Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 219
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 121(8): e2310561121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38354264

RESUMEN

Exposure to loud noise triggers sensory organ damage and degeneration that, in turn, leads to hearing loss. Despite the troublesome impact of noise-induced hearing loss (NIHL) in individuals and societies, treatment strategies that protect and restore hearing are few and insufficient. As such, identification and mechanistic understanding of the signaling pathways involved in NIHL are required. Biological zinc is mostly bound to proteins, where it plays major structural or catalytic roles; however, there is also a pool of unbound, mobile (labile) zinc. Labile zinc is mostly found in vesicles in secretory tissues, where it is released and plays a critical signaling role. In the brain, labile zinc fine-tunes neurotransmission and sensory processing. However, injury-induced dysregulation of labile zinc signaling contributes to neurodegeneration. Here, we tested whether zinc dysregulation occurs and contributes to NIHL in mice. We found that ZnT3, the vesicular zinc transporter responsible for loading zinc into vesicles, is expressed in cochlear hair cells and the spiral limbus, with labile zinc also present in the same areas. Soon after noise trauma, ZnT3 and zinc levels are significantly increased, and their subcellular localization is vastly altered. Disruption of zinc signaling, either via ZnT3 deletion or pharmacological zinc chelation, mitigated NIHL, as evidenced by enhanced auditory brainstem responses, distortion product otoacoustic emissions, and number of hair cell synapses. These data reveal that noise-induced zinc dysregulation is associated with cochlear dysfunction and recovery after NIHL, and point to zinc chelation as a potential treatment for mitigating NIHL.


Asunto(s)
Pérdida Auditiva Provocada por Ruido , Ratones , Animales , Pérdida Auditiva Provocada por Ruido/tratamiento farmacológico , Zinc , Cóclea , Ruido/efectos adversos , Audición , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Umbral Auditivo
2.
PLoS Biol ; 21(4): e3001964, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37011103

RESUMEN

Assembly of the hair bundle, the sensory organelle of the inner ear, depends on differential growth of actin-based stereocilia. Separate rows of stereocilia, labeled 1 through 3 from tallest to shortest, lengthen or shorten during discrete time intervals during development. We used lattice structured illumination microscopy and surface rendering to measure dimensions of stereocilia from mouse apical inner hair cells during early postnatal development; these measurements revealed a sharp transition at postnatal day 8 between stage III (row 1 and 2 widening; row 2 shortening) and stage IV (final row 1 lengthening and widening). Tip proteins that determine row 1 lengthening did not accumulate simultaneously during stages III and IV; while the actin-bundling protein EPS8 peaked at the end of stage III, GNAI3 peaked several days later-in early stage IV-and GPSM2 peaked near the end of stage IV. To establish the contributions of key macromolecular assemblies to bundle structure, we examined mouse mutants that eliminated tip links (Cdh23v2J or Pcdh15av3J), transduction channels (TmieKO), or the row 1 tip complex (Myo15ash2). Cdh23v2J/v2J and Pcdh15av3J/av3J bundles had adjacent stereocilia in the same row that were not matched in length, revealing that a major role of these cadherins is to synchronize lengths of side-by-side stereocilia. Use of the tip-link mutants also allowed us to distinguish the role of transduction from effects of transduction proteins themselves. While levels of GNAI3 and GPSM2, which stimulate stereocilia elongation, were greatly attenuated at the tips of TmieKO/KO row 1 stereocilia, they accumulated normally in Cdh23v2J/v2J and Pcdh15av3J/av3J stereocilia. These results reinforced the suggestion that the transduction proteins themselves facilitate localization of proteins in the row 1 complex. By contrast, EPS8 concentrates at tips of all TmieKO/KO, Cdh23v2J/v2J, and Pcdh15av3J/av3J stereocilia, correlating with the less polarized distribution of stereocilia lengths in these bundles. These latter results indicated that in wild-type hair cells, the transduction complex prevents accumulation of EPS8 at the tips of shorter stereocilia, causing them to shrink (rows 2 and 3) or disappear (row 4 and microvilli). Reduced rhodamine-actin labeling at row 2 stereocilia tips of tip-link and transduction mutants suggests that transduction's role is to destabilize actin filaments there. These results suggest that regulation of stereocilia length occurs through EPS8 and that CDH23 and PCDH15 regulate stereocilia lengthening beyond their role in gating mechanotransduction channels.


Asunto(s)
Mecanotransducción Celular , Estereocilios , Ratones , Animales , Estereocilios/metabolismo , Mecanotransducción Celular/fisiología , Actinas/metabolismo , Células Ciliadas Auditivas/metabolismo , Proteínas de Microfilamentos/metabolismo , Células Ciliadas Auditivas Internas/metabolismo , Cadherinas/genética , Cadherinas/metabolismo
3.
EMBO J ; 39(16): e103009, 2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32720716

RESUMEN

Exosomes are secreted extracellular vesicles carrying diverse molecular cargos, which can modulate recipient cell behaviour. They are thought to derive from intraluminal vesicles formed in late endosomal multivesicular bodies (MVBs). An alternate exosome formation mechanism, which is conserved from fly to human, is described here, with exosomes carrying unique cargos, including the GTPase Rab11, generated in Rab11-positive recycling endosomal MVBs. Release of Rab11-positive exosomes from cancer cells is increased relative to late endosomal exosomes by reducing growth regulatory Akt/mechanistic Target of Rapamycin Complex 1 (mTORC1) signalling or depleting the key metabolic substrate glutamine, which diverts membrane flux through recycling endosomes. Vesicles produced under these conditions promote tumour cell proliferation and turnover and modulate blood vessel networks in xenograft mouse models in vivo. Their growth-promoting activity, which is also observed in vitro, is Rab11a-dependent, involves ERK-MAPK-signalling and is inhibited by antibodies against amphiregulin, an EGFR ligand concentrated on these vesicles. Therefore, glutamine depletion or mTORC1 inhibition stimulates release from Rab11a compartments of exosomes with pro-tumorigenic functions, which we propose promote stress-induced tumour adaptation.


Asunto(s)
Proliferación Celular , Exosomas , Glutamina/deficiencia , Sistema de Señalización de MAP Quinasas , Neoplasias , Animales , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Exosomas/genética , Exosomas/metabolismo , Exosomas/patología , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo
4.
Insect Mol Biol ; 33(5): 467-480, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38335444

RESUMEN

The function of DNA methylation in insects and the DNA methyltransferase (Dnmt) genes that influence methylation remains uncertain. We used RNA interference to reduce the gene expression of Dnmt1 within the whitefly Bemisia tabaci (Hemiptera:Aleyrodidae; Gennadius), a hemipteran species that relies on Dnmt1 for proper gametogenesis. We then used RNA-seq to test an a priori hypothesis that meiosis-related genetic pathways would be perturbed. We generally did not find an overall effect on meiosis-related pathways. However, we found that genes in the Wnt pathway, genes associated with the entry into meiosis in vertebrates, were differentially expressed. Our results are consistent with Dnmt1 knockdown influencing specific pathways and not causing general transcriptional response. This is a finding that is also seen with other insect species. We also characterised the methylome of B. tabaci and assessed the influence of Dnmt1 knockdown on cytosine methylation. This species has methylome characteristics comparable to other hemipterans regarding overall level, enrichment within gene bodies, and a bimodal distribution of methylated/non-methylated genes. Very little differential methylation was observed, and difference in methylation were not associated with differences in gene expression. The effect on Wnt presents an interesting new candidate pathway for future studies.


Asunto(s)
Metilación de ADN , Hemípteros , Oocitos , Animales , Hemípteros/genética , Hemípteros/metabolismo , Oocitos/metabolismo , Femenino , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Interferencia de ARN , Vía de Señalización Wnt , Meiosis
5.
J Evol Biol ; 37(1): 100-109, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38285656

RESUMEN

The evolutionary repercussions of parental effects-the impact of the developmental environment provided by parents on offspring-are often discussed as static effects that can have negative influences on offspring fitness that may even persist across generations. However, individuals are not passive recipients and may mitigate the persistence of parental effects through their behaviour. Here, we tested how the burying beetle, Nicrophorus orbicollis, a species with complex parental care, responded to poor parenting. We cross-fostered young and manipulated the duration of parental care received and measured the impact on traits of both F1 and F2 offspring to experimentally extricate the effect of poor parenting from other parental effects. As expected, reducing parental care negatively affected traits that are ecologically important for burying beetles, including F1 offspring development time and body size. However, F1 parents that received reduced care as larvae spent more time feeding F2 offspring than parents that received full care as larvae. As a result, both the number and mass of F2 offspring were unaffected by the developmental experience of their parents. Our results show that flexible parental care may be able to overcome poor developmental environments and limit negative parental effects to a single generation.


Asunto(s)
Escarabajos , Responsabilidad Parental , Animales , Larva , Escarabajos/genética , Conducta Animal , Evolución Biológica
6.
J Phys Chem A ; 128(30): 6116-6123, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39008894

RESUMEN

We demonstrate the use of gradient-boosted ensemble models that accurately predict emission wavelengths in benzobis[1,2-d:4,5-d']oxazole (BBO) based fluorescent emitters. We have curated a database of 50 molecules from previously published data by the Jeffries-EL group using density functional theory (DFT) computed ground and excited state features. We consider two machine learning (ML) models based on (i) whole cruciform molecules and (ii) their constituent fragment molecules. Both ML models provide accurate predictions with root-mean-square errors between 30 and 36 nm, competitive with state-of-the-art deep learning models trained on orders of magnitude more molecules, and this accuracy holds even when tested on four new BBO emitters unseen by the models. We also provide an interpretable feature importance analysis and discuss the relevant relationships between DFT and changes in predicted emission wavelength.

7.
J Am Chem Soc ; 145(25): 13581-13591, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37314891

RESUMEN

The resorcinol-terpene phytocannabinoid template is a privileged scaffold for the development of diverse therapeutics targeting the endocannabinoid system. Axially chiral cannabinols (axCBNs) are unnatural cannabinols (CBNs) that bear an additional C10 substituent, which twists the cannabinol biaryl framework out of planarity creating an axis of chirality. This unique structural modification is hypothesized to enhance both the physical and biological properties of cannabinoid ligands, thus ushering in the next generation of endocannabinoid system chemical probes and cannabinoid-inspired leads for drug development. In this full report, we describe the philosophy guiding the design of axCBNs as well as several synthetic strategies for their construction. We also introduce a second class of axially chiral cannabinoids inspired by cannabidiol (CBD), termed axially chiral cannabidiols (axCBDs). Finally, we provide an analysis of axially chiral cannabinoid (axCannabinoid) atropisomerism, which spans two classes (class 1 and 3 atropisomers), and provide first evidence that axCannabinoids retain─and in some cases, strengthen─affinity and functional activity at cannabinoid receptors. Together, these findings present a promising new direction for the design of novel cannabinoid ligands for drug discovery and exploration of the complex endocannabinoid system.


Asunto(s)
Cannabidiol , Cannabinoides , Endocannabinoides , Receptores de Cannabinoides , Ligandos , Cannabinol
8.
Biochem Soc Trans ; 51(2): 675-689, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-36929376

RESUMEN

Plasticity in developmental processes gives rise to remarkable environmentally induced phenotypes. Some of the most striking and well-studied examples of developmental plasticity are seen in insects. For example, beetle horn size responds to nutritional state, butterfly eyespots are enlarged in response to temperature and humidity, and environmental cues also give rise to the queen and worker castes of eusocial insects. These phenotypes arise from essentially identical genomes in response to an environmental cue during development. Developmental plasticity is taxonomically widespread, affects individual fitness, and may act as a rapid-response mechanism allowing individuals to adapt to changing environments. Despite the importance and prevalence of developmental plasticity, there remains scant mechanistic understanding of how it works or evolves. In this review, we use key examples to discuss what is known about developmental plasticity in insects and identify fundamental gaps in the current knowledge. We highlight the importance of working towards a fully integrated understanding of developmental plasticity in a diverse range of species. Furthermore, we advocate for the use of comparative studies in an evo-devo framework to address how developmental plasticity works and how it evolves.


Asunto(s)
Adaptación Fisiológica , Insectos , Animales , Insectos/genética , Fenotipo , Adaptación Fisiológica/genética , Evolución Biológica
9.
Pharmacol Res ; 197: 106966, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37865129

RESUMEN

Though efficacious in managing chronic, severe pain, opioid analgesics are accompanied by significant adverse effects including constipation, tolerance, dependence, and respiratory depression. The life-threatening risks associated with µ opioid receptor agonist-based analgesics challenges their use in clinic. A rational approach to combatting these adverse effects is to develop agents that incorporate activity at a second pharmacologic target in addition to µ opioid receptor activation. The promise of such bivalent or bifunctional ligands is the development of an analgesic with an improved side effect profile. In this review, we highlight ongoing efforts in the development of bivalent and bifunctional analgesics that combine µ agonism with efficacy at κ and δ opioid receptors, the nociceptin opioid peptide (NOP) receptor, σ receptors, and cannabinoid receptors. Several examples of bifunctional analgesics in preclinical and clinical development are highlighted, as are strategies being employed toward the rational design of novel agents.


Asunto(s)
Dolor Crónico , Receptores Opioides , Humanos , Analgésicos/efectos adversos , Analgésicos Opioides/efectos adversos , Manejo del Dolor , Receptor de Nociceptina , Ligandos
10.
Radiographics ; 43(7): e220209, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37319026

RESUMEN

Small solid renal masses (SRMs) are frequently detected at imaging. Nearly 20% are benign, making careful evaluation with MRI an important consideration before deciding on management. Clear cell renal cell carcinoma (ccRCC) is the most common renal cell carcinoma subtype with potentially aggressive behavior. Thus, confident identification of ccRCC imaging features is a critical task for the radiologist. Imaging features distinguishing ccRCC from other benign and malignant renal masses are based on major features (T2 signal intensity, corticomedullary phase enhancement, and the presence of microscopic fat) and ancillary features (segmental enhancement inversion, arterial-to-delayed enhancement ratio, and diffusion restriction). The clear cell likelihood score (ccLS) system was recently devised to provide a standardized framework for categorizing SRMs, offering a Likert score of the likelihood of ccRCC ranging from 1 (very unlikely) to 5 (very likely). Alternative diagnoses based on imaging appearance are also suggested by the algorithm. Furthermore, the ccLS system aims to stratify which patients may or may not benefit from biopsy. The authors use case examples to guide the reader through the evaluation of major and ancillary MRI features of the ccLS algorithm for assigning a likelihood score to an SRM. The authors also discuss patient selection, imaging parameters, pitfalls, and areas for future development. The goal is for radiologists to be better equipped to guide management and improve shared decision making between the patient and treating physician. © RSNA, 2023 Quiz questions for this article are available in the supplemental material. See the invited commentary by Pedrosa in this issue.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/diagnóstico , Neoplasias Renales/patología , Imagen por Resonancia Magnética/métodos , Diagnóstico Diferencial , Estudios Retrospectivos
11.
Am J Epidemiol ; 191(6): 1125-1139, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35136928

RESUMEN

Few biomarker-based validation studies have examined error in online self-report dietary assessment instruments, and food records (FRs) have been considered less than food frequency questionnaires (FFQs) and 24-hour recalls (24HRs). We investigated measurement error in online and paper-based FFQs, online 24HRs, and paper-based FRs in 3 samples drawn primarily from 3 cohorts, comprising 1,393 women and 1,455 men aged 45-86 years. Data collection occurred from January 2011 to October 2013. Attenuation factors and correlation coefficients between reported and true usual intake for energy, protein, sodium, potassium, and respective densities were estimated using recovery biomarkers. Across studies, average attenuation factors for energy were 0.07, 0.07, and 0.19 for a single FFQ, 24HR, and FR, respectively. Correlation coefficients for energy were 0.24, 0.23, and 0.40, respectively. Excluding energy, the average attenuation factors across nutrients and studies were 0.22 for a single FFQ, 0.22 for a single 24HR, and 0.51 for a single FR. Corresponding correlation coefficients were 0.31, 0.34, and 0.53, respectively. For densities (nutrient expressed relative to energy), the average attenuation factors across studies were 0.37, 0.17, and 0.50, respectively. The findings support prior research suggesting different instruments have unique strengths that should be leveraged in epidemiologic research.


Asunto(s)
Dieta , Evaluación Nutricional , Biomarcadores , Estudios de Cohortes , Encuestas sobre Dietas , Ingestión de Energía , Femenino , Humanos , Masculino , Recuerdo Mental , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
12.
Mol Ecol ; 31(20): 5326-5338, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35951025

RESUMEN

Flexible interactions between parents and offspring are essential for buffering families against variable, unpredictable, and challenging environmental conditions. In the subsocial carrion beetle, Nicrophorus orbicollis, mid-summer temperatures impose steep fitness costs on parents and offspring but do not elicit behavioural plasticity in parents. Here, we ask if plasticity of gene expression underpins this behavioural stability or facilitates independent compensation by larvae. To test this, we characterized gene expression of parents and offspring before and during active parenting under benign (20°C) and stressful (24°C) temperatures to identify genes of parents and offspring associated with thermal response, parenting/being parented, and gene expression plasticity associated with behavioural stability of parental care. The main effects of thermal and social condition each shaped patterns of gene expression in females, males, and larvae. In addition, we implicated 79 genes in females as "buffering" parental behaviour across environments. The majority of these underwent significant changes in expression in actively parenting mothers at the benign temperature, but not at the stressful temperature. Our results suggest that neither genetic programmes for parenting nor their effects on offspring gene expression are fundamentally different under stressful conditions, and that behavioural stability is associated primarily with the maintenance of existing genetic programmes rather than replacement or supplementation. Thus, while selection for compensatory gene expression could expand the range of thermal conditions parents will tolerate, without expanding the toolkit of genes involved selection is unlikely to lead to adaptive changes of function.


Asunto(s)
Escarabajos , Responsabilidad Parental , Animales , Escarabajos/genética , Femenino , Expresión Génica , Masculino , Temperatura
13.
Int J Colorectal Dis ; 37(10): 2125-2136, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36044045

RESUMEN

PURPOSE: This study aimed to establish the functional impact of displacement of urogenital organs after abdominoperineal resection (APR) using validated questionnaires. METHODS: Patients who underwent APR for primary or recurrent rectal cancer (2001-2018) with evaluable pre- and postoperative radiological imaging and completed urinary (UDI-6, IIQ-7) and sexual questionnaires (male, IIEF; female, FSFI, FSDS-R) were included from 16 centers. Absolute displacement of the internal urethral orifice, posterior bladder wall, distal end of the prostatic urethra, and cervix were correlated to urogenital function by calculating Spearman's Rho (ρ). Median function scores were compared between minimal or substantial displacement using median split. RESULTS: There were 89 male and 36 female patients included, of whom 45 and 19 were sexually active after surgery. Absolute displacement of the internal urethral orifice and posterior bladder wall was not correlated with UDI-6 in men (ρ = 0.119 and ρ = 0.022) nor in women (ρ = - 0.098 and ρ = - 0.154). In men with minimal and substantial displacement of the internal urethral orifice, median UDI-6 scores were 10 (IQR 0-22) and 17 (IQR 5-21), respectively, with corresponding scores of 25 (IQR 10-46) and 21 (IQR 16-36) in women. Displacement of the cervix and FSDS-R were correlated (ρ = 0.433) in sexually active patients. CONCLUSION: This first analysis on functional impact of urogenital organ displacement after APR suggests that more displacement of the cervix might be associated with worse sexual function, while the data does not indicate any potential functional impact of bladder displacement. Studies are needed to further explore this underexposed topic.


Asunto(s)
Proctectomía , Calidad de Vida , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia , Conducta Sexual , Encuestas y Cuestionarios
14.
Surg Endosc ; 36(1): 489-497, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33544250

RESUMEN

BACKGROUND: Treatment of early rectal cancer is evolving towards organ-preserving therapy which includes endoscopic resection and transanal approaches. We aimed to explore the role of local treatments such as endoscopic polypectomy (Endoscopic Mucosal Resection (EMR) or Endoscopic submucosal dissection (ESD)) and transanal endoscopic microsurgery/ transanal minimal invasive surgery (TEM/TAMIS) in patients who had early rectal cancer. We considered these outcomes alongside conventional major surgery using total mesorectal excision (TME) for early stage disease. METHODS: All patients identified at MDT with early stage rectal cancer at our institution between 2010 and 2019 were included. Long-term outcomes in terms of local recurrence, survival and procedure-specific morbidity were analysed. RESULTS: In total, 536 patients with rectal cancer were identified, of which 112 were included based on their pre-operative identification at the MDT on the basis that they had node-negative early rectal cancer. Among these, 30 patients (27%) had the lesion excised by flexible endoscopic polypectomy techniques (EMR/ESD), 67 (60%) underwent TEM/TAMIS and 15 (13%) had major surgery. There were no differences in patient demographics between the three groups except for TEM/TAMIS patients being more likely to be referred from another hospital (p < 0.001) and they were less active (WHO performance status p = 0.04). There were no significant differences in overall survival rates and cancer-specific survival between the three treatment groups. The 5-year overall survival rate for endoscopic polypectomy, TEM/TAMIS or major resection was 96% versus 90% and 88%, respectively (p = 0.89). The 5- year cancer-specific survival rate was 96%, versus 96% and 100%, respectively (p = 0.74). CONCLUSION: Endoscopic polypectomy by EMR/ESD is an appropriate local treatment for early stage rectal cancer in selected patients. It is possible to achieve good oncological outcomes with a polypectomy similar to TEM/TAMIS and major surgery; however, a multidisciplinary approach is necessary enabling close surveillance and the use of adjuvant radiotherapy.


Asunto(s)
Resección Endoscópica de la Mucosa , Neoplasias del Recto , Microcirugía Endoscópica Transanal , Resección Endoscópica de la Mucosa/métodos , Humanos , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/etiología , Radioterapia Adyuvante , Neoplasias del Recto/patología , Recto/patología , Microcirugía Endoscópica Transanal/métodos , Resultado del Tratamiento
15.
Adv Physiol Educ ; 46(2): 246-250, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35113680

RESUMEN

There is evidence that demonstrates that teaching preclinical and clinical material can have numerous benefits for both students and teachers, with the majority of literature focusing on peer medical student teaching. There is a dearth of literature exploring the benefit of medical students teaching undergraduate, pre-health professional students and using clinical cases in this setting. We explore our implementation of a team-based learning curriculum built around clinical cases to teach advanced physiology and introduce pathology, pharmacology, and interprofessional collaboration for pre-health students. This course was entirely taught by medical students. Course evaluations and future implications are discussed.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Curriculum , Personal de Salud , Humanos
16.
Circulation ; 142(21): 2016-2028, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33100036

RESUMEN

BACKGROUND: Left ventricular assist device (LVAD) unloading and hemodynamic support in patients with advanced chronic heart failure can result in significant improvement in cardiac function allowing LVAD removal; however, the rate of this is generally considered to be low. This prospective multicenter nonrandomized study (RESTAGE-HF [Remission from Stage D Heart Failure]) investigated whether a protocol of optimized LVAD mechanical unloading, combined with standardized specific pharmacological therapy to induce reverse remodeling and regular testing of underlying myocardial function, could produce a higher incidence of LVAD explantation. METHODS: Forty patients with chronic advanced heart failure from nonischemic cardiomyopathy receiving the Heartmate II LVAD were enrolled from 6 centers. LVAD speed was optimized with an aggressive pharmacological regimen, and regular echocardiograms were performed at reduced LVAD speed (6000 rpm, no net flow) to test underlying myocardial function. The primary end point was the proportion of patients with sufficient improvement of myocardial function to reach criteria for explantation within 18 months with sustained remission from heart failure (freedom from transplant/ventricular assist device/death) at 12 months. RESULTS: Before LVAD, age was 35.1±10.8 years, 67.5% were men, heart failure mean duration was 20.8±20.6 months, 95% required inotropic and 20% temporary mechanical support, left ventricular ejection fraction was 14.5±5.3%, end-diastolic diameter was 7.33±0.89 cm, end-systolic diameter was 6.74±0.88 cm, pulmonary artery saturations were 46.7±9.2%, and pulmonary capillary wedge pressure was 26.2±7.6 mm Hg. Four enrolled patients did not undergo the protocol because of medical complications unrelated to the study procedures. Overall, 40% of all enrolled (16/40) patients achieved the primary end point, P<0.0001, with 50% (18/36) of patients receiving the protocol being explanted within 18 months (pre-explant left ventricular ejection fraction, 57±8%; end-diastolic diameter, 4.81±0.58 cm; end-systolic diameter, 3.53±0.51 cm; pulmonary capillary wedge pressure, 8.1±3.1 mm Hg; pulmonary artery saturations 63.6±6.8% at 6000 rpm). Overall, 19 patients were explanted (19/36, 52.3% of those receiving the protocol). The 15 ongoing explanted patients are now 2.26±0.97 years after explant. After explantation survival free from LVAD or transplantation was 90% at 1-year and 77% at 2 and 3 years. CONCLUSIONS: In this multicenter prospective study, this strategy of LVAD support combined with a standardized pharmacological and cardiac function monitoring protocol resulted in a high rate of LVAD explantation and was feasible and reproducible with explants occurring in all 6 participating sites. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01774656.


Asunto(s)
Remoción de Dispositivos , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Recuperación de la Función/fisiología , Función Ventricular Izquierda/fisiología , Adulto , Remoción de Dispositivos/tendencias , Femenino , Insuficiencia Cardíaca/fisiopatología , Corazón Auxiliar/tendencias , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Inducción de Remisión/métodos
17.
Int J Gynecol Pathol ; 40(4): 349-354, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32925442

RESUMEN

A 37-yr-old woman presented to the gynecology clinic with abnormal uterine bleeding in the setting of known, large uterine fibroids. Preoperative endometrial biopsy identified atypical melanocytic cells concerning for uterine melanoma. Care was transferred to the gynecologic oncology service for hysterectomy. Intraoperative findings included macular, blue-black pigmentation of the peritoneum of the bladder and cervix, which was resected and sent for frozen section, confirming melanocytic neoplasia. The hysterectomy revealed multiple tan leiomyomas up to 12 cm, and a distinct 3 cm black, incompletely circumscribed mass in the endomyometrium composed of bland spindled cells with delicate melanin granules. The tumor cells were positive for Sox-10, BAP1, and Mart-1 (Melan-A) and negative for PRAME, PD-L1, and BRAFV600E by immunostains. Microscopic elements of similar melanocytes and melanophages were found in the cervix and bladder peritoneum. Molecular analysis of the uterine tumor identified a GNA11 mutation but no TERT or BAP1 mutation. The uterine melanocytic tumor has characteristic findings of a cellular blue nevus arising in association with dendritic melanocytosis of Mullerian and pelvic tissues, a rarely seen benign phenomenon that should be distinguished from malignant melanoma of the upper genital tract.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP/genética , Leiomioma/diagnóstico por imagen , Melanoma/diagnóstico por imagen , Nevo Azul/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Uterinas/diagnóstico por imagen , Adulto , Cuello del Útero/patología , Diagnóstico Diferencial , Endometrio/diagnóstico por imagen , Endometrio/patología , Femenino , Humanos , Histerectomía , Leiomioma/patología , Leiomioma/cirugía , Melanocitos/patología , Melanoma/patología , Mutación , Nevo Azul/patología , Nevo Azul/cirugía , Pelvis/diagnóstico por imagen , Pelvis/patología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Resultado del Tratamiento , Vejiga Urinaria/patología , Neoplasias Uterinas/patología
18.
Org Biomol Chem ; 19(18): 4107-4117, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33978029

RESUMEN

In this study, a new environmentally benign iodine-mediated one-pot iodocyclization/alkylation strategy for the synthesis of benzo[b]thiophene derivatives starting from 2-alkynylthioanisoles was developed. The synthesis of a diverse population of 2,3-disubstituted benzo[b]thiophenes was achieved in high yields by employing moderate reaction conditions using 1,3-dicarbonyl substrates as the nucleophile and various substituted propargyl alcohols as both the cyclization precursor and the alkylating agent. This method resulted in the formation of a series of complex structures obtained in a single step. Additionally, a strategy was devised for the one pot iodocyclization/oxidation of propargyl alcohols into carbonyl functionalized benzo[b]thiophene structures. These green one-pot reaction processes were designed to reduce wastes and byproducts while generating a complex substitution pattern on the benzo[b]thiophene structure. The reported methodologies may be used to synthesize more functionalized benzo[b]thiophene structures that can be used in both biomedical and organic electronic applications.


Asunto(s)
Tiofenos
19.
J Cutan Pathol ; 48(2): 285-289, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32519331

RESUMEN

Dermatofibrosarcoma protuberans (DFSP) is a rare sarcoma of the skin arising from the dermis. Its location is most commonly presented on the trunk of middle-aged adults and rarely on the face. The characteristic genetic aberration in the form of a reciprocal translocation t(17;22)(q21;q13) or a ring fusing the COL1A1 and PDGFB genes is found in 90% of DFSP. We present a case of a 42-year-old man who presented with a DFSP on the left cheek with foci of myxoid-fibrosarcomatous transformation. A conventional chromosomal analysis revealed a complex karyotype without a supernumerary ring chromosome or a linear translocation t(17;22). Comparative genome hybridization and fluorescence in-situ hybridization revealed the fusion of COL1A1 and PDGFB probes inserted in chromosome 15. This is a unique case of DFSP characterized by a rare body location, unique histopathological features, and novel chromosome COL1A1-PDGFB insertion, and may help guide future diagnostic and patient care modalities.


Asunto(s)
Cromosomas Humanos Par 15 , Neoplasias Faciales , Fibrosarcoma , Mutagénesis Insercional , Proteínas de Fusión Oncogénica , Neoplasias Cutáneas , Adulto , Cromosomas Humanos Par 15/genética , Cromosomas Humanos Par 15/metabolismo , Cromosomas Humanos Par 17/genética , Cromosomas Humanos Par 17/metabolismo , Cromosomas Humanos Par 22/genética , Cromosomas Humanos Par 22/metabolismo , Neoplasias Faciales/genética , Neoplasias Faciales/metabolismo , Neoplasias Faciales/patología , Fibrosarcoma/genética , Fibrosarcoma/metabolismo , Fibrosarcoma/patología , Humanos , Masculino , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Translocación Genética
20.
Colorectal Dis ; 23(11): 2923-2931, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34427972

RESUMEN

AIM: This study aimed to quantify displacement of urogenital organs after abdominoperineal resection (APR), and to explore patient and treatment characteristics associated with displacement. METHOD: Patients from 16 centres who underwent APR for primary or recurrent rectal cancer (2001-2018) with evaluable preoperative and 6-18 months postoperative radiological imaging were included in the study. Anatomical landmarks on sagittal images were related to a coordinate system based on reference lines between fixed bony structures and absolute displacements were calculated using the Pythagorean theorem. Rotation of landmarks was measured relative to a pubic-S5 reference line. RESULTS: There were 248 patients included of which 171 were men and 77 women. The median displacement of the internal urethral orifice was 25 mm in men (maximum 65), and 17 mm in women (maximum 50). Rotation of the internal urethral orifice was in a caudal direction in 160/170 (94%) of men and 65/73 (89%) of women, with a median of 32 degrees (maximum 85) and 33 degrees (maximum 83), respectively. Displacements of the posterior bladder wall, distal end of prostatic urethra and cervix were significantly correlated with the internal urethral orifice. In linear regression analysis, biological mesh reconstruction of the pelvic floor and visceral interposition were significantly associated with increased displacement of the internal urethral orifice, and female gender and any filling of the presacral space with decreased displacement. CONCLUSIONS: Substantial absolute displacement and rotation of urogenital organs after APR for rectal cancer were observed, but with high variability among both men and women, and being significantly associated with reconstructive interventions.


Asunto(s)
Proctectomía , Neoplasias del Recto , Femenino , Humanos , Masculino , Recurrencia Local de Neoplasia , Diafragma Pélvico , Perineo/cirugía , Proctectomía/efectos adversos , Neoplasias del Recto/cirugía , Uretra
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA