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1.
Open Vet J ; 14(1): 500-511, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38633158

RESUMO

Background: One of the most challenging pests to control is the wild rat (Rattus norvegicus), which poses serious risks to both human health and the economy. Fertilizers are a more recent method of pest management with various action modes and are considered safe control agents when applied at low doses. Aim: The present study aimed to examine the toxicological impacts of the contaminated water with urea and camphor oil individually, post-treatment of rats with camphor oil after the pre-treatment with urea and post-treatment of rats with urea mixed with camphor oil after urea pre-treatment against the wild rats (R. norvegicus). Methods: The study extends to explore the influence of these treatments on the physicochemical parameters of the water administered by rats. Moreover, the effect of the most three toxic treatments was studied on the blood and renal functional parameters and the kidney tissue of rats after 21 days of treatment. Results: The study showed that urea was more potent than camphor oil when applied individually and increasing the concentration of urea in the pre-treatment or when combined with camphor oil in the post-treatment caused a significant increase in the mortality of rats. The post-treatment of rats with camphor oil only or camphor oil mixed with urea after the pre-treatment with urea induced a synergistic activity against rats. In addition, the exposed water to urea and camphor oil has been modified in physicochemical parameters and formed ulcers and harm to the kidneys of the exposed wild rats. Conclusion: This study significantly contributes to the ecological and toxicological potential risk indexes of urea and camphor oil together, which are restricted on the perceptible value relevance in the literature of water quality and renal pathology. Therefore, urea and camphor oil represent successful agents for the wild rat's control.


Assuntos
Cânfora , Ureia , Ratos , Animais , Humanos
2.
Food Chem ; 451: 139447, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38688097

RESUMO

An eco-friendly hydrothermal method synthesized VS2 nanosheets. Several spectroscopic and microscopic approaches (TEM) were used to characterize the produced VS2 nanosheet microstructure. VS2, Chitosan, and nanocomposite were used to immobilize watermelon (Citrullus lanatus) urease. Optimization using the Response Surface Methodology and the Box-Behnken design yielded immobilization efficiencies of 65.23 %, 72.52 %, and 87.68 % for chitosan, VS2, and nanocomposite, respectively. The analysis of variance confirmed the mathematical model's validity, enabling additional research. AFM, SEM, FTIR, Fluorescence microscopy, and Cary Eclipse Fluorescence Spectrometer showed urease conjugation to the matrix. During and after immobilization, FTIR spectra showed a dynamic connectivity of chemical processes and bonding. The nanocomposite outperformed VS2 and chitosan in pH and temperature. Chitosan and VS2-immobilized urease were more thermally stable than soluble urease, but the nanocomposite-urease system was even more resilient. The nanocomposite retained 60 % of its residual activity after three months of storage. It retains 91.8 % of its initial activity after 12 reuse cycles. Nanocomposite-immobilized urease measured milk urea at 23.62 mg/dl. This result was compared favorably to the gold standard p-dimethylaminobenzaldehyde spectrophotometric result of 20 mg/dl. The linear range is 5 to 70 mg/dl, with a LOD of 1.07 (±0.05) mg/dl and SD of less than 5 %. The nanocomposite's ksel coefficient for interferents was exceptionally low (ksel < 0.07), indicating urea detection sensitivity. Watermelon urease is suitable for dairy sector applications due to its availability, immobilization on nanocomposite, and reuse.


Assuntos
Quitosana , Citrullus , Enzimas Imobilizadas , Leite , Nanocompostos , Urease , Citrullus/química , Citrullus/enzimologia , Urease/química , Urease/metabolismo , Quitosana/química , Enzimas Imobilizadas/química , Nanocompostos/química , Leite/química , Animais , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Ureia/química
3.
Adv Skin Wound Care ; 37(5): 1-7, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648245

RESUMO

OBJECTIVE: To evaluate the cost-effectiveness of two 10% urea creams in patients with diabetic foot syndrome. METHODS: This was a prospective, longitudinal, single-center, randomized, double-blind, prospective clinical trial that evaluated the skin quality of 20 feet belonging to 10 patients with diabetic foot syndrome after the application of two 10% urea creams purchased from pharmacies and supermarkets. RESULTS: At follow-up, 19 (95%) of the participants' feet showed improved skin quality, irrespective of the cream applied. On visual inspection, participants had a decreased presence of xerosis, hyperkeratosis, and preulcerative signs such as subkeratotic bruising and areas of redness on the dorsum of the toes. At the 3-month follow-up, nine (90%) of the participants stated that they had continued to apply the cream as a method of self-management to prevent complications. CONCLUSIONS: Creams containing 10% urea purchased in supermarkets improve foot skin quality in patients with diabetic foot syndrome, regardless of their cost. Based on these findings, the authors recommend creams containing 10% urea as a self-management tool for patients with diabetic foot syndrome.


Assuntos
Análise Custo-Benefício , Pé Diabético , Creme para a Pele , Ureia , Humanos , Pé Diabético/tratamento farmacológico , Pé Diabético/economia , Feminino , Método Duplo-Cego , Masculino , Pessoa de Meia-Idade , Ureia/uso terapêutico , Estudos Prospectivos , Creme para a Pele/uso terapêutico , Idoso , Estudos Longitudinais , Resultado do Tratamento
4.
Clin Oral Investig ; 28(3): 189, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430338

RESUMO

OBJECTIVES: To assess color change efficacy and the adverse effects of varied over-the-counter (OTC) bleaching protocols. METHODOLOGY: The study included randomized clinical trials evaluating color changes from OTC bleaching agents. Nine databases were searched, including the partial capture of the grey literature. The RoB2 tool analyzed the individual risk of bias in the studies. Frequentist network meta-analyses compared treatments through common comparators (∆Eab* and ∆SGU color changes, and tooth sensitivity), integrating direct and indirect estimates and using the mean and risk differences as effect measures with respective 95% confidence intervals. The GRADE approach assessed the certainty of the evidence. RESULTS: Overall, 37 remaining studies constituted the qualitative analysis, and ten composed the meta-analyses. The total sample included 1,932 individuals. ∆Eab* was significantly higher in groups 6% hydrogen peroxide (HP) strips (≥ 14 h). ∆SGU was significantly higher in groups at-home 10% carbamide peroxide (CP) (≥ 14 h), followed by 6% HP strips (≥ 14 h) and 3% HP strips (≥ 14 h). At-home 10% CP (7-13 h) and placebo showed lower risks of tooth sensitivity without significant differences between these treatments. CONCLUSION: Considering the low level of evidence, OTC products presented satisfactory short-term effects on tooth bleaching compared to the placebo, with little to no impact on dentin hypersensitivity and gingival irritation. CLINICAL RELEVANCE: OTC products are proving to be practical alternatives for tooth whitening. However, patients should be advised about the possible risks of carrying out such procedures without professional supervision.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Humanos , Peróxido de Carbamida , Cor , Sensibilidade da Dentina/tratamento farmacológico , Peróxido de Hidrogênio , Ácido Hipocloroso , Metanálise em Rede , Medicamentos sem Prescrição/efeitos adversos , Peróxidos , Clareamento Dental/efeitos adversos , Clareamento Dental/métodos , Clareadores Dentários/efeitos adversos , Clareadores Dentários/farmacologia , Ureia
5.
J Appl Oral Sci ; 32: e20230336, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324805

RESUMO

OBJECTIVES: This study aimed to analyze the cost-effectiveness of whitening toothpastes and at-home bleaching for the treatment of tooth discoloration. METHODOLOGY: A cost-effectiveness economic analysis was conducted, and eight randomized clinical trials were selected based on the whitening agent product used: blue covarine dentifrices (BCD), hydrogen peroxide dentifrices (HPD), dentifrices without bleaching agents (CD, negative control), and 10% carbamide peroxide (CP10, positive control) for at-home bleaching. The consumer/patient perspective was adopted, macro-costing techniques were used and a decision tree model was performed considering the costs in the American and Brazilian markets. The color change evaluation (ΔE*ab) was used to calculate the effectiveness of tooth bleaching. A probabilistic analysis was performed using a Monte Carlo simulation and incremental cost-effectiveness ratios were obtained. RESULTS: CP10 resulted in the highest cost-effectiveness compared to the use of dentifrices in both markets. In Brazil, HPD was more cost-effective than BCD and CD. In the US, the increased costs of HPD and BCD did not generate any whitening benefit compared to CD. CONCLUSIONS: CP10 was more cost-effective than BCD and HPD for tooth bleaching from the perspectives of the Brazilian and American markets. Decision-making should consider the use of CP10 for treating tooth discoloration.


Assuntos
Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Humanos , Cor , Análise de Custo-Efetividade , Dentifrícios/uso terapêutico , Peróxido de Hidrogênio/uso terapêutico , Clareamento Dental/métodos , Clareadores Dentários/uso terapêutico , Descoloração de Dente/tratamento farmacológico , Cremes Dentais/uso terapêutico , Ureia , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Mymensingh Med J ; 33(1): 80-90, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163777

RESUMO

This observational study was carried out in the Department of Nephrology, Mymensingh Medical College Hospital, Bangladesh from January 2020 to December 2020. A total of 179 patients were included in this study according to inclusion and exclusion criteria. Informed written consent was taken from each patient. All patients were underwent detail history taking, thorough physical examination and relevant investigations. Data collection was conducted through a structured questionnaire. Collected data were analyzed using the statistical software SPSS 23.0. Mean age ±SD of the study patients was 47.06±14.1 with a majority in age group 41-50 years. Male predominance was observed with a male: female ratio of 2.19:1 and 68.7% male patients. Level of pre-dialysis, post-dialysis urea in the study population was 123.77±26.86mg/dl, 50.27±15.70mg/dl respectively and mean ±SD of Urea Reduction Ratio (URR) in hemodialysis (target >65.0%) was 67.2±1.9. Most of the 8 hours (two times) per week hemolysis patients could not achieve the target value of dialysis adequacy parameters. On the other hand, maximum people in 12 hours (three times) per week hemodialysis group achieved the target value of dialysis adequacy parameters. It is important to calculate Kt/V or URR and individualize the dialysis doses for each patient.


Assuntos
Falência Renal Crônica , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Falência Renal Crônica/terapia , Bangladesh , Diálise , Centros de Atenção Terciária , Diálise Renal , Ureia
7.
J Environ Manage ; 352: 119904, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38194877

RESUMO

Feeding the world's population while minimising the contribution of agriculture to climate change is one of the greatest challenges facing modern society. This challenge is particularly pronounced for dairy production where the carbon footprint of products and the mitigation costs are high, relative to other food stuffs. This paper reviews a number of mitigation measures that may be adopted by dairy farmers to reduce greenhouse gas emissions from their farms. A simulation model is developed to assess the cost-benefit of a range of mitigation measures. The model is applied to data from Ireland, a country with a large export-oriented dairy industry, for a range of farms including top, middle and bottom performing farms from a profitability perspective. The mitigation measures modelled included animal productivity, grass production and utilisation, better reproductive performance, early compact calving, reduced crude protein, decreased fertiliser N, protected urea, white clover, slurry tank cover and low emission slurry spreading (LESS). The results show that over half of the greenhouse gas abatement potential and most of the ammonia abatement potential were realised with cost-beneficial measures. Animal and feed-related measures that increased efficiency drove the abatement of GHG emissions. Low-emission slurry spreading was beneficial for the bottom and middle one-third of farms, while protected urea and reducing nitrogen use accounted for most of the ammonia abatement potential for the most profitable farms. Results showed that combining mitigation measures resulted in a decrease of 23%, 19%, and 12% in GHG emissions below 2020 levels for the bottom, middle, and top performing dairy farms, respectively. The findings imply that top dairy farms, that are already managed efficiently and optimally, may struggle to achieve the national and international GHG reduction targets with existing technologies and practices.


Assuntos
Gases , Gases de Efeito Estufa , Animais , Fazendas , Efeito Estufa , Gado , Amônia , Indústria de Laticínios/métodos , Ureia
8.
Nucl Med Biol ; 128-129: 108875, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38199184

RESUMO

INTRODUCTION: Copper-64 (64Cu, t1/2 = 12.7 h) is a positron emitter well suited for theranostic applications with beta-emitting 67Cu for targeted molecular imaging and radionuclide therapy. The present work aims to evaluate the radionuclidic purity and radiochemistry of 64Cu produced via the 68Zn(p,nα)64Cu nuclear reaction. Macrocyclic chelators DOTA, NOTA, TETA, and prostate-specific membrane antigen ligand PSMA I&T were radiolabeled with purified 64Cu and tested for in vitro stability. [64Cu]Cu-PSMA I&T was used to demonstrate in vivo PET imaging using 64Cu synthesized via the 68Zn(p,nα)64Cu production route and its suitability as a theranostic imaging partner alongside 67Cu therapy. METHODS: 64Cu was produced on a 24 MeV TR-24 cyclotron at a beam energy of 23.5 MeV and currents up to 70 µA using 200 mg 68Zn encapsulated within an aluminum­indium-graphite sealed solid target assembly. 64Cu semi-automated purification was performed using a NEPTIS Mosaic-LC synthesis unit employing CU, TBP, and TK201 (TrisKem) resins. Radionuclidic purity was measured by HPGe gamma spectroscopy, while ICP-OES assessed elemental purity. Radiolabeling was performed with NOTA at room temperature and DOTA, TETA, and PSMA I&T at 95 °C. 64Cu incorporation was studied by radio-TLC. 64Cu in vitro stability of [64Cu]Cu-NOTA, [64Cu]Cu-DOTA, [64Cu]Cu-TETA, and [64Cu]Cu-PSMA I&T was assessed at 37 °C from 0 to 72 h in human blood serum. Preclinical PET imaging was performed at 1, 24, and 48 h post-injection with [64Cu]Cu-PSMA I&T in LNCaP tumor-bearing mice and compared with [68Ga]Ga-PSMA I&T. RESULTS: Maximum purified activity of 4.9 GBq [64Cu]CuCl2 was obtained in 5 mL of pH 2-3 solution, with 2.9 GBq 64Cu concentrated in 0.5 mL. HPGe gamma spectroscopy of purified 64Cu detected <0.3 % co-produced 67Cu at EOB with no other radionuclidic impurities. ICP-OES elemental analysis determined <1 ppm Al, Zn, In, Fe, and Cu in the [64Cu]CuCl2 product. NOTA, DOTA, TETA, and PSMA I&T were radiolabeled with 64Cu, resulting in maximum molar activities of 164 ± 6 GBq/µmol, 155 ± 31 GBq/µmol, 266 ± 34 GBq/µmol, and 117 ± 2 GBq/µmol, respectively. PET imaging in PSMA-expressing LNCaP xenografts resulted in high tumor uptake (SUVmean = 1.65 ± 0.1) using [64Cu]Cu-PSMA I&T, while [68Ga]Ga-PSMA I&T yielded an SUVmean of 0.76 ± 0.14 after 60 min post-injection. CONCLUSIONS: 64Cu was purified in a small volume amenable for radiolabeling, with yields suitable for preclinical and clinical application. The 64Cu production and purification process and the favourable PET imaging properties confirm the 68Zn(p,nα)64Cu nuclear reaction as a viable 64Cu production route for facilities with access to a higher energy proton cyclotron, compared to using expensive 64Ni target material and the 64Ni(p,n)64Cu nuclear reaction. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE: Our 64Cu production technique provides an alternative production route with the potential to improve 64Cu availability for preclinical and clinical studies alongside 67Cu therapy.


Assuntos
Radioisótopos de Gálio , Neoplasias , Ureia/análogos & derivados , Masculino , Humanos , Animais , Camundongos , Análise Custo-Benefício , Compostos Radiofarmacêuticos/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos , Zinco
9.
Small Methods ; 8(3): e2301184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38019189

RESUMO

A portable sweat urea sensing system is a promising solution to satisfy the booming requirement of kidney function tele-monitoring. However, the complicated manufacturing route and the cumbersome electrochemical testing system still need to be improved to develop the urea point-of-care testing (POCT) and tele-monitoring devices. Here, a universal technical route based on a high-throughput automatic laser printing strategy for fabricating the portable integrated urea monitoring system is proposed. This integrated system includes a high-performance laser-printed urea sensing electrode, a planar three-electrode system, and a self-developed wireless mini-electrochemical workstation. A precursor donor layer is activated by laser scribing and in situ transferred into functional nanoparticles for the drop-on-demand printing of the urea sensing electrode. The obtained electrodes show high sensitivity, low detection limit, fast response time, high selectivity, good average recovery, and long-term stability for urea sensing. Additionally, a laser-induced graphene circuit-based miniature planar three-electrode system and a wireless mini-electrochemical workstation are designed for sensing data collection and transmitting, achieving real-time urea POCT and tele-monitoring. This scalable method provides a universal solution for high-throughput and ultra-fast fabrication of urea-sensing electrodes. The portable integrated urea monitoring system is a competitive option to achieve cost-effective POCT and tele-monitoring for kidney function.


Assuntos
Nanopartículas , Ureia , Análise Custo-Benefício , Técnicas Eletroquímicas/métodos , Monitorização Fisiológica
10.
Talanta ; 269: 125475, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039670

RESUMO

Fabric-based microfluidic analytical devices (µADs) have emerged as a promising material for replacing paper µADs thanks to their superior properties in terms of stretchability, mechanical strength, and their wide scope of applicability in wearable devices or embedded in garments. The major obstacle in their widespread use is the lack of a technique enabling their massive fabrication at a negligible-to-nil cost. In response, we report the development of a wax ink with proper thixotropic and hydrophobic properties, fully compatible with automatic screen-printing that allows the one step massive fabrication of microfluidics on a cotton/elastane fabric, with a printing resolution 400 µm (hydrophilic channel) and 1000 µm (hydrophobic barrier), without being necessary any post curing. The cost of the ink (50 g) and of each microfluidic device is ca. 2.3 and 0.007 €, respectively. The active component of the ink was a refined beeswax in a matrix based on ethyl cellulose in 2-butoxy ethyl acetate. Screen-printed fabric µADs were used for the simultaneous colorimetric determination of pH and urea in untreated human sweat by using multivariate regression analysis. This method enabled the direct measurement of urea using urease, regardless of the sweat's pH, and shows strong agreement with a reference method.


Assuntos
Microfluídica , Suor , Humanos , Colorimetria , Tinta , Ureia
11.
Environ Pollut ; 346: 123018, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38016590

RESUMO

The disposal of coffee shell waste on farmland, is a common practice that can causing the environmental and waste valuable resources. Carbonization has been identified as an effective method for transforming coffee shells into useful products that mitigate environmental pollution. Through the response surface methodology, the carbonization conditions of the coffee shells were optimized and its potential as a biochar-based slow-release urea fertilizer was explored. Experiments were conducted on coffee shell performance under varying carbonization conditions such as temperature (600-1000 °C), time (1-5 h), and heating rate (5-20 °C/min). The results indicated that the ideal urea adsorption was 56.3 mg/g, achieved under carbonization conditions of 2.83 h, 809 °C, and 15.3 °C/min. The optimal nutrient release rate within seven days was 45.4% under carbonization conditions of 3.19 h, 813 °C, and 15.0 °C/min. The infrared spectroscopy analysis indicates that carbonization conditions influenced the absorption peak intensity of coffee shell biochar, while the functional group types remain unchanged. The biochar exhibits diverse functional groups and abundant pores, making it a promising candidate for use as a biochar-based fertilizer material. Overall, the findings demonstrate an effective waste management approach that significantly reduces environmental pollutants while remediating pollution.


Assuntos
Café , Recuperação e Remediação Ambiental , Fertilizantes , Carvão Vegetal/química , Adsorção , Ureia/química
12.
Sci Total Environ ; 912: 169341, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38097080

RESUMO

The present study investigates the ecotoxicity of 7 biofertilizers, including biowaste-derived organic matrices. Real-field tests were conducted to assess the impacts of soil fertilization with sewage sludge digestate from high-solid thermophilic anaerobic digestion (HSTAD) compared to those obtained on non-amended and urea-fertilized soils. The physical-chemical and ecotoxic impact of HSTAD digestate on soil was monitored for 12 months, at 5 time points and 2 soil depths, on a maize field divided in 3 portions (non-treated, fertilized with urea, amended with digestate). The chemical and physical characteristics of the soil were previously analyzed for 3 years to provide a long-term outlook of the impacts of biofertilizer application. Seven bioindicators were utilized for direct (on whole soil) and indirect (on soil elutriates) ecotoxicological tests on fertilizers and amended soils, including plant seeds (Lepidium sativum, Sorghum saccharatum, and Sinapsis alba), the aquatic organism Daphnia magna, the alga Raphidocelis subcapitata, the luminescent bacterium Aliivibrio fischeri, and the Nematode Caenorhabditis elegans. No serious negative effects on soil fertilized with HSTAD digestate were evidenced. Conversely, bioassays rather showed positive effects, encouraging the utilization of HSTAD digestate in agriculture, considering the proper concentrations of use. The obtained data were interpolated and a test battery integrated index was generated, confirming the absence of ecotoxicological risk for the soils amended with the applied fertilizers. The long-term evolution of the physical-chemical soil characteristics (including the concentrations of potential contaminants) was similar for both HSTAD digestate and urea application as well as for non-fertilized soil, indicating no negative effects due to digestate application on land. On the contrary, digestate application improved the content of stabilized organic matter and nutrients in soil. This study proposes a more correct approach to ecotoxicity assessment of fertilized soils for biofertilizer evaluation and demonstrates the long-term safe application of HSTAD digestate on agricultural soil.


Assuntos
Fertilizantes , Solo , Solo/química , Fertilizantes/análise , Agricultura , Esgotos/química , Fertilização , Ureia
13.
Chem Biol Drug Des ; 102(6): 1458-1468, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37653693

RESUMO

Totally 15 novel flurbiprofen urea derivatives were synthesized bearing the thiadiazole ring. Their inhibition effects on tyrosinase were determined. 3c was found to be the strongest inhibitor with the IC50 value of 68.0 µM against tyrosinase. The enzyme inhibition types of the synthesized compounds were determined by examining the kinetic parameters. The inhibition type of 3c was determined as uncompetitive and the Ki value was calculated as 36.3 µM. Moreover, their cytotoxic effects on hepatocellular carcinoma (HepG2), colorectal carcinoma (HT-29), and melanoma (B16F10) cell lines were evaluated. According to the cytotoxicity results, 3l (IC50 = 14.11 µM) showed the highest cytotoxicity on the HT-29 cells, while 3o (IC50 = 4.22 µM) exhibited the strongest cytotoxic effect on HepG2 cell lines. Also, 3j (IC50 = 7.55 µM strongly affected B16F10. The effects of synthesized compounds on the healthy cell line were evaluated on the CCD-986Sk cell line. Molecular modelling studies have indicated the potential binding interactions of the uncompetitive inhibitor 3c with the enzyme-substrate complex.


Assuntos
Antineoplásicos , Flurbiprofeno , Tiadiazóis , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Flurbiprofeno/farmacologia , Ureia/farmacologia , Monofenol Mono-Oxigenase/metabolismo , Antineoplásicos/química , Células HT29
14.
Toxins (Basel) ; 15(9)2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37755973

RESUMO

Reliable models of renal failure in large animals are critical to the successful translation of the next generation of renal replacement therapies (RRT) into humans. While models exist for the induction of renal failure, none are optimized for the implantation of devices to the retroperitoneal vasculature. We successfully piloted an embolization-to-implantation protocol enabling the first implant of a silicon nanopore membrane hemodialyzer (SNMHD) in a swine renal failure model. Renal arterial embolization is a non-invasive approach to near-total nephrectomy that preserves retroperitoneal anatomy for device implants. Silicon nanopore membranes (SNM) are efficient blood-compatible membranes that enable novel approaches to RRT. Yucatan minipigs underwent staged bilateral renal arterial embolization to induce renal failure, managed by intermittent hemodialysis. A small-scale arteriovenous SNMHD prototype was implanted into the retroperitoneum. Dialysate catheters were tunneled externally for connection to a dialysate recirculation pump. SNMHD clearance was determined by intermittent sampling of recirculating dialysate. Creatinine and urea clearance through the SNMHD were 76-105 mL/min/m2 and 140-165 mL/min/m2, respectively, without albumin leakage. Normalized creatinine and urea clearance measured in the SNMHD may translate to a fully implantable clinical-scale device. This pilot study establishes a path toward therapeutic testing of the clinical-scale SNMHD and other implantable RRT devices.


Assuntos
Rins Artificiais , Insuficiência Renal , Humanos , Suínos , Animais , Creatinina , Projetos Piloto , Silício , Porco Miniatura , Soluções para Diálise , Ureia
15.
Bioresour Technol ; 388: 129783, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37722546

RESUMO

Adsorbents with excellent physicochemical properties and green synthetic routes are desired for efficient removal of Congo red (CR) wastewater. Hence, a novel approach was proposed within this work. Biochar NCBC obtained from Medulla Tetrapanacis was synthesized through co-modification with urea/calcium chloride. NCBC exhibited an enormous surface area (750.09 m2/g) and a micro-mesoporous composite structure. Higher nitrogen content was detected on the surface of NCBC (8.17%) compared to that of urea directly modified biochar (4.63%). Nitrogen observed on the surface of NCBC was presented as graphitic N, pyrrolic N, amine N as well as pyridinic N. Kinetic and isothermal investigations revealed the active sites on NCBC to be homogeneous and bind to CR mainly by chemisorption. Calculated maximum sorption of CR on NCBC was 2512.82 mg/g basing on Langmuir model. Moreover, the practicality of NCBC was further proved by the cultivation of Nelumbo nucifera Gaertn. and Penicillium.


Assuntos
Vermelho Congo , Poluentes Químicos da Água , Cloreto de Cálcio , Adsorção , Ureia , Carvão Vegetal/química , Nitrogênio/química , Poluentes Químicos da Água/química , Cinética
16.
Appl Environ Microbiol ; 89(8): e0179422, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37439668

RESUMO

Current production of traditional concrete requires enormous energy investment that accounts for approximately 5 to 8% of the world's annual CO2 production. Biocement is a building material that is already in industrial use and has the potential to rival traditional concrete as a more convenient and more environmentally friendly alternative. Biocement relies on biological structures (enzymes, cells, and/or cellular superstructures) to mineralize and bind particles in aggregate materials (e.g., sand and soil particles). Sporosarcina pasteurii is a workhorse organism for biocementation, but most research to date has focused on S. pasteurii as a building material rather than a biological system. In this review, we synthesize available materials science, microbiology, biochemistry, and cell biology evidence regarding biological CaCO3 precipitation and the role of microbes in microbially induced calcium carbonate precipitation (MICP) with a focus on S. pasteurii. Based on the available information, we provide a model that describes the molecular and cellular processes involved in converting feedstock material (urea and Ca2+) into cement. The model provides a foundational framework that we use to highlight particular targets for researchers as they proceed into optimizing the biology of MICP for biocement production.


Assuntos
Carbonato de Cálcio , Conservação de Recursos Energéticos , Microbiologia Industrial , Sporosarcina , Compostos de Amônio/metabolismo , Carbonato de Cálcio/economia , Carbonato de Cálcio/metabolismo , Precipitação Química , Sporosarcina/citologia , Sporosarcina/metabolismo , Ureia/metabolismo
17.
J Environ Manage ; 343: 118215, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37235993

RESUMO

This study aims to explore more sustainable ammonia production routes for urea and ammonium nitrate fertilizers to support the rising global food demand and help achieve the Net Zero Emissions scenario by 2050. The research uses process modelling tools and Life Cycle Assessment methodology to evaluate the technical and environmental performance of green ammonia production compared to blue ammonia production, both pathways coupled with urea and ammonium nitrate production processes. The blue ammonia scenario uses steam methane reforming for H2 production, while the sustainable approach scenarios consider water electrolysis with renewable resources (i.e., wind, hydro and photovoltaics) and nuclear power as a carbon-free source for H2 generation. The study assumes an annual productivity of 450,000 tons for both urea and ammonium nitrate. The environmental assessment uses mass and energy balance data derived from process modelling and simulation. A cradle-to-gate environmental evaluation is conducted using GaBi software and the Recipe 2016 impact assessment method. Results show that green ammonia production requires less raw materials but has higher energy consumption due to electrolytic H2 production (i.e., >90% of total energy requirements). The use of nuclear power achieves the highest reduction in global warming potential (i.e., 5.5 times for urea and 2.5 times for ammonium nitrate production processes), while hydro power coupled with electrolytic H2 production shows lower environmental impacts in most categories (i.e., six out of ten impact categories). Overall, the sustainable scenarios prove to be suitable alternatives for fertilizer production towards achieving a more sustainable future.


Assuntos
Amônia , Ureia , Agricultura/métodos , Meio Ambiente , Fertilizantes/análise
18.
J Environ Manage ; 342: 118196, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209646

RESUMO

The combined pollution of heavy metals and organic compounds usually occurs simultaneously and induces high toxicity. The technology of simultaneous removal of combined pollution is lacking and the removal mechanism is not clear. Sulfadiazine (SD), a widely used antibiotic, was used as a model contaminant. Urea modified sludge-based biochar (USBC) was prepared and used to catalyze H2O2 to remove the combined pollution of Cu2+ and sulfadiazine (SD) without causing secondary pollution. After 2 h, the removal rates of SD and Cu2+ were 100 and 64.8%, respectively. Cu2+ adsorbed on the surface of USBC accelerated the activation of H2O2 by the USBC catalyzed by CO bond to produce hydroxyl radical (•OH) and single oxygen (1O2) to degrade SD. Twenty-three intermediate products were detected, most of which were completely decomposed into CO2 and H2O. The toxicity was significantly reduced in the combined polluted system. This study highlights the potential of the low-cost technology based on sludge reuse and its inherent significance in reducing the toxic risk of combined pollution in the environment.


Assuntos
Cobre , Peróxido de Hidrogênio , Cobre/química , Peróxido de Hidrogênio/química , Sulfadiazina , Esgotos , Ureia , Carvão Vegetal/química , Oxigênio , Catálise , Estresse Oxidativo
19.
Int J Biol Macromol ; 242(Pt 2): 124858, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178883

RESUMO

Modern agriculture presents new requirements of low cost, high water retention and degradability for superabsorbent and slow-release fertilizers. In this study, carrageenan (CG), acrylic acid (AA), N, N '-methylene diacrylamide (MBA), urea and ammonium persulfate (APS) were used as raw materials. A kind of high water absorption, water retention, nitrogen slow release and biodegradable carrageenan superabsorbent (CG-SA) was prepared by grafting copolymerization. The optimal CG-SA was obtained with a water absorption rate of 680.45 g/g by orthogonal L18(3)7 experiments and single-factor experiments. The water absorption behavior of CG-SA in deionized water and salt solution were studied. The CG-SA was characterized before and after degradation by FTIR, SEM. The nitrogen release behavior and kinetic characteristics of CG-SA were investigated. In addition, CG-SA degraded 58.33 % and 64.35 % in soil at 25 °C and 35 °C after 28 days. All the results indicated that the low-cost and degradable CG-SA can achieve simultaneous slow release of water and nutrients, which is expected to be widely used as a new water-fertilizer integration technology in arid and poor areas.


Assuntos
Fertilizantes , Ureia , Carragenina , Fertilizantes/análise , Nitrogênio , Solo , Água
20.
Molecules ; 28(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37049892

RESUMO

The objective of this study was to synthesize a novel choline hydroxide ionic liquid-based tooth bleaching gel. Ionic liquid-based gels were synthesized and characterized using FTIR along with pH testing. Tooth sample preparation was carried out in line with ISO 28399:2020. The effects of synthesized gels on tooth samples were tested. Tooth samples were stained and grouped into three experimental groups: EAI (22% choline hydroxide gel), EAII (44% choline hydroxide gel), and EB (choline citrate gel) and two control groups: CA (commercial at-home 16% carbamide peroxide gel) and CB (deionized water). The tooth color analysis, which included shade matching with the Vitapan shade guide (n = 2), and digital colorimetric analysis (n = 2) were evaluated. The surface characteristics and hardness were analyzed with 3D optical profilometry, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), and Microhardness testing (n = 3), respectively. The tooth color analysis (Vitapan shade guide) revealed that all the tooth samples treated with synthesized choline citrate gel (EB) showed an A1 shade as compared to the other four groups, giving a range of shades. An analysis of the ΔE values from digital colorimetry; EAI, EAII, CA, and CB showed ΔE values in a range that was clinically perceptible at a glance. However, EB showed the highest value of ΔE. The mean microhardness values for the five groups showed that the effects of three experimental gels i.e., 44% choline hydroxide, 22% choline hydroxide, and choline citrate, on the microhardness of the tooth samples were similar to that of the positive control, which comprised commercial at-home 16% carbamide peroxide gel. SEM with EDX of three tested subgroups was closely related in surface profile, elemental composition, and Ca/P ratio. The roughness average values from optical profilometry of four tested subgroups lie within approximately a similar range, showing a statistically insignificant difference (p > 0.05) between the tested subgroups. The synthesized novel experimental tooth bleaching gels displayed similar tooth bleaching actions without any deleterious effects on the surface characteristics and microhardness of the treated tooth samples when compared with the commercial at-home tooth bleaching gel.


Assuntos
Líquidos Iônicos , Clareamento Dental , Clareamento Dental/métodos , Peróxido de Carbamida , Peróxidos/química , Ureia/química , Análise Custo-Benefício , Géis , Peróxido de Hidrogênio/química
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