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1.
Nature ; 617(7959): 55-60, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37138107

RESUMO

Planets with short orbital periods (roughly under 10 days) are common around stars like the Sun1,2. Stars expand as they evolve and thus we expect their close planetary companions to be engulfed, possibly powering luminous mass ejections from the host star3-5. However, this phase has never been directly observed. Here we report observations of ZTF SLRN-2020, a short-lived optical outburst in the Galactic disk accompanied by bright and long-lived infrared emission. The resulting light curve and spectra share striking similarities with those of red novae6,7-a class of eruptions now confirmed8 to arise from mergers of binary stars. Its exceptionally low optical luminosity (approximately 1035 erg s-1) and radiated energy (approximately 6.5 × 1041 erg) point to the engulfment of a planet of fewer than roughly ten Jupiter masses by its Sun-like host star. We estimate the Galactic rate of such subluminous red novae to be roughly between 0.1 and several per year. Future Galactic plane surveys should routinely identify these, showing the demographics of planetary engulfment and the ultimate fate of planets in the inner Solar System.

2.
Circulation ; 149(1): e1-e156, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38033089

RESUMO

AIM: The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation. METHODS: A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate. STRUCTURE: Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.


Assuntos
Fibrilação Atrial , Cardiologia , Tromboembolia , Humanos , American Heart Association , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Fatores de Risco , Estados Unidos/epidemiologia
3.
Histopathology ; 84(7): 1224-1237, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38422618

RESUMO

AIMS: Liquid biopsy (LBx)-based next-generation sequencing (NGS) of circulating tumour DNA (ctDNA) can facilitate molecular profiling of haematopoietic neoplasms (HNs), particularly when tissue-based NGS is infeasible. METHODS AND RESULTS: We studied HN LBx samples tested with FoundationOne Liquid CDx, FoundationOne Liquid, or FoundationACT between July 2016 and March 2022. We identified 271 samples: 89 non-Hodgkin lymphoma (NHL), 43 plasma-cell neoplasm (PCN), 41 histiocytoses, 27 myelodysplastic syndrome (MDS), 25 diffuse large B-cell lymphoma (DLBCL), 22 myeloproliferative neoplasm (MPN), 14 Hodgkin lymphoma (HL), and 10 acute myeloid leukaemia (AML). Among 73.4% with detectable pathogenic alterations, median maximum somatic allele frequency (MSAF) was 16.6%, with AML (36.2%), MDS (19.7%), and MPN (44.5%) having higher MSAFs than DLBCL (3.9%), NHL (8.4%), HL (1.5%), PCN (2.8%), and histiocytoses (1.8%) (P = 0.001). LBx detected characteristic alterations across HNs, including in TP53, KRAS, MYD88, and BTK in NHLs; TP53, KRAS, NRAS, and BRAF in PCNs; IGH in DLBCL; TP53, ATM, and PDCD1LG2 in HL; BRAF and MAP2K1 in histiocytoses; TP53, SF3B1, DNMT3A, TET2, and ASXL1 in MDS; JAK2 in MPNs; and FLT3, IDH2, and NPM1 in AML. Among 24 samples, the positive percent agreement by LBx was 75.7% for variants present in paired buffy coat, marrow, or tissues. Also, 75.0% of pairs exhibited alterations only present on LBx. These were predominantly subclonal (clonal fraction of 3.8%), reflecting the analytical sensitivity of LBx. CONCLUSION: These data demonstrate that LBx can detect relevant genomic alterations across HNs, including at low clonal fractions, suggesting a potential clinical utility for identifying residual or emerging therapy-resistant clones that may be undetectable in site-specific tissue biopsies.


Assuntos
Biomarcadores Tumorais , DNA Tumoral Circulante , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Biópsia Líquida , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/análise , Biomarcadores Tumorais/genética , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Adulto , Mutação , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Neoplasias Hematológicas/diagnóstico , Nucleofosmina , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/patologia , Transtornos Mieloproliferativos/sangue
4.
J Cardiovasc Pharmacol ; 83(1): 16-22, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815234

RESUMO

ABSTRACT: Sepsis and septic shock are life-threatening conditions that are associated with high mortality and considerable health care costs. The association between prior angiotensin-converting enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARBs) use and outcomes after sepsis is elusive. The aim of this study was to evaluate the role of the prior use of ACEi or ARBs and outcomes after sepsis and septic shock. A relevant literature review was performed in 4 databases from inception until July 2022. Independent reviewers first screened the title, abstract, and full text, and then, data extraction and analysis were performed. One post hoc analysis of a trial and 6 retrospective cohort studies were included in this review. There were 22% lower odds of in-hospital/30-day mortality among patients who have used ACEi/ARBs in the past [23.83% vs. 37.20%; odds ratio (OR), 0.78, 95% confidence interval (CI), 0.64-0.96], and reduced 90-day mortality (OR, 0.80, 95% CI, 0.69-0.92). ACEi/ARBs users were found to have 31% lesser odds of developing acute kidney injury as compared with nonusers (OR, 0.69, 95% CI, 0.63-0.76). There was no significant difference in the length of hospital stay (MD 1.26, 95% CI, ‒7.89 to 10.42), need for renal replacement therapy (OR, 0.71, 95% CI, 0.13-3.92), mechanical ventilation (OR, 1.10, 95% CI, 0.88-1.37) or use of vasopressors (OR, 1.21, 95% CI, 0.91-1.61). Based on this analysis, prior use of ACEi/ARBs lowers the risk of mortality and adverse renal events in patients with sepsis and septic shock.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Choque Séptico , Humanos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Antagonistas de Receptores de Angiotensina/efeitos adversos , Choque Séptico/diagnóstico , Choque Séptico/tratamento farmacológico , Estudos Retrospectivos , Rim
5.
Graefes Arch Clin Exp Ophthalmol ; 262(3): 813-822, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37955702

RESUMO

PURPOSE: The purpose of this study is to investigate test-retest reliability and agreement of the quantitative contrast sensitivity function test (qCSF) in the retina clinic. METHODS: A total of 121 right eyes of 121 patients were tested and consecutively re-tested with qCSF in the retina clinic. Outcomes included area under the logarithm of contrast sensitivity function curve (AULCSF), contrast acuity, and contrast sensitivity thresholds at 1-18 cycles per degree (cpd). Test-retest means were compared with paired t-test, variability was compared with the Brown-Forsythe test, and intraclass correlation coefficient (ICC) and Bland Altman plots evaluated reliability and agreement. RESULTS: Mean test-retest differences for all qCSF metrics ranged from 0.02 to 0.05 log units without statistically significant differences in variability. Standard deviations ranged from 0.08 to 0.14. Coefficients of repeatability ranged from 0.16 to 0.27 log units. ICC > 0.9 for all metrics except 1cpd (ICC = 0.84, all p < 0.001); AULCSF ICC = 0.971. CONCLUSION: qCSF-measured contrast sensitivity shows great test-retest repeatability and agreement in the retina clinic.


Assuntos
Sensibilidades de Contraste , Testes Visuais , Humanos , Reprodutibilidade dos Testes , Retina
6.
Artigo em Inglês | MEDLINE | ID: mdl-38376563

RESUMO

PURPOSE: To investigate the impact of anti-VEGF therapy on vascular metrics in eyes with macular edema secondary to central retinal vein occlusion (CRVO) using wider field swept-source OCT angiography (WF SS-OCTA). METHODS: We included 23 eyes with macular edema associated with non-ischemic CRVO from 22 patients treated with anti-VEGF therapy (median number of injections: 5 [2-9]). Changes in vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ) parameters were measured using WF SS-OCTA. Visual acuity (VA) and central subfield thickness (CST) were also measured. RESULTS: Median CST decreased significantly from 369 µm (305-531) to 267 µm (243-300, p < 0.001). VD and VSD parameters in 12 × 12 mm images showed significant reductions. For instance, VSD in the whole retina decreased from a median of 13.37 (11.22-13.74) to 11.29 (9.36-12.97, p = 0.013). Additionally, a significant increase in FAZ circularity was found, suggesting improved microvascular integrity. Significant inverse correlations were found between the number of anti-VEGF injections and all VSD and VD parameters on the 12 × 12 mm images (p < 0.05). Notably, the reductions in VSD and VD on 12 × 12 mm angiograms in the deep capillary plexus (DCP) after each injection significantly correlated with increased logMAR VA (worse VA). CONCLUSION: Anti-VEGF therapy in CRVO patients not only mitigates macular edema but also alters the overall microvascular morphology and functionality as revealed by WF SS-OCTA.

7.
Luminescence ; 39(1): e4622, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37950516

RESUMO

A series of tungstate double perovskite Ca3 WO6 doped with Tb3+ was prepared by a combustion process using urea as a flux. The crystal structure identification of Ca3 WO6 :Tb3+ phosphors was done using X-ray diffraction patterns, and a monoclinic structure was discovered. The Fourier transform infrared spectrum of Ca3 WO6 :Tb3+ displayed characteristic vibrations of tungstate bonds. Under 278 nm excitation, Ca3 WO6 :Tb3+ exhibited intense downconversion green emission, which corresponded to the 5 D4 -7 FJ (J = 4,5) transitions of Tb3+ . The phosphor exhibited the highest photoluminescence (PL) intensity when it was doped with 1 mol% of Tb3+ ; later intensity quenching appeared to be due to the multipolar interaction at higher dopant concentrations. Moreover, high-quality thermoluminescence (TL) was detected when phosphors were irradiated using beta rays. The effects of Tb3+ concentration and beta dose on TL intensity were the two major aspects studied in detail. The TL intensity demonstrated excellent linear response to the applied range of beta dose. The trap parameters of the studied phosphors were computed by the peak shape approach and glow curve deconvolution. The fading effect on TL intensity was studied by recording the TL glow curves after 1 month of beta irradiation. Obtained results from the PL and TL characterizations showed that the phosphors under study have the potential to be used in lighting displays and in thermoluminescence dosimetry.


Assuntos
Luminescência , Óxidos , Térbio , Titânio , Compostos de Tungstênio , Compostos de Cálcio , Dosimetria Termoluminescente
8.
Br J Cancer ; 129(3): 383-392, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37258796

RESUMO

Identifying healthy carriers of germline pathogenic variants in high penetrance cancer susceptibility genes offers the potential for risk-reducing surgery. The NHS England National Genomic Test Directory offers germline and somatic testing to patients with certain cancers or rare and inherited diseases, or, in some cases, to their relatives. This review summarises current UK guidelines for risk-reducing surgical interventions available for individuals with no personal history of cancer, who are determined to carry germline pathogenic variants. An electronic literature search of NICE guidelines and PubMed citable articles was performed. NICE guidelines are available for bilateral mastectomy and are currently in development for risk-reducing bilateral salpingo-oophorectomy. Guidelines developed with affiliation to, or through relevant British Surgical Societies or international consensus, are available for risk-reducing hysterectomy, polypectomy, gastrectomy, and thyroidectomy. There is a disparity in the development and distribution of national guidelines for interventions amongst tumour types. Whilst we are focusing on UK guidelines, we anticipate they will be relevant much more generally and so of interest to a wider audience including where there are no national guidelines to refer to. We suggest that, as genetic testing becomes rapidly more accessible, guideline development for interventions should be more closely aligned to those for testing.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Mastectomia , Mutação em Linhagem Germinativa , Testes Genéticos , Reino Unido , Predisposição Genética para Doença
9.
Ophthalmology ; 130(4): 373-378, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36396121

RESUMO

PURPOSE: To compare the types and dosages of anti-vascular endothelial growth factors (VEGFs) to ascertain whether specific dosages or types of injection were associated with retreatment in clinical practice in the United States. DESIGN: Multicenter, retrospective, consecutive series. PARTICIPANTS: Patients with retinopathy of prematurity (ROP) treated with anti-VEGF injections from 2007 to 2021. METHODS: Sixteen sites from the United States participated. Data collected included demographics, birth characteristics, examination findings, type and dose of anti-VEGF treatment, retreatment rates, and time to retreatment. Comparisons of retreatment rates between bevacizumab and ranibizumab intravitreal injections were made. MAIN OUTCOME MEASURES: Relative rate of retreatment between varying types of anti-VEGF therapy, including bevacizumab and ranibizumab, and the various dosages used for each. RESULTS: Data from 873 eyes of 661 patients (61% male and 39% female) were collected. After exclusion of 40 eyes treated with laser before anti-VEGF injection and 266 eyes re-treated with laser at or beyond 8 weeks after the initial anti-VEGF treatment, 567 eyes of 307 patients (63% male and 37% female) remained and were included in the primary analysis. There was no difference between the no retreatment and retreatment groups in terms of birthweight, gestational age, age at first injection, ROP stages, or number of involved clock hours. The retreatment group had a larger percentage of aggressive ROP (34% vs. 18%, P < 0.001) and greater percentage of zone 1 ROP (49 vs. 34%, P = 0.001) than the no retreatment group. Ranibizumab use was associated with a higher rate of retreatment than bevacizumab use (58% vs. 37%, P < 0.001), whereas the rate of retreatment was not associated with a specific dose of ranibizumab (R2 = 0.67, P = 0.32). Meanwhile, lower doses of bevacizumab were associated with higher rates of retreatment compared with the higher doses (R2 = 0.84, P = 0.01). There was a dose-specific trend with higher doses trending toward lower retreatments for bevacizumab. CONCLUSIONS: In a multicenter study of ROP patients initially treated with anti-VEGF therapy, ranibizumab and lower-dose bevacizumab use were associated with an increased rate of retreatment when compared with higher-dose bevacizumab. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Assuntos
Ranibizumab , Retinopatia da Prematuridade , Recém-Nascido , Humanos , Masculino , Feminino , Bevacizumab/uso terapêutico , Ranibizumab/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/diagnóstico , Injeções Intravítreas , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular , Idade Gestacional
10.
Graefes Arch Clin Exp Ophthalmol ; 261(7): 1835-1859, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36680613

RESUMO

PURPOSE: Data from healthy eyes is needed to interpret optical coherence tomography angiography (OCTA) findings. However, very little normative data is available for wide-field swept-source OCTA (WF SS-OCTA), particularly 12 × 12-mm and disc-centered angiograms. Therefore, we aim to report quantitative metrics in a large sample of control eyes. METHODS: In this cross-sectional observational study, 482 eyes of 375 healthy adults were imaged on the 100 kHz Zeiss PLEX® Elite 9000 using protocols centered on the fovea (3 × 3, 6 × 6, and 12 × 12-mm) and optic disc (6 × 6 and 12 × 12-mm) between December 2018 and January 2022. The ARI Network (Zeiss Portal v5.4) was used to calculate vessel density (VD) and vessel skeletonized density (VSD) in the superficial capillary plexus, deep capillary plexus, and whole retina, as well as foveal avascular zone (FAZ) parameters. Mixed-effect multiple linear regression models were used for statistical analysis. RESULTS: The subjects' median age was 55 (38-63) years, and 201 (53.6%) were female. Greater age and worse best-corrected visual acuity (BCVA) were associated with significantly lower VD and VSD (p < 0.05). VD and VSD differed based on race and cataract status, but not sex, on some scan protocols (p < 0.05). FAZ circularity decreased with age, and FAZ dimensions differed based on race and ethnicity in certain scan protocols. CONCLUSIONS: We report a large database of parafoveal and peripapillary vascular metrics in several angiogram sizes. In referencing these values, researchers must consider characteristics such as age, race, and BCVA, but will have a valuable point of comparison for OCTA measurements in pathologic settings.


Assuntos
Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Adulto , Feminino , Pessoa de Meia-Idade , Masculino , Angiofluoresceinografia/métodos , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Estudos Transversais , Benchmarking , Acuidade Visual
11.
Ophthalmic Physiol Opt ; 43(6): 1531-1539, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37401194

RESUMO

PURPOSE: Intracranial pressure increases in head-down tilt (HDT) body posture. This study evaluated the effect of HDT on the optic nerve sheath diameter (ONSD) in normal subjects. METHODS: Twenty six healthy adults (age 28 [4.7] years) participated in seated and 6° HDT visits. For each visit, subjects presented at 11:00 h for baseline seated scans and then maintained a seated or 6° HDT posture from 12:00 to 15:00 h. Three horizontal axial and three vertical axial scans were obtained at 11:00, 12:00 and 15:00 h with a 10 MHz ultrasonography probe on the same eye, randomly chosen per subject. At each time point, horizontal and vertical ONSD (mm) were quantified by averaging three measures taken 3 mm behind the globe. RESULTS: In the seated visit, ONSDs were similar across time (p > 0.05), with an overall mean (standard deviation) of 4.71 (0.48) horizontally and 5.08 (0.44) vertically. ONSD was larger vertically than horizontally at each time point (p < 0.001). In the HDT visit, ONSD was significantly enlarged from baseline at 12:00 and 15:00 h (p < 0.001 horizontal and p < 0.05 vertical). Mean (standard error) horizontal ONSD change from baseline was 0.37 (0.07) HDT versus 0.10 (0.05) seated at 12:00 h (p = 0.002) and 0.41 (0.09) HDT versus 0.12 (0.06) seated at 15:00 h (p = 0.002); mean vertical ONSD change was 0.14 (0.07) HDT versus -0.07 (0.04) seated at 12:00 h (p = 0.02) and 0.19 (0.06) HDT versus -0.03 (0.04) seated at 15:00 h (p = 0.01). ONSD change in HDT was similar between 12:00 and 15:00 h (p ≥ 0.30). Changes at 12:00 h correlated with those at 15:00 h for horizontal (r = 0.78, p < 0.001) and vertical ONSD (r = 0.73, p < 0.001). CONCLUSION: The ONSD increased when body posture transitioned from seated to HDT position without any further change at the end of the 3 h in HDT.


Assuntos
Decúbito Inclinado com Rebaixamento da Cabeça , Nervo Óptico , Adulto , Humanos , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Voluntários Saudáveis , Ultrassonografia , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/fisiologia
12.
Pediatr Radiol ; 53(6): 1163-1170, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36859687

RESUMO

BACKGROUND: Current guidelines recommend healthcare professionals avoid routine use of neuroimaging for diagnosing mild traumatic brain injury (mTBI). OBJECTIVE: This study aimed to examine current use of CT and MRI among children and young adult patients with mTBI and factors that increase likelihood of neuroimaging in this population. MATERIALS AND METHODS: Data were analyzed using the 2019 MarketScan commercial claims and encounters database for the commercially insured population for both inpatient and outpatient claims. Descriptive statistics and logistic regression models for patients ≤24 years of age who received an ICD-10-CM code indicative of a possible mTBI were analyzed. RESULTS: Neuroimaging was performed in 16.9% (CT; 95% CI=16.7-17.1) and 0.9% (MRI; 95% CI=0.8-0.9) of mTBI outpatient visits (including emergency department visits) among children (≤18 years old). Neuroimaging was performed in a higher percentage of outpatient visits for patients 19-24 years old (CT=47.1% [95% CI=46.5-47.6] and MRI=1.7% [95% CI=1.5-1.8]), and children aged 15-18 years old (CT=20.9% [95% CI=20.5-21.2] and MRI=1.4% [95% CI=1.3-1.5]). Outpatient visits for males were 1.22 (95% CI=1.10-1.25) times more likely to include CT compared to females, while there were no differences by sex for MRI or among inpatient stays. Urban residents, as compared to rural, were less likely to get CT in outpatient settings (adjusted odds ratio [aOR]=0.55, 95% CI=0.53-0.57). Rural residents demonstrated a larger proportion of inpatient admissions that had a CT. CONCLUSIONS: Despite recommendations to avoid routine use of neuroimaging for mTBI, neuroimaging remained common practice in 2019.


Assuntos
Concussão Encefálica , Masculino , Feminino , Adulto Jovem , Humanos , Criança , Adulto , Adolescente , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/epidemiologia , Estudos Transversais , Neuroimagem , Imageamento por Ressonância Magnética , Serviço Hospitalar de Emergência
13.
Luminescence ; 38(2): 176-187, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36610019

RESUMO

A luminescent double perovskite phosphor Sr2 YNbO6 doped with Eu3+ crystallized to the monoclinic phase and was synthesized successfully via a conventional high-temperature combustion method. The formation of the crystal structure, phase purity, and surface morphology were studied using X-ray diffraction patterns and scanning electron microscopy. The characteristic vibrations between the atoms of the functional groups present in phosphor were studied using Fourier transform infrared spectra analysis. The luminescence properties of the prepared phosphors were investigated in terms of photoluminescence (PL) and thermoluminescence (TL). PL excitation spectra exhibited charge transfer bands and the characteristic 4f6 transitions of Eu3+ . A prominent PL emission was obtained for the phosphor doped with 4 mol% Eu3+ under the 396 nm excitation wavelength. PL emission quenching was observed for the higher doping concentrations due to a multipole-multipole interaction. A highly intense PL emission arose due to the hypersensitive 5 D0 -7 F2 electric dipole transition of Eu3+ that dominated the emission spectra. The thermal stability of the phosphor was examined through temperature-dependent PL. The TL properties of the Sr2 YNbO6 double perovskites irradiated with a 90 Sr beta source at different doses were measured. The double perovskite phosphors under study showed a linear dose-response with increasing beta dose, ranging from 1 Gy to 10 Gy. Trapping parameters of the TL glow curves were determined using Chen's peak shape method and computerized glow curve deconvolution (CGCD). CGCD fitting of the TL glow curves revealed that it was consisted of three major peaks and followed second-order kinetics. The estimated activation energies were determined using different methods and were comparable and significant.


Assuntos
Európio , Substâncias Luminescentes , Európio/química , Substâncias Luminescentes/química , Compostos de Cálcio , Óxidos , Difração de Raios X , Luminescência
14.
Clin Otolaryngol ; 48(4): 604-612, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36950831

RESUMO

OBJECTIVE: This study aimed to assess if the Hospital Frailty Risk Score (HFRS) could predict outcomes for older people undergoing head and neck procedures. DESIGN: A retrospective cohort study of patients admitted between April 2008 and February 2020, undergoing head and neck procedures defined as major resections using procedural codes. SETTING: The analysis was performed using data from the NHS Secondary Uses Service (SUS) electronic database. PARTICIPANTS: A number of 7479 patients were selected based on an age of 75 years and above and an admission associated with a diagnostic code associated with a head and neck cancer. Based on HFRS, 5153 patients were risk-stratified into mild, moderate, and severe frailty risk. MAIN OUTCOME MEASURES: The relationships between frailty risk and length of stay, readmission rate, and mortality were quantified using descriptive statistics. RESULTS: Severely frail patients had a median length of stay of 9 days compared to 3 for mildly frail patients. Twenty-seven percentage of severely frail patients were readmitted within 30 days of surgery. Rising levels of frailty correlate with a higher risk of death following surgery which is maintained in longer term mortality at 1 year and until the data were extracted in March 2022. Fifty percentage of moderately frail patients and 66% of severely frail patients had died in hospital by the end of the study period. CONCLUSION: The results quantify the relationship between frailty and adverse health outcomes. This information could be used to identify those that might benefit from holistic assessment, aid prognostication, commissioning, and service planning.


Assuntos
Fragilidade , Neoplasias de Cabeça e Pescoço , Humanos , Idoso , Idoso Fragilizado , Estudos Retrospectivos , Fatores de Risco , Hospitais , Tempo de Internação , Complicações Pós-Operatórias
15.
Ophthalmology ; 129(12): 1380-1388, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35863512

RESUMO

PURPOSE: To report practice patterns of intravitreal injections of anti-VEGF for retinopathy of prematurity (ROP) and outcomes data with a focus on retreatments and complications. DESIGN: Multicenter, international, retrospective, consecutive series. SUBJECTS: Patients with ROP treated with anti-VEGF injections from 2007 to 2021. METHODS: Twenfty-three sites (16 United States [US] and 7 non-US) participated. Data collected included demographics, birth characteristics, examination findings, and methods of injections. Comparisons between US and non-US sites were made. MAIN OUTCOME MEASURES: Primary outcomes included number and types of retreatments as well as complications. Secondary outcomes included specifics of the injection protocols, including types of medication, doses, distance from limbus, use of antibiotics, and quadrants where injections were delivered. RESULTS: A total of 1677 eyes of 918 patients (43% female, 57% male) were included. Mean gestational age was 25.7 weeks (range, 21.2-41.5 weeks), and mean birth weight was 787 g (range, 300-2700 g). Overall, a 30-gauge needle was most commonly used (51%), and the quadrant injected was most frequently the inferior-temporal (51.3%). The distance from the limbus ranged from 0.75 to 2 mm, with 1 mm being the most common (65%). Bevacizumab was the most common anti-VEGF (71.4%), with a dose of 0.625 mg in 64% of cases. Overall, 604 (36%) eyes required retreatment. Of those, 79.8% were retreated with laser alone, 10.6% with anti-VEGF injection alone, and 9.6% with combined laser and injection. Complications after anti-VEGF injections occurred in 15 (0.9%) eyes, and no cases of endophthalmitis were reported. Patients in the United States had lower birth weights and gestational ages (665.6 g and 24.5 weeks, respectively) compared with non-US patients (912.7 g and 26.9 weeks, respectively) (P < 0.0001). Retreatment with reinjection and laser was significantly more common in the US compared with the non-US group (8.5% vs. 4.7% [P = 0.0016] and 55% vs. 7.2% [P < 0.001], respectively). There was no difference in the incidence of complications between the 2 geographic subgroups. CONCLUSIONS: Anti-VEGF injections for ROP were safe and well tolerated despite a variance in practice patterns. Infants with ROP receiving injections in the US tended to be younger and smaller, and they were treated earlier with more retreatments than non-US neonates with ROP.


Assuntos
Doenças do Recém-Nascido , Retinopatia da Prematuridade , Humanos , Lactente , Recém-Nascido , Masculino , Feminino , Injeções Intravítreas , Retinopatia da Prematuridade/diagnóstico , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular , Inibidores da Angiogênese , Bevacizumab/uso terapêutico , Idade Gestacional , Anticorpos Monoclonais/uso terapêutico , Peso ao Nascer , Fatores de Crescimento do Endotélio Vascular
16.
J Cardiovasc Pharmacol ; 79(4): 420-430, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34935703

RESUMO

ABSTRACT: Several randomized controlled trials have studied the role of colchicine, a potent anti-inflammatory drug, to prevent adverse cardiovascular events in patients with coronary artery disease (CAD). In this meta-analysis, we aimed to determine the role of colchicine in patients with CAD in clinical outcomes and mortality. We searched PubMed, PubMed Central, Scopus, and Embase for randomized controlled trials/experimental studies evaluating the role of colchicine in patients with CAD. After assessing the eligibility for inclusion, risk-of-bias assessment, and data extraction from the included studies, a narrative synthesis was conducted. Of 17 studies included for the qualitative analysis, 11 studies reported that inflammatory markers such as C-reactive protein and cytokines were reduced in the colchicine group, suggesting an anti-inflammatory role of colchicine in CAD. Quantitative analysis with pooling of data from 9 studies using a fixed-effect model showed 28% lower odds of acute myocardial infarction [odds ratio (OR) 0.72, 95% CI 0.59-0.86; n = 11,712], 52% lower occurrence of stroke (OR 0.48, 95% CI 0.30-0.76), and 37% reduction in odds of coronary revascularization procedure in the colchicine group (OR 0.63, 95% CI 0.52-0.76; n= 11,258). However, the odds of gastrointestinal adverse events were 50% higher in the colchicine group (OR 1.50, 95% CI 1.01-2.23; n = 12,214). In conclusion, colchicine is associated with a lower risk of acute myocardial infarction, stroke, and coronary revascularization. However, there is some increased risk of gastrointestinal adverse events with the use of colchicine.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Acidente Vascular Cerebral , Anti-Inflamatórios/efeitos adversos , Colchicina/efeitos adversos , Doença da Artéria Coronariana/tratamento farmacológico , Humanos , Infarto do Miocárdio/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle
17.
Ann Vasc Surg ; 87: 286-294, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35817384

RESUMO

BACKGROUND: Autogenous arteriovenous fistula (AVF) remains the standard of hemodialysis (HD) access; however, it cannot be reasonably obtained in all patients. For patients with contraindications to AVFs, prosthetic arteriovenous graft (AVG) remains an alternative. AVGs are plagued by high failure rates; however, there is a paucity of literature examining this. This study aims to examine a single-center review of outcomes of forearm loop AVGs in patients requiring HD access. METHODS: A single institution, retrospective chart review was completed from 2012 to 2019, including demographics, end-stage renal disease etiology, brachial vessel diameters, and comorbidities. Logistic regression and Cox proportional hazard models were evaluated. Outcomes were defined as primary patency (time elapsed from graft creation until it was utilized as the patient's primary access), primary-assisted patency (time from primary access to intervention to maintain patency), and functional patency (time from graft placement until graft failure). Additionally, multinomial regression models were used to evaluate associations with categorical number of required interventions. RESULTS: Ninety-eight patients [mean age 61.8 (13.9) years, 42.9% female] were identified as having brachial artery to brachial vein AVG creation during the study period, of which 75% achieved primary patency. Primary-assisted patency was 0.36 [standard error (SE) 0.07] at 6 months and 0.12 (SE 0.05) at 1 year. Functional patency was 0.75 (SE 0.07) at 6 months and 0.43 (SE 0.09) at 1 year. No association between preoperative vessel diameters and primary-assisted or functional patency was observed. Interestingly, there was a significant negative association between previous ipsilateral access and achievement of primary patency with a 60% decrease in odds of achieving primary patency in patients with previous ipsilateral access [odds ratio 0.4, 95% confidence interval (CI) 0.1-0.9, P = 0.03]. There was also noted to be a significant association between the presence of an ipsilateral catheter and increased risk of subsequent abandonment of the AVG (hazard ratio 2.6, 95% CI 1.1-5.8, P = 0.02). CONCLUSIONS: Prosthetic forearm loop AVGs remain hindered in their utility as they show high rates of graft failure within a year of creation. A significant patient-specific factor leading to this was not clearly demonstrated. As guidelines change regarding the nature of dialysis access for patients on HD, these results draw into question the utility of prosthetic forearm loop grafts in patients requiring long-term HD access.


Assuntos
Derivação Arteriovenosa Cirúrgica , Implante de Prótese Vascular , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Antebraço/irrigação sanguínea , Grau de Desobstrução Vascular , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Estudos Retrospectivos , Implante de Prótese Vascular/efeitos adversos , Fatores de Risco , Resultado do Tratamento , Fatores de Tempo , Diálise Renal/efeitos adversos
18.
J Arthroplasty ; 37(8S): S876-S880, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35093547

RESUMO

BACKGROUND: Hip precautions are traditionally employed after posterior total hip arthroplasty (THA). The primary purpose was to investigate the necessity of hip precautions after posterior approach THA. We hypothesized that eliminating precautions in patients that achieved appropriate intraoperative stability would not increase the dislocation rate. METHODS: Randomized controlled trial of 346 consecutive eligible patients undergoing primary THA with a mean follow-up of 2.3 years (range 11 months to 3.7 years). EXCLUSION CRITERIA: lumbar fusion, scoliosis, abductor insufficiency, inability to achieve intraoperative stability with combined 90° flexion and 45° internal rotation in 0° adduction. Fisher's exact test was used to compare dislocation rates between the hip precaution (HP) control group and no hip precaution (NP) study group. In addition, Mann-Whitney U test was used to compare differences in HOOS JR scores at 2, 6, 12 weeks between groups. RESULTS: The dislocation rate was not increased in the NP (0/172: 0%) group compared to the HP group 4/174 (2.29%) (P = .418). All dislocations occurred in the precautions group, two of which required revision. There were no differences in mean HOOS Jr. scores at any 2, 6, or 12 weeks (P > .05 at all timepoints) (secondary outcome). CONCLUSION: Eliminating hip precautions in patients undergoing posterior approach THA that achieve 90°/45°/0° intraoperative stability does not increase the rate of dislocation. In fact, every dislocation occurred in patients receiving hip precautions. Short-term patient-reported outcome measures were not affected by hip precautions. Surgeons may discontinue the use of hip precautions as the standard of care in patients achieving 90°/45°/0° stability.


Assuntos
Artroplastia de Quadril , Luxação do Quadril , Luxações Articulares , Luxação do Quadril/etiologia , Luxação do Quadril/prevenção & controle , Humanos , Estudos Prospectivos , Amplitude de Movimento Articular
19.
Exp Eye Res ; 206: 108556, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33794198

RESUMO

PURPOSE: The macaque retina is often used as a model for the human retina. However, there are only a handful of direct in vivo comparisons of the retinal physiology in humans and macaques. In the current study, ERG responses to luminance, L-cone isolating and M-cone isolating stimuli with sinusoidal, sawtooth and square wave temporal profiles were measured. The results were compared with those obtained from human observers. METHODS: The responses from five anesthetized adult macaques were measured. Full field stimuli were created. L- and M-cone isolating stimuli were based on the triple silent substitution technique. Sinusoidal stimuli had temporal frequencies between 4 and 56 Hz in 4 Hz steps. Sawtooth stimuli with rapid-on ramp-off and with rapid-off ramp-on excitation profiles had a frequency of 4 Hz. Square stimuli were presented at 2 Hz. RESULTS: Macaque and human ERGs in response to L- and M-cone isolating stimuli reflect L/M opponency and luminance activity. In responses to sine waves, cone opponency dominates at low temporal frequencies (4-12 Hz); luminance dominates at high temporal frequencies. The responses to sawtooth and square wave stimuli reflect a mixture of chromatic and luminance activity. L:M response ratios vary between individuals both in macaques and humans. Macaques show more complex responses, including greater second harmonic contributions than those in humans. CONCLUSIONS: Macaque and human ERGs share basic underlying mechanisms reflecting L/M opponency and luminance activity. There may be quantitative differences possibly reflecting differences in contributions of inner retinal mechanisms to the ERGs.


Assuntos
Eletrorretinografia/métodos , Células Fotorreceptoras Retinianas Cones/fisiologia , Animais , Macaca , Modelos Animais , Estimulação Luminosa/métodos
20.
Exp Eye Res ; 202: 108339, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127343

RESUMO

Guinea pigs are a common model of human ocular conditions; however, their visual function has not been fully characterized. The purpose of this study was to determine the contributions of retinal ganglion cells to structural and functional measures in guinea pigs. Healthy adult guinea pigs (n = 12) underwent unilateral optic nerve crush. Retinal structure was assessed with spectral domain optical coherence tomography (OCT), and thickness of the ganglion cell/nerve fiber layer (GC/NFL) was determined. Visual function was assessed with optomotor tracking of a drifting grating and light adapted electroretinograms (ERGs). From flash ERGs, a-wave, b-wave, oscillatory potentials (OPs), and photopic negative response (PhNR) were analyzed. From pattern ERGs, N1P1 and P1N2 were analyzed. Histological studies were done at various time points for ganglion cell quantification. Optomotor tracking was absent in optic nerve crush eyes following optic nerve crush. Significant thinning of the GC/NFL was evident four weeks following the crush. Flash ERGs revealed a significant reduction in the OP1 amplitude two weeks following crush (P < 0.01) and in the PhNR amplitude six weeks following crush (P < 0.01). There were no significant changes in a-wave, b-wave, or pattern ERG responses (P > 0.05 for all). In vivo OCT imaging showed progressive thinning of inner retinal layers. Ganglion cell density, quantified histologically, was significantly reduced by 75% in the optic nerve crush eye compared to the control eye at four weeks following crush. These findings indicate that retinal ganglion cells contribute to the PhNR and OP1 components of the full field flash ERG, but not significantly to the pattern ERG in guinea pigs. This study demonstrates that OCT imaging and full field flash ERGs are valuable in assessing retinal ganglion cell loss in vivo in guinea pigs and will help to further establish the guinea pig as a model of human ocular pathologies.


Assuntos
Fibras Nervosas/patologia , Traumatismos do Nervo Óptico/fisiopatologia , Retina/fisiopatologia , Células Ganglionares da Retina/patologia , Animais , Eletrorretinografia , Cobaias , Masculino , Compressão Nervosa , Estimulação Luminosa , Tomografia de Coerência Óptica
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