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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Alkaline phosphatase and the cell envelope of Pseudomonas aeruginosa.

Day, Donal F. January 1973 (has links)
No description available.
22

The significance of placental and placental-like alkaline phosphatases in tumor biology and their potential use in clinical practice

Jeppsson, Annika January 1984 (has links)
Placental alkaline phosphatase (PLAP) is a membrane bound enzyme normally synthesized by the syncytiotrophoblasts in the human placenta. Recent studies have indicated that trace amounts of placental-like alkaline phosphatases also are present in several normal organs like testes and endocervix. PLAP and PLAP-1ike enzymes are furthermore synthesized by some tumors and can be detected in sera of approximately 12 % of patients with any type of cancer, more often in patients with genital tumors. This synthesis has been considered to be ectopic.PLAP is known to be electrophoretically highly polymorphic. Both poly- and monoclonal antibodies were used to study this enzyme. One of the monoclonal antibodies was able to discriminate between different phenotypes of PLAP and thus immunochemical approaches to elucidate enzyme polymorphism were established.To evaluate the potential clinical use of PLAP as a tumor marker serum levels of the enzyme were measured by a radioimmunoassay in 100 patients with the testicular tumor seminoma. Elevated levels of PLAP were found in 43 % of the patients with primary tumors and in 75 % of the patients with recurrent or metastatic disease. After successful treatment of seminoma the PLAP levels decreased. This indicates that measuring PLAP give useful information during follow up of treatment of seminomas.The content of PLAP-like enzymes in seminoma tumors was determined in 13 typical seminomas. The levels, of enzyme found in the tumor tissue ranged from 870-13 404 ng/g wet weight, which should be compared to around 100 ng/g in normal testes. Analysis using monoclonal antibodies and enzyme inhibitors showed the PLAP-like enzymes present in seminomas to be similar to the enzymes in normal testes. This suggests that the increased expression of PLAP-like enzymes in seminomas results from an enhanced eutopic expression of enzymes found in normal testis.A sensitive catalytic assay was used to quantify enzyme levels in sera from women with malignant gynaecological tumors. In the group of patients with cervical carcinoma 68 % had values exceeding the normal limit. For patients with ovarian cancer and carcinoma of the breast the percentages were 35 and 23 respectively.Monoclonal and polyclonal antibodies against PLAP were evaluated for tumor immunolocalization of human PLAP-producing tumors in nude mice.The antibodies were labeled with "125j and injected into mice with tumors. The distribution of 25j_an-ti-PLAP in various tissues showed that the labeled antibodies were enriched in the tumors, with a mean concentration ratio of 7. This indicates that there is a potential use of PLAP in localizing tumors in humans. / <p>S. 1-37: sammanfattning, s. 39-88: 5 uppsatser</p> / digitalisering@umu
23

Association of vitamin D (1,25OHD, 25OHD and vitamin D binding protein) and alkaline phosphatase with orthodontic tooth movement and osteoblast function

Tashkandi, Nada 24 June 2019 (has links)
INTRODUCTION: In this study, we identified the association of Vitamin D with orthodontic tooth movement and the impact of Vitamin D 1,25OHD and 25OHD forms on osteoblast function. MATERIALS AND METHODS: This study is comprised of two parts; a clinical and a laboratory part. In part I, saliva samples were collected from orthodontic patients each month for the first six months of orthodontic treatment along with casts at the beginning and the end of the study period. The samples were measured for Vitamin D binding protein (VitDBP) and alkaline phosphatase (ALP) and correlated with clinical tooth movement using absolute change in irregularity index (II). In part II, osteoblasts were collected from the calvaria of 3-5 day old healthy wild-type mice and cultured with differing concentrations of 1,25OHD (1, 10 and 100nmol) and 25OHD (100, 200, 400 nmol). ALP, OPG, and RANKL were measured as outcomes of Vitamin D treatment of osteoblasts. Intracellular signaling in response to Vitamin D was assessed by identifying the phosphorylation of ERK 1/2, p38 and NLK in primary osteoblasts. RESULTS: Measurement of salivary Vitamin D binding protein (VitDBP) showed that both low (<2.75 ng/ml) and high (>6.48 ng/ml) logVitDBP were associated with reduced tooth movement. There was no significant correlation between ALP levels and orthodontic treatment. Significant seasonal changes in VitDBP using a two-season year model were found with lower levels noticed in the summer (Mar-Sept) than in the winter (Oct-Feb) at p<0.05. A decrease in OPG production with higher concentrations of 1,25OHD and 25OHD with a corresponding increase in RANKL levels in primary osteoblast cultures was found. Similar to the clinical findings, ALP levels were not significantly affected by increasing concentrations of both 1,25OHD and 25OHD. The ERK 1/2 showed upregulation in response to treatment with 1,25OHD and downregulation in response to treatment with 25OHD concentrations. Meanwhile, p38 and NLK were affected by 1,25OHD and not by 25OHD. CONCLUSIONS: Clinical outcomes of orthodontic treatment are associated with a range of optimal Vitamin D binding protein (VitDBP) as detected in saliva. Different forms of Vitamin D affect osteoblast response and signaling differently.
24

Ethnic differences in adipogenesis and the role of alkaline phosphatase in the control of adipogenesis in human preadipocytes and 3T3-L1 cells

Ali, Aus Tarig 07 1900 (has links)
A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirement for the degree of Doctor of Philosophy. Johannesburg, 2004 / Alkaline phosphatase (ALP) is a ubiquitously expressed enzyme, that has been shown to play a role in cell differentiation and organogenesis. One study has also demonstrated ALP activity in rat adipocytes. The purpose of the present study was therefore to determine whether ALP is expressed in preadipocytes and what role it may have in adipogenesis. ALP activity was detected in the murine preadipocyte cell line, 3T3-L1, and in human preadipocytes isolated from mammary tissue, and from subcutaneous abdominal fat depots. In all the cell types studied ALP activity increased in parallel with adipogenesis. In the 3T3 -L1 cell line the tissue- non -specific ALP inhibitors, levamisole and histidine inhibited ALP activity, and adipogenesis, whereas the tissue specific ALP inhibitor Phe- Gly-Gly did not inhibit ALP or adipogenesis. In human preadipocytes, histidine inhibited adipogenesis and ALP activity, whereas levamisole inhibited adipogenesis, but did not block ALP activity in intact cells. However, levamisole did inhibit ALP activity by 50% in cell extracts. Levamisole was able to inhibit adipogenesis in human preadipocytes. The tissue specific ALP inhibitor, Phe Gly Gly, did not inhibit ALP activity or adipogenesis in human preadipocytes. ALP activity and adipogenesis, were compared in preadipocytes isolated from mammary tissue taken from black (13) and white (15) female subjects. Both ALP activity and adipogenesis, were lower in white compared to black female subjects. iii Immunocytochemical, analysis of the 3T3-L1 cell line and human preadipocytes demonstrated that ALP activity was restricted to the lipid droplets of these cells. ALP activity was also measured in serum samples obtained from 100 African subjects (74 females and 26 males) of varying BMI. ALP activity was found to be higher in obese than lean subjects, whereas, the other liver enzymes or products measured in serum were not. In fact these variables correlated to varying degrees with waist-hip ratio, whereas ALP levels did not. This suggest that liver function is predominantly influenced by abdominal obesity whereas serum ALP levels are more influenced by overall body adiposity. In conclusion, ALP, may be involved in the control of adipogenesis, in the 3T3- L1 preadipocyte cell line and in human preadipocytes isolated from mammary adipose tissue and subcutaneous abdominal adipose tisssue. The presence of ALP activity in lipid droplets in 3T3-L1 cells and human preadipocytes, and the ability of ALP inhibitors to block adipogenesis strongly suggest that ALP plays a role in the control of adipogenesis. / IT2017
25

Application of porous gold enzyme electrode in electrochemical Flow injection analysis.

Chang, Jing-shun 13 July 2004 (has links)
None
26

Continuous flow microwave heating : evaluation of system efficiency and enzyme inactivation kinetics

Lin, Man Guang, 1966- January 2004 (has links)
A continuous flow microwave heating system was set up by using one domestic microwave oven (1000W nominal output at 2450MHz). Water was run through the coil centrally located inside the oven cavity for microwave heating. Microwave absorption efficiency was evaluated by measuring inlet and outlet temperatures of coil as a function of system variables. In order to optimize the coil configuration, the influence of tube diameter (6.4, 7.9 and 9.7mm); initial temperature (10, 20 and 30 ºC); number of turns (3.5, 4.5 and 5.5); coil diameter (61.5, 88, 102, 121 and 153 mm) and pitch (16, 18, 20, 22 and 24mm) were evaluated, respectively at different flow rates (240, 270, 300, 330 and 360ml/min). In helical systems, Dean number is used as a measure of secondary flow which enhances mixing of the fluid providing uniform heating even under laminar flow conditions. Results showed that microwave absorption efficiency was a compromise between coil volume and Dean number. Therefore, a helical coil (110 mm high) with a coil diameter of 108 mm, tube diameter of 8.2 mm, 5.5 turns demonstrated the highest efficiency, fast heating rate, more uniform heating and less temperature fluctuations. The optimized coil configuration parameters were used subsequently to set up continuous-flow microwave heating system.
27

Amniotic fluid alkaline phosphatase as a biomarker of fetal growth and development Joanna Cheung.

Cheung, Joanna. January 1900 (has links)
Thesis (M.Sc.). / Written for the School of Dietetics and Human Nutrition. Title from title page of PDF (viewed 2007/08/30). Includes bibliographical references.
28

The effect of training status and an acute bout of endurance exercise on osteoblast proliferation and alkaline phosphatase activity

Timmerman, Kyle L. January 2003 (has links)
Thesis (M.S.)--Purdue University, 2003. / Includes bibliographical references (leaves 41-49).
29

Developmental regulation of alkaline phosphatase in Dictyostelium discoideum

Mohandas, Devaki Velayudhan January 1983 (has links)
The membrane bound alkaline phosphatase activity' in vegetative cells of Dictydstelium discdideum was found to exhibit a 8 to 10 fold increase in specific activity when incubated at 50°C. This activation was reversed on transfer of the preparation to 0°C. Similar activation of the vegetative enzyme was achieved by dialysing the crude membrane preparation, suggesting the removal of a low molecular weight inhibitor. Alkaline phosphatase solubilized from the membranes using Triton X-100 was similarly activated by 50°C treatment or dialysis and the 50°C activation was reversed by incubation at 0°C. Both the dialysed vegetative membrane and the dialysed Triton X-100 extract were inhibited by the addition of concentrated dialysate. This inhibition could be relieved by subsequent dialysis. A 620 fold purified alkaline phosphatase preparation was obtained from crude vegetative membranes by affinity and ion exchange chromatography after solubilization of the enzyme using Triton X-100-5'-nucleotidase activity copurified along with the alkaline phosphatase activity in all the fractionation steps employed. The membrane bound 5'-nucleotidase activity was not activated either by incubation at 50°C or by dialysis and the activity was far less stable than the alkaline phosphatase. However, the Triton X-100 extracted 5'-nucleotidase was activated by dialysis to the same extent as the alkaline phosphatase and both activities in the partially purified preparation were equally inhibited by the dialysates from vegetative membranes. These results suggest that both alkaline phosphatase and 5'-nucleotidase are due to a single protein but the interaction of the two substrates, AMP and pNPP, with the enzyme are different and are markedly influenced by conformational changes induced by the inhibitor. Unlike the vegetative enzyme, the alkaline phosphatase activity in the culminating membrane was not markedly activated by incubation at 50°C or by dialysis. Since the vegetative enzyme was activated by both treatments to levels similar to those found in culminating cells, it was proposed that the developmental increase in alkaline phosphatase in D.discoideum was due to the unmasking of already existing enzyme by the removal of inhibitor. However, the alkaline phosphatase activity of culminating cells differed from that of vegetative cells in chromatography on DEAE-Sephacel and conA-Sepharose and it was less stable in low concentrations of Tris-Cl and in SDS. In contrast, the culminating enzyme was more stable in high concentrations of Tris-Cl. These results suggest that the vegetative enzyme is modified during development. This modification appears to be slight, since the vegetative and culminating enzymes migrate identically in SDS polyacrylamide electrophoretic gels and the enzymes from the two developmental stages were similar in pH optima, in inhibition by phosphate and in inhibition by concentrated dialysate. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate
30

Morbidity and Mortality Associated With Paget's Disease of Bone: A Population-Based Study

Wermers, Robert, Tiegs, Robert D., Atkinson, Elizabeth J., Achenbach, Sara J., Melton, L. Joseph 01 June 2008 (has links)
Introduction: Limited information is available about the clinical features of Paget's disease of bone among unselected patients in the community. We examined morbidity and mortality associated with this condition in a large inception cohort of Olmsted County, MN, residents with a new diagnosis of Paget's disease from 1950 through 1994. Materials and Methods: Survival was estimated using the Kaplan-Meier method. Cox proportional hazards models were used to assess the impact of various covariates on death. Results: Paget's disease of bone was diagnosed in 236 Olmsted County residents (mean age at diagnosis, 69.6 yr; 55% men). The majority were symptomatic at diagnosis (58%), and the proportion with symptoms did not change from the prescreening era (1950 to June 1974) to the postscreening era (July 1974-1994). Most patients had polyostotic disease (72%), and the pelvis (67%), vertebra (41%), and femur (31%) were the most common sites of involvement. Skeletal complications attributable to Paget's disease included bowing deformities (7.6%), fracture of pagetic bone (9.7%), and osteosarcoma (0.4%). Osteoarthritis was observed in 73% of patients, and 11% had a hip or knee replacement. Nonskeletal complications related to Paget's disease included cranial nerve (0.4%), peripheral nerve (1.7%), and nerve root (3.8%) compression, basilar invagination (2.1%), hypercalcemia (5.2%), and congestive heart failure (3.0%). Hearing loss, noted in 61%, was significantly higher than previously reported. Conclusions: Compared with white Minnesota residents, overall survival was slightly better than expected (p = 0.010). No clinical risk factors were identified that were associated with an increased risk of death.

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