A new method for studying activity and reaction kinetics of photocatalytic water oxidation systems using a bubbling reactor

A novel method is proposed for studying kinetics and overall activity of water oxidation (WO) catalysts using a bubbling reactor, where oxygen concentration is measured simultaneously in the liquid and in the gaseous phase. Total oxygen evolution is obtained from direct integration. The actual rate of oxygen formation as a function of time, RO2(t) not accessible to direct measurement with batch reactors, is calculated from raw data through a simple but comprehensive mathematical model, taking into account mass transfer phenomena occurring in the system. Data concerning the activity of a nanostructured Co3O4 catalyst dispersed on a mesoporous silica (MSU-H), in the presence of tris(2,2'-bipyridyl)Ruthenium [Ru(bpy)3]2+ as sensitizer and Na2S2O8 as sacrificial reactant, are used to illustrate data processing. Behaviour of the system is complicated by the occurrence, besides WO reaction, of the degradation of the sensitizer. Increase of sweeping gas flow increases RO2(t), by decreasing diffusional limitations to the reactions in the system: conditions for minimizing those were established. Data reported show that the assumption generally made of equilibrium between gaseous and liquid phase through Henry's law is incorrect, the more so the smaller the apparent mass transfer coefficient, kLa. An additional reason for removing oxygen from the liquid phase through bubbling is the occurrence of a parasitic reaction of molecular oxygen with the sensitizer. The method seems to yield reliable values of both kLa and the set of RO2(t) values: the former scales with the flow of sweeping gas, as expected; RO2(t) curves are in qualitative agreement with accepted reaction mechanisms. Results concerning RO2(t) lend support to our previous kinetic studies (M. Armandi et. al., ACS Catal. 2013, 3, 1272) where the reaction rate was assumed as constant for the first ~ 15 min. Availability of RO2(t) data not too biased by diffusional limitations opens the way to realistic studies of the kinetic features of WO heterogeneous reactions, in the present case as well as in many other

Endogenous Symmetric Dimethylarginine (SDMA) and Asymmetrical Dimethylarginine (ADMA) Levels in Healthy Cows and Cows with Subclinical and Clinical Mastitis. A Comparative Study

Mastitis is one of the most frequent diseases in dairy farms and occurs in both clinical and subclinical forms, resulting in substantial economic losses. Asymmetrical dimethylarginine (ADMA) and symmetrical dimethylarginine (SDMA) are biomarkers that inhibit nitric oxide synthesis. Elevated ADMA levels are associated with an increased risk of mortality both in human medicine and in dogs and a potential need for intensive care, while SDMA correlates with poor prognoses in humans and the progression of renal disease in horses, though its impact varies depending on renal function. This study examines the plasma levels of ADMA and SDMA in healthy cows (H) and cows with subclinical mastitis (SCM) and clinical mastitis (CM). Cows were classified as having mastitis when CMT > 1 and SCC ≥ 250,000 cells/mL. The SCM group showed no clinical signs or milk alterations, whereas the CM group exhibited udder and/or milk changes. The study included 196 blood samples to determine ADMA and SDMA concentrations, with 96 from healthy cows and 100 from pathological cows (58 SCM and 42 CM). The descriptive statistics were reported as the median because the data were not normally distributed (Shapiro–Wilk test). Data were analyzed using the Kruskal–Wallis test with Bonferroni post hoc correction, and the cut-off and accuracy index were calculated using the gold-standard measurement, the SCC. Statistically significant differences in ADMA levels were observed between healthy cows (0.11 μmol/L) and cows with mastitis (SCM 0.26 μmol/L; CM 0.26 μmol/L), but no differences were found in their SDMA levels. The cut-off for ADMA was >0.164 μmol/L, with a sensitivity of 80.41% and specificity of 77.78%. This study suggests that the blood concentration of ADMA is statistically higher in cows with subclinical and clinical mastitis and could be further explored as a potential biomarker for diagnosing these diseases

Cancer-associated CD43 glycoforms as target of immunotherapy

CD43 is a sialoglycosylated membrane protein that is involved in cell proliferation and differentiation. CD43 glycoforms that are recognized by the UN1 monoclonal antibody (mAb) were expressed in lymphoblastoid T-cell lines and solid tumors, such as breast, colon, gastric, and squamous cell lung carcinomas, while unexpressed in the normal counterparts. The cancer association of UN1/CD43 epitope suggested the possibility to use the UN1 mAb for tumor diagnosis and therapy. In this study, we show that the UN1 mAb was endowed with antitumor activity in vivo because its passive transfer inhibited the growth of UN1-positive HPB-ALL lymphoblastoid T cells in mice. Furthermore, we demonstrate that tumor inhibition was due to UN1 mAb-dependent natural killer-mediated cytotoxicity. By screening a phage-displayed random peptide library, we identified the phagotope 2/165 as a mimotope of the UN1 antigen, as it harbored a peptide sequence that was specifically recognized by the UN1 mAb and inhibited the binding of the UN1 mAb to UN1-positive tumor cells. On the basis of sequence homology with the extracellular region of CD43 (amino acids 64 to 83), the 2/165 peptide sequence was likely mimicking the protein core of the UN1/CD43 epitope. When used as vaccine in mice, the 2/165 phagotope raised antibodies against the UN1/CD43 antigen, indicating that the 2/165 phagotope mimicked the UN1 antigen structure, and could represent a novel immunogen for cancer immunotherapy. These findings support the feasibility of using monoclonal antibodies to identify cancer-associated mimotopes for immunotherapy

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

pHyloGASTRO in the Treatment of Equine Gastric Ulcer Lesions

Equine gastric ulcer syndrome (EGUS) is the most common disease of the equine stomach with high prevalence of both squamous and glandular disease reported in various populations. The aim of this study was to evaluate the effectiveness of a phytotherapic compound (pHhyloGASTRO) in the therapy of EGUS. The study was performed as a randomized double-blinded single-center study. The study population was composed of 19 equids which were submitted to gastroscopy before and after a 6-week treatment with feed additive (10/19) (pHyloGASTRO, 4Union B.I.O. srl, Italy) or a placebo (9/19). Severity grade was evaluated on a scale from 0 to 4. The variables of interest were gastric lesion score and improvement grade. Changes and comparisons of variables were performed by contingency table analyses. P level of significance was set at .05 in all analyses. In terms of gastric lesion scores, the treated group improved significantly compared to the placebo group. pHyloGASTRO seems to be effective in the treatment of EGUS. Further studies are needed to verify whether prolonged administration of pHyloGASTRO could be more effective in completely healing gastric lesions