Stimulation parameters for motor evoked potentials during intraoperative spinal cord monitoring. A systematic review

OBJECTIVE

The aim of this systematic review was to find the optimal stimulation parameters for muscle recorded transcranial electrical stimulation motor evoked potential (mTc-MEP) and D-wave monitoring during spinal cord monitoring.

METHODS

A PRISMA systematic search in Medline and EMBASE and a QUADAS-2 quality evaluation was performed to identify studies that compared stimulation parameters consisting of stimulation location, number of pulses, pulse duration, interstimulus interval, double train (DTS) or recurrent train stimulation (RTS) and intertrain interval (ITI) for performing mTc-MEP and D-wave monitoring. Only studies that used total intravenous anaesthesia (TIVA) were included.

RESULTS

Ten studies that compared stimulation parameters for performing mTc-MEP monitoring (stimulation location n = 4, number of pulses n = 2, pulse duration n = 1, interstimulus interval n = 4, DTS n = 1, RTS n = 2, ITI n = 2) were included. No studies compared stimulation parameters (stimulation location and pulse duration) for performing D-wave monitoring.

CONCLUSIONS

Few studies examined the optimal stimulation parameters for monitoring mTc-MEPs and no studies were included for D-wave monitoring. There is a need for prospective research to investigate the optimal stimulation parameters for mTc-MEP with the use of TIVA and D-wave monitoring.

SIGNIFICANCE

For mTc-MEP monitoring, a table is provided in which the recommended stimulation parameters are stated.

Feasibility and optimal choice of stimulation parameters for supramaximal stimulation of motor evoked potentials

PURPOSE

The aim was to investigate the feasibility and optimal stimulation parameters for supramaximal stimulation of muscle recorded transcranial electrical stimulation motor evoked potentials (mTc-MEP).

METHODS

Forty-seven consecutive patients that underwent scoliosis surgery were included. First, the feasibility of supramaximal stimulation was assessed for two settings (setting 1: pulse duration 0.075ms, interstimulus interval (ISI) 1.5ms; setting 2: pulse duration 0.300ms, ISI 3ms). Thereafter, three mTc-MEP parameters were considered for both settings; (1) elicitability, (2) amplitude, and (3) if supramaximal stimulation was achieved with ≥ 20 V below maximum output. Finally, ISIs (1ms-4ms) were optimized for setting 1.

RESULTS

Nine patients (19.15%) were excluded. Of the remaining patients, supramaximal stimulation was achieved in all patients for setting 1, and in 26 (68.42%) for setting 2. In one patient, mTc-MEPs were elicitable in more muscles for setting (1) Amplitudes were not significantly different. Stimulation voltage could be increased ≥ 20 V in all 38 patients for setting 1 and in 10 (38.46%) for setting (2) Optimal ISI's differed widely.

CONCLUSION

We recommend using setting 1 when monitoring mTc-MEPs with supramaximal stimulation, after which an individualized ISI optimization can be performed. Moreover, when using supramaximal stimulation, short ISI's (i.e. 1ms or 1.5ms) can be the optimal ISI for obtaining the highest mTc-MEP amplitude.

Neonatal Brain Temperature Monitoring Based on Broadband Near-Infrared Spectroscopy

We present here the initial development of a novel algorithm based on broadband near-infrared spectroscopy (bNIRS) data to estimate the changes in brain temperature (BT) in neonates. We first explored the validity of the methodology on a simple numerical phantom and reported good agreements between the theoretical and retrieved values of BT and hemodynamic parameters changes, which are the parameters usually targeted by bNIRS. However, we noted an underestimation of the absolute values of temperature and haemoglobins' concentration changes when large variations of tissue saturation were induced, probably due to a crosstalk between the species in this specific case. We then tested this methodology on data acquired on 2 piglets during a protocol that induces seizures. We showed that despite a decrease in rectal temperature (RT) over time (-0.1048 °C 1.5 h after seizure induction, 95% CI: -0.1035 to -0.1061 °C), BT was raising (0.3122 °C 1.5 h after seizure induction, 95% CI: 0.3207 to 0.3237 °C). We also noted that the piglet displaying the largest decrease in RT also displays the highest increase in BT, which could be a marker of the severity of the seizure induced brain injury. These initial results are encouraging and show that having access to the changes in BT non-invasively could help to better understand the impact of BT on injury severity and to improve the current cooling methodologies in the neonatal neurocritical care following neonatal encephalopathy.

Measuring saccades in patients with Niemann-Pick type C: A comparison between video-oculography and a novel eye tracking test based on continuous psychophysics

Introduction

Vertical supranuclear gaze palsy is a key feature of Niemann-Pick type C (NP-C) and is commonly quantified using video-oculography (VOG). VOG requires sitting still for long times and performing specific tasks, thus it can be challenging or impossible for patients severely affected by movement disorders or cognitive impairment. To overcome this limitation, we measure saccades of NP-C patients using a fast eye tracking test based on continuous psychophysics and compare it to VOG.

Methods

Saccades of six NP-C patients and six age-matched controls were assessed using VOG and Standardized Oculomotor and Neuro-ophthalmic Disorders Assessment (SONDA). In SONDA, participants continuously track a semi-randomly moving dot on a computer screen while their gaze is being tracked. For both assessments, saccades were quantified using four conventional measures: amplitude, gain, latency, and peak velocity. Furthermore, SONDA's continuous measures were quantified with several novel spatio-temporal properties.

Results

In the NP-C patients, both methods revealed reduced amplitude, gain, peak velocity, and increased latency of vertical saccades compared to horizontal saccades and compared to healthy controls. Effect sizes obtained with SONDA were overall larger than those for VOG. SONDA's spatio-temporal properties showed similar trends.

Conclusion

SONDA reveals a deterioration of vertical saccades in NP-C patients that is consistent with VOG. SONDA's measures based on continuous psychophysics are consistent with traditional saccadic parameters and can potentially provide complementary information. SONDA shows larger effect sizes than VOG, suggesting that it provides robust and clinically relevant outcomes with a more intuitive task and shorter testing time.

POS1395 NEUROFILAMENT LIGHT CHAIN, AN EARLY BIOMARKER FOR POLYNEUROPATHY IN HEREDITARY ATTR AMYLOIDOSIS

Background

Serum neurofilament light chain (sNfL) is a sensitive marker for polyneuropathy (PNP) in hereditary transthyretin-related (ATTRv) amyloidosis patients and correlates with the severity of polyneuropathy [1-4]. We hypothesized that sNfL may diagnose neuronal damage in patients with hATTR amyloidosis before the onset of symptoms and before PNP can be detected by electromyography (EMG) examination.

Objectives

To establish the course of sNfL in three different groups: 1. persistently asymptomatic variant carriers (with and without detected amyloid), 2. ATTRv amyloidosis patients with PNP on treatment, 3. variant carriers who develop PNP.

Methods

sNfL levels were assessed longitudinally in asymptomatic variant carriers (with and without detectable amyloid), ATTRv amyloidosis patients with PNP on treatment (either a transthyretin (TTR) stabilizer or patisiran, an RNA interference therapeutic), and variant carriers who developed PNP. PNP was established by EMG examination. The single-molecule array (Simoa) assay was used to assess sNfL levels.

Results

sNfL levels significantly increased over 1 year in 20 persistently asymptomatic carriers (p<0.001), with the strongest increase in variant carriers (n=8) with detectable amyloid in the subcutaneous abdominal fat tissue. In 21 symptomatic ATTRv amyloidosis patient with PNP on treatment with a TTR stabilizer, sNfL levels remained stable over 1 year. In 24 patients treated with patisiran, sNfL levels significantly decreased after 1 year of treatment (p=0.01). In 8 out of 9 variant carriers who developed PNP a rise in the sNfL level could be observed before the onset of symptoms and establishment of PNP by EMG examination (Figure 1).

Figure 1.

Conclusion

sNfL is a marker for early neuronal damage since a rise in sNfL level occurs before abnormalities can be detected by EMG examination. Our data support the use of sNfL in monitoring disease progression, screening asymptomatic variant carriers and monitoring of treatment effect.

References

[1]Louwsma et al. Amyloid 2021;28(1):50-55

[2]Maia et al. Amyloid 2020;27(2):97-102

[3]Kapoor et al. J Perpher nerv syst 2019;24:314-319

[4]Ticau et al. Neurology 2021;96:e412-e422

Disclosure of Interests

Anne Floor Brunger: None declared, Milou Berends: None declared, Johan Bijzet: None declared, Paul van der Zwaag: None declared, Bart-Jan Kroesen: None declared, Charlotte Teunissen: None declared, Sjors in ‘t Veld: None declared, Gea Drost: None declared, Fiete Lange: None declared, Reinold Gans: None declared, Bouke Hazenberg Consultant of: Alnylam and Pfizer, Hans L.A. Nienhuis Consultant of: Alnylam and Pfizer

Upper Trapezius Muscle Tonicity, Assessed by Palpation, Relates to Change in Tissue Oxygenation and Structure as Measured by Time-Domain Near Infrared Spectroscopy

Palpation is a diagnostic tool widely used by manual therapists despite its disputed reliability and validity. Previous studies have usually focused on the detection of myofascial trigger points (MTrPs), i.e., the points within muscles thought to have undergone molecular composition, oxygenation and structural changes, altering their tonicity. Time-domain near-infrared spectroscopy (TD-NIRS) could provide new insights into soft tissue oxygenation and structure, in order to objectively assess the validity and reliability of palpation. This pilot study aims at (1) assessing the ability of TD-NIRS to detect a difference between palpably normal and hypertonic upper trapezius (UT) muscles, and (2) to estimate the reproducibility of the TD-NIRS measurement on UT muscles. TD-NIRS measurements were performed on 4 points of the UT muscles in 18 healthy participants (10F, mean age: 27.6 years), after a physical examination by a student osteopath to locate these points and identify the most and least hypertonic. From TD-NIRS, the most hypertonic points had a higher concentration in deoxy- ([HHb]) (0.887 ± 0.253 μM, p < 0.001) and total haemoglobin ([HbT]) (1.447 ± 0.772 μM, p < 0.001), a lower tissue oxygen saturation (StO2) (-0.575 ± 0.286%, p < 0.001), and a greater scattering amplitude factor (AF) (0.2238 ± 0.1343 cm-1, p = 0.001) than the least hypertonic points. Moreover, the intraclass correlation coefficient one-way random-effects model (ICC (1,1)) calculated for each TD-NIRS parameter and for each point revealed an excellent reliability of the measurement (Mean ± SD, 0.9253 ± 0.0678). These initial results, showing that changes in TD-NIRS parameters correlate with changes in muscle tonicity as assessed by palpation, are encouraging and show that TD-NIRS could help to further assess the validity of palpation as a diagnostic tool in manual therapy.

[Update on collaborative autopsy-based research in German pathology, neuropathology, and forensic medicine]

BACKGROUND

Autopsies are a valuable tool for understanding disease, including COVID-19.

MATERIALS AND METHODS

The German Registry of COVID-19 Autopsies (DeRegCOVID), established in April 2020, serves as the electronic backbone of the National Autopsy Network (NATON), launched in early 2022 following DEFEAT PANDEMIcs.

RESULTS

The NATON consortium's interconnected, collaborative autopsy research is enabled by an unprecedented collaboration of 138 individuals at more than 35 German university and non-university autopsy centers through which pathology, neuropathology, and forensic medicine autopsy data including data on biomaterials are collected in DeRegCOVID and tissue-based research and methods development are conducted. More than 145 publications have now emerged from participating autopsy centers, highlighting various basic science and clinical aspects of COVID-19, such as thromboembolic events, organ tropism, SARS-CoV‑2 detection methods, and infectivity of SARS-CoV-2 at autopsy.

CONCLUSIONS

Participating centers have demonstrated the high value of autopsy and autopsy-derived data and biomaterials to modern medicine. The planned long-term continuation and further development of the registry and network, as well as the open and participatory design, will allow the involvement of all interested partners.

The influence of depth of anesthesia and blood pressure on muscle recorded motor evoked potentials in spinal surgery. A prospective observational study protocol

For high-risk spinal surgeries, intraoperative neurophysiological monitoring (IONM) is used to detect and prevent intraoperative neurological injury. The motor tracts are monitored by recording and analyzing muscle transcranial electrical stimulation motor evoked potentials (mTc-MEPs). A mTc-MEP amplitude decrease of 50–80% is the most common warning criterion for possible neurological injury. However, these warning criteria often result in false positive warnings. False positives may be caused by inadequate depth of anesthesia and blood pressure on mTc-MEP amplitudes. The aim of this paper is to validate the study protocol in which the goal is to investigate the effects of depth of anesthesia (part 1) and blood pressure (part 2) on mTc-MEPs. Per part, 25 patients will be included. In order to investigate the effects of depth of anesthesia, a processed electroencephalogram (pEEG) monitor will be used. At pEEG values of 30, 40 and 50, mTc-MEP measurements will be performed. To examine the effect of blood pressure on mTc-MEPs the mean arterial pressure will be elevated from 60 to 100 mmHg during which mTc-MEP measurements will be performed. We hypothesize that by understanding the effects of depth of anesthesia and blood pressure on mTc-MEPs, the mTc-MEP monitoring can be interpreted more reliably. This may contribute to fewer false positive warnings. By performing this study after induction and prior to incision, this protocol provides a unique opportunity to study the effects of depths of anesthesia and blood pressure on mTc-MEPs alone with as little confounders as possible.

Trial registration number NL7772.

Caregiver burden and health-related quality of life in idiopathic dystonia patients under botulinum toxin treatment: a cross-sectional study

Dystonia is a chronic movement disorder that is associated with a reduction in health-related quality of life (HR-QoL) and restriction of activities of daily living. Botulinum neurotoxin (BT) improves disease-specific HR-QoL by reducing abnormal movements, postures, and pain. We examined the burden of the corresponding primary caregiver as a potential important factor for disease management and HR-QoL of dystonia patients under treatment with BT. 114 patients with focal, segmental, or generalized dystonia were recruited, together with 93 corresponding caregivers, whose burden was investigated using the Caregiver Burden Inventory. In addition, all participants were assessed for cognitive impairment, depression, anxiety, alexithymia, and HR-QoL. Only a small proportion of caregivers suffered from caregiver burden. Despite BT therapy, patients’ HR-QoL was decreased compared to the age-matched general German population. Psychological symptoms, notably anxiety, and depression correlated significantly with reduced HR-QoL. Our data imply that caregiver burden emerged to be an issue in subgroups of dystonia patients. Furthermore, HR-QoL of dystonia patients is reduced even under optimized BT treatment in a specialized center.

Estimating the effective number of breeders from single parr samples for conservation monitoring of wild populations of Atlantic salmon Salmo salar

This study assesses whether the effective number of breeders (N_b ) can be estimated using a time and cost-effective protocol using genetic sibship reconstruction from a single sample of young-of-the-year (YOY) for the purposes of Atlantic salmon Salmo salar population monitoring. N_b was estimated for 10 consecutive reproductive seasons for S. salar in the River Nivelle, a small population located at the rear-edge of the species distribution area in France, chronically under its conservation limit and subjected to anthropogenic and environmental changes. Subsampling of real and simulated data showed that accurate estimates of N_b can be obtained from YOY genotypes, collected at moderate random sampling intensity, achievable using routine juvenile electrofishing protocols. Spatial bias and time elapsed since spawning were found to affect estimates, which must be accounted for in sampling designs. N_b estimated in autumn for S. salar in the River Nivelle was low and variable across years from 23 (95% C.I. 14-41) to 75 (53-101) and was not statistically correlated with the estimated number of returning adults, but it was positively correlated with the estimated number of YOY at age 9 months. N_b was found to be lower for intermediate levels of redd aggregation, suggesting that the strength of the competition between males to access females affects reproductive success variance depending on redd spatial configuration. Thus, environmental factors such as habitat availability and quality for spawning and YOY development predominate over demographic ones (number of returning adults) in driving long-term population viability for S. salar in the River Nivelle. This study showcases N_b as an integrated parameter, encompassing demographic and ecological information about a reproductive event, relevant to the assessment of both short-term effects of management practices and long-term population conservation status.

199 Efficient Knock-out of Ovine β-Lactoglobulin (BLG) Gene and Knock-in of Recombinant Human Factor IX (rhFIX) Under BLG Native Regulatory Sequences in Somatic Cells and Zygotes Using TALEN Nuclease

Site-specific genetic engineering is a valuable tool for pharmaceutical research and development of biomedical models. Despite engineered nucleases allow targeted gene edition in a rather simple fashion; few reports are available so far on specific gene knock-in (KI) combined with engineered nucleases in domestic species. Here, we evaluated the possibility of inducing specific KI of cDNAs coding for proteins of pharmaceutical interest under the control of milk native promoter sequences, taking advantage of the TALEN system, both in ovine somatic cells and in zygotes. We designed 2 TALENs, targeting exons 1 and 5 of ovine β-lactoglobulin gene (BLG), respectively, and a homologous recombination vector (pHR), carrying recombinant human factor IX (rhFIX) flanked by homology arms contiguous to the TALEN target sites. In an initial set of experiments, 5 × 105 to 1 × 106 ovine fibroblasts were transfected with 1 μg of each TALEN mRNA, with or without 50 ng μL−1 pHR. The feasibility of inducing knock-out (KO) was confirmed by Cel1 assay. The deletion of the genomic region between TALEN target sites and the occurrence of HR in cell lysates were assessed by PCR. Also, 576 individual colonies were picked up and analyzed by PCR. The deletion of the region between TALEN target sites was achieved with 7.8% efficiency (45/576). The incidence of HR in cells was 0.5% (3/576), as detected by PCR. In order to evaluate the system in zygotes, laparoscopic AI was performed on synchronized and superovulated ewes. Zygotes were recovered 16 h after AI and cytoplasmically injected with (1) 5 ng μL−1 TALEN mix (2.5 ng μL−1 oaBLG T1.1 + 2.5 ng μL−1 oaBLG T5.1) (5TM); (2) 5 ng μL−1 TALEN mix + 25 ng μL−1 pHR-hFIX plasmid (5TM+25pRH); or (3) 15 ng μL−1 TALEN mix (7.5 ng μL−1 oaBLG T1.1 + 7.5 ng μL−1 oaBLG T5.1) + 50 ng μL−1 pHR-hFIX (15TM+50pRH). A non-injected control (NIC) was also included. Embryo analysis was conducted on whole-genome amplified DNA from blastocysts, followed by PCR and sequencing. Non-parametric Fisher test was applied to detect significant differences among treatments. Although blastocyst rates for NIC and 5TM did not statistically differ, 5TM+25pRH and 15TM+50pRH groups resulted in lower blastocysts rates than the NIC [P < 0.05; 13/17 (76%), 6/15 (40%), 4/15 (26%) and 2/14 (14%) for NIC, 5TM, 5TM+25pRH and 15TM+50pRH respectively]. It was possible to detect the PCR product compatible with deletion of the entire region among TALEN target sites in 6/6 blastocysts (100%) from the group 5TM, 3/4 blastocysts (75%) from the group 5TM+25pRH and 2/2 (100%) blastocysts from the group 15TM+50pRH. HR was detected in 1/2 (50%) blastocysts injected with 15TM+50pRH and in 1/4 (25%) blastocysts injected with 5TM+25pRH, by PCR and sequencing of the PCR products. Our results indicate that TALEN combined with homologous recombination constitutes a powerful platform for the production of proteins of pharmaceutical interest under native regulatory sequences in the milk of genetically modified animals.

Assessing Tn5 and Sleeping Beauty for transpositional transgenesis by cytoplasmic injection into bovine and ovine zygotes

Transgenic domestic animals represent an alternative to bioreactors for large-scale production of biopharmaceuticals and could also provide more accurate biomedical models than rodents. However, their generation remains inefficient. Recently, DNA transposons allowed improved transgenesis efficiencies in mice and pigs. In this work, Tn5 and Sleeping Beauty (SB) transposon systems were evaluated for transgenesis by simple cytoplasmic injection in livestock zygotes. In the case of Tn5, the transposome complex of transposon nucleic acid and Tn5 protein was injected. In the case of SB, the supercoiled plasmids encoding a transposon and the SB transposase were co-injected. In vitro produced bovine zygotes were used to establish the cytoplasmic injection conditions. The in vitro cultured blastocysts were evaluated for reporter gene expression and genotyped. Subsequently, both transposon systems were injected in seasonally available ovine zygotes, employing transposons carrying the recombinant human factor IX driven by the beta-lactoglobulin promoter. The Tn5 approach did not result in transgenic lambs. In contrast, the Sleeping Beauty injection resulted in 2 lambs (29%) carrying the transgene. Both animals exhibited cellular mosaicism of the transgene. The extraembryonic tissues (placenta or umbilical cord) of three additional animals were also transgenic. These results show that transpositional transgenesis by cytoplasmic injection of SB transposon components can be applied for the production of transgenic lambs of pharmaceutical interest.

Long-term evaluation of intraoperative neurophysiological monitoring-assisted tethered cord surgery

PURPOSE

Patients with tethered spinal cord have been investigated for short-term effects after tethered spinal cord surgery in the past. However, little is known about the long-term effects in this patient group. In this retrospective, longitudinal, observational study, a patient sample of a previous report of 65 patients was reassessed to observe the long-term effects of intraoperative neurophysiological monitoring-assisted tethered cord surgery.

METHODS

With the use of patient charts and a survey, patients were scored on four domains: (1) neurological deficits, (2) urological deficits, (3) pain symptoms, and (4) orthopedic deficits. Measurements were performed at four moments in time: (1) preoperatively, (2) postoperatively, (3) follow-up 1 (4.6 years), and (4) follow-up 2 (11.2 years). Besides this, a subgroup analysis and a quality of life questionnaire were performed.

RESULTS

When observing the symptom domains in the long-term, the pain domain appeared to improve most postoperatively after which it remained stable over time. The neurological and urological domains showed a stable, slightly decreasing trend in the long-term follow-up. The orthopedic domain showed a significant increase of the number of patients with scoliosis during the long-term follow-up.

CONCLUSIONS

Lasting effects of stability in the neurological, urological, and pain domains were observed. Close monitoring during follow-up might contribute to early recognition of progressive scoliosis, in spite of detethering, in a risk group defined by females who underwent tethered cord surgery at or under the age of 12 years old with either lipomyelomeningocele, split cord malformation, or myelomeningocele. Detethering does not appear to protect these patients against progressive scoliosis.

Toward a clinical application of ex situ boron neutron capture therapy for lung tumors at the RA-3 reactor in Argentina

PURPOSE

Many types of lung tumors have a very poor prognosis due to their spread in the whole organ volume. The fact that boron neutron capture therapy (BNCT) would allow for selective targeting of all the nodules regardless of their position, prompted a preclinical feasibility study of ex situ BNCT at the thermal neutron facility of RA-3 reactor in the province of Buenos Aires, Argentina. (l)-4p-dihydroxy-borylphenylalanine fructose complex (BPA-F) biodistribution studies in an adult sheep model and computational dosimetry for a human explanted lung were performed to evaluate the feasibility and the therapeutic potential of ex situ BNCT.

METHODS

Two kinds of boron biodistribution studies were carried out in the healthy sheep: a set of pharmacokinetic studies without lung excision, and a set that consisted of evaluation of boron concentration in the explanted and perfused lung. In order to assess the feasibility of the clinical application of ex situ BNCT at RA-3, a case of multiple lung metastases was analyzed. A detailed computational representation of the geometry of the lung was built based on a real collapsed human lung. Dosimetric calculations and dose limiting considerations were based on the experimental results from the adult sheep, and on the most suitable information published in the literature. In addition, a workable treatment plan was considered to assess the clinical application in a realistic scenario.

RESULTS

Concentration-time profiles for the normal sheep showed that the boron kinetics in blood, lung, and skin would adequately represent the boron behavior and absolute uptake expected in human tissues. Results strongly suggest that the distribution of the boron compound is spatially homogeneous in the lung. A constant lung-to-blood ratio of 1.3 ± 0.1 was observed from 80 min after the end of BPA-F infusion. The fact that this ratio remains constant during time would allow the blood boron concentration to be used as a surrogate and indirect quantification of the estimated value in the explanted healthy lung. The proposed preclinical animal model allowed for the study of the explanted lung. As expected, the boron concentration values fell as a result of the application of the preservation protocol required to preserve the lung function. The distribution of the boron concentration retention factor was obtained for healthy lung, with a mean value of 0.46 ± 0.14 consistent with that reported for metastatic colon carcinoma model in rat perfused lung. Considering the human lung model and suitable tumor control probability for lung cancer, a promising average fraction of controlled lesions higher than 85% was obtained even for a low tumor-to-normal boron concentration ratio of 2.

CONCLUSIONS

This work reports for the first time data supporting the validity of the ovine model as an adequate human surrogate in terms of boron kinetics and uptake in clinically relevant tissues. Collectively, the results and analysis presented would strongly suggest that ex situ whole lung BNCT irradiation is a feasible and highly promising technique that could greatly contribute to the treatment of metastatic lung disease in those patients without extrapulmonary spread, increasing not only the expected overall survival but also the resulting quality of life.

Electroencephalographic Findings in Posthypoxic Myoclonus

The physical examination findings of early posthypoxic myoclonus (PHM) are associated with poor prognosis. Recent findings indicate that patients with multifocal PHM, assumed to have a cortical origin, have a comparable outcome to resuscitated patients without PHM. Generalized PHM, assumed to have a subcortical myoclonus origin, is still associated with a bad clinical outcome. It is not known whether the electroencephalographic (EEG) findings differ between the multifocal and generalized myoclonus groups nor is the clinical significance clearly defined. Forty-three patients with PHM were retrospectively derived from an EEG database. Patients were categorized as having multifocal (i), generalized (ii), or undetermined (iii) PHM. Outcome was expressed in cerebral performance category scores. The EEG background was categorized into isoelectric (I), low voltage (II), burst suppression (III), status epilepticus (SE; IV), diffuse slowing (V), and mild encephalopathic or normal (VI). 17 patients had generalized PHM and 23 had multifocal PHM (3 undetermined). The EEG showed more SE in generalized compared to multifocal PHM (64% vs 13%, P< .001). Diffuse slowing was more often present in multifocal PHM (52% vs 17%, P < .05). Early-onset myoclonus occurred significantly more often in generalized PHM, and early generalized PHM was invariantly associated with poor outcome. In conclusion, patients with generalized PHM showed more SE. These EEG findings might be either subcortical corollaries or primarily cortical phenomena. Our retrospective results conflict with currently used clinical criteria for myoclonus classification, and we suggest that more refined difference may be needed for accurate assessment of PHM. To better understand PHM, prospective research with standardized clinical assessment and quantitative EEG analysis is needed.

355 COMPARISON OF Tn5 AND SLEEPING BEAUTY SYSTEMS IN BOVINE EMBRYOS AND IN OVINE OFFSPRING

Current techniques for the production of transgenic domestic animals remain inefficient. Only recently, DNA transposons resulted in improved efficiencies for mouse and pig transgenesis. In this work, we evaluated Tn5 and Sleeping Beauty systems for transgenesis in bovine and ovine species. First, both transposon systems were assessed in vitro in bovine embryos employing transposons carrying fluorescent reporter genes. In vitro-produced bovine zygotes were microinjected with either 1) a complex of Tn5:egfp transposon (20 ng μL–1) (protein: transgene with mosaic ends recognised by Tn5, in Mg+2 free medium), or 2) two plasmids carrying Sleeping Beauty 100X (pSB100X, 5 ng μL–1) and pT2/Venus transposon (10 ng μL–1). In vitro results for Tn5 transgenesis in bovine showed that blastocysts, Day 4 egfp embryos and egfp blastocysts rates for the group injected with Tn5:egfp did not differ from the group injected with the egfp transposon alone (73/145, 50%; 86/145, 59%; and 65/145, 45% v. 65/129, 50%; 87/129, 67%; and 57/129, 44%, respectively). For SB transgenesis, blastocysts, D4 Venus embryos, and Venus blastocysts rates did not differ between co-injection of pSB100X and pT2/Venus or injection with pT2/Venus alone (46/99, 46.5%; 64/99, 64.6%; and 33/99, 33.3% v. 41/83, 49.4%; 52/83, 62.7%; and 26/83, 31.3%, respectively). However, Venus intensity in blastocysts was markedly higher for the group co-injected with pSB100X and pT2/Venus respective to pT2/Venus alone. Both systems were assessed in vivo for the production of transgenic lambs employing a functional transposon (hrFIX, recombinant human factor IX driven by a Beta-lactoglobulin promoter). Laparoscopic artificial insemination of donor sheep was performed, and presumptive zygotes were flushed from the oviducts. The microinjections were done identically as described for the bovine embryos. A total of 24 presumptive zygotes were recovered and injected with the Tn5:hrFIX complex. Then, 21 zygotes were transferred to 5 synchronized ewes; one pregnancy of siblings was obtained, and one animal was born. Genomic DNA from skin, placenta, and blood was genotyped by PCR, but the hrFIX gene could not be detected. For the SB approach, 64 presumptive zygotes were recovered from 4 superovulated ewes, microinjected with the SB plasmids, and 21 of them were transferred to 7 oestrous synchronized recipients. The remaining zygotes were cultured in vitro and blastocysts (n = 7) were vitrified. Currently, 3 donor ewes are pregnant, one with siblings (4 total fetuses). Deliveries are expected by the end of August of this year. Our results indicate that both Tn5 and SB systems are capable of resulting in the production of transgene expressing embryos, and the presence of the transposases does not affect embryo viability. However, phenotyping of blastocyst stages does not seem to be predictive for stable transgene integration. The in vivo results will help to better address the suitability of Tn5 and SB approaches for the production of transgenic sheep.

[Low level laser therapy in inflammatory and infectious oral diseases]

PURPOSE

Low Level Laser Therapy (LLLT) is an increasingly studied technique. The authors of a meta-analysis published in 2012 had already confirmed the effectiveness of LLLT for radio-induced mucitis. Our purpose was to check its indication for similar pathologies.

MATERIAL AND METHODS

The articles were selected with the PubMed engine. The selected terms were "Low Level Laser Therapy", "oral surgery", "oral infection", "oral inflammation", "oral mucosal lesions", "oral mucosal disease", "stomatitis", "aphtous", "Herpes", "oral lichen planus", and "oral ulceration". The analysis was made on the following criteria: assessment criteria, methodological quality, and bias. We estimated the level of proof according to Sackett's modified score.

RESULTS

Six articles were selected. Two focused on the effectiveness of LLLT for Herpes simplex virus 1 oral symptoms. Two focused on the effectiveness of LLLT for oral lichen planus. One focused on the effectiveness of LLLT for recurrent aphthous stomatitis. The last one focused on the usefulness of LLLT to control stomatitis pain in the hand-foot-and-mouth disease.

CONCLUSION

All the selected studies were assessed with a Sackett's score of IV. No study presented the required quality standards to recommend the treatment of LLLT for the selected indications.

[Infectious cellulitis of the face complicating injection for esthetic nasolabial sulcus by hyaluronic acid: report of seven cases]

We report a case series of seven patients with bacterial cellulitis of the face complicating a filler injection for cosmetic reason, treated in a university hospital from 2005 to 2012. There were seven women aged 34 to 57 years. Two patients had a deep collection requiring surgical excision combined with antibiotics. Five patients were treated with antibiotics only. In two cases the bacteria was found streptococcus A and in one case Staphylococcus aureus. One patient required hospitalization in an intensive care unit. Only patients who needed surgical treatment showed moderate aesthetic sequelae.

[Techniques of anastomoses issue from vascular surgery and apply to maxillofacial microsurgery]

Vascular surgeons use an anastomosis technique that has proven its efficiency for a long time. This technique consists in an anastomosis with spatulated ended vessels designed with opposite obliquity. This anastomosis is closed by a continuous suture. Authors expose the results of this technique applied to microvascular surgery in facial reconstruction.

[Management of plexiform neurofibroma isolated in childhood: four patients]

Plexiform neurofibroma is a rare and benign tumor often associated with type 1 neurofibromatosis (NF1) or Von Recklinghausen's disease. Present in one third of cases of NF1, there are isolated forms where the diagnosis should remain a diagnosis of exclusion. We report four cases of isolated plexiform neurofibromas found in children from topographies and we discuss the pretherapeutic assessment, the surgical management and the long-term follow-up.

Plerixafor with and without chemotherapy in poor mobilizers: results from the German compassionate use program

The CXCR4-inhibitor plerixafor mobilizes hematopoietic stem cells amplifying the effects of granulocyte-CSF (G-CSF). Before approval plerixafor was used in a compassionate use program (CUP) for patients who failed a previous mobilization. In the German CUP 60 patients from 23 centers (median age 56.5 years (2-75)) were given 240 μg/kg plerixafor SC 9-11 h before apheresis. A total of 78.3% (47/60) received G-CSF for 4 days before plerixafor administration; 76.6% of those (36/47) yielded at least 2.0 × 10(6) CD34(+) cells/μL. The median cell yield was 3.35 × 10(6) CD34+ cells/kg (0-29.53). Nine patients received plerixafor alone or with G-CSF for less than 4 days mobilizing a median of 3.30 × 10(6) CD34+ cells/kg (1.6-5.6). There was no significant difference between G-CSF application for 4 days and for a shorter period of time (P=0.157). A total of 47 patients received plerixafor plus G-CSF combined with chemotherapy yielding a median of 3.28 × 10(6) CD34+ cells/kg (0-24.79). In all, 40 of 60 patients (66.7%) proceeded to transplantation, and achieved a timely and stable engraftment. Side effects were rare and manageable. In conclusion, mobilization with plerixafor in poor mobilizers is safe and results in a sufficient stem cell harvest in the majority of patients.

STUDIES ON THE BLOOD VESSELS IN THE MEMBRANES OF CHICK EMBRYOS : PART III. ANATOMY AND PHYSIOLOGY OF THE BLOOD VESSELS AT DIFFERENT AGES

On the basis of the anatomical studies presented the following inferences or conclusions are drawn. 1. In the course of development there appear in the vascular membranes of chick embryos arterial vessels of all calibers, namely, capillaries, small arteries with 2 or 3 cell layers, and large arteries formed of endothelium, longitudinal and circular layers of muscle and adventitia. 2. In none of the stages are elastic fibers developed. Only in the most central portion of the umbilical artery, in that portion namely which is to be regarded as belonging to the embryo, are elastic fibers discoverable. 3. The structure of capillaries is histologically the same at all stages. The small arteries of embryos 10 days old resemble histologically those of 18. At no stage of development are appearances of degeneration nor of fat to be found in arteries. When the physiological results of our investigations are compared with the anatomical ones the following comments may be made. In respect to Paragraph 1 of the anatomical results we may remark that when we study the different forms of the wall of arterial vessels the most delicate vessels consisting of single cells exhibit the greatest irritability. Those which are built of 3 to 4 muscle layers are less irritable. Stouter vessels appearing for the first time at 10 days of incubation require stronger stimuli to bring about the same reaction. In respect to Paragraph 2 of the anatomical results we may make this comment. The absence of elastic fibers in all arteries of the embryonic membranes throughout the period of their development is important in defining a physiological property of the larger vessels. The medium and larger vessels, beginning with the 4th day of incubation, contract differently from normal adult human arteries. In the contracted state they appear in cross section not as small replicas of larger circular structures, but take on a new form. During the course of contraction they become flat and appear band-like as would a garden hose when it is compressed by a weight. In examining a vessel so contracted one sees on rotating the vessel either a broad side or a narrow one. It is for this reason that such arteries appear alternately narrow as a line or broad as a band. It is not until the narrow artery is elevated with a hook that its uniform band-like nature becomes evident. The absence of elastic tissue, the presence of which in all probability is mainly responsible for the usual shape of arteries on cross section, permits one to see how the phenomenon which has been described may come about. Concerning Paragraph 3 of the anatomical conclusions we have this to say. According to the histological investigation a stage of degeneration is wanting in the blood vessels of the embryonic membrane in a sense in which one is accustomed to see such changes in other blood vessel systems during the course of life. On the day of hatching the constituent cells and fibers of the arteries of all calibers are anatomically the same as in their early development. These vessels do not die as the result of aging: The nutrient fluid ceases to flow because of contraction of the umbilical vessels. The blood vessels die in complete possession of their physiological irritability and anatomical integrity. The unaltered irritability of blood vessels of the same caliber at all ages is consonant with their unaltered anatomical structure.

STUDIES ON THE BLOOD VESSELS IN THE MEMBRANES OF CHICK EMBRYOS : PART II. REACTIONS OF THE BLOOD VESSELS IN THE VASCULAR MEMBRANES

A comparison of the effect of stimulation upon the arterial subdivisions shows that these differ in irritability. The capillaries are most irritable, then come the small arterial branches, and last the main stems of arteries, these being the least irritable. The non-innervated blood vessels of the vascular membranes exhibit therefore the behavior described by G. Ricker in the case of those which have a nervous apparatus. We have demonstrated accordingly similar properties in vessels which are not innervated as in those which are. Certain differences exist however. The action of adrenalin on the vessels of the vascular membrane is inconstant and certain other substances are wholly ineffective. Ricker's experiments have advanced knowledge on the regularity of the vascular reactions and have paved the way for these experiments of ours. The result of our experiments with vessels free of nerves suggests that a reexamination may be fruitful of the mechanism which obtains in innervated vessels. There can be no doubt that nerves play a rôle in the behavior of vessels; it appears now to be necessary to define more accurately precisely what this is.

STUDIES ON THE BLOOD VESSELS IN THE MEMBRANES OF CHICK EMBRYOS : PART IV. MODIFICATION OF IRRITABILITY OF THE BLOOD VESSELS

When faradic stimulation was undertaken of vessels irrigated with Ringer's solution, which alternately contained and was free from carbon dioxide, it was observed that the reaction was far less when the solution contained carbon dioxide. A reversal of the effect could be obtained many times. It appears, therefore, that when Ringer's solution contained carbon dioxide in the concentration described, the irritability of the vessels to electrical stimuli decreased, although carbon dioxide by itself and in the absence of the application of the stimuli, appeared to be void of effect upon the vessels. The rare, divergent results were traced to technical errors. We attempted to discover whether the observed decrease in irritability of the vessels might not be due to the absence of oxygen. For this purpose we irrigated the vessels with Ringer's solution alternately containing nitrogen and oxygen. When nitrogen caused any change this was due to an influence on the rate of the heart and not on the irritability or reactivity of the arteries. In whatever way we tried we were unable to bring about a change in reactivity of the arteries by creating a condition of oxygen lack independently of a change in the rate of the heart beat. We attempted to study also the effect of other acids beside carbon dioxide on the changed reactivity of the arteries. Irrigation with various concentrations of lactic acid was without result. We also employed solutions buffered with potassium and sodium phosphate. When the irrigation was undertaken with these solutions having a pH range varying from 7.7 to 5.9 we observed neither a direct action nor one which modified the preparation in such a way as to change its susceptibility to faradic stimulation. Important investigations have been published recently by Atzler and Lehmann (2) on the direct influence of the hydrogen ion concentration on the behavior of blood vessels. Hammett and Zoll believed that, as the result of their experiments in which they attempted to bring about stimulation with solutions of concentrated carbon dioxide, they were able to exclude the possibility of action due to acid alone and therefore ascribed to carbon dioxide a specific effect. In our own experiments the method of irrigation does not permit an inference whether, or how far, an acid effect plays a rôle in the carbon dioxide experiments. For beside the question of hydrogen ion concentration and of buffering, the question of the penetration of substances from the surface to the contractile elements of the wall of the vessels requires to be considered. Carbon dioxide has an ability, beyond that of all other substances, to penetrate through tissues (3). It may be owing to this property that we could influence the reactivity of the blood vessels with it and it alone. This possibility must be further investigated. In these experiments, however, it was our object to show only that it was possible to influence the irritability of blood vessels experimentally. The conclusion is justified by our experiments that carbon dioxide in small concentrations reduces the threshold of irritability for electrical stimuli of the blood vessels of the embryonic membrane.

STUDIES ON THE BLOOD VESSELS IN THE MEMBRANES OF CHICK EMBRYOS : PART I. ABSENCE OF NERVES IN THE VASCULAR MEMBRANE

The agreement of physiological experiment with anatomical findings justifies our conclusion: the blood vessels of the vascular membrane of chick embryos do not contain nerves.