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1.
ACS Omega ; 9(31): 33397-33407, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39130539

RESUMO

To delineate a powerful reservoir model, rock type identification is an essential task. Recognizing intervals with promising reservoir quality in a heterogeneous reservoir, such as the Pab Formation, using well logs is critical for better exploration, because coring programs are always impractical due to time and cost constraints. Rock types are described by specific log responses, which are ultimately distinguished with the help of electrofacies. The current study uses a cluster analysis technique for the evaluation of reservoir rock types in the identified sand units. K-means cluster analysis is employed to define electrofacies, which are ultimately classified into four rock types on the basis of reservoir quality, from bad to excellent. Rock typing using cluster analysis has been done for four wells, and a correlation has been made to depict changes in electrofacies. From well-to-well correlation, it can be inferred that the reservoir quality of the Pab Formation at the lower portion of Zamzama-02 and 05 wells is excellent and is defined by rock type 4. The Zamzama-03 well in the southwestern region, on the other hand, has good to moderate reservoir quality, as demonstrated by dominating rock types 3 and 2, respectively. The applied prediction technique to the studied field provides continuous rock type identification for the entire reservoir. Using this methodology in defining rock type is cost-effective, requires less time in the demarcation of zones of interest, and is more accurate than manual analysis of the heterogeneous and thick Pab Formation. The studied approach is not only useful in the exploitation of the heterogeneous Pab Formation but also can be applied to other heterogeneous sandstone reservoirs elsewhere.

2.
Toxins (Basel) ; 16(8)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39195768

RESUMO

HxTx-Hv1h, a neurotoxic peptide derived from spider venom, has been developed for use in commercial biopesticide formulations. Cell Penetrating Peptides (CPPs) are short peptides that facilitate the translocation of various biomolecules across cellular membranes. Here, we evaluated the aphidicidal efficacy of a conjugated peptide, HxTx-Hv1h/CPP-1838, created by fusing HxTx-Hv1h with CPP-1838. Additionally, we aimed to establish a robust recombinant expression system for HxTx-Hv1h/CPP-1838. We successfully achieved the secretory production of HxTx-Hv1h, its fusion with Galanthus nivalis agglutinin (GNA) forming HxTx-Hv1h/GNA and HxTx-Hv1h/CPP-1838 in yeast. Purified HxTx-Hv1h exhibited contact toxicity against Megoura crassicauda, with a 48 h median lethal concentration (LC50) of 860.5 µg/mL. Fusion with GNA or CPP-1838 significantly enhanced its aphidicidal potency, reducing the LC50 to 683.5 µg/mL and 465.2 µg/mL, respectively. The aphidicidal efficacy was further improved with the addition of surfactant, decreasing the LC50 of HxTx-Hv1h/CPP-1838 to 66.7 µg/mL-over four times lower compared to HxTx-Hv1h alone. Furthermore, we engineered HxTx-Hv1h/CPP-1838 multi-copy expression vectors utilizing the BglBrick assembly method and achieved high-level recombinant production in laboratory-scale fermentation. This study is the first to document a CPP fusion strategy that enhances the transdermal aphidicidal activity of a natural toxin like HxTx-Hv1h and opens up the possibility of exploring the recombinant production of HxTx-Hv1h/CPP-1838 for potential applications.


Assuntos
Peptídeos Penetradores de Células , Neurotoxinas , Venenos de Aranha , Venenos de Aranha/química , Venenos de Aranha/genética , Venenos de Aranha/toxicidade , Animais , Peptídeos Penetradores de Células/farmacologia , Peptídeos Penetradores de Células/química , Neurotoxinas/toxicidade , Neurotoxinas/farmacologia , Neurotoxinas/genética , Lectinas de Plantas/farmacologia , Lectinas de Plantas/genética , Lectinas de Plantas/química , Inseticidas/farmacologia , Inseticidas/toxicidade
3.
J Mater Chem B ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39188219

RESUMO

The detrimental effects of widespread pesticide application on the health of living organisms highlight the urgent need for technological advancements in monitoring pesticide residues at trace levels. This study involves the synthesis of a distinctive sensing material, KL@Ni@g-C3N4, which comprises nanocomposites of graphitic carbon nitride with Kraft lignin and nickel. The prepared samples were characterized using FT-IR, PXRD, TEM, SEM, and EDX techniques. The KL@Ni@g-C3N4 nanocomposite was drop-cast on a graphite electrode. Subsequently, this fabricated electrode was used to detect cypermethrin (CYP) residues in drinking water. The redox properties of the fabricated sensors were evaluated using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The limit of detection (LOD) of the fabricated sensor was determined to be 0.026 µg mL-1, which is below the maximum residual limits of CYP in the environment (0.5 µg mL-1) and within the acceptable range for food products (∼0.05 to 0.2 µg mL-1). Therefore, this study proposes a promising alternative to conventional methods for detecting pesticides in drinking water.

4.
J Phys Chem Lett ; 15(33): 8577-8583, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39140785

RESUMO

A progressive aggregation of Tau proteins in the brain is linked to both Alzheimer's disease (AD) and various Tauopathies. This pathological process can be enhanced by several substances, including heparin. However, very little if anything is known about molecules that can inhibit the aggregation of Tau isoforms. In this study, we examined the effect of phosphatidylserines (PSs) with various lengths and saturations of fatty acids (FAs) on the aggregation properties of Tau isoforms with one (1N4R) and two (2N4R) N-terminal inserts that enhance binding of Tau to tubulin. We found that PS with unsaturated and short-length FAs inhibited Tau aggregation and drastically lowered the toxicity of Tau oligomers that were formed in the presence of such phospholipids. Such an effect was not observed for PS with fully saturated long-chain FAs. These results suggest that a short-chain irreversible disbalance between saturated and unsaturated lipids in the brain could be the trigger of Tau aggregation.


Assuntos
Fosfolipídeos , Proteínas tau , Proteínas tau/metabolismo , Proteínas tau/química , Humanos , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Heparina/química , Heparina/farmacologia , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Fosfatidilserinas/química , Fosfatidilserinas/metabolismo , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/química
5.
Front Vet Sci ; 11: 1413237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39193370

RESUMO

African swine fever is a hemorrhagic disease of pigs with high mortality rates. Since its first characterization in 1921, there has been sufficient information about African swine fever virus (ASFV) and related diseases. The virus has been found and maintained in the sylvatic cycle involving ticks and domestic and wild boars in affected regions. The ASFV is spread through direct and indirect contact with infected pigs, their products and carrier vectors especially Ornithodoros ticks. Severe economic losses and a decline in pig production have been observed in ASFV affected countries, particularly in sub-Saharan Africa and Europe. At the end of 2018, the ASFV adversely affected China, the world's leading pork-producer. Control strategies for the disease remained challenging due to the unavailability of effective vaccines and the lack of successful therapeutic measures. However, considerable efforts have been made in recent years to understand the biology of the virus, surveillance and effective control measures. This review emphasizes and summarizes the current state of information regarding the knowledge of etiology, epidemiology, transmission, and vaccine-based control measures against ASFV.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39052462

RESUMO

This paper presents a high accuracy air-coupled acoustic rangefinder based on piezoelectric microcantilever beam array using continuous waves. Cantilevers are used to create a functional ultrasonic rangefinder with a range of 0 m up to 1 m. This is achieved through a design of custom arrays. This research investigates various classification techniques to identify airborne ranges using ultrasonic signals. The initial approach involves implementing individual models like the Support Vector Machine (SVM), Gaussian Naive Bayes (GNB), Logistic Regression (LR), k-Nearest Neighbors (kNN), and Decision Tree (DT). To potentially achieve better performance, the study introduces a Deep Learning (DL) architecture based on Convolutional Neural Networks (CNN) to categorize different ranges. The CNN model combines the strengths of multiple classification models, aiming for more accurate range detection. To ensure the model generalizes well to unseen data, a technique called k-fold cross-validation, which provides the reliability assessment, is employed. The proposed framework demonstrates a significant improvement in accuracy (100%), and AUC (1.0) over other approaches.

7.
Acta Trop ; 257: 107317, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38981566

RESUMO

BACKGROUND: Tuberculosis (TB) as a foremost infectious disease adds massive burden to morbidity and mortality rate, despite of well-structured TB control programs around the globe. Inappropriate health care management system and poor implementation on standard in relevance to TB, remain some reasons causative to TB prevalence and its rising antimicrobial resistance. Health Care Workers (HCWs) laboring as a part of TB control system, are the vital warriors in achieving the goals of TB End Strategy by 2035. Their performance is influenced by their knowledge, attitude, and practices (KAP) toward this infectious disease. This study aimed to signify the role of KAP score of health care Workers in the better control and prevention of TB in the Islamabad Capital Territory (ICT), Pakistan. METHODS: A cross-sectional study on Knowledge, Attitude and Practice study of Tuberculosis (TB) among health care Workers, was done in ICT, which is the capital of Pakistan. The KAP of TB was collected for the 306 Health Care Workers from all the Islamabad TB referring health facilities which refer the TB patients for testing to the National Reference Laboratory, Islamabad Pakistan. Eligible health care workers were requested to respond on KAP questionnaire after informed consent. KAP questionnaire comprised of knowledge, attitude, and practices section including demographic information. All the data was analyzed using IBM SPSS statistics 21. One Way Analysis of Variance (ANOVA) was applied to calculate KAP mean score against different variables. On the significant data sets of ANOVA output, Tukey's Multiple Comparison Test was applied for pairwise comparison. Pearson correlation coefficient was utilized to explore the association between two qualitative variables. The non-parametric tests were applied to evaluate difference of KAP score in relation to demographic covariates individually. RESULTS: From June to July 2023, we conducted TB KAP study among Health Care Workers of ICT, Pakistan. The average age was 33 years (range 26-30 years). Majority of the recruited subjects were not being trained for dealing with TB infection. The results demonstrated that Health Care Workers working were lacking their knowledge about mode of TB transmission, best diagnostic technique, and contraction of TB infections. The mean knowledge, attitude and practices mean scores were 15.05 (SD = 3.96), 83.68 (SD = 15.74) and 6.31 (SD = 2.21), respectively. Mean knowledge score of Health Care Workers were significantly related to their educational level and occupation while no significant association was declared with working experience as TB staff. Pearson coefficient of attitude score with knowledge of Health Care Workers was of weak level (0.28). Practice mean score was correlated to knowledge mean score at a moderate level (r = 0.40). On the other hand, practice score was r = 0.29 with attitude mean score had shown weak level correlation. A number of demographic factors were strongly linked to each of the mean score of knowledge, attitude, and practices. CONCLUSION: These findings highlighted the significant involvement of education, profession, and professional trainings in the better knowledge, attitude, and practices of the TB related health care Workers. For a better management system of infectious diseases like TB, a well-trained and professionally competent staff of Health Care Workers is important so as to achieve the goal of TB-End strategy by 2035 from Pakistan, which is the 5th highest burden country for TB.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Tuberculose , Humanos , Paquistão/epidemiologia , Estudos Transversais , Pessoal de Saúde/psicologia , Pessoal de Saúde/estatística & dados numéricos , Masculino , Adulto , Feminino , Tuberculose/prevenção & controle , Tuberculose/epidemiologia , Inquéritos e Questionários , Pessoa de Meia-Idade , Atitude do Pessoal de Saúde , Adulto Jovem
8.
ACS Omega ; 9(29): 31237-31253, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39072056

RESUMO

Soil salinization is a serious concern across the globe that is negatively affecting crop productivity. Recently, biochar received attention for mitigating the adverse impacts of salinity. Salinity stress induces osmotic, ionic, and oxidative damages that disturb physiological and biochemical functioning and nutrient and water uptake, leading to a reduction in plant growth and development. Biochar maintains the plant function by increasing nutrient and water uptake and reducing electrolyte leakage and lipid peroxidation. Biochar also protects the photosynthetic apparatus and improves antioxidant activity, gene expression, and synthesis of protein osmolytes and hormones that counter the toxic effect of salinity. Additionally, biochar also improves soil organic matter, microbial and enzymatic activities, and nutrient and water uptake and reduces the accumulation of toxic ions (Na+ and Cl), mitigating the toxic effects of salinity on plants. Thus, it is interesting to understand the role of biochar against salinity, and in the present Review we have discussed the various mechanisms through which biochar can mitigate the adverse impacts of salinity. We have also identified the various research gaps that must be addressed in future study programs. Thus, we believe that this work will provide new suggestions on the use of biochar to mitigate salinity stress.

9.
Ticks Tick Borne Dis ; 15(6): 102361, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38880004

RESUMO

The genus Amblyomma contains the highest percentage of reptile-associated ticks, and comprises approximately nine subgenera. One of these subgenera is Adenopleura, which also encompasses Amblyomma javanense, and its type species Amblyomma compressum. This study describes a new Amblyomma species associated with Bengal monitor lizards (Varanus bengalensis) based on morphology and its mitogenome in Khyber Pakhtunkhwa, Pakistan. Reptiles belonging to different genera were examined for Amblyomma ticks and only the monitor lizard was infested with ticks in the District Bajaur. Collected Amblyomma cf. javanense ticks were analyzed and formally described as a new species. Overall, 57 A. cf. javanense ticks were collected on monitor lizards (4/27) with a 15% prevalence of infestation, 2.1 mean abundance, and 14.3 mean intensity. Ticks comprised males (n = 23, 40%), females (n = 14, 25%) and nymphs (n = 20, 35%), while no larvae were found. BLAST analysis of A. cf. javanense sequences showed the following maximum identities; 98.25% with undetermined Amblyomma species based on 12S rRNA, 96.07% with A. javanense based on 16S rRNA, 99.56% and 90.95% with an Amblyomma sp. and A. javanense, respectively, based on ITS2. Moreover, the mitochondrial genome of A. cf. javanense showed maximum identities of 80.75%, 80.48% and 79.42% with Amblyomma testudinarium, A. javanense, and Amblyomma sp., respectively. The phylogenetic analysis of A. cf. javanense revealed that its 12S rRNA and 16S rRNA are closely related to an Amblyomma sp. and A. javanense, respectively, from Sri Lanka, its ITS2 is closely related to A. javanense from China and an Amblyomma sp. from Sri Lanka, and its mitogenome is closely related to A. javanense and Amblyomma sp. from China. The pairwise distance analysis resulted in divergence of 0-1.71% (12S rRNA), 0-17.5% (16S rRNA), 0-9.1% (ITS2) and 0-20.5% (mitochondrial genome). We also contributed the full-length mitochondrial genome sequence of A. compressum and showed that this species does not share a most recent common ancestor with A. javanense. As the subgenus Adenopleura is paraphyletic, this study could help to understand the systematics and phylogeny of this taxon.

10.
Front Nutr ; 11: 1371672, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38899322

RESUMO

Pollen grains are the male reproductive part of the flowering plants. It is collected by forager honey bees and mixed with their salivary secretions, enzymes, and nectar, which form fermented pollen or "bee bread" which is stored in cells of wax honeycombs. Bee pollen (BP) is a valuable apitherapeutic product and is considered a nutritional healthy food appreciated by natural medicine from ancient times. Recently, BP has been considered a beneficial food supplement and a value-added product that contains approximately 250 different bioactive components. It contains numerous beneficial elements such as Mg, Ca, Mn, K, and phenolic compounds. BP possesses strong antioxidant, anti-inflammatory, antimicrobial, antiviral, analgesic, immunostimulant, neuroprotective, anti-cancer, and hepatoprotective properties. It is used for different purposes for the welfare of mankind. Additionally, there is a growing interest in honey bee products harvesting and utilizing for many purposes as a natural remedy and nutritive function. In this review, the impacts of BP on different organisms in different ways by highlighting its apitherapeutic efficacy are described.

11.
Neurobiol Dis ; 198: 106553, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38839022

RESUMO

α-Synuclein (α-syn) is a small protein that is involved in cell vesicle trafficking in neuronal synapses. A progressive aggregation of this protein is the expected molecular cause of Parkinson's disease, a disease that affects millions of people around the world. A growing body of evidence indicates that phospholipids can strongly accelerate α-syn aggregation and alter the toxicity of α-syn oligomers and fibrils formed in the presence of lipid vesicles. This effect is attributed to the presence of high copies of lysines in the N-terminus of the protein. In this study, we performed site-directed mutagenesis and replaced one out of two lysines at each of the five sites located in the α-syn N-terminus. Using several biophysical and cellular approaches, we investigated the extent to which six negatively charged fatty acids (FAs) could alter the aggregation properties of K10A, K23A, K32A, K43A, and K58A α-syn. We found that FAs uniquely modified the aggregation properties of K43A, K58A, and WT α-syn, as well as changed morphology of amyloid fibrils formed by these mutants. At the same time, FAs failed to cause substantial changes in the aggregation rates of K10A, K23A, and K32A α-syn, as well as alter the morphology and toxicity of the corresponding amyloid fibrils. Based on these results, we can conclude that K10, K23, and K32 amino acid residues play a critical role in protein-lipid interactions since their replacement on non-polar alanines strongly suppressed α-syn-lipid interactions.


Assuntos
Mutagênese Sítio-Dirigida , alfa-Sinucleína , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , Humanos , Amiloide/metabolismo , Amiloide/genética , Ácidos Graxos/metabolismo
12.
Protein Sci ; 33(7): e5078, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38895991

RESUMO

Alzheimer's disease is the fastest-growing neurodegenerative disease that affects over six million Americans. The abnormal aggregation of amyloid ß peptide and Tau protein is the expected molecular cause of the loss of neurons in brains of AD patients. A growing body of evidence indicates that lipids can alter the aggregation rate of amyloid ß peptide and modify the toxicity of amyloid ß aggregates. However, the role of lipids in Tau aggregation remains unclear. In this study, we utilized a set of biophysical methods to determine the extent to which phospatidylserine (PS) altered the aggregation properties of Tau isoforms with one (1N4R) and two (2N4R) N terminal inserts that enhance the binding of Tau to tubulin. We found that the length and saturation of fatty acids (FAs) in PS altered the aggregation rate of 2N4R isoform, while no changes in the aggregation rate of 1N4R were observed. These results indicate that N terminal inserts play an important role in protein-lipid interactions. We also found that PS could change the toxicity of 1N4R and 2N4R Tau fibrils, as well as alter molecular mechanisms by which these aggregates exert cytotoxicity to neurons. Finally, we found that although Tau fibrils formed in the presence and absence of PS endocytosed by cells, only fibril species that were formed in the presence of PS exert strong impairment of the cell mitochondria.


Assuntos
Fosfatidilserinas , Tubulina (Proteína) , Proteínas tau , Proteínas tau/metabolismo , Proteínas tau/química , Proteínas tau/toxicidade , Humanos , Fosfatidilserinas/metabolismo , Fosfatidilserinas/química , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/química , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Ligação Proteica , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Agregados Proteicos , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/química
13.
Environ Int ; 190: 108834, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38908278

RESUMO

High-risk antibiotic resistance genes (ARGs) in reclaimed water-irrigated soil pose a potential threat to ecosystem and human health. Inorganic fertilization - including with nitrogen, a key ingredient in agricultural production - may affect the ARG profile in soil. However, little is known about nitrogen fertilization's influence on ARGs profiles in the soil-plant system. This study investigated the effects of different nitrogen fertilizer types (CO(NH2)2, NO3--N (NaNO3) and NH4+-N (NH4HCO3)) and different nitrogen fertilizer application rates (low, medium, high) on the distribution of high-risk ARGs in reclaimed water-irrigated soil and plants using quantitative PCR, high-throughput sequencing and metagenomic sequencing. Soil microcosms results revealed that nitrogen fertilization significantly affected the pattern of high-risk ARGs in soil, and also affected high-risk ARGs abundance and transfer capacity in plants. Compared with nitrogen fertilizer application rate, nitrogen fertilizer types significantly contributed to enhancing the soil resistome, with the order of CO(NH2)2 > NO3--N ≈ NH4+-N. The medium application of NO3--N and NH4+-N significantly reduced high-risk ARGs abundance in the leaf endophyte. Bacterial community mainly drove the variation of ARGs in nitrogen-fertilized soil-plant system, and class I integron and metal resistance genes (MRGs) also had direct effects on these high-risk ARGs. A similar high-risk ARGs pattern was also found in field plot experiments, and several dangerous pathogens were observed as the main high-risk ARGs potential hosts in nitrogen-fertilized soil. Based on an economic assessment, application of NH4+-N (NH4HCO3) could reduce costs by $1,312.83 ha-1 compared with NO3--N (NaNO3). These results showed that the more important role of nitrogen type might be an effective and economical way to control high-risk ARGs spread in soil-plant system under reclaimed water irrigation.


Assuntos
Resistência Microbiana a Medicamentos , Fertilizantes , Nitrogênio , Microbiologia do Solo , Solo , Resistência Microbiana a Medicamentos/genética , Solo/química , Irrigação Agrícola/métodos , Plantas
14.
Vet Parasitol ; 330: 110224, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38861910

RESUMO

The identification and characterization of tick proteins allow us to discover new physiological targets useful for the development of tick control methods. Bm05br (Brazil Rhipicephalus microplus protein 05) is a protein with unknown function identified in the saliva of R. microplus. Rs05br (Brazil Rhipicephalus sanguineus protein 05), a protein with 99 % similarity to Bm05br, was identified in Rhipicephalus linnaei egg, larval, and nymphal stages, as well as in adult saliva. To improve the knowledge about both proteins, immunological characterization was performed, including antigenicity analysis, vaccination trials, and artificial feeding. The sequence and antigenicity analysis of Bm05br and Rs05br proteins showed that R. linnaei could serve as a tick model for cross-protection studies. The recombinant Bm05br protein was immunogenic. Anti-Bm05br antibodies recognized the homologous protein Rs05br in different stages, organs, and in the saliva of R. linnaei. Although rBm05br did not induce a protective response against infestation in R. linnaei in this study, further experiments could be developed taking into account new formulations and animal models for vaccination. These results also serve as a reference for future research on the function of these proteins in R. microplus and R. linnaei physiology, as well as other species of the genus Rhipicephalus.


Assuntos
Proteínas de Artrópodes , Rhipicephalus , Infestações por Carrapato , Animais , Rhipicephalus/imunologia , Rhipicephalus/química , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/química , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Infestações por Carrapato/imunologia , Infestações por Carrapato/prevenção & controle , Feminino , Proteínas Recombinantes/imunologia , Coelhos , Larva/imunologia , Saliva/imunologia , Saliva/química , Sequência de Aminoácidos
15.
Phys Rev Lett ; 132(17): 173402, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728730

RESUMO

We propose a method to change the effective interaction between two fluids by modulation of their local density distributions with external periodic potentials, whereby the mixing properties can be controlled. This method is applied to a mixture of dilute bosonic gases, and binodal and spinodal curves emerge in the phase diagram. Spinodal decomposition into a mixed-bubble state becomes possible, in which one of the coexisting phases has a finite mixing ratio. A metastable mixture is also realized, which undergoes phase separation via nucleation.

16.
ACS Appl Bio Mater ; 7(5): 3283-3294, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727030

RESUMO

Medical implants are constantly facing the risk of bacterial infections, especially infections caused by multidrug resistant bacteria. To mitigate this problem, gold nanoparticles with alkyl bromide moieties (Au NPs-Br) on the surfaces were prepared. Xenon light irradiation triggered the plasmon effect of Au NPs-Br to induce free radical graft polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA), leading to the formation of poly(DMAEMA) brush-grafted Au NPs (Au NPs-g-PDM). The Au NPs-g-PDM nanocomposites were conjugated with phytic acid (PA) via electrostatic interaction and van der Waals interaction. The as-formed aggregates were deposited on the titanium (Ti) substrates to form the PA/Au NPs-g-PDM (PAP) hybrid coatings through surface adherence of PA and the gravitational effect. Synergistic bactericidal effects of contact-killing caused by the cationic PDM brushes, and local heating generated by the Au NPs under near-infrared irradiation, conferred strong antibacterial effects on the PAP-deposited Ti (Ti-PAP) substrates. The synergistic bactericidal effects reduced the threshold temperature required for the photothermal sterilization, which in turn minimized the secondary damage to the implant site. The Ti-PAP substrates exhibited 97.34% and 99.97% antibacterial and antiadhesive efficacy, respectively, against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared to the control under in vitro antimicrobial assays. Furthermore, the as-constructed Ti-PAP surface exhibited a 99.42% reduction in the inoculated S. aureus under in vivo assays. In addition, the PAP coatings exhibited good biocompatibility in the hemolysis and cytotoxicity assays as well as in the subcutaneous implantation of rats.


Assuntos
Antibacterianos , Escherichia coli , Ouro , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Ácido Fítico , Staphylococcus aureus , Ouro/química , Ouro/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanopartículas Metálicas/química , Ácido Fítico/química , Ácido Fítico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Animais , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Cátions/química , Cátions/farmacologia , Polímeros/química , Polímeros/farmacologia , Titânio/química , Titânio/farmacologia
17.
Colloids Surf B Biointerfaces ; 240: 113976, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38795585

RESUMO

In this study, UV-vis spectroscopy was employed to investigate the interaction between formylphenoxyacetic acid (FPAA) and its derivatives (chalcone and flavones) with ionic surfactants (SDS, CTAB, and DTAB) in different physiological environments. Changes in the physiochemical properties of FPAA chalcone and flavones including binding constants, partitioning constants, and Gibbs free energy were observed which were influenced by the presence of ionic surfactants computed using mathematical models. The solubilization of the targeted compounds in the ionic surfactants was determined through the binding constant (Kb). The results of the present study indicated that electrostatic interactions played a significant role in the solubilization of the targeted compounds in SDS, CTAB, and DTAB. At pH 4.1, FPAA chalcone exhibited stronger binding affinity with SDS compared to CTAB and DTAB. However, at pH 7.4, chalcone showed stronger binding with DTAB compared to SDS, while negligible interaction with CTAB was observed at pH 7.4. The flavones demonstrated stronger binding with DTAB at pH 7.4 compared to SDS and CTAB and it exhibited strong bonding with CTAB at pH 4.1. The negative values of the Gibbs free energy for binding (ΔGb˚) and partitioning (ΔGp˚) constants displayed the spontaneity of the process. However, FPAA chalcone with SDS and FPAA flavones with DTAB furnished positive ΔGb˚, indicating a non-spontaneous process.


Assuntos
Flavonas , Solubilidade , Tensoativos , Tensoativos/química , Flavonas/química , Flavonas/metabolismo , Concentração de Íons de Hidrogênio , Cetrimônio/química , Termodinâmica , Íons/química , Chalcona/química , Chalconas/química , Chalconas/metabolismo , Dodecilsulfato de Sódio/química , Eletricidade Estática
18.
Bioengineering (Basel) ; 11(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38790371

RESUMO

Bartonella henselae is a Gram-negative bacterium causing a variety of clinical symptoms, ranging from cat-scratch disease to severe systemic infections, and it is primarily transmitted by infected fleas. Its status as an emerging zoonotic pathogen and its capacity to persist within host erythrocytes and endothelial cells emphasize its clinical significance. Despite progress in understanding its pathogenesis, limited knowledge exists about the virulence factors and regulatory mechanisms specific to the B. henselae strain Houston-1. Exploring these aspects is crucial for targeted therapeutic strategies against this versatile pathogen. Using reverse-vaccinology-based subtractive proteomics, this research aimed to identify the most antigenic proteins for formulating a multi-epitope vaccine against the B. henselae strain Houston-1. One crucial virulent and antigenic protein, the PAS domain-containing sensor histidine kinase protein, was identified. Subsequently, the identification of B-cell and T-cell epitopes for the specified protein was carried out and the evaluated epitopes were checked for their antigenicity, allergenicity, solubility, MHC binding capability, and toxicity. The filtered epitopes were merged using linkers and an adjuvant to create a multi-epitope vaccine construct. The structure was then refined, with 92.3% of amino acids falling within the allowed regions. Docking of the human receptor (TLR4) with the vaccine construct was performed and demonstrated a binding energy of -1047.2 Kcal/mol with more interactions. Molecular dynamic simulations confirmed the stability of this docked complex, emphasizing the conformation and interactions between the molecules. Further experimental validation is necessary to evaluate its effectiveness against B. henselae.

19.
J Phys Chem Lett ; 15(17): 4761-4766, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38661515

RESUMO

Heart tissue can experience a progressive accumulation of transthyretin (TTR), a small four subunit protein that transports holoretinol binding protein and thyroxine. This severe pathology is known as transthyretin amyloid cardiomyopathy. Numerous experimental studies indicated that the aggregation rate and toxicity of TTR fibrils could be altered by the presence of lipids; however, the role of plasmalogens in this process remains unknown. In this study, we investigate the effect of choline plasmalogens (CPs) with different lengths and saturations of fatty acids (FAs) on TTR aggregation. We found that CPs with saturated and unsaturated FAs strongly suppressed TTR aggregation. We also found that CPs with saturated FAs did not change the morphology of TTR fibrils; however, much thicker fibrillar species were formed in the presence of CPs with unsaturated FAs. Finally, we found that CPs with C16:0, C18:0, and C18:1 FAs substantially lowered the cytotoxicity of TTR fibrils that were formed in their presence.


Assuntos
Plasmalogênios , Pré-Albumina , Pré-Albumina/química , Pré-Albumina/metabolismo , Plasmalogênios/metabolismo , Plasmalogênios/química , Humanos , Amiloide/química , Amiloide/metabolismo , Agregados Proteicos/efeitos dos fármacos , Ácidos Graxos/química , Ácidos Graxos/metabolismo
20.
Parasitology ; : 1-10, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38586995

RESUMO

Two major families exist in ticks, the Argasidae and Ixodidae. The Argasidae comprise 2 sub-families, Argasinae and Ornithodorinae. The placement into subfamilies illuminate differences in morphological and molecular systematics and is important since it provides insight into evolutionary divergence within this family. It also identifies fundamental gaps in our understanding of argasid evolution that provide directions for future research. Molecular systematics based on mitochondrial genomics and 18S/28S ribosomal RNA confirmed the placement of various genera and subgenera into the Argasinae: Argas (including Argas and Persicargas), Navis, Ogadenus, Otobius lagophilus, Proknekalia, Secretargas and the Ornithodorinae: Alectorobius, Antricola (including Antricola and Parantricola), Carios, Chiropterargas, Nothoaspis, Ornithodoros (including Microargas, Ornamentum, Ornithodoros sensu strictu, Pavlovskyella), Otobius sensu strictu, Reticulinasus and Subparmatus. The position of Alveonasus remains controversial since traditional taxonomy placed it in the Ornithodorinae, while cladistic and limited molecular analysis placed it in the Argasinae. The current study aimed to resolve the systematic position of Alveonasus using mitochondrial genomic and 18S/28S ribosomal RNA systematics by sequencing the type species Alveonasus lahorensis from Pakistan. In addition, the mitochondrial genomes for Argas reflexus and Alectorobius kelleyi are reported from Germany and the USA, respectively. The systematic data unambiguously place Alveonasus in the Argasinae and also suggest that Alveonasus may be another paraphyletic genus.

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