Effect of new quaternary bisammonium compounds on the growth and cell surface hydrophobicity of Enterobacter cloacae

The effect of new quaternary bisammonium salts (QBAS) of series A: 1, 10-[bis(alkyldimethyl-diammonium)]-4,7-dioxo-3,8-dioxoundecandi bromides and series B: alpha-omega[bis(dodecyldimethyl-diammonium)]-3,x-dioxo-4,y- dioxoalcandibromides on the growth and surface hydrophobicity of E. cloacae strain was studied. The compounds of series A possess changing side substituent and the inhibition of growth displayed evident dependence of effect on length of alkyl with optimum at C9-C11 (cut off effect). In series B are compounds with changing joining chain between two ammonium cations where the mentioned effect was not observed. The cell surface hydrophobicity of tested strain was determined by the method of adhesion to hydrocarbon--xylene (BATH) and in salt aggregation test of ammonium sulphate (SAT). The effect of 1/4 of the MIC compounds series A with nonyl, decyl and undecyl reduced the adhesion of E. cloacae cells below 50% against the control. These compounds at sub-MICs decreased salt-aggregative ability of E. cloacae cells. The influencing of cell surface hydrophobicity was not found after affecting of compounds at sub-MIC from series B with the exception of moderate decrease at compound with joining chain of C7. The length of chain connecting two symmetrical parts of molecule has slight impact on the effect of bisammonium salts. The influence of QBAS at sub-MICs on cell surface hydrophobicity can interfere with pathogenic potential of E. cloacae.     

New series of isoniazid hydrazones linked with electron-withdrawing substituents

A series of new isoniazid hydrazones was synthesized by two procedures. In the first isoniazid was activated with diethoxymethyl acetate and condensed with the appropriate anilines. Alternatively, substituted anilines were activated by diethoxymethyl acetate and subsequently condensed with isoniazid. NMR study confirmed that both synthetic approaches gave the same tautomer. All compounds were screened for in vitro antimycobacterial activity. Most of them exhibited the same activity against Mycobacterium tuberculosis (MIC 1 μmol L⁻¹) as isoniazid (INH), better activity against Mycobacterium kansasii 325/80 (MIC 0.125–0.250 μmol L⁻¹), high value of selectivity index (SI) and IC₅₀ between 0.0218 and 0.326 mmol L⁻¹. Compound 2o with the best SI was used as a model compound for the stability test and was found to be stable at neutral pH, but under acidic conditions it slowly hydrolysed.     

Nodular Fasciitis of the Oral Cavity with Partial Spontaneous Regression (Nodular Fasciitis)

Nodular fasciitis is a lesion found in the subcutaneous fascia that micoscopically presents as a benign proliferation of fibroblasts and myofibroblasts, which may be mistaken for a sarcoma due to clinically rapid growth. Diagnosis is by histopathology and of the immunohistochemical profile. We describe a case of nodular fasciitis in the oral cavity that demonstrated partial spontaneous regression. The patient was a 32-year-old man with a buccal mucosal mass, which had grown rapidly for 45 days. On microscopic examination, the lesion displayed a well-delineated but not encapsulated proliferation of spindle cells, with a nodular growth pattern. Immunohistochemical analysis showed positivity of the spindle cells for the antibodies against smooth muscle actin and muscle-specific actin (HHF-35). Treatment of such lesions typically involves complete conservative excision, but the lesion may regress eventually in the absence of definitive treatment.