BACKGROUND:At present,traditional drug delivery routes(oral or intravenous injection)in clinical practice face the problem of difficulty in penetrating the blood-brain barrier,and the clinical treatment of open severe traumatic brain injury is often lower than expected.Hydrogels are a class of extremely hydrophilic three-dimensional network structure gels,which swell rapidly in water and can be maintained in the swelling state.Hydrogels swell rapidly in water and can remain in this swollen state.At present,some experimental studies have applied injectable functional hydrogel injection into the injured site to achieve the purpose of repairing damaged brain tissue,but this treatment strategy has not been applied in clinic.OBJECTIVE:To analyze the role of functional hydrogels in tissue repair after traumatic brain injury,discuss the promotion of nerve tissue regeneration after traumatic brain injury through different action modes,so as to propose new ideas for clinical treatment and basic research of traumatic brain injury.METHODS:English key words"hydrogels,functional hydrogel,composite hydrogels,traumatic brain injury,tissue repair,neural regeneration"and Chinese key words"functional hydrogels,traumatic brain injury,tissue repair,nerve regeneration"were used to search the relevant articles published from August 2000 to March 2024 in PubMed,Web of Science,CNKI,and WanFang databases.The inclusion and exclusion criteria were formulated,and 60 relevant articles were finally included after being screened by reading the title,abstract,and full text of articles.RESULTS AND CONCLUSION:(1)The hydrogel based on molecular design can simulate the neural microstructure,promote regeneration and repair,and simulate the neurovascular unit to promote vascular regeneration.(2)Hydrogels based on the principle of combined drug therapy can deliver endogenous neuroregulatory factors,coating drugs to promote nerve regeneration.(3)Hydrogels based on stem cell recovery strategies can be used as molecular scaffolds to deliver cell therapy.(4)Future researchers need to further explore functional hydrogels related to nerve tissue repair to provide effective strategies for therapeutic function reconstruction in traumatic brain injury patients.

BACKGROUND:At present,traditional drug delivery routes(oral or intravenous injection)in clinical practice face the problem of difficulty in penetrating the blood-brain barrier,and the clinical treatment of open severe traumatic brain injury is often lower than expected.Hydrogels are a class of extremely hydrophilic three-dimensional network structure gels,which swell rapidly in water and can be maintained in the swelling state.Hydrogels swell rapidly in water and can remain in this swollen state.At present,some experimental studies have applied injectable functional hydrogel injection into the injured site to achieve the purpose of repairing damaged brain tissue,but this treatment strategy has not been applied in clinic.OBJECTIVE:To analyze the role of functional hydrogels in tissue repair after traumatic brain injury,discuss the promotion of nerve tissue regeneration after traumatic brain injury through different action modes,so as to propose new ideas for clinical treatment and basic research of traumatic brain injury.METHODS:English key words"hydrogels,functional hydrogel,composite hydrogels,traumatic brain injury,tissue repair,neural regeneration"and Chinese key words"functional hydrogels,traumatic brain injury,tissue repair,nerve regeneration"were used to search the relevant articles published from August 2000 to March 2024 in PubMed,Web of Science,CNKI,and WanFang databases.The inclusion and exclusion criteria were formulated,and 60 relevant articles were finally included after being screened by reading the title,abstract,and full text of articles.RESULTS AND CONCLUSION:(1)The hydrogel based on molecular design can simulate the neural microstructure,promote regeneration and repair,and simulate the neurovascular unit to promote vascular regeneration.(2)Hydrogels based on the principle of combined drug therapy can deliver endogenous neuroregulatory factors,coating drugs to promote nerve regeneration.(3)Hydrogels based on stem cell recovery strategies can be used as molecular scaffolds to deliver cell therapy.(4)Future researchers need to further explore functional hydrogels related to nerve tissue repair to provide effective strategies for therapeutic function reconstruction in traumatic brain injury patients.

Objective:To explore the correlation between portal vein pressure gradient (PPG) and hepatic vein pressure gradient (HVPG) in patients with portal hypertension (PHT).Methods:752 cases with portal hypertension (PHT) who underwent transjugular intrahepatic portosystemic shunt (TIPS) and met the enrollment criteria between January 2016 to December 2019 were analyzed for hepatic vein, inferior vena cava and portal vein pressure. Paired t-test was used for analysis. Pearson correlation test was used to estimate correlation coefficient and coefficient of determination. P<0.05 were considered statistically significant. Results:Wedged hepatic vein pressure (WHVP), portal vein pressure (PVP), correlation coefficient, and coefficient of determination were 27.98±8.95 mmHg, 33.85±7.33 mmHg, 0.329 ( P<0.001), and 0.108, respectively. HVPG, PPG,correlation coefficient, and coefficient of determination were 16.84±7.97 mmHg, 25.11±6.95 mmHg ( P<0.001), 0.145, and 0.021 ( P<0.001), respectively. The difference between HVPG and PPG was greater than 5 mmHg in 524 cases, accounting for 69.7%. The difference between HVPG and PPG was within 5 mmHg or basically equal in 228 cases, accounting for 30.3%. The correlation coefficient between free hepatic venous pressure (FHVP) and inferior vena cava pressure (IVCP) was 0.568 ( P<0.001), and the coefficient of determination was 0.323. According to the presence or absence of hepatic venous collaterals after balloon occluded hepatic angiography, they were divided into two groups: 157 (20.9%) cases in the group with hepatic venous collaterals, and 595 (79.1%) cases in the group without hepatic venous collaterals. The parameters of the two groups were compared: WHVP (15.73±3.63) mmHg vs. (31.22±6.90) mmHg, P<0.001; PVP (31.69±8.70) mmHg vs. (34.42±6.81) mmHg, P<0.001; HVPG (7.18±4.40) mmHg vs. (19.40±6.62) mmHg, P<0.001; PPG (24.24±8.11) mmHg vs. (25.34±6.60) mmHg, P<0.001; free hepatic venous pressure (FHVP) (8.58±3.37) mmHg vs. (11.82±5.07) mmHg , P<0.001; inferior vena cava pressure (IVCP) (7.45±3.29) mmHg vs. (9.09±4.14) mmHg, P<0.001. Conclusion:The overall correlation is poor between HVPG and PPG. HVPG of most patients is not an accurate representation of PPG, and the former is lower than the latter. Hepatic venous collateral formation is one of the important reasons for the serious underestimation of HVPG values.

Objective:By using balloon occlusive hepatic angiography in cirrhotic portal hypertension to evaluate contrast doses on the detection rate of intrahepatic venous-lateral branch shunt (HVVC), and the effect on hepatic venous pressure gradient (HVPG) and portal vein pressure gradient (PPG).Methods:From Jan 2018 to Jun 2021, 131 patients received transjugular intrahepatic portosystemic shunt (TIPS) at Beijing Shijitan Hospital.Results:A positive correlation between PVP and weged hepatic venous pressure (WHVP) ( r=0.241, P=0.001) was found when only by right hepatic vein approach. Ten ml of iodine contrast medium when compared to 5ml doses found more cases of intrahepatic venous-venous lateral branch shunt. The mean PPG of patients with HVVC was significantly higher than the mean of HVPG( P<0.05).The right hepatic vein was the only reliable vein by which WHVP was measured. Conclusions:Right hepatic vein manometry,adequate ballon occlusion and using 10ml of iodine contrast help get reliable WHVP and found HVVC; HVVC can affect the consistency of HVPG and PPG.