[Translated article] Latarjet procedure for shoulder instability: Implications in the innervation of the subscapularis muscle

INTRODUCTION

Our aim was to describe whether Latarjet's technique affects subscapularis muscle innervation.

MATERIALS AND METHODS

We studied 12 embalmed shoulders. Subscapularis muscle innervation pattern was registered. Dimensions of the subscapularis at the glenohumeral joint line and the nerves entry point were measured. Horizontal distances from the nerves to the glenohumeral joint line as well as vertical ones to the split were measured before and after Latarjet procedure. A safe zone for the split was designed to avoid damage to subscapularis innervation.

RESULTS

Subscapularis muscle is innervated by three principal branches: upper, middle, and inferior subscapularis nerves. No statistical differences were found between innervation distances before and after Latarjet procedure. To perform subscapularis split along the muscle safe zone, two thirds' proportions throughout all the split must be maintained.

CONCLUSIONS

Subscapularis muscle has a triple innervation and was not altered after Latarjet procedure. Therefore, Latarjet technique seems to respect subscapularis muscle innervation if its split is placed through the subscapularis muscle safe zone.

Latarjet procedure for shoulder instability: Implications in the innervation of the subscapularis muscle

INTRODUCTION

Our aim was to describe whether Latarjet's technique affects subscapularis muscle innervation.

MATERIALS AND METHODS

We studied 12 embalmed shoulders. Subscapularis muscle innervation pattern was registered. Dimensions of the subscapularis at the glenohumeral joint line and the nerves entry point were measured. Horizontal distances from the nerves to the glenohumeral joint line as well as vertical ones to the split were measured before and after Latarjet procedure. A safe zone for the split was designed to avoid damage to subscapularis innervation.

RESULTS

Subscapularis muscle is innervated by three principal branches: upper, middle, and inferior subscapularis nerves. No statistical differences were found between innervation distances before and after Latarjet procedure. To perform subscapularis split along the muscle safe zone, two thirds' proportions throughout all the split must be maintained.

CONCLUSIONS

Subscapularis muscle has a triple innervation and was not altered after Latarjet procedure. Therefore, Latarjet technique seems to respect subscapularis muscle innervation if its split is placed through the subscapularis muscle safe zone.

[Translated article] Comparative biomechanical study of two configurations of cemented screws in a simulated proximal humerus fracture fixed with locking plate

INTRODUCTION

Screw tip augmentation with bone cement for fixation of osteoporotic proximal humerus fractures seems to improve stability and to decrease the rate of complications related to implant failure. However, the optimal augmentation combinations are unknown. The aim of this study was to assess the relative stability of two augmentations combinations under axial compression load in a simulated proximal humerus fractures fixed with locking plate.

MATERIAL AND METHODS

A surgical neck osteotomy was created in five pairs of embalmed humeri with a mean age of 74 years (range 46-93 years), secured with a stainless-steel locking-compression plate. In each pair of humeri, on the right humerus were cemented the screws A and E, and in the contralateral side were cemented screws B and D of the locking plate. The specimens were first tested cyclically in axial compression for 6000 cycles to evaluate interfragmentary motion (dynamic study). At the end of the cycling test, the specimens were loaded in compression force simulating varus bending with increasing load magnitude until failure of the construct (static study).

RESULTS

There were no significant differences in interfragmentary motion between the two configurations of cemented screws in the dynamic study (p=0.463). When tested to failure, the configuration of cemented screws in lines B and D demonstrated higher compression load to failure (2218N vs. 2105, p=0.901) and higher stiffness (125N/mm vs. 106N/mm, p=0.672). However, no statistically significant differences were reported in any of these variables.

CONCLUSIONS

In simulated proximal humerus fractures, the configuration of the cemented screws does not influence the implant stability when a low-energy cyclical load is applied. Cementing the screws in rows B and D provides similar strength to the previously proposed cemented screws configuration and could avoid complications observed in clinical studies.

Antibiotics has more impact on mortality than other early goal-directed therapy components in patients with sepsis: An instrumental variable analysis

PURPOSE

To estimate the effect of each of the EGDT components, as well as of the antibiotics, on length-of-stay and mortality.

METHODS

Prospective cohort in three hospitals. Adult patients admitted by the Emergency Rooms (ER) with infection and any of systolic blood pressure < 90 mmHg or lactate >4 mmol/L. An instrumental analysis with hospital of admission as the instrumental variable was performed to estimate the effect of each intervention on hospital mortality and secondary outcomes.

RESULTS

Among 2587 patients evaluated 884 met inclusion criteria, with a hospital mortality rate of 17% (n = 150). In the instrumental analysis, the only intervention associated with an absolute reduction in mortality (21%) was the use of antibiotics in the first 3 h. In patients with lactate values ≥4 mmol/L in the ER, a non-decrease of at least 10% at six hours was independently associated with mortality (OR = 3.1; 95%CI = 1.5-6.2).

CONCLUSIONS

Among patients entering ER with infection and shock or hypoperfusion criteria, the use of appropriate antibiotics in the first 3 h is the measure that has the greatest impact on survival. In addition, among patients with hyperlactatemia >4 mmol/L, the clearance of >10% of lactate during resuscitation is associated with better outcomes.

Spontaneous Separation in Idiopathic Vitreomacular Traction Syndrome Associated with Contralateral Full-Thickness Macular Hole

Purpose

Vitreomacular traction syndrome (VMTS) and full-thickness macular hole are two different well-known entities that on follow-up may be subjected to clinical modifications. Precisely, a spontaneous separation of idiopathic VMTS occurred in three eyes of three patients relieving in addition traction of the posterior hyaloid that had led also to a focal macular pigment epithelium detachment (RPE). An association to a full-thickness macular hole was observed in the contralateral eye of one of the patients.

Methods

This is a retrospective study of three patients evaluated with fluorescein angiography and documented with optical coherence tomography using the Stratus (OCT) model 3000, with scans analysis and protocols analysis, measuring the size and shape of vitreomacular adhesions, macular thickness changes before and after the spontaneous separation of the fractional posterior hyaloid adhesion. In addition, the vitreous was evaluated with contact lens slit lamp biomicroscopy and ultrasound. The associated contralateral macular hole in one of the patients was surgically treated.

Results

Two of the three eyes with spontaneous separation of the VMTS recovered 20/25 central visual acuity; the other eye maintained the initial 20/50 visual acuity. The treated macular hole recovered 20/100 corrected visual acuity.

Conclusions

Spontaneous separation of posterior hyaloid is a possible outcome during follow-up of idiopathic VMTS that can be well evaluated and documented with OCT while macular fluorescein angiography may be silent in cases like these presently reported. Central vision recovery can be excellent following the spontaneous separation, which releases anterior-posterior traction including on the retinal pigment epithelium and decreases macular thickness as measured with OCT. Therefore, regarding management, the indication for vitrectomy should be delayed awaiting the spontaneous release of vitreomacular traction in 4 to 6 months. The association between idiopathic VMTS in one eye and full-thickness macular hole in the opposite eye of one patient is an important pathophysiologic consideration.

The effectiveness of interventions to treat hypothalamic obesity in survivors of childhood brain tumours: a systematic review

BACKGROUND

Survivors of childhood brain tumours (SCBT) are at risk of type 2 diabetes and cardiovascular diseases. Obesity is a major driver of cardiometabolic diseases in the general population, and interventions that tackle obesity may lower the risk of these chronic diseases. The goal of this systematic review was to summarize current evidence for the presence of interventions to manage obesity, including hypothalamic obesity, in SCBT.

METHODS

The primary outcome of this review was the body mass index z-score change from baseline to the end of the intervention and/or follow-up. Literature searches were conducted in PsycINFO, CINAHL, the Cochrane Library, Medline, SPORTDiscus, EMBASE and PubMed. Two reviewers completed study evaluations independently.

RESULTS

Eleven publications were included in this systematic review (lifestyle intervention n = 2, pharmacotherapy n = 6 and bariatric surgery n = 3). While some studies demonstrated effectiveness of interventions to manage obesity in SCBT and alter markers of obesity and cardiometabolic risk, the evidence base was limited and of low quality, and studies focused on hypothalamic obesity. We conclude that there is urgent need to conduct adequately powered trials of sufficient duration, using existing and novel therapies to manage obesity, reduce the burden of cardiometabolic disorders and improve outcomes in SCBT.

Natural disaster management: experience of an academic institution after a 7.8 magnitude earthquake in Ecuador

OBJECTIVES

This case study describes the implementation of an academic institution's disaster management plan.

STUDY DESIGN

Case study.

METHODS

USFQ's Medical School developed a six-phase disaster relief plan consisting of: induction, establishing a base camp, crisis management and mental health aid, creation of multidisciplinary teams and multi-agency teams, and reconstruction. Each phase uses a community-oriented approach to foster survivor autonomy and recovery.

RESULTS

Our methodology facilitated the successful implementation of multidisciplinary interventions to manage the earthquake's aftermath on the personal, community and regional levels, treated and prevented psychological and physical morbidity among survivors and promoted healthy living conditions and independence.

CONCLUSIONS

A multidisciplinary response team that addresses medical needs, mental health, education, food, nutrition and sanitation is highly effective in contributing to timely, effective relief efforts. The short- and long-term solutions we describe could be applicable to other academic centres' interventions in future disaster scenarios around the world.

Enhanced product selectivity promoted by remote metal coordination in acceptor-free alcohol dehydrogenation catalysis

A bimetallic [Ir³⁺]₂ complex was synthesized based on a bridging 1,2,3-triazole ligand that coordinates to one Cp*Ir unit as N,N-bidentate chelate, and to the other as a C,C-bidentate ligand.

Effect of antenatal betamethasone administration on rat cerebellar expression of type la metabotropic glutamate receptors (mGluRla) and anxiety-like behavior in the elevated plus maze

Preclinical studies indicate that endogenous or exogenous glucocorticoids acting during the pre- or postnatal periods produce a significant Purkinje cell dendritic atrophy, especially during late postnatal ages. The present authors hypothesized that the underlying sub- strate that may contribute in part to this morphological change is the under-expression of the metabotropic glutamate la receptor (mGluRl a) because its expression is correlated with Purkinje cell dendritic outgrowth. Therefore, in the current study, they analyzed the impact of antenatal betamethasone on the immunoreactive expression of the mGluR 1 a and on anxiety-like behavior in the elevated plus maze (EPM). Pregnant rats were randomly divided into two experimental groups: control (CONT) and betamethasone-treated (BET). At gestational day 20 (G20), BET rats were subcutaneously injected with a solution of 170 μg.kg(-1) of betamethasone, and CONT animals received a similar volume of saline. At postnatal days 22 (P22) and P52, BET and CONT offspring were evaluated behaviorally in the EPM, and their cerebella were immunohistochemically processed. Contrary to the uthors' expected results, animals that were prenatally treated with a single course of betamethasone did not exhibit under-expression of mGluRl a or behavioral changes consistent with anxiety-like behaviors.

Botulinum toxin type A and myofascial pain syndrome: a retrospective study of 301 patients

BACKGROUND

Botulinum toxin type A (BTX-A) intramuscular injections have been used for the treatment of myofascial pain syndrome (MPS), although its efficacy remains still unknown and its safety is controversial.

OBJECTIVE

To analyze the effectiveness and safety of the injection protocol for BTX-A in the shoulder-scapular and lumbar-pelvic girdles combined with physiotherapy in patients with primary and secondary MPS.

METHODS

Retrospective descriptive study including 301 medical files of patients with persistent MPS. Positive responses to treatment were considered to be a satisfactory level of effectiveness with 50% pain relief or a fully satisfactory level of effectiveness at 80%.

RESULTS

Overall, 58.1% of patients obtained a positive result at 6 months. Differences in effectiveness were found between primary MPS (82.9% of patients) and secondary MPS (54.9%; p=0.002). In patients with secondary MPS, differences in effectiveness arose based on pathologies associated with MPS (p=0.03). In 23.9% of cases, mild and temporary adverse effects were observed post-infiltration.

CONCLUSIONS

BTX-A injections and physiotherapy is an alternative to conventional treatment which should be considered when treating refractory MPS. Nonetheless, the differences in effectiveness based on diagnosis suggest the need to clarify the criteria used to select patients with MPS in future clinical trials and applications.

On the use of metal purine derivatives (M=Ir, Rh) for the selective labeling of nucleosides and nucleotides

The reactions of neutral or cationic IrIII and RhIII derivatives of phenyl purine nucleobases with unsymmetrical alkynes produce new metallacycles in a predictable manner, which allows for the incorporation of either photoactive (anthracene or pyrene) or electroactive (ferrocene) labels in the nucleotide or nucleoside moiety. The reported methodology (metalation of the purine derivative and subsequent marker insertion) could be used for the postfunctionalization and unambiguous labeling of oligonucleotides.

The beneficial effects of combining pharmacological and psychosocial treatment on remission and functional outcome in outpatients with schizophrenia

OBJECTIVE

The effects of pharmacological and psychosocial treatment on remission and the functional outcome in outpatients with schizophrenia were evaluated. Remission was assessed according to the criteria proposed by the Remission in Schizophrenia Working group and psychosocial functioning according to the Global Assessment of Functioning with a score > 60. Functional outcome was the result of these two variables.

METHOD

One hundred fifty two patients were randomized to receive either, antipsychotic treatment as usual (TAU) or social skills training and family psychoeducation in addition to TAU. A final sample of 119 patients: n = 68 in the social skills training group, and n = 51 in the TAU group completed the study protocol. Patients were assessed at baseline and at 6-month follow-up.

RESULTS

At the end of the study, 80% of the patients fulfilled the criteria for symptomatic remission: 62 patients (91.2%) in the social skills training group in contrast to 34 patients (66.7%) in the TAU group. Functional improvement criteria were accomplished by 41 patients (34.5%) at the endpoint of the study. Forty of these patients (58.8%) belonged to social skills training and one patient to customary treatment (χ(2) = 41.7, df 1, p < 0.001) and when criteria for symptomatic remission and functional improvement were combined, 39 patients (97.5%) of the social skills training group and one patient (1.9%) of the customary treatment group achieved functional outcome.

CONCLUSION

The results emphasize the need for psychosocial interventions as conjoint to pharmacological treatment to improve functional outcome in schizophrenia patients.

Mono- and dinuclear osmium N,N'-di- and tetraphenylbipyridyls and extended bipyridyls. Synthesis, structure and electrochemistry

The efficient synthesis of mono- and dinuclear Os(IV) bipyridyl complexes is reported. These compounds show a two-step oxidation process leading to notable structural changes, which are reflected in their emission properties. During the second oxidation process a tetracation with a hydride-dihydrogen structure (instead of a trihydride) is formed. This results in a significant bathochromic shift of the emission band, accompanied by a moderate increase in intensity.

Medical case management after laminectomy or craniotomy: do all patients benefit from admission to the intensive care unit?

To define severity of illness to identify most effectively patients for whom admission to the intensive care unit (ICU) is unnecessary, the authors performed a retrospective cost-effectiveness analysis. The authors studied the records of 113 patients who were admitted to the ICU after undergoing laminectomy (or other spinal cord surgery) or craniotomy for removal of neoplasm; the Acute Physiology and Chronic Health Evaluation III prognostic system had identified these patients as having a 10% or less risk of requiring intervention while in the ICU. No patient required active intervention during a mean stay of 3.26 days in the ICU. Combined use of a "step-down" postoperative care unit and ICU can optimize allocation of medical resources while providing high-quality care for some neurosurgical patients who are at low risk of requiring postoperative intervention.

Real-time G-protein-coupled receptor imaging to understand and quantify receptor dynamics

Understanding the trafficking of G-protein-coupled receptors (GPCRs) and their regulation by agonists and antagonists is fundamental to develop more effective drugs. Optical methods using fluorescent-tagged receptors and spinning disk confocal microscopy are useful tools to investigate membrane receptor dynamics in living cells. The aim of this study was to develop a method to characterize receptor dynamics using this system which offers the advantage of very fast image acquisition with minimal cell perturbation. However, in short-term assays photobleaching was still a problem. Thus, we developed a procedure to perform a photobleaching-corrected image analysis. A study of short-term dynamics of the long isoform of the dopamine type 2 receptor revealed an agonist-induced increase in the mobile fraction of receptors with a rate of movement of 0.08 μm/s For long-term assays, the ratio between the relative fluorescence intensity at the cell surface versus that in the intracellular compartment indicated that receptor internalization only occurred in cells co-expressing G protein-coupled receptor kinase 2. These results indicate that the lateral movement of receptors and receptor internalization are not directly coupled. Thus, we believe that live imaging of GPCRs using spinning disk confocal image analysis constitutes a powerful tool to study of receptor dynamics.

[Brain oscillations: pathophysiological and potentially therapeutic role in some neurological and psychiatric diseases]

The terms "oscillations" or "oscillatory activity" are frequently used not only to define the rhythmic fluctuations of the postsynaptic potentials of a neuronal group (local field potentials) or a cortical region (EEG, MEG), but also to indicate the rhythmic discharge pattern of action potentials from a neuron or a small group of neurons. Oscillatory activity makes possible the synchronization of different neuronal groups from nearby or distant cortical regions that participate in the same motor, sensory or cognitive task. The presence of oscillatory activity is usually associated to the existence of synchronization, but both phenomena are not necessarily always equivalent. Abnormalities of oscillatory activities or synchronization within or between different brain structures have been described in several neurological and psychiatric diseases; these abnormalities might play a relevant pathophysiological role in Parkinson's disease (and other movement disorders), schizophrenia or epilepsy. This review discusses all these aspects, with emphasis on their potential role both as a basic mechanism in brain function and as a pathophysiological substrate for some of the symptoms and signs observed in several diseases.

Health education home-based program in females with fibromyalgia: a pilot study

The objective of this study was to assess the long- and short-term effects of a multimodal program, specifically designed to be carried out by fibromyalgia syndrome (FMS) patients themselves, after a 12-week period of learning. Thirty female FMS patients volunteered for the study. The learning phase consisted on twelve weekly sessions of an hour, combining muscular resistance and flexibility exercises with techniques of breathing and relaxing, plus a half-hour incentive physiotherapy session. Flexibility, illness impact and pain were assessed at the beginning of the study, at the end of the learning phase and six months afterwards (follow-up). Twenty-one patients completed the programme. At the end of the learning phase, the improvement in the patients' physical condition was significant, as was the impact of the illness. Thirty-three percent of the patients continued training during the follow-up period and kept up the improvements achieved. The self-controlled multimodal programme was efficient in improving flexibility and reducing the impact of the illness in women fibromyalgia patients. However, adherence was poor when patients had to exercise on their own.

Functional modularity of background activities in normal and epileptic brain networks

We analyze the connectivity structure of weighted brain networks extracted from spontaneous magnetoencephalographic signals of healthy subjects and epileptic patients (suffering from absence seizures) recorded at rest. We find that, for the activities in the 5-14 Hz range, healthy brains exhibit a sparse connectivity, whereas the brain networks of patients display a rich connectivity with a clear modular structure. Our results suggest that modularity plays a key role in the functional organization of brain areas during normal and pathological neural activities at rest.

Complex modular structure of large-scale brain networks

Modular structure is ubiquitous among real-world networks from related proteins to social groups. Here we analyze the modular organization of brain networks at a large scale (voxel level) extracted from functional magnetic resonance imaging signals. By using a random-walk-based method, we unveil the modularity of brain webs and show modules with a spatial distribution that matches anatomical structures with functional significance. The functional role of each node in the network is studied by analyzing its patterns of inter- and intramodular connections. Results suggest that the modular architecture constitutes the structural basis for the coexistence of functional integration of distant and specialized brain areas during normal brain activities at rest.

Aromatic diosmatricyclic nitrogen-containing compounds

Aromatic diosmatricyclic nitrogen-containing compounds are prepared from Os(VI) complex OsH6(PiPr3) by double 1,3-C-H bond activation of aromatic six-membered cycles with imino substituents meta disposed.

Expression of TGF-betas in the embryonic nervous system: analysis of interbalance between isoforms

Transforming growth factor-beta (TGF-beta) is a family of growth factors with essential and multiple roles during embryonic development. In mammals, three isoforms (TGF-beta1, TGF-beta2, TGF-beta3) have been described. In the nervous system, the presence of TGF-beta1 has remained undetectable in other structures than meninges and choroids plexus, while TGF-beta2 and TGF-beta3 were considered as the neural members of the family. In the present study, we have analysed the expression pattern of the three isoforms in the neural tube, brain, and spinal cord during development in both mouse and chicken. The data reveal specific patterns for each isoform. This work also shows that both TGF-beta1 and TGF-beta3 are expressed in neural crest cells. In addition, we demonstrate the existence of interbalance between TGF-beta1 and TGF-beta3 with possible functional implications, which, together with the expression of TGF-beta1 in the CNS, represents one of the most important contributions of this work.

The relationship between linear type traits and fertility traits in high-yielding dairy goats

Reproductive data collected from 13 medium-size goat farms in central Mexico (582 goats), were used to investigate if linear type traits influenced reproductive performance of high-yielding dairy goats. Data were analysed using multiple stepwise forward logistic regressions. Goats with the higher scores for strength were 1.43 times more likely (p < 0.05) to have larger litters (1.49 vs 1.39) than goats with lower strength. Goats approaching level rump angles were 1.68 times more likely (p < 0.01) to have larger litters, compared with goats with extremely sloped rump angles (1.48 vs 1.37). Goats with rear legs nearly straight (posty) in hock tended (p < 0.08) to presented larger litters than goats with rear legs slightly angled (sickled) in hock (1.49 vs 1.38). Less pronounced rump angle was favourable associated (p < 0.05) with litter weight (4.88 vs 4.53 kg) compared with goats with low pin bones. Goats with poorer udder texture were 1.42 more likely (p < 0.05) to have heavier litters than goats with good udder texture. Goats with faulty mammary system tended (p < 0.07) to have heavier litters than goats with good mammary system. Increasing udder height was associated (p < 0.05) with increasing number of services per conception. Goats with good fore udder attachment and non-refined heads were at reduced risk (p < 0.05) for stillbirths. Goats with stronger median ligament were 65% less likely (p < 0.05) to lose their foetuses than those with looser udder support. Our findings indicate that a greater litter size and litter weight is expected in goats as rump angle becomes less sloped. This study showed that a relationship exists between strength of goats and litter size, and that some traits linked to high milk yield were antagonist to some reproductive traits.

Dynamic small-world behavior in functional brain networks unveiled by an event-related networks approach

There is growing interest in studying the role of connectivity patterns in brain functions. In recent years, functional brain networks were found to exhibit small-world properties during different brain states. In previous studies, time-independent networks were recovered from long time periods of brain activity. In this paper, we propose an approach, the event-related networks, that allows one to characterize the dynamical evolution of functional brain networks in time-frequency space. We illustrate this approach by characterizing connectivity patterns in magnetoencephalographic signals recorded during a visual stimulus paradigm. When compared with equivalent random and regular networks, the results reveal that functional connectivity varies with time and frequency during the processing of the stimulus, while maintaining a small-world structure. This approach may provide insights into the connectivity of other complex and spatially extended nonstationary systems.

Oscillatory changes related to the forced termination of a movement

OBJECTIVE

Stimulus-induced movements are accompanied by a definite pattern of oscillatory changes, that include a frontal 15 Hz synchronization, a central peri-movement desynchronization, and a contralateral beta rebound after the movement. Our aim was to study the oscillatory changes related to the forced termination of a single complex motor program (signature) and compare them with those observed after the normal termination of the movement.

METHODS

Fifty-eight reference-free EEG channels were analyzed in 10 healthy subjects. A 2000 Hz tone (S1, go signal) indicated the subject to begin to write his/her complete signature. A second 2000 Hz tone 0.8 s afterwards (50% probability: S2, stop signal) indicated the subject to stop immediately. Movement-related energy changes were evaluated by means of time-frequency (Gabor) transforms.

RESULTS

A frontal 15 Hz synchronization was observed after S1, but not after S2. The amplitude of the post-movement beta increase was significantly lower when the movement was abnormally terminated (p=0.005), while the peri-movement decrease was similar.

CONCLUSIONS

The forced termination of a motor program reduces significantly the amplitude of the post-movement beta increment, conserving its temporal pattern. Also, the presence of the 15 Hz frontal synchronization only after S1, together with the results of previous studies, suggests that the frontal mechanisms involved in go/no go and stop signals are very different.

SIGNIFICANCE

Our results indicate that the beta rebound is an active process, independent of the peri-movement beta decrease, which is influenced by how the movement is terminated.

Relationship between aerobic fitness and quality of life in female fibromyalgia patients

Objective: To determine whether there is a direct link between quality of life and aerobic capacity among female fibromyalgia patients.

Design: Cross-section study.

Setting: University of León.

Subjects: Twenty-nine women belonging to the León Fibromyalgia and Chronic Fatigue Association.

Main measurements: Aerobic capacity and quality of life were measured by means of the Six-Minute Walk Test and the Fibromyalgia Impact Questionnaire. Outcome measures included heart rate and rate of perceived fatigue and dypsnoea.

Results: The average distance walked was 432.8 (61.2) m and the total average Fibromyalgia Impact Questionnaire score was 47.5 (18.9). Only item 1 of the Fibromyalgia Impact Questionnaire, physical function, showed any statistically significant link with the distance walked, which had no statistically significant relationship with any of the variables studied.

Conclusion: The physical fitness of women with fibromyalgia, as determined by the Six-Minute Walk Test and the Fibromyalgia Impact Questionnaire, has no direct relation with quality of life as the patients perceive it.

Chirp-evoked potentials in the awake and anesthetized rat. A procedure to assess changes in cortical oscillatory activity

Steady-state potentials are oscillatory responses generated by rhythmic stimulation of a sensory pathway. The frequency of the response, which follows the frequency of stimulation and potentially indicates the preferential working frequency of the auditory neural network, is maximal at a stimulus rate of 40 Hz for auditory stimuli in humans, but may be different in other species. Our aim was to explore the responses to different frequencies in the rat. The stimulus was a tone modulated in amplitude by a sinusoid with linearly-increasing frequency from 1 to 250 Hz ("chirp"). Time-frequency transforms were used for response analysis in 12 animals, awake and under ketamine/xylazine anesthesia. We studied whether the responses were due to increases in amplitude or to phase-locking phenomena, using single-sweep time-frequency transforms and inter-trial phase analysis. A progressive decrease in the amplitude of the response was observed from the maximal values (around 15 Hz) up to the limit of the test (250 Hz). The high-frequency component was mainly due to phase-locking phenomena with a smaller amplitude contribution. Under anesthesia, the amplitude and phase-locking of lower frequencies (under 100 Hz) decreased, while the phase-locking over 200 Hz increased. In conclusion, amplitude-modulation following responses differ between humans and rats in response range and frequency of maximal amplitude. Anesthesia with ketamine/xylazine modifies differentially the amplitude and the phase-locking of the responses. These findings should be taken into account when assessing the changes in cortical oscillatory activity related to different drugs, in healthy rodents and in animal models of neurodegenerative diseases.

Sequential measurements of procalcitonin levels in diagnosing ventilator-associated pneumonia

The utility of procalcitonin levels to improve the accuracy of clinical and microbiological parameters in diagnosing ventilator-associated pneumonia (VAP) was evaluated. Sequential measurement of procalcitonin and C-reactive protein levels and the calculation of the simplified Clinical Pulmonary Infection Scores (CPIS) were performed in 44 patients mechanically-ventilated for >48 h with neither active infection for the duration or suspicion of VAP. Patients who developed extrapulmonary infection were excluded. In total, 20 cases were suspected of having VAP and diagnosis was microbiologically confirmed in nine. In patients with confirmed VAP, procalcitonin levels were higher than in those without VAP. C-reactive protein levels and CPIS were lower in patients without suspected VAP, but could not discriminate confirmed and nonconfirmed suspicion of VAP. The best sensitivity and specificity (78 and 97%, respectively) corresponded to procalcitonin. The CPIS resulted in the same sensitivity, but had a lower specificity (80%). C-reactive protein had the worst sensitivity (56%), but a good specificity (91%). A CPIS >or=6 combined with serum levels of procalcitonin >or=2.99 ng.mL(-1) did not improve the sensitivity (67%), but resulted in 100% specificity. Procalcitonin might be useful in the diagnosis of ventilator-associated pneumonia. Combined values of Clinical Pulmonary Infection Scores and procalcitonin below the cut-off points excluded false-positive diagnoses of ventilator-associated pneumonia.

Topography of Cortical Activation Differs for Fundamental and Harmonic Frequencies of the Steady-State Visual-Evoked Responses. An EEG and PET H215O Study

In humans, visual flicker stimuli of graded frequency (2-90 Hz) elicit an electroencephalographic (EEG) steady-state visual-evoked response (SSVER) with the same fundamental frequency as the stimulus and, in addition, a series of harmonic responses. The fundamental component of the SSVER is generated by increased synaptic activity in primary visual cortex (V1). We set out to determine the cortical origin of the harmonic responses in humans. For this purpose, we recorded the SSVERs at 5 different frequencies (5, 10, 15, 25, and 40 Hz) and measured regional cerebral blood flow (rCBF) with positron emission tomography-H(2)(15)O at rest and during visual stimulation at the same frequencies. The rCBF contrast weighted by the amplitude of the SSVERs first harmonics showed activation of a swath of cortex perpendicular to V1, including mostly the inferior half of the parieto-occipital sulcus. This area overlapped minimally with the primary visual cortex activated by the fundamental frequency. A different method, estimating EEG cortical source current density with low-resolution brain electromagnetic tomography, gave the same results. Our finding suggests that the inferior portion of the banks of the parieto-occipital sulci contains association visual cortex involved in the processing of stimuli that can be as simple as a flickering light source.