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1.
J Phys Chem A ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38968412

ABSTRACT

Kinetics of the lanthanide cations (Ln+ = La+-Lu+ excluding Pm+) reacting with molecular oxygen were measured in a selected-ion flow tube apparatus from 300 to 600 K. Where exothermic, these reactions occur efficiently, producing LnO+ + O. The reactions display positive temperature dependences consistent with Arrhenius equation behavior and show small activation energies (0-2 kJ mol-1) that are strongly correlated to promotion energies of the Ln+ atoms. Reanalysis of literature data on neutral Ln + O2 reactions show a similar correlation with slightly larger activation energies (0-10 kJ mol-1). The data are explained by a common mechanism controlling oxidation by molecular oxygen in these systems, as well as in gas-phase reactions of transition metal and posttransition metal cluster anions, neutral clusters deposited on surfaces, and for oxygen incident on metal surfaces. It is posited that across these systems, the height of an early barrier along the reaction coordinate is predictable based on knowledge of the electronic states of the reactants and may be used to either promote or inhibit oxygen activation.

3.
Q J Econ ; 139(3): 1827-1878, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38974527

ABSTRACT

In the 1960s, two landmark statutes-the Equal Pay and Civil Rights Acts-targeted the long-standing practice of employment discrimination against U.S. women. For the next 15 years, the gender gap in median earnings among full-time, full-year workers changed little, leading many scholars to conclude that the legislation was ineffectual. This article revisits this conclusion using two research designs, which leverage (i) cross-state variation in preexisting state equal pay laws and (ii) variation in the 1960 gender gap across occupation-industry-state-group cells to capture differences in the legislation's incidence. Both designs suggest that federal antidiscrimination legislation led to striking gains in women's relative wages, which were concentrated among below-median wage earners. These wage gains offset preexisting labor market forces, which worked to depress women's relative pay growth, resulting in the apparent stability of the gender gap at the median and mean in the 1960s and 1970s. The data show little evidence of short-term changes in women's employment but suggest that firms reduced their hiring and promotion of women in the medium to long term. The historical record points to the key role of the Equal Pay Act in driving these changes.

4.
AIDS Behav ; 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38995441

ABSTRACT

Loss to follow-up (LTFU) in high-resolution anoscopy (HRA) programs jeopardizes the procedure's potential to help prevent anal cancer. We explored quality improvement factors to understand how to address this LTFU. Using the transtheoretical COM-B Model (Capability, Opportunity, Motivation, and Behavior) and a sequential explanatory mixed-methods design, we surveyed and interviewed 13 patients who remained engaged in HIV care but who delayed their HRA monitoring or treatment visits in the same community clinic, and 6 HRA clinicians and medical assistants. Analyses involved descriptive statistics and rapid qualitative analysis. Patients were racially, ethnically, and economically representative of the LTFU population, and were generally experienced with HRA (Mean HRA visits = 4.6, SD = 2.8, mdn = 3). Providers were experienced clinicians and medical assistants (Mean years providing HRA = 6.0, SD = 2.2). Analyses revealed two primary, related barriers: (A) motivational barriers such as physical pain, discomfort, embarrassment, and anxiety; which were largely borne from (B) opportunity barriers such as difficulties with scheduling, inconsistent after-care (particularly for pain and discomfort), anxiety-inducing exam rooms and equipment, and internalized and anticipated stigma. Capability barriers, such as limited health literacy about HRA, were less common and, like motivational barriers, linked to opportunity barriers. Participants recommended potential facilitators, including easier scheduling, standardization of pain management and after-care services, and examination room modifications to reduce anxiety. To retain HRA patients in community settings, interventions should address social and physical opportunity barriers that strongly determine motivational and capability barriers. Improving convenience, standardizing pain management, and introducing stigma interventions specific to HRA, could alleviate both motivational and capability barriers.


RESUMEN: La pérdida de seguimiento (LTFU) en los programas de anoscopia de alta resolución (HRA) pone en peligro el potencial del procedimiento para ayudar a prevenir el cáncer anal. Exploramos factores de mejora de la calidad para comprender cómo abordar este LTFU. Utilizando el modelo COM-B transteórico (Capacidad, Oportunidad, Motivación y Comportamiento) y un diseño de métodos mixtos explicativos secuenciales, encuestamos y entrevistamos a 13 pacientes que permanecieron involucrados en la atención del VIH pero que retrasaron sus visitas de seguimiento o tratamiento de la HRA en la misma clínica comunitaria y 6 médicos y asistentes médicos de la HRA. Los análisis involucraron estadísticas descriptivas y análisis cualitativo rápido. Los pacientes eran representativos de la población LTFU en cuanto a raza, etnia, y estatus económico. En general, tenían experiencia con HRA (visitas HRA media = 4,6, DE = 2,8, mdn = 3). Los proveedores eran médicos y asistentes médicos con experiencia (promedio de años proporcionando HRA = 6,0, DE = 2,2). Los análisis revelaron dos barreras principales relacionadas: (A) barreras motivacionales como el dolor físico, la incomodidad, la vergüenza y la ansiedad; que se debieron en gran medida a (B) barreras de oportunidad, como dificultades con la programación, cuidados posteriores inconsistentes (particularmente para el dolor y el malestar), salas de examen y equipos que inducen ansiedad, y estigma internalizado y anticipado. Las barreras a la capacidad, como la limitada alfabetización sanitaria sobre la HRA, fueron menos comunes y, al igual que las barreras motivacionales, estaban vinculadas a las barreras de oportunidades. Los participantes recomendaron posibles facilitadores, incluida una programación más sencilla, la estandarización del manejo del dolor y los servicios de cuidados posteriores, y modificaciones en la sala de examen para reducir la ansiedad. Para retener a los pacientes de HRA en entornos comunitarios, las intervenciones deben abordar las barreras de oportunidades sociales y físicas que determinan fuertemente las barreras motivacionales y de capacidad. Mejorar la conveniencia, estandarizar el manejo del dolor e introducir intervenciones de estigma específicas para la HRA podría aliviar las barreras tanto motivacionales como de capacidad.

5.
J Vis Exp ; (208)2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38949382

ABSTRACT

Lung transplantation is hampered by the lack of suitable donors. Previously, donors that were thought to be marginal or inadequate were discarded. However, new and exciting technology, such as ex vivo lung perfusion (EVLP), offers lung transplant providers extended assessment for marginal donor allografts. This dynamic assessment platform has led to an increase in lung transplantation and has allowed providers to use donors that were previously discarded, thus expanding the donor pool. Current perfusion techniques use cellular or acellular perfusates, and both have distinct advantages and disadvantages. Perfusion composition is critical to maintaining a homeostatic environment, providing adequate metabolic support, decreasing inflammation and cellular death, and ultimately improving organ function. Perfusion solutions must contain sufficient protein concentration to maintain appropriate oncotic pressure. However, current perfusion solutions often lead to fluid extravasation through the pulmonary endothelium, resulting in inadvertent pulmonary edema and damage. Thus, it is necessary to develop novel perfusion solutions that prevent excessive damage while maintaining proper cellular homeostasis. Here, we describe the application of a polymerized human hemoglobin (PolyhHb)-based oxygen carrier as a perfusate and the protocol in which this perfusion solution can be tested in a model of rat EVLP. The goal of this study is to provide the lung transplant community with key information in designing and developing novel perfusion solutions, as well as the proper protocols to test them in clinically relevant translational transplant models.


Subject(s)
Hemoglobins , Lung Transplantation , Lung , Perfusion , Animals , Rats , Lung Transplantation/methods , Hemoglobins/chemistry , Perfusion/methods , Lung/metabolism , Humans , Oxygen/metabolism , Blood Substitutes/pharmacology , Blood Substitutes/chemistry , Male , Organ Preservation Solutions/chemistry
6.
BJS Open ; 8(1)2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38949628

ABSTRACT

BACKGROUND: Textbook outcomes are composite outcome measures that reflect the ideal overall experience for patients. There are many of these in the elective surgery literature but no textbook outcomes have been proposed for patients following emergency laparotomy. The aim was to achieve international consensus amongst experts and patients for the best Textbook Outcomes for non-trauma and trauma emergency laparotomy. METHODS: A modified Delphi exercise was undertaken with three planned rounds to achieve consensus regarding the best Textbook Outcomes based on the category, number and importance (Likert scale of 1-5) of individual outcome measures. There were separate questions for non-trauma and trauma. A patient engagement exercise was undertaken after round 2 to inform the final round. RESULTS: A total of 337 participants from 53 countries participated in all three rounds of the exercise. The final Textbook Outcomes were divided into 'early' and 'longer-term'. For non-trauma patients the proposed early Textbook Outcome was 'Discharged from hospital without serious postoperative complications (Clavien-Dindo ≥ grade III; including intra-abdominal sepsis, organ failure, unplanned re-operation or death). For trauma patients it was 'Discharged from hospital without unexpected transfusion after haemostasis, and no serious postoperative complications (adapted Clavien-Dindo for trauma ≥ grade III; including intra-abdominal sepsis, organ failure, unplanned re-operation on or death)'. The longer-term Textbook Outcome for both non-trauma and trauma was 'Achieved the early Textbook Outcome, and restoration of baseline quality of life at 1 year'. CONCLUSION: Early and longer-term Textbook Outcomes have been agreed by an international consensus of experts for non-trauma and trauma emergency laparotomy. These now require clinical validation with patient data.


Subject(s)
Delphi Technique , Laparotomy , Humans , Laparotomy/adverse effects , Postoperative Complications/etiology , Consensus , Emergencies , Outcome Assessment, Health Care
7.
Am J Transplant ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38951053

ABSTRACT

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

8.
Neurosurgery ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38990004

ABSTRACT

BACKGROUND AND OBJECTIVES: The "July Effect" hypothesizes increased morbidity and mortality after the addition of inexperienced physicians at the beginning of an academic year. However, the impact of newer members on neurosurgical teams managing patients with traumatic brain injury (TBI) has yet to be examined. This study conducted a nationwide analysis to evaluate the existence of the "July Effect" in the setting of patients with TBI. METHODS: The Healthcare Cost and Utilization Project Central Distributor's National Inpatient Sample data set was queried for patients with TBI using International Classification of Diseases (ICD)-9 and ICD-10 codes. Discharges were included for diagnoses of traumatic epidural, subdural, or subarachnoid hemorrhages. Only patients treated at teaching hospitals were included to ensure resident involvement in care. Patients were grouped into July admission and non-July admission cohorts. A subgroup of patients with neurotrauma undergoing any form of cranial surgery was created. Perioperative variables were recorded. Rates of different complications were assayed. Groups were compared using χ2 tests (qualitative variables) and t-tests or Mann-Whitney U-tests (quantitative variables). Logistic regression was used for binary variables. Gamma log-linked regression was used for continuous variables. RESULTS: The National Inpatient Sample database yielded a weighted average of 3 160 452 patients, of which 312 863 (9.9%) underwent surgical management. Patients admitted to the hospital in July had a 5% decreased likelihood of death (P = .027), and a 5.83% decreased likelihood of developing a complication (P < .001) compared with other months of the year. July admittance to a hospital showed no significant impact on mean length of stay (P = .392) or routine discharge (P = .147). Among patients with TBI who received surgical intervention, July admittance did not significantly affect the likelihood of death (P = .053), developing a complication (P = .477), routine discharge (P = .986), or mean length of stay (P = .385). CONCLUSION: The findings suggested that there is no "July Effect" on patients with TBI treated at teaching hospitals in the United States.

9.
Surg Endosc ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38951240

ABSTRACT

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

10.
Methods Mol Biol ; 2805: 113-124, 2024.
Article in English | MEDLINE | ID: mdl-39008177

ABSTRACT

The extracellular matrix (ECM) provides dynamic structural and molecular signals that affect the form and function of developing tissues. In order to parse how the individual features of the ECM impact cell- and tissue-level behavior during development, engineered culture models should reproduce key structural and molecular features of native ECM. Here, we describe a protocol for bioprinting epithelial cell aggregates embedded within a collagen-Matrigel ink in order to study the dynamic interplay between epithelial tissues and aligned networks of type I collagen fibers. Collagen fiber alignment and geometry can be spatially controlled by modulating the printing speed, nozzle geometry, surface chemistry, and degree of molecular crowding in the printing ink. We provide detailed procedures for generating epithelial cell aggregates, microextrusion printing collagen-Matrigel bioinks, culturing the three-dimensional (3D)-printed tissues, and imaging 3D-printed collagen-Matrigel constructs.


Subject(s)
Bioprinting , Collagen , Epithelial Cells , Extracellular Matrix , Hydrogels , Printing, Three-Dimensional , Tissue Engineering , Bioprinting/methods , Hydrogels/chemistry , Collagen/chemistry , Collagen/metabolism , Tissue Engineering/methods , Epithelial Cells/cytology , Epithelial Cells/metabolism , Extracellular Matrix/metabolism , Extracellular Matrix/chemistry , Animals , Morphogenesis , Humans , Proteoglycans/chemistry , Proteoglycans/metabolism , Tissue Scaffolds/chemistry , Laminin/chemistry , Drug Combinations , Dogs , Epithelium/metabolism , Epithelium/growth & development
11.
Nat Med ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965435

ABSTRACT

Differential diagnosis of dementia remains a challenge in neurology due to symptom overlap across etiologies, yet it is crucial for formulating early, personalized management strategies. Here, we present an artificial intelligence (AI) model that harnesses a broad array of data, including demographics, individual and family medical history, medication use, neuropsychological assessments, functional evaluations and multimodal neuroimaging, to identify the etiologies contributing to dementia in individuals. The study, drawing on 51,269 participants across 9 independent, geographically diverse datasets, facilitated the identification of 10 distinct dementia etiologies. It aligns diagnoses with similar management strategies, ensuring robust predictions even with incomplete data. Our model achieved a microaveraged area under the receiver operating characteristic curve (AUROC) of 0.94 in classifying individuals with normal cognition, mild cognitive impairment and dementia. Also, the microaveraged AUROC was 0.96 in differentiating the dementia etiologies. Our model demonstrated proficiency in addressing mixed dementia cases, with a mean AUROC of 0.78 for two co-occurring pathologies. In a randomly selected subset of 100 cases, the AUROC of neurologist assessments augmented by our AI model exceeded neurologist-only evaluations by 26.25%. Furthermore, our model predictions aligned with biomarker evidence and its associations with different proteinopathies were substantiated through postmortem findings. Our framework has the potential to be integrated as a screening tool for dementia in clinical settings and drug trials. Further prospective studies are needed to confirm its ability to improve patient care.

12.
J Cell Sci ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963001

ABSTRACT

Semaphorin6A (Sema6A) is a repulsive guidance molecule that plays many roles in central nervous system, heart, and bone development, as well as immune system responses and cell signaling in cancer. Loss of Sema6A or its receptor PlexinA2 in zebrafish leads to smaller eyes and improper retinal patterning. Here we investigate a potential role for the Sema6A intracellular domain in zebrafish eye development and dissect which phenotypes rely on forward signaling and which rely on reverse signaling. We performed rescue experiments on zebrafish Sema6A morphants with either full-length Sema6A (Sema6A-FL) or Sema6A lacking its intracellular domain (Sema6A-ΔC). We identified that the intracellular domain is not required for eye size and retinal patterning, however it is required for retinal integrity, the number and end feet strength of Müller glia and protecting against retinal cell death. This novel function for the intracellular domain suggests a role for Sema6A reverse signaling in zebrafish eye development.

13.
Anal Chem ; 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39012783

ABSTRACT

Structural mass spectrometry (MS) techniques are fast and sensitive analytical methods to identify noncovalent guest/host complexation phenomena for desirable solution-phase properties. Current MS-based studies on guest/host complexes of drug and drug-like molecules are sparse, and there is limited guidance on how to interpret MS information in the context of host nanoencapsulation and inclusion. Here, we use structural MS strategies, combining energy-resolved MS (ERMS), ion mobility-MS (IM-MS), and computational modeling, to characterize 14 chemically distinct drug and drug-like compounds for their propensity to form guest/host complexes with the widely used excipient, beta-cyclodextrin (ßCD). The majority (11/14) yielded a 1:1 guest/host complex, and ion mobility collision cross section (CCS) analysis provided subtle evidence of gas-phase compaction of complexes in both polarities. The three distinct dissociation channels observed in ERMS (i.e., charged ßCD, charged guest, and partial guest loss) were used to direct charge-site assignments for computational modeling, and structural candidates were prioritized using helium-derived CCS measurements combined with root-mean-square distance analysis. The combined analytical information from ERMS, IM-MS, and computational modeling suggested that the majority of anhydrous complexes are inclusion complexes with ßCD. Taken together, this work demonstrates a roadmap for how multiple MS-based analytical measurements can be combined to interpret the structures that guest/host complexes adopt in the absence of water.

14.
Cureus ; 16(5): e59569, 2024 May.
Article in English | MEDLINE | ID: mdl-38832206

ABSTRACT

Introduction As primary care practices transition to a post-pandemic system of healthcare, it is important to recognize the benefits of offering telehealth services. Little research is available on the effectiveness of telehealth visits for managing acute illnesses or conditions in primary care practice. Methods Using the reporting functionality in the Epic™ electronic health record (EHR) (Epic Systems Corporation, Verona), a report was generated to identify all telehealth visit encounters that were completed in a family medicine clinic from March 1, 2020, to June 30, 2020. The report identified patients who had an acute complaint and required an in-office visit within 60 days of the telehealth encounter. If the patient required a face-to-face visit, that was not directed by the provider, the chart was reviewed to determine whether the diagnosis changed. The primary outcome was returning for a face-to-face visit within 30 days of the telehealth visit for the same acute need. Results The cohort included 349 telehealth visits for 303 patients. For patients who had more than one telehealth visit, only the first one was included in the analysis. Among the 303 patients, 50 (16.5%) returned for a face-to-face visit within 30 days of the telehealth visit (95% confidence interval: 12.5%-21.2%), and 71 (23.6%) returned for a telehealth visit within 60 days (95% confidence interval: 18.9%-28.8%). Furthermore, 19 of the 50 patients (38%) that returned for a face-to-face visit did not have a change in diagnosis, and, in some instances, the diagnosis made on the telehealth visit was only slightly different from the face-to-face visit. Discussion and conclusion Telehealth, specifically two-way, synchronous, interactive patient-provider communication through audio and video equipment, for acute care needs in a primary care practice helps reduce the need for in-person visits and can address patient complaints without the need for in-person follow-up.

15.
Microb Genom ; 10(6)2024 Jun.
Article in English | MEDLINE | ID: mdl-38860884

ABSTRACT

As public health laboratories expand their genomic sequencing and bioinformatics capacity for the surveillance of different pathogens, labs must carry out robust validation, training, and optimization of wet- and dry-lab procedures. Achieving these goals for algorithms, pipelines and instruments often requires that lower quality datasets be made available for analysis and comparison alongside those of higher quality. This range of data quality in reference sets can complicate the sharing of sub-optimal datasets that are vital for the community and for the reproducibility of assays. Sharing of useful, but sub-optimal datasets requires careful annotation and documentation of known issues to enable appropriate interpretation, avoid being mistaken for better quality information, and for these data (and their derivatives) to be easily identifiable in repositories. Unfortunately, there are currently no standardized attributes or mechanisms for tagging poor-quality datasets, or datasets generated for a specific purpose, to maximize their utility, searchability, accessibility and reuse. The Public Health Alliance for Genomic Epidemiology (PHA4GE) is an international community of scientists from public health, industry and academia focused on improving the reproducibility, interoperability, portability, and openness of public health bioinformatic software, skills, tools and data. To address the challenges of sharing lower quality datasets, PHA4GE has developed a set of standardized contextual data tags, namely fields and terms, that can be included in public repository submissions as a means of flagging pathogen sequence data with known quality issues, increasing their discoverability. The contextual data tags were developed through consultations with the community including input from the International Nucleotide Sequence Data Collaboration (INSDC), and have been standardized using ontologies - community-based resources for defining the tag properties and the relationships between them. The standardized tags are agnostic to the organism and the sequencing technique used and thus can be applied to data generated from any pathogen using an array of sequencing techniques. The tags can also be applied to synthetic (lab created) data. The list of standardized tags is maintained by PHA4GE and can be found at https://github.com/pha4ge/contextual_data_QC_tags. Definitions, ontology IDs, examples of use, as well as a JSON representation, are provided. The PHA4GE QC tags were tested, and are now implemented, by the FDA's GenomeTrakr laboratory network as part of its routine submission process for SARS-CoV-2 wastewater surveillance. We hope that these simple, standardized tags will help improve communication regarding quality control in public repositories, in addition to making datasets of variable quality more easily identifiable. Suggestions for additional tags can be submitted to PHA4GE via the New Term Request Form in the GitHub repository. By providing a mechanism for feedback and suggestions, we also expect that the tags will evolve with the needs of the community.


Subject(s)
Computational Biology , Public Health , Quality Control , Humans , Computational Biology/methods , Information Dissemination/methods , Reproducibility of Results , Molecular Sequence Annotation/methods , Genomics/methods , Software
16.
Cells Tissues Organs ; 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38934132

ABSTRACT

Localized delivery of angiogenesis-promoting factors such as small molecules, nucleic acids, peptides, and proteins to promote the repair and regeneration of damaged tissues remains a challenge in vascular tissue engineering. Current delivery methods such as direct administration of therapeutics can fail to maintain the necessary sustained release profile and often rely on supraphysiologic doses to achieve the desired therapeutic effect. By implementing a microparticle delivery system, localized delivery can be coupled with sustained controlled release to mitigate the risks involved with the high dosages currently required from direct therapeutic administration. For this purpose, poly(lactic-co-glycolic acid) microparticles were fabricated via antisolvent microencapsulation and the loading, release, and delivery of model angiogenic molecules specifically a small molecule, nucleic acid, and protein, were assessed in vitro using microvascular fragments (MVF). The microencapsulation approach utilized enabled rapid spherical particle formation and encapsulation of model drugs of different sizes, all in one method. The addition of a fibrin scaffold, required for the culture of the MVFs, reduced the initial burst of model drugs, observed in release profiles from PLGA alone. Lastly, in vitro studies using MVFs demonstrated that higher concentrations of microparticles led to greater co-localization of the model therapeutic (miRNA) with MVFs, which is vital for targeted delivery methods. It was also found that the biodistribution of miRNA using the delivered microparticle system was enhanced compared to direct administration. Overall, poly(lactic-co-glycolic acid) microparticles, formulated and loaded with model therapeutic compounds in one step, resulted in improved biodistribution in a model of the vasculature leading to a future in translational revascularization.

17.
J Cell Biol ; 223(9)2024 Sep 02.
Article in English | MEDLINE | ID: mdl-38842573

ABSTRACT

Extracellular vesicles (EVs) are released by many cell types, including neurons, carrying cargoes involved in signaling and disease. It is unclear whether EVs promote intercellular signaling or serve primarily to dispose of unwanted materials. We show that loss of multivesicular endosome-generating endosomal sorting complex required for transport (ESCRT) machinery disrupts release of EV cargoes from Drosophila motor neurons. Surprisingly, ESCRT depletion does not affect the signaling activities of the EV cargo Synaptotagmin-4 (Syt4) and disrupts only some signaling activities of the EV cargo evenness interrupted (Evi). Thus, these cargoes may not require intercellular transfer via EVs, and instead may be conventionally secreted or function cell-autonomously in the neuron. We find that EVs are phagocytosed by glia and muscles, and that ESCRT disruption causes compensatory autophagy in presynaptic neurons, suggesting that EVs are one of several redundant mechanisms to remove cargoes from synapses. Our results suggest that synaptic EV release serves primarily as a proteostatic mechanism for certain cargoes.


Subject(s)
Drosophila Proteins , Drosophila melanogaster , Endosomal Sorting Complexes Required for Transport , Extracellular Vesicles , Motor Neurons , Signal Transduction , Synapses , Animals , Endosomal Sorting Complexes Required for Transport/metabolism , Endosomal Sorting Complexes Required for Transport/genetics , Extracellular Vesicles/metabolism , Drosophila Proteins/metabolism , Drosophila Proteins/genetics , Drosophila melanogaster/metabolism , Synapses/metabolism , Motor Neurons/metabolism , Autophagy , Synaptotagmins/metabolism , Synaptotagmins/genetics , Neuroglia/metabolism
18.
bioRxiv ; 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38895415

ABSTRACT

G protein-coupled receptors (GPCRs) are efficient Guanine nucleotide exchange factors (GEFs) and exchange GDP to GTP on the Gα subunit of G protein heterotrimers in response to various extracellular stimuli, including neurotransmitters and light. GPCRs primarily broadcast signals through activated G proteins, GαGTP, and free Gßγ, and are major disease drivers. Evidence shows that the ambient low threshold signaling required for cells is likely supplemented by signaling regulators such as non-GPCR GEFs and Guanine nucleotide Dissociation Inhibitors (GDIs). Activators of G protein Signaling 3 (AGS3) are recognized as a GDI involved in multiple health and disease-related processes. Nevertheless, understanding of AGS3 is limited, and no significant information is available on its structure-function relationship or signaling regulation in living cells. Here, we employed in silico structure-guided engineering of a novel optogenetic GDI, based on the AGS3's G protein regulatory (GPR) motif, to understand its GDI activity and induce standalone Gßγ signaling in living cells on optical command. Our results demonstrate that plasma membrane recruitment of OptoGDI efficiently releases Gßγ, and its subcellular targeting generated localized PIP3 and triggered macrophage migration. Therefore, we propose OptoGDI as a powerful tool for optically dissecting GDI-mediated signaling pathways and triggering GPCR-independent Gßγ signaling in cells and in vivo.

19.
Addict Biol ; 29(6): e13420, 2024 06.
Article in English | MEDLINE | ID: mdl-38898729

ABSTRACT

Alcohol consumption occurring in a social or solitary setting often yields different behavioural responses in human subjects. For example, social drinking is associated with positive effects while solitary drinking is linked to negative effects. However, the neurobiological mechanism by which the social environment during alcohol intake impacts on behavioural responses remains poorly understood. We investigated whether distinct social environments affect behavioural responses to ethanol and the role of the dopamine system in this phenomenon in the fruit fly Drosophila melanogaster. The wild-type Canton-S (CS) flies showed higher locomotor response when exposed to ethanol in a group setting than a solitary setting, and there was no difference in females and males. Dopamine signalling is crucial for the locomotor stimulating effect of ethanol. When subjected to ethanol exposure alone, the dopamine transport mutant flies fumin (fmn) with hyper dopamine displayed the locomotor response similar to CS. When subjected to ethanol in a group setting, however, the fmn's response to the locomotor stimulating effect was substantially augmented compared with CS, indicating synergistic interaction of dopamine signalling and social setting. To identify the dopamine signalling pathway important for the social effect, we examined the flies defective in individual dopamine receptors and found that the D1 receptor dDA1/Dop1R1 is the major receptor mediating the social effect. Taken together, this study underscores the influence of social context on the neural and behavioural responses to ethanol.


Subject(s)
Dopamine , Drosophila Proteins , Drosophila melanogaster , Ethanol , Animals , Ethanol/pharmacology , Dopamine/metabolism , Drosophila melanogaster/drug effects , Male , Female , Drosophila Proteins/genetics , Receptors, Dopamine D1/drug effects , Social Environment , Signal Transduction/drug effects , Locomotion/drug effects , Receptors, Dopamine/drug effects , Receptors, Dopamine/metabolism , Behavior, Animal/drug effects , Central Nervous System Depressants/pharmacology , Social Behavior , Dopamine Plasma Membrane Transport Proteins/drug effects , Dopamine Plasma Membrane Transport Proteins/genetics , Motor Activity/drug effects
20.
Sci Adv ; 10(25): eadj9173, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38905344

ABSTRACT

Sensory neurons in the dorsal root ganglion (DRG) and trigeminal ganglion (TG) are specialized to detect and transduce diverse environmental stimuli to the central nervous system. Single-cell RNA sequencing has provided insights into the diversity of sensory ganglia cell types in rodents, nonhuman primates, and humans, but it remains difficult to compare cell types across studies and species. We thus constructed harmonized atlases of the DRG and TG that describe and facilitate comparison of 18 neuronal and 11 non-neuronal cell types across six species and 31 datasets. We then performed single-cell/nucleus RNA sequencing of DRG from both human and the highly regenerative axolotl and found that the harmonized atlas also improves cell type annotation, particularly of sparse neuronal subtypes. We observed that the transcriptomes of sensory neuron subtypes are broadly similar across vertebrates, but the expression of functionally important neuropeptides and channels can vary notably. The resources presented here can guide future studies in comparative transcriptomics, simplify cell-type nomenclature differences across studies, and help prioritize targets for future analgesic development.


Subject(s)
Ganglia, Spinal , Transcriptome , Trigeminal Ganglion , Animals , Humans , Ganglia, Spinal/cytology , Ganglia, Spinal/metabolism , Trigeminal Ganglion/cytology , Trigeminal Ganglion/metabolism , Single-Cell Analysis/methods , Sensory Receptor Cells/metabolism , Sensory Receptor Cells/cytology , Species Specificity , Mice , Atlases as Topic , Gene Expression Profiling , Rats
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