Mesenchymal stem cell-derived small extracellular vesicles in the treatment of human diseases: Progress and prospect.

Mesenchymal stem cells (MSCs) are self-renewing, multipotent cells that could differentiate into multiple tissues. MSC-based therapy has become an attractive and promising strategy for treating human diseases through immune regulation and tissue repair. However, accumulating data have indicated that MSC-based therapeutic effects are mainly attributed to the properties of the MSC-sourced secretome, especially small extracellular vesicles (sEVs). sEVs are signaling vehicles in intercellular communication in normal or pathological conditions. sEVs contain natural contents, such as proteins, mRNA, and microRNAs, and transfer these functional contents to adjacent cells or distant cells through the circulatory system. MSC-sEVs have drawn much attention as attractive agents for treating multiple diseases. The properties of MSC-sEVs include stability in circulation, good biocompatibility, and low toxicity and immunogenicity. Moreover, emerging evidence has shown that MSC-sEVs have equal or even better treatment efficacies than MSCs in many kinds of disease. This review summarizes the current research efforts on the use of MSC-sEVs in the treatment of human diseases and the existing challenges in their application from lab to clinical practice that need to be considered.

Field evaluation of two commercial RT-rtPCR assays for porcine reproductive and respiratory syndrome virus detection using sera from ill and healthy pigs, China.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a highly contagious respiratory virus causing severe morbidity in pigs worldwide. Control strategies for PRRSV often rely on detecting PRRSV, culling or isolating sick pigs, disinfecting pig barns, vaccination, and monitoring for virus spread. Given the high economic impact of PRRSV on pig farms, there is a great need for rapid and reliable PRRSV detection assays. We compared the performance of 2 commercial reverse-transcription real-time PCR (RT-rtPCR) assays, the VetMAX PRRSV NA and EU reagents (ABI assay) and the PRRSV general RT-rtPCR kit (Anheal assay), for the molecular detection of PRRSV in sera collected from pigs in China. Between June and September 2015, sera were collected from 219 healthy and 104 suspected PRRSV-infected pigs on 4 farms in China. Employing blinding, the 2 assays were run by 2 laboratories (Guangzhou Animal Health Inspection Institute [GAHII] and Sun Yat-sen University [SYSU] laboratories) and compared. Although both assays detected PRRSV with 100% specificity at both laboratories, the sensitivity (95% vs. 78% at GAHII; 94% vs. 72% at SYSU Laboratory) and the reproducibility (kappa value 0.933 vs. 0.931) were slightly better for the ABI assay compared to the Anheal assay.

'Outbreak Gold Standard' selection to provide optimized threshold for infectious diseases early-alert based on China Infectious Disease Automated-alert and Response System.

The China Infectious Disease Automated-alert and Response System (CIDARS) was successfully implemented and became operational nationwide in 2008. The CIDARS plays an important role in and has been integrated into the routine outbreak monitoring efforts of the Center for Disease Control (CDC) at all levels in China. In the CIDARS, thresholds are determined using the "Mean+2SD? in the early stage which have limitations. This study compared the performance of optimized thresholds defined using the "Mean +2SD? method to the performance of 5 novel algorithms to select optimal "Outbreak Gold Standard (OGS)? and corresponding thresholds for outbreak detection. Data for infectious disease were organized by calendar week and year. The "Mean+2SD?, C1, C2, moving average (MA), seasonal model (SM), and cumulative sum (CUSUM) algorithms were applied. Outbreak signals for the predicted value (Px) were calculated using a percentile-based moving window. When the outbreak signals generated by an algorithm were in line with a Px generated outbreak signal for each week, this Px was then defined as the optimized threshold for that algorithm. In this study, six infectious diseases were selected and classified into TYPE A (chickenpox and mumps), TYPE B (influenza and rubella) and TYPE C [hand foot and mouth disease (HFMD) and scarlet fever]. Optimized thresholds for chickenpox (P55), mumps (P50), influenza (P40, P55, and P75), rubella (P45 and P75), HFMD (P65 and P70), and scarlet fever (P75 and P80) were identified. The C1, C2, CUSUM, SM, and MA algorithms were appropriate for TYPE A. All 6 algorithms were appropriate for TYPE B. C1 and CUSUM algorithms were appropriate for TYPE C. It is critical to incorporate more flexible algorithms as OGS into the CIDRAS and to identify the proper OGS and corresponding recommended optimized threshold by different infectious disease types.

Salidroside accelerates fracture healing through cell-autonomous and non-autonomous effects on osteoblasts.

Salidroside (SAL), a major active component of Rhodiola rosea L., exhibits diverse pharmacological effects. However, the direct roles of SAL in fracture healing remain largely unknown. Here, we demonstrate that SAL significantly promotes proliferation by altering the cell-cycle distribution of osteoblastic cells. SAL also greatly stimulates osteoblast differentiation and mineralization by inducing the expression of Runx2 and Osterix. In addition to its osteoblast-autonomous effects, SAL can activate the HIF-1α pathway coupling of angiogenesis and osteogenesis through cell-non-autonomous effects. Our in vitro results suggest that SAL significantly up-regulates HIF-1α expression at the mRNA and protein levels. Furthermore, the nuclear translocation and transcriptional activity of HIF-1α and the HIF-responsive gene VEGF increase following SAL treatment. Our mechanistic study revealed that the regulation of osteoblastic proliferation and HIF-1α expression partly involves MAPK/ERK and PI3K/Akt signaling. Our in vivo analysis also demonstrated that SAL can promote angiogenesis within the callus and accelerate fracture healing. Thus, SAL promotes skeletal regeneration in cell-autonomous and cell-non-autonomous ways and might be a potential therapy for accelerating fracture healing.

'Outbreak Gold Standard'Selection to Provide Optimized Threshold for Infectious Diseases Early-alert Based on China Infectious Disease Automated-alert and Response System / 华中科技大学学报（医学）（英德文版）

The China Infectious Disease Automated-alert and Response System (CIDARS) was successfully implemented and became operational nationwide in 2008.The CIDARS plays an important role in and has been integrated into the routine outbreak monitoring efforts of the Center for Disease Control (CDC) at all levels in China.In the CIDARS,thresholds are determined using the'Mean+2SD'in the early stage which have limitations.This study compared the performance of optimized thresholds defined using the'Mean +2SD'method to the performance of 5 novel algorithms to select optimal 'Outbreak Gold Standard (OGS)'and corresponding thresholds for outbreak detection.Data for infectious disease were organized by calendar week and year.The'Mean+2SD',C1,C2,moving average (MA),seasonal model (SM),and cumulative sum (CUSUM) algorithms were applied.Outbreak signals for the predicted value (Px) were calculated using a percentile-based moving window.When the outbreak signals generated by an algorithm were in line with a Px generated outbreak signal for each week,this Px was then defined as the optimized threshold for that algorithm.In this study,six infectious diseases were selected and classified into TYPE A (chickenpox and mumps),TYPE B (influenza and rubella) and TYPE C [hand foot and mouth disease (HFMD) and scarlet fever].Optimized thresholds for chickenpox (P55),mumps (P50),influenza (P40,P55,and P75),rubella (P45 and P75),HFMD (P65 and P70),and scarlet fever (P75 and Ps0) were identified.The C1,C2,CUSUM,SM,and MA algorithms were appropriate for TYPE A.All 6 algorithms were appropriate for TYPE B.C1 and CUSUM algorithms were appropriate for TYPE C.It is critical to incorporate more flexible algorithms as OGS into the CIDRAS and to identify the proper OGS and corresponding recommended optimized threshold by different infectious disease types.

Protective effect of salidroside against bone loss via hypoxia-inducible factor-1α pathway-induced angiogenesis.

Hypoxia-inducible factor (HIF)-1α plays a critical role in coupling angiogenesis with osteogenesis during bone development and regeneration. Salidroside (SAL) has shown anti-hypoxic effects in vitro and in vivo. However, the possible roles of SAL in the prevention of hypoxia-induced osteoporosis have remained unknown. Two osteoblast cell lines, MG-63 and ROB, were employed to evaluate the effects of SAL on cell viability, apoptosis, differentiation and mineralization in vitro. Rats subjected to ovariectomy-induced bone loss were treated with SAL in vivo. Our results showed that pre-treatment with SAL markedly attenuated the hypoxia-induced reductions in cell viability, apoptosis, differentiation and mineralization. SAL down-regulated HIF-1α expression and inhibited its translocation; however, SAL increased its transcriptional activity and, consequently, up-regulated vascular endothelial growth factor (VEGF). In vivo studies further demonstrated that SAL caused decreases in the mineral, alkaline phosphatase (ALP), and BGP concentrations in the blood of ovariectomized (OVX) rats. Moreover, SAL improved the trabecular bone microarchitecture and increased bone mineral density in the distal femur. Additionally, SAL administration partially ameliorated this hypoxia via the HIF-1α-VEGF signalling pathway. Our results indicate that SAL prevents bone loss by enhancing angiogenesis and osteogenesis and that these effects are associated with the activation of HIF-1α signalling.

The variation and clinical significance of hormone receptors and Her-2 status from primary to metastatic lesions in breast cancer patients.

The objective of this study is to investigate how the change of hormone receptor (HR) and human epidermal growth factor receptor-2 (Her-2) status is related to patients' clinical features. One hundred ninety-three cases of patients treated at general hospital of PLA from 2000 to 2015 with advanced breast cancer were included. All patients developed recurrence that were re-biopsied and had complete pathological profile both at initial diagnosis and at relapse. HR status before and after relapse were available for all patients, while only 143 cases had Her-2 status at the two stages. The changes of ER, PR, and Her-2 status and their association with clincopathological factors and DFS were analyzed. The discordant rates of ER, PR, and Her-2 status between primary breast cancer and recurrent tumor were 34.2, 38.3, and 16.8 %, respectively. At relapse, the rates of gain of ER and PR positivity were 10.9 and 13.5 %, respectively; the rates of loss of ER and PR positivity were 23.3 and 24.9 %. Loss of positivity was more frequent than gain of positivity (p ER < 0.000, p PR = 0.001). Among patients with Her-2 negative primary tumors, 15.4 % acquired Her-2 positivity at relapse; and among Her-2 positive patients at initial diagnosis, 1.4 % turned to Her-2 negative at relapse; gain of positivity was more frequent than loss of positivity (p < 0.000). Patients with tumor larger than 2 cm in diameter were more likely to experience change of Her-2 status (25.0 vs 5.8 %, p = 0.005). Yet, the change of ER/PR was not significantly associated with the size of primary tumor. Patients with ER positive recurrent disease and PR positive primary tumor had a DFS of more than 40 months. Compared to patients who maintained PR negative, patients who gained PR positivity at relapse had significantly longer DFS by 8.5 % (35.2 vs 26.7 months, p = 0.024). Patients losing ER positivity at relapse had shorter DFS by 7.8 months compared to those with stable ER positive tumors; patients gaining ER positivity experienced longer DFS by 8.3 months; but both differences were not statistically significant. Loss of Her-2 positivity was associated with longer DFS by 13.8 months as opposed to stable Her-2 status, without statistical significance. For patients with Her-2 negative primary tumor, the changes of Her-2 status were not associated with DFS. 34.2, 38.3, and 16.8 % of breast cancer patients had their ER, PR, and Her-2 status changed after recurrence, and these changes of receptor status were associated with DFS to some degree. Gain of PR positivity at relapse was significantly correlated with longer DFS.

IL6 induces TAM resistance via kinase-specific phosphorylation of ERα in OVCA cells.

About 40-60% of ovarian cancer (OVCA) cases express ERα, but only a small proportion of patients respond clinically to anti-estrogen treatment with estrogen receptor (ER) antagonist tamoxifen (TAM). The mechanism of TAM resistance in the course of OVCA progression remains unclear. However, IL6 plays a critical role in the development and progression of OVCA. Our recent results indicated that IL6 secreted by OVCA cells may promote the resistance of these cells to TAM via ER isoforms and steroid hormone receptor coactivator-1. Here we demonstrate that both exogenous (a relatively short period of treatment with recombinant IL6) and endogenous IL6 (generated as a result of transfection with a plasmid encoding sense IL6) increases expression of pERα-Ser118 and pERα-Ser167 in non-IL6-expressing A2780 cells, while deleting endogenous IL6 expression in IL6-overexpressing CAOV-3 cells (by transfection with a plasmid encoding antisense IL6) reduces expression of pERα-Ser118 and pERα-Ser167, indicating that IL6-induced TAM resistance may also be associated with increased expression of pERα-Ser118 and pERα-Ser167 in OVCA cells. Results of further investigation indicate that IL6 phosphorylates ERα at Ser118 and Ser167 by triggering activation of MEK/ERK and phosphotidylinositol 3 kinase/Akt signaling, respectively, to activate the ER pathway and thereby induce OVCA cells resistance to TAM. These results indicate that IL6 secreted by OVCA cells may also contribute to the refractoriness of these cells to TAM via the crosstalk between ER and IL6-mediated intracellular signal transduction cascades. Overexpression of IL6 not only plays an important role in OVCA progression but also promotes TAM resistance. Our results indicate that TAM-IL6-targeted adjunctive therapy may lead to a more effective intervention than TAM alone.

Approaches to the evaluation of malaria elimination at county level: case study in the Yangtze River Delta region.

As the progress on transition from malaria control to malaria elimination in the People's Republic of China (P.R. China), four counties/districts, namely Zhabei District and Songjiang District of Shanghai municipality, and Anji County and Haiyan County of Zhejiang Province, representatives of the Yangtze River Delta region, were included in the pilot project of the national malaria elimination programme in P.R. China. A baseline survey was conducted first. The main measures performed were blood examination of febrile cases, improving the information management system of malaria cases, providing standard diagnosis and treatment, standardized disposal of epidemic focus, and health education and health promotion, strengthening the management of mobile population, etc. All the measures were assessed and evaluated through data examination and on-site investigation. In the whole process of the pilot project, quality control was especially emphasized. During the implementation of pilot project, the three-level control system was improved, professional staff was enriched and the working fund was ensured (a total fund of RMB 2,923,600). Thirty-nine training courses were conducted. Among 102,451 febrile cases receiving blood examination, all of the 23 malaria cases were confirmed as imported from other provinces or foreign countries. All the epidemic foci were surveyed and some control measures were carried out. Various health education and promotion activities were carried out including publicizing malaria control knowledge through news media, newspapers and periodicals and networks. Assessment and evaluation of the project was done by the Zhejiang and Shanghai Government, comprehensive score was >95 points under the evaluation system which indicated all four pilot counties/districts had first achieved the goal of elimination of malaria in P.R. China. Experiences and lessons about the measures carried out in the project were discussed.

Unusual mucoepidermoid carcinoma of the liver misdiagnosed as squamous cell carcinoma by intraoperative histological examination.

As rare condition, mucoepidermoid carcinoma may occur in liver although its etiology and pathogenesis is still unclear. We report here a case of intrahepatic mucoepidermoid carcinoma misdiagnosed as cholangiocarcinoma and squamous cell carcinoma by preoperative radiologic and intraoperative histological examinations, respectively. A 60-year-old woman presented with a 1-month history of progressive jaundice, epigastric discomfort, and weight loss with slightly increased carbohydrate antigen 19-9 (CA19-9). Computed tomography (CT) showed a large tumor, 8.0 cm in diameter, in the left lobe of the liver. A preliminary diagnosis of a cholangiocarcinoma of the liver was made. In the intraoperative histological examination, a diagnosis of squamous cell carcinoma was made based on predominantly invasive epidermoid cells with abundant keratinization and absence of mucin-producing cell component. However, postoperative histological diagnosis of the lesion was mucoepidermiod carcinoma of liver by thoroughly microscopical inspection and the presence of mucin-producing cells confirmed by Alcian blue staining. Despite surgical excision and chemotherapy, the tumor showed very aggressive malignancy with tumor recurrence. The patient died shortly afterward, surviving 6 months after surgery. Due to its rarity and distinct morphological features, mucoepidermoid carcinoma might be erroneously interpreted as squamous cell carcinoma by those who were not familiar with this condition in unusual locations. Therefore, removal of sufficient tissue from different portions of the lesion is essential for the surgeons and pathologists to make a precise diagnosis in the intraoperative histological examination. VIRTUAL SLIDE: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4956311271136060.

[Effects of exogenous melatonin on active oxygen metabolism of cucumber seedlings under high temperature stress].

Taking the seedlings of cucumber cultivar 'Jinchun 4' as test material, this paper studied the effects of foliar application of exogenous melatonin (MT) on the active oxygen metabolism of the seedlings under high temperature stress. Under the stress, the exogenous MT could significantly decrease the leaf superoxide radical (O2-*) production rate, hydrogen peroxide (H2O2) content, cell membrane permeability (electrolyte leakage), and malonaldehyde (MDA) content, but increase the activities of superoxide radical (SOD), peroxidase (POD), and catalase (CAT), and the contents of ascorbic acid (AsA), glutathione (GSH), and soluble proteins, illustrating that pretreatment with MT could inhibit the reactive oxygen species (ROS) production, raise the antioxidative enzyme activities and antioxidant contents, and decrease the membrane lipid peroxidation and electrolyte leakage to protect the integrity of lipid membranes, being able to alleviate the damage of high temperature stress to the seedlings.

[Relationship of IL-6 and IL-8 secretion in epithelial ovarian cancer cell lines with their sensitivity to tamoxifen as well as MAPK, Akt and estrogen receptor phosphorylation].

AIM: To investigate the relationship of IL-6 and IL-8 secretion in four epithelial ovarian cancer cell lines (A2780, CAOV-3, SKOV-3 and ES-2) with their sensitivity to tamoxifen (TAM) as well as MAPK, Akt and estrogen receptor (ER) phosphorylation, and to explore the mechanism of endocrine therapy resistance caused by IL-6 and IL-8 in ovarian cancer cells. METHODS: Reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA) were performed to analyze the expression of IL-6 and IL-8. MTT assay was carried out to examine the response of ovarian cancer cells to TAM. Western blot was used to detect phosphorylated MAPK, Akt and ER. RESULTS: Except A2780 cells, three other ovarian cancer cells constitutively expressed IL-6 and IL-8. The mRNA levels of IL-6 and IL-8 correlated with their protein levels in four ovarian cancer cells. The four ovarian cancer cells showed different response to TAM. A2780 cells was the most responsive, whereas CAOV-3, SKOV-3 and ES-2 cells were TAM-resistant to a different degree. There was a notable difference in phosphorylated MAPK, Akt and ER (serine 118 and 167) among the four ovarian cancer cells. CONCLUSION: Autocrine production of IL-6 and IL-8 in epithelial ovarian cancer cell lines is inversely associated with cell response to TAM, and positively associated with phosphorylated MAPK, Akt and ER.

[Effects of climate warming and drying on millet yield in Gansu Province and related countermeasures].

Based on the data of air temperature, precipitation, and millet yield from Ganzhou, Anding, and Xifeng, the representative stations in Hexi moderate arid oasis irrigation area, moderate sub-arid dry area in middle Gansu, and moderate sub-humid dry area in eastern Gansu, respectively, this paper calculated the regional active accumulated temperature of > or = 0 degrees C, > or =5 degrees C, > or =10 degrees C, > or =15 degrees C, and > or =20 degrees C in millet growth period, and the average temperature and precipitation in millet key growth stages. The millet climatic yield was isolated by orthogonal polynomial, and the change characteristics of climate and millet climatic yield as well as the effects of climate change on millet yield were analyzed by statistical methods of linear tendency, cumulative anomaly, and Mann-Kendall. The results showed that warming and drying were the main regional features in the modern climatic change of Gansu. The regional temperature had a significant upward trend since the early 1990s, while the precipitation was significantly reduced from the late 1980s. There were significant correlations between millet yield and climatic factors. The millet yield in dry areas increased with the increasing temperature and precipitation in millet key growth stages, and that in Hexi Corridor area increased with increasing temperature. Warming and drying affected millet yield prominently. The weather fluctuation index of regional millet yield in Xifeng, Anding, and Ganzhou accounted for 73%, 72%, and 54% of real output coefficient variation, respectively, and the percentages increased significantly after warming. Warming was conducive to the increase of millet production, and the annual increment of millet climatic yield in Xifeng, Anding, and Ganzhou after warming was 30.6, 43.1, and 121.1 kg x hm(-2), respectively. Aiming at the warming and drying trend in Gansu Province in the future, the millet planting area in the Province should be further expanded, and the millet planting structure should be adjusted. At the same time, according to the different regional and yearly climatic types, different varieties should be selected, and various planting measures should be taken.

[Effects of exogenous melatonin on ascorbate metabolism system in cucumber seedlings under high temperature stress].

Taking cucumber cultivar 'Jinchun 4' as test material, and by the method of foliar spraying, this paper studied the effects of exogenous melatonin (MT) on the ascorbic acid (AsA) metabolism system in cucumber seedlings under high temperature stress. Under the stress of high temperature, the leaf hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents of the cucumber seedlings increased obviously, ascorbic acid (AsA) and glutathione (GSH) contents had a persistent decrease while dehydroascorbate (DHA) and oxidized-glutathione (GSSG) contents had a gradual increase, and AsA/DHA and GSH/GSSG decreased greatly. The activities of ascorbate peroxidase (APx), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) in the seedling leaves under high temperature stress increased markedly, with the maximum after 12 h stress. Foliar spraying MT could effectively restrain the accumulation of H2O2 and MDA in seedling leaves, increase the leaf AsA and GSH contents and the activities of ascorbic acid metabolizing enzymes APx, MDHAR, GR and DHAR, and accordingly, enhance the H2O2-scavenging ability, inhibit the production of active O2, maintain the stability of cell membrane, reduce the damage of high temperature to the plants, and improve the ability of cucumber seedlings against high temperature stress.

[Construction and expression of human IL-8 sense or antisense eukaryotic expression vectors].

AIM: To construct the sense or antisense IL-8 eukaryotic expression vectors. METHODS: Sense or antisense IL-8 full length gene were amplified by RT-PCR and cloned into eukaryotic expression vector pcDNA3.1(+). After the identification by PCR, restriction endonuclease digestion and the nucleotide sequencing, the recombinant vectors were transfected into human ovarian carcinoma A2780 and SKOV3 cell lines transiently by lipofectamine mediation. The expression of IL-8 gene and protein were detected by RT-PCR and ELISA. RESULTS: The sense or antisense IL-8 eukaryotic expression vectors were constructed and verified. The expression of IL-8 gene and protein in A2780 cells transfected with pcDNA3.1(+)-ssIL-8 were increased, whereas the expression of IL-8 protein in SKOV3 cells transfected with pcDNA3.1(+)-asIL-8 was decreased. CONCLUSION: The eukaryotic expression vectors pcDNA3.1(+)-ssIL-8 or pcDNA3.1(+)-asIL-8 have been constructed successfully, which lays a base for further study on roles of IL-8 in ovarian cancer and other tumors.