Factors influencing complications after 3-columns spinal osteotomies for fixed sagittal imbalance from multiple etiologies: a multicentric cohort study about 286 cases in 273 patients.

PURPOSE: Spinal osteotomies performed to treat fixed spinal deformities are technically demanding and associated with a high complications rate. The main purpose of this study was to analyze complications and their risk factors in spinal osteotomies performed for fixed sagittal imbalance from multiple etiologies. METHODS: The study consisted of a blinded retrospective analysis of prospectively collected data from a large multicenter cohort of patients who underwent 3-columns (3C) spinal osteotomy, between January 2010 and January 2017. Clinical and radiological data were compared pre- and post-operatively. Complications and their risk factors were analyzed. RESULTS: Two hundred eighty-six 3C osteotomies were performed in 273 patients. At 1 year follow-up, both clinical (VAS pain, ODI and SRS-22 scores) and radiological (SVA, SSA, loss of lordosis and pelvic version) parameters were significantly improved (p < 0.001). A total of 164 patients (59.2%) experienced at least 1 complication (277 complications). Complications-free survival rates were only 30% at 5 years. Most of those were mechanical (35.2%), followed by general (17.6%), surgical site infection (17.2%) and neurological (10.9%). Pre-operative neurological status [RR = 2.3 (1.32-4.00)], operative time (+ 19% of risk each additional hour) and combined surgery [RR = 1.76 (1.08-2.04)] were assessed as risk factors for overall complication (p < 0.05). The use of patient-specific rods appeared to be significantly associated with less overall complications [RR = 0.5 (0.29-0.89)] (p = 0.02). CONCLUSION: Spinal 3C osteotomies were efficient to improve both clinical and radiological parameters despite high rates of complication. Efforts should be made to reduce operative time which appears to be the strongest predictive risk factor for complication.

OCT4 expression in human embryonic stem cells: spatio-temporal dynamics and fate transitions.

The improved in vitro regulation of human embryonic stem cell (hESC) pluripotency and differentiation trajectories is required for their promising clinical applications. The temporal and spatial quantification of the molecular interactions controlling pluripotency is also necessary for the development of successful mathematical and computational models. Here we use time-lapse experimental data of OCT4-mCherry fluorescence intensity to quantify the temporal and spatial dynamics of the pluripotency transcription factor OCT4 in a growing hESC colony in the presence and absence of BMP4. We characterise the internal self-regulation of OCT4 using the Hurst exponent and autocorrelation analysis, quantify the intra-cellular fluctuations and consider the diffusive nature of OCT4 evolution for individual cells and pairs of their descendants. We find that OCT4 abundance in the daughter cells fluctuates sub-diffusively, showing anti-persistent self-regulation. We obtain the stationary probability distributions governing hESC transitions amongst the different cell states and establish the times at which pro-fate cells (which later give rise to pluripotent or differentiated cells) cluster in the colony. By quantifying the similarities between the OCT4 expression amongst neighbouring cells, we show that hESCs express similar OCT4 to cells within their local neighbourhood within the first two days of the experiment and before BMP4 treatment. Our framework allows us to quantify the relevant properties of proliferating hESC colonies and the procedure is widely applicable to other transcription factors and cell populations.

C1-C2 Injury: Factors influencing mortality, outcome, and fracture healing.

BACKGROUND: C1-C2 injury represents 25-40% of cervical injuries and predominantly occurs in the geriatric population. METHODS: A prospective multicentre study was conducted under the aegis of the french spine surgery society (SFCR) investigating the impact of age, comorbidities, lesion type, and treatment option on mortality, complications, and fusion rates. RESULTS: A total of 417 patients were recruited from 11 participating centres. The mean ± SD age was 66.6 ± 22 years, and there were 228 men (55%); 5.4% presented a neurological deficit at initial presentation. The most frequent traumatic lesion was C2 fracture (n = 308). Overall mortality was 8.4%; it was 2.3% among those aged ≤ 60 years, 5.0% 61-80 years, and 16.0% > 80 years (p < 0.001). Regarding complications, 17.8% of patients ≤ 70 years of age presented with ≥ 1 complication versus 32.3% > 70 years (p = 0.0009). The type of fracture did not condition the onset of complications and/or mortality (p > 0.05). The presence of a comorbidity was associated with a risk factor for both death (p = 0.0001) and general complication (p = 0.008). Age and comorbidities were found to be independently associated with death (p < 0.005). The frequency of pseudoarthrosis ranged from 0 to 12.5% up to 70 years of age and then constantly and progressively increased to reach 58.6% after 90 years of age. CONCLUSIONS: C1-C2 injury represents a serious concern, possibly life-threatening, especially in the elderly. We found a major impact of age and comorbidities on mortality, complications, and pseudarthrosis; injury pattern or treatment option seem to have a minimal effect.

Outcomes of surgical treatments of spinal metastases: a prospective study.

BACKGROUND: Owing to recent advances in cancer therapy, updated data are required for clinicians counselling patients on treatment of spinal metastases. OBJECTIVE: To analyse the outcomes of surgical treatments of spinal metastases. METHODS: Prospective and multicentric study that included consecutively patients operated on for spinal metastases between January 2016 and January 2017. Overall survival was calculated with the Kaplan-Meier method. Cox proportional hazard model was used to calculate hazard ratio (HR) analysing mortality risk according to preoperative Karnofsky performance status (KPS), mobility level and neurological status. RESULTS: A total of 252 patients were included (145 males, 107 females) aged a mean 63.3 years. Median survival was 450 days. Primary cancer sites were lung (21%) and breast (19%). Multiple spinal metastases involved 122 patients (48%). Concomitant skeletal and visceral metastases were noted in 90 patients (36%). Main procedure was laminectomy and posterior fixation (57%). Overall, pain and mobility level were improved postoperatively. Most patients had normal preoperative motor function (50%) and remained so postoperatively. Patients "bedbound" on admission were the less likely to recover. In-hospital death rate was 2.4% (three disease progression, one septic shock, one pneumonia, one pulmonary embolism). Complication rate was 33%, deep wound infection was the most frequent aetiology. Higher mortality was observed in patients with poorest preoperative KPS (KPS 0-40%, HR = 3.1, p < 0.001) and mobility level ("bedbound", HR = 2.16, p < 0.001). Survival seemed also to be linked to preoperative neurological function. CONCLUSION: Surgical treatments helped maintain reasonable condition for patients with spinal metastases. Intervention should be offered before patients' condition worsen to ensure better outcomes.

Correction to: Outcomes of surgical treatments of spinal metastases: a prospective study.

The correct name of F. Saihlan should be F. Sailhan.

Metabolic improvement in obese patients after duodenal-jejunal exclusion is associated with intestinal microbiota composition changes.

BACKGROUND: Intestinal microbiota have been suggested to play an important role in the pathogenesis of obesity and type 2 diabetes. Bariatric surgery improves both conditions and has been associated with changes in intestinal microbiota composition. We investigated the effect of a nonsurgical bariatric technique on intestinal microbiota composition in relation to metabolic improvement. METHODS: Seventeen patients with obesity and type 2 diabetes were treated with the nonsurgical duodenal-jejunal bypass liner, which excludes the proximal 60 cm small intestine from food. Fecal samples as well as metabolic parameters reflecting obesity and type 2 diabetes were obtained from the patients at baseline, after 6 months with the device in situ, and 6 months after explantation. RESULTS: After 6 months of treatment, both obesity and type 2 diabetes had improved with a decrease in weight from 106.1 [99.4-123.5] to 97.4 [89.4-114.0] kg and a decrease in HbA1c from 8.5% [7.6-9.2] to 7.2% [6.3-8.1] (both p < 0.05). This was paralleled by an increased abundance of typical small intestinal bacteria such as Proteobacteria, Veillonella, and Lactobacillus spp. in feces. After removal of the duodenal-jejunal bypass liner, fecal microbiota composition was similar to that observed at baseline, despite persistent weight loss. CONCLUSION: Improvement of obesity and type 2 diabetes after exclusion of the proximal 60 cm small intestine by treatment with a nonsurgical duodenal-jejunal bypass liner may be promoted by changes in fecal microbiota composition.

Exome-wide association of deltamethrin resistance in Aedes aegypti from Mexico.

Aedes aegypti is the major vector of a number of arboviruses that cause disease in humans. Without vaccines or pharmaceuticals, pyrethroid insecticides remain the major tool for public health protection. Pyrethroid resistance is now widespread. Replacement substitutions in the voltage-gated sodium channel (vgsc) that reduce the stability of pyrethroid binding account for most of the resistance, but metabolic mechanisms also inactivate pyrethroids. High-throughput sequencing and the A. aegypti L5 annotated physical map has allowed interrogation of the exome for genes and single-nucleotide polymorphisms associated with pyrethroid resistance. We exposed females of A. aegypti from Mexico to a deltamethrin discriminating dose to designate them as resistant (active after 1 h) or susceptible (knocked down with no recovery after 4 h). The vgsc on chromosome 3 had the highest association, followed by genes proximal to vgsc. We identified potential detoxification genes located singly (eg HPX8C) or within clusters in chromosome 2 [three esterase clusters, two of cytochrome P450 monooxygenases (CYP)] and chromosome 3 (one cluster of 16 CYP325 and seven CYP9 genes). Deltamethrin resistance in A. aegypti is associated with mutations in the vgsc gene and a large assortment of genes.

Antibacterial Activities of Copper Nanoparticles in Hybrid Microspheres.

Active hybrid microspheres were prepared by blending aqueous solutions of gelatine and chitosan with different concentrations of copper nanoparticles (0) (CuNPs) using emulsion-based crosslinking synthesis to obtain hybrid microspheres. The incorporation of CuNPs slightly affected the physical and chemical properties of the films. Microscopic surface structure (SEM), energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction (XRD) analysis confirmed the presence of elemental copper and the crystalline structure of the CuNPs in the hybrid matrix. The surface properties of CuNPs were studied by XPS analyses. The antimicrobial activity of CuNPs coated with chitosan (QO)/gelatine (GE) compared to the QO/GE matrix alone was investigated, using the agar diffusion and culture medium methods in Mueller-Hinton. The evaluation was performed using the Gram-negative bacterium E. coli and the Gram positive bacterium E. faecalis. The investigated microspheres showed antimicrobial activity. Hybrid microspheres with 40 mg of Cu, evaluated in liquid medium, inhibited the growth of E. coli by 56% and of E. faecalis by 40% compared to the matrix hybridised alone; in solid medium, the inhibition was 2.5-fold and 2.6-fold, respectively. Thus, these microspheres are a promising material for applications with medical uses.

Biological role of excretory-secretory proteins in endemic parasites of Latin America and the Caribbean.

Neglected tropical diseases (NTDs) share certain traits: they are parasitic infections, prevailing in tropical environments and affecting marginalized sectors of the population. Six NTDs - ascariasis, cysticercosis, echinococcosis, hookworm infection, onchocerciasis and trichuriasis - all of them endemic in Latin America and the Caribbean (LAC), are analysed in this work. This review aims to discuss key information on the function of excretory/secretory (E/S) proteins from these parasites in their infectivity, pathogeny and diagnosis. The modulation of the host immune system to favour the permanence and survival of the parasite is also discussed. An updated knowledge on the function of E/S molecules in endemic parasitoses in LAC may lead to new approaches for the clinical management and diagnosis of these diseases. In turn, this could allow us to optimize their treatment and make it more affordable - a relevant goal given the economic constraints that the region is facing.

[Vitamin D and pediatrics respiratory diseases]. / Vitamina D y enfermedades respiratorias pediátricas.

The better understanding of the global activity of vitamin D has led to an intense search for its involvement in non-skeletal diseases. This article presents an updated review of the relationship between vitamin D and pediatric respiratory pathology. A literature search was performed in PUBMED using free terms and MESH terms: vitamin D, asthma, respiratory system diseases, and bronchiolitis. Stu dies in human patients younger than 18 years and animals, published in English and Spanish until 2017 were included. 507 articles were found, of which 43 were included. Indirect evidence suggests a role of vitamin D and fetal lung maturation. In relation to pediatric pulmonary pathology, studies are scarce and inconclusive. Recent meta-analyses performed with individualized evaluation of the participants shows an important protective role of vitamin D supplementation in the prevention of severe asthma exacerbations and acute viral infections. In bronchiolitis, the results are contradictory, with no clear relationship between plasma levels and severity. There is not enough evidence to assess the benefits of vitamin D supplementation in cystic fibrosis and tuberculosis. A direct relationship between the severity of sleep-related breathing disorders and vitamin D plasma levels has recently been proposed, although the exact mechanisms involved in this association are unknown. Current information suggests that vitamin D supplementation may represent a cost-effective strategy in redu cing important causes of infant morbidity and mortality.

Correlated random walks of human embryonic stem cells in vitro.

We perform a detailed analysis of the migratory motion of human embryonic stem cells in two-dimensions, both when isolated and in close proximity to another cell, recorded with time-lapse microscopic imaging. We show that isolated cells tend to perform an unusual locally anisotropic walk, moving backwards and forwards along a preferred local direction correlated over a timescale of around 50 min and aligned with the axis of the cell elongation. Increasing elongation of the cell shape is associated with increased instantaneous migration speed. We also show that two cells in close proximity tend to move in the same direction, with the average separation of [Formula: see text]m or less and the correlation length of around 25 µm, a typical cell diameter. These results can be used as a basis for the mathematical modelling of the formation of clonal hESC colonies.

Long-term survivors after surgical management of metastatic spinal cord compression.

PURPOSE: Metastatic spinal cord compression (MSCC) incidences are increasing. Our objective was to identify predictive factors involved in long-term survival after use of a surgical approach. METHODS: We retrospectively analyzed all patients referred to our institution for MSCC who underwent surgery (N = 138). We identified patients with an overall survival (OS) rate greater than 2 years, compared their characteristics to the remaining patients, and performed recursive partitioning analysis (RPA). RESULTS: Median OS was 7.8 months (95 % confidence interval 4.4-11.2). Thirty-nine patients presented with OS ≥2 years. A comparative analysis found significant differences concerning the delay (first symptom-surgery, p < 0.001), number of systemic (p = 0.001) or bone metastases (p = 0.013), Karnofsky performance status (KPS) (p = 0.006), Frankel (p = 0.025), ASA scores (p < 0.001), weight loss (p = 0.003), hyperalgia (p = 0.002), chemotherapy use (p = 0.034), and primary tumor (p < 0.001). RPA classification identified six prognostic classes based on the ASA score, primary type, KPS, and systemic metastases. CONCLUSION: Long-term metastatic cancer survivor patients are an increasing population with specific characteristics.

Informed consent in colonoscopy: A comparative analysis of 2 methods.

BACKGROUND: The manner in which informed consent is obtained varies. The aim of this study is to evaluate the level of knowledge about colonoscopy and comparing 2 methods of obtaining informed consent. MATERIALS AND METHODS: A comparative, cross-sectional, observational study was conducted on patients that underwent colonoscopy in a public hospital (Group A) and in a private hospital (Group B). Group A received information verbally from a physician, as well as in the form of printed material, and Group B only received printed material. A telephone survey was carried out one or 2 weeks later. RESULTS: The study included a total of 176 subjects (group A [n=55] and group B [n=121]). As regards education level, 69.88% (n=123) of the patients had completed university education, 23.29% (n= 41) secondary level, 5.68% (n=10) primary level, and the remaining subjects (n=2) had not completed any level of education. All (100%) of the subjects knew the characteristics of the procedure, and 99.43% were aware of its benefits. A total of 97.7% received information about complications, 93.7% named some of them, and 25% (n=44) remembered major complications. All the subjects received, read, and signed the informed consent statement before the study. There were no differences between the groups with respect to knowledge of the characteristics and benefits of the procedure, or the receipt and reading of the consent form. Group B responded better in relation to complications (P=.0027) and group A had a better recollection of the major complications (P<.0001). Group A had a higher number of affirmative answers (P<.0001). CONCLUSIONS: The combination of verbal and written information provides the patient with a more comprehensive level of knowledge about the procedure.

Minimally invasive transmuscular approach for the treatment of lumbar herniated disc: far lateral lumbar disc herniation: a clinical study. Applications for cervical and thoracic disc herniation.

AIM: In this study, we are using a recently developed method: a minimally invasive retractor system and an operating microscope to treat far lateral lumbar herniated disc. This method decreases tissue dissection and blood loss, and improves postoperative recovery. METHODS: This is a retrospective study of 46 patients, there was 25 female and 21 male. They all underwent minimal invasive surgery. The average age was 56 years old (19-83 years). Lumbar disc herniation is a common pathology. Far lateral disc herniation accounts for 2.6% to 11.2% of all lumbar disc herniation. A few surgical techniques have been describes to treat this type of disc pathology. All patients were operated under general anesthesia. The fluoroscopic guidance was absolutely necessary. A 12-15 mm skin incision was made on the side of the disc herniation (30 mm from the midline). Then, we inserted a tubular retractor system (muscle splitting approach) followed by a 14 mm diameter-working channel. Under operating microscope the pars interarticularis was dreamed to expose the nerve root and the disc. After removing the intertransverse ligament, we removed the herniated disc. RESULTS: The average time of surgery was 55 min. The operating time decreased with the experience of the surgical team. Postoperatively the radicular pain was around 2 (using an analogical visual scale), over 7 preoperatively. The length of hospitalization was 3 days. There were no complications in our study. The average follow-up was 2 years (6-36 months). There was no complication, no postoperative infection. CONCLUSION: This technique combines the advantages of endoscopic surgery and microscope guided surgery (3D vision) and provides good functional results in this study.

[Current problems in training of minimally invasive surgery: vision of residents in pediatric surgery]. / Problemas actuales en la formación en cirugía mínimamente invasiva: visión de los residentes de Cirugía pediátrica.

INTRODUCTION: Minimally Invasive Surgery (MIS) is getting more and more important in our specialty. However, the formation of the residents on MIS is, in many cases, irregular. The purpose of this study is to assess the state of training in MIS among the residents of Pediatric Surgery and their potential weaknesses. MATERIAL AND METHODS: An electronic survey was distributed among 71 residents of Pediatric Surgery from 17 national hospitals. RESULTS: The response rate was 70.2%.100% of the residents are interested in a broadening of training activities in MIS. The main areas of interest are gastrointestinal (92%) and thoracic (47%) surgery. Only 57% have access to training facilities and less than half of them attend to courses and conferences. 80% believe that they are not given adequate attention from specialized associations. 52% think they should do rotations at referral centers, 86% that courses and seminars should be enhanced, and 44% that the responsibility of the resident in surgery should be increased. The main defects encountered in their training are scarce volume of patients, lack of financial support and overcoming the learning curve of surgeons in their services. CONCLUSIONS: Despite the advance of the MIS, resident's training in this discipline still has shortcomings, as expressed in their views. Knowledge of the current state of training should be the starting point for designing a training strategy that ensures adequate skills.

Structural characterization, stability, and cytocompatibility study of chitosan BaTiO3@ZnO:Er heterostructures.

New imaging agents are required in cancer diagnosis to enhance the diagnostic accuracy, classification, and therapeutic management of tumors. Nanomaterials have emerged as a promising alternative to developing new nanostructures with imaging applications. In this study, a heterostructure based on barium titanate (BT), zinc oxide (ZnO), and erbium (Er) was prepared and coated with Chitosan (CS) to investigate their stability and compatibility with biological systems. The structure, particle morphology, luminescence properties, stability, and cytotoxicity of different nanoparticles (NPs) were assessed. The results demonstrated the formation of a [BT@ZnO:Er]-CS heterostructure, which is consistent with the relative intensities and positions of peaks in the X-ray diffraction (XRD) with an average crystallite size of ~76 nm. The electrokinetic measurement results indicate that the coated NPs are the most stable and have an average size close to 200 nm when the pH is between 3 and 5. Finally, we presented a cytotoxicity study of naked and CS-coated NPs. The results indicate that naked NPs exhibit varying cellular toxicity, as indicated by decreased cell viability, morphological changes, and an increase in an apoptotic marker. The CS-coated NPs prevented the cytotoxic effect of the naked NPs, demonstrating the significance of CS as a stabilizing agent.

Additive Manufactured Piezoelectric-Driven Miniature Gripper.

In several cases, it is desirable to have prototypes of low-cost fabrication and adequate performance. In academic laboratories and industries, miniature and microgrippers can be very useful for observations and the analysis of small objects. Piezoelectrically actuated microgrippers, commonly fabricated with aluminum, and with micrometer stroke or displacement, have been considered as Microelectromechanical Systems (MEMS). Recently, additive manufacture using several polymers has also been used for the fabrication of miniature grippers. This work focuses on the design of a piezoelectric-driven miniature gripper, additive manufactured with polylactic acid (PLA), which was modeled using a pseudo rigid body model (PRBM). It was also numerically and experimentally characterized with an acceptable level of approximation. The piezoelectric stack is composed of widely available buzzers. The aperture between the jaws allows it to hold objects with diameters lower than 500 µm, and weights lower than 1.4 g, such as the strands of some plants, salt grains, metal wires, etc. The novelty of this work is given by the miniature gripper's simple design, as well as the low-cost of the materials and the fabrication process used. In addition, the initial aperture of the jaws can be adjusted, by adhering the metal tips in the required position.

Influence of TiO2 on prebiotic thermal synthesis of the Gly-Gln polymer.

The role of the titanium dioxide (rutile and anatase) with and without room light on the thermal synthesis of the glycine-L-glutamine (Gly-Gln) polymer is described. The efficiency in percentage of polymerization with room light was increased in 6% in the presence of rutile and in 23% in the presence of anatase. The thermal synthesis in the molten state was carried out in the absence and presence of both oxides. In all cases, the vibrational spectra showed characteristic group frequencies corresponding to a polypeptide structure. No spectral differences were observed by room light effect on the polymer on rutile. However, the polymer obtained in the presence of anatase and room light shows spectral changes associated with the formation of shorter new abundant and conformationally different species compared with the original polymer. The SEM-EDX characterization of the solid phase involved in the thermal synthesis showed that the morphology of the polypeptide is different in the presence of rutile compared to anatase. The SDS-PAGE and GPC results suggest that smaller chains are formed in the presence of both oxides and the distribution of the size and weight of each polymer molecule is completely different when the condensation is performed in the presence of anatase or rutile. Nuclear magnetic resonance analyses confirmed the incorporation of both Gly and Gln residues in the polymers, with a prevalence of Gly. Both possible sequences N-GlyGln-C and N-GlnGly-C were also detected.

[Cardiovascular and respiratory changes during laparoscopy in neonates and infants]. / Cambios cardiovasculares y ventilatorios durante la laparoscopia en neonatos y lactantes pequeños.

The pneumoperitoneum induced during laparoscopy has cardiovascular and respiratory effects that have to be taken into account to perform laparoscopic procedures in neonates and small infants. The aim of this paper is to describe the hemodynamic and ventilatory changes that occur in a group of these patients undergoing standard laparoscopic procedure. We performed a retrospective review of patients undergoing laparoscopic pyloromyotomy in our institution. We collected demographic data, data from the intervention, outcome and complications and hemodynamic parameters (heart rate--HR--and blood pressure--BP--) and respiratory (O2 saturation--SO2--and exhaled CO2--ECO2--) at different times during surgery. We performed statistical analysis of these data. We reviewed a total of 55 charts. Mean age was 34 days and average weight 3,785 g. All patients were ventilated with pressure control mode and received maintenance fluid therapy. BP, HR and SO2 were stable throughout the surgery not showing significant differences. The ECO2 increased significantly after inflation, however it was controlled by increasig respiratory rate. In conclusion, the hemodynamic and ventilatory response in these patients is controllable with anesthetic and surgical measures but it is important to consider the possible consequences of pneumoperitoneum in this group of patients.