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1.
Fertil Steril ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38729340

ABSTRACT

OBJECTIVE: We aimed to discover new variants associated with low ovarian reserve after gonadotoxic treatment among adult female childhood cancer survivors using a genome-wide association study approach. DESIGN: Genome-wide association study. SUBJECTS: A discovery cohort of adult female childhood cancer survivors, from the pan-European PanCareLIFE cohort (n=743; median age: 25.8 years), excluding those who received bilateral ovarian irradiation, bilateral oophorectomy, central nerve system or total body irradiation, or stem cell transplantation. Replication was attempted in the USA-based St. Jude Lifetime Cohort (n=391; median age: 31.3 years). EXPOSURE: Female childhood cancer survivors are at risk of therapy-related gonadal impairment. Alkylating agents are well-established risk factors, and the inter-individual variability in gonadotoxicity may be explained by genetic polymorphisms. Data were collected in real-life conditions and cyclophosphamide equivalent dose was used to quantify alkylation agent exposure. INTERVENTION: No intervention was performed. MAIN OUTCOME MEASURE: Anti-Müllerian hormone (AMH) levels served as a proxy for ovarian function and findings were combined in a meta-analysis. RESULTS: Three genome-wide significant (<5.0x10-8) and 16 genome-wide suggestive (<5.0x10-6) loci were associated with log-transformed AMH levels, adjusted for cyclophosphamide equivalent dose of alkylating agents, age at diagnosis, and age at study in the PanCareLIFE cohort. Based on effect allele frequency (EAF) (>0.01 if not genome-wide significant), p-value (<5.0×10-6), and biological relevance, 15 SNPs were selected for replication. None of the SNPs were statistically significantly associated with AMH levels. A meta-analysis indicated that rs78861946 was associated at borderline genome-wide statistical significance (Reference/effect allele: C/T; EAF: 0.04, Beta (SE): -0.484 (0.091), p-value= 9.39×10-8). CONCLUSION: This study found no genetic variants associated with a lower ovarian reserve after gonadotoxic treatment, as the findings of this GWAS were not statistically significant replicated in the replication cohort. Suggestive evidence for potential importance of one variant is briefly discussed, but the lack of statistical significance calls for larger cohort sizes. As the population of childhood cancer survivors is increasing, large-scale and systematic research is needed to identify genetic variants that could aid predictive risk models of gonadotoxicity and as well as fertility preservation options for childhood cancer survivors.

2.
Can J Public Health ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38713364

ABSTRACT

OBJECTIVE: South Asians represent the largest non-white ethnic group in Canada and were disproportionately impacted by the COVID-19 pandemic. We sought to determine the factors associated with vaccine hesitancy in South Asian Canadians. METHODS: We conducted a cross-sectional analysis of vaccine hesitancy using data collected at the baseline assessment of a prospective cohort study, COVID CommUNITY South Asian. Participants (18 + years) were recruited from the Greater Toronto and Hamilton Area in Ontario (ON) and the Greater Vancouver Area in British Columbia (BC) between April and November 2021. Demographic characteristics and vaccine attitudes measured by the Vaccine Attitudes Examination (VAX) scale were collected. Each item is scored on a 6-point Likert scale, and higher scores reflect greater hesitancy. A multivariable linear mixed effects model was used to identify sociodemographic factors associated with vaccine hesitancy, adjusting for multiple covariates. RESULTS: A total of 1496 self-identified South Asians (52% female) were analyzed (mean age = 38.5 years; standard deviation (SD): 15.3). The mean VAX score was 3.2, SD: 0.8 [range: 1.0‒6.0]. Factors associated with vaccine hesitancy included: time since immigration (p = 0.04), previous COVID-19 infection (p < 0.001), marital status (p < 0.001), living in a multigenerational household (p = 0.03), age (p = 0.02), education (p < 0.001), and employment status (p = 0.001). CONCLUSION: Among South Asians living in ON and BC, time since immigration, prior COVID-19 infection, marital status, living in a multigenerational household, age, education, and employment status were associated with vaccine hesitancy. This information can be used to address vaccine hesitancy in the South Asian population in future COVID-19 waves or pandemics.


RéSUMé: OBJECTIF: Les Asiatiques du Sud, qui représentent le plus grand groupe ethnique non-blanc au Canada, ont été démesurément touchés par la pandémie de COVID-19. Nous avons cherché à déterminer les facteurs associés à l'hésitation vaccinale chez les Canadiennes et les Canadiens asiatiques du Sud. MéTHODE: Nous avons mené une analyse transversale de l'hésitation vaccinale à l'aide des données collectées durant l'évaluation préliminaire d'une étude de cohorte prospective du nom de COVID CommUNITY South Asian. Les personnes participantes (18 ans et plus) ont été recrutées dans la région du grand Toronto et de Hamilton, en Ontario, et dans la région du Grand Vancouver, en Colombie-Britannique, entre avril et novembre 2021. Le profil démographique et les attitudes face aux vaccins, mesurées selon l'échelle Vaccine Attitudes Examination (VAX), ont été obtenus. Chaque élément a été noté selon une échelle de Likert en 6 points (plus la note est élevée, plus l'hésitation vaccinale est importante). Un modèle linéaire multivarié à effets mixtes a servi à identifier les facteurs sociodémographiques associés à l'hésitation vaccinale, en rajustant les données pour tenir compte de plusieurs covariables. RéSULTATS: En tout, 1 496 personnes s'identifiant comme étant Asiatiques du Sud (dont 52 % de femmes) ont été analysées (âge moyen = 38,5 ans; écart-type [S] : 15,3). La note VAX moyenne était de 3,2, S : 0,8 [intervalle : 1,0‒6,0]. Les facteurs associés à l'hésitation vaccinale étaient : le temps écoulé depuis l'immigration (p = 0,04), une infection antérieure par la COVID-19 (p < 0,001), l'état matrimonial (p < 0,001), le fait de vivre dans un ménage multigénérationnel (p = 0,03), l'âge (p = 0,02), l'instruction (p < 0,001) et la situation d'emploi (p = 0,001). CONCLUSION: Chez les Asiatiques du Sud vivant en Ontario et en Colombie-Britannique, le temps écoulé depuis l'immigration, une infection antérieure par la COVID-19, l'état matrimonial, le fait de vivre dans un ménage multigénérationnel, l'âge, l'instruction et la situation d'emploi étaient associés à l'hésitation vaccinale. Ces informations peuvent être utilisées pour aborder l'hésitation vaccinale dans la population asiatique du Sud lors de vagues de COVID-19 ou de pandémies futures.

3.
Sleep Breath ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38717716

ABSTRACT

PURPOSE: It is well established that, together with a multitude of other adverse effects on health, severe obstructive sleep apnoea causes reduced cerebral perfusion and, in turn, reduced cerebral function. Less clear is the impact of moderate obstructive sleep apnoea (OSA). Our aim was to determine if cerebral blood flow is impaired in people diagnosed with moderate OSA. METHODS: Twenty-four patients diagnosed with moderate OSA (15 ≤ apnoea-hypopnea index (AHI) < 30) were recruited (aged 32-72, median 59 years, 10 female). Seven controls (aged 42-73 years, median 62 years, 4 female) with an AHI < 5 were also recruited. The OSA status of all participants was confirmed at baseline by unattended polysomnography and they had an MRI arterial-spin-labelling scan of cerebral perfusion. RESULTS: Neither global perfusion nor voxel-wise perfusion differed significantly between the moderate-OSA and control groups. We also compared the average perfusion across three regional clusters, which had been found in a previous study to have significant perfusion differences with moderate-severe OSA versus control, and found no significant difference in perfusion between the two groups. The perfusions were also very close, with means of 50.2 and 51.8 mL/100 g/min for the moderate-OSAs and controls, respectively, with a negligible effect size (Cohen's d = 0.10). CONCLUSION: We conclude that cerebral perfusion is not impaired in people with moderate OSA and that cerebral flow regulatory mechanisms can cope with the adverse effects which occur in moderate OSA. This is an important factor in clinical decisions for prescription of continuous positive airway pressure therapy (CPAP).

4.
Article in English | MEDLINE | ID: mdl-38698952

ABSTRACT

Objective: To compare outcomes between patients discharged on intravenous (IV) versus oral (PO) antibiotics for the treatment of orthopedic infections, after creation of an IV-to-PO guideline, at a single academic medical center in the United States. Methods: This was a retrospective, propensity score matched, cohort study of adult patients hospitalized for orthopedic infections from September 30, 2020, to April 30, 2022. Patients discharged on PO antibiotics were matched to patients discharged on IV antibiotics. The primary outcome was one-year treatment failure following discharge. Secondary outcomes were incidence of 60-day treatment failure, adverse drug events (ADE), readmissions, infectious disease clinic "no-show" rates, and emergency department (ED) encounters. Results: Ninety PO-treated patients were matched to 90 IV-treated patients. Baseline characteristics were similar in the two groups after matching. There was no significant difference in the proportions of patients on PO versus IV antibiotics experiencing treatment failure at one year (26% vs 31%, P = .47). There were no significant differences for any secondary outcomes: treatment failure within 60 days (13% vs 14%, P = 1.00), ADE (13% vs 11%, P = .82), unplanned readmission (17% vs 21%, P = .57), or ED encounters (9% vs 18%, P = .54). Survival analyses identified no significant differences in time-to-event between PO and IV treatment for any of the outcomes assessed. Conclusions: There were no appreciable differences in outcomes between patients discharged on PO compared to IV regimens. Antimicrobial stewardship interventions to increase prescribing of PO antibiotics for the treatment of orthopedic infections should be encouraged.

6.
Nat Commun ; 15(1): 3998, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38734704

ABSTRACT

Symmetry-protected band degeneracy, coupled with a magnetic order, is the key to realizing novel magnetoelectric phenomena in topological magnets. While the spin-polarized nodal states have been identified to introduce extremely-sensitive electronic responses to the magnetic states, their possible role in determining magnetic ground states has remained elusive. Here, taking external pressure as a control knob, we show that a metal-insulator transition, a spin-reorientation transition, and a structural modification occur concomitantly when the nodal-line state crosses the Fermi level in a ferrimagnetic semiconductor Mn3Si2Te6. These unique pressure-driven magnetic and electronic transitions, associated with the dome-shaped Tc variation up to nearly room temperature, originate from the interplay between the spin-orbit coupling of the nodal-line state and magnetic frustration of localized spins. Our findings highlight that the nodal-line states, isolated from other trivial states, can facilitate strongly tunable magnetic properties in topological magnets.

7.
Lancet Planet Health ; 8(5): e327-e333, 2024 May.
Article in English | MEDLINE | ID: mdl-38729672

ABSTRACT

Health care contributes 4·4% of global net carbon emissions. Hospitals are resource-intensive settings, using a large amount of supplies in patient care and have high energy, ventilation, and heating needs. This Viewpoint investigates emissions related to health care in a patient's last year of life. End of life (EOL) is a period when health-care use and associated emissions production increases exponentially due primarily to hospital admissions, which are often at odds with patients' values and preferences. Potential solutions detailed within this Viewpoint are facilitating advanced care plans with patients to ensure their EOL wishes are clear, beginning palliative care interventions earlier when treating a life-limiting illness, deprescribing unnecessary medications because medications and their supply chains make up a significant portion of health-care emissions, and, enhancing access to low-intensity community care settings (eg, hospices) within the last year of life if home care is not available. Our analysis was done using Canadian data, but the findings can be applied to other high-income countries.


Subject(s)
Greenhouse Gases , Terminal Care , Humans , Canada , Greenhouse Gases/analysis
8.
Int J Neonatal Screen ; 10(2)2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38651399

ABSTRACT

In the United States and around the world, newborns are screened on a population basis for conditions benefiting from pre-symptomatic diagnosis and treatment. The number of screened conditions continues to expand as novel technologies for screening, diagnosing, treating, and managing disease are discovered. While screening all newborns facilitates early diagnosis and treatment, most screened conditions are treatable but not curable. Patients identified by newborn screening often require lifelong medical management and community support to achieve the best possible outcome. To advance the long-term follow-up of infants identified through newborn screening (NBS), the Long-Term Follow-up Cares and Check Initiative (LTFU-Cares and Check) designed, implemented, and evaluated a system of longitudinal data collection and annual reporting engaging parents, clinical providers, and state NBS programs. The LTFU-Cares and Check focused on newborns identified with spinal muscular atrophy (SMA) through NBS and the longitudinal health information prioritized by parents and families. Pediatric neurologists who care for newborns with SMA entered annual data, and data tracking and visualization tools were delivered to state NBS programs with a participating clinical center. In this publication, we report on the development, use of, and preliminary results from the LTFU-Cares and Check Initiative, which was designed as a comprehensive model of LTFU. We also propose next steps for achieving the goal of a national system of LTFU for individuals with identified conditions by meaningfully engaging public health agencies, clinicians, parents, families, and communities.

9.
medRxiv ; 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38585825

ABSTRACT

Collagen VI-related dystrophies (COL6-RDs) manifest with a spectrum of clinical phenotypes, ranging from Ullrich congenital muscular dystrophy (UCMD), presenting with prominent congenital symptoms and characterised by progressive muscle weakness, joint contractures and respiratory insufficiency, to Bethlem muscular dystrophy, with milder symptoms typically recognised later and at times resembling a limb girdle muscular dystrophy, and intermediate phenotypes falling between UCMD and Bethlem muscular dystrophy. Despite clinical and immunohistochemical features highly suggestive of COL6-RD, some patients had remained without an identified causative variant in COL6A1, COL6A2 or COL6A3. With combined muscle RNA-sequencing and whole-genome sequencing we uncovered a recurrent, de novo deep intronic variant in intron 11 of COL6A1 (c.930+189C>T) that leads to a dominantly acting in-frame pseudoexon insertion. We subsequently identified and have characterised an international cohort of forty-four patients with this COL6A1 intron 11 causative variant, one of the most common recurrent causative variants in the collagen VI genes. Patients manifest a consistently severe phenotype characterised by a paucity of early symptoms followed by an accelerated progression to a severe form of UCMD, except for one patient with somatic mosaicism for this COL6A1 intron 11 variant who manifests a milder phenotype consistent with Bethlem muscular dystrophy. Characterisation of this individual provides a robust validation for the development of our pseudoexon skipping therapy. We have previously shown that splice-modulating antisense oligomers applied in vitro effectively decreased the abundance of the mutant pseudoexon-containing COL6A1 transcripts to levels comparable to the in vivo scenario of the somatic mosaicism shown here, indicating that this therapeutic approach carries significant translational promise for ameliorating the severe form of UCMD caused by this common recurrent COL6A1 causative variant to a Bethlem muscular dystrophy phenotype.

10.
J Neuromuscul Dis ; 11(3): 687-699, 2024.
Article in English | MEDLINE | ID: mdl-38607761

ABSTRACT

BACKGROUND: Duchenne muscular dystrophy (DMD) is a rare, degenerative, recessive X-linked neuromuscular disease. Mutations in the gene encoding dystrophin lead to the absence of functional dystrophin protein. Individuals living with DMD exhibit progressive muscle weakness resulting in loss of ambulation and limb function, respiratory insufficiency, and cardiomyopathy, with multiorgan involvement. Adeno-associated virus vector-mediated gene therapy designed to enable production of functional dystrophin protein is a new therapeutic strategy. Delandistrogene moxeparvovec (Sarepta Therapeutics, Cambridge, MA) is indicated for treatment of ambulatory pediatric patients aged 4 through 5 years with DMD who have an indicated mutation in the DMD gene. OBJECTIVE: Evidence-based considerations for management of potential adverse events following gene therapy treatment for DMD are lacking in clinical literature. Our goal was to provide interdisciplinary consensus considerations for selected treatment-related adverse events (TRAEs) (vomiting, acute liver injury, myocarditis, and immune-mediated myositis) that may arise following gene therapy dosing with delandistrogene moxeparvovec. METHODS: An interdisciplinary panel of 12 specialists utilized a modified Delphi process to develop consensus considerations for the evaluation and management of TRAEs reported in delandistrogene moxeparvovec clinical studies. Panelists completed 2 Questionnaires prior to gathering for an in-person discussion. Consensus was defined as a majority (≥58% ; 7/12) of panelists either agreeing or disagreeing. RESULTS: Panelists agreed that the choice of baseline assessments should be informed by individual clinical indications, the treating provider's judgment, and prescribing information. Corticosteroid dosing for treatment of TRAEs should be optimized by considering individual risk versus benefit for each indication. In all cases involving patients with a confirmed TRAE, consultations with appropriate specialists were suggested. CONCLUSIONS: The Delphi Panel established consensus considerations for the evaluation and management of potential TRAEs for patients receiving delandistrogene moxeparvovec, including vomiting, acute liver injury, myocarditis, and immune-mediated myositis.


Subject(s)
Biological Products , Genetic Therapy , Muscular Dystrophy, Duchenne , Recombinant Fusion Proteins , Humans , Muscular Dystrophy, Duchenne/therapy , Muscular Dystrophy, Duchenne/genetics , Genetic Therapy/methods , Delphi Technique , Myocarditis/therapy , Child, Preschool
11.
Neurohospitalist ; 14(2): 182-185, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38666277

ABSTRACT

A single center had a collaborative, multidisciplinary review to determine how to best implement new acute ischemic stroke trials involving large vessel occlusions. A flow diagram process map was created for clinical decision support. Patients were divided into four groups based upon size of infarct and timing of presentation. The process map, available in the electronic health record (EHR) for clinicians to reference, guides the selection of patients for endovascular therapy with neuroimaging. In addition, the process map offers guidance for discussions with families and patients experiencing large vessel occlusions with both small and large core infarcts. This manuscript describes the process of creating the process map through a multidisciplinary review and discussion, with points of controversy and how these were addressed.

13.
Article in English | MEDLINE | ID: mdl-38682316

ABSTRACT

California halibut (Paralichthys californicus) is a candidate species for aquaculture and stock enhancement. These applications rely on sex control, either to maximize the production of faster growing females or to match sex ratios in the wild. Other paralichthids exhibit temperature-dependent sex determination (TSD), but the presence and pattern of TSD is not well defined in California halibut. Juvenile California halibut were cultured at three distinct temperatures (15°C, 19°C, and 23°C) through the developmental period presumed to be thermosensitive based on findings from congeners. Sex ratios were quantified in each treatment using phenotypic sex identification techniques applied early (molecular biomarkers; 51-100 mm total length [TL]) and late (visual examination of the gonads; ≥100 mm TL) in the juvenile phase. Both techniques indicated similar sex determination trends at each temperature, with overall sex ratios assessed as 49.9% male at 15°C, 74.5% male at 19°C, and 98.2% male at 23°C. Growth rates were highest at 23°C and lowest at 15°C, with intrinsically fast- and slow-growing individuals at all temperatures. At 15°C and 19°C, females comprised a higher proportion among the fast growers than they did among the slow growers. These data show that California halibut exhibit TSD, with temperatures of 19°C and 23°C masculinizing fish while 15°C appears to produce a 1:1 sex ratio. This study will help optimize sex ratios and growth in hatcheries through thermal manipulation. Furthermore, the developed biomolecular tools and identified temperature thresholds will be important in future work to understand the influence of global warming on wild population demographics.

14.
Pediatrics ; 153(5)2024 May 01.
Article in English | MEDLINE | ID: mdl-38682258

ABSTRACT

BACKGROUND: Nearly 25% of antibiotics prescribed to children are inappropriate or unnecessary, subjecting patients to avoidable adverse medication effects and cost. METHODS: We conducted a quality improvement initiative across 118 hospitals participating in the American Academy of Pediatrics Value in Inpatient Pediatrics Network 2020 to 2022. We aimed to increase the proportion of children receiving appropriate: (1) empirical, (2) definitive, and (3) duration of antibiotic therapy for community-acquired pneumonia, skin and soft tissue infections, and urinary tract infections to ≥85% by Jan 1, 2022. Sites reviewed encounters of children >60 days old evaluated in the emergency department or hospital. Interventions included monthly audit with feedback, educational webinars, peer coaching, order sets, and a mobile app containing site-specific, antibiogram-based treatment recommendations. Sites submitted 18 months of baseline, 2-months washout, and 10 months intervention data. We performed interrupted time series (analyses for each measure. RESULTS: Sites reviewed 43 916 encounters (30 799 preintervention, 13 117 post). Overall median [interquartile range] adherence to empirical, definitive, and duration of antibiotic therapy was 67% [65% to 70%]; 74% [72% to 75%] and 61% [58% to 65%], respectively at baseline and was 72% [71% to 72%]; 79% [79% to 80%] and 71% [69% to 73%], respectively, during the intervention period. Interrupted time series revealed a 13% (95% confidence interval: 1% to 26%) intercept change at intervention for empirical therapy and a 1.1% (95% confidence interval: 0.4% to 1.9%) monthly increase in adherence per month for antibiotic duration above baseline rates. Balancing measures of care escalation and revisit or readmission did not increase. CONCLUSIONS: This multisite collaborative increased appropriate antibiotic use for community-acquired pneumonia, skin and soft tissue infections, and urinary tract infection among diverse hospitals.


Subject(s)
Anti-Bacterial Agents , Quality Improvement , Urinary Tract Infections , Humans , Anti-Bacterial Agents/therapeutic use , Urinary Tract Infections/drug therapy , Child , United States , Community-Acquired Infections/drug therapy , Child, Preschool , Infant , Antimicrobial Stewardship , Soft Tissue Infections/drug therapy , Pneumonia/drug therapy , Female , Guideline Adherence , Practice Patterns, Physicians' , Inappropriate Prescribing/prevention & control , Male
15.
Brain Res ; 1837: 148958, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38685371

ABSTRACT

Vocal and swallowing deficits are common in Parkinson disease (PD). Because these impairments are resistant to dopamine replacement therapies, vocal and lingual exercise are the primary treatment, but not all individuals respond to exercise and neural mechanisms of treatment response are unclear. To explore putative mechanisms, we used the progressive Pink1-/- rat model of early to mid-stage PD and employed vocal and lingual exercises at 6- and 10-months of age in male Pink1-/- and wild type (WT) rats. We hypothesized that vocal and lingual exercise would improve vocal and tongue use dynamics and increase serotonin (5HT) immunoreactivity in related brainstem nuclei. Rats were tested at baseline and after 8 weeks of exercise or sham exercise. At early-stage PD (6 months), vocal exercise resulted in increased call complexity, but did not change intensity, while at mid-stage (10 months), vocal exercise no longer influenced vocalization complexity. Lingual exercise increased tongue force generation and reduced relative optical density of 5HT in the hypoglossal nucleus at both time points. The effects of vocal and lingual exercise at these time points are less robust than in prodromal stages observed in previous work, suggesting that early exercise interventions may yield greater benefit. Future work targeting optimization of exercise at later time points may facilitate clinical translation.

16.
Mol Biol Cell ; 35(6): mr3, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38630519

ABSTRACT

Dendritic spines, the mushroom-shaped extensions along dendritic shafts of excitatory neurons, are critical for synaptic function and are one of the first neuronal structures disrupted in neurodevelopmental and neurodegenerative diseases. Microtubule (MT) polymerization into dendritic spines is an activity-dependent process capable of affecting spine shape and function. Studies have shown that MT polymerization into spines occurs specifically in spines undergoing plastic changes. However, discerning the function of MT invasion of dendritic spines requires the specific inhibition of MT polymerization into spines, while leaving MT dynamics in the dendritic shaft, synaptically connected axons and associated glial cells intact. This is not possible with the unrestricted, bath application of pharmacological compounds. To specifically disrupt MT entry into spines we coupled a MT elimination domain (MTED) from the Efa6 protein to the actin filament-binding peptide LifeAct. LifeAct was chosen because actin filaments are highly concentrated in spines and are necessary for MT invasions. Temporally controlled expression of this LifeAct-MTED construct inhibits MT entry into dendritic spines, while preserving typical MT dynamics in the dendrite shaft. Expression of this construct will allow for the determination of the function of MT invasion of spines and more broadly, to discern how MT-actin interactions affect cellular processes.


Subject(s)
Dendritic Spines , Microtubules , Polymerization , Microtubules/metabolism , Dendritic Spines/metabolism , Animals , Actins/metabolism , Actin Cytoskeleton/metabolism , Neurons/metabolism , Rats , Microfilament Proteins/metabolism
17.
bioRxiv ; 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38496454

ABSTRACT

Dendritic spines, the mushroom-shaped extensions along dendritic shafts of excitatory neurons, are critical for synaptic function and are one of the first neuronal structures disrupted in neurodevelopmental and neurodegenerative diseases. Microtubule (MT) polymerization into dendritic spines is an activity-dependent process capable of affecting spine shape and function. Studies have shown that MT polymerization into spines occurs specifically in spines undergoing plastic changes. However, discerning the function of MT invasion of dendritic spines requires the specific inhibition of MT polymerization into spines, while leaving MT dynamics in the dendritic shaft, synaptically connected axons and associated glial cells intact. This is not possible with the unrestricted, bath application of pharmacological compounds. To specifically disrupt MT entry into spines we coupled a MT elimination domain (MTED) from the Efa6 protein to the actin filament-binding peptide LifeAct. LifeAct was chosen because actin filaments are highly concentrated in spines and are necessary for MT invasions. Temporally controlled expression of this LifeAct-MTED construct inhibits MT entry into dendritic spines, while preserving typical MT dynamics in the dendrite shaft. Expression of this construct will allow for the determination of the function of MT invasion of spines and more broadly, to discern how MT-actin interactions affect cellular processes.

18.
J Diet Suppl ; : 1-9, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38528721

ABSTRACT

INTRODUCTION: Clinicians have limited options outside controlled substances to address sleep disturbance, which left untreated can negatively affect patient outcomes in cardiovascular health, mental health, immunologic function, and more. For some, genetic factors may influence sleep disturbances. L-methylfolate, the active form of folate, plays a critical role in regulation of monoamine neurotransmitters known to have significant impact on sleep regulation: dopamine, serotonin, norepinephrine. Single nucleotide polymorphisms of the enzyme methylene-tetrahydrofolate-reductase are common and can impact monoamine production. The goal of this study was to evaluate effects of L-methylfolate supplementation on sleep in a cohort with reduced methylene tetrahydrofolate reductase (MTHFR) activity. METHODS: A retrospective cohort of patients being treated with L-methylfolate in a concierge medical clinic setting was studied. Patients presenting with sleep complaints were evaluated using the Patient-Reported Outcomes Measurement Information System at baseline. Patients with known MTHFR polymorphisms at either C667T and/or A1298C were recommended 5 mg of L-methylfolate daily and were reevaluated at 2 wks, at 4 wks, and at 8 wks of supplementation. Statistical comparisons were made utilizing ANOVA and T-test comparisons. RESULTS: Ten were included in the final cohort: six male and four female, average age 43 ± 16 years. Beginning at wk 2, average sleep disturbance improved significantly by -6.94 points (p = 0.005) and by 8 wks, all patients had improvement with a -14.34 change in disturbance from baseline (p = 0.001). CONCLUSION: Improvement in sleep disturbance was seen in both low and intermediate function phenotypes. L-methylfolate may be useful for improving sleep in patients with MTHFR polymorphism.

19.
Diabetes Care ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38530948

ABSTRACT

OBJECTIVE: This post hoc analysis assessed change from baseline to week 52 in glycemic parameters for tirzepatide (5, 10, 15 mg) versus insulin degludec (SURPASS-3 trial) and glargine (SURPASS-4 trial) in people with type 2 diabetes and different baseline glycemic patterns, based on fasting serum glucose (FSG) and postprandial glucose (PPG) values. RESEARCH DESIGN AND METHODS: Participant subgroups with low FSG/low PPG, low FSG/high PPG, high FSG/low PPG, and high FSG/high PPG were defined according to the median values of these measures. RESULTS: All tirzepatide doses and basal insulins were associated with decreased HbA1c, FSG, and PPG values from baseline to week 52 in all subgroups (P < 0.05). Within each subgroup, HbA1c and PPG decreases were greater with tirzepatide than insulin (P < 0.05). FSG decreases were generally similar. There were no differential treatment effects by FSG/PPG subgroup. CONCLUSIONS: In this post hoc analysis, tirzepatide was associated with superior glycemic control compared with insulin, irrespective of baseline glycemic pattern.

20.
RSC Adv ; 14(13): 8963-8970, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38495992

ABSTRACT

The programming of widely distributed iterative fungal hr-PKS is mysterious, yet it is central for generating polyketide natural product diversity by controlling the chain length, ß-processing level and methylation patterns of fungal polyketides. For the iterative hr-PKS TENS, responsible for producing the pentaketide-tyrosine hybrid pretenellin A 1, the chain length programming is known to be determined by the KR domain. Structure prediction of the KR domain enabled the identification of a relevant substrate binding helix, which was the focus of swap experiments with corresponding sequences from the related hr-PKS DMBS and MILS that produce similar hexa- and heptaketides (2, 3). The investigations of chimeric TENS variants expressed in vivo in the host Aspergillus oryzae NSAR1 revealed the substrate binding helix as a promising target for further investigations, evidenced by observed increase of the chain length during swap experiments. Building on these findings, rational engineering of TENS was applied based on structural analysis and sequence alignment. A minimal set of four simultaneous amino acid mutations achieved the re-programming of TENS by producing hexaketides in minor amounts. To refine our understanding and minimize the number of mutations impacting polyketide chain length, we conducted an alanine scan, pinpointing crucial amino acid positions. Our findings give indications on the intrinsic programming of hr-PKS domains by minimal changes in the amino acid sequence as one influence factor for programming.

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