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Transthoracic access emerges as an innovative approach to reach lesions in the upper hepatic segments, especially in patients with prior surgeries. This study evaluates transthoracic access for these resections through a retrospective single-center analysis of demographic data, surgical techniques, and postoperative outcomes of 353 liver surgeries, revealing promising results with minimal complications. Transthoracic access and pneumoperitoneum establishment via the transthoracic route, combined with intercostal trocar insertion, offer a viable alternative for minimally invasive liver surgeries.
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INTRODUCTION: Hepatectomies associated with vascular resections pose a technical challenge for surgeons, involving multiple reconstruction techniques. Moreover, adding clinical and surgical risks in the postoperative setting of these complex procedures are mainly due to prolonged surgical periods and potential complications inherent to vascular manipulation. Leveraging the expertise of a Cancer Center, we propose an institutional assessment utilizing the case series from A. C. Camargo Cancer Center in hepatectomies associated with vascular resection, evaluating postoperative complications and outcomes while highlighting clinical, laboratory, pathological, and surgical factors that may influence results. OBJECTIVE: To assess mortality and morbidity associated with hepatectomies involving vascular resection. MATERIALS AND METHODS: From a prospective database, a study was performed evaluating postoperative survival and morbidity using scoring systems such as Clavien-Dindo through a cohort analysis. RESULTS: From a total of 1021 liver resections for a period of 10 years, 31 cases were evaluated from a unique cancer center in Brazil! Factors such as the performance of major hepatectomies, the need for blood transfusion, and the administration of neoadjuvant or adjuvant systemic therapy did not appear to influence the outcome of morbidity or mortality. However, the resection of the associated bile duct and the type of vascular resection seemed to influence morbidity outcomes with statistical significance (p = 0.006+ ). CONCLUSION: Hepatectomies associated with vascular resections are safe in selected cases and when performed in referral centers. Factors such as associated bile duct resection and type of vascular resection should be considered for procedure indication.
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OBJECTIVE: New characterized carbohydrate-active enzymes are needed for use as tools to discriminate complex carbohydrate structural features. Fungal glycoside hydrolase family 3 (GH3) ß-xylosidases have been shown to be useful for the structural elucidation of glucuronic acid (GlcA) and arabinofuranose (Araf) substituted oligoxylosides. A homolog of these GH3 fungal enzymes from the bacterium Segatella baroniae (basonym Prevotella bryantii), Xyl3C, has been previously characterized, but those studies did not address important functional specificity features. In an interest to utilize this enzyme for laboratory methods intended to discriminate the structure of the non-reducing terminus of substituted xylooligosaccharides, we have further characterized this GH3 xylosidase. RESULTS: In addition to verification of basic functional characteristics of this xylosidase we have determined its mode of action as it relates to non-reducing end xylose release from GlcA and Araf substituted oligoxylosides. Xyl3C cleaves xylose from the non-reducing terminus of ß-1,4-xylan until occurrence of a penultimate substituted xylose. If this substitution is O2 linked, then Xyl3C removes the non-reducing xylose to leave the substituted xylose as the new non-reducing terminus. However, if the substitution is O3 linked, Xyl3C does not hydrolyze, thus leaving the substitution one-xylose (penultimate) from the non-reducing terminus. Hence, Xyl3C enables discrimination between O2 and O3 linked substitutions on the xylose penultimate to the non-reducing end. These findings are contrasted using a homologous enzyme also from S. baroniae, Xyl3B, which is found to yield a penultimate substituted nonreducing terminus regardless of which GlcA or Araf substitution exists.
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Xilanos , Xilosa , Xilosidasas , Xilosidasas/metabolismo , Xilosidasas/genética , Xilosidasas/química , Xilanos/metabolismo , Xilosa/metabolismo , Especificidad por Sustrato , Prevotella/enzimología , Prevotella/genética , Oligosacáridos/metabolismo , Oligosacáridos/química , Glucuronatos/metabolismo , Arabinosa/análogos & derivadosRESUMEN
BACKGROUND: Restoring hand functionality is critical for fostering independence in individuals with neurological disorders. Various therapeutic approaches have emerged to address motor function restoration, with music-based therapies demonstrating notable advantages in enhancing neuroplasticity, an integral component of neurorehabilitation. Despite the positive effects observed, there remains a gap in the literature regarding implementing music treatments in neurorehabilitation, such as Neurologic Music Therapy (NMT), especially in conjunction with emerging fields like wearable devices and game-based therapies. METHODS: A literature search was conducted in various databases, including PubMed, Scopus, IEEE Xplore, and ACM Digital Library. The search was performed using a literature search methodology based on keywords. Information collected from the studies pertained to the approach used in music therapy, the design of the video games, and the types of wearable devices utilized. RESULTS: A total of 158 articles were found, including 39 from PubMed, 34 from IEEE Xplore, 48 from Scopus, 37 from ACM Digital Library, and 35 from other sources. Duplicate entries, of which there were 41, were eliminated. In the first screening phase, 152 papers were screened for title and abstract. Subsequently, 89 articles were removed if they contained at least one exclusion criterion. Sixteen studies were considered after 63 papers had their full texts verified. CONCLUSIONS: The convergence of NMT with emerging fields, such as gamification and wearable devices designed for hand functionality, not only expands therapeutic horizons but also lays the groundwork for innovative, personalized approaches to neurorehabilitation. However, challenges persist in effectively incorporating NMT into rehabilitation programs, potentially hindering its effectiveness.
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Mano , Musicoterapia , Rehabilitación Neurológica , Juegos de Video , Dispositivos Electrónicos Vestibles , Humanos , Rehabilitación Neurológica/instrumentación , Rehabilitación Neurológica/métodos , Musicoterapia/instrumentación , Musicoterapia/métodos , Mano/fisiologíaRESUMEN
Stuttering, affecting approximately 1% of the global population, is a complex speech disorder significantly impacting individuals' quality of life. Prior studies using electromyography (EMG) to examine orofacial muscle activity in stuttering have presented mixed results, highlighting the variability in neuromuscular responses during stuttering episodes. Fifty-five participants with stuttering and 30 individuals without stuttering, aged between 18 and 40, participated in the study. EMG signals from five facial and cervical muscles were recorded during speech tasks and analyzed for mean amplitude and frequency activity in the 5-15 Hz range to identify significant differences. Upon analysis of the 5-15 Hz frequency range, a higher average amplitude was observed in the zygomaticus major muscle for participants while stuttering (p < 0.05). Additionally, when assessing the overall EMG signal amplitude, a higher average amplitude was observed in samples obtained from disfluencies in participants who did not stutter, particularly in the depressor anguli oris muscle (p < 0.05). Significant differences in muscle activity were observed between the two groups, particularly in the depressor anguli oris and zygomaticus major muscles. These results suggest that the underlying neuromuscular mechanisms of stuttering might involve subtle aspects of timing and coordination in muscle activation. Therefore, these findings may contribute to the field of biosensors by providing valuable perspectives on neuromuscular mechanisms and the relevance of electromyography in stuttering research. Further research in this area has the potential to advance the development of biosensor technology for language-related applications and therapeutic interventions in stuttering.
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Electromiografía , Músculos Faciales , Habla , Tartamudeo , Humanos , Electromiografía/métodos , Masculino , Adulto , Femenino , Tartamudeo/fisiopatología , Habla/fisiología , Músculos Faciales/fisiología , Músculos Faciales/fisiopatología , Fenómenos Biomecánicos/fisiología , Adulto Joven , Adolescente , Contracción Muscular/fisiologíaRESUMEN
We demonstrate facile fabrication of highly filled, lightweight organic-inorganic composites comprising polyurethanes covalently linked with naturally occurring clinoptilolite microparticles. These polyurethane/clinoptilolite (PUC) composites are shown to mitigate particle aggregation usually observed in composites with high particle loadings and possess enhanced thermal insulation and acoustic attenuation compared with conventionally employed materials (e.g., drywall and gypsum). In addition to these functional properties, the PUC composites also possess flexural strengths and strain capacities comparable to and higher than ordinary Portland cement (OPC), respectively, while being â¼1.5× lighter than OPC. The porosity, density, and mechanical and functional properties of these composites are tuned by systematically varying their composition (diisocyanate, polyurethane, and inorganic contents) and the nature of the organic (reactivity and source of polyol) components. The fabrication process involves mild curing conditions and uses commonly available reagents (naturally occurring aluminosilicate particles, polyols, and diisocyanate), thereby making the process scalable. Finally, the composite properties are shown to be independent of the polyol source (virgin or recycled), underlining the generality of this approach for the scalable utilization of recycled polyols.
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In May 2023, pennycress (Thlaspi arvense, L.) lines undergoing seed production in the Walnut Street Greenhouse at the University of Wisconsin-Madison displayed symptoms of chlorosis and black necrotic leaf spots (Fig. S1-A). Lesions eventually enlarged to 1-2 cm in diameter, became necrotic, and coalesced to cover a substantial portion of leaves. Symptoms were observed in ~30% of the pennycress lines adversely affecting overall growth and reproduction. Symptomatic leaves were surface sterilized for 30 seconds in 0.75% sodium hypochlorite, rinsed in sterile deionized water, and bacteria were isolated using three-phase streaking of symptomatic tissue onto KB medium (King et al., 1954). Single colonies of three isolates (creamy white to yellow) from this initial isolation were streaked onto KB medium to obtain pure cultures. Individual colonies were transferred for growth overnight in nutrient broth (Difco) and an equal amount of the broth was added to 30% glycerol in deionized (di) water and stored at -80 °C. To validate Koch's Postulates, bacteria were grown from these stocks on Yeast Dextrose Calcium Carbonate medium (Wilson et al., 1967) and were used to inoculate 5-week-old pennycress plants in the greenhouse. The bacteria were grown for 48 hours at 26°C, suspended in 300 ml of 0.05 M PBS buffer (pH=7.2) for inoculum preparation. Plants were inoculated with three bacterial isolates (approx. 108 CFU/ml) by piercing the mid veins or hydathodes with a sterilized toothpick dipped in the suspension. Inoculated plants were then enclosed in clear plastic bags for 24-48 hours and maintained in the greenhouse at a constant temperature of 26°C with a 16-hour photoperiod. After seven days, water-soaked lesions appeared on the inoculated leaves, eventually developing into the characteristic black spots (Fig. S1-B). DNA from the original isolates was extracted, and 16S PCR and sequencing of the positive bands was done. The negative control only produced brown spots at the site of inoculation (Fig. S1-C). The primer sequences were as follows: 27F: AGAGTTTGATCMTGGCTCAG; 1492R: GGTTACCTTGTTACGACTT (Eden et al., 1991; Weisburg et al., 1991). A BLAST analysis showed that the isolates had an E value of 0.0 to the genus Xanthomonas as well as 100% identity. Amplification and sequencing of the bacterium using gyrB amplicons revealed a 99-100% pairwise match with Xc. To enhance taxonomy resolution and confirm the identity of these isolates, the complete genomes of three samples were sequenced using NextSeq2000 Illumina platform (NCBI bioproject ID PRJNA1040293). Average Nucleotide Identity (ANI) analysis was conducted with representative strains from the Xc species (Dubrow et al., 2022), using PanExplorer (Dereeper et al., 2020) featuring integrated FastANI module (Jain et al., 2018). The isolates genomes exhibited over 98% identity and clustered with that of Xc pv. incanae and Xc pv. barbarae (Fig S2). Further work will be required to identify the pathovar of Xc identified in this study through phenotypic host range assay. This marks the first documented case of Xc in pennycress in the Midwestern US. Given the potential use of pennycress as a cover crop in the region, further investigations are warranted to assess its economic impact on production and develop management strategies.
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Introduction melanoma patients who become stage III after a positive sentinel node biopsy (SNB) may have several patterns of recurrence patients and methods retrospective analysis of melanoma patients who have undergone SNB in a single institution from 2000 to 2015. Results There were 111 recurrences (45.1%) among 246 (20.3%) SNB positive patients and median DRFS was 77.7 months. After initial treatment, further recurrences occurred in 68 (77.3%) patients, regardless the site of initial recurrence conclusions multimodal strategies are recommended to achieve better results when managing stage III melanoma patients after a positive SNB.
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Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/cirugía , Melanoma/patología , Estudios Retrospectivos , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , Escisión del Ganglio LinfáticoRESUMEN
MppQ is an enzyme of unknown function from Streptomyces hygroscopicus (ShMppQ) that operates in the biosynthesis of the nonproteinogenic amino acid L-enduracididine (L-End). Since L-End is a component of several peptides showing activity against antibiotic-resistant pathogens, understanding its biosynthetic pathway could facilitate the development of chemoenzymatic routes to novel antibiotics. Herein, we report on the crystal structures of ShMppQ complexed with pyridoxal-5'-phosphate (PLP) and pyridoxamine-5'-phosphate (PMP). ShMppQ is similar to fold-type I PLP-dependent aminotransferases like aspartate aminotransferase. The tertiary structure of ShMppQ is composed of an N-terminal extension, a large domain, and a small domain. The active site is placed at the junction of the large and small domains and includes residues from both protomers of the homodimer. We also report the first functional characterization of MppQ, which we incubated with the enzymatically produced 2-ketoenduracidine and observed the conversion to L-End, establishing ShMppQ as the final enzyme in L-End biosynthesis. Additionally, we have observed that MppQ has a relatively high affinity for 2-keto-5-guanidinovaleric acid (i.e., 2-ketoarginine), a shunt product of MppP, indicating the potential role of MppQ in increasing the efficiency of L-End biosynthesis by converting 2-ketoarginine back to the starting material, l-arginine. A panel of potential amino-donor substrates was tested for the transamination activity against a saturating concentration of 2-ketoarginine in end-point assays. Most l-Arg was produced with l-ornithine as the donor substrate. Steady-state kinetic analysis of the transamination reaction with l-Orn and 2-ketoarginine shows that the kinetic constants are in line with those for the amino donor substrate of other fold-type I aminotransferases.
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Fosfato de Piridoxal , Transaminasas , Cinética , Transaminasas/metabolismo , Fosfato de Piridoxal/metabolismo , Fosfatos , Especificidad por Sustrato , Cristalografía por Rayos XRESUMEN
Introduction: The Society for Education in Anesthesia (SEA) promotes dissemination of discoveries and innovations. We investigated the rate of publication of SEA Spring Meeting abstracts, hypothesizing that Research abstracts were published more frequently than Innovative Curriculum abstracts. We also studied the time between abstract presentation and publication and tracked the journals in which they were published. Methods: All abstracts presented at SEA spring meetings from 2011-2019 were included. We searched PubMed for published articles that were based on those SEA abstracts. We calculated the overall publication rate and the respective publication rates for Research and Innovative Curriculum abstracts. We calculated odds ratio (OR) and performed the Pearson χ2 test to compare publication rates between Research abstracts and Innovative Curriculum abstracts. We calculated the mean number of years between meeting presentation and publication and tabulated the number of works published in each journal. Results: A total of 351 abstracts (128 Research and 223 Curriculum) were presented at SEA spring meetings. The overall publication rate was 15% (52/351). Research abstracts were published more frequently than Curriculum abstracts: 24.2% (31/128) versus 9.4% (21/223); OR = 3.1 (95% confidence interval, 1.7-5.6); P = .0003. The mean time from presentation to publication was 1.7 ± 1.3 years. The works appeared in 20 different journals. Conclusion: SEA Spring Meeting abstracts were published less frequently than abstracts from other medical professional society meetings (21%-72.3%). Although the lower publication rate of Innovative Curriculum abstracts unique to the SEA meeting largely explains this shortfall, a relatively low publication rate, even for the Research abstracts, signals opportunities for growth.
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The pozzolanic reaction of fly ashes with calcium-based additives can be effectively used to solidify and chemically stabilize (S&S process) highly concentrated brines inside a cementitious matrix. However, complex interactions between the fly ash, the additive, and the brine typically affect the phases formed at equilibrium, and the resulting solid capacity to successfully encapsulate the brine and its contaminants. Here, the performances of two types of fly ash (a Class C and Class F fly ash) are assessed when combined with different additives (two types of cement, or lime with and without NaAlO2), and two types of brine (NaCl or CaCl2) over a range of concentrations (0 ≤ [Cl-] ≤ 2 M). The best performing matrices - i.e., the matrices with the highest Cl-containing phases content - were identified using XRD and TGA. The experimental results were then combined with thermodynamic modeling to dissociate the contribution of the fly ash from that of the additives. All results were implemented in a machine learning model that showed good accuracy at predicting the fly ash degree of reaction, allowing for the robust prediction of extended systems performance when combined with thermodynamic modeling.
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Ceniza del Carbón , Eliminación de Residuos , Eliminación de Residuos/métodos , Calcio , Cloruro de Sodio , Cloruro de CalcioRESUMEN
We present the mass balances associated with carbon dioxide (CO2) removal (CDR) using seawater as both the source of reactants and as the reaction medium via electrolysis following the "Equatic" (formerly known as "SeaChange") process. This process, extensively detailed in La Plante E.C.; ACS Sustain. Chem. Eng.2021, 9, ( (3), ), 1073-1089, involves the application of an electric overpotential that splits water to form H+ and OH- ions, producing acidity and alkalinity, i.e., in addition to gaseous coproducts, at the anode and cathode, respectively. The alkalinity that results, i.e., via the "continuous electrolytic pH pump" results in the instantaneous precipitation of calcium carbonate (CaCO3), hydrated magnesium carbonates (e.g., nesquehonite: MgCO3·3H2O, hydromagnesite: Mg5(CO3)4(OH)2·4H2O, etc.), and/or magnesium hydroxide (Mg(OH)2) depending on the CO32- ion-activity in solution. This results in the trapping and, hence, durable and permanent (at least â¼10â¯000-100â¯000 years) immobilization of CO2 that was originally dissolved in water, and that is additionally drawn down from the atmosphere within: (a) mineral carbonates, and/or (b) as solvated bicarbonate (HCO3-) and carbonate (CO32-) ions (i.e., due to the absorption of atmospheric CO2 into seawater having enhanced alkalinity). Taken together, these actions result in the net removal of â¼4.6 kg of CO2 per m3 of seawater catholyte processed. Geochemical simulations quantify the extents of net CO2 removal including the dependencies on the process configuration. It is furthermore indicated that the efficiency of realkalinization of the acidic anolyte using alkaline solids depends on their acid neutralization capacity and dissolution reactivity. We also assess changes in seawater chemistry resulting from Mg(OH)2 dissolution with emphasis on the change in seawater alkalinity and saturation state. Overall, this analysis provides direct quantifications of the ability of the Equatic process to serve as a means for technological CDR to mitigate the worst effects of accelerating climate change.
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BACKGROUND: Costello syndrome (CS) is a rare genetic condition characterized by dysregulation of the signaling pathway, phenotypic alteration due to fetal macrosomia or growth retardation, facial abnormalities, loose skin, cardiovascular abnormalities, and a variable degree of intellectual disability. CASE PRESENTATION: We describe the case of a 20-month-old male patient with fetal macrosomia and polyhydramnios, presenting psychomotor development delay and growth limitation during the first months of life. CS was diagnosed at four months of age after detecting a variant of the HRAS gene c.35G > C (p.G12A). A clinical description of his condition was recorded throughout his life, including cardiovascular diseases, endocrine disorders, and recurrent infections. At 20 months of age, after presenting events of marked hypotonia and generalized seizures, brain magnetic resonance revealed symmetrical lesions of the infra- and supratentorial white matter in both cerebral hemispheres, which resulted in the diagnosis of cerebral leukodystrophy. The patient had a rapid and progressive deterioration that eventually led to death. CONCLUSIONS: This is the first report of a case of CS in Peru. In addition, this is a case that presented with multisystemic conditions culminating in leukodystrophy, which is a rare event according to the literature.
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Anomalías Cardiovasculares , Síndrome de Costello , Discapacidad Intelectual , Embarazo , Femenino , Humanos , Masculino , Lactante , Síndrome de Costello/complicaciones , Síndrome de Costello/diagnóstico , Síndrome de Costello/genética , Macrosomía Fetal , Genes ras , Discapacidad Intelectual/genéticaRESUMEN
Knowledge graphs have gained increasing popularity in the last decade in science and technology. However, knowledge graphs are currently relatively simple to moderate semantic structures that are mainly a collection of factual statements. Question answering (QA) benchmarks and systems were so far mainly geared towards encyclopedic knowledge graphs such as DBpedia and Wikidata. We present SciQA a scientific QA benchmark for scholarly knowledge. The benchmark leverages the Open Research Knowledge Graph (ORKG) which includes almost 170,000 resources describing research contributions of almost 15,000 scholarly articles from 709 research fields. Following a bottom-up methodology, we first manually developed a set of 100 complex questions that can be answered using this knowledge graph. Furthermore, we devised eight question templates with which we automatically generated further 2465 questions, that can also be answered with the ORKG. The questions cover a range of research fields and question types and are translated into corresponding SPARQL queries over the ORKG. Based on two preliminary evaluations, we show that the resulting SciQA benchmark represents a challenging task for next-generation QA systems. This task is part of the open competitions at the 22nd International Semantic Web Conference 2023 as the Scholarly Question Answering over Linked Data (QALD) Challenge.
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BACKGROUND: Among patients who express interest in bariatric surgery, dropout rates from bariatric surgery programs are reported as high as 60%. There is a lack of understanding how we can better support patients to obtain treatment of this serious chronic disease. METHODS: Semi-structured interviews with individuals who dropped out of bariatric surgery programs from three clinical sites were conducted. Transcripts were iteratively analyzed to understand patterns clustering around codes. We mapped these codes to domains of the Theoretical Domains Framework (TDF) which will serve as the basis of future theory-based interventions. RESULTS: Twenty patients who self-identified as 60% female and 85% as non-Hispanic White were included. The results clustered around codes of "perceptions of bariatric surgery," "reasons for not undergoing surgery," and "factors for re-considering surgery." Major drivers of attrition were burden of pre-operative workup requirements, stigma against bariatric surgery, fear of surgery, and anticipated regret. The number and time for requirements led patients to lose their initial optimism about improving health. Perceptions regarding being seen as weak for choosing bariatric surgery, fear of surgery itself, and possible regret over surgery grew as time passed. These drivers mapped to four TDF domains: environmental context and resources, social role and identity, emotion, and beliefs about consequences, respectively. CONCLUSIONS: This study uses the TDF to identify areas of greatest concern for patients to be used for intervention design. This is the first step in understanding how we best support patients who express interest in bariatric surgery achieve their goals and live healthier lives.
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Cirugía Bariátrica , Humanos , Femenino , Masculino , Cirugía Bariátrica/psicología , Emociones , Miedo , Investigación CualitativaRESUMEN
Globally, 2.5% of upper limb amputations are transhumeral, and both mechanical and electronic prosthetics are being developed for individuals with this condition. Mechanics often require compensatory movements that can lead to awkward gestures. Electronic types are mainly controlled by superficial electromyography (sEMG). However, in proximal amputations, the residual limb is utilized less frequently in daily activities. Muscle shortening increases with time and results in weakened sEMG readings. Therefore, sEMG-controlled models exhibit a low success rate in executing gestures. The LIBRA NeuroLimb prosthesis is introduced to address this problem. It features three active and four passive degrees of freedom (DOF), offers up to 8 h of operation, and employs a hybrid control system that combines sEMG and electroencephalography (EEG) signal classification. The sEMG and EEG classification models achieve up to 99% and 76% accuracy, respectively, enabling precise real-time control. The prosthesis can perform a grip within as little as 0.3 s, exerting up to 21.26 N of pinch force. Training and validation sessions were conducted with two volunteers. Assessed with the "AM-ULA" test, scores of 222 and 144 demonstrated the prosthesis's potential to improve the user's ability to perform daily activities. Future work will prioritize enhancing the mechanical strength, increasing active DOF, and refining real-world usability.
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Miembros Artificiales , Humanos , Implantación de Prótesis , Amputación Quirúrgica , Electroencefalografía , ElectromiografíaRESUMEN
Lipoic acid is an eight-carbon sulfur-containing biomolecule that functions primarily as a cofactor in several multienzyme complexes. It is biosynthesized as an attachment to a specific lysyl residue on one of the subunits of these multienzyme complexes. In Escherichia coli and many other organisms, this biosynthetic pathway involves two dedicated proteins: octanoyltransferase (LipB) and lipoyl synthase (LipA). LipB transfers an n-octanoyl chain from the octanoyl-acyl carrier protein to the target lysyl residue, and then, LipA attaches two sulfur atoms (one at C6 and one at C8) to give the final lipoyl cofactor. All classical lipoyl synthases (LSs) are radical S-adenosylmethionine (SAM) enzymes, which use an [Fe4S4] cluster to reductively cleave SAM to generate a 5'-deoxyadenosyl 5'-radical. Classical LSs also contain a second [Fe4S4] cluster that serves as the source of both appended sulfur atoms. Recently, a novel pathway for generating the lipoyl cofactor was reported. This pathway replaces the canonical LS with two proteins, LipS1 and LipS2, which act together to catalyze formation of the lipoyl cofactor. In this work, we further characterize LipS1 and LipS2 biochemically and spectroscopically. Although LipS1 and LipS2 were previously annotated as biotin synthases, we show that both proteins, unlike E. coli biotin synthase, contain two [Fe4S4] clusters. We identify the cluster ligands to both iron-sulfur clusters in both proteins and show that LipS2 acts only on an octanoyl-containing substrate, while LipS1 acts only on an 8-mercaptooctanoyl-containing substrate. Therefore, similarly to E. coli biotin synthase and in contrast to E. coli LipA, sulfur attachment takes place initially at the terminal carbon (C8) and then at the C6 methylene carbon.
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This paper describes and evaluates an approximation of the proposed position-changing mechanism of a cerebral palsy wheelchair for children using only one actuator. Only details the functional requirements that allow the change of position: wheelchair mode, standing frame mode, and stretcher mode. To evaluate the mechanism, a video was recorded and evaluated in Kinovea, and MATLAB software to obtain the functional angular range of the backrest reclination and the seat elevation. The scaled prototype has a mean error of 2.58% in comparison with the original design. The results indicate that this mechanism effectively provided compliance with the proposed angles and comfort for the patient.
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Parálisis Cerebral , Silla de Ruedas , Niño , Diseño de Equipo , Humanos , Postura , Posición de PieRESUMEN
BACKGROUND AND OBJECTIVES: Incidence of pancreatic neuroendocrine tumors (pNETS) seems to be rising over the years, with many cases incidentally diagnosed. Surgery and active surveillance are current treatment modalities for small pNETS. We review our institutional series and compare outcomes for small asymptomatic and nonfunctioning tumors. METHODS: This retrospective cohort study included patients with 2 cm or less and well differentiated pNETS at a single Brazilian Cancer Center. From 2002 to 2020, patients received active surveillance or surgery as a treatment strategy. Short and long-term results were compared. RESULTS: Sixty-four patients were included, 41 in surgical strategy and 23 in the active surveillance approach. Baseline group characteristics were comparable. More patients on active surveillance underwent abdominal magnetic resonance imaging (MRI) and had tumors located in the pancreatic head (41% vs. 17%, p = 0.038). Minimally invasive procedure was chosen in 80.1% of the surgical patients. No patient died after surgery. Median follow-up period was 38.6 and 46.4 months for active surveillance and surgery cohorts, respectively. No difference in disease progression rate was observed. CONCLUSION: Both approaches seem to be safe for small pNETs. Long-term outcome and quality of life should be considered when discussing such options with patients.