Neuroprotective effect of cerebroprotein hydrolysate-Ⅰ on ischemia-reperfusion injury in rats / 国际脑血管病杂志

Objective:To investigate the neuroprotective effect of cerebroprotein hydrolysate (CH) -Ⅰ on cerebral ischemia-reperfusion injury in rats and its mechanism.Methods:Eighty adult healthy male SD rats were randomly divided into sham operation group, model group, CH-Ⅰ intervention group and cerebrolysin (CBL) positive control group. The model of ischemia-reperfusion injury was induced by temporarily occluding the left middle cerebral artery with suture-occluded method. The CH-Ⅰ and CBL groups intraperitoneally injected with CH-Ⅰ and CBL at 0, 3, 6 and 12 h after reperfusion at the dose of 20 mg/kg. The sham operation group and the model group were injected with the same volume of normal saline. At 24 h after reperfusion, the behavior changes of the rats were detected by the modified neurological severity score (mNSS). The volume of cerebral infarction was detected by TTC staining. The morphology and structure of neurons in ischemic cortex were observed by Nissl staining. The apoptosis of neurons in ischemic cortex was detected by TUNEL staining. The expression changes of phosphorylated extracellular signal-regulated kinase (pERK) 1/2, phosphorylated mitogen-activated protein kinase/extracellular signal-regulated kinase (pMEK) 1/2, phosphorylated cAMP response element binding protein (pCREB) and brain-derived neurotrophic factor (BDNF) in the ischemic cortex were detected by Western blot.Results:At 24 h after reperfusion, the mNSS score and cerebral infarct volume in the model group were significantly higher and larger than those in the sham group (all P<0.001). The mNSS scores and cerebral infarct volumes in the CH-Ⅰ and CBL groups were significantly reduced compared with those in the model group (all P<0.05), but there was no significant difference between the CH-Ⅰ group and the CBL group. Nissl and TUNEL staining showed that the degenerative cell index and apoptotic cell index in the CH-Ⅰ group were significantly lower than those in the model group (all P<0.01), but there were no significant difference between the CH-Ⅰ group and the CBL group. Western blot analysis showed that compared with the sham operation group, the pMEK1/2, pERK1/2 and pCREB expressions in ischemic cortex were significantly enhanced and the BDNF expression was significantly attenuated in the model group ( P<0.05). Compared with the model group, pMEK1/2, pERK1/2, and pCREB expressions in the CH-Ⅰ group were significantly decreased (all P<0.05), and the BDNF expression was significantly increased ( P<0.05). Conclution:CH-Ⅰ can reduce cerebral infarct volume and improve neurological function, and its mechanism may be associated with the inhibition of the MEK-ERK-CREB pathway as well as the enhancement of BDNF expression.

Chiropractic plus plum-blossom needling combined with flexibility training on attention deficit in mentally-retarded adolescents / 中国针灸

OBJECTIVE@#To observe the clinical efficacy of chiropractic plus plum-blossom needling combined with flexibility training for attention deficit in mentally-retarded adolescents.@*METHODS@#Thirty adolescents with mild mental retardation were randomly divided into a medical rehabilitation plus flexibility training group (10 cases, 2 cases dropped off), a flexibility training group (10 cases, 1 case dropped off) and a control group (10 cases). The patients in the flexibility training group received flexibility training, once every other day, 3 times a week for 12 weeks. The patients in the medical rehabilitation plus flexibility training group received chiropractic and plum-blossom needling at Baihui (GV 20) and Sishencong (EX-HN 1) on the basis of the treatment in the flexibility training group, once every other day, 3 times a week for 12 weeks. The patients in the control group did not receive any targeted physical training and medical rehabilitation. Tobii Pro Spectrum eye movement instrument was used to test the attention concentration (T), attention span (M), attention transfer (γ%) and attention distribution (η).@*RESULTS@#Compared before treatment, T and M in the medical rehabilitation plus flexibility training group and the flexibility training group were increased after treatment (P<0.01, P<0.05), and γ% in the medical rehabilitation plus flexibility training group was increased after treatment (P<0.05). The increasing range of T, M and γ% in the medical rehabilitation plus flexibility training group and the flexibility training group was greater than that in the control group (P<0.01), and the increasing range of T and γ% in the medical rehabilitation plus flexibility training group was greater than that in the flexibility training group (P<0.05).@*CONCLUSION@#The chiropractic plus plum blossom needling combined with flexibility training can improve the attention deficit in mentally-retarded adolescents.

Multicentric reticulohistiocytosis: A case report / 北京大学学报(医学版)

A 65-year-old woman developed erythema, papules and nodules over the body. Some nodules of her auricles and hands like string beads. Besides, she suffered from symmetrical swelling and pain of multiple joints, morning stiffness with deformity of joints; She had elevated erythrocyte sedimentation rate and C reactive protein levels; Her rheumatoid factor and antinuclear antibody were positive; Joints destruction was found with X-ray imaging; Skin pathology showed Dermal infiltrate of abundant histiocytes, part of them with a ground-glass appearance; A CD68 immunohistochemical stain was positive and the cells were negative for S100, CD1a. These findings were diagnostic evidences of multicentric reticulohistiocytosis (MRH). The patient received high-dose of glucocorticoids combinated with immunosuppressive agents, and achieved a satisfactory effect. MRH was a rare multisystem disease characterized by papulonodular mucocutaneous and destructive arthritis, and its pathogeny was not yet completely understood. The typical lesions of MRH were hard papules or nodules that usually occured on the hands, face and arms. Classic coral bead appearance from periungual cutaneous nodules that were characteristic of MRH. MRH was an inflammatory joint disease, affecting almost all the appendicular joints and characterized by joint multiple, symmetrical, destructive, progressive disability. Joints destruction of the distal interphalangeal joints was a unique feature of MRH. In addition to skin and joints, it could also involve other systems. There were no diagnostic laboratory markers for MRH. Laboratory examinations had often been found to be non-specific. Imageological examination mainly showed bone and joint destruction. Skin biopsy was the best test to diagnose MRH, the typical histopathological findings included an infiltrate with histiocytes and multinucleated giant cells with a ground-glass appearing in eosinophilic cytoplasm, and the immunohistochemical stain was positive for CD68. The diagnosis was typically made based on the clinical presentation, supportive radiographic findings and skin biopsy. MRH was easily possible to mistake for other more common autoimmune conditions, such as rheumatoid arthritis, psoriatic arthritis, osteoarthritis, and dermatomyositis, but the distinctive clinical, radiographic, and histologic features could aid in differentiating these diseases. MRH could mimic other rheumatic diseases, besides, it could also coexist with cancer or other autoimmune disorders. There was no standardized treatment for MRH. However, Nonsteroidal anti-inflammatory drugs, glucocorticoid, Immunosuppressant, biologic medications, and bisphosphonates had been used with varying degrees of curative effect. Treatment with glucocorticoid combined with immunosuppressants were effective for rash and arthritis, early use of them should be strongly considered, and refractory cases could be treated with biological agents. By reporting a MRH case and reviewing literature, this paper aims to help the clinicians improve the understanding of this rare disease, and suggests that when one diagnosis cannot explain the whole picture of the disease, and further evidence should be sought to confirm the diagnosis.

FOXA2 improves liver function and blood lipid levels in mice with intrahepatic cholestasis and hyperlipidemia / 中国药理学通报

Aim To study the regulatory effect of FOXA2 on liver function and blood lipid levels in mice with intrahepatic cholestasis and hyperlipidemia. Methods The model was constructed by feeding high cholesterol/cholic acid (CAD), and the FOXA2 plasmid was injected into the liver of mice by tail vein hypertension, so that the hepatocytes overexpressed F0XA2. The automatic blood biochemical analyzer was uses to detect the blood biochemical indicators of the serum, the colorimetric method to detect the cholesterol level in liver, and ELISA method to detect the liver bile acid level. Western blot was used to determine the expression of liver FOXA2, and RT-PCR to assess the mRNA expression of genes related to bile acid metabolism. H&E and oil red staining were employed to observe liver pathology. Results With the extension feeding time of the CAD, the weight of the mice continued to decrease (P < 0.01), the gallbladder increased significantly (P < 0.01), and the level of transaminase increased, and serum cholesterol and low-density lipoprotein cholesterol (P < 0.01) increased significantly. Liver tissue structure was damaged, liver cholesterol was elevated (P <0.01), bile acid level increased (P < 0.01), and lipid accumulation was serious. Overexpression of FOXA2 could significantly improve liver function and dyslipidemia in CAD-fed mice by regulating liver bile acid metabolism genes, and reduce liver bile acid levels (P < 0.01) and liver lipid accumulation. Conclusions FOXA2 improves liver function and blood lipid levels in mice with intrahepatic cholestasis and hyperlipidemia.

Application of intravenous sedation in 2 582 cases of oral and maxillofacial surgery / 北京大学学报(医学版)

OBJECTIVE@#To analyze the clinical data of patients undergoing intravenous sedation in oral and maxillofacial surgery, to understand the epidemiological characteristics, to evaluate the efficacy and safety of intravenous sedation for oral surgery, and to summarize our experience.@*METHODS@#We retrospectively reviewed the clinical data of patients undergoing intravenous sedation between January 2010 and December 2018 in the Department of Oral and Maxillofacial Surgery, Peking University School of Stomatology. The gender, age, source, disease types, the values of perioperative vital signs, the use of sedatives and analgesics, duration of surgery and sedation, effect of sedation during the operation and the postoperative anterograde amnesia were analyzed.@*RESULTS@#A total of 2 582 patients experienced oral surgery by intravenous sedation. The peak age was 3.5 to 10 years and between 21 to 40 years. Supernumerary teeth (38%, 981/2 582) and impacted third molars (30%, 775/2 582) were the major disease types, and other types of disease accounted for 32 percent (826/2 582). The values of heart rate(HR), mean arterial pressure(MAP), respiration rate(RR) and bispectral index(BIS) showed statistically significant differences at the time of before sedation, local anesthesia injection, surgical incision, 10 min after operation and the end of operation. In the study, 69%(1 781/2 582) cases received midazolam alone, 7%(181/2 582) cases received propofol alone, and 24% (620/2 582) cases received midazolam and propofol combined for intravenous sedation. Fentanyl (33%, 852/2 582)was the most common intravenous analgesic we used, followed by flurbiprofen axetil (23%, 594/2 582) and ketorolac tromethamine (6%, 157/2 582). Besides, 35% (907/2 582) patients didn't use any intravenous analgesic during the surgery. The average operation time was (31.2±20.8) min, and the average sedation time was (38.4±19.2) min. During the surgery procedure, most of the patients scored on a scale of 2 to 4 according to the Ramsay sedation score (RSS). The postoperative anterograde amnesia rates of local anesthesia injection, surgical incision and dental drill during surgery were 94% (2 431/2 582), 92% (2 375/2 582) and 75% (1 452/1 936).@*CONCLUSION@#Intravenous sedation on the oral and maxillofacial surgery is effective and safe, can make the patients more comfortable, and should be further promoted and applied.

Discoidin Domain Receptor 1 (DDR1) tyrosine kinase is upregulated in PKD kidneys but does not play a role in the pathogenesis of polycystic kidney disease.

Tolvaptan is the only drug approved to slow cyst growth and preserve kidney function in patients with autosomal dominant polycystic kidney disease (ADPKD). However, its limited efficacy combined with significant side effects underscores the need to identify new and safe therapeutic drug targets to slow progression to end stage kidney disease. We identified Discoidin Domain Receptor 1 (DDR1) as receptor tyrosine kinase upregulated in vivo in 3 mouse models of ADPKD using a novel mass spectrometry approach to identify kinases upregulated in ADPKD. Previous studies demonstrating critical roles for DDR1 to cancer progression, its potential role in the pathogenesis of a variety of other kidney disease, along with the possibility that DDR1 could provide new insight into how extracellular matrix impacts cyst growth led us to study the role of DDR1 in ADPKD pathogenesis. However, genetic deletion of DDR1 using CRISPR/Cas9 failed to slow cyst growth or preserve kidney function in both a rapid and slow mouse model of ADPKD demonstrating that DDR1 does not play a role in PKD pathogenesis and is thus a not viable drug target. In spite of the negative results, our studies will be of interest to the nephrology community as it will prevent others from potentially conducting similar experiments on DDR1 and reinforces the potential of performing unbiased screens coupled with in vivo gene editing using CRISPR/Cas9 to rapidly identify and confirm new potential drug targets for ADPKD.

Protective effects of tetramethylpyrazine analogue Z-11 on cerebral ischemia reperfusion injury.

The aim of our study was to investigate the effects of a new synthetic compound (E) -1- (E) -1- (2- hydroxy -5- chlorophenyl) -3- (3, 5, 6- three methyl pyrazine -2- based) -2- propylene -1 ketone, Z-11, a tetramethylpyrazine analogue, on cerebral ischemia reperfusion injury and the underlying mechanism. 240-260 g adult male Wistar rats were subjected to middle cerebral artery occlusion for 2 h, followed by 22 h of reperfusion. Z-11 (1.7, 3.4 and 6.8 mg/kg, i.p.), Edaravone (3 mg/kg, i.p.) and DMSO (1‰, i.p.) was administered at 2 h after the onset of ischemia. The rats' neurological score, infarct volume, and body weight change were tested, and some oxidative stress markers such as superoxide dismutase (SOD) activity, glutathione (GSH) and malondialdehyde (MDA) contents were evaluated after 22 h of reperfusion. Results showed that neurologic deficit, infarct volume and body weight change were ameliorated after cerebral ischemia reperfusion, and that Z-11 exhibits an excellent effect at a dosage of 6.8 mg/kg. This dose also reduced the content of MDA, and upregulated SOD activity and GSH content. Similarly, 6.8 mg/kg Z-11 treatment inhibited the reactive oxygen species content and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, with the protein levels of Ras-related C3 botulinum toxin substrate1(Rac-1) and mitogenic oxidase (Nox2) downregulated even further. Moreover, the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream anti-oxidant protein heme oxygenase-1 (HO-1) were upregulated. This indicates that Z-11 could play a protective role in cerebral ischemia-reperfusion injury, and that the protective effect of Z-11 may be related to improvements in the antioxidant capacity of brain tissue. The mechanisms are associated with enhancing oxidant defence systems via the activation of Nrf2/HO-1 and Rac-1/NADPH oxidase pathways.

Glutamine metabolism via glutaminase 1 in autosomal-dominant polycystic kidney disease.

Background: Metabolism of glutamine by glutaminase 1 (GLS1) plays a key role in tumor cell proliferation via the generation of ATP and intermediates required for macromolecular synthesis. We hypothesized that glutamine metabolism also plays a role in proliferation of autosomal-dominant polycystic kidney disease (ADPKD) cells and that inhibiting GLS1 could slow cyst growth in animal models of ADPKD. Methods: Primary normal human kidney and ADPKD human cyst-lining epithelial cells were cultured in the presence or absence of two pharmacologic inhibitors of GLS1, bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide 3 (BPTES) and CB-839, and the effect on proliferation, cyst growth in collagen and activation of downstream signaling pathways were assessed. We then determined if inhibiting GLS1 in vivo with CB-839 in the Aqp2-Cre; Pkd1fl/fl and Pkhd1-Cre; Pkd1fl/fl mouse models of ADPKD slowed cyst growth. Results: We found that an isoform of GLS1 (GLS1-GAC) is upregulated in cyst-lining epithelia in human ADPKD kidneys and in mouse models of ADPKD. Both BPTES and CB-839 blocked forskolin-induced cyst formation in vitro. Inhibiting GLS1 in vivo with CB-839 led to variable outcomes in two mouse models of ADPKD. CB-839 slowed cyst growth in Aqp2-Cre; Pkd1fl/fl mice, but not in Pkhd1-Cre; Pkd1fl/fl mice. While CB-839 inhibited mammalian target of rapamycin (mTOR) and MEK activation in Aqp2-Cre; Pkd1fl/fl, it did not in Pkhd1-Cre; Pkd1fl/fl mice. Conclusion: These findings provide support that alteration in glutamine metabolism may play a role in cyst growth. However, testing in other models of PKD and identification of the compensatory metabolic changes that bypass GLS1 inhibition will be critical to validate GLS1 as a drug target either alone or when combined with inhibitors of other metabolic pathways.

Regulation of KATP Channel Trafficking in Pancreatic ß-Cells by Protein Histidine Phosphorylation.

Protein histidine phosphatase 1 (PHPT-1) is an evolutionarily conserved 14-kDa protein that dephosphorylates phosphohistidine. PHPT-1-/- mice were generated to gain insight into the role of PHPT-1 and histidine phosphorylation/dephosphorylation in mammalian biology. PHPT-1-/- mice exhibited neonatal hyperinsulinemic hypoglycemia due to impaired trafficking of KATP channels to the plasma membrane in pancreatic ß-cells in response to low glucose and leptin and resembled patients with congenital hyperinsulinism (CHI). The defect in KATP channel trafficking in PHPT-1-/- ß-cells was due to the failure of PHPT-1 to directly activate transient receptor potential channel 4 (TRPC4), resulting in decreased Ca2+ influx and impaired downstream activation of AMPK. Thus, these studies demonstrate a critical role for PHPT-1 in normal pancreatic ß-cell function and raise the possibility that mutations in PHPT-1 and/or TRPC4 may account for yet to be defined cases of CHI.

Astragalus polysaccharide may increase sensitivity of cervical cancer HeLa cells to cisplatin by regulating cell autophagy / 中国中药杂志

This study aimed to investigate the possible sensitivity of Astragalus polysaccharides, in order to improve the chemosensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy, and explore its possible mechanism. In this study, HeLa cells were divided into control group, cisplatin group, Astragalus polysaccharide group, and Astragalus polysaccharide combined with cisplatin group. MTT assay was used to detect the proliferation of cervical cancer HeLa cells. Flow cytometry was used to detect the apoptosis and cycle of HeLa cells in each experimental group. RT-PCR was used to detect the mRNA expression of autophagy-related proteins beclin1, LC3Ⅱ and p62. The expression levels of autophagy-related proteins beclin1, LC3Ⅱ, LC3Ⅰ and p62 were detected by WB method. MTT results showed that compared with the control group, the proliferation of HeLa cells was significantly inhibited in each administration group(<0.05), and the inhibitory effect of the combination group was more significant(<0.01). The apoptotic rate of HeLa cells was significantly increased(<0.05), and the apoptotic rate of the combination group was significantly increased(<0.01) compared with the control group(<0.05).In conclusion, G₀/G₁ phase showed the most significant differences between the two groups. RT-PCR and WB results showed that the gene and protein expressions of beclin1 and LC3Ⅱ were up-regulated, while the gene and protein expressions of p62 were down-regulated compared with the control group. The above-mentioned changes in the combination group were more significant. Through the analysis of the above experimental results, it is speculated that Astragalus polysaccharides may increase the sensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy. Its possible mechanism of action is correlated with the up-regulation of autophagy-related proteins beclin1, the promote the conversion from LC3Ⅰ to LC3Ⅱ, the down-regulation of labeled protein p62, and the enhancement of HeLa cell autophagic activity, thereby increasing the sensitivity of HeLa cells to cisplatin chemotherapy.

Phosphatidlyinositol-3-kinase C2 beta (PI3KC2ß) is a potential new target to treat IgE mediated disease.

Cross linking of the IgE receptor (FcεRI) on mast cells plays a critical role in IgE-dependent allergy including allergic rhinitis, asthma, anaphylaxis, and delayed type hypersensitivity reactions. The Ca2+ activated K+ channel, KCa3.1, plays a critical role in IgE-stimulated Ca2+ entry and degranulation in mast cells by helping to maintain a negative membrane potential, which provides an electrochemical gradient to drive Ca2+ influx. Of the 3 classes of PI3K, the class II PI3Ks are the least studied and little is known about the roles for class II PI3Ks in vivo in the context of the whole organism under normal and pathological conditions. Studying bone marrow derived mast cells (BMMC) isolated from PI3KC2ß-/- mice, we now show that the class II PI3KC2ß is critical for FcεRI stimulated KCa3.1 channel activation and the subsequent activation of mast cells. We found FcεRI-stimulated Ca2+ entry, cytokine production, and degranulation are decreased in BMMC isolated from PI3KC2ß-/- mice. In addition, PI3KC2ß-/- mice are markedly resistant to both passive cutaneous and passive systemic anaphylaxis. These findings identify PI3KC2ß as a new pharmacologic target to treat IgE-mediated disease.

Isolation, purification, characterization and immunostimulatory activity of polysaccharides derived from American ginseng.

In this study, crude American ginseng polysaccharide (AGPS) was extracted with hot water and preliminarily purified by using resin S-8 and Polyamide columns. Then, it was further purified and separated by DEAE-Sepharose CL-6B and Sepharose CL-6B chromatography, respectively. Five main fractions were obtained, named WPS-1, WPS-2, SPS-1, SPS-2 and SPS-3. Their homogeneities and structural characteristics were elucidated based on UV-vis spectroscopy, High Performance Gel Filtration Chromatography (HPGFC), Gas Chromatography (GC), Scanning Electron Microscopy (SEM), Infrared Spectrum (IR), and NMR Spectroscopy methods. Furthermore, the immunostimulatory effects of these fractions upon splenic lymphocyte proliferation, macrophage phagocytosis and nitric oxide (NO) production, were investigated in vitro. The results indicated that their stimulations could be ordered as SPS-3>SPS-1>CPS (crude polysaccharides)>WPS-1>WPS-2>SPS-2. Among them, SPS-3 showed more potent immunomodulatory activity and could be explored as a potential immunopotentiating agent for use in functional food or medicine.

Picroside Ⅱ plays a neuroprotective effect by inhibiting cyto C/caspase-9/caspase-3 signal pathway following ischemia/reperfusion injury in rats / 中国药理学通报

Aim To investigate the neuroprotective effect of picroside Ⅱ(PIC)on cyto C/caspase-9/caspase-3 signal pathway following ischemia/reperfusion(I/R)injury in rats.Methods Atractyloside(Atr)was selected as negative control,cyclosporin A(CsA)was selected as positive control,and PIC was selected as the treatment medicine.The I/R model was made by inserting a monofilament suture into internal carotid artery for 2 h,and then reperfused for 24 h.The cerebral infarction volume was detected by TTC staining,and the expression of cyto C,caspase-9 and caspase-3 were determined by immunohistochemical assay and Western blot.Results In model group,the cerebral infarct volume was obviously large;the expression of cyto C,caspase-9 and caspase-3 was increased significantly more than that in sham group(P<0.05).In PIC group,the cerebral infarct volume was significantly improved;the expression of cyto C,caspase-9 and caspase-3 was significantly decreased than that in model group(P<0.05).In Atr+PIC group,the rat infarction volume was reduced,and the expression of cyto C,caspase-9 and caspase-3 was significantly decreased than that in Atr group(P<0.05).Conclusion The mechanism of PIC inhibiting neuron apoptosis in focal cerebral I/R rats might be through down-regulating the expression of cyto C,caspase-9 and caspase-3.

Expression of proBNP and NT-proBNP in Sudden Death of Coronary Heart Disease / 法医学杂志

Objective To study the expression change of pro-brain natriuretic peptide (proBNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in sudden death of coronary atherosclerotic heart disease,and to explore its application in forensic diagnosis.Methods Myocardial and blood samples were collected from normal control group,sudden death of coronary atherosclerotic heart disease group and single coronary stenosis group (20 cases in each group).The expression of proBNP in myocardial samples were detected by immunohistochemical staining and Western blotting,and that of BNP mRNA were detected by reverse transcription PCR (RT-PCR).The content of NT-proBNP in plasma were detected by ELISA.Results Immunohistochemical staining showed positive expression of proBNP in both sudden death of coronary atherosclerotic heart disease group and single coronary stenosis group.There was no positive expression in normal control group.For sudden death of coronary atherosclerotic heart disease group and single coronary stenosis group,the relative expression of proBNP protein and BNP mRNA in myocardial tissue and the NT-proBNP content in plasma were higher than that of normal control group (P＜0.05).The NT-proBNP content in plasma of sudden death of coronary atherosclerotic heart disease group was higher than that of single coronary stenosis group (P＜0.05).Conclusion In myocardial ischemia condition,the higher expression of proBNP in cardiac muscle cell shows that the detection of NT-proBNP in plasma can be useful to differentially diagnose the degree of coronary atherosclerotic heart disease and determine whether the sudden death due to coronary atherosclerotic heart disease.

Histidine phosphorylation relieves copper inhibition in the mammalian potassium channel KCa3.1.

KCa2.1, KCa2.2, KCa2.3 and KCa3.1 constitute a family of mammalian small- to intermediate-conductance potassium channels that are activated by calcium-calmodulin. KCa3.1 is unique among these four channels in that activation requires, in addition to calcium, phosphorylation of a single histidine residue (His358) in the cytoplasmic region, by nucleoside diphosphate kinase-B (NDPK-B). The mechanism by which KCa3.1 is activated by histidine phosphorylation is unknown. Histidine phosphorylation is well characterized in prokaryotes but poorly understood in eukaryotes. Here, we demonstrate that phosphorylation of His358 activates KCa3.1 by antagonizing copper-mediated inhibition of the channel. Furthermore, we show that activated CD4(+) T cells deficient in intracellular copper exhibit increased KCa3.1 histidine phosphorylation and channel activity, leading to increased calcium flux and cytokine production. These findings reveal a novel regulatory mechanism for a mammalian potassium channel and for T-cell activation, and highlight a unique feature of histidine versus serine/threonine and tyrosine as a regulatory phosphorylation site.

Identification of PGAM5 as a Mammalian Protein Histidine Phosphatase that Plays a Central Role to Negatively Regulate CD4(+) T Cells.

Whereas phosphorylation of serine, threonine, and tyrosine is exceedingly well characterized, the role of histidine phosphorylation in mammalian signaling is largely unexplored. Here we show that phosphoglycerate mutase family 5 (PGAM5) functions as a phosphohistidine phosphatase that specifically associates with and dephosphorylates the catalytic histidine on nucleoside diphosphate kinase B (NDPK-B). By dephosphorylating NDPK-B, PGAM5 negatively regulates CD4(+) T cells by inhibiting NDPK-B-mediated histidine phosphorylation and activation of the K(+) channel KCa3.1, which is required for TCR-stimulated Ca(2+) influx and cytokine production. Using recently developed monoclonal antibodies that specifically recognize phosphorylation of nitrogens at the N1 (1-pHis) or N3 (3-pHis) positions of the imidazole ring, we detect for the first time phosphoisoform-specific regulation of histidine-phosphorylated proteins in vivo, and we link these modifications to TCR signaling. These results represent an important step forward in studying the role of histidine phosphorylation in mammalian biology and disease.

Effect of picroside H on mitochondria cytochrome C expression and its significance in rats after ischemia/reperfusion / 中华神经医学杂志

Objective To investigate the effect ofpicroside Ⅱ on mitochondria cytochrome C (CytC) expression and its significance in rats after ischemia/reperfusion.Methods Ninety-six Wistar rats were randomly divided into sham-operated group,model group,picroside Ⅱ group,Cyclosporin A (CsA,specific antgonist of CytC) group,CsA+picroside Ⅱ group,atractyloside (Atr,selective agonist of CytC) group,Atr+picroside Ⅱ group and DMSO group (n=12);the middle cerebral artery occlusion/reperfusion models referring to Longa's method with medications were adopted,which were established by inserting a monofilament suture into the internal carotid artery for 2 h and then reperfusion for 24 h.After 24 h of ischemia/reperfusion,modified neurological severity scale (mNSS) scores were observed,contents of reactive oxygen species (ROS) in brain tissues were measured by enzyme-linked immunosorbent assay (ELISA),morphology of brain tissues was observed by hematoxylin-eosin staining,ultrastructures ofmitochondria were observed by transmission electron microscopy,apoptotic cells were counted by terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL),and CytC expression was determined by immunohistochemical assay and Western blotting.Results As compared with the sham-operated group,the model group had significantly increased mNSS scores,ROS contents,number ofapoptotic cells and CytC expression (P＜0.05),and the mitochondria structure was seriously destroyed.The picroside Ⅱ group had obviously decreased mNSS scores,ROS contents,number of apoptotic cells and CytC expression,and the morphology of brain tissue was improved and the mitochondria damage was reduced as compared with the model group,with significant differences (P＜0.05).The Atr+picroside Ⅱ group had significantly decreased mNSS scores,ROS contents,number of apoptotic cells and CytC expression (P＜0.05),and the mitochondria damage in the Atr+picroside Ⅱ group was reduced as compared with that in the Atr group with significant difference (P＜0.05).Conclusion The mechanism of picroside Ⅱ protecting against focal cerebral ischemia reperfusion might attribute to decrease of ROS contents,protection of mitochondria structure and down-regulation of CytC expression in middle cerebral artery occlusion/reperfusion rats.

Effect of Picroside II on ERK1/2 Signal Pathway in Cerebral lschemic Injury Rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the neuroprotective effect and mechanism of picroside II on extracellular regulated protein kinases1/2 (ERK1/2) signal transduction pathway in cerebral ischemia injuryrats. METHODS The middle cerebral artery occlusion (MCAO) model was established by inserting a monofilament into middle cerebral artery. Totally 96 successfully modeled Wistar rats were divided into the modelgroup, the treatment (picroside II) group, the Lipopolysachcaride (LPS) group, and the U0126 group according to random digit table. Each group was further divided into 3 subgroups, i.e. 6, 12, and 24 h sub-groups. Picroside II (20 mg/kg) was peritoneally injected to rats in the treatment group 2 h after ischemia.LPS (20 mg/kg) and Picroside II (20 mg/kg) were peritoneally injected to rats in the LPS group 2 h after ischemia. U0126-EtOH (20 mg/kg)and Picroside II (20 mg/kg) were peritoneally injected to rats in the U0126group 2 h after ischemia. Equal volume of normal saline was peritoneally injected to rats in the control groupand the model group. The neurobehavioral function was evaluated by modified neurological severity score(mNSS) test. The structure of neurons was observed using hematoxylin-eosinstaining (HE) staining. Theapoptotic cells were detected using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expression of phosphorylated extracellular signal-regulated protein kinase1,2 (pERK1,2) in cortex was detected using immunohistochemistry (IHC) and Western blot.</p><p><b>RESULTS</b>After cerebral ischemia injury neurological impairment score increased, the damage of neuron in the cortical area was aggravated, apoptotic cells increased in the model group as time went by. The expression of pERK1/2 increased more significantly in the model group than in the control group (P <0.05). The damage of neuron in the cortical area was milder, while apoptotic cells decreased, the expression of pERK1f2 obviously decreased more in the treatment group and the U0126 group (P < 0.05). The early damage of neuron in the cortical area was more severe, apoptotic cells and the expression of pERK12 were comparatively higher in early stage of the LPS group, but the expression of pERK1/2 was somewhat decreased in late stage.</p><p><b>CONCLUSIONS</b>Activating ERK12 pathway could mediate apoptosis and inflammatory reactions of neurons after cerebral ischemia injury. Picroside II could protect the nerve system possibly through reducing activation of ERKI2 pathway, inhibiting apoptosis of neurons and inflammation reaction.</p>

Distribution and drug resistance of Escherichia coli producing extended-spectrumβlactamases in cancer patient / 国际检验医学杂志

Objective To study the distribution ,specimen types and characteristics of antibiotic resistance of Escherichia coli producing extended‐spectrum βlactamases(ESBLs) of the hospital in 2013 and to guide clinical drug use .Methods Analyzed the distribution and antibiotic resistance for the 375 strains of ESBLs‐producing E .coli ,and ESBLs was detected by disk diffusion phe‐notypic confirmatory test .Results The major distribution department was gynecology department which accounted for 42 .67% , followed by uropoiesis surgical department which accounted for 14 .67% ;the major specimen type was urine(55 .2% ) ,followed by puncture fluid(15 .47% )and excretion(14 .67% ) .For the 375 isolates of ESBLs‐producing E .coli ,the resistance rates to cefazolin , cefuroxime ,cefoperazone and cefotaxime were 100 .00% ,to SMZco was 78 .10% ,while the resistance rate to imipenem was 0 .00% , and to amikacin and fosfomycin were 4 .30% and 10 .10% respectvely ,the resistance rates to piperacillin/tazobactam and aztreonam were 17 .10% and 66 .70% respectvely .Conclusion ESBLs producing Escherichia coli have severe multidrug resistance .Antibiotics should be chosen and used rationally in accordance with results of drug susceptibility testing ,meanwhile the monitoring of ESBLs′infection rate and drug resistance should be strengthened .