Every fifth child and adolescent in Finland is overweight

Background

Globally, the prevalence of child and adolescent overweight and obesity has increased during the preceding decades leading to childhood obesity being acknowledged as one of the most significant health hazards of the 21st century. Yet, in Finland comprehensive and up-to-date data on the prevalence of overweight and obesity among children and adolescents have been lacking. The aim of this study was to examine the prevalence of overweight and obesity among 2-16-year-old children and adolescents living in Finland in 2018.

Methods

The study was based on height and weight measurements taken at child welfare clinics and school health services between 5.7.2017 and 5.4.2019 (n = 375,561). The data was collected from the Register of Primary Health Care Visits. Child and adolescent overweight and obesity were defined according to international IOTF BMI criteria (age- and sex-specific BMI cut-off points corresponding to adults' cut-off points of 25 kg/m2 for overweight and 30 kg/m2 for obesity) and reported by age group and sex.

Results

In 2018, nearly 20% of boys and girls aged 2-16 years were classified as at least overweight while the prevalence of obesity was 5% among both sexes. The prevalence of overweight in pre-school-aged children (2-6 years) was 12% in boys and 15% in girls, in primary school-aged children (7-12 years) 23% in boys and 22% in girls and in adolescents (13-16 years) 25% in boys and 23% in girls.

Conclusions

In 2018, every fifth child and adolescent in Finland was classified as either overweight or obese. The prevalence of overweight and obesity appears to increase with age in both genders.

Key messages

Childhood and adolescent overweight and obesity were comparatively common in Finland in 2018. As overweight and obesity often persist into adulthood, multi-professional interventions targeted at prevention and early detection are essential.

FinChildren Register: National monitoring of child and adolescent health and well-being in Finland

Background

Comprehensive and up-to-date data on child and adolescent health and well-being is essential for monitoring, service development and decision-making. Although nearly all children and adolescents in Finland attend annual health check-ups at child health clinics and school healthcare, the utilization of collected data has been limited. The objective is to produce timely and representative information on the health and well-being of children, adolescents and their families based on routinely collected register data.

Methods

Data are collected from health check-ups performed at child health clinics and school health care. Recorded data are transferred through patient information systems to the Register of Primary Health Care Visits. The data can be linked to other national registers with personal identity codes. The first phase aimed to evaluate the availability and quality of register-based data through inspection of data coverage on height and weight data of children and adolescents aged 2 to 16 years.

Results

In 2018, the coverage of height and weight data ranged from 0% to 100% between municipalities depending on age group. Results were published through an interactive map application and municipality-specific summaries by gender and age group at national and municipality levels. The data enabled reporting up-to-date results on the prevalence of child and adolescent overweight and obesity in Finland.

Conclusions

Data from health check-ups form an excellent database for monitoring child and adolescent health and well-being in Finland. The challenges of utilizing register data are mainly caused by difficulties in data transfer from patient information systems resulting in insufficient data coverage. Publishing local-level reports on data coverage as well as on the results promotes data availability and quality while enabling evaluation of actions needed for promoting the health and welfare of children and their families.

Neonatal brainstem auditory function associates with early receptive language development in preterm children

AIM

To study whether auditory function measured with brainstem auditory evoked potential and brainstem audiometry recordings in the neonatal period associates with language development 1 year later in preterm infants.

METHODS

This retrospective study included 155 preterm infants (birthweight ≤1500 g and/or birth ≤32 gestational weeks) born between 2007 and 2012 at the Turku University Hospital. Auditory function was recorded in neonatal period. Information of language development was gathered at the mean corrected age of 1 year by using the Finnish version of the MacArthur Communicative Development Inventory.

RESULTS

Slower auditory processing (longer interpeak interval, IPI I-V) in the right ear in the neonatal brainstem auditory evoked potential recording associated with smaller receptive lexicon size at 1 year (P = .043). Infants with longer IPI I-V were more likely to have a deviant (≤17 words) receptive lexicon size (P = .033). The absence of a contralateral response with right ear stimulation increased the risk for deviant lexicon size (P = .049).

CONCLUSION

The results suggest that impaired auditory function in the neonatal period in preterm infants may lead to a poorer receptive language outcome 1 year later. Auditory pathway function assessment provides information for the identification of preterm children at risk for weak language development.

The analgesic effect of therapeutic rTMS is not mediated or predicted by comorbid psychiatric or sleep disorders

BACKGROUND

Mechanisms underlying alleviation of neuropathic pain by repetitive transcranial magnetic stimulation (rTMS) of primary motor cortex (M1) and right secondary somatosensory cortex (S2) are only partly known. Patients with chronic neuropathic pain often have comorbidities like depression and sleep problems. Through functional connectivity, rTMS of M1 and S2 may activate dorsolateral prefrontal cortex, the target for treating depression with rTMS. Thus, the analgesic effect of rTMS could be mediated indirectly via improvement of psychiatric comorbidities or sleep. We examined whether rTMS has an independent analgesic effect or whether its clinical benefits depend on effects on mood or sleep. We also evaluated if comorbid psychiatric or sleep disorders predict the treatment outcome.

METHODS

Sixteen patients with chronic drug-resistant neuropathic orofacial pain participated in this randomized controlled crossover rTMS study. Patients' psychiatric history was evaluated by a specialist in psychiatry. Intensity and interference of pain, mood, and the quality of sleep and life were evaluated at baseline and after 2 active (primary somatosensory cortex [S1]/M1 and S2) and placebo rTMS treatments. A logistic regression analysis was done to investigate predictors of treatment outcome.

RESULTS

The analgesic effect of the right S2 stimulation was not associated with improvement of psychiatric conditions or sleep, whereas S1/M1 stimulation improved sleep without significant analgesic effect (P = 0.013-0.046 in sleep scores). Psychiatric and sleep disorders were more common in patients than in the general population (P = 0.000-0.001 in sleep scores), but these comorbidities did not predict the rTMS treatment outcome.

CONCLUSION

We conclude that rTMS to the right S2 does not exert its beneficial analgesic effects in chronic neuropathic orofacial pain via indirect improvement of comorbid psychiatric or sleep disorders.

Right secondary somatosensory cortex-a promising novel target for the treatment of drug-resistant neuropathic orofacial pain with repetitive transcranial magnetic stimulation

High-frequency repetitive transcranial magnetic stimulation (rTMS) of the motor cortex has analgesic effect; however, the efficacy of other cortical targets and the mode of action remain unclear. We examined the effects of rTMS in neuropathic orofacial pain, and compared 2 cortical targets against placebo. Furthermore, as dopaminergic mechanisms modulate pain responses, we assessed the influence of the functional DRD2 gene polymorphism (957C>T) and the catechol-O-methyltransferase (COMT) Val158Met polymorphism on the analgesic effect of rTMS. Sixteen patients with chronic drug-resistant neuropathic orofacial pain participated in this randomized, placebo-controlled, crossover study. Navigated high-frequency rTMS was given to the sensorimotor (S1/M1) and the right secondary somatosensory (S2) cortices. All subjects were genotyped for the DRD2 957C>T and COMT Val158Met polymorphisms. Pain, mood, and quality of life were monitored throughout the study. The numerical rating scale pain scores were significantly lower after the S2 stimulation than after the S1/M1 (P = 0.0071) or the sham (P = 0.0187) stimulations. The Brief Pain Inventory scores were also lower 3 to 5 days after the S2 stimulation than those at pretreatment baseline (P = 0.0127 for the intensity of pain and P = 0.0074 for the interference of pain) or after the S1/M1 (P = 0.001 and P = 0.0001) and sham (P = 0.0491 and P = 0.0359) stimulations. No correlations were found between the genetic polymorphisms and the analgesic effect in the present small clinical sample. The right S2 cortex is a promising new target for the treatment of neuropathic orofacial pain with high-frequency rTMS.

Halogen bonds with coordinative nature: halogen bonding in a S–I+–S iodonium complex

A thorough characterization of unusually strong I⁺–S halogen bonds indicates that halogen bonding is not merely an electrostatic contact but also has a strong coordinative nature, thus expanding the scope of halogen bonding.

Modification of the supramolecular structure of [(thione)IY] (Y = Cl, Br) systems by cooperation of strong halogen bonds and hydrogen bonds

Strong halogen bonds and hydrogen bonds cooperated to control the supramolecular structures of [(thione)IY] (Y = Cl, Br) compounds.

Progressive external ophthalmoplegia in southwestern Finland: a clinical and genetic study

BACKGROUND

Progressive external ophthalmoplegia (PEO) is a common phenotype of mitochondrial disease. Molecular etiologies include sporadic, large-scale deletions in mitochondrial DNA (mtDNA), multiple mtDNA deletions secondary to autosomal dominant or recessive mutations and mtDNA point mutations.

METHODS

We studied the prevalence and clinical and genetic characteristics of PEO in a defined population in southwestern Finland. A total of 620 patients were first identified from the patient registry at the Turku University Hospital over an 18-year period. The medical records of these patients were scrutinized, and those with clinical features compatible with PEO were ascertained.

RESULTS

We identified 10 patients with possible PEO. The patients were examined clinically, and DNA was analyzed for mtDNA deletions and for the m.3243A>G and m.8344A>G mtDNA point mutations. The ANT1, PEO1, POLG1 and POLG2 genes were sequenced. We confirmed the clinical diagnosis of PEO in 6 patients. Large-scale mtDNA deletions were detected in 3 out of 6 PEO patients and mutations in the POLG1 gene in 1 out of 6. We did not find any mutations in the ANT1, PEO1 or POLG2 genes.

CONCLUSIONS

Our results suggest that molecular investigation of patients with PEO, either sporadic or familial, should start with an analysis for mtDNA deletions, followed by an analysis of the POLG1 gene.

Psychiatric (axis I) and personality (axis II) disorders in patients with burning mouth syndrome or atypical facial pain

Background and aims

Burning mouth syndrome (BMS) and atypical facial pain (AFP) are often persistent idiopathic pain conditions that mainly affect middle-aged and elderly women. They have both been associated with various psychiatric disorders. This study examined current and lifetime prevalence of psychiatric axis I (symptom-based) and II (personality) disorders in patients with chronic idiopathic orofacial pain, and investigated the temporal relationship of psychiatric disorders and the onset of orofacial pain.

Method

Forty patients with BMS and 23 patients with AFP were recruited from Turku university hospital clinics. Mean age of the patients was 62.3 years (range 35–84) and 90% were female. BMS and AFP diagnoses were based on thorough clinical evaluation, and all patients had undergone clinical neurophysiological investigations including blink reflex and thermal quantitative tests. Current and lifetime DSM-IV diagnoses of axis I and II disorders were made on clinical basis with the aid of SCID-I and II-interviews. The detected prevalence rates and their 95% confidence intervals based on binomial distribution were compared to three previous large population-based studies.

Results

Of the 63 patients, 26 (41.3%) had had an axis I disorder that preceded the onset of orofacial pain, and 33 (52.4%) had had a lifetime axis I disorder. Rate of current axis I disorders was 36.5%, indicating that only about 16% of lifetime disorders had remitted, and they tended to run chronic course. The most common lifetime axis I disorders were major depression (30.2%), social phobia (15.9%), specific phobia (11.1%), and panic disorder (7.9%). Twelve patients (19.0%) had at least one cluster C personality disorder already before the emergence of orofacial pain. Patients with cluster C personality disorders are characterized as fearful and neurotic. None of the patients had cluster A (characterized as odd and eccentric) or B (characterized as dramatic, emotional or erratic) personality disorders. The most common personality disorders were obsessive–compulsive personality (14.3%), dependent personality (4.8%), and avoidant personality (3.2%). The majority of the patients (54%) had also one or more chronic pain conditions other than orofacial pain. In almost all patients (94%) they were already present at the onset of orofacial pain.

Conclusions

Our results suggest that major depression, persistent social phobia, and neurotic, fearful, and obsessive–compulsive personality characteristics are common in patients with chronic idiopathic orofacial pain. Most psychiatric disorders precede the onset of orofacial pain and they tend to run a chronic course.

Implications

We propose that the high psychiatric morbidity, and comorbidity to other chronic pain conditions, in chronic idiopathic orofacial pain can be best understood in terms of shared vulnerability to both chronic pain and specific psychiatric disorders, most likely mediated by dysfunctional brain dopamine activity.

Accuracy of protein hydropathy predictions

Hydropathy is a dominant force in protein folding. Sequence-based hydropathy predictions are widely used, without knowledge about their accuracy and reliability. We investigated the prediction accuracy of 56 hydropathy scales by correlating predicted values with the accessible surface area in known protein structures. Results for different amino acids vary greatly within each scale. We also investigated prediction accuracies of amino acids separately in secondary structural elements and in protein fold families. Despite very low overall correlation, hydropathy predictions can still be used if the shape of the plot is important instead of the prediction values.

[Screening for hearing loss in newborns at Turku University Central Hospital]

BACKGROUND

Since 2005 all newborns at Turku University Central Hospital, Finland have been screened for hearing loss with two-stage procedure (otoacoustic emission and automated auditory brainstem response).

METHODS

We reviewed medical records of all newborns screened for hearing loss in 2006-2008. Costs of the screening were estimated.

RESULTS

12011 newborns were screened. In 12 newborns moderate to severe bilateral hearing defect was detected. The incidence of hearing defect was 0.06% among healthy newborns and 0.8% among very preterm infants. Costs of the two-stage screening were 26% lower than those of the one-stage model.

CONCLUSIONS

Two-stage screening for hearing improved identification of newborns with hearing loss in a cost-effective manner.

Acoustic and neurophysiologic observations related to lingual nerve impairment

The purpose of this study was to determine the acoustic effects of lingual nerve impairment on speech. Neurophysiologic examination and thermal quantitative sensory testing (QST) were carried out to determine if the profile, type or severity of sensory nerve impairment had effects on the degree of speech changes. The study group consisted of 5 women and 5 men with lingual nerve damage following an oral and maxillofacial surgery procedure. Time interval between the examination and the nerve damage ranged from 1 month to 20 years. Formants and fundamental frequency and duration of vowel sounds were analyzed. The patients underwent sensory tests, blink reflex and thermal QST of the lingual nerve area. The lingual nerve impairment had effects on the central acoustic features of vowel sounds. A relationship was observed between warm detection threshold values and the magnitude of second formant changes in men. It is concluded that lingual nerve impairment has gender-specific effects on speech. The variability in the acoustic changes of vowel sounds between different patients indicates individual compensatory manners of speech production following lingual nerve impairment.

[Mitochondrial disorder underlying headache symptoms]

MERRF (myoclonic epilepsy with ragged red fibers) is a rare mitochondrial disorder affecting the function of several distinct organs. Diagnosis of the syndrome has conventionally been made on the basis of the patient's myoclonic epilepsy and the so-called ragged red fibers observed in the patient's muscle biopsy. The diagnosis is confirmed by mutation analysis. Symptoms and findings vary from patient to patient even within one family. A strain-associated headache episode and bout of nausea with deficiency symptoms occurs as the most severe symptom in the young boy of our case report.

Kalman smoother based time-varying spectrum estimation of EEG during single agent propofol anesthesia

A time-varying parametric spectrum estimation method for analyzing EEG dynamics is presented. EEG signals are first modeled as a time-varying auto-regressive stochastic process and the model parameters are estimated recursively with a Kalman smoother algorithm. Time-varying spectrum estimates are then obtained from the estimated parameters. The proposed method was applied to measurements collected during low dose propofol anesthesia. The method was able to detect changes of event related (de)synchronization type elicited by verbal command.

Electroencephalogram spindle activity during dexmedetomidine sedation and physiological sleep

BACKGROUND

Dexmedetomidine, a selective alpha(2)-adrenoceptor agonist, induces a unique, sleep-like state of sedation. The objective of the present work was to study human electroencephalogram (EEG) sleep spindles during dexmedetomidine sedation and compare them with spindles during normal physiological sleep, to test the hypothesis that dexmedetomidine exerts its effects via normal sleep-promoting pathways.

METHODS

EEG was continuously recorded from a bipolar frontopolar-laterofrontal derivation with Entropy Module (GE Healthcare) during light and deep dexmedetomidine sedation (target-controlled infusions set at 0.5 and 3.2 ng/ml) in 11 healthy subjects, and during physiological sleep in 10 healthy control subjects. Sleep spindles were visually scored and quantitatively analyzed for density, duration, amplitude (band-pass filtering) and frequency content (matching pursuit approach), and compared between the two groups.

RESULTS

In visual analysis, EEG activity during dexmedetomidine sedation was similar to physiological stage 2 (S2) sleep with slight to moderate amount of slow-wave activity and abundant sleep spindle activity. In quantitative EEG analyses, sleep spindles were similar during dexmedetomidine sedation and normal sleep. No statistically significant differences were found in spindle density, amplitude or frequency content, but the spindles during dexmedetomidine sedation had longer duration (mean 1.11 s, SD 0.14 s) than spindles in normal sleep (mean 0.88 s, SD 0.14 s; P=0.0014).

CONCLUSIONS

Analysis of sleep spindles shows that dexmedetomidine produces a state closely resembling physiological S2 sleep in humans, which gives further support to earlier experimental evidence for activation of normal non-rapid eye movement sleep-promoting pathways by this sedative agent.

Correlation of EEG spectral entropy with regional cerebral blood flow during sevoflurane and propofol anaesthesia

ENTROPY index monitoring, based on spectral entropy of the electroencephalogram, is a promising new method to measure the depth of anaesthesia. We examined the association between spectral entropy and regional cerebral blood flow in healthy subjects anaesthetised with 2%, 3% and 4% end-expiratory concentrations of sevoflurane and 7.6, 12.5 and 19.0 microg.ml(-1) plasma drug concentrations of propofol. Spectral entropy from the frequency band 0.8-32 Hz was calculated and cerebral blood flow assessed using positron emission tomography and [(15)O]-labelled water at baseline and at each anaesthesia level. Both drugs induced significant reductions in spectral entropy and cortical and global cerebral blood flow. Midfrontal-central spectral entropy was associated with individual frontal and whole brain blood flow values across all conditions, suggesting that this novel measure of anaesthetic depth can depict global changes in neuronal activity induced by the drugs. The cortical areas of the most significant associations were remarkably similar for both drugs.

Rehabilitation of chronic post-stroke visual field defect with computer-assisted training: a clinical and neurophysiological study

PURPOSE

Our aim was to study whether homonymous visual field defects could be restored in chronic stroke patients (N = 5) using computer-assisted training, and whether the possible beneficial effect could be maintained. Visual evoked potential (VEP) recordings were applied to evaluate whether they could demonstrate the possible training effects at the cortical level.

METHODS

We applied a specially designed computer program in the training. Subjective assessment, static and kinetic perimetry, and pattern reversal hemifield VEP recordings were used to detect the possible changes.

RESULTS

Two patients showed improvements immediately after the training in static perimetry. Further improvements were detected at a later follow-up in three patients. With kinetic perimetry, improvements were detected in three patients. The visual field defect was detected with VEP recordings in four patients before the training, and improvements could be verified with the method in three patients, two of which clearly improved in the static perimetry as well.

CONCLUSIONS

In three patients, the visual defect diminished with the computer-assisted method. It seems evident that visual field defects resulting from stroke can be partially restored even in the chronic phase.

An evaluation of clinical and electrophysiologic tests in nerve injury diagnosis after mandibular sagittal split osteotomy

The yield of clinical sensory tests and electrophysiologic tests in the diagnostics of inferior alveolar nerve (IAN) damage after bilateral sagittal split osteotomy (BSSO) was studied. The diagnostic value of these tests was evaluated by comparing the test results to the degree of nerve damage at the end of the operation as documented by means of the intraoperative nerve conduction recording of the IAN. Twenty patients undergoing BSSO were analysed preoperatively and 2 weeks postoperatively. The frequency of the IAN disturbance ranged from 10% to 94% depending on the test method and the test site used. Of the clinical sensory tests, the touch detection threshold (TD) test was the most sensitive and clinically useful test. It also correlated best with the electrophysiologically verified intraoperative nerve damage (R = -0.603, P = 0.017 on the right, R = -0.626, P = 0.01 on the left). The blink reflex and quantitative cold detection threshold tests were almost as often abnormal as the TD-test, but nerve conduction study (NCS) was the most sensitive (88%) of all clinical and electrophysiologic tests. The frequency of abnormal findings in the electrophysiologic tests indicating IAN injury, 75% on the right side and 90% on the left side, corresponded exactly with the figures of subjective sensory alteration. Almost all electrophysiologic tests showed obvious associations with the objectively verified IAN damage. All tests, except the NCS, showed only moderate sensitivity. Specificity of the tests was generally high, the only exceptions being the TD test and the NCS. To increase the diagnostic accuracy of the testing and to detect different types of damage in different nerve fibre populations, a combination of different sensory and electrophysiologic tests is recommended.

Striatal dopamine D1 and D2 receptors in burning mouth syndrome

Animal studies have indicated that the nigrostriatal dopaminergic system is involved in central pain modulation. In a recent positron emission tomography (PET) study, we demonstrated presynaptic dysfunction of the nigrostriatal dopaminergic pathway in burning mouth syndrome, which is a chronic pain state. The objective of the present study was to examine striatal dopamine D1 and D2 receptors in these patients. We used 11C-NNC 756 and 11C-raclopride to study D1 and D2 receptor binding in a PET study in ten burning mouth patients and 11 healthy controls. Patients underwent a structured psychiatric evaluation and an electrophysiological test for the excitability of the blink reflex. The striatal uptake of 11C-NNC 756 did not differ between patients and controls. In a voxel-level analysis, the uptake of 11C-raclopride was statistically significantly higher in the left putamen in burning mouth patients (corrected P-value 0.038 at cluster-level). In the region of interest analysis, the D1/D2 ratio was 7.7% lower in the right putamen (0.64+/-0.04 vs. 0.69+/-0.04, P=0.01) and 6.4 % lower in the left putamen (0.65+/-0.05 vs. 0.70+/-0.05, P=0.05) when compared to controls. Increased 11C-raclopride uptake and the subsequent decrease in the D1/D2 ratio may indicate a decline in endogenous dopamine levels in the putamen in burning mouth patients.

Peripheral nervous system in gyrate atrophy of the choroid and retina with hyperornithinemia

OBJECTIVE

To evaluate peripheral nervous system involvement in gyrate atrophy of the choroid and retina with hyperornithinemia (GA).

BACKGROUND

GA is an inborn error of amino acid metabolism caused by mutations in the enzyme ornithine aminotransferase. Patients with GA have hyperornithinemia, progressive centripetal loss of vision, minor CNS abnormalities, and type II muscle fiber atrophy with accumulation of tubular aggregates. The authors previously showed that muscle and brain creatine stores are depleted in the patients with GA.

METHODS

The authors searched evidence of peripheral nervous involvement in 40 patients with GA (mean age 31.6 +/- 16.3 years; range 5 to 74 years) by using neurography, quantitative sensory threshold testing, and evoked potential testing.

RESULTS

Neurography revealed abnormalities in 21 (53%) of the patients. The abnormalities associated with the severity of the ophthalmologic changes and the age of the patients. With quantitative sensory threshold testing, abnormal large-fiber function was found in seven (18%) and abnormal small-fiber function was found in four (10%) patients. Somatosensory evoked potential and brainstem auditory evoked potential responses were abolished in five patients.

CONCLUSIONS

These findings of peripheral nervous system involvement in GA suggest that GA is a systemic disease affecting not only CNS but also the peripheral nervous system.

Sensory dysfunction in burning mouth syndrome

Our preliminary observations on a small group of burning mouth syndrome (BMS) patients indicated a change in the non-nociceptive, tactile sensory function in BMS and provided evidence for the hypothesis of a neuropathic etiology of BMS. In the present clinical study on a group of 52 BMS patients, we used quantitative sensory tests (QST) in addition to the blink reflex (BR) recordings in order to gain further insight into the neural mechanisms of BMS pain. Based on electrophysiologic findings, the BMS patients could be grouped into four different categories: (1) The results of the BR were suggestive of brainstem pathology or peripheral trigeminal neuropathy in ten (19%) patients. In most of the cases, the abnormalities in the BR seemed to represent subclinical changes of the trigeminal system. (2) Increased excitability of the BR was found in the form of deficient habituation of the R2 component of the BR in 11 (21%) of the patients. Two of these patients also showed signs of warm allodynia in QST. (3) One or more of the sensory thresholds were abnormal indicating thin fiber dysfunction in altogether 35 patients (76%) out of the 46 tested with QST. Thirty-three of these patients showed signs of hypoesthesia. (4) There were only five patients with normal findings in both tests. The present findings with strong evidence for neuropathic background in BMS will hopefully provide insights for new therapeutic strategies.

Effects of surgical levels of propofol and sevoflurane anesthesia on cerebral blood flow in healthy subjects studied with positron emission tomography

BACKGROUND

The authors report a positron emission tomography (PET) study on humans with parallel exploration of the dose-dependent effects of an intravenous (propofol) and a volatile (sevoflurane) anesthetic agent on regional cerebral blood flow (rCBF) using quantitative and relative (Statistical Parametric Mapping [SPM]) analysis.

METHODS

Using H(2)(15)O, rCBF was assessed in 16 healthy (American Society of Anesthesiologists [ASA] physical status I) volunteers awake and at three escalating drug concentrations: 1, 1.5, and 2 MAC/EC(50), or specifically, at either 2, 3, and 4% end-tidal sevoflurane (n = 8), or 6, 9, and 12 microg/ml plasma concentration of propofol (n = 8). Rocuronium was used for muscle relaxation.

RESULTS

Both drugs decreased the bispectral index and blood pressure dose-dependently. Comparison between adjacent levels showed that sevoflurane initially (0 vs. 1 MAC) reduced absolute rCBF by 36-53% in all areas, then (1 vs. 1.5 MAC) increased rCBF in the frontal cortex, thalamus, and cerebellum (7-16%), and finally (1.5 vs. 2 MAC) caused a dual effect with a 23% frontal reduction and a 38% cerebellar increase. In the propofol group, flow was also initially reduced by 62-70%, with minor further effects. In the SPM analysis of the "awake to 1 MAC/EC(50)" step, both anesthetic agents reduced relative rCBF in the cuneus, precuneus, posterior limbic system, and the thalamus or midbrain; additionally, propofol reduced relative rCBF in the parietal and frontal cortices.

CONCLUSIONS

Both anesthetic agents caused a global reduction of rCBF (propofol > sevoflurane) at the 1 MAC/EC(50) level. The effect was maintained at higher propofol concentrations, whereas 2 MAC sevoflurane caused noticeable flow redistribution. Despite the marked global changes, SPM analysis enabled detailed localization of regions with the greatest relative decreases.

[18F]FDG-PET reveals temporal hypometabolism in patients with temporal lobe epilepsy even when quantitative MRI and histopathological analysis show only mild hippocampal damage

BACKGROUND

The relationship between reduced glucose metabolism in positron emission tomography with fludeoxyglucose F 18 ([(18)F]FDG-PET) and hippocampal damage (HD) in patients with temporal lobe epilepsy is still unclear.

OBJECTIVE

To determine whether the presence and severity of HD verified by quantitative magnetic resonance imaging (QMRI) and histopathological analysis affect the degree of hypometabolism.

PATIENTS AND METHODS

Sixteen patients with drug-resistant temporal lobe epilepsy underwent [(18)F]FDG-PET and QMRI (hippocampal volumetry and T2 relaxometry) before surgery. Histopathological analysis of the hippocampus included measurements of neuronal loss, proliferation of glial cells, and mossy fiber sprouting. The asymmetry in glucose metabolism described the degree of hypometabolism.

RESULTS

Temporal hypometabolism was not related to severity of HD as measured by QMRI or histopathological analysis. The degree of hypometabolism did not differ in patients with mild, moderate, or severe HD. In addition, [(18)F]FDG-PET revealed significant temporal hypometabolism even though hippocampal QMRI findings were normal or showed only mild HD. Thus, glucose consumption was reduced over and above the histopathological changes.

CONCLUSIONS

[(18)F]FDG-PET is sensitive for localizing the epileptogenic region in patients with temporal lobe epilepsy. However, it is insensitive to reflect the severity of HD.

Ophthalmologic heterogeneity in subjects with gyrate atrophy of choroid and retina harboring the L402P mutation of ornithine aminotransferase

OBJECTIVE/PURPOSE

To investigate clinical variation in a genetically homogenous group of subjects with gyrate atrophy of choroid and retina with hyperornithinemia (GA). The group was made up of homozygotes and compound heterozygotes for mutation L402P in the ornithine aminotransferase (OAT) gene.

DESIGN

Cross-sectional study.

PARTICIPANTS

Thirty-five Finnish subjects (18 men) with GA with a mean age of 33 years (range, 5-74 years) carrying the Finnish founder mutation L402P.

METHODS

All subjects were examined between 1993 and 1995. The analysis was composed of, in addition to careful clinical evaluation, studies of visual fields with Goldmann perimeter, photographing of the eye fundi, and corneal electroretinography (ERG) recordings.

MAIN OUTCOME MEASURES

The changes in eye fundi, visual acuity, cataract changes in the lens, visual field constriction, and ERG responses were determined.

RESULTS

Myopia, early cataracts, and highly abnormal ERG were typical for the GA subjects. The changes progressed rather uniformly with age. However, visual acuity, funduscopic findings, and visual fields showed great phenotypic variation. Despite the great interindividual variation, both eyes of each subject were always similarly affected.

CONCLUSIONS

This study of 35 subjects with GA carrying a single mutation shows that the ophthalmologic symptoms and findings vary widely. The data also reveal that GA subjects are already affected by severe visual impairment in young adulthood. However, the diagnosis is often made very late.

Central and peripheral nervous system dysfunction in the clinical variation of Salla disease

OBJECTIVE

To evaluate the degree of possible peripheral nervous system (PNS) involvement in addition to CNS manifestations in Salla disease, a free sialic acid storage disorder leading to severe mental retardation with a wide clinical variation.

BACKGROUND

Salla disease is a lysosomal storage disorder that affects the white matter of the CNS. MRI findings and recent 1H MRS study results provide evidence for delayed central myelination, but there is no previous evidence for PNS involvement in this disease. The gene coding for a presumptive sialic acid transport protein has recently been identified, and the first disease-causing mutations have been characterized.

METHODS

Nerve conduction studies; evoked potentials to visual (VEP), brainstem auditory (BAEP), and somatosensory stimuli (SEP); and EEG were carried out on 22 patients (age range 2 months to 57 years) with biochemically and genetically confirmed Salla disease. Brain MRI were available on 14 patients.

RESULTS

Nerve conduction studies revealed abnormalities in nearly half of the patients (10/21). The four severely disabled patients and the oldest patient had greatly reduced nerve conduction velocities and prolonged distal latencies compatible with demyelinating polyneuropathy. In addition, SEP was abnormal in the majority of the patients, but VEP and BAEP in only a few cases. PNS involvement was clearly associated with both the phenotypic severity and MRI findings.

CONCLUSIONS

The results indicate that dysmyelination in Salla disease occurs not only in the CNS but also in the peripheral nervous system, contributing to the phenotypic variation, which can now be correlated with the molecular basis of the disease.

Habituation of the blink reflex in first-episode schizophrenia, psychotic depression and non-psychotic depression

OBJECTIVE

Electrophysiological recording of the electrically elicited blink reflex is the most reliable method of investigating habituation of the startle reflex. The purpose of this study was to compare the habituation and the late R3-component of the blink reflex between control subjects (N=19) and first-episode patients with schizophrenia (N=17), psychotic depression (N=23), and severe non-psychotic depression (N=25).

METHODS

The blink reflex was evoked by electrical stimulation of the supraorbital nerve, and the deficient habituation of the R2i-component was measured with a computer-assisted integral area measurement. Prefrontal executive function of the patients was assessed with the Wisconsin Card Sorting Test. Current psychiatric symptoms were assessed with the Brief Psychiatric Rating Scale, the Hamilton Depression Scale, the Positive and Negative Syndrome Scale, and the Calgary Depression Scale.

RESULTS

Deficient habituation of the blink reflex and occurrence of the late R3 component were associated both with a previous diagnosis of psychotic disorder and with the presence of current psychosis. The sensitivity and specificity of the abnormal habituation of the blink reflex in detecting psychotic disorder were 0.50 and 0.80, respectively. The abnormalities of the blink reflex were not associated with psychotropic medication. In schizophrenic patients, defective habituation of the blink reflex was associated with negative and cognitive symptoms, and in depressive patients with the presence of delusions.

CONCLUSIONS

The deficient habituation of the blink reflex and occurrence of the late R3 component seem to be both trait and state markers of a psychotic disorder. The results suggest that schizophrenia and psychotic depression share some common neurobiological mechanisms involved in the modulation of the startle reflex.

Central nervous system involvement in gyrate atrophy of the choroid and retina with hyperornithinaemia

In gyrate atrophy of the choroid and retina with hyperornithinaemia (GA), a genetically determined deficiency of ornithine delta-aminotransferase activity leads to high ornithine concentrations in body fluids. GA is characterized by centripetally progressing retinal and choroidal destruction and selective atrophy with tubular aggregates in type II skeletal muscle fibres. These findings have been suggested to be mediated by hyperornithinaemia-induced deficiency of high-energy creatine phosphate. As abnormal brain magnetic resonance images and electroencephalograms are found in another disorder of creatine metabolism, guanidinoacetate methyltransferase deficiency, we investigated the central nervous system involvement in GA, which seems to be associated with a milder degree of phosphocreatine deficiency. We compared 23 untreated GA patients with age-matched healthy controls, and with 9 patients who had received creatine or creatine precursor supplementation daily for several years. The mean age of the patients (32 +/- 18 years) was similar to that of the controls (36 +/- 22 years). The MRI or EEG findings of the patients on creatine supplementation did not differ from those of the untreated group. Brain MRI revealed degenerative lesions in the white matter in 50% of the GA patients, and 70% of the patients had premature atrophic changes, with a striking increase in the number of Virchow's spaces. Of the patients whose EEG was recorded, 58% had abnormal slow background activity, focal lesions or high-amplitude beta rhythm (> 50 microV). The EEG findings were not associated with the MRI changes or with the age or the sex of the patients. Early degenerative and atrophic brain changes and abnormal EEG are thus features of GA, in addition to the well-characterized eye and muscle manifestations.

Increased brain glucose utilization in Salla disease (free sialic acid storage disorder)

Salla disease is an autosomal recessive lysosomal free sialic acid storage disorder characterized by psychomotor retardation and ataxia. MRI studies have revealed evidence of dysmyelination, but the biological mechanism of the brain dysfunction is unknown.

METHODS

Nine patients with Salla disease (age 2.5 mo-42 y) presenting the disease in varying degrees of severity were studied by PET using 2-fluoro-2-deoxy-D-glucose (FDG) as a tracer. Local cerebral metabolic rates for glucose (LCMRGlc) in individual brain regions were compared with controls.

RESULTS

The FDG PET results showed significantly increased LCMRGlc values in the frontal and sensorimotor cortex and especially in the basal ganglia of the patients. Cerebellar hypometabolism was present in all seven patients with marked ataxia, whereas the less severely affected patients without obvious ataxia had normal or even high glucose uptake in the cerebellum.

CONCLUSION

The increased cerebral glucose utilization is a constant finding in Salla disease and may reflect the basic defect of the sialic acid metabolism in this disorder. The FDG PET findings in the cerebellum suggest a correlation between glucose uptake and the severity of the clinical symptoms.

Conformational change in the activation of lipase: an analysis in terms of low-frequency normal modes

The interfacial activation of Rhizomucor miehei lipase (RmL) involves the motion of an alpha-helical region (residues 82-96) which acts as a "lid" over the active site of the enzyme, undergoing a displacement from a "closed" to an "open" conformation upon binding of substrate. Normal mode analyses performed in both low and high dielectric media reveal that low-frequency vibrational modes contribute significantly to the conformational transition between the closed and open conformations. In these modes, the lid displacement is coupled to local motions of active site loops as well as global breathing motions. Atomic fluctuations of the first hinge of the lid (residues 83-84) are substantially larger in the low dielectric medium than in the high dielectric medium. Our results also suggest that electrostatic interactions of Arg86 play an important role in terms of both the intrinsic stability of the lid and its displacement, through enhancement of hinge mobility in a high dielectric medium. Additional calculations demonstrate that the observed patterns of atomic fluctuations are an intrinsic feature of the protein structure and not dependent on the nature of specific energy minima.

Low field T1rho imaging of myositis

The purpose of this study was to evaluate 1/T1rho in relation to 1/T1 and 1/T2 in characterizing normal and diseased muscle. We measured the muscle relaxation rates 1/T1 and 1/T2 at 0.1 T and 1/T1rho at on-resonance locking fields B1 between 10 and 160 microT in myositis patients and normal volunteers. 1/T2 and 1/T1rho of muscle were lower in the patients than in the volunteers, whereas there was no difference in the 1/T1 values. The lower relaxation rates 1/T2 and 1/T1rho in the diseased muscle may be due to fat and connective tissue infiltrations and edema. 1/T1rho contrast between muscle and subcutaneous fat was higher than 1/T2 and 1/T1 contrast. This may be explained by the different B1 dispersion behavior of these two tissue types. 1/T1rho of fat is B1 field independent, whereas 1/T1rho of muscle decreases clearly with increasing B1 field. In conclusion, 1/T1rho provides a useful tool in manipulating contrast in magnetic resonance imaging of diseased muscle.

Comparison of [18F]FDG-PET, [99mTc]-HMPAO-SPECT, and [123I]-iomazenil-SPECT in localising the epileptogenic cortex

OBJECTIVES

Firstly, to compare the findings of interictal 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and of single photon emission computed tomography (SPECT) using 99mTc-hexamethyl propylene-amine-oxime (HMPAO) and 123I-iomazenil in localising the epileptogenic cortex in patients who were candidates for epilepsy surgery, but in whom clinical findings, video EEG monitoring (V-EEG), MRI, and neuropsychological evaluations did not give any definite localisation of the seizure onset. Secondly, to assess the ability of these functional methods to help in the decision about the epilepsy surgery.

METHODS

Eighteen epileptic patients were studied with FDG-PET and iomazenil-SPECT. HMPAO-SPECT was performed in 11 of these 18 patients. Two references for localisation was used--ictal subdural EEG recordings (S-EEG) and the operated region.

RESULTS

Fifteen of 18 patients had localising findings in S-EEG. FDG-PET findings were in accordance with the references in 13 patients and iomazenil-SPECT in nine patients. HMPAO-SPECT visualised the focus less accurately than the two other methods. In three patients S-EEG showed independent bitemporal seizure onset. In these patients FDG-PET showed no lateralisation. However, iomazenil-SPECT showed temporal lobe lateralisation in two of them.

CONCLUSION

FDG-PET seemed to localise the epileptogenic cortex more accurately than interictal iomazenil-SPECT in patients with complicated focal epilepsy.

Inter-hospital comparison of Ganzfeld ERG photostimulators

The periodic calibration and control of electroretinographic (ERG) stimulators is often neglected due to the difficulties in accurate measurements of the stimuli. Comparison of measurements carried out in different laboratories has been very difficult, as the accurate parameters of the stimuli used usually are not known. In some cases it is assumed that if the stimulator type is known, comparisons can be carried out. We have tested the Ganzfeld flash stimulators used in the departments of clinical neurophysiology of 3 major hospitals in Finland, namely Kuopio University Hospital, Turku Central University Hospital, and Tampere University Hospital, Measurements, performed with a new type of photometer, show that the intensities varied by 42% between the highest and lowest intensity stimulators at nominally identical settings. The measurements underline the findings that identical stimulators will not necessarily produce identical stimuli. These observations also indicate that the stability of the stimuli can be improved by the proper choice of stimulator output settings.

Peripheral neuromuscular manifestations in systemic sclerosis (scleroderma)

Systemic sclerosis (scleroderma) is thought to be the least likely of the collagen vascular disorders to cause nervous system damage. We evaluated the peripheral neuromuscular manifestations in 32 patients with scleroderma. A clinically defined peripheral nervous system (PNS) lesion was manifest in 5 of 32 patients (16%), including 2 patients with trigeminal neuropathy and single cases of polyneuropathy, brachial plexopathy, and lumbosacral radiculopathy. Neurophysiological studies suggested subclinical PNS involvement in 6 additional patients (3 with distal axonal polyneuropathy, 1 with probable myopathy and superimposed polyneuropathy, 1 with trigeminal neuropathy, and 1 with focal ulnar neuropathy). Even though subjective muscular complaints were numerous (16 patients, 50%), a defined primary muscular disease could be demonstrated only in 5 patients (16%). Our results indicate that peripheral neuropathy in scleroderma is not as uncommon as previously estimated.

An aminoterminally extended P1-protamine variant in the boar

We have found a minor form of boar sperm P1-protamine with a six amino acid long N-terminal extension. When this sequence was compared with the recently published gene sequence of boar P1-protamine, and with DNA sequences obtained from the boars studied here, a perfect match was found with the 5'-region upstream of the ATG initiation codon of the authentic P1-protamine. Since no extra in-frame ATG initiation codons are present in the 5'-region of the gene, we conclude that the translation of boar P1-protamine variant starts with a non-AUG initiation codon, CUG, which precedes the codon of the first amino acid (serine) of the sequenced variant.

Central nervous system involvement and psychiatric manifestations in systemic sclerosis (scleroderma): clinical and neurophysiological evaluation

We evaluated central nervous system and psychiatric involvement in a clinical sample of 32 patients with systemic sclerosis (SSc) (scleroderma). All patients underwent clinical neurological examination. Electroencephalography (EEG) and visual evoked potentials (VEPs) were also recorded. Prominent central nervous system (CNS) or psychiatric symptoms were present in 5 patients (16%), including encephalopathy, psychosis, anxiety disorder, grand mal seizures and transient ischemic attack. In addition, abnormal VEPs were recorded from 5/32 patients (16%), suggesting optic neuropathy. EEGs were mainly normal or showed only slight, nonspecific changes. Primary CNS involvement in scleroderma, however, could not be shown in any of the 5 cases with neuropsychiatric symptoms. Our results suggest that neuropsychiatric symptoms in SSc are, if not coincidental, indirectly caused by internal organ involvement of SSc or by possible overlapping connective tissue diseases. On the other hand, optic neuropathy might be a primary complication of SSc.