Erector spinae plane block vs. peri-articular injection for pain control after arthroscopic shoulder surgery: a randomised controlled trial.

Interscalene brachial plexus block is the standard regional analgesic technique for shoulder surgery. Given its adverse effects, alternative techniques have been explored. Reports suggest that the erector spinae plane block may potentially provide effective analgesia following shoulder surgery. However, its analgesic efficacy for shoulder surgery compared with placebo or local anaesthetic infiltration has never been established. We conducted a randomised controlled trial to compare the analgesic efficacy of pre-operative T2 erector spinae plane block with peri-articular infiltration at the end of surgery. Sixty-two patients undergoing arthroscopic shoulder repair were randomly assigned to receive active erector spinae plane block with saline peri-articular injection (n = 31) or active peri-articular injection with saline erector spinae plane block (n = 31) in a blinded double-dummy design. Primary outcome was resting pain score in recovery. Secondary outcomes included pain scores with movement; opioid use; patient satisfaction; adverse effects in hospital; and outcomes at 24 h and 1 month. There was no difference in pain scores in recovery, with a median difference (95%CI) of 0.6 (-1.9-3.1), p = 0.65. Median postoperative oral morphine equivalent utilisation was significantly higher in the erector spinae plane group (21 mg vs. 12 mg; p = 0.028). Itching was observed in 10% of patients who received erector spinae plane block and there was no difference in the incidence of significant nausea and vomiting. Patient satisfaction scores, and pain scores and opioid use at 24 h were similar. At 1 month, six (peri-articular injection) and eight (erector spinae plane block) patients reported persistent pain. Erector spinae plane block was not superior to peri-articular injection for arthroscopic shoulder surgery.

The analgesic efficacy of pre-operative bilateral erector spinae plane (ESP) blocks in patients having ventral hernia repair.

Laparoscopic ventral hernia repair is an operation associated with significant postoperative pain, and regional anaesthetic techniques are of potential benefit. The erector spinae plane (ESP) block performed at the level of the T5 transverse process has recently been described for thoracic surgery, and we hypothesised that performing the ESP block at a lower vertebral level would provide effective abdominal analgesia. We performed pre-operative bilateral ESP blocks with 20-30 ml ropivacaine 0.5% at the level of the T7 transverse process in four patients undergoing laparoscopic ventral hernia repair. Median (range) 24-h opioid consumption was 18.7 mg (0.0-43.0 mg) oral morphine. The highest and lowest median (range) pain scores in the first 24 h were 3.5 (3.0-5.0) and 2.5 (0.0-3.0) on an 11-point numerical rating scale. We also performed the block in a fresh cadaver and assessed the extent of injectate spread using computerised tomography. There was radiographic evidence of spread extending cranially to the upper thoracic levels and caudally as far as the L2-L3 transverse processes. We conclude that the ESP block is a promising regional anaesthetic technique for laparoscopic ventral hernia repair and other abdominal surgery when performed at the level of the T7 transverse process. Its advantages are the ability to block both supra-umbilical and infra-umbilical dermatomes with a single-level injection and its relative simplicity.

Stable eusociality via maternal manipulation when resistance is costless.

In many eusocial species, queens use pheromones to influence offspring to express worker phenotypes. Although evidence suggests that queen pheromones are honest signals of the queen's reproductive health, here I show that queen's honest signalling can result from ancestral maternal manipulation. I develop a mathematical model to study the coevolution of maternal manipulation, offspring resistance to manipulation and maternal resource allocation. I assume that (i) maternal manipulation causes offspring to be workers against offspring's interests; (ii) offspring can resist at no direct cost, as is thought to be the case with pheromonal manipulation; and (iii) the mother chooses how much resource to allocate to fertility and maternal care. In the coevolution of these traits, I find that maternal care decreases, thereby increasing the benefit that offspring obtain from help, which in the long run eliminates selection for resistance. Consequently, ancestral maternal manipulation yields stable eusociality despite costless resistance. Additionally, ancestral manipulation in the long run becomes honest signalling that induces offspring to help. These results indicate that both eusociality and its commonly associated queen honest signalling can be likely to originate from ancestral manipulation.

Isotopic discrimination of stable isotopes of nitrogen (δ15N) and carbon (δ13C) in a host-specific holocephalan tapeworm.

During the past decade, parasites have been considered important components of their ecosystems since they can modify food-web structures and functioning. One constraint to the inclusion of parasites in food-web models is the scarcity of available information on their feeding habits and host-parasite relationships. The stable isotope approach is suggested as a useful methodology to determine the trophic position and feeding habits of parasites. However, the isotopic approach is limited by the lack of information on the isotopic discrimination (ID) values of parasites, which is pivotal to avoiding the biased interpretation of isotopic results. In the present study we aimed to provide the first ID values of δ(15)N and δ(13)C between the gyrocotylidean tapeworm Gyrocotyle urna and its definitive host, the holocephalan Chimaera monstrosa. We also test the effect of host body size (body length and body mass) and sex of the host on the ID values. Finally, we illustrate how the trophic relationships of the fish host C. monstrosa and the tapeworm G. urna could vary relative to ID values. Similar to other studies with parasites, the ID values of the parasite-host system were negative for both isotopic values of N (Δδ(15)N = - 3.33 ± 0.63‰) and C (Δδ(13)C = - 1.32 ± 0.65‰), independent of the sex and size of the host. By comparing the specific ID obtained here with ID from other studies, we illustrate the importance of using specific ID in parasite-host systems to avoid potential errors in the interpretation of the results when surrogate values from similar systems or organisms are used.

Automatic cell counting in vivo in the larval nervous system of Drosophila.

Identification and counting of cells is necessary to test biological hypotheses, for instance of nervous system formation, disease, degeneration, injury and regeneration, but manual counting is time consuming, tedious, and subject to bias. The fruit fly Drosophila is a widely used model organism to analyse gene function, and most research is carried out in the intact animal or in whole organs, rather than in cell culture. Inferences on gene function require that cell counts are known from these sample types. Image processing and pattern recognition techniques are appropriate tools to automate cell counting. However, counting cells in Drosophila is a complex task: variations in immunohistochemical markers and developmental stages result in images of very different properties, rendering it challenging to identify true cells. Here, we present a technique for counting automatically larval glial cells in three dimensions, from confocal microscopy serial optical sections. Local outlier thresholding and domes are combined to find the cells. Shape descriptors extracted from a data set are used to characterize cells and avoid oversegmentation. Morphological operators are employed to divide cells that could otherwise be missed. The method is accurate and very fast, and treats all samples equally and objectively, rendering all data comparable across specimens. Our method is also applicable to identify cells labelled with other nuclear markers and in sections of mouse tissues.

The erector spinae plane block for obstetric analgesia: a case series of a novel technique.

The management of pain during labour is central to obstetric anaesthetic practice. While epidural analgesia has long been considered the gold standard for intrapartum analgesia, neuraxial techniques can be challenging to perform, are contra-indicated in circumstances such as coagulopathy. The erector spinae plane block is an interfascial plane block that has generated interest because of a needle tip position away from the neuraxis. This has the potential to mitigate the risks of nerve injury and epidural haematoma formation. The mechanism of action is linked to both paravertebral and epidural distribution of local anaesthetic, providing both somatic and visceral analgesia, with potential utility in obstetric settings. Four women in active labour received either unilateral or bilateral erector spinae plane blocks. All experienced a reduction in pain, ranging from 3 to 6 points measured on a 10-point numerical rating scale. The duration of analgesia ranged from 60 to 120 min. In this report, we discuss potential for using the erector spinae plane block in the management of obstetric pain.

Erector spinae plane block: A cadaver study to determine its mechanism of action. / Bloqueo del plano del músculo erector espinal: estudio anatómico-cadavérico para determinar su mecanismo de acción.

INTRODUCTION: The erector spinae plane (ESP) block is a novel technique for the treatment of acute and chronic pain. Its mechanism and site of action has not yet been explained properly. OBJECTIVES: In order to explain the mechanism of action of the ESP block, injections were performed with methylene blue to simulate the local anaesthetics and to determine its distribution from the anterior side of the thorax. To find an aperture or channel through which the local anaesthetic passes from posterior to anterior through the muscular and bone structures. MATERIALS AND METHODS: Four spinal columns of fresh cryopreserved corpses were used. A total of 9 ultrasound-guided ESP blocks were performed in different regions of the specimens using 20ml of 0.01% methylene blue per block. The distribution of the dye was observed from the anterior side of the thorax, measuring the amount of intercostal spaces stained, before and after the removal of the parietal pleura, and the structures in which the stain was found were recorded. RESULTS: In all blocks of the ESP, dye was found in the paravertebral space, intercostal spaces, and in some cases in the prevertebral chain. The blocks had a mean of 4.6 intercostal spaces stained, with a maximum of 7 and a minimum of 3. The intensity of the dye was greater on the side of the injection, dorsal to the column, than that found in the ventral part below of the pleura. It was not possible to verify a clear channel through which the dye diffuses towards the previous zone. CONCLUSIONS: From the data collected in this study, it can be deduced that the blockade of the ESP has a mechanism of anaesthetic action similar to paravertebral blocks. The site from which the anaesthetic would cross from the posterior plane of the spine to the anterior region of the thorax was not clear, and should be investigated in future works.

Analysis and Classification of Voice Pathologies Using Glottal Signal Parameters.

The classification of voice diseases has many applications in health, in diseases treatment, and in the design of new medical equipment for helping doctors in diagnosing pathologies related to the voice. This work uses the parameters of the glottal signal to help the identification of two types of voice disorders related to the pathologies of the vocal folds: nodule and unilateral paralysis. The parameters of the glottal signal are obtained through a known inverse filtering method, and they are used as inputs to an Artificial Neural Network, a Support Vector Machine, and also to a Hidden Markov Model, to obtain the classification, and to compare the results, of the voice signals into three different groups: speakers with nodule in the vocal folds; speakers with unilateral paralysis of the vocal folds; and speakers with normal voices, that is, without nodule or unilateral paralysis present in the vocal folds. The database is composed of 248 voice recordings (signals of vowels production) containing samples corresponding to the three groups mentioned. In this study, a larger database was used for the classification when compared with similar studies, and its classification rate is superior to other studies, reaching 97.2%.

Effect of age on circulating immunoreactive and bioactive parathyroid hormone levels in women.

Although levels of serum immunoreactive parathyroid hormone (iPTH) increase with age in women, this could be caused by retention of non-biologically active PTH fragments by the aging kidney. In 102 normal women, aged 30 to 89 yr, serum iPTH increased with age by 58% (r = 0.33, p less than 0.001) with antiserum GP-1M (which has midmolecule specificity) and 43% (r = 0.32, p less than 0.001) with antiserum CH-12M (which may have whole molecule specificity); urinary cAMP/GFR excretion increased by 29% (r = 0.22, p less than 0.05). The results of these assays were validated by comparison with serum levels of biologically active PTH (BioPTH) in immunoextracts of serum followed by renal adenylate cyclase assay in a selected subgroup of 25 of the women. Serum BioPTH correlated with serum iPTH assessed by antiserum GP-1M (r = 0.48, p less than 0.05) and antiserum CH-12M (r = 0.48, p less than 0.05) but not with urinary cAMP. The data are consistent with an increase of parathyroid function with aging: clearly, we do not find decreased parathyroid function as would be expected if age-related bone loss was not mediated, in part, by PTH.

Genetics, local environment and health as factors influencing plasma carotenoids in wild American kestrels (Falco sparverius).

Carotenoids are important as pigments for bright coloration of animals, and as physiologically active compounds with a wide array of health-related functions. Carotenoid-dependent coloration may have evolved as a signal to conspecifics; however, factors that may limit availability of carotenoids are poorly known. We investigated how the acquisition of carotenoids may be constrained by availability in the environment, diet, genetic make-up and health status of wild American kestrels (Falco sparverius). Plasma concentrations of siblings at the time of fledging showed a high degree of resemblance; however, a cross-fostering experiment revealed that variance was largely explained by nest of rearing, rather than nest of origin, thus indicating a low genetic component. A multivariate analysis of attributes of nestlings (sex, size, plasma proteins, immune function), parental reproduction (laying date, clutch size) and rearing conditions (brood size, size hierarchy, nestling mortality) showed only a small significant effect of leucocyte differentials on carotenoid concentrations of nestlings. A strong environmental effect on plasma carotenoids was demonstrated by levels of adult kestrels being correlated within mated pairs, and having a significant association with the abundance of voles, the primary prey species, per territory.

The T-cell-mediated immune response and return rate of fledgling American kestrels are positively correlated with parental clutch size.

Life-history theory predicts that parents face a trade-off between the number and viability of the progeny they produce. We found evidence for an apparent trade-off in a free-living population of American kestrels (Falco sparverius), as larger clutches produced more but lighter fledglings. However, while the body mass of fledglings has traditionally been used as a measure of survival prospect, offspring immunocompetence should also play an important role. We thus measured the T-cell-mediated immune response of fledgling kestrels in relation to brood traits and nest-rearing conditions through a cross-fostering experiment. The immune response was positively correlated with the body condition of fledglings, but was also higher in those hatched from five-egg than four-egg clutches. These results were not influenced by other brood traits, nor by current exposure to stressors and infectious agents, as measured by serological variables. Such ability to resist pathogens may account for why the probability of offspring returning to the study area in subsequent years, when controlling for brood size, was higher for five-egg than four-egg clutches. These results suggest an optimal clutch size through maternal effects on offspring immunocompetence rather than a trade-off between the number and quality of the offspring.

Offspring body condition and immunocompetence are negatively affected by high breeding densities in a colonial seabird: a multiscale approach.

Why avian colonies vary in size and how food competition among nearby colonies affects offspring quality are still not completely understood. We simultaneously examined the effects of four scales of breeding density on two measures of offspring viability (body condition and T-cell-mediated immunity) in the colonial Magellanic penguin. Body condition of fledglings was inversely correlated with breeding density within 100 m(2) of nests, and decreased with increasing numbers of breeding pairs competing within the parental foraging ranges (100 km), probably as a result of density-dependent food depletion. The T-cell-mediated immune response was positively correlated with body condition, reflecting, to some extent, the previous breeding-density effects, and was negatively correlated with colony size, which may be related to social stress. However, given the effect of protein intake on cell immunity, this result could also indicate a thus far neglected cost of coloniality, namely the consumption of low-protein food to compensate for the depletion of optimal prey. These results were not influenced by other traits, nor by the current exposure of birds to parasites and diseases, as measured by serological variables. Since body condition and the T-cell-mediated immune response of fledgling birds are indicators of their survival and recruitment prospects, the costs we have identified can explain variability in colony size in relation to food competition with surrounding colonies, as well as the skewed distribution toward small colonies in this species.

Environmental and genetic variation in T-cell-mediated immune response of fledgling American kestrels.

We investigated genetic and environmental components of variance in avian T-cell-mediated immune response (CMI) through a cross-fostering experiment conducted on wild American kestrels (Falco sparverius). CMI was evaluated in vivo by an experimental challenge with phytohaemagglutinin, a T-cell mitogen, injected intradermally in fledglings. Additionally, we assessed two measures of nutritional condition (body mass and circulating plasma proteins) which could influence the variance components of CMI. A two-way nested ANOVA indicated that CMI of fledgling kestrels was explained more by the nest where the bird was reared (33% of the explained variance) than by the nest of origin (12%). Body mass was explained equally by familial and environmental components, while plasma proteins were only related to the rearing environment. CMI of fledglings was not related to their circulating plasma proteins, but was positively correlated with their body mass. Fledgling body mass seemed to be influenced by pre-hatching or post-hatching maternal effects prior to manipulation since resemblance in body mass of sibships at the age of manipulation was high (h 2≤0.58), and body mass at this age predicted body mass at fledging. Therefore, pre-manipulation parental effects on body mass, such as investment in egg size, could have inflated the familial effects on body mass of fledglings and then on its correlated CMI. When controlling for body mass, most of the variation in CMI of fledglings was explained by the nest where the bird was reared (36.6%), while the variance explained by the nest of origin (4%) was not significant. This means that environmental influences are major determinants of offspring CMI. The low proportion of variance explained by the familial component may have been due to the high correlation of CMI to fitness.

Diet explains interpopulation variation of plasma carotenoids and skin pigmentation in nestling white storks.

Carotenoids have a dietary origin in birds, but mechanisms by which they are absorbed in the gut, transported in the blood, metabolized at various sites, and deposited in the integument remain poorly understood. Variation in both plasma carotenoid levels and external color may reflect different access to dietary carotenoids or individual physiological differences in the uptake and deposition of carotenoids. We compared total plasma carotenoid concentration in nestling white storks (Ciconia ciconia) from 11 Spanish colonies in two consecutive years. The main food item in one of the colonies was the red swamp crayfish (Procambarus clarkii), a recently introduced species. Storks in the remaining colonies ate a variety of foods but no crayfish. Total plasma carotenoid levels in the colony where crayfish were consumed were about five times higher than in any other colony. These differences were maintained after controlling for the significant interyear variability, as well as for sex, age, and body mass of birds. Skin pigmentation also differed, being intensely orange in storks that consumed crayfish but white (unpigmented) in the remaining individuals. With thin-layer chromatography (TLC) and electronic absorption spectroscopy, astaxanthin was confirmed as the major carotenoid in crayfish as well as in the plasma, skin, and body fat of crayfish-eating storks, whereas lutein was the main carotenoid in plasma samples from the other colonies. These results indicate that a newly available carotenoid in the environment, astaxanthin, can be absorbed in large quantities from the gut and be transported in the blood before deposition in different tissues.

[Dual time point 18F-FDOPA PET as a tool for characterizing brain tumors]. / PET de doble fase con (18)F-FDOPA como instrumento para la caracterización de tumores cerebrales.

(18)F-FDOPA is an amino acid analogue used to evaluate presynaptic dopaminergic activity, which has aroused great interest in neuro-oncology. We have evaluated five (18)F-FDOPA PET studies of patients referred for study of parkinsonian syndrome. Two subjects had previously treated high-grade brain tumors, one nonspecific brain injury, and 2 subjects presented unexpected tumoral lesions. For all lesions SUVmax, time to SUVmax and tumor-to-normal grey matter SUVmax rate (T/N) were calculated, and 90 minutes (18)F-FDOPA kinetics were analyzed. Tumor lesions corresponded to three malignant neurocytomas, one meningioma, one pineocytoma and one intrasinusal hemangioma. Both malignant and benign tumors exhibited high uptake of (18)F-FDOPA well above the normal cortex. However, the analysis of the curve uptake displayed characteristic patterns that facilitate the characterization of tumor lesions. A dual phase maximum uptake was observed, with an early 10 minutes uptake in malignant lesions, and a late 60 to 90 minutes uptake in benign or low grade lesions.

Características de pacientes ingresados a la unidad de cuidado intensivo neonatal en la Clínica Universidad de La Sabana / Features of patients hospitalized to the newborn intensive care at Clínica Universidad de La Sabana

Introducción: Es pertinente conocer las características de los pacientes que ingresan a las unidades de cuidado intensivo neonatal para que las acciones en salud respondan a sus necesidades particulares. Objetivo: Caracterizar los pacientes que ingresaron a la Unidad de Cuidado Intensivo Neonatal (UCIN) de la Clínica de la Universidad de La Sabana de enero a diciembre del 2012. Materiales y Métodos: estudio retrospectivo con n=206 neonatos que ingresaron a la UCIN de la Clínica Universidad de La Sabana en el 2012, se revisaron las historias clínicas de los pacientes ingresados para identificar sus características, se calcularon frecuencias relativas y absolutas; y para las variables cuantitativas se describieron medidas de tendencia central y dispersión. Resultados: el 56,3% eran hombres, el promedio de edad gestacional de 36,5 semanas (SD 3,3 semanas), el peso promedio fue de 2625,9 g (SD 757,5 g). La mediana de los días de estancia fue de 4 (IQR: 2 a 9). El principal diagnóstico fue ictericia neonatal en (21,8%), el 22% de los pacientes requirieron ventilación mecánica (VM). La media de la edad gestacional y del peso en pacientes con requerimientos de VM fue de 32.7 semanas (SD: 3,7 semanas) y 1883 g (SD: 779 g) respectivamente, comparado con 37,6 semanas (SD: 2,2 semanas) y 2840 g (SD: 601 g) en los que no requirieron VM. Conclusiones: características como bajo peso al nacer, edad gestacional temprana y el uso de surfactante, se asociaron con el requerimiento de VM, adicionalmente la mortalidad calculada fue del 2,8%.

Introduction: It is relevant to know the characteristics of patients who enter to neonatal intensive care units in order to learn how to respond to their specific conditions and which health actions can be applied for their particular needs. Objective: The aim of this study is describe patients admitted at Clinica Universidad de La Sabana (Neonatal Intensive Care -NIC) from January to December 2012. Materials and Methods: Retrospective study with n=206 neonates admitted to the NIC at Clinica Universidad de La Sabana in 2012, medical records of patients admitted were reviewed to identify its characteristics, as well absolute and relative frequencies were calculated. In terms of quantitative variables, they were measured with central tendency and dispersion. Results: 56.3% of patients were men, the average gestational age was 36.5 weeks (SD 3.3 weeks), the average weight was 2625 gr (SD 757.5 gr). The median days of stay was 4 (IQR:2-9). The main diagnosis was neonatal icterus (21.8%); 22% of patient's required mechanical ventilation (MV). The mean gestational age and weight in patients with VM requirements was 32.7 weeks (SD: 3.7 weeks) and 1883 gr (SD: 779 gr) respectively. Contrasted with the gestational age and weight of newborns that not requiring VM was 37.6 weeks (SD 2.2 weeks) and 2840 gr (SD: 601 gr). Conclusions: Low birth weight, early gestational age and the use of surfactant, were associated with the requirement of VM, and the mortality found was 2.8% for the whole cohort.

Gliatrophic and gliatropic roles of PVF/PVR signaling during axon guidance.

Evidence of molecular and functional homology between vertebrate and Drosophila glia is limited, restricting the power of Drosophila as a model system to unravel the molecular basis of glial function. Like in vertebrates, in the Drosophila central nervous system glial cells are produced in excess and surplus glia are eliminated by apoptosis adjusting final glial number to axons. The underlying molecular mechanisms are largely unknown, as the only gliatrophic pathway known to date in flies is the EGFR and its ligands. The PDGFR signaling pathway plays a major role in regulating oligodendrocyte migration and number in vertebrates. Here, we show that the Drosophila PDGFR/VEGFR homologue PVR is required in midline glia during axon guidance for glial survival and migration, ultimately enabling axonal enwrapment. The midline glia migrate aided by the VUM and the MP1 midline neurons--sources of PVF ligands--and concomitantly interactions with neurons maintain midline glia survival. Upon loss of function for PVF/PVR signaling midline glia apoptosis increases, and gain of function induces supernumerary midline glia. Midline glial cells are displaced towards ectopic sources of PVF ligands. PVR signaling promotes midline glia survival through AKT and ERK pathways. This work shows that the PVR/PDGFR pathway plays conserved gliatrophic and gliatropic roles in subsets of glial cells in flies and vertebrates.