FBDD and drugs originated from FBDD / 药学学报

The binding of small molecule drugs to targets is mostly through non-covalent bonds, and hydrogen bond, electrostatic, hydrophobic and van der Waals interactions function to maintain the binding force. The more these binding factors lead to strong bindings and high activities. However, it is often accompanied by the increase of molecular size, resulting in pharmacokinetic problems such as membrane penetration and absorption, as well as metabolism, which ultimately affects the drug success. Fragment-based drug discovery (FBDD) is to screen high-quality fragment library to find hits. Combine with structural biology, FBDD generates lead compounds by means of fragment growth, linking and fusion, and finally drug candidates by the optimization operation. During the value chain FBDD is closely related to structure-based drug discovery (SBDD). In this paper, the principle of FBDD is briefly described by several launched drugs.

An overview of disease treatment strategies targeting the alternative splicing of pre-mRNA / 药学学报

Alternative splicing of pre-messenger RNA (pre-mRNA) is a crucial mechanism for the diversity of the human transcriptome and proteome. Alternative splicing is a complex gene regulation process. Whole-transcriptome analysis shows that 95% of human exonic genes are alternatively spliced, involving various cis-acting elements and trans-acting factors. Any changes in any component or step may cause erroneous splicing events and lead to the occurrence of various related diseases. In addition to gene replacement therapy that directly changes the splicing results, RNA splicing modification is expected to become a new therapeutic strategy to alleviate or treat diseases by targeting and correcting abnormal pre-mRNA splicing. Splicing modification tools currently developed including RNA trans-splicing, antisense oligonucleotides, small interfering RNA, and small molecule drugs can correct abnormal splicing through different ways. This article reviews the resent progress of epigenetic regulation of pre-mRNA alternative splicing in recent years, and discusses the occurrence and regulation of alternative splicing, the types of diseases caused by related splicing defects, and the current-used tools for targeting and altering splicing. The importance of splicing modification strategies in the future treatment of human diseases is envisioned.

Olecranon osteotomy approach for Dubberley type Ⅲ coronal fractures of the distal humerus / 中国骨伤

OBJECTIVE@#To retrospectively analyze the clinical efficacy of olecranon osteotomy approach in the treatment of Dubberley type Ⅲ coronal fractures of the distal humerus and summarize the treatment experience.@*METHODS@#From January 2016 to June 2020, 17 patients (5 males and 12 females) with Dubberley type Ⅲ coronal fractures of the distal humerus were treated by olecranon osteotomy approach. The age ranged from 37 to78 years old with an average of (58.5±12.9) years old. According to Dubberley classification, there were 5 cases of type Ⅲ A and 12 cases of type Ⅲ B. The curative effect was evaluated using the Borberg-Morrey elbow function score. The flexion, extension and rotation range of motion of the elbow joint, complications and postoperative imaging evaluation were recorded.@*RESULTS@#All the 17 patients got bony union. The follow-up time ranged from 12 to 33 months with an average of (15.6±5.6) months. There was 1 case of ischemic necrosis of capitulum humeri, 2 cases of traumatic arthritis and 1 case of heterotopic ossification, 1 case of malunion of fracture. The range of motion was (114.80±19.50) °. The Broberg-Morrey score was 85.3±8.2, excellent in 5 cases, good in 9 cases, fair in 3 cases and poor in 0 case.@*CONCLUSION@#Through olecranon osteotomy approach, the articular surface of distal humerus could be fully exposed, and the operation is convenient. Anatomical reduction and rigid fixation of the articular surface of distal humerus are the key factors for the succesful outcome.

On improving the activity and selectivity of small molecule drugs / 药学学报

Although small molecule drugs (SMD) are still mainstream for the treatment of diseases, large molecule biologicss of many advantages, pose a challenge to the further discovery and use of SMD. The advantages of SMD are the convenience of oral administration and good patient compliance. However, the challenge with SMD is to integrate the PD, PK, selectivity and safety into a chemical structure. Because of their small size and surface area they often bind to various proteins, and off-target actions can cause adverse reactions. In this sense, selectivity is critical. Based upon target as the core to construct a chemical structure, it is necessary to consider the requirements of all the attributes, but achievement of the full-dimensional optimization is difficult. Modern drug discovery has been greatly enhanced by molecular biology and structural biology, and new strategies and technologies have emerged, which have created many successful medicines. For example, under the guidance of structural biology, covalent binding drugs connect moderate "electrophilic warheads" to the appropriate positions of molecules, and upon binding to their targets the electrophiles are irreversibly linked to the target by covalent bonds. Molecular biology can be directly applied to the development of antibody-coupled drugs (ADC). The antibody (A) acts as a carrier and a guide (for PK), and carries toxic molecules (D) into cancer cells, thus playing a killing role (for PD). The separate pharmacodynamic and pharmacokinetic entities are coupled (C) by linkers. PROTACs are also bifunctional molecules, which recruit a target protein and ubiquitin ligase E3 to form a ternary complex, which then acts as a catalyst to ubiquitinate the target protein and lead to degradation by the proteasome. In addition, in recent years, the combination of two fixed-dose drugs has improved selectivity, safety, and long-term benefit with many severe diseases, and can be regarded as an innovative strategy of physical combination. This review discusses some successful examples to briefly present the principles from the perspective of medicinal chemistry and therapeutic application.

Perspective of CADD and AIDD in medicinal chemistry / 药学学报

Artificial intelligence-aided drug discovery (AIDD) is a new version of computer-aided drug discovery (CADD). AIDD is featured in significantly promoting the performance of conventional CADD. AI markedly enhances the learning ability of CADD. In the 1960s, CADD was established from conventional QSAR approaches, which mainly used regression approaches to derive substructure-activity relationship for compounds with a common scaffold, and guide drug molecular design, figure out the binding features of drugs, and identify potential drug targets. Since the 1990s, structural biology has provided three-dimensional structures of drug targets, enabling drug discovery based on target structure (SBDD), fragment-based drug discovery (FBDD), and structure-based virtual screening (SBVS) with CADD approaches. In the past 30 years, many first in class (FIC) and best in class (BIC) drugs were discovered with CADD. Now, AIDD will further revolutionize CADD by reducing human interventions and mining big chemical and biological data. It is expected that AIDD will significantly enhance the abilities of CADD, virtual screening and drug target identification. This article tries to provide perspectives of CADD and AIDD in medicinal chemistry with case studies.

Drug discovery from viewpoint of medicinal chemists / 药学学报

Taking patient needs as the core and realizing clinical value as the guidance are the purpose and path of drug discovery. Whether the first-in-class drug or follow-on drugs are all to meet the demands of patients for drugs that are not treatable or more safe and effective. In order to realize clinical value, innovative drugs driven by basic biological research include three elements: understanding the molecular mechanism of pathogenesis; Grasping the microscopic features of the disease; clarifying the mechanism of action of drugs. The interrelation among the three is the translational medicine, and the medicinal chemistry plays an important role in the translations. That is, based on the results of basic research in biology/medicine, knowledge of the molecular mechanism of disease depends upon the establishment of various in vitro/in vivo models to find the key node and molecular regulation for the treatment of disease. Combined with the knowledge of gene deletion and variation, proteomics, epigenetics and other technologies, the molecular mechanism of disease provides multi-molecular information on the level of gene, proteins, enzymes, receptors, ion channels and signal transduction for molecular drug design. Insight into the microscopic characteristics of diseases would deepen the understanding of the molecular mechanism of the pathogenesis, as well as provide a feasible scientific path for the creation of new drugs. When the molecular mechanism of disease and the action mechanism of drugs are clarified, we have a deeper and wider understanding of the application of existing drugs (or active compounds), and may offer new ideas for drug design and application. In this translational process the medicinal chemistry plays a key role which requires medicinal chemists to break through the habitual thinking and working mode, backtracking (upstream) to basic research and its achievements and applying to the direction of creating new drugs in time, as well as paying attention to the clinical requirements (downstream) and implementing the specific content of the transformation process for the R&D of innovative drugs.

Analysis of biolo artificial neural network in prediction of aerobic exercise index based on algorithm / Análise de rede neural artificial na predição do índice de exercício aeróbio baseada em algorítimo / Análisis de red neuronal artificial en la predicción del índice de ejercicio aeróbico

ABSTRACT Objective: To study the relationship between aerobic activity and cardiac autonomic nerve activity by artificial neural network algorithm and biological image fusion; because of the artificial neural network model (ANN) problems, biological image processing technology is introduced based on ANN. Methods: An Ann under biological image intelligence algorithm is proposed, a classifier suitable for electrocardiograph (ECG) screening is designed, and an ECG signal screening system is successfully established. Moreover, the data set of normal recovered ECG signals of the subjects during the experimental period is constructed, and a classifier is used to extract the characteristic data of a normal ECG signal during the experimental period. Results: The changes in resting heart rate and other physical health indicators are analyzed by combining resting physiological indicators, namely heart rate, body weight, body mass index and body fat rate. The results show that the self-designed classifier can efficiently process the ECG images, and long-term regular activities can improve the physical conditions of most people. Most subjects' body weight and body fat rate decrease with the extension of experiment time, and the resting heart rate decreases relatively. Conclusions: Certain indicators can be used to predict a person's dynamic physical health, which indicates that the experimental research of index prediction in this research has a good effect, which not only extends the application of artificial neural network but also lays a foundation for the research and implementation of ECG intelligent testing wearable devices. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Objetivo: Com o objetivo de estudar a relação entre atividade aeróbia e atividade nervosa autonômica cardíaca por algoritmo de rede neural artificial e fusão biológica de imagens, tendo em vista os problemas existentes no modelo de rede neural artificial (RNA), é introduzida a tecnologia de processamento biológico de imagens com base em ANN. Métodos: um algoritmo de inteligência biológica de imagem Ann é proposto, um classificador adequado para triagem eletrocardiográfica (ECG) é projetado e um sistema de triagem de sinal de ECG é estabelecido com sucesso. Além disso, o conjunto de dados de sinais de ECG normais recuperados dos sujeitos durante o período experimental é construído e um classificador é usado para extrair os dados característicos de um sinal de ECG normal durante o período experimental. Resultados: As alterações na frequência cardíaca em repouso e outros indicadores de saúde física são analisadas pela combinação de indicadores fisiológicos de repouso, a saber, frequência cardíaca, peso corporal, índice de massa corporal e índice de gordura corporal. Os resultados mostram que o classificador autodesenhado pode processar com eficiência as imagens de ECG, e as atividades regulares de longo prazo podem melhorar as condições físicas da maioria das pessoas. O peso corporal e a taxa de gordura corporal da maioria dos indivíduos diminuem com a extensão do tempo do experimento, e a freqüência cardíaca em repouso diminui relativamente. Conclusões: Certos indicadores podem ser usados para prever a saúde física dinâmica de uma pessoa, o que indica que a pesquisa experimental de predição de índice nesta pesquisa tem um bom efeito, que não apenas estende a aplicação da rede neural artificial, mas também estabelece uma base para a pesquisa e implementação de dispositivos vestíveis de teste inteligente de ECG. Nível de evidência II; Estudos terapêuticos- investigação dos resultados do tratamento.

RESUMEN Objetivo: Para estudiar la relación entre la actividad aeróbica y la actividad del nervio autónomo cardíaco mediante el algoritmo de red neuronal artificial y la fusión de imágenes biológicas, ante los problemas existentes en el modelo de red neuronal artificial (ANN), se introduce la tecnología de procesamiento de imágenes biológicas basada en ANA. Métodos: Se propone un algoritmo de inteligencia de imagen biológica de Ann, se diseña un clasificador adecuado para el cribado electrocardiógrafo (ECG) y se establece con éxito un sistema de cribado de señales de ECG. Además, se construye el conjunto de datos de las señales de ECG recuperadas normales de los sujetos durante el período experimental, y se utiliza un clasificador para extraer los datos característicos de una señal de ECG normal durante el período experimental. Resultados: Los cambios en la frecuencia cardíaca en reposo y otros indicadores de salud física se analizan combinando indicadores fisiológicos en reposo, a saber, frecuencia cardíaca, peso corporal, índice de masa corporal y tasa de grasa corporal. Los resultados muestran que el clasificador de diseño propio puede procesar de manera eficiente las imágenes de ECG, y las actividades regulares a largo plazo pueden mejorar las condiciones físicas de la mayoría de las personas. El peso corporal y la tasa de grasa corporal de la mayoría de los sujetos disminuyen con la extensión del tiempo del experimento, y la frecuencia cardíaca en reposo disminuye relativamente. Conclusiones: Ciertos indicadores pueden usarse para predecir la salud física dinámica de una persona, lo que indica que la investigación experimental de predicción de índices en esta investigación tiene un buen efecto, lo que no solo extiende la aplicación de la red neuronal artificial sino que también sienta las bases para la investigación. e implementación de dispositivos portátiles de prueba inteligente de ECG. Nivel de evidencia II; Estudios terapéuticos- investigación de los resultados del tratamiento.

Research advances on the chemical components and pharmacological activities of Zanthoxyli Radix / 药学学报

Zanthoxyli Radix is a traditional Chinese medicine. It can be used for the treatment of wind-cold-dampness arthralgia, muscle and bone pain, fall fracture, hernia, sore throat, toothache and other diseases. Due to possessing many excellent and mild pharmacological properties, there are lots of reports about Zanthoxyli Radix worldwide. At present, more than 100 bioactive components have been extracted and purified from Zanthoxyli Radix. Nitidine chloride (NC), one of the most important alkaloids in Zanthoxyli Radix, has the activities of anti-tumor, anti-inflammation, anti-bacteria, etc. In this review, we summarize the chemical components of Zanthoxyli Radix, pharmacological activity and mechanism of action of NC to provide references for further research and utilization of Zanthoxyli Radix.

Bruceantin inhibits proliferation, migration and invasion of non-small cell lung cancer H1299 cells by up-regulating miR-29a-3p / 药学学报

We investigated the inhibitory effect and mechanism of action of bruceantin (BCT) on the proliferation, invasion and migration of non-small cell lung cancer (NSCLC) cells. The cytotoxic activity of BCT was measured by MTT assay; a colony forming assay, wound healing assay, and a Transwell assay were used to investigate the anti-proliferative, anti-migration, and anti-invasion effects, respectively; immunoblotting and RT-qPCR were used to detect the expression of related proteins, miRNA, and mRNA, respectively, that were involved in cell proliferation, migration, and invasion. Two gene prediction websites were used to predict the downstream target gene of miRNA. Our results show that BCT has a potent cytotoxic effect on NSCLC cell lines, with a half maximal inhibitory concentration (IC50) of BCT against H1299, PC-9, and A549 of 0.12 ± 0.02, 0.31 ± 0.20, and 2.07 ± 0.70 μmol·L-1, respectively. When H1299 cells were treated with 0.03, 0.15, and 0.75 μmol·L-1 BCT for 24 h, the proliferation, migration, and invasive ability were inhibited in a concentration-dependent manner. It is worth noting that the expression level of miRNAs related to cell migration and invasion, such as miR-29a-3p, miR-21-3p, miR-183-5p, and miR-34b-5p increased with the concentration of BCT, especially for miR-29a-3p. Using the two gene prediction websites, we predict that integrin β1 (ITGB1) may be the target gene of miR-29a-3p; immunoblot results further show that a variety of proteins related to cell proliferation, migration, and invasion, such as various proteins of the integrin family, β-catenin, p-Src, and vascular endothelial growth factor, all decreased in a concentration-dependent manner, among which the reduction of ITGB1 protein was the most obvious. RT-qPCR results showed that there was no change in ITGB1 mRNA expression. We speculate that BCT might inhibit the expression of ITGB1 protein by up-regulating miR-29a-3p independent of its mRNA level. The in-depth mechanism needs to be further explored. This study suggests that BCT has the potential for further development in the treatment of NSCLC.

Mathematical model construction and analysis of the effect of estradiol on the electrical activity of gastric antrum in female rabbits / 解剖学报

Objective To investigate the expression of estrogen receptor in gastric antrum and the effect of estrogen on electrical activity of gastric antrum smooth muscle in female rabbits in virtue of the constructed mathematical model in order to explore the regulation of estrogen on gastric motility. Methods Using immunofluorescence to observe the expression of estrogen receptor in gastric antrum. Using BL-420F bio monitor to monitor: Comparing the difference of antral electromyography index between rabbits in ovariectomized group and rabbits in sham operating group; Observing the dose-response relationship between doses of estradiol (0,0. 1,0. 15,0. 2,0. 25 and 0. 3 mg/ kg). To construct the mathematical model, and to analyze the dose-response relationship and mechanism of action. Rresult The expression of estrogen receptor in the antral wall of the stomach was negative. The activity index of gastric antrum myoelectric activity was significantly decreased after ovarian ablation (P<0. 01). With the increase of estradiol dose, the activity index of gastric antrum muscle increased and then decreased. Analysis of variance showed that the difference of antral electromyographic activity index between adjacent groups was significant (P<0. 05) or extremely significant (P<0. 01). Taking the estradiol dose as the independent variable x, the antral electromyography activity index was the dependent variable y, and the fitting wass obtained: y= 2. 80 + 5. 65 × exp{ -0. 5 × [(x-0. 159) / 0. 038 ]

The urinary metabolomics of Astragalus Radix and Dioscoreae Rhizomacomes reveal possible therapeutic mechanisms in the treatment of type 2 diabetes / 药学学报

sup>1H NMR-based metabonomic analysis was used to elucidate the hypoglycemic mechanism of Astragalus Radix and Dioscoreae Rhizomacomes. Thirty-seven SD rats were divided into four groups: model group (M group), control group (C group), Astragalus Radix and Dioscoreae Rhizomacomes group (HS group), metformin group (Y group). A T2DM model was induced with a high fat diet and streptozotocin (STZ). Drug was continuously administered for 8 weeks, after which blood and the kidneys were collected to determine the biochemical index and the kidney coefficients of each group. Using 1H NMR metabolomics technology, we measured the metabolites in the urine of rats in each group to identify appropriate biomarkers. The results showed that total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (L-DLC), blood urea nitrogen (BUN), hemoglobin A1c (HbA1c) and the kidney coefficients were significantly increased with high density lipoprotein (H-DLC) significantly decreased in the diabetic group, but these changes were largely reversed with treatment with Astragalus Radix and Dioscoreae Rhizomacomes. A total of 20 biomarkers were found in rat urine in the diabetic group and Astragalus Radix and Dioscoreae could reverse the changes of 16 of these metabolites to varying degrees, similar to that of metformin (200 mg·kg-1). The changes in metabolomics mainly involved butanoate metabolism, the tricarboxylic acid (TCA) cycle, taurine and hypotaurine metabolism, synthesis and degradation of ketone bodies, and pyruvate metabolism. Dioscoreae Rhizomacomes and Astragalus Radix may have a therapeutic role in the treatment of diabetes through the above five metabolic pathways, revealing the possible therapeutic mechanisms for Dioscoreae Rhizomacomes and Astragalus Radix.

Efficacy of Moxifloxacin against in Zebrafish Model / 生物医学与环境科学（英文）

Objective@#Moxifloxacin (MFX) shows good activity against and can be a possible antibiotic therapy to treat infection; however, other studies have shown a lower or no activity. We aimed to evaluate MFX activity against using zebrafish (ZF) model .@*Methods@#A formulation of labeled with CM-Dil was micro-injected into ZF. Survival curves were determined by recording dead ZF every day. ZF were lysed, and colony-forming units (CFUs) were enumerated. Bacteria dissemination and fluorescence intensity in ZF were analyzed. Inhibition rates of MFX and azithromycin (AZM, positive control) were determined and compared.@*Results@#Significantly increased survival rate was observed with different AZM concentrations. However, increasing MFX concentration did not result in a significant decrease in ZF survival curve. No significant differences in bacterial burdens by CFU loads were observed between AZM and MFX groups at various concentrations. Bacterial fluorescence intensity in ZF was significantly correlated with AZM concentration. However, with increasing MFX concentration, fluorescence intensity decreased slightly when observed under fluorescence microscope. Transferring rates at various concentrations were comparable between the MFX and AZM groups, with no significant difference.@*Conclusion@#MFX showed limited efficacy against using ZF model. Its activity needs to be confirmed.

The mechanism of parthenolide strengthen vorinostat on inhibiting the proliferation of A549 non-small cell lung cancer cells / 药学学报

This research explored the synergistic effects and the mechanism of parthenolide (PTL) and vorinostat (suberoylanilide hydroxamic acid, SAHA) on the proliferation of A549 non-small cell lung cancer cells. The combination effect of PTL and SAHA was detected by cell counting kit-8 (CCK-8) and colony formation assays. Scratch test was performed to detect cell migration. Annexin V-fluorescein isothiocyanate isomer/propidium iodide (FITC/PI) flow cytometry and Western blot analyses were used to determine cell apoptosis and its mechanism. The results showed that combination of PTL and SAHA inhibited the proliferation and migration of A549 with a synergistic effect compared to the single-drug groups. The combination of PTL and SAHA had synergistic effect to induce cell apoptosis by regulating p53 and c-myc pathways, and affected the expression levels of poly ADP-ribose polymerase (PARP), cysteinyl aspartate specific proteinase (caspase)-9, and caspase-3. Taken together, this study shows that combination of PTL and SAHA has synergistic effect, induces cell apoptosis and inhibits A549 proliferation, which is likely to be a novel strategy for the treatment of non-small cell lung cancer.

Examples of biology-driven drug design / 药学学报

Pharmacological activity and drug likeness depend in principle upon the microscopic structure and macroscopic properties of drugs, which reside in their molecular structures. By means of medicinal chemistry the evolution of an active compound to a novel drug (NME) essentially makes the two pillars coexistence in one chemical structure, which either could merge as an intrinsic structure or connect from external fragments to each other with covalent bonds. Since the new millennium the advance in biology provides several knowledge and technologies, for example humanized monoclonal antibody, proteasome-ubiquitin system, allosteric modulation, natural macromolecules, structural biology, etc., for innovation of novel medicines. Taking several examples on marketed drugs or drug candidates in clinical trials, this article tries to concisely illustrate R & D conception of biology-driven drug design.

Research advances on the chemical constituents and pharmacological effects of snow lotus / 药学学报

Snow lotus is a medicinal plant with a wide range of pharmacological activities. It has been used to treat rheumatoid arthritis, cough with cold, stomach ache, dysmenorrhea, and altitude sickness in traditional medicine. This review summarizes the bioactive components in six species of snow lotus including flavonoids, lignans, phenolic compounds, phenylpropanoids, and sesquiterpenes present in Saussurea involucrate (SI), Saussurea obvallata (SO), Saussurea laniceps (SL), Saussurea medusa (SM), Saussurea stella (SS) and Saussurea tridactyla (ST). We review the pharmacological and related molecular mechanisms by which these components exert antineoplastic, anti-inflammatory, and antioxidant effects and promote lipid catabolism, and provide a reference for the future study of the traditional Chinese medicinal chemistry and pharmacological activities of snow lotus.

Research advances in the transformation of chronic obstructive pulmonary disease to lung cancer / 药学学报

The incidence and mortality of chronic obstructive pulmonary disease (COPD) and lung cancer are increasing year by year, which are causing massive social and financial burdens around the world. An increasing number of investigations indicate the possibility of COPD transforming into lung cancer. The pathogenesis of these two diseases have some common aspects, such as epithelial-mesenchymal transition, chronic inflammation, DNA damage, impaired immune system, oxidative stress and tumor angiogenesis, which are heavily complicated. This review summarizes the epidemiological connection between COPD and lung cancer, the molecular-level transformation mechanism as well as the therapeutic strategy. Exploring the transformation mechanism and related signaling pathway of COPD to lung cancer can contribute to block the risk factors for the transformation and provide guidance for the novel drug development and drug therapy.

Non-coding RNA and tumor immune regulation / 药学学报

non-coding RNA (ncRNA) is a kind of non-protein coding RNA, which plays a vital role in the initiation and development of tumor. The immune system also exhibits more complex function in tumor development. It can not only inhibit the development of tumor, but also create conditions for tumor growth. As an important means of tumor therapy, tumor immunotherapy can be regulated by non-coding RNA to achieve the goal of treatment. This article summarizes the regulation of tumor immunity by non-coding RNA.

Investigation into perturbed nucleoside metabolism and cell cycle for elucidating the cytotoxicity effect of resveratrol on human lung adenocarcinoma epithelial cells / 中国天然药物

In an effort to understand the molecular events contributing to the cytotoxicity activity of resveratrol (RSV), we investigated its effects on human lung adenocarcinoma epithelial cell line A549 at different concentrations. Cellular nucleoside metabolic profiling was determined by an established liquid chromatography-mass spectrometry method in A549 cells. RSV resulted in significant decreases and imbalances of deoxyribonucleoside triphosphates (dNTPs) pools suppressing subsequent DNA synthesis. Meanwhile, RSV at high concentration caused significant cell cycle arrest at S phase, in which cells required the highest dNTPs supply than other phases for DNA replication. The inhibition of DNA synthesis thus blocked subsequent progression through S phase in A549 cells, which may partly contribute to the cytotoxicity effect of RSV. However, hydroxyurea (HU), an inhibitor of RNR activity, caused similar dNTPs perturbation but no S phase arrest, finally no cytotoxicity effect. Therefore, we believed that the dual effect of high concentration RSV, including S phase arrest and DNA synthesis inhibition, was required for its cytotoxicity effect on A549 cells. In summary, our results provided important clues to the molecular basis for the anticancer effect of RSV on epithelial cells.

A brief analysis of bifunctional molecules / 药学学报

Selectivity of drug action is a determinant for wide therapeutic window and less adverse response. From the viewpoint of molecular structure the conception and strategy of drug design are mainly embodied in raising selectivity. For the target-based drug discovery it is crucial to precisely obliterate detrimental targets in dimension of time and space, so as to efficaciously translate the in vitro active compounds into in vivo therapeutic medicines. To realize this translation drug molecules must be accurately transported to and destroy the harmful targets. To this end, chemical structures of drugs must be manipulated in multiple dimensions. This article attempts to concisely describe several kinds of bifunctional molecules for raising selectivity from the standpoint of medicinal chemistry. The bifunctionality of antibody-drug conjugates (ADCs) involves in the guidance and carrier of the antibody to guide ADC and reach to target cells, and simultaneously injury quality of the toxin moiety of ADC interacts with and destroys targets. Based upon target 3D structures design of irreversible inhibitors consist in connecting an appropriate electrophilic moiety to a well-defined ligand to endow the molecule with an additional ability to covalently bond to a specific amino acid residue. Hydrophobic tag (HyT), proteosis-targeting chimera (PROTAC), and degradation tag (dTAG) are new developed technologies, which are structurally characterized by bifunctionality, and mechanistically these compounds are capable of recruiting protein of interest (POI), inducing protein-protein interaction (PPI), and cleaving POI. In spite of large molecular size and the bottleneck of pharmacokinetic and physicochemical properties these technologies still have broad development prospect owing to high selectivity and wide adaptations.

On the innovation of follow-on drugs / 药学学报

Follow-on drug approach is to follow-up and make-up of the innovation of pioneering drugs. Since the millennium new molecular entities (NME) have experienced ample optimization, and the patents have claimed in wide ranges, as well as the drug administration requires NME being superior or non-inferior to the existing drugs of the same class. These situations have made the space of follow-on drug innovation narrow and smaller than before. The follow-on drug approach can be concisely differentiated into two aspects:one is to start from the chemistry of small molecules, which are performed with a niche-targeting manipulation to optimize the safety, efficacy and (or) convenience for dose superior to the existing drugs; another proceeds with the macromolecule targets. Based on the knowledge of the mechanism of action or of target mutation, active compounds are constructed through complementary binding or by the reaction mechanism. In this article successful examples are briefly described to illustrate the features of follow-on drug approach.