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1.
J Phys Chem A ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985992

ABSTRACT

We introduce a new method to remove the one-electron self-interaction error in approximate density functional calculations on an orbital-by-orbital basis, as originally proposed by Perdew and Zunger [Phys. Rev. B 1981, 23, 5048]. This method is motivated by a recent proposal by Pederson et al. [J. Chem. Phys. 2014, 140, 121103] to remove self-interaction that employs orbitals derived from the real-space density matrix, known as FLOSIC (Fermi Löwdin orbitals self-interaction correction). However, instead of Fermi Löwdin orbitals, our scheme utilizes columns of the density matrix to determine localized orbitals, like the localization procedure proposed by Fuemmeler et al. [J. Chem. Theory Comput. 2023, 19, 8572]. The new method, dubbed DOCSIC for density matrix as orbital coefficients self-interaction correction, contrasts with traditional Perdew-Zunger or FLOSIC in that it does not incorporate additional optimization parameters, and, unlike the average density self-interaction correction of Ciofini et al. [Chem. Phys. Lett. 2003, 380, 12], it makes use of localized orbitals. Another advantage of DOCSIC is that it can be implemented as a mean-field formalism. We show details of the self-consistent generalized Kohn-Sham implementation, some illustrative results, and we finally highlight its advantages and limitations.

2.
Nat Med ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965435

ABSTRACT

Differential diagnosis of dementia remains a challenge in neurology due to symptom overlap across etiologies, yet it is crucial for formulating early, personalized management strategies. Here, we present an artificial intelligence (AI) model that harnesses a broad array of data, including demographics, individual and family medical history, medication use, neuropsychological assessments, functional evaluations and multimodal neuroimaging, to identify the etiologies contributing to dementia in individuals. The study, drawing on 51,269 participants across 9 independent, geographically diverse datasets, facilitated the identification of 10 distinct dementia etiologies. It aligns diagnoses with similar management strategies, ensuring robust predictions even with incomplete data. Our model achieved a microaveraged area under the receiver operating characteristic curve (AUROC) of 0.94 in classifying individuals with normal cognition, mild cognitive impairment and dementia. Also, the microaveraged AUROC was 0.96 in differentiating the dementia etiologies. Our model demonstrated proficiency in addressing mixed dementia cases, with a mean AUROC of 0.78 for two co-occurring pathologies. In a randomly selected subset of 100 cases, the AUROC of neurologist assessments augmented by our AI model exceeded neurologist-only evaluations by 26.25%. Furthermore, our model predictions aligned with biomarker evidence and its associations with different proteinopathies were substantiated through postmortem findings. Our framework has the potential to be integrated as a screening tool for dementia in clinical settings and drug trials. Further prospective studies are needed to confirm its ability to improve patient care.

4.
Interdiscip Sci ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38954232

ABSTRACT

The electrical activity of the neural processes involved in cognitive functions is captured in EEG signals, allowing the exploration of the integration and coordination of neuronal oscillations across multiple spatiotemporal scales. We have proposed a novel approach that combines the transformation of EEG signal into image sequences, considering cross-frequency phase synchronisation (CFS) dynamics involved in low-level auditory processing, with the development of a two-stage deep learning model for the detection of developmental dyslexia (DD). This deep learning model exploits spatial and temporal information preserved in the image sequences to find discriminative patterns of phase synchronisation over time achieving a balanced accuracy of up to 83%. This result supports the existence of differential brain synchronisation dynamics between typical and dyslexic seven-year-old readers. Furthermore, we have obtained interpretable representations using a novel feature mask to link the most relevant regions during classification with the cognitive processes attributed to normal reading and those corresponding to compensatory mechanisms found in dyslexia.

5.
Theriogenology ; 226: 328-334, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38959843

ABSTRACT

The objective of this study was to compare the plasma (PL) and seminal plasma (SP) pharmacokinetic profile of ceftiofur (CEFT) and desuroylceftiofur acetamide (DFCA) after administration of CEFT crystalline-free acid (CCFA) by SC route in two sites of the ear in beef bulls. Four clinically healthy Hereford bulls received a comprehensive physical exam and subsequently a breeding-soundness examination, CBC, and chemistry profile panel. All bulls were diagnosed healthy and satisfactory potential breeders. In one group (n = 2), a single dose of CCFA was administered SC route at the base of the ear (BOE) at a dose of 6.6 mg/kg of body weight. The second group (n = 2) was also administered by SC route in the middle third of the posterior aspect of the ear (MTE). The concentrations of CEFT and DFCA in PL and SP were determined by a high-performance liquid chromatography mass spectrometry (HPLC-MS). Blood and semen samples were collected before the administration of CCFA and at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h after injection. No levels of CEFT were detected in PL and only in 20 of the 40 SP samples (P = 0.0001). The mean level of CEFT in SP was 0.11 % in comparison with the DFCA level. DFCA was found in all PL and SP samples. Therefore, DFCA was chosen to be utilized in the study of the pharmacokinetics parameters both in PL and SP. There were no differences in the mean PL levels of DFCA for the two sites of SC administration between the BOE (102.9 ± 78.9 ng/mL; X ± SD) and to MTE (116.1 ± 70.2 ng/mL; P = 0.58). The mean SP levels of DFCA after administration in the BOE was 857 ± 747 ng/mL, and for the MTE was 549 ± 488 ng/mL without differences between both sites (P = 0.15). The mean level of DFCA in PL was 109.5 ± 74.0 ng/mL, which was lower than the mean SP levels of 695 ± 103 ng/mL (P = 0.001). Moreover, the PL peak DFCA concentration (Cmax) was 229 ± 46 ng/mL at 36.0 ± 29.4 h (Tmax) post-administration. The SP Cmax was 1851 ± 533 ng/mL at 30.0 ± 28.6 h (Tmax) post-administration. The Cmax between PL and SP were distinctive (P = 0.004) without any differences in Tmax between PL and SP (P = 0.60). The terminal half-life for PL DFCA (47.4 ± 29.3 h) was not different than in SP (53.1 ± 23.6 h; P = 0.77). The PL area under the curve concentration time from the first to the last sample (AUC0-last) was 18,984 ± 4841 ng/mL/h, which was significatively smaller compared with 125,677 ± 59,445 ng/mL/h for SP AUC0-last (P = 0.04). The PL mean residence time from the first to the last sample (MRT0-last) was 69.7 ± 15.1 h, and it was similar than for SP of 66.5 ± 7.7 h (P = 0.69). From the present investigation, based in its pharmacokinetic features, it was concluded that CCFA should be an appropriate antibiotic that could be used for the treatment of bull genital infections when its indication is properly outlined. To study the pharmacokinetics of CCFA in SP, DFCA metabolite was appropriated.

6.
J Nematol ; 56(1): 20240023, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38975564

ABSTRACT

Recombinase polymerase amplification (RPA) is an isothermal in vitro nucleic acid amplification technique that has been adopted for simple, robust, rapid, reliable diagnostics of nematodes. In this study, the real-time RPA assay and RPA assay combined with lateral flow dipsticks (LF-RPA) have been developed targeting the ITS rRNA gene of the British root-knot nematode, Meloidogyne artiellia. The assay provided specific and rapid detection of this root-knot nematode species from crude nematode extracts without a DNA extraction step with a sensitivity of 0.125 second-stage juvenile (J2) specimen per a reaction tube for real-time RPA during 11 min and a sensitivity of 0.5 J2 specimens per a reaction tube for LF-RPA during 25 min. The RPA assays were validated with a wide range of non-target root-knot nematodes. The LF-RPA assay has great potential for nematode diagnostics in the laboratory having minimal available equipment.

7.
PLoS One ; 19(6): e0303252, 2024.
Article in English | MEDLINE | ID: mdl-38905275

ABSTRACT

Multifractality is a concept that extends locally the usual ideas of fractality in a system. Nevertheless, the multifractal approaches used lack a multifractal dimension tied to an entropy index like the Shannon index. This paper introduces a generalized Shannon index (GSI) and demonstrates its application in understanding system fluctuations. To this end, traditional multifractality approaches are explained. Then, using the temporal Theil scaling and the diffusive trajectory algorithm, the GSI and its partition function are defined. Next, the multifractal exponent of the GSI is derived from the partition function, establishing a connection between the temporal Theil scaling exponent and the generalized Hurst exponent. Finally, this relationship is verified in a fractional Brownian motion and applied to financial time series. In fact, this leads us to proposing an approximation called local fractional Brownian motion approximation, where multifractal systems are viewed as a local superposition of distinct fractional Brownian motions with varying monofractal exponents. Also, we furnish an algorithm for identifying the optimal q-th moment of the probability distribution associated with an empirical time series to enhance the accuracy of generalized Hurst exponent estimation.


Subject(s)
Algorithms , Fractals , Entropy , Time Factors
8.
Lancet Gastroenterol Hepatol ; 9(8): 694-704, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38823398

ABSTRACT

BACKGROUND: In the preplanned interim analysis of the TOPAZ-1 study, durvalumab plus gemcitabine-cisplatin significantly improved overall survival versus placebo plus gemcitabine-cisplatin in participants with advanced biliary tract cancer. We aimed to report updated overall survival and safety data from TOPAZ-1 with additional follow-up and data maturity beyond the interim analysis. METHODS: TOPAZ-1 was a phase 3, randomised, double-masked, placebo-controlled, global study done at 105 sites in 17 countries. Participants aged 18 years or older with unresectable, locally advanced, or metastatic biliary tract cancer were randomly assigned (1:1) to durvalumab plus gemcitabine-cisplatin or placebo plus gemcitabine-cisplatin using a computer-generated randomisation scheme, stratified by disease status and primary tumour location. Participants received durvalumab (1500 mg) or placebo on day 1 of each cycle every 3 weeks for up to eight cycles, plus gemcitabine (1000 mg/m2) and cisplatin (25 mg/m2) intravenously on days 1 and 8 of each cycle every 3 weeks for up to eight cycles, followed by durvalumab (1500 mg) or placebo monotherapy every 4 weeks until disease progression or other discontinuation criteria were met. Investigators and participants were masked to study treatment. The primary endpoint was overall survival. TOPAZ-1 met its primary endpoint at the preplanned interim analysis, and the study is active but no longer recruiting participants. Updated overall survival and safety data from TOPAZ-1, with additional follow-up (data cutoff Feb 25, 2022) and data maturity beyond the interim analysis, are reported here. Efficacy was assessed in the full analysis set (all randomly assigned participants). Safety was assessed in the safety analysis set (all participants who received at least one dose of study treatment). The TOPAZ-1 study is registered with ClinicalTrials.gov, NCT03875235. FINDINGS: From April 16, 2019, to Dec 11, 2020, 914 participants were enrolled, 685 of whom were randomly assigned (341 to the durvalumab plus gemcitabine-cisplatin group and 344 to the placebo plus gemcitabine-cisplatin group). 345 (50%) participants were male and 340 (50%) were female. Median follow-up at the updated data cutoff was 23·4 months (95% CI 20·6-25·2) in the durvalumab plus gemcitabine-cisplatin group and 22·4 months (21·4-23·8) in the placebo plus gemcitabine-cisplatin group. At the updated data cutoff, 248 (73%) participants in the durvalumab plus gemcitabine-cisplatin group and 279 (81%) participants in the placebo plus gemcitabine-cisplatin group had died (median overall survival 12·9 months [95% CI 11·6-14·1] vs 11·3 months [10·1-12·5]; hazard ratio 0·76 [95% CI 0·64-0·91]). Kaplan-Meier-estimated 24-month overall survival rates were 23·6% (95% CI 18·7-28·9) in the durvalumab plus gemcitabine-cisplatin group and 11·5% (7·6-16·2) in the placebo plus gemcitabine-cisplatin group. Maximum grade 3 or 4 adverse events occurred in 250 (74%) of 338 participants in the durvalumab plus gemcitabine-cisplatin group and 257 (75%) of 342 in the placebo plus gemcitabine-cisplatin group. The most common maximum grade 3 or 4 treatment-related adverse events were decreased neutrophil count (70 [21%] vs 86 [25%]), anaemia (64 [19%] vs 64 [19%]), and neutropenia (63 [19%] vs 68 [20%]). INTERPRETATION: Durvalumab plus gemcitabine-cisplatin showed robust and sustained overall survival benefit with no new safety signals. Findings continue to support the regimen as a standard of care for people with untreated, advanced biliary tract cancer. FUNDING: AstraZeneca.


Subject(s)
Antibodies, Monoclonal , Antineoplastic Combined Chemotherapy Protocols , Biliary Tract Neoplasms , Cisplatin , Deoxycytidine , Gemcitabine , Humans , Cisplatin/administration & dosage , Cisplatin/therapeutic use , Deoxycytidine/analogs & derivatives , Deoxycytidine/administration & dosage , Deoxycytidine/therapeutic use , Biliary Tract Neoplasms/drug therapy , Biliary Tract Neoplasms/mortality , Biliary Tract Neoplasms/pathology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Male , Female , Middle Aged , Double-Blind Method , Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal/adverse effects , Adult , Survival Rate
9.
bioRxiv ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38895239

ABSTRACT

Post-Acute Sequelae of COVID-19 (PASC) encompasses persistent neurological symptoms, including olfactory and autonomic dysfunction. Here, we report chronic neurological dysfunction in mice infected with a virulent mouse-adapted SARS-CoV-2 that does not infect the brain. Long after recovery from nasal infection, we observed loss of tyrosine hydroxylase (TH) expression in olfactory bulb glomeruli and neurotransmitter levels in the substantia nigra (SN) persisted. Vulnerability of dopaminergic neurons in these brain areas was accompanied by increased levels of proinflammatory cytokines and neurobehavioral changes. RNAseq analysis unveiled persistent microglia activation, as found in human neurodegenerative diseases. Early treatment with antivirals (nirmatrelvir and molnupiravir) reduced virus titers and lung inflammation but failed to prevent neurological abnormalities, as observed in patients. Together these results show that chronic deficiencies in neuronal function in SARS-CoV-2-infected mice are not directly linked to ongoing olfactory epithelium dysfunction. Rather, they bear similarity with neurodegenerative disease, the vulnerability of which is exacerbated by chronic inflammation.

10.
EBioMedicine ; 105: 105216, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38924841

ABSTRACT

BACKGROUND: This study aimed to characterise the infant penile (coronal sulcus) microbiome and the effects of early infant male circumcision (EIMC), following a standard surgical method (Mogen Clamp) and a non-surgical alternative (ShangRing). METHODS: We collected coronal sulcus swabs at baseline and on days 7 and 14 post-circumcision from infants assigned to receive EIMC by Mogen Clamp (n = 15) or ShangRing (n = 15), in a randomised trial in Rakai and Kakuuto, Uganda. We used 16S rRNA gene-based sequencing and broad-coverage qPCR to characterise the infant penile microbiome and assess the effects of EIMC in both study arms. FINDINGS: Prior to EIMC, the infant penile microbiome had a mixture of facultative and strict anaerobes. In both study arms, EIMC caused penile microbiome proportional abundance changes characterised by decreases in penile anaerobes [ShangRing Prevotella: -15.0%, (SD = 19.1); Mogen clamp Prevotella: -3.6% (11.2); ShangRing Veillonella: -11.3% (17.2); Mogen clamp Veillonella: -2.6% (11.8)] and increases in skin-associated facultative anaerobes [ShangRing Corynebacterium: 24.9%, (22.4); Mogen clamp Corynebacterium: 4.7% (21.3); ShangRing Staphylococcus: 21.1% (20.5); Mogen clamp Staphylococcus: 18.1% (20.1)]. Clostridium tetani was not detected during the study. INTERPRETATION: Mogen Clamp and ShangRing EIMC both changed the composition of the infant penile microbiome by reducing the proportional abundances of anaerobes and uropathogens, which is consistent with medical male circumcision findings in adults. C. tetani was not increased by either EIMC method. FUNDING: Bill and Melinda Gates Foundation.

11.
Elife ; 122024 Jun 19.
Article in English | MEDLINE | ID: mdl-38896568

ABSTRACT

We present open-source tools for three-dimensional (3D) analysis of photographs of dissected slices of human brains, which are routinely acquired in brain banks but seldom used for quantitative analysis. Our tools can: (1) 3D reconstruct a volume from the photographs and, optionally, a surface scan; and (2) produce a high-resolution 3D segmentation into 11 brain regions per hemisphere (22 in total), independently of the slice thickness. Our tools can be used as a substitute for ex vivo magnetic resonance imaging (MRI), which requires access to an MRI scanner, ex vivo scanning expertise, and considerable financial resources. We tested our tools on synthetic and real data from two NIH Alzheimer's Disease Research Centers. The results show that our methodology yields accurate 3D reconstructions, segmentations, and volumetric measurements that are highly correlated to those from MRI. Our method also detects expected differences between post mortem confirmed Alzheimer's disease cases and controls. The tools are available in our widespread neuroimaging suite 'FreeSurfer' (https://surfer.nmr.mgh.harvard.edu/fswiki/PhotoTools).


Every year, thousands of human brains are donated to science. These brains are used to study normal aging, as well as neurological diseases like Alzheimer's or Parkinson's. Donated brains usually go to 'brain banks', institutions where the brains are dissected to extract tissues relevant to different diseases. During this process, it is routine to take photographs of brain slices for archiving purposes. Often, studies of dead brains rely on qualitative observations, such as 'the hippocampus displays some atrophy', rather than concrete 'numerical' measurements. This is because the gold standard to take three-dimensional measurements of the brain is magnetic resonance imaging (MRI), which is an expensive technique that requires high expertise ­ especially with dead brains. The lack of quantitative data means it is not always straightforward to study certain conditions. To bridge this gap, Gazula et al. have developed an openly available software that can build three-dimensional reconstructions of dead brains based on photographs of brain slices. The software can also use machine learning methods to automatically extract different brain regions from the three-dimensional reconstructions and measure their size. These data can be used to take precise quantitative measurements that can be used to better describe how different conditions lead to changes in the brain, such as atrophy (reduced volume of one or more brain regions). The researchers assessed the accuracy of the method in two ways. First, they digitally sliced MRI-scanned brains and used the software to compute the sizes of different structures based on these synthetic data, comparing the results to the known sizes. Second, they used brains for which both MRI data and dissection photographs existed and compared the measurements taken by the software to the measurements obtained with MRI images. Gazula et al. show that, as long as the photographs satisfy some basic conditions, they can provide good estimates of the sizes of many brain structures. The tools developed by Gazula et al. are publicly available as part of FreeSurfer, a widespread neuroimaging software that can be used by any researcher working at a brain bank. This will allow brain banks to obtain accurate measurements of dead brains, allowing them to cheaply perform quantitative studies of brain structures, which could lead to new findings relating to neurodegenerative diseases.


Subject(s)
Alzheimer Disease , Brain , Imaging, Three-Dimensional , Machine Learning , Humans , Imaging, Three-Dimensional/methods , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/pathology , Brain/diagnostic imaging , Brain/pathology , Photography/methods , Dissection , Magnetic Resonance Imaging/methods , Neuropathology/methods , Neuroimaging/methods
12.
mBio ; : e0072624, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847540

ABSTRACT

The modulation of actin polymerization is a common theme among microbial pathogens. Even though microorganisms show a wide repertoire of strategies to subvert the activity of actin, most of them converge in the ones that activate nucleating factors, such as the Arp2/3 complex. Brucella spp. are intracellular pathogens capable of establishing chronic infections in their hosts. The ability to subvert the host cell response is dependent on the capacity of the bacterium to attach, invade, avoid degradation in the phagocytic compartment, replicate in an endoplasmic reticulum-derived compartment and egress. Even though a significant number of mechanisms deployed by Brucella in these different phases have been identified and characterized, none of them have been described to target actin as a cellular component. In this manuscript, we describe the identification of a novel virulence factor (NpeA) that promotes niche formation. NpeA harbors a short linear motif (SLiM) present within an amphipathic alpha helix that has been described to bind the GTPase-binding domain (GBD) of N-WASP and stabilizes the autoinhibited state. Our results show that NpeA is secreted in a Type IV secretion system-dependent manner and that deletion of the gene diminishes the intracellular replication capacity of the bacterium. In vitro and ex vivo experiments demonstrate that NpeA binds N-WASP and that the short linear motif is required for the biological activity of the protein.IMPORTANCEThe modulation of actin-binding effectors that regulate the activity of this fundamental cellular protein is a common theme among bacterial pathogens. The neural Wiskott-Aldrich syndrome protein (N-WASP) is a protein that several pathogens target to hijack actin dynamics. The highly adapted intracellular bacterium Brucella has evolved a wide repertoire of virulence factors that modulate many activities of the host cell to establish successful intracellular replication niches, but, to date, no effector proteins have been implicated in the modulation of actin dynamics. We present here the identification of a virulence factor that harbors a short linear motif (SLiM) present within an amphipathic alpha helix that has been described to bind the GTPase-binding domain (GBD) of N-WASP stabilizing its autoinhibited state. We demonstrate that this protein is a Type IV secretion effector that targets N-WASP-promoting intracellular survival and niche formation.

13.
J Affect Disord ; 360: 297-304, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823589

ABSTRACT

BACKGROUND AND AIM: The association between the Triglyceride-glucose (TyG) index and depression has been observed, yet its confirmation within peri- and postmenopausal demographics remains elusive. Consequently, the principal aim of this investigation is to explore the nexus between TyG-related indicators and depressive symptoms among pre- and postmenopausal women. METHODS: The data utilized in this study were obtained from the National Health and Nutrition Examination Survey (NHANES) conducted from 2013 to 2016. The patients were divided into three groups based on TyG, Triglyceride-Glucose-Body Mass Index (TyG-BMI), Triglyceride-Glucose-Waist Circumference (TyG-WC), and Triglyceride-Glucose-Waist-to-Height Ratio (TyG-WHtR): Q1 (1st quintile), Q2 (2nd quintile), and Q3 (3rd quintile). Further exploration of the differences between these groups was conducted. Employing logistic regression, stratified analysis, restricted cubic splines, and subgroup analyses, we scrutinized the correlation between TyG-related indicators and depressive symptoms in both premenopausal and postmenopausal women. Furthermore, sensitivity analyses were conducted to assess the durability and uniformity of this relationship. RESULTS: In premenopausal women, there was a consistent independent positive correlation between TyG-BMI, TyG-WC, and TyG-WHtR with depressive symptoms across all three models, while TyG itself did not show a significant association. In Models 1 and 2, TyG-BMI exhibited a higher odds ratio (OR) value than the other two indicators [Model 1, Q3 OR (95 % confidence interval, CI) = 3.37 (1.91-5.94); Model 2, Q3 OR (95 % CI) = 3.03 (1.67-5.52)]. In Models 3, TyG-WHtR demonstrates a more significant association with depressive symptoms [Model 3, Q3 OR (95 % CI) = 2.85 (1.55-5.27)]. This correlation does not manifest in menopausal women. CONCLUSIONS: In premenopausal women, TyG-BMI, TyG-WC, and TyG-WHtR exhibited a positive and linear relationship with depressive symptoms. Furthermore, the analysis revealed that the combined measures of TyG-BMI, TyG-WC, and TyG-WHtR offered greater precision and sensitivity in assessing this association compared to TyG alone.


Subject(s)
Blood Glucose , Body Mass Index , Depression , Nutrition Surveys , Postmenopause , Premenopause , Triglycerides , Humans , Female , Postmenopause/blood , Postmenopause/psychology , Triglycerides/blood , Premenopause/blood , Premenopause/psychology , Middle Aged , Adult , Depression/blood , Depression/epidemiology , Blood Glucose/analysis , Waist Circumference , Cross-Sectional Studies , Aged
14.
Biol Res ; 57(1): 39, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38867288

ABSTRACT

BACKGROUND: Spreading depression (SD) is an intriguing phenomenon characterized by massive slow brain depolarizations that affect neurons and glial cells. This phenomenon is repetitive and produces a metabolic overload that increases secondary damage. However, the mechanisms associated with the initiation and propagation of SD are unknown. Multiple lines of evidence indicate that persistent and uncontrolled opening of hemichannels could participate in the pathogenesis and progression of several neurological disorders including acute brain injuries. Here, we explored the contribution of astroglial hemichannels composed of connexin-43 (Cx43) or pannexin-1 (Panx1) to SD evoked by high-K+ stimulation in brain slices. RESULTS: Focal high-K+ stimulation rapidly evoked a wave of SD linked to increased activity of the Cx43 and Panx1 hemichannels in the brain cortex, as measured by light transmittance and dye uptake analysis, respectively. The activation of these channels occurs mainly in astrocytes but also in neurons. More importantly, the inhibition of both the Cx43 and Panx1 hemichannels completely prevented high K+-induced SD in the brain cortex. Electrophysiological recordings also revealed that Cx43 and Panx1 hemichannels critically contribute to the SD-induced decrease in synaptic transmission in the brain cortex and hippocampus. CONCLUSIONS: Targeting Cx43 and Panx1 hemichannels could serve as a new therapeutic strategy to prevent the initiation and propagation of SD in several acute brain injuries.


Subject(s)
Astrocytes , Connexin 43 , Connexins , Cortical Spreading Depression , Synaptic Transmission , Animals , Astrocytes/physiology , Connexins/metabolism , Cortical Spreading Depression/physiology , Cortical Spreading Depression/drug effects , Synaptic Transmission/physiology , Synaptic Transmission/drug effects , Connexin 43/metabolism , Male , Nerve Tissue Proteins/metabolism , Cerebral Cortex , Neurons/physiology , Hippocampus , Rats, Sprague-Dawley , Rats , Potassium/metabolism
15.
Eur Respir J ; 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38871375

ABSTRACT

BACKGROUND: Primary ciliary dyskinesia (PCD) represents a group of rare hereditary disorders characterized by deficient ciliary airway clearance that can be associated with laterality defects. We aimed to describe the underlying gene defects, geographical differences in genotypes and their relationship to diagnostic findings and clinical phenotypes. METHODS: Genetic variants and clinical findings (age, sex, body mass index, laterality defects, FEV1) were collected from 19 countries using the ERN LUNG International PCD Registry. Genetic data were evaluated according to ACMG guidelines. We assessed regional distribution of implicated genes and genetic variants as well as genotype correlations with laterality defects and FEV1. RESULTS: 1236 individuals carried 908 distinct pathogenic DNA variants in 46 PCD genes. We found considerable variation in the distribution of PCD genotypes across countries due to the presence of distinct founder variants. The prevalence of PCD genotypes associated with pathognomonic ultrastructural defects (mean 72%; 47-100%) and laterality defects (mean 42%; 28-69%) varied widely among the countries. The prevalence of laterality defects was significantly lower in PCD individuals without pathognomonic ciliary ultrastructure defects (18%). The PCD cohort had a reduced median FEV1 z-score (-1.66). In the group of individuals with CCNO (-3.26), CCDC39 (-2.49), and CCDC40 (-2.96) variants, FEV1 z-scores were significantly lower, while the group of DNAH11 (-0.83) and ODAD1 (-0.85) variant individuals had significantly milder FEV1 z-score reductions compared to the whole PCD cohort. CONCLUSION: This unprecedented multinational dataset of DNA variants and information on their distribution across countries facilitates interpretation of genetic epidemiology of PCD and provides prediction of diagnostic and phenotypic features such as the course of lung function.

17.
Stem Cells Transl Med ; 13(7): 678-692, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38761090

ABSTRACT

Cardiomyocyte (CM) proliferation and maturation are highly linked processes, however, the extent to which these processes are controlled by a single signaling axis is unclear. Here, we show the previously undescribed role of Hedgehog (HH)-GLI2-CKS1B cascade in regulation of the toggle between CM proliferation and maturation. Here we show downregulation of GLI-signaling in adult human CM, adult murine CM, and in late-stage hiPSC-CM leading to their maturation. In early-stage hiPSC-CM, inhibition of HH- or GLI-proteins enhanced CM maturation with increased maturation indices, increased calcium handling, and transcriptome. Mechanistically, we identified CKS1B, as a new effector of GLI2 in CMs. GLI2 binds the CKS1B promoter to regulate its expression. CKS1B overexpression in late-stage hiPSC-CMs led to increased proliferation with loss of maturation in CMs. Next, analysis of datasets of patients with heart disease showed a significant enrichment of GLI2-signaling in patients with ischemic heart failure (HF) or dilated-cardiomyopathy (DCM) disease, indicating operational GLI2-signaling in the stressed heart. Thus, the Hh-GLI2-CKS1B axis regulates the proliferation-maturation transition and provides targets to enhance cardiac tissue engineering and regenerative therapies.


Subject(s)
Cell Proliferation , Myocytes, Cardiac , Zinc Finger Protein Gli2 , Myocytes, Cardiac/metabolism , Humans , Zinc Finger Protein Gli2/metabolism , Zinc Finger Protein Gli2/genetics , Animals , Mice , Hedgehog Proteins/metabolism , Signal Transduction , Induced Pluripotent Stem Cells/metabolism , Cell Differentiation
18.
Adv Emerg Nurs J ; 46(2): 126-140, 2024.
Article in English | MEDLINE | ID: mdl-38736097

ABSTRACT

Ensuring correct placement of the endotracheal tube (ETT) during intubation is an important step to avoid complications. Appropriate placement of the ETT can be challenging and, if done incorrectly, can lead to complications such as hypoxemia, atelectasis, hyperinflation, barotrauma, cardiovascular instability, end organ damage, and even death. Although several procedures exist to help assess ETT confirmation, all have limitations, are not always reliable, and vary in their degree of accuracy. Point-of-care ultrasound (POCUS) has emerged as a useful tool in the emergency department for quick diagnosis and treatment of many emergency conditions (Gonzalez et al., 2020). The purpose of this paper is to describe a systematic approach for the emergency nurse practitioner to use POCUS to assess proper endotracheal placement and the positioning within the trachea based on prior studies that compare this modality to traditional ones.


Subject(s)
Intubation, Intratracheal , Nurse Practitioners , Point-of-Care Systems , Ultrasonography , Humans , Intubation, Intratracheal/nursing , Intubation, Intratracheal/methods , Emergency Service, Hospital , Emergency Nursing
19.
J Neuroinflammation ; 21(1): 144, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38822334

ABSTRACT

Cumulative evidence has established that Interferon (IFN)-γ has both pathogenic and protective roles in Multiple Sclerosis and the animal model, Experimental Autoimmune Encephalomyelitis (EAE). However, the underlying mechanisms to the beneficial effects of IFN-γ are not well understood. In this study, we found that IFN-γ exerts therapeutic effects on chronic, relapsing-remitting, and chronic progressive EAE models. The frequency of regulatory T (Treg) cells in spinal cords from chronic EAE mice treated with IFN-γ was significantly increased with no effect on Th1 and Th17 cells. Consistently, depletion of FOXP3-expressing cells blocked the protective effects of IFN-γ, indicating that the therapeutic effect of IFN-γ depends on the presence of Treg cells. However, IFN-γ did not trigger direct in vitro differentiation of Treg cells. In vivo administration of blocking antibodies against either interleukin (IL)-10, transforming growth factor (TGF)-ß or program death (PD)-1, revealed that the protective effects of IFN-γ in EAE were also dependent on TGF-ß and PD-1, but not on IL-10, suggesting that IFN-γ might have an indirect role on Treg cells acting through antigen-presenting cells. Indeed, IFN-γ treatment increased the frequency of a subset of splenic CD11b+ myeloid cells expressing TGF-ß-Latency Associated Peptide (LAP) and program death ligand 1 (PD-L1) in a signal transducer and activator of transcription (STAT)-1-dependent manner. Furthermore, splenic CD11b+ cells from EAE mice preconditioned in vitro with IFN-γ and myelin oligodendrocyte glycoprotein (MOG) peptide exhibited a tolerogenic phenotype with the capability to induce conversion of naïve CD4+ T cells mediated by secretion of TGF-ß. Remarkably, adoptive transfer of splenic CD11b+ cells from IFN-γ-treated EAE mice into untreated recipient mice ameliorated clinical symptoms of EAE and limited central nervous system infiltration of mononuclear cells and effector helper T cells. These results reveal a novel cellular and molecular mechanism whereby IFN-γ promotes beneficial effects in EAE by endowing splenic CD11b+ myeloid cells with tolerogenic and therapeutic activities.


Subject(s)
CD11b Antigen , Encephalomyelitis, Autoimmune, Experimental , Interferon-gamma , Mice, Inbred C57BL , Myeloid Cells , Spleen , Animals , Encephalomyelitis, Autoimmune, Experimental/immunology , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Mice , Interferon-gamma/metabolism , Myeloid Cells/drug effects , Myeloid Cells/immunology , Myeloid Cells/metabolism , Spleen/immunology , CD11b Antigen/metabolism , Female , Myelin-Oligodendrocyte Glycoprotein/toxicity , Myelin-Oligodendrocyte Glycoprotein/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/drug effects , Peptide Fragments/toxicity , Peptide Fragments/pharmacology , Transforming Growth Factor beta/metabolism , Programmed Cell Death 1 Receptor/metabolism , Programmed Cell Death 1 Receptor/immunology , Forkhead Transcription Factors/metabolism , Disease Models, Animal
20.
Microbiol Res ; 285: 127739, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38763016

ABSTRACT

Clostridioides difficile may have a negative impact on gut microbiota composition in terms of diversity and abundance, thereby triggering functional changes supported by the differential presence of genes involved in significant metabolic pathways, such as short-chain fatty acids (SCFA). This work has evaluated shotgun metagenomics data regarding 48 samples from four groups classified according to diarrhea acquisition site (community- and healthcare facility-onset) and positive or negative Clostridioides difficile infection (CDI) result. The metagenomic-assembled genomes (MAGs) obtained from each sample were taxonomically assigned for preliminary comparative analysis concerning differences in composition among groups. The predicted genes involved in metabolism, transport, and signaling remained constant in microbiota members; characteristic patterns were observed in MAGs and genes involved in SCFA butyrate and acetate metabolic pathways for each study group. A decrease in genera and species, as well as relative MAG abundance with the presence of the acetate metabolism-related gene, was evident in the HCFO/- group. Increased antibiotic resistance markers (ARM) were observed in MAGs along with the genes involved in acetate metabolism. The results highlight the need to explore the role of acetate in greater depth as a potential protector of the imbalances produced by CDI, as occurs in other inflammatory intestinal diseases.


Subject(s)
Acetates , Clostridioides difficile , Clostridium Infections , Gastrointestinal Microbiome , Metagenome , Metagenomics , Clostridioides difficile/genetics , Acetates/metabolism , Humans , Clostridium Infections/microbiology , Fatty Acids, Volatile/metabolism , Genome, Bacterial , Butyrates/metabolism , Metabolic Networks and Pathways/genetics , Feces/microbiology , Diarrhea/microbiology
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