Ag Treatment Research Articles

Mitigating acid rain stress and enhancing aquaponics lettuce quality through root protection

Aquaponics is a sustainable eco-agricultural technology that combines aquaculture with horticulture. However, there is still limited research on the effects and preventive measures of acid rain on aquaponics vegetables. Herein, we conducted an experiment to decipher the combined effect of acid rain (pH 5.0, 4.0, and 3.0) and the protecting treatments (AR and AG) on the lettuce, in which plant growth, photosynthetic system, antioxidant system, nutrition and mineral elements were investigated. The results indicated that acid rain was the main factor affecting the growth of lettuce. Without acid rain, the various indicators of lettuce did not alter under AR and AG treatments. As pH decreased, lettuce yield and quality gradually decreased. Acid rain stimulated the antioxidant system and reduced root vitality and nutrient absorption. AG treatment mitigated the harm of acid rain on lettuce root vitality, soluble sugars, nitrate, and ascorbic acid content. At pH 4.0, AG treatment had the greatest mitigating effect. While at pH 3.0, AG treatment had no effect on the SOD activity, total phenolic and soluble sugar content of lettuce. These findings indicated that protecting the roots can mitigate the impact of acid rain on the edible and nutritional value of aquaponics lettuce. As pH decreased, this mitigating effect gradually diminished. In summary, the detrimental effect of acid rain on aquaponics lettuce was inevitable, yet protective root treatments offered a viable strategy to mitigate this stress. This research established a foundation for the enhancement of aquaponics systems resilience to acid rain.

Modifying back contact by silver to Enhance the performance of carbon-based Sb2S3 solar cells

Antimony sulfide (Sb2S3) has drawn significant attention due to its excellent photoelectric properties. However, the photon conversion efficiency of Sb2S3 solar cell is limited by its magnificent value band offset between absorber layer and carbon electrode. Herein, a back surface optimization strategy is developed to reduce the barrier at the back contact. By introducing Ag at back contact before post-selenization process, the Valence-Band Maximum (VBM) of Sb2S3 is elevated under the action of spin–orbit interaction between Sb-5 s orbit and Ag-d orbit, leading to improve the extraction of holes. Consequently, the electrical conductivity of the film undergoes a significant improvement, rising from 1.20 × 10-5 to 1.59 × 10-5 S/cm. Additionally, the film surface morphology is refined, exhibiting a reduction in roughness from 17.1 nm to 13.6 nm, which leads to less leak current generated. Finally, the device based on FTO/SnO2/CdS/Sb2S3/Carbon structure achieved the power conversion efficiency (PCE) of 5.51 %, representing a 16 % improvement compared to the device without Ag treatment.

Cerebroprotective Potential of Andrographolide Nanoparticles: In silico and In vivo Investigations.

Ischemic stroke remains the leading cause of death and disability, while the main mechanisms of dominant neurological damage in stroke contain oxidative stress and inflammation. Docking studies revealed a binding energy of - 6.1 kcal/mol for AG, while the co-crystallized ligand (CCl) exhibited a binding energy of - 7.3 kcal/mol with NOS. AG demonstrated favourable hydrogen bond interactions with amino acids ASN A:354 and ARG A:388 and hydrophobic interactions with GLU A:377. Molecular dynamics simulations throughout 100 ns indicated a binding affinity of - 27.65±2.88 kcal/mol for AG, compared to - 18.01±4.02 kcal/mol for CCl. These findings suggest that AG possesses a superior binding affinity for NOS compared to CCl, thus complementing the stability of NOS at the docked site.AG has limited applications owing to its low bioavailability, poor water solubility, and high chemical and metabolic instability.The fabrication method was employed in the preparation of AGNP, SEM analysis confirmed spherical shape with size in 19.4±5 nm and investigated the neuroprotective effect in cerebral stroke rats induced by 30 min of carotid artery occlusion followed by 4 hr reperfusion, evaluated by infarction size, ROS/RNS via GSH, MPO, NO estimationand AchE activity, and monitoring EEG function. Cortex and hippocampal histology were compared between groups. AGNP treatment significantly decreased Infarction size and increased GSH levels (p<0.01**), decreased MPO (p<0.01**), NO (p<0.01**), AchE (p<0.01**), restored to normal EEG amplitude, minimizing unsynchronized polyspikes and histological data revealed that increased pyramidal cell layer thickness and decreased apoptotic neurons in hippocampus, cortex appeared normal neurons with central large vesicular nuclei, containing one or more nucleoli in compared to AG treatment. Based on brain biochemical, histopathology reports AGNP exhibited significant cerebroprotective activity compared to AG on ischemic rats.

Cross-hierarchical analysis of self-assembly dynamics in enzyme-treated rice gel during retrogradation

The purpose of this study was to elucidate the self-assembly dynamics of rice gel and their influence on the physical properties of enzyme-treated rice starch during storage using a cross-hierarchical analytical approach. Two enzymes, α-glucosidase (AG) and branching enzyme (BE), were used in this study. Changes in the physical properties of rice gel during storage showed that, compared to the control, the increase in G′ and G″ for AG-treated gels was lower during storage, and that the change in tanδ of AG-treated gels was lower at 0.1 Hz. Small angle X-ray scattering and ultra-small angle X-ray scattering analyses revealed that the radius of gyration of the primary aggregates was not affected by enzyme treatment, but that the rate of increase in the radius of gyration of secondary aggregates was faster in both enzyme-treated gels. Atomic force microscopy revealed that AG treatment changed the shape of the extended clusters, while BE treatment changed the connecting structure of the extended clusters. The results showed that AG and BE treatment affected the mesoscale intermolecular and intramolecular self-assembly dynamics of rice gel, causing changes in its physical properties.

Phosphorus fractions affect fungal compositions and functions under land use conversions in saline-alkali soil in northeastern China

BackgroundLittle is known about the link between the fungal community and phosphorus fractions when land use is converted from cropland to grassland in saline-alkali soil in northeastern China. Therefore, in this study, the diversity, composition, and function of fungi, as well as phosphorus fractions including Olsen-P and inorganic phosphorus (Pi), were investigated under land use conversions from maize cropland (MC) to alfalfa (Medicago sativa L.) (AG), Leymus chinensis (LG), and natural restored grasslands (RG).ResultsThe results showed that the Pi fractions of Ca8-P, Fe-P, Ca2-P, and Ca10-P were closely related with Olsen-P. Significantly increased Olsen-P content was found in 0–10 cm soil layer in the AG treatment, relative to LG and RG treatments (P < 0.05). The occluded P content in 0–10 cm and the Al-P content in 10–20 cm in the RG treatment were the highest. The RG treatment increased the Shannon index of fungi, as well as the abundances of phyla Mortierellomycota and phyla Glomeromycota. Higher abundance of genus Mortierella and lower abundance of genus Cladosporium were observed at RG treatment. Moreover, the RG treatment greatly reduced the abundance of plant pathogens and enhanced the abundances of mycorrhizal and ectomycorrhizal. The Olsen-P was positively correlated with the abundance of plant pathogen (P < 0.01), and the Olsen-P, Ca2-P, and Fe–P were negatively correlated with both the abundances of mycorrhizal and ectomycorrhizal (P < 0.05).ConclusionLand use conversion from maize cropland to natural restored grassland could reduce plant pathogens and enhance useful fungi by decreasing the availability of phosphorus.Graphical

Agri‐mat and grass mulch effect on crop biomass yield in sandy loam and loam soils

AbstractThe role of agri‐mat mulch as a soil and water conservation technology for improved and sustainable plant production has not been explored. The aim of the study was to investigate the effects of agri‐mats and grass mulch on crop biomass yield of maize and spinach under sandy loam and loam soils. The following five mulch treatments were established in two sites (Durban with loam soil and Pretoria with sandy loam soil) during the 2017/18 and 2018/19 planting seasons: (a) full agri‐mat mulch cover (100%AG), (b) half agri‐mat mulch cover, (c) bare (control), (d) six tons of grass mulch per hectare (6t.GM), and (e) three tons of grass mulch per hectare. Crop growth parameters such as number of leaves, leaf length, plant height, and crop biomass yield were measured in both planting seasons. The results indicate that the crop biomass yield (both spinach and maize) was higher under 100%AG treatment compared to other mulching treatments followed by 6t.GM in the Pretoria site. For the Durban site, the highest crop growth parameters and biomass yield for both spinach and maize was recorded under the 100%AG treatment. The 100%AG treatment produced 33% more spinach biomass yield during the 2018 growing season in Durban compared with the 6t.GM treatment, with no percentage differences in the 2019 growing season. In Pretoria, there was a 20% (2018) and 32% (2019) difference in spinach biomass yield between the highest and second‐highest performing treatments. As hypothesized, agri‐mats can effectively improve crop biomass yields in semiarid and humid agro‐ecological zones with different soil types.

Alcohol in gel is as effective as chlorhexidine in the reduction of microbiota on hands in hospital nurses

Context: Alcohol gel (70% ethanol, AG) and 2% chlorhexidine foam (CF) are hand antiseptics recommended by the World Health Organization. Although both are effective, it is unclear if one is superior to the other in a hospital setting. Aims: To evaluate the disinfectant ability comparing AG and CF by analyzing microbial reduction on the hands of nursing staff from two hospitals in Northern Peru. Methods: The nursing staff was randomly assigned to the AG and CF treatment groups. Before and after antisepsis, samples were taken by inserting the hands into a sterile self-closing bag containing peptone water. A sample of the liquid medium was plated on agar and used to calculate the CFU/mL of the peptone water. Participant data was analyzed in aggregate or according to hospital, profession, or service. Results: Both AG and CF were significantly effective in reducing CFU/mL. In aggregate, CFU/mL reduction was 80.9% for AG and 91.3% for CF, but the difference was not statistically significant. However, a small statistically significant difference in favor of CF was observed in the surgical center of both hospitals. These results are confirmed with multivariate analysis. Conclusions: AG and CF are both effective in hand antisepsis, but other factors are important when deciding which agent is appropriate for a specific healthcare setting.

Clinical Significance of Increased Skeletal Muscle Mass During Nab-Paclitaxel Plus Gemcitabine Treatment in Patients With Advanced Pancreatic Cancer.

The clinical significance of increased skeletal muscle mass during nab-paclitaxel plus gemcitabine (AG) treatment in patients with advanced pancreatic cancer (APC) remains unknown. Therefore, we retrospectively investigated the characteristics of patients after AG treatment to evaluate the clinical significance of increased skeletal muscle mass during treatment. From January 2015 to August 2021, 67 patients with APC received AG as first-line chemotherapy at Higashiosaka City Medical Center. Of these patients, 39 received second-line (2L) chemotherapy after AG therapy, and 28 received best supportive care. Patients' characteristics at the end of AG treatment were compared retrospectively between these 2 groups, and the relevant factors at the end of first-line treatment for 2L chemotherapy induction were analyzed. A performance status of 0 to 1 and increased skeletal muscle mass during AG therapy were independently associated with 2L chemotherapy induction in multivariate analysis. A high relative dose intensity (≥50%) in the first 8 weeks of AG treatment was more frequently found in patients with increased skeletal muscle mass during treatment ( P = 0.037). Increased skeletal muscle mass during AG treatment might contribute to the higher prevalence of 2L chemotherapy induction in patients with APC.

Novel mechanism of the COVID-19 associated coagulopathy (CAC) and vascular thromboembolism

Previous studies from our laboratory revealed that SARS-CoV-2 spike protein (SP) administration to a genetically engineered model expressing the human angiotensin-converting enzyme 2; ACE2 receptor (i.e., hACE2 humanized mouse) mimicked the coronavirus disease-19 (COVID-19) pathology. In humans the cause of high morbidity, and mortality is due to ‘cytokine-storm’ led thromboembolism; however, the exact mechanisms of COVID-19 associated coagulopathy (CAC) have yet to be discovered. Current knowledge suggests that CAC is distinct from the standard coagulopathy, in that the intrinsic and extrinsic thrombin-dependent coagulation factors, and the pathway(s) that are common to coagulopathy, are not recruited by SARS-CoV-2. Findings from patients revealed that there is little change in their partial thromboplastin, or the prothrombin time coupled with a significant decline in platelets. Further, there appears to be an endothelial dysfunction during COVID-19 suggesting an interaction of the endothelia with immune cells including neutrophils. There are also reports that inflammatory NGAL is elevated during COVID-19. Furthermore, the levels of NPT are also increased indicating an increase in inflammatory M1 macrophage iNOS which sequesters BH4; an essential enzyme co-factor that acts as a potent antioxidant thus causing damage to endothelia. SARS-CoV-2 entry into the host cells is facilitated by a co-operative action between TMPRSS2 and the main ACE2 receptor. Interestingly, after infection ADAMTS13; a von Willebrand factor; VWF cleaving enzyme is found to be decreased. Based on these facts, we hypothesize that vascular thromboembolism is associated with serine and metalloproteinase, and in that context, we opine that inhibition of iNOS might help mitigate COVID-19 harmful effects. To test this hypothesis, we administered SP to the hACE2 mice that were subsequently treated with amino guanidine (AG; a potent inhibitor of glycoxidation, lipoxidation and oxidative vicious cycles). Our results revealed increase in TMPRSS2, and NGAL by SP but treatment with AG mitigated their levels. Similarly, levels of MMP-2, and -9 were increased; however, AG treatment normalized these levels. Our findings suggest that occurrence of CAC is influenced by TMPRSS2, ADAMTS13, NGAL and MMP- 2, and -9 factors, and an intervention with iNOS blocker helped mitigate the CAC condition in experimental settings.

L-Aminoguanidine Induces Imbalance of ROS/RNS Homeostasis and Polyamine Catabolism of Tomato Roots after Short-Term Salt Exposure.

Polyamine (PA) catabolism mediated by amine oxidases is an important process involved in fine-tuning PA homeostasis and related mechanisms during salt stress. The significance of these amine oxidases in short-term responses to salt stress is, however, not well understood. In the present study, the effects of L-aminoguanidine (AG) on tomato roots treated with short-term salt stress induced by NaCl were studied. AG is usually used as a copper amine oxidase (CuAO or DAO) inhibitor. In our study, other alterations of PA catabolism, such as reduced polyamine oxidase (PAO), were also observed in AG-treated plants. Salt stress led to an increase in the reactive oxygen and nitrogen species in tomato root apices, evidenced by in situ fluorescent staining and an increase in free PA levels. Such alterations were alleviated by AG treatment, showing the possible antioxidant effect of AG in tomato roots exposed to salt stress. PA catabolic enzyme activities decreased, while the imbalance of hydrogen peroxide (H2O2), nitric oxide (NO), and hydrogen sulfide (H2S) concentrations displayed a dependence on stress intensity. These changes suggest that AG-mediated inhibition could dramatically rearrange PA catabolism and related reactive species backgrounds, especially the NO-related mechanisms. More studies are, however, needed to decipher the precise mode of action of AG in plants exposed to stress treatments.

Leaf chlorophyll fluorescence and reflectance of oakleaf lettuce exposed to metal and metal(oid) oxide nanoparticles

BackgroundMost nanoparticles (NPs) have a significant impact on the structure and function of the plant photosynthetic apparatus. However, their spectrum of action varies significantly, from beneficial stimulation to toxicity, depending on the type of NPs, the concentration used and plant genotypic diversity. Photosynthetic performance can be assessed through chlorophyll a fluorescence (ChlF) measurements. These data allow to indirectly obtain detailed information about primary light reactions, thylakoid electron transport reactions, dark enzymatic stroma reactions, slow regulatory processes, processes at the pigment level. It makes possible, together with leaf reflectance performance, to evaluate photosynthesis sensitivity to stress stimuli. ResultsWe investigated effects of different metal and metal(oid) oxide nanoparticles on photosynthesis of oakleaf lettuce seedlings by monitoring the chlorophyll a fluorescence light radiation and reflectance from the leaves. Observations of ChlF parameters and changes in leaf morphology were carried out for 9 days in two-day intervals. Spectrophotometric studies were performed at 9th day. Suspensions of NPs with the following concentrations were used: 6% TiO2, SiO2; 3% CeO2, SnO2, Fe2O3; 0.004% (40 ppm) Ag; 0.002% (20 ppm) Au. Nanoparticles were applied directly on the leaves which caused small symptoms of chlorosis, necrosis and leaf veins deformation, but the plants fully recovered to the initial morphological state at 9th day. Leaf reflectance analysis showed an increase in FRI for SiO2-NPs and CeO2-NPs treatments and ARI2 for Fe2O3, however, WBI and PRI coefficients for the latter nanoparticle were lower than in control. Chlorophyll a fluorescence parameters have changed due to NPs treatment. Fe2O3-NPs caused an increase in Fv/F0, PIABS, ET0/RC, DI0/RC, ABS/RC in different time points in comparison to control, also Ag, Au and SnO2 treatment caused an increase in Fv/F0, PIABS or ET0/RC, respectively. On the other hand, TiO2-NPs caused a decrease in Fv/Fm and Fv/F0 parameters, but an increase in DI0/RC value was observed. SnO2-NPs decreased PIABS, but increased ET0/RC than compared to control. Nanoparticles affected the shape of the O-J-I-P curve in slight manner, however, further analyses showed unfavourable changes within the PSII antenna, manifested by a slowdown in the transport of electrons between the Chl molecules of the light-harvesting complex II and the active center of PSII due to NPs application.ConclusionChanges in ChlF parameters and leaf reflectance values clearly proved the significant influence of NPs on the functioning of the photosynthetic apparatus, especially right after NPs application. The nature of these changes was strictly depended on the type of nanoparticles and sometimes underwent very significant changes over time. The greatest changes in ChlF parameters were caused by Fe2O3 nanoparticles, followed by TiO2-NPs. After slight response of O-J-I-P curves to treatment of the plants with NPs the course of the light phase of photosynthesis stabilized and at 9th day were comparable to the control curve.

Abstract 2781: Mechanism study of surufatinib on the optimized strategy of AG plus PD-1 antibody treatment in pancreatic cancer

Abstract Background: Gemcitabine combined with albumin-bound paclitaxel (AG) is the standard treatment for pancreatic cancer. However, it provides no benefit after combined AG with PD-1 antibody, which needs to be optimized urgently. Surufatinib (SUR) is a novel small-molecule inhibitor that observably inhibits VEGFR 1, 2, 3, fibroblast growth factor receptor 1 (FGFR 1), and colony stimulating factor-1 receptor (CSF-1R), which simultaneously shows anti-angiogenic activity and immune microenvironment activation. Herein, we aimed to explore the synergistic effect and related mechanism of SUR plus AG and PD-1 antibody (SAP) regimen. Methods: Surgical tumor specimens were collected and analyzed using single-cell sequencing and immunohistochemistry technology. Orthotopic transplantation mice model of pancreatic cancer and co-culture system of pancreatic cancer cells and tumor-associated macrophages (TAMs) were successively established to reveal the potential molecular mechanism of SUR in optimizing the effects of AG plus PD-1 antibody, by western blot, immunofluorescence and ubiquitination experiments. Results: Tumor CSF-1 levels were markedly promoted in pancreatic cancer patients after the treatment of gemcitabine, while an increased infiltration of M2 polarized TAMs (M2-TAMs) was induced. A time-dependent upregulation of M2-TAMs infiltration and PD-L1 expression were also observed after the treatment of AG regimen, which might interfere the therapeutic benefits of AG plus PD-1. In co-culture system, tumor PD-L1 expression levels were distinctly down-regulated after the treatment of SAP regimen, while the decreased infiltration of M2-TAMs was observed. In pancreatic cancer cell, PD-L1 protein synthesis were obviously inhibited by SUR, instead of PD-L1 mRNA expression. After the pancreatic cancer cells pretreated with cycloheximide to inhibit protein synthesis, the half-life period of PD-L1 was ulteriorly reduced by SUR. Inversely, the inhibitory action of SUR on PD-L1 expression was reversed by proteasome inhibitor PS-341, rather than lysosomal inhibitor chloroquine. As a result, it indicated that the protein stability of PD-L1 might interfered by SUR via ubiquitin-proteasome pathway. Particularly, when compared with AG plus PD-1 antibody treatment in tumor-bearing model, SAP regimen significantly down-regulated the expression levels of CSF1R, CD163 and PD-L1, and inhibited tumor growth by promoting tumor cell apoptosis and improving the tumor immune microenvironment. Conclusions: Forceful evidence supported that PD-L1 expression could be interfered by surufatinib via ubiquitin-proteasome pathway and M2-TAMs regulation. Herein, additional administration of surufatinib might improve the immunosuppression and drug resistance caused by AG, and increase the curative effect of AG plus PD-1 antibody treatment in clinical practice. Citation Format: Song Gao, Wenbo Zhu, Xiaofan Guo, Yuexiang Liang, Hongwei Wang, Peijun Xu, Yuning Song, Jihui Hao, Shaoshi Wen, Xing Lv, Jiancai Zhou. Mechanism study of surufatinib on the optimized strategy of AG plus PD-1 antibody treatment in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2781.

What drives soil degradation after gravel mulching for 6 years in northwest China?

Gravel mulch is an agricultural water conservation practice that has been widely used in the semi-arid region of northwest China, but its effectiveness is now lessening due to soil degradation caused by long-term gravel mulching. In this study, we report on a 6-year-long gravel mulch experiment conducted in the northwestern Loess Plateau to evaluate the impact of gravel mulch on soil physicochemical properties and microbial communities, with the objective of clarifying the causes of long-term gravel mulching-induced land degradation. After 6 years mulching, we found that gravel mulched soil contained significantly higher concentrations of total carbon and total organic carbon than non-mulched soil (control). Long-term gravel mulching significantly changed the soil microbial diversity and abundance distribution of bacterial and fungal communities. Notably, the relative abundance of Acidobacteria was significantly higher under gravel mulching than the control (no mulching), being significantly greater in the AG treatment (small-sized gravel, 2-5 mm) than all other treatments. Conversely, the relative abundance of Actinobacteria was significantly lower under gravel mulching than the control, being the lowest in the BG treatment (large-sized gravel, 40-60 mm). At the same time, the relative abundance of Bacteroidetes was significantly lower in AG yet higher in BG vis-à-vis the other treatments. Of the various factors examined, on a 6-year scale, the capture of dust by gravel mulch and altered carbon and nitrogen components in soil play major contributing roles in the compositional change of soil microorganisms. These results suggest that modified soil material input from gravel mulching may be the key factor leading to soil degradation. More long-term experimental studies at different sites are now needed to elucidate the mechanisms responsible for soil degradation under gravel mulching.

Improvement of Stevia rebaudiana Bertoni In Vitro Propagation and Steviol Glycoside Content Using Aminoacid Silver Nanofibers.

The food industry is interested in replacing artificial sweeteners with natural sugars that possess zero calories and carbohydrates and do not cause spikes in blood sugar levels. The steviosides leaves, synthesized at Stevia rebaudiana Bertoni, are 300 times sweeter than common table sugar. Stevia propagation is limited due to the poor viability of the seeds, the long time and low germination rate, and the poor rooting ability of vegetative cuttings. Because of this, an alternative biotechnological method for its reproduction is being studied, such as multiple shoot production through direct organogenesis using nanofibers, formed from a derivative of amino acid valine as a carrier of the biologically active agent silver atoms/particles (NF-1%Ag and NF-2%Ag). The stevia explants were cultured on a medium containing NF-1%Ag and NF-2%Ag at concentrations of 1, 10, 50, and 100 mg L−1. The NF-1%Ag and NF-2%Ag treatment caused hormetic effects on stevia plantlets. At low concentrations of from 1 to 50 mg L−1 of nanofibers, the stimulation of plant growth was observed, with the maximum effect being observed at 50 mg L−1 nanofibers. However, at the higher dose of 100 mg L−1, inhibition of the values of parameters characterizing plant growth was recorded. The presence of nanofibers in the medium stimulates stevia root formatting.

Effects of Trace Ag and Heat Treatment on the Mechanical Properties and Corrosion Resistance of Al-Zn-Mg-Cu Alloys

Effects of Trace Ag and Heat Treatment on the Mechanical Properties and Corrosion Resistance of Al-Zn-Mg-Cu Alloys

MiR-146a Maintains Immune Tolerance of Kupffer Cells and Facilitates Hepatitis B Virus Persistence in Mice.

Kupffer cells (KCs), the largest tissue-resident macrophage population in the body, play a central role in maintaining a delicate balance between immune tolerance and immunity in the liver. However, the underlying molecular mechanism remains elusive. In this study, we show that KCs express high levels of miR-146a, which is under control of the PU.1 transcription factor. miR-146a deficiency promoted KCs differentiation toward a proinflammatory phenotype; conversely, miR-146a overexpression suppressed this phenotypic differentiation. We found that hepatitis B virus (HBV) persistence or HBV surface Ag treatment significantly upregulated miR-146a expression and thereby impaired polarization of KCs toward a proinflammatory phenotype. Furthermore, in an HBV carrier mouse model, KCs depletion by clodronate liposomes dramatically promoted HBV clearance and enhanced an HBV-specific hepatic CD8+ T cell and CD4+ T cell response. Consistent with this finding, miR-146a knockout mice cleared HBV faster and elicited a stronger adaptive antiviral immunity than wild-type mice. In vivo IL-12 blockade promoted HBV persistence and tempered the HBV-specific CTL response in the liver of miR-146a knockout mice. Taken together, our results identified miR-146a as a critical intrinsic regulator of an immunosuppressive phenotype in KCs under inflammatory stimuli, which may be beneficial in maintenance of liver homeostasis under physiological condition. Meanwhile, during HBV infection, miR-146a contributed to viral persistence by inhibiting KCs proinflammatory polarization, highlighting its potential as a therapeutic target in HBV infection.

Baseline Factors Predictive of the Receipt of Second-Line Chemotherapy After Nab-Paclitaxel Plus Gemcitabine for Patients With Advanced Pancreatic Cancer

Second-line (2L) chemotherapy is important for improved survival in patients with advanced pancreatic cancer (APC). However, approximately half of patients with APC do not receive 2L chemotherapy because of disease progression or adverse events. Baseline factors predictive of the receipt of 2L chemotherapy remain unknown. Therefore, we investigated predictive factors for the receipt of 2L chemotherapy in patients with APC. Between January 2015 and March 2020, 53 patients with APC received nab-paclitaxel plus gemcitabine (AG) as first-line chemotherapy at our institute. Of these 53 patients, 29 patients received 2L chemotherapy, and 23 patients received best supportive care. Patients' characteristics were compared retrospectively, and predictive factors for the receipt of 2L chemotherapy were evaluated. Sarcopenia and hypoalbuminemia at baseline were independent negative predictive factors for the receipt of 2L chemotherapy in multivariate analysis. Although the presence of sarcopenia did not affect the relative dose intensity through 8 weeks of AG therapy, patients with hypoalbuminemia had a significantly lower relative dose intensity. Sarcopenia and hypoalbuminemia at baseline might be negative predictive factors for the receipt of 2L chemotherapy after AG treatment in patients with APC.

The Efficacy and Safety of PD-1 Inhibitors Combined with Nab-Paclitaxel Plus Gemcitabine versus Nab-Paclitaxel Plus Gemcitabine in the First-Line Treatment of Advanced Pancreatic Cancer: A Retrospective Monocentric Study.

PurposeThe purpose of this study was to evaluate the efficacy and safety of PD-1 inhibitor combined with nab-paclitaxel plus gemcitabine (AG) chemotherapy versus AG chemotherapy in the first-line treatment of advanced pancreatic cancer.Patients and MethodsThis study included the application of AG treatment and PD-1 combined with AG treatment with advanced pancreatic ductal adenocarcinoma at the Affiliated Hospital of Qingdao University from September 2018 to July 2020. Clinical information and next-generation sequencing (NGS) reports of patients were collected to compare the effectiveness and adverse events of the two treatments and analyze the risk factors affecting the prognosis of patients.ResultsThere was no difference in PFS between the AG group and the PD-1+AG group (4.9 months vs 5.0 months, P = 0.154), but the difference in OS was statistically significant (9.3 months vs 12.1 months, P < 0.001). Compared with the AG group, the PD-1+AG group reduced the risk of death about 20.0% (HR = 0.203, 95% CI, 0.090−0.459, P < 0.001). In terms of safety, the incidence of hypothyroidism and reactive skin capillary hyperplasia in PD-1 + AG group was higher than that in AG group (P < 0.050) in grade 1–2; grade 3–4 adverse reactions were mainly hematologic AEs and abnormal liver function. The incidence of grade 3–4 adverse reactions in the two groups was 38.7% (95% CI, 20.5–56.9%) and 35.3% (95% CI, 10.0–60.6%), respectively. In addition, PD-1+ AG regimen improved the OS of patients with KRAS and TP53 co-mutations (8.0months vs 10.2 months, P = 0.004).ConclusionPD-1 inhibitors combined with AG chemotherapy have shown good efficacy and safety in the first-line treatment of patients with advanced pancreatic ductal adenocarcinoma. This regimen similarly improved OS in patients with KRAS and TP53 co-mutations.

A Comparative Study between the Use of Negative Pressure Wound Therapy and Silver-Releasing Foam Dressings in the Management of Diabetic Ulcers

AbstractIntroduction Diabetic foot ulcers are one among the most commonly encountered complication of diabetes mellitus tackled by the surgical department worldwide. Negative pressure wound therapy (NPWT) and silver-releasing foam dressings are effective modalities for the treatment of ulcers. This study compares the two treatment modalities.Methods Sixty adult patients admitted with diabetic foot ulcers undergoing NPWT (vacuum-assisted closure [VAC]) or silver-releasing foam dressing (Biatain Ag) treatment were included in the study. Patients undergoing either of the treatment modalities were observed and followed up on a weekly basis prospectively. Wounds were routinely examined for the size of ulcer in area (cm2) and time taken for wound healing. Patients were also assessed qualitatively by means of a questionnaire to find out patient satisfaction and compliance.Results Time taken for wound healing among Biatain Ag group was found to be 24±9.483 days compared with only 19.73±7.575 days in the VAC group. Decrease in size ulcer measured in area was found to be 38.79% in Biatain Ag group, whereas in the VAC group it was found to be 26.56%. Patients were satisfied with both modalities of treatment; however, patient compliance was better for the Biatain Ag Group due to decrease in restriction of mobility and decrease in cost.Conclusion Overall, both modalities of treatment were found to be comparable and can be used with similar efficacy. It can be concluded that silver-releasing foam dressing can act as a beneficial alternative to NPWT in the treatment of diabetic ulcers.

Tropical grass and legume pastures may alter lamb meat physical and chemical characteristics.

The present study assessed the influence of the type of the tropical pastures on lamb body weight (BW) gain and meat quality. Fifty-four lambs were allocated to three grazing pastures: (1) AG - Aruana grass (Panicum maximum cv. IZ-5); (2) PP - pigeon pea legume (Cajanus cajan cv. Anão); and (3) CS - contiguous swards, half of the paddock with AG and half with PP. After 92days of grazing, the lambs were slaughtered. Carcasses were evaluated and the longissimus muscle was collected to determine color, lipid profile, tocopherol concentrations, and lipid oxidation. Although the pastures present differences in the characteristics of nutritional quality, the animals did not show difference in BW gain. The results show that all forage presented similar concentration of alpha-tocopherol (137 ± 14.37mgkg-1 of fresh matter), whereas total and condensed tannin contents were greater in PP, intermediate in CS, and the lowest in AG treatment (P = 0.0001). Meat α-tocopherol content was similar among treatments (P = 0.1392), with an average concentration close to the optimal level to reduce the meat oxidation. Meat from AG treatment had 45 and 25% lower n-6/n-3 ratio than meat from PP and CS treatments, respectively. The legume increases the unsaturated fatty acids and the grass can reduce the n6/n3 ratio. The level of condensed tannin concentration did show to have important effect on meat characteristics. Both tropical pastures studied can provide a high amount of alpha-tocopherol, generating a great potential to increase the concentration of this antioxidant in lamb's meat.