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Preliminary results on the ovarian histology of rabbitfish Siganus rivulatus (Forsskal, 1775) in the southern Aegean Sea, Turkey

Engin Serha, Soykan Ozan, Cerim Hasan, Gülşahin Anıl

Oceanological and Hydrobiological Studies

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2020

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Vol. 49, No. 3

207--214

EN

The study aimed to determine the annual reproductive cycle of Siganus rivulatusfi females based on monthly variation of the gonadosomatic index (GSI) and histological changes in gonads. A total of 240 fish samples were collected monthly from small-scale (trammel nets) and recreational (angling and pot fishery) fishing from Gökova Bay, the southern Aegean Sea, between July 2017 and June 2018. The length and weight of female fish varied from 10.8 to 26.1 cm with a mean length of 18.7 ± 0.2 cm and from 14.98 to 293.42 g with a mean weight of 91.1 ± 2.93 g. GSI values began to increase in May, peaked in June and gradually decreased in July, indicating that the spawning season was early summer. A total of 240 gonads were histologically examined. Granular, pinkish structure of eggs was observed primarily between April and June, which was consistent with the increase in the gonadosomatic index. Post-spawning follicles were determined in July. Values of the gonadosomatic index gradually decreased after August and they were minimal between September and November. During this period, ovaries were surrounded by immature oocytes at the chromatin and peri-nucleolus stages. These results revealed that Siganus rivulatusstarted vitellogenesis in April and the gonadosomatic index peaked in June.

2

The interaction of laser radiation with tissue in the aspect of generating the process of decellularization in the preparation of animal origin autologous tissue

Kopernik Magdalena, Major Roman, Lis Grzegorz, Wilczek Piotr, Lis Maciej, Imbir Gabriela, Chrouda Abir, Mzyk Aldona, Ostrowski Roman, Sanak Marek

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 1

67--77

EN

Purpose: The aim of the work was to create an appropriate substrate for organ transplantation using bioactive tissue-based scaffold populated by cells of the graft recipient. The purpose of the modeling was to investigate the mechanical effects of wave loading of aortic and pulmonary tissue material. Methods: The biological properties of tissues of aortic and pulmonary valves were modified by the process of decellularization. The host cells were removed by various physical methods with focus on minimal degradation of the extracellular matrix. Thus, the decellularization process was controlled by histological methods. The tissue decellularization process was simulated by finite element modelling. Results: The mechanical results represented by a displacement at the center of the sample were coherent and the heterogeneity of the distribution of the caves on the surface of the samples was confirmed, both by experiment and in the simulation by the alternate occurrence of local minima and maxima. The latter results from the uneven removal of cells from the effect of the wave causing decellularization were also predicted by the numerical model. Laser radiation had a destructive effect on the components of the extracellular matrix (e.g., collagen and elastic fibers), mainly depending on the fluence and number of pulses in a single exposure. Conclusions: The differences between the valve tissue materials were shown, and the impact of the process of decellularization on the properties of the tissues was analyzed. It should be emphasized that due to low absorption and high scattering, laser radiation can deeply penetrate the tissue, which allows for effective decellularization process in the entire volume of irradiated tissue.

3

Changes in the mechanical properties of femoral cartilage tissue in advanced osteoarthritis

Dragan Szymon Ł., Kuropka Piotr, Kulej Mirosław, Gabryś Piotr, Nikodem Anna

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 1

143--152

EN

The main goal of this article was the analysis of the changes of mechanical properties, thickness and histology of the cartilage in different regions of the femur head in advanced stage of the osteoarthritis. Methods: The study material consisted of cylindrical specimens (9.7 mm) prepared form proximal epiphysis of the human femur bone after hip arthroplasty. The thickness was determined from the reconstruction of the specimen from microtomography (SkyScan 1172, Bruker®) images. Mechanical properties of the cartilage tissue were identified in static indentation test conducted the use of MTS® Synergie 100 testing machine. Histological study enabled us to determine cartilage total thickness as well as location and orientation of the collagen fibers. Results: Depending on the region of the head, the cartilage tissue thickness was in the range (0.74–2.23 mm). The lowest thickness values were obtained for the R5 region and the lowest for R4. Samples from R1–R4 regions differ by 24%. Measurements of cartilage tissue indentation, determined with the help of Hayes’ formula, showed that the values of mechanical parameters in regions R1, R2, R3 and R5 have similar values (the difference between them is about 5.5%). Region R4, which had the smallest thickness, also had the lowest values of mechanical parameters. Conclusions: Using κ coefficients, proposed by Hayes, enabled us to obtain similar values of mechanical parameters in the regions R1, R2, R3 and R5, despite differences in cartilage tissue thickness. The R4 region, which had the weakest mechanical parameters, was characterized by the strongest reduction of the articular cartilage tissue, which was accompanied by an unformed mass of cartilage residue originating from the abraded surface and bursa fluid.

4

Use of optical microscopy for evaluation of tooth structure

Banaszek K., Sawicki J., Wołowiec-Korecka E., Gorzędowski J., Danowska-Klonowska D., Sokołowski J.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 79, nr 1

31--40

EN

Purpose: There are many methods of examining tooth anatomy: some of them are applicable to the hard tissues, while others to the pulp and the root canal system. Every method has some advantages and disadvantages in terms of revealing specific anatomical or histological details of the tooth. The objective of the present work was to assess the use of macroscopic microscopy for evaluation of tooth anatomy and to compare the obtained images with those produced by the radiovisiographic method. Design/methodology/approach: The study involved 4 upper canines extracted for periodontal reasons from patients of different age and sex. Initially, radiological images were taken in the vestibular-lingual and lateral projections by the radiovisiographic method using a KODAK 2000 system with a KODAK 6100 sensor. Subsequently, the specimens were ground with sandpaper and consecutive dental cross-sections were captured at approximately 0.05 mm increments using a NIKON AZ100 multizoom microscope. Findings: The presented method, using side illumination and a digital capture device transferring the images to a computer, enables evaluation of tooth anatomy in terms of both shape and internal structure, and offers the dimensioning functionality. Practical implications: Optical microscopy is a cheap method of examining the hard tissues of the tooth, including restorative materials, and for evaluating the development of primary and secondary dentin, as well as dentin affected by bacterial infection. A microscope used in conjunction with good software provides many opportunities for easy examination and dimensioning of particular anatomical features of the tooth on consecutive planes. Originality/value: This is an honest methods review and analysis which are applied in modern prosthetics.

5

Determination of the mechanical properties of the skin of pig foetuses with respect to its structure

Żak M., Kuropka P., Kobielarz M., Dudek A., Kaleta-Kuratewicz K., Szotek S.

Acta of Bioengineering and Biomechanics

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2011

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Vol. 13, no. 2

37-43

EN

Skin is an important barrier protecting the organism against external environmental factors. Determination of its mechanical characteristics as regards its structure has significant scientific and application value. In this work, uniaxial tensile tests were conducted to determine the basic mechanical parameters of skin with respect to its structure. The subject of the study were skin samples taken from domestic pig foetuses. They were excised from different parts of body, in the direction parallel to the long axis of the body. Regardless of the sampling site, the tests revealed no significant differences in the values of the maximum tensile strength (2.08 +- 0.25 MPa) and the conventional Young's modulus (5.87 +- 1.52 MPa). The mechanical and structural tests confirmed that regardless of the sampling region the skin of domestic pig foetuses may constitute a human skin substitute model.

6

Structure of long bones in small terrestrial mammals from different types of environment

Martiniakova M., Omelka R., Grosskopf B., Jančova A., Boleček P., Vondrakova M., Bauerova M.

Chemia i Inżynieria Ekologiczna

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2006

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Vol. 13, nr 7

669-674

EN

Bone development and its resulting structure are influenced by both genetic and environmental factors. In the present study the structure of long bones taken from small terrestrial mammals living in different biotopes of hillock level (relatively clean region - Nitra and polluted region - Novaky with high accumulation of As, Cd, Cu and Pb) was investigated. Altogether 30 and 26 femora of adult yellow-necked mouse (Apodemus flavicollis) and adult bank vole (Cleithrionomys glareolus) were analysed, respectively. We compared bone length, bone weight and histological structure of the bones between investigated animals from different types of environment. According to our results the measured values for bone length and bone weight were higher in small terrestrial mammals living in polluted environment. The differences were statistically significant (p < 0.01; p< 0.001). Histological observation of thin sections through a shaft of femora from .Apodemus flavicollis and Cleithrionomys glareolus revealed an outer and inner essentially non-vascular lamellar layer around a poorly developed reticular layer, containing unorganized vascular canals. We did not identify changes in qualitative histological characteristics of the bones between animals from different biotopes. Our results indicate that environmental factors (including chemical elements in the environment) influence the macroscopic structure of the femora in small terrestrial mammals; however, genetics plays a substantial role in the variability of bone microstructure between the animals against the background of enviromnental factors.

PL

Rozwój kości i kształtowanie ich struktury dokonuje się zarówno pod wpływem czynników genetycznych, jak i środowiskowych. Celem badań było określenie struktury kości długich małych ssaków ziemnych żyjących biotopach o zróżnicowanym stopniu zanieczyszczenia metalami ciężkimi (ssaki odławiano na stosunkowo mało zanieczyszczonym pagórkowatym rejonie miasta Nitra oraz na wzgórzach w okolicy miejscowości Novaky charakteryzujących się dużą akumulacją arsenu, kadmu, miedzi i ołowiu). Do badań pobrano 30 kości udowych dojrzałych osobników myszy leśnej (Apodemus flavicollis) i 26 kości udowych dojrzałych osobników nornicy rudej (Cleithrionomys glareolus). Określono długość i masę kości oraz ich strukturę histologiczną. Stwierdzono istnienie statystycznie istotnych różnic pomiędzy zwierzętami żyjącymi w dwóch różnych środowiskach. Długość kości i ich masa były większe u zwierząt żyjących w środowisku zanieczyszczonym metalami ciężkimi (p < 0.01; p< 0.001). W badaniach histologicznych cienkich skrawków wykonanych z trzonu kości udowej Apodemus flavicollis i Cleithrionomys glareolus stwierdzono istnienie zewnętrznej i wewnętrznej nieunaczynionej blaszkowatej warstwy wokół słabo rozwiniętej warstwy siatkowatej, zawierającej nieuorganizowane kanały naczyniowe. Nie dostrzeżono zmian jakościowych w strukturze histologicznej kości pomiędzy zwierzętami zasiedlającymi różne biotopy. Uzyskane wyniki badań wskazują, ze czynniki środowiskowe (a wśród nich związki chemiczne i jony metali ciężkich) mają wpływ na strukturę makroskopową kości udowej u małych ssaków ziemnych, zaś czynniki genetyczne są odpowiedzialne za istnienie zróżnicowania w strukturze histologicznej kości.

7

Noding in Cyprideis torosa and its causes

Keyser D., Aladin N.

Studia Quaternaria

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2004

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Vol. 21

19-24

EN

The Ostracod Cyprideis torosa develops nodes on its calcified carapace in brackish waters and is therefore widely used in paleontology as a marker for lower saline waters. The formation of nodes in lower saline waters was investigated with SEM and TEM analyses and micro-cryoscopic measurements of the inner osmoregulation. Noding is considered a failure in osmoregulation, which causes the pillars connecting the inner and outer epidermal cell layer to rupture during the molting process. As a result, the still flexible shell develops protrusions, which then persist as nodes after subsequent calcification.

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Wpływ promieniowania ultrafioletowego i światła widzialnego na strukturę tkanki osierdzia świni

Cwalina B., Turek A., Nożyński J., Jastrzębska M.

Inżynieria Biomateriałów

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2003

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R. 6, nr 30-33

85-88

PL

Analizowano wpływ promieniowania ultrafioletowego (UV) i światła widzialnego (VIS) na strukturę tkanek osierdzia świńskiego, wykorzystując badania profili elektroforetycznych białek uwalnianych z tkanek i histologiczne badania struktury tkanek. Wykazano, że tkanki osierdzia poddane naświetlaniu UV lub VIS w czasie 1 h lub dłuższym mogą ulegać procesowi fotodegradacji.

EN

Analyzed was an effect of ultraviolet radiation (UV) and visible light (VIS) on structure of porcine pericardium tissue, by means of investigations of eletrophoretic profiles of proteins extracted from tissue structure. It has been demonstrated that the pericardium tissues treated with UV or VIS-radiation for 1 h or longer may undergo the photodegradation process.

9

Wpływ antybiotyków na strukturę tkanki osierdzia świni

Turek A., Cwalina B., Pawlus-Łachecka L., Nożyński J.

Inżynieria Biomateriałów

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2002

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R. 5, nr 23-25

57-61

PL

Badano zmiany struktury tkanek osierdzia świni: natywnych i modyfikowanych za pomocą kwasu taninowego (TA), pod wpływem roztworu antybiotyków, stosowanego do przechowywania implantów tkankowych. Stwierdzono, że antybiotyki powodowały zwiększenie stabilności biochemicznej i strukturalnej tkanek osierdzia - zarówno natywnej, jak i modyfikowanej za pomocą TA. Wzrost stabilności biochemicznej odzwierciedlał się w mniejszej ilości białek niskocząsteczkowych ekstrahowanych z tkanek poddanych działaniu antybiotyków. Wyniki te sugerują również, że antybiotyki mogą uczestniczyć w sieciowaniu tkanki osierdzia. Badania histologiczne wykazały stabilność struktury tkanek poddanych działaniu antybiotyków.

EN

Investigated were changes in structure of porcine pericardium tissues: native and modified by means of tannic acid (TA), under the influence of antibiotics solution used for storage of tissue implants. It has been found that antibiotics caused increase in biochemical and structural stability of pericardium tissues - both native and modified by means of TA. Growth in biomechanical stability was reflected smaller amounts of low-molecular proteins extracted from tissues treated with antibiotics. These results suggest also that antibiotics may participate in crosslinking of pericardium tissue. Histological investigations indicated stability of the tissues treated with antibiotics.