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T Arima

Publications and source records attributed to T Arima.

At least 55 records · Page 3Linked to original sources
PubMed2001

Prognostic significance of multidrug resistance protein in adult T-cell leukemia.

The response of adult T-cell leukemia (ATL) to chemotherapy is poor, and a major obstacle to successful treatment is intrinsic or acquired drug resistance. To determine the clinical significance of multidrug resistance protein (MRP) 1 in ATL, we studied MRP1 expression and its association with clinical outcome. The expression of MRP1 mRNA in leukemia cells from 48 ATL patients was studied by slot blot analysis. The expression level of MRP1 mRNA in chronic-type ATL was significantly higher than that in lymphoma-type ATL (P = 0.033). There was no correlation between MRP1 expression and age, gender, WBC count, LDH, hypercalcemia, blood urea nitrogen, or performance status. However, the expression of MRP1 mRNA correlated only with peripheral blood abnormal lymphocyte counts (P = 0.008). The transporting activity of MRP1 was assessed using membrane vesicles. Membrane vesicles prepared from ATL cells with high expression of MRP1 mRNA showed a higher ATP-dependent leukotriene C(4) uptake than did those with low expression of MRP1 mRNA. This uptake was almost completely inhibited by LTD(4) antagonists ONO-1078 and MK571. In acute- and lymphoma-type ATL, high expression of MRP1 mRNA at diagnosis correlated with shorter survival, and Cox regression analysis revealed that MRP1 expression was an independent prognostic factor. These findings suggest that functionally active MRP1 is expressed in some ATL cells and that it is involved in drug resistance and has a possible causal relationship with poor prognosis in ATL. Multidrug resistance-reversing agents, such as ONO-1078 and MK571, that directly interact and inhibit the transporting activity of MRP1 may be useful for treating ATL patients.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

[Collateral blood flow showing dissection-like filling defect on coronary arteriography: a case report].

A 51-year-old man presented under a diagnosis of angina pectoris manifesting as exertional chest pain. First coronary angiography showed severe stenosis with ulceration and spontaneous dissection at the proximal right coronary artery and linear dissection-like filling defects extending to the distal right coronary artery. After about 3 months, repeat coronary angiography showed the previously observed stenosis with unclear dissection, and better developed collaterals from the left coronary artery to the right coronary artery showing the linear dissection-like filling defects. The bilateral coronary angiography did not clearly show filling defects. This phenomenon suggested that the collateral flows were related to filling of the defects. Intravascular ultrasonic imaging demonstrated severe atherosclerotic lesions at the proximal right coronary artery, but no dissection in the distal right coronary artery. Percutaneous transluminal coronary angioplasty for the stenosis was performed successfully with a stent. Coronary angiography after the angioplasty showed no collaterals, and the right ventricular branch appeared, suggesting that the linear dissection-like filling defects extending to the distal right coronary artery were due to the collateral flows. Filling defects extending distal to a severe stenosis must be distinguished carefully from coronary dissection.

Angioplasty, Balloon, Coronary↗
PubMed2000

A novel imprinted gene, HYMAI, is located within an imprinted domain on human chromosome 6 containing ZAC.

Transient neonatal diabetes mellitus (TNDM) is a rare disease characterized by intrauterine growth retardation, dehydration, and failure to thrive due to a lack of normal insulin secretion. This disease is associated with paternal uniparental disomy or paternal duplication of chromosome 6, suggesting that the causative gene(s) for TNDM is imprinted. Recently, Gardner et al. (1999, J. Med. Genet. 36: 192-196) proposed that a candidate gene for TNDM lies within chromosome 6q24.1-q24.3. To find human imprinted genes, we performed a database search for EST sequences that mapped to this region, followed by RT-PCR analysis using monochromosomal hybrid cells with a human chromosome 6 of defined parental origin. Here we report the identification of a novel imprinted gene, HYMAI. This gene exhibits differential DNA methylation between the two parental alleles at an adjacent CpG island and is expressed only from the paternal chromosome. A previously characterized imprinted gene, ZAC/LOT1, is located 70 kb downstream of HYMAI and is also expressed only from the paternal allele. In the pancreas, both genes are moderately expressed. HYMAI and ZAC/LOT1 are therefore candidate genes involved in TNDM. Furthermore, the human chromosome 6q24 region is syntenic to mouse chromosome 10 and represents a novel imprinted domain.

Alleles↗
PubMed2000

The cell cycle control gene ZAC/PLAGL1 is imprinted--a strong candidate gene for transient neonatal diabetes.

We describe a screen for new imprinted human genes, and the identification in this way of ZAC (zinc finger protein which regulates apoptosis and cell cycle arrest)/ PLAGL1 (pleomorphicadenoma of the salivary gland gene like 1) as a strong candidate gene for transient neonatal diabetes mellitus (TNDM). To screen for imprinted genes, we compared parthenogenetic DNA from the chimeric patient FD and androgenetic DNA from hydatidiform mole, using restriction landmark genome scanning for methylation. This resulted in identification of two novel imprinted loci, one of which (NV149) we mapped to the TNDM region of 6q24. From analysis of the corresponding genomic region, it was determined that NV149 lies approximately 60 kb upstream of the ZAC / PLAGL1 gene. RT-PCR analysis was used to confirm that this ZAC / PLAGL1 is expressed only from the paternal allele in a variety of tissues. TNDM is known to result from upregulation of a paternally expressed gene on chromosome 6q24. The paternal expression, map position and known biological properties of ZAC / PLAGL1 make it highly likely that it is the TNDM gene. In particular, ZAC / PLAGL1 is a transcriptional regulator of the type 1 receptor for pituitary adenylate cyclase-activating polypeptide, which is the most potent known insulin secretagog and an important mediator of autocrine control of insulin secretion in the pancreatic islet.

Cell Cycle↗
PubMed2000

The kinetics of tolerance induction by nondepleting anti-CD4 monoclonal antibody (RIB 5/2) plus intravenous donor alloantigen administration.

BACKGROUND: CD4+ T cells play an essential role in allograft rejection. The monoclonal anti-rat CD4 antibody, RIB 5/2, has been shown to modulate the CD4 glycoprotein without eliminating the recipient T cells. We have successfully induced tolerance to rat heart allografts by recipient pretreatment with a single dose of RIB 5/2 plus intravenous administration of donor splenocytes. In this study, we explored whether this potent regimen could induce tolerance to the more resistant kidney and skin allografts. Furthermore, we examined the kinetics and requirements for tolerance to be met by a single dose of RIB 5/2 plus i.v. alloantigen. METHODS: The efficacy of a single i.p. dose of 20 mg/kg RIB 5/2 plus i.v. donor antigen (25x10(6) splenocyte) pretreatment 0, 21, or 40 days before receipt of an MHC-mismatched Lewis (RT1l) to Buffalo (RT1b) rat cardiac, renal, or skin allograft was studied. Another group of Buffalo recipients treated with RIB 5/2 plus an i.v. alloantigen +/-thymectomy received kidney transplants after 40 days. Attempts to prevent tolerance used interleukin-2 or prior sensitization. Mixed lymphocyte cultures, cytotoxic assays, and precursor frequencies of helper and cytotoxic cells, by limiting dilution analysis, serially measured in vitro cell-mediated immunity. RESULTS: RIB 5/2 administration combined with i.v. alloantigen 21 days before induced tolerance to heart and kidney allografts but did not prolong skin graft survival. In contrast, kidney allografts delayed for 40 days after pretreatment were acutely rejected and survival was not affected by the thymectomy. MLC, CTL, and pTH, and pCTL precursor frequencies from recipients of long-term grafts were specifically suppressed to donor, but not third party, alloantigen. CONCLUSION: A single dose of the nondepleting anti-CD4 monoclonal antibody, RIB 5/2, plus i.v. alloantigen is a potent inducer of tolerance to heart and kidney, but not skin, allografts. The RIB 5/2-induced donor unresponsiveness to a delayed kidney or cardiac allograft is time dependent but can be prolonged if specific alloantigen is present. Suppression of cell-mediated allo-immune responsiveness correlates with allograft acceptance.

Adoptive Transfer↗
PubMed2000

Pericardial cyst in a child treated with video-assisted thoracoscopic surgery.

UNLABELLED: A pericardial cyst is a rare condition in childhood. We report on a 10-year-old girl who presented with an intrathoracic mass detected on a chest X-ray performed during a routine medical examination. She had no symptoms and a physical examination revealed no abnormalities. Ultrasonography, computed tomography and magnetic resonance imaging showed a multiloculated cystic mass in the right upper thorax. The cyst was resected using a thoracoscopic procedure. Histologically, the findings were consistent with a pericardial cyst. Thoracoscopic surgery was an effective surgical technique even for such a young patient and the results successfully reduced the morbidity. CONCLUSION: A pericardial cyst, a rare condition in childhood, was treated successfully by video-assisted thoracoscopic surgery.

Child↗
PubMed2000

Establishment and characterization of a new human megakaryoblastic cell line (SET-2) that spontaneously matures to megakaryocytes and produces platelet-like particles.

A new factor-independent megakaryoblastic cell line, designated SET-2, was established from the peripheral blood of a patient with leukemic transformation of essential thrombocythemia (ET). SET-2 expressed CD 4, 7, 13, 33, 34, 36, 38, 41, 61, 71, 117, 126, 130 and c-mpl. In addition, it spontaneously produced numerous platelet-like particles in liquid culture. These particles were shown to be the same size as normal platelets, and to express CD 36, 38, 41, 61 and 71. Proliferation of SET-2 was not influenced by thrombopoietin (TPO) and other hemopoietic cytokines. SET-2 was found to express the platelet-specific proteins such as platelet factor 4 and beta-thromboglobulin. The levels of expression were not altered by TPO. SET-2 also secreted interleukin-6 into the supernatants, as well as normal megakaryocytes. These results suggest that SET-2 spontaneously matures to megakaryocytes and produces platelet-like particles. These findings indicate that SET-2 may be useful for investigating the proliferation and differentiation mechanisms of leukemia cells and the role of c-mpl on megakaryoblasts, megakaryocytes, and platelets in ET. Leukemia (2000) 14, 142-152.

Aged↗
PubMed2000

EMG-force relationships are influenced by experimental jaw-muscle pain.

The bite force at different levels and the corresponding electromyographic (EMG) activity of the masseter and anterior temporalis muscles were recorded in 12 healthy subjects in order to evaluate the modulation of EMG-force curves by a standardized painful stimulus. Hypertonic saline (5%) was infused into the right masseter muscle for up to 15 min to induce pain. The pain intensity was scored continuously by the subjects on a 10-cm visual analogue scale (VAS). Subjects were asked to bite on a force transducer at the maximum voluntary bite force (MVBF). They were then asked to bite at submaximum levels of 12, 25, 37, 50, 67, 75 and 87% of MVBF. The biting was performed in three different positions (right first molar, left first molar and incisor) before, during and after infusion. Hypertonic saline caused moderate pain during infusion (mean VAS +/- s.e.m. = 6.5+/-0.5 cm). Both the MVBF and the maximum EMG activity in the right masseter and the left anterior temporalis muscles were significantly decreased during muscle pain when the subjects bit on the painful side. The EMG-force curves could be fit by linear relationships. The slope of the curve became less steep in the right masseter muscle during and after painful biting in every position. The results suggest that tonic saline-induced jaw-muscle pain is able to modulate the motor unit recruitment pattern of the jaw-closing muscles on the painful side. The main effect of pain in this experiment was an inhibition of static EMG activity.

Adult↗
PubMed2000

Left atrial diverticulum associated with severe mitral regurgitation.

Diverticulum of the atrium is a rare and controversial clinical entity, and in the present case a left atrial diverticulum was associated with severe mitral regurgitation (MR). A 68-year-old female with the diagnosis of MR was referred for further cardiac evaluation. Echocardiography revealed severe MR and an accessory cavity behind an enlarged left atrium. She underwent surgical valve replacement, but excision of the diverticulum was not done because its rupture seemed unlikely. A follow-up computed tomography performed 8 months postoperatively demonstrated disappearance of the diverticulum. The etiology of this atrial diverticulum is not clear, but the patient's MR may have played a role in its development.

Aged↗
PubMed2000

Toxic shock-like syndrome caused by T serotype B3264 streptococcus.

A 45-year-old woman was transferred from a local hospital to our hospital because of shock-like manifestations in addition to septic polyarthritis and necrotizing cellulitis of the left leg. Since Streptococcus pyogenes was isolated from the blood culture examined one day before admission, the diagnosis of streptococcal toxic shock-like syndrome (TSLS) was made. Antibiotic treatment together with supportive care started at the time of admission, resulting in clinical improvement, although poststreptococcal acute glomerulonephritis occurred during the period. TSLS is a life-threatening disease, but early recognition of the disease and prompt initiation of appropriate treatment may lead to successful outcome.

Anti-Bacterial Agents↗
PubMed2000

A novel mouse model of Graves' disease: implications for a role of aberrant MHC class II expression in its pathogenesis.

Mice immunized with fibroblasts expressing an MHC class II molecule and human thyrotropin receptor (TSHR), but not either alone, develop major features characteristic of Graves' disease (GD), such as thyroid-stimulating autoantibodies directed against TSHR, increased serum thyroid hormone levels, and enlarged thyroid glands. The results indicate the need for the simultaneous expression of a class II molecule and the TSHR on the surface of the fibroblasts to develop stimulating anti-TSHR antibodies and full-blown GD in our model. A T cell line established from a mouse with hyperthyroidism proliferates in response to fibroblasts expressing a class II molecule and TSHR, but not to the fibroblasts expressing only TSHR, indicating that the class II molecules on the fibroblasts present TSHR-derived peptide(s) to T cells. These results strongly suggest that the acquisition of antigen-presenting ability by thyrocytes can lead to the induction or progression of GD. We identified a T cell epitope of TSHR by the proliferative response of spleen cells from mice immunized with fibroblasts expressing a class II molecule and TSHR to 80 overlapping peptides spanning the extracellular domain of human TSHR. The identification of a major T cell epitope provides an important clue to a novel therapy of GD.

Animals↗
PubMed2000

Arsenic trioxide and the growth of human T-cell leukemia virus type I infected T-cell lines.

A novel therapeutic potential for acute promyelocytic leukemia using arsenic trioxide (As(2) O(3) ) has been reported. Recent in vitro studies demonstrated that As(2) O(3) effectively inhibits the growth of some cell lines derived from patients with malignant lymphoma, chronic lymphocytic leukemia and multiple myeloma. Adult T-cell leukemia (ATL) is an aggressive neoplasm of mature T-cell origin caused by human T-cell leukemia virus type-I (HTLV-I) the prognosis of which still remains very poor. A possible role of As(2) O(3) for the treatment of ATL is demonstrated from evidence that As(2) O(3) significantly inhibits the growth of HTLV-I infected T-cell lines and induces apoptosis in fresh ATL cells at clinically achievable concentration of the agent. The growth inhibition of As(2) O(3) treated HTLV-I infected T-cell lines was induced by both apoptosis and G(1) phase accumulation. Cleaved bcl-2 protein and an enhanced expression of bak protein in the cells were coincidentally observed during As(2) O(3) treatment. A broad spectrum caspase inhibitor, z-Val-Ala-DL-Asp-fluoromethylketone inhibited the apoptosis induced by As(2) O(3). Increased expression of p53, Cip1/p21 and Kip1/p27, and dephosphorylation of retinoblastoma protein (pRb) were detected in the As(2) O(3) treated cells. In conclusion, As(2) O(3) might become a new therapeutic tool in the treatment of ATL as As(2) O(3) induces apoptosis by destruction of the bcl-2 protein and enhancement of the bak protein production proceeding to activate caspases, and also induces G(1) phase accumulation by enhancement of p53, Cip1/p21, Kip1/p27 and dephosphorylation of pRb to HTLV-I infected T-cell lines.

Amino Acid Chloromethyl Ketones↗
PubMed2000

DNA polymorphism analysis of a pure non-gestational choriocarcinoma of the ovary: case report.

A 45-year-old nulligravida woman died from carcinoma peritonitis with choriocarcinoma arising in the ovary. This tumor was resistant to chemotherapy after debulking surgery. DNA polymorphism analysis was useful in proving the choriocarcinoma to be non-gestational carcinoma. In this paper, the clinical course and DNA polymorphism findings are mainly discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Capsaicin-induced muscle hyperalgesia in the exercised and non-exercised human masseter muscle.

AIMS: Strong jaw muscle exercises such as tooth grinding in sleep bruxism are frequently believed to be a predisposing factor in myogenous types of temporomandibular disorders. However, it is not known whether tooth grinding in sleep bruxism is associated with increased sensitivity to intramuscular stimuli. This study therefore compared the hyperalgesic effects of an intramuscular injection of capsaicin into the right masseter with and without a prior experimental tooth-grinding exercise. METHODS: Ten healthy men participated in 2 randomized sessions (exercise, non-exercise session) separated by 1 week. In the exercise session, 0.1 mL capsaicin (100 micrograms/mL) was injected into the right masseter immediately after 45 minutes of experimental tooth grinding. In the non-exercise session, the exact same paradigm was used, except that the experimental tooth grinding was omitted. The perceived intensity of pain evoked by intramuscular capsaicin was scored on a 100-mm visual analog scale (VAS). Pain detection thresholds (PDTs) to pressure stimuli and maximal voluntary occlusal force (MVOF) were measured before capsaicin injection; 5, 15, and 45 minutes after the injection; and once a day for the following 3 days. RESULTS: Injections of capsaicin into an exercised or non-exercised masseter did not cause significant differences in peak pain intensity on the VAS (57 +/- 6 mm in exercised masseter vs. 53 +/- 6 mm in non-exercised masseter; P = 0.464). The PDTs in the exercised masseter were significantly decreased for up to 1 day after the capsaicin injection (P < or = 0.038), whereas PDTs in the non-exercised masseter were decreased for only 5 minutes (P = 0.017). The MVOF on the right side was decreased 5 minutes after the capsaicin injection in both sessions (P < 0.010). The MVOF on the left side was significantly reduced for up to 15 minutes after the capsaicin injection in the exercise session only (P < 0.019). CONCLUSION: Increased sensitivity to percutaneous pressure stimuli probably reflects a post-exercise muscle soreness following tooth grinding, whereas intramuscular sensitivity to noxious chemical stimuli immediately following exercise seems to be unchanged.

Adult↗
PubMed1999

Factors that predict intrahepatic recurrence of hepatocellular carcinoma in 81 patients initially treated by percutaneous ethanol injection.

BACKGROUND: In Japan, where liver transplantation has not been used to treat patients with hepatocellular carcinoma (HCC), percutaneous ethanol injection (PEI) has been employed for those with small HCCs that are not amenable to surgical resection. In the current study, the authors evaluated PEI as a treatment for HCC patients by studying recurrence rates and survival after treatment. They then examined the clinicopathologic factors that predicted patterns of local and distant intrahepatic recurrence. METHODS: For 81 patients who underwent PEI as initial therapy between 1990 and 1997, the cumulative recurrence and survival rates and their correlations with 16 clinicopathologic factors were studied using the Kaplan-Meier method. RESULTS: The 3-year overall cumulative rates of intrahepatic recurrence and survival were 81% and 84%, respectively. At the end of the observation period, intrahepatic recurrence was detected in 56 patients (69%). In 21 (38%) of 56 patients, local recurrences were significantly associated with earlier stages of underlying cirrhosis, decreased indocyanine green retention at 15 minutes (ICG R15), larger tumor size, and histologically advanced tumor grade. Distant intrahepatic recurrence was also significantly associated with liver function and ICG R15. CONCLUSIONS: PEI is most effective as the initial treatment for patients with well-differentiated HCC when the tumor is less than 15 mm in greatest dimension. However, local recurrence depends predominantly on the biologic characteristics of the tumor, regardless of the efficacy of PEI. Surgical resection of HCC should be considered, especially for patients with mild liver dysfunction.

Aged↗
PubMed1999

Detection and cloning of an X-linked locus associated with a NotI site that is not methylated on mouse inactivated X chromosome by the RLGS-M method.

In looking for genes that escape X chromosome inactivation, we scanned the methylation status of genomic DNA from XX, X0, and XY mice using the method of restriction landmark genomic scanning using methylation-sensitive endonuclease. We detected and cloned a candidate locus and identified the Orf1 gene. Orf1 has sequence similarities to the B2 repetitive element and human CXORF4 (formerly called EXLM1), which escapes X inactivation. The B2 element spans the 3' terminus of the ORF and the 3' UTR of Orf1. The Orf1 gene encompasses 18.5 kb of genomic DNA including 11 exons and 10 introns. Taking advantage of genomic polymorphisms present between MSM and C3H/He, we showed that murine Orf1 is mapped to the proximal region of the X chromosome. Despite the unmethylation of the NotI site, Orf1 is subject to X inactivation.

Amino Acid Sequence↗
PubMed1999

Involvement of mutations in the DPC4 promoter in endometrial carcinoma development.

To define the target of chromosome 18q loss of heterozygosity, which is prevalent in endometrial carcinomas, we made a deletion map from 64 tumors. Loss of heterozygosity on 18q was found in 20 tumors. Among these, 14 tumors carried deletions at the 18q21.1 region, where the DPC4 gene is located. DPC4 transcription was disturbed in all six of the tumors with deletions at 18q21.1 examined, which sharply contrasted with the positive transcription in 12 tumors that retained heterozygosity at the 18q21.1 region. However, in the 14 tumors with the 18q21.1 deletions, the remaining allele had the wild-type sequence of the DPC4 coding region instead of somatic mutations in the DPC4 coding region. We found a one- and two-base substitutions in the DPC4 promoter in two of the six tumors that showed disturbed DPC4 transcription. Chloramphenicol acetyltransferase assays clearly demonstrated that the mutant promoters had the potential to suppress or silence DPC4 transcription, implicating the DPC4 gene in endometrial carcinoma.

Alleles↗