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Optimization of the efficiency of the photocatalytic degradation of organic and pharmaceutical pollutants represents a matter of fundamental and practical interest. The present experimental and DFT study deals with evaluation of OH radical binding energy as a simple computational descriptor of the catalytic activity of d- metal-decorated TiO 2 photocatalysts for the photodegradation of the widely used antibiotic ciprofloxacin. Five d- metals commonly used in catalytic materials (Zr, Pt, Pd, Fe, and Cu) were deposited on the TiO 2 surface, and the obtained photocatalysts were characterized experimentally (XRPD, ICP-OES, and SEM) and theoretically (DFT). Attention was also paid to the mechanistic insights and degradation byproducts (based on UV-Vis spectrometry and LC/MS analysis) in order to obtain systematic insight into their structure/performance relationships and confirm the proposed model of the degradation process based on OH radical reactivity.

Gestational hypertension (GH) and preeclampsia (PE) are associated with the onset of hypertension. This study aimed to investigate whether the blood pressure (BP) pattern in GH is associated with the prevalence of hypertension later in life. In this prospective cohort study pregnant women screened for GH underwent medical history, laboratory analysis, ambulatory blood pressure monitoring (AMBP), and transthoracic echocardiography (with left ventricular global longitudinal strain (LVGLS)) assessment. Overall, 138 GH (67 non-dippers and 71 dippers), 55 preeclamptic, and 72 normotensive pregnant controls were included. Women were followed in the postpartum period, first after 6 weeks and later on, for the occurrence of hypertension. The median follow-up was 8.97 years (8.23; 9.03). Non-dippers and PE compared with normotensives and dippers had a higher prevalence of hypertension onset ( p < 0.01), as well as significantly reduced absolute values of LVGLS during pregnancy, after delivery, and at the time of onset of hypertension during follow-up ( p < 0.01). Night-time diastolic BP, LVGLS, age, and left ventricular ejection fraction were the strongest predictors of postpartum onset of hypertension. The non-dipping BP pattern in GH was significantly associated with the onset of hypertension later in life, as well as with decreased systolic function.

Fatigue is one of the most frequent complaints of patients with multiple sclerosis (MS). The Fatigue Impact Scale (FIS), one of the 30 available fatigue questionnaires, is commonly applied because it evaluates multidimensional aspects of fatigue. The chief objectives of this study were to validate FIS and evaluate the psychometric properties of MS patients in Serbia. One hundred and twenty-one (121) MS patients and one hundred and twenty-two (122) age-, gender- and education-matched healthy control (HC) subjects completed the FIS and the Beck Depression Inventory. Internal consistency of the FIS subscales was determined using Cronbach's Alpha Coefficient. Test/retest reliability with an intra-class correlation coefficient (ICC) for each FIS subscale was performed. The total FIS score and subscale scores showed statistically significant differences between the MS patients and the HC subjects in both FIS sessions. Cronbach's Alpha was 0.966. All ICCs were statistically significant ( p < 0.05). The Serbian version of this instrument may be useful as a clinical measure for fatigue and functionality in patients with MS.

Recent advances in regenerative medicine provide encouraging strategies to produce artificial skin substitutes. Gelatin scaffolds are successfully used as wound-dressing materials due to their superior properties, such as biocompatibility and the ability to mimic the extracellular matrix of the surrounding environment. In this study, five gelatin combination solutions were prepared and successfully electrospun using an electrospinning technique. After careful screening, the optimal concentration of the most promising combination was selected for further investigation. The obtained scaffolds were crosslinked with 25% glutaraldehyde vapor and characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. The incorporation of antibiotic agents such as ciprofloxacin hydrochloride and gentamicin sulfate into gelatin membranes improved the already existing antibacterial properties of antibiotic-free gelatin scaffolds against Pseudomonas aeruginosa and Staphylococcus aureus . Also, the outcomes from the in vivo model study revealed that skin regeneration was significantly accelerated with gelatin/ciprofloxacin scaffold treatment. Moreover, the gelatin nanofibers were found to strongly promote the neoangiogenic process in the in vivo chick embryo chorioallantoic membrane assay. Finally, the combination of gelatin's extracellular matrix and antibacterial agents in the scaffold suggests its potential for effective wound-healing treatments, emphasizing the importance of gelatin scaffolds in tissue engineering.

The development of turn-based inhibitors of protein-protein interactions has attracted considerable attention in medicinal chemistry. Our group has synthesized a series of peptides derived from an amino-functionalized ferrocene to investigate their potential to mimic protein turn structures. Detailed DFT and spectroscopic studies (IR, NMR, CD) have shown that, for peptides, the backbone chirality and bulkiness of the amino acid side chains determine the hydrogen-bond pattern, allowing tuning of the size of the preferred hydrogen-bonded ring in turn-folded structures. However, their biological potential is more dependent on their lipophilicity. In addition, our pioneering work on the chiroptical properties of aminoferrocene-containing peptides enables the correlation of their geometry with the sign of the CD signal in the absorption region of the ferrocene chromophore. These studies have opened up the possibility of using aminoferrocene and its derivatives as chirooptical probes for the determination of various chirality elements, such as the central chirality of amino acids and the helicity of peptide sequences.

The overexploitation of the western Pacific Ocean has expanded the sea cucumber fishery into new regions to supply the Asian market. In 2013, sea cucumbers were removed from the Croatian marine protected species list, and commercial fishery took place for a short period (2017-2018) in the Eastern Adriatic Sea. However, holothuroid species are difficult to distinguish. Holothuria mammata is a species that has rarely been reported in this region and strongly resembles the common species Holothuria tubulosa . This is the first study to assess the genetic diversity of sea cucumbers in the Adriatic Sea using genetic barcoding of the mitochondrial gene cytochrome c oxidase subunit 1 ( COI ). Specimens for barcoding were collected from the northern and central Adriatic, along with a specimen that had been previously identified as H. sp. cf. mammata based on its morphological characteristics. While genetic analyses showed identified this specimen as H. tubulosa , 30% of the collected specimens were genetically identified as H. mammata . These results call into question the historically accepted sea cucumber assemblage in the Adriatic Sea, which regarded H. mammata as a rare species and generally disregarded its presence in large census studies. Such species distribution data are extremely important in developing and monitoring a sustainable fishery.

(1) Background: An increasing use of pharmaceutics imposes a need for the permanent development of efficient strategies, including the tailoring of highly specific new materials for their removal from the environment. Photocatalytic degradation has been the subject of increasing interest of the researchers in the field. (2) Methods: This paper is focused on the investigation of the possibility to deposit a thin metal layer on a TiO 2 surface and study its photocatalytic performance for the degradation of ciprofloxacin using a combination of theoretical and experimental methods. (3) Results: Based on the extensive DFT screening of 24 d-metals' adhesion on TiO 2 , Cu was selected for further work, due to the satisfactory expected stability and good availability. The (Cu)TiO 2 was successfully synthesized and characterized with XRD, SEM+EDS and UV-Vis spectrophotometry. The uniformly distributed copper on the TiO 2 surface corresponds to the binding on high-affinity oxygen-rich sites, as proposed with DFT calculations. The photocatalytic degradation rate of ciprofloxacin was improved by about a factor of 1.5 compared to the bare non-modified TiO 2 . (4) Conclusions: The observed result was ascribed to the ability of adsorbed Cu to impede the agglomeration of TiO 2 and increase the active catalytic area, and bandgap narrowing predicted with DFT calculations.

Considering the enormous importance of protein turns as participants in various biological events, such as protein-protein interactions, great efforts have been made to develop their conformationally and proteolytically stable mimetics. Ferrocene-1,1'-diamine was previously shown to nucleate the stable turn structures in peptides prepared by conjugation with Ala ( III ) and Ala-Pro ( VI ). Here, we prepared the homochiral conjugates of ferrocene-1,1'-diamine with l-/d-Phe ( 32/35 ), l-/d-Val ( 33/36 ), and l-/d-Leu ( 34/37 ) to investigate (1) whether the organometallic template induces the turn structure upon conjugation with amino acids, and (2) whether the bulky or branched side chains of Phe, Val, and Leu affect hydrogen bonding. Detailed spectroscopic (IR, NMR, CD), X-ray, and DFT studies revealed the presence of two simultaneous 10-membered interstrand hydrogen bonds, i.e., two simultaneous β-turns in goal compounds. A preliminary biological evaluation of d-Leu conjugate 37 showed its modest potential to induce cell cycle arrest in the G0/G1 phase in the HeLa cell line but these results need further investigation.

Films based on carrageenan, alginate and poloxamer 407 have been formulated with the main aim to apply prepared formulations in wound healing process. The formulated films were loaded with diclofenac, an anti-inflammatory drug, as well as diclofenac and curcumin, as multipurpose drug, in order to enhance encapsulation and achieve controlled release of these low-bioavailability compounds. The obtained data demonstrated improved drug bioavailability (encapsulation efficiency higher than 90%), with high, cumulative in vitro release percentages (90.10% for diclofenac, 89.85% for curcumin and 95.61% for diclofenac in mixture-incorporated films). The results obtained using theoretical models suggested that curcumin establishes stronger, primarily dispersion interactions with carrier, in comparison with diclofenac. Curcumin and diclofenac-loaded films showed great antibacterial activity against Gram-positive bacteria strains ( Bacillus subtilis and Staphylococcus aureus , inhibition zone 16.67 and 13.67 mm, respectively), and in vitro and in vivo studies indicated that curcumin- and diclofenac-incorporated polymer films have great potential, as a new transdermal dressing, to heal wounds, because diclofenac can target the inflammatory phase and reduce pain, whereas curcumin can enhance and promote the wound healing process.

Mesoporous carriers are a convenient choice for the solidification of self-microemulsifying drug delivery systems (SMEDDS) designed to improve the solubility of poorly water-soluble drugs. They are known for high liquid load capacity and the ability to maintain characteristics of dry, free-flowing powders. Therefore, five different mesoporous carriers were used for the preparation of carvedilol-loaded SMEDDS granules by wet granulation methods-in paten (manually) and using a high-shear (HS) granulator. Granules with the highest SMEDDS content (63% and 66% of total granules mass, respectively) and suitable flow properties were obtained by Syloid ® 244FP and Neusilin ® US2. SMEDDS loaded granules produced by HS granulation showed superior flow characteristics compared to those obtained manually. All SMEDDS granules exhibited fast in vitro release, with 93% of carvedilol releasing from Syloid ® 244FP-based granules in 5 min. Upon compaction into self-microemulsifying tablets, suitable tablet hardness and very fast disintegration time were achieved, thus producing orodispersible tablets. The compaction slightly slowed down the carvedilol release rate; nevertheless, upon 1 h (at pH 1.2) or 4 h (at pH 6.8) of in vitro dissolution testing, the amount of released drug was comparable with granules, confirming the suitability of orodispersible tablets for the production of the SMEDDS loaded single unit oral dosage form.

Polyphenolic compounds are used for treating various diseases due to their antioxidant and anticancer properties. However, utilization of hydrophobic compounds is limited due to their low bioavailability. In order to achieve a greater application of hydrophobic bioactive compounds, hydrogel beads based on biopolymers can be used as carriers for their enhanced incorporation and controlled delivery. In this study, beads based on the biopolymers-κ-carrageenan, sodium alginate and poloxamer 407 were prepared for encapsulation of curcumin. The prepared beads were characterized using IR, SEM, TGA and DSC. The curcumin encapsulation efficiency in the developed beads was 95.74 ± 2.24%. The release kinetics of the curcumin was monitored in systems that simulate the oral delivery (pH 1.2 and 7.4) of curcumin. The drug release profiles of the prepared beads with curcumin indicated that the curcumin release was significantly increased compared with the dissolution of curcumin itself. The cumulative release of curcumin from the beads was achieved within 24 h, with a final release rate of 12.07% (gastric fluid) as well as 81.93% (intestinal fluid). Both the in vitro and in vivo studies showed that new hydrogel beads based on carbohydrates and poloxamer improved curcumin's bioavailability, and they can be used as powerful carriers for the oral delivery of different hydrophobic nutraceuticals.

Replacing a specified quantity of cement with Class F fly ash contributes to sustainable development and reducing the greenhouse effect. In order to use Class F fly ash in self-compacting concrete (SCC), a prediction model that will give a satisfactory accuracy value for the compressive strength of such concrete is required. This paper considers a number of machine learning models created on a dataset of 327 experimentally tested samples in order to create an optimal predictive model. The set of input variables for all models consists of seven input variables, among which six are constituent components of SCC, and the seventh model variable represents the age of the sample. Models based on regression trees (RTs), Gaussian process regression (GPR), support vector regression (SVR) and artificial neural networks (ANNs) are considered. The accuracy of individual models and ensemble models are analyzed. The research shows that the model with the highest accuracy is an ensemble of ANNs. This accuracy expressed through the mean absolute error (MAE) and correlation coefficient (R) criteria is 4.37 MPa and 0.96, respectively. This paper also compares the accuracy of individual prediction models and determines their accuracy. Compared to theindividual ANN model, the more transparent multi-gene genetic programming (MGPP) model and the individual regression tree (RT) model have comparable or better prediction accuracy. The accuracy of the MGGP and RT models expressed through the MAE and R criteria is 5.70 MPa and 0.93, and 6.64 MPa and 0.89, respectively.

With the increase in awareness of the importance of engagement in physical activities, high requirements have been placed on polymers intended for use in sports. A number of authors investigated the influence of aging factors on the performance of the polymer. Still, there is a lack of aging protocols that would be product-centered, especially when high performance is imperative. This paper presents a new approach to polymer aging and examines the change of the identified set of properties due to aging under different conditions, and the duration of each (topography, thickness, moisture management, elongation, and bursting force). The results of the testing revealed the increase in thickness due to exposure, especially to the sun-exposed materials. The ability of materials to elongate until the moment of rupture decreases due to exposure to the sun (strong relationship to the time of exposure; R 2 reaches 0.99) and the bursting force (up to 6.8%). Furthermore, results indicate the significantly impaired capacity of the polymer material to absorb moisture. The results of measurements indicated (derived) by spectroscopic studies, based on the ATR-FTIR (attenuated total reflectance) method, showed that there was no detectable influence of aging in the sun or shade on the chemical structure of polyester samples.

The concept of peptidomimetics is based on structural modifications of natural peptides that aim not only to mimic their 3D shape and biological function, but also to reduce their limitations. The peptidomimetic approach is used in medicinal chemistry to develop drug-like compounds that are more active and selective than natural peptides and have fewer side effects. One of the synthetic strategies for obtaining peptidomimetics involves mimicking peptide α-helices, β-sheets or turns. Turns are usually located on the protein surface where they interact with various receptors and are therefore involved in numerous biological events. Among the various synthetic tools for turn mimetic design reported so far, our group uses an approach based on the insertion of different ferrocene templates into the peptide backbone that both induce turn formation and reduce conformational flexibility. Here, we conjugated methyl 1'-aminoferrocene-carboxylate with homo- and heterochiral Pro-Ala dipeptides to investigate the turn formation potential and antiproliferative properties of the resulting peptidomimetics 2 - 5 . Detailed spectroscopic (IR, NMR, CD), X-ray and DFT studies showed that the heterochiral conjugates 2 and 3 were more suitable for the formation of β-turns. Cell viability study, clonogenic assay and cell death analysis showed the highest biological potential of homochiral peptide 4 .

This paper gives a comprehensive overview of the state-of-the-art machine learning methods that can be used for estimating self-compacting rubberized concrete (SCRC) compressive strength, including multilayered perceptron artificial neural network (MLP-ANN), ensembles of MLP-ANNs, regression tree ensembles (random forests, boosted and bagged regression trees), support vector regression (SVR) and Gaussian process regression (GPR). As a basis for the development of the forecast model, a database was obtained from an experimental study containing a total of 166 samples of SCRC. Ensembles of MLP-ANNs showed the best performance in forecasting with a mean absolute error (MAE) of 2.81 MPa and Pearson's linear correlation coefficient (R) of 0.96. The significantly simpler GPR model had almost the same accuracy criterion values as the most accurate model; furthermore, feature reduction is easy to combine with GPR using automatic relevance determination (ARD), leading to models with better performance and lower complexity.

Amino acids (AAs) attract attention for elucidating the role of proteins in biomineralization and the preparation of functionalized biomaterials. The influence that AAs exert on calcium phosphate (CaP) mineralization is still not completely understood, as contradictory results have been reported. In this paper, the influence of the addition of different classes of AAs, charged (L-aspartic acid, Asp; L-lysine, Lys), polar (L-asparagine, Asn; L-serine, Ser; L-tyrosine, Tyr), and non-polar (L-phenylalanine, Phe), on CaP growth in the presence of octacalcium phosphate (OCP) and calcium hydrogenphosphate dihydrate (DCPD) seeds was investigated. In control systems (without AAs), a calcium-deficient apatite (CaDHA) layer was formed on the surface of OCP, while a mixture of CaDHA and OCP in the form of spherical aggregates was formed on the surface of DCPD crystals. Charged and non-polar promoted, while polar AAs inhibited CaDHA formation on the OCP seeds. In the case of DCPD, Lys, Asp, and Phe promoted CaP formation, while the influence of other AAs was negligible. The most efficient promotor of precipitation in both cases was non-polar Phe. No significant influence of AAs on the composition and morphology of precipitates was observed. The obtained results are of interest for understanding biomineralization processes and additive controlled material synthesis.

Aims : The aim of this study was to compare the risk factors and prevalence of vascular calcification (VC) in pre-dialysis and hemodialysis (HD) patients with Balkan endemic nephropathy (BEN) or other kidney diseases (non-BEN). Materials and Methods : The study involved 115 patients, 32 pre-dialysis and 83 HD patients, separated into groups of BEN and non-BEN patients. In addition to interviews, objective examinations and laboratory analyses, VC was assessed using Adragao score. Results : Patients with BEN were significantly older in both groups, while pre-dialysis BEN patients had significantly lower systolic blood pressure, serum cholesterol and phosphorus levels, but higher urinary excretion of phosphorus than non-BEN patients. These differences were lost in HD groups. In pre-dialysis patients, prevalence of VC was lower in BEN than in non-BEN group and mean VC score differed significantly between them (2.8 (1.7) vs. 4.6 (1.8); p = 0.009). No significant difference in VC score was found between BEN and non-BEN patients on HD. Multivariate analysis showed that in pre-dialysis patients VC score >4 was associated with lower iPTH and higher serum cholesterol level, but in the HD group with higher serum triglyceride level and longer HD vintage. Conclusions : Lower prevalence of risk factors for VC in the BEN than non-BEN patients was found in pre-dialysis but not in HD group and this was reflected in the prevalence and severity of VC in the groups. Prevalence of VC and mean VC score were significantly lower in pre-dialysis BEN than in non-BEN patients but not for those on HD., Competing Interests: The authors declare no conflict of interest.

Our previous studies showed that alteration of dipeptides Y-Fca-Ala-OMe (III) into Y-Ala-Fca-OMe (IV) (Y=Ac, Boc; Fca=1'-aminoferrocene-1-carboxylic acid) significantly influenced their conformational space. The novel bioconjugates Y-Fca-Pro-OMe (1, Y=Ac; 2, Y=Boc) and Y-Pro-Fca-OMe (3, Y=Boc; 4, Y=Ac) have been prepared in order to investigate the influence of proline, a well-known turn-inducer, on the conformational properties of small organometallic peptides with an exchanged constituent amino acid sequences. For this purpose, peptides 1-4 were subjected to detailed spectroscopic analysis (IR, NMR, CD spectroscopy) in solution. The conformation of peptide 3 in the solid state was determined. Furthermore, the ability of the prepared conjugates to inhibit the growth of estrogen receptor-responsive MCF-7 mammary carcinoma cells and HeLa cervical carcinoma cells was tested.