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.