Investigation of biomarkers to predict outcomes in allogeneic hematopoietic stem cell transplantation

BACKGROUND

Various biomarkers have been developed and evaluated to predict the prognosis and complications of allogeneic hematopoietic cell transplantation (HCT). Most previous studies conducted on different biomarkers evaluated single effects such as those associated with inflammation, immunology, iron metabolism, and nutrition, and only a few studies have comprehensively analyzed markers.

OBJECTIVE

The study aimed to survey comprehensive multiple markers prior to HCT and extract those that significantly predict the outcomes.

STUDY DESIGN

A prospective multicenter observational study was performed. (UMIN000013506) Patients undergoing HCT for hematologic diseases were consecutively enrolled. Besides the usual clinical biomarkers, serum samples for extra-clinical biomarkers were collected and cryopreserved before starting the conditioning regimen. A total of 32 candidate biomarkers were selected, 23 from hematology, biochemistry, immunology, nutrition, and iron metabolism, and 9 from composite markers. Based on the area under the curve (AUC) values for survival, promising biomarkers was extracted. Internal validation for these markers was applied based on bootstrap methods. Setting the cut-off values for them, log-rank test was applied and outcomes including overall survival (OS), relapse, and non-relapse mortality (NRM) were evaluated using multivariate analyses. Furthermore, detailed analysis including transplant-related complications and external validation were conducted focusing on C-reactive protein (CRP) to platelet (Plt) ratio.

RESULTS

A total of 152 patients with hematologic malignancies were enrolled from April 2014 to March 2017. CRP, soluble interleukin-2 receptor (IL2R), CRP to albumin (Alb) ratio, CRP to Plt ratio, Plt to IL2R ratio, and IL2R to Alb ratio were identified as promising markers. Internal validation successfully confirmed their reliability of AUC and multivariate analysis demonstrated the statistical significance between the higher and the lower markers. Above all, a higher CRP to Plt ratio was significantly associated with a lower OS (hazard ratio [HR] 2.77; 95% confidence interval [CI] 1.30-5.91; P = 0.008) and higher non-relapse mortality rates (HR 2.79; 95%CI 1.14-6.80; P = 0.024) at 180 days. Furthermore, univariate analysis showed that a higher CRP to Plt ratio was significantly associated with a higher incidence of sinusoidal obstructive syndrome (P < 0.001) and bloodstream infection (P = 0.027). An external validation test confirmed the significance of the CRP to Plt ratio for these outcomes.

CONCLUSION

The multicenter prospective observational study successfully identified significant biomarkers in patients with hematologic malignancies who received HCT. In particular, CRP to Plt ratio was identified as a novel and useful biomarker for predicting transplant outcomes. Further investigations are needed to validate the novel markers, analysis of the pathophysiology, and application to treatment settings other than HCT.

Monitoring SARS-CoV-2 Viral Load and CD4+ T-cell Count After ART in a Patient Diagnosed With AIDS Following SARS-CoV-2 Infection: A Case Report

We describe the case of a 36-year-old man diagnosed with human immunodeficiency virus (HIV) following prolonged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia. The patient had a complication of pneumocystis pneumonia. Upon initiating highly active antiretroviral therapy, we monitored HIV RNA levels, CD4+ T-cell count, SARS-CoV-2 viral load, and IgG antibodies against SARS-CoV-2. At 167 days post SARS-CoV-2 diagnosis, the patient's CD4+ T-cell count increased to 180 cells/μL. IgG antibodies against SARS-CoV-2 were undetectable despite a decreased SARS-CoV-2 viral load. HIV screening is necessary in cases of prolonged SARS-CoV-2 pneumonia or persistent SARS-CoV-2 shedding. When diagnosed with HIV infection, it is advisable to consider the possibility of pneumocystis pneumonia.

Monitoring mutant KRAS in plasma cell-free DNA can predict disease progression in a patient with multiple myeloma: A case report

BACKGROUND AND AIMS

Multiple myeloma (MM), a neoplasm of plasma cells (PCs), is a highly heterogeneous disease with multifocal dissemination throughout the body. Minimal residual disease (MRD) detected using PCs in bone marrow (BM) is important for MM management; however, frequent invasive examinations impose a significant burden on patients.

METHODS

Analysis using plasma cell-free DNA (cfDNA) might represent an alternative tool for disease monitoring. In this study, we observed the disease status in a patient with MM by examining the KRAS mutation allele frequency (MAF) in plasma cfDNA using digital PCR.

RESULTS

During treatment, the MAF was correlated with serum immunoglobulin A and free light chain-kappa levels. After the second autologous peripheral blood stem cell transplantation, the KRAS MAF became immediately positive after confirming MRD negativity using PCs from BM. Shortly thereafter, the patient experienced clinical relapse primarily involving bone lesions.

CONCLUSION

Mutant KRAS monitoring in cfDNA using serial blood collection might reflect the disease status more accurately than invasive BM examinations, especially in patients with MM whose primary lesions have extra-BM locations. It could also help predict treatment responses and outcomes.

A case of lymphoma mimicking infected internal iliac artery aneurysm

BACKGROUND

Malignant lymphoma rarely mimics an infected arterial aneurysm and a ruptured arterial aneurysm because of similar imaging findings, leading to misdiagnosis. The hematomas of ruptured aneurysms are radiologically difficult to distinguish from those of malignant lymphoma in emergency settings. Hence, a definitive diagnosis is crucial to avoid unnecessary surgery.

CASE PRESENTATION

A man in his 80s with hematuria and shock vital had right internal iliac artery aneurysm (IIAA) and perianeurysmal fluid retention, which appeared to be a ruptured or an infected aneurysm. Treatment was initiated for infected IIAA instead of for ruptured IIAA. Systemic inflammatory response syndrome developed, and the infectious sources were assessed. Pacemaker lead and urinary tract infections were identified and treated; however, blood pressure was unstable. The aneurysm was treated with endovascular aortic aneurysm repair following antibiotic therapy; however, fluid retention increased, and inflammatory status and hematuria deteriorated. Open surgical conversion was performed to manage the infected lesions. Although an iliopsoas abscess was detected during surgery and nephrectomy and ureterectomy were performed to control the hematuria, analysis of the removed tissues led to the pathological diagnosis of diffuse large B-cell lymphoma (DLBCL).

CONCLUSIONS

We encountered a case of DLBCL with imaging findings mimicking an infected internal iliac artery aneurysm, and definitive diagnosis was made more than 2 months after the initial examination. Definitively diagnosing malignant lymphoma around an iliac artery aneurysm based merely on symptoms and imaging findings is extremely difficult. Thus, histological examination should be actively performed in atypical infected aneurysms.

Ghrelin prevents lethality in a rat endotoxemic model through central effects on the vagal pathway and adenosine A2B signaling : Brain ghrelin and anti-septic action

Accumulating evidence suggest that ghrelin plays a role as an antiseptic peptide. The present study aimed to clarify whether the brain may be implicated ghrelin's antiseptic action. We examined the effect of brain ghrelin on survival in a novel endotoxemic model achieved by treating rats with lipopolysaccharide (LPS) and colchicine. The observation of survival stopped three days after chemicals' injection or at death. Intracisternal ghrelin dose-dependently reduced lethality in the endotoxemic model; meanwhile, neither intraperitoneal injection of ghrelin nor intracisternal des-acyl-ghrelin injection affected the mortality rate. The brain ghrelin-induced lethality reduction was significantly blocked by surgical vagotomy. Moreover, intracisternal injection of a ghrelin receptor antagonist blocked the improved survival achieved by intracisternal ghrelin injection or intravenous 2-deoxy-d-glucose administration. Intracisternal injection of an adenosine A2B receptor agonist reduced the lethality and the ghrelin-induced improvement of survival was blocked by adenosine A2B receptor antagonist. I addition, intracisternal ghrelin significantly blocked the colonic hyperpermeability produced by LPS and colchicine. These results suggest that ghrelin acts centrally to reduce endotoxemic lethality. Accordingly, activation of the vagal pathway and adenosine A2B receptors in the brain may be implicated in the ghrelin-induced increased survival. Since the efferent vagus nerve mediates anti-inflammatory mechanisms, we speculate that the vagal cholinergic anti-inflammatory pathway is implicated in the decreased septic lethality caused by brain ghrelin.

Centrally administered GLP-1 analogue improves intestinal barrier function through the brain orexin and the vagal pathway in rats

Leaky gut, an altered intestinal barrier function, has been described in many diseases such as irritable bowel syndrome (IBS). We have recently demonstrated that orexin in the brain blocked leaky gut in rats, suggesting that the brain plays a role in regulation of intestinal barrier function. In the present study, we tried to clarify whether GLP-1 acts centrally in the brain to regulate intestinal barrier function and its mechanism. Colonic permeability was estimated in vivo by quantifying the absorbed Evans blue in colonic tissue in rats. Intracisternal injection of GLP-1 analogue, liraglutide dose-dependently abolished increased colonic permeability in response to lipopolysaccharide. Either atropine or surgical vagotomy blocked the central GLP-1-induced improvement of colonic hyperpermeability. Intracisternal GLP-1 receptor antagonist, exendin (9-39) prevented the central GLP-1-induced blockade of colonic hyperpermeability. In addition, intracisternal injection of orexin receptor antagonist, SB-334867 blocked the GLP-1-induced improvement of intestinal barrier function. On the other hand, subcutaneous liraglutide also improved leaky gut but larger doses of liraglutide were needed to block it. In addition, neither atropine nor vagotomy blocked subcutaneous liraglutide-induced improvement of leaky gut, suggesting that central or peripheral GLP-1 system works separately to improve leaky gut in a vagal-dependent or independent manner, respectively. These results suggest that GLP-1 acts centrally in the brain to reduce colonic hyperpermeability. Brain orexin signaling and the vagal cholinergic pathway play a vital role in the process. We would therefore suggest that activation of central GLP-1 signaling may be useful for leaky gut-related diseases such as IBS.

[Successful rituximab treatment of TAFRO syndrome refractory to glucocorticoids and tocilizumab]

A 53-year-old man was presented with fever, eyelid edema, and thrombocytopenia. Based on examination outcomes, he was diagnosed with immune thrombocytopenia. He was prescribed prednisolone (PSL) at 0.5 mg/kg/day; subsequently, his platelet count improved and fever improved. PSL dose was tapered and stopped without relapse. However, 1 month later, the patient presented to our hospital with fever, generalized edema, thrombocytopenia, and acute renal failure. Computed tomography revealed multiple lymphadenopathies, hepatomegaly, pleural effusion, and ascites. Bone marrow biopsy indicated reticulin fibrosis, and lymph node biopsy revealed mixed-type Castleman disease. Based on these findings, he was diagnosed with grade 5 TAFRO syndrome (very severe). Steroid pulse therapy and tocilizumab were ineffective in improving his condition. Therefore, rituximab was administered instead of tocilizumab, and his condition eventually improved. The optimal treatment for TAFRO syndrome is yet to be established. If tocilizumab is ineffective as the second-line treatment, then rituximab might be effective.

Late-onset posttransplant Epstein-Barr virusrelated lymphoproliferative disease after cord blood transplantation for chronic active Epstein Barr virus infection: A case report

INTRODUCTION

Posttransplant lymphoproliferative disease (PTLD) is a critical complication of hematopoietic stem cell transplantation (HSCT). PTLD is classified into early and late-onset PTLDs. In post-HSCT patients, late-onset PTLD is rare, particularly PTLD after HSCT for Epstein-Barr virus (EBV)-related lymphoproliferative disease. Here, we report the case of a patient diagnosed with late-onset EBV-related hemophagocytic lymphohistiocytosis (HLH), that of PTLD, after HSCT for chronic active EBV infection (CAEBV), that of EBV related lymphoproliferative disease, probably because of EBV reactivation.

PATIENT CONCERNS AND DIAGNOSIS

A 22-year-old woman with abdominal fullness visited our hospital. Blood examination showed pancytopenia with atypical lymphocytes, liver dysfunction, and elevated lactate dehydrogenase level. In contrast, bone marrow aspiration showed slight hemophagocytosis with increased natural-killer cells (NK cells). As serum antibodies against EBV were atypical, we calculated the EBV-DNA level in peripheral blood and this level was significantly high. EBV was infected with NK cells, and EBV's monoclonality in NK cells was confirmed. Thus, the patient was diagnosed with CAEBV.

INTERVENTIONS AND OUTCOMES

The patient received chemotherapy and cord blood cell transplantation (CBT); CAEBV was well controlled. Approximately 6years from CBT for CAEBV, she visited our hospital because of fever. Blood examination revealed pancytopenia with atypical lymphocytes, liver dysfunction, and elevated lactate dehydrogenase level. In contrast, bone marrow aspiration showed hemophagocytosis with increased B and T cell counts without increased NK cell count. Additionally, serum antibody titers against EBV were atypical, and the EBV-DNA level in the peripheral blood was high. EBV was infected with only B cells, and EBV's monoclonality was confirmed. A more detailed analysis indicated that EBV-specific cytotoxic T lymphocytes were inactive. Therefore, she was diagnosed with late-onset EBV-related HLH. She received extensive treatment, but EBV-related HLH did not improve. Finally, she died about 3 weeks after diagnosis.

CONCLUSION

PTLD, including HLH, is a life-threatening complication after transplantation, including HSCT. To our knowledge, this is the first case of late-onset EBV-related HLH after CBT for CAEBV. Late-onset PTLD has an indolent clinical course, but our patient's disease course was extremely aggressive. Therefore, late-onset EBV-related PTLD may be life-threatening.

A stealth antigen SPESP1, which is epigenetically silenced in tumors, is a suitable target for cancer immunotherapy

Recent studies have revealed that tumor cells decrease their immunogenicity by epigenetically repressing the expression of highly immunogenic antigens to survive in immunocompetent hosts. We hypothesized that these epigenetically hidden “stealth” antigens should be favorable targets for cancer immunotherapy due to their high immunogenicity. To identify these stealth antigens, we treated human lung cell line A549 with DNA methyltransferase inhibitor 5‐aza‐2′‐deoxycytidine (5Aza) and its prodrug guadecitabine for 3 d in vitro and screened it using cDNA microarray analysis. We found that the gene encoding sperm equatorial segment protein 1 (SPESP1) was re‐expressed in cell lines including solid tumors and leukemias treated with 5Aza, although SPESP1 was not detected in untreated tumor cell lines. Using normal human tissue cDNA panels, we demonstrated that SPESP1 was not detected in normal human tissue except for testis and placenta. Moreover, we found using immunohistochemistry SPESP1 re‐expression in xenografts in BALB/c‐nu/nu mice that received 5Aza treatment. To assess the antigenicity of SPESP1, we stimulated human CD4⁺ T‐cells with a SPESP1‐derived peptide designed using a computer algorithm. After repetitive stimulation, SPESP1‐specific helper T‐cells were obtained; these cells produced interferon‐γ against HLA‐matched tumor cell lines treated with 5Aza. We also detected SPESP1 expression in freshly collected tumor cells derived from patients with acute myeloid leukemia or lung cancer. In conclusion, SPESP1 can be classified as a stealth antigen, a molecule encoded by a gene that is epigenetically silenced in tumor cells but serves as a highly immunogenic antigen suitable for cancer immunotherapy.

Acquired hemophilia A associated with Epstein-Barr-virus-associated T/natural killer-cell lymphoproliferative disease: A case report

INTRODUCTION

Acquired hemophilia A (AHA) is a rare bleeding disorder caused by autoantibodies against factor VIII (FVIII). Hematological malignancies, especially lymphoid malignancies, are known to be underlying causes of AHA; however, thus far, there is no report of AHA associated with Epstein-Barr-virus-associated T/natural killer-cell lymphoproliferative disease (EBV-T/NK-LPD). Here, we present a case of AHA that developed during treatment for EBV-T/NK-LPD.

HISTORY

A 69-year-old man visited our hospital because of general fatigue. Blood examination showed pancytopenia, and computed tomography revealed whole-body lymphadenopathy, but there were no findings indicating hematological malignancy from bone marrow aspiration and cervical lymph node biopsy. The level of EBV DNA in peripheral blood was extremely high, and he was diagnosed with EBV-T/NK-LPD. EBV-T/NK-LPD improved with prednisolone (PSL) administration. Seventeen months after starting treatment, the patient complained of back and right leg pain. At that time, he had been treated with low-dose PSL, and EBV-T/NK-LPD was well controlled. Imaging revealed hematoma of the right iliopsoas muscle. Prolonged activated partial thromboplastin time (APTT) was the only abnormal finding in a screening coagulation test. FVIII coagulant activity was below detection limit, and FVIII inhibitor level was increased. From these results, he was diagnosed with AHA.A higher dose of PSL was administered, and, after 1 month of treatment, FVIII activity gradually increased, and FVIII inhibitor level became undetectable. APTT also normalized, and complete remission was achieved and maintained for 13 months with low-dose PSL. During treatment, EBV-T/NK-LPD was well controlled.

CONCLUSION

It is speculated that proliferating lymphocytes interfere with normal immune functions and that abnormal autoantibodies are produced from those lymphocytes in patients with LPD. Therefore, we speculate that EBV-infected and proliferating monoclonal NK cells might have modulated the immune system and produced autoantibodies against FVIII, thus causing AHA in this patient with EBV-T/NK-LPD.

Novel automated measuring system for evaluating labile plasma iron in serum

Background

As the saturation of transferrin by iron in the serum is approximately 30%, iron loaded to the blood can bind to transferrin not bearing iron. Nevertheless, prolonged iron influx finally results in full transferrin saturation, and iron not bound to transferrin will appear in the serum; this iron is known as non-transferrin-bound iron (NTBI). NTBI damages organs through the production of free radicals. Previously, we established an automated quantification system for NTBI; however, measuring labile plasma iron, which is considered as a highly redox-active component of NTBI, should be a better prognostic factor in iron-overloaded patients.

Methods

We designed and developed a novel system for evaluating labile plasma iron utilizing the Trinder reaction. Automated system was utilized because the previously reported methods for labile plasma iron are intricate and the introduction to the clinical stage has been challenging. Validations such as the contribution of serum proteins and metal ions for this system were evaluated using human serum samples.

Results

We confirmed that our novel system can evaluate labile plasma iron utilizing Trinder reaction and the oxidative potential of ceruloplasmin in the serum. This system was also confirmed to be clinically practical. Metals other than iron did not influence this system. We observed that samples with high NTBI did not always exhibit high labile plasma iron and vice versa, highlighting the necessity of labile plasma iron quantification in evaluating the toxicity of NTBI.

Conclusions

Our novel system should contribute to fundamental and clinical research because it can measure labile plasma iron using the high-throughput automated analyser.

Pseudogout Attack after Pegfilgrastim Administration in Anaplastic Large Cell Lymphoma

A 67-year-old man with relapsed anaplastic large cell lymphoma received salvage chemotherapy, and pegfilgrastim was used to prevent febrile neutropenia. On day 18 of chemotherapy, he developed a pseudogout attack. Although the first symptoms improved, another pseudogout attack occurred when he received the second course of chemotherapy and pegfilgrastim. Filgrastim was then used for the third course of chemotherapy, and a pseudogout attack did not occur. The serum granulocyte-stimulating factor (G-CSF) level was extremely elevated only when pegfilgrastim was used, suggesting a relationship between pseudogout and G-CSF. Pseudogout should be recognized as an adverse effect of pegfilgrastim.

Angioimmunoblastic T-cell lymphoma and hypereosinophilic syndrome with FIP1L1/PDGFRA fusion gene effectively treated with imatinib: A case report

RATIONALE

Hypereosinophilic syndrome (HES) is a rare disorder characterized by hypereosinophilia and organ damage. Some cases of HES are caused by the FIP1L1/PDGFRA fusion gene and respond to imatinib. FIP1L1/PDGFRA-positive HES occasionally evolves into chronic eosinophilic leukemia or into another form of myeloproliferative neoplasm; however, the development of a malignant lymphoma is very rare. We present a rare case of angioimmunoblastic T-cell lymphoma (AITL) and HES with the FIP1L1/PDGFRA gene rearrangement.

PATIENT CONCERNS

A man in his 30s presented to our hospital with fever, hypereosinophilia, widespread lymphadenopathy, and splenomegaly. Laboratory tests showed hypereosinophilia, increased soluble interleukin-2 receptor, and increased vitamin B12. Positron-emission tomography with F fluorodeoxyglucose (FDG) showed positive FDG uptake in multiple enlarged lymph nodes throughout the body and the red bone marrow. A bone-marrow biopsy showed hypereosinophilia without dysplasia and an increased number of blasts. The FIP1L1/PDGFRA fusion gene was positive upon fluorescence in situ hybridization (FISH) analysis of the peripheral blood. Furthermore, biopsy of a lymph node from the neck revealed restiform hyperplasia of capillary vessels, with small lymphoma cells arranged around the capillaries. Lymphoma cells were positive for CD3, CD4, and CD10, and negative for CD20. Lymphoma cells were also positive for the FIP1L1/PDGFRA fusion gene by FISH analysis.

DIAGNOSES

From these findings, the patient was diagnosed with HES and AITL with FIP1L1/PDGFRA.

INTERVENTIONS

After the diagnosis, corticosteroid was administered but was ineffective. Imatinib was then administered.

OUTCOMES

Imatinib was very effective for treating HES and AITL, and complete remission was achieved in both.

LESSONS

This report presents the first case in which the FIP1L1/PDGFRA fusion gene was positive both in peripheral blood and lymph nodes, implying the possibility that the tumor cells acquired the FIP1L1/PDGFRA fusion gene in the early stage of hematopoietic progenitor cell developments. Imatinib was very effective in treating both HES and lymphoma, suggesting that the FIP1L1/PDGFRA fusion gene plays a key role in the pathogenesis of both HES and lymphoma.

[Evaluation of Basic Performance of "Point Strip ferritin-3000" for Simple and Rapid Quantification of Serum Ferritin]

Serum ferritin is an excellent marker for total iron content in the body and is essential for the diagnosis of iron deficiency or iron overload. Recently, a simple and rapid method, which utilizes immunochromatography for the quantification of serum ferritin, was developed. However, the range of measurement in previous reagents was limited (10-500 ng/mL). This range is rather narrow and is not fully helpful for the diagnosis of iron overload which sometimes occurs as a result of prolonged transfusions, or for monitoring iron contents during iron chelation therapy against iron overload. In the present study we evaluated the basic performance of the newly developed "Point Strip ferritin-3000", which can measure serum ferritin in the range of 300-3,000 ng/mL. Coefficient of variation (CV) s of within and inter-day assays were in the ranges of 7.3-11.1% and 2.1-5.2%, respectively. Using 87 serum samples obtained from the patients with written informed consents, the correlation coefficient was calculated to be 0.93 compared to the control method. In addition, the quantification of serum ferritin by "Point Strip ferritin-3000" was not influenced by bilirubin, hemoglobin, chyle, rheumatoid factor, or ascorbic acid. From our data, "Point Strip ferritin-3000" is reliable reagent in the range of 300-3,000 ng/mL, and is therefore considered to be useful for the diagnosis of iron overload, as well as for monitoring iron contents during iron chelation therapy. In addition, this quantification method can be easily performed using a small desktop equipment without any special technique, making this system applicable for epidemiological surveys and clinical studies.

Non-transferrin-bound iron assay system utilizing a conventional automated analyzer

BACKGROUND

Iron is an essential metal in the body, but its excessive accumulation causes damage in various organs through free radical production. Iron homeostasis is therefore tightly regulated. However, when iron balance collapses, such as in prolonged transfusion, transferrin (Tf) is fully saturated and non-Tf-bound iron (NTBI) appears in the serum. Monitoring serum NTBI levels is therefore crucial in the assessment of the clinical status of patients with iron overload, since NTBI is associated with cellular and organ damage. Several methods for NTBI determination have been reported, but these are extremely complicated and very few laboratories can quantify NTBI at present.

METHODS

We established a novel assay system utilizing automated analyzers that are widely used in clinical laboratories for diagnostic testing. In this assay, NTBI is chelated by nitrilotriacetic acid (NTA), after which the iron is reduced and transferred to nitroso-PSAP, a chromogen.

RESULTS

The assay shows excellent linearity, reproducibility, and compatibility with HPLC, one of the most reliable conventional methods for NTBI quantification.

CONCLUSIONS

Our novel method for NTBI measurement is high-throughput and may be a useful and powerful tool in the study of the physiological and clinical importance of NTBI.

Screening of As-accumulating plants using a foliar application and a native accumulation of As

The discovery of novel accumulating plants is useful for efficient phytoremediation due to the demands of various conditions of impacted sites such as land use, soil properties, concentration of pollutants, and climate. In the present study, we investigated foliar application or a field with highly bioavailable arsenic (As) to screen As-accumulating plants. Plants grown in the downstream of a hot springs area were analyzed for native As accumulation and As foliar application, and the rhizosphere soils were collected. The water-soluble As in the rhizosphere soils had a high average, 144 microg/kg, whereas total As was similar to normal soil in Japan. Among 34 herbaceous plants and 17 woody plants, Chelidonium majus var. asiaticum accumulated a relatively high As level, 8.07 mg/kg DW (93.6% of As added), that was not revealed by native accumulation. In a further pot experiment, C. majus accumulated a moderately high As level (314 mg/kg DW) in the roots but not in the shoot (30.1 mg/kg DW), and exhibited a low transfer factor (TF = 0.096). Thus, a foliar application would be a simple and high-throughput method to screen plants that accumulate and tolerate As. C. majus would be useful as a tool for phytostabilization of As.

Development of POEMS syndrome after an initial manifestation of solitary plasmacytoma

A 44-year-old male was admitted for numbness in the left arm. CT showed a tumor impacting on the spinal cord with an adjacent thoracic vertebral osteosclerotic lesion. The histopathology of the tumor showed diffuse proliferation of atypical plasma cells with expressed vascular endothelial growth factor (VEGF), which is a known etiological factor in POEMS syndrome. Though serum VEGF (sVEGF) level was elevated, a diagnosis of solitary plasmacytoma with an osteosclerotic lesion was made as the patient presented no polyneuropathy, organomegaly, endocrinopathy, or skin changes. The patient experienced muscle weakness of the lower limbs and skin pigmentation/hemangioma one year after irradiation of the osteosclerotic lesion. Laboratory tests revealed hypothyroidism, hyperglycemia, serum monoclonal gammopathy, further elevation of sVEGF, and increased atypical bone marrow plasma cells. CT imaging showed splenomegaly, and a nerve conduction test revealed demyelinating motor peripheral neuropathy. The patient was therefore diagnosed with POEMS syndrome. Plasmacytoma is very rare as an initial manifestation of POEMS syndrome. Patients presenting with plasmacytoma with an osteosclerotic lesion should be carefully observed and evaluated for the expression of sVEGF and development of POEMS syndrome, as most bone plasmacytomas in POEMS syndrome patients are reported to be osteosclerotic. This is to our knowledge the first case of osteosclerotic plasmacytoma that progressed to POEMS syndrome, with an increase of sVEGF.

Apoptosis in skin pigment cells of the medaka, Oryzias latipes (Teleostei), during long-term chromatic adaptation: the role of sympathetic innervation

Many teleost fish can adapt their body color to a background color by changing the morphology and density of their skin pigment cells. Melanophore density in fish skin decreases during long-term adaptation to a white background. Although cell death, especially apoptosis, is thought to be involved in these morphological changes, there are no data clearly supporting this mechanism. Using medaka fish, Oryzias latipes, we observed that, on a white background, melanophore size was reduced first and this was followed by a decrease in melanophore density caused by gradual cell death. The process of cell death included loss of cell activity, cell fragmentation, phagocytosis of the fragments, and clearance via the epidermis. Apoptosis was assessed by the appearance of phosphatidylserine on the cell surface of melanophores that had lost motile activity, and DNA fragments involved in cell fragmentation were detected by the TUNEL (TDT-mediated dUTP-biotin nick end-labeling) assay. However, when chemically denervated fish were used, although melanophore size was reduced as expected, cell death was suppressed even on a white background. In skin tissue culture, apoptosis in melanophores was stimulated significantly by norepinephrine, but not by melanin-concentrating hormone. These results indicate that melanophore density decreases by apoptosis, and suggest that sympathetic innervation has an important role in the regulation of apoptosis in melanophores. In analogous fashion, leucophores showed a significant decrease in density with an increase of cell death on a black background. We suggest that apoptosis regulates the balance of pigment cells in the skin of medaka fish to adapt their body color to a particular background.

Acyloxycoumarinylmethyl-caged cAMP, the photolabile and membrane-permeable derivative of cAMP that effectively stimulates pigment-dispersion response of melanophores

Two acyloxycoumarinylmethyl-caged cAMPs (ACM- and PCM-cAMP) have been synthesized using a silver (I) oxide promoted method. Introduction of the acyloxy group to the 7-position on the coumarin ring not only enhanced the membrane permeability but diminished the photolability of the coumarin-cage. Because intracellular enzymatic hydrolysis of the 7-acyloxy group would produce the 7-hydroxy moiety which is more hydrophilic and photolabile, application of acyloxycoumarinylmethyl-caged cAMPs in biological studies would be expected to be efficient. Thus, the effect of extracellularly applied ACM- and PCM-cAMP had been investigated using the motile response of fish melanophores. After irradiation, a significant enhancement in the motility responses was observed. The observed magnitudes of the dispersions are comparable to that of Bt2cAMP/AM which is known as a membrane permeable cAMP derivative.