ABSTRACT
While phages hold promise as an antibiotic alternative, they encounter significant challenges in combating bacterial infections, primarily due to the emergence of phage-resistant bacteria. Bacterial defence mechanisms like superinfection exclusion, CRISPR, and restriction-modification systems can hinder phage effectiveness. Innovative strategies, such as combining different phages into cocktails, have been explored to address these challenges. This review delves into these defence mechanisms and their impact at each stage of the infection cycle, their challenges, and the strategies phages have developed to counteract them. Additionally, we examine the role of phage cocktails in the evolving landscape of antibacterial treatments and discuss recent studies that highlight the effectiveness of diverse phage cocktails in targeting essential bacterial receptors and combating resistant strains.
ABSTRACT
Vibrio toranzoniae is a marine bacterium belonging to the Splendidus clade that was originally isolated from healthy clams in Galicia (NW Spain). Its isolation from different hosts and seawater indicated two lifestyles and wide geographical distribution. The aim of the present study was to determine the differences at the genomic level among six strains (4 isolated from clam and 2 from seawater) and to determine their phylogeny. For this purpose, whole genomes of the six strains were sequenced by different technologies including Illumina and PacBio, and the resulting sequences were corrected. Genomes were annotated and compared using different online tools. Furthermore, the study of core- and pan-genomes were examined, and the phylogeny was inferred. The content of the core genome ranged from 2953 to 2766 genes and that of the pangenome ranged from 6278 to 6132, depending on the tool used. Although the strains shared certain homology, with DDH values ranging from 77.10 to 82.30 and values of OrthoANI values higher than 97%, some differences were found related to motility, capsule synthesis, iron acquisition systems or mobile genetic elements. Phylogenetic analysis of the core genome did not reveal a differentiation of the strains according to their lifestyle (commensal or free-living), but that of the pangenome indicated certain geographical isolation in the same growing area. This study led to the reclassification of some isolates formerly described as V. toranzoniae and demonstrated the importance of cured deposited sequences to proper phylogenetic assignment.
ABSTRACT
Vibrio toranzoniae is a marine bacterium belonging to the Splendidus clade, originally isolated from healthy clams in Galicia (NW Spain). Its isolation from different hosts and seawater indicated two lifestyles and wide geographical distribution. The aim of the present study was to determine the differences at genome level among strains, as well as to determine their phylogeny. For this purpose, whole genomes were sequenced by different technologies and the resulting sequences corrected. Genomes were annotated and compared with different online tools. Furthermore, the study of core and pan genome was examined, and the phylogeny was inferred. The content of the core genome ranged from 2,953 to 2,766 genes and that of the pangenome from 6,278 to 6,132, depending on the tool used. The comparison revealed that although the strains shared certain homology, with DDH values ranging from 77.10 to 82.30 and values of OrthoANI higher than 97%,notable differences were found related to motility, capsule synthesis, iron acquisition system or mobile genetic elements. The phylogenetic analysis of the core genome did not reveal a differentiation of the strains according to their lifestyle, but that of the pangenome pointed out certain geographical isolation in the same growing area. The study led to a reclassification of some isolates formerly described as V. toranzoniae and manifested the importance of cured deposited sequences to proper phylogenetic assignment.
ABSTRACT
Varroa mites, scientifically identified as Varroa destructor, pose a significant threat to beekeeping and cause one of the most destructive diseases affecting honey bee populations. These parasites attach to bees, feeding on their fat tissue, weakening their immune systems, reducing their lifespans, and even causing colony collapse. They also feed during the pre-imaginal stages of the honey bee in brood cells. Given the critical role of honey bees in pollination and the global food supply, controlling Varroa mites is imperative. One of the most common methods used to evaluate the level of Varroa mite infestation in a bee colony is to count all the mites that fall onto sticky boards placed at the bottom of a colony. However, this is usually a manual process that takes a considerable amount of time. This work proposes a deep learning approach for locating and counting Varroa mites using images of the sticky boards taken by smartphone cameras. To this end, a new realistic dataset has been built: it includes images containing numerous artifacts and blurred parts, which makes the task challenging. After testing various architectures (mainly based on two-stage detectors with feature pyramid networks), combination of hyperparameters and some image enhancement techniques, we have obtained a system that achieves a mean average precision (mAP) metric of 0.9073 on the validation set.
Subject(s)
Deep Learning , Software , Varroidae , Animals , Varroidae/pathogenicity , Varroidae/physiology , Bees/parasitology , Bees/physiology , Mite Infestations/parasitology , Beekeeping/methods , Image Processing, Computer-Assisted/methodsABSTRACT
Urinary tract infections (UTIs) caused by resistant Klebsiella pneumoniae can lead to severe clinical complications and even death. An alternative treatment option for infected patients is using bacteriophages. In the present study, we isolated phage VB_KPM_KP1LMA (KP1LMA) from sewage water using a K. pneumoniae strain as a host. Whole-genome analysis indicated that the genome was a double-stranded linear 176,096-bp long DNA molecule with 41.8% GC content and did not contain virulence or antibiotic resistance genes. The inactivation potential of phage KP1LMA was assessed in broth at an MOI of 1 and 10, and a maximum inactivation of 4.9 and 5.4 log CFU/mL, respectively, was observed after 9 h. The efficacy at an MOI of 10 was also assessed in urine to evaluate the phage's performance in an acidic environment. A maximum inactivation of 3.8 log CFU/mL was observed after 9 h. The results suggest that phage KP1LMA could potentially control a UTI caused by this strain of K. pneumoniae, indicating that the same procedure can be used to control UTIs caused by other strains if new specific phages are isolated. Although phage KP1LMA has a narrow host range, in the future, efforts can be made to expand its spectrum of activity and also to combine this phage with others, potentially enabling its use against other K. pneumoniae strains involved in UTIs.
ABSTRACT
The formation of a stable complex between proteins lies at the core of a wide variety of biological processes and has been the focus of countless experiments. The huge amount of information contained in the protein structural interactome in the Protein Data Bank can now be used to characterise and classify the existing biological interfaces. We here introduce ARCTIC-3D, a fast and user-friendly data mining and clustering software to retrieve data and rationalise the interface information associated with the protein input data. We demonstrate its use by various examples ranging from showing the increased interaction complexity of eukaryotic proteins, 20% of which on average have more than 3 different interfaces compared to only 10% for prokaryotes, to associating different functions to different interfaces. In the context of modelling biomolecular assemblies, we introduce the concept of "recognition entropy", related to the number of possible interfaces of the components of a protein-protein complex, which we demonstrate to correlate with the modelling difficulty in classical docking approaches. The identified interface clusters can also be used to generate various combinations of interface-specific restraints for integrative modelling. The ARCTIC-3D software is freely available at github.com/haddocking/arctic3d and can be accessed as a web-service at wenmr.science.uu.nl/arctic3d.
Subject(s)
Data Mining , Prokaryotic Cells , Cluster Analysis , Databases, Protein , EntropyABSTRACT
Prisons are high-risk settings for infectious disease transmission, due to their enclosed and semi-enclosed environments. The proximity between prisoners and staff, and the diversity of prisons reduces the effectiveness of non-pharmaceutical interventions, such as social distancing. Therefore, alternative health monitoring methods, such as wastewater-based epidemiology (WBE), are needed to track pathogens, including SARS-CoV-2. This pilot study assessed WBE to quantify SARS-CoV-2 prevalence in prison wastewater to determine its utility within a health protection system for residents. The study analysed 266 samples from six prisons in England over a 12-week period for nucleoprotein 1 (N1 gene) and envelope protein (E gene) using quantitative reverse transcriptase-polymerase chain reaction. Both gene assays successfully detected SARS-CoV-2 fragments in wastewater samples, with both genes significantly correlating with COVID-19 case numbers across the prisons (p < 0.01). However, in 25% of the SARS-positive samples, only one gene target was detected, suggesting that both genes be used to reduce false-negative results. No significant differences were observed between 14- and 2-h composite samples, although 2-h samples showed greater signal variance. Population normalisation did not improve correlations between the N1 and E genes and COVID-19 case data. Overall, WBE shows considerable promise for health protection in prison settings.
Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Prisons , Wastewater , COVID-19/epidemiology , Pilot Projects , United Kingdom/epidemiologyABSTRACT
AIM: To compare total metabolic tumour volume (tMTV), calculated using two artificial intelligence (AI)-based tools, with manual segmentation by specialists as the reference. METHODS: Forty-eight consecutive Hodgkin lymphoma (HL) patients staged with [18F] fluorodeoxyglucose positron emission tomography/computed tomography were included. The median age was 35 years (range: 7-75), 46% female. The tMTV was automatically measured using the AI-based tools positron emission tomography assisted reporting system (PARS) (from Siemens) and RECOMIA (recomia.org) without any manual adjustments. A group of eight nuclear medicine specialists manually segmented lesions for tMTV calculations; each patient was independently segmented by two specialists. RESULTS: The median of the manual tMTV was 146 cm3 (interquartile range [IQR]: 79-568 cm3) and the median difference between two tMTV values segmented by different specialists for the same patient was 26 cm3 (IQR: 10-86 cm3). In 22 of the 48 patients, the manual tMTV value was closer to the RECOMIA tMTV value than to the manual tMTV value segmented by the second specialist. In 11 of the remaining 26 patients, the difference between the RECOMIA tMTV and the manual tMTV was small (<26 cm3, which was the median difference between two manual tMTV values from the same patient). The corresponding numbers for PARS were 18 and 10 patients, respectively. CONCLUSION: The results of this study indicate that RECOMIA and Siemens PARS AI tools could be used without any major manual adjustments in 69% (33/48) and 58% (28/48) of HL patients, respectively. This demonstrates the feasibility of using AI tools to support physicians measuring tMTV for assessment of prognosis in clinical practice.
Subject(s)
Hodgkin Disease , Humans , Female , Adult , Male , Hodgkin Disease/diagnostic imaging , Hodgkin Disease/therapy , Artificial Intelligence , Tumor Burden , Prognosis , Fluorodeoxyglucose F18/metabolism , Positron Emission Tomography Computed Tomography/methods , Retrospective StudiesABSTRACT
The indiscriminate use of allopathic drugs has selected resistant bacterial and fungal populations which represents a severe public health problem worldwide. On the other hand, plants are in a prominent position due to the capability to synthesize structurally complex bioactive metabolites that can be an alternative to resistant microorganisms' control. In this work, we evaluated the chemical composition and the antimicrobial, antioxidant, and cytotoxic potential of the fractionated extract of C. savannarum in ethyl acetate. The extract of C. savannarum was divided into 12 fractions that were submitted to phytochemical screening, minimum inhibitory concentration (MIC), reduction of 1,1-diphenyl-2-picrylhydrazine (DPPH), and hemolytic activity of sheep erythrocytes assays. During the investigation, all extract fractions presented alkaloids, triterpenoids, steroids, and phenolic compounds in qualitative analyses, while in the quantitative evaluation, we observed the presence of both phenols and flavonoids in these fractions. Among the fraction, the highest phenolic content was observed in the Cs23-24 fraction (2.480 mg EAG/g), while the Cs31-34 fractions presented the highest amount of flavonoid (182.25 µg EQ/100 mg). Nine of the 12 fractions of the moss species' extract showed antimicrobial action Against Gram-positive bacteria: Bacillus cereus, Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis; Gram-negative bacteria: Pseudomonas aeruginosa; and also antifungal activity against Candida albicans and Candida glabata. The cytotoxic assay demonstrated that the tested fractions did not induce hemolysis at concentrations 10 and 100(µG/ML). In the antioxidant evaluation, the Cs55-69 fractions were the ones that presented the highest scavenging activity (57, 0%) followed by the Cs45-54 fraction (42.7%). Overall, the evaluation of the biological potential of the fractionated extracts of Campylopus savannarum showed promising data, in the search for natural antimicrobial compounds.
Subject(s)
Anti-Infective Agents , Antioxidants , Animals , Sheep , Antioxidants/pharmacology , Antioxidants/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Antifungal Agents , Bacteria , Flavonoids/analysisABSTRACT
The increasing interest in innovative solutions for addressing bone defects has driven research into the use of Bioactive Mesoporous Glasses (MBGs). These materials, distinguished by their well-ordered mesoporous structure, possess the capability to accommodate plant extracts with well-established osteogenic properties, including bovine lactoferrin (bLF), as part of their 3D scaffold composition. This harmonizes seamlessly with the ongoing advancements in the field of biomedicine. In this study, we fabricated 3D scaffolds utilizing MBGs loaded with extracts from parsley leaves (PL) and embryogenic cultures (EC), rich in bioactive compounds such as apigenin and kaempferol, which hold potential benefits for bone metabolism. Gelatin Methacryloyl (GelMa) served as the polymer, and bLF was included in the formulation. Cytocompatibility, Runx2 gene expression, ALP enzyme activity, and biomineralization were assessed in preosteoblastic MC3T3-E1 cell cultures. MBGs effectively integrated PL and EC extracts with loadings between 22.6 ± 0.1 and 43.6 ± 0.3 µM for PL and 26.3 ± 0.3 and 46.8 ± 0.4 µM for EC, ensuring cell viability through a release percentage between 28.3% and 59.9%. The incorporation of bLF in the 3D scaffold formulation showed significant differences compared to the control in all assays, even at concentrations below 0.2 µM. Combinations, especially PL + bLF at 0.19 µM, demonstrated additive potential, with superior biomineralization compared to EC. In summary, this study highlights the effectiveness of MBGs in incorporating PL and EC extracts, along with bLF, into 3D scaffolds. The results underscore cytocompatibility, osteogenic activity, and biomineralization, offering exciting potential for future in vivo applications.
Subject(s)
Lactoferrin , Petroselinum , Lactoferrin/pharmacology , Lactoferrin/metabolism , Osteoblasts/metabolism , Cell Culture TechniquesABSTRACT
Introducción: la promoción de hábitos de vida saludables es una práctica habitual entre los pediatras. Dentro de estos se encuentra la promoción de la lectura, que entraña numerosos beneficios para la infancia: estimula la actividad cerebral y su reserva cognitiva, aumenta la concentración y el desarrollo del lenguaje y permite trabajar las emociones. El objetivo de este estudio es conocer la realidad de la práctica de la promoción de la lectura desde las consultas de Pediatría, así como su relación con la vocación pediátrica (clínica, preventiva y social) y los entornos profesionales (residencia, hospital y Atención Primaria). Material y métodos: estudio transversal, descriptivo de ámbito nacional, mediante encuesta en línea a residentes de Pediatría, pediatras hospitalarios/as y de Atención Primaria llevado a cabo en marzo de 2022. Resultados: participaron 326 pediatras, un 16,8% hospitalarios/as, un 69,8% de Atención Primaria y 13,4% residentes de Pediatría. El 18,8% seleccionaron la vocación preventiva, el 60,8%, la clínica y el 20,5%, la social. Junto con una descripción detallada del tipo de actividades de promoción de la lectura que se realizan en nuestro país, los resultados mostraron, en primer lugar, que la vocación médica se relacionó con su mayor o menor realización (χ2(2) = 13,11, p <0,001), siendo los pediatras con vocación social los que informaron llevarlas a cabo en un mayor porcentaje. En segundo lugar, también el ámbito de trabajo apareció como un condicionante para la realización de estas actividades (χ2(2) = 19,0, p <0,001), que se llevan a cabo más frecuentemente en las consultas de Atención Primaria. Conclusiones: las actividades de promoción de la lectura son realizadas mayormente por los profesionales de Atención Primaria, en el marco de otras actividades de promoción de la salud, vinculadas principalmente con su mayor vocación por la Pediatría social. (AU)
Introduction: healthy lifestyle promotion is a common practice among paediatricians. Reading promotion is included in that practice. It has numerous benefits for children: it stimulates brain activity and cognitive reserve, improves concentration and language development and helps develop emotional skills.The aim of our study was to assess the implementation of reading promotion activities in real-world paediatric care practice, as well as its association with the underlying vocation for paediatrics (clinical, preventive or social) and the care setting (residency programme, hospital and primary care). Material and methods: cross-sectional, descriptive study of national scope through an online survey of paediatrics residents and hospital-based and primary care paediatricians carried out in March 2022. Results: 326 paediatricians participated, of who 16.8% worked in hospitals, 69.8% in primary care and were 13.4% paediatrics residents. Of this total, 18.8% reported a vocation for preventive care, 60.8% for clinical work and 20.5% for social paediatrics. In addition to carrying a detailed descriptive analysis of the type of reading promotion activities carried out in Spain, we found, firstly, that the vocation for medical practice was associated to the frequency of reading promotion (χ2(2)=13.11; p<0.001), with a higher proportion of paediatricians with a social vocation reporting performance of these activities. Secondly, the care setting also seemed to be a determining factor for the performance of these activities (χ2(2)=19.0; p<0.001), which were conducted more frequently in the primary care setting. Conclusion: activities to promote reading are carried out mainly by primary care professionals within the framework of other health promotion work, and their performance was mainly associated with the greater proportion of primary care professionals with a vocation for social paediatrics. (AU)
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Child Development , Reading , Pediatrics/education , Primary Health Care , Cross-Sectional Studies , Epidemiology, DescriptiveABSTRACT
Outbreaks of bacterial infections in aquaculture have emerged as significant threats to the sustainable production of rainbow trout (Oncorhynchus mykiss) worldwide. Understanding the dynamics of these outbreaks and the bacteria involved is crucial for implementing effective management strategies. This comprehensive review presents an update on outbreaks of bacteria isolated from rainbow trout reported between 2010 and 2022. A systematic literature survey was conducted to identify relevant studies reporting bacterial outbreaks in rainbow trout during the specified time frame. More than 150 published studies in PubMed, Web of Science, Scopus, Google Scholar and relevant databases met the inclusion criteria, encompassing diverse geographical regions and aquaculture systems. The main bacterial pathogens implicated in the outbreaks belong to both gram-negative, namely Chryseobacterium, Citrobacter, Deefgea Flavobacterium, Janthinobacterium, Plesiomonas, Pseudomonas, Shewanella, and gram-positive genera, including Lactococcus and Weissella, and comprise 36 new emerging species that are presented by means of pathogenicity and disturbance worldwide. We highlight the main characteristics of species to shed light on potential challenges in treatment strategies. Moreover, we investigate the role of various risk factors in the outbreaks, such as environmental conditions, fish density, water quality, and stressors that potentially cause outbreaks of these species. Insights into the temporal and spatial patterns of bacterial outbreaks in rainbow trout aquaculture are provided. Furthermore, the implications of these findings for developing sustainable and targeted disease prevention and control measures are discussed. The presented study serves as a comprehensive update on the state of bacterial outbreaks in rainbow trout aquaculture, emphasizing the importance of continued surveillance and research to sustain the health and productivity of this economically valuable species.
ABSTRACT
Objective. The aim was to determine the association between access to dental services and toothbrushing in Peruvian children under 12 years old. Methods. This was a cross-sectional study with a population of 2021 database of the Demographic and Family Health Survey. Records of children under 12 years old who provided answers about their toothbrushing were included. Variables were evaluated descriptively and followed by a bivariate analysis; multivariate tests were performed using Poisson regression with a multilevel regression analysis. Results. General toothbrushing was 96.32% (n = 34 198), and daily toothbrushing was 88.05% (n = 28 444). Access to dental services was associated with general toothbrushing (aPR: 1.18; 95% CI: 1.14-1.22; P < .001), daily toothbrushing (aPR: 1.08; 95% CI: 1.04-1.12; P < .001) and minimum toothbrushing 2 times a day (aPR: 1.12; 95% CI: 1.07-1.17; P < .001). Conclusion. Access to dental services was associated with general toothbrushing, daily toothbrushing and toothbrushing at least twice a day.
ABSTRACT
The prediction of male or semen fertility potential remains a persistent challenge that has yet to be fully resolved. This work analyzed several in vitro parameters and proteome of spermatozoa in bulls cataloged as high- (HF; n = 5) and low-field (LF; n = 5) fertility after more than a thousand artificial inseminations. Sperm motility was evaluated by computer-assisted sperm analysis. Sperm viability, mitochondrial membrane potential (MMP) and reactive oxygen species (mROS) of spermatozoa were assessed by flow cytometry. Proteome was evaluated by the SWATH-MS procedure. Spermatozoa of HF bulls showed significantly higher total motility than the LF group (41.4% vs 29.7%). Rates of healthy sperm (live, high MMP, and low mROS) for HF and LF bull groups were 49% and 43%, respectively (p > 0.05). Spermatozoa of HF bulls showed a higher presence of differentially abundant proteins (DAPs) related to both energy production (COX7C), mainly the OXPHOS pathway, and the development of structures linked with the motility process (TPPP2, SSMEM1, and SPAG16). Furthermore, we observed that equatorin (EQTN), together with other DAPs related to the interaction with the oocyte, was overrepresented in HF bull spermatozoa. The biological processes related to protein processing, catabolism, and protein folding were found to be overrepresented in LF bull sperm in which the HSP90AA1 chaperone was identified as the most DAP. Data are available via ProteomeXchange with identifier PXD042286.
Subject(s)
Proteome , Semen , Male , Cattle , Animals , Proteome/genetics , Proteome/metabolism , Proteomics , Sperm Motility , Spermatozoa/metabolism , Fertility , Sperm-Ovum InteractionsABSTRACT
Camera calibration is necessary for many machine vision applications. The calibration methods are based on linear or non-linear optimization techniques that aim to find the best estimate of the camera parameters. One of the most commonly used methods in computer vision for the calibration of intrinsic camera parameters and lens distortion (interior orientation) is Zhang's method. Additionally, the uncertainty of the camera parameters is normally estimated by assuming that their variability can be explained by the images of the different poses of a checkerboard. However, the degree of reliability for both the best parameter values and their associated uncertainties has not yet been verified. Inaccurate estimates of intrinsic and extrinsic parameters during camera calibration may introduce additional biases in post-processing. This is why we propose a novel Bayesian inference-based approach that has allowed us to evaluate the degree of certainty of Zhang's camera calibration procedure. For this purpose, the a prioriprobability was assumed to be the one estimated by Zhang, and the intrinsic parameters were recalibrated by Bayesian inversion. The uncertainty of the intrinsic parameters was found to differ from the ones estimated with Zhang's method. However, the major source of inaccuracy is caused by the procedure for calculating the extrinsic parameters. The procedure used in the novel Bayesian inference-based approach significantly improves the reliability of the predictions of the image points, as it optimizes the extrinsic parameters.
ABSTRACT
A Gram-staining-negative, oxidase-positive, strictly aerobic rod-shaped bacterium, designated strain PT1T, was isolated from the laboratory-reared larvae of the sea cucumber Apostichopus japonicus. A phylogenetic analysis based on the 16S rRNA gene nucleotide sequences revealed that PT1T was closely related to Neptuniibacter marinus ATR 1.1T (= CECT 8938T = DSM 100783T) and Neptuniibacter caesariensis MED92T (= CECT 7075T = CCUG 52065T) showing 98.2% and 98.1% sequence similarity, respectively. However, the average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) values among these three strains were 72.0%-74.8% and 18.3%-19.5% among related Neptuniibacter species, which were below 95% and 70%, respectively, confirming the novel status of PT1T. The average amino acid identity (AAI) values of PT1T showing 74-77% among those strains indicated PT1T is a new species in the genus Neptuniibacter. Based on the genome-based taxonomic approach, Neptuniibacter victor sp. nov. is proposed for PT1T. The type strain is PT1T (JCM 35563T = LMG 32868T).
Subject(s)
Fatty Acids , Sea Cucumbers , Animals , Phylogeny , Fatty Acids/analysis , Larva/genetics , RNA, Ribosomal, 16S/genetics , Sea Cucumbers/genetics , DNA , Sequence Analysis, DNA , DNA, Bacterial/genetics , DNA, Bacterial/chemistry , Bacterial Typing Techniques , Nucleic Acid HybridizationABSTRACT
The production and loss of fine particles of activated carbon (AC) loaded with gold in the adsorption processes is a worldwide problem, mainly due to the behavior of increasing its adsorption capacity with respect to the decrease in particle size, which becomes relevant to determine the thermodynamic and kinetic activity of the gold adsorption and the economic impact of its loss, with the escape towards the later stages of the system of adsorption, desorption, and reactivation (ADR) plants of AC. Through the adsorption of gold in a synthetic medium with sodium cyanide concentration, using different particle sizes, AC weights, and adsorption times, data were generated for analysis by three different isotherm models, resulting in a better tendency for the Freundlich isotherm, from which thermodynamic parameters of ΔG equal to -2.022 kcal/mol, ΔH equal to -16.710 kcal/mol, and ΔS equal to -0.049 kcal/molK were obtained, which shows that it is a spontaneous, exothermic process with a lower degree of disorder. The kinetic analysis was performed with two different models, from which the pseudo-second-order model was used due to a better tendency and displayed a behavior that leaves open the interpretation of the increase in adsorption with respect to the decrease in the AC particle size but demonstrated the importance of recovering these particles in relation to their gold concentration and the economic impact from their poor recovery, which, for this case study, amounted to ~0.3 million dollars per year.
ABSTRACT
The genus Thalassotalea is ubiquitous in marine environments, and up to 20 species have been described so far. A Gram-staining-negative, aerobic bacterium, designated strain PTE2T was isolated from laboratory-reared larvae of the Japanese sea cucumber Apostichopus japonicus. Phylogenetic analysis based on the 16S rRNA gene nucleotide sequences revealed that PTE2T was closely related to Thalassotalea sediminis N211T (= KCTC 42588T = MCCC 1H00116T) with 97.9% sequence similarity. ANI and in silico DDH values against Thalassotalea species were 68.5-77.0% and 19.7-24.6%, respectively, indicating the novelty of PTE2T. Based on genome-based taxonomic approaches, strain PTE2T (= JCM 34608T = KCTC 82592T) is proposed as a new species, Thalassotalea hakodatensis sp. nov.
Subject(s)
Fatty Acids , Sea Cucumbers , Animals , Phylogeny , RNA, Ribosomal, 16S/genetics , Sea Cucumbers/genetics , Bacterial Typing Techniques , Base Composition , Sequence Analysis, DNA , DNA, Bacterial/genetics , Ubiquinone/genetics , PhospholipidsABSTRACT
The production of customized polymeric hydrogels in the form of 3D scaffolds with application in bone tissue engineering is currently a topic of great interest. Based on gelatin methacryloyl (GelMa) as one of the most popular used biomaterials, GelMa with two different methacryloylation degrees (DM) was obtained, to achieve crosslinked polymer networks by photoinitiated radical polymerization. In this work, we present the obtention of new 3D foamed scaffolds based on ternary copolymers of GelMa with vinylpyrrolidone (VP) and 2-hydroxyethylmethacrylate (HEMA). All biopolymers obtained in this work were characterized by infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA), whose results confirm the presence of all copolymers in the crosslinked biomaterial. In addition, scanning electron microscopy (SEM) pictures were obtained verifying the presence of the porosity created by freeze-drying process. In addition, the variation in its swelling degree and its enzymatic degradation in vitro was analyzed as a function of the different copolymers obtained. This has allowed us to observe good control of the variation in these properties described above in a simple way by varying the composition of the different comonomers used. Finally, with these concepts in mind, biopolymers obtained were tested through assessment of several biological parameters such as cell viability and differentiation with MC3T3-E1 pre-osteoblastic cell line. Results obtained show that these biopolymers maintain good results in terms of cell viability and differentiation, along with tunable properties in terms of hydrophilic character, mechanical properties and enzymatic degradation.
ABSTRACT
Phages depend on their bacterial hosts to replicate. The habitat, density and genetic diversity of host populations are therefore key factors in phage ecology, but our ability to explore their biology depends on the isolation of a diverse and representative collection of phages from different sources. Here, we compared two populations of marine bacterial hosts and their phages collected during a time series sampling program in an oyster farm. The population of Vibrio crassostreae, a species associated specifically to oysters, was genetically structured into clades of near clonal strains, leading to the isolation of closely related phages forming large modules in phage-bacterial infection networks. For Vibrio chagasii, which blooms in the water column, a lower number of closely related hosts and a higher diversity of isolated phages resulted in small modules in the phage-bacterial infection network. Over time, phage load was correlated with V. chagasii abundance, indicating a role of host blooms in driving phage abundance. Genetic experiments further demonstrated that these phage blooms can generate epigenetic and genetic variability that can counteract host defence systems. These results highlight the importance of considering both the environmental dynamics and the genetic structure of the host when interpreting phage-bacteria networks.