Longitudinal Speech Outcome at 5 and 10 Years in UCLP: Influence of Speech Therapy and Secondary Velopharyngeal Surgery

OBJECTIVE

To investigate speech development of children aged 5 and 10 years with repaired unilateral cleft lip and palate (UCLP) and identify speech characteristics when speech proficiency is not at 'peer level' at 10 years. Estimate how the number of speech therapy visits are related to speech proficiency at 10 years, and what factors are predictive of whether a child's speech proficiency at 10 years is at 'peer level' or not.

DESIGN

Longitudinal complete datasets from the Scandcleft project.

PARTICIPANTS

320 children from nine cleft palate teams in five countries, operated on with one out of four surgical methods.

INTERVENTIONS

Secondary velopharyngeal surgery (VP-surgery) and number of speech therapy visits (ST-visits), a proxy for speech intervention.

MAIN OUTCOME MEASURES

'Peer level' of percentage of consonants correct (PCC, > 91%) and the composite score of velopharyngeal competence (VPC-Sum, 0-1).

RESULTS

Speech proficiency improved, with only 23% of the participants at 'peer level' at 5 years, compared to 56% at 10 years. A poorer PCC score was the most sensitive marker for the 44% below 'peer level' at 10-year-of-age. The best predictor of 'peer level' speech proficiency at 10 years was speech proficiency at 5 years. A high number of ST-visits received did not improve the probability of achieving 'peer level' speech, and many children seemed to have received excessive amounts of ST-visits without substantial improvement.

CONCLUSIONS

It is important to strive for speech at 'peer level' before age 5. Criteria for speech therapy intervention and for methods used needs to be evidence-based.

Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate: Speech proficiency at 10 years of age

BACKGROUND & AIM

To assess consonant proficiency and velopharyngeal function in 10-year-old children born with unilateral cleft lip and palate (UCLP) within the Scandcleft project.

METHODS & PROCEDURES

Three parallel group, randomized, clinical trials were undertaken as an international multicentre study by nine cleft teams in five countries. Three different surgical protocols for primary palate repair (Arm B-Lip and soft palate closure at 3-4 months, hard palate closure at 36 months, Arm C-Lip closure at 3-4 months, hard and soft palate closure at 12 months, and Arm D-Lip closure at 3-4 months combined with a single-layer closure of the hard palate using a vomer flap, soft palate closure at 12 months) were tested against a common procedure (Arm A-Lip and soft palate closure at 3-4 months followed by hard palate closure at 12 months) in the total cohort of 431 children born with a non-syndromic UCLP. Speech audio and video recordings of 399 children were available and perceptually analysed. Percentage of consonants correct (PCC) from a naming test, an overall rating of velopharyngeal competence (VPC) (VPC-Rate), and a composite measure (VPC-Sum) were reported.

OUTCOMES & RESULTS

The mean levels of consonant proficiency (PCC score) in the trial arms were 86-92% and between 58% and 83% of the children had VPC (VPC-Sum). Only 50-73% of the participants had a consonant proficiency level with their peers. Girls performed better throughout. Long delay of the hard palate repair (Arm B) indicated lower PCC and simultaneous hard and soft palate closure higher (Arm C). However, the proportion of participants with primary VPC (not including velopharyngeal surgeries) was highest in Arm B (68%) and lowest in Arm C (47%).

CONCLUSIONS & IMPLICATIONS

The speech outcome in terms of PCC and VPC was low across the trials. The different protocols had their pros and cons and there is no obvious evidence to recommend any of the protocols as superior. Aspects other than primary surgical method, such as time after velopharyngeal surgery, surgical experience, hearing level, language difficulties and speech therapy, need to be thoroughly reviewed for a better understanding of what has affected speech outcome at 10 years.

WHAT THIS PAPER ADDS

What is already known on the subject Speech outcomes at 10 years of age in children treated for UCLP are sparse and contradictory. Previous studies have examined speech outcomes and the relationship with surgical intervention in 5-year-olds. What this study adds to the existing knowledge Speech outcomes based on standardized assessment in a large group of 10-year-old children born with UCLP and surgically treated according to different protocols are presented. While speech therapy had been provided, a large proportion of the children across treatment protocols still needed further speech therapy. What are the potential or actual clinical implications of this work? Aspects other than surgery and speech function might add to the understanding of what affects speech outcome. Effective speech therapy should be available for children in addition to primary surgical repair of the cleft and secondary surgeries if needed.

Differential willingness for genetic testing to target treatment in older Danish citizens

Background

Studies from different countries have shown that population majorities are willing to accept genetic tests for treatment personalisation and that considerable proportions are ready to donate their data to research. However, it has also been shown that concerns, for example about data use and confidentiality or treatment rationing, are common. To enable a more targeted communication process with the public about personalized medicine, more knowledge is needed on views in different sub-populations. In the present study, a hypothetical scenario was used to investigate differential readiness to accept a genetic test for treatment targeting and to permit use of personal data for research.

Methods

A cross-sectional survey was conducted with 50-80-year-old Danish citizens (n = 6807) who were sampled to represent the Danish population in that age segment. Socio-demographic data were added from a national registry. Data were analyzed by multivariable logistic regression analysis.

Results

Preliminary results showed that a majority was willing to be tested (78.3%). Readiness was lower in women [OR = .67; CI = .59-.77] and those 70-80 [OR = .72; CI = 61-.86], while it was higher in those with better income [OR = 1.29; CI = 1.09-1.52]. Further, those less satisfied with their health, the obese and those with a perceived genetic vulnerability were more willing to be tested. Over 90% of those ready to be tested were also willing to permit use of their data for research. Rates were higher in men, older segments, those with higher income/education as well as those with current pain experience and those aware of a personal genetic vulnerability.

Conclusions

Findings indicate group differences in acceptance of a genetic test for personalisation of medicine and data use for research. Further research should investigate group-specific benefit perceptions versus concerns in population subgroups to inform implementation and enable targeted communication strategies.

Key messages

• Acceptance of genetic testing for personalisation of treatment as well as willingness to contribute data to research may differ between population subgroups.

• Women and those with lower income are less willing to accept genetic testing for treatment personalisation and accept research use of data while health vulnerabilities increase acceptance.

P6562The relationship between serum potassium concentrations and electrocardiographic characteristics in 163,547 individuals from primary care

Aims

Potassium disturbances are common and associated with increased morbidity and mortality, even in patients without prior cardiovascular disease. We examined six electrocardiographic (ECG) measures and their association to serum potassium levels.

Methods and results

From the Copenhagen General Practitioners' Laboratory, we identified 163,547 individuals aged ≥16 years with a first available ECG and a concomitant serum potassium measurement during 2001–2011. Restricted cubic splines curves showed a non-linear relationship between potassium and the Fridericia corrected QT (QTcF) interval, T-wave amplitude, morphology combination score (MCS), PR interval, P-wave amplitude and duration. Therefore, potassium was stratified in two intervals K: 2.0–4.1 mmol/L and 4.2–6.0 mmol/L for further analyses. Within the low potassium range, we observed: QTcF was 12.5 ms longer for each mmol/L decrease in potassium (p<0.0001); T-wave amplitude was 55.1 μV lower for each mmol/L decrease in potassium (p<0.0001); and MCS was 0.09 higher per mmol/L decrease in potassium (p<0.001). Moreover, P-wave duration and PR interval were prolonged by 3.1 and 3.3 ms for each mmol/L decrease in potassium (p<0.0001), respectively. Within the lowest potassium range (2.0–4.1 mmol/L) P-wave amplitude was 10.7 μV higher for each mmol/L decrease in potassium (p<0.0001). Within the high potassium range associations with the above-mentioned ECG parameters were much weaker.

Restricted cubic splines on adjusted lin

Conclusion

The association of potassium with six commonly measured ECG parameters was non-linear. Strong associations between ECG abnormalities and potassium were seen among individuals with lower potassium levels (≤4.1 mmol/L).

Acknowledgement/Funding

None

Exploratory analyses of the Danish Palliative Care Trial (DanPaCT): a randomized trial of early specialized palliative care plus standard care versus standard care in advanced cancer patients

BACKGROUND

Early and integrated specialized palliative care is often recommended but has still only been investigated in relatively few randomized clinical trials.

OBJECTIVE

To investigate the effect of early specialized palliative care plus standard care versus standard care on the explorative outcomes in the Danish Palliative Care Trial (DanPaCT).

METHODS

We conducted a randomized multicentre, parallel-group clinical trial. Consecutive patients with metastatic cancer were included if they had symptoms or problems that exceeded a predefined threshold according to the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). Outcomes were estimated as the differences between the intervention and the control groups in the change from baseline to the weighted mean of the 3- and 8-week follow-ups measured as areas under the curve.

RESULTS

In total, 145 patients were randomized to early specialized palliative care plus standard care versus 152 to standard care only. Early specialized palliative care had no significant effect on any of the symptoms or problems. Of the 21 items addressing satisfaction, specialized palliative care improved the item 'overall satisfaction with the help received from the health care system' with 9 points (95% confidence interval 3.8 to 14.2, p = 0.0006) and three other items (all p < 0.05).

CONCLUSION

In line with the analyses of the primary and secondary outcomes in DanPaCT, we did not find that specialized palliative care, as provided in DanPaCT, affected symptoms and problems. However, patients in the intervention group seemed more satisfied with the health care received than those in the standard care group.

TRIAL REGISTRATION

NCT01348048.

Reliability and consistency of a validated sun exposure questionnaire in a population-based Danish sample

An important feature of questionnaire validation is reliability. To be able to measure a given concept by questionnaire validly, the reliability needs to be high.

The objectives of this study were to examine reliability of attitude and knowledge and behavioral consistency of sunburn in a developed questionnaire for monitoring and evaluating population sun-related behavior.

Sun related behavior, attitude and knowledge was measured weekly by a questionnaire in the summer of 2013 among 664 Danes. Reliability was tested in a test-retest design. Consistency of behavioral information was tested similarly in a questionnaire adapted to measure behavior throughout the summer.

The response rates for questionnaire 1, 2 and 3 were high and the drop out was not dependent on demographic characteristic. There was at least 73% agreement between sunburns in the measurement week and the entire summer, and a possible sunburn underestimation in questionnaires summarizing the entire summer. The participants underestimated their outdoor exposure in the evaluation covering the entire summer as compared to the measurement week. The reliability of scales measuring attitude and knowledge was high for majority of scales, while consistency in protection behavior was low.

To our knowledge, this is the first study to report reliability for a completely validated questionnaire on sun-related behavior in a national random population based sample. Further, we show that attitude and knowledge questions confirmed their validity with good reliability, while consistency of protection behavior in general and in a week's measurement was low.

•

Objectively validated questionnaires tested for reliability/behavioral consistency.

•

Strong reliability of the knowledge and attitude items was shown.

•

Knowledge about behavioral consistency between questionnaire measurement periods

•

A recommendable design for short term evaluation of skin cancer prevention campaigns

Variable impact of tizanidine on the medium latency reflex of upper and lower limbs

Sudden limb displacement evokes a complex sequence of compensatory muscle activity. Following the short-latency reflex and preceding voluntary reactions is an epoch termed the medium-latency reflex (MLR) that could reflect spinal processing of group II muscle afferents. One way to test this possibility is oral ingestion of tizanidine, an alpha-2 adrenergic agonist that inhibits the interneurons transmitting group II signals onto spinal motor neurons. We examined whether group II afferents contribute to MLR activity throughout the major muscles that span the elbow and shoulder. MLRs of ankle muscles were also tested during walking on the same day, in the same participants as well as during sitting in a different group of subjects. In contrast to previous reports, the ingestion of tizanidine had minimal impact on MLRs of arm or leg muscles during motor actions. A significant decrease in magnitude was observed for 2/16 contrasts in arm muscles and 0/4 contrasts in leg muscles. This discrepancy with previous studies could indicate that tizanidine's efficacy is altered by subtle changes in protocol or that group II afferents do not substantially contribute to MLRs.

Randomised clinical trial of early specialist palliative care plus standard care versus standard care alone in patients with advanced cancer: The Danish Palliative Care Trial

BACKGROUND

Beneficial effects of early palliative care have been found in advanced cancer, but the evidence is not unequivocal.

AIM

To investigate the effect of early specialist palliative care among advanced cancer patients identified in oncology departments.

SETTING/PARTICIPANTS

The Danish Palliative Care Trial (DanPaCT) (ClinicalTrials.gov NCT01348048) is a multicentre randomised clinical trial comparing early referral to a specialist palliative care team plus standard care versus standard care alone. The planned sample size was 300. At five oncology departments, consecutive patients with advanced cancer were screened for palliative needs. Patients with scores exceeding a predefined threshold for problems with physical, emotional or role function, or nausea/vomiting, pain, dyspnoea or lack of appetite according to the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) were eligible. The primary outcome was the change in each patient's primary need (the most severe of the seven QLQ-C30 scales) at 3- and 8-week follow-up (0-100 scale). Five sensitivity analyses were conducted. Secondary outcomes were change in the seven QLQ-C30 scales and survival.

RESULTS

Totally 145 patients were randomised to early specialist palliative care versus 152 to standard care. Early specialist palliative care showed no effect on the primary outcome of change in primary need (-4.9 points (95% confidence interval -11.3 to +1.5 points); p = 0.14). The sensitivity analyses showed similar results. Analyses of the secondary outcomes, including survival, also showed no differences, maybe with the exception of nausea/vomiting where early specialist palliative care might have had a beneficial effect.

CONCLUSION

We did not observe beneficial or harmful effects of early specialist palliative care, but important beneficial effects cannot be excluded.

Convergence of ipsi- and contralateral muscle afferents on common interneurons mediating reciprocal inhibition of ankle plantarflexors in humans

Recent studies have shown that afferents arising from muscle receptors located on one side can affect the activity of muscles on the contralateral side. In animal preparations, evidence supports that afferent pathways originating from one limb converge onto interneurons mediating disynaptic reciprocal Ia inhibition of the opposite limb. This study was designed to investigate whether this pathway is similar in humans to that described in animals. Thirteen healthy volunteers participated in one of two experiments. In experiment 1, the effects of ipsilateral posterior tibial nerve (iPTN) stimulation were assessed on the reciprocal Ia inhibition of the contralateral soleus (cSOL) motoneuronal pool (n = 8). Across all participants, iPTN stimulation intensity was 1.69 ± 0.3 × Motor Threshold (MT) and contralateral common peroneal (cCPN) stimulation intensity was 0.86 ± 0.16 × MT. iPTN and cCPN stimulation were delivered separately or in combination and changes in the ongoing electromyography (EMG) quantified. In experiment 2, the amplitude of a test SOL H-reflex elicited by contralateral PTN (cPTN) stimulation was quantified following iPTN, cCPN or iPTN + cCPN nerve stimulation (n = 5). Intensities used during the H-reflex conditioning experiment were 1.79 ± 0.4 × MT for the iPTN stimulation and 0.88 ± 0.16 × MT for cCPN stimulation. Across all participants, the onset of the cSOL EMG suppression was 42 ± 4, 44 ± 3 and 44 ± 3 ms for iPTN, cCPN and iPTN + cCPN conditions, respectively. The inhibition from the combined iPTN and cCPN stimulation was significantly greater compared to the algebraic sum of their separate effects. When conditioning the cSOL H-reflex, the ISI between the test cPTN and the iPTN or cCPN stimulus was 5.4 ± 0.5 and 2.6 ± 0.5, respectively. The combined stimulation induced a significantly greater inhibition compared to their separate effects. These data provide evidence of convergence on common inhibitory interneurons by muscle afferents activated by iPTN and cCPN stimulation during sitting. Since the inhibition elicited by cCPN stimulation is known to be mediated by the disynaptic Ia inhibitory pathway, this suggests that the crossed inhibition of cSOL motoneurones elicited by muscle afferents from the ipsilateral plantarflexor muscles is at least partly mediated by Ia inhibitory interneurons in the contralateral human spinal cord. This is similar to what has been observed in the cat.

Faith Moves Mountains-Mountains Move Faith: Two Opposite Epidemiological Forces in Research on Religion and Health

Research suggests opposite epidemiological forces in religion and health: (1). Faith seems to move mountains in the sense that religion is associated with positive health outcomes. (2). Mountains of bad health seem to move faith. We reflected on these forces in a population of 3000 young Danish twins in which all religiosity measures were associated with severe disease. We believe the reason for this novel finding is that the sample presents as a particularly secular population-based study and that the second epidemiological force has gained the upper hand in this sample. We suggest that all cross-sectional research on religion and health should be interpreted in light of such opposite epidemiological forces potentially diluting each other.

The validated sun exposure questionnaire: association of objective and subjective measures of sun exposure in a Danish population-based sample

BACKGROUND

Few questionnaires used in monitoring sun-related behaviour have been tested for validity.

OBJECTIVES

We established the criteria validity of a questionnaire developed for monitoring population sun-related behaviour.

METHODS

During May-August 2013, 664 Danes wore a personal electronic ultraviolet radiation (UVR) dosimeter for 1 week that measured their outdoor time and dose of erythemal UVR exposure. In the following week, they answered a questionnaire on their sun-related behaviour in the measurement week.

RESULTS

Outdoor time measured by dosimetry correlated strongly with both outdoor time and the developed exposure scale measured in the questionnaire. Exposure measured in standard erythema dose (SED) by dosimetry correlated strongly with the exposure scale. In a linear regression model of UVR (SED) received, 41% of the variation was explained by skin type, age, week of participation and exposure scale, with exposure scale as the main contributor. The weekly sunburn fraction correlated strongly with the number of ambient sun hours (r = 0·73, P < 0·001).

CONCLUSIONS

This criteria-validated questionnaire provides evidence of the exposure that the questionnaire aimed to measure. The evidence provided showed a strong link between the objectively measured behaviour and the behaviour measured by this survey construct. The questionnaire is the first validated tool to measure the UVR exposure in a national population-based sample.

Mutational and phenotypical spectrum of phenylalanine hydroxylase deficiency in Denmark

We describe the genotypes of the complete cohort, from 1967 to 2014, of phenylketonuria (PKU) patients in Denmark, in total 376 patients. A total of 752 independent alleles were investigated. Mutations were identified on 744 PKU alleles (98.9%). In total, 82 different mutations were present in the cohort. The most frequent mutation c.1315+1G>A (IVS12+1G>A) was found on 25.80% of the 744 alleles. Other very frequent mutations were c.1222C>T (p.R408W) (16.93%) and c.1241A>G (p.Y414C) (11.15%). Among the identified mutations, five mutations; c.532G>A (p.E178K), c.730C>T (p.P244S), c.925G>A (p.A309T), c.1228T>A (p.F410I), and c.1199+4A>G (IVS11+4A>G) have not been reported previously. The metabolic phenotypes of PKU are classified into four categories; 'classical PKU', 'moderate PKU', 'mild PKU' and 'mild hyperphenylalaninemia'. In this study, we assigned the phenotypic outcome of three of the five novel mutations and furthermore six not previously classified mutations to one of the four PKU categories.

Monitoring meticillin resistant Staphylococcus aureus and its spread in Copenhagen, Denmark, 2013, through routine whole genome sequencing

Typing of meticillin resistant Staphylococcus aureus (MRSA) by whole genome sequencing (WGS) is performed routinely in Copenhagen since January 2013. We describe the relatedness, based on WGS data and epidemiological data, of 341 MRSA isolates. These comprised all MRSA (n = 300) identified in Copenhagen in the first five months of 2013. Moreover, because MRSA of staphylococcal protein A (spa)-type 304 (t304), sequence type (ST) 6 had been associated with a continuous neonatal ward outbreak in Copenhagen starting in 2011, 41 t304 isolates collected in the city between 2010 and 2012 were also included. Isolates from 2013 found to be of t304, ST6 (n=14) were compared to the 41 earlier isolates. In the study, isolates of clonal complex (CC) 22 were examined in detail, as this CC has been shown to include the hospital-acquired epidemic MRSA (EMRSA-15) clone. Finally, all MRSA ST80 were also further analysed, as representatives of an important community-acquired MRSA in Europe. Overall the analysis identified 85 spa-types and 35 STs from 17 CCs. WGS confirmed the relatedness of epidemiologically linked t304 neonatal outbreak isolates. Several non-outbreak related patients had isolates closely related to the neonatal isolates suggesting unrecognised community chains of transmission and insufficient epidemiological data. Only four CC22 isolates were related to EMRSA-15. No community spread was observed among the 13 ST80 isolates. WGS successfully replaced conventional typing and added information to epidemiological surveillance. Creation of a MRSA database allows clustering of isolates based on single nucleotide polymorphism (SNP) calling and has improved our understanding of MRSA transmission.

Detailed statistical analysis plan for the Danish Palliative Care Trial (DanPaCT)

BACKGROUND

Advanced cancer patients experience considerable symptoms, problems, and needs. Early referral of these patients to specialized palliative care (SPC) could offer improvements. The Danish Palliative Care Trial (DanPaCT) investigates whether patients with metastatic cancer will benefit from being referred to 'early SPC'. DanPaCT is a multicenter, parallel-group, superiority clinical trial with 1:1 randomization. The planned sample size was 300 patients. The primary data collection for DanPaCT is finished. To prevent outcome reporting bias, selective reporting, and data-driven results, we present a detailed statistical analysis plan (SAP) for DanPaCT here.

RESULTS

This SAP provides detailed descriptions of the statistical analyses of the primary and secondary outcomes in DanPaCT. The primary outcome is the change in the patient's 'primary need'. The 'primary need' is a patient-individualised outcome representing the score of the symptom or problem that had the highest intensity out of seven at baseline assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). Secondary outcomes are the seven scales that are represented in the primary outcome, but each scale evaluated individually for all patients, and survival. The detailed description includes chosen significance levels, models for multiple imputations, sensitivity analyses and blinding. In addition, we discuss the patient-individualized primary outcome, blinding, missing data, multiplicity and the risk of bias.

CONCLUSIONS

Only few trials have investigated the effects of SPC. To our knowledge DanPaCT is the first trial to investigate screening based 'early SPC' for patients with metastatic cancer from a broad spectrum of cancer diagnosis.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT01348048 (May 2011).

Central common drive to antagonistic ankle muscles in relation to short-term cocontraction training in nondancers and professional ballet dancers

Optimization of cocontraction of antagonistic muscles around the ankle joint has been shown to involve plastic changes in spinal and cortical neural circuitries. Such changes may explain the ability of elite ballet dancers to maintain a steady balance during various ballet postures. Here we investigated whether short-term cocontraction training in ballet dancers and nondancers leads to changes in the coupling between antagonistic ankle motor units. Eleven ballet dancers and 10 nondancers were recruited for the study. Prior to training, ballet dancers and nondancers showed an equal amount of coherence in the 15- to 35-Hz frequency band and short-term synchronization between antagonistic tibialis anterior and soleus motor units. The ballet dancers tended to be better at maintaining a stable cocontraction of the antagonistic muscles, but this difference was not significant (P = 0.09). Following 27 min of cocontraction training, the nondancers improved their performance significantly, whereas no significant improvement was observed for the ballet dancers. The nondancers showed a significant increase in 15- to 35-Hz coherence following the training, whereas the ballet dancers did not show a significant change. A group of control subjects (n = 4), who performed cocontraction of the antagonistic muscles for an equal amount of time, but without any requirement to improve their performance, showed no change in coherence. We suggest that improved ability to maintain a stable cocontraction around the ankle joint is accompanied by short-term plastic changes in the neural drive to the involved muscles, but that such changes are not necessary for maintained high-level performance.

Chronological age affects the permeation of fentanyl through human skin in vitro

AIM

To study the influence of chronological age on fentanyl permeation through human skin in vitro using static diffusion cells. Elderly individuals are known to be more sensitive to opioids and obtain higher plasma concentrations following dermal application of fentanyl compared to younger individuals. The influence of age - as an isolated pharmacokinetic term - on the absorption of fentanyl has not been previously studied.

METHOD

Human skin from 30 female donors was mounted in static diffusion cells, and samples were collected during 48 h. Donors were divided into three age groups: <30 years of age (n = 6), ≥30 and <60 years of age (n = 18) and ≥60 years of age (n = 6).

RESULTS

The youngest group had a significantly higher mean absorption (3,100 ng/cm(2)) than the two other groups (2,000 and 1,475 ng/cm(2), respectively) and a significant larger AUC (young age group: 9,393 ng; middle and old age groups: 5,922 and 4,050 ng, respectively). Furthermore, the lag time and absorption rate were different between the three groups, with a significantly higher rate in the young participants versus the oldest participants.

CONCLUSION

We demonstrate that fentanyl permeates the skin of young individuals in greater amounts and at a higher absorption rate than in middle-aged and old individuals in vitro.

An abbreviated MLVA identifies Escherichia coli ST131 as the major extended-spectrum β-lactamase-producing lineage in the Copenhagen area

Rapid bacterial typing is a valuable and necessary tool in the prevention and detection of outbreaks. The purpose of this study was to adapt a multilocus variable number of tandem repeats analysis (MLVA) for analysis on a benchtop capillary electrophoresis instrument and compare the modified assay with multilocus sequence typing (MLST) for typing cefpodoxime-resistant Escherichia coli (E. coli). Further, we identified the causative resistance mechanisms and epidemiological type of infection for isolates producing extended-spectrum β-lactamases (ESBLs). A collection of E. coli resistant to cefpodoxime was typed by MLST and a modified MLVA assay using a benchtop capillary electrophoresis instrument. Resistance mechanisms were identified by polymerase chain reaction (PCR) and sequencing. Patient history was examined to establish the epidemiological type of infection for ESBL-producing E. coli. MLVA yielded typing results homologous with MLST and it correctly identified E. coli sequence type (ST) 131 that was accounting for 45 % of all ESBL-producing isolates in the sample collection. The majority (76.7 %) of ESBL-producing isolates was healthcare-related and only 23.3 % of the ESBL-producing isolates were community-onset infections (COI), regardless of the ST. Patients with COI were significantly more often of female gender and younger age compared to healthcare-associated infections (HCAI) and hospital-onset infections (HOI). In conclusion, the modified MLVA is a useful tool for the rapid typing of E. coli and it identified ST131 as the predominating ESBL-producing lineage in Copenhagen. Healthcare-related infections were the predominant infection setting of ESBL-producing E. coli and the demographic characteristics differed between patients with COI and healthcare-related infections.

Twenty weeks of computer-training improves sense of agency in children with spastic cerebral palsy

Children with cerebral palsy (CP) show alteration of perceptual and cognitive abilities in addition to motor and sensory deficits, which may include altered sense of agency. The aim of this study was to evaluate whether 20 weeks of internet-based motor, perceptual and cognitive training enhances the ability of CP children to determine whether they or a computer are responsible for the movement of a visually observed object. 40 CP children (8-16 years) were divided into a training (n:20) and control group (n:20). The training group trained 30 min each day for 20 weeks. The ability of the children to judge whether they themselves or a computer were responsible for moving an object on a computer screen was tested before and after the 20-week period. Furthermore, we included a healthy age-matched group to determine a normal functional level of performance. Our results showed a significantly larger increase in the number of correct subjective reporting for the training group (p<0.001). In accordance with this, the training group was also less fooled by computer-induced movements given by a decreased curvature which indicated a compensatory motor strategy when drawing the line to hit the target following the training than the control group (p=0.018). These findings suggest that sense of agency may be altered, and that training of sense of agency may help to increase the outcome of training programmes in children with CP.

The motor cortex drives the muscles during walking in human subjects

Indirect evidence that the motor cortex and the corticospinal tract contribute to the control of walking in human subjects has been provided in previous studies. In the present study we used coherence analysis of the coupling between EEG and EMG from active leg muscles during human walking to address if activity arising in the motor cortex contributes to the muscle activity during gait. Nine healthy human subjects walked on a treadmill at a speed of 3.5–4 km h(-1). Seven of the subjects in addition walked at a speed of 1 km h(-1). Significant coupling between EEG recordings over the leg motor area and EMG from the anterior tibial muscle was found in the frequency band 24–40 Hz prior to heel strike during the swing phase of walking. This signifies that rhythmic cortical activity in the 24–40 Hz frequency band is transmitted via the corticospinal tract to the active muscles during walking. These findings demonstrate that the motor cortex and corticospinal tract contribute directly to the muscle activity observed in steady-state treadmill walking.

Effects of renal denervation on the NKCC2 cotransporter in the thick ascending limb of the loop of Henle in rats with congestive heart failure

AIM

Congestive heart failure (CHF) is associated with increased renal sympathetic nerve activity and renal sodium retention. Rats with CHF display increased expression of the Na-K-2Cl cotransporter (NKCC2) in the renal medullary thick ascending limb of the loop of Henle (mTAL), and arginine vasopressin (AVP)-stimulated cAMP formation in mTAL segments is increased in rats with CHF. The aim of the study was to investigate the role of RSNA on cAMP formation and NKCC2 expression in mTAL in rats with CHF.

METHODS

Congestive heart failure was induced in male Wistar rats by ligation of the left anterior descending coronary artery. Bilateral surgical renal denervation (DNX) was performed 3 weeks later. Two weeks after DNX, mTAL segments were isolated and stimulated with AVP.

RESULTS

Congestive heart failure rats displayed increased mTAL NKCC2 expression (2.5 ± 0.5 vs. 1 ± 0.2 in Sham rats), which was abolished by DNX. Bilateral denervation decreased basal cAMP levels in unstimulated tubules from CHF rats (CHF: 12.56 ± 7.73 fmol μg(-1) protein vs. DNX-CHF: 7.94 ± 4.33; P < 0.05), as well as from Sham rats (SHAM: 4.70 ± 1.38 vs. DNX-SHAM: 2.36 ± 1.52; P < 0.05). mTAL segments from DNX-CHF and DNX-Sham rats showed decreased AVP (10(-6) M)-stimulated cAMP formation, compared with CHF (CHF: 11.92 ± 4.89 fmol μg(-1) protein vs. DNX-CHF: 4.68 ± 2.47; P < 0.05) and Sham (SHAM: 10.78 ± 5.59 vs. DNX-SHAM: 4.89 ± 2.62; P < 0.05).

CONCLUSION

These results indicate that the renal sympathetic nerves have an effect on NKCC2 expression in the mTAL and might have an effect on cAMP formation in the TAL in CHF.

Fictive locomotion in the adult decerebrate and spinal mouse in vivo

Recently, transgenic mice have been created with mutations affecting the components of the mammalian spinal central pattern generator (CPG) for locomotion; however, it has currently only been possible to evoke fictive locomotion in mice, using neonatal in vitro preparations. Here, we demonstrate that it is possible to evoke fictive locomotion in the adult decerebrate mouse in vivo using l-3,4-dihydroxyphenylalanine methyl ester hydrochloride (l-DOPA) and 5-hydroxytryptophan (5HTP) following injection of the monoaminoxiadase inhibitor Nialamide. We investigate the effects of afferent stimulation and spinalization as well as demonstrate the possibility of simultaneous intracellular recording of rhythmically active motoneurones. Our results demonstrate that several features of the mouse locomotor CPG are similar to those that have been observed in rat, cat, rabbit and monkey suggesting a fairly conserved organisation and allowing for future results in transgenic mice to be extrapolated to existing knowledge of CPG components and circuitry obtained in larger species.

Probe depth matters in dermal microdialysis sampling of benzoic acid after topical application: an ex vivo study in human skin

Microdialysis (MD) in the skin - dermal microdialysis (DMD) - is a unique technique for sampling of topically as well as systemically administered drugs at the site of action, e.g. sampling of dermatological drug concentrations in the dermis. Debate has concerned the existence of a correlation between the depth of the sampling device - the probe - in the dermis and the amount of drug sampled following topical drug administration. This study evaluates the relation between probe depth and drug sampling using dermal DMD sampling ex vivo in human skin. We used superficial (<1 mm), intermediate (1-2 mm) and deep (>2 mm) positioning of the linear MD probe in the dermis of human abdominal skin, followed by topical application of 4 mg/ml of benzoic acid (BA) in skin chambers overlying the probes. Dialysate was sampled every hour for 12 h and analysed for BA content by high-performance liquid chromatography. Probe depth was measured by 20-MHz ultrasound scanning. The area under the time-versus-concentration curve (AUC) describes the drug exposure in the tissue during the experiment and is a relevant parameter to compare for the 3 dermal probe depths investigated. The AUC(0-12) were: superficial probes: 3,335 ± 1,094 μg·h/ml (mean ± SD); intermediate probes: 2,178 ± 1,068 μg·h/ml, and deep probes: 1,159 ± 306 μg·h/ml. AUC(0-12) sampled by the superficial probes was significantly higher than that of samples from the intermediate and deeply positioned probes (p value <0.05). There was a significant inverse correlation between probe depth and AUC(0-12) sampled by the same probe (p value <0.001, r(2) value = 0.5). The mean extrapolated lag-times (±SD) for the superficial probes were 0.8 ± 0.1 h, for the intermediate probes 1.7 ± 0.5 h, and for the deep probes 2.7 ± 0.5 h, which were all significantly different from each other (p value <0.05). In conclusion, this paper demonstrates that there is an inverse relationship between the depth of the probe in the dermis and the amount of drug sampled following topical penetration ex vivo. The result is of relevance to the in vivo situation, and it can be predicted that the differences in sampling at different probe depths will have a more significant impact in the beginning of a study or in studies of short duration. Based on this study it can be recommended that studies of topical drug penetration using DMD sampling should include measurements of probe depth and that efforts should be made to minimize probe depth variability.

Intrinsic properties of lumbar motor neurones in the adult G127insTGGG superoxide dismutase-1 mutant mouse in vivo: evidence for increased persistent inward currents

AIM

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by a preferential loss of motor neurones. Previous publications using in vitro neonatal preparations suggest an increased excitability of motor neurones in various superoxide dismutase-1 (SOD1) mutant mice models of ALS which may contribute to excitotoxicity of the motor neurones.

METHODS

Using intracellular recording, we tested this hypothesis in vivo in the adult presymptomatic G127insTGGG (G127X) SOD1 mutant mouse model of ALS.

RESULTS

At resting membrane potentials the basic intrinsic properties of lumbar motor neurones in the adult presymptomatic G127X mutant are not significantly different from those of wild type. However, at more depolarized membrane potentials, motor neurones in the G127X SOD1 mutants can sustain higher frequency firing, showing less spike frequency adaption (SFA) and with persistent inward currents (PICs) being activated at lower firing frequencies and being more pronounced.

CONCLUSION

We demonstrated that, in vivo, at resting membrane potential, spinal motor neurones of the adult G127X mice do not show an increased excitability. However, when depolarized they show evidence of an increased PIC and less SFA which may contribute to excitotoxicity of these neurones as the disease progresses.

Cerebral activation is correlated to regional atrophy of the spinal cord and functional motor disability in spinal cord injured individuals

Recovery of function following lesions in the nervous system requires adaptive changes in surviving circuitries. Here we investigate whether changes in cerebral activation are correlated to spinal cord atrophy and recovery of functionality in individuals with incomplete spinal cord injury (SCI). 19 chronic SCI individuals and 7 age-comparable controls underwent functional magnetic resonance imaging (fMRI) while performing rhythmic dorsiflexion of the ankle. A significant negative correlation was found between the activation in the ipsilateral motor (M1) and bilateral premotor cortex (PMC) on one hand and the functional ability of the SCI participants measured by the clinical motor score on the other. There was no significant correlation between activation in any other cerebral area and the motor score. Activation in ipsilateral somatosensory cortex (S1), M1 and PMC was negatively correlated to the width of the spinal cord in the left-right direction, where the corticospinal tract is located, but not in the antero-posterior direction. There was a tendency for a negative correlation between cerebral activation in ipsilateral S1, M1 and PMC and the amplitude of motor evoked potentials in the tibialis anterior muscle elicited by transcranial magnetic stimulation, but this did not reach statistical significance. There was no correlation between motor score or spinal cord dimensions and the volume of the cortical motor areas. The observations show that lesion of descending tracts in the lateral part of the spinal cord results in increased activation in ipsilateral motor and sensory areas, which may help to compensate for the functional deficit following SCI.

Independent spinal cord atrophy measures correlate to motor and sensory deficits in individuals with spinal cord injury

STUDY DESIGN

Cross-sectional descriptive analysis of magnetic resonance imaging (MRI) and clinical outcome.

OBJECTIVES

The aim of this study was to present anatomically consistent and independent spinal cord atrophy measures based on standard MRI material and analyze their specific relations to sensory and motor outcome in individuals with chronic incomplete spinal cord injury (SCI).

SETTING

Danish study on human SCI.

METHODS

We included 19 individuals with chronic incomplete SCI and 16 healthy controls. Participants underwent MRI and a neurological examination including sensory testing for light touch and pinprick, and muscle strength. Antero-posterior width (APW), left-right width (LRW) and cross-sectional spinal cord area (SCA) were extracted from MRI at the spinal level of C2. The angular variation of the spinal cord radius over the full circle was also extracted and compared with the clinical scores.

RESULTS

The motor score was correlated to LRW and the sensory scores were correlated to APW. The scores correlated also well with decreases in spinal cord radius in oblique angles in coherent and non-overlapping sectors for the sensory and motor qualities respectively.

CONCLUSION

APW and LRW can be used to assess sensory and motor function independently. The finding is corresponding well with the respective locations of the main sensory and motor pathways.

Microdialysis sampling for investigations of bioavailability and bioequivalence of topically administered drugs: current state and future perspectives

Microdialysis (MD) in the skin is a unique technique for in vivo sampling of topically as well as systemically administered drugs at the site of action, e.g. sampling the unbound tissue concentrations in the dermis and subcutaneous tissue. MD as a research method has undergone significant development, improvement and validation during the last decade and has proved to be a versatile, safe and valuable tool for pharmacokinetic and pharmacodynamic studies. This review gives an overview of the current state and future perspectives of dermal MD sampling. Methodological issues such as choice of instrumentation, calibration and experimental procedures are discussed along with the analytical considerations necessary for successful sampling. Clinical MD studies in the skin are reviewed with emphasis on pharmacokinetic studies of topically applied drugs with or without impairment of skin barrier function by skin disease or barrier perturbation. A comparison between MD and other tissue sampling techniques reveals the advantages and limitations of the method. Subsequently, an in-depth discussion of the application of MD for the evaluation of bioavailability and bioequivalence of topical formulations is concluded by the current regulatory point of view. The future perspective includes further expansion and validation of the use of MD in the experimental and clinical setting as well as in the optimization of the method for regulatory purposes, i.e. the commercialization of bioequivalent, generic drug products.

Intrinsic properties of mouse lumbar motoneurons revealed by intracellular recording in vivo

We have developed an in vivo model for intracellular recording in the adult anesthetized mouse using sharp microelectrode electrodes as a basis for investigations of motoneuron properties in transgenic mouse strains. We demonstrate that it is possible to record postsynaptic potentials underlying identified circuits in the spinal cord. Forty-one motoneurons with antidromic spike potentials (>50 mV) from the sciatic nerve were investigated. We recorded the intrinsic properties of the neurons, including input resistance (mean: 2.4 +/- 1.2 MOmega), rheobase (mean: 7.1 +/- 5.9 nA), and the duration of the afterhyperpolarization (AHP; mean: 55.3 +/- 14 ms). We also measured the minimum firing frequencies (F(min), mean 23.5 +/- 5.7 SD Hz), the maximum firing frequencies (F(max); >300 Hz) and the slope of the current-frequency relationship (f-I slope) with increasing amounts of current injected (mean: 13 +/- 5.7 Hz/nA). Signs of activation of persistent inward currents (PICs) were seen, such as accelerations of firing frequency or jumps in the membrane potential with increasing amounts of injected current. It is likely that the particular anesthetic regime with a mixture of Hypnorm and midazolam is essential for the possibility to evoke PICs. The data demonstrate that mouse spinal motoneurons share many of the same properties that have been demonstrated previously for cat, rat, and human motoneurons. The shorter AHP duration, steeper f-I slopes, and higher F(min) and F(max) than those in rats, cats, and humans are likely to be tailored to the characteristics of the mouse muscle contraction properties.

The 2008 ICOH Workshop on Skin Notation

BACKGROUND

On 29 March 2008 the International Commission on Occupational Health (ICOH) Scientific Committee on Occupational and Environmental Dermatoses organized a Skin Notation Workshop hosted by the 11th International Percutaneous Penetration Perspectives Conference (La Grande Motte, France). Skin notation (S) was chosen as a topic for discussion because this is the only example of existing regulation in the field of dermal risk assessment. The issue was discussed in a previous workshop held in Siena, Italy in 2006 with the objective of focussing on the problems related to S, the different assignment criteria and the attempts to improve the S system made by various international and governmental agencies. A position paper was subsequently published.

OBJECTIVES

The workshop in France was a continuation of this activity with the aim of evaluating how the different strategies can improve S.

METHODS AND DISCUSSION

The Workshop was divided into two sessions. The first was dedicated to lectures focused on different aspects of S. In the second session participants discussed key issues with the aim of exploring the actions needed to improve international S. systems.

Absorption of iron from slow-release and rapidly-disintegrating tablets - a comparative study in normal subjects, blood donors and subjects with iron deficiency anaemia

The absorption of iron from slow-release and rapidly-disintegrating ferrous sulphate tablets has been compared using a double radioiron isotope technique. The studies were performed in 15 normal subjects, 20 blood donors and 10 patients with iron deficiency anaemia. The preparations containing 100 mg of ferrous iron were given twice daily on alternate days for 10 days. The absorption differed significantly between the three groups of subjects, being highest in the anaemic patients and lowest in the normal subjects. In all groups, significantly more iron was absorbed from the slow-release tablets compared to the rapidly-disintegrating tablets. The mean absorption ratios were 1.3 in both normal subjects and blood donors. In patients with iron deficiency anaemia the ratio was 1.4.

Losartan decreases vasopressin-mediated cAMP accumulation in the thick ascending limb of the loop of Henle in rats with congestive heart failure

INTRODUCTION

Vasopressin (AVP) stimulates sodium reabsorption and Na,K,2Cl-cotransporter (NKCC2) protein level in the thick ascending limb (TAL) of Henle's loop in rats. Rats with congestive heart failure (CHF) have increased protein level of NKCC2, which can be normalized by angiotensin II receptor type-1 (AT(1)) blockade with losartan.

AIM

In this study, we investigated whether CHF rats displayed changes in AVP stimulated cAMP formation in the TAL and examined the role of AT(1) receptor blockade on this system.

METHOD

CHF was induced by ligation of the left anterior descending coronary artery (LAD). SHAM-operated rats were used as controls. Half of the rats were treated with losartan (10 mg kg day(-1) i.p.).

RESULTS

CHF rats were characterized by increased left ventricular end diastolic pressure. Measurement of cAMP in isolated outer medullary TAL showed that both basal and AVP (10(-6) m) stimulated cAMP levels were significantly increased in CHF rats (25.52 +/- 4.49 pmol cAMP microg(-1) protein, P < 0.05) compared to Sham rats (8.13 +/- 1.14 pmol cAMP microg(-1) protein), P < 0.05). Losartan significantly reduced the basal level of cAMP in CHF rats (CHF: 12.56 +/- 1.93 fmol microg(-1) protein vs. Los-CHF: 7.49 +/- 1.08, P < 0.05), but not in Sham rats (SHAM: 4.66 +/- 0.59 vs. Los-SHAM: 4.75 +/- 0.71). AVP-mediated cAMP accumulation was absent in both groups treated with losartan (Los-SHAM: 4.75 +/- 0.71 and Los-CHF: 7.49 +/- 1.08).

CONCLUSION

The results indicate that the increased NKCC2 protein level in the mTAL from CHF rats is associated with increased cAMP accumulation in this segment. Furthermore, the finding that AT(1) receptor blockade prevents AVP-mediated cAMP accumulation in both SHAM and CHF rats suggests an interaction between angiotensin II and AVP in regulation of mTAL Na reabsorption.

Reduced reciprocal inhibition is seen only in spastic limbs in patients with neurolathyrism

If reduced reciprocal inhibition plays a causal role in the pathophysiology of spasticity as has been suggested in several studies, the inhibition is expected to be impaired in spastic, but not in normal muscles. Patients with neurolathyrism offer a possibility of testing this prediction since the spastic symptoms in these patients are restricted to the lower extremities only. Three patients with neurolathyrism were tested. Their data were compared with 15 age-matched healthy subjects. All patients showed signs of spasticity in the legs. Two patients had normal voluntary muscle force in the lower extremities and one had decreased force. No clinical abnormalities were found in the upper extremities. Reciprocal inhibition between ankle dorsiflexor and plantarflexor muscles was absent in all patients, whereas the inhibition between wrist extensor and flexor muscles was present and of normal size and latency. These findings are consistent with the hypothesis that reduced reciprocal inhibition plays a causal role in the pathophysiology of spasticity.

Evaluation of transcranial magnetic stimulation for investigating transmission in descending motor tracts in the rat

In the rat, non-invasive transcranial magnetic stimulation (TMS) has shown promise for evaluation of transmission through the spinal cord before and after repair strategies, but it is still unclear which pathways are activated by TMS. The aim of the present study was therefore to identify these pathways and to analyse the effect of TMS on spinal neurons. In 19 rats, TMS evoked responses bilaterally in forelimb (biceps brachii; BB) and hindlimb muscles (tibialis anterior). The latency and amplitude of these motor-evoked responses (MEPs) were highly variable and depended strongly on the coil position and the stimulation intensity. The most frequently observed latencies for the BB MEPs could be divided into three groups: 3-6 ms, 8-12 ms and 14-18 ms. Lesions in the dorsal columns, which destroyed the corticospinal tract at C2 and C5, significantly depressed MEPs in the mid- and high-latency ranges, but not those in the low-latency range. Lesions in the dorsolateral funiculus, which interrupted the rubrospinal tract, had no effect on MEPs in any of the latency ranges. By contrast, bilateral lesion of the reticulospinal tract and other ventro-laterally located descending pathways abolished all responses. Intracellular recordings from 54 cervical motoneurons in five rats revealed that TMS evoked excitatory postsynaptic potentials (EPSPs) at latencies that corresponded well with those of the BB MEPs. The short-latency EPSPs had rise times of around 1 ms, suggesting that they were mediated by a monosynaptic pathway. EPSPs with longer latencies had considerably longer rise times, which indicated conduction through polysynaptic pathways. Selective electrical stimulation of the pyramidal tract in the brainstem was performed in seven rats, where intracellular recordings from 70 motoneurons revealed that the earliest EPSPs and MEPs evoked by TMS were not mediated by the corticospinal tract, but by other descending motor pathways. Together, these results showed that in the rat TMS activates several descending pathways that converge on common spinal interneurons and motoneurons. Our observations confirm that the corticospinal tract has weak (and indirect) projections to cervical spinal motoneurons.

The spinal pathophysiology of spasticity--from a basic science point of view

Spasticity is a term, which was introduced to describe the velocity-sensitive increased resistance of a limb to manipulation in subjects with lesions of descending motor pathways. This distinguishes spasticity from the changes in passive muscle properties, which are often seen in these patients, but are not velocity-sensitive. Increased excitability of the stretch reflex is thus a central component of the definition of spasticity. This review describes changes in cellular properties and transmission in a number of spinal reflex pathways, which may explain the increased stretch reflex excitability. The review focuses mainly on results derived from the use of non-invasive electrophysiological techniques, which have been developed during the past 20-30 years to investigate spinal neuronal networks in human subjects, but work from animal models is also considered. The reflex hyperexcitability develops over several months following the primary lesion and involves adaptation in the spinal neuronal circuitries caudal to the lesion. In animal models, changes in cellular properties (such as 'plateau potentials') have been reported, but the relevance of these changes to human spasticity has not been clarified. In humans, numerous studies have suggested that reduction of spinal inhibitory mechanisms (in particular that of disynaptic reciprocal inhibition) is involved. The inter-subject variability of these mechanisms and the lack of objective quantitative measures of spasticity have impeded disclosure of a clear causal relationship between the alterations in the inhibitory mechanisms and the stretch reflex hyperexcitability. Techniques which make such a quantitative measure possible as well as longitudinal studies where development of reflex excitability and changes in the inhibitory mechanisms are followed over time are in great demand.

Spinal control of locomotion--from cat to man

For a large number of vertebrate species it is now indisputable that spinal networks have the capability of generating the basic locomotor rhythm. The aim of this review is to summarize the evidence for spinal pattern generators in cats and primates, including man and its interaction with sensory signals from the limbs. For all species the sensory feed-back from the moving limb is very important to achieve effective locomotor behaviour by adapting to the environment and compensating for unexpected postural disturbances. Sensory regulation of stepping can occur via reflex pathways to motoneurones (by-passing the locomotor rhythm generators) or by acting on the spinal locomotor networks themselves. The sensory feed-back serves to control the timing of the different phases in the step cycle, to shape the pattern of muscle activity, to contribute to the excitatory drive of the motoneurones and to the long-term adaptation of the locomotor activity. In this review we discuss the spinal locomotor circuits and the sensory feed-back in animals (mainly the cat) and human subjects. Special emphasis is given to work that has been of importance for the development of new rehabilitation paradigms following spinal cord injury.

A review of the toxicity of Melaleuca alternifolia (tea tree) oil

The essential oil of Melaleuca alternifolia, also known as tea tree or melaleuca oil, is widely available and has been investigated as an alternative antimicrobial, anti-inflammatory and anti-cancer agent. While these properties are increasingly well characterised, relatively limited data are available on the safety and toxicity of the oil. Anecdotal evidence from almost 80 years of use suggests that the topical use of the oil is relatively safe, and that adverse events are minor, self-limiting and occasional. Published data indicate that TTO is toxic if ingested in higher doses and can also cause skin irritation at higher concentrations. Allergic reactions to TTO occur in predisposed individuals and may be due to the various oxidation products that are formed by exposure of the oil to light and/or air. Adverse reactions may be minimised by avoiding ingestion, applying only diluted oil topically and using oil that has been stored correctly. Data from individual components suggest that TTO has the potential to be developmentally toxic if ingested at higher doses, however, TTO and its components are not genotoxic. The limited ecotoxicity data available indicate that TTO is toxic to some insect species but more studies are required.

Spasticity-assessment: a review

STUDY DESIGN

Review of the literature on the validity and reliability of assessment of spasticity and spasms.

OBJECTIVES

Evaluate the most frequently used methods for assessment of spasticity and spasms, with particular focus on individuals with spinal cord lesions.

SETTING

Clinic for Spinal Cord Injuries, Rigshospitalet, University Hospital of Copenhagen, and Department of Medical Physiology, University of Copenhagen, Denmark.

METHODS

The assessment methods are grouped into clinical, biomechanical and electrophysiological, and the correlation between these is evaluated.

RESULTS

Clinical methods: For assessment of spasticity, the Ashworth and the modified Ashworth scales are commonly used. They provide a semiquantitative measure of the resistance to passive movement, but have limited interrater reliability. Guidelines for the testing procedures should be adhered to. Spasm frequency scales seem not to have been tested for reliability. Biomechanical methods such as isokinetic dynamometers are of value when an objective quantitative measure of the resistance to passive movement is necessary. They play a minor role in the daily clinical evaluation of spasticity. Electrophysiological methods: These techniques have provided valuable insight to the pathophysiological mechanisms involved in spasticity, but none of these techniques provide an easy and reliable assessment of spasticity for use in the daily clinic.

CONCLUSION

A combination of electrophysiological and biomechanical techniques shows some promise for a full characterization of the spastic syndrome. There is a need of simple instruments, which provide a reliable quantitative measure with a low interrater variability.

Vitamin B12 and vitamin B6 supplementation is needed among adults with phenylketonuria (PKU)

Phenylketonuria (PKU) is caused by an autosomal recessive deficiency of the enzyme phelnylalanine hydroxylase leading to a failure to convert phenylalanine to tyrosine. To avoid irreversible neurological damage because of increased phenylalanine, treatment is instituted rapidly after birth. We examined 31 adult PKU patients living on a less protein-restricted diet. Theoretically, these PKU patients had an increased risk of developing vitamin B(12) and B(6) deficiency because of a limited intake of animal products. Besides laboratory tests (n = 31) we obtained clinical information (n = 30) and detailed information on food consumption (n = 28). Three-quarters of the patients had early biochemical signs of vitamin B(12) deficiency. In spite of a normal folate status, 9 (29%) had a plasma homocysteine above 12 micromol/L. In accord with these findings, the food questionnaires indicated that 11 (39%) patients received less than the recommended daily vitamin B(12), and 20 (71%) received less vitamin B(6) than recommended. A significant association was found between reduced vitamin B(12) intake and both reduced serum cobalamins (p = 0.04) and reduced serum transcobalamin saturation (p = 0.03). Eleven patients took a vitamin pill daily, and these patients had a significantly lower plasma homocysteine compared to the rest. The present study suggests that adult PKU patients were at increased risk of developing vitamin B(12) deficiency, and their intake of vitamin B(6) was below the recommended daily intake. In conclusion PKU patients need continuing dietary guidance throughout adult life, and considering the risks, costs and potential benefits, daily vitamin supplementation seems justified in these patients.

Organization of common synaptic drive to motoneurones during fictive locomotion in the spinal cat

The basic locomotor rhythm in the cat is generated by a neuronal network in the spinal cord. The exact organization of this network and its drive to the spinal motoneurones is unknown. The purpose of the present study was to use time (cumulant density) and frequency domain (coherence) analysis to examine the organization of the last order drive to motoneurones during fictive locomotion (evoked by application of nialamide and dihydroxyphenylalanine (DOPA)) in the spinal cat. In all cats, narrow central synchronization peaks (half-width < 3 ms) were observed in cumulants estimated between electroneurograms (ENGs) of close synergists, but not between nerves belonging to muscles acting on different joints or to antagonistic muscles. Coherence was not observed at frequencies above 100 Hz and was mainly observed between synergists. Intracellular recording was obtained from a population of 70 lumbar motoneurones. Significant short-term synchronization was observed between the individual intracellular recordings and the ENGs recorded from nerves of the same pool and of close synergists. Recordings from 34 pairs of motoneurones (10 pairs belonged to the same motor pool, 11 pairs to close synergists and 13 pairs to antagonistic pools) failed to reveal any short-lasting synchronization. These data demonstrate that short-term synchronization during fictive locomotion is relatively weak and is restricted to close synergists. In addition, coherence analysis failed to identify any specific rhythmic component in the locomotor drive that could be associated with this synchronization. These results resemble findings obtained during human treadmill walking and imply that the spinal interneurones participating in the generation of the locomotor rhythm are themselves weakly synchronized. The restricted synchronization within the locomotor drive to motoneuronal pools may be a feature of the locomotor generating networks that is related to the ability of these networks to produce highly adaptive patterns of muscle activity during locomotion.

The effect of penile vibratory stimulation on male fertility potential, spasticity and neurogenic detrusor overactivity in spinal cord lesioned individuals

PURPOSE

Present the possibility for treatment of male infertility, spasticity, and neurogenic detrusor overactivity in spinal cord lesioned (SCL) individuals with penile vibratory stimulation (PVS).

METHOD

Obtaining reflex-ejaculation by PVS, by using a vibrator developed for this purpose. The stimulation was performed with a vibrating disc of hard plastic placed against the frenulum of the penis (amplitude > or = 2.5 mm). The vibration continued until antegrade ejaculation or for a maximum of 3 minutes followed by a pause of 1 minute before the cycle was repeated, maximally 4 times.

RESULTS

>80% SCL men are able to obtain ejaculation with PVS. Pregnancy rates obtained with home PVS and intra-vaginal insemination was 22-62% (4 studies), and with PVS or electroejaculation and intrauterine insemination/in-vitro fertilization/intracytoplasmatic sperm injection 39-64% (9 studies). PVS was demonstrated to decrease spasticity significantly when measured by the modified Ashworth scale. In addition, a decrease of the number of spontaneous EMG events which probably indicate spasms was observed. Increase in bladder capacity at leakpoint following 4 weeks of frequent ejaculation with PVS treatment was likewise demonstrated.

CONCLUSION

PVS has proved its importance for SCL male fertility, in the years to come its place in treatment of spasticity and neurogenic detrusor overactivity has to be established.

Reduction of common synaptic drive to ankle dorsiflexor motoneurons during walking in patients with spinal cord lesion

It is possible to obtain information about the synaptic drive to motoneurons during walking by analyzing motor-unit coupling in the time and frequency domains. The purpose of the present study was to compare motor-unit coupling during walking in healthy subjects and patients with incomplete spinal cord lesion to obtain evidence of differences in the motoneuronal drive that result from the lesion. Such information is of importance for development of new strategies for gait restoration. Twenty patients with incomplete spinal cord lesion (SCL) participated in the study. Control experiments were performed in 11 healthy subjects. In all healthy subjects, short-term synchronization was evident in the discharge of tibialis anterior (TA) motor units during the swing phase of treadmill walking. This was identified from the presence of a narrow central peak in cumulant densities constructed from paired EMG recordings and from the presence of significant coherence between these signals in the 10- to 20-Hz band. Such indicators of short-term synchrony were either absent or very small in the patient group. The relationship between the amount of short-term synchrony and the magnitude of the 10- to 20-Hz coherence in the patients is discussed in relation to gait ability. It is suggested that supraspinal drive to the spinal cord is responsible for short-term synchrony and coherence in the 10- to 20-Hz frequency band during walking in healthy subjects. Absence or reduction of these features may serve as physiological markers of impaired supraspinal control of gait in SCL patients. Such markers could have diagnostic and prognostic value in relation to the recovery of locomotion in patients with central motor lesions.