Determination of a Serum 25-Hydroxyvitamin D Reference Ranges in Japanese Adults Using Fully Automated Liquid Chromatography-Tandem Mass Spectrometry

BACKGROUND

Despite an increasing interest in vitamin D status, a reference range of the nutrient has not been fully established. This is partly due to a paucity of standardized measuring systems with high throughput. In addition, the range may vary by populations and may change with modernization of lifestyles.

OBJECTIVES

This study aims to calculate the current reference concentration of 25-hydroxyvitamin D (25(OH)D) among healthy people living in an urban area in Japan.

METHODS

A newly developed fully automated liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) system was used to measure serum 25(OH)D concentrations. Reproducibility was assessed by measuring standardized samples. Accuracy was validated by comparing with commercially available immunoassays. Then, mass screening was conducted targeting participants who received medical checkups in Tokyo from April 2019 to March 2020, and the reference ranges were calculated.

RESULTS

The coefficients of variations of interoperator and interday reproducibility were 4.1%-8.5% and 3.7%-8.0% for 25-hydroxyvitamin D₂ (25(OH)D2) and 4.7%-7.0% and 4.0%-6.9% for 25-hydroxyvitamine D3, respectively. The measured total 25(OH)D concentrations correlated well with those measured by immunoassays. In total, 5518 participants were measured for 25(OH)D concentrations, among whom 98% showed inadequate concentrations (<30 ng/mL). The reference ranges of total 25(OH)D for female, male, and total participants were 7-30 ng/mL, 5-27 ng/mL, and 6-29 ng/mL, respectively. After excluding those with abnormal renal and liver function, the range was 6-30 ng/mL.

CONCLUSIONS

The high prevalence of vitamin D insufficiency among seemingly healthy population may be attributed to lifestyle characteristics of people living in urban areas of Japan, including spending less time outdoors and lower intake of traditional foods. Longitudinal follow-up and mass screenings targeting different population will help elucidate reasons for discrepancies between official guidelines and the observed concentrations, to which the well-validated measurement system is essential.

Cell-free and concentrated ascites reinfusion therapy (CART) for management of massive malignant ascites in gastric cancer patients with peritoneal metastasis treated with intravenous and intraperitoneal paclitaxel with oral S-1

BACKGROUND

Massive malignant ascites originating from peritoneal metastasis of gastric cancer is difficult to control and resistant to chemotherapy. Cell-free and Concentrated Ascites Reinfusion Therapy (CART) is one of the types of apheresis therapy, by which filtered and concentrated ascites containing albumin and globulin is reinfused intravenously to patients. We retrospectively studied the feasibility of intraperitoneal (IP) chemotherapy combined with CART in gastric cancer patients with massive malignant ascites.

METHODS

Paclitaxel (PTX) was administered via an IP access port implanted in the subcutaneous space. If patient had massive ascites at the start of treatment, paracentesis was performed through a percutaneous IP catheter and then CART was performed. PTX was administered through the catheter until the ascites diminished.

RESULTS

A total of 127 CART procedures in 30 patients were analyzed. The average volume of processed ascites was 3.1 L, which was concentrated to 0.33 L containing 85.5 g protein on average. Significant increases in urine volume, serum total protein and albumin level were found after the CART. Increase in body temperature (0.3°C), decrease in platelet count (3.8 × 10(4)/μl), and changes in blood pressure (2 mm Hg) were found after the CART procedure, but no clinically significant adverse event was experienced. The median survival time and 1-year survival of 30 patients who received IP chemotherapy combined with the CART procedure was 10.2 months and 43.3% respectively.

CONCLUSIONS

IP chemotherapy combined with CART might be a promising strategy for patients with massive malignant ascites originating from peritoneal metastasis of gastric cancer.

A simple device using magnetic transportation for droplet-based PCR

The Polymerase chain reaction (PCR) was successfully and rapidly performed in a simple reaction device devoid of channels, pumps, valves, or other control elements used in conventional lab-on-a-chip technology. The basic concept of this device is the transportation of aqueous droplets containing hydrophilic magnetic beads in a flat-bottomed, tray-type reactor filled with silicone oil. The whole droplets sink to the bottom of the reactor because their specific gravity is greater than that of the silicone oil used here. The droplets follow the movement of a magnet located underneath the reactor. The notable advantage of the droplet-based PCR is the ability to switch rapidly the proposed reaction temperature by moving the droplets to the required temperature zones in the temperature gradient. The droplet-based reciprocative thermal cycling was performed by moving the droplets composed of PCR reaction mixture to the designated temperature zones on a linear temperature gradient from 50 degrees C to 94 degrees C generated on the flat bottom plate of the tray reactor. Using human-derived DNA containing the mitochondria genes as the amplification targets, the droplet-based PCR with magnetic reciprocative thermal cycling successfully provided the five PCR products ranging from 126 to 1,219 bp in 11 min with 30 cycles. More remarkably, the human genomic gene amplification targeting glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was accomplished rapidly in 3.6 min with 40 cycles.

Clusterin is up-regulated in glomerular mesangial cells in complement-mediated injury

BACKGROUND

Clusterin is a soluble complement regulatory protein that binds to C5b-7 and inhibits generation of membrane attack complex, C5b-9. Glomerular deposition of clusterin has been observed in human and experimental membranous nephropathy in association with C5b-9 and immune deposits. However, it is controversial as to whether clusterin observed in glomeruli is synthesized by the resident glomerular cells or is derived from the circulation. We examined whether clusterin is expressed by resident glomerular cells exposed to complement-mediated injury.

METHODS

In vitro, cultured mesangial cells were exposed to antithymocyte serum immunoglobulin G and 5% normal rat serum as a complement source. In vivo, we induced anti-Thy1 nephritis in rats and examined the kidneys on days 8 and 29.

RESULTS

We observed increased expression of clusterin in cultured rat glomerular mesangial cells stimulated by sublytic complement attack. We also demonstrated that in comparison with control rats, both a marked increase in clusterin mRNA in the glomeruli and marked deposition of clusterin protein in the mesangial area occurred in the OX-7-treated rats on day 8 in association with C5b-9 deposition and on day 29.

CONCLUSION

Clusterin was induced in glomerular mesangial cells during the course of immune-mediated injuries. This up-regulation of clusterin may play a critical role in protecting mesangial cells from complement attack.

Crry, a complement regulatory protein, modulates renal interstitial disease induced by proteinuria

Crry, a complement regulatory protein, modulates renal interstitial disease induced by proteinuria.

BACKGROUND

Recent studies have suggested a role for urinary complement components in mediating tubulointerstitial damage, which is known to have a good correlation with progression of chronic renal diseases. Although accumulating evidence suggests that complement regulatory proteins play an important protective role in glomeruli, their role in renal tubules remains unclear. In order to establish the role of a complement regulatory protein, Crry, in renal tubular injury, we employed a molecular biological approach to block the expression of Crry in tubules of animals with proteinuria induced with puromycin aminonucleoside nephritis (PAN). Methods and Results. Two different antisense oligodeoxynucleotides (ODNs) against Crry were designed and applied to cultured rat mesangial cells in vitro in order to establish their efficacy. Antisense ODN treatment resulted in decreased expression of Crry protein associated with increased sensitivity to complement attack in cell lysis assays compared with control ODN treatment or no treatment (44.7, 1.50, and 1.34%, respectively). Antisense ODNs did not affect the expression of Thy1 as a control, confirming the specificity of our ODNs. In vivo, we performed selective right renal artery perfusion to administer antisense ODNs to the kidney and showed prominent uptake of ODNs by proximal tubular cells. Reduced expression of Crry protein was demonstrated in proximal tubular cells in antisense ODNs-treated kidneys. Normal rats treated with the antisense ODNs did not show any pathological changes. However, in PAN, rats with massive proteinuria showed increased deposition of C3 and C5b-9 in tubules in antisense-treated kidneys, and histological assessment revealed more severe tubulointerstitial injury in antisense-treated animals compared with controls.

CONCLUSION

These results establish a pathogenic role for complement in leading to tubulointerstitial injury during proteinuria and, to our knowledge for the first time, show a protective role of a complement regulatory protein, Crry, in renal interstitial disease.

Clonal involvement of eosinophils in therapy-related myelodysplastic syndrome with eosinophilia, translocation t(1;7) and lung cancer

We report a therapy-related MDS (RAEB) patient with eosinophilia, unbalanced translocation der(7)t(1;7) (q12;q22) and lung cancer. We observed no increase in cytokine levels in serum or in the conditioned medium (CM) of peripheral T cells cultured with or without IL-2. When bone marrow (BM) cells were cultured with GM-CSF, IL-3 and SCF in a semisolid system, the colonies were exclusively eosinophilic. Cytogenetic analysis of the colony cells identified the same chromosome abnormality in all metaphases to that of BM cells. Suspension and clonogenic colony assay of BM cells cultured with various cytokines showed predominant eosinophilic growth and differentiation with GM-CSF, but not with the other cytokines examined. These findings, together with mild morphological abnormalities of eosinophils, indicate clonal involvement of eosinophils in the myelodysplastic syndrome (MDS) clone, and that the eosinophilia was derived from the neoplastic clone with the translocation and was not associated with the patient's lung cancer.

Translational motion of hydration water on protein surface

In the study of the role of the hydration water in the structure and function of biosystems, one of the major problems is the investigation of the dynamics of hydration water. For this purpose, many papers were reported about relaxation measurements of hydration water by 1HNMR. Most of them were concerned with rotational motion of hydration water. There were few papers dealing with translational motion of hydration water in rigid systems, such as unfrozen water and bound water of protein. The spin-echo or pulse gradient methods are useless in the study of such systems, whereas the self-diffusion coefficient D, the index of translational motion, can be estimated by the spin-locking method. This report is concerned with the study of the translational motion of unfrozen and bound water of solution and powder of protein, respectively, and the measuring of the values of D by spin-locking using of 1HNMR. The coefficient can be obtained by measuring the relaxation time T1 varying the locking power w1. For hydration monolayer in protein solution at -35 degrees C, D values of 10(-9)-10(-10) cm2/sec, and for monolayer in protein powder at room temperature, D values of 10(-10)-10(-11) cm2/sec were obtained. By heat denaturation of the protein, the values were slightly altered, though the rotational motion revealed by T1 measurement appeared not so affected. This difference might derive from the alteration of the protein surface by the unfolding of protein molecule due to the denaturation.(ABSTRACT TRUNCATED AT 250 WORDS)