RESUMO
Understanding how internal states like satiety are connected to animal behavior is a fundamental question in neuroscience. Hydra vulgaris, a freshwater cnidarian with only twelve neuronal cell types, serves as a tractable model system for studying state-dependent behaviors. We find that starved Hydra consistently move towards light, while fed Hydra do not. By modeling this behavior as a set of three sequences of head orientation, jump distance, and jump rate, we demonstrate that the satiety state only affects the rate of the animal jumping to a new position, while the orientation and jump distance are unaffected. These findings yield insights into how internal states in a simple organism, Hydra, affect specific elements of a behavior, and offer general principles for studying the relationship between state-dependent behaviors and their underlying molecular mechanisms.
RESUMO
Mesoscopic calcium imaging enables studies of cell-type specific neural activity over large areas. A growing body of literature suggests that neural activity can be different when animals are free to move compared to when they are restrained. Unfortunately, existing systems for imaging calcium dynamics over large areas in non-human primates (NHPs) are table-top devices that require restraint of the animal's head. Here, we demonstrate an imaging device capable of imaging mesoscale calcium activity in a head-unrestrained male non-human primate. We successfully miniaturize our system by replacing lenses with an optical mask and computational algorithms. The resulting lensless microscope can fit comfortably on an NHP, allowing its head to move freely while imaging. We are able to measure orientation columns maps over a 20 mm2 field-of-view in a head-unrestrained macaque. Our work establishes mesoscopic imaging using a lensless microscope as a powerful approach for studying neural activity under more naturalistic conditions.
Assuntos
Cálcio , Microscopia , Masculino , Animais , PrimatasRESUMO
Miniaturized neuromodulation systems could improve the safety and reduce the invasiveness of bioelectronic neuromodulation. However, as implantable bioelectronic devices are made smaller, it becomes difficult to store enough power for long-term operation in batteries. Here, we present a battery-free epidural cortical stimulator that is only 9 millimeters in width yet can safely receive enough wireless power using magnetoelectric antennas to deliver 14.5-volt stimulation bursts, which enables it to stimulate cortical activity on-demand through the dura. The device has digitally programmable stimulation output and centimeter-scale alignment tolerances when powered by an external transmitter. We demonstrate that this device has enough power and reliability for real-world operation by showing acute motor cortex activation in human patients and reliable chronic motor cortex activation for 30 days in a porcine model. This platform opens the possibility of simple surgical procedures for precise neuromodulation.
Assuntos
Fontes de Energia Elétrica , Córtex Motor , Humanos , Animais , Suínos , Reprodutibilidade dos TestesRESUMO
Severe infections associated with the use of strong immunosuppressive medication are a leading cause of morbidity and mortality in patients with ANCA vasculitis (AV). While guidelines conditionally recommend trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis for Pneumocystis jirovecii pneumonia in AV patients, robust evidence on prophylaxis strategies is lacking. This scoping review aimed to assess the existing evidence on infection prophylaxis in AV patients, identify knowledge gaps, and guide future study design. A comprehensive search of six databases and relevant references identified original studies in English from January 1, 2000, to July 31, 2020. Inclusion criteria encompassed studies evaluating the impact of any antimicrobial prophylaxis strategy on infection-related outcomes in AV patients receiving immunosuppressive treatment. Studies were screened by four researchers using a blinded approach. Data was extracted by two reviewers, with differences resolved via consensus in consultation with a third reviewer. Nineteen studies met inclusion criteria, including two randomized trials and 17 cohort studies, with TMP-SMX being the most commonly assessed prophylactic strategy. The studies varied in sample sizes, outcomes measured, prophylactic strategies employed, and proportion of patients who received the regimen. Most cohort studies included no or limited control of potential confounding factors. This scoping review suggests significant variation in AV patients' receipt of TMP-SMX and alternative infection prophylaxis approaches. Observational studies using large secondary healthcare databases with rigorous designs are needed to provide high-quality evidence of the real-world effectiveness of antimicrobial prophylactic regimens, to improve clinical decision-making and quality of care for AV patients receiving immunosuppressive treatment.
Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Pneumonia por Pneumocystis , Combinação Trimetoprima e Sulfametoxazol , Humanos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Pneumonia por Pneumocystis/prevenção & controle , Imunossupressores/uso terapêutico , AntibioticoprofilaxiaRESUMO
Histopathology plays a critical role in the diagnosis and surgical management of cancer. However, access to histopathology services, especially frozen section pathology during surgery, is limited in resource-constrained settings because preparing slides from resected tissue is time-consuming, labor-intensive, and requires expensive infrastructure. Here, we report a deep-learning-enabled microscope, named DeepDOF-SE, to rapidly scan intact tissue at cellular resolution without the need for physical sectioning. Three key features jointly make DeepDOF-SE practical. First, tissue specimens are stained directly with inexpensive vital fluorescent dyes and optically sectioned with ultra-violet excitation that localizes fluorescent emission to a thin surface layer. Second, a deep-learning algorithm extends the depth-of-field, allowing rapid acquisition of in-focus images from large areas of tissue even when the tissue surface is highly irregular. Finally, a semi-supervised generative adversarial network virtually stains DeepDOF-SE fluorescence images with hematoxylin-and-eosin appearance, facilitating image interpretation by pathologists without significant additional training. We developed the DeepDOF-SE platform using a data-driven approach and validated its performance by imaging surgical resections of suspected oral tumors. Our results show that DeepDOF-SE provides histological information of diagnostic importance, offering a rapid and affordable slide-free histology platform for intraoperative tumor margin assessment and in low-resource settings.
Assuntos
Aprendizado Profundo , Microscopia , Corantes Fluorescentes , Hematoxilina , Amarelo de Eosina-(YS)RESUMO
Peripheral nerve interfaces (PNIs) are electrical systems designed to integrate with peripheral nerves in patients, such as following central nervous system (CNS) injuries to augment or replace CNS control and restore function. We review the literature for clinical trials and studies containing clinical outcome measures to explore the utility of human applications of PNIs. We discuss the various types of electrodes currently used for PNI systems and their functionalities and limitations. We discuss important design characteristics of PNI systems, including biocompatibility, resolution and specificity, efficacy, and longevity, to highlight their importance in the current and future development of PNIs. The clinical outcomes of PNI systems are also discussed. Finally, we review relevant PNI clinical trials that were conducted, up to the present date, to restore the sensory and motor function of upper or lower limbs in amputees, spinal cord injury patients, or intact individuals and describe their significant findings. This review highlights the current progress in the field of PNIs and serves as a foundation for future development and application of PNI systems.
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Amputados , Nervos Periféricos , Humanos , Amputação Cirúrgica , Eletrodos , Paralisia/cirurgiaRESUMO
INTRODUCTION: Nursing home (NH) residents with limited life expectancy (LLE) who are intensely treated for hyperlipidemia, hypertension, or diabetes may benefit from deprescribing. OBJECTIVE: This study sought to describe NH clinician and family caregiver perspectives on key influences on deprescribing decisions for chronic disease medications in NH residents near the end of life. METHODS: We recruited family caregivers of veterans who recently died in a Veterans Affairs (VA) NH, known as community living centers (CLCs), and CLC healthcare clinicians (physicians, nurse practitioners, physician assistants, pharmacists, registered nurses). Respondents completed semi-structured interviews about their experiences with deprescribing statin, antihypertensive, and antidiabetic medications for residents near end of life. We conducted thematic analysis of interview transcripts to identify key themes regarding influences on deprescribing decisions. RESULTS: Thirteen family caregivers and 13 clinicians completed interviews. Key themes included (1) clinicians and caregivers both prefer to minimize drug burden; (2) clinical factors strongly influence deprescribing of chronic disease medications, with differences in how clinicians and caregivers weigh specific factors; (3) caregivers trust and rely on clinicians to make deprescribing decisions; (4) clinicians perceive caregiver involvement and buy-in as essential to deprescribing decisions, which requires time and effort to obtain; and (5) clinicians perceive conflicting care from other clinicians as a barrier to deprescribing. CONCLUSIONS: Findings suggest a need for efforts to encourage communication with and education for family caregivers of residents with LLE about deprescribing, and to foster better collaboration among clinicians in CLC and non-CLC settings.
Assuntos
Cuidadores , Desprescrições , Humanos , Idoso , Casas de Saúde , Morte , Doença CrônicaRESUMO
Two-dimensional (2D) films of conjugated porous organic polymers (C-POPs) can translate the rich in-plane functionalities of conjugated frameworks into diverse optical and electronic applications while addressing the processability issues of their crystalline analogs for adaptable device architectures. However, the lack of facile single-step synthetic routes to obtain large-area high-quality films of 2D-C-POPs has limited their application possibilities so far. Here, we report the synthesis of four mechanically robust imine-linked 2D-C-POP free-standing films using a single-step fast condensation route that is scalable and tunable. The rigid covalently bonded 2D structures of the C-POP films offer high stability for volatile gas sensing in harsh environments while simultaneously enhancing site accessibility for gas molecules due to mesoporosity by structural design. Structurally, all films were composed of exfoliable layers of 2D polymeric nanosheets (NSs) that displayed anisotropy from disordered stacking, evinced by out-of-plane birefringent properties. The tunable in-plane conjugation, different nitrogen centers, and porous structures allow the films to act as ultraresponsive colorimetric sensors for acid sensing via reversible imine bond protonation. All the films could detect hydrogen chloride (HCl) gas down to 0.05 ppm, far exceeding the Occupational Safety and Health Administration's permissible exposure limit of 5 ppm with fast response time and good recyclability. Computational insights elucidated the effect of conjugation and tertiary nitrogen in the structures on the sensitivity and response time of the films. Furthermore, we exploited the exfoliated large 2D NSs and anisotropic optoelectronic properties of the films to adapt them into micro-optical and triboelectric devices to demonstrate their real-time sensing capabilities.