Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Mater Horiz ; 11(15): 3548-3560, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-38869226

RESUMEN

Future electronics call for materials with mechanical toughness, flexibility, and stretchability. Moreover, self-healing and recyclability are highly desirable to mitigate the escalating environmental threat of electronic waste (e-waste). Herein, we report a stretchable, self-healing, and recyclable material based on a mixture of the conductive polymer poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) with a custom-designed polyurethane (PU) and polyethylene glycol (PEG). This material showed excellent elongation at brake (∼350%), high toughness (∼24.6 MJ m-3), moderate electrical conductivity (∼10 S cm-1), and outstanding mechanical and electrical healing efficiencies. In addition, it demonstrated exceptional recyclability with no significant loss in the mechanical and electrical properties after being recycled 20 times. Based on these properties, as a proof of principle for sustainable electronic devices, we demonstrated that electrocardiogram (ECG) electrodes and pressure sensors based on this material could be recycled without significant performance loss. The development of multifunctional electronic materials that are self-healing and fully recyclable is a promising step toward sustainable electronics, offering a potential solution to the e-waste challenge.

2.
Front Sports Act Living ; 5: 1305175, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38143784

RESUMEN

Since the outset of the COVID-19 pandemic, the global healthcare community has faced the challenge of understanding and addressing the ongoing and multi-faceted SARS-CoV-2 infection outcomes. As millions of individuals worldwide continue to navigate the complexities of post-hospitalization recovery, reinfection rates, and the increasing prevalence of Long-COVID symptoms, comprehensive COVID-19 rehabilitation strategies are greatly needed. Previous studies have highlighted the potential synergy between exercise and nutrition, suggesting that their integration into patient rehabilitation programs may yield improved clinical outcomes for survivors of COVID-19. Our group aimed to consolidate existing knowledge following the implementation of patient, intervention, comparison, and outcome (PICO) search strategies on the distinct and combined impacts of exercise and nutrition interventions in facilitating the recovery of COVID-19 patients following hospitalization, with a specific focus on their implications for both public health and clinical practice. The incorporation of targeted nutritional strategies alongside exercise-based programs may expedite patient recovery, ultimately promoting independence in performing activities of daily living (ADLs). Nonetheless, an imperative for expanded scientific inquiry remains, particularly in the realm of combined interventions. This mini-review underscores the compelling prospects offered by an amalgamated approach, advocating for the seamless integration of exercise and nutrition as integral components of post-hospitalization COVID-19 rehabilitation. The pursuit of a comprehensive understanding of the synergistic effects and effectiveness of exercise and nutrition stands as a crucial objective in advancing patient care and refining recovery strategies in the wake of this enduring global health crisis.

3.
Polymers (Basel) ; 15(22)2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38006132

RESUMEN

Self-healing polymeric materials, engineered to autonomously self-restore damages from external stimuli, are at the forefront of sustainable materials research. Their ability to maintain product quality and functionality and prolong product life plays a crucial role in mitigating the environmental burden of plastic waste. Historically, initial research on the development of self-healing materials has focused on extrinsic self-healing systems characterized by the integration of embedded healing agents. These studies have primarily focused on optimizing the release of healing agents and ensuring rapid self-healing capabilities. In contrast, recent advancements have shifted the focus towards intrinsic self-healing systems that utilize their inherent reactivity and interactions within the matrix. These systems offer the advantage of repeated self-healing over the same damaged zone, which is attributed to reversible chemical reactions and supramolecular interactions. This review offers a comprehensive perspective on extrinsic and intrinsic self-healing approaches and elucidates their unique properties and characteristics. Furthermore, various self-healing mechanisms are surveyed, and insights from cutting-edge studies are integrated.

4.
Polymers (Basel) ; 15(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38231957

RESUMEN

In this study, we prepare highly self-healable polymeric coating materials using charge transfer complex (CTC) interactions. The resulting coating materials demonstrate outstanding thermal stability (1 wt% loss thermal decomposition temperature at 420 °C), rapid self-healing kinetics (in 5 min), and high self-healing efficiency (over 99%), which is facilitated by CTC-induced multiple interactions between the polymeric chains. In addition, these materials exhibit excellent optical properties, including transmittance over 91% and yellow index (YI) below 2, and show enhanced weatherability with a ΔYI value below 0.5 after exposure to UV light for 72 h. Furthermore, the self-healable coating materials developed in this study show outstanding mechanical properties by overcoming the limitations of conventional self-healing materials.

5.
Polymers (Basel) ; 14(23)2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36501576

RESUMEN

Polymeric coating materials (PCMs) are promising candidates for developing next-generation flexible displays. However, PCMs are frequently subjected to external stimuli, making them highly susceptible to repeated damage. Therefore, in this study, a highly self-healing PCM based on a charge transfer complex (CTC) was developed, and its thermal, self-healing, and mechanical properties were examined. The self-healing material demonstrated improved thermal stability, fast self-healing kinetics (1 min), and a high self-healing efficiency (98.1%) via CTC-induced multiple interactions between the polymeric chains. In addition, it eliminated the trade-off between the mechanical strength and self-healing capability that is experienced by typical self-healing materials. The developed PCM achieved excellent self-healing and superior bulk (in-plane) and surface (out-of-plane) mechanical strengths compared to those of conventional engineering plastics such as polyether ether ketone (PEEK), polysulfone (PSU), and polyethersulfone (PES). These remarkable properties are attributed to the unique intermolecular structure resulting from strong CTC interactions. A mechanism for the improved self-healing and mechanical properties was also proposed by comparing the CTC-based self-healing PCMs with a non-CTC-based PCM.

6.
J Korean Med Sci ; 37(27): e224, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35818706

RESUMEN

A rapid outbreak of monkeypox is ongoing in non-endemic countries since May 2022. We report the first case of monkeypox in the Republic of Korea. This occurred in a 34-year-old male patient who traveled to Europe in June 2022. On the day of his return to the Republic of Korea (June 21, 2022), the patient presented with a genital lesion. The results of the monkeypox real-time polymerase chain reaction tests were positive in the penile ulcer, oropharyngeal and nasopharyngeal specimens. The patient subsequently developed fever and skin rash after hospital admission. Careful history taking along physical examination should be conducted in the patients who have epidemiologic risk factors for monkeypox. Moreover, appropriate specimens should be obtained from lesions and tested for the monkeypox virus.


Asunto(s)
Exantema , Mpox , Adulto , Brotes de Enfermedades , Fiebre/etiología , Humanos , Masculino , Mpox/diagnóstico , Mpox/epidemiología , Monkeypox virus , República de Corea/epidemiología
7.
Diabetes Res Clin Pract ; 171: 108608, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33310123

RESUMEN

AIM: To identify the influence of prepregnancy hemoglobin levels on gestational diabetes mellitus. MATERIALS AND METHODS: Korean women who had given birth between January 1st, 2006 and December 31st, 2015 and who had undergone a biannual national health screening examination within 6 months prior to pregnancy were enrolled. Subjects were divided into three groups according to their hemoglobin levels. Multivariate logistic regression analysis was used to estimate the adjusted odds ratio and 95% confidence interval for GDM. RESULTS: Of the 366,122 participants, GDM developed in 14,799 (4%) women. More specifically, GDM developed in 3.6% of women with prepregnancy anemia (hemoglobin < 11 g/dL), 3.57% with normal hemoglobin levels, and 4.47% with hemoglobin levels higher than 13 g/dL. We did not find any association between prepregnancy anemia and the risk of developing GDM (OR 1.002 [95% CI 0.90-1.11]). After adjusting for potential confounding factors (adjusted odds ratio 1.41; 95% CI 1.29-1.54), high hemoglobin levels were associated with insulin requiring GDM. CONCLUSIONS: Our study identified an association between high prepregnancy hemoglobin levels and GDM risk.


Asunto(s)
Diabetes Gestacional/sangre , Hemoglobinas/metabolismo , Adulto , Femenino , Humanos , Embarazo
8.
Diabetes Res Clin Pract ; 171: 108533, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33157117

RESUMEN

AIMS: Pre-pregnancy insulin resistance is one of the main pathophysiologies of gestational diabetes mellitus (GDM). Triglyceride-glucose (TyG) index is a marker of insulin resistance. We aimed to evaluate the association between pre-pregnancy TyG index and GDM in primipara women. METHODS: A total of 380,208 women who underwent a Korean national health screening exam within 2 years before their first delivery, between January 1, 2012 and December 31, 2015, were included. The TyG index was calculated as ln [triglyceride (mg/dL) × fasting plasma glucose (mg/dL)/2]. RESULTS: Among the 380,208 primipara women, 17,239 women were diagnosed with GDM (4.53%). Multivariate logistic regression analysis adjusted for risk factors showed a higher odds ratio of 1.73 for GDM (95% CI 1.65-1.81) in the highest quartile than that in the lowest quartile. A 1-SD increase in the TyG index increased the risk of GDM (31%) and GDM requiring insulin therapy (82%) in the fully adjusted model. A 1-unit increase in the TyG index significantly increased the risk of GDM and GDM requiring insulin treatment by 1.81 and 3.69 times, respectively.The impact of a high TyG index on the risk of GDM was more profound in the subjects aged ≥ 35 years, with obesity, with impaired fasting glucose, who are current smokers, and with a family history of diabetes mellitus. CONCLUSIONS: Increased pre-pregnancy TyG index is associated with a risk of GDM. Elevation of the TyG index may be an early marker of GDM.


Asunto(s)
Biomarcadores/sangre , Glucemia/metabolismo , Diabetes Gestacional/sangre , Triglicéridos/sangre , Adulto , Estudios de Cohortes , Diabetes Mellitus Tipo 2/sangre , Femenino , Humanos , Embarazo , Factores de Riesgo
9.
Med Sci Monit ; 26: e926395, 2020 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-33139690

RESUMEN

BACKGROUND The purpose of this study was to investigate the effects of sevoflurane on cancer immunosurveillance and metastasis in non-small-cell lung cancer (NSCLC). MATERIAL AND METHODS NCI-H23 cells, a human NSCLC cell line, were incubated with or without sevoflurane at the concentrations of 0, 12.5, 25, 50, 100, and 200 µM for 6 h. Cell viability, the expression of natural killer group 2, member D ligands (NKG2D ligands: UL16-binding proteins 1-3 [ULBP1-3] and major histocompatibility complex class I chain-related molecules A/B [MICA/B]), the expression of matrix metalloproteinases (MMPs), NK cell-mediated cytotoxicity, and cancer cell migration were measured. RESULTS At 12.5, 25, 50, and 100 µM, sevoflurane increased the expression of NKG2D ligands (ULBP2-3 and MICA, ULBP1-3, ULBP1-3, and ULBP1, respectively). Sevoflurane decreased the expression of NKG2D ligands at 200 µM (MICA/B). NK cell-mediated lysis of NCI-H23 cells at 200 µM sevoflurane was significantly reduced compared with the control (P=0.025; target cell: effect cell=1: 10). Sevoflurane increased the expression of MMP-1, -2, and -9 and increased cell migration in NCI-H23 cells at 50, 100, and 200 µM (P=0.001, 0.035, and 0.039, respectively, compared with the control after 18 h of wound formation). CONCLUSIONS Sevoflurane could suppress NKG2D-mediated NK cell cytotoxicity and increased expression of MMPs and migration in NCI-H23 cells. Further research is needed to determine the effects of sevoflurane on cancer immunosurveillance and metastasis in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/inmunología , Inmunidad/efectos de los fármacos , Neoplasias Pulmonares/inmunología , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Sevoflurano/farmacología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Citotoxicidad Inmunológica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ligandos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Metaloproteinasas de la Matriz/genética , Metaloproteinasas de la Matriz/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Cicatrización de Heridas/efectos de los fármacos
10.
BMC Pregnancy Childbirth ; 20(1): 716, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-33228582

RESUMEN

BACKGROUND: Our objective was to evaluate risks of adverse obstetric outcomes in pregnancies with myoma(s) or in pregnancies following myomectomy. METHODS: We analyzed the national health insurance database, which covers almost the entire Korean population, between 2004 and 2015. The risks of adverse pregnancy outcomes in pregnancies with myoma(s) or in pregnancies following myomectomy, compared to those in women without a diagnosed myoma, were analyzed in multivariate logistic regression analysis. RESULTS: During the study period, 38,402 women with diagnosed myoma(s), 9890 women with a history of myomectomy, and 740,675 women without a diagnosed myoma gave birth. Women with a history of diagnosed myoma(s) and women with a history of myomectomy had significantly higher risks of cesarean section (aOR 1.13, 95% CI 1.1-1.16 and aOR 7.46, 95% CI 6.97-7.98, respectively) and placenta previa (aOR 1.41, 95% CI 1.29-1.54 and aOR 1.58, 95% CI 1.35-1.83, respectively), compared to women without a diagnosed myoma. And the risk of uterine rupture was significantly higher in women with previous myomectomy (aOR 12.78, 95% CI 6.5-25.13), compared to women without a diagnosed myoma, which was much increased (aOR 41.35, 95% CI 16.18-105.69) in nulliparous women. The incidence of uterine rupture was the highest at delivery within one year after myomectomy and decreased over time after myomectomy. CONCLUSIONS: Women with a history of myomectomy had significantly higher risks of cesarean section and placenta previa compared to women without a diagnosed myoma.


Asunto(s)
Cesárea/estadística & datos numéricos , Leiomioma/cirugía , Miomectomía Uterina/efectos adversos , Neoplasias Uterinas/cirugía , Rotura Uterina/etiología , Adulto , Cesárea/efectos adversos , Femenino , Humanos , Modelos Logísticos , Análisis Multivariante , Placenta Previa/etiología , Embarazo , Complicaciones del Embarazo/etiología , Resultado del Embarazo , República de Corea , Estudios Retrospectivos
11.
Clin Transl Gastroenterol ; 11(9): e00221, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32858572

RESUMEN

INTRODUCTION: Long-term glycemic variability is associated with various adverse health outcomes in patients with diabetes mellitus (DM). However, the relationship between glycemic variability and gastric cancer remains unclear. We aimed to investigate the association between glycemic variability and gastric cancer incidence in individuals without DM. METHODS: We used the Korean National Health Insurance Service data sets of claims and health checkups and included 202,562 individuals without DM. Fasting plasma glucose (FPG) variability was measured using the variability independent of the mean (VIM), coefficient of variation, SD, and average successive variability. The association between FPG variability and gastric cancer incidence was analyzed using Cox regression adjusting for age, sex, body mass index, smoking status, alcohol consumption, regular exercise, income level, family history of cancer, mean FPG level, and number/mean interval of FPG measurements. RESULTS: In total, 1,920 patients developed gastric cancer (0.95%) within a median follow-up of 5.6 (5.3, 6.4) years. The fully adjusted hazard ratio and 95% confidence interval for gastric cancer were 1.26 and 1.18-1.34, respectively, in the highest quartile of FPG variability assessed by VIM compared with that in the lowest quartile. Similar results were obtained in the normal and impaired fasting glucose groups and when using the variability indexes, including coefficient of variation, SD, and average successive variability. There was a sequential increase in the incidence of gastric cancer according to the increase in the deciles of FPG variability (P for linear trend <0.001). A 1-SD increase in FPG variability assessed by VIM was significantly associated with a 10.0% increase in gastric cancer risk in the fully adjusted model. DISCUSSION: In a DM-free population, high variability in visit-to-visit FPG levels was independently associated with an increased risk of gastric cancer.


Asunto(s)
Variación Biológica Individual , Glucemia/análisis , Ayuno/sangre , Neoplasias Gástricas/epidemiología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , República de Corea/epidemiología , Estudios Retrospectivos , Factores de Riesgo
12.
Int J Med Sci ; 17(13): 1956-1963, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32788874

RESUMEN

Objectives: The purpose of this study was to compare the effects of combined epidural-general anesthesia with those of general anesthesia alone on hemodynamic instability (intraoperative hypotension and hypertensive crisis) during pheochromocytoma and sympathetic paraganglioma surgery. Methods: A total of 119 patients' medical records were reviewed who were diagnosed as having pheochromocytoma and sympathetic paraganglioma on the basis of histological findings. Intraoperative hypotension was defined as a mean blood pressure < 60 mmHg or a decrease > 30% in baseline systolic blood pressure after adrenal vein ligation. Hypertensive crisis was defined as a systolic blood pressure > 200 mmHg or an increase > 30% in baseline systolic blood pressure during the operation. The predictor variables for intraoperative hypotension and hypertensive crisis were analyzed with logistic regression models. Data were presented as adjusted odds ratio with 95% confidence interval. Results: The independent predictors of intraoperative hypotension were an increased attenuation number on unenhanced computed tomography (1.112 [1.009-1.226], p = 0.033), a high baseline mean blood pressure (1.063 [1.012-1.117], p = 0.015), and the combined epidural-general anesthesia (5.439 [1.410-20.977], p = 0.014). In contrast, an increased attenuation number on unenhanced computed tomography was the only independent predictor of hypertensive crisis (1.087 [1.021-1.158], p = 0.009). Conclusions: The combined epidural-general anesthesia was not effective in attenuating hypertensive responses, but could have exacerbated intraoperative hypotension. These findings should be taken into account before selecting the anesthetic technique in pheochromocytoma and sympathetic paraganglioma surgery.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/cirugía , Anestesia Epidural/métodos , Anestesia General/métodos , Paraganglioma/cirugía , Feocromocitoma/cirugía , Neoplasias de las Glándulas Suprarrenales/fisiopatología , Adulto , Estudios de Cohortes , Femenino , Monitorización Hemodinámica/métodos , Humanos , Hipertensión/fisiopatología , Hipotensión/complicaciones , Hipotensión/fisiopatología , Masculino , Persona de Mediana Edad , Paraganglioma/fisiopatología , Feocromocitoma/fisiopatología , Estudios Retrospectivos
13.
Obstet Gynecol Sci ; 63(4): 440-447, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32689771

RESUMEN

OBJECTIVE: This study aimed to investigate trends in the rate of cesarean sections (CSs) in South Korea from 2006 to 2015 and identify the risk factors associated with these changes. METHODS: Using the National Health Insurance Corporation dataset, all women who gave birth between 2006 and 2015 were included in the study. We investigated 1) the mode of delivery, 2) the complication rates during pregnancy (i.e., preeclampsia and placenta previa), and 3) pre-pregnancy factors (body mass index, hypertension [HTN], diabetes mellitus [DM], and other pre-existing medical conditions), and their trends during the study period. RESULTS: Over 10 years, the rate of CS increased from 36.3% in 2006 to 40.6% in 2015 (P<0.01). The rate of CS increased in primiparous women, women with multiple pregnancy, and women with preeclampsia. Maternal age and the incidence of placenta previa also increased. In contrast, the rate of vacuum deliveries and vaginal birth after CS decreased during the study period. The rate of women with pre-pregnancy obesity and DM increased, but the rate of women with pre-pregnancy HTN decreased. CONCLUSION: The rate of CS in South Korea increased from 2006 to 2015. This trend may reflect changes in the rate of different risk factors. Identifying the causes of the increasing CS trend observed in this study will allow clinicians to monitor these factors and possibly reduce the rate of CS.

14.
Artículo en Inglés | MEDLINE | ID: mdl-32327443

RESUMEN

OBJECTIVE: Long-term glycemic variability has recently been recognized as another risk factor for future adverse health outcomes. We aimed to evaluate the risk of gestational diabetes mellitus (GDM) according to the prepregnancy long-term fasting plasma glucose (FPG) variability. RESEARCH DESIGN AND METHODS: A total of 164 053 women who delivered their first baby between January 1, 2012 and December 31, 2015, were selected from the Korean National Health Insurance data. All women underwent at least three national health screening examinations, and the last examination should be conducted within 2 years before their first delivery. GDM was defined as the presence of more than four times of claim of GDM (International Classification of Disease, 10th Revision (ICD-10) O24.4 and O24.9) or prescription of insulin under the ICD-code of GDM. FPG variability was assessed by variability independent of the mean (FPG-VIM), coefficient of variation, SD, and average successive variability. RESULTS: Among the 164 053 women, GDM developed in 6627 (4.04%). Those in the higher quartiles of FPG-VIM showed a stepwise increased risk of GDM. In fully adjusted model, the ORs for GDM was 1.22 (95% CI 1.14 to 1.31) in women with the highest FPG-VIM quartile compared with those in the lowest quartile. The risk for GDM requiring insulin therapy was 48% increase in women in the highest quartile of FPG-VIM compared with those in the lowest quartile, while that for GDM not requiring insulin therapy was 19% increase. The association between high FPG variability and the risk of GDM was intensified in the obese and aged more than 35 years women. CONCLUSIONS: Increased FPG variability in the prepregnancy state is associated with the risk of GDM independent of confounding factors. Therefore, prepregnancy FPG variability might be a surrogate marker of the risk of GDM.


Asunto(s)
Diabetes Gestacional , Glucemia , Estudios de Cohortes , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiología , Ayuno , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Embarazo
15.
Polymers (Basel) ; 12(4)2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32326281

RESUMEN

A functional polyurethane based on the heterocyclic group was synthesized and its self-healing and mechanical properties were examined. To synthesize a heterocyclic polyurethane, a polyol and a heterocyclic compound with di-hydroxyl groups at both ends were blended and the blended solution was reacted with a crosslinker containing multiple isocyanate groups. The heterocyclic polyurethane demonstrates better self-healing efficiency than the conventional polyurethane with no heterocyclic groups. Furthermore, unlike the conventional self-healing materials, the heterocyclic polyurethane examined in this study shows an outstanding recovery of the mechanical properties after the self-healing process. These results are attributed to the unique supramolecular network resulting from the strong hydrogen bonding interaction between the urethane group and the heterocyclic group in the heterocyclic polyurethane matrix.

16.
J Korean Med Sci ; 35(5): e61, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-32030925

RESUMEN

In December 2019, a viral pneumonia outbreak caused by a novel betacoronavirus, the 2019 novel coronavirus (2019-nCoV), began in Wuhan, China. We report the epidemiological and clinical features of the first patient with 2019-nCoV pneumonia imported into Korea from Wuhan. This report suggests that in the early phase of 2019-nCoV pneumonia, chest radiography would miss patients with pneumonia and highlights taking travel history is of paramount importance for early detection and isolation of 2019-nCoV cases.


Asunto(s)
Infecciones por Coronavirus , Neumonía Viral , Radiografía Torácica , Adulto , COVID-19 , China , Infecciones por Coronavirus/diagnóstico por imagen , Infecciones por Coronavirus/transmisión , Brotes de Enfermedades , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Anamnesis , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/etiología , Neumonía Viral/transmisión , República de Corea , Viaje
17.
Methods Mol Biol ; 1472: 169-85, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27671940

RESUMEN

Targeted gene deletion is a useful tool for understanding the function of a gene and its protein product. We have developed an efficient and robust gene deletion approach in yeast that employs oligonucleotide-based gene synthesis. This approach requires a deletion cassette composed of three modules: a central 1397-bp KanMX4 selection marker module and two 366-bp gene-specific flanking modules. The invariable KanMX4 module can be used in combination with different pairs of flanking modules targeting different genes. The two flanking modules consist of both sequences unique to each cassette (chromosomal homologous regions and barcodes) and those common to all deletion constructs (artificial linkers and restriction enzyme sites). Oligonucleotides for each module and junction regions are designed using the BatchBlock2Oligo program and are synthesized on a 96-well basis. The oligonucleotides are ligated into a single deletion cassette by ligase chain reaction, which is then amplified through two rounds of nested PCR to obtain sufficient quantities for yeast transformation. After removal of the artificial linkers, the deletion cassettes are transformed into wild-type diploid fission yeast SP286 cells. Verification of correct clone and gene deletion is achieved by performing check PCR and tetrad analysis. This method with proven effectiveness, as evidenced by a high success rate of gene deletion, can be potentially applicable to create systematic gene deletion libraries in a variety of yeast species.


Asunto(s)
Eliminación de Gen , Schizosaccharomyces/genética , Secuencia de Bases , Marcación de Gen , Genes Fúngicos , Mutagénesis Insercional , Oligonucleótidos/genética , Transformación Genética
18.
Oncotarget ; 7(32): 51840-51853, 2016 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-27322081

RESUMEN

Pancreatic cancer is characterized by an immunosuppressive tumor microenvironment (TME) with a profound immune infiltrate populated by a significant number of myeloid-derived suppressor cells (MDSCs). MDSCs have been increasingly recognized for their role in immune evasion and cancer progression as well as their potential as a target for immunotherapy. However, not much is known about the mechanisms regulating their behavior and function in the pancreatic TME. Here we report that pancreatic adenocarcinoma up-regulated factor (PAUF), a soluble protein involved in pancreatic tumorigenesis and metastasis, plays a role as an enhancer of tumor-infiltrating MDSC and its functional activity. We show that PAUF enhanced the accumulation of MDSCs in the spleen and tumor tissues of PAUF-overexpressing tumor cell-injected mice. In addition, PAUF was found to enhance the immunosuppressive function of MDSCs via the TLR4-mediated signaling pathway, which was demonstrated by PAUF-induced increased levels of arginase, nitric oxide (NO), and reactive oxygen species (ROS). The role of PAUF in modulating the functional properties of MDSCs was further demonstrated by the use of a PAUF-neutralizing antibody that caused a decreased number of tumor-infiltrating MDSCs and reduced MDSC immunosuppressive activity. The observations made in mice were confirmed in human pancreatic cancer patient-derived MDSCs, supporting the clinical relevance of our findings. Collectively, we conclude that the PAUF is a powerful and multifunctional promoter of tumor growth through increase and functional activation of MDSCs, suggesting therapeutic potential for targeting PAUF in pancreatic cancers.


Asunto(s)
Carcinoma Ductal Pancreático/inmunología , Lectinas/inmunología , Células Supresoras de Origen Mieloide/inmunología , Neoplasias Pancreáticas/inmunología , Escape del Tumor/inmunología , Animales , Carcinoma Ductal Pancreático/metabolismo , Línea Celular Tumoral , Humanos , Péptidos y Proteínas de Señalización Intercelular , Lectinas/metabolismo , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Ratones , Neoplasias Pancreáticas/metabolismo , Microambiente Tumoral/inmunología
19.
Biochem Biophys Res Commun ; 468(4): 606-10, 2015 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-26545776

RESUMEN

Lipid homeostasis in mammalian cells is regulated by sterol regulatory element-binding protein (SREBP) transcription factors that are activated through sequential cleavage by Golgi Site-1 and Site-2 proteases. Fission yeast SREBP, Sre1, engages a different mechanism involving the Golgi Dsc E3 ligase complex, but it is not clearly understood exactly how Sre1 is proteolytically cleaved and activated. In this study, we screened the Schizosaccharomyces pombe non-essential haploid deletion collection to identify missing components of the Sre1 cleavage machinery. Our screen identified an additional component of the SREBP pathway required for Sre1 proteolysis named rhomboid protein 2 (Rbd2). We show that an rbd2 deletion mutant fails to grow under hypoxic and hypoxia-mimetic conditions due to lack of Sre1 activity and that this growth phenotype is rescued by Sre1N, a cleaved active form of Sre1. We found that the growth inhibition phenotype under low oxygen conditions is specific to the strain with deletion of rbd2, not any other fission yeast rhomboid-encoding genes. Our study also identified conserved residues of Rbd2 that are required for Sre1 proteolytic cleavage. All together, our results suggest that Rbd2 is a functional SREBP protease with conserved residues required for Sre1 cleavage and provide an important piece of the puzzle to understand the mechanisms for Sre1 activation and the regulation of various biological and pathological processes involving SREBPs.


Asunto(s)
Péptido Hidrolasas/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/fisiología , Schizosaccharomyces/metabolismo , Proteínas de Unión a los Elementos Reguladores de Esteroles/química , Proteínas de Unión a los Elementos Reguladores de Esteroles/metabolismo , Sitios de Unión , Proliferación Celular/fisiología , Activación Enzimática , Estrés Oxidativo/fisiología , Oxígeno/metabolismo , Péptido Hidrolasas/química , Péptido Hidrolasas/fisiología , Unión Proteica , Especificidad por Sustrato
20.
Food Chem ; 189: 108-13, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26190608

RESUMEN

The aim of this study was to analyse and reduce furan in various model systems. Furan model systems consisting of monosaccharides (0.5M glucose and ribose), amino acids (0.5M alanine and serine) and/or 1.0M ascorbic acid were heated at 121°C for 25 min. The effects of food additives (each 0.1M) such as metal ions (iron sulphate, magnesium sulphate, zinc sulphate and calcium sulphate), antioxidants (BHT and BHA), and sodium sulphite on the formation of furan were measured. The level of furan formed in the model systems was 6.8-527.3 ng/ml. The level of furan in the model systems of glucose/serine and glucose/alanine increased 7-674% when food additives were added. In contrast, the level of furan decreased by 18-51% in the Maillard reaction model systems that included ribose and alanine/serine with food additives except zinc sulphate.


Asunto(s)
Carcinógenos/análisis , Aditivos Alimentarios/análisis , Furanos/análisis , Aminoácidos/química , Ácido Ascórbico/química , Cromatografía de Gases , Color , Glucosa/química , Calor , Reacción de Maillard , Modelos Biológicos , Reproducibilidad de los Resultados
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA