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Growing interest in bacteriophage research and use, especially as an alternative treatment option for multidrug-resistant bacterial infection, requires rapid development of production methods and strengthening of bacteriophage activities. Bacteriophage adsorption to host cells initiates the process of infection. The rotating magnetic field (RMF) is a promising biotechnological method for process intensification, especially for the intensification of micromixing and mass transfer. This study evaluates the use of RMF to enhance the infection process by influencing bacteriophage adsorption rate. The RMF exposition decreased the t50 and t75 of bacteriophages T4 on Escherichia coli cells and vb_SauM_A phages on Staphylococcus aureus cells. The T4 phage adsorption rate increased from 3.13 × 10−9 mL × min−1 to 1.64 × 10−8 mL × min−1. The adsorption rate of vb_SauM_A phages exposed to RMF increased from 4.94 × 10−9 mL × min−1 to 7.34 × 10−9 mL × min−1. Additionally, the phage T4 zeta potential changed under RMF from −11.1 ± 0.49 mV to −7.66 ± 0.29 for unexposed and RMF-exposed bacteriophages, respectively.

Topical drug delivery in skin diseases provides a non-invasive, direct application of treatments to the affected area and avoids systemic toxicity. Quercetin is a natural polyphenol with documented activity to alleviate the symptoms of many skin diseases. The objective of this study was to prepare and assess the physicochemical properties of hydrogels made of sodium alginate (SA) and cellulose derivatives (methyl cellulose (MC) and carboxymethyl cellulose (CMC)), containing different concentrations of quercetin (0.4 and 0.7%). The physicochemical evaluation of the obtained hydrogels included organoleptic evaluation, texture analysis, spreadability, rheological properties, pH, and stability. Among the prepared formulations, MC-based gels had the highest viscosity, adhesiveness, cohesiveness, and stickiness. The results of this study indicate that MC-based hydrogels were superior to CMC- or SA-based gels in their ability to effectively deliver quercetin to the porcine skin ex vivo. The amount of quercetin retained in the skin after application of MC-based preparations containing higher concentrations of quercetin was 2.04-fold higher for CMC-based hydrogels and 2.6-fold higher for SA-based hydrogels.

The liver has a huge impact on the functioning of our body and the preservation of homeostasis. It is exposed to many serious diseases, which may lead to the chronic failure of this organ, which is becoming a global health problem today. Currently, the final form of treatment in patients with end-stage (acute and chronic) organ failure is transplantation. The proper function of transplanted organs depends on many cellular processes and immune and individual factors. An enormous role in the process of acceptance or rejection of a transplanted organ is attributed to, among others, the activation of the complement system. The aim of this study was the evaluation of the concentration of selected biomarkers’ complement system activation (C3a, C5a, and sC5b-9 (terminal complement complex)) in the serum of patients before and after liver transplantation (24 h, two weeks). The study was conducted on a group of 100 patients undergoing liver transplantation. There were no complications during surgery and no transplant rejection in any of the patients. All patients were discharged home 2–3 weeks after the surgery. The levels of all analyzed components of the complement system were measured using the ELISA method. Additionally, the correlations of the basic laboratory parameters—C-reactive protein (CRP), hemoglobin (Hb), total bilirubin, alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGTP), and albumin—with the parameters of the complement system (C3a, C5a, and sC5b-9) were determined. In our study, changes in the concentrations of all examined complement system components before and after liver transplantation were observed, with the lowest values before liver transplantation and the highest concentration two weeks after. The direct increase in components of the complement system (C3a, C5a, and sC5b-9) 24 h after transplantation likely affects liver damage after ischemia-reperfusion injury (IRI), while their increase two weeks after transplantation may contribute to transplant tolerance. Increasingly, attention is being paid to the role of C3a and CRP as biomarkers of damage and failure of various organs. From the point of view of liver transplantation, the most interesting correlation in our own research was found exactly between CRP and C3a, 24 h after the transplantation. This study shows that changes in complement activation biomarkers and the correlation with CRP in blood could be a prognostic signature of liver allograft survival or rejection.

Compounding formulations, including semi-solid medication forms, must meet criteria related to specific stability and quality, during a period of their use. In suspension-type ointments, one of the criteria for assessment of their correct manufacturing is particle size, which in the compounding preparation cannot exceed 90 µm. An appropriate level of particle disintegration can be achieved via a selection of technological parameters and qualitatively compatible excipients. In this study, benzocaine ointments were prepared using a levigation process. The time of its application on the particle size of API in suspension ointments was evaluated. In parallel, the effect of mixing parameters and the co-solvent used on the precipitation of active substance crystals in emulsion ointments during the storage of these formulations for 28 days was investigated. Forty suspension and emulsion ointments were prepared using selected ointment bases: Pentravan®, Lekobaza, Lekobaza LUX, Eucerin Ointment I, Nourivan™ Antiox, Fitalite™, containing 2% benzocaine. Based on the results of the stability test, four formulations were selected to study the release kinetics of benzocaine in vitro. These formulations were characterized by the rate of release consistent with the Higuchi model, and the fastest rate of release occurred from the Eucerin-based emulsion ointment.

Growth hormone (somatotropin—STH) deficiency therapy requires daily injections of recombinant human growth hormone. The FDA approved treatment with STH with one dose per week for the first time in 2021. However, injectable drug application is accompanied by numerous inconveniences. Therefore, an attempt was made to formulate a less invasive STH formulation for topical application to the skin. A substrate was prepared based on a polymer, methylcellulose (MC), into which STH was introduced at a concentration of 1 mg/g. Simultaneously, formulations were made with STH, to which albumin (ALB) was added at different concentrations: 0.1%, 0.2% and 0.5%. A test of the degree of STH permeation was carried out, as well as the effect of ALB on STH permeation parameters. Selected rheological properties of the formulations obtained were investigated. A test of STH permeation in simulated in vivo conditions through porcine skin indicated a relatively good bioavailability of over 80% and confirmed the effectiveness of MC as a carrier for growth hormone. ALB prolonged the STH penetration rate and increased the penetration degree of STH to 93%. The hydrogels obtained were found to be typical shear-thinning, thixotropic fluids.

Hydrodynamic conditions are critical in bioprocessing because they influence oxygen availability for cultured cells. Processes in typical laboratory bioreactors need optimization of these conditions using mixing and aeration control to obtain high production of the desired bioproduct. It could be done by experiments supported by computational fluid dynamics (CFD) modeling. In this work, we characterized parameters such as mixing time, power consumption and mass transfer in a 2 L bioreactor. Based on the obtained results, we chose a set of nine process parameters to test the hydrodynamic impact on a selected bioprocess (mixing in the range of 0–160 rpm and aeration in the range of 0–250 ccm). Therefore, we conducted experiments with P. aeruginosa culture and assessed how various hydrodynamic conditions influenced biomass, pyocyanin and rhamnolipid production. We found that a relatively high mass transfer of oxygen (kLa = 0.0013 s−1) connected with intensive mixing (160 rpm) leads to the highest output of pyocyanin production. In contrast, rhamnolipid production reached maximal efficiency under moderate oxygen mass transfer (kLa = 0.0005 s−1) and less intense mixing (in the range of 0–60 rpm). The results indicate that manipulating hydrodynamics inside the bioreactor allows control of the process and may lead to a change in the metabolites produced by bacterial cells.

Selenium in the human body exhibits strong antioxidant and immunomodulatory properties. This bio-element is found in the active centers of antioxidant enzymes, which participate in the elimination of damage caused by free oxygen radicals. It enters into the composition of some proteins that build cell membranes, and performs stabilizing functions. Its involvement in catalyzing redox reactions helps reduce oxidative stress and potentially minimize ischemia–reperfusion damage in the kidney during ischemia. The aim of this study was to determine whether supplementation of preservative fluid with selenium in the presence of the antioxidant prolactin affects the levels of selected biochemical indices in homogenates of isolated porcine kidneys. The work is part of a series of our team studies to develop the optimal fluid composition for organ perfusion and preservation. Biolasol preservation fluid was modified by adding Se4+ (1 µg/L) and prolactin (0.1 µg/L). The study was conducted on 30 isolated kidneys of Polish Large White pigs. The kidneys were randomly divided into 3 groups (n = 10 in each) and were washed with preservative fluids: Biolasol control kidneys (C), Biolasol+Se (A1), Biolasol+Se+PRL (A2). After 48 h of preservation and perfusion, kidney sections were excised. Selected biochemical markers were determined in the tissue homogenates: protein and creatinine concentration. The study was performed in accordance with the recommendations of the II Local Ethics Commission for Animal Experiments in Cracow, Poland (number 1046/2013), and in accordance with the European Union Directive (EU guideline 93/119/EC). Supplementation of Biolasol solution with selenium and prolactin caused a statistically significant reduction in protein and creatinine levels compared to the control group in homogenates of isolated pig kidneys. Protein concentrations were: 2.5 ± 0.1 mg/g (group C) vs. 0.9 ± 0.2 mg/g (group A2) (p < 0.05), and creatinine concentrations were: 2.5 ± 0.1 mg/g (group C) vs. 1.9 ± 0.2 mg/g (group A2) (p < 0.05). In contrast, the use of selenium alone (without PRL shielding) resulted in a statistical increase in marker concentrations. Protein concentrations were 20% higher compared to Biolasol (p < 0.05), and creatinine concentrations were 16% higher compared to Biolasol (p < 0.05). Presumably, there was an accumulation of selenium in the organ, exacerbating the resulting damage. Selenium and prolactin added to Biolasol fluid show protective effects on nephrons. Selenium (IV) as a component of Biolasol solution adversely affects renal protection during ischemia.

Warm and humid climatic conditions coupled with poor agricultural practices in sub-Saharan Africa favor the contamination of food and feed by Aspergillus flavus and Fusarium verticillioides fungi, which subsequently may produce aflatoxins (AFs) and fumonisins (FBs), respectively. The growth of fungi and the production of mycotoxins are influenced by physical (temperature, pH, water activity, light and aeration), nutritional, and biological factors. This study aimed at optimizing the conditions for the laboratory production of large quantities of AFs and FBs for use in the animal experiments. A. flavus and F. verticillioides strains, previously isolated from maize in Kenya, were used. Levels of AFB1 and total FBs (FB1, FB2, and FB3) in different growth substrates were screened using ELISA methods. Maize kernels inoculated with three different strains of A. flavus simultaneously and incubated at 29 °C for 21 days had the highest AFB1 level of 12,550 ± 3397 μg/kg of substrate. The highest level of total FBs (386,533 ± 153,302 μg/kg of substrate) was detected in cracked maize inoculated with three different strains of F. verticillioides and incubated for 21 days at temperatures of 22–25 °C in a growth chamber fitted with yellow light. These two methods are recommended for the mass production of AFB1 and FBs for animal feeding trials.

Oomycetes are pathogens of plants and animals, which cause billions of dollars of global losses to the agriculture, aquaculture and forestry sectors each year. These organisms superficially resemble fungi, with an archetype being Phytophthora infestans, the cause of late blight of tomatoes and potatoes. Comparison of the physiology of oomycetes with that of other organisms, such as plants and animals, may provide new routes to selectively combat these pathogens. In most eukaryotes, myo-inositol 1,4,5 trisphosphate is a key second messenger that links extracellular stimuli to increases in cytoplasmic Ca2+, to regulate cellular activities. In the work presented in this study, investigation of the molecular components of myo-inositol 1,4,5 trisphosphate signaling in oomycetes has unveiled similarities and differences with that in other eukaryotes. Most striking is that several oomycete species lack detectable phosphoinositide-selective phospholipase C homologues, the enzyme family that generates this second messenger, but still possess relatives of myo-inositol 1,4,5 trisphosphate-gated Ca2+-channels.

Three carriers of the solute carrier family SLC10 have been functionally characterized so far. Na+/taurocholate cotransporting polypeptide NTCP is a hepatic bile acid transporter and the cellular entry receptor for the hepatitis B and D viruses. Its intestinal counterpart, apical sodium-dependent bile acid transporter ASBT, is responsible for the reabsorption of bile acids from the intestinal lumen. In addition, sodium-dependent organic anion transporter SOAT specifically transports sulfated steroid hormones, but not bile acids. All three carriers show high sequence homology, but significant differences in substrate recognition that makes a systematic structure-activity comparison attractive in order to define the protein domains involved in substrate binding and transport. By using stably transfected NTCP-, ASBT-, and SOAT-HEK293 cells, systematic comparative transport and inhibition experiments were performed with more than 20 bile acid and steroid substrates as well as different inhibitors. Taurolithocholic acid (TLC) was identified as the first common substrate of NTCP, ASBT and SOAT with Km values of 18.4, 5.9, and 19.3 µM, respectively. In contrast, lithocholic acid was the only bile acid that was not transported by any of these carriers. Troglitazone, BSP and erythrosine B were identified as pan-SLC10 inhibitors, whereas cyclosporine A, irbesartan, ginkgolic acid 17:1, and betulinic acid only inhibited NTCP and SOAT, but not ASBT. The HBV/HDV-derived myr-preS1 peptide showed equipotent inhibition of the NTCP-mediated substrate transport of taurocholic acid (TC), dehydroepiandrosterone sulfate (DHEAS), and TLC with IC50 values of 182 nM, 167 nM, and 316 nM, respectively. In contrast, TLC was more potent to inhibit myr-preS1 peptide binding to NTCP with IC50 of 4.3 µM compared to TC (IC50 = 70.4 µM) and DHEAS (IC50 = 52.0 µM). Based on the data of the present study, we propose several overlapping, but differently active binding sites for substrates and inhibitors in the carriers NTCP, ASBT, SOAT.

Objective The authors carried out a systematic review and a meta-analysis on smoking cessation interventions on health -care workers to clarify the state of the art interventions and to identify the best one. Materials and Methods This review was registered with PROSPERO: CRD42019130117. The databases PubMed, Scopus, Web of Science and CINAHL were searched until December 2018. Quality of all studies included in the systematic review was assessed according to the Newcastle-Ottawa Scale (NOS) on cohort or cross-sectional studies and to the Cochrane Risk of Bias Tool for Randomized Controlled Trials. Meta-analysis and meta-regression analyses were also carried out for cohort studies (quasi-experimental or a before-after studies design) and clinical trials. Results Twenty–four studies have been included in the analysis: four before-after, 13 cross-sectional, three quasi-experimental studies and four clinical trials. Articles were heterogeneous (P for homogeneity

In this paper, we assess the pressure between the overdenture located in the mandible and supported by a bar retained on two implants and the prosthodontic area. For testing, a model of an edentulous mandible was created using a mold by FRASACO with two implants and a “rider” bar inserted. A complete mandibular denture with polypropylene matrices was made. Three types of matrices of various stiffness were applied. The mandible and overdenture geometry was mapped using a digital image obtained with a Steinbichler Comet L3D 3D scanner. Finite element method calculations were performed in the Abaqus FEA software. The results demonstrate that the maximum contact pressure is observed when the loads are associated with canines. A critical case for the lower posterior is chewing performed by the molars. The pressure zone is the largest for POM-1 with Young’s modulus of 1.5 GPa and is reduced by 5.0% and 7.8% for POM-2 (E = 2.5 GPa) and POM-3 (E = 3.5 GPa), respectively. The stress distribution under the prosthesis mostly depends on the region loaded onto it. The applied load produces a slight contact pressure between the denture and the prosthodontic area in the anterior zone. A change in polypropylene matrix stiffness does not affect contact pressures.

Diseases caused by trypanosomatids (Sleeping sickness, Chagas disease, and leishmaniasis) are a serious public health concern in low-income endemic countries. These diseases are produced by single-celled parasites with a diploid genome (although aneuploidy is frequent) organized in pairs of non-condensable chromosomes. To explain the way they reproduce through the analysis of natural populations, the theory of strict clonal propagation of these microorganisms was taken as a rule at the beginning of the studies, since it partially justified their genomic stability. However, numerous experimental works provide evidence of sexual reproduction, thus explaining certain naturally occurring events that link the number of meiosis per mitosis and the frequency of mating. Recent techniques have demonstrated genetic exchange between individuals of the same species under laboratory conditions, as well as the expression of meiosis specific genes. The current debate focuses on the frequency of genomic recombination events and its impact on the natural parasite population structure. This paper reviews the results and techniques used to demonstrate the existence of sex in trypanosomatids, the inheritance of kinetoplast DNA (maxi- and minicircles), the impact of genetic exchange in these parasites, and how it can contribute to the phenotypic diversity of natural populations.

The cultivation of bacteria sets a ground for studying biological processes in many scientific disciplines. The development of the bacterial population is commonly described with three factors that can be used to evaluate culture conditions. However, selecting only one of them for the optimization protocol is rather problematic and may lead to unintended errors. Therefore, we proposed a novel mathematical approach to obtain a single factor that could be used as the objective function to evaluate the whole growth dynamic and support the optimization of the biomass production process. The sigmoidal-shape curve, which is the commonly used function to plot the amount of biomass versus time, was the base for the mathematical analysis. The key process parameters, such as maximal specific growth rate and lag-phase duration were established with the use of mathematical coefficients of the model curve and combined to create the single growth parameter. Moreover, this parameter was used for the exemplary optimization of the cultivation conditions of Klebsiella pneumoniae that was cultured to be further used in the production of lytic bacteriophages. The proposed growth parameter was successfully validated and used to calculate the optimal process temperature of the selected bacterial strain. The obtained results indicated that the proposed mathematical approach could be effortlessly adapted for a precise evaluation of growth curves.

The human microbiome has been proven to contribute to the human condition, both in health and in disease. The metagenomic approach based on next-generation sequencing has challenged the dogma of urine sterility. The human urobiome consists of bacteria and eukaryotic viruses as well as bacteriophages, which potentially represent the key factor. There have been several significant findings with respect to the urobiome in the context of urological disorders. Still, the research on the urobiome in chronic kidney disease and kidney transplantation remains underrepresented, as does research on the role of the virome in the urinary microbiota. In this review, we present recent findings on the urobiome with a particular emphasis on chronic kidney disease and post-kidney transplantation status. Challenges and opportunities arising from the research on the human urobiome will also be discussed.

The development of antimicrobial resistance has become a global concern. One approach to overcome the problem of drug resistance is the application of bacteriophages. This study aimed at characterizing three phages isolated from sewage, which show lytic activity against clinical isolates of multidrug-resistant Staphylococcus aureus. Morphology, genetics and biological properties, including host range, adsorption rate, latent time, phage burst size and lysis profiles, were studied in all three phages. As analyzed by transmission electron microscopy (TEM), phages vB_SauM-A, vB_SauM-C, vB_SauM-D have a myovirion morphology. One of the tested phages, vB_SauM-A, has relatively rapid adsorption (86% in 17.5 min), short latent period (25 min) and extremely large burst size (~500 plaque-forming units (PFU) per infected cell). The genomic analysis revealed that vB_SauM-A, vB_SauM-C, vB_SauM-D possess large genomes (vB_SauM-A 139,031 bp, vB_SauM-C 140,086 bp, vB_SauM-D 139,088 bp) with low G+C content (~30.4%) and are very closely related to the phage K (95−97% similarity). The isolated bacteriophages demonstrate broad host range against MDR S. aureus strains, high lytic activity corresponding to strictly virulent life cycle, suggesting their potential to treat S. aureus infections.

A medida que las áreas de vegetación natural en los neotrópicos estén siendo reducidas a remanentes aislados, la importancia de la vegetación secundaria para la conservación de especies aumentará. Por lo tanto, debe determinarse el valor de los hábitats modificados o creados por el hombre para la conservación de especies dependientes de hábitats originales. En este estudio, evaluamos el valor para la conservación de tres hábitats asociados a la ganadería (bosque ribereño, cerco vivo y pastizal) para las aves típicas de bosque tropical en la región caribeña de Guatemala. Estudiamos las comunidades de aves de cinco sitios de bosque tropical bajo y bosque ribereño (río), tres sitios de cerco vivo y cuatro de pastizales, en cinco fincas ganaderas de la región, y comparamos los cuatro hábitats en función de los siguientes parámetros: número de especies, número de individuos, composición de especies, e índice de importancia. Una serie de 10 puntos de conteo se evaluó (seis repeticiones de cada serie) en cada hábitat, durante abril y mayo de 1998 y 1999. Aunque el número de especies fue similar en bosque, río y cerco vivo (111, 96 y 94 especies, respectivamente), y el río y cerco vivo superaron al bosque en el número de individuos (80 y 72, comparado a 56 individuos), el río y cerco vivo tuvieron números de especies e individuos de residentes de interior de bosque significativamente menores a los del bosque (56, 21 y 15 especies y 61, 19 y 8 individuos en bosque, río y cerco, respectivamente). El río y cerco vivo no se diferenciaron en el número de especies e individuos residentes de borde de bosque, pero la composición de las comunidades de este grupo de especies fue significativamente distinta entre estos dos hábitats y el bosque. Las especies de borde que fueron relativamente abundantes en bosque tuvieron abundancias muy bajas en los hábitats modificados, y aquellas que fueron abundantes en río y cerco vivo estaban prácticamente ausentes en el bosque tropical y fueron generalistas. Con respecto a las especies migratorias, tanto el río como el cerco vivo resultaron ser muy importantes para éstas, y el río incluso fue más importante que el bosque tropical. Concluimos que estos hábitats modificados tienen muy poco valor de conservación para las especies residentes típicas de bosque tropical, pero resultan ser muy importantes para las especies migratorias, particularmente para aquellas con hábitos arbóreos. Destacamos la importancia de evaluar la importancia de de los hábitas modificados particularmente en función de la composición de especies, y en función de las especies para las cuáles se desea evaluar la importancia de los hábitats modificados, en nuestro caso, para las especies típicas de bosque tropical.Modified-habitat use by tropical forest-dependent birds in the Caribbean region of Guatemala. As natural areas are reduced into isolated remnants, the importance of secondary habitats for species conservation will increase. Consequently, the conservation value of human-modified or created secondary habitats must be determined. in this study, we evaluated the conservation potential of three habitats associated to cattle ranching (riparian forest, live fence, and pasture) for tropical forest birds in the Caribbean region of Guatemala. We studied the bird communities of five tropical forest and riparian forest (henceforth river) sites, three live fence sites and four pasture sites, in five cattle ranches in the region, and compared the four habitats based on the following parameters: species richness, number of individuals, species composition and an index of conservation importance. A 10-point series was sampled (six repetitions of each series) in each habitat site using the point-count method, in march and april of 1998 and 1999. Although forest, river and live fence had similar mean species numbers, considering all species (111, 96 and 94 species, respectively), and river and live fence surpassed the forest in mean number of individuals (80 and 72 compared to 56 individuals), river and live fence had significantly fewer mean numbers of interior-forest resident species and individuals (56, 21 and 15 species, and 61, 19 and eight individuals in forest, river and live fence, respectively). River and live fence, when compared to forest, had no significant differences in the number of resident forest-edge species and individuals, but their edge-species composition was significantly different from forest. Those resident edge species that were relatively abundant in forest had very low abundances in the modified habitats, and those that were abundant in river and live fence were rare or absent in forest sites. With respect to migratory species, both river and live fence were very important, and the river was more important than forest, according to the conservation importance index. We conclude that these modified habitats have very little value for tropical forest-dependent resident species, but are extremely important for migratory species, particularly those of arboreal habits. We also stress that the conservation importance of alternative habitats should be based on species composition, as opposed to species richness and abundance, and defined as a function of species of particular conservation importance, in our locality, those dependent of tropical lowland forest. Rev. Biol. Trop. 57 (1-2): 401-419. Epub 2009 June 30.