Immunohistochemically demonstrated suppressed expression of tryptophan oxygenase, a marker for liver differentiation, within putative preneoplastic rat liver lesions

The behaviour of rat liver putative preneoplastic lesions withrespect to the enzyme tryptophan oxygenase (TO), a liver-specificdifferentiation marker, and a possible growth-related marker,glucose-6-phosphate dehydrogenase (G6PD) was investigated duringand after their induction by diethylnitros-amine initiationand subsequent ‘selection pressure’. Using specificantibodies to rat liver TO and G6PD and the avidin-biotin complexmethod for immunohistochemical staining it was demonstratedthat all of the nodular lesions showing increased expressionof G6PD during the induction phase were also negative or deficientin TO enzyme protein. With the onset of ‘phenotypic instability’or loss of marker enzymes, a gradual return to normal expressionof TO activity was evident. Administration of dexamethasoneand L-tryptophan 11 weeks after cessation of carcinogen treatmentallowed differentiation between morphologically altered, apparentlypersisting lesions in which no, or little, enzyme inductionwas apparent and instable lesions showing a strong increasein levels of TO protein. Thus, persisting nodular lesions sharea common lack of response to normal homeostatic physiologicalcontrol.     

Long term results of transsphenoidal adenomectomy in patients with Cushing's disease

As part of an ongoing series, 100 patients with Cushing's disease underwent transsphenoidal operations. Pituitary adenomas were confirmed in 93 patients, and initial remission was achieved in 86 (92%) of them. Hypercortisolemia was not corrected in 7 patients, and in 4 this was due to invasive adenomas. These patients were subjected to irradiation, medical treatment, or both after operation. Only 7 of the 100 patients had no pituitary adenoma found at operation, and they obtained no clinical remission even after partial or subtotal hypophysectomy. Follow-up review, with an emphasis on endocrinological studies, was performed on these patients for a mean period of 38 months. Seventy-eight patients were in long term remission after operation and had restoration of noncorticotropic hormone secretion as well as pituitary-adrenal function. Recurrence was noted in 8 patients after 19 to 82 months in remission. In all of these patients, pituitary adenomas were verified by reoperation and no case of corticotrophic cell hyperplasia was noted. We conclude that late recurrence of Cushing's disease may occur after adenoma removal and is due to the regrowth of adenoma cells left behind in the peritumoral tissue at the first operation. In view of the overall remission rate, transsphenoidal adenomectomy is considered a highly effective treatment for Cushing's disease.     

A possible involvement of oxygen free radicals in the development of myocardial acidosis during coronary occlusion in dogs

Summary The present study was designed to examine whether free radical scavengers attenuate myocardial acidosis induced by partial occlusion of the coronary artery in dogs. The myocardial pH was determined by a micro glass pH electrode inserted in the endocardial layers of the left ventricular wall perfused by the left anterior descending coronary artery. The left anterior'descending coronary artery was occluded for 90 min incompletely so that the flow would be 1/2–1/3 the original flow. The myocardial pH before partial occlusion was 7.54–7.55. Partial occlusion decreased the flow in the left anterior descending coronary artery by 49.3–64.9% and the myocardial pH by 0.71–0.76, and increased the ST segment (surface electrocardiogram) by 6.3–9.3 mV. Saline (0.5 ml/kg), recombinant human superoxide dismutase (70,000 or 210,000 U/kg), or catalase (55,000 or 165,000 U/kg) was injected intravenously 30 min after partial occlusion. The injection of recombinant human superoxide dismutase or catalase alone did not restore the myocardial pH that had been decreased by coronary occlusion. The combined injection of recombinant human superoxide dismutase (70,000 U/kg) + catalase (55,000 U/kg), however, restored the myocardial pH without restoration of ST segment. In conclusion, recombinant human superoxide dismutase + catalase attenuated myocardial acidosis during ischaemia, suggesting a possible involvement of oxygen free radicals in the development of myocardial acidosis (especially in the endocardial layers) during ischaemia. Send offprint requests to Y. Abiko at the above adress     

A treatment of intractable sternal osteomyelitis--significant use of pedicle muscular flaps

In recent years, the greater omentum of pedicle muscular flap has been used to treat chest wall infection and Sternal Osteomyelitis following cardiac or respiratory surgery. In Japan, however, there has been an increasing number of cases in which neither the greater omentum Nor the rectus muscle can be used due to the comparatively young age of the patient. There are also many cases undergoing abdominal surgery for malignant tumor and bypass surgery of the coronary artery in which the internal thoracic artery (ITA) and gastroepiploic artery (GEA) are used. We studied three such cases; a case of coronary aortic bypass graft (CABG) where ITA from both the right and left sides were used following stomach resection; a case in which CABG and gallbladder resection were carried out simultaneously; and a case of sternal osteomyelitis is years following surgery for ventricular septal defect. All three cases had undergone reconstructive surgery using the pectoralis major muscle or a pedicle muscular flap from the latissimus dorsi muscle. It is estimated that cases of CABG using both the right and left sides of ITA and GEA, cases of the elderly as well as cases of children will continue to increase. Consequently, cases of sternal osteomyelitis in which neither the omentum nor rectus muscle can be used will also increase. Therefore, it is considered that treatment using pedicle muscular flaps from the breast or dorsal area may be very effective. Herein, we report on the choice of treatment and its results.     

Standardization of immunoassay for CRM-related proteins in Japan: from evaluating CRM 470 to setting reference intervals.

The Japan National Institute of Health (JNIH), in close collaboration with academic societies, commercial companies, and the Japan Society of Medical Technologists, has led in the attempt to standardize plasma protein assays since the mid 1980s. Under a framework of global standardization, they used WHO primary reference materials to reduce discrepancies in values reported for proteins assayed using different systems, thus laying the foundations for a protein immunoassay standardization system in Japan. With the introduction of CRM 470 in 1993, the Japanese Committee for Clinical Laboratory Standards (JCCLS) has taken the initiative in promoting the use of the new material and bringing about the re-evaluation of all systems of quality assurance in clinical laboratories. This eventually led to the establishment of reference intervals in Japanese populations of children and adults after preparation of assigned calibrators from CRM 470 for each assay system. Here we review the history of a series of projects carried out in Japan and describe several remaining problems, through which we will attempt to evaluate the potential value of protein immunoassay standardization.     

Diagnostic and epidemiological implications of regional differences in serum concentrations of proteins observed in six Asian cities.

The IFCC Committee on Plasma Proteins has been investigating regional differences for commonly assayed plasma proteins to determine whether universal reference intervals can be applied. As a part of this study, we launched an Asian project analyzing the concentrations of 13 serum proteins whose values are standardized to CRM470, and five newer analytes: retinol-binding protein (RBP), cystatin C (CysC), light-chain-kappa (L-kappa), and light-chain-lambda (L-lambda). In Tokyo, Seoul, Kuala Lumpur, Hong Kong, Taipei and Shanghai, serum samples were collected from 146 to 415 apparently healthy individuals with nearly equal gender ratios. All assays were performed in Tokyo on a Behring Nephelometer II (BN II). Seven chemical analytes (aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (gammaGT), creatinine, total cholesterol (TC), triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C)) were also measured. These results were used for excluding individuals with possible latent clinical disorders. Positive acute phase reactants were consistently lower, and negative ones were higher, in Tokyo than those in other cities. The most conspicuous difference was observed in C-reactive protein (CRP). There were no regional differences in transferrin, albumin, or CysC. Creatinine was much lower in Tokyo despite comparable CysC levels. ALT and gammaGT were higher in Shanghai, Taipei and Seoul; gammaGT and TG were higher in Shanghai; and HDL-C was higher in Tokyo. Gender-related differences in reference intervals were observed for immunoglobulin (Ig)M, haptoglobin, RBP, transferrin, alpha2-macroglobulin (A2M), transthyretin, alpha1-acid glycoprotein, CysC, and C4 in all cities. Slight age-related differences were observed, irrespective of the region, in IgA and ceruloplasmin (increase) and A2M (decrease). Environmental factors and lifestyle seem to have a great influence on many commonly measured analytes.     

Effect of ubenimex on the immune system of patients with hematological malignancies

The effect of in vivo administration of ubenimex (Bestatin) on the immune status of patients with hematological malignancies in remission was studied. Natural killer (NK) cell activities, lymphokine activated killer (LAK) cell activities, production of interferon-gamma (gamma-IFN) and surface antigens of peripheral lymphocytes were examined before and after administration of ubenimex. Analysis of the T, B and NK cell compartment ax conducted by assessing expression of the following antigens: CD3+CD19- (T), CD3-CD19+ (B), CD8+CD11b- (Tc), CD8+CD11b+ (Ts), CD4+Leu8-(Th), CD4+Leu8+(Ti), CD16CD57 (NK) using a 2-color flow cytometric analysis. NK and LAK activity was significantly lower in patients with hematological malignancies as compared to normal subjects. The absolute numbers of lymphocytes and NK cells were also lower than those in healthy controls. The reduced NK and LAK activity, however, was elevated after ubenimex administration. The absolute numbers of helper T cells, cytotoxic T cells and NK cells were also increased after administration of the drug. These findings were not observed in patients treated without ubenimex. Serum levels of IFN-gamma were not markedly changed after ubenimex administration. But peripheral blood mononuclear cells cultured with rIL2 showed appreciable levels of IFN-gamma production, and production increased after ubenimex administration. These results shows that ubenimex is a powerful immunomodulator that augments or restores some immune functions in patients with hematological malignancies.     

Evidence-based laboratory interpretation system built on a large collection of case records with well-defined diagnoses.

A computer-based system for laboratory diagnosis was created to promote evidence-based practice of laboratory medicine. It runs on a database consisting of 1992 well-defined untreated cases from 38 common diagnostic categories. Clinical symptoms, signs, and severity were recorded together with laboratory test results both general and specific to the clinical diagnosis. The system has two modes in which to view the database: either single or multiple diagnostic categories at a time. In the single mode, it allows flexible filtering and quick subgrouping of cases within the diagnostic category by specifying parameters of interest. It is also capable of computing a similarity index of a case at hand to those in the database. The index is defined as a weighted sum of log-likelihood calculated dynamically from parameters chosen for the query. In the multi-mode, only the parameters commonly recorded in selected categories are retrieved from the database. The system offers a between-category comparison view of any parameter. The similarity indices can be also computed among categories to see how well a set of parameters differentiates a reference category from the others.     

Evidence for nonclonal hematopoietic progenitor cell populations in bone marrow of patients with myelodysplastic syndromes

Clonality of marrow hematopoietic progenitor cells in myelodysplastic syndromes (MDS) was analyzed by X-chromosome inactivation pattern using polymerase chain reaction (PCR). Five female patients were included in this study; two with refractory anemia (RA) and three with RA with excess blasts (RAEB). They were heterozygous for BstXI restriction fragment length polymorphisms (RFLP) of the X-chromosome-linked phosphoglycerate kinase (PGK) gene. In each patient, erythroid and nonerythroid colonies, grown in the presence of erythropoietin and granulocyte-macrophage colony-stimulating factor (GM-CSF), exhibited no remarkable difference in clonal constitution. Two patients showed only one methylation pattern, suggesting the monoclonal origin of hematopoietic progenitor cells. Colonies of two other patients exhibited predominant and minor methylation patterns in PGK gene, indicating that nonclonal progenitor cells remain a minor population. The bone marrow of one patient appeared to contain a greater proportion of nonclonal progenitors. Stem cell factor (SCF), a potent colony- stimulating factor, enhanced both erythroid and nonerythroid colony formation. However, it did not notably alter the clonal constitutions. We conclude that nonclonal hematopoietic progenitor cells can persist in a substantial number of MDS patients.