Protective effect of Epothilone D against traumatic optic nerve injury in rats / 南方医科大学学报

OBJECTIVE@#To investigate the therapeutic effect of Epothilone D on traumatic optic neuropathy (TON) in rats.@*METHODS@#Forty-two SD rats were randomized to receive intraperitoneal injection of 1.0 mg/kg Epothilone D or DMSO (control) every 3 days until day 28, and rat models of TON were established on the second day after the first administration. On days 3, 7, and 28, examination of flash visual evoked potentials (FVEP), immunofluorescence staining and Western blotting were performed to examine the visual pathway features, number of retinal ganglion cells (RGCs), GAP43 expression level in damaged axons, and changes of Tau and pTau-396/404 in the retina and optic nerve.@*RESULTS@#In Epothilone D treatment group, RGC loss rate was significantly decreased by 19.12% (P=0.032) on day 3 and by 22.67% (P=0.042) on day 28 as compared with the rats in the control group, but FVEP examination failed to show physiological improvement in the visual pathway on day 28 in terms of the relative latency of N2 wave (P=0.236) and relative amplitude attenuation of P2-N2 wave (P=0.441). The total Tau content in the retina of the treatment group was significantly increased compared with that in the control group on day 3 (P < 0.001), showing a consistent change with ptau-396/404 level. In the optic nerve axons, the total Tau level in the treatment group was significantly lower than that in the control group on day 7 (P=0.002), but the changes of the total Tau and pTau-396/404 level did not show an obvious correlation. Epothilone D induced persistent expression of GAP43 in the damaged axons, detectable even on day 28 of the experiment.@*CONCLUSION@#Epothilone D treatment can protect against TON in rats by promoting the survival of injured RGCs, enhancing Tau content in the surviving RGCs, reducing Tau accumulation in injured axons, and stimulating sustained regeneration of axons.

Research on flash visual evoked potential and dynamic changes of Tau and its phosphorylation in rat model of traumatic optic neuropathy / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To detect the visual dysfunction, and investigate the changes of Tau and its phosphorylated Ser396/Ser404 forms in retinas and optic nerves in traumatic optic neuropathy(TON)model rats by using FVEP technique.<p>METHODS: Totally 30 SD rats were conducted FVEP electrode implantation. One week later, all rates were implemented TON operation with the optic nerve of left eye crushed and the optic nerve of right eye exposed(sham-operated). FVEP detections were performed respectively in these TON model rats at 1, 3, 7, 14, and 28d post crush, with 5 rats tested at each time point. After FVEP tests were taken, rats were sacrificed and then retinas and optic nerves of left eyes were separated for detecting the expression levels of Tau and pTau-Ser396/404 by Western Blot.<p>RESULTS: Typical FVEP waves were observed in the sham-operated eyes. Compared to the sham group, the N2 waves were significantly delayed and the amplitude of N2-P2 were greatly reduced at each time point in the operation eyes. However, the differences of N2 wave and the amplitude reduction of N2-P2 were not significant at each time point after crush. The contents of total Tau protein in retinas of TON rats sharply decreased at 1d post crush, briefly recovered at 7d post crush, and remained a slightly lower level than normal condition till 28d. The changes of pTau-Ser396/404 were consistent with the changes of total Tau in retains and the Ser396 was the main phosphorylation site. However, the total Tau contents in optic nerves of TON rats increased gradually, and peaked at the 14d post crush and remained till 28d. The changes of pTau-Ser396/404 were similar to the changes of total Tau in optic nerves, which peaked at 7d post crush. However, Ser404 was the main phosphorylation site of Tau in optic nerves.<p>CONCLUSION: The related indexes of N2 and P2 waves in FVEP can be used to detect the visual dysfunction in TON rats. After TON, the content changes of total Tau in retinas and optic nerves were much different while the changes of pTau-Ser396/404 followed the alterations of total Tau in the two locations. However, the main phosphorylation site of Tau was differnet according to the locations.

Treatment of intertrochanteric fracture of femur with closed reduction of proximal femoral anti rotation intramedullary nail in supine position / 中国骨伤

OBJECTIVE@#To investigate the effect and feasibility of closed reduction and internal fixation with PFNA in the treatment of intertrochanteric fracture of femur in the supine position without traction bed.@*METHODS@#From June 2014 to March 2018, 45 patients with intertrochanteric fracture of femur who were treated and followed up were analyzed retrospectively. There were 21 males and 24 females, with an average age of 67.4 years (43 to 92 years);18 cases on the left side and 27 on the right side. According to Evans Jensen classification, there were 7 patients of type Ⅱ, 17 patients of type Ⅲ, 16 patients of type Ⅳ and 5 patients of type Ⅴ. The time from injury to operationwas 2 to 6 days. The operation time, blood loss and fracture healing, closing time, postoperative complications and Harris score of hip joint were recorded.@*RESULTS@#The operation time of 45 patients was 35 to 80 min, with an average of 52.6 min;the intraoperative bleeding volume was 40 to 110 ml, with an average of 68.7 ml;the hospitalization time was 6 to 11 days, with an average of 8.4 days;the follow up time was 12 to 18 months, with an average of 14.7 months;the internal fixation of 2 patients failed, and 43 patients achieved bony healing;the deep vein thrombosis of the lower extremity in the perioperative period was 1 case, and the inferior vena cava filter was inserted;the internal fixation of 2 patients was cut out, and the hip was renovated. The incidence of complications was 8.9%(4 / 45). At the final follow up, Harris score of hip joint was 56 to 95 (81.30±8.40), including excellent 15 cases, good 26 cases, fair 2 cases and poor 2 cases.@*CONCLUSION@#It is safe and feasible to treat intertrochanteric fracture of femur with closed reduction and anti rotation intramedullary nailing under the bed without traction in a supine position. It has the advantages of small trauma and low complications, and the clinical effect is satisfactory. It is worth popularizing and using in basic hospitals.

Vitamin D Improves Intestinal Barrier Function in Cirrhosis Rats by Upregulating Heme Oxygenase-1 Expression

Intestinal barrier dysfunction always accompanies cirrhosis in patients with advanced liver disease and is an important contributor facilitating bacterial translocation (BT), which has been involved in the pathogenesis of cirrhosis and its complications. Several studies have demonstrated the protective effect of Vitamin D on intestinal barrier function. However, severe cholestasis leads to vitamin D depletion. This study was designed to test whether vitamin D therapy improves intestinal dysfunction in cirrhosis. Rats were subcutaneously injected with 50% sterile CCl₄ (a mixture of pure CCl₄ and olive oil, 0.3 mL/100 g) twice a week for 6 weeks. Next, 1,25(OH)₂D₃(0.5 µg/100 g) and the vehicle were administered simultaneously with CCl₄ to compare the extent of intestinal histologic damage, tight junction protein expression, intestinal barrier function, BT, intestinal proliferation, apoptosis, and enterocyte turnover. Intestinal heme oxygenase-1 (HO-1) expression and oxidative stress were also assessed. We found that vitamin D could maintain intestinal epithelial proliferation and turnover, inhibit intestinal epithelial apoptosis, alleviate structural damage, and prevent BT and intestinal barrier dysfunction. These were achieved partly through restoration of HO-1 and inhibition of oxidative stress. Taken together, our results suggest that vitamin D ameliorated intestinal epithelial turnover and improved the integrity and function of intestinal barrier in CCl₄-induced liver cirrhotic rats. HO-1 signaling activation was involved in these above beneficial effects.

Research Progress of Traditional Chinese Medicine in Treating Diabetes Mellitus Based on PI3K/Akt Pathway / 中国实验方剂学杂志

Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia, with a high incidence and many complications. It has become an increasingly serious public health problem in the world, and has seriously affected the quality of life. Phosphatidylinositol-3-kinases (PI3K)/protein kinase B (Akt) signaling pathway is the main pathway of insulin signal transmission and the main signal channel for regulating blood glucose. The abnormal signal molecule of PI3K/Akt may cause abnormal signal transduction pathway, so as to impact the proliferation, apoptosis, metastasis and invasion of the corresponding tissues and organs, and lead to the occurrence of disease. Study of PI3K/Akt signal channel has a positive significance for investigating whether traditional Chinese medicine(TCM) has a definite and stable hypoglycemic effect. Currently, there are many TCM and Western medicines to treat diabetes, however, most drugs, especially Western medicines, have a relatively poor effect in controlling complications. To understand the progress of TCM in treatment of diabetes, in expectation of better studying the comprehensive therapeutic effect and mechanism of TCM on diabetes, and further developing the multi-target, multi-way and multi-channel advantages and features of TCM in the treatment of diabetes, this paper focuses on a systematic analysis on the progress of in vivo and in vitro studies on DM based on PI3K/Akt signaling channel in recent years, including the effect of the signaling channel on insulin secretion, the three main target organs of insulin (liver, skeletal muscle and fat), and its effect on the four main complications of diabetes (brain, kidney, heart, testis), and also provides certain ideas and guidance for the study of hypoglycemic mechanism of TCM monomer, TCM and compound medicine.

Expression of CD63 in Lung Tissue of Guinea Pigs Dying of Anaphylactic Shock / 法医学杂志

Objective To study the protein expression of cluster of differentiation 63 （CD63） in lung tissues of guinea pigs that died of anaphylactic shock and discuss the diagnostic value of CD63 for death from anaphylactic shock. Methods Twenty guinea pigs were randomly divided into control group, anaphylactic shock immediate death group, cold storage group （4 ℃ for 48 h） and frozen group （-20 ℃ for 7 d）. The animal model of guinea pigs that died of anaphylactic shock was established with human mixed serum injection. The expression changes of CD63 protein and CD63 mRNA in lung tissues were detected by hematoxylin-eosin （HE） staining, immunohistochemical staining, Western blotting, enzyme-linked immunosorbent assay （ELISA） and real-time RT-PCR. Results HE staining results showed congestion, and edema of lung tissues, and eosinophil infiltration in the anaphylactic shock groups. Western blotting analysis results showed that the expression of CD63 protein in the lung tissues of guinea pigs that died of anaphylactic shock was significantly higher than that in the control group （P<0.05）. Comparison between the anaphylactic shock groups was made, and the differences had no statistical significance. The results of immunohistochemical staining and real-time RT-PCR were consistent with that of Western blotting. ELISA results showed that CD63 protein expression in the immediate death group was higher than that in the control group （P<0.05）. Conclusion The expression of CD63 protein and CD63 mRNA in the lung tissues of guinea pigs that died of anaphylactic shock is significantly enhanced. Animal carcasses which were put in cold storage for 48 h and frozen for 7 d do not affect the examination of the above indicators. CD63 protein is expected to become an auxiliary diagnostic indicator of death from anaphylactic shock.

Relationship between Expression Changes of CB2R and Wound Age of Brain Contusion in Mice / 法医学杂志

Objective To investigate the expression of cannabinoid type 2 receptor （CB2R） at different time points after brain contusion and its relationship with wound age of mice. Methods A mouse brain contusion model was established with PCI3000 Precision Cortical Impactor. Expression changes of CB2R around the injured area were detected with immunohistochemical staining, immunofluorescent staining and Western blotting at different time points. Results Immunohistochemical staining results showed that only a few cells in the cerebral cortex of the sham operated group had CB2R positive expression. The ratio of CB2R positive cells gradually increased after injury and reached the peak twice at 12 h and 7 d post-injury, followed by a decrease to the normal level 28 d post-injury. The results of Western blotting were consistent with the immunohistochemical staining results. Immunofluorescent staining demonstrated that the changes of the ratio of CB2R positive cells in neurons, CB2R positive cells in monocytes and CB2R positive cells in astrocytes to the total cell number showed a single peak pattern, which peaked at 12 h, 1 d and 7 d post-injury, respectively. Conclusion The expression of CB2R after brain contusion in neurons, monocytes and astrocytes in mice suggests that it is likely to be involved in the regulation of the biological functions of those cells. The changes in CB2R are time-dependent, which suggests its potential applicability as a biological indicator for wound age estimation of brain contusion in forensic practice.

A new dimeric xanthanolide from fruits of Xanthium chinense / 中国中药杂志

Through the methods of polyamide resin， Sephadex LH-20， ODS column chromatography and preparative HPLC etc.， 7 compounds were isolated from the 70% ethanol extract of the fruits of Xanthium chinense. Based on ESI-MS and NMR data， the structures of these compounds were identified as pungiolide O(1)， grasshopper ketone(2)， icariside F₂(3)， 7-[(β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyl)oxymethy]-8，8-dimethyl-4，8-dihydrobenzo[1，4]thiazine-3，5-dione(4)，(6R，9S)-3-oxo-α-ionol β-D-glucopyranoside(5)， cryptochlorogenic acid methyl ester(6)， and chlorogenic acid methyl ester(7). Among them， compound 1 is a new compound.

Application of RapidHITTM 200 System in Forensic Medicine / 法医学杂志

Objective To validate the analysis capability of RapidHITTM 200 system for four kinds of routine forensic samples and the recyclable capability of template, template DNA and PCR products in the process of twice duplicate detection. Methods The buccal swabs underwent the test twice by RapidHITTM 200 system, and the template DNA and PCR products that arose in the system were also tested for two times. After four kinds of routine forensic samples were detected by RapidHITTM 200 system, the follow-up tests of the template, template DNA and PCR products that arose in the system were performed. Re-sults The STR loci could be detected in the buccal swabs by the system for the first time. However, part of the STR loci lost during the second test. And the peak value obtained in the second test was significantly reduced than the one in the first time. The average STR loci detection rates of the template DNA and PCR products were both less than 50％ in the second test, which were significantly reduced than that in the first test. In addition, the analysis capability of the system for the tissues and buccal swabs was better than that for the blood and cigarette butts. Compared with the first test, the STR loci detection rate of the tested items, template DNA and PCR products decreased with the numbers of tests. Conclusion RapidHITTM 200 system is more effective in retesting buccal swabs than other samples, whereas the items, DNA template, PCR products obtained in the first and second time cannot be directly used for the further application and study of forensic medicine.

Study on quality control method of toad venom based on characteristic chromatogram and QAMS / 中国中药杂志

Toad venom (Chansu) is prepared from the dried secretion of parotid gland and skin gland from Bufo bufo gargarizans or B. melanostictus. Up to now, much attention shall be paid to the poor quality of commercial toad venom because of the adulteration. So, it is urgent to establish a scientific and perfect quality control method to improve the quality of toad venom and guarantee its safety and effectiveness in clinical application. The different batches of toad venom samples were assayed by high performance liquid chromatography (HPLC) and the quantitative analysis of multi-components by single marker (QAMS) was used to detect the contents of five bufagenins. As a result, the reference characteristic chromatogram was established, displaying serotonin, gamabufotalin, arenobufagin, hellebrigenin, telocinobufagin, bufotalin, cinobufotalin, bufalin, cinobufagin and resibufogenin as characteristic peaks. Taking cinobufagin as an internal reference substance, QAMS was verified for the determination of five bufagenins (gamabufotalin, bufotalin, bufalin, cinobufagin, resibufogenin) in toad venom samples. The durability and applicability of the relative correction factor (RCF) were also studied systematically. RCFs of cinobufagin to gamabufotalin, bufotalin, bufalin and resibufogenin were determined as 1.05, 0.895, 1.09 and 0.913, respectively. The characteristic chromatogram and QAMS established in this study could effectively control the quality of toad venom and provide scientific evidence for the improvement of the quality standard of the toad venom to be described in Chinese Pharmacopoeia (2020 edition).

Structural identification of related substances in Breviscapine by UPLC-QTOF-MS / 中国中药杂志

To systematically identify the related substances in the original materials of breviscapine injection, 18 batches of samples collected from different pharmaceutical companies, its ethanol extract and breviscapine mother liquor concentrate were analyzed by high performance liquid chromatography (HPLC), and their structures were identified by ultra performance liquid chromatography and quadruple/time-of-flight mass spectrometry (UPLC-QTOF-MS). Under the selected chromatographic conditions, scutellarin and related substances have good resolution and 13 related substances were observed. Based on the molecular weight and fragmentation patterns obtained by UPLC-QTOF-MS as well as reference substances, their structures were elucidated as 6-hydroxyapigenin-6--glucosyl-7--glucuronide (1), 5,7,8,3',4',5'-hexahydroxyflavone-7--glucuronide (2), 5,6,7,3',4'-pentahydroxyflavone-7--glucuronide（3）and its isomer (4), patuletin-3--glucuronide (5), methoxylscutellarin (6), apigenin 7--glucuronide (7), isorhamnetin 7--glucuronide (8), diosmetin 7--glucuronide (9), scutellarein (10), scutellarin methyl ester (11), scutellarin ethyl ester (12), and apigenin (13). This study has clarified related substances in the original materials of breviscapine injection, providing references for the improvement of quality control for breviscapine drug material and its preparations.

Advance on quality control of toad venom and its key influence factors / 中国中药杂志

Toad venom (Chansu) is prepared from the dried secretion of Bufo bufo gargarizans or B. melanostictus. It is not only one of the famous and expensive traditional Chinese medicines(TCMs) from animal origin, but also one of 28 kinds of toxic TCMs to be required for special management issued by the State Council of the People's Republic of China. Chansu contains the rich bufadienolides and indole alkaloids, and displays various bioactivity including cardiotonic, anti-tumor, analgesia, and local anesthesia. Based on the published references in the recent years, the advance on the identification of adulterants and quality evaluation as well as the influence factors on the quality of toad venom was summarized to improve the quality standards and promote the level of quality control of toad venom and its preparations.

The Overview of Galli gigerii endothelium Corneum, an Edible Traditional Chinese Medicine / 中国药学杂志

Galli gigerii endothelium corneum is collected from the dried inner wall of the stomach of Gallus gallus domesticus Brisson and it is used for a long history as an edible traditional Chinese medicine. Galli gigerii endothelium corneum contains rich nutrient components such as proteins, polysaccharides, animo acids, and trace elements, and displayed various bioactivities including anti-oxidative effect, improving the level of blood glucose and lipid, as well as hemorheological parameters and gastrointestinal function. Based on the published literatures in the recent years, the advance in the research on the traditional use, chemical constituents, pharmacological activities of Galli gigerii endothelium corneum was summarized, which can provide the scientific basis for the further research and development of Galli gigerii endothelium corneum.

Polypropylene mesh for testicular prothesis implantation: A report of 57 cases / 中华男科学杂志

<p><b>OBJECTIVE</b>To search for an optimum method for testicular prothesis implantation in the treatment of testis loss.</p><p><b>METHODS</b>We retrospectively analyzed the surgical methods and outcomes of 53 cases of terminal prostate cancer and 4 cases of unilateral testicular torsion treated by implantation of testicular prothesis with the polypropylene mesh.</p><p><b>RESULTS</b>The 57 male patients all received testicular prothesis with the polypropylene mesh. All the patients were satisfied with the appearance and size of the scrotum after surgery. No scrotal hematoma, prosthesis infection, or autoimmune disease occurred postoperatively.</p><p><b>CONCLUSION</b>Testis loss is not a rare condition clinically, for the treatment of which surgical implantation of testicular prothesis with the polypropylene mesh can achieve both a fine tissue compatibility and a desirable scrotal appearance.</p>

Observation of prime position and driving zones in process of tuberous root expanding and expression analysis of phytohormone relative genes in Rehmannia glutinosa / 中国中药杂志

In order to study the development characteristics of Rehmannia glutinosa tuberous root expansion and reveal the regulation mechanism of the genes related to hormones in this process, R. glutinosa "wen-85" was used as the experimental material in this study. R. glutinosa tuberous roots of different developmental stages were collected to observe phenotype and tissue morphology using resin semi-thin sections method. The genes related to hormone biosynthesis and response were chosen from the transcriptome of R. glutinosa, which was previously constructed by our laboratory, their expression levels at different development stages were measured by real-time quantitative PCR. The results showed that the root development could be divided into six stages: seeding, elongation, pre-expanding, mid-expanding, late-expanding and maturity stage. The anatomic characteristics indicated that the fission of secondary cambium initiated the tuberous root expansion, and the continuous and rapid division of secondary cambium and accessory cambium kept the sustained and rapid expansion of tuberous root. In addition, a large number oleoplasts were observed in root on the semi-thin and ultra-thin section. The quantitative analysis suggested that the genes related to biosynthesis and response of the IAA, CK, ABA,ethylene, JA and EB were up-regulated expressed, meanwhile, GA synthesis and response genes were down-regulated expressed and the genes of GA negative regulation factors were up-regulated expressed. The maximum levels of most genes expression occurred in the elongation and pre-expansion stage, indicating these two stages were the key periods to the formation and development of tuberous roots. Oleoplasts might be the essential cytological basis for the formation and storage of the unique medicinal components in R. glutinosa. The results of the study are helpful for explanation of development and the molecular regulation mechanism of the tuberous root in R. glutinosa.

Relation of Treg and iNKT cell reconstruction with aGVHD after allogeneic hematopoietic stem cell transplantation in children / 中国实验血液学杂志

This study was aimed to explore the relation of Treg and invariant natural killer T (iNKT) cell reconstruction with acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children. According to the occurrence or absence of aGVHD, 29 pediatric patients who underwent allo-HSCT were firstly divided into two groups non-aGVHD and aGVHD group,then those patients with aGVHD were divided into steroid effective group and steroid resistant group according to their reaction to the steroid treatment. Flow cytometry was used to detect the frequency of Treg cells and iNKT cells in the peripheral blood of the recipients at different time after allo-HSCT(d 15, d 30, d 60, d 90, the time of aGVHD onset and two weeks after steroid treatment). The result showed that the frequencies of Treg cells and the iNKT/T ratio on day 15 in non-aGVHD group were significantly higher than those in the aGVHD group (P < 0.05). It is concluded that a combined monitoring strategy of Treg and iNKT cell reconstruction early after allo-HSCT may facilitate the diagnosis and treatment of aGVHD in children.

Abnormal change of calcium signal system on consecutive monoculture problem of Rehmannia glutinosa / 中国中药杂志

Based on the early transcriptome and digital differentially expressed profiling library construction in consecutive monoculture (two-year culturing) Rehmannia glutinosa, we screened and chose the twelve differentially expressed protein genes which might be related with calcium signal system. The spatiotemporal expression of these genes was measured by the real-time quantitative PCR, and the relative expression values of the genes related with calcium signal system in different development stages and tissues of normal growth (one-year culturing) and succession cropping of R. glutinosa (two-year culturing) was elaborated in detail. In addition, disposed succession cropping of R. glutinosa was treated with different levels of calcium signal blocking agents in order to verify the mode of action of calcium signal system on consecutive monoculture problem in R. glutinosa. Among the twelve genes, two calcium channels away from the cytoplasm were down-regulated expressed, while the ten calcium channels toward the cytoplasm were up-regulated expressed. The results implied that succession cropping caused calcium ions flowing from endoplasmic reticulum to cytoplasm. While the key genes in calcium signal respond components such as CBL, CBP, CIBP, PLC, etc. were down-regulated expressed significantly in succession cropping of R. glutinosa which were disposed with calcium signal blocking agents, the extent of the damage was relieved, and approached the normal growth (one-year culturing) level. This result strongly showed that calcium signal system participated in the perceiving, conducting and magnifying processes of succession cropping obstacles of R. glutinosa.

Adolescents'static behaviors and related factors in Shanghai / 上海预防医学

[Objective] To investigate and analyse the related factors of static behavior among ado-lescents , such as screen time , mild physical activity , moderate and vigorous physical activity , and nutri-tional status. [ Methods] In 2011, multistage sampling was done from 10 classes of three middle schools in three districts in Shanghai;the students filled the questionnaire on their own which recorded all of the activities of one school day and one weekend day .The data was analyzed by general describing analysis , correlation analysis, and Kruskal-Wallis test. [Results] The static time in weekend was 389.19 mi-nutes per day , the screen time was 122 .93 minutes per day , and both were over three times those on one school day .The static time was not related to moderate and vigorous physical activity , but was related to mild physical activity .The difference in mean time before the screen at weekend was statistically significant between obesity group , overweight group , normal group , low weight group and malnutrition group . [ Con-clusion] Adolescents lacked adequate physical activities in their spare time , and behavior before the screen might be related to their poor nutrition status .

Effects of different hepatic inflow occlusion methods on liver regeneration following partial hepatectomy in rats / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the effects of different hepatic inflow occlusion methods on liver regeneration in rats after partial hepatectomy (PH).</p><p><b>METHODS</b>Male Wistar-Furth rats were randomly assigned to three groups: control group, underwent 68% hepatectomy alone; occlusion of portal triad (OPT) group, subjected to occlusion of portal triad under portal blood bypass; and occlusion of portal vein (OPV) group, subjected to occlusion of portal vein under portal blood bypass. Blood flow was occluded for 20, 30, and 40 minutes before 68% hepatectomy. According to the 7-day survival of each group, a same occlusion time T was set. Each group was divided into two subgroups (n = 8), in which animals were killed 3 and 7 days later. Liver regeneration was calculated as a percent of initial liver weight. Immunohistochemistry for proliferating cell nuclear antigen (PCNA) and Ki-67 was performed to quantify proliferating cells. In addition, functional liver volume represented by 99Tc(m)-GSA radioactivity was assessed.</p><p><b>RESULTS</b>The safe tolerance limit time was 30 minutes for OPT group and 40 minutes for OPV group. At 3 days after PH, no significant difference was observed in the regeneration rate of each group (P > 0.05). However, liver radioactive activity, PCNA labeling index, and Ki-67 index of OPV group was significantly higher than those of OPT group (P < 0.05); the latter were similar to those of control group (P > 0.05). At 7 days after PH, no significant difference was observed in all indexes among three groups (P > 0.05).</p><p><b>CONCLUSION</b>Compared with Pringle maneuver, preserving the hepatic artery flow during portal triad blood inflow occlusion can promote remnant liver regeneration early after PH.</p>

Viscoelasticity of porcine acellular dermal matrix / 医用生物力学

Objective To evaluate the viscoelastic properties of porcine acellular dermal matrix (PADM) by comparison and analysis on physical parameters of the skin. Methods Full-thickness skin defects were performed on the back of white rabbits as wound models, and randomly divided these wounds into 3 groups according to different methods of skin grafting: PADM group (autogenous skin and PADM were grafted to the surface of the wound), TS group (autogenous skin was grafted in situ), NS group (normal skin as the control). Experiments on the stress-strain relationship of the implanted skin in the three groups were conducted. Results The curves of stress relaxation, creep, and stress-strain relationship showed that under a given stress, PADM group had the lowest strain, NS group had the highest strain, while the strain of TS group was in between the PADM and NS group. Conclusions The skin viscoelasticity mechanical model is a four-parameter solid model. When the skin wounds are grafted by using PADM which may have poor elasticity, its recovery capacity after deformation is also poor, and this is in agreement with the clinical results.