A New Oxygen Containing Pyclen-Type Ligand as a Manganese(II) Binder for MRI and 52Mn PET Applications: Equilibrium, Kinetic, Relaxometric, Structural and Radiochemical Studies

A new pyclen-3,9-diacetate derivative ligand (H23,9-OPC2A) was synthesized possessing an etheric O-atom opposite to the pyridine ring, to improve the dissociation kinetics of its Mn(II) complex (pyclen = 3,6,9,15-tetraazabicyclo(9.3.1)pentadeca-1(15),11,13-triene). The new ligand is less basic than the N-containing analogue (H23,9-PC2A) due to the non-protonable O-atom. In spite of its lower basicity, the conditional stability of the [Mn(3,9-OPC2A)] (pMn = −log(Mn(II)), cL = cMn(II) = 0.01 mM. pH = 7.4) remains unaffected (pMn = 8.69), compared to the [Mn(3,9-PC2A)] (pMn = 8.64). The [Mn(3,9-OPC2A)] possesses one water molecule, having a lower exchange rate with bulk solvents (kex298 = 5.3 ± 0.4 ´ 107 s−1) than [Mn(3,9-PC2A)] (kex298 = 1.26´108 s−1). These mild differences are rationalized by density-functional theory (DFT) calculations. The acid assisted dissociation of [Mn(3,9-OPC2A)] is considerably slower (k1 = 2.81 ± 0.07 M−1 s−1) than that of the complexes of diacetates or bisamides of various 12-membered macrocycles and the parent H23,9-PC2A. The [Mn(3,9-OPC2A)] is inert in rat/human serum as confirmed by 52Mn labeling (nM range), as well as by relaxometry (mM range). However, a 600-fold excess of EDTA (pH = 7.4) or a mixture of essential metal ions, propagated some transchelation/transmetalation in 7 days. The H23,9-OPC2A is labeled efficiently with 52Mn at elevated temperatures, yet at 37 °C the parent H23,9-PC2A performs slightly better. Ultimately, the H23,9-OPC2A shows advantageous features for further ligand designs for bifunctional chelators.

Development of a complex anti-radiation protective drug

The article reports results of development of a drug for the prevention and treatment of radiation lesions in animals based on radio modified microorganisms E. coli PL-6 and B. bifidum 1. Aimed at target changing of metabolism, bacteria were exposed to gamma irradiation at doses from 1 to 20 kGy, studying the interaction of microorganisms in the consortium, as well as the safety of produced drugs. Irradiation of E. coli at a dose of 2 kGy led to the appearance of individual cells with polymorphism and having a length exceeding the initial size by 3-7 times. The irradiation of B. bifidum 1 at a dose of 4 kGy contributed to the formation for atypical, polychromic cells, multiple darkening of pigment granules and cell fragments as a result of destruction of microorganisms. The original E. coli PL-6 did not produce the enzymes superoxide dismutaseand catalase, but the metabolites of radiomodified strains of E. coli PL-6 (R10) contained 0.97±0.09 m.c.M/g SOD and 27.38±0.59 mcat/g/ml of catalase activity. In the metabolites of radio-resistant bifidobacteria, as compared with the initial ones, a 1.45-fold excess of peroxidase was recorded.

Synthesis of 6-chloro(dichloro-, trichloro-)-methyl-3-R-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]- quinazolin-2-ones and their modification in reactions with nucleophilic and non-nucleophilic bases

The synthesis of 6-chloro-(dichloro-, trichloro)methyl-3-R-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazolin-2-ones and their modification under the action of nucleophilic and/or basic reagents are described in this article. It was shown that 6-chloro-(dichloro-, trichloro)methyl-3-R-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazolin-2-ones can be prepared by cyclocondensation of 3-(aminophenyl)-6-R-1,2;4-triazine-5(2Н)-ones with chloro-(dichloro-)acetaldehyde or chloral hydrate. The reactivity of the synthesized compounds toward nucleophilic base morpholine and non-nucleophilic base diisopropylethylamine (DIPEA) under different conditions was studied. It was shown that the prepared compounds under the action of morpholine and/or DIPEA can be converted into the products of substitution, elimination or elimination followed by isomerization and substitution. Refluxing of 6-(chloromethyl)-3-R-6,7-dihydro-2Н-[1,2,4]triazino[2,3-с]quinazoline-2-ones with equimolar quantity of morpholine and 10% excess of DIPEA in ethylene glycol monoethyl ether (EGEE) yielded the products on N-alkylation. 6-(Morpholinomethyl)-3-R-2H-[1,2,4]triazino[2,3-с]quinazoline-2-ones were obtained by heating of 6-dichloromethyl-3-R-6,7-dihydro-2Н-[1,2,4]triazino[2,3-с]quinazoline-2-ones with five-fold excess of morpholine in EGEE. Reaction of 3-R-6-(trichloromethyl)-6,7-dihydro-2H-[1,2,4]triazino[2,3-с]quinazolin-2-ones with three-fold excess of DIPEA in EGEE yielded 3-R-2Н-[1,2,4]triazino[2,3-с]quinazoline-2-ones. The physicochemical and spectral characteristics of the prepared compounds were determined and discussed.

The extraction of tin (Sn) from primary tin ore deposits using wet chlorination

More than half of the world’s tin production is from secondary ore deposits. However, along with its depletion, PT Timah Tbk has explored and mined the primary deposits in Belitung, one that is expected to become tin’s new source. Tin was found liberated as cassiterite in the secondary deposits, while in the primary, it was associated with other minerals requiring more complex processing. Therefore, a suitable technology is needed to extract the tin from the primary ore deposits. This research aims to observe the extraction of tin from primary deposits (oxide and skarn ores) using HCl wet chlorination, observed at different temperature (60 – 90°C), HCl concentrations (10 – 50 % excess of stoichiometric amount), leaching time (60 – 300 minutes), and with or without the addition of oxidant (hydrogen peroxide, H2O2). The research found that the highest percentage of tin extraction from oxide and skarn ores was 92.32% and 97.28%, respectively. Both results were achieved at the same optimum condition: temperature of 60°C, 50% excess of HCl, 240 minutes of leaching time, and at two-fold excess of the stoichiometric amount of H2O2. It was concluded that oxidative wet chlorination could be used to recover tin from its primary ore deposits.

Dietary Neu5Ac Intervention Protects Against Atherosclerosis Associated With Human-Like Neu5Gc Loss

Objective: Species-specific pseudogenization of the CMAH gene during human evolution eliminated common mammalian sialic acid N -glycolylneuraminic acid (Neu5Gc) biosynthesis from its precursor N -acetylneuraminic acid (Neu5Ac). With metabolic nonhuman Neu5Gc incorporation into endothelia from red meat, the major dietary source, anti-Neu5Gc antibodies appeared. Human-like Ldlr −/ − Cmah −/− mice on a high-fat diet supplemented with a Neu5Gc-enriched mucin, to mimic human red meat consumption, suffered increased atherosclerosis if human-like anti-Neu5Gc antibodies were elicited. Approach and Results: We now ask whether interventional Neu5Ac feeding attenuates metabolically incorporated Neu5Gc-mediated inflammatory acceleration of atherogenesis in this Cmah −/− Ldlr −/− model system. Switching to a Neu5Gc-free high-fat diet or adding a 5-fold excess of Collocalia mucoid-derived Neu5Ac in high-fat diet protects against accelerated atherosclerosis. Switching completely from a Neu5Gc-rich to a Neu5Ac-rich diet further reduces severity. Remarkably, feeding Neu5Ac-enriched high-fat diet alone has a substantial intrinsic protective effect against atherosclerosis in Ldlr −/− mice even in the absence of dietary Neu5Gc but only in the human-like Cmah -null background. Conclusions: Interventional Neu5Ac feeding can mitigate or prevent the red meat/Neu5Gc-mediated increased risk for atherosclerosis, and has an intrinsic protective effect, even in the absence of Neu5Gc feeding. These findings suggest that similar interventions should be tried in humans and that Neu5Ac-enriched diets alone should also be investigated further.

Human PrimPol Discrimination against Dideoxynucleotides during Primer Synthesis

PrimPol is required to re-prime DNA replication at both nucleus and mitochondria, thus facilitating fork progression during replicative stress. ddC is a chain-terminating nucleotide that has been widely used to block mitochondrial DNA replication because it is efficiently incorporated by the replicative polymerase Polγ. Here, we show that human PrimPol discriminates against dideoxynucleotides (ddNTP) when elongating a primer across 8oxoG lesions in the template, but also when starting de novo synthesis of DNA primers, and especially when selecting the 3′nucleotide of the initial dimer. PrimPol incorporates ddNTPs with a very low efficiency compared to dNTPs even in the presence of activating manganese ions, and only a 40-fold excess of ddNTP would significantly disturb PrimPol primase activity. This discrimination against ddNTPs prevents premature termination of the primers, warranting their use for elongation. The crystal structure of human PrimPol highlights Arg291 residue as responsible for the strong dNTP/ddNTP selectivity, since it interacts with the 3′-OH group of the incoming deoxynucleotide, absent in ddNTPs. Arg291, shown here to be critical for both primase and polymerase activities of human PrimPol, would contribute to the preferred binding of dNTPs versus ddNTPs at the 3′elongation site, thus avoiding synthesis of abortive primers.

Study of the chemical removal of phosphorus at the municipal wastewater treatment facilities of the Samara urban district

Определены параметры реагентного удаления фосфора из сточных вод г. Самары. Исследования проводились методом пробного коагулирования исходной и осветленной сточной воды и иловой смеси аэротенков. Установлено, что при одинаковых дозах реагента наиболее глубокое удаление фосфора происходит из иловой смеси. При использовании сульфата алюминия удаление фосфора фосфатов происходило на 0,3–1,6 мг/л глубже, чем при обработке полиоксихлоридом алюминия «Аква-Аурат-30Ô», в зависимости от исходных концентраций. Содержание остаточного алюминия в очищенной воде при использовании «Аква-Аурат-30Ô» в среднем было на 8% ниже, чем при использовании сульфата алюминия, – 0,1680,221 мг/л против 0,1730,274 мг/л. Сравнительные результаты реагентной обработки коагулированием с применением флокулянтов и без них показали, что дополнительное дозирование флокулянта не привело к повышению эффективности удаления фосфора. Определено, что при концентрации фосфора фосфатов в иловой смеси 3,7–5,2 мг/л для достижения эффективности очистки выше 85% требовался 1,3–1,8-кратный избыток сульфата алюминия, а при более низких концентрациях 1,23–1,87 мг/л данная эффективность достигалась лишь при 3,1–5-кратном избытке реагента. Результаты исследований использованы в проекте реконструкции сооружений доочистки канализационных очистных сооружений г. Самары, которым предусмотрено химическое удаление фосфора в дополнение к улучшенному процессу биологического удаления фосфора. Принятая расчетная доза сульфата алюминия 10 мг/л по товарному продукту позволит снизить концентрацию фосфатов после основной ступени биологической очистки с 0,53 до 0,2 мг/л. The parameters of the chemical removal of phosphorus from wastewater in Samara have been determined. The studies were carried out by the method of trial coagulation of raw wastewater, primary effluent and mixed liquor from the aeration tanks. It was found that at the same doses of the chemical, the enhanced removal of phosphorus occurs from the sludge mixture. While using aluminum sulfate, the removal of phosphorus phosphates was enhanced by 0.3–1.6 mg/l more than while adding Aqua-Aurat-30TM aluminum polyoxychloride, depending on the initial concentrations. The concentration of residual aluminum in the effluent while using Aqua-Aurat-30TM was on average 8% lower than while using aluminum sulfate – 0.168–0.221 mg/l versus 0.173–0.274 mg/l. Comparative results of the chemical coagulation with the use of flocculants and without them showed that additional dosing flocculant did not result in an increase in the efficiency of phosphorus removal. It was determined that to achieve above 85% treatment efficiency at a phosphorus-phosphate concentration in the mixed liquor of 3.7–5.2 mg/l, a 1.3–1.8-fold excess of aluminum sulfate was required, and at lower concentrations of 1.23– 1.87 mg/l, this efficiency was achieved only with a 3.1–5-fold excess of the chemical. The research results were used in the project of upgrading a tertiary treatment plant at the Samara wastewater treatment facilities, that provided for the chemical removal of phosphorus in addition to the enhanced process of biological removal of phosphorus. The accepted calculated dose of aluminum sulfate 10 mg/l for a commercial product will reduce the concentration of phosphates after the main stage of biological treatment from 0.53 to 0.2 mg/l.

Wertheim’s Operation. Problems and achievments

Aim. Analysis of modern modification of Wertheim’s operation and its results in Bukovina region for last 10 years.Methods. Analysis of literature in internet. Data about morbidity and mortality of cancer colli uteri in Chernivtsi Oncology Center.Results. An original description of the technique of radical hysterectomy for cervical cancer by Wertheim is presented. Modifications of the Wertheim operation with various classifications of interventions are considered. In first class of this classification are included extra fascial hysterectomies without resection of tissues, lymph nodules and fascia of pelvis which directly contradicts the principles of Wertheim's operation. The results of radical laparoscopic hysterectomy for cervical cancer are discussed. In 2019 trials, there was an almost three-fold excess of relapses after laparoscopic hysterectomies compared to open operations. The issues of the epidemiology of cervical cancer in Ukraine and Bukovina are considered. The incidence of cervical cancer in the Chernivtsi region was about 70 patients per year, or 8.4 per 100,000 population (data from 2016-2018). Cervical cancer mortality was from 40 to 43 people annually or 4.3-4.7 per 100,000 population. Wertheim’s operation is performed annually in 26-34 women and is practically not accompanied by complications and mortality.Conclusion. Wertheim’s operation is safe and unique method for treatment of cervical cancer.

Rearrangement of spiroderivatives of 1,3-benzo(naphtho)dioxin-4(1)-ones as a new method of synthesis of xanthene bromo derivatives

We have proposed a method for the synthesis of previously unknown bromo xanthenes using the reagent PBr3/DMF as a rearrangement initiator. Bromo derivatives of xanthenes in the form of organic perchlorates were prepared by reacting the corresponding benzo(naphtho)dioxin-4(1)-ones with a three-fold excess of Vilsmeier-Haack PBr3/DMF reagent at 1100C for 2 hours, followed by the addition of sodium perchlorate. The conditions for the synthesis of formyl derivatives of xanthenes under conditions of acid hydrolysis were selected. The structure of the compounds was confirmed by 1H and 13C NMR spectral data and mass spectrometry. Preliminary studies showed that it is possible to selectively replace the dimethylamino group and the bromine atom with various nucleophiles in bromo derivatives of xanthenes, which opens up wide possibilities for the synthesis of low-molecular building blocks and dyes.

AB0632 СOMORBIDITIES AND DRUG-INDUCED LIVER INJURY DUE TO NSAIDS INTAKE IN PATIENTS WITH GOUT

Background:One of the side effects of NSAIDs is hepatotoxicity or Drug-Induced Liver Injury (DILI). Despite the short course of NSAIDs, the patients with gout may develop DILI. At the same time, besides NSAIDs, there are additional factors that affect the functional state of the liver: demography, comorbidities or concomitant medication (1).Objectives:To determine comorbidities associated with the risk of DILI when taking NSAIDs during the attack of gouty arthritis.Methods:Our retrospective study included 200 patients with GA. Inclusion criteria for the study: presence of gout (ACR, 1977), initially normal serum ALT level, NSAIDs as anti-inflammatory drugs in gout. Exclusion criteria: presence of a known liver disease. All patients were divided into 2 groups: those who developed DILI (n = 86) and the control group without cytolysis during NSAID treatment (n = 114). The severity of the cytolytic syndrome was revealed as follows: mild form (2-3-fold excess of the ALT norm) in 81,4 % (n = 70); moderate (3-5 times higher ALT) in 15.1% (n = 13); severe (5-10 fold excess of ALT) in 3.4% (n = 3). The mean age of 55 (49-60) years and 54 (44-59.5) years as well as the sex distribution (men made 90.1% and 93.3%, respectively) were compatible in both groups (р>0,05). When studying the age distribution, statistical differences were revealed in the groups under 52 years (p<0,05), so, this parameter was included into logistic regression model. During the follow-up period, all patients took NSAIDs above average doses. Patients in both groups were comparable in duration of gout. The following parameters were compared: AH, IHD, diabetes mellitus, obesity, dyslipidemia, metabolic syndrome according to ATPIII, CKD, alcohol abuse, age under 52.Results:After conducting logistic regression analysis, the next comorbidities have been revealed to be statistically significant: obesity (OR – 2,15; 95%CI 1,16-3,98), dyslipidemia (OR – 3,41; 95% CI 1,56-7,44) and alcohol abuse (OR – 2,45; 95%CI 1,22-4,91). Worth to note that age under 52 was also a risk factor for DILI (OR – 2,14; 95%CI 1,13-4,04). Thus, among our patients, the younger ones with an unhealthy lifestyle and no serious comorbidities, including cardiovascular, were at a greater risk for developing DILI while taking NSAIDs during the gout attack.Conclusion:In the study group of patients with gout, the hepatotoxicity (cytolysis syndrome) risk due to NSAIDs intake increased in younger patients in the presence of signs of metabolic syndrome (obesity, dyslipidemia) and alcohol abuse.References:[1]European Association for the Study of the Liver. EASL Clinical Practice Guidelines Drug-induced liver injury. J. of Hepatology. 2019; 30: 1-40.Disclosure of Interests:None declared.