高压氧对脑损伤大鼠BDNF表达的影响

目的研究高压氧（HBO）治疗对侧位液压冲击脑损伤大鼠大脑皮层及海马区脑源性神经营养因子（BDNF）表达的影响。方法应用液压撞击仪制作侧位液压冲击脑损伤大鼠模型。Wistar雄性大鼠32只,随机分成脑损伤组及正常对照组,每组16只。各组再分别分为两组进行HBO暴露及常压空气暴露,每组8只。5 d后断头取脑,行脑组织切片,应用免疫组化方法检测BDNF在皮层及海马区的表达。结果正常对照组HBO暴露与常压空气暴露BDNF免疫阳性细胞数比较差异无统计学意义（P〉0.05）;脑损伤组中HBO暴露后皮层及海马BDNF免疫阳性细胞数多于常压空气暴露（P〈0.01）,脑损伤常压空气暴露组多于正常对照常压空气暴露组（P〈0.01）。结论大鼠脑损伤后可以提高损伤皮层及海马区BDNF的表达,HBO治疗可以进一步提高大鼠脑内BNDF的表达。     

组蛋白去乙酰化酶抑制剂联合芬维A胺诱导人肝癌细胞凋亡的研究

目的探讨组蛋白去乙酰化酶抑制剂Scdptaid、TSA分别联合芬维A胺诱导人肝癌细胞凋亡作用。方法组蛋白去乙酰化酶抑制剂Scriptaid（10／zM）合芬维A胺（10／zM）、TSA（1／zM）联合芬维A胺（10／zM）分别处理人肝癌细胞株（SNU475。SNU449,SNU398,sK—HEP-1,PLC／PRF／5）。通过Caspase-3／7检测试剂盒和CellTiter—Glo发光细胞活力检测试剂盒监测组蛋白乙酰化酶抑制剂联合芬维A胺对肝癌细胞的影响。结果组蛋白去乙酰化酶抑制剂Scriptaid（10／zM）、Ts（1／zM）联合芬维A胺（10肚M）处理细胞24h能显著诱导人肝癌细胞株SNU475、SNU449、SNU389、SK—HEP-1、PLC／PRF／5凋亡（P〈0．01）。结论组蛋白乙酰化酶抑制剂Scriptaid、TSA联合芬维A胺能诱导肝癌细胞凋亡。     

葡萄糖酸镁对离体大鼠心肌缺血再灌注细胞凋亡的影响

Objective To observe the protective effect of magnesium gluconate on myocardial apoptosis by ischemia reperfusion injury in isolated rat hearts, and study the possible mechanism. Methods The hearts of 48 Sprague-Dawely rats were isolated, linked to Lange-ndorff perfusion apparatus, and randomly divided into 3 equal groups(n = 16 each) : Control group, ischemia/reperfusion (I/R) group and magnesium gheonate group. 8 rats in each group were perfused. Control group was pedused with modified KH buffer for 110min. I/B group was perfuesd with modified KH buffer for 20 min, then exposed to iscbemia for 30 min, and then reperfused with modified KH buffer for 60 min. Magnesium gheonate group was perfumed with modified KH buffer with magnesium gluconate for 20 min, then exposed to isohemia for 30 min and then reperfused with modified KH buffer with magnesium glueonate for 60 min. Lacate dehydrogenase (LDH) and ereatine kinase (CK) in the effluent liquid from the heart were measured after reperfusion. The concentration of Ca2+ and NO in the left ventricle were determined. The other 8 rats in each group were reperfused for 120 minutes as the method described before. After repeffusion, the myoeyte apoptosis was examined by Annexin-V-FITC/PI. After the two experiments the incidence of ventrieular arrhytlunias during reperfusion was assessed. Results Compared with I/R, magnesium glueonate decreased the incidence of ventricular an'hythmias(P <0. 01). The contents of CK and LDH in the effluent liquid from the heart in magnesium glueonate group was lower than that of I/R group (P <0. 01). The contents of Ca2+ and NO in the left ventricle in magnesium gluconate group was decreased than that of I/R group (P <0. 01). The index of myocyte apoptosis were significanfly lower in magnesium glueonate group than that of I/R group (apoptosis index :27.79±1.59 vs 33.61±2.10, P < 0. 01) . Conclusion Magnesium glueonate has protective effect on myocardial isohemia reperfusion injury in rats. The protective effect may be related to decreasing myocyte apoptosis by increasing the content of NO and relieving calcium overload.     

2008年-2009年鞍山地区手足口病患儿粪便样本中肠道病毒的检测结果分析

目的:通过实时荧光RT-PCR法检测2008年-2009年手足口病患儿粪便样本,了解鞍山地区手足口病病原特征,为手足口病防治工作提供科学依据。方法:分别于2008年6月-9月收集657份手足口病患儿粪便样本及2009年5月-9月收集274份手足口病患儿粪便样本进行检测。结果:2008年EV71阳性31份,CA16阳性58份2,009年EV71阳性75份,CA16阳性55份。结论:鞍山地区手足口病病原体以EV71和CA16为主,2008年以CA16为主要病原,2009年以EV71为主要病原。重症手足口病患儿病原均为EV71。     

四维盆底超声在电刺激联合生物反馈结合盆底肌锻炼治疗压力性尿失禁疗效评估中的价值

目的:探讨四维盆底超声在电刺激联合生物反馈盆底肌锻炼治疗压力性尿失禁(SUI)疗效评估中的价值.方法:选择60例SUI患者,电刺激联合生物反馈盆底肌锻炼3个月后分析治疗效果;并于治疗前后采用经会阴四维盆底超声记录患者肛提肌裂孔面积、裂孔左右径、肛提肌厚度、膀胱颈移动度、膀胱尿道后角及尿道内口漏斗形成率.结果:治疗后,肛...     

急性肺损伤新生大鼠AQP5及CC16变化的临床意义

目的探讨肺组织水通道蛋白5（AQP5）、血及肺灌洗液Clara细胞蛋白（CC16）在急性肺损伤早期的动态改变及临床意义。方法将140只sD新生大鼠随机分两批（每批70只）,再随机分为正常对照组（NS组）及内毒素（LPS）组（LPS组,7个亚组）。LPS组予腹腔注射5mg／kgLPS制作新生大鼠急性肺损伤（ALI）模型。各亚组分别在注射后0．5、1、2、4、8、16h和24h处死后取材,第一批收集肺行组织病理和肺湿／干重比值检测,采集血清和支气管肺泡灌洗液（BALF）,用双抗体夹心ELISA法检测CC16含量。第二批取肺组织,用免疫印迹法测肺组织AQP5的表达,观察其动态改变。结果 ①LPS注射0．5h后在病理上动物出现点状肺出血,随时间推延渐发展为片状肺出血;LPS2h、4h组肺湿／干重比（W／D）明显增高,P〈0．01有统计学意义;②LPS0．5h组大鼠肺组织AQP5表达开始下调,1-2h组达到最低,继而AQP5表达渐上升,8h组与正常水平接近,之后再次下调至24h。③LPS致伤后大鼠BALF中CC16水平迅速下降,LPS组各组均较对照组有显著性差异（P〈0．01）;LPS组血清CC16水平较对照组上升,从注射LPS2h后开始有差异,4h达高峰,以后呈下降趋势,但8h、16h组仍明显高于对照组（P〈0．01）。结论①新生大鼠AQP5、CC16的改变反映了I型肺泡上皮细胞受损及Clara细胞损伤,三者可作为早期反映AU的敏感实验室指标。②LPS组AQP5、BALF及血清CC16与对照组有差异的时间点有差别,早期发现干预ALI对前两者监测更好。③AQP5表达变化提示可能存在治疗窗口期。     

Short-Term Visual Experience Leads to Potentiation of Spontaneous Activity in Mouse Superior Colliculus

Spontaneous activity in the brain maintains an internal structured pattern that reflects the external environment,which is essential for processing information and developing perception and cognition.An essential prerequisite of spontaneous activity for perception is the ability to reverberate external information,such as by potentiation.Yet its role in the processing of potentiation in mouse superior colliculus(SC)neurons is less studied.Here,we used electrophysiological recording,optogenetics,and drug infusion methods to investigate the mechanism of potentiation in SC neurons.We found that visual experience potentiated SC neurons several minutes later in different developmental stages,and the similarity between spontaneous and visually-evoked activity increased with age.Before eye-opening,activation of retinal ganglion cells that expressed ChR2 also induced the potentiation of spontaneous activity in the mouse SC.Potentiation was dependenton stimulus number and showed feature selectivity for direction and orientation.Optogenetic activation of parvalbumin neurons in the SC attenuated the potentiation induced by visual experience.Furthermore,potentiation in SC neurons was blocked by inhibiting the glutamate transporter GLT1.These results indicated that the potentiation induced by a visual stimulus might play a key role in shaping the internal representation of the environment,and serves as a carrier for short-term memory consolidation.     

Abnormal Micronutrient Intake Is Associated with the Risk of Periodontitis: A Dose–response Association Study Based on NHANES 2009–2014

The association between micronutrient intake and the risk of periodontitis has received much attention in recent years. However, most studies focused on the linear relationship between them. This study aimed to explore the dose–response association between micronutrient intake and periodontitis. A total of 8959 participants who underwent a periodontal examination, and reported their micronutrient intake levels were derived from the US National Health and Nutrition Examination Survey (NHANES, 2009–2014) database. Logistic regression was performed to evaluate associations between micronutrient intake and periodontitis after propensity score matching (PSM), and restricted cubic splines (RCS) analysis was conducted to explore the dose–response associations. Following PSM, 5530 participants were included in the RCS analysis. The risk of periodontitis was reduced with sufficient intake of the following micronutrients: vitamin A, vitamin B1, vitamin B2, and vitamin E. In addition, the risk of periodontitis was increased with excessive intake of the following micronutrients: vitamin B1 (1.8 mg/day, males; 1.3 mg/day, females), vitamin C (90 mg/day, males), and copper (1.1 mg/day, combined). In conclusion, a linear association was found between vitamin A, vitamin B2, vitamin C, and copper and periodontitis—namely, a sufficient intake of vitamin A and vitamin B2 might help reduce the prevalence of periodontitis; by contrast, a high intake of vitamin C and copper increased the risk. In addition, a nonlinear dose–response association was found for the incidence of periodontitis with vitamin B1 and vitamin E. When within reasonable limits, supplemental intake helped reduce the prevalence of periodontitis, while excessive intake did not help significantly and might even increase the risk. However, confounding factors, such as health awareness, should still be considered.     

唐以前山茱萸应用探析

通过梳理现存唐以前医书中应用山茱萸的方剂,结合历代本草文献对山茱萸的记载,分析唐以前医家应用山茱萸治疗疾病的特点,为现代临床应用山茱萸提供理论指导.山茱萸用治风邪,取补肝体、温肝阳之用;补诸虚,取其酸涩敛固、助壬癸蛰藏之功;治脚气,取其温中养血、逐寒湿痹之能;治耳聋,取其秘精气、通九窍之力;治其他病证,各取滋肾养阴、敛...     

Dromedary camel nanobodies broadly neutralize SARS-CoV-2 variants

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike is a trimer of S1/S2 heterodimers with three receptor-binding domains (RBDs) at the S1 subunit for human angiotensin-converting enzyme 2 (hACE2). Due to their small size, nanobodies can recognize protein cavities that are not accessible to conventional antibodies. To isolate high-affinity nanobodies, large libraries with great diversity are highly desirable. Dromedary camels (Camelus dromedarius) are natural reservoirs of coronaviruses like Middle East respiratory syndrome CoV (MERS-CoV) that are transmitted to humans. Here, we built large dromedary camel V_HH phage libraries to isolate nanobodies that broadly neutralize SARS-CoV-2 variants. We isolated two V_HH nanobodies, NCI-CoV-7A3 (7A3) and NCI-CoV-8A2 (8A2), which have a high affinity for the RBD via targeting nonoverlapping epitopes and show broad neutralization activity against SARS-CoV-2 and its emerging variants of concern. Cryoelectron microscopy (cryo-EM) complex structures revealed that 8A2 binds the RBD in its up mode with a long CDR3 loop directly involved in the ACE2 binding residues and that 7A3 targets a deeply buried region that uniquely extends from the S1 subunit to the apex of the S2 subunit regardless of the conformational state of the RBD. At a dose of ≥5 mg/kg, 7A3 efficiently protected transgenic mice expressing hACE2 from the lethal challenge of variants B.1.351 or B.1.617.2, suggesting its therapeutic use against COVID-19 variants. The dromedary camel V_HH phage libraries could be helpful as a unique platform ready for quickly isolating potent nanobodies against future emerging viruses.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of COVID-19 (1, 2) that enters human cells by binding its envelope anchored type I fusion protein (spike) to angiotensin-converting enzyme 2 (ACE2) (3, 4). The SARS-CoV-2 spike is a trimer of S1/S2 heterodimers with three ACE2 receptor-binding domains (RBDs) attached to the distal end of the spike via a hinge region that allows conformational flexibility (4). In the all-down conformation, the RBDs are packed with their long axes contained in a plane perpendicular to the axis of symmetry of the trimer. Transition to the roughly perpendicular up conformation exposes the receptor-binding motif (RBM), located at the distal end of the RBD, which is sterically occluded in the down state. Numerous neutralizing antibodies targeting the spike, particularly its RBD, have been developed to treat COVID-19 using common strategies such as single B cell cloning, animal immunization, and phage display (5–9). Most vaccines, including those that are messenger RNA based, are designed to induce immunity against the spike or RBD (10–12). However, emerging SARS-CoV-2 variants such as D614G, B.1.1.7 (Alpha, United Kingdom), B.1.351 (Beta, South Africa), and P.1 (Gamma, Brazil) have exhibited increased resistance to neutralization by monoclonal antibodies or postvaccination sera elicited by the COVID-19 vaccines (13, 14). Monoclonal antibodies with Emergency Use Authorization for COVID-19 treatment partially (Casirivimab) or completely (Bamlanivimab) failed to inhibit the B.1.351 and P.1 variants. Similarly, these variants were less effectively inhibited by convalescent plasma and sera from individuals vaccinated with a COVID-19 vaccine (BNT162b2) (13). The B.1.617.2 (Delta, India) variant became the prevailing strain in many countries (15). Highly effective and broadly neutralizing antibody therapy is urgently demanded for COVID-19 patients.Due to their small size and unique conformations, camelid V_HH single-domain antibodies (also known as nanobodies) can recognize protein cavities that are not accessible to conventional antibodies (16). To isolate high-affinity nanobodies without a need for further affinity maturation, it is highly desirable to construct large nanobody libraries with great diversity. Dromedary camels have been found as potential natural reservoirs of Middle East respiratory syndrome CoV (MERS-CoV) (17). We speculated that dromedary camels would be an ideal source of neutralizing nanobodies against coronaviruses. In the present study, we built large camel V_HH single-domain antibody phage libraries with a diversity of over 10¹¹ from six dromedary camels (Camelus dromedarius), three males and three females, with ages ranging from 3 mo to 20 y. We used both the SARS-CoV-2 RBD and the stabilized spike ectodomain trimer protein as baits to conduct phage panning for nanobody screening. Among all the binders, we found NCI-CoV-7A3 (7A3), NCI-CoV-1B5 (1B5), NCI-CoV-8A2 (8A2), and NCI-CoV-2F7 (2F7) to be potent ACE2 blockers. In addition, these dromedary camel nanobodies displayed potent neutralization activity against the B.1.351 and B.1.1.7 variants and the original strain (Wuhan-Hu-1). The cryoelectron microscopy (cryo-EM) structure of the spike trimer protein complex with these V_HH nanobodies revealed two distinct nonoverlapping epitopes for neutralizing SARS-CoV-2. In particular, 7A3 recognizes a unique and deeply buried region that extends to the apex of the S2 subunit of the spike. Combined treatment with 7A3 and 8A2 shows more potent protection against various variants in culture and mice infected with the B.1.351 variant. Interestingly, 7A3 alone retains its neutralization activity against the lethal challenge of the B.1.617.2 variant in mice.