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Age-matched Control Subjects (age-matched + control_subject)
Selected AbstractsSensory nerve conduction deficit in experimental monoclonal gammopathy of undetermined significance (MGUS) neuropathyMUSCLE AND NERVE, Issue 6 2001Michael W. Lawlor BS Abstract An emerging body of evidence from in vitro studies and in vivo animal models supports a pathogenic role of antibodies in the development of peripheral neuropathy associated with monoclonal gammopathy of undetermined significance (MGUS). Although the assessment of motor and sensory nerve fiber function is of clinical importance, it is seldom applied experimentally. We describe the application of an electrophysiologic method for the evaluation of motor and sensory nerve fiber function using an experimental model of MGUS neuropathy. Supramaximal stimulation of the tibial nerve elicited an early motor response (M-wave, 1.7 ± 0.1 ms, n = 10) and a late sensory (H-reflex, 7.8 ± 0.1 ms, n = 10) response that was recorded from the hind foot of anesthetized rats. Intraneural injection of serum antibodies from a MGUS patient with sensorimotor polyneuropathy, but not from an age-matched control subject, produced a marked attenuation of the H-reflex (P < 0.01, n = 10) without affecting the M-wave. Light and electron microscopy of affected nerve showed myelinoaxonal degeneration with sparing of the smaller unmyelinated nerve fibers. The combined electrophysiologic and morphologic findings presented in this study are consistent with a selective sensory conduction deficit in MGUS neuropathy. Selective injury of afferent nerve fibers by this patient's serum antibodies may result from reactivity to neural antigens uniquely expressed by sensory neurons. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 809,816, 2001 [source] Analysis of bone mineral density in urolithiasis patientsINTERNATIONAL JOURNAL OF UROLOGY, Issue 4 2005HIDENORI TSUJI Abstract Background:, The association between hypercalciuria and bone mineral density (BMD) has been already recognized. The aim of the present study is to relate BMD to age and sex and to evaluate the calcium metabolism and hypercalciuria-defined dietary or non-dietary category in patients with urolithiasis. Methods:, The BMI of the L2,L4 lumbar vertebrae was measured in 310 renal stone patients (191 men and 119 women). Percent age matched score (%AMS), which is the percent ratio of measured BMD to the mean BMD of age-matched control subjects, was utilized for the appraisal of BMD. Low BMD groups were defined by lower than 90% of %AMS. Results:, Low BMD was observed in 27.7% of urinary stone patients, which was not a significant difference to that of control subjects (23.5%) who were measured in the health examination. In male patients with urolithiasis, the frequency of patients in whom BMD had been apt to decrease since youth was high, but there was not a proven significant difference among the three age groups (20,39 years old, 40,59 years old and 60 years old or older). In contrast, for female stone patients, the frequency of low BMD markedly increased in patients aged 40 years or older, when menopause occurs. Furthermore, in female stone patients with hypercalciuria, the frequency of reduced BMD reached more than 40%. When the cause was non-dietary hypercalciuria (classified mainly on the daily amount of urinary calcium excretion after ingestion of calculus test diet), the frequency of reduced BMD reached 65% (P < 0.01). Conclusions:, In case female stone patients with non-dietary hypercalciuria become menopausal, not only the risk of recurrent lithiasis increases, but the possibility of developing osteopenia in the future also increases. Appropriate treatments for prophylactic effects on urolithiasis or osteopenia should be considered, as judged from BMD, diet, sex, urinary calcium excretion and other factors synthetically. [source] Increased oxidative damage in nuclear and mitochondrial DNA in mild cognitive impairmentJOURNAL OF NEUROCHEMISTRY, Issue 3 2006Jianquan Wang Abstract Increasing evidence suggests that oxidative damage is associated with normal aging and several neurodegenerative diseases. Mild cognitive impairment (MCI), the phase between normal aging and early dementia, is a common problem in the elderly with many subjects going on to develop Alzheimer's disease (AD). Although increased DNA oxidation is observed in the AD brain, it is unclear when the oxidative damage begins. To determine if DNA oxidation occurs in the brain of subjects with MCI, we quantified multiple oxidized bases in nuclear and mitochondrial DNA isolated from frontal, parietal and temporal lobes and cerebellum of short post-mortem interval autopsies of eight amnestic patients with MCI and six age-matched control subjects using gas chromatography/mass spectrometry with selective ion monitoring. We found statistically significant elevations (p < 0.05) of 8-hydroxyguanine, a widely studied biomarker of DNA damage, in MCI nuclear DNA from frontal and temporal lobe and in mitochondrial DNA from the temporal lobe compared with age-matched control subjects. Levels of 8-hydroxyadenine and 4,6-diamino-5-formamidopyrimidine were significantly elevated in nuclear DNA from all three neocortical regions in MCI. Statistically significant elevations of 4,6-diamino-5-formamidopyrimidine were also observed in mitochondrial DNA of MCI temporal, frontal and parietal lobes. These results suggest that oxidative damage to nuclear and mitochondrial DNA occurs in the earliest detectable phase of AD and may play a meaningful role in the pathogenesis of this disease. [source] Change in serum COMP concentration due to ambulatory load is not related to knee OA StatusJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 11 2009Annegret Mündermann Abstract 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 [source] Altered Motor Cortex Excitability to Magnetic Stimulation in Alcohol Withdrawal SyndromeALCOHOLISM, Issue 4 2010Raffaele Nardone Background:, Alcohol addiction is a complex brain disease caused by alterations in crucial neurotransmitter systems, including gamma-aminobutyric acid (GABA) and glutamate. These disturbances could be revealed by changes in cortical excitability parameters, as assessed by transcranial magnetic stimulation (TMS). This study was aimed to further investigate the complex pathophysiology of alcohol withdrawal syndrome (AWS). Methods:, Motor cortex excitability was examined in 13 subjects with AWS in a mild predelirial state, in 12 chronic alcoholics and in 15 age-matched control subjects, using a range of TMS protocols. Central motor conduction time, resting and active motor threshold, duration of the cortical silent period, short latency intracortical inhibition (SICI), and intracortical facilitation (ICF) to paired TMS were examined. Results:, Intracortical facilitation was significantly increased in the AWS patients when compared with the chronic alcoholics and the control subjects. The other TMS parameters did not differ significantly from the controls. Administration of a single oral dose of the glutamatergic antagonist riluzole in a subgroup of 8 patients significantly reduced ICF; motor threshold and SICI were not affected by riluzole. Conclusion:, Transcranial magnetic stimulation shows a selective increase in intracortical facilitation after ethanol withdrawal. Our findings support the theory that altered glutamatergic receptor function plays an important role in the pathogenesis of human alcohol withdrawal. This study provides further physiological evidence that antiglutamatergic approaches represent an efficacious alternative for treating alcohol withdrawal symptoms. [source] Up-regulation of a growth arrest and DNA damage protein (GADD34) in the ischaemic human brain: implications for protein synthesis regulation and DNA repairNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2004F. White GADD34 is a growth arrest and DNA damage inducible gene up-regulated in response to DNA damage, cell cycle arrest and apoptosis. It is thought that GADD34 may play a crucial role in cell survival in ischaemia. GADD34 expression was assessed immunohistochemically in post-mortem human hippocampal tissue obtained from patients surviving for defined periods (0,24 h; 24 h,7 days) after a cardiac arrest and in age-matched control subjects. In control brain, cytoplasm staining in GADD34 immunopositive cells was faint but present throughout the hippocampus and cortex. There was minimal change in GADD34 expression in the group surviving 0,24 h after cardiac arrest. However GADD34 immunostaining was markedly increased in selectively vulnerable regions in the 24 h,7 day survival group. Increased GADD34 staining was present in ischaemic neurones and in some morphologically normal neurones after cardiac arrest. Extensive ischaemic damage was found to correlate with elevated GADD34 immunostaining in the CA1 layer of the hippocampus (**P < 0.0016). In addition, GADD34 was found to colocalize with proliferating cell nuclear antigen in some neurones. The up-regulation of GADD34 in response to global ischaemia in the human brain plus its influence on protein synthesis and DNA repair suggests that this protein may have the potential to influence cell survival. [source] Sexual Function and Obstructive Sleep Apnea,Hypopnea: A Randomized Clinical Trial Evaluating the Effects of Oral-Appliance and Continuous Positive Airway Pressure TherapyTHE JOURNAL OF SEXUAL MEDICINE, Issue 4ii 2007Aarnoud Hoekema DMD ABSTRACT Introduction., The obstructive sleep apnea,hypopnea syndrome (OSAHS) is associated with sexual dysfunction. Although successful treatment with continuous positive airway pressure (CPAP) has been demonstrated to improve sexual function, the effects of oral-appliance therapy are unknown. Aim., The aims of this study were to determine to what extent untreated male OSAHS patients experience sexual dysfunctions compared with control subjects, and second, to evaluate the effects of oral-appliance and CPAP therapy on sexual functioning. Methods., Sexual functioning was determined in 48 OSAHS patients with the Golombok Rust inventory of sexual satisfaction (GRISS) and a testosterone measurement. GRISS outcomes were compared with 48 age-matched male controls without any sexual problems. Patients were randomized for either oral-appliance or CPAP therapy. After 2,3 months of treatment, the GRISS and testosterone measurements were repeated. Main Outcome Measure., The outcomes on the GRISS were used as the main outcome measure. Results., Compared with controls, OSAHS patients had significantly more erectile dysfunction (mean ± standard deviation; OSAHS 8.7 ± 3.8 vs. controls 6.8 ± 2.6) and sexual dissatisfaction (mean ± standard deviation; OSAHS 9.7 ± 4.2 vs. controls 8.1 ± 2.6) as indicated by the GRISS. No significant changes in the GRISS or testosterone levels were observed in the 20 and 27 patients completing the follow-up review for oral-appliance and CPAP therapy. A correlation was demonstrated between the extent of erectile dysfunction at baseline and improvements in erectile function following treatment (r = ,0.547, P = 0.000). Conclusions., This study confirms that male OSAHS patients show more sexual dysfunctions compared with age-matched control subjects. Although significant improvements in sexual functioning in neither the oral-appliance nor CPAP-treated group could be established, our findings suggest that untreated OSAHS patients with pronounced erectile dysfunction experience some improvement following treatment. Hoekema A, Stel A-L, Stegenga B, van der Hoeven JH, Wijkstra PJ, van Driel MF, and de Bont LGM. Sexual function and obstructive sleep apnea,hypopnea: A randomized clinical trial evaluating the effects of oral-appliance and continuous positive airway pressure therapy. J Sex Med 2007;4:1153,1162. [source] Brain metabolism in rett syndrome: Age, clinical, and genotype correlations,ANNALS OF NEUROLOGY, Issue 1 2009Alena Horská PhD Objective Brain metabolism, as studied by magnetic resonance spectroscopy (MRS), has been previously shown to be abnormal in Rett syndrome (RTT). This study reports the relation of MRS findings to age, disease severity, and genotype. Methods Forty RTT girls (1,14 years old) and 12 age-matched control subjects were examined. Single-voxel proton MRS of left frontal white matter was performed. Results NAA/Cr ratios decreased and myoinositol/Cr ratios increased with age in RTT patients (both p < 0.03), whereas these ratios were stable in control. The mean glutamate and glutamine/Cr ratio was 36% greater in RTT patients than in control (p = 0.043). The mean NAA/Cr ratio was 12.6% lower in RTT patients with seizures compared with those without seizures (p = 0.017). NAA/Cr ratios decreased with increasing clinical severity score (p = 0.031). Compared with patients with T158X, R255X, and R294X mutations, and C-terminal deletions, patients with the R168X mutation tended to have the greatest severity score (0.01 , p , 0.11) and the lowest NAA/Cr ratio (0.029 , p < 0.14). Interpretation Decreasing NAA/Cr and increasing myoinositol/Cr with age are suggestive of progressive axonal damage and astrocytosis in RTT, respectively, whereas increased glutamate and glutamine/Cr ratio may be secondary to increasing glutamate/glutamine cycling at the synaptic level. The relations between NAA/Cr, presence or absence of seizures, and disease severity suggest that MRS provides a noninvasive measure of cerebral involvement in RTT. Ann Neurol 2009;65:90,97 [source] Electrocardiographic Transmural Dispersion of Repolarization in Patients with Inherited Short QT SyndromeANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2008Olli Anttonen M.D. Background: Short QT syndrome (SQTS) carries an increased risk for sudden cardiac death. However, only a short QT interval does not express the risk of ventricular arrhythmias. Thus, additional evaluation of the repolarization abnormality in SQTS patients is essential. In experimental models of SQTS, increased transmural dispersion of repolarization (TDR) and its electrocardiographic counterpart T-wave peak to T-wave end interval (TPE) appeared critical for induction of polymorphic ventricular tachycardia (PMVT). In a clinical study with acquired long QT syndrome patients, TPE/QT ratio > 0.28 indicated arrhythmia risk. We hypothesized that the TPE/QT ratio would be greater in SQTS patients than in control subjects. Methods and Results: We compared the behavior of the electrocardiographic TDR in three seriously symptomatic SQTS patients of unknown genotype presenting baseline QTc values <320 ms and in nine healthy age-matched control subjects. We determined QT and TPE intervals as well as TPE/QT ratio from 24-hour ECG recordings using a computer-assisted program. Diurnal average of TPE/QT ratio was 0.28 ± 0.03 in SQTS patients and 0.21 ± 0.02 in control subjects (P = 0.01). SQTS patients had also lesser capacity to change TPE intervals from steady-state conditions to abrupt maximal values than control subjects. Conclusion: SQTS patients have increased and autonomically uncontrolled electrocardiographic TDR. According to experimental SQTS models, the present results may in part explain increased vulnerability of SQTS patients to ventricular arrhythmias. [source] 4335: Correlation of diabetic corneal neuropathy and retinopathyACTA OPHTHALMOLOGICA, Issue 2010E NITODA Purpose Corneal confocal microscopy is a rapid, non-invasive and reiterative technique, suitable for the accurate detection and quantification of corneal subbasal nerve plexus. The aim of this study is to correlate corneal nerve fibre alterations with the abnormalities in the retina of diabetic patients and compare them with those of nondiabetic people Methods 278 diabetic corneas and 94 corneas of age-matched control subjects were included in the study. Diabetic patients were further classified with respect to the stage of retinopathy, according to indirect fundoscopy, fundus photography and fluorescein angiography. The central corneas were scanned with HRT II and we estimated nerve fibre density (NFB) nerve branch density (NBD), nerve fibre length (NFL) and nerve fibre tortuosity (NFT). Finally, we made out the glycemic and lipidemic profile of patients. Results NFD values for control, NDR, NPDR and PDR groups were 31.27 ± 0.99, 27.35 ± 0.77, 23.67 ± 0.83 and 18.77 ± 0.77 respectively and NBD values were 45.12± 2.85, 39.86 ± 3, 30.56 ± 2.71 and 24.98 ± 2.08 respectively. NFL values for control, NDR, NPDR and PDR were 16.58 ± 0.55, 14.82 ± 0.56, 12.27 ± 0.49 and 10.41± 0.45 respectively and NFT values were 5.78 ± 0.28, 6.6 ± 0.52, 6.57 ± 0.22 and 7.02 ± 0.39 respectively. NFD, NBD, NFL were significantly reduced and NFT appeared to be higher in diabetic patients, according to the stage of diabetic retinopathy. The glycemic profile was analogue to the retina status, but the lipidemic one appeared to vary. Conclusion Alterations in corneal nerve plexus are apparent in diabetic patients and more pronounced in PDR.Corneal confocal microscopy could be a promising technique for the early diagnosis and treatment of diabetic neuropathy. [source] | |||||||||||||