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Current research on coronavirus 2 disease (SARS-CoV-2) has been focused on developing reliable gold nanomaterials and methods for the detection of viral spike protein (S-proteins). Here, we describe the fluorescence quenching of spike proteins in the presence of robust gold-aryl nanoparticles. The obtained results demonstrated a strong binding affinity between S-proteins and tryptophan immobilized on gold-carbon nanoparticles (Trp-AuNPs) based on the binding constant value of 11.098 M−1. Förster non-radiative energy transfer (FRET) calculations showed an average binding distance of r = 3.06 nm and a critical energy transfer distance of R0 = 2.5 nm. Time-resolved fluorescence studies of conjugated S-proteins onto Trp-AuNPs revealed a short fluorescence lifetime and dynamic quenching. [ABSTRACT FROM AUTHOR]

Indoleamine 2, 3-dioxygenase 1 (IDO1) is commonly expressed by cancers as a mechanism for evading the immune system. Preclinical and clinical studies have indicated the potential of combining IDO1 inhibitors with immune therapies for the treatment of cancer, strengthening an interest in the discovery of novel dioxygenase inhibitors for reversing tumour-mediated immune suppression. To facilitate the discovery, development and investigation of novel small molecule inhibitors of IDO1 and its hepatic isozyme tryptophan dioxygenase (TDO2), murine tumour cells were engineered to selectively express either murine or human IDO1 and TDO2 for use as tools to dissect both the species specificity and isoenzyme selectivity of newly discovered inhibitors. Lewis lung carcinoma (LLTC) lines were engineered to express either murine or human IDO1 for use to test species selectivity of the novel inhibitors; in addition, GL261 glioma lines were engineered to express either human IDO1 or human TDO2 and used to test the isoenzyme selectivity of individual inhibitors in cell-based assays. The 20 most potent inhibitors against recombinant human IDO1 enzyme, discovered from a commissioned screening of 40,000 compounds in the Australian WEHI compound library, returned comparable IC50 values against murine or human IDO1 in cell-based assays using the LLTC-mIDO1 and LLTC-hIDO1 line, respectively. To test the in vivo activity of the hits, transfected lines were inoculated into syngeneic C57Bl/6 mice. Individual LLTC-hIDO1 tumours showed variable expression of human IDO1 in contrast to GL261-hIDO1 tumours which were homogenous in their IDO1 expression and were subsequently used for in vivo studies. W-0019482, the most potent IDO1 inhibitor identified from cell-based assays, reduced plasma and intratumoural ratios of kynurenine to tryptophan (K:T) and delayed the growth of subcutaneous GL261-hIDO1 tumours in mice. Synthetic modification of W-0019482 generated analogues with dual IDO1/TDO2 inhibitory activity, as well as inhibitors that were selective for either TDO2 or IDO1. These results demonstrate the versatility of W-0019482 as a lead in generating all three subclasses of tryptophan dioxygenase inhibitors which can be applied for investigating the individual roles and interactions between IDO1 and TDO2 in driving cancer-mediated immune suppression. [ABSTRACT FROM AUTHOR]

Zeolite frameworks provide an excellent host for metal ions like silver, gold, and copper. The modified zeolites were characterized using various spectroscopic techniques, including low-temperature solid-state luminescence, Raman and FT-EXAFS, SEM–EDS, X-Ray fluorescence, along with theoretical calculations. Analyses indicate the formation of metal ion oligomers for the studied silver- and gold-incorporated zeolite catalysts. The oligomer-incorporated zeolites were found to provide strong photocatalytic behavior towards pesticides and chlorinated organic pollutants. Various catalytic parameters like the metal composition, pore diameter, structure, surface area as well as proposed kinetic mechanisms for the photocatalytic reactions are presented in this mini review. [ABSTRACT FROM AUTHOR]

Biocompatible and luminescent nanostructures synthesized by capping gold-carbon nanoparticles (HOOC-4-C6H4-AuNPs) with amino acids tyrosine, tryptophan, and cysteine were used for the quantitative estimation of ranitidine (RNH), a peptic ulcer and gastroesophageal reflux drug. We applied a fluorescence quenching mechanism to investigate the viability of the energy transfer based on gold-carbon nanosensors. Förster resonance energy transfer (FRET) calculations showed a donor–acceptor distance of 1.69 nm (Tyr@AuNPs), 2.27 nm (Trp@AuNPs), and 2.32 nm (Cys@AuNPs). The constant time-resolved fluorescence lifetime measurements supported the static quenching nature. This method was successfully utilized in the detection and quantification of RNH, with a limit of detection (LOD) of 0.174, 0.56, and 0.332 μM for Tyr@AuNP, Trp@AuNP, and Cys@AuNP bioconjugates, respectively. This approach was also successful in the quantification of RNH in spiked serum samples. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are of great interest to researchers in chemistry and material science due to their various chemical and physical properties, which include high surface area, augmented adsorption/desorption kinetics, biocompatibility, and functional tunability. The structurally diverse 1-D, 2-D, and 3-D metal-organic frameworks have found applications in chemical sensing and several other fields, such as energy applications, biomedicine, and catalysis. In this review article, we address recent research advances in the use of metal-organic-framework-based nanocomposite materials as luminescent sensors for detecting various metal ions in aqueous biological and environmental samples. [ABSTRACT FROM AUTHOR]

Silver clusters were introduced into the framework of zeolite Y. Low-temperature solid-state luminescence indicates the formation of silver–silver excimers and exciplexes that were found to be activated at 250 and 300 nm, respectively. The photodegradation of a persistent halogenated organic pollutant, namely 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), was studied in the presence and absence of two catalysts, namely including AgY1 and AgY2, under mid- and high energy: 302 and 254 nm, respectively. The results showed that in the absence of a catalyst, degradation under 254-nm UV light resulted in changes to the peak intensity as well as energy, while the 302-nm profile showed only loss in peak intensity. In the presence of either catalyst, a higher rate of degradation of the 2,3,7,8-TCDF was observed. The amount of the adsorbed 2,3,7,8-TCDF on the AgY1 and AgY2 catalyst was estimated to reach 37.9 and 18.9% of its initial concentration, respectively. The toxicity of the intermediate and resultant products was further analyzed with the aid of an enzyme-linked immunosorbent assay. The optical density showed that in contrast to all the samples, the TCDF irradiated with 254 nm in the presence of AgY2 was high at 40 min inferring a decrease in toxicity of the resultant product. The present work shows an innovative and cost-efficient technique for the removal of dioxins and furans from water sources. [ABSTRACT FROM AUTHOR]

Phosphonium iodobismuthates(III) (MePh3P)3[Bi3I12] (1) and (Ph4P)3[Bi3I12] (2) were prepared, and X-ray crystal structures were determined for both complexes. Photophysical behavior of both complexes was determined via diffuse reflectance spectroscopy and photoluminescence measurements. Photoluminescence results for complex 2 revealed room temperature emission, which has been rarely reported by bismuth compounds. Low-temperature luminescence scans further indicated a dramatic change in emission properties between the MePh3P+ and Ph4P+ complexes. Photodegradation studies using both ultraviolet and visible light were carried out to determine the light-absorbing capabilities of both complexes. Visible light-promoted degradation studies in the presence of catalytic amounts of 1 and 2 showed significant degradation of aqueous methylene blue and carbaryl solutions over a period of 1 h. The reported photoirradiation studies indicated the phosphonium iodobismuthate salts promote visible light harvesting and facilitate catalytic dye photosensitization. This sensitization allows for the degradation of organic pollutants in the presence of visible light and suggests coupling with fluorescence dyes is viable in photovoltaic applications. [ABSTRACT FROM AUTHOR]

Mixed silver–zinc doped in zeolite Y was prepared via cation exchange process. Two samples with various silver and zinc contents were prepared as well as two samples modified with microwave treatment before the calcination process. The prepared samples behave as good adsorbents towards fenoxicarb where up to 30% of the pesticide was removed from solutions upon mixing for one minute. In addition, all of the modified materials tend to enhance the photo-degradation of fenoxicarb when irradiated at 254 nm UV light. The study indicates that Ag-ZnY1 (10.7% Ag and 10.32% Zn) provides the best catalytic activity towards the degradation of fenoxycarb where the rate constant was 0.041 min-1 compared to the observed rate constant of 0.0162 min-1 for the similar test without a catalyst. In addition, both microwave samples provide an enhancement in the photo-degradation by 1.6–1.7 times compared to the zeolite-free samples. The data showed that silver played the major role in the observed catalytic activity. For example, the rate constant of the Ag-ZnY1M sample (1.8% Ag and 0.20% Zn) was 0.0283 min-1 while the reaction proceeds with a rate constant of 0.0270 min-1 when Ag-ZnY2M (0.90% Ag and 0.30% Zn) catalyst was used. GC-MS analysis of the irradiated solution of fenoxycarb for 60 min showed the formation of 4-(2-aminoethoxy)phenol ethane as the major product. [ABSTRACT FROM AUTHOR]

Background: One of the features of Malta fever is diversity of hematologic manifestations. The Aim of This study was to evaluate hematologic findings of brucellosis and its association with titer of wright agglutination test. Materials & Methods: This study was a cross - sectional and analytical study that was conducted on 189 patients with brucellosis in the Arak in 2011. The diagnostic criteria of the disease were the Wright test and 2-Mercaptoethanol (2ME) agglutinin assay with titers greater than 1:160 and 1:80, respectively, and clinical symptoms compatible with brucellosis. Data were obtained from patient records and were analyzed with SPSS version 16. Results: From 189 patients with Brucellosis who were enrolled in study 67.8% was male, Mean age in men was 37.8±23.3 years and in women 36.9±15.3 years. Erythrocyte sedimentation rate in 44.5% was between 21- 40 and in 2.1% was above 60. 45% of patients had qualitative CRP levels higher than +2. Leukopenia in 9%, anemia 19%, thrombocytopenia 7.4% was seen. In 27.8% the lymphocyte cell count was predominant. 7.5% of patients had eosinophilia of more than 5% and 4.8% with bicytopenia and 1.6% had pancytopenia. The association between titer of wright test and sex, ESR, leucopenia, thrombocytopenia and anemia was not observed, (P>0.05) but with CRP>1+ (P=0.0001) and age over 45 years (P= 0.017 association was significant. Conclusion: Brucellosis should be considered as a differential diagnosis among patients whose blood picture reveals anemia, leukopenia, thrombocytopenia or pancytopenia. There is no relation between wright titer and hematologic manifestation. In comparison with similar studies in other countries, hematologic abnormality is lower in our patients. [ABSTRACT FROM AUTHOR]

Background: Multi-drug resistance due to Acinetobacter baumannii strains has become a significant challenge. Efflux pump plays a vital role in the development of resistance in this bacteria. The aim of this study was to evaluate the frequency of the AdeABC efflux pump genes and its role in resistance to imipenem in clinical isolates of A.baumannii. Materials and methods: A total of 56 isolates of A.baumannii were collected from different clinical specimens of Valiasr hospital in the Arak -Iran and all isolates were identified by standard biochemical tests. The Antimicrobial susceptibility patterns were determined by disk diffusion method and minimum inhibitory concentrations of imipenemin via E-test strips with and without CCCP efflux pump inhibitor were determined according to CLSI guidelines. The PCR test was used to detect the AdeABC efflux pump genes in isolates. Results: All A.bumannii isolates were resistant to cefotaxim, ceftazidim, cefepim, cefoxitin, azteronam, piperacillin-tazobactam and ciprofloxacin, as well as all isolates were resistant to imipenem according to the results of the E-test method. Imipenem MIC with efflux pump inhibitor not reduced in all isolates and showed no differences in imipenem activity. The adeA, adeB and adeC genes were found in 100%, 100% and 96.5% of isolates, respectively. Conclusion: AdeABC efflux system contributes to resistance to other antibiotics and resistance to imipenem has not been involved with this efflux system in A.baumanni isolates in current study and other mechanism such as carbapenemase enzymes play vital role to imipenem resistance in A. baumanni isolates. [ABSTRACT FROM AUTHOR]

Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 gNm-2 preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 gNm-2. No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE), nitrogen recovery efficiency (NRE), N uptake, and rice yield when legume crops were grown in rotation with rice. Rice after winged bean grown with N at the rate of 4gNm-2 achieved significantly higher NRE, NAE, and N uptake in both years. Rice after winged bean grown without N fertilizer produced 13-23% higher grain yield than rice after fallow rotation with 8 gNm-2.The results revealed that rice after winged bean without fertilizer and rice after long bean with N fertilizer at the rate of 4 gNm-2 can produce rice yield equivalent to that of rice after fallow with N fertilizer at rates of 8 gNm-2.The NAE, NRE, and harvest index values for rice after winged bean or other legume crop rotation indicated a positive response for rice production without deteriorating soil fertility. [ABSTRACT FROM AUTHOR]

Background: Soil contamination by copper (Cu) and lead (Pb) is a widespread environmental problem. For phytoextraction to be successful and viable in environmental remediation, strategies that can improve plant uptake must be identified. In the present study we investigated the use of nitrogen (N) fertilizer as an efficient way to enhance accumulation of Cu and Pb from contaminated industrial soils into amaranth, Indian mustard and sunflower. Methods/Principal Findings: Plants were grown in a greenhouse and fertilized with N fertilizer at rates of 0, 190 and 380 mg kg−1 soil. Shoots, roots and total accumulation of Cu and Pb, transfer factor (TF), translocation index were assessed to evaluate the transport and translocation ability of tested plants. Addition of N fertilizer acidified the industrial soil and caused the pH to decrease to 5.5 from an initial pH of 6.9. Industrial soil amended with N fertilizer resulted in the highest accumulation of Pb and Cu (for Pb 10.1–15.5 mg kg−1, for Cu 11.6–16.8 mg kg−1) in the shoots, which was two to four folds higher relative to the concentration in roots in all the three plants used. Sunflower removed significantly higher Pb (50–54%) and Cu (34–38%) followed by amaranth and Indian mustard from industrial soils with the application of N fertilizer. The TF was <1 while the shoot and root concentration (SC/RC) ratios of Pb and Cu were between 1.3–4.3 and 1.8–3.8, respectively, regardless of plant species. Conclusions: Sunflower is the best plant species to carry out phytoextraction of Pb and Cu. In contrast, Pb and Cu removal by Indian mustard and amaranth shows great potential as quick and short duration vegetable crops. The results suggest that the application of N fertilizer in contaminated industrial soil is an effective amendment for the phytoextraction of Pb and Cu from contaminated industrial soils. [ABSTRACT FROM AUTHOR]

g (I) nanoclusters doped in mordenite zeolite were prepared and spectroscopically analyzed. Strong luminescence emission that is dependent on the excitation wavelength was observed. These variations in the emission modes are due to the site selective luminescence where various luminophores might be excited upon selecting the proper excitation wavelength. The selected material was found to have strong affinity to remove the quinalphos pesticide, which is widely used for the protection of several vegetable and fruit crops, from water bodies. HPLC and GC-MS techniques were used to follow the kinetic data and to identify the photodecomposition products, respectively. The photodecomposition of quinalphos in the presence of the silver doped mordenite catalyst gives different products compared to the irradiation of quinalphos without catalyst. The presence of the Ag-mordenite catalyst not only adsorbs the quinalphos from the solution but it also reduces its toxic effect as tested on the fruit fly ( Drosophila melanogaster). [ABSTRACT FROM AUTHOR]

A chemoluminescent sensor utilizing the substrate 2,6-pyridinedicarboxaldehydebis(o-hydroxyphenylimine) (S1) was developed for low-concentration detection of mercuric ions in aqueous solutions. The sensor selectively detects mercury in the presence of sodium, calcium, magnesium, and iron ions. A strong binding was observed between the mercuric ions and the substrate at a pH range of 6.5–7.5, which makes the substrate a distinctive luminescence sensor for detecting mercury at ambient conditions. The sensor shows a linear response towards Hg2+in the concentration range 5.0 × 10-5to 2.5 × 10-8M with a limit of detection of 5.0 × 10-8M. The sensor can also detect zinc ions at a pH of 10 or higher. The results indicate that this sensor has a promising future for the detection of mercury in real environmental water samples. [ABSTRACT FROM AUTHOR]

A review of some papers published in the last fifty years that focus on the semiconducting metal oxide (SMO) based sensors for the selective and sensitive detection of various environmental pollutants is presented. [ABSTRACT FROM AUTHOR]

Background: Hepatitis C virus (HCV) is a major cause of chronic liver disease worldwide. The role of intra familial HCV transmission is still controversial. The aim of the present study is to determine intra familial transmission (sexual and non sexual contacts) of HCV in a group of Iranian population. Patients and methods: In this historical cohort study, 270 first degree relatives of hepatitis C patients were enrolled as the exposed group and compared to 270 first degree relatives of normal subjects (with negative HCV) as the unexposed group. Antibodies to HCV were detected by commercially available fourth-generation enzyme immunoassay. Positive serum specimens were retested using a second generation recombinant immunoblot assay. Fisher's exact test was used to detect association between the exposure and out come of the study. Results: The mean age of exposed group was 27.1±19.8 years and 38.1% were male. The mean age of unexposed group was 29.4±16.7 years and 51.9% were male. Regarding gender, age, familial relation and condom use, there were not statistically significant differences between exposed and unexposed subjects. Only 2 HCV-infected subjects were detected in the unexposed group, both of whom were intravenous drug users. The frequency of positive HCV antibody among household contacts of two groups was not significantly different (NS). Conclusion: Our results revealed that house hold contact transmission of HCV is not a significant transmission route and sexual transmission does not seem to play a role in the intra familial spread of HCV infection. [ABSTRACT FROM AUTHOR]

Reactions of 3,6-bis(2'-pyridyl)pyridazine derivatives (n-dppn)¶ with MX2(PhCN)2 (M = Pd, Pt; X = Cl, Br) have been investigated. The new complexes cis-[PdCl2(n-dppn)] (n = 5, 6, 8, 12), cis-[PtCl2(n-dppn)] · H2O (n = 5, 6), cis-[PtCl2(8-dppn)] and cis-[PtBr2(5-dppn)] have been characterized by elemental analyses, conductivity measurements, infrared, electronic and 1H-NMR spectra. [ABSTRACT FROM AUTHOR]

Ag(I) nanoclusters doped in X and mordenite zeolites were prepared and analyzed using spectroscopy. Both experimental and theoretical studies of the prepared compounds show the presence of silver nanoclusters with various sizes and environments. The presence of Ag(I) nanoclusters doped in X and mordenite zeolites with high silver loadings enhanced the photodecomposition rate of carbofuran 215- and 184-fold, respectively, while the photodecomposition of carbaryl in the presence of these catalysts show room temperature rate constants that are 182- and 168-times faster than the photodecomposition of carbaryl in the absence of the silver-doped zeolite catalysts. The reaction rates were found to be dependent on the amount of silver loaded into the zeolite. [ABSTRACT FROM AUTHOR]

The photodecomposition of dimethyl methylphosphonate (DMMP) and trimethyl phosphate (TMP) adsorbed on monoclinic WO3 powders when irradiated by ultraviolet light (UV) in air, oxygen, and under evacuation was investigated using infrared spectroscopy (IR). The IR spectra show that DMMP decomposes into methyl phosphonate upon exposure to 254 nm UV for 2 h at room temperature in air. The same decomposition of DMMP occurs only at temperatures above 300°C without UV illumination. TMP differs from DMMP in that the photodecomposition product is not the same as the decomposition product obtained by heating above 300°C. Thermal decomposition leads to formation of a phosphate on the surface, whereas photodecomposition leads to the same adsorbed methyl phosphonate as found for the thermal or photodecomposition of DMMP. Since TMP does not contain a P–CH3 bond, the formation of a methyl phosphonate on the surface after UV illumination involves a mechanism where CH3 groups migrate from the methoxy group to the phosphorous central atom. No decomposition is observed at room temperature when DMMP or TMP adsorbed on WO3 is irradiated under vacuum or in nitrogen atmosphere. Therefore, the photodecomposition of either DMMP or TMP adsorbed on WO3 at room temperature does not involve a reaction with the lattice oxygen but rather a reaction with the oxygen radicals produced by the decomposition of ozone. [ABSTRACT FROM AUTHOR]

Silver-doped Y-type zeolites with different silver loadings were prepared and analyzed spectroscopically at various temperattires. Several emission bands were observed for each AgY sample. Each emission band becomes dominant over the others by selecting a suitable excitation wavelength, indicating the presence of different silver clusters in zeolite Y. The study shows that the presence of AgY catalysts increases the photodecomposition rate of carbaryl by 4-42 times in comparison to the catalyst-free system, with the rate dependent on the amount of silver that was loaded on the Y-type zeolites. The presence of different concentrations of Suwannee River natural organic matter (NOM) affected the photodegradation reaction of carbaryl by allowing it to proceed via two different pseudo-first-order pathways. However, the presence of the silver-doped zeolite catalysts makes the photodecomposition of carbaryl proceed via first-order kinetics. [ABSTRACT FROM AUTHOR]

Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 g N m(-2) preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 g N m(-2). No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE), nitrogen recovery efficiency (NRE), N uptake, and rice yield when legume crops were grown in rotation with rice. Rice after winged bean grown with N at the rate of 4 g N m(-2) achieved significantly higher NRE, NAE, and N uptake in both years. Rice after winged bean grown without N fertilizer produced 13-23% higher grain yield than rice after fallow rotation with 8 g N m(-2). The results revealed that rice after winged bean without fertilizer and rice after long bean with N fertilizer at the rate of 4 g N m(-2) can produce rice yield equivalent to that of rice after fallow with N fertilizer at rates of 8 g N m(-2). The NAE, NRE, and harvest index values for rice after winged bean or other legume crop rotation indicated a positive response for rice production without deteriorating soil fertility. [ABSTRACT FROM AUTHOR]