Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.536
Filtrar
1.
Mikrochim Acta ; 191(5): 262, 2024 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613581

RESUMO

Rapid and sensitive detection of carcinoembryonic antigen (CEA) is of great significance for cancer patients. Here, molybdenum (Mo) was doped into bismuth oxide (Bi2O3) by one-pot hydrothermal method forming porous tremella Bi2MoO6 nanocomposites with a larger specific surface area than the spherical structure. Then, a new kind of hydrangea-like TiO2/Bi2MoO6 porous nanoflowers (NFs) was prepared by doping titanium into Bi2MoO6, where titanium dioxide (TiO2) grew in situ on the surface of Bi2MoO6 nanoparticles (NPs). The hydrangea-like structure provides larger specific surface area, higher electron transfer ability and biocompatibility as well as more active sites conducive to the attachment of anti-carcinoembryonic antigen (anti-CEA) to TiO2/Bi2MoO6 NFs. A novel label-free electrochemical immunosensor was then constructed for the quantitative detection of CEA using TiO2/Bi2MoO6 NFs as sensing platform, showing a good linear relationship with CEA in the concentration range 1.0 pg/mL ~ 1.0 mg/mL and a detection limit of 0.125 pg/mL (S/N = 3). The results achieved with the designed immunosensor are comparable with many existing immunosensors used for the detection of CEA in real samples.


Assuntos
Técnicas Biossensoriais , Bismuto , Hydrangea , Molibdênio , Humanos , Biomarcadores Tumorais , Antígeno Carcinoembrionário , Porosidade , Imunoensaio
2.
Helicobacter ; 29(2): e13073, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601987

RESUMO

BACKGROUND: Helicobacter pylori infection and its associated diseases represent a significant global health concern. Patients who cannot use amoxicillin pose a therapeutic challenge and necessitate alternative medications. Preliminary research indicates that cefuroxime demonstrates promising potential for eradicating H. pylori infection, and there is a lack of comprehensive review articles on the use of cefuroxime. MATERIALS AND METHODS: This study conducts a thorough systematic literature review and synthesis. A comprehensive systematic search was conducted in PubMed, Web of Science, EMBASE, China National Knowledge Infrastructure, China Biology Medicine disc, and Wanfang Data up to January 13, 2024. The search strategy utilized the following keywords: (Cefuroxime) AND (Helicobacter pylori OR Helicobacter nemestrinae OR Campylobacter pylori OR Campylobacter pylori subsp. pylori OR Campylobacter pyloridis OR H. pylori OR Hp) for both English and Chinese language publications. Sixteen studies from five different countries or regions were included in final literature review. RESULTS: Analysis results indicate that H. pylori is sensitive to cefuroxime, with resistance rates similar to amoxicillin being relatively low. Regimens containing cefuroxime have shown favorable eradication rates, which were comparable to those of the regimens containing amoxicillin. Regarding safety, the incidence of adverse reactions in cefuroxime-containing eradication regimens was comparable to that of amoxicillin-containing regimens or other bismuth quadruple regimens, with no significant increase in allergic reactions in penicillin-allergic patients. Regarding compliance, studies consistently report high compliance rates for regimens containing cefuroxime. CONCLUSION: Cefuroxime can serve as an alternative to amoxicillin for the patients allergic to penicillin with satisfactory efficacies, safety, and compliance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/tratamento farmacológico , Cefuroxima/uso terapêutico , Antibacterianos/efeitos adversos , Quimioterapia Combinada , Amoxicilina/uso terapêutico , Bismuto/efeitos adversos , Penicilinas/uso terapêutico , Resultado do Tratamento , Inibidores da Bomba de Prótons/uso terapêutico
3.
Sci Rep ; 14(1): 8986, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637591

RESUMO

Potassium-competitive acid blockers (P-CABs) provide potent acid inhibition, yet studies on P-CAB-based quadruple therapy for H. pylori eradication are limited. We theorized that integrating bismuth subsalicylate into a quadruple therapy regimen could enhance eradication rates. However, data on the efficacy of vonoprazan bismuth quadruple therapy are notably scarce. Therefore, the aim of this study was to evaluate the efficacy of vonoprazan-based bismuth quadruple therapy in areas with high clarithromycin and levofloxacin resistance. This was a prospective, single-center, randomized trial conducted to compare the efficacy of 7-day and 14-day vonoprazan-based bismuth quadruple therapy for H. pylori eradication between June 1, 2021, and March 31, 2022. Qualified patients were randomly assigned to the 7-day or 14-day regimen (1:1 ratio by computer-generated randomized list as follows: 51 patients for the 7-day regimen and 50 patients for the 14-day regimen). The regimens consisted of vonoprazan (20 mg) twice daily, bismuth subsalicylate (1024 mg) twice daily, metronidazole (400 mg) three times daily, and tetracycline (500 mg) four times daily. CYP3A4/5 genotyping and antibiotic susceptibility tests were also performed. Successful eradication was defined as 13negative C-UBTs 4 weeks after treatment. The primary endpoint was to compare the efficacy of 7-day and 14-day regimens as first-line treatments, which were assessed by intention-to-treat (ITT) and per-protocol (PP) analyses. The secondary endpoints included adverse effects. A total of 337 dyspeptic patients who underwent gastroscopy were included; 105 patients (31.1%) were diagnosed with H. pylori infection, and 101 patients were randomly assigned to each regimen. No dropouts were detected. The antibiotic resistance rate was 33.3% for clarithromycin, 29.4% for metronidazole, and 27.7% for levofloxacin. The CYP3A4 genotype was associated with 100% rapid metabolism. The H. pylori eradication rates for the 7-day and 14-day regimens were 84.4%, 95% CI 74.3-94.2 and 94%, 95% CI 87.4-100, respectively (RR difference 0.25, 95% CI 0.03-0.53, p value = 0.11). Interestingly, the 14-day regimen led to 100% eradication in the clarithromycin-resistant group. Among the patients in the 7-day regimen group, only two exhibited resistance to clarithromycin; unfortunately, neither of them achieved a cure from H. pylori infection. The incidence of adverse events was similar in both treatment groups, occurring in 29.4% (15/51) and 28% (14/50) of patients in the 7-day and 14-day regimens, respectively. No serious adverse reactions were reported. In conclusion, 14 days of vonoprazan-based bismuth quadruple therapy is highly effective for H. pylori eradication in areas with high levels of dual clarithromycin and levofloxacin resistance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Compostos Organometálicos , Pirróis , Salicilatos , Sulfonamidas , Humanos , Claritromicina/farmacologia , Bismuto/uso terapêutico , Bismuto/efeitos adversos , Levofloxacino/efeitos adversos , Metronidazol/efeitos adversos , Estudos Prospectivos , Citocromo P-450 CYP3A , Antibacterianos/efeitos adversos , Infecções por Helicobacter/genética , Quimioterapia Combinada , Resultado do Tratamento
4.
BMC Gastroenterol ; 24(1): 131, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609893

RESUMO

OBJECTIVE: To compare the potential efficacy and safety of dual therapy and quadruple therapy with vonoprazan (VPZ) as well as the standard quadruple therapy of proton pump inhibitor (PPI) for the eradication of Helicobacter pylori (Hp) infection in Hainan province. METHODS: A single-centre, non-blinded, non-inferiority randomized controlled trial was conducted at the outpatient department of gastroenterology at the Second Affiliated Hospital of Hainan Medical University from June 2022 to February 2023. 135 patients aged 18-75 years with Hp infection were enrolled and randomized into three different groups (group V1: VPZ 20 mg twice a day and amoxicillin 1.0 g three times a day for 14 days V2: vonoprazan 20 mg, amoxicillin capsules 1.0 g, furazolidone 0.1 g and bismuth potassiulm citrate 240 mg, twice daily for 14 days;; group V3: ilaprazole 5 mg, Amoxicillin 1.0 g, Furazolidone 100 mg, bismuth potassiulm citrate 240 mg, twice a day for 14 days). Four weeks after the end of treatment, Hp eradication was confirmed by rechecking 13C-urea breath test (UBT). RESULTS: The eradication efficacy of V1 and V3 was non-inferior to that of V2, which is consistent with the results obtained from the Kruskal-Wallis H test. The eradication rate by intentional analysis was 84.4% (38/45, 95%CI 73.4%-95.5%, P>0.05) for all the three groups. If analyzed by per-protocol, the eradication rates were 88.4% (38/43, 95%CI 78.4%-98.4%), 92.7% (38/41, 95%CI 84.4%-101.0%),88.4% (38/43,95%CI 78.4%-98.4%) in groups V1, V2 and V3, respectively, which did not show a significant difference (P > 0.05). The incidence of adverse effects was significantly lower in VPZ dual therapy compared to the other two treatment regimens (P < 0.05). VPZ dual therapy or quadruple therapy was also relatively less costly than standard quadruple therapy. CONCLUSION: VPZ dual therapy and quadruple therapy shows promise of not being worse than the standard quadruple therapy by a clinically relevant margin. More studies might be needed to definitively determine if the new therapy is equally effective or even superior.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Pirróis , Sulfonamidas , Humanos , Infecções por Helicobacter/tratamento farmacológico , Bismuto/uso terapêutico , Furazolidona/uso terapêutico , Amoxicilina/uso terapêutico , Citratos
5.
Nano Lett ; 24(15): 4562-4570, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591327

RESUMO

Heteroions doped Ag2S nanocrystals (NCs) exhibiting enhanced near-infrared-II emission (NIR-II) hold great promise for glioma diagnosis. Nevertheless, current doped Ag2S NCs paradoxically improved properties via toxic dopants, and the blood-brain barrier (BBB) constitutes another challenge for orthotopic glioma imaging. Thus, it is urgent to develop biofriendly high-bright Ag2S NCs with active BBB-penetration for glioma-targeted imaging. Herein, bismuth (Bi) was screened to obtain Bi-Ag2S NCs with high absolute PLQY (∼13.3%) for its matched ionic-radius (1.03 Å) with Ag+. The Bi-Ag2S NCs exhibited a higher luminance and deeper penetration (5-6 mm) than clinical indocyanine green. Upon conjugation with lactoferrin, the NCs acquired BBB-crossing and glioma-targeting abilities. Time-dependent NIR-II-imaging demonstrated their effective accumulation in glioma with skull/scalp intact after intravenous injection. Moreover, the toxic-metal-free NCs exhibited negligible toxicity and great biocompatibility. The success of leveraging the ion-radii comparison may unlock the full potential of doped-Ag2S NCs in bioimaging and inspire the development of various doped NIR-II NCs.


Assuntos
Glioma , Nanopartículas Metálicas , Humanos , Bismuto , Rádio (Anatomia) , Nanopartículas Metálicas/química , Crânio , Glioma/diagnóstico por imagem
6.
Helicobacter ; 29(2): e13059, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38443329

RESUMO

BACKGROUND: Vonoprazan, a novel acid suppressant, has recently emerged as a regimen for eradicating Helicobacter pylori. However, uncertainties exist about the effectiveness and safety of VPZ-based regimens compared with those of bismuth-based quadruple therapy in eradicating H. pylori. The present meta-analysis was performed to compare the effectiveness and safety of vonoprazan-based regimens with those of bismuth quadruple therapy in eradicating H. pylori. MATERIALS AND METHODS: All randomized controlled trials and non-randomized controlled trials comparing the vonoprazan-based therapy with the bismuth quadruple therapy were included in this meta-analysis. Information was also extracted by two evaluators, and if heterogeneity existed, a random-effects model was used to calculate the combined relative ratio and 95% confidence interval; otherwise, a fixed-effects model was used. And subgroup analyses were performed to explore the sources of heterogeneity. RESULTS: A total of 10 studies, comprising 2587 patients were included in the meta-analysis. The results showed that the combined eradication rate of patients treated with the vonoprazan-based regimen was significantly higher than that of patients treated with bismuth quadruple therapy, in both intention-to-treat and per-protocol analyses, and the differences were statistically significant. Among the intention-to-treat analyses results: (90.28% vs. 83.64% [odds ratio (OR) = 1.85, 95% confidence interval (CI) (1.27, 2.70), p = 0.001]); in the per-protocol analyses: (94.80% vs. 89.88%, [OR = 2.25, 95% CI (1.37, 3.69), p = 0.001]). The occurrence of adverse events was significantly lower in patients treated with vonoprazan-based regimens than in those treated with bismuth quadruple therapy, (14.50% vs. 25.89%, [OR = 0.49, 95% CI (0.32, 0.75), p = 0.001]). CONCLUSIONS: For eradicating H. pylori, vonoprazan-based regimens are remarkably advantageous over bismuth quadruple therapy. Furthermore, vonoprazan-based regimens exhibit a lower rate of adverse events than bismuth quadruple therapy.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Sulfonamidas , Humanos , Bismuto/efeitos adversos , Infecções por Helicobacter/tratamento farmacológico , Pirróis/efeitos adversos
7.
J Appl Biomater Funct Mater ; 22: 22808000241236590, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444166

RESUMO

OBJECTIVE: To evaluate the antitumor and antimicrobial properties of an alginate-based membrane (ABM) loaded with bismuth lipophilic nanoparticles (BisBAL NPs) and cetylpyridinium chloride (CPC) on clinically isolated bacteria and a pancreatic cancer cell line. MATERIAL AND METHODS: The BisBAL NP-CPC ABM was characterized using optical and scanning electron microscopy (SEM). The antimicrobial potential was measured using the disk-diffusion assay, and antibiofilm activity was determined through the live/dead assay and fluorescence microscopy. The antitumor activity was analyzed on the pancreatic cell line (Panc 03.27) using the MTT assay and live/dead assay with fluorescence microscopy. RESULTS: After a 24-h exposure (37°C, aerobic conditions), 5 µM BisBAL NP reduced the growth of K. pneumoniae by 77.9%, while 2.5 µM BisBAL NP inhibited the growth of Salmonella, E. faecalis and E. faecium by 82.9%, 82.6%, and 78%, respectively (p < 0.0001). The BisBAL NPs-CPC ABM (at a ratio of 10:1; 500 and 50 µM, respectively) inhibited the growth of all isolated bacteria, producing inhibition halos of 9.5, 11.2, 7, and 10.3 mm for K. pneumoniae, Salmonella, E. faecalis, and E. faecium, respectively, in contrast to the 6.5, 9.5, 8.5, and 9.8 mm obtained with 100 µM ceftriaxone (p < 0.0001). The BisBAL NPs-CPC ABM also reduced bacterial biofilms, with 81.4%, 74.5%, 97.1%, and 79.5% inhibition for K. pneumoniae, E. faecium, E. faecalis, and Salmonella, respectively. Furthermore, the BisBAL NPs-CPC ABM decreased Panc 03.27 cell growth by 76%, compared to 18% for drug-free ABM. GEM-ABM reduced tumoral growth by 73%. The live/dead assay confirmed that BisBAL NPs-CPC-ABM and GEM-ABM were cytotoxic for the turmoral Panc 03.27 cells. CONCLUSION: An alginate-based membrane loaded with BisBAL NP and CPC exhibits dual antimicrobial and antitumoral efficacy. Therefore, it could be applied in cancer treatment and to diminish the occurrence of surgical site infections.


Assuntos
Anti-Infecciosos , Bismuto , Dimercaprol/análogos & derivados , Compostos Organometálicos , Cetilpiridínio/farmacologia , Anti-Infecciosos/farmacologia , Alginatos/farmacologia , Klebsiella pneumoniae
8.
Medicine (Baltimore) ; 103(10): e37476, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457567

RESUMO

Vonoprazan, a novel acid suppressant and the first potassium-competitive acid blocker, has the potential to enhance the eradication rate of Helicobacter pylori due to its robust acid-suppressing capacity. This study aimed to compare the efficacy of vonoprazan-based dual therapy (vonoprazan-amoxicillin, VA) with vonoprazan-based bismuth quadruple therapy (VBQT) as a first-line treatment for H pylori infection. This retrospective single-center non-inferiority study was conducted in China. Treatment-naive H pylori-positive patients aged 18 to 80 received one of the 2 treatment regimens at our center. The VA group received vonoprazan 20 mg twice daily and amoxicillin 1000 mg 3 times daily for 14 days, whereas the VBQT group received vonoprazan 20 mg, amoxicillin 1000 mg, clarithromycin 500 mg, and bismuth potassium citrate 220 mg twice daily for 14 days. The eradication rate was evaluated 4 to 6 weeks after treatment using the carbon-13/14 urea breath test. Propensity score matching was used to analyze eradication rates, adverse events (AEs), and patient compliance between the 2 groups. Initially, 501 patients were included, and after propensity score analysis, 156 patients were selected for the study. Intention-to-treat analysis showed eradication rates of 87.2% (95% CI, 79.8-94.6%) for the VA group and 79.5% (95% CI, 70.5-88.4%) for the VBQT group (P = .195). Per-protocol analysis demonstrated rates of 94.4% (95% CI, 89.2-99.7%) for the VA group and 96.8% (95% CI, 92.4-100%) for the VBQT group (P = .507). Non-inferiority was confirmed between the 2 groups, with P values < .025. The VA group showed a lower rate of AEs (10.3% vs 17.9%, P = .250) compared to the VBQT group. There were no significant differences in patient compliance between the 2 groups. In treatment-naive patients with H pylori infection, both the 14-day VA and VBQT regimens demonstrated comparable efficacy, with excellent eradication rates. Moreover, due to reduced antibiotic usage, lower rate of AEs, and lower costs, VA dual therapy should be prioritized.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Pirróis , Sulfonamidas , Humanos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/etiologia , Bismuto/uso terapêutico , Estudos Retrospectivos , Pontuação de Propensão , Inibidores da Bomba de Prótons/efeitos adversos , Quimioterapia Combinada , Antibacterianos , Amoxicilina/uso terapêutico , Claritromicina/uso terapêutico , Resultado do Tratamento
9.
Int J Biol Macromol ; 264(Pt 1): 130533, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428782

RESUMO

In this work, silver­bismuth oxide encapsulated 1,3,5-triazine-bis(4-methylbenzenesulfonyl)-hydrazone functionalized chitosan (SBO/FCS) nanocomposite was synthesized by a simple hydrothermal method. The amine (-NH2) group was functionalized by the addition of cyanuric acid chloride followed by 4-methylbenzenesulfonol hydrazide. The SBO/FCS has been characterized by FT-IR, X-ray diffraction, XPS, HR-SEM, HR-TEM, AFM, and thermogravimetry (TGA). Under the optimum conditions, the SBO/FCS sensor showed brilliant electrochemical accomplishment for the sensing of glucose and H2O2 by a limit of detection (LOD) of 0.057 µM and 0.006 µM. It also showed linearity for glucose 0.008-4.848 mM and for H2O2 of 0.01-6.848 mM. Similarly, the sensor exhibited a low sensitivity to glucose (32 µA mM-1 cm-2) and a good sensitivity to H2O2 (295 µA mM-1 cm-2). In addition, that the prepared electrode could be used to sense the glucose and H2O2 levels in real samples such as blood serum and HeLa cell lines. The screen printed electrode (SPE) immunosensor could sense the E. coli O157:H7 concurrently and quantitatively with a linear range of 1.0 × 101-1.0 × 109 CFU mL-1 and a LOD of 4 CFU mL-1. Likewise, the immunosensor efficiently detect spiked E. coli O157:H7 in milk, chicken, and pork samples, with recoveries ranging from 89.70 to 104.72 %, demonstrating that the immunosensor was accurate and reliable.


Assuntos
Técnicas Biossensoriais , Bismuto , Quitosana , Escherichia coli O157 , Nanocompostos , Humanos , Peróxido de Hidrogênio/química , Prata , Glucose , Técnicas Biossensoriais/métodos , Hidrazonas , Espectroscopia de Infravermelho com Transformada de Fourier , Células HeLa , Imunoensaio/métodos , Nanocompostos/química
10.
Chemosphere ; 355: 141744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522669

RESUMO

Pesticides pollute natural water reservoirs through persistent accumulation. Therefore, their toxicity and degradability are serious issues. Carbendazim (CBZ) is a pesticide used against fungal infections in agricultural crops, and its overexploitation detrimentally affects aquatic ecosystems and organisms. It is necessary to design a logical, efficient, and field-deployable method for monitoring the amount of CBZ in environmental samples. Herein, a nano-engineered bismuth selenide (Bi2Se3)/functionalized carbon nanofiber (f-CNF) nanocomposite was utilized as an electrocatalyst to fabricate an electrochemical sensing platform for CBZ. Bi2Se3/f-CNF exhibited a substantial electroactive surface area, high electrocatalytic activity, and high conductivity owing to the synergistic interaction of Bi2Se3 with f-CNF. The structural chemical compositions and morphology of the Bi2Se3/f-CNF nanocomposite were confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FESEM). Electrochemical analysis was carried out using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). The voltammetry and impedance experiments exposed that the Bi2Se3/f-CNF-modified GCE has attained adequate electrocatalytic function with amended features of electron transportation (Rct = 35.93 Ω) and improved reaction sites (0.082 cm2) accessible by CBZ moiety along with exemplary electrochemical stability (98.92%). The Bi2Se3/f-CNF nanocomposite exhibited higher sensitivity of 0.2974 µA µM-1cm-2 and a remarkably low limit of detection (LOD) of 1.04 nM at a broad linera range 0.001-100 µM. The practicability of the nanocomposite was tested in environmental (tap and pond water) samples, which supports excellent signal amplification with satisfactory recoveries. Hence, the Bi2Se3/f-CNF nanocomposite is a promising electrode modifier for detecting CBZ.


Assuntos
Benzimidazóis , Bismuto , Carbamatos , Carbono , Nanofibras , Compostos de Selênio , Carbono/química , Nanofibras/química , Ecossistema , Água , Técnicas Eletroquímicas/métodos , Eletrodos
11.
J Mol Graph Model ; 129: 108729, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38479238

RESUMO

The recent discovery of superconductivity behavior in the mother BiS2-layered compounds has captivated the attention of several physicists. The crystal structure of superconductors with alternate layers of BiS2 is homologous to that of cuprates and Fe-based superconductors. The full-potential linearized augmented plane-wave (FP-LAPW) technique was utilized to investigate the electronic structures and density of states in the vicinity of the Fermi energy of SrFBiS2 and BaFBiS2 compounds under the electron carriers doping. The introduction of electron doping (carries doping) reveals that the host compounds SrFBiS2 and BaFBiS2 exhibit features indicative of superconductivity. This carrier doping of SrFBiS2 and BaFBiS2 compounds (electron-doped) has a significant impact on the lowest conduction states near the Fermi level for the emergence of the superconducting aspect. The electron doping modifies and induces changes in the electronic structures with superconducting behavior in (Ae)1.7FBiS2(Ae=Sr,Ba) compounds. A Fermi surface nesting occurred under the modification of electrons (carriers) doping in the host compounds SrFBiS2 and BaFBiS2. Furthermore, the optical characteristics of the carrier-doped SrFBiS2 and BaFBiS2 compounds are simulated. Due to the anisotropic behavior, the optical properties of these materials based on BiS2 demonstrate a pronounced polarization dependency. The starting point at zero photon energy in the infrared region is elucidated by considering the Drude features in the optical conductivity spectra of SrFBiS2 and BaFBiS2 compounds, when the electron carriers doping is applied. It was clearly noticed that the spin-orbit coupling (SOC) influences the electronic band structures, density of states, Femi surface, and optical features because of the heavy Bismuth atom, which may disclose fascinating aspects. Further, we conducted simulations to assess the thermoelectric properties of these mother compounds. The two BiS2-layered compounds could be suitable for practical thermoelectric purposes and are highlighted through assessment of electrical conductivity, thermal conductivity, Seebeck coefficient, and power factor. As a result, we propose that the mechanisms of superconducting behavior in BiS2 family may pave new avenues for investigating the field of unconventional superconductivity. It may also provide new insights into the origin of high-Tc superconductivity nature.


Assuntos
Bismuto , Eletrônica , Condutividade Elétrica , Anisotropia , Elétrons
12.
Int J Biol Macromol ; 265(Pt 1): 130797, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479662

RESUMO

In recent years, photocatalytic technology has been introduced to develop a new kind antimicrobial agents fighting antibiotic abusing and related drug resistance. The efforts have focused on non-precious metal photocatalysts along with green additives. In the present work, a novel bis-S heterojunctions based on the coupling of polysaccharide (CS) and bismuth-based MOF (CAU-17) s synthesized through a two-step method involving amidation reaction under mild conditions. The as prepared photocatalyst literally extended the light response to the near-infrared region. Owing to its double S-type heterostructure, the lifetime of the photocarriers is significantly prolonged and the redox capacity are enhanced. As a result, the as prepared photocatalyst indicated inhibition up to 99.9 % under 20 min of light exposure against Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria as well as drug-resistant bacteria (MRSA). The outstanding photocatalytic performance is attributed to the effective charge separation and migration due to the unique double S heterostructure. Such a double S heterostructure was confirmed through transient photocurrent response, electrochemical impedance spectroscopy tests and electron spin resonance measurements. The present work provides a basis for the simple synthesis of high-performance heterojunction photocatalytic inhibitors, which extends the application of CAU-17 in environmental disinfection and wastewater purification.


Assuntos
Quitosana , Estruturas Metalorgânicas , Bismuto/química , Escherichia coli , Quitosana/farmacologia , Estruturas Metalorgânicas/farmacologia , Staphylococcus aureus , Catálise
13.
Med J Malaysia ; 79(Suppl 1): 8-13, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38555879

RESUMO

INTRODUCTION: Bismuth oxide (Bi2O3) particles gained attention in preclinical research especially in medical imaging. Bismuth oxide with its long circulation time is an alternative to the current iodine contrast media which directly possesses high X-ray attenuation coefficient. Exploration of bismuth compound is hampered owing to challenges in synthesizing control for in vivo stability. MATERIALS AND METHODS: This study aimed are to characterize Bi2O3 particles synthesized at 60, 90 and 120 °C via hydrothermal method and investigated cytotoxicity of cell viability assay, cell morphology analysis, intracellular reactive oxygen species (ROS) assay and expression of ER stress genes by real-time PCR. RESULTS: Results indicated that the size of rod-shaped Bi2O3 particles increased with rising synthesizing temperatures. The cytotoxicity of Bi2O3 particles in Chang liver cells was size-dependent. Bigger-sized Bi2O3 particles resulted in lesser toxicity effects. mRNA expressions of GRP78 and C/EBP homologous protein (CHOP) were down-regulated in all treated Chang liver cells due to the increasing size of Bi2O3 particles. Bi2O3 particles synthesized at 120 °C was found to be less toxic than iodine. CONCLUSION: Data suggested that the response of Chang liver cells to Bi2O3 particle cytotoxicity has a significant relationship with its reaction temperatures. This outcome is important in hazard assessment of Bi2O3 particles as a new contrast media and provides better understanding in synthesizing control to enhance its biocompatibility.


Assuntos
Bismuto , Iodo , Humanos , Bismuto/toxicidade , Meios de Contraste/toxicidade , Temperatura
14.
Bull Exp Biol Med ; 176(4): 501-504, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491259

RESUMO

High X-ray absorption combined with photothermal properties make bismuth nanoparticles (Bi NP) a promising agent for multimodal cancer theranostics. However, the synthesis of Bi NP by the "classical" chemical methods has numerous limitations, including potential toxicity of the produced nanomaterials. Here we studied in vitro toxicity of laser-synthesized Bi NP coated with Pluronic F-127 on mouse fibroblast cell line L929. The survival of L929 cells decreased linearly with increasing the concentration of Bi NP in a concentration range of 3-500 µg/ml; the LC50 value was 57 µg/ml. The unique combination of functional properties and moderate toxicity of the laser-synthesized Bi NP makes them a new promising platform for sensitization of multimodal cancer theranostics.


Assuntos
Nanopartículas Metálicas , Animais , Camundongos , Bismuto/toxicidade , Bismuto/química , Linhagem Celular Tumoral , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Nanopartículas/toxicidade , Nanopartículas/química , Nanoestruturas , Neoplasias/metabolismo , Fototerapia/métodos
15.
Environ Sci Technol ; 58(13): 6049-6057, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38525996

RESUMO

High Cl- concentration in saline wastewater (e.g., landfill leachate) limits wastewater purification. Catalytic Cl- conversion into reactive chlorine species (RCS) arises as a sustainable strategy, making the salinity profitable for efficient wastewater treatment. Herein, aiming to reveal the structure-property relationship in Cl- utilization, bismuth oxychloride (BiOCl) photocatalysts with coexposed {001} and {110} facets are synthesized. With an increasing {001} ratio, the RCS production efficiency increases from 75.64 to 96.89 µg L-1 min-1. Mechanism investigation demonstrates the fast release of lattice Cl- as an RCS and the compensation of ambient Cl-. Correlation analysis between the internal electric field (IEF, parallel to [001]) and normalized efficiency on {110} (kRCS/S{110}, perpendicular to [001]) displays a coefficient of 0.86, validating that the promoted carrier dynamics eventually affects Cl- conversion on the open layered structure. The BiOCl photocatalyst is well behaved in ammonium (NH4+-N) degradation ranging from 20 to 800 mg N L-1 with different chlorinity (3-12 g L-1 NaCl). The sustainable Cl- conversion into RCS also realizes 85.4% of NH4+-N removal in the treatment of realistic landfill leachate (662 mg of N L-1 NH4+-N). The structure-property relationship provides insights into the design of efficient catalysts for environment remediation using ambient Cl-.


Assuntos
Compostos de Amônio , Bismuto , Poluentes Químicos da Água , Águas Residuárias , Poluentes Químicos da Água/química , Salinidade
16.
Langmuir ; 40(13): 7060-7066, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38513212

RESUMO

Nanosheet arrays with stable signal output have become promising photoactive materials for photoelectrochemical (PEC) immunosensors. However, an essential concern is the facile recombination of carriers in one-component nanoarrays, which cannot be readily prevented, ultimately resulting in weak photocurrent signals. In this study, an immunosensor using gold nanoparticle-anchored BiOI/Bi2S3 nanosheet arrays (BiOI/Bi2S3/Au) as a signal converter was fabricated for sensitive detection of cardiac troponin I (cTnI). The ternary nanosheet arrays were prepared by a simple method in which Bi2S3 was well-coated on the BiOI surface by in situ growth, whereas the addition of Au further improved the photoelectric conversion efficiency and could link more antibodies. The three-dimensional (3D) ordered sheet-like network array structure and BiOI/Bi2S3/Au ternary nanosheet arrays showed stable and high photoelectric signal output and no significant difference in signals across different batches under visible light excitation. The fabricated immunosensor has a sensitive response to the target detection marker cTnI in a wide linear range of 500 fg/mL to 50 ng/mL, and the detection limit was 32 fg/mL, demonstrating good stability and selectivity. This work not only shows the great application potential of ternary heterojunction arrays in the field of PEC immunosensors but also provides a useful exploration for improving the stability of immunosensors.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Troponina I , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Imunoensaio/métodos , Limite de Detecção , Troponina I/química , Troponina I/imunologia , Bismuto/química
17.
J Contemp Dent Pract ; 25(1): 35-40, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38514429

RESUMO

AIM: The aim of the present study was to evaluate the shear bond strength of resin-modified glass ionomer cement with two different types of mineral trioxide aggregate at different time intervals. MATERIALS AND METHODS: A total of 80 cylindrical blocks were prepared using a self-cure acrylic resin with a central cavity of 4 mm internal diameter and 2 mm height. The prepared samples were randomly divided into two groups (n = 40 each) according to the type of MTA cements used (ProRoot MTA and MTA Angelus). Two groups were further sub-divided into four sub-groups of 10 samples each according to the different time intervals. ProRoot MTA and MTA Angelus were placed in the prepared cavity and a wet cotton pellet was placed over the filled cavity. A hollow plastic tube was placed over the MTA surface and resin-modified glass ionomer cement (RMGIC) was placed into the hollow plastic tube and light-cured (Spectrum 800, Dentsply Caulk Milford, DE, USA) according to the time intervals decided. After light curing the plastic tubes were removed carefully and the specimens were stored at 37°C and 100% humidity for 24 hours to encourage setting of MTA. The specimens were mounted in a universal testing machine (ADMET) and a crosshead speed of 0.5 mm/min was applied to each specimen by using a knife-edge blade until the bond between the MTA and RMGIC failed. The data were statistically analyzed using ANOVA, post hoc Tukey's t-test and Fisher's t-test and p-value ≤ 0.5 was considered significant. RESULTS: For both ProRoot MTA and MTA Angelus there was no statistically significant difference between 45 minutes and 24 hours (p-value ≥ 0.8). For ProRoot MTA, shear bond strength value at 10 minutes were significantly lower than 45 minutes and 24 hours group. However, for MTA Angelus, shear bond strength value at 10 minute was not significantly different from 45 minutes group (p-value ≥ 0.3). For both ProRoot MTA and MTA Angelus shear bond strength value at 0 minute were the least and were significantly lower than 10 minutes, 45 minutes, and 24 hours, respectively (p-value ≥ 0.000). CONCLUSION: Resin-modified glass ionomer cement can be layered over MTA Angelus after it is allowed to set for 10 minutes. However, ProRoot MTA should be allowed to set for at least 45 minutes before the placement of RMGIC to achieve better shear bond strength. CLINICAL SIGNIFICANCE: Due to the variety of types of mineral trioxide aggregate cements available in dentistry, it is justifiable to emphasize on different time intervals as it may affect the shear bond strength of restorative cements. Such information is pivotal for the clinicians while using mineral aggregate-based cements that receive forces from the condensation of restorative materials or occlusion, as the compressive strength may be affected due to different time intervals. How to cite this article: Tyagi N, Chaman C, Anand S, et al. Comparative Evaluation of Shear Bond Strength of Resin-modified Glass Ionomer Cement with ProRoot MTA and MTA Angelus. J Contemp Dent Pract 2024;25(1):35-40.


Assuntos
Bismuto , Colagem Dentária , Óxidos , Materiais Restauradores do Canal Radicular , Silicatos , Cimentos de Ionômeros de Vidro/química , Resinas Compostas/química , Materiais Restauradores do Canal Radicular/química , Resistência ao Cisalhamento , Teste de Materiais
18.
Langmuir ; 40(12): 6515-6523, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466089

RESUMO

Photocatalysis represents an effective technology for environmental remediation. Herein, a series of Zn-doped BiOBr hollow microspheres are synthesized via one-pot solvothermal treatment of bismuth nitrate and dodecyl ammonium bromide in ethylene glycol along with a calculated amount of zinc acetate. Whereas the materials morphology and crystal structure remain virtually unchanged upon Zn-doping, the photocatalytic performance toward the degradation of ciprofloxacin is significantly improved under visible light irradiation. This is due to the formation of a unique band structure that facilitates the separation of photogenerated electron-hole pairs, reduced electron-transfer resistance, and enhanced electron mobility and carrier concentration. The best sample consists of a Zn doping amount of 1%, which leads to a 99.2% degradation rate of ciprofloxacin under visible photoirradiation for 30 min. The resulting photocatalysts also exhibit good stability and reusability, and the degradation intermediates exhibit reduced cytotoxicity compared to ciprofloxacin. These results highlight the unique potential of BiOBr-based photocatalysts for environmental remediation.


Assuntos
Antibacterianos , Zinco , Antibacterianos/farmacologia , Microesferas , Luz , Bismuto/química , Ciprofloxacina , Catálise
19.
Sci Rep ; 14(1): 5772, 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459204

RESUMO

Aluminum in its Al3+ form is a metal that inhibits plant growth, especially in acidic soils (pH < 5.5). Rapid and accurate quantitative detection of Al3+ in agricultural soils is critical for the timely implementation of remediation strategies. However, detecting metal ions requires time-consuming preparation of samples, using expensive instrumentation and non-portable spectroscopic techniques. As an alternative, electrochemical sensors offer a cost-effective and minimally invasive approach for in situ quantification of metal ions. Here, we developed and validated an electrochemical sensor based on bismuth-modified laser-induced graphene (LIG) electrodes for Al3+ quantitative detection in a range relevant to agriculture (1-300 ppm). Our results show a linear Al3+ detection range of 1.07-300 ppm with a variation coefficient of 5.3%, even in the presence of other metal ions (Pb2+, Cd2+, and Cu2+). The sensor offers a limit of detection (LOD) of 0.34 ppm and a limit of quantification (LOQ) of 1.07 ppm. We compared its accuracy for soil samples with pH < 4.8 to within 89-98% of spectroscopic methods (ICP-OES) and potentiometric titration. This technology's portability, easy to use, and cost-effectiveness make it a promising candidate for in situ quantification and remediation of Al3+ in agricultural soils and other complex matrices.


Assuntos
Grafite , Solo , Alumínio , Bismuto , Íons/química , Lasers , Técnicas Eletroquímicas
20.
Eur J Pharm Biopharm ; 198: 114259, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479563

RESUMO

Liquid crystalline nanoparticles (LCNPs) have gained much attention in cancer nanomedicines due to their unique features such as high surface area, storage stability, and sustained-release profile. In the current study, a novel LCNP for co-encapsulation of Bi2O3 and hydrophilic doxorubicin (DOX) was fabricated and functionalized with folic acid (FA) to achieve efficient tumor targeting toward CT-scan imaging and chemotherapy of melanoma in vitro and in vivo. LCNPs Bi2O3 NPs were prepared using glycerol monooleate-pluronic F-127 (GMO/PF127/water). Firstly, GMO/water were homogenized to prepare LC gel. Then, the stabilizer aqueous solution (PF127/Bi2O3/DOX) was added to the prepared LC gel and homogenized using homogenization and ultrasonication. The formulated NPs exhibited superior stability with encapsulation efficiency. High cytotoxicity and cellular internalization of the FA-Bi2O3-DOX-NPs were observed in comparison with Bi2O3-DOX-NPs and the free DOX in folate-receptor (FR) overexpressing cells (B16F10) in vitro. Moreover, ideal tumor suppression with increased survival rate were observed in tumorized mice treated with FA-Bi2O3-DOX-NPs compared to those treated with non-targeted one. On the other hand, the CT-imaging ability of the Bi2O3-DOX-NPs was tested inB16F10 tumor-bearing mice. The obtained data indicated a high potential of the developed targeted theranostic FA-Bi2O3-DOX-NPs for diagnostics and treatment of melanoma.


Assuntos
Bismuto , Melanoma , Nanopartículas , Animais , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Medicina de Precisão , Ácido Fólico/química , Doxorrubicina , Nanopartículas/química , Água , Linhagem Celular Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...