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1.
Cureus ; 16(8): e66033, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39221324

RESUMO

Cohen syndrome (CS) is a rare autosomal recessive disorder marked by developmental delays, distinct facial features, and a variety of systemic manifestations. We present a case of a 28-year-old male previously misdiagnosed with Prader-Willi syndrome who exhibited recurrent generalized weakness, fever, fatigue, and significant hemoglobin drops requiring multiple blood transfusions due to thalassemia major. The patient displayed characteristic CS features, including developmental delays, distinct facial characteristics, morbid obesity, and heterochromia iridis. Severe gastrointestinal bleeding led to a diagnosis of ulcerative colitis (UC) via colonoscopy. Management included blood transfusions, hydrocortisone, mesalamine, and azathioprine, resulting in stabilized UC and improved overall health. CS presents with a spectrum of clinical features that overlap with other syndromic conditions, necessitating careful differential diagnosis. Early diagnosis and supportive care significantly improve quality of life and help manage complications effectively.

2.
Sci Rep ; 14(1): 18848, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143174

RESUMO

A novel chelating adsorbent based on (3-iminodiacetic acid) propyltriethoxysilane graphene oxide (IAT-GO) has been developed, showing exceptional promise for capturing lead. IAT-GO is made by combining a high-surface-area graphene oxide with a specially designed chelating ligand, which can selectively and efficiently remove lead. The synthesis of IAT-GO involves a two-step progression. In the first step, covalent bonds form between graphene oxide and (3-aminopropyl)-triethoxysilane (AT) through hydrolysis, condensation, and epoxide ring opening reactions. In the second step, nucleophilic substitution reactions occur between the primary amines and chloroacetic acid (CAA). A comprehensive suite of characterization techniques, including XPS, UV-Vis, XRD, Raman, FTIR, TEM, and SEM, provides detailed insights into the IAT-GO adsorbent's chemical composition and physical form, elucidating its intricate structure and morphology. Optimizing the experimental conditions for using the adsorbent material to remove Pb(II) ions from contaminated water revealed a maximum adsorption capacity of 124.0 mg/g at pH 5 and 30 min. The IAT-GO displays high selectivity for Pb(II) in a mixture of six metal ions containing 100 ppm of each one. Moreover, the IAT-GO shows 100% removal of Pb(II) for concentrations lower than 50 ppm. The excellent fit of the experimental data with the Langmuir adsorption isotherm and pseudo-second-order kinetic models (R2 > 99%) indicates that Pb(II) ion uptake onto the IAT-GO surface occurs via the monolayer formation of mercury ions. IAT-GO demonstrates exceptional potential as an innovative adsorbent for lead-contaminated water. Nitric acid (0.4 M) effectively regenerates the material, while its reusability remains impressive even after five cycles (> 97% removal efficiency). Therefore, this study highlights the development of a groundbreaking material, IAT-GO, with exceptional potential for remediating lead-contaminated water. Its high efficiency, selectivity, reusability, and cost-effectiveness make it a promising candidate for real-world applications.

3.
Anal Methods ; 16(30): 5191-5201, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38993152

RESUMO

The selective and sensitive detection of Al(III) is critically important for human health since the level of Al(III) is an indicator of many diseases in humans. Herein, we developed a simple and sensitive fluorescent sensor for the detection of Al(III) in an aqueous solution based on the fluorescence of hydroxyl-functionalized graphitic carbon nitride nanosheets (HO/g-CN). OH/g-CN nanosheets were synthesized via the thermal pyrolysis of 1,3,5-triazine-2,4,6-triamine (as raw material) at 550 °C for 2 hours, followed by thermal alkali treatment at 730 °C for 2 min. The fluorescence of HO/g-CN at 377 nm (at 290 nm excitation) can be quenched by Al(III) effectively and selectively, and the linear relationship between the concentration of Al(III) and fluorescence intensity is in the range of 1.85-14.82 µM with a detection limit of 0.272 µM. The fluorescence turn-off effect of the Al(III) ion on the prepared HO/g-CN nanosheets could be attributed to the presence of oxygen- and nitrogen-containing functional groups on the surface of HO/g-CN that have chelating interactions with Al(III), leading to quenching. The surface functional groups of OH/g-CN were confirmed using different characterization techniques (FTIR, EDX, and XPS). Moreover, the prepared HO/g-CN exhibited remarkable long-term fluorescence stability in water (>30 days) and minimal toxicity. Importantly, a prepared novel fluorescent sensor (HO/g-CN) was successfully applied for the detection and determination of Al(III) in commercially available crab (Brachyura) samples.

4.
Cureus ; 16(6): e63206, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39070423

RESUMO

Waardenburg syndrome (WS) is an autosomal dominant genetic disorder characterized by the absence of melanocytes, leading to distinctive pigmentary abnormalities and sensorineural hearing loss. This case report describes extremely rare concurrent anomalies in a preterm male infant diagnosed with WS type 1. The newborn, delivered prematurely at 35 weeks due to maternal complications, presented with multiple congenital anomalies and required immediate resuscitation. He exhibited hallmark features of WS, including a white forelock, dystopia canthorum, and bilateral sensorineural hearing loss. Genetic testing confirmed a PAX3 gene mutation. The infant experienced significant respiratory and feeding challenges, necessitating intensive care. Management included mechanical ventilation, surfactant therapy, phototherapy for hyperbilirubinemia, and broad-spectrum antibiotics for suspected sepsis. The cardiac assessment revealed multiple anomalies, such as a patent foramen ovale and left ventricular hypertrophy, while renal ultrasound identified multicystic dysplastic kidney and bilateral hydronephrosis. Multidisciplinary care facilitated the infant's stabilization, transition to oral feeding, and ongoing specialized care. WS type 1 is associated with mutations in the PAX3 gene and presents with diverse clinical manifestations. Although renal and cardiac anomalies are uncommon in WS, their presence in this case underscores the complexity of the syndrome. Early intervention for hearing impairment and genetic counseling are critical for optimal outcomes. This report highlights the importance of a comprehensive and interdisciplinary approach to managing infants with WS, addressing both typical and atypical manifestations. It is worth noting that effective management of WS in neonates requires prompt identification and treatment of associated complications.

5.
RSC Adv ; 14(22): 15281-15292, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38741953

RESUMO

A high-performance dye adsorbent of Mg/Al-layered double hydroxide modified water hyacinth hydrochar (MgAl@WH) was synthesized by a simple hydrothermal method. The surface functional groups, elemental composition, crystalline structure, and surface morphology of the prepared (MgAl@WH) were determined using different analytical techniques. The characterization results revealed that the (MgAl@WH) hydrochar surface offered more active adsorption sites, facilitating the mordant brown (anionic dye) adsorption, leading to its superior performance with much higher uptake capability (311.0 mg g-1 at 298 K) than Mg/Al double hydroxide nanosheets (MgAl DLHs, 80.2 mg g-1 at 298 K) and dried water hyacinth (WH, 10.0 mg g-1 at 298 K). The adsorption behavior of MgAL@WH follows the pseudo second order kinetic model (R2 = 0.999) and Langmuir isotherm model (R2 = 0.999). Moreover, MgAl@WH bonded efficiently with mordant brown dye via hydrogen bonding and interlayer anion exchange with monolayer formation. Additionally, the recycling tests revealed that the MgAl@WH can be reused over 10 cycles without significant change in the removal efficiency. Based on the obtained findings, Mg/Al-layered double hydroxide modified water hyacinth hydrochar (MgAl@WH), for its economic and environmental benefits, has recently been used as an efficient adsorbent to remediate industrial wastewater containing anionic dyes.

6.
RSC Adv ; 14(17): 11633-11642, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38605901

RESUMO

The natural gas production industry faces the problem of the proper disposal of produced water and its treatment with significantly advanced technologies to meet the minimum quality standard for irrigation activities, commercial purposes, and consumption by living organisms. This study describes an effective method for reducing the COD (chemical oxygen demand) content in formation water using different metal oxide nanoparticles such as iron oxide (FO), iron zinc oxide (FZO), and iron vanadium oxide (FVO) nanoparticles. These nanoparticles were synthesized and fully characterized using powder X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, dynamic light scattering particle size (DLS) analysis and zeta potential analysis. The experimental results revealed that the maximum reduction of COD content was 42.18% using FVO nanoparticles with a dose of 3 g L-1 at 25 °C and pH = 6. Compared to commercial products [Redoxy and Oxy(OXYSORB)], the synthesized FO, FZO, and FVO nanoparticles demonstrated their superiority by achieving excellent results in decreasing the COD content of wastewater associated with natural gas production by more than 86%. This study introduces a promising technique for decreasing the COD content using metal oxide nanoparticles, which are eco-friendly, bio-safe, cheap, and nontoxic materials, and improving the quality of wastewater associated with natural gas production for its safe disposal through sewage and treatment plants.

7.
RSC Adv ; 13(44): 31141-31150, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37881759

RESUMO

Novel selective and sensitive electrochemical sensors based on the modification of a carbon paste electrode (CPE) with novel amine- and thiol-functionalized multi-walled carbon nanotubes (MWCNT) have been developed for the detection and monitoring of uranyl ions in different real water samples. Multiwalled carbon nanotubes were grafted with 2-aminothiazole (AT/MWCNT) and melamine thiourea (MT/MWCNT) via an amidation reaction in the presence of dicyclohexyl carbodiimide (DCC) as a coupling agent. This modification for multiwalled carbon nanotubes has never been reported before. The amine and thiol groups were considered to be promising functional groups due to their high affinity toward coordination with uranyl ions. The modified multi-walled carbon nanotubes were characterized using different analytical techniques including FTIR, SEM, XPS, and elemental analysis. Subsequently, 10 wt% MT/MWCNT was mixed with 60 wt% graphite powder in the presence of 30 wt% paraffin oil to obtain a modified carbon paste electrode (MT/MWCNT/CPE). The electrochemical behavior and applications of the prepared sensors were examined using cyclic voltammetry, differential pulse anodic stripping voltammetry, and electrochemical impedance spectroscopy. The MT/MWCNT/CPE sensor exhibited a good linearity for UO22+ in the concentration range of 5.0 × 10-3 to 1.0 × 10-10 mol L-1 with low limits of detection (LOD = 2.1 × 10-11 mol L-1) and quantification (LOQ = 7 × 10-11 mol L-1). In addition, high precision (RSD = 2.7%), good reproducibility (RSD = 2.1%), and high stability (six weeks) were displayed. Finally, MT-MWCNT@CPE was successfully utilized to measure the uranyl ions in an actual water sample with excellent recoveries (97.8-99.3%). These results demonstrate that MT-MWCNT@CPE possesses appropriate accuracy and is appropriate for environmental applications.

8.
ACS Omega ; 8(21): 18901-18914, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37273622

RESUMO

Silver nanoparticles (Ag-NPs) exhibit vast potential in numerous applications, such as wastewater treatment and catalysis. In this study, we report the green synthesis of Ag-NPs using Acacia ehrenbergiana plant cortex extract to reduce cationic Rhodamine B (RhB) dye and for antibacterial and antifungal applications. The green synthesis of Ag-NPs involves three main phases: activation, growth, and termination. The shape and morphologies of the prepared Ag-NPs were studied through different analytical techniques. The results confirmed the successful preparation of Ag-NPs with a particle size distribution ranging from 1 to 40 nm. The Ag-NPs were used as a heterogeneous catalyst to reduce RhB dye from aqueous solutions in the presence of sodium borohydride (NaBH4). The results showed that 96% of catalytic reduction can be accomplished within 32 min using 20 µL of 0.05% Ag-NPs aqueous suspension in 100 µL of 1 mM RhB solution, 2 mL of deionized water, and 1 mL of 10 mM NaBH4 solution. The results followed a zero-order chemical kinetic (R2 = 0.98) with reaction rate constant k as 0.059 mol L-1 s-1. Furthermore, the Ag-NPs were used as antibacterial and antifungal agents against 16 Gram-positive and Gram-negative bacteria as well as 1 fungus. The green synthesis of Ag-NPs is environmentally friendly and inexpensive, as well as yields highly stabilized nanoparticles by phytochemicals. The substantial results of catalytic reductions and antimicrobial activity reflect the novelty of the prepared Ag-NPs. These nanoparticles entrench the dye and effectively remove the microorganisms from polluted water.

9.
Polymers (Basel) ; 15(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36850336

RESUMO

One of the most prevalent chronic infectious disorders is tooth decay. Acids produced when plaque bacteria break down sugar in the mouth cause tooth decay. Streptococcus mutans and Lactobacillus acidophilus are the most prominent species related to dental caries. Innovative biocidal agents that integrate with a biomaterial to prevent bacterial colonization have shown remarkable promise as a result of the rapid advancement of nanoscience and nanotechnology. In this study, Ulva lactuca was used as a cellulose source and reducing agent to synthesize nanocellulose and Ulva/Ag/cellulose/nanocomposites. The characterizations of nanocellulose and Ulva/Ag/cellulose/nanocomposites were tested for FT-IR, TEM, SEM, EDS, XRD, and zeta potential. Ulva/Ag/cellulose/nanocomposites and Ulva/nanocellulose, both blended with fluoride, were tested as an antibacterial against S. mutans ATCC 25175 and L. acidophilus CH-2. The results of the SEM proved that nanocellulose is filament-shaped, and FT-IR proved that the functional groups of Ulva/nanocellulose and Ulva/Ag/cellulose/nanocomposites and cellulose are relatively similar but present some small diffusion in peaks. The TEM image demonstrated that the more piratical size distribution of Ulva/Ag/cellulose/nanocomposites ranged from 15 to 20 nm, and Ulva/nanocellulose ranged from 10 to 15 nm. Ulva/Ag/cellulose/nanocomposites have higher negativity than Ulva/nanocellulose. Ulva/Ag/cellulose/nanocomposites and Ulva/nanocellulose possess antibacterial activity against S. mutans ATCC 25175 and L. acidophilus CH-2, but Ulva/Ag/cellulose/nanocomposites are more effective, followed by that blended with fluoride. It is possible to use Ulva/Ag/cellulose/nanocomposites as an antimicrobial agent when added to toothpaste. It is promising to discover an economic and safe nanocomposite product from a natural source with an antimicrobial agent that might be used against tooth bacteria.

10.
Microorganisms ; 12(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276170

RESUMO

Dental caries is an infectious oral disease caused by the presence of different bacteria in biofilms. Multidrug resistance (MDR) is a major challenge of dental caries treatment. Swabs were taken from 65 patients with dental caries in Makkah, Saudi Arabia. Swabs were cultivated on mitis salivarius agar and de Man, Rogosa, and Sharpe (MRS) agar. VITEK 2 was used for the identification of isolated bacteria. Antibiotic susceptibility testing of the isolated bacteria was performed using commercial antibiotic disks. Ulva lactuca was used as a reducing agent and cellulose source to create nanocellulose and Ag/cellulose nanocomposites. Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction spectroscopy (XRD) were used to characterize nanocellulose and Ag/cellulose nanocomposites. The results showed that most bacterial isolates were Streptococcus spp., followed by Staphylococcus spp. on mitis salivarius media. Lactobacillus spp. and Corynebacterium group f-1 were the bacterial isolates on de Man, Rogosa, and Sharpe (MRS) media. The antibiotic susceptibility test revealed resistance rates of 77%, 93%, 0, 83%, 79%, and 79% against penicillin G, Augmentin, metronidazole, ampicillin, ciprofloxacin, and cotrimoxazole, respectively. Ag/cellulose nanocomposites and Ag/cellulose nanocomposites with fluoride were the most effective antibacterial agents. The aim of this work was to assess the antibacterial activity of Ag/cellulose nanocomposites with and without fluoride against bacteria isolated from the oral cavities of patients with dental caries. This study demonstrated that Ag/cellulose nanocomposites have antibacterial properties against multidrug-resistant bacteria that cause dental caries.

11.
RSC Adv ; 12(55): 35587-35597, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36540397

RESUMO

This work reports the synthesis of an innovative multifunctional carbon nitride based adsorbent and its successful application for the removal of crystal violet (CV) and methylene blue (MB) from wastewater. The functionalized graphitic carbon nitride (f/g-CN) adsorbent was produced by the pyrolysis of melamine followed by thermal alkali treatment to introduce OH, NH x , and CN groups onto the graphitic carbon nitride (g-CN) surface. Experimental data obtained from batch tests revealed that the maximum adsorption capacities of g-CN and f/g-CN were found to be 28.9 and 239.0 mg g-1 for MB, and 163.0 and 532.0 mg g-1 for CV, respectively, at pH 8, 25 °C and after 90 min. This increase in adsorption capacity of f/g-CN can be explained by the presence of multiple functional groups in its structure. f/g-CN showed 100% removal for MB and CV with concentrations lower than 100 ppm and the equilibrium time required for the 100% removal of 500 ppb dye is 60 seconds. Additionally, the experimental data fitted well with the Langmuir isotherm model (R 2 = 0.992) and pseudo second order kinetic model (R 2 = 0.999) suggesting that the mechanism of adsorption is based on π-π stacking and electrostatic interactions between the NH x and OH groups of f/g-CN and dye molecules with monolayer formation. Moreover, a reusability test showed that the adsorption capacity remained at around 90% after 7 cycles. This work highlights the merits of the prepared adsorbent f/g-CN which is an eco-friendly, stable, efficient, and reusable adsorbent for removing cationic dyes from wastewater.

12.
ACS Omega ; 7(7): 6058-6069, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35224367

RESUMO

A novel chelating adsorbent, based on the functionalization of activated carbon (AC) derived from water hyacinth (WH) with melamine thiourea (MT) to form melamine thiourea-modified activated carbon (MT-MAC), is used for the effective removal of Hg2+, Pb2+, and Cd2+ from aqueous solution. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) theory confirm the successful functionalization of AC with the melamine thiourea chelating ligand through the amidation reaction between the carboxyl groups of oxidized activated carbon (OAC) and the amino groups of melamine thiourea (MT) in the presence of dicyclohexylcarbodiimide (DCC) as a coupling agent. The prepared MT-MAC exhibited extensive potential for the adsorption of the toxic metal ions Hg2+, Pb2+, and Cd2+ from wastewater. The MT-MAC showed high capacities for the adsorption of Hg2+ (292.6 mg·g-1), Pb2+ (237.4 mg·g-1), and Cd2+ (97.9 mg·g-1) from aqueous solution. Additionally, 100% removal efficiency of Hg2+ at pH 5.5 was observed at very low initial concentrations (25-1000 ppb).The experimental sorption data could be fitted well with the Langmuir isotherm model, suggesting a monolayer adsorption behavior. The kinetic data of the chemisorption mechanism realized by the melamine thiourea groups grafted onto the activated carbon surface have a perfect match with the pseudo-second-order (PSO) kinetic model. In a mixed solution of metal ions containing 50 ppm of each ion, MT-MAC showed a removal of 97.0% Hg2+, 68% Pb2+, 45.0% Cd2+, 17.0% Cu2+, 7.0% Ni2+, and 5.0% Zn2+. Consequently, MT-MAC has exceptional selectivity for Hg2+ ions from the mixed metal ion solutions. The MT-MAC adsorbent showed high stability even after three adsorption-desorption cycles. According to the results obtained, the use of the MT-MAC adsorbent for the adsorption of Pb2+, Hg2+, and Cd2+ metal ions from polluted water is promising.

13.
J Neurol Sci ; 423: 117358, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33653604

RESUMO

Reactivation of Human Endogenous Retrovirus K (HERV-K), subtype HML-2, has been associated with pathophysiology of amyotrophic lateral sclerosis (ALS). We aimed to assess the efficacy of antiretroviral therapy in inhibiting HML-2 in patients with ALS and a possible association between the change in HML-2 levels and clinical outcomes. We studied the effect of 24-weeks antiretroviral combination therapy with abacavir, lamivudine, and dolutegravir on HML-2 levels in 29 ALS patients. HML-2 levels decreased progressively over 24 weeks (P = 0.001) and rebounded within a week of stopping medications (P = 0.02). The majority of participants (82%), defined as "responders", experienced a decrease in HML-2 at week 24 of treatment compared to the pre-treatment levels. Differences in the evolution of some of the clinical outcomes could be seen between responders and non-responders: FVC decreased 23.69% (SE = 11.34) in non-responders and 12.71% (SE = 8.28) in responders. NPI score decreased 91.95% (SE = 6.32) in non-responders and 53.05% (SE = 10.06) in responders (P = 0.01). Thus, participants with a virological response to treatment showed a trend for slower progression of the illness. These findings further support the possible involvement of HML-2 in the clinical course of the disease.


Assuntos
Esclerose Lateral Amiotrófica , Retrovirus Endógenos , Infecções por HIV , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Infecções por HIV/tratamento farmacológico , Humanos
14.
RSC Adv ; 12(2): 1043-1050, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35425139

RESUMO

Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity. Materials for solar photothermal energy conversion are highly sought after for their cost savings, environmental friendliness and broad utility in many applications including domestic water heating and solar-driven desalination. Herein, we report the successful development of metal-free, low weight and cost effective functionalized carbonized cotton (CC) fibers for efficient solar water desalination and wastewater treatment. The CC fibers with nearly full solar spectrum absorption, efficient photo-thermal conversion and low-cost could provide excellent alternatives to the high-cost plasmonic-based materials for solar water desalination. We also report on a novel and simple device to mitigate the issues associated with conductive heat loss by utilizing the economically viable carbonized cotton materials as an irradiation surface placed on a low-density polyethylene foam that floats on the surface of seawater. The CC solar steam generation device exhibits average water evaporation rates of 0.9, 6.4 and 10.9 kg m-2 h-1 with impressive solar-to-vapor efficiencies of 59.2, 88.7 and 94.9% under 1, 5 and 8 sun illumination, respectively. Moreover, the device displays excellent durability showing stable evaporation rates over 10 steam generation cycles under 5 sun of solar intensity. Furthermore, the applicability of the CC device for the removal of organic dyes from contaminated water through solar steam generation is also demonstrated. The low-cost, simple design, high solar thermal evaporation efficiency, excellent stability and long-term durability make this CC device a perfect candidate for applications in seawater desalination and wastewater treatment by solar steam generation.

15.
Anal Chim Acta ; 1140: 111-121, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33218473

RESUMO

Here, a highly sensitive and selective copper ion (Cu2+) fluorescence sensor is reported. The Hematoporphyrin functionalized Graphene Oxide (HP-GO) fluorescence sensor were synthesized via esterification reaction between Graphene Oxide and Hematoporphyrin (HP). The HP-GO sensor was fully characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electrom Microscopy (SEM), UV-Vis spectroscopy, Transmission Electron Microscopy (TEM), Fluor meter spectroscopy, X-Ray photoelectron spectroscopy(XPS), and Raman spectroscopy measurements. The HP-GO sensor advertised two linear regions over the range of 0-1.18 × 103 nM and 3.93 × 103 to 47.27 nM of copper (II) with detection limit of 54 nM in the aqueous solution. The selectivity of HP-GO for Cu2+ is much higher than that of other metal ions due to the presence of aza macrocyclic ring on the surface of HP-GO which has a high binding affinity with Cu2+. Additionally, the HP-GO shows wide pH viable range (pH 6-10). The effect of other metal ions on the fluorescence intensity of the HP-GO was also studied and other metal ions show a low interference response in the detection of Cu2+. HP-GO sensor manifests advantages of high reproducibility (The quenched fluorescence of HP/GO-Cu can be recovered by EDTA), attractive long term fluorescence stability (>21 days) in water, also remarkable selectivity regarding number of metal ions (Na+, K+, Ca2+, Fe3+, Fe2+, Al3+, Pb2+, Mn2+, Mg2+, Co2+, Ni2+, Cr6+, Cd2+, Hg2+, and Zn2+), low toxicity and can detect Cu2+ in real water samples which acquire well for its promising in environmental applications.

16.
Trop Anim Health Prod ; 52(6): 3843-3854, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33047225

RESUMO

Herein, we provide the ecological niches of gastrointestinal nematode infections in Guilan, Mazandaran, and Golestan provinces. For this purpose, 2688 fecal specimens of sheep and cattle were subjected to the flotation method. For modeling procedure, the results were analyzed by considering 23 bioclimatic and environmental variables as well as 96 points/locations. Maximum entropy (model MaxEnt) was used to visualize the spatial distribution of gastrointestinal nematodes. The relative importance of all variables was also assessed by using jackknife analysis. The highest proportion of sheep infection with strongyle-type egg was observed in Golestan province (57.8%) and the lowest in Guilan province (49.5%), and eggs per gram (EPG) was around 21-29. The parasites with the highest proportion of infection in both domestic animals included strongyle-type eggs. Among the different bioclimatic and environmental variables, the biggest contributor to habitat suitability of the gastrointestinal nematode presence was found to be minimum temperature of the coldest month (Bio6), precipitation of driest quarter (Bio17), precipitation of coldest quarter (Bio19), and altitude. The MaxEnt model was able to provide a suitable guidance for predicting the probability distribution of gastrointestinal nematodes under bioclimatic and environmental variables, and the findings pave way for integrated gastrointestinal nematode surveillance and control strategies in the southern strip of Caspian Sea. In addition, the low intensity of gastrointestinal nematodiasis in ruminants may be associated with the frequent administration of anthelmintic drugs, where actions are needed to investigate drug resistance in the areas concerned and to provide anthelmintic drugs administration in a targeted manner.


Assuntos
Distribuição Animal , Doenças dos Bovinos/epidemiologia , Meio Ambiente , Enteropatias Parasitárias/veterinária , Nematoides/fisiologia , Infecções por Nematoides/veterinária , Doenças dos Ovinos/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Fezes/parasitologia , Incidência , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Irã (Geográfico)/epidemiologia , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Prevalência , Ovinos , Doenças dos Ovinos/parasitologia
17.
RSC Adv ; 10(62): 37883-37897, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-35515170

RESUMO

Heavy metal ions are highly toxic and widely spread as environmental pollutants. This work reports the development of two novel chelating adsorbents, based on the chemical modifications of graphene oxide and zirconium phosphate by functionalization with melamine-based chelating ligands for the effective and selective extraction of Hg(ii) and Pb(ii) from contaminated water sources. The first adsorbent melamine, thiourea-partially reduced graphene oxide (MT-PRGO) combines the heavier donor atom sulfur with the amine and triazine nitrogen's functional groups attached to the partially reduced GO nanosheets to effectively capture Hg(ii) ions from water. The MT-PRGO adsorbent shows high efficiency for the extraction of Hg(ii) with a capacity of 651 mg g-1 and very fast kinetics resulting in a 100% removal of Hg(ii) from 500 ppb and 50 ppm concentrations in 15 second and 30 min, respectively. The second adsorbent, melamine zirconium phosphate (M-ZrP), is designed to combine the amine and triazine nitrogen's functional groups of melamine with the hydroxyl active sites of zirconium phosphate to effectively capture Pb(ii) ions from water. The M-ZrP adsorbent shows exceptionally high adsorption affinity for Pb(ii) with a capacity of 681 mg g-1 and 1000 mg g-1 using an adsorbent dose of 1 g L-1 and 2 g L-1, respectively. The high adsorption capacity is also coupled with fast kinetics where the equilibrium time required for the 100% removal of Pb(ii) from 1 ppm, 100 ppm and 1000 ppm concentrations is 40 seconds, 5 min and 30 min, respectively using an adsorbent dose of 1 g L-1. In a mixture of six heavy metal ions at a concentration of 10 ppm, the removal efficiency is 100% for Pb(ii), 99% for Hg(ii), Cd(ii) and Zn(ii), 94% for Cu(ii), and 90% for Ni(ii) while at a higher concentration of 250 ppm the removal efficiency for Pb(ii) is 95% compared to 23% for Hg(ii) and less than 10% for the other ions. Because of the fast adsorption kinetics, high removal capacity, excellent regeneration, stability and reusability, the MT-PRGO and M-ZrP are proposed as top performing remediation adsorbents for the solid phase extraction of Hg(ii) and Pb(ii), respectively from contaminated water.

18.
ACS Omega ; 5(51): 33090-33100, 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33403271

RESUMO

Heavy metal ions represent one of the most toxic and environmentally harmful pollutants of water sources. This work reports the development of a novel chelating nitrogen-doped carboxylated porous carbon (ND-CPC) adsorbent for the effective removal of the heavy metal ions Pb(II), Hg(II), and Cr(VI) from contaminated and polluted water sources. The ND-CPC adsorbent is designed to combine four different types of nitrogen functional groups (graphitic, pyrrolic, pyridinic, and pyridine oxide) with the carboxylic acid functional groups within a high surface area of 1135 ± 20 m2/g of the porous carbon structure. The ND-CPC adsorbent shows exceptionally high adsorption affinity for Pb(II) with a capacity of 721 ± 14 mg/g in addition to high uptake values of 257 ± 5 and 104 ± 2 mg/g for Hg(II) and Cr(VI), respectively. The high adsorption capacity is also coupled with fast kinetics where the equilibrium time required for the 100% removal of Pb(II) from 50 ppb and 10 ppm concentrations is 30 s and 60 min, respectively. Even with the very high concentration of 700 ppm, 74% uptake of Pb(II) is achieved within 90 min. Removal efficiencies of 100% of Pb(II), 96% of Hg(II), 91% of Cu(II), 82% of Zn(II), 25% of Cd(II), and 13% of Ni(II) are achieved from a solution containing 10 ppm concentrations of these ions, thus demonstrating excellent selectivity for Pb(II), Hg(II), and Cu(II) ions. Regeneration of the ND-CPC adsorbent shows excellent desorption efficiencies of 99 and 95% for Pb(II) and Cr(VI) ions, respectively. Because of the fast adsorption kinetics, high removal capacity and excellent regeneration, stability, and reusability, the ND-CPC is proposed as a highly efficient remediation adsorbent for the solid-phase removal of Pb(II), Hg(II), and Cr(VI) from contaminated water.

19.
Nanoscale ; 10(39): 18531-18539, 2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-30221298

RESUMO

Water desalination and wastewater treatment via solar photothermal energy conversion are among the most important technologies to address the increasing pressing global water scarcity. Solar energy is the cleanest, most abundant, renewable natural resource available. Herein, we report the development of highly efficient, flexible, low weight, and cost effective Plasmonic Functionalized Cotton (PFC) nanocomposite materials for solar steam generation through the efficient evaporation of surface water pools. The PFC nanocomposites contain metallic nanoparticles that exhibit strong solar absorption followed by non-radiative relaxation causing the absorbed energy to be converted into heat for efficient water evaporation. The chemically modified cotton leads to a partial hydrophobic surface that allows the material to float on the water's surface and provide excellent thermal insulation properties in addition to facile and scalable synthesis. The PFC nanocomposites containing Au and Ag nanoparticles are demonstrated to be among the most efficient solar thermal converters reported to date for solar water desalination. The Au/Ag-PFC fibers exhibit average water evaporation rates of 1.4 and 11.3 kg m-2 h-1 with superb solar thermal efficiencies of up to 86.3% and 94.3% under 1 and 8 sun illumination, respectively. Furthermore, the Au/Ag-PFC fibers display stable evaporation rates over more than 10 repeated evaporation cycles without any performance decline under acidic solution at pH 2 or basic solution at pH 10. The successful application of the Au/Ag-PFC fibers for the removal of organic dyes from contaminated water through the solar steam generation is also demonstrated. The high solar thermal evaporation efficiency, excellent stability and long-time durability make the PFC nanocomposites excellent candidates for applications in seawater desalination and wastewater treatment by solar-steam generation.


Assuntos
Fibra de Algodão , Nanocompostos/química , Energia Solar , Águas Residuárias/química , Purificação da Água/métodos , Ouro/química , Prata/química
20.
Mult Scler Relat Disord ; 23: 17-22, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29730588

RESUMO

BACKGROUND: In primary studies with 3 T Magnets, phase sensitive reconstruction of T1-weighted inversion recovery (PSIR) have showed ability to depict the cervical multiple sclerosis (MS) lesions some of which may not be detected by short tau inversion recovery (STIR). Regarding to more availability of 1.5 T MRI, this study was designed to evaluate the eligibility of PSIR in 1.5 T for detection of spinal cord MS lesions. METHOD: In a study between September 2016 till March 2017 the patients with proven diagnosis of MS enrolled to the study. The standard protocol (sagittal STIR and T2W FSE and axial T2W FSE) as well as sagittal PSIR sequences were performed using a 1.5 T magnet. The images were studied and the lesions were localized and recorded as sharp or faint on each sequence. RESULTS: Of 25 patients (22 females and 3 males, with mean age of 33.5 ±â€¯9.8 years and mean disease duration of 5.4 ±â€¯3.9 years) 69 lesions in STIR, 53 lesions in T2W FSE, 47 lesions in Magnitude reconstruction of PSIR (Magnitude), and 30 lesions in phase sensitive (real) reconstruction PSIR were detected. A Wilcoxon signed-rank test showed STIR has a statistically significant higher detection rate of the plaques rather than other three sequences. (STIR and T2W FSE, Z = -4.000, p < 0.0001, STIR and Magnitude, Z = -4.690, p < 0.0001, STIR and PSIR, Z = -6.245, p = 0.002) Also, STIR had a statistically significant superiority in the boundary definition of the plaques rather than other three sequences. CONCLUSION: This study shows that in the setting of a 1.5 T magnet field, STIR significantly has a superiority over both of the PSIR reconstructions (i.e. real and magnitude) for the detection as well as the boundary definition of the cervical cord lesions of MS. These results have a good relevance to clinical practice by using MRI scanners and sequences routinely available, however, it is discrepant with other reports performed by 3 T Magnet fields.


Assuntos
Medula Cervical/diagnóstico por imagem , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino
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