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[Functional disorders and functional diseases in the region of the upper cervical spine particularly regarding the cervical joints. Current status and clinical relevance].

Functional disorders of the upper cervical spine may be responsible for or the primary cause of persistent complaints following an injury or illness. Functional disorders involving the cervical joints, especially C0/C1 and C1/2 but also the C2/3 junction are of particular clinical relevance. Range of motion assessment is extremely important for the diagnosis of joint disorders. Hypomobility or "blockade" can be diagnosed using special examination techniques that, in many cases, can be extended for direct manual therapy. Periarticular structures involved in these dysfunctional processes, especially muscles and fasciae, must also be examined and treated. Clinical manifestations may include locally restricted muscle extensibility (e.g., trigger points, tension or muscle shortening) with zones of radiating pain as well as referred problems distal to the primary lesion. Functional disorders in the region of the upper cervical spine may be accompanied by various types of reflexive compensatory problems. Although they must be diagnosed separately, these disorders frequently respond to the manual therapy techniques used to treat the underlying functional problem. Even if the exact correlations to functional medicine cannot be scientifically demonstrated in every case, functional assessment and treatment techniques are, in our view, a useful addition to the armamentarium for orthopedic diagnosis and treatment.

Adult↗

Effect of isokinetic training on strength, functionality and proprioception in athletes with functional ankle instability.

The purpose of this study was to investigate the effects of isokinetic exercise on strength, joint position sense and functionality in recreational athletes with functional ankle instability (FAI). Strength, proprioception and balance of 24 recreational athletes with unilateral FAI were evaluated by using isokinetic muscle strength measurement, ankle joint position sense and one leg standing test. The functional ability was evaluated using five different tests. These were; single limb hopping course (SLHC), one legged and triple legged hop for distance (OLHD-TLHD), and six and cross six meter hop for time (SMHT-CSMHT). Isokinetic peak torque of the ankle invertor and evertor muscles were assessed eccentrically and concentrically at test speeds of 120 degrees /s. Isokinetic exercise protocol was carried out at an angular velocity of 120 degrees /s. The exercise session was repeated three times a week and lasted after 6 weeks. At baseline, concentric invertor strength was found to be significantly lower in the functionally unstable ankles compared to the opposite healthy ankles (p < 0.001). This difference was not present after executing the 6 weeks exercise sessions (p > 0.05). Ankle joint position sense in the injured ankles declined significantly from 2.35 +/- 1.16 to 1.33 +/- 0.62 degrees for 10 degrees of inversion angle (p < 0.001) and from 3.10 +/- 2.16 to 2.19 +/- 0.98 degrees for 20 degrees of inversion angle (p < 0.05) following the isokinetic exercise. One leg standing test score decreased significantly from 15.17 +/- 8.50 to 11.79 +/- 7.81 in the injured ankles (p < 0.001). Following the isokinetic exercise protocol, all of the worsened functional test scores in the injured ankles as compared to the opposite healthy ankles displayed a significant improvement (p < 0.01 for OLHD and CSMHT, p < 0.001 for SLHC, TLHD, and SMHT). These results substantiate the deficits of strength, proprioception, balance and functionality in recreational athletes with FAI. The isokinetic exercise program used in this study had a positive effect on these parameters.

Adult↗

On the Issue of Functional Form Choice in Hedonic Price Functions: Further Evidence

/ Historically, researchers applying the hedonic technique devoted little effort to testing alternative functional forms. This study used Box-Cox transformations on a hedonic model examining property value effects of a closed landfill to help select among alternative functional forms. Although this particular application found that a log-log functional form was appropriate, it appears that functional form may vary by problem and case study area selected. Benefit estimates generated using the hedonic technique may be substantial over- or underestimates if the incorrect functional form is chosen. Proximity to the landfill had no significant effect on property values.KEY WORDS: Hedonics; Functional form; Box-Cox; Landfills

Journal Article↗

Quantitative determination of human protein C. Evaluation of a "fast" functional assay in comparison to a "traditional" functional and an immunological assay.

A fast functional assay for protein C was evaluated and compared with a traditional functional and an enzyme linked immunosorbent assay in parallel for the same plasma samples derived from 43 healthy subjects, 12 patients with severe hepatic dysfunction, and 23 patients under stable oral anticoagulation. By all three test systems significantly lower levels of protein C were obtained in both groups of patients compared with normal subjects (p less than 0.0001). No significant between - assay differences were found in normal subjects and in patients with hepatic dysfunction; by correlation analysis coefficients higher than 0.8 were calculated between the measurements of the three tests. In patients under stable oral anticoagulation, however, the immunologic test yielded higher values than the traditional (p less than 0.05) and, more pronounced, the fast functional assay (p less than 0.0001); no or only borderline significant correlations between the results were found. In these patients protein C levels measured with the traditional functional assay were in the same range as the activity levels of factors II, VII, IX, and X, whereas the fast functional test yielded significantly lower levels. The presented results indicate that very similar protein C levels were obtained with both functional and the immunologic assay except in patients under oral anticoagulation.

Adult↗

From glycomics to functional glycomics of sugar chains: Identification of target proteins with functional changes using gene targeting mice and knock down cells of FUT8 as examples.

Comprehensive analyses of proteins from cells and tissues are the most effective means of elucidating the expression patterns of individual disease-related proteins. On the other hand, the simultaneous separation and characterization of proteins by 1-DE or 2-DE followed by MS analysis are one of the fundamental approaches to proteomic analysis. However, these analyses do not permit the complete structural identification of glycans in glycoproteins or their structural characterization. Over half of all known proteins are glycosylated and glycan analyses of glycoproteins are requisite for fundamental proteomics studies. The analysis of glycan structural alterations in glycoproteins is becoming increasingly important in terms of biomarkers, quality control of glycoprotein drugs, and the development of new drugs. However, usual approach such as proteoglycomics, glycoproteomics and glycomics which characterizes and/or identifies sugar chains, provides some structural information, but it does not provide any information of functionality of sugar chains. Therefore, in order to elucidate the function of glycans, functional glycomics which identifies the target glycoproteins and characterizes functional roles of sugar chains represents a promising approach. In this review, we show examples of functional glycomics technique using alpha 1,6 fucosyltransferase gene (Fut8) in order to identify the target glycoprotein(s). This approach is based on glycan profiling by CE/MS and LC/MS followed by proteomic approaches, including 2-DE/1-DE and lectin blot techniques and identification of functional changes of sugar chains.

Animals↗

Nicotine effects on brain function and functional connectivity in schizophrenia.

BACKGROUND: Nicotine in tobacco smoke can improve functioning in multiple cognitive domains. High rates of smoking among schizophrenic patients may reflect an effort to remediate cognitive dysfunction. Our primary aim was to determine whether nicotine improves cognitive function by facilitating activation of brain regions mediating task performance or by facilitating functional connectivity. METHODS: Thirteen smokers with schizophrenia and 13 smokers with no mental illness were withdrawn from tobacco and underwent functional magnetic resonance imaging (fMRI) scanning twice, once after placement of a placebo patch and once after placement of a nicotine patch. During scanning, subjects performed an n-back task with two levels of working memory load and of selective attention load. RESULTS: During the most difficult (dichotic 2-back) task condition, nicotine improved performance of schizophrenic subjects and worsened performance of control subjects. Nicotine also enhanced activation of a network of regions, including anterior cingulate cortex and bilateral thalamus, and modulated thalamocortical functional connectivity to a greater degree in schizophrenic than in control subjects during dichotic 2-back task performance. CONCLUSIONS: In tasks that tax working memory and selective attention, nicotine may improve performance in schizophrenia patients by enhancing activation of and functional connectivity between brain regions that mediate task performance.

Adult↗

Functional protein microarrays: just how functional are they?

Arrays of immobilized proteins have been developed for the discovery and characterization of protein functions ranging from molecular recognition to enzymatic activity. The success of these applications is highly dependent upon the maintenance of protein structure and function while in an immobilized state - a largely untested hypothesis. However, the immobilization of functional proteins is not without precedent. Active enzymes have been successfully immobilized for industrial applications for several decades. Furthermore, a survey of recent protein microarray literature reveals that an even wider range of proteins can maintain 'proper' function while immobilized. These reports help to validate the functionality of so-called functional protein microarrays.

DNA-Binding Proteins↗

Evaluation of the effectiveness of treatment with erythropoietin on anemia, cognitive functioning and functions studied by comprehensive geriatric assessment in elderly cancer patients with anemia related to cancer chemotherapy.

The primary aim of the present study was to examine the relationship of changes in hemoglobin levels following recombinant human erythropoietin (rHuEPO) treatment to changes in cognitive functioning studied by Mini Mental State Examination (MMSE) in elderly cancer patients undergoing chemotherapy treatment. The secondary aim was that to assess the relationship of changes in hemoglobin levels following rHuEPO treatment to changes in functions studied by Comprehensive Geriatic Assessment (CGA), such as Activity of Daily Living (ADL), Instrumental Activities of Daily Living (IADL), Geriatric Depression Scale (GDS) and the Mini Nutritional Assessment (MNA). To this end, hemoglobin levels and cognitive functioning were evaluated in a sample of cancer patients prior to the start of chemotherapy treatment and again after 4, 8 and 12 weeks of treatment with chemotherapy plus rHuEPO. Ten elderly patients (mean age 71.4 years) were enrolled. At baseline, enrolled patients had a mean Hb value of 10.3g/dl. After 4 weeks of rHuEPO treatment, Hb values increased significantly (p<0.0001), with a mean increase of 1.2g/dl (range: 0.2-2.1). Remarkably, 8 out of 10 (80%) showed an increase of Hb levels >or=1g/dl in comparison to baseline and therefore were considered responders. At baseline, four patients (40%) showed a moderate cognitive impairment, whilst six patients (60%) showed a normal cognitive function. After 4 weeks of rHuEPO treatment nine patients (90%) showed a significant improvement of cognitive functions in comparison to baseline (p<0.005): eight of them were responders also to rHuEPO in terms of correction of anemia. The Spearman's rank correlation test showed a statistical significant correlation between Hb increase and increase in cognitive functioning assessed by MMSE after 4 weeks (p=0.049), 8 weeks (p=0.044) and 12 weeks (p=0.031) of rHuEPO treatment. Therefore, the findings of this study provide support for the hypothesis that significant increases in hemoglobin over the course of chemotherapy supplemented with rHuEPO administration would be accompanied by significant improvement in cognitive performance over the same interval.

Aged↗

Functional status in rate- versus rhythm-control strategies for atrial fibrillation: results of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) Functional Status Substudy.

OBJECTIVES: The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) functional status substudy aimed to test the hypothesis that functional status is similar in rate-control and rhythm-control strategies. BACKGROUND: Randomized studies, including the AFFIRM study, have failed to demonstrate survival benefits between rate-control and rhythm-control strategies for atrial fibrillation (AF). However, AF may cause functional capacity or cognitive impairment that might justify maintenance of sinus rhythm. METHODS: Investigators of the AFFIRM study enrolled 4,060 patients with AF who required long-term therapy and who were 65 years of age or older or who had another risk factor for stroke or death. New York Heart Association functional class (NYHA-FC) and Canadian Cardiovascular Society Angina Classification were assessed at initial and each follow-up visit. From 22 randomly chosen functional status substudy sites, 245 participants underwent 6-min walk tests and Mini-Mental State Examination (MMSE) at initial, two-month, and yearly visits. Patients were assigned randomly to rate-controlling drugs, allowing AF to persist, or rhythm-controlling antiarrhythmic drugs, to maintain sinus rhythm. RESULTS: The NYHA-FC worsened with time in both rate-control and rhythm-control groups, with no differences between groups. Presence of AF was associated with worse NYHA-FC (p < 0.0001). No differences were observed in Canadian Cardiovascular Society Angina Classification or MMSE scores. Six-minute walk distance improved over time in both study arms. On average, walk distance was 94 feet greater in the rhythm-control group (adjusted p = 0.049). CONCLUSIONS: Modest improvement in 6-min walk distance was noted in the rhythm-control arm. Presence of AF was associated with worse NYHA-FC. No difference in cognitive function was detected.

Aged↗

Estimation of the effective and functional human cortical connectivity with structural equation modeling and directed transfer function applied to high-resolution EEG.

Different brain imaging devices are presently available to provide images of the human functional cortical activity, based on hemodynamic, metabolic or electromagnetic measurements. However, static images of brain regions activated during particular tasks do not convey the information of how these regions are interconnected. The concept of brain connectivity plays a central role in the neuroscience, and different definitions of connectivity, functional and effective, have been adopted in literature. While the functional connectivity is defined as the temporal coherence among the activities of different brain areas, the effective connectivity is defined as the simplest brain circuit that would produce the same temporal relationship as observed experimentally among cortical sites. The structural equation modeling (SEM) is the most used method to estimate effective connectivity in neuroscience, and its typical application is on data related to brain hemodynamic behavior tested by functional magnetic resonance imaging (fMRI), whereas the directed transfer function (DTF) method is a frequency-domain approach based on both a multivariate autoregressive (MVAR) modeling of time series and on the concept of Granger causality. This study presents advanced methods for the estimation of cortical connectivity by applying SEM and DTF on the cortical signals estimated from high-resolution electroencephalography (EEG) recordings, since these signals exhibit a higher spatial resolution than conventional cerebral electromagnetic measures. To estimate correctly the cortical signals, we used a subject's multicompartment head model (scalp, skull, dura mater, cortex) constructed from individual MRI, a distributed source model and a regularized linear inverse source estimates of cortical current density. Before the application of SEM and DTF methodology to the cortical waveforms estimated from high-resolution EEG data, we performed a simulation study, in which different main factors (signal-to-noise ratio, SNR, and simulated cortical activity duration, LENGTH) were systematically manipulated in the generation of test signals, and the errors in the estimated connectivity were evaluated by the analysis of variance (ANOVA). The statistical analysis returned that during simulations, both SEM and DTF estimators were able to correctly estimate the imposed connectivity patterns under reasonable operative conditions, that is, when data exhibit an SNR of at least 3 and a LENGTH of at least 75 s of nonconsecutive EEG recordings at 64 Hz of sampling rate. Hence, effective and functional connectivity patterns of cortical activity can be effectively estimated under general conditions met in any practical EEG recordings, by combining high-resolution EEG techniques and linear inverse estimation with SEM or DTF methods. We conclude that the estimation of cortical connectivity can be performed not only with hemodynamic measurements, but also with EEG signals treated with advanced computational techniques.

Adult↗

The relationship of postural sway to sensorimotor function, functional performance, and disability in the elderly.

OBJECTIVE: To examine the relationship of postural sway to sensorimotor impairment, functional performance, and self-reported disability. DESIGN: Cross-sectional cohort. SETTING: Department of Veterans' Affairs Medical Center. PATIENTS: One hundred community-dwelling elderly unable to climb stairs step over step. MAIN OUTCOME MEASURES: Postural sway (area of ellipse and path length, eyes open and closed), sensorimotor (strength, sensation, range of motion, central processing time), functional performance (functional reach, timed gait, mobility skills, endurance), and disability (MOS-SF36, Falls Efficacy Scale [FES]). RESULTS: Postural sway area measures correlated with sensorimotor measures: (1) During eyes-closed conditions, increased sway occurs in individuals with sensory deficits (p < .05); (2) Sway was positively correlated with tibialis anterior latency (p < .05); (3) Sway area measures increased with increased strength (p < .05). The sway/strength relationship may be explained by week subjects improving their stability by limiting rather than increasing sway. Sway was not significantly correlated with any measures of physical performance. Sway was correlated with some measures of disability: (1) Eyes-closed measures of postural sway were correlated with FES scores (p < .05); (2) Sway was not correlated with the MOS-36 physical functioning question. When controlling for functional measures, eyes-closed measures of sway significantly predicted FES scores (p < .03). CONCLUSIONS: Measures of postural sway are more likely capturing sensorimotor deficits rather than differentiating functional performance abilities, and the relationship between postural sway and self-reported disability is inconsistent.

Activities of Daily Living↗

Lack of an ovarian function influence on the increased adrenal androgen secretion present in women with functional ovarian hyperandrogenism.

OBJECTIVE: To evaluate whether ovarian function might have an influence on the adrenal hyperandrogenism present in patients with functional ovarian hyperandrogenism. DESIGN: Controlled clinical study. SETTING: Tertiary institutional hospital. PATIENT(S): Twenty-nine hirsute women with functional ovarian hyperandrogenism and 12 normal controls. INTERVENTION(S): The ACTH and GnRH tests were performed before and during triptorelin-induced ovarian suppression in patients. The normal women served as controls for the ACTH test. MAIN OUTCOME MEASURE(S): Basal and ACTH-stimulated steroid values. RESULT(S): All patients presented elevated T and free androgen index, which normalized after triptorelin. Patients with functional ovarian hyperandrogenism and adrenal hyperandrogenism, defined by elevated basal DHEAS (n = 10), presented enhanced delta 4-17, 20-lyase activity, which persisted during ovarian suppression. delta 4-17,20-lyase activity was normal in the functional ovarian hyperandrogenism patients without adrenal hyperandrogenism (n = 19). No correlation was observed between the any of the indexes of the adrenal enzymatic activities evaluated and plasma E2 or T. CONCLUSION(S): Increased adrenal delta 4-17,20-lyase activity is present in functional ovarian hyperandrogenism women with adrenal hyperandrogenism. No influence of the excess ovarian androgens or estrogens was found on any of the adrenal enzymatic pathways explored.

Adolescent↗

Functional fingerprints of folds: evidence for correlated structure-function evolution.

Using structural similarity clustering of protein domains: protein domain universe graph (PDUG), and a hierarchical functional annotation: gene ontology (GO) as two evolutionary lenses, we find that each structural cluster (domain fold) exhibits a distribution of functions that is unique to it. These functional distributions are functional fingerprints that are specific to characteristic structural clusters and vary from cluster to cluster. Furthermore, as structural similarity threshold for domain clustering in the PDUG is relaxed we observe an influx of earlier-diverged domains into clusters. These domains join clusters without destroying the functional fingerprint. These results can be understood in light of a divergent evolution scenario that posits correlated divergence of structural and functional traits in protein domains from one or few progenitors.

Adenosine Triphosphate↗

Clock drawing task, mini-mental state examination and cognitive-functional independence measure: relation to functional outcome of stroke patients.

The use of reliable and valid brief cognitive screening instrument for selecting the appropriate candidates for stroke rehabilitation is crucial. Clinicians often face the question which test should be preferred, that will best correlate with functional outcome. The objective of this study was to compare the clock drawing task with other cognitive tests used for the evaluation of discharge functional outcome in elderly stroke patients. We conducted a retrospective chart study including 151 consecutive patients, admitted for inpatient comprehensive rehabilitation following acute stroke. The clock drawing task (CDT), mini-mental state examination (MMSE) and the cognitive-functional independence measure (cognFIM) were used to assess the cognitive status. Functional status outcome was evaluated by the functional independence measure (FIM), using absolute and relative parameters of efficacy and efficiency. Correlation coefficients (Pearson correlation) between the three cognitive tests resulted in r-values ranging from 0.51 to 0.59 (P<0.001). All three tests correlated significantly with motor outcomes. MMSE did not confer additive value to CDT. It is concluded that CDT is similar to mini-mental and both are somewhat better than cognFIM with respect to the evaluation of functional status outcome following stroke. The correlations between the tests as well as the simplicity of administration favor the use of either CDT or MMSE in the initial assessment of elderly stroke patients.

Journal Article↗

The experimental combination of rTMS and fMRI reveals the functional relevance of parietal cortex for visuospatial functions.

We combined repetitive transcranial magnetic stimulation (rTMS) and functional magnetic resonance imaging (fMRI) to investigate the functional relevance of parietal cortex activation during the performance of visuospatial tasks. fMRI provides information about local transient changes in neuronal activation during behavioural or cognitive tasks. Information on the functional relevance of this activation was obtained by using rTMS to induce temporary regional deactivations. We thereby turned the physiological parameter of brain activity into an independent variable controlled and manipulated by the experimenter and investigated its effect on the performance of the cognitive tasks within a controlled experimental design. We investigated cognitive tasks that were performed on the same visual material but differed in the demand on visuospatial functions. For the visuospatial tasks we found a selective enhancement of fMRI signal in the superior parietal lobule (SPL) and a selective impairment of performance after rTMS to this region in comparison to a control group. We could thus show that the parietal cortex is functionally important for the execution of spatial judgements on visually presented material and that TMS as an experimental tool has the potential to interfere with higher cognitive functions such as visuospatial information processing.

Adult↗

Web-based Simulation for Contrast Transfer Function and Envelope Functions.

We have implemented a Web-based simulation program for the contrast transfer function and envelope functions in Java and JavaScript. The simulation provides interactive controls of all the parameters in those functions. In addition to the predefined functions, users can easily define new functions that use any of the parameters in the preset functions. The most useful feature of this new simulation program is the convenient, universal accessibility through Web browsers on any computer platform that supports Java, such as Netscape and Internet Explorer.

Journal Article↗

Functional neck dissection: cure and functional results.

In this study, the cure and functional results of 133 functional neck dissections performed between 1992-1997 in Erciyes University Medical Faculty were evaluated. The overall recurrence rate was three per cent. This rate was 1.4 per cent for elective functional neck dissections and five per cent for curative functional neck dissections. Electromyographic studies showed that there was severe neurogenic deficit in the trapezius muscle of seven patients (12.5 per cent), and in the sternocleidomastoid muscle of 12 patients (21.4 per cent) among 56 randomly selected patients. In all cases, the flow rate and diameter of the internal jugular vein was found to be normal by Doppler ultrasonography. The results of this study showed that functional neck dissection is a reliable technique for obtaining a high cure rate and functional results.

Adult↗

The Range of Impaired Functioning Tool (LIFE-RIFT): a brief measure of functional impairment.

BACKGROUND: The literature documents that functional impairment is associated with affective disorders. Nevertheless, the choice among thorough, yet brief, well-validated assessments of functional impairment is limited. The objective of this study was to evaluate the psychometric properties of a brief scale of functional impairment, the Range of Impaired Functioning Tool (LIFE-RIFT). METHOD: The study sample included subjects who presented with major depressive disorder at intake into the NIMH Collaborative Depression Study (CDS). The LIFE-RIFT is composed of items that are included in the Longitudinal Interval Follow-up Evaluation (LIFE). The reliability and validity were examined using data from LIFE-RIFT assessments conducted at four points in time: 6, 12, 18 and 24 months after intake into the CDS. RESULTS: Cross-sectional one factor models accounted for the covariance structure among the four scale items. A longitudinal factor model, with an invariant factor structure over time, also fitted the data well and indicated that the scale items are measures of one construct, namely functional impairment. The internal consistency reliability of the scale was supported with alpha coefficients ranging from 0.81 to 0.83. The inter-rater reliability intraclass correlation coefficient (ICC) was 0.94. Mixed-effect linear regression models showed that those in episode were significantly more impaired than those in recovery. Furthermore, in analyses of predictive validity, impairment was positively associated with subsequent recurrence and negatively associated with subsequent recovery. CONCLUSIONS: This psychometric evaluation provides empirical support for the reliability and validity of the LIFE-RIFT, a brief measure of functional impairment.

Activities of Daily Living↗