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PubMed1984

Uptake and metabolism of thyroid hormones by the rat foetus in early pregnancy.

Pregnant rats were injected with trace amounts of [125I]thyroxine [( 125I]T4) or [125I]-tri-iodothyronine [( 125I]T3). Maternal blood, organs and foetuses were removed 1 and 4 h later, homogenized and tri-chloroacetic acid added to precipitate radiolabelled iodothyronines. An hour after injecting [125I]thyroxine, 9-10 day old foetuses contained 21% of the radiolabel found in the same weight of plasma whereas by 13-14 days they contained 0.6%. An hour after injection of [125I]tri-iodothyronine, 9-10 day old foetuses contained 54% of the radioactivity present in the same weight of plasma. When related to tissue protein, the radiolabelled iodothyronine content in 9-10 day old foetuses was comparable with that in maternal brain, heart or ovary. De-iodination of [125I]thyroxine in 9-10 day old foetoplacental units was equal to that in maternal liver but greater than that in brain or heart. It is concluded that substantial amounts of thyroxine and tri-iodothyronine enter the rat foetus in early pregnancy but thyroxine uptake may be minimal in later pregnancy.

Amniotic Fluid↗
PubMed1997

Umbilical cord 'pseudo-vasculitis' following second trimester fetal death: a clinicopathological and immunohistochemical study of 13 cases.

Amniotic fluid bacterial infection is an occasional cause of second trimester septic abortion. We describe an autolysis-related histological artifact, umbilical cord 'pseudo-vasculitis', which can erroneously implicate amniotic bacterial infection in fetal death. Clinicopathological features of 13 second trimester fetal deaths with umbilical cord pseudo-vasculitis are reported. In four cases (31%), an incorrect pathological diagnosis of umbilical vasculitis had initially been rendered. Umbilical cords from five cases of pseudo-vasculitis and one comparison fetus (18-week septic abortion with true umbilical vasculitis), were studied with chloroacetate esterase and with immunohistochemical staining for myeloperoxidase, muscle-specific actin (HHF35) and smooth muscle actin. Histologically, umbilical pseudo-vasculitis exhibited numerous small, rounded, degenerating cells with irregular, multilobed nuclei (closely resembling neutrophils) located within the umbilical vessel wall. Immunohistochemical studies demonstrated that all cells resembling neutrophils were of smooth muscle origin. Moderate to severe fetal autolysis was present in all cases of umbilical pseudo-vasculitis, suggesting that this finding represents autolysis of umbilical vascular smooth muscle secondary to post moderate fetal retention. Vascular smooth muscle in other fetal and placental locations did not demonstrate the finding, suggesting that this striking degenerative artifact of smooth muscle is restricted to the umbilical cord.

Actins↗
PubMed1998

Induction of human leukaemic mast cell differentiation by fibroblast supernatants, but not by stem cell factor.

In order to explore the potential existence of human mast cell growth factors other than stem cell factor (SCF), we have compared SCF to L-cell fibroblast supernatants (LCS) during in vitro mast cell differentiation, using human leukaemic mast cells (HMC-1 cells) which contain a gain-of-function mutated SCF receptor (c-Kit) as model. At baseline, cells exhibited an immature phenotype, with <25% being metachromatic or chloroacetate esterase, tryptase and FcepsilonRIalpha positive. Intracellular levels of histamine, tryptase, TNF-alpha and chymase were low, whereas 83% of cells were c-Kit positive. During a 10 day culture with 30% LCS, a significant, time-dependent increase of all mast cell markers, except for chymase and c-Kit, was observed at the protein and for tryptase and FcepsilonRIalpha also at the mRNA level. Cytoplasmatic granulation and stimulated histamine and leukotriene C4 release were increased as well. In contrast to LCS, rhSCF induced none of these changes in HMC-1 cells. On Sephadex G100 fractionation of LCS, HMC-1 cells increased tryptase activity with fractions between 40 and 60, and below 10 kDa, away from the SCF peak. These data show that HMC-1 cells fail to differentiate in response to SCF and that in addition to SCF, LCS contains other human mast cell growth factors.

Animals↗
PubMedDate not supplied

Enzyme-histochemical detection of a chymase-like proteinase within bovine mucosal and connective tissue mast cells.

The presence of chymase-like proteinase in bovine mast cells was investigated by an enzyme-histochemical technique (naphthol-AS-D-chloroacetate as substrate) in normal skin, primary bronchus, lung and duodenum. The counts and distribution of chymase-positive and toluidine blue-positive mast cells were compared by means of successive staining. Mast cells with chymase-like activity were detected in all areas, but their proportion was greater in connective than mucosal tissues, with the exception of the skin. These results contrast with those obtained in rodents, in which chymase-like proteinases are detected in all tissues and also in all mast cells. Bovine mast cells are closer to those of human beings, in which chymase-containing mast cells predominate in connective tissues, including skin. The results suggest that more than one chymase subset is present, at least in duodenum. The possible occurrence of dual-specific chymase mast cells, as in other ruminants, is discussed.

Animals↗
PubMed2000

Synthesis and analgesic activity of some novel 2-substituted 1,3,4-thiadiazolo

An ecofriendly synthesis for 1,2,3,4,5,6,8-octahydro- 3-amino-2-thioxo-benzothieno[2,3-d]pyrimidin-4-one (7A, B) has been developed. A series of hitherto unreported compounds (2a-i, 3a-c) have been synthesized by treating 3-Amino-2-mercaptopyrimidinones (7A, B) with one carbon donors like chloroacetyl chloride or chloroacetic acid and subsequently replacing the chloro group by various nucleophiles. Compound 2f was successfully synthesized by an alternate route. All the new compounds were characterized by elemental and spectral analyses. They were screened for analgesic activity in mice. Compounds 2a, b, 3a, b, and 2e, showed very good activity.

Journal Article↗
PubMed1999

Synthesis and evaluation of anti-inflammatory activity of some thiazolo[3,2-b]-1,2,4-triazole-5(6H)-ones and their Michael addition products.

Thiazolo[3,2-b]-1,2,4-triazole-5(6H)-ones (4-10) were obtained in a one step synthesis by heating 3-aryl-5-mercapto-1,2,4-triazoles (3a-d) with chloroacetic acid and appropriate aromatic aldehyde in acetic acid and acetic anhydride in the presence of anhydrous NaOAc. Michael type addition of cyclic secondary amines (N-methylpiperazine, piperidine) to 4-10 gave 2-phenyl-6-(alpha-aminoarylmethyl)thiazolo[3,2-b]-1,2,4-triazole-5 -ols (4a-10b). The structures of the compounds were confirmed by spectral and elementary analysis. The compounds synthesized in previous and present studies were investigated for their anti-inflammatory activities.

Animals↗
PubMed2004

Granulocyte colony-stimulating factor synergistically augments 1,25-dihydroxyvitamin D3-induced monocytic differentiation in murine bone marrow cell cultures.

In a series of studies, we have reported that 1,25-dihydroxyvitamin D (3), a known stimulator of monocytic differentiation, primes bone marrow progenitor cells or promyelocytic HL-60 cells to the actions of several factors involved in both monocytic and granulocytic differentiation. In the present study, we have further examined the combinational effects of 1,25-dihydroxyvitamin D (3) and the other inducer of granulopoiesis, granulocyte colony-stimulating factor, on non-fractionated native murine bone-marrow cell culture. Over 6 days of treatment, human granulocyte colony-stimulating factor sustained cell viability, increased the size of small rounded non-adherent cells, and induced granulocytic differentiation, while 1,25-dihydroxyvitamin D (3) decreased cell viability, promoted the development of large adherent flattened cells, and upregulated some monocytic differentiation markers. Combining these two factors over 6 days synergistically upregulated phagocyte activity, membrane-bound interleukin-1alpha, NAD(P)H oxidase, monocytic Mac-1, and non-specific esterase. Similar effects were observed in successive treatment with granulocyte colony-stimulating factor followed by 1,25-dihydroxyvitamin D (3), but successive treatment in reverse order was somewhat less effective. No combinational treatment upregulated granulocytic lactate dehydrogenase, Gr-1, or chloroacetate esterase to as great an extent as was obtained with granulocyte colony-stimulating factor alone, indicating that granulocytic differentiation is attenuated by addition of 1,25-dihydroxyvitamin D (3). Therefore, in contrast to our previous data, the present findings suggest that granulocyte colony-stimulating factor synergistically augments 1,25-dihydroxyvitamin D (3)-induced monocytic differentiation in our murine bone-marrow cell cultures. Considering previously published data, we also suggest that these synergistic effects may be mainly due to the combination of two distinct effects such as the primary proliferative effects of granulocyte colony-stimulating factor on multipotent stem cells and the subsequent differentiative effects of 1,25-dihydroxyvitamin D (3) on proliferating cells.

Animals↗
PubMed1979

Affinity labeling of the catalytic subunit of cyclic AMP-dependent protein kinase by N alpha-tosyl-L-lysine chloromethyl ketone.

The catalytic subunit of cyclic AMP-dependent protein kinase (from rabbit skeletal muscle; ATP:protein phosphotransferase, EC 2.7.1.37) was found to be irreversibly inactivated by chloromethyl ketone derivatives of lysine and phenylalanine, chemical reagents originally designed for labeling the active sites of the proteolytic enzymes trypsin and chymotrypsin. This inactivation was shown to occur at pH 7.5 and 22 degrees C, conditions under which chemically related alkylating reagents such as chloroacetamide and chloroacetic acid (which do not possess the amino acid side chain) fail to inactivate the enzyme. In the case of the chloromethyl ketone derivative of N alpha-tosyl-L-lysine, the enzyme could be protected by its nucleotide substrate (MgATP), by one of its protein substrates (histone H2b), and by its regulatory subunit which, upon binding, shields the active site of the catalytic subunit. Differential labeling experiments, together with kinetic studies of the rates of modification of the sulfhydryl groups in the enzyme before and after inactivation with the chloromethyl ketone, suggest that the loss of activity is associated with one (kinetically characterized) sulfhydryl group present either at the active site of the enzyme or at a site intimately associated with it. The general implications of these results regarding the interpretation of affinity labeling experiments carried out in complex mixtures of proteins or under in vivo conditions are discussed.

Affinity Labels↗
PubMed1999

Catalytic properties of selenophosphate synthetases: comparison of the selenocysteine-containing enzyme from Haemophilus influenzae with the corresponding cysteine-containing enzyme from Escherichia coli.

The selD gene from Haemophilus influenzae has been overexpressed in Escherichia coli. The expressed protein was purified to homogeneity in a four-step procedure and then carboxymethylated by reaction with chloroacetate. N-terminal sequencing by Edman degradation identified residue 16 as carboxymethyl selenocysteine, which corresponded to the essential cysteine residue in the glycine-rich sequence of the E. coli selenophosphate synthetase. It would be expected that an ionized selenol of a selenocysteine in place of a catalytically essential cysteine residue would result in an enzyme with increased catalytic activity. To test this hypothesis we kinetically characterized the selenocysteine containing selenophosphate synthetase from H. influenzae and compared its catalytic activity to that of the cysteine containing selenophosphate synthetase from E. coli. Our characterization revealed the Km values for the two substrates, selenide and ATP, were similar for both enzymes. However, the selenocysteine-containing enzyme did not exhibit the expected higher catalytic activity. Based on these results we suggest a role of selenocysteine in H. influenzae that is not catalytic.

Adenosine Triphosphate↗
PubMed1996

The kinetics, substrate, and inhibitor specificity of the monocarboxylate (lactate) transporter of rat liver cells determined using the fluorescent intracellular pH indicator, 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein.

The kinetics of transport of L-lactate, pyruvate, ketone bodies, and other monocarboxylates into isolated hepatocytes from starved rats were measured at 25 degrees C using the intracellular pH-sensitive dye, 2',7'-bis(carboxyethyl)- 5(6)-carboxyfluorescein, to detect the associated proton influx. Transport kinetics were similar, but not identical, to those determined using the same technique for the monocarboxylate transporter (MCT) of Ehrlich Lettré tumor cells (MCT1) (Carpenter, L., and Halestrap, A. P. (1994) Biochem. J. 304, 751-760). Km values for L-lactate (4.7 mM), D-lactate (27 mM), D,L-2-hydroxybutyrate (3.3 mM), L-3-hydroxybutyrate (12.7 mM), and acetoacetate (6.1 mM) were very similar in both cell types, whereas in hepatocytes the Km values were higher than MCT1 for pyruvate (1.3 mM, cf. 0.72 mM), D-3-hydroxybutyrate (24.7 mM, cf. 10.1 mM), D-2-chloropropionate (1.3 mM, cf. 0.8 mM), 4-hydroxybutyrate (18.1 mM, cf. 7.7 mM), and acetate (5.4 mM, cf. 3.7 mM). In contrast, the hepatocyte carrier had lower Km values than MCT1 for glycolate, chloroacetate, dichloroacetate, and 2-hydroxy-2-methylpropionate. Differences in stereoselectivity were also detected; both carriers showed a lower Km for L-lactate than D-lactate, while hepatocyte MCT exhibited a lower Km for D- than L-2-chloropropionate and for L- than D-3-hydroxybutyrate; this is not the case for MCT1. A range of inhibitors of MCT1, including alpha-cyanocinnamate derivatives, phloretin, and niflumic acid, inhibited hepatocyte MCT with K0.5 values significantly higher than for tumor cell MCT1, while stilbene disulfonate derivatives and p-chloromercuribenzene sulfonate had similar K0.5 values in both cell types. The branched chain ketoacids alpha-ketoisocaproate and alpha-ketoisovalerate were also potent inhibitors of hepatocyte MCT with K0.5 values of 270 and 340 microM, respectively. The activation energy of L-lactate transport into hepatocytes was 58 kJ mol-1, and measured rates of transport at 37 degrees C were considerably greater than those required for maximal rates of gluconeogenesis. The properties of the hepatocyte monocarboxylate transporter are consistent with the presence of a distinct isoform of MCT in liver cells as suggested by the cloning and sequencing of MCT2 from hamster liver (Garcia, C. K., Brown, M. S., Pathak, R. K., and Goldstein, J. L. (1995) J. Biol. Chem. 270, 1843-1849).

Animals↗
PubMed2003

Adult hypocellular acute leukaemia with lymphoid differentiation.

The rare hypocellular variants of acute leukemia (AL) previously also termed smouldering leukemia, almost always exhibit myeloid differentiation. Very rare cases of hypocellular AL with lymphoid differentiation have been reported, usually in children. This paper describes two cases (an 87-year-old woman and a 79-year-old man) in whom the blood findings were suggestive of AL. Paraffin-embedded bone marrow biopsy specimens revealed similar findings in both patients: there was severe hypocellularity, the cells of normal hemopoiesis were greatly reduced in number, and there was a diffuse increase in blast cells, which represented more than 50% of nucleated marrow cells. The blasts coexpressed TdT and CD34 and were negative for myeloperoxidase, CD117, CD68 and naphthol AS-D chloroacetate esterase. For the first time immunohistochemical Pax-5/CD34 doublestainings are provided, which revealed the blasts in one case to coexpress Pax-5 and CD34. All the blasts were CD79a-positive and 20% were also CD10-positive. In the other case, 20% of the blasts were CD79a-positive, 30% coexpressed Pax-5 and CD34 by doublestaining, and showed a clonal rearrangement of the immunoglobulin heavy chain gene. Thus a diagnosis of AL of lymphoid lineage, hypocellular variant, was made on the basis of immunohistochemical findings. The clinical course appears to be similar to that of hypocellular AML, as neither patient has developed overt leukemia during the one-year follow-up period.

Aged↗
PubMed2006

Microwave-assisted organic synthesis of 3-(D-Gluco-pentitol-1-yl)-1H-1,2,4-triazole.

The condensation of D-glucono- and D-galactono-1,5-lactone and thiocarbohydrazide to give 3-(D-alditol-1-yl)-4-amino-5-mercapto-1,2,4-triazoles 4 and 5 is accelerated by the use of microwave-assisted organic reaction (MAOS). The deamination and dethiolation of compound 4 to give 6 was also accelerated by the use of MAOS. Condensation of 4 and 5 with p-nitrobenzaldehyde afforded Schiff bases 8 and 9, respectively, within 4 min under microwave irradiation (MWI), whereas with ethyl chloroacetate the thioalkylated products 14 and 15 were obtained in 8 min. The structures of the synthesized compounds were confirmed by 1H NMR, 2D NMR, and mass spectra.

Microwaves↗
PubMed1995

Effects of ozone on the epithelial and inflammatory responses in the airways: role of tumor necrosis factor.

We have investigated the possibility that tumor necrosis factor alpha (TNF) plays a role in the increased airway permeability and an inflammatory response following an acute ozone (O3) exposure. Male Sprague-Dawley rats were injected, intraperitoneally, with either rabbit anti-mouse antibody to TNF (anti-TNF) or preimmune rabbit serum, 2 h before a 3-h exposure to O3 or purified air. Permeability, as determined by [99mTc] diethylenetriamine pentaacetate (DTPA) transport, total protein and albumin concentrations in the bronchoalveolar lavage (BAL), and the inflammatory cell response in the BAL were assessed 10 h after the exposure was completed. The O3-exposed group that was injected with anti-TNF showed a significant decrease in permeability to DTPA in comparison to the O3- exposed group injected with preimmune rabbit serum. There was no difference between the anti-TNF group and the purified air group. In contrast, the total protein and albumin levels in the BAL were significantly greater in both of the O3-exposed groups than in the purified air group. The concentrations of protein and albumin in the anti-TNF group did, however, show an attenuating trend when compared to the preimmune O3-exposed group. The polymorphonuclear leukocytes (PMNs) in BAL of the anti-TNF group also showed an attenuating trend when compared to the preimmune O3-exposed group, but both of these O3-exposed groups were significantly greater than the purified air group. Lung sections stained with naphthol AS-D chloroacetate esterase showed an increase in the number of stained PMNs in the anti-TNF group in comparison to the preimmune O3- and air-exposed groups. These data suggest that TNF plays a role in the increase in tracheal permeability as determined by DTPA transport, while the contributing role that TNF plays in bronchoalveolar permeability and the inflammatory response seen following an acute exposure to 0.8 ppm O3 is less evident.

Animals↗
PubMed1989

[Granulocytic sarcoma: apropos of 7 case reports].

Seven cases of granulocytic sarcoma (GS) with different clinical presentations are reported. Granulocytic sarcoma is diagnosed by tumor biopsy. The antilysozyme immunoperoxidase technique and the ASD chloroacetate esterase staining are used to confirm the diagnosis. The recent development of immunohistological staining, for demonstration of intra-cellular or surface antigens, is also useful to recognize GS. The prognostic significance of GS is discussed. For isolated GS, early aggressive treatment with chemotherapy and local radiotherapy is proposed.

Adult↗
PubMed1984

Eosinophilic differentiation of the human promyelocytic leukemia cell line, HL-60.

HL-60 promyelocytic leukemia cells differentiated to eosinophils and eosinophilic precursors when cultured under mildly alkaline conditions (pH 7.6-7.8) for 7 d without refeeding. New cytoplasmic granules appeared blue in the least mature cells and red in the most mature cells when stained with Wright-Giemsa. The granules also stained with Luxol-fast-blue, a characteristic of eosinophil granules. Furthermore, most cells contained the eosinophil major basic protein (MBP); the Charcot-Leyden Crystal (CLC) protein (lysophospholipase), eosinophil peroxidase, acid phosphatase, and arylsulfatase were also detected in a portion of these cells. The eosinophil major basic protein was found in a high proportion of undifferentiated cells, and thus may be constituitively produced. By examining finely banded chromosomes, translocation break points were demonstrated at q22 on one chromosome 16 and at q23 on the other homologue; abnormalities in this region of the long arm of 16 are a characteristic finding in the recently described syndrome of acute myelomonocytic leukemia (AMMoL) with abnormal bone marrow eosinophils. In common with the bone marrow eosinophils in these patients, the HL-60 eosinophil granules contained chloroacetate esterase and periodic-acid Schiff (PAS) reactive material; crystalloid inclusions were rare. Therefore, the HL-60 cell line appears to be an in vitro model for eosinophilopoiesis and may be specially suited for the study of the abnormal eosinophils seen in certain malignant conditions.

Blood Proteins↗
PubMed1994

Localized Leishmania lymphadenitis. Immunohistochemical studies.

Tissues from 10 patients with localized leishmania lymphadenitis were stained by immunoperoxidase technique for leishmanian antigens, immunoglobulins (Ig), complement, components, alpha 1-antitrypsin, and fibrin and by routine and chloroacetate esterase techniques. Lymph nodes with leishmania lymphadenitis showed a granulomatous process with a varying degree of necrosis, leishmanian amastigotes, abundant plasma cells, and focal fibrosis. Leishmanian antigens stained by rabbit anti-Leishmania tropica antiserum was detected in lymph nodes with granulomatous lymphadenitis (eight cases examined) and in a skin lesion but not in a lymph node showing only nonspecific hyperplasia. Positive antigen staining was seen in leishmanian amastigotes, granulomata, and (in three cases) vascular smooth muscles. Dominant plasma cell classes were IgG and IgE. Macrophages and granulomata stained positively for IgG and IgE (but not for IgM or IgA), faintly for C3, and strongly for alpha 1-antitrypsin. Mast cells were few. IgG and IgE may be involved in a specific way in this condition; formation of immune complexes with leishmanian antigens leads to immunologically mediated lysis of the host macrophages. This finding is important for the understanding of the pathogenesis of leishmania lymphadenitis and for effective elimination of the parasites.

Animals↗
PubMed1975

Immunologic and cytochemical properties of histiocytic and mixed histiocytic-lymphocytic lymphomas.

Lymph nodes were biopsied from seven patients with the presumptive clinical diagnosis of lymphoma and studied for their ability to form spontaneous rosettes with sheep erythrocytes (T cell marker), for surface immunoglobulins (B cell marker), for cytochemical reactivity with peroxidase, alpha-naphthyl acetate and butyrate esterases, naphthol ASD chloroacetate esterase, acid phosphatase, periodic acid-Schiff, Sudan black B, and Wright-Giemsa on touch preparations, as well as in hematoxylin and eosin-stained sections. Lymph nodes from patients without hematologic malignancy served as control. Diagnoses of diffuse histiocytic lymphoma were made in five cases and diffuse mixed histiocytic-lymphocytic lymphoma in 2 cases. The cytochemical staining of the lymphoma cells were typical of lymphoid cells rather than macrophages. In five cases neoplastic cells contained surface immunoglobulins, suggesting a B cell origin, and in one case a paucity of cell surface markers was found. Cells from uninvolved nodes of lymphoma patients could not be differentiated from those of the control group.

Animals↗
PubMed1977

Esterase reactions in acute myelomonocytic leukemia.

Specific and nonspecific esterase reactions of bone marrow cells from 14 patients with untreated acute myelomonocytic leukemia and six patients with acute histiomonocytic leukemia were examined. The technic for esterase determination permitted simultaneous visualization of both esterases on the same glass coverslip containing the marrow cells. In cases of acute histiomonocytic leukemia, monocytes, monocytoid hemohistioblasts and undifferentiated blasts stained intensely positive for nonspecific esterase, using alpha-naphthyl acetate as the substrate. No evidence of specific esterase activity using naphthol ASD-chloroacetate as the substrate and fast blue BBN as the dye coupler was apparent in these cells. In all of the cases of acute myelomonocytic leukemia, both specific and nonspecific esterases were visualized within monocytes, monocytoid cells, and granulocytic cells that had monocytoid-type nuclei. Nonspecific esterase activity was not observed in polymorphonuclear leukocytes in cases of myelomonocytic leukemia. The results support a current viewpoint that acute myelomonocytic leukemia may be a variant of acute myeloblastic leukemia, and that cytochemically, many of the leukemic cells in myelomonocytic leukemia share properties of both granulocytes and monocytes.

Acute Disease↗