HHV8-unrelated primary effusion lymphoma in a patient with HBV-related liver cirrhosis: A case successfully treated with rituximab and lenalidomide.

Human herpesvirus type 8 (HHV-8) unrelated primary effusion lymphoma (PEL) like lymphoma (PEL-LL) is an exceedingly rare non-Hodgkin lymphoma with no characteristic symptoms and consensus on the optimal treatment. This case report presents a 55-year-old man with prior HBV-related Child-Pugh B liver cirrhosis and developing activity-related dyspnea. A moderate amount of pleural effusion was identified without tumor masses, and cytological studies confirmed a diagnosis of PEL-LL. The patient received rituximab and lenalidomide, albeit with HBV infection, and is currently on maintenance therapy with resolving symptoms but without HBV reactivation. Hence, the R2 protocol (rituximab and lenalidomide) might be clinically effective and safe for PEL-LL patients with HBV infection and Child-Pugh B liver cirrhosis.

Laponite intercalated biomimetic multilayer coating prevents glucocorticoids induced orthopedic implant failure.

Implant failure, which is commonly associated with failure of osseointegration and peri-implant infection, is a severe complication of orthopedic surgery. In particular, the survival rate of implants is significantly decreased in patients using long-term glucocorticoids (GCs). However, the exact molecular mechanism underlying GCs-induced implant loosening, as well as preventive strategies for these patients, is unclear. To address this problem, we performed RNA-sequencing and found that WNT16 was correlated with GCs-induced osteopenia (LogFC = -5.17, p ＜ 0.01). Inspired by the concept of "organic-inorganic" hybrid, we theorized to introduce a bioactive two-dimensional nanosheet into a layer-by-layer (LbL) self-assembly coating to construct a customized implant that targets WNT16. After screening commercially available nanosheets, laponite (LAP) was identified as a cost-effective rescuer for GCs-induced WNT16 inhibition, which was then intercalated into LbL deposition system consisting of quaternized chitosan (QCS) and hyaluronic acid (HA). The hybrid coating (QCS/HA/LAP) showed micrometer thickness and improved hydrophilicity and interface roughness. Furthermore, QCS/HA/LAP coated polyetheretherketone (PEEK) implant enhanced cell viability, adhesion, and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), and promoted osteointegration of PEEK in GCs-treated rats by targeting the WNT16/ß-catenin axis. The assembled QCS has proven antibacterial properties, and the hybrid coating exerted potent detrimental effects against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), both in vitro and in vivo. Taken together, these results suggest that QCS/HA/LAP coating has great potential for use in implants customization, and has synergistic pro-osteogenic and antibacterial effects that help prevent implant failure in GCs-treated patients.

Clinical outcomes of newly diagnosed primary central nervous system lymphoma treated with zanubrutinib-based combination therapy.

BACKGROUND: High-dose methotrexate (HD-MTX) combined with other chemotherapeutic agents is an effective treatment for patients with newly diagnosed primary central nervous system lymphoma (PCNSL); however, some patients have adverse reactions. AIM: To retrospectively evaluate disease outcomes and mutational profiles in newly diagnosed PCNSL patients treated with a zanubrutinib/HD-MTX combination regimen. METHODS: Nineteen newly diagnosed PCNSL patients were treated with zanubrutinib/HD-MTX until disease progression, intolerable toxicities, or physician/patient-directed withdrawal. Safety and efficacy were assessed per the CTCAE v5.0 and RECIST v1.1 criteria, respectively. The primary endpoint was the objective response rate (ORR), and the secondary endpoints were progression-free survival, overall survival (OS), and safety. RESULTS: The median follow-up duration was 14.7 mo (range, 3.9-30 mo). The ORR for all patients was 84.2%, and 2-year progression-free- and OS rates were 75.6% and 94.1%, respectively. All patients completed the induction phase, and nine patients underwent autologous stem cell transplantation as consolidation therapy, resulting in an ORR of 88.9%. Ten patients received zanubrutinib as maintenance therapy and achieved an ORR of 80%. All patients showed an acceptable safety profile. The sequencing results for cerebrospinal fluid (CSF) and tumor tissue showed that PIM1 mutations were the most frequent genetic alterations. Circulating tumor DNA was correlated with disease relapse and response. CONCLUSION: Our empirical observations demonstrated that the combination of zanubrutinib with HD-MTX yielded a marked clinical response and tolerability among newly diagnosed PCNSL patients. Non-invasive CSF liquid biopsy profiling may be feasible for evaluating treatment response and tumor burden.

Decellularized tilapia fish skin: A novel candidate for tendon tissue engineering.

The poor regenerative ability of injured tendon tissues remains a clinical challenge. However, decellularized extracellular matrix (ECM) combined with stem cells shows promise. In contrast to bovine and porcine ECM, marine-derived decellularized ECM has several advantages; it is easily obtained, poses less biological risk, and is not contraindicated on religious grounds. This study successfully fabricated decellularized tilapia fish skin (DTFS) with copious preserved collagen fibers and natural pore structures. The outer layer is smooth and dense, while the inner layer has a soft structure with a rough surface. After crosslinking with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS), crosslinked DTFS (C-DTFS) showed improved mechanics in dry and wet conditions. In vitro, the leach liquor of crosslinked DTFS showed no cytotoxicity and promoted migration and tenonic differentiation of tendon-derived stem cells (TDSCs). Meanwhile, TDSCs seeded in the inner surface of DTFS maintained viability, differentiated, and exhibited spreading. Furthermore, cell-seeded scaffolds guided the regeneration of tendon tissue in a rat Achilles tendon defect model. Our results suggest that DTFS combined with TDSCs is a novel and promising therapeutic option for tendon tissue engineering.

Sulfated alginate oligosaccharide exerts antitumor activity and autophagy induction by inactivating MEK1/ERK/mTOR signaling in a KSR1-dependent manner in osteosarcoma.

Alginate oligosaccharide (AOS) has the function to inhibit tumor progression and the sulfated modification can enhance the antitumor activity. To date, the function and mechanism of sulfated AOS (AOS-SO4) in tumors remain largely elusive. We prepared AOS by the enzymatic degradation of alginate, collected AOS-SO4 by sulfating following the canonical procedure. Using these materials, in vitro assays showed that both AOS and AOS-SO4 elicited antitumor effects in osteosarcoma cells. Sulfated modification significantly enhanced the antitumor activity. In addition, AOS-SO4 had obvious effects on cell cycle arrest, apoptosis, and autophagy induction in vitro and in vivo. Mechanistically, we observed that AOS-SO4 treatment triggered proapoptotic autophagy by inhibiting MEK1/ERK/mTOR signaling. The ERK activator reversed AOS-SO4-induced autophagy. More importantly, we found that KSR1 interacted with MEK1 and functioned as a positive regulator of MEK1 protein in osteosarcoma cells. High KSR1 expression was significantly associated with poor survival in osteosarcoma patients. Together, these results suggest that AOS-SO4 has a better antitumor effect in osteosarcoma by inhibiting MEK1/ERK/mTOR signaling, which is KSR1-dependent; thus, AOS-SO4 can be a new potential therapeutic candidate for the treatment of osteosarcoma.

[Clinical Efficacy of High Dose Methotrexate, Temozolomide and Rituximab in the Treatment of Patients with Primary Central Nervous System Lymphoma].

OBJECTIVE: To investigate the clinical efficacy of high dose methotrexate (HD-MTX), temozolomide (TMZ), and rituximab (R) in the treatment of patients with primary central nervous system lymphoma (PCNSL). METHODS: Clinical data of patients with PCNSL diagnosed and treated in Guangdong Provincial People's Hospital from February 2010 to May 2017 were collected. First, patients were given 6-8 cycles of MTX (3.5 g/m2) for induction treatment, and then 12 cycles of TMZ (150 mg/m2) for maintenance treatment. The day before induction treatment, patients were given rituximab 375 mg/m2 according to their economic status. A retrospective cohort study was performed on patients receiving HD-MTX+TMZ or HD-MTX+TMZ+R to analyze the efficacy and survival. RESULTS: There were 42 patients enrolled in the study, 17 cases in HD-MTX+TMZ group and 25 cases in HD-MTX+TMZ+R group. The median PFS and OS times in HD-MTX+TMZ+R group were 56.7 months and N/A, respectively, while, 7.3 months and 34.7 months in HD-MTX+TMZ group, respectively. In addition, there was no significant difference in median survival between patients who received TMZ maintenance therapy and those who were only actively monitored. During the induction period, all the patients had grade 1-2 nausea and vomiting, while in the consolidation treatment period, no grade 3/4 toxicity was observed. CONCLUSION: The combination of HD-MTX+TMZ+R in the treatment of PCNSL patients shows a definite short-term effect, which can increase the survival rate of the patients. The side effects are mild, and the patients can generally tolerate.

Primary cardiac lymphoma: the management and outcome of a single-centre cohort of 22 patients.

BACKGROUND: The incidence of primary cardiac lymphoma (PCL) is increasing, but the optimal management approach remains unclear. We assessed the clinical characteristics of a single-centre cohort with the goal of determining the optimal management approach. The treatment outcomes and prognostic factors are reported. MATERIAL AND METHODS: All PCL patients were diagnosed via biopsy guided by whole-body imaging (positron emission tomography/computed tomography [PET/CT] and/or contrast-enhanced CT]. Curative therapy involved either surgery or prephase steroids followed by definitive immunochemotherapy, depending on the histological type. The primary outcomes were overall survival (OS) and progression-free survival (PFS); the secondary outcome was the treatment response. RESULTS: Twenty-two PCL patients (14 males, 8 females; age: 59.5 ± 14.7 years [mean ± S.D.]) were histologically confirmed to have diffuse large B-cell lymphoma (DLBCL; n = 17 [77.3%]), fibrin-associated DLBCL (FA-DLBCL) (n = 4 [18.2%]) and Burkitt lymphoma (n = 1 [4.5%]). Seven patients underwent cardiotomy (three for biopsy, four with curative intent). The median and longest follow-up periods were 16.3 and 180.0 months, respectively. The 16 patients who received curative therapy (complete response [CR], n = 15 [93.8%]; partial response [PR], n = 1 [6.2%]) showed better survival than those who did not (5-year OS: 83.0 ± 11.3% vs. 0%; hazard ratio [HR]: 0.025[95% confidence interval, CI: 0.003-0.187], p < 0.001); 5-year PFS: 78.7 ± 11.0% vs. 0%, HR= 0.010[0.001-0.093], p < 0.001). The left ventricular ejection fractions (LVEF) before and after definitive treatment was 63.6 ± 2.4% and 64.6 ± 4.5%, respectively (p = 0.275, power = 0.318). Extrapericardial lesions were associated with poorer survival (5-year OS: 40.0 ± 29.7% vs. 100%, p = 0.027; 5-year PFS:40.0 ± 21.9% vs. 100%, p = 0.010). CONCLUSIONS: Whole-body imaging is essential for diagnosis and prognosis. Curative therapy provided reasonable outcomes and survival; extrapericardial lesions were associated with a poorer treatment response.

Chitooligosaccharides inhibit tumor progression and induce autophagy through the activation of the p53/mTOR pathway in osteosarcoma.

Osteosarcoma is the most common primary sarcoma of bone. The use of Chitooligosaccharide (COS) as a drug carrier is an emerging new strategy for cancer therapy. However, the application of COS in osteosarcoma has not been reported. Here, we investigated the influence of COS on osteosarcoma, and suggested the underlying mechanism. Initially, we obtained COS with a low-degree-polymerized (DP = 2-6) by enzymatic hydrolysis. Using these COS materials, in vitro assays showed that COS elicited the anti-tumor activity against osteosarcoma cells. We found that COS had significant effects on cell growth, metastasis inhibition, apoptosis and autophagy induction, and triggered pro-apoptosis autophagy through p53/mTOR signaling pathway in osteosarcoma cells. In addition, the COS also inhibited tumor growth and metastasis in an osteosarcoma xenograft model in vivo. Finally, we showed that COS could increase sensitivity to chemotherapy of cisplatin in vitro. Thus, we provide experimental evidence to demonstrate that COS has anti-tumor effect on osteosarcoma, and COS can be a new potential therapeutic candidate for the treatment of osteosarcoma.

Well-dispersed platelet lysate entrapped nanoparticles incorporate with injectable PDLLA-PEG-PDLLA triblock for preferable cartilage engineering application.

Platelet lysate (PL) as a cost-effective cocktail of growth factors is an emerging ingredient in regenerative medicine, especially in cartilage tissue engineering. However, most studies fail to pay attention to PL's intrinsic characteristics and incorporate it directly with scaffolds or hydrogels by simple mixture. Currently, the particle size distribution of PL was determined to be scattered. Directly introducing PL into a thermosensitive poly(d,l-lactide)-poly(ethylene glycol)-poly(d,l-lactide) (PLEL) hydrogel disturbed its sol-gel transition. Electrostatic self-assembly heparin (Hep) and ε-poly-l-lysine (EPL) nanoparticles (NPs) were fabricated to improve the dispersity of PL. Such PL-NPs-incorporated PLEL gels retained the initial gelling capacity and showed a long-term PL-releasing ability. Moreover, the PL-loaded composite hydrogels inhibited the inflammatory response and dedifferentiation of IL-1ß-induced chondrocytes. For in vivo applications, the PLEL@PL-NPs system ameliorated the early cartilage degeneration and promoted cartilage repair in the late stage of osteoarthritis. RNA sequencing analysis indicated that PL's protective effects might be associated with modulating hyaluronan synthase 1 (HAS-1) expression. Taken together, these results suggest that well-dispersed PL by Hep/EPL NPs is a preferable approach for its incorporation into hydrogels and the constructed PLEL@PL-NPs system is a promising cell-free and stepwise treatment option for cartilage tissue engineering.

A free-standing multilayer film as a novel delivery carrier of platelet lysates for potential wound-dressing applications.

Great efforts have been made to develop suitable bioactive constructs that release growth factors (GFs) in a controlled manner for tissue-regeneration applications. Platelet lysates (PLs) are an affordable source of multiple GFs and other proteins, and show great potential in the wound-healing process. Herein, poly-l-lysine (PLL) and hyaluronic acid (HA) were applied to build free-standing polyelectrolyte multilayer films (PEMs) using the PH-amplified layer-by-layer self-assembly method. Molecular simulations were performed, which showed that in the end layer of PEMs, HA was more attractive to PLs than was PLL. The HA/PLL films constructed with or without 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) cross-linking both absorbed PLs successfully, exhibiting high hydrophilicity and GF absorptivity. The release profile of the EDC30 film lasted up to 2 weeks, and PL-loaded films supported cell proliferation, adhesion, migration, and angiogenesis in vitro. Moreover, due to sustained delivery of PLs, the membranes (especially the crosslinked film) helped to promote granulation-tissue formation, collagen deposition, and neovascularization in the region of the defect, resulting in rapid re-epithelialization and regeneration of skin. Mechanistically, the beneficial effects of a PL-loaded PEM coating might be related to activation of the hypoxia-inducible factor-1(Hif-1α)/vascular endothelial growth factor (VEGF) axis. As an off-the-shelf and cell-free treatment option, these biomimetic multilayers have great potential for use in the fabrication of devices that allow stable incorporation of PLs, thereby exerting synergistic effects for efficient wound healing.

A decellularized scaffold derived from squid cranial cartilage for use in cartilage tissue engineering.

Decellularized cartilage scaffold (DCS) is an emerging substitute for cartilage defect application. However, it is hard to preserve an intact structure of such scaffolds derived from terrestrial animals, because of their dense and compact constitution. In contrast, squid (Dosidicus gigas) cranial cartilage, which possesses a relatively loose structure, could be easily decellularized using mild conditions and it retains the original microstructures of extracellular matrix (ECM). Herein, decellularized squid cranial cartilage scaffold (DSCS) was fabricated successfully after substantially removing the cells, which contained abundant ECM components (proteoglycans and type II collagen). Microscopic structure results showed that the DSCS possesses a relatively smooth and dense surface with a favorable interconnected inner porous structure for cell growth. DSCS exhibited excellent biomechanics and hydrophilicity. In vitro experiments indicated that the scaffold extracts were not toxic to cells, and were amenable to chondrocyte migration. Meanwhile, chondrocytes seeded in DSCS could maintain a favorable viability and present a spreading morphology. Furthermore, the in vivo experiments revealed that both cell-free scaffold and cell-laden scaffold exert promotive effects for the regeneration of cartilage in a full-thickness rabbit cartilage defect model. Taken together, these results suggested that DSCS presents a novel and promising cell-free therapeutic choice for cartilage tissue engineering.

Efficacy of enteric-coated tilmicosin granules in pigs artificially infected with Actinobacillus pleuropneumoniae serotype 2.

BACKGROUND: Porcine infectious pleuropneumonia caused by Actinobacillus pleuropneumoniae (App) is one of the most serious infectious diseases in pigs and has brought huge economic losses to the world pig industry. The aim of this trial was to evaluate the effect of enteric-coated tilmicosin granule in the treatment and control of artificial infection of App. METHODS: Sixty Duroc and Yorkshire crossbred pigs (50 of which were artificially infected) were divided into six groups: BCG (Blank control group), ICG (Infection-only control group), HDG (High-dose enteric-coated tilmicosin granules), MDG (Medium-dose enteric-coated tilmicosin granules), LDG (Low-dose enteric-coated tilmicosin granules) and TPG (Tilmicosin premix drug control group). The cure rate, mortality, clinical respiratory score, body temperature score, weight gain, lung score and so on were recorded. RESULTS: The cure rate of HDG and MDG was as high as 90%, the mortality was 10%, and the clinical signs recovered quickly. CONCLUSION: The results showed that enteric-coated tilmicosin granules had obvious therapeutic effect on artificial infection, which could reduce the damage caused by the disease and reduce the mortality.

Nanofat-derived stem cells with platelet-rich fibrin improve facial contour remodeling and skin rejuvenation after autologous structural fat transplantation.

Traditional autologous fat transplantation is a common surgical procedure for treating facial soft tissue depression and skin aging. However, the transplanted fat is easily absorbed, reducing the long-term efficacy of the procedure. Here, we examined the efficacy of nanofat-assisted autologous fat structural transplantation. Nanofat-derived stem cells (NFSCs) were isolated, mechanically emulsified, cultured, and characterized. Platelet-rich fibrin (PRF) enhanced proliferation and adipogenic differentiation of NFSCs in vitro. We then compared 62 test group patients with soft tissue depression or signs of aging who underwent combined nanofat, PRF, and autologous fat structural transplantation to control patients (77 cases) who underwent traditional autologous fat transplantation. Facial soft tissue depression symptoms and skin texture were improved to a greater extent after nanofat transplants than after traditional transplants, and the nanofat group had an overall satisfaction rate above 90%. These data suggest that NFSCs function similarly to mesenchymal stem cells and share many of the biological characteristics of traditional fat stem cell cultures. Transplants that combine newly-isolated nanofat, which has a rich stromal vascular fraction (SVF), with PRF and autologous structural fat granules may therefore be a safe, highly-effective, and long-lasting method for remodeling facial contours and rejuvenating the skin.

EFFICACY AND SAFETY OF BAN HUANG ORAL LIQUID FOR TREATING BOVINE RESPIRATORY DISEASES.

BACKGROUND: Ban Huang oral liquid was developed as a veterinary compound preparation by the Lanzhou Institute of Husbandry and Pharmaceutical Sciences of the Chinese Academy of Agricultural Sciences (CAAS). The purpose of this study was to determine whether the oral liquid preparation of traditional Chinese medicine, Ban Huang, is safe and effective for treating respiratory diseases in cattle. MATERIALS AND METHODS: Acute oral toxicity experiments were conducted in Wistar rats and Kunming mice via oral administration. The minimum inhibitory concentration of the drug against Mycoplasma bovis in vitro with the double dilution method was 500 mg/mL, indicating good sensitivity. The results of laboratory pathogen testing, analysis of clinical symptoms, and analysis of pathological anatomy were combined to diagnose bovine respiratory diseases in 147 Simmental cattle caused by mixed infections of M. bovis, bovine respiratory syncytial virus, bovine parainfluenza virus type 3, and Mannheimia haemolytica. These cattle were randomly divided into three groups: drug treatment group 1 (treated via Tilmicosin injection), drug treatment group 2 (treated with Shuang Huang Lian oral liquid combined with Tilmicosin injection), and drug treatment group 3 (treated with Ban Huang oral liquid combined with Tilmicosin injection). Treatment effects were observed within 7 days. RESULTS: The results showed no toxicity and a maximum tolerated dose greater than 20 g/kg BW. For the 87 cattle in drug-treatment group, the cure rate was 90.80%, whereas the response rate was 94.25%. The cure rate of drug treatment group was increased by 14.13% in comparison with that of drug control group 1 and by 7.47% in comparison with that of drug control group 2 (both P < 0.05). CONCLUSION: This study demonstrates that Ban Huang oral liquid is a safe and effective treatment for bovine respiratory diseases, especially for mixed infection caused by M. bovis, bacteria, and viruses.

Determination of antibacterial agent tilmicosin in pig plasma by LC/MS/MS and its application to pharmacokinetics.

A rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify tilmicosin in pig plasma. Plasma samples were prepared by liquid-liquid extraction. Chromatographic separation was achieved on a C18 column (2.1 × 30 mm, 3.5 µm) using acetonitrile-water (90:10, v/v; water included 0.1% formic acid) as the mobile phase. Mass detection was carried out using positive electrospray ionization in multiple reaction monitoring mode. The calibration curve was linear from 0.5 to 2000 ng/mL (r2 = 0.9998). The intra- and inter-day accuracy and precision were within the acceptable limits of ±10% for all tilmicosin concentrations. The recoveries ranged from 95 to 99% for the three tested concentrations. The LC-MS/MS method described herein was simple, fast and less laborious than other methods, achieved high sensitivity using a small sample volume, and was successfully applied to pharmacokinetic studies of tilmicosin enteric granules after oral delivery to pigs. In comparison with tilmicosin premix, tilmicosin enteric granules slowed the elimination rate of tilmicosin, prolonged its period of action and significantly improved its bioavailability.

[Silymarin Protects Umbilical Cord-Derived Mesenchymal Stem Cells against Apoptosis Induced by Serum-Deprivation].

OBJECTIVE: To investigate the protection of silymarin against the human mesenchymal stem cell (MSC) apoptosis induced by serum deprivation and its underlying mechanism. METHODS: Human umbilical cord MSCs were cultured in the absence of serum, and the silymain of different concentration (1-10 µg/ml) was added into the medium. MTT test was performed to observe the cell proliferation status. After being cultured for 72 hours, the cells were collected, and flow cytometry with Annexin-V-PI double-staining was used to detect the apoptotic cells from the control and silymarin-treated groups. Furthermore, the intracellular contents of BAX and BCL-2 were detected by Western blot for exploring the potential mechanism. RESULTS: The silymarin promoted the proliferation of human UC-MSCs in a dose-dependent manner, reaching its maximal at a dose of 5 µg/ml. Moreover, silymarin could inhibit the serum deprivation-induced apoptosis of MSCs and, the inhibitory rate reached up to 30% when it was added at a concentration of 5 µg/ml. The content of intracellular BAX was obviously elevated after serum-deprivation treatment, and this increase could be blunted by the addition of silymarin. Meanwhile, the content of BCL-2 was not obviously changed. CONCLUSION: The silymarin can stimulate MSC growth and inhibit the apoptosis of MSCs probably by the mitochondria pathway.

Determination and pharmacokinetic studies of artesunate and its metabolite in sheep plasma by liquid chromatography-tandem mass spectrometry.

A rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneous quantify artesunate and its metabolite in sheep plasma. The plasma samples were prepared by liquid-liquid extraction. Chromatographic separation was achieved on a C18 column (250×4.6mm, 5µm) using methanol: water (60:40, v/v) (the water included 1mM ammonium acetate, 0.1% formic acid, and 0.02% acetic acid) as the mobile phase. Mass detection was carried out using positive electrospray ionization in multiple reaction monitoring mode. The calibration curve was linear from 1ng/mL to 400ng/mL (r(2)=0.9992 for artesunate, r(2)=0.9993 for its metabolite). The intra- and inter-day accuracy and precision were within the acceptable limits of ±10% at all concentrations for both artesunate and its metabolite. The recoveries ranged from 92% to 98% at the three concentrations for both. In summary, the LC-MS/MS metho described herein was fully successfully applied to pharmacokinetic studies of artesunate nanoemulsion after intramuscular delivery to sheep.

[Investigation on the internalization pathway of microparticles into human umbilical cord endothelial cells].

OBJECTIVE: To investigate the mechanisms underlying the incorporation of microparticles(MP) derived from human bone marrow mesenchymal stem cells (MSCs) into human umbilical cord endothelial cells (HUVECs). METHODS: MPs were isolated from the supernatants of MSCs which had exposed to a hypoxia/serum-deprivation condition. Electron microscope was used to identify the MPs. The surface molecule profile was evaluated with the bead-based flow cytometry technique. The expression level of the phosphatidylserine receptor (PSR) was detected by immunofluorescence cytochemistry. MPs were co-cultured with HUVECs in the presence or absence PSR-antibody, and the internalization of MPs was observed with laser scanning microscopy. RESULTS: The MPs derived from MSCs expressed highly PS, while PSR expressed on the surface of HUVECs. The confocal result revealed that MPs could quickly be uptaken by the endothelial cells, and mainly distributed in the cytoplasm surrounding of the nuclei. The internalization of MPs reduced significantly after PSR specific blockage. CONCLUSION: The reaction between PS on the MP and the PSR of HUVECs plays an important role in the internalization of MSC-MPs.

Determination and pharmacokinetic studies of arecoline in dog plasma by liquid chromatography-tandem mass spectrometry.

A rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of arecoline concentration in dog plasma. Plasma sample was prepared by protein precipitation using n-hexane (containing 1% isoamyl alcohol) with ß-pinene as an internal standard. Chromatographic separation was achieved on an Agilent C18 column (4.6×75mm, 3.5µm) using methanol: 5mM ammonium acetate as the mobile phase with isocratic elution. Mass detection was carried out using positive electrospray ionization in multiple reaction monitoring mode. The calibration curve for arecoline was linear over a concentration range of 2-500ng/mL. The intra-day and inter-day accuracy and precision were within the acceptable limits of ±10% at all concentrations. In summary, the LC-MS/MS method described herein was fully validated and successfully applied to the pharmacokinetic study of arecoline hydrobromide tablets in dogs after oral administration.

Bone marrow mesenchymal stem cell-derived microvesicles protect rat pheochromocytoma PC12 cells from glutamate-induced injury via a PI3K/Akt dependent pathway.

Studies have suggested that mesenchymal stem cells (MSCs) can protect neuronal cells from excitotoxicity, but the underlying mechanisms are still remaining elusive. In the study, we show that microvesicles released by rat bone marrow-derived MSCs (rBMSC-MVs) protect rat pheochromocytoma PC12 cells from glutamate-induced excitotoxicity. BMSC-MVs upregulate Akt phosphorylation and Bcl-2 expression, downregulate Bax expression, and reduce the cleavage of caspase-3 in glutamate-treated PC12 cells. Such protective effects are partially abrogated by inhibiting PI3K, indicating that rBMSC-MVs act via the PI3K/Akt pathway. Transplantation of rBMSC-MVs may, therefore, be a promising strategy to treat cerebral injury or some other neuronal diseases involving excitotoxicity.