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Relativistic jets are observed from accreting and cataclysmic transients throughout the Universe, and have a profound impact on their surroundings1,2. Despite their importance, their launch mechanism is not known. For accreting neutron stars, the speed of their compact jets can reveal whether the jets are powered by magnetic fields anchored in the accretion flow3 or in the star itself4,5, but so far no such measurements exist. These objects can show bright explosions on their surface due to unstable thermonuclear burning of recently accreted material, called type-I X-ray bursts6, during which the mass-accretion rate increases7-9. Here, we report on bright flares in the jet emission for a few minutes after each X-ray burst, attributed to the increased accretion rate. With these flares, we measure the speed of a neutron star compact jet to be v = 0.38 - 0.08 + 0.11 c , much slower than those from black holes at similar luminosities. This discovery provides a powerful new tool in which we can determine the role that individual system properties have on the jet speed, revealing the dominant jet launching mechanism.
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Powerful relativistic jets are one of the main ways in which accreting black holes provide kinetic feedback to their surroundings. Jets launched from or redirected by the accretion flow that powers them are expected to be affected by the dynamics of the flow, which for accreting stellar-mass black holes has shown evidence for precession1 due to frame-dragging effects that occur when the black-hole spin axis is misaligned with the orbital plane of its companion star2. Recently, theoretical simulations have suggested that the jets can exert an additional torque on the accretion flow3, although the interplay between the dynamics of the accretion flow and the launching of the jets is not yet understood. Here we report a rapidly changing jet orientation-on a time scale of minutes to hours-in the black-hole X-ray binary V404 Cygni, detected with very-long-baseline interferometry during the peak of its 2015 outburst. We show that this changing jet orientation can be modelled as the Lense-Thirring precession of a vertically extended slim disk that arises from the super-Eddington accretion rate4. Our findings suggest that the dynamics of the precessing inner accretion disk could play a role in either directly launching or redirecting the jets within the inner few hundred gravitational radii. Similar dynamics should be expected in any strongly accreting black hole whose spin is misaligned with the inflowing gas, both affecting the observational characteristics of the jets and distributing the black-hole feedback more uniformly over the surrounding environment5,6.
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Oscillatory signals propagate in the basal ganglia from prototypic neurons in the external globus pallidus (GPe) to their target neurons in the substantia nigra pars reticulata (SNr), internal pallidal segment, and subthalamic nucleus. Neurons in the GPe fire spontaneously, so oscillatory input signals can be encoded as changes in timing of action potentials within an ongoing spike train. When GPe neurons were driven by an oscillatory current in male and female mice, these spike-timing changes produced spike-oscillation coherence over a range of frequencies extending at least to 100 Hz. Using the known kinetics of the GPeâSNr synapse, we calculated the postsynaptic currents that would be generated in SNr neurons from the recorded GPe spike trains. The ongoing synaptic barrage from spontaneous firing, frequency-dependent short-term depression, and stochastic fluctuations at the synapse embed the input oscillation into a noisy sequence of synaptic currents in the SNr. The oscillatory component of the resulting synaptic current must compete with the noisy spontaneous synaptic barrage for control of postsynaptic SNr neurons, which have their own frequency-dependent sensitivities. Despite this, SNr neurons subjected to synaptic conductance changes generated from recorded GPe neuron firing patterns also became coherent with oscillations over a broad range of frequencies. The presynaptic, synaptic, and postsynaptic frequency sensitivities were all dependent on the firing rates of presynaptic and postsynaptic neurons. Firing rate changes, often assumed to be the propagating signal in these circuits, do not encode most oscillation frequencies, but instead determine which signal frequencies propagate effectively and which are suppressed.SIGNIFICANCE STATEMENT Oscillations are present in all the basal ganglia nuclei, include a range of frequencies, and change over the course of learning and behavior. Exaggerated oscillations are a hallmark of basal ganglia pathologies, and each has a specific frequency range. Because of its position as a hub in the basal ganglia circuitry, the globus pallidus is a candidate origin for oscillations propagating between nuclei. We imposed low-amplitude oscillations on individual globus pallidus neurons at specific frequencies and measured the coherence between the oscillation and firing as a function of frequency. We then used these responses to measure the effectiveness of oscillatory propagation to other basal ganglia nuclei. Propagation was effective for oscillation frequencies as high as 100 Hz.
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Porción Reticular de la Sustancia Negra , Núcleo Subtalámico , Masculino , Femenino , Ratones , Animales , Ganglios Basales/fisiología , Globo Pálido , Potenciales Sinápticos , Potenciales de Acción/fisiologíaRESUMEN
Autonomously firing GABAergic neurons in the external globus pallidus (GPe) form a local synaptic network. In slices, most GPe neurons receive a continuous inhibitory synaptic barrage from 1 or 2 presynaptic GPe neurons. We measured the barrage's effect on the firing rate and regularity of GPe neurons in male and female mice using perforated patch recordings. Silencing the firing of parvalbumin-positive (PV+) GPe neurons by activating genetically expressed Archaerhodopsin current increased the firing rate and regularity of PV- neurons. In contrast, silencing Npas1+ GPe neurons with Archaerhodopsin had insignificant effects on Npas1- neuron firing. Blocking spontaneous GABAergic synaptic input with gabazine reproduced the effects of silencing PV+ neuron firing on the firing rate and regularity of Npas1+ neurons and had similar effects on PV+ neuron firing. To simulate the barrage, we constructed conductance waveforms for dynamic clamp based on experimentally measured inhibitory postsynaptic conductance trains from 1 or 2 unitary local connections. The resulting inhibition replicated the effect on firing seen in the intact active network in the slice. We then increased the number of unitary inputs to match estimates of local network connectivity in vivo As few as 5 unitary inputs produced large increases in firing irregularity. The firing rate was also reduced initially, but PV+ neurons exhibited a slow spike-frequency adaptation that partially restored the rate despite sustained inhibition. We conclude that the irregular firing pattern of GPe neurons in vivo is largely due to the ongoing local inhibitory synaptic barrage produced by the spontaneous firing of other GPe neurons.SIGNIFICANCE STATEMENT Functional roles of local axon collaterals in the external globus pallidus (GPe) have remained elusive because of difficulty in isolating local inhibition from other GABAergic inputs in vivo, and in preserving the autonomous firing of GPe neurons and detecting their spontaneous local inputs in slices. We used perforated patch recordings to detect spontaneous local inputs during rhythmic firing. We found that the autonomous firing of single presynaptic GPe neurons produces inhibitory synaptic barrages that significantly alter the firing regularity of other GPe neurons. Our findings suggest that, although GPe neurons receive input from only a few other GPe neurons, each local connection has a large impact on their firing.
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Neuronas GABAérgicas , Globo Pálido , Ratones , Masculino , Femenino , Animales , Globo Pálido/fisiología , Axones , Parvalbúminas , Proteínas del Tejido Nervioso , Factores de Transcripción con Motivo Hélice-Asa-Hélice BásicoRESUMEN
Two subtypes of striatal spiny projection neurons, iSPNs and dSPNs, whose axons form the "indirect" and "direct" pathways of the basal ganglia, respectively, both make synaptic connections in the external globus pallidus (GPe) but are usually found to have different effects on behavior. Activation of the terminal fields of iSPNs or dSPNs generated compound currents in almost all GPe neurons. To determine whether iSPNs and dSPNs have the same or different effects on pallidal neurons, we studied the unitary synaptic currents generated in GPe neurons by action potentials in single striatal neurons. We used optogenetic excitation to elicit repetitive firing in a small number of nearby SPNs, producing sparse barrages of inhibitory postsynaptic currents (IPSCs) in GPe neurons. From these barrages, we isolated sequences of IPSCs with similar time courses and amplitudes, which presumably arose from the same SPN. There was no difference between the amplitudes of unitary IPSCs generated by the indirect and direct pathways. Most unitary IPSCs were small, but a subset from each pathway were much larger. To determine the effects of these unitary synaptic currents on the action potential firing of GPe neurons, we drove SPNs to fire as before and recorded the membrane potential of GPe neurons. Large unitary potentials from iSPNs and dSPNs perturbed the spike timing of GPe neurons in a similar way. Most SPN-GPe neuron pairs are weakly connected, but a subset of pairs in both pathways are strongly connected.NEW & NOTEWORTHY This is the first study to record the synaptic currents generated by single identified direct or indirect pathway striatal neurons on single pallidal neurons. Each GPe neuron receives synaptic inputs from both pathways. Most striatal neurons generate small synaptic currents that become influential when occurring together, but a few are powerful enough to be individually influential.
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Potenciales Postsinápticos Inhibidores , Neuronas , Optogenética , Animales , Ratones , Neuronas/fisiología , Potenciales Postsinápticos Inhibidores/fisiología , Cuerpo Estriado/fisiología , Cuerpo Estriado/citología , Globo Pálido/fisiología , Globo Pálido/citología , Potenciales de Acción/fisiología , Masculino , Ratones Endogámicos C57BL , Femenino , Vías Nerviosas/fisiología , Sinapsis/fisiologíaRESUMEN
BACKGROUND: Patients with severe-to-profound hearing loss may benefit from management with cochlear implants. These patients need a referral to a cochlear implant team for further assessment and possible surgery. The referral pathway may result in varied access to hearing healthcare. This study aimed to explore referral patterns and whether there were any socioeconomic or ethnic associations with the likelihood of referral. The primary outcome was to determine factors influencing referral for implant assessment. The secondary outcome was to identify factors impacting whether healthcare professionals had discussed the option of referral. METHODS AND FINDINGS: A multicentre multidisciplinary observational study was conducted in secondary care Otolaryngology and Audiology units in Great Britain. Adults fulfilling NICE (2019) audiometric criteria for implant assessment were identified over a 6-month period between 1 July and 31 December 2021. Patient- and site-specific characteristics were extracted. Multivariable binary logistic regression was employed to compare a range of factors influencing the likelihood of implant discussion and referral including patient-specific (demographics, past medical history, and degree of hearing loss) and site-specific factors (cochlear implant champion and whether the hospital performed implants). Hospitals across all 4 devolved nations of the UK were invited to participate, with data submitted from 36 urban hospitals across England, Scotland, and Wales. Nine hospitals (25%) conducted cochlear implant assessments. The majority of patients lived in England (n = 5,587, 86.2%); the rest lived in Wales (n = 419, 6.5%) and Scotland (n = 233, 3.6%). The mean patient age was 72 ± 19 years (mean ± standard deviation); 54% were male, and 75·3% of participants were white, 6·3% were Asian, 1·5% were black, 0·05% were mixed, and 4·6% were self-defined as a different ethnicity. Of 6,482 submitted patients meeting pure tone audiometric thresholds for cochlear implantation, 311 already had a cochlear implant. Of the remaining 6,171, 35.7% were informed they were eligible for an implant, but only 9.7% were referred for assessment. When adjusted for site- and patient-specific factors, stand-out findings included that adults were less likely to be referred if they lived in more deprived area decile within Indices of Multiple Deprivation (4th (odds ratio (OR): 2·19; 95% confidence interval (CI): [1·31, 3·66]; p = 0·002), 5th (2·02; [1·21, 3·38]; p = 0·05), 6th (2·32; [1·41, 3·83]; p = 0.05), and 8th (2·07; [1·25, 3·42]; p = 0·004)), lived in London (0·40; [0·29, 0·57]; p < 0·001), were male (females 1·52; [1·27, 1·81]; p < 0·001), or were older (0·97; [0·96, 0·97]; p < 0·001). They were less likely to be informed of their potential eligibility if they lived in more deprived areas (4th (1·99; [1·49, 2·66]; p < 0·001), 5th (1·75; [1·31, 2·33], p < 0·001), 6th (1·85; [1·39, 2·45]; p < 0·001), 7th (1·66; [1·25, 2·21]; p < 0·001), and 8th (1·74; [1·31, 2·31]; p < 0·001) deciles), the North of England or London (North 0·74; [0·62, 0·89]; p = 0·001; London 0·44; [0·35, 0·56]; p < 0·001), were of Asian or black ethnic backgrounds compared to white patients (Asian 0·58; [0·43, 0·79]; p < 0·001; black 0·56; [0·34, 0·92]; p = 0·021), were male (females 1·46; [1·31, 1·62]; p < 0·001), or were older (0·98; [0·98, 0·98]; p < 0·001). The study methodology was limited by its observational nature, reliance on accurate documentation of the referring service, and potential underrepresentation of certain demographic groups. CONCLUSIONS: The majority of adults meeting pure tone audiometric threshold criteria for cochlear implantation are currently not appropriately referred for assessment. There is scope to target underrepresented patient groups to improve referral rates. Future research should engage stakeholders to explore the reasons behind the disparities. Implementing straightforward measures, such as educational initiatives and automated pop-up tools for immediate identification, can help streamline the referral process.
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Implantación Coclear , Implantes Cocleares , Pérdida Auditiva Sensorineural , Pérdida Auditiva , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Pérdida Auditiva Sensorineural/cirugía , Pérdida Auditiva/cirugía , EscolaridadRESUMEN
BACKGROUND: Variations in climate have been associated with a greater risk of surgical site infections, urinary tract infections, and changes in the skin microbiome; however, limited data exist on the impact of climate on inflatable penile prosthesis (IPP) infections. AIM: We sought to evaluate the impact of climate on the risk of IPP infections in a large international, multicenter cohort. METHODS: We performed a multi-institutional, retrospective study of patients undergoing IPP surgery. We then evaluated whether the month or season, during which surgery was performed, affected device infections. Implant infections were defined as infections requiring device explantation. A univariate logistic regression analysis was undertaken. OUTCOMES: Our primary outcome was implant infection. RESULTS: A total of 5289 patients with a mean age of 62.2 ± 10.8 years received IPP placement. There was a fairly even distribution of implants performed in each season. A total of 103 (1.9%) infections were recorded. There were 32 (31.1%) IPP infections in patients who underwent surgery in the summer, followed by 28 (27.2%) in the winter, 26 (25.2%) in the spring, and 17 (16.5%) in the fall. No statistically significant differences were recorded in terms of season (P = .19) and month (P = .29). The mean daily temperature (P = .43), dew point (P = .43), and humidity (P = .92) at the time of IPP placement was not associated with infection. CLINICAL IMPLICATIONS: These findings provide reassurance to prosthetic urologists that infection reduction strategies do not need to be tailored to local climate. STRENGTHS AND LIMITATIONS: Climate data were not directly recorded for each hospital, but rather based on the monthly averages in the city where the surgery was performed. CONCLUSION: The climate at time of IPP placement and time of year of surgery is not associated with IPP infection risk.
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Prótesis de Pene , Infecciones Relacionadas con Prótesis , Humanos , Masculino , Persona de Mediana Edad , Prótesis de Pene/efectos adversos , Estudios Retrospectivos , Infecciones Relacionadas con Prótesis/epidemiología , Infecciones Relacionadas con Prótesis/etiología , Anciano , Estaciones del Año , Temperatura , Implantación de Pene/efectos adversos , Clima , Factores de RiesgoRESUMEN
This autobiographical essay traces my personal journey from grandson of a slave to a cultural psychologist examining racism. My journey includes growing up in a small Ohio town, training in social psychology, and an academic career that was launched with the publication of Prejudice and Racism in 1972. I weave my personal experiences with my analytical approach to racism that incorporates individual, institutional, and cultural factors that combine to explain systemic racism. The racism analysis is balanced by a narrative of mechanisms that confer resilience and psychological well-being on Black people as they navigate the obstacles of systemic racism. I also explore diversity as a form of psychological and behavioral competence required to live effectively in a diverse world. I conclude that these aspects of human relations can be better understood and addressed with advancement of diversity science.
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Racismo , Resiliencia Psicológica , Humanos , Racismo Sistemático , Población Negra , Psicología SocialRESUMEN
BACKGROUND: Real-time surveillance of emerging infectious diseases necessitates a dynamically evolving, computable case definition, which frequently incorporates symptom-related criteria. For symptom detection, both population health monitoring platforms and research initiatives primarily depend on structured data extracted from electronic health records. OBJECTIVE: This study sought to validate and test an artificial intelligence (AI)-based natural language processing (NLP) pipeline for detecting COVID-19 symptoms from physician notes in pediatric patients. We specifically study patients presenting to the emergency department (ED) who can be sentinel cases in an outbreak. METHODS: Subjects in this retrospective cohort study are patients who are 21 years of age and younger, who presented to a pediatric ED at a large academic children's hospital between March 1, 2020, and May 31, 2022. The ED notes for all patients were processed with an NLP pipeline tuned to detect the mention of 11 COVID-19 symptoms based on Centers for Disease Control and Prevention (CDC) criteria. For a gold standard, 3 subject matter experts labeled 226 ED notes and had strong agreement (F1-score=0.986; positive predictive value [PPV]=0.972; and sensitivity=1.0). F1-score, PPV, and sensitivity were used to compare the performance of both NLP and the International Classification of Diseases, 10th Revision (ICD-10) coding to the gold standard chart review. As a formative use case, variations in symptom patterns were measured across SARS-CoV-2 variant eras. RESULTS: There were 85,678 ED encounters during the study period, including 4% (n=3420) with patients with COVID-19. NLP was more accurate at identifying encounters with patients that had any of the COVID-19 symptoms (F1-score=0.796) than ICD-10 codes (F1-score =0.451). NLP accuracy was higher for positive symptoms (sensitivity=0.930) than ICD-10 (sensitivity=0.300). However, ICD-10 accuracy was higher for negative symptoms (specificity=0.994) than NLP (specificity=0.917). Congestion or runny nose showed the highest accuracy difference (NLP: F1-score=0.828 and ICD-10: F1-score=0.042). For encounters with patients with COVID-19, prevalence estimates of each NLP symptom differed across variant eras. Patients with COVID-19 were more likely to have each NLP symptom detected than patients without this disease. Effect sizes (odds ratios) varied across pandemic eras. CONCLUSIONS: This study establishes the value of AI-based NLP as a highly effective tool for real-time COVID-19 symptom detection in pediatric patients, outperforming traditional ICD-10 methods. It also reveals the evolving nature of symptom prevalence across different virus variants, underscoring the need for dynamic, technology-driven approaches in infectious disease surveillance.
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Biovigilancia , COVID-19 , Médicos , SARS-CoV-2 , Estados Unidos , Humanos , Niño , Inteligencia Artificial , Estudios Retrospectivos , COVID-19/diagnóstico , COVID-19/epidemiologíaRESUMEN
PURPOSE: Our aim was to determine if the AUA-recommended prophylaxis (vancomycin + gentamicin alone) for primary inflatable penile prosthesis surgery is associated with a higher infection risk than nonstandard regimens. MATERIALS AND METHODS: We performed a multicenter, retrospective study of patients undergoing primary inflatable penile prosthesis surgery. Patients were divided into those receiving vancomycin + gentamicin alone and those receiving any other regimen. A Cox proportional-hazards model was constructed adjusted for major predictors. A subgroup analysis to identify the appropriate dosage of gentamicin was also performed. RESULTS: A total of 4,161 patients underwent primary inflatable penile prosthesis placement (2,411 received vancomycin + gentamicin alone and 1,750 received other regimens). The infection rate was similar between groups, 1% vs 1.2% for standard vs nonstandard prophylaxis. In the multivariable analysis, vancomycin + gentamicin (HR: 2.7, 95% CI: 1.4 to 5.4, P = .004) and diabetes (HR: 1.9, 95% CI: 1.03 to 3.4, P = .04) were significantly associated with a higher risk of infection. Antifungals (HR: 0.08, 95% CI: 0.03 to 0.19, P < .001) were associated with lower risk of infection. There was no statistically significant difference in infection rate between weight-based gentamicin compared to 80 mg gentamicin (HR: 2.9, 95% CI: 0.83 to 10, P = .1). CONCLUSIONS: Vancomycin + gentamicin alone for antibiotic prophylaxis for primary inflatable penile prosthesis surgery is associated with a higher infection risk than nonstandard antibiotic regimens while antifungal use is associated with lower infection risk. A critical review of the recommended antimicrobial prophylactic regimens is needed. Prospective research is needed to further elucidate best practices in inflatable penile prosthesis antimicrobial prophylaxis.
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Disfunción Eréctil , Implantación de Pene , Prótesis de Pene , Masculino , Humanos , Profilaxis Antibiótica , Vancomicina/uso terapéutico , Estudios Retrospectivos , Estudios Prospectivos , Complicaciones Posoperatorias/cirugía , Prótesis de Pene/efectos adversos , Gentamicinas/uso terapéutico , Disfunción Eréctil/cirugía , Estudios Multicéntricos como AsuntoRESUMEN
BACKGROUND: Corporal fibrosis is known to result from prolonged priapism; however, the impact of the timing of penile prosthesis placement after priapism on complication rates is poorly understood. AIM: We sought to evaluate the impact of timing of inflatable penile prosthesis (IPP) placement on complications in men with a history of ischemic priapism. METHODS: We performed a multicenter, retrospective cohort study of patients with a history of priapism undergoing IPP placement by 10 experienced implantation surgeons. We defined early placement as ≤6 months from priapism to IPP. We identified a 1:1 propensity-matched group of men without a history of priapism and compared complication rates between men who had early placement, late placement, and no history of priapism. OUTCOMES: Our primary outcome was postoperative noninfectious complications, and secondary outcomes included intraoperative complications and postoperative infection. RESULTS: A total of 124 men were included in the study with a mean age of 50.3 ± 12.7 years. A total of 62 had a history of priapism and 62 were matched control subjects. The median duration of priapism was 37 (range, 3-168) hours and the median time from ischemic priapism to IPP placement was 15 months (range, 3 days to 23 years). Fifteen (24%) men underwent early (≤6 months) IPP placement at a median time of 2 months (range, 3 days to 6 months) following the ischemic priapism event. The remaining 47 (76%) underwent placement >6 months following priapism at a median time of 31.5 months (range, 7 months to 23 years). The complication rate in the delayed placement group was 40.5% compared with 0% in the early placement group and control group. Cylinder-related complications such as migration or leak accounted for 8 (57%) of 14 of the postoperative noninfectious complications. Full-sized cylinders were used in all patients who had a cylinder related complication. CLINICAL IMPLICATIONS: Priapism patients should be referred to prosthetic experts early to decrease complication rates in those needing an IPP. STRENGTHS AND LIMITATIONS: This is a multicenter study from experienced prosthetic urologists but is limited by the retrospective nature and small number of patients in the early placement group. CONCLUSION: IPP complication rates are high in men with a history of ischemic priapism, especially when implantation is delayed beyond 6 months.
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Disfunción Eréctil , Implantación de Pene , Prótesis de Pene , Priapismo , Masculino , Humanos , Adulto , Persona de Mediana Edad , Femenino , Estudios Retrospectivos , Prótesis de Pene/efectos adversos , Priapismo/etiología , Priapismo/cirugía , Implantación de Pene/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Disfunción Eréctil/etiologíaRESUMEN
Success in septorhinoplasty surgery can be difficult to assess due to a lack of objective and measurable outcomes. If patients' expectations are not met, it places surgeons performing septorhinoplasty at risk of litigation which can be stressful and costly. The National Institute of health (NHS) Resolution is a government-funded organization in the United Kingdom that provides expertise to the NHS on resolving patient concerns. Data were requested from NHS Resolution for claims involving septorhinoplasty surgery over a period of 5 years between April 2015 and April 2020. Rhinoplasty claims performed by all specialties were included. Data included the claim status, incident details, alleged injury, damages claimed, and damages paid. A total of 31 claims were identified by the study, equating to a total cost of £1,347,336.10. Of the 31 claims for rhinoplasty or septorhinoplasty, 9 cases were open (29%, £962,361.00) and 22 cases were closed (71%, £384,975.10). The common causes for claims were "intraoperative problems (32%)," "failure to warn-informed consent (19%)," and "foreign body left in situ (13%)." The most common injuries were "cosmetic disfigurement (39%)," "unnecessary pain (29%)," and "additional/ unnecessary operation (29%)." This study highlights the need for improved awareness of clinical negligence claims among surgeons who perform septorhinoplasty. Results are applicable to all specialties who perform the procedure. The study highlights the importance of assessing patients' motives and expectations prior to surgery and emphasizes the need for a well-documented rigorous consent process.
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Mala Praxis , Rinoplastia , Humanos , Medicina Estatal , Rinoplastia/efectos adversos , Reino Unido , Consentimiento InformadoRESUMEN
By structuring information in a systematic relational framework, narratives are cultural attractors that are particularly well-suited for transmission. The relational structure of narrative is partly what communicates causality, but this structure also complicates both transmission and selection on cultural elements by introducing correlations among narrative elements and between different narratives. These correlations have implications for adaptation, complexity, and robustness.
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Narración , HumanosRESUMEN
BACKGROUND: Surgery for renal cell carcinoma (RCC) with venous tumour thrombus (VTT) extension into the renal vein (RV) and/or inferior vena cava (IVC) has high peri-surgical morbidity/mortality. NAXIVA assessed the response of VTT to axitinib, a potent tyrosine kinase inhibitor. METHODS: NAXIVA was a single-arm, multi-centre, Phase 2 study. In total, 20 patients with resectable clear cell RCC and VTT received upto 8 weeks of pre-surgical axitinib. The primary endpoint was percentage of evaluable patients with VTT improvement by Mayo level on MRI. Secondary endpoints were percentage change in surgical approach and VTT length, response rate (RECISTv1.1) and surgical morbidity. RESULTS: In all, 35% (7/20) patients with VTT had a reduction in Mayo level with axitinib: 37.5% (6/16) with IVC VTT and 25% (1/4) with RV-only VTT. No patients had an increase in Mayo level. In total, 75% (15/20) of patients had a reduction in VTT length. Overall, 41.2% (7/17) of patients who underwent surgery had less invasive surgery than originally planned. Non-responders exhibited lower baseline microvessel density (CD31), higher Ki67 and exhausted or regulatory T-cell phenotype. CONCLUSIONS: NAXIVA provides the first Level II evidence that axitinib downstages VTT in a significant proportion of patients leading to reduction in the extent of surgery. CLINICAL TRIAL REGISTRATION: NCT03494816.
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Axitinib , Carcinoma de Células Renales , Neoplasias Renales , Trombosis , Axitinib/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/cirugía , Humanos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/cirugía , Terapia Neoadyuvante , Nefrectomía , Estudios Retrospectivos , Trombosis/prevención & controlRESUMEN
BACKGROUND: Predicting the phenotype from the genotype is one of the major contemporary challenges in biology. This challenge is greater in plants because their development occurs mostly post-embryonically under diurnal and seasonal environmental fluctuations. Most current crop simulation models are physiology-based models capable of capturing environmental fluctuations but cannot adequately capture genotypic effects because they were not constructed within a genetics framework. RESULTS: We describe the construction of a mixed-effects dynamic model to predict time-to-flowering in the common bean (Phaseolus vulgaris L.). This prediction model applies the developmental approach used by traditional crop simulation models, uses direct observational data, and captures the Genotype, Environment, and Genotype-by-Environment effects to predict progress towards time-to-flowering in real time. Comparisons to a traditional crop simulation model and to a previously developed static model shows the advantages of the new dynamic model. CONCLUSIONS: The dynamic model can be applied to other species and to different plant processes. These types of models can, in modular form, gradually replace plant processes in existing crop models as has been implemented in BeanGro, a crop simulation model within the DSSAT Cropping Systems Model. Gene-based dynamic models can accelerate precision breeding of diverse crop species, particularly with the prospects of climate change. Finally, a gene-based simulation model can assist policy decision makers in matters pertaining to prediction of food supplies.
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Phaseolus , Fitomejoramiento , Simulación por Computador , Genotipo , Phaseolus/genética , FenotipoRESUMEN
An important role of pH homeostasis has been suggested in the physiology of panic disorder, with acidosis as an interoceptive trigger leading to fear and panic. Identification of novel mechanisms that can translate acidosis into fear will promote a better understanding of panic physiology. The current study explores a role of the subfornical organ (SFO), a blood-brain barrier compromised brain area, in translating acidosis to fear-relevant behaviors. We performed SFO-targeted acidification in male, wild-type mice and mice lacking microglial acid-sensing G protein-coupled receptor-T-cell death-associated gene 8 (TDAG8). Localized SFO acidification evoked significant freezing and reduced exploration that was dependent on the presence of acid-sensor TDAG8. Acidosis promoted the activation of SFO microglia and neurons that were absent in TDAG8-deficient mice. The assessment of regional neuronal activation in wild-type and TDAG8-deficient mice following SFO acidification revealed significant acidosis and genotype-dependent alterations in the hypothalamus, amygdala, prefrontal cortex, and periaqueductal gray nuclei. Furthermore, mapping of interregional co-activation patterns revealed that SFO acidosis promoted positive hypothalamic-cortex associations and desynchronized SFO-cortex and amygdala-cortex associations, suggesting an interplay of homeostatic and fear regulatory areas. Importantly, these alterations were not evident in TDAG8-deficient mice. Overall, our data support a regulatory role of subfornical organ microglial acid sensing in acidosis-evoked fear, highlighting a centralized role of blood-brain barrier compromised nodes in interoceptive sensing and behavioral regulation. Identification of pathways by which humoral information can modulate fear behavior is relevant to panic disorder, where aberrant interoceptive signaling has been reported.
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Acidosis , Órgano Subfornical , Acidosis/metabolismo , Animales , Miedo , Masculino , Ratones , Microglía/metabolismo , Prosencéfalo , Órgano Subfornical/metabolismoRESUMEN
The origins of the high-energy cosmic neutrino flux remain largely unknown. Recently, one high-energy neutrino was associated with a tidal disruption event (TDE). Here we present AT2019fdr, an exceptionally luminous TDE candidate, coincident with another high-energy neutrino. Our observations, including a bright dust echo and soft late-time x-ray emission, further support a TDE origin of this flare. The probability of finding two such bright events by chance is just 0.034%. We evaluate several models for neutrino production and show that AT2019fdr is capable of producing the observed high-energy neutrino, reinforcing the case for TDEs as neutrino sources.
RESUMEN
Epidemics may pose a significant dilemma for governments and individuals. The personal or public health consequences of inaction may be catastrophic; but the economic consequences of drastic response may likewise be catastrophic. In the face of these trade-offs, governments and individuals must therefore strike a balance between the economic and personal health costs of reducing social contacts and the public health costs of neglecting to do so. As risk of infection increases, potentially infectious contact between people is deliberately reduced either individually or by decree. This must be balanced against the social and economic costs of having fewer people in contact, and therefore active in the labor force or enrolled in school. Although the importance of adaptive social contact on epidemic outcomes has become increasingly recognized, the most important properties of coupled human-natural epidemic systems are still not well understood. We develop a theoretical model for adaptive, optimal control of the effective social contact rate using traditional epidemic modeling tools and a utility function with delayed information. This utility function trades off the population-wide contact rate with the expected cost and risk of increasing infections. Our analytical and computational analysis of this simple discrete-time deterministic strategic model reveals the existence of an endemic equilibrium, oscillatory dynamics around this equilibrium under some parametric conditions, and complex dynamic regimes that shift under small parameter perturbations. These results support the supposition that infectious disease dynamics under adaptive behavior change may have an indifference point, may produce oscillatory dynamics without other forcing, and constitute complex adaptive systems with associated dynamics. Implications for any epidemic in which adaptive behavior influences infectious disease dynamics include an expectation of fluctuations, for a considerable time, around a quasi-equilibrium that balances public health and economic priorities, that shows multiple peaks and surges in some scenarios, and that implies a high degree of uncertainty in mathematical projections.
Asunto(s)
COVID-19/epidemiología , COVID-19/prevención & control , Salud Pública , Conducta Social , Simulación por Computador , Trazado de Contacto , Susceptibilidad a Enfermedades , Epidemias , Humanos , Modelos Biológicos , Oscilometría , RiesgoRESUMEN
BACKGROUND: Changes in anorectal sensation have been reported in patients with fecal incontinence, and there is limited evidence that sacral nerve stimulation can restore normal sensation. OBJECTIVE: The aims of the present study were to investigate changes in the transmission of sensory anorectal stimuli in a rodent model of fecal incontinence and to study the effects of sacral nerve stimulation on defecation behavior. DESIGN: An established model of fecal incontinence was utilized for this study. INTERVENTION: Pudendal nerve stretch and compression were used in 16 adult female Wistar rats and were monitored for 3 weeks: 6 rats received sacral nerve stimulation for 1 week by using an implantable neurostimulator and 10 rats had nonfunctioning "dummy" devices inserted. Five additional rats were sham operated. Anorectal cortical evoked potentials were used as a surrogate marker for anorectal sensory function. MAIN OUTCOME MEASURES: The primary outcomes measured were fecal incontinence index, evoked potential amplitude, and latency. RESULTS: Fifty percent of rats showed behavioral signs of fecal incontinence measured by the Fecal Incontinence Index (>0.20), calculated by using the pellet distribution outside the cage's latrine area. Anorectal evoked potential amplitude was reduced in rats with a Fecal Incontinence Index >0.20 (p = 0.019). The amplitude of forepaw evoked potentials recorded as a control was not different between groups. Chronic sacral nerve stimulation using the fully implantable device and custom rodent lead was safe and stable during this chronic prospective study. Incontinent rats (n = 3) that received sacral nerve stimulation showed an improvement of Fecal Incontinence Index and an increase of evoked potential amplitude to anorectal stimulation compared with the dummy implant controls (n = 5). LIMITATIONS: The main limitation is the small number of animals that received sacral nerve stimulation. CONCLUSIONS: Chronic sacral nerve stimulation is feasible in rats when miniature telemetric devices are used. Behavioral signs of fecal incontinence were positively correlated with the latency of anorectal evoked potentials. See Video Abstract at http://links.lww.com/DCR/B712.RELACIÓN ENTRE LA ACTIVACIÓN CORTICAL EN RESPUESTA A LOS ESTÍMULOS ANORRECTALES Y EL COMPORTAMIENTO DE CONTINENCIA EN RATAS QUE SE COMPORTAN LIBREMENTE ANTES Y DESPUÉS DE LA APLICACIÓN DE ESTIMULACIÓN DEL NERVIO SACRO. ANTECEDENTES: Se han informado cambios en la sensación anorrectal en pacientes con incontinencia fecal y hay evidencia limitada de que la estimulación del nervio sacro puede restaurar la sensación normal. OBJETIVO: Los objetivos del presente estudio fueron investigar los cambios en la transmisión de estímulos anorrectales sensoriales en un modelo de roedor de incontinencia fecal y estudiar los efectos de la estimulación del nervio sacro en la conducta de defecación. DISEO: Un modelo establecido de incontinencia fecal. INTERVENCIN: Se utilizó estiramiento y compresión del nervio pudendo en 16 ratas Wistar hembras adultas y se les realizó un seguimiento durante 3 semanas: seis ratas recibieron estimulación del nervio sacro durante 1 semana utilizando un neuroestimulador implantable y diez ratas tuvieron insertados dispositivos "ficticios" no funcionantes. Se operaron simuladamente cinco ratas adicionales. Los potenciales evocados corticales anorrectales se utilizaron como marcador subrogado de la función sensorial anorrectal. PRINCIPALES MEDIDAS DE RESULTADO: Índice de incontinencia fecal, amplitud de potenciales evocados y latencia. RESULTADOS: El cincuenta por ciento de las ratas mostró signos de comportamiento de incontinencia fecal medidos por el Índice de incontinencia fecal (> 0.20), calculado utilizando la distribución de heces fuera del área de la letrina de la jaula. La amplitud del potencial evocado anorrectal se redujo en ratas con un índice de incontinencia fecal >0.20 (p = 0.019). La amplitud de los potenciales evocados de la pata delantera registrados como control no fue diferente entre los grupos. La estimulación crónica del nervio sacro utilizando un dispositivo totalmente implantable y un cable de roedor personalizado fue segura y estable durante este estudio prospectivo crónico. Las ratas con incontinencia (N = 3) que recibieron estimulación del nervio sacro mostraron una mejora del índice de incontinencia fecal y un aumento de la amplitud del potencial evocado a la estimulación anorrectal en comparación con los controles de implante ficticio (N = 5). LIMITACIONES: La principal limitación es el pequeño número de animales que recibieron estimulación del nervio sacro. CONCLUSIONES: La estimulación crónica del nervio sacro es factible en ratas cuando se utilizan dispositivos telemétricos en miniatura. Los signos conductuales de incontinencia fecal se correlacionaron positivamente con la latencia de los potenciales evocados anorrectales. Consulte Video Resumen en http://links.lww.com/DCR/B712. (Traducción-Dr. Jorge Silva Velazco).
Asunto(s)
Excitabilidad Cortical/fisiología , Terapia por Estimulación Eléctrica/instrumentación , Conducta Excretoria Animal/fisiología , Incontinencia Fecal/fisiopatología , Incontinencia Fecal/terapia , Nervios Espinales , Animales , Modelos Animales de Enfermedad , Incontinencia Fecal/psicología , Femenino , Neuroestimuladores Implantables , Ratas , Ratas WistarRESUMEN
INTRODUCTION: Abdominal aortic aneurysm (AAA) repair may be performed through open or endovascular approaches, but the factors influencing a patient's repair-type preference are not well characterized. Here we performed a qualitative analysis to better understand factors influencing patient preference within the Preference for Open Versus Endovascular Repair of AAA Trial. METHODS: Open-ended responses regarding primary (n = 21) and secondary (n = 47) factors influencing patient preference underwent qualitative analysis using the constant comparative method with iterative reviews. Codes were used to generate themes and themes grouped into categories, with each step conducted via consensus agreement between three researchers. Relative prevalence of themes were compared to ascertain trends in patient preference. RESULTS: Patient responses regarding both primary and secondary factors fell into four categories: Short-term concerns, long-term concerns, advice & experience, and other. Patients most frequently described short-term concerns (23) as their primary influence, with themes including post-op complications, hospitalization & recovery, and intraoperative concerns. Long-term concerns were more prevalent (20) as secondary factors, which included themes such as survival, and chronic management. The average age of patients voicing only long-term concerns as a primary factor was 11 years younger than those listing only short-term concerns. CONCLUSION: Short-term concerns relating to the procedure and recovery are more often the primary factor influencing patient preference, while long term concerns play a more secondary role. Long-term concerns are more often a primary factor in younger patients. Vascular surgeons should consider this information in shared decision making to reach an optimal outcome.