[Modern biotechnologies in estimation of genetic diversity of Ukrainian varieties of hop (Humulus lupulus L.)].

Genetic variety estimation of hop gene pool using DNA-typing of highly polymorphic microsatellite loci and optimization of introduction to the culture of in vitro conditions is the important stage of national varieties resources forming, basis of modern nursery and protect mean of varieties property, and also it is necessary for development of molecular methods of selection of planting-stocks free from pathogens.

Fully vs. partially integrated services for TB-HIV in Myanmar: a health services review and a cohort study.

In Myanmar, integrated services for tuberculosis (TB) and human immunodeficiency virus (HIV) are operated either fully (as one single unit) or partially (each vertical programme provides both services). To review the fully and partially integrated services for TB-HIV and to assess their TB treatment outcomes. We analysed the compiled service database and conducted a cohort study on newly registered TB-HIV patients in 12 townships in Myanmar. No significant association between region/state and types of integration was detected. Townships with partially integrated services had a significantly larger population size, higher proportion of urban population as well as higher TB and TB-HIV case notification rates; however, the cartridge-based Xpert® MTB/RIF assay was used less frequently than in townships with fully integrated services. Treatment completion rate and unfavourable outcomes were not significantly different between the two models, although fully integrated services reported a higher cure rate. These mixed results suggest that during expansion of fully integrated services, the progress of treatment outcomes should be monitored carefully. .

High prevalence and incidence of tuberculosis in people living with the HIV in Mandalay, Myanmar, 2011-2017.

SETTING: Two human immunodeficiency virus (HIV) clinics providing antiretroviral therapy (ART), Mandalay, Myanmar. OBJECTIVE: To assess prevalent TB at enrolment, incident TB during follow-up and associated risk factors in adult people living with HIV (PLHIV) between 2011 and 2017. DESIGN: Cohort study using secondary data. RESULTS: Of 11 777 PLHIV, 2911 (25%) had prevalent TB at or within 6 weeks of enrolment. Independent risk factors for prevalent TB were being male or single/widowed, daily alcohol consumption, CD4 count 200 cells/µl and anaemia. During 6 years follow-up in 8866 PLHIV with no prevalent TB, the rate of new TB was 2.9 per 100 person-years (95%CI 2.6-3.1). Cumulative TB incidence was 9.6%, with 370 (72%) of 517 new TB cases occurring in the first year. Independent risk factors for incident TB were being male and anaemia. Incident TB was highest in the first year of ART, in PLHIV with CD4 counts 200 cells/µl and those not receiving isoniazid preventive therapy (IPT). Incident TB declined with time on ART and rising CD4 counts. CONCLUSION: Prevalent and incident TB were high in PLHIV in the Mandalay clinics. Consideration should be given to earlier TB diagnosis using more sensitive diagnostic tools, effective ART and scaling up IPT.

Accuracy of routine laboratory diagnosis of malaria in the United Kingdom.

AIMS: To study the accuracy of routine laboratory diagnosis of malaria with the aim of improving accuracy in diagnosis in the future. METHODS: A comparative study was made of all blood films submitted to two laboratories in London providing a slide-diagnostic service for malaria. RESULTS: There were 17 Plasmodium ovale infections, and of these only five (29.4%) were correctly diagnosed by the submitting laboratory; whereas of 210 other single species infections, 162 (77.1%) were correctly diagnosed (chi 2 = 18.4, p < 0.0001). There were six patients with mixed infections; only one (16.7%) was correctly diagnosed, whereas of 227 single species infections, 167 (73.6%) were correctly diagnosed (p = 0.007, using Fisher's exact test). There was no significant association between the presence of technical faults or numerous platelets and incorrect diagnosis. CONCLUSIONS: Plasmodium ovale and mixed infections were diagnosed incorrectly significantly more often than other species. The presence of technical faults or numerous platelets had no significant effect on whether or not submitting laboratories correctly diagnosed malaria.

An outbreak of penicillin resistant Streptococcus pneumoniae investigated by a polymerase chain reaction based genotyping method.

AIMS: To characterise the genotypes of penicillin resistant Streptococcus pneumoniae infecting patients in a care of the elderly ward and to study its transmission in a hospital environment. METHODS: Isolates of S pneumoniae were cultured from specimens obtained from patients who had been admitted to a care of the elderly ward where an outbreak had occurred. Penicillin resistant S pneumoniae were also obtained from a series of surveillance throat swabs taken from patients in the same ward. In addition, all penicillin resistant S pneumoniae isolated from specimens submitted for culture at the time of the outbreak were included. Four sensitive strains isolated from a routine microbiology laboratory were included as controls. A simple polymerase chain reaction (PCR) based genotyping method for the penicillin binding protein (PBP) genes 1a, 2x, and 2b was used to characterise the genotypes. RESULTS: Nine patients were infected with serotype 9 S pneumoniae. Four of these patients died; two deaths were directly attributable to the infection. Tested against a battery of haemolytic streptococci and other organisms found in the respiratory tract, only two false positive reactions for PBP 2x were found among S mitis. The method demonstrated that the outbreak strain had altered PBP 1a, 2b, and 2x genes, a pattern clearly distinguishable from other penicillin resistant strains isolated at the same time. CONCLUSIONS: This method is simple to perform and would enable many laboratories to characterise the genotype of penicillin resistant S pneumoniae and investigate transmission in their hospitals.

Assessment of the efficacy of a low temperature hydrogen peroxide gas plasma sterilization system.

The STERRAD 100 sterilization system (Johnson & Johnson Medical Ltd) uses low temperature hydrogen peroxide gas plasma for sterilization of heat labile equipment. The efficacy of the machine was tested by contaminating a standard set of instruments with different organisms and using a filtration method to assess recovery of organisms from the wash fluids of instruments post-sterilization. Experiments were performed under clean (the organism only) and dirty (organism mixed with egg protein) conditions. A parallel study conducted using a 3M STERIVAC ethylene oxide sterilizer could not be completed owing to closure of the ethylene oxide plant. For sterilization of instruments with long and narrow lumens, hydrogen peroxide adaptors are necessary. The STERRAD 100 sterilizer can achieve effective sterilization of heat labile instruments with a reduction of 6 log10 cfu/mL of organisms tested. This method has the advantages over ethylene oxide sterilization of safety, ease of maintenance and no requirement for aeration time.

Improved detection of Mycobacterium spp. using the Bactec MGIT 960 system.

Until 1987, the notification rate for mycobacterial infection was on the decline; however, it now appears to be increasing once more. The reason for this may be multifactoral and include improved reporting of diagnosed cases, increased infection of an ageing population, homelessness, immunosuppression (e.g. due to human immunodeficiency virus infection), and immigration of people from countries where tuberculosis is endemic. This rising incidence and the increasing importance of resistant organisms mean that rapid identification by the clinical microbiology laboratory is required, and this is where an automated detection system can be an advantage. Over a two-year period, 2743 clinical specimen were examined for Mycobacterium spp. using the Bactec MGIT 960, and 286 were positive. Time to detection ranged from three to 14 days (mean: 9.3 days), and M. tuberculosis was recovered from 214 (75.5%). Contamination rate was higher (8.6%) than with manual methods, however. On balance, the Bactec MGIT 960 system proved a valuable tool in the routine microbiology laboratory.

[Substantiation of application of the anterior trans-pyramidal approach in skull base tumors]. / Obhruntuvannia zastosuvannia perednikh transpiramidnykh dostupiv do pukhlyn osnovy cherepa.

The microtopographic-anatomic substantiation of anterior transpyramid approaches to the skull base tumors was conducted. The transpyramid approaches introduction in clinical practice had permitted to improve surgical treatment results in patients with the difficult of access skull base tumors. Indications and choice of approach depending on the kind, localization and tumor spread in the skull base in the temporal bone pyramid part were substantiated.

[Characteristics of quantal release of glutamate and GABA in synapses between retinal ganglion cells and superior colliculus neurons in coculture].

We investigated features of quantal release of glutamate and GABA in synapses between retinal ganglion cells (RGC) and superior colliculus (SC) neurons in coculture using dual patch-clamp technique. The main quantal characteristics of neurotransmitters release were defined on the basic of quantal analysis. Number of released quanta distributions for both neurotransmitters were corresponded to the binomial law. It was shown that evoked postsynaptic currents (PSC) in SC neurons as response to generation of action potential (AP) in RGC were mediated by simultaneous release at least from 2 to 14 quanta of glutamate and 2 quanta of GABA. Thereby high efficacy of excitatory and inhibitory signals transmission is guaranteed in retinocollicular projections. It is supposed that multiquantal character of the neurotransmitters release can be related to simultaneous involvement of several closely adjacent excited terminals, each of which possesses one active zone, or by one terminal with several.

[Pretective action of peptide pro-gly-pro on electrophysiological characteristics of cultured hippocampal neurones during excitotoxic damage].

Electrophysiological characteristics of hippocampal neurones cultured with Pro-Gly-Pro peptide were studied using glutamate excitotoxisity model (excitotoxic damage was induced by 100 mkM glutamate application during 5 min). It was found that negative changes in neurones cultured with 10 mcM Pro-Gly-Pro were less prominent if compared with control ones. Culturing with the peptide significantly affected the following parameters: resting potential (-55 +/- 4 mV in control; -29 +/- 6 MV after glutamate application; -38 +/- 5 MV cultured after glutamate application), action potential amplitude (91 +/- 4; 65 +/- 5; 84 +/- 5 mV), duration (4,3 +/- 0,4; 9,5 +/- 1,6; 5,2 +/- 0,7 ms), depolarization (56 [38, 84]; 27 [21, 35]; 46 [28, 62] MV/Ms) and repolarization (-29 [-38, -27]; -20 [-21, -18]; -29 [-33, -22] M(V)/MS) rates. The data obtained suggest that PGP exhibit its neuroprotective properties on a level of basic electrophysiological characteristics, appropriate cellular mechanisms require further investigations.

[Pre- and postsynaptic expression mechanisms of long-term depression in rats glutamatergic primary afferent synapses on dorsal horn spinal cord neurons in co-culture].

In co-culture of dorsal root ganglion (DRG) and dorsal horn (DH) neurons we studied the long-term depression (LTD) caused by 5 sec(-1) low-frequency stimulation (LFS) of DRG neurons. Dual whole-cell patch clamp recording in the pairs of DRG and DH neurons was used. The monosynaptic AMPA-receptor mediated eEPSC initiated in DH neurons by LFS of DRG neurons were analyzed. LFS with durations from 60 to 360 sec affected the LTD magnitude and involved the different LTD expression mechanisms. The amplitude and variability of miniature EPSC were not changed during LTD. LFS during 60 sec did not alter the eEPSC amplitudes, but significantly increased the coefficient of variation (CV; 56.8% +/- 11.5%, n = 5; P < 0.002) and the paired-pulse ratio (PPR; 37.8% +/- 11.4%, n = 5; P < 0.05), and decreased the release probability (p; 21.9% +/- 5.6%, n = 5; P < 0.05) calculated using binomial analysis. LFS for 120 sec led to LTD (eEPSC decreased to 14% +/- 3.3%, n = 13; P < 0.005); no changes in CV, PPR and p were found. LFS for 160, 200, 240 and 360 sec induced robust LTD: eEPSC decreased to 37.3 +/- 4.3 (n = 9); 48.1 +/- 3.5 (n = 7); 58.3 +/- 2.5 (n = 8) and 57.3% +/- 2.8% (n = 8), respectively; P < 0.001. LTD induced by such LFS durations was not accompanied by significant changing in PPR and p, but showed an increase in CV: 24.4 +/- 8.6 (n = 6); 35.1 +/- 11.2 (n = 6); 37.7 +/- 12.8 (n = 7), and 38.1% +/- 9.3% (n = 8), respectively. LTD magnitude was correlated with the enhancement in CV value at different LFS duration (r = 0.96). Our data suggest that the different mechanisms could be involved in LTD expression according to duration of LFS. Thus, 60 sec LFS induces presynaptic changes, but no change in eEPSC, whereas LTD elicited by 120 and 160 sec LFS affected the postsynaptic site. LTD initiated by longer LFS (200 - 360 sec) probably was caused by a silencing of functional synapses without changes in glutamate release probability.

[Changes in the kinetics of calcium signals in response to high frequency stimulation in the cultured hippocampal neurons].

Dynamic changes in the intracellular free Ca2+ concentration ([Ca2+]i) were studied in hippocampal cultured neurons using fluorescent Ca(2+)-indicator dye Indo-1 and somatic whole-cell recordings. During the tetanus stimulation Ca(2+)-transient increased their amplitude up to a steady-state level during repetitive stimulation. We identified two groups of neurons based on Ca-signal dynamics after the end of stimulation: the first group (n = 24) with the monoexponential decay of [Ca2+]i direct after the end of the tetanus; the second group (n = 32) with the monoexponential delayed [Ca2+]i decay after the end of the tetanus, the duration of delay varied from 1 to 27 s and depended on duration and frequency of stimulation. Peak amplitudes of Ca(2+)-transients were statistically different between the first (1820 +/- 195 nM, n = 24) and the second (2618 +/- 165 nM, n = 23) groups. A linear dependence between decay time constant and frequency of stimulation was found for the second group of neurons only. In all cases when the delayed decay was observed the decay time constant changed reliably after emergence of delayed decay; the average rise made up 41 +/- 8%. We suggest dynamic changes and essential rise in the intracellular free Ca2+ concentration arise from the presence of intracellular low-affinity buffer. This statement is to be further tested using pharmacological approach.

[Electrical properties of retinal ganglion cells of rats with streptozotocine-induced diabetes].

On isolated retinal preparation from STZ-induced diabetic rats in whole-cell configuration the basic electrical properties of retinal ganglion cells (RGC) were studied. It was shown that on 8th week after STZ maximal depolarization-induced firing frequency is reduced and decay time constant of high-frequency stimulation-induced calcium signals is increased as compared to controls. The data obtained suggest functional changes in RGC of STZ-induced diabetic rats, possible mechanisms of such changes are discussed.

[Calcium signaling induced by tonic firing in the rat eye retinal ganglion cells].

On rat retinal preparation in whole-cell mode retinal ganglion cells (RGC) tonic firing induced calcium signals were recorded and their modulation by Kv3 potassium channels was studied. RGC depolarization with 500 ms current steps caused tonic action potentials (AP) generation and development of calcium signals which amplitude depended quite linearly on mean AP frequency with mean slope 1.4 +/- 0.2 s x nmol/l (n = 5). The calcium signals mean tau of decay value was 6.8 +/- 1.4 s (n = 5). After application of tetraethylammoniun (500 MM), which in such concentration blocks Kv3.1/Kv3.2 potassium channels, a decrease in firing frequency, an increase of AP width and a decrease of afterhyperpolarization amplitude were observed. In the presence of the blocker the calcium signal amplitude vs mean AP frequency dependency slope mean value increased to 2.1 +/- 0.3 s.nmol/l. The calcium signals tan of decay not changed significantly, the mean value was 8.9 +/- 1.6 s (n = 5). Thus, voltage-dependent Kv3.1/Kv3.2 potassium channels, which play a key role in tonic firing pattern generation in RGC, also modulate appropriate calcium signals and prevent the cells from significant intracellular calcium increasing and its possible cytotoxic action.

[Characteristics of sensory neurotransmission in co-culture of neurons from the dorsal root ganglion and dorsal horn spinal cord in rats].

We examined properties of chemical neurotransmission at the level of primary afferent inputs into spinal cord with the new easy-to-use in vitro model of contiguously-cultivated dissociated both the dorsal root ganglion neurons (DRG) and the dorsal horn spinal cord neurons (DHSC) from newborn rats. The results of our studies showed the presence of excitatory and inhibitory DRG neurons synapses on the cells of DHSC. The excitatory afferent signaling in such synapses was mediated by presynaptic release of glutamate and a following activation of both NMDA- and non-NMDA-receptor subclasses. In these cases the activation of non-NMDA-receptors makes a main contribution to realization of excitatory postsynaptic effects. Either glycine- or GABA-ergic DRG neurons were involved in transmission of inhibitory signals to the DHSC neurons. However, in vast majority of examined neuronal pairs the inhibitory synaptic transmission was mediated by presynaptic release of glycine. As distinct from the previous similar methods, an in vitro model of co-culture of both the DRG and the DHSC neurons proposed here allows to use comprehensively modem technical approaches for examination of the transmission of somatosensory information from the periphery to the CNS. The described model could be acceptable for detailed investigation of specific properties of primary afferent synapses.

[Nonuniform distribution and contribution of the P- and P/Q-type calcium channels to short-term inhibitory synaptic transmission in cultured hippocampal neurons].

In the present study, we investigated the sensitivity of GABAergic short-term plasticity to the selective P- and P/Q-type calcium channels blocker omega-agatoxin-IVA. To block the P-type channels we used 30 nM of this toxin and 200 nM of the toxin was used to block the P/Q channel types. The evoked inhibitory postsynaptic currents (eIPSC) were studied using patch-clamp technique in whole-cell configuration in postsynaptic neuron and local extracellular stimulation of single presynaptic axon by rectangular pulse. The present data show that the contribution of P- and P/Q-types channels to GABAergic synaptic transmission in cultured hippocampal neurons are 30% and 45%, respectively. It was shown that the mediate contribution of the P- and P/Q-types channels to the amplitudes of eIPSC is different to every discovered neuron. It means that distribution of these channels is non-uniform. To study the short-term plasticity of inhibitory synaptic transmission, axons of presynaptic neurons were paired-pulse stimulated with the interpulse interval of 150 ms. Neurons demonstrated both the depression and facilitation. The application of 30 nM and 200 nM of the blocker decreased the depression and increased facilitation to 8% and 11%, respectively. In addition, we found that the mediate contribution of the P- and P/Q-types channels to realization of synaptic transmission after the second stimuli is 4% less compared to that after the first one. Therefore, blocking of both P- and P/Q-types calcium channels can change the efficiency of synaptic transmission. In this instance it facilitates realization of the transmission via decreased depression or increased facilitation. These results confirm that the P- and P/Q-types calcium channels are involved in regulation of the short-term inhibitory synaptic plasticity in cultured hippocampal neurons.

[Effect of 4-aminopyridine-sensitive potassium current on high frequency tonic firing of the rat retinal ganglion cells].

High frequency firing properties of the rat retinal ganglion cells and role of 4-AP-sensitive potassium current in firing generation were studied using whole cell patch-clamp techniques. Potassium channel blocker 4-AP (0,2 mM) reduced depolarization-evoked firing rate by 62% (from 50 +/- 5, n = 12 to 19 +/- 2 Hz, n = 7). Single action potential parameters were affected: half-width was increased by 133% (from 1,2 +/- 0,1, n = 12 to 2,8 +/- 0,3 ms, n = 7), decay slope was decreased by 63% (from 102 +/- 11, n = 12 to 38 +/- 7 mV/ms, n = 7) and afterhyperpolarization amplitude by 83% (from 18 +/- 2, n = 12 to 3 +/- 2 mV, n = 7). 4-AP application (0,2 mM) reduced potassium current amplitude of the retinal neurons. 4-AP-sensitive current was obtained by digital subtraction of current that was registered in the presence of the blocker from control current records (1,61 +/- 0,22 nA, n = 6). 4-AP-sensitive current was equal to 0,40 +/- 0,09 nA (n = 6). Thus, moderate (25%) reducing of potassium current amplitude leads to essential changes in firing properties of retinal neurons. 4-AP-sensitive residual current was similar to Kv3.1/Kv3.2 potassium currents that were described in literature previously. Moreover, we excluded the possibility of 4-AP influence on Kv1 channels by specific blocker alpha-dendrotoxin (100 nM) application. Such applications significantly affected neither firing frequency nor single action potential parameters. The data obtained suggest that 4-AP-sensitive current plays a key role in high frequency firing generation in the rat retinal ganglion cells. We assume that the 4-AP-sensitive current is mediated by Kv3.1/Kv3.2 conductance.