Comparison of image reconstruction algorithms in myocardial perfusion scintigraphy

The purpose of this study was to compare the clinical utility of two image reconstruction algorithms in myocardial perfusion SPECT (single-photon emission computed tomography): filtered back-projection (FBP) and ordered subset expectation maximization (OSEM). A rest/stress one-day protocol with 99mTc-MIBI or tetrofosmin was performed on 102 consecutive patients who underwent coronary angiography. After SPECT data acquisition, images were reconstructed with FBP and OSEM algorithms. We assessed diagnostic performance (sensitivity, specificity and accuracy) in detecting coronary artery stenosis and evaluated regional tracer uptake with a 4-point scoring system. Although there were no significant differences in diagnostic performance between FBP and OSEM reconstruction, the OSEM method yielded higher uptake in the RCA area than the FBP method by reducing the count-loss artifact due to hepatic uptake of the tracers. In addition, regional uptake in the LCX area was significantly lower in the OSEM image than in the FBP image; this phenomenon was observed mainly in patients with coronary stenosis and/or infarction in the LCX territory. In conclusion, OSEM and FBP offered comparable diagnostic performance in stress myocardial perfusion SPECT. The OSEM method contributed to reduction of the count-loss artifact in inferior and posterior walls and to easy recognition of hypoperfusion in the LCX area.     

A case of mosaic Klinefelter syndrome associated with isodicentric Yp

We describe a case of mosaic Klinefelter syndrome demonstrating an isodicentric Y chromosome. A 70-year-old man visited our outpatient clinic complaining of dysuria resulting from atrophy of the penis. His height was 170 cm and his weight was 60 kg. A serum hormonal analysis revealed hypergonadotropic hypogonadism. A chromosomal analysis with fluorescence in situ hybridization revealed four cell lines in which the karyotypes were 47,XXY, 46,XY, 46,XX and 47,XX,idic(Y) (q11.2). To the best of our knowledge this is the first case of mosaic Klinefelter syndrome bearing an isodicentric Y chromosome. The origin of the isodicentric Y is discussed.     

Fluid and electrolyte balance in extremely preterm infants <24 weeks of gestation in the first week of life

Background: Extremely preterm infants, especially those <24 weeks of gestation, displayed extremes in changes of fluid/electrolyte balance. The purpose of the present study was to retrospectively investigate abnormalities in fluid/electrolyte balance during the first postnatal week.
Methods: Of 32 subjects admitted during 20 years, 17 infants with no severe complications were examined, and 72 appropriate-for-dates infants at 24–28 weeks of gestation were taken as controls. The subjects were managed in closed incubators in a highly humidified environment and fluid/electrolyte balances were monitored in retrospect.
Results: The subjects had higher urine contents, while the insensible water loss was higher than in controls. As for weight loss, no remarkable changes were noted between the two groups. On day 4 and thereafter, serum Na⁺ levels were high, indicating a high complication rate of hypernatremia without differences in hyperkalemia. The decrease in blood base excess was rapid, requiring supplementation of sodium bicarbonate up to postnatal day 5 in all preterm infants.
Conclusion: Due to the relatively higher urine output and insensible water loss in extremely preterm infants during postnatal week 1, higher water intake was required. As such, metabolic acidosis was bound to have occurred.     

The Induction of Cytotoxic T Lymphocytes against HLA-A Locus-matched Lung Adenocarcinoma in Patients with Non-small Cell Lung Cancer

To induce cytotoxic T lymphocytes (CTL) against non-small cell lung cancer (NSCLC) efficiently, the induction of CTL was attempted using HLA-A locus-shared allogeneic NSCLC cells. T cells derived from either tumor tissue specimens or the regional lymph nodes of patients with NSCLC were stimulated twice or three times with an HLA-A2/A24-positive NSCLC cell line (PC-9), and thereafter the cytotoxic activity was examined by ⁵¹Cr-release assay. In patients with HLA-A24/ adenocarcinoma, anti-PC-9 cytotoxicity was induced in all 6 patients tested. Anti-PC-9 cytotoxicity was induced in 2 out of 5 patients with HLA-A2 (A24⁻)/adenocarcinoma, in 2 out of 4 patients with HLA-A24/squamous cell carcinoma, and 1 of 2 patients with HLA-A2/squamous cell carcinoma. The cytotoxic activity was observed to kill PC-9 selectively, not other NSCLC lines, and the activity was substantially blocked by anti-MHC class I antibody, but not by anti-MHC class II antibody. The PC-9-specific CTL produced γ-interferon in response to autologous tumor cells. These results indicated that the anti-PC-9 cytotoxicity was mediated by cytotoxic T lymphocytes that may recognize the T cell epitope(s) shared and presented by HLA-A2 and/or HLA-A24-positive NSCLC.     

Restriction of T cell receptor variable region in lymph nodes of adult T cell leukemia/lymphoma

Adult T cell leukemia/lymphoma (ATLL) is a mature T cell malignancy, especially derived from the CD4 positive T cell. To characterize the T cell, we examined the representation of T cell antigen receptor variable region, using the monoclonal antibodies [β V 5 (a), β V 5 (b), β V 6 (a), β V 8 (a), β V 12 (a), α V 2 (a), α-β V (a)]. Clinicopathologically we classified the lymph nodes of patients with ATLL into three states (1) human T cell leukemia virus type I (HTLV-I) associated lymphadenitis, reactive state; (2) incipient ATLL, early or pre-neoplastic state; and (3) ATLL, neoplastic state. The lymph nodes of all three states were composed of unvarying CD4 positive T cells. Most of the lymph nodes with ATLL consistently presented α V 2 antigen, but no others. In HTLV-I associated lymphadenitis, only a few cells reacted for α V 2, as in non-specific lymphadenitis without ATLL features. One of three cases with incipient ATLL presented α V 2. The selective expression of T cell antigen receptor V region might be associated with the presence of HTLV-I encoded superantigen, similar to human immunodeficiency virus (HIV).     

Bone Marrow Transplantation for Hematologicai Diseases in Hokkaido--June 1985 to December 1991

Bone marrow transplantation (BMT) was started in Hokkaido in1985. In the present report we have reviewed the clinical outcomeof patients treated with BMT for hematologicai diseases in Hokkaido.Fifty-eight allogeneic and 19 autologous transplants were registeredby December 1991. The underlying diseases consisted of 47 leukemias,14 lymphomas, 10 aplastic anemias and six myelodysplastic syndromes.Among the allogeneic BMT cases, 55 were human leuhocyte antigen(HLA) identical and three were mismatched. Among the autologousBMT patiets, two recieved their marrow purged with 4-hydroperoxycyclophosphamideand five, with monoclonal antibodies and complements. The conditioningregimens used for malignancies were chiefly cyclophosphamide(CY) plus total body irradiation, or busulfan plus CY. In manycases, cytokines were used for rapid recovery of decreased leukocytes.Engraftment was observed in 50 out of 52 evaluated allogeneicand 18 out of 19 autologous transplants. Ten allogeneic patientssuffered from severe acute graft-versus-host diseases (GVHD),and extensive chronic GVHD appeared in 16 patients. Relapseswere observed in four cases of allogeneic BMT and six of autologous.BMT. The major complications were interstitial pneumonitis (IP)and severe infections. Long-term, survival rates were almost60% in both allogeneic and autologous transplants. Mild acuteGVHD and limited chronic GVHD increased the survival rates.The results indicated that substantial problems such as GVHD,IP and relapses must be controlled in the near future for animproved outcome to be made possible.     

Clinical Application of Serum Pepsinogen I and II Levels for Mass Screening to Detect Gastric Cancer

A considerable number of gastric cancers derive from stomach mucosa where chronic atrophic gastritis is severe and extensive. Based on the fact that the serum pepsinogen levels provide a precise measure of the extent of chronic atrophic gastritis, we have devised a mass screening method involving serum pepsinogen measurement to identify subjects at high risk of gastric cancer. In 1991, we screened 4,647 workers (male: 4,113, female: 534, mean age: 49.0 years) at a Japanese company using this method. Out of 875 subjects (18.8%) with a serum pepsinogen I level of less than 50 μg/liter and a pepsinogen I/II ratio of less than 3.0, 676 subjects (14.5%) were selected for further investigation by endoscopy. This led to the detection of four subjects (0.086%) with gastric cancer (three in an early stage) and four subjects with adenoma. The cancer detection rate of this new screening method was comparable, and in some respects superior, to that of the traditional barium X-ray screening. Since the incidence of test-positive subjects was as low as 10% amongst subjects aged less than 40, this screening method appears to be especially useful for screening of younger generations. The new method is less expensive than the traditional barium X-ray and subjects experience little discomfort. Further, many serum samples can be quickly measured simultaneously. The results of this study have indicated that serum pepsinogen screening provides a valuable method for detecting gastric cancers.     

Anti-tumor-promoting action of FK506, a potent immunosuppressive agent

The effect of FK506, a potent immunosuppressive agent, on 7,12-dimethylbenz[a]anthracene-initiatedand 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted skinpapilloma formation was examined in CD-1 mice. A topical applicationof FK506 to mouse skin 15 min before each TPA treatment resultedin a dose-related inhibition of tumor formation. FK506 (1 µmol)almost completely inhibited tumor formation. This inhibitoryeffect of FK506 was not due to any damage inflicted on the initiatedcells but due to its antitumor-promoting action. A topical applicationof FK506 also inhibited epidermal ornithine decarboxylase inductionand skin inflammation caused by TPA in a dose-related manner.Significant inhibition by FK506 of TPA-induced endogenous proteinphosphorylation in intact epidermal cells was not detected.These results indicate that FK506 inhibits TPA-induced tumorpromotion at a step distal to the endogenous protein phosphorylationby TPA.     

Interaction of Aluminum with PHFτ in Alzheimer’s Disease Neurofibrillary Degeneration Evidenced by Desferrioxamine-Assisted Chelating Autoclave Method

To demonstrate that aluminum III (Al) interacts with PHFtau in neurofibrillary degeneration (NFD) of Alzheimer's disease (AD) brain, we developed a "chelating autoclave method" that allows Al chelation by using trivalent-cationic chelator desferrioxamine. Its application to AD brain sections before Morin histochemistry for Al attenuated the positive fluorescence of neurofibrillary tangles, indicating Al removal from them. This method, applied for immunostaining with phosphorylation-dependent anti-tau antibodies, significantly enhanced the PHFtau immunoreactivity of the NFD. These results suggest that each of the phosphorylated epitopes in PHFtau are partially masked by Al binding. Incubation of AD sections with AlCl(3) before Morin staining revealed Al accumulation with association to neurofibrillary tangles. Such incubation before immunostaining with the phosphorylation-dependent anti-tau antibodies abolished the immunolabeling of the NFD and this abolition was reversed by the Al chelation. These findings indicate cumulative Al binding to and thereby antigenic masking of the phosphorylated epitopes of PHFtau. Al binding was further documented for electrophoretically-resolved PHFtau on immunoblots, indicating direct Al binding to PHFtau. In vitro aggregation by AlCl(3) was observed for PHFtau but was lost on dephosphorylation of PHFtau. Taken together, phosphorylation-dependent and direct PHFtau-Al interaction occurs in the NFD of the AD brain.