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1.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38258918

RESUMO

Photodetachment spectra of anionic species provide significant insights into the energies and nature of ground and excited states of both the anion and resultant neutral molecules. Direct detachment of the excess electron to the continuum may occur via formally allowed or forbidden transitions (perhaps as the result of intensity borrowing through vibronic coupling). However, alternate indirect pathways are also possible and often overlooked. Here, we report a two-dimensional photoelectron spectral study, combined with correlated electronic structure calculations, to elucidate the nature of photodetachment from NiO2-. The spectra are comprised of allowed and forbidden transitions, in excellent agreement with previously reported slow electron velocity mapped imaging spectra of the same system, which were interpreted in terms of direct detachment. In the current work, the contributions of indirect processes are revealed. Measured oscillations in the branching ratios of the spectral channels clearly indicate non-direct detachment processes, and the electronic structure calculations suggest that excited states of the appropriate symmetry and degeneracy lie slightly above the neutral ground state. Taken together, the results suggest that the origin of the observed forbidden transitions is the result of anion excited states mediating the electron detachment process.

2.
Glob Chang Biol ; 30(1): e16991, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37905464

RESUMO

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a "middle of the road" scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26-43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from -20 to -191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.


Assuntos
Tartarugas , Animais , Tartarugas/fisiologia , Temperatura , Mudança Climática , Reprodução , Razão de Masculinidade
4.
ESMO Open ; 8(6): 102033, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866031

RESUMO

BACKGROUND: Trastuzumab deruxtecan (T-DXd) has demonstrated efficacy in patients with brain metastasis (BM), a group historically with poor outcomes. The prevalence of BMs in patients commencing T-DXd is currently unknown. No direct comparisons have been made of the activity of T-DXd in patients with active BM versus those with extracranial progression alone. This real-world study explored the prevalence of BMs in patients commencing T-DXd, the efficacy of T-DXd in active BM versus extracranial progression alone and the safety of T-DXd. PATIENTS AND METHODS: Patients with human epidermal growth factor receptor 2-positive advanced breast cancer treated with T-DXd between June 2021 and February 2023 at our specialist cancer hospital were identified and notes reviewed. Clinicopathological information, prior treatment, the presence or absence of central nervous system (CNS) disease, outcomes and treatment-emergent adverse events (TEAEs) were recorded. RESULTS: Twenty-nine female patients, with a median age of 52 years (interquartile range 44-62 years), were identified; the prevalence of BM was 41%. Median number of lines of prior therapy was 2 (range 2-6). At a median follow-up of 13.8 months, median progression-free survival (PFS) for the overall population was 13.9 months [95% confidence interval (CI) 12.4 months-not estimable (NE)], 16.1 months (95% CI 15.1 months-NE) for active BMs and 12.4 months (95% CI 8.3 months-NE) for progressive extracranial disease alone. The 12-month overall survival (OS) rate was 74% (95% CI 59% to 95%) in the overall population, and 83% (95% CI 58% to 100%) and 66% (95% CI 45% to 96%) for active BMs and extracranial disease only, respectively. Most common TEAEs were fatigue, alopecia, and constipation. In nine patients (31%, including two deaths), pneumonitis occurred. CONCLUSION: In this real-world population, we demonstrate T-DXd to be effective in patients with active BMs and those with progressive extracranial disease alone. PFS and OS were numerically longer in those with active BMs. These data demonstrate that patients with active BM treated with T-DXd have at least comparable outcomes to those with extracranial disease alone. The high rate of pneumonitis warrants further consideration.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Pneumonia , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias da Mama/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Trastuzumab/efeitos adversos
5.
Health Equity ; 7(1): 333-337, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284533

RESUMO

The Department of Veterans Affairs (VA) initiative to enhance recruitment of diverse biomedical scientists from Historically Black Colleges and Universities (HBCUs) through the VA Career Development Program has provided a unique opportunity for HBCUs to partner with VA to strengthen diversity recruitment efforts. The Atlanta VA Health Care System and the Morehouse School of Medicine (MSM) enjoy a productive and growing interinstitutional collaboration. The partnership between the Atlanta VA and MSM provides the unique opportunity for MSM to increase research opportunities for faculty and students while providing a pipeline of diverse candidates for the Atlanta VA to enhance recruitment of diverse HCBU biomedical scientists. This relationship led to the creation of an inaugural HBCU Core Recruitment Site (CRS) at MSM and the Atlanta VA. The CRS provides a pathway to identify and recruit young diverse investigators who are eligible to compete for VA Career Development Award funding. This Atlanta VA/MSM CRS initiative established a pipeline program to further enhance diversity in the VA scientific workforce. In this review, the Atlanta VA/MSM CRS is presented as a potential model for maximizing the VA initiative to enhance the recruitment of diverse candidates from HBCUs.

6.
Appetite ; 180: 106348, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272545

RESUMO

Responsive feeding, where parents are guided by children's hunger and satiation cues and provide appropriate structure and support for eating, is believed to promote healthier weight status. However, few studies have assessed prospective associations between observed parental feeding and toddler growth. We characterized toddler growth from 18 to 36 months and, in a subset of families, examined whether observed maternal responsiveness to toddler satiation cues and encouraging prompts to eat at 18 and 24 months were associated with toddler body mass index z-score (BMIz) from 18 to 36 months. Participants included 163 toddlers and their mothers with overweight/obesity who had participated in a lifestyle intervention during pregnancy. Anthropometrics were measured at 18, 24, and 36 months. In a subsample, mealtime interactions were recorded in families' homes at 18 (n = 77) and 24 (n = 75) months. On average, toddler BMIz remained stable from 18 to 36 months with 31.3% (n = 51) categorized with a healthy weight, 56.4% (n = 92) with at risk for overweight and 12.3% (n = 20) with overweight. Fewer maternal prompts to eat at 18 months was associated with both higher probability of having at risk for overweight/overweight (p < .05), and higher child 36-month BMIz (p = .002). Higher child weight status at 12 months was also associated with both higher probability of having at risk for overweight/overweight (p < .05), and higher child 36-month BMIz (p < .001). Neither 24-month maternal prompts nor 18 or 24 month responsiveness to satiation cues were associated with toddler BMIz. In this diverse sample, weight status was relatively stable from 18 to 36 months. Maternal prompts to eat measured earlier in toddlerhood and prior child weight status were associated with toddler BMIz.


Assuntos
Nível de Saúde , Pais , Humanos , Feminino , Índice de Massa Corporal , Mães
7.
Alcohol ; 106: 30-43, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36328183

RESUMO

Alcohol use disorders (AUD) cause alveolar macrophage (AM) immune dysfunction and increase risk of lung infections. Excessive alcohol use causes AM oxidative stress, which impairs AM phagocytosis and pathogen clearance from the alveolar space. Alcohol induces expression of NADPH oxidases (Noxes), primary sources of oxidative stress in AM. In contrast, alcohol decreases AM peroxisome proliferator-activated receptor gamma (PPARγ), a critical regulator of AM immune function. To explore the underlying molecular mechanisms for these effects of alcohol, we hypothesized that ethanol promotes CCAAT/enhancer-binding protein beta (C/EBPß)-mediated suppression of Nox-related microRNAs (miRs), in turn enhancing AM Nox expression, oxidative stress, and phagocytic dysfunction. We also hypothesized that PPARγ activation with pioglitazone (PIO) would reverse alcohol-induced C/EBPß expression and attenuate AM oxidative stress and phagocytic dysfunction. Cells from the mouse AM cell line (MH-S) were exposed to ethanol in vitro or primary AM were isolated from mice fed ethanol in vivo. Ethanol enhanced C/EBPß expression, decreased Nox 1-related miR-1264 and Nox 2-related miR-107 levels, and increased Nox1, Nox2, and Nox 4 expression in MH-S cells in vitro and mouse AM in vivo. These alcohol-induced AM derangements were abrogated by loss of C/EBPß, overexpression of miRs-1264 or -107, or PIO treatment. These findings identify C/EBPß and Nox-related miRs as novel therapeutic targets for PPARγ ligands, which could provide a translatable strategy to mitigate susceptibility to lung infections in people with a history of AUD. These studies further clarify the molecular underpinnings for a previous clinical trial using short-term PIO treatment to improve AM immunity in AUD individuals.


Assuntos
Etanol , Macrófagos Alveolares , MicroRNAs , Processamento Pós-Transcricional do RNA , Animais , Camundongos , Alcoolismo/tratamento farmacológico , Alcoolismo/genética , Etanol/efeitos adversos , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , PPAR gama/genética , PPAR gama/metabolismo
8.
Sci Rep ; 12(1): 22076, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543902

RESUMO

Enteric neuron degeneration has been observed during aging, and in individuals with metabolic dysfunction including obesity and diabetes. Honokiol, a naturally occurring compound, is an activator of Sirtuin-3 (SIRT3) that has antioxidant activity. Its role in modulating enteric neuron-specific neurodegeneration is unknown. We studied the effects of honokiol and its fluorinated analog, hexafluoro-honokiol, on enteric neuronal differentiation and survival. We used a previously established model of mouse primary enteric neuronal cells and an enteric neuronal cell line treated with palmitate (PA) and lipopolysaccharide (LPS) to induce mitochondrial dysfunction and enteric neuronal cell death. The effect of honokiol and hexafluoro-honokiol was assessed on neuronal phenotype, fiber density, differentiation, and pyroptosis. Honokiol and hexafluoro-honokiol significantly increased neuronal networks and fiber density in enteric neurons and increased levels of neuronal nitric oxide synthase and Choline acetyltransferase mRNA. Hexafluoro-honokiol and honokiol also significantly increased SIRT3 mRNA levels and suppressed palmitate and LPS-induced neuronal pyroptosis. SIRT3 knock-down prevented the hexafluoro-honokiol mediated suppression of mitochondrial superoxide release. Our data supports a neuroprotective effect of honokiol and its derivative and these could be used as prophylactic or therapeutic agents for treating enteric neurodegeneration and associated motility disorders.


Assuntos
Sistema Nervoso Entérico , Sirtuína 3 , Animais , Camundongos , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Diferenciação Celular/genética , Sistema Nervoso Entérico/efeitos dos fármacos , Sistema Nervoso Entérico/metabolismo , Lipopolissacarídeos/farmacologia , Neurônios/metabolismo , Palmitatos/farmacologia , Sirtuína 3/genética , Sirtuína 3/metabolismo
9.
Phys Chem Chem Phys ; 24(38): 23367-23381, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36129043

RESUMO

Photoelectron angular distributions (PADs) in SO- photodetachment using linearly polarized 355 nm (3.49 eV), 532 nm (2.33 eV), and 611 nm (2.03 eV) light were investigated via photoelectron imaging spectroscopy. The measurements at 532 and 611 nm access the X3Σ- and a1Δ electronic states of SO, whereas the measurements at 355 nm also access the b1Σ+ state. In aggregate, the photoelectron anisotropy parameter values follow the general trend with respect to electron kinetic energy (eKE) expected for π*-orbital photodetachment. The trend is similar to O2-, but the minimum of the SO- curve is shifted to smaller eKE. This shift is mainly attributed to the exit-channel interactions of the departing electron with the dipole moment of the neutral SO core, rather than the differing shapes of the SO- and O2- molecular orbitals. Of the several ab initio models considered, two approaches yield good agreement with the experiment: one representing the departing electron as a superposition of eigenfunctions of a point dipole-field Hamiltonian, and another describing the outgoing electron in terms of Coulomb waves originating from two separated charge centers, with a partial positive charge on the sulfur and an equal negative charge on the oxygen. These fundamentally related approaches support the conclusion that electron-dipole interactions in the exit channel of SO- photodetachment play an important role in shaping the PADs. While a similar conclusion was previously reached for photodetachment from σ orbitals of CN- (Hart, Lyle, Spellberg, Krylov, Mabbs, J. Phys. Chem. Lett., 2021, 12, 10086-10092), the present work includes the first extension of the dipole-field model to detachment from π* orbitals.

10.
Sci Rep ; 12(1): 15838, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151131

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is associated with increased oxidative stress that leads to hepatocyte and mitochondrial damage. In this study we investigated the mechanisms involved in the induction of oxidative stress and impairment of mitochondrial quality control and mitophagy in hepatocytes by the saturated fatty acid palmitate and Western diet feeding in mice and if their harmful effects could be reversed by the neurotrophic factor glial cell derived neurotrophic factor (GDNF). Western diet (WD)-feeding increased hepatic lipid peroxidation in control mice and, in vitro palmitate induced oxidative stress and impaired the mitophagic clearance of damaged mitochondria in hepatocytes. This was accompanied by reductions in hepatocyte sirtuin 3 (SIRT3) deacetylase activity, gene expression and protein levels as well as in superoxide dismutase enzyme activity. These reductions were reversed in the liver of Western diet fed GDNF transgenic mice and in hepatocytes exposed to palmitate in the presence of GDNF. We demonstrate an important role for Western diet and palmitate in inducing oxidative stress and impairing mitophagy in hepatocytes and an ability of GDNF to prevent this. These findings suggest that GDNF or its agonists may be a potential therapy for the prevention or treatment of NAFLD.


Assuntos
Fator Neurotrófico Derivado de Linhagem de Célula Glial , Hepatopatia Gordurosa não Alcoólica , Estresse Oxidativo , Sirtuína 3 , Animais , Dieta Hiperlipídica , Dieta Ocidental/efeitos adversos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Hepatócitos/metabolismo , Camundongos , Camundongos Transgênicos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Palmitatos/efeitos adversos , Sirtuína 3/genética , Sirtuína 3/metabolismo , Superóxido Dismutase/metabolismo
11.
Rev Sci Instrum ; 93(6): 065109, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778024

RESUMO

CHESS, chopper spectrometer examining small samples, is a planned direct geometry neutron chopper spectrometer designed to detect and analyze weak signals intrinsic to small cross sections (e.g., small mass, small magnetic moments, or neutron absorbing materials) in powders, liquids, and crystals. CHESS is optimized to enable transformative investigations of quantum materials, spin liquids, thermoelectrics, battery materials, and liquids. The broad dynamic range of the instrument is also well suited to study relaxation processes and excitations in soft and biological matter. The 15 Hz repetition rate of the Second Target Station at the Spallation Neutron Source enables the use of multiple incident energies within a single source pulse, greatly expanding the information gained in a single measurement. Furthermore, the high flux grants an enhanced capability for polarization analysis. This enables the separation of nuclear from magnetic scattering or coherent from incoherent scattering in hydrogenous materials over a large range of energy and momentum transfer. This paper presents optimizations and technical solutions to address the key requirements envisioned in the science case and the anticipated uses of this instrument.

12.
Sci Rep ; 12(1): 11164, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778409

RESUMO

Noonan syndrome is associated with complex lymphatic abnormalities. We report dynamic-contrast enhanced MR lymphangiography (DCMRL) findings in children and adults with Noonan syndrome to further elucidate this complex disease spectrum. A retrospective evaluation of patients with confirmed Noonan syndrome and clinical signs of lymphatic dysfunction undergoing DCMRL between 01/2019 and 04/2021 was performed. MRL included T2-weighted imaging (T2w) and DCMRL. Clinical history/presentation and genetic variants were recorded. T2w-imaging was evaluated for central lymphatic abnormalities and edema distribution. DCMRL was evaluated regarding the presence of cisterna chyli/thoracic duct, lymphatic leakages, pathological lymphatic reflux and abnormal lymphatic perfusion. The time from start of contrast-injection to initial enhancement of the thoracic duct venous junction was measured to calculate the speed of contrast propagation. Eleven patients with Noonan syndrome with lymphatic abnormalities (5 female, 6 male; 7 infants, 4 adults; mean age 10.8 ± 16.4 years) were identified (PTPN11 n = 5/11 [45.5%], RIT1 n = 5/11 [45.5%], KRAS n = 1/11 [9%]). Patients had a chylothorax (n = 10/11 [91%]) and/or pulmonary lymphangiectasia [dilated pulmonary lymph vessels] (n = 9/11 [82%]). Mediastinal/pulmonary edema was depicted in 9/11 (82%) patients. The thoracic duct (TD) was (partially) absent in 10/11 (91%) cases. DCMRL showed lymphatic reflux into intercostal (n = 11/11 [100%]), mediastinal (n = 9/11 [82%]), peribronchial (n = 8/11 [73%]), peripheral (n = 5/11 [45.5%]) and genital lymphatics (n = 4/11 [36%]). Abnormal pulmonary/pleural lymphatic perfusion was seen in 8/11 patients (73%). At infancy peripheral/genital edema was more prevalent in patients with RIT1 than PTPN11 (n = 3/5 vs. n = 0/5). Compared to patients with PTPN11 who had fast lymphatic enhancement in 4/5 patients, enhancement took markedly longer in 4/5 patients with RIT1-mutations. Thoracic duct dysplasia, intercostal reflux and pulmonary/pleural lymphatic perfusion are characteristic findings in patients with Noonan syndrome presenting with chylothorax and/or pulmonary lymphangiectasia. Central lymphatic flow abnormalities show possible phenotypical differences between PTPN11 and RIT1-mutations.


Assuntos
Quilotórax , Anormalidades Linfáticas , Síndrome de Noonan , Adolescente , Adulto , Criança , Quilotórax/diagnóstico por imagem , Feminino , Humanos , Lactente , Anormalidades Linfáticas/complicações , Anormalidades Linfáticas/diagnóstico por imagem , Anormalidades Linfáticas/genética , Linfografia/métodos , Masculino , Síndrome de Noonan/diagnóstico por imagem , Síndrome de Noonan/genética , Estudos Retrospectivos , Adulto Jovem
13.
Matrix Biol ; 111: 53-75, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35671866

RESUMO

Pulmonary hypertension (PH) comprises a diverse group of disorders that share a common pathway of pulmonary vascular remodeling leading to right ventricular failure. Development of anti-remodeling strategies is an emerging frontier in PH therapeutics that requires a greater understanding of the interactions between vascular wall cells and their extracellular matrices. The ubiquitous matrix glycan, hyaluronan (HA), is markedly elevated in lungs from patients and experimental models with PH. Herein, we identified HA synthase-2 (HAS2) in the pulmonary artery smooth muscle cell (PASMC) layer as a predominant locus of HA dysregulation. HA upregulation involves depletion of NUDT21, a master regulator of alternative polyadenylation, resulting in 3'UTR shortening and hyper-expression of HAS2. The ensuing increase of HAS2 and hyper-synthesis of HA promoted bioenergetic dysfunction of PASMC characterized by impaired mitochondrial oxidative capacity and a glycolytic shift. The resulting HA accumulation stimulated pro-remodeling phenotypes such as cell proliferation, migration, apoptosis-resistance, and stimulated pulmonary artery contractility. Transgenic mice, mimicking HAS2 hyper-synthesis in smooth muscle cells, developed spontaneous PH, whereas targeted deletion of HAS2 prevented experimental PH. Pharmacological blockade of HAS2 restored normal bioenergetics in PASMC, ameliorated cell remodeling phenotypes, and reversed experimental PH in vivo. In summary, our results uncover a novel mechanism of HA hyper-synthesis and downstream effects on pulmonary vascular cell metabolism and remodeling.


Assuntos
Metabolismo Energético , Hialuronan Sintases , Ácido Hialurônico , Hipertensão Pulmonar , Regiões 3' não Traduzidas/genética , Animais , Proliferação de Células , Metabolismo Energético/genética , Humanos , Hialuronan Sintases/genética , Hialuronan Sintases/metabolismo , Ácido Hialurônico/biossíntese , Hipertensão Pulmonar/enzimologia , Camundongos , Camundongos Transgênicos , Miócitos de Músculo Liso/enzimologia
14.
Neuroimage ; 258: 119372, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35700946

RESUMO

The ability to mentally wander away from the external environment is a remarkable feature of the human mind. Although recent years have witnessed a surge of interest in examining mind wandering using EEG, there is no comprehensive review that summarizes and accounts for the variable findings. Accordingly, we conducted a systematic review that synthesizes evidence from EEG studies that examined the electrophysiological measures of mind wandering. Our search yielded 42 studies that met eligibility criteria. The reviewed literature converges on a reduction in the amplitude of canonical ERP components (i.e., P1, N1 and P3) as the most reliable markers of mind wandering. Spectral findings were less robust, but point towards greater activity in lower frequency bands, (i.e., delta, theta, and alpha), as well as a decrease in beta band activity, during mind wandering compared to on-task states. The variability in these findings appears to be modulated by the task context. To integrate these findings, we propose an electrophysiological account of mind wandering that explains how the brain supports this inner experience. Conclusions drawn from this work will inform future endeavours in basic science to map out electrophysiological patterns underlying mind wandering and in translational science using EEG to predict the occurrence of this phenomenon.


Assuntos
Atenção , Encéfalo , Atenção/fisiologia , Encéfalo/fisiologia , Humanos
15.
Pathogens ; 11(2)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35215060

RESUMO

The innate immune response to P. aeruginosa pulmonary infections relies on a network of pattern recognition receptors, including intracellular inflammasome complexes, which can recognize both pathogen- and host-derived signals and subsequently promote downstream inflammatory signaling. Current evidence suggests that the inflammasome does not contribute to bacterial clearance and, in fact, that dysregulated inflammasome activation is harmful in acute and chronic P. aeruginosa lung infection. Given the role of mitochondrial damage signals in recruiting inflammasome signaling, we investigated whether mitochondrial-targeted therapies could attenuate inflammasome signaling in response to P. aeruginosa and decrease pathogenicity of infection. In particular, we investigated the small molecule, ZLN005, which transcriptionally activates peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), a master regulator of mitochondrial biogenesis, antioxidant defense, and cellular respiration. We demonstrate that P. aeruginosa infection promotes the expression of inflammasome components and attenuates several components of mitochondrial repair pathways in vitro in lung epithelial cells and in vivo in an acute pneumonia model. ZLN005 activates PGC-1α and its downstream effector, Sirtuin 3 (SIRT3), a mitochondrial-localized deacetylase important for cellular metabolic processes and for reactive oxygen species homeostasis. ZLN005 also attenuates inflammasome signaling induced by P. aeruginosa in bronchial epithelial cells and this action is dependent on ZLN005 activation of SIRT3. ZLN005 treatment reduces epithelial-barrier dysfunction caused by P. aeruginosa and decreases pathogenicity in an in vivo pneumonia model. Therapies that activate the PGC-1α-SIRT3 axis may provide a complementary approach in the treatment of P. aeruginosa infection.

16.
Sci Total Environ ; 816: 151534, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-34780821

RESUMO

Wastewater monitoring of SARS-CoV-2 presents a means of tracking COVID-19 community infection dynamics on a broader geographic scale. However, accounting for environmental and sample-processing losses may be necessary for wastewater measurements to readily inform our understanding of infection prevalence. Here, we present measurements of the SARS-CoV-2 N1 and N2 gene targets from weekly wastewater samples at three sites in Hamilton County, Ohio, during an increase and subsequent decline of COVID-19 infections. The concentration of N1 or N2 RNA in wastewater, measured over the course of six months, ranged from below the detection limit to over 104 gene copies/l, and correlated with case data at two wastewater treatment plants, but not at a sub-sewershed-level sampling site. We also evaluated the utility of a broader range of variables than has been reported consistently in previous work, in improving correlations of SARS-CoV-2 concentrations with case data. These include a spiked matrix recovery control (OC43), flow-normalization, and assessment of fecal loading using endogenous fecal markers (HF183, PMMoV, crAssphage). We found that adjusting for recovery, flow, and fecal indicators increased these correlations for samples from a larger sewershed (serving ~488,000 people) with greater industrial and stormwater inputs, but raw N1/N2 concentrations corresponded better with case data at a smaller, residential-oriented sewershed. Our results indicate that the optimal adjustment factors for correlating wastewater and clinical case data moving forward may not be generalizable to all sewersheds.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Prevalência , RNA , Águas Residuárias
18.
J Phys Chem Lett ; 12(41): 10086-10092, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34624197

RESUMO

The importance of including long-range electron-molecule interactions in treatments of photodetachment and/or photoionization is demonstrated. A combined experimental and computational study of CN- detachment is presented in which near threshold anisotropy parameters (ß) are measured via photoelectron imaging. Calculated ß values, based on an EOM-IP-CCSD/aug-cc-pVTZ Dyson orbital, are obtained using free-particle and point dipole models. The results demonstrate the influence of the molecular dipole moment in the detachment process and provide an explanation of the recently reported near threshold behavior of the overall photodetachment cross section in CN- detachment.

19.
20.
J Immunol ; 207(2): 483-492, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34193599

RESUMO

Alcohol use disorders (AUD) increase susceptibility to respiratory infections by 2- to 4-fold in part because of impaired alveolar macrophage (AM) immune function. Alcohol causes AM oxidative stress, diminishing AM phagocytic capacity and clearance of microbes from the alveolar space. Alcohol increases AM NADPH oxidases (Noxes), primary sources of AM oxidative stress, and reduces peroxisome proliferator-activated receptor γ (PPARγ) expression, a critical regulator of AM immune function. To investigate the underlying mechanisms of these alcohol-induced AM derangements, we hypothesized that alcohol stimulates CCAAT/enhancer-binding protein ß (C/EBPß) to suppress Nox-related microRNAs (miRs), thereby enhancing AM Nox expression, oxidative stress, and phagocytic dysfunction. Furthermore, we postulated that pharmacologic PPARγ activation with pioglitazone would inhibit C/EBPß and attenuate alcohol-induced AM dysfunction. AM isolated from human AUD subjects or otherwise healthy control subjects were examined. Compared with control AM, alcohol activated AM C/EBPß, decreased Nox1-related miR-1264 and Nox2-related miR-107, and increased Nox1, Nox2, and Nox4 expression and activity. These alcohol-induced AM derangements were abrogated by inhibition of C/EBPß, overexpression of miR-1264 or miR-107, or pioglitazone treatment. These findings define novel molecular mechanisms of alcohol-induced AM dysfunction mediated by C/EBPß and Nox-related miRs that are amenable to therapeutic targeting with PPARγ ligands. These results demonstrate that PPARγ ligands provide a novel and rapidly translatable strategy to mitigate susceptibility to respiratory infections and related morbidity in individuals with AUD.


Assuntos
Alcoolismo/tratamento farmacológico , Alcoolismo/metabolismo , Etanol/efeitos adversos , Macrófagos Alveolares/efeitos dos fármacos , Fagócitos/efeitos dos fármacos , Pioglitazona/farmacologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Masculino , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/metabolismo , Fagócitos/metabolismo
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