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1.
Nature ; 590(7844): 111-114, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33328635

RESUMO

Single neocortical neurons are driven by populations of excitatory inputs, which form the basis of neuronal selectivity to features of sensory input. Excitatory connections are thought to mature during development through activity-dependent Hebbian plasticity1, whereby similarity between presynaptic and postsynaptic activity selectively strengthens some synapses and weakens others2. Evidence in support of this process includes measurements of synaptic ultrastructure and in vitro and in vivo physiology and imaging studies3-8. These corroborating lines of evidence lead to the prediction that a small number of strong synaptic inputs drive neuronal selectivity, whereas weak synaptic inputs are less correlated with the somatic output and modulate activity overall6,7. Supporting evidence from cortical circuits, however, has been limited to measurements of neighbouring, connected cell pairs, raising the question of whether this prediction holds for a broad range of synapses converging onto cortical neurons. Here we measure the strengths of functionally characterized excitatory inputs contacting single pyramidal neurons in ferret primary visual cortex (V1) by combining in vivo two-photon synaptic imaging and post hoc electron microscopy. Using electron microscopy reconstruction of individual synapses as a metric of strength, we find no evidence that strong synapses have a predominant role in the selectivity of cortical neuron responses to visual stimuli. Instead, selectivity appears to arise from the total number of synapses activated by different stimuli. Moreover, spatial clustering of co-active inputs appears to be reserved for weaker synapses, enhancing the contribution of weak synapses to somatic responses. Our results challenge the role of Hebbian mechanisms in shaping neuronal selectivity in cortical circuits, and suggest that selectivity reflects the co-activation of large populations of presynaptic neurons with similar properties and a mixture of strengths.


Assuntos
Vias Neurais , Células Piramidais/metabolismo , Sinapses/metabolismo , Córtex Visual/citologia , Córtex Visual/fisiologia , Animais , Feminino , Furões , Microscopia Eletrônica de Varredura , Modelos Neurológicos , Estimulação Luminosa , Células Piramidais/ultraestrutura , Sinapses/ultraestrutura
2.
Glia ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856149

RESUMO

Most excitatory synapses in the mammalian brain are contacted or ensheathed by astrocyte processes, forming tripartite synapses. Astrocytes are thought to be critical regulators of the structural and functional dynamics of synapses. While the degree of synaptic coverage by astrocytes is known to vary across brain regions and animal species, the reason for and implications of this variability remains unknown. Further, how astrocyte coverage of synapses relates to in vivo functional properties of individual synapses has not been investigated. Here, we characterized astrocyte coverage of synapses of pyramidal neurons in the ferret visual cortex and, using correlative light and electron microscopy, examined their relationship to synaptic strength and sensory-evoked Ca2+ activity. Nearly, all synapses were contacted by astrocytes, and most were contacted along the axon-spine interface. Structurally, we found that the degree of synaptic astrocyte coverage directly scaled with synapse size and postsynaptic density complexity. Functionally, we found that the amount of astrocyte coverage scaled with how selectively a synapse responds to a particular visual stimulus and, at least for the largest synapses, scaled with the reliability of visual stimuli to evoke postsynaptic Ca2+ events. Our study shows astrocyte coverage is highly correlated with structural metrics of synaptic strength of excitatory synapses in the visual cortex and demonstrates a previously unknown relationship between astrocyte coverage and reliable sensory activation.

3.
Am J Public Health ; 114(S5): S392-S395, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38776503

RESUMO

The Black church has long been seen as a crucial partner in addressing public health issues. This paper describes the development, implementation, and evaluation of a community-engaged church intervention addressing COVID-19 vaccine hesitancy in underserved Black communities in Jefferson County, Alabama. We partnered with churches to implement and evaluate the intervention between March and June of 2022 and found that our church partners were capable of significant messaging reach, particularly through electronic means. (Am J Public Health. 2024;114(S5):S392-S395. https://doi.org/10.2105/AJPH.2024.307683).


Assuntos
Negro ou Afro-Americano , Vacinas contra COVID-19 , COVID-19 , Hesitação Vacinal , Humanos , Vacinas contra COVID-19/administração & dosagem , Alabama , Hesitação Vacinal/psicologia , COVID-19/prevenção & controle , Negro ou Afro-Americano/psicologia , Confiança , SARS-CoV-2
4.
Eur Radiol ; 34(2): 810-822, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37606663

RESUMO

OBJECTIVES: Non-contrast computed tomography of the brain (NCCTB) is commonly used to detect intracranial pathology but is subject to interpretation errors. Machine learning can augment clinical decision-making and improve NCCTB scan interpretation. This retrospective detection accuracy study assessed the performance of radiologists assisted by a deep learning model and compared the standalone performance of the model with that of unassisted radiologists. METHODS: A deep learning model was trained on 212,484 NCCTB scans drawn from a private radiology group in Australia. Scans from inpatient, outpatient, and emergency settings were included. Scan inclusion criteria were age ≥ 18 years and series slice thickness ≤ 1.5 mm. Thirty-two radiologists reviewed 2848 scans with and without the assistance of the deep learning system and rated their confidence in the presence of each finding using a 7-point scale. Differences in AUC and Matthews correlation coefficient (MCC) were calculated using a ground-truth gold standard. RESULTS: The model demonstrated an average area under the receiver operating characteristic curve (AUC) of 0.93 across 144 NCCTB findings and significantly improved radiologist interpretation performance. Assisted and unassisted radiologists demonstrated an average AUC of 0.79 and 0.73 across 22 grouped parent findings and 0.72 and 0.68 across 189 child findings, respectively. When assisted by the model, radiologist AUC was significantly improved for 91 findings (158 findings were non-inferior), and reading time was significantly reduced. CONCLUSIONS: The assistance of a comprehensive deep learning model significantly improved radiologist detection accuracy across a wide range of clinical findings and demonstrated the potential to improve NCCTB interpretation. CLINICAL RELEVANCE STATEMENT: This study evaluated a comprehensive CT brain deep learning model, which performed strongly, improved the performance of radiologists, and reduced interpretation time. The model may reduce errors, improve efficiency, facilitate triage, and better enable the delivery of timely patient care. KEY POINTS: • This study demonstrated that the use of a comprehensive deep learning system assisted radiologists in the detection of a wide range of abnormalities on non-contrast brain computed tomography scans. • The deep learning model demonstrated an average area under the receiver operating characteristic curve of 0.93 across 144 findings and significantly improved radiologist interpretation performance. • The assistance of the comprehensive deep learning model significantly reduced the time required for radiologists to interpret computed tomography scans of the brain.


Assuntos
Aprendizado Profundo , Adolescente , Humanos , Radiografia , Radiologistas , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto
6.
Microsc Microanal ; 27(1): 156-169, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33303051

RESUMO

Brain circuits are highly interconnected three-dimensional structures fabricated from components ranging vastly in size; from cell bodies to individual synapses. While neuronal activity can be visualized with advanced light microscopy (LM) techniques, the resolution of electron microscopy (EM) is critical for identifying synaptic connections between neurons. Here, we combine these two techniques, affording the advantage of each and allowing for measurements to be made of the same neural features across imaging platforms. We established an EM-label-free workflow utilizing inherent structural features to correlate in vivo two-photon LM and volumetric scanning EM (SEM) in the ferret visual cortex. By optimizing the volume SEM sample preparation protocol, imaging with the OnPoint detector, and utilizing the focal charge compensation device during serial block-face imaging, we achieved sufficient resolution and signal-to-noise ratio to analyze synaptic ultrastructure for hundreds of synapses within sample volumes. Our novel workflow provides a reliable method for quantitatively characterizing synaptic ultrastructure in functionally imaged neurons, providing new insights into neuronal circuit organization.


Assuntos
Imageamento Tridimensional , Neurônios , Microscopia Eletrônica de Varredura , Neurônios/ultraestrutura
7.
Ann Plast Surg ; 85(6): 661-667, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32118638

RESUMO

BACKGROUND: Surgical procedures interfering with the draining nodes in the inguinal region carry the intrinsic risk of lymphatic complications. Lesions of the inguinal lymphatic network can lead to lymphocele or lymphocutaneous fistulas and can eventually be associated to limb lymphedema with consequent high morbidity. OBJECTIVES: This article describes a new surgical algorithm based on wound properties to properly address lymphatic complications of the inguinal area. Based on our experience, surgical solutions ranged from selective lymphatic vessel ligation to microsurgical lymphatic fistula treatment and free tissue transfer. METHODS: Fourteen consecutive patients underwent surgery in our department following failed attempts to address persistent lymphatic leaks. Patient characteristics such as smoking, previous surgeries, comorbidities, and wound properties were considered. Identification of the leak was performed using blue patent dye and indocyanine green fluorescence. Surgical reconstruction occurred, according to our algorithm. RESULTS: Lymphatic leaks were visualized in 11 of 14 patients. Direct closure of the wound after leak ligation could be performed in 4 of 14 patients. Multilymphatic into vein anastomosis was performed in 3 of 14 patients, and the remaining patients benefited from flap surgery based on the wound defects. All 14 patients had successful outcomes (100%) with early drain removal (average, 6 [SD, 6] days) and definitive wound healing 2 weeks postoperatively. After a mean follow-up of 12 (SD, 2.9) months, no clinical infection, lymphatic complication, or wound breakdown occurred. One patient had a partial recurrence that did not require surgical intervention. CONCLUSIONS: A stepwise approach, combining lymphatic surgery principles and plastic surgery flap techniques, can lead to an effective treatment algorithm where surgical options are wound tailored to guarantee the best functional outcomes.


Assuntos
Vasos Linfáticos , Cirurgia Plástica , Algoritmos , Humanos , Vasos Linfáticos/cirurgia , Recidiva Local de Neoplasia , Coxa da Perna
8.
Int J Clin Pract ; : e13216, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29920884

RESUMO

OBJECTIVE: The aim of this study was .to systematically review the published literature of observational studies evaluating the safety and effectiveness of hospital in the home (HITH) and outpatient parenteral antimicrobial therapy (OPAT) in the general population, older people and children. STUDY DESIGN: The review included retrospective studies and prospective studies performed on HITH and OPAT within different age groups. Only the studies that analysed the safety and effectiveness of HITH and OPAT were included for review. DATA SOURCES: A literature search of electronic databases CINAHL, Web of Science, PubMed and SCOPUS from 1997 to 2016 was performed. DATA SYNTHESIS: Forty-four studies met the inclusion criteria. Five studies were undertaken on HITH within the general population, 26 studies were undertaken on OPAT within the general population, 8 studies were on HITH and OPAT for older people and 5 studies were on OPAT with children. More than 88% of the studies reported a cure or treatment success rate of greater than 80%. Adverse events with drugs ranged from 0% to 30.2%; adverse events with vascular access devices ranged from 0% to 29%; readmission rate varied from 1% to 26%; mortality varied from 0% to 27.5%. CONCLUSIONS: This review quantifies the rates of success and harm in real world practice, and demonstrates that while most patients experience treatment success, adverse events may be high in some groups. However, the methodologies used to measure these parameters were inconsistent and some demographic groups had only a small number of studies.

9.
Ann Plast Surg ; 78(2): 184-190, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27404468

RESUMO

BACKGROUND: In lymphedema, excess adipose tissue occurs with progression of the disease because of chronic lymph stasis, impeding lymphatic flow. Recently, liposuction has been used as a less-invasive procedure to remove this excess tissue. Given the existing poor lymph drainage in patients with lymphatic diseases, extra caution should be taken to avoid damaging lymphatic vessels during liposuction. We developed a new technique (Fibro-Lipo-Lymph-Aspiration with a Lymph Vessel Sparing Procedure [FLLA-LVSP]) to improve chronic swelling in patients with advanced lymphedema. The FLLA-LSVP highlights the superficial lymphatic pathways in the treated limb. This visibility allows surgeons to avoid these pathways, while removing the maximum amount of excess tissue. METHOD: One hundred forty-six patients with primary or secondary lymphedema that had already been treated by lymphatic microsurgery, in Genoa, Italy, were included in this retrospective study. All patients had residual fibrotic/adipose tissue, resistant to conservative treatments. Indocyanine green fluorescent dye and Blue Patent Violet dye were injected laterally/medially to the main superficial veins at the wrist/ankle of the limb to be treated. Using a photodynamic camera, the superficial lymphatic network was made visible and sketched onto the skin in indelible ink. After the microlymphography, the excess adipose tissue was carefully aspirated. Preoperative and postoperative excess limb volume was calculated using circumferential measurements and the formula of a frustum. RESULTS: For the upper limb, 0.80 L, on average, and 2.42 L for the lower limb were removed with the FLLA-LVSP. For the upper limb, there was an average presurgery excess volume of 20.19%, which reduced to 2.68% after the FLLA-LVSP (Z score = -6.90, P < 0.001). Similarly, for the lower limb, there was an average presurgery excess limb volume of 21.24% and a reduction to 2.64% postoperatively (Z score = -3.57, P < 0.01). Immediate postoperative microlymphography and Blue Patent Violet test confirmed no lymphatic complications. No episodes of postoperative infection occurred. CONCLUSIONS: The FLLA-LVSP is efficient. An entire leg can be completed within 90 minutes. Recovery time is short, and cosmetic results are immediate. More importantly, the removal of excess tissue is completed without further damage to lymphatic vessels. When used after microsurgery, FLLA-LVSP offers the possibility of removing almost all obstacles to lymphatic flow.


Assuntos
Lipectomia/métodos , Vasos Linfáticos/cirurgia , Linfedema/cirurgia , Microcirurgia , Veias/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Feminino , Seguimentos , Humanos , Masculino , Microcirurgia/métodos , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
10.
Ann Plast Surg ; 79(3): 298-303, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28570444

RESUMO

BACKGROUND: Advanced microsurgical techniques have emerged as a promising approach for the treatment of lymphedema, but achieving international standards is limited by a scarcity of adequate training models. The purpose of this report is to describe our in vivo porcine training model for microsurgery. STUDY DESIGN: Five female common-breed pigs (Sus scrofa domesticus) weighing 20 to 28 kg were placed under general anesthesia, and blue patent violet dye was injected to highlight lymphatic structures and prepare the pigs for anatomical exploration and microsurgery. The number and type of patent anastomoses achieved and lymph node flaps created and any anatomical differences between porcine and human vessels were noted, in light of evaluating the use of pigs as a training model for microsurgery in living tissue. RESULTS: Multiple lymphatic-venous anastomoses were created at the site of a single incision made at the subinguinal region, running medial and parallel to the saphenous vessels. Ten multiple lymphatic-venous anastomoses were created in total, and all were demonstrated to be patent. Four lymph node flaps were prepared for lymph node transfer. The superficial lymphatic collector system in the caudal limb of the pig was identified and described with particular reference to the superficial, medial (dominant), and lateral branches along the saphenous vein and its accessory. CONCLUSIONS: The authors present a safe and adaptable in vivo experimental microsurgical porcine model that provides the opportunity to practice several advanced lymphatic microsurgical techniques in the same animal. The ideal lymph node transfer training model can be developed from this anatomical detail, giving the opportunity to use it for artery-to-artery anastomoses, vein-to-vein anastomoses, and lymphatic-to-lymphatic anastomoses.


Assuntos
Anastomose Cirúrgica/métodos , Linfonodos/cirurgia , Vasos Linfáticos/cirurgia , Microcirurgia/métodos , Animais , Humanos , Modelos Animais , Corantes de Rosanilina/administração & dosagem , Suínos
11.
J Reconstr Microsurg ; 32(1): 42-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26029991

RESUMO

BACKGROUND: The authors' vast surgical experience in the treatment of primary and secondary peripheral lymphedemas using microsurgical procedures at the Centre of Lymphatic Surgery and Microsurgery of the University of Genoa, Italy, is reported. The objective is to describe the techniques and the long-lasting clinical outcomes based on 40 years' experience and research, with particular reference to advanced derivative and reconstructive lymphatic microsurgery at a single site. METHODS: More than 2,600 patients affected by upper and/or lower limb lymphedema, between 1973 and 2013, underwent lymphatic microsurgery. Derivative multiple lymphatic-venous anastomoses (MLVA) or lymphatic pathway reconstruction using interpositioned vein-grafted shunts multiple lymphatic venous lymphatic anastomoses (MLVLA) were performed at a single site, either the axillary or inguinal-crural region. Patients were followed up for a minimum of 5 years to over 20 years. Clinical outcomes included excess limb volume (ELV), frequency of dermatolymphangioadenitis (DLA) attacks, and use of conservative therapies. RESULTS: Compared with preoperative conditions, patients obtained significant reductions in ELV of over 84%, with an average follow-up of 10 years or more. Over 86% of patients with earlier stages of disease (stage IB or IIA) progressively stopped using conservative therapies and 42% of patients with later stages (stages IIB and III) decreased the frequency of physical therapies. DLA attacks considerably reduced by over 91%. CONCLUSION: MLVA or MLVLA techniques when performed at a single site produce excellent outcomes in the treatment of both primary and secondary lymphedemas, giving the possibility of a complete restoration of lymphatic flow in early stages of disease when tissue changes are minimal.


Assuntos
Vasos Linfáticos/cirurgia , Linfedema/cirurgia , Microcirurgia/métodos , Veias/cirurgia , Anastomose Cirúrgica , Feminino , Humanos , Extremidade Inferior/cirurgia , Linfocintigrafia , Masculino , Complicações Pós-Operatórias , Resultado do Tratamento , Extremidade Superior/cirurgia
12.
Healthcare (Basel) ; 12(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38470689

RESUMO

Low- (or mild-) gain hearing aids (LGHAs) are increasingly considered for individuals with normal peripheral hearing but significant self-reported hearing difficulties (SHDs). This study assesses the benefits of LGHAs as a management option for individuals with normal hearing thresholds (NHTs) and SHDs, comparing LGHA use and benefit to individuals with non-significant hearing difficulties (NHDs) and those with peripheral hearing loss. Questionnaires addressing hearing aid usage, benefit, hearing difficulties, and tinnitus were administered to 186 individuals who self-identified as hearing aid users in a sample of 6652 service members who were receiving their annual hearing tests. Participants were divided into SHD and NHD groups based on the normative cutoff of the Tinnitus and Hearing Survey-Hearing Subscale (THS-H), and into hearing impairment (HI) and NHT based on their audiometric air-conduction thresholds. Individuals with SHDs and NHTs reported higher LGHA usage and benefit than individuals with NHDs and NHTs. Comparable use and benefit were noted between groups with SHDs regardless of peripheral hearing loss status. The findings support LGHAs as a suitable management option for individuals with NHTs and SHDs, as indicated by hearing aid use and benefit. Quantifying the level of perceived auditory processing deficits (i.e., SHDs), notably with the THS-H, enhances sensitivity in identifying those who may benefit the most from this treatment option.

13.
bioRxiv ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37502969

RESUMO

Postsynaptic mitochondria are critical to the development, plasticity, and maintenance of synaptic inputs. However, their relationship to synaptic structure and functional activity is unknown. We examined a correlative dataset from ferret visual cortex with in vivo two-photon calcium imaging of dendritic spines during visual stimulation and electron microscopy (EM) reconstructions of spine ultrastructure, investigating mitochondrial abundance near functionally- and structurally-characterized spines. Surprisingly, we found no correlation to structural measures of synaptic strength. Instead, we found that mitochondria are positioned near spines with orientation preferences that are dissimilar to the somatic preference. Additionally, we found that mitochondria are positioned near groups of spines with heterogeneous orientation preferences. For a subset of spines with mitochondrion in the head or neck, synapses were larger and exhibited greater selectivity to visual stimuli than those without a mitochondrion. Our data suggest mitochondria are not necessarily positioned to support the energy needs of strong spines, but rather support the structurally and functionally diverse inputs innervating the basal dendrites of cortical neurons.

14.
Elife ; 122023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059805

RESUMO

Postsynaptic mitochondria are critical for the development, plasticity, and maintenance of synaptic inputs. However, their relationship to synaptic structure and functional activity is unknown. We examined a correlative dataset from ferret visual cortex with in vivo two-photon calcium imaging of dendritic spines during visual stimulation and electron microscopy reconstructions of spine ultrastructure, investigating mitochondrial abundance near functionally and structurally characterized spines. Surprisingly, we found no correlation to structural measures of synaptic strength. Instead, we found that mitochondria are positioned near spines with orientation preferences that are dissimilar to the somatic preference. Additionally, we found that mitochondria are positioned near groups of spines with heterogeneous orientation preferences. For a subset of spines with a mitochondrion in the head or neck, synapses were larger and exhibited greater selectivity to visual stimuli than those without a mitochondrion. Our data suggest mitochondria are not necessarily positioned to support the energy needs of strong spines, but rather support the structurally and functionally diverse inputs innervating the basal dendrites of cortical neurons.


Assuntos
Espinhas Dendríticas , Furões , Animais , Espinhas Dendríticas/fisiologia , Dendritos/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Mitocôndrias
15.
bioRxiv ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38106030

RESUMO

Most excitatory synapses in the mammalian brain are contacted by astrocytes, forming the tripartite synapse. This interface is thought to be critical for glutamate turnover and structural or functional dynamics of synapses. While the degree of synaptic contact of astrocytes is known to vary across brain regions and animal species, the implications of this variability remain unknown. Furthermore, precisely how astrocyte coverage of synapses relates to in vivo functional properties of individual dendritic spines has yet to be investigated. Here, we characterized perisynaptic astrocyte processes (PAPs) contacting synapses of pyramidal neurons of the ferret visual cortex and, using correlative light and electron microscopy, examined their relationship to synaptic strength and to sensory-evoked Ca2+ activity. Nearly all synapses were contacted by PAPs, and most were contacted along the axon-spine interface (ASI). Structurally, we found that the degree of PAP coverage scaled with synapse size and complexity. Functionally, we found that PAP coverage scaled with the selectivity of Ca2+ responses of individual synapses to visual stimuli and, at least for the largest synapses, scaled with the reliability of visual stimuli to evoke postsynaptic Ca2+ events. Our study shows astrocyte coverage is highly correlated with structural properties of excitatory synapses in the visual cortex and implicates astrocytes as a contributor to reliable sensory activation.

16.
Am J Health Promot ; 37(5): 720-721, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36630288

RESUMO

The purpose of this submission to respond to a Letter to the Editor recently submitted regarding our manuscript, "Exploring COVID-19 Vaccine Hesitancy among Stakeholders in African American and Latinx Communities in the Deep South through the Lens of the Health Belief Model" published in the American Journal of Health Promotion in February, 2022. The manuscript reported on a study that had as its purpose to qualitatively explore perceptions related to COVID-19 vaccination intention among African American and Latinx participants and suggest potential intervention strategies.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Negro ou Afro-Americano , COVID-19/prevenção & controle , Modelo de Crenças de Saúde , Vacinação , Hispânico ou Latino
17.
Neuron ; 110(9): 1573-1584.e4, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35123654

RESUMO

In visual cortex, signals from the two eyes merge to form a coherent binocular representation. Here we investigate the synaptic interactions underlying the binocular representation of stimulus orientation in ferret visual cortex with in vivo calcium imaging of layer 2/3 neurons and their dendritic spines. Individual neurons with aligned somatic responses received a mixture of monocular and binocular synaptic inputs. Surprisingly, monocular pathways alone could not account for somatic alignment because ipsilateral monocular inputs poorly matched somatic preference. Binocular inputs exhibited different degrees of interocular alignment, and those with a high degree of alignment (congruent) had greater selectivity and somatic specificity. While congruent inputs were similar to others in measures of strength, simulations show that the number of active congruent inputs predicts aligned somatic output. Our study suggests that coherent binocular responses derive from connectivity biases that support functional amplification of aligned signals within a heterogeneous binocular intracortical network.


Assuntos
Furões , Córtex Visual , Animais , Neurônios/fisiologia , Estimulação Luminosa/métodos , Visão Binocular/fisiologia , Córtex Visual/fisiologia
18.
J Invest Surg ; 35(4): 758-767, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34157922

RESUMO

BACKGROUND: Microsurgical transplantation of vascularized lymph nodes (VLNT) or lymphatic vessels (VLVT) alongside derivative lymphaticovenous procedures are promising approaches for treatment of lymphedema. However, clinically relevant training models for mastering these techniques are still lacking. Here we describe a new training model in human cadaver and validate its use as training tool for microsurgical lymphatic reconstruction. METHODS: 10 surgeons with previous exposure to microsurgery were trained in a controlled environment. Lymphatic vessel mapping and dissection in 4 relevant body regions, harvesting of five different VLNTs and one VLVT were performed in 5 fresh-frozen cadavers. The number of lymphatic vessels and lymph nodes for each VLNT were recorded. Finally, the efficacy of this model as training tool was validated using the Dundee Ready Education Environment Measure (DREEM). RESULTS: The average cumulative DREEM score over each category was 30,75 (max = 40) while individual scoring for each relevant category revealed highly positive ratings from the perspective of teaching (39,3), training 40,5 (max = 48) and self perception of the training 30,5 (max = 32) from all participants. The groin revealed the highest number of lymphatic vessels (3.2 ± 0.29) as all other regions on the upper extremity, while the gastroepiploic VLNT had the highest number of lymph nodes (4.2 ± 0.37). CONCLUSIONS: This human cadaver model represents a new, reproducible "all-in-one" tool for effective training in lymphatic microsurgery. Its unique diligence in accurately reproducing human lymphatic anatomy, should make this model worth considering for each microsurgeon willing to approach lymphatic reconstruction.


Assuntos
Vasos Linfáticos , Linfedema , Anastomose Cirúrgica/métodos , Cadáver , Humanos , Linfonodos/cirurgia , Vasos Linfáticos/patologia , Vasos Linfáticos/cirurgia , Linfedema/patologia , Linfedema/cirurgia , Microcirurgia/métodos
19.
Am J Health Promot ; 36(2): 288-295, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34719985

RESUMO

PURPOSE: The purpose of this study was to qualitatively explore perceptions related to COVID-19 vaccination intention among African American and Latinx participants and suggest intervention strategies. APPROACH: Ninety minute virtual focus groups (N = 8), segmented by county, race and ethnicity were conducted with stakeholders from 3 vulnerable Alabama counties. PARTICIPANTS: Participants (N = 67) were primarily African American and Latinx, at least 19 years, and residents or stakeholders in Jefferson, Mobile, and Dallas counties. SETTING: Focus groups took place virtually over Zoom. METHODS: The semi-structured guide explored perceptions of COVID-19, with an emphasis on barriers and facilitators to vaccine uptake. Focus groups lasted approximately 90 minutes and were audio recorded, transcribed, and analyzed by a team of 3 investigators, according to the guidelines of Thematic Analysis using NVivo 12. To provide guidance in the development of interventions to decrease vaccine hesitancy, we examined how themes fit with the constructs of the Health Belief Model. RESULTS: We found that primary themes driving COVID-19 vaccine hesitancy, ordered from most to least discussed, are mistrust, fear, and lack of information. Additionally, interventions to decrease vaccine hesitancy should be multi-modal, community engaged, and provide consistent, comprehensive messages delivered by trusted sources.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Negro ou Afro-Americano , Humanos , SARS-CoV-2 , Hesitação Vacinal
20.
Exp Aging Res ; 36(1): 1-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20054724

RESUMO

This study investigated whether the difficulties older adults experience when recognizing specific emotions from facial expressions also occur with vocal expressions of emotion presented in isolation or in combination with facial expressions. When matching vocal expressions of six emotions to emotion labels, older adults showed worse performance on sadness and anger. When matching vocal expressions to facial expressions, older adults showed worse performance on sadness, anger, happiness, and fear. Older adults' poorer performance when matching faces to voices was independent of declines in fluid ability. Results are interpreted with reference to the neuropsychology of emotion recognition and the aging brain.


Assuntos
Envelhecimento/psicologia , Emoções/fisiologia , Expressão Facial , Processos Mentais/fisiologia , Percepção da Fala/fisiologia , Estimulação Acústica/métodos , Estimulação Acústica/psicologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Ira/fisiologia , Medo/fisiologia , Feminino , Felicidade , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
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