Isoliquiritigenin (ISL) is a chalcone compound isolated from licorice, known for its anti-diabetic, anti-cancer, and antioxidant properties. Our previous study has demonstrated that ISL effectively lowers blood glucose levels in type 2 diabetes mellitus (T2DM) mice and improves disturbances in glucolipid and energy metabolism induced by T2DM. This study aims to further investigate the effects of ISL on alleviating abnormal endoplasmic reticulum stress (ERS) caused by T2DM and to elucidate its molecular mechanisms. In vivo experiments were conducted using 8-week-old SPF male C57BL/6J mice. The T2DM animal model was established by high-fat and high-sugar diet combined with intraperitoneal injections of streptozotocin (STZ), in compliance with the ethical guidelines set by the Animal Welfare Committee of Beijing University of Chinese Medicine (approval number: BUCM-2022021503-1134). In vitro experiments employed human liver cancer HepG2 cells, which were induced with tunicamycin (TM) to establish the ERS cell model. Transcriptomic sequencing was used to analyze changes in gene expression in the liver samples of T2DM mice following ISL treatment. Real-time quantitative polymerase chain reaction (RT-qPCR) was employed to assess the regulatory effects of ISL on key ERS genes. Enzyme-linked immunosorbent assay (ELISA), Western blot (WB), and immunofluorescence techniques were used to evaluate ISL's effects on ERS-related proteins. Results indicate that ISL significantly downregulates the expression of ERS-related genes, reduces the level of glucose-regulated protein 78 (GRP78), and inhibits the phosphorylation of protein kinase RNA-like endoplasmic reticulum kinase (PERK), thereby alleviating abnormal ERS induced by T2DM. Additionally, ISL increases the protein levels of insulin receptor substrate (IRS) 1 and IRS2 and enhances the phosphorylation of protein kinase B (Akt), thereby improving insulin sensitivity. In conclusion, ISL is able to alleviate T2DM associated symptoms by improving abnormal ERS and enhancing insulin sensitivity.

OBJECTIVE: To explore clinical efficacy of percutaneous endoscopic discectomy with a lateral approach and dual-channel method in treating highly free lumbar disc herniation(LDH). METHODS: A retrospective analysis was conducted on 54 patients with highly free LDH who were treated with spinal endoscopic techniques from January 2021 to December 2022. Twenty-seven patients were treated with lateral approach dual-channel(lateral approach dual-channel group), including 16 males and 11 females, with an average age of (54.6±10.5) years old. Twenty-seven patients were treated with unilateral biportal endoscopic (UBE group), including 17 males and 10 females, with an average age of (52.9±12.3) years old. The number of intraoperative fluoroscopy, operation time and hospital stay, as well as visual analogue scale (VAS) and Oswestry diability index (ODI) of low back and leg pain between two patients before operation, 1 day, 1, 3, and 12 months after operation, and the efficacy was evaluated by the modified MacNab criteria at 12 mohths after operation. RESULTS: All patients were successfully completed surgical and were followed up, the time raged from 12 to 22 months with an average of (13.57±4.12) months. There was no statistically significant difference in operation time between two groups (P>0.05). The hospital stay of lateral approach dual-channel group was (3.9±1.1) days, which was shorter than that of UBE group (6.5±1.4) days, the number of intraoperative fluoroscopy in lateral approach dual-channel group was (12.7±2.1) times, which was more than that in UBE group (6.6±1.3) times, the differences were statistically significant (t=5.197, -7.532;P<0.05). VAS and ODI for low back pain at 1 day and 1 month after operation, and VAS for leg pain at 1 day after operation of lateral approach dual-channel group were superior to those of UBE group, and the differences were statistically significant (P<0.05). However, there were no statistically significant differences in VAS and ODI for low back and leg pain between two groups before operation and 3 and 12 months after operation (P>0.05). VAS and ODI of low back and leg pain were significantly improved at each time point before and after operation in both groups, and the difference were statistically significant (P<0.05). At 12 months after operation, according to the modified MacNab criteria, the excellent and good rates of therapeutic effects between lateral approach dual-channel group and UBE group were 92.6% (25/27) and 88.9% (24/27), respectively, and the difference was not statistically significant (χ²=0.22, P>0.05). CONCLUSION For patients with highly free lumbar intervertebral disc protrusion, both of lateral approach dual-channel method and UBE endoscopic surgery are safe and effective. Endoscopic surgery with lateral approach and dual-channel method could be performed under local anesthesia, allowing for the removal of the nucleus pulposus under direct vision. It is simpler, more efficient.
Humans ; Male ; Female ; Intervertebral Disc Displacement/surgery* ; Middle Aged ; Diskectomy, Percutaneous/methods* ; Lumbar Vertebrae/surgery* ; Endoscopy/methods* ; Adult ; Retrospective Studies ; Aged

PURPOSE: To investigate the protective effect of sub-hypothermic mechanical perfusion combined with membrane lung oxygenation on ischemic hypoxic injury of yorkshire brain tissue caused by traumatic blood loss. METHODS: This article performed a random controlled trial. Brain tissue of 7 yorkshire was selected and divided into the sub-low temperature anterograde machine perfusion group (n = 4) and the blank control group (n = 3) using the random number table method. A yorkshire model of brain tissue injury induced by traumatic blood loss was established. Firstly, the perfusion temperature and blood oxygen saturation were monitored in real-time during the perfusion process. The number of red blood cells, hemoglobin content, NA⁺, K⁺, and Ca²⁺ ions concentrations and pH of the perfusate were detected. Following perfusion, we specifically examined the parietal lobe to assess its water content. The prefrontal cortex and hippocampus were then dissected for histological evaluation, allowing us to investigate potential regional differences in tissue injury. The blank control group was sampled directly before perfusion. All statistical analyses and graphs were performed using GraphPad Prism 8.0 Student t-test. All tests were two-sided, and p value of less than 0.05 was considered to indicate statistical significance. RESULTS: The contents of red blood cells and hemoglobin during perfusion were maintained at normal levels but more red blood cells were destroyed 3 h after the perfusion. The blood oxygen saturation of the perfusion group was maintained at 95% - 98%. NA⁺ and K⁺ concentrations were normal most of the time during perfusion but increased significantly at about 4 h. The Ca²⁺ concentration remained within the normal range at each period. Glucose levels were slightly higher than the baseline level. The pH of the perfusion solution was slightly lower at the beginning of perfusion, and then gradually increased to the normal level. The water content of brain tissue in the sub-low and docile perfusion group was 78.95% ± 0.39%, which was significantly higher than that in the control group (75.27% ± 0.55%, t = 10.49, p < 0.001), and the difference was statistically significant. Compared with the blank control group, the structure and morphology of pyramidal neurons in the prefrontal cortex and CA1 region of the hippocampal gyrus were similar, and their integrity was better. The structural integrity of granulosa neurons was destroyed and cell edema increased in the perfusion group compared with the blank control group. Immunofluorescence staining for glail fibrillary acidic protein and Iba1, markers of glial cells, revealed well-preserved cell structures in the perfusion group. While there were indications of abnormal cellular activity, the analysis showed no significant difference in axon thickness or integrity compared to the 1-h blank control group. CONCLUSIONS Mild hypothermic machine perfusion can improve ischemia and hypoxia injury of yorkshire brain tissue caused by traumatic blood loss and delay the necrosis and apoptosis of yorkshire brain tissue by continuous oxygen supply, maintaining ion homeostasis and reducing tissue metabolism level.
Animals ; Perfusion/methods* ; Disease Models, Animal ; Brain Injuries/etiology* ; Swine ; Male ; Hypothermia, Induced/methods*

PURPOSE: Bone cement-reinforced fenestrated pedicle screws (FPSs) have been widely used in the internal fixation and repair of the spine with osteoporosis in recent years and show significant improvement in fixation strength and stability. However, compared with conventional reinforcement methods, the advantages of bone cement-reinforced FPSs remain undetermined. This article compares the effects of fenestrated and conventional pedicle screws (CPSs) combined with bone cement in the treatment of osteoporosis. METHODS: A clinical control study of FPSs and CPSs combined with bone cement reinforcement in osteoporotic vertebral internal fixation was performed using the database PubMed, Embase, Cochrane Library, CNKI, the Wanfang, and the China Biomedical Literature Service System. Two evaluators screened the relevant literature in strict accordance with the inclusion criteria (diagnosis of participants, type of clinical study, treatment with FPS and CPS, and outcome indicators) and exclusion criteria (duplicate literature and missing or incorrect data) and independently conducted data extraction and quality evaluation. Clinical control studies of direct comparison between FPS and CPS combined with bone cement reinforcement in patients who were definitively diagnosed with thoracolumbar fractures or spinal degenerative diseases were included. Quality evaluation was conducted using the Cochrane risk bias evaluation tool for randomized controlled studies and using the Newcastle-Ottawa scale for retrospective case-control studies. RevMan software (version 5.3) was used for the meta-analysis to compare the clinical efficacy, radiological results, and related complications of the 2 methods. RESULTS: A total of 13 articles were included, including 7 randomized controlled studies and 6 retrospective case-control studies. There were 909 patients in these studies, 451 in the FPS and polymethyl methacrylate (FPS & PMMA) group and 458 in the CPS and polymethyl methacrylate (CPS & PMMA) group. The results of the meta-analysis showed that there was no significant difference between the 2 groups in operation time, hospital stay, visual analogue score, Japanese orthopaedic association score, Oswestry disability index score, Cobb angle, vertebral body deformation index and fusion rate (p > 0.05). The mean difference of intraoperative bleeding volume was -10.45, (95% confidence intervals (CI) (-16.92, -3.98), p = 0.002), the mean difference of loss height of the anterior edge of the vertebral body after surgery was -0.69 (95% CI (-0.93, -0.44), p < 0.001), and the relative risk (RR) of overall complication rate was 0.43 (95% CI (0.27, 0.68), p < 0.001), including the RR of bone cement leakage rate was 0.57 (95% CI (0.39, 0.85), p = 0.005). The screw loosening rate (RR = 0.26, 95% CI (0.13, 0.54), p < 0.001) of the FPS group was significantly lower than that of the CPS group. CONCLUSION The existing clinical evidence shows that compared with the CPS combined with bone cement, the use of FPS repair in the internal fixation of an osteoporotic vertebral body can reduce the amount of intraoperative bleeding, be more conducive to maintaining the height of the vertebral body, and significantly reduce the incidence of postoperative complications such as bone cement leakage and screw loosening.
Humans ; Pedicle Screws ; Bone Cements ; Spinal Fractures/surgery* ; Osteoporotic Fractures/surgery* ; Fracture Fixation, Internal/instrumentation*

PURPOSE: The rate of complications among patients undergoing surgery has increased due to infection with SARS-CoV-2 and other variants of concern. However, Omicron has shown decreased pathogenicity, raising questions about the risk of postoperative complications among patients who are infected with this variant. This study aimed to investigate complications and related factors among patients with recent Omicron infection prior to undergoing orthopedic surgery. METHODS: A historical control study was conducted. Data were collected from all patients who underwent surgery during 2 distinct periods: (1) between Dec 12, 2022 and Jan 31, 2023 (COVID-19 positive group), (2) between Dec 12, 2021 and Jan 31, 2022 (COVID-19 negative control group). The patients were at least 18 years old. Patients who received conservative treatment after admission or had high-risk diseases or special circumstances (use of anticoagulants before surgery) were excluded from the study. The study outcomes were the total complication rate and related factors. Binary logistic regression analysis was used to identify related factors, and odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the impact of COVID-19 infection on complications. RESULTS: In the analysis, a total of 847 patients who underwent surgery were included, with 275 of these patients testing positive for COVID-19 and 572 testing negative. The COVID-19-positive group had a significantly higher rate of total complications (11.27%) than the control group (4.90%, p < 0.001). After adjusting for relevant factors, the OR was 3.08 (95% CI: 1.45-6.53). Patients who were diagnosed with COVID-19 at 3-4 weeks (OR = 0.20 (95% CI: 0.06-0.59), p = 0.005), 5-6 weeks (OR = 0.16 (95% CI: 0.04-0.59), p = 0.010), or ≥7 weeks (OR = 0.26 (95% CI: 0.06-1.02), p = 0.069) prior to surgery had a lower risk of complications than those who were diagnosed at 0-2 weeks prior to surgery. Seven factors (age, indications for surgery, time of operation, time of COVID-19 diagnosis prior to surgery, C-reactive protein levels, alanine transaminase levels, and aspartate aminotransferase levels) were found to be associated with complications; thus, these factors were used to create a nomogram. CONCLUSION Omicron continues to be a significant factor in the incidence of postoperative complications among patients undergoing orthopedic surgery. By identifying the factors associated with these complications, we can determine the optimal surgical timing, provide more accurate prognostic information, and offer appropriate consultation for orthopedic surgery patients who have been infected with Omicron.
Humans ; COVID-19/complications* ; Male ; Female ; Middle Aged ; Postoperative Complications/epidemiology* ; SARS-CoV-2 ; Orthopedic Procedures/adverse effects* ; Aged ; Nomograms ; Adult ; Retrospective Studies ; Risk Factors

Isolated male epispadias typically presents with preputial defects and dorsal urethral dehiscence. A less common subtype, known as concealed epispadias, is distinguished by an intact prepuce. Despite its clinical relevance, there is limited literature on this variant. In this study, we retrospectively analyzed the clinical data of 86 pediatric patients with isolated male epispadias treated in Beijing Children's Hospital (Beijing, China) from May 2004 to July 2023, including 19 cases of concealed epispadias and 67 of nonconcealed epispadias. We compared clinical characteristics, preoperative diagnostics, surgical techniques, postoperative outcomes, and sexual function during follow-up between the concealed and nonconcealed groups. No significant differences were observed between the two groups regarding surgical methods, postoperative complications, or rates of urinary incontinence. However, notable distinctions were found in the age at initial diagnosis, timing of surgery, frequency of incontinence, location of the urethral meatus, and postoperative urinary incontinence scores (all P < 0.05). Given the absence of penopubic epispadias in concealed cases, we categorized glans and penile epispadias within nonconcealed epispadias as distal epispadias ( n = 40) and subsequently compared them with concealed epispadias cases. The postoperative urinary incontinence scores did not differ significantly between the concealed and distal epispadias groups. These findings suggest that concealed epispadias represents a relatively milder form of the condition, characterized by the absence of penopubic involvement, lower rates of urinary incontinence, and favorable surgical outcomes. However, the intact prepuce in concealed cases underscores the need for careful identification and early diagnosis.
Humans ; Male ; Retrospective Studies ; Epispadias/classification* ; China ; Tertiary Care Centers ; Child, Preschool ; Child ; Postoperative Complications/epidemiology* ; Urinary Incontinence/epidemiology* ; Urethra/surgery* ; Infant ; Penis/surgery* ; Adolescent ; Urologic Surgical Procedures, Male/methods* ; East Asian People

OBJECTIVE: To investigate the effects and underlying mechanism of ionizing radiation on the adipogenic of mesenchymal stem cells (MSCs). METHODS: Mouse MSCs were cultured in vitro and treated with 2 Gy and 6 Gy radiation with ⁶⁰Co, and the radiation dose rate was 0.98 Gy/min. Bulk RNA-seq was performed on control and irradiated MSCs. The changes of adipogenic differentiation and oxidative stress pathways of MSC were revealed by bioinformatics analysis. Oil Red O staining was used to detect the adipogenic differentiation ability of MSCs in vitro, and real-time fluorescence quantitative PCR (qPCR) was used to detect the expression differences of key regulatory factors Cebpa, Lpl and Pparg after radiation treatment. At the same time, qPCR and Western blot were used to detect the effect of inhibition of Nrf2, a key factor of antioxidant stress pathway, on the expression of key regulatory factors of adipogenesis. Moreover, the species conservation of the irradiation response of human bone marrow MSCs and mouse MSC was determined by qPCR. RESULTS: Bulk RNA-seq suggested that ionizing radiation promotes adipogenic differentiation of MSCs and up-regulation of oxidative stress-related genes and pathways. The results of Oil Red O staining and qPCR showed that ionizing radiation promoted the adipogenesis of MSCs, with high expression of Cebpa, Lpl and Pparg, as well as oxidative stress-related gene Nrf2. Nrf2 pathway inhibitors could further enhance the adipogenesis of MSCs in bone marrow after radiation. Notably, the similar regulation of oxidative pathways and enhanced adipogenesis post irradiation were observed in human bone marrow MSCs. In addition, irradiation exposure led to up-regulated mRNA expression of interleukin-6 and down-regulated mRNA expression of colony stimulating factor 2 in human bone marrow MSCs. CONCLUSION Ionizing radiation promotes adipogenesis of MSCs in mice, and oxidative stress pathway participates in this effect, blocking Nrf2 further promotes the adipogenesis of MSCs. Additionally, irradiation activates oxidative pathways and promotes adipogenic differentiation of human bone marrow MSCs.
Mesenchymal Stem Cells/cytology* ; Oxidative Stress/radiation effects* ; Animals ; Adipogenesis/radiation effects* ; Mice ; Radiation, Ionizing ; Cell Differentiation/radiation effects* ; Humans ; NF-E2-Related Factor 2/metabolism* ; PPAR gamma ; Cells, Cultured

OBJECTIVE: To establish an in vitro cell model simulating acute graft-versus-host disease (aGVHD) bone marrow microenvironment injury with the advantage of mouse serum of aGVHD model and explore the effect of serum of aGVHD mouse on the adipogenic differentiation ability of mesenchymal stem cells (MSCs). METHODS: The 6-8-week-old C57BL/6N female mice and BALB/c female mice were used as the donor and recipient mice of the aGVHD model, respectively. Bone marrow transplantation (BMT) mouse model (n=20) was established by being injected with bone marrow cells (1×10⁷ per mouse) from donor mice within 4-6 hours after receiving a lethal dose (8.0 Gy, 72.76 cGy/min) of γ ray general irradiation. A mouse model of aGVHD (n=20) was established by infusing a total of 0.4 ml of a mixture of donor mouse-derived bone marrow cells (1×10⁷ per mouse) and spleen lymphocytes (2×10⁶ per mouse). The blood was removed from the eyeballs and the mouse serum was aspirated on the 7^th day after modeling. Bone marrow-derived MSCs were isolated from 1-week-old C57BL/6N male mice and incubated with 2%, 5% and 10% BMT mouse serum and aGVHD mouse serum in the medium, respectively. The effect of serum in the two groups on the in vitro adipogenic differentiation ability of mouse MSCs was detected by Oil Red O staining. The expression levels of related proteins PPARγ and CEBPα were detected by Western blot. The expression differences of key adipogenic transcription factors including PPARγ, CEBPα, FABP4 and LPL were determined by real-time quantitative PCR (RT-qPCR). RESULTS: An in vitro cell model simulating the damage of bone marrow microenvironment in mice with aGVHD was successfully established. Oil Red O staining showed that the number of orange-red fatty droplets was significantly reduced and the adipogenic differentiation ability of MSC was impaired at aGVHD serum concentration of 10% compared with BMT serum. Western blot experiments showed that adipogenesis-related proteins PPARγ and CEBPα expressed in MSCs were down-regulated. Further RT-qPCR assay showed that the production of PPARγ, CEBPα, FABP4 and LPL, the key transcription factors for adipogenic differentiation of MSC, were significantly reduced. CONCLUSION The adipogenic differentiation capacity of MSCs is inhibited by aGVHD mouse serum.
Animals ; Mesenchymal Stem Cells/cytology* ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Adipogenesis ; Female ; Cell Differentiation ; Graft vs Host Disease/blood* ; Bone Marrow Cells/cytology* ; PPAR gamma/metabolism* ; Disease Models, Animal ; CCAAT-Enhancer-Binding Protein-alpha/metabolism*

OBJECTIVE: To retrospectively analyze the clinical characteristics, co-mutated genes in newly diagnosed acute myeloid leukemia (AML) patients with NRAS and KRAS gene mutations, and the impact of NRAS and KRAS mutations on prognosis. METHODS: The clinical data and next-generation sequencing results of 80 newly diagnosed AML patients treated at our hospital from December 2018 to December 2023 were collected. The clinical characteristics, co-mutated genes of NRAS and KRAS , and the impact of NRAS and KRAS mutations on prognosis in newly diagnosed AML patients were analyzed. RESULTS: Among 80 newly diagnosed AML patients, NRAS mutations were detected in 20 cases(25.0%), and KRAS mutations were detected in 9 cases(11.3%). NRAS mutations predominantly occurred at codons 12 and 13 of exon 2, as well as codon 61 of exon 3, while KRAS mutations were most commonly occurred at codons 12 and 13 of exon 2, all of which were missense mutations. There were no statistically significant differences observed in terms of age, sex, white blood cell count(WBC), hemoglobin(Hb), platelet count(PLT), bone marrow blasts, first induction chemotherapy regimen, CR1/CRi1 rates, chromosome karyotype, 2022 ELN risk classification and allogeneic hematopoietic stem cell transplantation(allo-HSCT) among the NRAS mutation group, KRAS mutation group and NRAS/KRAS wild-type group (P >0.05). KRAS mutations were significantly correlated with PTPN11 mutations (r =0.344), whereas no genes significantly associated with NRAS mutations were found. Survival analysis showed that compared to the NRAS/KRAS wild-type group, patients with NRAS mutation had a relatively higher 5-year overall survival (OS) rate and relapse-free survival (RFS) rate, though the differences were not statistically significant (P =0.097, P =0.249). Compared to the NRAS/KRAS wild-type group, patients with KRAS mutation had a lower 5-year OS rate and RFS rate, with no significant differences observed (P =0.275, P =0.442). There was no significant difference in the 5-year RFS rate between the KRAS mutation group and NRAS mutation group (P =0.157), but the 5-year OS rate of patients with KRAS mutation was significantly lower than that of patients with NRAS mutation (P =0.037). CONCLUSION In newly diagnosed AML patients, KRAS mutation was significantly correlated with PTPN11 mutation. Compared to patients with NRAS/KRAS wild-type, those with NRAS mutation showed a more favorable prognosis, while patients with KRAS mutation showed a poorer prognosis; however, these differences did not reach statistical significance. Notably, the prognosis of AML patients with KRAS mutation was significantly inferior compared to those with NRAS mutation.
Humans ; Leukemia, Myeloid, Acute/diagnosis* ; Mutation ; Prognosis ; Proto-Oncogene Proteins p21(ras)/genetics* ; GTP Phosphohydrolases/genetics* ; Retrospective Studies ; Membrane Proteins/genetics* ; Female ; Male ; Middle Aged ; Adult ; Aged

OBJECTIVE: To prepare clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSC) with high expression of hematopoietic supporting factors and evaluate their stem cell characteristics. METHODS: Fetal umbilical cord tissues were collected from healthy postpartum women during full-term cesarean section. Wharton's jelly was mechanically separated and hUC-MSCs were obtained by explant culture method and enzyme digestion method in an animal serum-free culture system with addition of human platelet lysate. The phenotypic characteristics of hUC-MSCs obtained by two methods were detected by flow cytometry. The differences in proliferation ability between the two groups of hUC-MSCs were identified through CCK-8 assay and colony forming unit-fibroblast (CFU-F) assay. The differences in multilineage differentiation potential between the two groups of hUC-MSCs were identified through induction of adipogenic, osteogenic, and chondrogenic differentiation. The mRNA expression levels of hematopoietic supporting factors such as SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in the two groups of hUC-MSCs were identified by real-time fluorescence quantiative PCR(RT-qPCR). RESULTS: The results of flow cytometry showed that hUC-MSCs obtained by the two methods both expressed high levels of CD73, CD90 and CD105, while lowly expressed CD31, CD45 and HLA-DR. The results of CCK-8 and CFU-F assay showed that the proliferation ability of hUC-MSCs obtained by explant culture method was better than those obtained by enzyme digestion method. The results of the triple lineage differentiation experiment showed that there was no significant difference in multilineage differentiation potential between the two grous of hUC-MSCs. The results of RT-qPCR showed that the mRNA expression levels of hematopoietic supporting factors SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in hUC-MSCs obtained by explant cultrue method were higher than those obtained by enzyme digestion method. CONCLUSION Clinical-grade hUC-MSCs with high expression levels of hematopoietic supporting factors were successfully cultured in an animal serum-free culture system.
Humans ; Mesenchymal Stem Cells/metabolism* ; Umbilical Cord/cytology* ; Cell Differentiation ; Female ; Cell Proliferation ; Cells, Cultured ; Chemokine CXCL12/metabolism* ; Angiopoietin-1/metabolism* ; Vascular Cell Adhesion Molecule-1/metabolism* ; Stem Cell Factor/metabolism* ; Flow Cytometry ; Pregnancy