Diallyl disulfide augments sensitivity of DJ-1 overexpressed human gastric cells to 5-FU / 中国药理学通报

Aim To investigate whether diallyl disul-fide (DADS) augments the sensitivity of DJ-1 (protein/ nucleic acid deglycase) overexpressed human gastric SGC7901 cells to 5-FU (5-fluorouracil). Methods The experimental groups include control group, DADS group, VCR (vincristine) group, VCR + DADS group, DJ-1 group, DJ-1 + DADS group. MTT was used to analyze the effect of DADS on 5 -FU (5 -fluorou- racil) induced proliferation inhibition. Flow cytometry was performed to examine the effect of DADS on cell apoptosis. RT-PCR, Western blot, and immunofluo-rescence were used for determine the effect of DADS on the drug resistance associated gene expression. Results DADS enhanced the proliferation inhibitory effect of 5-FU on DJ-1 overexpressed cells and VCR resistant cells. DADS could induce apoptosis in VCR-resistant cells. DADS downregulated the expression of DJ-1 while inducing apoptosis in DJ-1 overexpressed cells. DJ-1 overexpression upregulated the expression of P-gp (P-glycoprotein), Bcl-2, and XIAP (X-linked inhibitor of apoptosis protein), downregulated the expression of caspase-3. DADS decreased the expression of P-gp, Bcl-2, and XIAP, while increased the expression of caspase-3 in DJ-1 overexpressed cells and VCR-resistant cells. Conclusions DADS can augment the sensitivity of DJ-1 overexpressed cells to 5-FU, which is related to its antagonism against DJ-1 mediated upregula- tion of P-gp, Bcl-2, XIAP, and downregulation of caspase-3.

Research advances in the role of Rab GTPases in Alzheimer's disease / 生理学报

Extracellular deposition of β-amyloid (Aβ) and intracellular hyperphosphorylated tau are the predominant pathological changes in Alzheimer's disease (AD). Increasing evidence demonstrates a critical role of a variety of small GTPases, namely Ras-related proteins (Rabs), in the pathogenesis of AD. As crucial regulators of intracellular membrane trafficking, alteration in Rab protein expression and function represents one of the primary factors contributing to the abnormal membrane trafficking in AD. Additionally, the Rab GTPases are also involved in the development of Aβ, tau and other pathological changes associated with AD. In this article, we conduct a comprehensive review on the primary functions of multiple Rab proteins and their involvement in the pathogenesis of AD.

REEP1 Preserves Motor Function in SOD1G93A Mice by Improving Mitochondrial Function via Interaction with NDUFA4 / 神经科学通报·英文版

A decline in the activities of oxidative phosphorylation (OXPHOS) complexes has been consistently reported in amyotrophic lateral sclerosis (ALS) patients and animal models of ALS, although the underlying molecular mechanisms are still elusive. Here, we report that receptor expression enhancing protein 1 (REEP1) acts as an important regulator of complex IV assembly, which is pivotal to preserving motor neurons in SOD1G93A mice. We found the expression of REEP1 was greatly reduced in transgenic SOD1G93A mice with ALS. Moreover, forced expression of REEP1 in the spinal cord extended the lifespan, decelerated symptom progression, and improved the motor performance of SOD1G93A mice. The neuromuscular synaptic loss, gliosis, and even motor neuron loss in SOD1G93A mice were alleviated by increased REEP1 through augmentation of mitochondrial function. Mechanistically, REEP1 associates with NDUFA4, and plays an important role in preserving the integrity of mitochondrial complex IV. Our findings offer insights into the pathogenic mechanism of REEP1 deficiency in neurodegenerative diseases and suggest a new therapeutic target for ALS.

Impact of adjuvant chemotherapy on prognosis in intrahepatic cholangiocarcinoma patients underwent radical resection / 中华外科杂志

Objectives: To investigate the clinical value of adjuvant chemotherapy(ACT) in patients with intrahepatic cholangiocarcinoma(ICC) who underwent radical resection and to explore the optimal population that can benefit from ACT. Methods: A retrospective cohort study method was adopted. The clinical and pathological data of 685 patients with ICC who underwent curative intent resection in 10 Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected;There were 355 males and 330 females. The age(M(IQR)) was 58(14) years (range: 22 to 83 years). Propensity score matching(PSM) was applied to balance the differences between the adjuvant and non-adjuvant chemotherapy groups. Log-rank test was used to compare the prognosis of the two groups of patients. A Bayesian network recurrence-free survival(RFS) prediction model was constructed using the median RFS time (14 months) as the target variable, and the importance of the relevant prognostic factors was ranked according to the multistate Birnbaum importance calculation. A survival prognostic prediction table was established to analyze the population benefiting from adjuvant chemotherapy. Results: Among 685 patients,214 received ACT and 471 did not receive ACT. A total of 124 pairs of patients were included after PSM, and patients in the ACT group had better overall survival (OS) and RFS than those in the non-ACT group(OS: 32.2 months vs. 18.0 months,P=0.003;RFS:18.0 months vs. 10.0 months,P=0.001). The area under the curve of the Bayesian network RFS prediction model was 0.7124. The results of the prognostic factors in order of importance were microvascular invasion (0.158 2),perineural invasion (0.158 2),N stage (0.155 8),T stage (0.120 9), hepatic envelope invasion (0.090 3),adjuvant chemotherapy (0.072 1), tumor location (0.057 5), age (0.042 3), pathological differentiation (0.034 0), sex (0.029 3), alpha-fetoprotein (0.028 9) and preoperative jaundice (0.008 5). A survival prediction table based on the variables with importance greater than 0.1 (microvascular invasion,perineural invasion,N stage,T staging) and ACT showed that all patients benefited from ACT (increase in the probability of RFS≥14 months from 2.21% to 7.68%), with a more significant increase in the probability of RFS≥14 months after ACT in early-stage patients. Conclusion: ACT after radical resection in patients with ICC significantly prolongs the OS and RFS of patients, and the benefit of ACT is greater in early patients.

Diallyl disulfide downregulates XIAP through miR-7 to inhibit proliferation, migration and invasion of human gastric cancer SGC7901 cells / 中国药理学通报

Aim To investigate whether diallyl disul¬fide ( DADS) downregulates X-linked inhibitor of ap- optosis protein ( XIAP) through miR-7 , inhibiting the proliferation, migration anrl invasion of gastric eaneer SGC7901 eel Is.Methods Gastric eaneer SGC7901 eell line overexpressing XIAP was established.qRT- PCR and Western blot were used to deteet the effeet of DADS on XIAP expression in overexpressed eells.CCK-8 and plate elone formation assay were used to analyze the effeet of DADS on the proliferation of XIAP overexpressing eells.Wound healing and Transwell ex¬periments were employed to analyze the effeets of DADS on the migration and invasion of XIAP overex¬pressing eells.qRT-PCR was used to deteet the effeet of DADS on the expression of miR-7.Negative regula¬ tion of miR-7 on XIAP was verified by using dual lucif- erase reporter gene assay, qRT-PCR ,anrl Western blot.Results XIAP overexpression enhanced the prolifera¬tion , migration and invasion of SGC7901 cells.DADS downregulated XIAP and inhibited the proliferation, mi¬gration and invasion of XIAP overexpressing cells.DADS upregulated miR-7 expression.miR-7 bound and regulated XIAP 3 'UTR directly.Overexpression of miR-7 decreased XIAP expression,while knockdown of miR-7 increased XIAP expression.Conclusion DADS downregulates XIAP through miR-7 to inhibit SGC7901 cell proliferation, migration and invasion.

Purpurin, a anthraquinone induces ROS-mediated A549 lung cancer cell apoptosis via inhibition of PI3K/AKT and proliferation.

OBJECTIVES: In this study, we sought to evaluate purpurin, a natural biomedicine and a potential inhibitor in decreasing the growth rate of lung cancer cells by modulating the role of PI3K/AKT signalling-associated proliferation and apoptosis. METHODS: A549 cells were treated with purpurin (30 µM) for 24 and 48 h incubation, respectively, and it has been analysed for cytotoxicity, ROS-mediated apoptotic staining. Moreover, purpurin-mediated lipid peroxidation and GSH were measured by biochemical estimation. Furthermore, PI3K/AKT signalling-mediated cell proliferation and apoptotic gene expression done were by western blot. KEY FINDINGS: In this study, we observed that purpurin could effectively kill A549 cancer cell lines and leads to cell death, thus conforming increased cytotoxicity, production of ROS-mediated enhancement of lipid peroxidation, nuclear fragmentation and apoptosis. Moreover, the GSH content of A549 cell lines was also diminished after treatment with purpurin. This study demonstrates that purpurin inhibits the phosphorylated PI3K/AKT molecules mediated cyclin-D1 and PCNA, thereby inducing apoptosis by observing increased proapoptotic mediators Bax, cleaved PARP, cytochrome-c, caspase-9 and caspase-3; and decreased Bcl-2 expression in the lung cancer cell lines. CONCLUSION: This result concluded that purpurin eliminates the A549 lung cancer cells by blocking the PI3K/AKT pathway thereby inducing apoptosis.

Chondroprotective effect of Alpinia oxyphylla extract in experimentally induced cartilage degradation in rabbit articular cartilage explants.

Alpinia oxyphylla is a widely used medicinal herb for diarrhea, gastralgia, tumors, hypertention, and cerebrovascular disorders. Here, we evaluated the chondroprotective effect of A. oxyphylla dried fruit ethanol extract (AOE) against cartilage degradation in rabbit articular cartilage explants. Treatment of interleukin-1α (IL-1α) and plasminogen increased degraded collagen release in culture supernatants, but pretreatment of AOE (50, 100, 200 µg/ml) inhibited the collagen release in dose-dependent manner. To examine the mechanism of action of AOE on chondroprotection, the level of matrix metalloproteinases-3 (MMP-3), matrix metalloproteinases-13 (MMP-13), tissue inhibitor of metalloprotease-1 (TIMP-1), and inflammatory mediators like prostaglandin E2 (PGE2 ) and nitric oxide (NO) was evaluated. AOE inhibited upregulation of MMP-3 and MMP-13 and downregulation of TIMP-1 and also reduced increase of PGE2 and NO level induced by exposure of IL-1α and plasminogen. These results indicate that AOE show chondroprotective effect through inhibiting collagen degradation via regulating MMPs, TIMP-1, and inflammatory mediators. PRACTICAL APPLICATIONS: Osteoarthritis (OA) is a one of the most common chronic disorders in elderly persons. Because the regenerative power of joint articular cartilage is very low, treatment of OA is difficult to expect complete recovery. Therefore, there is a need to develop a therapeutic agent that can safely and effectively inhibit the cartilage destruction. For the first time, we exhibited the inhibitory effect of AOE on collagen degradation through regulating MMPs and TIMP-1 in articular cartilage explants. These findings support AOE could be used as herbal therapeutic application for protecting articular cartilage to prevent OA.

Improvement of Figure of Merit Pb(Zr,Ti)O3-Pb(Zn,Ni,Nb)O3-Pb(In,Nb)O3 Piezoelectric Ceramics.

Figure of merit the product of piezoelectric charge constant and the piezoelectric voltage constant-d33 × g33 in piezoelectric energy harvesting systems are critical measures in energy harvester applications. It is difficult to achieve high figure of merit because of the interdependence of d33 and the relative dielectric constant, εr. Until now, the prohibitive amount of effort required to solve this problem has led to it being considered an unsolvable issue. Lead zirconate titanate ceramic, Pb(Zr,Ti)O3, has been reported to exhibit high values of d33 and εr. However, to be employed as piezoelectric energy harvester, a candidate material is required to exhibit both high piezoelectric charge coefficient and high piezoelectric electric voltage coefficient simultaneously. To enhance the figure of merit of Pb(Zr,Ti)O3-based materials, dopants have also been considered. Pb(Zn,Ni,Nb)O3- added Pb(Zr,Ti)O3, Pb(Zr,Ti)O3-Pb(Zn,Ni,Nb)O3 ceramic has been reported to exhibit a high d33 value of 561 pC/N. It's dielectric constant has also been reported to be low at 1898. In this study, Pb(Zr,Ti)O3-Pb(Zn,Ni,Nb)O3-Pb(In,Nb)O3 was investigated in the context of enhancing the figure of merit of Pb(Zr,Ti)O3-based materials. During the proposed process, we increased the corresponding figure of merit by adding Pb(In,Nb)O3 material. Besides exhibiting a low dielectric constant, the Pb(In,Nb)O3 material was also observed to exhibit high d33 × g33 as the proposed doping increased the value of d33 greatly, while maintaining the dielectric constant (Yan, J., et al., 2019. Large engancement of trans coefficient in PZT-PZN energy harvesting system through introducing low εrPIN relaxor. Journal of the European Ceramic Society, 39, pp.2666-2672). Further, we conducted an optimization experiment by controlling the doping concentration and the sintering temperature.

Combination of Red Clover and Hops Extract Improved Menopause Symptoms in an Ovariectomized Rat Model.

Red clover and hops are already known for their alternative menopausal therapies; however, their combination has not yet been studied. This study aimed to evaluate the efficacy of the combination of red clover and hops extract (RHEC) for treating menopausal symptoms for the first time. A high-performance liquid chromatography (HPLC) method for RHEC was developed and validated for the analysis of biochanin A in red clover extract and xanthohumol in hops extract. An in vivo study was conducted using an ovariectomized rat model treated with RHEC (125, 250, and 500 mg/kg, p.o.) for a 12-week test period. Changes in body weight, tail skin temperature (TST), serum lipid profile, bone metabolism, antioxidants, and markers of vasorelaxation and uterus endometrium were evaluated. RHEC significantly inhibited body weight gain and decreased fat weight. Changes in TST associated with flashes were significantly inhibited in the RHEC groups. Other markers related to menopausal symptoms, such as blood lipid profile (total cholesterol and low-density-lipoprotein cholesterol), bone metabolism (serum alkaline phosphatase, osteocalcin, and c-terminal telopeptide type 1), antioxidants (superoxide dismutase and malondialdehyde), and vasorelaxants (endothelin-1 and nitric oxide), were significantly improved after the administration of RHEC. We also confirmed the safety of RHEC through histopathological observation of the endometrium. Our findings demonstrate that RHEC appears to have high potential for comprehensively improving various symptoms of menopause.

28-day repeated oral dose toxicity study of an aqueous extract of Gryllus bimaculatus in sprague-dawley rat.

This study was performed to demonstrate a No Observed Adverse Effect Level (NOAEL) for an aqueous extract of Gryllus bimaculatus. According to other studies, using dried material or extract with ethanol or methanol determined a NOAEL dose of 1000 mg/kg or 5000 mg/kg in rats. Therefore, the Gryllus bimaculatus groups were administered orally at doses of 0, 1000, 2000, and 3000 mg/kg for four weeks. Two-week recovery groups were administered at doses of 0, and 3000 mg/kg. During administration and recovery period, the animals were observed for clinical signs, change of body weight, food consumption, hematology, and clinical chemistry. Rats in each group were periodically sacrificed, and organs were weighed and examined histologically. No difference arose between any of the dosage groups and the control group in clinical signs, histopathological examination, hematology, or clinical chemistry. In conclusion, 3000 mg/kg is a NOAEL dose for Gryllus bimaculatus extracts in Sprague Dawley rats.

Anti-inflammatory and anti-nociceptive activities of Alpinia Oxyphylla Miquel extracts in animal models.

ETHNOPHARMACOLOGICAL RELEVANCE: Alpinia Oxyphylla Miquel is a widely used traditional herbal medicine for the treatment of abdominal pain, intestinal disorders, enuresis, and inflammatory conditions. AIM OF THE STUDY: In this study we aimed to demonstrate the anti-inflammatory and anti-nociceptive effects of Alpinia Oxyphylla Miquel extracts with 50% ethanol (AOE) in animal models. MATERIAL AND METHOD: The anti-inflammatory and nociceptive effects of AOE were estimated in vivo using a carrageenan-induced rat paw edema model, an arachidonic acid-induced mice ear edema model, an acetic acid induced mice writhing test model, and an ex vivo sulfated glycosaminoglycan (GAG) inhibition assay. In vitro inhibition assays for cyclooxygenase (COX) and lipoxygenase (LOX) were performed to determine the IC50 of AOE. RESULTS: Compared with the control, AOE caused a significant inhibition of paw edema, ear thickness, and abdominal constriction in animals. Compared with untreated explants exposed to interleukin-l alpha (IL-1α), preoteoglycan degradation by IL-1α was inhibited (18.2%-82.0%) in explants treated with AOE (50-400 µg/ml). In vitro, IC50 values of AOE were 299.87, 199.07, and 170.29 µg/ml for COX-1, COX-2, and 5-LOX respectively. CONCLUSIONS: These data demonstrate the potent anti-inflammatory and analgesic effects of AOE and suggest AOE to be useful for the treatment of osteoarthritis and/or associated symptoms.

The impact of containment measures and air temperature on mitigating the transmission of COVID-19: a novel data-based comprehensive modeling analysis

Early non-pharmaceutical interventions (NPIs) are crucial to prevent and control of COVID-19 pandemic. We established a stochastic non-classical SEIR NPIs model (ScEIQRsh) which can quantify the three kinds of NPIs measures simultaneously to mimic the clustered intra-family or intra-acquaintance spreading pattern of COVID-19 under the effective integrated NPIs in Mainland China. Model simulation demonstrated that measures to diminish contactable susceptible (Sc), such as home confinement, travel constraint, social distancing etc. and measures to avoid delay of diagnosis and hospitalized isolation ({eta}) were more effective but consumptive than contact tracing ({kappa}, {rho}). From fitted model by MCMC method, the proportion of asymptomatic infectors was 14.88% (IQR 8.17%, 25.37%). The association between air temperature and the fitted transmission rate ({beta}) of COVID-19 suggests that COVID-19 pandemic would be seasonal with the optimal temperature range of 5{degrees}C-14{degrees}C and peak of 10{degrees}C for spreading, and vaccine is indispensable to ultimate prevention COVID-19.

Improved Multilayered (Bi,Sc)O3-(Pb,Ti)O3 Piezoelectric Energy Harvesters Based on Impedance Matching Technique.

As a piezoelectric material, (Bi,Sc)O3-(Pb,Ti)O3 ceramics have been tested and analyzed for sensors and energy harvester applications owing to their relatively high Curie temperature and high piezoelectric coefficient. In this work, we prepared optimized (Bi,Sc)O3-(Pb,Ti)O3 piezoelectric materials through the conventional ceramic process. To increase the output energy, a multilayered structure was proposed and designed, and to obtain the maximum output energy, impedance matching techniques were considered and tested. By varying and measuring the energy harvesting system, we confirmed that the output energies were optimized by varying the load resistance. As the load resistance increased, the output voltage became saturated. Then, we calculated the optimized output power using the electric energy formula. Consequently, we identified the highest output energy of 5.93 µW/cm2 at 3 MΩ for the quadruple-layer harvester and load resistor using the impedance matching system. We characterized and improved the electrical properties of the piezoelectric energy harvesters by introducing impedance matching and performing the modeling of the energy harvesting component. Modeling was conducted for the piezoelectric generator component by introducing the mechanical force dependent voltage sources and load resistors and piezoelectric capacitor connected in parallel. Moreover, the generated output voltages were simulated by introducing an impedance matching technique. This work is designed to explain the modeling of piezoelectric energy harvesters. In this model, the relationship between applied mechanical force and output energy was discussed by employing experimental results and simulation.

Anatomic basis and clinical application of perforator flap thinning of posterior tibial artery / 中华显微外科杂志

Objective To explore the anatomic basis of the thinning of the free posterior tibial artery perforator flaps and the clinical effect of repairing wound on hand or foot due to trauma.Methods From November,2016 to December,2017,10 cases of lower extremity cadaver specimens perfused with red ralex were dissected,which were perfused through the amputated femoral artery.Five of them were left and the rest were right.All cases were males.The number,diameter,branches and distribution of the perforator was observed.From September,2012 to September,2017,there were 13 cases of clinical application,which were 5 cases of hand wound and 8 cases of foot wound.The size of the wound was 3.0 cm × 2.0 cm to 6.0 cm × 4.0 cm,and the flap area was 3.5 cm × 2.2 cm to 6.5 cm × 4.5 cm.The repairing procedure was suitable for the wound associated with tendon,bone,joint capsule exposure.Results The number of posterior tibial artery perforating branches that more than 0.50 mm in diameter was 4 to 6,and the mean diameter was (0.87±0.26) mm.The perforating branch penetrated into the fat layer and was divided into 3 layers of vascular network:deep fat vascular network,superficial fat vascular network and subdermal vascular network.The perforating branch was located according to the positional relationship from deep to shallow,and vessel diameter become smaller step by step.The perforating branch trunk gave off branches to the deep vascular network,and the superficial vascular network had the same origin or shared with the deep blood vessels.The subdermal vascular network issued from the superficial vascular network or directly from the perforating branch trunk.There was no or few communicating branch between the deep vascular network and superficial ones,besides the vessel pedicle.So trimming deep fat layer will not affect the blood supply of superficial vascular network and neither will affect the flap blood supply.Most of the deep fat tissue was trimmed in 13 cases.The superficial and subdermal fat vascular network was preserved,and the same to the trunk and branches of the pedicle.All the flaps survived.Of which,1 appeared arterial crisis on the 2nd day after operation,and relieved by the local injection of papaverine.There was 1 case of venous crisis on the 3rd day,and improved by stitches,local release of congestion.Followed-up time was ranged from 2 to 12 months.All flaps were soft with good blood supply and good appearance,and did not need a second thinning surgery.Flaps restored the protective feeling 6 months later.Conclusion The microdissection of perforator flap of posterior tibial artery provides a theoretical basis for the perforator flap thinning,and the thinning of perforator flap is a good method to repair the appearance and function of the wound after foot and hand injuries.

Cross-sectional study on clinic behavior and therapeutic status of patients with psoriatic arthritis in multi-center / 北京大学学报(医学版)

OBJECTIVE@#To investigate and analyse the features of treatment behavior and standardized therapeutic status of patients with psoriatic arthritis (PsA).@*METHODS@#Out patients diagnosed with PsA in People's Hospital of Peking University, Haidian Hospital, People's Hospital of Jianyang City, Central Hospital of Xinxiang City, Integrated Traditional Chinese and Western Medicine Hospital of Cangzhou City, The Third Hospital of Hebei Medical University from February to June 2018 were enrolled in this investigation. The data including gender, age of onset, course of disease, site of first consulting department, time of the first visit and definite diagnosis, follow-up interval, and use of conventional disease modifying anti-rheumatic drugs (cDMARDs) and biological DMARDs (BioDMARDs) were collected and analyzed.@*RESULTS@#In the cross-sectional study, 133 PsA patients were investigated. The mean age of onset was (47±11) years, the male to female ratio was 1.3:1, and mean disease duration was (16±8) years. Rheumatology department was the most common site of first hospital visit (37.6%, 50/133). Orthopedics department and dermatological department were visited by 24.1% (32/133) and 23.3% (31/133), respectively. Ratio of definite diagnosis was the highest in rheumatology department which was 78% (39/50). The ratio of definite diagnosis of dermatological department was the second highest, which was 19.4% (6/31). The mean definite diagnosed time was 7.6 months since the first visit of PsA patients, and diagnosed time was the shortest in rheumatology department, which had statistical significance. 37% PsA patients were treated appropriately in 3 months, 17.3% PsA patients were treated in 3-6 months and 40.2% patients with PsA visited their doctor more than once a year. 48.8% patients hadn't received standardized treatment before visit, and one third patients never received the therapy of DMARDs. Methotrexate was the most commonly used cDMARDs (58.3%), followed by leflunomide (20.5%) and BioDMARDs (19.7%), and biologicals were tumor necrosis factor antagonists.@*CONCLUSION@#In this multi-center study, the first visit department of PsA patients was widely distributed, and most patients were definitely diagnosed in Rheumatology Department. The time of their first visit and definite diagnosis were delayed due to multi factors. Nearly half of the patients did not receive standardized treatment.

Spectrometric analyses of larotaxel and larotaxel liposomes quantification by high performance liquid chromatography / 北京大学学报(医学版)

OBJECTIVE@#Larotaxel is a new chemical structure drug, which has not been marketed worldwide. Accordingly, the standard identification and quantification methods for larotaxel remain unclear. The spectrometric analyses were performed for verifying weight molecular formula, molecular weight and chemical structure of larotaxel. Besides, a quantification method was developed for measuring larotaxel in the liposomes.@*METHODS@#The molecular formula, molecular weight and chemical structure of larotaxel were studied by using mass spectrometry (MS), infra-red (IR), nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-vis) spectrometric techniques. The absorption wavelength of larotaxel was investigated by UV-vis spectrophotometry full-wavelength scanning. Besides, a quantification method was developed by high performance liquid chromatography (HPLC), and then validated by measuring the encapsulation efficacy of larotaxel liposomes.@*RESULTS@#The four spectral characteristics of larotaxel were revealed and the corresponding standard spectra were defined. It was confirmed that larotaxel had the structure of tricyclic diterpenoids, with the molecular formula of C45H53NO14, the molecular weight of 831.900 1, and the maximum absorption wavelength of 230 nm. The quantitative method of larotaxel was established by using HPLC with a reversed phase C18 column (5 μm, 250 mm×4.6 mm), a mobile phase of acetonitrile-water (75:25, volume/volume), and a detection wavelength of 230 nm. The validation study exhibited that the established HPLC method was stable, and had a high recovery and precision in the quantitative measurement of larotaxel in liposomes. In addition, a new kind of larotaxel liposomes was also successfully prepared. The particle size of the liposomes was about 105 nm, with an even size distribution. And the encapsulation efficiency of larotaxel in the liposomes was above 80%.@*CONCLUSION@#The present study offers reference standard spectra of larotaxel, including MS, IR, NMR, and UV-vis, and confirms the molecular formula, molecular weight and chemical structure of larotaxel. Besides, the study develops a rapid HPLC method for quality control of larotaxel liposomes.

Hydroxyapatite Nanorod-Modified Sand Blasted Titanium Disk for Endosseous Dental Implant Applications.

BACKGROUND: Sand blasted titanium (Ti) is commonly used in designing endosseous dental implants due to its biocompatibility and ability to form bonds with bone tissues. However, titanium implants do not induce strong interactions with teeth bones. To increase strong interactions between Ti disk implants and teeth bones, the l-glutamic acid grafted hydroxyapatite nanorods (nHA) were immobilized on albumin modified Ti disk implants (Ti-Alb). METHODS: For modification of Ti disk implants by nHA, the l-glutamic acid grafted nHA was synthesized and then immobilized on albumin modified Ti disk implants. Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope; energy dispersive spectroscopy and confocal laser scanning microscopy were used to confirm the modification of Ti disk implants. The bioactivity of nHA-modified Ti disk implants was evaluated by seeding MC3T3-E1 cells on Ti-nHA implants. RESULTS: Characterization techniques have confirmed the successful modification of Ti disk implants by l-glutamic acid grafted nHA. The nHA-modified Ti disk implants have shown enhanced adhesion, proliferation and cytotoxicity of MC3T3-E1 cells in comparison to pristine Ti implants. CONCLUSIONS: The modification of Ti implants by l-glutamic acid grafted nHA has produced highly osteogenic Ti disk plants in comparison to pristine Ti disk implants due to the formation of bioactive surfaces by hydroxyapatite nano rods on Ti disk implants. Ti-nHA disk implants showed enhanced adhesion, proliferation, and MC3T3-E1 cells viability in comparison to pristine Ti disk implants. Thus nHA might be to be useful to enhance the osseointegration of Ti implants with teeth bones.

Implantation strategy of tissue-engineered liver based on decellularized spleen matrix in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the optimal implantation strategy of tissue-engineered liver (TEL) constructed based on decellularized spleen matrix (DSM) in rats.</p><p><b>METHODS</b>DSM was prepared by freeze-thawing and perfusion with sodium dodecyl sulfate (SDS) of the spleen of healthy SD rats. Primary rat hepatocytes isolated using modified Seglen 2-step perfusion method were implanted into the DSM to construct the TEL. The advantages and disadvantages were evaluated of 4 transplant strategies of the TEL, namely ectopic vascular anastomosis, liver cross-section suture transplantation, intrahepatic insertion and mesenteric transplantation.</p><p><b>RESULTS</b>The planting rate of hepatocytes in the DSM was (74.5∓7.7)%. HE staining and scanning electron microscopy showed satisfactory cell status, and immunofluorescence staining confirmed the normal expression of ALB and G6Pc in the cells. For TEL implantation, ectopic vascular anastomosis was difficult and resulted in a mortality rate of 33.3% perioperatively and massive thrombus formation in the matrix within 6 h. Hepatic cross-section suture failed to rapidly establish sufficient blood supply, and no viable graft was observed 3 days after the operation. With intrahepatic insertion method, the hepatocytes in the DSM could survive as long as 14 days. Mesenteric transplantation resulted in a hepatocyte survival rate of (38.3+7.1)% at 14 days after implantation.</p><p><b>CONCLUSION</b>TEL constructed based on DSM can perform liver-specific functions with a good cytological bioactivity. Mesenteric transplantation of the TEL, which is simple, safe and effective, is currently the optimal transplantation strategy.</p>

Hydroxyapatite Nanorod-Modified Sand Blasted Titanium Disk for Endosseous Dental Implant Applications

BACKGROUND: Sand blasted titanium (Ti) is commonly used in designing endosseous dental implants due to its biocompatibility and ability to form bonds with bone tissues. However, titanium implants do not induce strong interactions with teeth bones. To increase strong interactions between Ti disk implants and teeth bones, the L-glutamic acid grafted hydroxyapatite nanorods (nHA) were immobilized on albumin modified Ti disk implants (Ti-Alb). METHODS: For modification of Ti disk implants by nHA, the L-glutamic acid grafted nHA was synthesized and then immobilized on albumin modified Ti disk implants. Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope; energy dispersive spectroscopy and confocal laser scanning microscopy were used to confirm the modification of Ti disk implants. The bioactivity of nHA-modified Ti disk implants was evaluated by seeding MC3T3-E1 cells on Ti-nHA implants. RESULTS: Characterization techniques have confirmed the successful modification of Ti disk implants by L-glutamic acid grafted nHA. The nHA-modified Ti disk implants have shown enhanced adhesion, proliferation and cytotoxicity of MC3T3-E1 cells in comparison to pristine Ti implants. CONCLUSION: The modification of Ti implants by L-glutamic acid grafted nHA has produced highly osteogenic Ti disk plants in comparison to pristine Ti disk implants due to the formation of bioactive surfaces by hydroxyapatite nano rods on Ti disk implants. Ti-nHA disk implants showed enhanced adhesion, proliferation, and MC3T3-E1 cells viability in comparison to pristine Ti disk implants. Thus nHA might be to be useful to enhance the osseointegration of Ti implants with teeth bones.