It has been demonstrated that long-term space flights have a significantly greater impact on the cardiovascular, skeletal, and nervous systems of astronauts. The structural and functional alterations in the skeletal and muscular systems resulting from exposure to weightlessness can lead to the development of low back pain, significantly impairing the ability of astronauts to perform tasks and respond to emergencies. Both space flight and simulated microgravity have been shown to result in low back pain among astronauts, with the following factors identified as primary contributors to this phenomenon. The occurrence of intervertebral disc (IVD) edema results in the stimulation of type IV mechanoreceptors, which subsequently activate nociceptive afferents. The protrusion of an IVD causes compression of the spinal nerve roots. Furthermore, the elongation of the vertebral column and/or the diminished lumbar curvature of the spine exert traction on the dorsal root nerves. Paravertebral muscle degeneration leads to the inhibition of decreased nociceptive activity of the wide-dynamic range neurons of the spinal dorsal horn. Moreover, endogenous pain descending facilitation triggered by conditioning stimulation can be enhanced via the thalamic mediodorsal nuclei, while endogenous pain descending inhibition triggered by conditioning stimulation can be weakened via the thalamic ventromedial nuclei. Psychological factors may contribute to the development of low back pain. The mechanisms governing the generation, maintenance, and alleviation of low back pain in weightlessness differ from those observed in normal gravitational environments. This presents a significant challenge for space medicine research. Therefore, the elucidation of the occurrence and development mechanism of low back pain in weightlessness is important for the prevention and treatment during space flight. To reduce the incidence of low back pain during long-term missions on the space station, astronauts may choose to wear specialized space clothing that can provide axial physiological loads, designed to stimulate both musculature and skeletal structures, mitigating potential increases in vertebral column length, diminished lumbar curvature, and intervertebral disc edema and/or muscular atrophy. Additionally, assuming a “fetal tuck position” described as the knees to chest position may increase lumbar IVD hydrostatic pressure, subsequently reducing disc volume, rectifying diminished lumbar curvature, and alleviating dorsal root nerve tensions. Moreover, this position may reduce type IV mechanoreceptor facilitation and nerve impulse propagation from the sinuvertebral nerves of the annulus fibrosus. Elongated posterior soft tissues (apophyseal joint capsules and ligaments) with spinal flexion may potentially stimulate type I and II mechanoreceptors. It is also recommended to exercise the paraspinal muscles to prevent and alleviate the decrease in their cross-sectional area and maintain their structure and function. Photobiomodulation has been proved to be an effective means of activating the pain descending inhibition pathway of the central nervous system. In addition, astronauts should be encouraged to participate in mission-related activities and strive to avoid psychological problems caused by the long-term confinement in a small space station. The article presents a concise review of potential causes and targeted treatment strategies for low back pain induced by space flight or simulated microgravity in recent years. Its objective is to further elucidate the mechanisms underlying the occurrence and development of low back pain in weightless environments while providing scientific evidence to inform the development of guidelines for preventing, treating, and rehabilitating low back pain during long-term space flights.

Background: This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults. Methods: Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years. Results: The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lympho­cyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age. Conclusions This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.

Purpose: Cystic duct cancers (CDCs) have been classified as extrahepatic bile duct cancers or gallbladder cancers (GBCs); however, it is unclear whether their clinical behavior is similar to that of distal extrahepatic bile duct cancers (DBDCs) or GBCs. Materials and Methods: T category of the CDCs was classified using current T category scheme of the GBCs and DBDCs, and clinicopathological factors were compared among 38 CDCs, 345 GBCs, and 349 DBDCs. We modified Nakata’s classifications (type 1, confined within cystic duct [CD]; combined types 2-4, extension beyond CD) and compared them. Results: No significant overall survival (OS) difference was observed between the patients with CDC, GBC, and DBDC. The T category of GBC staging was more accurate at distinguishing OS in patients with CDC than the DBDC staging. Patients with T3 CDC and GBC showed a significant OS difference when using the T category for GBC staging, while those with T1-T2 CDC and GBC showed no significant difference. In contrast, the T category of DBDC staging did not show any significant OS difference between patients with T1-T2 CDC and DBDC or T3 CDC and DBDC. Patients with type 1 CDC had significantly better OS than those with combined types. Conclusion Unlike GBCs and DBDCs, CDCs exhibit distinct clinicopathological characteristics. The OS is better when the CDC confines within the CD, compared to when it extends beyond it. Therefore, we propose a new T category scheme (T1, confined to CD; T2, invaded beyond CD) for better classifying CDCs.

Background: s/Aims: Non-invasive models stratifying clinically significant portal hypertension (CSPH) are limited. Herein, we developed a new non-invasive model for predicting CSPH in patients with compensated cirrhosis and investigated whether carvedilol can prevent hepatic decompensation in patients with high-risk CSPH stratified using the new model. Methods: Non-invasive risk factors of CSPH were identified via systematic review and meta-analysis of studies involving patients with hepatic venous pressure gradient (HVPG). A new non-invasive model was validated for various performance aspects in three cohorts, i.e., a multicenter HVPG cohort, a follow-up cohort, and a carvediloltreating cohort. Results: In the meta-analysis with six studies (n=819), liver stiffness measurement and platelet count were identified as independent risk factors for CSPH and were used to develop the new “CSPH risk” model. In the HVPG cohort (n=151), the new model accurately predicted CSPH with cutoff values of 0 and –0.68 for ruling in and out CSPH, respectively. In the follow-up cohort (n=1,102), the cumulative incidences of decompensation events significantly differed using the cutoff values of <–0.68 (low-risk), –0.68 to 0 (medium-risk), and >0 (high-risk). In the carvediloltreated cohort, patients with high-risk CSPH treated with carvedilol (n=81) had lower rates of decompensation events than non-selective beta-blockers untreated patients with high-risk CSPH (n=613 before propensity score matching [PSM], n=162 after PSM). Conclusions Treatment with carvedilol significantly reduces the risk of hepatic decompensation in patients with high-risk CSPH stratified by the new model.

Isosteviol is a tetracyclic diterpenoid compound obtained by hydrolysis of natural stevia glycoside under acidic conditions. It has many pharmacological activities, such as anti-tumor, hypoglycemic, anti-inflammatory and antibacterial. Due to its low water solubility, low activity and low bioavailability, isosteviol has poor performance. In order to overcome these shortcomings, scholars have obtained a large number of isosteviol derivatives with novel structures and excellent activity. In this paper, we review the recent progress in the research on the structure modification, biological activity, structure-activity relationship and microbial transformation of isosteviol, in order to provide a reference for the development of new drugs of isosteviol and its derivatives.

Eight compounds were isolated and purified from the ethyl acetate part of 70% acetone extract of Rehmannia glutinosa by various chromatographic techniques such as silica gel, MCI gel CHP-20, ODS, Toyopearl HW-40C, combined with TLC and semi-preparative HPLC. Their structures were elucidated by modern spectroscopy techniques (NMR, MS, UV, IR), and identified as neomartynoside A (1), osmanthuside B₆ (2), martynoside (3), isomartynoside (4), (E)-p-hydroxycinnamic acid (5), caffeic acid (6), ferulic acid (7), and methyl caffeate (8). Compound 1 is a new phenylethanol glycoside, which was identified as neomartynoside A. Compound 2 was isolated from Rehmannia glutinosa for the first time. In addition, compounds 2, 6 and 7 significantly increased relative glucose consumption, showing potential hypoglycemic activity.

[Objective] To explore the accuracy and feasibility of non-invasive prenatal diagnosis of fetal RhE genotype using cell-free fetal DNA (cff-DNA) from maternal peripheral blood. [Methods] A total of 134 pregnant women with single fetuses and RhE-negative blood group were selected from our hospital from November 2023 to August 2024. Free DNA extraction kit was used to extract free DNA from peripheral blood of pregnant women, and the RhE blood group genotype of free DNA was detected by real-time fluorescent quantitative PCR (RT-qPCR). If the qPCR amplification signal of the sample was negative, the methylated RASSF1A gene was amplified, and the positive amplification result was used as a sign of successful extraction of cff-DNA. Serological microcolumn gel method was used to detect the phenotype of RhE blood group in neonatal peripheral blood. [Results] Among the 134 maternal peripheral blood samples, the cff-DNA detection of RhE blood group phenotypes was consistent with the RhE blood group genotyping of neonatal peripheral blood in 133 cases, including 90 cases of Rhee genotype and 43 cases of RhE genotype, with diagnostic concordance rate of 99.3%, sensitivity of 97.7%, specificity of 100%, youden index of 0.977, area under ROC curve of 0.995, the Kappa value of 0.983, positive predictive value of 100%, and negative predictive value of 98.9%. The sample of 1 case failed to be detected. After the amplification of methylated RASSFIA gene, it was confirmed that the reason for the failure was that no cff-DNA was extracted from the sample. The diagnostic concordance rates of the first, second and third trimesters were 93.8% (15/16), 100% (51/51) and 100% (67/67), respectively. Fisher's exact test method was used to calculate the P value, which was P>0.05, indicating that there was no statistical significance in the difference of diagnostic concordance rate among the three pregnancy periods, and there was no difference in the detection concordance rate of this method in different pregnancy periods. [Conclusion] The use of cff-DNA in maternal peripheral blood for the detection of fetal RhE blood group genotype is an accurate and highly feasible non-invasive prenatal diagnostic method, which is helpful for the clinical diagnosis of fetal and neonatal hemolytic disease caused by anti-E antibody.

OBJECTIVE To evaluate the cost-utility of switching to gemcitabine maintenance therapy for patients with unresectable malignant mesothelioma after first-line chemotherapy from the perspective of China’s healthcare system. METHODS A partitioned survival model was constructed based on data from the NVALT19 trial， with a cycle length of 21 days， a time horizon of 10 years， and a discount rate of 5%. Key model outputs included total costs， quality-adjusted life year （QALY）， incremental costs， and incremental cost-effectiveness ratio （ICER）， etc. Cost-utility analysis was conducted to evaluate the cost- effectiveness of gemcitabine maintenance therapy （gemcitabine group） plan versus best supportive care （supportive care group） plan for the patients with unresectable malignant mesothelioma after first-line chemotherapy. Sensitivity analyses were performed. RESULTS Compared with the supportive care group plan， the gemcitabine group plan had an ICER of 54 860.50 yuan/QALY， which was significantly lower than the willingness-to-pay （WTP） threshold （3 times China’s 2023 per capita gross domestic product， 268 077 yuan/QALY）， indicating that gemcitabine group plan was cost-effective. One-way sensitivity analysis revealed that end-of-life care costs and adverse event management costs in the gemcitabine group had the greatest impact on ICER. Probabilistic sensitivity analysis showed gemcitabine group plan was 100% cost-effective when WTP exceeded 270 000 yuan/QALY. CONCLUSIONS From the perspective of China’s healthcare system， switching to gemcitabine maintenance therapy after first-line chemotherapy is cost-effective for unresectable malignant mesothelioma.

Background: This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults. Methods: Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years. Results: The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lympho­cyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age. Conclusions This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.