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1.
Nature ; 592(7854): 409-413, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33692544

RESUMO

The output of the retina is organized into many detector grids, called 'mosaics', that signal different features of visual scenes to the brain1-4. Each mosaic comprises a single type of retinal ganglion cell (RGC), whose receptive fields tile visual space. Many mosaics arise as pairs, signalling increments (ON) and decrements (OFF), respectively, of a particular visual feature5. Here we use a model of efficient coding6 to determine how such mosaic pairs should be arranged to optimize the encoding of natural scenes. We find that information is maximized when these mosaic pairs are anti-aligned, meaning that the distances between the receptive field centres across mosaics are greater than expected by chance. We tested this prediction across multiple receptive field mosaics acquired using large-scale measurements of the light responses of rat and primate RGCs. ON and OFF RGC pairs with similar feature selectivity had anti-aligned receptive field mosaics, consistent with this prediction. ON and OFF RGC types that encode distinct features have independent mosaics. These results extend efficient coding theory beyond individual cells to predict how populations of diverse types of RGC are spatially arranged.


Assuntos
Retina/citologia , Retina/fisiologia , Campos Visuais/fisiologia , Animais , Feminino , Macaca , Masculino , Modelos Neurológicos , Ratos , Ratos Long-Evans , Células Ganglionares da Retina/fisiologia
2.
Nature ; 600(7890): 630-635, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34937894

RESUMO

Interactions govern the flow of information and the formation of correlations between constituents of many-body quantum systems, dictating phases of matter found in nature and forms of entanglement generated in the laboratory. Typical interactions decay with distance and thus produce a network of connectivity governed by geometry-such as the crystalline structure of a material or the trapping sites of atoms in a quantum simulator1,2. However, many envisioned applications in quantum simulation and computation require more complex coupling graphs including non-local interactions, which feature in models of information scrambling in black holes3-6 and mappings of hard optimization problems onto frustrated classical magnets7-11. Here we describe the realization of programmable non-local interactions in an array of atomic ensembles within an optical cavity, in which photons carry information between atomic spins12-19. By programming the distance dependence of the interactions, we access effective geometries for which the dimensionality, topology and metric are entirely distinct from the physical geometry of the array. As examples, we engineer an antiferromagnetic triangular ladder, a Möbius strip with sign-changing interactions and a treelike geometry inspired by concepts of quantum gravity5,20-22. The tree graph constitutes a toy model of holographic duality21,22, in which the quantum system lies on the boundary of a higher-dimensional geometry that emerges from measured correlations23. Our work provides broader prospects for simulating frustrated magnets and topological phases24, investigating quantum optimization paradigms10,11,25,26 and engineering entangled resource states for sensing and computation27,28.

3.
J Biol Chem ; 299(8): 105030, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37442239

RESUMO

Human growth hormone (hGH) is a pituitary-derived endocrine protein that regulates several critical postnatal physiologic processes including growth, organ development, and metabolism. Following adulthood, GH is also a regulator of multiple pathologies like fibrosis, cancer, and diabetes. Therefore, there is a significant pharmaceutical interest in developing antagonists of hGH action. Currently, there is a single FDA-approved antagonist of the hGH receptor (hGHR) prescribed for treating patients with acromegaly and discovered in our laboratory almost 3 decades ago. Here, we present the first data on the structure and function of a new set of protein antagonists with the full range of hGH actions-dual antagonists of hGH binding to the GHR as well as that of hGH binding to the prolactin receptor. We describe the site-specific PEG conjugation, purification, and subsequent characterization using MALDI-TOF, size-exclusion chromatography, thermostability, and biochemical activity in terms of ELISA-based binding affinities with GHR and prolactin receptor. Moreover, these novel hGHR antagonists display distinct antagonism of GH-induced GHR intracellular signaling in vitro and marked reduction in hepatic insulin-like growth factor 1 output in vivo. Lastly, we observed potent anticancer biological efficacies of these novel hGHR antagonists against human cancer cell lines. In conclusion, we propose that these new GHR antagonists have potential for development towards multiple clinical applications related to GH-associated pathologies.


Assuntos
Hormônio do Crescimento Humano , Receptores da Prolactina , Humanos , Proteínas de Transporte/química , Linhagem Celular , Hormônio do Crescimento Humano/antagonistas & inibidores , Hormônio do Crescimento Humano/química , Prolactina/química , Receptores da Prolactina/antagonistas & inibidores , Receptores da Prolactina/química , Receptores da Somatotropina/química , Polietilenoglicóis/química
4.
Proc Biol Sci ; 291(2027): 20240911, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043237

RESUMO

Cognitive skills, such as innovative problem-solving, are hypothesized to aid animals in urban environments. However, the significance of innovation in wild populations, and its expression across individuals and socio-ecological conditions, is poorly understood. To identify how and when innovation arises in urban-dwelling species, we used advanced technologies and new testing and analytical methods to evaluate innovative problem-solving abilities of wild raccoons (Procyon lotor). We deployed multi-compartment puzzle boxes with either one or multiple solution types and identified raccoons using radio frequency identification. Raccoons solved these novel extractive foraging tasks, and their success was influenced by age and exploratory diversity. Successful raccoons always discovered multiple different solution types, highlighting flexible problem-solving. Using a unique, comparative sequence analysis approach, we found that variation in raccoon solving techniques was greater between individuals than within individuals, and this self-similarity intensified during times of competition. Finally, the inclusion of an easier solution in the multi-solution trials enabled previously unsuccessful raccoons to bootstrap their learning and successfully open multiple difficult solutions. Our study suggests that innovative problem-solving is probably influenced by many factors and has provided novel field and analytical methods, as well as new insights on the socio-ecological dynamics of urban populations.


Assuntos
Resolução de Problemas , Guaxinins , Animais , Guaxinins/fisiologia , Masculino , Individualidade , Feminino
5.
MMWR Morb Mortal Wkly Rep ; 73(35): 769-773, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39236058

RESUMO

Beginning in late 2023, Oropouche virus was identified as the cause of large outbreaks in Amazon regions with known endemic transmission and in new areas in South America and the Caribbean. The virus is spread to humans by infected biting midges and some mosquito species. Although infection typically causes a self-limited febrile illness, reports of two deaths in patients with Oropouche virus infection and vertical transmission associated with adverse pregnancy outcomes have raised concerns about the threat of this virus to human health. In addition to approximately 8,000 locally acquired cases in the Americas, travel-associated Oropouche virus disease cases have recently been identified in European travelers returning from Cuba and Brazil. As of August 16, 2024, a total of 21 Oropouche virus disease cases were identified among U.S. travelers returning from Cuba. Most patients initially experienced fever, myalgia, and headache, often with other symptoms including arthralgia, diarrhea, nausea or vomiting, and rash. At least three patients had recurrent symptoms after the initial illness, a common characteristic of Oropouche virus disease. Clinicians and public health jurisdictions should be aware of the occurrence of Oropouche virus disease in U.S. travelers and request testing for suspected cases. Travelers should prevent insect bites when traveling, and pregnant persons should consider deferring travel to areas experiencing outbreaks of Oropouche virus disease.


Assuntos
Infecções por Bunyaviridae , Humanos , Estados Unidos/epidemiologia , Feminino , Adulto , Masculino , Infecções por Bunyaviridae/epidemiologia , Pessoa de Meia-Idade , Idoso , Orthobunyavirus/isolamento & purificação , Viagem , Adulto Jovem , Doença Relacionada a Viagens , Surtos de Doenças , Cuba/epidemiologia
6.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39000545

RESUMO

Chemotherapy treatment against pancreatic ductal adenocarcinoma (PDAC) is thwarted by tumoral activation of multiple therapy resistance pathways. The growth hormone (GH)-GH receptor (GHR) pair is a covert driver of multimodal therapy resistance in cancer and is overexpressed in PDAC tumors, yet the therapeutic potential of targeting the same has not been explored. Here, we report that GHR expression is a negative prognostic factor in patients with PDAC. Combinations of gemcitabine with different GHR antagonists (GHRAs) markedly improve therapeutic outcomes in nude mice xenografts. Employing cultured cells, mouse xenografts, and analyses of the human PDAC transcriptome, we identified that attenuation of the multidrug transporter and epithelial-to-mesenchymal transition programs in the tumors underlie the observed augmentation of chemotherapy efficacy by GHRAs. Moreover, in human PDAC patients, GHR expression strongly correlates with a gene signature of tumor promotion and immune evasion, which corroborate with that in syngeneic tumors in wild-type vs. GH transgenic mice. Overall, we found that GH action in PDAC promoted a therapy-refractory gene signature in vivo, which can be effectively attenuated by GHR antagonism. Our results collectively present a proof of concept toward considering GHR antagonists to improve chemotherapeutic outcomes in the highly chemoresistant PDAC.


Assuntos
Carcinoma Ductal Pancreático , Desoxicitidina , Gencitabina , Neoplasias Pancreáticas , Receptores da Somatotropina , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Camundongos , Receptores da Somatotropina/metabolismo , Receptores da Somatotropina/antagonistas & inibidores , Receptores da Somatotropina/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Camundongos Nus , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Feminino
7.
Clin Infect Dis ; 76(3): e1320-e1327, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35883256

RESUMO

BACKGROUND: Cache Valley virus (CVV) is a mosquito-borne virus that is a rare cause of disease in humans. In the fall of 2020, a patient developed encephalitis 6 weeks following kidney transplantation and receipt of multiple blood transfusions. METHODS: After ruling out more common etiologies, metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) was performed. We reviewed the medical histories of the index kidney recipient, organ donor, and recipients of other organs from the same donor and conducted a blood traceback investigation to evaluate blood transfusion as a possible source of infection in the kidney recipient. We tested patient specimens using reverse-transcription polymerase chain reaction (RT-PCR), the plaque reduction neutralization test, cell culture, and whole-genome sequencing. RESULTS: CVV was detected in CSF from the index patient by mNGS, and this result was confirmed by RT-PCR, viral culture, and additional whole-genome sequencing. The organ donor and other organ recipients had no evidence of infection with CVV by molecular or serologic testing. Neutralizing antibodies against CVV were detected in serum from a donor of red blood cells received by the index patient immediately prior to transplant. CVV neutralizing antibodies were also detected in serum from a patient who received the co-component plasma from the same blood donation. CONCLUSIONS: Our investigation demonstrates probable CVV transmission through blood transfusion. Clinicians should consider arboviral infections in unexplained meningoencephalitis after blood transfusion or organ transplantation. The use of mNGS might facilitate detection of rare, unexpected infections, particularly in immunocompromised patients.


Assuntos
Vírus Bunyamwera , Transplante de Rim , Meningoencefalite , Humanos , Anticorpos Neutralizantes , Transfusão de Sangue , Transplante de Rim/efeitos adversos , Meningoencefalite/diagnóstico
9.
Hum Factors ; : 187208231219184, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052019

RESUMO

OBJECTIVE: This study examined the impact of monitoring instructions when using an automated driving system (ADS) and road obstructions on post take-over performance in near-miss scenarios. BACKGROUND: Past research indicates partial ADS reduces the driver's situation awareness and degrades post take-over performance. Connected vehicle technology may alert drivers to impending hazards in time to safely avoid near-miss events. METHOD: Forty-eight licensed drivers using ADS were randomly assigned to either the active driving or passive driving condition. Participants navigated eight scenarios with or without a visual obstruction in a distributed driving simulator. The experimenter drove the other simulated vehicle to manually cause near-miss events. Participants' mean longitudinal velocity, standard deviation of longitudinal velocity, and mean longitudinal acceleration were measured. RESULTS: Participants in passive ADS group showed greater, and more variable, deceleration rates than those in the active ADS group. Despite a reliable audiovisual warning, participants failed to slow down in the red-light running scenario when the conflict vehicle was occluded. Participant's trust in the automated driving system did not vary between the beginning and end of the experiment. CONCLUSION: Drivers interacting with ADS in a passive manner may continue to show increased and more variable deceleration rates in near-miss scenarios even with reliable connected vehicle technology. Future research may focus on interactive effects of automated and connected driving technologies on drivers' ability to anticipate and safely navigate near-miss scenarios. APPLICATION: Designers of automated and connected vehicle technologies may consider different timing and types of cues to inform the drivers of imminent hazard in high-risk scenarios for near-miss events.

10.
Pituitary ; 25(1): 1-51, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34797529

RESUMO

Much of our understanding of GH's action stems from animal models and the generation and characterization of genetically altered or modified mice. Manipulation of genes in the GH/IGF1 family in animals started in 1982 when the first GH transgenic mice were produced. Since then, multiple laboratories have altered mouse DNA to globally disrupt Gh, Ghr, and other genes upstream or downstream of GH or its receptor. The ability to stay current with the various genetically manipulated mouse lines within the realm of GH/IGF1 research has been daunting. As such, this review attempts to consolidate and summarize the literature related to the initial characterization of many of the known gene-manipulated mice relating to the actions of GH, PRL and IGF1. We have organized the mouse lines by modifications made to constituents of the GH/IGF1 family either upstream or downstream of GHR or to the GHR itself. Available data on the effect of altered gene expression on growth, GH/IGF1 levels, body composition, reproduction, diabetes, metabolism, cancer, and aging are summarized. For the ease of finding this information, key words are highlighted in bold throughout the main text for each mouse line and this information is summarized in Tables 1, 2, 3 and 4. Most importantly, the collective data derived from and reported for these mice have enhanced our understanding of GH action.


Assuntos
Hormônio do Crescimento , Receptores da Somatotropina , Animais , Composição Corporal , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Transgênicos , Modelos Animais , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo
11.
Retina ; 42(5): 899-905, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35067611

RESUMO

PURPOSE: To examine outcomes of eyes with neovascular age-related macular degeneration that were switched to brolucizumab because of an unsatisfactory response to bevacizumab, ranibizumab, and/or aflibercept and then switched back because of the presence or risk of intraocular inflammation. METHODS: Retrospective case series of 51 eyes. Visual acuity and retinal anatomy on optical coherence tomography were recorded at the first brolucizumab injection (T1), the final brolucizumab injection (T2), and 6 months following the final brolucizumab injection (T3). RESULTS: At T2, 41 eyes (41/51%, 80%) had decreased subretinal fluid (31 eyes), intraretinal fluid (12 eyes), or pigment epithelial detachment height (12 eyes). At T3, decreased subretinal fluid was sustained in 17 eyes (17/31%, 55%), decreased intraretinal fluid was sustained in eight eyes (8/12%, 67%), and decreased pigment epithelial detachment height was sustained in eight eyes (8/12%, 67%). Mean logarithm of the minimum angle of resolution visual acuity at T1, T2, and T3 was 0.396 (∼20/50), 0.441 (∼20/55), and 0.468 (∼20/59), respectively. During the brolucizumab treatment period, 11 eyes (11/51%, 22%) developed intraocular inflammation, including one case of retinal vasculitis. CONCLUSION: Interim treatment with brolucizumab resulted in anatomical improvements in 41 eyes (41/51%, 80%) that were maintained in 22 of these eyes (22/41%, 54%) for at least 6 months after switching back to the original anti-vascular endothelial growth factor therapeutic. There were no corresponding significant changes in visual acuity.


Assuntos
Inibidores da Angiogênese , Descolamento Retiniano , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados , Humanos , Inflamação/tratamento farmacológico , Injeções Intravítreas , Descolamento Retiniano/tratamento farmacológico , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular
12.
Emerg Infect Dis ; 27(7): 1886-1892, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34152960

RESUMO

Eastern equine encephalitis virus (EEEV) is an arbovirus in the family Togaviridae, genus Alphavirus, found in North America and associated with freshwater/hardwood swamps in the Atlantic, Gulf Coast, and Great Lakes regions. EEEV disease in humans is rare but causes substantial illness and death. To investigate the molecular epidemiology and microevolution of EEEV from a fatal case in Alabama, USA, in 2019, we used next-generation sequencing of serum and cerebrospinal fluid (CSF). Phylogenetic inference indicated that the infecting strain may be closely related to isolates from Florida detected during 2010-2014, suggesting potential seeding from Florida. EEEV detected in serum displayed a higher degree of variability with more single-nucleotide variants than that detected in the CSF. These data refine our knowledge of EEEV molecular epidemiologic dynamics in the Gulf Coast region and demonstrate potential quasispecies bottlenecking within the central nervous system of a human host.


Assuntos
Vírus da Encefalite Equina do Leste , Alabama , Animais , Florida , Cavalos , Humanos , América do Norte , Filogenia
13.
Mol Microbiol ; 114(3): 480-494, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32426863

RESUMO

Chaperone networks are required for the shearing and generation of transmissible propagons from pre-existing prion aggregates. However, other cellular networks needed for maintaining yeast prions are largely uncharacterized. Here, we establish a novel role for actin networks in prion maintenance. The [PIN+ ] prion, also known as [RNQ+ ], exists as stable variants dependent upon the chaperone machinery for the transmission of propagons to daughter cells during cell division and cytoplasmic transfer. Loss of the Hsp104 molecular chaperone leads to the growth of prion particles until they are too large to be transmitted. Here, we isolated a unique [PIN+ ] variant, which is unstable in actin mutants. This prion loss is observed over many generations, and coincides with the detection of both high molecular weight species of Rnq1 and large visible aggregates that are asymmetrically retained during cell division. Our data suggest that the irregular actin networks found in these mutants may influence propagon number by slowly permitting aggregate growth over time, resulting in the generation of nontransmissible large aggregates. Thus, we show the potential contribution of cytoskeletal networks in the transmission of prion propagons, which parallels models that have been proposed for cell-to-cell transmission of small amyloids in neurodegenerative protein aggregation diseases.


Assuntos
Citoesqueleto de Actina/metabolismo , Príons/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Amiloide/metabolismo , Divisão Celular , Proteínas de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Mutação , Príons/genética , Agregados Proteicos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
14.
Am J Hum Genet ; 102(6): 1062-1077, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29805046

RESUMO

Missense DNA variants have variable effects upon protein function. Consequently, interpreting their pathogenicity is challenging, especially when they are associated with disease variability. To determine the degree to which functional assays inform interpretation, we analyzed 48 CFTR missense variants associated with variable expressivity of cystic fibrosis (CF). We assessed function in a native isogenic context by evaluating CFTR mutants that were stably expressed in the genome of a human airway cell line devoid of endogenous CFTR expression. 21 of 29 variants associated with full expressivity of the CF phenotype generated <10% wild-type CFTR (WT-CFTR) function, a conservative threshold for the development of life-limiting CF lung disease, and five variants had moderately decreased function (10% to ∼25% WT-CFTR). The remaining three variants in this group unexpectedly had >25% WT-CFTR function; two were higher than 75% WT-CFTR. As expected, 14 of 19 variants associated with partial expressivity of CF had >25% WT-CFTR function; however, four had minimal to no effect on CFTR function (>75% WT-CFTR). Thus, 6 of 48 (13%) missense variants believed to be disease causing did not alter CFTR function. Functional studies substantially refined pathogenicity assignment with expert annotation and criteria from the American College of Medical Genetics and Genomics and Association for Molecular Pathology. However, four algorithms (CADD, REVEL, SIFT, and PolyPhen-2) could not differentiate between variants that caused severe, moderate, or minimal reduction in function. In the setting of variable expressivity, these results indicate that functional assays are essential for accurate interpretation of missense variants and that current prediction tools should be used with caution.


Assuntos
Bioensaio/métodos , Regulação da Expressão Gênica , Mutação de Sentido Incorreto/genética , Algoritmos , Linhagem Celular , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Anotação de Sequência Molecular , Proteínas Mutantes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Padrões de Referência
15.
Opt Lett ; 46(15): 3721-3724, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329265

RESUMO

Dynamic spatial light modulators (SLMs) are capable of precisely modulating a beam of light by tuning the phase or intensity of an array of pixels in parallel. They can be utilized in applications ranging from image projection to beam front aberration and microscopic particle manipulation with optical tweezers. However, conventional dynamic SLMs are typically incompatible with high-power sources, as they contain easily damaged optically absorbing components. To address this, we present an SLM that utilizes a viscous film with a local thickness controlled via thermocapillary dewetting. The film is reflowable and can cycle through different patterns, representing, to the best of our knowledge, the first steps towards a dynamic optical device based on the thermocapillary dewetting mechanism.

16.
PLoS Genet ; 14(11): e1007723, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30444886

RESUMO

CFTR modulators have revolutionized the treatment of individuals with cystic fibrosis (CF) by improving the function of existing protein. Unfortunately, almost half of the disease-causing variants in CFTR are predicted to introduce premature termination codons (PTC) thereby causing absence of full-length CFTR protein. We hypothesized that a subset of nonsense and frameshift variants in CFTR allow expression of truncated protein that might respond to FDA-approved CFTR modulators. To address this concept, we selected 26 PTC-generating variants from four regions of CFTR and determined their consequences on CFTR mRNA, protein and function using intron-containing minigenes expressed in 3 cell lines (HEK293, MDCK and CFBE41o-) and patient-derived conditionally reprogrammed primary nasal epithelial cells. The PTC-generating variants fell into five groups based on RNA and protein effects. Group A (reduced mRNA, immature (core glycosylated) protein, function <1% (n = 5)) and Group B (normal mRNA, immature protein, function <1% (n = 10)) variants were unresponsive to modulator treatment. However, Group C (normal mRNA, mature (fully glycosylated) protein, function >1% (n = 5)), Group D (reduced mRNA, mature protein, function >1% (n = 5)) and Group E (aberrant RNA splicing, mature protein, function > 1% (n = 1)) variants responded to modulators. Increasing mRNA level by inhibition of NMD led to a significant amplification of modulator effect upon a Group D variant while response of a Group A variant was unaltered. Our work shows that PTC-generating variants should not be generalized as genetic 'nulls' as some may allow generation of protein that can be targeted to achieve clinical benefit.


Assuntos
Códon sem Sentido , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Mutação da Fase de Leitura , Heterogeneidade Genética , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Animais , Linhagem Celular , Fibrose Cística/metabolismo , Fibrose Cística/terapia , Regulador de Condutância Transmembrana em Fibrose Cística/química , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Éxons , Expressão Gênica , Humanos , Degradação do RNAm Mediada por Códon sem Sentido , Splicing de RNA
17.
Folia Phoniatr Logop ; 73(4): 335-354, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32756053

RESUMO

INTRODUCTION: High demand for speech-language pathology means children sometimes wait over 12 months for services, missing out on timely support. Waiting can be a time of stress, concern, and powerlessness for caregivers. Provision of information via a website may support families and encourage active waiting. OBJECTIVE: The aim of this study was to compare children's speech, intelligibility, language, and literacy outcomes, and caregivers' satisfaction and empowerment in active versus passive waiting conditions. METHODS: Ninety-seven preschool-aged children referred to a community health speech-language pathology service in Australia were screened for eligibility. Eligible children (n =42) with speech/language difficulties were randomly allocated to: (a) active waiting (provision of a purpose-built website; n = 20), or (b) passive waiting (control group; n = 22). Pre- and post-assessments (after 6 months on a waiting list) were completed with children and caregivers by a speech-language pathologist blinded to group allocations. RESULTS: Intention to treat (n =36) and per-protocol analyses (n =30) were conducted to measure group differences in child and caregiver outcomes at post-assessment using one-way ANCOVA, controlling for baseline scores. There were no statistically significant differences between groups for children's speech, intelligibility, language, and literacy, or caregivers' empowerment and satisfaction. Children in both groups made minimal gains over 6 months. CONCLUSIONS: Provision of an active waiting website did not lead to statistically significant change in child or caregiver outcomes, and children in both groups made little progress over a 6-month period. Early speech-language pathology intervention delivered with appropriate dosage is needed to optimise children's outcomes. Until timely and effective speech-language pathology intervention can be provided for all who need it, provision of early assessments may be beneficial. There remains a need for effective ways to support children and families on waiting lists.


Assuntos
Patologia da Fala e Linguagem , Cuidadores , Criança , Pré-Escolar , Humanos , Fala , Distúrbios da Fala/terapia , Fonoterapia
18.
Am J Hum Genet ; 100(5): 751-765, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28475858

RESUMO

We developed a variant-annotation method that combines sequence-based machine-learning classification with a context-dependent algorithm for selecting splice variants. Our approach is distinctive in that it compares the splice potential of a sequence bearing a variant with the splice potential of the reference sequence. After training, classification accurately identified 168 of 180 (93.3%) canonical splice sites of five genes. The combined method, CryptSplice, identified and correctly predicted the effect of 18 of 21 (86%) known splice-altering variants in CFTR, a well-studied gene whose loss-of-function variants cause cystic fibrosis (CF). Among 1,423 unannotated CFTR disease-associated variants, the method identified 32 potential exonic cryptic splice variants, two of which were experimentally evaluated and confirmed. After complete CFTR sequencing, the method found three cryptic intronic splice variants (one known and two experimentally verified) that completed the molecular diagnosis of CF in 6 of 14 individuals. CryptSplice interrogation of sequence data from six individuals with X-linked dyskeratosis congenita caused by an unknown disease-causing variant in DKC1 identified two splice-altering variants that were experimentally verified. To assess the extent to which disease-associated variants might activate cryptic splicing, we selected 458 pathogenic variants and 348 variants of uncertain significance (VUSs) classified as high confidence from ClinVar. Splice-site activation was predicted for 129 (28%) of the pathogenic variants and 75 (22%) of the VUSs. Our findings suggest that cryptic splice-site activation is more common than previously thought and should be routinely considered for all variants within the transcribed regions of genes.


Assuntos
Proteínas de Ciclo Celular/genética , Biologia Computacional , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Variação Genética , Proteínas Nucleares/genética , Sítios de Splice de RNA , Algoritmos , Proteínas de Ciclo Celular/metabolismo , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Disceratose Congênita/genética , Éxons , Regulação da Expressão Gênica , Loci Gênicos , Genômica , Células HEK293 , Humanos , Íntrons , Mutação de Sentido Incorreto , Proteínas Nucleares/metabolismo , Splicing de RNA , Análise de Sequência de DNA , Máquina de Vetores de Suporte
19.
Phys Rev Lett ; 125(6): 060402, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32845652

RESUMO

Using an ensemble of atoms in an optical cavity, we engineer a family of nonlocal Heisenberg Hamiltonians with continuously tunable anisotropy of the spin-spin couplings. We thus gain access to a rich phase diagram, including a paramagnetic-to-ferromagnetic Ising phase transition that manifests as a diverging magnetic susceptibility at the critical point. The susceptibility displays a symmetry between Ising interactions and XY (spin-exchange) interactions of the opposite sign, which is indicative of the spatially extended atomic system behaving as a single collective spin. Images of the magnetization dynamics show that spin-exchange interactions protect the coherence of the collective spin, even against inhomogeneous fields that completely dephase the noninteracting and Ising systems. Our results underscore prospects for harnessing spin-exchange interactions to enhance the robustness of spin squeezing protocols.

20.
AIDS Care ; 32(4): 452-461, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31640396

RESUMO

In the era of widespread antiretroviral therapy (ART), consequences of being HIV-exposed is unclear for children, especially in rural communities. A population sample of consecutive births (470/493) in the Eastern Cape of South Africa (SA) were recruited and reassessed at five points over the first 24 months. Maternal and child outcomes between mothers living with and without HIV were assessed using multiple linear and logistic regressions. At birth, 28% of the sample was mothers living with HIV and five additional mothers seroconverted. All mothers living with HIV reported taking ART. The rate of depressed mood and IPV was similar across serostatus. However, mothers living with HIV significantly decreased their alcohol use after learning about their pregnancy and were more likely to exclusively breastfeed when compared to mothers without HIV. Despite maternal HIV status, children had similar growth across the first 24 months of life. Future work is needed to assess if these developmental trajectories will persist.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Aleitamento Materno/estatística & dados numéricos , Saúde da Criança , Infecções por HIV/tratamento farmacológico , Saúde Materna , Mães/estatística & dados numéricos , População Rural/estatística & dados numéricos , Criança , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Humanos , Saúde Mental , Avaliação de Resultados em Cuidados de Saúde , Gravidez , África do Sul/epidemiologia , Adulto Jovem
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