectors itself. The stability analysis proves that the proposed ADSSMC control strategy can guarantee the boundaries of all signals in the closed-loop control system. Experimental results verify the effectiveness of the proposed ADSSMC scheme.

5.
J Org Chem ; 78(23): 12009-17, 2013 Dec 06.
Article in English | MEDLINE | ID: mdl-24195678

ABSTRACT

We have developed a highly efficient cascade sequence for asymmetric synthesis of indoloquinolizidines with absolute control of cis-H2/H12b relative geometry in good to excellent yields and excellent enantioselectivities. This cascade was triggered by the Ru(II)-TsDPEN-catalyzed asymmetric transfer hydrogenation of imino diesters, with subsequent spontaneous lactamization with discrimination between the two diastereotopic 2-alkoxy-2-oxoethyl groups. The synthetic utility of this strategy was demonstrated by the asymmetric preparation of dihydrocorynantheol, geissoschizol, and isogeissoschizol.


Subject(s)
Esters/chemistry , Imines/chemistry , Organometallic Compounds/chemistry , Quinolizidines/chemical synthesis , Catalysis , Hydrogenation , Molecular Structure , Quinolizidines/chemistry , Stereoisomerism
7.
Org Lett ; 12(23): 5366-9, 2010 Dec 03.
Article in English | MEDLINE | ID: mdl-21062039

ABSTRACT

An expedient diastereoselective synthesis of highly functionalized indolo[2,3-α]quinolizidines adopting a cis H2/H12b geometry has been realized by a Pictet-Spengler/lactamization cascade sequence. The absolute stereochemistry at C2, C3, and C12b was governed by the originally created chirality of the Michael adduct through organocatalyzed conjugate addition of dialkyl malonates to α,ß-unsaturated aldehydes.


Subject(s)
Indoles/chemistry , Lactams/chemistry , Quinolizidines/chemical synthesis , Crystallography, X-Ray , Models, Molecular , Molecular Structure , Stereoisomerism
8.
Chem Commun (Camb) ; 46(16): 2733-5, 2010 Apr 28.
Article in English | MEDLINE | ID: mdl-20369165

ABSTRACT

The enantioselective three-component Michael addition-Pictet-Spengler sequence of beta-ketoesters 1, alpha,beta-unsaturated aldehydes 2 and tryptamines 4 represents a facile and rapid one-pot access to highly substituted indoloquinolizidines in moderate to excellent yields and good to excellent enantioselectivities.


Subject(s)
Indoles/chemistry , Quinolizidines/chemistry , Catalysis , Combinatorial Chemistry Techniques , Cyclization , Molecular Structure , Organic Chemicals/chemistry , Stereoisomerism
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