A 2-year data set of measured CCN (cloud condensation nuclei) concentrations at 0.2 % supersaturation is combined with aerosol size distribution and aerosol composition data to probe the effects of ...aerosol number concentrations, size distribution and composition on CCN patterns. Data were collected over a period of 2 years (2012-2014) in central Tucson, Arizona: a significant urban area surrounded by a sparsely populated desert. Average CCN concentrations are typically lowest in spring (233 cm
), highest in winter (430 cm
) and have a secondary peak during the North American monsoon season (July to September; 372 cm
). There is significant variability outside of seasonal patterns, with extreme concentrations (1 and 99 % levels) ranging from 56 to 1945 cm
as measured during the winter, the season with highest variability. Modeled CCN concentrations based on fixed chemical composition achieve better closure in winter, with size and number alone able to predict 82% of the variance in CCN concentration. Changes in aerosol chemical composition are typically aligned with changes in size and aerosol number, such that hygroscopicity can be parameterized even though it is still variable. In summer, models based on fixed chemical composition explain at best only 41% (pre-monsoon) and 36% (monsoon) of the variance. This is attributed to the effects of secondary organic aerosol (SOA) production, the competition between new particle formation and condensational growth, the complex interaction of meteorology, regional and local emissions and multi-phase chemistry during the North American monsoon. Chemical composition is found to be an important factor for improving predictability in spring and on longer timescales in winter. Parameterized models typically exhibit improved predictive skill when there are strong relationships between CCN concentrations and the prevailing meteorology and dominant aerosol physicochemical processes, suggesting that similar findings could be possible in other locations with comparable climates and geography.
Aerosol and cloud water measurements of dimethylamine (DMA), the most abundant amine in this study, were conducted in semi-arid (Tucson, Arizona) and marine (Nucleation in California Experiment, ...NiCE; central coast of California) areas. In both regions, DMA exhibits a unimodal aerosol mass size distribution with a dominant peak between 0.18 and 0.56 μm. Particulate DMA concentrations increase as a function of marine biogenic emissions, sulfate, BVOC emissions, and aerosol-phase water. Such data supports biogenic sources of DMA, aminium salt formation, and partitioning of DMA to condensed phases. DMA concentrations exhibit positive correlations with various trace elements and most especially vanadium, which warrants additional investigation. Cloud water DMA levels are enhanced significantly during wildfire periods unlike particulate DMA levels, including in droplet residual particles, due to effective dissolution of DMA into cloud water and probably DMA volatilization after drop evaporation. DMA:NH4+ molar ratios peak between 0.18 and 1.0 μm depending on the site and time of year, suggesting that DMA competes better with NH3 in those sizes in terms of reactive uptake by particles.
•DMA exhibits peak mass concentrations between 0.18 and 0.56 μm.•DMA:NH4+ molar ratios generally peak between 0.18 and 1.0 μm (up to 0.04).•DMA correlates with BVOCs, sulfate, aerosol water, and marine emissions.•Wildfires enhance DMA levels in cloud water via dissolution in drops.•DMA correlates with vanadium in PM1.0 in a populated semi-arid region.
Background
Central retinal artery occlusion (CRAO) is an ophthalmological emergency, the retinal analog of a stroke. To date there is no consensus or national guidelines on how this disorder should ...be managed. As academic neurologists and ophthalmologists treat CRAO frequently, we set out to understand how these clinicians approach patients with CRAO with a national survey.
Methods
We identified university-associated teaching hospitals offering vascular neurology, neuro-ophthalmology and/or retina fellowships in the US and asked the directors of the programs to respond to questions in an open response format to profile the acute management of CRAO at their institution.
Results
We found remarkable heterogeneity in the approach to acute treatment of patients with CRAO among the 45 institutions that responded to the survey. Only 20% had a formal policy, guideline or white paper to standardize the approach to treatment. The primary treating physician was an ophthalmologist, neurologist, or neuro-ophthalmologist 44, 27, and 4% of the time, respectively; 24% were co-managed acutely by neurology and ophthalmology. Intravenous fibrinolysis was offered to selected patients in 53% of institutions, and was the preferred initial treatment in 36%. When the acute treatment team involved a vascular neurologist, fibrinolysis was more likely to be considered a first-line treatment (
p
< 0.05). Anterior chamber paracentesis, ocular massage and hyperbaric oxygen therapy were offered 42, 66 and 7% of the time, respectively, while 9% of institutions offered no treatment. Anterior chamber paracentesis was more likely to be offered at programs where neurologists were not involved in treating CRAOs (
p
< 0.001). At 35% of institutions, patients with acute CRAO were not routinely referred to a general emergency room for initial evaluation and treatment. Carotid imaging was routinely obtained by 89% of programs, magnetic resonance imaging of the brain by 69%, echocardiogram by 62%, laboratory screening for an inflammatory state by 27% and retinal angiography by 30%. The thoroughness of vascular risk factors’ screening was greater in programs that routinely referred acute CRAO cases to the emergency department.
Conclusions
This survey shows that there is significant variability in treatment practices for acute CRAO in the US. Because of the high cerebrovascular and cardiovascular risk reported in this population of patients, it is notable that the approach to risk factor screening is also highly variable and many programs do not routinely refer patients to an emergency department for urgent evaluation. Finally, there appears to be equipoise among treatment teams regarding the efficacy of systemic fibrinolysis, as 53% of programs report a willingness to treat at least some patients with this modality.
Toll-like receptor-4 (TLR4) can be activated by nonbacterial agonists, including saturated fatty acids. However, downstream signaling pathways activated by nonbacterial agonists are not known. Thus, ...we determined the downstream signaling pathways derived from saturated fatty acid-induced TLR4 activation. Saturated fatty acid (lauric acid)-induced NFκB activation was inhibited by a dominant-negative mutant of TLR4, MyD88, IRAK-1, TRAF6, or IκBα in macrophages (RAW264.7) and 293T cells transfected with TLR4 and MD2. Lauric acid induced the transient phosphorylation of AKT. LY294002, dominant-negative (DN) phosphatidylinositol 3-kinase (PI3K), or AKT(DN) inhibited NFκB activation, p65 transactivation, and cyclooxygenase-2 (COX-2) expression induced by lauric acid or constitutively active (CA) TLR4. AKT(DN) blocked MyD88-induced NFκB activation, suggesting that AKT is a MyD88-dependent downstream signaling component of TLR4. AKT(CA) was sufficient to induce NFκB activation and COX-2 expression. These results demonstrate that NFκB activation and COX-2 expression induced by lauric acid are at least partly mediated through the TLR4/PI3K/AKT signaling pathway. In contrast, docosahexaenoic acid (DHA) inhibited the phosphorylation of AKT induced by lipopolysaccharide or lauric acid. DHA also suppressed NFκB activation induced by TLR4(CA), but not MyD88(CA) or AKT(CA), suggesting that the molecular targets of DHA are signaling components upstream of MyD88 and AKT. Together, these results suggest that saturated and polyunsaturated fatty acids reciprocally modulate the activation of TLR4 and its downstream signaling pathways involving MyD88/IRAK/TRAF6 and PI3K/AKT and further suggest the possibility that TLR4-mediated target gene expression and cellular responses are also differentially modulated by saturated and unsaturated fatty acids.
Background
Skin pH is one of the important physiological parameters of the skin. Changes in the pH play a role in the pathogenesis of several skin diseases, including acne.
Purpose
To assess the ...correlation between the pH and the age, and between the pH and the development of acne lesions, in a large acne patients group. We also evaluated the difference between the genders.
Methods
A total of 540 patients clinically diagnosed with acne vulgaris were included. The clinical digital photographs were taken, and the acne lesions were counted. The pH was measured, using the skin‐pH‐meter®. Area‐weighted pH was calculated and statistical analysis was performed, according to age and gender.
Results
The female had higher pH than the male acne patients. The T‐zone had higher pH than that of the U‐zone. In female acne patients, age and the area‐weight pH showed a positive correlation. Male acne patients had more inflammatory lesions. And U‐zone showed more acne lesions than T‐zone. There are negative correlations between the area‐weight pH and the number of acne lesions, in the T‐zone of the female acne patients and positive correlation at the inflammatory lesions on the T‐zone of male acne patients.
Conclusions
This is the first study to evaluate the correlations between pH, age, gender, and acne development in a large acne patients group using an objective, bioengineering method within the viewpoint of skin pH. We could expect that there are gender differences in the correlation between pH, age, and acne development. From this result, we could provide a clue to the treatment of acne, that maintaining the pH balance according to the difference of gender and age is an essential consideration.
Toll-like receptor 4 (TLR4) and TLR2 agonists from bacterial origin require acylated saturated fatty acids in their molecules. Previously, we reported that TLR4 activation is reciprocally modulated ...by saturated and polyunsaturated fatty acids in macrophages. However, it is not known whether fatty acids can modulate the activation of TLR2 or other TLRs for which respective ligands do not require acylated fatty acids. A saturated fatty acid, lauric acid, induced NFκB activation when TLR2 was co-transfected with TLR1 or TLR6 in 293T cells, but not when TLR1, 2, 3, 5, 6, or 9 was transfected individually. An n-3 polyunsaturated fatty acid (docosahexaenoic acid (DHA)) suppressed NFκB activation and cyclooxygenase-2 expression induced by the agonist for TLR2, 3, 4, 5, or 9 in a macrophage cell line (RAW264.7). Because dimerization is considered one of the potential mechanisms for the activation of TLR2 and TLR4, we determined whether the fatty acids modulate the dimerization. However, neither lauric acid nor DHA affected the heterodimerization of TLR2 with TLR6 as well as the homodimerization of TLR4 as determined by co-immunoprecipitation assays in 293T cells in which these TLRs were transiently overexpressed. Together, these results demonstrate that lauric acid activates TLR2 dimers as well as TLR4 for which respective bacterial agonists require acylated fatty acids, whereas DHA inhibits the activation of all TLRs tested. Thus, responsiveness of different cell types and tissues to saturated fatty acids would depend on the expression of TLR4 or TLR2 with either TLR1 or TLR6. These results also suggest that inflammatory responses induced by the activation of TLRs can be differentially modulated by types of dietary fatty acids.
Chimeric Antigen Receptor (CAR) T-cells have emerged as a powerful immunotherapy for various forms of cancer and show promise in treating HIV-1 infection. However, significant limitations are ...persistence and whether peripheral T cell-based products can respond to malignant or infected cells that may reappear months or years after treatment remains unclear. Hematopoietic Stem/Progenitor Cells (HSPCs) are capable of long-term engraftment and have the potential to overcome these limitations. Here, we report the use of a protective CD4 chimeric antigen receptor (C46CD4CAR) to redirect HSPC-derived T-cells against simian/human immunodeficiency virus (SHIV) infection in pigtail macaques. CAR-containing cells persisted for more than 2 years without any measurable toxicity and were capable of multilineage engraftment. Combination antiretroviral therapy (cART) treatment followed by cART withdrawal resulted in lower viral rebound in CAR animals relative to controls, and demonstrated an immune memory-like response. We found CAR-expressing cells in multiple lymphoid tissues, decreased tissue-associated SHIV RNA levels, and substantially higher CD4/CD8 ratios in the gut as compared to controls. These results show that HSPC-derived CAR T-cells are capable of long-term engraftment and immune surveillance. This study demonstrates for the first time the safety and feasibility of HSPC-based CAR therapy in a large animal preclinical model.
Abstract
The CAST-CAPP axion haloscope, operating at CERN inside the CAST dipole magnet, has searched for axions in the 19.74
μ
eV to 22.47
μ
eV mass range. The detection concept follows the ...Sikivie haloscope principle, where Dark Matter axions convert into photons within a resonator immersed in a magnetic field. The CAST-CAPP resonator is an array of four individual rectangular cavities inserted in a strong dipole magnet, phase-matched to maximize the detection sensitivity. Here we report on the data acquired for 4124 h from 2019 to 2021. Each cavity is equipped with a fast frequency tuning mechanism of 10 MHz/ min between 4.774 GHz and 5.434 GHz. In the present work, we exclude axion-photon couplings for virialized galactic axions down to
g
a
γ
γ
= 8 × 10
−14
GeV
−1
at the 90% confidence level. The here implemented phase-matching technique also allows for future large-scale upgrades.
Background
Enlarged facial pores have been esthetic problems and have become a matter of cosmetic concern. Several factors are supposed to be related to the enlargement of facial pores, although ...scientific evaluations were not performed yet.
Objective
To assess the correlation between facial pores and possible relating factors such as age, gender, sebum secretion, skin elasticity, and the presence of acne, using objective bioengineering instruments.
Methods
Sixty volunteers, 30 males and 30 females, participated in this study. Various parameters of facial pores were assessed using the Robo Skin Analyzer®. The facial sebum secretion and skin elasticity were measured using the Sebumeter® and the Cutometer®, respectively. These data were compared and correlated to examine the possible relationship between facial pores and age, sebum secretion and skin elasticity, according to gender and the presence of acne.
Results
Male gender and the existence of acne were correlated with higher number of facial pores. Sebum secretion levels showed positive correlation with facial pores. The R7 parameter of skin elasticity was negatively correlated with facial pores, suggesting increased facial pores with decreased skin elasticity. However, the age and the severity of acne did not show a definite relationship with facial pores.
Conclusion
Male, increased sebum and decreased skin elasticity were mostly correlated with facial pore development. Further studies on population with various demographic profiles and more severe acne may be helpful to elucidate the potential effect of aging and acne severity on facial pores.
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