[Nocardiasis. Apropos of a case report. Literature review]. We report the observation of a cutaneous, pulmonary and osseous nocardiosis in a 45-year-old man. He was iatrogenously immunocompromised because of a "self-medication" with 32 mg per day of methylprednisolone during 30 months for gouty arthropathies. Under treatment with several antibiotics, a favourable evolution was obtained.


Detection of human papillomavirus DNA in invasive cervical cancers by the polymerase chain reaction and its clinical significance. In order to detect human papillomavirus (HPV) DNA in invasive cervical cancers, three different polymerase chain reactions to amplify different subgenomic fragments of HPV DNA were carried out on DNA extracted from 93 formalin-fixed and paraffin-embedded tumor tissues. This study detected HPV DNA in 54 cases (58.1%), which broke down to HPV 16 in 39 (41.9%) cases, HPV 18 in six (6.4%), HPV 52 in three, HPV 33 in one and unclassified HPV type in the remainder. Histopathologically, squamous cell carcinomas frequently contained HPV 16, whereas, HPV 18 was present in adenocarcinoma, adenosquamous cell carcinoma and small cell carcinoma of the cervix. Clinicopathological study revealed that HPV 16 and 18 DNA found were more frequently than other HPV subtypes in premenopausal patients. Moreover, HPV 18 DNA-positive cancers had a relatively high recurrence rate. These results indicate that cervical cancers might be clinically influenced by the difference in subtypes of the infecting HPV.


Clear cell hepatocellular carcinoma with abundant myxoid stroma. A case of the clear cell variant of hepatocellular carcinoma with an abundant myxoid stroma is presented. The tumor occurred in a 55-year-old Japanese man, and swelling of the scrotum was the initial symptom. The patient underwent high-level orchiectomy, and the pathologic diagnosis was a metastatic tumor on the surface of the processus vaginalis and intact testis. Extensive examination failed to show a primary site. Subsequent autopsy revealed a large hepatic tumor and metastatic nodules with a prominent myxoid appearance in multiple organs. Histologically, each tumor consisted of uniform small tumor cells with clear cytoplasm attributed to abundant accumulation of glycogen particles, and an abundant myxoid stroma was also present. The tumor cells were positive for keratin, alpha 1-antitrypsin, alpha 1-antichymotrypsin, liver ferritin, prealbumin, and fibrinogen, but lacked alpha-fetoprotein. These findings indicated that this case was hepatocellular carcinoma of the clear cell type with a prominent myxoid stroma.


Hepatocellular carcinoma containing endocrine cells. An autopsy report of triplecancer involving the liver, kidney and thyroid. An autopsy case of triplecancer (hepatocellular carcinoma of the liver, renal cell carcinoma of the kidney, and papillary carcinoma of the thyroid) was reported. Histological features of primary hepatic tumor suggested undifferentiated hepatocellular carcinoma (Edmondson-Steiner's Grade IV). However, certain tumor cells showed distinctive argyrophilic reactions and electron microscopy revealed small round granules resembling electron dense endocrine secretory granules in their cytoplasm. Immunohistochemistry demonstrated that tumor cells showed a positive reaction for AFP while some others were positive for chromogranin-A. Immunohistochemical demonstration of AFP production by tumor cells indicated their hepatocyte origin. No endocrine syndrome had been present and no alternative primary source of the endocrine tumor was detected. Tumors of the kidney and thyroid were considered to be incidentally combined.


Effect of six virustatic nucleoside analogues on the development of fetal rat thymus in organ culture. The effects of the virustatic agents zidovudine (azidothymidine, AZT) 2'3'-dideoxycytidine (ddC), 2'3'-dideoxyinosine (ddI), acyclovir (ACV), ganciclovir (GCV), and vidarabine phosphate (VP) on the in vitro development of thymic lobes of 17-day-old rat fetuses were tested in an organ culture system. The virustatics were added to the medium for a culture period of 7 days. All nucleoside analogues inhibited the proliferation and differentiation of lymphatic cells. However, differences were observable with respect to the potency of the six drugs to interfere with thymic development. Compared to untreated controls, reduction in the number of thymocytes was significant at concentrations of 30 microM AZT and ddI. In the case of ACV, GCV, VP, and ddC concentrations as low as 10 microM were sufficient to cause a significant reduction, ddC being the most potent derivate. Increasing concentrations of the nucleoside analogues led to a dose-dependent further inhibition of cell proliferation. At a concentration of 30 microM flow cytometry revealed a decrease in the relative number of double positive CD4+ CD8+ and single positive CD4+ CD8- cells but an increase in the relative number of CD4-CD8+ cells. At the same concentration the expression of the CD5 antigen was reduced by the antimetabolites, indicating that maturation of the thymocytes was inhibited. Distribution of the forward light scatter, a cell size-related parameter, showed that the formation of small thymocytes was reduced by the nucleoside analogues. Light and electron microscopic investigations indicated cytotoxic effects of the drugs on the thymocytes, whereas the epithelium was only slightly affected.


Effect of lithium on rat embryos in culture: growth, development, compartmental distribution and lack of a protective effect of inositol. Lithium chloride (LiCl) was tested at various concentrations (50, 100, 150 and 200 micrograms/ml) using a rat whole-embryo culture system beginning on gestation day 9.5 (headfold stage) in order to establish a concentration-response relationship. Open neural tubes--as described in former publications (Tesh 1988)--were not induced by lithium. A significant reduction of embryonic growth and development occurred at the lowest concentration tested (50 micrograms/ml). Clear-cut dysmorphogenetic effects (absence of the eye cup, kink in the spinal anlage, "bleb" at the rostral head region) occurred at a concentration of 150 micrograms/ml LiCl. LiCl concentrations in the embryo, visceral yolk sac, exocoelomic fluid and medium were determined after the embryos had been cultured for 48 h in the presence of a moderately embryotoxic dose of LiCl (3.5 mEq/l or 150 micrograms/ml). Medium supplementation with myo-inositol in different concentrations was ineffective in antagonizing the embryotoxicity induced by LiCl.


Postmenopausal endometrioma and hormonal replacement therapy. This case of postmenopausal endometrioma following hormonal replacement therapy (HRT) demonstrates the often forgotten possibility of reactivation of endometriosis with HRT. The diagnosis of endometriosis should be considered in a postmenopausal woman who presents with pelvic pain and mass whilst on HRT.


Implication of acid cholesteryl ester hydrolase in the regulation of steroid biosynthesis in rat Leydig cells. Cholesteryl ester hydrolase (CEH) activities with different pH optima, i.e. at about pH 4.0 and pH 7.0, were found in Leydig cells isolated from rat testis. Highly purified intact Leydig cells responded to human chorionic gonadotropin treatment with increased intracellular cAMP levels, increased testosterone release, and a 1.5-fold stimulation of the acid CEH activity. Treatment of non-stimulated homogenised cells with cAMP-dependent proteinkinase, cAMP and ATP lead to a 3.0-fold stimulation of the acid CEH activity. These findings suggest that interconvertible CEH with an acidic pH optimum--presumably of lysosomal location--contributes to the regulation of steroidogenesis in Leydig cells.


Bull seminal plasma phosphodiesterase. Purification and general properties. A phosphodiesterase from bull seminal plasma was purified to homogeneity. The purification procedure involved sequential column chromatographies on DEAE-Sephadex A-50, ConA-Agarose, chromatofocusing and AMP-Agarose. The final yield was about 20% with a 3000-fold purification. As indicated by chromatofocusing, the enzyme is an acidic protein (pI approximately 4.6) and owing to its interaction with Concanavalin A it is also a glycoprotein. The SDS-PAGE showed that the purified phosphodiesterase seemed to be constituted of a single polypeptide chain of about 125 kDa. The enzyme did not show an absolute substrate specificity. Thus, it was able to hydrolyze 4-nitrophenyl ester of 5'-TMP (but not of 3'-TMP), cAMP, nucleic acids as well as NAD+, ADP and ATP. According to its enzymatic properties, bull seminal plasma phosphodiesterase is to be considered an oligonucleate 5'-nucleotidohydrolase. In addition the seminal plasma phosphodiesterase also showed phosphonate esterase activity.


Patterns of alpha-1-adrenergic receptor expression in regenerating and neoplastic hepatic tissue. As norepinephrine is a potent hepatocyte comitogen through binding to the alpha 1-adrenergic receptor, we have examined mRNA levels of the alpha 1a- and alpha 1b-adrenergic receptor subtypes in normal and regenerating rat hepatocytes as well as in several different rat hepatoma cell lines. All rat hepatomas examined lacked both alpha 1a- and alpha 1b-receptor message and receptor binding in radioligand binding experiments, suggesting that the growth of dedifferentiated neoplastic rat hepatocytes is not regulated by the alpha 1-adrenergic receptor. Interestingly, unlike the rat hepatomas analyzed, the human hepatocellular carcinoma cell line, HepG2, was positive for both alpha 1a and alpha 1b message at 4.5 kb, yet this cell line lacked receptor binding in radioligand binding assays. While normal and regenerating liver is negative for alpha 1a-receptor expression, it is positive for alpha 1b expression and is characterized by the presence of two bands at approximately 4.0 and 3.2 kb which peaked between 20 and 48 h after partial hepatectomy. A dramatic decrease in message level of the lower band and the continued presence of the upper band between 6 and 12 h after partial hepatectomy, and before the peak in DNA synthesis in regenerating rat liver, may correspond with observed differences in alpha 1-receptor function during liver regeneration.


Coexistence of a malignant fibrous histiocytoma and asbestos exposure. Brief report. A 59-year-old male died of malignant fibrous histiocytoma. He had a history of asbestos exposure as a shipfitter in the Japanese Naval Shipyard and other shipyards for 45 years. Numerous asbestos bodies were detected in the autopsied lung and within the lesion. X-ray analysis of the asbestos fibers showed them to be crocidolite, a type of asbestos fiber commonly seen in association with mesothelioma and other types of cancer. This case adds malignant fibrous histiocytoma to the growing number of tumors that can be attributed etiologically to asbestos exposure.


Improved care of patients with small cell lung cancer. Nutritional and quality of life aspects. A comprehensive cancer care project was carried out in Uppsala with the aim of improving the overall situation for patients treated with intensive chemotherapy with curative intent. This report gives the results in 58 patients with small cell lung cancer (SCLC), focusing on the nutritional aspects of the care and chemotherapy-related adverse effects. Responses, survival and simple nutritional parameters were compared with a historical control group (n = 81), and quality-of-life parameters with a pre-project group (n = 22). Groups were comparable with respect to pre-treatment characteristics. In contrast to the historical control group, weight, body mass index and S-albumin did not decrease during treatment in patients diagnosed during the project period. Yet, food intake in the study group was low, and for most patients below what is recommended. Survival, proportion of responses and response duration did not differ from those of the control group. Compared with the pre-project quality-of-life controls, a number of scores were more favourable for study patients (n = 36) interviewed in association with the 8th treatment course by a Swedish version of the Cancer Inventory of Problem Situations (CIPS). The global score was lower in the study group than in the pre-project group (0.80 vs 1.20, p < 0.001). Significant differences in a favourable direction were also seen in several higher order factors and miscellaneous subscales constituting the CIPS. On individual items, the study group expressed less problems with appetite/food taste in hospital, nervousness before chemotherapy and worry about adverse effects. The greatest differences in positive direction for the study group were seen within areas where the project focused on caring activities. We therefore conclude that a cancer care project with the present goals and means of intervention can improve the quality of life in patients with SCLC treated with intensive chemotherapy.


Contrast-enhanced magnetic resonance imaging of the breast. Contrast-enhanced magnetic resonance imaging (MRI) of 28 patients with known breast tumors was compared with clinical findings and histopathology, and for 12 of the patients also with mammography. The dynamic measurements performed in 18 patients showed that signal intensity in gradient echo (FFE) images increased rapidly in malignant tumors after contrast injection and reached a plateau level at 1-3 min postcontrast. Fibroadenomas showed slower contrast enhancement continuing throughout the whole examination period of 10 min. The most enhancing parts of the tumors were selected for intensity measurements. The differentiation between malignant and benign tumors in dynamic contrast-enhanced MRI was in accordance with the histopathological findings in all cases. The tumor diameter as measured by MRI showed very good agreement with the size of the tumor specimens. Comparison of tumor size measurements in mammography and MRI showed that MRI had the most accurate correlation to the measured size of the tumor specimens.


Etoposide versus methotrexate in small cell bronchial carcinoma. A randomized study of two types of four-drug chemotherapy regimens. Seventy-nine patients with small bronchial carcinoma randomly received cyclophosphamide, doxorubicin, vincristine, and methotrexate, alternating after four cycles with cyclophosphamide, lomustine, vincristine and methotrexate or the same with replacement of methotrexate by etoposide in lomustine cycles. Patients with limited disease received radiotherapy with 40 Gy. In 34 patients with extensive disease the total response in the groups with and without etoposide was 89% and 69% and the median survival 10.9 and 8.2 months respectively. In 45 patients with limited disease, the complete remission rates in the groups with and without etoposide were 57% and 67%, partial remission rates 38% and 25%, and the median survival times 12.3 and 17.8 months respectively. The disease-free survival exceeding 5 years in the respective groups was 4.2% and 14.3%. A slightly better response in extensive disease and a tendency to better long-term survival in limited disease was noted but the price was increased toxicity in the latter group.


[The beta-adrenergic receptor].

[The beta-adrenergic receptor]. The Authors review the constitution and mechanism of action of the beta adrenergic receptor. It is part of a large family which includes visual pigments, muscarinic, serotonergic, olfactive and substance K receptors. Catecholamines given an electron to the receptor. It goes then successively to the alpha submit of Gs protein ant to adenylyl cyclase. The process of activation consists in a successive transfer of one electron.


Ultrahigh-resolution scanning electron microscopy of biological materials. The age of ultrahigh-resolution scanning electron microscopy (SEM) began in 1985, when the UHS-T1, with a resolution of 0.5 nm, was developed. Commercial instruments of the same or similar types followed rapidly. As instrumental resolution progressed, conventional specimen preparation methods became inadequate, and a number of new techniques were devised. In this paper, detailed procedures for these preparation methods such as the CC plate method and heavy metal impregnation are described, together with precautions recommended for achieving ultrahigh-resolution. Some applications of the method to biological specimens are also reported. Morphological identification of immunoglobulins prepared from human blood was attempted, and although the identification was not completely successful this technique may yet come to be of use in the clinical examination of allergic or infectious diseases. SEM images of complement, Clq, proteoglycan and the helical structure of double stranded DNA are shown, as also is the visualization of immunolabelled cell-surface receptors.


Abnormal cervical cytology in adolescents: a literature review. This article reviews the literature on the subject of cervical cytological abnormalities in teenagers, defined as a Papanicolaou (Pap) smear result more severe than inflammation. There is discussion of the increasing prevalence of this problem in adolescents. Behavioral and biologic risk factors are examined. The role of the human papillomavirus, widely believed to be the etiologic agent, is addressed. Atypia, its relationship to cervical malignancies, and its management are reviewed. The possible role of the human immunodeficiency virus in the increasing prevalence of cytological abnormalities in teens is considered.


[The interaction of taurine and beta-alanyl-L-histidine (carnosine) with hypochlorite anion (ClO-)]. Dipeptide carnosine and amino acid taurine have been found to actively interact with hypochlorite anion. Chloramine complexes obtained during this reaction were more stable in case of taurine. It is suggested that therapeutic effect of new Russian eye drops taufon and sevitin is due to neutralization of the reaction product hypochlorite anion catalyzed by myeloperoxidase.


[The significance of the mu- and delta-opiate receptors in realizing enkephalin action on the course of hypoxic hypoxia]. New enkephalins analogues have been synthesized. They are characterized by linear, cyclic and branched peptide chain. A relationship has been established between antihypoxic activity of opioid peptides an their interaction with opiate receptors. Compounds efficiently interacting with mu-receptors irrespective of delta-receptors affinity, promote longer survival of mice in hypoxia. The antihypoxic effect of opioids is proportional to their specificity to mu-receptors.


[The subpopulation structure of human T-lymphocytes studied by using a monoclonal antibody (MCA) to CD27]. The obtained murine mAb LT27 (IgG2a) assigned to the cluster of differentiation CD27 was used to study the distribution of antigen CD27 among human lymphocytes scbpopulations in normal state and immunopathology. In normal donors the antigen CD27 was found to be expressed most frequently on CD4+ cells (90 +/- 8% of which coexpressed antigen CD27) and to the lesser extent on- CD8+ cells (only 77 +/- 28% of CD8+ cells carried antigen CD27). 79 +/- 12% of double negative lymphocytes (CD3+CD4-CD8-) expressed antigen CD27. In patients with hypogammaglobulinemia the proportion of CD4+CD27+/CD4+ and CD8+CD27+/CD8+ was significantly reduced to 80 +/- 11% (p < 0.01) and 45 +/- 19% (p < 0.001), respectively. The ratio CD4+CD27+/CD4+ varied insignificantly with the increase of CD4+ population, but the increase of the CD8+ population was accompanied by the definite tendency to a decrease of the ratio CD8+CD27+/CD8+. The distribution of CD27 antigen inside CD4+ and CD8+ subpopulations was found to be different from the distribution of CD29 and CD45RA antigens.


[The vitamin D endocrine system and bone tissue mineral metabolism in rats with adjuvant arthritis: the effect of 1,25-dihydroxyvitamin D3]. Adjuvant arthritis was induced in male rats by injecting bacillus Calmette-Guèrin in mineral oil in a hindpaw. A decrease in bone density, calcium and phosphorus content due to polyarthritis was found in the tibia of the noninjected hind leg. Arthritic rats demonstrated serum 1,25-dihydroxyvitamin D deficiency along with constant level of 25-hydroxyvitamin D. The disease caused a significant expression of 1,25-dihydroxyvitamin D3 receptors in lymphocytes. Arthritic rats were treated with 1,25-dihydroxyvitamin D3 (0.15 mg/kg/day orally) for 35 days. The treatment prevented the development of osteoporosis and a decrease of 1,25-dihydroxyvitamin D levels as well as reduced the expression of 1,25-dihydroxyvitamin D receptors in lymphocytes.


Plasma levels of catecholamines and corticotrophin during acute glucopenia induced by 2-deoxy-D-glucose in normal man. Acute cellular glucopenia after 2-deoxy-D-glucose administration profoundly stimulates hypothalamic-pituitary-adrenocortical and adrenomedullary activity. Whether glucopenia stimulates sympathoneural release of noradrenaline is unclear. We studied 20 healthy subjects who received 2-deoxy-D-glucose (50 mg/kg in 100 ml isotonic saline) or isotonic saline (100 ml) i.v. for 30 min on each of 2 test days. Heart rate and blood pressure were measured with antecubital venous blood obtained via an indwelling catheter for assays of plasma catecholamines (noradrenaline; adrenaline; dihydroxyphenylalanine; dihydroxyphenylglycol; and dihydroxyphenylacetic acid), corticotrophin, cortisol, and glucose. 2-deoxy-D-glucose decreased diastolic blood pressure by 20% (from 69 +/- 2 to 55 +/- 2 mmHg) and increased adrenaline levels by 30-fold [21 +/- 6 (SEM) to 634 +/- 73 pg/ml], corticotrophin by sevenfold (5.1 +/- 1.2 to 35.8 +/- 4.9 pg/ml), glucose and cortisol by two-fold (82 +/- 5 to 163 +/- 9 mg/dl and 15 +/- 2 to 31 +/- 2 micrograms/dl), and noradrenaline by about 30% (224 +/- 15 to 295 +/- 24 pg/ml, p < 0.05), whereas plasma dihydroxyphenylglycol levels decreased (765 +/- 56 to 628 +/- 42 pg/ml). Small decreases in dihydroxyphenylalanine and dihydroxyphenylacetic acid levels after 2-deoxy-D-glucose did not differ from those after saline. Responses of adrenaline levels were positively correlated with those of noradrenaline (r = 0.47, p < 0.05) and glucose (r = 0.45, p = 0.06), but not of corticotrophin.(ABSTRACT TRUNCATED AT 250 WORDS)


Computer simulations of enzymatic reactions: examination of linear free-energy relationships and quantum-mechanical corrections in the initial proton-transfer step of carbonic anhydrase. Computer simulation approaches can provide a powerful tool for correlating the structure of enzymes with their catalytic activity. One of the most effective ways of simulating enzymatic reactions is provided by the empirical valence bond method. The general applicability of this method has been demonstrated in several enzymatic reactions and it is reexamined here in a study of the initial proton-transfer step in the catalytic reaction of carbonic anhydrase. The simulations produce a rate constant which is in agreement with the observed kinetic data and emphasizes the importance of the electrostatic effect associated with the catalytic zinc ion. The calculations are also used to examine the validity of linear free-energy relationships (LFERs) in enzyme catalysis and to evaluate quantum-mechanical corrections of the calculated rate constant. It is found that LFERs are valid in the present case and it is argued that this reflects the fact that the protein responds linearly to the development of electrostatic forces during the reaction. It is concluded that the present approach can be used to augment experimental studies in establishing the general validity of LFERs. It is noted, however, that such relationships are much more valid for transitions between different resonance structures than for transitions between reactants and product states.


RARA and PML genes in acute promyelocytic leukemia. Acute promyelocytic leukemia (APL) is characterized by a specific chromosome translocation t(15;17). Recently, using molecular biology techniques, a number of laboratories have demonstrated that the gene coding for the retinoic acid receptor alpha (RARA), normally located on chromosome 17, is disrupted by the t(15;17) and fused with the PML gene on chromosome 15. The chromosome 17 breaks were mapped consistently within the second intron of the RARA gene while the chromosome 15 breaks were clustered in two limited regions within the PML gene. Molecular cloning and sequence analysis of the PML gene demonstrated a complex splicing pattern and this gene may encode a transcription factor. Different isoforms of the PML-RARA fusion transcripts were discovered which are produced as a result of distinct PML gene rearrangements. Sequence analysis of the reciprocal products of the translocation t(15;17) in some APL cases suggested the implication of topoisomerase II in mediating the DNA recombination. The RT/PCR procedure has been established to characterize the expression patterns of the PML-RARA fusion gene and to detect minimal residual disease (MRD). The biological activity of the PML-RARA fusion gene and its isoforms should be further explored.


Recent results on the biology of Hodgkin and Reed-Sternberg cells. I. Biopsy material. The most recent sophisticated investigations have provided new and revealing, but also contradictory and controversial information on the biological nature and the cellular origin of Hodgkin and Reed-Sternberg cells (H-RS). Immunophenotypic analyses have shown variable phenotypic antigen expression; but, on balance the data suggest a lymphoid cell expressing T- and/or B-cell-associated markers and certain activation antigens while lacking immunological features of monocytes-macrophages or other lineages. Molecular genetic studies have demonstrated heterogenous findings with respect to rearrangements of T-cell receptor and immunoglobulin genes. Only a small percentage of the cases has rearrangements; this might be due to the threshold of sensitivity of the method combined with the scarcity of the malignant cells. Epstein-Barr virus (EBV) genomes are clonally integrated in the H-RS cells of about half the cases. The significance of these findings--whether EBV is a causative agent or an epiphenomenon--remains to be elucidated. H-RS cells express mRNA and proteins of various cytokines and cytokine receptors implying a predominant role for cytokines in the pathophysiology of HD. The mononuclear and polynuclear H-RS cells are capable of DNA synthesis and nuclear division; the lack of cellular division leads to multinuclearity through the process of endomitosis. Mutations and expression of only a limited number of oncogenes have been tested thus far. Whether the bcl-2 oncogene is involved in HD remains a matter of debate. Aneuploidy and non-random chromosomal abnormalities are the results of cytogenetic analyses of H-RS cells. However, no chromosomal marker specific for HD has yet been found. Thus, while studies of EBV involvement, growth factor production, oncogene expression and chromosomal abnormalities contributed a fair amount of new data on the nature of H-RS cells, only immunophenotyping and genotyping provided some indication of the cellular derivation: an activated lymphoid cell that possibly expresses oncogenes, that probably is infected with EBV, that most likely produces cytokines, that certainly has multiple karyotypic abnormalities.


Significance of the detection of Epstein-Barr virus DNA in lymph nodes in patients with Hodgkin's disease. Epstein-Barr virus (EBV) DNA is frequently identified in benign and malignant lymphoproliferative conditions. As shown by in situ hybridization studies viral DNA is localized within malignant cells as well as benign lymphocytes. Clonal and nonclonal EBV genomes are present in Hodgkin's disease (HD), lymphomas of the immunocompromised host and reactive lymph node hyperplasia. Lytic infection with formation of linear genomes is observed in the same conditions but appears to be infrequent in HD as shown by quantitation of mRNA coding for viral capsid antigen. Expression of the oncogene LMP (latent membrane protein) is seen in Sternberg-Reed (SR) cells and immunoblasts of AIDS-related lymphoma and infectious mononucleosis (IM). In HD, the region of the BNLF1 oncogene coding for the amino terminal and transmembrane domains (associated with oncogenic function) of LMP appears to be homogeneous whereas the region coding for the intracytoplasmic (carboxy terminal) domain of LMP is heterogeneous. Cytological similarities between SR cells and immunoblasts of IM and AIDS-related lymphomas are consistent with the hypothesis that the BNLF1 oncogene is one possible inducer of morphological features of SR cells. Whether chromosomal integration of EBV DNA is an important factor in activation of such a transforming activity remains to be elucidated. EBV DNA positive and negative HD cases with numerous SR cells lack significant mRNA expression of the two recombinase activating genes (RAG-1 and RAG-2). Therefore the SR cells appear to be derived from lymphocytes beyond the pre-B-cell or common thymocyte stage which may or may not subsequently become infected by EBV.


Megakaryocytic leukemia and platelet factor 4. The de novo megakaryocytic leukemia fulfilling the FAB criteria is still an uncommonly recognized variant of acute leukemia. Many studies have shown that the megakaryocytic leukemic events may occur at a pluripotent stem cell level and clinical observations reveal that the megakaryocytic leukemias are diverse entities. The immunophenotyping using monoclonal antibodies against platelet specific surface antigens and the ultrastructural detection of platelet peroxidase reaction do not provide sufficiently useful information to determine whether a megakaryocytic leukemia is chronic, acute, therapy-responsive or therapy-unresponsive. More sophisticated techniques are required to further characterize megakaryocytic leukemic cells. In this review, we emphasize that megakaryocytic leukemic cells can be categorized into two groups; one with the PF4 mRNA, and the other without it, and that the expression of PF4 mRNA in the blasts could be a useful marker for the identification of mature megakaryoblasts. It seems that the patients with blasts expressing PF4 mRNA will have a longer survival and a better response to chemotherapy than those without PF4. We further discuss the fact that the detection of mRNAs of the IL-6 receptor, PDGF A- and B-chains, and TGF beta 1 in megakaryocytic leukemic cells will be useful to clarify the mechanisms involved in the proliferation of megakaryocytic leukemic cells and fibroblasts in the bone marrow. Furthermore, we reviewed data showing that megakaryocytic erythroid, and mast cell lineages share the nuclear transcription factor known as GF-1 (NF-E1 or Erf-1). We suggest that characterization of megakaryocytic leukemia should be performed using monoclonal antibodies against erythroid, megakaryocytic and mast cell lineages.


[Effect of smoking on the development of various histological types of lung cancer]. The aim of this clinically controlled trial was to assess the effect of different smoking patterns on development of different histological types of lung cancer. The study group consisted of 1,432 subjects that died due to lung cancer in the years 1980-1987. 627 of these had the histological type of the cancer determined; 54% had squamous cell cancer, 24% small cell lung cancer (SCLC), 17% adenocarcinoma. The control group consisted of 1,343 subjects that died due to other causes. Medical and social history was taken from the families of the deceased. The results of the analysis demonstrate that lung cancer development is related to smoking although differences were seen in the different types of cancer. The calculated risk of a smoker developing lung cancer-squamous cell and SCLC was respectively 15.4 and 13.5 while for adenocarcinoma it was much lower--3.1. Important differences were seen in ex-smokers developing squamous cell lung cancer and SCLC. The risk of developing squamous cell lung cancer and SCLC in this group was 89% and 88%, and adenocarcinoma only 64%. This suggests that adenocarcinoma is related more to environmental factors than the other two types of lung cancer.


[Lung compliance in relation to frequency-dependent compliance (FDC) in men exposed to mixed air pollution]. 53 males (age 36.8 +/- 7.2 years) with occupational exposure to atmospheric pollutants (low content of silica, sulfur oxides, carbon oxide and heavy metals) for a mean duration of 12.1 +/- 4.8 years were studied. The majority smoked. Dynamic compliance was calculated from esophageal pressure measurements using an esophageal balloon with an electronic transducer and plethysmographic thoracic volume values (Siregnost FD 88 and FD 91S--Siemens). Dynamic compliance (Cdyn) was registered at a ventilatory rate of 15, 30 and 60/min. A significant correlation was found between Cdyn and ventilatory rate in the examined patients in comparison with the control. Cdyn15 = 73.3 +/- 18.8% Cst, Cdyn30 = 54.6 +/- 18.8% Cst, Cdyn60 = 37.4 +/- 14.9% Cst (control Cdyn15 = 85.17% Cst, p < 0.005, Cdyn30 = 82.6 +/- 11.4% Cst, p < 0.001, Cdyn60 = 67.4 +/- 15.8% Cst, p < 0.001). The percentage of abnormal individual Cdyn60 values in the studied group was significantly higher in comparison with the control (p < 0.005). The decrease of Cdyn60 was related to duration of occupational exposure, to mixed atmospheric pollution and history of smoking.


Effects of naltrindole and nor-binaltorphimine treatment on antinociception induced by sub-acute selective mu opioid receptor blockade. When administered repeatedly, in conjunction with hot plate testing, naloxone and naltrexone have the paradoxical effect of producing antinociception in rats and mice. Recently, we have found that the sub-acute selective blockade of mu opioid receptors leads to the development of antinociception and an augmentation of kappa receptor-mediated antinociception. In this study, acute delta/kappa antagonist treatment produced a significant decrease in paw lick latency in rats displaying antinociception induced by sub-acute mu blockade, however, the response level of these animals was still significantly above the baseline. In addition, rats receiving sub-acute combined mu and delta antagonist treatment took longer to develop an antinociceptive response than those treated with a mu antagonist alone. Sub-acute selective blockade of kappa or delta opioid receptors had no overall effect on paw lick latency during the course of 5 days of hot plate testing. The results indicate that delta receptor activity may play a role in the antinociception induced by sub-acute mu blockade. However, while delta antagonist treatment effected the expression, it did not completely attenuate the antinociception induced by sub-acute mu blockade suggesting that there is still a significant non-opioid component to this analgesic response. The results of a final experiment, in which acute delta antagonist treatment had no effect on antinociception induced by repeated systemic injections of naloxone, supported this hypothesis.


Characterization and partial purification from pheochromocytoma cells of an endogenous equivalent of scyllatoxin, a scorpion toxin which blocks small conductance Ca(2+)-activated K+ channels. This work describes the partial purification of a heat-stable peptide which has the same properties as the scorpion toxin, scyllatoxin, a specific blocker of one class of Ca(2+)-activated K+ channels: (i) it competes with [125I]apamin for binding to the same site, (ii) like apamin and scyllatoxin, it blocks the after-potential hyperpolarization in skeletal muscle cells in culture, (iii) like apamin and scyllatoxin, it contracts guinea-pig taenia coli relaxed by epinephrine, (iv) it cross-reacts with antibodies raised against scyllatoxin but not with antibodies raised against apamin.


Influence of oxidative stress on induced tolerance to ischemia in gerbil hippocampal neurons. We investigated whether reversible oxidative stress induced by the administration of the superoxide dismutase inhibitor, diethyldithiocarbamate, could induce tolerance to subsequent cerebral ischemia in gerbil hippocampal neurons. Mature male gerbils received intraperitoneal injections of diethyldithiocarbamate (1.0 g/kg), which led to reduced superoxide dismutase activity and increases in thiobarbituric acid-reactive substance in the brain. Cerebral ischemia was produced by occluding the bilateral common carotid arteries for 5 min, either 2 or 4 days after diethyldithiocarbamate injection. One week after ischemia, samples from each brain were stained with hematoxylin-eosin to evaluate ischemic neuronal damage in the hippocampal CA1 sector. Diethyldithiocarbamate treatment 4 days before ischemia had significant protective effects against cerebral ischemia, while diethyldithiocarbamate 2-day pretreatment and vehicle treatment failed to show neuroprotection. Biochemical examinations showed a clear induction of heat shock protein 72 and a significant increase in manganese-containing superoxide dismutase in the hippocampus in animals treated with diethyldithiocarbamate 4 days prior to ischemia. These results suggested that the oxidative stress caused by diethyldithiocarbamate could induced tolerance to ischemia in the gerbil brain, and that the increase in the biosynthesis of manganese-containing superoxide dismutase and heat shock protein 72 could provide a biochemical explanation of the tolerance induced under these conditions.


[EPR spin trapping of reactive oxygen products of the respiratory burst of phagocytes (use of EPR spectroscopy in biology and medicine. II)]. Respiratory burst during phagocytosis of human neutrophils is connected with the production of superoxide anion radical O2.-. This radical changes into further bioreactive oxygen products (especially H2O2 and .OH) which can be harmful to the organism. The principles of EPR spin trapping, the most reliable method for the study of short living free radicals, are presented. Advantages and problems of the study of O2.- and .OH by means of the 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) spin trap were assessed. Overproduction of O2.- (e.g. by chronic inflammation) can be treated with superoxide dismutase (SOD) or other drugs with SOD-like activity. Methods for studying such superoxide scavengers are reviewed. (Fig. 3, Tab. 2, Ref. 88.).


[Different localization of L-type and N-type activated calcium channels in the brain tissue cells in rabbits]. Postsynaptosomal, microsomal (HMF), and synaptosomal fractions were isolated from rabbit brain tissue according to two different protocols. The binding of 1,4-dihydropyridines and transport of 45Ca2+ indicated the presence of L-type of voltage operated calcium channels (VOCC) in the postsynaptosomal and microsomal membranes. The 200 kD protein, which bound 1,4-dihydropyridines and transported 45Ca2+, was identified as alpha-subunit of L-type VOCC. The authors further showed that after centrifugation of synaptosomal proteins into sucrose density gradient the fraction of proteins which sedimented in 1.10(1) mol/l sucrose was able to bind 125I-omega-conotoxin GVIA. The separation of these proteins in 6% PAGE resulted in proteins of Mw from 40 to 200 kD. The 170 kD protein extracted from PAGE bound omega-conotoxin along with 45-65 kD proteins, which are supposed to be subunits of the neuronal acetylcholine receptor. (Fig. 6, Ref. 15.).


Heterogeneity of bovine lactotransferrin glycans. Characterization of alpha-D-Galp-(1-->3)-beta-D-Gal- and alpha-NeuAc-(2-->6)-beta-D-GalpNAc-(1-->4)- beta-D-GlcNAc-substituted N-linked glycans. Lactotransferrin isolated from a pool of mature bovine milk has been shown to contain N-glycosidically-linked glycans possessing N-acetylneuraminic acid, galactose, mannose, fucose, N-acetylglucosamine, and N-acetylgalactosamine. The glycopeptides obtained by Pronase digestion were fractionated by concanavalin A-Sepharose affinity chromatography into three fractions: slightly retained (A), retained (B), and strongly retained (C). The structure of the glycans of the three fractions has been determined by application of methanolysis, methylation analysis, fast atom bombardment-mass spectrometry, and 1H NMR spectroscopy. Diantennary structures without GalNAc were present as partially sialylated and partially (1-->6)-alpha-L-fucosylated structures in Fractions A and B. Sequences containing alpha-D-Galp-(1-->3)-beta-D-Gal on the alpha-D-Man-(1-->6) antenna, and beta-D-GalpNAc-(1-->4)-beta-D-GlcNAc and alpha-NeuAc-(2-->6)-beta-D-GalpNAc-(1-->4)-beta-D-GlcNAc on the alpha-D-Man-(1-->3) antenna were characterized in the oligosaccharide-alditols obtained by reductive cleavage of Fraction B. A series of Man4-9-GlcNAc structures were identified in Fraction C after endo-N-acetyl-beta-D-glucosaminidase digestion. These results show that the structures of bovine lactotransferrin glycans are more heterogeneous than those of previously characterized transferrin glycans.


Chemical change involved in the oxidative-reductive depolymerization of heparin. A solution of hog intestinal heparin (average M(r) 12,000, anti-clotting activity 168 USP units/mg) in 0.2 M phosphate buffer (pH 7.2), was incubated in the presence of Fe2+ for 20 h at 50 degrees under an O2 atmosphere to yield oxidative-reductively depolymerized heparin (ORD heparin, average M(r) 3,000, anti-clotting activity 34 USP units/mg). Chemical analysis of the ORD heparin showed a 22, 26, and 14% loss of hexosamine, uronic acid, and N-acetyl group, respectively, but no remarkable loss of both total and N-sulfate groups. 1H and 13C NMR spectroscopic analysis indicated no decrease in the amount of L-iduronic acid 2-sulfate, but a marked loss of nonsulfated uronic acid (73 and 39% loss of D-glucuronic acid and L-iduronic acids, respectively, the sum of which corresponds to the chemically determined loss of total uronic acid). The results indicated that the ORD reaction of heparin proceeds essentially by destruction of monosaccharide units, except L-iduronic acid 2-sulfate residues, due to oxygen-derived free radicals, followed by secondary hydrolytic cleavage of the resulting unstable residues.


Complete 1H- and 13C-resonance assignments for D-mannooligosaccharides of the beta-D-(1-->2)-linked series released from the phosphopeptidomannan of Candida albicans VW.32 (serotype A). D-Mannooligosaccharides (dp 1 to > 17) were released by mild acid hydrolysis from the phosphopeptidomannan of a Candida albicans strain of A serotype (VW.32). Among these, mannooligosaccharides ranging from bi- to hepta-ose, which were obtained in appreciable amounts, were structurally investigated and found to belong to the beta-D-(1-->2)-linked series. The occurrence of such compounds has already been reported in other Candida albicans strains. The complete 1H- and 13C-resonance assignments for manno-tri- to manno-hepta-ose are reported and general rules applicable for the 1NMR spectrum analysis of linear mannooligosaccharide of the general structure, beta-D-Man p-(1-->2)-[beta-D-Man p-(1-->2)]n-beta-D-Man p are proposed.


Structural analysis of the carbohydrate chain of glycopeptides isolated from Robinia pseudoacacia seed lectins. Robinia pseudoacacia seeds contain lectins which are closely related. Pronase digestion of the dimeric and tetrameric lectins, RPA1 and RPA3, gave glycopeptides. The structure of the oligosaccharide was determined by 1H NMR spectroscopy and carbohydrate determination as alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->2)]-[alpha-D-Manp+ ++-(1-->6)]-beta- D-Manp-(1-->4)-beta-D-GlcpNAc-(1-->4)-[alpha-L-Fucp-(1-->3)] -beta-D-GlcpNAc - (1-->4)-Asn. It appears that the 34-kDa constitutive polypeptide of RPA1 contains 4-5 carbohydrate chains whereas the 30.5-kDa and 29-kDa subunits of RPA3 contain two and one oligosaccharide chains, respectively.


Oligosaccharide composition of the neurotoxin-responsive sodium channel of mouse neuroblastoma and requirement of sialic acid for biological activity. A glycoprotein, M(r) 200,000, which has the biological activity of the neurotoxin-responsive Na+ channel, was isolated from a clonal line of mouse neuroblastoma cells, N-18. The glycoprotein was purified to homogeneity in 18% yield by methods used to purify glycoproteins, which included metabolic labeling of the cells with L-[3H]fucose and binding of the radioactive glycoproteins to WGA- and lentil-Sepharose, and DEAE-cellulose. The glycoprotein has biological activity of neurotoxin-responsive ion flux when reconstituted into artificial phospholipid vesicles. This activity was shown to depend on the presence of sialic acid since treatment of the purified, reconstituted glycoprotein with Vibrio cholerae neuraminidase abolished the response to neurotoxins of 86Rb flux. The [3H]fucose-containing glycopeptides derived by Pronase digestion of the glycoprotein were characterized by affinity to immobilized lectins and contained di-, tri-, and tetra-antennary oligosaccharides in a ratio of 2:4:3. Most of the glycopeptides were sialylated as shown by binding characteristics to immobilized serotonin-Sepharose with and without neuraminidase. The structure of the diantennary oligosaccharides was elucidated by 500-MHz 1H NMR spectroscopy. The Con A-bound fraction contains alpha-NeuNAc-(2-->6)-bound group on the GlcNAc5' antenna and an alpha-NeuNAc-(2-->3)-bound groups on the GlcNAc5 antenna. An alpha-L-fucosyl group is (1-->6)-bound to the Asn core GlcNAc1 residue.


Separation of mucin oligosaccharide-alditols by high performance liquid chromatography on alkylamine-bonded silica columns. Effects of structural parameters. Forty five oligosaccharide-alditols, purified after reductive beta-elimination of human bronchial mucins, were analyzed by HPLC on alkylamine-bonded silica column (Lichrosorb-NH2). The comparison of their structural features and retention times permitted the extension of some previous findings. The chromatographic behavior of the oligosaccharide depends more on the accessibility of oligosaccharide hydroxyl groups than on the sugar composition. The use of this type of fractionation is very efficient for low-molecular-mass oligosaccharide-alditols but needs to be completed by a second chromatographic step for higher molecular-mass oligosaccharide-alditols.


Insensitivity of guinea pig ventricular delayed rectifier IK to intracellular trypsin: implications for channel structure and function. Intracellular application of proteolytic agents modifies the function of many voltage gated ion channels. The presence of a trypsin sensitive inhibitory domain in a channel protein may be important for G protein dependent activation. Guinea pig ventricular IK is modulated by a direct G protein pathway. The aim was to determine if guinea pig ventricular IK is also modified by intracellularly applied trypsin. Whole cell and excised inside out configurations of patch clamp were used to record IK from guinea pig ventricular myocytes before and after cytosolic application of trypsin (1 mg.ml-1). We used previously reported effects of trypsin on the L type calcium current (ICa) to monitor dialysis time and enzyme activity in whole cell experiments where IK and ICa were measured concomitantly. Addition of trypsin to the solution bathing the cytosolic face of excised membrane patches had no effect on the amplitude or kinetics of IK. When added to the pipette solution and introduced by cell dialysis, trypsin had no effect on whole cell IK, even when significant effects on the amplitude and kinetics of ICa were evident. Guinea pig ventricular IK is not enhanced or otherwise altered by intracellularly applied trypsin. Therefore direct phosphorylation independent enhancement of IK by guanine nucleotides cannot depend on interactions between G protein subunits and trypsin sensitive inhibitory channel domains. The lack of trypsin modification of cardiac ventricular IK suggests that the structure of the endogenous delayed rectifier K+ channel may be different than that of other voltage gated channels.


[Application of electron microscopy in the diagnosis of fine needle aspiration biopsies and tumorous pleural effusion]. Forty-five cases of fine needle aspiration biopsies of tumor and 9 cases of tumorous pleural effusion specimens were reviewed electron microscopically for diagnosis. Among them, electron microscopical diagnosis of 22 cases (40.7%) was valuable, and that of 28 cases (51.8%) was of no diagnostic significance. In 14 out of 22 cases (63.6%) the nature and origin of tumor were further confirmed by electron microscopy, and in 8 cases (36.4%) electron microscopical diagnoses were consistent with light microscopic diagnoses. It was shown that in cytological diagnosis of tumors, electron microscopy was superior to light microscopy in defining the nature and origin of tumors, and in differentiating neuroendocrine tumors, leukemia and small round cell tumors.


[Study on the expression of oncogenes in hepatocytes with hepatitis B virus infection]. The expression of oncogene N-ras mRNA and c-myc mRNA in paraffin embedded liver tissues from patients with hepatitis B virus (HBV) infection had been studied by in situ hybridization with biotin labeled probes. The results showed that the detection rates of N-ras mRNA and c-myc mRNA were 37.5% (24/64) and 29.7% (19/64) respectively in the liver tissues of 64 hepatitis B patients, 44.4% (16/36) and 47.2% (17/36) respectively in the liver tissues of 36 hepatocellular carcinoma (HCC) patients with HBV infection, and they were detected each in one of 6 normal liver tissue samples. No significant differences were observed among the three groups (P > 0.05). However, in HCC group, 11 out of 36 patients (30.5%) were positive for N-ras mRNA and c-myc mRNA simultaneously, which was higher than that in hepatitis B group (14.1%) (P < 0.05). None of the normal liver samples were N-ras mRNA and c-myc mRNA positive simultaneously. Further more, in the hepatitis group it was noticed that the detection rate of c-myc mRNA in HBV DNA positive cases (by in situ hybridization) was significantly higher than that in HBV DNA negative cases (P < 0.025).


[Immunocytochemical localization of human chorionic gonadotropin and placental lactogen in gestational trophoblastic neoplasms]. Preliminary observation on immunocytochemical localization of anti-HCG and anti-HPL in 49 patients with gestational trophoblastic neoplasms was studied. The findings were; (1) staining patterns to the two antibodies were different in cytotrophoblasts (CT), intermediate trophoblasts (IT), and syncytiotrophoblasts (ST) of the different types of trophoblastic tumor, (2)STs in tumors of all patients except one, showed positive staining of anti-HCG, and ITs in 17 cases of HM, 10 cases of IM and 1 case of GC were stained positively for anti-HCG; (3)STs in all of the 29 cases of HM, 14 cases of IM and 1 case of GC were positive for anti-HPL, ITs in 22 cases of HM, 11 cases of IM and 2 cases of GC were stained positively for anti-HPL. CTs in all tumors of the 49 patients were devoid of HCG and HPL. The results indicated that the production of HPL was found in well-differentiated cells and HCG in undifferentiated cells. The prognostic value of immunocytochemical localization of the two antibodies in trophoblastic tumors needs to be further clarified.


Analysis of the preventive action of ACTH on dexamethasone-induced adrenocortical atrophy in the rat. Adult female rats were treated for 4 or 6 days consecutively with dexamethasone (Dx; 100 micrograms kg-1 day-1) alone or with ACTH (100 micrograms kg-1 day-1) for 2, 4 or 6 days. After 2 days of ACTH administration, zona fasciculata cells increased in volume, and the blood concentration of corticosterone was raised. Basal corticosterone secretion by adrenal slices appeared to be enhanced by ACTH treatment only when calculating per adrenal pair (and not per unit wt of adrenals). A significant increase in the number of metaphase cells was observed after only 4 days of ACTH administration. It is suggested that (1) the first action of ACTH on Dx-suppressed rats is to induce the hypertrophy of adrenocortical cells; (2) the steroidogenic capacity of adrenocortical cells is directly proportional to their average volume; and (3) the stimulatory effect of ACTH on the proliferative activity of adrenocortical cells is subsequent to the stimulation of their specialized functions.


Detection of cellular ki-ras oncogene and Epstein-Barr viral DNA by polymerase chain reaction in situ. A newly established technique of polymerase chain reaction (PCR) in situ is reported. The process involved the use of the PCR technique to amplify the target gene and to generate the radiolabelled products which was used as a probe to hybridize the target gene in situ. Ki-ras oncogene in human pancreatic carcinoma cell line (PC-2) and EBV DNA in Raji cell line were detected in situ by this technique with encouraging results. This technique has the advantages of both PCR and in situ hybridization, i.e., high sensitivity, quick amplification and precise localization. It is a rapid, simple, economical and reliable method.


Histopathology and immunohistopathology of lymph nodes of the first autopsy with HIV positivity in China. Nineteen lymph nodes of a HIV-positive boy were studied histologically and immunohistologically. According to Stutte's classification of HIV-related lymphadenopathy, 84% of the lymph nodes were at the third or fourth stages in relation to clinical status ARC/AIDS. Lymph follicle atrophy, angiogenesis, histiocytic proliferation and destruction of the normal reticulum frame were observed. Immunohistochemical studies showed most of the remaining lymphocytes to be T cells and changes in the distribution of S-100 positive cells. Ki 1 positive cells existed mainly at the second stage. The significance of these changes is discussed.


Effect of verapamil on acute coxsackievirus B3 murine myocarditis. The effect of verapamil (Ver) on CVB3 murine myocarditis was investigated. It was found that Ver could aggravate the myocardial inflammation, increase the viral replication in myocardium, and raise mortality in mice with viral myocarditis when the drug was injected within the first 6 days after the CVB3 inoculation.


[Human papillomavirus type 16 and human cytomegalovirus in cervical carcinoma]. Using techniques of DNA-DNA dot blot hybridization, we examined 98 cervical specimens for the presence of human papillomavirus type 16 HPV-16 and human cytomegalovirus (HCMV) sequence and analysed the relationship between virus infection and various cervical diseases, age of patients, age at first coitus, age of first child birth, the number of pregnancy, use of oral contraceptives. The results showed that the rate of HPV DNA and HCMV DNA positivity in cervical carcinoma is significantly higher than that of non-carcinomatous tissue. In addition, the positivity correlates with age, at first intercourse, but not with age of first child birth, the number of pregnancy and use of oral contraceptives. These data suggested that HPV-16 and HCMV infection is associated with cervical carcinoma. Some cases of cervical erosion with HPV infection may lead to cervical. The high incidence of cervical carcinoma in women married early in life may be related to virus infection in adolescence. HPV acting with other synergistic factors, such as HCMV is considered to lead to the occurrence of cervical carcinoma.


Isolation and characterization of a DNA helicase from cytosolic extracts of calf thymus. A DNA helicase has been isolated from calf thymus tissue. The enzyme was enriched from crude cytosolic extracts by batchwise chromatography on phosphocellulose, followed by 35% ammonium sulfate precipitation, and subsequent chromatography on phenyl-Sepharose, single-stranded DNA cellulose, and AcA 44 gel filtration. The DNA helicase had a Stokes' radius of about 45 A and a sedimentation coefficient of 4.3 S. The most purified fractions contained three polypeptides with apparent molecular weights of 110, 65, and 34 kDa. UV crosslinking with radioactive dATP stained all three major polypeptides. The helicase catalyzed the unwinding of a DNA primer from a single-stranded DNA template in an ATP- or dATP-dependent manner. DNA unwinding was also observed with CTP or dCTP, but with reduced efficiency. The helicase translocated from 3' to 5' on the single-stranded template it was bound to. Relationships between this DNA helicase and other calf thymus helicases will be discussed.


The 3'-->5' exonuclease associated with HeLa DNA polymerase epsilon. The 3'-->5' exonuclease activity of highly purified large form of human DNA polymerase epsilon was studied. The activity removes mononucleotides from the 3' end of an oligonucleotide with a non-processive mechanism and leaves 5'-terminal trinucleotide non-hydrolyzed. This is the case both with single-stranded oligonucleotides and with oligonucleotides annealed to complementary regions of M13DNA. However, the reaction rates with single-stranded oligonucleotides are at least ten-fold when compared to those with completely base-paired oligonucleotides. Conceivably, mismatched 3' end of an oligonucleotide annealed to M13DNA is rapidly removed and the hydrolysis is slowed down when double-stranded region is reached. The preferential removal of a non-complementary 3' end and the nonprocessive mechanism are consistent with anticipated proofreading function. In addition to the 3'-->5' exonuclease activity, an 5'-->3' exonuclease activity is often present even in relatively highly purified DNA polymerase epsilon preparates suggesting that such an activity may be an essential component for the action of this enzyme in vivo. Contrary to the 3'-->5' exonuclease activity, the 5'-->3' exonuclease is separable from the polymerase activity.


Recognition of model DNA replication forks by the SV40 large tumor antigen. The ability of the SV40 large tumor antigen (T antigen), a DNA helicase, to bind to model DNA replication forks was tested. DNA fork molecules were constructed either from two partially complementary oligonucleotides or from a single oligonucleotide able to form a 'panhandle' structure. T antigen specifically recognized the two-strand fork in a reaction dependent on the presence of ATP, dATP, or non-hydrolyzable analogs of ATP. T antigen asymmetrically bound the two-strand fork, protecting from nuclease cleavage a fork-proximal region on only one of the two strands. The asymmetric binding is consistent with the 3'-->5' directionality of the DNA helicase activity of T antigen. An analogous region on the one-strand fork was also bound by T antigen, suggesting that T antigen does not require a free single-stranded end to load onto the fork. Use of chemically modified DNA substrates indicated that T antigen binding to the fork utilized important contacts with the DNA sugar-phosphate backbone.


Purification and functional characterization of bovine RP-A in an in vitro SV40 DNA replication system. The single-stranded DNA binding protein RP-A is required in SV40 DNA in vitro replication. The RP-A purified from calf thymus contains 4 polypeptides with molecular weights 70kDa, 53kDa, 32kDa, and 14kDa. The p70 subunit and its proteolysed form p53 are recognized by the monoclonal antibody 70C (Kenny et al. (1990)) and bind to ssDNA. The p70 and p32 subunits of bovine RP-A are phosphorylated by CDC2-cyclin B kinase. Bovine RP-A supports the origin dependent unwinding of SV40 DNA by T antigen. Furthermore, bovine RP-A can efficiently substitute for human RP-A in SV40 DNA replication in vitro. A modified blotting technique revealed that RP-A interacts specifically and directly with the p48 subunit of DNA polymerase alpha-primase complex.


Murine p53 inhibits the function but not the formation of SV40 T antigen hexamers and stimulates T antigen RNA helicase activity. We have characterized the effects of p53 on several biochemical activities of simian virus 40 (SV40) large tumor (T) antigen. While p53 induced a strong inhibition of the T antigen DNA helicase activity, surprisingly, its RNA helicase activity was stimulated. This supports the liklihood that the DNA and RNA helicase activities of T antigen reflect discrete functions. p53 did not significantly affect the ATP-dependent conversion of T antigen monomers to hexamers. However, the ability of these hexamers to assemble on a DNA fragment containing the viral origin was impaired by p53. Thus, these results suggest that p53 inhibits the function but not the formation of T antigen multimers. This conclusion was further supported by the observation that the addition of a purified p53:T antigen complex was as inhibitory as free p53 to the DNA helicase activity of free T antigen. Thus our data indicates that the targets of p53 inhibition are the functional units of T antigen, namely the hexamers.


Uracil in OriS of herpes simplex 1 alters its specific recognition by origin binding protein (OBP): does virus induced uracil-DNA glycosylase play a key role in viral reactivation and replication? We have recently demonstrated that mammalian uracil-DNA glycosylase activity is undetectable in adult neurons. On the basis of this finding we hypothesized that uracil, derived either from oxidative deamination of cytosine or misincorporation of dUMP in place of dTMP during DNA repair by the unique nuclear DNA polymerase present in adult neurons, DNA polymerase beta, might accumulate in neuronal DNA. Uracil residues could also arise in the herpes simplex 1 (HSV1) genome during latency in nerve cells. We therefore suggest a role for the virus encoded uracil-DNA glycosylase in HSV1 reactivation and in the first steps of DNA replication. We show here 1) that the viral DNA polymerase incorporates dUTP in place of dTTP with a comparable efficiency in vitro; 2) that virus specific DNA/protein interactions between the virus encoded origin binding protein and its target DNA sequence is altered by the presence of uracil residues in its central region TCGCA. Thus uracil, present in viral OriS or other key sequences could hamper the process leading to viral reactivation. Hence, HSV1 uracil-DNA glycosylase, dispensable in viral proliferation in tissue culture, could be essential in neurons for the "cleansing" of the viral genome of uracil residues before the start of replication.


Replication of SV40 minichromosomes in vitro. We operationally define two forms of SV40 minichromosomes, a 75S-form, prepared at low salt concentration, referred to as native minichromosomes, and a 50S-form, obtained after treatment with 0.5 M potassium acetate, the salt-treated minichromosomes. Both preparations of minichromosomes serve well as templates for replication in vitro. Their respective replication products are strikingly different: replicated native minichromosomes contain a densely packed array of the maximal number of nucleosomes whereas replicated salt-treated minichromosomes carry, on average, half of the maximal number. We conclude that in both cases parental nucleosomes are transferred to progeny DNA, and, in addition, that an assembly of new nucleosomes occurs during the replication of native minichromosomes. This is apparently due to the presence of a nucleosome assembly factor as a constituent of native minichromosomes that dissociates upon treatment with salt. We further show that preparations of minichromosomes usually contain significant amounts of copurifying hnRNP particles and SV40 virion precursor particles. However, these structures do not detectably affect the replication and the chromatin assembly reactions.


[Mitochondrial myopathy with peripheral neuropathy]. This paper reported mitochondrial myopathy with peripheral neuropathy of 2 cases. Both patients were males. Age: 22, 32. 11, 14 years respectively. They showed recurrent paralysis and asthenia of limbs. Case 1 was motor sensory neuropathy, whose EMG revealed neurogenic injury. Case 2 involved only the lower limbs, whose lactic acid level was increased. In both patients, muscle biopsy showed Ragged Red fibers and abnormal mitochondria. Sural nerve biopsy revealed moderate reduction in the number of mylinated fibers and chronic axonal degeneration without regeneration cluster and hypertrophic neuropathy. Electron microscopic examination showed the increase of Schwann cells and mitochondria, and abnormal mitochondria being less marded in Case 2. Mitochondrial myopathy with peripheral neuropathy and its pathogenesis were discussed.


Three new DNA helicases from Saccharomyces cerevisiae. At least six DNA helicases have been identified during fractionation of extracts from the yeast Saccharomyces cerevisiae. Three of those, DNA helicases B, C, and D, have been further purified and characterized. DNA helicases B and C co-purified with DNA polymerase delta through several chromatographic steps, but were separated from the polymerase by hydrophobic chromatography. DNA helicase D co-purified with Replication Factor C over seven chromatographic steps, and was only separated from it by glycerol gradient centrifugation in the presence of 0.2 M NaCl. All three helicases are DNA dependent ATPases with Km values for ATP of 190 microM, 325 microM, and 60 microM for DNA helicases B, C, and D, respectively. Their DNA helicase activities are comparable. They are 5'-3' helicases and have pH optima of 6.5-7 and Mg2+ optima of 1-2 mM. However, they differ in the nucleotide requirement for helicase action. Whereas all three helicases preferred ATP, dATP, UTP, CTP, and dCTP as cofactors, DNA helicase C also used GTP, but not dTTP. On the other hand, DNA helicase D used dTTP, but not GTP, and DNA helicase B used neither nucleotide as cofactor. These studies allowed us to conclude that DNA helicases B, C, and D are not only distinct enzymes, but also different from two previously identified yeast DNA helicases, the RAD3 protein and ATPase III.


[Later onset metachromatic leukodystrophy diagnosed by nerve biopsy]. Three cases of later onset metachromatic leukodystrophy in one family were reported. The brother is 32 years old, younger sister is 35 years old and the elder sister is 39 years old, who were normal as child without any family history of neurological disease. The three cases began their illness at about the age of 30 years old with dysarthria, progressive dementia, motor disturbance and numbness in the extremities. CT scan showed low density in the white matter of frontal, parietal lobes and around the ventricle. The written reports of CT scan were lacunar infarction in brother, multiple lacunar infarction in younger sister and Binswanger's disease in elder sister. Nerve biopsy showed myelinated fibers were decreased in number. Metachromatical materials were seen in and around the Schwann cell cytoplasm. Metachromatical materials were lamillar inclusions in granular matrix by electromicroscopic examination. So nerve biopsy is easy, safe and effective method to diagnose the uncertain pathogenic leukoence-phalopathy.


[Immunohistochemical study on X antigen of HBV (HBxAg) in primary hepatic carcinoma]. Specimens of 110 cases of primary hepatic carcinoma were obtained from the pathological Laboratory of the First Teaching Hospital of the 4th Military Medical University, Xi'an. P. R. China. Sections from formalin-fixed and paraffin-embedded material were stained for HBxAg by ABC method and for HBsAg and HBcAg by PAP method. Among the 110 cases of primary hepatic carcinoma, 64 (58.2%) showed HBxAg-positive reaction in tumor tissue, and 63 (78.8%) of 80 cases of noncancerous surrounding hepatic tissue displayed HBxAg positivity. Among 64 HBxAg-positive cases in tumor tissue, 15 (23.4%) were associated with HBsAg and/or HBcAg and among 63 HBxAg-positive cases in non-tumor tissue, 45 (71.4%) were associated with HBsAg and/or HBcAg. These findings suggested a close relationship between primary hepatic carcinoma and HBV infection. The high detection rate of HBxAg indicates very active expression of the integrated HBV-DNA genome in the host cells. However, how does HBxAg act in pathogenesis of hepatocellular carcinoma remains to be further investigated.


[Modulation effect of lithium on IL-2 and IFNr production by human peripheral blood mononuclear cells]. The immunomodulatory effect of lithium chloride was studied. The IL-2 and IFNr production by peripheral blood mononuclear cells(PBMC) were assayed in 52 normal subjects and 156 cancer patients. IL-2 and IFN-r levels in lymphoma patients were lower than in normal subjects. The IFNr level in the majority of patients with lung and esophageal cancers was abnormal but the IL-2 level was within the normal range. When lithium, IL-2 was incubated with PBMC in vitro, upregulation of IL-2 and IFNr production was observed in normal subjects and cancer patients. The IL-2 and IFNr levels were significantly increased by both lithium and rIL-2 but the effect of lithium was more potent. Lithium upregulated IFNr in 70% of patients with low levels whereas it did so in only 10-20% of patients with high levels. Therefore, lithium is a promising new immunoregulatory agent for clinical use.


[Histopathologic studies on whole organ giant section in breast cancer. II. Multicentricity and the chief primary lesion]. From April 1988 to January 1989, histopathologic studies on whole organ serial sections was done in 200 radical mastectomy specimens of female breast carcinoma. Results showed that the chief primary lesion measuring 0.5-1.0 cm or less in diameter had more multiple primary foci. With increasing size of the chief primary lesion, the incidence of multicentricity decreased. No significant relationship was found between the pathologic type of the chief primary lesion and multicentricity. But, in the non-invasive carcinoma, especially in carcinoma arising from the papillomatosis, invasive carcinoma of mucinous type and intraductal carcinoma with early infiltration were prone to develop multicentricity. The multicentricity in the second primary breast cancer was more common than in the first.


[Expression of type I and type III procollagen genes in human scirrhous carcinoma of breast by in situ hybridization]. Scirrhous carcinoma is characterized by remarkable amount of collagen fibrils, mainly Type I and Type III collagens. The origin of the collagens is still under debate. cDNA fragments of Type I and Type III procollagens were subcloned into Gemini pGEM vectors to synthesize the 35S-labeled cRNA probes. By in situ hybridization, we have found the fibroblasts surrounding the tumor cells and cords contained abundant Type I and Type III procollagen mRNAs which decreased with the distance of fibroblasts from the tumor cells. In all freshly prepared tissues, the tumor cells also contained significant pro alpha 1(I) and pro alpha 1(III) mRNAs, but no or little pro alpha 2(I) mRNA. The results indicated that Type I and Type III collagens in human scirrhous carcinoma of breast are mainly produced by fibroblasts. Tumor cells also participate in the disposition of collagen fibrils, probably Type I trimer and Type III collagens in accordance with what was observed in biochemical analysis and cell culture studies.


[Comparison of lectin receptor and carcinoembryonic antigen in the cancerous and non-cancerous tissues in the human breast]. ABC and immunohistochemical methods were used to compare the location of 8 lectin receptors (LRS) and carcinoembryonic antigen (CEA) in 100 cancerous and 56 non-cancerous tissues of the human breast. The results showed that the positive rates of peanutagglutinin (PNA) in the normal breast tissues, benign lesions and breast cancers were 38.1%, 37.1% and 73.7%, respectively (P < 0.005). The positive rates of Bardeiraea simpoicifolia receptors (BSL) in these 3 tissues were 14.3%, 17.1% and 75% (P < 0.005). The positive rates of CEA in these 3 tissues were 42.86%, 51.43% and 78.13% (P < 0.005). Analysis of the differences among the positive rates in cancerous tissues, normal breast tissue and non-cancerous tissues showed that CEA was not superior to BSL or PNA in its specificity in detecting breast cancers. Comparing the location of LRSs in the CEA positive specimens, we had discovered obvious differences in BSL and WGA in cancerous and non-cancerous tissues of the human breast. This implies that there may be a subtype CEA which is highly specific for breast cancers.


[Dynamic study on plasma antidiuretic hormone before and after surgery for lung cancers]. Plasma antidiuretic hormone (ADH) was assayed before and after surgery for lung cancers. The results showed that the plasma ADH in the control group was 11.6 +/- 4.8 pg/ml in contrast to higher levels in the lung cancer patients. The ADH level was highest in patients with small cell anaplastic cancer (SCAC), and in decreasing order, adenocarcinoma, mixed cell type carcinoma and lowest in squamous cell carcinoma. The ADH levels in all patients were reduced postoperatively from one week to three months when they approached the control level. One year later, ADH became elevated again in those who developed recurrence as compared with those clinically free of the disease. The difference was most significant in patients suffering from SCAC (P < 0.05-0.001). The authors believe that ADH assay may be useful in the diagnosis, assessment of treatment and monitor or prognosis in lung cancers.


Activity of different antiviral drug combinations against human cytomegalovirus replication in vitro. The effects of different antiviral drug combinations on the replication of various human cytomegalovirus (CMV) strains in human embryonic lung (HEL) fibroblasts were evaluated. HPMPC combined with either ganciclovir, foscarnet or acyclovir showed additive to synergistic inhibition of CMV replication. Combinations of zidovudine with HPMPC, ganciclovir, foscarnet or acyclovir also resulted in additive to synergistic inhibition of CMV replication. Synergism tended to be higher for the clinical CMV isolates than for the reference strains AD-169 and Davis. Suppression of CMV replication was obtained at lower drug concentrations when the drugs were combined than when the drugs were used alone. At the highest drug concentrations used in the antiviral activity experiments, neither drug alone nor its combination suppressed host cell growth. If higher drug concentrations were used, zidovudine increased the inhibitory effects of ganciclovir, acyclovir and foscarnet but not of HPMPC, on cell proliferation. Use of combinations in the therapy of CMV infections may be considered to enhance drug efficacy, to reduce toxicity and, possibly, to diminish the risk of emergence of drug-resistant virus strains.


[Incidence of cylindroma in rural dental practice]. In connection with a case that was misdiagnosed and has been mistreated for 1.5 years, the authors warn that behind a long, uncertain inflammation there might be a tumour as well. They strongly emphasize that each dental examination should be an oncological one at the same time thus helping the dentist in the early recognition of the tumorous disease. The relevant national and international literature is also described in connection with the actual case.


Budd-Chiari syndrome as the primary manifestation of a fibrolamellar hepatocellular carcinoma. An 18-year-old female patient was admitted with ascites, right upper abdominal tenderness and peripheral edema. Angiography showed complete occlusion of the vena cava inferior up to the level of the right atrium. By open heart surgery, masses of thrombotic material were pulled out of the v. cava inferior/vv. iliacae which histologically contained tumor cell populations consistent with a hepatocellular carcinoma. Celiacography showed a highly vascularized tumor in the right hepatic lobe. Histologically, it proved to be fibrolamellar subtype hepatocellular carcinoma.


An epidemic of acute haemorrhagic conjunctivitis caused by coxsackie A24 variant. An epidemic of acute haemorrhagic conjunctivitis (AHC) caused by a variant of coxsackie A24 (cox A24) occurred in Delhi during August to September 1988. Cox A24 antigen was detected by indirect immunofluorescence (IFA) in conjunctival cell smears of 13 of the 38 (34.2%) patients studied. Virus was isolated from conjunctival swabs in 11 (28.9%) patients and all isolates were neutralized by cox A24 antiserum. Five virus strains sent to Virology Division of Centres for Disease Control, Atlanta, USA, were confirmed as cox A24 variant. Enterovirus type 70 (EV70) was not demonstrable either by IFA or neutralization tests. Conjunctival swabs from 10 healthy laboratory controls did not show any evidence of EV70 or cox A24 virus or their antigens.


Susceptibility status of five species of Japanese encephalitis vectors to insecticides from Kolar district, Karnataka. Susceptibility tests were conducted on the adults of five species of mosquito vectors of Japanese encephalitis (JE) viz., Culex tritaeniorhynchus, C. vishnui, C. pseudovishnui, C. gelidus and C. fuscocephala from Kolar district, Karnataka during 1990-91 against organo chloride compounds (DDT 4%, dieldrin 4%), organo phosphate compounds (malathion 5%, fenitrothion 1.0%), carbamate (propoxur 0.1%) and pyrethroid (deltamethrin--OMS 0.025%). All the five species were found susceptible to malathion. C. tritaeniorhynchus was resistant to DDT, dieldrin and fenitrothion; C. vishnui was also susceptible to fenitrothion and propoxur; C. pseudovishnui was resistant to dieldrin but it was susceptible to fenitrothion and propoxur. C. gelidus and C. fuscocephala were susceptible to dieldrin, fenitrothion and propoxur. Deltamethrin did not exhibit a good adulticidal effect except for C. pseudovishnui and C. fuscocephala. However, verifications are required to determine the susceptibility status of C. vishnui, C. pseudovishnui, C. gelidus and C. fuscocephala against DDT, C. tritaeniorhynchus against propoxur and C. vishnui against dieldrin.


Haematological and erythrocyte membrane changes induced by amiodarone, in rats. The effect of Amiodarone (AD), a cationic amphiphilic drug, on erythrocytes and leucocytes was studied. Treatment of rats with AD showed a significant decrease in the red cell count and the level of Hemoglobin. Amiodarone altered the fluidity of the erythrocyte membrane followed by a decrease in the activities of membrane bound enzymes like (Na+, K+)-ATPase, Acetylcholine esterase and NADH dehydrogenase. A slight increase in the leucocyte count was also observed in the treated animals.


The apical seal of root canal sealing cements using a radionuclide detection technique. The aim of this study was to evaluate the apical seal obtained with various root canal sealing cements using a new method based on the use of a radionuclide and an external detection technique. A total of 150 maxillary incisors and canines, which had been kept in saline solution, were used. The root canals were instrumented with a stepback technique and circumferential filing. Six experimental groups and two control groups were randomly formed. Each experimental group was obturated by a lateral condensation technique with gutta-percha points and a different sealing cement (two based on zinc oxide-eugenol cement, two based on resins and two on calcium hydroxide); the positive control used gutta-percha without sealing cement, while in the negative control the apex was covered with nail varnish, leaving the root canal empty. The apical leakage was measured using an external detection technique after submerging the root apices in a solution containing the radioisotope metastable 99Tc. No leakage was observed in the negative control group. There was a large difference between the leakage observed in the positive control group and the experimental groups. The best seal was obtained using Sealapex cement, which differed significantly from AH26, Tubli-Seal and Diaket; there was no significant difference between the latter. The poorest results were obtained with Endomethasone and CRCS; there was a significant difference between these and the previous three sealing cements.


Tissue Na+K+ activated adenosine triphosphatase in retinol deficient albino rats. The effect of retinol deficiency on Na+K+ ATPase was studied. Retinol deficient rat kidney, liver and spleen revealed a two to three-fold increase in ouabain sensitive Na+K+ ATPase activity in relation to controls. The activity in the controls could be stimulated more by concanavalin A than in the deficient group. The membrane-bound activity in the deficient group was more susceptible to freezing and thawing than the controls. Detergents could enhance the activity in both the groups to different levels. The enzyme revealed a high Km and Vmax for ATP and the cholesterol: phospholipid ratio was markedly decreased in the deficient group.


The relationship between endogenous oestradiol and vitamin D3 metabolites in serum and follicular fluid during ovarian stimulation for in-vitro fertilization and embryo transfer. The present study was undertaken to examine the effect of circulating oestradiol on serum levels of 25-hydroxyvitamin D3 (25-OHD3), 24,25-dihydroxyvitamin D3[24,25-(OH)2D3], and 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] during gonadotrophin-induced ovarian stimulation in 10 healthy women undergoing in-vitro fertilization and embryo transfer (IVF). The presence of these metabolites in the follicular fluid was also investigated. Plasma oestradiol increased from 25 +/- 3.2 (mean +/- SE) pg/ml before initiation of treatment to 2563 +/- 328 pg/ml on the day of injection of human chorionic gonadotrophin (HCG) and 1641 +/- 299 pg/ml on the day of ovum retrieval (P < 0.01). Serum levels of 1,25-(OH)2D3 increased from 32.0 +/- 1.9 (mean +/- SE) pg/ml to 46.6 +/- 8.1 and 48.5 +/- 7.7 pg/ml (P < 0.05) on the day of HCG and ovum retrieval, respectively. No changes in blood levels of 25-OHD3 and 24,25-(OH)2D3 were found. The presence of vitamin D metabolites in follicular fluid is documented herein for the first time. All three metabolites were present in the follicular fluid but were significantly lower than in the concurrent serum (P < 0.01). A highly significant correlation was found between serum and follicular fluid levels: r = 0.787, P < 0.001 for 1,25-(OH)2D3; r = 0.738, P < 0.01 for 25-OHD3; and r = 0.751, P < 0.01 for 24,25-(OH)2D3. Our results suggest that raised levels of circulating oestradiol during gonadotrophin-induced ovarian stimulation are associated with a significant increase of serum 1,25-(OH)2D3.


Beta-endorphin concentration in the femoral and spermatic venous blood of males affected by varicocele. Several studies in the rat indicate that opioid peptides produced in the testicular interstitial compartment can affect events in the tubular compartment. For example, it is thought that some specific functions of Sertoli cells, such as androgen-binding protein production are decreased by a paracrine mechanism. In this study ACTH beta-endorphin and cortisol were measured in the femoral and spermatic venous blood drawn from 18 patients affected by varicocele during catheterization for venous occlusion. The results showed the absence of a significant secretory gradient of beta-endorphin in the human testis and also demonstrated that this opioid is circulating at picomolar concentrations within human testis under stress conditions.


Incidental adrenal nodules: association with exaggerated 17-hydroxyprogesterone response to adrenocorticotropic hormone. The etiology of incidentally discovered, nonfunctional adrenal nodules was evaluated by using the 17-hydroxyprogesterone (17-OHP) response to synthetic adrenocorticotrophin (cosyntropin) (ACTH) administration. Patients who were discovered to have adrenal nodules and age-matched volunteers were studied. A total of 12 patients with adrenal nodules and 10 control subjects were studied. None of the patients with adrenal nodules had any evidence of hormonal hypersecretion consistent with pheochromocytoma, Cushing's syndrome or hyperaldosteronism. All subjects had serum 17-OHP and cortisol responses measured at baseline and at 30 and 60 min following the intravenous administration of 250 micrograms of ACTH. Baseline 17-OHP levels in patients with adrenal nodules were not significantly different from those of the normal controls (adrenal nodules 17-OHP: 75 +/- 13 vs control 68 +/- 11 ng/dl). After stimulation with ACTH, both 30 min and 60 min 17-OHP levels in patients with adrenal nodules (322 +/- 47 and 361 +/- 54 ng/dl, respectively) were significantly elevated over the responses seen with the controls (169 +/- 29 ng/dl at 30 min, p < 0.015, and 158 +/- 20 ng/dl at 60 min, p < 0.004). Baseline and post-ACTH serum cortisol levels were similar in both groups. Out of these twelve patients with adrenal nodules, nine were reevaluated twelve months later. In this group the basal 17-OHP remained comparable to normal levels (72 +/- 8.4 ng/dl) whereas the post-ACTH levels still remained exaggerated (30 and 60 min values 327 +/- 37 and 373 +/- 39 ng/dl).(ABSTRACT TRUNCATED AT 250 WORDS)


Adrenocorticotropic hormone and beta-endorphin concentrations in the inferior petrosal sinuses in Cushing's disease and other pituitary diseases. Aim of the present study was the evaluation of ACTH and beta-endorphin-like-immunoreactivity (beta-ELI) in the inferior petrosal sinuses (IPS's) and in the peripheral blood of patients with Cushing's disease (Group 1), with GH- or PRL-secreting adenomas or nontumoral hyperprolactinemia (Group 2). These patients had undergone selective and bilateral simultaneous IPS sampling for diagnostic purposes or for neurosurgical indications. In the patients of Group 1, ACTH and beta-ELI levels were higher in the IPS ipsilateral than in the contralateral to the adenoma and in the periphery (p < 0.001). In the patients of Group 2 ACTH and beta-ELI levels were higher in the IPS's than in the peripheral blood (p < 0.001) and, in the 9 patients with GH- or PRL-secreting adenomas, they were higher in the IPS ipsilateral than in the contralateral to the adenoma and in the periphery (p < 0.05). A significant correlation exists between ACTH and beta-ELI in the periphery (p < 0.01; r = 0.72), in the IPS ipsilateral (p < 0.05; r = 0.54) and contralateral (p < 0.01; r = 0.66) to the adenoma in Group 1, but not in Group 2. In conclusion, higher beta-ELI levels were detected in the IPS's than in the peripheral blood not only in patients with Cushing's disease but also in those with other pituitary diseases not involving ACTH secretion. The absence of correlation between ACTH and beta-ELI in patients not bearing Cushing's disease suggests that in these conditions corticotrophs release ACTH and beta-endorphin in an independent manner.


Value of serum dehydroepiandrosterone sulfate assay in the evaluation of pituitary-adrenal insufficiency after pituitary adenomectomy. The value of dehydroepiandrosterone sulfate (DHEA-S), a specific marker of adrenal androgen production, in the assessment of clinical states of hypercortisolism and hypocortisolism has been suggested. Since the way to simply test for ACTH reserve in patients (pts) with pituitary tumors after adenomectomy is not standardized, in this study serum DHEA-S concentration was measured in order to establish whether its determination might be a sensitive index of ACTH deficiency. Serum DHEA-S concentration was evaluated in 29 pts with hypothalamic-pituitary tumors (16 females, 13 males, aged 20-70 yr), 14 of whom had GH-secreting adenomas, 13 nonfunctioning adenomas, 1 prolactinoma and 1 craniopharyngioma. Serum DHEA-S and cortisol (F) levels were determined both before and every day for 8 days after pituitary adenomectomy. Before surgery in all pts mean DHEA-S and F basal values were 3.57 +/- 0.42 mumol/L and 391.8 +/- 29.0 nmol/L, respectively. Eight out of 29 pts showed reduced DHEA-S levels (0.85 +/- 0.19 mumol/L), which remained lower than normal in the postsurgical period; on the contrary, F levels were reduced in only 2 and 3 cases before and after surgery, respectively. In 3 other pts DHEA-S levels were normal before surgery and then were low in the postoperative period, while serum cortisol remained normal in all cases. In most of these patients, the finding of impaired responses to hypothalamic-pituitary-adrenal tests, together with a reduced corticosteroid urinary excretion, confirmed the existence of a secondary hypoadrenalism and the necessity for an adequate replacement therapy.(ABSTRACT TRUNCATED AT 250 WORDS)


Structure-activity relationship between the 3D distribution of the electrophilicity of sugar derivatives and their cytotoxic and antiviral properties. The cytotoxic activities of a series of sugar derivatives bearing electrophilic groups (1-cyanovinyl, 4-cyanochromen-2-yl and 3-nitrochromen-2-yl) have been correlated with their electrophilic properties. To this end, an electrophilic index was defined as an isovalue surface where the interaction energy with an incoming model nucleophile (H-) was equal to a predefined value. This index, calculated from extended Hückel wave functions, allows one to quantify the electrophilic character of the substrates and to describe its spatial localization within the molecular volume (at Michael acceptor sites or on other parts of the molecules). Only sugars for which Michael acceptor reactivity was predicted were retained, and they were subdivided into two groups: those showing antiviral activity against a retrovirus and those devoid of such activity. Under these conditions, good correlations between cytotoxic activity and electrophilic reactivity--positive for the first group, negative for the second--were found. In addition, the ratio electrophilicity/sum of the absolute value of the dipole plus its projection along the principal axis of inertia, Z, of the molecule allows one to predict to which of these groups a sugar derivative belongs.


Effect of dietary fat and fiber on fecal flora, bacterial metabolites, and fecal properties in Japanese volunteers. The effects of dietary fat and dietary fiber (DF) levels in diet on fecal flora, activities of three fecal enzymes, putrefactive metabolites, fecal mutagenicity and fecal properties were studied in eight healthy volunteers. They were given low fat and low DF diet (LF: fat energy ratio was 13.9%, and DF intake was 9.0 g/day) for 10 days, high fat and low DF diet (HF: fat energy ratio was 52.7%, and DF intake was 7.1 g/day) for 10 days, and high fat and high DF diet (HFF: fat energy ratio was 52.0%, and DF intake was 24.8 g/day) for 10 days. No change of fecal flora at the bacterial group level was observed throughout the experimental period, except that the population of lactobacilli showed a tendency to increase in HF period. Fecal activities of beta-glucuronidase, beta-glucosidase and nitroreductase and some putrefactive products were unchanged between LF and HF, while these values decreased in HFF period. No significant change of fecal properties was observed between LF and HF, while by HFF supplementation fecal weight increased and fecal pH value was lower than that in LF and HF. Excretions of iron, zinc and calcium in feces did not increase by high DF supplementation.


Metabolism of arachidonic, eicosapentaenoic, and docosahexaenoic acids in HepG2 cells and rat hepatocytes. The metabolism of arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) was examined in HepG2 cells, a human hepatoma cell line, and rat hepatocytes. The AA level in HepG2 cells was lower than in rat hepatocytes and incorporation of AA into HepG2 was also smaller than into rat hepatocytes. Both cells could not increase the level of cellular DHA by the addition of exogenous 22:5 (n-3); whereas, rat hepatocytes, but not HepG2 cells, increased the levels of AA from 20:3 (n-6) and EPA from 20:4 (n-3). In both cells, retroconversion of AA to 20:3 (n-6) occurred, but EPA was not retroconverted to 20:4 (n-3). These results suggested that the levels of AA and DHA in both types of cells, were regulated more severely than EPA and that the activity of fatty acid desaturation might be different between n-6 and n-3 families.


Franz Volhard Lecture. Renin-angiotensin system: a dual tissue and hormonal system for cardiovascular control. The renin-angiotensin system is both a circulating and a local tissue hormonal system. All components of the renin-angiotensin system have been found in important cardiovascular structures, including the heart, vessels, brain, kidney and adrenal gland. The angiotensin converting enzyme (ACE) is the final step in the enzymatic cascade of the renin-angiotensin system, which converts angiotensin in both the circulation and the tissues. ACE is predominantly an ectoenzyme with a bilobed homodimer extracellular portion, a short transmembrane span and a small intracellular extension. ACE contains two catalytic sites, one on each lobe. There is evidence that these catalytic sites may differ in several properties and may have different conformational requirements. This raises the possibility that there may be different endogenous substrates for each site and it may be feasible to design more specific ACE inhibitors that inhibit only one catalytic site. CARDIOVASCULAR ROLE OF LOCAL RENIN-ANGIOTENSIN SYSTEM: The physiological cardiovascular functions of the tissue renin-angiotensin system may include regulation of regional blood flow, modulation of local sympathetic activity and interaction with the endothelium. There is increasing evidence that the local renin-angiotensin system may be involved in the maintenance of cardiovascular structure and repair. ACE is increased in many forms of vascular and cardiac hypertrophy and the administration of ACE inhibitors has led to regression of hypertrophy. Many of the beneficial effects of ACE inhibitors may be due to inhibition of the local renin-angiotensin system. The local renin-angiotensin system may also be involved in the response to injury and in the inflammatory response. ACE is known to be increased in granulomas, it is expressed on monocytic macrophages and fibroblasts and many of the peptides involved in the inflammatory response (bradykinin, substance P, enkephalins) can act as ACE substrates. Following an acute myocardial infarct, ACE is increased in the myocardial scar and in the hypertrophying cardiac muscle. This provides a possible mechanism for the beneficial effect of ACE inhibitors in postmyocardial infarction trials. NON-CARDIOVASCULAR SYSTEM: Neither the function of the renin-angiotensin system in the brain and non-cardiovascular tissues nor its role in the pathophysiology of hypertension are known as yet.


Vascular tissue renin-angiotensin system in hypertensive humans. To obtain direct evidence for and evaluate functional aspects of the vascular tissue renin-angiotensin system. The local release of renin and angiotensin II was studied in forearm and coronary vascular beds of hypertensive hospitalized patients. The interaction between the vascular tissue renin-angiotensin system and sympathetic neurotransmission was also evaluated. Local beta-adrenoceptor stimulation released active and inactive renin and angiotensin II from forearm vessels, indicating the presence of a vascular tissue renin-angiotensin system in essential hypertensives. Local production of active renin and angiotensin II was closely correlated with circulating renin levels, suggesting that this vascular tissue renin-angiotensin system is at least partly dependent on uptake of renin from the circulating renin-angiotensin system. The local active renin and angiotensin II production was rapidly exhausted; this might represent a short-term control mechanism. Locally generated angiotensin II increased sympathetic vasoconstriction through the presynaptic release of noradrenaline and this effect was mediated by beta-adrenoceptor stimulation. Infusions of adenosine promoted the release of active renin and angiotensin II from the forearm and the coronary vessels.


Ouabain, digitalis-like factors and hypertension. To review the evidence that ouabain and other digitalis-like factors are present in the human circulation under normal circumstances and in various disorders of fluid and electrolyte balance that are associated with hypertension. Recent evidence on a number of ouabain-related issues includes (1) evidence for the existence of inhibitors of sodium pumps in mammalian plasma, (2) the identification of one of these factors as ouabain, (3) measurements of plasma levels of ouabain in man, (4) evidence that ouabain causes chronic hypertension in rats and is associated with human hypertension, and (5) data on some probable mechanisms that may mediate the pressor effect. The available data support the novel hypothesis that ouabain is an endogenous circulating agent in man and other mammals and is likely to influence long-term blood pressure levels.


Na+/H(+)-exchange in A6 cells: polarity and vasopressin regulation. We have analyzed the mechanism of Na(+)-dependent pHi recovery from an acid load in A6 cells (an amphibian distal nephron cell line) by using the intracellular pH indicator 2'7'-bis(2-carboxyethyl)5,6 carboxyfluorescein (BCECF) and single cell microspectrofluorometry. A6 cells were found to express Na+/H(+)-exchange activity only on the basolateral membrane: Na+/H(+)-exchange activity follows simple saturation kinetics with an apparent Km for Na+ of approximately 11 mM; it is inhibited in a competitive manner by ethylisopropylamiloride (EIPA). This Na+/H(+)-exchange activity is inhibited by pharmacological activation of protein kinase A (PKA) as well as of protein kinase C (PKC). Addition of arginine vasopressin (AVP) either at low (subnanomolar) or at high (micromolar) concentrations inhibits Na+/H(+)-exchange activity; AVP stimulates IP3 production at low concentrations, whereas much higher concentrations are required to stimulate cAMP formation. These findings suggest that in A6 cells (i) Na+/H(+)-exchange is located in the basolateral membrane and (ii) PKC activation (heralded by IP3 turnover) is likely to be the mediator of AVP action at low AVP concentrations.