Unspooling the Thread: VIP Interneurons Linked With Autism Spectrum Disorder Behaviors but Not Seizures in Dravet Syndrome

VIP Interneuron Impairment Promotes In Vivo Circuit Dysfunction and Autism-Related Behaviors in Dravet Syndrome Goff KM, Liebergall SR, Jiang E, Somarowthu A, Goldberg EM. Cell Rep . 2023;42(6):112628. doi:10.1016/j.celrep.2023.112628 Dravet syndrome (DS) is a severe neurodevelopmental disorder caused by loss-of-function variants in SCN1A, which encodes the voltage-gated sodium channel subunit Nav1.1. We recently showed that neocortical vasoactive intestinal peptide interneurons (VIP-INs) express Nav1.1 and are hypoexcitable in DS (Scn1a+/-) mice. Here, we investigate VIP-IN function at the circuit and behavioral level by performing in vivo 2-photon calcium imaging in awake wild-type (WT) and Scn1a+/- mice. VIP-IN and pyramidal neuron activation during behavioral transition from quiet wakefulness to active running is diminished in Scn1a+/- mice, and optogenetic activation of VIP-INs restores pyramidal neuron activity to WT levels during locomotion. VIP-IN selective Scn1a deletion reproduces core autism-spectrum-disorder-related behaviors in addition to cellular- and circuit-level deficits in VIP-IN function, but without epilepsy, sudden death, or avoidance behaviors seen in the global model. Hence, VIP-INs are impaired in vivo, which may underlie non-seizure cognitive and behavioral comorbidities in DS.

Effect of the historic Spanish heatwave over glycemic control in adult patients with type 1 diabetes

AIM

To evaluate the effect of the historic Spanish heatwave (9th-26th July 2022) over glycemic control in adults with type 1 diabetes (T1D).

METHODS

Cross-sectional retrospective analysis of adult patients with T1D in Castilla-La Mancha (south-central Spanish region) using intermittently scanned continuous glucose monitoring (isCGM) during and after the heatwave. Primary outcome was change in time in range (TIR) 3.0-10 mmol/L (70-180 mg/dL) of interstitial glucose in the two weeks following the heatwave.

RESULTS

A total of 2701 T1D patients were analyzed. We detected a TIR reduction of 4.0 % (95 % CI -3.4, -4.6; P < 0.001) in the two weeks following the heatwave. Patients in the highest daily scan frequency quartile (>13 scans/day) during the heatwave showed the greatest deterioration in TIR after it concluded (-5.4 % [95 % CI -6.5, -4.3; P < 0.001]). The percentage of patients meeting all the recommendations of the International Consensus of Time in Range was greater during the heatwave than after it ended (10.6 % vs. 8.4 %, P < 0.001).

CONCLUSIONS

Adults with T1D had better glycemic control during the historic Spanish heatwave compared to the following period.

That’s a Wrap: Could Controlling Activity-Regulated Myelination Prevent Absence Seizures?

[Box: see text]

Forebrain epileptiform activity is not required for seizure-induced apnea in a mouse model of Scn8a epilepsy

Sudden unexpected death in epilepsy (SUDEP) accounts for the deaths of 8-17% of patients with epilepsy. Although the mechanisms of SUDEP are essentially unknown, one proposed mechanism is respiratory arrest initiated by a convulsive seizure. In mice, we have previously observed that extended apnea occurs during the tonic phase of seizures. Although often survived, tonic seizures became fatal when breathing did not immediately recover postictally. We also found that respiratory muscles were tonically contracted during the apnea, suggesting that muscle contraction could be the cause of apnea. In the present study, we tested the hypothesis that pyramidal neurons of the motor cortex drive motor units during the tonic phase, which produces apnea. Mice harboring the patient-derived N1768D point mutation of an Scn8a allele were crossed with transgenic mice such that inhibitory Designer Receptors Exclusively Activated by Designer Drugs (DREADD) receptors were selectively expressed in excitatory forebrain neurons. We then triggered audiogenic and hippocampal (HC) stimulated seizures under control conditions and when excitatory forebrain neurons were inhibited with the synthetic ligand Clozapine-N-Oxide (CNO). We found that inhibition with CNO was sufficient to increase seizure threshold of HC stimulated, but not audiogenic, seizures. In addition, regardless of seizure type, CNO nearly eliminated epileptiform activity that occurred proximal to the tonic phase; however, the seizure behaviors, notably the tonic phase and concomitant apnea, were unchanged. We interpret these results to indicate that while cortical neurons are likely critical for epileptogenesis and seizure initiation, the behavioral manifestations of tonic seizures are generated by neural circuitry in the mid- and/or hindbrain.

Identification of Resistance to Exogenous Thyroxine in Humans

Background: Thyroxine (T4) to triiodothyronine (T3) deiodination in the hypothalamus/pituitary is mediated by deiodinase type-2 (D2) activity. Dio2^(-/-) mice show central resistance to exogenous T4. Patients with resistance to exogenous thyroxine (RETH) have not been described. The aim of this study was to identify hypothyroid patients with thyrotropin (TSH) unresponsiveness to levothyroxine (LT4) and to characterize the clinical, hormonal, and genetic features of human RETH. Methods: We investigated hypothyroid patients with elevated TSH under LT4 treatment at doses leading to clinical and/or biochemical hyperthyroidism. TSH and free T4 (fT4) were determined by chemiluminescence, and total T4, T3, and reverse T3 (rT3) by radioimmunoassay. TSH/fT4 ratio at inclusion and T3/T4, rT3/T4, and T3/rT3 ratios at follow-up were compared with those from patients with resistance to thyroid hormone (RTH) due to thyroid hormone receptor-β (THRB) mutations. DIO2, including the Ala92-D2 polymorphism, selenocysteine binding protein 2 (SECISBP2), and THRB were fully sequenced. Results: Eighteen hypothyroid patients (nine of each sex, 3-59 years) treated with LT4 showed elevated TSH (15.5 ± 4.7 mU/L; reference range [RR]: 0.4-4.5), fT4 (20.8 ± 2.4 pM; RR: 9-20.6), and TSH/fT4 ratio (0.74 ± 0.25; RR: 0.03-0.13). Despite increasing LT4 doses from 1.7 ± 1.0 to 2.4 ± 1.7 μg/kg/day, TSH remained elevated (6.9 ± 2.7 mU/L). Due to hyperthyroid symptoms, LT4 doses were reduced, and TSH increased again to 7.9 ± 3.2 mU/L. In the euthyroid/hyperthyrotropinemic state, T3/T4 and T3/rT3 ratios were decreased (9.2 ± 2.4, RR: 11.3-15.3 and 2.5 ± 1.4, RR: 7.5-8.5, respectively) whereas rT3/T4 was increased (0.6 ± 0.2; RR: 0.43-0.49), suggesting reduced T4 to T3 and increased T4 to rT3 conversion. These ratios were serum T4-independent and were not observed in RTH patients. Genetic testing was normal. The Ala92-D2 polymorphism was present in 7 of 18 patients, but the allele dose did not correlate with RETH. Conclusions: Human RETH is characterized by iatrogenic thyrotoxicosis and elevated TSH/fT4 ratio. In the euthyroid/hyperthyrotropinemic state, it is confirmed by decreased T3/T4 and T3/rT3 ratios, and elevated rT3/T4 ratio. This phenotype may guide clinicians to consider combined T4+T3 therapy in a targeted fashion. The absence of germline DIO2 mutations suggests that aberrant post-translational D2 modifications in pituitary/hypothalamus or defects in other genes regulating the T4 to T3 conversion pathway could be involved in RETH.

Frailty, Falls and Osteoporosis: Learning in Elderly Patients Using a Theatrical Performance in the Classroom

OBJECTIVE

To ascertain the usefulness of a simulated clinical scene with actors in the classroom (theatrical performance) as a teaching tool for the management of falls and their related injuries.

DESIGN

Experimental design of two related groups.

SETTING

Spain.

PARTICIPANTS

A group of 12 students attended a seminar in which the approach to a clinical case was made using a simulated scene with actors in the classroom (scene group); a non-scene group of 34 students attended the seminar, without a theatrical performance (the same clinical case was read and presented in a traditional manner, oral presentation).

MEASUREMENTS

Before and after the seminar, students answered a questionnaire [five questions on theoretical knowledge of falls and osteoporosis (score 0-10) and two on subjective learning perception (linear scale: 0-10) (score 0-20)]. In the scene group were two further questions included at the end on their opinion of the scene and on the seminar overall.

RESULTS

Both groups significantly improved in all questionnaire scores after the seminar (p=0.001). The scene group had a greater rise in mean points of the questionnaire before and after the seminar than the non-scene group: theoretical knowledge [3.81±1.69 versus 2.75±1.33 (p=0.033)], subjective questions [6.08±4.10 versus 4.97±2.24 (p=0.247)], and the questionnaire overall [9.89±4.98 versus 7.72±2.66 (p=0.060)]. The scene group had a very good opinion of the usefulness of the scene and of the overall opinion of the seminar: 9.08±0.95 and 9.41±0.79.

CONCLUSIONS

Theatrical performance in the classroom seems to promote better learning than classic oral presentation, providing qualitative value by adding creativity and different approaches to the teaching of medicine.

Optimized ultrasonic attenuation measures for non-homogeneous materials

In this paper the study of frequency-dependent ultrasonic attenuation in strongly heterogeneous materials is addressed. To determine the attenuation accurately over a wide frequency range, it is necessary to have suitable excitation techniques. Three kinds of transmitted signals have been analysed, grouped according to their bandwidth: narrowband and broadband signals. The mathematical formulation has revealed the relation between the distribution of energy in their spectra and their immunity to noise. Sinusoidal and burst signals have higher signal-to-noise ratios (SNRs) but need many measurements to cover their frequency range. However, linear swept-frequency signals (chirp) improve the effective bandwidth covering a wide frequency range with a single measurement and equivalent accuracy, at the expense of a lower SNR. In the case of highly attenuating materials, it is proposed to use different configurations of chirp signals, enabling injecting more energy, and therefore, improving the sensitivity of the technique without a high time cost. Thus, if the attenuation of the material and the sensitivity of the measuring equipment allows the use of broadband signals, the combination of this kind of signal and suitable signal processing results in an optimal estimate of frequency-dependent attenuation with a minimum measurement time.

Characterization of the complexity in short oscillating time series: An application to seismic airgun detonations

Extracting frequency-derived parameters allows for the identification and characterization of acoustic events, such as those obtained in passive acoustic monitoring applications. Situations where it is difficult to achieve the desired frequency resolution to distinguish between similar events occur, for example, in short time oscillating events. One feasible approach to make discrimination among such events is by measuring the complexity or the presence of non-linearities in a time series. Available techniques include the delay vector variance (DVV) and recurrence plot (RP) analysis, which have been used independently for statistical testing, however, the similarities between these two techniques have so far been overlooked. This work suggests a method that combines the DVV method with the recurrence quantification analysis parameters of the RP graphs for the characterization of short oscillating events. In order to establish the confidence intervals, a variant of the pseudo-periodic surrogate algorithm is proposed. This allows one to eliminate the fine details that may indicate the presence of non-linear dynamics, without having to add a large amount of noise, while preserving more efficiently the phase-space shape. The algorithm is verified on both synthetic and real world time series.

Ultrasonic characterization of GRC with high percentage of fly ash substitution

New applications of non-destructive techniques (NDT) with ultrasonic tests (attenuation and velocity by means of ultrasonic frequency sweeps) have been developed for the characterization of fibre-reinforced cementitious composites. According to new lines of research on glass-fibre reinforced cement (GRC) matrix modification, two similar GRC composites with high percentages of fly ash and different water/binder ratios will be studied. Conventional techniques have been used to confirm their low Ca(OH)(2) content (thermogravimetry), fibre integrity (Scanning Electron Microscopy), low porosity (Mercury Intrusion Porosimetry) and good mechanical properties (compression and four points bending test). Ultrasound frequency sweeps allowed the estimation of the attenuation and pulse velocity as functions of frequency. This ultrasonic characterization was correlated successfully with conventional techniques.

Does breathing type influence electromyographic activity of obligatory and accessory respiratory muscles?

Craniomandibular electromyographic (EMG) studies frequently include several parameters, e.g. resting, chewing and tooth-clenching. EMG activity during these parameters has been recorded in the elevator muscles, but little is known about the respiratory muscles. The aim of this study was to compare EMG activity in obligatory and accessory respiratory muscles between subjects with different breathing types. Forty male subjects were classified according to their breathing type into two groups of 20 each: costo-diaphragmatic breathing type and upper costal breathing type. Bipolar surface electrodes were placed on the sternocleidomastoid, diaphragm, external intercostal and latissimus dorsi muscles. EMG activity was recorded during the following tasks: (i) normal quiet breathing, (ii) maximal voluntary clenching in intercuspal position, (iii) natural rate chewing until swallowing threshold, (iv) short-time chewing. Diaphragm EMG activity was significantly higher in the upper costal breathing type than in the costo-diaphragmatic breathing type in all tasks (P < 0·05). External intercostal EMG activity was significantly higher in the upper costal breathing type than in the costo-diaphragmatic breathing type in tasks 3 and 4 (P < 0·05). Sternocleidomastoid and latissimus dorsi EMG activity did not show significant differences between breathing types in the tasks studied (P > 0·05). The significantly higher EMG activity observed in subjects with upper costal breathing than in the costo-diaphragmatic breathing type suggests that there could be differences in motor unit recruitment strategies depending on the breathing type. This may be an expression of the adaptive capability of muscle chains in subjects who clinically have a different thoraco-abdominal expansion during inspiration at rest.

Fetal cortisol response to intrauterine microbial colonisation identified by the polymerase chain reaction and fetal inflammation

OBJECTIVE

To determine the fetal cortisol response to intrauterine infection.

STUDY DESIGN

16s ribosomal RNA genes or the urease genes of Ureaplasma spp were identified by the polymerase chain reaction in intrauterine samples. Cord blood cortisol, interleukin 6 (IL6) and IL8 were measured in samples from 31 infants born at <32 weeks gestation.

RESULTS

13 infants (median gestation 30 weeks, birth weight 1350 g) had at least one positive intrauterine sample for microbial genes and 18 infants (31 weeks, 1320 g) did not. The cord blood cortisol concentration was significantly higher in fetuses exposed to intrauterine infection and significantly increased in fetuses/mothers presenting in preterm labour with intact membranes compared with infants delivered by elective prelabour caesarean section (p<0.05). The cord blood cortisol concentration was increased in the mothers with prelabour premature rupture of membranes but this was not significant compared with the caesarean section group. The cord blood cortisol concentration was significantly increased in the presence of chorioamnionitis or funisitis and was moderately correlated with cord blood IL6 (r = 0.64, p<0.01) and IL8 (r = 0.52, p<0.01).

CONCLUSIONS

In this study, cord blood cortisol was increased in the colonised group compared with non-colonised infants. It is unclear if infants born following prelabour premature rupture of the membranes mount an adequate anti-inflammatory response.

Laterotrusive occlusal schemes and their effect on supra- and infrahyoid electromyographic activity

The objective of this study was to determine the effects of canine guidance and group function on supra- and infrahyoid electromyographic (EMG) activity. The sample included 40 healthy subjects, 20 with bilateral canine guidance and 20 with bilateral group function. Surface electrodes were used to record the integrated EMG (IEMG) activity of the left supra- and infrahyoid muscles during (1) grinding from intercuspal position to lateral edge-to-edge contact position (with canine guidance or group function), (2) static clenching in edge-to-edge lateral contact position with canine guidance or group function, and (3) grinding from lateral edge-to-edge contact position (with canine guidance or group function) to intercuspal position. IEMG activity in the suprahyoid or infrahyoid muscles was not significantly different with canine guidance or group function. Supra- and infrahyoid IEMG activity in condition 2 was significantly higher than in condition 3, which was significantly higher than in condition 1. Supra- and infrahyoid IEMG activity was not significantly different with canine guidance and group function. Supra- and infrahyoid IEMG activity during the static recording (clenching) was significantly higher than during the dynamic recordings (grinding). Activity during grinding from the lateral edge-to-edge contact position to the intercuspal position was higher than vice versa.

Breathing type and body position effects on sternocleidomastoid and suprahyoid EMG activity

The objective of this study was to determine the effects of breathing type and body position on sternocleidomastoid and suprahyoid electromyographic (EMG) activity. The sample included 18 subjects with upper costal breathing type (study group) and 15 subjects with costo-diaphragmatic breathing type (control group). All individuals had natural dentition and bilateral molar support. EMG recordings at rest and while swallowing saliva were carried out by placing surface electrodes on the left sternocleidomastoid and left suprahyoid muscles. EMG activity was recorded while standing, seated upright, and in the lateral decubitus position. Upper costal breathing type subjects showed a significantly higher suprahyoid EMG activity at rest than costo-diaphragmatic subjects in all body positions studied (mixed model with unstructured covariance matrix). In the lateral decubitus position, both breathing types showed a significantly higher sternocleidomastoid EMG activity at rest and while swallowing saliva. The suprahyoid muscles demonstrated a significantly higher EMG activity at rest as well as in the lateral decubitus position (mixed model with unstructured covariance matrix). These results are relevant because sternocleidomastoid and suprahyoid muscles play an important role in controlling the head posture and mandible dynamics. The neurophysiological mechanisms involved are discussed.

Prevalence of delirium in a geriatric convalescence hospitalization unit: patient's clinical characteristics and risk precipitating factor analysis

The aim was to evaluate the prevalence of delirium among patients discharged from an acute care hospital and admitted to a geriatric convalescence unit (GCU), and to analyze patient's characteristics and risk precipitating factors. Sixty-eight patients were analyzed during a 2-week period. The confusion assessment method (CAM) was used to detect delirium. The precipitating factors evaluated were: major surgery-intensive care unit(ICU) stay, pulmonary and heart failure, acute infections, metabolic disorders/anemia,psychoactive medications, other drugs, severe pain, changing environmental influences and others. According to CAM, fifteen patients presented delirium (22%), and in 14 of them(93.3 %) the delirium was developed before admission at GCU. The precipitating factors in the studied population were the following: changing environmental influences in 66 patients(97%) (15 with delirium and 51 without delirium); other drugs 56 (82.3 %) (11 vs. 45);others 56 (82.3%) (9 vs. 24); psychoactive medications 50 (73.5%) (12 vs. 38); acute infections 48 (70.5 %) (13 vs. 35); metabolic disorders/anemia 40 (58.8 %) (9 vs. 31); major surgery-ICU stay 28 (41 .1%) (8 vs. 20); severe pain 26 (38.2%) (6 vs. 20); pulmonary and heart failure 22 (32.3%) (5 vs. 17). The univariant analysis showed that, none of the precipitating factors studied was significantly related to delirium. Seventy-two patients (91.1%) had simultaneously >3 precipitating factors. There were 16 patients with >6 precipitating factors, 7 of 15 with delirium and 9 of the 53 without delirium (46.6 % vs 16.9 %) (p < 0.05). The prevalence of delirium has been 22 %. Most of the patients had developed delirium before the admission at GCU. A high proportion of patients had >3 precipitating factors. In the study the presence of > 6 precipitating factors simultaneously has been significantly related to delirium.

Validation of a modified version of the Gijon's social-familial evaluation scale (SFES): the "Barcelona SFES Version", for patients with cognitive impairment

The aim was to validate an abbreviated version of the Gijon's social-familial evaluation scale (SFES) (Barcelona-SFES version), on patients with cognitive impairment. A group of 34 patients with cognitive impairment, admitted to an intermediate-long-term-care facility, were analyzed. Mean age was 80.2 +/- 7.4 years. Gijón's SFES was abbreviated and only the first three item groups corresponding to family conditions, social contacts and assistance from the social network were selected. Barcelona-SFES version had a range score between 3 to 15 points, in which low scores identify older patients who live with their family, have good contacts, and participate in community activities. In contrast, high scores identify older persons who live alone and have poor social support and little participation with community activities. Three social risk categories were established according to the Barcelona-SFES score: low social risk (>/= 7 points), intermediate social risk (8-9 points) and high social points). Validation criteria used in the present study were: predictive value of Barcelona-SFES score of post-discharge destination (home or institution), and patient's (or family's) request for a definitive institutionalization in a nursing home. There were 9 patients with low social risk (26.4 %), 8 with intermediate social risk (23.5 %) and 17 with high social risk (50 %). A significant relationship between Barcelona-SFES scores and post-discharge destination was found. Eighty percent of patients discharged to an institution(nursing and residential homes), they had high social risk SFES scores (>/= 10) Also, a significant correlation was found between the number of patients for which a definitive institutionalization request was performed and the Barcelona-SFES scores. Fifteen (88.2 %) of the 18 patients for whom the request was done, were in the high social risk group. The lowest scores from SFES were predictive of home discharge, while the highest scores were predictive of a definitive institutionalization.

On estimating the center frequency of ultrasonic pulses

In this paper we propose a new technique for estimating the center frequency of the ultrasound pulse from records of backscattering noise. We start by considering that the conventional maximum frequency method can be seen as a filtering (differentiator) of the pulse spectrum magnitude followed by a searching for the zero-crossing value. The new approach replaces the differentiator by a Hilbert transformer. We show in the paper that the proposed method has less variance than the maximum frequency method. In particular, we analyse the performance assuming that the real cepstrum method is used for extracting pulse spectrum magnitude. We give an upper bound for the variance reduction when practical criteria are applied for fitting the cepstrum cut-off frequency. The analytical work is verified by real and simulated data.

PREVIOUS COGNITIVE IMPAIRMENT AND FAILURE TO THRIVE SYNDROME IN PATIENTS WHO DIED IN A GERIATRIC CONVALESCENCE HOSPITALIZATION UNIT

Cognitive impairment and depression are commonly associated with poor outcomes in geriatric patients. Both are part of the "failure to thrive syndrome" (FTS), that is a combined group of symptoms as a result from progressive functional, mental and nutritional impairment status in older patients. This paper was aimed at evaluating the presence of FTS in the patients who died in a geriatric convalescence unit (GCU) (intermediate care facility) and comparing the characteristics of patients with primary FTS (not associated with an evident identifiable disease) and secondary FTS (associated with an evident identifiable disease). Finally, we wanted to analyze if the presence of cognitive impairment before admission was associated with the type of FTS. We analyzed 78 patients retrospectively. The presence of the next three conditions was necessary to define the FTS: (i) Impaired functional status and malnutrition. (ii) Cognitive impairment and/or depression. (iii) Absence of improvement, after a specific geriatric intervention program during the hospitalization. Functional status for basic and instrumental activities of daily living (ADL and IADL) and the presence of symptoms cognitive impairment before admission were evaluated. Of the 78 analyzed patients, there were 30 (38.4%) with symptoms of FTS. Seventeen of them (56.6%) had a secondary FTS and 13 (43.3%) a primary one. This last group of patients had a significantly higher mean age (84.7 +/- 5.8 vs. 78.6 +/- 7.2; p < 0.02) and before admission they were significantly more dependent for ADL: 10 patients (76.9%) vs. 7 (41.0%) chi2 = 3.833, p < 0.05. A higher proportion of subjects with cognitive impairment before admission was found in the group of patients with primary FTS, than in those secondary FTS, although this difference did not reach statistical significance. Patients with primary FTS seem to be older and more dependent for ADL before admission, than those with secondary FTS.

EVALUATION OF FUNCTIONAL IMPROVEMENT IN OLDER PATIENTS WITH COGNITIVE IMPAIRMENT, DEPRESSION AND/OR DELIRIUM ADMITTED TO A GERIATRIC CONVALESCENCE HOSPITALIZATION UNIT

Cognitive impairment, depression and delirium are problems of high prevalence in older patients. The geriatric convalescence unit (GCU) is a hospitalization facility offering an interdisciplinary geriatric intervention program that may be more appropriate for these patients. This study intended to analyze the functional improvement (FI) in older patients with cognitive impairment, depression and/or delirium admitted to a GCU. A group of 107 patients received specific nurse care, habitually performed in GCU and they also were included in a rehabilitation program. Cognitive impairment, depression and delirium were diagnosed according to standardized protocols. The analyzed variables were: age, functional status (Barthel index) before admission (BBA), at admission (BA) and at discharge(BD), diagnostic categories, cognitive function (mini mental state examination: MMSE) and post-discharge destination. The corrected Heinemann index (CHI) was used to evaluate FI obtained during GCU-stay, where CHI = 100 x (BD-BA)/(BBA-BA), and the efficiency index(El) was used to analyze the relationship between FI and the length of stay in the GCU,where El = (BD-BA)/(days in GCU). According to CHI, patients were divided in three groups. Group I: CHI = 0 or negative (patients who lost functional capacity during hospitalization,those who died or were transferred to hospital owing to acute deterioration. Group II: CHI < 35 % (high FI). Mean age was 77.6 +/- 9.1 years, the diagnostic categories were: fractures/orthopedics 49 (45.7 %), neurological 27(25.2 %), pulmonary/cardiologic 6 (5.6 %) and other cases 25 (23.3 %). Mean MMSE and BA scores were 16.9 +/- 9.4 and 29.6 +/- 18.9, respectively. Post-discharge destinations were:63 patients (58.8 %) returned home, 28 (26.1 %) were definitively institutionalized, 11 (10.2%) died and finally 5 (4.6 %) were transferred to acute care hospital. In-Group I, there were 35 patients (32.7 %) with a mean value of the El = 0.12 +/-1.1; in Group II, 13 (12.1 %) and 0.26 +/- 0.38; in Group III, 59 (55.1 %) and 0.94 +/- 0.97, respectively. In spite of the presence of cognitive impairment, depression and/or delirium, a high proportion of patients (67.2 %)obtained a significant improvement in their functional capacity.35 % (moderate FI). Group III: CHI >/=

OBSERVATIONAL SCALE AND GERIATRIC DEPRESSION SCALE OF YESAVAGE TO IDENTIFY DEPRESSIVE SYMPTOMS IN OLDER PATIENTS

The diagnosis of depression by clinical interview may be difficult in the patients with communication problems (aphasia, severe cognitive impairment or severe deafness). In these cases, depressive symptoms may be observed by others (nurses and caregivers). The aim of this study was to evaluate the clinical usefulness of an observational scale to identify depression in older patients. Seventy-six institutionalized patients in an intermediate-long-term care center were evaluated. Of them, 39 were excluded because they were unable to perform a clinical interview, needed to diagnose depression. Of the excluded patients, 18 had aphasia, 7 showed severe cognitive impairment: their mini mental state examination (MMSE) score < 14, and 14 collaborated very poorly. Thus 37 patients were analyzed, mean age was 83 +/- 0.86 years (30 women and 7 men). Diagnostic categories were: neurological 16 patients (43.2%), fractures/orthopedics 6 (16.2%), pulmonary/cardiology 5 (13.5%) and others 10 (27.1%). The mean Barthel index was 57.0 +/- 31.6 and mean MMSE score was 21.1 +/- 4.3. The observational scale (OS) designed with six items, was applied to all patients. Each item was scored as never (0 points), sometimes (1 point) and always (2 points). Thus total OS score ranged from 0 to 12. Two observers, who knew the patients (nurses), applied the OS. A trained geriatrician, using the 15-item geriatric depression scale (GDS) performed detection of depressive symptoms. There were 15 patients (40.5 %) with depression on the GDS. OS scale score with a cutoff point of 5 or more was present in 13 patients; nine of them had depression (69.2 %). In the remaining 24 patients with an OS score < 5, depression was present only in 6 cases (25%) (chi2 = 6.844; p < 0.01). The OS >/= 5, in the present study, obtained a sensitivity of 60 %, a specificity of 81 %, a positive predictive value of 69 %, and a negative predictive value of 75 %.We concluded that (i) the OS has been useful for identifying depressive symptoms with an acceptable sensitivity and specificity, and (ii) the OS may be an alternative to detect depression in patients who are unable to perform a clinical interview.

CLINICAL IMPACT OF DIFFERENT SCORES OF THE MINI NUTRITIONAL ASSESSMENT (MNA) IN THE DIAGNOSIS OF MALNUTRITION IN PATIENTS WITH COGNITIVE IMPAIRMENT

It was aimed at evaluating the clinical usefulness of the mini nutritional assessment (MNA) to identify malnutrition in elderly patients with cognitive impairment, admitted to a geriatric convalescence unit (intermediate care facility). Sixty-three patients with cognitive impairment were studied. Cognitive impairment was considered when mini mental state examination (MMSE) scores were below 21. MNA and a nutritional evaluation according to the sequential model of the American Institute of Nutrition (AIN) were performed at admission. According to the AIN criteria, malnutrition was considered, if there were abnormalities in at least one of the following parameters: albumin, cholesterol, body mass index (BMI), and branchial circumference. Based on these criteria, 27 patients (42.8%) proved to be undernourished at admission, whereas if taking the original MNA scores, 39 patients (61.9%) were undernourished, 23 (36.5%) were at risk of malnutrition, and 1 (1.5%) was normal. The analyzed population was divided in four categories (quartiles) of the MNA scores: very low (</= 13.5), low (> 13.5 and </= 16), intermediate (> 16 and </= 18.5) and high (> 18.5). Likelihood ratios of each MNA quartile were obtained by dividing the percentage of patients in a given MNA category who were undernourished (according to AIN) by the percentage of patients in the same MNA category who were not undernourished. In the very low MNA quartile, this likelihood ratio was 2.79 and for the low MNA quartile it was 0.49. For intermediate and high MNA categories, likelihood ratios were 1.0 and 0.07 respectively. In the present study, MNA identified undernourished patients with a high clinical diagnostic impact value only, when very low scores (</= 13) are obtained.

Vertical dimension. Part 1: comparison of clinical freeway space

This study was conducted in order to compare the clinical freeway space measurements using three simple methods commonly used by dentists in their practices. The study was performed in 15 young healthy subjects with natural dentition and bilateral molar support. Artificial landmarks (adhesive tape) were placed on the more prominent parts of the nose and chin of each subject. Vertical dimension of occlusion (VDO) was measured in the intercuspal position. Postural vertical dimension (PVD) was measured in the following functional conditions: after swallowing saliva, after pronouncing the word "Mississippi", and in a relaxed postural mandibular position (RPMP). Then, the clinical freeway space value in each functional condition was obtained by subtracting VDO from PVD value. Significant differences among clinical freeway space values using three different methods were observed (ANOVA). A significantly higher clinical freeway space value was found using phonetics method than after swallowing and with the mandible in a relaxed postural position (Bonferroni multiple comparison test). No significant differences between swallowing and relaxed methods were found. These results seem to suggest that the measures of clinical freeway space depend upon the method used.

[Effectiveness and cost of total hip replacement in seven hospitals in Catalonia, Spain]

BACKGROUND

To quantify short-term benefits of total hip replacement, prognostic factors of the outcome, and to assess hospital costs of this surgical procedure in Catalonia, Spain.

PATIENTS AND METHODS

Multicentric prospective study in seven hospitals in Catalonia. All patients undergoing this procedure in one year were included. They were evaluated prior to the operation, and six months later. This evaluation involved: clinical assessment, the Hip Pain and Function Scale, the Nottingham Health Profile (NHP), and the EuroQol (EQ-5D), in order to measure cost-utility. Hospital costs were estimated by means of a specific questionnaire.

RESULTS

Information was obtained for 332 patients. The mean age was 65 years (range: 27-89 years); 58% were women; the most common diagnosis was arthritis; 59% of patients had associated pathology and 13% presented some type of postoperative complication. The improvement in health status was important according to all instruments. An outcome of "excellent" or "good" was achieved by 70.8% of the patients, in terms of hip function and pain. The factors associated with not achieving an outcome of this level were: associated pathology, complications, diagnoses other than arthritis, and operation carried out in a tertiary hospital. The total cost of the procedure was 838,480 pesetas. This average varied significantly with the cost of the prosthesis, and as a function of the length of stay. The three-year cost-utility of the procedure was estimated as 507,500 pesetas.

CONCLUSIONS

Total hip replacement greatly improves the pain, hip function and overall perceived health of the patient. This improvement is greater among patients with a diagnosis of arthritis, with good overall health, operated on by a surgeon experienced in this procedure. The benefit is high in relation to the cost, although there is a margin for improvement, reducing complications, shortening length of stay, and controlling the price of implants.

Effects of head and neck inclination on bilateral sternocleidomastoid EMG activity in healthy subjects and in patients with myogenic cranio-cervical-mandibular dysfunction

This study was conducted in order to determine the effect of head and neck position on bilateral electromyographic (EMG) activity of the sternocleidomastoid muscles. The study was performed on 16 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 16 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the right and left sternocleidomastoid muscles. EMG activity was recorded in the left lateral decubitus position, in a darkened room and with the individual's eyes closed, under the following experimental conditions: 1. Head, neck, and body horizontally aligned; 2. Head and neck upwardly inclined with respect to the body, simulating the effect of a thick pillow, 3. Head and neck downwardly inclined with respect to the body, simulating the effect of a thin pillow. Variation of head and neck positions was determined by measuring the distance from the angle of neck and shoulder and the apex of the shoulder (SND = shoulder-neck distance) of each individual. Then, head and neck were forward or downwardly inclined with respect to the body at one-third of SND. A significantly higher contralateral EMG activity and a more asymmetric EMG activity were observed in the CMD group than in the healthy subjects (Kruskal-Wallis Test). These results suggest a different behavior of bilateral sternocleidomastoid EMG activity in CMD patients than in healthy subjects depending on the positioning of the head and neck.

The evolution of RNA viruses: A population genetics view

RNA viruses are excellent experimental models for studying evolution under the theoretical framework of population genetics. For a proper justification of this thesis we have introduced some properties of RNA viruses that are relevant for studying evolution. On the other hand, population genetics is a reductionistic theory of evolution. It does not consider or make simplistic assumptions on the transformation laws within and between genotypic and phenotypic spaces. However, such laws are minimized in the case of RNA viruses because the phenotypic space maps onto the genotypic space in a much more linear way than on higher DNA-based organisms. Under experimental conditions, we have tested the role of deleterious and beneficial mutations in the degree of adaptation of vesicular stomatitis virus (VSV), a nonsegmented virus of negative strand. We also have studied how effective population size, initial genetic variability in populations, and environmental heterogeneity shapes the impact of mutations in the evolution of vesicular stomatitis virus. Finally, in an integrative attempt, we discuss pros and cons of the quasispecies theory compared with classic population genetics models for haploid organisms to explain the evolution of RNA viruses.

Comparative study between children with and without cleft lip and cleft palate, part 1: cephalometric analysis

OBJECTIVE

This study was conducted to compare craniofacial relationships, position, and curvature of the cervical spine between children with cleft lip and cleft palate who had been operated on and children without clefts.

METHOD

This study was performed in 28 children with mixed dentition. They were divided into two groups. The study group included 14 children with unilateral operated cleft lip and cleft palate, ranging in age from 6 to 12 years, who clinically presented with a short upper lip, abnormal lip seal, and inhibition of sagittal development of the midface that was radiographically assessed. The control group included 14 children without clefts, ranging in age from 8 to 11 years. All of them had normal lip seal, nasal breathing, and a clinically normal body posture.

DESIGN

A lateral craniocervical radiograph in a self-balanced natural head position in an erect posture, and without using a head holder, was taken for each child of both groups, with the mandible in maximum intercuspation and lips in habitual posture. The true vertical was marked on all the films. Specific angular and linear dimensions were used to assess the craniocervical relationships, as were the position of the cervical spine, its curvature, or both.

RESULTS AND CONCLUSIONS

The study group presented a significant increase in the extension of the head on the neck, forward position of the cervical spine, and a decrease in the curvature of the cervical spine in comparison with the children without clefts. These results are more relevant considering that the study group also presented higher significant values of lower facial height than children without clefts.

Comparative study between children with and without cleft lip and cleft palate, part 2: electromyographic analysis

OBJECTIVE

This study was conducted to compare electromyographic (EMG) activity of superior orbicularis oris muscle between children with repaired cleft lip and cleft palate and children without clefts.

METHODS

This study included 28 children with mixed dentition. They were divided into two groups. The study group included 14 children with repaired unilateral cleft lip and cleft palate, ranging in age from 6 to 12 years, who presented clinically with a short upper lip, abnormal lip seal, and inhibition of sagittal development of the midface as assessed radiographically. The control group included 14 children without clefts ranging in age from 8 to 11 years. All had normal lip seal, nasal breathing, and a clinically normal body posture.

DESIGN

Bipolar surface electrodes were used for EMG recordings of resting level activity and during swallowing of saliva, speech, and chewing and swallowing of an apple.

RESULTS AND CONCLUSIONS

A significantly higher level of activity at rest and during swallowing of saliva was observed in the cleft lip and cleft palate group. Similar activity during speech and chewing and swallowing of an apple was observed in both groups. The higher level of activity at rest and during swallowing of saliva in children with cleft lip and cleft palate seems to suggest that upon higher functional demands their activity increases less than in children without clefts. From a clinical point of view, if increased EMG activity at rest and during swallowing of saliva reflects increased force on the maxilla, then our findings may corroborate Bardach's findings (1990) that surgical treatment of cleft lip has an iatrogenic effect on facial growth, although the lack of significant correlation between the cephalometric data and EMG findings in the present study.

Diminishing returns of population size in the rate of RNA virus adaptation

Whenever an asexual viral population evolves by adapting to new environmental conditions, beneficial mutations, the ultimate cause of adaptation, are randomly produced and then fixed in the population. The larger the population size and the higher the mutation rate, the more beneficial mutations can be produced per unit time. With the usually high mutation rate of RNA viruses and in a large enough population, several beneficial mutations could arise at the same time but in different genetic backgrounds, and if the virus is asexual, they will never be brought together through recombination. Thus, the best of these genotypes must outcompete each other on their way to fixation. This competition among beneficial mutations has the effect of slowing the overall rate of adaptation. This phenomenon is known as clonal interference. Clonal interference predicts a speed limit for adaptation as the population size increases. In the present report, by varying the size of evolving vesicular stomatitis virus populations, we found evidence clearly demonstrating this speed limit and thus indicating that clonal interference might be an important factor modulating the rate of adaptation to an in vitro cell system. Several evolutionary and epidemiological implications of the clonal interference model applied to RNA viruses are discussed.

The two faces of mutation: extinction and adaptation in RNA viruses

From a population standpoint, two main features characterize the replication of RNA viruses and viruses that use RNA as a replicative intermediate: high genetic variability, and enormous fluctuations in population size. Their genetic variability mainly reflects a lack of the proof-reading and post-replicative error correction mechanisms that operate during cellular DNA replication, but recombination and segment exchange can also play an important role. Viral population size can change tremendously as a consequence of transmission between hosts or between different tissues within an infected host. A new infection can be initiated with very few particles that subsequently expand many trillion-fold. Repeated bottleneck events can lead to drastic fitness losses or even to viral extinction, whereas continuously large population sizes result in fitness gains and adaptation. Here we review experimental evidence for the effects of mutation, selection, and genetic drift on the adaptation and extinction of RNA viruses.

The two faces of mutation: extinction and adaptation in RNA viruses

From a population standpoint, two main features characterize the replication of RNA viruses and viruses that use RNA as a replicative intermediate: high genetic variability, and enormous fluctuations in population size. Their genetic variability mainly reflects a lack of the proof-reading and post-replicative error correction mechanisms that operate during cellular DNA replication, but recombination and segment exchange can also play an important role. Viral population size can change tremendously as a consequence of transmission between hosts or between different tissues within an infected host. A new infection can be initiated with very few particles that subsequently expand many trillion-fold. Repeated bottleneck events can lead to drastic fitness losses or even to viral extinction, whereas continuously large population sizes result in fitness gains and adaptation. Here we review experimental evidence for the effects of mutation, selection, and genetic drift on the adaptation and extinction of RNA viruses.

Clonal interference and the evolution of RNA viruses

In asexual populations, beneficial mutations that occur in different lineages compete with one another. This phenomenon, known as clonal interference, ensures that those beneficial mutations that do achieve fixation are of large effect. Clonal interference also increases the time between fixations, thereby slowing the adaptation of asexual populations. The effects of clonal interference were measured in the asexual RNA virus vesicular stomatitis virus; rates and average effects of beneficial mutations were quantified.

[Factors predicting return home of hospitalized aged patients]

BACKGROUND

The identification of predictors of return home and nursing home placement in elderly patients, at the moment of admission to a Geriatric Convalescence Unit, may allow to make a discharge planning for these patients, and also may improve efficiency in the unit.

PATIENTS AND METHODS

A number of 445 patients over 65 years were consecutively admitted to the unit. Analyzed variables at admission were; age, sex, diagnostic, comorbidity, functional status prior to admission, degree of independence in activities of daily living (Barthel index), cognitive function (Folstein Mini-Mental) and social support (modified version of social-familiar evaluation scale of Gijón). All these variables were used in two models of logistic regression analysis: 1 [symbol: see text] (dependent variable: return home after discharge versus other destinations), and 2 [symbol: see text] (dependent variable: nursing home placement on discharge versus other destinations).

RESULTS

The variables significatively associated with greater probability of at home discharge were: moderate dependency for activities of daily living (Barthel index = 31-59), odds ratio (OR) = 2.46 (95% confidence interval: 1.43-4.22); mild dependency (Barthel index > or = 60), OR = 3.67 (1.96-6.87); normal cognitive function (Mini-Mental > or = 21), OR = 3.14 (1.76-5.60), and a favourable social support (social-familiar scale < 12), OR = 7.33 (3.18-16.91). The only variable significatively associated with the probability of nursing home placement after discharge was an impaired social function (social-familiar scale > or = 12), OR = 4.53 (2.25-9.12).

CONCLUSIONS

Probability of return home after discharge is associated with functional status, cognitive function and social support. Definitively nursing home placement was only related with de degree of familiar support.

Effects of two types of pillows on bilateral sternocleidomastoid EMG activity in healthy subjects and in patients with myogenic cranio-cervical-mandibular dysfunction

This study was conducted in order to determine the effects of two types of pillows on bilateral electromyographic (EMG) activity of the sternocleidomastoid muscles. The study was performed on 15 patients with myogenic cranio-cervical mandibular dysfunction (CMD) and 15 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the right and left sternocleidomastoid muscles. EMG activity was recorded in the supine position and in the lateral decubitus position (according to each individual's normal resting habit), with their eyes closed and with the head supported by means of: 1. a Sleep Easy Pillow (Interwood Marketing Groups, Concord, Ontario, Canada) and 2. a Standard Pillow (INDUVET). In the lateral decubitus position a significantly higher contralateral than ipsilateral EMG activity at rest in the sternocleidomastoid muscles was observed with both types of pillows in all the sample studied (ANOVA and Duncan's Multiple-Range Test). Asymmetrical bilateral EMG activity in the lateral decubitus position with both types of pillows in healthy subjects and in patients with myogenic CMD, suggests that if this body posture is prolonged, it could be important in the genesis of sternocleidomastoid hyperactivity.

Body position effects on EMG activity of the temporal and suprahyoid muscles in healthy subjects and in patients with myogenic cranio-cervical-mandibular dysfunction

This study was conducted in order to determine the effects of body position on integrated electromyographic (IEMG) activity of anterior temporal and suprahyoid muscles. The study was performed on 15 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 15 healthy subjects. IEMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the anterior temporal and suprahyoid muscles in the following body positions: standing, seated, supine, and lateral decubitus position. Insignificant changes in IEMG activity of both muscles were observed upon variations in the body position. Insignificant differences in IEMG activity were observed between patients with myogenic CMD and healthy subjects. A pattern of higher IEMG at rest and during swallowing of saliva was observed in the suprahyoid muscles than in the anterior temporal muscles, whereas during maximal clenching activity, an opposite pattern was observed. Results of the present study seem to suggest that for the anterior temporal and suprahyoid muscles there is no specific body position that could be relevant to initiate and/or to perpetuate a craniomandibular dysfunction.

Visual input effect on EMG activity of sternocleidomastoid and masseter muscles in healthy subjects and in patients with myogenic cranio-cervical-mandibular dysfunction

This study was conducted in order to determine the input visual effect on electromyographic (EMG) activity of the sternocleidomastoid and masseter muscles in the supine and lateral decubitus positions. The study was performed on 22 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 18 healthy subjects. EMG activity at rest and during swallowing of saliva and maximal voluntary clenching was recorded in the supine and lateral decubitus positions in the following conditions: 1. with eyes open; and 2. with eyes closed after 5 minutes in a dark room. A significant decrease of EMG activity at rest with closed eyes in both groups was observed in the sternocleidomastoid (lateral decubitus position) and in the masseter muscle (supine position). During swallowing of saliva a significant decrease of EMG activity with closed eyes was observed only in the sternocleidomastoid muscle (lateral decubitus position) in healthy subjects. During maximal voluntary clenching any significant differences were observed upon variation in the visual input. The significant change in EMG activity, mainly observed at rest, suggests that the visual input effect is weak. The absence of a significant change in EMG activity during maximal voluntary clenching upon variation in the visual input could be clinically relevant in patients with myogenic CMD who habitually brux.

Body position effects on EMG activity of sternocleidomastoid and masseter muscles in healthy subjects

This study was conducted in order to determine the effects of body position on integrated electromyographic (IEMG) activity of sternocleidomastoid and masseter muscles in 20 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the sternocleidomastoid and masseter muscles (contralateral to the habitual side of sleeping of each subject), in the following body positions: standing, seated, supine, and lateral decubitus position. Significant higher EMG activities were recorded in the sternocleidomastoid muscle in the lateral decubitus position, whereas significant lower EMG activities were recorded in the masseter muscle in the supine position. This finding supports the idea that there may exist a differential modulation of the motor neuron pools of the sternocleidomastoid and masseter muscles of peripheral and/or central origin. Significant differences in the EMG pattern as well as in the levels of EMG activities upon variations in body positions were observed between healthy subjects and patients with myogenic craniomandibular dysfunction reported by Palazzi, et al.

Body position effects on sternocleidomastoid and masseter EMG pattern activity in patients undergoing occlusal splint therapy

This study was conducted in order to determine the effects of body position on electromyographic (EMG) activity of sternocleidomastoid and masseter muscles, in 15 patients with myogenic cranio-cervical-mandibular dysfunction undergoing occlusal splint therapy. EMG activity was recorded by placing surface electrodes on the sternocleidomastoid and masseter muscles (contralateral to the habitual sleeping side of each patient). EMG activity at rest and during swallowing of saliva and maximal voluntary clenching was recorded in the following body positions: standing, supine and lateral decubitus. In the sternocleidomastoid muscle significant higher EMG activities at rest and during swallowing were recorded in the lateral decubitus position, whereas during maximal voluntary clenching EMG activity did not change. In the masseter muscle significant higher EMG activity during maximal voluntary clenching in a standing position was observed, whereas EMG activity at rest and during swallowing did not change. The opposite pattern of EMG activity supports the idea that there may exist a differential modulation of the motor neuron pools of the sternocleidomastoid and masseter muscles, of peripheral and/or central origin. This suggests that the presence of parafunctional habits and body position could be closely correlated with the clinical symptomatology in these muscles in patients with myogenic craniomandibular dysfunction.

Increase of the vertical occlusal dimension by means of a removable orthodontic appliance and its effect on craniocervical relationships and position of the cervical spine in children

The aim of this study was to determine the effect of the increase in the occlusal vertical dimension by means of an orthodontic appliance on craniocervical relationships and position of the cervical spine. Thirty children presenting malocclusion were divided into two groups of 15 (a study and a control group). Those in the study group wore an orthodontic appliance to correct cross-bite. The children in the control group had no treatment during the experimental period. Two lateral craniocervical radiographs were taken for each child. The first one was taken in the intercuspal position in both groups. The second radiograph was taken of the study group after four months of wearing the appliance and also of the control group after four months. Cephalometric analysis in the study group showed a significant forward cervical spine position. There were no significant changes in the control group. The changes found in the study group suggest that when there are signs and symptoms of cervical dysfunction in children undergoing long-term orthodontic treatment, it is necessary to make an evaluation of the cervical column position after the insertion of any orthodontic appliance which increases the occlusal vertical dimension.

Is group selection a factor modulating the virulence of RNA viruses?

RNA viruses consist of populations of extremely high genetic heterogeneity called quasispecies. Based on theoretical considerations, it has been suggested that the unit of selection in such complex genetic populations is not the single viral particle but a set of genetically related particles which form the quasispecies. In the present study we carried out a set of experiments with the vesicular stomatitis virus (VSV) dealing with the evolution of life-history characters under selection acting at two factors either in the same or in opposite directions. The two factors at which selective pressure is applied are the individual and the group. We show evidence that group selection modulates the virulence of VSV populations, in opposition to an unlimited increase in virulence by competitive optimization promoted by individual selection. The results are of relevance for understanding the evolution of parasite virulence.

Autonomic dysfunction in patients with non-alcoholic chronic liver disease

AIMS

To assess the presence of autonomic neuropathy in patients with non-alcoholic chronic liver disease and its relationships with the severity of liver damage.

METHODS

Thirty non-alcoholic patients with chronic liver disease and 26 healthy control subjects were studied. The silicone imprint technique was used to quantify the number of functioning sweat glands in order to assess peripheral sympathetic dysfunction. Heart rate variations in response to deep breathing at 6 per minute (deltaR6), to a Valsalva maneuver, and with orthostatism (RRmax/RRmin) were determined to assess parasympathetic vagal function.

RESULTS

Mean values for autonomic tests were significantly lower in the group of patients with non-alcoholic chronic liver disease than in the control subjects. The number of activated sweat glands in the foot was abnormal in 19 (63%) patients. Among vagal tests, Valsalva ratio was abnormal in 14 (46%) and deltaR6 in 11 (36%) patients with liver disease. Vagal neuropathy (two or more abnormal heart rate tests) was definite in nine patients (30%).

CONCLUSIONS

A high prevalence of abnormalities in both sympathetic and parasympathetic function tests, with a poor relationship with liver function parameters, has been found in patients with non-alcoholic chronic liver disease.

Body position effects on EMG activity of sternocleidomastoid and masseter muscles in patients with myogenic cranio-cervical-mandibular dysfunction

This study was conducted in order to determine the effects of body position on integrated electromyographic (IEMG) activity of sternocleidomastoid and masseter muscles in 17 patients with myogenic cranio-cervical-mandibular dysfunction. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the sternocleidomastoid and masseter muscles (contralateral to the habitual side of sleeping of each patient), in the following body positions: standing, seated, supine, and lateral decubitus position. Significant higher EMG activities were recorded in the sternocleidomastoid muscle in the lateral decubitus position and in the supine position (except during swallowing), whereas a significant higher EMG activity was recorded in the masseter muscle during maximal voluntary clenching in standing and seated positions. The EMG pattern observed suggests that the presence of parafunctional habits and body position could be closely correlated with the clinical symptomatology in the sternocleidomastoid and masseter muscles at wakening and during waking hours, respectively, in patients with myogenic cranio-cervical-mandibular dysfunction.