Biodegradable ferroelectric molecular crystal with large piezoelectric response.

Transient implantable piezoelectric materials are desirable for biosensing, drug delivery, tissue regeneration, and antimicrobial and tumor therapy. For use in the human body, they must show flexibility, biocompatibility, and biodegradability. These requirements are challenging for conventional inorganic piezoelectric oxides and piezoelectric polymers. We discovered high piezoelectricity in a molecular crystal HOCH2(CF2)3CH2OH [2,2,3,3,4,4-hexafluoropentane-1,5-diol (HFPD)] with a large piezoelectric coefficient d33 of ~138 picocoulombs per newton and piezoelectric voltage constant g33 of ~2450 × 10-3 volt-meters per newton under no poling conditions, which also exhibits good biocompatibility toward biological cells and desirable biodegradation and biosafety in physiological environments. HFPD can be composite with polyvinyl alcohol to form flexible piezoelectric films with a d33 of 34.3 picocoulombs per newton. Our material demonstrates the ability for molecular crystals to have attractive piezoelectric properties and should be of interest for applications in transient implantable electromechanical devices.

Optimization of Ultrasonic-Assisted Extraction of Total Flavonoids from Abrus Cantoniensis (Abriherba) by Response Surface Methodology and Evaluation of Its Anti-Inflammatory Effect.

Abrus cantoniensis is a Chinese herbal medicine with efficacy in clearing heat and detoxification, as well as relieving liver pain. The whole plant, except the seeds, can be used and consumed. Flavonoids have been found in modern pharmacological studies to have important biological activities, such as anti-inflammatory, antibacterial and antioxidant properties. The antibacterial and antioxidant bioactivities of the total flavonoids of Abrus cantoniensis (ATF) have been widely reported in national and international journals, but there are fewer studies on their anti-inflammatory effects. The present study focused on the optimization of the ultrasonic extraction process of ATF by response surface methodology and the study of its anti-inflammatory effects in vitro and in vivo. The results showed that the factors that had a great impact on the ATF extraction were the material-to-liquid ratio, ultrasonic extraction cycles and ethanol concentration. The best extraction process used a material-to-liquid ratio of 1:47, ultrasonic extraction cycles of 4 times, an ethanol concentration of 50%, an ultrasonic extraction time of 40 min and an ultrasonic power of 125 W. Under these conditions, the actual extraction rate of total flavonoids was 3.68%, which was not significantly different from the predicted value of 3.71%. In an in vitro anti-inflammatory assay, ATF was found to be effective in alleviating LPS (lipopolysaccharide)-induced inflammation in mouse peritoneal macrophages. In an in vivo anti-inflammatory assay, ATF was found to have a significant inhibitory effect on xylene-induced ear swelling in mice and cotton ball granuloma in mice, and the inhibitory effect was close to that of the positive control drug dexamethasone. This may provide a theoretical basis for the further development of the medicinal value of Abrus cantoniensis.

Growth differentiation factor 1-induced tumour plasticity provides a therapeutic window for immunotherapy in hepatocellular carcinoma.

Tumour lineage plasticity is an emerging hallmark of aggressive tumours. Tumour cells usually hijack developmental signalling pathways to gain cellular plasticity and evade therapeutic targeting. In the present study, the secreted protein growth and differentiation factor 1 (GDF1) is found to be closely associated with poor tumour differentiation. Overexpression of GDF1 suppresses cell proliferation but strongly enhances tumour dissemination and metastasis. Ectopic expression of GDF1 can induce the dedifferentiation of hepatocellular carcinoma (HCC) cells into their ancestral lineages and reactivate a broad panel of cancer testis antigens (CTAs), which further stimulate the immunogenicity of HCC cells to immune-based therapies. Mechanistic studies reveal that GDF1 functions through the Activin receptor-like kinase 7 (ALK7)-Mothers against decapentaplegic homolog 2/3 (SMAD2/3) signalling cascade and suppresses the epigenetic regulator Lysine specific demethylase 1 (LSD1) to boost CTA expression. GDF1-induced tumour lineage plasticity might be an Achilles heel for HCC immunotherapy. Inhibition of LSD1 based on GDF1 biomarker prescreening might widen the therapeutic window for immune checkpoint inhibitors in the clinic.

[Retracted] Daidzein exerts anticancer activity towards SKOV3 human ovarian cancer cells by inducing apoptosis and cell cycle arrest, and inhibiting the Raf/MEK/ERK cascade.

Following the publication of the above paper, a concerned reader drew to the Editor's attention that several figures contained data that bore striking similarities to data published in other papers; notably, the western blot data shown in Fig. 6 appeared to have been presented in other studies, notably in Fig. 7B of another paper published around the same time and written by different authors based at different research institutions [Li P, Zhang Z, Zhang F, Zhou H and Sun W: Effects of 3­tetrazolyl methyl­3­hydroxy­oxindole hybrid (THOH) on cell proliferation, apoptosis, and G2/M cell cycle arrest occurs by targeting platelet­derived growth factor D (PDGF­D) and the MEK/ERK signaling pathway in human lung cell lines SK­LU­1, A549, and A­427. Med Sci Monit 24: 4547­4554, 2018]. Furthermore, cellular images featured in Fig. 2A and B of the above paper appeared in Fig. 2 of the following paper, albeit the data were presented in a different field of view: Yu L, Zhou G­Q and Li D­C: MiR­136 triggers apoptosis in human gastric cancer cells by targeting AEG­1 and BCL2. Eur Rev Med Pharmacol Sci 22: 7251­7256, 2018. After having conducted an independent investigation in the Editorial Office, the Editor of International Journal of Molecular Medicine has determined that this article should be retracted from the Journal on account of a lack of confidence concerning the originality and the authenticity of the data. The authors were asked for an explanation to account for these concerns, but the Editorial Office never received any reply. The Editor regrets any inconvenience that has been caused to the readership of the Journal. [the original article was published on International Journal of Molecular Medicine 41, 3485-3492, 2018; DOI: 10.3892/ijmm.2018.3531].

Thymic Stromal Lymphopoietin-Related Allergic Pathway in Patients With Vernal Keratoconjunctivitis.

PURPOSE: To investigate the expression of thymic stromal lymphopoietin (TSLP) and the relevant signaling pathways in the giant papillae obtained from patients with vernal keratoconjunctivitis (VKC) and to study the potential functional role and molecular mechanism of TSLP. METHODS: Giant papillae from VKC patients and control samples were used to perform immunohistochemical staining and analyze the mRNA expression of TSLP and related pathway by real-time polymerase chain reaction. RESULTS: TSLP was markedly expressed in the epithelial cells and some inflammatory cells of giant papillae, but not in the control conjunctival tissue. TSLP mRNA expression in the giant papillae of VKC was increased by 9.63 ± 0.99 (mean ± SD) fold compared with controls (P < 0.01). CD11c and OX40L immunoreactive cells largely infiltrated the giant papillae as observed by immunohistochemical staining. CD4Th2 cell infiltration was observed through high immunoreactivity of CD4. Th2 cytokines (IL-4, IL-5 and IL-13) and OX40 in the VKC specimens showed increased expression. Augmented gene expression levels of CD4 (6.88 ± 1.84), OX40L (7.60 ± 1.79), OX40 (7.25 ± 1.38), IL-4 (6.89 ± 1.46), IL-5 (8.42 ± 1.55), and IL-13 (9.69 ± 1.94) were significantly different from controls (P < 0.05). CONCLUSIONS: Our observations provide strong evidence that TSLP may be a crucial factor that contributes to the development and progression of allergic conjunctivitis. The results also demonstrated that TSLP activates dendritic cells to prime CD4T cells to differentiate into Th2 type and triggers Th2-dominant allergic inflammation through the TSLP/OX40L/OX40 signaling as part of immunopathogenesis of VKC.

Zafirlukast in combination with pseudohypericin attenuates spinal cord injury and motor function in experimental mice.

BACKGROUND: Biosynthesis of leukotriene (LT) by arachidonic acid involves 5-lipoxygenase (5-LO) as an important precursor. Here, we evaluated the role of pseudohypericin (PHP) for its postulated 5-LO inhibitory activity along with a Cys-LT receptor antagonist zafirlukast (ZFL) against inflammatory response and tissue injury in mice. MATERIALS AND METHODS: The spinal injury was induced by two-level laminectomy of T6 and T7 vertebrae. The inflammation was assessed by histology, inflammatory mediators by enzyme-linked immunosorbent assay, apoptosis by Annexin-V, FAS staining, terminal deoxynucleoti-dyltransferase-mediated UTP end labeling (TUNEL) assay and expression of Bax and Bcl-2 by Western blot. Effect on motor recovery of hind limbs was evaluated for 10 days postinjury. RESULTS: The spinal injury resulted in tissue damage, apoptosis, edema, infiltration of neutrophils with increased expression of tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2). The spinal tissue showed elevated levels of prostaglandin E2 (PGE2), and LTB4 and increased phosphorylation of injured extracellular signal-regulated kinase-1/2 (ERK1/2). The PHP, ZFL and combination decreased inflammation, tissue injury and infiltration of neutrophils. Treatment also decreased the levels of PGE2, phosphorylation of extracellular signal-regulated kinase-1/2 (pERK 1/2), LT, TNF-α and COX-2 with a marked reduction in apoptosis and improved the motor function. CONCLUSION: The present study confirmed 5-LO antagonist activity of PHP and established its neuroprotective role along with ZFL.

Daidzein exerts anticancer activity towards SKOV3 human ovarian cancer cells by inducing apoptosis and cell cycle arrest, and inhibiting the Raf/MEK/ERK cascade.

Ovarian cancer is the main cause of gynecological cancer­associated mortality around the world. Despite initial responses to chemotherapy, frequent relapse occurs. Daidzein is an important flavonoid and has been shown to exhibit a diversity of pharmacological properties, including antimicrobial and anticancer activities. However, information on the anticancer activity of daidzein against ovarian cancer remains limited. Therefore, the present study evaluated the anticancer activity of daidzein against a panel of human ovarian cancer cell lines and one normal ovarian cell line (Moody). The results revealed that daidzein exhibited potent anticancer activity against SKVO3 cells with a half­maximal inhibitory concentration (IC50) of 20 µM. However, it exhibited comparatively lower activity against normal ovarian Moody cells, which had an IC50 of 100 µM. Daidzein induced morphological changes in SKOV3 cells and mitochondrial apoptosis, as evident from DAPI, AO/EB and Annexin V/propidium iodide staining. This was associated with the upregulation of B­cell lymphoma 2­associated X protein, cytochrome c, cleaved caspase­3 and ­9, and cleaved poly (ADP­ribose) polymerase. Daidzein also triggered G2/M cell arrest through the downregulation of pCdc25c, Cdc25c, pCdc2, Cdc2 and cyclin B1. The effect of daidzein on the migration of SKOV3 cells was also determined, the results of which indicated that daidzein inhibited cell migration in a concentration­dependent manner and was coupled with concomitant decrease in the expression of matrix metalloproteinase (MMP)­2 and ­9. Additionally, daidzein­inhibited cell growth was simultaneous with suppression of the expression of phosphorylated mitogen­activated protein kinase kinase and phosphorylated extracellular signal­regulated kinase. The present study also examined whether daidzein exerts similar activity against SKOV3 cells in nude mouse xenograft models and it was revealed that daidzein considerably reduced the tumorigenesis in vivo, indicative of the potential for daidzein as a lead molecule in the development of ovarian cancer chemotherapy.

Long Noncoding RNA CCAT2 Knockdown Suppresses Tumorous Progression by Sponging miR-424 in Epithelial Ovarian Cancer.

Epithelial ovarian cancer (EOC) is the one of most common gynecological malignant tumors with high mortality. A series of long noncoding RNAs (lncRNAs) have been validated to play a vital role in EOC tumorigenesis. Colon cancer-associated transcript 2 (CCAT2) has been verified as an oncogenic lncRNA in multiple tumors; however, the role of CCAT2 in EOC genesis is still unclear. The purpose of the present study was to probe the function of CCAT2 on EOC. Preliminary experiments found that CCAT2 expression was significantly upregulated in EOC tissues and cell lines compared to noncancerous tissue and cells. CCAT2 knockdown induced by interfering oligonucleotides could inhibit proliferation and promote apoptosis and induce cell cycle arrest at the G0/G1 phase. Bioinformatics analysis predicted that miR-424 targeted CCAT2, which was confirmed by luciferase reporter assay. Moreover, the miR-424 inhibitor rescued the tumorigenesis inhibition induced by CCAT2 knockdown. In summary, our findings illustrate that CCAT2 acts as competing endogenous RNA (ceRNA) or sponge via negatively targeting miR-424, providing a novel diagnostic marker and therapeutic target for EOC.

Abnormal DNA methylation may contribute to the progression of osteosarcoma.

The identification of optimal methylation biomarkers to achieve maximum diagnostic ability remains a challenge. The present study aimed to elucidate the potential molecular mechanisms underlying osteosarcoma (OS) using DNA methylation analysis. Based on the GSE36002 dataset obtained from the Gene Expression Omnibus database, differentially methylated genes were extracted between patients with OS and controls using t­tests. Subsequently, hierarchical clustering was performed to segregate the samples into two distinct clusters, OS and normal. Gene Ontology (GO) and pathway enrichment analyses for differentially methylated genes were performed using the Database for Annotation, Visualization and Integrated Discovery tool. A protein­protein interaction (PPI) network was established, followed by hub gene identification. Using the cut­off threshold of ≥0.2 average ß­value difference, 3,725 unique CpGs (2,862 genes) were identified to be differentially methylated between the OS and normal groups. Among these 2,862 genes, 510 genes were differentially hypermethylated and 2,352 were differentially hypomethylated. The differentially hypermethylated genes were primarily involved in 20 GO terms, and the top 3 terms were associated with potassium ion transport. For differentially hypomethylated genes, GO functions principally included passive transmembrane transporter activity, channel activity and metal ion transmembrane transporter activity. In addition, a total of 10 significant pathways were enriched by differentially hypomethylated genes; notably, neuroactive ligand­receptor interaction was the most significant pathway. Based on a connectivity degree >90, 7 hub genes were selected from the PPI network, including neuromedin U (NMU; degree=103) and NMU receptor 1 (NMUR1; degree=103). Functional terms (potassium ion transport, transmembrane transporter activity, and neuroactive ligand­receptor interaction) and hub genes (NMU and NMUR1) may serve as potential targets for the treatment and diagnosis of OS.

Phosphodiesterase inhibitor ameliorates neuronal injury in spinal cord ischemia/reperfusion injured rat model.

This study investigated the mechanisms responsible for the neuroprotective effect of sildenafil citrate (SFC) on ischemia-reperfusion spinal cord (SC) injuries. Balloon occlusion of the thoracic aorta was used to induce SC ischemia. The animals (n=30) were separated into three groups: sham, SC injury with saline, and SC injury with 5mg/kg i.p. SFC treatment (SFC). The Basso, Beattie, and Bresnahan (BBB) score was determined to assess neurological function at different time intervals after reperfusion. After 48h, histopathology of the SC was assessed by triphenyltetrazolium chloride (TTC) and Nissl staining. Myeloperoxidase (MPO) activity was estimated using an MPO assay kit. Western blot and ELISA assays were performed to estimate interleukin 1 & 10 (IL-1 & IL-10), tumour necrosis factor α (TNF-α), and nuclear factor (NF-kB) levels in SC tissue homogenates. The study results suggest that treatment with SFC significantly increased neurological function compared with the SC group. In addition, SFC treatment reduced MPO activity compared with the SC group, which subsequently inhibited the infiltration of neutrophils into the SC. There was a significant (p<0.01) decrease in the expression of IL-1 and TNF-α, and an increase in the expression of IL-10 in SFC tissue homogenates compared with SC tissues. Moreover, SFC treatment inhibited the activation of NF-kB in the SC after injury. This study shows that SFC exerts a neuroprotective effect on the SC after ischemia/reperfusion injury by attenuating inflammatory mediators.

MiR-34a and miR-203 Inhibit Survivin Expression to Control Cell Proliferation and Survival in Human Osteosarcoma Cells.

Elevated expression of survivin is observed in a number of cancer types, including human osteosarcoma. Few studies have demonstrated that survivin expression levels can be considered an independent predictor of survival for human osteosarcoma patients. However, the underlying molecular mechanisms of survivin in the process of human osteosarcoma carcinogenesis remain unclear. In the current study, we evaluated the biological effects of survivin knockdown on osteosarcoma cell proliferation, colony formation rate, and sensitivity to the chemotherapeutic agent cisplatin. We found that two different osteosarcoma cell lines, U2OS and Saos-2, have relatively higher expression levels of survivin, and specific knockdown of survivin resulted in a number of effects, such as inhibition of cell proliferation, decreased colony formation rate, cell cycle arrest at G2/M phase, induction of apoptosis, and increased sensitivity to cisplatin. In addition, we identified two microRNAs, miR-34a and miR-203, that are aberrantly expressed in human osteosarcoma cells and specifically target survivin by inhibiting its expression, therefore repressing osteosarcoma cell maintenance and proliferation.

Clostridium difficile carriage in hospitalized cancer patients: a prospective investigation in eastern China.

BACKGROUND: Clostridium difficile carriage has been considered as a potential source for the deadly infection, but its role in cancer patients is still unclear. We aimed to identify the clinical and immunological factors that are related to C. difficile carriage in Chinese cancer patients. METHODS: A total of 400 stool samples were collected from cancer patients who received chemotherapy in three hospitals of eastern China. Bacterial genomic DNA was extracted and two toxin genes (tcdA and tcdB) were detected. PCR ribotyping was performed using capillary gel electrophoresis. Concentrations of prostaglandin E2 (PGE2), transforming growth factor beta (TGF-ß) and interleukin-10 (IL-10) were measured using enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: Eighty-two (20.5%) samples were confirmed to be C. difficile-positive and positive for tpi, tcdA, and tcdB genes. The C. difficile-positive rates in patients with diarrhea and no diarrhea were 35% and 19.7%, respectively (p = 0.09). Patients who were younger than 50 years old and were hospitalized for at least 10 days had a C. difficile-positive rate as high as 35%. In contrast, patients who were older than 50 years old and were hospitalized for less than 10 days had a C. difficile-positive rate of only 12.7% (p = 0.0009). No association was found between C. difficile carriage and chemotherapy regimen, antibiotic drug use, or immunosuppressive mediators, such as prostaglandin E2 (PGE2), transforming growth factor beta (TGF-ß), or interleukin-10 (IL-10). Twelve ribotypes of C. difficile were identified, but none of them belonged to ribotype 027. CONCLUSIONS: We conclude that younger patients and those with longer hospitalization stays may be more prone to C. difficile carriage. Studies of larger populations are warranted to clarify the exact role of C. difficile carriage in hospitalized cancer patients in China.

Characterization of microRNAs expression profiling in one group of Chinese urothelial cell carcinoma identified by Solexa sequencing.

OBJECTIVE: The goal of this study was to extend the known repertoire of microRNAs (miRNAs) expressed in urothelial bladder cancer (BCa) of the Chinese population and further understand the molecular events of miRNAs underlying urothelial bladder tumorigenesis at the global genome level. MATERIALS AND METHODS: We separated well-characterized epithelial tumor cells from 20 moderately differentiated or poorly differentiated BCa specimens by laser capture microdissection (LCM) and pooled these cells of interest prior to RNA analysis. Ten normal bladder epithelia (NBE) samples were pooled as the control. After preparation of small RNAs library, the 2 samples were sequenced simultaneously by the next generation high through-put Solexa sequencing technology. RESULTS: We employed the next generation high through-put Solexa sequencing technology to clone and identify miRNAs in BCa and NBE, and generated 11,146,610, and 10,263,845 high quality sequence reads, respectively. According to the analysis of size distribution, 22 nt class was the most abundant group of small RNAs in the BCa. Likewise, the 20 and 22 nt sequences were significantly greater than shorter or longer sequences, and accounted for 59.55% of the total sequence number of NBE library. The whole-genome-scale data mining suggested that BCa and NBE libraries both contained multiple and heterogeneous small RNA species. On further analysis, the sequencing data revealed that different miRNAs showed clearly in-house differential expression levels in BCa and NBE and 74 miRNAs aberrantly expressed between BCa and NBE at the global genome level. We also predicted 13 novel miRNAs in both BCa and NBE libraries. CONCLUSIONS: Our results suggest that BCa miRNAs include a large proportion of conserved miRNAs and a set of non-conserved miRNAs with low expression levels. These known and newly identified miRNAs at the population level significantly enhance our knowledge of BCa miRNAs expression profiling and provide insights into miRNAs oncogenesis and oncotherapy in BCa. Further studies are necessary to elucidate the roles of miRNAs in urothelial bladder tumorigenesis and determine the potential of miRNAs as diagnostic and prognostic tools or therapeutic targets for BCa in the future.

[Survivin gene silencing inhibits the proliferation of human gastric cancer MGC-803 cells and enhances their sensitivity to celecoxib].

OBJECTIVE: To investigate the effect of small interfering RNA (siRNA)-mediated survivin knock-down on the proliferation of human gastric cancer MGC-803 cells and their sensitivity to celecoxib. METHODS: The siRNA against survivin was constructed and transfected into MGC-803 cells via Lipofectamine(TM) 2000. The expression of survivin in the transfected cells was detected by RT-PCR and Western blot, and flow cytometry was used to detect the cell cycle changes. The sensitivity of the cells to celecoxib after transfection was examined using MTT assay and clonogenic assay. RESULTS: The protein and mRNA levels of survivin in MGC-803 cells were decreased significantly after siRNA transfection, which also caused cell cycle arrest in G(0)/G(1) phase. The sensitivity of MGC-803 cells to celecoxib was significantly increased after siRNA transfection. CONCLUSION: siRNA-mediated survivin silencing causes growth suppression of MGC-803 cells and enhances their sensitivity to celecoxib in vitro.

[Study on rhGM-CSF as adjuvant in revaccination among adults of non-and hyporesponders to hepatitis B vaccine].

OBJECTIVE: To investigate the effect of recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF) as adjuvant on immune response in adults of non-and hyporesponders to hepatitis B vaccine. METHODS: Those who were once immunized with recombined yeast gene hepatitis B vaccine more than one standard scheme in two years and negative for hepatitis B markers were randomly sorted as group A and group B. 33 adults of group A were given hepatitis B vaccine 10 microg each time. The immune procedure was 0, 1 and 6 month. 34 adults of group B were given rhGM-CSF 300 microg for the first day, then 10 microg each time for routine immune. The blood samples were collected before the first injection and in 1, 2 and 8 months (T1, T2, T8) following the first injection to test Anti-HBs. RESULTS: Anti-HBs positive conversion rates of group A and B at T8 was 39.39% and 64.71% respectively (P = 0.038). Anti-HBs levels of group B at T1, T2, T8 were (113.85 +/- 198.56) mIU/ml, (312.40 +/- 349.44) mIU/ml, (427.74 +/- 411.58) mIU/ml (P = 0.001). There was significant difference between group A and B in T8 Anti-HBs levels (P = 0.010). CONCLUSION: Better immune response was found in the group of rhGM-CSF with hepatitis B vaccine. So rhGM-CSF can induce the immune respond to hepatitis B vaccine.

[The expression of Fas after fluid percussion brain injury in rats].

OBJECTIVE: To inquire into the pathologic diagnosis and the dating of injuries of light closed encephalon injury. METHODS: Wistar rats were hurt by fluid percussion, and were killed respectively at 15 min, 30 min, 1 h, 3 h, 6 h, 12 h, 1 d, 4 d, 7 d, and 14 d after injury. The expression of Fas in the cerebral cortex, thalamus, and hippocampi was detected by immunohistochemistry and the results were assessed by image analysis system. RESULTS: The results showed that the expression of Fas could be detected in thirty minutes after injury, and then it increased significantly in three hours, reached apex in twelve hours after injury, decreased gradually in four days after injury, and returned to normal in 14 days after injury. CONCLUSION: This research demonstrated that Fas-mediated apoptosis appeared not only around brain trauma but also in the brain tissue far away from the traumatic area. It indicted that Fas expression is a useful target for diagnosis of early brain injury and the regularity of Fas expression could be used as one of indications in deducing the time of brain injury.

[Expression of PDGF-B after fluid percussion brain injury in rats].

OBJECTIVE: To elucidate the changes of PDGF-B chain in the brain injured by fluid percussion. METHODS: The expression of PDGF-B protein was studied by immunohistochemistry and the results were assessed by image analysis system. RESULTS: Enhanced expression of PDGF-B protein induced by fluid percussion injury was seen at 1 h, and its marked up-regulation was noted at 4-7 days, and then the expression became decreased but it remained above the control levels till 14 days after injury. CONCLUSION: Fluid percussion brain injury induced expression of PDGF-B. The regular change pattern of PDGF-B level in time course seems to be of value in estimating the age of brain injury.

[A study of the expression of Fas after fluid percussion brain injury in rats].

OBJECTIVE: To study the pathologic diagnosis and the injury time estimation in light closed encephalon injury. METHODS: Mice were hurt by fluid percussion, and were killed at 15, 30 min, 1, 3 , 6, 12 h, 1, 4, 7, 14 d respectively after injury. The expression of Fas-L in the cerebral cortex, thalamus, and hippocampi was detected by immunohistochemistry and the results were assessed by image analysis system. RESULTS: It is showed that the expression of Fas-L could be detected in 1 h after injury, and increased significantly in three hours, and it reached apex 12 h after injury, and decreased gradually four days after injury, and returned normal 14 days after injury. CONCLUSION: This research demonstrated that Fas-L mediated apoptosis appeared not only around brain trauma but also in the brain tissue far away from the traumatic area. It indicted that the expression of Fas-L is a useful target for diagnosis of early brain injury; the regularity of Fas-L expression could be used as one of indication to date the time of brain injury.