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This study aimed to investigate the sustainable use of recycled plastics, specifically polypropylene (PP) and high-density polyethylene (HDPE), in the manufacture of geogrids for geotechnical and civil engineering applications. Plastics were collected from a recycling center, specifically targeting containers used for food, cleaning products, and other domestic packaging items. These plastics were sorted according to the Möbius triangle classification system, with HDPE (#2) and PP (#5) being the primary categories of interest. The research methodologically evaluates the mechanical properties of PP/HDPE (0/100, 25/75, 50/50, 75/25 and 100/0% w/w) composites through tensile and flexural tests, exploring various compositions and configurations of geogrids. The results highlight the superiority of pure recycled HDPE processed into 1.3 mm thick laminated yarns and hot air welded for 20 to 30 s, exhibiting a deformation exceeding 60% in comparison to the PP/HDPE composites. Through SolidWorks® Simulation, it was shown that the adoption of a trigonal geogrid geometry optimizes force distribution and tensile strength, significantly improving slope stabilization efficiency. Based on the results obtained, a laboratory-scale prototype geogrid was developed using an extrusion process. The results underscore the importance of careful composite design and yarn configuration selection to achieve the desired mechanical properties and performance in geogrid applications. It emphasizes the potential of recycled plastics as a viable and environmentally friendly solution for stabilizing slopes, contributing to the reduction in plastic waste and promoting sustainable construction practices.
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Tamandua mexicana is an anteater species native from Mexico to Peru. This species is of great evolutionary interest because it belongs to one of the oldest clades of placental mammals in the American continent. This study aimed to describe the origin, insertion, and arterial supply of the intrinsic shoulder and brachial muscles of T. mexicana. We also compared the masses of the functional groups. Gross dissections were performed on both thoracic limbs of 13 cadavers. ANOVA followed by Tukey's test was used for statistical analyses. The subscapularis muscle presents a hiatus to the common tendon of the caput breve of the biceps brachii and coracobrachialis muscles. A variant accessory muscle, the m. articularis humeri lateralis, was found on the lateral surface of the shoulder joint. M. deltoideus pars acromialis has two bellies. The teres major muscle is perforated by the aponeurotic origin of the m. tensor fasciae antebrachii. The triceps brachii has two capita longi. The caput mediale is fused with the m. anconeus medialis. The caput laterale can have an accessory belly as an anatomical variant. Among the functional groups, a significant difference was found between the elbow extensors and flexors, with the latter having the lowest mass. In conclusion, the intrinsic muscles of T. mexicana presented unique features for the species, as well as arrangements in mass distribution that evidence a possible evolutionary convergence among species of the Superorder Xenarthra.
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Evolução Biológica , Músculo Esquelético , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Animais , Ombro/anatomia & histologia , Ombro/fisiologia , Feminino , Masculino , Articulação do Ombro/anatomia & histologia , Articulação do Ombro/fisiologia , Eutérios/anatomia & histologia , Eutérios/fisiologiaRESUMO
The Neotropical otter (Lontra longicaudis) is a mustelid distributed geographically from Mexico to Argentina. Anomalous origins of the aortic arch branches are rarely reported in wild carnivorans. Therefore, this study aimed to report the anomalous branching of the aortic arch in one formaldehyde-fixed specimen of L. longicaudis. The aortic arch provided three branches: the bicarotid trunk and the left and right subclavian arteries. The latter passed dorsally to the esophagus toward the right side without a mark of compression at the esophagus. This is the first report of an anomalous origin of the right subclavian artery in L. longicaudis.
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Lontras , Artéria Subclávia , Animais , Aorta TorácicaRESUMO
Community-based psychosocial support group (CB-PSS) interventions using task-shifting approaches are well suited to provide culturally appropriate services in low- and middle-income countries. However, contextual barriers and facilitators must be considered to tailor interventions effectively, particularly considering the challenges introduced by the COVID-19 pandemic. We explore the barriers, facilitators, and psychosocial changes associated with implementing a CB-PSS group intervention delivered by local lay providers to conflict-affected adults in Quibdó, Colombia, using both in-person and remote modalities. Data were analyzed from 25 individual interviews with participants and a focus group discussion involving staff members, including 7 community psychosocial agent facilitators and 2 mental health professional supervisors. The analysis used a thematic approach grounded in a descriptive phenomenology to explore the lived experiences of participants and staff members during implementation. Participant attendance in the in-person modality was compromised by factors such as competing work and family responsibilities and disruption caused by the COVID-19 pandemic. Participants in the remote modality faced challenges concerning unstable Internet connectivity, recurrent power outages caused by heavy rain, distractions, interruptions, and threats to confidentiality by family and coworkers. Despite these challenges, data revealed key contextual facilitators, including the community-based knowledge of facilitators and integration of traditional practices, such as the comadreo (informal talks and gatherings). Respondents shared that the CB-PSS groups promoted stronger community relationships and created opportunities for participants to exchange peer support, practice leadership skills, develop problem-solving skills based on peers' experiences, and enhance emotional regulation skills. Differences and similarities across in-person and remote modalities are discussed, as are key considerations for practitioners and policymakers.
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COVID-19 , Sistemas de Apoio Psicossocial , Adulto , Humanos , Pandemias , Colômbia , Pesquisa QualitativaRESUMO
The new lymphoma classifications (International Consensus Classification of Mature Lymphoid Neoplasms, and 5th World Health Organization Classification of Lymphoid Neoplasms) include genetics as an integral part of lymphoma diagnosis, allowing better lymphoma subclassification, patient risk stratification, and prediction of treatment response. Lymphomas are characterized by very few recurrent and disease-specific mutations, and most entities have a heterogenous genetic landscape with a long tail of recurrently mutated genes. Most of these occur at low frequencies, reflecting the clinical heterogeneity of lymphomas. Multiple studies have identified genetic markers that improve diagnostics and prognostication, and next-generation sequencing is becoming an essential tool in the clinical laboratory. This review provides a "next-generation sequencing" guide for lymphomas. It discusses the genetic alterations of the most frequent mature lymphoma entities with diagnostic, prognostic, and predictive potential and proposes targeted sequencing panels to detect mutations and copy-number alterations for B- and NK/T-cell lymphomas.
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In this work, the use of DNA-stabilized fluorescent silver nanoclusters for the detection of target pyrimidine-rich DNA sequences by formation of parallel and antiparallel triplex structures is studied by molecular fluorescence spectroscopy. In the case of parallel triplexes, the probe DNA fragments are Watson-Crick stabilized hairpins, and whereas in the case of antiparallel triplexes, the probe fragments are reverse-Hoogsteen clamps. In all cases, the formation of the triplex structures has been assessed by means of polyacrylamide gel electrophoresis, circular dichroism, and molecular fluorescence spectroscopies, as well as multivariate data analysis methods. The results have shown that it is possible the detection of pyrimidine-rich sequences with an acceptable selectivity by using the approach based on the formation of antiparallel triplex structures.
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DNA , Prata , Sequência de Bases , DNA/genética , DNA/química , Pirimidinas , Corantes , Conformação de Ácido Nucleico , Dicroísmo CircularRESUMO
The mechanisms triggering metastasis in pheochromocytoma/paraganglioma are unknown, hindering therapeutic options for patients with metastatic tumors (mPPGL). Herein we show by genomic profiling of a large cohort of mPPGLs that high mutational load, microsatellite instability and somatic copy-number alteration burden are associated with ATRX/TERT alterations and are suitable prognostic markers. Transcriptomic analysis defines the signaling networks involved in the acquisition of metastatic competence and establishes a gene signature related to mPPGLs, highlighting CDK1 as an additional mPPGL marker. Immunogenomics accompanied by immunohistochemistry identifies a heterogeneous ecosystem at the tumor microenvironment level, linked to the genomic subtype and tumor behavior. Specifically, we define a general immunosuppressive microenvironment in mPPGLs, the exception being PD-L1 expressing MAML3-related tumors. Our study reveals canonical markers for risk of metastasis, and suggests the usefulness of including immune parameters in clinical management for PPGL prognostication and identification of patients who might benefit from immunotherapy.
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Neoplasias das Glândulas Suprarrenais , Segunda Neoplasia Primária , Paraganglioma , Feocromocitoma , Humanos , Neoplasias das Glândulas Suprarrenais/genética , Genômica , Paraganglioma/genética , Paraganglioma/imunologia , Feocromocitoma/genética , Feocromocitoma/imunologia , Microambiente Tumoral/genéticaRESUMO
Procyon cancrivorus and Nasua nasua are two procyonids with different evolutionary adaptations to use their thoracic limbs. Therefore, this study aimed to characterize the differences in the brachial plexus between both species. Five P. cancrivorus and five N. nasua cadavers were used to perform this investigation with the permission of the bioethics committee and environmental license. Gross dissections were performed on the cervical, pectoral, and thoracic limb regions to find the origin and distribution of the brachial plexus. The brachial plexus of both species originated in a variant manner from C5-T1, C5-T2, C6-T1, or C6-T2. All brachial plexus nerves were observed and, interestingly, the musculocutaneous sent a communicating branch to the median nerve medially to the axillary artery, forming an ansa axillaris in both species. An ansa pectoralis was also observed medially to the axillary artery. Additionally, in P. cancrivorus, the musculocutaneous nerve innervates the pronator teres and flexor carpi radialis muscles and communicates with the median nerve at the elbow level to continue as a common trunk at the antebrachium. The brachial plexus has differences between both procyonids, although in both species, it could conserve a primitive arrangement present within the infraorder Arctoidea.
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The procyonids (Procyon cancrivorus, Nasua nasua and Potos flavus) are Neotropical carnivorans with the ability to climb trees; however, each one has different locomotor preferences. Thereby, P. flavus is highly arboreal, P. cancrivorus is mainly terrestrial with abilities to swim, and N. nasua is also fossorial. These activities not only require movements of the hands but stabilize the thoracic limb, an action performed by the extrinsic muscles. Besides, former descriptions performed in procyonid species have obsolete terms for these muscles, generating confusion about the comparison among species. Thereby, muscle innervation has also been used to support the evolutionary derivation of the muscles. Therefore, this study aimed to describe the attachments and innervations of these muscles in three procyonids. There were intra- and interspecific anatomical variations in the attachments of all extrinsic thoracic limb muscles. However, based on the innervation, several evolutionary derivations in procyonids could be found, such as: the cleidobrachialis muscle derived from the deltoideus muscle; the atlantoscapularis muscle of P. flavus derived from the serratus ventralis cervicis muscle; the pectoralis transversus muscle derived from the pectoralis profundus and superficiales muscles; and the pectoralis abdominalis muscle derived from the cutaneus trunci muscle. Some functions could be associated with locomotor habits, among them a highly developed pectoralis abdominalis in Nasua for its fossorial habits and the atlantoscapularis in Potos for its arboreal and prehensile habits. Thus, the extrinsic muscles in procyonids have evolved for locomotor preferences, but mainly due to their phylogenetic relationship within the family Procyonidae.
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Procyonidae , Guaxinins , Animais , Filogenia , Músculo Esquelético , Extremidade SuperiorRESUMO
BACKGROUND: The robust brown capuchin monkey (Sapajus apella) is a South American primate with preferences for arboreal locomotion, which requires specific thoracic limb muscle adaptations. The present investigation studied the gross anatomy of the extrinsic and intrinsic scapular and brachial muscles. METHODS: Gross dissections were performed in both thoracic limbs of four formaldehyde-fixed specimens. RESULTS: Three rhomboideus muscles were present (capitis, cervicis, and thoracis). The trapezius muscle was divided into two parts (cervicis and thoracis). The pectoralis abdominalis and omotransversarius muscles were present. The anconeus muscle was found as an individual muscle or fused to the caput mediale of the triceps brachii muscle. The brachialis muscle had among one and two heads. The anconeus epitrochlearis was absent. CONCLUSION: These muscles of Sapajus apella are adapted for arboreal locomotion and some terrestrial habits, since these have many similarities with other primates with a similar locomotor patterns.
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Músculo Esquelético , Sapajus apella , Animais , Músculo Esquelético/anatomia & histologia , Membro Anterior , Locomoção/fisiologia , PrimatasRESUMO
Introducción: la Organización Mundial de la Salud considera a las lesiones accidentales o lesiones no intencionales (LNI) como un problema de salud pública por su efecto sobre la discapacidad y mortalidad en la población general. Objetivo: presentar y analizar los datos de LNI y muertes accidentales registrados por el Instituto Nacional de Medicina Legal y Ciencias Forenses en el departamento de Antioquia, durante los años 2016 y 2017. Métodos: estudio descriptivo basado en la información recolectada por el Instituto Nacional de Medicina Legal y Ciencias Forenses. Se calcula ron las tasas de lesionados y muertes por 100.000 habitantes/año y el análisis estadístico se realizó con el paquete estadístico SPSS® versión 24.0. Resultados: durante 2016 y 2017 se registró una tasa de morbilidad de LNI de 7,86 y 7,21 casos por 100.000 habitantes, respectivamente, similar a la del promedio nacional. Fue mayor el número de casos en hombres que en mujeres, principalmente entre los 18 y los 34 años. La tasa de mortalidad reportada fue de 10,10 y 11,05 por cada 100.000 habitantes para el mismo periodo. Las LNI fueron más frecuentes en personas con bajo nivel educativo, del área urbana, y el mecanismo traumático más frecuente fue el contundente. Conclusiones: este estudio evidencia disminución en las tasas de LNI y aumento de la mortalidad accidental en Antioquia, comparada con años anteriores. Dicho comportamiento es diferente a lo reportado por la literatura internacional. Se requieren investigaciones que analicen otras fuentes generadoras de información acerca de las LNI, con la finalidad de estimar con mayor precisión la ocurrencia del fenómeno y sus variables asociadas.
Background: The World Health Organization con siders unintentional injuries (UI) as an international public health problem, due to their effect on disability and mortality in the general population. Objective: To present and analyze the data on UI and accidental death collected by the National Institute of Legal Medicine and Forensic Sciences in the Department of Antioquia, Colombia, between 2016 and 2017. Methods: Descriptive study based on the information collected by the National Institute of Legal Medicine and Forensic Sciences. The rates of injuries and deaths per 100,000 inhabitants / year were calculated, and the statistical analysis was made using SPSS® version 24.0. Results: In the years 2016 and 2017, there was a morbidity rate of UI of 7.86 and 7.21 cases per 100,000 inhabitants, respectively, similar to the national average. The number of cases was greater in men than in women, mainly between 18 and 34 years of age. The reported accidental mortality rate was 10.10 and 11.05 per 100,000 inhabitants for the years 2016 and 2017, respectively. The UI were more frequent in people with low educational level, from the urban area, and the most frequent traumatic mechanism was the blunt one. Conclusions: This study shows a reduction in the rates of UI and an increase of the rates of accidental death in Antioquia compared to the previous years. This trend is different to the previously reported on international literature. More studies analyzing other sources of information on variables like UI are needed in this field, in order to precisely estimate the occurrence of this event and its associated variables.
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Humanos , Masculino , Feminino , ColômbiaRESUMO
Based on most neuroanatomical descriptions, the anterior spinal artery (ASA) originates from two small vessels of the vertebral arteries, which are anastomosed just before forming the basilar artery. This study aimed to determine and quantify the possible variants of the origin of the ASA and its trajectory in samples of human brain stems. Male brain stems with the superior portion of the spinal cord until myelomera C3 of 23 adult human, and no evident morphological alterations were selected. The brain stems were collected for three years and fixed in a 10% formalin solution at the Anatomy Laboratory of the Universidad de Caldas (Colombia). Five samples (21.7%) had variations in the origin and trajectory of the anterior spinal artery. The variations in the origin of the ASA could generate morphofunctional advantages instead of leading to complications. That is the case when there are two anterior spinal arteries since it would increase tissue perfusion, thus protecting part of the spinal cord from ischemic pathologies. It is essential to consider the variations that may exist in the supply of the anterior region of the spinal cord for clinical and surgical assessments due to variations in its supplied territory.
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The kinkajou (Potos flavus) is a carnivoran adapted for arboreal quadrupedal locomotion along with a prehensile tail. The thoracic limb bones and muscles of this species have been studied, but the knowledge about its nerves is still scarce. This knowledge is necessary to perform several veterinary procedures, and to review the differences among carnivoran species. Thus, the objective of this study was to describe the origin and distribution of the brachial plexus in Potos flavus. Thereby, both brachial plexuses of five specimens were dissected (10). Seven plexuses originated from C6-T2 (70%), whilst three plexuses originated from C5-T2 (30%). Additionally, C6 and C7 formed two cranial trunks, and C8, T1 and T2 formed two caudal trunks. All nerves from the brachial plexus that have been reported in carnivorans were successfully located. In addition, we found one nerve reaching the teres major muscle originating directly from the brachial plexus and not from the axillary nerve as reported in other carnivorans. The brachiocephalic nerve was found partially innervating the cleidobrachialis muscle (50%), but this muscle always was innervated by the axillary nerve. Moreover, one to three subscapular nerves were found, and the musculocutaneous nerve formed two communicating branches (proximal and distal) to the median nerve. However, the distal communicating branch of the musculocutaneous nerve was absent in two specimens (40%). In conclusion, the brachial plexus of P. flavus was differentiated mainly with other carnivorans by a higher contribution from T2, formations of trunks, and one independent nerve to the teres major muscle.
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Evolução Biológica , Plexo Braquial , Procyonidae , Animais , Plexo Braquial/anatomia & histologia , Membro Anterior/inervação , Nervo Mediano , Nervo Musculocutâneo , Procyonidae/anatomia & histologia , Ombro/inervaçãoRESUMO
The kinkajou (Potos flavus) is a carnivoran that has special morphological adaptations in its thoracic limbs to climb threes and handling food. This study aimed to describe the craniolateral muscles of the antebrachium in P. flavus. Five specimens were used. The extensor carpi radialis longus and brevis were seen as two separate muscles. The extensor carpi ulnaris muscle can present two bellies with different insertions. An extensor digit III muscle was found. The P. flavus has anatomical variants on the craniolateral antebrachial muscles that were previously reported in other procyonids. Thus, those variants are phylogenetically related within the family Procyonidae, except the doubled bellies of the extensor carpi ulnaris muscle which is exclusive of P. flavus.
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Procyonidae , Variação Anatômica , Animais , Antebraço/anatomia & histologia , Músculo Esquelético/anatomia & histologiaRESUMO
Tamandua is a neotropical mammal genus that belongs to the superorder Xenarthra. The thoracic limbs of Tamandua have anatomical adaptations that widely differ from other mammals, and there are frequently specimens in wildlife care centers with traumas in their limbs. However, there are few studies describing the radiographic and morphometric anatomy of the humerus in Tamandua, or describing partially the bone reliefs. Thus, the main objective of this study was to describe the characteristics of the humerus of Tamandua mexicana based on gross dissections, radiographies and measurements comparing with other studies in the three Vermilingua genera, and establishing more suitable terminology. Twelve thoracic limbs of six death specimens of Tamandua mexicana were analyzed. The bone reliefs, ligaments, muscles and neurovascular structures related to the humerus were identified, and the suitable terminology to the humerus of Tamandua was established. Morphometric measurements of each bone relief were taken, and the data were statistically analyzed with the Wilcoxon non-parametric test for functional proposes. The humerus of Tamandua has anatomical characteristics mainly to offer greater areas to the muscles that act on the shoulder flexion and hand movements. Even the articular reliefs are lesser than the adjacent non-articular reliefs, the muscles and ligaments are the anatomical structures that give more stabilization to the shoulder and elbow joints. The deltosupracondylar ligament can be partially ossified in older adult specimens, and neurovascular structures pass through the supracondylar foramen. These anatomical characteristics must be accounted for in the radiological diagnosis and surgical approaches.
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Vermilingua , Xenarthra , Animais , Membro Anterior , Úmero/diagnóstico por imagem , Extremidade SuperiorRESUMO
Interthalamic adhesion is an inconstant part of the human diencephalic neuroanatomy, which some histological studies have indicated it is a gray commissure and others a white commissure. Its presence has been associated with alterations in health status, including schizophrenia, psychotic states, and hydrocephalus. Thirty-one fresh human brains were evaluated randomly, to determine the presence of interthalamic adhesion and its histological composition, by way of lamina terminalis puncture of the third ventricle. Photographic records were taken and histological processes was performed by hematoxylin-eosin staining, in the case of the existence of the adhesion. It was found that 51.71% did present interthalamic adhesion, and on histological examination, no neuron bodies were found in the median part, which implies that does not correspond to a gray commissure, but interthalamic adhesion in humans is variable, with a predominance of glial cells. There is no gray commissure in human interthalamic adhesions.
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Splenic marginal zone B-cell lymphoma (SMZL) is a heterogeneous clinico-biological entity. The clinical course is variable, multiple genes are mutated with no unifying mechanism, and essential regulatory pathways and surrounding microenvironments are diverse. We sought to clarify the heterogeneity of SMZL by resolving different subgroups and their underlying genomic abnormalities, pathway signatures, and microenvironment compositions to uncover biomarkers and therapeutic vulnerabilities. We studied 303 SMZL spleen samples collected through the IELSG46 multicenter international study (NCT02945319) by using a multiplatform approach. We carried out genetic and phenotypic analyses, defined self-organized signatures, validated the findings in independent primary tumor metadata and in genetically modified mouse models, and determined correlations with outcome data. We identified 2 prominent genetic clusters in SMZL, termed NNK (58% of cases, harboring NF-κB, NOTCH, and KLF2 modules) and DMT (32% of cases, with DNA-damage response, MAPK, and TLR modules). Genetic aberrations in multiple genes as well as cytogenetic and immunogenetic features distinguished NNK- from DMT-SMZLs. These genetic clusters not only have distinct underpinning biology, as judged by differences in gene-expression signatures, but also different outcomes, with inferior survival in NNK-SMZLs. Digital cytometry and in situ profiling segregated 2 basic types of SMZL immune microenvironments termed immune-suppressive SMZL (50% of cases, associated with inflammatory cells and immune checkpoint activation) and immune-silent SMZL (50% of cases, associated with an immune-excluded phenotype) with distinct mutational and clinical connotations. In summary, we propose a nosology of SMZL that can implement its classification and also aid in the development of rationally targeted treatments.
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Linfoma de Zona Marginal Tipo Células B , Neoplasias Esplênicas , Idoso , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Aberrações Cromossômicas , Imunofenotipagem , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/genética , Família Multigênica , Mutação , Baço/patologia , Neoplasias Esplênicas/diagnóstico , Neoplasias Esplênicas/genética , Transcriptoma , Microambiente TumoralRESUMO
Epidemiological studies have demonstrated the association between hepatitis B virus (HBV) infection and B-cell non-Hodgkin lymphoma (NHL), mainly for diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). We studied a cohort of 121 patients with FL for HBV infection status, clinical features, and gene mutational profile. Anti-HBc was detectable in 16 patients (13.2%), although all had undetectable HBV DNA. Anti-HBcore+ (anti-HBc+) cases presented with older age at diagnosis than anti-HBc- cases (68.1 vs 57.2 years; P = .007) and higher ß2-microglobulin (56.3% vs 28.9%; P = .04). All patients included in the study fulfilled criteria for treatment and received therapy with rituximab or rituximab-containing chemotherapy. There were no episodes of HBV reactivation or HBV hepatitis during treatment and/or maintenance. Remarkably, anti-HBc+ patients had significantly lower 10-year progression-free survival (PFS; 12.9% vs 58.3%; P < .0001) and overall survival (OS; 22.0% vs 86.2%; P < .0001), that remained at multivariate analysis. Gene mutational profiling of all cases showed that anti-HBc+ cases had higher incidence of ARID1A mutations and absence of EP300 mutations, 2 key epigenetic regulators in FL. Overall, our study shows that FL patients with resolved HBV infection have a worse outcome independently of other well-known clinical risk factors and a distinct gene mutational profile.
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Linfoma Folicular , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígenos de Superfície da Hepatite B/uso terapêutico , Vírus da Hepatite B/genética , Humanos , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/genética , MutaçãoRESUMO
The kinkajou (Potos flavus) and crab-eating raccoon (Procyon cancrivorus) are carnivores belonging to the family Procyonidae, but both species are characterized by different types of locomotion. Differences can be found in the adaptations that these two species present in the forearm muscles, such as the flexor digitorum superficialis (FDS), palmaris longus (PL) and interflexorii (IF), which have been described confusingly in previous studies. Therefore, the aim of this study was to describe these muscles in both species together with their innervations to carry out an evolutionary and terminological analysis among carnivorans. Both thoracic limbs were dissected from five P. flavus and three P. cancrivorus that had died of natural causes in Wildlife Care Centers. Two PL muscles (m. palmaris longus lateralis, PLL, and m. palmaris longus medialis, PLM) were found in P. flavus, and the IF were the only superficial flexors of the digits, whereas P. cancrivorus presented the IF and two bellies homologous to the two PLs of P. flavus, where the homologous belly of the PLM sent tendons to digits II-IV. Therefore, it was considered as the FDS due to its similarity to other carnivorans, and the lateral belly is the only PL present in P. cancrivorus. The topology, attachments and innervation of these muscles in P. flavus and P. cancrivorus allowed homologies to be established, hypothesizing their evolutionary derivation from the FDS. It also allowed the differences among PL, FDS and IF muscles to be described, concluding that most carnivorans do not have a PL.
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Braquiúros , Antebraço , Animais , Mãos , Músculo Esquelético , GuaxininsRESUMO
The northern tamandua (Tamandua mexicana) is a neotropical mammal of the order Pilosa, suborder Vermilingua, and family Myrmecophagidae. This species has anatomical and functional adaptations in its forelimb for semiarboreal quadrupedal locomotion. Several studies have reported that the medial head of the triceps brachii and flexor digitorum profundus muscles are fused in species belonging to the family Myrmecophagidae. However, there is no reference to the innervation in these. The triceps brachii muscle is commonly innervated by the radial nerve and the flexor digitorum profundus muscle by the ulnar and median nerves. This study aims to describe the gross anatomy of the flexor digitorum profundus muscle in Tamandua mexicana with respect to the shape, origin, insertion, innervation, and arterial supply. Both forelimbs of nine specimens were used, which were dissected from superficial to deep layers. The formalin-fixed caudomedial forearm muscles were weighed, and the weight percentages of individual forearm muscle specimens were calculated. The flexor digitorum profundus had the highest weight among the forearm muscles and consisted of five heads (three humerals, one radial, and one ulnar). These heads were innervated by median and ulnar nerves; therefore, based on the innervation pattern, we concluded that the medial head of the triceps brachii muscle is not fused with the flexor digitorum profundus. Therefore, the flexor digitorum profundus muscle is highly developed in Tamandua and occupies the caudal part of the arm and forearm, which is an evolutionary adaptation that could have occurred during evolution from the common ancestor of Tamandua and Myrmecophaga.