Change in serum COMP concentration due to ambulatory load is not related to knee OA Status

The aim of this study was to test the hypothesis that a change in serum cartilage oligomeric matrix protein (COMP) concentration is related to joint load during a 30‐min walking exercise in patients with medial compartment knee osteoarthritis (OA) and in age‐matched control subjects. Blood samples were drawn from 42 patients with medial compartment knee OA and from 41 healthy age‐matched control subjects immediately before, immediately after, and 0.5, 1.5, 3.5, and 5.5 h after a 30‐min walking exercise on a level outdoor walking track at self‐selected normal speed. Serum COMP concentrations were determined using a commercial ELISA. Basic time–distance gait variables were recorded using an activity monitor. Joint loads were measured using gait analysis. Serum COMP concentrations increased immediately after the walking exercise (+6.3% and +5.6%; p < 0.001) and decreased over 5.5 h after the exercise (?11.1% and ?14.6%; p < 0.040 and p = 0.001) in patients and control subjects, respectively. The magnitude of increase in COMP concentration did not differ between groups (p = 0.902) and did not correlate with any variables describing ambulatory loads at the joints of the lower extremity. These results, taken together with a previous study of a younger healthy population, suggest the possibility that the influence of ambulatory loads on cartilage turnover is dependent on age. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1408–1413, 2009     

Serum cartilage oligomeric matrix protein (COMP) in knee osteoarthritis: A novel diagnostic and prognostic biomarker

A case–control study was conducted to estimate the association of cartilage oligomeric matrix protein (COMP) with knee osteoarthritis (OA) and to examine the potential utility of COMP as a diagnostic and prognostic biomarker in early knee OA. The COMP levels were estimated in the blood sera of 150 subjects belonging to study group (n = 100) and control one (n = 50). Patients with confirmed clinical isolated knee OA diagnosed through American College of Rheumatology criteria were included and were without any other cause of knee pain. ELISA was used to determine the levels of COMP, interleukin‐1β (IL‐1β) and tumor necrosis factor‐α (TNF‐α). The median (range) serum COMP levels were observed to be 1117.21 ng/ml (125.03–4209.75 ng/ml) in OA patients and 338.62 ng/ml (118–589 ng/ml) in control subjects with p < 0.001. The COMP levels of study group were negatively correlated (correlation factor ?0.88) with disease duration and positively correlated with age, BMI, pain score and IL‐1β with correlation factors 0.86, 0.63, 0.76, and 0.79, respectively with p < 0.001. Gender differentiation was found in study group with 52% higher COMP level in males as compared to that of females. There was no significant correlation of COMP levels with radiological grading, erythrocyte sedimentation rate (ESR), hemoglobin (Hb), and TNF‐α. The serum COMP levels may be used as a diagnostic OA marker along with prognostic value in determining the patients at risk of rapidly progressing this debilitating joint disease. The serum COMP level remains significantly high in first 3 years of disease duration. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:999–1006, 2013

     

Dose-response relations of doxacurium and its reversal with neostigmine in young adults and healthy elderly patients.

Dose-response relationships for doxacurium and neostigmine were established in 24 young (18-40 yr) and 24 elderly (70-85 yr) patients, ASA physical status I or II, anesthetized with thiopental, fentanyl, nitrous oxide, and isoflurane. Mechanomyographic response of the adductor pollicis muscle to the train-of-four stimulation of the ulnar nerve was recorded. Doxacurium (5, 10, 15, or 20 micrograms/kg IV) was administered by random allocation. After maximal blockade, and additional dose, for a total of 30 micrograms/kg, was administered. When first twitch height recovered to 25%, incremental doses of 5 micrograms/kg were administered for maintenance of relaxation. Neostigmine (5, 10, 20, or 40 micrograms/kg) was injected at 25% first twitch recovery, and neuromuscular monitoring was continued for 10 min. The doses of doxacurium (+/- SEM) required to produce a 50%, 90%, and 95% depression of twitch tension in the young patients were, respectively, 13.3 +/- 1.6, 23.6 +/- 2.8, and 28.6 +/- 3.4 micrograms/kg, not statistically different from corresponding values in the elderly, 11.8 +/- 1.3, 21.2 +/- 2.3, and 25.9 +/- 2.9 micrograms/kg, respectively. Time to 25% recovery after 30 micrograms/kg was 80.2 +/- 12.2 min in the young versus 133.0 +/- 17.1 min in the elderly (P less than 0.05). Neostigmine-assisted recovery was not significantly different in both groups. The estimated doses of neostigmine to obtain 70% train-of-four recovery after 10 min were 53.6 +/- 7.5 micrograms/kg in the young and 41.6 +/- 5.8 micrograms/kg in the elderly (P = NS).(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of body position and axial load on spinal stiffness in healthy young adults

This study aimed at investigating the effects of different body positions and axial loads on spinal stiffness to better understand spinal stabilisation mechanisms. The posterior-to-anterior lumbar and thoracic spinal stiffness of 100 young healthy adults (mean age 23 years; 50 females) were measured in three test situations: prone, standing and standing while carrying a load equal to 50% of the subject’s body weight. Each test situation comprised three trials. Spinal stiffness in all test situations showed good reliability. Repeated measures analysis of covariance showed significantly higher spinal stiffness in standing than in the prone position [F(1/1694) = 433.630, p < 0.001]. However, spinal stiffness was significantly lower when standing while carrying a load of 50% of the body weight than when standing without additional load [F(1/1494) = 754.358, p < 0.001]. This study showed that spinal lumbar and thoracic stiffness increases when body position is changed from prone to standing. Additional axial load of 50% of the subject’s body weight results in reduced spinal stiffness during standing. These slides can be retrieved under Electronic Supplementary Material.     

Absence of relationship between tuberculin reactivity and atopy in BCG vaccinated young adults

BACKGROUND: An inverse association between tuberculin responses and atopy has been observed in Japanese children, indicating that BCG immunisation, subclinical exposure to Mycobacterium tuberculosis without clinical disease, or host characteristics may influence the T helper (Th) lymphocyte balance with decreased atopy as a result. This study was undertaken to determine whether tuberculin reactivity is inversely related to atopy in young adults vaccinated with BCG at the age of 14. METHODS: Men and women aged 20-44 years were tested using the adrenaline-Pirquet test with Norwegian produced synthetic medium tuberculin (n = 891). In addition, their serum total and specific IgE antibodies against mite, cat, timothy grass, mould and birch were measured. RESULTS: Of the 574 subjects with complete examinations, 64% had a positive adrenaline-Pirquet tuberculin test (> or =4 mm) and 27% exhibited IgE antibodies (> or =0.35 kU/l) to one or more of the five specific allergens. The geometric mean of total serum IgE in the population was 30.2 kU/l. Tuberculin reactivity and log IgE were not correlated (r = 0.043, p = 0.30). The mean tuberculin reactivity was 4.6 mm, 4.9 mm, and 5.0 mm in the lower, middle and upper tertile of IgE distribution (<14 kU/l, 14-61 kU/l, >61 kU/l). The prevalence of atopy, as assessed by either the presence of any of the five specific IgE antibodies or by each specific IgE antibody separately, did not differ between subjects with a positive and those with a negative tuberculin test. These results persisted after adjustment for age, sex, and smoking status in multivariate logistic regression analyses. CONCLUSIONS: In this young adult population, BCG vaccinated at the age of 14, no significant relationship between a positive tuberculin reaction and atopy was observed. If a true relationship had been found, our study suggests that it may be limited to populations immunised in early childhood when a substantial modulation of the immune system can occur.     

The relationship between PTC taster status and taste thresholds in young adults.

OBJECTIVE: The aim of this study was to compare taste detection and recognition thresholds of young males and females, and young phenylthiocarbamide (PTC) "tasters" and "nontasters" for stimuli representing sweet, sour, bitter, salty, and umami classes of taste sensations. STUDY DESIGN: Thirty-eight men and 37 women (mean [SD] age = 24.5 [2.5] years) were classified as PTC tasters and nontasters according to their PTC recognition thresholds. Detection and recognition thresholds for the non-PTC stimuli were determined using a 2-alternative, forced choice procedure. RESULTS: The detection thresholds for quinine-HCl and sucrose and the recognition threshold for quinine-HCl were significantly higher in the PTC nontasters than in the tasters. The PTC threshold showed significant correlations with detection or recognition thresholds for sucrose, sodium chloride, quinine-HCl, and monosodium glutamate. The sucrose recognition threshold was lower in women than in men. CONCLUSION: In this study, gender and PTC taster status were found to be associated with thresholds for sucrose and quinine-HCl.     

肾移植围手术期醛固酮的变化与肾功能的关系研究

目的  分析肾移植患者围手术期醛固酮与肾功能变化的关系, 从而初步探讨醛固酮在慢性移植肾肾病中的作用。方法  选取2010年1月1日到2013年12月31日, 在沈阳军区总医院泌尿外科行同种异体肾移植患者共100例作为实验组, 根据肾移植术后30 d时Scr水平将实验组再分为A组(Scr≥133 μmol/L, 13例)和B组(Scr < 133 μmol/L, 87例)。另选取年龄在25~35岁之间身体健康的志愿者10名, 作为对照组。实验组在肾移植的当日(0 d)、移植术后1、7、15、30 d清晨抽血, 对照组在相应时段抽血, 测定血清醛固酮和Scr水平。结果  肾移植当日, 实验组和对照组的Scr水平分别为(598±37)μmol/L和(75±5)μmol/L, 醛固酮水平分别为(0.26±0.06) ng/dl和(0.13±0.03) ng/dl, 两组比较差异均有统计学意义(P < 0.05)。与0 d同组比较, 术后30 d A组受者Scr水平降低, 差异有统计学意义(P < 0.05), 醛固酮水平变化不大, 差异无统计学意义(P > 0.05);术后30 d B组受者Scr和醛固酮水平均明显降低, 差异均有统计学意义(均为P < 0.05)。相关分析结果显示, 实验组的血清醛固酮与Scr的变化均呈正相关(r=0.85, P < 0.05)。结论  肾移植术后Scr及醛固酮的变化趋势呈正相关, 初步认为醛固酮在介导移植肾损伤过程中发挥着一定的作用。     

Vitamin D status and its relationship with bone mineral density in healthy Asian Indians

Synthesis of vitamin D takes place in the skin under the effect of sunlight. The Indian subcontinent is situated between 8.4° N and 37.6° N latitudes and has adequate sunshine throughout the year. Thus, it has been presumed that Indians are vitamin D sufficient. We measured serum 25-hydroxy vitamin D [25(OH)D] (n=92) and 1,25-dihydroxy vitamin D [1, 25(OH)₂D] (n=65) levels in healthy hospital staff, using ¹²⁵I radioimmunoassay. Serum intact parathyroid hormone (PTH) concentration was estimated by immunoradiometric assay. Bone mineral density was estimated using a dual energy X-ray absorptiometer (Hologic^R QDR 4500A). Using a serum 25(OH)D level of 15 ng/ml as a cutoff, 66.3% (61/92) of the subjects were found to be vitamin D deficient. Of these, 20.6% (19/92) subjects had severe vitamin D deficiency (<5 ng/ml), 27.2% (25/92) had moderate vitamin D deficiency (5–9.9 ng/ml), while 18.5% (17/92) had mild vitamin D deficiency (10–14.9 ng/ml). When a serum 25(OH)D level of 20 ng/ml was used as a cutoff, 78.3% subjects were diagnosed to be vitamin D deficient/insufficient. The serum 1,25(OH)₂D level was within the normal range (40.6±20.1 pg/ml; mean ± SD). Mean (±SD) serum intact PTH, estimated in a limited number of subjects (n=15), was 72.3 (±21.0) pg/ml (range 36–100 pg/ml). There was a significant correlation between daily sun exposure and 25(OH)D levels (r=0.731, P<0.001). The serum 25(OH)D level correlated with BMD at the femoral neck and Ward's triangle (r=0.50, P=0.020 and r=0.46, P=0.037, respectively). Our findings show that vitamin D deficiency is common in urban north Indian hospital staff. The possible reasons include inadequate sunlight exposure and skin pigmentation in Indians. The serum 1,25(OH)₂D level is not a good indicator of vitamin D deficiency. A low serum 25(OH)D level is possibly one of the reasons for lower bone mineral density among Indians.     

Ten-year longitudinal relationship between physical activity and lumbar bone mass in (young) adults.

Little is known about the influence of long-term daily physical activity (PA) on lumbar bone mass after peak bone mass has been reached, that is, during [young] adulthood. The purpose of this study was to investigate the longitudinal relationship between PA and lumbar bone mineral density (LBMD) in healthy subjects over a 10-year period. The data reported here relate to 225 male and 241 female participants in the Amsterdam Growth and Health Longitudinal Study, who were measured at the mean ages of 27, 32, and/or 36. LBMD, habitual daily PA, total body weight, and calcium intake were assessed at each measurement point. The effects of two aspects of PA were analyzed: the mechanical (MECHPA; sum of all ground reaction forces) and metabolic (METPA; weighted metabolic score of intensity, frequency, and duration) components, each within a separate model. Multilevel analysis was used to investigate the relationship between PA and LBMD over the 10-year period. Gender, total body weight, and calcium intake were included in the analysis as covariates. The results indicated that MECHPA was a significant positive linear predictor of LBMD for males (r = 0.09; p < 0.001) but not for females. For the METPA, no linear longitudinal relationship with LBMD was found. The results suggest that there is a metabolic threshold at which extra PA becomes "deleterious" and METPA in its totality becomes ineffective for LBMD. It is concluded that during the (young) adult period, between 27 and 36 years of age, PA causing mechanical loading on the skeleton has a small positive influence on LBMD in males.     

Combining walking and relaxation for stress reduction—A randomized cross‐over trial in healthy adults

Both physical activity and relaxation have stress‐relieving potential. This study investigates their combined impact on the relaxation response while considering participants' initial stress level. In a randomized cross‐over trial, 81 healthy adults completed 4 types of short‐term interventions for stress reduction, each lasting for 1 hr: (1) physical activity (walking) combined with resting, (2) walking combined with balneotherapy, (3) combined resting and balneotherapy, and (4) resting only. Saliva cortisol, blood pressure, state of mood, and relaxation were measured preintervention and postintervention. Stress levels were determined by validated questionnaires. All interventions were associated with relaxation responses in the variables saliva cortisol, blood pressure, state of mood, and subjective relaxation. No significant differences were found regarding the reduction of salivary cortisol (F = 1.30; p = .281). The systolic blood pressure was reduced best when walking was combined with balneotherapy or resting (F = 7.34; p < .001). Participants with high stress levels (n = 25) felt more alert after interventions including balneotherapy, whereas they reported an increase of tiredness when walking was combined with resting (F = 3.20; p = .044). Results suggest that combining physical activity and relaxation (resting or balneotherapy) is an advantageous short‐term strategy for stress reduction as systolic blood pressure is reduced best while similar levels of relaxation can be obtained.     

Brain networks associated with cognitive reserve in healthy young and old adults

In order to understand the brain networks that mediate cognitive reserve, we explored the relationship between subjects' network expression during the performance of a memory test and an index of cognitive reserve. Using H2(15)O positron emission tomography, we imaged 17 healthy older subjects and 20 young adults while they performed a serial recognition memory task for nonsense shapes under two conditions: low demand, with a unique shape presented in each study trial; and titrated demand, with a study list size adjusted so that each subject recognized shapes at 75% accuracy. A factor score that summarized years of education, and scores on the NART and the WAIS-R Vocabulary subtest was used as an index of cognitive reserve. The scaled subprofile model was used to identify a set of functionally connected regions (or topography) that changed in expression across the two task conditions and was differentially expressed by the young and elderly subjects. The regions most active in this topography consisted of right hippocampus, posterior insula, thalamus, and right and left operculum; we found concomitant deactivation in right lingual gyrus, inferior parietal lobe and association cortex, left posterior cingulate, and right and left calcarine cortex. Young subjects with higher cognitive reserve showed increased expression of the topography across the two task conditions. Because this topography, which is responsive to increased task demands, was differentially expressed as a function of reserve level, it may represent a neural manifestation of innate or acquired reserve. In contrast, older subjects with higher cognitive reserve showed decreased expression of the topography across tasks. This suggests some functional reorganization of the network used by the young subjects. Thus, for the old subjects this topography may represent an altered, compensatory network that is used to maintain function in the face of age-related physiological changes.     

颈椎间盘压缩力学性能改变与终板蛋白多糖变化关系的实验研究

目的:探讨颈椎间盘退变时基质各成分的变化及其对椎间盘力学性能的影响。方法:将24只家兔随机分为对照组和模型组(n=12),模型组保持45°低屈曲位5h/次/d,最长持续3个月。分别于造模后1、2、3个月时各处死4只动物,取C5/6椎间盘测定终板糖胺多糖(glycosaminoglycan,GAG)总量、硫酸软骨素(chongdroitinsulphate,CS)与硫酸角质素(keratansulphate,KS)比值和透明质酸(hyaluronicacid,HA)含量;同时作力学测定。结果:模型组终板抗压强度、断裂时的最大形变、终板基质GAG总含量、CS/KS比值、HA含量都低于对照组(P<0.05),并随造模时间的延长两组差异越显著。结论:长时间的应力不均可造成椎间盘终板材料力学特性改变;终板蛋白多糖含量和成分改变可能是颈椎间盘生物力学性能减退的主要原因之一。     

Longitudinal measurement of regional and whole body bone mass in young healthy adults

The so-called peak bone mass (PBM) represents the highest amount of bony tissue achieved during life at a given site of the skeleton. It has been suggested that PBM might be achieved as late as the fourth decade, but recent data have indicated that PBM is already achieved by the end of sexual maturation, namely at the end of the second decade. The solving of this apparent controversy is of interest for a better understanding of bone homeostasis and for defining the cohort of normal subjects to be evaluated in order to establish a PBM reference range — necessary for the diagnosis of osteoporosis and evaluation of the fracture risk. To study bone mass evolution in young healthy adults and to determine whether such a cohort can be used to establish PBM reference values, we measured bone mineral density (BMD) in sixty 20- to 35-year-old young healthy adults by dual-energy X-ray absorptiometry at the levels of the lumbar spine (in both anteroposterior and lateral views), femoral neck, trochanter region, total hip and of Ward's triangle, as well as whole-body BMD and bone mineral content (BMC) in cross-sectional and longitudinal studies. In the cross-sectional analysis, none of the bone mass variables was dependent on age using linear regression analysis. The longitudinal study indicated that the mean changes in lumbar spine, proximal femur and whole body BMD or BMC determined after a 1-year interval were not statistically different from zero in either females or males aged 20–35 years. In conclusion, the present results confirm that at the levels of lumbar spine and proximal femur, two sites particularly at risk of osteoporotic fractures, PBM can be achieved before the third and fourth decades in both male and female normal subjects.     

膝关节骨关节炎内侧间室软骨病损的MRI表现与关节镜术后疗效的相关性研究

目的探讨膝关节骨关节炎（OA）内侧间室软骨病损的MRI表现和关节镜手术后疗效的相关性及膝关节OA的关节镜手术适应证。方法对92例关节镜手术病例,其中男54例,女38例;年龄43～69岁,平均58.5岁。对患者膝关节股骨内髁和胫骨内侧平台软骨的MRI表现按ICRSMR分级标准进行分级,对所有患者均进行了术后12～30个月的随访,随访时进行Lysholm评分。结果 92例92个膝关节,核磁共振显示关节软骨损伤Ⅳ级10例;Ⅲ级16例;Ⅱ级20例;Ⅰ级25例;0级21例,分级的均数为（1.66±1.303）;术后Lysholm评分最高100分;最低64分,评分的均数（95.42±7.398）。术后Lysholm评分与ICRSMR分级相关系数r=-0.672,P〈0.05,统计学处理呈负相关。结论认为术前膝关节内侧间室软骨的MRI（1.5T）分级对膝关节OA关节镜手术指征的判断有重要的参考价值。     

Differences in new-onset IgA nephropathy between young adults and the elderly

Background: The goal of this study was to define the clinical and histological differences in new-onset IgA nephropathy between young adults and the elderly. Methods: We retrospectively examined renal biopsy findings, clinical features at presentation and outcomes in 82 young adults (mean age 30.3 ± 10.2 years) and 17 elderly patients (mean age 71.9 ± 4.5 years) with IgA nephropathy whose renal biopsies were taken within 1 year from the onset of renal manifestations. Results: The elderly group more frequently had hypertension (p < 0.001), acute renal failure (p < 0.001), and nephrotic range proteinuria (p = 0.001) at presentation than the young adults group. On histology, a higher percentage of globally sclerotic glomeruli (p < 0.001) was present in the elderly group. In patients presenting with acute renal failure, the elderly group more frequently had an intercurrent disease (p = 0.02), mostly infection, and a higher mortality rate (p = 0.033). On histology, the young adults group had a higher percentage of glomeruli affected by crescents (p = 0.027); in contrast, the elderly group more commonly had acute tubular injury (p = 0.02). Conclusions: The elderly patients affected by IgA nephropathy had more severe renal manifestations at presentation (acute renal failure in 52.9% and nephrotic syndrome in 41.2% of patients). In cases of acute renal failure, the elderly patients had more predominant tubular rather than glomerular injury. Moreover, the considerable mortality rate (44.4%) might be associated with the intercurrent disease, mostly infection, which was more commonly present in the elderly patients.     

Relationships between IQ and regional cortical gray matter thickness in healthy adults

Prior studies show positive correlations between full-scale intelligence quotient (FSIQ) and cerebral gray matter measures. Few imaging studies have addressed whether general intelligence is related to regional variations in brain tissue and the associated influences of sex. Cortical thickness may more closely reflect cytoarchitectural characteristics than gray matter density or volume estimates. To identify possible localized relationships, we examined FSIQ associations with cortical thickness at high spatial resolution across the cortex in healthy young adult (age 17-44 years) men (n = 30) and women (n = 35). Positive relationships were found between FSIQ and intracranial gray and white matter but not cerebrospinal fluid volumes. Significant associations with cortical thickness were evident bilaterally in prefrontal (Brodmann's areas [BAs] 10/11, 47) and posterior temporal cortices (BA 36/37) and proximal regions. Sex influenced regional relationships; women showed correlations in prefrontal and temporal association cortices, whereas men exhibited correlations primarily in temporal-occipital association cortices. In healthy adults, greater intelligence is associated with larger intracranial gray matter and to a lesser extent with white matter. Variations in prefrontal and posterior temporal cortical thickness are particularly linked with intellectual ability. Sex moderates regional relationships that may index dimorphisms in cognitive abilities, overall processing strategies, or differences in structural organization.