Aims
This study aimed to evaluate lysis of Escherichia coli stationary cell cultures induced by the combined action of bacteriophage T5 endolysin (l‐alanyl‐d‐glutamate peptidase) and low doses of ...various cationic agents permeabilizing the outer membrane of Gram‐negative bacteria (polymyxin B, gramicidin D, poly‐l‐lysine, chlorhexidine and miramistin).
Methods and Results
The enzyme activity was assayed with the turbidimetric method. Antimicrobial activity was assessed through the number of colony‐forming units (CFUs); the results of calculation were represented as logarithmic units. The optical microscopy examination of bacterial cells was conducted in the phase‐contrast mode. The use of bacteriophage T5 endolysin in combination with polymyxin B (0·4 μg ml−1) or chlorhexidine (0·5 μg ml−1) made it possible to reduce the number of CFUs by five orders of magnitude; and in combination with poly‐l‐lysine (80 μg ml−1) by four orders, as compared to control. The endolysin was found to be a thermostable protein: it retained ~65% of its initial activity after heating for 30 min at 90°C. Examining the curves of its thermal denaturation revealed the half‐transition temperature to be 56·3 ± 1·0°C. Circular dichroism spectra showed that after recooling the protein restored up to 80% of its native structure.
Conclusions
A substantial synergistic effect of the bacteriophage T5 endolysin and membrane‐permeabilizing compounds was demonstrated.
Significance and Impact of the Study
The study of thermal stability of the bacteriophage T5 endolysin and the quantified assessment of its antimicrobial activity have been done for the first time. The approach examined lays foundations for designing a two‐component preparation which would effectively lyse cells of Gram‐negative pathogens from outside.
Combined dry extract BNO 1016 is a herbal drug commonly used for rhinosinusitis therapy. It is known that a significant role in rhinosinusitis pathogenesis is played by an inflammatory reaction in ...maxillary sinuses of the nasal cavity. At the initial stage of any inflammation the largest
impact is caused by leukotrienes. Major chronic rhinosinusitis (CRS) according to the guideline EPOS-2020 include facial pain as clinical diagnostic criteria for rhinosinusitis. Therefore, it is reasonable to study the analgesic effects of the combined dry extract BNO 1016 on the model of
zymozan- induced hyperalgesia. The tested drug is the combined dry extract BNO 1016 ("Bionorica SE", Germany) at different dose levels. The reference drug is ibuprofen. Leukotriene hyperalgesia was induced by subplantar injection of zymozan into the paw of Wistar rats. Pain threshold was evaluated
with Ugo-Basil analgesimeter and analgesic activity was calculated together with mean effective dose (ED50) with help of the Probit Analysis. The highest analgesic activity was observed at a dose level of 500 mg/kg of BNO 1016 during all time-points of the experiment and reached
169.5% 3h after hyperalgesia onset. The analgesic activity of BNO 1016 at doses of 50 mg/kg in 1h, 2h, 3h after induction hyperalgesia, 150 mg/kg and 500 mg/ kg was credibly higher than that of Ibuprofen at all time-points of the experiment. Based on the experimental data, the index of ED50
for analgesic activity of BNO 1016 was calculated with Probit Analysis. The combined dry extract BNO 1016 shows a high level of analgesic activity in the leukotriene-depended hyperalgesia model, which is very promising for the improvement of treatment of patients with CRS, but additional preclinical
and clinical researches are reasonable.
In this paper, we analyze the contrast of images obtained by scanning electron microscopy (SEM) in the backscattered electron mode, which shows that the contrast on the polished surface of ...multicrystalline silicon (multisilicon) is due to the parameters of misorientation between grains. The contrast values corresponding to special oblique boundaries with various inverse density values of the coinciding nodes of the crystal lattices of neighboring grains forming these boundaries are established. Since the SEM method allows relatively large surface areas of the samples (~1 cm
2
) to be studied, on account of the method proposed here for identifying special oblique boundaries, it is possible to analyze the nature of the interaction of boundaries and their distribution density in the structure, depending on certain crystallization conditions. In SEM studies of multisilicon, this can be important for initial analysis of the structure and further formulation of research problems without the use of special selective etchants that destroy the surface of the studied samples.
The complex correlation between Mn3+ ions and the disordered phase in the lattice structure of high voltage spinel, and its effect on the charge transport properties, are revealed through a ...combination of experimental study and computer simulations. Superior cycling stability is achieved in LiNi0.45Cr0.05Mn1.5O4 with carefully controlled Mn3+ concentration. At 250th cycle, capacity retention is 99.6% along with excellent rate capabilities.
In the present study, the effect of annealing and Ar-plasma treatment on structural, morphological and optical properties of thermally evaporated β-In2S3 thin films has been investigated. During ...Ar-plasma treatment, some interesting results were observed that an array of metallic indium nanostructures was formed over In2S3 film surface with quasi-spherical or spread droplet shapes of an average size of 20–100 nm in the lateral direction and a height of less than 70 nm. Here, the Ar-plasma treatment serves as a new strategy for the self-formation of metallic indium nanostructures over the film surface. Further, the optical absorption of In2S3 films has been enhanced from 104 to 107 cm−1 while the optical band gap energy decreased from 2.71 eV to 2.50 eV after Ar-plasma treatment. The metallic nanostructures loaded on semiconductor surface can act as an electron trap that can effectively prevent the recombination of photo-generated electron-hole pairs.
Indium sulfide (In2S3) is a wide bandgap semiconductor, which is widely used as a window/buffer layer in thin film solar cell applications. In2S3 thin films were deposited using thermal evaporation ...technique and were annealed in sulfur ambient at 200 °C and 250 °C. Further, these films were treated in inductively coupled argon plasma sputtering with an average argon ion energy of 75 eV for 30 s. The paper presents the effect of Ar-plasma treatment on structure, elemental composition, morphology and topography of In2S3 films and the results were reported. Further, the optimized In2S3 layers were continued for plasma etching process with an average argon ion energy of 25 eV to study the effect of plasma etching duration on the growth of metallic indium nanoparticles over the film surface and the results were discussed in detail.
A study of the optical-reflection spectra (250–2500 nm) for the surface of lead sulfide crystals in the initial state and after the formation of a homogeneous ensemble of nanostructures is conducted. ...Single crystals of PbS are grown using the vertical-zone-melting method, with the 100 orientation along the growth axis. Surface nanostructuring is realized in a reactor of high-density argon plasma with a low-pressure high-frequency inductive discharge (13.56 МHz) at the ion energy ~200 eV. The uniform array of stepped lead sulfide nanostructures formed due to plasma treatment is up to 140 nm in height, with cruciform bases having ❬100❭-oriented lateral orthogonal elements 20–60 nm long. It is found that the specular-reflection- and diffuse-reflection spectra for the initial surface of the (100) PbS crystals and for that nanostructured in argon plasma differ significantly. Using the Kubelka–Munk theory of diffuse reflection and the Kumar theory of specular reflection, the band-gap value for the nanostructured surface of (100) PbS crystals is determined as 3.45–3.47 eV, exceeding the value for the initial surface of lead sulfide ~0.4 eV.
BACKGROUND
Fractures of the proximal humerus are more common in older adults. Two options for surgical treatment of the same fractures are routinely performed — primary arthroplasty and ...osteosynthesis with metal fixators. Both methods are most effective in elderly patients for augmentation of the proximal humerus. For this purpose, methyl methacrylate cement or bone allo-/autografts are used. However, the incidence of unsatisfactory functional results after surgery remains high.
AIM OF STUDY
To develop allogeneic graft to strengthen the proximal humerus in the osteosynthesis of a comminuted fracture with a lack of bone tissue which has osteoconductive properties and capable of being a carrier of biologically active substances.
MATERIAl AND METHODS
The head, neck and portion of diaphysis of a fibula of a cadaver were used for a graft. The graft 6–8 cm long was formed and saturated with a collagen solution. Ten patients with 4-fragment fractures of the proximal humerus underwent surgery. X-rays and computed tomography of the operated joint were performed the day after surgery, and then, 6 weeks, 6 months, and one year after the surgery. The follow-up period ranged from 6 to 18 months.
RESUlTS
When evaluating osteoconductive effect in cell culture during saturation with collagen, the content cells on the surface of bone was 5–8 thousand/cm2 and 16–18 thousand/cm2 on the sample, saturated with plasma and growth factors. The studied bone grafts were biocompatible and non-toxic for fibroblast culture. On the surface of the bone graft without collagen adhesion of minimum number of cells occurred. After saturation of the graft with collagen, the adhesive activity of cells on the bone matrix increased, which indicated the presence of an osteoconductive effect. The addition of plasma saturated with growth factors promoted an increase in the number of adhered cells; therefore, the graft can be used as a carrier of biologically active substances. Postoperative X-ray didn’t reveal secondary varus displacement of the head in any patient (except for ununiformed fracture case).
CONClUSION
The developed graft is non-toxic, does not possess immunogenicity, has more pronounced osteoconductive properties in comparison with native bone allografts, which contributes to its colonization with cells. The use of such a graft in clinical practice makes it possible to achieve healing of the fracture and prevent secondary displacement of fragments.
RNA sequencing using the latest single-molecule sequencing instruments produces reads that are thousands of nucleotides long. The ability to assemble these long reads can greatly improve the ...sensitivity of long-read analyses. Here we present StringTie2, a reference-guided transcriptome assembler that works with both short and long reads. StringTie2 includes new methods to handle the high error rate of long reads and offers the ability to work with full-length super-reads assembled from short reads, which further improves the quality of short-read assemblies. StringTie2 is more accurate and faster and uses less memory than all comparable short-read and long-read analysis tools.
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