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Phosphorus (P) has long been recognized as an essential input for plant and animal production. Dramatic improvements in the economic efficiency of grain and animal protein production over the last [...]

A recently introduced rapid petrophysical wireline evaluation has been tested and demonstrated to provide accurate petrophysical answers in a deepwater Gulf of Mexico well. This new interpretation scheme uses the combination of elemental concentrations from nuclear capture spectroscopy logs and standard neutron, density, resistivity, or "triple-combo" log measurements to get a more accurate description of the lithology and matrix parameters. Of particular value in the interpretation are the straightforward computation of matrix density from elemental concentrations and the resulting accurate porosity. Accurate clay and porosity values combine to provide a good estimate of permeability. These are all integrated with resistivity logs to estimate water saturation and irreducible water saturation to complete the petrophysical interpretation (Herron et al. 2002). In this study, the rapid petrophysical evaluations of porosity, permeability, and irreducible water saturation are demonstrated to agree well with core data. Initial disagreement between the interpreted lithology and core data jeopardized future use of the new interpretation, but on further investigation, the discrepancies were proved to be caused by the core measurements, not the wireline data. Therefore, part of the study focuses on the reanalysis and evaluation of core samples. [ABSTRACT FROM AUTHOR]

Background: Despite high rates of cardiovascular disease in Scotland, the prevalence and outcomes of patients with cardiogenic shock are unknown., Methods: We undertook a prospective observational cohort study of consecutive patients with cardiogenic shock admitted to the intensive care unit (ICU) or coronary care unit at 13 hospitals in Scotland for a 6-month period. Denominator data from the Scottish Intensive Care Society Audit Group were used to estimate ICU prevalence; data for coronary care units were unavailable. We undertook multivariable logistic regression to identify factors associated with in-hospital mortality., Results: In total, 247 patients with cardiogenic shock were included. After exclusion of coronary care unit admissions, this comprised 3.0% of all ICU admissions during the study period (95% confidence interval [CI] 2.6%-3.5%). Aetiology was acute myocardial infarction (AMI) in 48%. The commonest vasoactive treatment was noradrenaline (56%) followed by adrenaline (46%) and dobutamine (40%). Mechanical circulatory support was used in 30%. Overall in-hospital mortality was 55%. After multivariable logistic regression, age (odds ratio [OR] 1.04, 95% CI 1.02-1.06), admission lactate (OR 1.10, 95% CI 1.05-1.19), Society for Cardiovascular Angiographic Intervention stage D or E at presentation (OR 2.16, 95% CI 1.10-4.29) and use of adrenaline (OR 2.73, 95% CI 1.40-5.40) were associated with mortality., Conclusions: In Scotland the prevalence of cardiogenic shock was 3% of all ICU admissions; more than half died prior to discharge. There was significant variation in treatment approaches, particularly with respect to vasoactive support strategy., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Intensive Care Society 2023.)

The APOE4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease (AD). The contribution of microglial APOE4 to AD pathogenesis is unknown, although APOE has the most enriched gene expression in neurodegenerative microglia (MGnD). Here, we show in mice and humans a negative role of microglial APOE4 in the induction of the MGnD response to neurodegeneration. Deletion of microglial APOE4 restores the MGnD phenotype associated with neuroprotection in P301S tau transgenic mice and decreases pathology in APP/PS1 mice. MGnD-astrocyte cross-talk associated with β-amyloid (Aβ) plaque encapsulation and clearance are mediated via LGALS3 signaling following microglial APOE4 deletion. In the brains of AD donors carrying the APOE4 allele, we found a sex-dependent reciprocal induction of AD risk factors associated with suppression of MGnD genes in females, including LGALS3, compared to individuals homozygous for the APOE3 allele. Mechanistically, APOE4-mediated induction of ITGB8-transforming growth factor-β (TGFβ) signaling impairs the MGnD response via upregulation of microglial homeostatic checkpoints, including Inpp5d, in mice. Deletion of Inpp5d in microglia restores MGnD-astrocyte cross-talk and facilitates plaque clearance in APP/PS1 mice. We identify the microglial APOE4-ITGB8-TGFβ pathway as a negative regulator of microglial response to AD pathology, and restoring the MGnD phenotype via blocking ITGB8-TGFβ signaling provides a promising therapeutic intervention for AD., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Microglia play a critical role in brain homeostasis and disease progression. In neurodegenerative conditions, microglia acquire the neurodegenerative phenotype (MGnD), whose function is poorly understood. MicroRNA-155 (miR-155), enriched in immune cells, critically regulates MGnD. However, its role in Alzheimer's disease (AD) pathogenesis remains unclear. Here, we report that microglial deletion of miR-155 induces a pre-MGnD activation state via interferon-γ (IFN-γ) signaling, and blocking IFN-γ signaling attenuates MGnD induction and microglial phagocytosis. Single-cell RNA-sequencing analysis of microglia from an AD mouse model identifies Stat1 and Clec2d as pre-MGnD markers. This phenotypic transition enhances amyloid plaque compaction, reduces dystrophic neurites, attenuates plaque-associated synaptic degradation and improves cognition. Our study demonstrates a miR-155-mediated regulatory mechanism of MGnD and the beneficial role of IFN-γ-responsive pre-MGnD in restricting neurodegenerative pathology and preserving cognitive function in an AD mouse model, highlighting miR-155 and IFN-γ as potential therapeutic targets for AD., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Numerous approaches have been developed to isolate microglia from the brain, but procedures using enzymatic dissociation at 37°C can introduce drastic transcriptomic changes and confound results from gene expression assays. Here, we present an optimized protocol for microglia isolation using mechanical homogenization. We use Dounce homogenization to homogenize mouse brain tissue into single-cell suspension. We then isolate microglia through Percoll gradient and flow cytometry. Isolated microglia exhibit a gene expression pattern without the changes induced by heated enzymatic digestion. For complete details on the use and execution of this protocol, please refer to Clayton et al. (2021)., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Single cell RNA sequencing studies identified novel neurodegeneration-associated microglial (MGnD/DAM) subtypes activated around cerebral amyloid plaques. Micro-RNA (miR)-155 of the TREM2-APOE pathway was shown to be a key transcriptional regulator of MGnD microglial phenotype. Despite growing interest in studying manifestations of Alzheimer's disease (AD) in the retina, a CNS organ accessible to noninvasive high-resolution imaging, to date MGnD microglia have not been studied in the AD retina. Here, we discovered the presence and increased populations of Clec7a + and Galectin-3 + MGnD microglia in retinas of transgenic APP SWE /PS1 L166P AD-model mice. Conditionally targeting MGnD microglia by miR-155 ablation via the tamoxifen-inducible Cre ERT2 system in APP SWE /PS1 L166P mice diminished retinal Clec7a + and Galectin-3 + microglial populations while increasing homeostatic P2ry12 + microglia. Retinal MGnD microglia were often adhering to microvessels; their depletion protected the inner blood-retina barrier and reduced vascular amyloidosis. Microglial miR-155 depletion further limits retinal inflammation. Mass spectrometry analysis revealed enhanced retinal PI3K-Akt signaling and predicted IL-8 and Spp1 decreases in mice with microglia-specific miR-155 knockout. Overall, this study identified MGnD microglia in APP SWE /PS1 L166P mouse retina. Transcriptional regulation of these dysfunctional microglia mitigated retinal inflammation and vasculopathy. The protective effects of microglial miR-155 ablation should shed light on potential treatments for retinal inflammation and vascular damage during AD and other ocular diseases., (© 2022. The Author(s).)

Background: Recent studies suggest that microglia contribute to tau pathology progression in Alzheimer's disease. Amyloid plaque accumulation transforms microglia, the primary innate immune cells in the brain, into neurodegenerative microglia (MGnD), which exhibit enhanced phagocytosis of plaques, apoptotic neurons and dystrophic neurites containing aggregated and phosphorylated tau (p-tau). It remains unclear how microglia promote disease progression while actively phagocytosing pathological proteins, therefore ameliorating pathology., Methods: Adeno-associated virus expressing P301L tau mutant (AAV-P301L-tau) was stereotaxically injected into the medial entorhinal cortex (MEC) in C57BL/6 (WT) and humanized APP mutant knock-in homozygote (App NL-G-F ) mice at 5 months of age. Mice were fed either chow containing a colony stimulating factor-1 receptor inhibitor (PLX5622) or control chow from 4 to 6 months of age to test the effect of microglia depletion. Animals were tested at 6 months of age for immunofluorescence, biochemistry, and FACS of microglia. In order to monitor microglial extracellular vesicle secretion in vivo, a novel lentiviral EV reporter system was engineered to express mEmerald-CD9 (mE-CD9) specifically in microglia, which was injected into the same region of MEC., Results: Expressing P301L tau mutant in the MEC induced tau propagation to the granule cell layer of the hippocampal dentate gyrus, which was significantly exacerbated in App NL-G-F mice compared to WT control mice. Administration of PLX5622 depleted nearly all microglia in mouse brains and dramatically reduced propagation of p-tau in WT and to a greater extent in App NL-G-F mice, although it increased plaque burden and plaque-associated p-tau + dystrophic neurites. Plaque-associated MGnD microglia strongly expressed an EV marker, tumor susceptibility gene 101, indicative of heightened synthesis of EVs. Intracortical injection of mE-CD9 lentivirus successfully induced microglia-specific expression of mE-CD9 + EV particles, which were significantly enhanced in Mac2 + MGnD microglia compared to Mac2 - homeostatic microglia. Finally, consecutive intracortical injection of mE-CD9 lentivirus and AAV-P301L-tau into App NL-G-F mice revealed encapsulation of p-tau in microglia-specific mE-CD9 + EVs as determined by super-resolution microscopy and immuno-electron microscopy., Discussion: Our findings suggest that MGnD microglia hyper-secrete p-tau + EVs while compacting Aβ plaques and clearing NP tau, which we propose as a novel mechanistic link between amyloid plaque deposition and exacerbation of tau propagation in App NL-G-F mice.

Mucolipidosis type IV (MLIV) is a lysosomal disease caused by mutations in the MCOLN1 gene that encodes the endolysosomal transient receptor potential channel mucolipin-1, or TRPML1. MLIV results in developmental delay, motor and cognitive impairments, and vision loss. Brain abnormalities include thinning and malformation of the corpus callosum, white-matter abnormalities, accumulation of undegraded intracellular 'storage' material and cerebellar atrophy in older patients. Identification of the early events in the MLIV course is key to understanding the disease and deploying therapies. The Mcoln1 -/- mouse model reproduces all major aspects of the human disease. We have previously reported hypomyelination in the MLIV mouse brain. Here, we investigated the onset of hypomyelination and compared oligodendrocyte maturation between the cortex/forebrain and cerebellum. We found significant delays in expression of mature oligodendrocyte markers Mag , Mbp and Mobp in the Mcoln1 -/- cortex, manifesting as early as 10 days after birth and persisting later in life. Such delays were less pronounced in the cerebellum. Despite our previous finding of diminished accumulation of the ferritin-bound iron in the Mcoln1 -/- brain, we report no significant changes in expression of the cytosolic iron reporters, suggesting that iron-handling deficits in MLIV occur in the lysosomes and do not involve broad iron deficiency. These data demonstrate very early deficits of oligodendrocyte maturation and critical regional differences in myelination between the forebrain and cerebellum in the mouse model of MLIV. Furthermore, they establish quantitative readouts of the MLIV impact on early brain development, useful to gauge efficacy in pre-clinical trials., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

Accumulation of microtubule associated protein tau in the substantia nigra is associated with several tauopathies including progressive supranuclear palsy (PSP). A number of studies have used mutant tau transgenic mouse model to mimic the neuropathology of tauopathies and disease phenotypes. However, tau expression in these transgenic mouse models is not specific to brain subregions, and may not recapitulate subcortical disease phenotypes of PSP. It is necessary to develop a new disease modeling system for cell and region-specific expression of pathogenic tau for modeling PSP in mouse brain. In this study, we developed a novel strategy to express P301L mutant tau to the dopaminergic neurons of substantia nigra by coupling tyrosine hydroxylase promoter Cre-driver mice with a Cre-inducible adeno-associated virus (iAAV). The results showed that P301L mutant tau was successfully transduced in the dopaminergic neurons of the substantia nigra at the presence of Cre recombinase and iAAV. Furthermore, the iAAV-tau-injected mice displayed severe motor deficits including impaired movement ability, motor balance, and motor coordination compared to the control groups over a short time-course. Immunochemical analysis revealed that tau gene transfer significantly resulted in loss of tyrosine hydroxylase-positive dopaminergic neurons and elevated phosphorylated tau in the substantia nigra. Our development of dopaminergic neuron-specific neurodegenerative mouse model with tauopathy will be helpful for studying the underlying mechanism of pathological protein propagation as well as development of new therapies., (Copyright © 2019 IBRO. Published by Elsevier Ltd. All rights reserved.)

The dynamics of CNS function rely upon omnidirectional communication among CNS cell types. Extracellular vesicles (EVs) have emerged as key mediators of this communication and are actively involved in response to CNS injury, mediating inflammatory response and inflammation-related neuroprotection as they display dual beneficial and detrimental roles. Neuroimmune interactions include communication between neurons and microglia, the resident macrophages within the CNS, and these interactions are a critical mediator of healthy brain functions, mounting an inflammatory response, and disease pathogenesis. This review aims to organize recent research highlighting the role of EVs in health and neurodegenerative disorders, with a specific focus on neuroimmune interactions between neurons and glia in Alzheimer's disease., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Introduction: To report the five year results of a prospective, multi-center, randomized, blinded sham control trial of the Prostatic Urethral Lift (PUL) in men with bothersome lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH)., Materials and Methods: At 19 centers in North America and Australia, 206 subjects ≥ 50 years old with International Prostate Symptom Score (IPSS ) > 12, peak flow rate (Qmax) ≤ 12 mL/s, and prostate volume 30 cc-80 cc were randomized 2:1 to the PUL procedure or blinded sham control. In PUL permanent UroLift implants are placed to hold open the lateral lobes of the prostate to reduce urinary obstruction. After randomized comparison at 3 months and the only opportunity to add more PUL implants, PUL patients were followed to 5 years. LUTS severity (IPSS), quality of life (QOL), BPH Impact Index (BPHII), Qmax, sexual function, and adverse events were assessed throughout follow up., Results: IPSS improvement after PUL was 88% greater than that of sham at 3 months. LUTS and QOL were significantly improved by 2 weeks with return to preoperative physical activity within 8.6 days. Improvement in IPSS, QOL, BPHII, and Qmax were durable through 5 years with improvements of 36%, 50%, 52%, and 44% respectively. No difference was seen between Intent to Treat and Per Protocol populations. Surgical retreatment was 13.6% over 5 years. Adverse events were mild to moderate and transient. Sexual function was stable over 5 years with no de novo, sustained erectile or ejaculatory dysfunction., Conclusions: PUL offers rapid improvement in symptoms, QOL and flow rate that is durable to 5 years. These improvements were achieved with minimal use of a postoperative urinary catheter, rapid return to normal, and preservation of both erectile and ejaculatory function. Symptom improvement was commensurate with patient satisfaction. PUL offers a minimally invasive option in the treatment of LUTS due to BPH.

Background: Visual deficits following stroke are frequently subtle and are often overlooked. Even though these visual deficits may be less overt in nature, they are still debilitating to survivors. Visual deficits have been shown to negatively impact cognition, mobility, and activities of daily living (ADL). There is little consistency across healthcare facilities regarding protocol for assessing vision following stroke., Objective: This research was designed to describe a profile for patients exhibiting visual deficits following stroke, examine the role of occupational therapists in vision assessment, and discuss a potential model to provide a protocol for collaboration with an eye care professional as part of the rehabilitation team., Methods: The sample consisted of 131 patients in an inpatient rehabilitation (IPR) unit who were identified as having potential visual deficits. Occupational therapists on an IPR unit administered initial vision screenings and these patients were subsequently evaluated by the consulting optometrist. Frequencies were calculated for the appearance of functional symptoms, diagnoses, and recommendations. Correlations were also computed relating diagnoses and recommendations made., Results: All patients referred by the occupational therapist for optometrist evaluation had at least one visual diagnosis. The most frequent visual diagnoses included: saccades (77.7%), pursuits (61.8%), and convergence (63.4%). There was also a positive correlation between number of functional symptoms seen by occupational therapists and visual diagnoses made by the optometrist (r  =  0.209, P  =  0.016)., Conclusion: Results of this study support the need for vision assessment following stroke in IPR, confirm the role of occupational therapists in vision assessment, and support the need for an optometrist as a member of the rehabilitation team.