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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">sibmed</journal-id><journal-title-group><journal-title xml:lang="ru">Сибирский научный медицинский журнал</journal-title><trans-title-group xml:lang="en"><trans-title>Сибирский научный медицинский журнал</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2410-2512</issn><issn pub-type="epub">2410-2520</issn><publisher><publisher-name>ИЦиГ СО РАН</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.18699/SSMJ20240307</article-id><article-id custom-type="elpub" pub-id-type="custom">sibmed-1548</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>АНАТОМИЯ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ANATOMY</subject></subj-group></article-categories><title-group><article-title>Макромикроскопическая анатомия и гистотопография стенок левого ушка сердца плода человека</article-title><trans-title-group xml:lang="en"><trans-title>Mesoscopic anatomy and histotopography of the left atrial appendage walls in human fetal heart</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6681-7537</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Гапонов</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Gaponov</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Гапонов Антон Александрович</p><p>620002, г. Екатеринбург, ул. Мира, 19;</p><p>620028, г. Екатеринбург, ул. Репина, 3</p></bio><bio xml:lang="en"><p>Anton A. Gaponov</p><p>620002, Ekaterinburg, Mira st., 19;</p><p>620028, Ekaterinburg, Repina st., 3</p></bio><email xlink:type="simple">gagaponov@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0001-4594-1221</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Уфимцева</surname><given-names>И. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Ufimtseva</surname><given-names>I. D.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Уфимцева Илана Дмитриевна</p><p>620002, г. Екатеринбург, ул. Мира, 19</p></bio><bio xml:lang="en"><p>Ilana D. Ufimtseva</p><p>620002, Ekaterinburg, Mira st., 19</p></bio><email xlink:type="simple">ufimtsevailana20@gmail.com</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2973-3481</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Дмитриева</surname><given-names>Е. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Dmitrieva</surname><given-names>E. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Дмитриева Евгения Германовна</p><p>620002, г. Екатеринбург, ул. Мира, 19;</p><p>620028, г. Екатеринбург, ул. Репина, 3</p></bio><bio xml:lang="en"><p>Evgenia G. Dmitrieva</p><p>620002, Ekaterinburg, Mira st., 19;</p><p>620028, Ekaterinburg, Repina st., 3</p></bio><email xlink:type="simple">anmayak@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5133-3962</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кузнецов</surname><given-names>Д. К.</given-names></name><name name-style="western" xml:lang="en"><surname>Kuznetsov</surname><given-names>D. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кузнецов Дмитрий Константинович, к.ф.-м.н.</p><p>620002, г. Екатеринбург, ул. Мира, 19</p></bio><bio xml:lang="en"><p>Dmitrii K. Kuznetsov, candidate of physical and mathematical sciences</p><p>620002, Ekaterinburg, Mira st., 19</p></bio><email xlink:type="simple">dimak@urfu.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7001-051X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Пряхина</surname><given-names>В. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Pryakhina</surname><given-names>V. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Пряхина Виктория Игоревна, к.ф.-м.н.</p><p>620002, г. Екатеринбург, ул. Мира, 19</p></bio><bio xml:lang="en"><p>Victoria I. Pryakhina, candidate of physical and mathematical sciences</p><p>620002, Ekaterinburg, Mira st., 19</p></bio><email xlink:type="simple">viktoria.pryahina@urfu.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8267-2895</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Якимов</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Iakimov</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Якимов Андрей Аркадьевич, к.м.н.</p><p>620002, г. Екатеринбург, ул. Мира, 19;</p><p>620028, г. Екатеринбург, ул. Репина, 3</p></bio><bio xml:lang="en"><p>Andrei A. Iakimov, candidate of medical sciences</p><p>620002, Ekaterinburg, Mira st., 19;</p><p>620028, Ekaterinburg, Repina st., 3</p></bio><email xlink:type="simple">ayakimov07@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Уральский Федеральный университет имени первого Президента России Б.Н. Ельцина;&#13;
Уральский государственный медицинский университет Минздрава России<country>Россия</country></aff><aff xml:lang="en">Ural Federal University named after the first President of Russia B.N. Yeltsin;&#13;
The Ural State Medical University of Minzdrav of Russia<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Уральский Федеральный университет имени первого Президента России Б.Н. Ельцина<country>Россия</country></aff><aff xml:lang="en">Ural Federal University named after the first President of Russia B.N. Yeltsin<country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>03</day><month>07</month><year>2024</year></pub-date><volume>44</volume><issue>3</issue><fpage>68</fpage><lpage>77</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Гапонов А.А., Уфимцева И.Д., Дмитриева Е.Г., Кузнецов Д.К., Пряхина В.И., Якимов А.А., 2024</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Гапонов А.А., Уфимцева И.Д., Дмитриева Е.Г., Кузнецов Д.К., Пряхина В.И., Якимов А.А.</copyright-holder><copyright-holder xml:lang="en">Gaponov A.A., Ufimtseva I.D., Dmitrieva E.G., Kuznetsov D.K., Pryakhina V.I., Iakimov A.A.</copyright-holder><license license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://sibmed.elpub.ru/jour/article/view/1548">https://sibmed.elpub.ru/jour/article/view/1548</self-uri><abstract><p>Данные о строении стенок левого ушка сердца (ЛУС) плода человека актуальны в связи с развитием фетальной кардиохирургии и биопечати сердца. Цель исследования – определить особенности макромикроскопической анатомии и гистотопографии разных отделов стенок левого ушка нормального сердца человека 16–22 недель внутриутробного развития. Материал и методы. При помощи микроскопа Olympus CX, камеры TOUPCAM U31S, программы ADF-Image изучили окрашенные орсеином, зеленым прочным и по Массону серийные гистотопографические срезы левого предсердия и ЛУС 10 сердец плодов человека. При помощи сканирующего электронного микроскопа Carl Zeiss EVO LS 10 при увеличении в 15–5000 раз исследовали три образца по методу замораживания-скалывания. Результаты. При морфометрии стенок межтрабекулярных пространств ЛУС установлено, что на уровне средней трети левого предсердия их толщина минимальна в задней стенке (80 [61–97] мкм) (медиана [нижняя квартиль; верхняя квартиль]), толщина в передней стенке составляет 142,9 ± 33,2 мкм (среднее ± стандартное отклонение) (101 [79–192] мкм). На уровне венечной борозды толщина передней стенки равна 137,4 ± 33,9 мкм (101 [68–195] мкм), задней стенки – 143,7 ± 23,6 мкм (147,5 [90–180] мкм). В направлении сверху вниз толщина передней стенки ЛУС не изменялась, толщина задней стенки возрастала в среднем в 1,8 раза за счет утолщения миокарда. Толщина эндокарда во всех изученных локализациях одинакова. Миокард ЛУС на макромикроанатомическом уровне организован в виде «анатомического синцития», иногда формировал отдельные пучки. Слои коллагеновых и эластических волокон характерны для эндокарда, реже для эпикарда. Из-за проникновения эластических волокон в подлежащий коллагеновый слой граница между ними условна. Заключение. Макромикроанатомические особенности стенок ЛУС плода человека состоят в различиях их толщины на разных уровнях, организации миокарда как «анатомического синцития» с возможным формированием пучков, в отсутствии слоев миокарда, существовании безмышечных и гипомускулярных участков, а также в послойном расположении эластических и коллагеновых волокон в эндокарде без четкой границы между этими слоями.</p></abstract><trans-abstract xml:lang="en"><p>Normal anatomy of the left atrial appendage (LAA) of human fetus is of a great importance for fetal cardiac surgery and heart bioprinting. Aim of the study was to clarify the mesoscopic anatomy and histotopography of different parts of the LAA walls in normal human fetuses of 16–22 gestation weeks. Material and methods. We prepared serial histotopograms of the left atrial appendages from 10 normal human fetal hearts stained by Masson trichrome, orcein and fast green. We studied slides by means Olympus CX microscope, TOUPCAM U31S digital camera, and ADF-Image program for measuring. Using a Carl Zeiss EVO LS 10 scanning electron microscope at a magnification of 15–5000 times, three samples were examined using the freeze-chip method. Results. Having measured the outer walls of the LAA intertrabecular spaces, we found that at the level of the middle third of the left atrium, their thickness is minimal in the posterior wall (80 [61–97] μm) (median [lower quartile; upper quartile]), thickness in the anterior wall is 142.9 ± 33.2 μm (mean ± standard deviation) (101 [79–192] μm). At the level of the coronary sulcus, the same parameters were 143.7 ± 23.6 µm (147.5 [90–180] µm) and 137.4 ± 33.9 µm (101 [68–195] µm), respectively. Downward, LAA posterior wall increased about 1.8 in thickness, whereas the thickness of the anterior wall was the same. The endocardium showed the same thickness in all locations. Microanatomically, the LAA myocardium never discovered to build from distinct layers but “anatomical syncytium” or seldom bundles. Collagen and elastic layers were common for endocardium, rare for epicardium. Endocardial elastic fibers interweaved in the underlying collagen so the distinct boundary lacks there. Conclusions. Mesoscopic and microanatomical features of LAA walls in human fetus consist of variable thickness at different levels, unlayered but “syncytial” myocardium, muscleless areas, elastic and collagen layers of the endocardium.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>анатомия человека</kwd><kwd>анатомия сердца</kwd><kwd>плод человека</kwd><kwd>предсердия</kwd><kwd>ушки сердца</kwd><kwd>миокард</kwd><kwd>эндокард</kwd><kwd>рыхлая соединительная ткань сердца</kwd></kwd-group><kwd-group xml:lang="en"><kwd>human anatomy</kwd><kwd>heart anatomy</kwd><kwd>human fetus</kwd><kwd>atria</kwd><kwd>atrial auricles</kwd><kwd>atrial appendages</kwd><kwd>myocardium</kwd><kwd>endocardium</kwd><kwd>loose connective tissue of the heart</kwd></kwd-group><funding-group xml:lang="ru"><funding-statement>Работа выполнена с использованием оборудования анатомо-физиологической лаборатории департамента биологии и фундаментальной медицины, лаборатории кафедры медицинской биохимии и биофизики Института естественных наук и математики Уральского Федерального университета, а также УЦКП «Современные нанотехнологии» Уральского Федерального университета (рег. № 2968), поддержанным Минобрнауки РФ (проект 075-15-2021-677).</funding-statement></funding-group><funding-group xml:lang="en"><funding-statement>The work was carried out using the equipment of the anatomical and physiological laboratory of the Department of Biology and Fundamental Medicine, the laboratory of the Department of Medical Biochemistry and Biophysics of the Institute of Natural Sciences and Mathematics of Ural Federal University, as well as the Ural CCU “Modern Nanotechnologies” of Ural Federal University (reg. 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