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IUCrData Mar 2024The structure of the title compound, [CHN)Ag](NO), contains subtle differences in ligand, metal, and counter-anion coordination. One quinoxaline ligand uses one of its...
The structure of the title compound, [CHN)Ag](NO), contains subtle differences in ligand, metal, and counter-anion coordination. One quinoxaline ligand uses one of its quinoxaline N atoms to bond to one silver cation. That silver cation is bound to a second quinoxaline which, in turn, is bound to a second silver atom; thereby using both of its quinoxaline N atoms. A nitrate group bonds with one of its O atoms to the first silver and uses the same oxygen to bond to a silver atom (related by symmetry to the second), thereby forming an extended network. The second nitrate group on the other silver bonds two nitrate O atoms; one silver cation therefore has a coordination number of three whereas the second has a coordination number of four. One of the quinoxaline ligands has a disordered ethyl group.
PubMed: 38586514
DOI: 10.1107/S2414314624002475 -
International Journal of Molecular... Oct 2023The healing properties of silver have been used since ancient times. The main aim of the study was to collect and review the literature on the clinical potential of... (Review)
Review
The healing properties of silver have been used since ancient times. The main aim of the study was to collect and review the literature on the clinical potential of silver, its salts and complex compounds. The second goal was to present an outline of the historical use of silver in medicine and pharmacy, taking into account the possibility of producing pharmaceutical drug forms on the premises of pharmacies. In the context of the growing resistance of microorganisms to available, widely used antibiotics, silver plays a key role. There is only one known case of bacterial resistance to silver-the strain, which naturally occurs in silver mines. The development of research in the field of coordination chemistry offers great opportunities in the design of new substances in which silver ions can be incorporated. These substances exhibit increased potency and often an extended antimicrobial spectrum. Silver-based compounds are, however, only limited to external applications, as opposed to their historic oral administration. Advanced studies of their physicochemical, microbiological, cytotoxic and genotoxic properties are ongoing and full of challenges. The improvement of the methods of synthesis gives the possibility of applying the newly synthesized compounds , as was the case with the complex of metronidazole with silver (I) nitrate. Some of these experimental efforts performed in vitro are followed with clinical trials. The third and final goal of this study was to present the possibility of obtaining an ointment under the conditions of an actual pharmacy using silver (I) salts and a ligand, both of which are active substances with antimicrobial properties.
Topics: Silver; Salts; Pharmacies; Anti-Infective Agents; Anti-Bacterial Agents; Silver Compounds; Pharmaceutical Preparations; Pharmacy
PubMed: 37958707
DOI: 10.3390/ijms242115723 -
International Dental Journal Apr 2024Silver metal and compounds have antibacterial properties, although their action's mechanisms are not fully understood. Scientists generally consider that silver disrupts... (Review)
Review
Silver metal and compounds have antibacterial properties, although their action's mechanisms are not fully understood. Scientists generally consider that silver disrupts the bacterial cell wall. It causes a structural change in the bacterial cell membrane and cytoplasm. It also stops deoxyribonucleic acid replication, resulting in inactivating enzymatic activity and cell death. The antimicrobial effect of silver-containing compounds relies on the release of bioactive silver ions. Hence, silver metal and compounds have been used in medicine to prevent infection for hundreds of years. Silver metal and compounds are also used as antibacterial agents in dentistry. Studies have shown that silver compounds are effective in the management of dental caries. Fluoride-containing silver compounds have been found in experiments to be beneficial at remineralising dental cavities. Silver diamine fluoride (SDF) can assist in preventing and arresting tooth cavities. The World Health Organization included SDF in its Model List of Essential Medicine for both adults and children in 2021. Clinicians also use SDF to manage dentine hypersensitivity as well as to inhibit growth of periodontal pathogens. However, traditional silver compounds cause tooth discolouration because of the silver-staining effect. These side effects of their applications depend on the amount applied and the frequency of application. Researchers are developing nanosilver fluoride and silver nanoparticles to overcome the staining. This review gives an overview of the antibacterial mechanism of silver compounds, namely silver nitrate, silver fluoride, SDF, silver nanoparticles, and nano silver fluoride for caries management. The outlook for the future development of silver compounds will be discussed.
Topics: Child; Humans; Cariostatic Agents; Fluorides; Dental Caries; Metal Nanoparticles; Dental Caries Susceptibility; Silver; Fluorides, Topical; Silver Compounds; Silver Nitrate; Quaternary Ammonium Compounds; Anti-Bacterial Agents
PubMed: 38008704
DOI: 10.1016/j.identj.2023.10.013 -
Cureus Nov 2023Calcium silicate-based types of cement have gained recognition in various dental applications due to their exceptional sealing capabilities, bioactivity, and minimal...
INTRODUCTION
Calcium silicate-based types of cement have gained recognition in various dental applications due to their exceptional sealing capabilities, bioactivity, and minimal adaptability. However, these materials have certain shortcomings that can lead to mechanical failures and premature degradation. The inclusion of metal ions into their structure is expected to promote their biological activity. This article focuses on the preparation and characterization of calcium silicate cement to enhance its fundamental material properties, by introducing zinc and silver while retaining its biomaterial characteristics.
AIM
This study aims to evaluate the biomedical potential of zinc and silver-impregnated bioactive calcium silicate cement.
MATERIALS AND METHODS
The calcium silicate powder was synthesized via the sol-gel method. Tetraethyl orthosilicate, calcium nitrate, silver nitrate, and zinc nitrate were sequentially added to create the bioactive calcium silicate material. The synthesized particles underwent physicochemical characterization using techniques such as scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and biological characterization through in vitro hemocompatibility assays.
RESULTS
The study's results revealed the presence of multiple crystalline phases (AgSiO, ZnSiO, CaCO) as indicated by X-ray diffraction. Raman spectra displayed vibrations associated with Si-O-Si and Zn-O bonding in the zinc and silver-infused bioactive calcium silicate. Scanning electron microscopy confirmed a mixture of spherical and sheet-like morphologies, while energy dispersive spectra confirmed the presence of elements Ca, Si, Zn, Ag, O, and C. In vitro hemocompatibility testing affirmed the material's biocompatible nature.
CONCLUSION
In conclusion, the zinc and silver-infused calcium silicate cement was successfully synthesized through an in-house procedure and demonstrated biocompatibility. The inclusion of zinc and silver, known for their osteogenic and antimicrobial properties, is anticipated to enhance the cement's biological properties and broaden its utility in dentistry. Further in vitro and in vivo investigations are imperative to validate its clinical applications and elucidate the molecular mechanisms underlying its efficacy.
PubMed: 38054157
DOI: 10.7759/cureus.48243 -
The Journal of Laryngology and Otology Sep 2023Epistaxis is one of the most common emergencies presenting to the ENT service, and silver nitrate cautery is the mainstay of epistaxis treatment in most centres... (Review)
Review
OBJECTIVE
Epistaxis is one of the most common emergencies presenting to the ENT service, and silver nitrate cautery is the mainstay of epistaxis treatment in most centres worldwide. This review aimed to ascertain the historical evidence behind current common practice.
METHOD
A review was conducted of historical published literature pertaining to epistaxis management.
RESULTS
Silver in medicine dates back to 4000 BC, with silver nitrate first being used in 69 BC. Modern medical use for epistaxis is documented in case reports over the last 200 years.
CONCLUSION
The precise origin and evidence-based practice of using silver nitrate for epistaxis is not well-established or understood. The mechanism of action is questionable; novel research of silver nitrate for this common ENT emergency presentation may be required.
Topics: Humans; Silver Nitrate; Epistaxis; Cautery
PubMed: 36165124
DOI: 10.1017/S0022215122002146 -
Heliyon Jul 2023Ulvan is a polysaccharide from green algae that shows good hydrogel film dressing characteristics. Silver nanoparticles (AgNP) can be incorporated into the hydrogel film...
Ulvan is a polysaccharide from green algae that shows good hydrogel film dressing characteristics. Silver nanoparticles (AgNP) can be incorporated into the hydrogel film to improve antibacterial properties and provide a potential burn treatment. In this study, we developed a novel hydrogel film wound dressing composed of ulvan and silver nanoparticles. Two concentrations (0.5 mM and 1 mM) of silver nitrate were used to produce ulvan-silver nanoparticles hydrogel film (UHF-AgNP0.5 and UHF-AgNP1), respectively. The physicochemical characteristics of the hydrogel films were evaluated, including particle size, zeta potential, Fourier transform infrared (FTIR), X-ray diffractometry (XRD), scanning electron microscope and energy-dispersive X-ray (SEM-EDX). Furthermore, the in vitro antimicrobial activity, and second-degree burn wound healing test were evaluated. The UHF-AgNP0.5 showed the highest antimicrobial activity compared to UHF-AgNP1 and UHF film. Meanwhile, an in vivo study using Wistar rats induced second-degree burns showed that UHF-AgNP0.5 significantly accelerated the healing process by regulating the inflammatory process, increasing re-epithelialization, and improving the vascularization process. Ulvan-silver nanoparticle hydrogel films have the ability to accelerate the healing of second-degree burns and are potential candidates for wound dressings.
PubMed: 37483826
DOI: 10.1016/j.heliyon.2023.e18044 -
Journal of Chromatography. A Jan 2024A growing interest in lacustrine alkenones as a proxy for continental paleotemperature reconstructions accompanied important methodological improvements over the past...
A growing interest in lacustrine alkenones as a proxy for continental paleotemperature reconstructions accompanied important methodological improvements over the past two decades. New gas chromatography (GC) columns were used for alkenone analysis, that drastically improved alkenone separation, especially for freshwater lakes. However, these recent advances are sometimes not sufficient in separating compounds that interfere with alkenones in the resulting chromatograms and concurrently, new chemical procedures were implemented to further clean up the samples. Here we investigate the impact of two clean-up procedures, saponification and silver-nitrate purification, on alkenone distribution, alkenone quantification, and C alkenone-based indices, including the U index. The silver-nitrate purification modified the C alkenone distribution and thus the C alkenone-based indices, especially the U index, in 6 out of the 9 studied samples by further retaining alkenones with more double bonds. These changes would result on an average error of 3 °C in reconstructed temperatures. Saponification also influenced the C alkenone distribution mainly by removing co-eluting compounds, thereby improving the quality of the results. Both saponification and purification resulted in the reduction of the C alkenone concentration by almost half. Clean-up steps should thus be used carefully, paying particular attention to any change in alkenone distribution and concentration. Limiting the use of additional clean-up steps reduces the risk of modifying the alkenone distribution.
Topics: Nitrates; Silver; Temperature; Lakes
PubMed: 38171064
DOI: 10.1016/j.chroma.2023.464576 -
Research and Reports in Urology 2023Hemorrhagic cystitis (HC) can be one of the most challenging clinical scenarios for urologists to manage. It most commonly occurs as a toxicity of pelvic radiation... (Review)
Review
Hemorrhagic cystitis (HC) can be one of the most challenging clinical scenarios for urologists to manage. It most commonly occurs as a toxicity of pelvic radiation therapy or in patients treated with the oxazaphosphorine class of chemotherapy. Successful management of HC necessitates a stepwise approach with a thorough understanding of the various treatment options. Once ensuring hemodynamic stability, conservative management includes establishing bladder drainage, manual clot evacuation, and continuous bladder irrigation through a large-bore urethral catheter. If gross hematuria persists, operative cystoscopy with bladder clot evacuation is often required. There are multiple intravesical options for treating HC, including alum, aminocaproic acid, prostaglandins, silver nitrate, and formalin. Formalin is an intravesical option that has caustic effects on the bladder mucosa and is most often reserved as a last-line intravesical treatment. Non-intravesical management tools include hyperbaric oxygen therapy and oral pentosan polysulfate. If needed, nephrostomy tube placement or superselective angioembolization of the anterior division of the internal iliac artery can be performed. Finally, cystectomy with urinary diversion is a definitive, albeit invasive, treatment option for refractory HC. While there is no standardized algorithm, treatment modalities typically progress from less to more invasive. Clinical judgement and shared decision-making with the patient are required when choosing therapies for managing HC, as success rates are variable and some treatments may have significant or irreversible effects.
PubMed: 37404838
DOI: 10.2147/RRU.S320684