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1.
Immunity ; 51(1): 119-130.e5, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31231034

RESUMO

Tissue-resident macrophages require specific milieus for the maintenance of defining gene-expression programs. Expression of the transcription factor GATA6 is required for the homeostasis, function and localization of peritoneal cavity-resident macrophages. Gata6 expression is maintained in a non-cell autonomous manner and is elicited by the vitamin A metabolite, retinoic acid. Here, we found that the GATA6 transcriptional program is a common feature of macrophages residing in all visceral body cavities. Retinoic acid-dependent and -independent hallmark genes of GATA6+ macrophages were induced by mesothelial and fibroblastic stromal cells that express the transcription factor Wilms' Tumor 1 (WT1), which drives the expression of two rate-limiting enzymes in retinol metabolism. Depletion of Wt1+ stromal cells reduced the frequency of GATA6+ macrophages in the peritoneal, pleural and pericardial cavities. Thus, Wt1+ mesothelial and fibroblastic stromal cells constitute essential niche components supporting the tissue-specifying transcriptional landscape and homeostasis of cavity-resident macrophages.


Assuntos
Fator de Transcrição GATA6/metabolismo , Macrófagos/fisiologia , Pericárdio/imunologia , Cavidade Peritoneal/fisiologia , Cavidade Pleural/imunologia , Proteínas Repressoras/metabolismo , Células Estromais/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Fator de Transcrição GATA6/genética , Homeostase , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Repressoras/genética , Tretinoína/metabolismo , Proteínas WT1
2.
Proc Natl Acad Sci U S A ; 121(19): e2315168121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38683997

RESUMO

Accurate prediction of the efficacy of immunotherapy for cancer patients through the characterization of both genetic and phenotypic heterogeneity in individual patient cells holds great promise in informing targeted treatments, and ultimately in improving care pathways and clinical outcomes. Here, we describe the nanoplatform for interrogating living cell host-gene and (micro-)environment (NICHE) relationships, that integrates micro- and nanofluidics to enable highly efficient capture of circulating tumor cells (CTCs) from blood samples. The platform uses a unique nanopore-enhanced electrodelivery system that efficiently and rapidly integrates stable multichannel fluorescence probes into living CTCs for in situ quantification of target gene expression, while on-chip coculturing of CTCs with immune cells allows for the real-time correlative quantification of their phenotypic heterogeneities in response to immune checkpoint inhibitors (ICI). The NICHE microfluidic device provides a unique ability to perform both gene expression and phenotypic analysis on the same single cells in situ, allowing us to generate a predictive index for screening patients who could benefit from ICI. This index, which simultaneously integrates the heterogeneity of single cellular responses for both gene expression and phenotype, was validated by clinically tracing 80 non-small cell lung cancer patients, demonstrating significantly higher AUC (area under the curve) (0.906) than current clinical reference for immunotherapy prediction.


Assuntos
Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/metabolismo , Microfluídica/métodos , Análise de Célula Única/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/sangue , Fenótipo , Linhagem Celular Tumoral , Imunoterapia/métodos , Perfilação da Expressão Gênica/métodos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/sangue , Técnicas Analíticas Microfluídicas/métodos , Técnicas Analíticas Microfluídicas/instrumentação
3.
Cell ; 143(5): 826-36, 2010 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-21111240

RESUMO

The Reelin ligand regulates a Dab1-dependent signaling pathway required for brain lamination and normal dendritogenesis, but the specific mechanisms underlying these actions remain unclear. We find that Stk25, a modifier of Reelin-Dab1 signaling, regulates Golgi morphology and neuronal polarization as part of an LKB1-Stk25-Golgi matrix protein 130 (GM130) signaling pathway. Overexpression of Stk25 induces Golgi condensation and multiple axons, both of which are rescued by Reelin treatment. Reelin stimulation of cultured neurons induces the extension of the Golgi into dendrites, which is suppressed by Stk25 overexpression. In vivo, Reelin and Dab1 are required for the normal extension of the Golgi apparatus into the apical dendrites of hippocampal and neocortical pyramidal neurons. This demonstrates that the balance between Reelin-Dab1 signaling and LKB1-Stk25-GM130 regulates Golgi dispersion, axon specification, and dendrite growth and provides insights into the importance of the Golgi apparatus for cell polarization.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Complexo de Golgi/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Serina Endopeptidases/metabolismo , Animais , Linhagem Celular , Separação Celular , Células Cultivadas , Hipocampo/metabolismo , Humanos , Camundongos , Ratos , Proteína Reelina
4.
Cell ; 140(4): 477-90, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20178741

RESUMO

Current models imply that the FERM domain protein Merlin, encoded by the tumor suppressor NF2, inhibits mitogenic signaling at or near the plasma membrane. Here, we show that the closed, growth-inhibitory form of Merlin accumulates in the nucleus, binds to the E3 ubiquitin ligase CRL4(DCAF1), and suppresses its activity. Depletion of DCAF1 blocks the promitogenic effect of inactivation of Merlin. Conversely, enforced expression of a Merlin-insensitive mutant of DCAF1 counteracts the antimitogenic effect of Merlin. Re-expression of Merlin and silencing of DCAF1 implement a similar, tumor-suppressive program of gene expression. Tumor-derived mutations invariably disrupt Merlin's ability to interact with or inhibit CRL4(DCAF1). Finally, depletion of DCAF1 inhibits the hyperproliferation of Schwannoma cells from NF2 patients and suppresses the oncogenic potential of Merlin-deficient tumor cell lines. We propose that Merlin suppresses tumorigenesis by translocating to the nucleus to inhibit CRL4(DCAF1).


Assuntos
Proteínas de Transporte/metabolismo , Genes Supressores de Tumor , Mesotelioma/metabolismo , Neurilemoma/metabolismo , Neurofibromina 2/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Proteínas de Transporte/química , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Humanos , Modelos Moleculares , Proteínas Serina-Treonina Quinases , Ubiquitina-Proteína Ligases
5.
Ann Clin Microbiol Antimicrob ; 23(1): 28, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555443

RESUMO

BACKGROUND: Neisseria meningitidis can cause life-threatening meningococcal meningitis and meningococcemia. Old standard microbiological results from CSF/blood cultures are time consuming. This study aimed to combine the sensitivity of loop-mediated isothermal nucleic acid amplification (LAMP) with the specificity of CRISPR/Cas12a cleavage to demonstrate a reliable diagnostic assay for rapid detection of N. meningitidis. METHODS: A total of n = 139 samples were collected from patients with suspected meningococcal disease and were used for evaluation. The extracted DNA was subjected to qualitative real-time PCR, targeting capsular transporter gene (ctrA) of N. meningitidis. LAMP-specific primer pairs, also targeting the ctrA, were designed and the LAMP products were subjected to CRISPR/Cas12 cleavage reaction. the readout was on a lateral flow strip. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of LAMP-CRISPR/Cas was compared with real-time PCR assays. The limit of detection (LOD) was established with serial dilutions of the target N. meningitidis DNA and calculated by Probit regression analysis. RESULTS: Six LAMP assay-specific primers were developed targeting the ctrA gene of N. meningitidis, which is conserved in all meningococcal serogroups. The LAMP primers did not amplify DNA from other bacterial DNA tested, showing 100% specificity. The use of 0.4 M betaine increased the sensitivity and stability of the reaction. LAMP-CRISPR/Cas detected meningococcal serogroups (B, C, W). The assay showed no cross-reactivity and was specific for N. meningitidis. The LOD was 74 (95% CI: 47-311) N. meningitidis copies. The LAMP-CRISPR/Cas performed well compared to the gold standard. In the 139 samples from suspected patients, the sensitivity and specificity of the test were 91% and 99% respectively. CONCLUSION: This developed and optimized method can complement for the available gold standard for the timely diagnosis of meningococcal meningitis and meningococcemia.


Assuntos
Meningite Meningocócica , Infecções Meningocócicas , Neisseria meningitidis , Sepse , Humanos , Neisseria meningitidis/genética , Meningite Meningocócica/diagnóstico , Meningite Meningocócica/microbiologia , Infecções Meningocócicas/diagnóstico , Infecções Meningocócicas/microbiologia , Sensibilidade e Especificidade , DNA Bacteriano/genética
6.
J Inherit Metab Dis ; 46(4): 720-734, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37078466

RESUMO

Late-infantile neuronal ceroid lipofuscinosis (LINCL) and juvenile neuronal ceroid lipofuscinosis (JNCL) are inherited neurodegenerative diseases caused by mutations in the genes encoding lysosomal proteins tripeptidyl peptidase 1 (TPP1) and CLN3 protein, respectively. TPP1 is well-understood and, aided by animal models that accurately recapitulate the human disease, enzyme replacement therapy has been approved and other promising therapies are emerging. In contrast, there are no effective treatments for JNCL, partly because the function of the CLN3 protein remains unknown but also because animal models have attenuated disease and lack robust survival phenotypes. Mouse models for LINCL and JNCL, with mutations in Tpp1 and Cln3, respectively, have been thoroughly characterized but the phenotype of a double Cln3/Tpp1 mutant remains unknown. We created this double mutant and find that its phenotype is essentially indistinguishable from the single Tpp1-/- mutant in terms of survival and brain pathology. Analysis of brain proteomic changes in the single Tpp1-/- and double Cln3-/- ;Tpp1-/- mutants indicates largely overlapping sets of altered proteins and reinforces earlier studies that highlight GPNMB, LYZ2, and SERPINA3 as promising biomarker candidates in LINCL while several lysosomal proteins including SMPD1 and NPC1 appear to be altered in the Cln3-/- animals. An unexpected finding was that Tpp1 heterozygosity significantly decreased lifespan of the Cln3-/- mouse. The truncated survival of this mouse model makes it potentially useful in developing therapies for JNCL using survival as an endpoint. In addition, this model may also provide insights into CLN3 protein function and its potential functional interactions with TPP1.


Assuntos
Lipofuscinoses Ceroides Neuronais , Tripeptidil-Peptidase 1 , Animais , Camundongos , Encéfalo/patologia , Modelos Animais de Doenças , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Chaperonas Moleculares/genética , Mutação , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/patologia , Proteômica
7.
Telemed J E Health ; 29(6): 912-920, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36779974

RESUMO

Background: Despite its strong growth in many parts of the world, mobile health access is still limited in low- and middle-income countries. Among the many factors restricting implementation are the lack of information security, insufficient evidence base, low sensitization, and user acceptance. Limited evidence has been obtained on current practices, perceptions, and user acceptability in such settings. The aim of this study was therefore to evaluate the knowledge, attitude, and perceptions on mobile health use among health workers and veterinary officers in Uganda. Materials and Methods: A cross-section study was carried out, targeting health practitioners in both hospitals and veterinary laboratories/clinics. A structured questionnaire was used to collect data from the Central, Eastern, Northern, and Western representative regions. Interviews with selected health workers were also conducted as well as a focused group discussion. Results: Of the 120 health practitioners that were targeted, a total of 80 health workers and 7 veterinary practitioners participated in the study of which 46% were men and 54% women. Majority of the health workers had encountered m-health but had never used it, whereas the 15 practitioners who had used it before the survey did not use it for disease diagnosis in hospitals but used it for ordering medicine online, for patient consultations with the doctors, result interpretation, tracking women menstrual cycles, tuberculosis assessment. Discussion and Conclusion: Participants expressed significant interest in mobile health as it addresses key challenges including challenges with management of patient data, and long patient queues, which would ultimately improve service delivery. However, there is some skepticism about access as many rural facilities lack access to smartphones and stable internet.


Assuntos
Médicos , Telemedicina , Masculino , Humanos , Feminino , Uganda , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde
8.
J Pharmacol Exp Ther ; 382(3): 277-286, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35717448

RESUMO

Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome B; OMIM #252920) is a lethal, pediatric, neuropathic, autosomal recessive, and lysosomal storage disease with no approved therapy. Patients are deficient in the activity of N-acetyl-alpha-glucosaminidase (NAGLU; EC 3.2.150), necessary for normal lysosomal degradation of the glycosaminoglycan heparan sulfate (HS). Tralesinidase alfa (TA), a fusion protein comprised of recombinant human NAGLU and a modified human insulin-like growth factor 2, is in development as an enzyme replacement therapy that is administered via intracerebroventricular (ICV) infusion, thus circumventing the blood brain barrier. Previous studies have confirmed ICV infusion results in widespread distribution of TA throughout the brains of mice and nonhuman primates. We assessed the long-term tolerability, pharmacology, and clinical efficacy of TA in a canine model of MPS IIIB over a 20-month study. Long-term administration of TA was well tolerated as compared with administration of vehicle. TA was widely distributed across brain regions, which was confirmed in a follow-up 8-week pharmacokinetic/pharmacodynamic study. MPS IIIB dogs treated for up to 20 months had near-normal levels of HS and nonreducing ends of HS in cerebrospinal fluid and central nervous system (CNS) tissues. TA-treated MPS IIIB dogs performed better on cognitive tests and had improved CNS pathology and decreased cerebellar volume loss relative to vehicle-treated MPS IIIB dogs. These findings demonstrate the ability of TA to prevent or limit the biochemical, pathologic, and cognitive manifestations of canine MPS IIIB disease, thus providing support of its potential long-term tolerability and efficacy in MPS IIIB subjects. SIGNIFICANCE STATEMENT: This work illustrates the efficacy and tolerability of tralesinidase alfa as a potential therapeutic for patients with mucopolysaccharidosis type IIIB (MPS IIIB) by documenting that administration to the central nervous system of MPS IIIB dogs prevents the accumulation of disease-associated glycosaminoglycans in lysosomes, hepatomegaly, cerebellar atrophy, and cognitive decline.


Assuntos
Mucopolissacaridose III , Animais , Encéfalo/metabolismo , Criança , Modelos Animais de Doenças , Cães , Terapia de Reposição de Enzimas , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/líquido cefalorraquidiano , Heparitina Sulfato/uso terapêutico , Humanos , Mucopolissacaridose III/tratamento farmacológico , Mucopolissacaridose III/patologia
9.
Adv Exp Med Biol ; 1395: 391-396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36527668

RESUMO

The current COVID-19 pandemic has shown us that the pulse oximeter is a key medical device for monitoring blood-oxygen levels non-invasively in patients with chronic or acute illness. It has also emphasised limitations in accuracy for individuals with darker skin pigmentation, calling for new methods to provide better measurements. The aim of our study is to identify the impact of skin pigmentation on pulse oximeter measurements. We also explored the benefits of a multi-wavelength approach with an induced change of arterial oxygen saturation. A total of 20 healthy volunteers were recruited. We used time domain diffuse reflectance spectroscopy (TDDRS) from a broad band light source, collecting spectra from the index finger along with three different pulse oximeters used simultaneously for monitoring purposes. Five acute hypoxic events were induced by administering 11% FiO2, produced by a Hypoxico altitude training system, for 120 sec through a face mask with a one-way valve. Our multi-wavelength approach revealed a correlation between the signature of skin pigmentation and the dynamic range of oxygen saturation measurements. Principal component analysis (PCA) showed separation between a range of different pigmented volunteers (PC1 = 56.00%) and oxygen saturation (PC2 = 22.99%). This emphasises the need to take into account skin pigmentation in oximeter measurements. This preliminary study serves to validate the need to better understand the impact of skin pigmentation absorption on optical readings in pulse oximeters. Multi-wavelength approaches have the potential to enable robust and accurate measurements across diverse populations.


Assuntos
COVID-19 , Pigmentação da Pele , Humanos , Projetos Piloto , Altitude , Pandemias , Oximetria/métodos , Hipóxia , Oxigênio
10.
Proc Natl Acad Sci U S A ; 116(11): 4834-4842, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30782834

RESUMO

Rapid, low-cost, species-specific diagnosis, based upon DNA testing, is becoming important in the treatment of patients with infectious diseases. Here, we demonstrate an innovation that uses origami to enable multiplexed, sensitive assays that rival polymerase chain reactions (PCR) laboratory assays and provide high-quality, fast precision diagnostics for malaria. The paper-based microfluidic technology proposed here combines vertical flow sample-processing steps, including paper folding for whole-blood sample preparation, with an isothermal amplification and a lateral flow detection, incorporating a simple visualization system. Studies were performed in village schools in Uganda with individual diagnoses being completed in <50 min (faster than the standard laboratory-based PCR). The tests, which enabled the diagnosis of malaria species in patients from a finger prick of whole blood, were both highly sensitive and specific, detecting malaria in 98% of infected individuals in a double-blind first-in-human study. Our method was more sensitive than other field-based, benchmark techniques, including optical microscopy and industry standard rapid immunodiagnostic tests, both performed by experienced local healthcare teams (which detected malaria in 86% and 83% of cases, respectively). All assays were independently validated using a real-time double-blinded reference PCR assay. We not only demonstrate that advanced, low-cost DNA-based sensors can be implemented in underserved communities at the point of need but also highlight the challenges associated with developing and implementing new diagnostic technologies in the field, without access to laboratories or infrastructure.


Assuntos
DNA de Protozoário/análise , Recursos em Saúde , Malária Falciparum/diagnóstico , Área Carente de Assistência Médica , Microfluídica/métodos , Técnicas de Diagnóstico Molecular/métodos , Papel , População Rural , Adolescente , Criança , Humanos , Malária Falciparum/sangue , Malária Falciparum/parasitologia , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes
11.
Am J Hum Genet ; 102(6): 1143-1157, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29805042

RESUMO

Non-syndromic cleft lip with or without cleft palate (NS-CL/P) is one of the most common human birth defects and is generally considered a complex trait. Despite numerous loci identified by genome-wide association studies, the effect sizes of common variants are relatively small, with much of the presumed genetic contribution remaining elusive. We report exome-sequencing results in 209 people from 72 multi-affected families with pedigree structures consistent with autosomal-dominant inheritance and variable penetrance. Herein, pathogenic variants are described in four genes encoding components of the p120-catenin complex (CTNND1, PLEKHA7, PLEKHA5) and an epithelial splicing regulator (ESRP2), in addition to the known CL/P-associated gene, CDH1, which encodes E-cadherin. The findings were also validated in a second cohort of 497 people with NS-CL/P, comprising small families and singletons with pathogenic variants in these genes identified in 14% of multi-affected families and 2% of the replication cohort of smaller families. Enriched expression of each gene/protein in human and mouse embryonic oro-palatal epithelia, demonstration of functional impact of CTNND1 and ESRP2 variants, and recapitulation of the CL/P spectrum in Ctnnd1 knockout mice support a causative role in CL/P pathogenesis. These data show that primary defects in regulators of epithelial cell adhesion are the most significant contributors to NS-CL/P identified to date and that inherited and de novo single gene variants explain a substantial proportion of NS-CL/P.


Assuntos
Caderinas/genética , Cateninas/genética , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Mutação/genética , Alelos , Sequência de Aminoácidos , Animais , Biotinilação , Epitélio/metabolismo , Epitélio/patologia , Feminino , Deleção de Genes , Humanos , Lactente , Recém-Nascido , Masculino , Camundongos , Palato/patologia , Linhagem , Síndrome , Sequenciamento do Exoma , delta Catenina
12.
Small ; 17(24): e2101114, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34013665

RESUMO

Spatially offset Raman spectroscopy is integrated with a fiber-coupled spatial heterodyne spectrometer to collect Raman spectra from deep within opaque or scattering materials. The method, named spatial heterodyne offset Raman spectroscopy generates a wavenumber-dependent spatial phase shift of the optical signal as a "spectral" image on a charge-coupled device detector. The image can be readily processed from the spatial domain using a single, simple, and "on-the-fly" Fourier transform to generate Raman spectra, in the frequency domain. By collecting all of the spatially offset Raman scattered photons that pass through the microscope's collection objective lens, the methodology gives an improvement in the Raman sensitivity by an order of magnitude. The instrumentation is both mechanically robust and "movement-free," which when coupled with the associated advantages of highly efficient signal collection and ease of data processing, enables rapid interfacial analysis of complex constructs based on established biomaterials models.


Assuntos
Materiais Biocompatíveis , Análise Espectral Raman , Fótons
13.
Mol Genet Metab ; 134(4): 323-329, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34844863

RESUMO

Sanfilippo D syndrome (mucopolysaccharidosis type IIID) is a lysosomal storage disorder caused by the deficiency of N-acetylglucosamine-6-sulfatase (GNS). A mouse model was generated by constitutive knockout of the Gns gene. We studied affected mice and controls at 12, 24, 36, and 48 weeks of age for neuropathological markers of disease in the somatosensory cortex, primary motor cortex, ventral posterior nuclei of the thalamus, striatum, hippocampus, and lateral and medial entorhinal cortex. We found significantly increased immunostaining for glial fibrillary associated protein (GFAP), CD68 (a marker of activated microglia), and lysosomal-associated membrane protein-1 (LAMP-1) in Sanfilippo D mice compared to controls at 12 weeks of age in all brain regions. Intergroup differences were marked for GFAP and CD68 staining, with levels in Sanfilippo D mice consistently above controls at all age groups. Intergroup differences in LAMP-1 staining were more pronounced in 12- and 24-week age groups compared to 36- and 48-week groups, as control animals showed some LAMP-1 staining at later timepoints in some brain regions. We also evaluated the somatosensory cortex, medial entorhinal cortex, reticular nucleus of the thalamus, medial amygdala, and hippocampal hilus for subunit c of mitochondrial ATP synthase (SCMAS). We found a progressive accumulation of SCMAS in most brain regions of Sanfilippo D mice compared to controls by 24 weeks of age. Cataloging the regional neuropathology of Sanfilippo D mice may aid in understanding the disease pathogenesis and designing preclinical studies to test brain-directed treatments.


Assuntos
Encéfalo/patologia , Mucopolissacaridose III/patologia , Animais , Feminino , Gliose/etiologia , Proteínas de Membrana Lisossomal/análise , Masculino , Camundongos , Microglia/fisiologia , ATPases Mitocondriais Próton-Translocadoras/análise , Mucopolissacaridose III/etiologia , Mucopolissacaridose III/metabolismo
14.
Mol Genet Metab ; 133(2): 185-192, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33839004

RESUMO

Mucopolysaccharidosis IIIB (MPS IIIB, Sanfilippo syndrome type B) is caused by a deficiency in α-N-acetylglucosaminidase (NAGLU) activity, which leads to the accumulation of heparan sulfate (HS). MPS IIIB causes progressive neurological decline, with affected patients having an expected lifespan of approximately 20 years. No effective treatment is available. Recent pre-clinical studies have shown that intracerebroventricular (ICV) ERT with a fusion protein of rhNAGLU-IGF2 is a feasible treatment for MPS IIIB in both canine and mouse models. In this study, we evaluated the biochemical efficacy of a single dose of rhNAGLU-IGF2 via ICV-ERT in brain and liver tissue from Naglu-/- neonatal mice. Twelve weeks after treatment, NAGLU activity levels in brain were 0.75-fold those of controls. HS and ß-hexosaminidase activity, which are elevated in MPS IIIB, decreased to normal levels. This effect persisted for at least 4 weeks after treatment. Elevated NAGLU and reduced ß-hexosaminidase activity levels were detected in liver; these effects persisted for up to 4 weeks after treatment. The overall therapeutic effects of single dose ICV-ERT with rhNAGLU-IGF2 in Naglu-/- neonatal mice were long-lasting. These results suggest a potential benefit of early treatment, followed by less-frequent ICV-ERT dosing, in patients diagnosed with MPS IIIB.


Assuntos
Acetilglucosaminidase/genética , Terapia de Reposição de Enzimas , Fator de Crescimento Insulin-Like II/genética , Mucopolissacaridose III/terapia , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Cães , Heparitina Sulfato/metabolismo , Humanos , Infusões Intraventriculares , Camundongos , Camundongos Knockout , Mucopolissacaridose III/enzimologia , Mucopolissacaridose III/genética , Mucopolissacaridose III/patologia , Doenças do Sistema Nervoso , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia
15.
Analyst ; 146(17): 5347-5356, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34323889

RESUMO

Human immunodeficiency virus (HIV) continues to be a major burden on public health globally with on-going increases in the number of new infections each year. Rapid and sensitive point-of-care tests allow timely interventions and are essential to control the spread of the disease. However the highly variable nature of the virus, resulting in the evolution of many subtypes and inter-subtype recombinants, poses important challenges for its diagnosis. Here we describe a variant-tolerant reverse-transcription RT-LAMP amplification of the virus's INT gene, providing a simple to use, rapid (<30 min) in vitro point-of-care diagnostic test with a limit of detection <18 copies/reaction. The assay was first validated in clinical studies of patient samples, using both established RT-LAMP and RT-qPCR assays for reference, with results showing that this new variant-tolerant HIV-1 RT-LAMP diagnostic test is highly sensitive without compromising its high specificity for HIV-1 subtypes. The diagnostic test was subsequently configured within an easy-to-read paper microfluidic lateral flow test and was validated clinically using patient samples, demonstrating its future potential for use in timely, effective, low cost HIV diagnostics in global regions where healthcare resources may be limited.


Assuntos
HIV-1 , HIV-1/genética , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Sistemas Automatizados de Assistência Junto ao Leito , Transcrição Reversa , Sensibilidade e Especificidade
16.
Proc Natl Acad Sci U S A ; 115(6): 1192-1197, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29358406

RESUMO

Cell response to matrix rigidity has been explained by the mechanical properties of the actin-talin-integrin-fibronectin clutch. Here the molecular clutch model is extended to account for cell interactions with purely viscous surfaces (i.e., without an elastic component). Supported lipid bilayers present an idealized and controllable system through which to study this concept. Using lipids of different diffusion coefficients, the mobility (i.e., surface viscosity) of the presented ligands (in this case RGD) was altered by an order of magnitude. Cell size and cytoskeletal organization were proportional to viscosity. Furthermore, there was a higher number of focal adhesions and a higher phosphorylation of FAK on less-mobile (more-viscous) surfaces. Actin retrograde flow, an indicator of the force exerted on surfaces, was also seen to be faster on more mobile surfaces. This has consequential effects on downstream molecules; the mechanosensitive YAP protein localized to the nucleus more on less-mobile (more-viscous) surfaces and differentiation of myoblast cells was enhanced on higher viscosity. This behavior was explained within the framework of the molecular clutch model, with lower viscosity leading to a low force loading rate, preventing the exposure of mechanosensitive proteins, and with a higher viscosity causing a higher force loading rate exposing these sites, activating downstream pathways. Consequently, the understanding of how viscosity (regardless of matrix stiffness) influences cell response adds a further tool to engineer materials that control cell behavior.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Bicamadas Lipídicas/química , Mioblastos/citologia , Fosfoproteínas/metabolismo , Actinas/metabolismo , Animais , Proteínas de Ciclo Celular , Linhagem Celular , Forma Celular , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fibronectinas/química , Adesões Focais , Bicamadas Lipídicas/metabolismo , Camundongos , Microscopia de Força Atômica , Mioblastos/metabolismo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Fosfatidilcolinas/química , Propriedades de Superfície , Viscosidade , Proteínas de Sinalização YAP
17.
Nano Lett ; 20(5): 3263-3270, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32233442

RESUMO

The ability to actuate liquids remains a fundamental challenge in smart microsystems, such as those for soft robotics, where devices often need to conform to either natural or three-dimensional solid shapes, in various orientations. Here, we propose a hierarchical nanotexturing of piezoelectric films as active microfluidic actuators, exploiting a unique combination of both topographical and chemical properties on flexible surfaces, while also introducing design concepts of shear hydrophobicity and tensile hydrophilicity. In doing so, we create nanostructured surfaces that are, at the same time, both slippery (low in-plane pinning) and sticky (high normal-to-plane liquid adhesion). By enabling fluid transportation on such arbitrarily shaped surfaces, we demonstrate efficient fluid motions on inclined, vertical, inverted, or even flexible geometries in three dimensions. Such surfaces can also be deformed and then reformed into their original shapes, thereby paving the way for advanced microfluidic applications.

18.
J Strength Cond Res ; 35(3): 833-840, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299388

RESUMO

ABSTRACT: Cooper, JJ, Johnson, M, Radcliffe, J, and Fisher, J. Optimal emotional profiles for peak performance in strength and conditioning. J Strength Cond Res 35(3): 833-840, 2021-This study investigated athletes' performance-related emotions and emotional profiles for optimal performance in strength and conditioning (S&C). It is suggested that the identification and control of emotions associated with successful and unsuccessful performances are essential for achieving peak psychological states and optimal performance in sports-related tasks. The individual zone of optimal functioning (IZOF) model outlines an idiographic and comprehensive conceptual framework of interrelated dimensions that describe the structure and dynamics of subjective emotional experiences and performance-related psychobiological states. With institutional ethics approval, 13 competitive elite athletes (male, n = 7; female, n = 6: mean age = 21.7 ± 4.0 years) completed IZOF-based emotion profiling, in which subjects were asked to recall their perceived best and worst S&C session, outlining emotions and intensity within 4 global emotional categories. A significant difference was evidenced between best ever and worst ever performance within positive functional emotions (p < 0.001, d = 3.63) and negative dysfunctional emotions (p < 0.001, d = 4.92). Initial findings suggest that perceived peak performance states within S&C are associated with a high intensity of positive functional emotions (confident, motivated, and energetic) and a low intensity of negative dysfunctional emotions (worn out, sluggish, annoyed, and discouraged). Although future research is necessary to fully understand this area, the present data suggest that to assist athletes in achieving perceived peak performance states within S&C, psychological skills and strategies should be informed and developed in collaboration with sport psychologists, with the aim of achieving an optimal emotional profile.


Assuntos
Emoções , Esportes , Logro , Adolescente , Adulto , Atletas , Feminino , Humanos , Masculino , Adulto Jovem
19.
Hum Mol Genet ; 27(6): 954-968, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29325092

RESUMO

Sandhoff disease (SD) is a rare inherited disorder caused by a deficiency of ß-hexosaminidase activity which is fatal because no effective treatment is available. A mouse model of Hexb deficiency reproduces the key pathognomonic features of SD patients with severe ubiquitous lysosomal dysfunction, GM2 accumulation, neuroinflammation and neurodegeneration, culminating in death at 4 months. Here, we show that a single intravenous neonatal administration of a self-complementary adeno-associated virus 9 vector (scAAV9) expressing the Hexb cDNA in SD mice is safe and sufficient to prevent disease development. Importantly, we demonstrate for the first time that this treatment results in a normal lifespan (over 700 days) and normalizes motor function assessed by a battery of behavioral tests, with scAAV9-treated SD mice being indistinguishable from wild-type littermates. Biochemical analyses in multiple tissues showed a significant increase in hexosaminidase A activity, which reached 10-15% of normal levels. AAV9 treatment was sufficient to prevent GM2 and GA2 storage almost completely in the cerebrum (less so in the cerebellum), as well as thalamic reactive gliosis and thalamocortical neuron loss in treated Hexb-/- mice. In summary, this study demonstrated a widespread protective effect throughout the entire CNS after a single intravenous administration of the scAAV9-Hexb vector to neonatal SD mice.


Assuntos
Hexosaminidase B/farmacologia , Doença de Sandhoff/tratamento farmacológico , Doença de Sandhoff/patologia , Administração Intravenosa , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Gangliosídeo G(M2)/metabolismo , Gangliosídeos/metabolismo , Hexosaminidase B/genética , Hexosaminidase B/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doença de Sandhoff/metabolismo
20.
Analyst ; 145(5): 1636-1640, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31932825

RESUMO

Generating a soluble and native-like trimeric envelope glycoprotein (Env) with high efficacy as an immunogen has been a major focus for developing an effective vaccine against HIV-1. The Env immunogen is a heavily glycosylated protein composed of 3 identical surface gp120 and gp41 subunits that form into a trimer of heterodimers (3 × 28 N-glycan sites). During Env immunogen production, endogenous furin works to cleave a hexa-arginine motif connecting the gp120 and gp41 subunits, which is needed to ensure proper protein folding and a native-like conformation of Env. Verification of the overall identity and proteolytic cleavage of Env is therefore important for HIV-1 vaccine development and product quality. Herein, we report the first work using LC-MS to (1) achieve fast and accurate intact mass measurement of Env after deglycosylation and (2) confidently identify the furin cleavage sites.


Assuntos
Cromatografia Líquida/métodos , Furina/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Proteína gp41 do Envelope de HIV/metabolismo , Multimerização Proteica , Espectrometria de Massas em Tandem/métodos , Motivos de Aminoácidos , Furina/química , Proteína gp120 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/química , Humanos , Ligação Proteica , Dobramento de Proteína
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