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1.
Genet Mol Biol ; 43(2): e20190229, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32614356

RESUMEN

Klotho is originally discovered as an anti-aging gene and knock-out of klotho accelerates aging in mice. Subsequent studies support the anti-carcinogenesis role of klotho in a variety of human malignancies. The present study investigated the role of klotho on growth and metastasis of osteosarcoma cells. The osteosarcoma cells were transduced with lentivirus particles encoding klotho or scramble control. The reconstructed osteosarcoma cells were injected into the femoral medullary cavity of nude mice to establish a xenograft animal model. The anti-tumor properties of klotho were evaluated in terms of tumor growth, apoptosis, glycogen production, and pulmonary metastasis. Lentivirus-mediated overexpression of klotho significantly decreased tumor volume and weight in osteosarcoma mice. Determination of PCNA and Ki67 expression revealed that overexpression of klotho inhibited cell proliferation in tumor tissues obtained from osteosarcoma xenografts. PAS staining also showed that overexpression of klotho significantly decreased the production of glycogen in osteosarcoma. Moreover, TUNEL positive cells were significantly increased after lentivirus-mediated overexpression of klotho. Furthermore, lentivirus-mediated upregulation of klotho reduced the number of pulmonary metastatic lesions in mice compared to control mice. These findings demonstrated that elevated klotho could inhibit osteosarcoma cell growth and pulmonary metastasis in vivo, suggesting that klotho may be a valuable therapeutic target for osteosarcoma.

2.
J Chromatogr Sci ; 58(7): 651-660, 2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32627829

RESUMEN

In recent years, a great deal of attention has been paid to the combined use of multiple antitumor drugs for better cancer treatment. The aims of the study are to construct a nanoparticle drug delivery system for the co-delivery of irinotecan hydrochloride and curcumin and to develop an analytical method for simultaneously quantifying these molecules, which is essential for further studies of the co-delivered nano system. The irinotecan hydrochloride and curcumin co-delivered nanoparticle (ICN) were prepared by combinatorially entrapping them into polyethylene glycol-poly lactic acid-co-glycolic acid (PEG-PLGA) polymeric nanoparticles. A simple, sensitive and rapid high-performance liquid chromatography method was developed and validated to simultaneously quantify the compounds in the co-delivered nanoparticle system. Acetonitrile and ultrapure water containing sodium dodecyl sulfate (0.08 mol/L), disodium phosphate (Na2HPO4, 0.002 mol/L) and acetic acid (4%, v/v) were used as the mobile phase and their ratio was set at 50:50. The flow rate was set to 1.0 mL/min, and the temperature in the column oven was maintained at 40°C. The analysis was carried out at 256 and 424 nm to assess irinotecan hydrochloride and curcumin, respectively. Detectors with only one channel can also visualize both analytes in one chromatogram at 379 nm and still demonstrate acceptable sensitivity. The retention times for irinotecan hydrochloride and curium were 3.317 and 5.560 min, respectively. The method developed was confirmed to be sensitive, accurate (recovery, 100 ± 2%), precise (relative standard deviation, RSD ≤ 1%), robust and linear (R2 ≥ 0.9996) in the range from 2.05 to 1050 µg/mL. The presented method has been used to quantify irinotecan hydrochloride and curcumin in the co-delivered ICN nano system to assess the drug delivery quality of the nanoparticles and can also be used for routine analysis because of its simplicity and accuracy.

3.
Sci Rep ; 10(1): 6771, 2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32317711

RESUMEN

Mesenchymal stem cell-based therapy is a highly attractive strategy that promotes bone tissue regeneration. The aim of the present study was to evaluate the combination effect of muscle-derived mesenchymal stem cells (M-MSCs) and platelet-rich plasma (PRP) on bone repair capacity in rabbits with large humeral bone defect. Precise cylindrical bone defects of 10 mm diameter and 5 mm depth were established in rabbit humeral bones, which were unable to be repaired under natural conditions. The rabbits received treatment with M-MSCs/PRP gel, M-MSCs gel, or PRP gel, or no treatment. The bone tissue regeneration was evaluated at day 0-90 after surgery by HE morphological staining, Lane-Sandhu histopathological scoring, tetracycline detection, Gomori staining and micro-computed tomography. Beyond that, Transwell assay, CCK8 assay, Western blot analysis and ALP activity detection were performed in M-MSCs in vitro with or without PRP application to detect the molecular effects of PRP on M-MSCs. We found that the repair effect of M-MSCs group or PRP group was limited and the bone defects were not completely closed at post-operation 90 d. In contrast, M-MSCs/PRP group received obvious filling in the bone defects with a Lane-Sandhu evaluation score of 9. Tetracycline-labeled new bone area in M-MSCs/PRP group and new mineralized bone area were significantly larger than that in other groups. Micro-computed tomography result of M-MSCs/PRP group displayed complete recovery of humeral bone at post-operation 90 d. Further in vitro experiment revealed that PRP significantly induced migration, enhanced the growth, and promoted the expression of Cbfa-1 and Coll I in M-MSCs. In conclusion, PRP application significantly enhanced the regeneration capacity of M-MSCs in large bone defect via promoting the migration and proliferation of M-MSCs, and also inducing the osteogenic differentiation.

4.
JAMA Pediatr ; 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31961395

RESUMEN

Importance: The increasing use rates of electronic cigarettes (e-cigarettes) among young people in the United States have been largely associated with the emergence of high-nicotine-delivery device JUUL. Relevant data are needed to monitor e-cigarette, specifically JUUL, use to help inform intervention efforts. Objective: To estimate the prevalence, patterns, and factors associated over time with e-cigarette use among adolescents and younger adults in the United States. Design, Setting, and Participants: Two nationally representative longitudinal samples of adolescents and younger adults aged 15 to 34 years were drawn from the Truth Longitudinal Cohort, a national, probability-based cohort. Participants in this cohort were recruited through address-based sampling, and subsamples were recruited from a probability-based online panel. The present cohort study used data from follow-up online surveys, specifically, wave 7 (N = 14 379; collected from February 15, 2018, to May 25, 2018) and wave 8 (N = 12 114; collected from February 10, 2019, to May 17, 2019). Respondents reported their use of e-cigarettes, JUUL, and combustible tobacco products as well as their harm perceptions, household smoking status, sensation-seeking, friends' e-cigarette use, and demographic information. Main Outcomes and Measures: The main outcomes were ever and current (past 30 days) JUUL use. χ2 Analyses assessed differences in JUUL use by psychosocial and demographic characteristics. Logistic regression models identified the significant factors associated with wave 8 ever and current JUUL use among wave 7 e-cigarette-naive participants. Results: A total of 14 379 participants (mean [SD] age, 24.3 [0.09] years; 8142 female [51.0%]) were included in wave 7 and 12 114 (mean [SD] age, 24.5 [0.10] years; 6835 female [50.1%]) in wave 8. JUUL use statistically significantly increased from wave 7 to wave 8 among ever users (6.0% [n = 1105] to 13.5% [2111]; P < .001) and current users (3.3% [680] to 6.1% [993]; P < .001). JUUL use increased among every age group and was highest among those aged 18 to 20 years (23.9% [491] ever users and 12.8% [340] current users) and 21 to 24 years (18.1% [360] ever users and 8.2% [207] current users). Users reported a higher prevalence of frequent use in wave 8 compared with wave 7 (37.6% vs 26.1%; P < .01). Significant factors associated with future JUUL use among e-cigarette-naive participants included younger age, combustible tobacco use, lower harm perceptions, sensation seeking, and friends' e-cigarette use. Conclusions and Relevance: This study found that the e-cigarette device JUUL appears to be associated with the youth e-cigarette epidemic, attracting new users and facilitating frequent use with their highly addictive nicotine content and appealing flavors. Findings of this study underscore the critical need for increased e-cigarette product regulation at the federal, state, and local levels.

5.
Biomaterials ; 232: 119701, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31901505

RESUMEN

Various design and fabrication strategies of carrier-based drug delivery systems have been quickly established and applied for cancer therapy in recent years. These systems contribute greatly to current cancer treatments but further development needs to be made to eliminate obstacles such as low drug loading capacity and severe side effects. To achieve better drug delivery, we propose an innovative strategy for the construction of easy manufactured drug self-delivery systems based on molecular structures, which can be used for the co-delivery of curcuminoids and all the nitrogen-containing derivatives of camptothecin for better targeted cancer therapy with minimized side effects. The formation mechanism investigation demonstrates that the rigid planar structures of camptothecin derivatives and curcuminoids with relevant leaving hydrogens make it possible for them to be assembled into nanoparticles under suitable conditions. These nanoparticles show stabilized particle sizes (100 nm) under various conditions and tunable surface charges which increase from around -10 mV in a normal physiological condition (pH 7.4) to +40 mV under acidic tumor environments. In addition, in vivo mice experiments have demonstrated that, compared to irinotecan (a derivative of camptothecin) itself, the co-delivered irinotecan curcumin nanoparticles exhibited significantly enhanced lung and gallbladder targeting, improved macrophage-clearance escape and ameliorated colorectal cancer treatment with an eradication of life-threatening diarrhea, bringing hope for better targeted chemotherapy and clinical translation. Lastly, the strategy of structure based design of drug self-delivery systems may inspire more research and discoveries of similar self-delivered nano systems for wider pharmaceutical applications.

6.
EFORT Open Rev ; 4(8): 513-518, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31538001

RESUMEN

With advances in the treatment of femoral shaft nonunion after intramedullary nailing, the optimal option remains controversial. This study aimed to quantitatively investigate outcomes in a comparison of exchange nailing and augmentative plating for femoral shaft nonunion after intramedullary nailing.The EMBASE, PubMed, Cochrane library and Clinical databases were systematically searched dating from their inception to March 2018. All retrospective controlled and prospective trials evaluating exchange nailing and augmentative plating for the treatment of femoral shaft nonunion after intramedullary nailing were identified. Two investigators extracted all related data independently and we used the review manager software to perform the meta-analysis.Three studies with a total of 232 patients were eligible for data extraction in our study. The meta-analysis indicated that the augmentative plating group had a lower nonunion rate, shorter time to union, less intra-operative blood loss, and shorter operative time than the exchange nailing group. While for the infection rate, there was no significant difference between augmentative plating and exchange nailing group.The available evidence has shown that augmentative plating is superior to exchange nailing for femoral shaft nonunion after intramedullary nailing. Cite this article: EFORT Open Rev 2019;4:513-518. DOI: 10.1302/2058-5241.4.180054.

7.
Prev Med ; 129: 105845, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31518628

RESUMEN

Young adults have the highest prevalence of misuse of prescription opioids. In 2016, 7.1% of 18- to 25-year-olds reported misuse, meaning use other than as prescribed. While smoking is known to be associated with opioid use, to our knowledge no study has examined the relationships between smoking, prescribed use of opioids, and opioid misuse in young adults at the population level. Online survey data were collected in spring 2018 from a nationally representative sample of 18-25-year-olds from the Truth Longitudinal Cohort (N = 10,502). Respondents self-reported cigarette smoking, and both lifetime and recent (past 6-month) prescribed use and misuse of opioids. Generalized ordered logistic regression modeling was used to determine associations between cigarette smoking and recent prescribed use and misuse while controlling for demographic characteristics, other substance use, sensation seeking, and mental health status. Overall, 61.0% of respondents reported lifetime prescribed use of opioids and 16% reported recent prescribed use. Lifetime misuse was reported by 19.4%, with 7.8% reporting recent misuse. Together, the models revealed a graded relationship, with current smokers having higher odds of both prescribed use and misuse, never smokers having lowest odds of use or misuse, and ever smokers, those who had smoked but not in the past 30 days, falling between current and never smokers. Findings indicate a clear association between smoking and use of opioids even after accounting for a strong association between prescribed use and misuse among young adults.

8.
J Insect Physiol ; 119: 103951, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31563619

RESUMEN

Intermittent food shortages are commonly encountered in the wild. To cope with the threat of starvation, insects initiate a suite of behavioral activities and physiological countermeasures. The cotton bollworm, Helicoverpa armigera, is a major agricultural pest worldwide, but how H. armigera modulates its metabolism under starvation remains ambiguous. In the present study, the respiratory rates (V̇O2; ml g-1 h-1) from the third-larval instar to the pupal stage were first determined. Our results highlighted a transient rise during the larval-larval molt and larval-pupal transition, followed by a sharp decline in the pupal stage and, finally, an upward trend before eclosion. When subjected to food deprivation, the starved larvae experienced a significant decline in the rates of O2 consumed and CO2 produced, as well as in respiratory quotient (RQ) values, indicative of severe metabolic depression during starvation and a shift of metabolic substrates with prolonged starvation. For metabolic substrate analysis, an apparent decline in triglyceride and glycogen contents was observed in the starved larvae, and the hemolymph trehalose content was significantly reduced throughout starvation. In addition, comparative transcriptome analysis showed that 48 h of larval starvation caused substantial transcriptional regulations in several energetically costly processes, wherein the marked up-regulations were detected in the pathways of glycolysis and fatty acid metabolism. Overall, our work makes a comprehensive study on the respiratory rate and energy metabolism in the starved H. armigera larvae, and provides a deep insight into the physiological adaptive strategies to alleviate nutritional stress.


Asunto(s)
Metabolismo Energético , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/metabolismo , Inanición/metabolismo , Animales , Dióxido de Carbono/metabolismo , Larva/crecimiento & desarrollo , Larva/metabolismo , Metamorfosis Biológica/fisiología , Muda/fisiología , Consumo de Oxígeno , Pupa/crecimiento & desarrollo , Pupa/metabolismo , Transcriptoma
9.
Cell Mol Biol Lett ; 24: 51, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31410089

RESUMEN

Background: MicroRNAs (miRNAs or miRs) serve crucial roles in the progression of osteoporosis. This study investigated the role and specific molecular mechanism of miR-135-5p in regulating osteoblast differentiation and calcification. Methods: Bone morphogenetic protein 2 (BMP2) was employed to interfere with the differentiation of MC3T3-E1. Then, miR-135-5p mimic or miR-135-5p inhibitor was transfected into MC3T3-E1, and quantitative RT-PCR was used to measure the expression of miR-135-5p. The expressions of runt-related transcription factor 2 (Runx2), osterix (OSX), osteopontin (OPN), and osteocalcin (OCN) were determined using western blot. Alkaline phosphatase (ALP) activity was measured using an appropriate kit assay. Calcium nodule staining was evaluated with alizarin red staining. A luciferase reporter assay was used to verify the target of miR-135-5p. Hypoxia-inducible factor 1 α inhibitor (HIF1AN) overexpression was applied to investigate its own role in the mechanism and a miR-135-5p rescue experiment was also performed. Results: Overexpression of miR-135-5p promoted osteogenic differentiation and calcification, as shown by the increase in ALP activity, calcification and osteogenic marker levels, including Runx2, OSX, OPN and OCN. Knockdown of miR-135-5p yielded the opposite results. HIF1AN was confirmed as a direct target of miR-135-5p. HIF1AN overexpression inhibited osteogenic differentiation and calcification while miR-135-5p reversed these effects. Conclusions: These results indicate that miR-135-5p might have a therapeutic application related to its promotion of bone formation through the targeting of HIF1AN.


Asunto(s)
MicroARNs/genética , Oxigenasas de Función Mixta/genética , Osteoblastos/citología , Osteogénesis , Animales , Diferenciación Celular , Línea Celular , Regulación del Desarrollo de la Expresión Génica , Ratones , Osteoblastos/metabolismo , Regulación hacia Arriba
10.
Exp Ther Med ; 18(3): 1715-1722, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31410129

RESUMEN

The second most common complication following total hip arthroplasty (THA) is dislocation. The majority of dislocations occur early in the post-operative period and are due to either patient-associated or surgical factors. The patient-associated factors that have been implicated as causes of post-operative dislocation include previous surgery, lumbar spine fusion surgery and/or neurological impairment. The surgical factors include surgical approach, component orientation and prosthetic and/or bony impingement. In order to delineate the cause of the hip instability a thorough history and physical and a radiographic assessment (possibly including advanced imaging) needs to be performed. Approximately two thirds of cases are successfully treated; one third of cases will require surgical treatment (e.g., revision arthroplasty (including constrained liners, the use of elevated rim liners and dual mobility implants or trochanteric advancement). In this review, we discuss the causes leading to dislocation following THA and evaluate the different treatment options available.

11.
Drug Alcohol Depend ; 203: 1-7, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31386973

RESUMEN

INTRODUCTION: Considerable declines in cigarette smoking have occurred in the U.S. over the past half century. Yet emerging tobacco products, including e-cigarettes, have increased in popularity among U.S. youth and adults in recent years. Nicotine content is an important factor in weighing the potential benefits and risks of e-cigarettes on individual and population level health. This study examined how nicotine concentrations of e-cigarette products sold have changed from 2013 to 2018. METHODS: E-cigarette sales data aggregated in 4-week periods from March 2, 2013 to September 8, 2018 (66 months total) from convenience store and mass market channels were obtained from Nielsen. Internet and vape shop sales were not available. Internet searches were used to supplement information for nicotine concentration and flavor. Products were categorized by nicotine concentration, flavor, type (disposable or rechargeable), and brand. Dollar sales, unit sales, and average nicotine concentration were assessed. RESULTS: During 2013-2018, the average nicotine concentration in e-cigarettes sold increased overall, for all flavor categories, and for rechargeable e-cigarettes. The proportion of total dollar sales comprised of higher nicotine concentration e-cigarettes (>4% mg/mL) increased from 12.3% to 74.7% during 2013-2018, with a similar increase in unit share. Zero-nicotine products accounted for less than 1% of dollar market share across all years analyzed. CONCLUSIONS: E-cigarettes with higher nicotine concentrations comprise a substantial and increasing portion of U.S. e-cigarette sales. Higher nicotine concentrations may influence patterns of e-cigarette use, including harms from e-cigarette initiation among youth and potential health benefits for adult smokers switching completely to e-cigarettes.


Asunto(s)
Comercio/estadística & datos numéricos , Sistemas Electrónicos de Liberación de Nicotina/economía , Nicotina/análisis , Aromatizantes , Humanos , Productos de Tabaco/análisis , Productos de Tabaco/economía , Estados Unidos
12.
ACS Omega ; 4(5): 9120-9128, 2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31460000

RESUMEN

In the paper, graphene oxide (GO) and two kinds of styrenic resins, poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) and maleic anhydride (MA) grafted SEBS (MA-g-SEBS), were utilized to explore the interfacial interaction of carbon-based materials and block copolymers as layer-by-layer (LBL) assembly films. The details of the interlayer interaction of the two kinds of composite films were investigated through the analysis of the mechanical properties and internal structure of the composites. For the SEBS/GO composite film, the "interlock" structure tended to form between the GO sheets and SEBS resin, and the physical "interlocking effect" could make full use of the excellent mechanical properties of GO nanosheets. As a result, both failure strength and elongation at break of the SEBS/GO composite film were enhanced by 50 and 25%, respectively. On the other hand, some different structures were found in the MA-g-SEBS/GO composite film, where the GO sheets stacked onto the resin closely because of the chemical interaction between them and no obvious "interlocks" was found within the interface, and the chemical interface interaction was strong enough to prevent the slide of GO nanosheets under tension after the graphene sheets were highly oxidized, so the mechanical properties of the MA-g-SEBS/GO composite film could be also enhanced. Based on an overall consideration of the research results of these LBL assembled composites, choosing more perfect materials and structures is needed, which should use physical and chemical interfacial interactions more efficiently, to obtain better mechanical properties of inorganic carbon-organic resin composites.

13.
Artif Cells Nanomed Biotechnol ; 47(1): 2298-2305, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31174440

RESUMEN

Photothermal therapy (PTT) is a rapidly developing approach for cancer therapy, which has been widely recognized to exert high efficacy as compared to chemotherapy. However, the limited tumour homing property of currently available drug delivery systems (DDSs) is the bottleneck for the efficient delivery of photothermal agents. Here in this study, we surface modified silica nanoparticles (SLN) with the cell membrane (CM) derived from 143B cells to construct a platform (CM/SLN) capable of targeting the homogenous 143B cells. In addition, indocyanine green (ICG) as a photothermal agent was encapsulated into CM/SLN to finally construct a DDS suitable for tumour-targeted PTT of osteosarcoma. Our results revealed that CM/SLN/ICG was mono-dispersed core-shell nanoparticles with advanced stability in a physiological environment. Moreover, due to the modification of CM, CM/SLN/ICG could specifically target the homogenous 143B cells both in vitro and in vivo, which demonstrated superior anticancer efficacy when compared with either SLN/ICG or free ICG. Hence, CM/SLN/ICG could be a promising DDS for tumour targeted PTT of osteosarcoma.


Asunto(s)
Membrana Celular/metabolismo , Portadores de Fármacos/química , Verde de Indocianina/química , Nanopartículas/química , Osteosarcoma/tratamiento farmacológico , Fotoquimioterapia , Dióxido de Silicio/química , Animales , Transporte Biológico , Línea Celular Tumoral , Portadores de Fármacos/metabolismo , Femenino , Humanos , Verde de Indocianina/uso terapéutico , Ratones , Ratones Endogámicos BALB C , Osteosarcoma/patología
14.
J Econ Entomol ; 112(3): 1411-1417, 2019 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-30789202

RESUMEN

Juvenile hormone (JH) regulates many physiological processes in insect development, diapause, and reproduction. Juvenile hormone binding protein (JHBP), the carrier partner protein of JH, is essential for the balance of JH titer to regulate the metamorphosis and development of insect. In this study, two JHBP genes were identified from Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), namely HaJHBP1 and HaJHBP2. The tissue and temporal expression pattern revealed that both HaJHBP1 and HaJHBP2 were dominantly expressed in larval fat body, and their high transcription stages were detected in fourth and fifth instars. The ingestion of methoprene, a JH analogue, significantly induced the expression of HaJHBP1 and HaJHBP2. However, both HaJHBP1 and HaJHBP2 mRNA levels were significantly downregulated after treated with a JH antagonist, precocene. When subject to starvation, larvae showed a marked suppressive effect in the expression of HaJHBP1 and HaJHBP2. These results indicate that JHBP plays a part in the JH-regulated metabolism, growth, or development in reaction to different nutritional conditions.


Asunto(s)
Mariposas Nocturnas , Animales , Proteínas de Insectos , Hormonas Juveniles , Larva , Metamorfosis Biológica , Metopreno
15.
Nicotine Tob Res ; 21(4): 458-468, 2019 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-29452385

RESUMEN

INTRODUCTION: Among youth, the frequency and prevalence of using more than one tobacco (small cigar, cigarette, and hookah) or nicotine-containing product (e-cigarettes-ENDS) are changing. These shifts pose challenges for regulation, intervention, and prevention campaigns because of scant longitudinal data on the stability of use patterns in this changing product landscape. METHODS: A nationally representative longitudinal survey of 15- to 21-year olds (n = 15,275) was used to describe transitions between never use, noncurrent use, and past 30-day use of combustible tobacco, e-cigarettes (ENDS), and dual use of both kinds of products. A multistate model was fit to observations collected every 6 months across 2.5 years to estimate the probability of transitions between states (TPs), the average time in state (sojourn time), and the effect of age on transitions. RESULTS: Current state strongly predicted future state over time intervals of 1 year or less, but only weakly predicted future state at longer intervals: TP to noncurrent use was higher for ENDS-only than combustible-only users over a 6-month interval but was similar for both groups over a 2-year interval. Sojourn time was significantly longer for combustible-only (0.52 years) and dual use (0.55 years) than ENDS-only use (0.27 years); older youth were more likely than younger youth to stay combustible tobacco users or noncurrent users. CONCLUSIONS: The dynamics of transitions between combustible tobacco products and ENDS in a population of youth and young adults suggest that policy and prevention efforts must consider the frequent changes and instability over a 1-year or less time period in use patterns among young people. IMPLICATIONS: The study addresses an urgent need in public health for timely information on how youth and young adults use tobacco and nicotine products. We found that youth, particularly adolescents, moved frequently between using ENDS and combustible tobacco products either alone or together. Importantly, the utility of current-use states for predicting future use states declined for time horizons longer than 1 year. Our results demonstrate a need for caution in interpreting product transitions. Longitudinal data with frequent observations and coverage of a wide range of possible product types is required to fully characterize usage patterns in youth.


Asunto(s)
Uso de Tabaco/epidemiología , Uso de Tabaco/tendencias , Adolescente , Factores de Edad , Sistemas Electrónicos de Liberación de Nicotina , Femenino , Humanos , Estudios Longitudinales , Masculino , Prevalencia , Pipas de Agua , Productos de Tabaco , Uso de Tabaco/psicología , Adulto Joven
16.
Tob Control ; 28(6): 603-609, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30377241

RESUMEN

OBJECTIVE: To estimate the prevalence of JUUL use and identify demographic and psychosocial correlates of use among youth and young adults in the USA. METHODS: A national, probability-based sample was recruited via address-based sampling, with subsamples recruited from an existing probability-based online panel. Participants (N=14 379) ages 15-34 were surveyed about JUUL use, tobacco use, electronic nicotine delivery system (ENDS) harm perceptions, sensation seeking and demographic characteristics. Data were collected February-May 2018. Χ2 analyses assessed differences in JUUL use by demographic and psychosocial characteristics. Logistic regressions identified significant correlates of ever and current JUUL use. RESULTS: Overall, 6.0% reported ever JUUL use, and 3.3% reported past 30-day (ie, current) use. Rates were higher among participants aged 15-17 and 18-21 years, with 9.5% and 11.2% reporting ever use, and 6.1% and 7.7% reporting current use, respectively. Among current users aged 15-17 years, 55.8% reported use on 3 or more days in the past month, and over a quarter reported use on 10-30 days. Significant correlates of use included younger age, white race, greater financial comfort, perceptions of ENDS as less harmful than cigarettes, household ENDS use, high sensation seeking and current combustible tobacco use. CONCLUSION: JUUL use was significantly higher among young people, with those under 21 having significantly higher odds of ever and current use. Frequency of use patterns suggest youth may not be experimenting with the device but using it regularly. Given the high nicotine content of JUUL, there is concern over the potential for addiction and other serious health consequences among young people. Findings suggest strong regulatory actions are needed to prevent youth and young adult uptake.

17.
Connect Tissue Res ; 60(3): 304-310, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30288996

RESUMEN

PURPOSE: To investigate the pathogenesis and find a better prophylactic method of acquired heterotopic ossification (HO). MATERIALS AND METHODS: In the first part, we designed the brain-traumatic/burn/tenotomy rat model and testified its efficacy as HO model. 44 rats were randomly divided into experimental group and control group. After operation, the bilateral tendons of 2 rats were collected at the 2nd, 3rd, 4th, 6th, 8th, and 10th weeks to determine the expression levels of p65. Additionally, the remaining rats were exposed to X-Ray examination at the 10th week. In the second part, 124 rats were randomly divided into four groups based on the administration dosage of Ammonium pyrrolidinedithiocarbamate (PDTC). Then, three rats of each group were euthanized every week in the first seven weeks to collect tendon to detect the expression levels of p65 by qRT-PCR and Western Blot. The remaining rats were exposed to X-Ray examination at the 10th week to assess the size of HO before being euthanized for HE staining. RESULTS: The success rate of Brain-traumatic/Burn/Tenotomy model was 100%. Pharmacologic inhibition of Nf-ҝb signaling pathway by PDTC could significantly reduce the expression levels of p53 and the size of HO, and the reduction was most significant in the 0.6mg dosage group. CONCLUSIONS: Brain-traumatic/Burn/Tenotomy model was highly reliable HO model. Inhibition of Nf-ҝb signaling pathway by PDTC could significantly reduce HO formation, and the most effective concentration was 6 mg/ml for local injection.

18.
J Public Health Res ; 7(2): 1379, 2018 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-30581807

RESUMEN

Campaign costs are rising, making ad execution testing more critical to determine effectiveness prior to media spending. Premarket testing occurs prior to messages' airing while in-market testing examines message attributes when messages are aired within a real-world setting, where context plays an important role in determining audience response. These types of ad testing provide critical feedback to help develop and deploy campaigns. Due to recent changes in media delivery platforms and audience tobacco use behavior, this study analyzes two nationally representative youth samples, aged 15-21, to examine if pre-market ad testing is an indicator of in-market ad performance for public health campaigns, which rely on persuasive messages to promote or reduce health behaviors rather than selling a product. Using data from the Truth® campaign, a national tobacco use prevention campaign targeted to youth and young adults, findings indicate strong associations between pre-market scores and in-market ad performance metrics.

19.
Front Physiol ; 9: 1601, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30498452

RESUMEN

Juvenile hormone (JH) represses larval metamorphosis and induces adult reproduction in insects. Methoprene-tolerant (Met) is identified as an intranuclear receptor that mediates JH actions. In the present study, we characterized a Met from the severe agricultural pest, Helicoverpa armigera, namely HaMet. In the larval stage, HaMet is predominantly expressed in the epidermis and midgut, and is upregulated before each molting, whereas in adults HaMet is maximally expressed in the ovary, testis, and fat body. The immunofluorescence assay revealed that HaMet was distributed in the longitudinal and circular muscle layers of midgut in larvae, whereas in the ovary of female adults, HaMet was localized in the nucleus of the oolemma. Knockdown of HaMet in final-instar larvae shortened the time of pupation, induced abnormal pupation, and dampened pupation rate. In female adults, HaMet depletion severely suppressed the transcription of Vitellogenin (Vg) and Vitellogenin Receptor (VgR), disrupted the Vg accumulation in fat body and the yolk protein uptake in oocytes, and finally led to an impaired fecundity. Our findings therefore confirmed that HaMet acted as a nuclear receptor of JH and played an essential role in larval metamorphosis, vitellogenesis, and oocyte maturation.

20.
PLoS One ; 13(8): e0200827, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30096141

RESUMEN

This study's objective was to describe long-term trends and patterns in first cigarette use (cigarette initiation) and daily cigarette use (daily initiation) among youth and young adults in the U.S. We used cross-sectional survey data from the National Survey on Drug Use and Health, 2002-2015, to estimate annual incidence of first cigarette use (N = 270,556) and first daily cigarette use (N = 373,464) for each year by age groups, race/ethnicity and gender, examining trends over time and the average annual change in initiation for each group. Several clear patterns emerged: 1) cigarette initiation and daily initiation significantly decreased over time among those aged 12-14 and 15-17 and these trends were consistent among nearly all racial/ethnic and gender subgroups; 2) among 18-21 year olds, cigarette initiation sharply increased through 2009, surpassing rates among 15-17 year olds, and sharply declined through 2015 while remaining higher than rates among the younger group, and this trend was consistent for almost all racial/ethnic subgroups; 3) daily initiation for those aged 18-21 significantly declined, and this was significant among most subgroups 4) there was no change in cigarette initiation and daily initiation for 22-25 year olds overall and most subgroups; 5) there was a significant increase in cigarette initiation for 22-25 year old Hispanics males and daily initiation for 22-25 year old males. This study provides a comprehensive look at trends in cigarette and daily initiation among U.S. youth and young adults. Despite notable declines in smoking initiation among youth and young adult populations over the last two decades, targeted prevention and policy efforts are needed for subgroups at higher risk, including young adults and Hispanic males.


Asunto(s)
Fumar Cigarrillos/epidemiología , Adolescente , Adulto , Afroamericanos/estadística & datos numéricos , Factores de Edad , Niño , Fumar Cigarrillos/prevención & control , Fumar Cigarrillos/tendencias , Estudios Transversales , Grupo de Ascendencia Continental Europea/estadística & datos numéricos , Femenino , Encuestas Epidemiológicas/estadística & datos numéricos , Hispanoamericanos/estadística & datos numéricos , Humanos , Masculino , Estados Unidos/epidemiología , Adulto Joven
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