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1.
Ophthalmic Physiol Opt ; 44(4): 774-786, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38578134

RESUMEN

PURPOSE: To investigate gaze and behavioural metrics at different viewing distances with multifocal contact lenses (MFCLs), single vision contact lenses (SVCLs) and progressive addition lenses (PALs). METHODS: Fifteen presbyopic contact lens wearers participated over five separate study visits. At each visit, participants were randomly assigned to wear one of five refractive corrections: habitual PAL spectacles, delefilcon A (Alcon Inc.) MFCLs and three separate pairs of delefilcon A single vision lenses worn as distance, intermediate and near corrections. Participants wore a Pupil Core headset to record eye and head movements while performing three visual tasks: reading, visual search and scene observation. Data were investigated using linear regression and post-hoc testing. Parameters of interest included gaze (fixation duration, head movement) and behavioural (reading speed, reading accuracy, visual search time) metrics. RESULTS: Reading speed in SVCLs was significantly faster than in MFCLs and PAL spectacles (F = 16.3, p < 0.0001). Refractive correction worn did not influence visual search times (F = 0.16, p = 0.85). Fixation duration was significantly affected by the type of visual task (F = 60.2, p < 0.001), and an interaction effect was observed between viewing distance and refractive correction (F = 4.3, p = 0.002). There was significantly more horizontal and vertical head movement (F = 3.2, p = 0.01 and F = 3.3, p = 0.01, respectively) during visual search tasks when wearing PAL spectacles compared to SVCLs or MFCLs. CONCLUSION: This work showed that the type of refractive correction affects behavioural metrics such as reading speed and gaze behaviour by affecting horizontal and vertical head movements. The findings of this study suggest that under certain conditions, wearers of MFCLs make fewer head movements compared to PAL spectacles. Gaze behaviour metrics offer a new approach to compare and understand contact lens and spectacle performance, with potential applications including peripheral optical designs for myopia management.


Asunto(s)
Lentes de Contacto , Anteojos , Fijación Ocular , Presbiopía , Lectura , Refracción Ocular , Agudeza Visual , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimientos Oculares/fisiología , Fijación Ocular/fisiología , Movimientos de la Cabeza/fisiología , Presbiopía/fisiopatología , Presbiopía/terapia , Refracción Ocular/fisiología , Agudeza Visual/fisiología , Estudios Cruzados , Estudios Prospectivos
2.
Am J Physiol Regul Integr Comp Physiol ; 326(6): R515-R527, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38618911

RESUMEN

Inhibition of the bromodomain and extraterminal domain (BET) protein family is a potential strategy to prevent and treat diabetes; however, the clinical use of BET bromodomain inhibitors (BETis) is associated with adverse effects. Here, we explore a strategy for targeting BETis to ß cells by exploiting the high-zinc (Zn2+) concentration in ß cells relative to other cell types. We report the synthesis of a novel, Zn2+-chelating derivative of the pan-BETi (+)-JQ1, (+)-JQ1-DPA, in which (+)-JQ1 was conjugated to dipicolyl amine (DPA). As controls, we synthesized (+)-JQ1-DBA, a non-Zn2+-chelating derivative, and (-)-JQ1-DPA, an inactive enantiomer that chelates Zn2+. Molecular modeling and biophysical assays showed that (+)-JQ1-DPA and (+)-JQ1-DBA retain potent binding to BET bromodomains in vitro. Cellular assays demonstrated (+)-JQ1-DPA attenuated NF-ĸB target gene expression in ß cells stimulated with the proinflammatory cytokine interleukin 1ß. To assess ß-cell selectivity, we isolated islets from a mouse model that expresses green fluorescent protein in insulin-positive ß cells and mTomato in insulin-negative cells (non-ß cells). Surprisingly, Zn2+ chelation did not confer ß-cell selectivity as (+)-JQ1-DPA was equally effective in both ß and α cells; however, (+)-JQ1-DPA was less effective in macrophages, a nonendocrine islet cell type. Intriguingly, the non-Zn2+-chelating derivative (+)-JQ1-DBA displayed the opposite selectivity, with greater effect in macrophages compared with (+)-JQ1-DPA, suggesting potential as a macrophage-targeting molecule. These findings suggest that Zn2+-chelating small molecules confer endocrine cell selectivity rather than ß-cell selectivity in pancreatic islets and provide valuable insights and techniques to assess Zn2+ chelation as an approach to selectively target small molecules to pancreatic ß cells.NEW & NOTEWORTHY Inhibition of BET bromodomains is a novel potential strategy to prevent and treat diabetes mellitus. However, BET inhibitors have negative side effects. We synthesized a BET inhibitor expected to exploit the high zinc concentration in ß cells to accumulate in ß cells. We show our inhibitor targeted pancreatic endocrine cells; however, it was less effective in immune cells. A control inhibitor showed the opposite effect. These findings help us understand how to target specific cells in diabetes treatment.


Asunto(s)
Quelantes , Células Secretoras de Insulina , Zinc , Animales , Zinc/química , Zinc/farmacología , Zinc/metabolismo , Quelantes/farmacología , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Ratones , Factores de Transcripción/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Triazoles/farmacología , Triazoles/química , Humanos , Masculino , Azepinas/farmacología , Azepinas/química , Células Secretoras de Glucagón/efectos de los fármacos , Células Secretoras de Glucagón/metabolismo , Ratones Endogámicos C57BL , Proteínas que Contienen Bromodominio , Proteínas Nucleares
3.
Ophthalmic Physiol Opt ; 44(4): 704-717, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38546401

RESUMEN

PURPOSE: To investigate differences in key clinical parameters between asymptomatic and highly symptomatic soft contact lens (CL) wearers after 14 h of wear. METHODS: In this pilot investigation, Phase 1 identified asymptomatic (CLDEQ-8 score ≤ 7) and highly symptomatic (CLDEQ-8 score ≥ 20) subjects after fitting with nelfilcon A CLs. Phase 2 investigated the following over a single nelfilcon A CL-wearing day (14 ± 2 h): blinking characteristics, tear meniscus height (TMH), non-invasive tear break-up time (NIBUT), tear film osmolarity and eyelid margin staining. Parameters for the two groups were compared using linear mixed models and post-hoc testing. The relationship between comfort scores and the clinical parameters was also investigated. RESULTS: Overall, 161 and 42 subjects were enrolled into Phase 1 and 2, respectively. Twenty-five asymptomatic and 17 symptomatic subjects completed Phase 2. Lower eyelid TMH was decreased after 14 h in symptomatic compared with asymptomatic subjects (least square mean [LSM] difference -0.04 mm, 95% CI: -0.07, -0.01). Osmolarity was lower in symptomatic than in asymptomatic subjects at fitting (LSM difference -9.89, 95% CI: -18.91, -0.86). Upper eyelid margin staining was greater after 14 h in symptomatic than in asymptomatic subjects (LSM difference 0.53, 95% CI: 0.01, 1.05) and greater after 14 h than baseline in the symptomatic group (LSM difference 0.61, 95% CI: 0.16, 1.07). There was a significant relationship between comfort and upper eyelid margin staining (r = -0.40, 95% CI: -0.63, -0.11) and blink rate (r = -0.31, 95% CI: -0.57, -0.003). CONCLUSION: The potential parameters most effective in differentiating asymptomatic from symptomatic wearers were upper eyelid margin staining and lower TMH. The parameter with the strongest relationship to comfort was upper eyelid margin staining, where higher comfort scores were associated with lower levels of staining.


Asunto(s)
Parpadeo , Lentes de Contacto Hidrofílicos , Lágrimas , Humanos , Lentes de Contacto Hidrofílicos/efectos adversos , Masculino , Femenino , Adulto , Lágrimas/metabolismo , Lágrimas/fisiología , Proyectos Piloto , Parpadeo/fisiología , Adulto Joven , Concentración Osmolar , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/etiología , Síndromes de Ojo Seco/fisiopatología , Párpados
5.
ACS Chem Biol ; 19(1): 193-207, 2024 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-38159293

RESUMEN

S-Nitrosation is a cysteine post-translational modification fundamental to cellular signaling. This modification regulates protein function in numerous biological processes in the nervous, cardiovascular, and immune systems. Small molecule or protein nitrosothiols act as mediators of NO signaling by transferring the NO group (formally NO+) to a free thiol on a target protein through a transnitrosation reaction. The protein targets of specific transnitrosating agents and the extent and functional effects of S-nitrosation on these target proteins have been poorly characterized. S-nitroso-coenzyme A (CoA-SNO) was recently identified as a mediator of endogenous S-nitrosation. Here, we identified direct protein targets of CoA-SNO-mediated transnitrosation using a competitive chemical-proteomic approach that quantified the extent of modification on 789 cysteine residues in response to CoA-SNO. A subset of cysteines displayed high susceptibility to modification by CoA-SNO, including previously uncharacterized sites of S-nitrosation. We further validated and functionally characterized the functional effects of S-nitrosation on the protein targets phosphofructokinase (platelet type), ATP citrate synthase, and ornithine aminotransferase.


Asunto(s)
Coenzima A , Cisteína , S-Nitrosotioles , Nitrosación , Cisteína/química , Proteómica , Proteínas/metabolismo , S-Nitrosotioles/química , S-Nitrosotioles/metabolismo , Óxido Nítrico/metabolismo
6.
Nat Commun ; 14(1): 7000, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37919266

RESUMEN

Viral and host glycans represent an understudied aspect of host-pathogen interactions, despite potential implications for treatment of viral infections. This is due to lack of easily accessible tools for analyzing glycan function in a meaningful context. Here we generate a glycoengineered keratinocyte library delineating human glycosylation pathways to uncover roles of specific glycans at different stages of herpes simplex virus type 1 (HSV-1) infectious cycle. We show the importance of cellular glycosaminoglycans and glycosphingolipids for HSV-1 attachment, N-glycans for entry and spread, and O-glycans for propagation. While altered virion surface structures have minimal effects on the early interactions with wild type cells, mutation of specific O-glycosylation sites affects glycoprotein surface expression and function. In conclusion, the data demonstrates the importance of specific glycans in a clinically relevant human model of HSV-1 infection and highlights the utility of genetic engineering to elucidate the roles of specific viral and cellular carbohydrate structures.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Humanos , Herpesvirus Humano 1/genética , Herpes Simple/genética , Glicoproteínas/metabolismo , Queratinocitos/metabolismo , Polisacáridos/metabolismo , Proteínas del Envoltorio Viral/metabolismo
7.
Blood Adv ; 7(20): 6092-6107, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37406166

RESUMEN

Individuals with germ line variants associated with hereditary hematopoietic malignancies (HHMs) have a highly variable risk for leukemogenesis. Gaps in our understanding of premalignant states in HHMs have hampered efforts to design effective clinical surveillance programs, provide personalized preemptive treatments, and inform appropriate counseling for patients. We used the largest known comparative international cohort of germline RUNX1, GATA2, or DDX41 variant carriers without and with hematopoietic malignancies (HMs) to identify patterns of genetic drivers that are unique to each HHM syndrome before and after leukemogenesis. These patterns included striking heterogeneity in rates of early-onset clonal hematopoiesis (CH), with a high prevalence of CH in RUNX1 and GATA2 variant carriers who did not have malignancies (carriers-without HM). We observed a paucity of CH in DDX41 carriers-without HM. In RUNX1 carriers-without HM with CH, we detected variants in TET2, PHF6, and, most frequently, BCOR. These genes were recurrently mutated in RUNX1-driven malignancies, suggesting CH is a direct precursor to malignancy in RUNX1-driven HHMs. Leukemogenesis in RUNX1 and DDX41 carriers was often driven by second hits in RUNX1 and DDX41, respectively. This study may inform the development of HHM-specific clinical trials and gene-specific approaches to clinical monitoring. For example, trials investigating the potential benefits of monitoring DDX41 carriers-without HM for low-frequency second hits in DDX41 may now be beneficial. Similarly, trials monitoring carriers-without HM with RUNX1 germ line variants for the acquisition of somatic variants in BCOR, PHF6, and TET2 and second hits in RUNX1 are warranted.


Asunto(s)
Neoplasias Hematológicas , Leucemia , Humanos , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Neoplasias Hematológicas/genética , Mutación de Línea Germinal , ARN Helicasas DEAD-box/genética , Carcinogénesis , Células Germinativas , Factor de Transcripción GATA2/genética
8.
OTJR (Thorofare N J) ; 43(3): 531-539, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37122160

RESUMEN

COVID-19 catalyzed telehealth practice creating opportunities for clients and providers to discern best applications. Parent satisfaction with services supports partnership within therapy processes, potentially augmenting outcomes. We examined parent satisfaction levels and experiences with the telehealth approach of a parent coaching intervention for families of children with special health care needs (CSHCNs). We used a mixed-methods descriptive design. Fifteen parents completed the Telehealth Usability Questionnaire (TUQ) and a semistructured interview. We analyzed TUQ ratings using descriptive statistics, and we thematically analyzed participants' telehealth experiences. Parents found telehealth useful, easy to use, effective, reliable, and satisfactory. Parents described that telehealth addressed needs conveniently, enhanced parent-provider communication, and fostered shared parent involvement. Telehealth appears to be a satisfactory occupational therapy service delivery approach for parents of CSHCN. Findings build preliminary evidence for understanding for whom telehealth is well suited, supporting determination of relevant, fundable telehealth services.


Asunto(s)
COVID-19 , Tutoría , Telemedicina , Niño , Humanos , Padres , Satisfacción Personal
9.
J Genet Couns ; 32(5): 982-992, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37062897

RESUMEN

Families of children with developmental delays but no diagnosed genetic condition may benefit from connection to genetic systems of care. This work examines the role of occupational therapy as a space for families of pediatric patients to gain access to genetic services. Between September 2021 and February 2022, we interviewed 20 occupational therapists in New England who work primarily with pediatric patients. We transcribed the interviews and used a grounded theory approach to identify and code recurring themes. The data reveal several barriers to linking pediatric patients to genetic systems of care, including lack of insurance coverage, wait times for appointments and test results, hesitant primary care providers, and familial and cultural stigma of disability. We discuss the unique role of occupational therapists as professionals who spend substantial time with patients, often in their everyday environments, to bridge these barriers. We also address challenges associated with occupational therapists facilitating connections to genetics services, including their lack of specialized knowledge of genetics and barriers fully integrating with others on the medical team.


Asunto(s)
Personas con Discapacidad , Terapeutas Ocupacionales , Niño , Humanos , Pacientes , Servicios Genéticos , Derivación y Consulta
10.
Nat Med ; 29(1): 180-189, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36658419

RESUMEN

Pregnancy loss and perinatal death are devastating events for families. We assessed 'genomic autopsy' as an adjunct to standard autopsy for 200 families who had experienced fetal or newborn death, providing a definitive or candidate genetic diagnosis in 105 families. Our cohort provides evidence of severe atypical in utero presentations of known genetic disorders and identifies novel phenotypes and disease genes. Inheritance of 42% of definitive diagnoses were either autosomal recessive (30.8%), X-linked recessive (3.8%) or autosomal dominant (excluding de novos, 7.7%), with risk of recurrence in future pregnancies. We report that at least ten families (5%) used their diagnosis for preimplantation (5) or prenatal diagnosis (5) of 12 pregnancies. We emphasize the clinical importance of genomic investigations of pregnancy loss and perinatal death, with short turnaround times for diagnostic reporting and followed by systematic research follow-up investigations. This approach has the potential to enable accurate counseling for future pregnancies.


Asunto(s)
Aborto Espontáneo , Muerte Perinatal , Embarazo , Humanos , Femenino , Muerte Perinatal/etiología , Autopsia , Aborto Espontáneo/genética , Diagnóstico Prenatal , Genómica
11.
OTJR (Thorofare N J) ; 43(1): 24-34, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35574933

RESUMEN

Families provide foundational contexts in which most children develop and grow. For families of children with special health care needs (CSHCN), interdisciplinary supports can build family participation capacities, beyond individualistic child supports. This single-group pretest-posttest quasi-experimental study sought to determine the preliminary effects of the Healthy Families Flourish Program (HFFP), a telehealth occupation-based parent coaching intervention to promote participation, cohesion, adaptability, and communication for families of CSHCN. Eleven families, including 17 parents and 27 children, completed the 10-session intervention consisting of parent education and individualized coaching. Participants completed the Canadian Occupational Performance Measure, Goal Attainment Scaling, and the Family Adaptability and Cohesion Evaluation Scales pre-/post-intervention. Within-group comparisons showed improvements in family participation, cohesion, adaptability, and communication with Cohen's d effect sizes ranging from 0.55-3.32. Researchers found positive relationships between family participation and cohesion as well as participation and adaptability. Findings provide considerations for supporting families within socioecological contexts.


Asunto(s)
Tutoría , Telemedicina , Niño , Humanos , Canadá , Padres , Familia
12.
Am J Hum Genet ; 109(11): 1960-1973, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36332611

RESUMEN

Sharing genomic variant interpretations across laboratories promotes consistency in variant assertions. A landscape analysis of Australian clinical genetic-testing laboratories in 2017 identified that, despite the national-accreditation-body recommendations encouraging laboratories to submit genotypic data to clinical databases, fewer than 300 variants had been shared to the ClinVar public database. Consultations with Australian laboratories identified resource constraints limiting routine application of manual processes, consent issues, and differences in interpretation systems as barriers to sharing. This information was used to define key needs and solutions required to enable national sharing of variant interpretations. The Shariant platform, using both the GRCh37 and GRCh38 genome builds, was developed to enable ongoing sharing of variant interpretations and associated evidence between Australian clinical genetic-testing laboratories. Where possible, two-way automated sharing was implemented so that disruption to laboratory workflows would be minimized. Terms of use were developed through consultation and currently restrict access to Australian clinical genetic-testing laboratories. Shariant was designed to store and compare structured evidence, to promote and record resolution of inter-laboratory classification discrepancies, and to streamline the submission of variant assertions to ClinVar. As of December 2021, more than 14,000 largely prospectively curated variant records from 11 participating laboratories have been shared. Discrepant classifications have been identified for 11% (28/260) of variants submitted by more than one laboratory. We have demonstrated that co-design with clinical laboratories is vital to developing and implementing a national variant-interpretation sharing effort. This approach has improved inter-laboratory concordance and enabled opportunities to standardize interpretation practices.


Asunto(s)
Bases de Datos Genéticas , Laboratorios , Humanos , Variación Genética , Australia , Pruebas Genéticas
13.
Front Endocrinol (Lausanne) ; 13: 923925, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36176467

RESUMEN

Chronic inflammation of pancreatic islets is a key driver of ß-cell damage that can lead to autoreactivity and the eventual onset of autoimmune diabetes (T1D). In the islet, elevated levels of proinflammatory cytokines induce the transcription of the inducible nitric oxide synthase (iNOS) gene, NOS2, ultimately resulting in increased nitric oxide (NO). Excessive or prolonged exposure to NO causes ß-cell dysfunction and failure associated with defects in mitochondrial respiration. Recent studies showed that inhibition of the bromodomain and extraterminal domain (BET) family of proteins, a druggable class of epigenetic reader proteins, prevents the onset and progression of T1D in the non-obese diabetic mouse model. We hypothesized that BET proteins co-activate transcription of cytokine-induced inflammatory gene targets in ß-cells and that selective, chemotherapeutic inhibition of BET bromodomains could reduce such transcription. Here, we investigated the ability of BET bromodomain small molecule inhibitors to reduce the ß-cell response to the proinflammatory cytokine interleukin 1 beta (IL-1ß). BET bromodomain inhibition attenuated IL-1ß-induced transcription of the inflammatory mediator NOS2 and consequent iNOS protein and NO production. Reduced NOS2 transcription is consistent with inhibition of NF-κB facilitated by disrupting the interaction of a single BET family member, BRD4, with the NF-κB subunit, p65. Using recently reported selective inhibitors of the first and second BET bromodomains, inhibition of only the first bromodomain was necessary to reduce the interaction of BRD4 with p65 in ß-cells. Moreover, inhibition of the first bromodomain was sufficient to mitigate IL-1ß-driven decreases in mitochondrial oxygen consumption rates and ß-cell viability. By identifying a role for the interaction between BRD4 and p65 in controlling the response of ß-cells to proinflammatory cytokines, we provide mechanistic information on how BET bromodomain inhibition can decrease inflammation. These studies also support the potential therapeutic application of more selective BET bromodomain inhibitors in attenuating ß-cell inflammation.


Asunto(s)
Diabetes Mellitus Tipo 1 , Proteínas Nucleares , Animales , Citocinas/metabolismo , Inflamación/metabolismo , Mediadores de Inflamación , Interleucina-1beta , Ratones , FN-kappa B/metabolismo , Óxido Nítrico/efectos adversos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
15.
Cont Lens Anterior Eye ; 45(2): 101435, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33715968

RESUMEN

PURPOSE: To examine the annualised waste and end-of-life disposal options with two representative soft contact lens (CL) modalities. METHODS: The component parts of two representative soft CL modalities were catalogued, separated, weighed and inspected for material identification: somofilcon A soft CLs (clariti elite, CooperVision Inc.) used with multi-purpose solution (MPS) (All in one Light, CooperVision Inc.) and somofilcon A CLs (clariti 1 day, CooperVision Inc). Using a model that assumed compliant wear and care of CLs, the mass of material solid waste generated by CL use over a year was calculated. Disposal options were explored using household and specialist recycling streams in order to develop recommendations for responsible disposal of CL waste. RESULTS: Full-time daily disposable (DD) CL wear generates 1.06 kg of waste annually compared to 0.83 kg generated by reusable-monthly replacement daily wear ('reusable') CLs. Plastic was the dominant material in both modalities. With full-time use of DD CLs, 64% of waste by mass was plastic blister trays. For full-time use of reusable CLs, where figures from lens and MPS packaging are combined, plastics accounted for 67% of waste by mass. MPS bottles alone made up almost half the waste (45%) associated with full-time reusable CL wear. CONCLUSION: Full-time DD wear generates 27% more waste annually than full-time reusable lens wear. Reusable CL wearers can recycle 78% of waste at home. DD lens wearers have access to recycling options that allow them to recycle 100% of CL related waste. Full-time CL lens wear represents just 0.20-0.26% of the 412 kg of household waste generated per person, per year in the United Kingdom. Worn CLs should never be disposed of down the sink or lavatory. CL wearers should be aware of responsible end-of-life recycling and disposal options for all CL waste.


Asunto(s)
Lentes de Contacto Hidrofílicos , Cristalino , Muerte , Equipos Desechables , Humanos , Plásticos , Reino Unido
16.
Front Physiol ; 12: 763417, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34899389

RESUMEN

Increased sirtuin deacylase activity is correlated with increased lifespan and healthspan in eukaryotes. Conversely, decreased sirtuin deacylase activity is correlated with increased susceptibility to aging-related diseases. However, the mechanisms leading to decreased sirtuin activity during aging are poorly understood. Recent work has shown that oxidative post-translational modification by reactive oxygen (ROS) or nitrogen (RNS) species results in inhibition of sirtuin deacylase activity through cysteine nitrosation, glutathionylation, sulfenylation, and sulfhydration as well as tyrosine nitration. The prevalence of ROS/RNS (e.g., nitric oxide, S-nitrosoglutathione, hydrogen peroxide, oxidized glutathione, and peroxynitrite) is increased during inflammation and as a result of electron transport chain dysfunction. With age, cellular production of ROS/RNS increases; thus, cellular oxidants may serve as a causal link between loss of sirtuin activity and aging-related disease development. Therefore, the prevention of inhibitory oxidative modification may represent a novel means to increase sirtuin activity during aging. In this review, we explore the role of cellular oxidants in inhibiting individual sirtuin human isoform deacylase activity and clarify the relevance of ROS/RNS as regulatory molecules of sirtuin deacylase activity in the context of health and disease.

17.
Front Microbiol ; 12: 703177, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34381430

RESUMEN

Using acidophilic bacteria to catalyze the reductive dissolution of oxidized minerals is an innovative process that facilitates the extraction of valuable base metals (principally cobalt and nickel) from limonites, which are otherwise often regarded as waste products of laterite mining. The most appropriate conditions required to optimize reductive mineral dissolution are unresolved, and the current work has reassessed the roles of Acidithiobacillus spp. in this process and identified novel facets. Aerobic bio-oxidation of zero-valent sulfur (ZVS) can generate sufficient acidity to counterbalance that consumed by the dissolution of oxidized iron and manganese minerals but precludes the development of low redox potentials that accelerate the reductive process, and although anaerobic oxidation of sulfur by iron-reducing species can achieve this, less acid is generated. Limited reduction of soluble iron (III) occurs in pure cultures of Acidithiobacillus spp. (Acidithiobacillus thiooxidans and Acidithiobacillus caldus) that do not grow by iron respiration. This phenomenon ("latent iron reduction") was observed in aerated cultures and bioreactors and was independent of electron donor used (ZVS or hydrogen). Sufficient ferrous iron was generated in the presence of sterilized hydrophilic sulfur (bio-ZVS) to promote the effective reductive dissolution of Mn (IV) minerals in limonite and the solubilization of cobalt in the absence of viable acidophiles.

18.
Hum Mutat ; 42(11): 1399-1421, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34387894

RESUMEN

GATA2 deficiency syndrome (G2DS) is a rare autosomal dominant genetic disease predisposing to a range of symptoms, of which myeloid malignancy and immunodeficiency including recurrent infections are most common. In the last decade since it was first reported, there have been over 480 individuals identified carrying a pathogenic or likely pathogenic germline GATA2 variant with symptoms of G2DS, with 240 of these confirmed to be familial and 24 de novo. For those that develop myeloid malignancy (75% of all carriers with G2DS disease symptoms), the median age of onset is 17 years (range 0-78 years) and myelodysplastic syndrome is the first diagnosis in 75% of these cases with acute myeloid leukemia in a further 9%. All variant types appear to predispose to myeloid malignancy and immunodeficiency. Apart from lymphedema in which haploinsufficiency seems necessary, the mutational requirements of the other less common G2DS phenotypes is still unclear. These predominantly loss-of-function variants impact GATA2 expression and function in numerous ways including perturbations to DNA binding, protein structure, protein:protein interactions, and gene transcription, splicing, and expression. In this review, we provide the first expert-curated ACMG/AMP classification with codes of published variants compatible for use in clinical or diagnostic settings.


Asunto(s)
Deficiencia GATA2/genética , Factor de Transcripción GATA2/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios de Cohortes , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Adulto Joven
20.
BMC Med Genomics ; 14(1): 64, 2021 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-33639934

RESUMEN

BACKGROUND: Periventricular nodular heterotopia (PNH) is a malformation of cortical development characterized by nodules of abnormally migrated neurons. The cause of posteriorly placed PNH is not well characterised and we present a case that provides insights into the cause of posterior PNH. CASE PRESENTATION: We report a fetus with extensive posterior PNH in association with biallelic variants in LAMC3. LAMC3 mutations have previously been shown to cause polymicrogyria and pachygyria in the occipital cortex, but not PNH. The occipital location of PNH in our case and the proposed function of LAMC3 in cortical development suggest that the identified LAMC3 variants may be causal of PNH in this fetus. CONCLUSION: We hypothesise that this finding extends the cortical phenotype associated with LAMC3 and provides valuable insight into genetic cause of posterior PNH.


Asunto(s)
Heterotopia Nodular Periventricular , Encéfalo , Imagen por Resonancia Magnética
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