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PubMed1997

Influence of hydroxypropyl beta-cyclodextrin on the stability of benzylpenicillin in chloroacetate buffer.

Hydroxypropyl beta-cyclodextrin (HP beta CyD) has been shown to stabilize a wide variety of chemically distinct pharmaceutical entities through inclusion-complex formation between drug and cyclodextrin. The effect of HP beta CyD on the acid-catalysed hydrolysis of benzylpenicillin (penicillin G) was evaluated in chloroacetate buffer at pH 2.20. At penicillin G: cyclodextrin molar concentration ratios from 1:1 to 1:10, HP beta CyD effected stabilization of penicillin G by 1.56- to 5.21-fold. At all temperatures, the observed first-order rate constant (kobs) values assumed a non-linear, Michaelis-Menten type decrease as a function of increasing HP beta CyD concentration. Degradation of penicillin G complexed with HP beta CyD (penicillin G-HP beta CyD), was approximately ninefold slower than uncomplexed penicillin G. The proportion of penicillin G degrading in either of these forms was, in turn, determined by the equilibrium constant for the complexation. The apparent thermodynamic and activation parameters for the complexation between penicillin G and HP beta CyD have also been evaluated. The negative standard enthalpy change (delta H degrees) for the complexation implied that the penicillin G-HP beta CyD complex would be predisposed towards enhanced stability, and thus the kobs value for the hydrolysis of penicillin G decreased with reduction of temperature in these systems. The lack of difference between the enthalpies of activation (delta H ++) for the hydrolysis of uncomplexed and complexed penicillin G seemed to be compensated by the significant difference between the entropies of activation (delta S ++) for these hydrolytic reactions. The results indicate that HP beta CyD represents a viable means of stabilization of penicillin G solutions at the pH employed in this study.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed1976

Pharmacological studies of N,N-dimethylaminoethyl chloroacetate and N,N-dimethylaminoethyl acrylate as inhibitors of choline acetyltransferase in isolated skeletal and smooth muscle preparations.

Two tertiary amine esters, N,N-dimethylaminoethyl chloroacetate (Cl-DMA) and N,N-dimethylaminoethyl acrylate (acryl-DMA), which have recently been shown to be inhibitors of choline acetyltransferase (ChAc) were investigated to determine their actions in isolated skeletal and smooth muscle preparations. Both compounds caused neuromuscular blockade in indirectly stimulated nerve-muscle preparations (ED50 values of Cl-DMA were 6.9 -42.0 X 10(-4) M and those of acryl-DMA were 1.2-5.8 X 10(-4) M). The blockade was completely or partially reversible after drug washout. A comparison of the ED50 values for neuromuscular blockade with the ID50 values for ChAc inhibition suggested that the acryl-DMA compound might not cause neuromuscular blockade via ChAc inhibition because the potency ratios (ED50/ID50) of Cl-DMA were higher than 1, whereas those of acryl-DMA were equal to or lower than 1. This was borne out by further experiments on isolated neuromuscular preparations which showed that the site of action for acryl-DMA was post-junctional, whereas that for Cl-DMA was prejunctional. In addition, the weak stimulating properties of Cl-DMA and acryl-DMA were investigated in isolated skeletal and smooth muscle. Cl-DMA was shown to be a partial cholinergic agonist, whereas acryl-DMA was a nonspecific stimulant not involving cholinergic receptors. Although both Cl-DMA and acryl-DMA are inhibitors of ChAc, only Cl-DMA appears to have sufficient specificity for use as a possible ChAc inhibitor in vivo.

Acetates↗
PubMed1986

Naphthol-AS-D-chloroacetate esterase activity in globule leucocytes in the tracheal epithelium of rats.

The enzyme naphthol-AS-D-chloroacetate esterase is histochemically demonstrated in the granules of globule leucocytes in the tracheal epithelium of rats. The enzyme reactivity may be used as a cytochemical marker of these cells. The previously postulated mast cell origin of globule leucocytes is doubted, and the possibility that globule leucocytes belong to the group of natural killer cells is discussed. The biological role of the located esterase and the function of the globule leucocytes are also briefly discussed.

Animals↗
PubMed1990

Multimarker immunohistochemical staining of calgranulins, chloroacetate esterase, and S100 for simultaneous demonstration of inflammatory cells on paraffin sections.

Mac387 monoclonal antibody (MAb) recognizes two calcium binding, myeloid-associated proteins, now termed calgranulins, expressed at high levels by neutrophils and monocytes. Calgranulins are related to migration inhibitory factor (MIF) and are lost in a few days from monocytes differentiated in vitro. This marker is therefore potentially useful to analyze macrophage heterogeneity and turnover in tissue sections. In this study, we developed an immunohistochemical multimarker technique, including calgranulin demonstration, suitable for analyzing different inflammatory cells on paraffin-embedded material. The technique was carried out in subsequent steps demonstrating (a) naphthol AS-D chloroacetate esterase (CAE); (b) S100 immunoreactivity using a rabbit antibody in peroxidase-antiperoxidase (PAP) staining; and (c) Mac387 immunoreactivity using the alkaline phosphatase-anti-alkaline phosphatase (APAAP) technique. CAE staining was introduced in this method to distinguish Mac387+/CAE- macrophages from Mac387+/CAE+ neutrophils, and Mac387-/CAE+ mast cells. S100 protein is strongly expressed within lymphoid tissues by dendritic accessory cells and was then applied to distinguish these cells from S100-macrophages. We have also verified the possibility of reducing the staining time for this time-consuming procedure by use of microwave irradiation. The technique was applied to a representative variety of normal and pathological samples to assess its usefulness for study of cell heterogeneity. Our results showed the multimarker technique to be highly informative in the study of inflammatory lesions (e.g., rheumatoid arthritis, sarcoid and cat-scratch granulomas, dermathopathic lymphadenopathy), and is of wide potential value as an aid to histopathological diagnosis of several diseases.

Antibodies, Monoclonal↗
PubMed2001

Acute promyelocytic leukemia, hypogranular variant, with uncharacteristic staining with chloroacetate esterase.

A diagnosis of the hypogranular variant of acute promyelocytic leukemia (APLv) may be difficult to establish based on cytomorphology alone. However, the great majority of cases have a classical immunophenotype by flow cytometric immunophenotyping (FCI) (CD13+, CD33+, dim CD64+, HLA-DR-, and CD34-) and a classical enzyme cytochemical (EC) staining pattern. [intensely staining with myeloperoxidase, Sudan Black B, and chloroacetate esterase (CAE) and negative with alpha'-naphthyl acetate and butyrate esterases]. Although the immunophenotype of APLv by FCI has varied in the literature (HLA-DR +/- and CD34 +/-), the EC staining pattern has remained constant. We report a case of APLv with characteristic cytomorphology, compatible FCI data (CD13+, CD33+, dim CD64+, HLA-DR +/-, and CD34-), chromosomal detection of t(15; 17), and molecular detection of the PML/RAR alpha fusion gene; however, staining of the leukemic cells with CAE was quite uncharacteristic. We describe our findings.

Aged↗
PubMed1985

Simultaneous demonstration of nonspecific esterase and chloroacetate esterase in human blood cells.

A new cytochemical method is described for the simultaneous demonstration of nonspecific esterase in monocytes and chloracetate esterase in granulocytes. The procedure uses both alpha-naphthyl butyrate and naphthol AS-D chloroacetate as substrates and hexazotized pararosaniline as the coupler. The enzyme reaction products are highly chromogenic and their localization is precise. This method is potentially useful for the accurate diagnosis of the acute monocytic leukemias. Its advantages and limitations are also discussed.

Acute Disease↗
PubMed1991

[Diagnostic use of neutrophil segments negative for peroxidase, chloroacetate esterase and sudanophilia in peripheral blood in leukemia].

The paper contains the results of three cytochemical reactions used for detection of myeloid differentiation (peroxidase, sudanophilia, chloroacetate esterase) in neutrophil segments of the peripheral blood stream in 107 patients with acute myeloid or lymphatic leukaemia. Enzymatically deficient segments were detected in 23 (34.8%) patients with acute myeloid leukaemia. They were not found in any patients lymphatic leukaemia not in healthy subjects. The concurrent deficit of all three reactions was found in 69% of the cases with defective neutrophil segments. However, also isolated affection of any of these reactions was found. In acute leukaemias, not differentiated from the cytochemical and immunophenotypical aspect, we may consider simple evidence of the presence of the mentioned abnormal neutrophil segments in peripheral blood as a highly probable sign of myeloid differentiation of acute leukaemia.

Acute Disease↗
PubMed1979

Re-evaluation of turbidimetry of proteins by use of aromatic sulfonic acids and chloroacetic acids.

From studies on 11 different proteins (including native albumin and albumin with reduced disulfide-bridges) treated with sulfosalicylic, 2-naphthalenesulfonic, toluenesulfonic, dichloroacetic, or trichloroacetic acids, we elucidate the interactions determining the resulting turbidities and other factors affecting turbidities, and we discuss the clinical utility of such turbidimetry. At least three interactions are important in determining turbidity: reduction of positive charges on the protein, hydrogen bonding of the non-ionized chloroacetic acids with the protein, and hydrophobic interaction of the aromatic sulfonic acids with albumin. Turbidity varies appreciably with the species of acid and protein, concentrations of acid, temperature, and standing time after acid is added. We conclude that this technique should be restricted to confirming proteinuria.

Albumins↗
PubMed1989

DNA-protein, DNA interstrand cross-links induced by camphoramine chloroacetic platinum in vitro.

Effects of camphoramine chloroacetic platinum (CCP) on DNA migration and transcription, DNA-protein and DNA interstrand cross-links induced by CCP were investigated by using agarose gel electrophoresis, alkaline elution and enzymatic techniques, respectively. Chromosome break down and migration alteration of DNa modified by CCP were observed. Plasmid pAR 436 DNA transcription was also blocked when the DNA was treated with CCP. The cross-links took place 8 h after HeLa cells were exposed to CCP 10 mumol/L and higher number of cross-links were obtained after treatment with the agent 20 mumol/L. The number of cross-links was also found to be decreased when the cell lysis was digested with proteinase K. These results suggest that CCP can also induce DNA-protein cross links. Enzymatic studies indicated that CCP preferentially attacks guanine in DNA and restriction enzymes are unable to cleave G-platinated at interval of one base to the restriction sequence.

Animals↗
PubMed1977

[Nonspecific esterase and naphthol-AS-D-chloroacetate esterase in monocytoid and myeloid cells of healthy cattle and cattle suffering from leukosis].

The reaction to non-specific esterase can be used for the identification of the monocytoid cells of the periphery. A negative reaction is exhibited by neutrophile and eosinophile leucocytes and erythrocytes. Varying results are obtained from lymphocytes, rendering it impossible to use this method in the group of lymphoid cells of the periphery or marrow. In the group of large marrow cells (promonocytes), non-specific esterase gave a very strong reaction; this applies both to the marrow of healthy cattle and cattle suffering from leucosis. For the time being, efforts to use this reaction for the solution of the problem of the differentiation of monocytoid cells and cells of similar size in the myeloid series of the bone marrow have not been successful. In neutrophile leucocytes of the periphery, naphtol-AS-D-chloroacetate esterase gives a less intensive reaction than in humans. For this reason, it is less suitable for the differentiation of these cells. Other cell types (eosinophile leucocytes, monocytes, lymphocytes, erythrocytes as well as their bone-marrow stages) give a negative reaction. In the group of large marrow cells of the myeloid series (promyelocytes and neutrophile myelocytes), naphtol-AS-D-chloracetate esterase shows a more intensive reaction in healthy cattle, as compared with cattle suffering from leucosis.

Animals↗
PubMed1982

The chloroacetate esterase reaction for mast cells in dermatopathology: a comparison with metachromatic staining methods.

This paper compares standard metachromatic methods with Leder's chloroacetate esterase reaction on mast cells in paraffin wax-embedded tissue of urticaria pigmentosa and a variety of inflammatory and benign neoplastic cutaneous conditions. Our conclusions are that Leder's method allows easier identification of mast cells and can be a useful adjunct to conventional metachromatic methods. The technique could be conveniently adopted in routine dermatopathology for mast cell identification.

Carboxylic Ester Hydrolases↗
PubMed1983

Naphthol AS-D chloroacetate esterase reaction. Systematic modifications for optimization to smears and sections.

Currently used methods for naphthol AS-D chloroacetate (NASDCA) esterase reactions can be divided into 3 groups according to the coupler used, i.e., fast garnet GBC, pararosanilin, and new fuchsin. These 3 groups were systematically modified with regard to modes of fixation and incubation in order to develop optimal methods for their application on sections of formalin-fixed and paraffin-embedded tissue as well as blood smears. After obtaining the optimal modifications for each of the 3 coupler methods, comparison was made between the 3 optimal methods for blood smears and the 3 for tissue sections. For blood smears, the methods using either fast garnet GBC or new fuchsin as coupler were found to be equally excellent, while the method using pararosanilin as coupler was not as superior. For tissue sections, the methods using either fast garnet GBC or pararosanilin were found to be equally excellent, while the method using new fuchsin was not as superior. Thus, only the method using fast garnet GBC as coupler was found excellent for both purposes. It was also found that bone marrow biopsies routinely processed through formalin-fixation would yield excellent NASDCA esterase reaction provided Plank and Rychlo's method instead of EDTA was employed for decalcification.

Biopsy↗
PubMed1978

[Use in histological technic of naphtol AS-D chloroacetate for demonstration of granulocyte series elements].

The authors report their experience of a histo-enzymatic method, using Naphtol AS-D Chloroacetate as a substrate, for the specific demonstration of elements of the granulocyte series, in histological sections, after formol fixation and mounting in paraffin wax. This simple and reliable staining technique offers the possibility of very rapid diagnostic orientation in haematological conditions.

Bone Marrow Cells↗