Triazol: a privileged scaffold for proteolysis targeting chimeras.

Current traditional drugs such as enzyme inhibitors and receptor agonists/antagonists present inherent limitations due to occupancy-driven pharmacology as the mode of action. Proteolysis targeting chimeras (PROTACs) are composed of an E3 ligand, a connecting linker and a target protein ligand, and are an attractive approach to specifically knockdown-targeted proteins utilizing an event-driven mode of action. The length, hydrophilicity and rigidity of connecting linkers play important role in creating a successful PROTAC. Some PROTACs with a triazole linker have displayed promising anticancer activity. This review provides an overview of PROTACs with a triazole scaffold and discusses its structure-activity relationship. Important milestones in the development of PROTACs are addressed and a critical analysis of this drug discovery strategy is also presented.

Epigenetic Modification in Macrophages: A Promising Target for Tumor and Inflammation-associated Disease Therapy.

Macrophages are essential for supporting tissue homeostasis, regulating immune response, and promoting tumor progression. Due to its heterogeneity, macrophages have different phenotypes and functions in various tissues and diseases. It is becoming clear that epigenetic modification playing an essential role in determining the biological behavior of cells. In particular, changes of DNA methylation, histone methylation and acetylation regulated by the corresponding epigenetic enzymes, can directly control macrophages differentiation and change their functions under different conditions. In addition, epigenetic enzymes also have become anti-tumor targets, such as HDAC, LSD1, DNMT, and so on. In this review, we presented an overview of the latest progress in the study of macrophages phenotype and function regulated by epigenetic modifications, including DNA methylation and histone modifications, to better understand how epigenetic modification controls macrophages phenotype and function in inflammation-associated diseases, and the application prospect in anti-tumor.

Identification of novel 1-indolyl acetate-5-nitroimidazole derivatives of combretastatin A-4 as potential tubulin polymerization inhibitors.

Microtubules are essential for the mitotic division of cells and have become an attractive target for anti-tumour drugs due to the increased incidence of cancer and significant mitosis rate of tumour cells. In this study, a total of six indole 1-position modified 1-indolyl acetate-5-nitroimidazole derivatives were designed, synthesized, and evaluated for their ability to inhibit tubulin polymerization caused by binding to the colchicine-binding site of tubulin. Among them, compound 3 displayed the best ability to inhibit tubulin polymerization; it also exhibited better anti-proliferative activities than colchicine against a panel of human cancer cells (with IC50 values ranging from 15 to 40nM), especially HeLa cells (with IC50 values of 15nM), based on the cellular cytotoxicity assay results. Moreover, cellular mechanism studies indicated that compound 3 could induce G2/M phase arrest and apoptosis of HeLa and MCF-7 cells, which were associated with alterations in the expression of cell cycle-checkpoint related proteins (Cyclin B1, Cdc2, and P21) and a reduction in the mitochondrial membrane potential as well as alterations in the levels of apoptosis-related proteins (PARP, Caspase 9, Bcl-2, and Bax) of these cells, respectively. Importantly, in vivo studies further revealed that compound 3 could dramatically suppress HeLa cell xenograft tumour growth compared with vehicle and CA-4 phosphate (CA-4P), and no signs of toxicity were observed in these mice. Collectively, these in vitro and in vivo results indicated that compound 3 might be a promising lead compound for further development as a potential anti-cancer drug.

Recent Developments of Metal and Metal Oxide Nanocatalysts in Organic Synthesis.

Recently, various nanomaterials have been used in many organic transformations as efficient catalysts. The development of new catalysts by nanoscale design has emerged as a fertile field for research and innovation. The ability of nanotechnology to enhance catalytic activity opens the potential to replace expensive catalysts with lower amounts of inexpensive nanocatalysts. Besides, development of efficient and environmentally friendly synthetic methodologies for the synthesis of compound libraries of medicinal scaffolds is an attractive area of research in both academic and pharmaceutical industry. According to above reports and needs, this review deals with applications of nanoparticles as catalysts in various organic syntheses. We detail the topic of organic transformations using nanoparticles: Metal Nanoparticles and Metal Oxide Nanoparticles. In the latter part, different Metal Oxide Nanoparticles, such as ZnO Nanoparticle, TiO2 Nanoparticle, and CuO Nanoparticle are discussed.

Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents.

A series of 12 novel acylhydrazone, chalcone and amide-bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, (1)H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 µM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential.

The complete mitochondrial genome sequence of Garrulax poecilorhynchus (Aves, Passeriformes, Timaliidae).

The entire mitochondrial genome of Garrulax poecilorhynchus consists of 17 814 bp and containe 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two control regions. The nucleotide composition of the mitogenome of G. poecilorhynchus is A = 5342 (29.99%), T = 4314 (24.22%), G = 2480 (13.92%), and C = 5678 (31.87%). The genome has an overall A + T content of 54.21%, which has a similar value among known genus Garrulax mitogenomes. All the tRNA genes display a typical clover-leaf structure. Garrulax poecilorhynchus share the closest relationship with other two species, G. perspicillatus and G. sannio. These data could serve to enrich the resource of genus Garrulax in systematic, population genetic, and evolutionary biological studies.

Evidence of adaptive evolution of alpine pheasants to high-altitude environment from mitogenomic perspective.

Adaptive evolutions to high-altitude adaptation have been intensively studied in mammals. However, considering the additional vertebrate groups, new perception regarding selection challenged by high-altitude stress on mitochondrial genome can be gained. To test this hypothesis, we compiled and analyzed the mitochondrial genomes of 5 alpine pheasants and 12 low-altitude species in Phasianidae. The results that evolutionary rates of ATP6 and ND6 showing significant fluctuation among branches when involved with five alpine pheasants revealed both genes might have implications with adapting to highland environment. The radical physico-chemical property changes identified by the modified MM01 model, including composition (C) and equilibrium constant (ionization of COOH) (Pk') in ATP6 and beta-structure tendencies (Pß), Pk', and long-range non-bonded energy (El) in ND6, suggested that minor overall adjustments in size, protein conformation and relative orientation of reaction interfaces have been optimized to provide the ideal environments for electron transfer, proton translocation and generation of adenosine triphosphate (ATP). Additionally, three unique substitution sites were identified under selection in ND6, which could be potentially important adaptive changes contributing to cellular energy production. Our findings suggested that adaptive evolution may occur in alpine pheasants, which are an important complement to the knowledge of genetic mechanisms against the high-altitude environment in non-mammal animals.

Characteristic of complete mitochondrial genome and phylogenetic relationship of Garrulax sannio (Passeriformes, Timaliidae).

Garrulax sannio (Passeriformes, Timaliidae) was the medium-sized bird, whose plumage color was similar for both sexes. The complete sequence of the mitochondrial DNA genome from G. sannio used the polymerase chain reaction method. The genome (17 840 bp in length) contained 13 protein-coding genes, 2 rRNA (12S and 16S) genes, 22 tRNA genes and 2 control regions (D-loop). The base composition of G. sannio mitogenome A + T percentage was 52.22%. It is slightly higher than G + C 47.78% which was similar with other vertebrates. Through constructed phylogenetic tree, we could identify its taxonomic status. Therefore, mitochondrial genome was a best way to preserve genetic resources of species.

Characterization of the complete mitochondrial genome and phylogenetic relationship of Pomatorhinus ruficollis (Passeriformes, Timaliinae).

In our study, we first report complete mitogenome for P. ruficollis and obtain basic genetic information. The genome of P. ruficollis is 17 009 bp which contained 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and two control regions. Overall bases composition of the complete mitochondrial genome is 29.70%A, 14.47%G, 23.31% T, 32.52%C. Twelve PCGs and 14 tRNA genes are distributed on the H-strand, ND6 and eight tRNA genes are encoded on the L-strand.

Mitochondrial genome of Stachyris ruficeps (Aves, Passeriformes, Timaliidae).

Stachyris ruficeps are commonly found in the eastern Himalayas and south China. In our study, we reported the complete mitogenome and obtain basic genetic information of S. ruficeps for the first time. The complete mitochondrial genomes of S. ruficeps (16 885bp in length) had 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes (12S rRNA and 16S rRNA) and 2 control regions. All of the 13 PCGs were initiated by ATG. All the genes in S. ruficeps were distributed on the H-strand, except for the ND6 gene and eight tRNA genes which were encoded on the L-strand.

Discovery and molecular modeling of novel 1-indolyl acetate--5-nitroimidazole targeting tubulin polymerization as antiproliferative agents.

A series of 18 novel 1-indolyl acetate-5-nitroimidazole 3a-3r were designed, synthesized, and evaluated for their in vitro biological activities as potential tubulin polymerization inhibitors. Among these compounds, 3p displayed strong antitumor activity with IC50 of 2.00, 1.05, 0.87 µM against A549, Hela and U251 respectively, and also showed the most potent PLK1 inhibitory activity with IC50 of 2.4 µM. Molecular docking studies within the colchicine binding site of tubulin were in good agreement with the tubulin polymerization inhibitory data and confirmed the importance of the configuration of the synthesized 1-indolyl acetate-5-nitroimidazolefor potential tubulin polymerization inhibitors.

Genetic diversity and differentiation of the rhesus macaque (Macaca mulatta) population in western Sichuan, China, based on the second exon of the major histocompatibility complex class II DQB (MhcMamu-DQB1) alleles.

BACKGROUND: Rhesus macaques living in western Sichuan, China, have been separated into several isolated populations due to habitat fragmentation. Previous studies based on the neutral or nearly neutral markers (mitochondrial DNA or microsatellites) showed high levels of genetic diversity and moderate genetic differentiation in the Sichuan rhesus macaques. Variation at the major histocompatibility complex (MHC) loci is widely accepted as being maintained by balancing selection, even with a low level of neutral variability in some species. However, in small and isolated or bottlenecked populations, balancing selection may be overwhelmed by genetic drift. To estimate microevolutionary forces acting on the isolated rhesus macaque populations, we examined genetic variation at Mhc-DQB1 loci in 119 wild rhesus macaques from five geographically isolated populations in western Sichuan, China, and compared the levels of MHC variation and differentiation among populations with that previously observed at neutral microsatellite markers. RESULTS: 23 Mamu-DQB1 alleles were identified in 119 rhesus macaques in western Sichuan, China. These macaques exhibited relatively high levels of genetic diversity at Mamu-DQB1. The Hanyuan population presented the highest genetic variation, whereas the Heishui population was the lowest. Analysis of molecular variance (AMOVA) and pairwise FST values showed moderate genetic differentiation occurring among the five populations at the Mhc-DQB1 locus. Non-synonymous substitutions occurred at a higher frequency than synonymous substitutions in the peptide binding region. Levels of MHC variation within rhesus macaque populations are concordant with microsatellite variation. On the phylogenetic tree for the rhesus and crab-eating macaques, extensive allele or allelic lineage sharing is observed between the two species. CONCLUSIONS: Phylogenetic analyses confirm the apparent trans-species model of evolution of the Mhc-DQB1 genes in these macaques. Balancing selection plays an important role in sharing allelic lineages between species, but genetic drift may share balancing selection dominance to maintain MHC diversity. Great divergence at neutral or adaptive markers showed that moderate genetic differentiation had occurred in rhesus macaque populations in western Sichuan, China, due to the habitat fragmentation caused by long-term geographic barriers and human activity. The Heishui population should be paid more attention for its lowest level of genetic diversity and relatively great divergence from others.

Synthesis, biological evaluation, and molecular docking studies of novel 2-styryl-5-nitroimidazole derivatives containing 1,4-benzodioxan moiety as FAK inhibitors with anticancer activity.

A series of 2-styryl-5-nitroimidazole derivatives containing 1,4-benzodioxan moiety (3a-3r) has been designed, synthesized and their biological activities were also evaluated as potential antiproliferation and focal adhesion kinase (FAK) inhibitors. Among all the compounds, 3p showed the most potent activity in vitro which inhibited the growth of A549 with IC50 value of 3.11 µM and Hela with IC50 value of 2.54 µM respectively. Compound 3p also exhibited significant FAK inhibitory activity (IC50=0.45 µM). Docking simulation was performed for compound 3p into the FAK structure active site to determine the probable binding model.

Genetic variation and phylogenetic relationship between three serow species of the genus Capricornis based on the complete mitochondrial DNA control region sequences.

The molecular evidence of phylogenetic status regarding the Formosan serow (Capricornis swinhoei) is not robust and little is known about the genetic diversity of the Sumatran serow (Capricornis sumatraensis), which partly is due to the hardness in sample collection. Here we determined the sequences of the complete mitochondrial DNA control region (1,014 bp) of 19 Sumatran-serow individuals. Nine new haplotypes were defined based on 78 variable sites. Combined analysis with other 32 haplotypes downloaded from the public database, including 1 Sumatran-serow, 11 Formosan-serow and 20 Japanese-serow (Capricornis crispus) haplotypes, a relatively high level of nucleotide diversity was first observed in Sumatran serow (π = 0.0249). By comparative analysis with structural consensus sequences from other mammals, we have identified central, left and right domains and depicted the putative functional structure, including extend termination associated sequences and conserve sequence blocks, in mtDNA control region. The alignment of mtDNA control region revealed that both Sumatran and Japanese serow have two tandem repeats (TRs), but three TRs in Formosan serow. Phylogenetic analyses revealed that the Formosan serow is distinct species with the Japanese serow, but a sister group with the Sumatran serow. The divergence time estimated among three serow species revealed that Pleistocene climate changes and the uplift of Qinghai-Tibetan plateau might play an important role in the genetic differentiation of the serows. These results mainly provide the convinced evidence on the genetic relationship between three serow species.

[Polymorphic analysis of Mhc-DPB1 gene exon 2 in Tibetan macaques (Macaca thibetana)].

Major histocompatibility complex (MHC) molecules play an important role in the susceptibility and/or resistance to many diseases. To gain an insight into the MHC background of the Tibetan macaques (Macaca thibetana), and thereby facilitate their protection and application in biomedical research, the second exon of the Mhc-DPB1 genes from 70 Tibetan macaques in Sichuan Province were characterized by PCR, cloning, sequencing, and statistical analysis. A total of 18 Mhc-DPB1 alleles were identified from Tibetan macaques, of which one (Math-DPB1*01:06N) was a pseudogene. Math-DPB1*06:01:01 (67.14%) was the most frequent allele in all the 18 alleles detected, followed by Math-DPB1* 01:03:01 (37.14%), Math-DPB1*09:02 (25.71%), and Math-DPB1*22:01 (15.71%). The alignment of putative amino acid sequences of the 18 Math-DPB1 alleles showed that 5 variable sites were species-specific to Tibetan macaques. A phylogenetic tree constructed using DPB1 alleles in difference species demonstrated that the alleles for Math-DPB1, Mamu-DPB1, and Mafa-DPB1 tended to mix together, rather than cluster into a separate branch in a species-specific fashion, and the Trans-species polymorphism was also observed in the phylogenetic tree. Selection analysis revealed that balancing selection may play an important role in maintaining the polymorphism of Math-DPB1 genes.

Palmprint and face multi-modal biometric recognition based on SDA-GSVD and its kernelization.

When extracting discriminative features from multimodal data, current methods rarely concern themselves with the data distribution. In this paper, we present an assumption that is consistent with the viewpoint of discrimination, that is, a person's overall biometric data should be regarded as one class in the input space, and his different biometric data can form different Gaussians distributions, i.e., different subclasses. Hence, we propose a novel multimodal feature extraction and recognition approach based on subclass discriminant analysis (SDA). Specifically, one person's different bio-data are treated as different subclasses of one class, and a transformed space is calculated, where the difference among subclasses belonging to different persons is maximized, and the difference within each subclass is minimized. Then, the obtained multimodal features are used for classification. Two solutions are presented to overcome the singularity problem encountered in calculation, which are using PCA preprocessing, and employing the generalized singular value decomposition (GSVD) technique, respectively. Further, we provide nonlinear extensions of SDA based multimodal feature extraction, that is, the feature fusion based on KPCA-SDA and KSDA-GSVD. In KPCA-SDA, we first apply Kernel PCA on each single modal before performing SDA. While in KSDA-GSVD, we directly perform Kernel SDA to fuse multimodal data by applying GSVD to avoid the singular problem. For simplicity two typical types of biometric data are considered in this paper, i.e., palmprint data and face data. Compared with several representative multimodal biometrics recognition methods, experimental results show that our approaches outperform related multimodal recognition methods and KSDA-GSVD achieves the best recognition performance.

Phylogenetic analysis of chinese rhesus macaques (Macaca mulatta) based on mitochondrial control region sequences.

Between one and six subspecies of Chinese rhesus macaques (Macaca mulatta) have been proposed based on morphological differences and/or their geographic distribution. In this study, a 489 base pair fragment of the mitochondrial control region was amplified from 230 DNA samples collected from rhesus macaques in the Sichuan province in Western China. The fragment was then sequenced and aligned with 208 sequences from wild rhesus macaques, sampled throughout the species' geographic range in China downloaded from GenBank. Phylogenetic analysis of the 182 unique sequences identified among these samples divided Chinese rhesus macaques into two western haplogroups (haplogroups A and B) and three older eastern haplogroups (haplogroups C, D, and E), whose differentiation probably occurred during the penultimate glacial event. During the warming after the penultimate glacial event, haplogroups A, B, and E rapidly expanded and a relatively young subhaplogroup of haplogroup E, E', limited to Southern China but shared with Vietnamese rhesus macaques, was reintroduced from Indochina during the last glacial event. One haplotype most closely related to subhaplogroup E' probably represents the isolation of Hainan Island, to where it is restricted, from the mainland by the formation of the Qiongzhou Strait approximately 8,500 years ago. The distribution of haplogroups both informs the phylogeographic history of dispersal of Chinese rhesus macaques and has implications for their suitability as animal models in biomedical research.

[Polymorphism of MHC-DPB1 gene exon 2 in rhesus macaques (Macaca mulatta)].

Rhesus macaque (Macaca mulatta) has long been used as an experimental model animal for biomedical research and was under the key state protection (class II) from Chinese government. In order to facilitate the use of Chinese rhesus macaques in biomedical research and their protection based on better understanding of the major mistocompability complex (MHC) genes in these macaques, the exon 2 of Mamu-DPB1 genes were determined in 106 wild rhesus macaques using DGGE, cloning and sequencing. A total of 21 Mamu-DPB1 alleles were obtained, of which 15 alleles were novel sequences that had not been documented previously. Mamu-DPB1 30 was the most frequent allele in the whole large population comprising all 106 rhesus macaque individuals (0.1120) and in Xiaojin population (0.1120), Mamu-DPB1 04 in Heishui (0.1702), -DPB1 32 in Bazhong (0.1613), -DPB1 30 in Hanyuan (0.1120), and -DPB1 04 in Jiulong (0.1139). The alignment of the amino acids sequences showed that 12 variable sites were species-specific, of which 9 sites occurred in the putative amino acids sequences of the 15 novel Mamu-DPB1 alleles. Trans-species polymorphism was observed on the phylogenetic tree based on the DPB1 alleles of rhesus macaques and cynomolgus (Macaca fascicularis). In addition, these results also demonstrated that significant genetic differentiation has occurred between Chinese and Indian rhesus macaque population.

[Molecular cloning and evolutionary analysis of hog badger bitter taste receptor T2R2 gene].

Recognition of natural bitter toxins through taste is one of the most effective mechanisms of self-safety. An approximate 1 169 bp sequence of the bitter taste receptor T2R2 gene was obtained by PCR and cloning technique from hog badger genomic DNA(GenBank accession number: FJ812727). This sequence contains a complete single exon (without intron) 915 bp in size, which encodes 304 amino acid residues. The isoelectric point (pI) of the protein is 9.76 and its molecular weight is 34.74 kDa. Topology prediction showed that the T2R2 protein contained one N-glycosylation site, one N-myristoylation site, and two potential protein kinase C phosphorylation sites. Additionally, the whole peptide chain was comprised of seven transmembrane helix regions, four extracellular regions, and four intracellular regions. The T2R2 is a hydrophobic protein with a few hydrophilic components. Homology analysis of the T2R2 gene sequences by Clustal W indicated that the cDNA sequence homology of T2R2 gene in hog badger with dog, cat, cattle, horse, chimpanzee, and mouse is 91.4%, 90.6%, 84.4%, 85.4%, 83.8%and 72.1%, respectively, and the homology of amino acid sequence is 85.5%, 85.8%, 74.0%, 77.6%, 75.3% and 61.5%, respectively. The results of nucleotide acid substitution computation and selective test showed that strong purifying selection (functional constraint) occurred between hog badger and the six species, respectively, which mainly existed in the transmembrane regions of T2R2. In addition, the Neighbour-Joining tree of T2R2 gene exons from these seven species is consistent with their species tree, indicating that the T2R2 gene is suitable for constructing molecular phylogenetic tree among different species likewise.

[Clinical results of 46 patients with jaw fractures but delayed management].

46 cases with jaw fractures but delayed management were reviewed, the time, causes of delayed treatment and outcomes were analyzed retrospectively. The delayed time to treatment was between 2 to 12 days. The causes of delay were multiple. All the patients underwent surgical treatment including open reduction and internal fixation. The results showed that 6 patients were treated 2 to 5 days after injury with primary healing. 31 patients were treated 5 to 10 days after injury, 27 were with primary healing. 9 patients were treated 10 to 12 days after injury with primary healing.