PubMed Health⌕ Search

Biomedical subjects

Weili Zhao

Publications and source records attributed to Weili Zhao.

10 recordsLinked to original sources

Decoding mechanoregulation in immunological synapses using biomimetic artificial cells.

Mechanical force-driven signaling has emerged as a key regulator of cell-cell interactions (CCIs), which can enhance immune cell function. However, current biochemical approaches for studying CCIs offer minimal direct control over cellular bulk phenotypes, while synthetic biomaterial systems fail to mimic the dynamic complexity of cells. Here we introduce kpiCells, a biomaterial-based platform that uses a biomimetic membrane-endoplasmic architecture to enable finely tuned phenocopying of cellular states via modular mechanical, chemical and topographical inputs. We demonstrate that kpiCells can engage in physiological CCIs and reproduce critical subcellular features. In T cell systems, kpiCells enable integrated interrogation of afferent mechanosensing pathways and efferent force-exertion pathways, and support measurement of piconewton-scale forces at individual T cell antigen receptors as well as single cell-cell force fingerprints that define activation thresholds. This work establishes kpiCells as a bionic model that enables synthetic material design with the level of functional complexity approaching living cell systems.

Artificial Cells↗

Oligothiophene-linked bisnaphthopyrans: sequential and temperature-dependent photochromism.

Photochromic bisnaphthopyrans linked with oligothiophenes were synthesized and their photochromic behavior studied. Sequential and temperature-dependent photochromism was observed in the oligothiophene linked bisnaphthopyrans. The kinetics of photo and thermal processes in bisnaphthopyrans in comparison with naphthopyrans were studied. Substituent and linking effects on the photochromic properties are discussed. We demonstrate that the cross-talk between the two photochromophores is dependent on the length of the oligothiophene linker. The presence of the bithiophene linker led to high colorability and high quantum yield of coloration.

Journal Article↗

Conformationally restricted aza-BODIPY: highly fluorescent, stable near-infrared absorbing dyes.

Novel NIR fluorescent, conformational restricted aza-dipyrromethene boron difluoride (aza-BODIPY) dyes were prepared by an efficient process. Such conformational restricted aza-BODIPY dyes possess intense absorption, strong fluorescence, high chemical and photostability. Additionally, the sharp fluorescence of non-amine containing aza-BODIPY dyes is insensitive to solvent polarity.

Aza Compounds↗

Synthesis and photochromism of novel phenylene-linked photochromic bispyrans.

[reaction: see text] Phenylene-linked bisnaphthopyrans were synthesized in good yields via the one-pot reaction of bis-propargyl alcohols with naphthols. Temperature-dependent photochromism in 1,4-phenylene-linked bispyrans leads to up to 60 nm bathochromic shift between the colored species formed at room temperature and at -20 degrees C. Better fatigue resistance and higher colorability was observed in 1,4-phenylene-linked bis-[2H]-naphtho[1,2-b]pyrans by comparison to the 1,3-phenylene linked bis-[2H]-naphtho[1,2-b]pyrans.

Journal Article↗

Solid-phase synthesis of photochromic spiropyrans.

[reaction: see text] A convenient solid-phase synthesis of spiropyrans is described. A succinate linker was employed, which allows base-catalyzed cleavage of the desired photochromophore derivatized with a succinimide. Excellent yields and purities were obtained for the compounds that comprise a library of 23 spiropyrans. Opening of the succinimide ring in spiropyran could be realized under mild conditions.

Journal Article↗

Facile one-pot synthesis of photochromic pyrans.

[reaction: see text]. Photochromic pyrans, including [3H]naphtho[2,1-b]pyrans, [2H]naphtho[1,2-b]pyrans, indeno-fused naphtho[1,2-b]pyrans, and heteroannulated pyrans, were synthesized in excellent yields through a facile one-pot procedure by reaction of propargyl alcohol and naphthol or phenol derivatives in the presence of 5 mol % PPTS and 2 equiv of (MeO)3CH. Symmetrical and nonsymmetrical bispyrans can also be prepared using the protocol.

Journal Article↗

Measurements of the yield and chlorine utilization of singlet oxygen generator by use of Raman spectroscopy.

A Raman scattering system was used to measure the O2 (a1delta) yield end the chlorine utilization in a singlet oxygen generator of chemical oxygen iodine laser with nitrogen diluent. We present the results from the tests that conducted on a 0.1-mol/s jet-type singlet oxygen-iodine generator. On the basis of the current reported uncertainty of the Raman cross section, the error in the yield measurement is calculated to be less than 8%, and the error of the chlorine utilization is 12%.

Journal Article↗

Clinical significance of plasma tissue factor pathway and urokinase-type plasminogen activator system in cancer patients.

OBJECTIVE: To evaluate variations in the plasma tissue factor (TF) and urokinase type plasminogen activator (u-PA) system and their relationship with clinical cancer type, pathological classification and metastatic status in cancer patients. METHODS: Plasma levels of TF and its inhibitor (TFPI), as well as u-PA and its receptor (u-PAR) were measured using ELISA in 76 patients with malignant tumors and 24 patients with benign tumors. RESULTS: Plasma levels of TF and u-PAR in the malignant tumor group were significantly higher than those of the benign tumor group and the normal control. U-PA and u-PAR increased significantly in patients with esophageal and gastric cancer. However, most of these parameters except TFPI did not vary according to pathological classification. A significant elevation was evident in patients with local infiltration, lymph node involvement and distal metastasis, while u-PAR only increased in the latter two categories. CONCLUSIONS: Both the TF and u-PA systems are activated in cancer patients. U-PA and its receptor might prove to be a clinically useful marker for disease progression.

Adult↗