Transthyretin (TTR) is a protein containing 20-40mg/dl in plasma with a half life of 1.9 days. TTR is detected in cerebrospinal fluid with high concentration, and plays important roles in the pathogenesis of brain disorders, such as Alzheimer disease, schizophrenia, and lead intoxication. TTR functions as a tetramerer binding with retinol binding protein (RBP) and T4. Because TTR is a Trp rich protein, it becomes a good maker for evaluating nutritional state in the acute phase of diseases. However, the protein is an antiacute phase protein and plasma concentration is decreased by infection and inflammation. Since TTR is β-sheet rich protein, it is prone to form amyloid fibrils both in vitro and in vivo. It can become the precursor protein of familial amyloidotic polyneuropathy (FAP) and senile systemic amyloidosis (SSA). Because TTR is predominantly synthesized by the liver, liver transplantation is a common therapy for FAP. Recently, it has been well documented that TTR plays important roles in diabetes merits, lipid metabolism disorders as well as cerebral disorders.

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Establishment of working standard for the measurements of total calcium and total magnesium in serum has been studied. This working standard of prototype was prepared by using normal human serum, and adjusting concentration of calcium, magnesium, sodium, potassium and chloride, and pH to those of human serum by the guideline of Committee on Quality Management of JSCC. The working standard of prototype is sealed in vials and frozen to be stored. The values assigned to this working standard of prototype were determined for total calcium and total magnesium by the NIST reference method using an atomic absorption spectrophotometry.
The conformity of this reference material of prototype to patient serum make it possible for clinical laboratories to evaluate the trueness of their automated clinical analyzers for total calcium and total magnesium measurement. In addition, the evaluation of inaccuracy in clinical laboratories can be carried out with ease. Thus the traceability for total calcium and total magnesium measurement will be established with this working standard of prototype.

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Four International Societies published the statement that, for the standardization of hemoglobin Alc(HbAlc), analytical results should be presented in the both units of IFCC and NGSP. The Committee of Diabetes Mellitus Indices of JSCC was commented acceptance of this statement. The Committee on Standardization of Laboratory Testing for Diabetes Mellitus of JDS is now under working with a standpoint of acceptance of the two units.
The both committees started arrangement of circumstances for the standardization of HbAlc measurement in Japan. Thus, a guideline for reporting IFCC units and JDS units on measurement of HbAlc is needed for a practical purpose of manufacturers and end-users in Japan.
In the present guideline, the traceability chain being built up on the IFCC peptide mapping procedure as an anchor method, constitution of matrix reference materials for reference and working standards, master equations for the reporting the IFCC and JDS units and/or the IFCC and NGSP units, the criteria of specification of the master equations, and the control system of the HbAlc measurement in routine measurement procedures will be served.
The following studies are still remaining: to assign total Hb and HbAlc concentrations as the certified values, to determine the allowance and control limits of the IFCC units in a routine laboratory, to examine the reference intervals and clinical target values using the IFCC unit, to assess the reference system of HbAlc measurement the IFCC unit, and to educate the laboratory staffs, clinicians, and patients on the IFCC unit in the routine medical care.

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Neuroblastoma is a tumor of nerve tissue in childhood. Mass-screening program for early detection of neuroblastoma was stopped in Japan because of its inability of precise clarification of malignant tumor. We aimed to find out new tumor markers which could be used in future mass-screening, and have succeeded to establish LC-MS/MS-based quantification of nine urinary catecholamine metabolites. The standard curves of these nine metabolites showed high linearity and reproducibility, thus we applied them to measure the content of the metabolites in patient samples. The results showed a possibility that the ratio of DOPAC and normetanephrine could be a marker of tumors whereas each metabolite alone could not. In addition, we made a survey of candidate neuroblastoma markers in urine using a Q-q-TOF/MS. We found fifteen increased and eight decreased ion peaks in seven tumor samples. We will confirm their ability as diagnostic markers of neuroblastoma by increasing case numbers.

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