bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Antigen Retrieval Methods for Immunohistochemical Analysis of Cartilage Matrix Glycoproteins Using Cartilage Intermediate Layer Protein 2 (CILP-2) as an Example
Authors: Torga Taavi , Suutre Siim , Kisand Kalle , Aunapuu Marina , Arend Andres
Published: August 2024

The aim of this study was to compare different antigen retrieval methods to improve the outcome of immunohistochemistry (IHC) performed on osteoarthritic (OA) cartilage obtained from total knee replacement operation. A voluminous and dense extracellular matrix of articular cartilage inhibits antibody penetration, and therefore, proteins present at low concentrations and masked during fixation may need antigen retrieval to enhance an IHC outcome. We focused on the IHC detection of a minor but diagnostically promising cartilage glycoprotein, CILP-2 (cartilage intermediate layer protein 2), to demonstrate the effect of four different protocols: (1) heat-induced epitope retrieval (HIER), (2) proteolytic-induced epitope retrieval applying proteinase K and hyaluronidase (PIER), (3) HIER combined with PIER, and (4) no antigen retrieval (control). A semi-quantitative staining assessment based on the CILP-2 staining extent was applied. Out of the tested antigen retrieval protocols, the best CILP-2 IHC staining results were achieved by PIER. Combining PIER with HIER did not improve CILP-2 staining in the given experimental setting. Rather the opposite, the application of heat reduced the positive effect of PIER on CILP-2 staining and resulted in the frequent detachment of sections from the slides. Our findings emphasize the need for proper adaptation of antigen retrieval protocols for IHC to maximize the quantitative evaluation of minor matrix proteins in OA articular cartilage samples.
Workflow and Short-Term Functional Outcomes in Simultaneous Acute Code Stroke Activation and Stroke Reperfusion Therapy
Authors: Sarmiento Robert Joseph , Wagner Amanda , Sheriff Asif , Taralson Colleen , Moniz Nadine , Opsahl Jason , Jeerakathil Thomas , Buck Brian , Sevcik William , Shuaib Ashfaq , Kate Mahesh
Published: August 2024

The burden of simultaneous acute code stroke activation (ACSA) is not known. We aim to assess the effect of simultaneous ACSA on workflow metrics and home time at 90 days in patients undergoing reperfusion therapies in the emergency department. Simultaneous ACSA was defined as code activation within 60 min of the arrival of any patient receiving intravenous thrombolysis, within 150 min of the arrival of any patient receiving endovascular thrombectomy, within 45 min of the arrival of any patient receiving no reperfusion therapies (based on mean local door-to-needle and door-to-puncture times). Simultaneous ACSA was further graded as 1, 2 and 3. We assessed workflow metrics as door-to-CT (DTC) time, in minutes, and functional outcome as home time at 90 days. A total of 2605 patients were assessed as ACSA at a mean ± SD activations of 130.8 ± 17.1/month and 859 (33%) were simultaneous. Among all ACSA, 545 (20.9%) underwent acute reperfusion therapy with a mean age of 70.6 ± 14.2 years, 45.9% (n = 254) were female with a median (IQR) NIHSS of 13 (8–18). A total of 220 (40.4%) patients underwent simultaneous treatments. The median DTC time, in minutes, was prolonged in grade 3 simultaneous ACSA (18 (13, 28)) compared to non-simultaneous ACSA (15 (11, 21) β = 0.23, p < 0.0001). There was no difference in the median home time at 90 days between the simultaneous (58, 0–84.5 days) and non-simultaneous (54, 0–85 days) patients. Simultaneous ACSA is frequent in patients receiving acute reperfusion therapies. An optimal workflow in high-volume centers may help mitigate the clinical and system burden associated with simultaneity.
An Electrolytic Elemental Iron Powder Effectively Regenerates Hemoglobin in Anemic Rats and Is Relatively Well Absorbed When Compared to Ferrous Sulfate Monohydrate
Authors: Swain James H. , Glosser Logan D. , Jang Caroline J. , Nemeth Ryan C. , Bethi Anshul R. , Zheng Eva L. , Boron Evelyn R. , Fox Hannah M.
Published: August 2024

Elemental iron powders are used as food fortificants to reduce the incidence of iron deficiency anemia. However, many commercially available iron powders are relatively untested in vivo. The purpose of this study was to determine the hemoglobin regeneration efficiency (HRE) and relative iron bioavailability (RBV) of an electrolytic elemental iron powder (EIP), by treating anemic rats with 14 d iron repletion diets fortified with four different concentrations (12, 24, 36, or 48 mg iron/kg diet) of EIP and bakery-grade ferrous sulfate monohydrate (FS; FeSO4•H2O), or no added iron (control); n = 9–12/group. The HRE of FS was significantly higher (p ≤ 0.05) than EIP at each concentration of dietary iron tested. For EIP, the HREs (ratios) of diets containing 12, 24, 36, and 48 mg iron/kg were 0.356, 0.205, 0.197, and 0.163, respectively. For both EIP and FS, HRE was inversely associated with increasing dietary iron. The RBVs (%) of iron from EIP in diets at 12, 24, 36, and 48 mg iron/kg as compared to FS were 64.5, 59.1, 50.6, and 54.3%, respectively. Overall, findings show that at the concentrations of iron tested, EIP has RBVs greater than 50% and is an effective fortification agent to replenish hemoglobin and correct iron deficiency anemia.
A Dietary Intervention in Adults with Overweight or Obesity Leads to Weight Loss Irrespective of Macronutrient Composition
Authors: Kafyra Maria , Kalafati Ioanna Panagiota , Stefanou Garyfallia , Kourlaba Georgia , Moulos Panagiotis , Varlamis Iraklis , Kaliora Andriana C. , Dedoussis George V.
Published: August 2024

Obesity is a critical public health issue, necessitating effective weight loss interventions. While various dietary regimens have been explored, individual responses to interventions often vary. This study involved a 3-month dietary intervention aiming at assessing the role of macronutrient composition and the potential role of genetic predisposition in weight loss among Greek adults. This randomized clinical trial followed the CONSORT principles, recruiting 202 participants overall; 94 received a hypocaloric, high-protein diet and 108 received a high-carbohydrate, hypocaloric diet. Genetic predispositions were assessed through 10 target variants known for their BMI associations. Participants’ weight and BMI values were recorded at baseline and post-intervention (n = 202 at baseline, n = 84 post-intervention) and an imputation method was applied to account for the observed missing values. Participants experienced a statistically significant weight loss across all dietary regimens (p < 0.001). Genetic analyses did not display statistically significant effects on weight loss. No significant differences in weight loss were observed between macronutrient groups, aligning with the POUNDS Lost and DIETFITS studies. This study underscores the importance of dietary interventions for weight loss and the potential contributions of genetic makeup. These findings contribute to obesity management within the Greek population and support the need for further research in personalized interventions.
Dietary Choline Intake Is Beneficial for Cognitive Function and Delays Cognitive Decline: A 22-Year Large-Scale Prospective Cohort Study from China Health and Nutrition Survey
Authors: Huang Feifei , Guan Fangxu , Jia Xiaofang , Zhang Jiguo , Su Chang , Du Wenwen , Ouyang Yifei , Li Li , Bai Jing , Zhang Xiaofan , Wei Yanli , Zhang Bing , He Yuna , Wang Huijun
Published: August 2024

Pre-clinical studies have discovered the neuroprotective function and the benefit for cognitive function of choline. However, it remains unclear whether these benefits observed in animal studies also work in humans. The aims of this study are to examine the effects of dietary choline intake on cognitive function and cognitive decline during ageing in middle-aged and elderly Chinese. We included 1887 subjects aged 55~79 years with 6696 observations from the China Health and Nutrition Survey cohort study. The subjects were followed up for 6 to 21 years, with an average of 12.2 years. A dietary survey was conducted over 3 consecutive days with a 24 h recall, using household weight-recording methods. Based on the China Food Composition, data from USDA, and published literature, the dietary choline intake was calculated as the sum of free choline, phosphocholine, phosphatidylcholine, sphingomyelin, and glycerophosphocholine. Cognitive function was assessed using a subset of the Telephone Interview for Cognitive Status-modified (TICS-m) items. In order to eliminate the different weight of scores in each domain, the scores were converted by dividing by the maximum score in each domain, which ranged from 0 to 3 points. Higher cognitive scores represented better cognition. We used two-level mixed effect models to estimate the effects of dietary choline intake on cognitive score and cognitive decline rate in males and females, respectively. The average dietary choline intake was 161.1 mg/d for the baseline. After adjusting for confounders, the dietary choline intake was significantly associated with higher cognitive score in both males and females. The cognitive score in the highest quartile group of dietary choline was 0.085 for males and 0.077 for females–higher than those in the lowest quartile group (p < 0.01 for males, p < 0.05 for females). For every 10-year increase in age, the cognitive score decreased by 0.266 for males and 0.283 for females. The cognitive score decline rate of the third quartile group of dietary choline was 0.125/10 years lower than that of the lowest quartile group in females (p < 0.05). Dietary choline intake not only improves cognitive function, but also postpones cognitive decline during the aging process. The findings of this study highlight the neuroprotective benefit of choline in the middle-aged and elderly Chinese population, especially among females.
Okinawa-Based Nordic Diet Decreases Plasma Glial Fibrillary Acidic Protein Levels in Type 2 Diabetes Patients
Authors: Pocevičiūtė Dovilė , Wennström Malin , Ohlsson Bodil
Published: August 2024

Elevated levels of glial fibrillary acidic protein (GFAP) in plasma reflect neuroinflammation and are linked to cognitive decline. Preclinical studies show that dietary change can attenuate astrocyte reactivity and neuroinflammation. In the current study, we investigate if the Okinawa-based Nordic (O-BN) diet alters plasma GFAP levels in patients with Type 2 Diabetes (T2D), a metabolic disorder associated with cognitive disturbances and an increased risk of dementia. Plasma GFAP levels were measured in T2D patients (n = 30) at baseline, after 3 months of the diet, and after a subsequent 4 months of unrestricted diets. The GFAP levels decreased significantly after 3 months of the diet (p = 0.048) but reverted to baseline levels after 4 months of unrestricted diets. At baseline, the GFAP levels correlated significantly with levels of the neurodegeneration marker neurofilament light polypeptide (r = 0.400*) and, after correcting for age, sex, and body mass index, with proinflammatory plasma cytokines (ranging from r = 0.440* to r = 0.530**) and the metabolic hormone islet amyloid polypeptide (r = 0.478*). We found no correlation with psychological well-being. These results suggest that the O-BN diet reduces neuroinflammation in T2D patients and may thus be an important preventive measure for managing T2D and reducing the risk of neurodegenerative disorders.
Targeting the Hippo- Yes-Associated Protein/Transcriptional Coactivator with PDZ-Binding Motif Signaling Pathway in Primary Liver Cancer Therapy
Authors: Wang Yina , Rui Liangyou
Published: August 2024

Liver cancer imposes a pervasive global health challenge, ranking among the most prevalent cancers worldwide. Its prevalence and mortality rates are on a concerning upward trajectory and exacerbated by the dearth of efficacious treatment options. The Hippo signaling pathway, originally discovered in Drosophila, comprises the following four core components: MST1/2, WW45, MOB1A/B, and LATS1/2. This pathway regulates the cellular localization of the transcriptional coactivator Yes-associated protein/transcriptional coactivator with PDZ-binding motif (YAP/TAZ) through a series of enzymatic reactions. The Hippo-YAP/TAZ pathway maintains a balance between cell proliferation and apoptosis, regulates tissue and organ sizes, and stabilizes the internal environment. Abnormalities of any genes within the Hippo signaling pathway, such as deletion or mutation, disturb the delicate balance between cell proliferation and apoptosis, creating a favorable condition for tumor initiation and progression. Mutations or epigenetic alterations in the Hippo signaling pathway components can lead to its inactivation. Consequently, YAP/TAZ becomes overexpressed and activated, promoting excessive cell proliferation and inhibiting apoptosis. This dysregulation is closely associated with the development of liver cancer. This review discusses the pivotal role of the Hippo signaling pathway in the pathogenesis and progression of liver cancer. By elucidating its mechanisms, we aim to offer new insights into potential therapeutic targets for effectively combating liver cancer.
Electric Control of the In-Plane Deflection of Laser Beam Pairs within a Photonic Slab Waveguide
Authors: Henkel Andreas , Knoth Christopher , Buchmüller Maximilian , Görrn Patrick
Published: August 2024

A symmetric laser beam pair can provide unique control over light–matter interactions. When propagating within a symmetric slab waveguide, its non-conical diffraction at a specially designed symmetric leaky waveguide grating can be completely suppressed, a phenomenon we term zero diffraction. This allows for infinite contrast control of light detrapping from the slab waveguide. In this paper, we demonstrate the electric control of the local deflection of a beam pair while preserving its properties. This introduces a novel method for routing optical signals across a planar waveguide. We utilize a waveguide structure that enables zero diffraction under non-conical incidence on a 1D grating and design a grating geometry capable of deflecting the beam pair by approximately 90 degrees. This design is experimentally realized using three different diffractive elements for trapping, deflection, and detrapping. The deflection is controlled by an electric field, allowing the deflected intensity to be tuned by a factor of 21.
A Method to Study Migration and Invasion of Mouse Intestinal Organoids
Authors: Wouters Valérie M. , Longobardi Ciro , Medema Jan Paul
Published: August 2024

Colorectal cancer (CRC) is the third most common cancer worldwide and it is the second leading cause of cancer death. In CRC, as in most cancers, the formation of metastasis through the migration and invasion of cancer cells to distant organs is associated with a dismal prognosis. The study of the mechanisms associated with cancer, and, in particular, CRC, changed in the last decade due to the introduction of organoids. These represent a step forward in terms of complexity from cell lines and allowed the use of mouse models in cancer research to be limited. Although organoids faithfully model the cellular complexity of CRC, current protocols do not allow for the use of organoids in some crucial processes of metastasis, such as migration and invasion. In this study, a method to study migration and invasion using mouse intestinal organoids in vitro is presented. This protocol provides researchers with the opportunity to investigate the migratory behavior of organoid lines and study the impact of distinct mutations on the migratory and invasive capacity of cancer cells.
Advancement in the Antigenic Epitopes and Vaccine Adjuvants of African Swine Fever Virus
Authors: Wu Qiong , Li Chang , Zhu Bo , Zhu Jiajia , Yang Keli , Liu Zewen , Liu Wei , Gao Ting , Yuan Fangyan , Guo Rui , Tian Yongxiang , Zhou Danna
Published: August 2024

African swine fever virus (ASFV), a highly virulent double-stranded DNA virus, poses a significant threat to global pig farming, with mortality rates in domestic pigs reaching up to 100%. Originating in Kenya in 1921, ASFV has since proliferated to Western Europe, Latin America, Eastern Europe, and most recently China in 2018, resulting in substantial global agricultural losses. Antigenic epitopes, recognized by the immune system’s T cells and B cells, are pivotal in antiviral immune responses. The identification and characterization of these antigenic epitopes can offer invaluable insights into the immune response against ASFV and aid in the development of innovative immunotherapeutic strategies. Vaccine adjuvants, substances that amplify the body’s specific immune response to antigens, also play a crucial role. This review provides an overview of the progress in studying T/B-cell epitopes in ASFV proteins and ASFV vaccine adjuvants, highlighting their role in the immune response and potential use in new vaccine development.
S. mutans Antisense vicK RNA Over-Expression Plus Antibacterial Dimethylaminohexadecyl Methacrylate Suppresses Oral Biofilms and Protects Enamel Hardness in Extracted Human Teeth
Authors: Yu Shuang , Xu Mengmeng , Wang Zheng , Deng Yang , Xu Hockin H. K. , Weir Michael D. , Homayounfar Negar , Fay Guadalupe Garcia , Chen Hong , Yang Deqin
Published: August 2024

Streptococcus mutans (S. mutans) antisense vicK RNA (ASvicK) is a non-coding RNA that regulates cariogenic virulence and metabolic activity. Dimethylaminohexadecyl methacrylate (DMAHDM), a quaternary ammonium methacrylate used in dental materials, has strong antibacterial activity. This study examined the effects of S. mutans ASvicK on DMAHDM susceptibility and their combined impact on inhibiting S. mutans biofilm formation and protecting enamel hardness. The parent S. mutans UA159 and ASvicK overexpressing S. mutans (ASvicK) were tested. The minimum inhibitory concentration (MIC) and minimum bactericidal concentrations for planktonic bacteria (MBC-P) and biofilms (MBC-B) were measured. As the ASvicK MBC-B was 175 μg/mL, live/dead staining, metabolic activity (MTT), colony-forming units (CFUs), biofilm biomass, polysaccharide, and lactic acid production were investigated at 175 μg/mL and 87.5 μg/mL. The MIC, MBC-P, and MBC-B values for DMAHDM for the ASvicK strain were half those of the UA159 strain. In addition, combining S. mutans ASvicK with DMAHDM resulted in a significant 4-log CFU reduction (p < 0.05), with notable decreases in polysaccharide levels and lactic acid production. In the in vitro cariogenic model, the combination achieved the highest enamel hardness at 67.1% of sound enamel, while UA159 without DMAHDM had the lowest at 16.4% (p < 0.05). Thus, S. mutans ASvicK enhanced DMAHDM susceptibility, and their combination effectively inhibited biofilm formation and minimized enamel demineralization. The S. mutans ASvicK + DMAHDM combination shows great potential for anti-caries dental applications.
Quality Control of Microscopic Diagnosis of Malaria in Healthcare Facilities and Submicroscopic Infections in Mossendjo, the Department of Niari, the Republic of the Congo
Authors: Fila-Fila Grâce Petula Urielle , Koukouikila-Koussounda Felix , Niama Fabien Roch , Bissombolo Madingou Lauriate Prudencie , Demboux Jordy Exaucé , Mandiangou Aldi Fred , Vembe Mahounga Stéphane , Doniama Ahmed Jordy , Dossou-Yovo Louis Régis , Casimiro Prisca Nadine , Issamou Mayengue Pembe
Published: August 2024

The control and management of malaria are linked to the quality of diagnosis. We sought to estimate the performance of routine microscopy for malaria diagnosis and assess the prevalence of submicroscopic Plasmodium (P.) falciparum infection among febrile patients in two healthcare facilities in Mossendjo, the Republic of the Congo. A cross-sectional study was conducted between January and December 2022. A total of 650 and 234 patients with signs of uncomplicated malaria were enrolled at the Centre de Sante Intégré (CSIMSJ) and Hôpital de Base (HBMSJ), respectively. Two thick blood smears were performed for each patient, one analyzed by routine microscopists and the other by an expert. The msp-1 and msp-2 genes were genotyped to detect submicroscopic P. falciparum infection. At the CSIMSJ, the sensitivity was 49.5% and the specificity was 88.6%. The positive and negative predictive values were 77.7% and 68.7%, respectively. At the HBMSJ, the sensitivity was 32.9% and the specificity was 79.4%. The positive and negative predictive values were 44.8% and 69.5%, respectively. P. falciparum was the only species detected by routine microscopists, while experts identified some cases with P. malariae and P. ovale. The proportion of submicroscopic infections was 35.75%. Children under 5 years old had higher rates of parasitemia. However, submicroscopic infections were more pronounced in the adult group. The performance of routine malaria microscopists at Mossendjo was inaccurate at both sites. With the large proportion of submicroscopic infection, malaria management at Mossendjo requires the improvement of microscopists’ skills and the concomitant use of RDTs.
One Health Priorities: Advancing Veterinary Public Health in Latin America and the Caribbean
Authors: Rocha Felipe , Sibim Alessandra Cristiane , Molina-Flores Baldomero , Chiba de Castro Wagner Antonio , Kmetiuk Louise Bach , Alves Renato Vieira , dos Santos André Luis de Sousa , Moreno Margarita Corrales , Faccini-Martínez Álvaro A. , Cediel Natalia Margarita , Biondo Alexander Welker , Cosivi Ottorino , Vigilato Marco Antonio Natal
Published: August 2024

One Health (OH) is an integrative approach to human, animal, and environmental health and can be used as a comprehensive indicator for comparative purposes. Although an OH index has been proposed for comparing cities, states, and countries, to date, no practical study has compared countries using this approach. Accordingly, this study aimed to assess OH initiatives using a survey with a veterinary public health focus. The questionnaire contained 104 quantitative questions and was sent to representatives of governmental institutions of 32 countries in the Americas. After exclusion criteria were considered, a total of 35 questionnaires from 17 countries were analyzed, with country names remaining undisclosed during the statistical analyses to protect potentially sensitive information. Principal component analysis (PCA) of health parameters in Latin America and the Caribbean (LAC) as a function of country perception (self-vector) showed that food safety was ranked higher than public policies (p = 0.009), and that both (p = 0.003) were ranked higher than institutional routines related to zoonosis programs. National policies in accordance with international standards, regulations, recommendations, and guidelines was considered the standout topic for public policy, with higher-ranking topics including standard. Meanwhile, challenging topics included tools, preparedness, governance, and research. Food safety showed both strengths and challenges in the coordination of its activities with other sectors. Food safety communication was scored as a strength, while foodborne diseases prevention was ranked as a challenge. Institutional routines for zoonosis maintained both strong and challenging topics in the execution and implementation of attributions and daily routine. Thus, the survey showed that topics such as access to and compliance with international guidelines and intercountry integration were ranked higher than in-country articulation, particularly among food safety, zoonoses, and environmental institutions.
Computational Design and Optimization of Peptide Inhibitors for SIRT2
Authors: Alkhatabi Heba A. , Naemi Fatmah M. A. , Alsolami Reem , Alatyb Hisham N.
Published: August 2024

Sirtuin 2 (SIRT2), an NAD+-dependent deacetylase, is crucial for regulating vital physiological processes, including aging, DNA repair, and cell cycle progression. Its abnormal activity is linked to diseases such as Parkinson’s disease, cancer, and metabolic disorders, making it a potential target for therapeutic intervention. While small molecule inhibitors have been studied, peptide-based inhibitors offer a promising alternative due to their selectivity and bioavailability. This study explores the effects of converting the naturally occurring cyclic inhibitor peptide of SIRT2 (S2iL5) into a non-cyclic form by replacing a residue with FAK (LYS + CF3CO−). The new peptide sequence, Tyr-His-Thr-Tyr-His-Val-FAK (LYS)-Arg-Arg-Thr-Asn-Tyr-Tyr-Cys, was modeled to confirm its stable conformation. Docking studies and MM/GBSA calculations showed that the non-cyclic peptide had a better binding free energy (−50.66 kcal/mol) compared to the cyclic S2iL5 (−49.44 kcal/mol). Further mutations generated 160,000 unique peptides, screened using a machine learning-based QSAR model. Three promising peptides (Peptide 1: YGGNNVKRRTNYYC, Peptide 2: YMGEWVKRRTNYYC, and Peptide 3: YGGNGVKRRTNYYC) were selected and further modeled. Molecular dynamics (MD) analyses demonstrated that Peptide 1 and Peptide 2 had significant potential as SIRT2 inhibitors, showing moderate stability and some structural flexibility. Their best binding free energies were −59.07 kcal/mol and −46.01 kcal/mol, respectively. The study aimed to enhance peptide flexibility and binding affinity, suggesting that optimized peptide-based inhibitors can interact effectively with SIRT2. However, further experimental validation is necessary to confirm these computational predictions and evaluate the therapeutic potential of the identified peptides.
Production and Antibacterial Activity of Atypical Siderophore from Pseudomonas sp. QCS59 Recovered from Harpachene schimperi
Authors: Almuhawish Mashael A. , Kotb Essam , Alkhaldi Eida , Ahmed Asmaa A.
Published: August 2024

Among sixty-eight pseudomonads, isolate QCS59 from the rhizosphere of H. schimperi was selected based on its siderophore level. Production was optimal in Kings B supplemented with 2% peptone and 0.5% fructose at pH 6.5 and 25 °C for 72 h. Additionally, the threshold potential of iron was found at a concentration of 10 µM. After purification, the acidified siderophore presented a maximum absorption peak of 360 nm, while the neutral form presented a maximum of 414 nm, confirming its pyoverdine (PVD) nature. Furthermore, a major peak appeared at a retention time (RT) of 27.5 min during RP-HPLC, confirming its homogeneity. Interestingly, it demonstrated effective antibacterial activity, especially against Escherichia coli ATCC 8739, with a minimum inhibitory concentration (MIC) of 6.3 µg/mL and a minimum bactericidal concentration (MBC) of 12.5 µg/mL. At ½ the MIC value, it inhibited 82.1% of well-established biofilms of Salmonella enterica. There was an increase in malondialdehyde (MDA) and antioxidative enzymes, especially catalase (CAT) in the treated bacteria because of the peroxidation of membrane lipids and oxidative stress, respectively. SEM proved cellular lysis and surface malformation in most of the treated bacteria. This study concludes that QCS59 siderophore is a promising antibacterial candidate for treating wastewater bacteria and skin pathogens.
Synthesis, Characterization, and Biological Evaluation of Chitosan Nanoparticles Cross-Linked with Phytic Acid and Loaded with Colistin against Extensively Drug-Resistant Bacteria
Authors: Pacheco Fabian , Barrera Alejandro , Ciro Yhors , Polo-Cerón Dorian , Salamanca Constain H. , Oñate-Garzón José
Published: August 2024

The natural evolution of microorganisms, as well as the inappropriate use of medicines, have accelerated the problem of drug resistance to many of the antibiotics employed today. Colistin, a lipopeptide antibiotic used as a last resort against multi-resistant strains, has also begun to present these challenges. Therefore, this study was focused on establishing whether colistin associated with chitosan nanoparticles could improve its antibiotic activity on an extremely resistant clinical isolate of Pseudomonas aeruginosa, which is a clinically relevant Gram-negative bacterium. For this aim, nanoparticulate systems based on phytic acid cross-linked chitosan and loaded with colistin were prepared by the ionic gelation method. The characterization included particle size, polydispersity index-PDI, and zeta potential measurements, as well as thermal (DSC) and spectrophotometric (FTIR) analysis. Encapsulation efficiency was assessed by the bicinchoninic acid (BCA) method, while the antimicrobial evaluation was made following the CLSI guidelines. The results showed that colistin-loaded nanoparticles were monodispersed (PDI = 0.196) with a particle size of around 266 nm and a positive zeta potential (+33.5 mV), and were able to associate with around 65.8% of colistin and decrease the minimum inhibitory concentration from 16 μg/mL to 4 μg/mL. These results suggest that the association of antibiotics with nanostructured systems could be an interesting alternative to recover the antimicrobial activity on resistant strains.
Exploring the Diversity and Dehydration Performance of New Mixed Tutton Salts (K2V1−xM’x(SO4)2(H2O)6, Where M’ = Co, Ni, Cu, and Zn) as Thermochemical Heat Storage Materials
Authors: Oliveira Neto João G. de , Marques Jacivan V. , Santos Jayson C. dos , Santos Adenilson O. dos , Lang Rossano
Published: August 2024

Tutton salts form an isomorphic crystallographic family that has been intensively investigated in recent decades due to their attractive thermal and optical properties. In this work, we report four mixed Tutton crystals (obtained by the slow solvent evaporation method) with novel chemical compositions based on K2V1−xM’x(SO4)2(H2O)6, where M’ represents Co, Ni, Cu, and Zn, aiming at thermochemical energy storage applications. Their structural and thermal properties were correlated with theoretical studies. The crystal structures were solved by powder X-ray diffraction using the Rietveld method with similar compounds. All of the samples crystallized in monoclinic symmetry with the P21/a-space group. A detailed study of the intermolecular interactions based on Hirshfeld surfaces and 2D fingerprint mappings showed that the main interactions arise from hydrogen bonds (H∙∙∙O/O∙∙∙H) and dipole–ion (K∙∙∙O/O∙∙∙K). On the other hand, free space percentages in the unit cells determined by electron density isosurfaces presented low values ranging from 0.53 (V–Ni) to 0.81% (V–Cu). The thermochemical findings from thermogravimetry, a differential thermal analysis, and differential scanning calorimetry indicate that K2V0.47Ni0.53(SO4)2(H2O)6 salt is the most promising among mixed salts (K2V1−xM’x(SO4)2(H2O)6) for heat storage potential, achieving a low dehydration temperature (≈85 °C), high dehydration enthalpy (≈360 kJ/mol), and high energy storage density (≈1.84 GJ/m3).
Rapid Reduction of Phytotoxicity in Green Waste for Use as Peat Substitute: Optimization of Ammonium Incubation Process
Authors: Cui Wenzhong , Liu Juncheng , Bai Qi , Wu Lingyi , Qi Zhiyong , Zhou Wanlai
Published: August 2024

The rapid growth of the horticultural industry has increased demand for soilless cultivation substrates. Peat, valued for its physical and chemical properties, is widely used in soilless cultivation. However, peat is non-renewable, and over-extraction poses serious ecological risks. Therefore, sustainable alternatives are urgently needed. Ammonium incubation, a novel method to reduce phytotoxicity, offers the potential for green waste, a significant organic solid waste resource, to substitute peat. This study optimized the ammonium incubation process to reduce green waste phytotoxicity. It systematically examined different nitrogen salts (type and amount) and environmental conditions (temperature, aeration, duration) affecting detoxification efficiency. Results show a significant reduction in phytotoxicity with ammonium bicarbonate, carbonate, and sulfate, especially carbonate, at 1.5%. Optimal conditions were 30 °C for 5 days with regular aeration. Under these conditions, ammonium salt-treated green waste significantly reduced total phenolic content and stabilized germination index (GI) at a non-phytotoxic level (127%). Using treated green waste as a partial peat substitute in lettuce cultivation showed promising results. This low-cost, low-energy method effectively converts green waste into sustainable peat alternatives, promoting eco-friendly horticulture and environmental conservation.
Effect of CO2 Elevation on Tomato Gas Exchange, Root Morphology and Water Use Efficiency under Two N-Fertigation Levels
Authors: Zhang Manyi , Zhao Wentong , Liu Chunshuo , Xu Changtong , Wei Guiyu , Cui Bingjing , Hou Jingxiang , Wan Heng , Chen Yiting , Zhang Jiarui , Wei Zhenhua
Published: August 2024

Atmospheric elevated CO2 concentration (e[CO2]) decreases plant nitrogen (N) concentration while increasing water use efficiency (WUE), fertigation increases crop nutrition and WUE in crop; yet the interactive effects of e[CO2] coupled with two N-fertigation levels during deficit irrigation on plant gas exchange, root morphology and WUE remain largely elusive. The objective of this study was to explore the physiological and growth responses of ambient [CO2] (a[CO2], 400 ppm) and e[CO2] (800 ppm) tomato plant exposed to two N-fertigation regimes: (1) full irrigation during N-fertigation (FIN); (2) deficit irrigation during N-fertigation (DIN) under two N fertilizer levels (reduced N (N1, 0.5 g pot−1) and adequate N (N2, 1.0 g pot−1). The results indicated that e[CO2] associated with DIN regime induced the lower N2 plant water use (7.28 L plant−1), maintained leaf water potential (−5.07 MPa) and hydraulic conductivity (0.49 mol m−2 s−1 MPa−1), greater tomato growth in terms of leaf area (7152.75 cm2), specific leaf area (223.61 cm2 g−1), stem and total dry matter (19.54 g and 55.48 g). Specific root length and specific root surface area were increased under N1 fertilization, and root tissue density was promoted in both e[CO2] and DIN environments. Moreover, a smaller and denser leaf stomata (4.96 µm2 and 5.37 mm−2) of N1 plant was obtained at e[CO2] integrated with DIN strategy. Meanwhile, this combination would simultaneously reduce stomatal conductance (0.13 mol m−2 s−1) and transpiration rate (1.91 mmol m−2 s−1), enhance leaf ABA concentration (133.05 ng g−1 FW), contributing to an improvement in WUE from stomatal to whole-plant scale under each N level, especially for applying N1 fertilization (125.95 µmol mol−1, 8.41 µmol mmol−1 and 7.15 g L−1). These findings provide valuable information to optimize water and nitrogen fertilizer management and improve plant water use efficiency, responding to the potential resource-limited and CO2-enriched scenario.
Long-Term Monitored Norway Spruce Plots in the Ore Mountains—30 Years of Changes in Forest Health, Soil Chemistry and Tree Nutrition after Air Pollution Calamity
Authors: Novotný Radek , Fadrhonsová Věra , Šrámek Vít
Published: August 2024

The Ore Mountains were historically one of the most polluted areas in Europe, where high sulphur dioxide concentrations and a high level of atmospheric deposition led to a vast decline in Norway spruce stands in the mountain ridge plateau. In this article, we evaluate the trends in the atmospheric deposition load, soil chemistry, tree nutrition, crown defoliation and height increment in a network of twenty research plots monitored for last thirty years in this region. The decrease in sulphur and nitrogen deposition was most pronounced at the end of 1990s. Extreme values of sulphur deposition (100–200 kg.ha−1.year−1) were recorded in throughfall under mature Norway spruce stands in the late 1970s, and after felling of the damaged stand, the deposition levels were comparable to open plot bulk deposition. Nitrogen deposition decreased more slowly compared with sulphur, and a decrease in base cation deposition was observed concurrently. The current deposition load is low and fully comparable to other mountain areas in central Europe. Accordingly, the health of young spruce stands, as assessed by defoliation and height increment, has improved and now corresponds to the Czech national average. On the other hand, no significant changes were observed in the soil chemistry, even though some of the plots were limed. Acidic or strongly acidic soil prevails, often with a deficiency of exchangeable calcium and magnesium in the mineral topsoil, as well as decreases in available phosphorus. This is reflected in the foliage chemistry, where we see an imbalance between a relatively high content of nitrogen and decreasing contents of phosphorus, potassium and calcium. Despite the observed positive trends in air quality and forest health, the nutritional imbalance on acidified soils poses a risk for the future of forest stands in the region.
Effect of Graphene Oxide Nanoparticles Incorporation on the Mechanical Properties of a Resin-Modified Glass Ionomer Cement
Authors: Moreira e Moraes Rafael Ubaldo , Abreu Marcos Andre Pinheiro , Frazão Mayara Cristina Abas , Ferreira Paulo Vitor Campos , Bauer José , Carvalho Ceci Nunes , Carvalho Edilausson Moreno
Published: August 2024

The objective of this study was to evaluate the effect of incorporating different concentrations of graphene oxide (GO) nanoparticles on the mechanical properties of a resin-modified glass ionomer cement (RMGIC). A commercial RMGIC (Resiglass R, Biodinâmica) was modified by incorporating 0.1% and 0.5% (by weight) of GO into the powder’s material. An unmodified RMGIC was used as a control group. Powder samples were characterized using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Specimens were fabricated and subjected to flexural strength (n = 15), modulus of elasticity (n = 15), Vicker’s microhardness (n = 10), and surface roughness tests (n = 10). Data were analyzed using one-way ANOVA and Tukey’s post hoc test (α = 5%). Experimental groups’ powder demonstrated a homogeneous dispersion of GO. No statistically significant difference was observed in flexural strength (p = 0.067) and modulus of elasticity (p = 0.143) tests. The groups containing 0.1% and 0.5% GO showed significantly higher microhardness and lower surface roughness values (p < 0.001) compared to the control group. The incorporation of GO nanoparticles at concentrations of 0.1% and 0.5% improved the microhardness and surface roughness without negatively affecting the flexural strength and modulus of elasticity of an RMGIC.
Advancements in Gellan Gum-Based Films and Coatings for Active and Intelligent Packaging
Authors: Li Hang , Gao Kun , Guo Huan , Li Rongfeng , Li Guantian
Published: August 2024

Gellan gum (GG) is a natural polysaccharide with a wide range of industrial applications. This review aims to investigate the potential of GG-based films and coatings to act as environmentally friendly substitutes for traditional petrochemical plastics in food packaging. GG-based films and coatings exhibit versatile properties that can be tailored through the incorporation of various substances, such as plant extracts, microorganisms, and nanoparticles. These functional additives enhance properties like the light barrier, antioxidant activity, and antimicrobial capabilities, all of which are essential for extending the shelf-life of perishable food items. The ability to control the release of active compounds, along with the adaptability of GG-based films and coatings to different food products, highlights their effectiveness in preserving quality and inhibiting microbial growth. Furthermore, GG-based composites that incorporate natural pigments can serve as visual indicators for monitoring food freshness. Overall, GG-based composites present a promising avenue for the development of sustainable and innovative food packaging solutions.
Tuning the Properties of Xylan/Chitosan-Based Films by Temperature and Citric Acid Crosslinking Agent
Authors: Camaño Erhardt Martina , Solier Yamil Nahún , Inalbon María Cristina , Mocchiutti Paulina
Published: August 2024

Petroleum-based food packaging causes environmental problems such as waste accumulation and microplastic generation. In this work, biobased films from stable polyelectrolyte complex suspensions (PECs) of xylan and chitosan (70 Xyl/30 Ch wt% mass ratio), at different concentrations of citric acid (CA) (0, 2.5, 5, 7.5 wt%), were prepared and characterized. Films were treated at two temperatures (135 °C, 155 °C) and times (30 min, 60 min) to promote covalent crosslinking. Esterification and amidation reactions were confirmed by Fourier Transform Infrared Spectroscopy and Confocal Raman Microscopy. Water resistance and dry and wet stress–strain results were markedly increased by thermal treatment, mainly at 155 °C. The presence of 5 wt% CA tended to increase dry and wet stress–strain values further, up to 88 MPa—10% (155 °C for 60 min), and 5.6 MPa—40% (155 °C for 30 min), respectively. The UV-blocking performance of the films was improved by all treatments, as was thermal stability (up to Tonset: 230 °C). Contact angle values were between 73 and 84°, indicating partly wettable surfaces. Thus, thermal treatment at low CA concentrations represents a good alternative for improving the performance of Xyl/Ch films.
Correlation of Dielectric Properties and Vibrational Spectra of Composite PVDF/Salt Fibers
Authors: Dallaev Rashid , Sarkar Ranjini , Selimov Daud , Papež Nikola , Kočková Pavla , Schubert Richard , Častková Klara , Orudzhev Farid , Ramazanov Shikhgasan , Holcman Vladimír
Published: August 2024

Nitride salts were added to polyvinylidene fluoride fibers and then the fiber mats were prepared by electrospinning. An experimental investigation of the structure was provided by Raman, FTIR, SEM, and XRD. The phase ratio of the polymer was studied both theoretically and experimentally in connection with the addition of the hydrates Mg(NO3)2, Ca(NO3)2, and Zn(NO3)2 salts. The comparison of simulated and experimental data for vibrational spectroscopies is discussed. We provide a comparison of triboelectric, dielectric, and compositional characterization of PVDF fibers doped with three types of nitride hydrates. Doping of PVDF fibers with magnesium nitrate hexahydrate leads to significant improvement of the triboelectric performance.
Role of Minor Phase Morphology on Mechanical and Shape-Memory Properties of Polylactide/Bio-Polyamide Nanocomposite
Authors: Bondarenko Vladislav , Hosseinnezhad Ramin , Voznyak Andrei
Published: August 2024

In situ-generated nanofibrillar polymer–polymer composites are excellent candidates for the production of polymer materials, with high mechanical and SME properties. Their special feature is the high degree of dispersion of the in situ-generated nanofibers and the ability to form entangled nanofiber structures with high aspect ratios through an end-to-end coalescence process, which makes it possible to effectively reinforce the polymer matrix and, in many cases, increase its ductility. The substantial interfacial area, created by the in situ formed fiber/matrix morphology, significantly strengthens the interfacial interactions, which are crucial for shape fixation and shape recovery. Using the polylactide/bio-polyamide (PLA/PA) system as an example, it is shown that in situ PA fibrillation improves the mechanical and shape-memory properties of PLA. The modulus of elasticity increases by a factor of 1.4, the elongation at break increases by a factor of 30, and the shape-strain/fixity ratio and shape recovery increase from 80.2 to 97.4% and from 15.5 to 94.0%, respectively. The morphology of the minor PA phase is crucial. The best result is achieved when a physically entangled nanofibrous network is formed.
Metabolizable Energy Value of Fat and Meals Obtained from Black Soldier Fly Larvae (Hermetia illucens) for Broiler Chickens
Authors: Chobanova Sashka , Karkelanov Nikolay , Mansbridge Stephen Charles , Whiting Isobel Margaret , Tukša Marko , Rose Stephen Paul , Pirgozliev Vasil Radoslavov
Published: August 2024

An experiment was conducted to determine the apparent metabolizable energy (AME) and nitrogen-corrected AME (AMEn) of defatted black soldier fly larvae meal (BSM), full-fat dry larvae meal (BSL), and larvae fat (LF) for broiler chickens. The BSM, BSL, and LF contained on a g/kg basis, respectively, crude protein, 459, 399, 0; crude fat, 171, 240, 923; dry matter, 963, 940, 997; neutral detergent fiber, 210, 333, 0; acid detergent fibers, 95, 93, 0; and gross energy (MJ/kg), 22.04, 22.78, 38.16. An AME bioassay was performed wherein broilers were fed four experimental diets (a maize–wheat–soy basal diet and three test diets containing 100 g/kg BSM, BSL, or LF, respectively). The AME of BSM, BSL, and LF was calculated based on the differences between the AME values of basal and test diets (substitution method). The AME and AMEn for BSM, BSL, and LF were determined to be 18.20 and 17.40; 17.60 and 16.50; and 36.50 and 35.60 MJ/kg DM, respectively. There were no significant differences (p > 0.05) between nutrient retention coefficients of dry matter, N, and fat. The results showed that the examined products from black soldier fly larvae are a good source of available energy and crude protein (BSL and BSM) and can be incorporated in broiler diets as alternative protein and energy sources.
Optimized Surface Ion Trap Design for Tight Confinement and Separation of Ion Chains
Authors: Gerasin Ilya , Zhadnov Nikita , Kudeyarov Konstantin , Khabarova Ksienia , Kolachevsky Nikolay , Semerikov Ilya
Published: August 2024

Qubit systems based on trapped ultracold ions win one of the leading positions in the quantum computing field, demonstrating quantum algorithms with the highest complexity to date. Surface Paul traps for ion confinement open the opportunity to scale quantum processors to hundreds of qubits and enable high-connectivity manipulations on ions. To fabricate such a system with certain characteristics, the special design of a surface electrode structure is required. The depth of the trapping potential, the stability parameter, the secular frequency and the distance between an ion and the trap surface should be optimized for better performance. Here, we present the optimized design of a relatively simple surface trap that allows several important high-fidelity primitives: tight ion confinement, laser cooling, and wide optical access. The suggested trap design also allows us to perform an important basic operation, namely, splitting an ion chain into two parts.
C2-Symmetric Amino Acid Amide-Derived Organocatalysts
Authors: Al-Taie Zahraa S. , Coles Simon J. , Congreve Aileen , Ford Dylan , Green Lucy , Horton Peter N. , Jones Leigh F. , Kett Pippa , Kraehenbuehl Rolf , Murphy Patrick J. , Tizzard Graham J. , Willmore Niles B. , Wright Oliver T.
Published: August 2024

N-alkylated C2-symmetric amino acid amide derivatives were shown to catalyse the Michael addition of 2-hydroxy-1,4-napthoquinone to β-nitrostyrene, achieving a maximum ee of 44%. The corresponding trifluoroacetic acid salts also catalysed the aldol reaction between 4-nitrobenzaldehyde and hydroxyacetone, leading to the formation of predominantly syn-aldol products in up to 55% ee. Aspects of the solvent dependence of the aldol reaction and the H-bonding of the catalyst were investigated.