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Cutting performance of surgical electrodes by constructing bionic microstriped structures

《机械工程前沿（英文）》 2023年第18卷第1期 doi: 10.1007/s11465-022-0728-9

摘要： Surgical electrodes rely on thermal effect of high-frequency current and are a widely used medical tool for cutting and coagulating biological tissue. However, tissue adhesion on the electrode surface and thermal injury to adjacent tissue are serious problems in surgery that can affect cutting performance. A bionic microstriped structure mimicking a banana leaf was constructed on the electrode via nanosecond laser surface texturing, followed by silanization treatment, to enhance lyophobicity. The effect of initial, simple grid-textured, and bionic electrodes with different wettabilities on tissue adhesion and thermal injury were investigated using horizontal and vertical cutting modes. Results showed that the bionic electrode with high lyophobicity can effectively reduce tissue adhesion mass and thermal injury depth/area compared with the initial electrode. The formation mechanism of adhered tissue was discussed in terms of morphological features, and the potential mechanism for antiadhesion and heat dissipation of the bionic electrode was revealed. Furthermore, we evaluated the influence of groove depth on tissue adhesion and thermal injury and then verified the antiadhesion stability of the bionic electrode. This study demonstrates a promising approach for improving the cutting performance of surgical electrodes.

关键词： surgical electrodes tissue adhesion thermal injury bionic structures cutting performance medical tools

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Bile duct injury repair — earlier is not better

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《医学前沿（英文）》 2015年第9卷第4期页码 508-511 doi: 10.1007/s11684-015-0418-7

摘要：

Bile duct injury is a common complication of cholecystectomy. The timing of bile duct injury repair remains controversial. A recent review conducted in France reported 39% complications and 64% failure after immediate repair in 194 patients compared with 14% complications and 8% failure after late repair in 133 patients. A national review of 139 consecutive early repairs conducted at five hepatopancreaticobiliary centers in Denmark reported 4% mortality, 36% morbidity, and 42 restrictures (30%) at a median follow-up of 102 months, and only 64 patients (46%) demonstrated uneventful short-term and long-term outcomes. Most patients with bile duct injury present with bile leak and sepsis; thus, early repair is not recommended. Percutaneous drainage of bile and endoscopic stenting are the mainstays of treatment of bile leak because they convert acute bile duct injury into a controlled external biliary fistula. The ensuing benign biliary stricture should be repaired by a biliary surgeon after a delay of 4–6 weeks once the external biliary fistula has closed.

关键词： bile duct injury cholecystectomy laparoscopic cholecystectomy

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Loss of monocarboxylate transporter 1 aggravates white matter injury after experimental subarachnoid

《医学前沿（英文）》 2021年第15卷第6期页码 887-902 doi: 10.1007/s11684-021-0879-9

摘要： Monocarboxylic acid transporter 1 (MCT1) maintains axonal function by transferring lactic acid from oligodendrocytes to axons. Subarachnoid hemorrhage (SAH) induces white matter injury, but the involvement of MCT1 is unclear. In this study, the SAH model of adult male Sprague-Dawley rats was used to explore the role of MCT1 in white matter injury after SAH. At 48 h after SAH, oligodendrocyte MCT1 was significantly reduced, and the exogenous overexpression of MCT1 significantly improved white matter integrity and long-term cognitive function. Motor training after SAH significantly increased the number of ITPR2⁺SOX10⁺ oligodendrocytes and upregulated the level of MCT1, which was positively correlated with the behavioral ability of rats. In addition, miR-29b and miR-124 levels were significantly increased in SAH rats compared with non-SAH rats. Further intervention experiments showed that miR-29b and miR-124 could negatively regulate the level of MCT1. This study confirmed that the loss of MCT1 may be one of the mechanisms of white matter damage after SAH and may be caused by the negative regulation of miR-29b and miR-124. MCT1 may be involved in the neurological improvement of rehabilitation training after SAH.

关键词： microRNAs monocarboxylate transporter 1 motor training subarachnoid hemorrhage white matter injury

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Risk factors of prognosis after acute kidney injury in hospitalized patients

null

《医学前沿（英文）》 2017年第11卷第3期页码 393-402 doi: 10.1007/s11684-017-0532-9

摘要：

The risk factors, especially laboratory indicators, of prognosis after acute kidney injury (AKI) remain unclear. We conducted a retrospective survey of Chinese People’s Liberation Army General Hospital from January 1, 2012 to December 31, 2012 according to the AKI diagnosis standard issued by Kidney Disease Improving Global Outcomes. The epidemiological features and factors influencing hospital mortality and renal function recovery were evaluated through logistic regression analysis. Among 77 662 cases of hospitalized patients, 1387 suffered from AKI. The incidence rate and mortality of AKI were 1.79% and 14.56%, respectively. Multivariate logistic regression analysis revealed that high AKI stage, age greater than 80 years, neoplastic disease, low cardiac output, increased white blood cell count, and decreased platelet count and serum albumin levels were the risk factors affecting the mortality of AKI patients. Conversely, body mass index between 28 and 34.9 was a protective factor. Increased AKI stage, tumor disease, post-cardiopulmonary resuscitation, and RRT were the risk factors of renal function recovery upon discharge. In addition to traditional risk factors, white blood cell count, platelet count, albumin, and BMI were the predictors of the mortality of AKI patients. No laboratory indicators were found to be the risk factors of renal function recovery in AKI patients.

关键词： acute kidney injury risk factors prognosis

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Leonurine protects ischemia-induced brain injury via modulating SOD, MDA and GABA levels

Shilei ZHENG, Jingru ZHU, Jiao LI, Shuang ZHANG, Yunfei MA

《农业科学与工程前沿（英文）》 2019年第6卷第2期页码 197-205 doi: 10.15302/J-FASE-2018245

摘要：

The present study was designed to investigate the protective effects of leonurine, a compound purified from that is active on ischemic rat behavior and cortical neurons, and explore the underlying mechanism. The general rat activity, cortical neuron morphology, superoxide dismutase (SOD), malondialdehyde (MDA), -aminobutyric acid (GABA) and glutamate decarboxylase 67 (GAD67) levels were measured. We found leonurine significantly improve the general activity of rats in an open-field test, which was associated with attenuated neuronal damage induced by ischemia. Moreover, serum SOD activity was significantly greater, MDA level lower in the leonurine group as compared with ischemia group. In addition, GABA content in the cerebral cortex was significantly greater in high-dose leonurine group. Correspondingly, GAD67 protein level coincided with the GABA level. Taken together, our results demonstrated that leonurine attenuated brain injury during ischemia via antioxidative and anti-excitotoxicity effects by targeting GABA and leonurine might become a useful adjuvant neuroprotective agent.

关键词： cerebral ischemia GABA neuroprotection leonurine SOD

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Progress and perspectives of neural tissue engineering

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《医学前沿（英文）》 2015年第9卷第4期页码 401-411 doi: 10.1007/s11684-015-0415-x

摘要：

Traumatic injuries to the nervous system lead to a common clinical problem with a quite high incidence and affect the patient’s quality of life. Based on a major challenge not yet addressed by current therapeutic interventions for these diseases, a novel promising field of neural tissue engineering has emerged, grown, and attracted increasing interest. This review provides a brief summary of the recent progress in the field, especially in combination with the research experience of the author’s group. Several important aspects related to tissue engineered nerves, including the theory on their construction, translation into the clinic, improvements in fabrication technologies, and the formation of a regenerative environment, are delineated and discussed. Furthermore, potential research directions for the future development of neural tissue engineering are suggested.

关键词： nerve injury tissue engineering nerve grafts

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Protective effect of N-acetylcysteine against lipopolysaccharide injury in hepatocytes of neonatal mice

WANG Lin, LIU Yalan, XU Jianbo, TIAN Yuan, WU Heshui

《医学前沿（英文）》 2008年第2卷第2期页码 182-185 doi: 10.1007/s11684-008-0034-x

摘要： The present study provides supportive evidence for the effective prevention and treatment of lipopolysaccharide (LPS)-induced hepatocyte injury in neonatal mice by N-acetylcysteine (NAC). Hepatocytes of neonatal mice were obtained through collagenase digestion of the liver. The hepatocytes were treated either with LPS (10 ?g/mL) alone or with NAC (5 mmol/L) for 1 h before the addition of LPS (10 ?g/mL). After LPS treatment, 12 wells of the cultured hepatocytes and supernatants were harvested at 0, 6, and 12 h, respectively. Levels of alanine aminotransferase (ALT) and nitric oxide (NO) in the supernatant were biochemically quantified and reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect the expression of inducible nitric oxide synthase (iNOS) mRNA after different treatments. At 0 h following the treatment of primary cultured hepatocytes with LPS, the levels of ALT, NO and iNOS mRNA in the supernatant were (21.1 ± 4.78) u/L, (1.6 ± 0.31) ?mol/L and 0.17 ± 0.023, respectively; at 6 h, (59.8 ± 8.59) u/L, (6.6 ± 0.81) ?mol/L, and 0.71 ± 0.091; and at 12 h, (89.6 ± 15.30) u/L, (7.8 ± 1.01) ?mol/L, and 0.71 ± 0.097. The levels of ALT, NO and iNOS mRNA at 6 and 12 h increased significantly, compared to those at 0 h ( < 0.01). In contrast to LPS treatment alone, pretreatment with NAC before LPS addition significantly reduced the levels of ALT, NO and iNOS mRNA in the supernatant at 6 h to (40.8 ± 7.30) u/L, (3.2 ± 0.71) ?mol/L, and 0.41 ± 0.060; and at 12 h to (55.4 ± 5.48) u/L, (4.0 ± 0.71) ?mol/L, and 0.40 ± 0.067, respectively ( < 0.01). However, the levels of ALT, NO and iNOS mRNA at 0 h did not change significantly with both treatment approaches. NAC has protective effects in hepatocytes of neonatal mice against LPS-induced injury as shown by the reduced levels of ALT, NO and iNOS mRNA when primary hepatocytes were treated with NAC prior to LPS stimulation. We postulate that NAC exhibits its protective function by inhibiting LPS-induced transcription of iNOS, resulting in decreased levels of NO.

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Effect of oxytocin on gastric ischemia-reperfusion injury in rats

ZHANG Wenwen, ZHANG Jianfu, ZHANG Yongmei, XU Ming

《医学前沿（英文）》 2007年第1卷第4期页码 433-437 doi: 10.1007/s11684-007-0085-4

摘要： The effect of peripherally administered oxytocin (OT) on gastric ischemia-reperfusion injury (GI-RI) and its possible mechanism were investigated. The Sprague-Dawley (SD) rats were randomly divided into different treatment groups ( = 6). The animal GI-RI model was established by clamping the celiac artery for 30 min to induce ischemia and then released to allow reperfusion for 1 h, and the degree of GI-RI was assessed by scoring the gastric mucosal damage index (GMDI), the gastric fluid output, gastric fluid output, gastric acidity were measured and the surgical preparations of vagotomy and sympathectomy were used to investigate the possible mechanism of OT on GI-RI. The results were as follows. Compared with the control group (NS plus GI-R only, GMDI 121.33±10.40, = 6), the intra peritoneal (ip) administration of oxytocin (20, 100 μg/0.5 mL) obviously attenuated GI-RI (<0.05), GMDI were 82.33±14.26, 53.5±5.58 respectively ( = 6); the gastric fluid output and the gastric acidity (evaluated by pH) of the control group were (430.17±87.36) μL, 1.55±0.25 ( = 6), and those of the OT group were (102.45±48.00) μL, 2.65±0.40 ( = 6) res pectively; differences had statistical significance (<0.01). The effect of oxytocin was reversed by atosiban, a selective oxytocin receptor antagonist. The GMDI of the group given atosiban 10 min before OT was 138.17±24.06 ( = 6), which had no significant difference with the control group. Oxytocin further attenuated GI-RI after vagotomy and sympathectomy (GMDI 6.83±8.89, 29.67±5.54, = 6), compared with the GI-R group and the oxytocin group (<0.01). These results indicated that the oxytocin could significantly protect gastric mucosal against injury induced by ischemia-reperfusion, and the oxytocin receptor was involved. This effect of oxytocin may be mediated through the vagus and sympathetic nerve, and then lead to the reduction of gastric juice output and the depression of gastric acidity.

关键词： control significant difference surgical statistical significance Sprague-Dawley

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Rdh13 deficiency weakens carbon tetrachloride-induced liver injury by regulating Spot14 and Cyp2e1 expression

Xiaofang Cui, Benting Ma, Yan Wang, Yan Chen, Chunling Shen, Ying Kuang, Jian Fei, Lungen Lu, Zhugang Wang

《医学前沿（英文）》 2019年第13卷第1期页码 104-111 doi: 10.1007/s11684-017-0568-x

摘要： Mitochondrion-localized retinol dehydrogenase 13 (Rdh13) is a short-chain dehydrogenase/reductase involved in vitamin A metabolism in both humans and mice. We previously generated knockout mice and showed that Rdh13 deficiency causes severe acute retinal light damage. In this study, considering that Rdh13 is highly expressed in mouse liver, we further evaluated the potential effect of Rdh13 on liver injury induced by carbon tetrachloride (CCl ). Although Rdh13 deficiency showed no significant effect on liver histology and physiological functions under regular culture, the mice displayed an attenuated response to CCl -induced liver injury. Their livers also exhibited less histological changes and contained lower levels of liver-related metabolism enzymes compared with the livers of wild-type (WT) mice. Furthermore, the mice had Rdh13 deficiency and thus their liver cells were protected from apoptosis, and the quantity of their proliferative cells became lower than that in WT after CCl exposure. The ablation of gene decreased the expression levels of thyroid hormone-inducible nuclear protein 14 (Spot14) and cytochrome P450 (Cyp2e1) in the liver, especially after CCl treatment for 48 h. These data suggested that the alleviated liver damage induced by CCl in mice was caused by Cyp2e1 enzymes, which promoted reductive CCl metabolism by altering the status of thyroxine metabolism. This result further implicated Rdh13 as a potential drug target in preventing chemically induced liver injury.

关键词： retinol dehydrogenase 13 carbon tetrachloride acute liver injury Cyp2e1 Spot14

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Effect of intestinal ischemia/reperfusion injury on leptin and orexin-A levels

LIN Ji, YAN Guangtao, HAO Xiuhua, ZHANG Kai, GAO Xiaoning, LIAO Jie

《医学前沿（英文）》 2007年第1卷第1期页码 87-92 doi: 10.1007/s11684-007-0017-3

摘要： The aim of this paper is to explore the effect of intestinal ischemia/reperfusion (I/R) injury on leptin and orexin-A levels in peripheral blood and central secretory tissues, and to examine the roles of leptin and orexin-A in acute inflammatory responses. An intestinal I/R injury model of rats was made; the rats were grouped according to the time of after 60 min ischemia. Radioimmunoassay was employed to detect the levels of leptin in serum and adipose tissue and orexin-A levels in plasma and hypothalamus. Reverse transcriptase-polymerase chain reaction was used to detect mRNA expressions of adipose leptin and hypothalamus orexin-A. Compared with the levels before the injury, serum leptin in 60 min ischemia/30 min reperfusion (I60´R30´) group decreased and that of I60´R360´ group increased. Compared with sham-operation group (sham group) after injury, serum leptin level of I60´R360´ group increased, adipose leptin levels of I60´R30´ and I60´R90´ decreased, and adipose leptin in I60´R360´ group increased. After the injury, adipose leptin mRNA expressions of I60´R30´, I60´R240´ and I60´R360´ increased, whereas that of I60´R150´ group decreased as compared with the sham group. There was no significant difference in the protein levels of orexin-A, either between plasma and hypothalamus or between pre- and post-I/R injury. Compared with sham group, hypothalamus orexin-A mRNA expressions of I60´R30´ and I60´R90´ decreased gradually after the injury, with that of I60´R150´ group reaching the lowest, and those of I60´R240´ and I60´R360´ recovering gradually, although they were still significantly lower than that of sham group. Leptin and orexin-A respond to intestinal I/R injury in a time-dependent manner, with leptin responding more quickly than orexin-A does, and both of them may contribute to the metabolic disorders in acute inflammation.

关键词： significant difference intestinal I/R transcriptase-polymerase metabolic central secretory

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Glucagon-like peptide-2 exhibits protective effect on hepatic ischemia-reperfusion injury in rats

null

《医学前沿（英文）》 2015年第9卷第3期页码 368-373 doi: 10.1007/s11684-015-0403-1

摘要：

Glucagon-like peptide-2 (GLP-2) has potent anti-inflammatory effects and protects against experimental ischemia/reperfusion (I/R) injury in pulmonary, intestinal, and myocardial tissue. However, its protective abilities against I/R injury in the liver are unknown. We investigated the potential role of GLP-2 pretreatment on hepatic I/R injury in rats. A total of 24 rats were randomly divided into three groups (n = 8). The first group was the control group; the second group was the vehicle-treated hepatic ischemia/reperfusion (HIR, vehicle saline-treated) group; and the third group was the GLP-2 pretreated I/R (GLP2-IR) group. Each rat in the third group was intraperitoneally administered 5 μg GLP-2 for 5 d before the procedure. A portal triad was created to induce ischemia with a vascular atraumatic clamp. After 40 min, the clamp was released to initiate hepatic reperfusion for 6 h. Blood samples and tissue specimens from the liver were obtained. Alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels significantly increased in the saline-treated HIR group (P<0.001), whereas GLP-2 pretreatment significantly decreased their levels (P<0.01). Our data suggested that GLP-2 pretreatment may have a protective effect on liver I/R injury. However, dose-response studies are necessary to determine the most effective dose.

关键词： ischemia/reperfusion liver glucagon-like peptide-2 alanine aminotransferase

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组织再生：梦想、希望和挑战

付小兵

《中国工程科学》 2009年第11卷第10期页码 122-128

摘要：

组织再生是21世纪生物学和医学领域研究的重点和热点。在回顾再生医学研究历史的基础上，概要介绍了组织再生所涉及的关键科学问题、重大需求以及部分已经取得的重要进展，并对将来的发展进行了展望。

关键词：损伤组织修复再生

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Evidence chain-based causality identification in herb-induced liver injury: exemplification of a well-known

null

《医学前沿（英文）》 2015年第9卷第4期页码 457-467 doi: 10.1007/s11684-015-0417-8

摘要：

Herbal medicines have recently been recognized as the second most common cause of drug-induced liver injury (DILI) in the United States. However, reliable methods to identify the DILI causality of some herbs, such as Heshouwu (dried root of Polygonum multiflorum), remain lacking. In this study, a total of 12 307 inpatients with liver dysfunction and 147 literature-reported cases of Heshouwu DILI were screened. A general algorithm indicated that only 22.5% (9/40) and 30.6% (45/147) of all hospitalization and literature case reports, respectively, demonstrate the high probability of DILI causality of Heshouwu. By contrast, 95% (19/20) of all cases prospectively investigated by pharmacognosy, phytochemistry, and metabolomic tests exhibited highly probable causality, including a patient who was previously incorrectly attributed and a case that was excluded from Heshouwu causality by pharmacognostic evidence. Toxin (heavy metals, pesticides, and mycotoxins) contamination was also excluded from Heshouwu DILI causality. The objectivity of these screening methods for Heshouwu DILI diagnosis addresses safety concerns regarding stilbene-containing herbal medicines and dietary supplements.

关键词： drug-induced liver injury pharmacognosy metabolomics stilbene Polygonum multiflorum Chinese herbal medicine

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Influence evaluation of loading conditions during pressurized thermal shock transients based on thermal-hydraulics

Jinya KATSUYAMA, Shumpei UNO, Tadashi WATANABE, Yinsheng LI

《机械工程前沿（英文）》 2018年第13卷第4期页码 563-570 doi: 10.1007/s11465-018-0487-9

摘要：

The thermal hydraulic (TH) behavior of coo-lant water is a key factor in the structural integrity assessments on reactor pressure vessels (RPVs) of pressurized water reactors (PWRs) under pressurized thermal shock (PTS) events, because the TH behavior may affect the loading conditions in the assessment. From the viewpoint of TH behavior, configuration of plant equipment and their dimensions, and operator action time considerably influence various parameters, such as the temperature and flow rate of coolant water and inner pressure. In this study, to investigate the influence of the operator action time on TH behavior during a PTS event, we developed an analysis model for a typical Japanese PWR plant, including the RPV and the main components of both primary and secondary systems, and performed TH analyses by using a system analysis code called RELAP5. We applied two different operator action times based on the Japanese and the United States (US) rules: Operators may act after 10 min (Japanese rules) and 30 min (the US rules) after the occurrence of PTS events. Based on the results of TH analysis with different operator action times, we also performed structural analyses for evaluating thermal-stress distributions in the RPV during PTS events as loading conditions in the structural integrity assessment. From the analysis results, it was clarified that differences in operator action times significantly affect TH behavior and loading conditions, as the Japanese rule may lead to lower stresses than that under the US rule because an earlier operator action caused lower pressure in the RPV.

关键词： structural integrity reactor pressure vessel pressurized thermal shock thermal hydraulic analysis pressurized water reactor weld residual stress

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Assessment indices for uniform and non-uniform thermal environments

ZHANG Yufeng, SUN Shufeng, ZHAO Rongyi

《能源前沿（英文）》 2008年第2卷第2期页码 129-133 doi: 10.1007/s11708-008-0029-y

摘要： Different assessment indices for thermal environments were compared and selected for proper assessment of indoor thermal environments. 30 subjects reported their overall thermal sensation, thermal comfort, and thermal acceptability in uniform and non-uniform conditions. The results show that these three assessment indices provide equivalent evaluations in uniform environments. However, overall thermal sensation differs from the other two indices and cannot be used as a proper index for the evaluation of non-uniform environments. The relationship between the percentage and the mean vote for each index is established.

关键词： thermal sensation proper assessment relationship equivalent thermal acceptability