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1.
《Journal of endodontics》2022,48(1):102-108
IntroductionThe first outbreak of coronavirus disease 2019 (COVID-19) in the United States resulted in a nationwide closure of dental offices that created an oral health crisis. The aim of this observational study was to analyze and compare the characteristics of patients who visited 2 private endodontics offices from March 16 to May 31, 2020, compared with the same period in 2019.MethodsDemographic, diagnostic, and procedural data of 1520 (693 in 2020 and 827 in 2019) patient visits were collected. Bivariate and multiple logistic regression analyses were used to assess the impact of the COVID-19 outbreak on patient-related variables.ResultsBivariate analyses showed that the number of patient visits decreased in April and May 2020 (P < .0001). In 2020, patients’ self-reported pain level was higher, they were more frequently diagnosed with pulp necrosis and acute apical abscess, and they received more incisions for drainage (P < .05). Multiple logistic regression analyses showed that the COVID-19 outbreak was associated with less visits for older patients (>49.5 years) (odds ratio [OR] = 0.720; 95% confidence interval [CI], 0.573–0.906), more patients with kidney diseases (OR = 2.690; 95% CI, 1.143–6.331), higher levels of pain on percussion (OR = 2.277; 95% CI, 1.718–3.016), less cases with previously initiated treatment (OR = 0.242; 95% CI, 0.080–0.731), less periapical diagnoses of asymptomatic apical periodontitis (OR = 0.510; 95% CI, 0.306–0.849), and a higher number of nonsurgical root canal treatments (OR = 2.073; 95% CI, 1.397–3.074) and apicoectomies (OR = 2.799; 95% CI, 1.367-5.729).ConclusionsThese findings show that the public health burden of endodontic infections was more intense during the initial outbreak of COVID-19.  相似文献   
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The importance of the left atrial appendage (LAA) as the source of thromboembolism including stroke in patients with nonvalvular atrial fibrillation is well documented, with more than 90% of ischemic strokes related to a LAA thrombus. Although oral anticoagulation has been the standard of care, approximately 50% to 60% of patients either have contraindications to oral anticoagulation or do not continue the medication beyond the first year. This led to the development of local site-specific therapy to occlude the LAA by either surgical or transcatheter means. Despite marked advancements, incomplete LAA closure with surgical and transcatheter approaches remains frequent. The etiology of incomplete LAA closure and its clinical implications remain unclear. Multiple strategies are in development including changes in deployment techniques, a new device design, and alternative approaches to leak closure.  相似文献   
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目的探讨ω-3多不饱和脂肪酸(ω-3 poly unsaturated fatty acids,ω-3 PUFAs)对慢性移植物抗宿主病(chronic graft versus host disease,cGVH)狼疮模型小鼠的免疫调节功能影响。方法单次腹腔注射bm12小鼠淋巴细胞建立cGVH小鼠模型,造模当天分别给予90%ω-3 PUFAs和97%EPA灌胃治疗,持续14 d。通过流式细胞术检测小鼠脾脏淋巴细胞中各免疫指标,ELISA检测小鼠血清中总IgG水平。结果与正常对照组相比,cGVH组明显下调Treg亚群,明显上调TFH细胞、生发中心B细胞和浆细胞亚群;与模型对照组相比,90%ω-3和97%EPA均明显上调Treg亚群,并明显下调TFH细胞、生发中心B细胞和浆细胞亚群;且97%EPA组小鼠血清中总IgG水平明显下降。结论在cGVH狼疮小鼠模型中,ω-3 PUFAs通过增加Treg细胞,减少TFH细胞、生发中心B细胞和浆细胞,抑制IgG的分泌,从而发挥免疫抑制作用,且其免疫抑制作用可能与ω-3 PUFAs含量相关。  相似文献   
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BackgroundThere is increasing research interest regarding physical activity behavior among persons with multiple sclerosis (MS), yet there is little known about physical activity and its correlates in Black persons with MS.ObjectiveThis cross-sectional study assessed associations among social cognitive theory (SCT) variables and device-measured and self-reported physical activity in samples of Black and White persons with MS.MethodsParticipants included 67 Black and 141 White persons with MS who wore an ActiGraph accelerometer on a belt around the waist measuring moderate-to-vigorous physical activity (MVPA) for seven days and completed a battery of questionnaires. Questionnaires included demographic and clinical characteristics, leisure-time exercise, exercise self-efficacy, overcoming barriers self-efficacy, function, social support, exercise outcome expectations, and goal setting and planning.ResultsBlack participants with MS engaged in significantly less MVPA, but not sedentary behavior or light physical activity, than the White participants with MS. Black participants further had significantly lower levels of exercise self-efficacy and outcome expectations than the White sample. All SCT correlates were significantly correlated with self-reported physical activity, but only exercise and barriers self-efficacy, perceived function, and exercise goal setting were associated with device-measured MVPA. The difference in physical activity between Black and White participants with MS was accounted for by differences in exercise self-efficacy and outcome expectations.ConclusionsResearchers should consider developing behavioral interventions that target exercise self-efficacy and outcome expectations as SCT variables for increasing physical activity in Black persons with MS.  相似文献   
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Suicides by pentobarbital overdose have increased since about 2012, which appear to be influenced by technical information on active euthanasia that has spread over the Internet. We encountered a pentobarbital poisoning case of a patient with amyotrophic lateral sclerosis. A caregiver found the patient unconscious immediately after two visitors left the room. The patient was immediately transferred to the emergency hospital but eventually declared dead. A fatal concentration of pentobarbital was detected in peripheral blood samples collected in the emergency hospital and during autopsy (53.8 μg/mL and 29.4 μg/mL, respectively). Because the ratios of pentobarbital concentrations between the gastric contents and peripheral blood were 35 and 29 in the hospital and autopsy samples, respectively, it is likely that pentobarbital was administered via the gastrostomy tube. The patient had contacted the visitors through social media. Although the patient had requested the doctor perform active euthanasia and expressed a desire to end their life on social media, nobody had noticed the plan to commit suicide.  相似文献   
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目的:建立小鼠全身炎症反应综合征(SIRS)模型,探索紫萁贯众醇提取物中单体成分对羟基苄叉丙酮(4-hydroxybenzylideneacetone,HBAc),3,4-二羟基苄叉丙酮(3,4-dihydroxybenzylideneacetone,DHBAc)对SIRS模型小鼠的保护作用及机制。方法:BALB/c小鼠随机分为正常组,模型组,HBAc,DHBAc低、中、高剂量(25,50,100μg·kg~(-1))组。预防给药7 d后腹腔注射脂多糖(LPS),造模5 h后检测小鼠肛温、呼吸频率、白细胞、血小板计数、白细胞分类、糖脂代谢以及肺组织炎症因子和炎症相关蛋白磷酸化情况。结果:与正常组比较,模型组小鼠腹腔注射LPS(6 mg·kg~(-1))可致小鼠呼吸频率降低(P0.05),体温明显降低(P0.01),外周血白细胞数和单核细胞百分比增加(P0.01),血小板减少(P0.01),血糖水平降低(P0.05),肺组织中白细胞介素-1β分泌增多(P0.01)。与模型组比较,HBAc,DHBAc均明显增加动物呼吸频率,升高动物体温,降低外周白细胞水平以及单核细胞百分比(P0.05,P0.01),并显著升高血糖水平(P0.05,P0.01),减少肺组织中白细胞介素-1β的分泌(P0.01)。结论:腹腔注射LPS致小鼠SIRS模型成立,HBAc,DHBAc对LPS致小鼠SIRS模型有一定的保护作用,可能通过IκB,c-JUN通路发挥抗炎作用。  相似文献   
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目的:研究碘乙酸钠诱导的大鼠膝骨关节炎(KOA)模型肠道菌群变化情况,探究肠道菌群与KOA的潜在联系。方法:将SPF级大鼠分为空白对照组和KOA组,通过膝关节局部注射碘乙酸钠制造大鼠KOA模型。通过16SrDNA检测大鼠粪便中的肠道菌群变化情况,蛋白印记法检测结肠组织中NF-κB和TNF-α蛋白表达,RT-qPCR检测结肠组织中Caspase-1和IL-1β基因表达情况,苏木精-伊红染色观察结肠黏膜通透性变化,苏木精-伊红染色观察关节滑膜和软骨组织的病理变化情况。ELISA检测血液上清中LBP,IL-1β,TNF-α及IL-10炎症因子水平。结果:与空白对照组相比,从KOA组中筛选出明显变化的肠道菌群,以Akkermansia和疣微菌门变化最为显著,结肠黏膜通透性增加,结肠组织中NF-κB p65及TNF-α蛋白表达升高,结肠组织中Caspase-1和IL-1β基因表达升高,血液中促炎因子LBP,IL-1β及TNF-α蛋白含量升高,抗炎因子IL-10蛋白含量降低。结论:KOA病理状态下肠道菌群发生变化,结肠炎症反应增强,结肠炎症反应或许在提高全身炎症反应水平、促进与肠道菌群相关的KOA的病理进程中起到重要的桥梁作用。  相似文献   
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目的:探讨银杏内酯B(ginkgolide B,GB)对肌萎缩侧索硬化细胞模型c-Jun氨基末端激酶(JNK)信号通路及细胞凋亡的影响。方法:通过含过表达人突变超氧化物歧化酶1(SOD1)~(G93A)基因(hSOD1~(G93A))和过表达人野生SODWT基因(hSOD1WT)与空质粒的慢病毒感染NSC34细胞,经一定浓度的嘌呤霉素筛选,倒置荧光显微镜下观察慢病毒的转染效率和细胞形态的变化,蛋白免疫印迹法(Western blot)检验感染细胞是否过表达SOD1蛋白,建立hSOD1~(G93A)-NSC34细胞系后给予GB,细胞培养分组为正常组、模型组、不同浓度GB组(25,50,75,100 mg·L-1)组,48 h后噻唑蓝(MTT)比色法检测细胞存活率,筛选出最佳药物浓度,后续实验分组为以正常组,模型组,75 mg?L~(-1) GB组,SP600125组,75 mg?L-1GB+SP600125组,流式细胞术检测各组细胞的凋亡率,蛋白免疫印迹法(Western blot)检测磷酸化(p-)JNK,c-Jun,p-c-Jun,半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)蛋白的表达。结果:与正常的NSC34细胞比较,hSOD1~(G93A)NSC34组细胞胞体变圆,突触减少、变短,而hSOD1WT NSC34组细胞和空质粒组细胞形态学未发生明显变化,与正常组比较,hSOD1~(G93A)NSC34组,hSOD1WTNSC3组细胞内SOD1蛋白水平显著升高(P0. 01),肌萎缩侧索硬化(ALS)细胞模型成功建立。与正常组比较,模型组细胞存活率显著降低(P0. 01);与模型组比较,给予不同浓度GB后,细胞存活率均显著升高(P0. 01),药物质量浓度为75 mg?L-1时细胞存活率显著升高(P0. 01)。后续实验,与正常组比较,模型组凋亡率,p-JNK,p-c-Jun,cleaved Caspase-3蛋白表达量显著升高(P0. 01);与模型组比较,75 mg?L-1GB组,SP600125组,75 mg?L-1GB+SP600125组凋亡率,p-JNK,p-c-Jun,cleaved Caspase-3蛋白表达明显降低(P0. 05,P0. 01)。结论:GB对肌萎缩侧索硬化细胞模型具有抑制细胞凋亡的保护作用,这种保护作用可能是通过JNK信号通路实现的。  相似文献   
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