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2021 ◽  
Vol 25 (3 (99)) ◽  
pp. 89-96
Author(s):  
D. Proniaiev ◽  
I. Kashperuk-Karpiuk ◽  
V. Proniaiev ◽  
S. Riabyi

Aim. To determine macro-and microscopic anatomical characteristics and the dynamics in topographic and anatomical interactions of the bladder neck with adjacent organs and structures at the beginning of the fetal period. Material and methods. The study was carried out on 70 fetal specimens. The age of subjects included in the study was determined according to the tables of B.M. Patten, B.P. Khvatova, Yu.N. Shapovalov based on measurements of the parietal-calcaneal length (PCL), taking into account the Instructions for determining the perinatal period, live birth, and stillbirth criteria, approved by Order of the Ministry of Health of Ukraine No. 179 dated March 29, 2006. To achieve this goal, the following methods of anatomical research were used: anthropometry - to determine the age of the studied subjects; injection of arterial vessels with subsequent dissection under the control of a microscope – to study the peculiarities of the blood supply to the vesicoureteral segment; radiography - to determine the skeletotopy of the vesicoureteral segment; macro-microscopy – to explore the anatomical relationships of the components of the vesicoureteral segment, their structure, shape, position; histological – to study the structure of the wall of the vesicoureteral segment; morphometry – to determine the morphometric parameters of the vesicoureteral segment; 3-D reconstruction method – to study the spatial structure of the vesicoureteral segment; statistical – to analyze and establish the reliability of differences in organometric parameters.Results. Skeletopically, the projection of the vesicoureteral junction of early fetuses is located at the level of the upper third of the pubic symphysis. At the beginning of the perinatal period in female fetuses, the bladder neck (6.9 ± 2.6 mm) is longer than in male fetuses (6.4 ± 2.4 mm). Based on the analysis and generalization of the research results, it is substantiated that at the beginning of the fetal period, the internal urethral sphincter can be formed: a) by two loops of the outer longitudinal layer; b) the ring of the circular layer and the front bundles of the outer longitudinal layer; c) anterior bundles of the outer longitudinal layer and transverse bundles of the inner longitudinal layer within the trigone of urinary bladder; d) a ring of the circular layer, thickened in the anterolateral sections.Conclusions. Considering the topographic and anatomical characteristics of the angio- and myoarchitectonics of the vesicoureteral segment, we believe that its role as a physiological sphincter of the lower urinary tract is provided by the interaction of the vascular and muscle components. The vascular component of the sphincter apparatus of the vesicoureteral segment is provided by veins located in three layers: 1) cavernous-like veins of the submucosa; 2) veins of the muscular membrane; 3) veins of tunica adventitia. The second anatomical component of the sphincter function of the vesicoureteral segment is the muscular one, represented by the internal urethral sphincter.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
M. O. Agbugui ◽  
H. O. Egbo ◽  
F. E. Abhulimen

Background. The African bonytongue, Heterotis niloticus, is readily accommodated in the fresh water of the Niger River. It is available all year round with a large population of juveniles and adults due to its fast growth and versatile feeding habits. This commercial fish is a highly preferred source of food because of its high protein content and hardy flesh, thus forming a very important component in the diet of many Nigerians. It is highly valued because of its socioeconomic importance and benefits. Hence, this research is designed with the aim of studying the biology of the African bonytongue, Heterotis niloticus, and providing viable information about its importance in fish culture in order to make an available added variety of culturable and affordable fish species in Nigeria. Results. The oesophagus is a muscular organ that is short and distensible. The oesophagus leads to the gizzard-like stomach, a reddish bilobed organ that is muscular and tough. H. niloticus is an omnivorous macrophage detritor, consuming a wide variety of bottom-dwelling food items. The histology of the gastrointestinal tract reveals four conspicuous layers from the inside to the outside: mucosa, submucosa, inner circular layer and outer longitudinal layer of muscularis, and serosa. The presence of numerous mucus glands and longitudinal folds with a prominent columnar epithelium provides durable length or an extension of the gut mucus to aid lubrication and easy passage of food materials, protecting the mucosal epithelium from mechanical or chemical injuries arising from interactions with digestive tract contents or enzymes. In addition, the presence of absorptive cells helps in the absorption of valuable nutritive substances. Conclusions. The anatomy of the mouth and gut and the aforementioned histology are modified to accommodate the feeding habits. H. niloticus has a single ovary that rests on the right side of the fish; it is reproductively active as the flood plains rise and peaks at the peak of the rains, being a moderately fecund fish. The high fecundity is complemented with peaks of GSI observed during the months of September, October, and November, which reveals spawning periods. Hence, the aforementioned attributes of H. niloticus make the fish a viable fish species for culture.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mi-Sun Hur ◽  
Seunggyu Lee ◽  
Tong Mook Kang ◽  
Chang-Seok Oh

AbstractThis study was conducted to determine the muscular arrangement of the human pyloric sphincter using a comprehensive approach that involved microdissection, histology, and microcomputed tomography (micro‐CT). The stomachs of 80 embalmed Korean adult cadavers were obtained. In all specimens, loose muscular tissue of the innermost aspect of the sphincter wall ran aborally, forming the newly found inner longitudinal muscle bundles, entered the duodenum, and connected with the nearby circular bundles. In all specimens, approximately one-third of the outer longitudinal layer of the sphincter entered its inner circular layer, divided the circular layer into several parts, and finally connected with the circular bundles. Anatomical findings around the sphincter were confirmed in micro-CT images. The sphincter wall comprised three layers: an inner layer of longitudinal bundles, a middle layer of major circular and minor longitudinal bundles, and an outer layer of longitudinal bundles. The stomach outer longitudinal bundles were connected to the sphincter circular bundles. The inner longitudinal bundles of the sphincter were connected to the adjacent circular bundles of the duodenum.


PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0252438
Author(s):  
Aleksandra Zygmuntowicz ◽  
Włodzimierz Markiewicz ◽  
Tomasz Grabowski ◽  
Artur Burmańczuk ◽  
Alla Vyniarska ◽  
...  

Quercetin is a polyphenolic flavonoid occurring in leaves, stems, flowers and fruits of many plants. In traditional Chinese medicine, it is used as a natural therapeutic agent with a broad spectrum of activities (antioxidant, neuroprotective, anti-inflammatory, anticancer, antibacterial and antiviral). Moreover, quercetin affects function of the reproductive tract, however the knowledge of this activity is still fragmentary. Therefore, this study aimed to determine the influence of quercetin on the contractile activity of the porcine myometrium collected from immature (n = 6), cyclic (n = 6) and early pregnant (n = 6) gilts. Strips of the myometrium (comprising longitudinal and circular layer) were resected from the middle part of the uterine horns and the isometric contractions were recorded. After 60–90 min of preincubation, the strips were stimulated with quercetin in increasing (10−13–10−1 M) concentrations and the changes in the tension amplitude and frequency of contractions were measured. Quercetin decreased (P<0.01–0.001) the amplitude of contractions at concentrations 10−11–10−1 M and 10−10–10−1 M in cyclic and early pregnant groups, respectively. The frequency of contractions decreased in all groups but was the highest (at concentrations 10−11–10−1 M; P<0.05–0.001) in the cyclic group and the lowest (at concentrations 10−5–10−1 M; P<0.01) in the immature group. The tension decreased only in the cyclic group after quercetin administration in high concentrations (10−6–10−1 M; P<0.05–0.01). The results indicate that quercetin causes relaxation of the porcine uterine smooth muscle but this activity is strongly related to the physiological status of the gilts.


Author(s):  
Lea Magdalena Rempel ◽  
Karina Tietgen Andresen Lillevang ◽  
Ann-Kirstine thor Straten ◽  
Sólrún Barbara Friðriksdóttir ◽  
Hanna Körber ◽  
...  

AbstractThe aetiology of primary uterine inertia (PUI), which is the most common cause of canine dystocia, is still not elucidated. Prostaglandins (PGs) play a crucial role in parturition. We hypothesized that the expression of prostaglandin endoperoxidase synthase 2 (PTGS2), PGF2α synthase (PGFS), and corresponding receptor (PTGFR) is altered in PUI. We investigated PTGS2, PGFS, and PTGFR mRNA expression, and PTGS2 and PGFS protein expression in interplacental (IP) and uteroplacental sites (UP) in bitches with PUI, obstructive dystocia (OD), and prepartum (PC). PTGS2, PGFS, and PTGFR mRNA expression did not differ significantly between PUI and OD (IP/UP). PTGFR ratio in UP was higher in PC than in OD (p = 0.014). PTGS2 immunopositivity was noted in foetal trophoblasts, luminal and superficial glandular epithelial cells, smooth muscle cells of both myometrial layers, and weakly and sporadically in deep uterine glands. PGFS was localized in luminal epithelial cells and in the epithelium of superficial uterine glands. PTGS2 and PGFS staining was similar between PUI and OD, while PGFS protein expression differed between OD and PC (p = 0.0215). For PTGS2, the longitudinal myometrial layer of IP stained significantly stronger than the circular layer, independent of groups. These results do not support a role for PTGS2, PGFS, and PTGFR in PUI. Reduced PGFS expression in IP during parturition compared with PC and the overall lack of placental PGFS expression confirm that PGFS is not the main source of prepartal PGF2alpha increase. The difference in PTGS2 expression between IP myometrial layers warrants further investigation into its physiological relevance.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Soha A. Soliman ◽  
Fatma A. Madkour

AbstractThe current study focused on the histogenesis of the esophagus in quail embryos. Formation of the gut tube occurred on the 4th day of incubation. Development of the muscular layers occurred in a sequential manner; the inner circular layer on the 7th day, the outer longitudinal layer on the 8th day and the muscularis mucosae on the 9th day. Glandular development began on the 13th day of incubation. The epithelium was pseudostratified columnar that consisted of mucous cells, dendritic cells, and keratinocyte precursors. Epithelial stratification occurred on the 15th day of incubation. We used Mallory trichrome, Weigert-Van Gieson, and Gomori silver stains to visualize fibrous components. Scanned samples showed formation of endoderm and mesoderm on the 5th day of incubation. A layer of myoblasts developed on the 8th day of incubation. Formation of mucosal folds, which contained glandular openings, occurred on the 14th to 17th days of incubation. On the 5th to 8th days of incubation, CD34 and vascular endothelial growth factor (VEGF) positive-mesodermal cells, and telocytes (TCs) were detected. On the 15th day of incubation, CD34 and VEGF positive-telocytes, and fibroblasts, were identified. The current study described the correlations between functional morphology and evolutionary biology.


2021 ◽  
Vol 09 (05) ◽  
pp. 901-919
Author(s):  
Ranis N. Ibragimov ◽  
Lauren D. Mongrain ◽  
Benjamin Stimmel ◽  
Olga Trozkaya ◽  
Guang Lin ◽  
...  

2020 ◽  
Vol 20 (9) ◽  
pp. 1494-1503
Author(s):  
Denize J.R. Dallagnol ◽  
Luciana A. Corá ◽  
Loyane A. Gama ◽  
Romero S. Caló ◽  
José R.A. Miranda ◽  
...  

Background: Triple immunosuppressive therapy is associated with several gastrointestinal disorders. The aim of this study was to investigate the effects induced by the triple immunosuppressive therapy on the gastrointestinal tract of rats. Methods: Male Wistar rats were randomly assigned into three experimental groups: Control: filtered water; TAC + MPS + PRED: treated with Tacrolimus plus Mycophenolate Sodium plus Prednisone; and CSA + AZA + PRED: treated with Cyclosporine plus Azathioprine plus Prednisone. The treatment was done for 14 days by gavage. Gastric emptying and contractility were evaluated by the Alternating Current Biosusceptometry (ACB) and Electrogastrography (EGG). Histological, biochemical and hematological analyses were also performed. Results: Gastric emptying time was slower in the CSA + AZA + PRED group in comparison with control (p<0.01) and TAC + MPS + PRED groups (p<0.001). Animals treated with TAC + MPS + PRED showed accelerated gastric emptying (p<0.05) compared to control. The amplitude of gastric contractions in both immunosuppressed groups was higher than observed in the control. The frequency of gastric contractions for the CSA + AZA + PRED group was also increased (p<0.01). Results obtained by EGG were similar to those recorded with the ACB. The thickness of the circular layer from stomach muscle decreased in both immunosuppressed groups, while the longitudinal layer was reduced only in the CSA + AZA + PRED group. Conclusion: Triple immunosuppressive therapy alters gastric motility, compromises the muscular layers


2019 ◽  
Vol 72 (3) ◽  
Author(s):  
Marta Dmitruk

Flowering and nectar release in <em>Acer pseudoplatanus</em> were investigated between 2011 and 2013. The micromorphology of the floral and nectary elements was observed using a scanning electron microscope and the anatomy of nectaries was examined by light microscopy. The inflorescence of the sycamore was found to contain flowers, which were functionally male or functionally female. The life-span of the former was on average 5 days, whereas the latter lived on average 4 days. Both types of <em>A. pseudoplatanus</em> flowers had yellow-green nectaries with a similar structure. The nectary tissue formed an elliptical or circular layer located on the receptacle surface between the petals and the pistil. The filament bases were located within the nectary recesses but were not fused with this organ. The nectary margins were slightly undulated. The outer diameter of the nectary was in 3.0–3.25 mm and the thickness of the nectary tissue was in the range of 532–1,023 μm. The nectary of the sycamore flower comprised a single layer of epidermal cells and several layers of secretory parenchyma cells. The average depth of epidermal cells was 16.8 μm. The stomata, which were involved in the secretion process, were arranged unevenly on the nectary surface and were surrounded by six–eight epidermal cells. Visible droplets of nectar accumulated on the nectary surface and thus they were easily accessible to insects. The average weight of nectar from 10 flowers was 16.54 mg (range: 11.0–23.75 mg) and the content of sugars in the nectar was found to be in the range of 23.5–50%, with an average of 37.3%. The calculated weight of sugars in the nectar from 10 flowers was on average 6.11 mg and so the average sugar yield from one sycamore tree was estimated to be 0.65 kg.


2019 ◽  
Vol 11 (17) ◽  
pp. 4766 ◽  
Author(s):  
Hanxiong Zhu ◽  
Kexi Pan ◽  
Yong Liu ◽  
Zheng Chang ◽  
Ping Jiang ◽  
...  

In this study, we create a high-resolution (1 km x 1 km) carbon emission spatially gridded dataset in Shanghai for 2010 to 2015 to help researchers understand the spatial pattern of urban CO2 emissions and facilitate exploration of their driving forces. First, we conclude that high spatial agglomeration, CO2 emissions centralized along the river and coastline, and a structure with three circular layers are the three notable temporal–spatial characteristics of Shanghai fossil fuel CO2 emissions. Second, we find that large point sources are the leading factors that shaped the temporal–spatial characteristics of Shanghai CO2 emission distributions. The changes of CO2 emissions in each grid during 2010–2015 indicate that the energy-controlling policies of large point emission sources have had positive effects on CO2 reduction since 2012. The changes suggest that targeted policies can have a disproportionate impact on urban emissions. Third, area sources bring more uncertainties to the forecasting of carbon emissions. We use the Geographical Detector method to identify these leading factors that influence CO2 emissions emitted from area sources. We find that Shanghai’s circular layer structure, population density, and population activity intensity are the leading factors. This result implied that urban planning has a large impact on the distribution of urban CO2 emissions. At last, we find that unbalanced development within the city will lead to different leading impact factors for each circular layer. Factors such as urban development intensity, traffic land, and industrial land have stronger power to determine CO2 emissions in the areas outside the Outer Ring, while factors such as population density and population activity intensity have stronger impacts in the other two inner areas. This research demonstrates the potential utility of high-resolution carbon emission data to advance the integration of urban planning for the reduction of urban CO2 emissions and provide information for policymakers to make targeted policies across different areas within the city.


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