Modulating metal-organic framework’s(MOF)crystallinity and size using a polymer,in conjunction with a high surface area of layered double hydroxide,yields an effective strategy for concurrently enhancing the electroc...Modulating metal-organic framework’s(MOF)crystallinity and size using a polymer,in conjunction with a high surface area of layered double hydroxide,yields an effective strategy for concurrently enhancing the electrochemical and photocatalytic performance.In this study,we present the development of an optimized nanocomposite,denoted as 0.5PVP/ZIF-67,developed on AZ31 magnesium alloy,serving as an efficient and durable multifunctional coating.This novel strategy aims to enhance the overall performance of the porous coating through the integration of microarc oxidation(MAO),ZnFe LDH backbone,and ZIF-67 formation facilitated by the addition of polyvinylpyrrolidone(PVP),resulting in a three-dimensional,highly efficient,and multifunctional material.The incorporation of 0.5 g of PVP proved to be effective in the size modulation of ZIF-67,which formed a corrosion-resistant top layer,improving the total polarization resistance(R_(p)=8.20×10^(8)).The dual functionality exhibited by this hybrid architecture positions it as a promising candidate for mitigating environmental pollution,degrading 97.93%of Rhodamine B dye in 45 min.Moreover,the sample displayed exceptional degradation efficiency(96.17%)after 5 cycles.This study illuminates the potential of nanocomposites as electrochemically stable and photocatalytically active materials,laying the foundation for the advancements of next-generation multifunctional frameworks.展开更多
The objective of this study was to prepare and characterize paclitaxel-polyvinylpyrrolidone (PTX-PVP) solid dispersions with the intention of improving its solubility and dissolution properties. The PTX-PVP solid di...The objective of this study was to prepare and characterize paclitaxel-polyvinylpyrrolidone (PTX-PVP) solid dispersions with the intention of improving its solubility and dissolution properties. The PTX-PVP solid dispersion systems were prepared by solvent method. The release rate ofpaclitaxel was determined from dissolution studies and the physicochemical properties of solid dispersion were investigated by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The cytotoxicities ofpaclitaxel in solid dispersion to the SKOV-3 cells were assayed by a SRB staining method. The results showed that the solubility and dissolution rate of paclitaxel were significantly improved in solid dispersion system compared with that of the pure drug and physical mixture. The results of DSC and PXRD showed that the paclitaxel in solid dispersion was amorphous form. No paclitaxel crystals in the solid dispersions was found during SEM analysis. Cytotoxicity study suggested that the inhibitory rates of PTX-PVP solid dispersion to SKOV-3 cells were higher than that of pure paclitaxel. The solubility and dissolution of paclitaxel were improved by solid dispersion technique. In vitro cytotoxicity of paclitaxel in solid dispersion was higher than that of pure drug.展开更多
[Objective] The aim of this study is to investigate the bacteriostatic and bactericidal efficacy of povidone iodine as one kind of disinfectants for aquaculture on Aeromonas.[Method] With the standard strain of Aeromo...[Objective] The aim of this study is to investigate the bacteriostatic and bactericidal efficacy of povidone iodine as one kind of disinfectants for aquaculture on Aeromonas.[Method] With the standard strain of Aeromonas ATCC7966 and the Aeromonas strains isolated from diseased fish or aquatic environment as the tested strains,the bacteriostatic and bactericidal efficacy of povidone iodine was studied by double broth dilution method.[Result] The povidone iodine could inhibit the growth of Aeromonas strains at lower concentration,and killed Aeromonas strains at higher concentration.The minimum bacteriostatic concentration(MIC) of povidone iodine on Aeromonas sp.T1,Aeromonas sp T2 and Aeromonas sp.T4 was 125.00 mg/L,and the minimum bactericidal concentration(MBC) was 4.00 g/L.Whereas,the minimum bacteriostatic concentration(MIC) of povidone iodine on ATCC7966,Aeromonas sp.T3,Aeromonas sp T5 and Aeromonas sp.T6 was 250.00 mg/L,and the minimum bactericidal concentration(MBC) was 8.00 g/L.[Conclusion] This study provides certain basis for reasonable application of povidone iodine.展开更多
Aim The objective of this study was to prepare and characterize quercetin-polyvinylpyrrolidone (Qurc-PVP) solid dispersion with the intention of improving its dissolution properties, Methods Qurc-PVP sclid dispersio...Aim The objective of this study was to prepare and characterize quercetin-polyvinylpyrrolidone (Qurc-PVP) solid dispersion with the intention of improving its dissolution properties, Methods Qurc-PVP sclid dispersion was prepared by solvent method. The release rate of quercetin was determined from dissolution studies and the physicochemical properties of solid dispersion were investigated by differential scanning calorimetry (DSC), infrared spectroscopy (IR), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). Results The results showed that the dissolution rate of quercetin was significantly improved by solid dispersion compared to that of the pure drug and physical mixture, Solubility studies revealed a markedly increase in the solubility of quercetin. The results of DSC and PXRD showed that the quercetin in solid dispersion was amorphous form. From SEM analysis, there was no quercetin crystal observed in the solid dispersions. Conclusion The solubility and dissolution of quercetin were improved by solid dispersion technique.展开更多
Tb(Ⅲ )-trimesic acid (TMA) luminescent complexes were synthesized in the polyvinylpyrrolidone (PVP) matrix. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and fourie...Tb(Ⅲ )-trimesic acid (TMA) luminescent complexes were synthesized in the polyvinylpyrrolidone (PVP) matrix. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and fourier-transform infrared spectroscopy (FT-IR) indicated that its chemical constitution is PVP/Tb(MTA)· 4H2O. The XRD patterns showed that the complex is a new kind of crystal. The TEM image indicates that the complex is rod shaped. The rod diameter is about 200 nm, and the length ranges from hundred of nanometer to a few micrometers. In addition, the dispersity is better. TG-DTA curves indicate that the complex is thermally stable before 463℃. Photoluminescence analysis indicates that the complex emits Tb^3+ characteristic luminescence under ultraviolet excitation.展开更多
The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being bot...The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and guest polymer in solution.The intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent interactions.It was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in solution.The viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_c.The effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.展开更多
Among the different bioprinting techniques,the drop-on-demand(DOD)jetting-based bioprinting approach facilitates contactless deposition of pico/nanoliter droplets ofmaterials and cells for optimal cell–matrix and cel...Among the different bioprinting techniques,the drop-on-demand(DOD)jetting-based bioprinting approach facilitates contactless deposition of pico/nanoliter droplets ofmaterials and cells for optimal cell–matrix and cell–cell interactions.Although bioinks play a critical role in the bioprinting process,there is a poor understanding of the influence of bioink properties on printing performance(such as filament elongation,formation of satellite droplets,and droplet splashing)and cell health(cell viability and proliferation)during the DOD jetting-based bioprinting process.An inert polyvinylpyrrolidone(PVP360,molecular weight=360 kDa)polymerwas used in this study to manipulate the physical properties of the bioinks and investigate the influence of bioink properties on printing performance and cell health.Our experimental results showed that a higher bioink viscoelasticity helps to stabilize droplet filaments before rupturing from the nozzle orifice.The highly stretched droplet filament resulted in the formation of highly aligned“satellite droplets,”which minimized the displacement of the satellite droplets away from the predefined positions.Next,a significant increase in the bioink viscosity facilitated droplet deposition on the wetted substrate surface in the absence of splashing and significantly improved the accuracy of the deposited main droplet.Further analysis showed that cell-laden bioinks with higher viscosity exhibited higher measured average cell viability(%),as the presence of polymer within the printed droplets provides an additional cushioning effect(higher energy dissipation)for the encapsulated cells during droplet impact on the substrate surface,improves the measured average cell viability even at higher droplet impact velocity and retains the proliferation capability of the printed cells.Understanding the influence of bioink properties(e.g.,bioink viscoelasticity and viscosity)on printing performance and cell proliferation is important for the formulation of new bioinks,and we have demonstrated precise DOD deposition of living cells and fabrication of tunable cell spheroids(nL–μL range)using multiple types of cells in a facile manner.展开更多
Smart material can be defined as a material that can dock or convert energy between physical domains or as a material that can generate a response, in their characteristics, properties or geometries, when submitted to...Smart material can be defined as a material that can dock or convert energy between physical domains or as a material that can generate a response, in their characteristics, properties or geometries, when submitted to an external stimulus, for example, to heat, water presence, light, etc. In this paper, the second definition will be approached. Hydrogels are crosslinked materials that can absorb a big amount of water. They generally can be considered as smart materials once they exhibit sensibility to external stimuli like to pH variation, as will be approached in this paper. Thus, chitosan/polyvinylpyrrolidone hydrogels of three different ratios between these two polymers (1:1, 7:3 and 3:7) were synthesized and putted in aqueous solution with different pHs. The pH was adjusted adding drops of NaOH and HCl, slowly. After the collection of results and in order to understand the phenomena in a visual way, models of the molecules were also elaborated using the Avogadro software. Therefore, it was possible to realize that the greater the ratio of chitosan in the hydrogel, the greater its sensitivity to pH. Such characteristic is associated with the amino (-NH2) groups in it structure, which are capable of protonating and deprotonating (depending of the pH), generating charges under the chemical structure of the material, which will expand its volume in order to minimize the repulsion between charges. In addition, it was also noted that the hydrogel expansion is inversely proportional to the pH increase. By practical tests, it was possible to conclude that chitosan/PVP hydrogel with ratio 7:3 is the most interesting once it presented a greater quantity of chitosan in its composition, what implied in more rigidity than the others and greater ease of handling, resulting in more reliable results. This hydrogel also showed higher sensitivity to pH.展开更多
Objective: The ototoxicity of povidone-iodine has been documented in animal studies. However, there is limited evidence of these ototoxic effects in humans. This is the first report to show the ototoxic effects of pov...Objective: The ototoxicity of povidone-iodine has been documented in animal studies. However, there is limited evidence of these ototoxic effects in humans. This is the first report to show the ototoxic effects of povidoneiodine in a human subject.Patient: A 36-year-old woman came to our hospital complaining of left unilateral persistent hearing loss. One month before presentation, her child had accidentally struck her on her left ear. She applied approximately three drops of povidone-iodine(10% weight/volume) into her left auditory canal. Immediately after application, she felt severe pain and vertigo. An audiogram revealed severe left unilateral sensorineural hearing loss. Magnetic resonance imaging showed mild enhancement of the left vestibule and basal turn of the left cochlea.Conclusions: Even a single application of povidone-iodine could cause significant hearing loss and disequilibrium. It should, therefore, be used with caution.展开更多
AIM: To evaluate the clinical characteristics of adenoviral keratoconjunctivitis, the management modalities, as well as the incidence of subepithelial corneal infiltrates(SEI).METHODS: Patients with characteristic cli...AIM: To evaluate the clinical characteristics of adenoviral keratoconjunctivitis, the management modalities, as well as the incidence of subepithelial corneal infiltrates(SEI).METHODS: Patients with characteristic clinical symptoms and signs, who presented to our clinic within the first week of symptoms and received the diagnosis of adenoviral keratoconjunctivitis between January 2013 and April 2016, were included in the study. A total of 211 patients were included in the study. Patients were evaluated for the incidence of clinical signs, late complications, management preferences, and the effect of diluted povidone-iodine(d-PVP-I) 2%. RESULTS: Patients’ mean age was 33.03±14.76 y. We observed an increase in the number of cases according to the years. At presentation and/or early follow-up, the clinical signs were conjunctival hyperemia(100%), conjunctival follicules(79.1%), edema of the eyelids(39.3%), chemosis(16.1%), pseudomembrane formation(16.6%), and corneal epitheliopathy(29.9%). During late follow-up 13.3% patients developed conjunctival subepithelial fibrosis, and 39.8% developed SEI. A significant decrease in the incidence of SEI development was observed in patients who used d-PVP-I 2%(P=0.032;33.3% vs 45.9%, respectively in patients who received d-PVP-I 2% and who did not).CONCLUSION: Adenoviral keratoconjunctivitis has a tremendous effect on patient’s comfort and abilities in short-term. Additionally, almost half of the patients develop visual problems related to SEI. According to our clinical experience, using d-PVP-I 2% in the first days of adenoviral keratoconjunctivitis might be helpful in reducing the risk of SEI as a complication.展开更多
Interactions of polyvinylpyrrolidone (PVP) with metal chlorides (MgCl 2 , CaCl 2 , KCl and BaCl 2 ) have been investigated by viscometric and spectrophotometric techniques in aqueous solutions. Intrinsic viscosity [η...Interactions of polyvinylpyrrolidone (PVP) with metal chlorides (MgCl 2 , CaCl 2 , KCl and BaCl 2 ) have been investigated by viscometric and spectrophotometric techniques in aqueous solutions. Intrinsic viscosity [η] of (PVP) has shown a discontinuity with varying concentration of metal chlorides. The decreasing order of effectiveness of cation is K 1+ > Ca 2+ > Mg 2+ > Ba 2+ for poly(vinylpyrrolidone) solution. Changes in the absorption spectra of the cosolutes were observed in the presence of PVP in the lower limit of the UV-visible region i.e. 200-210 nm. These changes were attributed to interaction of PVP molecules with the cosolute molecules. As the concentration of the cosolute increased, a red shift in the peaks was observed, indicating an increase in interaction between PVP and cosolutes.展开更多
Background: Surgical site infection (SSI) is a dreaded nightmare for the Orthopaedic surgeon. Preoperative skin cleaning with antiseptics has been shown to reduce the microbial burden of the skin and results in reduce...Background: Surgical site infection (SSI) is a dreaded nightmare for the Orthopaedic surgeon. Preoperative skin cleaning with antiseptics has been shown to reduce the microbial burden of the skin and results in reduced incidence of SSI. However, the ideal skin cleaning agent remains to be established. Aim: To compare the efficacy of Povidone-Iodine/Povidone-Iodine (PI-PI) combination with that of Chlorhexidine-Gluconate/Alcohol (CG-A) combination in re-ducing SSI in Orthopaedic surgeries. Methods: This was a prospective, randomized, double-blinded, controlled study. Subjects that met the selection criteria and gave consent were randomized into PI-PI group (test group) and the CG-A group (control group). Both the patients and the assessors for SSI were blinded to the group a participant belongs. Blocking was done on the type of surgery to cancel the confounding effect of surgery type on SSI. Standard perioperative protocols were applied to both groups. Assessment for features of SSI was done on the 3rd day, 7th day, 14th day, 6th week and 12th-week postoperative period. The diagnosis of SSI was made based on the Centers for Disease and Control (CDC) guidelines. Results: We recruited 124 patients for this study, 62 males and 54 females. The mean age of the subjects was 37.5 years (SD = 14.7 years). Sixty-two subjects were randomized into each group. There was no significant difference in the distribution of the genders in the study arms. Other possible confounders such as duration of hospital stay, use of drains, the surgeon involved and age were evenly distributed in the two groups. Eight patients did not complete the study. The overall incidence of SSI in the study was 2.6%. Subjects in the control group had an SSI of 3.4% while those in the PI-PI group had a rate of 1.8%;however, this was not significant, p = 0.579. Conclusion: Both CG-A and PI-PI combinations are equally efficacious as preoperative skin antiseptic in Orthopaedic implant surgeries.展开更多
AIM:To investigate the effects of diquafosol sodium(DQS)for dry eye model induced with povidone-iodine(PI)solution.METHODS:Ten Sprague Dawley rats as the control group.Thirty Sprague Dawley rats were used to establish...AIM:To investigate the effects of diquafosol sodium(DQS)for dry eye model induced with povidone-iodine(PI)solution.METHODS:Ten Sprague Dawley rats as the control group.Thirty Sprague Dawley rats were used to establish the dry eye model with stimulation of 10 g/L PI for 14d,then divided rats into three groups:dry eye group with no treatment(DED group,n=10);phosphate buffer saline treated group(PBS group,n=10);diquafosol treated group(DQS group,n=10).Clinical changes were observed by tear production test,fluorescein staining,tear breakup time(TBUT)test,corneal confocal microscope and ocular surface comprehensive analyzer.Eyeballs were collected on day 10 of treatment for hematoxylin-eosin(HE),periodic acid-Schiff(PAS),and alcian blue staining.TUNEL assay,polymorphonuclear(PMN)and mucin 1(MUC1)immunofluorescence were performed and corneal ultrastructural changes were detected by electron microscopy.RESULTS:Compared with DED and PBS groups,tear production(7.26±0.440 vs 4.07±0.474 mm;7.26±0.440 vs 3.74±0.280 mm;all P<0.01)and TBUT(7.37±0.383s vs 1.49±0.260s;7.37±0.383s vs 1.42±0.437s;all P<0.01)were significantly increased in DQS group.HE,PAS,and alcian blue staining and MUC1 immunofluorescence showed mucins and conjunctival goblet cells density(8.45±0.718 vs 5.21±0.813 cells/0.1 mm^(2);8.45±0.718 vs 5.36±0.615 cells/0.1 mm^(2);all P<0.01)increased in DQS group.Confocal microscopy,PMN immunofluorescence and TUNEL staining showed inflammatory infiltration and corneal epithelial cells apoptosis decreased in DQS group.The increased number of microvilli in corneal epithelial and the recovered cell junction were observed in DQS group.CONCLUSION:PI instillation can induce goblet cells and mucin loss,epithelial cell apoptosis and inflammation,which are consistent with the pathological manifestations of dry eye.Diquafosol can repair the ocular surface damage caused by PI,reduce corneal inflammation,inhibit corneal epithelial cell apoptosis,promote mucin secretion and maintain tear film stability.展开更多
In this paper, ultrafine nitrogen-doped TiO2 photocatalyst with enhanced photocatalytic water-splitting properties was successfully fabricated via a solvothermal method. Herein, polyvinylpyrrolidone(PVP) was used as...In this paper, ultrafine nitrogen-doped TiO2 photocatalyst with enhanced photocatalytic water-splitting properties was successfully fabricated via a solvothermal method. Herein, polyvinylpyrrolidone(PVP) was used as both nitrogen source and stabilizer. The enhancement in water-splitting process can be attributed to the doping of element nitrogen, which could supply an intermediate energy level and promote the separation of photo-excited holes and electrons. Moreover, this paper provides a new application of high-molecular polymer to synthesize solar-driven water-splitting photocatalysts.展开更多
Surgical Site Infections (SSIs) remain a prevalent issue in healthcare. An average of 2% to 4% of all Total Knee Arthroplasties (TKA/TKR) result in a Prosthetic Joint Infection (PJI) (Ashraf et al. , 2018). These surg...Surgical Site Infections (SSIs) remain a prevalent issue in healthcare. An average of 2% to 4% of all Total Knee Arthroplasties (TKA/TKR) result in a Prosthetic Joint Infection (PJI) (Ashraf et al. , 2018). These surgical site infections cause significant distress to the patient and require extended courses of antibiotic treatment and revision surgery of the infected joint. SSIs also reduce financial reimbursement to the surgery facility and affect the performing surgeon’s performance scores. To prevent surgical infection, healthcare facilities have implemented various screening or decolonization methods to prevent surgical infection to may cause infection. Various treatment methods exist for managing MRSA preoperatively which include Povidone Iodine (PI) application as a universal decolonization method and/or screening every patient pre-operatively for MRSA and treating MRSA-positive patients with Mupirocin ointment. Both interventions are well-established in the literature. At the author’s facility, the elective TKR populations were analyzed while each intervention was implemented. In 2019 TKR patients underwent MRSA swabbing and testing and in 2021 PI decolonization was the decolonization method of choice. The study revealed that MRSA testing and swabbing were better at reducing SSI related to MRSA than Povidone Iodine decolonization.展开更多
Doxorubicin-loaded nanoparticles, using doxorubicin (ADM) as model drug and vinylpyrrolidone as matrix, were prepared by inverse emulsion polymerization in the paper. The nanoparticles were characterized by telescop...Doxorubicin-loaded nanoparticles, using doxorubicin (ADM) as model drug and vinylpyrrolidone as matrix, were prepared by inverse emulsion polymerization in the paper. The nanoparticles were characterized by telescope electron microscopy (TEM), laser light scattering technique (LLS) and infrared spectrum (IR). LLS test showed that the optimal prepared ADM-loaded nanoparticles had an average size 18.8nm and a narrow size distribution between 15nm and 32nm, which was consistent with the result obtained by TEM. And 1R results indicated that the nanoparticles consisted of ADM and polyvinylpyrrolidone (PVP).展开更多
Background: Povidone-iodine (PVI) irrigation is currently used to decrease the frequency of postoperative surgical site infections. Ethanol (EtOH) is sometimes applied to prevent local recurrence after curettage of be...Background: Povidone-iodine (PVI) irrigation is currently used to decrease the frequency of postoperative surgical site infections. Ethanol (EtOH) is sometimes applied to prevent local recurrence after curettage of benign bone tumors. However, the effects of PVI and EtOH on surrounding soft tissue and on bone union are unclear. The purpose of this study was to determine whether PVI or EtOH adversely affects the cancellous bone healing of the osteotomy site at the proximal tibia in rats. Methods: A cancellous bone osteotomy was performed at the right proximal tibia in 4-month-old, female, Sprague Dawley rats. Vehicle, 10% PVI, or 95% EtOH-soaked gauze was inserted into the osteotomy site and maintained for 6 minutes. The rats were euthanized 2 or 4 weeks after the osteotomy. Results: Two weeks after treatment, the bone union rate was significantly higher in the vehicle group than in the PVI group and the EtOH group (p < 0.001). However, the bone union rate was not significantly different between the PVI and EtOH groups. There was no significant difference among the three groups in the bone union rate 4 weeks after treatment. Conclusion: PVI or EtOH delayed bone union of the cancellous bone osteotomy site of the proximal tibia in the early phase (2 weeks), but not at 4 weeks, in rats.展开更多
基金supported by the National Research Foundation of Korea(NRF)funded by the Korean government(MSIT)(No.2022R1A2C1006743).
文摘Modulating metal-organic framework’s(MOF)crystallinity and size using a polymer,in conjunction with a high surface area of layered double hydroxide,yields an effective strategy for concurrently enhancing the electrochemical and photocatalytic performance.In this study,we present the development of an optimized nanocomposite,denoted as 0.5PVP/ZIF-67,developed on AZ31 magnesium alloy,serving as an efficient and durable multifunctional coating.This novel strategy aims to enhance the overall performance of the porous coating through the integration of microarc oxidation(MAO),ZnFe LDH backbone,and ZIF-67 formation facilitated by the addition of polyvinylpyrrolidone(PVP),resulting in a three-dimensional,highly efficient,and multifunctional material.The incorporation of 0.5 g of PVP proved to be effective in the size modulation of ZIF-67,which formed a corrosion-resistant top layer,improving the total polarization resistance(R_(p)=8.20×10^(8)).The dual functionality exhibited by this hybrid architecture positions it as a promising candidate for mitigating environmental pollution,degrading 97.93%of Rhodamine B dye in 45 min.Moreover,the sample displayed exceptional degradation efficiency(96.17%)after 5 cycles.This study illuminates the potential of nanocomposites as electrochemically stable and photocatalytically active materials,laying the foundation for the advancements of next-generation multifunctional frameworks.
文摘The objective of this study was to prepare and characterize paclitaxel-polyvinylpyrrolidone (PTX-PVP) solid dispersions with the intention of improving its solubility and dissolution properties. The PTX-PVP solid dispersion systems were prepared by solvent method. The release rate ofpaclitaxel was determined from dissolution studies and the physicochemical properties of solid dispersion were investigated by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The cytotoxicities ofpaclitaxel in solid dispersion to the SKOV-3 cells were assayed by a SRB staining method. The results showed that the solubility and dissolution rate of paclitaxel were significantly improved in solid dispersion system compared with that of the pure drug and physical mixture. The results of DSC and PXRD showed that the paclitaxel in solid dispersion was amorphous form. No paclitaxel crystals in the solid dispersions was found during SEM analysis. Cytotoxicity study suggested that the inhibitory rates of PTX-PVP solid dispersion to SKOV-3 cells were higher than that of pure paclitaxel. The solubility and dissolution of paclitaxel were improved by solid dispersion technique. In vitro cytotoxicity of paclitaxel in solid dispersion was higher than that of pure drug.
基金Supported by Startup Program for Doctors of Yangtze University(801200010110)~~
文摘[Objective] The aim of this study is to investigate the bacteriostatic and bactericidal efficacy of povidone iodine as one kind of disinfectants for aquaculture on Aeromonas.[Method] With the standard strain of Aeromonas ATCC7966 and the Aeromonas strains isolated from diseased fish or aquatic environment as the tested strains,the bacteriostatic and bactericidal efficacy of povidone iodine was studied by double broth dilution method.[Result] The povidone iodine could inhibit the growth of Aeromonas strains at lower concentration,and killed Aeromonas strains at higher concentration.The minimum bacteriostatic concentration(MIC) of povidone iodine on Aeromonas sp.T1,Aeromonas sp T2 and Aeromonas sp.T4 was 125.00 mg/L,and the minimum bactericidal concentration(MBC) was 4.00 g/L.Whereas,the minimum bacteriostatic concentration(MIC) of povidone iodine on ATCC7966,Aeromonas sp.T3,Aeromonas sp T5 and Aeromonas sp.T6 was 250.00 mg/L,and the minimum bactericidal concentration(MBC) was 8.00 g/L.[Conclusion] This study provides certain basis for reasonable application of povidone iodine.
文摘Aim The objective of this study was to prepare and characterize quercetin-polyvinylpyrrolidone (Qurc-PVP) solid dispersion with the intention of improving its dissolution properties, Methods Qurc-PVP sclid dispersion was prepared by solvent method. The release rate of quercetin was determined from dissolution studies and the physicochemical properties of solid dispersion were investigated by differential scanning calorimetry (DSC), infrared spectroscopy (IR), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). Results The results showed that the dissolution rate of quercetin was significantly improved by solid dispersion compared to that of the pure drug and physical mixture, Solubility studies revealed a markedly increase in the solubility of quercetin. The results of DSC and PXRD showed that the quercetin in solid dispersion was amorphous form. From SEM analysis, there was no quercetin crystal observed in the solid dispersions. Conclusion The solubility and dissolution of quercetin were improved by solid dispersion technique.
基金Project supported bythe Science Fund of Education Office in Jilin Province (200468)
文摘Tb(Ⅲ )-trimesic acid (TMA) luminescent complexes were synthesized in the polyvinylpyrrolidone (PVP) matrix. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and fourier-transform infrared spectroscopy (FT-IR) indicated that its chemical constitution is PVP/Tb(MTA)· 4H2O. The XRD patterns showed that the complex is a new kind of crystal. The TEM image indicates that the complex is rod shaped. The rod diameter is about 200 nm, and the length ranges from hundred of nanometer to a few micrometers. In addition, the dispersity is better. TG-DTA curves indicate that the complex is thermally stable before 463℃. Photoluminescence analysis indicates that the complex emits Tb^3+ characteristic luminescence under ultraviolet excitation.
文摘The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and guest polymer in solution.The intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent interactions.It was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in solution.The viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_c.The effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.
文摘Among the different bioprinting techniques,the drop-on-demand(DOD)jetting-based bioprinting approach facilitates contactless deposition of pico/nanoliter droplets ofmaterials and cells for optimal cell–matrix and cell–cell interactions.Although bioinks play a critical role in the bioprinting process,there is a poor understanding of the influence of bioink properties on printing performance(such as filament elongation,formation of satellite droplets,and droplet splashing)and cell health(cell viability and proliferation)during the DOD jetting-based bioprinting process.An inert polyvinylpyrrolidone(PVP360,molecular weight=360 kDa)polymerwas used in this study to manipulate the physical properties of the bioinks and investigate the influence of bioink properties on printing performance and cell health.Our experimental results showed that a higher bioink viscoelasticity helps to stabilize droplet filaments before rupturing from the nozzle orifice.The highly stretched droplet filament resulted in the formation of highly aligned“satellite droplets,”which minimized the displacement of the satellite droplets away from the predefined positions.Next,a significant increase in the bioink viscosity facilitated droplet deposition on the wetted substrate surface in the absence of splashing and significantly improved the accuracy of the deposited main droplet.Further analysis showed that cell-laden bioinks with higher viscosity exhibited higher measured average cell viability(%),as the presence of polymer within the printed droplets provides an additional cushioning effect(higher energy dissipation)for the encapsulated cells during droplet impact on the substrate surface,improves the measured average cell viability even at higher droplet impact velocity and retains the proliferation capability of the printed cells.Understanding the influence of bioink properties(e.g.,bioink viscoelasticity and viscosity)on printing performance and cell proliferation is important for the formulation of new bioinks,and we have demonstrated precise DOD deposition of living cells and fabrication of tunable cell spheroids(nL–μL range)using multiple types of cells in a facile manner.
文摘Smart material can be defined as a material that can dock or convert energy between physical domains or as a material that can generate a response, in their characteristics, properties or geometries, when submitted to an external stimulus, for example, to heat, water presence, light, etc. In this paper, the second definition will be approached. Hydrogels are crosslinked materials that can absorb a big amount of water. They generally can be considered as smart materials once they exhibit sensibility to external stimuli like to pH variation, as will be approached in this paper. Thus, chitosan/polyvinylpyrrolidone hydrogels of three different ratios between these two polymers (1:1, 7:3 and 3:7) were synthesized and putted in aqueous solution with different pHs. The pH was adjusted adding drops of NaOH and HCl, slowly. After the collection of results and in order to understand the phenomena in a visual way, models of the molecules were also elaborated using the Avogadro software. Therefore, it was possible to realize that the greater the ratio of chitosan in the hydrogel, the greater its sensitivity to pH. Such characteristic is associated with the amino (-NH2) groups in it structure, which are capable of protonating and deprotonating (depending of the pH), generating charges under the chemical structure of the material, which will expand its volume in order to minimize the repulsion between charges. In addition, it was also noted that the hydrogel expansion is inversely proportional to the pH increase. By practical tests, it was possible to conclude that chitosan/PVP hydrogel with ratio 7:3 is the most interesting once it presented a greater quantity of chitosan in its composition, what implied in more rigidity than the others and greater ease of handling, resulting in more reliable results. This hydrogel also showed higher sensitivity to pH.
文摘Objective: The ototoxicity of povidone-iodine has been documented in animal studies. However, there is limited evidence of these ototoxic effects in humans. This is the first report to show the ototoxic effects of povidoneiodine in a human subject.Patient: A 36-year-old woman came to our hospital complaining of left unilateral persistent hearing loss. One month before presentation, her child had accidentally struck her on her left ear. She applied approximately three drops of povidone-iodine(10% weight/volume) into her left auditory canal. Immediately after application, she felt severe pain and vertigo. An audiogram revealed severe left unilateral sensorineural hearing loss. Magnetic resonance imaging showed mild enhancement of the left vestibule and basal turn of the left cochlea.Conclusions: Even a single application of povidone-iodine could cause significant hearing loss and disequilibrium. It should, therefore, be used with caution.
文摘AIM: To evaluate the clinical characteristics of adenoviral keratoconjunctivitis, the management modalities, as well as the incidence of subepithelial corneal infiltrates(SEI).METHODS: Patients with characteristic clinical symptoms and signs, who presented to our clinic within the first week of symptoms and received the diagnosis of adenoviral keratoconjunctivitis between January 2013 and April 2016, were included in the study. A total of 211 patients were included in the study. Patients were evaluated for the incidence of clinical signs, late complications, management preferences, and the effect of diluted povidone-iodine(d-PVP-I) 2%. RESULTS: Patients’ mean age was 33.03±14.76 y. We observed an increase in the number of cases according to the years. At presentation and/or early follow-up, the clinical signs were conjunctival hyperemia(100%), conjunctival follicules(79.1%), edema of the eyelids(39.3%), chemosis(16.1%), pseudomembrane formation(16.6%), and corneal epitheliopathy(29.9%). During late follow-up 13.3% patients developed conjunctival subepithelial fibrosis, and 39.8% developed SEI. A significant decrease in the incidence of SEI development was observed in patients who used d-PVP-I 2%(P=0.032;33.3% vs 45.9%, respectively in patients who received d-PVP-I 2% and who did not).CONCLUSION: Adenoviral keratoconjunctivitis has a tremendous effect on patient’s comfort and abilities in short-term. Additionally, almost half of the patients develop visual problems related to SEI. According to our clinical experience, using d-PVP-I 2% in the first days of adenoviral keratoconjunctivitis might be helpful in reducing the risk of SEI as a complication.
基金This work was financially supported by the Higher Education Commission (HEC), Pakistan in the form of an HEC researchproject.
文摘Interactions of polyvinylpyrrolidone (PVP) with metal chlorides (MgCl 2 , CaCl 2 , KCl and BaCl 2 ) have been investigated by viscometric and spectrophotometric techniques in aqueous solutions. Intrinsic viscosity [η] of (PVP) has shown a discontinuity with varying concentration of metal chlorides. The decreasing order of effectiveness of cation is K 1+ > Ca 2+ > Mg 2+ > Ba 2+ for poly(vinylpyrrolidone) solution. Changes in the absorption spectra of the cosolutes were observed in the presence of PVP in the lower limit of the UV-visible region i.e. 200-210 nm. These changes were attributed to interaction of PVP molecules with the cosolute molecules. As the concentration of the cosolute increased, a red shift in the peaks was observed, indicating an increase in interaction between PVP and cosolutes.
文摘Background: Surgical site infection (SSI) is a dreaded nightmare for the Orthopaedic surgeon. Preoperative skin cleaning with antiseptics has been shown to reduce the microbial burden of the skin and results in reduced incidence of SSI. However, the ideal skin cleaning agent remains to be established. Aim: To compare the efficacy of Povidone-Iodine/Povidone-Iodine (PI-PI) combination with that of Chlorhexidine-Gluconate/Alcohol (CG-A) combination in re-ducing SSI in Orthopaedic surgeries. Methods: This was a prospective, randomized, double-blinded, controlled study. Subjects that met the selection criteria and gave consent were randomized into PI-PI group (test group) and the CG-A group (control group). Both the patients and the assessors for SSI were blinded to the group a participant belongs. Blocking was done on the type of surgery to cancel the confounding effect of surgery type on SSI. Standard perioperative protocols were applied to both groups. Assessment for features of SSI was done on the 3rd day, 7th day, 14th day, 6th week and 12th-week postoperative period. The diagnosis of SSI was made based on the Centers for Disease and Control (CDC) guidelines. Results: We recruited 124 patients for this study, 62 males and 54 females. The mean age of the subjects was 37.5 years (SD = 14.7 years). Sixty-two subjects were randomized into each group. There was no significant difference in the distribution of the genders in the study arms. Other possible confounders such as duration of hospital stay, use of drains, the surgeon involved and age were evenly distributed in the two groups. Eight patients did not complete the study. The overall incidence of SSI in the study was 2.6%. Subjects in the control group had an SSI of 3.4% while those in the PI-PI group had a rate of 1.8%;however, this was not significant, p = 0.579. Conclusion: Both CG-A and PI-PI combinations are equally efficacious as preoperative skin antiseptic in Orthopaedic implant surgeries.
文摘AIM:To investigate the effects of diquafosol sodium(DQS)for dry eye model induced with povidone-iodine(PI)solution.METHODS:Ten Sprague Dawley rats as the control group.Thirty Sprague Dawley rats were used to establish the dry eye model with stimulation of 10 g/L PI for 14d,then divided rats into three groups:dry eye group with no treatment(DED group,n=10);phosphate buffer saline treated group(PBS group,n=10);diquafosol treated group(DQS group,n=10).Clinical changes were observed by tear production test,fluorescein staining,tear breakup time(TBUT)test,corneal confocal microscope and ocular surface comprehensive analyzer.Eyeballs were collected on day 10 of treatment for hematoxylin-eosin(HE),periodic acid-Schiff(PAS),and alcian blue staining.TUNEL assay,polymorphonuclear(PMN)and mucin 1(MUC1)immunofluorescence were performed and corneal ultrastructural changes were detected by electron microscopy.RESULTS:Compared with DED and PBS groups,tear production(7.26±0.440 vs 4.07±0.474 mm;7.26±0.440 vs 3.74±0.280 mm;all P<0.01)and TBUT(7.37±0.383s vs 1.49±0.260s;7.37±0.383s vs 1.42±0.437s;all P<0.01)were significantly increased in DQS group.HE,PAS,and alcian blue staining and MUC1 immunofluorescence showed mucins and conjunctival goblet cells density(8.45±0.718 vs 5.21±0.813 cells/0.1 mm^(2);8.45±0.718 vs 5.36±0.615 cells/0.1 mm^(2);all P<0.01)increased in DQS group.Confocal microscopy,PMN immunofluorescence and TUNEL staining showed inflammatory infiltration and corneal epithelial cells apoptosis decreased in DQS group.The increased number of microvilli in corneal epithelial and the recovered cell junction were observed in DQS group.CONCLUSION:PI instillation can induce goblet cells and mucin loss,epithelial cell apoptosis and inflammation,which are consistent with the pathological manifestations of dry eye.Diquafosol can repair the ocular surface damage caused by PI,reduce corneal inflammation,inhibit corneal epithelial cell apoptosis,promote mucin secretion and maintain tear film stability.
基金supported financially by the National Natural Science Foundation of China(Grant No.51272107 and Grant No.51572126)the Department of Education of Jiangsu Province(KYLX_0352)Fundamental Research Funds for the Central Universities(No.30920140132038)
文摘In this paper, ultrafine nitrogen-doped TiO2 photocatalyst with enhanced photocatalytic water-splitting properties was successfully fabricated via a solvothermal method. Herein, polyvinylpyrrolidone(PVP) was used as both nitrogen source and stabilizer. The enhancement in water-splitting process can be attributed to the doping of element nitrogen, which could supply an intermediate energy level and promote the separation of photo-excited holes and electrons. Moreover, this paper provides a new application of high-molecular polymer to synthesize solar-driven water-splitting photocatalysts.
文摘Surgical Site Infections (SSIs) remain a prevalent issue in healthcare. An average of 2% to 4% of all Total Knee Arthroplasties (TKA/TKR) result in a Prosthetic Joint Infection (PJI) (Ashraf et al. , 2018). These surgical site infections cause significant distress to the patient and require extended courses of antibiotic treatment and revision surgery of the infected joint. SSIs also reduce financial reimbursement to the surgery facility and affect the performing surgeon’s performance scores. To prevent surgical infection, healthcare facilities have implemented various screening or decolonization methods to prevent surgical infection to may cause infection. Various treatment methods exist for managing MRSA preoperatively which include Povidone Iodine (PI) application as a universal decolonization method and/or screening every patient pre-operatively for MRSA and treating MRSA-positive patients with Mupirocin ointment. Both interventions are well-established in the literature. At the author’s facility, the elective TKR populations were analyzed while each intervention was implemented. In 2019 TKR patients underwent MRSA swabbing and testing and in 2021 PI decolonization was the decolonization method of choice. The study revealed that MRSA testing and swabbing were better at reducing SSI related to MRSA than Povidone Iodine decolonization.
文摘Doxorubicin-loaded nanoparticles, using doxorubicin (ADM) as model drug and vinylpyrrolidone as matrix, were prepared by inverse emulsion polymerization in the paper. The nanoparticles were characterized by telescope electron microscopy (TEM), laser light scattering technique (LLS) and infrared spectrum (IR). LLS test showed that the optimal prepared ADM-loaded nanoparticles had an average size 18.8nm and a narrow size distribution between 15nm and 32nm, which was consistent with the result obtained by TEM. And 1R results indicated that the nanoparticles consisted of ADM and polyvinylpyrrolidone (PVP).
文摘Background: Povidone-iodine (PVI) irrigation is currently used to decrease the frequency of postoperative surgical site infections. Ethanol (EtOH) is sometimes applied to prevent local recurrence after curettage of benign bone tumors. However, the effects of PVI and EtOH on surrounding soft tissue and on bone union are unclear. The purpose of this study was to determine whether PVI or EtOH adversely affects the cancellous bone healing of the osteotomy site at the proximal tibia in rats. Methods: A cancellous bone osteotomy was performed at the right proximal tibia in 4-month-old, female, Sprague Dawley rats. Vehicle, 10% PVI, or 95% EtOH-soaked gauze was inserted into the osteotomy site and maintained for 6 minutes. The rats were euthanized 2 or 4 weeks after the osteotomy. Results: Two weeks after treatment, the bone union rate was significantly higher in the vehicle group than in the PVI group and the EtOH group (p < 0.001). However, the bone union rate was not significantly different between the PVI and EtOH groups. There was no significant difference among the three groups in the bone union rate 4 weeks after treatment. Conclusion: PVI or EtOH delayed bone union of the cancellous bone osteotomy site of the proximal tibia in the early phase (2 weeks), but not at 4 weeks, in rats.