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Advanced glycation end products (AGEs) are known to play a leading part in the pathogenesis of human diseases, such as diabetes, Alzheimer's disease, lateral sclerosis, and atherosclerosis. It is for this reason that research on AGEs is crucial and large-scale studies are needed for the treatment of diseases. The aim of this study was to develop a reproducible method to analyze Amadori compounds using an automated enrichment protocol for high-throughput analysis of clinical samples. The developed method enabled the enrichment of Amadori compounds simultaneously from 96 samples, and it was applied to the discovery of biomarkers in AGEs related diseases. In this study, ten human serum samples were processed using automated filter-aided sample preparation (aFASP) in a 96-well filter plate, and the eluted peptide mixtures were enriched by Affinity Cellufine PB in a fritted 96-well filter plate using a liquid handling robotic system. The eluted glycated peptides were analyzed by a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system. A total of 982 unique glycated peptides, corresponding to 524 unique glycated proteins, were identified from the analysis of ten human samples. The advantages and potentials of the automated sample preparation system were demonstrated through label free quantification of the glycated peptides. [ABSTRACT FROM AUTHOR]

Apoptosis is one of the fundamental phenomena behind successful radiation and chemotherapy treatments. Non-invasive imaging of apoptosis can offer an early diagnosis of disease and the true efficiency of an ongoing treatment procedure. The present study describes an attempt to develop Tc-labeled 2-methyl-2-pentylmalonic acid ([Tc] 8) as a new SPECT based apoptosis imaging agent. An optimized chemical and radiosynthesis procedure provided desired product [Tc] 8 with high radiochemical yield (84%, n = 3) and radiochemical purity (>99%) as determined by radio HPLC. Biodistribution data indicated that the radiotracer has a rapid clearance from blood and other background tissues. High testes accumulation confirmed the ability of the radiotracer to detect testicular apoptosis in mice. [ABSTRACT FROM AUTHOR]

A variety of radioiodination methods is available in the literature depending upon the nature of organic compound to be labeled, however only few can completely fulfill manufacturing requirements.Ideally a selected method should be one which offers maximum benefits like regioselectivity, minimum reaction steps, minimum reaction time, high radiochemical yield and high specific activity. In this review radioiodination techniques were critically analyzed. Advantages, drawbacks, possible mode of action and special reaction conditions required to get high radiochemical yield were taken into account. The influence of iodine introduction on physicochemical properties, in vivo or in vitro pharmacological properties of pharmaceutical due to increase of lipophilicity were discussed along with examples. [ABSTRACT FROM AUTHOR]

The aim of this study is to synthesize I-labeled 2-(4-iodophenethyl)-2-methylmalonic acid ([I]IMA) for the development of new apoptosis imaging tracer. The optimized radiolabeling procedure provided [I]IMA with high radiochemical yield (75.5 ± 5.2 %) and radiochemical purity (>99 %) within 100 min. Specific radioactivity of [I]IMA was 31.0 MBq/μmol. Biodistribution study of [I]IMA was carried out using ICR mouse and the result showed the uptake values in apoptotic cells of the testes of the male mice were 1.7-3.2 fold higher than those of leg muscle. Therefore, [I]IMA will be a promising radiotracer for in vivo SPECT imaging of apoptotic cells. [ABSTRACT FROM AUTHOR]

The purpose of this study is to synthesize I-labeled hesperetin and to investigate its in vivo behavior. The optimized labeling condition provided two isomers of I-labeled hesperetin with high radiochemical yields and radiochemical purities. Both I-labeled products were orally administered to normal ICR mice, and the initial result showed that most of I activity was detected in the stomach and the intestines. A part of I-labeled hesperetin was absorbed from the small intestine to bloodstream and then it was distributed in normal organs. The results in the present study provided an efficient radiolabeling method of flavonoid and quantitative organ distribution of orally administered hesperetin. [ABSTRACT FROM AUTHOR]

Herein we report an efficient method for iodine radioisotope labeling of cyclooctyne-containing molecules using copper-free click reaction. For this study, radioiodination using the tin precursor 2 was carried out at room temperature to give 125 I-labeled azide ([ 125 I] 1 ) with high radiochemical yield (85%) and excellent radiochemical purity. Dibenzocyclooctyne (DBCO) containing cRGD peptide and gold nanoparticle were labeled with [ 125 I] 1 at 37 °C for 30 min to give triazoles with good radiochemical yields (67–95%). We next carried out tissue biodistribution study of [ 125 I] 1 in normal ICR mice to investigate the level of organ accumulation which needs to be considered for pre-targeted in vivo imaging. Large amount of [ 125 I] 1 distributed rapidly in liver and kidney from bloodstream and underwent rapid renal and hepatobiliary clearance. Moreover [ 125 I] 1 was found to be highly stable (>92%) in mouse serum for 24 h. Therefore [ 125 I] 1 could be used as a potentially useful radiotracer for pre-targeted imaging. Those results clearly indicated that the present radiolabeling method using copper free click reaction would be quite useful for both in vitro and in vivo labeling of DBCO group containing molecules with iodine radioisotopes. [ABSTRACT FROM AUTHOR]

Drug Design: An 18F‐labeled caspase‐3‐sensitive nanoaggregation positron emission tomography tracer was prepared and evaluated for imaging the caspase‐3 activity in doxorubicin‐treated tumor xenografts. Enhanced retention of the 18F activity in apoptotic tumors is achieved through intramolecular macrocyclization and in situ aggregation upon caspase‐3 activation (see picture). [ABSTRACT FROM AUTHOR]

Wirkstoff ‐ Design: Ein 18F ‐ markiertes Nanoaggregat ‐ bildendes Capase ‐ 3 ‐ empfindliches Radiopharmakum für die Positronenemissionstomographie wurde hergestellt und die Abbildung der Caspase ‐ 3 ‐ Aktivität in Doxorubizin ‐ behandelten Tumorxenotransplantaten bewertet. Eine verstärkte Retention der 18F ‐ Aktivität in apoptotischen Tumoren wird durch intramolekulare Makrocyclisierung und In ‐ situ ‐ Aggregation nach der Caspase ‐ 3 ‐ Aktivierung erhalten (siehe Bild). [ABSTRACT FROM AUTHOR]

Abstract: An efficient and stereoselective synthesis of d-iminolyxitol, a potent α-galactosidase inhibitor, is achieved in 11 steps over 45% overall yield from N-Boc-O-Bn-d-serine. The key step involves the OsO4-catalyzed syn-selective dihydroxylation reaction of the acyclic γ-amino-α,β-unsaturated (Z)-ester controlled by an N-diphenylmethylene group. [Copyright &y& Elsevier]

Abstract: Protection of 1,2-dialkyl substituted (Z)-allylic amines with an N,N-diBoc group resulted in an opposite stereoselectivity in the OsO4-catalyzed dihydroxylation reactions to that of N-Boc-(Z)-allylic amines. A higher anti selectivity (>10:1) was shown in CH2Cl2. An efficient stereoselective synthesis of a tetraacetyl derivative of d-ribo-phytosphingosine was reported using the N,N-diBoc-controlled dihydroxylation from Garner’s aldehyde. [Copyright &y& Elsevier]

In the last two decades, various nanomaterials have attracted increasing attention in medical science owing to their unique physical and chemical characteristics. Incorporating radionuclides into conventionally used nanomaterials can confer useful additional properties compared to the original material. Therefore, various radionuclides have been used to synthesize functional nanomaterials for biomedical applications. In particular, several α- or β-emitter-labeled organic and inorganic nanoparticles have been extensively investigated for efficient and targeted cancer treatment. This article reviews recent progress in cancer therapy using radiolabeled nanomaterials including inorganic, polymeric, and carbon-based materials and liposomes. We first provide an overview of radiolabeling methods for preparing anticancer agents that have been investigated recently in preclinical studies. Next, we discuss the therapeutic applications and effectiveness of α- or β-emitter-incorporated nanomaterials in animal models and the emerging possibilities of these nanomaterials in cancer therapy. [ABSTRACT FROM AUTHOR]

In this study, we reviewed smog chamber systems and methodologies used in secondary organic aerosol (SOA) formation studies. Many important chambers across the world have been reviewed, including 18 American, 24 European, and 8 Asian chambers. The characteristics of the chambers (location, reactor size, wall materials, and light sources), measurement systems (popular equipment and working principles), and methodologies (SOA yield calculation and wall-loss correction) are summarized. This review discussed key experimental parameters such as surface-to-volume ratio (S/V), temperature, relative humidity, light intensity, and wall effect that influence the results of the experiment, and how the methodologies have evolved for more accurate simulation of atmospheric processes. In addition, this review identifies the sources of uncertainties in finding SOA yields that are originated from experimental systems and methodologies used in previous studies. The intensity of the installed artificial lights (photolysis rate of NO2 varied from 0.1/min to 0.40/min), SOA density assumption (varied from 1 g/cm3 to 1.45 g/cm3), wall-loss management, and background contaminants were identified as important sources of uncertainty. The methodologies developed in previous studies to minimize those uncertainties are also discussed. [ABSTRACT FROM AUTHOR]

Toxic fission products, such as cesium (137Cs) and iodine (129I) are of great concern because of their long half-lives and high solubility in water. The simultaneous removal of Cs and I using a single adsorbent is an area of increasing interest. In this study, MXene/silver nanowire (AgNW) composite was synthesized through physical mixing and employed for simultaneous removal of iodide (I−) and cesium (Cs+) ions from contaminated water. The MXene/AgNW composite demonstrated excellent adsorption capacities of 84.70 and 26.22 mg/g for I− and Cs+, respectively. The experimental data supported the hypothesis of multilayer adsorption of Cs+ owing to the inter-lamellar structures and the presence of heterogeneous adsorption sites in MXene. The interaction between I− and the AgNW involved chemisorption followed by monolayer adsorption. MXene/AgNW composite material exhibited promising results in the presence of competitive ions under extreme pH conditions. Thus, synthesized composite materials holds promising potential as an adsorbent for the remediation of radioactive liquid waste. [ABSTRACT FROM AUTHOR]

Graphical abstract Novel Cu(II), Zn(II) and Cd(II) complexes supported by N -methyl- N -((pyridine-2-yl)methyl)benzeneamine (npmb) have been synthesized and characterized by X-ray diffraction. [(npmb)ZnCl 2 ] exhibited the higher catalytic activity for MMA polymerization in the presence of modified methylaluminoxane (MMAO) at 60 °C and resulted syndio-enriched poly(methylmethacrylate) (PMMA) compared to its Cu(II) and Cd(II) analogues. Highlights • Cu(II), Zn(II) and Cd(II) complexes with N -methyl- N -((pyridine-2-yl)methyl)benzeneamine. • Dimeric Cu(II) and Cd(II) complexes showed distorted trigonal bipyramidal geometries. • Monomeric Zn(II) complex adopted a distorted tetrahedral geometry around the Zn centre. • [(npmb)ZnCl 2 ] yielded high molecular weight (11.1 g/mol × 105) syndio-enriched PMMA. • Higher activities were observed for Zn(II) initiators compared to Cu(II) and Cd(II) analogous. Abstract Copper(II), cadmium(II) and zinc(II) complexes containing N -methyl- N -((pyridine-2-yl)methyl)benzeneamine (npmb) ligand have been synthesized and characterized by X-ray crystallography. Molecular structures of Cu(II) and Cd(II) complexes revealed dimeric structures with square pyramidal and distorted trigonal bipyramidal geometries, respectively, involving two nitrogen atoms, two bridged and one terminal halogen ligands. However, the monomeric Zn(II) complex showed a distorted tetrahedral geometry around the Zn centre. [(npmb)ZnCl 2 ] exhibited the higher catalytic activity (2.88 × 104 g PMMA/molZn·h) for the polymerization of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO) at 60 °C and yielded high molecular weight (11.1 g/mol × 105) syndiotactic-enriched poly(methylmethacrylate) (PMMA) compared to its Cu(II) and Cd(II) analogues. [ABSTRACT FROM AUTHOR]

In GMAW (gas metal arc welding) of Zn (zinc)-coated steel sheets, defects such as pores occur in the weld due to trapped Zn vapor. To solve this problem, we investigated the pore-free welding condition using conventional solid wire. We verified through experiments that the combination of 20% CO2-Ar shielding gas and DCEP (direct current electrode positive) polarity has a higher pore-free performance than other combinations. A higher performance of pore-free welding was obtained by reducing the CTWD (contact tip to work distance) and using ER70S-3 wire. In conclusion, the optimized welding conditions at 10 mm overlap, 80 cm/min welding speed, and 30° work angle are 160 A arc current, 20 V voltage, 15 mm CTWD, 10° push angle, DCEP polarity, 20% CO2-Ar shielding gas with 20 L/min flow rate, and ER70S-3 wire type. For flow pattern analysis, a high-speed camera with blue laser was used, and it was observed that a longer weld pool and smaller droplets could improve the efficiency of Zn vapor emission. With ER70S-3, a longer weld pool can be obtained, as it has a lower viscosity due to lower percentages of Si and Mn in its composition. [ABSTRACT FROM AUTHOR]

The caspase‐3 activity in doxorubicin‐treated tumor xenografts is studied by positron emission tomography (PET) using a novel 18F‐labeled caspase‐3‐sensitive nanoaggregation tracer. In their Communication on page 10511 ff., J. Rao, F. T. Chin, et al. show that the enzyme‐activatable tracer improves the PET imaging of apoptotic tumors by intramolecular macrocyclization and in situ aggregation of the cyclized tracer upon caspase‐3 activation. (Picture: Jim Strommer and Lydia‐Marie Joubert.) [ABSTRACT FROM AUTHOR]

Die Caspase ‐ 3 ‐ Aktivität in mit Doxorubicin behandelten Tumorxenotransplantaten wird unter Verwendung eines 18F ‐ markierten, für Caspase ‐ 3 empfindlichen Nanoaggregat ‐ bildenden Tracers mit Positronenemissionstomographie (PET) untersucht. In der Zuschrift auf S. 10705 ff. zeigen J. Rao, F. T. Chin et al., dass der Enzym ‐ aktivierbare Tracer durch intramolekulare Makrocyclisierung und In ‐ situ ‐ Aggregatbildung des cyclisierten Tracers nach Caspase ‐ 3 ‐ Aktivierung verfeinerte PET ‐ Bilder von apoptotischen Tumoren liefert. Bild: Jim Strommer und Lydia ‐ Marie Joubert. [ABSTRACT FROM AUTHOR]

N,N -bis((1H-pyrazol-1-yl)methyl)(cyclohexyl)methanamine ( L A ), N,N -bis((1H-pyrazol-1-yl)methyl)-2,6-diethylbenzenamine ( L B ), N,N -bis((1H-pyrazol-1-yl)methyl)-4-bromobenzenamine ( L C ), N,N -bis((1H-pyrazol-1-yl)methyl)cyclohexanamine ( L D ), N,N -bis((1H-pyrazol-1-yl)methyl)(furan-2-yl)methanamine ( L E ), N , N -bis((1H-pyrazol-1-yl)methyl)-2-methoxyethanamine ( L F ), and N , N -bis((1H-pyrazol-1-yl)methyl)-3-(methylthio)propan-1-amine ( L G ) with [CoCl 2 ·6H 2 O] in ethanol yield a novel series of Co(II) chloride complexes; i.e. [L n CoCl 2 ] ( L n = L A – L G ), respectively. The molecular structures of [L n CoCl 2 ] ( L n = L A – L C ) and [L n CoCl 2 ] ( L n = L D – L G ) exist as monomeric four-coordinated and five-coordinated complexes, respectively. [L n CoCl 2 ] ( L n = L A – L C ) showed a distorted tetrahedral geometry involving non-coordination of the nitrogen atom of the N′ -substitution amine moiety and the Co(II) centre, resulting in the formation of an eight-membered chelate ring. The geometry at each Co(II) centre in [L n CoCl 2 ] ( L n = L D – L G ) were best described as a distorted trigonal bipyramid involving coordination of the nitrogen atom of the N′ -substitution amine group and the Co(II) centre. Specifically, a distorted trigonal bipyramid was achieved in [L D CoCl 2 ] through a coordinative interaction of the nitrogen atom of the cyclohexylamine unit and the Co(II) atom with an σ plane of symmetry based on the bond length of Co–N cyclcohexylamine [2.466(4) Å]. Moreover, [L D CoCl 2 ] showed the highest activity for methyl methacrylate (MMA) polymerization in the presence of modified methylaluminoxane (MMAO) at 60 °C and yielded poly(methylmethacrylate) (PMMA) with a high molecular weight ( M w ) and narrower polydispersity index (PDI) compared to the other Co(II) complexes. However, all Co(II) complexes produced syndiotactic (PMMA), characterised using 1 H NMR spectroscopy, with ca. 0.70. [ABSTRACT FROM AUTHOR]

The aim of this study was to synthesize hyaluronic acid-tyramine (HA-Tm) conjugate and label it with radioisotopes for in vivo biodistribution study. Radiolabeling of HA-Tm was carried out using I and I and the observed radiochemical yield were 96 and 98 % respectively. Biodistribution study of radiolabeled HA-Tm was performed with normal Balb/c mice via oral administration. The uptake values of [I]HA-Tm in organs were measured by gamma-counter at different time points. Biodistribution results showed that most radioactivities were observed in the gastrointestinal tract at initial time point. A small part of [I]HA-Tm was then absorbed into the bloodstream from the small intestine and distributed in some organs. SPECT/CT images of orally administered [I]HA-Tm were well matched with the biodistribution data. The results in the present study would provide an efficient radiolabeling method of hyaluronic acid and also present quantitative organ distributions of orally administered HA. [ABSTRACT FROM AUTHOR]

The reaction of [CdBr 2 . 4H 2 O] with N′ -substituted N , N -di(2-picolyl)amine ligands such as 1-cyclohexyl- N , N -bis(pyridin-2-ylmethyl)methanamine ( L A ), N , N -bis(pyridin-2-ylmethyl)aniline ( L B ), 2-methoxy- N , N -bis(pyridin-2-ylmethyl)ethan-1-amine ( L C ) and 3-methoxy- N , N -bis(pyridin-2-ylmethyl)propan-1-amine ( L D ) in ethanol yielded cadmium(II) [Cd(II)] complexes, i.e. [L n CdBr 2 ] m (L n = L A , m = 2; L B , m = 1; L C , m = 1; L D , m = 2, respectively). The molecular structures of Cd(II) complexes revealed that 6-coordinate dimeric [L A Cd(μ−Br)Br] 2 and [L D Cd(μ−Br)Br] 2 showed a distorted octahedral geometry through coordination of nitrogen in the N′ -substituted amine moiety (cyclohexylmethylamine and 3-methoxypropylamine, respectively) to the Cd metal centre and a bromide bridge ligand. However, the 5-coordinate monomeric [L B CdBr 2 ] was square pyramidal through the coordination of nitrogen in the N′ -phenyl-substituted amine residue to the Cd metal centre. The molecular structure of 6-coordinate monomeric [L C CdBr 2 ] had a distorted octahedral geometry achieved through bidentate coordination of nitrogen and oxygen in the N′ -methoxyethylamine group to the Cd metal centre. However, for dimeric [L D Cd(μ−Br)Br] 2 , although L D has a bidentate coordination ability in the N′ -methoxypropylamine group, it generated a distorted octahedral geometry through coordination of nitrogen and non-coordination of oxygen in the N′ -methoxyethylamine moiety to the Cd metal centre. Monomeric complex [L B CdBr 2 ] [6.70 × 10 4 gPMMA·(molCd·h) −1 ] showed higher catalytic activity for the polymerisation of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO) than the rest of Cd(II) complexes in this study. The catalytic activity of dimeric complex [L A Cd(μ−Br)Br] 2 [7.00 × 10 4 gPMMA·(molCd·h) −1 ] and [L D Cd(μ−Br)Br] 2 [7.07 × 10 4 gPMMA·(molCd·h) −1 ] increased by twofold due to the presence of two Cd metal centres compared to the corresponding reference complex [CdBr 2 . 4H 2 O] [2.85 × 10 4 gPMMA·(molCd·h) −1 ] or anhydrous [CdCl 2 ] [3.53 × 10 4 gPMMA·(molCd·h) −1 ]. All Cd(II) complexes resulted in syndiotactic poly(methylmethacrylate) (PMMA) with ca. 0.70. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pantoea sp. PL-1 inhibits biofilm in AI-2 QS strains, hindering DPD concentration. • PL-1 degrades DPD more efficiently (15 times) than Acinetobacter sp. DKY-1. • Applying PL-1 in an MBR showed 40% more biofilm reduction than DKY-1. • PL-1 alters microbial communities, potentially suppressing EPS production genes. • Hydrophilic, low molecule of PL-1′s AI-2 QQ substance needs crucial exploration. Prior investigations concerning quorum quenching (QQ), which hinders quorum sensing (QS) in microbial communication, concentrated predominantly on N -acylhomoserine lactones (AHLs), which are communicated merely by gram-negative bacteria. However, to combat biofouling more effectively, particularly biofilm-related issues, it is important to explore the inhibition of autoinducer-2 (AI-2), a universal signal (interspecies communication) employed by both gram-negative and gram-positive bacteria. This study aimed to isolate and identify novel strains capable of more effectively inhibiting AI-2 signaling for use in engineering fields. The results revealed that the newly isolated strain Pantoea sp. PL-1 demonstrated remarkable efficacy in attenuating AI-2 signals, leading to a substantial reduction in the AI-2 precursor (S)-4,5-dihydroxy-2,3-pentandione (DPD) in both its pellet (with a DPD removal efficiency of 90.8 % after 180 min, with a rate constant of k = 0.8 h−1) and supernatant form (66.9 %, k = 0.37 h−1). Interestingly, the findings indicate that strain DKY-1, a strain previously reported to exhibit AI-2 QQ activity, only reduced DPD levels in its supernatant form (extracellular activity), while both the pellet and the supernatant of strain PL-1 demonstrated AI-2 QQ activity, indicating both intracellular and extracellular QQ activity. Adding the PL-1 supernatant to co-cultures of two AI-2 QS strains, E. coli K12 and P. mirabilis , successfully reduced DPD by 40 % and 70 %, respectively, without impeding their growth. Additionally, when assessing the impact of PL-1 to minimize membrane biofouling in a membrane bioreactor, it demonstrated superior performance compared to the DKY-1 strain, with a 40 % improvement. The AI-2 QQ compound of PL-1 has been identified as highly hydrophilic and low-molecular-weight, and its exact properties have not yet been fully elucidated. Therefore, uncovering its identity may be an important goal for future research. [ABSTRACT FROM AUTHOR]

Abstract: This study provides experimental evidence for proton and hydrogen formation caused by the anodic electropolymerization of cyclohexyl benzene (CHB), which is a popular electrolyte additive for overcharge protection of lithium-ion batteries (LIBs). It is found that considerable H2 evolution is observed in overcharged LiCoO2/graphite cells, especially when CHB is included as an electrolyte additive. In order to confirm the proton generation during the CHB oxidation, Pt/Pt-rotating ring disc electrode (RRDE) measurements are performed in 1M Li(C2F5SO2)2N ethylene carbonate/ethyl methyl carbonate (1/2, v/v) solutions with and without CHB. The cathodic ring current is intimately correlated to the anodic disc current, and the cathodic reaction at the ring is determined to be the reduction of the proton. The proton generation efficiency during the CHB oxidation is as high as 90%. Proton liberation is also observed during the anodic decomposition of the electrolyte solvents, although it occurs in a much less stoichiometric way compared with that during the CHB oxidation. [Copyright &y& Elsevier]

In recent years, several catalyst-free site-specific reactions have been investigated for the efficient conjugation of biomolecules, nanomaterials, and living cells. Representative functional group pairs for these reactions include the following: (1) azide and cyclooctyne for strain-promoted cycloaddition reaction, (2) tetrazine and trans-alkene for inverse-electron-demand-Diels–Alder reaction, and (3) electrophilic heterocycles and cysteine for rapid condensation/addition reaction. Due to their excellent specificities and high reaction rates, these conjugation methods have been utilized for the labeling of radioisotopes (e.g., radiohalogens, radiometals) to various target molecules. The radiolabeled products prepared by these methods have been applied to preclinical research, such as in vivo molecular imaging, pharmacokinetic studies, and radiation therapy of cancer cells. In this review, we explain the basics of these chemical reactions and introduce their recent applications in the field of radiopharmacy and chemical biology. In addition, we discuss the significance, current challenges, and prospects of using bioorthogonal conjugation reactions. [ABSTRACT FROM AUTHOR]

Benzylalkyldimethylammonium chloride (BAC), a quaternary ammonium compound (QAC), is utilized in industrial and biomedical applications for antimicrobial purposes. Since the coronavirus disease (COVID-19) outbreak, various types of BAC-containing household chemicals have been produced. BACs have several adverse effects; however, their biological uptake, translocation, and excretion in animal models (essential for better understanding in vivo behavior and toxicological impact) remain unclear. In this study, we performed the first biodistribution and whole-body imaging studies of BAC in male Sprague Dawley rats, using two different administration routes. Quantitative whole-body autoradiography (QWBA) data obtained for intranasal 14C-labeled BAC ([14C]C12-BAC) exposure showed substantial uptake values for the respiratory organs (e.g. 346 ng g−1 of lung at 3 h post administration) and the radiotracer was transported to other internal organs. The amount of radiotracer in the heart, adrenal gland, and pancreas were 198, 1410, and 186 ng g−1 tissue respectively at 168 h following exposure. Autoradiograms obtained after intravenous injection also showed high accumulation and slow excretion in these organs. The cumulative excretion analysis revealed that approximately 6.4% of the administered radioactivity remained in rats after a week. The results indicated that continuous inhalation exposure to BAC leads to potential toxic effects in extrapulmonary organs and the respiratory tract. Thus, the radiolabeling method utilized may help assess various synthetic QACs in living subjects. [Display omitted] • The radiolabeled benzylalkyldimethylammonium chloride (BAC) was synthesized. • Biological uptake and in vivo behavior of BAC were assessed using the radiotracer. • 14C-labeled BAC was administered in rats via the intranasal and intravenous routes. • After the inhalation exposure, BAC was translocated to extrapulmonary organs. • Significant accumulations were observed in the heart, adrenal gland, and pancreas. [ABSTRACT FROM AUTHOR]

As a robust radioanalytical method for tracking carbonaceous particulates in vivo, polycyclic aromatic hydrocarbons from diesel exhaust were labeled with a radioactive-iodine-tagged pyrene analogue. Single-photon emission computed tomography and biodistribution studies showed high uptake and slow clearance of this matter in the respiratory system, which may underlie its severe toxicity. [ABSTRACT FROM AUTHOR]

In this report, we describe the radiosynthesis of a new thiol-targeting prosthetic group for efficient radioactive iodine labeling of biomolecules. Radioiodination using the precursor 3 was performed to obtain 125 I-labeled tetrazole 4b with high radiochemical yield (73%) and radiochemical purity. Using the radiolabeled 4b , a single free cysteine containing peptide and human serum albumin were labeled with 125 I in modest-to-good radiochemical yields (65–99%) under mildly reactive conditions. A biodistribution study of [ 125 I] 7 in normal ICR mice exhibited lower thyroid uptake values than those of 125 I-labeled human serum albumin prepared via a traditional radiolabeling method. Thus, [ 125 I] 7 could be employed as an effective radiotracer for molecular imaging and biodistribution studies. The results clearly demonstrate that 4b has the potential to be effectively implemented as a prosthetic group in the preparation of radiolabeled biomolecules. [ABSTRACT FROM AUTHOR]

To assess the risk posed by a toxic chemical to human health, it is essential to quantify its uptake in a living subject. This study aims to investigate the biological distribution of inhaled polyhexamethylene guanidine (PHMG) aerosol particle, which is known to cause severe pulmonary damage. By labeling with indium-111 ( 111 In), we quantified the uptake of PHMG for up to 7 days after inhalation exposure in rats. The data demonstrate that PHMG is only slowly cleared, with approximately 74% of inhaled particles persisting in the lungs after 168 h. Approximately 5.3% of inhaled particles were also translocated to the liver after 168 h, although the level of redistribution to other tissues, including the kidneys and spleen, was minimal. These observations suggest that large uptake and slow clearance may underlie the fatal inhalation toxicity of PHMG in humans. [ABSTRACT FROM AUTHOR]

We herein report a convenient radiolabeling method capable of real-time in vivo imaging and biodistribution of bacteria in a living subject. Escherichia coli (E. coli), a model microorganism in this study, was incubated with technetium-99m (99mTc) tricarbonyl under physiological conditions provided radiolabeled bacterial cells. 99mTc-labeled bacterial cells were obtained in high yield (42%, n = 5) and purity (> 99%) within 30 min. In vitro radiolabeling study using cellular components revealed that 99mTc could be incorporated with cytosolic proteins and it was maintained stably in E. coli under several media including mouse serum, high salt solutions with varying pH. SPECT/CT images and organ biodistribution of 99mTc-labeled bacterial cells showed quantitative in vivo behavior and accumulation of E. coli in mice. The radiolabeling method demonstrated here will be a promising platform tool for in vivo tracking and biodistribution of infectious microorganism. [ABSTRACT FROM AUTHOR]

Exposure to diesel particulate matter (DPM) is associated with several adverse health effects, including severe respiratory diseases. Quantitative analysis of DPM in vivo can provide important information on the behavior of harmful chemicals, as well as their toxicological impacts in living subjects. This study presents whole-body images and tissue distributions of DPM in animal models, using molecular imaging and radiolabeling techniques. The self-assembly of the 89Zr-labeled pyrene analog with a suspension of DPM efficiently produced 89Zr-incorporated DPM (89Zr-DPM). Positron emission tomography images were obtained for mice exposed to 89Zr-DPM via three administration routes: intratracheal, oral, and intravenous injection. DPM was largely distributed in the lungs and only slowly cleared after 7 days in mice exposed via the intratracheal route. In addition, a portion of 89Zr-DPM was translocated to other organs, such as the heart, spleen, and liver. Uptake values in these organs were also noticeable following exposure via the intravenous route. In contrast, most of the orally administered DPM was excreted quickly within a day. These results suggest that continuous inhalation exposure to DPM causes serious lung damage and may cause toxic effects in the extrapulmonary organs. [Display omitted] • A89Zr-labeling method was used for tracing diesel particulate matter (DPM) in mice. • 89Zr-incorporated DPM was administered in mice via three different routes. • When exposed via the intratracheal route, DPM was highly distributed in the lungs and excreted slowly. • Uptake in some organs such as spleen and heart were evident following intravenous exposure. • Most of the orally administered diesel particulates were cleared quickly in a day. [ABSTRACT FROM AUTHOR]

We herein report a new bioremediation method using a radiation-resistant bacterium. Biogenic gold nanomaterial-containing Deinococcus radiodurans R1 showed excellent capability for the removal of radioactive iodine (＞99%) in several aqueous solutions. These observations demonstrated that our remediation system would be efficiently applied to the treatment of radioactive wastes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The biodistribution of CMIT/MIT was assessed using a 14C-labeled radiotracer. • After exposure via the inhalation routes, CMIT/MIT is rapidly distributed to the lungs. • Intratracheal exposure induces greater lung damage than intranasal instillation. • The amount of CMIT/MIT in the lungs is positively associated with the toxicity. A variety of isothiazolinone-containing small molecules have been registered and used as chemical additives in many household products. However, their biodistribution and potential harmful effects on human health, especially respiratory effects, were not yet identified in sufficient detail. The purpose of this study was to investigate whether a biocide comprising a mixture of chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) could reach the lungs and induce lung injury when exposure occurs by two administration routes involving the respiratory tract: intratracheal and intranasal instillation. To investigate the biodistribution of CMIT/MIT, we quantified the uptake of 14C-labeled CMIT/MIT in experimental animals for up to seven days after intratracheal and intranasal instillation. In the toxicity study, lung injury was assessed in mice using total inflammatory cell count in bronchoalveolar lavage fluid (BALF) and lung histopathology. The results of the biodistribution study indicated that CMIT/MIT were rapidly distributed throughout the respiratory tract. Using quantitative whole-body autoradiogram analysis, we confirmed that following intranasal exposure, CMIT/MIT reached the lungs via the respiratory tract (nose–trachea–lung). After 5 min post intratracheal and intranasal instillation, the amount of radiotracer ([14C]CMIT/MIT) in the lungs was 2720 ng g−1 and 752 ng g−1 tissue, respectively, and lung damage was observed. A higher amount of the radiotracer resulted in higher toxicity. Both intratracheal and intranasal instillation of CMIT/MIT increased inflammatory cell counts in the BALF and induced injuries in the alveoli. The frequency and the severity scores of injuries caused by intratracheal instillation were approximately-four to five times higher than those induced by intranasal instillation. Therefore, we concluded that CMIT/MIT could reach the lungs following nasal and intratracheal exposure and cause lung injuries, and the extent of injury was dependent on the exposure dose. [ABSTRACT FROM AUTHOR]

In this report, we present a rapid and highly efficient method for radioactive iodine labeling of trans -cyclooctene group conjugated biomolecules using inverse-electron-demand Diels–Alder reaction. Radioiodination reaction of the tetrazine structure was carried out using the stannylated precursor 2 to give 125 I-labeled product ([ 125 I] 1 ) with high radiochemical yield (65 ± 8%) and radiochemical purity (>99%). For radiolabeling application of [ 125 I] 1 , trans -cyclooctene derived cRGD peptide and human serum albumin were prepared. These substrates were reacted with [ 125 I] 1 under mild condition to provide the radiolabeled products [ 125 I] 6 and [ 125 I] 8 , respectively, with excellent radiochemical yields. The biodistribution study of [ 125 I] 8 in normal ICR mice showed significantly lower thyroid uptake values than that of 125 I-labeled human serum albumin prepared by a traditional radiolabeling method. Therefore [ 125 I] 8 will be a useful radiolabeled tracer in various molecular imaging and biological studies. Those results clearly demonstrate that [ 125 I] 1 will be used as a valuable prosthetic group for radiolabeling of biomolecules. [ABSTRACT FROM AUTHOR]

The purpose of the current research is to synthesize radiolabeled rutin for biodistribution study and SPECT/CT image of rutin. The optimized radiolabeling condition provided I-labeled rutin with 53.5 % of radiochemical yield. Most of orally administered I-labeled rutin was initially found in the stomach and small intestine and a portion of the product was then distributed in internal organs. While intravenously injected I-labeled rutin was accumulated in liver and then a large part of it was transferred to small intestine. The present results provided an efficient radiolabeling method of flavonoid glycoside as well as quantitative organ distribution of rutin. [ABSTRACT FROM AUTHOR]

A boronic acid-based fluorescent probe was developed for diagnosis of amyloid-β (Aβ) plaques from Alzheimer’s disease (AD). Probe 4c , which included boronic acid as a functional group, exhibited a significant increase (64.37-fold, F Aβ / F 0 ) in fluorescence intensity as a response to Aβ aggregates, with a blue shift (105 nm) in the maximum emission wavelength. We found that boronic acid as a functional group improved the binding affinity ( K D value = 0.79 ± 0.05 μM for 4c ) for Aβ aggregates and confirmed that 4c selectively stained Aβ plaques in brain sections from APP/PS1 mice. Ex vivo fluorescence imaging using mice (normal and APP/PS1) also revealed that 4c was able to penetrate the blood–brain barrier (BBB) and to stain Aβ plaques in the brain. From these results, we believe that 4c will be useful as a fluorescent probe in preclinical research related to AD. Furthermore, we believe that our results with boronic acid also provide valuable information for the development of a probe for Aβ plaques. [ABSTRACT FROM AUTHOR]

Herein we report the radiosynthesis of a pyridine derived azide prosthetic group for iodine radioisotope labeling of dibenzocyclooctyne (DBCO) conjugated molecules. The radiolabeling of the stannylated precursor 2 was conducted using [ 125 I]NaI and chloramine-T to give 125 I-labeled azide ([ 125 I] 1 ) with high radiochemical yield (72 ± 8%, n = 4) and radiochemical purity (>99%). Using 125 I-labeled azide ([ 125 I] 1 ), cyclic RGD peptide and near infrared fluorescent molecule were efficiently labeled with modest to good radiochemical yields. The biodistribution study and SPECT/CT images showed that [ 125 I] 1 underwent rapid renal clearance. These results clearly demonstrated that [ 125 I] 1 could be used as an useful radiotracer for in vivo pre-targeted imaging as well as efficient in vitro radiolabeling of DBCO containing molecules. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a computational estimation of the total ionizing dose from protons and electrons in the Earth's magnetosphere and interplanetary space for a hypothetical CubeSat transiting from Earth to Mars. An initial hyperbolic escape of the spacecraft from Earth's gravitation is assumed, followed by an elliptical transfer from Earth to Mars under the Sun's gravitation. The rapid traversal of the Earth's radiation belt yields a smaller ionizing dose, whereas high-energy solar protons in the interplanetary space have the greatest effect on the ionizing dose during the transfer between the planets. Variation in the heliocentric distance of the spacecraft is considered in the calculation. Calculation of the shielding distributions with Geant4 and the transport of the ionizing particles across the obtained distributions yields an estimation of the total ionizing dose as a function of position within the spacecraft as well as statistical confidence levels. With a moderate confidence level, this calculation shows that a practical exploration of Mars with a CubeSat is possible in terms of the expected total ionizing dose. [Copyright &y& Elsevier]

Abstract: Propellanes and azapropellanes are attractive compounds for their unique structure and valuable applications but there are few synthetic studies for highly N-substituted azapropellanes. Several novel derivatives of 2,4,6,8,10-pentaaza[3.3.3]propellane, such as 3, 4, and 5 were successfully synthesized from readily available diethyl tartrate. Most of the synthetic steps were efficient. Their propellane structures were established by spectroscopic data and confirmed with single crystal X-ray analyses. [Copyright &y& Elsevier]

Nanotechnology has played a tremendous role in molecular imaging and cancer therapy. Over the last decade, scientists have worked exceptionally to translate nanomedicine into clinical practice. However, although several nanoparticle-based drugs are now clinically available, there is still a vast difference between preclinical products and clinically approved drugs. An efficient translation of preclinical results to clinical settings requires several critical studies, including a detailed, highly sensitive, pharmacokinetics and biodistribution study, and selective and efficient drug delivery to the target organ or tissue. In this context, technetium-99m (99mTc)-based radiolabeling of nanoparticles allows easy, economical, non-invasive, and whole-body in vivo tracking by the sensitive clinical imaging technique single-photon emission computed tomography (SPECT). Hence, a critical analysis of the radiolabeling strategies of potential drug delivery and therapeutic systems used to monitor results and therapeutic outcomes at the preclinical and clinical levels remains indispensable to provide maximum benefit to the patient. This review discusses up-to-date 99mTc radiolabeling strategies of a variety of important inorganic and organic nanoparticles and their application to preclinical imaging studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • New fluorescent probes (8a–d) were designed and synthesized based on a curcumin scaffold. • Probe 8b displayed an emission wavelength in the NIR region and a good binding affinity for the Aβ aggregates. • Probe 8b achieved clear visualization of Aβ plaques in 5XFAD transgenic mice. • The signal intensity of 8b in the brain of the 5XFAD mouse was much higher than that of the control group. • The biological uptake of 8b into the internal organs and brain was confirmed via ex vivo experiments. The abnormal self-assembly of amyloid-beta (Aβ) peptides into oligomers, as well as insoluble fibrils, has been identified as a key factor for monitoring the progression of Alzheimer's disease (AD). The noninvasive imaging of Aβ aggregates utilizing chemical probes can be a powerful and practical technique for accurately diagnosing and monitoring the progress of AD, as well as evaluating the effectiveness of therapeutic drug candidates in treating or managing it. Particularly, the near-infrared (NIR) fluorescence imaging of Aβ plaques is a potentially promising approach toward the efficient detection of the biomarker. In this study, we describe a new NIR fluorophore, which was based on curcumin derivatives. The fluorophore is equipped with desirable optical properties for in vivo brain imaging. The emission wavelength of the probe, 8b , is 667 nm, and its fluorescent intensity is significantly increased through binding with the Aβ aggregates. The probe allows the clear visualization of the Aβ plaques 10 min post administration, and the intensity of the fluorescent signal in the brain of a 5XFAD transgenic mouse model is more than three times higher than that of the normal control group. These results demonstrate that the designed probe can be an effective tool for visualizing Aβ plaques, as well as investigating the pathological progress of AD. [ABSTRACT FROM AUTHOR]

Efficient and cost-effective removal of radioactive iodine (radioiodine) from radioactive contaminated water has become a crucial task, following nuclear power plant disasters. Several materials for removing radioiodine have been reported in the literature. However, most of these materials exhibit some limitations, such as high production cost, slow adsorption kinetics, and poor adsorption capacity. Herein, we present silver/iron oxide nanocomposites (Ag/Fe3O4) for the efficient and specific removal of iodine anions from contaminated water. The Ag/Fe3O4 were synthesized using a modified method and characterized via scanning electron microscopy, transmission electron microscopy, and X-ray diffraction analyses. This adsorbent showed a high adsorption capacity for iodine anions (847 mg/g of the adsorbent) in pure water. Next, Ag/Fe3O4 was applied to the removal of radioiodine, and high removal efficiencies were observed in water. In addition, its desalination capacity was retained in the presence of competitive ions and varied pH. After the adsorption process, Ag/Fe3O4 was easily removed from the water by applying an external magnetic field. Moreover, the same operation can be repeated several times without a significant decrease in the performance of Ag/Fe3O4. Therefore, it is expected that the findings presented in this study will offer a new method for desalinating radioiodine in various aqueous media. [ABSTRACT FROM AUTHOR]

Peroxynitrite (ONOO−), a highly reactive oxygen species generated by the reaction of nitric oxide and superoxide radical anion, is involved in numerous physiological and pathological processes in the human body. To identify important pathogenic mechanisms, it is crucial to develop a reliable tool for detecting peroxynitrite in living systems. In the present study, a new difluoroboron β-diketonate-based fluorescent probe for detecting exogenous and endogenous peroxynitrite in living systems was designed. The red emitting fluorophore can be synthesized in a simple three-step procedure. This probe reacts quickly and selectively with peroxynitrite and its detection limit is determined to be as low as 19.8 nM. It allows for clear imaging of peroxynitrite in RAW 264.7 cells and was successfully applied to visualize changes of intracellular peroxynitrite induced by reactive oxygen species inhibitors. This designed probe is an effective tool for investigating the physiological and pathological role of peroxynitrite in living cells. Image 1 • We synthesized an activatable fluorescence probe to detect intracellular ONOO−. • QPP (1) rapidly and selectively reacts with peroxynitrite over other reactive species. • The activated fluorophore displayed a red emission wavelength in live cells. • A small amount of probe clearly visualized exogenous and endogenous ONOO− in cells. • QPP (1) can be used to study the physiological and pathological roles of ONOO−. [ABSTRACT FROM AUTHOR]

Concern about environmental exposure to hazardous substances has grown over the past several decades, because these substances have adverse effects on human health. Methods used to monitor the biological uptake of hazardous substances and their spatiotemporal behavior in vivo must be accurate and reliable. Recent advances in radiolabeling chemistry and radioanalytical methodologies have facilitated the quantitative analysis of toxic substances, and whole-body imaging can be achieved using nuclear imaging instruments. Herein, we review recent literature on the radioanalytical methods used to study the biological distribution, changes in the uptake and accumulation of hazardous substances, including industrial chemicals, nanomaterials, and microorganisms. We begin with an overview of the radioisotopes used to prepare radiotracers for in vivo experiments. We then summarize the results of molecular imaging studies involving radiolabeled toxins and their quantitative assessment. We conclude the review with perspectives on the use of radioanalytical methods for future environmental research. [ABSTRACT FROM AUTHOR]

Emiliania huxleyi is one of the most abundant marine planktons, and it has a crucial feature in the carbon cycle. However, proteomic analyses of Emiliania huxleyi have not been done extensively. In this study, a three-dimensional liquid chromatography (3D-LC) system consisting of strong cation exchange, high- and low-pH reversed-phase liquid chromatography was established for in-depth proteomic profiling of Emiliania huxleyi. From tryptic proteome digest, 70 fractions were generated and analyzed using liquid chromatography-tandem mass spectrometry. In total, more than 84,000 unique peptides and 10,000 proteins groups were identified with a false discovery rate of ≤0.01. The physicochemical properties of the identified peptides were evaluated. Using ClueGO, approximately 700 gene ontology terms and 15 pathways were defined from the identified protein groups with p-value ≤0.05, covering a wide range of biological processes, cellular components, and molecular functions. Many biological processes associated with CO2 fixation, photosynthesis, biosynthesis, and metabolic process were identified. Various molecular functions relating to protein binding and enzyme activities were also found. The 3D-LC strategy is a powerful approach for comparative proteomic studies on Emiliania huxleyi to reveal changes in its protein level and related mechanism. [ABSTRACT FROM AUTHOR]

Novel Co(II) complexes supported by N,N,N ′ ,N ″-tetradentate N ′-substituted bis((1H-pyrazol-1-yl)methyl)amines) have been synthesized and characterized by X-ray diffraction method. Notably, anion exchange reaction was found to be highly selective; only the substitution of NO 3 − by BPh 4 − was achieved, whereas attempted anion exchange of NO 3 − with BPh 4 − proved unsuccessful. In addition, the presences of methyl substituents at pyrazole moieties play an influential role in determining the anionic exchange capabilities of these complexes. Thus, the counter anion exchange reaction depends on the size and nature of anions but also the geometry of cationic complexes. • Synthesis of Co(II) complexes with bis((1H-pyrazol-1-yl)methyl)amine derivatives. • [L n Co(NO 3)]BPh 4 (L n = L A , L B, L D) showed distorted trigonal bipyramidal geometries. • [L C Co(NO 3)]NO 3 exhibited distorted octahedral geometry around the Co(II) centre. • The substitution of NO 3 − anion by BPh 4 − anion was achieved successfully. A series of cobalt(II) complexes, namely [L n Co(NO 3)]+Y− (L n = L A –L D ; Y = NO 3 −, BPh 4 −) was prepared by the reaction of the corresponding metal starting materials with N , N -bis((1 H -pyrazol-1-yl)methyl)-2-(piperidin-1-yl)ethanamine (L A), N , N -bis((1 H -pyrazol-1-yl)methyl)-2-morpholinoethanamine (L B), N , N -bis((3,5-dimethyl-1 H -pyrazol-1-yl)methyl)-2-(piperidin-1-yl)ethanamine(L C) and N , N -bis((3,5-dimethyl-1 H -pyrazol-1-yl)methyl)-2-morpholinoethanamine (L D), respectively. X-ray diffraction studies revealed that the coordination geometry around the Co(II) centre in [L n Co(NO 3)]BPh 4 (L n = L A , L B and L D) can be best described as distorted trigonal bipyramidal, whereas [L C Co(NO 3)]NO 3 showed a distorted octahedral geometry around the Co(II) centre due to the bidentate binding mode of the ligand NO 3 −. Specifically, the presence of methyl substituents at the pyrazole moieties plays an influential role in determining the anionic exchange capabilities of these complexes. The anion exchange reaction was found to be highly selective; the substitution of the smaller anion NO 3 − to the bigger anion BPh 4 − was achieved easily, whereas the attempted anion exchange of BPh 4 − with NO 3 − proved unsuccessful. [ABSTRACT FROM AUTHOR]

This paper describes a novel chromatographic method for efficient removal of anionic dyes from aqueous solutions. Chitosan-coated Fe3O4 nanoparticles can easily be immobilized on a dextran gel column. Single elution of Evans Blue (EB) solution to the nanoadsorbent-incorporated columns provides high removal efficiency with a maximum adsorption capacity of 243.9 mg/g. We also investigated the influence of initial concentration and solution pH on the removal efficiency of EB. The electrostatic interaction between the adsorbent surface and negatively charged sulfate groups on EB molecules promotes the efficient adsorption of dyes. The equilibrium data matched well with the Langmuir isotherm model, which indicated monolayer dye adsorption onto the adsorbent surface. To extend the application of the current method, we performed further adsorption experiments using other anionic dyes of different colors (Cy5.5, Acid Yellow 25, Acid Green 25, and Acid Red 1). All of these molecules can efficiently be captured under continuous flow conditions, with higher removal efficiency obtained with more negatively charged dyes. These findings clearly demonstrate that the present approach is a useful method for the removal of anionic dye contaminants in aqueous media by adsorption. [ABSTRACT FROM AUTHOR]