Brain Activation for Knee Movement Measured Days Before Second Anterior Cruciate Ligament Injury: Neuroimaging in Musculoskeletal Medicine

BackgroundAnterior cruciate ligament (ACL) injury has multifactorial causes encompassing mechanical, hormonal, exposure, and anatomical factors. Alterations in the central nervous system also play a role, but their influence after injury, recovery, and recurrent injury remain unknown. Modern neuroimaging techniques can be used to elucidate the underlying functional and structural alterations of the brain that predicate the neuromuscular control adaptations associated with ACL injury. This knowledge will further our understanding of the neural adaptations after ACL injury and rehabilitation and in relation to injury risk. In this paper, we describe the measurement of brain activation during knee extension-flexion after ACL injury and reconstruction and 26 days before a contralateral ACL injury.MethodsBrain functional magnetic resonance imaging data for an ACL-injured participant and a matched control participant were collected and contrasted.ResultsRelative to the matched control participant, the ACL-injured participant exhibited increased activation of motor-planning, sensory-processing, and visual-motor control areas. A similar activation pattern was present for the contralateral knee that sustained a subsequent injury.ConclusionsBilateral neuroplasticity after ACL injury may contribute to the risk of second injury, or aspects of neurophysiology may be predisposing factors to primary injury.

Clinical Implications

Sensory-visual-motor function and motor-learning adaptations may provide targets for rehabilitation.Key Words: neuroplasticity, functional magnetic resonance imaging, motor control

Key Points

• After anterior cruciate ligament reconstruction, rehabilitation, and return to play, neurologic differences in knee motor control may persist.
• Anterior cruciate ligament injury and recovery may induce specific changes in brain processing regarding sensory-visual-motor integration.

Individuals who experience a primary anterior cruciate ligament (ACL) injury and return to sport may have up to a 25% chance of experiencing a second ACL injury to either knee, despite surgical reconstruction and rehabilitation.^1,2 The contralateral knee may be at greater risk of injury than the involved knee,² suggesting possible postinjury bilateral neurologic alterations or the presence of bilateral factors that contributed to the initial injury.³ Researchers have reported that these postinjury neurologic differences include disrupted central nervous system afferent function,^4,5 altered efferent output,^3,6 and changes in brain activity for motor control.^7,8Few investigators have prospectively studied the neurologic changes that occur in the brain after ACL injury, reconstruction, and rehabilitation and before subsequent injury. Therefore, the purpose of this paper was to describe the brain activation for knee motor control measured after initial ACL reconstruction (ACLR) and 3 weeks before a contralateral ACL injury. We hypothesized that the ACLR participant would have greater motor-planning and sensory-area activation than a healthy matched control participant. This postinjury neuroplasticity or predisposing neurologic function may help to explain the underlying mechanisms contributing to prolonged deficits in neuromuscular control after ACL injury.⁹     

眼前节组织OCT图像角膜中央厚度测量

目的:光相干层析技术(OCT)是近来发展起来的成像技术,而眼前节组织OCT图像生物测量技术在OCT设备国产化、打破此类医学设备的国外技术垄断,是急需解决的问题.方法:提出一种两步法解决SL-OCT图像角膜中央厚度测量问题,第一步粗定位,首先采用灰度阈值分割角膜OCT图像,利用一维的中值滤波对轮廓进行平滑,从而粗定位角膜的内外轮廓:第二精定位,采用三次曲线及最小二乘法分段拟合角膜中央的内外轮廓,得到精确的角膜中央轮廓.根据轮廓坐标求取角膜中央厚度,算法使用VC++6.0编程实现.结果:对16例角膜OCT图像分别利用文中算法测量与ZEISS VISANTETM软件测量,对两种方法的测量结果运用配对t检验进行比较,对两组的个体重复测量的变异性采用变异系数,组内相关系数进行研究,配对t检验认为所用算法的测量结果与ZEISS VISANTETM性软件的测量结果一致,其结果的变异系数较小,组内的相关系数较大,具有较好的重复性.结论:所研究的算法可为国产的OCT设备的图像分析系统提供了一种测量功能,较好的精度,为开发具有自主知识产权的OCT成像仪打下一定的基础.     

The Third Eye of the Rheumatologist: Applications of Musculoskeletal Ultrasound in Rheumatic Diseases

Rheumatologists manage patients with rheumatic diseases, which are of a wide range of musculoskeletal pathologies. Without clarification of the exact location of pathologies and the degree of inflammation, rheumatologists may have an incorrect assessment, leading to inappropriate management. In everyday practice, physical examination is limited by its sensitivity and power of assessment. Musculoskeletal ultrasonography (MSUS) is inexpensive, readily available, and allows side-by-side image comparisons. Thus, during the past 10 years, MSUS has become the “third eye” of the rheumatologist, in that it allows more detailed examination of muscles, bones, and joints, just as the stethoscope provides further details about the respiratory and circulatory systems. We briefly introduce how rheumatologists in Taiwan use MSUS for the diagnosis and treatment for rheumatic diseases.     

Specific Unresponsiveness to Coryneracterium Parvum as Measured by Delated Hypersensitivity

In order to induce specific unresponsiveness to C. parvum mice were given seven daily i.v./i.p. injections of a high dose of the vaccine, or were given a single i.v. injection of C. parvum followed by an i.p. injection of cyclophosphamide (CY). Mice given the high-dose procedure had a significant level of residual footpad reactivity to C. parvum challenge, but subsequent sensitizing injections did not stimulate delayed hypersensitivity (DH). In contrast, mice given C. parvum and CY did not respond to challenge, and they could not be sensitised to C. parvum. Their unresponsiveness was sntlgenically specific and was stable for at least six weeks. Antibodies to C. parvum were Induced by both pretreataant procedures. This is the first report of the production of mice specifically unable to mount DH to a bacterial immune stimulant.     

Specific Unresponsiveness to Coryneracterium Parvum as Measured by Delated Hypersensitivity

In order to induce specific unresponsiveness to C. parvum mice were given seven daily i.v./i.p. injections of a high dose of the vaccine, or were given a single i.v. injection of C. parvum followed by an i.p. injection of cyclophosphamide (CY). Mice given the high-dose procedure had a significant level of residual footpad reactivity to C. parvum challenge, but subsequent sensitizing injections did not stimulate delayed hypersensitivity (DH). In contrast, mice given C. parvum and CY did not respond to challenge, and they could not be sensitised to C. parvum. Their unresponsiveness was sntlgenically specific and was stable for at least six weeks. Antibodies to C. parvum were Induced by both pretreataant procedures. This is the first report of the production of mice specifically unable to mount DH to a bacterial immune stimulant.     

EGG Hypersensitivity as Measured by RAST and a Reverse Enzyme-Immunoassay

The application of a reverse enzyme-immunoassay (REIA) to measure specific anti-egg IgE is described. The results obtained with the REIA and the RAST are shown. The REIA is economical, easy and fast to perform when the conjugate has been made, non-radioactive and offers a new alternative for the in vitro evaluation of egg white-specific IgE.     

Assessment of the Anterior Talofibular Ligament Thickness in Patients with Chronic Stroke: An Ultrasonographic Study

Background

Patients with equinovarus deformity have an increased risk of fall and ankle ligament injury, because of inappropriate prepositioning of the ankle at the end of the swing phase, and inadequate leg and ankle stability during the stance phase. Accordingly, the aim of this study is to compare anterior talofibular ligament (ATFL) thickness of chronic stroke patients with that of healthy individuals using ultrasonography.

Sleep Health as Measured by RU SATED: A Psychometric Evaluation

ABSTRACT

Objective/Background: Sleep health is a multidimensional construct of sleep and wakefulness that operationalizes optimal sleep as more than the absence disease. Despite its importance to public health promotion efforts, empirical research examining sleep health is currently limited, possibly due to the lack of empirically validated measures. Therefore, the purpose of the current study was to evaluate the psychometric properties of a previously proposed six-item sleep health scale (RU- SATED).

Participants: A sample of 3,401 adults (Mean Age = 42.77, 47.8% female) completed an online survey of sleep and health.

Methods: Participants completed the RU-SATED scale, as well as other sleep-related measures including the Insomnia Severity Index (ISI) and the Sleep Self-Efficacy Scale (SSE).

Results: An exploratory factor analysis (EFA) revealed a two-factor structure. A confirmatory factor analysis (CFA) using this two-factor structure demonstrated adequate to good model fit indices (X ² = 45.96, df = 8, p < .01; RMSEA = .04; CFI = .98; NFI = .98; TLI = .97). Cronbach’s α was .64 and the average interitem correlation was .22. RU-SATED was negatively associated with insomnia severity and positively associated with both self-reported sleep and sleep self-efficacy.

Conclusions: RU-SATED appears to be a valid instrument for the assessment of sleep health among adults that is related to, but distinct from, other established sleep constructs. Future research may benefit from examining the test–retest reliability of the measure and assessing the predictive validity of sleep health as it relates to health-related outcomes.     

MTT检测超声激活血卟啉对SW-480细胞的杀伤作用

本实验采用1.1、1.6、2.3MHz频率聚焦超声结合血卟啉的方式对体外培养的人结肠癌细胞SW-480进行照射,其介质分别为NaCl溶液、PRMI1640、完全培养基,并采用MTT法测试SDT对肿瘤细胞的杀伤效果。结果表明:SW-480细胞在声照强度为1.5W/cm2 ,频率2.3 MHz条件下,介质为NaCl溶液、PRMI1640和完全培养基中都存在超声激活血卟啉增强杀伤肿瘤细胞的效果,且在PRMI1640和完全培养基中这种效果和处理后细胞孵育的时间有一定的相关性。     

Heparin in Clinical Doses 'Primes' Granulocytes to Subsequent Activation as Measured by Myeloperoxidase Release

The author pre-incubated isolated human granulocytes with increasing doses of heparin (0–100 IU/mL) before subsequent stimulation with formyl-met-leu-phe. There was a dose-dependant increase in granulocyte activation as measured by myeloperoxidase release, quantitated in enzyme-immunoassay. This 'priming' effect of heparin was not due to activation of contaminating platelets or to endotoxin, and there was no reduction in granulocyte viability. Heparin-induced 'priming' of granulocytes may be clinically relevant in the setting of cardiopulmonary bypass. The author describes a sensitive and specific double antibody enzyme-immunoassay for myeloperoxidase from human granulocytes, with an inter-assay coefficient of variation of 12.6%, an intra-assay coefficient of variation of 4.3%, and a lower detection limit of 1.8 μg/l.     

Sex Differences in Brain Maturation as Measured Using Event-Related Potentials

Little is known about how sex influences functional brain maturation. The current study investigated sex differences in the maturation of event-related potential (ERP) amplitudes during an auditory oddball task (N = 170; age = 6–17 years). Performance improved with age. N200 amplitude declined with age: parietal sites showed earlier development than temporal and frontal locations. Girls showed greater bilateral frontal P300 amplitude development, approaching the higher values observed in boys during childhood. After controlling for age, right frontal P300 amplitude was associated with reaction time in girls. The findings demonstrate sex differences in ERP maturation in line with behavioral and neuroimaging studies.     

Stability of Human Immunodeficiency Virus RNA in Blood Specimens as Measured by a Commercial PCR-Based Assay

We investigated the effects of conditions often encountered during handling, transit, and storage of blood specimens on the quantity of detectable human immunodeficiency virus (HIV) RNA in plasma. HIV RNA copy numbers were measured with a commercially available assay (the Amplicor HIV-1 Monitor test kit). Variables examined were the time to processing of blood and plasma, the holding temperature of blood and plasma prior to processing, the effect of freezing and thawing of plasma, and the use of different anticoagulants. The relationship between the HIV RNA copy number and the HIV isolation rate by peripheral blood mononuclear cell (PBMC) coculture was also examined. We found that RNA copy numbers were maintained to within 0.5 log₁₀ (approximately threefold) in blood and plasma samples held at room temperature or 4°C for up to 3 days and remained stable despite (limited) freezing and thawing of the plasma. HIV RNA copy numbers were also maintained after long-term storage of plasma at −70°C. The ability to isolate HIV from PBMCs was directly proportional to the HIV RNA copy number.     

Functional Status as Measured by Geriatric Assessment Predicts Inferior Survival in Older Allogeneic Hematopoietic Cell Transplantation Recipients

Allogeneic hematopoietic cell transplantation (alloHCT) has been increasingly offered to older adults with hematologic malignancies. However, optimal methods to determine fitness for alloHCT have yet to be defined. We evaluated the ability of a comprehensive geriatric assessment (CGA) to predict post-alloHCT outcomes in a single-center prospective cohort study of patients age 50 years and older. Outcomes included overall survival (OS), progression-free survival (PFS), and nonrelapse mortality (NRM). A total of 148 patients were included, with a median age of 62 years (range, 50 to 76 years). In multivariate regression analysis, several CGA measures of functional status were predictive of post-alloHCT outcomes, after adjusting for traditional prognostic factors. Any deficit in instrumental activities of daily living (IADL) was associated with inferior OS (hazard ratio [HR], 1.81, 95% confidence interval [CI], 1.07 to 3.08; P = .03) and PFS (HR, 1.85; 95% CI, 1.15 to 2.99; P = .01). A Medical Outcomes Study Physical Health scale (MOS-PH) score <85 was associated with inferior OS (HR, 1.96; 95% CI, 1.13 to 3.40; P = .02), PFS (HR, 1.75; 95% CI, 1.07 to 2.88; P = .03), and increased NRM (subdistribution HR, 2.57; 95% CI, 1.12 to 5.92; P = .03). MOS-PH score was also associated with the number of non-hematologic grade ≥3 adverse events within the first 100 days after alloHCT (rate ratio, 1.61; 95% CI, 1.04 to 2.49; P = .03). These findings support previous work suggesting that IADL is an important prognostic tool prior to alloHCT. MOS-PH is newly identified as an additional metric to identify older patients at higher risk of poor post-alloHCT outcomes, including toxicity and NRM.     

Differentiation of T Lymphocytes in the Human Adenoid as Measured by the Expression of CD45 Isoforms

Encounter of antigen by T lymphocyte on antigen-presenting cells results in changes in the expression of several cell surface molecules, including the abundant cell surface glycoprotein CD45. We have characterized the expression of the CD45 isoforms CD45RA and CD45RO in CD4⁺ and CD8⁺ T lymphocytes in the adenoids and peripheral blood of young children. We found that the relative proportions of CD45RA⁻,CD45RO⁺ antigen-experienced T cells was higher in the adenoids than in peripheral blood, and that the proportion of naive or resting CD45RA⁺,CD45RO⁻ T cells was lower in the adenoids than in peripheral blood. The frequency of bright double-positive CD45RA⁺,CD45RO⁺ T cells, which represent cells in transition from the CD45RA⁺ to CD45RO⁺ phenotype, was higher in the adenoids than in peripheral blood. The frequency of another double-positive cell population, but with unknown ontogeny, expressing both CD45RA and CD45RO at a low level, was higher in peripheral blood than in adenoidal T cells. It was found that the frequency of adenoidal antigen-experienced CD45RA⁻,CD45RO⁺ T lymphocytes increased with increasing age of the child. These results are consistent with the model that the adenoids serve as a site for conversion of CD45RA⁺ to CD45RO⁺ T lymphocytes, and that the maturation of the immune system in young children is associated with phenotypic changes in T lymphocytes residing in secondary lymphoid organs.     

Balance Recovers Within 20 Minutes After Exertion as Measured by the Balance Error Scoring System

OBJECTIVE: To determine a balance recovery timeline after a functional exertion protocol using the Balance Error Scoring System (BESS). DESIGN AND SETTING: Five subject groups (4 test, 1 control) were tested 3 times during 1 session: once before the exertion protocol (pretest) and twice after the exertion protocol (posttest I and posttest II). Posttest I occurred at staggered intervals of 0, 5, 10, and 15 minutes, depending on experimental group assignment, and posttest II occurred at 20 minutes. SUBJECTS: One hundred subjects (80 test, 20 control) volunteered to participate in this study. None of the subjects had a balance disorder, mild head injury, or lower extremity injury in the 6 months before testing. MEASUREMENTS: We assessed balance using the BESS, assigning a score for each stance-surface condition. RESULTS: We found a significant decrease in BESS performance after the exertion protocol in all test groups, with exertion having the greatest effect on the tandem and single-leg stance conditions. All subjects recovered by posttest II, which was administered 20 minutes after cessation of the exertion protocol. CONCLUSIONS: Athletic trainers need to be aware of the effect of exertion when administering the BESS after physical activity. Athletic trainers can expect the BESS performance of healthy athletes to return to baseline levels within 20 minutes of rest.     

Molecular Interactions between the HSV-1 Capsid Proteins as Measured by the Yeast Two-Hybrid System

HSV-1 B capsids are composed of seven major proteins, designated VP5, VP19C, 21, 22a, VP23, VP24, and VP26. VP indicates that the capsid protein is also a component of the infectious virion. Capsid proteins 21, 22a, and VP24 are specified by a single open reading frame (UL26) that encodes 635 amino acids. An objective of the work in our laboratory is to identify and map interactions among and between capsid proteins. In the present studies we employed the yeast GAL4 two-hybrid system developed by Fields and his colleagues (Nature240, 245–246 (1989)) for this purpose. DNA corresponding to the capsid open reading frames was derived as a PCR product and fused to sequences of the GAL4 activation and DNA binding domains. Using this system each of the capsid proteins has been tested for interactions with all of the other capsid proteins. Three interactions have been identified: a relatively strong self-interaction between 22a molecules (residues 307–635 of UL26), bimolecular interactions between 22a and VP5, and another between VP19C and VP23. The interactions were detected by the expression of β-galactosidase enzyme activity, and yielded 289, 86, and 63 units of enzyme activity, respectively. For the 22a self-interaction, elimination of residues 611–635 resulted in an approximately twofold decrease in enzyme activity. The C-terminal 25 amino acids of 22a were also essential for the bimolecular interaction between 22a and VP5.