Impact of Chromium Oxide Nanoparticles on Growth and Biofilm Formation of Persistence Klebsiella pneumoniae Isolates

Bacterial persistence is recognized as a major cause of antibiotic therapy failure, causing biofilms and chronic intractable infections. The emergence of persisters in K. pneumoniae isolates has become a worldwide public health concern. Despite this clinical threat, currently, there are no viable means for eradicating K. pneumoniae persisters. In this project, chromium oxide (Cr2O3) nanoparticles were synthesized by the photochemical method. The morphology, topographic and physical properties of nano-synthesized were described by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray powder diffraction (XRD), and ultraviolet-visible spectroscopy (UV. vis) measurements. The obtained average size of Cr2O3-NPs was to be ranging from 11 to 30 nm. The activities of the Cr2O3-NPs for antibacterial and antibiofilm formation against persistent K. pneumoniae were assessed. The result showed a significant inhibitory effect of Cr2O3-NPs against K. pneumoniae. A, where the zones of inhibition were 12-18 mm, and the minimum inhibitory concentration (MIC) was 625 μg/mL. The concentration of Cr2O3-NPs of 10 mg/mL demonstrated the highest inhibition activity against biofilm formation (73.95 ± 2.17%), indicating the lowest inhibition (19.08 ± 1.32%) at a level of 0.625 mg/mL. Cr2O3-NPs therefore had a positive impact on biofilms that were produced by persistence isolates of K. pneumoniae

Synthesis, Characterization, Spectroscopic and Biological Studies of Zn(Ⅱ), Mn(Ⅱ) and Fe(Ⅱ) Theophylline Complexes in Nanoscale

Three nanocomplexes of Zn(Ⅱ), Mn(Ⅱ), Fe(Ⅱ) with theophylline were synthesized by ultrasonic sonication method. Melting point, molar conductivity, solubility, flame atomic absorption, Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis) spectroscopy and C/H/N elemental analyses were used to investigate and suggest the structure of the nanocomplexes. Size and morphology of the nanocomplexes were measurement by transmission electron microscopy (TEM), ranging from 6-22 nm. Efficacy of the nanocomplexes synthesized was examined against four types of bacterial strains: Staphylococcus aureus, Bacillus subtilis (Gram-positive bacteria), Klebsiella pneumonia and Escherichia coli (Gram-negative bacteria). The results showed that all nanocomplexes had very high susceptibility to inhibit bacterial growth, as indicated by their inhibition zones between 98% and 100%

Nanoscale Synthesis of Metal(II) Theophylline Complexes and Assessment of Their Biological Activity

Three nanocomplexes of Cu(Ⅱ), Co(Ⅱ), and Ni(Ⅱ) with theophylline were synthesized by ultrasonic sonication method. This method was used to produce smaller and narrow-distributed nanoparticles without any aggregations. Melting point, molar conductivity, solubility, flame atomic absorption, Fourier-transform infrared spectroscopy (FTIR) and elemental analysis (C, H, N, and S) were used to identify and to suggest the structure of the synthesized nanocomplexes. The transmission electron microscopy (TEM) results exhibited that the size of nanocomplexes was in the range of 15-25 nm. The efficacy of the synthesized nanocomplexes was examined against four types of bacterial strains, Staphylococcus aureus, Bacillus subtilis (gram-positive bacteria), and Klebsiella pneumoniae, Escherichia Coli (gram-negative bacteria). The results showed that all nanocomplexes had very high susceptibility to inhibit bacterial growth, as they resulted in an inhibition zone between 98% and 100%. The copper nanocomplex gave the highest inhibition zone by 100% for each type of bacterial strains, due to the surface plasmon. Therefore, a further test for the copper nanocomplex Cu(THP)2(H2O)2(Cl)2 was carried out on skin injuries of laboratory mice after it was converted into cream with vaseline and was found to have a very potent influence in healing skin injuries

Inhibition Effect ofCopper (Ⅱ) Theophylline Nanocomplex on Phosphodiesterase (PDE) Enzyme Activity in Human Serum of Iraqi Patients with Asthma Disease

Copper (Ⅱ) theophylline [Cu(THP)2(H2O)4] complex in nanoscale has synthesized by ultrasonic sonication method. This method was used in the development of smaller, dispersed, and unaggregated nanoparticles (NPs). The structure of nanocomplex was described and suggested by the molar conductance, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), solubility, atomic fire absorption, and C.H.N. elemental analysis as octahedral geometry. The size and morphology of nanocomplex measured by transmission electron microscopy (TEM) were 20 nm. The nanocomplex was studied on phosphodiesterase enzyme activity in human serum of Iraqi patient?s asthma disease. The results showed a highly significant (p < 0.01) increase in the serum levels of phosphodiesterase enzyme activity in asthma patients (mean = 14.939 ± 3.021 ng/mL) compared with a control group (mean = 9.974 ± 2.032 ng/mL). The result also showed a highly significant (p < 0.01) decrease in the serum levels of phosphodiesterase activity in patients of asthma disease with theophylline (mean = 11.253 ± 2.479 ng/mL) compared to serum patients without nano and control groups. It is vital that the result showed a highly significant (p < 0.01) decrease in the serum levels of phosphodiesterase activity in patients of asthma disease with copper nano complex (mean = 9.563 ± 2.082 ng/mL) compared in patients of asthma disease with and without theophylline. As for comparing asthma disease with copper nano complex and control group, the result showed there was no significant effect (p > 0.05)

An overview of nanoparticles in drug delivery: Properties and applications

Today, in diverse medical and clinical fields, including cancer treatment, nanoscience has evolved and evolved. Cancer and its forms, on the other hand, have been rumored and inclusive, and many individuals suffer from this fatal and lethal condition. Actually, even with the medicinal effect, current therapeutic approaches, including chemotherapy, radiotherapy, etc., create symptoms that are inconvenient for patients. Scientists and scholars are also working to establish and, strengthen the options and methods of therapy to deal with this dangerous illness. Nanoscience and nanotechnology have been popular today, their different areas, including nanoparticles, are commonly used for a number of applications, especially for drug delivery and diagnostic products, and cases of imaging. Release mechanisms focused on nanotechnology have a profound effect on the release of cancer drugs. Biomaterials and bio-engineering developments are leading to novel approaches to nanoparticles that could offer a new way for cancer patients to improve. In the drug release method, Nano-technology has had a great effect on the selection of cancer cells, the release of a targeted drug, and the overcoming of traditional chemotherapy limitations. This article discusses the drug delivery to tumor tissue, a method that is more effective than traditional drug delivery methods, also many new nanoparticles have solved the problem of cell resistance to the drug, provided a new field in the treatment of cancer

Nanomaterials as transmitters of non-viral gene vectors: A review

With the rapid development of nanotechnology in the recent decade, novel DNA and RNA delivery systems for gene therapy have become available that can be used instead of viral vectors. These non-viral vectors can be made of a variety of materials, including inorganic nanoparticles, carbon nanotubes, liposomes, protein and peptide-based nanoparticles, as well as nanoscale polymeric materials. They have as advantages over viral vectors a decreased immune response, and additionally offer flexibility in design, allowing them to be functionalized and targeted to specific sites in a biological system with low cytotoxicity.gene therapy keeps hopes a life for the treatment of a wide range of diseases such as cancer, nano particles are now known as promising carriers for the effective and safe vectors of genes to specific cells or tissues. This could provide alternative therapies for conventional approaches that use viruses as gene carriers. The expression of genetic material such as DNA, RNA into cells and tissues has raised considerable hopes for therapeutic and diagnostic purposes. But getting nucleic acids into the cell also faces challenges. These challenges are less for non-virus carriers as a gene and drug vectors method than for viral or free vectors and are therefore considered less risky and more appropriate. of expanding nonverbal nano carriers, we will look at a few of these nano carriers, penicillin, PEI, PLGA, silica, block copolymer, Quantum dot, gold nano particles, and common carbon nano tubes. Problems include the use of nano particles such as polymer nano particles, liposomes, solid lipid particles, in targeted gene vectors will be investigated. Gene-based therapy is the intentional modulation of gene expression in specific cells to treat pathological conditions. This modulation is accomplished by introducing exogenous nucleic acids such as DNA, mRNA, small interfering RNA (siRNA), microRNA (miRNA) or antisense oligonucleotides. Given the large size and the negative charge of these macromolecules, their delivery is typically mediated by carriers or vectors. In this Review, we introduce the biological barriers to gene delivery in vivo and discuss recent advances in material sciences, nanotechnology and nucleic acid chemistry that have yielded promising non-viral delivery systems, some of which are currently undergoing testing in clinical trials. The diversity of these systems highlights the recent progress of gene-based therapy using non-viral approaches

Investigation of effective parameters in the production of alumina gel through the sol-gel method

Sol-gel chemistry is currently applied as one of the most widely used methods for synthesis of nanoparticles. In this method hydrolysis and poly-condensation reactions occur when the gel precursors are mixed with water and catalyst. The further condensation of sol particles into a three-dimensional network produces a gel. There are several parameters that effect on gelation time such as the molar ratio of alkoxide to water, the rate of hydrolysis, the type and amount of catalyst used, initial concentration of precursors and the temperature of hydrolysis and drying. Encapsulated solvent can be removed from a gel by either evaporative drying or supercritical drying. Where the resulting solids are known as a xerogel and an aerogel, respectively. During the drying process due to the surface tension of the liquid, a capillary pressure gradient is built in the pore walls, which is able to collapse most part of the pore volume. The volume shrinkage may be prevented by supercritical drying. The strength, thermal stability, pore structure and morphology of aerogels are keys to success for wider applications such as catalyst supports, thermal and acoustic insulators and adsorbents. Among catalyst support materials, alumina became popular recently due to its highly thermal and chemical stability and higher porosity. In the present study, synthesis of alumina gel as a support for nano-catalysts through hydrolysis of aluminum tri-sec-butoxide (ASB) in ethanol was investigated. The gel synthesis was carried out at 32 and 60 °C with different concentrations of water and precursor and different types and amounts of acid as catalyst. Rate of gel formation, efficiency of hydrolysis and polymerization and amount of gel production were measured and discussed. Results showed that acid addition around 0.2 ml and water to ASB malar ratio of 2 at 60 °C maximized the amount of gel produced and minimized the gelation time. Then, the alumina gel that synthesized at optimum conditions was dried by two different methods, at atmospheric pressure and temperature and at supercritical conditions of carbon dioxide and the results of Scanning Electron Microscopy were compared

Investigation of mechanical properties and transparency of spark plasma sintered Mg2+ and Y3+ codoped α-Al2O3 nanoparticles synthesized via coprecipitation

This research aims to investigate the effect of different amounts of doping elements (magnesium and yttrium ions) on the hardness, elastic modulus, flexural strength, and transparency of alumina ceramics. For this purpose, different amounts of Mg2+ and Y3+ doped α-Al2O3 nanoparticles were synthesized via the co-precipitation method. The results revealed that the majority of Mg2+ and Y3+ doped α-Al2O3 nanoparticles have a particle size of 300–400 nm. Furthermore, the density and transparency (60% in-line transmittance at a wavelength of 5 μm, with a sample thickness of 2.4 mm) of the bulk materials prepared with doping of 100 ppm Mg2+and 400 ppm Y3+ (100M400Y) presented the best performance compared with other samples. Furthermore, the hardness and Young modulus of this sample were 28 GPa and 349 GPa, respectively. The flexural strength of the 100M400Y sample reached the highest value, 193 MPa, due to the smaller grain size and minimal porosity

Efficacy and Safety of Tixagevimab/Cilgavimab to Prevent COVID-19 (Pre-Exposure Prophylaxis): A Systematic Review and Meta-Analysis

Background: Tixagevimab/cilgavimab (TGM/CGM) are neutralizing monoclonal antibodies (mAbs) directed against different epitopes of the receptor-binding domain of the SARS-CoV-2 spike protein that have been considered as pre-exposure prophylaxis (PrEP). Objectives: This study seeks to assess the efficacy and safety of TGM/CGM to prevent COVID-19 in patients at high risk for breakthrough and severe SARS-CoV-2 infection who never benefited maximally from SARS-CoV-2 vaccination and for those who have a contraindication to SARS-CoV-2 vaccines. Design: This study is a systematic review and meta-analysis. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Methods: Electronic databases (PubMed, CINAHL, Embase, medRxiv, ProQuest, Wiley online library, Medline, and Nature) were searched from 1 December 2021 to 30 November 2022 in the English language using the following keywords alone or in combination: 2019-nCoV, 2019 novel coronavirus, COVID-19, coronavirus disease 2019, SARS-CoV-2, severe acute respiratory syndrome coronavirus 2, tixagevimab, cilgavimab, combination, monoclonal, passive, immunization, antibody, efficacy, clinical trial, cohort, pre-exposure, prophylaxis, and prevention. We included studies in moderate to severe immunocompromised adults (aged ≥18 years) and children (aged ≥12 years) who cannot be vaccinated against COVID-19 or may have an inadequate response to SARS-CoV-2 vaccination. The effect sizes of the outcome of measures were pooled with 95% confidence intervals (CIs) and risk ratios (RRs). Results: Of the 76 papers that were identified, 30 articles were included in the qualitative analysis and 13 articles were included in the quantitative analysis (23 cohorts, 5 case series, 1 care report, and 1 randomized clinical trial). Studies involving 27,932 patients with high risk for breakthrough and severe COVID-19 that reported use of TGM/CGM combination were analyzed (all were adults (100%), 62.8% were men, and patients were mainly immunocompromised (66.6%)). The patients’ ages ranged from 19.7 years to 79.8 years across studies. TGM/CGM use was associated with lower COVID-19-related hospitalization rate (0.54% vs. 1.2%, p = 0.27), lower ICU admission rate (0.6% vs. 5.2%, p = 0.68), lower mortality rate (0.2% vs. 1.2%, p = 0.67), higher neutralization of COVID-19 Omicron variant rate (12.9% vs. 6%, p = 0.60), lower proportion of patients who needed oxygen therapy (8% vs. 41.2%, p = 0.27), lower RT-PCR SARS-CoV-2 positivity rate (2.1% vs. 5.8%, p < 0.01), lower proportion of patients who had severe COVID-19 (0% vs. 0.5%, p = 0.79), lower proportion of patients who had symptomatic COVID-19 (1.8% vs. 6%, p = 0.22), and higher adverse effects rate (11.1% vs. 10.7%, p = 0.0066) than no treatment or other alternative treatment in the prevention of COVID-19. Conclusion: For PrEP, TGM/CGM-based treatment can be associated with a better clinical outcome than no treatment or other alternative treatment. However, more randomized control trials are warranted to confirm our findings and investigate the efficacy and safety of TGM/CGM to prevent COVID-19 in patients at risk for breakthrough or severe SARS-CoV-2 infection