Does smoking cessation increase risk of knee replacement? a general population-based cohort study

OBJECTIVE

Smoking represents a major issue for global public health. Owing to methodologic challenges, findings of an association between smoking and risk of knee osteoarthritis (OA) are inconsistent. We sought to assess the relation of onset of smoking cessation to the risk of OA sequelae, i.e., knee replacement, and to perform sub-cohort analysis according to weight change after smoking cessation.

DESIGN

Using The Health Improvement Network, we conducted a cohort study to examine the association between smoking cessation and risk of knee replacement among patients with knee OA. Participants who stopped smoking were further grouped into three sub-cohorts: weight gain (body mass index [BMI] increased>1.14 kg/m²), no substantial weight change (absolute value of BMI change<1.14 kg/m²), and weight loss (BMI loss>1.14 kg/m²) after smoking cessation.

RESULTS

We identified 108 cases of knee replacement among 1,054 recent quitters (26.7/1,000 person-years) and 1,108 cases among 15,765 current smokers (17.4/1,000 person-years). The rate difference of knee replacement in recent quitter cohort vs current smoker cohort was 10.4 (95% confidence interval [CI]:5.3-15.6)/1,000 person-years and the adjusted hazard ratio (HR) was 1.30 (95%CI:1.05-1.59). Compared with current smokers, risk of knee replacement was higher among quitters with weight gain (HR = 1.42,95%CI:1.01-1.98), but not among those with no substantial weight change (HR = 1.29,95%CI:0.90-1.83) or those with weight loss (HR = 1.11,95%CI:0.71-1.75).

CONCLUSIONS

Our large population-based cohort study provides the first evidence that smoking cessation was associated with a higher risk of knee replacement among individuals with knee OA, and such an association was due to weight gain after smoking cessation.

Circ_0000515 drives the progression of hepatocellular carcinoma by regulating MAPK10

OBJECTIVE

To explore the expression pattern and clinical significance of circ_0000515 in hepatocellular carcinoma (HCC), as well as the molecular mechanism.

PATIENTS AND METHODS

Fifty HCC patients were recruited, and their cancer tissues and adjacent normal ones were collected for detecting the differential expression of circ_0000515. The relationship between circ_0000515 and clinical parameters in HCC patients was analyzed. Circ_0000515 knockdown model was generated by lentivirus transfection in Hep3B and MHCC88H cells that were highly expressed with circ_0000515. Regulatory effects of circ_0000515 on phenotypes of Hep3B and MHCC88H cells were examined by Cell Counting Kit-8 (CCK-8) and transwell assay. Target gene of circ_0000515 was verified by Dual-Luciferase reporter assay, and its involvement in HCC progression was detected by rescue experiments. In vivo xenograft model was generated in nude mice aiming to elucidate the role of circ_0000515 in regulating HCC growth.

RESULTS

Circ_0000515 was highly expressed in HCC tissues and cell lines. High level of circ_0000515 predicted advanced stage, high incidence of lymphatic metastasis, and low disease-free survival and overall survival in HCC. Knockdown of circ_0000515 attenuated proliferative and migratory abilities in Hep3B and MHCC88H cells. MAPK10, as the target gene binding circ_0000515, was negatively regulated by circ_0000515. Rescue experiments and in vivo xenograft model both indicated that circ_0000515 aggravated the malignant progression of HCC by targeting MAPK10.

CONCLUSIONS

Circ_0000515 is upregulated in HCC tissues and cell lines. It can be used for predicting tumor staging, lymphatic metastasis, and prognosis in HCC. Circ_0000515 aggravates the malignant progression of HCC by downregulating MAPK10.

First Simultaneous Acceleration of Multiple Charge States of Heavy Ion Beams in a Large-Scale Superconducting Linear Accelerator

Experimental studies of the simultaneous acceleration of three-charge-state ^{129}Xe^{49+,50+,51+} beam from 17 to 180  MeV/nucleon in a superconducting linear accelerator are presented. The beam parameters for each individual- and multiple-charge-state beam were measured and compared with the particle tracking simulations. Detailed measurements were performed to characterize the multiple-charge-state beam's recombination after a second-order achromat and isopath 180° bending system. As a result of the recombination of three charge states in the six-dimensional phase space, the xenon beam intensity was increased by 2.5-fold compared to the single-charge-state beam. The results presented in the Letter fully validate the possibility to produce and utilize high-quality multiple-charge-state heavy-ion beams in a large-scale superconducting linac to increase the available beam power on an isotope production target.

Properties of Heavy Secondary Fluorine Cosmic Rays: Results from the Alpha Magnetic Spectrometer

Precise knowledge of the charge and rigidity dependence of the secondary cosmic ray fluxes and the secondary-to-primary flux ratios is essential in the understanding of cosmic ray propagation. We report the properties of heavy secondary cosmic ray fluorine F in the rigidity R range 2.15 GV to 2.9 TV based on 0.29 million events collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The fluorine spectrum deviates from a single power law above 200 GV. The heavier secondary-to-primary F/Si flux ratio rigidity dependence is distinctly different from the lighter B/O (or B/C) rigidity dependence. In particular, above 10 GV, the F/Si/B/O ratio can be described by a power law R^{δ} with δ=0.052±0.007. This shows that the propagation properties of heavy cosmic rays, from F to Si, are different from those of light cosmic rays, from He to O, and that the secondary cosmic rays have two classes.

Circ_CHFR expedites cell growth, migration and inflammation in ox-LDL-treated human vascular smooth muscle cells via the miR-214-3p/Wnt3/β-catenin pathway

OBJECTIVE

Atherosclerosis (AS) is a representative inflammatory vascular disease. This study explored the molecular pathogenesis of AS based on circular RNA (circRNA), the checkpoint with forkhead-associated and ring-finger domains (circ_CHFR).

PATIENTS AND METHODS

The cell model of AS in vitro was established by stimulating human vascular smooth muscle cells (VSMCs) with oxidized low-density lipoprotein (ox-LDL). The RNA expression was measured by quantitative Real-time polymerase chain reaction (qRT-PCR). Cell viability and colony formation ability were separately evaluated using 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) and colony formation assay. Cell migration was assessed via the transwell assay. The inflammation injury was analyzed by enzyme-linked immunosorbent assay (ELISA). Associated proteins were determined through Western blot. The combination of hypothetic targets was ascertained using Dual-Luciferase reporter assay.

RESULTS

Circ_CHFR was up-regulated in AS serums and ox-LDL-stimulated VSMCs. Circ_CHFR depletion weakened the ox-LDL-induced promotion of cell growth, migration and inflammation in VSMCs. Circ_CHFR positively regulated Wnt3 expression and the downregulation of Wnt3 abrogated the ox-LDL-triggered injuries in VSMCs. Circ_CHFR functioned as the sponge of microRNA-214-3p (miR-214-3p) and miR-214-3p targeted Wnt3. Circ_CHFR regulated cell growth, migration and inflammation via regulating the expression of Wnt3 as a competitive endogenous RNA (ceRNA) of miR-214 in ox-LDL-treated VSMCs. Circ_CHFR/miR-214-3p axis mediated the Wnt3/β-catenin signal pathway.

CONCLUSIONS

Circ_CHFR contributed to the progression of AS through the miR-214-3p/Wnt3/β-catenin signals, which illuminated the molecular mechanism of AS and suggested circ_CHFR might be an index for AS treatment.

Properties of Iron Primary Cosmic Rays: Results from the Alpha Magnetic Spectrometer

We report the observation of new properties of primary iron (Fe) cosmic rays in the rigidity range 2.65 GV to 3.0 TV with 0.62×10^{6} iron nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. Above 80.5 GV the rigidity dependence of the cosmic ray Fe flux is identical to the rigidity dependence of the primary cosmic ray He, C, and O fluxes, with the Fe/O flux ratio being constant at 0.155±0.006. This shows that unexpectedly Fe and He, C, and O belong to the same class of primary cosmic rays which is different from the primary cosmic rays Ne, Mg, and Si class.

Anaerobic digestion of microalgal biomass for bioenergy production, removal of nutrients and microcystin: current status

Using renewable microalgal biomass as active feedstocks for biofuels and bioproducts is explored to substitute petroleum-based fuels and chemicals. In the last few years, the importance of microalgae biomass has been realized as a renewable feedstock due to several positive attributes associated with it. Biorefinery via anaerobic digestion (AD) of microalgal biomass is a promising and sustainable method to produce value-added chemicals, edible products and biofuels. Microalgal biomass pretreatment is a significant process to enhance methane production by AD. Findings on the AD microbial community's variety and organization can give novel in turn on digester steadiness and presentation. This review presents a vital study of the existing facts on the AD microbial community and AD production. Co-digestion of microalgal biomass with different co-substrates was used in AD to enhance biogas production, and the process was economically viable with improved biodegradability. Microcystins, which are produced by toxic cyanobacterial blooms, create a severe hazard to environmental health. Anaerobic biodegradation is an effective method to degrade the microcystins and convert into nontoxic products. However, for the cost-effective conversion of biomass to energy and other beneficial byproducts, additional highly developed research is still required for large-scale AD of microalgal biomass.

Persistent chest pain at 1-year predicts long-term angina hospitalization in women with and without obstructive coronary artery disease: results from Women's Ischemia Syndrome Evaluation (WISE)

Background

There is growing evidence that women with ischemia and no obstructive coronary artery disease (INOCA) have an increased risk of major adverse cardiovascular events (MACE). Half of these women continue to experience persistent chest pain (PChP); however longer-term outcomes are unknown.

Purpose

To investigate the relationships between PChP at 1-year with obstructive and nonobstructive coronary artery disease (CAD) and longer-term all-cause mortality, MACE and angina hospitalization in women with suspected myocardial ischemia.

Methods

We studied 673 women with chest pain undergoing coronary angiography for suspected myocardial ischemia in the National Heart, Lung, and Blood Institute Women's Ischemia Syndrome Evaluation (WISE) study. PChP was defined as self-reported continuing chest pain at 1-year, obstructive CAD as &gt;50 stenosis in any coronary artery and non-obstructive CAD was further divided as &lt;20% stenosis and 20–50% stenosis in any coronary artery. The Kaplan-Meier method was used to estimate cumulative incidence rates of all-cause mortality, MACE, and angina hospitalization. Proportional hazards regression estimated adjusted hazard ratios of mortality, MACE and angina hospitalization in relation to PChP at 1-year in obstructive and nonobstructive CAD.

Results

The median age was 58 years, 45% had PChP, and 39% had obstructive CAD with a median follow-up time of 9 years (range 1 to 11) for mortality and 5 years (range 0 to 9) for MACE and anginal hospitalization. There was no difference in mortality or MACE in women with PChP compared to women without PChP in any of the 3 groups (&lt;20%, 20–50%, or &gt;50% CAD), however differences were noted in long-term angina hospitalization (Figure 1). Notably,angina hospitalization rates in women with PChP and nonobstructive CAD were 2.2 times those of women without PChP, and comparable to those of women with obstructive CAD and no PChP (p&lt;0.0001).

Conclusions

Among women undergoing coronary angiography for suspected myocardial ischemia, women with nonobstructive CAD and PChP have rates of angina hospitalization comparable to patients with obstructive CAD without PChP. Thus, PChP increases the hazard of long term anginal hospitalization regardless of the presence or absence of obstructive CAD. Given the economic burden of angina hospitalization, further studies are needed to determine whether aggressive treatment in women with PChP without obstructive CAD changes outcomes and impact on the health care system.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health (NIH)

Role of physical fitness in the obesity paradox. Long-term major adverse cardiovascular events in the Women's Ischemia Syndrome Evaluation (WISE)

Background

Emerging data suggests there is an “obesity paradox” where obesity may be protective against cardiovascular morbidity and mortality in patients with cardiovascular disease. However, weight status primarily assessed through body mass index (BMI) is limited in its ability to discern contributions from fat vs. lean muscle mass. Most studies on BMI have not accounted for physical fitness, which is a known modifier of weight status and a potential mediator of effects of obesity on major adverse cardiovascular events (MACE).

Purpose

To investigate the relationship between BMI and physical fitness, measured by self-reported Duke Activity Status Index (DASI) score, with long-term MACE in women evaluated for suspected myocardial ischemia.

Methods

The National Heart, Lung, and Blood Institute Women's Ischemia Syndrome Evaluation (WISE) study is a multicenter prospective cohort study. From 1996–2000, 936 women were enrolled at the time of clinically indicated coronary angiography and assessed with a median follow up of 5.8 (range 0–9 years) for MACE. MACE was defined as a composite of death, nonfatal myocardial infarction, stroke, or congestive heart failure. Proportional hazards regression was used to estimate adjusted hazard ratios of MACE in relation to metabolic status and physical fitness. DASI scores ≥25, equivalent to ≥7 metabolic equivalents [METs]) was used as cut point to define high physical fitness, in our prior studies DASI &gt;25 approximates completion of the second stage of a Bruce treadmill protocol.

Results

Among the 899 women with complete data, 69.5% had low physical fitness (DASI scores &lt;25), 34.9% overweight (BMl ≥25 to 30), 40.5% obese (BMI ≥30). In fit women, obesity was associated with lower hazard ratio for MACE (HR 0.64, p=0.01); while low fitness in normal weight women was associated with 60% excess risk of MACE (HR 1.61, p=0.01) (Figure 1).

Conclusions

Among women undergoing coronary angiography for suspected myocardial ischemia, obesity was inversely related with long-term MACE in physically fit women. Our findings suggest that physical fitness may play a role in the obesity paradox. These results support the inclusion of fitness in understanding the relations between body weight and long-term MACE. The DASI is a simple, self reported tool that can identify higher-risk symptomatic women and should be considered in future investigations and routine examination of normal, overweight and obese women.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): U01 HL064829

The effect of Clostridium tyrobutyricum Spo0A overexpression in the intestine of mice

Clostridium tyrobutyricum shows probiotic properties and can affect the composition of gut microbiota and regulate the intestinal immune system. Compared with other probiotics, this spore-producing bacterium shows unparalleled advantages in commercial production. In addition to being resistant to extreme living environments for extended periods, its endophytic spores are implicated in inhibiting cancer cell growth. We speculated that C. tyrobutyricum spores can also promote gut health, which mean it can maintain intestinal homeostasis. To date, the beneficial effects of C. tyrobutyricum spores on gut health have not been reported. In this study, a Spo0A-overexpressing C. tyrobutyricum strain was developed to increase spore production, and its probiotic effects on the gut were assessed. Compared with the wild-type, the engineered strain showed significantly increased sporulation rates. Mice administered with the engineered strain exhibited enhanced intestinal villi and the villus height/crypt depth ratio, weight gain and improved Firmicutes/Bacteroidetes ratio to facilitate intestinal homeostasis. This study demonstrated for the first time that enhanced spore production in C. tyrobutyricum can improve intestinal homeostasis, which is advantageous for its commercial application in food and pharmaceutical industry.

[Intrauterine balloon tamponade combined with temporary abdominal aortic balloon occlusion in the management of women with placenta accreta spectrum:a randomized controlled trial]

Objective: To access the effectiveness and safety of the intrauterine balloon tamponade verse gauze packing combined with temporary abdominal aortic balloon occlusion in the management of placenta accreta spectrum (PAS). Methods: This was an open-label, randomized controlled trial conducted in Nanjing Drum Tower Hospital. The patients suspected with PAS for uterine preservation surgery under the multidisciplinary team care were recruited between Aug 2015 and Jan 2018. When bleeding could not be achieved after fetus delivered, and a temporary abdominal aortic balloon occlusion and the compression sutures as needed, the women were randomly allocated 1∶1 into balloon tamponade (n=81) or gauze packing (n=80) group. The primary outcome was successful bleeding arrests by avoiding second line surgeries. The secondary outcomes included the volume of blood loss during and after cesarean section, the rate of PPH, incidence and amount of blood transfusion, hysterectomy, postpartum pain, ICU admission, need for re-laparotomy, and the length of hospital stay, readmission, and interventional radiology complications. Results: All the women [100% (81/81)] in the balloon group were obtained hemostasis without further intervention, significantly higher than 88% (70/80) in the gauze group (P=0.001). Before uterine tamponade, blood loss were 820 ml (620-1 230) ml and 850 ml (605-1 442) ml, while placenta bed were sutured in 96%（78/81, 77/80） respectively (P>0.05).The proportion of blood loss≥1 000 ml was higher in the gauze group than that in the balloon group (P=0.006). Maternal adverse events involving total blood loss, puerperal morbidity and postpartum pain occurred more frequently in the gauze group (P<0.05). The following outcome showed no statistically significant difference between the two groups: the vascular occlusion time, the dose of radiation, and interventional radiology complication (P>0.05). The median volume infused into the lower and upper balloons is 70 ml (50-100 ml) and 180 ml (100-240 ml). Conclusions: Incrauterine balloon tamponade is as effective as gauze packing in hemostasis following the placenta delivery in PAS. Compared with gauze packing, the uterine balloon tamponade is more effective.

2D-MoS2/BMN Ceramic Hybrid Structure Flexible TFTs with Tunable Device Properties

Two-dimensional (2D) layered semiconductor materials have emerged as prospective channel materials in flexible thin-film field effect transistors (TFTs) recently because of their unique electrical and mechanical characteristics. Meanwhile, high-quality ceramics, with outstanding dielectric property and fabrication process compatible with low-cost flexible substrates, have become one of the best candidates of gate dielectric layers in flexible TFTs. In this work, 2D MoS₂ and dielectric ceramic Bi₂MgNb₂O₉ (BMN) were utilized to fabricate flexible TFTs on low-cost polyethylene terephthalate substrates. The MoS₂/BMN hybrid structure exhibited good quality by Raman, X-ray photoelectron spectroscopy, and atomic force microscopy characterizations. In addition, the flexible MoS₂/BMN TFTs indicated good performances with a small gate voltage. More importantly, with the modulation of gate voltage, the flexible TFTs surprisingly exhibited three different device types, that is, multilayer MoS₂/BMN n-type TFT (device type 1), homojunction MoS₂/BMN TFT (device type 2), and thick MoS₂/BMN p-type TFT (device type 3). In particular, with different bias conditions, the homojunction TFT showed bipolarity of transfer characteristics and forward/backward rectifications of output characteristics similar to p-n/n-n junctions. The high dielectric constant and high quality of the BMN ceramic layer enabled the gate to effectively modulate these different structures of MoS₂ channels. The operation mechanisms of these three types of flexible TFTs were investigated. Additionally, the flexible MoS₂/BMN TFTs showed good flexibility and performance stability with external strains. The results prove the great potential of integration of 2D materials, high-quality dielectric ceramics, and low-cost plastic substrates for high-performance flexible TFTs and further applications of flexible electronics.

Proton transport enabled by a field-induced metallic state in a semiconductor heterostructure

Tuning a semiconductor to function as a fast proton conductor is an emerging strategy in the rapidly developing field of proton ceramic fuel cells (PCFCs). The key challenge for PCFC researchers is to formulate the proton-conducting electrolyte with conductivity above 0.1 siemens per centimeter at low temperatures (300 to 600°C). Here we present a methodology to design an enhanced proton conductor by means of a Na _x CoO₂/CeO₂ semiconductor heterostructure, in which a field-induced metallic state at the interface accelerates proton transport. We developed a PCFC with an ionic conductivity of 0.30 siemens per centimeter and a power output of 1 watt per square centimeter at 520°C. Through our semiconductor heterostructure approach, our results provide insight into the proton transport mechanism, which may also improve ionic transport in other energy applications.