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1.
Genes (Basel) ; 15(4)2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38674386

ABSTRACT

Down syndrome (DS) is the most common form of inherited intellectual disability caused by trisomy of chromosome 21, presenting with intellectual impairment, craniofacial abnormalities, cardiac defects, and gastrointestinal disorders. The Ts65Dn mouse model replicates many abnormalities of DS. We hypothesized that investigation of the cerebral cortex of fluoxetine-treated trisomic mice may provide proteomic signatures that identify therapeutic targets for DS. Subcellular fractionation of synaptosomes from cerebral cortices of age- and brain-area-matched samples from fluoxetine-treated vs. water-treated trisomic and euploid male mice were subjected to HPLC-tandem mass spectrometry. Analysis of the data revealed enrichment of trisomic risk genes that participate in regulation of synaptic vesicular traffic, pre-synaptic and post-synaptic development, and mitochondrial energy pathways during early brain development. Proteomic analysis of trisomic synaptic fractions revealed significant downregulation of proteins involved in synaptic vesicular traffic, including vesicular endocytosis (CLTA, CLTB, CLTC), synaptic assembly and maturation (EXOC1, EXOC3, EXOC8), anterograde axonal transport (EXOC1), neurotransmitter transport to PSD (SACM1L), endosomal-lysosomal acidification (ROGDI, DMXL2), and synaptic signaling (NRXN1, HIP1, ITSN1, YWHAG). Additionally, trisomic proteomes revealed upregulation of several trafficking proteins, involved in vesicular exocytosis (Rab5B), synapse elimination (UBE3A), scission of endocytosis (DBN1), transport of ER in dendritic spines (MYO5A), presynaptic activity-dependent bulk endocytosis (FMR1), and NMDA receptor activity (GRIN2A). Chronic fluoxetine treatment of Ts65Dn mice rescued synaptic vesicular abnormalities and prevented abnormal proteomic changes in adult Ts65Dn mice, pointing to therapeutic targets for potential treatment of DS.


Subject(s)
Down Syndrome , Fluoxetine , Proteomics , Synaptic Vesicles , Animals , Fluoxetine/pharmacology , Mice , Down Syndrome/metabolism , Down Syndrome/drug therapy , Down Syndrome/genetics , Down Syndrome/pathology , Male , Proteomics/methods , Synaptic Vesicles/metabolism , Synaptic Vesicles/drug effects , Disease Models, Animal , Proteome/metabolism , Cerebral Cortex/metabolism , Cerebral Cortex/drug effects , Synaptosomes/metabolism , Synaptosomes/drug effects , Trisomy/genetics
2.
Microorganisms ; 12(4)2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38674741

ABSTRACT

Aging has been associated with a changed composition and function of the gut microbiota (GM). Here, we investigate the effects of the multi-strain probiotic HOWARU® Restore on GM composition and function in seniors. Ninety-eight healthy adult volunteers aged ≥75 years were enrolled in a randomised, double-blinded intervention (NCT02207140), where they received HOWARU Restore (1010 CFU) or the placebo daily for 24 weeks, with 45 volunteers from each group completing the intervention. Questionnaires monitoring the effects on gastro-intestinal discomfort and bowel movements were collected. Faecal samples for GM characterisation (qPCR, 16S rRNA gene amplicon sequencing) and metabolomics (GC-FID, 1H NMR) were collected at the baseline and after 24 weeks. In the probiotic group, self-reported gastro-intestinal discomfort in the form of flatulence was significantly decreased during the intervention. At the baseline, 151 'core species' (present in ≥95% of samples) were identified. Most core species belonged to the Lachnospiraceae and Ruminococcaceae families. Neither alpha diversity nor beta diversity or faecal metabolites was affected by probiotic intake. On the contrary, we observed high intra-individual GM stability, with 'individual' accounting for 72-75% of variation. In conclusion, 24 weeks of HOWARU Restore intake reduced gastro-intestinal discomfort in the form of flatulence in healthy seniors without significantly influencing GM composition or activity.

3.
Curr Microbiol ; 81(6): 143, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38627283

ABSTRACT

The cyanobacterium Synechococcus elongatus PCC 7942 holds significant potential as a biofactory for recombinant protein (RP) production due to its capacity to harness light energy and utilize CO2. This study aimed to enhance RP production by integration of native promoters and magnetic field application (MF) in S. elongatus PCC 7942. The psbA2 promoter, which responds to stress conditions, was chosen for the integration of the ZsGreen1 gene. Results indicated successful gene integration, affirming prior studies that showed no growth alterations in transgenic strains. Interestingly, exposure to 30 mT (MF30) demonstrated a increase in ZsGreen1 transcription under the psbA2 promoter, revealing the influence of MF on cyanobacterial photosynthetic machinery. This enhancement is likely attributed to stress-induced shifts in gene expression and enzyme activity. MF30 positively impacted photosystem II (PSII) without disrupting the electron transport chain, aligning with the "quantum-mechanical mechanism" theory. Notably, fluorescence levels and gene expression with application of 30 mT were significantly different from control conditions. This study showcases the efficacy of utilizing native promoters and MF for enhancing RP production in S. elongatus PCC 7942. Native promoters eliminate the need for costly exogenous inducers and potential cell stress. Moreover, the study expands the scope of optimizing RP production in photoautotrophic microorganisms, providing valuable insights for biotechnological applications.


Subject(s)
Synechococcus , Promoter Regions, Genetic , Synechococcus/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
4.
Chem Mater ; 36(6): 2810-2818, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38558918

ABSTRACT

Material design is increasingly used to realize desired functional properties, and the perovskite structure family is one of the richest and most diverse: perovskites are employed in many applications due to their structural flexibility and compositional diversity. Hexagonal, layered perovskite structures with chains of face-sharing transition metal oxide octahedra have attracted great interest as quantum materials due to their magnetic and electronic properties. Ba4MMn3O12, a member of the "12R" class of hexagonal, layered perovskites, contains trimers of face-sharing MnO6 octahedra that are linked by a corner-sharing, bridging MO6 octahedron. Here, we investigate cluster magnetism in the Mn3O12 trimers and the role of this bridging octahedron on the magnetic properties of two isostructural 12R materials by systematically changing the M4+ cation from nonmagnetic Ce4+ (f0) to magnetic Pr4+ (f1). We synthesized 12R-Ba4MMn3O12 (M= Ce, Pr) with high phase purity and characterized their low-temperature crystal structures and magnetic properties. Using substantially higher purity samples than previously reported, we confirm the frustrated antiferromagnetic ground state of 12R-Ba4PrMn3O12 below TN ≈ 7.75 K and explore the cluster magnetism of its Mn3O12 trimers. Despite being atomically isostructural with 12R-Ba4CeMn3O12, the f1 electron associated with Pr4+ causes much more complex magnetic properties in 12R-Ba4PrMn3O12. In 12R-Ba4PrMn3O12, we observe a sharp, likely antiferromagnetic transition at T2 ≈ 12.15 K and an additional transition at T1 ≈ 200 K, likely in canted antiferromagnetic order. These results suggest that careful variation of composition within the family of hexagonal, layered perovskites can be used to tune material properties using the complex role of the Pr4+ ion in magnetism.

5.
J Bone Miner Res ; 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38578978

ABSTRACT

Anabolic treatment is indicated for high and very-high risk patients with osteoporosis, but acceptance is limited because current anabolic medications require subcutaneous injections. The purpose of this study was to assess the effects of a novel orally administered parathyroid hormone (PTH) tablet on serum markers of bone formation [N-terminal propeptide of Type I procollagen (PINP) and osteocalcin (OC)] and bone resorption [crosslinked C-telopeptide (CTX)], bone mineral density (BMD) and safety in postmenopausal women with low BMD or osteoporosis. In this 6-month, double-blind, placebo-controlled study, 161 patients were randomized to oral PTH tablets containing 0.5, 1.0, 1.5, or 2.5 mg or placebo daily. Biochemical markers were assessed at 1, 2, 3 and 6 months and BMD of lumbar spine, total hip and femoral neck was measured at 6 months. Biochemical marker changes were dose dependent with minimal or no effect at the two lowest doses. At the highest dose (2.5 mg once daily), serum PINP and OC levels increased 30% within 1 month after oral PTH initiation (p < 0.0001), remained elevated through 3 months and were back to baseline at 6 months. In contrast, serum CTX levels declined 16% and 21% below baseline at 3 and 6 months respectively (both p ≤ 0.02). At 6 months, 2.5 mg tablets increased mean BMD vs placebo of the lumbar spine by 2.7%, total hip by 1.8%, and femoral neck by 2.8% (all p ≤ 0.01). There were no drug-related serious adverse events. The most common adverse events were headache, nausea, and dizziness. In contrast to subcutaneous PTH, the oral PTH tablet appears to increase BMD rapidly by the dual mechanism of stimulating formation and inhibiting bone resorption. This might be the first effective oral anabolic alternative to subcutaneous administration for the treatment of low BMD or osteoporosis.


Despite the superior benefits of bone building (anabolic) agents and guidelines supporting their use, these medications are used in a minority of patients for whom they are appropriate, in part because they require daily or monthly injections, which limit patient acceptance. An oral anabolic tablet has potential to address this substantial treatment gap. In this double-blind, placebo controlled, dose-finding randomized study, 161 postmenopausal women with low bone mineral density or osteoporosis were treated with varying doses of the active part of parathyroid hormone [PTH(1-34)] or placebo given in daily oral tablets for 6 months. The highest oral PTH tablet dose (2.5 mg), produced an increase in markers of bone formation while simultaneously decreasing the markers of bone breakdown. Significant gains in bone mineral density of the spine and hip were observed at the end of the 6-month study and there were no significant safety concerns. The 2.5 mg oral PTH tablet dose was well tolerated when patients were instructed to titrate up to the full dose. We conclude that this PTH tablet might be the first effective orally administered bone building medication and should be studied further in treatment of women with osteoporosis.

6.
IDCases ; 36: e01955, 2024.
Article in English | MEDLINE | ID: mdl-38646601

ABSTRACT

Flea-borne typhus (FBT), also known as murine typhus, is a zoonotic infection caused by R. typhi with world-wide distribution. In the United States, the infection is uncommon but remains endemic in some areas, including Los Angeles County. It typically manifests as a benign acute febrile illness but can be complicated in a minority of cases. Associated hemophagocytic lymphohistiocytosis (HLH) has been described in a limited number of cases. Here, we present a case of a patient with FBT complicated by HLH treated empirically with doxycycline with subsequent resolution of HLH. Also included is a review of the literature of other published cases.

7.
Brain Commun ; 6(2): fcae043, 2024.
Article in English | MEDLINE | ID: mdl-38482373

ABSTRACT

The progression of PET-based Braak stages correlates with cognitive deterioration in aging and Alzheimer's disease. Here, we investigate the association between PET-based Braak stages and functional impairment and assess whether PET-based Braak staging predicts a longitudinal decline in the performance of activities of daily living. In this cohort study, we evaluated cognitively unimpaired individuals and individuals with mild cognitive impairment or Alzheimer's disease dementia. Participants underwent [18F]MK6240 tau-PET, were assigned a PET-based Braak stage at baseline and were followed for a mean (SD) of 1.97 (0.66) years. Functional performance was evaluated with the Functional Activities Questionnaire, Everyday Cognition and functional Clinical Dementia Rating sum of boxes. Multiple linear regressions assessed the association of PET-based Braak stages with baseline functionality and with the longitudinal rate of change in functional scores, adjusting for age, sex and amyloid-ß load. We employed voxel-based regression models to investigate the association between functionality and tau-PET signal and assessed the voxel overlap with Braak regions of interest. We included 291 individuals (181 cognitively unimpaired, 56 amyloid-ß+ mild cognitive impairment and 54 amyloid-ß+ Alzheimer's disease) aged 70.60 (7.48) years. At baseline, PET-based Braak stages III-IV (ß = 0.43, P = 0.03) and V-VI (ß = 1.20, P < 0.0001) showed associations with poorer Functional Activities Questionnaire scores. Similarly, stages III-IV (ß = 0.43, P = 0.02) and V-VI (ß = 1.15, P < 0.0001) were associated with worse Everyday Cognition scores. Only stages V-VI were associated with higher functional Clinical Dementia Rating sum of boxes (ß = 1.17, P < 0.0001) scores. Increased tau-PET signals in all Braak regions of interest were linked to worse performance in all tools. The voxelwise analysis showed widespread cortical associations between functional impairment and tau-PET and high voxel overlap with Braak regions of interest. Baseline PET-based Braak stages V-VI predicted significant longitudinal functional decline as assessed by the Functional Activities Questionnaire (ß = 1.69, P < 0.0001), the Everyday Cognition (ß = 1.05, P = 0.001) and the functional Clinical Dementia Rating sum of boxes (ß = 1.29, P < 0.0001). Our results suggest that functional impairment increases with the severity of tau accumulation. These findings also indicate that PET-based Braak staging is a good predictor of functional impairment in the Alzheimer's disease continuum. Finally, our study provides evidence for the clinical significance of the PET-based Braak staging framework.

8.
NPJ Digit Med ; 7(1): 55, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38429464

ABSTRACT

Infertility affects 1-in-6 couples, with repeated intensive cycles of assisted reproductive technology (ART) required by many to achieve a desired live birth. In ART, typically, clinicians and laboratory staff consider patient characteristics, previous treatment responses, and ongoing monitoring to determine treatment decisions. However, the reproducibility, weighting, and interpretation of these characteristics are contentious, and highly operator-dependent, resulting in considerable reliance on clinical experience. Artificial intelligence (AI) is ideally suited to handle, process, and analyze large, dynamic, temporal datasets with multiple intermediary outcomes that are generated during an ART cycle. Here, we review how AI has demonstrated potential for optimization and personalization of key steps in a reproducible manner, including: drug selection and dosing, cycle monitoring, induction of oocyte maturation, and selection of the most competent gametes and embryos, to improve the overall efficacy and safety of ART.

9.
Occup Med (Lond) ; 74(3): 251-253, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38526854

ABSTRACT

This case report describes a 22-year-old female Ambulance Technician student who displayed human immunodeficiency virus (HIV) false positivity following a recent hepatitis B vaccination. Occupational health clinicians who work in a healthcare setting (with healthcare staff and/or students) should be aware of the possibility of false-positive HIV screening test results, and where a false positive is suspected, they should consider what the underlying cause could be and should consider whether further medical investigation is required.


Subject(s)
HIV Infections , Humans , Female , False Positive Reactions , HIV Infections/diagnosis , Young Adult , Hepatitis B/diagnosis , Mass Screening/methods , Hepatitis B Vaccines
10.
Gerodontology ; 2024 Jan 21.
Article in English | MEDLINE | ID: mdl-38247027

ABSTRACT

BACKGROUND: This systematic review investigated the prevalence of orofacial pain in patients with mild cognitive impairment (MCI) or dementia. MATERIALS AND METHODS: The search was conducted in five databases (Medline (Ovid), Embase (Ovid), CINAHL, Scopus and LILACS), in three grey literature sources and in included articles' reference lists. Three independent reviewers performed study selection, quality appraisal and data extraction. The risk of bias was assessed with the National Institutes of Health tool. Prevalence was calculated using the random-effects model. Subgroup analysis and meta-regression were used to explore the heterogeneity of results. RESULTS: The database and grey literature search led to 12 246 results, from which nine studies were included; a further four were selected through citation searching. The total sample comprised 6115 patients with dementia and 84 with MCI. All studies had high risk of bias. The overall estimated pooled prevalence of orofacial pain among dementia participants was 19.0% (95% CI, 11.0%-27.0%; I2 , 97.1%, P < .001). Only one study included MCI participants, among which the prevalence of orofacial pain was 20.5%. Subgroup analysis demonstrated that the different sources of diagnosis might explain the heterogeneity. A higher prevalence of orofacial pain was observed in dementia participants aged over 80 years or living in nursing homes. Meta-regression analysis showed a nonlinear relationship between age and the prevalence of orofacial pain. CONCLUSIONS: The pooled data from the primary studies revealed that 2 out of 10 patients with dementia have orofacial pain. Further research is needed to clarify the magnitude in individuals with MCI.

11.
Br J Radiol ; 97(1156): 794-802, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38268482

ABSTRACT

OBJECTIVES: The aim of this study was to generate an objective method to describe MRI data to assess response in the vertebrae of patients with metastatic hormone sensitive prostate cancer (mHSPC), treated with external beam radiation therapy and systemic therapy with Radium-223 and to correlate changes with clinical outcomes. METHODS: Three sets of whole-body MRI (WBMRI) images were utilized from 25 patients from the neo-adjuvant Androgen Deprivation Therapy pelvic Radiotherapy and RADium-223 (ADRRAD) clinical trial: MRI1 (up to 28 days before Radium-223), MRI2, and MRI3 (2 and 6 months post completion of Radium-223). Radiological response was assessed based on post baseline MRI images. Vertebrae were semi-automatically contoured in the sagittal T1-weighted (T1w) acquisitions, MRI intensity was measured, and spinal cord was used to normalize the measurements. The relationship between MRI intensity vs time to biochemical progression and radiology response was investigated. Survival curves were generated and splitting measures for survival and biochemical progression investigated. RESULTS: Using a splitting measure of 1.8, MRI1 was found to be a reliable quantitative indicator correlating with overall survival (P = 0.023) and biochemical progression (P = 0.014). MRI (3-1) and MRI (3-2) were found to be significant indicators for patients characterized by progressive/non-progressive disease (P = 0.021, P = 0.004) and biochemical progression within/after 12 months (P = 0.007, P = 0.001). CONCLUSIONS: We have identified a potentially useful objective measure of response on WBMRI of vertebrae containing bone metastases in mHSPC which correlates with survival/progression (prognostic) and radiology response (predictive). ADVANCES IN KNOWLEDGE: Measurements of T1w WBMRI normalized intensity may allow identifying potentially useful response biomarkers correlating with survival, radiological response and biochemical progression.


Subject(s)
Prostatic Neoplasms , Radium , Male , Humans , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/radiotherapy , Androgen Antagonists/therapeutic use , Androgens/therapeutic use , Prostate-Specific Antigen , Radium/therapeutic use
12.
Mol Neurodegener ; 19(1): 2, 2024 Jan 07.
Article in English | MEDLINE | ID: mdl-38185677

ABSTRACT

BACKGROUND: Antibody-based immunoassays have enabled quantification of very low concentrations of phosphorylated tau (p-tau) protein forms in cerebrospinal fluid (CSF), aiding in the diagnosis of AD. Mass spectrometry enables absolute quantification of multiple p-tau variants within a single run. The goal of this study was to compare the performance of mass spectrometry assessments of p-tau181, p-tau217 and p-tau231 with established immunoassay techniques. METHODS: We measured p-tau181, p-tau217 and p-tau231 concentrations in CSF from 173 participants from the TRIAD cohort and 394 participants from the BioFINDER-2 cohort using both mass spectrometry and immunoassay methods. All subjects were clinically evaluated by dementia specialists and had amyloid-PET and tau-PET assessments. Bland-Altman analyses evaluated the agreement between immunoassay and mass spectrometry p-tau181, p-tau217 and p-tau231. P-tau associations with amyloid-PET and tau-PET uptake were also compared. Receiver Operating Characteristic (ROC) analyses compared the performance of mass spectrometry and immunoassays p-tau concentrations to identify amyloid-PET positivity. RESULTS: Mass spectrometry and immunoassays of p-tau217 were highly comparable in terms of diagnostic performance, between-group effect sizes and associations with PET biomarkers. In contrast, p-tau181 and p-tau231 concentrations measured using antibody-free mass spectrometry had lower performance compared with immunoassays. CONCLUSIONS: Our results suggest that while similar overall, immunoassay-based p-tau biomarkers are slightly superior to antibody-free mass spectrometry-based p-tau biomarkers. Future work is needed to determine whether the potential to evaluate multiple biomarkers within a single run offsets the slightly lower performance of antibody-free mass spectrometry-based p-tau quantification.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/diagnosis , Amyloidogenic Proteins , Immunoassay , Mass Spectrometry , Biomarkers
13.
Angew Chem Int Ed Engl ; 63(6): e202317345, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38078805

ABSTRACT

Silver cluster-based solids have garnered considerable attention owing to their tunable luminescence behavior. While surface modification has enabled the construction of stable silver clusters, controlling interactions among clusters at the molecular level has been challenging due to their tendency to aggregate. Judicious choice of stabilizing ligands becomes pivotal in crafting a desired assembly. However, detailed photophysical behavior as a function of their cluster packing remained unexplored. Here, we modulate the packing pattern of Ag12 clusters by varying the nitrogen-based ligand. CAM-1 formed through coordination of the tritopic linker molecule and NC-1 with monodentate pyridine ligand; established via non-covalent interactions. Both the assemblies show ligand-to-metal-metal charge transfer (LMMCT) based cluster-centered emission band(s). Temperature-dependent photoluminescence spectra exhibit blue shifts at higher temperatures, which is attributed to the extent of the thermal reverse population of the S1 state from the closely spaced T1 state. The difference in the energy gap (ΔEST ) dictated by their assemblies played a pivotal role in the way that Ag12 cluster assembly in CAM-1 manifests a wider ΔEST and thus requires higher temperatures for reverse intersystem crossing (RISC) than assembly of NC-1. Such assembly-defined photoluminescence properties underscore the potential toolkit to design new cluster- assemblies with tailored optoelectronic properties.

14.
Conserv Biol ; 38(1): e14145, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37403804

ABSTRACT

Emerging technology has immense potential to increase the scale and efficiency of marine conservation. One such technology is large-area imaging (LAI), which relies on structure-from-motion photogrammetry to create composite products, including 3-dimensional (3-D) environmental models, that are larger in spatial extent than the individual images used to create them. Use of LAI has become widespread in certain fields of marine science, primarily to measure the 3D structure of benthic ecosystems and track change over time. However, the use of LAI in the field of marine conservation appears limited. We conducted a review of the coral reef literature on the use of LAI to identify research themes and regional trends in applications of this technology. We also surveyed 135 coral reef scientists and conservation practitioners to determine community familiarity with LAI, evaluate barriers practitioners face in using LAI, and identify applications of LAI believed to be most exciting or relevant to coral conservation. Adoption of LAI was limited primarily to researchers at institutions based in advanced economies and was applied infrequently to conservation, although conservation practitioners and survey respondents from emerging economies indicated they expect to use LAI in the future. Our results revealed disconnect between current LAI research topics and conservation priorities identified by practitioners, highlighting the need for more diverse, conservation-relevant research using LAI. We provide recommendations for how early adopters of LAI (typically Global North scientists from well-resourced institutions) can facilitate access to this conservation technology. These recommendations include developing training resources, creating partnerships for data storage and analysis, publishing standard operating procedures for LAI workflows, standardizing methods, developing tools for efficient data extraction from LAI products, and conducting conservation-relevant research using LAI.


Reducción de la brecha entre la investigación actual de imágenes de gran superficie y las necesidades de la conservación marina Resumen Las nuevas tecnologías tienen un enorme potencial para aumentar la escala y la eficiencia de la conservación marina. Una de ellas son las imágenes de gran superficie (IGS), que se basan en la fotogrametría de estructura a partir del movimiento para crear productos compuestos, incluidos modelos ambientales tridimensionales (3D), cuya extensión espacial es mayor que la de las imágenes individuales utilizadas para crearlos. El uso de las IGS se ha generalizado en determinados campos de las ciencias marinas, principalmente para medir la estructura tridimensional de los ecosistemas bentónicos y realizar un seguimiento de los cambios a lo largo del tiempo. Sin embargo, el uso de las IGS en el campo de la conservación marina parece limitado. Realizamos una revisión de la bibliografía sobre el uso de las IGS en los arrecifes de coral para identificar temas de investigación y tendencias regionales en las aplicaciones de esta tecnología. También encuestamos a 135 científicos de arrecifes de coral y profesionales de la conservación para determinar la familiaridad de la comunidad con las IGS, evaluar las barreras a las que se enfrentan los profesionales en el uso de las IGS e identificar sus aplicaciones consideradas como las más interesantes o relevantes para la conservación del coral. La adopción de las IGS se limitó principalmente a los investigadores de las instituciones con sede en las economías avanzadas y se aplicó con poca frecuencia a la conservación, aunque los profesionales de la conservación y los encuestados de las economías emergentes indicaron que esperan utilizar las IGS en el futuro. Nuestros resultados revelaron una desconexión entre los actuales temas de investigación de las IGS y las prioridades de conservación identificadas por los profesionales, lo que subraya la necesidad de una investigación más diversa y relevante para la conservación mediante el uso de las IGS.


Subject(s)
Anthozoa , Ecosystem , Animals , Conservation of Natural Resources/methods , Coral Reefs
15.
Int J Biometeorol ; 68(1): 57-67, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37880506

ABSTRACT

Crop irrigation requirements are usually estimated based on crop evapotranspiration (ETc) as determined by the reference evapotranspiration (ETo) and crop coefficient (Kc). There is a lack of knowledge on the irrigation requirements of tropical forage crops in Brazil, contrasting with the increasing use of irrigation in pastures. The effort of this study was to investigate what would be the water needs of tropical forages in Southern Brazil, based on a robust experimental database. The study was carried out in São Paulo State-Brazil using different forages species and their combinations [Guinea grass (GG); Guinea grass + black oat + ryegrass (GOR); Bermuda grass (BG), and Bermuda + black oat + ryegrass (BOR)]. The experimental fields were fully irrigated, and the Kc values were derived from ETc measurements on lysimeters; ETo was estimated using daily data from a nearby weather station and the standard FAO56 parameterization. Mean daily ETc values for GG, GOR, BG and BOR were 4.1, 2.9, 3.6, and 3.4 mm, respectively, and respective mean Kc values were 0.99, 0.90, 1.0, and 0.94. Average Kc values for all plots decreased as ETo increased, producing a negative Kc-ETo relationship, mainly when ETo reached values greater than 5 mm d-1. This was most likely due to internal plant stomatal resistance to vapor release from the leaves diffusing to the atmosphere at high ETo. So, the time-based Kc curves described by FAO 56 manual should be adjusted for the analyzed crops considering different ranges of ETo to improve the required irrigation depth.


Subject(s)
Agricultural Irrigation , Crops, Agricultural , Brazil , Weather , Water
16.
Alzheimers Dement ; 20(2): 1166-1174, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37920945

ABSTRACT

INTRODUCTION: We set out to identify tau PET-positive (A+T+) individuals among amyloid-beta (Aß) positive participants using plasma biomarkers. METHODS: In this cross-sectional study we assessed 234 participants across the AD continuum who were evaluated by amyloid PET with [18 F]AZD4694 and tau-PET with [18 F]MK6240 and measured plasma levels of total tau, pTau-181, pTau-217, pTau-231, and N-terminal tau (NTA-tau). We evaluated the performances of plasma biomarkers to predict tau positivity in Aß+ individuals. RESULTS: Highest associations with tau positivity in Aß+ individuals were found for plasma pTau-217 (AUC [CI95% ] = 0.89 [0.82, 0.96]) and NTA-tau (AUC [CI95% ] = 0.88 [0.91, 0.95]). Combining pTau-217 and NTA-tau resulted in the strongest agreement (Cohen's Kappa = 0.74, CI95%  = 0.57/0.90, sensitivity = 92%, specificity = 81%) with PET for classifying tau positivity. DISCUSSION: The potential for identifying tau accumulation in later Braak stages will be useful for patient stratification and prognostication in treatment trials and in clinical practice. HIGHLIGHTS: We found that in a cohort without pre-selection pTau-181, pTau-217, and NTA-tau showed the highest association with tau PET positivity. We found that in Aß+ individuals pTau-217 and NTA-tau showed the highest association with tau PET positivity. Combining pTau-217 and NTA-tau resulted in the strongest agreement with the tau PET-based classification.


Subject(s)
Alzheimer Disease , Humans , tau Proteins , Cross-Sectional Studies , Amyloid beta-Peptides , Biomarkers , Positron-Emission Tomography
17.
Nat Rev Endocrinol ; 20(3): 149-167, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38110672

ABSTRACT

Infertility affects one in six couples, with in vitro fertilization (IVF) offering many the chance of conception. Compared to the solitary oocyte produced during the natural menstrual cycle, the supraphysiological ovarian stimulation needed to produce multiple oocytes during IVF results in a dysfunctional luteal phase that can be insufficient to support implantation and maintain pregnancy. Consequently, hormonal supplementation with luteal phase support, principally exogenous progesterone, is used to optimize pregnancy rates; however, luteal phase support remains largely 'black-box' with insufficient clarity regarding the optimal timing, dosing, route and duration of treatment. Herein, we review the evidence on luteal phase support and highlight remaining uncertainties and future research directions. Specifically, we outline the physiological luteal phase, which is regulated by progesterone from the corpus luteum, and evaluate how it is altered by the supraphysiological ovarian stimulation used during IVF. Additionally, we describe the effects of the hormonal triggers used to mature oocytes on the degree of luteal phase support required. We explain the histological transformation of the endometrium during the luteal phase and evaluate markers of endometrial receptivity that attempt to identify the 'window of implantation'. We also cover progesterone receptor signalling, circulating progesterone levels associated with implantation, and the pharmacokinetics of available progesterone formulations to inform the design of luteal phase support regimens.


Subject(s)
Luteal Phase , Progesterone , Pregnancy , Female , Humans , Luteal Phase/physiology , Chorionic Gonadotropin , Reproductive Techniques, Assisted , Fertilization in Vitro/methods , Ovulation Induction/methods
18.
ACS Mater Au ; 3(6): 659-668, 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-38089657

ABSTRACT

Mesoporous silica particles (MSPs) have been studied for their potential therapeutic uses in controlling obesity and diabetes. Previous studies have shown that the level of digestion of starch by α-amylase is considerably reduced in the presence of MSPs, and it has been shown to be caused by the adsorption of α-amylase by MSPs. In this study, we tested a hypothesis of enzymatic deactivation and measured the activity of α-amylase together with MSPs (SBA-15) using comparably small CNP-G3 (2-chloro-4-nitrophenyl alpha-d-maltotrioside) as a substrate. We showed that pore-incorporated α-amylase was active and displayed higher activity and stability compared to amylase in solution (the control). We attribute this to physical effects: the coadsorption of CNP-G3 on the MSPs and the relatively snug fit of the amylase in the pores. Biosorption in this article refers to the process of removal or adsorption of α-amylase from its solution phase into the same solution dispersed in, or adsorbed on, the MSPs. Large quantities of α-amylase were biosorbed (about 21% w/w) on the MSPs, and high values of the maximum reaction rate (Vmax) and the Michaelis-Menten constant (KM) were observed for the enzyme kinetics. These findings show that the reduced enzymatic activity for α-amylase on MSP observed here and in earlier studies was related to the large probe (starch) being too large to adsorb in the pores, and potato starch has indeed a hydrodynamic diameter much larger than the pore sizes of MSPs. Further insights into the interactions and environments of the α-amylase inside the MSPs were provided by 1H fast magic-angle spinning (MAS) nuclear magnetic resonance (NMR) and 13C/15N dynamic nuclear polarization MAS NMR experiments. It could be concluded that the overall fold and solvation of the α-amylase inside the MSPs were nearly identical to those in solution.

19.
J Am Chem Soc ; 145(49): 26908-26914, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38041728

ABSTRACT

Ferromagnets constructed from nanometals of atomic precision are important for innovative advances in information storage, energy conversion, and spintronic microdevices. Considerable success has been achieved in designing molecular magnets, which, however, are challenging in preparation and may suffer from drawbacks on the incompatibility of high stability and strong ferromagnetism. Utilizing a state-of-the-art self-developed mass spectrometer and a homemade laser vaporization source, we have achieved a highly efficient preparation of pure iron clusters, and here, we report the finding of a strongly ferromagnetic metal-carbon cluster, Fe12C12-, simply by reacting the Fen- clusters with acetylene in proper conditions. The unique stability of this ferromagnetic Fe12C12- cluster is rooted in a plumb-bob structure pertaining to Jahn-Teller distortion. We classify Fe12C12- as a new member of metallo-carbohedrenes and elucidate its structural stability mechanism as well as its soft-landing deposition and magnetization measurements, providing promise for the exploration of potential applications.

20.
Vet Ophthalmol ; 2023 Nov 12.
Article in English | MEDLINE | ID: mdl-37952127

ABSTRACT

OBJECTIVES: To determine the prevalence of retinal lesions and describe the fundoscopic findings of retinopathy in Greyhound dogs in the Manawatu/Whanganui region of New Zealand. To examine possible associations between sex, age, and racing variables with retinopathy in the study population. To describe retinal histologic findings in seven Greyhounds with retinopathy in New Zealand. METHODS: Two hundred Greyhound dogs from the Manawatu/Whanganui region of New Zealand underwent fundoscopy and fundic photography to identify and score the degree of retinopathy. Associations between retinopathy and age, sex, as well as racing variables, were examined. Histologic examination of the retina was undertaken on the eyes of seven Greyhounds from the Manawatu and Canterbury regions previously diagnosed with retinopathy by fundoscopy. RESULTS: Fifty dogs (25.1%) were identified with retinopathy of varying degrees of severity. In at least one eye, 7.5% of dogs had mild retinopathy, 11.6% moderate retinopathy, and 6.0% severe retinopathy. Males were more likely to be affected in both eyes and with moderate or severe grades, than females. Increasing age was not associated with increased prevalence of retinopathy, nor increased grade of severity. Retinal histology identified multifocal retinal detachment in 5 of the 7 cases examined and other common lesions included choroidal necrosis and outer to full-thickness retinal atrophy in the absence of significant inflammation. CONCLUSIONS: Retinopathy is prevalent in Greyhounds in the Manawatu/Whanganui region of New Zealand, but more research is required to elucidate the etiopathogenesis. Consideration should be made to include mandatory eye health examination in racing Greyhound dogs.

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