Exploring barriers to dementia screening and management services by general practitioners in China: a qualitative study using the COM-B model.

BACKGROUND: Dementia has become a global public health problem, and general practitioners (GPs) play a key role in diagnosing and managing dementia. However, in Chinese primary care settings, dementia is underdiagnosed and inefficiently managed, and dementia screening and management services provided by GPs are suboptimal. The reasons underlying this gap are poorly understood. This study aimed to determine the barriers that hinder GPs from actively promoting dementia screening and management, and thereby provide insights for the successful promotion of dementia screening and management services in primary care. METHODS: Purposive sampling was used. And focus groups and in-depth interviews were conducted face-to-face among GPs from community health service centers (CHSCs) in South China. Thematic analysis was used to identify barriers to screening and managing dementia and map them to the Capability/Opportunity/Motivation-Behavior model (COM-B model). RESULTS: Fifty-two GPs were included. The COM-B model found nine barriers to implementing dementia screening and management services in primary healthcare: (1) poor capability: lack of systematic knowledge of dementia and inadequate dementia screening skills; (2) little opportunity: unclear pathways for referral, insufficient time for dementia screening and management, lack of dementia-specific leaders, and no guarantee of services continuity; (3) low motivation: outside of GP scope, worries associated with dementia stigma rooted in culture beliefs, and insufficient financial incentives. CONCLUSIONS: Our study concluded that GPs were not yet ready to provide dementia screening and management services due to poor capability related to knowledge and skills of dementia, little opportunity associated with an unsupportive working environment, and low motivation due to unclear duty and social pressure. Accordingly, systematic implementation strategies should be taken, including standardized dementia training programs, standardized community-based dementia guidelines, expansion of primary care workforces, development of dedicated leaders, and the eradication of stigma attached to dementia to promote dementia screening and management services in primary care.

A home-made sampling system coupled to hectowatt-MPT mass spectrometry in positive ion mode to confirm target ions of copper and zinc from Poyang Lake, China.

A novel home-made H2SO4-Nafion (HN) tube sampling system coupled to a line ion trap mass spectrometer (LTQ-MS) with a versatile ambient ionization source, hectowatt microwave plasma torch (HMPT), has manifested unique advantages for picking directly metal elements in aqueous samples and acquiring the fully characteristic MPT mass spectra of copper and zinc composite ions. Here, we report the development of a novel HN-HMPT-LTQ-MS for metal elements assay based on environmental water to analyze samples of Poyang Lake, China. Detailed multi-stage tandem mass spectra show that the general structural form of target ions is [M(NO3)x(H2O)y(OH)z]+ for the positive ion mode. Under the optimized conditions, the proposed method provided low limits of detection (LODs) of 0.23 µg.L-1 for 63Cu+ and 1.1 µg.L-1 for 66Zn+, with relative standard deviations (RSDs) of less than 12.7% by MPT-LTQ-MS. This new result has met the requirements of national standards (GB 5750.6-2006) and is only about one magnitude order larger than the LOD of ICP-MS method. A wide linear response range of about 4 orders of magnitude for the method with linear coefficients (R2) of 0.99709 - 0.99962 for copper and zinc tested was in accordance with that of ICP-MS. Except for the recovery of 79% for the third sample and 123.8% for the seventh sample, the present method also provided good recoveries (84 - 119.3%) in spiked 10 batches of drinking water samples. Furthermore, it is envisioned that the developed approach might build a powerful hectowatt-MPT-MS platform for food security detection, drug analysis, and origin traceability.

Comparison of Intra-Abdominal Pressure Measurements in Critically Ill Patients Using Intravesical Normal Saline at 15°C, 25°C, and 35°C.

BACKGROUND The incidence of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) in intensive care units is high. Dynamic monitoring of intra-abdominal pressure (IAP) is important to treat patients with these conditions. The World Society of Abdominal Compartment Syndrome revised IAP measurement and treatment guidelines in 2013. IAP is measured by instilling ≤25 mL of sterile saline into the bladder, but there is no requirement for the saline to be at a specific temperature. Many doctors presume that using cold saline will trigger bladder muscle spasms, resulting in measurement error. In the present study, we investigated the effect of body-temperature saline on IAP measurements. MATERIAL AND METHODS A single-center study was conducted in 12 patients with IAH over a 2-year period. IAP was measured via the bladder with instillation of sterile saline at temperatures of 35°C, 25°C, and 15°C. We analyzed the data using R software, version 4.1.0. Paired t tests were used for comparisons between groups. A Spearman rank correlation analysis was performed to compare groups. Analysis results were plotted using the R packages ggplot2, ggpubr, and BlandAltmanLeh. P<0.05 was considered statistically significant. RESULTS There was a significant difference in IAP measurement between the 15°C and 35°C groups (t=-2.55, P=0.027). There was no significant difference between the 25°C and 35°C groups (t=0.73, P=0.48). Bland-Altman analysis showed that IAP was consistent in the 25°C and 35°C groups. CONCLUSIONS Although it is preferable to measure IAP with saline at body temperature (35°C), a temperature >25°C is associated with accurate results. Using saline at <15°C should be avoided.

[Clinical application of enteral immune nutrition for chronic obstructive pulmonary disease patients].

OBJECTIVE: To explore the application of enteral immune nutrition preparation for chronic obstructive pulmonary disease (COPD) patients and examine the improving effects on nutritional status, immune status and acute inflammatory reaction. METHODS: A total of 60 cases of hospitalized COPD patients on mechanical ventilation in intensive care unit (ICU) were randomly divided into immune nutrition group (containing essential fatty acids, omega-3 fatty acids, energy 1.3 kcal/ml) (study, n = 30) and standard nutrition group (self-made homogenized diet 1.2 kal/ml) (control, n = 30). Two groups received an equal calorie of enteral nutrition via a nasointestinal tube. On the day of admission and every 2 weeks, venous blood samples were drawn for measuring the serum levels of albumin (ALB), prealbumin (PA), C-reactive protein (CRP) and interleukin-6 (IL-6). And the values of upper arm muscle circumference (MAMC) were recorded simultaneously bedside. The levels of mechanical ventilation and weaning rate were compared between two groups at Day 14. RESULTS: The weaning rate within 14 days in study group was higher than that in control group (73.3% vs 43.3%, P < 0.05). And PA at Day 14 in study group was higher than that in control group [(188.4 ± 57.5) vs (174.6 ± 65.7) mg/L, P < 0.05], ALB at Day 14 also higher than control group [(32.7 ± 4.6) vs (30.2 ± 3.8) g/L, P < 0.05], MAMC at Day 28 better than control group [(25.5 ± 2.1) cm vs (24.3 ± 1.8) cm, P < 0.05]. No significant inter-group difference in IL-6 existed at Day 14 [(250.1 ± 110.3) vs (266.1 ± 97.3) ng/L, P > 0.05]. The study group was lower than control group at Day 28 [(108.5 ± 59.6) vs (165.7 ± 76.3) ng/L, P < 0.05]. The CRP levels at Day 14 [(12.2 ± 7.3) vs (13.2 ± 6.9) mg/L, P < 0.05] and at Day 28 [(7.5 ± 5.0) vs (9.6 ± 5.6) mg/L, P < 0.05] were lower than those of control group at Days 14 and 28. CONCLUSION: Compared with homogenized diet, immune enteral nutrition may improve the nutritional status of COPD patients, lower the levels of acute inflammatory reactions and boost the success rate of early weaning.

Precise Marketing of E-Commerce Products Based on KNN Algorithm.

In order to better understand the purchase decision-making process of consumers, this paper makes an in-depth study on the precision marketing of e-commerce products on the basis of KNN algorithm. Through data mining, classic KNN algorithm, BPNN algorithm, and other methods, this paper takes the price and purchase intention of e-commerce agricultural products as an example. Based on the classic nearest neighbor algorithm, binomial function is combined with Euclidean distance formula when calculating the nearest neighbor through similarity. The particle swarm optimization algorithm is used to optimize the binomial function coefficient and the K value of the nearest neighbor algorithm, and the results of the best prediction model for the prediction application of e-commerce agricultural product price and purchase intention are established. Both pricing strategies and promotion strategies will weaken the compromise effect of consumers when they choose e-commerce agricultural products. After studying the calculation method of the KNN algorithm, it not only correctly predicts the price of e-commerce agricultural products but also makes a corresponding prediction and analysis of consumers' purchase intention of e-commerce agricultural products, with the highest accuracy of 94.2%. At the same time, in the future precision marketing process, e-commerce agricultural products enterprises use data technology to achieve precision marketing, which effectively changes the shortcomings of traditional marketing and improves the product marketing effect and economic benefits.

Insight into derivative Weibull mixture model in describing simulated distributed activation energy model and distillers dried grains with solubles pyrolysis processes.

The kinetics of biomass pyrolysis is fundamental for exploring its mechanisms and optimizing its processes, which is helpful for designing its systems. The derivative Weibull mixture model was proposed for kinetic description of the simulated distribution energy model (DAEM) processes and distillers dried grains with solubles (DDGS) pyrolysis processes. The conversion rate data of these processes at different heating rates could be accurately described by the derivative Weibull mixture model. Moreover, the proposed model could effectively smooth the noises contained in the experimental conversion rate data of DDGS pyrolysis. The derivative Weibull mixture model separated DDGS pyrolysis reactions into several individual processes, and provided some data required for further isoconversional kinetic analysis. The predicted curves from the derivative Weibull mixture model allowed us to obtain the effective activation energies of DDGS pyrolysis, which varied significantly from 170 to 330 kJ mol-1 in the conversion range between 0.1 and 0.9.

Platelet factor-4 and its p17-70 peptide inhibit myeloma proliferation and angiogenesis in vivo.

BACKGROUND: Angiogenesis plays an important role in the development of multiple myeloma (MM). The interaction between MM cells and the bone marrow microenvironment stimulates the proliferation and migration of endothelial progenitor cells (EPCs). Vascular endothelial growth factor (VEGF) contributes to the formation of new blood vessels by actively recruiting circulating EPCs. The production of proangiogenic and antiangiogenic factors is also dysregulated in MM. Platelet factor 4 (PF4) is a potent angiostatic cytokine that inhibits angiogenesis and tumor growth in several animal models. METHODS: In this study, we stably transfected human myeloma cell lines with the PF4 gene or the sequence encoding its more potent p17-70 peptide and investigated the effects of PF4 and p17-70 on angiogenesis and tumor growth in vitro and in a SCID-rab myeloma model. RESULTS: PF4 and p17-70 significantly attenuated VEGF production, both in vitro and in vivo. In a migration study using a Transwell system, PF4 or p17-70 markedly suppressed the migration of co-cultured human endothelial progenitor cells. PF4 or p17-70 also caused a significant reduction in microvessel densities in myeloma xenografts and markedly reduced the tumor volume in the SCID mice. Kaplan-Meier analysis demonstrated that PF4 and p17-70 significantly extended the overall survival of SCID mice bearing human myeloma xenografts. CONCLUSIONS: Our findings indicate that PF4 or p17-70 could be valuable in combating multiple myeloma by disrupting tumor angiogenesis.

Synthesis of quinolin-2-one alkaloid derivatives and their inhibitory activities against HIV-1 reverse transcriptase.

Based on an established common pharmacophore of HIV-1 non-nucleoside reverse transcriptase inhibitors (NNTTIs), a series of quinolin-2-one derivatives were synthesized and assayed for their in vitro activities against HIV-1 reverse transcriptase (RT) for the first time. Some of the tested compounds were active against HIV-1 RT. Compounds 4a2 and 4d2 showed inhibitory activities with IC(50) values of 0.21 and 0.15 mM, respectively, with a mode of interaction with RT residues of the allosteric pocket similar to that of efavirenz.

Differential expression of DKK-1 binding receptors on stromal cells and myeloma cells results in their distinct response to secreted DKK-1 in myeloma.

BACKGROUND: The canonical Wnt signaling is concurrently important for osteoblast differentiation and myeloma cell proliferation. Its activation in myeloma cells and its inhibition in osteoblasts and their progenitors have been identified in the previous studies. Osteoblast progenitors and myeloma cells from a myeloma patient share the same bone marrow (BM) microenvironment, but respond differently to DKK-1 secreted by myeloma cells. The mechanisms remain unclear. METHODS: Primary multiple myeloma (MM) cells were isolated from BM mononuclear cells of 12 MM patients. Human bone marrow stromal cells (SCs) were obtained from BM adherent cells of these MM patients and 10 healthy donors. The mRNA expression levels of DKK-1 binding receptor LRP5/6 and Kremen1/2 (Krm1/2) were analyzed by Real-time PCR in human myeloma cell line (HMCL) RPMI-8226, NCI-H929, U266, LP-1, CZ-1, KM-3, Sko-007, primary myeloma cells and SCs from 12 MM patients and SCs from 10 healthy donors. The binding capability of DKK-1 binding receptors to DKK-1 on primary myeloma cells and SCs was detected by flow cytometry assay. RESULTS: The mRNA expression levels of DKK-1 binding receptor LRP5/6 and Krm1/2 in SCs from patients with MM were significantly higher than those in myeloma cells and in SCs from healthy donors. The binding capability to DKK-1of DKK-1 binding receptors on SCs from MM patients was obviously higher than those on myeloma cells and SCs from healthy donors by flow cytometry assay. Similar to the effects of coculture with rhDKK1, coculture of SCs from healthy donors with myeloma cells in the presence or absence of a Transwell insert did up-regulate SCs' mRNA levels of LRP5/6 and Krm1/2, and down-regulate their mRNA levels of ß-catenin. CONCLUSION: Compared with myeloma cells, the SCs from MM patients overexpress DKK-1 binding receptors LRP5/6 and Krm1/2 in response to DKK-1 secreted by myeloma cells, which results in intracellular Wnt signaling inhibition. Our study provides a novel insight into mechanisms of myeloma associated osteolytic lesions.

Characterization of Starch in Cucurbita moschata Germplasms throughout Fruit Development.

Pumpkins (Cucurbita moschata; Cucurbitaceae) are the rich source of nutrients and valued for their biologically active substances to be used for the treatment of several diseases. The contents, composition, and conformation of starch are the significant quality traits of C. moschata. Two germplasms were targeted for analysis regarding the taste difference. Results indicated that the total starch contents and amylose/amylopectin ratio were high in CMO-X as compared to CMO-E during each fruit development stage. Scanning electron microscopy and transmission electron microscopy observations revealed that smooth surface starch granules fused together to enhance the starch accumulation. For a comparison of fruit development in CMO-E and CMO-X, the putative pathway for starch metabolism was developed and homologs were identified for each key gene involved in the pathway. GBSS and SBE were correlated with the difference in the amylose/amylopectin ratio of CMO-E and CMO-X. Conclusively, the developmental regulation of genes associated with starch accumulation can be considered as an important factor for the determination of fruit quality.

[Establishment of a bortezomib-resistant myeloma cell line and differential proteins analysis by MALDI-OF-MS].

OBJECTIVE: To establish a bortezomib-resistant myeloma cell line and to investigate its mechanism. METHODS: Bortezomib-resistant NCI-H929 cell line (NCI-H929B) was obtained by stepwise increasing extracellular concentrations of bortezomib over a period of 8 months. The biological characteristics of NCI-H929 and NCI-H929B were observed. Proteins from NCI-H929B cell and NCI-H929 cell were extracted, run on two-dimensional gel electrophoresis. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and mass spectrometry (MS) were used to identify proteins. Western blot was used to further verify differential proteins. RESULT: Bortezomib-resistant cell line NCI-H929B was established. NCI-H929B exhibits a 23.5-fold level of resistance to bortezomib as compared to the parental cell line NCI-H929. There were no significant differences in cellular biology of cell growth curve and cell cycle distribution between NCI-H929 and NCI-H929B cell lines.Whole proteins of NCI-H929 and NCI-H929B myeloma cell lines were extracted by two-dimensional gel electrophoresis. Gel-image analysis revealed that there were 17 differential protein spots. A total of 14 differential protein spots were successfully identified by MALDI-TOF-MS. The result of Western blot was consistent with 2-DE. CONCLUSION: A bortezomib-resistant human myeloma cell line NCI-H929B was successfully established. The differentially expression of proteomes may be useful for study of the bortezomib-resistant mechanisms and the molecular markers of MM.

MicroRNA-138 attenuates myocardial ischemia reperfusion injury through inhibiting mitochondria-mediated apoptosis by targeting HIF1-α.

Myocardial ischemia-reperfusion (I/R) injury is considered to have a detrimental role in coronary heart disease, which is considered to be the leading cause of death worldwide. However, the molecular mechanism involved in the progression of myocardial I/R injury is still unclear. The current study aimed to investigate the expression and function of microRNA (miR)-138 in the process of myocardial I/R injury. First, miR-138 expression levels were analyzed both in myocardium with I/R injury and control myocardium using reverse transcription-quantitative polymerase chain reaction analysis. Then, the relationship between the levels of miR-138 and hypoxia-inducible factor (HIF)1-α was also investigated using a luciferase reporter assay. Assessment of myocardial infarct size, measurements of serum myocardial enzymes and electron microscopy analysis were all utilized to analyse the effect of miR-138 on myocardial I/R injury. The authors of current study also used western blotting to examine the expression levels of the mitochondrial fission-related proteins dynamin-1-like protein and mitochondrial fission 1 protein. It was found that miR-138 is downregulated and HIF1-α is upregulated after myocardial ischemia reperfusion injury. Overexpression of miR-138 reduced myocardial I/R injury-induced infarct sizes and myocardial enzyme levels, and it also inhibited the expression of proteins related to mitochondrial morphology and myocardial I/R-induced mitochondrial apoptosis by targeting HIF1-α. Taken together, these findings provide a novel insight into the molecular mechanism of miR-138 and HIF1-α in the progression of myocardial I/R injury. miR-138 has the potential to become a promising therapeutic target for treating myocardial I/R injury.

Diabetes in Shenzhen, China: epidemiological investigation and health care challenges.

BACKGROUND: Understanding epidemiological characteristics of diabetes in a specific population will potentially benefit prevention and control of diabetes and policy-making. This study aimed to investigate the prevalence and awareness of diabetes, as well as its pharmacological, non-pharmacological and primary care management in Shenzhen, China. METHODS: A cross-sectional study was conducted. We employed multistage cluster random sampling methods to select the participants. Face-to-face interview surveys were conducted to collect data. A total of 1676 participants completed the survey. RESULTS: We found that the prevalence of diabetes was 4.8%. The prevalence of impaired fasting blood glucose was 6.0%. The prevalence rates of both diabetes and impaired fasting blood glucose increased with age (P < 0.001), whereas hypertension was strongly associated with diabetes only (odds ratio (OR) = 1.93, 95% confidence interval (CI) 1.15-3.22). The awareness of diabetes was poor (51.9%) and 54.3% of diabetic patients were not being treated pharmacologically. Less than one-third of diabetic patients were undergoing non-pharmacological treatments. Primary care management of diabetes was recorded for only 11.1% of the patients. CONCLUSIONS: Although diabetes prevalence in Shenzhen is about a half that of the Chinese average, high prevalence of impaired fasting blood glucose imposes a public health threat and burden to the health care system. Approximately half of the subjects with diabetes are undiagnosed. Our findings highlight the need of public health efforts for primary and secondary prevention, as well as early detection of diabetes. Primary care may be crucial an improved access to medical services and better management of diabetes.

A cross-sectional study of the prevalence, awareness, treatment and control of hypertension in Shenzhen, China.

OBJECTIVES: An understanding of the awareness, treatment and control of hypertension is helpful to guide decision-making regarding interventions to reduce the risk for diseases with hypertension as a key risk factor. This study aimed to estimate the prevalence, awareness, treatment, and control of hypertension in Shenzhen, China. METHODS: A cross-sectional study was conducted. We employed multistage cluster random sampling methods to select participants. A survey involving face-to-face interviews was conducted to collect the data. A total of 1676 participants finished the survey and formed the final analysis. RESULTS: We found that the prevalence of hypertension was 17.6%. The rates of hypertension awareness, treatment and control were 48.8%, 51.4% and 43.2% respectively. Only 6.8% hypertensives were found to be managed by community health centres. Compared with the female participants, the males were found to have higher rates of prevalence (19.7% vs 15.7%; OR 1.47, 95% CI 1.10 to 1.97) and awareness (42.9% vs 38.1%; OR 2.35, 95% CI 1.28 to 4.33), but lower rates of medication treatments (20.5% vs 30.2%; OR 0.83, 95% CI 0.05 to 0.92) and control (12.8% vs 23.0%; OR 0.45, 95% CI 0.21 to 0.96). Migrants were more likely to be aware of hypertension (32.5% vs 44.3%; OR 0.57, 95% CI 0.30 to 0.90), reduce their salt intake (8.8% vs 18.1%; OR 0.40, 95% CI 0.15 to 0.94), and undertake regular monitoring of hypertension (1.3% vs 11.0%; OR 0.14, 95% CI 0.02 to 0.92) when compared with the locals. CONCLUSIONS: Our study finds that hypertension is an important public health burden in Shenzhen. It implies that strategies need to be developed to improve effective primary care management of hypertension. It also suggests a need to develop gender and household register tailored strategies for the prevention, detection, treatment and control of hypertension.

Unfolded protein response inducers tunicamycin and dithiothreitol promote myeloma cell differentiation mediated by XBP-1.

The unfolded protein response (UPR) is an essential pathway for both normal and malignant plasma cells to maintain endoplasmic reticulum (ER) homeostasis in response to the large amount of immunoglobulin (Ig) output. The inositol-requiring enzyme 1-X-box binding protein-1 (IRE1-XBP-1) arm of the UPR pathway has been shown to play crucial roles not only in relieving the ER stress by up-regulating a series of genes favoring ER-associated protein degradation and protein folding, but in mediating terminal plasmacytic differentiation and maturation. Myeloma cells comprise various subsets arrested in diverse differentiated phases, and the immaturity of myeloma cells has been taken as a marker for poor prognosis, suggesting that differentiation induction would be a promising therapeutic strategy for myeloma. Herein, we used low-dose pharmacological UPR inducers such as tunicamycin (TM) and dithiothreitol (DTT) to efficiently activate the IRE1-XBP-1 pathway in myeloma cells characterized by transcriptional expression increase in spliced XBP-1 and molecular chaperons, accompanied by significant differentiation and maturation of these myeloma cells, without concomitant cytotoxicity. These differentiated myeloma cells exhibited a more mature appearance with well-developed cytoplasm and a reduced nucleocytoplasmic ratio, and a further differentiated phenotype with markedly increased expression of CD49e together with significantly elevated cellular secretion of Ig light chain as shown by flow cytometry and ELISA, in contrast to the control myeloma cells without exposed to TM or DTT. Moreover, siRNA knockdown of XBP-1 disrupted TM- or DTT-induced myeloma cell differentiation and maturation. Our study, for the first time, validated that the modest activation of the UPR pathway enables myeloma cells to further differentiate, and identified that XBP-1 plays an indispensable role in UPR-mediated myeloma cell differentiation and maturation. Thus, we provided the rationale and feasibility for the exploration of the novel therapeutic strategy of differentiation induction for plasmacytic malignancies.

Arsenic trioxide exerts antimyeloma effects by inhibiting activity in the cytoplasmic substrates of histone deacetylase 6.

Arsenic trioxide (As(2)O(3)) has shown remarkable efficacy for the treatment of multiple myeloma (MM). Histone deacetylases (HDAC) play an important role in the control of gene expression, and their dysregulation has been linked to myeloma. Especially, HDAC6, a unique cytoplasmic member of class II, which mainly functions as α-tubulin deacetylase and Hsp90 deacetylase, has become a target for drug development to treat cancer due to its major contribution in oncogenic cell transformation. However, the mechanisms of action for As(2)O(3) have not yet been defined. In this study, we investigated the effect of As(2)O(3) on proliferation and apoptosis in human myeloma cell line and primary myeloma cells, and then we studied that As(2)O(3) exerts antimyeloma effects by inhibiting activity in the α-tubulin and Hsp90 through western blot analysis and immunoprecipitation. We found that As(2)O(3) acts directly on MM cells at relatively low concentrations of 0.5~2.5 µM, which effects survival and apoptosis of MM cells. However, As(2)O(3) inhibited HDAC activity at the relatively high concentration and dose-dependent manner (great than 4 µM). Subsequently, we found that As(2)O(3) treatment in a dose- and time-dependent fashion markedly increased the level of acetylated α-tubulin and acetylated Hsp90, and inhibited the chaperone association with IKKα activities and increased degradation of IKKα. Importantly, the loss of IKKα-associated Hsp90 occurred prior to any detectable loss in the levels of IKKα, indicating a novel pathway by which As(2)O(3) down-regulates HDAC6 to destabilize IKKα protein via Hsp90 chaperone function. Furthermore, we observed the effect of As(2)O(3) on TNF-α-induced NF-κB signaling pathway was to significantly reduced phosphorylation of Ser-536 on NF-κB p65. Therefore, our studies provide an important insight into the molecular mechanism of anti-myeloma activity of As(2)O(3) in HDAC6-Hsp90-IKKα-NFκB signaling axis and the rationale for As(2)O(3) can be extended readily using all the HDAC associated diseases.

[Influence of different spliceosomes of overexpressed XBP-1 on differentiation of myeloma cells].

The aim of this study was to explore the effect of 2 different spliceosomes of X-box binding protein 1 (XBP-1), the spliced form XBP-1s and unspliced form XBP-1u, on myeloma cell differentiation and its mechanism. The overexpression plasmids pcDNA3.1-C-XBP1u and pcDNA3.1-C-XBP1s were constructed and transfected into myeloma cell line U266, RPMI8226. The morphology of U266 and RPMI 8226 cells was observed by means of light microscope, the expression rate of CD49e on cell surface was detected by flow cytometry, the ELISA was used to determine the changes of light chain protein level in supernatants of cell culture, the Western blot was used to assay the expression changes of XBP1u and XBP1s. The results showed that the overexpression of XBP1u could promote the myeloma cell differentiation morphologically displaying the maturation of plasmocytes, the CD49e positive expression rates on surface of U266 and RPMI8226 cells were obviously up-regulated from 9.02±0.3% and 5.17±0.92% in control group to 27.7±1.14% and 13.97±1.79% respectively (p<0.01), the levels of light chain protein in supernatants of U266 and RPMI 8226 cell cultures increased from 474.75±19.52 ng/ml and 289.44±6.19 ng/ml in control group to 692.34±21.17 ng/ml and 401.55±13.7 ng/ml respectively (p<0.01, p<0.05), while the above-mentioned parameters in the overexpressed XBP-1s showed no significant changes, which indicated no promotive effect of overexpressed XBP1s on myeloma cell differentiation. It is concluded that the up-regulation of XBP-1u expression plays an important role in the differentiation of myeloma cells.

[Mechanism study on low dose tunicamycin inducing myeloma cells differentiation via unfolded protein response].

OBJECTIVE: To explore the molecular mechanism of myeloma cell differentiation induced by low dose tunicamycin. METHOD: U266 and RPMI8226 cells were incubated with low dose tunicamycin for 72h. Surface CD49e expression was assayed by flow cytometer (FCM), light chain protein in the cell culture supernatant by ELISA, the unfolded protein response (UPR) related gene GRP78 and GRP94 by real time PCR, and XBP1u and XBP1s transcription and translation changes by real time PCR and Western blot. After XBP1u gene was interfered with small RNA, and constructed plasmid was transfected into myeloma cells to up-regulated gene XBP-1u and XBP-1s reseparately, the differentiation of myeloma cells was observed again. RESULTS: Small dose tunicamycin could induce both U266 and RPMI8226 myeloma cells differentiation. Compared with the control group, cell morphology changed to mature feature, the nucleo- cytoplasm ratio decreased and nucleolus reduced or disappearance, CD49e expression increased the light chain protein concentration of cell culture supernatant was up-regulated and UPR related gene GRP78 and GRP94 were up-regulated during the differentiation. XBP-1u was up-regulated at both transcription and translation level, while XBP-1s down-regulated. After XBP1u gene expression interfered with small RNA, cell differentiation was disturbed. Cell differentiation was induced while XBP-1u gene was up-regulated by plasmid transfection. CONCLUSION: Low dosage of tunicamycin could induce myeloma cell UPR and differentiation, while XBP-1u a key role during the process.

[Suppression of multiple myeloma tumor growth in vivo by transfection of platelet factor 4 or 17-70 cDNA].

This study was purposed to investigate the effects of viral vector-mediated gene transfer of platelet factor 4 (PF4) or 17-70 cDNA on cell growth of multiple myeloma (MM) in vivo. Full length and p17-70 cDNA of PF4 were cloned into virapower system to transfect packing cell line 293 and produce lentiviral vectors. 3 multiple myeloma cell lines were transferred platelet factor 4 or 17-70 cDNA by lentiviral vectors. SCID-rab mice models of multiple myeloma were established by injecting U266 multiple myeloma cells selected. The human light chain proteins and VEGF in serums of mice were detected every 2 weeks. The volumes and vascular density of tumors as well as survival time of mice were observed. The results showed that the MM cells expressing foreign genes were identified and screened. There were significant difference of VEGF levels in the supernatants of MM cells between each groups (p<0.01). The SCID-rab models of U266 cells were established successfully. There were significant differences in light chain protein and VEGF in serums among three groups (p<0.01). The light chain protein and VEGF in mice serums of 17-70 cDNA groups were less than that of PF4 group (p<0.01). The light chain protein and VEGF in mice serums of PF4 group were less than that of control group (p<0.01). There were significant differences in the tumor volumes and the vascular density of tumor among 3 groups (p<0.05). The results also showed that there were significant differences of overall survival in 3 different groups of SCID-rab MM models. The overall survival in control group was shortest as compared with other groups (p<0.05). It is concluded that the cell growth of multiple myeloma is suppressed in vivo by transfection of platelet factor 4 or 17-70 cDNA and the overall survival of transfected mice will be prolonged.