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Objective: This study aims to evaluate the clinical effects of Platelet Rich Plasma (PRP) and Hyaluronic Acid (HA) as individual treatments for mild to moderate Osteoarthritis (OA), and also examine the potential synergistic effects of PRP in combination with HA. Research continues to emerge examining the potential therapeutic efficacy of HA and PRP as autologous injectable treatments for joint arthritis. However, there is a paucity of research investigating the effects of combining HA and PRP on pain and functional status in patients with OA. Design: In this multicenter, randomized, controlled, double blind, prospective trial, 105 patients with mild to moderate knee osteoarthritis who met the study criteria were randomly allocated to one of three interventions: HA (n=36), PRP (n=36), or HA+PRP (n=33). Each patient received 3 intaarticular knee injections of their assigned substance, with 2 week intervals between each injection. Clinical outcomes were evaluated using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Visual Analogue Scale (VAS) questionnaire at baseline and after 1,3,6, and 12 months. Results: The study showed that the PRP group have significant reduction in VAS scores at 1 (p= 0.003), 3 (p= 0.0001), 6 (p= 0.0001) and 12 (p= 0.000) months when compared to HA. In addition, the PRP group illustrated greater improvement in WOMAC physical activity scale at 12 months (p= 0.008) when compared to the HA group. Combining HA and PRP resulted in a significant decreases in pain (p=0.0001) and functional limitation (p=0.0001) when compared to HA alone at 1 year post treatment; and significantly increased physical function at 1 (p=0.0004) and 3 (p=.011) months when compared to PRP alone. Conclusion: The findings of the study support the use of autologous PRP as an effective treatment of mild to moderate knee osteoarthritis. It also shows that the combination of HA and PRP resulted to better outcomes than HA alone up to 1 year and PRP alone up to 3 months. Furthermore, the results suggest that combination of PRP and HA could potentially provide better functional outcomes in the first 30 days after treatment with both PRP and HA alone.

Banana is one of the most consumed and popular fruits in all regions of the world, being cultivated mainly in tropical countries. It is not only a rich source of vitamins A, C, and B, calcium, iron, potassium, phosphorus, and other vitamins and nutrients, but it also contains several types of antioxidants with high nutritional value. In this context, the current study aimed to quantify the content of ascorbic acid, flavonoids, pigments, and minerals present in "Nanicão" bananas during the ripening process. As demonstrated, the level of flavonoids was higher in ripe and overripe fruits, whereas the mineral composition was high only at ripening stage 4 (more yellow than green) a stage that should be prioritized when recommending fruit consumption to the population deficient in these minerals. Regarding pigments, there was a reduction in chlorophylls a and b and an increase in carotenoids and anthocyanins in peels and pulps. PRACTICAL APPLICATION: Flavonoids are phenolic, bioactive compounds with proven antioxidant and anti-inflammatory activity and products of the plant's secondary metabolism. The degradation of chlorophylls and synthesis of carotenoids and anthocyanins, and as a consequence of the latter pigment, the increase in flavonoids in the pulp was evident during the monitoring of ripening, mainly in the fruit peels in relation to pigments. Minerals are essential elements, the main ones provided in balanced diets and important for dietary and nutritional health., (© 2024 Institute of Food Technologists.)

The mortality rate caused by parasitic worms on their hosts is of great concern and studies have been carried out to find molecules to reduce the prevalence, host-parasite interaction, and resistance of parasites to treatments. Existing drugs on the market are very often toxic and have many side effects, hence the need to find new, more active molecules. It has been demonstrated in several works that medicinal plants constitute a wide range of new molecules that can solve this problem. Several works have already been able to demonstrate that cyclic peptides of plant origin have shown good activity in the fight against different types of helminths. Therefore, this review aims to provide a general overview of the methods and techniques of extraction, isolation, activities and mechanisms of action of cyclotides and other cyclic peptides for application in the treatment of helminthic infections., Competing Interests: Declaration of Competing Interest Authors declare not conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Tuberculosis is caused by Mycobacterium tuberculosis (MTB) and is the leading cause of death from infectious diseases in the World. The search for new antituberculosis drugs is a high priority, since several drug-resistant TB-strains have emerged. Many nanotechnology strategies are being explored to repurpose or revive drugs. An interesting approach is to graft antimicrobial peptides (AMPs) to antibiotic-loaded nanoparticles. The objective of the present work was to determine the anti-MTB activity of rifampicin-loaded N-acetylcysteine-chitosan-based nanoparticles (NPs), conjugated with the AMP Ctx(Ile 21 )-Ha; against clinical isolates (multi- and extensively-drug resistant) and the H 37 Rv strain. The modified chitosan and drug-loaded NPs were characterized with respect to their physicochemical stability and their antimycobacterial profile, which showed potent inhibition (MIC values <0.977 μg/mL) by the latter. Furthermore, their accumulation within macrophages and cytotoxicity were determined. To understand the possible mechanisms of action, an in silico study of the peptide against MTB membrane receptors was performed. The results presented herein demonstrate that antibiotic-loaded NPs grafted with an AMP can be a powerful tool for revitalizing drugs against multidrug-resistant M. tuberculosis strains, by launching multiple attacks against MTB. This approach could potentially serve as a novel treatment strategy for various long-term diseases requiring extended treatment periods., Competing Interests: Declaration of competing interest All contributing authors declare no conflicts of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Studies on the role of nickel (Ni) in photosynthetic and antioxidant metabolism, as well as in flavonoid synthesis and biological fixation nitrogen in cowpea crop are scarce. The aim of this study was to elucidate the role of Ni in metabolism, photosynthesis and nodulation of cowpea plants. A completely randomized experiment was performed in greenhouse, with cowpea plants cultivated under 0, 0.5, 1, 2, or 3 mg kg -1 Ni, as Ni sulfate. In the study the following parameters were evaluated: activity of urease, nitrate reductase, superoxide dismutase, catalase and ascorbate peroxidase; concentration of urea, n-compounds, photosynthetic pigments, flavonoids, H 2 O 2 and MDA; estimative of gas exchange, and biomass as plants, yield and weight of 100 seeds. At whole-plant level, Ni affected root biomass, number of seeds per pot, and yield, increasing it at 0.5 mg kg -1 and leading to inhibition at 2-3 mg kg -1 (e.g. number of seeds per pot and nodulation). The whole-plant level enhancement by 0.5 mg Ni kg -1 occurred along with increased photosynthetic pigments, photosynthesis, ureides, and catalase, and decreased hydrogen peroxide concentration. This study presents fundamental new insights regarding Ni effect on N metabolism, and nodulation that can be helpful to increase cowpea yield. Considering the increasing population and its demand for staple food, these results contribute to the enhancement of agricultural techniques that increase crop productivity and help to maintain human food security., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Introduction: High quality corn silage depends on factors such as corn type, stage of crop development at harvest time, fermentation time, in addition to use or not of inoculants. This study aimed to investigate the impact of maturity stage, bacterial inoculation, and storage time on fermentation, aerobic stability, and nutritional characteristics of flint corn silage and their implications for corn silage management., Methods: A flint corn hybrid was harvested very early, early, and medium (at 250, 300 and 350 g dry matter (DM)/kg as fed, respectively) and ensiled in mini-silos without (control) or with Lentilactobacillus buchneri CNCM I-4323 at 1 × 10 5  cfu/g for 120, 240 and 360 d to investigate how these factors interact with each other., Results and Discussion: There was only a small increase (7 g/kg starch; p  = 0.003) in starch digestibility (starch-D) in the silages stored for 360 d when compared to that stored for 240 d, but with no difference for 120 d. Despite the reduced starch-D (526 vs. 694 g/kg starch; p  < 0.001), silages produced from medium harvest had higher ( p  < 0.001) starch content (317 vs. 137 g/kg DM) and higher amount of digestible starch (169 vs. 98.5 g/kg DM; p  < 0.001) compared to very early harvest. The 2-way interactions (inoculation × storage time and maturity × storage time) showed that inoculation of corn silage with L. buchneri increased ( p  < 0.001) the aerobic stability, and that more mature crop silage had higher aerobic stability (140 h; p  = 0.036) than the others (118 and 48.5 h for those silages from very early and early harvest)., Conclusion: The storage for a longer time (>120 d) with the goal of increasing silage digestibility did not occur. Harvesting whole-crop flint corn with 300 to 350 g/kg DM is desirable to have higher DM yield and starch accumulation. Inoculation with L. buchneri is recommended to preserve the silage against aerobic deterioration. This study has shown the importance of harvesting flint corn at the right time, and the need for inoculation with L. buchneri to ensure greater yield, starch accumulation, and silage preservation, if 120 days of storage are not exceeded., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Rossi, Andrade, Rabelo, Siqueira, Vicente, Silva, Silva and Reis.)

Objectives: To determine the potential impact of sex-specific disease-related characteristics on cardiovascular (CV) disease in axial spondyloarthritis (axSpA)., Methods: Cross-sectional study of the Spanish AtheSpAin cohort to study CV disease in axSpA. Data on carotid ultrasound and CV disease and disease-related features were collected., Results: 611 men and 301 women were recruited. Classic CV risk factors were significantly less prevalent in women, who also showed a lower frequency of carotid plaques (p = 0.001), lower carotid intima-media thickness (IMT) values ​​(p<0.001) and CV events (p = 0.008). However, after adjustment for classic CV risk factors, only the differences with respect to carotid IMT remained statistically significant. Women showed higher ESR at diagnosis (p = 0.038), and more active disease (ASDAS, p = 0.012, and BASDAI, p<0.001). They had shorter disease duration (p<0.001), lower prevalence of psoriasis (p = 0.008), less structural damage (mSASSS, p<0.001), and less mobility limitation (BASMI, p = 0.033). To establish whether these findings could lead to sex differences in CV disease burden, we compared the prevalence of carotid plaques in men and women with the same level of CV risk stratified according to the Systematic Coronary Risk Evaluation (SCORE). Men included in the low-moderate CV risk SCORE category had more carotid plaques (p = 0.050), along with longer disease duration (p = 0.004), higher mSASSS (p = 0.001) and psoriasis (p = 0.023). In contrast, in the high-very high-risk SCORE category, carotid plaques were observed more frequently in women (p = 0.028), who were characterized as having worse BASFI (p = 0.011), BASDAI (p<0.001) and ASDAS (p = 0.027)., Conclusion: Disease-related features may influence the expression of atherosclerosis in patients with axSpA. This may be especially applicable to women at high CV risk, characterized by greater disease severity and more severe subclinical atherosclerosis than men, suggesting a stronger interaction between disease activity and atherosclerosis in women with axSpA., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023. Published by Elsevier Inc.)

The incorrect use of conventional drugs for both prevention and control of intestinal infections has contributed to a significant spread of bacterial resistance. In this way, studies that promote their replacement are a priority. In the last decade, the use of antimicrobial peptides (AMP), especially Ctx(Ile 21 )-Ha AMP, has gained strength, demonstrating efficient antimicrobial activity (AA) against pathogens, including multidrug-resistant bacteria. However, gastrointestinal degradation does not allow its direct oral application. In this research, double-coating systems using alginate microparticles loaded with Ctx(Ile 21 )-Ha peptide were designed, and in vitro release assays simulating the gastrointestinal tract were evaluated. Also, the AA against Salmonella spp. and Escherichia coli was examined. The results showed the physicochemical stability of Ctx(Ile 21 )-Ha peptide in the system and its potent antimicrobial activity. In addition, the combination of HPMCAS and chitosan as a gastric protection system can be promising for peptide carriers or other low pH-sensitive molecules, adequately released in the intestine. In conclusion, the coated systems employed in this study can improve the formulation of new foods or biopharmaceutical products for specific application against intestinal pathogens in animal production or, possibly, in the near future, in human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objectives: To determine the potential impact of extra-articular manifestations (EAMs) on disease characteristics and cardiovascular (CV) risk in patients with axial spondylarthritis (axSpA)., Methods: This is a cross-sectional study from the AtheSpAin cohort, a Spanish multicenter cohort to study atherosclerosis in axSpA. Data on the history of CV events, subclinical carotid atherosclerosis, and disease-related features, including EAMs, were collected., Results: 888 axSpA patients were recruited. Concomitant acute anterior uveitis (AAU), psoriasis (PSO), and inflammatory bowel disease (IBD) were present in 177 (19.9%), 96 (10.8%), and 57 (6.4%) patients, respectively. When compared with axSpA patients without EAMs, a significant increase in past CV events was observed in patients with PSO (9% versus 4%, p = 0.048) and in those with at least one EAM (7% versus 4%, p = 0.032) or with more than one EAM (11% versus 4%, p = 0.022). The frequency of carotid plaques and the values of cIMT were higher in patients with EAMs than in those without EAMs, although only the univariable analysis for carotid plaques in patients with PSO (39% versus 30%, p = 0.038) and for cIMT in patients with AAU (665 ± 156 µm versus 637 ± 139 µm, p = 0.042) and those with at least one EAM (661 ± 155 µm versus 637 ± 139 µm, p = 0.024) showed significant results. In addition, patients with PSO or IBD were found to have specific disease-related features, such as higher ESR at diagnosis, and more frequent use of glucocorticoids and TNF inhibitors than those without EAMs. Also, PSO patients had more commonly peripheral involvement and those with AAU more severe radiographic damage than those without EAMs. The frequency of HLA B27 was higher in patients with AAU and lower in those with PSO or IBD compared to those without EAMs., Conclusion: Patients with axSpA and EAMs, in addition to displaying their own disease-related features, are likely to have an increased CV risk that appears proportional to the number of EAMs and could be related to proatherogenic factors other than traditional CV risk factors, such as the inflammatory load and the use of glucocorticoids., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Nanobiotechnology is a relatively unexplored area that has, nevertheless, shown relevant results in the fight against some diseases. Antimicrobial peptides (AMPs) are biomacromolecules with potential activity against multi/extensively drug-resistant bacteria, with a lower risk of generating bacterial resistance. They can be considered an excellent biotechnological alternative to conventional drugs. However, the application of several AMPs to biological systems is hampered by their poor stability and lifetime, inactivating them completely. Therefore, nanotechnology plays an important role in the development of new AMP-based drugs, protecting and carrying the bioactive to the target. This is the first review article on the different reported nanosystems using AMPs against bacteria listed on the WHO priority list. The current shortage of information implies a nanobiotechnological potential to obtain new drugs or repurpose drugs based on the AMP-drug synergistic effect., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

The importance of obtaining new compounds with improved antimicrobial activity is a current trend and challenge. Some polymers such as chitosan have shown promising bactericidal properties when they are structurally modified, which is due to the binding versatility provided by their free amines. Likewise, antimicrobial peptides (AMPs) have received attention in recent years because of their bactericidal activity that is similar to or even better than that of conventional drugs, and they exhibit a low induction rate of antimicrobial resistance. Herein, the modified AMP Ctx(Ile 21 )-Ha-Ahx-Cys was conjugated to chitosan using N -acetylcysteine as an intermediate by the carbodiimide method. Films were prepared using protonated chitosan in 1% acetic acid and Ctx(Ile 21 )-Ha-Ahx-Cys AMP dissolved in N -acetylcysteine-chitosan; 1.6 mmol of ethylcarbodiimide hydrochloride, 1.2 mmol of N -hydroxysulfosucchimide, and 0.1 mol L -1 of N -morpholino)ethanesulfonic acid buffer at pH 6.5 by continuous stirring at 100 × g for 10 min at 37 °C. Physicochemical properties were evaluated by Fourier-transform infrared spectroscopy, differential scanning calorimetry/thermogravimetric analysis, and X-ray diffraction to determine the mechanical properties, solubility, morphology, and thickness. Furthermore, the antimicrobial activities of chitosan-based conjugated films were evaluated against Staphylococcus aureus , Pseudomonas aeruginosa , Salmonella Typhimurium, and Escherichia coli . The results showed that the conjugation of a potent AMP could further increase its antibacterial activity and maintain its stable physicochemical properties. Therefore, the developed peptide-chitosan conjugate could be applied as an additive in surgical procedures to prevent and combat bacterial infection., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Objectives: To identify disease-related factors associated with subclinical atherosclerosis and cardiovascular (CV) events in a large series of patients with axial spondyloarthritis (axSpA) and to identify possible differences in the effect of the potential pro-atherogenic factors between ankylosing spondylitis (AS) non-radiographic axSpA (nr-axSpA)., Methods: This is a cross-sectional observational study of the AtheSpAin cohort, a Spanish multicenter cohort to study atherosclerosis in axSpA. Subclinical atherosclerosis determined by carotid ultrasound included assessment of carotid intima-media thickness (cIMT) and plaque detection., Results: 639 AS and 167 nr-axSpA patients were recruited. CV risk factors (CRF) and several disease-related factors showed a statistically significant association with subclinical atherosclerosis in the crude analysis. After adjustment for age, sex, and smoking (model 1), associations remained statistically significant for spinal mobility, inflammatory bowel disease, use of prednisone, and Disease-modifying antirheumatic drugs (DMARD) when assessing carotid plaques and for acute phase reactants (APR) at diagnosis, use of prednisone, DMARD, and TNF-inhibitors when measuring cIMT. In model 2, which also included classic CRF as confounding factors to identify axSpA features with a potential independent pro-atherogenic effect, the functional status was the only variable significantly associated with plaques and the use of prednisone and APR at diagnosis with cIMT. No association differences were found between both subtypes of patients. Besides, APR at diagnosis were also associated with subsequent development of CV events that had occurred in 33 patients., Conclusion: Apart from CRF, atherosclerotic disease in AxSpA is associated with disease-related factors such as inflammatory response and disease severity, with no differences between AS and nr-axSpA., (Copyright © 2022. Published by Elsevier Inc.)

Salmonella enterica subsp. enterica serovar Enteritidis ( S . Enteritidis) in poultry is most often transmitted by the fecal-oral route, which can be attributed to high population density. Upon encountering the innate immune response in a host, the pathogen triggers a stress response and virulence factors to help it survive in the host. The aim of this study was to evaluate the effect of hypromellose acetate/succinate (HPMCAS)-coated alginate microparticles containing the Ctx(Ile 21 )-Ha antimicrobial peptide (AMP) on both intestinal colonization and systemic infection of laying hens challenged with S . Enteritidis. The applied AMP microsystem reduced the bacterial load of S . Enteritidis in the liver, with a statistical significance between groups A (control, no Ctx(Ile 21 )-Ha peptide) and B (2.5 mg of Ctx(Ile 21 )-Ha/kg) at 2 days postinfection (dpi), potentially indicating the effectiveness of Ctx(Ile 21 )-Ha in the first stage of infection by S . Enteritidis. In addition, the results showed a significant decrease in the S . Enteritidis counts in the spleen and cecal content at 5 dpi; remarkably, no S . Enteritidis counts were observed in livers at 5, 7, and 14 dpi, regardless of the Ctx(Ile 21 )-Ha dosage ( p -value <0.0001). Using the Chi-square test, the effect of AMP microparticles on S . Enteritidis fecal excretion was also evaluated, and a significantly lower bacterial excretion was observed over 21 days in groups B and C, in comparison with the untreated control ( p- value <0.05). In summary, the use of HPMCAS-Ctx(Ile 21 )-Ha peptide microcapsules in laying hens drastically reduced the systemic infection of S . Enteritidis, mainly in the liver, indicating a potential for application as a feed additive against this pathogen.

Orbitides are bioactive head-to-tail natural cyclic peptides from plant species. Their bioactivity is intrinsically related to the main conformations adopted in solution, whose correct characterization represents an important bottleneck for medicinal chemistry applications. To date, NMR spectrosocopy has been the most frequently used technique to assess the secondary structure of orbitides. Despite the amount of structural information commonly available from NMR, its time scale frequently results in a limited conformational ensemble with a single mean structure, which may not represent the bioactive conformation. Additionally, problems with inter-residue NOE/ROE signals can reduce the accuracy and confidence of the 3D assignments. Vibrational circular dichroism (VCD), on the other hand, has been demostrated as a powerful tool to probe the stereostructure of chiral molecules, including peptides and proteins, with enhanced sensitivity to individual conformations in the condensed phase. Herein, we present the first VCD stereochemical investigation of orbitides. By combining IR/VCD experiments in ACN- d 3 and ACN- d 3 /D 2 O mixtures with DFT calculations in different levels of theory we were able to determine the solution-state conformational behavior, as well as the main structural restraints induced by cyclization, of the seven-residue orbitide pohlianin A and its linear precursor. VCD results indicated inverse γ-turns as the most prevalent structural motif for the linear precursor in partially aqueous solution, while type I and type VI β-turns were induced by the cyclization process, along with some classic γ-turns. In addition to the conformation of the cyclic peptide already described from NMR data, two previously unidentified conformations with distinct secondary structures were found to significantly populate the sample. This conformational discriminatory power of VCD for both linear and cyclic peptides in different solvent systems may lead to more accurate structural characterization of turn-rich peptidic natural products and help the design of conformationally-tailored peptides for more precise structure-activity relationship results.

Tetraethyl pyrophosphate (TEPP) is an organophosphate pesticide that irreversibly inhibits acetylcholinesterase (AChE). Cork powder or granules have been recommended as a sustainable sorbent to remove pesticides from water. In the present study, we evaluated the effectiveness of removing TEPP from water using wine corks to obtain cork granules as natural adsorbent, analyzing the TEPP effects on AChE activity in commercial enzyme from Electrophorus electricus and secreted by neuronal PC12 cells. TEPP inhibited AChE activity in a concentration-dependent manner. For the first time, we showed that different concentrations of TEPP diluted in water after adsorption experiments using cork granules decreased TEPP's inhibitory effects on AChE activity in commercial enzyme and neuronal PC12 cell culture medium. Our results suggest that the optimum removal of TEPP from water by corks was 91.4 ± 4.0%. Overall, the findings support the hypothesis that cork granules can be used to remediate pesticide-contaminated environments, such as those contaminated by organophosphate pesticides, and demonstrate a new application of a biochemical assay on AChE activity using a commercial enzyme or secreted by neuronal PC12 cells in culture as a possible methodologic strategy for evaluating the success of TEPP removal from water.

The diseases affecting the Central Nervous System (CNS) can have varied etiopathology, but they have in common silent progression, global incidence, and significant impacts on the quality of life of patients and public health systems. With the advance of biomedicine and pharmaceutical technology, new and more modern diagnostic methods and treatments were developed, repurposing the use of drugs currently available for the treatment of CNS diseases. An attractive approach is the use of alternative drug delivery platforms, such as nanocarriers, and less invasive administration routes, such as the noseto- brain, extensively explored for the delivery of drugs into the CNS. Despite many promising results, the nose-to-brain route has some physiological limitations that make it difficult to deliver drugs satisfactorily to exert therapeutic activity in the CNS. To overcome these limitations, nanostructured systems with mucoadhesive properties have stood out over the last few years in pharmaceutical R&D. In this review; we discuss how the noseto- brain route limitations can influence the delivery of drugs to the CNS and highlight the benefits that mucoadhesion can bring to these nanostructured systems. The main findings in the literature are brought together and discussed critically, focusing on how mucoadhesion can improve the biopharmaceutical properties of molecules used in the clinic, as well as their biological performance. Finally, conclusions are drawn about the points of strength of mucoadhesive nanosystems and the points that still need attention to successfully use the nose-to-brain route for the treatment of diseases that affect the CNS., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In the last few years, feed additives have been used in animal nutrition to improve nutrient utilization, health parameters and animal performance. However, the use of antibiotics as feed additives has allowed the occurrence of antimicrobial resistance (AMR), which can bring as a consequence, an increase in the morbidity and mortality of diseases that were previously treatable with antibiotics. In this context, antimicrobial peptides (AMP) have appeared as a promising strategy because they have multiple biological activities and represent a powerful strategy to prevent the development of resistant microorganisms. Despite the small number of studies applied in vivo, AMP appear as a potent alternative to the use of antibiotics in animal nutrition, due to an increase in feed efficiency and the prevention/treatment of some animal diseases. This review discusses the problems associated with antimicrobial resistance and the use of AMP as a strong candidate to replace conventional antibiotics, mainly in the animal industry., Competing Interests: We declare that we have no financial and personal relationships with other people or organizations that might inappropriately influence our work, and there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the content of this paper., (© 2021 Chinese Association of Animal Science and Veterinary Medicine. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

Microencapsulation is a potential biotechnological tool, which can overcome antimicrobial peptides (AMP) instabilities and reduce toxic side effects. Thus, this study evaluates the antibacterial activities of the Ctx(Ile 21 )-Ha AMP against multidrug-resistant (MDR) and non-resistant bacteria and develop and characterize peptide-loaded microparticles coated with the enteric polymers hydroxypropylmethylcellulose acetate succinate (HPMCAS) and hydroxypropylmethylcellulose phthalate (HPMCP). Ctx(Ile 21 )-Ha was obtained by solid phase peptide synthesis (SPPS) method, purified and characterized by HPLC and Mass Spectrometry. The peptide exhibited potent antibiotic activities against Salmonella enteritidis, Salmonella typhimurium, Pseudomonas aeruginosa (MDR), Acinetobacter baumannii (MDR), and Staphylococcus aureus (MDR). Ctx(Ile 21 )-Ha microencapsulation was performed by ionic gelation with high efficiency, maintaining the physical-chemical stability. Ctx(Ile 21 )-Ha coated-microparticles were characterized by DSC, TGA, FTIR-Raman, XRD and SEM. Hemolytic activity assay demonstrated that hemolysis was decreased up to 95% compared to single molecule. In addition, in vitro release control profile simulating different portions of gastrointestinal tract was performed and showed the microcapsules' ability to protect the peptide and release it in the intestine, aiming pathogen's location, mainly by Salmonella sp. Therefore, use of microencapsulated Ctx(Ile 21 )-Ha can be allowed as an antimicrobial controller in monogastric animal production as an oral feed additive (antimicrobial controller), being a valuable option for molecules with low therapeutic indexes or high hemolytic rates., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Axial spondyloarthritis (axSpA) patients are known to have a higher prevalence of several comorbidities, including, among others, an increased risk of atherosclerosis, hypertension, dyslipidemia, and diabetes. The purpose of the present study was to determine whether the sum of traditional cardiovascular (CV) risk factors is related to disease characteristics, such as disease activity, in patients with axSpA., Methods: A cross-sectional study that encompassed 804 patients with axSpA was conducted. Patients were assessed for the presence of five traditional CV risk factors (diabetes mellitus, dyslipidemia, hypertension, obesity, and smoking status), and disease activity measurements. A multivariable regression analysis was performed to evaluate whether the number of classic CV risk factors was independently associated with specific features of the disease, to include disease activity., Results: A multivariable analysis showed that Ankylosing Spondylitis Disease Activity Score-C reactive protein (ASDAS-CRP) activity score was significantly higher in patients with 1 [beta coefficient 0.3 (95% confidence interval (CI) 0.1-0.5), p  = 0.001] and ⩾2 [beta coefficient 0.5 (95% CI 0.3-0.7), p  = 0.000] CV risk factors compared with those without CV risk factors. Similarly, patients with 1 [OR 2.00 (95%CI 0.99-4.02), p  = 0.053] and ⩾2 [OR 3.39 (95%CI 1.82-6.31), p  = 0.000] CV risk factors had a higher odds ratio for the presence of high disease activity compared with the zero CV category. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) activity score was significantly associated with the number of CV risk factors, being higher in patients with more CV risk factors. These relationships showed a CV risk factor-dependent effect being beta coefficients and ORs higher for the effect of ⩾2 over 1 CV risk factor., Conclusion: Among patients with axSpA, as the number of traditional CV risk factors increased, disease activity similarly increases in an independent manner., Competing Interests: Conflict of interest statement: MAG-G and IF-A would like to acknowledge that they received grants/research supports from Abbott, MSD, Jansen, and Roche, as well as consultation fees from company-sponsored speakers bureaus associated with Abbott, Pfizer, Roche, Sanofi, Celgene, and MSD., (© The Author(s), 2021.)

Numerous environmental and endogenous factors affect the level of genetic diversity in natural populations. Genetic variability is the cornerstone of evolution and adaptation of species. However, currently, more and more plant species and local varieties (landraces) are on the brink of extinction due to anthropopression and climate change. Their preservation is imperative for the sake of future breeding programs. Gene banks have been created worldwide to conserve different plant species of cultural and economic importance. Many of them apply cryopreservation, a conservation method in which ultra-low temperatures (-135 °C to -196 °C) are used for long-term storage of tissue samples, with little risk of variation occurrence. Cells can be successfully cryopreserved in liquid nitrogen (LN) when the adverse effect of ice crystal formation and growth is mitigated by the removal of water and the formation of the so-called biological glass (vitrification). This state can be achieved in several ways. The involvement of key cold-regulated genes and proteins in the acquisition of cold tolerance in plant tissues may additionally improve the survival of LN-stored explants. The present review explains the importance of cryostorage in agronomy and presents an overview of the recent works accomplished with this strategy. The most widely used cryopreservation techniques, classic and modern cryoprotective agents, and some protocols applied in crops are considered to understand which parameters provide the establishment of high quality and broadly applicable cryopreservation. Attention is also focused on the issues of genetic integrity and functional genomics in plant cryobiology.

The constant use of synthetic antibiotics as growth promoters can cause bacterial resistance in chicks. Consequently, the use of these drugs has been restricted in different countries. In recent years, antimicrobial peptides have gained relevance due to their minimal capacity for bacterial resistance and does not generate toxic residues that harm the environment and human health. In this study, a Ctx(Ile 21 )-Ha antimicrobial peptide was employed, due to its previously reported great antimicrobial potential, to evaluate its application effects in laying chicks challenged with Salmonella Enteritidis, resistant to nalidixic acid and spectinomycin. For this, Ctx(Ile 21 )-Ha was synthesized, microencapsulated and coated with hypromellose phthalate (HPMCP) to be released in the intestine. Two different doses (20 and 40 mg of Ctx(Ile 21 )-Ha per kg of isoproteic and isoenergetic poultry feed) were included in the chick's food and administered for 28 days. Antimicrobial activity, effect and response as treatment were evaluated. Statistical results were analyzed in detail and indicate that the formulated Ctx(Ile 21 )-Ha peptide had a positive and significant effect in relation to the reduction of chick mortality in the first days of life. However, there was moderate evidence ( p = 0.07), not considered statistically significant, in the differences in laying chick weight between the control and microencapsulation treatment groups as a function of time. Therefore, the microencapsulated Ctx(Ile 21 )-Ha antimicrobial peptide can be an interesting and promising option in the substitution of conventional antibiotics.

Objectives: To compare the atherosclerosis disease burden between ankylosing spondylitis (AS) and non-radiographic (nr) axial spondyloarthritis (axSpA) and establish a model that allows to identify high-cardiovascular (CV) risk in axial spondyloarthritis patients., Methods: Cross-sectional study from the AtheSpAin cohort, a Spanish multicenter cohort aimed to study atherosclerosis in axSpA. Carotid ultrasound (US) was performed to determine the carotid intima-media wall thickness (cIMT) and detect the presence of carotid plaques. The European cardiovascular disease risk assessment model, the Systematic COronary Risk Evaluation (SCORE), was also applied., Results: A set of 639 patients with AS and 167 patients with nr-axSpA without history of CV events were recruited. AS patients were older showing more CV risk factors and higher values of C reactive protein and erythrocyte sedimentation rate (ESR) than those with nr-axSpA. However, no difference in the prevalence of carotid plaques or in the cIMT was found between both groups in the adjusted analysis. The percentage of patients reclassified from the low and moderate CV risk categories to the very high-risk category due to the presence of carotid plaques was comparable in AS and nr-axSpA (10.7% versus 10.1% and 40.5% versus 45.5%, respectively). A model containing age, BASFI and ESR applied to moderate risk axSpA patients identified 41% of these patients as having very high-risk patients with high specificity (88%)., Conclusion: The atherosclerosis burden is similar in nr-axSpA and AS. As occurred for AS, more than 40% of axSpA patients included in the category of moderate CV risk according to the SCORE are reclassified into very high risk after carotid US, and a clinically relevant proportion of them can be detected by applying a model containing age, BASFI and ESR., Competing Interests: Declaration of Competing Interest I am pleased to inform that the authors of this manuscript have no competing interests to declare, (Copyright © 2021 Elsevier Inc. All rights reserved.)

Paraquat is resistant to degradation by conventional treatments, being necessary to use treatments with greater effectiveness, such as advanced oxidative processes. In this work, different advanced oxidative processes were applied (Fenton, electro-Fenton, photoelectro-oxidation and photoelectro-Fenton) employing oxide electrodes to degrade Gramoxone, a commercial herbicide that contains paraquat in its composition. The degradation and formation of by-products were accompanied by high performance liquid chromatography, total organic carbon (TOC) and chemical oxygen demand (COD). The results showed that the photoelectro-Fenton process was the most efficient due to the synergistic effect, reaching 79% degradation of the initial compound and 82% and 71% removal of TOC and COD, respectively. After the application of the electro-Fenton and photoelectro-Fenton oxidation processes, short-chain carboxylic acids such as succinic acid, oxalic acid, acetic acid and formic acid were identified as by-products of the oxidation of Gramoxone. The results were satisfactory and deserve to be highlighted, as a commercial formulation was used, making the scenario more realistic.

There is no use restriction associated with bees for many fungicides used in agriculture; however, this does not always mean that these pesticides are harmless for these nontarget organisms. We investigated whether the fungicide pyraclostrobin, which acts on fungal mitochondria, also negatively affects honey bee mitochondrial bioenergetics. Honey bees were collected from 5 hives and anesthetized at 4 °C. The thoraces were separated, and mitochondria were isolated by grinding, filtering, and differential centrifugation. An aliquot of 0.5 mg of mitochondrial proteins was added to 0.5 mL of a standard reaction medium with 4 mM succinate (complex II substrate) plus 50 nM rotenone (complex I inhibitor), and mitochondrial respiration was measured at 30 °C using a Clark-type oxygen electrode. Mitochondrial membrane potential was determined spectrofluorimetrically using safranin O as a probe, and adenosine triphosphate (ATP) synthesis was determined by chemiluminescence. Pyraclostrobin at 0 to 50 μM was tested on the mitochondrial preparations, with 3 repetitions. Pyraclostrobin inhibited mitochondrial respiration in a dose-dependent manner at concentrations of 10 μM and above, demonstrating typical inhibition of oxidative phosphorylation. Pyraclostrobin also promoted a decline in the mitochondrial membrane potential at doses of 5 μM and above and in ATP synthesis at 15 μM and above. We conclude that pyraclostrobin interferes with honey bee mitochondrial function, which is especially critical for the energy-demanding flight activity of foraging bees. Environ Toxicol Chem 2020;39:1267-1272. © 2020 SETAC., (© 2020 SETAC.)

Cyclodextrin (CD) is a conical compound used in food and pharmaceutical industry to complexation of hydrophobic substances. It is a product of microbial enzymes which converts starch into CD during their activity. We aim to detect CD using active-electrode biosensor of SnO 2 . They were grown on active electrode by the VLS method. The CD consists of several glucose units which have hydroxyl groups which tend to bind to interface states present in nanowires changing their conductivity. Experimental results of electrical conductivity at different CD concentrations are presented. A model that describes the influence of adsorbed glucose on nanowires and its electrical properties is also presented. Some general observations are performed on the applicability of the CD adsorption method by the nanowire-based biosensor.

Polymyalgia rheumatica (PMR) is an inflammatory disease characterized by bilateral pain involving predominantly the shoulders and proximal aspects of the arms and less commonly the neck and the pelvic girdle. This review discusses briefly the main epidemiological data and clinical features of this condition. Especial attention is paid in the management of the disease. For this reason, both the classic management and the impact of new therapies are discussed in depth. In general, patients with PMR experience a rapid response to 12.5-25 mg/prednisone/day in less than a week. Patients with poor response to glucocorticoids or with relapsing disease require other therapies aimed mainly to spare glucocorticoids. Among them, methotrexate is the most commonly used. Nevertheless, different studies indicate that this agent yields only a modest effect. Biologic therapies against the main cytokines involved in the pathogenesis of the disease have been used in refractory patients. However, randomized controlled trials do not support the use of anti-tumor necrosis factor agents in PMR. In contrast, several case series and retrospective studies highlight the efficacy of the anti-interleukin-6 receptor tocilizumab in PMR. Nonetheless, controlled trials are needed to fully establish the beneficial effect of this agent. The potential favorable effect of the Janus-kinase inhibitors and new anti-interleukin-6 antagonists remains to be determined., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: To investigate the genetic background influencing the development of cardiovascular (CV) disease in patients with rheumatoid arthritis (RA)., Methods: We performed a genome-wide association study (GWAS) in which, after quality control and imputation, a total of 6,308,944 polymorphisms across the whole genome were analyzed in 2,989 RA patients of European origin. Data on subclinical atherosclerosis, obtained through assessment of carotid intima-media thickness (CIMT) and presence/absence of carotid plaques by carotid ultrasonography, were available for 1,355 individuals., Results: A genetic variant of the RARB gene (rs116199914) was associated with CIMT values at the genome-wide level of significance (minor allele [G] β coefficient 0.142, P = 1.86 × 10 -8 ). Interestingly, rs116199914 overlapped with regulatory elements in tissues related to CV pathophysiology and immune cells. In addition, biologic pathway enrichment and predictive protein-protein relationship analyses, including suggestive GWAS signals of potential relevance, revealed a functional enrichment of the collagen biosynthesis network related to the presence/absence of carotid plaques (Gene Ontology no. 0032964; false discovery rate-adjusted P = 4.01 × 10 -3 ). Furthermore, our data suggest potential influences of the previously described candidate CV risk loci NFKB1, MSRA, and ZC3HC1 (P = 8.12 × 10 -4 , P = 5.94 × 10 -4 , and P = 2.46 × 10 -4 , respectively)., Conclusion: The present findings strongly suggest that genetic variation within RARB contributes to the development of subclinical atherosclerosis in patients with RA., (© 2018 The Authors. Arthritis & Rheumatology published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology.)

Objective: To describe nailfold videocapillaroscopy (NVC) features of patients with antisynthetase syndrome (AS) and to investigate possible correlations with clinical and serological features of the disease., Methods: We retrospectively analyzed NVC images of 190 patients with AS [females/males 3.63, mean age 49.7 ± 12.8 yrs, median disease duration 53.7 mos (interquartile range 82), 133 anti-Jo1 and 57 non-anti-Jo1-positive patients]. For each patient, we examined number of capillaries, giant capillaries, microhemorrhages, avascular areas, ramified capillaries, and the presence of systemic sclerosis (SSc)-like pattern. Finally, we correlated NVC features with clinical and serological findings of patients with AS. Concomitantly, a historical cohort of 75 patients with antinuclear antibody-negative primary Raynaud phenomenon (RP) and longterm followup was used as a control group (female/male ratio 4.13/1, mean age 53.9 ± 17.6 yrs) for NVC measures., Results: NVC abnormalities were observed in 62.1% of AS patients compared with 29.3% of primary RP group (p < 0.001). An SSc-like pattern was detected in 67 patients (35.3%) and it was associated with anti-Jo1 antibodies (p = 0.002) and also with a longer disease duration (p = 0.004). Interestingly, there was no significant correlation between the presence of SSc-like pattern and RP, and only 47% of patients with SSc-like pattern had RP., Conclusion: NVC abnormalities are commonly observed in AS, independently from the occurrence of RP. The presence of an SSc-like pattern could allow identification of a more defined AS subtype, and prospective studies could confirm the association with clinical and serological features of AS.

Actinoporins sticholysin I and sticholysin II (St I, St II) are proposed to lyse model and biomembranes via toroidal pore formation by their N-terminal domain. Based on the hypothesis that peptide fragments can reproduce the structure and function of this domain, the behavior of peptides containing St I residues 12-31 (StI12-31), St II residues 11-30 (StII11-30), and its TOAC-labeled analogue (N-TOAC-StII11-30) was examined. Molecular modeling showed a good match with experimental structures, indicating amphipathic α-helices in the same regions as in the toxins. CD spectra revealed that the peptides were essentially unstructured in aqueous solution, acquiring α-helical conformation upon interaction with micelles and large unilamellar vesicles (LUV) of variable lipid composition. Fluorescence quenching studies with NBD-containing lipids indicated that N-TOAC-StII11-30's nitroxide moiety is located in the membranes polar head group region. Pyrene-labeled phospholipid inter-leaflet redistribution suggested that the peptides form toroidal pores, according to the mechanism of action proposed for the toxins. Binding occurred only to negatively charged LUV, indicating the importance of electrostatic interactions; in contrast the peptides bound to both negatively charged and zwitterionic micelles, pointing to a lesser influence of these interactions. In addition, differences between bilayers and micelles in head group packing and in curvature led to differences in peptide-membrane interaction. We propose that the peptides topography in micelles resembles that of the toxins in the toroidal pore. The peptides mimicked the toxins permeabilizing activity, St II peptides being more effective than StI12-31. To our knowledge, this is the first demonstration that differences in the toxins N-terminal amphipathic α-helix play a role in the difference between St I and St II activities., Competing Interests: The authors have declared that no competing interests exist.

Human dihydroorotate dehydrogenase (HsDHODH) enzyme has been studied as selective target for inhibitors to block the enzyme activity, intending to prevent proliferative diseases. The N-terminal microdomain seems to play an important role in the enzyme function. However, the molecular mechanism of action and dynamics of this region are not totally understood yet. This study analyzes the interaction and conformation in model membranes of HsDHODH microdomain using peptide analogues containing the paramagnetic amino acid TOAC at strategic positions. In buffer solution, the analogues presented a disordered conformation, but acquired a high content of α-helical structure in membrane mimetics, which was found to be lipid dependent. The microdomain peptide structure in micelles showed a very different peptide conformation when compared to the reported crystal structure, displaying a conformational flexibility of its helices, promoted by the connecting loop, which might be functionally relevant. Electron spin resonance in membrane compositions containing POPC, POPE, and cardiolipin showed that interaction of the analogues was enhanced by the presence of cardiolipin, indicating that the microdomain preferentially interacts with cardiolipin-containing membranes. Therefore, the great flexibility of the microdomain and the cardiolipin affinity should be considered in further studies aimed at finding new inhibitory compounds to fight proliferative diseases.

Viral membrane fusion is an orchestrated process triggered by membrane-anchored viral fusion glycoproteins. The S2 subunit of the spike glycoprotein from severe acute respiratory syndrome (SARS) coronavirus (CoV) contains internal domains called fusion peptides (FP) that play essential roles in virus entry. Although membrane fusion has been broadly studied, there are still major gaps in the molecular details of lipid rearrangements in the bilayer during fusion peptide-membrane interactions. Here we employed differential scanning calorimetry (DSC) and electron spin resonance (ESR) to gather information on the membrane fusion mechanism promoted by two putative SARS FPs. DSC data showed the peptides strongly perturb the structural integrity of anionic vesicles and support the hypothesis that the peptides generate opposing curvature stresses on phosphatidylethanolamine membranes. ESR showed that both FPs increase lipid packing and head group ordering as well as reduce the intramembrane water content for anionic membranes. Therefore, bending moment in the bilayer could be generated, promoting negative curvature. The significance of the ordering effect, membrane dehydration, changes in the curvature properties and the possible role of negatively charged phospholipids in helping to overcome the high kinetic barrier involved in the different stages of the SARS-CoV-mediated membrane fusion are discussed.

The human enzyme dihydroorotate dehydrogenase (HsDHODH) has been studied for being a target for development of new antineoplasic and antiproliferative drugs. The synthetic peptide N-t(DH) represents the N-terminal microdomain of this enzyme, responsible for anchoring it to the inner mitochondrial membrane. Also, it is known to harbor quinones that are essential for enzyme catalysis. Here we report structural features of the peptide/membrane interactions obtained by using CD and DEER spectroscopic techniques, both in micelles and in lipid vesicles. The data revealed different peptide conformational states in micelles and liposomes, which could suggest that this microdomain acts in specific regions or areas of the mitochondria, which can be related with the control of the quinone access to the HsDHODH active site. This is the first study to report on conformational changes of the HsDHODH N-terminal microdomain through a combination of CD and DEER spectroscopic techniques.

The N-terminus of the human dihydroorotate dehydrogenase (HsDHODH) has been described as important for the enzyme attachment in the inner mitochondrial membrane and possibly to regulate enzymatic activity. In this study, we synthesized the peptide acetyl-GDERFYAEHLMPTLQGLLDPESAHRL AVRFTSLGamide, comprising the residues 33-66 of HsDHODH N-terminal conserved microdomain. Langmuir monolayers and circular dichroism (CD) were employed to investigate the interactions between the peptide and membrane model, as micelles and monolayers of the lipids phosphatidylcholine (PC), 3-phosphatidylethanolamine (PE) and cardiolipin (CL). These lipids represent the major constituents of inner mitochondrial membranes. According to CD data, the peptide adopted a random structure in water, whereas it acquired α-helical structures in the presence of micelles. The π-A isotherms and polarization- modulated infrared reflection-absorption spectroscopy on monolayers showed that the peptide interacted with all lipids, but in different ways. In DPPC monolayers, the peptide penetrated into the hydrophobic region. The strongest initial interaction occurred with DPPE, but the peptide was expelled from this monolayer at high surface pressures. In CL, the peptide could induce a partial dissolution of the monolayer, leading to shorter areas at the monolayer collapse. These results corroborate the literature, where the HsDHODH microdomain is anchored into the inner mitochondrial membrane. Moreover, the existence of distinct conformations and interactions with the different membrane lipids indicates that the access to the enzyme active site may be controlled not only by conformational changes occurring at the microdomain of the protein, but also by some lipid-protein synergetic mechanism, where the HsDHODH peptide would be able to recognize lipid domains in the membrane.

Objective: The interleukin 2 (IL-2) and interleukin 21 (IL-21) locus at chromosome 4q27 has been associated with several autoimmune diseases, and both genes are related to immune system functions. The aim of this study was to evaluate the role of the IL-2/IL-21 locus in systemic sclerosis (SSc)., Patients and Methods: The case control study included 4493 SSc Caucasian patients and 5856 healthy controls from eight Caucasian populations (Spain, Germany, The Netherlands, USA, Italy, Sweden, UK and Norway). Four single nucleotide polymorphisms (rs2069762, rs6822844, rs6835457 and rs907715) were genotyped using TaqMan allelic discrimination assays., Results: We observed evidence of association of the rs6822844 and rs907715 variants with global SSc (pc=6.6E-4 and pc=7.2E-3, respectively). Similar statistically significant associations were observed for the limited cutaneous form of the disease. The conditional regression analysis suggested that the most likely genetic variation responsible for the association was the rs6822844 polymorphism. Consistently, the rs2069762A-rs6822844T-rs6835457G-rs907715T allelic combination showed evidence of association with SSc and limited cutaneous SSc subtype (pc=1.7E-03 and pc=8E-4, respectively)., Conclusions: These results suggested that the IL-2/IL-21 locus influences the genetic susceptibility to SSc. Moreover, this study provided further support for the IL-2/IL-21 locus as a common genetic factor in autoimmune diseases.

Antimicrobial peptides (AMPs) isolated from several organisms have been receiving much attention due to some specific features that allow them to interact with, bind to, and disrupt cell membranes. The aim of this paper was to study the interactions between a membrane mimetic and the cationic AMP Ctx(Ile(21))-Ha as well as analogues containing the paramagnetic amino acid 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC) incorporated at residue positions n = 0, 2, and 13. Circular dichroism studies showed that the peptides, except for [TOAC(13)]Ctx(Ile(21))-Ha, are unstructured in aqueous solution but acquire different amounts of α-helical secondary structure in the presence of trifluorethanol and lysophosphocholine micelles. Fluorescence experiments indicated that all peptides were able to interact with LPC micelles. In addition, Ctx(Ile(21))-Ha and [TOAC(13)]Ctx(Ile(21))-Ha peptides presented similar water accessibility for the Trp residue located near the N-terminal sequence. Electron spin resonance experiments showed two spectral components for [TOAC(0)]Ctx(Ile(21))-Ha, which are most likely due to two membrane-bound peptide conformations. In contrast, TOAC(2) and TOAC(13) derivatives presented a single spectral component corresponding to a strong immobilization of the probe. Thus, our findings allowed the description of the peptide topology in the membrane mimetic, where the N-terminal region is in dynamic equilibrium between an ordered, membrane-bound conformation and a disordered, mobile conformation; position 2 is most likely situated in the lipid polar head group region, and residue 13 is fully inserted into the hydrophobic core of the membrane.

The increase in bacterial resistance to current antibiotics has led to the development of new active molecules. We have isolated the antimicrobial peptide Ctx-Ha from the skin secretion of the frog Hypsiboas albopunctatus. The aim of the present work was to elucidate the mechanism of action of this new antimicrobial peptide. The sequence similarity with Ceratotoxin, the pore size, and the pore-like release of carboxyfluorescein from vesicles indicated that Ctx(Ile21)-Ha has a mechanism of action based on the barrel- stave model. In a second part of this work, we synthesized three analogues to provide information about the relationship between the peptide's structure and its biological activity. Ctx(Ile21)-Ha-VD 16, Ctx(Ile21)- Ha-VD 5,16 and Ctx(Ile21)-Ha-I9K were designed to disrupt the peptide's helical structure and change the hydrophobicity/ hydrophilicity and amphipathicity of the apolar face in order to uncouple the antimicrobial activity of Ctx(Ile21)-Ha from its hemolytic activity. To evaluate the effects of the amino acid substitutions on peptide conformation, secondary structure was accessed using CD measurements. The peptides presented a high amount of α-helical structure in the presence of TFE and LPC. The CD data showed that destruction of the amphipathic α-helix by the replacing isoleucine by lysine is less harmful to the structure than D-amino acid substitutions. Biological tests demonstrated that all peptides have activity. Nevertheless, the peptide Ctx(Ile21)-Ha-I9K showed the highest value of therapeutic index. Our findings suggest that these peptides are potential templates for the development of new antimicrobial drugs. These studies highlight the importance of single amino acid modification as a tool to modulate the biological activity of antimicrobial peptides.

It is well known that cationic antimicrobial peptides (cAMPs) are potential microbicidal agents for the increasing problem of antimicrobial resistance. However, the physicochemical properties of each peptide need to be optimized for clinical use. To evaluate the effects of dimerization on the structure and biological activity of the antimicrobial peptide Ctx-Ha, we have synthesized the monomeric and three dimeric (Lys-branched) forms of the Ctx-Ha peptide by solid-phase peptide synthesis using a combination of 9-fluorenylmethyloxycarbonyl (Fmoc) and t-butoxycarbonyl (Boc) chemical approaches. The antimicrobial activity assay showed that dimerization decreases the ability of the peptide to inhibit growth of bacteria or fungi; however, the dimeric analogs displayed a higher level of bactericidal activity. In addition, a dramatic increase (50 times) in hemolytic activity was achieved with these analogs. Permeabilization studies showed that the rate of carboxyfluorescein release was higher for the dimeric peptides than for the monomeric peptide, especially in vesicles that contained sphingomyelin. Despite different biological activities, the secondary structure and pore diameter were not significantly altered by dimerization. In contrast to the case for other dimeric cAMPs, we have shown that dimerization selectively decreases the antimicrobial activity of this peptide and increases the hemolytic activity. The results also show that the interaction between dimeric peptides and the cell wall could be responsible for the decrease of the antimicrobial activity of these peptides.

The use of very highly substituted resins has been avoided for peptide synthesis due to the aggravation of chain-chain interactions within beads. To better evaluate this problem, a combined solvation-peptide synthesis approach was herein developed taking as models, several peptide-resins and with peptide contents values increasing up to near 85%. Influence of peptide sequence and loading to solvation characteristics of these compounds was observed. Moreover, chain-chain distance and chain concentration within the bead were also calculated in different loaded conditions. Of note, a severe shrinking of beads occurred during the α-amine deprotonation step only when in heavily loaded resins, thus suggesting the need for the modification of the solvent system at this step. Finally, the yields of different syntheses in low and heavily loaded conditions were comparable, thus indicating the feasibility of applying this latter "prohibitive" chemical synthesis protocol. We thought these results might be basically credited to the possibility, without the need of increasing molar excess of reactants, of carrying out the coupling reaction in higher concentration of reactants - near three to seven folds - favored by the use of smaller amount of resin. Additionally, the alteration in the solvent system at the α-amine deprotonation step might be also improving the peptide synthesis when in heavily loaded experimental protocol., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Interleukin-15 (IL-15) is thought to be involved in the physiopathological mechanisms of RA and it can be detected in the serum and the synovial fluid of inflamed joints in patients with RA but not in patients with osteoarthritis or other inflammatory joint diseases. Therefore, the objective of this work is to analyse whether serum IL-15 (sIL-15) levels serve as a biomarker of disease severity in patients with early arthritis (EA)., Methodology and Results: Data from 190 patients in an EA register were analysed (77.2% female; median age 53 years; 6-month median disease duration at entry). Clinical and treatment information was recorded systematically, especially the prescription of disease modifying anti-rheumatic drugs. Two multivariate longitudinal analyses were performed with different dependent variables: 1) DAS28 and 2) a variable reflecting intensive treatment. Both included sIL-15 as predictive variable and other variables associated with disease severity, including rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPA). Of the 171 patients (638 visits analysed) completing the follow-up, 71% suffered rheumatoid arthritis and 29% were considered as undifferentiated arthritis. Elevated sIL-15 was detected in 29% of this population and this biomarker did not overlap extensively with RF or ACPA. High sIL-15 levels (β Coefficient [95% confidence interval]: 0.12 [0.06-0.18]; p<0.001) or ACPA (0.34 [0.01-0.67]; p = 0.044) were significantly and independently associated with a higher DAS28 during follow-up, after adjusting for confounding variables such as gender, age and treatment. In addition, those patients with elevated sIL-15 had a significantly higher risk of receiving intensive treatment (RR 1.78, 95% confidence interval 1.18-2.7; p = 0.007)., Conclusions: Patients with EA displaying high baseline sIL-15 suffered a more severe disease and received more intensive treatment. Thus, sIL-15 may be a biomarker for patients that are candidates for early and more intensive treatment.

Objectives: To assess the influence of the interleukin (IL)2-IL21 rs6822844 G/T polymorphism in the susceptibility to biopsy-proven giant cell arteritis (GCA) and in the clinical spectrum of manifestations of this vasculitis., Methods: Two hundred and seventy-two biopsy-proven GCA patients were included in this study. DNA from patients and matched controls (n=791) was obtained from peripheral blood. Samples were genotyped for the rs6822844 polymorphism using a predesigned TaqMan allele discrimination assay and by polymerase chain reaction amplification., Results: No significant differences in the allele and genotype frequencies between biopsy-proven GCA patients and controls were observed. However, the stratification of GCA patients disclosed some differences according to gender and ischemic manifestations of the disease. In this regard, the frequency of the minor allele T was increased in males (14.8%) compared to females (8.4%) (odds ratio-OR:1.89 (95% confidence interval-CI: 1.09-3.28); p=0.02; Bonferroni adjustment p=0.12). Also, minor allele T frequency was increased in GCA patients with severe ischemic complications (12.8%) compared to those without severe ischemic complications (7.7%) (OR:1.72 (95% CI: 0.97-3.05); p=0.05; Bonferroni adjustment p=0.30), and specifically in patients with jaw claudication (13.7% versus 8.2% in those without jaw claudication; OR:1.76 (95% CI: 1.02-3.04); p=0.04; Bonferroni adjustment p=0.24)., Conclusions: IL2-IL21 rs6822844 polymorphism does not appear to be a genetic risk factor for susceptibility to biopsy-proven GCA. However, this gene polymorphism may contribute to the different phenotypic expression of this vasculitis, in particular in the development of ischemic complications of the disease.

Objective: Giant cell arteritis (GCA) is a complex polygenic disease in which more than 1 genetic locus is likely to contribute to disease susceptibility and clinical expression. BANK, an adaptor molecule, has been suggested to participate in the B cell antigen receptors-mediated calcium homeostasis. We assessed for the first time the implication of BANK1 functional variants in susceptibility to GCA., Methods: Two hundred twenty-two patients with biopsy-proven GCA and 534 matched controls were assessed. DNA from patients and controls was obtained from peripheral blood. Samples were genotyped for 3 putative functional BANK1 gene polymorphisms (rs17266594 T/C, rs10516487 G/A, rs3733197 G/A) using a TaqMan allele discrimination assay., Results: No significant differences were observed in genotype distribution between patients with biopsy-proven GCA and controls for these 3 gene polymorphisms. A trend for a decreased risk of having GCA was observed in individuals carrying the BANK1 rs3733197 GG genotype (patients with GCA 43.9% compared to 51.6% in controls; p = 0.06, OR 0.73, 95% CI 0.53-1.02). The frequency of BANK1 rs3733197 allele G was marginally decreased in patients with biopsy-proven GCA compared to controls (p = 0.09, OR 0.82, 95% CI 0.64-1.04). Haplotype analysis of 3-single-nucleotide polymorphisms found no statistically significant differences between patients with GCA and controls. No significant differences for the BANK1 gene polymorphisms were found when patients were stratified according to specific clinical features of the disease., Conclusion: Our results do not support a major implication of the BANK1 locus in susceptibility to GCA.