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1.
Int J Biol Macromol ; 269(Pt 2): 131956, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38692526

ABSTRACT

Water sources have become extremely scarce and contaminated by organic and inorganic industrial and agricultural pollutants as well as household wastes. Poisoning water resources by dyes and metals is a problem because contaminated water can leak into subsurface and surface sources, causing serious contamination and health problems. Therefore, developing wastewater treatment technologies is valuable. Today, hydrogels have attracted considerable attention owing to their broad applications. Hydrogels are polymeric network compositions with significant water-imbibing capacity. Hydrogels have potential applications in diverse fields such as biomedical, personal care products, pharmaceuticals, cosmetics, and biosensors. They can be prepared by using natural (biopolymers) and synthetic polymers. Synthetic polymer-based hydrogels obtained from petrochemicals are not environmentally benign; thus, abundant plant-based polysaccharides are found as more suitable compounds for making biodegradable hydrogels. Polysaccharides with many advantages such as non-toxicity, biodegradability, availability, inexpensiveness, etc. are widely employed for the preparation of environmentally friendly hydrogels. Polysaccharides-based hydrogels containing chitin, chitosan, gum, starch (St), etc. are employed to remove pollutants, metals, and dyes. Among these, St has attracted a lot of attention. St can be mixed with other compounds to make hydrogels, which remove dyes and metal ions to variable degrees of efficiency. Although St has numerous advantages, it suffers from drawbacks such as low stability, low water solubility, and fast degradability in water which limit its application as an environmental adsorbent. As an effective way to overcome these weaknesses, various modification approaches to form starch-based hydrogels (SBHs) employing different compounds have been reported. The preparation methods and applications of SBH adsorbents in organic dyes, hazardous materials, and toxic ions elimination from water resources have been comprehensively discussed in this review.


Subject(s)
Hydrogels , Starch , Hydrogels/chemistry , Starch/chemistry , Water Purification/methods , Water Pollutants, Chemical/chemistry , Adsorption , Coloring Agents/chemistry , Biodegradation, Environmental
2.
Science ; 382(6667): 164, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37824654
3.
Carbohydr Polym ; 318: 121102, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37479451

ABSTRACT

Gum-based hydrogels (GBHs) have been widely employed in diverse water purification processes due to their environmental properties, and high absorption capacity. More desired properties of GBHs such as biodegradability, biocompatibility, material cost, simplicity of manufacture, and wide range of uses have converted them into promising materials in water treatment processes. In this review, we explored the application of GBHs to remove pollutants from contaminated waters. Water resources are constantly being contaminated by a variety of harmful effluents such as heavy metals, dyes, and other dangerous substances. A practical way to remove chemical waste from water as a vital component is surface adsorption. Currently, hydrogels, three-dimensional polymeric networks, are quite popular for adsorption. They have more extensive uses in several industries, including biomedicine, water purification, agriculture, sanitary products, and biosensors. This review will help the researcher to understand the research gaps and drawbacks in this field, which will lead to further developments in the future.

4.
RSC Adv ; 13(27): 18715-18733, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37346956

ABSTRACT

C-N cross-coupling bond formation reactions have become valuable approaches to synthesizing anilines and their derivatives, known as important chemical compounds. Recent developments in this field have focused on versatile catalysts, simple operation methods, and green reaction conditions. This review article presents an overview of C-N cross-coupling reactions in pharmaceutical compound synthesis reports. Selected examples of N-arylation reactions of various nitrogen-based compounds and aryl halides are defined for preparing pharmaceutical molecules.

5.
Science ; 380(6645): 591, 2023 May 12.
Article in English | MEDLINE | ID: mdl-37167373
6.
Int J Biol Macromol ; 241: 124472, 2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37076069

ABSTRACT

Water sources are becoming increasingly scarce, and they are contaminated by industrial, residential, and agricultural waste-derived organic and inorganic contaminants. These contaminants may pollute the air, water, and soil and invade the ecosystem. Because carbon nanotubes (CNTs) can undergo surface modification, they can combine with other substances to create nanocomposites (NCs), including biopolymers, metal nanoparticles, proteins, and metal oxides. Furthermore, biopolymers are significant classes of organic materials that are widely used for various applications. They have drawn attention due to their benefits, such as environmental friendliness, availability, biocompatibility, safety, etc. As a result, the synthesis of a composite made of CNT and biopolymers can be very effective for various applications, especially those involving the environment. In this review, we reported environmental applications (including removal of dyes, nitro compounds, hazardous materials, toxic ions, etc.) of composites made of CNT and biopolymers such as lignin, cellulose, starch, chitosan, chitin, alginate, and gum. Also, the effect of different factors such as the medium pH, the pollutant concentration, temperature, and contact time on the adsorption capacity (AC) and the catalytic activity of the composite in the reduction or degradation of various pollutants has been systematically explained.


Subject(s)
Chitosan , Nanocomposites , Nanotubes, Carbon , Water Pollutants, Chemical , Chitosan/chemistry , Lignin/chemistry , Chitin , Cellulose , Nanotubes, Carbon/chemistry , Ecosystem , Alginates , Starch , Water , Water Pollutants, Chemical/chemistry , Nanocomposites/chemistry , Adsorption
7.
Int J Biol Macromol ; 239: 124135, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36965557

ABSTRACT

The second most abundant natural polymer in the earth's crust is chitosan (CS). The unique physical, chemical, structural, and mechanical features of this natural polymer have led to its increased application in a variety of fields such as medicine, catalysis, removal of pollutants, etc. To eliminate various pollutants, it is preferable to employ natural compounds as their use aids the removal of contaminants from the environment. Consequently, employing CS to eliminate contaminants is a viable choice. For this aim, CS can be applied as a template and support for metal nanoparticles (MNPs) and prevent the accumulation of MNPs as well as a reducing and stabilizing agent for the synthesis of MNPs. Among the pollutants present in nature, nitro compounds are an important and wide category of biological pollutants. 4-Nitrophenol (4-NP) is one of the nitro pollutants. There are different ways for the removal of 4-NP, but the best and most effective method for this purpose is the application of a metallic catalyst and a reducing agent. In this review, we report the recent developments regarding CS-supported metallic (nano)catalysts for the reduction of nitroaromatics such as nitrophenols, nitroaniline compounds, nitrobenzene, etc. in the presence of reducing agents. The metals investigated in this study include Ag, Au, Ni, Cu, Ru, Pt, Pd, etc.


Subject(s)
Chitosan , Environmental Pollutants , Metal Nanoparticles , Chitosan/chemistry , Nitrophenols/chemistry , Nitro Compounds , Metals , Reducing Agents , Catalysis , Metal Nanoparticles/chemistry , Environmental Pollutants/chemistry
8.
J Atr Fibrillation ; 10(1): 1579, 2017.
Article in English | MEDLINE | ID: mdl-29250222

ABSTRACT

BACKGROUND: Potential role of computerized decision support system on management of atrial fibrillation is not well understood. OBJECTIVES: To systematically review studies that evaluate the effects of computerized decision support systems and decision aids on aspects pertaining to atrial fibrillation. DATA SOURCES: We searched Medline, Scopus and Cochrane database. Last date of search was 2016, January 10. SELECTION CRITERIA: Computerized decision support systems that help manage atrial fibrillation and decision aids that provide useful knowledge for patients with atrial fibrillation and help them to self-care. DATA COLLECTION AND ANALYSIS: Two reviewers extracted data and summarized findings. Due to heterogeneity, meta-analysis was not feasible; mean differences of outcomes and confidence intervals for a difference between two Means were reported. RESULTS: Seven eligible studies were included in the final review. There was one observational study without controls, three observational studies with controls, one Non-Randomized Controlled Trial and two Randomized Controlled Trials. The interventions were three decision aids that were used by patients and four computerized decision support systems. Main outcomes of studies were: stroke events and major bleeding (one article), Changing doctor-nurse behavior (three articles), Time in therapeutic International Normalized Ratio range (one article), decision conflict scale (two articles), patient knowledge and anxiety about stroke and bleeding (two articles). CONCLUSIONS: A computerized decision support system may decrease decision conflict and increase knowledge of patients with atrial fibrillation (AF) about risks of AF and AF treatments. Effect of computerized decision support system on outcomes such as changing doctor-nurse behavior, anxiety about stroke and bleeding and stroke events could not be shown.We need more studies to evaluate the role of computerized decision support system in patients with atrial fibrillation.

9.
J Med Syst ; 42(2): 26, 2017 Dec 23.
Article in English | MEDLINE | ID: mdl-29273997

ABSTRACT

To evaluate the effect of a computerized Decision Support System (CDSS) on improving adherence to an anticoagulation guideline for the treatment of atrial fibrillation (AF). This study had an interrupted time series design. The adherence to the guideline was assessed at fortnightly (two weeks) intervals from January 2016 to January 2017, 6 months before and 6 months after intervention. Newly diagnosed patients with AF were included in the offices of ten cardiologists. Stroke and major bleeding risks were calculated by the CDSS which was implemented via a mobile application. Treatment recommendations based on the guideline were shown to cardiologists. The segmented regression model was used to evaluate the effect of CDSS on level and trend of guideline adherence for the treatment of AF. In our analysis, 373 patients were included. The trend of adherence to the anticoagulation guideline for the treatment of AF was stable in the pre-intervention phase. After the CDSS intervention, mean of the adherence to the guideline significantly increased from 48% to 65.5% (P-value < 0.0001). The trend of adherence to the guideline was stable in the post-intervention phase. Our results showed that the CDSS can improve adherence to the anticoagulation guideline for the treatment of AF. Registration ID: IRCT2016052528070N1.


Subject(s)
Anticoagulants/therapeutic use , Atrial Fibrillation/drug therapy , Decision Support Systems, Clinical/organization & administration , Guideline Adherence/statistics & numerical data , Stroke/prevention & control , Age Factors , Aged , Aged, 80 and over , Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Comorbidity , Female , Hemorrhage/chemically induced , Humans , Interrupted Time Series Analysis , Male , Middle Aged , Practice Guidelines as Topic , Practice Patterns, Physicians' , Risk Factors , Sex Factors
10.
Electron Physician ; 9(7): 4732-4736, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28894528

ABSTRACT

BACKGROUND: Atrial Fibrillation (AF) is the most common abnormal heart rhythm. AF patients usually use warfarin therapy. Safety and efficacy of warfarin are dependent on maintaining the International Normalized Ratio (INR) within the therapeutic range. OBJECTIVE: We will use a Short Message Service (SMS) to evaluate the effect of a reminder on carrying out the INR laboratory test in a timely manner. METHODS: This study (a Randomized Controlled Trial) will be done in Loghman hospital Tehran, Iran. Convenience sampling will be done and 400 AF patients that have inclusion criteria will be randomized equally to an intervention or control group. Patients in the intervention group will receive an SMS that will remind them of the INR test date. The SMS will be sent at 6 PM on the day before and 8 AM on the scheduled date but the patients of the control group will receive usual care without any SMS reminders. We will evaluate the effect of reminders on carrying out the INR test in a timely manner and maintaining the INR in the therapeutic range. Patients' follow-up will be done via telephone conversation to identify thromboembolic events, bleeding and mortality. The data will be analyzed by IBM SPSS version 24. We will use independent samples t-test or Mann-Whitney and Chi-square tests for the analyses of outcomes. DISCUSSION: This protocol describes the randomized control trial to study the effects of the SMS reminder system on adherence to the timing of INR test in AF patients treated with warfarin. The research will also form the basis for future decision support systems for monitoring of patients who receive oral anticoagulants. TRIAL REGISTRATION: Iranian Registry of Clinical Trials (http://www.irct.ir) was used to register the trial and IRCT ID was IRCT2016052528070N1. FUNDING: This research was supported by Mashhad University of Medical Sciences.

11.
Bull Environ Contam Toxicol ; 85(6): 589-92, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21069279

ABSTRACT

A photocatalytic process was evaluated for the removal of 2-Mercaptobenzoxazole (MBO) in wastewater. More than 90% of the MBO was removed by photocatalytic oxidation at about 3 h of irradiation time using Ag-ZnO nanocomposite thin film catalysts coated on glass by dip-coating. Ag-ZnO nanocomposite thin film was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM). The initial concentration of MBO was 20 ppm with optimum pH value of about 8.0. This investigation will give a new insight to understanding the mercaptan photodegradation in aquatic environment.


Subject(s)
Benzoxazoles/chemistry , Nanocomposites/chemistry , Odorants , Sulfhydryl Compounds/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/chemistry , Benzoxazoles/analysis , Glass , Hydrogen-Ion Concentration , Models, Chemical , Oxidation-Reduction , Photolysis , Silver/chemistry , Sulfhydryl Compounds/analysis , Water Pollutants, Chemical/analysis , Zinc Oxide/chemistry
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