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<article 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" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Kazan medical journal</journal-id><journal-title-group><journal-title xml:lang="en">Kazan medical journal</journal-title><trans-title-group xml:lang="ru"><trans-title>Казанский медицинский журнал</trans-title></trans-title-group></journal-title-group><issn publication-format="print">0368-4814</issn><issn publication-format="electronic">2587-9359</issn><publisher><publisher-name xml:lang="en">Eco-Vector</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">646022</article-id><article-id pub-id-type="doi">10.17816/KMJ646022</article-id><article-id pub-id-type="edn">HPECJK</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Theoretical and clinical medicine</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Теоретическая и клиническая медицина</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Potential of surface-enhanced Raman spectroscopy of blood serum in predicting mortality in patients undergoing maintenance hemodialysis</article-title><trans-title-group xml:lang="ru"><trans-title>Возможности поверхностно-усиленной рамановской спектроскопии сыворотки крови в оценке прогноза летальности у пациентов, получающих программный гемодиализ</trans-title></trans-title-group><trans-title-group xml:lang="zh"><trans-title>血清表面增强拉曼光谱在接受程序性血液透析患者死亡率预后评估中的可能性</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0002-2964-2675</contrib-id><contrib-id contrib-id-type="spin">2059-9769</contrib-id><name-alternatives><name xml:lang="en"><surname>Konovalova</surname><given-names>Daria Yu.</given-names></name><name xml:lang="ru"><surname>Коновалова</surname><given-names>Дарья Юрьевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>postgraduate student, Depart. of Therapy of the Institute of Professional Education with a course of functional diagnostics</p></bio><bio xml:lang="ru"><p>аспирант, каф. терапии Института профессионального образования с курсом функциональной диагностики</p></bio><email>snowflake0605@mail.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0703-2764</contrib-id><contrib-id contrib-id-type="spin">6774-6215</contrib-id><name-alternatives><name xml:lang="en"><surname>Skuratova</surname><given-names>Maria A.</given-names></name><name xml:lang="ru"><surname>Скуратова</surname><given-names>Мария Алексеевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Assistant Lecturer, Depart. of Therapy of the Institute of Professional Education with a course of functional diagnostics</p></bio><bio xml:lang="ru"><p>ассистент, каф. терапии Института профессионального образования с курсом функциональной диагностики</p></bio><email>skuratova_m@mail.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3501-2354</contrib-id><contrib-id contrib-id-type="spin">8085-3904</contrib-id><name-alternatives><name xml:lang="en"><surname>Lebedev</surname><given-names>Petr A.</given-names></name><name xml:lang="ru"><surname>Лебедев</surname><given-names>Пётр Алексеевич</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Dr. Sci. (Medicine), Professor, Head, Depart. of Therapy of the Institute of Professional Education with a course of functional diagnostics</p></bio><bio xml:lang="ru"><p>д-р мед. наук, профессор, заведующий, каф. терапии Института профессионального образования c курсом функциональной диагностики</p></bio><email>palebedev@yahoo.com</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0007-5185-0186</contrib-id><name-alternatives><name xml:lang="en"><surname>Pimenova</surname><given-names>Irina A.</given-names></name><name xml:lang="ru"><surname>Пименова</surname><given-names>Ирина Александровна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Master's student, Depart. of Laser and Biotechnical Systems</p></bio><bio xml:lang="ru"><p>магистрант, каф. лазерных и биотехнических систем</p></bio><email>pimenova.0312@list.ru</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0001-3768-9775</contrib-id><contrib-id contrib-id-type="spin">5945-6660</contrib-id><name-alternatives><name xml:lang="en"><surname>Biktogirova</surname><given-names>Regina I.</given-names></name><name xml:lang="ru"><surname>Биктогирова</surname><given-names>Регина Ильдусовна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Student; N.V. Sklifosovsky Institute of Clinical Medicine </p></bio><bio xml:lang="ru"><p>студент; Институт клинической медицины им. Н.В. Склифосовского </p></bio><email>biktogirovaregina@gmail.com</email><xref ref-type="aff" rid="aff3"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Samara State Medical University</institution></aff><aff><institution xml:lang="ru">Самарский государственный медицинский университет</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Samara National Research University</institution></aff><aff><institution xml:lang="ru">Самарский национальный исследовательский университет им. акад. С.П. Королёва</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">The First Sechenov Moscow State Medical University</institution></aff><aff><institution xml:lang="ru">Первый Московский государственный медицинский университет им. И.М. Сеченова</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2025-07-18" publication-format="electronic"><day>18</day><month>07</month><year>2025</year></pub-date><pub-date date-type="pub" iso-8601-date="2025-08-05" publication-format="electronic"><day>05</day><month>08</month><year>2025</year></pub-date><volume>106</volume><issue>4</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>553</fpage><lpage>562</lpage><history><date date-type="received" iso-8601-date="2025-01-12"><day>12</day><month>01</month><year>2025</year></date><date date-type="accepted" iso-8601-date="2025-04-23"><day>23</day><month>04</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Eco-Vector</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Эко-Вектор</copyright-statement><copyright-statement xml:lang="zh">Copyright ©; 2025,</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Eco-Vector</copyright-holder><copyright-holder xml:lang="ru">Эко-Вектор</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/" start_date="2028-08-05"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://eco-vector.com/for_authors.php#07</ali:license_ref></license></permissions><self-uri xlink:href="https://kazanmedjournal.ru/kazanmedj/article/view/646022">https://kazanmedjournal.ru/kazanmedj/article/view/646022</self-uri><abstract xml:lang="en"><p><bold>BACKGROUND:</bold> Predicting outcomes in chronic kidney disease remains challenging in modern medicine. It may be addressed using stratification systems based on biomarkers, including metabolic, electrolyte, inflammatory, and instrumental indicators.</p> <p><bold>AIM:</bold> This study aimed to assess the prognostic value of surface-enhanced Raman spectroscopy of blood serum in evaluating all-cause mortality in hemodialysis patients with end-stage chronic kidney disease.</p> <p><bold>METHODS:</bold> This prospective study included 58 patients of both sexes, aged 33–73 years (mean age: 57.0 ± 12.9 years) on maintenance hemodialysis. Over the 3-year follow-up, 13 deaths were recorded. An additional comparison group was formed, comprising 75 individuals (mean age: 51.33 ± 13.12 years; <italic>p</italic> &lt; 0.01) with estimated glomerular filtration rate corresponding to chronic kidney disease stages I–IIIa, to identify spectral characteristics associated with the mortality phenotype. According to current criteria, chronic kidney disease is diagnosed based on persistent signs of renal dysfunction, including a specific estimated glomerular filtration rate level, present for ≥3 months. However, the duration of asymptomatic stages of chronic kidney disease cannot be determined. Multivariate analysis was used to evaluate the statistical association between serum spectral characteristics and survival in 26 hemodialysis patients. To develop the prognostic model, least squares discriminant analysis was applied, which is a machine learning technique used for classification.</p> <p><bold>RESULTS:</bold> Data of the cohort of patients undergoing maintenance hemodialysis was analyzed: 13 individuals who died within 3 years following blood sampling and 5 groups of 13 individuals each, randomly selected from the remaining 45. Each group was formed independently. The model was tested over five iterations and the results averaged. The most prognostically significant spectral peaks were 731, 839, 1240, 1391, and 1578 cm<sup>-1</sup>. The model demonstrated an 83% sensitivity, 79% specificity, and 81% accuracy and an area under the ROC curve of 0.86. Notably, two of the five frequencies significant for survival prediction overlapped with those characteristic of creatinine and urea (637, 724, 1001, 1095, 1238, and 1393 cm<sup>−1</sup>), which enable differentiation between stages I–IIIa of chronic kidney disease and end-stage renal disease, yielding a 71% sensitivity, 95% specificity, and 83% overall accuracy.</p> <p><bold>CONCLUSION:</bold> Combined surface-enhanced Raman spectroscopy of blood serum and mathematical modeling presents high predictive accuracy with minimal labor input.</p></abstract><trans-abstract xml:lang="ru"><p><bold>Актуальность.</bold> Прогнозирование исходов хронической болезни почек представляет собой актуальную задачу современной медицины. Решение этой задачи возможно с помощью систем стратификации, основанных на биомаркерах, к которым относятся метаболические, электролитные, воспалительные и инструментальные показатели.</p> <p><bold>Цель.</bold> Определить прогностическую значимость поверхностно-усиленной рамановской спектроскопии сыворотки крови в оценке общей смертности у пациентов с терминальной хронической болезнью почек, находящихся на программном гемодиализе.</p> <p><bold>Материал и методы.</bold> В проспективное наблюдение включены 58 пациентов обоего пола в возрасте 33–73 лет (средний возраст — 57,0±12,9 года), находящиеся на программном гемодиализе. В течение 3 лет наблюдения зарегистрировано 13 летальных исходов. Для идентификации спектральных характеристик, имеющих значение для выделения фенотипа, связанного с летальностью, дополнительно сформирована группа сравнения из 75 обследованных (средний возраст — 51,33±13,12 года, <italic>р</italic> &lt;0,01) с расчётной скоростью клубочковой фильтрации, соответствующей стадиям хронической болезни почек от I до IIIа включительно. Согласно современным критериям, диагноз хронической болезни почек устанавливается при наличии признаков почечной дисфункции, включая ту или иную расчётную скорость клубочковой фильтрации, сохраняющихся в течение 3 мес и более. Однако точную продолжительность бессимптомных стадий хронической болезни почек определить невозможно. Статистическая зависимость спектральных характеристик сыворотки крови от выживаемости установлена для 26 пациентов на гемодиализе с использованием мультивариативного анализа. Для построения прогностической модели применён дискриминантный анализ методом наименьших квадратов — метод машинного обучения, позволяющий создавать классификации.</p> <p><bold>Результаты.</bold> Анализ данных проводили в группе пациентов, получающих программный гемодиализ: 13 пациентов, умерших в течение 3 лет после анализа крови, и пять групп по 13 пациентов, отобранных случайным образом из 45 оставшихся. Каждую группу формировали независимо. Модель тестировали в пяти итерациях, результаты усредняли. Наиболее значимыми частотами спектра для прогноза были: 731, 839, 1240, 1391 и 1578 см<sup>−1</sup>. Чувствительность модели прогноза составила 83%; специфичность — 79%, точность — 81%, площадь под кривой ROC (AUC) — 0,86. Во 2-й части исследования установлено, что только две из пяти частот, значимых для прогноза выживаемости, совпадают с частотами, характерными для креатинина и мочевины (637, 724, 1001, 1095, 1238, 1393 см<sup>−1</sup>), которые позволяют различать пациентов с хронической болезнью почек стадий I–IIIа от терминальной стадией с чувствительностью 71%, специфичностью 95% и точностью 83%.</p> <p><bold>Заключение.</bold> Поверхностно-усиленная рамановская спектроскопия сыворотки крови в сочетании с математическим моделированием обладает высокой точностью при минимальных трудозатратах.</p></trans-abstract><trans-abstract xml:lang="zh"><p><bold>研究背景：</bold>预测慢性肾病的结果是现代医学的一项紧迫任务。这项任务可以使用基于生物标志物的分层系统来解决，生物标志物包括代谢，电解质，炎症和仪器指标。</p> <p><bold>目的：</bold>为了确定血清表面增强拉曼光谱在评估接受程序性血液透析的终末期慢性肾病患者的总体死亡率方面的预后意义。</p> <p><bold>研究对象与方法：</bold>前瞻性随访包括58名33-73岁（平均年龄-57.0±12.9岁）的男女患者进行程序性血液透析。在3年的随访中，登记了13例死亡。为了鉴定与死亡率相关的表型鉴定相关的光谱特征，另外形成了75名患者的比较组（平均年龄—51.33±13.12年，<italic>p</italic> &lt;0.01），其估计的肾小球滤过率对应于慢性肾病 根据现代标准，慢性肾病的诊断是在存在肾功能障碍迹象的情况下建立的，包括持续3个月或更长时间的一种或另一种估计的肾小球滤过率。然而，不可能确定慢性肾脏疾病无症状阶段的确切持续时间。使用多变量分析建立了26例血液透析患者血清光谱特征对生存期的统计学依赖性。为了构建预测模型，使用最小二乘法进行判别分析，这是一种允许您创建分类的机器学习方法。</p> <p><bold>结果：</bold>在一组接受程序性血液透析的患者中进行数据分析：在血液检查后3年内死亡的13名患者，以及从剩余的45名中随机选择的5组13名患者。各组独立形成。该模型在五次迭代中进行测试，并对结果进行平均。预测频谱的最显着频率为：731，839，1240，1391和1578cm<sup>−1</sup>。预测模型的灵敏度为83％;特异性为79％，准确度为81％，ROC曲线下面积（AUC）为0.86。在研究的第二部分中，发现对于生存预后显着的五个频率中只有两个与肌酐和尿素的频率特征一致(637, 724, 1001, 1095, 1238, 1393cm<sup>−1</sup>)，这使得能够以71%的敏感性、95%的特异性和83%的准确度将患有慢性肾病阶段I–IIIa的患者与终端a阶段区分开来。</p> <p><bold>结论：</bold>血清表面增强拉曼光谱与数学建模相结合，具有很高的精度和最小的努力。</p></trans-abstract><kwd-group xml:lang="en"><kwd>surface-enhanced Raman spectroscopy</kwd><kwd>chronic kidney disease</kwd><kwd>maintenance hemodialysis</kwd><kwd>prognosis</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>поверхностно-усиленная рамановская спектроскопия</kwd><kwd>хроническая болезнь почек</kwd><kwd>программный гемодиализ</kwd><kwd>прогноз</kwd></kwd-group><kwd-group xml:lang="zh"><kwd>表面增强拉曼光谱</kwd><kwd>慢性肾脏疾病</kwd><kwd>程序性血液透析</kwd><kwd>预后</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Foreman KJ, Marquez N, Dolgert A, et al. 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