Objective:To investigate the correlation between vitamin D levels and thyroid hormone sensitivity in euthyroid individuals.Methods:This cross-sectional study included 5 894 euthyroid individuals who underwent health examinations at the Department of Health Management, Peking Union Medical College Hospital, from December 2023 to February 2024. Thyroid feedback quantile-based index (TFQI), TSH index (TSHI), thyrotroph thyroxine resistance index (TT4RI), and the ratio of free triiodothyronine (FT3)/free thyroxine (FT4) were calculated to assess thyroid hormone sensitivity. Participants were categorized into vitamin D deficiency and non-deficiency groups based on serum 25(OH)D levels. The differences in thyroid hormone sensitivity indices and other clinical characteristics between the two groups were compared. Multivariate logistic regression models were used to analyze the association between vitamin D levels and thyroid hormone sensitivity, and stratified analysis was conducted to explore the association in different genders.Results:Among the study participants, 4 731 (80.3%) had vitamin D deficiency. Compared with the non-deficient group, the deficient group had a lower TFQI (-0.03(-0.31, 0.23) and -0.01(-0.28, 0.27)) ( Z=-2.130, P=0.033) and a higher FT3/FT4 ratio ((0.36±0.04) and (0.35±0.04)) ( t=-4.592, P<0.001). After adjusting for confounding factors including gender and age, the risk of impaired central and peripheral thyroid hormone sensitivity significantly increased in the non-deficient group (TFQI ( OR=1.16, 95% CI: 1.01-1.34); FT3/FT4 ( OR=1.23, 95% CI: 1.05-1.45)) (all, P<0.05). Conclusion:In euthyroid individuals, people with higher vitamin D levels have a higher risk of impaired thyroid hormone sensitivity.

Objective To evaluate the application of flipped classroom(FC)approach in endocrine system integrated course for students from 4+4 clinical medicine pilot class at Peking Union Medical College(PUMC).Methods The study included the students of 4+4 clinical medicine pilot class grades 2019-2023 in PUMC.The students of grades 2019-2021(n=77)served as the control receiving traditional teaching method,while the students of grades 2022 and 2023(n=76)were selected as the experimental group,which were taught by FC approach.The selected teaching content is thyroid theme.The scoring rates of thyroid related questions in the final exam were as-sessed and a questionnaire survey was conducted to evaluate teaching satisfaction and effectiveness.Results The scoring rates of experimental group were significantly higher as compared to that of control group(P＜0.05).Over 90％of the students in the experimental group strongly satisfied or satisfied with the teaching content arrangement,design form,classroom atmosphere,teacher-student interaction of FC and expressed willingness to continue with this methodology.In addition,over 90％of the students strongly agreed or agreed that FC stimulated learning inter-est,improved self-learning ability,strengthened the connection between theory and clinical practice,inspired clini-cal reasoning,enhanced the abilities to analyze and solve problems,and cultivated communication and teamwork skills.Conclusions The application of FC approach in endocrine system integrated course achieved excellent teaching outcomes with high satisfaction of the students.

The Unison(1924)was a yearbook assembled and published by the students of the Peking Union Medical College(PUMC),in honor of the first graduation of PUMC.It comprehensively introduced the organizational history,board of trustees and administration,departments and faculty,medical and nursing clas-ses,student organizations and activities in PUMC.It also published school calendar and songs,alumni record,poems,drama scripts written by PUMC students.It is a comprehensive and systematic record of PUMC and Pe-king Union Medical College Hospital(PUMCH)in 1924,providing rich and valuable details in regards to aca-demic and spiritual lives of faculty and students.Compiled during the early years of PUMC and PUMCH,the book also contributes to the formation of PUMC and PUMCH culture.It advocates for a spirit of science and hu-manity that has significantly influenced the cultivation and development of medical humanistic spirit in China.

Liu Shih-Hao,the founder of endocrinology in China,conducted research on the hypothalam-ic-pituitary-gonadal axis using rats as experimental subjects during his academic training in the United Kingdom in the late 1930s.This aspect of his work has not yet received due attention in prior scholarship.Accordingly,this article provides an overview of this series of studies and situates these relatively micro-level events in medi-cal history within the broader context of Liu Shih-Hao's personal academic trajectory and the historical develop-ment of endocrinology at the time.Furthermore,by connecting these early investigations with Liu's later report,The Direction of Endocrinology Research Development,delivered more than two decades afterward,this paper explores the underlying linkages between them.Through this analysis,the study aims to elucidate the rich historiographical significance of these investigations,thereby contributing to a more comprehensive under-standing of Liu Shih-Hao's academic legacy as well as the establishment and evolution of endocrinology in China.

Objective:To explore the research characteristics of clinical nutrition in China across different periods by systematically analyzing the articles published in the Chinese Journal of Clinical Nutrition over three decades (1993–2024). Methods:We utilized the bibliometric tool VOSviewer to divide the articles published in the Chinese Journal of Clinical Nutrition from 1993 to 2024 into three stages: 1993–2001, 2002–2008, and 2009–2024, for which every two consecutive editorial boards were regarded as one stage. Keyword co-occurrence analysis was conducted and the authors were analyzed. Accordingly, knowledge graphs were drawn to reflect the research characteristics of clinical nutrition in China at various developmental stages. Results:Research on clinical nutrition research in China differed across different stages. From 1993 to 2001, research primarily focused on parenteral and enteral nutrition and nutritional support, exploring their applications for specific diseases. From 2002 to 2008, the content of research became more detailed, and evidence-based methodologies were widely adopted, promoting the transition of research from simple nutrition support to the analysis of nutrition intervention mechanisms and evidence-based practice. From 2009 to 2024, articles published in the Chinese Journal of Clinical Nutrition not only focused on traditional nutritional support and disease interventions but also introduced emerging standards and new diseases, involving more diseases and populations; additionally, the research hotspots extended to interdisciplinary fields, along with continuously evolved research methods and technologies. Conclusions:The evolution of articles published in the Chinese Journal of Clinical Nutrition over the past 32 years not only documented the developmental trajectory of Chinese clinical nutrition from basic technical specifications to precision medicine interventions but also offered a paradigm shift of the discipline from the introduction and digestion of technologies to the independent innovation in formulating clinical nutrition-related guidelines and expert consensuses.

Objective:To explore the research characteristics of clinical nutrition in China across different periods by systematically analyzing the articles published in the Chinese Journal of Clinical Nutrition over three decades (1993–2024). Methods:We utilized the bibliometric tool VOSviewer to divide the articles published in the Chinese Journal of Clinical Nutrition from 1993 to 2024 into three stages: 1993–2001, 2002–2008, and 2009–2024, for which every two consecutive editorial boards were regarded as one stage. Keyword co-occurrence analysis was conducted and the authors were analyzed. Accordingly, knowledge graphs were drawn to reflect the research characteristics of clinical nutrition in China at various developmental stages. Results:Research on clinical nutrition research in China differed across different stages. From 1993 to 2001, research primarily focused on parenteral and enteral nutrition and nutritional support, exploring their applications for specific diseases. From 2002 to 2008, the content of research became more detailed, and evidence-based methodologies were widely adopted, promoting the transition of research from simple nutrition support to the analysis of nutrition intervention mechanisms and evidence-based practice. From 2009 to 2024, articles published in the Chinese Journal of Clinical Nutrition not only focused on traditional nutritional support and disease interventions but also introduced emerging standards and new diseases, involving more diseases and populations; additionally, the research hotspots extended to interdisciplinary fields, along with continuously evolved research methods and technologies. Conclusions:The evolution of articles published in the Chinese Journal of Clinical Nutrition over the past 32 years not only documented the developmental trajectory of Chinese clinical nutrition from basic technical specifications to precision medicine interventions but also offered a paradigm shift of the discipline from the introduction and digestion of technologies to the independent innovation in formulating clinical nutrition-related guidelines and expert consensuses.

Liu Shih-Hao,the founder of endocrinology in China,conducted research on the hypothalam-ic-pituitary-gonadal axis using rats as experimental subjects during his academic training in the United Kingdom in the late 1930s.This aspect of his work has not yet received due attention in prior scholarship.Accordingly,this article provides an overview of this series of studies and situates these relatively micro-level events in medi-cal history within the broader context of Liu Shih-Hao's personal academic trajectory and the historical develop-ment of endocrinology at the time.Furthermore,by connecting these early investigations with Liu's later report,The Direction of Endocrinology Research Development,delivered more than two decades afterward,this paper explores the underlying linkages between them.Through this analysis,the study aims to elucidate the rich historiographical significance of these investigations,thereby contributing to a more comprehensive under-standing of Liu Shih-Hao's academic legacy as well as the establishment and evolution of endocrinology in China.

Objective:To investigate the correlation between vitamin D levels and thyroid hormone sensitivity in euthyroid individuals.Methods:This cross-sectional study included 5 894 euthyroid individuals who underwent health examinations at the Department of Health Management, Peking Union Medical College Hospital, from December 2023 to February 2024. Thyroid feedback quantile-based index (TFQI), TSH index (TSHI), thyrotroph thyroxine resistance index (TT4RI), and the ratio of free triiodothyronine (FT3)/free thyroxine (FT4) were calculated to assess thyroid hormone sensitivity. Participants were categorized into vitamin D deficiency and non-deficiency groups based on serum 25(OH)D levels. The differences in thyroid hormone sensitivity indices and other clinical characteristics between the two groups were compared. Multivariate logistic regression models were used to analyze the association between vitamin D levels and thyroid hormone sensitivity, and stratified analysis was conducted to explore the association in different genders.Results:Among the study participants, 4 731 (80.3%) had vitamin D deficiency. Compared with the non-deficient group, the deficient group had a lower TFQI (-0.03(-0.31, 0.23) and -0.01(-0.28, 0.27)) ( Z=-2.130, P=0.033) and a higher FT3/FT4 ratio ((0.36±0.04) and (0.35±0.04)) ( t=-4.592, P<0.001). After adjusting for confounding factors including gender and age, the risk of impaired central and peripheral thyroid hormone sensitivity significantly increased in the non-deficient group (TFQI ( OR=1.16, 95% CI: 1.01-1.34); FT3/FT4 ( OR=1.23, 95% CI: 1.05-1.45)) (all, P<0.05). Conclusion:In euthyroid individuals, people with higher vitamin D levels have a higher risk of impaired thyroid hormone sensitivity.

A 28-year-old woman presented with a 4-year history of fatigue and sleepiness and was found to have central hypothyroidism and mood disorder. The patient had normal thyroid volume and did not show any other pituitary axis involvement. Over the course of the disease, her symptom improvement matched with the free thyroxine (FT 4) rebound and the adjustment of antipsychotic medication. The patient′s grandmother had central hypothyroidism, and her mother and uncle had lowered or inappropriately normal thyroid stimulating hormone. Hence, genetic involvement was highly suspected, but whole exon sequencing did not reveal a pathogenic variant. Levothyroxine tablets were prescribed to maintain a normal median level of FT 4, and mood disorder medications were adjusted by specialists. Isolated central hypothyroidism is extremely rare, and we report this case aiming to raise awareness of this condition.

The Unison(1924) was a yearbook assembled and published by the students of the Peking Union Medical College (PUMC), in honor of the first graduation of PUMC. It comprehensively introduced the organizational history, board of trustees and administration, departments and faculty, medical and nursing classes, student organizations and activities in PUMC. It also published school calendar and songs, alumni record, poems, drama scripts written by PUMC students. It is a comprehensive and systematic record of PUMC and Peking Union Medical College Hospital (PUMCH) in 1924, providing rich and valuable details in regards to academic and spiritual lives of faculty and students. Compiled during the early years of PUMC and PUMCH, the book also contributes to the formation of PUMC and PUMCH culture. It advocates for a spirit of science and humanity that has significantly influenced the cultivation and development of medical humanistic spirit in China.