Ginkgolide A attenuated apoptosis via inhibition of oxidative stress in mice with traumatic brain injury.

Traumatic brain injury (TBI) is the main cause of death among young adults and the main cause of mortality and disability for all ages groups worldwide. Ginkgolides terpenoid compounds unique to Ginkgo biloba, which have protective effects on cardiovascular and cerebrovascular diseases. The aim of this study is to investigate whether ginkgolide A (GA) can improve TBI in mice and whether it can alleviate cell apoptosis in the brain of TBI mice by reducing oxidative stress. Mice received TBI and GA administration for 7 days. Neurological deficits were monitored and brain tissues were examined for molecular pathological markers. TBI mice had more severer neurobehavioral deficits compared with sham group, which could be improved by administration of GA. GA administration improveed Modified Neurological Severity Scale (mNSS) scores, Grid-Walking test and Rotarod test of TBI mice. The apoptosis increased in TBI mice, and reduced after GA treatment. The biomarkers of oxidative stress 8-OHdG and malondialdehyde (MDA) in the brain of TBI mice increased, while SOD reduced. These changes were reversed after GA administration. These outcomes showed that GA could raise neurobehavioral deficiency of TBI mice. GA treatment could attenuate apoptosis in TBI mice by reducing oxidative stress.

PoxCbh, a novel CENPB-type HTH domain protein, regulates cellulase and xylanase gene expression in Penicillium oxalicum.

The essential transcription factor PoxCxrA is required for cellulase and xylanase gene expression in the filamentous fungus Penicillium oxalicum that is potentially applied in biotechnological industry as a result of the existence of the integrated cellulolytic and xylolytic system. However, the regulatory mechanism of cellulase and xylanase gene expression specifically associated with PoxCxrA regulation in fungi is poorly understood. In this study, the novel regulator PoxCbh (POX06865), containing a centromere protein B-type helix-turn-helix domain, was identified through screening for the PoxCxrA regulon under Avicel induction and genetic analysis. The mutant ∆PoxCbh showed significant reduction in cellulase and xylanase production, ranging from 28.4% to 59.8%. Furthermore, PoxCbh was found to directly regulate the expression of important cellulase and xylanase genes, as well as the known regulatory genes PoxNsdD and POX02484, and its expression was directly controlled by PoxCxrA. The PoxCbh-binding DNA sequence in the promoter region of the cellobiohydrolase 1 gene cbh1 was identified. These results expand our understanding of the diverse roles of centromere protein B-like protein, the regulatory network of cellulase and xylanase gene expression, and regulatory mechanisms in fungi.

Involvement of phospholipase PLA2 in production of cellulase and xylanase by Penicillium oxalicum.

Phospholipases play vital roles in immune and inflammatory responses in mammals and plants; however, knowledge of phospholipase functions in fungi is limited. In this study, we investigated the effects of deleting predicted phospholipase genes on cellulase and xylanase production, and morphological phenotype, in Penicillium oxalicum. Individual deletion of nine of the ten predicted phospholipase genes resulted in alteration of cellulase and xylanase production, and the morphological phenotypes, to various degrees. The mutant ∆POX07277 lost 22.5 to 82.8% of cellulase (i.e., filter paper cellulase, carboxymethylcellulase, and p-nitrophenyl-ß-cellobiosidase) and xylanase production, whereas p-nitrophenyl-ß-glucopyranosidase production increased by 5.8-127.8 fold. POX07277 (P. oxalicum gene No. 07277) was predicted to encode phospholipase A2 and was found to negatively affect the sporulation of P. oxalicum. Comparative transcriptomic and quantitative reverse transcription-PCR analysis indicated that POX07277 dynamically affected the expression of cellulase and xylanase genes and the regulatory genes for fungal sporulation, under micro-crystalline cellulose induction. POX07277 was required for the expression of the known regulatory gene PoxCxrB (cellulolytic and xylanolytic regulator B in P. oxalicum), which is involved in cellulase and xylanase gene expression in P. oxalicum. Conversely, POX07277 expression was regulated by PoxCxrB. These findings will aid the understanding of phospholipase functions and provide novel insights into the mechanism of fungal cellulase and xylanase gene expression. KEY POINTS : • The roles of phospholipases were investigated in Penicillium oxalicum. • POX07277 (PLA2) is required for the expression of cellulase and xylanase genes. • PoxCxrB dynamically regulated POX07277 expression.

Pediatric patellar dislocation.

Acute patellar dislocation affects approximately 1:1000 healthy children 9-15 years of age, and up to 50% are at risk for recurrent dislocations. In adults the condition is associated with long-term complications, such as osteoarthritis and impairment of knee function. However, literature describing the outcome in a pediatric population is sparse. The present review article evaluates the long-term effects on knee function and cartilage quality after traumatic patellar dislocation in childhood, and also to evaluate the reliability of two clinical tests of medio-lateral knee position, in healthy children.

Differential transcriptomic profiling of filamentous fungus during solid-state and submerged fermentation and identification of an essential regulatory gene PoxMBF1 that directly regulated cellulase and xylanase gene expression.

BACKGROUND: Solid-state fermentation (SSF) mimics the natural decay environment of soil fungi and can be employed to investigate the production of plant biomass-degrading enzymes. However, knowledge on the transcriptional regulation of fungal genes during SSF remains limited. Herein, transcriptional profiling was performed on the filamentous fungus Penicillium oxalicum strain HP7-1 cultivated in medium containing wheat bran plus rice straw (WR) under SSF (WR_SSF) and submerged fermentation (WR_SmF; control) conditions. Novel key transcription factors (TFs) regulating fungal cellulase and xylanase gene expression during SSF were identified via comparative transcriptomic and genetic analyses. RESULTS: Expression of major cellulase genes was higher under WR_SSF condition than that under WR_SmF, but the expression of genes involved in the citric acid cycle was repressed under WR_SSF condition. Fifty-six candidate regulatory genes for cellulase production were screened out from transcriptomic profiling of P. oxalicum HP7-1 for knockout experiments in the parental strain ∆PoxKu70, resulting in 43 deletion mutants including 18 constructed in the previous studies. Enzyme activity assays revealed 14 novel regulatory genes involved in cellulase production in P. oxalicum during SSF. Remarkably, deletion of the essential regulatory gene PoxMBF1, encoding Multiprotein Bridging Factor 1, resulted in doubled cellulase and xylanase production at 2 days after induction during both SSF and SmF. PoxMBF1 dynamically and differentially regulated transcription of a subset of cellulase and xylanase genes during SSF and SmF, and conferred stress resistance. Importantly, PoxMBF1 bound specifically to the putative promoters of major cellulase and xylanase genes in vitro. CONCLUSIONS: We revealed differential transcriptional regulation of P. oxalicum during SSF and SmF, and identified PoxMBF1, a novel TF that directly regulates cellulase and xylanase gene expression during SSF and SmF. These findings expand our understanding of regulatory mechanisms of cellulase and xylanase gene expression during fungal fermentation.

How an essential Zn2Cys6 transcription factor PoxCxrA regulates cellulase gene expression in ascomycete fungi?

BACKGROUND: Soil ascomycete fungi produce plant-biomass-degrading enzymes to facilitate nutrient and energy uptake in response to exogenous stress. This is controlled by a complex signal network, but the regulatory mechanisms are poorly understood. An essential Zn2Cys6 transcription factor (TF) PoxCxrA was identified to be required for cellulase and xylanase production in Penicillium oxalicum. The genome-wide regulon and DNA binding sequences of PoxCxrA were further identified through RNA-Sequencing, DNase I footprinting experiments and in vitro electrophoretic mobility shift assays. Moreover, a minimal DNA-binding domain in PoxCxrA was recognised. RESULTS: A PoxCxrA regulon of 1970 members was identified in P. oxalicum, and it was displayed that PoxCxrA regulated the expression of genes encoding major plant cell wall-degrading enzymes, as well as important cellodextrin and/or glucose transporters. Interestingly, PoxCxrA positively regulated the expression of a known important TF PoxClrB. DNase I footprinting experiments and in vitro electrophoretic mobility shift assays further revealed that PoxCxrA directly bound the promoter regions of PoxClrB and a cellobiohydrolase gene cbh1 (POX05587/Cel7A-2) at different nucleic acid sequences. Remarkably, PoxCxrA autoregulated its own PoxCxrA gene expression. Additionally, a minimal 42-amino-acid PoxCxrA DNA-binding domain was identified. CONCLUSION: PoxCxrA could directly regulate the expression of cellulase genes and the regulatory gene PoxClrB via binding their promoters at different nucleic acid sequences. This work expands the diversity of DNA-binding motifs known to be recognised by Zn2Cys6 TFs, and demonstrates novel regulatory mechanisms of fungal cellulase gene expression.

The transcription factor TpRfx1 is an essential regulator of amylase and cellulase gene expression in Talaromyces pinophilus.

BACKGROUND: Perfect and low cost of fungal amylolytic and cellulolytic enzymes are prerequisite for the industrialization of plant biomass biorefinergy to biofuels. Genetic engineering of fungal strains based on regulatory network of transcriptional factors (TFs) and their targets is an efficient strategy to achieve the above described aim. Talaromyces pinophilus produces integrative amylolytic and cellulolytic enzymes; however, the regulatory mechanism associated with the expression of amylase and cellulase genes in T. pinophilus remains unclear. In this study, we screened for and identified novel TFs regulating amylase and/or cellulase gene expression in T. pinophilus 1-95 through comparative transcriptomic and genetic analyses. RESULTS: Comparative analysis of the transcriptomes from T. pinophilus 1-95 grown on media in the presence and absence of glucose or soluble starch as the sole carbon source screened 33 candidate TF-encoding genes that regulate amylase gene expression. Thirty of the 33 genes were successfully knocked out in the parental strain T. pinophilus ∆TpKu70, with seven of the deletion mutants firstly displaying significant changes in amylase production as compared with the parental strain. Among these, ∆TpRfx1 (TpRfx1: Talaromyces pinophilus Rfx1) showed the most significant decrease (81.5%) in amylase production, as well as a 57.7% reduction in filter paper cellulase production. Real-time quantitative reverse transcription PCR showed that TpRfx1 dynamically regulated the expression of major amylase and cellulase genes during cell growth, and in vitro electrophoretic mobility shift assay revealed that TpRfx1 bound the promoter regions of genes encoding α-amylase (TP04014/Amy13A), glucoamylase (TP09267/Amy15A), cellobiohydrolase (TP09412/cbh1), ß-glucosidase (TP05820/bgl1), and endo-ß-1,4-glucanase (TP08514/eg1). TpRfx1 protein containing a regulatory factor X (RFX) DNA-binding domain belongs to RFX family. CONCLUSION: We identified a novel RFX protein TpRFX1 that directly regulates the expression of amylase and cellulase genes in T. pinophilus, which provides new insights into the regulatory mechanism of fungal amylase and cellulase gene expression.

Overexpression of CD155 relates to metastasis and invasion in osteosarcoma.

The rapid development of metastatic lesions remains the leading cause of mortality for patients with osteosarcoma. CD155 serves a key role in cancer cell migration, invasion and metastasis. However, the function and mechanism of CD155 has not been explored in osteosarcoma metastasis. In the present study, we found that CD155 was significantly upregulated in lung metastatic tissue and the highly metastatic cell line K7M2-WT (K7M2) of osteosarcoma. Overexpression of CD155 in K7M2 cells enhanced lung metastasis, while inhibition of CD155 by an anti-CD155 monoclonal antibody reduced metastasis. Blocking of CD155 also decreased migration and invasion of K7M2 cells in vitro. A western blot analysis revealed that blocking of CD155 inhibits metastasis by downregulating focal adhesion kinase (FAK) and phosphorylated FAK (pFAK) in osteosarcoma. The results revealed that CD155 serves a crucial role in the metastasis of osteosarcoma by regulating FAK and may provide a novel molecular target for therapeutic intervention in metastatic osteosarcoma.

Pediatric skull fractures and intracranial injuries.

The determination of plausibility of an injury arising from a fall leading to head trauma is a great challenge especially in young children. The present review is aimed to discuss important developments in the filed of head trauma cases especially in children. We explored various studies pertaining to head trauma injuries in children by exploring mainly PubMed, Google scholar and some library periodicals available in our library. Studies in the recent past explored the head injuries as a result of a low height fall. However, there are great amount of difficulties in assessment of height with certainty that caused head injuries like skull fracture or intracranial injury. Biomechanical thresholds have been estimated for young children for injuries such as skull fracture, but they have not been assessed against the injuries observed in a clinical setting. So, this review discusses current aspects of pediatric head injuries ranging from a minor head injury to a skull fracture. The present review concludes that recording full details of cause of head trauma such as fall height is essential for proper treatment planning and efficient management.

Interleukin-24 inhibits osteosarcoma cell migration and invasion via the JNK/c-Jun signaling pathways.

Approximately 25% of osteosarcoma patients present with clinically detectable metastatic disease at the time of initial diagnosis. High-dose chemotherapy and/or surgery for the treatment of primary metastatic osteosarcoma is ineffective, and <20% of patients will survive 5 years from diagnosis. Therefore, the treatment of metastases is critical for the improvement of the prognosis of primary metastatic osteosarcoma patients. We have previously observed that overexpression of interleukin-24 (IL-24) inhibits neuroblastoma cell proliferation, migration and invasion in vitro. The present study investigated whether IL-24 may be a novel agent for osteosarcoma metastasis-suppressive treatment. It was observed that IL-24 is able to inhibit migration and invasion in spontaneously metastasizing human 143B osteosarcoma cells via the c-Jun N-terminal kinase (JNK)/c-Jun signaling pathway. IL-24 was effective in inhibiting JNK and c-Jun phosphorylation to downregulate matrix metalloproteinase (MMP)-2 and MMP-9, which contributed to the suppression of cell migration and invasion. It was concluded that IL-24 may be a potent agent in the inhibition of highly metastatic 143B osteosarcoma cells, and IL-24 may have translational potential as an effective therapeutic agent for the treatment of metastatic osteosarcoma.

PI3K/Akt signaling mediated Hexokinase-2 expression inhibits cell apoptosis and promotes tumor growth in pediatric osteosarcoma.

Accumulating evidence has shown that PI3K/Akt pathway is frequently hyperactivated in osteosarcoma (OS) and contributes to tumor initiation and progression. Altered phenotype of glucose metabolism is a key hallmark of cancer cells including OS. However, the relationship between PI3K/Akt pathway and glucose metabolism in OS remains largely unexplored. In this study, we showed that elevated Hexokinase-2 (HK2) expression, which catalyzes the first essential step of glucose metabolism by conversion of glucose into glucose-6-phosphate, was induced by activated PI3K/Akt signaling. Immunohistochemical analysis showed that HK2 was overexpressed in 83.3% (25/30) specimens detected and was closely correlated with Ki67, a cell proliferation index. Silencing of endogenous HK2 resulted in decreased aerobic glycolysis as demonstrated by reduced glucose consumption and lactate production. Inhibition of PI3K/Akt signaling also suppressed aerobic glycolysis and this effect can be reversed by reintroduction of HK2. Furthermore, knockdown of HK2 led to increased cell apoptosis and reduced ability of colony formation; meanwhile, these effects were blocked by 2-Deoxy-d-glucose (2-DG), a glycolysis inhibitor through its actions on hexokinase, indicating that HK2 functions in cell apoptosis and growth were mediated by altered aerobic glycolysis. Taken together, our study reveals a novel relationship between PI3K/Akt signaling and aerobic glycolysis and indicates that PI3K/Akt/HK2 might be potential therapeutic approaches for OS.