Adverse effects of cigarette filter silica on lungs: Comparison with natural crystalline silica particles.

As a common additive in cigarette filters, nanosilica has been implemented to reduce the release of harmful substances in cigarette smoke. However, the potential risk of occupational exposure for cigarette factory workers is unknown. We collected physical examination data from 710 cigarette factory workers to evaluate the adverse effects of cigarette filter silica exposure. We also established mouse models induced by cigarette filter silica and crystalline silica separately to compare the lung inflammation, pulmonary function, apoptosis, and fibrosis of the two models. Workers in the rolling and packing workshop exposed to cigarette filter silica had a higher rate of abnormal lung function (17.75%) than those in the cutting workshop (0.87%). Animal experiments showed that compared with the same dose of crystalline silica, cigarette filter silica resulted in higher levels of inflammatory factors in the bronchoalveolar lavage fluid (BALF) of mice at day 7, and lower levels of total lung capacity (TLC), inspiratory capacity (IC), vital capacity (VC), and forced vital capacity (FVC) in mice at day 28. Additionally, both exposed groups of mice showed increased levels of caspase 3, collagen I (Col-Ⅰ), α-smooth muscle actin (α-SMA) and hydroxyproline (HYP) in the lungs, as well as collagen accumulation and fibrous nodules at day 28, with no significant difference between the two groups. The results suggested that cigarette filter silica caused more severe early lung inflammation and late ventilation impairment than the same dose of crystalline silica. In the future, we need to pay more attention to nanosilica protection in cigarette factories to prevent pulmonary dysfunction in workers.

Atractylenolide III Ameliorated Autophagy Dysfunction via Epidermal Growth Factor Receptor-Mammalian Target of Rapamycin Signals and Alleviated Silicosis Fibrosis in Mice.

Atractylenolide III (ATL-III) is a major active constituent of the natural plant Atractylodes rhizome. Our previous study has shown that ATL-III may alleviate alveolar macrophage apoptosis via the inhibition of the mammalian target of rapamycin (mTOR)-mediated autophagy of human silicosis. Therefore, we aimed to further explore the function of ATL-III in autophagy, apoptosis, and pulmonary fibrosis by establishing the ATL-III-intervened silicosis mouse model in this study. Meanwhile, we sought and then verified potential autophagy-related signaling pathways by matching differentially expressed genes (attained by RNA sequencing) and the autophagy database. In this study, RNA-sequencing results implied that the epidermal growth factor receptor, the crucial upstream activator of mTOR, was seen as a potential autophagy-regulatory molecule in the ATL-III-intervened silicosis mouse model. The finding of this study was that ATL-III might improve the disorder of autophagic degradation via the activation of epidermal growth factor receptor-mTOR signals in the pulmonary tissue of the silicosis mouse model. ATL-III also alleviated cell apoptosis and silicotic fibrosis. Overall, we supposed that ATL-III might be a potential protective medicine, which had a regulatory effect on autophagy, for the intervention of silicotic fibrosis. In the future, the therapeutic drugs for silicosis should be further focused on the development and application of such natural autophagy agents.

Burnout among Chinese live streamers: Prevalence and correlates.

BACKGROUND: The prevalence of burnout among live streamers remains largely unknown. This study aims to investigate the prevalence and factors associated with burnout among Chinese live streamers. METHODS: A cross-sectional study recruited 343 full-time live streamers from 3 companies in Changsha city. Socio-demographic and occupational characteristics were collected using self-designed items. Job stress was assessed using the Job Content Questionnaire (JCQ-22), while supervisor and coworker support were evaluated using the last 8 items of the JCQ-22. Burnout was assessed using the 17-item Chinese version of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS). RESULTS: Our findings revealed that 30.6% of live streamers experienced burnout. Lower levels of education (OR = 2.65 and 3.37, p = 0,005 and 0.003), higher monthly income (OR = 10.56 and 11.25, both p = 0.003), being an entertainment-oriented streamer (OR = 2.13, p = 0.028), continuous walking during live streams (OR = 2.81, p = 0.006), significant drop in follower count (OR = 2.65, P = 0.006), live streaming during the daytime (OR = 3.75, p = 0.001), and higher support from supervisors and coworkers (OR = 3.66, p = 0.001) were positively associated with burnout. However, the effects of education and drop in followers on burnout were not significant in the multivariate logistic models (p = 0.321 and 0.988). CONCLUSIONS: Burnout among Chinese live streamers is associated with income, being an entertainment streamer, engaging in continuous walking during live streams, conducting live streams during the daytime, and experiencing excessive support from supervisors and coworkers.

Facile Synthesis of Carbon Dots from Amido Black 10b for Sensing in Real Samples.

Herein, a one-step hydrothermal synthesis method was adopted to fabricate carbon dots (CDs) from amido black 10b in a sodium hydroxide solution. The morphology and composition of the CDs were investigated by XRD, FTIR TEM, XPS, UV-vis, and fluorescence spectroscopy. The obtained CDs (AB-CDs) with an average diameter of 19.4 nm displayed a well-dispersed characteristic in aqueous solutions. The as-prepared CDs showed bright blue fluorescence and good photostability, with a high quantum yield of 24.1%. AB-CDs displayed a selective and noticeable turn-off response to Fe3+. Accordingly, the quantitative detection of Fe3+ was achieved in the range of 5-200 µmol L-1 with a detection limit of 1.84 µmol L-1. The fluorescence response mechanism of Fe3+ to AB-CDs was ascribed to static quenching due to the emergence of the ground-state complex. Moreover, ascorbic acid could restore the fluorescence of AB-CDs quenched by Fe3+ by reducing Fe3+ to Fe2+. The developed nanoprobe was used to detect ascorbic acid with a limit of detection of 7.26 µmol L-1 in the range of 20-300 µmol L-1. Furthermore, the developed sensing system was successfully applied for an Fe3+ assay in a lake water sample and ascorbic acid detection in a human urine sample. The AB-CD-based analytical system showed its latent practical value in the chemical analysis and bioanalytical fields.

Clinical Efficacy and In Vitro Drug Sensitivity Test Results of Azithromycin Combined With Other Antimicrobial Therapies in the Treatment of MDR P. aeruginosa Ventilator-Associated Pneumonia.

Objective: The aim of the research was to study the effect of azithromycin (AZM) in the treatment of MDR P. aeruginosa VAP combined with other antimicrobial therapies. Methods: The clinical outcomes were retrospectively collected and analyzed to elucidate the efficacy of different combinations involving azithromycin in the treatment of MDR-PA VAP. The minimal inhibitory concentration (MIC) of five drugs was measured by the agar dilution method against 27 isolates of MDR-PA, alone or in combination. Results: The incidence of VAP has increased approximately to 10.4% (961/9245) in 5 years and 18.4% (177/961) caused by P. aeruginosa ranking fourth. A total of 151 cases of MDR P. aeruginosa were included in the clinical retrospective study. Clinical efficacy results are as follows: meropenem + azithromycin (MEM + AZM) was 69.2% (9/13), cefoperazone/sulbactam + azithromycin (SCF + AZM) was 60% (6/10), and the combination of three drugs containing AZM was 69.2% (9/13). The curative effect of meropenem + amikacin (MEM + AMK) was better than that of the meropenem + levofloxacin (MEM + LEV) group, p = 0.029 (p < 0.05). The curative effect of cefoperazone/sulbactam + amikacin (SCF + AMK) was better than that of the cefoperazone/sulbactam + levofloxacin (SCF + LEV) group, p = 0.025 (p < 0.05). There was no significant difference between combinations of two or three drugs containing AZM, p > 0.05 (p = 0.806). From the MIC results, the AMK single drug was already very sensitive to the selected strains. When MEM or SCF was combined with AZM, the sensitivity of them to strains can be significantly increased. When combined with MEM and AZM, the MIC50 and MIC90 of MEM decreased to 1 and 2 ug/mL from 8 to 32 ug/mL. When combined with SCF + AZM, the MIC50 of SCF decreased to 16 ug/mL, and the curve shifted obviously. However, for the combination of SCF + LEV + AZM, MIC50 and MIC90 could not achieve substantive changes. From the FIC index results, the main actions of MEM + AZM were additive effects, accounting for 72%; for the combination of SCF + AZM, the additive effect was 40%. The combination of AMK or LEV with AZM mainly showed unrelated effects, and the combination of three drugs could not improve the positive correlation between LEV and AZM. Conclusion: AZM may increase the effect of MEM or SCF against MDR P. aeruginosa VAP. Based on MEM or SCF combined with AMK or AZM, we can achieve a good effect in the treatment of MDR P. aeruginosa VAP.

In Situ Generated Novel 1H MRI Reporter for ß-Galactosidase Activity Detection and Visualization in Living Tumor Cells.

For wide applications of the lacZ gene in cellular/molecular biology, small animal investigations, and clinical assessments, the improvement of noninvasive imaging approaches to precisely assay gene expression has garnered much attention. In this study, we investigate a novel molecular platform in which alizarin 2-O-ß-d-galactopyranoside AZ-1 acts as a lacZ gene/ß-gal responsive 1H-MRI probe to induce significant 1H-MRI contrast changes in relaxation times T 1 and T 2 in situ as a concerted effect for the discovery of ß-gal activity with the exposure of Fe3+. We also demonstrate the capability of this strategy for detecting ß-gal activity with lacZ-transfected human MCF7 breast and PC3 prostate cancer cells by reaction-enhanced 1H-MRI T 1 and T 2 relaxation mapping.

[Effect of laminar shear stress on the expression of matrix metalloproteinases-9 in rat bone marrow-derived mesenchymal stem cells].

This paper was designed to investigate the effect of laminar shear stress on matrix metalloproteinase -9 (MMP-9) expression in rat bone marrow-derived mesenchymal stem cells (MSCs), and the possible signal transduction mechanism involved. Rat bone marrow MSCs were isolated and cultured, then, exposed to laminar shear stress at indicated strengths such as low (5dyne/cm2), medium (15 dyne/cm2) and high (30 dyne/cm2) via parallel plate flow chamber. RT-PCR was used to analyze the expression of MMP-9. The signaling inhibitors such as Wortmannin (PI3K specific inhabitor), SB202190 (p38MAPK specific inhabitor), and PD98059 (ERK1/2 specific inhabitor) were used to investigate the possible mechanical signal transduction pathway. The results showed: (1) The expression of MMP-9 was weak in static state, however, MMP-9 expression increased when MSCs were exposed to 15 dyne/cm2 shear stress for 2 hours, and MMP-9 expression increased with the extension of stimulating time, and it reached the peak at 24 h; (2) MSCs were stimulated by shear stress for 2 hours at different strengths (5 dyne/cm2, 15 dyne/cm2, 30 dyne/cm2), and under all these conditions, the expression of MMP-9 increased, and reached the peak at 15 dyne/cm2; (3) After MSCs were pretreated by three kinds of signal pathway inhibitors, the expression of MMP-9 did not change obviously in Wortmannin group and PD98059 group, but it was significantly inhibited in SB202190 group. This study demonstrated that shear stress could induce the expression of MMP-9 in rat bone marrow-derived mesenchymal stem cells; the amount of MMP-9 expression was closely related to stimulating time and the strengths of shear stress; and p38MAPK signal pathway played a critical role during the process.

Regulation of insulin resistance and glucose metabolism by interaction of PIM kinases and insulin receptor substrates.

Insulin resistance is caused by various environmental and genetic factors leading to a number of serious health issues. Due to its multifactorial origin, molecular characterization may provide better tools for its effective treatment. On molecular level, dysregulation of signaling pathway by insulin receptor substrates (IRSs) is one of the most common reasons of this disease. IRSs are regulated by >50 serine/threonine kinases, which may have positive or negative effects on insulin sensitivity. Among these serine/threonine kinases, PIM kinases have garnered much attention as they not only affect insulin sensitivity by phosphorylating IRSs directly and/or indirectly but also alter the activities of their downstream molecules like PI3K, AKT, and mTOR. In this review, interactions of PIM kinases with IRSs and their downstream proteins and their action mechanism in the regulation of insulin resistance are elaborated. Furthermore, this review offers fundamental understandings of the role of PIM kinases in this signaling pathway.

Doxorubicin-induced toxicity to 3D-cultured rat ovarian follicles on a microfluidic chip.

Doxorubicin (DOX) has dose-dependent toxicity on ovarian follicles (OFs), and the inhibition of different signaling molecules along with the DOX application for enhancing its efficacy can also upsurge this toxicity. Therefore, it is strongly required to explore the mechanism of DOX-induced toxicity in 3D culture systems for protecting the OFs. A microfluidic chip was used to culture a single OF to identify the potential signaling molecules and their combined effects on OFs dynamically. The chip offers better 3D biomimetic microenvironment to the growing OF than 2D culture systems. The OFs cultured on the chip were treated with DOX and the inhibitors of Src, Ca2+, and PIM. Their mutual effects were studied on OFs growth and 17ß-estradiol secretion. Besides, the RNA levels of B4GALT2 and UNC5C genes of DOX-exposed OFs were detected by RT-qPCR, and TUNEL staining experiments were conducted to check the OF apoptosis. The results showed that DOX application reduced the OFs growth and hormone secretion and induced apoptosis in the OFs. Moreover, the DOX-induced toxic effects were enriched by Src and PIM inhibition, while reduced by the ER-Ca2+ channel inhibitor. This study specifically demonstrates the synergistic effects of some signaling molecules on DOX-mediated cellular functions of OFs and demands some meditative measures to decipher this toxicity for supporting the female endocrine and reproductive functions.

A Selective TRPC3 Inhibitor Pyr3 Attenuates Myocardial Ischemia/Reperfusion Injury in Mice.

An emerging body of evidence indicates that transient receptor potential TRP channels act as important mediators for a wide variety of physiological functions and are potential targets for drug discovery. Our previous study has identified transient receptor potential channel 3 (TRPC3) and TRPC6 as cation channels through which most of the damaging calcium enters, aggravates pathological changes in vivo and increases ischemia/reperfusion (I/R) injury in mice. This study aimed to verify the effects of TRPC3 inhibitor Pyr3 on myocardial I/R injury in mice. C57BL/6J wild-type male mice (8 to 12 weeks old) were anesthetized with 3.3% chloral hydrate. A murine I (30 min)/R (24 h) injury model was established by temporary occlusion of the left anterior descending (LAD) coronary artery. Pyr3 was administered at concentrations of 0, 2.5, 5, or 10 mg/kg via the right jugular vein 5 min before reperfusion. We observed that the selective TRPC3 inhibitor, 10 mg/kg Pyr3, significantly decreased the infarct size of left ventricle, and reduced the myocardial cell apoptosis rate and inflammatory response in mice. In a conclusion, TRPC3 can function as a candidate target for I/R injury prevention, and Pyr3 may directly bind to TRPC3 channel protein, inhibit TRPC3 channel activity, and improve TRPC3-related myocardial I/R injury. Pyr3 may be used for clarification of TRPC3 functions and for treatments of TRPC3-mediated diseases.

Pim-3 is expressed in endothelial cells and promotes vascular tube formation.

Pim-3 is a member of proto-oncogene Pim family that encodes serine/threonine kinases. Pim proteins regulate both apoptosis and cellular metabolism by phosphorylating their substrates. Here, we report for the first time that Pim-3 is highly expressed at mRNA and protein levels in endothelial cells (ECs). We found that Pim-3 is concentrated at the cellular lamellipodia and co-localized with focal adhesion kinase (FAK). Pim-3 was dispersed from lamellipodia when ECs were treated with cytochalasin D, an inhibitor of actin polymerization. In addition, small-interfering RNA (siRNA)-mediated gene knockdown of Pim-3 significantly impaired EC spreading, migration, and proliferation, leading to a reduction in tube-like structure formation in a Matrigel assay. These results provide the novel evidence that Pim-3 plays an essential role in EC spreading and migration, suggesting that Pim-3 may be an important molecular target for the development of small-molecule inhibitors of angiogenesis.

Nitrogen and chlorine co-doped carbon dots as probe for sensing and imaging in biological samples.

A facile one-step hydrothermal synthesis approach was proposed to prepare nitrogen and chlorine co-doped carbon dots (CDs) using l-ornithine hydrochloride as the sole precursor. The configuration and component of CDs were characterized by transmission electron microscopy and X-ray photoelectron and Fourier transform infrared spectroscopies. The obtained CDs (Orn-CDs) with a mean diameter of 2.1 nm were well monodispersed in aqueous solutions. The as-prepared CDs exhibited a bright blue fluorescence with a high yield of 60%, good photostability and low cytotoxicity. The emission of Orn-CDs could be selectively and effectively suppressed by Fe3+. Thus, a quantitative assay of Fe3+ was realized by this nanoprobe with a detection limit of 95.6 nmol l-1 in the range of 0.3-50 µmol l-1. Furthermore, ascorbic acid could recover the fluorescence of Orn-CDs suppressed by Fe3+, owing to the transformation of Fe3+ to Fe2+ by ascorbic acid. The limit of detection for ascorbic acid was 137 nmol l-1 in the range of 0.5-10 µmol l-1. In addition, the established method was successfully applied for Fe3+ and ascorbic acid sensing in human serum and urine specimens and for imaging of Fe3+ in living cells. Orn-CD-based sensing platform showed its potential to be used for biomedicine-related study because it is cost-effective, easily scalable and can be used without additional functionalization and sample pre-treatment.

Doxorubicin Induces ER Calcium Release via Src in Rat Ovarian Follicles.

Although doxorubicin has been widely used as an anticancer drug, it has dose-dependent toxic effects on ovarian follicle development and apoptosis, oocyte maturation, and hormone secretion. Ca2+ signaling also has vital roles in the same cellular functions of ovarian follicles, indicating a strong link with doxorubicin-induced ovarian toxicity. In the current project, doxorubicin-induced Ca2+ alternations in cultured rat ovarian follicles have been explored with the fluorescence resonance energy transfer technology. The results reveal that doxorubicin enhances the cytosolic Ca2+ level smoothly. Further experiments confirm that the endoplasmic reticulum (ER) calcium, but not the extracellular calcium influx, is the main source of intracellular calcium increase. Moreover, Src kinase activation could be the upstream of doxorubicin-induced ER calcium release. Therefore, this project demonstrates that doxorubicin increases the cytosolic Ca2+ mainly by releasing calcium from ER via Src kinase activation in ovarian follicles, which provides deeper understanding of doxorubicin-induced ovarian toxicity.

Acinetobacter baumannii Ventilator-Associated Pneumonia: Clinical Efficacy of Combined Antimicrobial Therapy and in vitro Drug Sensitivity Test Results.

Objective: To evaluate therapeutic efficacy of different combined antimicrobial treatments against Acinetobacter baumannii ventilator-associated pneumonia (VAP). Methods: Clinical outcomes were retrospectively analyzed to elucidate the efficacy of four combined antimicrobial regimens. The chessboard and micro broth dilution methods determined the minimum inhibitory concentrations (MICs) of four antiseptic drugs singly used and combined two drugs against 36 isolates of multidrug-resistant (MDR) A. baumannii. Results: The incidence of VAP was approximately 6.9% (237/3424) between January 1, 2015 and December 31, and 35.9% (85/237) of the cases were caused by A. baumannii. Among these cases, 60 belonged to AB-VAP, for whom antimicrobial treatment plan was centralized and clinical data was complete. Moreover, all 60 strains of A. baumannii were MDR bacteria from reports microbiological laboratory. Resistance rate was lowest for amikacin (68.3%) and ampicillin sulbactam (71.7%). Resistance rate for imipenem increased from 63.2 to 90.9% during the 3 years. However, in these 60 cases of AB-VAP, the combination between 4 antibiotics was effective in most cases: the effective rate was 75% (18/24) for sulbactam combined with etilmicin, 71.4% (10/14) for sulbactam combined with levofloxacin, 72.7% (8/11) for meropenem combined with etilmicin, and 63.6% (7/11) for meropenem combined with levofloxacin. There was no statistical difference between four regimens (P > 0.05). Sulbactam combined with etilmicin decreased 1/2 of MIC50 and MIC90 of sulbactam while the decreases in etilmicin were more obviously than single drug. When adopting meropenem combined with levofloxacin or etilmicin, the MIC of meropenem reduced to 1/2 of that in applying single drug. As for sulbactam or meropenem combined with levofloxacin, it also lessened the MIC50 of levofloxacin to 1/2 of that for single drug. FIC results suggested that the effects of four combined antimicrobial regimens were additive or unrelated. When sulbactam was combined with etimicin, the additive effect was 63.89%. Conclusion: Drug combination sensitivity test in vitro may be helpful for choosing antimicrobial treatment plans. Sulbactam or meropenem as the basis of treatment regimens can function as the alternatives against AB-VAP. Sulbactam combined with etimicin has been regarded as a recommended regimen in Suizhou, Hubei, China.

Biomechanical properties of ascending aorta and pulmonary trunk in pigs and humans.

BACKGROUND: This study aims to obtain the biomechanical properties of ascending aorta and pulmonary trunk between healthy humans and pigs of different months, so as to provide necessary biomechanical experimental basis for anastomosing blood vessel in pig-to-human heart xenotransplantation. METHODS: Ascending aorta and pulmonary trunks of the six deceased donors (male 4, female 2) and 42 Chinese Hubei white pigs aged 1-7 months were performed biomechanical test. The blood vessel was given periodic permanent loading and unloading, and repeated force-deformation data were obtained. The elastic properties of the blood vessels were obtained by curve from experimental data. RESULTS: The biomechanical material constant of ascending aorta and pulmonary trunk of pigs did not increase with the increase of age (F = 14.569, P = 0.126). The biomechanical material constant of humans was basically similar to that of pigs aged 1-7 months (F = 12.264, P = 0.225). The elastic modulus was the biggest in pigs aged 7 months in comparison with that in other ages (F = 27.425, P = 0.032). There was no significant difference of elastic modulus of corresponding blood vessel between humans and pigs of different months (F = 17.328, P = 0.215). CONCLUSIONS: Our present study suggests that there was no significant difference of elastic properties of ascending aorta and pulmonary trunks between humans and pigs. From biomechanical aspects, anastomosis of corresponding ascending aorta and pulmonary trunks in the process of pig-to-human heart xenotransplantation may be feasible.

Quantitative analysis of the microstructure of human umbilical vein for assessing feasibility as vessel substitute.

We explored the feasibility of human umbilical vein (HUV) as a small-caliber vessel substitute. HUVs of 50 fetuses were collected on spontaneous miscarriage or labor with the pregnant women's permission. Gestational age ranged 24-42 weeks, and parturients were 20-30 years old. Each sample was sliced into 5 mum frozen transverse sections and stained with hematoxylin-eosin (HE), Weigert, aniline blue, and orange yellow G. The geometric morphological indexes and microstructural component were measured by a computer image analysis system. The media thickness was 0.186, 0.203, 0.237, 0.264, and 0.268 mm at 24-27, 28-32, 33-36, 37-40, and 41-42 weeks, respectively (F = 133.35, p < 0.01); diameters were 1.861, 1.962, 2.303, 2.464, and 2.465 mm (F = 37.35, p < 0.01), respectively. The media thickness and diameter of HUVs increased with gestational age. The elastin content of media increased at 24-40 weeks, but the collagen content and collagen/elastin (C/E) ratio decreased. Elastin content in the proximal segment was higher than in the distal segment [10.16, 6.36 Aa%, (Aa% is the unit of relative content, ie, the ratio of absolute areas to the total tested area of smooth muscle, collagen and elastin in the vascular wall) F = 5.77-12.3, p < 0.05], with the collagen to elastin (C/E) ratio increasing from the proximal to the distal segment (F = 7.63-13.4, p < 0.05). Our results suggest that the microstructural component of HUVs (2.0-3.0 mm caliber) at 37-40 weeks of gestation was similar to that of the small-caliber arteries and had moderate amounts of collagen and elastin and good elasticity, i.e., a good C/E ratio; therefore, HUV may be a substitute for small-caliber arteries (e.g., brachial, ulnar, radial, right coronary, anterior tibial, and posterior tibial). HUV is one of several graft materials that may be used when autogenous saphenous vein is absent or inadequate.

PIM Kinases and Their Relevance to the PI3K/AKT/mTOR Pathway in the Regulation of Ovarian Cancer.

Ovarian cancer is a medical term that includes a number of tumors with different molecular biology, phenotypes, tumor progression, etiology, and even different diagnosis. Some specific treatments are required to address this heterogeneity of ovarian cancer, thus molecular characterization may provide an important tool for this purpose. On a molecular level, proviral-integration site for Moloney-murine leukemia virus (PIM) kinases are over expressed in ovarian cancer and play a vital role in the regulation of different proteins responsible for this tumorigenesis. Likewise, the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway is also a central regulator of the ovarian cancer. Interestingly, recent research has linked the PIM kinases to the PI3K/AKT/mTOR pathway in several types of cancers, but their connection in ovarian cancer has not been studied yet. Once the exact relationship of PIM kinases with the PI3K/AKT/mTOR pathway is acquired in ovarian cancer, it will hopefully provide effective treatments on a molecular level. This review mainly focuses on the role of PIM kinases in ovarian cancer and their interactions with proteins involved in its progression. In addition, this review suggests a connection between the PIM kinases and the PI3K/AKT/mTOR pathway and their parallel mechanism in the regulation of ovarian cancer.

Coculture with endothelial cells enhances vascular smooth muscle cell adhesion and spreading via activation of beta1-integrin and phosphatidylinositol 3-kinase/Akt.

The interactions between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) play significant roles in the homeostasis of the blood vessel during vascular remodeling. Cell adhesion and spreading are an essential process for VSMC migration, survival and proliferation in the events of vascular physiology and pathophysiology. However, effects of ECs on adhesion and spreading of VSMCs have not been characterized yet. Here, the interaction of ECs and VSMCs on adhesion and spreading of VSMCs were investigated by using a coculture system. The results showed that VSMCs cocultured with ECs exhibited a significant increase in the number of adherent and spreading cells, and much more mRNA (twofold, P<0.01) and protein (threefold, P<0.05) expression of beta(1)-integrin comparing to the control, i.e., VSMCs cultured alone. Furthermore, the enhanced functional activity of beta(1)-integrin expression was confirmed by FACS. A beta(1)-integrin blocking antibody (P5D2) could inhibit the EC-induced VSMC adhesion and spreading. It was demonstrated that in correspondence with enhanced cell adhesion, ECs also prompted focal adhesion complex assembly and stress fiber formation of VSMCs. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway was more pronouncedly activated in response to VSMC attachment. Our results for the first time show that coculture with ECs enhances VSMC adhesion and spreading by up-regulating beta(1)-integrin expression and activating the PI3K/Akt pathway, suggesting that the interaction between ECs and VSMCs serves an important role in vascular homeostasis and remodeling.

Frequency-dependent phenotype modulation of vascular smooth muscle cells under cyclic mechanical strain.

Phenotype transformation of vascular smooth muscle cells (VSMCs) is known to be modulated by mechanical strain. The present study was designed to investigate how different frequencies of mechanical strain affected VSMC phenotype. VSMCs were subjected to the strains of 10% elongation at 0, 0.5, 1 and 2 Hz for 24 h using a Flexercell strain unit. VSMC phenotype was assessed by cell morphology, measurement of two-dimensional cell area, Western blotting for protein and RT-PCR for mRNA expression of differentiation markers. Possible protein kinases involved were evaluated by Western blotting with their specific antibodies. The strains at certain frequencies could induce a contractile morphology in VSMC with almost perpendicular alignment to the strain direction. The strains also regulated protein and mRNA expression of several differentiation markers, as well as the activation of extracellular signal-regulated kinases (ERKs), p38 MAP kinase and protein kinase B (Akt) in a frequency-dependent manner. Furthermore, the inhibition of the p38 pathway could block the frequency-induced phenotype modulation of VSMCs, but not inhibition of ERK or Akt pathways. These results indicate that the frequency of cyclic strain can result in the differentiated phenotype of VSMCs, and it is mediated at least partly by the activation of the p38 pathway.

Role of Rho-specific guanine nucleotide dissociation inhibitor α regulation in cell migration.

Cell migration is a vital process for many physiological and pathological events, and Rho GTPases have been confirmed as key factors in its regulation. The most studied negative regulator of Rho GTPases, Rho-specific guanine nucleotide dissociation inhibitor α (RhoGDIα), mediates cell migration through altering the overall expression and spatiotemporal activation of Rho GTPases. The RhoGDIα-Rho GTPases dissociation can be mediated by signal pathways targeting RhoGDIα directly. This review summarizes the research about the regulation of RhoGDIα during cell migration, which can be in a Rho GTPases association independent manner. Non-kinase proteins regulation, phosphorylation, SUMOylation and extracellular environmental factors are classified to discuss their direct signal regulations on RhoGDIα, which provide varied signal pathways for selective activation of Rho GTPases in cell migration.