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1.
Pediatr Neurosurg ; 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38684141

ABSTRACT

INTRODUCTION: At our institution, revascularization after indirect moyamoya surgery is routinely evaluated using magnetic resonance angiography (MRA) rather than catheter angiography. This study reviews how revascularization can be visualized on axial MRA versus catheter angiography and compares clinical outcomes of surgeries evaluated by routine postoperative MRA versus routine catheter angiography. METHODS: We reviewed the records of all patients treated at our institution who underwent unilateral encephaloduroarteriosynangiosis (EDAS)/pial synangiosis 2004-2021 at 1-21 years of age. Inclusion criteria included undergoing preoperative MRA within 18 months of surgery and postoperative MRA 3 to 30 months after surgery. Clinical outcome measures included postoperative stroke and transient ischemic attacks (TIAs), changes in symptoms (improved, unchanged, worsened), and new postoperative symptoms. Measures were compared between surgeries evaluated by routine postoperative MRA versus routine postoperative angiograms. For each surgery, we determined the ratios of the diameters and areas of the donor and contralateral corresponding vessels and the relative signal intensities of these two vessels on preoperative- and 3-to-30-month postoperative MRA. We did the same for the middle meningeal artery (MMA) ipsilateral to the donor artery and the contralateral MMA. We assessed changes from pre- to post-operation in diameter ratios, area ratios, relative signal intensity, ivy sign, and brain perfusion on arterial spin labeled (ASL) imaging. MRI and MRA measures of revascularization and flow were compared to Matsushima grades in patients who had postoperative catheter angiograms. RESULTS: Fifty-one operations were included. There were no significant differences in rates of strokes, TIAs, changes or new symptoms after surgeries evaluated by routine postoperative MRA versus catheter angiogram. Significant associations existed between greater collateralization on postoperative MRA and greater median increases in preoperative-to-postoperative ratios of donor-vessel-over-contralateral-vessel diameter (p=0.0461) and ipsilateral-MMA-over-contralateral-MMA diameter (p=0.0135). The median increase in the ratio of the donor-vessel-over-corresponding-contralateral-vessel diameters was significantly higher for Matsushima grade A versus B (p=0.036). The median increase in the ratio of the sum of donor-and-ipsilateral-MMA diameters over the sum of the contralateral vessel diameters was significantly higher for improved-versus-unchanged perfusion on ASL imaging (p=0.0074). There was a nonsignificant association between greater postoperative collateralization on MRA and Matsushima grade (p=0.1160) Conclusion: Cerebral revascularization after EDAS/pial synangiosis can be evaluated on axial MRA by comparing the diameter and/or signal intensity of the donor vessel and ipsilateral MMA to those of the corresponding contralateral vessels on postoperative-versus-preoperative MRA. The use of routine postoperative MRA rather than catheter angiography does not appear to negatively affect outcomes.

2.
Cureus ; 16(3): e56575, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38646238

ABSTRACT

Moyamoya arteriopathy is a condition where chronic, progressive stenosis of large intracranial arteries, primarily of the anterior circulation, results in ischemia and the growth of small, abnormal collateral vessels. There is increasing evidence that infectious pathologies, such as COVID-19, may serve as a sort of trigger, or "second hit," for the development of moyamoya arteriopathy. In this article, we present the case of a 13-year-old female with Down syndrome and unilateral moyamoya arteriopathy who developed contralateral internal carotid artery (ICA) dissection and thrombus in the setting of a positive COVID-19 test and subsequently developed rapidly progressive contralateral ICA and bilateral anterior cerebral artery (ACA) moyamoya-like stenosis. The rapidly progressive contralateral ICA and bilateral ACA moyamoya-like stenosis are likely multifactorial in nature. The contralateral ICA may have had a predisposition for injury and stenosis due to the preexisting moyamoya arteriopathy, making stenosis more likely after COVID-19-induced vascular inflammation and injury as well as after a possible thrombectomy-associated injury. Based on this presentation, patients with moyamoya arteriopathy may be at risk for rapid progression of their moyamoya pathology when exposed to catalysts, including infection, such as COVID-19, and vascular injury, such as thrombectomy-induced injury. In these circumstances, high suspicion and close monitoring are essential for addressing ischemia related to the stenosis before permanent injury.

3.
Soc Psychiatry Psychiatr Epidemiol ; 59(4): 599-609, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37624465

ABSTRACT

PURPOSE: To examine within-individual time trends in mental well-being and factors influencing heterogeneity of these trends. METHODS: Longitudinal telephone survey of adults over 3 waves from the New York City (NYC) Metropolitan area during the COVID-19 Pandemic. Participants reported depression using the Patient Health Questionnaire (PHQ)-8, anxiety using the Generalized Anxiety Disorder (GAD)-7, and past 30-day increases in tobacco or alcohol use at each wave. Adjusted mixed effects logistic regression models assessed time trends in mental well-being. RESULTS: There were 1227 respondents. Over 3 study waves, there were statistically significant decreasing time trends in the odds of each outcome (adjusted OR (95% CI) 0.47 (0.37, 0.60); p < 0.001 for depression; aOR (95% CI) 0.55 (0.45, 0.66); p < 0.001 for anxiety; aOR (95% CI) 0.50 (0.35, 0.71); p < 0.001 for past 30-day increased tobacco use; aOR (95% CI) 0.31 (0.24, 0.40); p < 0.001 for past 30-day increased alcohol use). Time trends for anxiety varied by race and ethnicity (p value for interaction = 0.05, 4 df); anxiety declined over time among white, Black, Hispanic, and Other race and ethnicity but not among Asian participants. CONCLUSIONS: In a demographically varied population from the NYC Metropolitan area, depression, anxiety and increased substance use were common during the first months of the pandemic, but decreased over the following year. While this was consistently the case across most demographic groups, the odds of anxiety among Asian participants did not decrease over time.


Subject(s)
Asian , COVID-19 , Adult , Humans , Pandemics , Anxiety/epidemiology , Anxiety Disorders/epidemiology
4.
Mycorrhiza ; 33(3): 139-152, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37165145

ABSTRACT

Current literature suggests ecological niche differentiation between co-occurring Mucoromycotinian arbuscular mycorrhizal fungi (M-AMF) and Glomeromycotinian AMF (G-AMF), but experimental evidence is limited. We investigated the influence of soil age, water availability (wet and dry), and plant species (native Microlaena stipoides and exotic Trifolium subterraneum) on anatomical root colonisation and DNA profiles of M-AMF and G-AMF under glasshouse conditions. We grew seedlings of each species in soils collected from the four stages of a soil chronosequence, where pH decreases from the youngest to oldest stages, and phosphorus (P) is low in the youngest and oldest, but high in the intermediate stages. We scored the percentage of root length colonised and used DNA metabarcoding to profile fungal richness and community composition associated with treatment combinations. Soil age, water availability, and plant species were important influencers of root colonisation, although no M-AMF were visible following staining of M. stipoides roots. Soil age and host plant influenced fungal richness and community composition. However, response to soil age, potential host species, and water availability differed between M-AMF and G-AMF. Root colonisation of T. subterraneum by M-AMF and G-AMF was inversely correlated with soil P level. Community composition of M-AMF and G-AMF was structured by soil age and, to a lesser extent, plant species. Richness of M-AMF and G-AMF was negatively, and positively, correlated with available P, respectively. These findings are experimental evidence of ecological niche differentiation of M-AMF and G-AMF and invite further exploration into interactive effects of abiotic and biotic factors on their communities along successional trajectories.


Subject(s)
Mycorrhizae , Mycorrhizae/physiology , Soil/chemistry , Plant Roots/microbiology , Ecosystem , Water , Soil Microbiology , Fungi/physiology
5.
eNeuro ; 10(5)2023 05.
Article in English | MEDLINE | ID: mdl-37185294

ABSTRACT

Autism spectrum disorder (ASD) is a common neurodevelopmental condition for which there are no pharmacological therapies that effectively target its core symptomatology. Animal models of syndromic forms of ASD, such as neurofibromatosis type 1, may be of use in screening for such treatments. Drosophila larvae lacking Nf1 expression exhibit tactile hypersensitivity following mechanical stimulation, proposed to mirror the sensory sensitivity issues comprising part of the ASD diagnostic criteria. Such behavior is associated with synaptic dysfunction at the neuromuscular junction (NMJ). Both phenotypes may thus provide tractable outputs with which to screen for potential ASD therapies. In this study, we demonstrate that, while loss of Nf1 expression within the embryo is sufficient to impair NMJ synaptic transmission in the larva, constitutive Nf1 knock-down is required to induce tactile hypersensitivity, suggesting that a compound must be administered throughout development to rescue this behavior. With such a feeding regime, we identify two compounds from a targeted, low-throughput screen that significantly and consistently reduce, but do not fully rescue, tactile hypersensitivity in Nf1P1 larvae. These are the HMG CoA-reductase inhibitor simvastatin, and the BKCa channel activator BMS-204352. At the NMJ, both compounds induce a significant reduction in the enhanced spontaneous transmission frequency of Nf1P1 larvae, though again not to the level of vehicle-treated controls. However, both compounds fully rescue the increased quantal size of Nf1P1 mutants, with simvastatin also fully rescuing their reduced quantal content. Thus, the further study of both compounds as potential ASD interventions is warranted.


Subject(s)
Autism Spectrum Disorder , Neurofibromatosis 1 , Animals , Neurofibromatosis 1/complications , Neurofibromatosis 1/diagnosis , Autism Spectrum Disorder/genetics , Simvastatin/pharmacology , Simvastatin/therapeutic use , Drosophila
6.
Funct Plant Biol ; 50(6): 507-518, 2023 06.
Article in English | MEDLINE | ID: mdl-37142401

ABSTRACT

The isoflavone formononetin (F) impacts livestock fertility and cultivars of the pasture legume Trifolium subterraneum L. (subclover) have been selected for F levels ≤0.2% of leaf dry weight. However, the impact of waterlogging (WL) on isoflavones is little studied. We investigated the response of isoflavones, biochanin A (BA), genistein (G) and F, to WL for: (1) Yarloop (high F) and eight low F cultivars each from subspecies subterraneum , brachycalycinum and yanninicum (Experiment 1); and (2) four cultivars and 12 ecotypes of ssp. yanninicum (Experiment 2). WL impacted F: estimated means increased from 0.19% (control) to 0.31% (WL) in Experiment 1 and from 0.61% to 0.97% in Experiment 2. Isoflavones under WL were highly heritable, particularly F (H 2 =95%). The proportions of BA, G and F were little changed by WL, with strong positive correlations between free-drained and waterlogged treatments. Isoflavone contents were not related to WL tolerance, as assessed by shoot relative growth rate. In conclusion, isoflavones varied among genotypes and increased with WL, but the proportion of individual isoflavones in each genotype was stable. High F under WL was unrelated with genotype tolerance to WL. Instead, it was a consequence of inherently high F for that particular genotype.


Subject(s)
Fabaceae , Isoflavones , Trifolium , Plant Leaves
7.
Article in English | MEDLINE | ID: mdl-37174153

ABSTRACT

The purpose of this study was to investigate the association between personal religiosity, mental health, and substance use outcomes among Black and Hispanic adults during the first six months of the COVID-19 outbreak in New York City (NYC). Phone interviews were conducted with 441 adults to obtain information on all variables. Participants self-reported race/ethnicity as Black/African American (n = 108) or Hispanic (n = 333). Logistic regression were used to examine associations between religiosity, mental health, and substance use. There was a significant inverse association of religiosity and substance use. Religious people had a lower prevalence of drinking alcohol (49.0%) compared to non-religious people (67.1%). Religious people also had substantially lower prevalence of cannabis or other drug use (9.1%) in comparison to non-religious people (31%). After adjusting for age, sex, race/ethnicity, and household income, the association of religiosity with alcohol use and with cannabis/other drug use remained statistically significant. Despite restricted access to in-person religious activities and congregational supports, the findings suggest that religiosity itself may be helpful from a public health perspective, independent of serving as a conduit for other social services.


Subject(s)
COVID-19 , Substance-Related Disorders , Adult , Humans , COVID-19/epidemiology , Hispanic or Latino/psychology , Mental Health , New York City/epidemiology , Pandemics , Religion , Substance-Related Disorders/epidemiology , Black or African American
8.
Public Health Rep ; 138(3): 518-525, 2023.
Article in English | MEDLINE | ID: mdl-36905312

ABSTRACT

OBJECTIVES: The COVID-19 Healthcare Personnel Study is a longitudinal survey to assess the changing impact of the COVID-19 pandemic on the New York State health care workforce. We analyzed results from a follow-up survey of physicians, nurse practitioners, and physician assistants on the availability of equipment and personnel, work conditions, physical and mental health of participants, and impact of the pandemic on commitment to their profession. METHODS: We conducted an online survey of all licensed New York State physicians, nurse practitioners, and physician assistants in April 2020 (N = 2105) and a follow-up survey in February 2021 (N = 978). We analyzed changes in item responses from baseline to follow-up. We calculated survey-adjusted paired t tests and odds ratios (ORs) using survey-adjusted generalized linear models controlling for age, sex, region of practice, and hospital versus non-hospital-based practice. RESULTS: Twenty percent of respondents expressed continuing concern about personnel shortages at both baseline and follow-up. Respondents reported working approximately 5 more hours on average during a 2-week period at follow-up compared with baseline (78.1 vs 72.6 hours; P = .008). For 20.4% (95% CI, 17.2%-23.5%) of respondents, mental health issues had become persistent. More than one-third (35.6%; 95% CI, 31.9%-39.4%) of respondents reported that they thought about leaving their profession more often than once per month. The association between persistent mental and behavioral health issues and contemplating leaving one's profession was significant (OR = 2.7; 95% CI, 1.8-4.1; P < .001). CONCLUSIONS: Interventions such as decreasing the number of hours worked, ensuring health care professionals do not work directly with patients while ill, and addressing shortages of personal protective equipment can help address concerns of the health care workforce.


Subject(s)
COVID-19 , Nurse Practitioners , Physician Assistants , Physicians , Humans , New York/epidemiology , COVID-19/epidemiology , Follow-Up Studies , Pandemics , Health Personnel , Surveys and Questionnaires , Delivery of Health Care
9.
J Craniofac Surg ; 34(3): 969-975, 2023 May 01.
Article in English | MEDLINE | ID: mdl-36939862

ABSTRACT

INTRODUCTION: After treating a child with familial sagittal craniosynostosis, clinocephaly, and bilateral parietomastoid/posterior squamosal suture fusion, the authors wondered if major-suture synostosis and clinocephaly were associated with abnormal fusion of minor lateral calvarial sutures. METHODS: The authors reviewed all preoperative volume-rendered head computed tomography reconstructions performed for craniosynostosis at their institution from 2010 through 2014 and determined whether the sphenoparietal, squamosal, and parietomastoid sutures were open, partially fused, or fused. The authors determined whether any sutures were abnormally fused based upon a previous study from their center, in which abnormal fusion was defined as either 1 of 3 abnormal fusion patterns or abnormally-early fusion. The authors then determined the rate of abnormal fusion of these sutures and whether abnormal fusion was associated with (1) major-suture craniosynostosis, (2) type of craniosynostosis (sutures involved; single-suture versus multisuture; syndromic versus nonsyndromic), and (3) clinocephaly. RESULTS: In 97 included children, minor lateral sutures were abnormally fused in 8, or 8.2%, which was significantly higher than in children without craniosynostosis from our earlier study. Abnormal minor lateral suture fusion was not associated with the type of single-suture synostosis or with multisuture synostosis but was associated with syndromic synostosis. Four of 8 children with abnormal minor lateral suture fusion had multisuture synostosis and 6 had syndromic synostosis. Lateral sutures were abnormally fused in 1 of 4 subjects with clinocephaly, which was not significant. CONCLUSION: Abnormal minor lateral calvarial suture fusion is significantly associated with major-suture craniosynostosis, especially syndromic synostosis.


Subject(s)
Craniosynostoses , Plastic Surgery Procedures , Child , Humans , Infant , Craniosynostoses/diagnostic imaging , Craniosynostoses/surgery , Cranial Sutures/diagnostic imaging , Cranial Sutures/surgery , Tomography, X-Ray Computed , Sutures
10.
Pediatr Neurosurg ; 58(2): 105-113, 2023.
Article in English | MEDLINE | ID: mdl-36809759

ABSTRACT

INTRODUCTION: Encephaloduroarteriosynangiosis (EDAS) for moyamoya is predominantly performed using a branch of the superficial temporal artery (STA) as the donor artery. At times, other branches of the external carotid artery are better suited for EDAS than is the STA. There is little information in the literature concerning using the posterior auricular artery (PAA) for EDAS in the pediatric age-group. In this case series, we review our experience using the PAA for EDAS in children and adolescents. CASE PRESENTATIONS: We describe the presentations, imaging, and outcomes of 3 patients in whom the PAA was used for EDAS, as well our surgical technique. There were no complications. All 3 patients were confirmed to have radiologic revascularization from their surgeries. All patients also had improvement of their preoperative symptoms, and no patient has had a stroke postoperatively. CONCLUSION: The PAA is a viable option for use as a donor artery in EDAS for the treatment of moyamoya in children and adolescents.


Subject(s)
Cerebral Revascularization , Moyamoya Disease , Stroke , Adolescent , Child , Humans , Arteries/surgery , Cerebral Revascularization/methods , Moyamoya Disease/diagnostic imaging , Moyamoya Disease/surgery , Stroke/etiology , Treatment Outcome
11.
Reproduction ; 165(4): 445-456, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36757297

ABSTRACT

In brief: Dietary phytoestrogens disrupt a specific stage of ram spermatogenesis, causing subtle decreases in sperm quality by affecting the expression of pathways involved in the structural integrity of the spermatozoa. This paper demonstrates for the first time that ram reproduction is compromised by oestrogenic pasture, whilst also providing a longitudinal model for the impact of phytoestrogens on male fertility. Abstract: Compounds with oestrogen-like actions are now common in both the Western diet. The long-term impacts and underlying mechanisms by which oestrogenic compounds alter male reproduction, however, are unclear. To investigate this, we used a longitudinal sheep model examining the impact of oestrogenic pasture consumption on semen quality and production, testicular size, sexual behaviour and the seminal plasma proteome of Merino rams (n = 20), over a full spermatogenic cycle and in the subsequent breeding season. Throughout the study period, sexual behaviour, sperm production and motility were similar between the exposed and non-exposed rams (P > 0.05). However, between 5 and 8 weeks of exposure to dietary phytoestrogens, rams produced a higher percentage of spermatozoa with a specific malformation of the sperm midpiece and reduced DNA integrity, compared to non-exposed rams (P < 0.001). Investigation into the seminal plasma proteome revealed 93 differentially expressed proteins between phytoestrogen-exposed and control rams (P < 0.05). Exposure to phytoestrogens increased the expression of proteins involved in cellular structure development, actin cytoskeleton reorganisation, regulation of cell function and decreased expression in those related to catabolic processes. The greatest fold changes were in proteins involved in the assembly of the sperm flagella, removal of cytoplasm, spermatid development and maintenance of DNA integrity. After returning to non-oestrogenic pasture, no differences in any measure were observed between treatment groups during the subsequent breeding season. We conclude that dietary phytoestrogens can transiently disrupt specific stages of ram spermatogenesis, causing subtle decreases in sperm quality by affecting the expression of pathways involved in the structural integrity of the spermatozoa.


Subject(s)
Phytoestrogens , Semen , Male , Sheep , Animals , Semen/metabolism , Phytoestrogens/pharmacology , Semen Analysis/veterinary , Proteome/analysis , Spermatozoa/physiology , Spermatogenesis , Sheep, Domestic , Sperm Motility/physiology
12.
Physiol Plant ; 175(2): e13873, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36762694

ABSTRACT

The coordination/trade-off among below-ground strategies for phosphorus (P) acquisition, including root morphology, carboxylate exudation and colonisation by arbuscular mycorrhizal fungi (AMF), is not well understood. This is the first study investigating the relationships between root nodulation, morphology, carboxylates and colonisation by an indigenous community of AMF under varying P levels and source. Two chickpea genotypes with contrasting amounts of rhizosheath carboxylates were grown in pots at six P levels (from 0 to 160 µg g-1 ) as KH2 PO4 (KP, highly soluble) or FePO4 (FeP, sparingly soluble), with or without AMF (±AMF) treatment. Under both FeP and KP, the presence of AMF inhibited shoot growth and shoot branching, decreased total root length and specific root length, increased mean root diameter and root tissue density and reduced carboxylates. However, the role of AMF in acquiring P differed between the two P sources, with the enhanced P acquisition under FeP while not under KP. Co-inoculation of AMF and rhizobia enhanced nodulation under FeP, but not under KP. Our results suggest that the effects of AMF on shoot branching were mediated by cytokinins as the reduced shoot branching in FeP40 and KP40 under +AMF relative to -AMF coincided with a decreased concentration of cytokinins in xylem sap for both genotypes.


Subject(s)
Cicer , Mycorrhizae , Phosphorus , Plant Roots , Phosphates , Iron
13.
J Soc Psychol ; 163(6): 789-805, 2023 Nov 02.
Article in English | MEDLINE | ID: mdl-35137678

ABSTRACT

Authoritarianism emerges in times of societal threat, in part driven by desires for group-based security. As such, we propose that the threat caused by the COVID-19 pandemic was associated with increased authoritarian tendencies and that this can be partially explained by increased national identification. We tested this hypothesis by collecting cross-sectional data from three different countries in April 2020. In Study 1, data from Ireland (N = 1276) showed that pandemic threat predicted increased national identification, which in turn predicted authoritarianism. In Study 2, we replicated this indirect effect in a representative UK sample (N = 506). In Study 3, we used an alternative measure of authoritarianism and conceptually replicated this effect among USA citizens (N = 429). In this US sample, the association between threat and authoritarian tendencies was stronger among progressives compared to conservatives. Findings are discussed and linked to group-based models of authoritarianism.


Subject(s)
COVID-19 , Pandemics , Humans , Authoritarianism , Social Cohesion , Cross-Sectional Studies , Politics
14.
J Exp Bot ; 74(6): 1974-1989, 2023 03 28.
Article in English | MEDLINE | ID: mdl-36575916

ABSTRACT

Although significant intraspecific variation in photosynthetic phosphorus (P) use efficiency (PPUE) has been shown in numerous species, we still know little about the biochemical basis for differences in PPUE among genotypes within a species. Here, we grew two high PPUE and two low PPUE chickpea (Cicer arietinum) genotypes with low P supply in a glasshouse to compare their photosynthesis-related traits, total foliar P concentration ([P]) and chemical P fractions (i.e. inorganic P (Pi), metabolite P, lipid P, nucleic acid P, and residual P). Foliar cell-specific nutrient concentrations including P were characterized using elemental X-ray microanalysis. Genotypes with high PPUE showed lower total foliar [P] without slower photosynthetic rates. No consistent differences in cellular [P] between the epidermis and mesophyll cells occurred across the four genotypes. In contrast, high PPUE was associated with lower allocation to Pi and metabolite P, with PPUE being negatively correlated with the percentage of these two fractions. Furthermore, a lower allocation to Pi and metabolite P was correlated with a greater allocation to nucleic acid P, but not to lipid P. Collectively, our results suggest that a different allocation to foliar P fractions, rather than preferential P allocation to specific leaf tissues, underlies the contrasting PPUE among chickpea genotypes.


Subject(s)
Cicer , Phosphorus , Phosphorus/metabolism , Cicer/genetics , Plant Leaves/metabolism , Photosynthesis , Genotype , Lipids/analysis
15.
New Phytol ; 237(4): 1122-1135, 2023 02.
Article in English | MEDLINE | ID: mdl-36328763

ABSTRACT

Leaf phosphorus (P) comprises four major fractions: inorganic phosphate (Pi ), nucleic acids, phospholipids, P-containing metabolites and a residual fraction. In this review paper, we investigated whether allocation of P fractions varies among groups of terrestrial vascular plants, and is indicative of a species' strategy to use P efficiently. We found that as leaf total P concentration increases, the Pi fraction increases the most, without a plateau, while other fractions plateau. Variability of the concentrations of leaf P fractions is greatest among families > species(family) > regions > plant life forms. The percentage of total P allocated to nucleic acid-P (20-35%) and lipid-P (14-34%) varies less among families/species. High photosynthetic P-use efficiency is associated with low concentrations of all P fractions, and preferential allocation of P to metabolite-P and mesophyll cells. Sequential resorption of P from senescing leaves starts with Pi , followed by metabolite-P, and then other organic P fractions. Allocation of P to leaf P fractions varies with season. Leaf phytate concentrations vary considerably among species, associated with variation in photosynthesis and defence. Plasticity of P allocation to its fractions is important for acclimation to low soil P availability, and species-specific P allocation is needed for co-occurrence with other species.


Subject(s)
Phosphorus , Plant Leaves , Phosphorus/metabolism , Plant Leaves/metabolism , Mesophyll Cells/metabolism , Phosphates/metabolism , Soil , Photosynthesis
16.
J Neurosci ; 42(50): 9450-9472, 2022 12 14.
Article in English | MEDLINE | ID: mdl-36344265

ABSTRACT

Autism spectrum disorder (ASD) is a neurodevelopmental condition in which the mechanisms underlying its core symptomatology are largely unknown. Studying animal models of monogenic syndromes associated with ASD, such as neurofibromatosis type 1 (NF1), can offer insights into its etiology. Here, we show that loss of function of the Drosophila NF1 ortholog results in tactile hypersensitivity following brief mechanical stimulation in the larva (mixed sexes), paralleling the sensory abnormalities observed in individuals with ASD. Mutant larvae also exhibit synaptic transmission deficits at the glutamatergic neuromuscular junction (NMJ), with increased spontaneous but reduced evoked release. While the latter is homeostatically compensated for by a postsynaptic increase in input resistance, the former is consistent with neuronal hyperexcitability. Indeed, diminished expression of NF1 specifically within central cholinergic neurons induces both excessive neuronal firing and tactile hypersensitivity, suggesting the two may be linked. Furthermore, both impaired synaptic transmission and behavioral deficits are fully rescued via knock-down of Ras proteins. These findings validate NF1 -/- Drosophila as a tractable model of ASD with the potential to elucidate important pathophysiological mechanisms.SIGNIFICANCE STATEMENT Autism spectrum disorder (ASD) affects 1-2% of the overall population and can considerably impact an individual's quality of life. However, there are currently no treatments available for its core symptoms, largely because of a poor understanding of the underlying mechanisms involved. Examining how loss of function of the ASD-associated NF1 gene affects behavior and physiology in Drosophila may shed light on this. In this study, we identify a novel, ASD-relevant behavioral phenotype in NF1 -/- larvae, namely an enhanced response to mechanical stimulation, which is associated with Ras-dependent synaptic transmission deficits indicative of neuronal hyperexcitability. Such insights support the use of Drosophila neurofibromatosis type 1 (NF1) models in ASD research and may provide outputs for genetic or pharmacological screens in future studies.


Subject(s)
Autism Spectrum Disorder , Drosophila Proteins , Neurofibromatosis 1 , Animals , Drosophila/metabolism , Larva/metabolism , Quality of Life , Neuromuscular Junction/metabolism , Synaptic Transmission/genetics , Drosophila Proteins/genetics , Drosophila Proteins/metabolism
17.
Psychol Trauma ; 2022 Oct 10.
Article in English | MEDLINE | ID: mdl-36222664

ABSTRACT

OBJECTIVE: Childhood trauma is linked to the dysregulation of physiological responses to stress, particularly lower cardiovascular reactivity (CVR) to acute stress. The mechanisms that explain this association, however, are not yet fully understood. METHOD: Using secondary data from the Midlife in the United States (MIDUS) Biomarker Project (N = 1,148; n = 652 females), we examine whether social integration can help explain the association between childhood trauma and lower CVR. Participants completed a standardized laboratory stress paradigm which involved completing executive functioning (Stroop) and mental arithmetic (MATH) tasks. Cardiovascular measurements were continuously assessed using electrocardiogram (ECG) and Finometer equipment. The Social Well-Being Scale (Keyes, 1998) and the Childhood Trauma Questionnaire (CTQ; Bernstein et al., 2003) measured social integration and trauma, respectively. RESULTS: Regression analyses demonstrated that childhood trauma was associated with lower systolic (SBP; ß = -.14, p < .001) and diastolic (DBP; ß = -.11, p < .001) blood pressure reactivity but not heart rate (HR) reactivity. Mediation analyses, using Hayes PROCESS Model 4, showed that higher levels of trauma were associated with less social integration and in turn linked to lower reactivity across all biological indices. Moreover, sensitivity analyses showed that this indirect effect via social integration was evident for emotional and physical abuse, emotional and physical neglect, but not sexual abuse. CONCLUSION: Overall, the results indicated that dysregulated cardiovascular stress responses owing to childhood trauma may be shaped by a lack of social integration. The implications of this, as well as the findings for the individual types of trauma, are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

18.
AoB Plants ; 14(5): plac037, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36196393

ABSTRACT

Many plant species from regions with ancient, highly weathered nutrient-depleted soils have specialized adaptations for acquiring phosphorus (P) and are sensitive to excess P supply. Mycorrhizal associations may regulate P uptake at high external P concentrations, potentially reducing P toxicity. We predicted that excess P application will negatively impact species from the nutrient-depleted Jarrah forest of Western Australia and that mycorrhizal inoculation will reduce P toxicity by regulating P uptake. For seedlings of the N2-fixing legume Acacia celastrifolia and the tree species Eucalyptus marginata, we measured growth at P concentrations of 0-90 mg kg-1 soil and in relation to inoculation with the arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis. Non-inoculated A. celastrifolia maintained leaf P concentrations at <2 mg g-1 dry mass (DM) across the range of external P concentrations. However, for non-inoculated E. marginata, as external P concentrations increased, leaf P also increased, reaching >9 mg g-1 DM at 30 mg P kg-1 soil. Acacia celastrifolia DM increased with increasing external P concentrations, while E. marginata DM was maximal at 15 mg P kg-1 soil, declining at higher external P concentrations. Neither DM nor leaf P of A. celastrifolia was affected by inoculation with AMF. For E. marginata, even at 90 mg P kg-1 soil, inoculation with AMF resulted in leaf P remaining <1 mg g-1 DM, and DM being maintained. These data strengthen the evidence base that AMF may not only facilitate P uptake at low external P concentrations, but are also important for moderating P uptake at elevated external P concentrations and maintaining plant P concentrations within a relatively narrow concentration range.

19.
Soc Sci Med ; 311: 115359, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36126475

ABSTRACT

RATIONALE: The slow and insidious effects of income inequality on health means that their effects can be difficult to reveal, taking many years to become apparent. These effects can also be experienced differently according to subjective status and ethnicity making the relation between income inequality and health difficult to understand. Cardiovascular reactions to acute stress are indicative of future health outcomes. OBJECTIVE: To examine whether short to medium term income inequality affected cardiovascular responses to acute stress whilst accounting for ethnic groups and subjective status. METHOD: Participants state of residence was available for 1155 people who participated in the MIDUS biomarker data project. This detail was used to merge the relevant US state level inequality data 1, 5, 10 and 15 years prior to the MIDUS biomarker data project which assessed cardiovascular responses to acute stress. RESULTS: Our analysis demonstrated an association between inequality 5, 10 and 15 year prior and cardiovascular reactions to acute stress. Subjective community status and Black and minority ethnic group membership interacted to affect the association between inequality and cardiovascular reactions. CONCLUSIONS: In states where income inequality was high, less healthy cardiovascular responses were evident. However lower subjective community status and Black and Ethnic minority group members interacted with income inequality such that their impact was variable contingent on state level inequality. These findings extend the literature on income inequality and health and particularly highlights a psychophysiology pathway linking income inequality and health.

20.
J Pediatr Rehabil Med ; 15(2): 377-381, 2022.
Article in English | MEDLINE | ID: mdl-35661026

ABSTRACT

Selective dorsal rhizotomy (SDR) was used to treat lower extremity spasticity in an ambulatory 7-year-old girl with a history of a T10 spinal lipoma. The spasticity was the result of an AIS D spinal cord injury (SCI) suffered during untethering surgery at age 2 years. After SDR and a course of intensive inpatient rehabilitation, the patient's gait improved markedly. To the authors' knowledge, this is the first published case of SDR as a treatment for spasticity in a patient with a spinal lipomatous malformation.


Subject(s)
Cerebral Palsy , Lipoma , Spinal Cord Injuries , Cerebral Palsy/complications , Child , Child, Preschool , Female , Gait , Humans , Lipoma/complications , Lipoma/surgery , Muscle Spasticity/etiology , Muscle Spasticity/surgery , Rhizotomy , Spinal Cord Injuries/complications , Treatment Outcome
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