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Synthesis of bromoindolyl 4,7-di-O-methyl-Neu5Ac: specificity toward influenza A and B viruses.

N-Acetylneuraminic acid (Neu5Ac) was converted into the methyl ester methyl ketoside-8,9-epoxy derivative (8). Methylation of 8 followed by deprotection gave 4,7-di-O-methyl-Neu5Ac (10). Compound 10 was converted into the corresponding methyl ester-chloroacetate derivative, which was subsequently coupled to 5-bromo-indol-3-ol to give the chromogenic product (13). Deprotection of 13 gave 5-bromo-indol-3-yl 4,7-di-O-methyl-Neu5Ac (5). The product 5 was specifically cleaved by sialidase from either influenza A or influenza B virus to give an indigo-blue precipitate, but was not cleaved by several bacterial or viral sialidases tested. The properties of product 5 relative to a fluorescent substrate for sialidase were also documented.

Arthrobacter↗

Synthesis and preliminary characterisation of charged derivatives and hydrogels from scleroglucan.

The synthesis of negatively and positively charged polyelectrolytes from scleroglucan is described. Polycarboxylates were synthesised through nucleophilic substitution with chloroacetic acid or through a selective 2,2,6,6-tetramethyl-l-piperidinyloxy (TEMPO)-mediated oxidation of the primary alcohol groups. Amine groups were introduced through nucleophilic substitution with 2-chloroethylamine or 3-chloropropylamine. Reaction conditions were varied to obtain insight into the influence of variables on the degree of substitution. The conformational behaviour of the obtained polyelectrolytes was studied as a function of pH, temperature and solvent. For the products with a low degree of modification, evidence of an ordered conformation was found, whereas the polymers with a higher degree of modification behaved as random coils in solution. The negatively charged polymers were reticulated using the Ugi four-component condensation, obtaining negatively charged hydrogels. The positively charged polymers were reticulated using diethyl squarate (3,4-diethoxy-3-cyclobutene-1,2-dion, DES) to obtain positively charged hydrogels.

Absorption↗

Synthesis and antifungal activity of novel pyrano[2',3':4,5]thiazolo[2,3-b]quinazolines, pyrido[2',3':4,5]thiazolo[2,3-b]quinazolines and pyrazolo[2',3':4,5]thiazolo[2,3-b]quinazolines.

The starting materials thiazolo[2,3-b]quinazolines (5a,b) were obtained in one pot synthesis by treating octahydroquinazoline (2) with chloroacetic acid and aromatic aldehydes. Thiazoloquinazoline (5) was reacted with CH2(CN)2/piperidine and CH2(CN)2/NaOH (CH3OH), to furnish pyrano[2',3':4,5]thiazolo[2,3-b]quinazolines (6a,b) and pyrido[2',3':4,5]thiazolo[2,3-b]quinazoline (7), respectively. Refluxing of 5a with NH2CSNH2/KOH and hydrazines in ethanol furnished the corresponding, [1,3]thiazino[4'5':4,5]thiazolo[2,3-b]quinazoline (10) and pyrazolo[3',4':4,5]thiazolo[2,3-b]quinazolines (11a,b), respectively. Antifungal activity was shown for some of the synthesized compounds.

Antifungal Agents↗

Synthesis and anti-inflammatory activities of some thiazolo[3,2-a]pyrimidine derivatives.

Sixteen new 2-benzylidene-7-methyl-3-oxo-5-(substituted phenyl)-2, 3-dihydro-5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid methyl esters (1a-4d) have been synthesized by reacting 1,2,3,4-tetrahydropyrimidine-2-thiones (1-4) with chloroacetic acid and appropriate benzaldehydes in a single step. Their structures have been proved by IR, 1H NMR, mass spectra and elemental analysis. The compounds were tested for their anti-inflammatory activities. Test results revealed that compounds 1b, 1c, 4a and 4c exerted moderate anti-inflammatory activity at the 100 mg/kg dose level compared with indomethacin.

Animals↗

Supercritical fluid extraction and chromatography of cholesterol in food samples.

A method based on supercritical fluid chromatography is presented which can be used for the determination of cholesterol in certain foods. The method involves the extraction with supercritical carbon dioxide and analysis of the extracts using a capillary column with supercritical carbon dioxide as mobile phase and flame ionization detection. Quantification is achieved using cholesteryl chloroacetate as an internal standard.

Carbon Dioxide↗

Acute myeloblastic leukaemia in a cow.

A myeloblastic leukaemia was found in a 6-year-old Holstein cow. Although macroscopical lesions were not found in parenchymal organs, the animal had many neoplastic cells in the peripheral blood, bone marrow, lymph nodes, and spleen. By light microscopy most neoplastic cells appeared to be agranular blast cells, but some cells contained acidophilic granules and stained positively for naphthol AS-D chloroacetate esterase and lysozyme. Ultrastructural examination revealed that many of the blast cells had a few peroxidase-positive granules and corresponded to early promyelocytes.

Animals↗

Myelodysplastic syndrome: diagnostic implications of cytochemical and immunocytochemical studies.

Cytochemical and immunocytochemical studies were performed on bone marrow aspirates from 96 cases of primary myelodysplastic syndrome (MDS), 11 cases of secondary MDS, 22 cases of non-MDS hematologic disorders, and 10 cases of nondiagnostic, apparently normal marrow specimens to determine the practicality and utility of these stains for diagnosing MDS. Cytochemical studies included iron stain, periodic acid-Schiff (PAS), peroxidase, butyrate esterase, chloroacetate esterase, and double esterase stains. Immunocytochemical staining was done with monoclonal antibody HP1-1D, which recognizes the glycoprotein IIb/IIIa complex in megakaryocytes. The iron stain remained most helpful in identifying abnormal ringed sideroblasts, a feature of dyserythropoiesis, and thus in supporting the diagnosis of MDS. The PAS stain was helpful, if positive, in identifying patients with MDS; however, when it was negative, this stain did not help distinguish MDS from non-MDS hematologic disorders. The immunocytochemical stain with HP1-1D monoclonal antibody was also helpful in identifying atypical micromegakaryocytes, indicative of dysmegakaryopoiesis. Other cytochemical abnormalities were infrequently observed and were less specific for the diagnosis of MDS. The combination of two stains--for example, PAS and iron stain or PAS and double esterase--was helpful, however, in excluding MDS, inasmuch as neither the miscellaneous nor the control group stained positively with these combinations.

Bone Marrow↗

Cytochemical characterization of leukemic cells with numerous cytoplasmic granules.

Ten cases in which leukemic cells contained numerous cytoplasmic granules were examined by using a panel of cytochemical reactions. The diagnoses in the 10 cases were mast cell leukemia, chronic basophilic leukemia, and acute myeloid leukemia with basophilic differentiation in one case each, acute promyelocytic leukemia in two cases, acute megakaryoblastic leukemia in two cases, and blastic hairy cell leukemia in three cases. The cytochemical panel consisted of peroxidase, toluidine blue, chloroacetate esterase, aminocaproate esterase, tartrate-resistant acid phosphatase, and immunoalkaline phosphatase for platelet/megakaryocyte-specific antigen. The unusual cytologic features of leukemic cells in cases similar to our 10 cases have caused considerable diagnostic difficulties. In our 10 cases, however, the effective use of cytochemical studies helped to achieve accurate identification of the various types of leukemic cells. We conclude that the intelligent application of cytochemical techniques continues to be useful for the accurate cytodiagnosis of hematopoietic neoplasms.

Adult↗

Acute myelomonocytic leukemia: an unusual variant with both granulocytic and monocytic esterases in the leukemic cells.

By using the combination of alpha-naphthyl butyrate esterase and chloroacetate esterase for cytochemical detection of monocytes and granulocytes, respectively, we examined and identified five adult patients with acute myeloid leukemia whose leukemic cells often (20 to 30%) had the characteristics of both monocytes and granulocytes. All five patients were men, 23 to 82 years of age. Two patients had manifestations of preleukemia. One of these two patients had received treatment for lymphoma for 12 months before acute myelomonocytic leukemia was diagnosed. One patient had gum hypertrophy, and two had leukemia cutis. At the time of initial examination, four patients had blood leukocyte counts higher than 80,000/mm3 and one had leukopenia. Four patients received chemotherapy; three responded temporarily but died within 1 year after the myelomonocytic leukemia had been diagnosed. The patient with leukopenia has remained in complete remission for 2 years. With more frequent use of double esterase stains for classification of acute myeloid leukemias, this variant of acute myelomonocytic leukemia should be detected more often and its clinical behavior should be better understood.

Adult↗

Nonlymphoid hematopoietic malignant disease of the lymph nodes.

The extension of myeloproliferative malignant tumors to lymph nodes was studied in seven excision biopsies and 27 autopsies in which lymph nodes were obtained from all nodal regions. We observed the proliferation of poorly, partially, and well differentiated neoplastic cells with a predominance of immature cells of the granulocytic series and fewer cells of the erythroid and megakaryocytic cells lines. Disturbances of the lymph node architecture consisted of invasion by abnormal cells of the trabecular stroma, disrupting the reticulin mesh and extending toward the pericapsular area. In the lymph node a loose network of thin and thick fibers replaced the original framework. Generalized lymph node involvement at autopsy showed preservation of the architecture, both in cases with total replacement of the lymphoid population by abnormal cells and in cases with involvement by single cells or small groups of cells. Partial involvement occurred chiefly in the medullary zone, probably the result of hematogenous dissemination from the vascular plexus in medullary cords. Further abnormal cell development was linked to trabecular infiltration. The extensive involvement seen at autopsy took place by lymphatic dissemination. In lymph nodes studied at autopsy an abnormal immunoblastic reaction was observed. At first these abnormal cells were suspected of representing the myeloproliferative malignant disease, but the application of special staining techniques revealed their polyclonal cytoplasmic immunoglobulins. The chloroacetate esterase stain and the immunohistochemical stains for muramidase and hemoglobulin were especially useful in demonstrating that myeloproliferative diseases develop in the environment found in lymph nodes.

Adult↗

Erythroleukemic infiltration of a lymph node: use of hemoglobin immunohistochemical techniques in diagnosis.

Isolated submandibular adenopathy developed in a patient who had subacute erythroleukemia. Lymph node biopsy revealed a proliferation of immature cells and scattered foci of dyserythropoietic normoblasts. Since a review of the literature revealed no detailed description of an erythroleukemic lymph node infiltrate, a histopathologic study of this node was undertaken. The immature cells were identified as erythroblasts and pronormoblasts by histochemical staining (periodic acid-Schiff reagent and chloroacetate esterase), immunohistochemical reaction (directed against hemoglobin), and electron microscopy. The diagnosis of erythroleukemic lymph node infiltrate may be missed in the absence of a high index of suspicion. It is concluded that the detection of hemoglobin within malignant cells is most helpful in establishing the diagnosis.

Bone Marrow↗

The in vitro differentiation of mouse embryonic stem cells into neutrophils.

A reliable and effective in vitro differentiation system is described for the production of functional neutrophils from mouse embryonic stem (ES) cells. A three-step culture method was developed that enables abundant production and effective harvesting of mature neutrophils at high purity without sorting. Utilization of the OP9 stromal cell line, which does not produce macrophage colony stimulating factor (M-CSF) was found to enhance the number, percentage and duration of neutrophils produced. Based on a number of criteria, morphologically and functionally mature neutrophils can be produced using this method in approximately 16 days. This differentiation system provides a useful model system for studying neutrophil development and maturation in vitro and the many factors that regulate this process. Morphologically mature ES-derived neutrophils can be grown in culture that produce superoxide, flux calcium and directionally respond to the chemoattractant MIP-2. In addition, they express the granulocyte markers Gr-1 and the neutrophil specific antigen, as well as specific chloroacetate esterase. Interestingly, during their development in culture, regional areas of apparent neutrophil production can be identified that recapitulate certain aspects of the marrow environment. As ES cells can be genetically modified, this system enables evaluation of the effects of specific genetic alterations on neutrophil differentiation and function.

Animals↗

Biochemical characterization of a haloalcohol dehalogenase from Arthrobacter erithii H10a.

Arthrobacter erithii H10a possesses two enzymes capable of catalyzing the dehalogenation of vicinal halohydrins which have been designated as dehalogenases DehA and DehC. The DehA dehalogenase demonstrated greater activity toward 1,3-dichloro-2-propanol (1,3-DCP) while the DehC dehalogenase showed higher activity toward 3-chloro-1,2-propanediol (3-CPD) and brominated alcohols. The DehA dehalogenase was composed of two non-identical subunits (relative molecular mass of 31.5 and 34 kDa) which probably associate with other proteins to form a large catalytically active protein of 200 kDa. The two subunits were purified and the amino acid sequence of their tryptic digests determined. The DehA enzyme catalyzed the conversion of vicinal halohydrins to epoxides and the reverse reaction in the presence of an excess of halogen. This enzyme had maximum activity at 50 degrees C and a broad pH optimum over the range 8.5-10.5. The apparent K(m) and Vmax values for dehalogenation of 1,3-DCP and 3-CPD were 0.105 mM and 223 mumol min-1 mg-1; and 2.366 mM and 1.742 mumol min-1 mg-1, respectively. The enzyme was inhibited by 2-chloroacetic acid (MCA) and 2,2-dichloroacetic acid (DCA). The inhibition pattern suggested a mixed type inhibition which was predominantly uncompetitive. Amino acid modification experiments demonstrated that one or more cysteine and arginine residues are likely to be involved in catalysis or play an important role in the maintenance of the enzyme structure. The characteristics of the DehA enzyme are compared to those of previously reported haloalcohol dehalogenases and discussed in terms of diversity of this type of dehalogenase.

Alcohols↗

Cell viability and inflammatory response in hydrogel sponges implanted in the rabbit cornea.

In the quest for the development of a functional keratoprosthesis, the biocompatibility of the porous skirt material in the Chirila keratoprosthesis (KPro) was investigated. The population of live and dead cells within, and the inflammatory response to, a tissue-integrating poly(2-hydroxyethyl methacrylate) (PHEMA) sponge were studied. Samples of the hydrogel sponge were implanted in rabbit corneas and explanted at predetermined time points up to 12 weeks. The explanted sponges were subjected to cell viability assay using two types of fluoroprobes, 5-chloromethylfluorescein diacetate and ethidium homodimer-1. A semiquantitative analysis was performed to assess the number of dead cells within the sponge and in the area of corneal stroma proximal to the sponge. Five rabbits were used for each end point (2, 4 and 12 weeks). To investigate the inflammatory response to the sponge, immunocytochemistry, using specific antibodies to rabbit macrophages, enzyme histochemistry of chloroacetate esterase (to detect neutrophils) and transmission electron microscopy (TEM) were also employed at 24 h, 2, 4 and 12 weeks after implantation. Four weeks after implantation, fewer viable cells were observed in the sponge when compared to the 2-week implant. However, the proportion of viable cells increased dramatically by 12 weeks. The proportion of nonviable cells decreased gradually with time; central sponge contained 34+/-11 % dead cells after 2 weeks, and 15+/-4.3% after 12 weeks. The staining of inflammatory cells demonstrated the presence of macrophages and neutrophils up to 12 weeks after implantation. TEM confirmed the presence of these cell types and others. including eosinophils and myofibroblasts, as well as blood capillaries. The presence of a significant number of viable cells at each time point and the uniform reduction of the nonviable cell proportion with time suggests that the sponge is a conducive environment supporting a prolific, viable cellular colonization. Dead cells observed in the first instance indicate a normal injury pattern. However, the presence of a small but significant proportion of invading inflammatory cells 12 weeks after implantation confirms a characteristic pattern of wound healing within the sponges.

Animals↗

Aleukemic granulocytic sarcoma with AML1/ETO fusion gene expression and clonal T cell populations.

We report a unique case of aleukemic granulocytic sarcoma of the neck, originally misdiagnosed as non-Hodgkin's lymphoma (NHL), though chloroma was also suspected due to a greenish macroscopic appearance and the presence of myeloid chloroacetate esterase (CAE)+ cells. The proof of clonal T cell receptor gamma chain (TcRgamma) gene rearrangements in the recurring tumor was deemed to confirm the initial diagnosis of T cell NHL. Altogether five distinct types of clonal TcRgamma gene rearrangements were found in the tumor, bone marrow and peripheral blood. Only retrospectively, using RT-PCR, did we detect the acute myeloid leukemia subset-specific fusion gene AML1/ETO in the frozen samples of the relapsed tumor, as well as in the otherwise unaffected bone marrow and peripheral blood (representing 'minimal initial disease' in the latter two samples). Simultaneous staining verified that the neoplastic CAE+ cells and CD45RO+ T cells were different populations.

Adult↗

Effects of transfection of p210bcr-abl and bcr-v-abl into the factor-dependent human leukemia cell line HSM-911.

In order to clarify the action of the bcr-abl, a growth factor dependent human leukemic cell line (HSM-911) was transfected with p210bcr-abl or bcr-v-abl by electroporation. The cells transfected with bcr-v-abl, but not the cells transfected with p210bcr-abl, became growth factor independent. Some clones of the cells transfected with p210bcr-abl demonstrated cellular maturation (nuclear segmentation, becoming positive for naphthol ASD chloroacetate esterase, the disappearance of CD34 expression and the appearance of glycophorin A and CD10 expression). Moreover, these clones transfected with p210bcr-abl demonstrated apoptosis (increased expression of Fas and DNA ladder formation suggesting apoptotic DNA fragmentation). These findings demonstrated the different actions of p210 bcr-abl and bcr-v-abl, the former of which gave the cells the characteristics of maturation like the cells from chronic myelogenous leukemia, and the latter of which rendered the cells grow autonomously.

Apoptosis↗

Evidence for selenocysteine in ovine tissue organelles.

Subcellular fractions were prepared by differential centrifugation from heart and liver of a lamb labeled with 75Se-selenite. Crude fractions of nuclei, mitochondria, and microsomes from both tissues were solubilized with sodium dodecyl sulfate and chromatographed on columns of sephacryl S-200. A low molecular weight (MW) 75Se labeled cardiac cytosol protein (approximately 10,000 daltons) was partially purified by gel filtration chromatography. The major 75Se peaks from the sephacryl columns and the low MW cardiac protein were hydrolyzed in HCl under an inert atmosphere. When chromatographed on an amino acid analysis column, 75Se from each hydrolysate chromatographed in the identical position of 2,7-diamino-4-thia-5-selenaoctanedioic acid, the mixed oxidized dimer of cysteine and selenocysteine. The low MW cardiac protein was reacted with chloroacetate after reduction with borohydride. 75Se from a hydrolysate of this derivatized protein eluted in the same position as Se-carboxymethylselenocysteine on the amino acid analysis column. Thus, selenocysteine appears to be the predominant form of selenium in ovine heart and liver.

Animals↗

Comparisons on chemically-induced mutagenicity among four bacterial strains, Salmonella typhimurium TA102 and TA2638, and Escherichia coli WP2/pKM101 and WP2 uvrA/pKM101: collaborative study I.

A collaborative study of chemically-induced mutagenicity was performed using the four bacterial strains Salmonella typhimurium TA102 and TA2638 and Escherichia coli WP2/pKM101 and WP2 uvrA/pKM101 in order to compare the specific spectrum of response to chemicals among the four strains and to determine the usefulness (sensitivity) of each strain. Twenty laboratories participated in this study. As the first step, 29 compounds were tested for mutagenicity using the plate incorporation method with or without metabolic activation. The compounds consisted of 12 chemicals judged previously positive only in E. coli WP2 uvrA/pKM101, 15 of their derivatives, and the 2 well-known mutagens hydrazine and formaldehyde. The strains and the chemicals were sent from a central source to each laboratory. The tests were performed in two laboratories per chemical. Concerning the result with each strain, the number of chemicals which showed mutagenic activity were 10, 7, 9 and 17 in TA102, TA2638, WP2/pKM101 and WP2 uvrA/pKM101, respectively. Among these 29 compounds tested, no qualitative difference in the response to chemicals among the four strains was observed with 17 compounds, being 12 negative chemicals and 5 positive chemicals. The remaining 12 compounds showed varying results among the four strains. On the comparison of TA102 and WP2 uvrA/pKM101, the same qualitative response to chemicals was observed with 22 compounds. Thus, although compounds tested in this study were selected, partly based on a previously-judged positive response only in E. coli WP2 uvrA/pKM101, 76% of test chemicals showed the same sensitivity in TA102, 7 chemicals (24%) were only positive in the E. coli strains. Of these 7 chemicals, 5 were the acrylic acid ester derivatives and the chloroacetic acid ester derivatives possessing a common structure of a functional group esterized between acid and alcohol with two or more carbon radicals.

Escherichia coli↗