Does the video head impulse test replace caloric testing in the assessment of patients with chronic dizziness? A systematic review and meta-analysis

IntroductionCaloric testing is the most frequently used test to assess peripheral vestibular function since the beginning of the 20th century. However, the video head impulse test, vHIT, has gained prominence in the field of neurotology, as it is a faster examination, easier to perform and less uncomfortable for the patient.ObjectiveTo compare, through systematic review and meta-analysis, the proportion of altered cases between vHIT tests and caloric testing in patients with chronic dizziness, in addition to assessing the sensitivity and specificity of vHIT, with caloric testing as the gold standard.MethodsThe literature search was carried out in the PubMed, Scopus, BVS-Bireme, Web of Science, Embase, Cochrane and ProQuest indexed databases, with no restrictions regarding the publication period. All articles that contained the results of the two tests were included in the evaluation of patients with dizziness. Two researchers independently conducted data selection and extraction from the studies, strictly following the inclusion and exclusion criteria defined in the research protocol. In case of disagreement during the selection, a discussion was carried out with a third evaluator.ResultsEleven of the 1293 initial articles met the eligibility criteria and were analyzed. 2670 patients were evaluated, of which 1112 (41.6%) were males and 1558 (58.4%) females, with a mean age of 51.6 years. The proportion of altered results in the vHIT was 21% (95%CI 9% –33%), and 55% in the caloric testing (95%CI 43% –67%).ConclusionThe vHIT does not substitute for caloric testing. The tests are complementary in assessing the patient with dizziness, as they describe the tonotopy of the ampullary crest at different frequency ranges of stimulation. In chronic cases, the vHIT has a low sensitivity and high diagnostic specificity in comparison to caloric testing.     

高效液相色谱串联质谱法测定氯沙坦钾中的遗传毒性杂质N-亚硝基-N-甲基-4-氨基丁酸

目的建立了一种高效液相色谱-三重四极杆串联质谱法,对氯沙坦钾原料药中遗传毒性杂质N-亚硝基-N-甲基-4-氨基丁酸(NMBA)进行测定。方法色谱柱为岛津Shim-pack XR-ODSⅡ色谱柱(2.0 mm×150 mm,2.2μm),流动相为0.1%甲酸水溶液(A)和甲醇(B),进行梯度洗脱,流速0.3 mL·min^-1,柱温为40℃,采用ESI离子化-三重四极杆质谱多反应监测(MRM)正离子模式检测,碰撞电压分别为-11,-13和-13 V,碰撞气氩气270 kPa,NMBA的离子对分别为m/z 147.15→117.10,147.15→87.10和147.15→44.10。结果该方法中NMBA在1~100 ng·mL^-1内线性关系良好,日内和日间的保留时间和峰面积的重复性良好(RSD均小于1.10%,n=6和n=18),低、中、高3个浓度的平均回收率在94.40%~98.04%之间。结论本方法简单方便,可快速有效的对氯沙坦钾原料药中NMBA进行限度检查并实现定量分析。     

The role of cardiopulmonary exercise testing in evaluating children with exercise induced dyspnoea

Exercise induced dyspnoea (EID) is a common manifestation in children and adolescents. Although EID is commonly attributed to exercise induced bronchoconstriction, several conditions other than asthma can cause EID in otherwise healthy children and adolescents. Cardiopulmonary exercise testing (CPET) offers a non-invasive comprehensive assessment of the cardiovascular, ventilatory and metabolic responses to exercise and is a powerful diagnostic and prognostic tool. CPET is a reproducible, non-invasive form of testing that allows for comparison against age- and gender-specific norms. CPET can assess the child’s exercise capacity, determine the limiting factors associated with this, and be used to prescribe individualised interventions. EID can occur due to asthma, exercise induced laryngeal obstruction, breathing pattern disorders, chest wall restriction and cardiovascular pathology among other causes. Differentiating between these varied causes is important if effective therapy is to be initiated and quality of life improved in subjects with EID.     

Prospective comparative study of intraoperative “Towel clip test” and “Vertical patella test” assessing lateral retinaculum tightness in patients undergoing TKA

BackgroundProper patellar tracking is one of the most important aspect of TKA to ensure good functional outcome. A patellar tracking problem noted intraoperatively serves as a warning sign and should prompt the surgeon to reassess position of each component. Various tests are there to assess lateral retinaculum tightness viz. "No thumb test", "Towel clip test". A new test "Vertical patella test" is described to assess lateral retinaculum tightness. A study was conducted to assess the effectiveness, correlation and validity of two techniques.Materials & MethodsPatients >50 years of age and with diagnosis of Osteoarthritis knee having less than 30 varus and flexion deformity going in for primary TKA were selected with a sample size of 100 knees in a tertiary care centre. Revision cases or patients with flexion contracture more than 30, complex knee surgery; with pre existing patellar tilt were excluded from study.ResultsResults of both tests were found to correlate in 75% of case with sensitivity of 96.65% and specificity of 75.00%. Kappa came out to be 0.634 which shows good agreement of vertical patella test and towel clip test. Result was computed using excel and SPSS and was found to be significant with p value< 0.05. Lateral retinaculum release was done in 8 knees.ConclusionsVertical patella test correlates with towel clip test, is easy to perform and saves time. The limitation of our study was small sample size.     

Addressing risk management difficulties in children with food allergies

Risk is a concept inherent in every medical procedure. It can be defined as the probability of an adverse event in a defined population over a specified period of time. In the frame of food allergy management, it might be related to a diagnostic procedure, a treatment, or the consumption of foods. The risk of an adverse event can also be augmented by individual factors. This rostrum article discusses various aspects faced by children with food allergies in the light of risk, and their practical implications. Identifying personal risks for severe reaction, such as unstable asthma, and correcting them whenever possible also contribute to a reduction of the risk inherent to food allergy. Among the facets discussed, oral food challenges (OFC) are the most common diagnostic procedures implying an inherent risk. The risk of OFCs can be minimized by correct indication and timing of the test, a safe setting, as well as by ensuring that the patient is otherwise well without potential stressor potentially increasing the risk of a more severe reaction. Oral immunotherapy (OIT) has been studied as a potential treatment for increasing the threshold dose for reaction, and thus reducing the risk of accidental reaction. Nevertheless, the procedure is not devoid of risk as the patients may and do often react during the course of the procedure. Ingestion of trace amounts in processed foods, mainly in community settings such as restaurants, schools, or day care, represents a potential risk of reactions, although for a minority of patients. Precautionary allergen labeling (PAL) is a widespread strategy to reduce the potential risk of reactions due to traces. However, PAL is currently inefficient due to inconsistent labeling, also not indicating a clear maximum amount possibly present in the manufactured food. Finally, cost-effectiveness needs to be considered in risk management, as many risk reduction procedures are clearly not cost-effective.     

Developing a Brief Neuropsychological Battery for Early Diagnosis of Cognitive Impairment

ObjectivesEarly diagnosis of cognitive impairment is increasingly emphasized in the literature to facilitate timely preventive interventions. Although bedside cognitive tests such as the Montreal Cognitive Assessment (MoCA) are widely used for such early diagnostic purposes, they may not have comparable performance to a full neuropsychological battery (FNB) in diagnosing early cognitive impairment. This study investigated whether a small subset of neuropsychological tests can be added on to MoCA to match its performance to that of the FNB in discriminating mild cognitive impairment and dementia (MCI/dementia) from normal cognition.DesignCross-sectional diagnostic study.SettingAlzheimer's Disease Centers across the United States.ParticipantsOlder participants (≥50 years) who completed MoCA and the FNB (N = 9187).MeasuresThe study sample was split into two: the derivation sample (n = 1837) was used to develop a brief neuropsychological battery that best discriminated MCI/dementia (using the best-subset approach with 10-fold cross-validation); while the validation sample (n = 7350) verified its actual performance in discriminating MCI/dementia.ResultsA 3-item neuropsychological battery was identified, comprising MoCA, Benson Complex Figure Recall, and Craft Story 21 Delayed Recall. It had excellent performance in discriminating MCI/dementia from normal cognition (area under the receiver operating characteristic curve [AUROC] 90.0%, 95% confidence interval [CI] 89.2%-90.7%), which was comparable to that of the FNB (AUROC 88.4%, 95% CI 87.6%-89.2%). By contrast, MoCA alone had significantly worse AUROC (86.9%, 95% CI 86.0%-87.7%) than that of the FNB.Conclusions/ImplicationsUsing rigorous methods, this study developed a brief neuropsychological battery that maintained the brevity of a bedside cognitive test, while rivaling the diagnostic performance of an FNB in early cognitive impairment. This brief battery offers a viable alternative when the FNB is needed but cannot be feasibly administered in nonspecialty clinics. It can have a wider health systems effect of improving patients’ access to accurate diagnosis in early cognitive impairment and facilitating timely interventions to delay the progression of cognitive impairment.     

Costimulation and Autoimmune Diabetes in BB Rats

Costimulatory signals regulate T-cell activation. To investigate the role of costimulation in autoimmunity and transplantation, we studied the BB rat model of type 1 diabetes. Diabetes-prone BB (BBDP) rats spontaneously develop disease when 55–120 days of age. We observed that two anti-CD28 monoclonal antibodies (mAb) with different functional activities completely prevented diabetes in BBDP rats. Anti-CD154 mAb delayed diabetes, whereas treatment with CTLA4-Ig or anti-CD80 mAb accelerated disease. Anti-CD86 or anti-CD134L mAbs had no effect. Diabetes resistant BB (BBDR) rats are disease-free, but >95% of them develop diabetes after treatment with polyinosinic-polycytidylic acid and an mAb that depletes Treg cells. In the induced BBDR model, anti-CD154 mAb delayed onset of diabetes, whereas CTLA4-Ig, anti-CD134L or either of the anti-CD28 mAbs had little or no effect. In contrast, blockade of the CD134-CD134L pathway was highly effective for preventing autoimmune recurrence against syngeneic islet grafts in diabetic BBDR hosts. Blockade of the CD40-CD154 pathway was also effective, but less so. These data suggest that the effectiveness of costimulation blockade in the treatment of type 1 diabetes is dependent on both the costimulatory pathway targeted and the mechanism of induction, stage, intensity and duration of the pathogenic process.     

不同浓度氯氮平对小鼠空腹血糖和骨骼肌葡萄糖转运蛋白4基因表达的影响

目的探讨氯氮平对雄性C57BL/6小鼠空腹血糖和骨骼肌葡萄糖转运蛋白4(GLUT4)基因表达的影响。方法将63只雄性C57BL/6小鼠随机分为3组,每组21只,分别灌胃给予蒸馏水、氯氮平4mg/kg及氯氮平20mg/kg,于给药后3h、1周、4周以试纸法测定各组空腹血糖,用逆转录-聚合酶链反应测定GLUT4mRNA表达。结果(1)灌药后3h、1周氯氮平4mg/kg组和氯氮平20mg/kg组空腹血糖和GLUT4mRNA的表达与空白对照组相比,差异无统计学意义(P>0.05);(2)灌药后4周氯氮平4mg/kg组和20mg/kg组的空腹血糖值[(5.6±0.5)mmol/L和(5.8±0.5)mmol/L]高于空白对照组[(4.6±0.6)mmol/L],而GLUT4mRNA的表达(0.50±0.14和0.48±0.12)却低于空白对照组(0.85±0.27),差异均有统计学意义(P<0.01)。结论氯氮平可以慢性升高空腹血糖,降低GLUT4mRNA的表达,可能是抗精神病药长期应用后血糖升高的发生机制之一。     

Kinetic modeling of PET-FDG in the brain without blood sampling

The aim in this work is to report a new method to calculate parametric images from a single scan acquisition with positron emission tomography (PET) and fluorodeoxyglucose (FDG) in the human brain without blood sampling. It is usually practical for research or clinical purposes to inject the patient in an isolated room and to start the PET acquisition only for some 10–20 min, about 30 min after FDG injection. In order to calculate the cerebral metabolic rates for glucose (CMRG), usually several blood samples are required. The proposed method considers the relation between the uptake of the tracer in the cerebellum as a reference tissue and the population based input curve. Similar results were obtained for CMRG values with the present method in comparison to the usual autoradiographic and the non-linear least squares fitting of regions of interest.     

用患者样本进行方法学对比及在两种葡萄糖测定法中的应用

目的 用患者样本分析葡萄糖氧化酶-氧电极法(简称电极法)和己糖激酶(HK)法测定血清葡萄糖(GLU)时的偏倚。方法 依据美国临床实验室标准化委员舍(NCCLS)EP9—A文件，每天取患者样本8份，分别用两种方法测定血清葡萄糖含量，共测定5d，记录检验结果，去除离群点，计算线性方程和相关系数，并进行偏倚估计。结果 在进行患者葡萄糖测定时，电极法(Y)和HK法(X)测定结果的回归方程为：Y＝0．9857X 0．08967，r^2=0．9992；电极法和HK法测定结果的预期相对偏倚在GLU＝15mmo1／L时为0．80％，GLU＝9mmo1／L时为0．44％，GLU＝6mmo1／L时为0．00％，GLU＝3mmo1／L时为1．67％。结论 电极法和HK法测定血清葡萄糖时，测定结果在低浓度时偏倚较大，在中、高浓度时偏倚较小，两法间有良好的相关性。