Transferrin receptor (TfR) plays a major role in cellular iron uptake through binding and internalizing a carrier protein transferrin (Tf). We have cloned, sequenced, and mapped a human gene homologous to TfR, termed TfR2. Two transcripts were expressed from this gene: ␣ (ϳ2.9 kilobase pairs), and  (ϳ2.5 kilobase pairs). The predicted amino acid sequence revealed that the TfR2-␣ protein was a type II membrane protein and shared a 45% identity and 66% similarity in its extracellular domain with TfR. The TfR2- protein lacked the aminoterminal portion of the TfR2-␣ protein including the putative transmembrane domain. Northern blot analysis showed that the ␣ transcript was predominantly expressed in the liver. In addition, high expression occurred in K562, an erythromegakaryocytic cell line. To analyze the function of TfR2, Chinese hamster ovary TfR-deficient cells (CHO-TRVb cells) were stably transfected with FLAG-tagged TfR2-␣. These cells showed an increase in biotinylated Tf binding to the cell surface, which was competed by nonlabeled Tf, but not by lactoferrin. Also, these cells had a marked increase in Tfbound 55 Fe uptake. Taken together, TfR2-␣ may be a second transferrin receptor that can mediate cellular iron transport.
Objective.-A phase 2, double-blind, placebo-controlled study to evaluate the efficacy and safety of erenumab for the prevention of episodic migraine in Japanese patients was conducted.Background.-Previous global clinical studies have demonstrated the efficacy of erenumab in the prevention of migraine.Methods.-Patients were randomized to placebo or erenumab 28, 70, or 140 mg administered subcutaneously once per month for 6 months. The primary endpoint was change from baseline in mean monthly migraine days over months 4-6 of the double-blind treatment phase. Secondary endpoints included the proportion of patients achieving ≥50% reduction from baseline in mean monthly migraine days (≥50% response) and change from baseline in mean monthly acute migraine-specific medication treatment days (MSMD) and mean Headache Impact Test (HIT-6™) scores. Efficacy outcomes were also determined at months 1, 2, and 3.Results.-Four hundred and seventy five patients were randomized 2:1:2:2 to placebo and erenumab 28, 70, and 140 mg, respectively. Greater reductions in monthly migraine days were observed for erenumab vs placebo with differences of -1.25 (95% CI: -2.10 to -0.41; P = .004), -2.31 (95% CI: -3.00 to -1.62; P < .001), and -1.89 (95% CI: -2.58 to -1.20; P < .001) days for erenumab 28, 70, and 140 mg. The odds of having a ≥50% response were 3.2, 5.6, and 4.7 times greater for erenumab 28 mg (95% CI: 1.30-7.88; P = .009), 70 mg (95% CI: 2.60-12.06; P < .001), and 140 mg (95% CI: 2.24-9.99; P < .001) than for placebo. Greater reductions from baseline in mean acute monthly MSMD were observed for erenumab vs placebo with differences of -1.07 (95% CI: -1.80 to -0.35; P = .004), -2.07 (95% CI: -2.66 to -1.49; P < .001), and -2.04 (95% CI: -2.63 to -1.45; P < .001) days for erenumab 28, 70, and 140 mg. Erenumab 70 and 140 mg also resulted in greater improvements in HIT-6™ scores. The safety profile was similar across treatment groups. The most common adverse event was nasopharyngitis, which occurred in 29.4% of patients in the placebo group and 28.9%-33.3% of patients in the erenumab groups.Conclusion.-Monthly subcutaneous injections of erenumab 70 mg demonstrated statistically significant and numerically maximal efficacy with a favorable safety profile, suggesting that erenumab is a potential new therapy for migraine prevention in Japan.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
A nuclear criticality accident occurred in Japan on September 30, 1999, which resulted in severe exposure of three victims to mixed flux of neutrons and gamma-rays. Estimated average doses for the three victims were 5.4 Gy of neutrons and 8.5 Gy of gamma-rays for Patient A, 2.9 Gy of neutrons and 4.5 Gy of gamma-rays for Patient B, and 0.81 Gy of neutrons and 1.3 Gy of gamma-rays for Patient C. They then suffered the consequences of the effects of ionizing radiation resulting in acute radiation syndrome. In Patients A and B, bone marrow failure was so severe that they received haematopoietic stem cell transplantation. The graft initially took successfully in both patients, although in Patient B it was later taken over by his own haematopoietic cells. They also suffered from severe skin lesions, later exhibited gastrointestinal bleeding and eventually died of multiple organ failure 82 and 210 days after the accident, respectively. The survival of these patients beyond the period of agranulocytosis means that bone marrow failure per se caused by exposure to ionizing radiation may now be overcome. Patient C also developed bone marrow failure and was treated with granulocyte colony-stimulating factor as well as supportive care. He recovered without major complications and is now under periodical follow-up. Remarkably, during the prodromal phase, all the patients exhibited hypoxaemia, two of whom also showed interstitial oedema of the lungs. In Patient C these manifestations improved within a week. The circumstances of the accident and the initial medical treatment of the victims are described.
Adult T-cell leukemia (ATL) is associated with prior infection with human T-cell leukemia virus type I (HTLV-I). Twenty to 40 years often elapse from viral infection to overt ATL, suggesting that other genetic events must occur to produce frank leukemia. The p15 (MTS2) and p16 (CDKN2/MTS1) genes located on chromosome 9p have been implicated as candidate tumor-suppressor genes in several types of tumors. We examined for alterations of these genes in ATL using Southern blot and polymerase chain reaction-single-strand conformation polymorphism analyses. Both p15 and p16 genes were homozygously deleted in 4 of 23 acute/lymphomatous ATL (17%). An additional 3 (13%) and 4 (17%) acute/lymphomatous samples had hemizygous deletions in at least one exon of p15 and p16, respectively. One of 14 chronic ATL samples had a homozygously deleted p16 gene and another had a hemizygous deletion of p16. Neither homozygous nor hemizygous deletions of the p15 gene were found in chronic ATL. In total, 10 of 37 (27%) ATL samples had loss of the p15 and/or p16 genes. No point mutations of the p15 and p16 genes were found. The ATL patient with a homozygously deleted p16 in the chronic phase rapidly progressed to acute ATL and died within 6 months of the initial diagnosis. One instructive patient had no detectable deletion of the p15 and p16 genes during the chronic phase of ATL but had a homozygous deletions of both genes when she progressed to acute ATL. Our results suggest an association of p15/p16 deletions with development of acute ATL.
The protein p27KIP1 belongs to a recently identified family of proteins termed cyclin-dependent kinase inhibitors (CDKIs). These proteins play an important role in regulating cell-cycle progression and loss of their function has been implicated in tumorigenesis. Transforming growth factor beta (TGF-beta) may induce cell growth arrest through p27 activation. TGF-beta often loses its ability to arrest growth of transformed cells; this could potentially occur through a defect in p27. To determine the role of p27 in tumorigenesis, we examined its mutational status in 74 non-Hodgkin's lymphomas (NHLs) (52 of B-cell phenotype, 22 of T-cell phenotype), 5 lymphoma cell lines, and 42 adult T-cell leukemias/lymphomas (ATLs) using polymerase chain reaction- single strand conformational polymorphism (PCR-SSCP) and Southern blot analyses. A nonsense mutation (stop codon) that could result in expression of a truncated nonfunctional p27 protein was detected at codon 76 in one case of acute lymphomatous ATL, but not in matched normal tissues. Previously undescribed polymorphisms were also identified at codon 109 in the lymphomas and at codon 55 in the ATLs. Two homozygous deletions of the p27 gene were detected in one case of B- immunoblastic NHL and in one case of acute ATL by Southern blot hybridization. These results indicate that p27 gene alterations are rare events in NHLs and ATLs, but may play an important role in the pathogenesis of some hematologic malignancies.
Summary.To study the structural integrity of the cyclindependent kinase inhibitors known as INK4A (p16), INK4B (p15) and INK4C (p18) in multiple myeloma, we examined 20 primary myeloma samples (including one case of plasma cell leukaemia) using polymerase chain reaction-single strand conformation polymorphism, and 17 samples were examined by Southern blot analysis. The plasma cell leukaemia sample had homozygous deletions of the p15 and p16 genes (6%). One myeloma case had a p15 gene homozygous deletion (6%) with an intact p16 gene. This sample also had a p18 homozygous deletion, suggesting that the deletion of both genes may be important in either the development or progression of myeloma. No point mutations of these INK4 genes were found in the 20 samples. This is the first report that indicates that deletions of p15, p16 and p18 genes occur in some individuals with multiple myeloma (2/17 cases).
Initial symptoms/Acute radiation syndrome/Dose assessment/Criticality accidentA criticality accident occurred on September 30, 1999, at the uranium conversion plant in Tokai-mura (Tokai-village), Ibaraki Prefecture, Japan. When the criticality occurred, three workers saw a "blue-white glow," and a radiation monitor alarm was sounded. They were severely exposed to neutron and γ -ray irradiation, and subsequently developed acute radiation syndrome (ARS). One worker reported vomiting within minutes and loss of consciousness for 10 -20 seconds. This worker also had diarrhea an hour after the exposure. The other worker started to vomit almost an hour after the exposure. The three workers, including their supervisor, who had no symptoms at the time, were brought to the National Mito Hospital by ambulance. Because of the detection of γ -rays from their body surface by preliminary surveys and decreased numbers of lymphocytes in peripheral blood, they were transferred to the National Institute of Radiological Sciences (NIRS), which has been designated as a hospital responsible for radiation emergencies. Dose estimations for the three workers were performed by prodromal symptoms, serial changes of lymphocyte numbers, chromosomal analysis, and 24 Na activity. The results obtained from these methods were fairly consistent. Most of the data, such as the dose rate of radiation, its distribution, and the quality needed to evaluate the average dose, were not available when the decision for hematopoitic stem cell transplantation had to be made. Therefore, prodromal symptoms may be important in making decisions for therapeutic strategies, such as stem-cell transplantation in heavily exposed victims. S158 M. AKASHI ET AL.
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