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1.
Cell ; 163(4): 934-46, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26544940

RESUMEN

Chemical cross-linking and DNA sequencing have revealed regions of intra-chromosomal interaction, referred to as topologically associating domains (TADs), interspersed with regions of little or no interaction, in interphase nuclei. We find that TADs and the regions between them correspond with the bands and interbands of polytene chromosomes of Drosophila. We further establish the conservation of TADs between polytene and diploid cells of Drosophila. From direct measurements on light micrographs of polytene chromosomes, we then deduce the states of chromatin folding in the diploid cell nucleus. Two states of folding, fully extended fibers containing regulatory regions and promoters, and fibers condensed up to 10-fold containing coding regions of active genes, constitute the euchromatin of the nuclear interior. Chromatin fibers condensed up to 30-fold, containing coding regions of inactive genes, represent the heterochromatin of the nuclear periphery. A convergence of molecular analysis with direct observation thus reveals the architecture of interphase chromosomes.


Asunto(s)
Drosophila melanogaster/genética , Cromosomas Politénicos/química , Animales , Núcleo Celular/química , Núcleo Celular/genética , Puffs Cromosómicos , Diploidia , Drosophila melanogaster/química , Drosophila melanogaster/citología , Drosophila melanogaster/crecimiento & desarrollo , Técnicas Genéticas , Larva/química
2.
Mol Cell ; 78(1): 112-126.e12, 2020 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-32243828

RESUMEN

Delineating how chromosomes fold at length scales beyond one megabase remains obscure relative to smaller-scale folding into TADs, loops, and nucleosomes. We find that rather than simply unfolding chromatin, histone hyperacetylation results in interactions between distant genomic loci separated by tens to hundreds of megabases, even in the absence of transcription. These hyperacetylated "megadomains" are formed by the BRD4-NUT fusion oncoprotein, interact both within and between chromosomes, and form a specific nuclear subcompartment that has elevated gene activity with respect to other subcompartments. Pharmacological degradation of BRD4-NUT results in collapse of megadomains and attenuation of the interactions between them. In contrast, these interactions persist and contacts between newly acetylated regions are formed after inhibiting RNA polymerase II initiation. Our structure-function approach thus reveals that broad chromatin domains of identical biochemical composition, independent of transcription, form nuclear subcompartments, and also indicates the potential of altering chromosome structure for treating human disease.


Asunto(s)
Núcleo Celular/genética , Cromatina/metabolismo , Cromosomas de los Mamíferos/química , Acetilación , Línea Celular , Núcleo Celular/metabolismo , Cromatina/química , Cromatina/efectos de los fármacos , Cromosomas de los Mamíferos/metabolismo , Expresión Génica , Humanos , Masculino , Proteínas Nucleares/metabolismo , Proteínas de Fusión Oncogénica/metabolismo
3.
Hum Mol Genet ; 33(8): 709-723, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38272461

RESUMEN

Biallelic mutations in Protein O-mannosyltransferase 1 (POMT1) are among the most common causes of a severe group of congenital muscular dystrophies (CMDs) known as dystroglycanopathies. POMT1 is a glycosyltransferase responsible for the attachment of a functional glycan mediating interactions between the transmembrane glycoprotein dystroglycan and its binding partners in the extracellular matrix (ECM). Disruptions in these cell-ECM interactions lead to multiple developmental defects causing brain and eye malformations in addition to CMD. Removing Pomt1 in the mouse leads to early embryonic death due to the essential role of dystroglycan during placental formation in rodents. Here, we characterized and validated a model of pomt1 loss of function in the zebrafish showing that developmental defects found in individuals affected by dystroglycanopathies can be recapitulated in the fish. We also discovered that pomt1 mRNA provided by the mother in the oocyte supports dystroglycan glycosylation during the first few weeks of development. Muscle disease, retinal synapse formation deficits, and axon guidance defects can only be uncovered during the first week post fertilization by generating knock-out embryos from knock-out mothers. Conversely, maternal pomt1 from heterozygous mothers was sufficient to sustain muscle, eye, and brain development only leading to loss of photoreceptor synapses at 30 days post fertilization. Our findings show that it is important to define the contribution of maternal mRNA while developing zebrafish models of dystroglycanopathies and that offspring generated from heterozygous and knock-out mothers can be used to differentiate the role of dystroglycan glycosylation in tissue formation and maintenance.


Asunto(s)
Distroglicanos , Pez Cebra , Animales , Distroglicanos/genética , Distroglicanos/metabolismo , Glicosilación , Fenotipo , Pez Cebra/genética , Pez Cebra/metabolismo
4.
Brief Bioinform ; 25(Supplement_1)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39041915

RESUMEN

This manuscript describes the development of a resources module that is part of a learning platform named 'NIGMS Sandbox for Cloud-based Learning' https://github.com/NIGMS/NIGMS-Sandbox. The overall genesis of the Sandbox is described in the editorial NIGMS Sandbox at the beginning of this Supplement. This module delivers learning materials on implementing deep learning algorithms for biomedical image data in an interactive format that uses appropriate cloud resources for data access and analyses. Biomedical-related datasets are widely used in both research and clinical settings, but the ability for professionally trained clinicians and researchers to interpret datasets becomes difficult as the size and breadth of these datasets increases. Artificial intelligence, and specifically deep learning neural networks, have recently become an important tool in novel biomedical research. However, use is limited due to their computational requirements and confusion regarding different neural network architectures. The goal of this learning module is to introduce types of deep learning neural networks and cover practices that are commonly used in biomedical research. This module is subdivided into four submodules that cover classification, augmentation, segmentation and regression. Each complementary submodule was written on the Google Cloud Platform and contains detailed code and explanations, as well as quizzes and challenges to facilitate user training. Overall, the goal of this learning module is to enable users to identify and integrate the correct type of neural network with their data while highlighting the ease-of-use of cloud computing for implementing neural networks. This manuscript describes the development of a resource module that is part of a learning platform named ``NIGMS Sandbox for Cloud-based Learning'' https://github.com/NIGMS/NIGMS-Sandbox. The overall genesis of the Sandbox is described in the editorial NIGMS Sandbox [1] at the beginning of this Supplement. This module delivers learning materials on the analysis of bulk and single-cell ATAC-seq data in an interactive format that uses appropriate cloud resources for data access and analyses.


Asunto(s)
Aprendizaje Profundo , Redes Neurales de la Computación , Humanos , Investigación Biomédica , Algoritmos , Nube Computacional
5.
EMBO J ; 40(24): e108307, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34786730

RESUMEN

Histone chaperones modulate the stability of histones beginning from histone synthesis, through incorporation into DNA, and during recycling during transcription and replication. Following histone removal from DNA, chaperones regulate histone storage and degradation. Here, we demonstrate that UBR7 is a histone H3.1 chaperone that modulates the supply of pre-existing post-nucleosomal histone complexes. We demonstrate that UBR7 binds to post-nucleosomal H3K4me3 and H3K9me3 histones via its UBR box and PHD. UBR7 binds to the non-nucleosomal histone chaperone NASP. In the absence of UBR7, the pool of NASP-bound post-nucleosomal histones accumulate and chromatin is depleted of H3K4me3-modified histones. We propose that the interaction of UBR7 with NASP and histones opposes the histone storage functions of NASP and that UBR7 promotes reincorporation of post-nucleosomal H3 complexes.


Asunto(s)
Autoantígenos/metabolismo , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Línea Celular , Células HEK293 , Células HeLa , Código de Histonas , Histonas/química , Humanos , Nucleosomas/metabolismo , Dominios Proteicos
6.
Brain ; 147(9): 3216-3233, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38815055

RESUMEN

Intraventricular haemorrhage is a common complication of premature birth. Survivors are often left with cerebral palsy, intellectual disability and/or hydrocephalus. Animal models suggest that brain tissue shrinkage, with subsequent vascular stretch and tear, is an important step in the pathophysiology, but the cause of this shrinkage is unknown. Clinical risk factors for intraventricular haemorrhage are biomarkers of hypoxic-ischaemic stress, which causes mature neurons to swell. However, immature neuronal volume might shift in the opposite direction in these conditions. This is because immature neurons express the chloride, salt and water transporter NKCC1, which subserves regulatory volume increases in non-neural cells, whereas mature neurons express KCC2, which subserves regulatory volume decreases. When hypoxic-ischaemic conditions reduce active ion transport and increase the cytoplasmic membrane permeability, the effects of these transporters are diminished. Consequentially, mature neurons swell (cytotoxic oedema), whereas immature neurons might shrink. After hypoxic-ischaemic stress, in vivo and in vitro multi-photon imaging of perinatal transgenic mice demonstrated shrinkage of viable immature neurons, bulk tissue shrinkage and blood vessel displacement. Neuronal shrinkage was correlated with age-dependent membrane salt and water transporter expression using immunohistochemistry. Shrinkage of immature neurons was prevented by prior genetic or pharmacological inhibition of NKCC1 transport. These findings open new avenues of investigation for the detection of acute brain injury by neuroimaging, in addition to prevention of neuronal shrinkage and the ensuing intraventricular haemorrhage, in premature infants.


Asunto(s)
Recien Nacido Prematuro , Neuronas , Miembro 2 de la Familia de Transportadores de Soluto 12 , Animales , Humanos , Recién Nacido , Ratones , Hemorragia Cerebral Intraventricular/metabolismo , Cotransportadores de K Cl , Neuronas/metabolismo , Simportadores de Cloruro de Sodio-Potasio/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Simportadores/metabolismo
7.
Clin Infect Dis ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39172994

RESUMEN

BACKGROUND: Pneumonia is common in adults hospitalized with laboratory-confirmed influenza, but the association between timeliness of influenza antiviral treatment and severe clinical outcomes in patients with influenza-associated pneumonia is not well characterized. METHODS: We included adults aged ≥18 years hospitalized with laboratory-confirmed influenza and a discharge diagnosis of pneumonia over 7 influenza seasons (2012-2019) sampled from a multi-state population-based surveillance network. We evaluated 3 treatment groups based on timing of influenza antiviral initiation relative to admission date (day 0, day 1, days 2-5). Baseline characteristics and clinical outcomes were compared across groups using unweighted counts and weighted percentages accounting for the complex survey design. Logistic regression models were generated to evaluate the association between delayed treatment and 30-day all-cause mortality. RESULTS: 26,233 adults were sampled in the analysis. Median age was 71 years and most (92.2%) had ≥1 non-immunocompromising condition. Overall, 60.9% started antiviral treatment on day 0, 29.5% on day 1, and 9.7% on days 2-5 (median 2 days). Baseline characteristics were similar across groups. Thirty-day mortality occurred in 7.5%, 8.5%, and 10.2% of patients who started treatment on day 0, day 1, and days 2-5, respectively. Compared to those treated on day 0, adjusted OR for death was 1.14 (95%CI: 1.01-1.27) in those starting treatment on day 1 and 1.40 (95%CI: 1.17-1.66) in those starting on days 2-5. DISCUSSION: Delayed initiation of antiviral treatment in patients hospitalized with influenza-associated pneumonia was associated with higher risk of death, highlighting the importance of timely initiation of antiviral treatment at admission.

8.
Neurogenetics ; 25(2): 93-102, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38296890

RESUMEN

Congenital muscular dystrophies (CMDs) are a group of rare muscle disorders characterized by early onset hypotonia and motor developmental delay associated with brain malformations with or without eye anomalies in the most severe cases. In this study, we aimed to uncover the genetic basis of severe CMD in Egypt and to determine the efficacy of whole exome sequencing (WES)-based genetic diagnosis in this population. We recruited twelve individuals from eleven families with a clinical diagnosis of CMD with brain malformations that fell into two groups: seven patients with suspected dystroglycanopathy and five patients with suspected merosin-deficient CMD. WES was analyzed by variant filtering using multiple approaches including splicing and copy number variant (CNV) analysis. We identified likely pathogenic variants in FKRP in two cases and variants in POMT1, POMK, and B3GALNT2 in three individuals. All individuals with merosin-deficient CMD had truncating variants in LAMA2. Further analysis in one of the two unsolved cases showed a homozygous protein-truncating variant in Feline Leukemia Virus subgroup C Receptor 1 (FLVCR1). FLVCR1 loss of function has never been previously reported. Yet, loss of function of its paralog, FLVCR2, causes lethal hydranencephaly-hydrocephaly syndrome (Fowler Syndrome) which should be considered in the differential diagnosis for dystroglycanopathy. Overall, we reached a diagnostic rate of 86% (6/7) for dystroglycanopathies and 100% (5/5) for merosinopathy. In conclusion, our results provide further evidence that WES is an important diagnostic method in CMD in developing countries to improve the diagnostic rate, management plan, and genetic counseling for these disorders.


Asunto(s)
Encéfalo , Secuenciación del Exoma , Distrofias Musculares , N-Acetilglucosaminiltransferasas , Humanos , Masculino , Egipto , Femenino , Distrofias Musculares/genética , Distrofias Musculares/diagnóstico , Preescolar , Encéfalo/anomalías , Encéfalo/patología , Niño , Lactante , Laminina/genética , Receptores Virales/genética , Manosiltransferasas/genética , Linaje , Pentosiltransferasa/genética , Variaciones en el Número de Copia de ADN , Mutación , Adolescente , Malformaciones del Sistema Nervioso/genética
9.
Neurogenetics ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066872

RESUMEN

ATPase, class 1, type 8 A, member 2 (ATP8A2) is a P4-ATPase with a critical role in phospholipid translocation across the plasma membrane. Pathogenic variants in ATP8A2 are known to cause cerebellar ataxia, impaired intellectual development, and disequilibrium syndrome 4 (CAMRQ4) which is often associated with encephalopathy, global developmental delay, and severe motor deficits. Here, we present a family with two siblings born from a consanguineous, first-cousin union from Sudan presenting with global developmental delay, intellectual disability, spasticity, ataxia, nystagmus, and thin corpus callosum. Whole exome sequencing revealed a homozygous missense variant in the nucleotide binding domain of ATP8A2 (p.Leu538Pro) that results in near complete loss of protein expression. This is in line with other missense variants in the same domain leading to protein misfolding and loss of ATPase function. In addition, by performing diffusion-weighted imaging, we identified bilateral hyperintensities in the posterior limbs of the internal capsule suggesting possible microstructural changes in axon tracts that had not been appreciated before and could contribute to the sensorimotor deficits in these individuals.

10.
Am J Epidemiol ; 193(10): 1384-1391, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-38844537

RESUMEN

Human-induced climate change has led to more frequent and severe flooding around the globe. We examined the association between flood risk and the prevalence of coronary heart disease, high blood pressure, asthma, and poor mental health in the United States, while taking into account different levels of social vulnerability. We aggregated flood risk variables from First Street Foundation data by census tract and used principal component analysis to derive a set of 5 interpretable flood risk factors. The dependent variables were census-tract level disease prevalences generated by the Centers for Disease Control and Prevention. Bayesian spatial conditional autoregressive models were fit on these data to quantify the relationship between flood risk and health outcomes under different stratifications of social vulnerability. We show that 3 flood risk principal components had small but significant associations with each of the health outcomes across the different stratifications of social vulnerability. Our analysis gives, to our knowledge, the first United States-wide estimates of the associated effects of flood risk on specific health outcomes. We also show that social vulnerability is an important moderator of the relationship between flood risk and health outcomes. Our approach can be extended to other ecological studies that examine the health impacts of climate hazards. This article is part of a Special Collection on Environmental Epidemiology.


Asunto(s)
Asma , Teorema de Bayes , Censos , Inundaciones , Humanos , Inundaciones/estadística & datos numéricos , Estados Unidos/epidemiología , Asma/epidemiología , Factores de Riesgo , Hipertensión/epidemiología , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/etiología , Vulnerabilidad Social , Cambio Climático , Prevalencia , Análisis de Componente Principal , Salud Mental/estadística & datos numéricos
11.
Nat Mater ; 22(9): 1144-1151, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37580369

RESUMEN

Ferroelectricity in binary oxides including hafnia and zirconia has riveted the attention of the scientific community due to the highly unconventional physical mechanisms and the potential for the integration of these materials into semiconductor workflows. Over the last decade, it has been argued that behaviours such as wake-up phenomena and an extreme sensitivity to electrode and processing conditions suggest that ferroelectricity in these materials is strongly influenced by other factors, including electrochemical boundary conditions and strain. Here we argue that the properties of these materials emerge due to the interplay between the bulk competition between ferroelectric and structural instabilities, similar to that in classical antiferroelectrics, coupled with non-local screening mediated by the finite density of states at surfaces and internal interfaces. Via the decoupling of electrochemical and electrostatic controls, realized via environmental and ultra-high vacuum piezoresponse force microscopy, we show that these materials demonstrate a rich spectrum of ferroic behaviours including partial-pressure-induced and temperature-induced transitions between ferroelectric and antiferroelectric behaviours. These behaviours are consistent with an antiferroionic model and suggest strategies for hafnia-based device optimization.

12.
Genet Med ; : 101273, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39306721

RESUMEN

PURPOSE: FLVCR1 encodes a solute carrier (SLC) protein implicated in heme, choline, and ethanolamine transport. While Flvcr1-/- mice exhibit skeletal malformations and defective erythropoiesis reminiscent of Diamond-Blackfan anemia (DBA), biallelic FLVCR1 variants in humans have previously only been linked to childhood or adult-onset ataxia, sensory neuropathy, and retinitis pigmentosa. METHODS: We identified individuals with undiagnosed neurodevelopmental disorders and biallelic FLVCR1 variants through international data sharing and characterized the functional consequences of their FLVCR1 variants. RESULTS: We ascertained 30 patients from 23 unrelated families with biallelic FLVCR1 variants and characterized a novel FLVCR1-related phenotype: severe developmental disorders with profound developmental delay, microcephaly (Z-score -2.5 to -10.5), brain malformations, epilepsy, spasticity, and premature death. Brain malformations ranged from mild brain volume reduction to hydranencephaly. Severely affected patients share traits including macrocytic anemia and skeletal malformations with Flvcr1-/- mice and DBA. FLVCR1 variants significantly reduce choline and ethanolamine transport and/or disrupt mRNA splicing. CONCLUSION: These data demonstrate a broad FLVCR1-related phenotypic spectrum ranging from severe multiorgan developmental disorders resembling DBA to adult-onset neurodegeneration. Our study expands our understanding of Mendelian choline and ethanolamine disorders and illustrates the importance of anticipating a wide phenotypic spectrum for known disease genes and incorporating model organism data into genome analysis to maximize genetic testing yield.

13.
Annu Rev Biomed Eng ; 25: 413-443, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37104650

RESUMEN

Over the last half century, the autofluorescence of the metabolic cofactors NADH (reduced nicotinamide adenine dinucleotide) and FAD (flavin adenine dinucleotide) has been quantified in a variety of cell types and disease states. With the spread of nonlinear optical microscopy techniques in biomedical research, NADH and FAD imaging has offered an attractive solution to noninvasively monitor cell and tissue status and elucidate dynamic changes in cell or tissue metabolism. Various tools and methods to measure the temporal, spectral, and spatial properties of NADH and FAD autofluorescence have been developed. Specifically, an optical redox ratio of cofactor fluorescence intensities and NADH fluorescence lifetime parameters have been used in numerous applications, but significant work remains to mature this technology for understanding dynamic changes in metabolism. This article describes the current understanding of our optical sensitivity to different metabolic pathways and highlights current challenges in the field. Recent progress in addressing these challenges and acquiring more quantitative information in faster and more metabolically relevant formats is also discussed.


Asunto(s)
Flavina-Adenina Dinucleótido , NAD , Humanos , NAD/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Oxidación-Reducción , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Imagen Óptica
14.
J Urol ; : 101097JU0000000000004224, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39186830

RESUMEN

PURPOSE: Epididymal cyst lesions (ECLs) include both spermatoceles and epididymal cysts and are often incidentally found on physical exam or scrotal US (SUS). We aimed to determine the association of ECLs and semen parameters among men presenting for fertility evaluation. MATERIALS AND METHODS: We reviewed men at our institution who had at least 1 semen analysis and SUS available for review between 2002 and 2022. SUS data included testicular measurements, presence or absence of subclinical varicocele, and size and laterality of ECL, if present. Demographic and clinical information including serum testosterone and follicle-stimulating hormone and semen parameters were compared between men with and without ECLs. RESULTS: Among 861 men, 164 (19%) had unilateral right ECL (median 4 mm, interquartile range 3-8 mm), 189 (22%) had unilateral left ECL (median 4 mm, interquartile range 3-9 mm), and 113 (13%) had bilateral ECL. Patients with ECLs were significantly older than men without ECLs at the time of evaluation but had no statistically significant difference in semen volume, sperm concentration, sperm motility, sperm morphology, total motile sperm count, or serum hormonal values. Analysis of men with unilateral and bilateral ECLs showed that ECL size and laterality did not significantly correlate with any semen parameter evaluated. CONCLUSIONS: We found no association between ECLs and semen parameters. Patients should be counseled toward conservative management with observation for asymptomatic ECLs in the setting of fertility evaluation.

15.
Cerebellum ; 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38165577

RESUMEN

Autism spectrum disorders (ASD) involve brain wide abnormalities that contribute to a constellation of symptoms including behavioral inflexibility, cognitive dysfunction, learning impairments, altered social interactions, and perceptive time difficulties. Although a single genetic variation does not cause ASD, genetic variations such as one involving a non-canonical Wnt signaling gene, Prickle2, has been found in individuals with ASD. Previous work looking into phenotypes of Prickle2 knock-out (Prickle2-/-) and heterozygous mice (Prickle2-/+) suggest patterns of behavior similar to individuals with ASD including altered social interaction and behavioral inflexibility. Growing evidence implicates the cerebellum in ASD. As Prickle2 is expressed in the cerebellum, this animal model presents a unique opportunity to investigate the cerebellar contribution to autism-like phenotypes. Here, we explore cerebellar structural and physiological abnormalities in animals with Prickle2 knockdown using immunohistochemistry, whole-cell patch clamp electrophysiology, and several cerebellar-associated motor and timing tasks, including interval timing and eyeblink conditioning. Histologically, Prickle2-/- mice have significantly more empty spaces or gaps between Purkinje cells in the posterior lobules and a decreased propensity for Purkinje cells to fire action potentials. These structural cerebellar abnormalities did not impair cerebellar-associated behaviors as eyeblink conditioning and interval timing remained intact. Therefore, although Prickle-/- mice show classic phenotypes of ASD, they do not recapitulate the involvement of the adult cerebellum and may not represent the pathophysiological heterogeneity of the disorder.

16.
Epilepsia ; 65(7): 2165-2178, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38752861

RESUMEN

OBJECTIVE: The increased amplitude of ictal activity is a common feature of epileptic seizures, but the determinants of this amplitude have not been identified. Clinically, ictal amplitudes are measured electrographically (using, e.g., electroencephalography, electrocorticography, and depth electrodes), but these methods do not enable the assessment of the activity of individual neurons. Population signal may increase from three potential sources: (1) increased synchrony (i.e., more coactive neurons); (2) altered active state, from bursts of action potentials and/or paroxysmal depolarizing shifts in membrane potential; and (3) altered subthreshold state, which includes all lower levels of activity. Here, we quantify the fraction of ictal signal from each source. METHODS: To identify the cellular determinants of the ictal signal, we measured single cell and population electrical activity and neuronal calcium levels via optical imaging of the genetically encoded calcium indicator (GECI) GCaMP. Spontaneous seizure activity was assessed with microendoscopy in an APP/PS1 mouse with focal cortical injury and via widefield imaging in the organotypic hippocampal slice cultures (OHSCs) model of posttraumatic epilepsy. Single cell calcium signals were linked to a range of electrical activities by performing simultaneous GECI-based calcium imaging and whole-cell patch-clamp recordings in spontaneously seizing OHSCs. Neuronal resolution calcium imaging of spontaneous seizures was then used to quantify the cellular contributions to population-level ictal signal. RESULTS: The seizure onset signal was primarily driven by increased subthreshold activity, consistent with either barrages of excitatory postsynaptic potentials or sustained membrane depolarization. Unsurprisingly, more neurons entered the active state as seizure activity progressed. However, the increasing fraction of active cells was primarily driven by synchronous reactivation and not from continued recruitment of new populations of neurons into the seizure. SIGNIFICANCE: This work provides a critical link between single neuron activity and population measures of seizure activity.


Asunto(s)
Hipocampo , Neuronas , Animales , Ratones , Neuronas/fisiología , Hipocampo/fisiopatología , Potenciales de Acción/fisiología , Ratones Transgénicos , Ratones Endogámicos C57BL , Electroencefalografía/métodos , Convulsiones/fisiopatología , Epilepsia/fisiopatología , Masculino , Calcio/metabolismo
17.
MMWR Morb Mortal Wkly Rep ; 73(38): 830-836, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39325677

RESUMEN

Infants aged <6 months are at increased risk for severe COVID-19 disease but are not yet eligible for COVID-19 vaccination; these children depend upon transplacental transfer of maternal antibody, either from vaccination or infection, for protection. COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) data were analyzed to estimate COVID-19-associated hospitalization rates and identify demographic and clinical characteristics and maternal vaccination status of infants aged <6 months hospitalized with laboratory-confirmed COVID-19. During October 2022-April 2024, COVID-NET identified 1,470 COVID-19-associated hospitalizations among infants aged <6 months. COVID-19-associated hospitalization rates among young infants were higher than rates among any other age group, except adults aged ≥75 years, and are comparable to rates among adults aged 65-74 years. The percentage of hospitalized infants whose mothers had been vaccinated during pregnancy was 18% during October 2022-September 2023 and decreased to <5% during October 2023-April 2024. Severe outcomes among infants hospitalized with COVID-19 occurred frequently: excluding newborns hospitalized at birth, approximately one in five young infants hospitalized with COVID-19 required admission to an intensive care unit, nearly one in 20 required mechanical ventilation, and nine infants died during their COVID-19-associated hospitalization. To help protect pregnant persons and infants too young to be vaccinated, prevention for these groups should focus on ensuring that pregnant persons receive recommended COVID-19 vaccines.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Hospitalización , Vacunación , Humanos , COVID-19/prevención & control , COVID-19/epidemiología , Femenino , Lactante , Hospitalización/estadística & datos numéricos , Embarazo , Recién Nacido , Estados Unidos/epidemiología , Adulto , Masculino , Vacunas contra la COVID-19/administración & dosificación , Vacunación/estadística & datos numéricos , Persona de Mediana Edad , Anciano , Adolescente , Adulto Joven
18.
AIDS Care ; 36(2): 195-203, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37321981

RESUMEN

Mental illness is prevalent among people living with HIV (PLHIV) and hinders engagement in HIV care. While financial incentives are effective at improving mental health and retention in care, the specific effect of such incentives on the mental health of PLHIV lacks quantifiable evidence. We evaluated the impact of a three-arm randomized controlled trial of a financial incentive program on the mental health of adult antiretroviral therapy (ART) initiates in Tanzania. Participants were randomized 1:1:1 into one of two cash incentive (combined; provided monthly conditional on clinic attendance) or the control arm. We measured the prevalence of emotional distress, depression, and anxiety via a difference-in-differences model which quantifies changes in the outcomes by arm over time. Baseline prevalence of emotional distress, depression, and anxiety among the 530 participants (346 intervention, 184 control) was 23.8%, 26.6%, and 19.8%, respectively. The prevalence of these outcomes decreased substantially over the study period; additional benefit of the cash incentives was not detected. In conclusion, poor mental health was common although the prevalence declined rapidly during the first six months on ART. The cash incentives did not increase these improvements, however they may have indirect benefit by motivating early linkage to and retention in care.Clinical Trial Number: NCT03341556.


Asunto(s)
Infecciones por VIH , Motivación , Adulto , Humanos , Tanzanía/epidemiología , Salud Mental , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Ansiedad/epidemiología
19.
Int Urogynecol J ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331149

RESUMEN

INTRODUCTION AND HYPOTHESIS: The objective was to implement an evidence-based peri-partum care bundle for women sustaining obstetric anal sphincter injuries and to evaluate compliance with recommendations for antibiotics use, repair in the operating room, and follow-up before and after implementation. METHODS: This project was reviewed by the Institutional Review Board and determined to be exempt. A clinical care bundle containing education and standardized orders in the electronic medical record was implemented. Characteristics of pre- (October 2017 to September 2019) and post-intervention (October 2019 to August 2021) cohorts were compared and compliance with recommendations for antibiotics use, surgical repair location, and follow-up were evaluated. Chi-squared, Fisher's exact, ANOVA F, and Kruskal-Wallis tests were performed, as indicated. Significance level was p < 0.05. RESULTS: A total of 185 cases were identified. Seventy-five percent of women were nulliparous. Mean gestational age was 39 weeks. Pre- and post-intervention groups did not differ in age, BMI, race, parity, gestational age, comorbidities, birthweight, or delivery type. Ninety-eight cases were identified pre-implementation. Eighty-six (88%) had third-degree lacerations. Post-implementation, 87 cases were identified. Seventy (80%) had third-degree lacerations (p = 0.17). Recommended antibiotic-type use improved from 35% pre-implementation to 93% post-implementation (p < 0.001). Repair in the operating room was similar pre-implementation and post-implementation (16.0% vs 12.6%, p = 0.48). Post-partum follow-up within 2 weeks improved from 16.3% pre-implementation to 52.8% post-implementation and mean time to follow-up was shorter post-implementation than pre-implementation (18 vs 33 days; both p < 0.001). CONCLUSIONS: Implementation of an evidence-based peri-partum care bundle resulted in standardization of care in accordance with established recommendations. Compliance with recommendations for surgical repair in the operating room remained unchanged.

20.
Neurosurg Rev ; 47(1): 188, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658423

RESUMEN

There are several surgical approaches for vestibular schwannoma (VS) resection. However, management has gradually shifted from microsurgical resection, toward surveillance and radiosurgery. One of the arguments against microsurgery via the middle fossa approach (MFA) is the risk of temporal lobe retraction injury or sequelae. Here, we sought to evaluate the incidence of temporal lobe retraction injury or sequela from a MFA via a systematic review of the existing literature. This systematic review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Relevant studies reporting temporal lobe injury or sequela during MFA for VS were identified. Data was aggregated and subsequently analyzed to evaluate the incidence of temporal lobe injury. 22 studies were included for statistical analysis, encompassing 1522 patients that underwent VS resection via MFA. The overall rate of temporal lobe sequelae from this approach was 0.7%. The rate of CSF leak was 5.9%. The rate of wound infection was 0.6%. Meningitis occurred in 1.6% of patients. With the MFA, 92% of patients had good facial outcomes, and 54.9% had hearing preservation. Our series and literature review support that temporal lobe retraction injury or sequelae is an infrequent complication from an MFA for intracanalicular VS resection.


Asunto(s)
Neuroma Acústico , Lóbulo Temporal , Humanos , Neuroma Acústico/cirugía , Lóbulo Temporal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Neuroquirúrgicos/efectos adversos , Fosa Craneal Media/cirugía , Microcirugia/métodos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología
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