جستجوی مقالات مرتبط با کلیدواژه "silver" در نشریات گروه "پزشکی"

Biological and microbial synthesis processes of nanoparticles are a safe and useful option compared to physical and chemical methods due to their compatibility with the environment and nature and their cost-effectiveness. Probiotics have beneficial effects in improving the body's immune system and are a suitable alternative in the treatment of bacterial infections. The aim of this study was the synthesis of protein nanoparticles containing silver with the probiotic bacteria Bifidobacterium breve.

First, probiotic bacteria Bifidobacterium breve were cultured and then silver albumin nanoparticles (Ag-Alb-NPs) were synthesized. X-ray diffraction (XRD), infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and dynamic light scattering (DLS) tests to investigate the physical and chemical properties of Ag-Alb-NPs used.

Ag-Alb-NPs had spherical, crystalline, semi-crystalline morphology and structure. They had O-H, N-H and C-H bonds, C=C bonds in aromatic rings and C-N bonds in amine compounds and O-H and C-H bonds in CH2 and CH3 groups, N-H, C-O bonds in the structure of C-O-C and C-OH functional groups. In addition, DLS results of albumin-silver nanoparticles and silver nanoparticles showed that they were 259 and 85.3 nm in size, respectively, and the graph was of single peak type.

In general, it was concluded that the synthesized Ag-Alb-NPs had suitable structural and physicochemical characteristics that can be used for future studies.

Among the accidents that threaten human life, burn accidents are one of the worst. Burns are the fourth most common trauma worldwide and cause death, disability, pain, and many other problems. Faster healing of burn wounds is one of the health priorities of countries and it's important as a principle in the science of treatment. This research aims to determine and compare the effectiveness of hydrogel dressings containing allantoin and silver nanoparticles in the treatment of second-degree burn wounds.

This study was designed as a randomized controlled clinical trial. A total of 86 patients were selected in the study based on the inclusion and exclusion criteria and were randomly divided into two groups: A=43 and B=43, using a block method of 4. Group A patients received hydrogel containing silver nanoparticles and allantoin with a thickness of 2 millimeters and then sterile gauze and bandage on top of it, and group B patients received the usual treatment (Vaseline gauze, 0.5% acetic acid and 1% betadine). Local treatment was performed every 48 hours, and dressing was applied after each treatment. The condition of the wounds, including the presence or absence of granulation tissue, bleeding, pain, infection, and other wound complications or healing factors, was recorded and evaluated by visiting and observing every 48 hours.

The average age in the intervention group was 10.2 years and in the control group was 9.9 years, and the difference was not statistically significant, P=0.456. 48% of the patients in the intervention group were male 52% were female, and in the control group, 44% were male and 56% were female, and the difference was not statistically significant, P=0.665. The average percentage of burns in the intervention group was 9.04% and in the control group was 9.58%, which was not statistically significant P=0.289. The type of burn in the intervention group was liquid 69% and flame 31%, and in the control group, liquid 65% and flame 34%, which was not statistically significant P=0.645.The intervention group had 55% of limbs and 45% of trunk and the control group had 63% of limbs and 37% of trunk, which difference was not statistically significant, P=0.510. In other words, the two groups were homogenous in age, sex, average burn percentage, burn mechanism, and location, and there were no significant differences. The average onset of epithelialization in the intervention group was 4.5 days (74% of patients on day 4 and 23% on day 6) and 6.4 days in the control group (60% of patients on day 6 and 30% on day 8), which was statistically significant P<0.001. The average intensity of pain in the intervention group was 5 out of 10 and in the control group was 7 out of 10, and this difference was statistically significant P<0.001.

The results of this study show that patients treated with a hydrogel dressing containing silver nanoparticles and allantoin had a statistically significant difference in the onset of wound epithelialization and pain intensity, compared to the usual dressing. This dressing can be used as a suitable alternative in the treatment of second-degree burn wounds compared to routine dressings. Therefore, offering it to the medical team, who play an essential role in the treatment of patients with burns, will reduce the length of hospitalization and the costs.

Bacterial infections are a major cause of chronic infections and mortality, and antibiotics are the preferred treatment for bacterial infections. However, studies show that widespread use of antibiotics has led to the emergence of multidrug-resistant bacterial strains. Hence, the need to develop new and alternative strategies for the production of effective drugs has become an important issue. Recently, the use of nanotechnology has been widely common in various fields. Materials in the nanoscale have unique physical and chemical properties. Silver nanoparticles have different applications and their antimicrobial properties have been confirmed in several studies. This study aimed to investigate the antibacterial properties of silver nanoparticles synthesized by berberine and Hypericum perforatum extract.

In this experimental study, the antibacterial effects of synthesized nanoparticles on standard strains of Escherichia coli [ATCC 25922], Pseudomonas aeruginosa [ATCC 27853], Klebsiella pneumoniae [ATCC 9997], and Staphylococcus aureus [ATCC 29212] were investigated. The MIC content of silver nanoparticles alone and in combination with berberine and Hypericum perforatum extract was investigated for the studied bacteria using the broth microdilution method.

The results of the evaluation of the minimum inhibitory concentration [MIC] of the synthesized compounds on the studied bacteria showed that the nanoparticles synthesized by berberine and Hypericum perforatum extract had the highest antibacterial effects. However, each of the compounds Berberine and Hypericum perforatum extract alone did not show significant antibacterial properties. The results of this study also showed that the highest inhibitory concentration of nanoparticles synthesized by berberine and Hypericum perforatum extract was related to Pseudomonas aeruginosa [0.0375 mg / ml] and the lowest inhibitory concentration was related to Enterococcus faecalis [0.185 mg/ml].

The results of the present study showed that silver nanoparticles synthesized with berberine and Hypericum perforatum extract have significant antibacterial effects. As a result, nanoparticles, including silver nanoparticles, can become one of the most important alternatives to antibiotics due to their unique properties in targeting bacteria. However, achieving definitive results requires further studies in this area.

The external fixators (pins) have many applications in orthopedic surgeries in the field of trauma. The success of clinical applications of external fixators has decreased due to their infection after orthopedic surgery. Meanwhile, the loosening of the pin embedded in the bone occurs due to the presence of bacteria and the formation of biofilm on the pin, and this infection will progress to the joint surface of the bone and the pin. Among the different techniques to improve the bone-pin interface in external fixation, coating the pins with antibacterial materials proved to be the most effective. Accordingly, the present study has focused on synthesis by sol gel method, structural, and antibacterial evaluations of Ag-FHA structure. The FESEM images and Mapping analysis confirmed the nano-scale size and homogeneous dispersion of particles in the Ag-FHA structure, respectively. In addition, the FTIR results indicated the hydroxyapatite formation in obtained structure. The XRD analysis has shown that the conversion of the amorphous phase to the crystalline phase occurred in all structures at a temperature of about 300 to 350 ° C , and the formation of the HA phase is increased and completed at 600 ° C. The antibacterial study was done by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) determination. The obtained results showed that the Ag 0.2-FHA could significantly inhibit the growth of Staphylococcus aureus and Escherichia coli.

Fixators are the basic equipment for fractures that are divided into two categories, internal and external. The success of clinical applications of external fixators has decreased due to their infection after orthopedic surgery. Meanwhile, the loosening of the pin embedded in the bone occurs due to the presence of bacteria and the formation of biofilm on the pin, and this infection will progress to the joint surface of the bone and the pin. Natural elements with antibacterial activity attract much attention as a coating on implants surface in orthopedics surgery. This article reviewed common elements with antibacterial activity that can be loaded into the HA structure as a coating for improving their clinical efficiency. Substitution ions such as copper, silver, magnesium, strontium, zinc, silicon, and fluoride in an appetite network can stimulate bone formation at the fracture site. In this article, common antibacterial ions in the form of loading -HA have been investigated as coating orthopedic fixators. good strength and antibacterial activity presented for silver, and corrosion resistance and high porosity are advantages of copper. Also, magnesium with favorable biocompatibility and biodegradability, zinc with high strength, and silicon and fluorine with high flexibility, favorable mechanical properties, and corrosion resistance are introduced. Among the mentioned elements, silver and fluoride, due to having more favorable antibacterial activity and excellent bone regeneration, can be more suitable candidates for loading in the HA structure with the application of the coating on the orthopedic surface.

Considering the increasing use of silver nanoparticles in various products, including industrial and medical products, serious worries have been created regarding the potential dangers of silver nanoparticles. This study was conducted to determine the effect of silver nanoparticles on the kidney tissues of quercetin-treated NMRI rats.

In this experimental study, 24 adult male NMRI rats were randomly divided into 4 groups of 6. The groups included the control group, the silver nanoparticles group (500 mg/kg/bw), the quercetin group (50 mg/kg/bw), and the silver nanoparticles (500 mg/kg/bw) + quercetin (50 mg/kg/bw) group. Silver nanoparticles were fed orally on a daily basis for 35 days. Quercetin was injected intraperitoneally on a daily basis for 42 days. At the end of the study, after taking blood from the rats, the dissection, tissue passaging, and Heidenhain’s Azan staining stages were carried out. The total volumes of the kidney, cortex and medulla, renal corpuscle, and glomerulus were evaluated by a stereological method. A qualitative assessment of apoptotic cells was performed using the tunnel method. The amount of malondialdehyde (MDA) in blood serum was specified as an indicator of lipid peroxidation by the Buege and Aust method.

Comparing the body weight and kidneys, and the total kidney, cortex, and medulla volumes showed no statistically significant difference between the silver nanoparticles group and the control group. The silver nanoparticles group showed a significant increase in the total mean renal corpuscle volume, glomerular volume, tuft volume, Bowman’s capsule membrane volume, and the amount of MDA compared to the control group (P<0.05). Also, a statistically significant reduction was observed in the silver nanoparticles group in the total mean volume of Bowman’s capsule and capillary spaces compared to the control group (P<0.05). Quercetin could reduce the detrimental effects of silver nanoparticles on kidney cells as much as the control group; however, apoptosis was not shown in kidney cells in the group treated with quercetin. Assessing the cells in the silver nanoparticles group indicated the creation of apoptosis. The amount of serum MDA in the silver nanoparticles group showed a statistically significant increase compared to other groups (P<0.05).

The results of this study demonstrated that quercetin could reduce the detrimental effects of silver nanoparticles on kidney cells as much as the control group.

Silver nanoparticles are produced in large quantities in the industry and have estrogenic activities and toxic effects on different organs. This study was conducted to determine the effect of silver nanoparticles on the ovarian tissue of NMRI rats treated with alpha lipoic acid.

In this experimental study, 24 female NMRI rats were randomly divided into 4 groups of 6. The groups included the control group, oral silver nanoparticles (500 mg/kg of body weight), injected alpha lipoic acid (100 mg/kg of body weight), and silver nanoparticles (500 mg/kg of body weight) plus alpha lipoic acid (100 mg/kg body weight). The treatment was performed for 28 days. After the treatment period, blood sampling was performed from the rats’ hearts to analyze biochemical parameters (malondialdehyde, estrogen, progesterone, and total antioxidant capacity using the ferric reducing ability of plasma (FRAP) method). By dissecting the rats, the left ovaries were removed, fixed, molded, and cut, tissue passaging was performed, and the ovaries were stained using the hematoxylin-eosin method. Then, the ovarian tissue was evaluated by different stereological methods.

The total mean ovarian volume, the cortex volume, the medulla volume, and the corpus luteum volume, and the total number of primordial, primary, secondary, and Graafian follicles were significantly reduced in the silver nanoparticles group compared to the control group (P<0.05). The simultaneous administration of alpha lipoic acid and silver nanoparticles compensated for the adverse effects of silver nanoparticles on the above parameters. On the other hand, the mean number of different types of follicles in the rats treated with alpha lipoic acid significantly increased compared to the control group (P<0.05). A statistically significant reduction was observed in the measurement of estrogen and progesterone hormones in the serum of the silver nanoparticles group compared to the control group (P<0.05). Moreover, in assessing the antioxidant capacity of the serum of the group treated simultaneously with silver nanoparticles + alpha lipoic acid, a statistically significant increase was observed compared to the group treated with silver nanoparticles (P<0.05).

Silver nanoparticles can have adverse effects on the structure of the ovary and its components, and alpha lipoic acid can largely compensate for these detrimental effects.

Nanoparticles and nanocomposites in low concentrations can be a suitable alternative to antibiotics. In this study, for the first time, silver-zinc oxide nanocomposites were synthesized from the cellulose of Barhi date palm (Phoenix dactylifera L.) seeds.

In this study, the chemical compounds of Berhi date palm seed extract (such as phenols, flavonoids, and ascorbic acid) were first assessed, and silver-zinc oxide nanocomposites were synthesized. The properties of the synthesized nanocomposites were evaluated using different spectroscopy and microscopy techniques. The antibacterial activity of the extract and silver-zinc oxide nanocomposites was investigated against standard strains of Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. The cytotoxicity of the extract and nanocomposites against breast cancer cells MCF-7 and normal cells MCF-10A were finally evaluated.

In the extract, there were high concentrations of flavonoids and phenols. Based on scanning electron microscopy and transmission electron microscopy, the size of synthesized nanocomposites was 20±5 nm with a spherical shape. The diameter of the inhibition zones was 21.3±0.5 mm and 19.4±0.7 mm for Klebsiella pneumoniae and Escherichia coli, respectively. According to the MTT assay results, the nanocomposites were more cytotoxic to MCF-7 breast cancer cells than normal cells MCF-10A.

The synthesized zinc oxide-silver nanocomposites have antibacterial and anticancer properties with fewer side effects and significant efficacy, which can be used as a potential therapy in the future.

The aim of this study was to determine the effectiveness of hydrocolloid dressings containing silver in the treatment of wounds in the donor area of partial thickness skin seizures.

This randomized clinical trial was conducted on 42 patients who needed partial thickness skin grafts for skin defect reconstruction. After removing the skin graft, the patients were randomly assigned to two groups of hydrocolloid dressing containing silver with Aquacel Ag brand (intervention group) and traditional dressing group (control group). Patients were visited on days 3, 7, 5 and 7, 14 and 21. In each visit, the frequency of dressing change, wound infection, pain during dressing change, the rate and speed of the epithelialization process, and the scar of the wound site were also compared in the two groups at the end of the sixth month. The collected data were analyzed using SPSS version 24 software.

The results showed that there was a statistically significant difference between the average number of times the need for dressing, the degree of epithelialization of the wound, in the two groups of hydrocolloid dressing with silver and traditional dressing (P-value &lt; 0.05); However, there was no statistically significant difference between the mean prevalence of infection, pain during dressing change, vascularity, pigmentation and scar thickness in the two groups of hydrocolloid dressing with silver and traditional dressing (P-value &lt; 0.05).

Overall, the results of this research showed that Aquacel Ag is a safe and effective method for managing the wound in the donor area of partial thickness skin grafts.