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1.
Clin Shoulder Elb ; 27(1): 3-10, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38303592

RESUMO

BACKGROUND: Gunshot-related fractures near the elbow are challenging, and available data to guide the practitioner are lacking. This report analyzes injury patterns and treatment strategies in a case series from a high-volume urban trauma center. METHODS: All periarticular gunshot fractures near the elbow treated at a level 1 trauma center from 2014 to 2018 were retrospectively reviewed. Fracture location, patient demographics, concomitant injuries, treatment modalities, and complications were analyzed. RESULTS: Twenty-four patients were identified. All patients received prophylactic antibiotics upon admission and underwent urgent surgical debridement. Open reduction and internal fixation (ORIF) was performed with initial debridement in 22 of 24 patients. Seven patients sustained distal humerus fractures, 10 patients sustained isolated proximal ulna or proximal radius fractures, and seven had combined fracture patterns. Eleven patients presented with nerve palsy, and two had transected nerves. Two patients had vascular injury requiring repair. One patient required a temporary elbow-spanning external fixator and underwent staged debridement followed by ORIF. One patient with a grade IIIC fracture developed a deep infection that precluded ORIF. One patient required revision ORIF due to fracture displacement. CONCLUSIONS: This investigation reports on management of ballistic fractures near the elbow at a busy urban level I trauma center. Our management centered on rapid debridement, early definitive fixation, and intravenous antibiotic administration. We report on associated neurovascular injury, bone loss, and other challenges in this patient population. Level of evidence: IV.

2.
ArXiv ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38351941

RESUMO

Contained within this volume are the scholarly contributions presented in both oral and poster formats at Fully3D 2023: The 17th International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine. This conference convened from July 16-21, 2023, at Stony Brook University in New York. For ease of reference, all papers are organized alphabetically according to the last names of the primary authors. Our heartfelt appreciation goes out to all participants who took the time to submit, present, and revise their work for inclusion in these proceedings. Collectively, we would also like to express our profound gratitude to our generous sponsors, detailed in subsequent pages, who have played an instrumental role in offering awards and facilitating the various conference activities. Additionally, our thanks extend to the diligent reporter who collated invaluable feedback from attendees, which can be found in the pages that follow. September 7, 2023 Fully3D 2023 Co-Chairs: Jerome Liang, Paul Vaska, and Chuan Huang.

3.
Eur Radiol Exp ; 8(1): 4, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172486

RESUMO

Recent advancements in diagnostic CT detector technology have made it possible to resolve anatomical features smaller than 20 LP/cm, referred to as ultra-high-resolution (UHR) CT. Subtle biological motions that did not affect standard-resolution (SR) CT may not be neglected in UHR. This study aimed to quantify the cardiac-induced motion of the pancreas and simulate its impact on the image quality of UHR-CT. We measured the displacement of the head of the pancreas in three healthy volunteers using Displacement Encoding with Stimulated Echoes (DENSE) MRI. The results were used to simulate SR- and UHR-CT acquisitions affected by pancreatic motion.We found pancreatic displacement in the 0.24-1.59 mm range during one cardiac cycle across the subjects. The greatest displacement was observed in the anterior-posterior direction. The time to peak displacement varied across subjects. Both SR and UHR images showed reduced image quality, as measured by radial modulation transfer function, due to cardiac-induced motion, but the motion artifacts caused more severe degradation in UHR acquisitions. Our investigation of cardiac-induced pancreatic displacement reveals its potential to degrade both standard and UHR-CT scans. To fully utilize the improvement in spatial resolution offered by UHR-CT, the effects of cardiac-induced motion in the abdomen need to be understood and corrected.Relevance statement Advancements in CT detector technology have enhanced CT scanner spatial resolution to approximately 100 µm. Consequently, previously ignored biological motions such as the cardiac-induced motion of the pancreas now demand attention to fully utilize this improved resolution.


Assuntos
Cavidade Abdominal , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Tomógrafos Computadorizados , Movimento (Física) , Pâncreas/diagnóstico por imagem
4.
J Nucl Med ; 64(12): 1980-1989, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918868

RESUMO

Tau PET has enabled the visualization of paired helical filaments of 3 or 4 C-terminal repeat tau in Alzheimer disease (AD), but its ability to detect aggregated tau in frontotemporal lobar degeneration (FTLD) spectrum disorders is uncertain. We investigated 2-(2-([18F]fluoro)pyridin-4-yl)-9H-pyrrolo[2,3-b:4,5c']dipyridine ([18F]PI-2620), a newer tracer with ex vivo evidence for binding to FTLD tau, in a convenience sample of patients with suspected FTLD and AD using a static acquisition protocol and parametric SUV ratio (SUVr) images. Methods: We analyzed [18F]PI-2620 PET data from 65 patients with clinical diagnoses associated with AD or FTLD neuropathology; most (60/65) also had amyloid-ß (Aß) PET. Scans were acquired 30-60 min after injection; SUVr maps (reference, inferior cerebellar cortex) were created for the full acquisition and for 10-min truncated sliding windows (30-40, 35-45,…50-60 min). Age- and sex-adjusted z score maps were computed for each patient, relative to 23 Aß-negative cognitively healthy controls (HC). Mean SUVr in the globus pallidus, substantia nigra, subthalamic nuclei, dentate nuclei, white matter, and temporal gray matter was extracted for the full and truncated windows. Results: Patients with suspected AD neuropathology (Aß-positive patients with mild cognitive impairment or AD dementia) showed high-intensity temporoparietal cortex-predominant [18F]PI-2620 binding. At the group level, patients with clinical diagnoses associated with FTLD (progressive supranuclear palsy with Richardson syndrome [PSP Richardson syndrome], corticobasal syndrome, and nonfluent-variant primary progressive aphasia) exhibited higher globus pallidus SUVr than did HCs; pallidal retention was highest in the PSP Richardson syndrome group, in whom SUVr was correlated with symptom severity (ρ = 0.53, P = 0.05). At the individual level, only half of PSP Richardson syndrome, corticobasal syndrome, and nonfluent-variant primary progressive aphasia patients had a pallidal SUVr above that of HCs. Temporal SUVr discriminated AD patients from HCs with high accuracy (area under the receiver operating characteristic curve, 0.94 [95% CI, 0.83-1.00]) for all time windows, whereas discrimination between patients with PSP Richardson syndrome and HCs using pallidal SUVr was fair regardless of time window (area under the receiver operating characteristic curve, 0.77 [95% CI, 0.61-0.92] at 30-40 min vs. 0.81 [95% CI, 0.66-0.96] at 50-60 min; P = 0.67). Conclusion: [18F]PI-2620 SUVr shows an intense and consistent signal in AD but lower-intensity, heterogeneous, and rapidly decreasing binding in patients with suspected FTLD. Further work is needed to delineate the substrate of [18F]PI-2620 binding and the usefulness of [18F]PI2620 SUVr quantification outside the AD continuum.


Assuntos
Doença de Alzheimer , Afasia Primária Progressiva , Degeneração Corticobasal , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Paralisia Supranuclear Progressiva , Humanos , Doença de Alzheimer/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Degeneração Lobar Frontotemporal/patologia , Peptídeos beta-Amiloides/metabolismo , Proteínas tau/metabolismo
5.
Int J Mol Sci ; 24(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37686064

RESUMO

In this report, we establish a straightforward method for estimating the equilibrium constant for the creatine kinase reaction (CK Keq″) over wide but physiologically and experimentally relevant ranges of pH, Mg2+ and temperature. Our empirical formula for CK Keq″ is based on experimental measurements. It can be used to estimate [ADP] when [ADP] is below the resolution of experimental measurements, a typical situation because [ADP] is on the order of micromolar concentrations in living cells and may be much lower in many in vitro experiments. Accurate prediction of [ADP] is essential for in vivo studies of cellular energetics and metabolism and for in vitro studies of ATP-dependent enzyme function under near-physiological conditions. With [ADP], we were able to obtain improved estimates of ΔGATP, necessitating the reinvestigation of previously reported ADP- and ΔGATP-dependent processes. Application to actomyosin force generation in muscle provides support for the hypothesis that, when [Pi] varies and pH is not altered, the maximum Ca2+-activated isometric force depends on ΔGATP in both living and permeabilized muscle preparations. Further analysis of the pH studies introduces a novel hypothesis around the role of submicromolar ADP in force generation.


Assuntos
Creatina Quinase , Músculos , Transdução de Sinais , Citoesqueleto de Actina , Trifosfato de Adenosina
6.
J Cardiovasc Comput Tomogr ; 17(5): 341-344, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37567802

RESUMO

BACKGROUND: Recent improvements in CT detector technology have led to smaller detector pixels resolving frequencies beyond 20 lp/cm and enabled ultra-high-resolution CT. Silicon-based photon-counting detector (PCD) CT is one such technology that promises improved spatial and spectral resolution. However, when the detector pixel sizes are reduced, the impact of cardiac motion on CT images becomes more pronounced. Here, we investigated the effects cardiac motion on the image quality of a clinical prototype Si-PCD scanner in a dynamic heart phantom. METHODS: A series of 3D-printed vessels were created to simulate coronary arteries with diameter in the 1-3.5 â€‹mm range. Four coronary stents were set inside the d â€‹= â€‹3.5 â€‹mm vessels and all vessels were filled with contrast agents and were placed inside a dynamic cardiac phantom. The phantom was scanned in motion (60 bpm) and at rest on a prototype clinical Si-PCD CT scanner in 8-bin spectral UHR mode. Virtual monoenergetic images (VMI) were generated at 70 â€‹keV and CT number accuracy and effective spatial resolution (blooming) of rest and motion VMIs were compared. RESULTS: Linear regression analysis of CT numbers showed excellent agreement (r â€‹> â€‹0.99) between rest and motion. We did not observe a significant difference (p â€‹> â€‹0.48) in estimating free lumen diameters. Differences in in-stent lumen diameter and stent strut thickness were non-significant with maximum mean difference of approximately 70 â€‹µm. CONCLUSION: We found no significant degradation in CT number accuracy or spatial resolution due to cardiac motion. The results demonstrate the potential of spectral UHR coronary CT angiography enabled by Si-PCD.


Assuntos
Angiografia por Tomografia Computadorizada , Silício , Humanos , Angiografia por Tomografia Computadorizada/métodos , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X/métodos , Angiografia Coronária/métodos , Imagens de Fantasmas
7.
J Cardiothorac Vasc Anesth ; 37(10): 1884-1893, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37481398

RESUMO

The EZ-Blocker (EZB) is a "Y-shaped," semirigid endobronchial blocker used for lung isolation and one-lung ventilation during thoracic surgery. Like many medical tools, initial efforts to use this endobronchial blocker may prove challenging for the uninitiated. However, some tips and tricks can be applied fairly rapidly to aid the clinician in properly placing the device, and, furthermore, may help the clinician get the most out of this innovative device. This article focuses on some of the technical aspects of its placement that the authors have developed over time. Additionally, other facets and potential pitfalls are discussed that relate to intraprocedural issues that may sometimes arise when using this device. The following aspects of the EZB as a lung-isolation device are discussed: standard positioning techniques, alternative positioning techniques, use in pediatric patients, approaches to achieving exceptional lung isolation, advanced uses, and limitations and potential issues. Although some information was taken from the authors' rather extensive experience with using this endobronchial blocker, some of the relevant literature are also reviewed, with the goal of being to improve the reader's knowledge of the device and improve the likelihood of its successful placement. The underlying design of the EZB remains unique among commercially available bronchial blockers in improving positional stability. The Y-shaped conformation, however, can lead to challenges when positioning the device in some patients. Therefore, some very practical tips and tricks are provided to assist the clinician in correctly positioning the device and other hints to improve the quality of lung isolation and surgical conditions.


Assuntos
Brônquios , Ventilação Monopulmonar , Humanos , Criança , Brônquios/cirurgia
8.
Int J Mol Sci ; 23(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35628144

RESUMO

Early life stress shapes the developing brain and increases risk for psychotic disorders. Yet, it is not fully understood how early life stress impacts brain regions in dopaminergic pathways whose dysfunction can contribute to psychosis. Therefore, we investigated gene expression following early life stress in adult brain regions containing dopamine neuron cell bodies (substantia nigra, ventral tegmental area (VTA)) and terminals (dorsal/ventral striatum). Sprague-Dawley rats (14F, 10M) were separated from their mothers from postnatal days (PND) 2-14 for 3 h/day to induce stress, while control rats (12F, 10M) were separated for 15 min/day over the same period. In adulthood (PND98), brain regions were dissected, RNA was isolated and five glucocorticoid signalling-related and six brain-derived neurotrophic factor (Bdnf) mRNAs were assayed by qPCR in four brain regions. In the VTA, levels of glucocorticoid signalling-related transcripts differed in maternally separated rodents compared to controls, with the Fkbp5 transcript significantly lower and Ptges3 transcript significantly higher in stressed offspring. In the VTA and substantia nigra, maternally separated rodents had significantly higher Bdnf IIA and III mRNA levels than controls. By contrast, in the ventral striatum, maternally separated rodents had significantly lower expression of Bdnf I, IIA, IIC, IV and VI transcripts. Sex differences in Nr3c1, Bag1 and Fkbp5 expression in the VTA and substantia nigra were also detected. Our results suggest that early life stress has long-lasting impacts on brain regions involved in dopamine neurotransmission, changing the trophic environment and potentially altering responsiveness to subsequent stressful events in a sex-specific pattern.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Estresse Psicológico , Animais , Feminino , Masculino , Ratos , Gânglios da Base/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Dopamina/metabolismo , Glucocorticoides , Ratos Sprague-Dawley , Roedores/metabolismo , Estresse Psicológico/metabolismo
9.
Paediatr Anaesth ; 32(8): 916-925, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35438816

RESUMO

BACKGROUND: The prevalence and risk factors for residual neuromuscular blockade in children remain poorly characterized. We hypothesize that specific patient and anesthetic risk factors may be associated with the administration of additional reversal in children following initial reversal of rocuronium with neostigmine. METHODS: Our electronic health record was queried for patients <18 years of age who received rocuronium and reversal with neostigmine from 2017 through 2020. Patients receiving other nondepolarizing neuromuscular blocking drugs were excluded. The outcome of interest was defined as the administration of additional neostigmine or sugammadex following primary reversal with neostigmine. Time between the last dose of rocuronium and initial dose of neostigmine, and the cumulative dose of rocuronium were dichotomized. These were combined with other covariates including age, weight, sex, racial group, procedure type, ASA physical status, >1 rocuronium dose administered during the procedure, initial neostigmine dose <0.05 mg kg-1 , use of train-of-four monitoring, duration of anesthesia, inpatient or outpatient, emergency case, neuromuscular disease, and extremes of weight, to assess possible associations with the primary outcome. RESULTS: During the study period, 101/6373 (1.58%) patients received rocuronium and additional reversal. Dichotomization of time between last dose of rocuronium and neostigmine yielded <28 min since the last dose of rocuronium and cumulative dose of rocuronium >0.45 mg kg-1 hr-1 . These were associated with the administration of additional reversal with an OR 1.52 (95% CI, 1.08-2.35) and OR 1.71 (95% CI, 1.10-2.67), respectively. Other risk factors included an initial neostigmine dose <0.05 mg kg-1 , OR 4.98 (95% CI, 2.84-6.49), and African American race, OR 1.78 (95% CI, 1.07-2.87). CONCLUSION: Risk factors associated with the administration of additional reversal included time <28 min from the last dose of rocuronium to initial dose of neostigmine, cumulative dose of rocuronium >0.45 mg kg-1 hr-1 , initial neostigmine dose <0.05 mg kg-1 , and African American race.


Assuntos
Anestésicos , Bloqueio Neuromuscular , Doenças Neuromusculares , Fármacos Neuromusculares não Despolarizantes , gama-Ciclodextrinas , Androstanóis , Estudos de Casos e Controles , Criança , Humanos , Neostigmina/farmacologia , Bloqueio Neuromuscular/efeitos adversos , Bloqueio Neuromuscular/métodos , Estudos Retrospectivos , Fatores de Risco , Rocurônio , gama-Ciclodextrinas/efeitos adversos
10.
Paediatr Anaesth ; 32(2): 346-353, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34767676

RESUMO

With the advent of thoracoscopic surgery, the benefits of lung isolation in children have been increasingly recognized. However, because of the small airway dimensions, equipment limitations in size and maneuverability, and limited respiratory reserve, one-lung ventilation in children remains challenging. This article highlights some of the most common error traps in the management of pediatric lung isolation and focuses on practical solutions for their management. The error traps discussed are as follows: (1) the failure to take into consideration relevant aspects of tracheobronchial anatomy when selecting the size of the lung isolation device, (2) failure to execute correct placement of the device chosen for lung isolation, (3) failure to maintain lung isolation related to surgical manipulation and isolation device movement, (4) failure to select appropriate ventilator strategies during one-lung ventilation, and (5) failure to appropriately manage and treat hypoxemia in the setting of one-lung ventilation.


Assuntos
Ventilação Monopulmonar , Criança , Humanos , Hipóxia/terapia , Intubação Intratraqueal/métodos , Pulmão , Ventilação Monopulmonar/métodos
11.
Paediatr Anaesth ; 32(2): 217-227, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34897894

RESUMO

Perioperative respiratory adverse events are the most common cause of critical events in children undergoing anesthesia and surgery. While many risk factors remain unmodifiable, there are numerous anesthetic management decisions which can impact the incidence and impact of these events, especially in at-risk children. Ongoing research continues to improve our understanding of both the influence of risk factors and the effect of specific interventions. This review discusses anesthesia risk factors and outlines strategies to reduce the rate and impact of perioperative respiratory adverse events with a chronologic based inquiry into anesthetic management decisions through the perioperative period from premedication to postoperative disposition.


Assuntos
Anestesia , Anestésicos , Anestesia/efeitos adversos , Anestésicos/efeitos adversos , Criança , Humanos , Período Perioperatório , Medição de Risco , Fatores de Risco
12.
Insects ; 12(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34442277

RESUMO

The fumigant pesticide methyl bromide (MB) was used for stored products, but it is now banned for most uses in many countries as an ozone-depleting substance. MB was the only pesticide used to manage the ham mite, Tyrophagus putrescentiae, which is the most significant pest of dry cured hams. Effective alternatives to MB are needed to develop integrated pest management (IPM) programs for this pest. This study evaluated plant essential oils and food-safe compounds as repellents to directly protect hams from infestation. Experiments to assess the repellency to orientation, oviposition, and population growth of mites on pieces of aged country hams were conducted. Test compounds at different concentrations were dissolved in respective solvents and compared to the solvent control. Results showed that C8910, a mixture of three short-chain fatty acids, and the sesquiterpene ketone nootkatone had repellency indices of (RI) of 85.6% and 82.3%, respectively, at a concentration of 0.1 mg/cm2, when applied to a Petri dish arena. DEET and icaridin were also tested but performed poorly with RIs below 70% even at 0.1 mg/cm2.The monoterpene alcohol geraniol had the highest RI of 96.3% at 0.04 mg/cm2. Ham pieces dipped in C8910 and nootkatone at 150 ppm each had RIs of 89.3% and 82.8%, respectively. In general, as the concentrations of test compounds increased, the numbers of eggs that were laid on these treated ham cubes decreased after the 48 h exposure time. Ham pieces dipped in different concentrations of test compounds and then inoculated with 20 adult mites showed a significant decrease in mite population growth compared to control pieces after 14 days. The results of these experiments suggest that some plant secondary metabolites and synthetic food-safe compounds could serve as potential alternatives for managing mites on hams.

13.
J Cereb Blood Flow Metab ; 41(12): 3302-3313, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34259071

RESUMO

The [18F]-JNJ-64326067-AAA ([18F]-JNJ-067) tau tracer was evaluated in healthy older controls (HCs), mild cognitive impairment (MCI), Alzheimer's disease (AD), and progressive supranuclear palsy (PSP) participants. Seventeen subjects (4 HCs, 5 MCIs, 5 ADs, and 3 PSPs) received a [11C]-PIB amyloid PET scan, and a tau [18F]-JNJ-067 PET scan 0-90 minutes post-injection. Only MCIs and ADs were amyloid positive. The simplified reference tissue model, Logan graphical analysis distribution volume ratio, and SUVR were evaluated for quantification. The [18F]-JNJ-067 tau signal relative to the reference region continued to increase to 90 min, indicating the tracer had not reached steady state. There was no significant difference in any bilateral ROIs for MCIs or PSPs relative to HCs; AD participants showed elevated tracer relative to controls in most cortical ROIs (P < 0.05). Only AD participants showed elevated retention in the entorhinal cortex. There was off-target signal in the putamen, pallidum, thalamus, midbrain, superior cerebellar gray, and white matter. [18F]-JNJ-067 significantly correlated (p < 0.05) with Mini-Mental State Exam in entorhinal cortex and temporal meta regions. There is clear binding of [18F]-JNJ-067 in AD participants. Lack of binding in HCs, MCIs and PSPs suggests [18F]-JNJ-067 may not bind to low levels of AD-related tau or 4 R tau.


Assuntos
Doença de Alzheimer , Encéfalo , Radioisótopos de Flúor/administração & dosagem , Isoquinolinas/administração & dosagem , Tomografia por Emissão de Pósitrons , Piridinas/administração & dosagem , Compostos Radiofarmacêuticos/administração & dosagem , Proteínas tau/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Feminino , Humanos , Masculino
14.
J Neurosci ; 41(17): 3917-3931, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33731446

RESUMO

Tau deposition begins in the medial temporal lobe (MTL) in aging and Alzheimer's disease (AD), and MTL neural dysfunction is commonly observed in these groups. However, the association between tau and MTL neural activity has not been fully characterized. We investigated the effects of tau on repetition suppression, the reduction of activity for repeated stimulus presentations compared to novel stimuli. We used task-based functional MRI (fMRI) to assess MTL subregional activity in 21 young adults (YA) and 45 cognitively normal human older adults (OA; total sample: 37 females, 29 males). AD pathology was measured with position emission tomography (PET), using 18F-Flortaucipir for tau and 11C-Pittsburgh compound B (PiB) for amyloid-ß (Aß). The MTL was segmented into six subregions using high-resolution structural images. We compared the effects of low tau pathology, restricted to entorhinal cortex and hippocampus (Tau- OA), to high tau pathology, also occurring in temporal and limbic regions (Tau+ OA). Low levels of tau (Tau- OA vs YA) were associated with reduced repetition suppression activity specifically in anterolateral entorhinal cortex (alEC) and hippocampus, the first regions to accumulate tau. High tau pathology (Tau+ vs Tau- OA) was associated with widespread reductions in repetition suppression across MTL. Further analyses indicated that reduced repetition suppression was driven by hyperactivity to repeated stimuli, rather than decreased activity to novel stimuli. Increased activation was associated with entorhinal tau, but not Aß. These findings reveal a link between tau deposition and neural dysfunction in MTL, in which tau-related hyperactivity prevents deactivation to repeated stimuli, leading to reduced repetition suppression.SIGNIFICANCE STATEMENT Abnormal neural activity occurs in the medial temporal lobe (MTL) in aging and Alzheimer's disease (AD). Because tau pathology first deposits in the MTL in aging, this altered activity may be due to local tau pathology, and distinct MTL subregions may be differentially vulnerable. We demonstrate that in older adults (OAs) with low tau pathology, there are focal alterations in activity in MTL subregions that first develop tau pathology, while OAs with high tau pathology have aberrant activity throughout MTL. Tau was associated with hyperactivity to repeated stimulus presentations, leading to reduced repetition suppression, the discrimination between novel and repeated stimuli. Our data suggest that tau deposition is related to abnormal activity in MTL before the onset of cognitive decline.


Assuntos
Envelhecimento/fisiologia , Lobo Temporal/fisiologia , Proteínas tau/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Córtex Entorrinal/diagnóstico por imagem , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Priming de Repetição , Tauopatias/diagnóstico por imagem , Tauopatias/psicologia , Lobo Temporal/metabolismo , Adulto Jovem , Proteínas tau/metabolismo
15.
J Bone Miner Res ; 36(2): 357-368, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33053220

RESUMO

Legg-Calvé-Perthes disease (LCPD) is a juvenile form of ischemic femoral head osteonecrosis, which produces chronic hip synovitis, permanent femoral head deformity, and premature osteoarthritis. Currently, there is no medical therapy for LCPD. Interleukin-6 (IL-6) is significantly elevated in the synovial fluid of patients with LCPD. We hypothesize that IL-6 elevation promotes chronic hip synovitis and impairs bone healing after ischemic osteonecrosis. We set out to test if anti-IL-6 therapy using tocilizumab can decrease hip synovitis and improve bone healing in the piglet model of LCPD. Fourteen piglets were surgically induced with ischemic osteonecrosis and assigned to two groups: the no treatment group (n = 7) and the tocilizumab group (15 to 20 mg/kg, biweekly intravenous injection, n = 7). All animals were euthanized 8 weeks after the induction of osteonecrosis. Hip synovium and femoral heads were assessed for hip synovitis and bone healing using histology, micro-CT, and histomorphometry. The mean hip synovitis score and the number of synovial macrophages and vessels were significantly lower in the tocilizumab group compared with the no treatment group (p < .0001, p = .01, and p < .01, respectively). Micro-CT analysis of the femoral heads showed a significantly higher bone volume in the tocilizumab group compared with the no treatment group (p = .02). The histologic assessment revealed a significantly lower number of osteoclasts per bone surface (p < .001) in the tocilizumab group compared with the no treatment group. Moreover, fluorochrome labeling showed a significantly higher percent of mineralizing bone surface (p < .01), bone formation rate per bone surface (p < .01), and mineral apposition rate (p = .04) in the tocilizumab group. Taken together, tocilizumab therapy decreased hip synovitis and osteoclastic bone resorption and increased new bone formation after ischemic osteonecrosis. This study provides preclinical evidence that tocilizumab decreases synovitis and improves bone healing in a large animal model of LCPD. © 2020 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Reabsorção Óssea , Doença de Legg-Calve-Perthes , Osteonecrose , Sinovite , Animais , Reabsorção Óssea/tratamento farmacológico , Cabeça do Fêmur/diagnóstico por imagem , Humanos , Osteogênese , Suínos
16.
Korean J Anesthesiol ; 74(3): 218-225, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33198431

RESUMO

BACKGROUND: Supraglottic airway (SGA) devices including the air-Q® are being used with increasing frequency for anesthesia in infants and younger pediatric patients. To date, there is minimal research documenting the potentially significant airway deadspace these devices may contribute to the ventilation circuit when compared to an endotracheal tube (ETT). The aim of this study was to evaluate the airway apparatus deadspace associated with an air-Q® versus an ETT in young children. METHODS: In a prospective cohort study, 59 patients between 3 months and 6 years of age, weighing between 5 and 20 kg, scheduled for outpatient urologic or general surgery procedures were recruited. An air-Q® or ETT was inserted at the discretion of the attending anesthesiologist, and tidal volume, positive end expiratory pressure, respiratory rate, and end-tidal CO2 were controlled according to protocol. Airway deadspace was recorded using volumetric capnography every 2 min for 10 min. RESULTS: Groups were similar in demographics. There was a significant difference in weight-adjusted deadspace volume between the air-Q® and ETT groups, 4.1 ± 0.8 ml/kg versus 3.0 ± 0.7 ml/kg, respectively (P < 0.001). Weight-adjusted deadspace volume (ml/kg) increased significantly with decreasing weight for both the air-Q® and ETT groups. CONCLUSIONS: In healthy children undergoing positive pressure ventilation for elective surgery, the air-Q® SGA introduces significantly greater airway deadspace than an ETT. Additionally, airway deadspace, and minute ventilation required to maintain normocarbia, appear to increase with decreasing patient weight irrespective of whether a SGA or ETT is used.


Assuntos
Capnografia , Máscaras Laríngeas , Criança , Pré-Escolar , Humanos , Lactente , Intubação Intratraqueal/efeitos adversos , Estudos Prospectivos , Respiração Artificial
17.
Front Immunol ; 11: 1869, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973771

RESUMO

Immune cells rely on cell-cell communication to specify and fine-tune their responses. They express an extensive network of cell communication modes, including a vast repertoire of cell surface and transmembrane receptors and ligands, membrane vesicles, junctions, ligand and voltage-gated ion channels, and transporters. During a crosstalk between the nervous system and the immune system these modes of cellular communication and the downstream signal transduction events are influenced by neurotransmitters present in the local tissue environments in an autocrine or paracrine fashion. Neurotransmitters thus influence innate and adaptive immune responses. In addition, immune cells send signals to the brain through cytokines, and are present in the brain to influence neural responses. Altered communication between the nervous and immune systems is emerging as a common feature in neurodegenerative and immunopathological diseases. Here, we present the mechanistic frameworks of immunostimulatory and immunosuppressive effects critical neurotransmitters - dopamine (3,4-dihydroxyphenethylamine), serotonin (5-hydroxytryptamine), substance P (trifluoroacetate salt powder), and L-glutamate - exert on lymphocytes and non-lymphoid immune cells. Furthermore, we discuss the possible roles neurotransmitter-driven neuroimmune networks play in the pathogenesis of neurodegenerative disorders, autoimmune diseases, cancer, and outline potential clinical implications of balancing neuroimmune crosstalk by therapeutic modulation.


Assuntos
Neuroimunomodulação/imunologia , Neurotransmissores/imunologia , Animais , Humanos
18.
J Atr Fibrillation ; 13(2): 2326, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34950295

RESUMO

BACKGROUND: Hypertension (HTN) and atrial fibrillation (AF) commonly co-exist. An improvement in control of HTN in a subset of patients undergoing AF ablation was previously demonstrated by our group. In the present study, we aimed to assess whether left atrial (LA) size based on transthoracic echocardiography may predict the patients who demonstratebetter HTN improvement after ganglionated plexus ablation (GPA) in addition to pulmonary vein isolation (PVI). METHODS: This was a retrospective chart review of patients with AF and HTN who underwent GPA+PVI. Patients were divided into 2 groupsbased on LA size: Patients with normal LA size and patients with LA enlargement. Systolic blood pressure (SBP) levelswere compared at baseline, and 3, 6, and 12 months post-ablation. The primary endpoints of the study weremean systolic blood pressure change compared between groups from baseline to 12-months, as well as the absolute difference in systolic blood pressure at 12 months follow-up.Medical therapy for HTN was also assessed before the procedure, and at 12 months post-procedure. RESULTS: 53 patients (37 with LA enlargement, 16 with normal LA size) met inclusion criteria. At 12 months follow-up, SBP was 136.46 ± 22.38 mmHg in patients with LA enlargementand 118.25 ± 9.81 mmHg in patients with normal LA size (estimated difference of 19.04 ± 6.98 mmHg, p = 0.01). Patients with normal LA size were on significantly fewer anti-hypertensive agents at 12 months (2.33 ± 1.49 vs. 1.44 ± 1.21, p < 0.05). CONCLUSIONS: In patients undergoing PVI+GP ablation, normal LA size may predict HTN improvement at 12 months post-procedure. Normal LA size may identify hypertensive AF patients for whom autonomic modulation could be an effective therapy.

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