Plasma Levels of Protein Z in Ischemic Stroke: A Systematic Review and Meta-Analysis

The Role of Hepcidin in Myelodysplastic Syndromes (MDS): A Systematic Review of Observational Studies

Iron overload emerges as a serious complication in myelodysplastic syndromes (MDS), particularly associated with frequent transfusions during the course of the disease. The discovery and description of hepcidin's mechanisms of action have contributed to a deeper understanding of iron metabolism. The existing literature reports a potential role of hepcidin in MDS, yet these data are fragmented and presented in an unstructured, somewhat chaotic manner. Hence, to address the existing data, we performed a systematic review of observational studies examining hepcidin levels in MDS. An extensive review of three bibliographic databases (Pubmed, Web of Science, and Scopus) enabled us to identify 12 observational studies. These studies focused primarily on adult patients with low-risk MDS who underwent transfusions and chelation therapy. An in-depth analysis of these manuscripts led to four main conclusions: (1) although high serum hepcidin levels are associated with MDS, most studies generally have not found a significant difference in these levels between patients and healthy individuals; (2) serum hepcidin levels are specific to MDS type; (3) serum hepcidin levels in MDS are strongly associated with transfusions and the genetic status of patients; and (4) high-risk MDS is associated with high serum hepcidin levels. While we have furnished a comprehensive summary of the significance of hepcidin in MDS, there are still gaps that future research should address. This pertains primarily to the capacity of hepcidin in predicting adverse outcomes for MDS patients and evaluating the efficacy of chelation therapy or the need for transfusion.

Plasma levels and urinary excretion of protein Z in patients with urolithiasis

OBJECTIVES

Protein Z (PZ) is a γ-carboxyglutamic acid protein present in plasma that is involved in blood coagulation. Detailed analysis of urinary stones from patients with urolithiasis has revealed that PZ is often found in urinary stones composed of calcium oxalate monohydrate. In this study, we compared blood and urinary PZ concentrations between healthy individuals and patients with urolithiasis.

METHODS

Plasma and urine were collected from healthy individuals and patients with urolithiasis who provided informed consent. PZ was detected as a urinary stone matrix protein in some of the patients. PZ was quantified by ELISA, creatinine was measured by the enzymatic method, and the total protein concentration was measured by the Bradford method.

RESULTS

The plasma PZ level was 2.54 ± 1.02 μg/mL in healthy individuals and that in urolithiasis patients classified by stone history were from 1.16 ± 0.77 to 3.73 ± 1.09 μg/mL, which was not significantly different. The urinary excretion of PZ (PZ/creatinine) was also not different in patients with urolithiasis and in healthy individuals (from 54.1 ± 40.9 to 95.4 ± 69.4 ng/mg vs. 73.3 ± 36.0 ng/mg). A positive correlation was found between the plasma PZ level and creatinine-corrected urinary PZ concentration (r = 0.46).

CONCLUSIONS

Both the plasma level and urinary excretion of PZ in urolithiasis patients were not significantly different with normal individuals. PZ detected in urinary stones as a matrix protein is thought to be incorporated into urinary stones regardless of blood and urine levels of PZ.

Protein Z and Protein Z-dependent protease inhibitor in patients with acute ischemic stroke: A prospective mechanistic study

OBJECTIVES

Protein Z (PZ) /Protein Z-dependent protease inhibitor (ZPI) (PZ/ZPI) system is a new anticoagulant system discovered in recent years, which plays an important role in many diseases. We aimed to compare the plasma PZ/ZPI levels of acute ischemic stroke (AIS) patients and non-stroke control participants and the role of PZ/ZPI in the development of stroke was preliminarily analyzed.

MATERIALS AND METHODS

Enzyme linked immunosorbent assay (ELISA) was used to detect and compare plasma PZ levels of 86 patients with acute AIS and 85 non-stroke control patients. Multivariable Logistic regression was used to analyze whether PZ was an independent risk factor for AIS.

RESULTS

In the present study, plasma PZ is closely related to inflammatory response, coagulation process and platelet activation, and may participate in the development of AIS by inducing inflammatory responses and interfering with the coagulation process.

CONCLUSIONS

Our results suggested that plasma PZ level is one of the independent risk factors of AIS, and plasma ZPI was closely related to coagulation and platelet parameter and may play a role in the coagulation process during AIS.

Hepcidin in Children and Adults with Acute Leukemia or Undergoing Hematopoietic Cell Transplantation: A Systematic Review

Objectives: The association between hepcidin and acute leukemia (AL) or hematopoietic cell transplantation (HCT) in children and adults remains obscure. We aimed to assess this potential relationship through a systematic review of observational studies. Methods: An electronic search of three databases, including PubMed, Scopus, and Web of Science Core Collection, was performed up to 31 March 2022. Two independent reviewers assessed the search results according to predetermined inclusion and exclusion criteria, following PRISMA guidelines. Results: Of the 3607 titles identified, 13 studies published between 2008 and 2021 met the inclusion criteria. Most studies included a moderate number of participants and controls and used enzyme-linked immunosorbent assay (ELISA) to determine serum hepcidin levels. The principal findings: (1) serum hepcidin levels in patients with AL or undergoing HCT are increased compared to controls, regardless of the patient’s age and the phase of disease treatment; (2) AL therapy and HCT significantly influence serum hepcidin levels; (3) serum hepcidin may predict a worse outcome in patients with AL and post-HCT. Conclusions: This systematic review provides an overview of observational studies that deal with the association of hepcidin with AL and HCT. Although disturbances in iron metabolism are common in AL and HCT, and hepcidin seems to play a cardinal role in their modulation, more extensive research is needed.

Hemostasis in Coronavirus Disease 2019-Lesson from Viscoelastic Methods: A Systematic Review

Hemostatic unbalance is often observed in patients with coronavirus disease 2019 (COVID-19), and patients with severe disease are at high risk of developing thromboembolic complications. Viscoelastic methods (VEMs), including thrombelastography (TEG) and thromboelastometry (TEM), provide data on the nature of hemostatic disturbance. In this systematic review, we assessed the performance of TEG and TEM in the assessment of blood coagulation and fibrinolysis in patients with COVID-19. PubMed, Scopus, Web of Science Core Collection, medRxiv, and bioRxiv were systematically searched for clinical studies evaluating TEG and/or TEM variables in COVID-19 individuals. Ten studies, with a total of 389 COVID-19 patients, were included, and VEMs were performed in 292 of these patients. Most patients (90%) presented severe COVID-19 and required mechanical ventilation. TEG and TEM variables showed that these patients displayed hypercoagulability and fibrinolysis shutdown, despite the use of appropriate thromboprophylaxis. However, the mechanism underlying these phenomena and their clinical significance in COVID-19 patients who developed thrombosis are still not clear. Further studies are warranted if VEMs might help to identify those at highest risk of thrombotic events and who therefore may derive the greatest benefit from antithrombotic therapy.