Hidden blood loss and the influential factors after minimally invasive treatment of posterior pelvic ring injury with sacroiliac screw.

BACKGROUND: To analyze the perioperative bleeding and hidden blood loss (HBL) of sacroiliac screw minimally invasive treatment of pelvic posterior ring injury and explore the influential factors of HBL after operation for providing reference for clinical treatment. METHOD: A retrospective analysis was conducted on data from 369 patients with posterior pelvic ring injuries treated with sacroiliac screws internal fixation at our hospital from January 2015 to January 2022. The research was registered in the Chinese Clinical Trial Registry in July 2022 (ChiCTR2200061866). The total blood loss (TBL) and HBL of patients were counted, and the factors such as gender, age, and surgical duration were statistically analyzed. The influential factors of HBL were analyzed by multiple linear regression. RESULTS: The TBL was 417.96 ± 98.05 ml, of which the visible blood loss (VBL) was 37.00 ± 9.0 ml and the HBL was 380.96 ± 68.8 ml. The HBL accounted for 91.14 ± 7.36% of the TBL. Gender, surgical duration, fixed position, and fixed depth had significant effects on the HBL (P < 0.05). CONCLUSIONS: The HBL was the main cause of anemia after minimally invasive treatment of posterior pelvic ring injury with a sacroiliac screw. Gender, surgical duration, fixed position, and fixed depth were closely related to the occurrence of HBL. In clinical treatment, we should consider these influential factors and take effective measures to reduce the impact of HBL on patients.

Genome-Wide CRISPR Screen Identifies an NF2-Adherens Junction Mechanistic Dependency for Cardiac Lineage.

BACKGROUND: Cardiomyocyte differentiation involves a stepwise clearance of repressors and fate-restricting regulators through the modulation of BMP (bone morphogenic protein)/Wnt-signaling pathways. However, the mechanisms and how regulatory roadblocks are removed with specific developmental signaling pathways remain unclear. METHODS: We conducted a genome-wide CRISPR screen to uncover essential regulators of cardiomyocyte specification in human embryonic stem cells using a myosin heavy chain 6 (MYH6)-GFP (green fluorescence protein) reporter system. After an independent secondary sgRNA validation of 25 candidates, we identified NF2 (neurofibromin 2), a moesin-ezrin-radixin like (MERLIN) tumor suppressor, as an upstream driver of early cardiomyocyte lineage specification. Independent monoclonal NF2 knockouts were generated using CRISPR-Cas9, and cell states were inferred through bulk RNA sequencing and protein expression analysis across differentiation time points. Terminal lineage differentiation was assessed by using an in vitro 2-dimensional-micropatterned gastruloid model, trilineage differentiation, and cardiomyocyte differentiation. Protein interaction and post-translation modification of NF2 with its interacting partners were assessed using site-directed mutagenesis, coimmunoprecipitation, and proximity ligation assays. RESULTS: Transcriptional regulation and trajectory inference from NF2-null cells reveal the loss of cardiomyocyte identity and the acquisition of nonmesodermal identity. Sustained elevation of early mesoderm lineage repressor SOX2 and upregulation of late anticardiac regulators CDX2 and MSX1 in NF2 knockout cells reflect a necessary role for NF2 in removing regulatory roadblocks. Furthermore, we found that NF2 and AMOT (angiomotin) cooperatively bind to YAP (yes-associated protein) during mesendoderm formation, thereby preventing YAP activation, independent of canonical MST (mammalian sterile 20-like serine-threonine protein kinase)-LATS (large tumor suppressor serine-threonine protein kinase) signaling. Mechanistically, cardiomyocyte lineage identity was rescued by wild-type and NF2 serine-518 phosphomutants, but not NF2 FERM (ezrin-radixin-meosin homology protein) domain blue-box mutants, demonstrating that the critical FERM domain-dependent formation of the AMOT-NF2-YAP scaffold complex at the adherens junction is required for early cardiomyocyte lineage differentiation. CONCLUSIONS: These results provide mechanistic insight into the essential role of NF2 during early epithelial-mesenchymal transition by sequestering the repressive effect of YAP and relieving regulatory roadblocks en route to cardiomyocytes.

[Progress on treatment of acetabular quadrilateral plate injury].

Acetabular quadrilateral plate injury has become a hot spot and focus in the field of orthopaedic trauma and pelvic floor function in recent years. Although there are five fracture types,they are all based on fracture morphology,without considering the pulling force of ligaments,joint capsular and muscles. A perfect classification needs to describe the displacement of bone mass in three-dimensional space to better guide reduction and fixation. The seven incision and exposure methods are still the traditional open-eye surgery,and how to protect the criss-crossing vascular neural network and pelvic organs is still the focus. Quadrilateral defect causes dislocation of artificial hip joint,and quantitative evaluation of quadrilateral defect volume and revision techniques are still a hot topic. In this paper,the viewpoints of three-dimensional network structure of acetabular pelvic vascular anatomy,anatomical surgical target channel and fixation anchor point of acetabular fracture reduction are proposed to design new techniques for accurate and minimally invasive surgical operations,in order to realize the requirements of rapid orthopedic rehabilitation.

Deleterious Mechanical Deformation Selects Mechanoresilient Cancer Cells with Enhanced Proliferation and Chemoresistance.

Cancer cells in secondary tumors are found to form metastases more efficiently as compared to their primary tumor counterparts. This is partially due to the unfavorable microenvironments encountered by metastasizing cancer cells that result in the survival of a more metastatic phenotype from the original population. However, the role of deleterious mechanical stresses in this change of metastatic potential is unclear. Here, by forcing cancer cells to flow through small capillary-sized constrictions, it is demonstrated that mechanical deformation can select a tumor cell subpopulation that exhibits resilience to mechanical squeezing-induced cell death. Transcriptomic profiling reveals up-regulated proliferation and DNA damage response pathways in this subpopulation, which are further translated into a more proliferative and chemotherapy-resistant phenotype. These results highlight a potential link between the microenvironmental physical stresses and the enhanced malignancy of metastasizing cancer cells which may be utilized as a therapeutic strategy in preventing the metastatic spread of cancer cells.

Current status of robot-assisted surgery in the clinical application of trauma orthopedics in China: A systematic review.

Background and Aims: To elaborate on the development and characteristics of trauma orthopedic robots and their real curative effect in a clinical application through the collection and analysis of relevant literature and reported clinical results. Method: We conducted the Embase, ScienceDirect, Pubmed, Medline, Wanfang, CNKI, and VIP search of the literature on robotic-assisted surgery in trauma orthopedics in China. We combined search terms with "robotic surgery/artificial intelligence surgery/navigation surgery," "trauma/trauma orthopedics," and "China/Chinese." The exclusion criteria were: (1) articles in languages other than English or Chinese, (2) articles focused on other topics other than robotic-assisted surgery in trauma orthopedics of China, (3) article types were not clinical studies (reviews, basic research, etc.), and (4) articles were not included in the Chinese core journals or science citation index. Authors, type of surgery, robot type, and clinical research results were recorded and analyzed. Results: There were three categories of surgical robots in the clinical application of trauma orthopedics (TiRobot, electromagnetic navigation surgical robots, and small medical robots developed by Beijing Jishuitan Hospital). In terms of blood loss, the fluoroscopy time, and fluoroscopy frequency, most studies found that the robot group was significantly better than the traditional group. Conclusions: Robot-assisted surgery has obvious advantages in accuracy, stability, and reducing intraoperative radiation exposure, but there is no final conclusion about functional recovery.

Acrylamide-induced damage to postsynaptic plasticity is CYP2E1 dependent in an SH-SY5Y co-culture system.

Acrylamide (ACR), a neurotoxic substance, is characterized by a range of industrial and population exposures. The effects of ACR on synapses have been examined, but the regulation and molecular mechanism of key proteins related to ACR and its metabolite glycidamide (GA) have not been elucidated. In this study, we constructed two co-culture systems to mimic neurons that do not express and overexpress CYP2E1. In these co-cultures, we observed the effects and relative influence of ACR and GA on cell survival as well as synaptic structural and functional plasticity. Next, we investigated the relationship between ACR-induced nerve damage and key proteins in the postsynaptic membrane. After ACR exposure, cell death and synaptic damage were significantly worse in CYP2E1-overexpressing co-culture systems, suggesting that ACR-induced neurotoxicity may be related to metabolic efficiency (including CYP2E1 activity). Moreover, with increasing doses of ACR, the key postsynaptic membrane proteins PSD-95 expression was reduced and CaMKII and NMDAR-2B phosphorylation was increased. ACR exposure also triggered a rapid dose- and time-dependent increase in intracellular Ca2+, whose changes can affect the expression of the above-mentioned key proteins. In summary, we clarified the relationship between ACR exposure, neuronal damage and postsynaptic plasticity and proposed an ACR-CYP2E1-GA: Ca2+-PSD-95-NMDAR-Ca2+-CaMKII effect chain. This information will further improve the development of an alternative pathway strategy for investigating the risk posed by ACR.

Lung Cancer Induces NK Cell Contractility and Cytotoxicity Through Transcription Factor Nuclear Localization.

Actomyosin-mediated cellular contractility is highly conserved for mechanotransduction and signalling. While this phenomenon has been observed in adherent cell models, whether/how contractile forces regulate the function of suspension cells like natural killer (NK) cells during cancer surveillance, is unknown. Here, we demonstrated in coculture settings that the evolutionarily conserved NK cell transcription factor, Eomes, undergoes nuclear shuttling during lung cancer cell surveillance. Biophysical and biochemical analyses revealed mechanistic enhancement of NK cell actomyosin-mediated contractility, which is associated with nuclear flattening, thus enabling nuclear entry of Eomes associated with enhanced NK cytotoxicity. We found that NK cells responded to the presumed immunosuppressive TGFß in the NK-lung cancer coculture medium to sustain its intracellular contractility through myosin light chain phosphorylation, thereby promoting Eomes nuclear localization. Therefore, our results demonstrate that lung cancer cells provoke NK cell contractility as an early phase activation mechanism and that Eomes is a plausible mechano-responsive protein for increased NK cytotoxicity. There is scope for strategic application of actomyosin-mediated contractility modulating drugs ex vivo, to reinvigorate NK cells prior to adoptive cancer immunotherapy in vivo (177 words).

Biomarkers of exposure and effect in the serum and urine of rats or workers exposed to 1-bromopropane.

Extensively used in several industries in China as a cleaning agent, 1-bromopropane (1-BP) has significant adverse effects on the central nervous system. However, neither its mechanism of action nor sensitive biomarkers related to it have been determined thus far. In this study, animal experiments and occupational surveys were performed to explore the typical exposure and effect biomarkers of neurotoxicity induced by 1-BP. Male Wistar rats were exposed to 0, 500, or 1000 ppm of 1-BP followed by pathological and biomarker analyses. An epidemiological survey was conducted on 71 workers each from 1-BP exposed and control groups. Serum and urine samples were collected for biomarker testing. cNSE represents neuron-specific enolase (NSE) in the cerebral cortex, where as sNSE represents NSE in the serum; similar terminology applies to S-100ß, and cyclooxygenase-2 (COX-2). In rats exposed to 1000 ppm 1-BP, pathological changes were observed in Purkinje cells, lumbar gray matter, and tibiofibular nerve, while levels of cNSE, cS-100ß, cCOX-2, sS-100ß, and sCOX-2 were significantly elevated at different time checkpoints. In the 500 ppm group, cCOX-2, sNSE, and sCOX-2 levels were significantly elevated at different time checkpoints. 1-BP and N-acetyl-S-(n-propyl)-L-cysteine (AcPrCys) were detected in rat urine, and there was a correlation between the level of sNSE or sCOX-2 and AcPrCys in the 500 ppm group. In the occupational epidemiological study, a significant correlation between AcPrCys and exposure concentration was also detected. The findings of this study indicated that AcPrCys was a sensitive exposure biomarker of 1-BP in rats as well as occupational populations.

Brain-derived neurotrophic factor protects against acrylamide-induced neuronal and synaptic injury via the TrkB-MAPK-Erk1/2 pathway.

Acrylamide has been shown to be neurotoxic. Brain-derived neurotrophic factor (BDNF) can alleviate acrylamide-induced synaptic injury; however, the underlying mechanism remains unclear. In this study, dibutyryl-cyclic adenosine monophosphate-induced mature human neuroblastoma (NB-1) cells were exposed with 0-100 µg/mL acrylamide for 24-72 hours. Acrylamide decreased cell viability and destroyed synapses. Exposure of co-cultured NB-1 cells and Schwann cells to 0-100 µg/mL acrylamide for 48 hours resulted in upregulated expression of synapsin I and BDNF, suggesting that Schwann cells can activate self-protection of neurons. Under co-culture conditions, activation of the downstream TrkB-MAPK-Erk1/2 pathway strengthened the protective effect. Exogenous BDNF can increase expression of TrkB, Erk1/2, and synapsin I, while exogenous BDNF or the TrkB inhibitor K252a could inhibit these changes. Taken together, Schwann cells may act through the BDNF-TrkB-MAPK-Erk1/2 signaling pathway, indicating that BDNF plays an important role in this process. Therefore, exogenous BDNF may be an effective treatment strategy for acrylamide-induced nerve injury. This study was approved by the Laboratory Animal Welfare and Ethics Committee of the National Institute of Occupational Health and Poison Control, a division of the Chinese Center for Disease Control and Prevention (approval No. EAWE-2017-008) on May 29, 2017.

BNIP-2 retards breast cancer cell migration by coupling microtubule-mediated GEF-H1 and RhoA activation.

Microtubules display dynamic turnover during cell migration, leading to cell contractility and focal adhesion maturation regulated by Rho guanosine triphosphatase activity. This interplay between microtubules and actomyosin is mediated by guanine nucleotide exchange factor (GEF)-H1 released after microtubule depolymerization or microtubule disconnection from focal adhesions. However, how GEF-H1 activates Rho upon microtubule disassembly remains elusive. Here, we found that BNIP-2, a BCH domain-containing protein that binds both RhoA and GEF-H1 and traffics with kinesin-1 on microtubules, is important for GEF-H1-driven RhoA activation upon microtubule disassembly. Depletion of BNIP-2 in MDA-MB-231 breast cancer cells decreases RhoA activity and promotes cell migration. Upon nocodazole-induced microtubule disassembly, the interaction between BNIP-2 and GEF-H1 increases, while knockdown of BNIP-2 reduces RhoA activation and cell rounding via uncoupling RhoA-GEF-H1 interaction. Together, these findings revealed that BNIP-2 couples microtubules and focal adhesions via scaffolding GEF-H1 and RhoA, fine-tuning RhoA activity and cell migration.

Schwann cells protect against CaMKII- and PKA-dependent Acrylamide-induced Synapsin I phosphorylation.

OBJECTIVES: To explore the effects of Acrylamide (ACR), as well as the influence of Schwann cells (SCs), on the signal transduction pathway and phosphorylation of Synapsin I in a Human neuroblastoma cell line (NB-1). METHODS: NB-1s, NB-1s co-cultured with SCs, and a negative control group (NB-1 cells without ACR) were exposed to gradient concentrations of ACR for 48 h. Cell proliferation and viability were determined by MTT. Protein and mRNA expression levels of typical kinases (i.e., cAMP-dependent protein kinase [PKA], calcium/calmodulin-dependent protein kinase II [CaMKII], and mitogen-activated protein kinase-extracellular signal-regulated kinases [MAPK-Erk]), their phosphorylation status, as well as Synapsin I and its phosphorylation status, were tested by western blotting and polymerase chain reaction, respectively. Further, the effect of SCs on ACR-induced NB-1 cell toxicity was evaluated. RESULTS: (1) The MTT assay showed a sustained, dose- and time-dependent inhibition of NB-1s exposed to ACR. (2) ACR exposure increased the phosphorylation of CaMKII and PKA, which subsequently increased the phosphorylation of Synapsin I (at Serine603 [a substrate site of CaMKII] and Serine9 [a substrate site of PKA]). Pretreatment with CaMKII and PKA inhibitors blocked the ACR-mediated increase in phosphorylation. The above-described results were all significantly different when compared to the control group (p < 0.05). (3) When co-cultured with SCs, ACR-induced NB-1 inhibition was obviously decreased, and the trend of change of phosphorylated CaMKII, PKA, and Synapsin I were changed (first slightly increased and then decreased), which was inconsistent with what we observed in NB-1s cultured alone. CONCLUSIONS: The toxic effects of ACR on neurons may be mediated by CaMKII and PKA-dependent signaling pathways in which Synapsin I may act as a downstream effector. Furthermore, glial cells (SCs) may be able to prevent a certain degree of ACR-induced neuronal damage.

[Tumor markers of workers exposed to vinyl chloride].

OBJECTIVE: To detect the changes of serum tumor markers of vinyl chloride, and find the influencing factors of tumor markers. METHODS: Two hundred and twenty-three workers exposed to vinyl chloride from a chlor alkali plant and one hundred and forty-nine workers without occupational exposure to vinyl chloride were recruited into this study. Detected 11 tumor markers in serum of the objective. RESULTS: The contentsof carcino-embryonic antigen( CEA), alpha-fetoprotein( AFP), CA-199 and CA72-4 in exposed group increased with the length of service, while the content of neuron-specific enolase( NSE) decreased with the length of service, but there was no correlation between contents of tumor markers and the length of service, which had no statistical significance( P > 0. 05). By univariate analysis, the difference between the exposed group and the control group in the level of thiodiglycolic acid had statistical significance( Z =-16. 178, P < 0. 001). By univariate analysis, gender had effect on CEA, AFP and NSE( Z =-4. 815, -2. 052 and-4. 535, P < 0. 05), smoking had effect on CA-199( Z =-2. 016, P < 0. 05), vinyl chloride exposure had effect on AFP and NSE( Z =-3. 763 and-2. 140, P < 0. 05). By multivariate analysis, CEA and NSE of women were lower than those of men( t =-3. 696 and-5. 722, P < 0. 05). That vinyl chloride exposure was a factor in NSE and NSE of the exposed group were higher than the control group( t =2. 061, P < 0. 05). CONCLUSION: Under the current exposure concentration, exposure to vinyl chloride can change the contents of tumor markers. As the time of exposure to harmful factors increases, the level of tumor markers changes, and the possibility of tumor increases. The level of thiodiglycolic acid may be related to some tumor markers. The influencing factors of different tumor markers are different.

Activation of the Constitutive Androstane Receptor Increases the Therapeutic Index of CHOP in Lymphoma Treatment.

The constitutive androstane receptor (CAR and NR1i3) is a key regulator of CYP2B6, the enzyme predominantly responsible for the biotransformation of cyclophosphamide (CPA) to its pharmacologically active metabolite, 4-hydroxycyclophosphamide (4-OH-CPA). Previous studies from our laboratory illustrated that CAR activation increases the formation of 4-OH-CPA; however, CPA is rarely used clinically outside of combination therapies. Here, we hypothesize that including a selective human CAR activator with the CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen can improve the efficacy without exacerbating off-target toxicity of this regimen in non-Hodgkin lymphoma treatment. In this study, we have developed a novel multiorgan coculture system containing human primary hepatocytes for hepatic metabolism, lymphoma cells as a model target for CHOP, and cardiomyocytes as a major site of off-target toxicity associated with this regimen. We found that a selective human CAR activator, CITCO (6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde-O-(3,4-dichlorobenzyl)oxime), altered expression of key drug-metabolizing enzymes and transporters in human hepatocytes, which positively affects the metabolic profile of CHOP. Coadministration of CITCO and CHOP in the coculture model led to significantly enhanced cytotoxicity in lymphoma cells but not in cardiomyocytes. Moreover, the beneficial effects of CITCO were abrogated when CAR knockout HepaRG cells were used in the coculture model. Importantly, synergistic anticancer effects were observed between CITCO and CHOP, in that inclusion of CITCO alongside the CHOP regimen offers comparable antineoplastic activity toward lymphoma cells at significantly reduced drug concentrations, and the decreased CHOP load attenuates cardiotoxicity. Overall, these findings provide a potentially promising novel strategy for facilitating CHOP-based chemotherapy.

Quantitative high-throughput identification of drugs as modulators of human constitutive androstane receptor.

The constitutive androstane receptor (CAR, NR1I3) plays a key role in governing the transcription of numerous hepatic genes that involve xenobiotic metabolism/clearance, energy homeostasis, and cell proliferation. Thus, identification of novel human CAR (hCAR) modulators may not only enhance early prediction of drug-drug interactions but also offer potentially novel therapeutics for diseases such as metabolic disorders and cancer. In this study, we have generated a double stable cell line expressing both hCAR and a CYP2B6-driven luciferase reporter for quantitative high-throughput screening (qHTS) of hCAR modulators. Approximately 2800 compounds from the NIH Chemical Genomics Center Pharmaceutical Collection were screened employing both the activation and deactivation modes of the qHTS. Activators (115) and deactivators (152) of hCAR were identified from the primary qHTS, among which 10 agonists and 10 antagonists were further validated in the physiologically relevant human primary hepatocytes for compound-mediated hCAR nuclear translocation and target gene expression. Collectively, our results reveal that hCAR modulators can be efficiently identified through this newly established qHTS assay. Profiling drug collections for hCAR activity would facilitate the prediction of metabolism-based drug-drug interactions, and may lead to the identification of potential novel therapeutics.

[Establishment and application of an in vitro model for dynamic direct exposure of lung epithelial cells (A549) to airborne compounds].

OBJECTIVE: To establish and apply a dynamic in vitro model for direct exposure of human cells to gaseous contaminants to investigate the cellular responses to airborne chemical exposures. METHODS: Nitrogen dioxide (NO2) was selected as a model gas compound. Standard test atmospheres were generated (5.1 - 20.7 mg/m3), using clean air dilution method. A549 pulmonary type II-like epithelial cell lines and skin fibroblasts were grown on porous membranes. Human cells on transwell inserts were placed in horizontal diffusion chambers and exposed to various airborne concentrations of NO2 directly at the air- liquid interface for 1 h at 37 degrees C, 15 ml/min. The gasoline exhuast at different load (idle with cold start, 50% and 100% load) collected in Tedlar air bag directly exposed A549 cell for 15 min at 37 degrees C, 10 ml/min. Cytotoxicity of the test gas was investigated using the MTT, NRU (neutral red uptake) and CCK-8 assays. RESULTS: Dose-dependent effects of NO2 were observed in human cells tested which resulted in a significant reduction of cell viability at different concentrations of NO2 (MTT estimated curve:gamma(MTT) = 0.989 - 0.021 chi (NO(2)) R2 = 0.84, P < 0.01; NUR estimated curve:gamma(NUR) = 1.032 - 0.026 chi (NO(2)) R2 = 0.88, P < 0.01). Gasoline exhaust exposure at different load resulted in a decreased cell viability (significantly CCK-8 and MTT levels reduction than air exposure group). CONCLUSION: The dynamic direct exposure method can be used for in vitro inhalational and dermal toxicity studies and potentially as an new technology for biomonitoring of airborne contaminants in future occupational and environmental toxicity assessments.

[Genetic damage in peripheral blood lymphocyte of 1,3-butadiene workers].

OBJECTIVE: To investigate the DNA and chromosome damage in peripheral blood lymphocyte of workers occupationally exposed to 1,3-butadiene (BD). METHODS: Personal information including occupational history, age, sex, smoking and drinking status was collected by the questionnaire. Gas chromatography was used to analyze the BD level. One hundred and eighty 1,3-butadiene workers and 58 controls without occupational BD exposure were investigated. Comet assay and cytokinesis-block micronucleus (CBMN) detection were used to evaluate DNA and chromosomal damage levels in peripheral blood lymphocyte. RESULTS: The concentration of BD in the working environment of BD-exposed workers was 1.80 (0.59-2.76) mg/m3. The rate of CBMN, NPB, NBUD and Olive TM of lymphocyte in BD-exposed workers [(6.76 +/- 4.99) per thousand, 1.00 (0.00-4.00), 2.00 (0.00-7.00) and 4.64 (3.50-5.98), respectively] were higher than those in controls [(3.10 +/- 2.65) per thousdand, 0.00 (0.00-2.80), 1.00 (0.00- 5.00) and 2.34 (0.82-3.93), P < 0.01]. According to the length of work, 180 BD-exposed workers were classified into 3 groups: 1 yrs-, 14.0 yrs- and 20.0 yrs-group, respectively after adjusting the age,sex, smoking and drinking, the rate of CBMN was a rising tendency along with the increase in length of work. CONCLUSION: Under present BD exposure levels, both comet assay and Cytokinesis-block micronucleus test could detect BD-induced genotoxicity in BD-exposed workers, and are more suitable to assess the cumulative damage effect on DNA.

Triptolide induces adverse effect on reproductive parameters of female Sprague-Dawley rats.

The aim of this study was to investigate the adverse effects of triptolide, a diterpenoid triepoxid and a major active component isolated from Triptergium wilfordii Hook.f (TWHF), on various reproductive parameters of female Sprague-Dawley (SD) rats. Female SD rats were treated with triptolide by oral administration (gastric infusion; 0, 100, 200, and 400 µg/kg) once-daily for 90 days. During the experimental period, vaginal smears were taken to monitor the estrous phase for the last 30 days. Relative ovary and uterus weights to body and histopathologically changes were determined on the last day. Serum levels of estradiol (E(2)), progesterone (P), follicle-stimulating hormone (FSH), and luteotropic hormone (LH) were assessed by enzyme immunoassay. ERα expression in the uterus and ovaries were analyzed from using immunohistochemical detection. The results showed that treatment with 200 and 400 ug/kg of triptolide significantly reduced serum levels of E(2) and P and increased levels of FSH and LH. At these dose levels, relative weights of ovary and uterus were significantly reduced. Qualitative histological analysis of the ovaries revealed a reduction in developing follicles and increase in atretic follicles in treated animals. Further, estrous cycles were prolonged significantly. The expression of ERα in ovaries and the uterus decreased in treated animals. These data suggest that triptolide had a direct effect on the ovaries, and the decrease in steroids elicited feedback on FSH and LH. Thus, reduced levels of E(2) and P may affect follicular development, estrous cycle, and expression of ERα.

[Association of XRCC4 polymorphisms and chromosomal damage levels in 1,3-butadiene workers].

OBJECTIVE: To investigate the association of polymorphisms of DNA double-strand break repair gene XRCC4 and chromosomal damage levels in peripheral blood lymphocyte in workers exposed to 1,3-butadien (BD). METHODS: 189 BD exposed workers and 83 controls were recruited in this study. Chromosomal damage in peripheral lymphocytes was measured by the cytokinesis-block micronucleus (CBMN) assay. Three haplotpe-tagging single nucleotide polymorphisms in XRCC4 gene, including A245G, T1394G and C1475T, were detected by PCR-RFLP and the XRCC4 haplotypes were estimated by using an extension of Clark algorithm. The associations between haplotype pairs and micronuclei data were assessed by analysis of covariance in the exposed and non-exposed groups. RESULTS: Multivariate analysis of covariance revealed that the frequencies of CBMN, nucleoplasmic bridge (NPB) and nuclear bud (NBUD) were significantly higher in BD exposed workers [(7.17 +/- 5.41) per thousand, (1.20 +/- 1.43) per thousand and (2.87 +/- 2.44) per thousand, respectively] than in the controls [(3.10 +/- 2.56) per thousand, (0.24 +/- 0.66) per thousand and (1.68 +/- 1.92) per thousand, P < 0.01, respectively]. Rank sum test revealed that in BD exposed workers, the XRCC4 A245G AA genotype exhibited higher NPB frequency than that of AG or GG genotypes significantly (P < 0.05). Stratification analysis showed that the polymorphism of XRCC4 T1394G TT carriers had significantly higher CBMN frequencies than those GG carriers (P < 0.01) in < 39 year workers. CONCLUSION: The results suggested that polymorphisms of XRCC4 A245G and T1394G could influence the chromosomal damage levels in BD exposed workers.

Effects of triptolide from Tripterygium wilfordii on ERalpha and p53 expression in two human breast cancer cell lines.

The aim of the study was to discover possible differential cytotoxicity of triptolide towards estrogen-sensitive MCF-7 versus estrogen-insensitive MDA-MB-231 human breast cancer cells. Considering that MCF-7 cells express functional Estrogen receptor alpha (ERalpha) and wild-type p53, whereas MDA-MB-231 cells which are ERalpha-negative express mutant p53, the anti-proliferation effect of triptolide on MCF-7 and MDA-MB-231 cells were examined, the apoptotic effect and cell cycle arrest caused by triptolide were investigated, ERalpha and p53 expression were also observed in this paper. The results showed that the anti-proliferation effects were induced by triptolide in both cell lines. But the value of IC(50) in MCF-7 cells for its anti-proliferation effect was about one tenth of that in MDA-MB-231 cells, which indicated that the effect is more potent in MCF-7 cells. Condensed chromatin or fragmented nuclei could be found in MCF-7 cells treated with only 40nM triptolide but in MDA-MB-231 cells they couldn't be observed until the concentration reached to 400nM. Triptolide induced significant S cell cycle arrest along with the presence of sub-G0/G1 peak in MDA-MB-231 cells, whereas there was only slightly S cell cycle arrest on cell cycle distribution in MCF-7 cells. The role of p53 in two breast cancer cells was examined, the results showed that the mutant p53 in MDA-MB-231 cells was suppressed and the wild-type p53 in MCF-7 was increased. Moreover, triptolide could down regulate the expression of ERalpha in MCF-7 cells. The results showed that triptolide is much more sensitive to ERalpha-positive MCF-7 cells than to ERalpha-negative MDA-MB-231 cells, and the sensitivity is significantly associated with the ERalpha and p53 status.

[Protective effect of reduced glutathione on cytotoxicity induced by hexavalent chromium [Cr(VI)] in L-02 hepatocyte].

OBJECTIVE: To explore the effect of reduced glutathione (GSH) on cytotoxicity induced by hexavalent chromium (Cr(VI)) in L-02 hepatocyte. METHODS: The test has three groups:the groups of (Cr(VI), the groups of GSH, the groups of Cr (VI) and GSH. The survival rate of L-02 hepatocyte is assessed on the reductions of tetrazolium dye (MTT). RESULTS: Significant cytotoxicities of L-02 hepatocyte were observed at the concenations of 2,4,8,16,32 and 64 micromol/L Cr (VI). Concentration-dependent decrease in cell survival rate of Cr (VI)-treated L-02 hepatocytes were observed (r = -0.910) Protective effect on all concentrations of Cr(VI) (2 - 64 micromol/L) at the dose of 20 micromol/LGSH were found. CONCLUSION: The results demonstrated that proper concentrations of GSH could have protective effect on cytoxicity induced by Cr(VI) in L-02 hepatocyte. GSH of too low or too high concentrations don't has this effect.