BACKGROUND:Numerical stimulation technology is a good method to analyze blood flow changes after intracranial aneurysm stenting that oftenresult in restenosis.
OBJECTIVE:To explore the hemodynamic effect of stent implantation on patient-specific intracranial aneurysm and the distribution of the wal shear stress on the stent surface.
METHODS:Brain CT data from a patient with intracranial aneurysm were extracted and optimized to establish a patient-specific intracranial aneurysm materialization model. Meanwhile, a three-dimensional model of rectangular section spiral stent was designed to develop an aneurysm model with the stent by the method of boolean operation. Then, the possibility of restenosis was analyzed based on the distribution of wal shear stress on the surface of stent model.
RESULTS AND CONCLUSION:The wal shear stress on the stent surface which was more than 40 Pa increasedalong with the increase of blood velocity and blood viscosity at the same moment. However, the wal shear stress on the stent surface which was less than 0.5 Pa decreased along with the increase of blood viscosity, and its distribution was the largest when the blood velocity was 0. This stent provides a new insight into the controling of the aneurysm growth and rupture, but the restenosis area is too large. In order to prevent restenosis, the stent need to be optimized or reselected to keep the desired shear stress values of 0.5 to 40 Pa, and meanwhile to minimize the pulsating change of wal shear stress during a cardiac cycle.

Objective To explore the caring ability and demands of the primary caregivers of stroke patients in community. Methods Seventeen patients of stroke in community participated in the semi-structure interviews. Data were analyzed by Colaizzi phenomenological procedure. Results The lack of ability of the primary caregivers to take care of, mainly reflected inthe lack of professional knowledge of the disease, lack of basic skills and medication blindness. The factors that affected the ability of the primary caregiversto take care ofwere health status and psychological status of the caregivers, duration of illness of patients, coordination degree of patients and financial burden. The caring demands of the caregivers mainly focused on the following areas: professional medical support, economic support, daily care service, and spiritual support services. Conclusions The government and community health service centers should pay more attention tothe rehabilitation of stroke patients in community, and help them to solvepractical problemsactively, meet the care needs, and improve their self-care ability, so as to improve the ability of daily life and quality of life of patients.

Objective To study the placental vascular distribution of monochorionic (MC) twins with twin-to-twin transfusion syndrome (TTTS) or hirth weight discordance.Methods Twenty-eight MC placentas were injected in Peking University Third Hospital between Feb.2010 and Feb.2011.The vascular distribution type (parallel,crossed,mixed and monoamniotic),the anastomosis of vessels and the placental sharing were recorded.The outcome of pregnancy and the placental characteristics of birth weight discordance (birth weight discordance ≥ 20％) in non-TTTS MC twins were analyzed.Results (1) The outcome of pregnancy:the miscarriage or gestational weeks of 28 MC twins were 20 to 38 weeks (median of 35 weeks).Six cases were TTTS,3 of which received fetoscopic laser occlusion of communicating vessels (FLOC).There were 48 live births,with an average birth weight of (2036 ± 623) g.(2) Type of placental vascular distribution:in the 28 MC placentas,number of parallel,crossed,mixed and monoamniotic type of placental vascular distribution were 4 (14％),14 (50％),6 (21％) and 4 (14％) cases,respectively.No parallel type was found in TTTS.There was no significant difference of vascular anastomosis or unequal placental sharing among the different placental vascular distribution types (P ＞ 0.05).(3) Characteristics of placental vascular distribution in birth weight discordance twins:there were 20 non-TTTS MC twin pregnancies,all of which got live births of both babies.Birth weight discordance equal to or more than 20％ was found in 6 pairs of newborns,while birth weight discordance less than 20％ was found in the rest 14 cases.Ratio of unequal placental sharing was significantly different between the two groups (P ＜ 0.01).There was no significant difference of umbilical cord insertion,placental vascular distribution and anastomosis in the two groups (P ＞0.01).Conclusions Vascular distribution type of MC twins might be related to TTTS.Unequal placental sharing is a risk factor of birth weight discordance in non-TTTS MC twins.

Objective To evaluate the relationship between stenosis of intra- or extra-cranial cerebral large artery and capsular warning syndrome(CWS). Methods Eleven consecutive CWS patients hospitalized during period of time from November 2008 to December 2009 were retrospectively analyzed.Result In these 11 patients with CWS, 5 patients had motor symptoms only, 4 patients had pure sensory symptoms, and 2 patients had sensorimotor symptoms. Ten patients underwent cervical contrast-enhanced MRA and intracranial MRA examination. The results showed no sign of arterial stenosis. Seven CWS patients eventually had strokes, 1 progressed to stroke despite receiving the therapy of antiplatelet and anticoagulation. All stroke lesions were located in the capsula interna. All the CWS patients had vascular risks: 7 were smoker, 8 had hypertension, 1 had diabetes mellitus, and 5 had hyperlipidemia. One patient had a history of previous stroke; no patient had a history of ischemic heart disease or atrial fibrillation. At follow-up(10. 2 ±3.4)mouths, the average modified Rankin scale score for all patients was 0. 73 ± 1.20.Conclusion CWS was not associated with stenosis of the intra and extra-cranial large cerebral arteries.CWS may be associated with small-vessel single-penetrator disease.

AIM:This study continuously monitors the hemodynamic changes in conscious and anesthetic rats during rapid ascent to high altitude to investigate whether there is difference between the 2 conditions and discuss the rela-ted underlying mechanism.METHODS: Sprague-Dawley rats were randomly divided into conscious group, anesthetic group, anesthetic-5000-control ( A-5000-control) group, anesthetic-5000-aminoguanidine ( A-5000-AG) group, conscious-5000-control ( C-5000-control ) group and conscious-5000-aminoguanidine ( C-5000-AG ) group.The rats in anesthetic group and conscious group were kept in a hypobaric chamber, in which the simulated altitude was increased from 2 260 m to 5 000 m at 2 m/s, and the rats in other 4 groups were at 5 000 m.The system arterial pressure ( Psa) , central venous pressure ( CVP) , heart rate ( HR) and breathing rate ( BR) were directly and continuously displayed and digitally recorded by a high-performance data acquisition (PowerLab 16/35, AD Instruments) at 200 Hz.RESULTS: The HR and BR in the conscious rats were higher and MAP was lower than those in the anesthetic rats obviously.A significant decrease in mean arterial pressure ( MAP) in conscious and anesthetic groups was observed following the increase in the altitude levels, and the net decrease in MAP in conscious group was significantly greater.Additionally, HR in the conscious rats was sig-nificantly lower at 5 000 m than that of the initial level.The rats in C-5000-AG group and A-5000-AG group showed a sig-nificant increase in the arterial pressure after the intravenous injection of AG, a selective inhibitor of inducible nitric oxide synthase ( iNOS) , and no marked change of HR and BR was found.CONCLUSION: Blood pressure and HR decrease during rapid ascent to high altitude, while the change of BR is not obvious.The mechanisms of self-safety would be trig-gered in the early stage of hypoxia, which activates iNOS and then leads to a larger number of nitric oxide.Plentiful NO di-astolizes the vessels to improve the ventilation-perfusion mismatch and lower the blood pressure.When the altitude arise to 5 000 m, even more earlier, a decompensatory stage may occur in the body, leading to decreased HR and blood pressure further more than those in the anesthetic rats.Due to the effects of pentobarbital sodium, the depression of blood pressure requires a lag period and the net decrease in MAP is less than that in the conscious rats.Therefore, hemodynamic changes during rapid ascent to high altitude in conscious rats are more comprehensive and authentic.

AIM:To investigate the effects of seipin gene deficiency on renal injury and the possible mecha-nisms in seipin-/-mice.METHODS:Six-month-old male seipin knockout ( seipin-/-) and wild-type ( WT) mice ( n=8) were used to study 24 h urinary albumin excretion ( UAE) , renal functions, pathological changes, and plasma leptin and adiponectin levels.Seipin mRNA expression in different tissues and each part of the kidney was also measured in WT mice.RESULTS:Real-time PCR analysis showed seipin mRNA expression in WT mice was higher in adipose tissue and testicles, and was also found in the kidney, which was mainly in glomeruli.Compared with control group, seipin-/-group showed increased kidney weight/tibia length (P<0.01), 24 h UAE (P<0.01), creatinine clearance (P<0.01), and glomerular and mesangial surface area (P<0.05).Both plasma leptin (P<0.01) and adiponectin (P<0.05) levels were significantly decreased in seipin-/-mice.CONCLUSION:Seipin gene deficiency in mice leads to renal injury prob-ably by decreasing plasma leptin and adiponectin levels due to lack of adipose tissue.

Objective:To summarize the ultrasound characteristics of incarceration of gravid uterus (IGU) for improving the diagnostic accuracy of IGU.Methods:Three cases of IGU patients were diagnosed in Peking University Third Hospital from May 2018 to May 2020. CNKI, Wanfang Data, China Science and Technology Journal Database and PubMed were searched using the search terms "incarcerate uterus" or "uterine incarceration" and "gravid" through January 2000 to July 2020, 53 IGU cases were found. The ultrasound data and outcomes of the 56 IGU patients were retrospectively analyzed. The display rate of various ultrasonic features were counted. Relevant literatures were reviewed and the experience were summarized.Results:Of the 56 cases with IGU, 45 cases (80.4%) had positive results, of which 34 cases (60.7%) were found abnormal cervix(elongated anteriorly and superiorly displaced cervix or poorly visualized cervix), 27 cases (48.2%) were found retroversion of the gravid uterus, 12 cases (21.4%) were found that the fundus of the uterus lay deeply in the Douglas pouch, 4 cases (7.1%) were found anteriorly and superiorly displaced bladder. There was statistically significant difference between the displaying rates of abnormal cervix and retroversion of the gravid uterus(χ 2=5.452, P<0.05). Conclusions:Abnormal cervix was the most common feature of IGU by ultrasound. Correct identification of the cervix is helpful to improve the detection rate of IGU.

To determine the inhibition of IL-13 by recombinant sIL-13Rα2 in NIH-3T3 fibroblast cells for its potential therapeutic value in hepatic fibrosis caused by Schistosoma japanicum in mice . IL-13 and sIL-13Rα2 from liver of BALB/c mice infected with S.japonicum at different infection time (weeks 0,6,8,10 and 12) were analyzed by ELISA and RT-PCR. The recombinant sIL-13Rα2 expression plasmidwas constructed, followed by transfection into NIH-3T3 fibroblast cells. TypeⅠcollagen produced by NIH-3T3 cells were examined by RT-PCR and Western blotting. It was demonstrated that the expression of IL-13 increased gradually after infection, reached peak density (16.1586 pg/mL)at week 8 and then reduced but was still higher than the level of control mice(3.4146 pg/mL;P =0.017 ). The secretion of sIL-13R α2 reached to its peak 10 weeks after infection(4827.426 pg/mL)and then reduced slowly but still higher than normal(4057.112 pg/mL; P=0.021). Meanwhile, the changes in mRNA level of IL-13 and sIL-13R α2 were coincided with that examined by ELISA. Both IL-13 and sIL-13Rα2 reached their peak density (P=0.033) at week 8 and 10 (P=0.025) respectively, and they were followed by a slower degree of decrease. The sIL-13Rα2 could significantly inhibit the effect of IL-13 on NIH-3T3 fibroblast cells, showing decreased mRNA level(P =0.012)and protein level of typeⅠcollagen compared with normal groups(P =0.031). It is concluded that the sIL-13Rα2 can inhibit the effect of IL-13 on NIH-3T3 fibroblast cells which leads to a reduced production of typeⅠcollagen, demonstrating its potential therapeutic value in hepatic fibrosis of schistosomiasis.

Objective To investigate the features of the auditory mismatch response (MMR) elicited from the preschoolers and adults.Methods 9 preschoolers aged 3-6 and 8 adults were elicited and measured MMR to speech sounds (/bal/, /pal/) using the Oddball paradigm.Results The response was typical mismatch negativity in adults, and was slow positive waves with larger amplitude in the preschoolers.MNOVA results showed that there were significantly differences between the 2 groups, said the latency of MMRs was significantly longer and the amplitude was larger in the preschoolers than in the adults (P<0.05). Conclusion Stable MMRs with distinct characters in preschoolers and adults have been obtained respectively.

Objective:To evaluate the outcome of laser coagulation under fetoscope for placental chorioangioma (CA).Methods:The clinical data of three pregnant women with giant CA treated by laser coagulation under fetoscope in Peking University Third Hospital from January 2018 to December 2020 were analyzed retrospectively. Relevant articles up to September 2022 were retrieved from Wanfang Database, China National Knowledge Infrastructure and PubMed, and the clinical data of all patients were retrospectively summarized. Indications and intervention effects of fetoscopic laser therapy were analyzed. Descriptive statistics was used to describe the data.Results:Thirteen patients were involved in this study including 10 cases retrieved from the databases. The average age of the pregnant women was (30.3±6.2) years old. There were 12 cases of single pregnancy and one case of twin pregnancy (monochorionic diamnionic twin pregnancy). Except for cases for which data were not available in the literatures, at the diagnosis of CA, the average gestational age was (19.9±4.5) weeks ( n=7) and the average maximum diameter of the mass was (6.1±4.1) cm ( n=6). The patients underwent fetoscopic laser therapy at an average gestational age of (25.0±2.0) weeks ( n=13) with the average maximum tumor diameter of (7.6±2.8) cm ( n=9). After treatment, the amniotic fluid volume of three cases decreased to normal. In one case, the amniotic fluid volume decreased but was still above the upper limit of the normal range. Moreover, the maximum tumor diameter decreased in four cases; the peak systolic velocity of the fetal middle cerebral artery decreased to normal in one case; fetal heart function became normal in two cases and fetal edema was relieved in one case. Among the three patients treated in our hospital, the blood supply of CA disappeared after treatment. Intrauterine fetal death occurred in two cases. The other 11 patients gave birth to live babies at the gestational age of (36.6±3.8) weeks with five through cesarean section (5/11), five through vaginal delivery (4/11) and two not reported. The birth weight of the neonates was (2 712±1 023) g and all of them survived. The gender of five neonates were reported and all were females, two of them were monochorionic diamnionic twins. No abnormality was found in the three neonates delivered in our hospital during a six-month follow-up. No abnormality was reported in the other neonates during ten days to six months of follow-up. Conclusions:Fetoscopic laser coagulation may help reduce the size of CA, decrease complications and improve pregnancy outcomes.