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2.
Spine J ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39053737

RESUMEN

This article explores the critical issue of underrepresentation in spine surgery, specifically addressing racial/ethnic diversity. The paper proposes actionable strategies to enhance diversity within spine surgery through early education and outreach, intentional mentorship and sponsorship, and addressing biases in recruitment and promotion processes. It emphasizes the importance of a supportive culture within spine surgery divisions and practices, advocating for a top-down approach to inclusivity, while underscoring the necessity of continuous evaluation and adaptation of diversity initiatives. By leveraging diverse perspectives, the field of spine surgery can better serve an increasingly heterogeneous population, ultimately improving patient care and healthcare outcomes.

3.
CHEST Pulm ; 2(2)2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38993972

RESUMEN

BACKGROUND: Short-term increases in air pollution are associated with poor asthma and COPD outcomes. Short-term elevations in fine particulate matter (PM2.5) due to wildfire smoke are becoming more common. RESEARCH QUESTION: Are short-term increases in PM2.5 and ozone in wildfire season and in winter inversion season associated with a composite of emergency or inpatient hospitalization for asthma and COPD? STUDY DESIGN AND METHODS: Case-crossover analyses evaluated 63,976 and 18,514 patients hospitalized for primary discharge diagnoses of asthma and COPD, respectively, between January 1999 and March 2022. Patients resided on Utah's Wasatch Front where PM2.5 and ozone were measured by Environmental Protection Agency-based monitors. ORs were calculated using Poisson regression adjusted for weather variables. RESULTS: Asthma risk increased on the same day that PM2.5 increased during wildfire season (OR, 1.057 per + 10 µg/m3; 95% CI, 1.019-1.097; P = .003) and winter inversions (OR, 1.023 per +10 µg/m3; 95% CI, 1.010-1.037; P = .0004). Risk decreased after 1 week, but during wildfire season risk rebounded at a 4-week lag (OR, 1.098 per +10 µg/m3; 95% CI, 1.033-1.167). Asthma risk for adults during wildfire season was highest in the first 3 days after PM2.5 increases, but for children, the highest risk was delayed by 3 to 4 weeks. PM2.5 exposure was weakly associated with COPD hospitalization. Ozone exposure was not associated with elevated risks. INTERPRETATION: In a large urban population, short-term increases in PM2.5 during wildfire season were associated with asthma hospitalization, and the effect sizes were greater than for PM2.5 during inversion season.

4.
Rev Environ Health ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38985132

RESUMEN

Many chemicals associated with unconventional oil and natural gas (UOG) are known toxicants, leading to health concerns about the effects of UOG. Our objective was to conduct a scoping review of the toxicological literature to assess the effects of UOG chemical exposures in models relevant to human health. We searched databases for primary research studies published in English or French between January 2000 and June 2023 on UOG-related toxicology studies. Two reviewers independently screened abstracts and full texts to determine inclusion. Seventeen studies met our study inclusion criteria. Nine studies used solely in vitro models, while six conducted their investigation solely in animal models. Two studies incorporated both types of models. Most studies used real water samples impacted by UOG or lab-made mixtures of UOG chemicals to expose their models. Most in vitro models used human cells in monocultures, while all animal studies were conducted in rodents. All studies detected significant deleterious effects associated with exposure to UOG chemicals or samples, including endocrine disruption, carcinogenicity, behavioral changes and metabolic alterations. Given the plausibility of causal relationships between UOG chemicals and adverse health outcomes highlighted in this review, future risk assessment studies should focus on measuring exposure to UOG chemicals in human populations.

5.
Brain Commun ; 6(4): fcae163, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38978724

RESUMEN

Biallelic expansions of the AAGGG repeat in the replication factor C subunit 1 (RFC1) have recently been described to be responsible for cerebellar ataxia, peripheral neuropathy and vestibular areflexia syndrome. This genetic alteration has also allowed genetic classification in up to one-third of cases with idiopathic sensory neuropathy. Here, we screened a well-characterized cohort of inflammatory neuropathy patients for RFC1 repeat expansions to explore whether RFC1 was increased from background rates and possibly involved in the pathogenesis of inflammatory neuropathy. A total of 259 individuals with inflammatory neuropathy and 243 healthy controls were screened for the AAGGG repeat expansion using short-range flanking PCR and repeat-primed PCR. Cases without amplifiable PCR product on flanking PCR and positive repeat-primed PCR were also tested for the mostly non-pathogenic expansions of the AAAGG and AAAAG repeat units. None of the patients showed biallelic AAGGG expansion of RFC1, and their carrier frequency for AAGGG was comparable with controls [n = 27 (5.2%) and n = 23 (4.7%), respectively; P > 0.5]. Data suggest that the pathologic expansions of AAGGG repeats do not contribute to the development of inflammatory neuropathies nor lead to misdiagnosed cases. Accordingly, routine genetic screening for RFC1 repeat expansion is not indicated in this patient population.

6.
Addict Neurosci ; 112024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38957402

RESUMEN

A preclinical model of cue exposure therapy, cue extinction, reduces cue-induced cocaine seeking that is goal-directed but not habit-like. Goal-directed and habitual behaviors differentially rely on the dorsomedial striatum (DMS) and dorsolateral striatum (DLS), but the effects of cue extinction on dorsal striatal responses to cue-induced drug seeking are unknown. We used fiber photometry in rats trained to self-administer cocaine paired with an audiovisual cue to examine how dorsal striatal intracellular calcium and extracellular dopamine activity differs between goal-directed and habit-like cue-induced cocaine seeking and how it is impacted by cue extinction. After minimal fixed-ratio training, rats showed enhanced DMS and DLS calcium responses to cue-reinforced compared to unreinforced lever presses. After rats were trained on goal-promoting fixed ratio schedules or habit-promoting second-order schedules of reinforcement, different patterns of dorsal striatal calcium and dopamine responses to cue-reinforced lever presses emerged. Rats trained on habit-promoting second-order schedules showed reduced DMS calcium responses and enhanced DLS dopamine responses to cue-reinforced lever presses. Cue extinction reduced calcium responses during subsequent drug seeking in the DMS, but not in the DLS. Therefore, cue extinction may reduce goal-directed behavior through its effects on the DMS, whereas habit-like behavior and the DLS are unaffected.

7.
Birth Defects Res ; 116(7): e2384, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38990107

RESUMEN

BACKGROUND: Primary congenital glaucoma (PCG) affects approximately 1 in 10,000 live born infants in the United States (U.S.). PCG has a autosomal recessive inheritance pattern, and variable expressivity and reduced penetrance have been reported. Likely causal variants in the most commonly mutated gene, CYP1B1, are less prevalent in the U.S., suggesting that alternative genes may contribute to the condition. This study utilized exome sequencing to investigate the genetic architecture of PCG in the U.S. and to identify novel genes and variants. METHODS: We studied 37 family trios where infants had PCG and were part of the National Birth Defects Prevention Study (births 1997-2011), a U.S. multicenter study of birth defects. Samples underwent exome sequencing and sequence reads were aligned to the human reference sample (NCBI build 37/hg19). Variant filtration was conducted under de novo and Mendelian inheritance models using GEMINI. RESULTS: Among candidate variants, CYP1B1 was most represented (five trios, 13.5%). Twelve probands (32%) had potentially pathogenic variants in other genes not previously linked to PCG but important in eye development and/or to underlie Mendelian conditions with potential phenotypic overlap (e.g., CRYBB2, RXRA, GLI2). CONCLUSION: Variation in the genes identified in this population-based study may help to further explain the genetics of PCG.


Asunto(s)
Citocromo P-450 CYP1B1 , Secuenciación del Exoma , Exoma , Glaucoma , Humanos , Glaucoma/genética , Glaucoma/congénito , Citocromo P-450 CYP1B1/genética , Femenino , Masculino , Secuenciación del Exoma/métodos , Estados Unidos , Exoma/genética , Mutación/genética , Predisposición Genética a la Enfermedad , Lactante , Recién Nacido
8.
Gynecol Oncol ; 189: 1-8, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38971004

RESUMEN

OBJECTIVES: Tissue banking procedures have evolved to keep pace with precision medicine, technology, emerging understanding of racial disparities, and regulatory requirements. However, there is little published guidance regarding strategies to create and maintain a successful biorepository. Our objective is to describe the infrastructure and protocols used by our Gynecologic Oncology Tissue Bank. METHODS: Our Tissue Bank was founded in 1992. In August 2022, internal funding was used to modernize the Tissue Bank. We hired three full-time employees, implemented universal screening of patients treated by gynecologic oncology faculty, updated consenting protocols, and standardized communication with providers. Tumor tissue, blood derivatives, ascites, and pleural fluid were collected from eligible, consenting patients and processed. Patient-derived cell lines and organoids were generated. For quality control purposes, one formalin-fixed, paraffin-embedded (FFPE) sample per tissue site was analyzed by a board-certified pathologist. All samples were labeled and tracked in an OpenSpecimen collection protocol and clinically annotated in a secure database. RESULTS: From August 2022 to October 2023, 227 patients (83% white, 15% Black, 1% Asian) were enrolled and 4249 specimens were collected. Adherent cell lines were generated from 15 patients with ovarian cancer and cell suspensions for organoid generation were collected from 46 patients with ovarian cancer. A recharge center was established to self-sustain the Tissue Bank. Samples have been shared with academic and commercial collaborators. CONCLUSIONS: Our Tissue Bank has enrolled a large number of diverse patients, collected numerous specimen types, and collaborated widely. The procedures described here provide guidance for other institutions establishing similar resources.

9.
J Int AIDS Soc ; 27 Suppl 1: e26301, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38965978

RESUMEN

INTRODUCTION: Pharmacy-delivered HIV prevention services might create more options for pregnant women to use HIV prevention tools earlier and more consistently during pregnancy. We quantified preferences for attributes of potential HIV prevention services among women of childbearing age in Western Kenya. METHODS: From June to November 2023, we administered a face-to-face discrete choice experiment survey to women aged 15-44 in Kenya's Homa Bay, Kisumu and Siaya counties. The survey evaluated preferences for HIV prevention services, described by seven attributes: service location, travel time, type of HIV test, sexually transmitted infection (STI) testing, partner HIV testing, pre-exposure prophylaxis (PrEP) and service fee. Participants answered a series of 12-choice questions. Each question asked them to select one of two service options or no services-an opt-out option. We used hierarchical Bayesian modelling levels to estimate each attribute level's coefficient and understand how attributes influenced service choice. RESULTS: Overall, 599 participants completed the survey, among whom the median age was 23 years (IQR: 18-27); 33% were married, 20% had a job and worked regularly, and 52% had been pregnant before. Participants, on average, strongly preferred having any HIV prevention service option over none (opt-out preference weight: -5.84 [95% CI: -5.97, -5.72]). The most important attributes were the availability of PrEP (relative importance 27.04% [95% CI: 25.98%, 28.11%]), followed by STI testing (relative importance 20.26% [95% CI: 19.52%, 21.01%]) and partner HIV testing (relative importance: 16.35% [95% CI: 15.79%, 16.90%]). While, on average, participants preferred obtaining services at the clinic more than pharmacies, women prioritized the availability of PrEP, STI testing and partner HIV testing more than the location or cost. CONCLUSIONS: These findings suggest the importance of providing comprehensive HIV prevention services and ensuring PrEP, STI testing and partner HIV testing are available. If pharmacies can offer these services, women are likely to access those services at pharmacies even if they prefer clinics.


Asunto(s)
Infecciones por VIH , Prioridad del Paciente , Humanos , Femenino , Kenia , Adulto , Infecciones por VIH/prevención & control , Embarazo , Adolescente , Adulto Joven , Prioridad del Paciente/estadística & datos numéricos , Encuestas y Cuestionarios , Farmacias/estadística & datos numéricos , Profilaxis Pre-Exposición/estadística & datos numéricos , Profilaxis Pre-Exposición/métodos
10.
Prog Community Health Partnersh ; 18(2): 259-265, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38946570

RESUMEN

BACKGROUND: People with intellectual and developmental disabilities (IDD) are at high risk for unmet health care needs and face barriers to equitable care, yet few health professions students receive adequate training to meet these needs. OBJECTIVES: An interactive panel discussion with Special Olympics Pennsylvania (SOPA) athletes and staff was planned and implemented so that health professions students/trainees would gain knowledge of IDD, health barriers, SOPA resources, and volunteer opportunities. METHODS: Panelists included two SOPA athletes and their mentors; questions solicited responses about personal health care experiences (Fall 2019). Attendees completed a mixed-methods post-event survey capturing event satisfaction, reflections, and interest in learning more about patients with IDD. RESULTS: Sixty individuals attended, and 43 (72%) completed post-event evaluation. Attendees reported high satisfaction (88%), desire for future trainings (100%), and interest in learning about communicating (88%), providing care (88%), and addressing IDD health barriers (91%). CONCLUSIONS: Collaborative community panels could be effective in engaging health care students in discussion about caring for patients with IDD.


Asunto(s)
Personas con Discapacidad , Humanos , Femenino , Masculino , Pennsylvania , Discapacidades del Desarrollo/terapia , Investigación Participativa Basada en la Comunidad , Discapacidad Intelectual , Adulto
11.
Brain Commun ; 6(4): fcae183, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39021510

RESUMEN

Predominant limbic degeneration has been associated with various underlying aetiologies and an older age, predominant impairment of episodic memory and slow clinical progression. However, the neurological syndrome associated with predominant limbic degeneration is not defined. This endeavour is critical to distinguish such a syndrome from those originating from neocortical degeneration, which may differ in underlying aetiology, disease course and therapeutic needs. We propose a set of clinical criteria for a limbic-predominant amnestic neurodegenerative syndrome that is highly associated with limbic-predominant age-related TDP-43 encephalopathy but also other pathologic entities. The criteria incorporate core, standard and advanced features, including older age at evaluation, mild clinical syndrome, disproportionate hippocampal atrophy, impaired semantic memory, limbic hypometabolism, absence of neocortical degeneration and low likelihood of neocortical tau, with degrees of certainty (highest, high, moderate and low). We operationalized this set of criteria using clinical, imaging and biomarker data to validate its associations with clinical and pathologic outcomes. We screened autopsied patients from Mayo Clinic and Alzheimer's Disease Neuroimaging Initiative cohorts and applied the criteria to those with an antemortem predominant amnestic syndrome (Mayo, n = 165; Alzheimer's Disease Neuroimaging Initiative, n = 53) and who had Alzheimer's disease neuropathological change, limbic-predominant age-related TDP-43 encephalopathy or both pathologies at autopsy. These neuropathology-defined groups accounted for 35, 37 and 4% of cases in the Mayo cohort, respectively, and 30, 22 and 9% of cases in the Alzheimer's Disease Neuroimaging Initiative cohort, respectively. The criteria effectively categorized these cases, with Alzheimer's disease having the lowest likelihoods, limbic-predominant age-related TDP-43 encephalopathy patients having the highest likelihoods and patients with both pathologies having intermediate likelihoods. A logistic regression using the criteria features as predictors of TDP-43 achieved a balanced accuracy of 74.6% in the Mayo cohort, and out-of-sample predictions in an external cohort achieved a balanced accuracy of 73.3%. Patients with high likelihoods had a milder and slower clinical course and more severe temporo-limbic degeneration compared to those with low likelihoods. Stratifying patients with both Alzheimer's disease neuropathological change and limbic-predominant age-related TDP-43 encephalopathy from the Mayo cohort according to their likelihoods revealed that those with higher likelihoods had more temporo-limbic degeneration and a slower rate of decline and those with lower likelihoods had more lateral temporo-parietal degeneration and a faster rate of decline. The implementation of criteria for a limbic-predominant amnestic neurodegenerative syndrome has implications to disambiguate the different aetiologies of progressive amnestic presentations in older age and guide diagnosis, prognosis, treatment and clinical trials.

13.
J Nurses Prof Dev ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39042849

RESUMEN

An integrated health system including 12 hospitals, an expansive network of ambulatory settings, and health insurance plans began a systematic review of the existing nursing professional practice model (PPM) created in 2007 to assess current relevancy. The goal was to determine PPM concepts and imagery that represent present-day nursing workforce. This article shares how a formal review of literature, utilization of focus groups, and system-wide shared decision-making influenced creation and evaluation of a revised PPM.

14.
J Sch Nurs ; : 10598405241265706, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042884

RESUMEN

In 2021, the National Association of School Nurses published an updated position statement affirming the unique position of school nurses to support the health and well-being of lesbian, gay, bisexual, transgender, and queer/questioning (LGBTQ+) students who are faced with a variety of health disparities rooted in experiences of stigma, discrimination, and bias. The 5-year cluster randomized controlled trial "Reducing LGBTQ+ Adolescent Suicide" leveraged school nurses as leaders to facilitate the uptake of six evidence-informed, LGBTQ-supportive practices in New Mexico high schools. We analyzed 5 years of interview data from 24 school nurses in 13 intervention schools to examine what factors impacted their ability to serve as an effective leader for this initiative. Several factors including job characteristics, leadership and organizational skills, relationships and reputation, and personal commitments emerged from analysis. Contextual factors, such as working in urban or rural school, and the size of the school also influenced nurses' leadership.

15.
Neuroimage Clin ; 43: 103639, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38991435

RESUMEN

Primary progressive aphasia (PPA) variants present with distinct disruptions in speech-language functions with little known about the interplay between affected and spared regions within the speech-language network and their interaction with other functional networks. The Neurodegenerative Research Group, Mayo Clinic, recruited 123 patients with PPA (55 logopenic (lvPPA), 44 non-fluent (nfvPPA) and 24 semantic (svPPA)) who were matched to 60 healthy controls. We investigated functional connectivity disruptions between regions within the left-speech-language network (Broca, Wernicke, anterior middle temporal gyrus (aMTG), supplementary motor area (SMA), planum temporale (PT) and parietal operculum (PO)), and disruptions to other networks (visual association, dorsal-attention, frontoparietal and default mode networks (DMN)). Within the speech-language network, multivariate linear regression models showed reduced aMTG-Broca connectivity in all variants, with lvPPA and nfvPPA findings remaining significant after Bonferroni correction. Additional loss in Wernicke-Broca connectivity in nfvPPA, Wernicke-PT connectivity in lvPPA and greater aMTG-PT connectivity in svPPA were also noted. Between-network connectivity findings in all variants showed reduced aMTG-DMN and increased aMTG-dorsal-attention connectivity, with additional disruptions between aMTG-visual association in both lvPPA and svPPA, aMTG-frontoparietal in lvPPA, and Wernicke-DMN breakdown in svPPA. These findings suggest that aMTG connectivity breakdown is a shared feature in all PPA variants, with lvPPA showing more extensive connectivity disruptions with other networks.

16.
Neurosurgery ; 95(2): 480-486, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39008546

RESUMEN

BACKGROUND AND OBJECTIVES: Health care providers' exposure to global surgical disparities is limited in current nursing and/or medical school curricula. For instance, global health is often associated with infectious diseases or maternal health without acknowledging the growing need for surgical care in low- and middle-income countries (LMICs). We propose an international virtual hackathon based on neurosurgical patient cases in under-resourced settings as an educational tool to bring awareness to global surgical disparities and develop relationships among trainees in different countries. METHODS: Participants were recruited through email listservs, a social media campaign, and prize offerings. A 3-day virtual hackathon event was administered, which included workshops, mentorship, keynote panels, and pitch presentations to judges. Participants were presented with real patient cases and directed to solve a barrier to their care. Surveys assessed participants' backgrounds and event experience. The hackathon was executed through Zoom at Harvard Innovation Lab in Boston, MA, on March 25 to 27, 2022. Participants included medical students, with additional participants from business, engineering, or current health care workers. RESULTS: Three hundred seven applications were submitted for 100 spots. Participants included medical students, physicians, nurses, engineers, entrepreneurs, and undergraduates representing 25 countries and 82 cities. Fifty-one participants previously met a neurosurgeon, while 39 previously met a global health expert, with no difference between LMIC and high-income countries' respondents. Teams spent an average of 2.75 hours working with mentors, and 88% of postevent respondents said the event was "very" or "extremely conducive" to networking. Projects fell into 4 categories: access, language barriers, education and training, and resources. The winning team, which was interdisciplinary and international, developed an application that analyzes patient anatomy while performing physical therapy to facilitate remote care and clinical decision-making. CONCLUSION: An international virtual hackathon can be an educational tool to increase innovative ideas to address surgical disparities in LMICs and establish early collaborative relationships with medical trainees from different countries.


Asunto(s)
Salud Global , Neurocirugia , Humanos , Neurocirugia/educación , Países en Desarrollo , Procedimientos Neuroquirúrgicos/educación , Neurocirujanos/educación
17.
Am J Epidemiol ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013792

RESUMEN

The objectives of this study were to examine the total effect of grandmaternal [G0] pre-pregnancy body mass index (BMI) on infant [G2] birthweight z-score and to quantify the mediation role of maternal [G1] pre-pregnancy BMI. Data were extracted from the Nova Scotia 3G Multigenerational Cohort. The association between G0 pre-pregnancy BMI and G2 birthweight z-score and the mediated effect by G1 pre-pregnancy BMI were estimated using g-computation with adjustment for confounders identified using a directed acyclic graph and accounting for intermediate confounding. 20822 G1-G2 dyads from 18450 G0 were included. Relative to G0 normal weight, G0 underweight decreased mean G2 birthweight z-score (-0.11, 95% confidence interval (CI) -0.20, -0.030), while G0 overweight and obesity increased mean G2 birthweight z-score (0.091 [95% CI 0.034, 0.15] and 0.22 [95% CI 0.11, 0.33]). G1 pre-pregnancy BMI partly mediated the association, with the largest effect size observed for G0 obesity (0.11, 95% CI 0.080, 0.14). Estimates of the direct effect were close to the null. In conclusion, grandmaternal pre-pregnancy BMI was associated with infant birthweight z-score. Maternal pre-pregnancy BMI partly mediated the association, suggesting that factors related to BMI may play an important role in the transmission of weight across the maternal line.

18.
J Alzheimers Dis ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38995784

RESUMEN

Background: Conventional normative samples include individuals with undetected Alzheimer's disease neuropathology, lowering test sensitivity for cognitive impairment. Objective: We developed Mayo Normative Studies (MNS) norms limited to individuals without elevated amyloid or neurodegeneration (A-N-) for Rey's Auditory Verbal Learning Test (AVLT). We compared these MNS A-N- norms in female, male, and total samples to conventional MNS norms with varying levels of demographic adjustments. Methods: The A-N- sample included 1,059 Mayo Clinic Study of Aging cognitively unimpaired (CU) participants living in Olmsted County, MN, who are predominantly non-Hispanic White. Using a regression-based approach correcting for age, sex, and education, we derived fully-adjusted T-score formulas for AVLT variables. We validated these A-N- norms in two independent samples of CU (n = 261) and mild cognitive impairment (MCI)/dementia participants (n = 392) > 55 years of age. Results: Variability associated with age decreased by almost half in the A-N- norm sample relative to the conventional norm sample. Fully-adjusted MNS A-N- norms showed approximately 7- 9% higher sensitivity to MCI/dementia compared to fully-adjusted MNS conventional norms for trials 1- 5 total and sum of trials. Among women, sensitivity to MCI/dementia increased with each normative data refinement. In contrast, age-adjusted conventional MNS norms showed greatest sensitivity to MCI/dementia in men. Conclusions: A-N- norms show some benefits over conventional normative approaches to MCI/dementia sensitivity, especially for women. We recommend using these MNS A-N- norms alongside MNS conventional norms. Future work is needed to determine if normative samples that are not well characterized clinically show greater benefit from biomarker-refined approaches.

19.
bioRxiv ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39005276

RESUMEN

Early-life immune exposures can profoundly impact lifelong health. However, functional mechanisms underlying fetal immune development remain incomplete. Erythrocytes are not typically considered active immune mediators, primarily because erythroid precursors discard their organelles as they mature, thus losing the ability to alter gene expression in response to stimuli. Erythroid progenitors and precursors circulate in human fetuses and neonates. Although there is limited evidence that erythroid precursors are immunomodulatory, our understanding of the underlying mechanisms remains inadequate. To define the immunobiological role of fetal and perinatal erythroid progenitors and precursors, we analyzed single cell RNA-sequencing data and found that transcriptomics support erythroid progenitors as putative immune mediators. Unexpectedly, we discovered that human erythroid progenitors constitutively express Major Histocompatibility Complex (MHC) class II antigen processing and presentation machinery, which are hallmarks of specialized antigen presenting immune cells. Furthermore, we demonstrate that erythroid progenitors internalize and cleave foreign proteins into peptide antigens. Unlike conventional antigen presenting cells, erythroid progenitors express atypical costimulatory molecules and immunoregulatory cytokines that direct the development of regulatory T cells, which are critical for establishing maternal-fetal tolerance. Expression of MHC II in definitive erythroid progenitors begins during the second trimester, coinciding with the appearance of mature T cells in the fetus, and is absent in primitive progenitors. Lastly, we demonstrate physical and molecular interaction potential of erythroid progenitors and T cells in the fetal liver. Our findings shed light on a unique orchestrator of fetal immunity and provide insight into the mechanisms by which erythroid cells contribute to host defense.

20.
medRxiv ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-39006432

RESUMEN

Defects in mitochondrial dynamics are a common cause of Charcot-Marie-Tooth disease (CMT), while primary deficiencies in the mitochondrial respiratory chain (MRC) are rare and atypical for this etiology. This study aims to report COX18 as a novel CMT-causing gene. This gene encodes an assembly factor of mitochondrial Complex IV (CIV) that translocates the C-terminal tail of MTCO2 across the mitochondrial inner membrane. Exome sequencing was performed in four affected individuals. The patients and available family members underwent thorough neurological and electrophysiological assessment. The impact of one of the identified variants on splicing, protein levels, and mitochondrial bioenergetics was investigated in patient-derived lymphoblasts. The functionality of the mutant protein was assessed using a Proteinase K protection assay and immunoblotting. Neuronal relevance of COX18 was assessed in a Drosophila melanogaster knockdown model. Exome sequencing coupled with homozygosity mapping revealed a homozygous splice variant c.435-6A>G in COX18 in two siblings with early-onset progressive axonal sensory-motor peripheral neuropathy. By querying external databases, we identified two additional families with rare deleterious biallelic variants in COX18 . All affected individuals presented with axonal CMT and some patients also exhibited central nervous system symptoms, such as dystonia and spasticity. Functional characterization of the c.435-6A>G variant demonstrated that it leads to the expression of an alternative transcript that lacks exon 2, resulting in a stable but defective COX18 isoform. The mutant protein impairs CIV assembly and activity, leading to a reduction in mitochondrial membrane potential. Downregulation of the COX18 homolog in Drosophila melanogaster displayed signs of neurodegeneration, including locomotor deficit and progressive axonal degeneration of sensory neurons. Our study presents genetic and functional evidence that supports COX18 as a newly identified gene candidate for autosomal recessive axonal CMT with or without central nervous system involvement. These findings emphasize the significance of peripheral neuropathy within the spectrum of primary mitochondrial disorders and the role of mitochondrial CIV in the development of CMT. Our research has important implications for the diagnostic workup of CMT patients.

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