Pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base moiety as potential antiviral agents

A series of pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base moiety were synthesized, characterised, and evaluated for their activity against tobacco mosaic virus (TMV). Biological assays indicated that several of the derivatives exhibited significant activity against TMV. In particularly, compounds 5y and 5aa displayed excellent inactivating activity against TMV, with half maximal effective concentration (EC₅₀) values of 70.3 and 53.65?μg/mL, respectively, which were much better than that of ribavirin (150.45?μg/mL), and 5aa was superior to ningnanmycin (EC₅₀?=?55.35?μg/mL). Interactions of compounds 5y and 5aa with TMV coat protein (TMV-CP) were investigated using microscale thermophoresis and molecular docking. Compounds 5y and 5aa displayed strong binding capability to TMV-CP with dissociation constant (K_d) values of 22.6 and 9.8?μM, respectively. These findings indicate that pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base may be potential antiviral agents.     

Hormone interactions to Leu-rich repeats in the gonadotropin receptors. I. Analysis of Leu-rich repeats of human luteinizing hormone/chorionic gonadotropin receptor and follicle-stimulating hormone receptor

The luteinizing hormone receptor (LHR) and follicle-stimulating hormone receptor (FSHR) have an approximately 350-amino acid-long, N-terminal extracellular exodomain. This exodomain binds hormone with high affinity and specificity and contains eight to nine putative Leu-rich repeat (LRR) sequences. LRRs are known to assume the horseshoe structure in ribonuclease inhibitors, and the inner lining of the horseshoe consists of the beta-stranded Leu/Ile-X-Leu/Ile motif. In the case of ribonuclease inhibitors, these beta strands interact with ribonuclease. However, it is unclear whether the putative LRRs of LHR and FSHR play any role in the structure and function. In this work, the beta-stranded Leu/Ile residues in all LRRs of the human LHR and FSHR were Ala-scanned and characterized. In addition, the 23 residues around LRR2 of LHR were Ala-scanned. The results show that beta-stranded Leu and Ile residues in all LRRs are important but not equally. These Leu/Ile-X-Leu/Ile motifs appear to form the hydrophobic core of the LRR loop, crucial for the LRR structure. Interestingly, the hot spots are primarily in the upstream and downstream LRRs of the LHR exodomain, whereas important LRRs spread throughout the FSHR exodomain. This may explain the distinct hormone specificity despite the structural similarity of the two receptors.     

CT诊断用于胰腺癌侵犯胰周动静脉的临床价值分析

目的：探究CT诊断对于胰腺癌侵犯胰周动静脉的临床价值。方法：随机选取在我院就诊的64例胰腺癌患者,在他们进行手术前全在距离肿瘤边缘1cm内的血管进行分期和诊断进而进行螺旋CT检查。结果：经组织学术后病理切片染色发现胰周动脉29条,静脉48条。运用外科手术探查方法发现86条胰周动脉,89条胰周静脉。在这些血管中,有23条动脉、47条静脉经外科手术证实的确是肿瘤侵犯,并且经过CT诊断,我们最终断定为有25条动脉、46条静脉处于1～4级。结论：胰周动、静脉受到侵犯时,具有不同的CT表现特征,因此在利用CT方法判断胰周动、静脉遭受侵犯时应当根据不同情况不同对待。     

Therapeutic potential of α,β‐thujone through metabolic reprogramming and caspase‐dependent apoptosis in ovarian cancer cells

The therapeutic potential of α,β‐thujone, a functional compound found in many medicinal plants of the Cupressaceae, Asteraceae, and Lamiaceae families, has been demonstrated, including in inflammation and cancers. However, its pharmacological functions and mechanisms of action in ovarian cancer remain unclear. We investigated the anticancer properties of α,β‐thujone in ES2 and OV90 human ovarian cancer cells and its effect on sensitization to cisplatin. α,β‐thujone inhibited cancer cell proliferation and induced cell death through caspase‐dependent intrinsic apoptotic pathways. Moreover, α,β‐thujone‐mediated endoplasmic reticulum stress was associated with the loss of mitochondrial functions and altered metabolic landscape of ovarian cancer cells. α,β‐Thujone attenuated blood vessel formation in transgenic zebrafish, implying it has significant antiangiogenic potential. In addition, α,β‐thujone sensitized ovarian cancer cells to cisplatin, causing synergistic pharmacological effects. Collectively, our results suggest that α,β‐thujone has therapeutic potential in human ovarian cancer and functions via regulating multiple intracellular stress‐associated metabolic reprogramming and caspase‐dependent apoptotic pathways.     

HIV-1 TAT-mediated protein transduction and subcellular localization using novel expression vectors

Several novel prokaryotic and eukaryotic expression vectors were constructed for protein transduction and subcellular localization. These vectors employed an N-terminal stretch of 11 basic amino acid residues (47-57) from the human immunodeficiency virus type 1 (HIV-1) TAT protein transduction domain (PTD) for protein translocation and cellular localization. The vectors also contained a six-histidine (His(6)) tag at the N- or C-terminus for convenient purification and detection, and a multiple cloning site for easy insertion of foreign genes. Some heterologous genes including HSV-TK, Bcl-rambo, Smac/DIABLO and GFP were fused in-frame to TAT PTD and successfully overexpressed in Escherichia coli. The purified TAT-GFP fusion protein was able to transduce into the mammalian cells and was found to locate mainly in the cytosol when exogenously added to the cell culture medium. However, using a transfection system, mammalian-expressed TAT-GFP predominantly displayed a nuclear localization and nucleolar accumulation in mammalian cell lines. This discrepancy implies that the exact subcellular localization of transduced protein may depend on cell type, the nature of imported proteins and delivery approach. Taken together, our results demonstrate that a TAT PTD length of 11 amino acids was sufficient to confer protein internalization and its subsequent cellular localization. These novel properties allow these vectors to be useful for studying protein transduction and nuclear import.     

Feasibility of hydrogen production from ripened fruits by a combined two-stage (dark/dark) fermentation system

Anaerobic fermentation for hydrogen (H₂) production was studied in a two-stage fermentation system fed with different ripened fruit feedstocks (apple, pear, and grape). Among the feedstocks, ripened apple was the most efficient substrate for cumulative H₂ production (4463.7 mL-H₂ L⁻¹-culture) with a maximum H₂ yield (2.2 mol H₂ mol⁻¹ glucose) in the first stage at a hydraulic retention time (HRT) of 18 h. The additional cumulative biohydrogen (3337.4 mL-H₂ L⁻¹-culture) was produced in the second stage with the reused residual substrate from the first stage. The major byproducts in this study were butyrate, acetate, and ethanol, and butyrate was dominant among them in all test runs. During the two-stage system, the energy efficiency (H₂ conversion) obtained from mixed ripened fruits (RF) increased from 4.6% (in the first stage) to 15.5% (in the second stage), which indicated the energy efficiency can be improved by combined hydrogen production process. The RF could be used as substrates for biohydrogen fermentation in a two-stage (dark/dark) fermentation system.     

Inhibition of poly(ADP-ribose) polymerase activity by Bcl-2 in association with the ribosomal protein S3a.

We screened a human lymphocyte cDNA library using the yeast two-hybrid system and an automodification domain of PARP as a probe. The DNA sequence of an isolated clone (clone 3-9) was identical to the partial cDNA sequence of the human ribosomal protein S3a. We confirmed that PARP interacts with clone 3-9 by performing binding studies using a GST-3-9 fusion protein as bait. We also demonstrated that native S3a in nuclear extracts of HL-60 cells interacts with the automodification domain of PARP and that PARP from nuclear extracts is coprecipitated with the GST-3-9 fusion protein. Furthermore, we demonstrated that Bcl-2 interacts with PARP in association with S3a and that the interaction of S3a and Bcl-2 with PARP causes a significant decrease in PARP activity. Since Bcl-2 failed to inhibit PARP activity in the absence of S3a, we suggest that Bcl-2 together with S3a prevents apoptosis probably by inhibiting PARP activity.     

Complete genome sequence of the bacterium Ketogulonicigenium vulgare Y25

Ketogulonicigenium vulgare is characterized by the efficient production of 2KGA from L-sorbose. Ketogulonicigenium vulgare Y25 is known as a 2-keto-L-gulonic acid-producing strain in the vitamin C industry. Here we report the finished, annotated genome sequence of Ketogulonicigenium vulgare Y25.