Plasma Concentrations of Protein Z and Protein Z-Dependent Protease Inhibitor in Thalassemia Major Patients

Background: Better survival of thalassemia patients allowed previously unrecognized renal complications to emerge. Objectives: Assess prevalence and early predictors of renal dysfunction in young β-thalassemia major (β-TM) and intermedia (β-TI) patients. Subjects: 66 β-TM (group I), 26 β-TI (group II) Egyptian patients and 40 healthy controls. Methods: History, examination and investigations that included kidney function tests, serum ferritin, serum bicarbonate, plasma osmolality and urinary total proteins, microalbuminuria (MAU), N-acetyl-β-D-glucosaminidase (NAG), retinol binding protein (RBP), α-1 microglobulin, bicarbonate, osmolality, Creatinine clearance (CrCl), % fractional excretion of bicarbonate (% FE-HCO3). Results: The most common renal abnormality was proteinuria (71%), followed by increased urinary level of RBP (69.4%), NAG (58.1%), α-1 microglobulin (54.8%) and microalbumin (29%) and also decreased urinary osmolality (58.1%). Although serum creatinine and BUN were not statistically different between thalassemia patients and control, CrCl were significantly lowered in thalassemia patients. Total serum protein and albumin was significant lower in splenectomized β-TM, whereas urinary total protein and MAU were significantly increased in all thalassemia patients. NAG, RBP and α-1 microglobulin were negatively correlated with CrCl and positively correlated with serum ferritin and urinary total protein. Z-score analysis for discrimination of patients with renal dysfunction proved superiority of urine total protein and RBP. Comparative statistics of different frequencies revealed significant difference between the urinary total protein and both MAU and % FE-HCO3. Conclusion: Asymptomatic renal dysfunctions are prevalent in young β-TM and β-TI patients that necessitate regular screening and urinary total protein and RBP may be cost-effective for early detection.

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Tin Selenide Quantum Dots Electrochemical Biotransducer for the Determination of Indinavir - A Protease Inhibitor Anti-Retroviral Drug

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.45.12 ◽

2017 ◽

Vol 45 ◽

pp. 12-24

Author(s):

Usisipho Feleni ◽

Rachel Fanelwa Ajayi ◽

Abongile Jijana ◽

Unathi Sidwaba ◽

Samantha Douman ◽

...

Keyword(s):

Quantum Dots ◽

Protease Inhibitor ◽

Limit Of Detection ◽

Plasma Concentrations ◽

Calibration Plot ◽

Maximum Plasma ◽

Reduction Peak ◽

Broad Absorption Band ◽

Mercaptopropionic Acid ◽

Tin Selenide

Biocompatibility of tin selenide quantum dots was achieved by the incorporation of 3-mercaptopropionic acid (3-MPA) as a capping agent, which also improved the stability and the solubility of the material. The UV-Vis spectrophotometric analysis of the quantum dots revealed a broad absorption band at ~ 330 nm (with a corresponding band gap, Eg, value of 3.75 eV), which is within the range of values expected for quantum dots materials. The 3-mercaptopropionic acid-capped tin selenide (3-MPA-SnSe) quantum dots were used to develop an electrochemical biosensor for indinavir, which is a protease inhibitor antiretroviral (ARV) drug. The biosensor was prepared by the self-assembly of L-cysteine on a gold electrode that was functionalised with 3-MPA-SnSe quantum dots, followed by cross-linking with cytochrome P450-3A4 (CYP3A4) using 1-ethyl-3(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The electrocatalytic properties of the biosensor included a characteristic cyclic voltammetric reduction peak at-380 mV, which was used to detect the response of the biosensor to indinavir. The sensor performance parameters included response time and limit of detection (LOD) values of 11 s and 3.22 pg/mL, respectively. The test concentration range studied (0.014 – 0.066 ng/mL) gave a linear calibration plot for indinavir, and it was lower than the physiological plasma concentration index (i.e. maximum plasma concentrations, Cmax,) of indinavir (5 - 15 ng/mL) normally observed 8 h after intake. This indicates that the biosensor can be very useful in the case of ultra-rapid metabolisers where very low Cmax values are expected

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Unique secretion mode of human protein Z: its Gla domain is responsible for inefficient, vitamin K–dependent and warfarin-sensitive secretion

Blood ◽

10.1182/blood-2008-07-171884 ◽

2009 ◽

Vol 113 (16) ◽

pp. 3857-3864 ◽

Cited By ~ 7

Author(s):

Masayoshi Souri ◽

Hiroki Iwata ◽

Wei Guang Zhang ◽

Akitada Ichinose

Keyword(s):

Vitamin K ◽

Plasma Concentrations ◽

Factor X ◽

Protein Z ◽

Highly Sensitive ◽

Carboxyglutamic Acid ◽

Secretion Mode ◽

Gla Domain ◽

The Difference ◽

Acid Domain

Abstract Protein Z is a vitamin K–dependent plasma glycoprotein that is involved in the regulation of blood coagulation. Plasma concentrations of protein Z vary widely between subjects and are greatly reduced during warfarin therapy. We developed a sensitive and quantitative assay for protein secretion using a secretory luciferase to explore the mode of secretion of protein Z compared with that of factor X. Protein Z secretion was much less efficient than factor X and was totally dependent upon added vitamin K, while factor X secretion was not. Protein Z secretion was highly sensitive to warfarin treatment of the synthesizing cells. In contrast, although factor X secretion was not precluded by warfarin, its γ-carboxylation was completely blocked. An exchange of the propeptide and/or γ-carboxyglutamic acid domain between protein Z and factor X reproduced the inefficient and warfarin-sensitive secretion pattern of protein Z, and vice versa. Joining of the propeptide and γ-carboxyglutamic acid domain to luciferase also demonstrated that the γ-carboxyglutamic acid domain of protein Z was responsible for its warfarin-sensitive secretion. Thus, it was concluded that the difference observed in secretion patterns of protein Z and factor X was mainly based on the structure of their γ-carboxyglutamic acid domains.

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Autoimmune antiphospholipid antibodies impair the inhibition of activated factor X by protein Z/protein Z-dependent protease inhibitor

Journal of Thrombosis and Haemostasis ◽

10.1046/j.1538-7836.2003.00303.x ◽

2003 ◽

Vol 1 (8) ◽

pp. 1764-1770 ◽

Cited By ~ 37

Author(s):

R. R. Forastiero ◽

M. E. Martinuzzo ◽

L. Lu ◽

G. J. Broze

Keyword(s):

Protease Inhibitor ◽

Antiphospholipid Antibodies ◽

Factor X ◽

Protein Z ◽

Z Protein

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Thrombin-Releasable Protein Z-Dependent Protease Inhibitor Identified in Platelets and Is Likely Due to Uptake from Plasma.

Blood ◽

10.1182/blood.v110.11.1751.1751 ◽

2007 ◽

Vol 110 (11) ◽

pp. 1751-1751

Author(s):

Xin Han ◽

Martin H. Nguyen ◽

Michael Fernandez ◽

George J. Broze ◽

Carlos E. Bueso-Ramos

Keyword(s):

Bone Marrow ◽

Western Blot ◽

Protease Inhibitor ◽

Blot Analysis ◽

Western Blot Analysis ◽

Factor Xa ◽

Human Populations ◽

Rt Pcr ◽

Protein Z ◽

Platelet Factor

Abstract Protein Z (PZ) is a vitamin K-dependent protein, whereas PZ-dependent protease inhibitor (ZPI) is a member of the serine protease inhibitor superfamily. ZPI rapidly inhibits factor Xa in the presence of PZ, calcium, and phospholipids and inhibits factor XIa in a PZ-independent fashion (Blood2000; 96:3049–3055). PZ circulates as a complex with ZPI in plasma and deletion of either the PZ or the ZPI gene is associated with the prothrombotic phenotype in mice. In addition, W303X or R67X nonsense mutations in the ZPI gene are reportedly associated with deep venous thrombosis in certain human populations. Western blot analysis of platelets stimulated with thrombin (0–200 mU/mL) showed they contained and released ZPI (approximately 200 ng/109 platelets) with the same molecular weight as plasma ZPI (72 kDa). The majority of the ZPI was released within 1 min. by 25 mU/mL thrombin. PZ was not detected in platelets by western blot analysis. Immunohistochemical staining using a monoclonal anti-ZPI antibody demonstrated a cytoplasmic fine granular staining pattern in maturing megakaryocytes in bone marrow aspirates and in circulating platelets, suggesting that ZPI may be stored in alpha granules. ZPI mRNA, however, was not detected by reverse transcriptase polymerase chain reaction (RT-PCR) in platelets or bone marrow aspirates, but was detected in human liver cDNA. RT-PCR for platelet factor 4 and glyceraldehyde 3-phosphate dehydrogenase mRNA showed amplified products with expected sizes. In conclusion, thrombin-releasable ZPI, but not PZ, is present in platelets and is most likely derived from the uptake of ZPI from plasma. ZPI released from activated platelets may play a role in the regulation of local coagulation at a site of injury.

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