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Sample records for ca 19-9 compared

  1. CA 19-9 (Cancer Antigen 19-9)

    Science.gov (United States)

    ... called Lewis antigen that is similar to the ABO antigens that are used in blood typing for transfusions. About 5% to 7% of people are Lewis antigen negative (about 30% in people of African ancestry) and do not produce CA 19-9. The CA 19-9 test is not useful for monitoring people who are ...

  2. Clinical Significance and Prognostic Value of CA72-4 Compared with CEA and CA19-9 in Patients with Gastric Cancer

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    M. Ychou

    2000-01-01

    Full Text Available Carcinoembryonic antigen (CEA and CA 19-9 are both widely used in the follow up of patients with gastrointestinal cancer. More recently another tumor marker, named CA 72-4 has been identified and characterized using two different monoclonal antibodies B72.3 and CC49. Several reports evaluated CA 72-4 as a serum tumor marker for gastric cancer and compared its clinical utility with that of CEA or CA 19-9; few reports concerned its prognostic value. In the present study, CA 72-4 is evaluated and compared with CEA and CA 19-9 in various populations of patients with gastric cancer and benign disease; for 52 patients with gastric adenocarcinoma and 57 patients without neoplastic disease CEA, CA 19-9 and CA 72-4 were evaluated before treatment. Sensitivity of the tumor markers CA 72-4, CA 19-9 and CEA at the recommended cut-off level in all 52 patients were 58%, 50% the sensitivity increased to 75%. of these markers, for non metastatic patients, multivariate analyses indicated that none of the markers were significant, when adjusted for gender and age (which were indicators of poor prognosis; patients with abnormal values of CA72-4 tended to have shorter survival than patients with normal values (p < 0.07. In the metastatic population, only high values of CA19-9 (p < 0.02 and gender (women (p < 0.03 were indicators of poor prognosis in univariate analysis; multivariate analysis revealed that both CA72-4 (p = 0.034 and CA19-9 p = 0.009, adjusted for gender were independent prognostic factors. However, CA72-4 lost significance (p = 0.41 when adjusted for CA19-9 and gender, indicating that CA19-9 provides more prognostic information than CA72-4.

  3. CA19-9antigenlevelscandistinguishbetween benignandmalignantpancreaticobiliarydisease

    Institute of Scientific and Technical Information of China (English)

    Gareth Morris-Stiff; Mary Teli; Nicky Jardine; Malcolm CA Puntis

    2009-01-01

    BACKGROUND: CA19-9 is a carbohydrate tumor-associated antigen which is frequently upregulated in pancreatobiliary neoplasia. However, it may also be elevated in patients with jaundice in the absence of a tumor due to biliary obstruction, and in other non-hepato-pancreatico-biliary conditions. This study aimed to evaluate whether CA19-9 levels could accurately differentiate between benign and malignant pancreatobiliary disease. METHODS: All patients referred to a single surgeon for investigation of pancreaticobiliary disease in 2003 in whom a ifrm diagnosis had been established were included. For malignant disease, a histological diagnosis was required but for benign disease a ifrm radiological diagnosis was deemed adequate. The patients were divided into 4 categories:pancreatic adenocarcinoma (PCa); cholangiocarcinoma (CCa); chronic pancreatitis (CP) and biliary calculous disease (Calc). Bilirubin and alkaline phosphatase levels corresponding to the point of assessment of CA19-9 were also noted. RESULTS:  Final diagnoses were made of pancreatic adenocarcinoma (PCa, n=73), cholangiocarcinoma (CCa, n=19), ampullary carcinoma (Amp, n=7), neuroendocrine carcinoma (Neu, n=4), duodenal carcinoma (Duo, n=3), chronic pancreatitis (CP, n=115), and biliary calculous disease (Calc, n=27). Median CA19-9 levels (U/ml) were:PCa, 653;CCa, 408;Duo, 403;Calc, 27;CP, 19;Neu, 10.5;Amp, 8 (reference range: 0-37). The CA19-9 levels were signiifcantly greater for malignant than for benign disease, could differentiate PCa from CCa/Duo, and were signiifcantly higher in unresectable than in resectable PCa. The sensitivity, speciifcity, positive predictive value (PPV) and negative predictive value (NPV) for CA19-9 were 84.9%, 69.7%, 67.7%and 86.1%, respectively. A ROC analysis provided an area under the curve for CA19-9 of 0.871 (0.820-0.922), giving an optimal CA19-9 of 70.5 U/ml for differentiating benign from malignant pathology. Using this cut-off, the sensitivity was 82

  4. Comparative study of CEA and CA19-9 in esophageal, gastric and colon cancers individually and in combination (ROC curve analysis)

    Institute of Scientific and Technical Information of China (English)

    Bhawna Bagaria; Sadhna Sood; Rameshwaram Sharma; Soniya Lalwani

    2013-01-01

    Objective:To determine the clinical serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases of esophageal, gastric, and colon cancers. Methods:The sensitivities of the two markers were compared individually and in combination, with specificity set at 100%. Receiver operating characteristic (ROC) curves were plotted. Results:Serum CEA levels were significantly higher in cancer patients than in the control group. The sensitivity of CEA was determined:in esophageal cancer, sensitivity=28%, negative predictive value (NPV)=61.72%, and AUC=0.742 (SE=0.05), with a significance level of P Conclusion:CEA exhibited the highest sensitivity for colon cancer, and CA19-9 exhibited the highest sensitivity for gastric cancer. Combined analysis indicated an increase in diagnostic sensitivity in esophageal and gastric cancer compared with that in colon cancer.

  5. The Reliability of Highly Elevated CA 19-9 Levels

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    B. R. Osswald

    1993-01-01

    Full Text Available CA 19-9 is used as a tumour marker of the upper gastrointestinal tract. However, extremely elevated CA 19-9 levels are found also in patients with benign diseases. Cholestasis was present in 97.1 % of patients with high elevated CA 19-9, independent of their primary disease. 50% of patients with non-malignant diseases and increased CA 19-9 levels showed liver cirrhosis, cholecystitis, pancreatitis and/or hepatitis. In 8.8% no explanation was found for the extremely high CA 19-9 level. The results provide evidence of different factors influencing the CA 19-9 level.

  6. Elevated serum CA 19-9 at screening tests: underlying conditions and role of abdominopelvic CT

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    Kim, Ji Yang [University of Louisville, Department of Radiology and Molecular Imaging Research Center, Louisville, KY (United States); Seoul National University Hospital, Department of Radiology, Healthcare System Gangnam Center, Seoul (Korea, Republic of); Kim, Se Hyung [Seoul National University Hospital, Department of Radiology and the Institute of Radiation Medicine, Seoul (Korea, Republic of); Kim, Soo Young [Seoul National University Hospital, Department of Radiology, Healthcare System Gangnam Center, Seoul (Korea, Republic of); Bundang CHA Hospital, Department of Radiology, Bundang (Korea, Republic of)

    2014-10-15

    To investigate underlying conditions of patients with elevated CA 19-9 at screening tests and to evaluate diagnostic performance of abdominopelvic CT. One hundred and thirteen patients with elevated CA 19-9 (>37 U/ml) who underwent abdominopelvic CT in a screening program were selected. Underlying conditions were determined by reviewing all available data and follow-up records. Patients were categorized into malignancy, benign, and normal/non-related disease groups. Their mean CA 19-9 and percent of patients with CA 19-9 ≥ 100 U/ml were compared. Diagnostic sensitivity of CT for detecting underlying conditions of elevated CA 19-9 was analysed. Seventeen patients (17/113, 15 %) had 17 elevated CA 19-9-related malignancies, and 55 patients (55/113, 48.7 %) had 70 benign diseases. Mean CA 19-9 and percent of patients with CA 19-9 ≥ 100 U/ml in the malignancy group were significantly higher than in the two other groups. CT detected all except one malignant lesion with a detection sensitivity of 94.1 % (16/17). Of 70 CA 19-9-related benign diseases, CT detected 34 benign diseases (48.6 %) providing an alternative diagnosis for elevated CA 19-9. Abdominopelvic CT is not only useful in detecting malignancies, but can also diagnose alternative benign causes of elevated CA 19-9 in asymptomatic screening tests. (orig.)

  7. Type 2 diabetes mellitus and CA 19-9 levels

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To prospectively investigate serum CA 19-9 levels in type 2 diabetic patients in comparison with age- and gender-matched control subjects. METHODS: We recorded duration of diabetes and examined fasting glucose levels, HbA1c levels and serum CA 19-9 levels in 76 type 2 diabetic patients and 76 controls. Abdominal CT was performed in order to eliminate abdominal malignancy in the diabetic and control groups. RESULTS: The average CA 19-9 level was 46.0 ± 22.4 U/mL for diabetic patients whereas it was 9.97 ± 7.1 U/mL for the control group (P < 0.001 ). Regression analysis showed a positive correlation between diabetes and CA 19-9 independent from age, gender, glucose level and HbA1c level (t = 8.8, P < 001 ). Two of the diabetic patients were excluded from the study because of abdominal malignancy shown by CT at the initial evaluation. For all patients, abdominal CT showed no pancreatic abnormalities. CONCLUSION: CA 19-9 is a tumor-associated antigen, which is elevated in pancreatic, upper gastrointestinal tract, ovarian hepatocellular, and colorectal cancers, as well as in inflammatory conditions of the hepatobiliary system, biliary obstruction and in thyroid diseases. Diabetes has been claimed to be a risk factor for pancreatic cancer, which is increasing its incidence and has one of the lowest survival rates of all cancers. CA 19-9 is used in the diagnosis of pancreatic cancer but is also a marker of pancreatic tissue damage that might be caused by diabetes. We propose that a higher cutoff value of CA 19-9 should be used in diabetics to differentiate benign and malignant pancreatic disease, and subtle elevations of CA 19-9 in diabetics should be considered as the indication of exocrine pancreatic dysfunction.

  8. Utility of serum CA19-9 in diagnosis of cholangiocarcinoma:In comparison with CEA

    Institute of Scientific and Technical Information of China (English)

    Xing-Lei Qin; Zuo-Ren Wang; Jing-Sen Shi; Min Lu; Lin Wang; Quan-Ru He

    2004-01-01

    AIM: The diagnosis of cholangiocarcinoma is often difficult,making management approaches problematic. A reliable serum marker for cholangiocarcinoma would be a useful diagnostic test. The aims of our study were to evaluate the usefulness of a serum CA19-9 determination in the diagnosis of cholangiocareinoma.METHODS: We prospectively measured serum CA19-9 and CEA concentrations in patients with cholangiocarcinoma (n=35), benign biliary diseases (n=92), and healthy individuals n=15). Serum CA19-9 and CEA concentrations were measured by an immunoradiometric assay without knowledge of the clinical diagnosis.were 77.14% and 68.57%, respectively. When compared with the benign biliary diseases group, the true negative rates of serum CA19-9 and CEA were 84.78% and 81.52%,respectively, The false positive rates of serum CA19-9 and CEA were 15.22% and 18.48%, whereas the accuracy of serum CA19-9 and CEA were 82.68% and 77.95%,respectively. Serum CA19-9 and CEA concentrations were significantly elevated (P<0.001 and P<0.05) in patients with patients undergoing curative resection of cholangiocareinoma,the mean serum CA19-9 concentration was decreased from however, no correlation was found between serum CEA and CA19-9 concentrations (r=0.036).CONCLUSION: These data suggest that the serum CA19-9 determination is a usefol addition to the available tests for the differential diagnosis of cholangiocareinoma. Serum CA19-9 is an effective tumor marker in diagnosing cholangiocareinoma,deciding whether the tumor has been radically resected and monitoring effect of treatment.

  9. [Carbohydrate antigens CA 19-9, CA 242, CA 50 in liver diseases].

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    Nowak, J; Jakubowska, D; Wiczkowski, A; Sprzaczkowska, K; Stechły, T; Zmudziński, W; Grzesik, P; Walas, R; Jarzab, B

    1998-01-01

    Serum concentrations of CA 19-9, CA 242, and CA 50 were determined in patients with hepatitis and liver cirrhosis without cholestasis. The study included 63 patients with chronic persistent hepatitis (group A), chronic active hepatitis (group B), and liver cirrhosis (group C). The control group (K) consisted of 82 patients with: peptic ulcer, colorectal polypi or diverticulosis of the colon. CA 19-9 level normal in the majority of patients with liver diseases, however, it was found to be increased in 4 (23%) of patients with liver cirrhosis. There was no statistically significant difference in the frequency of increased level of CA 19-9 between liver diseases and the control group. The rate of elevated serum level of CA 242 in patients with liver diseases and in control group was similar respectively 12%; 8.5%). The elevated CA 50 levels were most frequently found in patients with liver pathology (50% in liver cirrhosis and chronic active hepatitis; 36% in chronic persistent hepatitis). The elevation of CA 50 serum level occurs very often in liver diseases, even when they are going without cholestasis. Thus, the antigen is not useful for differentiating between benign and cancer diseases of gastrointestinal tract. Antigen CA 50 is to be taken into account only after exclusion of the pathology of liver, especially cirrhosis. Other investigated antigens: CA 19-9 and CA 242 are influenced by liver diseases to a minor and neglectable extent. Antigen CA 19-9 is the marker of choice in gastrointestinal cancers.

  10. Serum level of TSGF,CA242 and CA19-9 in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Jing-Ting Jiang; Chang-Ping Wu; Hai-Feng Deng; Ming-Yang Lu; Jun Wu; Hong-Yu Zhang; Wen-Hui Sun; Mei Ji

    2004-01-01

    AIM: To establish a method to detect the expression of the tumor specific growth factor TSGF, CA242 and CA19-9 in serum and evaluate their value in diagnosis of pancreatic cancer.METHODS: ELISA and Biochemical colorimetric assay were used to detect the serum content of TSGF, CA242 and CA19-9 in 200 normal cases, 52 pancreatitis patients and 96 pancreatic cancer patients.RESULTS: The positive likelihood ratios of TSGF, CA242and CA19-9 were 5.4, 12.6 and 6.3, respectively, and their negative likelihood ratios were 0.10, 0.19 and 0.17,respectively. With single tumor marker diagnosed pancreatic cancer, the highest sensitivity and specificity of TSGF were 91.6% and 93.5%. In combined test with 3 markers, when all of them were positive, the sensitivity changed to 77.0%and the specificity and the positive predictive value were 100%. The levels of TSGF and CA242 were significantly higher in the patients with pancreatic cancer of head than those in the patients with pancreatic cancer of body, tail and whole pancreas, but the expression of CA19-9 had no correlation with the positions of the pancreatic cancer. The sensitivity of TSGF, CA242 and CA19-9 was increased with the progress in stages of pancreatic cancer. In stage I, the sensitivity of TSGF was markedly higher than CA242 and CA19-9.CONCLUSION: The combined use of TSGF, CA242 and CA19-9 expressions can elevate the specificity for pancreatic cancer diagnosis. And it shows that it plays an important role to differentiate positions and tissue typing. It is a forepart diagnosis for the pancreatic cancer by combination checking.There is very important correlation between the three markers and the pancreatic cancer.

  11. EXPLORE ON DIAGNOSTIC AND PROGNOSTIC VALUES OF EXTRAHEPATIC CHOLANGIOCARCINOMA:UTILITY OF SERUM CA19-9 AND SERUM CEA

    Institute of Scientific and Technical Information of China (English)

    秦兴雷; 王作仁; 鲁敏; 王林; 何铨儒

    2004-01-01

    Objective To evaluate the validity of a serum carbohydrate antigen 19-9(CA19-9) determination in the diagnosis of extrahepatic cholangiocarcinoma(EHCC). Methods Serum CA19-9 concentration and serum carcinoembryonic antigen(CEA) concentration were prospectively measured by an immunoradiometric assay without knowledge of the clinical diagnosis in patients with EHCC (n=51), benign biliary diseases (n=42), and healthy individuals (n=15). Using a receiver operating characteristic (ROC) curve define a new strategy for interpreting CA19-9 and CEA in EHCC. Results The sensitivity of CA19-9 and CEA in diagnosing EHCC were 86.3% (44/51) and 25.5%(13/51), respectively. When compared with the benign biliary diseases group, the true negative rates of serum CA19-9 and serum CEA were 85.7% (36/42) and 95.2%(40/42), respectively. The false positive rates of serum CA19-9 and serum CEA were 14.3 %( 6/42) and 4.8 %( 2/42), whereas the accuracy of serum CA19-9 and serum CEA were 57.0%(53/93) and 86.0%(80/93), respectively. Serum CA19-9 concentration and serum CEA concentration were significantly elevated (P0.05), respectively. In 22 patients undergoing curative resection of EHCC, the mean serum CA19-9 concentration decreased from preoperative level of (456.6±120.4) kU·L-1 to postoperative level (62.8±17.3) kU·L-1(P<0.001). The outcomes showed that serum CA19-9 had greater diagnosis performances than serum CEA. Conclusion Serum CA19-9 is an effective tumor marker in diagnosing of cholangiocarcinoma, deciding whether the tumor has been radically resected and monitoring effect of treatment

  12. Comparison of Plasma Tu-M2-PK and CA19-9 in Pancreatic Cancer

    DEFF Research Database (Denmark)

    Joergensen, Maiken Thyregod; Heegaard, Niels H H; Schaffalitzky de Muckadell, Ove B

    2009-01-01

    because of suspicion of pancreatic cancer. Of these, 51 patients had their conditions diagnosed as PDAC, whereas this diagnosis was ruled out in 52 after 12 months of follow-up. The performance of Tu-M2-PK was compared with that of CA19-9 using cutoff values 15 and 37 U/mL, respectively. RESULTS...

  13. Prognostic significance of preoperative serum CA125, CA19-9 and CEA in gastric carcinoma

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    Wang, Wei; Chen, Xiao-Long; Zhao, Shen-Yu; Xu, Yu-Hui; Zhang, Wei-Han; Liu, Kai; Chen, Xin-Zu; Yang, Kun; Zhang, Bo; Chen, Zhi-Xin; Chen, Jia-Ping; Zhou, Zong-Guang; Hu, Jian-Kun

    2016-01-01

    The prognostic significance of preoperative serum CA125, CA19-9 and CEA in gastric carcinoma (GC) has been widely reported and is still under debate. Here, we evaluated the prognostic significance of preoperative serum CA125, CA19-9 and CEA in patients with GC. 1692 patients with GC who underwent gastrectomy were divided into the training (from January 2005 to December 2011, n = 1024) and the validation (from January 2012 to December 2013, n = 668) cohorts. Positive groups of CA125 (> 13.72 U/ml), CA19-9 (> 23.36 U/ml) and CEA (> 4.28 ng/ml) were significantly associated with more advanced clinicopathological traits and worse outcomes than that of negative groups (all P < 0.01). In Cox regression analysis, tumor size (P < 0.001, P = 0.005), pTNM stage (P < 0.001, P < 0.001) and CA125 (P = 0.026, P = 0.005) were independent prognostic factors both in two cohorts. Nomograms of these two cohorts based on the number of positive serum tumor markers (NPTM) were more accurate in prognostic prediction than TNM stage alone. Our findings suggested that elevated preoperative serum CA125, CA19-9 and CEA were associated with more advanced clinicopathological traits and less favorable outcomes. In addition, CA125 as an independent prognostic factor should be further investigated. Nomogram based on NPTM could accurately predict the prognosis of GC patients. PMID:27097114

  14. Comparison of circulating MMP-9, TIMP-1 and CA19-9 in the detection of pancreatic cancer

    DEFF Research Database (Denmark)

    Joergensen, Maiken Thyregod; Brünner, Nils; De Muckadell, Ove B Schaffalitzky

    2010-01-01

    Background/Aim: The performance of the circulating tumor markers carbohydrate antigen 19-9 (CA19-9), matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) were evaluated separately and in combination for their potential value in detecting pancreatic ductal...... adenocarcinoma. PATIENTS AND METHODS: The patients had symptoms of pancreatic cancer. The discriminative strength of MMP-9 and TIMP-1 were compared to that of CA19-9 using receiver operating characteristics curves, area under the curves (AUC), specificity and sensitivity. RESULTS: The sensitivities of MMP-9......, TIMP-1 and CA19-9 in detecting pancreatic ductal adenocarcinoma were 58.82%, 47.1% and 86%, respectively, with specificities of 34.6%, 69.2% and 73%. The AUCs of MMP-9, TIMP-1 and CA19-9 were 0.50, 0.64 and 0.84, respectively. Combining the three markers did not significantly improve detection...

  15. Developement of an Immunoradiometric Assay for Tumour Marker CA19-9

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A two-site sandwich immunoradiometric assay for quantifying CA19-9 in serum is developed byusing two monoclonal antibodies. One of CA19-9 antibodies is labeled with 125I as a tracer and the othermonoclonal antibody is immobilized on plastic tubes as the solid phase. The sensitivity of the assay is 2

  16. The diagnostic value of joint detection of serum CA19-9, CA125 and CA242 for cholangiocarcinoma

    Institute of Scientific and Technical Information of China (English)

    Cui Da-Peng; Han Lei; Liu Zhen-Xian; Yang He; Zhang Ying-Chun

    2016-01-01

    Objective:To study the diagnostic value of joint detection of serum CA19-9, CA125 and CA242 for cholangiocarcinoma.Methods:A total of 35 patients with cholangiocarcinoma who received surgical resection in our hospital were selected as malignant group, 30 patients with cholelithiasis who received surgical resection in our hospital during the same period were selected as benign group, serum samples were collected before surgery to determine CA19-9, CA125 and CA242 content, and cholangiocarcinoma tissue and normal bile duct tissue were collected after surgery to determine the content of proliferation and invasion molecules. Results:Serum CA19-9, CA125 and CA242 levels of malignant group were significantly higher than those of control group; PROX-1, Ki-67, Bcl-2, Bad, Gab1, LOXL2, TRPM7 and CXCL12 levels in cholangiocarcinoma tissue were higher than those in benign bile duct tissue, and E-cadherin level was lower than that in benign bile duct tissue; serum CA19-9, CA125 and CA242 levels were positively correlated with PROX-1, Ki-67, Bcl-2, Bad, Gab1, LOXL2, TRPM7 and CXCL12 levels, and negatively correlated with E-cadherin level.Conclusion:Joint detection of serum CA19-9, CA125 and CA242 can not only provide reference for the diagnosis of cholangiocarcinoma, but can also provide basis for the evaluation of proliferation, invasion and other malignant biological behaviors.

  17. Investigation of unexpected serum CA19-9 elevation in Lewis-negative cancer patients.

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    Hamada, Etsuko; Taniguchi, Terumi; Baba, Satoshi; Maekawa, Masato

    2012-05-01

    Cancer patients with a Lewis (a-b-) phenotype have no carbohydrate antigen 19-9 (CA19-9) in their serum. However, we found a small but distinct elevation in the serum CA19-9 level in three cancer patients with the Lewis-negative phenotype. Here, we investigated the reason of such phenomena. Six cancer patients with a Lewis-negative phenotype were selected by very low CA19-9 concentrations: three showed a small elevation (Group A) and the other three showed no elevation (Group B) in the serum CA19-9. We investigated the difference by analyzing the Lewis/Secretor genotypes. All of the six patients with a Le (a-b-) phenotype were genuine Le-negative genotypes: four individuals were homozygous for le1 (le(59,508)), one patient was compound heterozygous for le1 (le(59,508)) and le2 (le(59,1067)) and one patient was compound heterozygous for le1 and le(202,314). As for the Secretor gene, the three patients in Group B were homozygous for Se2 (one patient) or compound heterozygous for Se2 and sej (two patients), while the patients in Group A were all homozygous for sej genotypes. Even genuinely Le-negative patients, who genetically lack the Le enzyme and theoretically never produce CA19-9, occasionally show a slight increase in serum CA19-9 level when they are homozygous for Se-negative genotypes and suffer from advanced cancer with overproduction of glycans as precursors of CA19-9. Although such cases are not frequent, we should be acquainted with the correlation between serum CA19-9 values and genotypes of Lewis and Secretor genes.

  18. Huge splenic epidermoid cyst with elevation of serum CA19-9 level.

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    Matsumoto, Sayo; Mori, Toshifumi; Miyoshi, Jinsei; Imoto, Yoshitaka; Shinomiya, Hirohiko; Wada, Satoshi; Nakao, Toshihiro; Shinohara, Hisamitsu; Yoshida, Sadahiro; Izumi, Keisuke; Okazaki, Jun; Muguruma, Naoki; Takayama, Tetsuji

    2015-01-01

    A 30-year-old female was referred to our hospital for further examination of liver dysfunction. A huge, soft mass was noted in her left upper quadrant on physical examination. Abdominal ultrasonography and computed tomography revealed a huge cystic tumor of 20 cm in the hilus of the spleen. Serum CA19-9 was 491 U/ml, and splenectomy was performed under suspicion of a malignant cystic tumor. The inner surface of the cyst was lined by squamous epithelial cells that were immunohistochemically positive for CA19-9. Serum CA19-9 level was normalized after the surgery. Our case of a very rare, huge epidermoid cyst of the spleen suggests that measurement of the serum CA19-9 level is useful for evaluating therapeutic efficacy of a splenic epidermoid cyst.

  19. Elevated serum CA 19-9 levels in patients with pulmonary nontuberculous mycobacterial disease

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    Ji Young Hong

    2016-02-01

    Full Text Available Abstract Increased serum CA 19-9 levels in patients with nonmalignant diseases have been investigated in previous reports. This study evaluates the clinical significance of serum CA 19-9 elevation in pulmonary nontuberculous mycobacterial disease and pulmonary tuberculosis. The median CA 19-9 level was higher in patients with pulmonary nontuberculous mycobacterial disease than in patients with pulmonary tuberculosis (pulmonary nontuberculous mycobacterial disease: 13.80, tuberculosis: 5.85, p < 0.001. A multivariate logistic regression analysis performed in this study showed that Mycobacterium abscessus (OR 9.97, 95% CI: 1.58, 62.80; p = 0.014 and active phase of pulmonary nontuberculous mycobacterial disease (OR 12.18, 95% CI: 1.07, 138.36, p = 0.044 were found to be risk factors for serum CA 19-9 elevation in pulmonary nontuberculous mycobacterial disease. The serum CA 19-9 levels showed a tendency to decrease during successful treatment of pulmonary nontuberculous mycobacterial disease but not in pulmonary tuberculosis. These findings suggest that CA 19-9 may be a useful marker for monitoring therapeutic responses in pulmonary nontuberculous mycobacterial disease, although it is not pulmonary nontuberculous mycobacterial disease-specific marker.

  20. Elevated serum CA 19-9 levels in patients with pulmonary nontuberculous mycobacterial disease.

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    Hong, Ji Young; Jang, Sun Hee; Kim, Song Yee; Chung, Kyung Soo; Song, Joo Han; Park, Moo Suk; Kim, Young Sam; Kim, Se Kyu; Chang, Joon; Kang, Young Ae

    2016-01-01

    Increased serum CA 19-9 levels in patients with nonmalignant diseases have been investigated in previous reports. This study evaluates the clinical significance of serum CA 19-9 elevation in pulmonary nontuberculous mycobacterial disease and pulmonary tuberculosis. The median CA 19-9 level was higher in patients with pulmonary nontuberculous mycobacterial disease than in patients with pulmonary tuberculosis (pulmonary nontuberculous mycobacterial disease: 13.80, tuberculosis: 5.85, pdisease (OR 12.18, 95% CI: 1.07, 138.36, p=0.044) were found to be risk factors for serum CA 19-9 elevation in pulmonary nontuberculous mycobacterial disease. The serum CA 19-9 levels showed a tendency to decrease during successful treatment of pulmonary nontuberculous mycobacterial disease but not in pulmonary tuberculosis. These findings suggest that CA 19-9 may be a useful marker for monitoring therapeutic responses in pulmonary nontuberculous mycobacterial disease, although it is not pulmonary nontuberculous mycobacterial disease-specific marker.

  1. Pancreatic Mucinous Cyst Adenocarcinoma Producing CA 19-9. A Case Report

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    Sumiya Ishigami

    2007-03-01

    Full Text Available Context We herein present a rare case of a mucinous cystic neoplasm of the pancreas producing CA 19-9 and the clinical implications are discussed. Case report A 35-year-old woman with no history of abdominal surgery presented at Saisei Kai Sendai Hospital with an upper abdominal distention. Abdominal CT showed a large lobulated cystic tumor at the pancreatic tail. No distant metastases were identified. The preoperative serum CA 19-9 level was 6,200 U/mL (reference range: 0-37 U/mL. A mucinous cystic neoplasm of the pancreas was diagnosed and elective surgery was performed. On laparotomy, a round tumor 15 cm in diameter was encountered in the upper left abdomen. No invasion of neighboring organs or the portal vein was apparent. The entire tumor was curatively resected with a distal pancreatectomy. The final histopathological analysis revealed mucinous cystadenocarcinoma with no invasive component. Immunohistochemical staining disclosed CA 19-9 expression within the tumor cells. The CA 19-9 level normalized rapidly postoperatively and, although a minor pancreatic fistula occurred, this was resolved conservatively. She was discharged on the 45th postoperative day with no sign of tumor relapse; her CA 19-9 level was within the normal range 20 months postoperatively. Conclusion We present this rare case of a mucinous cystic neoplasm producing CA 19-9 and discuss the relevant literature. The CA 19-9 production in this tumor does not appear to be directly correlated to aggressive clinical behavior.

  2. Failure of CA19-9 to detect asymptomatic colorectal carcinoma.

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    Thomas, W M; Robertson, J F; Price, M R; Hardcastle, J D

    1991-06-01

    Serum CA19-9 levels have been measured in 34 patients with asymptomatic colorectal cancer, 39 age and sex matched subjects with healthy colons (as assessed at full colonoscopy) and 55 patients known to have liver metastases from primary colorectal cancers. In subjects with asymptomatic cancer the median CA19-9 was 12.75 U ml-1 (0.0-280.7 U ml-1), in the healthy controls the median CA19-9 was 12.80 U ml-1 (0.0-88.9 U ml-1) and in those with liver metastases was 62.5 U ml-1 (4.8-458.0 U ml-1). Levels were significantly higher in patients with metastatic disease than in patients with asymptomatic tumours or the healthy controls, however there was no significant difference between the asymptomatic group and the controls. Using an upper limit of normal of 37 U ml-1, the sensitivity of CA19-9 was 60.3% for the detection of colorectal cancer with liver metastases but only 17.6% for asymptomatic cancer. Serum CA19-9 estimation is of no value as a means of screening for asymptomatic colorectal cancer.

  3. Adjusting CA19-9 values to predict malignancy in obstructive jaundice: Influence of bilirubin and C-reactive protein

    Institute of Scientific and Technical Information of China (English)

    Gaetano La Greca; Maria Sofia; Rosario Lombardo; Saverio Latteri; Agostino Ricotta; Stefano Puleo; Domenico Russello

    2012-01-01

    AIM:To find a possible relationship between inflammation and CA19-9 tumor marker by analyzing data from patients with benign jaundice (BJ) and malignant jaundice (MJ).METHODS:All patients admitted for obstructive jaundice,in the period 2005-2009,were prospectively enrolled in the study,obtaining a total of 102 patients.On admission,all patients underwent complete standard blood test examinations including C-reactive protein (CRP),bilirubin,CA19-9.Patients were considered eligible for the study when they presented obstructive jaundice confirmed by instrumental examinations and increased serum bilirubin levels (total bilirubin > 2.0 mg/dL).The standard cut-off level for CA19-9 was 32 U/mL,whereas for CRP this was 1.5 mg/L.The CA19-9 level was adjusted by dividing it by the value of serum bilirubin or by the CRP value.The patients were divided into 2 groups,MJ and BJ,and after the adjustment a comparison between the 2 groups of patients was performed.Sensitivity,specificity and positive predictive values were calculated before and after the adjustment.RESULTS:Of the 102 patients,51 were affected by BJ and 51 by MJ.Pathologic CA19-9 levels were found in 71.7% of the patients.In the group of 51 BJ patients there were 29 (56.9%) males and 22 (43.1%) females with a median age of 66 years (range 24-96 years),whereas in the MJ group there were 24 (47%) males and 27 (53%) females,with a mean age of 70 years (range 30-92 years).Pathologic CA19-9 serum level was found in 82.3% of MJ.CRP levels were pathologic in 66.6% of the patients with BJ and in 49% with MJ.Bilirubin and CA19-9 average levels were significantly higher in MJ compared with BJ (P =0.000 and P =0.02),while the CRP level was significantly higher in BJ (P =0.000).Considering a CA19-9 cut-off level of 32 U/mL,82.3% in the MJ group and 54.9% in the BJ group were positive for CA19-9 (P =0.002).A CA19-9 cut-off of 100 U/mL increases the difference between the two groups:35.3% in BJ and 68.6

  4. CA 19-9 as a serum marker in urothelial carcinoma

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    Mahander Pall

    2012-01-01

    Conclusions: Serum CA19-9 is a marker of aggressiveness of urothelial carcinoma and is almost invariably raised in patients with metastatic disease. Thus, it may be used as a prognostic marker but not as a screening tool due to its low sensitivity.

  5. Two cases of the same family with the unusual elevation of CA19-9 levels.

    Science.gov (United States)

    Uyanik, Metin; Sertoglu, Erdim; Serdar, Muhittin A; Aydin, Fevzi N; Ozgurtas, Taner; Kurt, Ismail

    2014-01-01

    Introdução: O antigénio carbohidrato (CA19-9) presente no soro é um marcador amplamente utilizado na prática clínica e apresenta pequenos aumentos em algumas doenças benignas. Aqui relatamos dois casos saudáveis, uma mãe e a sua filha, com níveis CA19-9 um pouco elevados.Casos Clínicos: A mãe, com um nível CA19-9 elevado (89,90 U/mL; limite superior do intervalo normal (ULNR) plataformas de imunoensaios diferentes, em duplicado.Conclusão: As pessoas saudáveis podem ter níveis da CA19-9 superiores aos limites de referência. Portanto, os médicos precisam estar cientes dessas situações raras, sem falhar o diagnóstico de doenças malignas.

  6. Relationship between serum calcium and CA 19-9 levels in colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Peter Fuszek; Peter Lakatos; Adam Tabak; Janos Papp; Zsolt Nagy; Istvan Takacs; Henrik Csaba Horvath; Peter Laszlo Lakatos; Gabor Speer

    2004-01-01

    AIM: To examine the calcium metabolism of colorectal cancer(CRC) in patients with colorectal cancer and control patients.METHODS: Seventy newly diagnosed CRC patients were included. The healthy control group was age and gender matched (n=32). Particular attention was devoted to the relationship between serum calcium of patients, and levels of AFP, CEA, carbohydrate antigen 19-9 (CA 19-9) (that could be considered as prognostic factors). Furthermore, the Ca-sensing receptor (CaSR) gene A986S polymorphism was investigated in these patients, as well as the relationship between different CaSR genotypes and the data stated above.RESULTS: A lower level of ionized calcium (also corrected for albumin) was found in the serum of CRC patients with normal 25(OH) vitamin D levels. The ionized calcium concentration was inversely correlated with the serum level of CA 19-9. There was no difference in the distribution of CaSR genotypes, between CRC patients and general population. The genotypes did not correlate with other data examined.CONCLUSION: Based on these results, lower levels of serum calcium might be a pathogenic and prognostic factor in colorectal cancer.

  7. Marcador tumoral CA 19.9 aumentado sin evidencia de malignidad Elevated Ca 19.9 tumor marker without evidence of malignancy

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    Eduardo González Bosquet

    2007-06-01

    Full Text Available Los marcadores tumorales son de gran utilidad clínica en el seguimiento de los pacientes oncológicos. Su papel en el diagnóstico de tumoraciones malignas es controvertido. Presentamos un caso de una mujer con un quiste ovárico benigno en la cual los marcadores aumentan de forma inexplicable después de la extirpación del mismo.Tumor markers are a useful tool for surveillance of oncologic patients, whereas their role in the diagnosis of a malignancy is controversial. We present the case of a woman with a benign ovarian cyst with an unexpected elevation of Ca 19.9 after laparoscopic bilateral anexectomy.

  8. Enhanced discrimination of malignant from benign pancreatic disease by measuring the CA 19-9 antigen on specific protein carriers.

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    Tingting Yue

    Full Text Available The CA 19-9 assay detects a carbohydrate antigen on multiple protein carriers, some of which may be preferential carriers of the antigen in cancer. We tested the hypothesis that the measurement of the CA 19-9 antigen on individual proteins could improve performance over the standard CA 19-9 assay. We used antibody arrays to measure the levels of the CA 19-9 antigen on multiple proteins in serum or plasma samples from patients with pancreatic adenocarcinoma or pancreatitis. Sample sets from three different institutions were examined, comprising 531 individual samples. The measurement of the CA 19-9 antigen on any individual protein did not improve upon the performance of the standard CA 19-9 assay (82% sensitivity at 75% specificity for early-stage cancer, owing to diversity among patients in their CA 19-9 protein carriers. However, a subset of cancer patients with no elevation in the standard CA 19-9 assay showed elevations of the CA 19-9 antigen specifically on the proteins MUC5AC or MUC16 in all sample sets. By combining measurements of the standard CA 19-9 assay with detection of CA 19-9 on MUC5AC and MUC16, the sensitivity of cancer detection was improved relative to CA 19-9 alone in each sample set, achieving 67-80% sensitivity at 98% specificity. This finding demonstrates the value of measuring glycans on specific proteins for improving biomarker performance. Diagnostic tests with improved sensitivity for detecting pancreatic cancer could have important applications for improving the treatment and management of patients suffering from this disease.

  9. CA19-9 as a Potential Target for Radiolabeled Antibody-Based Positron Emission Tomography of Pancreas Cancer

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    Mark D. Girgis

    2011-01-01

    Full Text Available Introduction. Sensitive and specific imaging of pancreas cancer are necessary for accurate diagnosis, staging, and treatment. The vast majority of pancreas cancers express the carbohydrate tumor antigen CA19-9. The goal of this study was to determine the potential to target CA19-9 with a radiolabeled anti-CA19-9 antibody for imaging pancreas cancer. Methods. CA19-9 was quantified using flow cytometry on human pancreas cancer cell lines. An intact murine anti-CA19-9 monoclonal antibody was labeled with a positron emitting radionuclide (Iodine-124 and injected into mice harboring antigen positive and negative xenografts. MicroPET/CT were performed at successive time intervals (72 hours, 96 hours, 120 hours after injection. Radioactivity was measured in blood and tumor to provide objective confirmation of the images. Results. Antigen expression by flow cytometry revealed approximately 1.3×106 CA19-9 antigens for the positive cell line and no expression in the negative cell line. Pancreas xenograft imaging with Iodine-124-labeled anti-CA19-9 mAb demonstrated an average tumor to blood ratio of 5 and positive to negative tumor ratio of 20. Conclusion. We show in vivo targeting of our antigen positive xenograft with a radiolabeled anti-CA19-9 antibody. These data demonstrate the potential to achieve anti-CA19-9 antibody based positron emission tomography of pancreas cancer.

  10. Serum CA19-9 Level Associated with Metabolic Control and Pancreatic Beta Cell Function in Diabetic Patients

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    Haoyong Yu

    2012-01-01

    Full Text Available CA19-9 is a tumor-associated antigen. It is also a marker of pancreatic tissue damage that might be caused by diabetes. Long-term poor glycemic control may lead to pancreatic beta cell dysfunction which is reflected by elevated serum CA19-9 level. Intracellular cholesterol accumulation leads to islet dysfunction and impaired insulin secretion which provide a new lipotoxic model. This study firstly found total cholesterol was one of the independent contributors to CA19-9. Elevated serum CA19-9 level in diabetic patients may indicate further investigations of glycemic control, pancreatic beta cell function, and total cholesterol level.

  11. Serum CA19-9 Level Associated with Metabolic Control and Pancreatic Beta Cell Function in Diabetic Patients

    Science.gov (United States)

    Yu, Haoyong; Li, Ruixia; Zhang, Lei; Chen, Haibing; Bao, Yuqian; Jia, Weiping

    2012-01-01

    CA19-9 is a tumor-associated antigen. It is also a marker of pancreatic tissue damage that might be caused by diabetes. Long-term poor glycemic control may lead to pancreatic beta cell dysfunction which is reflected by elevated serum CA19-9 level. Intracellular cholesterol accumulation leads to islet dysfunction and impaired insulin secretion which provide a new lipotoxic model. This study firstly found total cholesterol was one of the independent contributors to CA19-9. Elevated serum CA19-9 level in diabetic patients may indicate further investigations of glycemic control, pancreatic beta cell function, and total cholesterol level. PMID:22778715

  12. Clinical evaluation of the tumor marker CA 19-9 in comparison with the carcinoembryonic antigen (CEA) for the surgical pre- and postoperative diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, M.; Hottenrott, C.; Encke, A.; Happ, J.; Maul, F.D.; Baum, R.P.; Hoer, G.

    1986-02-01

    A new tumor marker (CA 19-9) was investigated. CA 19-9 is a tumor-associated antigen which is detected by a monoclonal antibody. CA 19-9 (CIS-Centocor) was compared simultaneously with CEA (carcinoembryonic antigen) in 347 patients. 123 patients with gastrointestinal tumors showed a sensitivity of 31% for CA 19-9 (CEA 49%), combination increased sensitivity to 58%. The highest sensitivity was found in pancreas carcinoma (CA 19-9 75%, CEA 66%, combination 92%); it was lower in gastric, colon, and oesophagus carcinomas. In relapsed colorectal carcinomas sensitivity was 53% (CEA 78%, combination 85%). In cases of relapse, tumor markers may become positive even if they were not detectable before resection of the primary tumor. Specificity for CA 19-9 was 100% (CEA 84%) compared to a group of non-malignant diseases including patients with inflammations and patients with nicotin abuse (n=102). Because of its high specificity and superior sensitivity to CEA in pancreas carcinomas CA 19-9 should be determined in primary and relapse diagnosis in combination with CEA.

  13. Serum N-glycans outperform CA19-9 in diagnosis of extrahepatic cholangiocarcinoma.

    Science.gov (United States)

    Wang, Mengmeng; Fang, Meng; Zhu, Jianhui; Feng, Huijuan; Warner, Elisa; Yi, Changhong; Ji, Jun; Gu, Xing; Gao, Chunfang

    2017-07-28

    Extensive efforts have been devoted to improve the diagnosis of extrahepatic cholangiocarcinoma (ECCA) due to its silent clinical character and lack of effective diagnostic biomarkers. Specific alterations in N-glycosylation of glycoproteins are considered a key component in cancer progression, which can serve as a distinct molecular signature for cancer detection. This study aims to find potential serum N-glycan markers for ECCA. In total, 255 serum samples from patients with ECCA (n = 106), benign bile tract disease (BBD, n = 60) and healthy controls (HC, n = 89) were recruited. Only 2 μL of serum from individual patients was used in this assay where the N-glycome of serum glycoproteins was profiled by DNA sequencer-assisted fluorophore-assisted capillary electrophoresis (DSA-FACE) technology. Multi-parameter models were constructed by combining the N-glycans and carbohydrate antigen 19-9 (CA19-9) which is currently used clinically. Quantitative analyses showed that among 13 N-glycan structures, the bifucosylated triantennary N-glycan (peak10, NA3F2) presented the best diagnostic performance for distinguishing ECCA from BBD and HC. Two diagnostic models (Glycotest1 and Glycotest2) performed better than single N-glycan or CA19-9. Additionally, two N-glycan structures (peak9, NA3Fb; peak12, NA4Fb) were tightly related to lymph node metastasis in ECCA patients. In conclusion, sera of ECCA showed relatively specific N-glycome profiling patterns. Serum N-glycan markers and models are novel, valuable and noninvasive alternatives in ECCA diagnosis and progression monitoring. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Treatment of Ruptured Ovarian Endometrioma with Extremely High CA 125, Moderately High CA 19-9 and CA 15-3 Level

    Directory of Open Access Journals (Sweden)

    Muzeyyen Duran

    2013-06-01

    Full Text Available In this case report, a ruptured ovarian endometrioma with a very high CA-125 level, moderately elevated CA 19-9, and CA 15-3 levels is presented. A 20 years old patient, complaining from pelvic pain, 5 cm adnexial mass was detected on left side. Biochemical examination was revealed very high CA-125 value (2556IU/ml, moderately elevated CA 19-9 (134IU/ml, and CA 15-3 (65IU/ml values. Laparoscopy was done and a ruptured ovarian endometrioma of 5 cm was seen during operation. After the total excision of the cyst, tumor markers fell rapidly. Very high CA-125 value, moderately elevated CA19-9, and CA 15-3 values can be seen in cases with ruptured endometrioma. In young patients, endometrioma must be considered firstly and laparoscopy should be applied instead of more invasive methods unless there was any finding or strong suspicion about malignancy.

  15. Pancreatic Tuberculosis with Markedly Elevated CA 19-9 Levels: A Diagnostic Pitfall

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    Manveen Kaur

    2016-11-01

    Full Text Available Despite the high prevalence of tuberculosis (TB in developing countries, isolated pancreatic TB is rare and is usually seen in immunocompromised patients. It presents with non-specific signs and symptoms and may mimic malignancy both clinically and radiologically. Cytologic and histologic confirmation is required to establish the definitive diagnosis. We present a case of a 25-year-old male with a pancreatic mass and markedly elevated serum cancer antigen (CA 19-9 levels raising the suspicion of malignancy but with a histopathologic picture of TB. This case suggests that clinicians should have a heightened suspicion of pancreatic TB when faced with discrete pancreatic lesions even though elevated tumor markers may indicate malignancy. It is important to perform appropriate diagnostic testing and initiate antitubercular therapy early.

  16. Application of radio immunoassay of serum CA19-9 in carcinoma of digestive system%血清CA19-9免疫放射测定在消化系统肿瘤中的应用

    Institute of Scientific and Technical Information of China (English)

    范兰芳; 蔺小爱

    2001-01-01

    @@CA19-9(Carbohydrate antigen 19-9)是由胃、肠、胰及肝等脏器分泌的一种粘蛋白,是最基本最重要的糖蛋白型肿瘤标记物,属肿瘤相关抗原,当以上组织发生病变尤其是患恶性肿瘤时,其血清CA19-9处于高水平,比较体内CA19-9含量变化有利于及早发现上述有关脏器发生恶性肿瘤[1,2]。本研究采用IRMA法对145例患者血清CA19-9含量进行检测,比较胰腺癌、原发性肝癌、胃癌、黄疸及慢性胰腺炎等疾病中血清CA19-9水平差异,并探讨其临床意义。

  17. Five Year Results of US Intergroup/RTOG 9704 With Postoperative CA 19-9 {<=}90 U/mL and Comparison to the CONKO-001 Trial

    Energy Technology Data Exchange (ETDEWEB)

    Berger, Adam C., E-mail: adam.berger@jefferson.edu [Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Winter, Kathryn [RTOG Statistical Center, Philadelphia, Pennsylvania (United States); Hoffman, John P. [Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Regine, William F. [University of Maryland Medical Systems, Baltimore, Maryland (United States); Abrams, Ross A. [Rush University Medical Center, Chicago, Illinois (United States); Safran, Howard [Division of Hematology/Oncology, The Miriam Hospital, Providence, Rhode Island (United States); Freedman, Gary M. [Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Benson, Alan B. [Northwestern Memorial Hospital, Chicago, Illinois (United States); MacDonald, John [St. Vincent' s Comprehensive Cancer Center, New York, New York (United States); Willett, Christopher G. [Duke University Medical Center, Durham, North Carolina (United States)

    2012-11-01

    Purpose: Radiation Therapy Oncology Group (RTOG) trial 9704 was the largest randomized trial to use adjuvant chemoradiation therapy for patients with pancreatic cancer. This report analyzes 5-year survival by serum level of tumor marker CA 19-9 of {<=}90 vs >90 U/mL and compares results to the those of the CONKO-001 trial. Methods and Materials: CA 19-9 expression was analyzed as a dichotomized variable ({<=}90 vs >90 U/mL). Cox proportional hazard models were used to identify the impact of the CA 19-9 value on overall survival (OS). Actuarial estimates of OS were calculated using the Kaplan-Meier method. Results: Both univariate (hazard ratio [HR] = 3.2; 95% confidence interval [CI], 2.3-4.3, P<.0001) and multivariate (HR = 3.1; 95% CI, 2.2-4.2, P<.0001) analyses demonstrated a statistically significant decrease in OS for CA 19-9 serum level of {>=}90 U/mL. For patients in the gemcitabine (Gem) treatment arm with CA 19-9 <90 U/mL, median survival was 21 months. For patients with CA 19-9 {>=}90 U/mL, this number dropped to 10 months. In patients with pancreatic head tumors in the Gem treatment arm with RT quality assurance per protocol and CA 19-9 of <90 U/mL, median survival and 5-year rate were 24 months and 34%. In comparison, the median survival and 5-year OS rate for patients in the Gem arm of the CONKO trial were 22 months and 21%. Conclusions: This analysis demonstrates that patients with postresection CA 19-9 values {>=}90 U/mL had a significantly worse survival. Patients with pancreatic head tumors treated with Gem with CA 19-9 serum level of <90 U/mL and per protocol RT had favorable survival compared to that seen in the CONKO trial. CA 19-9 is a stratification factor for the current RTOG adjuvant pancreas trial (0848).

  18. 血清SccAg、CA125、CA19-9在宫颈癌及癌前病变中的表达及意义%Expressions and significances of serum SccAg, CA125, and CA19 -9 in cervical cancer and cervical precancerous lesion

    Institute of Scientific and Technical Information of China (English)

    甘玉杰; 熊小英; 符丽华; 谭玲玲

    2012-01-01

    Objective: To study the expressions and significances of serum squamous cell carcinoma antigen (SccAg) , cancer antigen 125 (CA125) , carbohydrate antigen 19-9 (CA19 -9) in cervical cancer and cervical precancerous lesion. Methods; Thirty-four serum samples in normal control group, one hundred and twenty - six serum samples in cervical intraepithelial neoplasia (CIN) group, and fifty - seven serum samples in cervical cancer group were detected, the three tumor markers in cervical cancer of different clinical stages, differentiation degrees, and pathological types were compared. Results; Serum SccAg expression changed in cervical precancerous lesion, the changes of CA125 and CA19 - 9 were not obvious. There was a positive correlation between serum SccAg level and clinical stages, pathological degrees, and lymph node metastasis of cervical cancer, CA125 and CA19 -9 had great application values in detection of cervical adeno-carcinoma. Conclusion; Comprehensively analyzing tumor markers can provide guidance and data for assisted diagnosis, diagnosis, treatment, and prognosis of the patients with cervical cancer.%目的:研究鳞状上皮细胞癌抗原(SccAg)、癌抗原125 (CA125)、癌抗原19-9 (CA19 -9)在癌前病变及宫颈癌中的表达和意义.方法:检测正常对照组血清34例、宫颈上皮内瘤变(CIN)组126例、宫颈癌组57例,对不同临床分期、分化程度和病理类型宫颈癌的三种肿瘤标志物进行比较.结果:SccAg在宫颈癌前病变已有变化,CA125和CA19 -9变化不明显,血清中SccAg的水平与肿瘤临床分期、肿瘤病理分级、淋巴结转移呈正相关,CA125和CA19 -9在检测腺癌中更有应用价值.结论:综合分析宫颈癌患者的肿瘤标志物能为患者的辅助诊断、病情诊治、预后提供指导信息.

  19. 小胰腺癌血清CA19-9测定及其临床意义%Detection and Clinical Significance of Serum CA19-9 for Small Pancreas Cancer

    Institute of Scientific and Technical Information of China (English)

    徐慧琴

    2001-01-01

    Objective: To determine the significance of serum CA19-9 for small pancreas cancer.Methods: The serum CA19-9 of 86 patients of pancreas cancer was detected. 18 patients of small pancreas cancer whose tumor diameter were less than 2 cm were received B ultrasound, CT, MRI and ERCP. Results: The serum CA19-9 positive rate was 61.1% in the patients of small pancreas cancer with its average value 140.5u/ml. The CA19-9 positive was common in the patient of small pancreas cancer with the lesion focus metastasis. There was no correlation between the serum CA19-9 and stage and tumor site of small pancreas cancer. Conclusion: The detection of serum CA19-9 might be helpful for the assessment of operative effect and supervision of follow-up after operation. The diagnostic positive rate of MRI and ERCP for small pancreas cancer should be higher than that of B ultrasound and CT. The combination detections of the serum CA19-9, MRI and ERCP could reach the purpose of early diagnosis.Early operation could reduce the mortality and improve the prognosis.%目的:明确血清CA19-9测定对小胰腺癌诊断的意义.方法:通过对86例胰腺癌患者血清CA19-9的检测,并对其中18例肿瘤直径≤2cm小胰腺癌)患者进行B超、CT、MRI及ERCP检测.结果:结果表明小胰腺癌患者血清CA19-9的阳性率为61.1%,平均值为140.5u/ml,病理显示CA19-9阳性多见于病灶有转移的小胰腺癌病人.血清CA19-9的阳性与小胰腺癌的病程,部位无关.结论:CA19-9检测有助于对手术疗效的评价与术后随访的监测.MRI、ERCP对小胰腺癌诊断阳性率明显高于B超、CT.联合应用血清CA19-9、MRI、ERCP 可达到早期诊断小胰腺癌的目的,而早期手术可降低死亡率,改善预后.

  20. Extraordinary elevated CA19-9 in patient with common bile duct stones and cholangitis Case report

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    Ali Mokhtarifar

    2012-05-01

    Full Text Available Serum Carbohydrate Antigen, CA19-9, is a carbohydrate antigen whose usage -as a tumor marker- in pancreatic and bile ducts malignancies is commonly increasing. Sensitivity and specificity of this antigen in the diagnosis of malignancies is 70-90% and 68-91%, respectively. CA19-9 can also rise in other disorders and in few of benign conditions including cholangitis, due to other causes, e.g. choledocholithiasis. However, in such cases the increase is not significant and it is usually below 1000 u/ml. Values more than 10000 u/ml are limited to few case reports in articles. The case under study was a 66 year old man hospitalized because of epigastric and right upper quadrant pain, fever, jaundice, acholic stool, weight loss of about 6 kg, and hyperchromic urine. Physical examination revealed that the case was icteric and febrile with a mild RUQ tenderness on percussion. Laboratory tests showed marked elevation of bilirubin and CA19-9 (Total bilirubin: 36 mg/dl, Direct: 19.5 mg/dl CA19-9 :44777u/ml, Normal: 0-40 u/ml, but the enzymes of the liver and alkaline phosphatase only increased to two times the normal level. Sonography showed dilated common bile duct with four stones within it. Four weeks after stones extraction and renewal of bile current CA19-9 fell to 60 u/ml and returned to normal range (0-40 2 months later and during this period the patient was totally asymptomatic. As a result, in patients with biliary obstruction, a diagnosis of malignancy cannot be made solely on the basis of increased concentration of CA19-9, even in case of high clinical suspicion and the interpretation of this increase must be done with more caution and after lab follow-up following removal of the obstruction.

  1. Utility of (18) F-FDG PET/CT and CECT in conjunction with serum CA 19-9 for detecting recurrent pancreatic adenocarcinoma.

    Science.gov (United States)

    Rayamajhi, Sampanna; Balachandran, Aparna; Katz, Mathew; Reddy, Arun; Rohren, Eric; Bhosale, Priya

    2017-09-12

    The roles of different cross-sectional imaging in evaluating the recurrence of pancreatic adenocarcinoma are not well established. We evaluated the utility of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced computed tomography (CECT) in the diagnosis of recurrent pancreatic adenocarcinoma in conjunction with the tumor marker CA 19-9. We retrospectively reviewed the records of patients who underwent CECT and FDG PET/CT along with serum CA 19-9 measurement as a follow-up or on a clinical suspicion of recurrent disease after initial surgery for pancreatic adenocarcinoma. Two observers blinded to the other imaging modality results retrospectively reviewed and interpreted the images in consensus using a three-point scale (negative, equivocal, or positive). Pathologic analysis by biopsy or further clinical and radiologic follow-up determined the true status of the suspected recurrences. The imaging results were compared with CA 19-9 levels and true disease status. Thirty-nine patients were included in the study. Thirty-three patients (85%) had proven recurrent cancer and six patients (15%) had no evidence of disease. Twenty-four patients had elevated CA 19-9 and 15 patients had normal CA 19-9. Sensitivity, specificity, and accuracy for recurrence were 90.9%, 100.0%, and 92.3% for PET/CT and 72.2%, 66.6%, and 71.7% for CECT, respectively. Sensitivity for locoregional recurrence was 94.4% for PET/CT but only 61.1% for CECT. PET/CT detected recurrence in 12 patients who had normal levels of CA 19-9. PET/CT showed lesions not visible on CECT in five (15%) patients. Although the sensitivity and specificity of PET/CT were higher than those of CECT, they were not statistically significant (p = 0.489 and p = 0.1489, respectively). FDG PET/CT has a high sensitivity for pancreatic cancer recurrence. Normal CA 19-9 does not necessarily exclude these recurrences. FDG PET/CT is useful when CECT is equivocal and can

  2. Clinical significance of detecting serum CA19-9,CEA,TGF-α and TGF-β1 in patients with pancreatic cancer%胰腺癌患者血清CA19-9、CEA、TGF-α和TGF-β1水平检测的临床意义

    Institute of Scientific and Technical Information of China (English)

    陆学安

    2014-01-01

    目的:探讨胰腺癌患者血清CA19-9、CEA、TGF-α和TGF-β1水平的变化及临床意义。方法:对30例胰腺癌患者应用放射免疫分析法进行血清 CA19-9、CEA、TGF-α和 TGF-β1水平检测,并与35例正常人比较。结果:胰腺癌患者血清 CA19-9、CEA、TGF-α和 TGF-β1水平均非常显著高于正常人组(P<0.01)。且血清 CA19-9水平与CEA、TGF-α、TGF-β1水平呈正相关(r=0.4925、0.6015、0.5984,P<0.01)。结论:对胰腺癌患者进行血清CA19-9、CEA、TGF-α和TGF-β1水平的检测并分析其变化情况,对疾病的诊断和治疗均有一定的临床价值。%Objective:To investigate the changes of serum CA19-9 CEA,TGF-α and TGF-β 1 in patients with pancreatic cancer and its clinical significanc.Methods:30 patients with pancreatic cancer were detected the level of serum CA19-9,CEA, TGF-α and TGF-β1 by radioimmunoassay,and they were compared with the levels of 35 normal people.Results:The levels of serum CA19-9,CEA, TGF-α and TGF-β1 in patient with pancreatic cancer were significantly higher than that of the normal group(P<0.01).And there were positively relationship between the level of serum CA19-9 and the levels of CEA,TGF-α, TGF-β1(r=0.4925,0.6015,0.5984,P<0.01).Conclusion:If we detected the levels of serum CA19-9,CEA,TGF-α and TGF-β1 in patients with pancreatic cancer and analyzed the changes of those levels,it can bring some certainly clinical values on the diagnosis and treatment of this diseases.

  3. The CA19-9 and Sialyl-TRA Antigens Define Separate Subpopulations of Pancreatic Cancer Cells.

    Science.gov (United States)

    Barnett, Daniel; Liu, Ying; Partyka, Katie; Huang, Ying; Tang, Huiyuan; Hostetter, Galen; Brand, Randall E; Singhi, Aatur D; Drake, Richard R; Haab, Brian B

    2017-06-22

    Molecular markers to detect subtypes of cancer cells could facilitate more effective treatment. We recently identified a carbohydrate antigen, named sTRA, that is as accurate a serological biomarker of pancreatic cancer as the cancer antigen CA19-9. We hypothesized that the cancer cells producing sTRA are a different subpopulation than those producing CA19-9. The sTRA glycan was significantly elevated in tumor tissue relative to adjacent pancreatic tissue in 3 separate tissue microarrays covering 38 patients. The morphologies of the cancer cells varied in association with glycan expression. Cells with dual staining of both markers tended to be in well-to-moderately differentiated glands with nuclear polarization, but exclusive sTRA staining was present in small clusters of cells with poor differentiation and large vacuoles, or in small and ill-defined glands. Patients with higher dual-staining of CA19-9 and sTRA had statistically longer time-to-progression after surgery. Patients with short time-to-progression (<2 years) had either low levels of the dual-stained cells or high levels of single-stained cells, and such patterns differentiated short from long time-to-progression with 90% (27/30) sensitivity and 80% (12/15) specificity. The sTRA and CA19-9 glycans define separate subpopulations of cancer cells and could together have value for classifying subtypes of pancreatic adenocarcinoma.

  4. The serum levels of tumor marker CA19-9, CEA, CA72-4, and NSE in type 2 diabetes without malignancy and the relations to the metabolic control

    Science.gov (United States)

    Shang, Xiaojing; Song, Chunqing; Du, Xiaoming; Shao, Hailin; Xu, Donghong; Wang, Xiaolai

    2017-01-01

    Objectives: To investigate whether there is a difference in carbohydrate antigen 19-9 (CA19-9), carcinoembryonic antigen (CEA), carbohydrate antigen 72-4 (CA72-4), and neuron-specific enolase (NSE) between diabetic and non-diabetic patients. Methods: A retrospective analysis was performed in 268 type 2 diabetic patients and 95 non-diabetic ones, and their serum levels of CA19-9, CEA, CA72-4, and NSE were compared in our endocrine ward at the Tianjin Fourth Central Hospital, Tianjin, China during the period from January to June 2015. The diabetic patients were divided into 4 groups based on glycosylated hemoglobin (HbA1c) levels to investigate the relationship between levels of tumor markers and glucose status. Results: Diabetic patients had higher levels of tumor markers than non-diabetic subjects (CA19-9: 13.0 versus 7.25U/mL, p=0.000; CEA: 2.55 versus 2.25 ng/mL, p=0.012; CA72-4: 1.95 versus 1.50U/mL, p=0.001; NSE: 11.64 versus 10.22ng/mL, p=0.000). CA19-9 levels increased in a stepwise manner with poor diabetes status. CEA levels were increased in patients with HbA1c ≥9% and CA72-4 elevation was predominant in patients with poor glycemic control (HbA1c ≥11%). NSE levels were not associated with metabolic parameters. Conclusion: Serum levels of CA19-9, CEA, CA72-4, and NSE were elevated in type 2 diabetes; however, only CA19-9, CEA, and CA72-4 levels were associated with hyperglycemia. PMID:28133696

  5. Benign Hydronephrosis and Elevated of Serum Levels of Carbohydrate Antigen CA 19-9: A Case Report

    Science.gov (United States)

    Filipovic, Branka; Milinić, Nikola; Gacic, Jasna; Markovic, Olivera; Djokovic, Aleksandra; Filipovic, Branislav

    2016-01-01

    Patient: Male, 58 Final Diagnosis: Hydronephrosis Symptoms: Blunt abdominal pain • constipation • constipation Medication: — Clinical Procedure: Extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy Specialty: Gastroenterology and Hepatology Objective: Rare co-existance of disease or pathology Background: Carbohydrate tumor-associated antigen (CA 19-9) has been shown to be upregulated in other malignant tumors including gastric, ovarian, hepatocellular, and colorectal carcinoma as well as benign diseases of the biliary track such as pancreatitis, cholangitis, and choledocholithiasis. According to the available literature, in several cases of benign hydronephrosis and in a few cases of benign renal diseases, elevated CA 19-9 has been noted. Case Report: A 58-year-old Caucasian male patient was admitted in our clinic with complaints about blunt abdominal pain in the past two-month period localized in the right lumbar region and irradiating into the right inguinal area, constipation, abdominal bloating, and intermittent hematuria. The concentration of serum CA 19-9 was 3500 U/mL. Urine cytology provided no signs of abnormality. Intravenous urography visualized right-sided pyelon and ureter duplex with the defect in contrast shade of the pyelon, caused by a stag horn calculus. Contrast added computerized axial tomography of the abdomen and pelvis visualized the pyelon casted concretion spreading throughout the right pyelon, with ureterohydronephrosis with the distal block for passage of the contrast to the distal part of the ureter. Conclusions: There is no doubt that CA 19-9 level is occasionally elevated in patients with obstructive urolithiasis as it was in our case. In the routine medical praxis, urolithiasis should not be neglected in the differential diagnosis of elevated concentrations of CA 19-9 marker. PMID:27287959

  6. Clinical value of serum CA19-9,CA125 and CP2 in mucinous ovarian tumor:a retrospective study of 273 patients%CA19-9CA125和CP2在卵巢黏液性肿瘤诊断和监测中的价值

    Institute of Scientific and Technical Information of China (English)

    董丽; 崔恒; 李小平; 孙丽芳; 昌晓红; 梁旭东; 祝洪澜

    2008-01-01

    125(+)与CA125(-)、CP2(+)与CP2(-)患者间生存率比较,差异有统计学意义(P<0.05);而CA19-9(+)与CA19-9(-)患者间生存率比较,差异则无统计学意义(P>0.05).结论 CA19-9是诊断卵巢黏液性肿瘤的敏感指标,与CA125联合检测可提高对卵巢黏液性肿瘤诊断的敏感度,并对术后监测有重要临床意义.CA125和CP2联合检测则对诊断卵巢非黏液肿瘤更敏感.%Objective To evaluate the diagnostic and prognostic value of serum CA19-9,CA125 and CP2 in mucinous ovarian tumors.Methods In this retrospective study,the serum CA19-9,CA125 and CP2 levels of 273 hospitalized patients with ovarian tumors of either mucinous or non-mucinous type were analyzed.Results(1)CA19-9 had the biggest area under chive(AUC)in mucinous tumors followed with CA125 while CA125 and CP2 had bigger AUC in non-mucinous tumor.(2)For the diagnosis of mucinous tumors,CA19-9 and CA125 combination showed a greatly increased sensitivity compared with CA19-9 or CA125 alone(93.8%versus 75.0%and 66.7%,P<0.05)with no significant improvement of the specificity(P>0.05).For the diagnosis of non-mucinous tumors,CA125 and CP2 combination showed an increased sensitivity compared with CA125 or CP2 alone(85.0%versus 80.7%,P>0.05,85.0%versus 70.6%,P<0.05)with no significant improvement of the specificity(P>0.05).(3)Seventy percent of tumor marker-positive patients could undergo cytoreductive surgery.Compared with those who could not undergo cytoreductive surgery,they were more likely to have normal tumor marker two months after surgery (P<0.05)and longer interval to re-elevation of tumor markers(P>0.05),with lower reeurrence and death rate (P<0.05).All of the 20 tumor marker-negative patients could have eytoreduetive surgery with only 10%recurrence.(4)CA19-9 inereased mainly in recurrent mucinous tumor,while CA125 increased dominantly in recurrent non-mueinous tumor.(5)The survival rate of CA125 and CP2 positive patients was much lower than CA125

  7. Metabolic tumour burden assessed by {sup 18}F-FDG PET/CT associated with serum CA19-9 predicts pancreatic cancer outcome after resection

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hua-Xiang; Chen, Tao; Wang, Wen-Quan; Wu, Chun-Tao; Liu, Chen; Long, Jiang; Xu, Jin; Liu, Liang; Yu, Xian-Jun [Fudan University, Shanghai Cancer Center, Pancreatic Cancer Institute and Department of Pancreatic and Hepatobiliary Surgery, Shanghai (China); Fudan University, Department of Oncology, Shanghai Medical College, Shanghai (China); Zhang, Ying-Jian [Fudan University, Shanghai Cancer Center, Department of Nuclear Medicine, Shanghai (China); Fudan University, Department of Oncology, Shanghai Medical College, Shanghai (China); Chen, Run-Hao [Fudan University, Department of General Surgery, Jinshan Hospital, Shanghai (China)

    2014-06-15

    Tumour burden is one of the most important prognosticators for pancreatic ductal adenocarcinoma (PDAC). The aim of this study was to investigate the predictive significance of metabolic tumour burden measured by {sup 18}F-FDG PET/CT in patients with resectable PDAC. Included in the study were 122 PDAC patients who received preoperative {sup 18}F-FDG PET/CT examination and radical pancreatectomy. Metabolic tumour burden in terms of metabolic tumour volume (MTV) and total lesion glycolysis (TLG), pathological tumour burden (tumour size), serum tumour burden (baseline serum CA19-9 level), and metabolic activity (maximum standard uptake value, SUVmax) were determined, and compared for their performance in predicting overall survival (OS) and recurrence-free survival (RFS). MTV and TLG were significantly associated with baseline serum CA19-9 level (P = 0.001 for MTV, P < 0.001 for TLG) and tumour size (P < 0.001 for MTV, P = 0.001 for TLG). Multivariate analysis showed that MTV, TLG and baseline serum CA19-9 level as either categorical or continuous variables, but not tumour size or SUVmax, were independent risk predictors for both OS and RFS. Time-dependent receiving operating characteristics analysis further indicated that better predictive performances for OS and RFS were achieved by MTV and TLG compared to baseline serum CA19-9 level, SUVmax and tumour size (P < 0.001 for all). MTV and TLG showed strong consistency with baseline serum CA19-9 level in better predicting OS and RFS, and might serve as surrogate markers for prediction of outcome in patients with resectable PDAC. (orig.)

  8. Laparoscopic diagnosis and treatment of pelvic benign multicystic mesothelioma associated with high CA19.9 serum concentration.

    Science.gov (United States)

    Pinto, Vincenzo; Rossi, Angela Cristina; Fiore, Maria Grazia; D'Addario, Vincenzo; Cicinelli, Ettore

    2010-01-01

    We report a case of benign multicystic mesothelioma in a 20-year-old woman referred because of amenorrhea. She underwent pelvic transabdominal ultrasound, which disclosed a micropolycystic appearance of the ovaries and a fluid collection in the pouch of Douglas. Tumor serum markers revealed an increase in CA19.9. Abdominal and pelvic computed tomography scans confirmed the presence of ascites. Laparoscopy disclosed small, thin-walled, translucent cysts in the Douglas cavity. The cysts were free-floating in a yellowish, sticky, gelatinous material. Microscopically, cystic lesions showed mesothelium-lined cystic spaces surrounded by a delicate thin fibrovascular wall. With immunohistochemistry, the tumor cells were strongly positive for cytokeratin and calretinin. These aspects were suggestive of benign multicystic mesothelioma. Electron microscopy confirmed the mesothelial nature of this tumor. Serial evaluation of the CA19.9 concentration showed a progressive decrease in the serum marker in the normal range. The patient is now well and symptom-free with no recurrence 24 months after surgery. The association between benign multicystic mesothelioma and increased CA19.9 serum concentration has been described only once, in a man. To our knowledge, this is the second case of benign multicystic mesothelioma associated with increased CA19.9 serum concentration and the first diagnosed in a woman. In the present case, a minimally invasive laparoscopic approach enabled not only histologic diagnosis of benign multicystic mesothelioma but also its surgical treatment. Although benign multicystic mesothelioma is a rare pathologic entity, it is important that sonologists include it in the differential diagnosis of diseases that manifest with ascites. Furthermore, all surgeons should be aware of the macroscopic and laparoscopic appearance of the lesion, and its generally benign course. Copyright 2010 AAGL. Published by Elsevier Inc. All rights reserved.

  9. Application value discussion of CEA, CA19-9, CA242, CA72-4 in early diagnosis of rectal cancer%CEA、CA19-9CA242、CA72-4在直肠癌早期诊断的应用价值探讨

    Institute of Scientific and Technical Information of China (English)

    周永玲

    2015-01-01

    目的:探讨联合检测癌胚抗原(CEA)、糖类抗原19-9(Carbohydrate antigen 19-9CA19-9)、糖类抗原242(carbohydrate antigen 242,CA242)、糖类抗原72-4(Carbohydrate antigen 72-4,CA72-4)对直肠癌早期诊断价值。方法采用化学发光法联合检测直肠癌组、直肠良性病变组和健康对照组血清中 CEA、CA19-9CA242、CA72-4浓度,并进行统计学分析。结果直肠癌组患者血清中 CEA、CA19-9CA242、CA72-4的含量均明显高于直肠良性病变组及健康对照组,差异有统计学意义(P<0.05),直肠良性病变组和健康对照组比较差异无统计学意义,直肠癌组患者血清四项标志物联合检测的阳性率:72.587%(45/62)高于 CEA 单项检测的阳性率61.29%(38/62)。结论联合检测血清中 CEA、CA19-9CA242、CA72-4含量可有显著的互补性效提高直肠癌的诊断诊断率,是早期筛查直肠癌一中简单,有效的方法。%Objective To investigate early diagnosis value of CEA, CA19-9, CA242, CA72-4 for rectal cancer. Methods applying chemiluminescence combined with testing serum concentrations of CEA,CA19-9,CA242,CA72-4 of rectal cancer, rectal benign lesion, health control group, and carry on statistical analyis. Result CEA, CA19-9, CA242 and CA72-4 contents in serum of rectal cancer groups were significantly higher than rectal benign lesion and healthy control group, and difference shows statistical significance(P<0.05). Comparison between rectal benign lesion and healthy control group shows no statistical significance. And positive rate of combination test for four markers in serum of rectal cancer group was 72.587% (45/62), which was higher than 61.29% (38/62) of CEA test only. Conclusion combination test for CEA, CA19-9, CA242 and CA72-4 contents can significantly improve diagnostic rate of rectal cancer, which is a simple and effective method for early screening of rectal cancer.

  10. Combined detection of CEA, CA19-9 and CA125 in the differential diagnosis of benign and malignant ascites%联合检测CEA、CA19-9CA125对鉴别良恶性腹水的价值

    Institute of Scientific and Technical Information of China (English)

    卢冰贤; 周云英

    2011-01-01

    目的 探讨检测CEA(癌胚抗原)、CA19-9(糖类抗原19-9)和CA125(糖类抗原125)对鉴别良、恶性腹水的临床价值. 方法 化学发光法检测120例患者腹水CEA、CA19-9CA125的含量. 结果 化学发光法检测恶性腹水中的CEA、CA19-9CA125分别为(37±16) ng/ml、(236±78) U/ml和(602士211)U/ml,良性腹水分别为(13±2)ng/ml、(34士3)U/ml和(32±3)U/ml,差异均有统计学意义(P<0.05).同时,3种抗原检测的敏感性和特异性各有特点,需要联合检测. 结论 联合检测良、恶性腹水中CEA、CA19-9CA125水平对鉴别诊断有一定临床意义.%Objective To explore the clinical value of detecting CEA (cancer embryo antigen), CA19-9 (sugar 19-9 antigen), and CA125 (sugar antigen 125) to differentiate benign and malignant ascites. Methods CA19-9, CEA, and CA125 levels were determined by chemiluminescence detection in 120 patients with ascites. Results Chemiluminescence of patients with malignant ascites revealed a CEA level of (37± 16) ng/ml, a CA19-9 level of (236±78) U/ml, and a CA125 level of (602 + 211) U/ml while chemiluminescence of patients with benign ascites revealed a CEA level of (13± 2) ng/ml, a CA19-9 level of (34±3) U/ml and a CA125 level of (32 ± 3) U/ml. Differences were statistically significant (P<0. 05). Testing with 3 different antigens revealed a particular sensitivity and specificity, and combined testing was required. Conclusion Combined testing of CA19-9, CEA, and CA125 levels has some clinical significance in the differential diagnosis of benign and malignant ascites.

  11. Decline in CA19-9 during chemotherapy predicts survival in four independent cohorts of patients with inoperable bile duct cancer

    DEFF Research Database (Denmark)

    Grunnet, Mie; Christensen, Ib J; Lassen, Ulrik;

    2015-01-01

    BACKGROUND: Carbohydrate associated antigen (CA19-9) has been approved by the FDA as a biomarker for monitoring treatment effect in pancreatic cancer. However, the value of serum CA19-9 as a biomarker of response to chemotherapy in bile duct cancer is unclear. The aim of this study was to determine...

  12. Logistic回归和ROC曲线评价甲胎蛋白、癌胚抗原和糖链抗原19-9在肝癌诊断中的价值%The value of assessing AFP and CEA and CA19 -9 by using logistic regression and ROC curve in the diagnosis of liver cancer

    Institute of Scientific and Technical Information of China (English)

    戴大飞; 陈晓鹏

    2016-01-01

    目的 探讨应用Logistic回归和ROC曲线综合评价甲胎蛋白( AFP)、癌胚抗原( CEA)和糖链抗原19-9(CA19-9)在肝癌诊断中的价值. 方法 采用电化学发光原理测定AFP、CEA、CA19-9. 检测126例肝癌患者(肝癌组)、75例肝病患者(肝病组) ,通过ROC曲线分析AFP、CEA、CA19-9及三种肿瘤标志物联合检测的Logistic回归结果的ROC曲线值( AUC值). 结果 肝癌-肝良性疾病者中,除CEA外,其余2种肿瘤标志物均有显著性(P0.05). 在肝癌-肝良性疾病中,AUC( AFP) >AUC ( CA19-9)>AUC( CEA);三种肿瘤标志物联合检测的AUC值均高于三项肿瘤标志物单一检查的AUC.结论 联合检测血清AFP、CEA、CA19-9对肝癌具有较高的诊断价值,联合检测三种肿瘤标志物可提高肝癌的诊断率.%Objective To explore the value of assessing AFP and CEA and CA19 -9 by logistic regression and ROC curve in the diagnosis for liver cancer.Methods Serum AFP, CEA and CA19-9 ( using CLIA) levels were measured in 126 patients with liver cancer, 75 patients with benign liver disorders.The area under the ROC curves ( AUC ) of AFP, CEA and CA19 -9 from logistic regression results was compared.Results The serum concentrations of AFP and CA19 -9 in liver cancer patients were higher than those in patients with benign liver diseases (P0.05).In cancer-benign disorder group, the AUC of AFP was larger than the AUC of CA199.the AUC of CA19-9 was larger than the AUC of CEA.AUC value of AFP, CEA and CA19-9 combination detection was larger than AUC value of AFP, CEA and CA19-9 single detection.Conclusions The combination detection of serum AFP, CEA and CA19-9 have higher diagnostic value in liver cancer, also can improve the diagnosis rate of liver cancer.

  13. Effect of paclitaxel liposome combined with nedaplatin on serum HE4, CA125, CA19-9, AFP, CEA and T lymphocyte subsets in patients with advanced ovarian cancer

    Institute of Scientific and Technical Information of China (English)

    Su-Yu Zhu; Jie Tan; Chen-Lu Zhang; Qun-Ying Wu; Xue-Xin Xie; Hua-Fang Yin

    2016-01-01

    Objective:To study the effect of paclitaxel liposome combined with nedaplatin on serum HE4, CA125, CA19-9, AFP, CEA and T lymphocyte subsets in patients with advanced ovarian cancer.Methods:A total of 80 patients with advanced ovarian cancer in our hospital from December 2012 to December 2015 were enrolled in this study. The subjects were divided into control group (n=40) and experiment group (n=40) randomly. The control group were treated with paclitaxel and cisplatin, the experiment group were treated with paclitaxel liposome combined with nedaplatin. 21 days for a period of treatment and the two groups were treated for 3 periods. The serum HE4, CA125, CA19-9, AFP, CEA levels and peripheral blood CD3+, CD4+, CD8+ and NK cells of the two groups before and after treatment were compared. Results:There were no significantly differences of the serum HE4, CA125, CA19-9, AFP, CEA level and peripheral blood CD3+, CD4+, CD8+ and NK cells of the two groups before treatment (P>0.05). The serum HE4, CA125, CA19-9, AFP and CEA level of the two groups after treatment were significantly lower than before treatment (P<0.05), and that of experiment were significantly lower than control group (P<0.05). The peripheral blood CD3+, CD4+, CD8+and NK cells of the two groups after treatment were significantly lower than before treatment (P<0.05), and that of experiment were significantly higher than control group (P<0.05). Conclusions:Paclitaxel liposome combined with nedaplatin can significantly reduce the serum HE4, CA125, CA19-9, AFP and CEA levels, improve peripheral blood CD3+, CD4+, CD8+ and NK levels of patients with advanced ovarian cancer, and it was worthy clinical application.

  14. Menstrual Cycle Dependent Variability for Serum Tumor Markers CEA, AFP, CA 19-9, CA 125 and CA 15-3 in Healthy Women

    Directory of Open Access Journals (Sweden)

    Ayşe Binnur Erbağci

    1999-01-01

    Full Text Available Information on menstrual cycle dependent variation of tumor markers in healthy women is a subject of diagnostic efficiency and has an impact in elucidating the normal function of these markers. In this study midfollicular and midluteal concentrations of serum CEA, AFP, CA 19-9, CA 125, CA 15-3 and their relations with LH, FSH, prolactin, estradiol and progesterone were evaluated during ovulatory cycles in a group of 23 healthy female individuals. Samples were collected on the 7th and 21st day of the same menstrual cycle. Tumor marker and hormone concentrations were determined with chemiluminescence or electrochemiluminescence EIA methods. A significant phase-dependent difference was observed for CA 15-3, midluteal concentrations (mean ± SEM; 26.33 ± 1.56 U/ml higher than the midfollicular (mean ± SEM; 19.27 ± 1.49 U/ml concentrations (p < 0.001. But an obvious difference for other tumor markers investigated did not exist. Significant correlations of follicular and luteal CA 125 levels with body mass index of the subjects were observed (r:0.52, p < 0.05 and r:0.57, p < 0.005, respectively.

  15. Levels of carcinoembryonic antigen and CA 19-9 in the sera and peritoneal washing of patients undergoing surgical treatment for gastric carcinoma Níveis do antígeno carcinoembriônico e do CA 19-9 no soro e no lavado peritonial em doentes submetidos ao tratamento cirúrgico do carcinoma gástrico

    Directory of Open Access Journals (Sweden)

    René Crepaldi-Filho

    2008-09-01

    Full Text Available BACKGROUND: Early peritoneal recurrence of gastric carcinoma following curative resection remains a great challenge in the treatment and prevention of this disease. AIM: To analyze the relationship between levels of tumor markers, carcinoembryonic antigen (CEA and CA 19-9 in the sera and peritoneal washing, and anatomopathological aspects of the gastric carcinoma. METHODS: Of the 46 patients in the study, 29 (63.0% were males and 17 (37.0% females. Mean age was 63.6 ± 11.7 years (31 to 91 years. Peripheral venous blood samples were collected from the upper limb vein from both patient groups after anesthetic induction, in order to determine serum levels of CEA and CA 19-9. After the end of the procedure, 50 mL of physiologic solution was introduced into the bottom of the Douglas sack and a portion aspirated to determine CEA and CA 19-9 levels in the peritoneal washing. Levels of CEA and CA 19-9 in the sera and peritoneal washing were compared to the following variables: lesion diameter ≤4 cm or >4 cm, lymph node involvement, angiolymphatic invasion, depth of invasion into gastric wall, and initial or late stage. RESULTS: Sera CEA levels were significantly higher in patients with lesions >5 cm. CEA levels in the sera and peritoneal washing were significantly greater in patients with signet ring cell gastric carcinoma. In addition, levels of CEA in peripheral blood and peritoneal washing showed significant association with the degree of carcinoma penetration into the gastric wall, while sera CEA was significantly higher in patients at more advanced stages. There was no significant difference between sera and peritoneal CEA values regarding grade of differentiation. Patients with gastric lesions measuring > 5cm and more differentiated lesions had significantly higher sera CA 19-9 values. In patients with lymph nodes invasion by gastric carcinoma, CA 19-9 levels in peritoneal washing were significantly higher than in peripheral blood. Levels of CA

  16. SF、CEA、CA15-3、CA19-9、SCC及SF+CEA联检对肺癌的诊断价值

    Institute of Scientific and Technical Information of China (English)

    宋清玲; 雷光文

    2011-01-01

    @@ 近年来的研究表明,血清铁蛋白(SF)在肿瘤细胞中含量丰富,SF增高可作为恶性肿瘤的辅助实验诊断指标.因此,SF的测定在临床的应用越来越受到重视.本文对肺癌患者进行血清SF、CEA、CA15-3、 CA19-9鳞状上皮细胞癌抗原(SCC)及SF+CEA联检,以探讨肺癌的早期诊断.

  17. Positive predictive value of CEA and Ca19-9 as tumor markers for recurrent colorectal cancer in cases where conventional work-up fail to localize disease.

    Directory of Open Access Journals (Sweden)

    Yana Bocheva

    2015-12-01

    Full Text Available Introduction: Routine surveillance of colorectal cancer includes serial measurements of CEA levels. Although not routinely indicated Ca 19-9 is also a tool for recurrence. When any of these serum markers is elevated during follow up, this could represent a recurrence. The management of elevated tumor marker levels include clinical exams, endoscopy and conventional imaging –ultrasound, CT, MRI.Objective: To evaluate the positive predictive value of CEA and Ca19-9 as tumor markers for recurrent colorectal cancer in cases where conventional imaging and endoscopic studies fail to localize disease.Materials and methods: A total of 75 patients with elevated CEA and/or Ca19-9 serum levels and negative endoscopic exam as well as negative abdominal CT and Chest X-ray were included in the study. CEA levels were tested in 50 patients. Ca 19-9 was tested in 65 patients. 34 of the patients had both markers tested. All patients underwent whole body 18F-FDG PET/CT. Patients with negative of equivocal PET scan were further followed up (10 to 24 months.Results: Based on the reference standard – the results from PET/CT, if positive and the results from follow-up in cases of negative or equivocal scans, the positive predictive value of Ca 19-9 was 84% and that of CEA -83%. There was no significant difference in the PPV of Ca19-9 and CEA.Conclusion: Elevated CEA and Ca 19-9 levels in patients under active surveillance after operation for colorectal cancer have high positive predictive value for recurrence, even in cases where conventional work-up – endoscopy and CT don’t localize disease.

  18. The effect of high level natural ionizing radiation on expression of PSA, CA19-9 and CEA tumor markers in blood serum of inhabitants of Ramsar, Iran.

    Science.gov (United States)

    Heidari, Mohammad Hassan; Porghasem, Mohsen; Mirzaei, Nazanin; Mohseni, Jafar Hesam; Heidari, Matine; Azargashb, Eznollah; Movafagh, Abolfazl; Heidari, Reihane; Molouki, Aidin; Larijani, Leila

    2014-02-01

    Since several high level natural radiation areas (HLNRAs) exist on our planet, considerable attention has been drawn to health issues that may develop as the result of visiting or living in such places. City of Ramsar in Iran is an HNLRA, and is a tourist attraction mainly due to its hot spas. However, the growing awareness over its natural radiation sources has prompted widespread scientific investigation at national level. In this study, using an ELISA method, the level of expression of three tumor markers known as carcinoembryonic antigen (CEA), prostate-specific antigen (PSA) and carcino antigen 19-9 (CA19-9) in blood serum of 40 local men of Ramsar (subject group) was investigated and compared to 40 men from the city of Noshahr (control group). Noshahr was previously identified as a normal level natural radiation area (NLNRA) that is some 85 km far from Ramsar. According to statistical analysis, there was a significant difference in the levels of PSA and CA19-9 markers between the two groups (p < 0.001) with those of Ramsar being considerably higher. CEA level did not show any difference. Although some of the volunteers tested positive to the markers, they were in good health as confirmed by the physician. Moreover, the high number of positive markers in Noshahr was considerable. Therefore, future study is needed to further validate this result and to determine the level of positivity to tumor markers in both cities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Evaluation of the Bilio-Pancreatic Region Using Endoscopic Ultrasonography in Patients Referred with and without Abdominal Pain and CA 19-9 Serum Level Elevation

    Directory of Open Access Journals (Sweden)

    Jose Luis Ulla Rocha

    2007-03-01

    Full Text Available Context When assessing the bilio-pancreatic region, collating the findings of serum CA 19- 9 values together with findings from various imaging tests - especially endoscopic ultrasonography - is not a simple issue in daily clinical practice. Objective To assess the usefulness of endoscopic ultrasonography in an Endoscopic Ultrasonography Unit in two situations: patients with asymptomatic elevation of serum CA 19-9 and patients who presented with abdominal pain plus elevation of CA 19-9. Methods A retrospective study of those patients who underwent radial endoscopic ultrasonography between October 2004 and September 2005 in our institution, considering an elevation of CA 19-9 (equal to or greater than 37 U/mL with or without symptoms. In each case, the parameters recorded were: levels of CA 19-9 one week before EUS, results from other imaging techniques (US, helical CT, and final diagnosis according to pathological and/or clinical evolution criteria. Patients with previous attacks of acute pancreatitis and also those who presented with bile duct dilation or space-occupying lesions in image studies (US and CT were excluded. Twenty-two patients met the inclusion criteria. Results Asymptomatic elevation of CA 19-9 was found in 15 patients while 7 patients had elevated CA 19-9 levels as well as pain of uncertain origin. The results of EUS in the asymptomatic patients were: chronic pancreatitis in 7 patients, no pancreatic alterations in 3 patients, and renal cysts, choledocholithiasis, michrolithiasis and liver cirrhosis in one patient, respectively. In patients with abdominal pain, EUS showed chronic pancreatitis in 6 cases and adenocarcinoma of the tail of the pancreas in the remaining patient. Conclusions When EUS was indicated for the asymptomatic elevation of CA 19-9, the main findings were benign diseases. EUS was useful in studying patients with idiopathic abdominal pain and a slight elevation of CA 19-9 since it allowed us to detect chronic

  20. Effect of ultrasound combined with determination of CA19-9 and hs-CRP on the accuracy of early diagnosis of gallbladder cancer

    Directory of Open Access Journals (Sweden)

    Hang-yu ZHANG

    2014-03-01

    Full Text Available Objective  To investigate the value of ultrasound combined with tumor marker CA19-9 and high sensitivity C reactive protein (hs-CRP on the accuracy of early diagnosis of gallbladder cancer. Methods  Ninety-five patients with pathologically confirmed primary gallbladder cancer who received cholecystectomy from Jan. 2008 to Jan. 2013 in our hospital were included in the study. The study also included 51 patients with benign cystic lesions and 51 healthy adults. In all patients, results of pathological examination, B-ultrasound, serum CA19-9 and hs-CRP detection were obtained. In all the healthy adults gallbladder diseases were ruled out, but all of them received serum CA19-9 and hs-CRP determination. Results  Of 95 patients with primary gallbladder cancer, B-ultrasound showed nodules in the gallbladder lumen in 31, tumor mass in 40, and thickened wall in 24. Histological examination showed adenocarcinoma in 87 cases, adenosquamous carcinoma in 6, and squamous carcinoma in 2. There was a statistical difference in hs-CRP and CA19-9 levels between the groups (P<0.05, and the highest level appeared in gallbladder cancer group. There was a high sensitivity but low specificity of CA19-9 or hs-CRP in the diagnosis of primary gallbladder cancer. The sensitivity and specificity were 74.7% and 75.0% when primary gallbladder cancer was diagnosed with B-ultrasound. The positive values of CA19-9 and hs-CRP were ≥100U/ml and ≥6mg/L respectively, when they were combined with B-ultrasound as a single serology factor. When both B-ultrasound and serum levels of CA19-9 and hs-CRP were positive, the diagnostic sensitivity and specificity were 71.6% and 84.4% respectively. When B-ultrasound or serum CA19-9 and hs-CRP were positive, the diagnostic sensitivity and specificity were 98.9% and 66.7% respectively. Conclusions  Combination of B-ultrasound and determination of serum of CA19-9 and hs-CRP can improve the accuracy of the diagnosis of gallbladder

  1. Retrospective Analysis of CA19-9 Decrease in Patients with Metastatic Pancreatic Carcinoma Treated with FOLFIRINOX or Gemcitabine in a Randomized Phase III Study (ACCORD11/PRODIGE4).

    Science.gov (United States)

    Robert, Marie; Jarlier, Marta; Gourgou, Sophie; Desseigne, Françoise; Ychou, Marc; Bouché, Olivier; Juzyna, Beata; Conroy, Thierry; Bennouna, Jaafar

    2017-10-06

    Carbohydrate antigen 19-9 (CA19-9) is a sensitive and specific serum marker in pancreatic cancer. Our retrospective analysis aims to evaluate CA19-9 decrease in patients with metastatic pancreatic cancer treated in ACCORD11/PRODIGE4 (FOLFIRINOX vs. gemcitabine). A total of 342 patients were treated. CA19-9 was measured at 8 weeks (±2) in 160 patients from a total of 282 with abnormal CA19-9 values at baseline (gemcitabine arm, n = 75; FOLFIRINOX arm, n = 85). In the present study, 8-week CA19-9 decrease or greater CA19-9 decrease according to the 20 and 90% thresholds were analyzed. Progression-free survival (PFS) and overall survival (OS) were estimated in each subgroup. In the FOLFIRINOX arm, patients with an 8-week CA19-9 decrease or greater CA19-9 decrease ≥20% showed improved median OS, PFS, and objective response rate. In the overall study population, median OS and PFS were significantly improved in patients with an 8-week CA19-9 decrease ≥20% (vs. decrease was predictive of PFS (interaction test significant according to treatment arm; p = 0.006). An 8-week CA19-9 decrease ≥20% is a prognostic factor for OS and PFS. The 8-week CA19-9 decrease (20% threshold) is predictive of PFS. It could help to evaluate the efficacy of FOLFIRINOX and gemcitabine regimens. © 2017 S. Karger AG, Basel.

  2. Herlyn-Werner-Wunderlich Syndrome: A Rare Cause of Pelvic Pain and High CA 19-9 Levels in an Adolescent Girl

    Science.gov (United States)

    Unal, Emel; Sonmezer, Murat; Erkol, Hatice Gul; Fitoz, Suat

    2016-01-01

    Herlyn-Werner-Wunderlich (HWW) syndrome is a rare developmental anomaly that includes uterus didelphys with obstructed hemivagina and ipsilateral renal agenesis. A 13-year-old girl presented with chronic abdominal pain. Magnetic resonance imaging revealed uterus didelphys, hematometrocolpos and renal agenesis on the right side with imperforate hymen. Subsequently the patient was found to have Mullerian duct anomalies. CA 19-9 level was high. At laparoscopy combined with vaginoscopy hematocolpos was drained following which she improved clinically and CA 19-9 level returned to normal. PMID:26816677

  3. 血清CA15-3、CA50、CA19-9和IL-8检测对女性乳腺癌的诊断价值

    Institute of Scientific and Technical Information of China (English)

    高永旺; 蒋炳辰

    2014-01-01

    Objective:To investigate the clinical signficance of differences on serum CA15-3,CA50,CA19-9,IL-8 levels detection in patients with breast cancer. Methods:Serum CA15-3,CA50,CA19-9,IL-8 concentration from 34 patients (female) with breast cancer and 34 healthy normal controls (female) were determined by RIA and CLIA. Results:The serum CA15-3,CA50,IL-8 levels in patients with breast cancer were significant higher than those in controls. But the serum CA19-9 levels were no significant difference from those in controls.Conclusion:Detection of serum CA15-3,CA50,IL-8 levels might be of prognostic importance in patients with breast cancer.%目的:探讨血清CA15-3、CA50、CA19-9和IL-8检测对乳腺癌患者诊断的临床意义。方法:应用放射免疫法和化学发光法对34例乳腺癌患者(均为女性)进行血清的CA15-3、CA50、CA19-9和IL-8检测,并与34名正常人(均为女性)进行相关对比分析。结果:乳腺癌患者的CA15-3、CA50和IL-8含量水平明显高于对照组(P<0.05),而CA19-9与正常人对照组无明显差异(P>0.05)。结论:血清CA15-3、CA50和IL-8的检测对乳腺癌的发病、预防、诊断和治疗均有重要的临床价值。

  4. Ultrasound-Mediated Microbubble Destruction (UMMD) Facilitates the Delivery of CA19-9 Targeted and Paclitaxel Loaded mPEG-PLGA-PLL Nanoparticles in Pancreatic Cancer.

    Science.gov (United States)

    Xing, Lingxi; Shi, Qiusheng; Zheng, Kailiang; Shen, Ming; Ma, Jing; Li, Fan; Liu, Yang; Lin, Lizhou; Tu, Wenzhi; Duan, Yourong; Du, Lianfang

    2016-01-01

    Pancreatic cancer, one of the most lethal human malignancies with dismal prognosis, is refractory to existing radio-chemotherapeutic treatment modalities. There is a critical unmet need to develop effective approaches, especially for targeted pancreatic cancer drug delivery. Targeted and drug-loaded nanoparticles (NPs) combined with ultrasound-mediated microbubble destruction (UMMD) have been shown to significantly increase the cellular uptake in vitro and drug retention in vivo, suggesting a promising strategy for cancer therapy. In this study, we synthesized pancreatic cancer-targeting organic NPs that were modified with anti CA19-9 antibody and encapsulated paclitaxol (PTX). The three-block copolymer methoxy polyethylene glycol-polylacticco-glycolic acid-polylysine (mPEG-PLGA-PLL) constituted the skeleton of the NPs. We speculated that the PTX-NPs-anti CA19-9 would circulate long-term in vivo, "actively target" pancreatic cancer cells, and sustainably release the loaded PTX while UMMD would "passively target" the irradiated tumor and effectively increase the permeability of cell membrane and capillary gaps. Our results demonstrated that the combination of PTX-NPs-anti CA19-9 with UMMD achieved a low IC50, significant cell cycle arrest, and cell apoptosis in vitro. In mouse pancreatic tumor xenografts, the combined application of PTX-NP-anti CA19-9 NPs with UMMD attained the highest tumor inhibition rate, promoted the pharmacokinetic profile by increasing AUC, t1/2, and mean residence time (MRT), and decreased clearance. Consequently, the survival of the tumor-bearing nude mice was prolonged without obvious toxicity. The dynamic change in cellular uptake, targeted real-time imaging, and the concentration of PTX in the plasma and tumor were all closely associated with the treatment efficacy both in vitro and in vivo. Our study suggests that PTX-NP-anti CA19-9 NPs combined with UMMD is a promising strategy for the treatment of pancreatic cancer.

  5. p53 protein expression and CA19.9 values in differential cytological diagnosis of pancreatic cancer complicated with chronic pancreatitis and chronic pancreatitis

    Institute of Scientific and Technical Information of China (English)

    De-Qing Mu; Guo-Feng Wang; Shu-You Peng

    2003-01-01

    AIM: To evaluate p53 protein overexpression and to measure serum CA19.9 concentrations in cytological diagnosis of patients with suspected pancreatic cancer.METHODS: 24 patients with suspected pancreatic cancer due to chronic pancreatitis, had a pancreatic mass determined by imaging methods. The serum CA19.9 concentration was measured by solid phase radioimmunoassay. On laparotomy,puncture biopsy was performed, and specimens were divided into two parts for cytological diagnosis and detection of p53 protein.RESULTS: Cytology offered a sensitivity of 0.63, a specificity of 1.00, and an accuracy of 0.63. p53 protein analysis offered a sensitivity of 0.44, a specificity of 1.00, and an accuracy of 0.73. CA19.9 offered a sensitivity of 0.44, a specificity of 0.80, and an accuracy of 0.67. The combined cytology and p53 protein analysis showed a sensitivity of 0.78, a specificity of 1.00, and an accuracy of 0.92. Cytology and CA19.9showed a sensitivity of 0.67, a specificity of 0.80, an accuracy of 0.67. combined cytology and p53 protein analysis and CA19.9 showed a sensitivity of 0.78, a specificity of 0.80,and an accuracy of 0.79.CONCLUSION: Superior to any single test, the combined approach is helpful for the differential diagnosis of pancreatic cancer complicated with chronic pancreatitis.The combined cytology and p53 protein analysis offers the best diagnostic efficacy.

  6. Diagnostic Role of F-18 FDG PET/CT in the Follow-up of Patients with Colorectal Cancer: Comparison with Serum CEA, CA 19-9 Levels and Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sung Min; Song, Bong Il; Lee, Hong Je; Seo, Ji Hyoung; Lee, Sang Woo; Yoo, Jeong Soo; Ahn, Byeong Cheol; Lee, Jae Tae; Choi, Kyu Suk; Jun, Soo Han [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2009-04-15

    Early detection of recurrence is an important factor for long term survival of patients with colorectal cancer. Measurement of serum levels of CEA, CA 19-9, CT and PET/CT has been commonly used in the postoperative surveillance of colorectal cancer. The purpose of this study was to compare the diagnostic ability of PET/CT, tumor marker and CT for recurrence in colorectal cancer patients after treatment. F-18 FDG PET/CT imaging was performed in 189 colorectal cancer patients who underwent curative surgical resection and/or chemotherapy. Measurement of serum levels of CEA, CA 19-9 and CT imaging were performed within 2 months of PET/CT examination. Final diagnosis of recurrence was made by biopsy, radiologic studies or clinical follow-up for 6 months after each study. Overall sensitivity, specificity of PET/CT was 94.7%, 91.1%, while those of serum CEA were 44.7% and 97.3%, respectively. Sensitivity and specificity were 94.2%, 90.4% for PET/CT and better than those of combined CEA and CA 19-9 measurement (52.1%, 88.5%) in 174 patients measured available both CEA and CA 19-9 data. In 115 patients with both tumor markers and CT images available, PET/CT showed similar sensitivity but higher specificity (92.9%, 91.3%) compared to combination of tumor markers and CT images (92.9%, 74.1%). PET/CT was superior for detection of recurred colorectal cancer patients compared with both CEA, CA 19-9, and even with combination of both tumor markers and CT. Therefore PET/CT could be used as a routine surveillance examination to detect recurrence or metastasis of colorectal cancer.

  7. Clinical Significance of Measurement the Changes on Serum TGF-α TGF-β1 and CA19-9 Levels Both Before and After Operation in Patients with Primary Liver Cancer%PLC患者手术前后血清TGF-α、TGF-β1和CA19-9检测的临床意义

    Institute of Scientific and Technical Information of China (English)

    伏开新; 姚加平; 刘春燕; 李静

    2013-01-01

    目的:探讨了原发性肝癌(PLC)患者手术治疗前后血清TGF-α、TGF-β1和CA19-9水平的变化及临床意义.方法:应用放射免疫分析对30例PLC患者进行了手术治疗前后血清TGF-α、TGF-β1和CA19-9检测.并与35名正常健康人作比较.结果:PLC患者在手术治疗前血清TGF-α、TGF-β1和CA19-9水平非常显著地高于正常人组(P0.05).结论:检测PLC患者手术治疗前后血清TGF-α、TGF-β1和CA19-9水平的变化在临床上具有重要的价值.

  8. Poussée de maladie de Kaposi et élévation du CA 19-9: penser à la tuberculose!

    Science.gov (United States)

    Ajili, Faida; Hariz, Héla; Souissi, Asmahen; Abid, Rim; Boussetta, Najeh; Laabidi, Besma; Battikh, Riadh; Louzir, Bassem; Othmani, Salah

    2013-01-01

    La maladie de Kaposi (MK) est une entité pathologique qui peut survenir chez les patients VIH positifs et dans le cadre d'une immunodépression, d'origine tuberculeuse très rarement. On décrit le cas d'une MK chez un patient VIH négatif au décours d'une tuberculose. Nous rapportons le cas d'un patient âgé de 81 ans, VIH négatif, ayant présenté deux nodules angiomateux de l'avant bras gauche dont la biopsie cutanée était en faveur d'une MK. L’évolution était marquée 2 mois plus tard, par l'apparition de placards angiomateux extensifs des deux membres supérieurs et d'adénopathies cervicales jugulo-carotidiennes bilatérales. La biopsie ganglionnaire était en faveur d'une tuberculose ganglionnaire. Par ailleurs, il avait un taux sérique élevé des CA 19-9. La régression de l’étendue des lésions au niveau des membres supérieurs et la normalisation du taux sérique des CA 19-9 ont été obtenues sous traitement anti-tuberculeux. Chez les patients atteints d'une MK avec une élévation des CA 19-9, il faut penser à la tuberculose. PMID:24711871

  9. Tissue CA-19.9 content in colorectal adenomas and its value in the assesment of dysplasia Detección de CA-19.9 citosólico en adenomas colorrectales: Utilidad en el diagnóstico de la displasia

    Directory of Open Access Journals (Sweden)

    I. Salces

    2004-04-01

    Full Text Available Background: occasionally, the risk of malignant transformation may be difficult to establish in adenomatous polyps due to the fact that they contain areas with variable grades of dysplasia. A measurement of tissue tumor markers may be useful to recognize these adenomas. Objectives: the aims of this study were: to establish firstly the relationship between carbohydrate antigen 19.9 (CA-19.9 content in the colorectal mucosa and the characteristics of polyps, and secondly, the diagnostic value of the former's measurement. Patients and methods: tissue CA-19.9 concentration was measured in 155 colorectal samples obtained from 145 patients (21 normal mucosa; 113 adenomatous polyps; 21 adenocarcinoma. Cytosol CA-19.9 content was determined by enzyme-linked immunoadsorbant assay, and the measurement of this protein was achieved by quantitative assay. Tissue samples were also processed for histological examination. Results: we demonstrated that CA-19.9 levels in adenomatous polyps and adenocarcinomas were significantly higher than in the normal mucosa. These levels varied significantly according to polyp size, histological type, and grade of dysplasia. CA-19.9 contents were higher in polyps with a high risk of malignant transformation than in those with a low risk of severe dysplasia. The cut-off value 214 U/mg of protein properly differentiated both types of risk. The area under the receiver operating characteristic (ROC curves showed that cytosol CA-19.9 levels allow classifying polyps according to their histological features. Conclusions: we concluded that the measurement of CA-19.9 content in adenomatous polyps may be useful to classify these tumors and confirm the feasibility to separate adenomas into two groups: low and high risk of malignant change.Introducción: en ocasiones, el riesgo de transformación maligna de los pólipos adenomatosos es difícil de identificar por existir zonas con distintos grados de displasia simultáneamente. La

  10. Site-specifically labeled CA19.9-targeted immunoconjugates for the PET, NIRF, and multimodal PET/NIRF imaging of pancreatic cancer

    Science.gov (United States)

    Houghton, Jacob L.; Zeglis, Brian M.; Abdel-Atti, Dalya; Aggeler, Robert; Sawada, Ritsuko; Agnew, Brian J.; Scholz, Wolfgang W.; Lewis, Jason S.

    2015-01-01

    Molecular imaging agents for preoperative positron emission tomography (PET) and near-infrared fluorescent (NIRF)-guided delineation of surgical margins could greatly enhance the diagnosis, staging, and resection of pancreatic cancer. PET and NIRF optical imaging offer complementary clinical applications, enabling the noninvasive whole-body imaging to localize disease and identification of tumor margins during surgery, respectively. We report the development of PET, NIRF, and dual-modal (PET/NIRF) imaging agents, using 5B1, a fully human monoclonal antibody that targets CA19.9, a well-established pancreatic cancer biomarker. Desferrioxamine (DFO) and/or a NIRF dye (FL) were conjugated to the heavy-chain glycans of 5B1, using a robust and reproducible site-specific (ss) labeling methodology to generate three constructs (ssDFO-5B1, ssFL-5B1, and ssdual-5B1) in which the immunoreactivity was not affected by the conjugation of either label. Each construct was evaluated in a s.c. xenograft model, using CA19.9-positive (BxPC3) and -negative (MIAPaCa-2) human pancreatic cancer cell lines. Each construct showed exceptional uptake and contrast in antigen-positive tumors with negligible nonspecific uptake in antigen-negative tumors. Additionally, the dual-modal construct was evaluated in an orthotopic murine pancreatic cancer model, using the human pancreatic cancer cell line, Suit-2. The ssdual-5B1 demonstrated a remarkable capacity to delineate metastases and to map the sentinel lymph nodes via tandem PET-computed tomography (PET/CT) and NIRF imaging. Fluorescence microscopy, histopathology, and autoradiography were performed on representative sections of excised tumors to visualize the distribution of the constructs within the tumors. These imaging tools have tremendous potential for further preclinical research and for clinical translation. PMID:26668398

  11. Evaluation of SIMA, CEA, CA50 and CA19 - 9 in 56 cases of advanced gastric carcinoma%56例进展期胃癌胃者SIMA、CEA、CA50、CA19-9联合检测评价

    Institute of Scientific and Technical Information of China (English)

    陈宜刚; 叶军

    2001-01-01

    目的对56例进展期胃癌患者进行4种血清肿瘤标记物联合检测评价,探索优选检测项目,提高诊断的灵敏度、准确性.方法应用酶免双抗夹心法测定SIMA和应用放射免疫方法测定CEA、CA50、CA19-9,共测定正常对照组33例健康成人和进展期胃癌56例.结果胃癌组4种血清肿瘤标记物均与正常对照组差异有显著性意义(P<0.05),其中正常对照组SIMA为(8.09±1.94)×103u/L,胃癌组SIMA为(90.47±28.51)×103u/L.SIMA的灵敏度和准确性高于其它3种,与CEA灵敏度相比,差异无显著意义(P>0.05),SIMA与CEA组合灵敏度升高至81.76%,高于单项灵敏度,高于其它组合灵敏度,差异有显著意义(P<0.05).结论SIMA是一种敏感的新型血清肿瘤标记物,SIMA和CEA可以作为联合检测胃癌的首选标志.

  12. 56例进展期胃癌患者SIMA、CEA、CA50、CA19-9联合检测评价%Evaluation of SIMA, CEA, CA50 and CA19-9 in 56 Cases of Advanced Gastric Carcinoma

    Institute of Scientific and Technical Information of China (English)

    陈宜刚; 叶军

    2001-01-01

    目的对56例进展期胃癌患者进行4种血清肿瘤标记物联合检测评价,探索优选检测项目,提高诊断的灵敏度、准确性.方法应用酶免双抗夹心法测定SIMA和应用放射免疫方法测定CEA、CA50、CA19-9,共测定正常对照组33例健康成人和进展期胃癌56例.结果胃癌组4种血清肿瘤标记物均与正常对照组差异有显著性意义(p<0.05),其中正常对照组SIMA为(8.09±1.94)×103u/L,胃癌组SIMA为(90.47±28.51)×103u/L.SIMA的灵敏度和准确性高于其它3种,与CEA灵敏度相比,差异无显著意义(p>0.05),SIMA与CEA组合灵敏度升高至81.76%,高于单项灵敏度,高于其它组合灵敏度,差异有显著意义(p<0.05).结论SIMA是一种敏感的新型血清肿瘤标记物,SIMA和CEA可以作为联合检测胃癌的首选标志.

  13. Evaluation of SIMA,CEA,CA50 and CA19-9 in 56 cases of advanced gastric carcinoma%56例进展期胃癌患者SIMA、CEA、CA50、CA19-9联合检测评价

    Institute of Scientific and Technical Information of China (English)

    陈宜刚; 叶军

    2002-01-01

    目的:对56例进展期胃癌患者进行4种血清肿瘤标记物联合检测评价,探索优选检测项目,提高诊断的灵敏度、准确性.方法:应用酶免双抗夹心法测定SIMA和应用放射免疫方法测定CEA、CA50、CA19-9,共测定正常对照组33例健康成人和进展期胃癌56例.结果:胃癌组4种血清肿肿瘤标记物均与正常对照组差异有显著性意义(P<0.05),其中正常对照组SIMA为(8.09±1.94)×103u/L,胃癌组SIMA为(90.47±28.51)×103u/L.SIMA的灵敏度和准确性高于其它3种,与CEA灵敏度相比,差异无显著意义(P>0.05),SIMA与CEA组合灵敏度升高至81.76%,高于单项灵敏度,高于其它组合灵敏度,差异有显著意义(P<0.05).结论:SIMA是一种敏感的新型血清肿瘤标记物,SIMA和CEA可以作为联合检测胃癌的首选标志.

  14. CA19-9 decrease at 8 weeks as a predictor of overall survival in a randomized phase III trial (MPACT) of weekly nab-paclitaxel plus gemcitabine versus gemcitabine alone in patients with metastatic pancreatic cancer.

    Science.gov (United States)

    Chiorean, E G; Von Hoff, D D; Reni, M; Arena, F P; Infante, J R; Bathini, V G; Wood, T E; Mainwaring, P N; Muldoon, R T; Clingan, P R; Kunzmann, V; Ramanathan, R K; Tabernero, J; Goldstein, D; McGovern, D; Lu, B; Ko, A

    2016-04-01

    A phase I/II study and subsequent phase III study (MPACT) reported significant correlations between CA19-9 decreases and prolonged overall survival (OS) with nab-paclitaxel plus gemcitabine (nab-P + Gem) treatment for metastatic pancreatic cancer (MPC). CA19-9 changes at week 8 and potential associations with efficacy were investigated as part of an exploratory analysis in the MPACT trial. Untreated patients with MPC (N = 861) received nab-P + Gem or Gem alone. CA19-9 was evaluated at baseline and every 8 weeks. Patients with baseline and week-8 CA19-9 measurements were analyzed (nab-P + Gem: 252; Gem: 202). In an analysis pooling the treatments, patients with any CA19-9 decline (80%) versus those without (20%) had improved OS (median 11.1 versus 8.0 months; P = 0.005). In the nab-P + Gem arm, patients with (n = 206) versus without (n = 46) any CA19-9 decrease at week 8 had a confirmed overall response rate (ORR) of 40% versus 13%, and a median OS of 13.2 versus 8.3 months (P = 0.001), respectively. In the Gem-alone arm, patients with (n = 159) versus without (n = 43) CA19-9 decrease at week 8 had a confirmed ORR of 15% versus 5%, and a median OS of 9.4 versus 7.1 months (P = 0.404), respectively. In the nab-P + Gem and Gem-alone arms, by week 8, 16% (40/252) and 6% (13/202) of patients, respectively, had an unconfirmed radiologic response (median OS 13.7 and 14.7 months, respectively), and 79% and 84% of patients, respectively, had stable disease (SD) (median OS 11.1 and 9 months, respectively). Patients with SD and any CA19-9 decrease (158/199 and 133/170) had a median OS of 13.2 and 9.4 months, respectively. This analysis demonstrated that, in patients with MPC, any CA19-9 decrease at week 8 can be an early marker for chemotherapy efficacy, including in those patients with SD. CA19-9 decrease identified more patients with survival benefit than radiologic response by week 8. © The Author 2016. Published by Oxford University Press on behalf of the European

  15. 肾盂尿路上皮癌患者尿 NMP22、TPS、CYFRA21-1、CA19-9的检测与评估%Evaluation of NMP22,TPS,CYFRA21-1 and CA19-9 in the urine of patients for the diagnosis of urothelial carcinoma of renal pelvis

    Institute of Scientific and Technical Information of China (English)

    李志斌; 陈惠庆; 米振国; 宋继文; 韩雪冰; 韩存芝

    2016-01-01

    目的探讨尿液核基质蛋白22(nuclear matrix protein 22,NMP22)、组织多肽特异性抗原(tissue polypeptide-specific antigen,TPS)、CYFRA21-1、糖链蛋白19-9(carbohydrate antigen 19-9,CA19-9)对肾盂尿路上皮癌的诊断价值.方法回顾性分析山西省肿瘤医院2010年1月至2015年12月检测的至少两种上述尿液肿瘤标志物的患者资料,共218人次,包括肾盂尿路上皮癌63例(A 组)、膀胱尿路上皮癌46例(B 组)、非尿路上皮肿瘤的泌尿系其他疾病62例(C 组)、A组行根治术后2年未复发47例(D 组),另有健康志愿者20例(E 组).比较各组尿 NMP22、TPS、CYFRA21-1、CA19-9表达水平,并绘制受试者工作特征(receiver operating characteristic,ROC)曲线,计算 ROC 曲线下面积.结果 A 组 NMP22水平高于 B 组,差异有统计学意义(P =0.001). A 组与 B 组的 TPS、CYFRA21-1、CA19-9水平差异无统计学意义(P >0.05).A 组和 B 组的 TPS、NMP22、CYFRA21-1、CA19-9水平均高于 C 组、D 组、E 组,差异有统计学意义(P <0•05).C 组、D组及 E 组的 NMP22、TPS、CYFRA21-1、CA19-9水平差异无统计学意义(P >0.05). A 组中NMP22、TPS、CYFRA21-1、CA19-9水平在不同病理分级、临床分期、肿瘤大小、是否肾积水等的差异无统计学意义(P >0.05).A 组 NMP22、TPS、CYFRA21-1、CA19-9的诊断准确率高于尿脱落细胞学检查,差异有统计学意义(P <0.05).四种肿瘤标志物的 ROC 曲线下面积为0.7~0.9,诊断效能中等,最高者为 NMP22与 CYFRA21-1的组合,为0.884.结论尿液 NMP22、TPS、CYFRA21-1、CA19-9对肾盂尿路上皮癌的诊断有帮助,诊断效能中等,但它们对肾盂癌肿瘤分期和病理分级的预测、术后监测、预后判断等方面的作用有待进一步研究.%Objective To study the diagonsis value of urinary tissue polypeptide-specific anti-gen (TPS),nuclear matrix protein 22 (NMP22 ),CYFRA21-1 and carbohydrate antigen 1 9-9 (CA1 9-9)in

  16. Decreased serum CA19-9 is associated with improvement of insulin resistance and metabolic control in patients with obesity and type 2 diabetes after Roux-en-Y gastric bypass

    Science.gov (United States)

    Tu, Yinfang; Yu, Haoyong; Zhang, Pin; Di, Jianzhong; Han, Xiaodong; Wu, Songhua; Bao, Yuqian; Jia, Weiping

    2014-01-01

    Aims/Introduction Patients with type 2 diabetes are known to show elevated serum levels of carbohydrate antigen 19-9 (CA19-9). The aim of the present study was to investigate the possible relationships of CA19-9 with metabolic control, insulin resistance (IR), and pancreatic β-cell function in patients with obesity and type 2 diabetes who underwent Roux-En-Y gastric bypass (RYGB). Materials and Methods The present study included 81 healthy volunteers, and 33 patients diagnosed with obesity and type 2 diabetes who underwent RYGB. Anthropometry, serum levels of CA19-9, glucose and lipid metabolic profiles, and serum insulin levels were determined at baseline and at 12 weeks after RYGB. Results Changes in CA19-9 were significantly and positively correlated with changes in fasting plasma glucose (r = 0.552, P = 0.001), 2-h post-challenge plasma glucose levels (r = 0.623, P = 0.000), glycated hemoglobin levels (r = 0.819, P = 0.000), glycated albumin levels (r = 0.711, P = 0.000), total cholesterol (r = 0.449, P = 0.009) and the Homeostasis Model of Assessment-IR index (r = 0.407, P = 0.019). Furthermore, a multiple stepwise regression analysis showed that the changes in serum levels of CA19-9 were independently and significantly associated with changes in glycated hemoglobin (β = 0.598, P = 0.000), fasting plasma glucose (β = 0.309, P = 0.000) and Homeostasis Model of Assessment-IR (β = 0.235, P = 0.010) after adjusting for confounding factors. Conclusions CA19-9 could be an effective indicator of IR, and glycemic and lipid metabolism in patients with obesity and type 2 diabetes after rapid metabolic control by RYGB. Additionally, CA19-9 might be a marker with which to evaluate the short-term effects of glycolipid toxicity on IR in these patients. PMID:25422770

  17. Diagnostic value of joint detection of serum CA1 9-9,CA125 and CA242 for cholangiocarci-noma%血清 CA 19-9CA 125、CA242联合检测对胆管癌诊断价值的评价

    Institute of Scientific and Technical Information of China (English)

    崔大鹏; 韩磊; 刘振显; 杨贺; 张迎春

    2016-01-01

    Objective:To study the diagnostic value of joint detection of serum CA1 9-9,CA125 and CA242 for cholan-giocarcinoma.Methods:A total of 35 patients with cholangiocarcinoma who received surgical resection in our hospital were se-lected as malignant group;30 patients with cholelithiasis who received surgical resection in our hospital during the same period were selected as benign group.Serum samples were collected before surgery to determine CA1 9-9,CA125 and CA242 content;and cholangiocarcinoma tissue and normal bile duct tissue were collected after surgery to determine the content of proliferation and invasion molecules.Results:Serum CA1 9-9,CA125 and CA242 levels of malignant group were significantly higher than those of control group (P <0.05);PROX-1,Ki-67,Bcl-2,Bad,Gab1,LOXL2,TRPM7 and CXCL12 levels in cholangiocar-cinoma tissue were significantly higher than those in benign bile duct tissue (P <0.05);and E-cadherin level was significantly lower than that in benign bile duct tissue (P <0.05);serum CA1 9-9,CA125 and CA242 levels were positively correlated with PROX-1,Ki-67,Bcl-2,Bad,Gab1,LOXL2,TRPM7 and CXCL12 levels,and negatively correlated with E-cadherin level. Conclusions:Joint detection of serum CA1 9-9,CA125 and CA242 can not only provide reference for the diagnosis of cholangio-carcinoma,but also can provide basis for the evaluation of proliferation,invasion and other malignant biological behaviors.%目的::研究血清 CA19-9CA125、CA242联合检测对胆管癌的诊断价值.方法:选择在我院接受手术切除的35例胆管癌患者作为恶性组,同期在我院接受手术切除的30例胆石症患者作为良性组,术前采集血清标本并测定 CA19-9CA125、CA242含量,术后采集胆管癌组织和正常胆管组织并测定增殖、侵袭分子的含量.结果:恶性组血清中 CA19-9CA125、CA242的含量显著高于对照组(P <0.05);胆管癌组织中 PROX-1、Ki-67、Bcl-2、Bad、Gab1、LOXL2、TRPM7、CXCL12

  18. Ultrasensitive photoelectrochemical immunoassay for CA19-9 detection based on CdSe@ZnS quantum dots sensitized TiO2NWs/Au hybrid structure amplified by quenching effect of Ab2@V(2+) conjugates.

    Science.gov (United States)

    Zhu, Hua; Fan, Gao-Chao; Abdel-Halim, E S; Zhang, Jian-Rong; Zhu, Jun-Jie

    2016-03-15

    A novel, enhanced photoelectrochemical immunoassay was established for sensitive and specific detection of carbohydrate antigen 19-9 (CA19-9, Ag). In this protocol, TiO2 nanowires (TiO2NWs) were first decorated with Au nanoparticles to form TiO2NWs/Au hybrid structure, and then coated with CdSe@ZnS quantum dots (QDs) via the layer-by-layer method, producing TiO2NWs/Au/CdSe@ZnS sensitized structure, which was employed as the photoelectrochemical matrix to immobilize capture CA19-9 antibodies (Ab1); whereas, bipyridinium (V(2+)) molecules were labeled on signal CA19-9 antibodies (Ab2) to form Ab2@V(2+) conjugates, which were used as signal amplification elements. The TiO2NWs/Au/CdSe@ZnS sensitized structure could adequately absorb light energy and dramatically depress electron-hole recombination, resulting in evidently enhanced photocurrent intensity of the immunosensing electrode. While target Ag were detected, the Ab2@V(2+) conjugates could significantly decrease the photocurrent detection signal because of strong electron-withdrawing property of V(2+) coupled with evident steric hindrance of Ab2. Thanks to synergy effect of TiO2NWs/Au/CdSe@ZnS sensitized structure and quenching effect of Ab2@V(2+) conjugates, the well-established photoelectrochemical immunoassay exhibited a low detection limit of 0.0039 U/mL with a wide linear range from 0.01 U/mL to 200 U/mL for target Ag detection. This proposed photoelectrochemical protocol also showed good reproducibility, specificity and stability, and might be applied to detect other important biomarkers.

  19. Carbohydrate 19.9 Antigen Serum Levels in Liver Disease

    Directory of Open Access Journals (Sweden)

    Gaetano Bertino

    2013-01-01

    Full Text Available Background. Carbohydrate 19.9 antigen (CA19.9 has been used in the diagnosis and followup of gastrointestinal tumours. The aim of this prospective longitudinal study was the evaluation of CA19.9 levels in patients with chronic hepatitis and hepatic cirrhosis hepatitis C virus and B virus correlated. Materials and Methods. 180 patients were enrolled, 116 with HCV-related chronic liver disease (48% chronic hepatitis, 52% cirrhosis and 64 with HBV-related chronic liver disease (86% chronic hepatitis, 14% cirrhosis. Patients with high levels of CA19.9 underwent abdominal ecography, gastroendoscopy, colonoscopy, and abdominal CT scan. Results. 51.7% of patients with HCV-related chronic liver disease and 48.4% of those with HBV-related chronic liver disease presented high levels of CA19.9. None was affected by pancreatic or intestinal neoplasia, cholestatic jaundice, or other diseases potentially able to induce Ca19.9 elevations. CA19.9 levels were elevated in 43.3% of HCV chronic hepatitis, in 56.3% of HCV cirrhosis, in 45.1% of HBV chronic hepatitis, and in 58% of HBV cirrhosis. Conclusions. CA19.9 commonly increases in the serum of patients with chronic viral hepatitis. Elevation of CA 19.9 is not specific for neoplastic disease and is related to the severity of fibrosis and to the viral aetiology of hepatitis.

  20. CEA和CA19-9联合检测在直肠癌诊断及疗效评估中的应用价值%The value of CEA and CA19-9 in rectal cancer diagnosis and therapeutic effect evaluation

    Institute of Scientific and Technical Information of China (English)

    张静

    2016-01-01

    目的:研究癌胚抗原(carcino-embryonic antigen, CEA)和糖链抗原19-9(carbohydrate antigen 19-9, CA19-9)联合检测在直肠癌诊断及疗效评估中的应用价值。方法选择2011年5月至2015年5月我院60例直肠癌患者作为观察组,选择70例同期来我院健康体检者作为对照组。采用电化学发光法检测两组研究对象CEA和CA19-9水平,对检测结果进行统计学分析。结果观察组CEA和CA19-9检测结果均显著高于对照组,且差异均有统计学意义(P均<0.05);CA19-9单独检测诊断直肠癌的灵敏度、特异性及准确度均高于CEA;CEA和CA19-9联合检测诊断直肠癌的灵敏度、特异性及准确度均高于二者单独检测;随疾病疗效的恶化,CEA及CA19-9的检测水平均呈上升趋势,不同疗效患者CEA和CA19-9水平比较,差异均有统计学意义(P均<0.05),且组间两两比较,差异均有统计学意义(P均<0.05)。结论 CEA联合CA19-9能显著提高直肠癌检出率,对评估直肠癌放化疗疗效具有较高临床应用价值。%Objective To research the value of carcino-embryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) in rectal cancer diagnosis and therapeutic effect evaluation. Methods 60 cases pa-tients with rectal cancer from May 2011 to May 2015 in our hospital were collected as observation group , and 70 cases healthy people at the same periods were collected as control group. The CEA and CA19-9 levels of all the subjects were detected by electrochemiluminescence method , and the results were analyzed statistically. Results The CEA and CA19-9 levels in observation group were all higher than that of control group , and the differences all had statistical significance (Pall<0.05). The sensitivity, specificity, and accuracy of CA19-9 were all higher than that of CEA in rectal cancer diagnosis. The sensitivity, specificity, and accuracy of CEA and CA19-9

  1. An immunohistochemical study of primary signet-ring cell carcinoma of the stomach and colorectum: III. Expressions of EMA, CEA, CA19-9, CDX-2, p53, Ki-67 antigen, TTF-1, vimentin, and p63 in normal mucosa and in 42 cases.

    Science.gov (United States)

    Terada, Tadashi

    2013-01-01

    There have no comprehensive immunohistochemical studies of primary signet ring cell carcinoma (SRCC) in the stomach and colorectum. The author examined the expression of nine common antigens (EMA, CEA, CA19-9, CDX-2, p53, Ki-67 antigen, TTF-1, vimentin, and p63) in the non-tumorous normal epithelium of the stomach and colorectum and in 42 cases of primary SRCC of the stomach (30 cases) and colorectum (12 cases). The normal epithelium of the stomach and colon consistently (100%) expressed EMA, CEA, CA19-9, CDX-2, and Ki-67 (labeling gastric SRCC, the expression percentage of EMA was 57% (17/30), CEA 100% (30/30), CA19-9 100% (30/30), CDX-2 43% (13/30), p53 83% (25/30), Ki-67 100% (30/30) (labeling index= 36 ± 23 %), TTF-1 0% (0/30), vimentin 0% (0/30), and p63 0% (0/30). In primary colorectal SRCC, the expression percentage of EMA was 25% (3/12), CEA 100% (12/12), CA19-9 100% (12/12), CDX-2 93% (28/30), p53 75% (9/12), Ki-67 100% (30/30) (labeling index= 47% ± 26 %), TTF-1 0% (0/12), vimentin 0% (0/12), and p63 0% (0/12). A comparative statistical analysis showed significant difference in EMA (gastric SRCC 57% vs colorectal SRCC 25%) and CDX-2 (43% vs 93%). There were no significant differences in the other seven antigens' expression between primary gastric SRCC and primary colorectal SRCC. These findings provide much knowledge of primary SRCC of the stomach and colorectum. The data indicated primary gastric SRCC frequently express EMA but not CDX-2 whereas primary colorectal SRCC frequently express CDX-2 but not EMA. These findings also suggest that EMA and CDX-2 are down-regulated during the gastric SRCC carcinogenesis. This down regulations may be associated with the malignant transformation of gastric SRCC. The data of colorectal SRCC suggest EMA is markedly down-regulated and also suggest that this EMA down-regulation may be associated with the carcinogenesis of colorectal SRCC. The expression pattern of EMA and CDX-2 may be useful in differential diagnosis

  2. 肝病患者肿瘤标记物CA19-9CA125协同升高对重度肝纤维化具有高度特异性

    Institute of Scientific and Technical Information of China (English)

    Schoniger-Hekele; M.; Müller; C.

    2006-01-01

    肝硬化时肿瘤标记物的升高往往是非特异性的,目前尚无将其应用于鉴别肝纤维化程度的相关报道。该文旨在探讨肿瘤标记物是否能用于预测重度肝纤维化。研究选取125例接受过肝活检的酒精性肝炎、乙型肝炎或丙型肝炎患者,采用常规的实验室方法检测其肿瘤标记物CA19—9、CA15—3、CA125水平,并分析其与肝纤维化程度之间的相关性。其中,肝纤维化1~2级被定义为轻度纤维化,而3~4级则定义为重度纤维化。研究表明,肿瘤标记物CA19—9、CA15—3、CA125的水平随肝纤维化的程度而升高。应用于鉴别轻度(F1+F2)或重度肝纤维化(F3+F4)时,CA19—9、CA125、CA15—3的敏感度与特异度分别为70.5%、38.1%、19.0%与88.6%、89.7%、93.0%。CA19—9和CA125联合评分的logistic回归分析表明,CA19—9/CA125评分每升高1分,重度肝纤维化的可能性就增加1。6倍。与目前广泛应用的肝硬化Bonacini判断评分相比,CA19—9/CA125评分有相似特异度(97.1%vs100%),而敏感度更高(42.9%vs33.3%)。CA19—9与CA125的协同升高由:于二检测相对简便,因此除了可获得相似的特异度(98.5%)之外,亦能达到最佳的阳性预测值(92.9%),

  3. 30 CFR 19.9 - Performance.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Performance. 19.9 Section 19.9 Mineral... MINING PRODUCTS ELECTRIC CAP LAMPS § 19.9 Performance. In addition to the general design and the safety... respect to performance, as follows: (a) Time of burning and candlepower. Permissible electric cap...

  4. 22 CFR 19.9-1 - Entitlement.

    Science.gov (United States)

    2010-04-01

    ...) A pension benefit under this section is treated the same as a survivor annuity for purposes of § 19... to a monthly pension benefit effective on a date determined under § 19.9-2 in an amount determined under § 19.9-3. (b) A former spouse shall not be qualified for a pension under this subsection...

  5. CK19mRNA、CEA 和 CA199对结直肠癌预后判断的价值及在随诊中的意义%The Value of Prognosis and Significance of follow up in Colorectal Cancer Patients of Peripheral Blood CK19mRNA、CEA、CA19-9

    Institute of Scientific and Technical Information of China (English)

    高继绪

    2013-01-01

    目的:探讨 CK19mRNA、CEA 和 CA199对结直肠癌预后判断的价值及在随诊中的意义。方法:收集76例结直肠癌患者、35例结直肠良性疾病患者和20例健康献血员的外周血细胞,分别抽提 RNA,逆转录聚合酶链反应法测定 CK19mRNA 水平;收集上述病例外周血血浆,电化学发光法检测 CEA,CA199含量。数据分别以 t 检验和 x2检验进行统计学处理。结果:三联检测的灵敏度、约登指数最高。结论:结直肠癌患者外周血 CK19mRNA、CEA、CA199联合检测可起到互补作用,明显提高检测的灵敏度和约登指数,能较好的提高大肠癌患者的阳性率,帮助临床大夫选择合理的治疗方案,综合判断预后,在随诊中及早发现复发。%Objective:To explore the value of prognosis and significance of fol ow up in colorectal cancer patients of peripheral blood CK19mRNA、CEA、CA19-9.Methods:With the application of reverse transcription polymerase chain reaction(RT-PCR)and ECLIA,test the level of peripheral blood CK19mRNA、CEA、CA19-9,Do testing for 76cases of colorectal cancer patients, 35 cases of benign lung diseases patients and 20 health blood donors.For data statistics, apply t-test and x2-test. Results :The joint detection sensitivity, about the highest .Conclusion:The joint detection of colorectal cancer patients of peripheral blood CK19mRNA,CEA,CA19-9 can play a complementary role and notably promote the sensitivity and youden index of peripheral blood testing, but specificity with no significant decline.The joint detection has important clinical significance in prognosis, treatment and recurrence of colorectal cancer.

  6. Acute Cholecystitis with Significantly Elevated Levels of Serum Carbohydrate Antigen 19-9

    Directory of Open Access Journals (Sweden)

    Shuji Akimoto

    2016-08-01

    Full Text Available Serum carbohydrate antigen 19-9 (CA 19-9, a marker of malignant tumors, is generally slightly elevated in benign conditions. We report a case of acute cholecystitis with a significantly elevated level of serum CA 19-9 based on positron emission tomography (PET-computed tomography (CT findings. A 65-year-old woman presented with abdominal pain and fever. A CT image revealed an enlarged gallbladder without tumor shadows. The C-reactive protein (CRP level was elevated to 7.66 mg/dl. Moreover, the serum CA 19-9 level was significantly elevated to 19,392 U/ml. We started antibiotic treatment, because we suspected acute cholecystitis, but still, we could not ignore the possible presence of malignant tumors. After 11 days of antibiotic treatment, serum CRP and CA 19-9 levels decreased to 0.11 mg/dl and 1,049 U/ml, respectively. There was an accumulation of fluorine 18-labeled fluorodeoxyglucose (maximum standardized uptake value, 9.3 without tumor shadows in the liver, near the gallbladder, on the PET-CT examination. We considered the possibility that the inflammation had spread from the gallbladder to the liver, made a diagnosis of acute cholecystitis, and performed a cholecystectomy 33 days after treatment initiation. The serum CA 19-9 level decreased to 45 U/ml after the surgery. One year after the surgery, the patient was alive, and the serum CA 19-9 level was 34 U/ml. Acute cholecystitis with a significantly high elevation of the serum CA 19-9 level is rare. In such cases, it is important to confirm the change in the serum CA 19-9 level over time after antibiotic treatment and perform imaging studies to distinguish between inflammation and malignancy.

  7. Dynamic change of 19-9 in bile duct cancer tumor markers of serum carbohydrate antigen and its clinical significance%胆管癌患者血清肿瘤标志物糖类抗原19-9的动态变化及其临床意义

    Institute of Scientific and Technical Information of China (English)

    韩笑; 麻树人; 杨卓; 宫照杰; 傅赞

    2013-01-01

    目的 探讨胆管癌患者的血清肿瘤标志物糖类抗原(CA)19-9的变化情况,并评价其在临床中的意义.方法 采取化学发光免疫法对沈阳军区总医院2010年1月~2010年12月收治的50例胆管癌患者(研究组)和同期的50例胆道良性疾病患者(对照1组)以及50名健康对象(对照2组)血清中CA19-9含量进行测定.结果 通过三组的对比分析,研究组患者的CA19-9含量为(288.6±45.6)U/mL,对照1组的CA19-9含量为(92.3±12.4)U/mL,对照2组CA19-9含量为(17.4±5.6)U/mL,研究组患者的CA19-9含量明显高于对照1组和对照2组的CA19-9含量,三组数据比较差异有统计学有意义(P<0.05);胆管癌Ⅰ期患者CA19-9含量为(118.6±47.5) U/mL,Ⅱ~Ⅲ期患者CA19-9含量为(222.3±54.4)U/mL,Ⅳ期患者CA19-9含量为(452.4±55.6)U/mL,三组数据比较差异有统计学有意义(P<0.05).结论 临床中对于测定CA19-9能够对胆管癌患者的筛查和临床分期具有一定的诊断效果,而且可以依据不同的含量情况进行判断临床分期情况,在临床中具有较好的应用价值.%Objective To investigate the changes of cholangiocarcinoma in patients with serum tumor markers carbohydrate antigen 19-9,and to evaluate its clinical significance.Methods A chemiluminescent immunoassay the same period in our hospital from January 2010 to December 2010 were treated 50 cases of cholangiocarcinoma patients (study group) and 50 cases of benign biliary diseases (control group 1) and 50 healthy subjects (control group 2) serum carbohydrate antigen 19-9 were determined.Results A comparative analysis of three groups,CA19-9 levels in the patients of the study group of (288.6±45.6) U/mL,control group 1 CA19-9 levels of (92.3 ± 12.4) U/mL,control group 2 CA19-9 content of (17.4±5.6) U/mL,content of CA19-9 in patients of the study group of CA19-9 was significantly higher than the control group 1 and control group 2,three sets of data compared with a significant difference

  8. 22 CFR 19.9 - Pension benefits for former spouses.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Pension benefits for former spouses. 19.9 Section 19.9 Foreign Relations DEPARTMENT OF STATE PERSONNEL BENEFITS FOR SPOUSES AND FORMER SPOUSES OF PARTICIPANTS IN THE FOREIGN SERVICE RETIREMENT AND DISABILITY SYSTEM § 19.9 Pension benefits for former spouses....

  9. Association between carcinoembryonic antigen, carbohydrate antigen 19-9 and body mass index in colorectal cancer patients.

    Science.gov (United States)

    Chen, Wei; Liu, Qin; Tan, Shu-Yun; Jiang, Yan-Hui

    2013-09-01

    Carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) have been well recognized as tumor markers for colorectal cancer. Previous studies suggested that obesity is inversely associated with the screening of CEA and CA19-9 levels and may reduce screening sensitivity. This study was conducted to evaluate the association of body mass index (BMI) with serum CEA and CA19-9 concentration in colorectal cancer patients. A total of 300 patients were enrolled in the study, selected from 2,950 consecutive colorectal cancer patients who underwent surgical treatment between August, 1994 and December, 2005. The association of BMI with CEA concentration, total circulating CEA mass and plasma volume was assessed by determining P-values for trends. The multivariate linear regression analysis was used to adjust for clinicopathological confounding factors to analyze the main outcome measures when CEA and CA19-9 had been log-transformed. Increased BMI was linearly correlated with a higher plasma volume. Using the stepwise method, the multiple regression model including BMI categories was reconstructed as follows: loge[CEA]=0.208+0.241[liver metastasis]+0.051 [differentiation]+0.092[TNM]; loge[CA19-9]=0.969+0.233 [gender]+0.141[ascites]+0.09[TNM]. The mean survival time in CEA(+)/CA19-9(-), CEA(+)/CA19-9(+), CEA(-)/CA19-9(-) and CEA(-)/CA19-9(+) patients was 84.8, 58.2, 100.6 and 74.7 months, respectively. The 1-/3-year survival rates in each group was 76.0/59.8, 66.2/43.5, 96.3/87.6 and 71.7/41.0, respectively. In conclusion, the decreased concentration of CEA and CA19-9 in patients of higher BMIs may be the result of the hemodilution effect. The BMI factor should be considered during the surveillance of colorectal cancer. In addition, patients with simultaneous positive expression of CEA and CA19-9 exhibited shorter survival time.

  10. 38 CFR 19.9 - Remand for further development.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Remand for further development. 19.9 Section 19.9 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS....9 Remand for further development. (a) General. If further evidence, clarification of the...

  11. Persistent High Level of Urinary Tumor Marker Carbohydrate Antigen 19-9 in Prenatally Diagnosed Dysplastic Kidney

    Directory of Open Access Journals (Sweden)

    Reza Khorramirouz

    2014-01-01

    Full Text Available Tumor marker carbohydrate antigen 19-9 (CA 19-9 level has gained clinical significance in gastrointestinal malignancies and in various solid and cystic diseases. Dysplastic kidney is a congenital abnormality resulting from atresia of the ureteral bud during the embryogenesis which can be unilateral or bilateral. We report unilateral dysplastic kidney with extremely large cyst diagnosed by routine ultrasonography in the 32nd week of gestational age with high levels of CA 19-9 in cystic and amniotic fluid, as well as persistent high urinary levels of this tumor marker during the 1-year follow-up. Persistent high urinary CA 19-9 level even after cyst aspiration may be attributable to remained function of dysplastic kidney due to remained epithelial lining.

  12. The relationship between Lewis/Secretor genotypes and serum carbohydrate antigen 19-9 levels in a Korean population.

    Science.gov (United States)

    Park, Hyung-Doo; Park, Kyoung Un; Song, Junghan; Ki, Chang-Seok; Han, Kyou Sup; Kim, Jin Q

    2010-02-01

    The Lewis histo-blood group system consists of 2 major antigens-Lea and Leb-and a sialyl Lewis antigen-carbohydrate antigen (CA) 19-9. We investigated the distribution of Lewis genotypes and evaluated the relationship between the Lewis/Secretor genotypes and the serum level of CA 19-9 in a Korean population to identify whether the serum CA 19-9 levels are influenced by the Lewis/Secretor genotypes. The study included 242 individuals who had no malignancies. Lewis genotyping was performed for the 59T>G, 508G>A and 1067T>A polymorphic sites. The Secretor genotype was determined through analysis of the 357C>T and 385A>T polymorphic sites and the fusion gene. Serum CA 19-9 level was analyzed using an electrochemiluminescence immunoassay. Individuals carrying the 3 common genotypes-Le/Le, Le/le(59,508), and Le/le(59,1067)-accounted for 95% of the study population. In the Korean population, the allelic frequencies of Le, Le(59), le(59,508), and le(59,1067) were 0.731, 0.010, 0.223, and 0.035, respectively. We found a significant difference in serum CA 19-9 concentrations among the 9 Lewis/Secretor genotype groups (PLewis genotypes in Koreans. Because serum CA 19-9 levels are significantly influenced by the Lewis/Secretor genotypes, caution is suggested when interpreting the serum CA 19-9 levels.

  13. 22 CFR 19.9-4 - Effect on annuitant.

    Science.gov (United States)

    2010-04-01

    ... than annuity, shall be reduced by the amount of the pension payment(s). Such salary reductions shall be... THE FOREIGN SERVICE RETIREMENT AND DISABILITY SYSTEM § 19.9-4 Effect on annuitant. Any pension payable... deducted from the annuity of the principal. (See § 19.6-4 concerning retroactive adjustments.) If...

  14. Delayed radiation-induced inflammation accompanying a marked carbohydrate antigen 19-9 elevation in a patient with resected pancreatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mattes, Malcolm D.; Cardinal, Jon S.; Jacobson, Geraldine M. [West Virginia University School of Medicine, Morgantown (United States)

    2016-06-15

    Although carbohydrate antigen (CA) 19-9 is a useful tumor marker for pancreatic cancer, it can also become elevated from a variety of benign and malignant conditions. Herein we describe an unusual presentation of elevated CA 19-9 in an asymptomatic patient who had previously undergone adjuvant chemotherapy and radiation therapy for resected early stage pancreatic cancer. The rise in CA 19-9 might be due to delayed radiation-induced inflammation related to previous intra-abdominal radiation therapy with or without radiation recall induced by gemcitabine. After treatment with corticosteroids the CA 19-9 level decreased to normal, and the patient has not developed any evidence of recurrent cancer to date.

  15. Prognostic Significance of Carbohydrate Antigen 19-9 in Unresectable Locally Advanced Pancreatic Cancer Treated With Dose-Escalated Intensity Modulated Radiation Therapy and Concurrent Full-Dose Gemcitabine: Analysis of a Prospective Phase 1/2 Dose Escalation Study

    Energy Technology Data Exchange (ETDEWEB)

    Vainshtein, Jeffrey M., E-mail: jvainsh@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Matthew [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Zalupski, Mark M. [Division of Hematology Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (United States); Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Abrams, Ross [Department of Radiation Oncology, Rush Medical Center, Chicago, Illinois (United States); Francis, Isaac R. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Khan, Gazala [Division of Hematology Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (United States); Leslie, William [Division of Hematology Oncology, Department of Internal Medicine, Rush Medical Center, Chicago, Illinois (United States); Ben-Josef, Edgar [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States)

    2013-05-01

    Purpose: Although established in the postresection setting, the prognostic value of carbohydrate antigen 19-9 (CA19-9) in unresectable locally advanced pancreatic cancer (LAPC) is less clear. We examined the prognostic utility of CA19-9 in patients with unresectable LAPC treated on a prospective trial of intensity modulated radiation therapy (IMRT) dose escalation with concurrent gemcitabine. Methods and Materials: Forty-six patients with unresectable LAPC were treated at the University of Michigan on a phase 1/2 trial of IMRT dose escalation with concurrent gemcitabine. CA19-9 was obtained at baseline and during routine follow-up. Cox models were used to assess the effect of baseline factors on freedom from local progression (FFLP), distant progression (FFDP), progression-free survival (PFS), and overall survival (OS). Stepwise forward regression was used to build multivariate predictive models for each endpoint. Results: Thirty-eight patients were eligible for the present analysis. On univariate analysis, baseline CA19-9 and age predicted OS, CA19-9 at baseline and 3 months predicted PFS, gross tumor volume (GTV) and black race predicted FFLP, and CA19-9 at 3 months predicted FFDP. On stepwise multivariate regression modeling, baseline CA19-9, age, and female sex predicted OS; baseline CA19-9 and female sex predicted both PFS and FFDP; and GTV predicted FFLP. Patients with baseline CA19-9 ≤90 U/mL had improved OS (median 23.0 vs 11.1 months, HR 2.88, P<.01) and PFS (14.4 vs 7.0 months, HR 3.61, P=.001). CA19-9 progression over 90 U/mL was prognostic for both OS (HR 3.65, P=.001) and PFS (HR 3.04, P=.001), and it was a stronger predictor of death than either local progression (HR 1.46, P=.42) or distant progression (HR 3.31, P=.004). Conclusions: In patients with unresectable LAPC undergoing definitive chemoradiation therapy, baseline CA19-9 was independently prognostic even after established prognostic factors were controlled for, whereas CA19-9 progression

  16. Marcador tumoral CA 19.9 aumentado sin evidencia de malignidad Elevated Ca 19.9 tumor marker without evidence of malignancy

    OpenAIRE

    Eduardo González Bosquet

    2007-01-01

    Los marcadores tumorales son de gran utilidad clínica en el seguimiento de los pacientes oncológicos. Su papel en el diagnóstico de tumoraciones malignas es controvertido. Presentamos un caso de una mujer con un quiste ovárico benigno en la cual los marcadores aumentan de forma inexplicable después de la extirpación del mismo.Tumor markers are a useful tool for surveillance of oncologic patients, whereas their role in the diagnosis of a malignancy is controversial. We present the case of a wo...

  17. Reversible high blood CEA and CA19-9 concentrations in a diabetic ...

    African Journals Online (AJOL)

    general malaise and body weight loss for almost 6 months. He came to our ... obesity, rapid deterioration of hyperglycemia, or elevation of tumor markers or ... image suggested the presence of a subclinical, mild form of pancreatitis, which may ...

  18. Low-affinity Ca2+ indicators compared in measurements of skeletal muscle Ca2+ transients.

    Science.gov (United States)

    Hollingworth, Stephen; Gee, Kyle R; Baylor, Stephen M

    2009-10-07

    The low-affinity fluorescent Ca(2+) indicators OGB-5N, Fluo-5N, fura-5N, Rhod-5N, and Mag-fluo-4 were evaluated for their ability to accurately track the kinetics of the spatially averaged free Ca(2+) transient (Delta[Ca(2+)]) in skeletal muscle. Frog single fibers were injected with one of the above indicators and, usually, furaptra (previously shown to rapidly track Delta[Ca(2+)]). In response to an action potential, the full duration at half-maximum of the indicator's fluorescence change (DeltaF) was found to be larger with OGB-5N, Fluo-5N, fura-5N, and Rhod-5N than with furaptra; thus, these indicators do not track Delta[Ca(2+)] with kinetic fidelity. In contrast, the DeltaF time course of Mag-fluo-4 was identical to furaptra's; thus, Mag-fluo-4 also yields reliable kinetic information about Delta[Ca(2+)]. Mag-fluo-4's DeltaF has a larger signal/noise ratio than furaptra's (for similar indicator concentrations), and should thus be more useful for tracking Delta[Ca(2+)] in small cell volumes. However, because the resting fluorescence of Mag-fluo-4 probably arises largely from indicator that is bound with Mg(2+), the amplitude of the Mag-fluo-4 signal, and its calibration in Delta[Ca(2+)] units, is likely to be more sensitive to variations in [Mg(2+)] than furaptra's.

  19. Clinical significance of serum carbohydrate antigen 19-9 and its relationship with blood glucose in patients with type 2 diabetes

    Institute of Scientific and Technical Information of China (English)

    武秀玲

    2013-01-01

    Objective To study the relationship between serum carbohydrate antigen 19-9 (CA19-9) and blood glucose level in patients with type 2 diabetes (T2DM) .Methods Totally 784 T2DM patients and 197 healthy controls were enrolled in this study.Age,duration,body mass index (BMI) ,systolic blood pressure (SBP) ,diastolic blood pressure (DBP) ,levels of fasting blood glucose (FBG) ,postprandial blood glucose (PBG) ,hemoglobin A1c (HbA1c) ,total cholesterol (TC) ,triglyceride (TG) ,

  20. Diagnostic sensitivity of serum carcinoembryonic antigen, carbohydrate antigen 19-9, alpha-fetoprotein, and beta-human chorionic gonadotropin in esophageal carcinoma (receiver operating characteristic curve analysis

    Directory of Open Access Journals (Sweden)

    Bhawna Bagaria

    2015-01-01

    Full Text Available Background: Esophageal carcinomas are very lethal disease relatively unresponsive to therapy. The continued development of new and more effective chemotherapeutic agents and regimens offers hope that in the future, this carcinoma may be amenable to either more effective palliative treatment or possibly increased cure. We, therefore, aimed to evaluate the marker with best diagnostic sensitivity in esophageal carcinoma. Materials and Methods: Serum carcinoembryonic antigen (CEA, carbohydrate antigen 19-9 (CA19-9, alpha-fetoprotein (AFP, and beta-human chorionic gonadotropin (β-HCG levels were assessed in healthy subjects (n = 50 and patients (n = 50 initially diagnosed of esophageal carcinoma by endoscopic examination and biopsy before receiving any therapy. The data were analyzed using SPSS software version 10.0 (SPSS Inc. USA and MedCalc to estimate mean ± standard deviation, the significance of the observed differences (P value, for calculating sensitivity and for plotting receiver operating characteristic curves. Results: Sensitivity of CEA, CA19-9, AFP, and β-HCG detected in esophagus cancer was 38%, 18%, 10%, and 26% respectively. Conclusion: From the above studied markers, CEA has the highest sensitivity followed by β-HCG, CA19-9 and AFP. Although the sensitivity of tumor markers in esophagus cancer is low, they may be useful additional parameter in the prediction of neoplasms involved at the early stage of tumor growth.

  1. A novel sandwich electrochemiluminescence immunosensor for ultrasensitive detection of carbohydrate antigen 19-9 based on immobilizing luminol on Ag@BSA core/shell microspheres.

    Science.gov (United States)

    Zhang, Amin; Xiang, Hongkun; Zhang, Xin; Guo, Weiwei; Yuan, Enhui; Huang, Chusen; Jia, Nengqin

    2016-01-15

    A novel sandwich-type electrochemiluminescence immunosensor based on immobilizing luminol on Ag@BSA core/shell microspheres (Ag@BSA-luminol) for ultrasensitive detection of tumor marker carbohydrate antigen 19-9 (CA19-9) has been developed. Herein, magnetic carbon nanotubes (MAGCNTs) decorated with polyethylenimine (PEI) was used to construct the base of the immunosensor. MAGCNTs with prominent electrical conductivity and high surface area could be beneficial for promoting the electron transfer and loading plenty of primary antibodies (Ab1) via glutaraldehyde (GA). Meanwhile, the magnetic property of MAGCNTs makes it easy to be attached to the surface of magnetic glass carbon electrode (MGCE) through magnetism interaction, which provides an outstanding platform for this immunosensor. Moreover, Ag@BSA microspheres with large surface area, good stability, and excellent biocompatibility were desirable candidates for effective cross-link of CA19-9 detection antibodies (Ab2). A more interesting thing was that ELISA color reaction was used as an ultrasensitive strategy for identifying Ab2 was successfully coated on Ag@BSA with the naked eye. Additionally, we immobilized the luminol on the surface of Ag@BSA to prepare the target immunosensor. Immobilization of luminol on the surface of Ag@BSA could decrease the distance between luminophores and the electrode surface, leading to great enhancement of the ECL intensity of luminol in the present of hydrogen peroxide (H2O2). Under the optimal conditions, the intensity of the ECL immunosensor increased linearly with the logarithm of CA19-9 concentration in a wide linear range from 0.0005 to 150UmL(-1) with a detection limit of 0.0002UmL(-1) (S/N=3). All the results suggested the prepared CA19-9 immunosensor displayed high sensitivity, excellent stability and good specificity. The developed method opened a new avenue to clinical bioassay.

  2. Significance of correlation between levels of carcinoembryonic antigen and carbohydrate antigen 19-9, carcinoembryonic antigen and C-reactive protein, carcinoembryonic antigen and alpha-1 antitrypsin in gastric and colon cancer patients

    Directory of Open Access Journals (Sweden)

    Bhawna Bagaria

    2014-01-01

    Full Text Available Aim: Recent progress in proteomics studies profiled that serum proteins of cancer patients and those of normal individuals have altered cancer antigen and acute phase protein expression for distinct types and stages of cancer. In our study, correlation between carcinoembryonic antigen (CEA and carbohydrate antigen (CA 19-9, CEA and C-reactive protein (CRP, CEA and alpha-1 antitrypsin (A1AT were evaluated in gastric and colon cancer patients. Materials and Methods: CEA was estimated by solid phase, two-site sequential chemiluminescent immunometric assay, CA19-9 by solid phase enzyme-linked immunosorbent assay, CRP by latex turbidimetry method and A1AT by turbidimetry method. Results: A significant correlation was seen in levels of CEA and CA19-9 in gastric (r = 0.457, P < 0.001 and colon cancer (r = 0.451, P < 0.001 patients. Correlation between CEA and CRP was significant in gastric (r = 0.462, P < 0.001 and colon cancer (r = 0.759, P < 0.001 patients and between CEA and A1AT also, correlation was found to be significant in gastric (r = 0.631, P < 0.001 and colon cancer patients (r = 0.516, P ≤ 0.001. Conclusion: Serum acute-phase protein concentrations, when combined with CEA increases the sensitivity of CEA and provide substantial information concerning the diagnosis of gastrointestinal cancers. They have a definite role as a significant prognostic indicator which undoubtedly correlates with progression of cancer. Combined CEA and CA19-9 positivity reflected more biologic malignant properties and were significantly correlated with lymph node metastasis, hepatic metastasis and lower rates of curative resection. Surgical outcomes of patients who were CEA and CA19-9 positive were poorer than those of patients with normal CEA and CA19-9 levels.

  3. Ca(2+)-dependent permeabilization of mitochondria and liposomes by palmitic and oleic acids: a comparative study.

    Science.gov (United States)

    Belosludtsev, Konstantin N; Belosludtseva, Natalia V; Agafonov, Alexey V; Astashev, Maxim E; Kazakov, Alexey S; Saris, Nils-Erik L; Mironova, Galina D

    2014-10-01

    In the present work, we examine and compare the effects of saturated (palmitic) and unsaturated (oleic) fatty acids in relation to their ability to cause the Ca(2+)-dependent membrane permeabilization. The results obtained can be summarized as follows. (1) Oleic acid (OA) permeabilizes liposomal membranes at much higher concentrations of Ca(2+) than palmitic acid (PA): 1mM versus 100μM respectively. (2) The OA/Ca(2+)-induced permeabilization of liposomes is not accompanied by changes in the phase state of lipid bilayer, in contrast to what is observed with PA and Ca(2+). (3) The addition of Ca(2+) to the PA-containing vesicles does not change their size; in the case of OA, it leads to the appearance of larger and smaller vesicles, with larger vesicles dominating. This can be interpreted as a result of fusion and fission of liposomes. (4) Like PA, OA is able to induce a Ca(2+)-dependent high-amplitude swelling of mitochondria, yet it requires higher concentrations of Ca(2+) (30 and 100μM for PA and OA respectively). (5) In contrast to PA, OA is unable to cause the Ca(2+)-dependent high-amplitude swelling of mitoplasts, suggesting that the cause of OA/Ca(2+)-induced permeability transition in mitochondria may be the fusion of the inner and outer mitochondrial membranes. (6) The presence of OA enhances PA/Ca(2+)-induced permeabilization of liposomes and mitochondria. The paper discusses possible mechanisms of PA/Ca(2+)- and OA/Ca(2+)-induced membrane permeabilization, the probability of these mechanisms to be realized in the cell, and their possible physiological role.

  4. 15 CFR 19.9 - When will Commerce entities transfer a Commerce debt to the Treasury Department's Financial...

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false When will Commerce entities transfer a Commerce debt to the Treasury Department's Financial Management Service for collection? 19.9 Section 19.9 Commerce and Foreign Trade Office of the Secretary of Commerce COMMERCE DEBT COLLECTION Procedures...

  5. Assessment of a serum tumour marker for carcinoma of the pancreas: the carbohydrate antigen C. A. 19-9

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, D.; Venot, J.; Catanzano, G.; Clement, M.N.; Piquet, M.F.; Veyriras, E.; Beck, C. (C.H.U. Dupuytren, 87 - Limoges (France))

    1985-01-01

    A radio-immunological assay with monoclonal antibodies was used to measure the C 19-9 antigen in 51 patients to determine its diagnostic value in cancer of the pancreas. The results show that the C 19-9 antigen is a good marker for carcinoma of the pancreas and that it can be commonly used.

  6. Comparative identification of Ca2+ channel expression in INS-1 and rat pancreatic β cells

    Institute of Scientific and Technical Information of China (English)

    Fei Li; Zong-Ming Zhang

    2009-01-01

    AIM: To identify and compare the profile of Ca2+ channel subunit expression in INS-1 and rat pancreatic β cells. METHODS: The rat insulin-secreting INS-1 cell line was cultured in RPMI-1640 with Wistar rats employed as islet donors. Ca2+ channel subunit expression in INS-1 and isolated rat β cells were examined by reverse transcription polymerase chain reaction (RT-PCR). Absolute real-time quantitative PCR was performed in a Bio-Rad iQ5 Gradient Real Time PCR system and the data analyzed using an iQ5 system to identify the expression level of the Ca2+ channel subunits. RESULTS: In INS-1 cells, the L-type Ca2+ channel 1C subunit had the highest expression level and the TPRM2 subunit had the second highest expression. In rat β cells, the TPRC4β subunit expression was dominant and the expression of the L-type 1C subunit exceeded the 1D subunit expression about two-fold. This result agreed with other studies, confirming the important role of the L-type 1C subunit in insulinsecreting cells, and suggested that non-voltageoperated Ca2+ channels may have an important role in biphasic insulin secretion. CONCLUSION: Twelve major Ca2+ channel subunit types were identified in INS-1 and rat β cells and significant differences were observed in the expression of certain subunits between these cells.

  7. Amperometric carbohydrate antigen 19-9 immunosensor based on three dimensional ordered macroporous magnetic Au film coupling direct electrochemistry of horseradish peroxidase

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qi [College of Sciences, Nanjing Tech University, Nanjing 211816 (China); Chen, Xiaojun, E-mail: chenxj_njut@126.com [College of Sciences, Nanjing Tech University, Nanjing 211816 (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China); Tang, Yin [Zhangjiagang Hospital of Traditional Chinese Medicine, Zhangjiagang 215600 (China); Ge, Lingna; Guo, Buhua [College of Sciences, Nanjing Tech University, Nanjing 211816 (China); Yao, Cheng, E-mail: yaochengnjut@163.com [College of Sciences, Nanjing Tech University, Nanjing 211816 (China)

    2014-03-01

    Highlights: • Three dimensional ordered macroporous magnetic electrode was newly used in electrochemical immunosensor. • The large surface area of macroporous magnetic electrode could improve the immobilized amount of antibody. • Au nanoparticles functionalized SBA-15 was used to immobilize enzyme labeled Ab₂ and enzyme. • Macroporous magnetic electrode and Au nanoparticles composite facilitated the direct electron transfer of enzyme. • The immunoassay avoided adding electron transfer mediator, simplifying the procedure. Abstract: A sandwich-type electrochemical immunosensor for the detection of carbohydrate antigen 19-9 (CA 19-9) antigen based on the immobilization of primary antibody (Ab₁) on three dimensional ordered macroporous magnetic (3DOMM) electrode, and the direct electrochemistry of horseradish peroxidase (HRP) that was used as both the label of secondary antibody (Ab₂) and the blocking reagent. The 3DOMM electrode was fabricated by introducing core–shell Au–SiO₂@Fe₃O₄ nanospheres onto the surface of three dimensional ordered macroporous (3DOM) Au electrode via the application of an external magnet. Au nanoparticles functionalized SBA-15 (Au@SBA-15) was conjugated to the HRP labeled secondary antibody (HRP-Ab₂) through the Au–SH or Au–NH₃⁺ interaction, and HRP was also used as the block reagent. The formation of antigen–antibody complex made the combination of Au@SBA-15 and 3DOMM exhibit remarkable synergistic effects for accelerating direct electron transfer (DET) between HRP and the electrode. Under the optimal conditions, the DET current signal increased proportionally to CA 19-9 concentration in the range of 0.05 to 15.65 U mL⁻¹ with a detection limit of 0.01 U mL⁻¹. Moreover, the immunosensor showed high selectivity, good stability, satisfactory reproducibility and regeneration. Importantly, the developed method was used to assay clinical serum specimens, achieving a good relation with those obtained from

  8. Diagnostic and Prognostic Impact of Circulating YKL-40, IL-6, and CA 19.9 in Patients with Pancreatic Cancer

    DEFF Research Database (Denmark)

    Schultz, Nicolai A; Christensen, Ib Jarle; Werner, Jens;

    2013-01-01

    We tested the hypothesis that high plasma YKL-40 and IL-6 associate with pancreatic cancer and short overall survival.......We tested the hypothesis that high plasma YKL-40 and IL-6 associate with pancreatic cancer and short overall survival....

  9. Comparative studies of cardiac and skeletal sarcoplasmic reticulum ATPases. Effect of a phospholamban antibody on enzyme activation by Ca2+.

    Science.gov (United States)

    Cantilina, T; Sagara, Y; Inesi, G; Jones, L R

    1993-08-15

    Vesicular fragments of skeletal (LSR) and cardiac (CSR) sarcoplasmic reticulum were compared with the aim of defining the effect of a monoclonal phospholamban (Pl) antibody (Ab). The Pl Ab has no effect on LSR, while enhancing the Ca2+ transport rates of CSR at Ca2+ concentrations below saturation. We found no direct effect of the Pl Ab on Ca2+ binding by the ATPase in the absence of ATP. Equilibrium measurements of Ca2+ binding yield positively cooperative isotherms which are best fit with a two-interacting sites equation. LSR and CSR display nearly identical affinities for Ca2+, and no effect of the Pl Ab is observed. Taking advantage of a stable CrATP-enzyme complex, we demonstrated that the stoichiometric ratio of occluded Ca2+ to catalytic sites is 2 in either LSR or CSR and that the addition of Pl Ab does not affect the Ca2+ concentration dependence of Ca2+ occluded after equilibration of the system. Interestingly, the cooperative interaction between the two Ca2+ sites is lost in the occluded state, with only one of the two sites acquiring lumenal exposure. The concentration dependence of Ca2+ inhibition of CSR ATPase phosphorylation with Pi is also unaffected by the Pl Ab. Contrary to the lack of Pl Ab effect on reactions measured at equilibrium, enhancement of phosphorylated intermediate formation by the Pl Ab is obtained in kinetic experiments in which nonsaturating Ca2+ and ATP are added to CSR preincubated with EGTA. Therefore, Ab binding to Pl reduces specifically the activation energy for a slow transition triggered by Ca2+ binding, with consequent enhancement of overall kinetics under conditions enhancing the rate-limiting contribution of this transition.

  10. Culturally adapted CBT (CA-CBT) for Latino women with treatment-resistant PTSD: a pilot study comparing CA-CBT to applied muscle relaxation.

    Science.gov (United States)

    Hinton, Devon E; Hofmann, Stefan G; Rivera, Edwin; Otto, Michael W; Pollack, Mark H

    2011-04-01

    We examined the therapeutic efficacy of a culturally adapted form of CBT (CA-CBT) for PTSD as compared to applied muscle relaxation (AMR) for female Latino patients with treatment-resistant PTSD. Participants were randomized to receive either CA-CBT (n = 12) or AMR (n = 12), and were assessed before treatment, after treatment, and at a 12-week follow-up. The treatments were manualized and delivered in the form of group therapy across 14 weekly sessions. Assessments included a measure of PTSD, anxiety, culturally relevant idioms of distress (nervios and ataque de nervios), and emotion regulation ability. Patients receiving CA-CBT improved significantly more than in the AMR condition. Effect size estimates showed very large reductions in PTSD symptoms from pretreatment to posttreatment in the CA-CBT group (Cohen's d = 2.6) but only modest improvements in the AMR group (0.8). These results suggest that CA-CBT can be beneficial for previously treatment-resistant PTSD in Latino women.

  11. Protein extraction from Ca-alginate encapsulated plant material for comparative proteomic analysis.

    Science.gov (United States)

    Domżalska, Lucyna; Mikuła, Anna; Rybczyński, Jan J

    2016-10-01

    The extensive use of encapsulation material in biotechnology drove the need to develop analytical techniques for this type of material. This study focuses on the specific problems of protein extraction from Ca-alginate encapsulated plant material. Proteomics is one of the fast-developing analysis categories, specifically for stress resistance and developmental changes in plant material. Sample preparation is a critical step in a two-dimensional gel electrophoresis proteome approach and is essential for good results. The aim was to avoid preliminary manipulations and get good quality material for comparative proteome analysis technique 2DE. The phenol extraction method and the complex method with preliminary TCA precipitation, SDS buffer and phenol phase were compared with respect to the efficiency and quality of the resulting 2DE gel. The most appropriate method turned out to be the TCA/phenol method with the phenol fractioning technique adapted to the gentian cell suspension. It resulted in a high protein concentration and good quality sample that could be analyzed using the standard separation procedures of 2DE and spectrometric identification with high efficiency. The work presented here confirms the possibility of obtaining a sufficient protein sample for effective proteomic analysis from a small number of capsules.

  12. The temporoammonic input to the hippocampal CA1 region displays distinctly different synaptic plasticity compared to the Schaffer collateral input in vivo: significance for synaptic information processing

    Science.gov (United States)

    Aksoy-Aksel, Ayla; Manahan-Vaughan, Denise

    2013-01-01

    In terms of its sub-regional differentiation, the hippocampal CA1 region receives cortical information directly via the perforant (temporoammonic) path (pp-CA1 synapse) and indirectly via the tri-synaptic pathway where the last relay station is the Schaffer collateral-CA1 synapse (Sc-CA1 synapse). Research to date on pp-CA1 synapses has been conducted predominantly in vitro and never in awake animals, but these studies hint that information processing at this synapse might be distinct to processing at the Sc-CA1 synapse. Here, we characterized synaptic properties and synaptic plasticity at the pp-CA1 synapse of freely behaving adult rats. We observed that field excitatory postsynaptic potentials at the pp-CA1 synapse have longer onset latencies and a shorter time-to-peak compared to the Sc-CA1 synapse. LTP (>24 h) was successfully evoked by tetanic afferent stimulation of pp-CA1 synapses. Low frequency stimulation evoked synaptic depression at Sc-CA1 synapses, but did not elicit LTD at pp-CA1 synapses unless the Schaffer collateral afferents to the CA1 region had been severed. Paired-pulse responses also showed significant differences. Our data suggest that synaptic plasticity at the pp-CA1 synapse is distinct from the Sc-CA1 synapse and that this may reflect its specific role in hippocampal information processing. PMID:23986697

  13. The temporoammonic input to the hippocampal CA1 region displays distinctly different synaptic plasticity compared to the Schaffer collateral input in vivo: significance for synaptic information processing

    Directory of Open Access Journals (Sweden)

    Ayla eAksoy Aksel

    2013-08-01

    Full Text Available In terms of its sub-regional differentiation, the hippocampal CA1 region receives cortical information directly via the perforant (temporoammonic path (pp-CA1 synapse and indirectly via the tri-synaptic pathway where the last relay station is the Schaffer collateral-CA1 synapse (Sc-CA1 synapse. Research to date on pp-CA1 synapses has been conducted predominantly in vitro and never in awake animals, but these studies hint that information processing at this synapse might be distinct to processing at the Sc-CA1 synapse. Here, we characterized synaptic properties and synaptic plasticity at the pp-CA1 synapse of freely behaving adult rats. We established that field excitatory postsynaptic potentials at the pp-CA1 have longer onset latencies and a shorter time-to-peak compared to the Sc-CA1 synapse. LTP (> 24h was successfully evoked by tetanic afferent stimulation of pp-CA1 synapses. Low frequency stimulation evoked synaptic depression at Sc-CA1 synapses, but did not elicit LTD at pp-CA1 synapses unless the Schaffer collateral afferents to the CA1 region had been severed. Paired-pulse responses also showed significant differences. Our data suggest that synaptic plasticity at the pp-CA1 synapse is distinct from the Sc-CA1 synapse and that this may reflect its specific role in hippocampal information processing.

  14. A comparative study on Ca content and distribution in two Gesneriaceae species reveals distinctive mechanisms to cope with high rhizospheric soluble calcium.

    Science.gov (United States)

    Li, Wenlong; Xu, Falun; Chen, Shixuan; Zhang, Zhennan; Zhao, Yan; Jin, Yukuan; Li, Meijing; Zhu, Yan; Liu, Yongxiu; Yang, Yi; Deng, Xin

    2014-01-01

    Excessive Ca is toxic to plants thus significantly affects plant growth and species distribution in Ca-rich karst areas. To understand how plants survive high Ca soil, laboratory experiments were established to compare the physiological responses and internal Ca distribution in organ, tissue, cell, and intracellular levels under different Ca levels for Lysionotus pauciflorus and Boea hygrometrica, two karst habitant Gesneriaceae species in Southwest China. In the controlled condition, L. pauciflorus could survive as high as 200 mM rhizospheric soluble Ca, attributed to a series of physiological responses and preferential storage that limited Ca accumulation in chloroplasts of palisade cells. In contrast, B. hygrometrica could survive only 20 mM rhizospheric soluble Ca, but accumulated a high level of internal Ca in both palisade and spongy cells without disturbance on photosynthetic activity. By phenotype screening of transgenic plants expressing high Ca-inducible genes from B. hygrometrica, the expression of BhDNAJC2 in A. thaliana was found to enhance plant growth and photosynthesis under high soluble Ca stress. BhDNAJC2 encodes a recently reported heat shock protein (HSP) 40 family DnaJ-domain protein. The Ca-resistant phenotype of BhDNAJC2 highlights the important role of chaperone-mediated protein quality control in Ca tolerance in B. hygrometrica. Taken together, our results revealed that distinctive mechanisms were employed in the two Gesneriaceae karst habitants to cope with a high Ca environment.

  15. A comparative study on Ca content and distribution in two Gesneriaceae species reveals distinctive mechanisms to cope with high rhizospheric soluble calcium

    Directory of Open Access Journals (Sweden)

    Wenlong eLi

    2014-11-01

    Full Text Available Excessive Ca is toxic to plants thus significantly affects plant growth and species distribution in Ca-rich karst areas. To understand how plants survive high Ca soil, laboratory experiments were established to compare the physiological responses and internal Ca distribution in organ, tissue, cell and intracellular levels under different Ca levels for Lysionotus pauciflorus and Boea hygrometrica, two karst habitant Gesneriaceae species in Southwest China. In the controlled condition, L. pauciflorus could survive as high as 200 mM rhizospheric soluble Ca, attributed to a series of physiological responses and preferential storage that limited Ca accumulation in chloroplasts of palisade cells. In contrast, B. hygrometrica could survive only 20 mM rhizospheric soluble Ca, but accumulated a high level of internal Ca in both palisade and spongy cells without disturbance on photosynthetic activity. By phenotype screening of transgenic plants expressing high Ca-inducible genes from B. hygrometrica, the expression of BhDNAJC2 in A. thaliana was found to enhance plant growth and photosynthesis under high soluble Ca stress. BhDNAJC2 encodes a recently reported heat shock protein (HSP 40 family DnaJ-domain protein. The Ca-resistant phenotype of BhDNAJC2 highlights the important role of chaperone-mediated protein quality control in Ca tolerance in B. hygrometrica. Taken together, our results revealed that distinctive mechanisms were employed in the two Gesneriaceae karst habitants to cope with a high Ca environment.

  16. Preparation of 45Ca(HDEHP)n and (CaH{sub 1}50{sub 2})2 samples for liquid scintillation counting, compared to 45caCl{sub 2} results; Preparacion de Ca (HDEHP)n y (C{sub 8}H{sub 1}50{sub 2})2 marcados con 45Ca y estudio comparativo con 4 5ca Cl2 en medidas por centelleo liquido

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L.; Arcos, J. M. los; Grau Malonda, A.

    1994-07-01

    A procedure for preparation of liquid scintillation counting organic samples of the Di-2-ethylhexyl phosphate calcium complex and the 2-ethylhexanoate calcium salt, labelled with 45Ca, is described. The chemical quench, the counting stability and spectral evolution of both compounds is studied in six scintillators,Toluene-alcohol, Dioxane-naphtalene, Hi safe II, Ultimate-Gold and Instagel, and compared to results obtained from a commercial solution of 4 5CaCl2. (Author) 7 refs.

  17. Comparative Diagnostic Accuracy of the ACE-III, MIS, MMSE, MoCA, and RUDAS for Screening of Alzheimer Disease.

    Science.gov (United States)

    Matías-Guiu, Jordi A; Valles-Salgado, María; Rognoni, Teresa; Hamre-Gil, Frank; Moreno-Ramos, Teresa; Matías-Guiu, Jorge

    2017-01-01

    Our aim was to evaluate and compare the diagnostic properties of 5 screening tests for the diagnosis of mild Alzheimer disease (AD). We conducted a prospective and cross-sectional study of 92 patients with mild AD and of 68 healthy controls from our Department of Neurology. The diagnostic properties of the following tests were compared: Mini-Mental State Examination (MMSE), Addenbrooke's Cognitive Examination III (ACE-III), Memory Impairment Screen (MIS), Montreal Cognitive Assessment (MoCA), and Rowland Universal Dementia Assessment Scale (RUDAS). All tests yielded high diagnostic accuracy, with the ACE-III achieving the best diagnostic properties. The area under the curve was 0.897 for the ACE-III, 0.889 for the RUDAS, 0.874 for the MMSE, 0.866 for the MIS, and 0.856 for the MoCA. The Mini-ACE score from the ACE-III showed the highest diagnostic capacity (area under the curve 0.939). Memory scores of the ACE-III and of the RUDAS showed a better diagnostic accuracy than those of the MMSE and of the MoCA. All tests, especially the ACE-III, conveyed a higher diagnostic accuracy in patients with full primary education than in the less educated group. Implementing normative data improved the diagnostic accuracy of the ACE-III but not that of the other tests. The ACE-III achieved the highest diagnostic accuracy. This better discrimination was more evident in the more educated group. © 2017 S. Karger AG, Basel.

  18. Stringent control of cytoplasmic Ca2+ in guard cells of intact plants compared to their counterparts in epidermal strips or guard cell protoplasts.

    Science.gov (United States)

    Levchenko, V; Guinot, D R; Klein, M; Roelfsema, M R G; Hedrich, R; Dietrich, P

    2008-01-01

    Cytoplasmic calcium elevations, transients, and oscillations are thought to encode information that triggers a variety of physiological responses in plant cells. Yet Ca(2+) signals induced by a single stimulus vary, depending on the physiological state of the cell and experimental conditions. We compared Ca(2+) homeostasis and stimulus-induced Ca(2+) signals in guard cells of intact plants, epidermal strips, and isolated protoplasts. Single-cell ratiometric imaging with the Ca(2+)-sensitive dye Fura 2 was applied in combination with electrophysiological recordings. Guard cell protoplasts were loaded with Fura 2 via a patch pipette, revealing a cytoplasmic free Ca(2+) concentration of around 80 nM at -47 mV. Upon hyperpolarization of the plasma membrane to -107 mV, the Ca(2+) concentration increased to levels exceeding 400 nM. Intact guard cells were able to maintain much lower cytoplasmic free Ca(2+) concentrations at hyperpolarized potentials, the average concentration at -100 mV was 183 and 90 nM in epidermal strips and intact plants, respectively. Further hyperpolarization of the plasma membrane to -160 mV induced a sustained rise of the guard cell cytoplasmic Ca(2+) concentration, which slowly returned to the prestimulus level in intact plants but not in epidermal strips. Our results show that cytoplasmic Ca(2+) concentrations are stringently controlled in guard cells of intact plants but become increasingly more sensitive to changes in the plasma membrane potential in epidermal strips and isolated protoplasts.

  19. A Comparative Study of Apical Healing of Open Apices Using MTA and Ca(OH2 Apical Plugs in Cats

    Directory of Open Access Journals (Sweden)

    M. H. Zarrabi

    2005-06-01

    Full Text Available Statement of problem: Endodontic treatment of necrotic teeth with open apices is a challenge. After ruling out surgery as a treatment scheme and introduction of the multivisit apexification which in turn had its disadvantages, apical plug seems to be a suitable substitute treatment plan for such cases. Apical plug makes the treatment through formation of a barrier against the obturating material in a single visit.Purpose: The purpose of this study was to compare histologically the periapical healing using MTA and calcium hydroxide apical plugs after intervals of 4 and 12 weeks in cats.Materials and Methods: In this clinical trial study 64 canines of 16 healthy and mature cats were divided into 3 groups after a periapical lesion formation by over instrumentation in the apical area with files up to no.120. The first group included 24 teeth on which MTA apical plug was applied. The second group included 24 teeth on which Ca (OH 2 apical plug was applied. In both groups the canals were filled with gutta percha and sealer. The third group included 16 control teeth whose canals were left empty after instrumentation and debridement. The access cavities of all teeth were sealed with varnish and amalgam and the vital perfusion of cats was performed in 4 and 12 week intervals. Statistical analysis was established by χ2 and independence test.Results: After 4 weeks, periapical healing in the first group was 90%, in the second group 80% and in the third group, it was only 12.5 %. After 12 weeks, periapical healing occurred in 100% of the MTA group, while it was 57.1% in the second and 40%in the third group .Generally, in the study of histological parameters of healing, no statistical significant difference was observed between the 2 experimental groups,although the MTA group results were much better than the Ca (OH 2 group especially at 12 weeks.Conclusion: The use of MTA apical plug is more effective than Ca (OH 2 in treatment of necrotic teeth with open

  20. Deconstructing complexin function in activating and clamping Ca2+-triggered exocytosis by comparing knockout and knockdown phenotypes.

    Science.gov (United States)

    Yang, Xiaofei; Cao, Peng; Südhof, Thomas C

    2013-12-17

    Complexin, a presynaptic protein that avidly binds to assembled SNARE complexes, is widely acknowledged to activate Ca(2+)-triggered exocytosis. In addition, studies of invertebrate complexin mutants and of mouse neurons with a double knockdown (DKD) of complexin-1 and -2 suggested that complexin maintains the readily releasable pool (RRP) of vesicles and clamps spontaneous exocytosis. In contrast, studies of mouse neurons with a double knockout (DKO) of complexin-1 and -2, largely carried out in hippocampal autapses, did not detect changes in the RRP size or in spontaneous exocytosis. To clarify complexin function, we here directly compared in two different preparations, cultured cortical and olfactory bulb neurons, the phenotypes of complexin DKD and DKO neurons. We find that complexin-deficient DKD and DKO neurons invariably exhibit a ~50% decrease in vesicle priming. Moreover, the DKD consistently increased spontaneous exocytosis, but the DKO did so in cortical but not olfactory bulb neurons. Furthermore, the complexin DKD but not the complexin DKO caused a compensatory increase in complexin-3 and -4 mRNA levels; overexpression of complexin-3 but not complexin-1 increased spontaneous exocytosis. Complexin-3 but not complexin-1 contains a C-terminal lipid anchor attaching it to the plasma membrane; addition of a similar lipid anchor to complexin-1 converted complexin-1 from a clamp into an activator of spontaneous exocytosis. Viewed together, our data suggest that complexin generally functions in priming and Ca(2+) triggering of exocytosis, and additionally contributes to the control of spontaneous exocytosis dependent on the developmental history of a neuron and on the subcellular localization of the complexin.

  1. Analysis of tumor marker CA 125 in saliva of normal and oral squamous cell carcinoma patients: a comparative study.

    Science.gov (United States)

    Balan, Jude J; Rao, Roopa S; Premalatha, B R; Patil, Shankargouda

    2012-09-01

    The mortality and morbidity associated with oral squamous cell carcinoma (OSCC) can be greatly reduced if tumor markers which can detect OSCC at an early stage are available. The use of saliva as an alternative to blood could provide a substantial advantage in sampling convenience. Cancer antigen 125 (CA 125) is a tumor-associated antigen found to be increased in epithelial tumors like oral, breast and ovarian cancers. To determine whether salivary CA 125 levels are increased significantly in OSCC patients than the control group. Sixty OSCC patients and 60 healthy controls were taken for the study. Saliva samples from both the groups were collected, centrifuged and supernatant fluid were subjected to ELISA for assessment of CA 125. The mean salivary CA 125 values of OSCC patients and control group were statistically analyzed using Mann-Whitney U-test. The mean salivary CA 125 concentration of OSCC group was 320.25 and that of control group was 33.14. Thus, CA 125 was found to be significantly increased in the saliva of OSCC patients than the control group (p convenience, reliability and noninvasive nature of salivary CA 125 testing makes it a feasible adjunctive diagnostic tool for detection of OSCC.

  2. Levels of CEA and Ca 19 - 9 in the sera and peritoneal cavity in patients with gastric and pancreatic cancers Níveis de CEA e Ca 19 - 9 em soro e cavidade peritoneal em pacientes com câncer do estômago e pâncreas

    OpenAIRE

    David Hoskovec; Jozef Varga; Ellen Konečná; František Antoš

    2012-01-01

    PURPOSE: Tumor markers are substances found in blood and other biological fluids if tumor is present in the body. They can be produced by tumor itself or can be results of cancer - body relation. They may be used in the follow-up of cancer patients to identify tumor recurrence. Pre-treatment levels have prognostic tool and could signalize persistence of minimal residual disease despite radical surgery. METHODS: We operated on 52 patients with upper GI malignancy (32 with gastric cancer and 20...

  3. Synthesis, crystal structure refinement, and nonlinear-optical properties of CaB{sub 3}O{sub 5}(OH): Comparative crystal chemistry of calcium triborates

    Energy Technology Data Exchange (ETDEWEB)

    Yamnova, N. A., E-mail: aks.crys@gmail.com; Aksenov, S. M. [Moscow State University, Faculty of Geology (Russian Federation); Stefanovich, S. Yu. [Moscow State University, Faculty of Chemistry (Russian Federation); Volkov, A. S.; Dimitrova, O. V. [Moscow State University, Faculty of Geology (Russian Federation)

    2015-09-15

    Calcium triborate CaB{sub 3}O5(OH) obtained by hydrothermal synthesis in the Ca(OH){sub 2}–H{sub 3}BO{sub 3}–Na{sub 2}CO{sub 3}–KCl system is studied by single-crystal X-ray diffraction. The parameters of the orthorhombic unit cell are as follows: a = 13.490(1), b = 6.9576(3), and c = 4.3930(2) Å; V = 412.32(3) Å{sup 3} and space group Pna2{sub 1}. The structure is refined in the anisotropic approximation of the atomic displacement parameters to R = 4.28% using 972 vertical bar F vertical bar > 4σ(F). It is confirmed that the crystal structure of Ca triborate CaB{sub 3}O{sub 5}(OH) is identical to that described earlier. The hydrogen atom is localized. An SHG signal stronger than that of the quartz standard is registered. The phase transition of calcium triborate into calciborite is found on heating. The comparative crystal-chemical analysis of a series of borates with the general chemical formula 2CaO · 3B{sub 2}O{sub 3} · nH{sub 2}O (n = 0–13) with the constant CaO: B{sub 2}O{sub 3}= 2: 3 ratio and variable content of water is performed.

  4. Comparative study of apatite formation on CaSiO3 ceramics in simulated body fluids with different carbonate concentrations.

    Science.gov (United States)

    Iimori, Yusuke; Kameshima, Yoshikazu; Okada, Kiyoshi; Hayashi, Shigeo

    2005-01-01

    Apatite formation on CaSiO3 ceramics was investigated using two different simulated body fluids (SBF) proposed by Kokubo (1990) and Tas (2000) and three sample/SBF (S/S) ratios (1.0, 2.5 and 8.3 mg/ml) at 36.5 degrees C for 1-25 days. The CaSiO3 ceramic was prepared by firing coprecipitated gel with Ca/Si = 0.91 at 1400 degrees C. The bulk density was 2.14 g/cm3 and the relative density about 76%. The two SBF solutions contain different concentrations of HCO3- and Cl- ions, the concentrations of which are closer to human blood plasma in the Tas SBF formulation than in the Kokubo formulation. The pH values in the former solution are also more realistic. The CaSiO3 ceramics show apatite formation in SBF (Kokubo) after soaking for only 1 day at all S/S ratios whereas different phases were formed at each S/S ratio in SBF (Tas). The crystalline phases formed were mainly apatite at S/S = 1.0 mg/ml, carbonate-type apatite at 2.5 mg/ml and calcite at 8.3 mg/ml. At higher S/S ratios the increase in the Ca concentration became higher while the P concentration became lower in the reacted SBF. These changes in SBF concentrations and increasing pH occurred at higher S/S ratios, producing more favorable conditions in the SBF for the formation of carbonate bearing phases, finally leading to the formation of calcite instead of apatite in the higher HCO3- ion concentration SBF (Tas). Apatite is, however, formed in the lower HCO3- ion concentration SBF (Kokubo) even though the Ca and P concentrations change in a similar manner to SBF (Tas).

  5. CeCaFDB: a curated database for the documentation, visualization and comparative analysis of central carbon metabolic flux distributions explored by 13C-fluxomics.

    Science.gov (United States)

    Zhang, Zhengdong; Shen, Tie; Rui, Bin; Zhou, Wenwei; Zhou, Xiangfei; Shang, Chuanyu; Xin, Chenwei; Liu, Xiaoguang; Li, Gang; Jiang, Jiansi; Li, Chao; Li, Ruiyuan; Han, Mengshu; You, Shanping; Yu, Guojun; Yi, Yin; Wen, Han; Liu, Zhijie; Xie, Xiaoyao

    2015-01-01

    The Central Carbon Metabolic Flux Database (CeCaFDB, available at http://www.cecafdb.org) is a manually curated, multipurpose and open-access database for the documentation, visualization and comparative analysis of the quantitative flux results of central carbon metabolism among microbes and animal cells. It encompasses records for more than 500 flux distributions among 36 organisms and includes information regarding the genotype, culture medium, growth conditions and other specific information gathered from hundreds of journal articles. In addition to its comprehensive literature-derived data, the CeCaFDB supports a common text search function among the data and interactive visualization of the curated flux distributions with compartmentation information based on the Cytoscape Web API, which facilitates data interpretation. The CeCaFDB offers four modules to calculate a similarity score or to perform an alignment between the flux distributions. One of the modules was built using an inter programming algorithm for flux distribution alignment that was specifically designed for this study. Based on these modules, the CeCaFDB also supports an extensive flux distribution comparison function among the curated data. The CeCaFDB is strenuously designed to address the broad demands of biochemists, metabolic engineers, systems biologists and members of the -omics community.

  6. A new human cholangiocellular carcinoma cell line (HuCC-T1) producing carbohydrate antigen 19/9 in serum-free medium.

    Science.gov (United States)

    Miyagiwa, M; Ichida, T; Tokiwa, T; Sato, J; Sasaki, H

    1989-06-01

    A human cholangiocellular carcinoma cell line, HuCC-T1, was established in vitro from the malignant cells of ascites of a 56-yr-old patient. Histologic findings of the primary liver tumor revealed a moderately differentiated adenocarcinoma. Tumor cells from the ascites have been cultured with RPMI 1640 medium containing 0.2% lactalbumin hydrolysate and the cultured cells grew as monolayers with a population doubling time of 74 h during exponential growth at Passage 25. They had an epithelial-like morphology and were positive for mucine staining. Ultrastructural studies revealed the presence of microvilli on the cell surface and poorly developed organelles in the cytoplasm. The HuCC-T1 cell was tumorigenic in nude mice. The number of chromosomes in HuCC-T1 ranged from 61 to 80. These human cholangiocellular carcinoma cells in serum-free medium secreted several tumor markers, including carbohydrate antigen 19/9, carbohydrate antigen 125, carcinoembryonic antigen, and tissue polypeptide antigen. The carbohydrate antigen 19/9 secretion level of HuCC-T1 cells cultured in RPMI 1640 medium with 1% fetal bovine serum was sixfold higher than that with 0.2% lactalbumin hydrolysate. These findings suggest that HuCC-T1 will provide useful information to clarify the mechanism of tumor marker secretion and tumor cell growth in the human cholangiocellular carcinoma.

  7. A DFT-based comparative equilibrium study of thermal dehydration and hydrolysis of CaCl₂ hydrates and MgCl₂ hydrates for seasonal heat storage.

    Science.gov (United States)

    Pathak, Amar Deep; Nedea, Silvia; Zondag, Herbert; Rindt, Camilo; Smeulders, David

    2016-04-21

    Salt hydrates store solar energy in chemical form via a reversible dehydration-hydration reaction. However, as a side reaction to dehydration, hydrolysis (HCl formation) may occur in chloride based salt hydrates (specially in MgCl2 hydrates), affecting the durability of the storage system. The mixture of CaCl2 and MgCl2 hydrates has been shown experimentally to have exceptional cycle stability and improved kinetics. However, the optimal operating conditions for the mixture are unknown. To understand the appropriate balance between dehydration and hydrolysis kinetics in the mixtures, it is essential to gain in-depth insight into the mixture components. We present a GGA-DFT level study to investigate the various gaseous structures of CaCl2 hydrates and to understand the relative stability of their conformers. The hydration strength and relative stability of conformers are dominated by electrostatic interactions. A wide network of intramolecular homonuclear and heteronuclear hydrogen bonds is observed in CaCl2 hydrates. Equilibrium product concentrations are obtained during dehydration and hydrolysis reactions under various temperature and pressure conditions. The trend of the dehydration curve with temperature in CaCl2 hydrates is similar to the experiments. Comparing these results to those of MgCl2 hydrates, we find that CaCl2 hydrates are more resistant towards hydrolysis in the temperature range of 273-800 K. Specifically, the present study reveals that the onset temperatures of HCl formation, a crucial design parameter for MgCl2 hydrates, are lower than for CaCl2 hydrates except for the mono-hydrate.

  8. Comparative TPR and TPD Studies of Cu and Ca Promotion on Fe-Zn- and Fe-Zn-Zr-Based Fischer-Tropsch Catalysts

    Directory of Open Access Journals (Sweden)

    James Olusola O.

    2015-03-01

    Full Text Available The present study demonstrates the effect of zirconium promotion on Fe-Zn-based catalysts to boost the active sites of Fischer-Tropsch (FT catalysts. The catalysts are also promoted by Cu and Ca and the active sites are examined using Temperature-Programmed Reduction (TPR with H2 and CO and Temperature-Programmed Desorption (TPD with NH3 and CO2. The results are presented as a comparative study between Fe-Zn- and Fe-Zn-Zr-based catalysts. The results show that addition of Zr to Fe-Zn catalysts increases the availability and dispersion of the precursor to the active sites and promotion with Cu and Ca independently and synergistically enhances reduction of Fe-Zn-Zr-based catalysts. The presence of Ca promotes carburisation, while Cu inhibits carburisation. The impact of the Ca and Cu on the surface acidity/basicity is governed by the nature of the interaction between the phases in the catalysts. The extent of reduction reflects the availability and dispersion of the precursor to the active phase, while the extent of carburisation will impact on the selectivity of the catalysts.

  9. Sensitization by extracellular Ca(2+) of rat P2X(5) receptor and its pharmacological properties compared with rat P2X(1).

    Science.gov (United States)

    Wildman, Scott S; Brown, Sean G; Rahman, Mary; Noel, Carole A; Churchill, Linda; Burnstock, Geoffrey; Unwin, Robert J; King, Brian F

    2002-10-01

    The recombinant rat P2X(5) (rP2X(5)) receptor, a poorly understood ATP-gated ion channel, was studied under voltage-clamp conditions and compared with the better understood homomeric rP2X(1) receptor with which it may coexist in vivo. Expressed in defolliculated Xenopus laevis oocytes, rP2X(5) responded to ATP with slowly desensitizing inward currents that, for successive responses, ran down in the presence of extracellular Ca(2+) (1.8 mM). Replacement of Ca(2+) with either Ba(2+) or Mg(2+) prevented rundown, although agonist responses were very small, whereas reintroduction of Ca(2+) for short periods of time ( 2',3'-O-(2,4,6-trinitrophenyl)ATP (TNP-ATP) > suramin > reactive blue 2 (RB-2) > diinosine pentaphosphate (Ip(5)I). In contrast, the potency order at rP2X(1) was TNP-ATP = Ip(5)I > PPADS > suramin = RB-2. Thus, the Ca(2+)-sensitized homomeric rP2X(5) receptor is similar in agonist profile to homomeric rP2X(1)-although it can be distinguished from the latter by GTP agonism, antagonist profile, and the modulatory effects of H(+) and Zn(2+) ions.

  10. Optimization of methylene blue using Ca(2+) and Zn(2+) bio-polymer hydrogel beads: A comparative study.

    Science.gov (United States)

    Kumar, M; Tamilarasan, R; Arthanareeswaran, G; Ismail, A F

    2015-11-01

    Recently noted that the methylene blue cause severe central nervous system toxicity. It is essential to optimize the methylene blue from aqueous environment. In this study, a comparison of an optimization of methylene blue was investigated by using modified Ca(2+) and Zn(2+) bio-polymer hydrogel beads. A batch mode study was conducted using various parameters like time, dye concentration, bio-polymer dose, pH and process temperature. The isotherms, kinetics, diffusion and thermodynamic studies were performed for feasibility of the optimization process. Freundlich and Langmuir isotherm equations were used for the prediction of isotherm parameters and correlated with dimensionless separation factor (RL). Pseudo-first order and pseudo-second order Lagegren's kinetic equations were used for the correlation of kinetic parameters. Intraparticle diffusion model was employed for diffusion of the optimization process. The Fourier Transform Infrared Spectroscopy (FTIR) shows different absorbent peaks of Ca(2+) and Zn(2+) beads and the morphology of the bio-polymer material analyzed with Scanning Electron Microscope (SEM). The TG & DTA studies show that good thermal stability with less humidity without production of any non-degraded products. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. COMPARATION OF METHODS FOR CHEMICAL ANALYSIS OF K, Ca, Mg e Al, IN MATÉ TEA TREE (Ilex paraguariensis St. Hil.

    Directory of Open Access Journals (Sweden)

    Charles Carneiro

    2006-06-01

    Full Text Available This study was carried out in order to test five chemical methods for leaf analysis and their interrelationships in the analysis of K, Ca, Mg and Al in tea leaves. The samples were collected in a liming experiment, with different base saturation levels, laid out in the field with planted erva-mate (Ilex paraguariensis St. Hil., located at Pinhais County, Paraná State. The evaluated methods were as follows: Wet digestion with nitro-perchloric acid, dry ashing in porcelain crucibles, dry ashing in platinum crucibles, wet extraction (non digestion with 1 mol/L HCl and wet extraction (non digestion with 1 mol/L HCl+d (d=further 1:3 dilution of the extract. In the laboratory, the samples were ordered according a split plot design, being factor A, the five tested methodologies and as factor B, the different base saturation levels of the field. All tested variables presented statistical significance (P0,01 for variation source and methods. High solubilizations were achieved for most of the tested elements with the nitro-perchloric, dry ashing in porcelain crucibles, and both HCl wet extractions methods. The non digestion methods with HCl showed to be highly promising. High significance was observed for the correlation among methods for K, Mg and Al. Ca showed the poorest correlations among methods.

  12. Protective and inhibitory effects of various types of amphipols on the Ca2+-ATPase from sarcoplasmic reticulum: a comparative study.

    Science.gov (United States)

    Picard, Martin; Dahmane, Tassadite; Garrigos, Manuel; Gauron, Carole; Giusti, Fabrice; le Maire, Marc; Popot, Jean-Luc; Champeil, Philippe

    2006-02-14

    Amphipols are amphipathic polymers designed to replace or supplement detergents in membrane protein solution studies. Previous work has suggested both advantages and disadvantages to the use of a polyacrylate-based amphipol, A8-35, for studying the sarcoplasmic reticulum Ca2+-ATPase (SERCA1a). We investigated this issue further using a set of four amphipols with different chemical structures. Previous size exclusion chromatography experiments had shown that A8-35 and SERCA1a/A8-35 complexes aggregate under certain conditions. We show here that aggregation can be prevented by omitting calcium from buffers or by using a sulfonated version of A8-35. A8-35 had previously been shown to protect Ca2+-ATPase from irreversible denaturation, while inhibiting its activity in a reversible manner. We show here that the other three amphipols tested also display these properties and that all four amphipols slow down backward calcium dissociation from the nonphosphorylated solubilized enzyme, a priori an unrelated step. As this calcium dissociation involves the opening up of the bundle of transmembrane ATPase segments, the slowing of this process may indicate that multipoint attachment of the polymers to the hydrophobic transmembrane surface damps protein dynamics ("Gulliver" effect). Damping might be the reason why amphipols also simultaneously protect membrane proteins against irreversible denaturation and may inhibit the activity of those of them that display large rearrangements of their transmembrane surface during their catalytic cycle.

  13. Limited Ca2+ and PKA-pathway dependent neurogenic differentiation of human adult mesenchymal stem cells as compared to fetal neuronal stem cells.

    Science.gov (United States)

    Lepski, Guilherme; Jannes, Cinthia Elim; Maciaczyk, Jaroslaw; Papazoglou, Anna; Mehlhorn, Alexander T; Kaiser, Stefan; Teixeira, Manoel Jacobsen; Marie, Suely K N; Bischofberger, Josef; Nikkhah, Guido

    2010-01-15

    The ability of mesenchymal stem cells to generate functional neurons in culture is still a matter of controversy. In order to assess this issue, we performed a functional comparison between neuronal differentiation of human MSCs and fetal-derived neural stem cells (NSCs) based on morphological, immunocytochemical, and electrophysiological criteria. Furthermore, possible biochemical mechanisms involved in this process were presented. NF200 immunostaining was used to quantify the yield of differentiated cells after exposure to cAMP. The addition of a PKA inhibitor and Ca(2+) blockers to the differentiation medium significantly reduced the yield of differentiated cells. Activation of CREB was also observed on MSCs during maturation. Na(+)-, K(+)-, and Ca(2+)-voltage-dependent currents were recorded from MSCs-derived cells. In contrast, significantly larger Na(+) currents, firing activity, and spontaneous synaptic currents were recorded from NSCs. Our results indicate that the initial neuronal differentiation of MSCs is induced by cAMP and seems to be dependent upon Ca(2+) and the PKA pathway. However, compared to fetal neural stem cells, adult mesenchymal counterparts are limited in their neurogenic potential. Despite the similar yield of neuronal cells, NSCs achieved a more mature functional state. Description of the underlying mechanisms that govern MSCs' differentiation toward a stable neuronal phenotype and their limitations provides a unique opportunity to enhance our understanding of stem cell plasticity.

  14. Comparative characterization of two intracellular Ca²⁺-release channels from the red flour beetle, Tribolium castaneum.

    Science.gov (United States)

    Liu, Yaping; Li, Chengjun; Gao, Jingkun; Wang, Wenlong; Huang, Li; Guo, Xuezhu; Li, Bin; Wang, Jianjun

    2014-10-21

    Ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (IP3Rs) are members of a family of tetrameric intracellular Ca(2+)-release channels (CRCs). While it is well known in mammals that RyRs and IP3Rs modulate multiple physiological processes, the roles of these two CRCs in the development and physiology of insects remain poorly understood. In this study, we cloned and functionally characterized RyR and IP3R cDNAs (named TcRyR and TcIP3R) from the red flour beetle, Tribolium castaneum. The composite TcRyR gene contains an ORF of 15,285 bp encoding a protein of 5,094 amino acid residues. The TcIP3R contains an 8,175 bp ORF encoding a protein of 2,724 amino acids. Expression analysis of TcRyR and TcIP3R revealed significant differences in mRNA expression levels among T. castaneum during different developmental stages. When the transcript levels of TcRyR were suppressed by RNA interference (RNAi), an abnormal folding of the adult hind wings was observed, while the RNAi-mediated knockdown of TcIP3R resulted in defective larval-pupal and pupal-adult metamorphosis. These results suggested that TcRyR is required for muscle excitation-contraction (E-C) coupling in T. castaneum, and that calcium release via IP3R might play an important role in regulating ecdysone synthesis and release during molting and metamorphosis in insects.

  15. An exceptionally strengthened East Asian summer monsoon event between 19.9 and 17.1 ka BP recorded in a Hulu stalagmite

    Institute of Scientific and Technical Information of China (English)

    L.; R.; EDWARDS

    2009-01-01

    A stalagmite-based isotope record (No. H82) from Nanjing Hulu Cave, spanning from 16.5 to 10.3 ka BP, provided strong evidence for a coherence relation between the East Asian summer monsoon (EASM) and the North Atlantic climates on millennial time scales. Here we extend the high-resolution δ 18O time series back to 22.1 ka BP with additional 7 230Th dates and 573 stable isotope measurements on the lower part of that sample. The new record with a decadal resolution, piecing together with the previous data, provides a detailed, complete Last Glacial Maximum (LGM)/deglacial history of the EASM. Two centennial-scale weak monsoon events are detected within the analogue H1 event, and can be corre- lated to corresponding Greenland temperature shifts. This suggests a rapid re-organization of atmos- pheric and oceanic circulations during the ice-rafted debris (IRD) event in North Atlantic. A strength- ened EASM event spanning from 19.9 to 17.1 ka BP, firstly reported here, reaches on average a half of the monsoon intensity of B?lling warming with its peak close to the full level. Taking all available evi- dence from continental and oceanic sediments into consideration, we suggest that a forcing mecha- nism behind the event would be a positive feedback of the tropical Pacific Super-ENSO cycles in re- sponse to precessional changes in solar irradiation.

  16. An exceptionally strensthened East Asian summer monsoon event between 19.9 and 1 7.1 ka BP recorded in a Hulu stalagmite

    Institute of Scientific and Technical Information of China (English)

    WU JiangYing; WANG YongJin; CHENG Hai; L.R.EDWARDS

    2009-01-01

    A stalagmite-based isotope record (No.H82)from Nanjing Hulu Cave,spanning from 16.5 to 10.3 ka BP,provided strong evidence for a coherence relation between the East Asian summer monsoon (EASM) and the North Atlantic climates on millennial time scales.Here we extend the high-resolution δ18O time series back to 22.1 ka BP with additional 7 230 Th dates and 573 stable isotope measurements on the lower part of that sample.The new record with a decadal resolution,piecing together with the previous data,provides a detailed,complete Last Glacial Maximum (LGM)/deglacial history of the EASM.Two centennial-scale weak monsoon events are detected within the analogue H1 event,and can be correlated to corresponding Greenland temperature shifts.This suggests a rapid re-organization of atmospheric and oceanic circulations during the ice-rafted debris (IRD) event in North Atlantic.A strengthened EASM event spanning from 19.9 to 17.1 ka BP,firstly reported here,reaches on average a half of the monsoon intensity of B(Φ)iling warming with its peak close to the full level.Taking all available evidence from continental and oceanic sediments into consideration,we suggest that a forcing mechanism behind the event would be a positive feedback of the tropical Pacific Super-ENSO cycles in response to precessional changes in solar irradiation.

  17. Targeting the American market for medicines, ca. 1950s-1970s: ICI and Rhône-Poulenc compared.

    Science.gov (United States)

    Quirke, Viviane

    2014-01-01

    The forces that have shaped American medicine include a wide set of interrelated changes, among them the changing research, development, and marketing practices of the pharmaceutical industry. This article compares the research and development (R&D) and marketing strategies of the British group Imperial Chemical Industries (ICI, whose Pharmaceutical Division was spun off and merged with the Swedish company Astra to form AstraZeneca) and its French counterpart Rhône-Poulenc (now part of Sanofi-Aventis) in dealing with the American medical market. It examines how, in the process, the relationship between R&D and marketing was altered, and the firms themselves were transformed. The article also questions the extent to which their approaches to this market, one of the most significant markets for drugs in general, and for anticancer drugs in particular, became standardized in the period of "scientific marketing."

  18. Comparative study of the absorption spectrum of Li 2CaSiO 4:Cr 4+: First-principles fully relativistic and crystal field calculations

    Science.gov (United States)

    Brik, M. G.; Ogasawara, K.

    2007-11-01

    Systematic analysis of the energy level scheme and ground state absorption of the Cr4+ ion in Li2CaSiO4 crystal was performed using the exchange charge model of the crystal field [B.Z. Malkin, in: A.A. Kaplyanskii, B.M. Macfarlane (Eds.), Spectroscopy of Solids Containing Rare-earth Ions, North-Holland, Amsterdam, 1987, pp. 33-50] and recently developed first-principles approach to the analysis of the absorption spectra of impurity ions in crystals based on the discrete variational multielectron (DVME) method [K. Ogasawara, T. Iwata, Y. Koyama, T. Ishii, I. Tanaka, H. Adachi, Phys. Rev. B 64 (2001) 115413]. Using the former method, the values of parameters of crystal field acting on the Cr4+ ion valence electrons were calculated using the Li2CaSiO4 crystal structure data. Energy levels of the Cr4+ ion obtained after diagonalizing the crystal field Hamiltonian are in good agreement with those obtained from the experimental spectra. The latter method is based on the numerical solution of the Dirac equation; therefore, all relativistic effects are automatically considered. As a result, energy level scheme of Cr4+ and its absorption spectra in both polarizations were calculated, assigned and compared with experimental data; energy of the lowest charge transfer transition was evaluated and compared with theoretical predictions for the CrO44- complex available in the literature. The main features of the experimental spectra shape are reproduced well by the calculations. By performing analysis of the molecular orbitals (MO) population, it was shown that the covalent effects play an important role in formation of the spectral properties of Cr4+ ion in the considered crystal.

  19. Impaired presynaptic cytosolic and mitochondrial calcium dynamics in aged compared to young adult hippocampal CA1 synapses ameliorated by calcium chelation.

    Science.gov (United States)

    Tonkikh, A A; Carlen, P L

    2009-04-10

    Impaired regulation of presynaptic intracellular calcium is thought to adversely affect synaptic plasticity and cognition in the aged brain. We studied presynaptic cytosolic and mitochondrial calcium (Ca) dynamics using axonally loaded Calcium Green-AM and Rhod-2 AM fluorescence respectively in young (2-3 months) and aged (23-26 months) CA3 to CA1 Schaffer collateral excitatory synapses in hippocampal brain slices from Fisher 344 rats. After a tetanus (100 Hz, 200 ms), the presynaptic cytosolic Ca peaked at approximately 10 s in the young and approximately 12 s in the aged synapses. Administration of the membrane permeant Ca chelator, bis (O-aminophenoxy)-ethane-N,N,N,N-tetraacetic acid (BAPTA-AM), significantly attenuated the Ca response in the aged slices, but not in the young slices. The presynaptic mitochondrial Ca signal was much slower, peaking at approximately 90 s in both young and aged synapses, returning to baseline by 300 s. BAPTA-AM significantly attenuated the mitochondrial calcium signal only in the young synapses. Uncoupling mitochondrial respiration by carbonyl cyanide m-chlorophenylhydrazone (CCCP) application evoked a massive intracellular cytosolic Ca increase and a significant drop of mitochondrial Ca, especially in aged slices wherein the cytosolic Ca signal disappeared after approximately 150 s of washout and the mitochondrial Ca signal disappeared after 25 s of washout. These signals were preserved in aged slices by BAPTA-AM. Five minutes of oxygen glucose deprivation (OGD) was associated with a significant increase in cytosolic Ca in both young and aged synapses, which was irreversible in the aged synapses. These responses were significantly attenuated by BAPTA-AM in both the young and aged synapses. These results support the hypothesis that increasing intracellular calcium neuronal buffering in aged rats ameliorates age-related impaired presynaptic Ca regulation.

  20. Comparative angle-resolved photoemission spectroscopy study of CaRuO3 and SrRuO3 thin films: Pronounced spectral weight transfer and possible precursor of lower Hubbard band

    Science.gov (United States)

    Yang, H. F.; Fan, C. C.; Liu, Z. T.; Yao, Q.; Li, M. Y.; Liu, J. S.; Jiang, M. H.; Shen, D. W.

    2016-09-01

    In the prototypical 4 d system (Sr ,Ca ) RuO3 , the degree and origin of electron correlations, and how they correlate with physical properties, still remain elusive, though extensive studies have been performed. In this work we present a comparative electronic structure study of high-quality epitaxial CaRuO3 and SrRuO3 thin films, by means of reactive molecular beam epitaxy and in situ angle-resolved photoemission spectroscopy. We found that while SrRuO3 possesses sharp features signaling the Fermi liquid state, the isostructural CaRuO3 exhibits broad features and its spectral weight is markedly transferred from the Fermi level to -1.2 eV forming a "hump" structure which resembles the Mott-Hubbard system (Sr ,Ca ) VO3 . We suggest that this hump is the precursor of the lower Hubbard band, and the U /W (U and W represent the on-site Coulomb interactions and bandwidth, respectively) of our CaRuO3 thin film is much larger than that of SrRuO3. In addition, we discuss the origin of electron correlations as well as the ferromagnetism in SrRuO3 which is absent in CaRuO3. Our findings put constraints on future studies, and also show that perovskite ruthenates are indeed an experimentally tunable system for the study of electron correlations.

  1. High-Tc Superconductivity and Raman Scattering Study of the phonon properties of electron doped (transition metal, rare-earth) - Oxygen-Free CaFeAsF and compared with RFeAsO system

    Science.gov (United States)

    Sasmal, Kalyan; Hadjiev, Viktor; Chu, C. W.(Paul)

    Quaternary CaFeAsF has ZrCuSiAs-type structure,(RO)δ+ layer in RFeAsO replaced by (CaF)δ+ layer,with tetragonal (P4/nmm)-orthorhombic (Cmma) phase transition at 134K,while magnetic order,SDW sets in at 114K. Partial replacement of Fe with Co/Ni is direct electron doping to (FeAs)δ+ layer.Tc ~15K in CaFe0.9Ni0.1AsF.Substitution of rare earth metal for alkaline earth metal suppresses anomaly in resistivity & induces superconductivity.Tc ~52K in Ca0.5Pr0.5FeAsF.Characterized by resistivity, susceptibility,XRD & EDX-SEM.Upper critical field estimated from magneto resistance.Bulk superconductivity proved by DC magnetization. Hall coefficient RH revealed hole-like charge carriers in parent compound CaFeAsF, while electron-type (RH in normal state is -Ve) for Ca0.5Pr0.5FeAsF.Evolution of Raman active phonons of Ca1-xPrxFeAsF measured with polarized Raman spectroscopy at room temperature from absurfaces of impurity-free microcrystals.Spectra exhibit sharp phonon lines on very weak electronic scattering background.Frequency and symmetry of Raman phonons involving out-of-plane atomic vibrations are found at 162.5 cm-1 (A1 g, Pr), 201 cm-1 (A1 g, As), 215.5 cm-1 (B1 g, Fe), 265 cm-1 (Eg, Fe) and 334 cm-1 (B1 g, F) for Ca0.5Pr0.5FeAsF.Observations are compared with RFeAsO unconventional superconductors also possibly related to magnetic fluctuations

  2. Comparative studies on troponin, a Ca²⁺-dependent regulator of muscle contraction, in striated and smooth muscles of protochordates.

    Science.gov (United States)

    Obinata, Takashi; Sato, Naruki

    2012-01-01

    Troponin is well known as a Ca(2+)-dependent regulator of striated muscle contraction and it has been generally accepted that troponin functions as an inhibitor of muscle contraction or actin-myosin interaction at low Ca(2+) concentrations, and Ca(2+) at higher concentrations removes the inhibitory action of troponin. Recently, however, troponin became detectable in non-striated muscles of several invertebrates and in addition, unique troponin that functions as a Ca(2+)-dependent activator of muscle contraction has been detected in protochordate animals, although troponin in vertebrate striated muscle is known as an inhibitor of the contraction in the absence of a Ca(2+). Further studies on troponin in invertebrate muscle, especially in non-striated muscle, would provide new insight into the evolution of regulatory systems for muscle contraction and diverse function of troponin and related proteins. The methodology used for preparation and characterization of functional properties of protochordate striated and smooth muscles will be helpful for further studies of troponin in other invertebrate animals.

  3. Comparative effects of technical toxaphene, 2,5-dichloro-3-biphenylol and octabromodiphenylether on cell viability, [Ca2+]i levels and membrane fluidity in mouse thymocytes.

    Science.gov (United States)

    Sandal, Suleyman; Yilmaz, Bayram; Chen, Chang-Hwei; Carpenter, David O

    2004-08-01

    Flow cytometric studies of mouse thymocytes show that technical toxaphene (10-20 ppm) and 2,5-dichloro-3-biphenylol (PCB 9-OH) (5-10 ppm) kill cells and cause an increase in intracellular calcium concentration, [Ca2+]i, whereas commercial octabromodiphenylether (OBDE) has no effect. The cell death is not a result of the rise of [Ca2+]i, since the divalent cation ionophore, ionomycin, causes a large elevation in [Ca2+]i without cell death. We have studied effects of these compounds on membrane fluorescence polarization, a measure of membrane fluidity, using 1,6-diphenyl-1,3,5-hexatriene (DPH). We find that toxaphene causes a decrease in membrane fluidity in the concentration range associated with cell death, whereas PCB 9-OH causes an increase in fluidity and OBDE has no effect. These observations suggest that alterations of membrane fluidity of thymocytes, whether it be an increase or decrease, can cause cytotoxicity.

  4. Comparative study of the immunogenicity in mice and monkeys of an inactivated CA16 vaccine made from a human diploid cell line.

    Science.gov (United States)

    Yang, Erxia; Cheng, Chen; Zhang, Ying; Wang, Jingjing; Che, Yanchun; Pu, Jing; Dong, Chenghong; Liu, Longding; He, Zhanlong; Lu, Shuaiyao; Zhao, Yuan; Jiang, Li; Liao, Yun; Shao, Congwen; Li, Qihan

    2014-01-01

    The coxsackie A16 virus (CA16), along with enterovirus 71 (EV71), is a primary pathogen that causes hand, foot, and mouth disease (HFMD). To control HFMD, CA16, and EV71 vaccines are needed. In this study, an experimental inactivated CA16 vaccine was prepared using human diploid cells, and the vaccine's immunogenicity was analyzed in mice and rhesus monkeys. The results showed that the neutralizing antibody was developed in a dose-dependent manner, and was sustained for 70 days with an average GMT (geometric mean titer) level of 80 to 90 in immunized mouse and for 56 days with GMT of higher than 300 in monkeys. The neutralizing antibody had a cross-neutralizing activity against different viral strains (genotype A and B), and the specific IFN-γ-secreting cell response was activated by these virus strains in an ELISPOT assay. This study provides evidence for the potential use of inactivated CA16 as a candidate for use in vaccines.

  5. Evidence for pre-Cretaceous history and partial Neogene (19-9 Ma) reequilibration in the Karakorum (NW Himalayan Syntaxis) from 40Ar- 39Ar amphibole dating

    Science.gov (United States)

    Rolland, Yann; Villa, Igor M.; Guillot, Stéphane; Mahéo, Gweltaz; Pêcher, Arnaud

    2006-09-01

    Amphiboles and a biotite from amphibolites and amphibolitic gneisses of the Karakorum Metamorphic Complex (KMC, NW Himalaya), were dated using the 40Ar/ 39Ar method. Isotope correlations were compared to electron-microprobe analyses. Both Al IV and Al VI contents of amphibole increase from the south near the Shyok Suture Zone to the Dassu-Askole Area in the north, with an increase in metamorphic grade (from anchizone to upper amphibolite facies). In the lower metamorphic zone, discordant age spectra were obtained. They are related to epidote-amphibolite overgrowth of amphibole rims on older (Precambrian to Mesozoic) magmatic cores. In the Shyok Suture Zone Ar/Ar ages of 38-62 Ma are contemporaneous with the emplacement of the Ladakh Batholith granodiorites, while middle Cretaceous magmatic Ar/Ar ages (˜ 120 Ma) are locally preserved in tschermakite relics. In the Southern Karakorum basement, a minimum Ar/Ar age of 651 Ma was preserved, while an age of 208.5±2 Ma was preserved in Panjal Trap-like diorites. At the margin of the domes zone, more recent metamorphism resulted in mineral growth at 20-5 Ma. In the domes zone, amphibole Ar/Ar ages of 17 Ma (Askole) and bimodal age spectra of 15-17 and 9-13 Ma (Dassu) extend towards the east the zone of Neogene amphibolite to granulite facies metamorphism known in the Nanga Parbat Syntaxis.

  6. Comparative Study Between GGA and LDA Approximation Using First- Principles Calculations of Structural, Electronic, Optical and Vibrational Properties of CaTiO3 Crystal

    Science.gov (United States)

    Medeiros, Subenia; Araujo, Maeva

    2015-03-01

    The structural, electronic, vibrational, and optical properties of perovskite CaTiO3 in the cubic, orthorhombic, and tetragonal phase are calculated in the framework of density functional theory (DFT) with different exchange-correlation potentials by CASTEP package. The calculated band structure shows an indirect band gap of 1.88 eV at the Γ-R points in the Brillouin zone to the cubic structure, a direct band gap of 2.41 eV at the Γ- Γ points to the orthorhombic structure, and an indirect band gap of 2.31 eV at theM - Γ points to the tetragonal phase. It is still known that the CaTiO3 has a static dielectric constant that extrapolates to a value greater than 300 at zero temperature, and the dielectric response is dominated by low frequency (ν ~ 90cm-1) polar optical modes in which cation motion opposes oxygen motion. Our calculated lattice parameters, elastic constants, optical properties, and vibrational frequencies are found to be in good agreement with the available theoretical and experimental values. The results for the effective mass in the electron and hole carriers are also presented in this work.

  7. A comparative study based on the first principles calculations of ATiO3 ( A = Ba, Ca, Pb and Sr) perovskite structure

    Science.gov (United States)

    Kamruzzaman, M.; Helal, M. A.; Ara, I. E.; Farid Ul Islam, A. K. M.; Rahaman, M. M.

    2016-10-01

    Structural, electronic, elastic, thermodynamic, vibrational and optical properties of the cubic phase of ATiO3 ( A = Ba, Ca, Pb and Sr) crystals have been carried out based on the density functional theory (DFT). The calculated equilibrium lattice parameters, band structures, elastic constants and the elastic moduli of ATiO3 are in good agreement with the theoretical and experimental results. The ferroelectric phenomenon of the crystals has been analyzed based on the nature of their phonon spectra. The phonon frequencies and the Born effective charges have been calculated to elucidate the ferroelectric instability of the cubic phase of ATiO3 by calculating the interatomic forces for several small displacements consistent with the symmetry of modes.

  8. Comparative study of the magnetic and electronic properties of Bi{sub 0.75}A{sub 0.25}MnO{sub 3}(x=28) with A=Ca and Sr

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Munoz, J.L. [Instituto de Ciencia de Materiales de Barcelona, C.S.I.C., Campus Universitari de Bellaterra, E-08193, Bellaterra, Barcelona (Spain)]. E-mail: garcia.munoz@icmab.es; Frontera, C. [Instituto de Ciencia de Materiales de Barcelona, C.S.I.C., Campus Universitari de Bellaterra, E-08193, Bellaterra, Barcelona (Spain); Beran, P. [Instituto de Ciencia de Materiales de Barcelona, C.S.I.C., Campus Universitari de Bellaterra, E-08193, Bellaterra, Barcelona (Spain); Bellido, N. [Instituto de Ciencia de Materiales de Barcelona, C.S.I.C., Campus Universitari de Bellaterra, E-08193, Bellaterra, Barcelona (Spain): Laboratoire CRISMAT, UMR CNRS/ISMRA, F-14050 Caen Cedex (France); Capdevila, X.G. [Dep. d' Enginyeria Quimica i Metal.lurgia, Universitat de Barcelona, Facultat de Quimica, E-08028 Barcelona (Spain); Calleja, A. [Dep. d' Enginyeria Quimica i Metal.lurgia, Universitat de Barcelona, Facultat de Quimica, E-08028 Barcelona (Spain); Lord, J.S. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom); Ritter, C. [Institut Laue Langevin, BP 156, F-38042 Grenoble Cedex 9 (France)

    2006-03-31

    We present a comparative investigation of the Bi manganites with commensurate composition x=14: Bi{sub 0.75}Sr{sub 0.25}MnO{sub 3} and Bi{sub 0.75}Ca{sub 0.25}MnO{sub 3}. {mu}SR and diffraction data confirm different structural, magnetic and electronic transitions in the two compounds. The robust charge-order phase detected with Sr do not occur in Bi{sub 0.75}Ca{sub 0.25}MnO{sub 3}, which present inhomogeneous magnetism and short-range charge order. In both compounds the application of magnetic fields produces a continuous progressive canting of the moments, visible even for relatively small fields ({mu}{sub 0}H-bar 1T)

  9. A comparative study on metamagnetic transitions in half-doped Pr 0.45La 0.05Ca 0.5MnO 3 and Pr 0.45Gd 0.05Ca 0.5MnO 3 manganites

    Science.gov (United States)

    Mavani, K. R.; Paulose, P. L.

    2006-05-01

    Half-doped Pr 0.5Ca 0.5MnO 3 is an ABO 3-type, charge-ordered antiferromagnetic system with a negligible A-site cation size disorder ( σ2). The A-site substitution by larger or smaller ions than Pr 3+/Ca 2+ in this system increases σ2. We have studied and compared the σ2 and cation size effects on metamagnetic transitions by substituting 5 atomic percentage of isovalent larger ion La 3+ or smaller ion Gd 3+ at A-site in this system. We find that the La substitution induces successive sharp step-like metamagnetic transitions at low temperature, in contrast to a smooth metamagnetic transition induced by Gd substitution.

  10. A comparative study of K-rich and Na/Ca-rich feldspar ice-nucleating particles in a nanoliter droplet freezing assay

    Science.gov (United States)

    Peckhaus, Andreas; Kiselev, Alexei; Hiron, Thibault; Ebert, Martin; Leisner, Thomas

    2016-09-01

    A recently designed droplet freezing assay was used to study the freezing of up to 1500 identical 0.2 nL water droplets containing suspensions of one Na/Ca-rich feldspar and three K-rich and one Na/Ca-rich feldspar particles. Three types of experiments have been conducted: cooling ramp, isothermal freezing at a constant temperature, and freeze-thaw cycles. The observed freezing behavior has been interpreted with the help of a model based on the classical nucleation theory (soccer ball model (SBM); Niedermeier et al., 2015). By applying the model to the different freezing experiments conducted with the same ice-nucleating material, the unique sets of model parameters for specific feldspar suspensions could be derived. The SBM was shown to adequately describe the observed cooling rate dependence, the ice-nucleating active sites (INAS) surface density ns(T) in a wide temperature range, and the shift of the freezing curves towards lower temperature with dilution. Moreover, the SBM was capable of reproducing the variation of INAS surface density ns(T) with concentration of ice-nucleating particles in the suspension droplets and correctly predicting the leveling-off of ns(T) at low temperature. The freeze-thaw experiments have clearly shown that the heterogeneous freezing induced even by very active ice-nucleating species still possesses a stochastic nature, with the degree of randomness increasing towards homogeneous nucleation. A population of the high-temperature INAS has been identified in one of the K-rich feldspar samples. The freezing of 0.8 wt % suspension droplets of this particular feldspar was observed already at -5 °C. These high-temperature active sites could be deactivated by treating the sample with hydrogen peroxide but survived heating up to 90 °C. Given a high mass concentration of these high-temperature active sites (2.9 × 108 g-1) and a very low value of contact angle (0.56 rad) the possibility of biological contamination of the sample was

  11. Comparing Productivity in the Netherlands, France, UK and US, ca. 1910 : A new PPP benchmark and its implications for changing economic leadership

    NARCIS (Netherlands)

    Frankema, Ewout; Smits, Jan-Pieter; Woltjer, P.

    2010-01-01

    This paper presents a new benchmark of fisher weighted sector PPPs for agriculture, mining and five manufacturing branches in the US, UK, France and the Netherlands around 1910. The PPPs are constructed according to an industry-of-origin approach in order to assess comparative levels of labour

  12. Ca(2+) -complex stability of GAPAGPLIVPY peptide in gas and aqueous phase, investigated by affinity capillary electrophoresis and molecular dynamics simulations and compared to mass spectrometric results.

    Science.gov (United States)

    Nachbar, Markus; El Deeb, Sami; Mozafari, Mona; Alhazmi, Hassan A; Preu, Lutz; Redweik, Sabine; Lehmann, Wolf Dieter; Wätzig, Hermann

    2016-03-01

    Strong, sequence-specific gas-phase bindings between proline-rich peptides and alkaline earth metal ions in nanoESI-MS experiments were reported by Lehmann et al. (Rapid Commun. Mass Spectrom. 2006, 20, 2404-2410), however its relevance for physiological-like aqueous phase is uncertain. Therefore, the complexes should also be studied in aqueous solution and the relevance of the MS method for binding studies be evaluated. A mobility shift ACE method was used for determining the binding between the small peptide GAPAGPLIVPY and various metal ions in aqueous solution. The findings were compared to the MS results and further explained using computational methods. While the MS data showed a strong alkaline earth ion binding, the ACE results showed nonsignificant binding. The proposed vacuum state complex also decomposed during a molecular dynamic simulation in aqueous solution. This study shows that the formed stable peptide-metal ion adducts in the gas phase by ESI-MS does not imply the existence of analogous adducts in the aqueous phase. Comparing peptide-metal ion interaction under the gaseous MS and aqueous ACE conditions showed huge difference in binding behavior.

  13. CaCu{sub 3}Ti{sub 4}O{sub 12} thin films on conductive oxide electrode: A comparative study between chemical and physical vapor deposition routes

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, Maria R.; Malandrino, Graziella [Dipartimento di Scienze Chimiche, Universita di Catania, and INSTM, UdR Catania, Viale A. Doria 6, 95125 Catania (Italy); Bongiorno, Corrado [Istituto per la Microelettronica e Microsistemi, IMM-CNR, Strada VIII 5, 95121 Catania (Italy); Toro, Roberta G. [Istituto per lo Studio dei Materiali Nanostrutturati, ISMN-CNR, Via dei Taurini, 19, 00185 Roma (Italy); Fiorenza, Patrick [Istituto per la Microelettronica e Microsistemi, IMM-CNR, Strada VIII 5, 95121 Catania (Italy); Bodeux, Romain [Laboratoire LEMA, UMR 6157 CNRS/CEA, Universite F. Rabelais, Parc de Grandmont, 37200 Tours (France); STMicroelectronics, R and D, Rue Pierre et Marie Curie, 37000 Tours (France); Wolfman, Jerome; Gervais, Monique; Lambert, Cecile Autret; Gervais, Francois [Laboratoire LEMA, UMR 6157 CNRS/CEA, Universite F. Rabelais, Parc de Grandmont, 37200 Tours (France); Lo Nigro, Raffaella, E-mail: raffaella.lonigro@imm.cnr.it [Istituto per la Microelettronica e Microsistemi, IMM-CNR, Strada VIII 5, 95121 Catania (Italy)

    2012-04-16

    Highlights: Black-Right-Pointing-Pointer Dielectrics growth and characterization is one of the most hot topics of materials science and microelectronics. Black-Right-Pointing-Pointer CaCu{sub 3}Ti{sub 4}O{sub 12} perovskite, recently, demonstrated to possess peculiar dielectric properties (Science, 2001, 293, 673-676). Black-Right-Pointing-Pointer To date no deep discussion on the growth processes, properties and perspective of CCTO thin films has been proposed. Black-Right-Pointing-Pointer Our paper is an effective example of interdisciplinarity, since the comparison between PLD and MOCVD has been addressed. Black-Right-Pointing-Pointer Great attention has been paid to CaCu{sub 3}Ti{sub 4}O{sub 12} film/substrate interfaces since dielectric properties are strongly affected. - Abstract: Metal Organic Chemical Vapor Deposition (MOCVD) and Pulsed Laser Deposition (PLD) techniques have been used for the growth of CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO) thin films on La{sub 0.9}Sr{sub 1.1}NiO{sub 4}/LaAlO{sub 3} (LSNO/LAO) stack. (1 0 0) oriented CCTO films have been formed through both deposition routes and film complete structural and morphological characterizations have been carried out using several techniques (X-ray diffraction, scanning electron microscopy, energy-filtered transmission electron microscopy). The comparative study demonstrated some differences at the CCTO/LSNO interfaces depending on the adopted deposition technique. Chemical/structural modification of the LSNO electrode probably occurred as a function of the different oxygen partial pressure used in the PLD and MOCVD processes.

  14. Altered network timing in the CA3-CA1 circuit of hippocampal slices from aged mice.

    Directory of Open Access Journals (Sweden)

    Daniel J Kanak

    Full Text Available Network patterns are believed to provide unique temporal contexts for coordinating neuronal activity within and across different regions of the brain. Some of the characteristics of network patterns modeled in vitro are altered in the CA3 or CA1 subregions of hippocampal slices from aged mice. CA3-CA1 network interactions have not been examined previously. We used slices from aged and adult mice to model spontaneous sharp wave ripples and carbachol-induced gamma oscillations, and compared measures of CA3-CA1 network timing between age groups. Coherent sharp wave ripples and gamma oscillations were evident in the CA3-CA1 circuit in both age groups, but the relative timing of activity in CA1 stratum pyramidale was delayed in the aged. In another sample of aged slices, evoked Schaffer collateral responses were attenuated in CA3 (antidromic spike amplitude and CA1 (orthodromic field EPSP slope. However, the amplitude and timing of spontaneous sharp waves recorded in CA1 stratum radiatum were similar to adults. In both age groups unit activity recorded juxtacellularly from unidentified neurons in CA1 stratum pyramidale and stratum oriens was temporally modulated by CA3 ripples. However, aged neurons exhibited reduced spike probability during the early cycles of the CA3 ripple oscillation. These findings suggest that aging disrupts the coordination of patterned activity in the CA3-CA1 circuit.

  15. A Comparative Study of Structural Stability and Mechanical and Optical Properties of Fluorapatite (Ca5(PO4)3F) and Lithium Disilicate (Li2Si2O5) Components Forming Dental Glass-Ceramics: First Principles Study

    Science.gov (United States)

    Biskri, Z. E.; Rached, H.; Bouchear, M.; Rached, D.; Aida, M. S.

    2016-10-01

    The aim of this paper is a comparative study of structural stability and mechanical and optical properties of fluorapatite (FA) (Ca5(PO4)3F) and lithium disilicate (LD) (Li2Si2O5), using the first principles pseudopotential method based on density functional theory (DFT) within the generalized gradient approximation (GGA). The stability of fluorapatite and lithium disilicate compounds has been evaluated on the basis of their formation enthalpies. The results show that fluorapatite is more energetically stable than lithium disilicate. The independent elastic constants and related mechanical properties, including bulk modulus ( B), shear modulus ( G), Young's modulus ( E) and Poisson's ratio ( ν) as well as the Vickers hardness ( H v), have been calculated for fluorapatite compound and compared with other theoretical and experimental results. The obtained values of the shear modulus, Young's modulus and Vickers hardness are smaller in comparison with those of lithium disilicate compound, implying that lithium disilicate is more rigid than fluorapatite. The brittle and ductile properties were also discussed using B/ G ratio and Poisson's ratio. Optical properties such as refractive index n( ω), extinction coefficient k( ω), absorption coefficient α( ω) and optical reflectivity R( ω) have been determined from the calculations of the complex dielectric function ɛ( ω), and interpreted on the basis of the electronic structures of both compounds. The calculated values of static dielectric constant ɛ 1(0) and static refractive index n(0) show that the Li2Si2O5 compound has larger values compared to those of the Ca5(PO4)3F compound. The results of the extinction coefficient show that Li2Si2O5 compound exhibits a much stronger ultraviolet absorption. According to the absorption and reflectivity spectra, we inferred that both compounds are theoretically the best visible and infrared transparent materials.

  16. The prognostic value of preoperative serum levels of CEA, CAl9-9 and CA72-4 in patients with colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Chao Xu Zheng; Wen Hua Zhan; Ji Zong Zhao; Dong Zheng; Dong Ping Wang; Yu Long He; Zhang Qing Zheng

    2001-01-01

    @@INTRODUCTION Carcinoembryonic antigen ( CEA) , originally described by Gold and Freedman [1] in 1965, is now an acknowledged member of immunoglobulin superfamily[2],with a role as an intracellular adhesion molecule[3].Carbohydrate antigen 19-9(CA19-9), obtained with a monoclonal antibody produced by immunizing a monoclonal antibody produced by immunizing a mouse with a colonic cancer cell line in 1979[4],is a ligand for E-selectin that plays an important role in the addhesion of cancer cells to endothelial cells [5,6].

  17. Comparative dielectric studies of nanostructured BaTiO{sub 3}, CaCu{sub 3}Ti{sub 4}O{sub 12} and 0.5BaTiO{sub 3}⋅ 0.5CaCu{sub 3}Ti{sub 4}O{sub 12} nano-composites synthesized by modified sol–gel and solid state methods

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Laxman [Department of Chemistry, University of Ulsan, 93 Daehak-ro Nam-gu, Ulsan 680-749 (Korea, Republic of); Rai, Uma Shanker [Department of Chemistry, Centre of Advanced Study, Faculty of Science, Banaras Hindu University, Varanasi 221005, U.P. (India); Mandal, Kam Deo [Department of Chemistry, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005, U.P. (India); Sin, Byung Cheol; Lee, Hyung-il [Department of Chemistry, University of Ulsan, 93 Daehak-ro Nam-gu, Ulsan 680-749 (Korea, Republic of); Chung, Hoeil [Department of Chemistry, Hanyang University, Haengdang-dong 17, Seongdong-Gu, Seoul 133-791 (Korea, Republic of); Lee, Youngil, E-mail: nmryil@ulsan.ac.kr [Department of Chemistry, University of Ulsan, 93 Daehak-ro Nam-gu, Ulsan 680-749 (Korea, Republic of)

    2014-10-15

    BaTiO{sub 3} (BTO), CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO) and 0.5BaTiO{sub 3}·0.5CaCu{sub 3}Ti{sub 4}O{sub 12} (BTO–CCTO), as a new nano-composite ceramic, were successfully designed and fabricated by a semi-wet gel route and a modified solid state method. The dielectric properties of the BTO–CCTO ceramic were compared to those of the BTO and CCTO ceramics at lower sintering temperatures and durations. The X-ray diffraction analysis revealed that the BTO and CCTO ceramics form a single crystalline phase and the average crystalline sizes calculated from X-ray diffraction data were in the range of 40–65 nm. The particle sizes of the BTO, CCTO, and BTO–CCTO ceramics obtained from transmission electron microscopy images were in the ranges of 40–65 nm, 80–110 nm, and 70–95 nm, respectively. The phase composition and microstructure were studied by X-ray diffraction and scanning electron microscopy. The energy dispersive X-ray results demonstrated the purity and stoichiometry of the BTO–CCTO nano-composite. The grain sizes of the BTO, CCTO and BTO–CCTO ceramics were found to be in the ranges of 500 nm–1 μm, 4–24 μm, and 250 nm–4 μm, respectively. The AC conductivity as a function of frequency confirmed the semiconducting nature of all of the ceramics and obeyed the Jonscher's power law. The impedance spectrum measurement result showed that the CCTO ceramic possessed an exceptional grain boundary resistance, which supports the internal barrier layer capacitance (IBLC) mechanism present in this ceramic and is responsible for the high ε{sub r} values. - Highlights: • Nanostructured BaTiO{sub 3}, CaCu{sub 3}Ti{sub 4}O{sub 12}, and 0.5BaTiO{sub 3}⋅ 0.5CaCu{sub 3}Ti{sub 4}O{sub 12} have been synthesized. • XRD and TEM analysis confirmed the formation of nanoparticles, 40–65 and 50–90 nm. • Impedance analysis shows high grain-boundary resistance present in CCTO ceramic. • AC conductivity as a function of frequency confirms the

  18. Preoperative CA125 and fibrinogen in patients with endometrial cancer: a risk model for predicting lymphovascular space invasion

    Science.gov (United States)

    2017-01-01

    Objective The aim of this study was to build a model to predict the risk of lymphovascular space invasion (LVSI) in women with endometrial cancer (EC). Methods From December 2010 to June 2013, 211 patients with EC undergoing surgery at Shanghai First Maternity and Infant Hospital were enrolled in this retrospective study. Those patients were divided into a positive LVSI group and a negative LVSI group. The clinical and pathological characteristics were compared between the two groups; logistic regression was used to explore risk factors associated with LVSI occurrence. The threshold values of significant factors were calculated to build a risk model and predict LVSI. Results There were 190 patients who were negative for LVSI and 21 patients were positive for LVSI out of 211 patients with EC. It was found that tumor grade, depth of myometrial invasion, number of pelvic lymph nodes, and International Federation of Gynecology and Obstetrics (FIGO) stage (p0.05) were not associated with LVSI. Receiver operating characteristic (ROC) curves revealed that the threshold values of the following factors were correlated with positive LVSI: 28.1 U/mL of CA19-9, 21.2 U/mL of CA125, 2.58 mg/dL of fibrinogen (Fn), 1.84 U/mL of carcinoembryonic antigen (CEA) and (6.35×109)/L of white blood cell (WBC). Logistic regression analysis indicated that CA125 ≥21.2 (p=0.032) and Fn ≥2.58 mg/dL (p=0.014) were significantly associated with LVSI. Conclusion Positive LVSI could be predicted by CA125 ≥21.2 U/mL and Fn ≥2.58 mg/dL in women with EC. It could help gynecologists better adapt surgical staging and adjuvant therapies. PMID:27894164

  19. A comparative study on the electrical parameters of Au/n-Si Schottky diodes with and without interfacial (Ca1.9Pr0.1Co4Ox) layer

    Science.gov (United States)

    Kaya, A.; Çetinkaya, H. G.; Altındal, Ş.; Uslu, I.

    2016-05-01

    In order to compare the main electrical parameters such as ideality factor (n), barrier height (BH) (ΦI-V), series (Rs) and shunt (Rsh) resistances and energy density distribution profile of surface states (Nss), the Au/n-Si (MS) Schotthy diodes (SDs), with and without interfacial (Ca1.9Pr0.1Co4Ox) layer were obtained from the current-voltage (I-V ) measurements at room temperature. The other few electrical parameters such as Fermi energy level (EF), BH (ΦC-V), Rs and voltage dependence of Nss profile were also obtained from the capacitance-voltage (C-V ) measurements. The voltage dependence of Nss profile has two distinctive peaks in the depletion region for two diodes and they were attributed to a particular distribution of Nss located at metal-semiconductor (MS) interface. All of these results have been investigated at room temperature and results have been compared with each other. Experimental results confirmed that interfacial (Ca1.9Pr0.1Co4Ox) layer enhanced diode performance in terms of rectifier rate (RR = IF/IR at ± 3.4V), Nss (at 0.5eV) and Rsh (-3.4V) with values of 265, 5.38 × 1013eV-1 ṡcm-2 and 7.87 × 104Ω for MS type Schottky barrier diode and 2.56 × 106, 1.15 × 1013eV-1 ṡcm-2 and 7.50 × 108Ω for metal-insulator-semiconductor (MIS) type SBD, respectively. It is clear that the rectifying ratio of MIS type SBD is about 9660 times greater than MS type SBD. The value of barrier height (BH) obtained from C-V data is higher than the forward bias I-V data and it was attributed to the nature of measurements. These results confirmed that the interfacial (Ca1.9Pr0.1Co4Ox) layer has considerably improved the performance of SD.

  20. Analysis in patients of the Hospital A.C. Camargo of two tumors markers: CA-72.4 and CYFRA-21.1; Analise em pacientes do Hospital A.C. Camargo de dois marcadores tumorais: CA-72.4 e CYFRA-21.1

    Energy Technology Data Exchange (ETDEWEB)

    Barbuto, Jose Alexandre Marzagao; Oda, Emilia Emiko; Oliveira, Ricardo Manoel de [Fundacao Antonio Prudente, Sao Paulo, SP (Brazil). Hospital A.C. Camargo

    1995-03-01

    The behavior of two tumor markers, CA-72.4 and CYFRA-19.9 was analysed in patients of the Hospital A.C. Camargo. The measurement of CA-272.4 serum levels was performed by an automated chemo luminescence assay in 49 patients and proved useful in the two groups analyzed, patients with esophageal tumors and with gastric tumors. In both cases, there was an increase in sensitivity when measurements of this marker was added to that of carcinoembryonic antigen (CEA) and of CA-19.9. The most sensitive associations were of CA-72.4 and CA-19.9 for esophageal tumors and of CA-72.4 and CEA for the gastric tumors. The maker CYFRA-21.1 was analyzed by a radioimmunoassay in 102 normal blood donors and in 20 patients with lung cancer. Among these, CYFRA-21.1 was altered in 55% of the cases. Therefore, CYFRA-21.1 could be considered, as the neuron-specific enolase (NSE), very useful tool for the follow-up lung cancer patients. (author) 6 refs., 3 figs., 3 tabs.

  1. Autonomous CaMKII requires further stimulation by Ca2+/calmodulin for enhancing synaptic strength.

    Science.gov (United States)

    Barcomb, Kelsey; Buard, Isabelle; Coultrap, Steven J; Kulbe, Jacqueline R; O'Leary, Heather; Benke, Timothy A; Bayer, K Ulrich

    2014-08-01

    A hallmark feature of Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII) is generation of autonomous (Ca(2+)-independent) activity by T286 autophosphorylation. Biochemical studies have shown that "autonomous" CaMKII is ∼5-fold further stimulated by Ca(2+)/CaM, but demonstration of a physiological function for such regulation within cells has remained elusive. In this study, CaMKII-induced enhancement of synaptic strength in rat hippocampal neurons required both autonomous activity and further stimulation. Synaptic strength was decreased by CaMKIIα knockdown and rescued by reexpression, but not by mutants impaired for autonomy (T286A) or binding to NMDA-type glutamate receptor subunit 2B (GluN2B; formerly NR2B; I205K). Full rescue was seen with constitutively autonomous mutants (T286D), but only if they could be further stimulated (additional T305/306A mutation), and not with two other mutations that additionally impair Ca(2+)/CaM binding. Compared to rescue with wild-type CaMKII, the CaM-binding-impaired mutants even had reduced synaptic strength. One of these mutants (T305/306D) mimicked an inhibitory autophosphorylation of CaMKII, whereas the other one (Δstim) abolished CaM binding without introducing charged residues. Inhibitory T305/306 autophosphorylation also reduced GluN2B binding, but this effect was independent of reduced Ca(2+)/CaM binding and was not mimicked by T305/306D mutation. Thus, even autonomous CaMKII activity must be further stimulated by Ca(2+)/CaM for enhancement of synaptic strength.

  2. When is high-Ca+ microdomain required for mitochondrial Ca+ uptake?

    Science.gov (United States)

    Spät, A; Fülöp, L; Koncz, P; Szanda, G

    2009-01-01

    Ca(2+) release from IP(3)-sensitive stores in the endoplasmic reticulum (ER) induced by Ca(2+)-mobilizing agonists generates high-Ca(2+) microdomains between ER vesicles and neighbouring mitochondria. Here we present a model that describes when such microdomains are required and when submicromolar [Ca(2+)] is sufficient for mitochondrial Ca(2+) uptake. Mitochondrial Ca(2+) uptake rate in angiotensin II-stimulated H295R adrenocortical cells correlates with the proximity between ER vesicles and the mitochondrion, reflecting the uptake promoting effect of high-Ca(2+) peri-mitochondrial microdomains. Silencing or inhibition of p38 mitogen-activated protein kinase (MAPK) or inhibition of the novel isoforms of protein kinase C enhances mitochondrial Ca(2+) uptake and abolishes the positive correlation between Ca(2+) uptake and ER-mitochondrion proximity. Inhibition of protein phosphatases attenuates mitochondrial Ca(2+) uptake and also abolishes its positive correlation with ER-mitochondrion proximity. We postulate that during IP(3)-induced Ca(2+) release, Ca(2+) uptake is confined to ER-close mitochondria, because of the simultaneous activation of the protein kinases. Attenuation of Ca(2+) uptake prevents Ca(2+) overload of mitochondria and thus protects the cell against apoptosis. On the other hand, all the mitochondria accumulate Ca(2+) at a non-inhibited rate during physiological Ca(2+) influx through the plasma membrane. Membrane potential is higher in ER-distant mitochondria, providing a bigger driving force for Ca(2+) uptake. Our model explains why comparable mitochondrial Ca(2+) signals are formed in response to K(+) and angiotensin II (equipotent in respect to global cytosolic Ca(2+) signals), although only the latter generates high-Ca(2+) microdomains.

  3. Comparative study of perovskite Pr{sub (1-x)}Ca{sub x}CoO{sub 3} e Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x=0,2) synthesized by gelatin modified route for application in automotive catalysis; Estudo comparativo das perovsquitas Pr{sub (1-x)}Ca{sub x}CoO{sub 3} e Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x=0,2) sintetizadas pela rota modificada gelatina para aplicacao em catalise automotiva

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, E.M. de; Medeiros, M.R.A.; Paiva, A.K.O.; Borges, F.M.M., E-mail: eduardamedeirosdearaujo@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil); Ruiz, J.A.C. [Centro de Tecnologia do Gas e Energias Renovaveis (CTGAS-ER), RN (Brazil)

    2016-07-01

    Increased air pollution intensified the search for materials that could convert pollutant gases into less harmful substances. Thus, mixed oxides with perovskite structure began to be developed for presenting important features for the automotive catalysis. In this study has been compared the chemical composition of the materials with Pr{sub (1-x)}Ca{sub x}CoO{sub 3} and Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x = 0.2) synthesized by the method gelatine. The samples were characterized by techniques: Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-Ray Diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray fluorescence (XRF) and subjected to the catalytic test in methane combustion reaction. The evaluation of the catalytic activity showed that gadolinium catalyst is more efficient compared with the praseodymium catalyst, although they have similar maximum conversion of methane at high temperature, during the catalytic test the material with gadolinium showed higher catalytic activity and stability. (author)

  4. Ca2+ cycling in heart cells from ground squirrels: adaptive strategies for intracellular Ca2+ homeostasis.

    Directory of Open Access Journals (Sweden)

    Xiao-Chen Li

    Full Text Available Heart tissues from hibernating mammals, such as ground squirrels, are able to endure hypothermia, hypoxia and other extreme insulting factors that are fatal for human and nonhibernating mammals. This study was designed to understand adaptive mechanisms involved in intracellular Ca(2+ homeostasis in cardiomyocytes from the mammalian hibernator, ground squirrel, compared to rat. Electrophysiological and confocal imaging experiments showed that the voltage-dependence of L-type Ca(2+ current (I(Ca was shifted to higher potentials in ventricular myocytes from ground squirrels vs. rats. The elevated threshold of I(Ca did not compromise the Ca(2+-induced Ca(2+ release, because a higher depolarization rate and a longer duration of action potential compensated the voltage shift of I(Ca. Both the caffeine-sensitive and caffeine-resistant components of cytosolic Ca(2+ removal were more rapid in ground squirrels. Ca(2+ sparks in ground squirrels exhibited larger amplitude/size and much lower frequency than in rats. Due to the high I(Ca threshold, low SR Ca(2+ leak and rapid cytosolic Ca(2+ clearance, heart cells from ground squirrels exhibited better capability in maintaining intracellular Ca(2+ homeostasis than those from rats and other nonhibernating mammals. These findings not only reveal adaptive mechanisms of hibernation, but also provide novel strategies against Ca(2+ overload-related heart diseases.

  5. Comparative Study of Gemcitabine Plus Cisplatin and Gemcitabine Plus Fluorouracil in the Treatment of Advanced Pancreatic Cancer

    Institute of Scientific and Technical Information of China (English)

    YongqionShu; LiankeLiu; LinxiangLiu; PuwenHuang; KoihuoLu; YongmeiYin

    2004-01-01

    OBJECTIVE To compare the efficacy and toxicity of gemcitabine plus cisplatin and gemcitabine plus fluorouracil in the treatment of advanced pancreatic cancer. METHODS Sixty patients with advanced pancreatic cancer were randomly divided into a GP group (gemcitabine + cisplatin, 30 cases) and a GF group (gemcitabine + fluorouracil, 30 cases). All patients were treated with gemcitabine at a dose of 1,000mg/m2 (diluted in 100ml saline solution over 30 min) once a week for 3 consecutive weeks. The GP Group was followed by 40mg cisplatin via intravenous drip on days 15,16,17. Group GF was followed by 500mg/m2 5-Fu (diluted in 5% glucose-saline (GS) 500ml, intravenously, over 6 hr) every day for five subsequent days.RESULTS In the GP group, eight cases (32.0%) were PR and MR, the median survival time was 8.7 months, the Clinical Beneficial Rate (CBR) was 57.7%, and the CA19-9 decreased by over 50% in 13 vases (48.1%). In the GF group, 11 cases (45.8%) were PR and MR, the survival time was 10.1 months, the CBR was 82.1%, and CA19-9 decreased by over 50% in 15 cases(53.6%). There was a significant difference in the CBR between the two groups (P<0.05). The main toxicities in both groups were leucopenia and thrombocytopenia with no significant difference. CONCLUSIONS The treatment given to either the GP or GF group is a feasible and well-tolerated chemotherapy regimen for treating advanced pancreatic cancer with improved therapeutic efficacy and few side effects. The median survival period is long and the CBR is high, especially with the GF regimen.

  6. Neural Signals Related to Outcome Evaluation Are Stronger in CA1 than CA3.

    Science.gov (United States)

    Lee, Sung-Hyun; Huh, Namjung; Lee, Jong Won; Ghim, Jeong-Wook; Lee, Inah; Jung, Min W

    2017-01-01

    We have shown previously that CA1 conveys significant neural signals necessary to update value of the chosen target, namely chosen value and reward signals. To better understand hippocampal neural processes related to valuation, we compared chosen value- and reward-related neural activity between the CA3 and CA1 regions. Single units were recorded with tetrodes from the dorsal CA3 and CA1 regions of rats performing a dynamic foraging task, and chosen value- and reward-related neural activity was estimated using a reinforcement learning model and multiple regression analyses. Neural signals for chosen value and reward converged in both CA3 and CA1 when a trial outcome was revealed. However, these neural signals were stronger in CA1 than CA3. Consequently, neural signals for reward prediction error and updated chosen value were stronger in CA1 than CA3. Together with our previous finding that CA1 conveys stronger value signals than the subiculum, our results raise the possibility that CA1 might play a particularly important role among hippocampal subregions in evaluating experienced events.

  7. Comparative study on the adsorption of Co{sup 2+} on CaCO{sub 3} compounds used as adsorbents; Estudio comparativo sobre la adsorcion de Co{sup 2+} sobre compuestos de CaCO{sub 3} utilizados como adsorbentes

    Energy Technology Data Exchange (ETDEWEB)

    De Jesus V, S.

    2014-07-01

    The calcium carbonate (CaCO{sub 3}) was synthesized by methods of precipitation, calcination, sol-gel and trigonal/sol-gel. These materials were characterized by the techniques of X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, infrared spectroscopy and N{sub 2} physisorption measurements in order to identify their textural, surface and structural properties. The results show that the material synthesized by sol-gel had the highest surface area of 39.5230 m{sup 2}/g, and a total pore volume of 0.0484 m{sup 3}/g and a pore diameter of 4.9050 nm. The synthesized materials were used to comparatively study their adsorption capacity of Co{sup 2+} ions present in aqueous solutions, by experiments batch or batch type at an ambient temperature (25 grades C) and to 4 hours, balance time established previously under an adsorption kinetic study. They found as maximum adsorption capacities of Co{sup 2+} in materials of 1.8582 mg/g for the calcium carbonate obtained by precipitation, of 0.8586 mg/g for the material obtained by calcining, of 3.1895 mg/g for the material obtained by sol-gel and finally of 2.5783 mg/g for the material obtained by the trigonal/sol-gel method, therefore it follows that the material having the highest adsorption capacity of Co{sup 2+} ions was synthesized by the sol-gel method, because it showed better surface, textural and structural properties compared to other materials studied. (Author)

  8. Genetically encoded green fluorescent Ca2+ indicators with improved detectability for neuronal Ca2+ signals.

    Science.gov (United States)

    Ohkura, Masamichi; Sasaki, Takuya; Sadakari, Junko; Gengyo-Ando, Keiko; Kagawa-Nagamura, Yuko; Kobayashi, Chiaki; Ikegaya, Yuji; Nakai, Junichi

    2012-01-01

    Imaging the activities of individual neurons with genetically encoded Ca(2+) indicators (GECIs) is a promising method for understanding neuronal network functions. Here, we report GECIs with improved neuronal Ca(2+) signal detectability, termed G-CaMP6 and G-CaMP8. Compared to a series of existing G-CaMPs, G-CaMP6 showed fairly high sensitivity and rapid kinetics, both of which are suitable properties for detecting subtle and fast neuronal activities. G-CaMP8 showed a greater signal (F(max)/F(min) = 38) than G-CaMP6 and demonstrated kinetics similar to those of G-CaMP6. Both GECIs could detect individual spikes from pyramidal neurons of cultured hippocampal slices or acute cortical slices with 100% detection rates, demonstrating their superior performance to existing GECIs. Because G-CaMP6 showed a higher sensitivity and brighter baseline fluorescence than G-CaMP8 in a cellular environment, we applied G-CaMP6 for Ca(2+) imaging of dendritic spines, the putative postsynaptic sites. By expressing a G-CaMP6-actin fusion protein for the spines in hippocampal CA3 pyramidal neurons and electrically stimulating the granule cells of the dentate gyrus, which innervate CA3 pyramidal neurons, we found that sub-threshold stimulation triggered small Ca(2+) responses in a limited number of spines with a low response rate in active spines, whereas supra-threshold stimulation triggered large fluorescence responses in virtually all of the spines with a 100% activity rate.

  9. Irinotecan plus gemcitabine results in no survival advantage compared with gemcitabine monotherapy in patients with locally advanced or metastatic pancreatic cancer despite increased tumor response rate.

    Science.gov (United States)

    Rocha Lima, Caio M; Green, Mark R; Rotche, Robert; Miller, Wilson H; Jeffrey, G Mark; Cisar, Laura A; Morganti, Adele; Orlando, Nicoletta; Gruia, Gabriela; Miller, Langdon L

    2004-09-15

    This phase III, randomized, open-label, multicenter study compared the overall survival associated with irinotecan plus gemcitabine (IRINOGEM) versus gemcitabine monotherapy (GEM) in patients with chemotherapy-naive, locally advanced or metastatic pancreatic cancer. IRINOGEM patients received starting doses of gemcitabine 1,000 mg/m2 and irinotecan 100 mg/m2 given weekly for 2 weeks every 3-week cycle. GEM patients received gemcitabine 1,000 mg/m2 weekly for 7 of 8 weeks (induction) and then weekly for 3 of 4 weeks. The primary end point of the trial was survival. Secondary end points included tumor response, time to tumor progression (TTP), changes in CA 19-9, and safety. In each arm, 180 randomly assigned patients comprised the intent-to-treat population evaluated for efficacy; 173 IRINOGEM and 169 GEM patients were treated. Median survival times were 6.3 months for IRINOGEM (95% CI, 4.7 to 7.5 months) and 6.6 months for GEM (95% CI, 5.2 to 7.8 months; log-rank P =.789). Tumor response rates were 16.1% (95% CI, 11.1% to 22.3%) for IRINOGEM and 4.4% (95% CI, 1.9% to 8.6%) for GEM (chi2 P <.001). Median TTP was 3.5 months for IRINOGEM versus 3.0 months for GEM (log-rank P =.352). However, subset analyses in patients with locally advanced disease suggested a TTP advantage with IRINOGEM versus GEM (median, 7.7 v 3.9 months). CA 19-9 progression was positively correlated with tumor progression. The incidence of grade 3 diarrhea was higher in the IRINOGEM group but grade 3 to 4 hematologic toxicities and quality-of-life outcomes were similar. IRINOGEM safely improved the tumor response rate compared with GEM but did not alter overall survival.

  10. Biphasic decay of the Ca transient results from increased sarcoplasmic reticulum Ca leak

    Science.gov (United States)

    Sankaranarayanan, Rajiv; Li, Yatong; Greensmith, David J.; Eisner, David A.

    2016-01-01

    Key points Ca leak from the sarcoplasmic reticulum through the ryanodine receptor (RyR) reduces the amplitude of the Ca transient and slows its rate of decay.In the presence of β‐adrenergic stimulation, RyR‐mediated Ca leak produces a biphasic decay of the Ca transient with a fast early phase and a slow late phase.Two forms of Ca leak have been studied, Ca‐sensitising (induced by caffeine) and non‐sensitising (induced by ryanodine) and both induce biphasic decay of the Ca transient.Only Ca‐sensitising leak can be reversed by traditional RyR inhibitors such as tetracaine.Ca leak can also induce Ca waves. At low levels of leak, waves occur. As leak is increased, first biphasic decay and then slowed monophasic decay is seen. The level of leak has major effects on the shape of the Ca transient. Abstract In heart failure, a reduction in Ca transient amplitude and contractile dysfunction can by caused by Ca leak through the sarcoplasmic reticulum (SR) Ca channel (ryanodine receptor, RyR) and/or decreased activity of the SR Ca ATPase (SERCA). We have characterised the effects of two forms of Ca leak (Ca‐sensitising and non‐sensitising) on calcium cycling and compared with those of SERCA inhibition. We measured [Ca2+]i with fluo‐3 in voltage‐clamped rat ventricular myocytes. Increasing SR leak with either caffeine (to sensitise the RyR to Ca activation) or ryanodine (non‐sensitising) had similar effects to SERCA inhibition: decreased systolic [Ca2+]i, increased diastolic [Ca2+]i and slowed decay. However, in the presence of isoproterenol, leak produced a biphasic decay of the Ca transient in the majority of cells while SERCA inhibition produced monophasic decay. Tetracaine reversed the effects of caffeine but not of ryanodine. When caffeine (1 mmol l−1) was added to a cell which displayed Ca waves, the wave frequency initially increased before waves disappeared and biphasic decay developed. Eventually (at higher caffeine concentrations), the

  11. Fusion calculations for 40Ca+40Ca, 48Ca+48Ca, 40Ca+48Ca and p+208Pb systems

    Science.gov (United States)

    Gao, Jie; Zhang, Haifei; Bao, Xiaojun; Li, Junqing; Zhang, Hongfei

    2014-09-01

    The fusion cross sections of calcium isotopes and proton induced fusion have been calculated in terms of a coupled-channels formulation. Results indicated that there are big differences between the two fusion types. In the calculations of calcium isotopes fusion, the pair-transfer coupling has been applied in addition to the vibrational coupling, the combined effects showed that pair-transfer has played a significant role in the fusion process for the asymmetric 40Ca+48Ca system. The result of proton induced fusion for p+208Pb system successfully presents the fusion oscillation, which agrees with the experimental data rather well.

  12. Ruptura y continuidad: la caída de «Mel» Zelaya en perspectiva comparada Continuity and rupture: the fall of ‹‹Mel›› Zelaya in a comparative perspective

    Directory of Open Access Journals (Sweden)

    Leiv MARSTEINTREDET

    2010-09-01

    Full Text Available

    Este artículo analiza y compara la deposición del presidente de Honduras, Manuel Zelaya, con otras crisis presidenciales acontecidas en América Latina durante la tercera ola de democratización. El trabajo indaga sobre los procedimientos, causas y consecuencias en torno de esta caída presidencial con instrumentos de análisis previstos por la teoría de las rupturas presidenciales. La caída de Zelaya fue producto de una escalada de conflictos interinstitucionales, protagonizados por las elites civiles del país. En perspectiva comparada, el caso se distingue por la intervención de los militares como poder moderador a invitación de las instituciones civiles, la falta de movilización popular antes del golpe y la irrupción de una crisis internacional y conflictos callejeros después de que la caída presidencial tuviera lugar. El caso de Honduras contribuye a la teoría de las rupturas presidenciales al poner el acento en el papel de los militares y el estadio de desarrollo en que se encuentra el régimen político democrático al estallar la crisis.

    Control of ciliary motility by Ca sup 2+ : Integration of Ca sup 2+ -dependent functions and targets for Ca sup 2+ action

    Energy Technology Data Exchange (ETDEWEB)

    Evans, T.C.

    1988-01-01

    To identify functions that regulate Ca{sup 2+}-induced ciliary reversal in Paramecium, mutants defective in terminating depolarization-induced backward swimming were selected. Six independent recessive mutations (k-shy) comprising two complementation groups, k-shyA and k-shyB, were identified. All mutants exhibited prolonged backward swimming in depolarizing solutions. Voltage clamp studies revealed that mutant Ca{sup 2+} current amplitudes were reduced, but could be restored to wild type levels by EGTA injection. The recovery of the mutant Ca{sup 2+} current from Ca{sup 2+}-dependent inactivation, and the decay of the Ca{sup 2+}-dependent K{sup +} and Ca{sup 2+}-dependent Na{sup +} currents after depolarization were slow in k-shy compared to wild type. To identify protein targets of Ca{sup 2+} action, ciliary proteins that interact with calmodulin (CaM) were characterized. With a {sup 125}I-CaM blot assay, several CaM-binding proteins were identified including axonemal, soluble, and membrane-bound polypeptides. Competitive displacement studies with unlabeled Paramecium CaM, bovine CaM, and troponinC suggested that both protein types bind CaM with high affinity and specificity. To examine the presence of CaM-binding sites in intact axonemes, a filtration binding assay was developed.

  13. A significant but rather mild contribution of T286 autophosphorylation to Ca2+/CaM-stimulated CaMKII activity.

    Directory of Open Access Journals (Sweden)

    Steven J Coultrap

    Full Text Available BACKGROUND: Autophosphorylation of the Ca(2+/calmodulin (CaM-dependent protein kinase II (CaMKII at T286 generates partially Ca(2+/CaM-independent "autonomous" activity, which is thought to be required for long-term potentiation (LTP, a form of synaptic plasticity thought to underlie learning and memory. A requirement for T286 autophosphorylation also for efficient Ca(2+/CaM-stimulated CaMKII activity has been described, but remains controversial. METHODOLOGY/PRINCIPAL FINDINGS: In order to determine the contribution of T286 autophosphorylation to Ca(2+/CaM-stimulated CaMKII activity, the activity of CaMKII wild type and its phosphorylation-incompetent T286A mutant was compared. As the absolute activity can vary between individual kinase preparations, the activity was measured in six different extracts for each kinase (expressed in HEK-293 cells. Consistent with measurements on purified kinase (from a baculovirus/Sf9 cell expression system, CaMKII T286A showed a mildly but significantly reduced rate of Ca(2+/CaM-stimulated phosphorylation for two different peptide substrates (to ~75-84% of wild type. Additional slower CaMKII autophosphorylation at T305/306 inhibits stimulation by Ca(2+/CaM, but occurs only minimally for CaMKII wild type during CaM-stimulated activity assays. Thus, we tested if the T286A mutant may show more extensive inhibitory autophosphorylation, which could explain its reduced stimulated activity. By contrast, inhibitory autophosphorylation was instead found to be even further reduced for the T286A mutant under our assay conditions. On a side note, the phospho-T305 antibody showed some basal background immuno-reactivity also with non-phosphorylated CaMKII, as indicated by T305/306A mutants. CONCLUSIONS/SIGNIFICANCE: These results indicate that Ca(2+/CaM-stimulated CaMKII activity is mildly (~1.2-1.3fold further increased by additional T286 autophosphorylation, but that this autophosphorylation is not required for the major

  14. The Ca(2+)/Calmodulin/CaMKK2 Axis: Nature's Metabolic CaMshaft.

    Science.gov (United States)

    Marcelo, Kathrina L; Means, Anthony R; York, Brian

    2016-10-01

    Calcium (Ca(2+)) is an essential ligand that binds its primary intracellular receptor calmodulin (CaM) to trigger a variety of downstream processes and pathways. Central to the actions of Ca(2+)/CaM is the activation of a highly conserved Ca(2+)/CaM kinase (CaMK) cascade that amplifies Ca(2+) signals through a series of subsequent phosphorylation events. Proper regulation of Ca(2+) flux is necessary for whole-body metabolism and disruption of Ca(2+) homeostasis has been linked to various metabolic diseases. Here we provide a synthesis of recent advances that highlight the roles of the Ca(2+)/CaMK axis in key metabolic tissues. An appreciation of this information is critical to understanding the mechanisms by which Ca(2+)/CaM-dependent signaling contributes to metabolic homeostasis and disease.

  15. Reduction of Ca2+-transporting systems in memory T cells.

    Science.gov (United States)

    Sigova, A A; Dedkova, E N; Zinchenko, V P; Litvinov, I S

    2000-01-01

    Antigen-specific B and T lymphocytes make up the material grounds of immune memory, their main functional distinction from the so-called "naive" cells is due to the rapid and enhanced response to the antigen-pathogen. An essential distinction between the memory and naive T cells is different sensitivity of these two subpopulations of T lymphocytes to Ca2+-ionophores. Comparative analysis of Ca2+ responses of the immune memory T lymphocytes and naive T cells of mouse CBA/J line to the addition of Ca2+-mobilizing agents concanavalin A, thapsigargin, and ionomycin was carried out. These compounds in concentrations increasing [Ca2+]i in naive cells had no effect on [Ca2+]i in memory cells. Thus, the Ca2+ entrance into memory cells was not activated by exhaustion of intracellular resources. Estimation of intracellular resources of Ca2+, mobilized by ionomycin and thapsigargin in Ca2+ free medium has shown the absence in memory T cells of the intracellular Ca2+ pool, which may be one of factors of their resistance to ionophores. Reduction of the system of Ca2+ influx into memory T cells was shown using the SH-reagent thimerosal. Memory T cells appear to be resistant to "Ca2+ -paradox." Their incubation with 0.5 mM EDTA in the presence or absence of Ca2+ -mobilizing compounds followed by addition of 2 mM CaCl2 did not result in induction of Ca2+ influx into these cells.

  16. Honeybee locomotion is impaired by Am-CaV3 low voltage-activated Ca(2+) channel antagonist.

    Science.gov (United States)

    Rousset, M; Collet, C; Cens, T; Bastin, F; Raymond, V; Massou, I; Menard, C; Thibaud, J-B; Charreton, M; Vignes, M; Chahine, M; Sandoz, J C; Charnet, P

    2017-02-01

    Voltage-gated Ca(2+) channels are key transducers of cellular excitability and participate in several crucial physiological responses. In vertebrates, 10 Ca(2+) channel genes, grouped in 3 families (CaV1, CaV2 and CaV3), have been described and characterized. Insects possess only one member of each family. These genes have been isolated in a limited number of species and very few have been characterized although, in addition to their crucial role, they may represent a collateral target for neurotoxic insecticides. We have isolated the 3 genes coding for the 3 Ca(2+) channels expressed in Apis mellifera. This work provides the first detailed characterization of the honeybee T-type CaV3 Ca(2+) channel and demonstrates the low toxicity of inhibiting this channel. Comparing Ca(2+) currents recorded in bee neurons and myocytes with Ca(2+) currents recorded in Xenopus oocytes expressing the honeybee CaV3 gene suggests native expression in bee muscle cells only. High-voltage activated Ca(2+) channels could be recorded in the somata of different cultured bee neurons. These functional data were confirmed by in situ hybridization, immunolocalization and in vivo analysis of the effects of a CaV3 inhibitor. The biophysical and pharmacological characterization and the tissue distribution of CaV3 suggest a role in honeybee muscle function.

  17. Honeybee locomotion is impaired by Am-CaV3 low voltage-activated Ca2+ channel antagonist

    Science.gov (United States)

    Rousset, M.; Collet, C.; Cens, T.; Bastin, F.; Raymond, V.; Massou, I.; Menard, C.; Thibaud, J.-B.; Charreton, M.; Vignes, M.; Chahine, M.; Sandoz, J. C.; Charnet, P.

    2017-01-01

    Voltage‐gated Ca2+ channels are key transducers of cellular excitability and participate in several crucial physiological responses. In vertebrates, 10 Ca2+ channel genes, grouped in 3 families (CaV1, CaV2 and CaV3), have been described and characterized. Insects possess only one member of each family. These genes have been isolated in a limited number of species and very few have been characterized although, in addition to their crucial role, they may represent a collateral target for neurotoxic insecticides. We have isolated the 3 genes coding for the 3 Ca2+ channels expressed in Apis mellifera. This work provides the first detailed characterization of the honeybee T-type CaV3 Ca2+ channel and demonstrates the low toxicity of inhibiting this channel. Comparing Ca2+ currents recorded in bee neurons and myocytes with Ca2+ currents recorded in Xenopus oocytes expressing the honeybee CaV3 gene suggests native expression in bee muscle cells only. High‐voltage activated Ca2+ channels could be recorded in the somata of different cultured bee neurons. These functional data were confirmed by in situ hybridization, immunolocalization and in vivo analysis of the effects of a CaV3 inhibitor. The biophysical and pharmacological characterization and the tissue distribution of CaV3 suggest a role in honeybee muscle function. PMID:28145504

  18. Comparative study of perovskites obtained by using polymeric precursors with composition La{sub 0,6}Ca{sub 0,4}(Co, Mn)O{sub 3} for use in combustion catalysis; Estudo comparativo de perovsquitas obtidas pelo metodo dos precursores polimericos com composicao La{sub 0,6}Ca{sub 0,4}(Co, Mn)O{sub 3} para utilizacao em catalise de combustao

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Ana Karenina de Oliveira; Wanderley, Jose Bruno de Moura; Batista, Jonathan Jalles Silva; Borges, Filipe Martel de Magalhaes; Melo, Dulce Maria de Araujo, E-mail: kareninapaiva@hotmail.com [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2012-07-01

    Materials with the perovskite structure are potential catalysts to reduce emissions of pollutants components into the environment. In the synthesis of perovskites, several methods have been proposed. In this work, lanthanum manganate compositions and lanthanum cobaltate with partial substitution of calcium (La{sub 0.6}Ca{sub 0.4}MnO{sub 3} and La{sub 0.6}Ca{sub 0.4}CoO{sub 3}, respectively), were synthesized using the polymeric precursor method. The powders obtained after 4h at 300° C (5° C/min), were calcined at temperatures of 700 and 900° C for 4 h (10° C/min), and characterized by X-ray Diffraction and Scanning Electron Microscopy. Comparing the X-ray Diffraction of the compositions manganate and lanthanum cobaltate, as the temperature increases, there is an increase in crystallinity, even more evident in manganate. TG curves showed similar thermal stabilities, with greater weight loss for the material cobaltate. The perovskites obtained were single phased, nanometric and had good porosity, making these potential catalysts appropriate properties for application in combustion reactions (author)

  19. Differential Ca2+ influx, KCa channel activity, and Ca2+ clearance distinguish Th1 and Th2 lymphocytes.

    Science.gov (United States)

    Fanger, C M; Neben, A L; Cahalan, M D

    2000-02-01

    In Th1 and Th2 lymphocytes, activation begins with identical stimuli but results in the production of different cytokines. The expression of some cytokine genes is differentially induced according to the amplitude and pattern of Ca2+ signaling. Using fura- 2 Ca2+ imaging of murine Th1 and Th2 clones, we observed that the Ca2+ rise elicited following store depletion with thapsigargin is significantly lower in Th2 cells than in Th1 cells. Maximal Ca2+ influx rates and whole-cell Ca2+ currents showed that both Th1 and Th2 cells express indistinguishable Ca2+-release-activated Ca2+ channels. Therefore, we investigated other mechanisms controlling the concentration of intracellular Ca2+, including K+ channels and Ca2+ clearance from the cytosol. Whole-cell recording demonstrated that there is no distinction in the amplitudes of voltage-gated K+ currents in the two cell types. Ca2+-activated K+ (KCa) currents, however, were significantly smaller in Th2 cells than in Th1 cells. Pharmacological equalization of Ca2+-activated K+ currents in the two cell types reduced but did not completely eliminate the difference between Th1 and Th2 Ca2+ responses, suggesting divergence in an additional Ca2+ regulatory mechanism. Therefore, we analyzed Ca2+ clearance from the cytosol of both cell types and found that Th2 cells extrude Ca2+ more quickly than Th1 cells. The combination of a faster Ca2+ clearance mechanism and smaller Ca2+-activated K+ currents in Th2 cells accounts for the lower Ca2+ response of Th2 cells compared with Th1 cells.

  1. 22 CFR 19.9-2 - Commencement and termination.

    Science.gov (United States)

    2010-04-01

    ...) The pension of a former spouse under this subsection commences on the latter of the day the principal becomes entitled to a Foreign Service annuity or on the first day of the month in which the divorce becomes final. (Suspension or reduction of a Foreign Service annuity because or reemployment does...

  2. Characterization of 19.9% Efficient CIGS Absorbers: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Repins, I.; Contreras, M.; Romero, M.; Yan, Y.; Metzger, W.; Li, J.; Johnston, S.; Egass, B.; DeHart, C.; Scharf, J.; McCandless, B. E.; Noufi, R.

    2008-05-01

    This paper documents the properties of the world-record-efficiency CIGS solar cell by a variety of characterization techniques, with an emphasis on identifying near-surface properties associated with the modified processing.

  3. 有关CA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ 什么是CA? CA(Certificaton Authority)是认证机构的国际通称,是指对数字证书的申请者发放、管理、取消数字证书的机构.CA的作用是检查证书持有者身份的合法性,并签发证书(在证书上签字),以防证书被伪造或篡改.

  4. Sr/Ca and Ba/Ca variations in environmental and biological sources: A survey of marine and terrestrial systems

    Science.gov (United States)

    Peek, Stephanie; Clementz, Mark T.

    2012-10-01

    The relative concentrations of strontium to calcium (Sr/Ca) and barium to calcium (Ba/Ca) in mammalian bioapatite are common biogeochemical indicators for trophic level and/or dietary preferences in terrestrial foodwebs; however, similar research in marine foodwebs is lacking. This study combined environmental and biological Sr/Ca and Ba/Ca data from both terrestrial and marine settings from 62 published books, reports, and studies along with original data collected from 149 marine mammals (30 species) and 83 prey items (18 species) and found that variations in Sr/Ca and Ba/Ca ratios of biological and environmental samples are appreciably different in terrestrial and marine systems. In terrestrial systems, environmental sources account for most of the variations in Sr/Ca and Ba/Ca ratios. In contrast, environmental sources in marine systems (i.e., seawater) are comparatively invariant, meaning most of the variations in Sr/Ca and Ba/Ca ratios originate from biological processes. Marine consumers, particularly non-mammalian and mammalian vertebrates, show evidence of biopurification of Ca relative to Sr and Ba, similar to what is observed in terrestrial systems; however, unlike terrestrial systems, variations in Sr/Ca and Ba/Ca ratios of environmental sources are overprinted by bioaccumulation of Sr and Ba at the base of marine foodwebs. This demonstrates that in marine systems, spatial or temporal differences may have little to no effect on Sr/Ca and Ba/Ca ratios of marine vertebrates, making Sr/Ca, and to a lesser extent Ba/Ca, potentially useful global proxies for trophic level and dietary preferences of marine vertebrates.

  5. Topological organization of CA3-to-CA1 excitation.

    Science.gov (United States)

    Hongo, Yoshie; Ogawa, Koichi; Takahara, Yuji; Takasu, Keiko; Royer, Sebastien; Hasegawa, Minoru; Sakaguchi, Gaku; Ikegaya, Yuji

    2015-09-01

    The CA1-projecting axons of CA3 pyramidal cells, called Schaffer collaterals, constitute one of the major information flow routes in the hippocampal formation. Recent anatomical studies have revealed the non-random structural connectivity between CA3 and CA1, but little is known regarding the functional connectivity (i.e. how CA3 network activity is functionally transmitted downstream to the CA1 network). Using functional multi-neuron calcium imaging of rat hippocampal slices, we monitored the spatiotemporal patterns of spontaneous CA3 and CA1 burst activity under pharmacological GABAergic blockade. We found that spatially clustered CA3 activity patterns were transformed into layered CA1 activity sequences. Specifically, synchronized bursts initiated from multiple hot spots in CA3 ensembles, and CA1 neurons located deeper in the pyramidal cell layer were recruited during earlier phases of the burst events. The order of these sequential activations was maintained across the bursts, but the sequence velocity varied depending on the inter-burst intervals. Thus, CA3 axons innervate CA1 neurons in a highly topographical fashion.

  6. Biomarker CA125

    DEFF Research Database (Denmark)

    Kargo, Anette Stolberg

    be detected months before symptoms arise and recurrence is visible on imaging. Therefore, biochemical detection of potential relapse by CA125 assessment can cause significant distress. A decision aid (DA) is a tool that provides information and describes advantages and disadvantages of a specific intervention...

  7. Comparative Cytotoxicity of Glycyrrhiza glabra Roots from Different Geographical Origins Against Immortal Human Keratinocyte (HaCaT), Lung Adenocarcinoma (A549) and Liver Carcinoma (HepG2) Cells.

    Science.gov (United States)

    Basar, Norazah; Oridupa, Olayinka Ayotunde; Ritchie, Kenneth J; Nahar, Lutfun; Osman, Nashwa Mostafa M; Stafford, Angela; Kushiev, Habibjon; Kan, Asuman; Sarker, Satyajit D

    2015-06-01

    Glycyrrhiza glabra L. (Fabaceae), commonly known as 'liquorice', is a well-known medicinal plant. Roots of this plant have long been used as a sweetening and flavouring agent in food and pharmaceutical products, and also as a traditional remedy for cough, upper and lower respiratory ailments, kidney stones, hepatitis C, skin disorder, cardiovascular diseases, diabetes, gastrointestinal ulcers and stomach ache. Previous pharmacological and clinical studies have revealed its antitussive, antiinflammatory, antiviral, antimicrobial, antioxidant, immunomodulatory, hepatoprotective and cardioprotective properties. While glycyrrhizin, a sweet-tasting triterpene saponin, is the principal bioactive compound, several bioactive flavonoids and isoflavonoids are also present in the roots of this plant. In the present study, the cytotoxicity of the methanol extracts of nine samples of the roots of G. glabra, collected from various geographical origins, was assessed against immortal human keratinocyte (HaCaT), lung adenocarcinoma (A549) and liver carcinoma (HepG2) cell lines using the in vitro 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazoliumbromide cell toxicity/viability assay. Considerable variations in levels of cytotoxicity were observed among various samples of G. glabra.

  8. Electrodeposition of Ca Metal in CaCl2-CaO Molten Salt

    Institute of Scientific and Technical Information of China (English)

    GUO; Jun-kang; WANG; Chang-shui; CAO; Long-hao; OUYANG; Ying-gen

    2013-01-01

    To realize the continuouscalciothermic reduction in molten salts,the electrodeposition behavior of Ca metal in CaCl2-CaO molten salt was investigated by cylic voltammetry.The cyclic voltammograms at the scan rate of 100 mV/s are shown in Fig.1.As is shown,the electrodeposition potential of Ca deviated from-1.66 V to-0.97 V after CaO was added to molten CaCl2 and the decomposition of CaO

  9. T-type Ca(2+) channel modulation by otilonium bromide.

    Science.gov (United States)

    Strege, Peter R; Sha, Lei; Beyder, Arthur; Bernard, Cheryl E; Perez-Reyes, Edward; Evangelista, Stefano; Gibbons, Simon J; Szurszewski, Joseph H; Farrugia, Gianrico

    2010-05-01

    Antispasmodics are used clinically to treat a variety of gastrointestinal disorders by inhibition of smooth muscle contraction. The main pathway for smooth muscle Ca(2+) entry is through L-type channels; however, there is increasing evidence that T-type Ca(2+) channels also play a role in regulating contractility. Otilonium bromide, an antispasmodic, has previously been shown to inhibit L-type Ca(2+) channels and colonic contractile activity. The objective of this study was to determine whether otilonium bromide also inhibits T-type Ca(2+) channels. Whole cell currents were recorded by patch-clamp technique from HEK293 cells transfected with cDNAs encoding the T-type Ca(2+) channels, Ca(V)3.1 (alpha1G), Ca(V)3.2 (alpha1H), or Ca(V)3.3 (alpha1I) alpha subunits. Extracellular solution was exchanged with otilonium bromide (10(-8) to 10(-5) M). Otilonium bromide reversibly blocked all T-type Ca(2+) channels with a significantly greater affinity for Ca(V)3.3 than Ca(V)3.1 or Ca(V)3.2. Additionally, the drug slowed inactivation in Ca(V)3.1 and Ca(V)3.3. Inhibition of T-type Ca(2+) channels may contribute to inhibition of contractility by otilonium bromide. This may represent a new mechanism of action for antispasmodics and may contribute to the observed increased clinical effectiveness of antispasmodics compared with selective L-type Ca(2+) channel blockers.

  10. T-type Ca2+ channel modulation by otilonium bromide

    Science.gov (United States)

    Strege, Peter R.; Sha, Lei; Beyder, Arthur; Bernard, Cheryl E.; Perez-Reyes, Edward; Evangelista, Stefano; Gibbons, Simon J.; Szurszewski, Joseph H.

    2010-01-01

    Antispasmodics are used clinically to treat a variety of gastrointestinal disorders by inhibition of smooth muscle contraction. The main pathway for smooth muscle Ca2+ entry is through L-type channels; however, there is increasing evidence that T-type Ca2+ channels also play a role in regulating contractility. Otilonium bromide, an antispasmodic, has previously been shown to inhibit L-type Ca2+ channels and colonic contractile activity. The objective of this study was to determine whether otilonium bromide also inhibits T-type Ca2+ channels. Whole cell currents were recorded by patch-clamp technique from HEK293 cells transfected with cDNAs encoding the T-type Ca2+ channels, CaV3.1 (α1G), CaV3.2 (α1H), or CaV3.3 (α1I) alpha subunits. Extracellular solution was exchanged with otilonium bromide (10−8 to 10−5 M). Otilonium bromide reversibly blocked all T-type Ca2+ channels with a significantly greater affinity for CaV3.3 than CaV3.1 or CaV3.2. Additionally, the drug slowed inactivation in CaV3.1 and CaV3.3. Inhibition of T-type Ca2+ channels may contribute to inhibition of contractility by otilonium bromide. This may represent a new mechanism of action for antispasmodics and may contribute to the observed increased clinical effectiveness of antispasmodics compared with selective L-type Ca2+ channel blockers. PMID:20203058

  11. Mitochondrial carbonic anhydrase CA VB: differences in tissue distribution and pattern of evolution from those of CA VA suggest distinct physiological roles.

    Science.gov (United States)

    Shah, G N; Hewett-Emmett, D; Grubb, J H; Migas, M C; Fleming, R E; Waheed, A; Sly, W S

    2000-02-15

    A cDNA for a second mouse mitochondrial carbonic anhydrase (CA) called CA VB was identified by homology to the previously characterized murine CA V, now called CA VA. The full-length cDNA encodes a 317-aa precursor that contains a 33-aa classical mitochondrial leader sequence. Comparison of products expressed from cDNAs for murine CA VB and CA VA in COS cells revealed that both expressed active CAs that localized in mitochondria, and showed comparable activities in crude extracts and in mitochondria isolated from transfected COS cells. Northern blot analyses of total RNAs from mouse tissues and Western blot analyses of mouse tissue homogenates showed differences in tissue-specific expression between CA VB and CA VA. CA VB was readily detected in most tissues, while CA VA expression was limited to liver, skeletal muscle, and kidney. The human orthologue of murine CA VB was recently reported also. Comparison of the CA domain sequence of human CA VB with that reported here shows that the CA domains of CA VB are much more highly conserved between mouse and human (95% identity) than the CA domains of mouse and human CA VAs (78% identity). Analysis of phylogenetic relationships between these and other available human and mouse CA isozyme sequences revealed that mammalian CA VB evolved much more slowly than CA VA, accepting amino acid substitutions at least 4.5 times more slowly since each evolved from its respective human-mouse ancestral gene around 90 million years ago. Both the differences in tissue distribution and the much greater evolutionary constraints on CA VB sequences suggest that CA VB and CA VA have evolved to assume different physiological roles.

  12. Comparative Research on the Blood IL-6, CK, CK-MM and Ca2+ Changes of Rats after Eccentric Exercise%大鼠急性离心运动后血IL-6、CK、CK-MM和Ca2+变化的比较

    Institute of Scientific and Technical Information of China (English)

    华冰

    2009-01-01

    目的:观察大鼠大强度离心运动后不同时相骨骼肌结构及血IL-6、CK、CK-MM和Ca的变化.方法:40只大鼠分为对照组和运动组,运动组又分为运动后即刻组、24h组、48h组和72h组.运动组完成一次性跑台离心运动.观察各组比目鱼肌结构及血IL-6、CK、CK-MM和Ca的变化.结果①运动后大鼠比目鱼肌出现损伤性改变,运动后24~48h较为严重;②运动后即刻血浆IL-6显著增高.随后逐渐下降,72h再次显著增高;③运动后CK和CK-MM先升后降,但差异不显著;④运动后Ca2+持续降低,显著低于对照组.结论:血浆IL-6可能与由剧烈运动导致的肌肉损伤有关.CK和CK-MM更适用于个体自身的纵向比较.

  13. The Ca(2+ influence on calmodulin unfolding pathway: a steered molecular dynamics simulation study.

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    Full Text Available The force-induced unfolding of calmodulin (CaM was investigated at atomistic details with steered molecular dynamics. The two isolated CaM domains as well as the full-length CaM were simulated in N-C-terminal pulling scheme, and the isolated N-lobe of CaM was studied specially in two other pulling schemes to test the effect of pulling direction and compare with relevant experiments. Both Ca(2+-loaded CaM and Ca(2+-free CaM were considered in order to define the Ca(2+ influence to the CaM unfolding. The results reveal that the Ca(2+ significantly affects the stability and unfolding behaviors of both the isolated CaM domains and the full-length CaM. In Ca(2+-loaded CaM, N-terminal domain unfolds in priori to the C-terminal domain. But in Ca(2+-free CaM, the unfolding order changes, and C-terminal domain unfolds first. The force-extension curves of CaM unfolding indicate that the major unfolding barrier comes from conquering the interaction of two EF-hand motifs in both N- and C- terminal domains. Our results provide the atomistic-level insights in the force-induced CaM unfolding and explain the observation in recent AFM experiments.

  14. Sulfide capacities of CaO-CaF2-CaCl2 melts

    Science.gov (United States)

    Simeonov, Simeon; Sakai, Toshihiko; Maeda, Masafumi

    1992-06-01

    The sulfide capacityC_{s^{2 - } } = ({text{pct S}}^{{text{2 - }}} )(p_{{text{O}}_{text{2}} } /p_{{text{S}}_{text{2}} } )^{1/2} ) of CaO-CaF2-CaCl2 slag was determined at temperatures from 1000 °C to 1300 °C by equilibrating molten slag, molten silver, and CO-CO2-Ar gas mixture. The sulfide capacity increases with replacing CaCl2 by CaF2 in slags of constant CaO contents. The sulfide capacity also increases with increasing temperature as well as with increasing CaO content at a constant ratio of CaF2/CaCl2 of unity. A linear relationship between the sulfide capacity and carbonate capacity in literature was observed on a logarithmic scale.

  15. Protective effects of Ca2+ handling drugs against abnormal Ca2+ homeostasis and cell damage in myopathic skeletal muscle cells.

    Science.gov (United States)

    Iwata, Yuko; Katanosaka, Yuki; Shijun, Zhu; Kobayashi, Yuko; Hanada, Hironori; Shigekawa, Munekazu; Wakabayashi, Shigeo

    2005-09-01

    Deficiency of delta-sarcoglycan (delta-SG), a component of the dystrophin-glycoprotein complex (DGC), causes skeletal muscular dystrophy and cardiomyopathy in BIO14.6 hamsters. Here, we studied the involvement of abnormal Ca2+ homeostasis in muscle degeneration and the protective effect of drugs against Ca2+ handling proteins in vivo as well as in vitro. First, we characterized the properties of cultured myotubes from muscles of normal and BIO14.6 hamsters (30-60 days old). While there were no apparent differences in the levels of expression of various Ca2+ handling proteins (L-type Ca2+ channel, ryanodine receptor, SR-Ca2+ ATPase, and Na+/Ca2+ exchanger), muscle-specific proteins (contractile actin and acetylcholine receptor), or DGC member proteins except SGs, BIO14.6 myotubes showed a high degree of susceptibility to mechanical stressors, such as cyclic stretching and hypo-osmotic stress as compared to normal myotubes, as evidenced by marked increases in creatine phosphokinase (CK) release and bleb formation. BIO14.6 myotubes showed abnormal Ca2+ homeostasis characterized by elevated cytosolic Ca2+ concentration, frequent Ca2+ oscillation, and increased 45Ca2+ uptake. These abnormal Ca2+ events and CK release were significantly prevented by Ca2+ handling drugs, tranilast, diltiazem, and FK506. The calpain inhibitor E64 prevented CK release, but not 45Ca2+ uptake. Some of these drugs (tranilast, diltiazem, and FK506) also exerted a significant protective effect for muscle degeneration in BIO14.6 hamsters and mdx mice in vivo. These observations suggest that elevated Ca2+ entry through sarcolemmal Ca2+ channels predominantly contributes to muscle degeneration and that the drugs tested here may have novel therapeutic potential against muscular dystrophy.

  16. Influence of isolation media on synaptosomal properties: Intracellular pH, pCa, and Ca sup 2+ uptake

    Energy Technology Data Exchange (ETDEWEB)

    Bandeira-Duarte, C.; Carvalho, C.A.; Cragoe Junior, E.J.; Carvalho, A.P. (Univ. of Coimbra (Portugal))

    1990-03-01

    Preparations of synaptosomes isolated in sucrose or in Na(+)-rich media were compared with respect to internal pH (pHi), internal Ca{sup 2+} concentration ((Ca{sup 2+})i), membrane potential and {sup 45}Ca{sup 2+} uptake due to K+ depolarization and Na{sup +}/Ca{sup 2+} exchange. We found that synaptosomes isolated in sucrose media have a pHi of 6.77 +/- 0.04 and a (Ca{sup 2+})i of about 260 nM, whereas synaptosomes isolated in Na(+)-rich ionic media have a pHi of 6.96 +/- 0.07 and a (Ca{sup 2+})i of 463 nM, but both types of preparations have similar membrane potentials of about -50 mV when placed in choline media. The sucrose preparation takes up Ca{sup 2+} only by voltage sensitive calcium channels (VSCC'S) when K(+)-depolarized, while the Na(+)-rich synaptosomes take up {sup 45}Ca{sup 2+} both by VSCC'S and by Na{sup +}/Ca{sup 2+} exchange. The amiloride derivative 2',4'-dimethylbenzamil (DMB), at 30 microM, inhibits both mechanisms of Ca{sup 2+} influx, but 5-(N-4-chlorobenzyl)-2',4' dimethylbenzamil (CBZ-DMB), at 30 microM, inhibits the Ca{sup 2+} uptake by VSCC'S, but not by Na+/Ca2+ exchange. Thus, DMB and CBZ-DMB permit distinguishing between Ca{sup 2+} flux through channels and through Na{sup +}/Ca{sup 2+} exchange. We point out that the different properties of the two types of synaptosomes studied account for some of the discrepancies in results reported in the literature for studies of Ca{sup 2+} fluxes and neurotransmitter release by different types of preparations of synaptosomes.

  17. The prion protein regulates glutamate-mediated Ca(2+) entry and mitochondrial Ca(2+) accumulation in neurons.

    Science.gov (United States)

    De Mario, Agnese; Peggion, Caterina; Massimino, Maria Lina; Viviani, Francesca; Castellani, Angela; Giacomello, Marta; Lim, Dmitry; Bertoli, Alessandro; Sorgato, Maria Catia

    2017-08-15

    The cellular prion protein (PrP(C)) whose conformational misfolding leads to the production of deadly prions, has a still-unclarified cellular function despite decades of intensive research. Following our recent finding that PrP(C) limits Ca(2+) entry via store-operated Ca(2+) channels in neurons, we investigated whether the protein could also control the activity of ionotropic glutamate receptors (iGluRs). To this end, we compared local Ca(2+) movements in primary cerebellar granule neurons and cortical neurons transduced with genetically encoded Ca(2+) probes and expressing, or not expressing, PrP(C) Our investigation demonstrated that PrP(C) downregulates Ca(2+) entry through each specific agonist-stimulated iGluR and after stimulation by glutamate. We found that, although PrP-knockout (KO) mitochondria were displaced from the plasma membrane, glutamate addition resulted in a higher mitochondrial Ca(2+) uptake in PrP-KO neurons than in their PrP(C)-expressing counterpart. This was because the increased Ca(2+) entry through iGluRs in PrP-KO neurons led to a parallel increase in Ca(2+)-induced Ca(2+) release via ryanodine receptor channels. These data thus suggest that PrP(C) takes part in the cell apparatus controlling Ca(2+) homeostasis, and that PrP(C) is involved in protecting neurons from toxic Ca(2+) overloads. © 2017. Published by The Company of Biologists Ltd.

  18. Distribution of interneurons in the CA2 region of the rat hippocampus.

    Science.gov (United States)

    Botcher, Nicola A; Falck, Joanne E; Thomson, Alex M; Mercer, Audrey

    2014-01-01

    The CA2 region of the mammalian hippocampus is a unique region with its own distinctive properties, inputs and pathologies. Disruption of inhibitory circuits in this region appears to be linked with the pathology of specific psychiatric disorders, promoting interest in its local circuitry, its role in hippocampal function and its dysfunction in disease. In previous studies, CA2 interneurons, including a novel subclass of CA2 dendrite-preferring interneurons that has not been identified in other CA regions, have been shown to display physiological, synaptic and morphological properties unique to this sub-field and may therefore play a crucial role in the hippocampal circuitry. The distributions of immuno-labeled interneurons in dorsal CA2 were studied and compared with those of interneurons in CA1 and CA3. Like those in CA1 and CA3, the somata of CA2 parvalbumin-immunoperoxidase-labeled interneurons were located primarily in Stratum Pyramidale (SP) and Stratum Oriens (SO), with very few cells in Stratum Radiatum (SR) and none in Stratum Lacunosum Moleculare (SLM). There was, however, a greater proportion of GAD-positive cells were immunopositive for PV in SP in CA2 than in CA1 or CA3. CA2 SP also contained a larger density of somatostatin-, calbindin-, and VIP-immunopositive somata than CA1 and/or CA3. Like those in CA1 and CA3, CCK-immunopositive somata in CA2 were mostly located in SR. Reelin- and NPY- immunolabeled cell bodies were located in all layers of the three CA regions. However, a higher density of Reelin-positive somata was found in SP and SR of CA2 than in CA1 or CA3.

  19. Ca2+ Influx via the Na+/Ca2+ Exchanger Is Enhanced in Malignant Hyperthermia Skeletal Muscle*

    Science.gov (United States)

    Altamirano, Francisco; Eltit, José M.; Robin, Gaëlle; Linares, Nancy; Ding, Xudong; Pessah, Isaac N.; Allen, Paul D.; López, José R.

    2014-01-01

    Malignant hyperthermia (MH) is potentially fatal pharmacogenetic disorder of skeletal muscle caused by intracellular Ca2+ dysregulation. NCX is a bidirectional transporter that effluxes (forward mode) or influxes (reverse mode) Ca2+ depending on cellular activity. Resting intracellular calcium ([Ca2+]r) and sodium ([Na+]r) concentrations are elevated in MH susceptible (MHS) swine and murine muscles compared with their normal (MHN) counterparts, although the contribution of NCX is unclear. Lowering [Na+]e elevates [Ca2+]r in both MHN and MHS swine muscle fibers and it is prevented by removal of extracellular Ca2+ or reduced by t-tubule disruption, in both genotypes. KB-R7943, a nonselective NCX3 blocker, reduced [Ca2+]r in both swine and murine MHN and MHS muscle fibers at rest and decreased the magnitude of the elevation of [Ca2+]r observed in MHS fibers after exposure to halothane. YM-244769, a high affinity reverse mode NCX3 blocker, reduces [Ca2+]r in MHS muscle fibers and decreases the amplitude of [Ca2+]r rise triggered by halothane, but had no effect on [Ca2+]r in MHN muscle. In addition, YM-244769 reduced the peak and area under the curve of the Ca2+ transient elicited by high [K+]e and increased its rate of decay in MHS muscle fibers. siRNA knockdown of NCX3 in MHS myotubes reduced [Ca2+]r and the Ca2+ transient area induced by high [K+]e. These results demonstrate a functional NCX3 in skeletal muscle whose activity is enhanced in MHS. Moreover reverse mode NCX3 contributes to the Ca2+ transients associated with K+-induced depolarization and the halothane-triggered MH episode in MHS muscle fibers. PMID:24847052

  20. Ca2+ influx via the Na+/Ca2+ exchanger is enhanced in malignant hyperthermia skeletal muscle.

    Science.gov (United States)

    Altamirano, Francisco; Eltit, José M; Robin, Gaëlle; Linares, Nancy; Ding, Xudong; Pessah, Isaac N; Allen, Paul D; López, José R

    2014-07-04

    Malignant hyperthermia (MH) is potentially fatal pharmacogenetic disorder of skeletal muscle caused by intracellular Ca(2+) dysregulation. NCX is a bidirectional transporter that effluxes (forward mode) or influxes (reverse mode) Ca(2+) depending on cellular activity. Resting intracellular calcium ([Ca(2+)]r) and sodium ([Na(+)]r) concentrations are elevated in MH susceptible (MHS) swine and murine muscles compared with their normal (MHN) counterparts, although the contribution of NCX is unclear. Lowering [Na(+)]e elevates [Ca(2+)]r in both MHN and MHS swine muscle fibers and it is prevented by removal of extracellular Ca(2+) or reduced by t-tubule disruption, in both genotypes. KB-R7943, a nonselective NCX3 blocker, reduced [Ca(2+)]r in both swine and murine MHN and MHS muscle fibers at rest and decreased the magnitude of the elevation of [Ca(2+)]r observed in MHS fibers after exposure to halothane. YM-244769, a high affinity reverse mode NCX3 blocker, reduces [Ca(2+)]r in MHS muscle fibers and decreases the amplitude of [Ca(2+)]r rise triggered by halothane, but had no effect on [Ca(2+)]r in MHN muscle. In addition, YM-244769 reduced the peak and area under the curve of the Ca(2+) transient elicited by high [K(+)]e and increased its rate of decay in MHS muscle fibers. siRNA knockdown of NCX3 in MHS myotubes reduced [Ca(2+)]r and the Ca(2+) transient area induced by high [K(+)]e. These results demonstrate a functional NCX3 in skeletal muscle whose activity is enhanced in MHS. Moreover reverse mode NCX3 contributes to the Ca(2+) transients associated with K(+)-induced depolarization and the halothane-triggered MH episode in MHS muscle fibers.

  1. Mitochondrial carbonic anhydrase CA VB: Differences in tissue distribution and pattern of evolution from those of CA VA suggest distinct physiological roles

    OpenAIRE

    Shah, Gul N.; Hewett-Emmett, David; Grubb, Jeffrey H.; Migas, Mary C.; Fleming, Robert E.; Waheed, Abdul; Sly, William S.

    2000-01-01

    A cDNA for a second mouse mitochondrial carbonic anhydrase (CA) called CA VB was identified by homology to the previously characterized murine CA V, now called CA VA. The full-length cDNA encodes a 317-aa precursor that contains a 33-aa classical mitochondrial leader sequence. Comparison of products expressed from cDNAs for murine CA VB and CA VA in COS cells revealed that both expressed active CAs that localized in mitochondria, and showed comparable activities in crude extracts and in mitoc...

  2. Ryanodine Receptor Phosphorylation by CaMKII Promotes Spontaneous Ca2+ Release Events in a Rodent Model of Early Stage Diabetes: the Arrhythmogenic Substrate

    Science.gov (United States)

    Sommese, Leandro; Valverde, Carlos A; Blanco, Paula; Castro, María Cecilia; Rueda, Omar Velez; Kaetzel, Marcia; Dedman, John; Anderson, Mark E.; Mattiazzi, Alicia; Palomeque, Julieta

    2016-01-01

    Background Heart failure and arrhythmias occur more frequently in patients with type 2 diabetes (T2DM) than in the general population. T2DM is preceded by a prediabetic condition marked by elevated reactive oxygen species (ROS) and subclinical cardiovascular defects. Although multifunctional Ca2+ calmodulin-dependent protein kinase II (CaMKII) is ROS-activated and CaMKII hyperactivity promotes cardiac diseases, a link between prediabetes and CaMKII in the heart is unprecedented. Objectives to prove the hypothesis that increased ROS and CaMKII activity contribute to heart failure and arrhythmogenic mechanisms in early stage diabetes. Methods-Results Echocardiography, electrocardiography, biochemical and intracellular Ca2+ (Ca2+i) determinations were performed in fructose-rich diet -induced impaired glucose tolerance, a prediabetes model, in rodents. Fructose-rich diet rats showed decreased contractility and hypertrophy associated with increased CaMKII activity, ROS production, oxidized CaMKII and enhanced CaMKII-dependent ryanodine receptor (RyR2) phosphorylation compared to rats fed with control diet. Isolated cardiomyocytes from fructose-rich diet showed increased spontaneous Ca2+i release events associated with spontaneous contractions, which were prevented by KN-93, a CaMKII inhibitor, or addition of Tempol, a ROS scavenger, to the diet. Moreover, fructose-rich diet myocytes showed increased diastolic Ca2+ during the burst of spontaneous Ca2+i release events. Micetreated with Tempol or with sarcoplasmic reticulum-targeted CaMKII-inhibition by transgenic expression of the CaMKII inhibitory peptide AIP, were protected from fructose-rich diet-induced spontaneous Ca2+i release events, spontaneous contractions and arrhythmogenes is in vivo, despite ROS increases. Conclusions RyR2 phosphorylation by ROS-activated CaMKII, contributes to impaired glucose tolerance-induced arrhythmogenic mechanisms, suggesting that CaMKII inhibition could prevent prediabetic

  3. Parvalbumin is a mobile presynaptic Ca2+ buffer in the calyx of Held that accelerates the decay of Ca2+ and short-term facilitation.

    Science.gov (United States)

    Müller, Martin; Felmy, Felix; Schwaller, Beat; Schneggenburger, Ralf

    2007-02-28

    Presynaptic Ca2+ signaling plays a crucial role in short-term plasticity of synaptic transmission. Here, we studied the role of mobile endogenous presynaptic Ca2+ buffer(s) in modulating paired-pulse facilitation at a large excitatory nerve terminal in the auditory brainstem, the calyx of Held. To do so, we assessed the effect of presynaptic whole-cell recording, which should lead to the diffusional loss of endogenous mobile Ca2+ buffers, on paired-pulse facilitation and on intracellular Ca2+ concentration ([Ca2+]i) transients evoked by action potentials. In unperturbed calyces briefly preloaded with the Ca2+ indicator fura-6F, the [Ca2+]i transient decayed surprisingly fast (tau(fast), approximately 30 ms). Presynaptic whole-cell recordings made without additional Ca2+ buffers slowed the decay kinetics of [Ca2+]i and paired-pulse facilitation (twofold to threefold), but the amplitude of the [Ca2+]i transient was changed only marginally. The fast [Ca2+]i decay was restored by adding the slow Ca2+ buffer EGTA (50-100 microM) or parvalbumin (100 microM), a Ca2+-binding protein with slow Ca2+-binding kinetics, to the presynaptic pipette solution. In contrast, the fast Ca2+ buffer fura-2 strongly reduced the amplitude of the [Ca2+]i transient and slowed its decay, suggesting that the mobile endogenous buffer in calyces of Held has slow, rather than fast, binding kinetics. In parvalbumin knock-out mice, the decay of [Ca2+]i and facilitation was slowed approximately twofold compared with wild-type mice, similar to what is observed during whole-cell recordings in rat calyces of Held. Thus, in young calyces of Held, a mobile Ca2+ buffer with slow binding kinetics, primarily represented by parvalbumin, accelerates the decay of spatially averaged [Ca2+]i and paired-pulse facilitation.

  4. The luminescence of titanite (CaTiSiO5)

    NARCIS (Netherlands)

    Blasse, G.; Dirksen, G.J.; Tanaka, I.; Kojima, H.

    1988-01-01

    The luminescence of CaTiSiO5 crystals is reported. The emission band has its maximum at 520 nm. The results are discussed in connection with titanium compounds containing comparable titanate polyhedra.

  5. Ca(AlH4)2, CaAlH5, and CaH2+6LiBH4: Calculated dehydrogenation enthalpy, including zero point energy, and the structure of the phonon spectra.

    Science.gov (United States)

    Marashdeh, Ali; Frankcombe, Terry J

    2008-06-21

    The dehydrogenation enthalpies of Ca(AlH(4))(2), CaAlH(5), and CaH(2)+6LiBH(4) have been calculated using density functional theory calculations at the generalized gradient approximation level. Harmonic phonon zero point energy (ZPE) corrections have been included using Parlinski's direct method. The dehydrogenation of Ca(AlH(4))(2) is exothermic, indicating a metastable hydride. Calculations for CaAlH(5) including ZPE effects indicate that it is not stable enough for a hydrogen storage system operating near ambient conditions. The destabilized combination of LiBH(4) with CaH(2) is a promising system after ZPE-corrected enthalpy calculations. The calculations confirm that including ZPE effects in the harmonic approximation for the dehydrogenation of Ca(AlH(4))(2), CaAlH(5), and CaH(2)+6LiBH(4) has a significant effect on the calculated reaction enthalpy. The contribution of ZPE to the dehydrogenation enthalpies of Ca(AlH(4))(2) and CaAlH(5) calculated by the direct method phonon analysis was compared to that calculated by the frozen-phonon method. The crystal structure of CaAlH(5) is presented in the more useful standard setting of P2(1)c symmetry and the phonon density of states of CaAlH(5), significantly different to other common complex metal hydrides, is rationalized.

  6. The Expression of CaN and CaMK is Associated with Lipogenesis in the Muscle of Chicken

    Institute of Scientific and Technical Information of China (English)

    Ye YANG; Jiao SONG; Ruiqi FUl; Yanfa SUN; Jie WEN

    2015-01-01

    IntramuscuIar fat (IMF) content in chickens significantIy contributes to meat quality. The maln objective of this study was to assess the expression of calcineurin (CaN) and Ca2+/calmoduIin-dependent protein kinase (CaMK) in Iipogene-sis in chicken muscIe. The chickens were sIaughtered and sampIed at the ages of 4, 8, and 16 weeks, respectiveIy. IMF content and the expression of CaN subunits and CaMK isoforms were measured in thigh muscIe tissue. The resuIts showed that the IMF contents were higher in chickens at the age of 16 weeks compared with those in chickens at the ages of 4 and 8 weeks (P<0.05). The expression IeveIs of fatty acid synthase (FAS) and fatty acid transIocase CD36 (FAT/CD36) mRNA in 16-week-oId chickens were al significantIy up-reguIated compared with those in 4-week-oId chickens (P<0.05). The mRNA IeveIs of CaNB and CaMK IV in 16-week-oId chickens were significantIy Iower than those in 4-week-oId chickens (P<0.05). But the CaMK II mRNA IeveIs in 16-week-oId chickens were significantIy higher than those in 4-week-oId chickens (P<0.05). To investigate the roIes of CaMK and CaN in adipogenesis, SV ceI s were incubated in standard adipogenesis medium for 24 h and treated with specific inhibitor of CaMK and CaN. The ex-pressions of CCAAT/enhancer binding protein β(C/EBPβ), steroI reguIatory eIement-binding protein 1 (SREBP1) and peroxisome proIiferation-activated receptor γ(PPARγ) were dramatical y enhanced by CsA and CaN inhibitor (P<0.05). KN93, a CaMK II inhibitor, dramatical y repressed the expression of those Iipogenic genes (P<0.05). al the resuIts above indicated that CaN and CaMK had different effects on adipogenesis in the muscIe of chickens.

  7. CARCINOMA-ASSOCIATED MUCIN SERUM MARKERS CA-M26 AND CA-M29 - EFFICACY IN DETECTING AND MONITORING PATIENTS WITH CANCER OF THE BREAST, COLON, OVARY, ENDOMETRIUM AND CERVIX

    NARCIS (Netherlands)

    YEDEMA, KA; KENEMANS, P; WOBBES, T; VANKAMP, GJ; DEBRUIJN, HW; THOMAS, CM; MASSUGER, LF; SCHIJF, CP; BON, GG; VERMORKEN, JB; VOORHORST, F; HILGERS, J

    1991-01-01

    Two recently developed monoclonal antibody (MAb)-based anti-mucin assays, CA M26 and CA M29, were studied in 250 cancer patients and compared to 3 well-established marker tests, viz., CA 125, CA 15.3 and SCC, in order to assess their clinical usefulness as serum tumor markers. Pre-treatment sera wer

  8. Ca2+ regulation in the absence of the iplA gene product in Dictyostelium discoideum

    Directory of Open Access Journals (Sweden)

    Happle Kathrin

    2005-03-01

    Full Text Available Abstract Background Stimulation of Dictyostelium discoideum with cAMP evokes an elevation of the cytosolic free Ca2+ concentration ([Ca2+]i. The [Ca2+]i-change is composed of liberation of stored Ca2+ and extracellular Ca2+-entry. The significance of the [Ca2+]i-transient for chemotaxis is under debate. Abolition of chemotactic orientation and migration by Ca2+-buffers in the cytosol indicates that a [Ca2+]i-increase is required for chemotaxis. Yet, the iplA- mutant disrupted in a gene bearing similarity to IP3-receptors of higher eukaryotes aggregates despite the absence of a cAMP-induced [Ca2+]i-transient which favours the view that [Ca2+]i-changes are insignificant for chemotaxis. Results We investigated Ca2+-fluxes and the effect of their disturbance on chemotaxis and development of iplA- cells. Differentiation was altered as compared to wild type amoebae and sensitive towards manipulation of the level of stored Ca2+. Chemotaxis was impaired when [Ca2+]i-transients were suppressed by the presence of a Ca2+-chelator in the cytosol of the cells. Analysis of ion fluxes revealed that capacitative Ca2+-entry was fully operative in the mutant. In suspensions of intact and permeabilized cells cAMP elicited extracellular Ca2+-influx and liberation of stored Ca2+, respectively, yet to a lesser extent than in wild type. In suspensions of partially purified storage vesicles ATP-induced Ca2+-uptake and Ca2+-release activated by fatty acids or Ca2+-ATPase inhibitors were similar to wild type. Mn2+-quenching of fura2 fluorescence allows to study Ca2+-influx indirectly and revealed that the responsiveness of mutant cells was shifted to higher concentrations: roughly 100 times more Mn2+ was necessary to observe agonist-induced Mn2+-influx. cAMP evoked a [Ca2+]i-elevation when stores were strongly loaded with Ca2+, again with a similar shift in sensitivity in the mutant. In addition, basal [Ca2+]i was significantly lower in iplA- than in wild type amoebae

  9. Simulating Urban Growth Using a Random Forest-Cellular Automata (RF-CA Model

    Directory of Open Access Journals (Sweden)

    Courage Kamusoko

    2015-04-01

    Full Text Available Sustainable urban planning and management require reliable land change models, which can be used to improve decision making. The objective of this study was to test a random forest-cellular automata (RF-CA model, which combines random forest (RF and cellular automata (CA models. The Kappa simulation (KSimulation, figure of merit, and components of agreement and disagreement statistics were used to validate the RF-CA model. Furthermore, the RF-CA model was compared with support vector machine cellular automata (SVM-CA and logistic regression cellular automata (LR-CA models. Results show that the RF-CA model outperformed the SVM-CA and LR-CA models. The RF-CA model had a Kappa simulation (KSimulation accuracy of 0.51 (with a figure of merit statistic of 47%, while SVM-CA and LR-CA models had a KSimulation accuracy of 0.39 and −0.22 (with figure of merit statistics of 39% and 6%, respectively. Generally, the RF-CA model was relatively accurate at allocating “non-built-up to built-up” changes as reflected by the correct “non-built-up to built-up” components of agreement of 15%. The performance of the RF-CA model was attributed to the relatively accurate RF transition potential maps. Therefore, this study highlights the potential of the RF-CA model for simulating urban growth.

  10. Novel method of generation of Ca(HCO32 and CaCO3 aerosols and first determination of hygroscopic and cloud condensation nuclei activation properties

    Directory of Open Access Journals (Sweden)

    A. Trimborn

    2010-09-01

    Full Text Available Atmospheric mineral aerosols contain CaCO3 as a reactive component. A novel method to produce CaCO3 aerosol was developed by spraying Ca(HCO32 solution, which was generated from a CaCO3 suspension and CO2. By aerosol mass spectrometry the freshly sprayed and dried aerosol was characterized to consist of pure Ca(HCO32 which under annealing in a tube furnace transformed into CaCO3. Transmission Electron Microscopy demonstrated that the particles produced were spherical. The method was able to generate aerosol of sufficient concentration and proper size for the study of physiochemical properties and investigations of heterogeneous reactions of mineral aerosol. The dried Ca(HCO32 particles were somewhat more hygroscopic than CaCO3 particles. However, during humidification a restructuring took place and ∼2/3 of the Ca(HCO32 was transformed to CaCO3. The mixed Ca(HCO32/CaCO3(s particles were insoluble with a growth factor of 1.03 at 95% (hygroscopicity parameter κ=0.011±0.007 relative humidity. This compares to a corresponding growth factor of 1.01 for CaCO3(s (κ=0.0016±0.0004. Mass spectrometric composition analysis, restructuring, and insolubility of the mixed particles suggested that solid Ca(HCO32(s was observed. This would be in contrast to the current belief that Ca(HCO32(s is thermodynamically instable. The CCN activity of Ca(HCO32(s aerosol (κ≈0.15 is remarkably higher than that of CaCO3 aerosol (κ=0.0019±0.0007 and less than that of Ca(NO32. The noticeable but limited solubility of Ca(HCO32 of ≈0.01 mol/l explains limited hygroscopic growth and good CCN activity. Experiments in the Large Jülich Aerosol Chamber indicated that Ca(HCO32(s could exist for several hours under dry atmospheric conditions. However, it was likely buried in a protective layer of CaCO3(s. We conclude that Ca(HCO32 may be formed in the atmosphere in cloud droplets of activated mineral dust by reaction of CaCO3 with CO2 and H2O. The presence of Ca(HCO32 and

  11. Cenozoic seawater Sr/Ca evolution

    Science.gov (United States)

    Sosdian, Sindia M.; Lear, Caroline H.; Tao, Kai; Grossman, Ethan L.; O'Dea, Aaron; Rosenthal, Yair

    2012-10-01

    Records of seawater chemistry help constrain temporal variations in geochemical processes that impact the global carbon cycle and climate through Earth's history. Here we reconstruct Cenozoic seawater Sr/Ca (Sr/Casw) using fossil Conus and turritellid gastropod Sr/Ca. Combined with an oxygen isotope paleotemperature record from the same samples, the gastropod record suggests that Sr/Caswwas slightly higher in the Eocene (˜11.4 ± 3 mmol/mol) than today (˜8.54 mmol/mol) and remained relatively stable from the mid- to late Cenozoic. We compare our gastropod Cenozoic Sr/Casw record with a published turritellid gastropod Sr/Casw record and other published biogenic (benthic foraminifera, fossil fish teeth) and inorganic precipitate (calcite veins) Sr/Caswrecords. Once the uncertainties with our gastropod-derived Sr/Casw are taken into account the Sr/Casw record agrees reasonably well with biogenic Sr/Caswrecords. Assuming a seawater [Ca] history derived from marine evaporite inclusions, all biogenic-based Sr/Casw reconstructions imply decreasing seawater [Sr] through the Cenozoic, whereas the calcite vein Sr/Casw reconstruction implies increasing [Sr] through the Cenozoic. We apply a simple geochemical model to examine the implications of divergence among these seawater [Sr] reconstructions and suggest that the interpretation and uncertainties associated with the gastropod and calcite vein proxies need to be revisited. Used in conjunction with records of carbonate depositional fluxes, our favored seawater Sr/Ca scenarios point to a significant increase in the proportion of aragonite versus calcite deposition in shelf sediments from the Middle Miocene, coincident with the proliferation of coral reefs. We propose that this occurred at least 10 million years after the seawater Mg/Ca threshold was passed, and was instead aided by declining levels of atmospheric carbon dioxide.

  12. Primary pathways of intracellular Ca(2+) mobilization by nanosecond pulsed electric field.

    Science.gov (United States)

    Semenov, Iurii; Xiao, Shu; Pakhomov, Andrei G

    2013-03-01

    Permeabilization of cell membranous structures by nanosecond pulsed electric field (nsPEF) triggers transient rise of cytosolic Ca(2+) concentration ([Ca(2+)](i)), which determines multifarious downstream effects. By using fast ratiometric Ca(2+) imaging with Fura-2, we quantified the external Ca(2+) uptake, compared it with Ca(2+) release from the endoplasmic reticulum (ER), and analyzed the interplay of these processes. We utilized CHO cells which lack voltage-gated Ca(2+) channels, so that the nsPEF-induced [Ca(2+)](i) changes could be attributed primarily to electroporation. We found that a single 60-ns pulse caused fast [Ca(2+)](i) increase by Ca(2+) influx from the outside and Ca(2+) efflux from the ER, with the E-field thresholds of about 9 and 19kV/cm, respectively. Above these thresholds, the amplitude of [Ca(2+)](i) response increased linearly by 8-10nM per 1kV/cm until a critical level between 200 and 300nM of [Ca(2+)](i) was reached. If the critical level was reached, the nsPEF-induced Ca(2+) signal was amplified up to 3000nM by engaging the physiological mechanism of Ca(2+)-induced Ca(2+)-release (CICR). The amplification was prevented by depleting Ca(2+) from the ER store with 100nM thapsigargin, as well as by blocking the ER inositol-1,4,5-trisphosphate receptors (IP(3)R) with 50μM of 2-aminoethoxydiphenyl borate (2-APB). Mobilization of [Ca(2+)](i) by nsPEF mimicked native Ca(2+) signaling, but without preceding activation of plasma membrane receptors or channels. NsPEF stimulation may serve as a unique method to mobilize [Ca(2+)](i) and activate downstream cascades while bypassing the plasma membrane receptors.

  13. Microstructure, In Vitro Corrosion Behavior and Cytotoxicity of Biodegradable Mg-Ca-Zn and Mg-Ca-Zn-Bi Alloys

    Science.gov (United States)

    Bakhsheshi-Rad, H. R.; Hamzah, E.; Tok, H. Y.; Kasiri-Asgarani, M.; Jabbarzare, S.; Medraj, M.

    2017-02-01

    The effects of bismuth (Bi) addition on the microstructure and corrosion behavior of the Mg-Ca-Zn-Bi alloys were evaluated using electron microscopy, electrochemical test and electrochemical impedance spectroscopy. Microstructural observations showed that Mg-1.2Ca-1Zn- xBi ( x = 0.5, 1.5, 3 wt.%) are composed of Mg2Ca, Ca2Mg6Zn3 and Mg3Bi2 phases while a new phase Mg2Bi2Ca appeared after the addition of 5 and 12 wt.% Bi to the Mg-1.2Ca-1Zn alloy. Furthermore, the additions of 0.5 wt.% Bi to the Mg-1.2Ca-1Zn alloy slightly improved the corrosion behavior of the alloy, while further increase in Bi amount from 1.5 to 12 wt.% has a deleterious effect on the corrosion behavior of the ternary Mg-1.2Ca-1Zn alloy which is driven by galvanic coupling effect. Cytotoxicity tests indicate that the Mg-1.2Ca-1Zn presents higher cell viability compared to Mg-1.2Ca-1Zn-0.5Bi alloy. In addition, the cell viability of both alloys increased with increasing incubation time while diluting the extracts to 50% and 10% improved the cell viabilities. The present results suggest that the Mg-1.2Ca-1Zn-0.5Bi can be interesting candidate for the development of degradable biomaterials and it is worthwhile for further investigation in an in vivo environment.

  14. Bioinformatic analysis of CaBP/calneuron proteins reveals a family of highly conserved vertebrate Ca2+-binding proteins

    Directory of Open Access Journals (Sweden)

    Burgoyne Robert D

    2010-04-01

    Full Text Available Abstract Background Ca2+-binding proteins are important for the transduction of Ca2+ signals into physiological outcomes. As in calmodulin many of the Ca2+-binding proteins bind Ca2+ through EF-hand motifs. Amongst the large number of EF-hand containing Ca2+-binding proteins are a subfamily expressed in neurons and retinal photoreceptors known as the CaBPs and the related calneuron proteins. These were suggested to be vertebrate specific but exactly which family members are expressed outside of mammalian species had not been examined. Findings We have carried out a bioinformatic analysis to determine when members of this family arose and the conserved aspects of the protein family. Sequences of human members of the family obtained from GenBank were used in Blast searches to identify corresponding proteins encoded in other species using searches of non-redundant proteins, genome sequences and mRNA sequences. Sequences were aligned and compared using ClustalW. Some families of Ca2+-binding proteins are known to show a progressive expansion in gene number as organisms increase in complexity. In contrast, the results for CaBPs and calneurons showed that a full complement of CaBPs and calneurons are present in the teleost fish Danio rerio and possibly in cartilaginous fish. These findings suggest that the entire family of genes may have arisen at the same time during vertebrate evolution. Certain members of the family (for example the short form of CaBP1 and calneuron 1 are highly conserved suggesting essential functional roles. Conclusions The findings support the designation of the calneurons as a distinct sub-family. While the gene number for CaBPs/calneurons does not increase, a distinctive evolutionary change in these proteins in vertebrates has been an increase in the number of splice variants present in mammals.

  15. Structural stability of intermetallic compounds of Mg-Al-Ca alloy

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dian-wu; LIU Jin-shui; ZHANG Jian; PENG Ping

    2007-01-01

    A first-principles plane-wave pseudopotential method based on the density functional theory was used to investigate the energetic and electronic structures of intermetallic compounds of Mg-Al-Ca alloy, such as Al2Ca, Al4Ca and Mg2Ca. The negative formation heat, the cohesive energies and Gibbs energies of these compounds were estimated from the electronic structure calculations, and their structural stability was also analyzed. The results show that Al2Ca phase has the strongest alloying ability as well as the highest structural stability, next Al4Ca, finally Mg2Ca. After comparing the density of states of Al2Ca, Al4Ca and Mg2Ca phases, it is found that the highest structural stability of Al2Ca is attributed to an increase in the bonding electron numbers in lower energy range below Fermi level, which mainly originates from the contribution of valence electron numbers of Ca(s) and Ca(p) orbits, while the lowest structural stability of Mg2Ca is resulted from the least bonding electron numbers near Fermi level.

  16. Sonoma County, CA, 2013 Lidar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sonoma County Vegetation Mapping and LiDAR Consortium retained WSI to provide lidar and Orthophoto data and derived products in Sonoma County, CA. A classified LAS...

  17. CA125 in ovarian cancer

    DEFF Research Database (Denmark)

    Duffy, M J; Bonfrer, J M; Kulpa, J

    2005-01-01

    value in the detection of early ovarian cancer. At present, therefore, CA125, either alone or in combination with other modalities, cannot be recommended for screening for ovarian cancer in asymptomatic women outside the context of a randomized controlled trial. Preoperative levels in postmenopausal...... women, however, may aid the differentiation of benign and malignant pelvic masses. Serial levels during chemotherapy for ovarian cancer are useful for assessing response to treatment. Although serial monitoring following initial chemotherapy can lead to the early detection of recurrent disease......CA125 is currently the most widely used tumor marker for ovarian epithelial cancer. The aim of this article is to provide guidelines for the routine clinical use of CA125 in patients with ovarian cancer. Due to lack of sensitivity for stage I disease and lack of specificity, CA125 is of little...

  18. Cathodic behavior of molten CaCl2-CaO and CaCl2-NaCl-CaO

    Science.gov (United States)

    Wang, Shu-Lan; Wang, Wei; Li, Shi-Chao; Cao, Shan-Hui

    2010-12-01

    The cathodic behavior of molten CaCl2, CaCl2-CaO and equimolar CaCl2-NaCl-CaO was studied by cyclic voltammograms and constant potential polarization at temperatures of 1123 to 1173 K on molybdenum and titanium electrodes. The diffusion coefficient of Ca2+ (CaO) in molten CaCl2-CaO was calculated from the linear relationship between the square root of scan rate and the peak current density. The deposition potentials and the potential temperature coefficient of CaO in molten CaCl2-0.5mol%CaO and CaCl2-NaCl-0.5mol%CaO were also obtained from their cyclic voltammograms. The result shows that CaO is more easily reduced than CaCl2. The addition of NaCl in molten CaCl2-CaO induces the underpotential electrodeposition of CaO.

  19. Aerobic Hydrogen Production via Nitrogenase in Azotobacter vinelandii CA6

    Science.gov (United States)

    Noar, Jesse; Loveless, Telisa; Navarro-Herrero, José Luis; Olson, Jonathan W.

    2015-01-01

    The diazotroph Azotobacter vinelandii possesses three distinct nitrogenase isoenzymes, all of which produce molecular hydrogen as a by-product. In batch cultures, A. vinelandii strain CA6, a mutant of strain CA, displays multiple phenotypes distinct from its parent: tolerance to tungstate, impaired growth and molybdate transport, and increased hydrogen evolution. Determining and comparing the genomic sequences of strains CA and CA6 revealed a large deletion in CA6's genome, encompassing genes related to molybdate and iron transport and hydrogen reoxidation. A series of iron uptake analyses and chemostat culture experiments confirmed iron transport impairment and showed that the addition of fixed nitrogen (ammonia) resulted in cessation of hydrogen production. Additional chemostat experiments compared the hydrogen-producing parameters of different strains: in iron-sufficient, tungstate-free conditions, strain CA6's yields were identical to those of a strain lacking only a single hydrogenase gene. However, in the presence of tungstate, CA6 produced several times more hydrogen. A. vinelandii may hold promise for developing a novel strategy for production of hydrogen as an energy compound. PMID:25911479

  20. The Ca II triplet in red giant spectra: [Fe/H] determinations and the role of [Ca/Fe

    CERN Document Server

    Da Costa, G S

    2015-01-01

    Measurements are presented and analyzed of the strength of the Ca II triplet lines in red giants in Galactic globular and open clusters, and in a sample of red giants in the LMC disk that have significantly different [Ca/Fe] abundance ratios to the Galactic objects. The Galactic objects are used to generate a calibration between Ca II triplet line strength and [Fe/H], which is then used to estimate [Fe/H]_CaT for the LMC stars. The values are then compared with the [Fe/H]_spec determinations from high dispersion spectroscopy. After allowance for a small systematic offset the two abundance determinations are in excellent agreement. Further, as found in earlier studies, e.g., Battaglia et al. (2008), the difference is only a very weak function of the [Ca/Fe] ratio. For example, changing [Ca/Fe] from +0.3 to -0.2 causes the Ca II based abundance to underestimate [Fe/H]_spec by only ~0.15 dex, assuming a Galactic calibration. Consequently, the Ca II triplet approach to metallicity determinations can be used witho...

  1. The van der Waals potentials of MgCa, MgSr, MgBa, CaSr, CaBa, and SrBa

    Science.gov (United States)

    Wei, L. M.; Li, P.; Tang, K. T.

    2015-08-01

    Based on the facts that the potential energy curves of the homo-nuclear group 2 dimers (group IIA metal), except Be2, are conformal, and they can be described by the Tang-Toennies potential model, a set of simple combining rules are proposed for the parameters of the reduced potentials of the hetero-nuclear dimers. Together with the well-established combining rules of the range parameters of the exponential repulsion and the known dispersion coefficients, these rules enable us to determine the ground state potential energy curves of MgCa, MgSr, MgBa, CaSr, CaBa, and SrBa from those of Mg2, Ca2, Sr2, and Ba2. The determined potentials are comparable to some ab initio calculations and in excellent agreement with the experiment.

  2. Functional remodeling of Ca2+-activated Cl- channel in pacing induced canine failing heart

    Institute of Scientific and Technical Information of China (English)

    Ning Li; Kejuan Ma; Siyong Teng; Jonathan C.Makielski; Jielin Pu

    2008-01-01

    Objective To determine whether Ca2+ activated Cl- current(Icl(Ca)) contributes to the functional remodeling of the failing heart.Methods Whole cell patch-clamp recording technique was employed to record the Icl(Ca) in cardiac myocytes enzymatically isolatedfrom rapidly pacing induced canine failing hearts at room temperature and compared that of the normal hearts (Nor).Results Thecurrent density of DIDS(200M)sensitive Icl(Ca) induced by intracellular Ca2+ release trigged by L-type Ca2+ current(Ica,L)wassignificantly decreased in heart failare(HE)cells compared to Nor cells.At membrane voltage of 20mV,the Icl(Ca) density was 3.02±0.54 pA/pF in Nor(n=6)vs.1.31±0.25 pA/pF in HF(n=8)cells,(P<0.01),while the averaged Ica,L density did not show differencebetween two groups.The time constant of current decay of Icl(Ca) was similar in both types of cells.On the other hand,in intra cellularCa2+ clamped mode,where the[Ca2+];was maintained at 100nmol/L,Icl(Ca) density be increased significantly in HF cells when themembrane voltage at+30mV or higher.Conclusions Our results suggest that Icl(Ca) density was decreased in pacing induced failingheart but the channel function be enhanced.Impaired Ca2+ handing in HF cells rather than reduced,Icl(Ca) channel function itself may havecaused this abnormality.The Icl(Ca) density reduction might contribute to the prolongation of action potential in failing heart.The Icl(Ca)channel function up-rugulation is likely to cause cardiac arrhythmia by inducing a delayed after depolarization,when Ca2+ overloadoccurred in diastolic failing heart cells.

  3. Prenatal morphine exposure reduces pyramidal neurons in CA1, CA2 and CA3 subfields of mice hippocampus

    Directory of Open Access Journals (Sweden)

    Soraya Ghafari

    2014-03-01

    Full Text Available Objective(s:This study was carried out to evaluate the effect of maternal morphine exposure during gestational and lactation period on pyramidal neurons of hippocampus in 18 and 32 day mice offspring. Materials and Methods: Thirty female mice were randomly allocated into cases and controls. In case group, animals received morphinesulfate 10 mg/kg.body weight intraperitoneally during 7 days before mating, gestational period (GD 0-21, 18 and 32 days after delivery in the experimental groups. The control animals received an equivalent volume of normal saline. Cerebrum of six offsprings in each group was removed and stained with cresyl violet and a monoclonal antibody NeuN for immunohistochemical detection of surviving pyramidal neurons. Quantitative computer-assisted morphometric study was done on hippocampus. Results: The number of pyramidal neurons in CA1, CA2 and CA3 in treated groups was significantly reduced in postnatal day 18 and 32 (P18, P32 compared to control groups (P

  4. Temperature and Ca2+-dependence of the sarcoplasmic reticulum Ca2(+)-ATPase in haddock, salmon, rainbow trout and zebra cichlid

    DEFF Research Database (Denmark)

    Godiksen, Helene; Jessen, Flemming

    2002-01-01

    in the enzyme or its membrane lipid environment is still a matter of discussion. In this study we compared the temperature dependence and Ca2+-dependence of SR Ca2+-ATPase in haddock (Melanogrammus aeglefinus), salmon (Salmo, salar), rainbow trout (Oncorhynchus mykiss) and zebra cichlid (Cichlasoma...... nigrofasciatum). The Arrhenius plot of zebra cichlid showed a break point at 20 degreesC, and the haddock Arrhenius plot was non-linear with pronounced changes in slope in the. temperature area, 6-14 degreesC. In Arrhenius plot from both salmon and rainbow trout a plateau exists with an almost constant SR Ca2...

  5. A comparative study of low-field magnetoresistance for La sub 2 sub / sub 3 Ca sub 1 sub / sub 3 Mn sub 1 sub - sub x Cu sub x O sub 3 (x = 0% and 4%) synthesized at different temperatures

    CERN Document Server

    Yuan, S L; Xia, Z C; Zhao, L F; Liu, L; Chen, W; Zhang, G H; Zhang, L J; Feng, W; Zhong, Q H; Liu, S

    2003-01-01

    Polycrystalline samples of nominal La sub 2 sub / sub 3 Ca sub 1 sub / sub 3 Mn sub 1 sub - sub x Cu sub x O sub 3 (x 0% and 4%) were fabricated by a sol-gel method following sintering treatments at temperature T sub s ranging between 1000 deg. C and 1300 deg. C. Experiments indicate that doping Cu does not cause a change in crystalline structure, but strongly affects transport and magnetoresistance (MR) properties. For lower T sub s , when a low magnetic field of H = 0.3 T, is applied, the x = 0 samples show typical intergrain MR behaviour with a monotonic increase in MR sub 0 (ident to DELTA rho/rho(H = 0)) on cooling; while for the x = 4% samples, in addition to intergrain MR, a characteristic feature similar to colossal MR (CMR) is observed near the insulator-metal transition. The maximum MR with a value approx 80% of that for H = 0.3 T is obtained in the sample prepared at 1100 deg. C, which is comparable to the intrinsic CMR response usually observed in large fields of the order of several teslas.

  6. The analysis of serum CEA、CA125、CA199 in 174 patients with cancer%肿瘤患者血清中癌胚抗原、癌相关糖抗原125和199的检测结果分析

    Institute of Scientific and Technical Information of China (English)

    姚辉盛; 翁克丽

    2012-01-01

    Objective Discussion of patients with tumor of three kinds of serum tumor markers CEA, CA12-5 and CA19 -9 level changes, and in tumor assisted diagnosis application value Methods Using a chemiluminescence immune assay for the detection of particles in 60 cases with coloreclal cancer, 25 cases of patients with lung cancer, 40 cases of gastric cancer, 15 cases of patients with esophageal cancer, 18 cases of bladder carcinoma, 16 cases of cervical esophageal carcinoma patients and 50 healthy people 3 tumor markers in serum level. Results Colorectal cancer, lung cancer and gastric cancer patients with 3 kinds of serum tumor markers levels and positive rates were significantly higher than those in healthy people group (P<0. 01), there was a significant difference; in patients with cervical cancer CAI25 levels and positive rates were significantly higher than those in healthy group (P <0. 01), there was a significant difference. Conclusions 3 kinds of serum tumor markers for tumor diagnosis is of certain clinical value, the positive rate of combined detection is more higher, bladder cancer, esophageal cancer and cervical cancer patients should be combined with clinical symptoms, operation and pathology examination.%目的 探讨肿瘤患者血清中肿瘤标志物癌胚抗原(CEA)、癌相关糖抗原125和199水平的变化及其在肿瘤辅助诊断中的应用价值.方法 采用化学发光微粒免疫分析法检测60例结直肠癌患者、25例肺癌患者、40例胃癌患者、15例食管癌患者、18例膀胱癌患者、16例宫颈癌患者和50例健康人血清中CEA、CA12 -5和CA19 -9的水平.结果 结直肠癌、肺癌和胃癌患者的CEA、CA12 -5和CA19 -9水平及阳性率均明显高于对照组,差异有统计学意义(P<0.01);宫颈癌患者CA125水平及阳性率均明显高于对照组,差异有统计学意义(P<0.01).结论 CEA、CA12 -5和CA19 -9对于肿瘤的辅助诊断有一定的临床参考价值,联合检测的阳性率更高,膀

  7. Fabrication and characterization of CaP-coated nanotube arrays

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Kuan-Chen; Chen, Jia-Ling [Institute of Oral Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Liu, Yen-Ting [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan (China); Lee, Tzer-Min, E-mail: tmlee@mail.ncku.edu.tw [Institute of Oral Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Medical Device Innovation Center, National Cheng Kung University, Tainan 701, Taiwan (China); School of Dentistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China)

    2015-03-01

    Modified anodization techniques have been shown to improve the biocompatibility of titanium. This study demonstrated the anodic formation of self-organized nanotube arrays on titanium from an electrolyte solution containing 1 M H{sub 3}PO{sub 4} and 1 wt% hydrofluoric acid (HF). Our aim was to investigate the effects of sputter-deposited CaP on nanotube arrays. SEM images revealed a surface with uniform morphology and an average pore diameter of 29 nm. XRD results indicated that the phase of the nanotube arrays was amorphous. Electron spectroscopy for chemical analysis (ESCA) confirmed that the nanotube arrays were coated with calcium and phosphorus. Cell culture experiments using human osteosarcoma (HOS) cells demonstrated that the CaP/nanotube arrays had a pronounced effect on initial cell attachment as well as on the number of cells at 1, 7, and 14 days. Compared to as-polished titanium, the CaP/nanotube arrays accelerated cell proliferation, attachment, and spreading. Our results demonstrate the pronounced effects of CaP/nanotube arrays on the biological responses of HOS cells. - Highlights: • Self-organized nanotube arrays were anodically formed on titanium. • Surfaces of nanotube arrays exhibited uniform morphology and pore size. • According to ESCA results, Ca and P were successfully coated on nanotube arrays. • CaP/nanotube arrays accelerated the attachment and spreading of cells. • CaP/nanotube arrays were shown to affect biological responses of cells.

  8. In vitro degradation and cytotoxicity of Mg/Ca composites produced by powder metallurgy.

    Science.gov (United States)

    Zheng, Y F; Gu, X N; Xi, Y L; Chai, D L

    2010-05-01

    Mg/Ca (1 wt.%, 5 wt.%, 10 wt.% Ca) composites were prepared from pure magnesium and calcium powders using the powder metallurgy method, aiming to enlarge the addition of Ca content without the formation of Mg(2)Ca. The microstructures, mechanical properties and cytotoxicities of Mg/Ca composite samples were investigated. The corrosion of Mg/Ca composites in Dulbecco's modified Eagle's medium (DMEM) for various immersion intervals was studied by electrochemical impedance spectroscopy measurements and environmental scanning electron microscope, with the concentrations of released Mg and Ca ions in DMEM for various immersion time intervals being measured. It was shown that the main constitutional phases were Mg and Ca, which were uniformly distributed in the Mg matrix. The ultimate tensile strength (UTS) and elongation of experimental composites decreased with increasing Ca content, and the UTS of Mg/1Ca composite was comparable with that of as-extruded Mg-1Ca alloy. The corrosion potential increased with increasing Ca content, whereas the current density and the impedance decreased. It was found that the protective surface film formed quickly at the initial immersion stage. With increasing immersion time, the surface film became compact, and the corrosion rate of Mg/Ca composites slowed down. The surface film consisted mainly of CaCO(3), MgCO(3)x3H(2)O, HA and Mg(OH)(2) after 72 h immersion in DMEM. Mg/1Ca and Mg/5Ca composite extracts had no significant toxicity (p>0.05) to L-929 cells, whereas Mg/10Ca composite extract induced approximately 40% reduced cell viability.

  9. Development of Ca2+ hotspots between Lymnaea neurons during synaptogenesis.

    Science.gov (United States)

    Feng, Zhong-Ping; Grigoriev, Nikita; Munno, David; Lukowiak, Ken; MacVicar, Brian A; Goldberg, Jeffrey I; Syed, Naweed I

    2002-02-15

    Calcium (Ca2+) channel clustering at specific presynaptic sites is a hallmark of mature synapses. However, the spatial distribution patterns of Ca2+ channels at newly formed synapses have not yet been demonstrated. Similarly, it is unclear whether Ca2+ 'hotspots' often observed at the presynaptic sites are indeed target cell contact specific and represent a specialized mechanism by which Ca2+ channels are targeted to select synaptic sites. Utilizing both soma-soma paired (synapsed) and single neurons from the mollusk Lymnaea, we have tested the hypothesis that differential gradients of voltage-dependent Ca2+ signals develop in presynaptic neuron at its contact point with the postsynaptic neuron; and that these Ca2+ hotspots are target cell contact specific. Fura-2 imaging, or two-photon laser scanning microscopy of Calcium Green, was coupled with electrophysiological techniques to demonstrate that voltage-induced Ca2+ gradients (hotspots) develop in the presynaptic cell at its contact point with the postsynaptic neuron, but not in unpaired single cells. The incidence of Ca2+ hotspots coincided with the appearance of synaptic transmission between the paired cells, and these gradients were target cell contact specific. In contrast, the voltage-induced Ca2+ signal in unpaired neurons was uniformly distributed throughout the somata; a similar pattern of Ca2+ gradient was observed in the presynaptic neuron when it was soma-soma paired with a non-synaptic partner cell. Moreover, voltage clamp recording techniques, in conjunction with a fast, optical differential perfusion system, were used to demonstrate that the total whole-cell Ca2+ (or Ba2+) current density in single and paired cells was not significantly different. However, the amplitude of Ba2+ current was significantly higher in the presynaptic cell at its contact side with the postsynaptic neurons, compared with non-contacted regions. In summary, this study demonstrates that voltage-induced Ca2+ hotspots develop

  10. The site of net absorption of Ca from the intestinal tract of growing pigs and effect of phytic acid, Ca level and Ca source on Ca digestibility.

    Science.gov (United States)

    González-Vega, J Caroline; Walk, Carrie L; Liu, Yanhong; Stein, Hans H

    2014-01-01

    An experiment was conducted to test the hypothesis that the standardised digestibility of Ca in calcium carbonate and Lithothamnium calcareum Ca is not different regardless of the level of dietary Ca, and that phytic acid affects the digestibility of Ca in these two ingredients to the same degree. The objectives were to determine where in the intestinal tract Ca absorption takes place and if there are measurable quantities of basal endogenous Ca fluxes in the stomach, small intestine or large intestine. Diets contained calcium carbonate or L. calcareum Ca as the sole source of Ca, 0% or 1% phytic acid and 0.4% or 0.8% Ca. A Ca-free diet was also formulated and used to measure endogenous fluxes and losses of Ca. Nine growing pigs (initial body weight 23.8 ± 1.3 kg) were cannulated in the duodenum and in the distal ileum, and faecal, ileal and duodenal samples were collected. Duodenal endogenous fluxes of Ca were greater (p phytic acid, but decreased (p phytic acid, but may be affected by dietary Ca level depending on the Ca source. Calcium from calcium carbonate is mostly absorbed before the duodenum, but Ca from L. calcareum Ca is mostly absorbed in the jejunum and ileum.

  11. CA on CD评析

    Institute of Scientific and Technical Information of China (English)

    周秀会

    2007-01-01

    结合作者使用 CA On CD 的经验和体会,全面而具体地分析了 CA on CD 的使用功能,明确了其优点及不足之处,同时,针对这些不足之处进行了探索和尝试,提出了利用检索技巧解决这些不足之处的方法。并结合实例详细说明。

  12. First-principles simulations of CaO and CaSiO3 liquids: structure, thermodynamics and diffusion

    Science.gov (United States)

    Bajgain, Suraj K.; Ghosh, Dipta B.; Karki, Bijaya B.

    2015-05-01

    We have performed first-principles molecular dynamics simulations of CaO and CaSiO3 liquids over broad ranges of pressure (0-150 GPa) and temperature (2,500-8,000 K) within density-functional theory. The simulated liquid structure changes considerably on compression with the mean cation-anion coordination numbers increasing nearly linearly with volume. The Ca-O coordination number increases from 5 (7) near the ambient pressure to 8 (10) at high pressure for CaO (CaSiO3) liquid. The Si-O coordination number increases from 4 to 6 over the same pressure regime. Our results show that both liquids are much more compressible than their solid counterparts implying the possibility of liquid-solid density crossovers at high pressure. The Grüneisen parameter of both the liquids increases with pressure, which is opposite in case of crystalline phases. The calculated self-diffusion coefficients strongly depend on temperature and pressure, thereby requiring non-Arrhenian representation with variable activation volume. The diffusivity differences between the two liquids tend to be large at low-temperature and low-pressure regime. Also, comparisons with MgSiO3 liquid suggest that network modifier cations Ca and Mg behave similarly though Ca is more coordinated and more mobile as compared to Mg.

  13. CaV3.2 Channels and the Induction of Negative Feedback in Cerebral Arteries

    Science.gov (United States)

    Harraz, Osama F.; Abd El-Rahman, Rasha R.; Bigdely-Shamloo, Kamran; Wilson, Sean M.; Brett, Suzanne E.; Romero, Monica; Gonzales, Albert L.; Earley, Scott; Vigmond, Edward J.; Nygren, Anders; Menon, Bijoy K.; Mufti, Rania E.; Watson, Tim; Starreveld, Yves; Furstenhaupt, Tobias; Muellerleile, Philip R.; Kurjiaka, David T.; Kyle, Barry D.; Braun, Andrew P.; Welsh, Donald G.

    2015-01-01

    Rationale T-type (CaV3.1/CaV3.2) Ca2+ channels are expressed in rat cerebral arterial smooth muscle. Although present, their functional significance remains uncertain with findings pointing to a variety of roles. Objective This study tested whether CaV3.2 channels mediate a negative feedback response by triggering Ca2+ sparks, discrete events that initiate arterial hyperpolarization by activating large-conductance Ca2+-activated K+ channels. Methods and Results Micromolar Ni2+, an agent that selectively blocks CaV3.2 but not CaV1.2/CaV3.1, was first shown to depolarize/constrict pressurized rat cerebral arteries; no effect was observed in CaV3.2−/− arteries. Structural analysis using 3-dimensional tomography, immunolabeling, and a proximity ligation assay next revealed the existence of microdomains in cerebral arterial smooth muscle which comprised sarcoplasmic reticulum and caveolae. Within these discrete structures, CaV3.2 and ryanodine receptor resided in close apposition to one another. Computational modeling revealed that Ca2+ influx through CaV3.2 could repetitively activate ryanodine receptor, inducing discrete Ca2+-induced Ca2+ release events in a voltage-dependent manner. In keeping with theoretical observations, rapid Ca2+ imaging and perforated patch clamp electrophysiology demonstrated that Ni2+ suppressed Ca2+ sparks and consequently spontaneous transient outward K+ currents, large-conductance Ca2+-activated K+ channel mediated events. Additional functional work on pressurized arteries noted that paxilline, a large-conductance Ca2+-activated K+ channel inhibitor, elicited arterial constriction equivalent, and not additive, to Ni2+. Key experiments on human cerebral arteries indicate that CaV3.2 is present and drives a comparable response to moderate constriction. Conclusions These findings indicate for the first time that CaV3.2 channels localize to discrete microdomains and drive ryanodine receptor–mediated Ca2+ sparks, enabling large

  14. Seawater nutrient and carbonate ion concentrations recorded as P/Ca, Ba/Ca, and U/Ca in the deep-sea coral Desmophyllum dianthus

    Science.gov (United States)

    Anagnostou, Eleni; Sherrell, Robert M.; Gagnon, Alex; LaVigne, Michele; Field, M. Paul; McDonough, William F.

    2011-05-01

    As paleoceanographic archives, deep sea coral skeletons offer the potential for high temporal resolution and precise absolute dating, but have not been fully investigated for geochemical reconstructions of past ocean conditions. Here we assess the utility of skeletal P/Ca, Ba/Ca and U/Ca in the deep sea coral D. dianthus as proxies of dissolved phosphate (remineralized at shallow depths), dissolved barium (trace element with silicate-type distribution) and carbonate ion concentrations, respectively. Measurements of these proxies in globally distributed D. dianthus specimens show clear dependence on corresponding seawater properties. Linear regression fits of mean coral Element/Ca ratios against seawater properties yield the equations: P/Ca coral (μmol/mol) = (0.6 ± 0.1) P/Ca sw(μmol/mol) - (23 ± 18), R2 = 0.6, n = 16 and Ba/Ca coral(μmol/mol) = (1.4 ± 0.3) Ba/Ca sw(μmol/mol) + (0 ± 2), R2 = 0.6, n = 17; no significant relationship is observed between the residuals of each regression and seawater temperature, salinity, pressure, pH or carbonate ion concentrations, suggesting that these variables were not significant secondary dependencies of these proxies. Four D. dianthus specimens growing at locations with Ωarag ⩽ 0.6 displayed markedly depleted P/Ca compared to the regression based on the remaining samples, a behavior attributed to an undersaturation effect. These corals were excluded from the calibration. Coral U/Ca correlates with seawater carbonate ion: U/Ca coral(μmol/mol) = (-0.016 ± 0.003) [CO32-] (μmol/kg) + (3.2 ± 0.3), R2 = 0.6, n = 17. The residuals of the U/Ca calibration are not significantly related to temperature, salinity, or pressure. Scatter about the linear calibration lines is attributed to imperfect spatial-temporal matches between the selected globally distributed specimens and available water column chemical data, and potentially to unresolved additional effects. The uncertainties of these initial proxy calibration regressions

  15. Isotopic Effects on Stereodynamics for Ca+HCI, Ca+DCI, and Ca+TClReactions

    Institute of Scientific and Technical Information of China (English)

    Li-zhi Wang; Chuan-lu Yang; Jing-juan Liang; Jing Xiao; Qing-gang Zhang

    2011-01-01

    The vector correlations in Ca+HC1,Ca+DCI,and Ca+TCI reactions have been investigated by means of the quasi-classical trajectory calculations on PES constructed by means of multireference configuration interaction.The distributions of P(θr),P(Φr) and the PDDCSs of (2π/σ)(dσ00/dωt),(2π/σ)(dσ20/dωt),(2π/σ)(dσ22+/dωt),(2π/σ)(dσ21-/dωt) have been calculated based on the surface.The remarkable isotopic effects in the reactions are observed,and the mechanism which may be ascribed to different mass factors is discussed.

  16. Solar Ca II K Observations

    Science.gov (United States)

    Bertello, Luca; Pevtsov, Alexei A.; Tlatov, Andrey; Singh, Jagdev

    2016-07-01

    Some of the most important archives of past and current long-term solar synoptic observations in the resonance line of Ca II K are described here. These observations are very important for understanding the state of the solar magnetism on time scales up to several decades. The first observations of this kind began in 1904 at the Kodaikanal Observatory (India), followed by similar programs at different other locations. Regular full-disk Ca II K monitoring programs started in 1915 at the Mount Wilson Observatory (USA) and in 1917 at the National Solar Observatory of Japan. Beginning in 1919 and in 1926 regular observations were taken also at the Paris-Meudon Observatory (France) and at the "Donati solar tower telescope of the Arcetri Astrophysical Observatory in Italy, respectively. In 1926 the the Astronomical Observatory of the Coimbra University in Portugal started its own program of Ca II K observations. Although some of these programs have been terminated over the years, their data archives constitute a unique resource for studies of solar variability. In the early 1970s, the National Solar Observatory (NSO) at Sacramento Peak (USA) started a new program of daily Sun-as-a-star observations in the Ca II K line. Today the NSO is continuing these observations through its Synoptic Optical Long-term Investigations of the Sun (SOLIS) facility.

  17. EMRE Is a Matrix Ca(2+) Sensor that Governs Gatekeeping of the Mitochondrial Ca(2+) Uniporter.

    Science.gov (United States)

    Vais, Horia; Mallilankaraman, Karthik; Mak, Don-On Daniel; Hoff, Henry; Payne, Riley; Tanis, Jessica E; Foskett, J Kevin

    2016-01-26

    The mitochondrial uniporter (MCU) is an ion channel that mediates Ca(2+) uptake into the matrix to regulate metabolism, cell death, and cytoplasmic Ca(2+) signaling. Matrix Ca(2+) concentration is similar to that in cytoplasm, despite an enormous driving force for entry, but the mechanisms that prevent mitochondrial Ca(2+) overload are unclear. Here, we show that MCU channel activity is governed by matrix Ca(2+) concentration through EMRE. Deletion or charge neutralization of its matrix-localized acidic C terminus abolishes matrix Ca(2+) inhibition of MCU Ca(2+) currents, resulting in MCU channel activation, enhanced mitochondrial Ca(2+) uptake, and constitutively elevated matrix Ca(2+) concentration. EMRE-dependent regulation of MCU channel activity requires intermembrane space-localized MICU1, MICU2, and cytoplasmic Ca(2+). Thus, mitochondria are protected from Ca(2+) depletion and Ca(2+) overload by a unique molecular complex that involves Ca(2+) sensors on both sides of the inner mitochondrial membrane, coupled through EMRE.

  18. Characterization of the ER-Targeted Low Affinity Ca2+ Probe D4ER

    Directory of Open Access Journals (Sweden)

    Elisa Greotti

    2016-09-01

    Full Text Available Calcium ion (Ca2+ is a ubiquitous intracellular messenger and changes in its concentration impact on nearly every aspect of cell life. Endoplasmic reticulum (ER represents the major intracellular Ca2+ store and the free Ca2+ concentration ([Ca2+] within its lumen ([Ca2+]ER can reach levels higher than 1 mM. Several genetically-encoded ER-targeted Ca2+ sensors have been developed over the last years. However, most of them are non-ratiometric and, thus, their signal is difficult to calibrate in live cells and is affected by shifts in the focal plane and artifactual movements of the sample. On the other hand, existing ratiometric Ca2+ probes are plagued by different drawbacks, such as a double dissociation constant (Kd for Ca2+, low dynamic range, and an affinity for the cation that is too high for the levels of [Ca2+] in the ER lumen. Here, we report the characterization of a recently generated ER-targeted, Förster resonance energy transfer (FRET-based, Cameleon probe, named D4ER, characterized by suitable Ca2+ affinity and dynamic range for monitoring [Ca2+] variations within the ER. As an example, resting [Ca2+]ER have been evaluated in a known paradigm of altered ER Ca2+ homeostasis, i.e., in cells expressing a mutated form of the familial Alzheimer’s Disease-linked protein Presenilin 2 (PS2. The lower Ca2+ affinity of the D4ER probe, compared to that of the previously generated D1ER, allowed the detection of a conspicuous, more clear-cut, reduction in ER Ca2+ content in cells expressing mutated PS2, compared to controls.

  19. Depleted internal store-activated Ca2+ entry can trigger neurotransmitter release in bovine chromaffin cells.

    Science.gov (United States)

    Powis, D A; Clark, C L; O'Brien, K J

    1996-02-09

    A potential role of the intracellular Ca2+ stores in modulating catecholamine release has been investigated in bovine chromaffin cells maintained in tissue culture. Pharmacological depletion of the stores with a combination of caffeine, histamine and thapsigargin in Ca2+-free media resulted in a significantly greater release of catecholamines on re-exposure to Ca2+-containing media compared with that from non-store depleted cells. The increase in catecholamine release was prevented by intracellular BAPTA indicating that the increase was caused by a rise in Ca2+. Measurement of intracellular free Ca2+ concentration with the fluorescent indicator, fura-2, over the same time-course as the catecholamine release experiments showed that upon restoration of external Ca2+ there was an immediate, substantial and maintained increase in cytosolic Ca2+. It is most probable that the increase in catecholamine release was a consequence of an increase in Ca2+ influx triggered by prior depletion of the internal Ca2+ stores. However, the data suggest that capacitative Ca2+ entry is poorly linked to catecholamine release; although Ca2+ entry on restoration of external Ca2+ was immediate and substantial, the increase in catecholamine release, although quantitatively significant, was slowly realised.

  20. 肿瘤标志物CA 153、CA 125检验在肺癌诊断中的应用价值%Application Value of Tumor Marker CA 153 and CA 125 Test in Diagnosis of Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    郜玲

    2016-01-01

    Objective To study tumor markers CA 153, application value of CA 125 test in the diagnosis of lung cancer.Methods A recently admitted to our hospital in patients with lung cancer 46 cases and the same period in our hospital, 50 cases of patients with benign lesions as the object of study, were compared the two kinds of CA 153 and CA 125 changes.Results The cancer sign abnormal rate of CA 153, CA 125 level were higher than benign lesion, P<0.05, was difference had statistically significance.Conclusion The diagnosis of lung cancer patients, the serum CA 153 and CA 125 detection of tumor markers is helpful to improve the diagnostic accuracy of lung cancer patients.%目的:研究分析肿瘤标志物CA 153、CA 125检验在肺癌诊断中的应用价值。方法我院近期收治的肺癌患者46例以及同期我院收治的50例良性病变患者作为研究对象,分别比较这两类人员CA 153以及CA 125的变化情况。结果癌症患者肿瘤标志物CA 153以及CA 125检测水平异常率均高于良性病变人群,P<0.05,差异有统计学意义。结论对于肺癌患者的诊断中,通过对患者血清CA 153以及CA 125肿瘤标志物的检测,有助于提高肺癌患者的诊断准确率。

  1. New mucin-like cancer-associated antigens (CA M 26, CA M 29 and CA 549) and a new proliferation marker (TPS) in patients with primary or advanced breast cancer.

    Science.gov (United States)

    Locker, G J; Mader, R M; Braun, J; Sieder, A E; Marosi, C; Rainer, H; Jakesz, R; Steger, G G

    1995-01-01

    In patients with breast cancer no tumor markers giving satisfactory results have been found yet. The aim of our investigation was to compare the usefulness of newly developed tumor markers with the most common used carcinoembryonic antigen and cancer antigen (CA) 15-3. We evaluated the concentrations of carcinoma-associated antigen (CA) 549, carcinoma-associated mucin antigen (CA M) 26 and CA M 29, and the proliferation markers tissue polypeptide antigen (TPA) and tissue polypeptide-specific antigen (TPS) in 84 breast cancer patients with disease progression and in 69 patients with no evidence of disease after surgery for breast cancer. Using receiver-operating characteristic curves (ROC curves) we were able to demonstrate increased sensitivity and specificity of all tested tumor markers in patients with metastatic disease compared with local disease. In our investigation TPA is superior to TPS in all disease states. In local disease, none of the tested markers shows satisfying results. In metastatic disease, the new mucin markers CA M 26 and CA M 29 show slightly better results than CA 15-3 although their ROC curves are nearly congruent. CA 549 is exceeded by the other mucin markers. The best results in this investigation were obtained with CA M 29. The overall results concerning the detection of small tumor masses (i.e. local disease) were unsatisfactory.

  2. Ca2+ and endoplasmic reticulum Ca2+-ATPase regulate the formation of silk fibers with favorable mechanical properties.

    Science.gov (United States)

    Wang, Xin; Li, Yi; Xie, Kang; Yi, Qiying; Chen, Quanmei; Wang, Xiaohuan; Shen, Hong; Xia, Qingyou; Zhao, Ping

    2015-02-01

    Calcium ions (Ca(2+)) are crucial for the conformational transition of silk fibroin in vitro, and silk fibroin conformations correlate with the mechanical properties of silk fibers. To investigate the relationship between Ca(2+) and mechanical properties of silk fibers, CaCl2 was injected into silkworms (Bombyx mori). Fourier-transform infrared spectroscopy (FTIR) analysis and mechanical testing revealed that injection of CaCl2 solution (7.5mg/g body weight) significantly increased the levels of α-helix and random coil structures of silk proteins. In addition, extension of silk fibers increased after CaCl2 injection. In mammals, sarcoplasmic reticulum Ca(2+)-ATPase in muscle and endoplasmic reticulum Ca(2+)-ATPase in other tissues (together denoted by SERCA) are responsible for calcium balance. Therefore, we analyzed the expression pattern of silkworm SERCA (BmSERCA) in silk glands and found that BmSERCA was abundant in the anterior silk gland (ASG). After injection of thapsigargin (TG) to block SERCA activity, silkworms showed a silk-spinning deficiency and their cocoons had higher calcium content compared to that of controls. Moreover, FTIR analysis revealed that the levels of α-helix and β-sheet structures increased in silk fibers from TG-injected silkworms compared to controls. The results provide evidence that BmSERCA has a key function in calcium transportation in ASG that is related to maintaining a suitable ionic environment. This ionic environment with a proper Ca(2+) concentration is crucial for the formation of silk fibers with favorable mechanical performances.

  3. KWU-werkersklasdramas in Afrikaans (ca. 1930 - ca. 1950

    Directory of Open Access Journals (Sweden)

    J. L. Coetser

    1999-05-01

    Full Text Available GWU working class theatre in Afrikaans (ca. 1930 - ca. 1950In 1984 Elsabé Brink drew attention to plays, prose and poetry written between 1930 and 1950 in Afrikaans by members of the Garment Workers’ Union (GWU. Scholars such as Stander and Willemse (1992, Van Niekerk (1996 and Van Wyk (1995, 1997 have also referred to GWU plays. Apart from these overviews, GWU plays as such have not yet received the attention they deserve. This article presents a revaluation, initially by providing an overview of their contents, followed by an examination of cultural, economic and political influences. It is argued that - retrospectively - the GWU plays reflected a unique cultural specificity from the framework established by Sitas (1986 for more contemporary working class theatre.

  4. Ca2+ dynamics in zebrafish morphogenesis

    Directory of Open Access Journals (Sweden)

    Yusuke Tsuruwaka

    2017-01-01

    Full Text Available Intracellular calcium ion (Ca2+ signaling is heavily involved in development, as illustrated by the use of a number of Ca2+ indicators. However, continuous Ca2+ patterns during morphogenesis have not yet been studied using fluorescence resonance energy transfer to track the Ca2+ sensor. In the present study, we monitored Ca2+ levels during zebrafish morphogenesis and differentiation with yellow cameleon, YC2.12. Our results show not only clear changes in Ca2+ levels but also continuous Ca2+ patterns at 24 hpf and later periods for the first time. Serial Ca2+dynamics during early pharyngula period (Prim-5-20; 24–33 hpf was successfully observed with cameleon, which have not reported anywhere yet. In fact, high Ca2+ level occurred concurrently with hindbrain development in segmentation and pharyngula periods. Ca2+ patterns in the late gastrula through segmentation periods which were obtained with cameleon, were similar to those obtained previously with other Ca2+sensor. Our results suggested that the use of various Ca2+ sensors may lead to novel findings in studies of Ca2+ dynamics. We hope that these results will prove valuable for further research in Ca2+ signaling.

  5. Mechanical, thermal, and physical properties of Mg-Ca compounds in the framework of the modified embedded-atom method.

    Science.gov (United States)

    Groh, Sébastien

    2015-02-01

    Interatomic potentials for pure Ca and the Mg-Ca binary have been developed in the framework of the second nearest-neighbors modified embedded-atom method (MEAM). The validity and the transferability of the Ca MEAM potential was performed by calculating physical, mechanical, and thermal properties. These properties were compared to experimental data and numerical data obtained from existing Ca potentials, and a good agreement was found. In addition, the dissociation of the edge dislocation into two Shockley partials aligns with the linear elasticity solution. Furthermore, the velocity of an edge dislocation under static and dynamics loading conditions predicted in Ca using the MEAM formalism reproduces the expected behavior of an edge dislocation in fcc crystal structures. The Ca MEAM potential was then coupled to an existing Mg MEAM potential to describe the properties of the Mg-Ca alloys. Heat of formation, structural energy difference, and elastic constants were calculated for several ordered Mg-Ca compounds containing different concentrations of Ca. As expected from first-principle calculations based on DFT, Mg2Ca with the Laves phase C14 was found to be the most stable structure with the lowest heat of formation compared to compounds with other Ca concentrations (Mg3Ca, MgCa, and MgCa3). Moreover, the mechanical stability was recovered for the different tested compounds and is in agreement with first-principle data.

  6. Effects of cumene hydroperoxide on the Ca(2+)-induced Ca2+ efflux from mitochondria and on the viability of hepatoma cells.

    Science.gov (United States)

    Teplova, V V; Kudin, A P; Evtodienko YuV

    1998-01-01

    Effects of cumene hydroperoxide on the Ca(2+)-induced Ca2+ efflux from mitochondria isolated from rat liver and Zaidelja hepatoma were compared. Cumene hydroperoxide at micromolar concentrations (0.3-10 microM) prevented the closing of the permeability transition pore in the inner mitochondrial membrane and, therefore, potentiated the Ca(2+)-induced Ca2+ efflux. This response was 10-100 times greater in hepatoma mitochondria than in rat liver mitochondria. Micromolar concentrations of cumene hydroperoxide induced the death of the hepatoma cells in vitro.

  7. Ca2+-permeable and Ca2+-impermeable AMPA receptors coexist on horizontal cells.

    Science.gov (United States)

    Huang, Shi-Yong; Liang, Pei-Ji

    2005-02-28

    Fura-2 fluorescent calcium imaging was used for analyzing the subtype of AMPA receptors in freshly dissociated horizontal cells of carp retina. Exogenous application of AMPA induced an increase of intracellular concentration of free Ca2+ ([Ca2+]i) in horizontal cells, while the [Ca2+]i increase was partly inhibited by nifedipine. The residual [Ca2+]i increase was completely eliminated by joro spider toxin-3, a blocker of Ca2+-permeable AMPA receptors. On the other hand, the application of pentobarbital, which blocked Ca2+-impermeable AMPA receptors, could also partly inhibit the increase of [Ca2+]i, implying that the application of AMPA induced the activation of both Ca2+-permeable and Ca2+-impermeable AMPA receptors and the consequent activation of voltage-gated Ca2+ channels. Taken together, these results suggested that Ca2+-permeable and Ca2+-impermeable AMPA receptors were coexpressed on horizontal cells.

  8. Ca2+ influx through L-type Ca2+ channels and Ca2+-induced Ca2+ release regulate cAMP accumulation and Epac1-dependent ERK 1/2 activation in INS-1 cells.

    Science.gov (United States)

    Pratt, Evan P S; Salyer, Amy E; Guerra, Marcy L; Hockerman, Gregory H

    2016-01-05

    We previously reported that INS-1 cells expressing the intracellular II-III loop of the L-type Ca(2+) channel Cav1.2 (Cav1.2/II-III cells) are deficient in Ca(2+)-induced Ca(2+) release (CICR). Here we show that glucose-stimulated ERK 1/2 phosphorylation (GSEP) is slowed and reduced in Cav1.2/II-III cells compared to INS-1 cells. This parallels a decrease in glucose-stimulated cAMP accumulation (GS-cAMP) in Cav1.2/II-III cells. Influx of Ca(2+) via L-type Ca(2+) channels and CICR play roles in both GSEP and GS-cAMP in INS-1 cells since both are inhibited by nicardipine or ryanodine. Further, the Epac1-selective inhibitor CE3F4 abolishes glucose-stimulated ERK activation in INS-1 cells, as measured using the FRET-based sensor EKAR. The non-selective Epac antagonist ESI-09 but not the Epac2-selective antagonist ESI-05 nor the PKA antagonist Rp-cAMPs inhibits GSEP in both INS-1 and Cav1.2/II-III cells. We conclude that L-type Ca(2+) channel-dependent cAMP accumulation, that's amplified by CICR, activates Epac1 and drives GSEP in INS-1 cells.

  9. Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences

    Science.gov (United States)

    Koho, Karoliina A.; de Nooijer, Lennart J.; Fontanier, Christophe; Toyofuku, Takashi; Oguri, Kazumasa; Kitazato, Hiroshi; Reichart, Gert-Jan

    2017-06-01

    The Mn / Ca of calcium carbonate tests of living (rose-Bengal-stained) benthic foraminifera (Elphidium batialis, Uvigerina spp., Bolivina spissa, Nonionellina labradorica and Chilostomellina fimbriata) were determined in relation to pore water manganese (Mn) concentrations for the first time along a bottom water oxygen gradient across the continental slope along the NE Japan margin (western Pacific). The local bottom water oxygen (BWO) gradient differs from previous field study sites focusing on foraminiferal Mn / Ca and redox chemistry, therefore allowing further resolution of previously observed trends. The Mn / Ca ratios were analysed using laser ablation inductively coupled plasma-mass spectrometer (ICP-MS), allowing single-chamber determination of Mn / Ca. The incorporation of Mn into the carbonate tests reflects environmental conditions and is not influenced by ontogeny. The inter-species variability in Mn / Ca reflected foraminiferal in-sediment habitat preferences and associated pore water chemistry but also showed large interspecific differences in Mn partitioning. At each station, Mn / Ca ratios were always lower in the shallow infaunal E. batialis, occupying relatively oxygenated sediments, compared to intermediate infaunal species, Uvigerina spp. and B. spissa, which were typically found at greater depth, under more reducing conditions. The highest Mn / Ca was always recorded by the deep infaunal species N. labradorica and C. fimbriata. Our results suggest that although partitioning differs, Mn / Ca ratios in the intermediate infaunal taxa are promising tools for palaeoceanographic reconstructions as their microhabitat exposes them to higher variability in pore water Mn, thereby making them relatively sensitive recorders of redox conditions and/or bottom water oxygenation.

  10. Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences

    Directory of Open Access Journals (Sweden)

    K. A. Koho

    2017-06-01

    Full Text Available The Mn / Ca of calcium carbonate tests of living (rose-Bengal-stained benthic foraminifera (Elphidium batialis, Uvigerina spp., Bolivina spissa, Nonionellina labradorica and Chilostomellina fimbriata were determined in relation to pore water manganese (Mn concentrations for the first time along a bottom water oxygen gradient across the continental slope along the NE Japan margin (western Pacific. The local bottom water oxygen (BWO gradient differs from previous field study sites focusing on foraminiferal Mn / Ca and redox chemistry, therefore allowing further resolution of previously observed trends. The Mn / Ca ratios were analysed using laser ablation inductively coupled plasma-mass spectrometer (ICP-MS, allowing single-chamber determination of Mn / Ca. The incorporation of Mn into the carbonate tests reflects environmental conditions and is not influenced by ontogeny. The inter-species variability in Mn / Ca reflected foraminiferal in-sediment habitat preferences and associated pore water chemistry but also showed large interspecific differences in Mn partitioning. At each station, Mn / Ca ratios were always lower in the shallow infaunal E. batialis, occupying relatively oxygenated sediments, compared to intermediate infaunal species, Uvigerina spp. and B. spissa, which were typically found at greater depth, under more reducing conditions. The highest Mn / Ca was always recorded by the deep infaunal species N. labradorica and C. fimbriata. Our results suggest that although partitioning differs, Mn / Ca ratios in the intermediate infaunal taxa are promising tools for palaeoceanographic reconstructions as their microhabitat exposes them to higher variability in pore water Mn, thereby making them relatively sensitive recorders of redox conditions and/or bottom water oxygenation.

  11. Effects of Anthopleurin-Q on the Intracellular Free Ca2+ Concentration in Cultured Rat Cortical Astrocytes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To investigate the effect of anthopleurin-Q (AP-Q) on the intracellular Ca2+ concentration ([Ca2+ ]i) in cultured cortical astrocytes of rats. Methods: The [Ca2+ ]i was monitored by calcium imaging with Ca2+ sensitive fluorescent probe fura-2. Results: A concentration of 300 nmol/L AP-Q increased the [Ca2+ ]i in astrocytes by (136.98%±35.63%) (n=28),when compared with the baseline level. Furthermore, the elevation of [Ca2+]i was prevented by extracellular calcium free solution or when the extracellular Na+ was replaced by NMDG+ , and was decreased by Ni+ ,a non-specific antagonist of Na+/Ca2+ exchanger. Conclusion: AP-Q induced the intracellular [Ca2+ ]i elevation in cultured rat cortical astrocytes via activating the reverse mode of Na+/Ca2+ exchanger. AP-Q may be a useful tool to develop experimental model of seizures.

  12. Lattice Dynamics of fcc Ca

    DEFF Research Database (Denmark)

    Stassis, C.; Zaretsky, J.; Misemer, D. K.;;

    1983-01-01

    to the propagation of elastic waves. The frequencies of the T1[ξξ0] branch for ξ between approximately 0.5 and 0.8 are slightly above the velocity-of-sound line determined from the low-frequency measurements. Since a similar effect has been observed in FCC Yb, it is natural to assume that the anomalous dispersion......A large single crystal of FCC Ca was grown and was used to study the lattice dynamics of this divalent metal by coherent inelastic neutron scattering. The phonon dispersion curves were measured, at room temperature, along the [ξ00], [ξξ0], [ξξξ], and [0ξ1] symmetry directions. The dispersion curves...... bear a striking resemblance to those of FCC Yb, which is also a divalent metal with an electronic band structure similar to that of Ca. In particular, the shear moduli c44 and (c11-c 12)/2 differ by a factor of 3.4, which implies that FCC Ca (like FCC Yb) is very anisotropic with regard...

  13. Continuously Tunable Ca2+ Regulation of RNA-Edited CaV1.3 Channels

    Directory of Open Access Journals (Sweden)

    Hojjat Bazzazi

    2013-10-01

    Full Text Available CaV1.3 ion channels are dominant Ca2+ portals into pacemaking neurons, residing at the epicenter of brain rhythmicity and neurodegeneration. Negative Ca2+ feedback regulation of CaV1.3 channels (CDI is therefore critical for Ca2+ homeostasis. Intriguingly, nearly half the CaV1.3 transcripts in the brain are RNA edited to reduce CDI and influence oscillatory activity. It is then mechanistically remarkable that this editing occurs precisely within an IQ domain, whose interaction with Ca2+-bound calmodulin (Ca2+/CaM is believed to induce CDI. Here, we sought the mechanism underlying the altered CDI of edited channels. Unexpectedly, editing failed to attenuate Ca2+/CaM binding. Instead, editing weakened the prebinding of Ca2+-free CaM (apoCaM to channels, which proves essential for CDI. Thus, editing might render CDI continuously tunable by fluctuations in ambient CaM, a prominent effect we substantiate in substantia nigral neurons. This adjustability of Ca2+ regulation by CaM now looms as a key element of CNS Ca2+ homeostasis.

  14. Inhibition of the sarcoplasmic reticulum Ca2+ pump with thapsigargin to estimate the contribution of Na+-Ca2+ exchange to ventricular myocyte relaxation

    Directory of Open Access Journals (Sweden)

    Bassani R.A.

    2003-01-01

    Full Text Available Relaxation in the mammalian ventricle is initiated by Ca2+ removal from the cytosol, which is performed by three main transport systems: sarcoplasmic reticulum Ca2+-ATPase (SR-A, Na+-Ca2+ exchanger (NCX and the so-called slow mechanisms (sarcolemmal Ca2+-ATPase and mitochondrial Ca2+ uptake. To estimate the relative contribution of each system to twitch relaxation, SR Ca2+ accumulation must be selectively inhibited, usually by the application of high caffeine concentrations. However, caffeine has been reported to often cause changes in membrane potential due to NCX-generated inward current, which compromises the reliability of its use. In the present study, we estimated integrated Ca2+ fluxes carried by SR-A, NCX and slow mechanisms during twitch relaxation, and compared the results when using caffeine application (Cf-NT and an electrically evoked twitch after inhibition of SR-A with thapsigargin (TG-TW. Ca2+ transients were measured in 20 isolated adult rat ventricular myocytes with indo-1. For transients in which one or more transporters were inhibited, Ca2+ fluxes were estimated from the measured free Ca2+ concentration and myocardial Ca2+ buffering characteristics. NCX-mediated integrated Ca2+ flux was significantly higher with TG-TW than with Cf-NT (12 vs 7 µM, whereas SR-dependent flux was lower with TG-TW (77 vs 81 µM. The relative participations of NCX (12.5 vs 8% with TG-TW and Cf-NT, respectively and SR-A (85 vs 89.5% with TG-TW and Cf-NT, respectively in total relaxation-associated Ca2+ flux were also significantly different. We thus propose TG-TW as a reliable alternative to estimate NCX contribution to twitch relaxation in this kind of analysis.

  15. Ablation of NMDA receptors enhances the excitability of hippocampal CA3 neurons.

    Directory of Open Access Journals (Sweden)

    Fumiaki Fukushima

    Full Text Available Synchronized discharges in the hippocampal CA3 recurrent network are supposed to underlie network oscillations, memory formation and seizure generation. In the hippocampal CA3 network, NMDA receptors are abundant at the recurrent synapses but scarce at the mossy fiber synapses. We generated mutant mice in which NMDA receptors were abolished in hippocampal CA3 pyramidal neurons by postnatal day 14. The histological and cytological organizations of the hippocampal CA3 region were indistinguishable between control and mutant mice. We found that mutant mice lacking NMDA receptors selectively in CA3 pyramidal neurons became more susceptible to kainate-induced seizures. Consistently, mutant mice showed characteristic large EEG spikes associated with multiple unit activities (MUA, suggesting enhanced synchronous firing of CA3 neurons. The electrophysiological balance between fast excitatory and inhibitory synaptic transmission was comparable between control and mutant pyramidal neurons in the hippocampal CA3 region, while the NMDA receptor-slow AHP coupling was diminished in the mutant neurons. In the adult brain, inducible ablation of NMDA receptors in the hippocampal CA3 region by the viral expression vector for Cre recombinase also induced similar large EEG spikes. Furthermore, pharmacological blockade of CA3 NMDA receptors enhanced the susceptibility to kainate-induced seizures. These results raise an intriguing possibility that hippocampal CA3 NMDA receptors may suppress the excitability of the recurrent network as a whole in vivo by restricting synchronous firing of CA3 neurons.

  16. UCP3 Regulates Single-Channel Activity of the Cardiac mCa1.

    Science.gov (United States)

    Motloch, Lukas J; Gebing, Tina; Reda, Sara; Schwaiger, Astrid; Wolny, Martin; Hoppe, Uta C

    2016-08-01

    Mitochondrial Ca(2+) uptake (mCa(2+) uptake) is thought to be mediated by the mitochondrial Ca(2+) uniporter (MCU). UCP2 and UCP3 belong to a superfamily of mitochondrial ion transporters. Both proteins are expressed in the inner mitochondrial membrane of the heart. Recently, UCP2 was reported to modulate the function of the cardiac MCU related channel mCa1. However, the possible role of UCP3 in modulating cardiac mCa(2+) uptake via the MCU remains inconclusive. To understand the role of UCP3, we analyzed cardiac mCa1 single-channel activity in mitoplast-attached single-channel recordings from isolated murine cardiac mitoplasts, from adult wild-type controls (WT), and from UCP3 knockout mice (UCP3(-/-)). Single-channel registrations in UCP3(-/-) confirmed a murine voltage-gated Ca(2+) channel, i.e., mCa1, which was inhibited by Ru360. Compared to WT, mCa1 in UCP3(-/-) revealed similar single-channel characteristics. However, in UCP3(-/-) the channel exhibited decreased single-channel activity, which was insensitive to adenosine triphosphate (ATP) inhibition. Our results suggest that beyond UCP2, UCP3 also exhibits regulatory effects on cardiac mCa1/MCU function. Furthermore, we speculate that UCP3 might modulate previously described inhibitory effects of ATP on mCa1/MCU activity as well.

  17. Fine tuning of cytosolic Ca 2+ oscillations

    Science.gov (United States)

    Dupont, Geneviève; Combettes, Laurent

    2016-01-01

    Ca 2+ oscillations, a widespread mode of cell signaling, were reported in non-excitable cells for the first time more than 25 years ago. Their fundamental mechanism, based on the periodic Ca 2+ exchange between the endoplasmic reticulum and the cytoplasm, has been well characterized. However, how the kinetics of cytosolic Ca 2+ changes are related to the extent of a physiological response remains poorly understood. Here, we review data suggesting that the downstream targets of Ca 2+ are controlled not only by the frequency of Ca 2+ oscillations but also by the detailed characteristics of the oscillations, such as their duration, shape, or baseline level. Involvement of non-endoplasmic reticulum Ca 2+ stores, mainly mitochondria and the extracellular medium, participates in this fine tuning of Ca 2+ oscillations. The main characteristics of the Ca 2+ exchange fluxes with these compartments are also reviewed. PMID:27630768

  18. [Effect of polycarbophil Ca on IBS].

    Science.gov (United States)

    Mine, Tetsuya

    2006-08-01

    In this chapter, I mentioned the effect of polycarbophil Ca on IBS. IBS is classified into 3 types; diarrhea type, constipation type and combined type. Polycarbophil Ca is effective for all types of IBS.

  19. Characterization of EhCaBP, a calcium-binding protein of Entamoeba histolytica and its binding proteins.

    Science.gov (United States)

    Yadava, N; Chandok, M R; Prasad, J; Bhattacharya, S; Sopory, S K; Bhattacharya, A

    1997-01-01

    A novel calcium-binding protein (EhCaBP) has been recently identified and characterized from the protozoan parasite Entamoeba histolytica. In order to decipher the function of this protein, a few basic properties were investigated and compared with the ubiquitous Ca(2+)-signal transducing protein calmodulin (CaM). Indirect immunofluorescence and immunoprecipitation analyses using specific antibodies against EhCaBP suggest that it is a soluble cytoplasmic protein with no major post-translational modification. EhCaBP did not stimulate cAMP-phosphodiesterase activity, differentiating it from all known CaMs. Affinity chromatography of [35S]methionine-labelled proteins of E. histolytica trophozoites using EhCaBP-sepharose column showed Ca(2+)-dependent binding of a group of proteins. Radiolabelled proteins from the same extract also bound to CaM-sepharose. However, the proteins bound to the two columns were different as revealed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. At least one of the EhCaBP-binding proteins became phosphorylated as revealed by in vivo phosphorylation analysis. The binding-proteins could not be detected in E. invadens (a species that is pathogenic in reptiles) and E. moshkovskii (which is found in the human gut but is not pathogenic), two species in which EhCaBP-like protein has not been found. Two distinct Ca(2+)-dependent protein kinases, which get activated by EhCaBP and CaM respectively, were detected in E. histolytica. These kinases require different levels of Ca2+ for their maximal activities. Affinity chromatography also showed the binding of protein kinase(s) to EhCaBP in a Ca(2+)-dependent manner. Our data suggest that there may be novel Ca(2+)-signal transduction pathway in E. histolytica mediated by EhCaBP.

  20. Barnacle muscle: Ca2+, activation and mechanics.

    Science.gov (United States)

    Ashley, C C; Griffiths, P J; Lea, T J; Mulligan, I P; Palmer, R E; Simnett, S J

    1993-01-01

    In this review, aspects of the ways in which Ca2+ is transported and regulated within muscle cells have been considered, with particular reference to crustacean muscle fibres. The large size of these fibres permits easy access to the internal environment of the cell, allowing it to be altered by microinjection or microperfusion. At rest, Ca2+ is not in equilibrium across the cell membrane, it enters the cell down a steep electrochemical gradient. The free [Ca2+] at rest is maintained at a value close to 200 nM by a combination of internal buffering systems, mainly the SR, mitochondria, and the fixed and diffusible Ca(2+)-binding proteins, as well as by an energy-dependent extrusion system operating across the external cell membrane. This system relies upon the inward movement of Na+ down its own electrochemical gradient to provide the energy for the extrusion of Ca2+ ions. As a result of electrical excitation, voltage-sensitive channels for Ca2+ are activated and permit Ca2+ to enter the cell more rapidly than at rest. It has been possible to determine both the amount of Ca2+ entering by this step, and what part this externally derived Ca2+ plays in the development of force as well as in the free Ca2+ change. The latter can be determined directly by Ca(2+)-sensitive indicators introduced into the cell sarcoplasm. A combination of techniques, allowing both the total and free Ca2+ changes to be assessed during electrical excitation, has provided valuable information as to how muscle cells buffer their Ca2+ in order to regulate the extent of the change in the free Ca2+ concentration. The data indicate that the entering Ca2+ can only make a small direct contribution to the force developed by the cell. The implication here is that the major source of Ca2+ for contraction must be derived from the internal Ca2+ storage sites within the SR system, a view reinforced by caged Ca2+ methods. The ability to measure the free Ca2+ concentration changes within a single cell during

  1. Comparing Concurrent Chemoradiotherapy to Chemotherapy Alone for Locally Advanced Unresectable Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Hoon; Kim, Woo Chul; Kim, Hun Jung; Gwak, Hee Keun [Inha University Hospital, Incheon (Korea, Republic of)

    2009-06-15

    Concurrent chemoradiotherapy (CCRT) is the standard treatment for locally advanced unresectable pancreatic cancer. However, the introduction of gemcitabine and the recognition of a benefit in patients with advanced disease stimulated the design of trials that compare chemotherapy alone to concurrent chemoradiation. Therefore, we evaluated role of CCRT for locally advanced unresectable pancreatic cancer. We carried out a retrospective analysis of treatment results for patients with locally advanced unresectable pancreatic cancer between January 2000 and January 2008. The radiation was delivered to the primary tumor and regional lymph nodes with a 1{approx}2 cm margin at a total dose of 36.0{approx}59.4 Gy (median: 54 Gy). The chemotherapeutic agent delivered with the radiation was 5-FU (500 mg/m{sup 2}). The patients who underwent chemotherapy alone received gemcitabine (1,000 mg/m{sup 2}) alone or gemcitabine with 5-FU. The follow-up period ranged from 2 to 38 months. The survival and prognostic factors were analyzed using Kaplan-Meier method and log-rank test, respectively. Thirty-four patients received concurrent chemoradiotherapy, whereas 21 patients received chemotherapy alone. The median survival time was 12 months for CCRT patients, compared to 11 months for chemotherapy alone patients (p=0.453). The median progression-free survival was 8 months for CCRT patients, compared to 5 months for chemotherapy alone patients (p=0.242). The overall response included 9 partial responses for CCRT and 1 partial response for chemotherapy alone. In total, 26% of patients from the CCRT group experienced grade 3{approx}4 bowel toxicity. In contract, no grade 3{approx}4 bowel toxicity was observed in the chemotherapy alone group. The significant prognostic factors of overall survival were lymph node status, high CA19-9, and tumor location. The response rate and progression-free survival were more favorable in the CCRT group, when compared with the chemotherapy alone group

  2. CA-CA互操作研究%Research of CA-CA Interoperability

    Institute of Scientific and Technical Information of China (English)

    沈士根; 叶培松; 陈宝明

    2005-01-01

    文章介绍了国际上CA-CA之间实现互操作的信任模式,然后根据中国目前的PKI实际情况,提出了以桥CA为全局模式,局部可采用严格层次信任模式来实现各CA之间的互操作.

  3. 45Ca uptake from water by snails (Lymnaea vulgaris) in control and detergent-polluted samples.

    Science.gov (United States)

    Misra, V; Lal, H; Viswanathan, P N; Murti, C R

    1984-02-01

    A biostatic assay method involving 45Ca uptake into shells and tissues of snails (Lymnaea vulgaris) in 72 hr was developed to follow the effect of detergent-polluted water on ecosystems. There was a marked decrease in the 45Ca uptake by shells and tissues of linear alkyl benzene sulfonate-exposed animals as compared to controls. No change in 45Ca uptake was observed in dead shells, thereby excluding the possibility of passive exchange.

  4. An inhibitory effect of extracellular Ca2+ on Ca2+-dependent exocytosis.

    Directory of Open Access Journals (Sweden)

    Wei Xiong

    Full Text Available AIM: Neurotransmitter release is elicited by an elevation of intracellular Ca(2+ concentration ([Ca(2+](i. The action potential triggers Ca(2+ influx through Ca(2+ channels which causes local changes of [Ca(2+](i for vesicle release. However, any direct role of extracellular Ca(2+ (besides Ca(2+ influx on Ca(2+-dependent exocytosis remains elusive. Here we set out to investigate this possibility on rat dorsal root ganglion (DRG neurons and chromaffin cells, widely used models for studying vesicle exocytosis. RESULTS: Using photolysis of caged Ca(2+ and caffeine-induced release of stored Ca(2+, we found that extracellular Ca(2+ inhibited exocytosis following moderate [Ca(2+](i rises (2-3 µM. The IC(50 for extracellular Ca(2+ inhibition of exocytosis (ECIE was 1.38 mM and a physiological reduction (∼30% of extracellular Ca(2+ concentration ([Ca(2+](o significantly increased the evoked exocytosis. At the single vesicle level, quantal size and release frequency were also altered by physiological [Ca(2+](o. The calcimimetics Mg(2+, Cd(2+, G418, and neomycin all inhibited exocytosis. The extracellular Ca(2+-sensing receptor (CaSR was not involved because specific drugs and knockdown of CaSR in DRG neurons did not affect ECIE. CONCLUSION/SIGNIFICANCE: As an extension of the classic Ca(2+ hypothesis of synaptic release, physiological levels of extracellular Ca(2+ play dual roles in evoked exocytosis by providing a source of Ca(2+ influx, and by directly regulating quantal size and release probability in neuronal cells.

  5. CORRELATION OF {sup 48}Ca, {sup 50}Ti, AND {sup 138}La HETEROGENEITY IN THE ALLENDE REFRACTORY INCLUSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hsin-Wei; Lee, Typhoon; Lee, Der-Chuen; Chen, Jiang-Chang, E-mail: hart.chen@bristol.ac.uk [Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, ROC (China)

    2015-06-10

    Precise determinations of {sup 48}Ca anomalies in Allende calcium–aluminum-rich inclusions (CAIs) are reported in this work. There are endemic positive {sup 48}Ca/{sup 44}Ca anomalies in all analyzed CAIs after normalization to {sup 42}Ca/{sup 44}Ca, and it is clearly shown that there is no simple correlation between {sup 48}Ca/{sup 44}Ca and {sup 50}Ti/{sup 48}Ti anomalies, in agreement with Jungck et al. Compared to the {sup 48}Ca/{sup 44}Ca versus {sup 50}Ti/{sup 48}Ti correlation line defined by differentiated meteorites, reported by Chen et al., the CAIs plot to elevated {sup 50}Ti/{sup 48}Ti. Assuming the {sup 48}Ca/{sup 44}Ca anomalies of both CAIs and differentiated meteorites came from the same source, excess {sup 50}Ti anomalies in CAIs can be calculated by subtracting the part associated with {sup 48}Ca/{sup 44}Ca. These excesses show a linear correlation with {sup 138}La anomalies, a neutrino-process nuclide. According to current stellar nucleosynthetic models, we therefore suggest that the solar system {sup 48}Ca, {sup 50}Ti, and {sup 138}La isotopic variations are made of mixtures between grains condensed from ejecta of neutron-rich accretion-induced SNe Ia and the O/Ne–O/C zone of core-collapse SNe II.

  6. Energetics of ternary nitrides: Li-Ca-Zn-N and Ca-Ta-N systems

    Energy Technology Data Exchange (ETDEWEB)

    McHale, J.M.; Navrotsky, A. [Princeton Univ., NJ (United States); Kowach, G.R.; Balbarin, V.E.; DiSalvo, F.J. [Cornell Univ., Ithaca, NY (United States)

    1997-07-01

    High-temperature oxide melt drop solution calorimetry was used to study the energetics of ternary nitride formation. The standard enthalpies of formation of several binary and ternary nitrides were determined. These values in kJ mol{sup {minus}1} are {Delta}H{sub f}{degrees}(Li{sub 3}N) = {minus}166.1 {+-} 4.8, {Delta}H{sub f}{degrees}(Ca{sub 3}N{sub 2}) = 439.7{+-} 6.6, {Delta}H{sub f}{degrees}(Zn{sub 3}N{sub 2}) = 43.5 {+-} 4.1, {Delta}H{sub f}{degrees}(Ta{sub 3}N{sub 5}) = 849.7 {+-} 11.7, {Delta}H{sub f}{degrees}(Ca{sub 2}ZnN{sub 2}) = {minus}378.9 {+-} 8.6, {Delta}H{sub f}{degrees}(Sr{sub 2}ZnN{sub 2}) = {minus}385.6 {+-} 14.3, {Delta}H{sub f}{degrees}(LiCaN) = {minus}216.8 {+-} 10.8, {Delta}H{sub f}{degrees}(LiZnN) = {minus}137.5 {+-} 6.8, and {Delta}H{sub f}{degrees}(CaTaN{sub 2}) = 1643.8 {+-} 9.6. These enthalpies of formation are small in magnitude compared to analogous values for oxides. However, the enthalpies of formation of the ternaries from binary nitrides can be quite substantial, confirming significant energetic stabilization of ternary nitrides. The energetics of ternary nitride formation appears to be dominated by the acid/base character of the cations. A linear relationship was found between the enthalpies of formation of the ternaries from binary nitrides and the ionic potential ratio of the two cations. 43 refs., 4 tabs.

  7. Influence of inelastic collisions with hydrogen atoms on the non-LTE modelling of Ca i and Ca ii lines in late-type stars

    Science.gov (United States)

    Mashonkina, L.; Sitnova, T.; Belyaev, A. K.

    2017-09-01

    We performed the non-local thermodynamic equilibrium (non-LTE, NLTE) calculations for Ca i-ii with the updated model atom that includes new quantum-mechanical rate coefficients for Ca i + H i collisions from two recent studies and investigated the accuracy of calcium abundance determinations using the Sun, Procyon, and five metal-poor (MP, -2.6 ≤ [Fe/H] ≤-1.3) stars with well-determined stellar parameters. Including H i collisions substantially reduces over-ionisation of Ca i in the line formation layers compared with the case of pure electronic collisions and thus the NLTE effects on abundances derived from Ca i lines. We show that both collisional recipes lead to very similar NLTE results. As for Ca ii, the classical Drawinian rates scaled by SH = 0.1 are still applied. When using the subordinate lines of Ca i and the high-excitation lines of Ca ii, NLTE provides the smaller line-to-line scatter compared with the LTE case for each star. For Procyon, NLTE removes a steep trend with line strength among strong Ca i lines seen in LTE and leads to consistent [Ca/H] abundances from the two ionisation stages. In the MP stars, the NLTE abundance from Ca ii 8498 Å agrees well with the abundance from the Ca i subordinate lines, in contrast to LTE, where the abundance difference grows towards lower metallicity and reaches 0.46 dex in BD -13°3442 ([Fe/H] = -2.62). NLTE largely removes abundance discrepancies between the high-excitation lines of Ca ii and Ca ii 8498 Å obtained for our four [Fe/H] situation is improved when the calcium abundance decreases and the Ca i 4226 Å line formation depths are shifted into deep atmospheric layers that are dominated by over-ionisation of Ca i. However, the departures from LTE are still underestimated for Ca i 4226 Å at [Ca/H] ≃ -4.4 (HE 0557-4840). Consistent NLTE abundances from the Ca i resonance line and the Ca ii lines are found for HE 0107-5240 and HE 1327-2326 with [Ca/H] ≤-5. Thus, the Ca i/Ca ii ionisation

  8. Frequency dependence of CA3 spike phase response arising from h-current properties

    Directory of Open Access Journals (Sweden)

    Melodie eBorel

    2013-12-01

    Full Text Available The phase of firing of hippocampal neurons during theta oscillations encodes spatial information. Moreover, the spike phase response to synaptic inputs in individual cells depends on the expression of the hyperpolarisation-activated mixed cation current (Ih, which differs between CA3 and CA1 pyramidal neurons. Here, we compared the phase response of these two cell types, as well as their intrinsic membrane properties. We found that both CA3 and CA1 pyramidal neurons show a voltage sag in response to negative current steps but that this voltage sag is significantly smaller in CA3 cells. Moreover, CA3 pyramidal neurons have less prominent resonance properties compared to CA1 pyramidal neurons. This is consistent with differential expression of Ih by the two cell types. Despite their distinct intrinsic membrane properties, both CA3 and CA1 pyramidal neurons displayed bidirectional spike phase control by excitatory conductance inputs during theta oscillations. In particular, excitatory inputs delivered at the descending phase of a dynamic clamp-induced membrane potential oscillation delayed the subsequent spike by nearly 50 mrad. The effect was shown to be mediated by Ih and was counteracted by increasing inhibitory conductance driving the membrane potential oscillation. Using our experimental data to feed a computational model, we showed that differences in Ih between CA3 and CA1 pyramidal neurons could predict frequency-dependent differences in phase response properties between these cell types. We confirmed experimentally such frequency-dependent spike phase control in CA3 neurons. Therefore, a decrease in theta frequency, which is observed in intact animals during novelty, might switch the CA3 spike phase response from unidirectional to bidirectional and thereby promote encoding of the new context.

  9. Synthesis and characterization of CaO-loaded electrospun matrices for bone tissue engineering.

    Science.gov (United States)

    Münchow, Eliseu A; Pankajakshan, Divya; Albuquerque, Maria T P; Kamocki, Krzysztof; Piva, Evandro; Gregory, Richard L; Bottino, Marco C

    2016-11-01

    This study aims to synthesize and characterize biodegradable polymer-based matrices loaded with CaO nanoparticles for osteomyelitis treatment and bone tissue engineering. Poly(ε-caprolactone) (PCL) and PCL/gelatin (1:1, w/w) solutions containing CaO nanoparticles were electrospun into fibrous matrices. Scanning (SEM) and transmission (TEM) electron microscopy, Fourier transformed infrared (FTIR), energy dispersive X-ray spectroscopy (EDS), contact angle (CA), tensile testing, and antibacterial activity (agar diffusion assay) against Staphylococcus aureus were performed. Osteoprecursor cell (MC3T3-E1) response (i.e., viability and alkaline phosphatase expression/ALP) and infiltration into the matrices were evaluated. CaO nanoparticles were successfully incorporated into the fibers, with the median fiber diameter decreasing after CaO incorporation. The CA decreased with the addition of CaO, and the presence of gelatin made the matrix very hydrophilic (CA = 0°). Increasing CaO concentrations progressively reduced the mechanical properties (p ≤ 0.030). CaO-loaded matrices did not display consistent antibacterial activity. MC3T3-E1 cell viability demonstrated the highest levels for CaO-loaded matrices containing gelatin after 7 days in culture. An increased ALP expression was consistently seen for PCL/CaO matrices when compared to PCL and gelatin-containing counterparts. Despite inconsistent antibacterial activity, CaO nanoparticles can be effectively loaded into PCL or PCL/gelatin fibers without negatively affecting the overall performance of the matrices. More importantly, CaO incorporation enhanced cell viability as well as differentiation capacity, as demonstrated by an increased ALP expression. CaO-loaded electrospun matrices show potential for applications in bone tissue engineering.

  10. CaII Κ Imaging to Understand UV Irradiance Variability

    Indian Academy of Sciences (India)

    R. Kariyappa

    2000-09-01

    To identify and understand the underlying physical mechanisms of total solar and UV irradiance variability and to estimate the contribution of various chromospheric features to UV irradiance, detailed analysis of spatially resolved data is required. The various chromospheric features have been segregated and different parameters have been derived from CaII Κ Spectroheliograms of NSO/Sac Peak and Kodaikanal Observatory and compared with UV irradiance flux measured in MgII h and k lines by NOAA 9 satellite. The important results of this detailed analysis of CaII Κ Images of 1992 together with UV irradiance data will be discussed in this paper.

  11. 46 CFR 7.130 - Point Conception, CA to Point Sur, CA.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Point Conception, CA to Point Sur, CA. 7.130 Section 7.130 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Pacific Coast § 7.130 Point Conception, CA to Point Sur, CA. (a) A line drawn from...

  12. Comparing East and West

    DEFF Research Database (Denmark)

    Razeto, Anna

    2014-01-01

    This chapter explores the archaeological and literary evidence for marketplaces and urban forms connected to the manufacturing of bricks and metalworking in the capital cities of the contemporary empires of Rome and Han China (ca. 200 BC-200 AD). The comparative analysis of the physical aspects...... of these urban structures and the following discussion of the impact of the political, practical, ideological and economic circumstances of the two empires on the distribution and features of the architecture and industries presented, will highlight the extent to which the urban architecture of the capitals...

  13. Altered thalamocortical rhythmicity and connectivity in mice lacking CaV3.1 T-type Ca2+ channels in unconsciousness.

    Science.gov (United States)

    Choi, Soonwook; Yu, Eunah; Lee, Seongwon; Llinás, Rodolfo R

    2015-06-23

    In unconscious status (e.g., deep sleep and anesthetic unconsciousness) where cognitive functions are not generated there is still a significant level of brain activity present. Indeed, the electrophysiology of the unconscious brain is characterized by well-defined thalamocortical rhythmicity. Here we address the ionic basis for such thalamocortical rhythms during unconsciousness. In particular, we address the role of CaV3.1 T-type Ca(2+) channels, which are richly expressed in thalamic neurons. Toward this aim, we examined the electrophysiological and behavioral phenotypes of mice lacking CaV3.1 channels (CaV3.1 knockout) during unconsciousness induced by ketamine or ethanol administration. Our findings indicate that CaV3.1 KO mice displayed attenuated low-frequency oscillations in thalamocortical loops, especially in the 1- to 4-Hz delta band, compared with control mice (CaV3.1 WT). Intriguingly, we also found that CaV3.1 KO mice exhibited augmented high-frequency oscillations during unconsciousness. In a behavioral measure of unconsciousness dynamics, CaV3.1 KO mice took longer to fall into the unconscious state than controls. In addition, such unconscious events had a shorter duration than those of control mice. The thalamocortical interaction level between mediodorsal thalamus and frontal cortex in CaV3.1 KO mice was significantly lower, especially for delta band oscillations, compared with that of CaV3.1 WT mice, during unconsciousness. These results suggest that the CaV3.1 channel is required for the generation of a given set of thalamocortical rhythms during unconsciousness. Further, that thalamocortical resonant neuronal activity supported by this channel is important for the control of vigilance states.

  14. Testing coral paleothermometers (B/Ca, Mg/Ca, Sr/Ca, U/Ca andδ18O) under impacts of large riverine runoff

    Institute of Scientific and Technical Information of China (English)

    CHEN Tianran; YU Kefu; ZHAO Jianxin; YAN Hongqiang; SONG Yinxian; FENG Yuexing; CHEN Tegu

    2015-01-01

    Sea surface temperature (SST) proxies including B/Ca, Mg/Ca, Sr/Ca, U/Ca andδ18O were analyzed in the skeleton of aPorites coral collected from the Zhujiang River (Pearl River) Estuary (ZRE). These geochemical proxies are influenced by river runoff and this area of the northern South China Sea is strongly affected by seasonal freshwater floods. We assessed the robustness of each SST proxy through comparison with the local instrumental SST. Coral Sr/Ca shows the highest correlation with SST variations (r2=0.59), suggesting Sr/Ca is the most robust SST proxy. In contrast, coralδ18O (r2=0.46), B/Ca (r2=0.43) and U/Ca (r2=0.41) ratios were only moderately correlated with SST variations, suggesting that they are disturbed by some other factors in addition to SST. The poor correlation (r2=0.27) between SST and Mg/Ca indicates that Mg/Ca in coral skeletons is not a simple function of SST variations. This may ultimately limit the use of Mg/Ca as a coral paleothermometer.

  15. Atrial myocyte function and Ca2+ handling is associated with inborn aerobic capacity.

    Directory of Open Access Journals (Sweden)

    Anne Berit Johnsen

    Full Text Available Although high aerobic capacity is associated with effective cardiac function, the effect of aerobic capacity on atrial function, especially in terms of cellular mechanisms, is not known. We aimed to investigate whether rats with low inborn maximal oxygen uptake (VO2 max had impaired atrial myocyte contractile function when compared to rats with high inborn VO2 max.Atrial myocyte function was depressed in Low Capacity Runners (LCR relative to High Capacity Runners (HCR which was associated with impaired Ca(2+ handling. Fractional shortening was 52% lower at 2 Hz and 60% lower at 5 Hz stimulation while time to 50% relengthening was 43% prolonged and 55% prolonged, respectively. Differences in Ca(2+ amplitude and diastolic Ca(2+ level were observed at 5 Hz stimulation where Ca(2+ amplitude was 70% lower and diastolic Ca(2+ level was 11% higher in LCR rats. Prolonged time to 50% Ca(2+ decay was associated with reduced sarcoplasmic reticulum (SR Ca(2+ ATPase function in LCR (39%. Na(+/Ca(2+ exchanger activity was comparable between the groups. Diastolic SR Ca(2+ leak was increased by 109%. This could be partly explained by increased ryanodine receptors phosphorylation at the Ca(2+-calmodulin-dependent protein kinase-II specific Ser-2814 site in LCR rats. T-tubules were present in 68% of HCR cells whereas only 33% LCR cells had these structures. In HCR, the significantly higher numbers of cells with T-tubules were combined with greater numbers of myocytes where Ca(2+ release in the cell occurred simultaneously in central and peripheral regions, giving rise to faster and more spatial homogenous Ca(2+-signal onset.This data demonstrates that contrasting for low or high aerobic capacity leads to diverse functional and structural remodelling of atrial myocytes, with impaired contractile function in LCR compared to HCR rats.

  16. Multiple Ca2+ sensors in secretion

    DEFF Research Database (Denmark)

    Walter, Alexander M; Groffen, Alexander J; Sørensen, Jakob Balslev;

    2011-01-01

    Regulated neurotransmitter secretion depends on Ca(2+) sensors, C2 domain proteins that associate with phospholipids and soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE) complexes to trigger release upon Ca(2+) binding. Ca(2+) sensors are thought to prevent spontaneous...... fusion at rest (clamping) and to promote fusion upon Ca(2+) activation. At least eight, often coexpressed, Ca(2+) sensors have been identified in mammals. Accumulating evidence suggests that multiple Ca(2+) sensors interact, rather than work autonomously, to produce the complex secretory response...... observed in neurons and secretory cells. In this review, we present several working models to describe how different sensors might be arranged to mediate synchronous, asynchronous and spontaneous neurotransmitter release. We discuss the scenario that different Ca(2+) sensors typically act on one shared...

  17. NMR determination of the Sternheimer antishielding factor of Ca2+.

    Science.gov (United States)

    Trokiner, A; Bellot, P V; Zhdanov, Y; Yakubovskii, A

    2000-06-01

    The experimental determination of the Sternheimer antishielding factor gamma(infinity) for Ca2+ in a sold material is reported for the first time. The gamma(infinity) value was obtained by comparing the quadrupole frequency measured by 43Ca NMR with the electric field gradient calculated in a frame of the point charge approximation in the high-Tc superconducting compound, Tl0.5Pb0.5Sr2CaCu2O7. The deduced value (gamma(infinity)= -6.1+/-.9) is about one-third of that obtained from the quantum mechanical calculations, whereas in the same sample, the gamma(infinity)value for O2- deduced by the same procedure (gamma(infinity)= -13.7+/-2.0) is very close to the calculated one.

  18. Absolute activity determination of CaWO{sub 4} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Muenster, Andrea; Ertl, Andreas; Guetlein, Achim; Lanfranchi, Jean-Come; Potzel, Walter; Roth, Sabine; Simon, Daniel; Scholl, Stephan; Sivers, Moritz von; Strauss, Raimund; Wawoczny, Stephan; Willers, Michael; Wuestrich, Marc; Zoeller, Andreas [TU Muenchen, Fakultaet fuer Physik, E15, Garching (Germany)

    2013-07-01

    The direct Dark Matter search experiment CRESST uses CaWO{sub 4} single crystals as targets for possible WIMP recoils. A particle interaction in the crystal produces phonons as well as scintillation light. As the light signal is dependent on the kind of interacting particle, a particle discrimination on an event-by-event basis is feasible. The observed background is mainly due to intrinsic radioactive impurities of the CaWO{sub 4} target. An activity of this intrinsic contamination can be determined with the investigation of α-decays in the crystal. Up to now, CaWO{sub 4} crystals were produced by suppliers in Russia and Ukraine. Since 2011 we are able to grow CaWO{sub 4} crystals in a Czochralski furnace installed in the crystal laboratory of TU Munich, which has the advantage to better meet the requirements of CRESST and to ensure the availability of CaWO{sub 4} crystals for the successive future multi-material experiment EURECA. To check the radiopurity, first self-grown crystals were investigated in test measurements. In this talk we will present the results for absolute α-activities of self-grown crystals and compare them to α-activities of the crystals installed in the last CRESST run (Run32).

  19. Dephosphorization Thermodynamics of Crude Steel Using CaO-Based Flux

    Institute of Scientific and Technical Information of China (English)

    YANG Yin-dong; McKague A R; McLean A; Sommerville I D

    2003-01-01

    The experiments were carried out at 1 175-1 450 ℃ to study the phosphorus distribution ratio between molten CaO-based slags and carbon saturated hot metal. The phosphate capacity of the slags and the activity coefficient of PO2.5 were calculated from the phosphorus distribution ratio. The effect of addition of CaF2 and/or CaCl2 on the thermodynamic properties of slags was discussed. The correlation of optical basicity with phosphate capacity of slags was studied, and the dephosphorization ability of CaO-based fluxes with various additives was compared with the results from different studies.

  20. SURFACE MODIFICATION OF CaCO3 WITH DENDRITIC CARBOXYLIC ACIDS

    Institute of Scientific and Technical Information of China (English)

    Zhao-xia Guo; Jian Yu

    2002-01-01

    Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at the focal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO3 and the dendritic modifier was proven by IR and mass spectroscopy of the modified CaCO3 after thorough extraction with dichloromethane. The amount of tightly bonded organic modifier was estimated by TGA. It was shown that the amount of bonded molecules decreased with increasing generation number due to the larger number of branches. Compared to unmodified CaCO3, the modified CaCO3 possess different dispersibility in water and in organic solvents.

  1. Connexins and M3 Muscarinic Receptors Contribute to Heterogeneous Ca2+ Signaling in Mouse Aortic Endothelium

    Directory of Open Access Journals (Sweden)

    François-Xavier Boittin

    2013-02-01

    Full Text Available Background/Aims: Smooth muscle tone is controlled by Ca2+ signaling in the endothelial layer. Mouse endothelial cells are interconnected by gap junctions made of Connexin40 (Cx40 and Cx37, which allow the exchange of signaling molecules to coordinate their activity. Here, we investigated the role of Cx40 in the endothelial Ca2+ signaling of the mouse aorta. Methods: Ca2+ imaging was performed on intact aortic endothelium from both wild type (Cx40+/+ and Connexin40-deficient (Cx40 -/- mice. Results: Acetylcholine (ACh induced early fast and high amplitude Ca2+ transients in a fraction of endothelial cells expressing the M3 muscarinic receptors. Inhibition of intercellular communication using carbenoxolone or octanol fully blocked the propagation of ACh-induced Ca2+ transients toward adjacent cells in WT and Cx40-/- mice. As compared to WT, Cx40-/- mice displayed a reduced propagation of ACh-induced Ca2+ waves, indicating that Cx40 contributes to the spreading of Ca2+ signals. The propagation of those Ca2+ responses was not blocked by suramin, a blocker of purinergic ATP receptors, indicating that there is no paracrine effect of ATP release on the Ca2+ waves. Conclusions: Altogether our data show that Cx40 and Cx37 contribute to the propagation and amplification of the Ca2+ signaling triggered by ACh in endothelial cells expressing the M3 muscarinic receptors.

  2. Xenopus tropicalis oocytes as an advantageous model system for the study of intracellular Ca(2+) signalling.

    Science.gov (United States)

    Marchant, J S; Parker, I

    2001-04-01

    1. The purpose of this study was to compare oocytes from the pipid frogs Xenopus tropicalis and Xenopus laevis, with respect to their utility for studying Ca(2+) signalling mechanisms and for expression of heterologous proteins. 2. We show that X. tropicalis oocytes possess an intracellular Ca(2+) store that is mobilized by inositol (1,4,5) trisphosphate (IP(3)). Ca(2+) signalling is activated by endogenous lysophosphatidic acid receptors and cytosolic Ca(2+) activates a plasma membrane chloride conductance. The spatiotemporal organization of cytosolic Ca(2+) signals, from the microscopic architecture of elementary Ca(2+) 'puffs' to the macroscopic patterns of Ca(2+) spiking are closely similar to the local and global patterns of Ca(2+) release previously characterized in oocytes from X. laevis. 3. By injecting X. tropicalis oocytes with cDNA encoding an ER-targeted fluorescent protein construct, we demonstrate the capacity of the X. tropicalis oocyte to readily express heterologous proteins. The organization of ER is polarized across the oocyte, with the IP(3)-releaseable store targeted within an approximately 8 microm wide band that circumscribes the cell. 4. We conclude that the X. tropicalis oocyte shares many of the characteristics that have made oocytes of X. laevis a favoured system for studying Ca(2+) signalling mechanisms. Moreover, X. tropicalis oocytes display further practical advantages in terms of imaging depth, Ca(2+) signal magnitude and electrical properties. These further enhance the appeal of X. tropicalis as an experimental system, in addition to its greater amenability to transgenic approaches.

  3. Cytosolic Ca2+ shifts as early markers of cytotoxicity

    Science.gov (United States)

    2013-01-01

    The determination of the cytotoxic potential of new and so far unknown compounds as well as their metabolites is fundamental in risk assessment. A variety of strategic endpoints have been defined to describe toxin-cell interactions, leading to prediction of cell fate. They involve measurement of metabolic endpoints, bio-energetic parameters or morphological cell modifications. Here, we evaluated alterations of the free cytosolic Ca2+ homeostasis using the Fluo-4 dye and compared results with the metabolic cell viability assay Alamar Blue. We investigated a panel of toxins (As2O3, gossypol, H2O2, staurosporine, and titanium(IV)-salane complexes) in four different mammalian cell lines covering three different species (human, mouse, and African green monkey). All tested compounds induced an increase in free cytosolic Ca2+ within the first 5 s after toxin application. Cytosolic Ca2+ shifts occurred independently of the chemical structure in all tested cell systems and were persistent up to 3 h. The linear increase of free cytosolic Ca2+ within the first 5 s of drug treatment correlates with the EC25 and EC75 values obtained in Alamar Blue assays one day after toxin exposure. Moreover, a rise of cytosolic Ca2+ was detectable independent of induced cell death mode as assessed by caspase and poly(ADP-ribose) polymerase (PARP) activity in HeLa versus MCF-7 cells at very low concentrations. In conclusion, a cytotoxicity assay based on Ca2+ shifts has a low limit of detection (LOD), is less time consuming (at least 24 times faster) compared to the cell viability assay Alamar Blue and is suitable for high-troughput-screening (HTS). PMID:23384168

  4. Short Chosen-Prefix Collisions for MD5 and the Creation of a Rogue CA Certificate

    NARCIS (Netherlands)

    Stevens, M.M.J.; Sotirov, A.; Appelbaum, J.; Lenstra, A.K.; Molnar, D.; Osvik, D.A.; Weger, B. de

    2009-01-01

    We present a refined chosen-prefix collision construction for MD5 that allowed creation of a rogue Certification Authority (CA) certificate, based on a collision with a regular end-user website certificate provided by a commercial CA. Compared to the previous construction from Eurocrypt 2007, this p

  5. Co-60 and Ca-45 autoradiography in cerebral ischemia in the rat

    NARCIS (Netherlands)

    Stevens, H; Krop-van Gastel, W; Korf, J

    1998-01-01

    Radioisotopes of divalent Co (Co-57 in Single photon emission tomography (SPECT)and Co-55 in positron emission tomography (PET) have clinically been applied to visualize Ca related brain damage. The cerebral uptake of Ca-45 and Co-60 in a unilateral stroke model in the rat was compared; 100 mu Ci (C

  6. Structure of molten CaSiO3: neutron diffraction isotope substitution with aerodynamic levitation and molecular dynamics study.

    Science.gov (United States)

    Skinner, L B; Benmore, C J; Weber, J K R; Tumber, S; Lazareva, L; Neuefeind, J; Santodonato, L; Du, J; Parise, J B

    2012-11-15

    We have performed neutron diffraction isotopic substitution experiments on aerodynamically levitated droplets of CaSiO(3), to directly extract intermediate and local structural information on the Ca environment. The results show a substantial broadening of the first Ca-O peak in the pair distribution function of the melt compared to the glass, which comprises primarily of 6- and 7-fold coordinated Ca-polyhedra. The broadening can be explained by a redistribution of Ca-O bond lengths, especially toward longer distances in the liquid. The first order neutron difference function provides a test of recent molecular dynamics simulations and supports the MD model which contains short chains or channels of edge shared Ca-octahedra in the liquid state. It is suggested that the polymerization of Ca-polyhedra is responsible for the fragile viscosity behavior of the melt and the glass forming ability in CaSiO(3).

  7. The structure of molten CaSiO3: A neutron diffraction isotope substitution and aerodynamic levitation study.

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Lawrie [State University of New York, Stony Brook; Benmore, Chris J [Argonne National Laboratory (ANL); Weber, Richard [Argonne National Laboratory (ANL); Santodonato, Louis J [ORNL; Tumber, Sonia [Materials Development, Inc., Evanston, IL; Neuefeind, Joerg C [ORNL; Lazareva, Lena [State University of New York, Stony Brook; Du, Jincheng [University of North Texas; Parise, John B [Stony Brook University (SUNY)

    2012-01-01

    We have performed neutron diffraction isotopic substitution experiments on aerodynamically levitated droplets of CaSiO3, to directly extract intermediate and local structural information on the Ca environment. The results show a substantial broadening of the Ca-O peak in the pair distribution function of the melt compared to the glass, which comprises primarily of 6- and 7-fold coordinated Ca-polyhedra. The broadening can be explained by a re-distribution of Ca-O bond lengths, especially towards longer distances in the liquid. The first order neutron difference function provides a rigorous test of recent molecular dynamics simulations and supports the model of the presence of short chains or channels of edge shared Ca-octahedra in the liquid state. It is suggested that the polymerization of Ca-polyhedra is responsible for the fragile viscosity behavior of the melt and the glass forming ability in CaSiO3.

  8. Effects of antibiotics on the contractility and Ca2+ transients of rat cardiac myocytes.

    Science.gov (United States)

    Belus, A; White, E

    2001-01-26

    We have compared the effects of streptomycin sulphate, gentamicin sulphate and neomycin sulphate on cell shortening (our index of contractility) and intracellular Ca2+ ([Ca2+](i)) transients of rat ventricular myocytes. All three agents abolished shortening and [Ca2+](i), transients but streptomycin was significantly less potent than the other agents. The IC(50) of streptomycin was 0.37 mM for shortening and 0.78 mM for [Ca2+](i), approximately an order of magnitude greater than equivalent values for gentamicin and neomycin. Gentamicin and streptomycin shortened the action potential duration of most cells but prolonged the action potential duration of others. We therefore conclude that multiple ionic mechanisms affecting action potential duration are modulated by these antibiotics. Our observations are consistent with the negative inotropic effect of antibiotics being caused by a decrease in Ca2+ influx causing a reduction in the [Ca2+](i) transient.

  9. A new form of Ca3P2 with a ring of Dirac nodes

    Directory of Open Access Journals (Sweden)

    Lilia S. Xie

    2015-08-01

    Full Text Available We report the synthesis and crystal structure of a new high-temperature form of Ca3P2. The crystal structure was determined through Rietveld refinements of synchrotron powder x-ray diffraction data. This form of Ca3P2 has a crystal structure of the hexagonal Mn5Si3 type, with a Ca ion deficiency compared to the ideal 5:3 stoichiometry. This yields a stable, charge-balanced compound of Ca2+ and P3−. We also report the observation of a secondary hydride phase, Ca5P3H, which again is a charge-balanced compound. The calculated band structure of Ca3P2 indicates that it is a three-dimensional Dirac semimetal with a highly unusual ring of Dirac nodes at the Fermi level. The Dirac states are protected against gap opening by a mirror plane in a manner analogous to what is seen for graphene.

  10. The Role of Mitochondria in the Activation/Maintenance of SOCE: Store-Operated Ca(2+) Entry and Mitochondria.

    Science.gov (United States)

    Spät, András; Szanda, Gergö

    2017-01-01

    Mitochondria extensively modify virtually all cellular Ca(2+) transport processes, and store-operated Ca(2+) entry (SOCE) is no exception to this rule. The interaction between SOCE and mitochondria is complex and reciprocal, substantially altering and, ultimately, fine-tuning both capacitative Ca(2+) influx and mitochondrial function. Mitochondria, owing to their considerable Ca(2+) accumulation ability, extensively buffer the cytosolic Ca(2+) in their vicinity. In turn, the accumulated ion is released back into the neighboring cytosol during net Ca(2+) efflux. Since store depletion itself and the successive SOCE are both Ca(2+)-regulated phenomena, mitochondrial Ca(2+) handling may have wide-ranging effects on capacitative Ca(2+) influx at any given time. In addition, mitochondria may also produce or consume soluble factors known to affect store-operated channels. On the other hand, Ca(2+) entering the cell during SOCE is sensed by mitochondria, and the ensuing mitochondrial Ca(2+) uptake boosts mitochondrial energy metabolism and, if Ca(2+) overload occurs, may even lead to apoptosis or cell death. In several cell types, mitochondria seem to be sterically excluded from the confined space that forms between the plasma membrane (PM) and endoplasmic reticulum (ER) during SOCE. This implies that high-Ca(2+) microdomains comparable to those observed between the ER and mitochondria do not form here. In the following chapter, the above aspects of the many-sided SOCE-mitochondrion interplay will be discussed in greater detail.

  11. In Situ Ca2+ Titration in the Fluorometric Study of Intracellular Ca2+ Binding

    Science.gov (United States)

    McMahon, Shane M.; Jackson, Meyer B.

    2014-01-01

    Imaging with Ca2+-sensitive fluorescent dye has provided a wealth of insight into the dynamics of cellular Ca2+ signaling. The spatiotemporal evolution of intracellular free Ca2+ observed in imaging experiments is shaped by binding and unbinding to cytoplasmic Ca2+ buffers, as well as the fluorescent indicator used for imaging. These factors must be taken into account in the interpretation of Ca2+ imaging data, and can be exploited to investigate endogenous Ca2+ buffer properties. Here we extended the use of Ca2+ fluorometry in the characterization of Ca2+ binding molecules within cells, building on a method of titration of intracellular Ca2+ binding sites in situ with measured amounts of Ca2+ entering through voltage-gated Ca2+ channels. We developed a systematic procedure for fitting fluorescence data acquired during a series of voltage steps to models with multiple Ca2+ binding sites. The method was tested on simulated data, and then applied to 2-photon fluorescence imaging data from rat posterior pituitary nerve terminals patch clamp-loaded with the Ca2+ indicator fluo-8. Focusing on data sets well described by a single endogenous Ca2+ buffer and dye, this method yielded estimates of the endogenous buffer concentration and Kd, the dye Kd, and the fraction of Ca2+ inaccessible cellular volume. The in situ Kd of fluo-8 thus obtained was indistinguishable from that measured in vitro. This method of calibrating Ca2+-sensitive fluorescent dyes in situ has significant advantages over previous methods. Our analysis of Ca2+ titration fluorometric data makes more effective use of the experimental data, and provides a rigorous treatment of multivariate errors and multiple Ca2+ binding species. This method offers a versatile approach to the study of endogenous Ca2+ binding molecules in their physiological milieu. PMID:25465896

  12. Hospital Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Compare has information about the quality of care at over 4,000 Medicare-certified hospitals across the country. You can use Hospital Compare to find...

  13. Inhibition of CaMKII does not attenuate cardiac hypertrophy in mice with dysfunctional ryanodine receptor.

    Directory of Open Access Journals (Sweden)

    Asima Chakraborty

    Full Text Available In cardiac muscle, the release of calcium ions from the sarcoplasmic reticulum through ryanodine receptor ion channels (RyR2s leads to muscle contraction. RyR2 is negatively regulated by calmodulin (CaM and by phosphorylation of Ca2+/CaM-dependent protein kinase II (CaMKII. Substitution of three amino acid residues in the CaM binding domain of RyR2 (RyR2-W3587A/L3591D/F3603A, RyR2ADA impairs inhibition of RyR2 by CaM and results in cardiac hypertrophy and early death of mice carrying the RyR2ADA mutation. To test the cellular function of CaMKII in cardiac hypertrophy, mutant mice were crossed with mice expressing the CaMKII inhibitory AC3-I peptide or the control AC3-C peptide in the myocardium. Inhibition of CaMKII by AC3-I modestly reduced CaMKII-dependent phosphorylation of RyR2 at Ser-2815 and markedly reduced CaMKII-dependent phosphorylation of SERCA2a regulatory subunit phospholamban at Thr-17. However the average life span and heart-to-body weight ratio of Ryr2ADA/ADA mice expressing the inhibitory peptide were not altered compared to control mice. In Ryr2ADA/ADA homozygous mice, AC3-I did not alter cardiac morphology, enhance cardiac function, improve sarcoplasmic reticulum Ca2+ handling, or suppress the expression of genes implicated in cardiac remodeling. The results suggest that CaMKII was not required for the rapid development of cardiac hypertrophy in Ryr2ADA/ADA mice.

  14. cgpCaVEManWrapper: Simple Execution of CaVEMan in Order to Detect Somatic Single Nucleotide Variants in NGS Data.

    Science.gov (United States)

    Jones, David; Raine, Keiran M; Davies, Helen; Tarpey, Patrick S; Butler, Adam P; Teague, Jon W; Nik-Zainal, Serena; Campbell, Peter J

    2016-12-08

    CaVEMan is an expectation maximization-based somatic substitution-detection algorithm that is written in C. The algorithm analyzes sequence data from a test sample, such as a tumor relative to a reference normal sample from the same patient and the reference genome. It performs a comparative analysis of the tumor and normal sample to derive a probabilistic estimate for putative somatic substitutions. When combined with a set of validated post-hoc filters, CaVEMan generates a set of somatic substitution calls with high recall and positive predictive value. Here we provide instructions for using a wrapper script called cgpCaVEManWrapper, which runs the CaVEMan algorithm and additional downstream post-hoc filters. We describe both a simple one-shot run of cgpCaVEManWrapper and a more in-depth implementation suited to large-scale compute farms. © 2016 by John Wiley & Sons, Inc.

  15. Thermodynamics of calmodulin trapping by Ca2+/calmodulin-dependent protein kinase II: subpicomolar Kd determined using competition titration calorimetry.

    Science.gov (United States)

    Tse, Joyce K Y; Giannetti, Anthony M; Bradshaw, J Michael

    2007-04-03

    Calmodulin (CaM) trapping by Ca2+/calmodulin-dependent protein kinase II (CaMKII) is a phenomenon whereby the affinity of CaM for CaMKII increases >1000-fold following CaMKII autophosphorylation. The molecular basis of this effect is not entirely understood. Binding of CaM to the phosphorylated and the unphosphorylated states of CaMKII is well mimicked by the interaction of CaM with two different length peptides taken from the CaM-binding region of CaMKII, peptides we refer to as the long and intermediate peptides. To better understand the conformational change accompanying CaM trapping, we have used isothermal titration calorimetry (ITC) to compare the binding thermodynamics of CaM to these peptides as well as to a shorter CaMKII-based peptide. Calorimetric analysis revealed that the enthalpy, rather than the entropy, distinguished binding of these three peptides. Furthermore, the heat capacity change was found to be similar for the long and intermediate peptides but smaller in magnitude for the short peptide. Direct titration of CaM with peptide provided the Kd value for the short peptide (Kd = 5.9 +/- 2.4 microM), but a novel, two-phased competitive binding strategy was necessary to ascertain the affinities of the intermediate (Kd = 0.17 +/- 0.06 nM) and long (Kd = 0.07 +/- 0.04 pM) peptides. To our knowledge, the Kd for the long peptide is the most potent measured to date using ITC. Together, the findings reported here support a model whereby the final conformational change accompanying CaM trapping buries little additional surface area but does involve formation of new hydrogen bonds and van der Waals contacts that contribute to formation of the high-affinity, CaM-trapped state.

  16. Calcium carbene complexes with boranophosphorano side-arms: CaC[P(Ph)(2)BH(3)](2).

    Science.gov (United States)

    Orzechowski, Lars; Jansen, Georg; Lutz, Martin; Harder, Sjoerd

    2009-04-28

    The ligand H(2)C(PPh(2)BH(3))(2) (-H(2)) reacted with one or a half equivalent of (para-tBu-C(6)H(4)CH(2))(2)Ca.(THF)(4) to form the calcium complexes Ca[HC(PPh(2)BH(3))(2)](2) (-H)(2)Ca and CaC(PPh(2)BH(3))(2) (-Ca), respectively. The crystal structures of their THF adducts (-H)(2)Ca.THF and [-Ca.(THF)](2) follow the same trends as observed for the corresponding iminophosphorano substituted complexes Ca[HC(PPh(2)NR)(2)](2) and [CaC(PPh(2)NR)(2)](2). The P-C bonds shorten upon gradual deprotonation, whereas the P-B and P-N bonds elongate. The geometries of DFT-optimized model systems and complete molecular structures show similar trends. Also the charge distribution within the boranophosphorano complexes is similar to that in the iminophosphorano complexes. The high positive charges on Ca (1.74-1.75) indicate a predominantly ionic ligand-Ca bonding. High negative charges on the central carbon atom (-1.103 in Ca[HC(PH(2)BH(3))(2)](2) and -1.775 in [CaC(PH(2)BH(3))(2)](2)) compare well to those calculated for analogous iminophosphorano complexes (-1.126 Ca[HC(PH(2)NH)(2)](2) and -1.847 [CaC(PH(2)NH)(2)](2), respectively). Thus, in both types of complexes delocalization of electron density over the boranophosphorano or iminophosphorano substituents does not play a major role. Complex [-Ca.(THF)](2) does not react with adamantyl cyanide. Instead the adduct (-Ca)(2).(THF).(adamantyl-C[triple bond, length as m-dash]N) formed (a crystal structure has been determined).

  17. Involvement of Ca2+/CaM in the signal transduction of acetylcholine regulating stomatal movement

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    It has been known that the neurotransmitter acetylcholine (ACh) also exists in plants and is able to regulate the movement of stomata. In another aspect, Ca2+/CaM as the second messengers have a critical role of signal transduction in stomatal guard-cell. Here we showed that Ca2+/CaM were also involved in theACh regulated stomatal movement. In the medium containing Ca2+, the Ca2+ channel blockers (NIF and Ver) and CaM inhibitors (TFP and W7) could neutralize the ACh induced stomatal opening, however, they are ineffective in the medium containing K+. Those results indicated that Ca2+/CaM were involved in the signal transduction pathway of ACh regulating stomatal movement.

  18. Influence of NaCl-CaCl2 on Decomposing REPO4 with CaO

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The influence of NaCl-CaCl2 on thermal decomposition of REPO4 (RE: Ce, La, Nd, Th) with CaO was studied.The heat decomposing process of REPO4 was tested with TG-DTA experiments.The results showed that the decomposition temperature of REPO4 with CaO was reduced because of adding NaCl-CaCl2 mixture (NaCl:CaCl2=1:1).The influence of the addition of NaCl-CaCl2, roasting temperature and roasting time on decomposition ratio of REPO4 with CaO was studied.The results showed that the decomposition ratio of REPO4with CaO was 79% when the addition percentage of NaCl-CaCl2 was 10%, the roasting temperature was 750℃, and the roasting time was 1 h.

  19. On the crystal chemistry of olivine-type germanate compounds, Ca1 + xM1 - xGeO4 (M2+ = Ca, Mg, Co, Mn).

    Science.gov (United States)

    Redhammer, Günther J; Roth, Georg; Amthauer, Georg; Lottermoser, Werner

    2008-06-01

    Germanate compounds, CaMGeO(4) with M(2+) = Ca, Mg, Co and Mn, were synthesized as single crystals by slow cooling from the melt or by flux growth techniques. All the compositions investigated exhibit Pnma symmetry at 298 K and adopt the olivine structure. The M2 site is exclusively occupied by Ca(2+), while on M1 both Ca(2+) and M(2+) cations are found. The amount of Ca(2+) on M1 increases with the size of the M1 cation, with the smallest amount in the Mg compound (0.1 atoms per formula unit) and the largest in the Mn compound (0.20 atoms per formula unit), while in Ca(2)GeO(4), also with olivine structure, both sites are completely filled with Ca(2+). When compared with those of Ca silicate olivine, the lattice parameters a and c are distinctly larger in the analogous germanate compounds, while b has essentially the same values, regardless of the tetrahedral cation, meaning that b is independent of the tetrahedral cation. Structural variations on the octahedrally coordinated M1 site are largely determined by the size of the M1 cation, the average M1-O bond lengths being identical in Ca silicate and Ca germanate olivine. Increasing the size of the M1 cation induces an increasing polyhedral distortion, expressed by the parameters bond-length distortion, octahedral angle variance and octahedral quadratic elongation. However, the Ca germanate olivine compounds generally have more regular octahedra than the analogous silicates. The octahedrally coordinated M2 site does not exhibit large variations in structural parameters as a consequence of the constant chemical composition; the same is valid for the tetrahedral site.

  20. Effect of charge compensator/CO-dopant ions on the TL characteristics of CaSO{sub 4}:Dy and CaSO{sub 4}:Tm

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, B.C.; Shinde, S.S.; Srivastava, J.K. [Bhabha Atomic Research Centre, Bombay (India); Gundu Rao, T.K. [Indian Inst. of Tech., Bombay (India)

    1996-12-31

    The effect of charge compensating ions (Na{sup +} or P{sup 5+}) has been studied in CaSO{sub 4}:Dy/Tm phosphors. For CaSO{sub 4}:Dy, Na, the thermoluminescence emission between 380 and 404 K seems to be well correlated with Na co-dopant which increases the formation and stabilisation of the SO{sub 4}{sup -} centre. ESR as well as fluorescence measurements also showed an enhanced signal for the SO{sub 4}{sup -} radical in CaSO{sub 4}:Dy, Na samples. Co-doping of phosphorus in CaSO{sub 4}:Dy/Tm resulted in increasing the TL sensitivity by about 40% when compared with that in the conventional CaSO{sub 4}:Dy/Tm TL phosphors. In CaSO{sub 4}:Dy,P and CaSO{sub 4}:Dy, while ESR measurements showed no change in ESR signal intensity. TL measurements showed higher intensity for CaSO{sub 4}:Dy,P samples. On the other hand, addition of Zr{sup 4+} to CaSO{sub 4}:Dy did not result in any enhancement in TL intensity of the dosimetric peak; however, ESR measurements showed enhanced intensity for the SO{sub 3}{sup -} radical (stable up to 300{sup o}C) in CaSO{sub 4}:Dy,Zr. These results tend to show that charge compensator ions such as Na{sup +} and P{sup 5+} when present in CaSO{sub 4}:Dy/Tm, result in higher luminescence efficiency either due to better incorporation of activator ions or due to improvement in energy transfer processes. On the other hand incorporation of co-dopant ions with higher effective charge such as Zr{sup 4+} would increase the concentration of cation vacancies but did not result in an increase in the luminescence efficiency. (Author).

  1. Determination of Sr and Ca sources in small tropical catchments (La Selva, Costa Rica) - A comparison of Sr and Ca isotopes

    Science.gov (United States)

    Wiegand, B. A.; Schwendenmann, L.

    2013-04-01

    SummaryA comparative study of Sr and Ca isotopes was conducted to assess solute sources and effects of biogeochemical processes on surface water and groundwater in four small tropical catchments located at La Selva Biological Station, Costa Rica. Variable concentrations of dissolved Sr2+ and Ca2+ in the catchments are related to mixing of waters from different origin. Three catchments are influenced by high-solute bedrock groundwater, while another catchment is primarily supplied by local recharge. 87Sr/86Sr ratios were employed to discriminate contributions from mineral weathering and atmospheric sources. Solutes in bedrock groundwater have a predominant geogenic origin, whereas local recharge is characterized by low-solute inputs from rainwater and minor in situ weathering releases from nutrient-depleted soils. Bedrock groundwater contributes more than 60% of dissolved Sr2+ to surface discharge in the Salto, Saltito, and Arboleda catchments, whereas the Taconazo catchment receives more than 95% of dissolved Sr2+ from rainwater. δ44/40Ca values of dissolved Ca2+ vary greatly in the catchments, mainly as a result of heterogeneous Ca isotope compositions of the contributing sources. Based on differences in δ44/40Ca values, two distinct bedrock groundwaters discharging at the Salto and the Arboleda catchments are suggested. Effects of biological processes in the plant-soil system on solute generation in the catchments are indicated by variable Ca/Sr ratios. However, these effects cannot clearly be assessed by Ca isotopes due to the strong heterogeneity of δ44/40Ca values of Ca2+ sources and high Ca2+ concentrations in bedrock groundwater.

  2. γCaMKII shuttles Ca²⁺/CaM to the nucleus to trigger CREB phosphorylation and gene expression.

    Science.gov (United States)

    Ma, Huan; Groth, Rachel D; Cohen, Samuel M; Emery, John F; Li, Boxing; Hoedt, Esthelle; Zhang, Guoan; Neubert, Thomas A; Tsien, Richard W

    2014-10-09

    Activity-dependent CREB phosphorylation and gene expression are critical for long-term neuronal plasticity. Local signaling at CaV1 channels triggers these events, but how information is relayed onward to the nucleus remains unclear. Here, we report a mechanism that mediates long-distance communication within cells: a shuttle that transports Ca(2+)/calmodulin from the surface membrane to the nucleus. We show that the shuttle protein is γCaMKII, its phosphorylation at Thr287 by βCaMKII protects the Ca(2+)/CaM signal, and CaN triggers its nuclear translocation. Both βCaMKII and CaN act in close proximity to CaV1 channels, supporting their dominance, whereas γCaMKII operates as a carrier, not as a kinase. Upon arrival within the nucleus, Ca(2+)/CaM activates CaMKK and its substrate CaMKIV, the CREB kinase. This mechanism resolves long-standing puzzles about CaM/CaMK-dependent signaling to the nucleus. The significance of the mechanism is emphasized by dysregulation of CaV1, γCaMKII, βCaMKII, and CaN in multiple neuropsychiatric disorders.

  3. Dissection of local Ca(2+) signals inside cytosol by ER-targeted Ca(2+) indicator.

    Science.gov (United States)

    Niwa, Fumihiro; Sakuragi, Shigeo; Kobayashi, Ayana; Takagi, Shin; Oda, Yoichi; Bannai, Hiroko; Mikoshiba, Katsuhiko

    2016-10-07

    Calcium (Ca(2+)) is a versatile intracellular second messenger that operates in various signaling pathways leading to multiple biological outputs. The diversity of spatiotemporal patterns of Ca(2+) signals, generated by the coordination of Ca(2+) influx from the extracellular space and Ca(2+) release from the intracellular Ca(2+) store the endoplasmic reticulum (ER), is considered to underlie the diversity of biological outputs caused by a single signaling molecule. However, such Ca(2+) signaling diversity has not been well described because of technical limitations. Here, we describe a new method to report Ca(2+) signals at subcellular resolution. We report that OER-GCaMP6f, a genetically encoded Ca(2+) indicator (GECI) targeted to the outer ER membrane, can monitor Ca(2+) release from the ER at higher spatiotemporal resolution than conventional GCaMP6f. OER-GCaMP6f was used for in vivo Ca(2+) imaging of C. elegans. We also found that the spontaneous Ca(2+) elevation in cultured astrocytes reported by OER-GCaMP6f showed a distinct spatiotemporal pattern from that monitored by plasma membrane-targeted GCaMP6f (Lck-GCaMP6f); less frequent Ca(2+) signal was detected by OER-GCaMP6f, in spite of the fact that Ca(2+) release from the ER plays important roles in astrocytes. These findings suggest that targeting of GECIs to the ER outer membrane enables sensitive detection of Ca(2+) release from the ER at subcellular resolution, avoiding the diffusion of GECI and Ca(2+). Our results indicate that Ca(2+) imaging with OER-GCaMP6f in combination with Lck-GCaMP6f can contribute to describing the diversity of Ca(2+) signals, by enabling dissection of Ca(2+) signals at subcellular resolution.

  4. Studying CaSO4:Eu as an OSL phosphor

    Science.gov (United States)

    Guckan, Veysi; Altunal, Volkan; Nur, Necmettin; Depci, Tolga; Ozdemir, Adnan; Kurt, Kasim; Yu, Yan; Yegingil, Ihami; Yegingil, Zehra

    2017-09-01

    This study was carried out to investigate the properties of the OSL signal from Eu-doped calcium sulfate (CaSO4:Eu) phosphor and study on its thermal behavior as a function of temperature under a series of luminescence experiments. The suitability of its usage as an optically stimulated luminescence (OSL) dosimeter was also checked. CaSO4:Eu was synthesized using the precipitation method and prepared in pellet form. The dopant concentration value was performed as 0.1 mol%. The synthesized CaSO4:Eu was analyzed by X-ray diffraction (XRD) method to confirm the product. To have an idea about the crystallography and microstructure morphology of the material, scanning electron microscope (SEM) analysis were carried out. It was found that the OSL signal is a resultant signal having three components and exhibits thermal quenching above 150 °C. The excitation spectrum of CaSO4:Eu showed different peaks in the region 220-360 nm with the highest one at 269 nm. Thermoluminescence (TL) signals of CaSO4:Eu pellets were obtained and compared with the TL signals obtained after OSL measurements of the same pellets by blue light stimulation. The low temperature peak near 180 °C did not show any significant change in TL after OSL measurement whereas the high temperature peak at 240 °C was bleached with the blue light illumination and might be responsible for the observed OSL signal. The dosimetric properties such as dose response, minimum detectable dose, energy response, reusability, fading properties, thermal stability and effect of reading temperatures on OSL signals were examined. OSL signals of CaSO4:Eu pellets were decreased by approximately 8% at the end of the 24 h and by about 7% at the end of 28 days when compared with the first readout. The thermal stability of the ∼240 °C TL peak and OSL signal using isothermal decay measurements were used to determine the trap parameters. The CaSO4:Eu OSL dosimeter in accordance with the presented study allows a high

  5. Ca2+ uptake by the endoplasmic reticulum Ca2+-ATPase in rat microvascular endothelial cells.

    Science.gov (United States)

    Moccia, Francesco; Berra-Romani, Roberto; Baruffi, Silvana; Spaggiari, Santina; Signorelli, Silvia; Castelli, Loretta; Magistretti, Jacopo; Taglietti, Vanni; Tanzi, Franco

    2002-01-01

    In non-excitable cells, many agonists increase the intracellular Ca(2+) concentration ([Ca(2+)](i)) by inducing an inositol 1,4,5-trisphosphate (IP(3))-mediated Ca(2+) release from the intracellular stores. Ca(2+) influx from the extracellular medium may then sustain the Ca(2+) signal. [Ca(2+)](i) recovers its resting level as a consequence of Ca(2+)-removing mechanisms, i.e. plasma-membrane Ca(2+)-ATPase (PMCA) pump, Na(+)/Ca(2+) exchanger (NCX) and sarco-endoplasmic reticulum Ca(2+)-ATPase (SERCA) pump. In a study performed in pancreatic acinar cells, evidence has been provided suggesting that, during the decay phase of the agonist-evoked Ca(2+) transients, the Ca(2+) concentration within the intracellular stores remains essentially constant [Mogami, Tepikin and Petersen (1998) EMBO J. 17, 435-442]. It was therefore hypothesized that, in such a situation, intracellular Ca(2+) is not only picked up by the SERCA pump, but is also newly released through IP(3)-sensitive Ca(2+) channels, with the balance between these two processes being approximately null. The main aim of the present work was to test this hypothesis by a different experimental approach. Using cardiac microvascular endothelial cells, we found that inhibition of the SERCA pump has no effect on the time course of agonist-evoked Ca(2+) transients. This result was not due to a low capacity of the SERCA pump since, after agonist removal, this pump proved to be very powerful in clearing the excess of intracellular Ca(2+). We showed further that: (i) in order to avoid a rapid removal of Ca(2+) by the SERCA pump, continuous IP(3) production appears to be required throughout all of the decay phase of the Ca(2+) transient; and (ii) Ca(2+) picked up by the SERCA pump can be fully and immediately released by agonist application. All these results support the model of Mogami, Tepikin and Petersen [(1998) EMBO J. 17, 435-442]. Since the SERCA pump did not appear to be involved in shaping the decay phase of the

  6. Localized Calcineurin Confers Ca2+-Dependent Inactivation Upon Neuronal L-Type Ca2+ Channels

    OpenAIRE

    2012-01-01

    Excitation-driven entry of Ca2+ through L-type voltage-gated Ca2+ channels controls gene expression in neurons and a variety of fundamental activities in other kinds of excitable cells. The probability of opening of CaV1.2 L-type channels is subject to pronounced enhancement by cAMP-dependent protein kinase (PKA), which is scaffolded to CaV1.2 channels by A-kinase anchoring proteins (AKAPs). CaV1.2 channels also undergo negative autoregulation via Ca2+-dependent inactivation (CDI), which stro...

  7. Interlamellar CA1 network in the hippocampus

    OpenAIRE

    Yang, Sunggu; Yang, Sungchil; Moreira, Thais; Hoffman, Gloria; Carlson, Greg C.; Bender, Kevin J.; Alger, Bradley E.; Tang, Cha-Min

    2014-01-01

    It has generally been thought that CA1 cells form only negligible connections with each other along the longitudinal axis of the hippocampus. But if CA1 cells were interconnected in an effective autoassociational network, this information would add a critical new dimension to our understanding of cellular processing within this structure. Here, we report the existence of a well-organized, longitudinally projecting synaptic network among CA1 pyramidal neurons. We further show that synapses of ...

  8. Optimization and application of ICPMS with dynamic reaction cell for precise determination of 44Ca/40Ca isotope ratios.

    Science.gov (United States)

    Boulyga, Sergei F; Klötzli, Urs; Stingeder, Gerhard; Prohaska, Thomas

    2007-10-15

    An inductively coupled plasma mass spectrometer with dynamic reaction cell (ICP-DRC-MS) was optimized for determining (44)Ca/(40)Ca isotope ratios in aqueous solutions with respect to (i) repeatability, (ii) robustness, and (iii) stability. Ammonia as reaction gas allowed both the removal of (40)Ar+ interference on (40)Ca+ and collisional damping of ion density fluctuations of an ion beam extracted from an ICP. The effect of laboratory conditions as well as ICP-DRC-MS parameters such a nebulizer gas flow rate, rf power, lens potential, dwell time, or DRC parameters on precision and mass bias was studied. Precision (calculated using the "unbiased" or "n - 1" method) of a single isotope ratio measurement of a 60 ng g(-1) calcium solution (analysis time of 6 min) is routinely achievable in the range of 0.03-0.05%, which corresponded to the standard error of the mean value (n = 6) of 0.012-0.020%. These experimentally observed RSDs were close to theoretical precision values given by counting statistics. Accuracy of measured isotope ratios was assessed by comparative measurements of the same samples by ICP-DRC-MS and thermal ionization mass spectrometry (TIMS) by using isotope dilution with a (43)Ca-(48)Ca double spike. The analysis time in both cases was 1 h per analysis (10 blocks, each 6 min). The delta(44)Ca values measured by TIMS and ICP-DRC-MS with double-spike calibration in two samples (Ca ICP standard solution and digested NIST 1486 bone meal) coincided within the obtained precision. Although the applied isotope dilution with (43)Ca-(48)Ca double-spike compensates for time-dependent deviations of mass bias and allows achieving accurate results, this approach makes it necessary to measure an additional isotope pair, reducing the overall analysis time per isotope or increasing the total analysis time. Further development of external calibration by using a bracketing method would allow a wider use of ICP-DRC-MS for routine calcium isotopic measurements, but it

  9. High-pressure X-ray diffraction and Raman spectroscopy of CaFe2O4-type β-CaCr2O4

    Science.gov (United States)

    Zhai, Shuangmeng; Yin, Yuan; Shieh, Sean R.; Shan, Shuangming; Xue, Weihong; Wang, Ching-Pao; Yang, Ke; Higo, Yuji

    2016-04-01

    In situ high-pressure synchrotron X-ray diffraction and Raman spectroscopic studies of orthorhombic CaFe2O4-type β-CaCr2O4 chromite were carried out up to 16.2 and 32.0 GPa at room temperature using multi-anvil apparatus and diamond anvil cell, respectively. No phase transition was observed in this study. Fitting a third-order Birch-Murnaghan equation of state to the P-V data yields a zero-pressure volume of V 0 = 286.8(1) Å3, an isothermal bulk modulus of K 0 = 183(5) GPa and the first pressure derivative of isothermal bulk modulus K 0' = 4.1(8). Analyses of axial compressibilities show anisotropic elasticity for β-CaCr2O4 since the a-axis is more compressible than the b- and c-axis. Based on the obtained and previous results, the compressibility of several CaFe2O4-type phases was compared. The high-pressure Raman spectra of β-CaCr2O4 were analyzed to determine the pressure dependences and mode Grüneisen parameters of Raman-active bands. The thermal Grüneisen parameter of β-CaCr2O4 is determined to be 0.93(2), which is smaller than those of CaFe2O4-type CaAl2O4 and MgAl2O4.

  10. MgCaCO3 Versus CaCO3 in Peritoneal Dialysis Patients – A Cross-Over Pilot Trial

    Science.gov (United States)

    Evsanaa, Baigalmaa; Liu, Irene; Aliazardeh, Babak; Mahdavi, Sara; Bajwa, Gursarn; Gula, Jerry; Tam, Michelle; Sze, Elena; Roscoe, Janet M.; Tam, Paul Y.; Sikaneta, Tabo

    2015-01-01

    ♦ Background: Despite adverse effects such as constipation, vascular calcification, and hypercalcemia, calcium-based salts are relatively affordable and effective phosphate binders that remain in widespread use in the dialysis population. We conducted a pilot study examining whether the use of a combined magnesium/calcium-based binder was as effective as calcium carbonate at lowering serum phosphate levels in peritoneal dialysis (PD) patients. ♦ Methods: This was a cross-over, investigator-masked pilot study in which prevalent PD patients received calcium carbonate alone (200 mg calcium per tablet) or calcium magnesium carbonate (100 mg calcium, 85 mg magnesium per tablet). Primary outcome was serum phosphate level at 3 months. Analysis was as per protocol. ♦ Results: Twenty patients were recruited, 17 completed the study. Mean starting dose was 11.35 ± 7.04 pills per day of MgCaCO3 and 9.00 ± 4.97 pills per day of CaCO3. Mean phosphate levels fell from 2.13 mmol/L to 2.01 mmol/L (95% confidence interval (CI): 1.76 – 2.30, p = 0.361) in the MgCaCO3 group, and 1.81 mmol/L (95% CI: 1.56 – 2.0, p = 0.026) in the CaCO3 alone group. Six (35%) patients taking MgCaCO3 and 9 (54%) taking CaCO3 alone achieved Kidney Disease Outcomes Quality Initiative (KDOQI) serum phosphate targets at 3 months. Diarrhea developed in 9 patients taking MgCaCO3 and 3 taking CaCO3. Serum magnesium exceeded 1.4 mmol/L in 5 patients taking MgCaCO3 while serum calcium exceeded 2.65 mmol/L in 3 patients receiving CaCO3. When compared to the initial dose, the prescribed dose at 3 months was reduced by 44% (to 6.41 tablets/day) in the MgCaCO3 group and by 8% (to 8.24 pills per day) in the CaCO3 alone group. ♦ Conclusion: Compared with CaCO3 alone, the preparation and dose of MgCaCO3 used in this pilot study was no better at lowering serum phosphate levels in PD patients, and was associated with more dose-limiting side effects. PMID:24584605

  11. Glutamate excitotoxicity and Ca2+-regulation of respiration: Role of the Ca2+ activated mitochondrial transporters (CaMCs).

    Science.gov (United States)

    Rueda, Carlos B; Llorente-Folch, Irene; Traba, Javier; Amigo, Ignacio; Gonzalez-Sanchez, Paloma; Contreras, Laura; Juaristi, Inés; Martinez-Valero, Paula; Pardo, Beatriz; Del Arco, Araceli; Satrustegui, Jorgina

    2016-08-01

    Glutamate elicits Ca(2+) signals and workloads that regulate neuronal fate both in physiological and pathological circumstances. Oxidative phosphorylation is required in order to respond to the metabolic challenge caused by glutamate. In response to physiological glutamate signals, cytosolic Ca(2+) activates respiration by stimulation of the NADH malate-aspartate shuttle through Ca(2+)-binding to the mitochondrial aspartate/glutamate carrier (Aralar/AGC1/Slc25a12), and by stimulation of adenine nucleotide uptake through Ca(2+) binding to the mitochondrial ATP-Mg/Pi carrier (SCaMC-3/Slc25a23). In addition, after Ca(2+) entry into the matrix through the mitochondrial Ca(2+) uniporter (MCU), it activates mitochondrial dehydrogenases. In response to pathological glutamate stimulation during excitotoxicity, Ca(2+) overload, reactive oxygen species (ROS), mitochondrial dysfunction and delayed Ca(2+) deregulation (DCD) lead to neuronal death. Glutamate-induced respiratory stimulation is rapidly inactivated through a mechanism involving Poly (ADP-ribose) Polymerase-1 (PARP-1) activation, consumption of cytosolic NAD(+), a decrease in matrix ATP and restricted substrate supply. Glutamate-induced Ca(2+)-activation of SCaMC-3 imports adenine nucleotides into mitochondria, counteracting the depletion of matrix ATP and the impaired respiration, while Aralar-dependent lactate metabolism prevents substrate exhaustion. A second mechanism induced by excitotoxic glutamate is permeability transition pore (PTP) opening, which critically depends on ROS production and matrix Ca(2+) entry through the MCU. By increasing matrix content of adenine nucleotides, SCaMC-3 activity protects against glutamate-induced PTP opening and lowers matrix free Ca(2+), resulting in protracted appearance of DCD and protection against excitotoxicity in vitro and in vivo, while the lack of lactate protection during in vivo excitotoxicity explains increased vulnerability to kainite-induced toxicity in Aralar

  12. The initial 41Ca/40Ca ratios in two type A Ca-Al-rich inclusions: Implications for the origin of short-lived 41Ca

    Science.gov (United States)

    Liu, Ming-Chang

    2017-03-01

    This paper reports new 41Ca-41K isotopic data for two Type A CAIs, NWA 3118 #1Nb (Compact Type A) and Vigarano 3138 F8 (Fluffy Type A), from reduced CV3 chondrites. The NWA CAI is found to have carried live 41Ca at the level of (4.6 ± 1.9) ×10-9 , consistent with the proposed Solar System initial 41Ca /40Ca = 4.2 ×10-9 by Liu et al. (2012a). On the other hand, the Vigarano CAI does not have resolvable radiogenic 41K excesses that can be attributed to the decay of 41Ca. Combined with the 26Al data that have been reported for these two CAIs, we infer that the 41Ca distribution was not homogeneous when 26Al was widespread at the canonical level of 26Al /27Al = 5.2 ×10-5 . Such a 41Ca heterogeneity can be understood under two astrophysical contexts: in situ charged particle irradiation by the protoSun in the solar nebula that had inherited some baseline 10Be abundance from the molecular cloud, and Solar System formation in a molecular cloud enriched in 26Al and 41Ca contaminated by massive star winds. That said, more high quality 41Ca data are still needed to better understand the origin of this radionuclide.

  13. Spectrum and Prevalence of CALM1-, CALM2-, and CALM3-Encoded Calmodulin (CaM) Variants in Long QT Syndrome (LQTS) and Functional Characterization of a Novel LQTS-Associated CaM Missense Variant, E141G

    Science.gov (United States)

    Calvert, Melissa L.; Tester, David J.; Kryshtal, Dmytro; Hwang, Hyun Seok; Johnson, Christopher N.; Chazin, Walter J.; Loporcaro, Christina G.; Shah, Maully; Papez, Andrew L.; Lau, Yung R.; Kanter, Ronald; Knollmann, Bjorn C.; Ackerman, Michael J.

    2016-01-01

    Background Calmodulin (CaM) is encoded by three genes, CALM1, CALM2, and CALM3, all of which harbor pathogenic variants linked to long QT syndrome (LQTS) with early and severe expressivity. These LQTS-causative variants reduce CaM affinity to Ca2+ and alter the properties of the cardiac L-type calcium channel (CaV1.2). CaM also modulates NaV1.5 and the ryanodine receptor, RyR2. All of these interactions may play a role in disease pathogenesis. Here, we determine the spectrum and prevalence of pathogenic CaM variants in a cohort of genetically elusive LQTS, and functionally characterize the novel variants. Methods and Results Thirty-nine genetically elusive LQTS cases underwent whole exome sequencing to identify CaM variants. Non-synonymous CaM variants were overrepresented significantly in this heretofore LQTS cohort (15.4%) compared to exome aggregation consortium (0.04%; p<0.0001). When the clinical sequelae of these 6 CaM-positive cases was compared to the 33 CaM-negative cases, CaM-positive cases had a more severe phenotype with an average age of onset of 8 months, an average QTc of 679 ms, and a high prevalence of cardiac arrest. Functional characterization of one novel variant, E141G-CaM, revealed an 11-fold reduction in Ca2+ binding affinity and a functionally-dominant loss of inactivation in CaV1.2, mild accentuation in NaV1.5 late current, but no effect on intracellular RyR2-mediated calcium release. Conclusions Overall, 15% of our genetically elusive LQTS cohort harbored non-synonymous variants in CaM. Genetic testing of CALM1-3 should be pursued for individuals with LQTS, especially those with early childhood cardiac arrest, extreme QT prolongation, and a negative family history. PMID:26969752

  14. Supralinear dendritic Ca(2+) signalling in young developing CA1 pyramidal cells.

    Science.gov (United States)

    Pohle, Jörg; Bischofberger, Josef

    2014-11-15

    Although Ca(2+) is critically important in activity-dependent neuronal development, not much is known about the regulation of dendritic Ca(2+) signals in developing neurons. Here, we used ratiometric Ca(2+) imaging to investigate dendritic Ca(2+) signalling in rat hippocampal pyramidal cells during the first 1-4 weeks of postnatal development. We show that active dendritic backpropagation of Nav channel-dependent action potentials (APs) evoked already large dendritic Ca(2+) transients in animals aged 1 week with amplitudes of ∼150 nm, similar to the amplitudes of ∼160 nM seen in animals aged 4 weeks. Although the AP-evoked dendritic Ca(2+) load increased about four times during the first 4 weeks, the peak amplitude of free Ca(2+) concentration was balanced by a four-fold increase in Ca(2+) buffer capacity κs (∼70 vs. ∼280). Furthermore, Ca(2+) extrusion rates increased with postnatal development, leading to a slower decay time course (∼0.2 s vs. ∼0.1 s) and more effective temporal summation of Ca(2+) signals in young cells. Most importantly, during prolonged theta-burst stimulation dendritic Ca(2+) signals were up to three times larger in cells at 1 week than at 4 weeks of age and much larger than predicted by linear summation, which is attributable to an activity-dependent slow-down of Ca(2+) extrusion. As Ca(2+) influx is four-fold smaller in young cells, the larger Ca(2+) signals are generated using four times less ATP consumption. Taken together, the data suggest that active backpropagations regulate dendritic Ca(2+) signals during early postnatal development. Remarkably, during prolonged AP firing, Ca(2+) signals are several times larger in young than in mature cells as a result of activity-dependent regulation of Ca(2+) extrusion rates.

  15. Improved thermoelectric performance of n-type Ca and Ca-Ce filled skutterudites

    Science.gov (United States)

    Thompson, Daniel R.; Liu, Chang; Ellison, Nicole D.; Salvador, James R.; Meyer, Martin S.; Haddad, Daad B.; Wang, Hsin; Cai, W.

    2014-12-01

    Thermoelectric (TE) technology for use in automotive waste heat recovery is being advanced by General Motors with support from the US Department of Energy. Skutterudites are a very promising material for this application of TE technology due to their superior mechanical properties and good TE performance. Double-filled YbxBayCo4Sb12 with ZT values around 1.1 at 750 K are the best performing n-type skutterudites produced on a large scale using an economically viable approach of melt spinning (MS) in conjunction with spark plasma sintering (SPS). Another economical production method on the tons scale, the melt quench annealing (MQA) technique, has been recently claimed by Treibacher Industrie AG, further information is available [G. Rogl et al., Acta Mater. 76, 434-448 (2014)]. A possible hurdle to commercial implementation of these materials is the use of rare earths as the fillers to reduce thermal conductivity and improve the electrical transport properties. It will be shown herein that skutterudites double-filled with Ca and Ce, both of which are lower-cost fillers, display markedly different TE properties depending on whether they are produced by MQA or MS + SPS synthesis techniques. Ca and Ce double-filled skutterudites prepared by MS + SPS have TE properties that are superior to the same compositions prepared by MQA and that are comparable to the best performing Yb and Ba filled materials. Furthermore, the results of this study suggest that the unusually poor transport properties of MQA Ca-filled skutterudites can be ascribed to deleterious secondary phases, which is contrary to reports in the literature attempting to explain these irregularities via band structure features.

  16. Improved thermoelectric performance of n-type Ca and Ca-Ce filled skutterudites

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Daniel R.; Liu, Chang; Ellison, Nicole D. [Optimal CAE, Plymouth, Michigan 48170 (United States); Salvador, James R.; Meyer, Martin S.; Haddad, Daad B. [General Motors Research and Development, Warren, Michigan 48090 (United States); Wang, Hsin; Cai, W. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-12-28

    Thermoelectric (TE) technology for use in automotive waste heat recovery is being advanced by General Motors with support from the US Department of Energy. Skutterudites are a very promising material for this application of TE technology due to their superior mechanical properties and good TE performance. Double-filled Yb{sub x}Ba{sub y}Co{sub 4}Sb{sub 12} with ZT values around 1.1 at 750 K are the best performing n-type skutterudites produced on a large scale using an economically viable approach of melt spinning (MS) in conjunction with spark plasma sintering (SPS). Another economical production method on the tons scale, the melt quench annealing (MQA) technique, has been recently claimed by Treibacher Industrie AG, further information is available [G. Rogl et al., Acta Mater. 76, 434–448 (2014)]. A possible hurdle to commercial implementation of these materials is the use of rare earths as the fillers to reduce thermal conductivity and improve the electrical transport properties. It will be shown herein that skutterudites double-filled with Ca and Ce, both of which are lower-cost fillers, display markedly different TE properties depending on whether they are produced by MQA or MS + SPS synthesis techniques. Ca and Ce double-filled skutterudites prepared by MS + SPS have TE properties that are superior to the same compositions prepared by MQA and that are comparable to the best performing Yb and Ba filled materials. Furthermore, the results of this study suggest that the unusually poor transport properties of MQA Ca-filled skutterudites can be ascribed to deleterious secondary phases, which is contrary to reports in the literature attempting to explain these irregularities via band structure features.

  17. EMRE Is a Matrix Ca2+ Sensor that Governs Gatekeeping of the Mitochondrial Ca2+ Uniporter

    Directory of Open Access Journals (Sweden)

    Horia Vais

    2016-01-01

    Full Text Available The mitochondrial uniporter (MCU is an ion channel that mediates Ca2+ uptake into the matrix to regulate metabolism, cell death, and cytoplasmic Ca2+ signaling. Matrix Ca2+ concentration is similar to that in cytoplasm, despite an enormous driving force for entry, but the mechanisms that prevent mitochondrial Ca2+ overload are unclear. Here, we show that MCU channel activity is governed by matrix Ca2+ concentration through EMRE. Deletion or charge neutralization of its matrix-localized acidic C terminus abolishes matrix Ca2+ inhibition of MCU Ca2+ currents, resulting in MCU channel activation, enhanced mitochondrial Ca2+ uptake, and constitutively elevated matrix Ca2+ concentration. EMRE-dependent regulation of MCU channel activity requires intermembrane space-localized MICU1, MICU2, and cytoplasmic Ca2+. Thus, mitochondria are protected from Ca2+ depletion and Ca2+ overload by a unique molecular complex that involves Ca2+ sensors on both sides of the inner mitochondrial membrane, coupled through EMRE.

  18. CaV1.1: The atypical prototypical voltage-gated Ca2+ channel

    Science.gov (United States)

    Bannister, Roger A.; Beam, Kurt G.

    2012-01-01

    CaV1.1 is the prototype for the other nine known CaV channel isoforms, yet it has functional properties that make it truly atypical of this group. Specifically, CaV1.1 is expressed solely in skeletal muscle where it serves multiple purposes; it is the voltage sensor for excitation-contraction (EC) coupling and it is an L-type Ca2+ channel which contributes to a form of activity-dependent Ca2+ entry that has been termed Excitation-Coupled Ca2+ Entry (ECCE). The ability of CaV1.1 to serve as voltage-sensor for EC coupling appears to be unique amongst CaV channels, whereas the physiological role of its more conventional function as a Ca2+ channel has been a matter of uncertainty for nearly 50 years. In this chapter, we discuss how CaV1.1 supports EC coupling, the possible relevance of Ca2+ entry through CaV1.1 and how alterations of CaV1.1 function can have pathophysiological consequences. PMID:22982493

  19. Differential blocking action of dihydropyridine Ca2+ antagonists on a T-type Ca2+ channel (alpha1G) expressed in Xenopus oocytes.

    Science.gov (United States)

    Furukawa, Taiji; Nukada, Toshihide; Miura, Reiko; Ooga, Kyoji; Honda, Mituyoshi; Watanabe, Suguru; Koganesawa, Satoshi; Isshiki, Takaaki

    2005-03-01

    Recent reports show that efonidipine, a dihydropyridine Ca2+ antagonist, has blocking action on T-type Ca2+ channels, which may produce favorable actions on cardiovascular systems. However, the effects of other dihydropyridine Ca2+ antagonists on T-type Ca2+ channels have not been investigated yet. Therefore, in this study, we examined the effects of dihydropyridine compounds clinically used for treatment of hypertension on a T-type Ca2+ channel subtype, alpha1G, expressed in Xenopus oocytes. These effects were compared with those on T-type Ca2+ channel. Rabbit L-type (alpha1Calpha2/deltabeta1a) or rat T-type (alpha1G) Ca2+ channel was expressed in Xenopus oocytes by injection of cRNA for each subunit. The Ba currents through expressed channels were measured by conventional 2-microelectrode voltage-clamp methods. Twelve DHPs (amlodipine, barnidipine, benidipine, cilnidipine, efonidipine, felodipine, manidipine, nicardipine, nifedipine, nilvadipine, nimodipine, nitrendipine) and mibefradil were tested. Cilnidipine, felodipine, nifedipine, nilvadipine, minodipine, and nitrendipine had little effect on the T-type channel. The blocks by drugs at 10 microM were less than 10% at a holding potential of -100 mV. The remaining 6 drugs had blocking action on the T-type channel comparable to that on the L-type channel. The blocking actions were also comparable to that by mibefradil. These results show that many dihydropyridine Ca2+ antagonists have blocking action on the alpha1G channel subtype. The action of dihydropyridine Ca2+ antagonists in clinical treatment should be evaluated on the basis of subtype selectivity.

  20. Passive transport pathways for Ca(2+) and Co(2+) in human red blood cells. (57)Co(2+) as a tracer for Ca(2+) influx.

    Science.gov (United States)

    Simonsen, Lars Ole; Harbak, Henrik; Bennekou, Poul

    2011-12-15

    The passive transport of calcium and cobalt and their interference were studied in human red cells using (45)Ca and (57)Co as tracers. In ATP-depleted cells, with the ATP concentration reduced to about 1μM, the progress curve for (45)Ca uptake at 1mM rapidly levels off with time, consistent with a residual Ca-pump activity building up at increasing [Ca(T)](c) to reach at [Ca(T)](c) about 5μmol(lcells)(-1) a maximal pump rate that nearly countermands the passive Ca influx, resulting in a linear net uptake at a low level. In ATP-depleted cells treated with vanadate, supposed to cause Ca-pump arrest, a residual pump activity is still present at high [Ca(T)](c). Moreover, vanadate markedly increases the passive Ca(2+) influx. The residual Ca-pump activity in ATP-depleted cells is fuelled by breakdown of the large 2,3-DPG pool, rate-limited by the sustainable ATP-turnover at about 40-50μmol(lcells)(-1)h(-1). The apparent Ca(2+) affinity of the Ca-pump appears to be markedly reduced compared to fed cells. The 2,3-DPG breakdown can be prevented by inhibition of the 2,3-DPG phosphatase by tetrathionate, and under these conditions the (45)Ca uptake is markedly increased and linear with time, with the unidirectional Ca influx at 1mM Ca(2+) estimated at 50-60μmol(lcells)(-1)h(-1). The Ca influx increases with the extracellular Ca(2+) concentration with a saturating component, with K(½(Ca)) about 0.3mM, plus a non-saturating component. From (45)Ca-loaded, ATP-depleted cells the residual Ca-pump can also be detected as a vanadate- and tetrathionate-sensitive efflux. The (45)Ca efflux is markedly accelerated by external Ca(2+), both in control cells and in the presence of vanadate or tetrathionate, suggesting efflux by carrier-mediated Ca/Ca exchange. The (57)Co uptake is similar in fed cells and in ATP-depleted cells (exposed to iodoacetamide), consistent with the notion that Co(2+) is not transported by the Ca-pump. The transporter is thus neither SH-group nor ATP or

  1. Oxidized CaMKII promotes asthma through the activation of mast cells

    Science.gov (United States)

    Qu, Jingjing; Do, Danh C.; Luczak, Elizabeth; Mitzner, Wayne; Anderson, Mark E.; Gao, Peisong

    2017-01-01

    Oxidation of calmodulin-dependent protein kinase II (ox-CaMKII) by ROS has been associated with asthma. However, the contribution of ox-CaMKII to the development of asthma remains to be fully characterized. Here, we tested the effect of ox-CaMKII on IgE-mediated mast cell activation in an allergen-induced mouse model of asthma using oxidant-resistant CaMKII MMVVδ knockin (MMVVδ) mice. Compared with WT mice, the allergen-challenged MMVVδ mice displayed less airway hyperresponsiveness (AHR) and inflammation. These MMVVδ mice exhibited reduced levels of ROS and diminished recruitment of mast cells to the lungs. OVA-activated bone marrow–derived mast cells (BMMCs) from MMVVδ mice showed a significant inhibition of ROS and ox-CaMKII expression. ROS generation was dependent on intracellular Ca2+ concentration in BMMCs. Importantly, OVA-activated MMVVδ BMMCs had suppressed degranulation, histamine release, leukotriene C4, and IL-13 expression. Adoptive transfer of WT, but not MMVVδ, BMMCs, reversed the alleviated AHR and inflammation in allergen-challenged MMVVδ mice. The CaMKII inhibitor KN-93 significantly suppressed IgE-mediated mast cell activation and asthma. These studies support a critical but previously unrecognized role of ox-CaMKII in mast cells that promotes asthma and suggest that therapies to reduce ox-CaMKII may be a novel approach for asthma. PMID:28097237

  2. Examining the Evidence for the Influence of Carbonate Saturation State on Benthic Foraminiferal Mg/Ca

    Science.gov (United States)

    Martin, P. A.; Lea, D. W.; McCorkle, D. C.

    2002-12-01

    Benthic foraminiferal Mg/Ca paleothermometry is based on an empirical relationship between the Mg/Ca of benthic foraminifera recovered from core tops and in situ bottom water temperatures (Rosenthal, 1997; Martin et al, in press; Lear et al, in review). While there is a tight correlation between shell Mg/Ca and temperature over a broad range of temperatures (-1 to 20 degrees C), Mg/Ca variation over the small range of deep water temperatures reveals departures from the calibration curve at low temperatures. Lower Mg/Ca values are generally associated with the deepest sites from the Atlantic and Pacific, contributing to an apparently steeper Mg/Ca-T response for abyssal benthics. The steeper response of abyssal benthics may reflect an influence of decreasing carbonate saturation with depth. Saturation related effects have already been documented for Mg in planktonic foraminifera and for other metals (Cd, Ba, and Zn) in benthic foraminifera shells (see Marchitto and ref. therein). Although it is difficult to definitively separate the effects of various environmental parameters (including temperature, depth, and relative saturation states), which often change in unison, we can use the core top Mg/Ca data to estimate the potential influence of saturation state. An alternative calibration of the benthic Mg/Ca - T relationship can be derived from core top benthic foraminifera based only on sites bathed in waters above carbonate saturation that yields a slightly smaller change in Mg/Ca per degree C (~9.5% vs. 11%) but better explains benthic Mg/Ca from the coldest sites (-1degrees C). Using this alternative Mg/Ca -T relation and a subset of data from the Ceara Rise and Ontong Java Plateau, we can estimate a maximum Mg/Ca offset attributable to saturation state. By comparing core top and downcore data, we can also address possible differences in the primary Mg-T response and carbonate saturation related effects between different genera (Cibicidoides and Uvigerina).

  3. Muscle-Type Specific Autophosphorylation of CaMKII Isoforms after Paced Contractions

    Science.gov (United States)

    Eilers, Wouter; Gevers, Wouter; van Overbeek, Daniëlle; de Haan, Arnold; Jaspers, Richard T.; Hilbers, Peter A.; van Riel, Natal; Flück, Martin

    2014-01-01

    We explored to what extent isoforms of the regulator of excitation-contraction and excitation-transcription coupling, calcium/calmodulin protein kinase II (CaMKII) contribute to the specificity of myocellular calcium sensing between muscle types and whether concentration transients in its autophosphorylation can be simulated. CaMKII autophosphorylation at Thr287 was assessed in three muscle compartments of the rat after slow or fast motor unit-type stimulation and was compared against a computational model (CaMuZclE) coupling myocellular calcium dynamics with CaMKII Thr287 phosphorylation. Qualitative differences existed between fast- (gastrocnemius medialis) and slow-type muscle (soleus) for the expression pattern of CaMKII isoforms. Phospho-Thr287 content of δA CaMKII, associated with nuclear functions, demonstrated a transient and compartment-specific increase after excitation, which contrasted to the delayed autophosphorylation of the sarcoplasmic reticulum-associated βM CaMKII. In soleus muscle, excitation-induced δA CaMKII autophosphorylation demonstrated frequency dependence (P = 0.02). In the glycolytic compartment of gastrocnemius medialis, CaMKII autophosphorylation after excitation was blunted. In silico assessment emphasized the importance of mitochondrial calcium buffer capacity for excitation-induced CaMKII autophosphorylation but did not predict its isoform specificity. The findings expose that CaMKII autophosphorylation with paced contractions is regulated in an isoform and muscle type-specific fashion and highlight properties emerging for phenotype-specific regulation of CaMKII. PMID:25054156

  4. Muscle-Type Specific Autophosphorylation of CaMKII Isoforms after Paced Contractions

    Directory of Open Access Journals (Sweden)

    Wouter Eilers

    2014-01-01

    Full Text Available We explored to what extent isoforms of the regulator of excitation-contraction and excitation-transcription coupling, calcium/calmodulin protein kinase II (CaMKII contribute to the specificity of myocellular calcium sensing between muscle types and whether concentration transients in its autophosphorylation can be simulated. CaMKII autophosphorylation at Thr287 was assessed in three muscle compartments of the rat after slow or fast motor unit-type stimulation and was compared against a computational model (CaMuZclE coupling myocellular calcium dynamics with CaMKII Thr287 phosphorylation. Qualitative differences existed between fast- (gastrocnemius medialis and slow-type muscle (soleus for the expression pattern of CaMKII isoforms. Phospho-Thr287 content of δA CaMKII, associated with nuclear functions, demonstrated a transient and compartment-specific increase after excitation, which contrasted to the delayed autophosphorylation of the sarcoplasmic reticulum-associated βM CaMKII. In soleus muscle, excitation-induced δA CaMKII autophosphorylation demonstrated frequency dependence (P = 0.02. In the glycolytic compartment of gastrocnemius medialis, CaMKII autophosphorylation after excitation was blunted. In silico assessment emphasized the importance of mitochondrial calcium buffer capacity for excitation-induced CaMKII autophosphorylation but did not predict its isoform specificity. The findings expose that CaMKII autophosphorylation with paced contractions is regulated in an isoform and muscle type-specific fashion and highlight properties emerging for phenotype-specific regulation of CaMKII.

  5. Localized calcineurin confers Ca2+-dependent inactivation on neuronal L-type Ca2+ channels.

    Science.gov (United States)

    Oliveria, Seth F; Dittmer, Philip J; Youn, Dong-ho; Dell'Acqua, Mark L; Sather, William A

    2012-10-31

    Excitation-driven entry of Ca(2+) through L-type voltage-gated Ca(2+) channels controls gene expression in neurons and a variety of fundamental activities in other kinds of excitable cells. The probability of opening of Ca(V)1.2 L-type channels is subject to pronounced enhancement by cAMP-dependent protein kinase (PKA), which is scaffolded to Ca(V)1.2 channels by A-kinase anchoring proteins (AKAPs). Ca(V)1.2 channels also undergo negative autoregulation via Ca(2+)-dependent inactivation (CDI), which strongly limits Ca(2+) entry. An abundance of evidence indicates that CDI relies upon binding of Ca(2+)/calmodulin (CaM) to an isoleucine-glutamine motif in the carboxy tail of Ca(V)1.2 L-type channels, a molecular mechanism seemingly unrelated to phosphorylation-mediated channel enhancement. But our work reveals, in cultured hippocampal neurons and a heterologous expression system, that the Ca(2+)/CaM-activated phosphatase calcineurin (CaN) is scaffolded to Ca(V)1.2 channels by the neuronal anchoring protein AKAP79/150, and that overexpression of an AKAP79/150 mutant incapable of binding CaN (ΔPIX; CaN-binding PXIXIT motif deleted) impedes CDI. Interventions that suppress CaN activity-mutation in its catalytic site, antagonism with cyclosporine A or FK506, or intracellular perfusion with a peptide mimicking the sequence of the phosphatase's autoinhibitory domain-interfere with normal CDI. In cultured hippocampal neurons from a ΔPIX knock-in mouse, CDI is absent. Results of experiments with the adenylyl cyclase stimulator forskolin and with the PKA inhibitor PKI suggest that Ca(2+)/CaM-activated CaN promotes CDI by reversing channel enhancement effectuated by kinases such as PKA. Hence, our investigation of AKAP79/150-anchored CaN reconciles the CaM-based model of CDI with an earlier, seemingly contradictory model based on dephosphorylation signaling.

  6. Isolation and characterization of higher metallofullerenes Ca@C92 and Ca@C94

    Indian Academy of Sciences (India)

    Yuliang Che; Hua Yang; Hongxiao Jin; Chunxin Lu; Ziyang Liu

    2009-05-01

    We report for the first time isolation of Ca@C92 and Ca@C94 by multi-stage highperformance liquid chromatography technique without recycling equipment. It is notable that higher metallofullerenes containing alkaline earth metal ions could be isolated although their relative yields are extremely low. Ca@C92 and Ca@C94 are also confirmed by LD-TOF mass spectrometry and characterrized by UV-Vis-NIR absorption measurements.

  7. Ca(V)1 and Ca(V)2 channels engage distinct modes of Ca(2+) signaling to control CREB-dependent gene expression.

    Science.gov (United States)

    Wheeler, Damian G; Groth, Rachel D; Ma, Huan; Barrett, Curtis F; Owen, Scott F; Safa, Parsa; Tsien, Richard W

    2012-05-25

    Activity-dependent gene expression triggered by Ca(2+) entry into neurons is critical for learning and memory, but whether specific sources of Ca(2+) act distinctly or merely supply Ca(2+) to a common pool remains uncertain. Here, we report that both signaling modes coexist and pertain to Ca(V)1 and Ca(V)2 channels, respectively, coupling membrane depolarization to CREB phosphorylation and gene expression. Ca(V)1 channels are advantaged in their voltage-dependent gating and use nanodomain Ca(2+) to drive local CaMKII aggregation and trigger communication with the nucleus. In contrast, Ca(V)2 channels must elevate [Ca(2+)](i) microns away and promote CaMKII aggregation at Ca(V)1 channels. Consequently, Ca(V)2 channels are ~10-fold less effective in signaling to the nucleus than are Ca(V)1 channels for the same bulk [Ca(2+)](i) increase. Furthermore, Ca(V)2-mediated Ca(2+) rises are preferentially curbed by uptake into the endoplasmic reticulum and mitochondria. This source-biased buffering limits the spatial spread of Ca(2+), further attenuating Ca(V)2-mediated gene expression.

  8. Preoperative CA125 as a prognostic factor in stage I epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Petri, Anette Lykke; Høgdall, Estrid; Christensen, Ib Jarle;

    2006-01-01

    was evaluated and compared with other prognostic factors (age, grade, substages, histologic type). By the Kaplan-Meier estimate we demonstrated that patients with stage I EOC and preoperative serum CA125 levels U/mL had a significantly longer survival compared to stage I EOC patients with preoperative serum...... CA125 > or = 65 U/mL (p=0.01). The results from the present study may be useful for decision making respecting postoperative chemotherapy in stage I EOC patients. Serum CA125 levels might therefore be included as a prognostic factor in future clinical trials of stage I EOC....

  9. Preoperative CA125 as a prognostic factor in stage I epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Petri, Anette Lykke; Høgdall, Estrid; Christensen, Ib Jarle

    2006-01-01

    was evaluated and compared with other prognostic factors (age, grade, substages, histologic type). By the Kaplan-Meier estimate we demonstrated that patients with stage I EOC and preoperative serum CA125 levels U/mL had a significantly longer survival compared to stage I EOC patients with preoperative serum...... CA125 > or = 65 U/mL (p=0.01). The results from the present study may be useful for decision making respecting postoperative chemotherapy in stage I EOC patients. Serum CA125 levels might therefore be included as a prognostic factor in future clinical trials of stage I EOC....

  10. Ca(2+) signalling in the Golgi apparatus.

    Science.gov (United States)

    Pizzo, Paola; Lissandron, Valentina; Capitanio, Paola; Pozzan, Tullio

    2011-08-01

    The Golgi apparatus plays a central role in lipid and protein post-translational modification and sorting. Morphologically the organelle is heterogeneous and it is possible to distinguish stacks of flat cysternae (cis- and medial Golgi), tubular-reticular networks and vesicles (trans-Golgi). These morphological differences parallel a distinct functionality with a selective distribution and complementary roles of the enzymes found in the different compartments. The Golgi apparatus has been also shown to be involved in Ca(2+) signalling: it is indeed endowed with Ca(2+) pumps, Ca(2+) release channels and Ca(2+) binding proteins and is thought to participate in determining the spatio-temporal complexity of the Ca(2+) signal within the cell, though this role is still poorly understood. Recently, it has been demonstrated that the organelle is heterogeneous in terms of Ca(2+) handling and selective reduction of Ca(2+) concentration, both in vitro and in a genetic human disease, within one of its sub-compartment results in alterations of protein trafficking within the secretory pathway and of the entire Golgi morphology. In this paper we review the available information on the Ca(2+) toolkit within the Golgi, its heterogeneous distribution in the organelle sub-compartments and discuss the implications of these characteristics for the physiopathology of the Golgi apparatus.

  11. Actinide production from the interactions of sup 40 Ca and sup 44 Ca with sup 248 Cm and a comparison with the sup 48 Ca+ sup 248 Cm system

    Energy Technology Data Exchange (ETDEWEB)

    Tuerler, A.; von Gunten, H.R. (Laboratorium fuer Radiochemie, Universitaet Bern, 3000 Bern 9 (Switzerland)); Leyba, J.D.; Hoffman, D.C.; Lee, D.M.; Gregorich, K.E.; Bennett, D.A.; Chasteler, R.M.; Gannett, C.M.; Hall, H.L.; Henderson, R.A.; Nurmia, M.J. (Nuclear Science Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States))

    1992-10-01

    Excitation functions have been measured for production of isotopes of Th through Fm in bombardments of {sup 248}Cm with 231- to 323-MeV {sup 44}Ca ions and for the production of isotopes of Th through Cm in bombardments of {sup 248}Cm with 230- to 291-MeV {sup 40}Ca ions, respectively, using radiochemical methods. Upper production cross section limits were established for nuclides that were not positively detected. The experimental data were compared with the results of previous reaction studies in the systems {sup 40}Ca+{sup 248}Cm and {sup 48}Ca+{sup 248}Cm. The half-widths of the Gaussian isotopic distributions were about 2.5 mass numbers for above-target elements and 5 to 5.5 mass numbers for below-target elements in all three systems. The majority of the cross section for the production of above-target nuclides was assigned to predominantly quasielastic reactions, whereas below-target nuclides were formed in deeply inelastic and asymmetric quasifission reactions. The maxima of the isotopic distributions were shown by others to closely follow the minimum of the potential energy surface in experiments with {sup 48}Ca, whereas in reactions with {sup 40}Ca and {sup 44}Ca we found that a transfer of 4 to 5 protons in either direction was required to reach the minimum in potential energy.

  12. LATS refining ladle slag modifying with CaO-CaF2

    Institute of Scientific and Technical Information of China (English)

    Hongming Wang; Guirong Li; Zhongming Ren; Bo Li; Xuejun Zhang; Guomin Shi

    2007-01-01

    To reduce the slag sticking onto the snorkel of the ladle during the ladle alloying treatment station (LATS) process, CaO-CaF2 (the mass ratio of CaO/CaF2 is 1:1) was employed as the modifier of the LATS refining ladle slag. The effect of CaO-CaF2 on the melting point, viscosity, and desulfurizing capability of the ladle slag was investigated. The melting point of the unmodified ladle slag is 1439°C. When adding 20wt% CaO-CaF2, the melting point is decreased to 1327°C. At 1500°C, the viscosity of the unmodified ladle slag is 6.5 Pa·s, which can be decreased lower than 2 Pa·s by adding more than 10wt% CaO-CaF2. The experimental results of desulfurization of the melts show that the desulfurizing power of the ladle slag can be enhanced by adding CaO-CaF2.

  13. By Regulating Mitochondrial Ca2+-Uptake UCP2 Modulates Intracellular Ca2+.

    Directory of Open Access Journals (Sweden)

    Lukas Jaroslaw Motloch

    Full Text Available The possible role of UCP2 in modulating mitochondrial Ca2+-uptake (mCa2+-uptake via the mitochondrial calcium uniporter (MCU is highly controversial.Thus, we analyzed mCa2+-uptake in isolated cardiac mitochondria, MCU single-channel activity in cardiac mitoplasts, dual Ca2+-transients from mitochondrial ((Ca2+m and intracellular compartment ((Ca2+c in the whole-cell configuration in cardiomyocytes of wild-type (WT and UCP2-/- mice.Isolated mitochondria showed a Ru360 sensitive mCa2+-uptake, which was significantly decreased in UCP2-/- (229.4±30.8 FU vs. 146.3±23.4 FU, P0.05 and transsarcolemmal Ca2+-influx was inhibited suggesting a possible compensatory mechanism. Additionally, we observed an inhibitory effect of ATP on mCa2+-uptake in WT mitoplasts and (Ca2+m of cardiomyocytes leading to an increase of (Ca2+c while no ATP dependent effect was observed in UCP2-/-.Our results indicate regulatory effects of UCP2 on mCa2+-uptake. Furthermore, we propose, that previously described inhibitory effects on MCU by ATP may be mediated via UCP2 resulting in changes of excitation contraction coupling.

  14. In vitro bioactivity study of TiCaPCO(N) and Ag-doped TiCaPCO(N) films in simulated body fluid.

    Science.gov (United States)

    Sukhorukova, I V; Sheveyko, A N; Kiryukhantsev-Korneev, Ph V; Levashov, E A; Shtansky, D V

    2017-01-01

    Bioactivity of multicomponent TiCaPCO(N) and Ag-doped TiCaPCO(N) films was evaluated in vitro using simulated body fluid (SBF) and compared with that of bioactive glass Biogran. The first group of films was fabricated by magnetron sputtering of composite TiС0.5 -Ti3 POx -CaO target produced via the self-propagating high-temperature synthesis (SHS) method (TiCaPCON films), after which their surface was implanted with Ag(+) ions to obtain Ag-doped TiCaPCON films. The second group of films was fabricated by pulsed electrospark deposition (PED) using SHS-produced composite TiС0.5 -Ti3 POx -CaO and TiС0.5 -Ti3 POx -CaO-Ag electrodes. After immersion in SBF, the structure and chemistry of surface were well characterized using a combination of various microanalytical techniques, such as scanning electron microscopy, X-ray diffractometry (both in conventional and grazing incidence mode), Fourier transform infrared spectroscopy, Raman spectroscopy, and glow discharge optical emission spectroscopy. The results showed that the surfaces of the TiCaPCO(N) and Ag-doped TiCaPCO(N) films were bioactive in vitro and induced the formation of an apatite layer during exposure in SBF. In the case of the magnetron-sputtered films, the apatite layer was formed over 14 days, while 28 days were needed to form CaP phase on the surface of PED-modified samples. Various factors (film structure, surface roughness, surface functional groups, surface charge, and composition, supersaturation, and near-surface local supersaturation of SBF) affecting the kinetics of bone-like apatite formation on a bioactive surface are discussed. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 193-203, 2017.

  15. Physician Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Physician Compare, which meets Affordable Care Act of 2010 requirements, helps you search for and select physicians and other healthcare professionals enrolled in...

  16. Ca-Dependent Folding of Human Calumenin

    Science.gov (United States)

    Mazzorana, Marco; Hussain, Rohanah; Sorensen, Thomas

    2016-01-01

    Human calumenin (hCALU) is a six EF-hand protein belonging to the CREC family. As other members of the family, it is localized in the secretory pathway and regulates the activity of SERCA2a and of the ryanodine receptor in the endoplasmic reticulum (ER). We have studied the effects of Ca2+ binding to the protein and found it to attain a more compact structure upon ion binding. Circular Dichroism (CD) measurements suggest a major rearrangement of the protein secondary structure, which reversibly switches from disordered at low Ca2+ concentrations to predominantly alpha-helical when Ca2+ is added. SAXS experiments confirm the transition from an unfolded to a compact structure, which matches the structural prediction of a trilobal fold. Overall our experiments suggest that calumenin is a Ca2+ sensor, which folds into a compact structure, capable of interacting with its molecular partners, when Ca2+ concentration within the ER reaches the millimolar range. PMID:26991433

  17. Thermoelasticity of CaO from first principles

    Institute of Scientific and Technical Information of China (English)

    Liu Zi-Jiang; Qi Jian-Hong; Guo Yuan; Chen Qi-Feng; Cai Ling-Cang; Yang Xiang-Dong

    2007-01-01

    The thermoelastic properties of CaO over a wide range of pressure and temperature are studied using density functional theory in the generalized gradient approximation. The transition pressure taken from the enthalpy calculations is 66.7 GPa for CaO, which accords with the experimental result very well. The athermal elastic moduli of the two phases of CaO are calculated as a function of pressure up to 200 GPa. The calculated results are in excellent agreement with existing experimental data at ambient pressure and compared favourably with other pseudopotential predictions over the pressure regime studied. It is also found that the degree of the anisotropy rapidly decreases with pressure increasing in the B1 phase, whereas it strongly increases as the pressure increases in the B2 phase. The thermodynamic properties of the B1 phase of CaO are predicted using the quasi-harmonic Debye model; the heat capacity and entropy are consistent with other previous results at zero pressure.

  18. Explicitly Correlated Methods within the ccCA Methodology.

    Science.gov (United States)

    Mahler, Andrew; Wilson, Angela K

    2013-03-12

    The prediction of energetic properties within "chemical accuracy" (1 kcal mol(-1) from well-established experiment) can be a major challenge in computational quantum chemistry due to the computational requirements (computer time, memory, and disk space) needed to achieve this level of accuracy. Methodologies such as coupled cluster with single, double, and perturbative triple excitations (CCSD(T)) combined with very large basis sets are often required to reach this level of accuracy. Unfortunately, such calculations quickly become cost prohibitive as system size increases. Our group has developed an ab initio composite method, the correlation consistent Composite Approach (ccCA), which enables such accuracy to be possible, on average, but at reduced computational cost as compared with CCSD(T) in combination with a large basis set. While ccCA has proven quite useful, computational bottlenecks still occur. In this study, the means to reduce the computational cost of ccCA without compromising accuracy by utilizing explicitly correlated methods within ccCA have been considered, and an alternative formulation is described.

  19. Concentration of Ca in blood of amateur runners using NAA

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, L.; Zamboni, C. B.; Metairon, S. [Instituto de Pesquisas Energeticas e Nucleares (IPEN / CNEN - SP) - Centro do Reator de Pesquisas Av. Professor Lineu Prestes, 2242 - 05508-000 Sao Paulo, SP (Brazil); Nunes, L. A. S.; Lourenco, T. F.; Macedo, D. V. [Universidade Estadual de Campinas - UNICAMP - Laboratorio de Bioquimica do Exercicio - LABEX Cidade Universitaria 13083-970 - Campinas, SP Brazil - Caixa-Postal: 6109 (Brazil)

    2013-05-06

    In this study the Ca levels were determined in amateur runners blood at LABEX (Laboratorio de Bioquimica do Exercicio - UNICAMP, Brazil), using Neutron Activation Analyses (NAA) technique. The range established at rest (162 - 410 mgL{sup -1}) when compared with control group (51 - 439 mgL{sup -1}) suggests that there is a dependency of these limits in the function of the adopted physical training.

  20. The functional genome of CA1 and CA3 neurons under native conditions and in response to ischemia

    Directory of Open Access Journals (Sweden)

    Rossner Moritz

    2007-10-01

    Full Text Available Abstract Background The different physiological repertoire of CA3 and CA1 neurons in the hippocampus, as well as their differing behaviour after noxious stimuli are ultimately based upon differences in the expressed genome. We have compared CA3 and CA1 gene expression in the uninjured brain, and after cerebral ischemia using laser microdissection (LMD, RNA amplification, and array hybridization. Results Profiling in CA1 vs. CA3 under normoxic conditions detected more than 1000 differentially expressed genes that belong to different, physiologically relevant gene ontology groups in both cell types. The comparison of each region under normoxic and ischemic conditions revealed more than 5000 ischemia-regulated genes for each individual cell type. Surprisingly, there was a high co-regulation in both regions. In the ischemic state, only about 100 genes were found to be differentially expressed in CA3 and CA1. The majority of these genes were also different in the native state. A minority of interesting genes (e.g. inhibinbetaA displayed divergent expression preference under native and ischemic conditions with partially opposing directions of regulation in both cell types. Conclusion The differences found in two morphologically very similar cell types situated next to each other in the CNS are large providing a rational basis for physiological differences. Unexpectedly, the genomic response to ischemia is highly similar in these two neuron types, leading to a substantial attenuation of functional genomic differences in these two cell types. Also, the majority of changes that exist in the ischemic state are not generated de novo by the ischemic stimulus, but are preexistant from the genomic repertoire in the native situation. This unexpected influence of a strong noxious stimulus on cell-specific gene expression differences can be explained by the activation of a cell-type independent conserved gene-expression program. Our data generate both novel

  1. Levels of CEA, CA153, CA199, CA724 and AFP in nipple discharge of breast cancer patients.

    Science.gov (United States)

    Zhao, Song; Mei, Yu; Wang, Yongmei; Zhu, Jiang; Zheng, Guixi; Ma, Rong

    2015-01-01

    The distinction between breast cancer and benign breast diseases with nipple discharge remains an important diagnostic challenge. The purpose of this study was to predict the potential usefulness of tumor markers in nipple discharge and to investigate the relationship of tumor markers and clinical characteristics with breast cancer.One hundred and eleven patients with nipple discharge received breast surgery from November 2013 to December 2014 were included in the study. We evaluated levels of five tumor markers (CEA, CA153, CA199, CA724 and AFP) prior to treatment. Patients were divided into two groups according to postoperative pathological results: 30 cases in breast cancer group and 81 cases in benign group. The relationships of clinical characteristics with breast cancer were investigated by multivariate analysis with a logistic regression model.It showed significant differences in levels of nipple discharge CEA (P AFP (P = 0.834) among two groups. Logistic regression analysis demonstrated complaint, age, menopause, abnormal palpable mass, CEA and CA153 were associated with breast cancer. In summary, measurements of CA199, CA724 and AFP in nipple discharge are not of great clinical value. Detecting CEA and CA153 in nipple dischargecould potentially be used for the early detection of breast cancer with in high-risk populations.

  2. SR-targeted CaMKII inhibition improves SR Ca2+ handling, but accelerates cardiac remodeling in mice overexpressing CaMKIIδC

    OpenAIRE

    Huke, Sabine; DeSantiago, Jaime; Kaetzel, Marcia A.; Mishra, Shikha; Brown, Joan H.; Dedman, John R.; Bers, Donald M.

    2010-01-01

    Cardiac myocyte overexpression of CaMKIIδC leads to cardiac hypertrophy and heart failure (HF) possibly caused by altered myocyte Ca2+ handling. A central defect might be the marked CaMKII-induced increase in diastolic sarcoplasmic reticulum (SR) Ca2+ leak which decreases SR Ca2+ load and Ca2+ transient amplitude. We hypothesized that inhibition of CaMKII near the SR membrane would decrease the leak, improve Ca2+ handling and prevent the development of contractile dysfunction and HF. To test ...

  3. Results of measuring internal Ca absorption and Ca kinetics with /sup 47/Ca in patients suffering from chronically recurrent urolithiasis

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, L.; Esther, G.; Serfling, D.; Bast, R. (Rostock Univ. (German Democratic Republic). Radiologische Klinik)

    1983-07-01

    47 patients with chronically recurrent calcium lithiasis (with between 3 and over 100 stone episodes) and an average age of 43.2 years have been examined. The Ca absorption lay between 42.7% and 90.0% of the dose, the average was 59.3% with a standard deviation of +- 12.9. This is higher than in persons with healthy kidneys. The Ca absorption is significantly lower in patients with renal insufficiency. Studies on Ca kinetics revealed turnover rates and pool sizes within the normal range.

  4. Isospin effects in {sup 40,48}Ca+{sup 40,48}Ca collisions

    Energy Technology Data Exchange (ETDEWEB)

    Henzl, V., E-mail: henzl@mit.ed [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Henzlova, D.; Kilburn, M. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Verde, G. [INFN, Sezione di Catania. 64 Via S. Sofia, I-95123, Catania (Italy); Brown, D. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Chbihi, A. [GANIL, CEA et IN2P3-CNRS, B.P. 5027, F-14076 Caen Cedex (France); Coupland, D. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Elson, J. [Departments of Chemistry and Physics, Washington University, St. Louis, MO 63130 (United States); Famiano, M. [Western Michigan University, 2229 Everett Tower, Kalamazoo, MI 49008-5252 (United States); Herlitzius, C. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Hudan, S. [Indiana Univ. Cyclotron Facility, 2401 Milo B. Sampson Lane, Bloomington, IN 47405-4001 (United States); Lee, J.; Lukyanov, S.; Lynch, W.; Rogers, A.; Sanetullaev, A. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Sobotka, L. [Departments of Chemistry and Physics, Washington University, St. Louis, MO 63130 (United States); Souza, R.T. de [Indiana Univ. Cyclotron Facility, 2401 Milo B. Sampson Lane, Bloomington, IN 47405-4001 (United States); Sun, Z.Y.; Tsang, B. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States)

    2010-03-01

    The isospin dependence of two proton correlations is studied in {sup 40}Ca+{sup 40}Ca and {sup 48}Ca+{sup 48}Ca collisions at E/A=80MeV. Measurements were performed with the HiRA detector array complemented by the 4pi Ball at NSCL. We observe a strong isospin dependence of the pp-correlation functions; however the emitting source radius extracted using the imaging technique yields no sensitivity to the isospin of the reaction system. We interpret this result as a consequence of smaller fraction of fast proton emission in the neutron rich {sup 48}Ca system.

  5. Toosendanin increases free-Ca2+ concentration in NG108-15 cells via L-type Ca2+ channels

    Institute of Scientific and Technical Information of China (English)

    Tong-hui XU; Jun DING; Yu-liang SHI

    2004-01-01

    AIM: To examine if toosendanin (TSN) affects intracellular free-Ca2+ concentration ([Ca2+]i) in neuroblastomaxglioma hybrid cells (NG108-15 cells). METHODS: The [Ca2+]i was determined by laser-scanning confocal microscopic imaging technique in which Fluo-3 was used as Ca2+ indicator. RESULTS: TSN induced an increase in resting [Ca2+]i and in high K+-evoked Ca2+ transient in differentiated NG108-15 cells. The TSN-induced increase in [Ca2+]i was dose-dependent and disappeared in CdCl2-, nifedipine-containing or Ca2+-free solution, and appeared after washing out the Ca2+ channel blockers or adding Ca2+. CONCLUSION: TSN increased [Ca2+]i in differentiated NG108-15 cells. The [Ca2+]i enhancement was due to the influx of extracellular Ca2+ and related to L-type Ca2+ channels.

  6. Ca²⁺ signals promote GLUT4 exocytosis and reduce its endocytosis in muscle cells.

    Science.gov (United States)

    Li, Q; Zhu, X; Ishikura, S; Zhang, D; Gao, J; Sun, Y; Contreras-Ferrat, A; Foley, K P; Lavandero, S; Yao, Z; Bilan, P J; Klip, A; Niu, W

    2014-07-15

    Elevating cytosolic Ca(2+) stimulates glucose uptake in skeletal muscle, but how Ca(2+) affects intracellular traffic of GLUT4 is unknown. In tissue, changes in Ca(2+) leading to contraction preclude analysis of the impact of individual, Ca(2+)-derived signals. In L6 muscle cells stably expressing GLUT4myc, the Ca(2+) ionophore ionomycin raised cytosolic Ca(2+) and caused a gain in cell surface GLUT4myc. Extra- and intracellular Ca(2+) chelators (EGTA, BAPTA-AM) reversed this response. Ionomycin activated calcium calmodulin kinase II (CaMKII), AMPK, and PKCs, but not Akt. Silencing CaMKIIδ or AMPKα1/α2 partly reduced the ionomycin-induced gain in surface GLUT4myc, as did peptidic or small molecule inhibitors of CaMKII (CN21) and AMPK (Compound C). Compared with the conventional isoenzyme PKC inhibitor Gö6976, the conventional plus novel PKC inhibitor Gö6983 lowered the ionomycin-induced gain in cell surface GLUT4myc. Ionomycin stimulated GLUT4myc exocytosis and inhibited its endocytosis in live cells. siRNA-mediated knockdown of CaMKIIδ or AMPKα1/α2 partly reversed ionomycin-induced GLUT4myc exocytosis but did not prevent its reduced endocytosis. Compared with Gö6976, Gö6983 markedly reversed the slowing of GLUT4myc endocytosis triggered by ionomycin. In summary, rapid Ca(2+) influx into muscle cells accelerates GLUT4myc exocytosis while slowing GLUT4myc endocytosis. CaMKIIδ and AMPK stimulate GLUT4myc exocytosis, whereas novel PKCs reduce endocytosis. These results identify how Ca(2+)-activated signals selectively regulate GLUT4 exocytosis and endocytosis in muscle cells.

  7. A comparison of fluorescent Ca2+ indicators for imaging local Ca2+ signals in cultured cells

    Science.gov (United States)

    Lock, Jeffrey T.; Parker, Ian

    2015-01-01

    Localized subcellular changes in Ca2+ serve as important cellular signaling elements, regulating processes as diverse as neuronal excitability and gene expression. Studies of cellular Ca2+ signaling have been greatly facilitated by the availability of fluorescent Ca2+ indicators. The respective merits of different indicators to monitor bulk changes in cellular Ca2+ levels have been widely evaluated, but a comprehensive comparison for their use in detecting and analyzing local, subcellular Ca2+ signals is lacking. Here, we evaluated several fluorescent Ca2+ indicators in the context of local Ca2+ signals (puffs) evoked by inositol 1,4,5-trisphosphate (IP3) in cultured human neuroblastoma SH-SY5Y cells, using high-speed video-microscopy. Altogether, nine synthetic Ca2+ dyes (Fluo-4, Fluo-8, Fluo-8 high affinity, Fluo-8 low affinity, Oregon Green BAPTA-1, Cal-520, Rhod-4, Asante Calcium Red, and X-Rhod-1) and three genetically-encoded Ca2+-indicators (GCaMP6-slow, -medium and -fast variants) were tested; criteria include the magnitude, kinetics, signal-to-noise ratio and detection efficiency of local Ca2+ puffs. Among these, we conclude that Cal-520 is the optimal indicator for detecting and faithfully tracking local events; that Rhod-4 is the red-emitting indicator of choice; and that none of the GCaMP6 variants are well suited for imaging subcellular Ca2+ signals. PMID:26572560

  8. Environmental novelty elicits a later theta phase of firing in CA1 but not subiculum.

    Science.gov (United States)

    Lever, Colin; Burton, Stephen; Jeewajee, Ali; Wills, Thomas J; Cacucci, Francesca; Burgess, Neil; O'Keefe, John

    2010-02-01

    The mechanism supporting the role of the hippocampal formation in novelty detection remains controversial. A comparator function has been variously ascribed to CA1 or subiculum, whereas the theta rhythm has been suggested to separate neural firing into encoding and retrieval phases. We investigated theta phase of firing in principal cells in subiculum and CA1 as rats foraged in familiar and novel environments. We found that the preferred theta phase of firing in CA1, but not subiculum, was shifted to a later phase of the theta cycle during environmental novelty. Furthermore, the amount of phase shift elicited by environmental change correlated with the extent of place cell remapping in CA1. Our results support a relationship between theta phase and novelty-induced plasticity in CA1.

  9. The solar chromosphere at high resolution with IBIS: III. Comparison of Ca II K and Ca II 854.2 nm imaging

    CERN Document Server

    Reardon, K P; Cauzzi, G

    2008-01-01

    Filtergrams obtained in Ca II H, Ca II K and H-alpha are often employed as diagnostics of the solar chromosphere. However, the vastly disparate appearance between the typical filtergrams in these different lines calls into question the nature of what is actually being observed. We investigate the lack of obvious structures of magnetic origin such as fibrils and mottles in on-disk Ca II H and K images by directly comparing a temporal sequence of classical Ca II K filtergrams with a co-spatial and co-temporal sequence of spectrally resolved Ca II 854.2 images obtained with the Interferometric Bidimensional Spectrometer (IBIS), considering the effect of both the spectral and spatial smearing. We find that the lack of fine magnetic structuring in Ca II K filtergrams, even with the narrowest available filters, is due to observational effects. Signatures of fibrils remain however in the temporal evolution of the filtergrams, in particular with the evidence of magnetic shadows around the network elements. The Ca II ...

  10. CaLB Catalyzed Conversion of ε-Caprolactone in Aqueous Medium. Part 1: Immobilization of CaLB to Microgels

    Directory of Open Access Journals (Sweden)

    Stefan Engel

    2016-10-01

    Full Text Available The enzymatic ring-opening polymerization of lactones is a method of increasing interest for the synthesis of biodegradable and biocompatible polymers. In the past it was shown that immobilization of Candida antarctica lipase B (CaLB and the reaction medium play an important role in the polymerization ability especially of medium ring size lactones like ε-caprolactone (ε-CL. We investigated a route for the preparation of compartmentalized microgels based on poly(glycidol in which CaLB was immobilized to increase its esterification ability. To find the ideal environment for CaLB, we investigated the acceptable water concentration and the accessibility for the monomer in model polymerizations in toluene and analyzed the obtained oligomers/polymers by NMR and SEC. We observed a sufficient accessibility for ε-CL to a toluene like hydrophobic phase imitating a hydrophobic microgel. Comparing free CaLB and Novozym® 435 we found that not the monomer concentration but rather the solubility of the enzyme, as well as the water concentration, strongly influences the equilibrium of esterification and hydrolysis. On the basis of these investigations, microgels of different polarity were prepared and successfully loaded with CaLB by physical entrapment. By comparison of immobilized and free CaLB, we demonstrated an effect of the hydrophobicity of the microenvironment of CaLB on its enzymatic activity.

  11. On SA, CA, and GA numbers

    CERN Document Server

    Caveney, Geoffrey; Sondow, Jonathan

    2011-01-01

    Gronwall's function $G$ is defined for $n>1$ by $G(n)=\\frac{\\sigma(n)}{n \\log\\log n}$ where $\\sigma(n)$ is the sum of the divisors of $n$. We call an integer $N>1$ a \\emph{GA1 number} if $N$ is composite and $G(N) \\ge G(N/p)$ for all prime factors $p$ of $N$. We say that $N$ is a \\emph{GA2 number} if $G(N) \\ge G(aN)$ for all multiples $aN$ of $N$. In arXiv 1110.5078, we used Robin's and Gronwall's theorems on $G$ to prove that the Riemann Hypothesis (RH) is true if and only if 4 is the only number that is both GA1 and GA2. Here, we study GA1 numbers and GA2 numbers separately. We compare them with superabundant (SA) and colossally abundant (CA) numbers (first studied by Ramanujan). We give algorithms for computing GA1 numbers; the smallest one with more than two prime factors is 183783600, while the smallest odd one is 1058462574572984015114271643676625. We find nineteen GA2 numbers $\\le 5040$, and prove that a GA2 number $N>5040$ exists if and only if RH is false, in which case $N$ is even and $>10^{8576}$.

  12. Comparative Advantage

    DEFF Research Database (Denmark)

    Zhang, Jie; Jensen, Camilla

    2007-01-01

    that are typically explained from the supply-side variables, the comparative advantage of the exporting countries. A simple model is proposed and tested. The results render strong support for the relevance of supply-side factors such as natural endowments, technology, and infrastructure in explaining international...

  13. Intermittent hypoxia in rats reduces activation of Ca2+ sparks in mesenteric arteries.

    Science.gov (United States)

    Jackson-Weaver, Olan; Osmond, Jessica M; Naik, Jay S; Gonzalez Bosc, Laura V; Walker, Benjimen R; Kanagy, Nancy L

    2015-12-01

    Ca(+) sparks are vascular smooth muscle cell (VSMC) Ca(2+)-release events that are mediated by ryanodine receptors (RyR) and promote vasodilation by activating large-conductance Ca(2+)-activated potassium channels and inhibiting myogenic tone. We have previously reported that exposing rats to intermittent hypoxia (IH) to simulate sleep apnea augments myogenic tone in mesenteric arteries through loss of hydrogen sulfide (H2S)-induced dilation. Because we also observed that H2S can increase Ca(2+) spark activity, we hypothesized that loss of H2S after IH exposure reduces Ca(2+) spark activity and that blocking Ca(2+) spark generation reduces H2S-induced dilation. Ca(2+) spark activity was lower in VSMC of arteries from IH compared with sham-exposed rats. Furthermore, depolarizing VSMC by increasing luminal pressure (from 20 to 100 mmHg) or by elevating extracellular [K(+)] increased spark activity in VSMC of arteries from sham rats but had no effect in arteries from IH rats. Inhibiting endogenous H2S production in sham arteries prevented these increases. NaHS or phosphodiesterase inhibition increased spark activity to the same extent in sham and IH arteries. Depolarization-induced increases in Ca(2+) spark activity were due to increased sparks per site, whereas H2S increases in spark activity were due to increased spark sites per cell. Finally, inhibiting Ca(2+) spark activity with ryanodine (10 μM) enhanced myogenic tone in arteries from sham but not IH rats and blocked dilation to exogenous H2S in arteries from both sham and IH rats. Our results suggest that H2S regulates RyR activation and that H2S-induced dilation requires Ca(2+) spark activation. IH exposure decreases endogenous H2S-dependent Ca(2+) spark activation to cause membrane depolarization and enhance myogenic tone in mesenteric arteries.

  14. Zebrafish CaV2.1 Calcium Channels Are Tailored for Fast Synchronous Neuromuscular Transmission

    Science.gov (United States)

    Naranjo, David; Wen, Hua; Brehm, Paul

    2015-01-01

    The CaV2.2 (N-type) and CaV2.1 (P/Q-type) voltage-dependent calcium channels are prevalent throughout the nervous system where they mediate synaptic transmission, but the basis for the selective presence at individual synapses still remains an open question. The CaV2.1 channels have been proposed to respond more effectively to brief action potentials (APs), an idea supported by computational modeling. However, the side-by-side comparison of CaV2.1 and CaV2.2 kinetics in intact neurons failed to reveal differences. As an alternative means for direct functional comparison we expressed zebrafish CaV2.1 and CaV2.2 α-subunits, along with their accessory subunits, in HEK293 cells. HEK cells lack calcium currents, thereby circumventing the need for pharmacological inhibition of mixed calcium channel isoforms present in neurons. HEK cells also have a simplified morphology compared to neurons, which improves voltage control. Our measurements revealed faster kinetics and shallower voltage-dependence of activation and deactivation for CaV2.1. Additionally, recordings of calcium current in response to a command waveform based on the motorneuron AP show, directly, more effective activation of CaV2.1. Analysis of calcium currents associated with the AP waveform indicate an approximately fourfold greater open probability (PO) for CaV2.1. The efficient activation of CaV2.1 channels during APs may contribute to the highly reliable transmission at zebrafish neuromuscular junctions. PMID:25650925

  15. Behavior of CaO and Calcium in pure Magnesium

    Institute of Scientific and Technical Information of China (English)

    HA Seong-Ho; LEE Jin-Kyu; JO Hyung-Ho; JUNG Seung-Boo; KIM Shae K.

    2006-01-01

    Mg alloys exhibit a number of good properties such as low density, good castability and high specific strength.However, molten Mg and Mg alloys are ignited without the melt protective gases during melting and casting process due to their high reactivity.The purpose of this study is to investigate effects of Ca and CaO on pure Mg through microstructure observation, ignition test and phase analysis.With increasing Ca and CaO contents, the ignition resistance of Ca or CaO added pure Mg is increased and the grains are refined.As results of XRD and EDS, CaO is reduced to Ca in CaO added pure Mg.Mg2Ca phase is formed even in 0.1 wt.%CaO added pure Mg by reduction mechanism, while Mg2Ca phase is formed over 1.35 wt.% Ca added pure Mg.

  16. Ca2+ sparks and Ca2+ glows in superior cervical ganglion neurons

    Institute of Scientific and Technical Information of China (English)

    Li-jun YAO; Cai-hong WU; Jie LIU; Zhuan ZHOU; He-ping CHENG; Gang WANG; Kun-fu OU-YANG; Chao-liang WEI; Xian-hua WANG; Shi-rong WANG; Wei YAO; Hong-ping HUANG; Jian-hong LUO

    2006-01-01

    Aim: Ca2+ release from the endoplasmic reticulum (ER) is an integral component of neuronal Ca2+ signaling. The present study is to investigate properties of local Ca2+ release events in superior cervical ganglion (SCO) neurons. Methods: Primary cultured SCO neurons were prepared from neonatal rats (P3-P7). Low concentration of caffeine was used to induce Ca2+ release from the ER Ca2+ store, and intracellular Ca2+ was recorded by high-resolution line scan confocal imaging and the Ca2+ indicator Fluo-4. Results: Two populations of local Ca2+ release events with distinct temporal characteristics were evoked by 1.5 mmol/L caffeine near the surface membrane in the soma and the neurites of SCG neurons. Brief events similar to classic Ca2+ sparks lasted a few hundreds of milliseconds, whereas long-lasting events displayed duration up to tens of seconds. Typical somatic and neurite sparks were of 0.3- and 0.52-fold increase in local Fluo-4 fluorescence, respectively. Typical Ca2+ glows were brighter (△F/F0 approximately 0.6), but were highly confined in space. The half maximum of full duration of neurite sparks was much longer than those in the soma (685 vs 381 ms). Conclusion: Co-existence of Ca2+ sparks and Ca2+ glows in SCG neurons indicates distinctive local regulation of Ca2+ release kinetics. The local Ca2+ signals of variable, site-specific temporal length may bear important implications in encoding a "memory" of the trigger signal.

  17. Ca(2+) coding and decoding strategies for the specification of neural and renal precursor cells during development.

    Science.gov (United States)

    Moreau, Marc; Néant, Isabelle; Webb, Sarah E; Miller, Andrew L; Riou, Jean-François; Leclerc, Catherine

    2016-03-01

    During embryogenesis, a rise in intracellular Ca(2+) is known to be a widespread trigger for directing stem cells towards a specific tissue fate, but the precise Ca(2+) signalling mechanisms involved in achieving these pleiotropic effects are still poorly understood. In this review, we compare the Ca(2+) signalling events that appear to be one of the first steps in initiating and regulating both neural determination (neural induction) and kidney development (nephrogenesis). We have highlighted the necessary and sufficient role played by Ca(2+) influx and by Ca(2+) transients in the determination and differentiation of pools of neural or renal precursors. We have identified new Ca(2+) target genes involved in neural induction and we showed that the same Ca(2+) early target genes studied are not restricted to neural tissue but are also present in other tissues, principally in the pronephros. In this review, we also described a mechanism whereby the transcriptional control of gene expression during neurogenesis and nephrogenesis might be directly controlled by Ca(2+) signalling. This mechanism involves members of the Kcnip family such that a change in their binding properties to specific DNA sites is a result of Ca(2+) binding to EF-hand motifs. The different functions of Ca(2+) signalling during these two events illustrate the versatility of Ca(2+) as a second messenger. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Automated analysis of calcium spiking profiles with CaSA software: two case studies from root-microbe symbioses.

    Science.gov (United States)

    Russo, Giulia; Spinella, Salvatore; Sciacca, Eva; Bonfante, Paola; Genre, Andrea

    2013-12-26

    Repeated oscillations in intracellular calcium (Ca2+) concentration, known as Ca2+ spiking signals, have been described in plants for a limited number of cellular responses to biotic or abiotic stimuli and most notably the common symbiotic signaling pathway (CSSP) which mediates the recognition by their plant hosts of two endosymbiotic microbes, arbuscular mycorrhizal (AM) fungi and nitrogen fixing rhizobia. The detailed analysis of the complexity and variability of the Ca2+ spiking patterns which have been revealed in recent studies requires both extensive datasets and sophisticated statistical tools. As a contribution, we have developed automated Ca2+ spiking analysis (CaSA) software that performs i) automated peak detection, ii) statistical analyses based on the detected peaks, iii) autocorrelation analysis of peak-to-peak intervals to highlight major traits in the spiking pattern.We have evaluated CaSA in two experimental studies. In the first, CaSA highlighted unpredicted differences in the spiking patterns induced in Medicago truncatula root epidermal cells by exudates of the AM fungus Gigaspora margarita as a function of the phosphate concentration in the growth medium of both host and fungus. In the second study we compared the spiking patterns triggered by either AM fungal or rhizobial symbiotic signals. CaSA revealed the existence of different patterns in signal periodicity, which are thought to contribute to the so-called Ca2+ signature. We therefore propose CaSA as a useful tool for characterizing oscillatory biological phenomena such as Ca2+ spiking.

  19. Defective maintenance of intracellular Ca2+ homeostasis is linked to increased muscle fatigability in the MG29 null mice

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Mitsugumin 29 (MG29) is a transmembrane protein that is normally found in the triad junction of skeletal muscle. Our previous studies have shown that targeted deletion of mg29 from the skeletal muscle resulted in abnormality of the triad junction structure, and also increased susceptibility to muscle fatigue. To elucidate the basis of these effects, we investigated the properties of Ca2+-uptake and -release in toxin-skinned Extensor Digitorium Longus (EDL) muscle fibers from control and mg29 knockout mice. Compared with the control muscle, submaximal Ca2+-uptake into the sarcoplasmic reticulum (SR) was slower and the storage of Ca2+ inside the SR was less in the mutant muscle, due to increased leakage process-of Ca2+ movement across the SR. The leakage pathway is associated with the increased sensitivity of Ca2+/caffeine -induced Ca2+ release to myoplasmic Ca2+. Therefore, the increased fatigability of mutant EDL muscles can result from a combination of a slowing of Ca2+ uptake, modification of Ca2+-induced Ca2+ release (CICR), and a reduction in total SR Ca2+ content.

  20. Nitric oxide enhances increase in cytosolic Ca(2+) and promotes nicotine-triggered MAPK pathway in PC12 cells.

    Science.gov (United States)

    Kajiwara, Aya; Tsuchiya, Yukihiro; Takata, Tsuyoshi; Nyunoya, Mayumi; Nozaki, Naohito; Ihara, Hideshi; Watanabe, Yasuo

    2013-11-01

    The purpose of this study was to investigate the roles of neuronal nitric oxide synthase (nNOS), Ca(2+)/calmodulin (CaM)-dependent protein kinases (CaMKs), and protein kinase C (PKC) in nicotine-induced extracellular signal-regulated kinases 1 and 2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) activation. Treatment with nicotine stimulated ERK1/2 and p38 MAPK phosphorylation in the PC12 cells expressing nNOS (NPC12 cells) as compared with that in control PC12 cells. An inhibitor of L-type voltage-sensitive Ca(2+) channel suppressed the nicotine-induced phosphorylation of p38 MAPK. The inhibition of CaMK-kinase, the upstream activator of CaMKI and CaMKIV, did not inhibit the enhanced their phosphorylation. ERK1/2 phosphorylation was attenuated by inhibitors of p38 MAPK, PKC, and MAPK-kinase 1/2, indicating the involvement of these protein kinases upstream of ERK1/2. Furthermore, we found that nNOS expression enhances the nicotine-induced increase in the intracellular concentration of Ca(2+), using the Ca(2+)-sensitive fluorescent probe Fura2. These data suggest that NO promotes nicotine-triggered Ca(2+) transient in PC12 cells to activate possibly CaMKII, leading to sequential phosphorylation of p38 MAPK and ERK1/2.

  1. Novel Au/CaIn2S4 nanocomposites with plasmon-enhanced photocatalytic performance under visible light irradiation

    Science.gov (United States)

    Li, Jie; Meng, Suci; Wang, Tianyong; Xu, Qing; Shao, Leqiang; Jiang, Deli; Chen, Min

    2017-02-01

    A series of Au/CaIn2S4 nanocomposites with different Au contents were prepared by a simple photoreduction process. Under visible light irradiation, the as-prepared Au/CaIn2S4 nanocomposites exhibited plasmon-enhanced photocatalytic activity for the degradation of methylene blue (MB) compared to that of bare CaIn2S4. The sample with 4 wt% Au hybridized CaIn2S4 exhibited the highest photocatalytic efficiency for MB degradation compared with those of the other nanocomposites. The mechanism for improving the photocatalytic performance of the Au/CaIn2S4 nanocomposites was proposed by using the photoluminescence measurement and electrochemical analyses. The enhanced photocatalytic performance could be attributed to the high separation efficiency of the photogenerated electron-hole pairs. This work could provide a new insight into the fabrication of CaIn2S4-based plasmonic photocatalysts with enhanced performance.

  2. Effects of local anesthetics and hemicholinium-3 on 45-Ca efflux in barnacle muscle fibers.

    Science.gov (United States)

    Chen, S S

    1975-04-01

    Benzocaine, which occurs in the uncharged form in the physiological range of pH, caused inhibition of 45-Ca efflux in branacle muscle fibers. By contrast, in the presence of a low external Ca-2+ concentration it produced stimulation of the efflux. Both the inhibitory and stimulatory actions of benzocaine appeared to be less potent than those of procaine. Hemicholinium-3 (HC-3), on the other hand, which exists only in the charged form, caused a large stimulation of the 45-Ca efflux following microinjection, and the potency of this action was found to be at least 10 times greater than that of procaine. External application of HC-3 produced inhibition occasionally. Effects of tetracaine were similar to those produced by procaine; however, its inhibitory action was greater in more alkaline solution, which is the opposite of that observed with procaine. Lidocaine produced a less consistent effect than procaine; the inhibitory action of the former was less potent but the stimulatory action of the two anesthetics were comparable, p-Aminobenzoic acid was without effect on 45-Ca efflux. These results indicate that both the charged and uncharged forms of local anesthetics are capable of causing stimulatory and inhibitory effects on 45-Ca efflux in barnacle muscle fibers, and that the inhibition produced is the result of action on the CA-Ca exchange system whereas the stimulation is the result of release of Ca from internal storage sites.

  3. The Improvement of Recycled Newsprint Properties by In-situ CaCO3 Loading

    Directory of Open Access Journals (Sweden)

    Yung Bum Seo

    2014-08-01

    Full Text Available In-situ CaCO3 loading of old newspaper (ONP fiber furnish was studied as a method to improve the properties of recycled newsprint paper. The effects of in-situ loading on the morphological and physical properties of ONP furnish were examined comparatively with conventional loading methods (addition of ground or precipitated CaCO3, without and with pre-flocculation treatment. The effective residual ink content (ERIC and macro sticky content began to decrease as soon as the in-situ CaCO3 formation started by the injection of carbon dioxide to the reaction tank, where the ONP furnish and calcium oxide mixture was agitated in high shear. When the reaction finished at pH 7, there were no more decreases of ERIC value and sticky content. Improvement of first pass retention and brightness was significant for the in-situ CaCO3 loading method. The decrease in breaking length with the addition of CaCO3 in the in-situ formation method was equivalent to or slightly lower than that of the CaCO3 pre-flocculation method, which is a method well known to give higher strength properties. Optical images from the FlowCAM® dynamic imaging particle analyzer showed strongly attached organic (fines and inorganic (CaCO3 materials in the in-situ CaCO3 loading method.

  4. Input-to-output transformation in a model of the rat hippocampal CA1 network.

    Science.gov (United States)

    Olypher, Andrey V; Lytton, William W; Prinz, Astrid A

    2012-01-01

    Here we use computational modeling to gain new insights into the transformation of inputs in hippocampal field CA1. We considered input-output transformation in CA1 principal cells of the rat hippocampus, with activity synchronized by population gamma oscillations. Prior experiments have shown that such synchronization is especially strong for cells within one millimeter of each other. We therefore simulated a one-millimeter ıt patch of CA1 with 23,500 principal cells. We used morphologically and biophysically detailed neuronal models, each with more than 1000 compartments and thousands of synaptic inputs. Inputs came from binary patterns of spiking neurons from field CA3 and entorhinal cortex (EC). On average, each presynaptic pattern initiated action potentials in the same number of CA1 principal cells in the patch. We considered pairs of similar and pairs of distinct patterns. In all the cases CA1 strongly separated input patterns. However, CA1 cells were considerably more sensitive to small alterations in EC patterns compared to CA3 patterns. Our results can be used for comparison of input-to-output transformations in normal and pathological hippocampal networks.

  5. The structure of horseradish peroxidase C characterized as a molten globule state after Ca(2+) depletion.

    Science.gov (United States)

    Szigeti, Krisztián; Smeller, László; Osváth, Szabolcs; Majer, Zsuzsanna; Fidy, Judit

    2008-12-01

    The structure and activity of native horseradish peroxidase C (HRP) is stabilized by two bound Ca(2+) ions. Earlier studies suggested a critical role of one of the bound Ca(2+) ions but with conflicting conclusions concerning their respective importance. In this work we compare the native and totally Ca(2+)-depleted forms of the enzyme using pH-, pressure-, viscosity- and temperature-dependent UV absorption, CD, H/D exchange-FTIR spectroscopy and by binding the substrate benzohydroxamic acid (BHA). We report that Ca(2+)-depletion does not change the alpha helical content of the protein, but strongly modifies the tertiary structure and dynamics to yield a homogeneously loosened molten globule-like structure. We relate observed tertiary changes in the heme pocket to changes in the dipole orientation and coordination of a distal water molecule. Deprotonation of distal His42, linked to Asp43, itself coordinated to the distal Ca(2+), perturbs a H-bonding network connecting this Ca(2+) to the heme crevice that involves the distal water. The measured effects of Ca(2)(+) depletion can be interpreted as supporting a structural role for the distal Ca(2+) and for its enhanced significance in finetuning the protein structure to optimize enzyme activity.

  6. Barnidipine block of L-type Ca(2+) channel currents in rat ventricular cardiomyocytes.

    Science.gov (United States)

    Wegener, J W; Meyrer, H; Rupp, J; Nawrath, H

    2000-08-01

    The effects of barnidipine and nifedipine on L-type Ca(2+) current (I(Ca(L))) were investigated in ventricular cardiomyocytes from rats. Both barnidipine and nifedipine reduced I(Ca(L)) in a concentration and voltage dependent manner; the EC(50) were 80 and 130 nM at a holding potential of -80 mV, respectively, and 18 and 6 nM at -40 mV, respectively. Both drugs induced a leftward shift of the steady-state inactivation curve of I(Ca(L)). Using a twin pulse protocol, the relationships between the amount of block of I(Ca(L)) by either drug, seen during the second pulse, and the length of the first pulse were described by monoexponential functions reflecting onset of block, dependent on drug concentration. The onset of block by barnidipine was three times faster than that by nifedipine. With both drugs, recovery of I(Ca(L)) was 50 times slower than under control conditions and described by monoexponential functions reflecting offset of block (independent of drug concentration). The offset of block with barnidipine was three times slower than that with nifedipine. The time constants of block and unblock of I(Ca(L)) by both drugs were used to calculate binding and unbinding and to predict their effects at two frequencies. It is suggested that barnidipine exhibits a higher affinity to the inactivated Ca(2+) channel state as compared to nifedipine.

  7. Magnetic Field Effects on CaCO3 Precipitation Process in Hard Water

    Directory of Open Access Journals (Sweden)

    Nelson Saksono

    2010-10-01

    Full Text Available Magnetic treatment is applied as physical water treatment for scale prevention especially CaCO3, from hard water in piping equipment by reducing its hardness.Na2CO3 and CaCl2 solution sample was used in to investigate the magnetic fields influence on the formation of particle of CaCO3. By changing the strength of magnetic fields, exposure time and concentration of samples solution, this study presents quantitative results of total scale deposit, total precipitated CaCO3 and morphology of the deposit. This research was run by comparing magnetically and non-magnetically treated  samples. The results showed an increase of deposits formation rate and total number of precipitated CaCO3 of magnetically treated samples. The increase of concentration solution sample will also raised the deposit under magnetic  field. Microscope images showed a greater number but smaller size of CaCO3 deposits form in magnetically treated samples, and aggregation during the processes. X-ray diffraction (XRD analysis showed that magnetically samples were dominated by calcite. But, there was a significant decrease of calcite’s peak intensities from magnetized  samples that indicated the decrease of the amount of calcite and an increase of total amorphous of deposits. This result  showed that magnetization of hard water leaded to the decreasing of ion Ca2+ due to the increasing of total CaCO3 precipitation process.

  8. Regulation of cardiac myocyte contractility by phospholemman: Na+/Ca2+ exchange versus Na+ -K+ -ATPase.

    Science.gov (United States)

    Song, Jianliang; Zhang, Xue-Qian; Wang, JuFang; Cheskis, Ellina; Chan, Tung O; Feldman, Arthur M; Tucker, Amy L; Cheung, Joseph Y

    2008-10-01

    Phospholemman (PLM) regulates cardiac Na(+)/Ca(2+) exchanger (NCX1) and Na(+)-K(+)-ATPase in cardiac myocytes. PLM, when phosphorylated at Ser(68), disinhibits Na(+)-K(+)-ATPase but inhibits NCX1. PLM regulates cardiac contractility by modulating Na(+)-K(+)-ATPase and/or NCX1. In this study, we first demonstrated that adult mouse cardiac myocytes cultured for 48 h had normal surface membrane areas, t-tubules, and NCX1 and sarco(endo)plasmic reticulum Ca(2+)-ATPase levels, and retained near normal contractility, but alpha(1)-subunit of Na(+)-K(+)-ATPase was slightly decreased. Differences in contractility between myocytes isolated from wild-type (WT) and PLM knockout (KO) hearts were preserved after 48 h of culture. Infection with adenovirus expressing green fluorescent protein (GFP) did not affect contractility at 48 h. When WT PLM was overexpressed in PLM KO myocytes, contractility and cytosolic Ca(2+) concentration ([Ca(2+)](i)) transients reverted back to those observed in cultured WT myocytes. Both Na(+)-K(+)-ATPase current (I(pump)) and Na(+)/Ca(2+) exchange current (I(NaCa)) in PLM KO myocytes rescued with WT PLM were depressed compared with PLM KO myocytes. Overexpressing the PLMS68E mutant (phosphomimetic) in PLM KO myocytes resulted in the suppression of I(NaCa) but had no effect on I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the PLMS68E mutant were depressed compared with PLM KO myocytes overexpressing GFP. Overexpressing the PLMS68A mutant (mimicking unphosphorylated PLM) in PLM KO myocytes had no effect on I(NaCa) but decreased I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the S68A mutant were similar to PLM KO myocytes overexpressing GFP. We conclude that at the single-myocyte level, PLM affects cardiac contractility and [Ca(2+)](i) homeostasis primarily by its direct

  9. Comparative hemorheology

    OpenAIRE

    Başkurt, Oğuz K.; Meiselman, Herbert J.

    2013-01-01

    Comparative data on blood composition and blood flow properties indicate different levels of interspecies variation for several parameters. Hematocrit and hemoglobin levels have relatively low variability among mammals, while mean cell volume and red blood cell (RBC) count are more variable. There is also a difference of variability between high and low shear rate blood viscosity in mammals, with low shear rate viscosity having a higher degree of interspecies variation. This observation paral...

  10. 19 CFR 19.9 - General order, abandoned, and seized merchandise.

    Science.gov (United States)

    2010-04-01

    ... electronic equivalent as authorized by Customs, to cover the proprietor's receipt of the merchandise and its... designated by the port director or an electronic equivalent as authorized by Customs. (b) Recording and... 19 Customs Duties 1 2010-04-01 2010-04-01 false General order, abandoned, and seized...

  11. 22 CFR 19.9-3 - Computation and payment of pension to former spouse.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Computation and payment of pension to former... Computation and payment of pension to former spouse. (a) A pension to a former spouse is paid monthly on the... for a pension or any combination of pensions to former spouses of any one principal which exceeds the...

  12. Age-dependent changes in diastolic Ca2+ and Na+ concentrations in dystrophic cardiomyopathy: Role of Ca2+ entry and IP3

    Science.gov (United States)

    Mijares, Alfredo; Altamirano, Francisco; Kolster, Juan; Adams, José A.; López, José R.

    2014-01-01

    Duchenne muscular dystrophy (DMD) is a lethal X-inherited disease caused by dystrophin deficiency. Besides the relatively well characterized skeletal muscle degenerative processes, DMD is also associated with a dilated cardiomyopathy that leads to progressive heart failure at the end of the second decade. The aim of the present study was to characterize the diastolic Ca2+ concentration ([Ca2+]d) and diastolic Na+ concentration ([Na+]d) abnormalities in cardiomyocytes isolated from 3-, 6-, 9-, and 12-month old mdx mice using ion-selective microelectrodes. In addition, the contributions of gadolinium (Gd3+)-sensitive Ca2+ entry and inositol triphosphate (IP3) signaling pathways in abnormal [Ca2+]d and [Na+]d were investigated. Our results showed an age-dependent increase in both [Ca2+]d and [Na+]d in dystrophic cardiomyocytes compared to those isolated from age-matched wt mice. Gd3+ treatment significantly reduced both [Ca2+]d and [Na+]d at all ages. In addition, blockade of the IP3-pathway with either U-73122 or xestospongin C significantly reduced ion concentrations in dystrophic cardiomyocytes. Co-treatment with U-73122 and Gd3+ normalized both [Ca2+]d and [Na+]d at all ages in dystrophic cardiomyocytes. These data showed that loss of dystrophin in mdx cardiomyocytes produced an age-dependent intracellular Ca2+ and Na+ overload mediated at least in part by enhanced Ca2+ entry through Gd3+ sensitive transient receptor potential channels (TRPC), and by IP3 receptors. PMID:25242522

  13. Study on Roasting Decomposition of Mixed Rare Earth Concentrate in CaO-NaCl-CaCl2

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The decomposed process of bastnaesite, monazite and mixed rare earth concentrate in CaO-CaCl-CaCl2 was studied by means of TG-DTA method. The relationship among decomposition ratio, roasting temperature, and CaO-NaCl addition was studied by the quadratic regression orthogonal analysis, and then the regression equation was obtained. Through analysis, the optimum process conditions of mixed rare earth concentrate decomposed by CaO-CaCl-CaCl2 were obtained as follows: roasting temperature: 700 ℃, CaO addition: 15%, NaCl-CaCl2 addition: 10%, roasting time: 60 min, the decomposition ratio: 91.3%.

  14. Aging and CaMKII Alter Intracellular Ca2+ Transients and Heart Rhythm in Drosophila melanogaster

    Science.gov (United States)

    Santalla, Manuela; Valverde, Carlos A.; Harnichar, Ezequiel; Lacunza, Ezequiel; Aguilar-Fuentes, Javier; Mattiazzi, Alicia; Ferrero, Paola

    2014-01-01

    Aging is associated to disrupted contractility and rhythmicity, among other cardiovascular alterations. Drosophila melanogaster shows a pattern of aging similar to human beings and recapitulates the arrhythmogenic conditions found in the human heart. Moreover, the kinase CaMKII has been characterized as an important regulator of heart function and an arrhythmogenic molecule that participate in Ca2+ handling. Using a genetically engineered expressed Ca2+ indicator, we report changes in cardiac Ca2+ handling at two different ages. Aging prolonged relaxation, reduced spontaneous heart rate (HR) and increased the occurrence of arrhythmias, ectopic beats and asystoles. Alignment between Drosophila melanogaster and human CaMKII showed a high degree of conservation and indicates that relevant phosphorylation sites in humans are also present in the fruit fly. Inhibition of CaMKII by KN-93 (CaMKII-specific inhibitor), reduced HR without significant changes in other parameters. By contrast, overexpression of CaMKII increased HR and reduced arrhythmias. Moreover, it increased fluorescence amplitude, maximal rate of rise of fluorescence and reduced time to peak fluorescence. These results suggest that CaMKII in Drosophila melanogaster acts directly on heart function and that increasing CaMKII expression levels could be beneficial to improve contractility. PMID:25003749

  15. Regulated release of Ca2+ from respiring mitochondria by Ca2+/2H+ antiport.

    Science.gov (United States)

    Fiskum, G; Lehninger, A L

    1979-07-25

    Simultaneous measurements of oxygen consumption and transmembrane transport of Ca2+, H+, and phosphate show that the efflux of Ca2+ from respiring tightly coupled rat liver mitochondria takes place by an electroneutral Ca2+/2H+ antiport process that is ruthenium red-insensitive and that is regulated by the oxidation-reduction state of the mitochondrial pyridine nucleotides. When mitochondrial pyridine nucleotides are kept in a reduced steady state, the efflux of Ca2+ is inhibited; when they are in an oxidized state, Ca2+ efflux is activated. These processes were demonstrated by allowing phosphate-depleted mitochondria respiring on succinate in the presence of rotenone to take up Ca2+ from the medium. Upon subsequent addition of ruthenium red to block Ca2+ transport via the electrophoretic influx pathway, and acetoacetate, to bring mitochondrial pyridine nucleotides into the oxidized state, Ca2+ efflux and H+ influx ensued. The observed H+ influx/Ca2+ efflux ratio was close to the value 2.0 predicted for the operation of an electrically neutral Ca2+/2H+ antiport process.

  16. Ischemic damage in hippocampal CA1 is dependent on glutamate release and intact innervation from CA3

    DEFF Research Database (Denmark)

    Benveniste, H; Jørgensen, M B; Sandberg, M

    1989-01-01

    The removal of glutamatergic afferents to CA1 by destruction of the CA3 region is known to protect CA1 pyramidal cells against 10 min of transient global ischemia. To investigate further the pathogenetic significance of glutamate, we measured the release of glutamate in intact and CA3-lesioned CA...

  17. EnviroAtlas - Fresno, CA - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Fresno, CA EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  18. Role of Ca++ in Shoot Gravitropism. [avena

    Science.gov (United States)

    Rayle, D. L.

    1985-01-01

    A cornerstone in the argument that Ca(2+) levels may regulate growth is the finding the EGTA promotes straight growth. The usual explanation for these results is that Ca(2+) chelation from cell walls results in wall loosening and thus accelerated straight growth. The ability of frozen-thawed Avena coleoptile tissue (subjected to 15g tension) to extend in response to EGTA and Quin II was examined. The EGTA when applied in weakly buffered (i.e., 0.1mM) neutral solutions initiates rapid extension. When the buffer strength is increased, similar concentrations of EGTA produce no growth response. This implies when EGTA liberated protons are released upon Ca(2+) chelation they can either initiate acid growth (low buffer conditions) or if consumed (high buffer conditions) have no effect. Thus Ca(2+) chelation in itself apparently does not result in straight growth.

  19. CaMath user`s guide

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Ben-chin; Daly, B.

    1994-07-13

    CaMath is an external Mathematica package which can be loaded into Mathematica by a user. CaMath consists of a special set of channel access functions which provides the Mathematica users with easy and flexible access of channel information across the IOC networks. It also provides a complete set of process variable event monitoring functions. The available functions for CaMath, their functionality, and their syntax are described herein. This document also gives examples how a Mathematica user can interface to channel access devices. It is assumed that the user is already familiar with using Mathematica. Few examples of Mathematica module of using CaMath functions are also given in this document.

  20. Mg/Ca and Sr/Ca as novel geochemical proxies for understanding sediment transport processes within coral reefs

    Science.gov (United States)

    Gacutan, J.; Vila-Concejo, A.; Nothdurft, L. D.; Fellowes, T. E.; Cathey, H. E.; Opdyke, B. N.; Harris, D. L.; Hamylton, S.; Carvalho, R. C.; Byrne, M.; Webster, J. M.

    2017-10-01

    Sediment transport is a key driver of reef zonation and biodiversity, where an understanding of sediment dynamics gives insights into past reef processes and allows the prediction of geomorphic responses to changing environmental conditions. However, modal conditions within the back-reef seldom promote sediment transport, hence direct observation is inherently difficult. Large benthic foraminifera (LBF) have previously been employed as 'tracers' to infer sediment transport pathways on coral reefs, as their habitat is largely restricted to the algal flat and post-mortem, their calcium carbonate test is susceptible to sediment transport forces into the back-reef. Foraminiferal test abundance and post-depositional test alteration have been used as proxies for sediment transport, although the resolution of these measures becomes limited by low test abundance and the lack of variation within test alteration. Here we propose the novel use of elemental ratios as a proxy for sediment transport. Two species, Baculogypsina sphaerulata and Calcarina capricornia, were analysed using a taphonomic index within One Tree and Lady Musgrave reefs, Great Barrier Reef (Australia). Inductively coupled plasma-atomic emission spectrometry (ICP-AES) was used to determine Mg/Ca and Sr/Ca and these ratios were compared with taphonomic data. Decreases in test Mg/Ca accompany increases in Sr/Ca in specimens from algal-flat to lagoonal samples in both species, mirroring trends indicated by taphonomic values, therefore indicating a relationship with test alteration. To delineate mechanisms driving changes in elemental ratios, back-scattered electron (BSE) images, elemental mapping and in situ quantitative spot analyses by electron microprobe microanalysis (EPMA) using wavelength dispersive X-ray spectrometers (WDS) were performed on un-altered algal flat and heavily abraded tests for both species. EPMA analyses reveal heterogeneity in Mg/Ca between spines and the test wall, implying the loss of

  1. Progress towards a MOT for CaF

    Science.gov (United States)

    Hemmerling, Boerge; Chae, Eunmi; Drayna, Garrett K.; Hutzler, Nicholas R.; Ravi, Aakash; Ketterle, Wolfgang; Collopy, Alejandra; Hummon, Matthew; Stuhl, Benjamin; Yeo, Mark; Ye, Jun; Doyle, John M.

    2014-05-01

    We report on progress toward a magneto-optical trap (MOT) of CaF molecules. While following the same essential approach as that used to laser cool SrF and YO, we are developing direct MOT loading from a 2-stage cryogenic buffer gas beam (CBGB) source. This source has a lower forward velocity compared to the hydrodynamic CBGB source that was employed with SrF and YO. We report the creation of the first CBGB loaded MOTs, without the use of a Zeeman slower, for Ho, Yb, Er, and Tm. The slower initial beam velocity of the two-stage CBGB should aid in MOT loading of molecules, which have inherently low MOT capture velocities (~ 10 m/s). We plan to implement an AC-MOT for CaF, and report on theoretical studies and experimental progress toward that goal.

  2. Generating a Magellanic star cluster catalog with ASteCA

    Science.gov (United States)

    Perren, G. I.; Piatti, A. E.; Vázquez, R. A.

    2016-08-01

    An increasing number of software tools have been employed in the recent years for the automated or semi-automated processing of astronomical data. The main advantages of using these tools over a standard by-eye analysis include: speed (particularly for large databases), homogeneity, reproducibility, and precision. At the same time, they enable a statistically correct study of the uncertainties associated with the analysis, in contrast with manually set errors, or the still widespread practice of simply not assigning errors. We present a catalog comprising 210 star clusters located in the Large and Small Magellanic Clouds, observed with Washington photometry. Their fundamental parameters were estimated through an homogeneous, automatized and completely unassisted process, via the Automated Stellar Cluster Analysis package ( ASteCA). Our results are compared with two types of studies on these clusters: one where the photometry is the same, and another where the photometric system is different than that employed by ASteCA.

  3. Radiative emission of solar features in Ca II K

    CERN Document Server

    Criscuoli, S; Fontenla, J; Giorgi, F; Rast, M; Solanki, S; Uitenbroek, H

    2010-01-01

    We investigated the radiative emission of different types of solar features in the spectral range of the Ca II K line. We analyzed full-disk 2k x 2k observations from the PSPT Precision Solar Photometric Telescope. The data were obtained by using three narrow-band interference filters that sample the Ca II K line with different pass bands. Two filters are centered in the line core, the other in the red wing of the line. We measured the intensity and contrast of various solar features, specifically quiet Sun (inter-network), network, enhanced network, plage, and bright plage (facula) regions. Moreover, we compared the results obtained with those derived from the numerical synthesis performed for the three PSPT filters with a widely used radiative code on a set of reference semi-empirical atmosphere models.

  4. Nanosecond UV lasers stimulate transient Ca2+ elevations in human hNT astrocytes

    Science.gov (United States)

    Raos, B. J.; Graham, E. S.; Unsworth, C. P.

    2017-06-01

    Objective. Astrocytes respond to various stimuli resulting in intracellular Ca2+ signals that can propagate through organized functional networks. Recent literature calls for the development of techniques that can stimulate astrocytes in a fast and highly localized manner to emulate more closely the characteristics of astrocytic Ca2+ signals in vivo. Approach. In this article we demonstrate, for the first time, how nanosecond UV lasers are capable of reproducibly stimulating Ca2+ transients in human hNT astrocytes. Main results. We report that laser pulses with a beam energy of 4-29 µJ generate transient increases in cytosolic Ca2+. These Ca2+ transients then propagate to adjacent astrocytes as intercellular Ca2+ waves. Significance. We propose that nanosecond laser stimulation provides a valuable tool for enabling the study of Ca2+ dynamics in human astrocytes at both a single cell and network level. Compared to previously developed techniques nanosecond laser stimulation has the advantage of not requiring loading of photo-caged or -sensitising agents, is non-contact, enables stimulation with a high spatiotemporal resolution and is comparatively cost effective.

  5. CA Investment Casting Process of Complex Castings

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    CA (Computer aided) investment casting technique used in superalloy castings of aerospace engine parts was presented. CA investment casting integrated computer application, RP (Rapid Prototyping) process, solidification simulation and investment casting process. It broke the bottle neck of making metal die. Solid model of complex parts were produced by UGII or other software, then translated into STL(Stereolithography) file, after RP process of SLS(Selective Laser Sintering), wax pattern used in investment ...

  6. YouthCaN 2001 / Sirje Janikson

    Index Scriptorium Estoniae

    Janikson, Sirje

    2001-01-01

    Aprillis 2001 toimus keskkonnateemaline õpilaskonverents YouthCaN 2001 Ameerika Loodusajaloo Muuseumis New Yorkìs. 35 seminarist ühe viis läbi Tartu Noorte Loodusmaja geoloogia ja keskkonnaringi esindus, tutvustati loodusmaja keskkonnaprojekte ja räägiti keskkonnaalaste veebilehtede koostamise kogemustest. YouthCaN (Youth Communicating and Networking) on rahvusvaheline noorte organisatsioon, mis vahendab kogemusi ja uusi ideid elukeskkonnast huvitatud noorte hulgas

  7. YouthCaN 2001 / Sirje Janikson

    Index Scriptorium Estoniae

    Janikson, Sirje

    2001-01-01

    Aprillis 2001 toimus keskkonnateemaline õpilaskonverents YouthCaN 2001 Ameerika Loodusajaloo Muuseumis New Yorkìs. 35 seminarist ühe viis läbi Tartu Noorte Loodusmaja geoloogia ja keskkonnaringi esindus, tutvustati loodusmaja keskkonnaprojekte ja räägiti keskkonnaalaste veebilehtede koostamise kogemustest. YouthCaN (Youth Communicating and Networking) on rahvusvaheline noorte organisatsioon, mis vahendab kogemusi ja uusi ideid elukeskkonnast huvitatud noorte hulgas

  8. Mitochondrial Ca2+ uptake in skeletal muscle health and disease

    CERN Document Server

    Zhou, Jingsong; Yi, Jianxun

    2016-01-01

    Muscle uses Ca2+ as a messenger to control contraction and relies on ATP to maintain the intracellular Ca2+ homeostasis. Mitochondria are the major sub-cellular organelle of ATP production. With a negative inner membrane potential, mitochondria take up Ca2+ from their surroundings, a process called mitochondrial Ca2+ uptake. Under physiological conditions, Ca2+ uptake into mitochondria promotes ATP production. Excessive uptake causes mitochondrial Ca2+ overload, which activates downstream adverse responses leading to cell dysfunction. Moreover, mitochondrial Ca2+ uptake could shape spatio-temporal patterns of intracellular Ca2+ signaling. Malfunction of mitochondrial Ca2+ uptake is implicated in muscle degeneration. Unlike non-excitable cells, mitochondria in muscle cells experience dramatic changes of intracellular Ca2+ levels. Besides the sudden elevation of Ca2+ level induced by action potentials, Ca2+ transients in muscle cells can be as short as a few milliseconds during a single twitch or as long as min...

  9. PIK3CA in colorectal cancer

    Directory of Open Access Journals (Sweden)

    Gieri eCathomas

    2014-03-01

    Full Text Available PIK3CA, the catalytic subunit of PI3K, is mutated in many different tumours, including colorectal cancer. Mutations of PIK3CA have been reported in 10 – 20% of colorectal cancer, about 80% of mutations found in two hot spots in exon 9 and exon 20. In RAS wild-type colorectal cancers, PIK3CA mutations have been associated with a worse clinical outcome and with a negative prediction of a response to targeted therapy by anti-EGFR monoclonal antibodies. However, these findings have not been confirmed in all studies and subsequent more detailed analysis has revealed that these effects may be restricted to mutations in Exon 20. Finally, mutations in PIK3CA may be the long sought biomarker for successful adjuvant therapy with aspirin in patients with colorectal cancer. Therefore, PIK3CA mutations appear to be a promising predictive biomarker; however, further data are needed to conclusively define the impact of somatic mutations in the PIK3CA gene for the management of patients with colorectal cancer.

  10. Tmem16A encodes the Ca2+-activated Cl- channel in mouse submandibular salivary gland acinar cells.

    Science.gov (United States)

    Romanenko, Victor G; Catalán, Marcelo A; Brown, David A; Putzier, Ilva; Hartzell, H Criss; Marmorstein, Alan D; Gonzalez-Begne, Mireya; Rock, Jason R; Harfe, Brian D; Melvin, James E

    2010-04-23

    Activation of an apical Ca(2+)-dependent Cl(-) channel (CaCC) is the rate-limiting step for fluid secretion in many exocrine tissues. Here, we compared the properties of native CaCC in mouse submandibular salivary gland acinar cells to the Ca(2+)-gated Cl(-) currents generated by Tmem16A and Best2, members from two distinct families of Ca(2+)-activated Cl(-) channels found in salivary glands. Heterologous expression of Tmem16A and Best2 transcripts in HEK293 cells produced Ca(2+)-activated Cl(-) currents with time and voltage dependence and inhibitor sensitivity that resembled the Ca(2+)-activated Cl(-) current found in native salivary acinar cells. Best2(-/-) and Tmem16A(-/-) mice were used to further characterize the role of these channels in the exocrine salivary gland. The amplitude and the biophysical footprint of the Ca(2+)-activated Cl(-) current in submandibular gland acinar cells from Best2-deficient mice were the same as in wild type cells. Consistent with this observation, the fluid secretion rate in Best2 null mice was comparable with that in wild type mice. In contrast, submandibular gland acinar cells from Tmem16A(-/-) mice lacked a Ca(2+)-activated Cl(-) current and a Ca(2+)-mobilizing agonist failed to stimulate Cl(-) efflux, requirements for fluid secretion. Furthermore, saliva secretion was abolished by the CaCC inhibitor niflumic acid in wild type and Best2(-/-) mice. Our results demonstrate that both Tmem16A and Best2 generate Ca(2+)-activated Cl(-) current in vitro with similar properties to those expressed in native cells, yet only Tmem16A appears to be a critical component of the acinar Ca(2+)-activated Cl(-) channel complex that is essential for saliva production by the submandibular gland.

  11. Ca(2+) handling in isolated brain mitochondria and cultured neurons derived from the YAC128 mouse model of Huntington's disease.

    Science.gov (United States)

    Pellman, Jessica J; Hamilton, James; Brustovetsky, Tatiana; Brustovetsky, Nickolay

    2015-08-01

    We investigated Ca(2+) handling in isolated brain synaptic and non-synaptic mitochondria and in cultured striatal neurons from the YAC128 mouse model of Huntington's disease. Both synaptic and non-synaptic mitochondria from 2- and 12-month-old YAC128 mice had larger Ca(2+) uptake capacity than mitochondria from YAC18 and wild-type FVB/NJ mice. Synaptic mitochondria from 12-month-old YAC128 mice had further augmented Ca(2+) capacity compared with mitochondria from 2-month-old YAC128 mice and age-matched YAC18 and FVB/NJ mice. This increase in Ca(2+) uptake capacity correlated with an increase in the amount of mutant huntingtin protein (mHtt) associated with mitochondria from 12-month-old YAC128 mice. We speculate that this may happen because of mHtt-mediated sequestration of free fatty acids thereby increasing resistance of mitochondria to Ca(2+)-induced damage. In experiments with striatal neurons from YAC128 and FVB/NJ mice, brief exposure to 25 or 100 μM glutamate produced transient elevations in cytosolic Ca(2+) followed by recovery to near resting levels. Following recovery of cytosolic Ca(2+), mitochondrial depolarization with FCCP produced comparable elevations in cytosolic Ca(2+), suggesting similar Ca(2+) release and, consequently, Ca(2+) loads in neuronal mitochondria from YAC128 and FVB/NJ mice. Together, our data argue against a detrimental effect of mHtt on Ca(2+) handling in brain mitochondria of YAC128 mice. We demonstrate that mutant huntingtin (mHtt) binds to brain synaptic and nonsynaptic mitochondria and the amount of mitochondria-bound mHtt correlates with increased mitochondrial Ca(2+) uptake capacity. We propose that this may happen due to mHtt-mediated sequestration of free fatty acids thereby increasing resistance of mitochondria to Ca(2+)-induced damage.

  12. Caldendrin, a neuron-specific modulator of Cav/1.2 (L-type) Ca2+ channels.

    Science.gov (United States)

    Tippens, Alyssa L; Lee, Amy

    2007-03-16

    EF-hand Ca2+-binding proteins such as calmodulin and CaBP1 have emerged as important regulatory subunits of voltage-gated Ca2+ channels. Here, we show that caldendrin, a variant of CaBP1 enriched in the brain, interacts with and distinctly modulates Cav1.2 (L-type) voltage-gated Ca2+ channels relative to other Ca2+-binding proteins. Caldendrin binds to the C-terminal IQ-domain of the pore-forming alpha1-subunit of Cav1.2 (alpha(1)1.2) and competitively displaces calmodulin and CaBP1 from this site. Compared with CaBP1, caldendrin causes a more modest suppression of Ca2+-dependent inactivation of Cav1.2 through a different subset of molecular determinants. Caldendrin does not bind to the N-terminal domain of alpha11.2, a site that is critical for functional interactions of the channel with CaBP1. Deletion of the N-terminal domain inhibits CaBP1, but spares caldendrin modulation of Cav1.2 inactivation. In contrast, mutations of the IQ-domain abolish physical and functional interactions of caldendrin and Cav1.2, but do not prevent channel modulation by CaBP1. Using antibodies specific for caldendrin and Cav1.2, we show that caldendrin coimmunoprecipitates with Cav1.2 from the brain and colocalizes with Cav1.2 in somatodendritic puncta of cortical neurons in culture. Our findings reveal functional diversity within related Ca2+-binding proteins, which may enhance the specificity of Ca2+ signaling by Cav1.2 channels in different cellular contexts.

  13. The in vivo performance of CaP/PLGA composites with varied PLGA microsphere sizes and inorganic compositions.

    Science.gov (United States)

    Hoekstra, Jan Willem M; Ma, Jinling; Plachokova, Adelina S; Bronkhorst, Ewald M; Bohner, Marc; Pan, Juli; Meijer, Gert J; Jansen, John A; van den Beucken, Jeroen J J P

    2013-07-01

    Enrichment of calcium phosphate (CaP) bone substitutes with poly(lactic-co-glycolic acid) (PLGA) microspheres to create porosity overcomes the problem of poor CaP degradation. The degradation of CaP-PLGA composites can be customized by changing the physical and chemical properties of PLGA and/or CaP. However, the effect of the size of dense (solid rather than hollow) PLGA microspheres in CaP has not previously been described. The present study aimed at determining the effect of different dense (i.e. solid) PLGA microsphere sizes (small (S) ~20μm vs. large (L) ~130μm) and of CaP composition (CaP with either anhydrous dicalcium phosphate (DCP) or calcium sulphate dihydrate (CSD)) on CaP scaffold biodegradability and subsequent bone in-growth. To this end mandibular defects in minipigs were filled with pre-set CaP-PLGA implants, with autologous bone being used as a control. After 4weeks the autologous bone group outperformed all CaP-PLGA groups in terms of the amount of bone present at the defect site. On the other hand, at 12weeks substantial bone formation was observed for all CaP-PLGA groups (ranging from 47±25% to 62±15%), showing equal amounts of bone compared with the autologous bone group (82±9%), except for CaP with DCP and large PLGA microspheres (47±25%). It was concluded that in the current study design the difference in PLGA microsphere size and CaP composition led to similar results with respect to scaffold degradation and subsequent bone in-growth. Further, after 12weeks all CaP-PLGA composites proved to be effective for bone substitution.

  14. Membrane-localized β-subunits alter the PIP2 regulation of high-voltage activated Ca2+ channels.

    Science.gov (United States)

    Suh, Byung-Chang; Kim, Dong-Il; Falkenburger, Björn H; Hille, Bertil

    2012-02-21

    The β-subunits of voltage-gated Ca(2+) (Ca(V)) channels regulate the functional expression and several biophysical properties of high-voltage-activated Ca(V) channels. We find that Ca(V) β-subunits also determine channel regulation by the membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PIP(2)). When Ca(V)1.3, -2.1, or -2.2 channels are cotransfected with the β3-subunit, a cytosolic protein, they can be inhibited by activating a voltage-sensitive lipid phosphatase to deplete PIP(2). When these channels are coexpressed with a β2a-subunit, a palmitoylated peripheral membrane protein, the inhibition is much smaller. PIP(2) sensitivity could be increased by disabling the two palmitoylation sites in the β2a-subunit. To further test effects of membrane targeting of Ca(V) β-subunits on PIP(2) regulation, the N terminus of Lyn was ligated onto the cytosolic β3-subunit to confer lipidation. This chimera, like the Ca(V) β2a-subunit, displayed plasma membrane localization, slowed the inactivation of Ca(V)2.2 channels, and increased the current density. In addition, the Lyn-β3 subunit significantly decreased Ca(V) channel inhibition by PIP(2) depletion. Evidently lipidation and membrane anchoring of Ca(V) β-subunits compete with the PIP(2) regulation of high-voltage-activated Ca(V) channels. Compared with expression with Ca(V) β3-subunits alone, inhibition of Ca(V)2.2 channels by PIP(2) depletion could be significantly attenuated when β2a was coexpressed with β3. Our data suggest that the Ca(V) currents in neurons would be regulated by membrane PIP(2) to a degree that depends on their endogenous β-subunit combinations.

  15. The incorporation site of Er in nanosized CaF 2

    CERN Document Server

    D'Acapito, Francesco; Blanc, Wilfried; Benabdesselam, Mourad; Mady, Franck; Gredin, Patrick; Mortier, Michel

    2016-01-01

    The incorporation site of Er dopants inserted at high and low concentration (respectively 5 and 0.5 mol %) in nanoparticles of CaF 2 is studied by X-ray Absorption Spectroscopy (XAS) at the Er L III edge. The experimental data are compared with the results of structural modeling based on Density Functional Theory (DFT). DFT-based molecular dynamics is also used to simulate complete theoretical EXAFS spectra of the model structures. The results is that Er substitutes for Ca in the structure and in the low concentration case the dopant ions are isolated. At high concentration the rare earth ions cluster together binding Ca vacancies.

  16. Comparative studies of the fishtail effect associated with surface pinning and oxygen vacancy network in spiral and layer-by-layer grown Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.L.; Ionescu, M.; Horvat, J.; Liao, X.Z.; Liu, H.K.; Dou, S.X. [Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, NSW (Australia)

    1998-10-01

    Magnetic hysteresis loops (M-H) between 5 and 50 K were measured on Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} (Bi-2212) crystals grown by the spiral or layer-by-layer growth mechanism using KCl flux and self-flux with a large temperature gradient growth technique. The spiral-grown crystals with a large density of spiral steps showed a strong fishtail effect with H{sub peak} at 1000-2000 Oe between 20 and 50 K, for both high-T{sub c} (86 K) and low-T{sub c} (76 K, oxygen underdoping) samples. For the layer-by-layer-grown crystals with an extremely smooth surface and annealed in oxygen-nitrogen, a weak fishtail effect with H{sub peak} at 300 Oe was observed between 20 and 40 K. The fishtail effect disappeared when the spirals were removed from the crystal surface, whereas the fishtail effect for the layer-by-layer-grown crystals was mainly controlled by oxygen content. The peak effect is fully reversible in the layer-by-layer-grown crystals by a proper annealing in oxygen and in nitrogen. From this comparison we conclude that the peak effect in Bi-2212 is caused by either surface pinning or oxygen vacancies for spiral- and layer-by-layer-grown crystals. Furthermore, the TEM study helps to show that the dislocation networks are not responsible for the fishtail effect. In the layer-by-layer-grown crystals, the presence of oxygen vacancies is a necessary but not a sufficient condition for the fishtail peak effect, but the networking of these vacancies may play a dominant role. (author)

  17. X-Ray Data on Extraterrestrial CA Dialuminate (CaAl4O7)

    Science.gov (United States)

    Weber, D.; Ross, C. R., II; Bischoff, A.

    1993-07-01

    After the first discovery of Ca-dialuminate (CaAl4O7) in Allende [1], in recent years this phase has been found in several carbonaceous chondrites. Ca- dialuminate is a major phase in Ca,Al-rich inclusions from ALH85085 (e.g., [2]) and a dominating phase in CAIs from Acfer 182 ([3,4]). X-ray data on Ca-dialuminate are known from synthetic (e.g., [5-8]; cell constants) and terrestrial CaAl4O7 ([9]; only d-spacings), but are not available from extraterrestrial Ca-dialuminate. We report here the results of the first X-ray study of extraterrestrial Ca- dialuminate. The data (Table 1) were obtained by microdiffraction using a Rigaku PSPC microdiffractometer at the Bayerisches Geoinstitut. Ni-filtered Cr radiation was used with a direct beam diameter of about 50 micrometers. This powder diffraction method allows in situ measurement of polycrystalline Ca- dialuminate in a thin section. The CaAl4O7-rich inclusion 022/9 described in [4], consisting of a ~200-micrometer-sized core of Ca-dialuminate surrounded by layers of melilite and Ca-pyroxene, was chosen for analysis. The polycrystalline core contains only a small number of tiny inclusions (especially perovskite) and is therefore an excellent candidate for an X-ray study. For determination of the d-spacings of Ca-dialuminate an external standard (Ag6Ge10P12) was used for detector calibration. A large number of reflections could be indexed based upon comparison with the X-ray pattern of synthetic CaAl4O7 available in the JCPDS compilation [7]. The comparison was simplified because of the high purity of CaAl4O7 in inclusion 022/9 [4], and suggests the same structure for synthetic and extraterrestrial Ca-dialuminate. For determination of lattice parameters (cell constants, cell volume) refinement calculations were made based on 14 reflections (Table 1). The data for extraterrestrial CaAl4O7 shown in Table 1 indicate a close similarity to those obtained for synthetic CaAl4O7. The cell constants a, b, and therefore the cell

  18. Ultrastructural and immunohistochemical localization of plasma membrane Ca2+-ATPase 4 in Ca2+-transporting epithelia

    DEFF Research Database (Denmark)

    Alexander, R Todd; Beggs, Megan R; Zamani, Reza

    2015-01-01

    Plasma Membrane Ca(2+)-ATPase's (PMCA) participate in epithelial Ca(2+) transport and intracellular Ca(2+) signaling. The Pmca4 isoform is enriched in distal nephron isolates and decreased in mice lacking the epithelial Ca(2+) channel, Trpv5. We therefore hypothesized that Pmca4 plays a significant...... in distal nephron cells at both the basolateral membrane and intracellular perinuclear compartments, but not submembranous vesicles, suggesting rapid trafficking to the plasma membrane is unlikely to occur in vivo. Pmca4 expression was not altered by perturbations in Ca(2+) balance, pointing...... detected Pmca1 in lateral membranes of enterocytes. In kidney, Pmca4 showed broad localization to the distal nephron. In mouse, expression was most abundant in segments coexpressing the epithelial Ca(2+) channel, Trpv5. Significant, albeit lower expression, was also evident in the region encompassing...

  19. Light-triggered cross-linking of alginates with caged Ca2+.

    Science.gov (United States)

    Cui, Jiaxi; Wang, Miao; Zheng, Yijun; Rodríguez Muñiz, Gemma Maria; del Campo, Aránzazu

    2013-05-13

    A strategy to light-trigger ionic cross-linking of alginates by incorporating a photosensitive Ca2+ cage (nitr-T) is presented. Upon irradiation, free Ca2+ was released, and this caused gelation of the alginate solution. Addition of Ca2+ "on-demand" allowed us to obtain homogeneous alginate (ALG) gels using concentrated initial ALG solutions (10%), not possible with other ionic gelation approaches. The cross-linking degree and derived mechanical properties of the hydrogel were modulated by the exposure dose. The light-mediated cross-linked alginate hydrogel displayed a significant improvement in the mechanical properties and homogeneity when compared to mixtures of alginate and soluble Ca2+ at comparable concentrations.

  20. Sarcolemmal Ca(2+)-entry through L-type Ca(2+) channels controls the profile of Ca(2+)-activated Cl(-) current in canine ventricular myocytes.

    Science.gov (United States)

    Horváth, Balázs; Váczi, Krisztina; Hegyi, Bence; Gönczi, Mónika; Dienes, Beatrix; Kistamás, Kornél; Bányász, Tamás; Magyar, János; Baczkó, István; Varró, András; Seprényi, György; Csernoch, László; Nánási, Péter P; Szentandrássy, Norbert

    2016-08-01

    Ca(2+)-activated Cl(-) current (ICl(Ca)) mediated by TMEM16A and/or Bestrophin-3 may contribute to cardiac arrhythmias. The true profile of ICl(Ca) during an actual ventricular action potential (AP), however, is poorly understood. We aimed to study the profile of ICl(Ca) systematically under physiological conditions (normal Ca(2+) cycling and AP voltage-clamp) as well as in conditions designed to change [Ca(2+)]i. The expression of TMEM16A and/or Bestrophin-3 in canine and human left ventricular myocytes was examined. The possible spatial distribution of these proteins and their co-localization with Cav1.2 was also studied. The profile of ICl(Ca), identified as a 9-anthracene carboxylic acid-sensitive current under AP voltage-clamp conditions, contained an early fast outward and a late inward component, overlapping early and terminal repolarizations, respectively. Both components were moderately reduced by ryanodine, while fully abolished by BAPTA, but not EGTA. [Ca(2+)]i was monitored using Fura-2-AM. Setting [Ca(2+)]i to the systolic level measured in the bulk cytoplasm (1.1μM) decreased ICl(Ca), while application of Bay K8644, isoproterenol, and faster stimulation rates increased the amplitude of ICl(Ca). Ca(2+)-entry through L-type Ca(2+) channels was essential for activation of ICl(Ca). TMEM16A and Bestrophin-3 showed strong co-localization with one another and also with Cav1.2 channels, when assessed using immunolabeling and confocal microscopy in both canine myocytes and human ventricular myocardium. Activation of ICl(Ca) in canine ventricular cells requires Ca(2+)-entry through neighboring L-type Ca(2+) channels and is only augmented by SR Ca(2+)-release. Substantial activation of ICl(Ca) requires high Ca(2+) concentration in the dyadic clefts which can be effectively buffered by BAPTA, but not EGTA.

  1. Comparative evaluations.

    Science.gov (United States)

    Bibace, Roger

    2008-03-01

    My response to Engelmann (2008) will be based on several questions that will allow both its author and the general reader to determine whether the assumptions I make as an interpreter of this complex paper are congruent or incongruent with their own interpretations of the text. The interpretations by the writer, by any commentator, and the diverse interpretations of a general audience together with my own interpretations will, I hope, facilitate some fruitful 'comparative evaluations.' I articulate my inferences of the most dense part of the paper, namely the 'concrete immediate Consciousness and the developing absent outside.' My hope is to address Engelmann's question: "Am I in a better disposition to judge modern theories of consciousness?" The last section of my response spells out more personal comments to my all too brief and single encounter with Arno Engelmann. It is there that Arno Engelmann's fascinating statement "I am a citizen of the world" is addressed through its counterparts in my life.

  2. Seventh Joint Meeting of K-J-CaP and CaPSURE: extending the global initiative to improve prostate cancer management.

    Science.gov (United States)

    Akaza, Hideyuki; Kim, Choung Soo; Carroll, Peter; Choi, In Young; Chung, Byung Ha; Cooperberg, Matthew R; Hirao, Yoshihiko; Hinotsu, Shiro; Horie, Shigeo; Lee, Ji Youl; Namiki, Mikio; Ng, Chi-Fai; Onozawa, Mizuki; Ozono, Seiichiro; Ueno, Satoru; Umbas, Rainy; Ye, Dingwei; Zhu, Gang

    2014-01-01

    This report summarizes the presentations and discussions that took place at the Seventh Joint Meeting of the Korea-Japan Study Group of Prostate Cancer (K-J-CaP) and the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) held in Seoul, Korea, in September 2013. The original J-CaP and CaPSURE Joint Initiative has now been established since 2007 and since the initial collaboration between research teams in the United States (US) and Japan, the project has expanded to include several other Asian countries. The objective of the initiative is to analyze and compare data for prostate cancer patients in the participating countries, looking at similarities and differences in patient management and outcomes. Until now the focus has been primarily on data generated within J-CaP and CaPSURE, both large-scale, longitudinal, observational databases of prostate cancer patients in Japan and the US, respectively. This year's meeting was hosted for the first time in Korea which has recently established its own national database-K-CaP-to add to the wealth of data generated by J-CaP and CaPSURE. As a newly-developed database, K-CaP has also provided a valuable 'template' for other countries, such as China and Indonesia, planning to establish their own national databases and this will ultimately allow greater opportunities for international data comparisons. A range of topics was discussed at this Seventh Joint Meeting including comparison of outcomes following androgen deprivation therapy or radical prostatectomy in patients with localized prostate cancer, the use of active surveillance as a treatment option and the triggers for intervention when employing this regimen, patient quality of life during treatment, the impact of comorbidities on outcomes, and a comparison of recent outcomes data between J-CaP and CaPSURE. The participants recognized that prostate cancer was now a global disease and therefore major insights into understanding and improving the

  3. Seventh Joint Meeting of K-J-CaP and CaPSURE: extending the global initiative to improve prostate cancer management

    Directory of Open Access Journals (Sweden)

    Hideyuki Akaza

    2014-06-01

    Full Text Available This report summarizes the presentations and discussions that took place at the Seventh Joint Meeting of the Korea–Japan Study Group of Prostate Cancer (K-J-CaP and the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE held in Seoul, Korea, in September 2013. The original J-CaP and CaPSURE Joint Initiative has now been established since 2007 and since the initial collaboration between research teams in the United States (US and Japan, the project has expanded to include several other Asian countries. The objective of the initiative is to analyze and compare data for prostate cancer patients in the participating countries, looking at similarities and differences in patient management and outcomes. Until now the focus has been primarily on data generated within J-CaP and CaPSURE, both large-scale, longitudinal, observational databases of prostate cancer patients in Japan and the US, respectively. This year's meeting was hosted for the first time in Korea which has recently established its own national database–K-CaP–to add to the wealth of data generated by J-CaP and CaPSURE. As a newly-developed database, K-CaP has also provided a valuable ‘template’ for other countries, such as China and Indonesia, planning to establish their own national databases and this will ultimately allow greater opportunities for international data comparisons. A range of topics was discussed at this Seventh Joint Meeting including comparison of outcomes following androgen deprivation therapy or radical prostatectomy in patients with localized prostate cancer, the use of active surveillance as a treatment option and the triggers for intervention when employing this regimen, patient quality of life during treatment, the impact of comorbidities on outcomes, and a comparison of recent outcomes data between J-CaP and CaPSURE. The participants recognized that prostate cancer was now a global disease and therefore major insights into understanding

  4. Endothelin-1 induces intracellular [Ca2+] increase via Ca2+ influx through the L-type Ca2+ channel, Ca2+-induced Ca2+ release and a pathway involving ETA receptors, PKC, PKA and AT1 receptors in cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    ZENG QingHua; LI XingTing; ZHONG GuoGan; ZHANG WenJie; SUN ChengWen

    2009-01-01

    Using fura-2-acetoxymethyl eater (AM) fluorescence imaging and patch clamp techniques, we found that endothelin-1 (ET-1) significantly elevated the intracellular calcium level ([Ca2+]1) in a dose-dependent manner and activated the L-type Ca2+ channel in cardiomyocytes isolated from rats.The effect of ET-1 on [Ca2+]1 elevation was abolished in the presence of the ETA receptor blocker BQ123,but was not affected by the ETa receptor blocker BQ788. ET-1-induced an increase in [Ca2+]1, which was inhibited 46.7% by pretreatment with a high concentration of ryanodine (10 μmol/L), a blocker of the ryanodine receptor. The ET-1-induced [Ca2+]i increase was also inhibited by the inhibltors of protein kinase A (PKA), protein kinase C (PKC) and angiotensin type 1 receptor (AT1 receptor). We found that ET-1 induced an enhancement of the amplitude of the whole cell L-type Ca2+ channel current and an Increase of open-state probability (NPo) of an L-type single Ca2+ channel. BQ123 completely blocked the ET-1-induced increase in calcium channel open-state probability. In this study we demonstrated that ET-1 regulates calcium overload through a series of mechanisms that include L-type Ca2+ channel activation and Ca2+-induced Ca2+ release (CICR). ETa receptors, PKC, PKA and AT1 receptors may also contribute to this pathway.

  5. Endothelin-1 induces intracellular [Ca2+] increase via Ca2+ influx through the L-type Ca2+ channel, Ca2+-induced Ca2+ release and a pathway involving ETA receptors, PKC, PKA and AT1 receptors in cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Using fura-2-acetoxymethyl ester (AM) fluorescence imaging and patch clamp techniques, we found that endothelin-1 (ET-1) significantly elevated the intracellular calcium level ([Ca2+]i) in a dose-dependent manner and activated the L-type Ca2+ channel in cardiomyocytes isolated from rats. The effect of ET-1 on [Ca2+]i elevation was abolished in the presence of the ETA receptor blocker BQ123, but was not affected by the ETB receptor blocker BQ788. ET-1-induced an increase in [Ca2+]i, which was inhibited 46.7% by pretreatment with a high concentration of ryanodine (10 μmol/L), a blocker of the ryanodine receptor. The ET-1-induced [Ca2+]i increase was also inhibited by the inhibitors of protein kinase A (PKA), protein kinase C (PKC) and angiotensin type 1 receptor (AT1 receptor). We found that ET-1 induced an enhancement of the amplitude of the whole cell L-type Ca2+ channel current and an increase of open-state probability (NPo) of an L-type single Ca2+ channel. BQ123 completely blocked the ET-1-induced increase in calcium channel open-state probability. In this study we demonstrated that ET-1 regulates calcium overload through a series of mechanisms that include L-type Ca2+ channel activation and Ca2+-induced Ca2+ release (CICR). ETA receptors, PKC, PKA and AT1 receptors may also contribute to this pathway.

  6. Ca2+ Channel Re-localization to Plasma-Membrane Microdomains Strengthens Activation of Ca2+-Dependent Nuclear Gene Expression

    Directory of Open Access Journals (Sweden)

    Krishna Samanta

    2015-07-01

    Full Text Available In polarized cells or cells with complex geometry, clustering of plasma-membrane (PM ion channels is an effective mechanism for eliciting spatially restricted signals. However, channel clustering is also seen in cells with relatively simple topology, suggesting it fulfills a more fundamental role in cell biology than simply orchestrating compartmentalized responses. Here, we have compared the ability of store-operated Ca2+ release-activated Ca2+ (CRAC channels confined to PM microdomains with a similar number of dispersed CRAC channels to activate transcription factors, which subsequently increase nuclear gene expression. For similar levels of channel activity, we find that channel confinement is considerably more effective in stimulating gene expression. Our results identify a long-range signaling advantage to the tight evolutionary conservation of channel clustering and reveal that CRAC channel aggregation increases the strength, fidelity, and reliability of the general process of excitation-transcription coupling.

  7. In vitro and in vivo evaluation of zinc-modified ca-si-based ceramic coating for bone implants.

    Science.gov (United States)

    Yu, Jiangming; Li, Kai; Zheng, Xuebin; He, Dannong; Ye, Xiaojian; Wang, Meiyan

    2013-01-01

    The host response to calcium silicate ceramic coatings is not always favorable because of their high dissolution rates, leading to high pH within the surrounding physiological environment. Recently, a zinc-incorporated calcium silicate-based ceramic Ca2ZnSi2O7 coating, developed on a Ti-6Al-4V substrate using plasma-spray technology, was found to exhibit improved chemical stability and biocompatibility. This study aimed to investigate and compare the in vitro response of osteoblastic MC3T3-E1 cells cultured on Ca2ZnSi2O7 coating, CaSiO3 coating, and uncoated Ti-6Al-4V titanium control at cellular and molecular level. Our results showed Ca2ZnSi2O7 coating enhanced MC3T3-E1 cell attachment, proliferation, and differentiation compared to CaSiO3 coating and control. In addition, Ca2ZnSi2O7 coating increased mRNA levels of osteoblast-related genes (alkaline phosphatase, procollagen α1(I), osteocalcin), insulin-like growth factor-I (IGF-I), and transforming growth factor-β1 (TGF-β1). The in vivo osteoconductive properties of Ca2ZnSi2O7 coating, compared to CaSiO3 coating and control, was investigated using a rabbit femur defect model. Histological and histomorphometrical analysis demonstrated new bone formation in direct contact with the Ca2ZnSi2O7 coating surface in absence of fibrous tissue and higher bone-implant contact rate (BIC) in the Ca2ZnSi2O7 coating group, indicating better biocompatibility and faster osseointegration than CaSiO3 coated and control implants. These results indicate Ca2ZnSi2O7 coated implants have applications in bone tissue regeneration, since they are biocompatible and able to osseointegrate with host bone.

  8. Ca(2+-dependent regulation of the Ca(2+ concentration in the myometrium mitochondria. II. Ca(2+ effects on mitochondria membranes polarization and [Ca(2+](m

    Directory of Open Access Journals (Sweden)

    L. G. Babich

    2017-06-01

    Full Text Available It is known that Ca2+ accumulation in the mitochondria undergoes complex regulation by Ca2+ itself. But the mechanisms of such regulation are still discussed. In this paper we have shown that Ca ions directly or indirectly regulate the level of myometrium mitochondria membranes polarization. The additions of 100 µM Ca2+ were accompanied by depolarization of the mitochondria membranes. The following experiments were designed to study the impact of Ca2+ on the myometrium mitochondria [Ca2+]m. Isolated myometrium mitochondria were preincubated without or with 10 μM Са2+ followed by 100 μM Са2+ addition. Experiments were conducted in three mediums: without ATP and Mg2+ (0-medium, in the presence of 3 mM Mg2+ (Mg-medium and 3 mM Mg2+ + 3 mM ATP (Mg,ATP-medium. It was shown that the effects of 10 μM Са2+ addition were different in different mediums, namely in 0- and Mg-medium the [Ca2+]m values increased, whereas in Mg,ATP-medium statistically reliable changes were not registered. Preincubation of mitochondria with 10 μM Са2+ did not affect the [Ca2+]m value after the addition of 100 μM Са2+. The [Ca2+]m values after 100 μM Са2+ addition were the same in 0- and Mg,ATP-mediums and somewhat lower in Mg-medium. Preliminary incubation of mitochondria with 10 μM Са2+ in 0- and Mg-mediums reduced changes of Fluo 4 normalized fluorescence values that were induced by 100 μM Са2+ additions, but in Mg,ATP-medium such differences were not recorded. It is concluded that Са2+ exchange in myometrium mitochondria is regulated by the concentration of Ca ions as in the external medium, so in the matrix of mitochondria. The medium composition had a significant impact on the [Са2+]m values in the absence of exogenous cation. It is suggested that light increase of [Са2+]m before the addition of 100 μM Са2+ may have a positive effect on the functional activity of the mitochondria.

  9. Physical conditions in CaFe interstellar clouds

    CERN Document Server

    Gnacinski, P

    2007-01-01

    Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. The chemical composition of CaFe clouds is that of the Solar System and no depletion of elements onto dust grains is seen. The CaFe clouds have high electron densities n=1 cm^-3 that leads to high column densities of neutral Ca and Fe.

  10. Physical conditions in CaFe interstellar clouds

    OpenAIRE

    Gnacinski, P.; Krogulec, M.

    2007-01-01

    Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. The chemical composition of CaFe clouds is that of the Solar System and no depletion of elements onto dust grains is seen. The CaFe clouds have high electron densities n=1 cm^-3 that leads to high column densities of neutral Ca and Fe.

  11. Mitochondrial calcium uniporter MCU supports cytoplasmic Ca2+ oscillations, store-operated Ca2+ entry and Ca2+-dependent gene expression in response to receptor stimulation.

    Directory of Open Access Journals (Sweden)

    Krishna Samanta

    Full Text Available Ca2+ flux into mitochondria is an important regulator of cytoplasmic Ca2+ signals, energy production and cell death pathways. Ca2+ uptake can occur through the recently discovered mitochondrial uniporter channel (MCU but whether the MCU is involved in shaping Ca2+ signals and downstream responses to physiological levels of receptor stimulation is unknown. Here, we show that modest stimulation of leukotriene receptors with the pro-inflammatory signal LTC4 evokes a series of cytoplasmic Ca2+ oscillations that are rapidly and faithfully propagated into mitochondrial matrix. Knockdown of MCU or mitochondrial depolarisation, to reduce the driving force for Ca2+ entry into the matrix, prevents the mitochondrial Ca2+ rise and accelerates run down of the oscillations. The loss of cytoplasmic Ca2+ oscillations appeared to be a consequence of enhanced Ca2+-dependent inactivation of InsP3 receptors, which arose from the loss of mitochondrial Ca2+ buffering. Ca2+ dependent gene expression in response to leukotriene receptor activation was suppressed following knockdown of the MCU. In addition to buffering Ca2+ release, mitochondria also sequestrated Ca2+ entry through store-operated Ca2+ channels and this too was prevented following loss of MCU. MCU is therefore an important regulator of physiological pulses of cytoplasmic Ca2+.

  12. Mitochondrial calcium uniporter MCU supports cytoplasmic Ca2+ oscillations, store-operated Ca2+ entry and Ca2+-dependent gene expression in response to receptor stimulation.

    Science.gov (United States)

    Samanta, Krishna; Douglas, Sophie; Parekh, Anant B

    2014-01-01

    Ca2+ flux into mitochondria is an important regulator of cytoplasmic Ca2+ signals, energy production and cell death pathways. Ca2+ uptake can occur through the recently discovered mitochondrial uniporter channel (MCU) but whether the MCU is involved in shaping Ca2+ signals and downstream responses to physiological levels of receptor stimulation is unknown. Here, we show that modest stimulation of leukotriene receptors with the pro-inflammatory signal LTC4 evokes a series of cytoplasmic Ca2+ oscillations that are rapidly and faithfully propagated into mitochondrial matrix. Knockdown of MCU or mitochondrial depolarisation, to reduce the driving force for Ca2+ entry into the matrix, prevents the mitochondrial Ca2+ rise and accelerates run down of the oscillations. The loss of cytoplasmic Ca2+ oscillations appeared to be a consequence of enhanced Ca2+-dependent inactivation of InsP3 receptors, which arose from the loss of mitochondrial Ca2+ buffering. Ca2+ dependent gene expression in response to leukotriene receptor activation was suppressed following knockdown of the MCU. In addition to buffering Ca2+ release, mitochondria also sequestrated Ca2+ entry through store-operated Ca2+ channels and this too was prevented following loss of MCU. MCU is therefore an important regulator of physiological pulses of cytoplasmic Ca2+.

  13. NMDA receptors on zebrafish Mauthner cells require CaMKII-α for normal development.

    Science.gov (United States)

    Roy, Birbickram; Ferdous, Jannatul; Ali, Declan W

    2015-02-01

    Calcium/calmodulin dependent protein kinase 2 (CaMKII) is a multifunctional protein that is highly enriched in the synapse. It plays important roles in neuronal functions such as synaptic plasticity, synaptogenesis, and neural development. Gene duplication in zebrafish has resulted in the occurrence of seven CaMKII genes (camk2a, camk2b1, camk2b2, camk2g1, camk2g2, camk2d1, and camk2d2) that are developmentally expressed. In this study, we used single cell, real-time quantitative PCR to investigate the expression of CaMKII genes in individual Mauthner cells (M-cells) of 2 days post fertilization (dpf) zebrafish embryos. We found that out of seven different CaMKII genes, only the mRNA for CaMKII-α was expressed in the M-cell at detectable levels, while all other isoforms were undetectable. Morpholino knockdown of CaMKII-α had no significant effect on AMPA synaptic currents (mEPSCs) but decreased the amplitude of NMDA mEPSCs. NMDA events exhibited a biexponential decay with τfast ≈ 30 ms and τslow ≈ 300 ms. Knockdown of CaMKII-α specifically reduced the amplitude of the slow component of the NMDA-mediated currents (mEPSCs), without affecting the fast component, the frequency, or the kinetics of the mEPSCs. Immunolabelling of the M-cell showed increased dendritic arborizations in the morphants compared with controls, and knockdown of CaMKII-α altered locomotor behaviors of touch responses. These results suggest that CaMKII-α is present in embryonic M-cells and that it plays a role in the normal development of excitatory synapses. Our findings pave the way for determining the function of specific CaMKII isoforms during the early stages of M-cell development.

  14. H+ countertransport and electrogenicity of the sarcoplasmic reticulum Ca2+ pump in reconstituted proteoliposomes.

    Science.gov (United States)

    Yu, X; Carroll, S; Rigaud, J L; Inesi, G

    1993-04-01

    The Ca2+ transport adenosine triphosphatase of sarcoplasmic reticulum was reconstituted in unilamellar liposomes prepared by reverse-phase evaporation. The size of the resulting proteoliposomes was similar to that of native sarcoplasmic reticulum vesicles, but their protein content was much lower, with a protein/lipid ratio (wt/wt) of 1:40-160, as compared with 1:1 in the native membrane. The proteoliposomes sustained adenosine triphosphate-dependent Ca2+ uptake at rates proportional to the protein content (1-2 mumol Ca2+/mg protein/min), reaching asymptotic levels corresponding to a lumenal calcium concentration of 10-20 mM. The low permeability of the proteoliposomes permitted direct demonstration of Ca2+/H+ countertransport and electrogenicity by parallel measurements in the same experimental system. Countertransport of one H+ per one Ca2+ was demonstrated, and inhibition of the Ca2+ pump by lumenal alkalinization was relieved by the H+ ionophore carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone. Consistent with the countertransport stoichiometry, net positive charge displacement was produced by Ca2+ transport, as revealed by a rapid oxonol VI absorption rise. The initial rise and the following steady-state level of oxonol absorption were highest when SO4(2-) was the prevalent anion and lowest in the presence of the lipophilic anion SCN-. The influence of anions was attributed to potential driven counterion compensation. The absorption rise was rapidly collapsed by addition of valinomycin in the presence of K+. Experimentation with Ca2+ and H+ ionophores was consistent with a primary role of Ca2+ and H+ in net charge displacement. The estimated value of the steady-state electrical potential observed under optimal conditions was approximately 50 mV and was accounted for by the estimated charge transfer associated with Ca2+ and H+ countertransport under the same conditions.

  15. αCaMKII autophosphorylation controls the establishment of alcohol drinking behavior.

    Science.gov (United States)

    Easton, Alanna C; Lucchesi, Walter; Lourdusamy, Anbarasu; Lenz, Bernd; Solati, Jalal; Golub, Yulia; Lewczuk, Piotr; Fernandes, Cathy; Desrivieres, Sylvane; Dawirs, Ralph R; Moll, Gunther H; Kornhuber, Johannes; Frank, Josef; Hoffmann, Per; Soyka, Michael; Kiefer, Falk; Schumann, Gunter; Peter Giese, K; Müller, Christian P; Treutlein, Jens; Cichon, Sven; Ridinger, Monika; Mattheisen, Peter; Herms, Stefan; Wodarz, Norbert; Zill, Peter; Maier, Wolfgang; Mössner, Rainald; Gaebel, Wolfgang; Dahmen, Norbert; Scherbaum, Norbert; Schmäl, Christine; Steffens, Michael; Lucae, Susanne; Ising, Marcus; Müller-Myhsok, Bertram; Nöthen, Markus M; Mann, Karl; Rietschel, Marcella

    2013-08-01

    The α-Ca(2+)/calmodulin-dependent protein kinase II (αCaMKII) is a crucial enzyme controlling plasticity in the brain. The autophosphorylation of αCaMKII works as a 'molecular memory' for a transient calcium activation, thereby accelerating learning. We investigated the role of αCaMKII autophosphorylation in the establishment of alcohol drinking as an addiction-related behavior in mice. We found that alcohol drinking was initially diminished in αCaMKII autophosphorylation-deficient αCaMKII(T286A) mice, but could be established at wild-type level after repeated withdrawals. The locomotor activating effects of a low-dose alcohol (2 g/kg) were absent in αCaMKII(T286A) mice, whereas the sedating effects of high-dose (3.5 g/kg) were preserved after acute and subchronic administration. The in vivo microdialysis revealed that αCaMKII(T286A) mice showed no dopamine (DA) response in the nucleus accumbens to acute or subchronic alcohol administration, but enhanced serotonin (5-HT) responses in the prefrontal cortex. The attenuated DA response in αCaMKII(T286A) mice was in line with altered c-Fos activation in the ventral tegmental area after acute and subchronic alcohol administration. In order to compare findings in mice with the human condition, we tested 23 single-nucleotide polymorphisms (SNPs) in the CAMK2A gene for their association with alcohol dependence in a population of 1333 male patients with severe alcohol dependence and 939 controls. We found seven significant associations between CAMK2A SNPs and alcohol dependence, one of which in an autophosphorylation-related area of the gene. Together, our data suggest αCaMKII autophosphorylation as a facilitating mechanism in the establishment of alcohol drinking behavior with changing the DA-5-HT balance as a putative mechanism.

  16. Relationship Between Ca2+-CaM and Ethylene-Induced PG Activity in Tomato Fruit

    Institute of Scientific and Technical Information of China (English)

    GU Cai-qin; XI Yu-fang; GUAN Jun-feng; LI Guang-min

    2003-01-01

    Polygalacturonase (PG) was studied during ripening and senescence of postharvest tomatofruit at pink stage at low and normal temperature. The results showed that the PG activity increased, thendecreased during ripening and senescence of tomato. Low temperature inhibited but ethylene enhanced PGactivity. Ethylene also enhanced caimodulin content, which was dependent on Ca2+ concentration in cell.When EGTA(Ca2+ chelator), verapamil (Vp) and LaCl3 (Ca2+ channel blockers), trifluoperazine and chloro-promaize (two CaM antagonisms) were used to treat tomato fruit at green mature stage with ethylene, theycould reverse ethylene-induced increase in PG activity, but Vp, chloropromaize (CPZ), trifluoperazine(TFP) could not directly influence PG activity, which indirectly indicated that influx of Ca2+ from the ex-tracellular space including the cell wall via the Ca2+ channel localized in plasma membrane and CaM were re-quired for ethylene-induced PG activity increase and that ethylene signal transduction may be related to Ca2+- CaM messenger system.

  17. Negative feedback from CaSR signaling to aquaporin-2 sensitizes vasopressin to extracellular Ca2.

    Science.gov (United States)

    Ranieri, Marianna; Tamma, Grazia; Di Mise, Annarita; Russo, Annamaria; Centrone, Mariangela; Svelto, Maria; Calamita, Giuseppe; Valenti, Giovanna

    2015-07-01

    We previously described that high luminal Ca(2+) in the renal collecting duct attenuates short-term vasopressin-induced aquaporin-2 (AQP2) trafficking through activation of the Ca(2+)-sensing receptor (CaSR). Here, we evaluated AQP2 phosphorylation and permeability, in both renal HEK-293 cells and in the dissected inner medullary collecting duct, in response to specific activation of CaSR with NPS-R568. In CaSR-transfected cells, CaSR activation drastically reduced the basal levels of AQP2 phosphorylation at S256 (AQP2-pS256), thus having an opposite effect to vasopressin action. When forskolin stimulation was performed in the presence of NPS-R568, the increase in AQP2-pS256 and in the osmotic water permeability were prevented. In the freshly isolated inner mouse medullar collecting duct, stimulation with forskolin in the presence of NPS-R568 prevented the increase in AQP2-pS256 and osmotic water permeability. Our data demonstrate that the activation of CaSR in the collecting duct prevents the cAMP-dependent increase in AQP2-pS256 and water permeability, counteracting the short-term vasopressin response. By extension, our results suggest the attractive concept that CaSR expressed in distinct nephron segments exerts a negative feedback on hormones acting through cAMP, conferring high sensitivity of hormone to extracellular Ca(2+). © 2015. Published by The Company of Biologists Ltd.

  18. Heat and hyposmotic stimulation increase in [Ca2+]i by Ca2+ influx in rat synoviocytes

    Institute of Scientific and Technical Information of China (English)

    SUN WenWu; HU Fen; YANG WenXiu

    2008-01-01

    Rheumatoid arthritis (RA), which is marked by inflammatory synovitis, is a common, chronic autoimmune-disease, whose pathogenesis is complex and still unclear. In order to explore the effects of heat and hyposmotic stimuli on synoviocytes in rheumatoid arthritis, the changes of [Ca2+]i induced by heat, hyposmotic and 4α-PDD stimuli were observed in synoviocytes. [Ca2+]i elevation induced by heat ≥ 28℃, hyposmotic and 4α-PDD stimuli is found to be positively relative to increasing temperature, decreasing osmolality and rising concentration of 4α-PDD. Results show that there is reciprocity among these stimuli and desensitization, and that [Ca2+]i elevation depends on Ca2+ influx, but not necessarily links to Ca2+ release from intracellular stores and voltage-dependent Ca2+ channel in synoviocytes. The above characteristics of Ca2+ influx are similar to those of TRPV4. A probable mechanism has been suggested that heat and hyposmotic stimulation might increase the level of [Ca2+]i by activating the TRPV4-like channel and Ca2+ influx in the synoviocytes.

  19. Quicklime (CaO) Stabilization of fine-grained marine sediments in low temperature areas

    DEFF Research Database (Denmark)

    Skels, Peteris; Ingeman-Nielsen, Thomas; Jørgensen, Anders Stuhr;

    2011-01-01

    in a soil-CaO mixture was determined using a number of laboratory methods, such as pH test, consistency limit analysis, degree of compaction, and short term California Bearing Ratio (CBR) values. The study also numerically demonstrates a long term strength development of the soil-CaO mixture at 1°C and 10°C...... curing temperatures, comparing stabilization effectiveness between low and normal soil temperature conditions....

  20. Dynamical Effects on Sub-barrier Fusion of 40,48Ca+90,96Zr

    Institute of Scientific and Technical Information of China (English)

    ZHANG Huan-Qiao; WANG Ning; LIU Zu-Huan; YANG Feng; LIN Cheng-Jian; RUAN Ming; WU Yue-Wei; LI Zhu-Xia; WU Xi-Zhen; ZHAO Kai

    2005-01-01

    @@ We have measured the fusion cross sections for 48Ca+90,96Zr around the Coulomb barrier and presented them along with the experimental data of 40Ca+90,96Zr. The experimental results are compared with the improved quantum molecular dynamics model calculations. It is shown in comparison that the dynamical effects play an important role in the sub-barrier fusion reactions.

  1. Nonlinear optical properties of polymer dispersed liquid crystals doped with La2CaB10019

    Science.gov (United States)

    Zegadlo, Krzysztof B.; El Ouazzani, Hasnaa; Cieslik, Iwona; Weglowski, Rafal; Zmija, Jozef; Klosowicz, Stanislaw; Majchrowski, Andrzej; Mysliwiec, Jaroslaw; Sahraoui, Bouchta; Karpierz, Miroslaw A.

    2012-08-01

    Second order nonlinearity in polymer dispersed liquid crystal structures containing La2CaB10O19 nanocrystals were measured with use of the Maker fringes method. The composites with different concentration of La2CaB10O19 crystallites or without them were compared. It was shown that there is a strong influence of the crystals concentration on the second harmonic generation in such structures which can be additionally modified by external electric field.

  2. CaCl2-CaO熔盐中金属钙的电沉积行为研究

    Institute of Scientific and Technical Information of China (English)

    郭君康

    2014-01-01

    在900℃下,采用循环伏安法对CaCl2-CaO熔盐中金属钙的电沉积行为进行了研究.研究结果表明,在CaCl2熔盐中加入CaO后,熔盐中Ca2+的还原电位正移,且Ca2+的还原过程受扩散控制.

  3. The vascular Ca2+-sensing receptor regulates blood vessel tone and blood pressure.

    Science.gov (United States)

    Schepelmann, M; Yarova, P L; Lopez-Fernandez, I; Davies, T S; Brennan, S C; Edwards, P J; Aggarwal, A; Graça, J; Rietdorf, K; Matchkov, V; Fenton, R A; Chang, W; Krssak, M; Stewart, A; Broadley, K J; Ward, D T; Price, S A; Edwards, D H; Kemp, P J; Riccardi, D

    2016-02-01

    The extracellular calcium-sensing receptor CaSR is expressed in blood vessels where its role is not completely understood. In this study, we tested the hypothesis that the CaSR expressed in vascular smooth muscle cells (VSMC) is directly involved in regulation of blood pressure and blood vessel tone. Mice with targeted CaSR gene ablation from vascular smooth muscle cells (VSMC) were generated by breeding exon 7 LoxP-CaSR mice with animals in which Cre recombinase is driven by a SM22α promoter (SM22α-Cre). Wire myography performed on Cre-negative [wild-type (WT)] and Cre-positive (SM22α)CaSR(Δflox/Δflox) [knockout (KO)] mice showed an endothelium-independent reduction in aorta and mesenteric artery contractility of KO compared with WT mice in response to KCl and to phenylephrine. Increasing extracellular calcium ion (Ca(2+)) concentrations (1-5 mM) evoked contraction in WT but only relaxation in KO aortas. Accordingly, diastolic and mean arterial blood pressures of KO animals were significantly reduced compared with WT, as measured by both tail cuff and radiotelemetry. This hypotension was mostly pronounced during the animals' active phase and was not rescued by either nitric oxide-synthase inhibition with nitro-l-arginine methyl ester or by a high-salt-supplemented diet. KO animals also exhibited cardiac remodeling, bradycardia, and reduced spontaneous activity in isolated hearts and cardiomyocyte-like cells. Our findings demonstrate a role for CaSR in the cardiovascular system and suggest that physiologically relevant changes in extracellular Ca(2+) concentrations could contribute to setting blood vessel tone levels and heart rate by directly acting on the cardiovascular CaSR.

  4. Upregulation of Na+ and Ca2+ transporters in arterial smooth muscle from ouabain-induced hypertensive rats

    OpenAIRE

    Pulina, Maria V.; Zulian, Alessandra; Berra-Romani, Roberto; Beskina, Olga; Mazzocco-Spezzia, Amparo; Baryshnikov, Sergey G.; Papparella, Italia; Hamlyn, John M.; Blaustein, Mordecai P.; Golovina, Vera A.

    2009-01-01

    Prolonged ouabain administration (25 μg·kg−1·day−1 for 5 wk) induces “ouabain hypertension” (OH) in rats, but the molecular mechanisms by which ouabain elevates blood pressure are unknown. Here, we compared Ca2+ signaling in mesenteric artery smooth muscle cells (ASMCs) from normotensive (NT) and OH rats. Resting cytosolic free Ca2+ concentration ([Ca2+]cyt; measured with fura-2) and phenylephrine-induced Ca2+ transients were augmented in freshly dissociated OH ASMCs. Immunoblots revealed tha...

  5. Osteogenesis around CaP-coated titanium implants visualized using 3D histology and micro-computed tomography

    NARCIS (Netherlands)

    Cuijpers, V.M.J.I.; Alghamdi, H.S.; Dijk, N.W.M. van; Jaroszewicz, J.; Walboomers, X.F.; Jansen, J.A.

    2015-01-01

    Calcium phosphate (CaP) coatings can enhance the performance of bone implants in compromised conditions, such as osteoporosis. Therefore, this study compared non-coated vs. CaP-coated (n = 8) titanium implants in osteoporotic ovariectomized (OVX) rats. Bone volume (BV) was assessed using micro-compu

  6. Difference in the distributions between Ca content and the degree of oxidative damage in human hair determined by x-ray imaging

    Science.gov (United States)

    Ito, A.; Inoue, T.; Kawai, T.; Taki, Y.; Inoue, S.; Shimizu, T.; Shinohara, K.

    2016-01-01

    In order to examine the cause of Ca distribution in human hair, the distributions of Ca and oxidation of cystine, a major sulfur-containing amino acid in hair, were compared in submicron resolution with X-ray spectromicroscopy at the Ca-K and S-K absorption edges. Ca distribution was also detected with high sensitivity by X-ray Fluorescence Analysis (XRF) in a few micron resolution. Hair samples were treated with bleach followed by Ca soaking. The increase of Ca content was in parallel with the progression of the oxidation by bleach treatment, beginning from the cuticle, the outer region of the hair. This increase was dependent on the concentration of bleach solution and treatment time. On the other hand Ca content in medulla, the central region of the hair, was apparent even in hair with no bleach treatment, and seemed to be little influenced by the Ca soaking following bleach treatment.

  7. Functional expression of Na-Ca exchanger clones measured with the fluorescent Ca(2+)-indicating dye fluo-3.

    Science.gov (United States)

    Schnetkamp, P P

    1996-01-01

    The process of Ca2+ homeostasis is of prime importance to all cells because of the ubiquitous role of cytoplasmic Ca2+ as an intracellular messenger and the cytotoxicity of sustained elevated cytosolic Ca2+ concentrations. Two classes of plasma membrane proteins are responsible for maintaining cytosolic free Ca2+ in the submicromolar range against a very large electrochemical Ca2+ gradient across the plasma membrane, the ATP-driven Ca2+ pump and Na-Ca exchangers. Two types of Na-Ca exchangers are known, the 3Na:1Ca exchangers found in heart, brain, kidney, and most other tissues and the 4Na:1Ca+ 1K exchanger found in retinal rod and cone photoreceptors. Functional expression of Na-Ca(/K) exchangers is most often measured as 45Ca uptake in Na(+)-loaded cells or as Na-Ca exchange currents with the giant excised patch technique. In this study, two functional assays used to detect expression of the bovine heart Na-Ca exchanger in CHO cells are described. Both assays are based on measurements of cytosolic free Ca2+ with the fluorescent Ca(2+)-indicating dye fluo-3 and should be equally applicable in the study of functional expression of both Na-Ca and Na-Ca/K exchanger clones.

  8. CaMKII inhibition targeted to the sarcoplasmic reticulum inhibits frequency dependent acceleration of relaxation and Ca2+ current facilitation

    OpenAIRE

    Picht, Eckard; DeSantiago, Jaime; Huke, Sabine; Kaetzel, Marcia A.; Dedman, John R.; Bers, Donald M.

    2006-01-01

    Cardiac Ca2+/calmodulin-dependent protein kinase II (CaMKII) in heart has been implicated in Ca2+ current (ICa) facilitation, enhanced sarcoplasmic reticulum (SR) Ca2+ release and frequency dependent acceleration of relaxation (FDAR) via enhanced SR Ca2+ uptake. However, questions remain about how CaMKII may work in these three processes. Here we tested the role of CaM-KII in these processes using transgenic mice (SR-AIP) that express four concatenated repeats of the CaMKII inhibitory peptide...

  9. CaSO4氧载体煤基合成气化学链燃烧模拟研究%Simulated investigation of chemical looping combustion with coal-derived syngas and CaSO4 oxygen carrier

    Institute of Scientific and Technical Information of China (English)

    王保文; 晏蓉; 郑瑛; 赵海波; 郑楚光

    2011-01-01

    Compared to metal oxides, CaSO4 adopted as oxygen carrier (OC) in chemical looping combustion (CLC) presents several advantages such as low cost, easy availability and superior oxygen transfer capacity, whilst the SO2 emission and solid sulfur deposit in the process could be a big concern. In this study, thermodynamic simulations were conducted to investigate the sulfur distribution in a CLC system with CaSO4 as OC and syngas derived from coal as the fuel. Several findings were attained: (i) On the main products and reaction pathways in the fuel reactor (FR), at the low temperature of 100 ℃ ~400 ℃, the main sulfur species and carbon deposit were H2S and CaCO3 via the methanation of CO with H2 coupled with the shift reaction of CO with H2O(g) and the ensuing thermochemical sulfate reduction (TSR). Then at 400 ℃ ~915 ℃, CaS and CO2 were the main products through the reaction of CaSO4 with H2 or CO, and both products increased with increasing FR temperature. Furthermore, at the FR temperature higher than 915 ℃, due to the initiation of the solid side reaction between CaS and CaSO4, the percentage of CaS declined. In contrary, the percentages of CaO, H2 and CO increased possibly due to the consumption of part of CaSO4 in the side reaction and thus not enough lattice oxygen available. In the air reactor( AR), the oxidization of CaS by air into CaSO4 was always dominant. Besides at ΦAR below 0.8, both the solid side reaction of CaSO4 with CaS and the oxidization of CaS into CaO were simultaneously in effect. (ii) In the FR, the optimized condition was suggested as at around 915 ℃, atmospheric condition and carefully controlled ΦFR around unity. (iii) In the AR, sufficient supply of air was important for the oxidization of CaS, and ΦAR ≥ 1 would ensure the full oxidization of CaS into CaSO4 and prevent the emission of SO2 and formation of CaO as well. Overall, this study provided the most suitable conditions of using CaSO4 as OC in CLC of syngas with

  10. Compound effect of CaCO{sub 3} and CaSO{sub 4}·2H{sub 2}O on the strength of steel slag: cement binding materials

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Liqian; Liu, Jiaxiang; Liu, Qian, E-mail: ljxpost@263.net [Beijing Key Laboratory of Electrochemical Process and Technology for Materials, The State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing (China)

    2016-03-15

    In this study, we replaced 30% of the cement with steel slag to prepare binding material; additionally, small amounts of CaCO{sub 3} and CaSO{sub 4}·2H{sub 2}O were added. This was done to study the compound effect of CaCO{sub 3} and CaSO{sub 4}·2H{sub 2}O on the strength of steel slag-cement binding materials. The hydration degree of the steel slag cementitious material was analyzed by XRD, TG and SEM. The results showed that the optimum proportions of CaCO{sub 3} and CaSO{sub 4}·2H{sub 2}O were 3% and 2%, respectively. Compared with the steel slag-cement binders without adding CaCO{sub 3} and CaSO{sub 4}·2H{sub 2}O, the compressive strength increased by 59.9% at 3 days and by 17.8% at 28 days. Acting as the nucleation matrix, CaCO{sub 3} could accelerate the hydration of C{sub 3}S. In addition, CaCO{sub 3} was involved in the hydration reaction, generating a new hydration product, which could stably exist in a slurry. Meanwhile, CaSO{sub 4}·2H{sub 2}O could increase the number of AFt. The compound effect of CaCO{sub 3} and CaSO{sub 4}·2H{sub 2}O enhanced the intensity of steel slag-cement binding materials and improved the whole hydration behavior. (author)

  11. Formation process of micro arc oxidation coatings obtained in a sodium phytate containing solution with and without CaCO{sub 3} on binary Mg-1.0Ca alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, R.F. [School of Material and Electromechanics, Jiangxi Science and Technology Normal University, Nanchang 330013 (China); Zhang, Y.Q. [Zhejiang DunAn Light Alloy Technology CO,.LTD, Zhuji 311835 (China); Hunan University of Science and Technology, Xiangtan 411201 (China); Zhang, S.F.; Qu, B. [School of Material and Electromechanics, Jiangxi Science and Technology Normal University, Nanchang 330013 (China); Guo, S.B. [Hunan University of Science and Technology, Xiangtan 411201 (China); Xiang, J.H., E-mail: xiangjunhuai@163.com [School of Material and Electromechanics, Jiangxi Science and Technology Normal University, Nanchang 330013 (China)

    2015-01-15

    Highlights: • Compared to the Mg phase, the area of Mg{sub 2}Ca phase is much smaller. • The coatings are preferentially developed on the area adjacent to Mg{sub 2}Ca phase. • During MAO process, some sodium phytate molecules are hydrolyzed. • Anodic coatings are developed from uneven to uniform. - Abstract: Micro arc oxidation (MAO) is an effective method to improve the corrosion resistance of magnesium alloys. In order to reveal the influence of alloying element Ca and CaCO{sub 3} electrolyte on the formation process and chemical compositions of MAO coatings on binary Mg-1.0Ca alloy, anodic coatings after different anodizing times were prepared on binary Mg-1.0Ca alloy in a base solution containing 3 g/L sodium hydroxide and 15 g/L sodium phytate with and without addition of CaCO{sub 3}. The coating formation was studied by using scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results show that Mg-1.0Ca alloy is composed of two phases, the Mg phase and Mg{sub 2}Ca phase. After treating for 5 s, the coating began to develop and was preferentially formed on the area nearby Mg{sub 2}Ca phase, which may be resulted from the intrinsic electronegative potential of the Mg phase than that of Mg{sub 2}Ca phase. Anodic coatings unevenly covered the total surface after 20 s. After 80 s, the coatings were uniformly developed on Mg-1.0Ca alloy with micro pores. During MAO process, some sodium phytate molecules are hydrolyzed into inorganic phosphate. CaCO{sub 3} has minor influence on the calcium content of the obtained MAO coatings.

  12. Laser cooling and slowing of CaF molecules

    Science.gov (United States)

    Truppe, Stefan; Williams, Hannah; Hambach, Moritz; Sauer, Ben; Hinds, Ed; Tarbutt, Mike

    2016-05-01

    We have developed a cold and bright source for CaF molecules and use laser radiation pressure to slow the molecules to within the capture velocity of a magneto-optical trap (MOT). Using laser ablation of Ca into a continuous flow of cryogenic Helium buffer gas mixed with SF6 we produce up to 1011 molecules per steradian per pulse in a single rotational state. The molecules move with a mean forward velocity of 160m/s and have a velocity spread of 80m/s. We then apply laser radiation pressure to the molecular beam to slow and cool the molecules. We form a quasi-closed laser-cooling cycle by using a main cooling laser to drive the B2Σ+ (v' = 0) - X2Σ+ (v'' = 0) transition and a single repump laser to address the A2Π1 / 2 (v' = 0) -X2Σ+ (v'' = 1) transition. Radio-frequency sidebands applied to both lasers address the hyperfine structure. By chirping the frequencies of both lasers to keep the decelerating molecules resonant with the light, we scatter more than 10000 photons and reduce the speed to below 50 m/s. We achieve a similar effect by broadening the linewidth of the laser to several hundred MHz. This ``white-light'' slowing is compared to the chirped slowing technique. We also present progress towards a MOT of CaF molecules.

  13. Searching for circumplanetary disks around LkCa 15

    CERN Document Server

    Isella, Andrea; Carpenter, John M; Pe'rez, Laura M; Ricci, Luca

    2014-01-01

    We present Karl G. Jansky Very Large Array (VLA) observations of the 7 mm continuum emission from the disk surrounding the young star LkCa 15. The observations achieve an angular resolution of 70 mas and spatially resolve the circumstellar emission on a spatial scale of 9 AU. The continuum emission traces a dusty annulus of 45 AU in radius that is consistent with the dust morphology observed at shorter wavelengths. The VLA observations also reveal a compact source at the center of the disk, possibly due to thermal emission from hot dust or ionized gas located within a few AU from the central star. No emission is observed between the star and the dusty ring, and, in particular, at the position of the candidate protoplanet LkCa 15 b. By comparing the observations with theoretical models for circumplanetary disk emission, we find that if LkCa~15~b is a massive planet (>5 M_J) accreting at a rate greater than 1.e-6 M_J yr^{-1}, then its circumplanetary disk is less massive than 0.1 M_J, or smaller than 0.4 Hill r...

  14. Role and mechanism of subcellular Ca2+ distribution in the action of two inotropic agents with different toxicity.

    Science.gov (United States)

    Alemanni, Matteo; Rocchetti, Marcella; Re, Daniele; Zaza, Antonio

    2011-05-01

    Pro-arrhythmic risk strongly limits the therapeutic value of current inotropic interventions. Istaroxime (previously PST2744) is a novel inotropic agent, significantly less pro-arrhythmic than digoxin that, in addition to block Na(+)/K(+) pump, stimulates sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA2). Here we compare istaroxime and digoxin effects to further address the role of SR modulation in reducing the toxicity associated with Na(+)/K(+) pump blockade. In murine ventricular myocytes both compounds increased cell twitch (inotropy) in a concentration-dependent fashion. At high concentrations digoxin, but not istaroxime, induced unstimulated contractions, a sign of pro-arrhythmic toxicity. To evaluate the mechanism of this difference, we compared the two drugs at concentrations exerting equal inotropy but different toxicity. At these concentrations: (1) the two drugs equally inhibited the Na(+)/K(+) pump; (2) digoxin induced larger increases in resting Ca(2+) and in diastolic Ca(2+) during pacing; (3) neither drug affected the relationship between RyR-mediated SR Ca(2+) leak and Ca(2+) content; (4) istaroxime, but not digoxin, enhanced SR Ca(2+) reuptake rate. In conclusion, digoxin toxicity was associated to larger accumulation of cytosolic Ca(2+), which did not result from RyR facilitation, but which might ultimately induce it to promote unstimulated Ca(2+) release. The lower toxicity of Na(+)/K(+) pump blockade by istaroxime may thus reflect improved Ca(2+) confinement within the SR, likely to result from concomitant SERCA2 stimulation.

  15. Effect of Ca2+/CaM Messenger on Drought Resistance of Phyllostachys edulis%Ca2+/CaM信使对毛竹抗旱生理的影响

    Institute of Scientific and Technical Information of China (English)

    姜琴; 应叶青; 解楠楠; 方伟

    2012-01-01

    The effect of calcium messenger on main drought resistance physiological indexes of Phyl-lostachys edulis was studied by investigating the activities of antioxidant enzymes, the content of praline, MDA, hydrogen peroxide and soluble protein in Phyllostachys edulis under water stress, after being blocked calcium messenger transduction by EGTA,LaCl3 and heparin,CPZ and CaCl2. Compared with the control,CaCl2 treatment increased SOD, POD and CAT enzyme activity, and soluble protein content, decreased MDA, proline and hydrogen peroxide content. Compared with the control, EGTA, LaCl3 and heparin, and CPZ could increase the hydrogen peroxide content, decrease SOD and CAT enzyme activity, and proline and soluble protein content. However, LaCl3 and heparin led to little changes of MDA content; heparin and CPZ had no obviously effect on POD enzyme activity. The results suggested that Ca2 + /CaM messenger might control drought resistance of Phyllostachys edulis by affecting activities of antioxidant enzymes and contents of proline and soluble protein through different transduction paths to affect them.%为了探讨钙信号对毛竹抗旱生理指标的影响,在水分胁迫下用EGTA、LaCl3、heparin、CPZ和CaCl2处理毛竹幼苗后,研究干旱胁迫下毛竹叶片内保护酶活性、脯氨酸、丙二醛、过氧化氢和可溶性蛋白的变化.结果表明:与对照相比,CaCl2处理明显提高了毛竹叶片保护酶活性和可溶性蛋白含量,降低了MDA、脯氨酸和过氧化氢含量;EGTA、LaCl3 、heparin和CPZ处理提高了毛竹过氧化氢含量,抑制了SOD和CAT活性的上升,破坏了脯氨酸和可溶性蛋白的积累.但LaCl3和heparin处理对MDA含量的影响不大,heparin和CPZ处理对POD活性没有显著影响.这些结果暗示Ca2+/CaM信使可能主要通过调节抗氧化酶活性、脯氨酸和可溶性蛋白提高毛竹对干旱的适应性,且通过不同的传递路径调节以上生理指标.

  16. Diffusion of Ca and Mg in Calcite

    Energy Technology Data Exchange (ETDEWEB)

    Cygan, R.T.; Fisler, D.K.

    1999-02-10

    The self-diffusion of Ca and the tracer diffusion of Mg in calcite have been experimentally measured using isotopic tracers of {sup 25}Mg and {sup 44}Ca. Natural single crystals of calcite were coated with a thermally-sputtered oxide thin film and then annealed in a CO{sub 2} gas at one atmosphere total pressure and temperatures from 550 to 800 C. Diffusion coefficient values were derived from the depth profiles obtained by ion microprobe analysis. The resultant activation energies for Mg tracer diffusion and Ca self-diffusion are respectively: E{sub a}(Mg) = 284 {+-} 74 kJ/mol and E{sub a}(Ca) = 271 {+-} 80 kJ/mol. For the temperature ranges in these experiments, the diffusion of Mg is faster than Ca. The results are generally consistent in magnitude with divalent cation diffusion rates obtained in previous studies and provide a means of interpreting the thermal histories of carbonate minerals, the mechanism of dolomitization, and other diffusion-controlled processes. The results indicate that cation diffusion in calcite is relatively slow and cations are the rate-limiting diffusing species for the deformation of calcite and carbonate rocks. Application of the calcite-dolomite geothermometer to metamorphic assemblages will be constrained by cation diffusion and cooling rates. The direct measurement of Mg tracer diffusion in calcite indicates that dolomitization is unlikely to be accomplished by Mg diffusion in the solid state but by a recrystallization process.

  17. Mutations in troponin T associated with Hypertrophic Cardiomyopathy increase Ca(2+)-sensitivity and suppress the modulation of Ca(2+)-sensitivity by troponin I phosphorylation.

    Science.gov (United States)

    Messer, Andrew E; Bayliss, Christopher R; El-Mezgueldi, Mohammed; Redwood, Charles S; Ward, Douglas G; Leung, Man-Ching; Papadaki, Maria; Dos Remedios, Cristobal; Marston, Steven B

    2016-07-01

    We investigated the effect of 7 Hypertrophic Cardiomyopathy (HCM)-causing mutations in troponin T (TnT) on troponin function in thin filaments reconstituted with actin and human cardiac tropomyosin. We used the quantitative in vitro motility assay to study Ca(2+)-regulation of unloaded movement and its modulation by troponin I phosphorylation. Troponin from a patient with the K280N TnT mutation showed no difference in Ca(2+)-sensitivity when compared with donor heart troponin and the Ca(2+)-sensitivity was also independent of the troponin I phosphorylation level (uncoupled). The recombinant K280N TnT mutation increased Ca(2+)-sensitivity 1.7-fold and was also uncoupled. The R92Q TnT mutation in troponin from transgenic mouse increased Ca(2+)-sensitivity and was also completely uncoupled. Five TnT mutations (Δ14, Δ28 + 7, ΔE160, S179F and K273E) studied in recombinant troponin increased Ca(2+)-sensitivity and were all fully uncoupled. Thus, for HCM-causing mutations in TnT, Ca(2+)-sensitisation together with uncoupling in vitro is the usual response and both factors may contribute to the HCM phenotype. We also found that Epigallocatechin-3-gallate (EGCG) can restore coupling to all uncoupled HCM-causing TnT mutations. In fact the combination of Ca(2+)-desensitisation and re-coupling due to EGCG completely reverses both the abnormalities found in troponin with a TnT HCM mutation suggesting it may have therapeutic potential.

  18. Extracellular Adenosine Diphosphate Ribose Mobilizes Intracellular Ca2+ via Purinergic-Dependent Ca2+ Pathways in Rat Pulmonary Artery Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Chun Huang

    2015-11-01

    Full Text Available Background/Aims: Adenosine diphosphate ribose (ADPR, a product of β-NAD+ metabolism generated by the multifunctional enzyme CD38, is recognized as a novel signaling molecule. The catalytic site of CD38 orients extracellularly or intracellularly, capable of generating ADPR outside and inside the cells. CD38-dependent pathways have been characterized in pulmonary artery smooth muscle cells (PASMCs; however the physiological function of extracellular ADPR is unclear. Methods: Ca2+ mobilizing and proliferative effects of extracellular ADPR were characterized and compared with the ATP-induced responses in rat PASMCs; and the expression of purinergic receptor (P2X and P2Y subtypes were examined in pulmonary arteries. Results: ADPR elicited concentration-dependent increase in [Ca2+]i with a fast transient and a sustained phase in PASMCs. The sustained phase was abolished by Ca2+ removal and inhibited by the non-selective cation channel blocker SKF-96365, but was unaffected by TRPM2 antagonists or nifedipine. The purinergic receptor (P2X antagonist pyridoxal-phosphate-6-azophenyl-2', 4'-disulfonate inhibited partially the transient and the sustained Ca2+ response, while the P2(XY inhibitor suramin and the phospholipase C inhibitor U73122 abolished the sustained Ca2+ influx. The P2Y1 antagonist MRS2179 had no effect on the response. By contrast, ATP and ADP activated Ca2+ response exhibited a high and a low affinity component, and the pharmacological profile of ATP-induced Ca2+ response was distinctive from that of ADPR. BrdU incorporation assay showed that ADPR caused significant inhibition whereas ATP caused slight stimulation of PASMC proliferation. RT-PCR analysis found that almost all P2X and P2Y subtypes are expressed in PAs. Conclusion: ADPR and ATP activate Ca2+ responses through different combinations of multiple purinergic receptor subtypes; and extracellular ADPR may exert an autocrine/paracrine action via purinergic receptors on PASMCs.

  19. Clinical significance of detecting CEA, CA199, AFP, HCG, CA153, CA125 in postoperative treatment of patients with ovarian cancer

    Institute of Scientific and Technical Information of China (English)

    Xue Pan; Zhen-Hua Du

    2016-01-01

    Objective:To explore the clinical significance of carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), a tire protein (AFP), human chorionic gonadotropin (HCG), carbohydrate antigen 153 (CA153) and carbohydrate antigen 125 (CA125) in the postoperative treatment of patients with ovarian cancer.Methods:210 cases of patients with ovarian cancer after initial treatment from January 2015 to December 2015, 232 cases of patients with ovarian benign tumor and 250 cases of healthy women were selected, CEA, CA199, AFP, HCG, CA153 and CA125 levels were detected, and the levels after chemotherapy in patients with ovarian carcinoma were detected.Results:CEA, CA199, AFP, HCG, CA153 and CA125 levels in patients with ovarian cancer were (12.37±7.43) ng/mL, (84.04±26.96) U/mL, (37.46±9.47) μg/L, (110.54±35.51) IU/L, (51.23±9.20) U/mL and (64.36±42.68) U/mL, respectively, which were significantly higher than that in normal controls and patients with benign ovarian lesions, and were considered to be statistically significant. Chemotherapy after two cycles, CEA, CA199, AFP, HCG, CA153 and CA125 levels in patients with ovarian cancer were significantly lower than that before chemotherapy, and were considered to be statistically different. Chemotherapy after four cycles, CEA, CA199, AFP, HCG, CA153 and CA125 levels in patients with ovarian cancer continue to decrease, and were significantly lower than that of chemotherapy after two cycles, and had statistical differences.Conclusion:CEA, CA199, AFP, HCG, CA153 and CA125 can be used as important indicators for monitoring the chemotherapy effects, early recurrence and metastasis of ovarian cancer.

  20. Altered Ca2+ Homeostasis and Endoplasmic Reticulum Stress in Myotonic Dystrophy Type 1 Muscle Cells

    Directory of Open Access Journals (Sweden)

    Gyorgy Szabadkai

    2013-06-01

    Full Text Available The pathogenesis of Myotonic Dystrophy type 1 (DM1 is linked to unstable CTG repeats in the DMPK gene which induce the mis-splicing to fetal/neonatal isoforms of many transcripts, including those involved in cellular Ca2+ homeostasis. Here we monitored the splicing of three genes encoding for Ca2+ transporters and channels (RyR1, SERCA1 and CACN1S during maturation of primary DM1 muscle cells in parallel with the functionality of the Excitation-Contraction (EC coupling machinery. At 15 days of differentiation, fetal isoforms of SERCA1 and CACN1S mRNA were significantly higher in DM1 myotubes compared to controls. Parallel functional studies showed that the cytosolic Ca2+ response to depolarization in DM1 myotubes did not increase during the progression of differentiation, in contrast to control myotubes. While we observed no differences in the size of intracellular Ca2+ stores, DM1 myotubes showed significantly reduced RyR1 protein levels, uncoupling between the segregated ER/SR Ca2+ store and the voltage-induced Ca2+ release machinery, parallel with induction of endoplasmic reticulum (ER stress markers. In conclusion, our data suggest that perturbed Ca2+ homeostasis, via activation of ER stress, contributes to muscle degeneration in DM1 muscle cells likely representing a premature senescence phenotype.

  1. Energy deprivation transiently enhances rhythmic inhibitory events in the CA3 hippocampal network in vitro.

    Science.gov (United States)

    Gee, C E; Benquet, P; Demont-Guignard, S; Wendling, F; Gerber, U

    2010-07-14

    Oxygen glucose deprivation (OGD) leads to rapid suppression of synaptic transmission. Here we describe an emergence of rhythmic activity at 8 to 20 Hz in the CA3 subfield of hippocampal slice cultures occurring for a few minutes prior to the OGD-induced cessation of evoked responses. These oscillations, dominated by inhibitory events, represent network activity, as they were abolished by tetrodotoxin. They were also completely blocked by the GABAergic antagonist picrotoxin, and strongly reduced by the glutamatergic antagonist NBQX. Applying CPP to block NMDA receptors had no effect and neither did UBP302, an antagonist of GluK1-containing kainate receptors. The gap junction blocker mefloquine disrupted rhythmicity. Simultaneous whole-cell voltage-clamp recordings from neighboring or distant CA3 pyramidal cells revealed strong cross-correlation of the incoming rhythmic activity. Interneurons in the CA3 area received similar correlated activity. Interestingly, oscillations were much less frequently observed in the CA1 area. These data, together with the observation that the recorded activity consists primarily of inhibitory events, suggest that CA3 interneurons are important for generating these oscillations. This transient increase in inhibitory network activity during OGD may represent a mechanism contributing to the lower vulnerability to ischemic insults of the CA3 area as compared to the