Nano-energy interference: A novel strategy for blunting tumor adaptation and metastasis

Blunting the tumor's stress-sensing ability is an effective strategy for controlling tumor adaptive survival and metastasis. Here, we have designed a cyclically amplified nano-energy interference device based on lipid nanoparticles (LNP), focused on altering cellular energy metabolism. This innovative nano device efficiently targets and monitors the tumor's status while simultaneously inhibiting mitochondrial respiration, biogenesis and ribosome production. To this end, we first identified azelaic acid (AA), a binary acid capable of disrupting the mitochondrial respiratory chain. Upon encapsulation in LNP and linkage to mitochondrial-targeting molecules, this disruptive effect is further augmented. Consequently, tumors exhibit a substantial upregulation of the glycolytic pathway, intensifying their glucose demand and worsening the tumor's energy-deprived microenvironment. Then, the glucose analog, 2-Deoxy-D-glucose (2-DG), linked to the LNP, efficiently targets tumors and competitively inhibits the tumor's normal glucose uptake. The synergetic results of combining AA with 2-DG induce comprehensive energy deficiency within tumors, blocking the generation of energy-sensitive ribosomes. Ultimately, the disruption of both mitochondria and ribosomes depletes energy supply and new protein-generating capacity, weakening tumor's ability to adapt to environmental stress and thereby inhibiting growth and metastasis. Comprehensively, this nano-energy interference device, by controlling the tumor's stress-sensing ability, provides a novel therapeutic strategy for refractory tumors.

Quantitative microbiological risk assessments for Salmonella spp. contaminated taiwanese salty chicken in the taiwanese population

The aim of the study is to develop Salmonella spp. Quantitative microbial risk assessments (QMRA) and to evaluate the risk of Salmonellosis illness in the Taiwanese population after consumption of Taiwanese salty chicken (TSC). We assume that Salmonella spp. May contaminate the fresh raw chicken used in TSC. After transport to the diner, fresh raw chicken is received, cleaned, and surface-washed by diner staff. The TSC is then cooked and sold to consumers. We set four different cross-contamination scenarios to evaluate the contamination level of Salmonella spp. In TSC. We used a Monte Carlo simulation method, a probabilistic analysis method, and exceedance risk to evaluate the risk of Salmonellosis illness. When the exceedance risk was 5 %, and taking the Taiwanese population above 19 years old as an example, the rate of contracting Salmonellosis from the consumption of TSC will be 2.94 % (2.94 million per 100 million people) if the chef does not clean their hands, knives, or cutting boards. However, if the chef washes their hands, knives, and cutting boards with cold water and soap, the illness rate of Salmonellosis from consuming TSC will be 1.93E-04 % (193 per 100 million people). Sensitivity analysis indicates that the most important risk factor in the QMRAs of TSC is the temperature of the fresh raw chicken during transportation, following which were the Salmonella spp. Residual. If the staff of the diner separates the cooking tools used for raw ingredients and those for cooked food, the illness risk of Salmonellosis will be very low.

From cradle to grave? A global hotspot and new species of the genus Lobaria discovered in the Himalayas and the Hengduan Mountains

In this study, the East Asian diversity of green-algal Lobaria was evaluated by applying both morphological and phylogenetic approaches. A multi-locus phylogenetic analysis of 72 green-algal Lobaria specimens was performed using a three-locus and time-calibrated species-tree approach. The analyses demonstrate that pairs of sexually and vegetatively reproducing lineages split into highly supported monophyletic clades. Taxonomically, 11 green-algal Lobaria species were identified as new to science, while 10 were previously described species. The species differentiated during the Pliocene and Pleistocene. The coincidence of paleoclimatic events with estimated dates of divergence support a bioclimatic hypothesis for species evolution in the green-algal Lobaria. Molecular phylogenies, a summary of diversity, detailed new species descriptions and geographical analyses are provided. Special recognition of species with a long evolutionary history, which merit high conservation priority, will be critical for preserving geographically restricted endemics in the Himalayas and the Hengduan Mountains, where habitat loss is driving rapid declines.

Perioperative respiratory muscle training improves respiratory muscle strength and physical activity of patients receiving lung surgery: A meta-analysis

BACKGROUND

The clinical role of perioperative respiratory muscle training (RMT), including inspiratory muscle training (IMT) and expiratory muscle training (EMT) in patients undergoing pulmonary surgery remains unclear up to now.

AIM

To evaluate whether perioperative RMT is effective in improving postoperative outcomes such as the respiratory muscle strength and physical activity level of patients receiving lung surgery.

METHODS

The PubMed, EMBASE (via OVID), Web of Science, Cochrane Library and Physiotherapy Evidence Database (PEDro) were systematically searched to obtain eligible randomized controlled trials (RCTs). Primary outcome was postoperative respiratory muscle strength expressed as the maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). Secondary outcomes were physical activity, exercise capacity, including the 6-min walking distance and peak oxygen consumption during the cardio-pulmonary exercise test, pulmonary function and the quality of life.

RESULTS

Seven studies involving 240 participants were included in this systematic review and meta-analysis. Among them, four studies focused on IMT and the other three studies focused on RMT, one of which included IMT, EMT and also combined RMT (IMT-EMT-RMT). Three studies applied the intervention postoperative, one study preoperative and the other three studies included both pre- and postoperative training. For primary outcomes, the pooled results indicated that perioperative RMT improved the postoperative MIP (mean = 8.13 cmH₂O, 95%CI: 1.31 to 14.95, P = 0.02) and tended to increase MEP (mean = 13.51 cmH₂O, 95%CI: -4.47 to 31.48, P = 0.14). For secondary outcomes, perioperative RMT enhanced postoperative physical activity significantly (P = 0.006) and a trend of improved postoperative pulmonary function was observed.

CONCLUSION

Perioperative RMT enhanced postoperative respiratory muscle strength and physical activity level of patients receiving lung surgery. However, RCTs with large samples are needed to evaluate effects of perioperative RMT on postoperative outcomes in patients undergoing lung surgery.

Taurine Reduces Liver Damage in Non-Alcoholic Fatty Liver Disease Model in Rats by Down-Regulating IL-9 and Tumor Growth Factor TGF-β

The study employed a rat model to examine the effects of taurine (Tau) on prevention and therapy of non-alcoholic fatty liver disease (NAFLD). In model rats maintained on a high-fat diet (HFD), the serum levels of ALT, AST, triglycerides, cholesterol, and LDL were higher than the corresponding levels in normal control and NP groups (p<0.05). In Tau-prevention and Tau-treatment groups, the serum levels of AST and triglycerides were lower than in HFD rats (p<0.05). In HFD rats, diffuse fatty degeneration and infiltration with inflammatory cells was observed in the liver; in the ileal mucosa, the villi were fractured or absent, the epithelium was exfoliated and infiltrated with inflammatory cells. The levels of TGF-β, IL-9, and their mRNA in the liver and ileal mucosa of HFD rats were significantly higher than in normal control and NP groups (p<0.05). In Tau-prevention and Tau-treatment groups, these levels were significantly lower than in HFD rats (p<0.05). Thus, TGF-β and IL-9 can be implicated in NAFLD genesis, while Tau can preventively or therapeutically diminish the damage to the liver and ileal mucosa in rats with this disease by down-regulating the expression of TGF-β and IL-9.

[Advances in research of pyroptosis in the mechanism of periodontal disease]

Pyroptosis is a pro-inflammatory form of programmed cell death that has been gradually recognized in recent years. It plays an important role in recognizing the invasion of exogenous pathogens and sensing endogenous danger signals. The initiation of pyroptosis depends on the activation of intracellular inflammasome and its downstream caspases, as well as the active fragment of the key protein Gasdermin. The invasion of periodontal pathogens induces an inflammatory response of the host, involving the activation of inflammasome and triggering pyroptosis as well. Meanwhile, it leads to the release of a large number of inflammatory cytokines such as interleukin (IL)-1β and IL-18 to amplify the inflammatory response and mediate periodontal tissue destruction eventually. This article reviews the research progress of the signaling pathways of pyroptosis, as well as its mechanism induced by periodontal pathogens and the mechanism of periodontal tissue damage in periodontitis in order to provide new targets and ideas for the prevention and treatment of periodontitis.

Downregulation of PDGF-D Inhibits Proliferation and Invasion in Breast Cancer MDA-MB-231 Cells

BACKGROUND

The platelet derived growth factor-D (PDGF-D) plays an important role in breast tumor aggressiveness. However, limited study has investigated the effect of silencing PDGF-D on the biological function of breast cancer. The purpose of this study is to clarify the potential value of PDGF-D as a target for breast cancer treatment.

METHODS

Reverse transcription-polymerase chain reaction and western blot were used to detect PDGF-D expression in 5 different breast cancer cells. The lentiviral vector was usd to silence PDGF-D in MDA-MB-231 cells. Then, Methyl Thiazolyl Tetrazolium was used to detect cell viability, 5-Ethynyl-2'- deoxyuridine and a soft agar assay were used to detect cell proliferation and clonality. Additionally, cell apoptosis after PDGF-D knockdown was measured by Annexin V/ Prodium Iodide staining, and cell migration was detected by trans-well assay. Survival rate and tumor size were measured by nude mice transplantation.

RESULTS

The MDA-MB-231 and SK-BR-3 cell lines showed higher PDGF-D expression than the MCF7 cell lines (P<.05). After the PDGF-D gene was silenced, the growth and colony forming abilitys ignificantly decreased (P<.05) together with the induction of apoptosis in MDA-MB-231 cells (P<.05). Moreover, MDA-MB-231 cells with PDGF-D silencing showed significantly diminished aggressive migration and invasion potential compared to other cells (P<.05). In vivo experiments also indicated that PDGF-D silencing inhibited tumor growth and improved the survival rate of tumor-bearing mice.

CONCLUSION

Downregulation of PDGF-D had dramatic effects on breast cancer cell proliferation, apoptosis and migration, which indicates that it plays an important role in breast cancer development and progression.

[Assessment of schistosomiasis transmission risk in Nanjian County of Yunnan Province in 2019]

OBJECTIVE

To assess the schistosomiasis transmission risk in Nanjing County, so as to provide the scientific evidence for the development of the schistosomiasis control strategy and consolidation of the control achievements.

METHODS

On May 2019, the Deqiu Village in Deqiu Town and Baiyun Village in Nanjing Town of Yunnan Province, where schistosomiasis were historically relatively highly endemic, were selected to assess the risk of transmission of schistosomiasis by means of a retrospective review of the data pertaining to the historical endemic situation and schistosomiasis control, combined with a cross-sectional survey of snail and wild feces distribution.

RESULTS

During the period between 2017 and 2018, the mean sero-prevalence rates of Schistosoma japonicum infections were 6.76% (202/2 990) and 2.86% (142/4 971) in humans and 0 (0/1 160) and 10.65% (31/291) in bovines in Deqiu and Baiyun villages of Nanjian County, respectively; however, no egg-positives were identified; in addition, there were 21.06 hm² snail habitats found, but no S. japonicum infections were detected in snails. In 2019, there was 6.17 hm² snail habitats detected, with 2.17% (245/11 298) occurrence of frames with snails and a 0.06 snails/0.1 m² density of living snails; however, no positives for nucleic acid detection were seen in snails; among the 136 wild fecal samples captures from 23 settings, no S. japonicum infections were identified.

CONCLUSIONS

The risk of schistosomiasis transmission remains at a low level in Nanjian County; however, the factors affecting the transmission of schistosomiasis have not been completed eliminated. The integrated schistosomiasis control strategy with an emphasis on the control of the source of S. japonicum infections requires to be reinforced to consolidate the control achievements.

Voxel-wise meta-analysis of structural changes in gray matter of Parkinson's disease patients with mild cognitive impairment

Evidence from previous voxel-based morphometry (VBM) studies indicates that widespread brain regions are involved in Parkinson’s disease with mild cognitive impairment (PD-MCI). However, the spatial localization reported for gray matter (GM) abnormalities is heterogeneous. The aim of the present study was to quantitatively integrate studies on GM abnormalities observed in PD-MCI in order to determine whether a pattern exists. Eligible whole-brain VBM studies were identified by a systematic search of articles in PubMed and EMBASE databases spanning from 1995 to January 1, 2019. A meta-analysis was performed to investigate regional GM abnormalities in PD-MCI. The anisotropic effect size version of seed-based d mapping (AES-SDM) meta-analysis was conducted to explore the GMV differences of PD-MCI compared with PD patients with normal cognitive function (PD-NC). A total of 12 studies comprising 243 PD-MCI patients and 326 PD-NC were included in the meta-analysis. PD-MCI patients showed a robust GM decrease in the left insula and left superior temporal gyrus. Moreover, meta-regression analysis demonstrated that age, PD duration and stage, and Unified Parkinson’s Disease Rating Scale III and Mini-Mental State Examination scores might be partly correlated with the GM abnormalities observed in PD-MCI patients. The convergent findings of this quantitative meta-analysis revealed a characteristic neuroanatomical pattern in PD-MCI. The findings provide some evidence that MCI in PD may result in the breakdown of the insula and temporal gyrus, which may serve as specific regions of interest for further investigations.

[Effect of different support angles on the fitness of removable partial denture framework fabricated using selective laser melting technique]

Objective: To evaluate the fitness of bilateral free-end dentition defect removable partial denture framework fabricated by selective laser melting (SLM) technique with different support angles. Methods: After the control group has been set to eliminate the system error, and according to the standard model of bilateral mandibular posterior teeth loss, eighteen titanium alloy removable partial denture frameworks fabricated by SLM technology were divided into 3 groups with support angles of 0° (horizontal group), 45°(45° group) and 90° (vertical group). Plaster cast with duplicated structure of tissue surface of the removable partial denture (RPD) framework was obtained. A three-dimensional scanner was used to scan original and duplicated plaster casts. The gaps between framework and the model in different parts were analyzed using Geomagic Qualify software to evaluate the fitness of the framework with visual method. Results: The framework fits on the plaster model completely, and its tissue surface fitted on the plaster model well. The deviation between frameworks and plaster casts was calculated as follow: the total deviations of the horizontal, 45°, and vertical group were (0.146±0.017), (0.182±0.015) and (0.185±0.022) mm respectively. The mean deviation of the horizontal group was significantly less than those of the 45° group and the vertical group (P<0.05). Moreover, there was no significant difference in the total deviation between the 45° group and the vertical group. The total deviation of occlusal rest of the horizontal group was significantly less than that of the 45° group (P<0.05). However, no significant difference was detected in the deviation of occlusal rest among the vertical group, the horizontal group, and the 45° group (P>0.05). There was no significant difference in the deviation of occlusal rest among the vertical group, the horizontal group, and the 45° group. The deviation of clasp of the horizontal group was significantly smaller than those of the 45° group and the vertical group (P<0.05). Whereas, there was no significant difference in the deviation of clasp between the 45° group and the 90° group (P>0.05). No significant difference was found in the deviation of lingual bar among the three groups (P>0.05). Conclusions: Among the three kinds of bilateral free-end dentition defect RPD framework fabricated by SLM in different support angles, horizontal printing was proved to reach the minimal deviation, even though the fitness of all three kinds of frameworks can fullfil clinical requirements according to previous studies.

[Long-term stability of periodontal root coverage procedures for gingival recession]

Gingival recession could result in root exposure, dental hypersensitivity and poor aesthetics. It has been demonstrated that varieties of root coverage procedures can significantly improve gingival recession in short-term (≤6 months), of which coronally advanced flap combined with connective tissue graft is the gold standard technique for treatment of gingival recession. It could obtain the optimally complete root coverage and maintain long-term stability (≥2 years). However, clinical knowledge about the long-term effectiveness of the other alternative graft materials remain very limited. Based on the existing clinical evidence, this article reviews coronally advanced flap, coronally advanced flap combined with connective tissue graft or alternative graft materials, with particular attention to the long-term stability of them, in order to provide reference for the design of further clinical trials and the plan of clinical treatments.

[Role of TNF-α in vascular remodeling in rats with chronic thromboembolic pulmonary hypertension]

Objective: To analyze the relationship between TNF-α and pulmonary vascular remodeling in order to explore the pathogenesis of CTEPH. Methods: Autologous blood clots were repeatedly injected into the left jugular vein of rats to establish the CTEPH model. Then mean pulmonary artery pressure (mPAP), histopathology, the plasma level of TNF-α, and the expressions of mRNA and protein of TNF-α in pulmonary artery were measured. Results: In the experiment group, the mPAP and vessel wall area/total area (WA/TA) ratio gradually increased as emblism extended, and increased significantly compared with the sham operation group. The plasma TNF-α concentration in the experimental group increased significantly (P<0.05). The TNF-α proteins expressed in pulmonary artery in the 1-week, 2-week, and 4-week subgroups of experimental group increased significantly compared with the sham operation group (1.62±0.08 vs 0.85±0.12, P<0.05; 1.85±0.08 vs 0.89±0.13, P<0.05; 1.37±0.12 vs 0.91±0.15, P<0.05, respectively). Immunohistochemical results showed that TNF-α expression was higher in pulmonary artery endothelial cells of the experimental group compared with the sham operation group. The expression of pulmonary artery TNF-α protein was positively related with mPAP (r=0.605, P<0.01), and with WA/TA (r=0.629, P<0.01). The expression of serum TNF-α was positively related with that of pulmonary artery TNF-α protein (r=0.721, P<0.01). Conclusion: A rat model of CTEPH can be established by repeatedly introducing autologous blood clots into the pulmonary artery with injecting TXA. Thrombosis induced higher expression of TNF-α in pulmonary arterial endothelial cells, and released into the blood. TNF-α may play an important role in the development of CTEPH, especially by contributing to vascular remodeling and PH.

Efficacy, acceptability, and tolerability of antidepressant treatments for patients with post-stroke depression: a network meta-analysis

The aim of this study was to investigate the efficacy, acceptability, and tolerability of antidepressants in treating post-stroke depression (PSD) by performing a network meta-analysis of randomized controlled trials of the current literature. Eligible studies were retrieved from online databases, and relevant data were extracted. The primary outcome was efficacy as measured by the mean change in overall depressive symptoms. Secondary outcomes included discontinued treatment for any reason and specifically due to adverse events. Fourteen trials were eligible, which included 949 participants and 9 antidepressant treatments. Few significant differences were found for all outcomes. For the primary outcome, doxepin, paroxetine, and nortriptyline were significantly more effective than a placebo [standardized mean differences: −1.93 (95%CI=−3.56 to −0.29), −1.39 (95%CI=−2.59 to −0.21), and −1.25 (95%CI=−2.46 to −0.04), respectively]. Insufficient evidence exists to select a preferred antidepressant for treating patients with post-stroke depression, and our study provides little evidence that paroxetine may be the potential choice when starting treatment for PSD. Future studies with paroxetine and larger sample sizes, multiple medical centers, and sufficient intervention durations is needed for improving the current evidence.

[A preliminary discussion on the contents and value of Shi er mai (Twelve Channels) and Bie mai (Allo-channels), the medical bamboo slips unearthed from Han tomb in Laoguanshan of Chengdu]

The 52 medical bamboo slips entitled Si er ma (Twelve Channels) and Bie mai (Allo-channels) , unearthed from Han tomb in Laoguanshan, are the exclusive medical books concerning channels. Shi er mai is the first work bearing the term " heart dominating channel" , and the running pathways and manifestations of 12 channels. This book could be the major original sources of the 12-channel theories described in the Chapter of Jing mai (Channels) of Ling shu (Miraculous Pivot) . While Bie mai suggests the coexistence of the multi-channel systems at the time when the book was compiled and, together with the 12 "channel" , and 3 "branched collaterals" , these 2 books represent the original condition before the establishment of the mode of channel circulation in Ling shu, and is significant to explore the nature and origin of channel.

Effects of perinatal exposure to nonylphenol on delivery outcomes of pregnant rats and inflammatory hepatic injury in newborn rats

The current study aimed to investigate the effects of perinatal exposure to nonylphenol (NP) on delivery outcome of pregnant rats and subsequent inflammatory hepatic injury in newborn rats. The pregnant rats were divided into 2 groups: control group (corn oil) and NP exposure group. Thirty-four pregnant rats were administered NP or corn oil by gavage from the sixth day of pregnancy to 21 days postpartum, with blood samples collected at 12 and 21 days of pregnancy and 60 days after delivery. The NP concentration was measured by HPLC, with chemiluminescence used for detection of estrogen and progesterone levels. Maternal delivery parameters were also observed. Liver and blood of the newborn rats were collected and subjected to automatic biochemical detection of liver function and blood lipid analyzer (immunoturbidimetry), and ultrastructural observation of the hepatic microstructure, with the TNF-α and IL-1β hepatic tissue levels evaluated by immunohistochemistry. Compared with the control group, the pregnant and postpartum serum NP and estradiol levels of the mother rats in the NP group were significantly increased, together with lowered progesterone level, increased number of threatened abortion and dystocia, and fewer newborn rats and lower litter weight. Serum and hepatic NP levels of the newborn rats measured 60 days after birth were significantly higher than those of the control group, as well as lower testosterone levels and increased estradiol levels. When observed under electron microscope, the hepatocyte nuclei of the control group were large and round, with evenly distributed chromatin. The chromatin of hepatocytes in the NP group presented deep staining of the nuclei, significant lipid decrease in the cytoplasm, and the majority of cells bonded with lysate. The results of immunohistochemistry showed that there was almost no TNF-α or IL-1β expression in the hepatocytes of the control group, while the number of TNF-α-, PCNA-, and IL-1β-positive cells in the NP group was increased, with higher integral optical density than the control group. Compared to the control group, the serum levels of alanine aminotransferase, aspartate aminotransferase, triglyceride and low-density lipoprotein in the newborn rats of the NP group were significantly increased. There was no significant difference in the serum level of high-density lipoprotein or cholesterol between the groups. Perinatal exposure to NP can interfere with the in vivo estrogen and progesterone levels of pregnant rats, resulting in threatened abortion, dystocia and other adverse delivery outcomes. High liver and serum NP levels of the newborn rats led to alteration of liver tissue structure and function. The NP-induced hepatotoxicity is probably mediated by inflammatory cytokines TNF-α and IL-1α.

[A preliminary evaluation and discussion on the significance of the medical bamboo slips Ci shu (Needling Methods) unearthed from a Han tomb in the Mount. Laoguan, Chengdu]

The compilation of medical bamboo slips, Ci shu(Needling Methods), which was unearthed from a Han tomb in Mt. Laoguan, is a monograph dealing exclusively with the principles of clinical acupuncture manipulations with 40 acupuncture prescriptions, being the earliest unearthed work with documented standard methods of acupuncture manipulations and acupuncture prescriptions in China. The chapter Zhen fang (Acupuncture Prescriptions) is the earliest summary of standardized acupoint prescriptions up to now in China, which is of great significance to clinical practice directly derived from ancient clinical performance of acupuncture. The chapter Zhen fang of the book Ci shu is also one of the earliest ancient clinical reports archiving the acupoint. This may provide invaluable perspectives to the study of the conceptualization, origination, development, formation of theoretical system, and clinical application of acupoints.

Overexpression of gelsolin reduces the proliferation and invasion of colon carcinoma cells

The enhanced motility of cancer cells via the remodeling of the actin cytoskeleton is crucial in the process of cancer cell invasion and metastasis. It was previously demonstrated that gelsolin (GSN) may be involved as a tumor or a metastasis suppressor, depending on the cell lines and model systems used. In the present study, the effect of GSN on the growth and invasion of human colon carcinoma (CC) cells was investigated using reverse transcription quantitative polymerase chain reaction and western blotting. It was observed that upregulation of the expression of GSN in human CC cells significantly reduced the invasiveness of these cells. The expression levels of GSN were observed to be reduced in CC cells, and the reduced expression level of GSN was often associated with a poorer metastasis-free survival rate in patients with CC (P=0.04). In addition, the overexpression of GSN inhibited the invasion of CC cells in vitro. Furthermore, GSN was observed to inhibit signal transducer and activator of transcription (STAT) 3 signaling in CC cells. Together, these results suggested that GSN is critical in regulating cytoskeletal events and inhibits the invasive and/or metastatic potential of CC cells. The results obtained in the present study may improve understanding of the functional and mechanistic links between GSN as a possible tumor suppressor and the STAT3 signaling pathway, with respect to the aggressive nature of CC. In addition, the present study demonstrated the importance of GSN in regulating the invasion and metastasis of CC cells at the molecular level, suggesting that GSN may be a potential predictor of prognosis and treatment success in CC.

Bacillus amyloliquefaciens supplementation alleviates immunological stress in lipopolysaccharide-challenged broilers at early age

This study was conducted to investigate the effect of Bacillus amyloliquefaciens ( BA: ) on the immune function of broilers challenged with lipopolysaccharide ( LPS: ). 192 one-day-old male Arbor Acre broiler chickens were randomly distributed into four treatments: 1) broilers fed a basal diet; 2) broilers fed a basal diet supplemented with BA; 3) LPS-challenged broilers fed a basal diet; and 4) LPS-challenged broilers fed a basal diet supplemented with BA. Each treatment consisted of six replicates with eight broilers per replicate. Broilers were intraperitoneally injected with either 500 μg LPS per kg body weight or sterile saline at 16, 18 and 20 d of age. LPS decreased the average daily gain ( ADG: , P = 0.001) and average daily feed intake (P = 0.001). The decreased ADG (P = 0.009) and increased feed conversion ratio (P = 0.047) in LPS-challenged broilers were alleviated by BA. LPS increased the relative spleen weight (P = 0.001). Relative spleen (P = 0.014) and bursa (P = 0.024) weights in the LPS-challenged broilers were reduced by BA. LPS increased white blood cell ( WBC: ) numbers (P = 0.001). However, the WBC numbers (P = 0.042) and the ratio of lymphocytes to WBC (P = 0.020) in LPS-challenged broilers were decreased with BA treatment. LPS decreased plasma lysozyme activity (P = 0.001), but increased concentrations of plasma corticosterone (P = 0.012) and IL-2 (P = 0.020). In contrast, BA increased lysozyme activity in plasma (P = 0.040). LPS increased mRNA abundances of splenic toll-like receptor 4 (P = 0.046), interferon γ (P = 0.008), IL-1β (P = 0.045) and IL-6, (P = 0.006). IL-2 (P = 0.014) and IL-6 (P = 0.074) mRNA abundances in LPS-challenged broilers were reduced by BA, although BA had an opposite effect for IL-10 mRNA expression in those broilers (P = 0.004). In conclusion, BA supplementation could partially alleviate the compromised growth performance and immune status of broilers under immune stress induced by LPS challenge at early age.

The efficacy of fibrin sealant in knee surgery: A meta-analysis

BACKGROUND

Fibrin sealant is frequently used in knee surgery as an adjuvant method for reducing postoperative bleeding, however, there is no consensus regarding the efficacy of fibrin sealant.

HYPOTHESIS

Fibrin sealant achieves better efficacy in terms of blood loss control, transfusion rate and units in knee surgery compared with controls.

METHODS

A search of the Cochrane Collaboration (2013 Issue 09), Embase (1974-2013.09), PubMed (1966-2013.09) and Chinese databases (up to 2013.09) were conducted. The Cochrane Collaboration's tool was used to assess for bias and data were analyzed by RevMan 5.29 software.

RESULTS

This study included nine RCTs and four prospective comparative trials with a total of 1299 patients. Compared to the control, fibrin sealant achieved a decrease in hemoglobin reduction [MD=1.14, 95% CI (0.61-1.67)], transfusion rate [OR=0.36, 95% CI (0.25-0.51)], transfusion units [MD=0.47, 95% CI (0.24-0.71)], hospital stay [MD=2.22, 95% CI (0.56-3.88)] and the incidence of complications [OR=0.56, 95% CI (0.38-0.83)]. And it also reduced total blood loss, while there was no significant difference [MD=155.83, 95% CI (-525.02-213.15)].

CONCLUSION

Patients undergoing knee surgery would benefit from high-dose fibrin sealant with reduced transfusion rate and unit, hospital stay and complications, while they might benefit little from it in total blood loss. However, the effects of a low-dose of fibrin in knee surgery remain inconclusive.

P2-01-21: The Biological Influence of Brain Derived Neurotrophic Factor (BDNF) on the Aggressiveness of Human Breast Cancer Cells

Introduction: Brain derived neurotrophic factor (BDNF) is a member of the neurotrophin superfamily and has been indicated in the pathophysiology of the nervous system and is important in a number of neurological and psychological conditions. Recently, BDNF has also been shown to play a role in the development and progression of solid tumours myeloma, lung cancer and prostate cancer. It has been recently reported that BDNF is also aberrantly expressed in human breast cancer and that a raised level of BDNF is associated with poor clinical outcome and reduced survival. The present study aimed to investigate the biological role of BDNF in human breast cancer. Materials and methods: A panel of human breast cancer cells were used in the present study. The expression profile of BDNF was evaluated using RT-PCR. We constructed a set of anti-BDNF transgenes which were used to transfect breast cancer cells in order to generate BDNF knockdown cells (MCFΔBDNF). The impact of BDNF knockdown on growth and cellular migration were evaluated using standard growth assays and ECIS (electronic cell impedance sensing) technology.

Results: BDNF gene transcripts were successfully detected in the breast cancer cell lines, MCF-7, MDA MB-231 and ZR 75-1. MCF-7 wild type cells were subject to transfection of anti-BDNF transgenes, followed by the establishment of BDNF knockdown sub-lines and empty vector control cells (MCFpef). Loss of BDNF in breast cancer cells resulted in reduction of cell growth rate (growth rate in MCFΔBDNF by day 3 1.60+/−0.11, compared with 2.06+/−0.04 in MCFpef, p=0.006). Using electric cell-substrate impedance sensing, it was found that loss of BDNF in breast cancer cells resulted in a significant increase in the rate of cellular attachment and migration (migration rate over 14 h in ohms: MCFΔBDNF 6310.125+/−595.183 compared with MCFpef 5115.5 +/−422.394, p=0.0003).

Conclusion: When BDNF was stably knocked down in MCF-7 cell lines, the growth and proliferation were decreased. The ECIS results also showed that cell migration was decreased in MCF-7 cells stably transfected with ribozymes for BDNF compared with the vector control. It is concluded that BDNF, a neurotrophic growth factor aberrantly expressed in cancers such as breast cancer, has a profound impact on the cellular behaviour of breast cancer cells and that loss of BDNF is associated with a reduction of the aggressiveness of breast cancer. BDNF is therefore a potential therapeutic target in breast cancer and its effect in human breast cancer requires further investigation.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-01-21.

Bee-hawking by the wasp, Vespa velutina, on the honeybees Apis cerana and A. mellifera

The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.

[Effect of acryl thiourea on liver pathologic changes in mice infected with Schistosoma japonicum]

OBJECTIVE

To observe the effect of acryl thiourea, an inhibitor of phenol oxidase, on pathological changes in the liver of mice infected with Schistosoma japonicum.

METHODS

From day 22 to day 42 postinfection with cercariae, the mice of the acryl thiourea group were each injected i.p. with acryl thiourea at a dose of 300 mg/kg every other day. The mice were killed on the 42nd day postinfection to observe the pathological changes in the liver.

RESULTS

Compared to the infected control group, the liver tissue of the acryl thiourea group showed scattered foci of inflammatory cell infiltration, the mean diameter and area of the foci were significantly reduced (P < 0.01), and there were no eggs in the center of the foci except for some granules.

CONCLUSION

After i.p. injections of acryl thiourea, no typical egg granuloma was found in the liver of infected mice. This was possibly due to the inhibition of schistosome phenol oxidase activity and so the female adult schistosomes could not produce normal eggs.

Correlation with redox potentials and inhibitory effects on Epstein-Barr virus activation of azaanthraquinones

The redox potentials have been determined for nine azaanthraquinones in phosphate buffer at pH 7.2 by means of cyclic voltammetry. A definite correlation has been found between the redox potentials and the inhibitory effects of the azaanthraquinones on Epstein-Barr virus early antigen (EBV-EA) activation. It has further been shown that the correlation can be made better by introducing an electronic property, i.e., the atomic charge at O11 as an additional parameter.

Role of human liver P450s and cytochrome b5 in the reductive metabolism of 3'-azido-3'-deoxythymidine (AZT) to 3'-amino-3'-deoxythymidine

Our laboratory has shown that human liver microsomes metabolize the anti-HIV drug 3'-azido-3'-deoxythymidine (AZT) via a P450-type reductive reaction to a toxic metabolite 3'-amino-3'-deoxythymidine (AMT). In the present study, we examined the role of specific human P450s and other microsomal enzymes in AZT reduction. Under anaerobic conditions in the presence of NADPH, human liver microsomes converted AZT to AMT with kinetics indicative of two enzymatic components, one with a low Km (58-74 microM) and Vmax (107-142 pmol AMT formed/min/mg protein) and the other with a high Km (4.33-5.88 mM) and Vmax (1804-2607 pmol AMT formed/min/mg). Involvement of a specific P450 enzyme in AZT reduction was not detected by using human P450 substrates and inhibitors. Antibodies to human CYP2E1, CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2A6 were also without effect on this reaction. NADH was as effective as NADPH in promoting microsomal AZT reduction, raising the possibility of cytochrome b5 (b5) involvement. Indeed, AZT reduction among six human liver samples correlated strongly with microsomal b5 content (r2 = 0.96) as well as with aggregate P450 content (r2 = 0.97). Upon reconstitution, human liver b5 plus NADH:b5 reductase and CYP2C9 plus NADPH:P450 reductase were both effective catalysts of AZT reduction, which was also supported when CYP2A6 or CYP2E1 was substituted for CYP2C9. Kinetic analysis revealed an AZT Km of 54 microM and Vmax of 301 pmol/min for b5 plus NADH:b5 reductase and an AZT Km of 103 microM and Vmax of 397 pmol/min for CYP2C9 plus NADPH:P450 reductase. Our results indicate that AZT reduction to AMT by human liver microsomes involves both b5 and P450 enzymes plus their corresponding reductases. The capacity of these proteins and b5 to reduce AZT may be a function of their heme prothestic groups.

p38-2, a novel mitogen-activated protein kinase with distinct properties

Mitogen-activated protein (MAP) kinases are involved in many cellular processes. Here we describe the cloning and characterization of a new MAP kinase, p38-2. p38-2 belongs to the p38 subfamily of MAP kinases and shares with it the TGY phosphorylation motif. The complete p38-2 cDNA was isolated by polymerase chain reaction. It encodes a 364-amino acid protein with 73% identity to p38. Two shorter isoforms missing the phosphorylation motif were identified. Analysis of various tissues demonstrated that p38-2 is differently expressed from p38. Highest expression levels were found in heart and skeletal muscle. Like p38, p38-2 is activated by stress-inducing signals and proinflammatory cytokines. The preferred upstream kinase is MEK6. Although p38-2 and p38 phosphorylate the same substrates, the site specificity of phosphorylation can differ as shown by two-dimensional phosphopeptide analysis of Sap-1a. Additionally, kinetic studies showed that p38-2 appears to be about 180 times more active than p38 on certain substrates such as ATF2. Both kinases are inhibited by a class of pyridinyl imidazoles. p38-2 phosphorylation of ATF2 and Sap-1a but not Elk1 results in increased transcriptional activity of these factors. A sequential kinetic mechanism of p38-2 is suggested by steady state kinetic analysis. In conclusion, p38-2 may be an important component of the stress response required for the homeostasis of a cell.

Glycerol increases content and activity of human cytochrome P-4502E1 in a transduced HepG2 cell line by protein stabilization

Glycerol is widely used to stabilize cytochrome P-450 and prevent its transformation to cytochrome P-420. The effect of glycerol on the content and activity of human cytochrome P-4502E1 (CYP2E1) in a HepG2 cell line that stably and constitutively expresses this P-450 was evaluated by immunoassays and oxidation of p-nitrophenol. Addition of 100 to 200 mM glycerol to the culture medium resulted in a 2 1/2- to 3-fold increase in the content and activity of CYP2E1 in microsomes isolated from the cells. Increases could be observed within 4 to 8 hr after addition of glycerol to the culture medium. Glycerol had no effect on the content of cytochrome b5 or activities of NADPH-cytochrome P-450 reductase or NADH-cytochrome b5 reductase. Upon the addition of cycloheximide to stop protein synthesis, CYP2E1 content and activity decreased with apparent half-lives of 6 and 4 hr, respectively. Glycerol prevented or decreased this loss of CYP2E1 content and activity. Labeling CYP2E1 with [35S]methionine, followed by pulse-chase experiments with cold methionine and immunoprecipitation of CYP2E1 indicated a half-life for CYP2E1 of approximately 3 hr. Glycerol increased the half-life to approximately 11 hr. Stabilization of CYP2E1 protein by glycerol was not additive or synergistic with the increase of CYP2E1 by ethanol or 4-methylpyrazole, suggesting that all three agents elevate CYP2E1 by a similar type of mechanism in this model. These results indicate that glycerol can interact with human CYP2E1 to stabilize it against proteolytic degradation, increasing the half-life of the enzyme and thereby elevating the content and activity of CYP2E1.

Characterization of cytochrome P4502E1 turnover in transfected HepG2 cells expressing human CYP2E1

The aim of the present study was to characterize human CYP2E1 turnover and examine the possible proteolytic pathways responsible for the rapid degradation of CYP2E1 in a transfected HepG2 cell line expressing human CYP2E1. Two methods were used to study the CYP2E1 turnover; after addition of cycloheximide, the half-life of the CYP2E1 in the intact cells was about 6 h as detected by PNP catalytic activity assay and immunoblot analysis of apoprotein content. CYP2E1 substrates or ligands such as 4-methylpyrazole, ethanol, glycerol, and dimethyl sulfoxide protected CYP2E1 against this rapid degradation, whereas CCl4 accelerated this process. The second procedure involved pulse-chase experiments after labeling CYP2E1 with [35S]methionine and immunoprecipitation with anti-human CYP2E1 IgG. The half-life of CYP2E1 was about 2.5 h, and the various substrates or ligands modified the turnover process within intact cells as described for the cycloheximide experiments. More than 20 different reagents including antioxidants, physiological metabolites, lysosomal inhibitors, and protease inhibitors were screened for possible effects on CYP2E1 proteolytic degradation. Dibutyryl cAMP had no effect on CYP2E1 activity or turnover. Among those reagents tested so far, the serine protease inhibitor 1-chloro-3-tosylamido-7-amino-2-heptanone hydrochloride exhibited some protection against CYP2E1 degradation. To demonstrate whether the proteasome complex is involved in this process, Czb-Ile-Glu(OtBu)-Ala-leucinal (PSI) as a cell penetrating aldehydic proteasome inhibitor and Czb-Leu-norleucinal (calpeptin inhibitor) as an aldehydic nonproteosomal protease inhibitor were used to examine their effect on both the normal and the CCl4-stimulated CYP2E1 proteolytic degradation pathways. Treatment with PSI at concentrations ranging from 5 to 80 microM resulted in a dose-dependent protection against the loss of both the normal CYP2E1 and the CCl4-modified CYP2E1. The maximum protection by PSI at a concentration of 80 microM after a 12-h chase period was about 60% in cells treated with 2 mM CCl4 or 75% in cells without CCl4 treatment. Calpeptin inhibitor afforded little or no protection against CYP2E1 degradation in the absence or presence of CCl4. PSI did not inhibit CYP2E1 catalytic activity, suggesting that it was not a ligand for CYP2E1. These results indicate that human CYP2E1 has a short half-life span and that substrates can significantly modify its turnover rate in intact HepG2 cells. The proteasome proteolytic pathway may be involved in the degradation process of both the normal and the CCl4-modified human CYP2E1 in this model.

Role of the proteasome complex in degradation of human CYP2E1 in transfected HepG2 cells

The aim of the present study was to characterize human CYP2E1 turnover and examine the possible role of the proteasome proteolytic pathway in the rapid degradation of CYP2E1 in a transfected HepG2 cell line expressing human CYP2E1. Microsomes isolated from MVh2E1-9 cells catalyzed a slow degradation of the expressed CYP2E1, which was prevented by the addition of 4-methylpyrazole, a ligand which stabilizes CYP2E1. The addition of the cytosolic fraction of the HepG2 cells to the microsomes produced rapid degradation of CYP2E1. This rapid degradation required MgATP and was completely prevented by 4-methylpyrazole. Pulse-chase experiments after labeling CYP2E1 with [35S]-methionine and immunoprecipitation with anti-human CYP2E1 IgG indicated a biphasic turnover of CYP2E1 with half-lives of 2.5 and 6 hours. The addition of Czb-Ile-Glu(OtBu)-Ala-Leucinal(PSI) as a cell penetrating proteasome inhibitor, at concentrations ranging from 5 to 80 microM resulted in protection against the degradation of CYP2E1. PSI also increased the steady state accumulation of CYP2E1, consistent with its inhibition of CYP2E1 turnover. These results suggest that the proteasome complex plays a major role in the degradation of human CYP2E1 in the transfected HepG2 cells.

Interaction of ferric complexes with NADH-cytochrome b5 reductase and cytochrome b5: lipid peroxidation, H2O2 generation, and ferric reduction

NADH is reactive in interacting with iron and liver microsomes to catalyze the formation of reactive oxygen species. NADH-dependent microsomal electron transfer involves the enzymes NADH-cytochrome b5 reductase and cytochrome b5. Experiments were carried out to evaluate the ability of reconstituted systems containing purified reductase in the absence or presence of b5 to reduce several ferric complexes, to generate H2O2, and to catalyze lipid peroxidation. The reductase directly reduced ferric-EDTA; addition of b5 inhibited this reduction probably due to competition for the reductase. Cytochrome b5 was required for reduction of low (5 microM) and high (50 microM) concentrations of ferric-histidine and ferric-ammonium sulfate and low concentrations of ferric-ATP. The reductase could interact directly with high (50 microM) concentrations of ferric-ATP. Peroxidation of phospholipids extracted from liver microsomes by the reductase required b5. Molar ratios of b5 to reductase approximating those found in liver microsomes (e.g., 10) were effective in catalyzing lipid peroxidation and ferric reduction. The role of b5 in catalyzing lipid peroxidation appears to involve reduction of the ferric catalyst to help form an initiation complex and degradation of lipid hydroperoxides by the hemeprotein to catalyze propagation of the peroxidation cycle. In contrast to results with microsomes, lipid peroxidation by the complete reconstituted system was sensitive to super-oxide dismutase; this sensitivity was decreased if the reconstituted system was dialyzed overnight to form vesicular preparations, indicating that accessibility of enzymes to sites of peroxidation was important. High rates of H2O2 formation were observed in the presence of ferric-EDTA plus reductase; rates of H2O2 formation with the other ferric complexes were low even in the presence of b5. These results indicate that the ability of NADH reductase and cytochrome b5 to interact with various ferric complexes depends on the nature of the chelating agent used to complex the iron and on the concentration of the iron.

Cloning and characterization of MEK6, a novel member of the mitogen-activated protein kinase kinase cascade

Mitogen-activated protein kinases are members of a conserved cascade of kinases involved in many signal transduction pathways. They stimulate phosphorylation of transcription factors in response to extracellular signals such as growth factors, cytokines, ultraviolet light, and stress-inducing agents. A novel mitogen-activated protein kinase kinase, MEK6, was cloned and characterized. The complete MEK6 cDNA was isolated by polymerase chain reaction. It encodes a 334-amino acid protein with 82% identity to MKK3. MEK6 is highly expressed in skeletal muscle like many other members of this family, but in contrast to MKK3 its expression in leukocytes is very low. MEK6 is a member of the p38 kinase cascade and efficiently phosphorylates p38 but not c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) family members in direct kinase assays. Coupled kinase assays demonstrated that MEK6 induces phosphorylation of ATF2 by p38 but does not phosphorylate ATF2 directly. MEK6 is strongly activated by UV, anisomycin, and osmotic shock but not by phorbol esters, nerve growth factor, and epidermal growth factor. This separates MEK6 from the ERK subgroup of protein kinases. MEK6 is only a poor substrate for MEKK, a mitogen-activated protein kinase kinase kinase that efficiently phosphorylates the related family member JNKK.

1-Hydroxyethyl radical formation during NADPH- and NADH-dependent oxidation of ethanol by human liver microsomes

Ethanol can be oxidized to the 1-hydroxyethyl radical (HER) by rat and deer mice liver microsomal systems. Experiments were carried out to evaluate the ability of human liver microsomes to catalyze this reaction, compare the effectiveness of NADH with that of NADPH, and assess the possible role of cytochrome b5 in HER formation. HER was detected as the alpha-(4-pyridly-1 -oxide)-N-t-butylnitrone/HER adduct. Human liver microsomes catalyzed HER formation with either NADPH or NADH as cofactor; rates with NADH were approximately 50% those found with NADPH. Chelex-100 treatment of the reaction mixture produced marked inhibition of HER formation, suggesting that a transition metal, such as iron, was required to catalyze the reaction. The addition of ferric chloride restore HER formation. Catalase (2600 units/ml) and superoxide dismutases (500 units/ml) nearly completely inhibited the reaction with either NADPH or NADH. The NADH-dependent rates of superoxide production, detected as 5,5-dimethyl-1-pyrroline-N-oxide-O2H, were approximately 50% the NADPH-dependent rates, which is consistent with the rates of HER formation. Anti-cytochrome b5 IgG decreased NADPH- and NADH-dependent HER formation, and this was associated with inhibition of superoxide formation with both reductants. These results indicate that human liver microsomes can catalyze the oxidation of ethanol of HER with either NADPH or NADH as reductant. The effectiveness of NADH may be significant in view of the increased NADH/NAD+ redox ratio in the liver as a consequence of ethanol oxidation by alcohol dehydrogenase. HER formation by human liver microsomes seems to be catalyzed by an oxidant derived from the interaction of iron with superoxide or H2O2, and a close association exists between HER formation and superoxide production. Cytochrome b5 seems to play a role in HER formation, most likely due to its effect on superoxide production.

Role of cytochrome b5 in NADH-dependent microsomal reduction of ferric complexes, lipid peroxidation, and hydrogen peroxide generation

The NADH-dependent microsomal electron transfer system consists of NADH-cytochrome b5 reductase and cytochrome b5, which donates reducing equivalents to fatty acyl desaturase, cytochrome P450, and other reactions. A study was carried out to investigate the interaction of NADH with several ferric complexes and to evaluate the role of cytochrome b5 in these interactions. NADH-dependent microsomal lipid peroxidation was stimulated by ferric-ATP, ferric-histidine, and ferric-ammonium sulfate, but not by ferric-EDTA. Anti-cytochrome b5 IgG produced a concentration-dependent inhibition of lipid peroxidation catalyzed by all three ferric complexes. Addition of purified cytochrome b5 to the microsomes increased the rate of lipid peroxidation with all three ferric complexes. Lipid peroxidation in control and the cytochrome b5-fortified microsomes was not sensitive to superoxide dismutase, catalase, or DMSO and was completely inhibited by trolox and propylgallate. Ferric-EDTA stimulated NADH-dependent microsomal production of H2O2 and NADH consumption. Anti-cytochrome b5 IgG had only a small inhibitory effect on this stimulation by ferric-EDTA. NADH supported microsomal reduction of ferric complexes in the order ferric-ATP > ferric-histidine approximately ferric-ammonium sulfate > ferric-EDTA. Anti-cytochrome b5 IgG inhibited, whereas added cytochrome b5 stimulated, the reduction of ferric-ATP, ferric-histidine, and ferric-ammonium sulfate, whereas reduction of ferric-EDTA was not affected by these additions. Ferric-ATP, at high concentrations, was more effective than ferric-histidine or ferric-ammonium sulfate in stimulating lipid peroxidation and in becoming reduced by NADH-dependent microsomal electron transport; anti-cytochrome b5 IgG was less inhibitory and added b5 was less stimulatory at 50 microM ferric-ATP compared to 5 microM ferric-ATP or 50 microM ferric-histidine or 50 microM ferric-ammonium sulfate. It is concluded that cytochrome b5 is required for reduction of low and high concentrations of ferric-histidine and ferric-ammonium sulfate and low concentrations of ferric-ATP and for the lipid peroxidation catalyzed by these ferric complexes. The reductase, not cytochrome b5, is involved in interaction with ferric-EDTA. Higher concentrations of ferric-ATP can also interact with the reductase, as well as with cytochrome b5.

Repression of the interleukin-6 promoter by estrogen receptor is mediated by NF-kappa B and C/EBP beta

Bone metabolism is regulated by a balance between bone resorption caused by osteoclasts and bone formation caused by osteoblasts. This balance is disturbed in postmenopausal women as a result of lower serum estrogen levels. Estrogen, which is used in hormone replacement therapy to prevent postmenopausal osteoporosis, downregulates expression of the interleukin 6 (IL-6) gene in osteoblasts and bone marrow stromal cells. IL-6 is directly involved in bone resorption by activating immature osteoclasts. We show here that NF-kappa B and C/EBP beta are important regulators of IL-6 gene expression in human osteoblasts. Importantly, the IL-6 promoter is inhibited by estrogen in the absence of a functional estrogen receptor (ER) binding site. This inhibition is mediated by the transcription factors NF-kappa B and C/EBP beta. Evidence is presented for a direct interaction between these two factors and ER. We characterized the protein sequence requirements for this association in vitro and in vivo. The physical and functional interaction depends in part on the DNA binding domain and region D of ER and on the Rel homology domain of NF-kappa B and the bZIP region of C/EBP beta. The cross-coupling between ER, NF-kappa B, and C/EBP beta also results in reduced activity of promoters with ER binding sites. We further show that the mechanism of IL-6 gene repression by estrogen is clearly different from that of activation of promoters with ER binding sites. Therefore, drugs that separate the transactivation and transrepression functions of ER will be very helpful for treatment of osteoporosis without causing undesirable side effects.

Fractionation of liver microsomes with polyethylene glycol and purification of NADH-cytochrome b5 oxidoreductase and cytochrome b5

A simplified, rapid procedure for the purification of NADH-cytochrome b5 oxidoreductase and cytochrome b5 from either rat or rabbit liver is described. Microsomes were prepared by fractionation with polyethylene glycol and solubilized with Triton X-100. Cytochrome b5 was purified by a two-column procedure, anion exchange chromatography using DEAE-cellulose, and hydrophobic chromatography on phenyl-Sepharose. The final preparation of cytochrome b5 was purified more than a 120-fold from rat or rabbit liver microsomes, with specific content of about 50 nmol per mg protein, and overall yield of 22 to 32%. Only a single band with mol wt of 18,600 was found on sodium dodecyl sulfate (SDS)-gels or on Western blots using a polyclonal antibody raised against the purified b5. NADH-cytochrome b5 oxidoreductase was purified by a three-column procedure, DEAE-cellulose, hydroxylapatite, and ADP-agarose. The final product was purified more than 400-fold from rat or rabbit liver microsomes with a yield of about 25% and final specific activity of about 1600 mumol ferricyanide reduced per minute per milligram of protein. A single band with mol wt of 33, 100 was found on SDS-gels. The reductase catalyzed reduction of ferricyanide, dichlorophenol-indophenol, and cytochrome b5. Cytochrome c was reduced in the presence of reductase plus cytochrome b5, and this was inhibited by the anti-b5 IgG. The reductase catalyzed a rapid rate of reduction of ferric-ATP, which was slightly elevated by cytochrome b5. Ferric-histidine and ferric-ammonium sulfate were slowly reduced by reductase; addition of cytochrome b5 markedly stimulated reduction of these ferric complexes but inhibited reduction of ferric-EDTA.(ABSTRACT TRUNCATED AT 250 WORDS)

[Studies on culturing seeds of Tripterygium hypoglaucum (Level.) Hutch. in vitro]

This paper for the first time reports the embryo culturing in vitro of Tripterygium hypoglaucum. Tests were conducted of every condition for the normal germination and growth of the excised embryo. The result shows that the germination ratio reaches the highest on the white basic medium when the intensity of light is 400Lx, sucrose concentration is 3% and whole nitrogen content is 230 mg/L. Intact plantlets are obtained from the aseptic shoots. A method using aseptic shoots to accelerate the propagation of plantlets is found primarily.