RESUMO
Gap junction channels, composed of connexins, allow direct cell-to-cell communication. Connexin 43 (Cx43; also known as GJA1) is widely expressed in tissues, including the epidermis. In a previous study of human papillomavirus-positive cervical epithelial tumour cells, we identified Cx43 as a binding partner of the human homologue of Drosophila Discs large (Dlg1; also known as SAP97). Dlg1 is a member of the membrane associated-guanylate kinase (MAGUK) scaffolding protein family, which is known to control cell shape and polarity. Here, we show that Cx43 also interacts with Dlg1 in uninfected keratinocytes in vitro and in keratinocytes, dermal cells and adipocytes in normal human epidermis in vivo. Depletion of Dlg1 in keratinocytes did not alter Cx43 transcription but was associated with a reduction in Cx43 protein levels. Reduced Dlg1 levels in keratinocytes resulted in a reduction in Cx43 at the plasma membrane with a concomitant reduction in gap junctional intercellular communication and relocation of Cx43 to the Golgi compartment. Our data suggest a key role for Dlg1 in maintaining Cx43 at the plasma membrane in keratinocytes.
Assuntos
Conexina 43 , Proteína 1 Homóloga a Discs-Large , Queratinócitos , Humanos , Comunicação Celular , Membrana Celular/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Junções Comunicantes/metabolismo , Guanilato Quinases/metabolismo , Queratinócitos/metabolismo , Proteína 1 Homóloga a Discs-Large/genética , Proteína 1 Homóloga a Discs-Large/metabolismoRESUMO
The Australian Synchrotron Imaging and Medical Beamline (IMBL) uses a superconducting multipole wiggler (SCMPW) source, dual crystal Laue monochromator and 135â m propagation distance to enable imaging and computed tomography (CT) studies of large samples with mono-energetic radiation. This study aimed to quantify two methods for CT dose reduction: wiggler source operation at reduced magnetic field strength, and beam modulation with spatial filters placed upstream from the sample. Transmission measurements with copper were used to indirectly quantify the influence of third harmonic radiation. Operation at lower wiggler magnetic field strength reduces dose rates by an order of magnitude, and suppresses the influence of harmonic radiation, which is of significance near 30â keV. Beam shaping filters modulate the incident beam profile for near constant transmitted signal, and offer protection to radio-sensitive surface organs: the eye lens, thyroid and female breast. Their effect is to reduce the peripheral dose and the dose to the scanned volume by about 10% for biological samples of 35-50â mm diameter and by 20-30% for samples of up to 160â mm diameter. CT dosimetry results are presented as in-air measurements that are specific to the IMBL, and as ratios to in-air measurements that may be applied to other beamlines. As CT dose calculators for small animals are yet to be developed, results presented here and in a previous study may be used to estimate absorbed dose to organs near the surface and the isocentre.
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Campos Magnéticos , Radiometria , Síncrotrons , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Radiometria/métodos , Humanos , Feminino , Doses de Radiação , Cristalino/efeitos da radiação , Glândula TireoideRESUMO
The pandemic spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiological agent of Coronavirus Disease 2019 (COVID-19), represents an ongoing international health crisis. A key symptom of SARS-CoV-2 infection is the onset of fever, with a hyperthermic temperature range of 38 to 41°C. Fever is an evolutionarily conserved host response to microbial infection that can influence the outcome of viral pathogenicity and regulation of host innate and adaptive immune responses. However, it remains to be determined what effect elevated temperature has on SARS-CoV-2 replication. Utilizing a three-dimensional (3D) air-liquid interface (ALI) model that closely mimics the natural tissue physiology of SARS-CoV-2 infection in the respiratory airway, we identify tissue temperature to play an important role in the regulation of SARS-CoV-2 infection. Respiratory tissue incubated at 40°C remained permissive to SARS-CoV-2 entry but refractory to viral transcription, leading to significantly reduced levels of viral RNA replication and apical shedding of infectious virus. We identify tissue temperature to play an important role in the differential regulation of epithelial host responses to SARS-CoV-2 infection that impact upon multiple pathways, including intracellular immune regulation, without disruption to general transcription or epithelium integrity. We present the first evidence that febrile temperatures associated with COVID-19 inhibit SARS-CoV-2 replication in respiratory epithelia. Our data identify an important role for tissue temperature in the epithelial restriction of SARS-CoV-2 independently of canonical interferon (IFN)-mediated antiviral immune defenses.
Assuntos
Células Epiteliais/imunologia , Temperatura Alta , Imunidade Inata/imunologia , Interferons/imunologia , Mucosa Respiratória/imunologia , SARS-CoV-2/imunologia , Replicação Viral/imunologia , Adolescente , Animais , COVID-19/genética , COVID-19/imunologia , COVID-19/virologia , Chlorocebus aethiops , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Feminino , Perfilação da Expressão Gênica/métodos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/genética , Interferons/genética , Interferons/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , RNA-Seq/métodos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Técnicas de Cultura de Tecidos , Células Vero , Replicação Viral/genética , Replicação Viral/fisiologiaRESUMO
The study of humpback whale song using passive acoustic monitoring devices requires bioacousticians to manually review hours of audio recordings to annotate the signals. To vastly reduce the time of manual annotation through automation, a machine learning model was developed. Convolutional neural networks have made major advances in the previous decade, leading to a wide range of applications, including the detection of frequency modulated vocalizations by cetaceans. A large dataset of over 60 000 audio segments of 4 s length is collected from the North Atlantic and used to fine-tune an existing model for humpback whale song detection in the North Pacific (see Allen, Harvey, Harrell, Jansen, Merkens, Wall, Cattiau, and Oleson (2021). Front. Mar. Sci. 8, 607321). Furthermore, different data augmentation techniques (time-shift, noise augmentation, and masking) are used to artificially increase the variability within the training set. Retraining and augmentation yield F-score values of 0.88 on context window basis and 0.89 on hourly basis with false positive rates of 0.05 on context window basis and 0.01 on hourly basis. If necessary, usage and retraining of the existing model is made convenient by a framework (AcoDet, acoustic detector) built during this project. Combining the tools provided by this framework could save researchers hours of manual annotation time and, thus, accelerate their research.
Assuntos
Jubarte , Animais , Vocalização Animal , Espectrografia do Som , Fatores de Tempo , Estações do Ano , AcústicaRESUMO
Combining ecological resilience theory with a phenomenological epistemology, we explored experiential, social, and cultural factors mediating resilience-building with participants from a village destroyed by the 2018 Fuego volcanic eruption in Guatemala. The purpose of the study is to find out what strategies displaced families and communities employ for living through the aftermath of a volcano eruption and for building psychological resilience. We conducted semistructured interviews with nine survivors of the Fuego eruption, now relocated and coping with the loss of community and family members killed in the disaster. Interpretive phenomenological analysis was used to analyze transcripts. The analysis produced four main themes: (i) individual and collective challenges, (ii) social support and protection, (iii) faith and culturally endorsed belief, and (iv) looking to the future. As well as learning more about how a community faced challenges presented by a volcano eruption, the current study has a degree of transferability, with implications for understanding how other communities experience and cope with such events.
Assuntos
Adaptação Psicológica , Resiliência Psicológica , Apoio Social , Erupções Vulcânicas , Humanos , Guatemala , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Sobreviventes/psicologia , Desastres , Entrevistas como Assunto , IdosoRESUMO
OBJECTIVE: The aim of this study was to compare patient-reported urinary, bowel, and sexual functioning of ALaCaRT Trial participants randomized to open or laparoscopic surgery for rectal cancer. SUMMARY BACKGROUND DATA: The primary endpoint, noninferiority of laparoscopic surgical resection adequacy, was not established. METHODS: Participants completed QLQ-CR29 at baseline, 3, and 12 months post-surgery. Additionally, women completed Rosen's Female Sexual Functioning Index (FSFI). Men completed the International Index of Erectile Function (IIEF) and QLQ-PR25. We compared the proportions of participants in each group who experienced moderate/severe symptoms/dysfunction at each time-point and compared mean difference scores from baseline to 12 months between groups. All analyses were intention-to-treat. Sexual functioning analyses included only the participants who expressed sexual interest at baseline. RESULTS: Baseline PRO compliance of 475 randomized participants was 88%. At 12 months, a lower proportion of open surgery participants experienced moderate-severe fecal incontinence and sore skin, compared to Laparoscopic participants, and a lower proportion of men randomized to open surgery experienced moderate-severe urinary symptoms. There were no differences at 3 months for bowel or urinary symptoms. Sexual functioning among sexually interested participants was similar between groups at 3 and 12 months; however, a lower proportion of women reported moderate to severe sexual dissatisfaction at 3 months in the open as compared to the laparoscopic group, (Rebecca.mercieca@sydney.edu.au., 95% CI 0.03-0.39). DISCUSSION: Despite the slightly lower proportions of open surgery participants self-reporting moderate-severe symptoms for 3 of 16 urinary/bowel domains, and lack of differences in sexual domains, it remains difficult to recommend one surgical approach over another for rectal resection.
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Laparoscopia , Protectomia , Neoplasias Retais , Masculino , Feminino , Humanos , Neoplasias Retais/cirurgia , Reto/cirurgia , Protectomia/efeitos adversos , Medidas de Resultados Relatados pelo PacienteRESUMO
BACKGROUND: Laparoscopic-assisted surgery for rectal cancer is widely used, however the healthcare costs are thought to be higher than for open resection. This secondary endpoint analysis of a randomized controlled trial aimed to evaluate total healthcare costs of laparoscopic-assisted surgery compared with open resection for rectal cancer over a 12-month period. METHODS: Patients in the Australasian Laparoscopic Cancer of the Rectum Trial (ALaCaRT) were included in a prospective costing analysis. All healthcare use for the index surgery and hospital admission, readmissions, and follow-up care over 12 months were included. Unit costs were valued in Australian dollars (AUD$) using scheduled Medicare fees and hospital cost weights. The primary outcome was mean per patient cost. Non-parametric bootstrapping with 10,000 replications was undertaken for robustness checks. RESULTS: Data from 468 patients indicated that the laparoscopic-assisted surgical procedure incurred a mean cost of AUD$4542 (standard deviation [SD] AUD$1050)-AUD$521 higher than the open procedure mean cost of AUD$4021 (SD AUD$804) due to longer operative time and involvement of more costly equipment (95% confidence interval [CI] AUD$354-AUD$692). At 12 months, the average cost for the laparoscopic-assisted and open groups was AUD$43,288 (SD AUD$40,883) and AUD$45,384 (SD AUD$38,659), respectively, due to the shorter subsequent hospital stays. No overall significant cost difference between groups was found (95% CI -AUD$9358 to AUD$5003). One-way sensitivity analyses confirmed the robustness of the results. CONCLUSION: While initially higher, the costs of laparoscopic-assisted surgery for rectal cancer were similar to open resection at 12 months. Clinicians may choose a surgical approach based on clinical need. TRIAL REGISTRATION: The Australasian Gastro-Intestinal Trials Group (AGITG) was the legal sponsor and trial coordination was performed by the NHMRC Clinical Trials Centre. The trial was registered with the Australian and New Zealand Clinical Trial Registry (ACTRN12609000663257).
Assuntos
Laparoscopia , Neoplasias Retais , Idoso , Austrália , Custos de Cuidados de Saúde , Humanos , Programas Nacionais de Saúde , Estudos Prospectivos , Neoplasias Retais/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Low anterior resection syndrome has a significant impact on the quality of life in rectal cancer survivors. Previous studies comparing laparoscopic to open rectal resection have neglected bowel function outcomes. OBJECTIVE: This study aimed to assess whether there is a difference in the functional outcome between patients undergoing laparoscopic versus open resection for rectal adenocarcinoma. DESIGN: Cross-sectional prevalence of low anterior resection syndrome was assessed in a secondary analysis of the multicenter phase 3 randomized clinical trial, Australasian Laparoscopic Cancer of the Rectum Trial (ACTRN12609000663257). SETTING: There were 7 study subsites across New Zealand and Australia. PATIENTS: Participants were adults with rectal cancer who underwent anterior resection and had bowel continuity. MAIN OUTCOME MEASURES: Postoperative bowel function was evaluated using the validated low anterior resection syndrome score and Bowel Function Instrument. RESULTS: The Australasian Laparoscopic Cancer of the Rectum Trial randomized 475 patients with T1-T3 rectal adenocarcinoma less than 15 cm from the anal verge. A total of 257 participants were eligible for, and invited to, participate in additional follow-up; 163 (63%) completed functional follow-up. Overall cross-sectional prevalence of major low anterior resection syndrome was 49% (minor low anterior resection syndrome 27%). There were no differences in median overall Bowel Function Instrument score nor low anterior resection syndrome score between participants undergoing laparoscopic versus open surgery (66 vs 67, p = 0.52; 31 vs 27, p = 0.24) at a median follow-up of 69 months. LIMITATIONS: The major limitations are a result of conducting a secondary analysis; the likelihood of an insufficient sample size to detect a difference in prevalence between the groups and the possibility of selection bias as a subset of the randomized population was analyzed. CONCLUSIONS: Bowel dysfunction affects a majority of rectal cancer patients for a significant time after the operation. In this secondary analysis of a randomized trial, surgical approach does not appear to influence the likelihood or severity of low anterior resection syndrome. See Video Abstract at http://links.lww.com/DCR/B794. RESULTADO FUNCIONAL DE LA RESECCIN ASISTIDA POR LAPAROSCOPIA VERSUS RESECCIN ABIERTA EN CNCER DE RECTO ANLISIS SECUNDARIO DEL ESTUDIO DE CNCER DE RECTO LAPAROSCPICO DE AUSTRALASIA: ANTECEDENTES:El síndrome de resección anterior baja tiene un impacto significativo en la calidad de vida de los supervivientes de cáncer de recto. Los estudios anteriores que compararon la resección rectal laparoscópica con la abierta no han presentado resultados de la función intestinal.OBJETIVO:Evaluar si existe una diferencia en el resultado funcional entre los pacientes sometidos a resección laparoscópica versus resección abierta por adenocarcinoma de recto.DISEÑO:La prevalencia transversal del síndrome de resección anterior baja se evaluó en un análisis secundario del ensayo clínico aleatorizado multicéntrico de fase 3, Estudio Sobre el Cáncer de Recto Laparoscópico de Australasia (Australasian Laparoscopic Cancer of the Rectum Trial, ACTRN12609000663257).AJUSTE:Siete subsitios de estudio en Nueva Zelanda y Australia.PACIENTES:Los participantes eran adultos con cáncer de recto que se sometieron a resección anterior con anastomosis.PRINCIPALES MEDIDAS DE RESULTADO:La función intestinal posoperatoria se evaluó utilizando el previamente validado puntaje LARS y el Instrumento de Función Intestinal.RESULTADOS:El Estudio Sobre el Cáncer de Recto Laparoscópico de Australasia asignó al azar a 475 pacientes con adenocarcinoma rectal T1-T3 a menos de 15 cm del borde anal. 257 participantes fueron elegibles e invitados a participar en un seguimiento adicional. 163 (63%) completaron el seguimiento funcional. La prevalencia transversal general de LARS mayor fue del 49% (LARS menor 27%). No hubo diferencias en la puntuación media general del Instrumento de Función Intestinal ni en la puntuación LARS entre los participantes sometidos a cirugía laparoscópica versus cirugía abierta (66 frente a 67, p = 0,52; 31 frente a 27, p = 0,24) en una mediana de seguimiento de 69 meses.LIMITACIONES:Las principales limitaciones son el resultado de realizar un análisis secundario; se analizó la probabilidad de un tamaño de muestra insuficiente para detectar una diferencia en la prevalencia entre los grupos y la posibilidad de sesgo de selección como un subconjunto de la población aleatorizada.CONCLUSIONES:La disfunción intestinal afecta a la mayoría de los pacientes con cáncer de recto durante un tiempo significativo después de la operación. En este análisis secundario de un ensayo aleatorizado, el abordaje quirúrgico no parece influir en la probabilidad o gravedad del síndrome de resección anterior baja. Consulte Video Resumen en http://links.lww.com/DCR/B794. (Traducción-Dr. Felipe Bellolio).
Assuntos
Adenocarcinoma , Laparoscopia , Neoplasias Retais , Adenocarcinoma/cirurgia , Adulto , Estudos Transversais , Humanos , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Qualidade de Vida , Neoplasias Retais/diagnóstico , Neoplasias Retais/cirurgia , SíndromeRESUMO
BACKGROUND: Manual dexterity and visual-spatial ability are considered key to the development of superior laparoscopic skills. Nevertheless, these abilities do not reliably explain all the variance found in the technical performance of surgical trainees. Consequently, we must look beyond these abilities to improve our understanding of laparoscopic skills and to better identify/develop surgical potential earlier on. PURPOSE: To assess the individual and collective impact of physical, cognitive, visual, and psychological variables on performance during and after basic simulation-based laparoscopic skills training. METHOD: Thirty-four medical students (laparoscopic novices) completed a proficiency-based laparoscopic skills training program (using either a 2D or 3D viewing mode). This was followed by one testing session, a follow-up testing session with new (yet similar) tasks, and a series of physical, cognitive, visual, and psychological measures. RESULTS: The statistical models that best predicted variance in training performance metrics included four variables: viewing mode (2D vs 3D), psychological flexibility, perceived task demands, and manual dexterity (bimanual). In subsequent testing, a model that included viewing mode and manual dexterity (assembly) best predicted performance on the pre-practiced tasks. However, for a highly novel, spatially complex laparoscopic task, performance was best predicted by a model that comprised viewing mode, visual-spatial ability, and perceived task demands. At follow-up, manual dexterity (assembly) alone was the best predictor of performance on new (yet similar) tasks. CONCLUSION: By focussing exclusively on physical/cognitive abilities, we may overlook other important predictors of surgical performance (e.g. psychological variables). The present findings suggest that laparoscopic performance may be more accurately explained through the combined effects of physical, cognitive, visual, and psychological variables. Further, the results suggest that the predictors may change with both task demands and the development of the trainee. This study highlights the key role of psychological skills in overcoming initial training challenges, with far-reaching implications for practice.
Assuntos
Laparoscopia , Treinamento por Simulação , Estudantes de Medicina , Aptidão , Competência Clínica , Humanos , Laparoscopia/educaçãoRESUMO
BACKGROUND: The objective of this study was to create the Canadian Food Environment Dataset (Can-FED) and to demonstrate its validity. DATA AND METHODS: Food outlet data were extracted from Statistics Canada's Business Register (BR) in 2018. Retail food environment access measures (both absolute and relative measures) were calculated using network buffers around the centroid of 56,589 dissemination areas in Canada. A k-medians clustering approach was used to create categorical food environment variables that were easy to use and amenable to dissemination. Validity of the measures was assessed by comparing the food environment measures from Can-FED with measures created using Enhanced Points of Interest data by DMTI Spatial Inc. and data from a municipal health inspection list. Validity was also assessed by calculating the geographic variability in food environments across census metropolitan areas (CMAs) and assessing associations between CMA-level food environments and CMA-level health indicators. RESULTS: Two versions of Can-FED were created: a researcher file that must be accessed within a secure Statistics Canada environment and a general-use file available online. Agreement between Can-FED food environment measures and those derived from a proprietary dataset and a municipal health inspection list ranged from rs=0.28 for convenience store density and rs=0.53 for restaurant density. At the CMA level, there is wide geographic variation in the food environment with evidence of patterning by health indicators. INTERPRETATION: Can-FED is a valid and accessible dataset of pan-Canadian food environment measures that was created from the BR, a data source that has not been explored fully for health research.
Assuntos
Alimentos , Características de Residência , Canadá , Comércio , Humanos , RestaurantesRESUMO
ABSTRACT: ter Beek, F, Jokumsen, PS, Sloth, BN, Thomas Stevenson, AJ, and Larsen, RG. Ischemic preconditioning attenuates rating of perceived exertion but does not improve maximal oxygen consumption or maximal power output. J Strength Cond Res 36(9): 2479-2485, 2022-Brief consecutive periods of limb ischemia and reperfusion, known as ischemic preconditioning (IPC), have been reported to increase maximal power output (MPO) during cycling. However, the underlying mechanisms are unclear. Therefore, the purpose of the study was to investigate the effects of IPC on MPO, maximal oxygen consumption (VÌ o2 max), muscle oxygenation, and rating of perceived exertion (RPE) during an incremental cycling test. Fourteen healthy young men participated in this double-blinded, randomized crossover study, involving IPC (250 mm Hg; four 5-minute cycles of ischemia) and sham (20 mm Hg) treatment followed by an incremental cycling test to exhaustion. During the cycling test, VÌ o2 , RPE, heart rate (HR), blood lactate (BL), and muscle oxygenation and deoxygenation (near-infrared spectroscopy) were measured. MPO, VÌ o2 max, HRmax, and muscle deoxygenation did not change with IPC (all p -values > 0.13). Furthermore, IPC had no significant effect on VÌ o2 , HR, or muscle oxygenation during the incremental cycling test (all p -values > 0.18). However, IPC attenuated RPE during cycling at 210 W (IPC: median 17.0 [interquartile range 15.3-19.0]; sham: 17.5 [17.0-19.0]; p = 0.007) and 245 W (IPC: 18.0 [17.0-18.8]; sham: 19.0 [18.0-19.8]; p = 0.011). A single session of IPC did not improve MPO, VÌ o2 max, or measures of oxygen consumption during the cycling test. However, IPC lowered RPE at 210 and 245 W, suggesting that IPC may attenuate the perception of effort at higher submaximal exercise intensities.
Assuntos
Precondicionamento Isquêmico , Esforço Físico , Estudos Cross-Over , Teste de Esforço/métodos , Humanos , Precondicionamento Isquêmico/métodos , Masculino , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologiaRESUMO
OBJECTIVE: To investigate the frequency, nature, and severity of intraoperative adverse near miss events within advanced laparoscopic surgery and report any associated clinical impact. BACKGROUND: Despite implementation of surgical safety initiatives, the intraoperative period is poorly documented with evidence of underreporting. Near miss analyses are undertaken in high-risk industries but not in surgical practice. METHODS: Case video and data from 2 laparoscopic total mesorectal excision randomized controlled trials were analyzed (ALaCaRT ACTRN12609000663257, 2D3D ISRCTN59485808). Intraoperative adverse events were identified and categorized using the observational clinical human reliability analysis technique. The EAES classification was applied by 2 blinded assessors. EAES grade 1 events (nonconsequential error, no damage, or need for correction) were considered near misses. Associated clinical impact was assessed with early morbidity and histopathology outcomes. RESULTS: One hundred seventy-five cases contained 1113 error events. Six hundred ninety-eight (62.7%) were near misses (median 3, IQR 2-5, range 0-15) with excellent inter-rater and test-retest reliability (κ=0.86, 95% CI 0.83-0.89, P < 0.001 and κ=0.88, 95% CI 0.85-0.9, P < 0.001 respectively). Significantly more near misses were seen in patients who developed early complications (4 (3-6) vs. 3 (2-4), P < 0.001). Higher numbers of near misses were seen in patients with more numerous (P = 0.002) and more serious early complications (P = 0.003). Cases containing major intraoperative adverse events contained significantly more near misses (5 (3-7) vs. 3 (2-5), P < 0.001) with a major event observed for every 19.4 near misses. CONCLUSION: Intraoperative adverse events and near misses can be reliably and objectively captured in advanced laparoscopic surgery. Near misses are commonplace and closely associated with morbidity outcomes.
Assuntos
Colectomia/métodos , Complicações Intraoperatórias/epidemiologia , Laparoscopia/métodos , Estadiamento de Neoplasias , Neoplasias Retais/cirurgia , Humanos , Complicações Intraoperatórias/diagnóstico , Segurança do Paciente , Neoplasias Retais/diagnóstico , Reprodutibilidade dos TestesRESUMO
Keloid scarring is a fibroproliferative disorder of the skin with unknown pathophysiology, characterised by fibrotic tissue that extends beyond the boundaries of the original wound. Therapeutic options are few and commonly ineffective, with keloids very commonly recurring even after surgery and adjunct treatments. Epigenetics, defined as alterations to the DNA not involving the base-pair sequence, is a key regulator of cell functions, and aberrant epigenetic modifications have been found to contribute to many pathologies. Multiple studies have examined many different epigenetic modifications in keloids, including DNA methylation, histone modification, microRNAs and long non-coding RNAs. These studies have established that epigenetic dysregulation exists in keloid scars, and successful future treatment of keloids may involve reverting these aberrant modifications back to those found in normal skin. Here we summarise the clinical and experimental studies available on the epigenetics of keloids, discuss the major open questions and future perspectives on the treatment of this disease.
Assuntos
Epigênese Genética , Queloide/genética , Reprogramação Celular/genética , Metilação de DNA/genética , Regulação da Expressão Gênica , Histonas/genética , HumanosRESUMO
BACKGROUND: Three-dimensional (3D) visual displays have been suggested to aid laparoscopic skills training by providing the depth cues not present in traditional two-dimensional (2D) displays. However, few studies have robustly investigated the impact of viewing mode (2D vs. 3D) on learning outcomes. PURPOSE: To examine how viewing mode (2D vs. 3D) impacts the acquisition and transferability of basic laparoscopic skills by comparing performance between transfer and control groups on a complete proficiency-based training program. METHOD: A counterbalanced between-subjects design was employed. Each participant was randomly allocated to one of four groups, comprising two transfer groups (trained in one viewing mode and tested in the alternate mode: the 2D â 3D and 3D â 2D groups) and two control groups (trained and tested in one viewing mode: the 2D â 2D and 3D â 3D groups). Participants completed proficiency-based training in six laparoscopic training tasks. Testing included two further repetitions of all tasks under test conditions. Objective performance measures included the total number of repetitions to reach proficiency, and total performance scores (i.e. time + error penalties across all repetitions) in training and testing. RESULTS: The groups trained in 3D demonstrated superior training performance (i.e. less time + errors) and took fewer repetitions to reach proficiency than the groups trained in 2D. The groups tested in 3D also demonstrated superior test performance compared to those tested in 2D. However, training mode did not yield significant test differences between the groups tested in 2D (i.e. 2D â 2D vs. 3D â 2D), or between the groups tested in 3D (i.e. 3D â 3D vs. 2D â 3D). CONCLUSION: Novices demonstrate superior performance in laparoscopic skills training using a 3D viewing mode compared to 2D. However, this does not necessarily translate to superior performance in subsequent testing or enhanced learning overall. Rather, test performance appears to be dictated by the viewing mode used during testing, not that of prior training.
Assuntos
Laparoscopia , Treinamento por Simulação , Competência Clínica , Humanos , Imageamento Tridimensional , Curva de AprendizadoRESUMO
The infectious life cycle of human papillomaviruses (HPVs) is tightly linked to keratinocyte differentiation. Evidence suggests a sophisticated interplay between host gene regulation and virus replication. Alternative splicing is an essential process for host and viral gene expression, and is generally upregulated by serine arginine-rich splicing factors (SRSFs). SRSF activity can be positively or negatively controlled by cycles of phosphorylation/dephosphorylation. Here we show that HPV16 infection leads to accumulation of the paradigm SRSF protein, SRSF1, in the cytoplasm in a keratinocyte differentiation-specific manner. Moreover, HPV16 infection leads to increased levels of cytoplasmic and nuclear phosphorylated SRSF1. SR protein kinase 1 (SRPK1) phosphorylates SRSF1. Similar to HPV upregulation of SRSF1, we demonstrate HPV upregulation of SRPK1 via the viral E2 protein. SRPK1 depletion or drug inhibition of SRPK1 kinase activity resulted in reduced levels of SRSF1, suggesting that phosphorylation stabilizes the protein in differentiated HPV-infected keratinocytes. Together, these data indicate HPV infection stimulates the SRPK1-SRSF axis in keratinocytes.
Assuntos
Processamento Alternativo/genética , Papillomavirus Humano 16/patogenicidade , Infecções por Papillomavirus/genética , Proteínas Serina-Treonina Quinases/genética , Células 3T3 , Animais , Células HeLa , Humanos , Queratinócitos/fisiologia , Camundongos , Fosforilação/genética , Fatores de Processamento de Serina-Arginina/genética , Regulação para Cima/genética , Proteínas Virais/genética , Replicação Viral/genéticaRESUMO
Small-animal physiology studies are typically complicated, but the level of complexity is greatly increased when performing live-animal X-ray imaging studies at synchrotron and compact light sources. This group has extensive experience in these types of studies at the SPring-8 and Australian synchrotrons, as well as the Munich Compact Light Source. These experimental settings produce unique challenges. Experiments are always performed in an isolated radiation enclosure not specifically designed for live-animal imaging. This requires equipment adapted to physiological monitoring and test-substance delivery, as well as shuttering to reduce the radiation dose. Experiment designs must also take into account the fixed location, size and orientation of the X-ray beam. This article describes the techniques developed to overcome the challenges involved in respiratory X-ray imaging of live animals at synchrotrons, now enabling increasingly sophisticated imaging protocols.
Assuntos
Radiografia/métodos , Mecânica Respiratória , Sistema Respiratório/diagnóstico por imagem , Síncrotrons , Aerossóis , Anestesia Geral/métodos , Animais , Autopsia/métodos , Tamanho Corporal , Temperatura Corporal , Umidificadores , Camundongos , Pentobarbital , Doses de Radiação , Ratos , Respiração Artificial/métodos , SuínosRESUMO
OBJECTIVE: Adjuvant protocols devised to enhance motor recovery in subacute stroke patients have failed to show benefits with respect to classic therapeutic interventions. Here, we evaluate the efficacy of a novel brain state-dependent intervention based on known mechanisms of memory and learning that is integrated as part of the weekly rehabilitation program in subacute stroke patients. METHODS: Twenty-four hospitalized subacute stroke patients were randomly assigned to 2 intervention groups: (1) the associative group received 30 pairings of a peripheral electrical nerve stimulus (ES) such that the generated afferent volley arrived precisely during the most active phase of the motor cortex as patients attempted to perform a movement; and (2) in the control group, the ES intensity was too low to generate a stimulation of the nerve. Functional (including the lower extremity Fugl-Meyer assessment [LE-FM; primary outcome measure]) and neurophysiological (changes in motor evoked potentials [MEPs]) assessments were performed prior to and following the intervention period. RESULTS: The associative group significantly improved functional recovery with respect to the control group (median [interquartile range] LE-FM improvement = 6.5 [3.5-8.25] and 3 [0.75-3], respectively; p = 0.029). Significant increases in MEP amplitude were seen following all sessions in the associative group only (p ≤ 0.006). INTERPRETATION: This is the first evidence of a clinical effect of a neuromodulatory intervention in the subacute phase of stroke. This was evident with relatively few repetitions in comparison to available techniques, making it a clinically viable approach. The results indicate the potential of the proposed neuromodulation system in daily clinical routine for stroke rehabilitation. ANN NEUROL 2019;85:84-95.
Assuntos
Encéfalo/fisiologia , Potencial Evocado Motor/fisiologia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Acidente Vascular Cerebral/fisiopatologiaRESUMO
Epigenetic regulatory mechanisms are essential for maintaining skin homeostasis and aid in the processes of wound healing. The nucleus co-ordinates gene expression using epigenetic regulatory mechanisms based on distinct chromatin structural states and their remodeling. These include DNA methylation and hydroxymethylation, post-translational histone modifications, ATP-dependent chromatin remodeling and higher-order chromatin structure and 3D genome organization. Epigenetic pathways play a key role in co-ordinating the behavior and activity of the multitude of cell types seen during skin repair, and research is now focusing on how wound healing can be modulated by altering the activity of certain reparative genes. Herein, we aim to highlight recent advances in understanding epigenetic regulatory mechanisms, with particular reference to those involved in keratinocyte and fibroblast biology. We also propose future directions for exploration of epigenetic mechanisms, and their potential clinical applications in acute wound care.
Assuntos
Cromatina/genética , Epigênese Genética , Histonas/genética , Queratinócitos/metabolismo , Pele/metabolismo , Cicatrização/genética , Animais , Cromatina/metabolismo , Metilação de DNA , Fibroblastos/metabolismo , Fibroblastos/patologia , Histonas/metabolismo , Humanos , Queratinócitos/patologia , Pele/patologiaRESUMO
Street connected young people (SCYP) are at risk of encountering negative life experiences, such as abuse, neglect, violence and exploitation. Nonetheless, some demonstrate remarkable resilience. This study therefore aimed to explore protective factors that promote resilience in SCYP in Guatemala City. Using ethnographic interviews and image elicitation eight young people and four adult educational outreach project coordinators participated within this study. Three key protective factors emerged that help develop resilience; Empowerment, as educational projects support SCYP and provide opportunities; Belongingness, encapsulated creating positive relationships, a sense of affinity and positive family environments; and Motivation which highlighted the importance of the young peoples' willpower, engagement with learning and help-seeking behaviour. Educational projects working with SCYP can help to develop resilience by empowering them for change, providing a sense of belonging, while also acknowledging their individual motivation for change.
Assuntos
Jovens em Situação de Rua/psicologia , Relações Interpessoais , Poder Psicológico , Psicologia do Adolescente , Resiliência Psicológica , Adolescente , Criança , Escolaridade , Relações Familiares , Feminino , Guatemala , Humanos , Masculino , Motivação , Fatores de Proteção , Mudança Social , Fatores SocioeconômicosRESUMO
OBJECTIVE: The aim of the study was to determine the efficacy of laparoscopic rectal resection (Lap) versus open laparotomy and rectal resection (Open) for rectal cancer on locoregional recurrence (LRR) and disease-free survival (DFS) at 2 years. SUMMARY BACKGROUND DATA: Although a Lap approach to colon cancer surgery may offer similar oncological outcomes to Open with potentially less morbidity, this remains to be clearly established for the treatment of rectal cancer. METHODS: A randomized, multicenter noninferiority phase 3 trial of 475 patients with T1 to T3 rectal adenocarcinoma <15âcm from anal verge, given Lap or Open and followed for a minimum 2 years to assess LRR, DFS, and overall survival (OS). RESULTS: Secondary endpoint analyses included 450 patients (95%) without metastases at baseline (mean age 64; 34% women) who received Lap (n = 225) or Open (n = 225). Median follow-up was 3.2 years (range: 0.1-5.4 yrs). LRR cumulative incidence at 2 years: Lap 5.4%; Open 3.1% [difference, 2.3%; 95% confidence interval (CI), -1.5% to 6.1%; hazard ratio (HR) 1.7; 95% CI, 0.74-3.9]. DFS at 2 years: Lap 80%; Open 82% (difference, 2.0%; 95% CI, -9.3% to 5.4%; HR for recurrence or death, 1.17; 95% CI, 0.81-1.68; P = 0.41). After adjustment for baseline factors HR = 1.07 (95% CI, 0.7-1.6). OS at 2 years: Lap 94%; Open 93% (difference 0.9%; 95% CI, -3.6% to 5.4%). CONCLUSIONS: Laparoscopic surgery for rectal cancer did not differ significantly from open surgery in effects on 2-year recurrence or DFS and OS. Confidence intervals included potentially clinically important differences favoring open resection, so that the combination of primary and secondary study endpoints may not support laparoscopic resection of rectal cancer as a routine standard of care and further follow-up is required.