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1.
BMJ Case Rep ; 17(8)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39117364

RESUMO

A 22-kg female in early childhood with a history of reactive airway disease presented to a paediatric emergency department with acute shortness of breath, tachypnoea and wheezing. Despite treatment with albuterol and corticosteroids, her bronchospasm persisted, prompting the administration of terbutaline. The patient received 220 mcg (10 mcg/kg) terbutaline intravenously, followed immediately by an inadvertent supratherapeutic intravenous dose of 10 000 mcg (454.5 mcg/kg). The patient's laboratory results obtained minutes after the medication error were notable for: potassium, 3.1 mmol/L, lactate, 2.6 mmol/L and troponin I, 0.30 ng/mL (normal <0.03 ng/mL). Over the next 48 hours, serial serum troponin values decreased. The patient was discharged home approximately 72 hours after the initial presentation and she remained well based on follow-up calls over the next several months. Given the timing and trend of troponin concentrations, we do not believe the terbutaline overdose to be responsible for the myocardial injury.


Assuntos
Overdose de Drogas , Terbutalina , Humanos , Terbutalina/administração & dosagem , Feminino , Broncodilatadores/administração & dosagem , Administração Intravenosa , Troponina I/sangue , Pré-Escolar
2.
J Urol ; : 101097JU0000000000004147, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093847

RESUMO

PURPOSE: Multiple factors are thought to give rise to common, recurrent kidney stone disease, but for monogenic stone disorders a firm diagnosis is possible through genetic testing. The autosomal recessive primary hyperoxalurias (PH) are rare forms of monogenic kidney stone disease. All 3 types of PH are caused by inborn errors of glyoxylate metabolism in the liver, leading to hepatic oxalate overproduction and excessive renal urinary oxalate excretion. These conditions are characterized by kidney stones, nephrocalcinosis, progressive chronic kidney disease, and kidney failure. Systemic oxalosis, the extra-renal deposition of oxalate resulting in severe morbidity and mortality, occurs in chronic kidney disease when oxalate clearance by the kidneys declines. Novel small interfering RNA-based therapeutics targeting the liver to reduce urinary oxalate excretion have been approved, introducing precision medicine to treat primary hyperoxaluria type 1. The goal of this narrative review is to address the benefits and practicalities of genetic testing for suspected monogenic kidney stone disease and the critical roles of a multidisciplinary team. MATERIALS AND METHODS: We collated our procedures, education, training, and workflows to help other clinicians integrate genetic assessment into their diagnostic routines. RESULTS: In our experience, increased access to genetic testing facilitates early detection of PH and other monogenic causes of kidney stone disease so that individualized care can be instituted promptly. CONCLUSIONS: Alongside biochemical assessments, more widespread genetic testing may ensure more timely diagnoses so that patients with suspected monogenic kidney stone disease gain access to an expanded range of services and enrollment in clinical trials and registries.

3.
Sci Total Environ ; : 175067, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39111421

RESUMO

Phytoplanktonic overgrowth, which characterizes the eutrophication or trophic status of surface water bodies, threatens ecosystems and public health. Quantitative polymerase chain reaction (qPCR) is promising for assessing the abundance and community composition of phytoplankton. However, applications of qPCR to indicate eutrophication and trophic status, especially in lotic systems, have yet to be comprehensively evaluated. For the first time, this study correlates qPCR-based phytoplankton abundance with chlorophyll a (the most widely used indicator of eutrophication and trophic status) in multiple freshwater rivers. From early summer to late fall in 2017, 2018, and 2019, we evaluated phytoplankton, chlorophyll a, pheophytin a, and the Trophic Level Index (TLI) in twelve large freshwater rivers in three regions (western, midcontinent, and eastern) in the United States. Chlorophyll a concentration had positive allometric correlations with qPCR-based phytoplankton abundance (adjusted R2 = 0.5437, p-value <0.001), pheophytin a concentration (adjusted R2 = 0.3378, p-value <0.001), and TLI (adjusted R2 = 0.4789, p-value <0.001). Thus, a greater phytoplankton abundance suggests a higher trophic status. This work also presents the numerical values of qPCR-based phytoplankton abundance defining the boundaries among trophic statuses (e.g., oligotrophic, mesotrophic, and eutrophic) of freshwater rivers. The sampling sites in the midcontinent rivers were more eutrophic because they had significantly higher chlorophyll a concentrations, pheophytin a concentrations, and TLI values than in the western and eastern rivers. The higher phytoplankton abundance at the midcontinent sites confirmed their higher trophic status. By linking qPCR-based phytoplankton abundance to chlorophyll a, this study demonstrates that qPCR is a promising avenue to investigate the population dynamics of phytoplankton and the trophic status (or eutrophication) of freshwater rivers.

4.
Am J Obstet Gynecol ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39111516

RESUMO

OBJECTIVE: Financial strain and unmet social needs are associated with greater risk for lower urinary tract symptoms. Little research has examined financial strain and unmet social needs in relation to the more holistic concept of bladder health. This study utilizes baseline data from RISE FOR HEALTH: A U.S. Study of Bladder Health to examine whether financial strain, unmet social needs, and meeting specific federal poverty level threshold levels are associated with lower urinary tract symptoms and poorer perceived bladder health, well-being, and function. STUDY DESIGN: Participants were 18 years or older, born female or currently identified as a woman, and from the civilian, noninstitutionalized population residing in 50 counties in the United States that included or surrounded nine recruitment centers. Data were collected through mailed or internet-based surveys. To address research questions, the 10-item Lower Urinary Tract Dysfunction Research Network Symptom Index and selected Prevention of Lower Urinary Tract Symptoms Research Consortium bladder health scores were separately regressed on each financial strain, unmet social need, and federal poverty level variable, using linear regression adjusting for covariates (age, race/ethnicity, education, and vaginal parity) and robust variance estimation for confidence intervals. Participants with no missing data for a given analysis were included (range of n=2,564 to 3,170). In separate sensitivity analyses, body mass index, hypertension, and diabetes were added as covariates and missing data were imputed. RESULTS: The mean age of participants was 51.5 years (standard deviation=18.4). Not having enough money to make ends meet, housing insecurity, food insecurity, unreliable transportation, and percent federal poverty levels of 300% or less were consistently associated with more reported lower urinary tract symptoms and poorer perceived bladder health. For example, compared to food secure participants, women who worried that their food would run out at the end of the month had a Lower Urinary Tract Dysfunction Research Network - Symptom Index score that was 3.4 points higher (95% CI: 2.5, 4.3), on average. They also had lower mean scores across different bladder health measures, each assessed using a 100-point scale: global bladder health (-8.2, 95% CI: -10.8,-5.7), frequency (-10.2, 95% CI: -13.8,-6.7), sensation (-11.6, 95% CI: -15.1,-8.2), continence (-13.3, 95% CI: -16.7,-9.9), and emotional impact of bladder health status (-13.2, 95% CI: -16.5,-9.9). Across analyses, associations largely remained significant after additional adjustment for body mass index, hypertension, and diabetes. The pattern of results when imputing missing data was similar to that observed with complete case analysis; all significant associations remained significant with imputation. CONCLUSION: Financial strain and unmet social needs are associated with worse LUTS and poorer bladder health. Longitudinal research is needed to examine whether financial strain and unmet social needs influence the development, maintenance, and worsening of lower urinary tract symptoms; different mechanisms by which financial strain and unmet social needs may impact symptoms; and the degree to which symptoms contribute to financial strain. If supported by etiologic research, prevention research can be implemented to determine whether the amelioration of financial strain and social needs, including enhanced access to preventative care, may promote bladder health across the life course.

5.
Aging Cell ; : e14295, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102872

RESUMO

Senescence is an important cellular program occurring in development, tissue repair, cancer, and aging. Increased senescence is also associated with disease states, including obesity and Type 2 diabetes (T2D). Characterizing and quantifying senescent cells at a single cell level has been challenging and particularly difficult in large primary cells, such as human adipocytes. In this study, we present a novel approach that utilizes reflected light for accurate senescence-associated beta-galactosidase (SABG) staining measurements, which can be integrated with immunofluorescence and is compatible with primary mature adipocytes from both human and mouse, as well as with differentiated 3T3-L1 cells. This technique provides a more comprehensive classification of a cell's senescent state by incorporating multiple criteria, including robust sample-specific pH controls. By leveraging the precision of confocal microscopy to detect X-gal crystals using reflected light, we achieved superior sensitivity over traditional brightfield techniques. This strategy allows for the capture of all X-gal precipitates in SABG-stained samples, revealing diverse X-gal staining patterns and improved detection sensitivity. Additionally, we demonstrate that reflected light outperforms western blot analysis for the detection and quantification of senescence in mature human adipocytes, as it offers a more accurate representation of SABG activity. This detection strategy enables a more thorough investigation of senescent cell characteristics and specifically a deeper look at the relationship between adipocyte senescence and obesity associated disorders, such as T2D.

6.
JACC Adv ; 3(7): 100995, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39129999

RESUMO

Background: Traditionally, low cardiac output has been considered the primary hemodynamic driver of renal function and injury. Adult data suggest that central venous pressure (CVP) is a more important factor. Objectives: The authors hypothesized that in children with cardiovascular disease, higher CVP predicts lower estimated glomerular filtration rate (eGFR) and worsening renal function (WRF). Methods: We performed a single-center cohort study of patients aged 3 months to 21 years with biventricular circulation undergoing cardiac catheterization. Pearson's correlation and linear and Cox regression analyses were performed to determine associations with eGFR at the time of catheterization and WFR within 180 days after catheterization. Results: 312 patients had median age 7.9 years (IQR: 2.3 to 14.5 years), median eGFR 97 mL/min/1.73 m2 (IQR: 81-118 mL/min/1.73 m2), median CVP 7 mm Hg (IQR: 5-9 mm Hg), and median cardiac index 3.7 mL/min/m2 (IQR: 2.9-4.6 mL/min/m2). Nearly half (48%) were transplant recipients. In multivariable analysis, CVP was independently associated with eGFR (ß = -2.65; 95% CI: -4.02, -1.28; P < 0.001), as was being a transplant recipient (ß = -10.20; 95% CI: -17.74, -2.65; P = 0.008), while cardiac index was not. Fifty-one patients (16%) developed WRF. In a proportional hazards model adjusting for cardiac index, only higher CVP (HR: 1.10; 95% CI: 1.04-1.17; P = 0.002) and greater contrast volume by weight (HR: 1.05; 95% CI: 1.01-1.10; P = 0.021) predicted WRF. CVP ≥7 mm Hg likewise predicted WRF (HR: 2.57; 95% CI: 1.29-5.12; P = 0.007). Conclusions: Among children with a spectrum of cardiovascular disease, higher CVP is associated with lower eGFR and development of WRF, independent of cardiac index.

8.
Cell Rep ; 43(8): 114503, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39018245

RESUMO

Synaptic plasticities, such as long-term potentiation (LTP) and depression (LTD), tune synaptic efficacy and are essential for learning and memory. Current studies of synaptic plasticity in humans are limited by a lack of adequate human models. Here, we modeled the thalamocortical system by fusing human induced pluripotent stem cell-derived thalamic and cortical organoids. Single-nucleus RNA sequencing revealed that >80% of cells in thalamic organoids were glutamatergic neurons. When fused to form thalamocortical assembloids, thalamic and cortical organoids formed reciprocal long-range axonal projections and reciprocal synapses detectable by light and electron microscopy, respectively. Using whole-cell patch-clamp electrophysiology and two-photon imaging, we characterized glutamatergic synaptic transmission. Thalamocortical and corticothalamic synapses displayed short-term plasticity analogous to that in animal models. LTP and LTD were reliably induced at both synapses; however, their mechanisms differed from those previously described in rodents. Thus, thalamocortical assembloids provide a model system for exploring synaptic plasticity in human circuits.

9.
Biochem J ; 481(13): 865-881, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958472

RESUMO

Filamin A is an essential protein in the cell cytoskeleton because of its actin binding properties and unique homodimer rod-shaped structure, which organises actin into three-dimensional orthogonal networks imperative to cell motility, spreading and adhesion. Filamin A is subject to extensive posttranslational modification (PTM) which serves to co-ordinate cellular architecture and to modulate its large protein-protein interaction network which is key to the protein's role as a cellular signalling hub. Characterised PTMs include phosphorylation, irreversible cleavage, ubiquitin mediated degradation, hydroxylation and O-GlcNAcylation, with preliminary evidence of tyrosylation, carbonylation and acetylation. Each modification and its relation to filamin A function will be described here. These modifications are often aberrantly applied in a range of diseases including, but not limited to, cancer, cardiovascular disease and neurological disease and we discuss the concept of target specific PTMs with novel therapeutic modalities. In summary, our review represents a topical 'one-stop-shop' that enables understanding of filamin A function in cell homeostasis and provides insight into how a variety of modifications add an extra level of Filamin A control.


Assuntos
Filaminas , Processamento de Proteína Pós-Traducional , Filaminas/metabolismo , Humanos , Animais , Fosforilação , Neoplasias/metabolismo
10.
ACS Omega ; 9(29): 32097-32106, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39072092

RESUMO

Pentaerythritol tetranitrate (PETN) has been used extensively in commercial detonators and other explosive applications for many decades. Here, we show the results of a comprehensive 1.5 year aging study of PETN in commercial detonators, addressing batch-to-batch variations, surface area changes, and comparisons of aged loose powders side-by-side with identically aged detonators. Function time analysis of the aged detonators has also been provided and discussed in the context of powder aging. This large-scale, statistically relevant study addresses long-standing questions on PETN aging without the complications from making comparisons between multiple batches of material. We have evaluated the aging time required to reach the maximum measured amount of PETN coarsening and estimated an activation barrier of ∼123 kJ mol-1, which is higher than literature values reported by Gee et al. It is possible that this discrepancy is due to the fact that that this study cannot quantify the relative contributions of surface diffusion versus sublimation processes. At the lower temperatures of 50 and 60 °C, we assume that surface diffusion dominates over sublimation processes, even at longer aging times. At the higher temperature of 75 °C, we assume that both surface diffusion and sublimation contribute at the early time points, which are included in the Arrhenius analysis for coarsening.

11.
Brain Behav Immun ; 121: 229-243, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39067620

RESUMO

Prebiotic galactooligosaccharides (GOS) reduce anxiety-like behaviors in mice and humans. However, the biological pathways behind these behavioral changes are not well understood. To begin to study these pathways, we utilized C57BL/6 mice that were fed a standard diet with or without GOS supplementation for 3 weeks prior to testing on the open field. After behavioral testing, colonic contents and serum were collected for bacteriome (16S rRNA gene sequencing, colonic contents only) and metabolome (UPLC-MS, colonic contents and serum data) analyses. As expected, GOS significantly reduced anxiety-like behavior (i.e., increased time in the center) and decreased cytokine gene expression (Tnfa and Ccl2) in the prefrontal cortex. Notably, time in the center of the open field was significantly correlated with serum methyl-indole-3-acetic acid (methyl-IAA). This metabolite is a methylated form of indole-3-acetic acid (IAA) that is derived from bacterial metabolism of tryptophan. Sequencing analyses showed that GOS significantly increased Lachnospiraceae UCG006 and Akkermansia; these taxa are known to metabolize both GOS and tryptophan. To determine the extent to which methyl-IAA can affect anxiety-like behavior, mice were intraperitoneally injected with methyl-IAA. Mice given methyl-IAA had a reduction in anxiety-like behavior in the open field, along with lower Tnfa in the prefrontal cortex. Methyl-IAA was also found to reduce TNF-α (as well as CCL2) production by LPS-stimulated BV2 microglia. Together, these data support a novel pathway through which GOS reduces anxiety-like behaviors in mice and suggests that the bacterial metabolite methyl-IAA reduces microglial cytokine and chemokine production, which in turn reduces anxiety-like behavior.

12.
Chem Commun (Camb) ; 60(64): 8399-8402, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39028006

RESUMO

Here we report the synthesis and characterization of diiron complexes containing triaryl N4 and N2S2 ligands derived from o-phenylenediamine. The complexes display significant differences in Fe-Fe distances and magnetic properties that depend on the identity of the flanking NMe2 and SMe donor groups.

13.
Org Biomol Chem ; 22(31): 6308-6320, 2024 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-39037740

RESUMO

Amide bonds are one of the most prevalent phenomena in nature and are utilized frequently in drug and material design. However, forming amide bonds is not always efficient or high yielding, particularly when the amine used to conjugate to a carboxylic acid is a weak nucleophile. This limitation precludes many useful amino compounds from participating in conjugation reactions to form amides. A particularly valuable amino compound, which is also a very weak nucleophile, is the amino porphyrin, valued for its role as a photosensitizer, fluorescent agent, catalyst, or, upon metalation, even a very efficient contrast agent for magnetic resonance imaging (MRI). In this work, we propose fast and high-yield coupling of an unreactive amine - the amino porphyrin - to carboxylic acid via isothiocyanate conjugation. Reactions can be achieved in one step at room temperature in one hour, achieving quantitative conversion and near perfect selectivity. Both metalated and unmetalated porphyrin, as well as fluorescein isothiocyanate (FITC), demonstrated efficient conjugation. To illustrate the value of the proposed method, we created a new blood-pool MRI contrast agent that reversibly binds to serum albumin. This new blood-pool agent, known as MITC-Deox (MRI isothiocyanate that links with deoxycholic acid), substantially reduced T1 relaxation times in blood vessels in mice, remained stable for 1 hour, cleared from blood by 24 hours, and was eliminated from the body after 4 days. The proposed method for efficient amide formation is a superior alternative to existing coupling methods, opening a door to novel synthesis of MRI contrast agents and beyond.


Assuntos
Amidas , Meios de Contraste , Porfirinas , Porfirinas/química , Porfirinas/síntese química , Amidas/química , Amidas/síntese química , Animais , Camundongos , Meios de Contraste/química , Meios de Contraste/síntese química , Imageamento por Ressonância Magnética , Estrutura Molecular , Isotiocianatos/química , Fluoresceína-5-Isotiocianato/química
14.
Biochem Biophys Rep ; 39: 101765, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39040543

RESUMO

Primary Hyperoxaluria Type 3 (PH3) results from 4-hydroxy-2-oxoglutarate (HOG) aldolase (HOGA) deficiency, which causes an increase in endogenous oxalate synthesis leading to calcium oxalate kidney stone disease. The mechanisms underlying HOG metabolism and increased oxalate synthesis in PH3 are not well understood. We used a Hoga1 knock-out mouse model of PH3 to investigate two aspects of HOG metabolism: reduction to dihydroxyglutarate (DHG), a pathway that may limit oxalate synthesis in PH3, and metabolism to glyoxylate, which is a direct precursor to oxalate. The metabolism of HOG to DHG was highest in liver and kidney cortical tissue, enhanced in the cytosolic compartment of the liver, and preferred NADPH as a cofactor. In the absence of HOGA, HOG to glyoxylate aldolase activity was highest in liver mitoplasts, with no activity present in brain tissue lysates. These findings will assist in the identification of enzymes responsible for the metabolism of HOG to DHG and glyoxylate, which may lead to novel therapeutic approaches to limit oxalate synthesis in those afflicted with PH3.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38981690

RESUMO

Intramedullary nails are specialized metal rods inserted into the medullary cavity of a fractured bone and secured to reduce load on the fracture site, provide stability, and permit healing. The purpose of this review is to highlight the biomechanics of orthopaedic intramedullary nailing, as well as discuss the biomechanical considerations that have shaped implant design and fixation technique in veterinary and human medicine. Relevant studies were included from the PubMed database and Google Scholar for discussion on the basic science and nail design of intramedullary nails. Implant design and implementation continues to progress, with new innovative designs currently under investigation. A lack of consensus remains on the superior implant material. Recent studies, particularly in human populations, have supported the use of reaming based on reoperation rates, nonunion rates, and dynamization. Design modifications, such as the expandable intramedullary nails and angle-stable interlocking designs, have been investigated as methods of improving cortical contact and resisting torsional stress. Intramedullary nailing is a valuable stabilization technique for long bone fractures across a variety of species. The technology continues to undergo design improvements in both veterinary and human medicine.

16.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037303

RESUMO

There are few techniques available for chemists to obtain time-to-explosion data with known temperature inputs at the early stages of the design and synthesis of new explosives. In the 1960s, a technique was developed to rapidly heat milligram-quantities of confined explosives to ∼1000 K on microsecond timescales. Wenograd [Trans. Faraday Soc. 57, 1612 (1961)] loaded explosives inside stainless steel hypodermic needles, connected them to a fireset and rapidly discharged a capacitor through the steel. He obtained the temperature by measuring the needle resistance in a Wheatstone bridge arrangement and the time to explosion from a needle rupture. However, owing to the narrow-gauge needles used in the original research, the experiment was only possible with melt-castable explosives; it was never replicated, and modern diagnostics are now available with advances beyond the 1960s. Here, we report the development of the High Explosives Initiation Time (HEIT) test, which utilizes a 250 J pulsed power system to heat the needles. This work extends the Wenograd approach by using optical diagnostics, computational modeling, and advanced techniques to measure needle resistance and needle rupture. Preliminary rate information for pentaerythritol tetranitrate (PETN) will be presented.

17.
Pediatr Obes ; 19(8): e13143, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38886982

RESUMO

BACKGROUND: Anti-obesity medications (AOMs) are promising lifestyle modification (LSM) adjuncts for obesity treatment, and phentermine is commonly prescribed in paediatric weight management clinics. Determining 'real-world' AOM effectiveness and characteristics predicting response is important. OBJECTIVES: We sought to describe phentermine plus LSM effectiveness and identify baseline characteristics predicting response. METHODS: This was a retrospective cohort study among youth seen in a US academic-based weight management clinic from 2012 to 2020. Baseline characteristics (e.g., body mass index (BMI), liver transaminases, eating-related behaviours) and outcomes (%BMI of 95th percentile (%BMIp95), BMI, %BMI change, weight) were determined through electronic health records and intake surveys. RESULTS: Among 91 youth prescribed phentermine plus LSM over 8 years (mean %BMIp95 150%), %BMIp95 was statistically significantly reduced at 1.5, 3, 6 and 12 months (peak reduction 10.9 percentage points at 6 months; p < 0.001). Considering multiple comparisons, the presence of baseline elevated alanine aminotransferase was associated with statistically significant smaller 1.5-month %BMIp95 reductions (p = 0.001) and higher food responsiveness with smaller 3- (p = 0.001) and 6-month (p < 0.001) reductions. CONCLUSIONS: Phentermine plus LSM reduced %BMIp95 among youth in a weight management clinic, and baseline characteristics may help determine those more or less likely to respond. Prospective studies are needed to further characterize effectiveness and confirm response predictors.


Assuntos
Obesidade Infantil , Fentermina , Redução de Peso , Humanos , Feminino , Masculino , Estudos Retrospectivos , Obesidade Infantil/epidemiologia , Obesidade Infantil/terapia , Fentermina/uso terapêutico , Criança , Adolescente , Fármacos Antiobesidade/uso terapêutico , Resultado do Tratamento , Índice de Massa Corporal , Comportamento de Redução do Risco , Estilo de Vida
18.
Nucleic Acids Res ; 52(12): 6733-6747, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38828787

RESUMO

Adenosine Deaminases Acting on RNA (ADARs) are enzymes that catalyze the conversion of adenosine to inosine in RNA duplexes. These enzymes can be harnessed to correct disease-causing G-to-A mutations in the transcriptome because inosine is translated as guanosine. Guide RNAs (gRNAs) can be used to direct the ADAR reaction to specific sites. Chemical modification of ADAR guide strands is required to facilitate delivery, increase metabolic stability, and increase the efficiency and selectivity of the editing reaction. Here, we show the ADAR reaction is highly sensitive to ribose modifications (e.g. 4'-C-methylation and Locked Nucleic Acid (LNA) substitution) at specific positions within the guide strand. Our studies were enabled by the synthesis of RNA containing a new, ribose-modified nucleoside analog (4'-C-methyladenosine). Importantly, the ADAR reaction is potently inhibited by LNA or 4'-C-methylation at different positions in the ADAR guide. While LNA at guide strand positions -1 and -2 block the ADAR reaction, 4'-C-methylation only inhibits at the -2 position. These effects are rationalized using high-resolution structures of ADAR-RNA complexes. This work sheds additional light on the mechanism of ADAR deamination and aids in the design of highly selective ADAR guide strands for therapeutic editing using chemically modified RNA.


Assuntos
Adenosina Desaminase , Edição de RNA , Ribose , Adenosina Desaminase/metabolismo , Adenosina Desaminase/genética , Adenosina Desaminase/química , Ribose/química , Ribose/metabolismo , Humanos , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/química , Metilação , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/química , Nucleosídeos/química , Nucleosídeos/metabolismo , RNA/metabolismo , RNA/química , Inosina/metabolismo , Inosina/química
19.
Mol Genet Metab ; 142(4): 108513, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38917675

RESUMO

INTRODUCTION: Congenital disorders of glycosylation (CDG) are a continuously expanding group of monogenic disorders that disrupt glycoprotein and glycolipid biosynthesis, leading to multi-systemic manifestations. These disorders are categorized into various groups depending on which part of the glycosylation process is impaired. The cardiac manifestations in CDG can significantly differ, not only across different types but also among individuals with the same genetic cause of CDG. Cardiomyopathy is an important phenotype in CDG. The clinical manifestations and progression of cardiomyopathy in CDG patients have not been well characterized. This study aims to delineate common patterns of cardiomyopathy across a range of genetic causes of CDG and to propose baseline screening and follow-up evaluation for this patient population. METHODS: Patients with molecular confirmation of CDG who were enrolled in the prospective or memorial arms of the Frontiers in Congenital Disorders of Glycosylation Consortium (FCDGC) natural history study were ascertained for the presence of cardiomyopathy based on a retrospective review of their medical records. All patients were evaluated by clinical geneticists who are members of FCDGC at their respective academic centers. Patients were screened for cardiomyopathy, and detailed data were retrospectively collected. We analyzed their clinical and molecular history, imaging characteristics of cardiac involvement, type of cardiomyopathy, age at initial presentation of cardiomyopathy, additional cardiac features, the treatments administered, and their clinical outcomes. RESULTS: Of the 305 patients with molecularly confirmed CDG participating in the FCDGC natural history study as of June 2023, 17 individuals, nine females and eight males, were identified with concurrent diagnoses of cardiomyopathy. Most of these patients were diagnosed with PMM2-CDG (n = 10). However, cardiomyopathy was also observed in other diagnoses, including PGM1-CDG (n = 3), ALG3-CDG (n = 1), DPM1-CDG (n = 1), DPAGT1-CDG (n = 1), and SSR4-CDG (n = 1). All PMM2-CDG patients were reported to have hypertrophic cardiomyopathy. Dilated cardiomyopathy was observed in three patients, two with PGM1-CDG and one with ALG3-CDG; left ventricular non-compaction cardiomyopathy was diagnosed in two patients, one with PGM1-CDG and one with DPAGT1-CDG; two patients, one with DPM1-CDG and one with SSR4-CDG, were diagnosed with non-ischemic cardiomyopathy. The estimated median age of diagnosis for cardiomyopathy was 5 months (range: prenatal-27 years). Cardiac improvement was observed in three patients with PMM2-CDG. Five patients showed a progressive course of cardiomyopathy, while the condition remained unchanged in eight individuals. Six patients demonstrated pericardial effusion, with three patients exhibiting cardiac tamponade. One patient with SSR4-CDG has been recently diagnosed with cardiomyopathy; thus, the progression of the disease is yet to be determined. One patient with PGM1-CDG underwent cardiac transplantation. Seven patients were deceased, including five with PMM2-CDG, one with DPAGT1-CDG, and one with ALG3-CDG. Two patients died of cardiac tamponade from pericardial effusion; for the remaining patients, cardiomyopathy was not necessarily the primary cause of death. CONCLUSIONS: In this retrospective study, cardiomyopathy was identified in ∼6% of patients with CDG. Notably, the majority, including all those with PMM2-CDG, exhibited hypertrophic cardiomyopathy. Some cases did not show progression, yet pericardial effusions were commonly observed, especially in PMM2-CDG patients, occasionally escalating to life-threatening cardiac tamponade. It is recommended that clinicians managing CDG patients, particularly those with PMM2-CDG and PGM1-CDG, be vigilant of the cardiomyopathy risk and risk for potentially life-threatening pericardial effusions. Cardiac surveillance, including an echocardiogram and EKG, should be conducted at the time of diagnosis, annually throughout the first 5 years, followed by check-ups every 2-3 years if no concerns arise until adulthood. Subsequently, routine cardiac examinations every five years are advisable. Additionally, patients with diagnosed cardiomyopathy should receive ongoing cardiac care to ensure the effective management and monitoring of their condition. A prospective study will be required to determine the true prevalence of cardiomyopathy in CDG.


Assuntos
Cardiomiopatias , Defeitos Congênitos da Glicosilação , Fenótipo , Humanos , Defeitos Congênitos da Glicosilação/genética , Defeitos Congênitos da Glicosilação/diagnóstico , Defeitos Congênitos da Glicosilação/patologia , Feminino , Masculino , Cardiomiopatias/genética , Cardiomiopatias/diagnóstico , Criança , Pré-Escolar , Adolescente , Lactente , Glicosilação , Seguimentos , Adulto , Estudos Retrospectivos , Adulto Jovem , Estudos Prospectivos , Recém-Nascido
20.
Sci Total Environ ; 945: 173706, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38866169

RESUMO

BACKGROUND: Air pollution is a modifiable risk factor for dementia. Yet, studies on specific sources of air pollution (i.e., toxic chemical emissions from industrial facilities) and dementia risk are scarce. We examined associations between toxicity-weighted concentrations of industrial pollution and dementia outcomes among a large, multi-site cohort of older adults. METHODS: Participants (n = 2770) were ≥ 65 years old (Mean = 75.3, SD = 5.1 years) from the Cardiovascular Health Cognition Study (1992-1999). Toxicity-weighted concentrations were estimated using the Risk Screening Environmental Indicator (RSEI) model which incorporates total reported chemical emissions with toxicity, fate, and transport models. Estimates were aggregated to participants' baseline census tract, averaged across 1988-1992, and log2-transformed. Dementia status was clinically adjudicated in 1998-1999 and categorized by subtype (Alzheimer's, vascular, mixed). We assessed whether RSEI-estimated toxicity-weighted concentrations were associated with 1) odds of prevalent dementia and 2) incident dementia risk by subtype. RESULTS: After adjusting for individual and census-tract level covariates, a doubling in toxicity-weighted concentrations was associated with 9 % higher odds of prevalent dementia (OR = 1.09, 95 % CI: 1.00, 1.19). In discrete-time survival models, each doubling in toxicity-weighted concentrations was associated with a 16 % greater hazard of vascular dementia (HR = 1.16, 95 % CI: 1.01, 1.34) but was not significantly associated with all-cause, Alzheimer's disease, or mixed dementia (p's > 0.05). DISCUSSION: Living in regions with higher toxicity-weighted concentrations was associated with higher odds of prevalent dementia and a higher risk of incident vascular dementia in this large, community-based cohort of older adults. These findings support the need for additional studies to examine whether toxic chemical emissions from industrial and federal facilities may be a modifiable target for dementia prevention.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Demência , Exposição Ambiental , Humanos , Demência/epidemiologia , Idoso , Masculino , Feminino , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Fatores de Risco , Idoso de 80 Anos ou mais
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