What the distribution of sperm size can tell about the stability of spermatogenesis in hybrid frogs Pelophylax esculentus

Interspecies hybrid frogs Pelophylax esculentus and one of its parental species Pelophylax ridibundus inhabit the Siversky Donets center of diversity of water frogs in Eastern Ukraine. These frogs can crossbreed and form progeny in population systems which are called hemiclonal (HPS). Such systems have their own exceptional features which make them interesting for studying. The Lower Dobrytskiy Pond, which is situated in the National Nature Park “Homilshansky lisy” and is a part of Siversky Donets river basin, is on focus. Current work is devoted to the combination of two methods of spermatogenesis investigation. First, using the method of Ag-staining we observed high variability of meiotic chromosomal plates in testes of 24 adult male water frogs P. esculentus (2n=26). Only one male had 100% of full meiotic plates with no aneuploid plates. A significant amount of studied males (21/24) produced aneuploid chromosomal plates (4-68% of the total amount of meiotic plates). This may lead to a decrease in their fertility or even to their entire sterility. Also, we have not observed any chromosomal meiotic plates in two of 24 males. Some males (8/24) even produced meiotic chromosomal plates with 26 bivalents (i.e. 4n germ cells) which may testify about the ability to produce diploid sperm. Further, the lengths of urinary sperm cells’ heads were measured. Finally, we performed an analysis of both meiotic chromosomes in testes and the distribution of sizes of urinary sperm cells’ heads of hybrid water frogs Pelophylax esculentus from Siversky Donets basin to find out if there is a link between these two features. No difference in sperm heads lengths was found between males producing moderate and low amounts of sperm. Based on the data of meiotic plates all males were assigned into five categories via PCA (principal component analysis). A significant difference in sperm heads lengths was found within the category I (males with mostly full meiotic plates). The analysed data shows that each male from the studied population has his own unique features. No direct link between sperm cells size and features of meiotic chromosomes in testes was found

Case category of noun in the English language

The given article is devoted to the phenomenon of case. It deals with the problem of the category of case in the English language. The article presents the origin of the term “case”, definition of the notion and various approaches to the category of case in the English language study: “the theory of positional cases”, “the theory of prepositional cases”, “the theory of limited case”, “the theory of possessive postposition”; their critical assessment

The study of titanium oxynitride coatings solubility deposited by reactive magnetron sputtering

To improve hemocompatibility of cardiovascular stents the coatings based on titanium oxides and oxynitrides were used. In the present work the morphology, surface properties (wettability and surface energy), and in vitro solubility of the ternary system Ti-N-O coating were investigated. Experimentally, low dissolution rate of the coating in saline NaCl (0,9%) was confirmed. Instrumental methods of quantitative analysis (XRF, AES) revealed that the Ti-N-O coating is chemical-resistant and does not change the qualitative and quantitative composition of body fluids

Protective Effect of Meso-Tetrakis-(3,5-di-tert-butyl-4-hydroxyphenyl)porphyrin on the In Vivo Impact of Trimethyltin Chloride on the Antioxidative Defense System

The in vivo effect of trimethyltin chloride (Me(3)SnCl), free base meso-tetrakis(3,5-di-tert-butyl-4-hydroxyphenyl)porphyrin (R′(4)PH(2)) and their equimolar mixture, on the enzymatic activity of catalase (CAT), superoxide dismutase (SOD), and on the total content of free sulfhydryl groups has been studied in rat liver and kidney. It was demonstrated that the simultaneous treatment of tested animals with the combination of Me(3)SnCl and R′(4)PH(2) reduced the toxic impact of Me(3)SnCl

Interaction between the Rev1 C-Terminal Domain and the PolD3 Subunit of Polζ Suggests a Mechanism of Polymerase Exchange upon Rev1/Polζ-Dependent Translesion Synthesis

Translesion synthesis (TLS) is a mutagenic branch of cellular DNA damage tolerance that enables bypass replication over DNA lesions carried out by specialized low-fidelity DNA polymerases. The replicative bypass of most types of DNA damage is performed in a two-step process of Rev1/Polζ-dependent TLS. In the first step, a Y-family TLS enzyme, typically Polη, Polι, or Polκ, inserts a nucleotide across a DNA lesion. In the second step, a four-subunit B-family DNA polymerase Polζ (Rev3/Rev7/PolD2/PolD3 complex) extends the distorted DNA primer-template. The coordinated action of error-prone TLS enzymes is regulated through their interactions with the two scaffold proteins, the sliding clamp PCNA and the TLS polymerase Rev1. Rev1 interactions with all other TLS enzymes are mediated by its C-terminal domain (Rev1-CT), which can simultaneously bind the Rev7 subunit of Polζ and Rev1-interacting regions (RIRs) from Polη, Polι, or Polκ. In this work, we identified a previously unknown RIR motif in the C-terminal part of PolD3 subunit of Polζ whose interaction with the Rev1-CT is among the tightest mediated by RIR motifs. Three-dimensional structure of the Rev1-CT/PolD3-RIR complex determined by NMR spectroscopy revealed a structural basis for the relatively high affinity of this interaction. The unexpected discovery of PolD3-RIR motif suggests a mechanism of “inserter” to “extender” DNA polymerase switch upon Rev1/Polζ-dependent TLS, in which the PolD3-RIR binding to the Rev1-CT (i) helps displace the “inserter” Polη, Polι, or Polκ from its complex with Rev1, and (ii) facilitates assembly of the four-subunit “extender” Polζ through simultaneous interaction of Rev1-CT with Rev7 and PolD3 subunits

Acute phlegmonous appendicitis in rare variant of appendix diverticulum (case report)

Background. Appendicitis-like diverticulitis is considered a rare disease and is usually the subject of clinical reports. Clinical manifestations of this pathology is similar to those of appendicitis, which is why a preoperative diagnosis is made quite rarely. When carrying out the study, we considered a clinical case of acute phlegmonous appendicitis with a rare variant of the appendix wall diverticulum.Material and methods. To assess clinical cases, a retrospective analysis of medical documentation (medical records of patients with diverticulitis in particular) was used. The assessment of clinical symptoms was accompanied by using general clinical, histological and microbiological methods.Results. Patient I., 62 years old, was diagnosed with acute appendicitis. An urgent appendectomy was carried out, during which the vermiform process was removed. It was located retrocecally, in the adhesive process and loose infiltrate. The length of the process is 7–8 cm, its diameter is 1–1,5 cm. 6 diverticula up to 0,7 cm in size are visible. When the process is cut, the pyoid contents protrudes from its lumen. In addition, the appendix removed during appendectomy was sent for pathological study. A standard histopathological study was carried out with the step-like sectioning and hematoxylin and eosin staining.Conclusion. From the results of a pathological study, it was found that the layers of the vermiform process wall with diverticula are diffusely infiltrated by polymorphonuclear leukocytes. The mucous membrane is anesthetized and had ulcerative defects. The patient was diagnosed with phlegmonous appendicitis, periappendicitis, diverticulitis.Vermiform process diverticulitis is not a common pathology, however a timely diagnosis can cause quite severe complications

Features of Chronic Bronchitis in Different Age Groups

Background: Lung diseases are assuming greater relevance and importance today. Chronic bronchitis is a self-nosology, which may precede the development of COPD, the importance of which can hardly be overestimated. The main problem in this disease is caused by late diagnosis and treatment due to the delay by patients in seeking medical help. The aim of the work was to study the distribution and exposure to tobacco smoke, especially chronic bronchitis, depending on various factors, including age. Methods: We examined 1779 persons, including 855 men and 924 women. The mean age of the population was 35.83±8.3 years. We conducted surveys and spirometry. The outcome was assessed after a bronchodilation test was performed with salbutamol 400 mcg. We performed all statistical analysis using software package Statistica 10. Results: We identified chronic bronchitis in 9.2% of the cases in the group of younger individuals and in 14.9% of the cases in the group of older individuals, during the active detection of chronic bronchitis using questionnaires. The prevalence of cigarette smoking was slightly higher among the younger (39.5%) than the older persons (33.6%); the frequency of smoking in a group of chronic bronchitis was reliably higher. Also, in this group, the performance spirometry reliably decreased. Conclusions: Outpatient survey is an effective method of identifying chronic bronchitis. Smoking is a major risk factor in the group of young respondents and the prevalence of smoking is inversely related to the education level of the respondents, regardless of age. As the decline in the Forced Expiratory Volume (FEV1 and FEV1/FVC) is the main criterion diagnosis of COPD, it revealed significant declines in the FEV1 of the younger smoking individuals, which may help to predict the development of COPD in the older age group

NUScon: a community-driven platform for quantitative evaluation of nonuniform sampling in NMR

Although the concepts of nonuniform sampling (NUS​​​​​​​) and non-Fourier spectral reconstruction in multidimensional NMR began to emerge 4 decades ago (Bodenhausen and Ernst, 1981; Barna and Laue, 1987), it is only relatively recently that NUS has become more commonplace. Advantages of NUS include the ability to tailor experiments to reduce data collection time and to improve spectral quality, whether through detection of closely spaced peaks (i.e., “resolution”) or peaks of weak intensity (i.e., “sensitivity”). Wider adoption of these methods is the result of improvements in computational performance, a growing abundance and flexibility of software, support from NMR spectrometer vendors, and the increased data sampling demands imposed by higher magnetic fields. However, the identification of best practices still remains a significant and unmet challenge. Unlike the discrete Fourier transform, non-Fourier methods used to reconstruct spectra from NUS data are nonlinear, depend on the complexity and nature of the signals, and lack quantitative or formal theory describing their performance. Seemingly subtle algorithmic differences may lead to significant variabilities in spectral qualities and artifacts. A community-based critical assessment of NUS challenge problems has been initiated, called the “Nonuniform Sampling Contest” (NUScon), with the objective of determining best practices for processing and analyzing NUS experiments. We address this objective by constructing challenges from NMR experiments that we inject with synthetic signals, and we process these challenges using workflows submitted by the community. In the initial rounds of NUScon our aim is to establish objective criteria for evaluating the quality of spectral reconstructions. We present here a software package for performing the quantitative analyses, and we present the results from the first two rounds of NUScon. We discuss the challenges that remain and present a roadmap for continued community-driven development with the ultimate aim of providing best practices in this rapidly evolving field. The NUScon software package and all data from evaluating the challenge problems are hosted on the NMRbox platform