Phase distribution and circular dichroism switchable terahertz chiral metasurface.

Chiral metasurfaces have many applications in the terahertz (THz) band, but they still lack modulation flexibility and functionality expansion. This paper presents a terahertz chiral metasurface with switchable phase distribution and switchable circular dichroism (CD). The metasurface unit consists of a metallic inner ring embedded in vanadium oxide and a vanadium oxide outer ring, state switching by thermal control of vanadium oxide and a change in the frequency of the incident wave. Based on the switchable phase distribution, we designed a focusing vortex beam generator with adjustable focal lengths through simulation. Based on the switching CD capability, we simulate its mode switching in near-field imaging using numerical simulation, and innovatively propose an optical encryption method. Utilizing the chiral property, we also designed dual-channel switchable holographic imaging in the same frequency band, which combined with the state change of VO2 can realize a total of 4 holograms switching. Our proposed metasurface is expected to provide new ideas for the study of optical encryption and wavefront modulation of dynamics.

A population-based study exploring association of parasomnia symptoms with sleep onset delay among school-aged children.

OBJECTIVE: Parasomnia is potentially implicated in sleep pattern and sleep architecture, however, evidence is quite limited. This study aimed to investigate the association between parasomnia symptoms and sleep onset delay among children through a large epidemiological study. METHODS: Two rounds of cross-sectional studies were conducted among 21,704 children aged 3-11; one taking place in Shanghai and the other in Sanya, Hainan province. Children's sleep characteristics were evaluated using the Children's Sleep Habits Questionnaire (CSHQ). Propensity score matching was adopted to balance the difference of covariates, and the logistic regression models were implemented to examine the associations between parasomnia symptoms and sleep onset delay. RESULTS: A total of 38.2 % of children had sleep onset delay. Parasomnias, especially non rapid eye movement (NREM) and rapid eye movement (REM) parasomnia symptoms, were associated with an increased risk of sleep onset delay (Sleep Walking: OR = 1.55; Sleep Terror: OR = 1.34; Nightmare: OR = 1.37, all p˂0.001). The similar findings were observed in stratified analyses according to sleep duration, and the association was pronounced in sleep sufficiency group (Sleep Walking: OR = 1.62; Sleep Terror: OR = 1.35; Nightmare: OR = 1.35, all p˂0.001). Moreover, a dose-dependent pattern was observed, in which cumulative parasomnia symptoms were associated with increasing risk of sleep onset delay (2 symptoms: OR = 1.19; ≥3 symptoms: OR = 1.40; by comparison with ≤1 symptom). All these findings were also similarly observed in the propensity score matching sample. Moreover, the associations were generally established in both Shanghai and Sanya children. CONCLUSIONS: Parasomnia symptoms were associated with a higher risk of sleep onset delay independently of sleep duration among children. More studies are needed to enrich the current evidence, thus further clarifying the association and interaction among different sleep parameters.

Assessing causal relationships between gut microbiota and asthma: evidence from two sample Mendelian randomization analysis.

Background: Accumulating evidence has suggested that gut microbiota dysbiosis is commonly observed in asthmatics. However, it remains unclear whether dysbiosis is a cause or consequence of asthma. We aimed to examine the genetic causal relationships of gut microbiota with asthma and its three phenotypes, including adult-onset asthma, childhood-onset asthma, and moderate-severe asthma. Methods: To elucidate the causality of gut microbiota with asthma, we applied two sample Mendelian randomization (MR) based on the largest publicly available genome-wide association study (GWAS) summary statistics. Inverse variance weighting meta-analysis (IVW) was used to obtain the main estimates; and Weighted median, MR-Egger, Robust Adjusted Profile Score (MR-RAPS), Maximum likelihood method (ML), and MR pleiotropy residual sum and outlier (MR-PRESSO) methods were applied in sensitivity analyses. Finally, a reverse MR analysis was performed to evaluate the possibility of reverse causation. Results: In the absence of heterogeneity and horizontal pleiotropy, the IVW method revealed that genetically predicted Barnesiella and RuminococcaceaeUCG014 were positively correlated with the risk of asthma, while the association between genetically predicted CandidatusSoleaferrea and asthma was negative. And for the three phenotypes of asthma, genetically predicted Akkermansia reduced the risk of adult-onset asthma, Collinsella and RuminococcaceaeUCG014 increased the risk of childhood-onset asthma, and FamilyXIIIAD3011group, Eisenbergiella, and Ruminiclostridium6 were correlated with the risk of moderate-severe asthma (all P<0.05). The reverse MR analysis didn't find evidence supporting the reverse causality from asthma and its three phenotypes to the gut microbiota genus. Conclusion: This study suggested that microbial genera were causally associated with asthma as well as its three phenotypes. The findings deepened our understanding of the role of gut microbiota in the pathology of asthma, which emphasizes the potential of opening up a new vista for the prevention and diagnosis of asthma.

Association of residential greenness with chronotype among children.

BACKGROUND: The association between residential greenness and chronotype remains unclear, especially among children. The current study aimed to explore the associations between residential greenness and chronotype parameters in children and examine potential pathways for these associations. METHODS: In this cross-sectional study, 16,421 children ages 3-12 were included. Two satellite-derived vegetation indices, i.e., the normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI), were used to estimate residential greenness. The mid-sleep point on a workday (MSW) and the mid-sleep point on free days (MSF) were considered. And mid-sleep time on free days adjusted for sleep debt (MSFsc) was used as an indicator of chronotype. In addition to multivariable linear regression models, subgroup analyses were conducted to explore effect modifiers, and mediation analyses were used to explore possible mediating mechanisms of air pollutants underlying the associations. RESULTS: An interquartile range (IQR) increase in both NDVI500-m and EVI500-m was significantly associated with an earlier MSFsc of -0.061 (95 % confidence interval (CI): -0.072, -0.049) and -0.054 (95 % CI: -0.066, -0.042), respectively. Non-linear dose response relationships were discovered between greenness indices and MSFsc and MSF. The results of stratified analyses showed the effect of residential greenness on MSW was stronger among primary school children and individuals with higher household income than among kindergarten children and those with lower household income. The joint mediation effects of PM2.5, PM1, PM10, NO2, and SO2 on the associations of NDVI500-m and EVI500-m with MSFsc were 89.6 % and 76.0 %, respectively. CONCLUSIONS: Higher levels of residential greenness may have beneficial effects on an earlier chronotype in the child population, by reducing the effects of air pollutants, especially PM2.5. Our research hopes to promote the deployment of green infrastructure and healthy urban design strategies.

Individual and joint association of phenols, parabens, and phthalates with childhood lung function: Exploring the mediating role of peripheral immune responses.

The functioning of the respiratory system can be interfered with by exposure to mixtures of environmental chemicals, however, the evidence is still ambiguous. We evaluated the association of exposure to mixtures of 14 chemicals, including 2 phenols, 2 parabens, and 10 phthalates, with four major lung function metrics. Based on data from the National Health and Nutrition Examination Survey 2007-2012, this analysis was conducted among 1462 children aged 6-19 years. Linear regression, Bayesian kernel machine regression, quantile-based g-computation regression, and a generalized additive model were performed to estimate the associations. Mediation analyses were performed to investigate plausible biological pathways mediated by immune cells. Our results indicated that the phenols, parabens, and phthalates mixture was negatively related to lung function parameters. And BPA and PP were identified as important contributors to negative associations with FEV1, FVC, and PEF, with non-linear relationships observed between BPA and those outcomes. The most influential factor for a probable FEF25-75 % decline was MCNP. BPA, and MCNP had an interaction effect on FEF25-75 %. The association of PP with FVC and FEV1 has been postulated to be mediated by neutrophils and monocytes. The findings offer insights into the associations of chemical mixtures with respiratory health and the possible driving mechanism, which would be of significance in adding novel evidence of the role of peripheral immune responses, as well as calling for remediation actions to be prioritized during childhood.

Independent and combined associations of multiple-heavy-metal exposure with lung function: a population-based study in US children.

Previous research has found relationships between some single metals and lung function parameters. However, the role of simultaneous multi-metal exposure is poorly understood. The crucial period throughout childhood, when people are most susceptible to environmental dangers, has also been largely ignored. The study aimed to evaluate the joint and individual associations of 12 selected urinary metals with pediatric lung function measures using multi-pollutant approaches. A total of 1227 children aged 6-17 years from the National Health and Nutrition Examination Survey database of the 2007-2012 cycles were used. The metal exposure indicators were 12 urine metals adjusted for urine creatinine, including arsenic (As), barium (Ba), cadmium (Cd), cesium (Cs), cobalt (Co), mercury (Hg), molybdenum (Mo), lead (Pb), antimony (Sb), thallium (Tl), tungsten (Tu), and uranium (Ur). The outcomes of interest were lung function indices, including the 1st second of a forceful exhalation (FEV1), forced vital capacity (FVC), forced expiratory flow between 25 and 7% of vital capacity (FEF25-75%), and peak expiratory flow (PEF). Multivariate linear regression, quantile g-computation (QG-C), and Bayesian kernel machine regression models (BKMR) were adopted. A significantly negative overall effect of metal mixtures on FEV1 (ß = - 161.70, 95% CI - 218.12, - 105.27; p < 0.001), FVC (ß = - 182.69, 95% CI - 246.33, - 119.06; p < 0.001), FEF25-75% (ß = - 178.86 (95% CI - 274.47, - 83.26; p < 0.001), and PEF (ß = - 424.17, 95% CI - 556.55, - 291.80; p < 0.001) was observed. Pb had the largest negative contribution to the negative associations, with posterior inclusion probabilities (PIPs) of 1 for FEV1, FVC, and FEF25-75%, and 0.9966 for PEF. And Pb's relationship with lung function metrics showed to be nonlinear, with an approximate "L" shape. Potential interactions between Pb and Cd in lung function decline were observed. Ba was positively associated with lung function metrics. Metal mixtures were negatively associated with pediatric lung function. Pb might be a crucial element. Our findings highlight the need for prioritizing children's environmental health to protect them from later respiratory disorders and to guide future research into the toxic mechanisms of metal-mediated lung function injury in the pediatric population.

High dose isoleucine stabilizes nuclear PTEN to suppress the proliferation of lung cancer.

PURPOSE: Cancer cells require a supply of amino acids, particularly essential amino acids such as branched-chain amino acids (BCAAs, i.e., valine, leucine, and isoleucine), to meet the increased nutrient demands of malignant tumors. The cell-autonomous and non-autonomous roles of altered BCAA supply have been implicated in cancer progression. The critical proteins involved in BCAA uptake, transport, metabolism, etc. serve as potential therapeutic biomarkers in human cancers. Here, we summarize the potential anti-tumor mechanism of BCAA by exploring the chain reaction triggered by increased BCAA supply in the tumor. METHOD: A system-wide strategy was employed to provide a generic solution to establish the links between BCAA and cancer based on comprehensive omics, molecular experimentation, and data analysis. RESULTS: BCAA over-supplementation (900 mg/kg) significantly inhibited tumor growth and reduced tumor burden, with isoleucine having the most pronounced effect. Surprisingly, isoleucine inhibited tumor growth independently of mTORC1 activation, a classical amino acid sensor. Exploratory transcriptome analysis revealed that Phosphatase and tensin homolog (PTEN) is the critical factor in the anti-tumor effect of isoleucine. By inhibiting PTEN ubiquitination, isoleucine can promote PTEN nuclear import and maintain PTEN nuclear stability. Interestingly, this process was regulated by isoleucine-tRNA ligase, cytoplasmic (IARS), a direct target of isoleucine. We demonstrated the enhanced interaction between IARS and PTEN in the presence of excess isoleucine. At the same time, IARS knockout leads to loss of isoleucine tumor suppressor ability. CONCLUSION: Overall, our results provide insights into the regulation of the IARS-PTEN anti-tumor axis by isoleucine and reveal a unique therapeutic approach based on enhancing cellular isoleucine supply.

Optical interference effect in the hybrid quantum dots/two-dimensional materials: photoluminescence enhancement and modulation.

The optical interference effect originating from the multiple reflections between the two-dimensional (2D) materials and the substrates has been used to dramatically enhance their Raman signal. However, this effect in the hybrid structures of colloidal quantum dots (QD) coupled to 2D materials is always overlooked. Here we theoretically prove that the photoluminescence (PL) intensities of the QD films in the QD-2D hybrid structures can be strongly enhanced and modulated by the optical interference effect between QD and 2D interfaces, breaking the inherent standpoint that PL intensities of the QD films are always prominently quenched in these hybrid structures. The theoretical predictions have been well confirmed by experimental measurements of PL properties of CdSe/ZnS and CdSeTe/ZnS QD on different 2D materials (such as WSe2, MoS2, and h-BN). PL intensities of these QD films have been periodically modulated from almost disappearing to strong enhancement (with the enhancement of about 6 times). The optical interference effect uncovered in this work enables a powerful method to manipulate the PL property of the QD films in the different QD-2D hybrid structures. These results can boost the optical performance of the QD-based electronic and optoelectronic devices in the hybrid QD-2D structures.

Relationships between Sleep Duration, Timing, Consistency, and Chronotype with Myopia among School-Aged Children.

Background: The role of sleep in childhood myopia has been a research focus; however, the existing evidence is conflicting on sleep duration and timing, and as yet, no studies involve sleep consistency and chronotype. This study is done to make multiple-perspective analyses on the associations between sleep variables and myopia. Methods: A population-based cross-sectional study was conducted in Shanghai, China, which included 10,142 school-aged children (7-12 years old, 53.2% boys). The Chinese version of the Children's Sleep Habits Questionnaire (CSHQ) was used to assess sleep variables. Propensity score matching was adopted to balance the difference of covariates between nonmyopic and myopic groups. Logistic regression models were implemented to examine the associations between sleep variables and myopia. Results: Sleep duration and timing, mainly during weekdays, were correlated with myopia in a dose-dependent pattern, in which longer sleep duration was associated with decreased risk of myopia (9-10 hours/day: odds ratio (OR) = 0.87; ≥10 hours/day: OR = 0.77; by comparison with <9 hours/day); later bedtime (9 pm to 9:30 pm: OR = 1.46; 9:30 pm to 10 pm: OR = 1.51; 10 pm and after: OR = 2.08; by comparison with before 9 pm) and later wake-up time (7 am and after: OR = 1.36; by comparison with before 6:30 am) increased the risk (all P < 0.05). Moreover, longer weekend catch-up sleep duration and intermediate and evening chronotype were positively correlated with myopia, while social jetlag was associated with a lower odds of myopia. All these findings were also similarly observed in the matching sample. Conclusions: Multiple dimensions of sleep were involved in childhood myopia. In addition to sleep duration and timing, sleep consistency and chronotype were also strictly related to myopia. More studies are needed to enrich the current evidence, thus further clarifying the association between sleep and childhood myopia.

Exploring genetic association of insomnia with allergic disease and asthma: a bidirectional Mendelian randomization study.

BACKGROUND: Insomnia is highly prevalent among patients with allergic disease and asthma; however, few studies have investigated their causal relationship. We aim to explore the causal association between insomnia and allergic disease/asthma by performing bidirectional Mendelian randomization (MR) study. METHODS: Instrumental variables were constructed using single nucleotide polymorphisms (SNPs). Summary statistics for insomnia, allergic disease, and asthma were obtained from four large-scale genome-wide association studies (GWAS) of European ancestry. The pleiotropy analysis was applied by using the MR-Egger intercept test and the MR pleiotropy residual sum and outlier (MR-PRESSO) test. MR analyses were conducted by using inverse variance weighted (IVW), weighted median, and MR-Egger method. RESULTS: Based on the multiplicative random effects IVW method, the MR analysis showed that genetically predicted insomnia was causally associated with an increased risk of allergic disease [odds ratio (OR) = 1.054, 95% confidence interval (CI) = 1.031-1.078, P = 3.817 × 10-06], asthma (OR = 1.043, 95% CI = 1.010-1.077, P = 9.811 × 10-03), moderate-severe asthma (OR = 1.168, 95% CI = 1.069-1.277, P = 6.234 × 10-04), and adult-onset asthma (OR = 1.086, 95% CI = 1.037-1.138, P = 4.922 × 10-04). In bidirectional analyses, we did not find evidence supporting the reverse causality relations. CONCLUSIONS: Our MR study suggested that genetically predicted insomnia was the risk factor for allergic disease and asthma. Improving sleep quality could be one of the cornerstones in the prevention of allergic disease and asthma.

Centella asiatica (L.) Urb. attenuates cardiac hypertrophy and improves heart function through multi-level mechanisms revealed by systems pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Cardiac hypertrophy (CH) is an incurable heart disease, contributing to an increased risk of heart failure due to the lack of safe and effective strategies. Therefore, searching for new approaches to treat CH is urgent. Centella asiatica (L.) Urb. (CA), a traditional food and medicinal natural plant, has been turned out to be effective in the treatment of cardiovascular disease, but its efficacy and potential mechanisms in alleviating CH have not yet been investigated. AIM OF STUDY: In this study, we aimed to elucidate the multi-level mechanisms underlying the effect of CA against CH. STUDY DESIGN AND METHODS: A systems pharmacology approach was employed to screen active ingredients, identify potential targets, construct visual networks and systematically investigate the pathways and mechanisms of CA for CH treatment. The cardiac therapeutic potential and mechanism of action of CA on CH were verified with in vivo and in vitro experiments. RESULTS: Firstly, we demonstrated the therapeutic effect of CA on CH and then screened 13 active compounds of CA according to the pharmacokinetic properties. Then, asiatic acid (AA) was identified as the major active molecule of CA for CH treatment. Afterwards, network and functional enrichment analyses showed that CA exerted cardioprotective effects by modulating multiple pathways mainly involved in anti-apoptotic, antioxidant and anti-inflammatory processes. Finally, in vivo, the therapeutic effects of AA and its action on the YAP/PI3K/AKT axis and NF-κB signaling pathway were validated using an isoproterenol-induced CH mouse model. In vitro, AA decreased ROS levels in hydrogen peroxide-treated HL-1 cells. CONCLUSION: Overall, the multi-level mechanisms of CA for CH treatment were demonstrated by systems pharmacology approach, which provides a paradigm for systematically deciphering the mechanisms of action of natural plants in the treatment of diseases and offers a new idea for the development of medicinal and food products.

Pre-, Intra-, and Post-Operative Factors for Kidney Injury of Patients Underwent Cardiac Surgery: A Retrospective Cohort Study.

BACKGROUND Kidney injury is common in patients who have undergone cardiac surgery, and it has high morbidity and mortality. The objective of the study was to identify pre-, intra-, and post-operative risk factors responsible for kidney injury among patients who had undergone cardiac surgery. MATERIAL AND METHODS Patients (n=1468) who had undergone cardiac surgery were stratified into those with kidney injury (n=488) and those without kidney injury (n=980) using the KDIGO (Kidney Disease: Improving Global Outcomes) criteria. Data of pre-, intra- and post-operative variables were collected and analyzed. RESULTS Acute kidney injury occurred in 33.2% of study patients. Patients with post-operative acute kidney injury had older age, comorbidities, higher preoperative serum creatinine, coronary artery bypass grafting, longer operation time, high cardiopulmonary bypass and cross-clamping time, low central venous pressure, and prolonged mechanical ventilation as compared to patients without kidney injury (P<0.05 for all). Age >65 years (OR 1.4), preoperative hypertension (OR 2.0), preoperative anemia (OR 2.3), preoperative low ejection fraction (OR 3.7), Charlson comorbidity index >2 (OR 2.5), longer cardiopulmonary bypass time (OR 4.0), blood transfusions (OR 2.1), postoperative hypotension (OR 5.2), and low central venous pressure (OR 8.1) were responsible for kidney injury. Mortality of patients with kidney injury was significantly higher than those without acute kidney injury (52 versus 1, P<0.001). CONCLUSIONS Appropriate and effective control of pre-, intra-, and post-operative variables can reduce the risk of kidney injury development in patients following cardiac surgeries.

Removal kinetics of petroleum hydrocarbons from low-permeable soil by sand mixing and thermal enhancement of soil vapor extraction.

Thermally enhanced remediation of n-alkanes-contaminated silty soil mixed with coarse quartz sands was demonstrated in a laboratory cylindrical tank with diameter of 40 cm and depth of 30 cm. The removal kinetics of semi-volatile n-alkanes (C10, C11, C13-16) under three pulsed heating operations of soil vapor extraction (SVE) was investigated. CMG-STARS software was adopted to simulate the dynamics of heat transfer within the soil column. The results indicated the dramatic increase of air permeability of soil and acceleration of heat transfer after introduction of sand, with the result of achieving rapid soil remediation. Gas-phase transfer of n-alkanes mainly occurred when average soil temperature was ≥100 °C. At the end of remediation with soil subjected to heating for 30.8 h (total running time), the average soil concentration of total n-alkanes was reduced from initial 3106.5 to 202.4 mg/kg, corresponding to 93.4% of mass removal. The residual n-alkanes of C10, C11, C13 and C14 in all collected soil samples were declined to levels of lower than 10 mg/kg. Most of the soil concentration-gradient curves for n-alkanes tested almost coincided with their isothermal contours, indicating the key impact of thermal drive force on contaminant transfer.

Early increase of neutrophil-to-lymphocyte ratio predicts 30-day mortality in patients with spontaneous intracerebral hemorrhage.

AIMS: To examine whether early rise of neutrophil-to-lymphocyte ratio (NLR) after patient hospitalization correlates with 30-day mortality in patients with spontaneous intracerebral hemorrhage (ICH). METHODS: This retrospective study included all patients receiving treatment for spontaneous ICH between January 2015 and September 2016 at the Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Sciences in Shanghai, China. NLR was determined at admission (T1), at 24-48 hours (T2) and 5-7 days (T3). NLR and clinicopathologic features were compared between those who survived for >30 days vs not. Multivariate regression was used to identify risk factors for 30-day mortality. RESULTS: A total of 275 subjects were included in the analysis: 235 survived for at least 30 days; the remaining 40 subjects died within 30 days. The patients who died within 30 days had higher ICH score, larger ICH volume, and lower GCS score (all P < 0.05). In comparison with the baseline (NLRT1 ), NLR at 24-48 hours (NLRT2 ) and 5-7 days (NLRT3 ) was significantly higher in patients who died within 30 days (P < 0.05), but not in patients surviving for >30 days. In the multivariate analysis, the 30-day mortality was associated with both NLRT2 (OR 1.112, 95%CI 1.032-1.199, P = 0.006) and NLRT3 (OR 1.163, 95%CI 1.067-1.268, P = 0.001). Spearman correlation analysis showed that both NLRT2 and NLRT3 correlated inversely with GCS score and positively with ICH score and ICH volume at the baseline. CONCLUSIONS: Early rise of NLR predicts 30-day mortality in patients with spontaneous ICH.

Neutrophil-to-Lymphocyte Ratio Is an Independent Predictor of 30-Day Mortality of Intracerebral Hemorrhage Patients: a Validation Cohort Study.

In a previous study in patients with intracranial hemorrhage (ICH), we found an association between high neutrophil-to-lymphocyte ratio (NLR) with poor short-term mortality. In the current study, this preliminary finding was validated using an independent patient cohort. A total of 181 ICH patients (from January 2016 to December 2017) were included. Diagnosis was confirmed using computed tomography (CT) in all cases. Patient survival (up to 30 days) was compared between subjects with high NLR (above the 7.35 cutoff; n = 74) versus low NLR (≤ 7.35; n = 107) using Kaplan-Meier analysis. A multivariate logistic regression was performed to identify factors that influenced the 30-day mortality. Correlation between NLR with other relevant factors (e.g., C-reactive protein (CRP) and fibrinogen) was examined using Spearman correlation analysis. The 30-day mortality was 19.3% (35/181) in the entire sample, 37.8% (28/74) in the high-NLR group, and 6.5% (7/107) in the low-NLR group (P < 0.001). In comparison to the low-NLR group, the high-NLR group had higher rate of intraventricular hemorrhage (29.7 vs. 16.8%), ICH volume (median 23.9 vs. 6.0 cm3) and ICH score (median 1.5 vs. 0), and lower GCS score (9.4 ± 4.5 vs. 12.9 ± 3.2). An analysis that divided the samples into three equal parts based on NLR also showed increasing 30-day mortality with incremental NLR (1.6, 15.0, and 41.7% from lowest to highest NLR tertile, P for trend < 0.001). Kaplan-Meier curve showed higher 30-day mortality in subjects with high NLR than those with low NLR (P < 0.001 vs. low-NLR group, log-rank test). High NLR (> 7.35) is associated with poor short-term survival in acute ICH patients.

Proliferating fibroblasts and HeLa cells co-cultured in vitro reciprocally influence growth patterns, protein expression, chromatin features and cell survival.

AIM: to identify biological interactions between proliferating fibroblasts and HeLa cells in vitro. MATERIALS AND METHODS: Fibroblasts were isolated from both normal and tumour human tissues. Coverslip co-cultures of HeLa and fibroblasts in various ratios with medium replacement every 48 h were studied using fixed cell staining with dyes such as Giemsa and silver staining, with immunochemistry for Ki-67 and E-cadherin, with dihydrofolate reductase (DHFR) enzyme reaction, as well as live cell staining for non-specific esterases and lipids. Other techniques included carmine cell labeling, autoradiography and apoptosis assessment. RESULTS: Under conditions of feeding and cell: cell ratios allowing parallel growth of human fibroblasts and HeLa cells, co-cultured for up to 20 days, a series of phenomena occur consecutively: profound affinity between the two cell types and exchange of small molecules; encircling of the HeLa colonies by the fibroblasts and enhanced growth of both cell types at their contact areas; expression of carbonic anhydrase in both cell types and high expression of non-specific esterases and cytoplasmic argyrophilia in the surrounding fibroblasts; intense production and secretion of lipid droplets by the surrounding fibroblasts; development of a complex net of argyrophilic projections of the fibroblasts; E-cadherin expression in the HeLa cells; from the 10th day onwards, an increasing detachment of batches of HeLa cells at the peripheries of colonies and appearance of areas with many multi-nucleated and apoptotic HeLa cells, and small HeLa fragments; from the 17th day, appearance of fibroblasts blocked at the G2-M phase. Co-cultures at approximately 17-20 days display a cell-cell fight with foci of (a) sparse growth of both cell types, (b) overgrowth of the fibroblasts and (c) regrowth of HeLa in small colonies. These results indicate that during their interaction with HeLa cells in vitro, proliferating fibroblasts can be activated against HeLa. This type of activation is not observed if fibroblast proliferation is blocked by contact inhibition of growth at confluency, or by omitting replacement of the nutrient medium. CONCLUSION: The present observations show that: (a) interaction between proliferating fibroblasts and HeLa cells in vitro drastically influences each other's protein expression, growth pattern, chromatin features and survival; (b) these functions depend on the fibroblast/HeLa ratio, cell topology (cell-cell contact and the architectural pattern developed during co-culture) and frequent medium change, as prerequisites for fibroblast proliferation; (c) this co-culture model is useful in the study of the complex processes within the tumour microenvironment, as well as the in vitro reproduction and display of several phenomena conventionally seen in tumour cytological sections, such as desmoplasia, apoptosis, nuclear abnormalities; and (d) overgrown fibroblasts adhering to the boundaries of HeLa colonies produce and secrete lipid droplets.

Semaphorin 4D expression is associated with a poor clinical outcome in cervical cancer patients.

Lymphangiogenesis is thought to be essential for cancer progression, making it an important target in cancer therapy. Lymphangiogenic factors (VEGF-C and VEGF-D) are upregulated in various tumors/cancers, and play an important role in lymphangiogenesis and lymph node metastasis. Similarly, semaphorin 4D (Sema4D) is a potent inducer of angiogenesis, and its overexpression is associated with tumor progression and poor prognosis in a variety of malignancies. However, little is known regarding the functional relationship between Sema4D and VEGF-C/VEGF-D and in the mediation of lymphangiogenesis and lymph node metastasis and clinical outcome. The current study aimed to evaluate the effect of Sema4D expression on outcome in patients with cervical cancer, and to explore the molecular mechanism of Sema4D in tumor progression. We evaluated Sema4D expression, density of lymphatic vessels, and invasion of lymphatic vessels with immunohistochemical methods in 232 human cervical cancers with long-term follow-up. Sema4D expression was correlated with patho-clinical parameters and patients' outcome. A cervical cancer cell line was used to investigate the contribution of sema4D to tumor progression by studying the role of Sema4D in VEGF-C/-D and cell migration using reverse transcription-polymerase chain reaction and Western blotting. We observed that Sema4D expression was higher in metastatic cervical cancer than in nonmetastatic cervical cancer (P<0.001). CD34-positive or D2-40-positive lymphatic vessel density was significantly increased in cases with lymph node metastasis compared with those without lymph node metastasis. The increased Sema4D expression was associated with VEGF-C/-D, the presence of lymphatic invasion, the occurrence of lymph node metastasis, and FIGO stage. We also observed a novel association between Sema4D upregulation and poor prognosis in cervical cancer. In vitro, the Sema4D inhibitory antibody and Sema4D-shRNA suppressed VEGF-C and VEGF-D in the human cervical carcinoma cell lines HeLa, Siha, and Caski cells. Invasiveness assay demonstrated that Sema4D could augment the invasive potential of the tumor cells in the cervical cancer lines and induction of cellular invasiveness by Sema4D stimulation could be inhibited by knockdown of plexinB1 by siRNA. Further mechanistic investigations of tumor cell invasiveness showed that Sema4D could induce activation of GTPase Ras homolog gene family, member A (RhoA), MAPK and AKT. In addition, plexinB1 knockdown by siRNA could suppress the Sema4D signal transmitted to MAPK and Akt. Taken together, these results suggest that Sema4D autocrine within tumor cells contributes to enhanced invasion and tumor progression through increased motility of cervical cancer and VEGF-C/-D-mediated lymphangiogenesis. Sema4D might be useful as a molecular marker of poor prognosis in cervical cancer.

Effects of 6 months exercise training on ventricular remodelling and autonomic tone in patients with acute myocardial infarction and percutaneous coronary intervention.

OBJECTIVE: To study the effects of 6 months exercise training on ventricular remodelling and autonomic tone in patients with acute myocardial infarction and percutaneous coronary intervention. DESIGN: Single-blinded randomized control trial. PARTICIPANTS: Sixty patients with acute myocardial infarction who had undergone percutaneous coronary intervention. METHODS: The exercise group followed a 6-month supervised exercise programme, while the control group received routine recommendations. All patients underwent an incremental cardiopulmonary exercise test and Doppler echocardiography at baseline and after 6 months. RESULTS: Three patients in the exercise group did not complete the programme. At 6 months follow-up, an improvement was seen in the exercise group compared with the control group regarding peak VO2 (p<0.01), Powermax (p<0.05), VO2 at anaerobic threshold (p<0.01), time to reach anaerobic threshold (p<0.05), heart rate recovery (p<0.01), left ventricular end-diastolic diameter (p<0.01) and left ventricular ejection fraction (p<0.05). CONCLUSION: Six months exercise training in patients with acute myocardial infarction and percutaneous coronary intervention with mild ventricular systolic dysfunction could prevent ventricular remodelling to a certain extent, and favourable modulating sympatho-vagal balance may be an important mechanism.