[Digital PCR as a Highly Sensitive Diagnostic Tool: A Review].

Digital PCR (dPCR) is a nucleic acid quantification method that is widely used in genetic analysis. One of the most significant advantages of dPCR over other methods is the possibility of absolute quantitative determination of genetic material without construction of calibration curves, which allows one to detect even single molecules of nucleic acids, and, hence, provides early diagnosis of diseases. One specific characteristic of dPCR is the detection of the analyzed biological object in each microreaction, followed by the presentation of the analysis results in a binary system, thereby giving the method its name. The key aspects of developing the dPCR method, i.e., from the first devices based on microfluidic chip technology to modern systems capable of measuring a target at a concentration of up to 1 in 100000 copies are shown in the current work. We analyzed the data on the detection of various pathogens using dPCR, as well as summarizing various study results demonstrating the innovativeness of this method. Both the possibilities of multiplex dPCR analysis and its potential in clinical practice are presented. This review also addresses the issue of the role of dPCR in the development of noninvasive methods for analysis of oncological diseases. Possible ways of developing dPCR technology were emphasized, including its use as a "point-of-care" system.

In situ synthesis and characterization of magnetic nanoparticles in shells of biodegradable polyelectrolyte microcapsules.

Hollow microcapsules with the shell composed of biodegradable polyelectrolytes modified with the maghemite nanoparticles were fabricated by in situ synthesis. The nanoparticles were synthesized from the iron salt and the base directly on the capsule shells prepared by "layer by layer" technique. An average diameter of the capsule was about 6.7 µm while the average thickness of the capsule shell was 0.9 µm. XRD, HRTEM, Raman and Mössbauer spectroscopy data revealed that the iron oxide nanoparticles have the crystal structure of maghemite γ-Fe2O3. The nanoparticles were highly monodisperse with medium size of 7.5 nm. The Mössbauer spectroscopy data revealed that the nanoparticles have marked superparamagnetic behavior which was retained up to room temperature due to slow spin relaxation. Because of that, the microcapsules can be handled by an external magnetic field. Both these properties are important for target drug delivery. Based on the Mössbauer spectroscopy data, the spin blocking temperatures TB of about 90K was found for the particles with size D≤5 nm and TB≈250 K for particles with D≥6 nm. The anisotropy constants K were determined using the superparamagnetic approximation and in the low temperature approximation of collective magnetic excitation.

[Comparative efficacy of fixed dose combinations of perindopril with indapamide and captopril with hydrochlorothiazide in patients with high risk hypertension].

Clinical effectiveness and tolerability of o.d. use of fixed dose combinations of perindopril (4 mg) with indapamide (1.25 mg) (Noliprel forte) and captopril (50 mg) with hydrochlorothiazide (25 mg) (Capozide) were compared in a randomized study on 40 patients with I-II degree high and very high risk hypertension. Study duration was 6 months, number of patients in each of parallel groups -- 20. Antihypertensive activity, ability to decrease left ventricular hypertrophy, to improve arterial elasticity and T/P parameter of perindopril (4 mg) -- indapamide (1.25 mg) combination was found to be superior to those of captopril (50 mg) -- hydrochlorothiazide (25 mg) combination.

[Comparison of noliprel and caposide efficacy in patients with arterial hypertension of high risk].

AIM: To compare clinical efficacy and tolerance of fixed combinations of perindopril and indapamide (noliprel), capoten+hydrochlorotiaside (caposide) in arterial hypertension stage I-II of high and very high risk which failed prior monotherapy. MATERIAL AND METHODS: A blind randomized trial in parallel groups recruited 40 patients (20 patients each). The patients received 1 tablet a day noliprel (2 mg/0.625 mg) or caposide (50 mg/25 mg) for 6 months. Target pressure patients were counted. Speed of the pulse wave, blood lipids and electrolytes, left ventricular myocardium posterior wall thickness were estimated. RESULTS: By antihypertensive efficacy and ability to reduce left ventricular hypertrophy and to improve arterial elasticity, low-dose fixed combination (noliprel) was not inferior to caposide (high-dose fixed combination) while by T/P noliprel was more effective than caposide, it lowered cholesterol more but potassium level--less. CONCLUSION: Noliprel has the the same with caposide antihypertensive efficacy and ability to diminish LVH. It has benefits by action on lipid and electrolyte indices.

Quercetin immobilized on silica gel as a solid phase reagent for tin(IV) determination by using the sorption-spectroscopic method.

New chelating sorbents are prepared by 3,3',4',5,7-pentahydroxyflavone adsorption from butanol and acetone-hexane (1:4) solutions, characterized by isotherm of sorption, IR-spectroscopy and studied for pre-concentrating and sorption-spectroscopic determination of Sn(IV). The solid-phase Quercetin with satisfactory analytical characteristics was formed by adsorption from acetone-hexane (1:4) mixture. The quantitative recovery of Sn(IV) from aqueous solution with modified sorbent was observed at pH 1.8-2.2. The tolerance limits of heavy metal ions in the sorption of Sn(IV) are reported. The limit of Sn detection is 0.06 mg l(-1). The linearity of calibration graph has been observed up to 1.2 mg l(-1). The method has been applied to determine Sn in high purity zinc materials.

[Use of a mass spectrometric method for studying the oxygen demand of suspensions of resting Bacillus anthracoides spores]. / Primenenie mass-spektrometricheskogo metoda dlia izucheniia potrebleniia kisloroda suspenziiami pokoiashchikhsia spo Bacillus anthracoides.

Oxygen assimilation by the spore suspensions of Bacillus anthracoides under sterile conditions was continuously registered by means of a modified mass-spectrometry technique using an original reaction vessel. The sensitivity of the technique is 2.10(-2) mcl O2 per 1 mg of dry biomass per hour. The technique made it possible to determine the level of endogenous respiration activity in the spore suspensions of Bacillus anthracoides.

[Oxygen consumption by suspensions of Bacillus anthracoides spores]. / O potreblenii kisloroda suspenziiami spor Bacillus anthracoides

The respiration rate of spore suspensions of Bacillus anthracoides 96 was assayed by mass spectrometry employing a hermetically sealed reaction vessel constructed for this purpose. The rate of respiration was found to depend on the method of preparing suspensions, the duration of their storage at +4 degrees C, the physiological state of spores, and the action of a disinfectant containing chlorine on them.

[Effect of calcium hypochlorite on Bacillus anthracoides spores]. / Deistvie gipokhlorita kal'tsiia na spory Bacillus anthracoides

The sublethal dose of calcium hypochlorite (CH) of 0.2--0.3 mg/ml active chlorine did not cause, after 5 min, morphological changes in the spores of Bacillus anthracoides which could be detected by phase contrast microscopy, or a decrease in the content of dipicolinic acid (DPA) in the spores. Further cultivation of the spores treated with the sublethal dose of CH om MPA resulted in a delay of changes which were typical of normal germination process (swelling, loss of light refraction, decrease in DPA content). The action of the lethal dose of CH (0.2--0.3 mg/ml active chlorine during 1.5 hr or 5.6 mg/ml active chlorine during 1 hr) causes a decrease in light refraction, changes in the dimensions of spores, and a decrease in the content of DPA in the spores by a factor of 4--5. A sharp decrease in the content of DPA in the spores may characterize not only their germination but also their death caused by lethal doses of the chlorine containing disinfectant.

[Change in Bacillus anthracoides spores and their content of dipicolinic acid during germination]. / Izmenenie spor Bacillus anthracoides i soderzhaniia v nikh dipikolinovoi kisloty v protsesse prorastaniia

The content of dipicolinic acid (DPA) was assayed in the spores of Bacillus anthracoides 96 during various stages of its growth. The content of DPA was ca. 10.7 per cent of the dry biomass weight in the seven-day-old culture containing 96 to 99 per cent of the spores in a "starvation" medium. The morphology of the culture was modified, and the content of DPA in the spores fell to 3.6 per cent half an hour after the inoculation into the medium favourable for the growth (MPA). During the following one to four hours of the germination, the refraction index of the spores and the content of DPA in them decreased (the content of DPA to 2 per cent).