Mapping conformational changes on bispecific antigen-binding biotherapeutic by covalent labeling and mass spectrometry

Biotherapeutic's higher order structure(HOS)is a critical determinant of its functional properties and conformational relevance.Here,we evaluated two covalent labeling methods:diethylpyrocarbonate(DEPC)-labeling and fast photooxidation of proteins(FPOP),in conjunction with mass spectrometry(MS),to investigate structural modifications for the new class of immuno-oncological therapy known as bispecific antigen-binding biotherapeutics(BABB).The evaluated techniques unveiled subtle structural changes occurring at the amino acid residue level within the antigen-binding domain under both native and thermal stress conditions,which cannot be detected by conventional biophysical techniques,e.g.,near-ultraviolet circular dichroism(NUV-CD).The determined variations in labeling uptake under native and stress conditions,corroborated by binding assays,shed light on the binding effect,and highlighted the potential of covalent-labeling methods to effectively monitor conformational changes that ultimately influence the product quality.Our study provides a foundation for implementing the developed techniques in elucidating the inherent structural characteristics of novel therapeutics and their conformational stability.

右胸导联V_(4R)和V_(5R)对由右冠脉近段阻塞引起的急性ST段抬高型心肌梗死的诊断价值

目的与右冠脉阻塞关联的ST段抬高型右室心肌梗死,住院期死亡率高。本研究假设是:右胸导联(V4R和V5R导联)有助于发现ST段抬高型右室心肌梗死。1342例患者记录12导联加右胸导联心电图。结果右冠脉近段阻塞者,V4R和V5R导联常见有ST段抬高,同时伴有Ⅰ,aVL,V5和V6导联ST段压低;常规12导联心电图通常不能发现ST段抬高。结论对于急性冠脉综合征,提高对ST段抬高型心肌梗死诊断的敏感性,常规12导联附加右胸导联是一项简便的方法。

EASI3导联衍生的12导联心电图的应用研究

目的在亚洲人群中导出EASI导联和常规12导联心电图的转换系数和方程,比较亚洲人群与北美人群之间导联转换上的差异性,同时观察导联转换是否受年龄、性别、身高和体重的影响。方法627例受试者同步记录常规12导联心电图和EASI导联心电图。同时记录年龄、性别、身高和体重。结论在亚洲人群和北美人群之间,导联转换无显著性差异,年龄、性别、身高和体重对导联转换无显著影响。

正常人标准胸导联和Mason-Likar胸导联心电图波段定量比较

目的:对我国正常人群标准12导联(标准导联)和Mason-Likar导联系统所记录胸导联心电图的波段进行定量比较。方法:选择84例冠状动脉造影和心脏超声检查结果均正常者作为研究对象,其均接受标准导联加Mason-Likar导联心电图记录检查,观察2种导联系统胸导联心电图中以下测定值的相关性及差异,包括R波振幅、ORS波振幅、ST段值[J点(ST on)、J点后0.08 s(ST 80 ms)和终点(ST end)]、ST段斜率及T波振幅结果:标准导联与Mason-Likar导联系统所记录的胸导联心电图存在良好相关性,但也存在统计学差异(P<0.001)。与标准胸导联相比.Mason-Likar胸导联心电图差异包括部分导联QRS波振幅明显降低、ST段显著下移伴V_1～V_6导联T波振幅下降,V_1导联中各波段降低均较显著(p均<0.001);Mason-Likar各胸导联中ST段的降低幅度均超过同一导联QRS波和T波的幅度改变,以V_6导联变化最显著。平均体重指数(BMI)与V_1、V_3导联QRS波振幅的改变呈负相关;V_1、V_2导联ST80ms与T波振幅、QRS波振幅的改变呈正相关,结论:标准导联与Mason-Likar导联系统所记录心电图波段有一定差异。

急性下壁心肌梗死中梗死相关血管的心电图表现

目的:探讨心电图在判断下壁急性心肌梗死(AMI)中梗死相关血管(IRA)和预测患者住院期间心脏事件中的价值,方法:选择经冠状动脉造影确诊的下壁AMI患者163例.观察其心电图表现与冠状动脉造影、住院期间心脏事件的关系。结果:163例下壁AMI患者中,右冠状动脉(RCA)病变112例,左回旋支(LCX)病变51例。以RCA病变为主时,心电图表现为Ⅲ导联ST段抬高幅度>Ⅱ导联ST段抬高幅度、aVL导联ST段压低和aVR导联ST段抬高:LCX病变心电图多表现为Ⅲ导联ST段抬高幅度<Ⅱ导联ST段抬高幅度、aVL导联ST段抬高和aVR导联ST段压低Ⅲ导联ST段抬高幅度>Ⅱ导联ST段抬高幅度,则提示合并有心室AMI及缓慢性心律失常的发生率高于Ⅲ导联ST段抬高幅度<Ⅱ导联ST段抬高幅度者。结论:临床医师可通过心电图上的ST段移位对AMI患者的IRA作出初步判断,并评估其预后。

心率变异性新指标对左室功能的评定价值

目的在已知有心脏疾病并伴有左室收缩功能降低的患者中,评定心率变异性(HRV)频域分析新指标。方法病变组:66例左室收缩功能降低者;对照组:64例心脏结构功能正常且无严重冠脉狭窄者。用5min心电图测定心率变异性频域中极高频成分并生成新指标VHF指数(VHFI)。结果病变组VHFI显著高于对照组(19.17±13.35vs11.37±10.77,p<0.05);VHFI与左室收缩功能呈负相关(R=-0.612);以VHFI>15为阳性,VHFI<15为阴性,对于左室收缩功能降低的预测敏感性和特异性分别为57.58%和78.13%。结论VHFI可以作为有价值的指标,用于急诊快速评定左室功能。

Virtual ballistic impact testing of Kevlar soft armor:Predictive and validated finite element modeling of the V0-V100 probabilistic penetration response

This works presents the first fully validated and predictive capability to model the V_0-V_(100) probabilistic penetration response of a woven fabric using a yarn-level fabric finite element model. The V_0-V_(100) curve describes the probability of complete fabric penetration as a function of projectile impact velocity. The exemplar case considered in this paper comprises of a single-layer, fully-clamped, plain-weave Kevlar fabric impacted at the center by a 17-gr, 0.22 cal FSP or fragment-simulating projectile. Each warp and fill yarn in the fabric is individually modeled using 3 D finite elements and the virtual fabric microstructure is validated in detail against the experimental fabric microstructure. Material and testing sources of statistical variability including yarn strength and modulus, inter-yarn friction, precise projectile impact location, and projectile rotation are mapped into the finite element model. A series of impact simulations at varying projectile impact velocities is executed using LS-DYNA on the fabric models, with each model comprising unique mappings. The impact velocities together with the outcomes(penetration, nonpenetration) are used to generate the numerical V_0-V_(100) curve which is then validated against the experimental V_0-V_(100) curve. The numerical Vi-Vrdata(impact, residual velocities) is also validated against the experimental Vi-Vrdata. For completeness, this paper also reports the experimental characterization data and its statistical analysis used for model input, viz. the Kevlar yarn tensile strengths, moduli, and inter-yarn friction, and the experimental ballistic test data used for model validation.

Effects of ply orientation and material on the ballistic impact behavior of multilayer plain-weave aramid fabric targets

Virtual testing of fabric armor provides an efficient and inexpensive means of systematically studying the influence of various architectural and material parameters on the ballistic impact behavior of woven fabrics, before actual laboratory prototypes are woven and destructively tested. In this finite element study, the combined effects of individual ply orientations and material properties on the impact performance of multi-layered, non-stitched woven aramid fabrics are studied using 2-and 4-sided clamping configurations. Individual ply orientations of 0°, ±15°, ±30°, and ±45° are considered along with three levels of inter-yarn friction coefficient. Functionally graded fabric targets are also considered wherein the yarn stiffness progressively increases or decreases through the target thickness while keeping the yarn strain energy density constant and with all other material and architectural parameters unchanged for consistency. For each target configuration, one non-penetrating and one penetrating impact velocity is chosen. The impact performance is evaluated by the time taken to arrest the projectile and the backface deformation for the non-penetrating impacts, and by the residual velocity for the penetrating impact tests. All deterministic impact simulations are performed using LS-DYNA. 2-sided clamped targets and lower inter-yarn frictional levels generally resulted in better impact performance.The functionally graded targets generally showed either similar or inferior impact performance than the baseline fabric target configurations for the non-penetrating shots. Some performance improvements were observed for the penetrating shots when the yarn stiffness was progressively decreased through the layers in a direction away from the strike face, with additional performance enhancements achieved by simultaneously reducing the inter-yarn friction.

Role of macrophages and monocytes in hepatitis C virus infections

A number of studies conducted over many years have shown that hepatitis C virus(HCV)can infect a variety of cell types.In vivo infection of monocytes,macrophages,and dendritic cells by HCV has been frequently shown by a number of researchers.These studies have demonstrated replication of HCV by detecting the presence of both negative genomic strands and a variety of non-structural HCV proteins in infected cells.In addition,analyses of genome sequences have also shown that different cell types can harbor different HCV variants.Investigators have also done preliminary studies of which cellular genes are affected by HCV infection,but there have not yet been a sufficient number of these studies to understand the effects of infection on these cells.Analyses of in vitro HCV replication have shown that monocytes,macrophages and dendritic cells can be infected by HCV from patient sera or plasma.These studies suggest that entry and cellular locations may vary between different cell types.Some studies suggest that macrophages may preferentially allow HCV genotype 1 to replicate,but macrophages do not appear to select particular hypervariable regions.Overall,these studies agree with a model where monocytes and macrophages act as an amplification system,in which these cells are infected and show few cytopathic effects,but continuously produce HCV.This allows them to produce virus over an extended time and allows its spread to other cell types.

Art@Med专栏Ⅰ心脏的混沌

医生不仅是手术匠，也是音乐家与艺术家，在复杂的生理系统中寻找跳动的韵律；医生不仅是修理工，也是画家、诗人，在冰冷的培养基上寻找变幻的图案。脱下白大褂，医生还是儿女、父母……是个平凡而真实的人，在生活中寻找精神标杆，用感恩的心歌颂世间美好。AME在一群优秀医生中，发现了诗人、书法家、歌手、漫画家……因此，我们推出Art@Med专栏，带您踏上一场人文之旅，去挖掘医学的艺术，医生的诗意。

Balance Performance in Female Collegiate Athletes

Proper balance is essential for athletes during competition and training as sport places different balance requirements on the human body. The purpose of the study was to analyze balance performance among female athletes using COP （center of pressure） sway parameters. Twenty one NCAA （National Collegiate Athletic Association） division I female athletes （soccer, volleyball and dance） completed the study. Static balance was assessed using UST （unilateral stance test） and dynamic balance was assessed using MCT （motor control test） on the NeuroCom Equitest. Sway velocities, root mean square sway and reaction time latencies were used to quantify balance. A one-way between subjects ANOVA （analysis of variance） was performed to analyze these balance parameters. Significant （p 〈 0.05） differences between groups were found and post hoc comparisons revealed that the volleyball and dance groups had better static balance compared to soccer players, while both soccer and volleyball groups had better dynamic balance compared to the dance group. The results from the study indicate two points： first, differences in balance performance among female athletes in different sporting discipline; second, there is no relationship between static and dynamic balance. This indicates that it may be more beneficial to assess and train for static and dynamic balance individually.

Antibody responses in COVID-19 patients

Measuring virus-specific antibody responses to emerging pathogens is a well-established and highly useful tool to diagnose such infections,understand interactions between the immune system and pathogens,and provide potential clues for the development of vaccines or therapeutic agents against such pathogens.Since the beginning of 2020,the discovery of SARS-CoV-2 as the emerging virus responsible for the COVID-19 pandemic has provided new insight into the complexity of antibody responses to this dangerous virus.The current review aims to sort out diverse and sometimes seemingly confusing findings to put together a cohesive understanding on the profile of antibody responses elicited in COVID-19 patients.

On the fracture resistance of adhesively jointing structures

The interface toughness of adhesively bonded structural members is one of the critical parameters for adhesive joint design. It is often assumed that the joint toughness is a material constant so that its value can be obtained from fracture tests of simple geometries such as DCB for Mode-Ⅰ, ENF for Mode-Ⅱ, using linear elastic fracture mechanics （LEFM）. However, the LEFM assumption of point-wise crack-tip fracture process is overly simplistic and may cause significant error in interpreting fracture test data. In this paper, the accuracy and applicability of various traditional beam-bending-theory based methods for fracture toughness evaluation, such as simple beam theory （SBT）, corrected beam theory （CBT） and experimental compliance method （ECM）, were assessed using the cohesive zone modelling （CZM） approach. It was demonstrated that the fracture process zone （FPZ） size has profound influence on toughness calculation and unfortunately, all the classic beam-bending theories based methods fail to include this important element and are erroneous especially when the ratio of crack length to FPZ size is relatively small （〈5.0）. It has also been demonstrated that after the FPZ size is incorporated into simple beam formulations, they provide much improved evaluation for fracture toughness. Formulation of first order estimate of FPZ size is aIso given in this paper.

The Pattern and Cost of Palliative Surgeries in Patients with Metastatic Melanoma

Objective: To investigate the pattern of palliative surgeries and associated costs in patients with metastatic melanoma in the USA. Methods: This was a retrospective claims-based study of patients identified using administrative claims from MarketScan&reg?databases among patients with metastatic melanoma diagnosed between 2005 and 2011. Patient characteristics, patterns and cost of surgery, and length of hospital stay were evaluated. Results: Of the 2399 patients identified, 888 (37.0%) underwent at least one surgical procedure either in the outpatient or inpatient setting. The subgroup of patients who underwent surgery included significantly more patients with distant skin metastases compared to the subgroup who did not receive surgery;whereas significantly more patients in the non-surgery group had brain or bone metastases. Surgery performed in the outpatient setting was predominantly on the skin, whereas surgery on the brain was generally performed in the inpatient setting. The mean cost of the surgical procedures performed in the outpatient setting was $3393 (median: $1419) per procedure, which varied according to the location of the metastasis. For surgical procedures that were performed in the inpatient setting, the mean length of stay in hospital due to surgery was 4.4 (± 5.1) days, at a mean cost of $37,649 (median: $28,067) per hospitalization. Conclusions: Surgery is prevalent and costly in patients with metastatic melanoma.

Do Patients with Asymptomatic Congenital Complete Heart Block Require a Pacemaker for Non-Cardiac Surgery?

The appropriate preparation of the patient with asymptomatic congenital complete heart block (CCHB) and a narrow QRS complex for elective non-cardiac surgery is controversial. Prophylactic temporary pacemaker insertion is associated with well-defined risks, and less invasive techniques exist to treat transient, hemodynamically significant intraoperative brady-arrhythmias. The present case report details the performance of general anesthesia for arthroscopic knee surgery in an adult patient with this condition without a pacemaker. Documentation of preoperative chronotropic competence with isoproterenol may be of value in deciding whether to proceed without temporary pacing capability in this setting.

Hospital Costs of Adverse Events in Patients with Metastatic Colorectal Cancer

Background: Monoclonal antibody treatments for metastatic colorectal cancer (mCRC) have distinct treatment-related safety profiles. This study aimed to elucidate the hospitalisation costs of adverse events (AEs) commonly associated with monoclonal antibodies when administered to patients with mCRC. Methods: This study extracted data for patients newly diagnosed with mCRC from a large US claims database from January 2005 to June 2008. The first distant metastasis diagnosis date was defined as the index date. Main outcomes were length of hospital stay (days) and hospitalisation costs (2010 US$) for AEs (identified by primary discharge diagnoses). All analyses are presented descriptively. Results: The study population (aged ≥18 years;n = 12,648) was balanced according to gender and was mainly aged 50 years or older (90.1%). Most patients had colon cancer (70.1%) as opposed to rectal cancer. Gastrointestinal (GI) perforation incurred the longest median length of stay (11.5 days) for hospitalisations, followed by wound-healing complications (7 days), arterial and venous thromboembolism (5.5 and 4 days, respectively), and congestive heart failure (4 days). The highest inpatient cost per event was for GI perforations (mean $66,224 and median $ 34,027), followed by arterial thromboembolism ($40,992 and $18,587), wound-healing complications ($36,440 and $21,163), interstitial lung disease ($26,705 and $19,111) and acute myocardial infarction ($22,395 and $15,223). Skin toxicity (mean $6475 and median $6110) and hypertension ($14,108 and $6047) were associated with relatively low costs. Conclusions: Hospital costs for monoclonal antibody treatment-related AEs in patients with mCRC vary greatly. This study provides source data for economic evaluations of head-to-head comparisons of monoclonal antibody treatments.

Medical Costs by Disease Stage in Medicare Patients with Metastatic Melanoma

Background: Melanoma is a rare but serious skin cancer that is responsible for >90% of skin cancer-related deaths. This retrospective data analysis quantifies the direct cost of medical care by disease stage at diagnosis for patients with metastatic melanoma. Methods: The Surveillance, Epidemiology, and End Results (SEER)-Medicare database was queried for patients diagnosed between 2004-2009 with stage IIIB/C and stage IV (M1a, M1b, M1c) melanoma. The primary outcome was overall medical utilization and associated costs from diagnosis to death, the end of Medicare enrolment, or 12/31/2010. Results are stratified by disease stage at diagnosis and presented as per-patient per-month (PPPM) costs. Results: Of the 1263 patients meeting the study criteria (mean age: 75 years;64% male, 92% white, mean duration of follow up: 37.5 months), 66.6% were diagnosed at stage IIIB/C and 33.4% at stage IV. Cost of care increased with disease stage. Total PPPM costs ranged from $1966 for patients diagnosed with stage IIIB to $4585 among patients diagnosed with stage M1c. Outpatient costs accounted 48.9% of total medical costs among stage IIIB patients, and 38.7% of total medical costs for stage M1c patients. Inpatient costs accounted for 37.1% (stage M1b) - 40.9% (stage M1c) of total medical costs. Conclusions: Healthcare costs for treating patients with metastatic melanoma increase by disease stage. The cost of care was more than double among patients with late stage compared to those with early stage. Treatments demonstrating ability to prevent disease progression from early stage to late stage may confer an economic benefit among other clinical advantages.

Earthworms: A Source of Protein

Earthworms are important invertebrates that have been widely used as food and traditional medicine sources for thousands of years. Not only have researchers proven that earthworms are rich in proteins and other nutrients, they have also taken a keener interest in their unique pharmaceutical properties. Recent research has successfully discovered some beneficial functional components of earthworms due to the rapid development of biological technologies in the past decades. Therefore, earthworms could be a novel dietary supplement for human consumption. This review aims to summarize the current research about nutritional and therapeutic values of earthworms;and present a matured earthworm-derived product from Bocom Pharmaceuticals (USA) Corp as an example of its incorporation into a dietary supplement.

Fruit intake associated with urinary estrogen metabolites in healthy premenopausal women

Urinary concentrations of 2:16-hydroxyestrone (2:16-OHE1) approximate concentrations of 2-OHE1 and 16α-OHE1 in breast tissue. As estrogens are purported to be involved in breast cancer development, the 2:16-OHE1 ratio can provide an indication of estrogen metabolite exposure in the breast. With prior studies observing associations between urinary estrogen metabolites and dietary intakeof fruits, vegetables, and fiberascertained from food questionnaires, we examined associations between dietary factors ascertained through 3-day food records and urinary 2:16-OHE1 in191 pre-menopausal healthy women. Fruit consumption was positively associated with 2:16-OHE1 after adjustment for total energy, ethnicity, body mass index, parity, smoking history, and serum estradiol (p = 0.003). Fruit consumption was positively associated with 2-OHE1 concentrations (p = 0.006), but was not associated with 16α-OHE1 (p = 0.92). The Musaceae botanical grouping (comprised primarily of bananas) was positively associated with the 2:16-OHE1 ratio, and Rosaceae (comprised of citrus fruits) and Musaceae botanical groupings were positively associated with 2-OHE1 (but not 16α-OHE1) concentrations, after adjustment for confounders. Our data suggest that dietary fruit intakeis associated with urinary 2-OHE1 and the 2:16-OHE1 ratio and that breast tissue exposure to estrogen metabolites may thus be influenced-by diet.

抗高血压治疗期间心电图左心室肥厚消退及其对主要心血管事件的预测作用

背景：心电图左心室肥厚（left ventficular hypertophy，LVH）是心血管并发症及死亡的强预测指标。然而，在抗高血压治疗期间心电图LVH程度变化的预测价值仍不清楚。 目的：验证抗高血压治疗期间心电图LVH程度越轻，心血管并发症与死亡率越低，并与血压水平及其降低和治疗方式无关的假说。 设计、设置及参试者：1995～2001年于9193例55至80岁（均值，67岁）男性和女性高血压患者进行的双盲、随机、平行组研究。心电图LVH用康奈尔电压一时间乘积或Sokolow—Lyon电压表示，患者均入选氯沙坦降低高血压终点事件干预研究（Losartan Intervention For Endpoint，LIFE）。 干预：以氯沙坦或阿替洛尔为基础的治疗方案，随访评估至少4年（均值，4．8年[SD，0．9]）。主要结果测定：心血管死亡、心肌梗死或卒中复合终点与基线及随后1年或每年心电图LVH严重程度的关系。 结果：1096例（11．9％）发生心血管死亡、非致死性心肌梗死或卒中。在控制治疗方式、基线Framingham危险记分、基线和治疗期间血压以及基线心电图LVH严重程度（康奈尔乘积或Sokolow—Lyon电压）的Cox回归模型中，康奈尔乘积和Sokolow—Lyon电压所示治疗中LVH严重程度较低者，复合心血管终点事件的发生率分别降低14％和17％（康奈尔乘积每降低1050mm×ms,[1-SD]：校正风险比[hazard ratio，HR]，0．86；95％可信区间[confidence interval，CI]，0．82～0．92；P〈0．001；Sokolow—Lyon电压每降低10．5mm[1-SD]：HR，0．83；95％CI，0．78～0．88；P〈0．01）。在平行分析中，较低的康奈尔乘积和Sokolow—Lyon电压均与较低的心血管死亡（分别为HR，0．78；95％CI，0．73～0．83；P〈0．001和HR，0．80；95％CI，0．73～0．87；P〈0．001）、心肌梗死（HR，0．90；95％CI，0．82～0．98；P=0．01和HR，0．90；95％CI，0．81～1．00；P=0．04））和卒中（HR，0．90；95％CI，0．84～0．96；P=0．002；HR，0．81；95％CI，0．75～0．89；P〈0．001）独立相关。 结论：抗高血压治疗期间，根据康奈尔乘积和Sokolow—Lyon电压判定的心电图LVH程度较轻与心血管并发症和死亡可能性较低相关，而且独立于原发性高血压患者的血压降低及治疗方式。旨在改善或预防心电图LVH的抗高血压治疗可以改善患者的预后。