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Kan Zhang

Publications and source records attributed to Kan Zhang.

5 recordsLinked to original sources

A 7-mm Covered TIPS Reduces Hepatic Encephalopathy Without Increasing Rebleeding in Cirrhotic Patients With Small Liver: A Randomized Study.

BACKGROUND/AIMS: International guidelines recommend initiating transjugular intrahepatic portosystemic shunt (TIPS) placement with an 8-mm stent. However, there is an evident lack of randomized controlled trials evaluating TIPS diameters <&#x2009;8&#x2009;mm in cirrhotic patients with a relatively small liver. The aim of this study was to determine whether 7&#x2009;mm-covered TIPS, compared with 8-mm stents, could achieve comparable shunt function with a lower incidence of hepatic encephalopathy (HE). METHODS: In this multicenter randomized controlled trial, patients with cirrhosis and relatively small liver were randomized 1:1 to receive TIPS with a 7-mm (n&#x2009;=&#x2009;92) or 8-mm (n&#x2009;=&#x2009;92) covered stent to prevent variceal rebleeding. The primary endpoint was the incidence of overt HE after randomization. All-cause rebleeding, orthotopic liver transplantation (OLT)-free survival and a composite of these outcomes, were designated as secondary endpoints. RESULTS: Among the 184 enrolled patients, the predominant etiologies of liver cirrhosis were hepatitis B virus infection (56.0%) and alcohol-related liver disease (20.7%). Over a median follow-up of 26.5&#x2009;months, overt HE occurred in 19 patients (20.7%) in the 7-mm group and 33 patients (35.9%) in the 8-mm group. The 2-year cumulative incidence of overt HE was significantly lower in the 7-mm group than in the 8-mm group (21.4% vs. 37.2%, p&#x2009;=&#x2009;0.02). Stent diameter, post-TIPS portosystemic pressure gradient, pre-covert HE and MELD-Na score were identified as independent risk factors for overt HE. The rates of shunt dysfunction were statistically similar between groups (8.7% vs. 8.7%, p&#x2009;=&#x2009;1.0), as were 2-year rebleeding rates (10.9% vs. 9.8%, p&#x2009;=&#x2009;0.81) and OLT-free survival rates (91.3% vs. 88.0%, p&#x2009;=&#x2009;0.82). CONCLUSIONS: A 7-mm covered TIPS demonstrated comparable shunt function to an 8-mm covered stents, with a significantly lower risk of overt HE. These findings support consideration of 7-mm TIPS stents for preventing variceal rebleeding in cirrhotic patients with a small liver who are undergoing TIPS. TRAIL REGISTRATION: ClinicalTrials.gov, NCT02541825.

Humans↗

[Urban greenbelt eco-service value of Hangzhou City under effects of land use change: an evaluation with CITYgreen model].

Based on the Landset TM information of land use/cover change and greenbelt distribution in Hangzhou city in 1994 and 2004, and by using CITYgreen model, this paper estimated the eco-service value of urban greenbelt in the city under the effects of land use change and economic development. The results showed that in the 10 years from 1994 to 2004, the greenbelt area in the city decreased by 20. 4% , while its eco-service value increased by 168 million yuan. The annual increment of greenbelt eco-service value and GDP was 111.92% and 5. 32% , respectively. Suitable adjustment of land use pattern in the city harmonized the relationships between urban economic development and urban eco-function, and achieved higher eco-service efficiency of land utilization.

China↗

Connectivity exploration with structural equation modeling: an fMRI study of bimanual motor coordination.

The present fMRI study explores the connectivity among motor areas in a bimanual coordination task using the analysis framework of structural equation modeling (SEM). During bimanual finger tapping at different frequency ratios, temporal correlations of activations between left/right primary motor cortices (MI), left/right PMdc (caudal dorsal premotor area) and supplementary motor cortex (SMA) were detected and used as inputs to the SEM analysis. SEM was extended from its traditional role as a confirmatory analysis to be used as an exploratory technique to determine the most statistically significant connectivity model given a set of cortical areas based on anatomic constraints. The resultant network exhibits coupling from left MI to right MI, links from both PMs to the two MIs, a negative interaction from left PM to right PM, and functional influence from SMA to right MI and right PM, revealing contributions of these areas to bimanual coordination.

Adolescent↗

Frames of reference in spatial memories acquired from language.

Four experiments examined reference systems in spatial memories acquired from language. Participants read narratives that located 4 objects in canonical (front, back, left, right) or noncanonical (left front, right front, left back, right back) positions around them. Participants' focus of attention was first set on each of the 4 objects, and then they were asked to report the name of the object at the location indicated by a direction word or an iconic arrow. The results indicated that spatial memories were represented in terms of intrinsic (object-to-object) reference systems, which were selected using egocentric cues (e.g., alignment with body axes). Results also indicated that linguistic direction cues were comprehended in terms of egocentric reference systems, whereas iconic arrows were not.

Cues↗

Glycine protection of PC-12 cells against injury by ATP-depletion.

A distinctive mechanism of cell injury during ATP depletion involves the loss of cellular glycine. The current study examined whether provision of glycine during ATP depletion can prevent injury in PC-12 cells, a cell line with neuronal property. In addition, we have examined the role played by glycine receptors in cytoprotective effects of the amino acid. It was shown that ATP depletion led to plasma membrane damage in PC-12 cells, which was ameliorated by 0.25-5 mM glycine. Cytoprotective activity of glycine was shared by alanine, but not by glutamate or gamma-aminobutyric acid (GABA). Of interest, strychnine, an antagonist of glycine receptor, was also protective. The results, while suggesting the involvement of glycine receptor in cytoprotection, indicate that chloride channel activity of the receptor is dispensable. Such a scenario is further supported by the observation that removal of extracellular chloride did not affect ATP depletion-induced cell injury or its prevention by glycine. In short, this study has provided the first evidence for glycine protection of cells with neuronal properties. Cytoprotection may involve the glycine receptor; however, it can be dissociated from its channel activity.

Adenosine Triphosphate↗