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Objective: To investigate the prevalence and common sites of severe foot pain among nurses, to define the risk factors of severe foot pain in nurses in tertiary hospital in China, and to construct a nomograph model for predicting individuals' risks for severe foot pain. Methods: Between August 2019 and December 2019, a stratified global sampling method was used to select 10691 nurses from 351 tertiary hospitals in China to investigate the incidence of severe foot pain among them. The variables that may affect the occurrence of severe foot pain were analyzed by single factor analysis to identify the influencing factors of severe foot pain in nurses. Furthermore, the independent risk factors of severe foot pain were analyzed by stepwise logistic regression analysis. The statistically significant factors identified in the multivariate regression analysis were incorporated into the nomograph prediction model. The predictive performance of the nomograph was measured by the consistency index (C-index) and calibrated with 1000 Bootstrap samples. Results: A total of 3419 nurses out of the 10691 had foot pain, resulting in an incidence of 31.98%. The incidence of severe pain (VAS score 7-10) was 2.27% (243 of 10691). The locations of severe pain were more commonly found in the soles and heels of both feet. Six factors, including age, education, the material of the work shoes, comfortableness of the work shoes, number of complications, and foot injure history, were incorporated in the nomograph predicting model. The C-index value was 0.706 and the standard curve fitted well with the calibrated prediction curve. Conclusion: The risk prediction model constructed in this study showed sound performance in predicting the risk of severe foot pain in nurses, and all the indicators involved are simple and the relevant data are easily obtained. The model can provide reference for preventing severe foot pain in nurses.
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Enfermeras y Enfermeros , Dolor , Humanos , Centros de Atención Terciaria , Dolor/epidemiología , China/epidemiologíaRESUMEN
BACKGROUND: Several surveys have reported that patients treated with gonadotropin-releasing hormone antagonist (GnRH-ant) protocol showed a significantly lower rate of implantation and clinical pregnancy compared to GnRH agonist (GnRH-a) protocol during in vitro fertilization-fresh embryo transfer. Subsequent studies imputed this poor outcome to the negative effects of GnRH-ant on endometrial receptive. However, the mechanisms were not fully understood. METHODS: The clinical data of 2815 patients undergoing fresh embryo transfer in our center were analyzed. Human endometrial stromal cells (ESCs) from healthy women undergoing elective pregnancy termination of a normal pregnancy at 8-10 weeks gestation were treated with GnRH-analogs or imatinib (c-kit receptor inhibitor). CCK8 and Flow cytometry were used to investigated the growth ability of ESCs. Immunofluorescence staining and western blot was used to detected the target proteins. RESULTS: The clinical data showed that the endometrial thickness on HCG Day were significantly lower in GnRH-ant group. Although no difference of embryo quality in these two groups, GnRH-ant group showed remarkably decreased rate of HCG positive, embryo implantation and pregnancy. Moreover, GnRH-ant significantly reduced the proliferation and induced the apoptosis of ESCs. Furthermore, the expression and activation of c-kit receptor, which played pivotal roles during embryo implantation, were observably decreased by GnRH-ant. Inhibiting the activation of c-kit by imatinib remarkably suppressed the proliferation and promoted the apoptosis of ESCs. Additionally, the phosphorylation of AKT and expression of Cyclin D1, which were closely related with cellular growth, were distinctly lessened after treating with imatinib. CONCLUSIONS: In summary, our study showed that GnRH-ant weakened the activization of c-kit receptor by decreasing its expression, causing the impaired growth ability of ESCs. Our findings provided a new insight into the effects of GnRH-ant on endometrium.
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Endometrio/efectos de los fármacos , Antagonistas de Hormonas/farmacología , Células del Estroma/efectos de los fármacos , Adulto , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Células Cultivadas , Implantación del Embrión/efectos de los fármacos , Implantación del Embrión/fisiología , Transferencia de Embrión , Endometrio/citología , Femenino , Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Humanos , Recién Nacido , Masculino , Inducción de la Ovulación/efectos adversos , Inducción de la Ovulación/métodos , Embarazo , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Estudios Retrospectivos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Células del Estroma/fisiologíaRESUMEN
Objective: To study the effect of mahogunin ring finger-1 (MGRN1) on the mitophagy of the spermatogonial stem cells (SSC) in mice. METHODS: SSCs cultured in vitro were divided into three groups: empty vector control, MGRN1 (MGRN1 in SSCs knocked down by RNAi), and MGRN1 + FCCP (inducing mitophagy with carbonyl cyanide p-trifluoromethoxyphenylhydrazone ï¼»FCCPï¼½ in the SSCs with down-regulated MGRN1). The expressions of mitochondrial function-related proteins (Cytochromo c and COX IV) and mitophagy-related proteins (LC3, P62, FUNDC1 and CK2) and the phosphorylation of FUNDC1 were detected by Western blot. Mitochondria and mitochondrial autophagosomes in the SSCs were observed under the electron microscope. RESULTS: Compared with the empty vector control group, the MGRN1 and MGRN1 + FCCP groups showed significantly down-regulated expressions of Cytochromo c, Cox IV, LC3 and P62, increased phosphorylation level of FUNDC1, and up-regulated expression of CK2 in the SSCs (P < 0.05). No statistically significant differences were found in the expressions of Cytochromo c, Cox IV, LC3, P62 and CK2 or in the phosphorylation level of FUNDC1 between the MGRN1 and MGRN1 + FCCP groups (P > 0.05). Electron microscopy manifested increased mitochondrial damage and reduced mitochondrial autophagosomes in the SSCs in the MGRN1 and MGRN1 + FCCP groups compared with those in the control group. CONCLUSIONS: MGRN1 affects mitophagy in the SSCs of mice, which may be associated with the effect of CK2 on the phosphorylation of FUNDC1, and its molecular mechanism needs to be further studied.
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Oxidative stress (OS) has been proposed to play a role in the development of EMs. Peroxiredoxins are a family of antioxidant proteins that exhibit peroxidase activity in a thioredoxin-dependent manner, protecting cells against OS. The Western blotting results showed that the relative expression of PRDX4 was significantly increased in ectopic endometria compared with the normal endometria of EMs-free (p < .05). The H2O2 concentration was also significantly higher in the ectopic endometrium. PRDX4 siRNA was transfected into primary ectopic endometrial stromal cells (EESCs). The viability of the transfected EESCs was measured by CCK-8 assay, and the results showed significantly decreased cell viability. Furthermore, the apoptosis rate and ROS generation in flow cytometry assays were significantly increased after the knockdown of PRDX4 expression (p < .05). Scratch assays and transwell assays revealed that decreased expression of PRDX4 mediated by siRNA inhibited EESC migration and invasion. In conclusion, these findings indicate the potential role of PRDX4 in the development of EMs and PRDX4 as a possible therapeutic target for EMs treatment.
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Endometriosis/metabolismo , Peroxirredoxinas/antagonistas & inhibidores , ARN Interferente Pequeño/uso terapéutico , Estudios de Casos y Controles , Proliferación Celular/efectos de los fármacos , Endometriosis/terapia , Femenino , Humanos , Terapia Molecular Dirigida , Peroxirredoxinas/metabolismo , ARN Interferente Pequeño/farmacología , Especies Reactivas de Oxígeno/metabolismo , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismoRESUMEN
OBJECTIVE: To study the effect of mahogunin ring finger-1 (MGRN1) on the autophagy of Sertoli cells in mice. METHODS: Using RNA interference, we down-regulated the expression of MGRN1 in the mouse TM4 Sertoli cells cultured in vitro, determined the expressions of the autophagy-related proteins LC3-II/I, ATG-5 and ATG-7 by Western blot, and detected the autophagosomes in the TM4 cells by immunofluorescence and electron microscopy. RESULTS: Western blot showed increased expressions of LC3-II/I, ATG-5 and ATG-7 in the mouse TM4 Sertoli cells after knockdown of MGRN1. Fluorescence microscopy revealed significantly more autophagosomes in the TM4 cells than in the control group (P < 0.05). CONCLUSIONS: MGRN1 affects the autophagy of mouse Sertoli cells, and its specific molecular mechanism needs to be further studied.
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Autofagia , Células de Sertoli/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Western Blotting , Técnicas de Silenciamiento del Gen , Masculino , Ratones , Células de Sertoli/citologíaRESUMEN
OBJECTIVE: To provide a scientific evaluation of the food safety of the rice biofortified with ß-glucan. METHODS: The acute toxicity and genotoxicity of the rice were evaluated by 14-day feeding experiment, Ames experiment, erythrocyte micronucleus test and mouse lymphoma thymidine kinase gene ( TK) mutation assay respectively. RESULTS: In the acute toxicity test, there was no obvious toxicity of rice biofortified with ß-glucan, and no abnormality was found in anatomical observation. The median lethal dose (LD 50) to rats and mice wereall greater than 15 mg/kg, which belonged to the actual non-toxic level. Whether with S 9 activation or not, no genotoxicity was found to the tested strains TA97a, TA98, TA100, TA102 and TA1535. No induction of polychromatic erythrocytes and inhibition of bone marrow were found in erythrocyte micronucleus test. The results of TK gene mutation assay did not show the mutagenicity of ß-glucan bioaugmentation rice. All results of the three genotoxicity tests were negative. CONCLUSION: Under the current experimental conditions, ß-glucan biofortified rice showed no obvious acute toxicity and genotoxicity.
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Contaminación de Alimentos/análisis , Oryza , beta-Glucanos , Animales , Daño del ADN/efectos de los fármacos , Dosificación Letal Mediana , Ratones , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Oryza/química , Ratas , beta-Glucanos/toxicidadRESUMEN
Photodynamic therapy (PDT) is a promising singlet oxygen ((1)O2) mediated clinical treatment for many tumors. As the source of (1)O2, oxygen plays an important role in the curative effect of PDT. However, the facts of photochemical depletion of oxygen and the intrinsic hypoxic microenvironment of tumors remain the major challenges. In this work, a novel photosensitizer carrier with oxygen self-compensating ability was designed for PDT. It was synthesized via chemical conjugation of hemoglobin (Hb) to polymeric micelles formed by triblock copolymers of poly(ethylene glycol)-block-poly(acrylic acid)-block-polystyrene (PEG-b-PAA-b-PS). The PEG-b-PAA-b-PS and resultant micelles in aqueous solution were comprehensively characterized by means of FTIR, (1)H NMR, GPC, DLS, TEM, and fluorescence spectroscopy. The oxygen-binding capacity and antioxidative activity of the Hb conjugated micelles were evaluated via UV-vis spectroscopy. In addition, compared with the control micelles without Hb, the Hb conjugated photosensitizer carrier was able to generate more (1)O2 and exert greater photocytotoxicity on Hela cells in vitro.
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Hemoglobinas , Indoles , Micelas , Oxígeno , Fotoquimioterapia , Polietilenglicoles , Citotoxinas/síntesis química , Citotoxinas/química , Citotoxinas/farmacología , Células HeLa , Hemoglobinas/química , Hemoglobinas/farmacología , Humanos , Indoles/química , Indoles/farmacología , Isoindoles , Oxígeno/química , Oxígeno/farmacología , Polietilenglicoles/química , Polietilenglicoles/farmacología , Zinc/químicaRESUMEN
BACKGROUND: Adenomyosis is a specific subtype of endometriosis and recent evidences have indicated that Tanshinone IIA (TSIIA) might be a potential therapeutic option for endometriosis. Meanwhile, endometrial stromal cells (ESCs) of adenomyosis might play crucial roles in the progression of this disease, emphasizing the importance of targeting ESCs in the treatment of adenomyosis. Furthermore, previous evidences also implicated that deregulated 14-3-3ζ expression might be associated with therapeutic effects of certain drugs. AIM OF THE STUDY: The aim of this study is to evaluate the potential involvement of 14-3-3ζ in the process of TSIIA-treated adenomyosis. MATERIALS AND METHODS: Ectopic endometrial stromal cells (EESCs) were isolated from a total of 3 patients with adenomyosis. Cells were treated with TSIIA and infected with 14-3-3ζ-overexpressing adenovirus, the expression level of 14-3-3ζ was determined by western blotting (WB), cell viability was detected by Cell Counting Kit-8 (CCK8), cell invasion and migration was evaluated by transwell assay, and cell apoptosis was detected by flow cytometry. RESULTS: TSIIA could decrease cell viability, induce cell apoptosis, and inhibit cell migration and invasion in EESCs. Mechanistically, TSIIA markedly reduced the expression of 14-3-3ζ in EESCs, and overexpression of 14-3-3ζ could restore the ability of cell viability, migration and invasion, but has no effect on cell apoptosis. CONCLUSIONS: TSIIA could be a promising novel therapeutic agent for adenomyosis, via inducing cell apoptosis, inhibiting cell viability, migration and invasion in EESCs. Furthermore, the effects of cell viability, migration and invasion were mediated in 14-3-3ζ-dependent manner while that of cell apoptosis was mediated in 14-3-3ζ-independent manner.
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Proteínas 14-3-3/metabolismo , Abietanos/farmacología , Adenomiosis/metabolismo , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Movimiento Celular/genética , Endometrio/metabolismo , Células del Estroma/metabolismo , Proteínas 14-3-3/genética , Adenomiosis/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/genética , Regulación hacia Abajo , Endometriosis/metabolismo , Endometrio/patología , Células Epiteliales/metabolismo , Femenino , Humanos , Células del Estroma/patologíaRESUMEN
BACKGROUND: Granulocyte colony-stimulating factor (G-CSF) has been shown to reduce lesion volume and improve functional outcome in experimental stroke models. However, whether G-CSF plays a role currently in patients with stroke remains uncertain. Our study aimed at examining the efficacy and safety of G-CSF in patients with acute ischemic stroke. METHODS: A comprehensive search was conducted in 5 online databases up to April 2014, and 10 studies with 711 patients met the criteria. RESULTS: The results showed that G-CSF was beneficial in improving the National Institutes of Health Stroke Scale (standardized mean difference [SMD], .43; 95% confidence interval [CI], .03-.82; P = .04) and modified Rankin Scale (mRS) scores (SMD, .72; 95% CI, .51-.93; P = .01), and elevating CD34(+) count (P < .001). No treatment effects were found in Barthel Index scores (SMD, -.13; 95% CI, -.61 to .35; P = .59), serious adverse events (relative ratio [RR], 1.12; 95% CI, .91-1.38; P = .28), or the death of serious adverse events (RR, 1.25; 95% CI, .82-1.91; P = .30) between groups at day 90. Adverse effect on vascular complications was not detected to be increased although G-CSF produced a marked elevation in the total leukocyte count (SMD, 3.52; 95% CI, 2.54-4.49; P < .001). CONCLUSIONS: In conclusion, G-CSF is effective at mobilizing bone marrow-derived CD34(+) stem cells to the peripheral blood. It also seems to improve the National Institutes of Health Stroke Scale and mRS scores. The administration of G-CSF appears to be safe and well tolerated. Further studies need to be done on a large sample to verify or fully characterize the results.
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Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Bases de Datos Bibliográficas/estadística & datos numéricos , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Doxycycline hyclate (DOX-h) attenuates inflammatory conditions independent of its antimicrobial effect. This study aimed to observe the effects of DOX-h on lipopolysaccharide (LPS)-induced endothelial barrier dysfunction. The endothelial monolayer permeability of human umbilical vein endothelial cells (HUVECs) was monitored by transendothelial electrical resistance (TEER). The phosphorylation of mitogen-activated protein kinases (MAPKs) and the arrangement of F-actin were detected. The results showed that both pretreatment and simultaneous treatment with DOX-h markedly attenuated the LPS-induced reduction in TEER and the disorganization of F-actin on HUVECs in a dose- and time-dependent manner. LPS mediated the phosphorylation of all three MAPKs (p38, extracellular signal-regulated kinase (ERK)1/2, and c-Jun N-terminal kinase (JNK)), but DOX-h was only able to inhibit the LPS-induced phosphorylation of p38 and JNK. The data further suggested that DOX-h alleviated LPS-evoked TEER reduction and F-actin redistribution by inhibiting the phosphorylation of p38 and its downstream target, heat shock protein (HSP)27. Thus, DOX-h attenuates LPS-induced endothelial barrier dysfunction via inhibition of the p38 MAPK-HSP27-F-actin pathway.
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Doxiciclina/farmacología , Células Endoteliales/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Lipopolisacáridos/toxicidad , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Antibacterianos/farmacología , Células Cultivadas , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Permeabilidad/efectos de los fármacosRESUMEN
In this paper, the problem of highly performance motion control of tank bidirectional stabilizer with dead zone nonlinearity and uncertain nonlinearity is addressed. First, the electromechanical coupling dynamics model of bidirectional stabilizer is developed finely. Second, the dead zone nonlinearity in bidirectional stabilizer is characterized as the combination of an uncertain time-varying gain and a bounded disturbance term. Meanwhile, an adaptive robust controller with dead zone compensation is proposed by organically combining adaptive technique and extended state observer (ESO) through backstepping method. The adaptive technique is employed to reduce the impact of unknown system parameter and dead zone parameter. Furthermore, the ESO is constructed to compensate the lumped uncertainties including unmodeled dynamics and dead zone residual, and integrated together via a feedforward cancellation technique. Moreover, the adaptive robust control law is derived to ensure final global stability. In stability analysis, the asymptotic tracking performance of the proposed controller can be guaranteed as the uncertainty nonlinearities in tank bidirectional stabilizer are constant. It is also guaranteed to achieve bounded tracking performance when time-varying uncertainties exist. Extensive co-simulation and experimental results verify the superiority of the proposed strategy.
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The purpose of this study was to evaluate the integrative effects of visual stimuli with chemical senses (olfactory and gustatory) stimuli in humans. Noninvasive measurement tools such as magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) are used to describe the mechanism of olfactory information processing in the human brain, and the neurophysiological properties of olfactory-related neurons are described. The first study analyzed the interaction between visual and olfactory stimuli. Two odors (lemon and iso-valeric acid) were selected as pleasant and unpleasant odors, respectively and pleasant and unpleasant images were also selected. These cross-modal stimulus combinations were presented to the subject at random, and responses were measured by fMRI using an event related task. These results revealed that active brain areas with pleasant/unpleasant stimuli and matched/mismatched stimuli were different for memory and cognition. The second study analyzed the interaction between visual and gustatory stimuli. Total four conditions (hunger-not hunger, and intake-not intake of monosodium glutamate (MSG)) were tested. Visual stimuli were food-related and nonfood-related photos. A visual analog scale (VAS) was also used to evaluate before and at regular time intervals after intake of MSG, and responses were measured using fMRI. Brain activity related to feeding desire after intake of MSG occurred near the insula cortex, and orbito-frontal cortex, among other areas. These results on the integrative effects of visual stimuli with olfactory and gustatory stimuli, cross-modal and complex effects on olfaction and gustation were suggested to be obtained as an emotional response such as "pleasantness/unpleasantness" and as cognitive and memory responses such as "matching/mismatching" or the responses such as "feeding desire" afterwards intake of foods.
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Mapeo Encefálico/métodos , Encéfalo/fisiología , Emociones/fisiología , Percepción Olfatoria/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Imagen Multimodal , Estimulación Luminosa , Adulto JovenRESUMEN
This paper presents the experimental results of cogasification of coal and biomass in an intermittent fluidized bed reactor, aiming to investigate the influences of operation parameters such as gasification temperature (T), steam to biomass mass ratio (SBMR), and biomass to coal mass ratio (BCMR) on hydrogen-rich (H2-rich) gas production. The results show that H2-rich gas free of N2 dilution is produced and the H2 yield is in the range of 18.25~68.13 g/kg. The increases of T, SBMR, and BCMR are all favorable for promoting the H2 production. Higher temperature contributes to higher CO and H2 contents, as well as H2 yield. The BCMR has a weak influence on gas composition, but the yield and content of H2 increase with BCMR, reaching a peak at the BCMR of 4. The H2 content and yield in the product gas increase with SBMR, whilst the content of CO increases first and then decreases correspondingly. At a typical case, the relative linear sensitivity coefficients of H2 production efficiency to T, SBMR, and BCMR were calculated. The results reveal that the order of the influence of the operation parameters on H2 production efficiency is T > SBMR > BCMR.
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Biocombustibles , Biomasa , Reactores Biológicos , Carbón Mineral , Hidrógeno/química , Monóxido de Carbono/químicaRESUMEN
When caring for an older relative with dementia, family members experience considerable distress and burden. Literature reviews show that supportive group interventions for these caregivers have significant positive effects on improving their distress and quality of life, but not consistent and conclusive. Limited research is found in Asian populations. This study tested the effectiveness of a 12-session bi-weekly mutual support group program for Chinese family caregivers of a relative with dementia in Hong Kong, when compared with standard family support service. An experimental study with pre- and post-test, parallel groups design was conducted. A randomized sample of 78 family caregivers, 39 in each of the experimental and control groups, from one regional dementia care center participated in the study. A protocol was specifically designed by an advanced practice nurse to guide the mutual support group process and the facilitator and peer leader training, based on evidence from the literature on family support group intervention in Western countries. The results of ANOVA tests indicated that the mutual support group participants had significantly greater improvements in distress levels and quality of life than the control group. There were only mild changes in the demands for mental health services in both groups at post-test. These findings support the effectiveness of mutual support groups to offer psychosocial support to Chinese family caregivers in dementia care beyond routine community mental health care.
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Cuidadores/psicología , Demencia/enfermería , Familia/psicología , Grupos de Autoayuda , China , HumanosRESUMEN
Attention deficit hyperactivity disorder (ADHD) is the most common neurobehavioral childhood disorder in which parental care-giving is found very stressful. Limited qualitative research is found on their care-giving experiences. This study aimed to explore Chinese parents' experiences of care-giving to a child with ADHD at home. It was conducted at one Child and Adolescent Mental Health Unit in Hong Kong using qualitative exploratory approach. A purposive sample of 12 parents was recruited. Semi-structured interviews were conducted, each lasting about one hour. Content analysis was used to analyze the data. From the interview data, four themes were identified, including: concept of the illness, barriers to child care in ADHD, psychological effects in care-giving, and positive aspects of care-giving. The parents indicated a variety of life problems and health concerns in care-giving. The findings may help nurses understand the perceptions and barriers towards parental care of a child with ADHD in a Chinese population and consider parents' educational needs in care-giving.
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Trastorno por Déficit de Atención con Hiperactividad/enfermería , Cuidadores/psicología , Padres/psicología , Adulto , Trastorno por Déficit de Atención con Hiperactividad/psicología , Niño , Cuidado del Niño , Hong Kong , HumanosRESUMEN
The thermo-sensitive hydrogel formed by triblock copolymers of polyethylene glycols and aliphatic polyesters serves as a promising candidate for bioink due to its excellent biodegradability and biocompatibility. However, the thermo-crosslinking alone cannot achieve a robust hydrogel to support the 3D printed constructs without collapse. Herein, a photo-crosslinkable group was introduced into the triblock copolymers to achieve a dual-sensitive hydrogel. A triblock copolymer poly(lactide-co-glycolide)-polyethylene glycol-poly(lactide-co-glycolide) decorated with acrylate group in the chain end was prepared. The obtained aqueous solutions of the copolymers could transform into hydrogels with excellent shear thinning properties and rapid elastic recovery properties spontaneously on the increase of temperature. The resulted thermogels also allowed for photo-crosslinking by exposure to ultraviolet radiation, with storage modulus dramatically increased to stable the printed constructs. Through a two-step crosslinking strategy, complicated tissue-like constructs with high shape fidelity can be printed using the dual-sensitive inks. Moreover, the mechanical strength, swelling ratio, and printability of the hydrogels can be tuned by varying the substitution rate of the acrylate group without compromising the inks' extrudability. We expect that the dual-sensitive hydrogels may be used as bioinks to print large constructs for applications in tissue engineering.
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The hydrogel formed by polyethylene glycol-aliphatic polyester block copolymers is an ideal bioink and biomaterial ink for three-dimensional (3D) bioprinting because of its unique temperature sensitivity, mild gelation process, good biocompatibility, and biodegradability. However, the gel forming mechanism based only on hydrophilic-hydrophobic interaction renders the stability and mechanical strength of the formed hydrogels insufficient, and cannot meet the requirements of extrusion 3D printing. In this study, cellulose nanocrystals (CNC), which is a kind of rigid, hydrophilic, and biocompatible nanomaterial, were introduced to enhance the hydrogels so as to meet the requirements of extrusion 3D printing. First, a series of poly(ε-caprolactone/lactide)-b-poly(ethylene glycol)-b-poly(ε-caprolactone/lactide) (PCLA-PEG-PCLA) triblock copolymers with different molecular weights were prepared. The thermodynamic and rheological properties of CNC-enhanced hydrogels were investigated. The results showed that the addition of CNC significantly improved the thermal stability and mechanical properties of the hydrogels, and within a certain range, the enhancement effect was directly proportional to the concentration of CNC. More importantly, the PCLA-PEG-PCLA hydrogels enhanced by CNC could be extruded and printed through temperature regulation. The printed objects had high resolution and fidelity with effectively maintained structure. Moreover, the hydrogels have good biocompatibility with a high cell viability. Therefore, this is a simple and effective strategy. The addition of the hydrophilic rigid nanoparticles such as CNC improves the mechanical properties of the soft hydrogels which made it able to meet the requirements of 3D bioprinting.
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Temperature-sensitive hydrogels with mild gel-forming process, good biocompatibility and biodegradability have been widely studied as bioinks and biomaterial inks for 3D bioprinting. However, the hydrogels synthesized via copolymerization of aliphatic polyesters and polyethylene glycols have low mechanical strength and cannot meet the needs of 3D printing. In this paper, we propose a strategy of enhancing the strength of hydrogels by introducing crystallization between blocks to meet the requirements of 3D bioprinting inks. A series of polycaprolactone-polyethylene glycol-polycaprolactone (PCL-PEG-PCL) triblock polymers were prepared by ring-opening polymerization, of which the strong crystallinity of polycaprolactone blocks improved the printability and enhanced the mechanical properties of the ink. It was found that the resulted hydrogels were temperature-responsive, and the PCL blocks could form a crystalline phase in the state of the hydrogel, thereby significantly increasing the modulus of the hydrogel. Moreover, the mechanical strength of the hydrogel could be adjusted by changing the composition ratio of each block of the copolymer. The 3D printing results showed that the PCL-PEG-PCL hydrogel with crystallinity can not only be extruded and printed via temperature adjustment, but also the three-dimensional structure can be effectively maintained after 3D printing. The gels demonstrated good cell compatibility, and the cell survival rate was maintained at a high level.
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Hidrogeles , Poliésteres , Cristalización , Hidrogeles/química , Poliésteres/química , Polietilenglicoles/química , Polímeros , Impresión TridimensionalRESUMEN
Viral infections seriously affect the health of organisms including humans. Now, more and more researchers believe that microRNAs (miRNAs), one of the members of the non-coding RNA family, play significant roles in cell biological function, disease occurrence, and immunotherapy. However, the roles of miRNAs in virus infection (entry and replication) and cellular immune response remain poorly understood, especially in low vertebrate fish. In this study, based on the established virus-cell infection model, Singapore grouper iridovirus (SGIV)-infected cells were used to explore the roles of miR-124 of Epinephelus coioides, an economically mariculture fish in southern China and Southeast Asia, in viral infection and host immune responses. The expression level of E. coioides miR-124 was significantly upregulated after SGIV infection; miR-124 cannot significantly affect the entry of SGIV, but the upregulated miR-124 could significantly promote the SGIV-induced cytopathic effects (CPEs), the viral titer, and the expressions of viral genes. The target genes of miR-124 were JNK3/p38α mitogen-activated protein kinase (MAPK). Overexpression of miR-124 could dramatically inhibit the activation of NF-κB/activating protein-1 (AP-1), the transcription of proinflammatory factors, caspase-9/3, and the cell apoptosis. And opposite results happen when the expression of miR-124 was inhibited. The results suggest that E. coioides miR-124 could promote viral replication and negatively regulate host immune response by targeting JNK3/p38α MAPK, which furthers our understanding of virus and host immune interactions.
Asunto(s)
Lubina/virología , Infecciones por Virus ADN/veterinaria , Enfermedades de los Peces/inmunología , Iridovirus/fisiología , MicroARNs/fisiología , Replicación Viral , Animales , Apoptosis , Infecciones por Virus ADN/inmunología , Inmunidad Innata , Proteína Quinasa 10 Activada por Mitógenos/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/fisiologíaRESUMEN
BACKGROUND: It has been a global trend that increasing complications related to pelvic floor surgeries have been reported over time. The current study aimed to outline the development of Chinese pelvic floor surgeries related to pelvic organ prolapse (POP) over the past 14 years and investigate the potential influence of enhanced monitoring conducted by the Chinese Association of Urogynecology since 2011. METHODS: A total of 44,594 women with POP who underwent pelvic floor surgeries between October 1, 2004 and September 30, 2018 were included from 22 tertiary academic medical centers. The data were reported voluntarily and obtained from a database. We compared the proportion of each procedure in the 7 years before and 7 years after September 30, 2011. The data were analyzed by performing Z test (one-sided). RESULTS: The number of different procedures during October 1, 2011-September 30, 2018 was more than twice that during October 1, 2004-September 30, 2011. Regarding pelvic floor surgeries related to POP, the rate of synthetic mesh procedures increased from 38.1% (5298/13,906) during October 1, 2004-September 30, 2011 to 46.0% (14,107/30,688) during October 1, 2011-September 30, 2018, whereas the rate of non-mesh procedures decreased from 61.9% (8608/13,906) to 54.0% (16,581/30,688) (Z = 15.53, Pâ<â0.001). Regarding synthetic mesh surgeries related to POP, the rates of transvaginal placement of surgical mesh (TVM) procedures decreased from 94.1% (4983/5298) to 82.2% (11,603/14,107) (Z = 20.79, Pâ<â0.001), but the rate of laparoscopic sacrocolpopexy (LSC) procedures increased from 5.9% (315/5298) to 17.8% (2504/14,107). CONCLUSIONS: The rate of synthetic mesh procedures increased while that of non-mesh procedures decreased significantly. The rate of TVM procedures decreased while the rate of LSC procedures increased significantly. TRIAL REGISTRATION NUMBER: NCT03620565, https://register.clinicaltrials.gov.