Efficacy and safety of stellate ganglion block with different volumes of ropivacaine to improve sleep quality in patients with insomnia: a comparative study.

OBJECTIVE: The aim of this study was to compare the efficacy and safety of ultrasound-guided stellate ganglion block (SGB) with different volumes of 0.375% ropivacaine on sleep quality in patients with insomnia. PATIENTS AND METHODS: A total of 80 patients who were selected to undergo SGB for the treatment of insomnia were enrolled. The patients were divided into saline control group, and low-volume (4 mL), medium-volume (6 mL), and high-volume (8 mL) ropivacaine injection groups according to the random table method. The treatment included 7 blocks with once every three days. The left and right stellate ganglions are alternately blocked. The onset and maintenance time of Horner syndrome, the degree of carotid artery dilation and blood flow velocity before and 20 minutes after the first block, the occurrence of complications such as drug crossing of the midline of the artery and hoarse throat were recorded, and the improvement of sleep disorders was evaluated with the Pittsburgh Sleep Quality Index Scale. RESULTS: Horner syndrome occurred in 100% of all volumes of ropivacaine block. The ipsilateral internal carotid artery was dilated and was accompanied by increased blood flow. The degree of dilation and increase in blood flow were not affected by the volumes of drug injection. There were no serious complications in any group, but the incidences of hoarseness and dysphagia were higher in the medium- and high-volume groups than those in the low-volume group (all p < 0.05). Compared with the low- and medium-volume groups, the high-volume group had a faster onset of action, longer maintenance time, and the highest chance of the drug crossing the artery (all p < 0.05). Compared to those before the pre-block and in the control groups, insomnia was improved in all volume groups after the block with nonsignificant intergroup differences. CONCLUSIONS: 4 mL of 0.375% ropivacaine for ultrasound-guided SGB is sufficient to improve the sleep quality of insomnia patients, whose overall risk is lower than block with 6 mL or 8 mL of ropivacaine.

[An in vitro study of zinc-alpha-2-glycoprotein inhibits activation and proliferation of hepatic stellate cells].

Objective: To investigate the mechanism of occurrence and development of zinc-alpha-2-glycoprotein (AZGP1) in the activated hepatic stellate cells (HSCs) and liver fibrosis. Methods: The activated human hepatic stellate cell line LX2 was induced by the stimulation of transforming growth factor - ß1 to construct carbon tetrachloride liver fibrosis mice model. The situation expression of AZGP1 in liver cells and tissues were observed. Plasmid transfection method was used to detect the activation, proliferation, apoptotic functions and changes in related factors of LX2 cells, respectively, after the overexpression and inhibition of AZGP1expression. Univariate analysis of variance was used for multiple group comparison. Results: The results of immunofluorescence staining showed that AZGP1 protein was decreased and α-smooth muscle actin was increased in the activated LX2 cells, and the two were negatively correlated. AZGP1 gene and protein were significantly under-expressed in activated LX2 cells and liver tissues of mice with carbon tetrachloride liver fibrosis. Collagen I, matrix metalloproteinase-2, and α-smooth muscle actin genes and proteins were significantly down-regulated in LX2 cells after over-expression of AZGP1. Cell fluorescence showed that AZGP1-overexpressing cells were activated and α-smooth muscle actin protein was reduced. In addition, the proliferative activity and G1/S-specific cyclin D1 protein of LX2 cells were significantly reduced after overexpression of AZGP1, while cell cycle experiments showed that the proportion of cells overexpressing AZGP1 was significantly increased in the G0/G1 phase, and the proportion of S phase was significantly reduced. AZGP1 had no significant effect on the apoptosis of LX2 cells. Conclusion: AZGP1 can reverse liver fibrosis by inhibiting the activation and proliferation of hepatic stellate cells, and thereby overexpression of AZGP1 is expected to become a new target for liver fibrosis treatment.

The membrane-proximal intermolecular disulfide bonds in glycoprotein Ib influence receptor binding to von Willebrand factor.

BACKGROUND: In the platelet glycoprotein (GP)Ib-IX complex, the binding site for its ligand von Willebrand factor (VWF) is restricted to the N-terminal domain of the GPIbalpha subunit. How the other subunits in the complex, GPIbbeta and GPIX, regulate the GPIbalpha-VWF interaction is not clear. OBJECTIVES AND METHODS: As GPIbalpha connects with two GPIbbeta subunits via disulfide bonds, we tested whether these intersubunit covalent links were important to the proper VWF-binding activity of the GPIb-IX complex by characterizing the structure and VWF-binding activity of a mutant GPIb-IX complex that lacked the GPIbalpha-GPIbbeta disulfide bonds. RESULTS: Mutating both Cys484 and Cys485 of GPIbalpha to serine prevents GPIbalpha from forming covalent disulfide bonds with GPIbbeta, while maintaining the integrity of the complex in the membrane. The mutations cause two GPIbbeta subunits to form a disulfide bond between themselves. As compared to Chinese hamster ovary (CHO) cells stably expressing the wild-type GPIb-IX complex at a comparable level, CHO cells stably expressing the mutant GPIb-IX complex bind to significantly less soluble VWF in the presence of ristocetin and roll on the immobilized VWF under flow at a higher velocity. CONCLUSIONS: The disulfide bonds between GPIbalpha and GPIbbeta are necessary for optimal GPIbalpha binding to VWF. The structural plasticity around the disulfide bonds may also help to shed light on the inside-out mechanism underlying GPIbbeta modulation of VWF binding.

Role of the transmembrane domain of glycoprotein IX in assembly of the glycoprotein Ib-IX complex.

BACKGROUND: The glycoprotein (GP) Ib-IX complex is critically involved in platelet adhesion to von Willebrand factor and in the initial step of platelet activation. How this complex is assembled is not clear. We previously showed that the transmembrane (TM) domains of the GPIbalpha and GPIbbeta subunits interact and participate in complex assembly. OBJECTIVES AND METHODS: Here, we have investigated the role of the TM and cytoplasmic domains of GPIX in assembly of the GPIb-IX complex, by analyzing the mutational effects on complex expression and assembly in transiently transfected Chinese hamster ovary cells. RESULTS: Replacing the cytoplasmic domain of GPIX with a poly-alanine sequence had little effect on surface expression and structural integrity of the GPIb-IX complex. In contrast, replacing the GPIX TM domain (residues 132-153) with a poly-leucine-alanine sequence markedly disrupted complex formation of GPIX with GPIbalpha, interfered with GPIb formation, and decreased surface expression of the host complex. We further analyzed the contributions of a number of GPIX TM residues to complex formation by mutagenesis and found significant roles for Asp135 and several Leu residues. CONCLUSIONS: The TM domain, rather than the cytoplasmic domain, of GPIX plays an important role in expression and assembly of the GPIb-IX complex by interacting with its counterparts of GPIb. These TM domains may form a parallel four-helical bundle structure in the complex.

[Determination of tetramethylpyrazine in animal serum and cerebrospinal fluid by high performance liquid chromatography].

A reversed-phase high performance liquid chromatographic (RP-HPLC) method for the determination of the tetramethylpyrazine(TMP) in Chuanxiong extract, the animal(mouse) serum and cerebrospinal fluid has been developed. The TMP was separated on an ODS column Zorbax SB-C18(4.6 mm i.d. x 250 mm, 5 microns) at room temperature and detected by using UV detector at 270 nm. The mobile phase was methanol-water (50:50, V/V) containing 0.2 mmol/L of NH4H2PO4 flowing at a rate of 0.8 mL/min and 20 microL samples were injected. The detection limit of TMP was 1 mg/L and the calibration curve is linear between 5 and 500 mg/L with a correlation coefficient (r) of 0.999. The recovery of TMP ranged 98%-103%. The extract of Chuanxiong and pretreated serum and cerebrospinal fluid sample are stable for a week at room temperature.