It is generally accepted that strains of Staphylococcus aureus which are susceptible to penicillin G do not produce ,8-lactamase. However, we have found that such a strain susceptible to 0.06 ,ug of penicillin per ml and 0.56 lAg of methicillin per ml produces ,8-lactamase(s) which hydrolyzes penicillin G, methicillin, 6-aminopenicillanic acid, and probably cephaloridine.'The enzyme which is found only during very early log phase of the growth cycle is not inducible either by penicillin or methicillin and is cell bound and liberated only by disruption of the cell. The rate of enzymatic hydrolysis of methicillin was 60% that of benzylpenicillin. This finding suggests that the elaboration per se of ,B-lactamase does not necessarily afford resistance to penicillin in this gram-positive-producing cell.Previous reports (7,8,(10)(11)(12)(13) In Bacillus cereus, data have been presented (7,8) which are, at the very least, consistent with the hypothesis that 8-lactamase is involved in cell wall metabolism, probably during sporulation. In an inducible ,-lactamase-producing Staphylococcus aureus, a peptidoglycan has been isolated (10) from late lag and early logphase cells which is apparently the effector for the endogenous formation of the enzyme, endogenous being defined as the spontaneous appearance off,-lactamase in the absence of exogenously added inducer.The earliest work by Abraham (1) noted that the enzyme present only in bacteria probably was not related to penicillin. It was also found that some penicillinase-producing species of Bacillus were susceptible to penicillin and that in S. aureus there was no correlation between amounts of enzyme produced and level of resistance (11).There are reports (9) indicating that, in some instances, ,B-lactamases produced by gram-negative bacteria are not the determinants of resistance to ,8-lactam antibiotics in these organisms; e.g., Hamilton-Miller (3) reported that in E. coli the enzyme was not important in conferring resistance to benzylpenicillin and ampicillin.In laboratory strains of B. cereus susceptible to benzylpencillin, we have previously reported (8) the spontaneous appearance of 16-lactamase immediately prior to the onset of sporulation. In this communication, evidence will be presented showing the presence of the enzyme in a penicillin-susceptible S. aureus. The enzyme(s) hydrolyzes not only penicillin G, but also methicillin, 6-aminopenicillanic acid, and probably cephaloridine. MATERIALS AND METHODS Organisms
The increasing incidence of methicillin-resistant Staphylococcus aureus infections (MRSA) in ENT diseases is becoming a big clinical concern. Here two patients are described who developed MRSA infections presented with unusual post-FESS epistaxis and postmastoidectomy perichondrial abscess and failed treatment with broad spectrum intravenous antibiotics. Following treatment with oral linezolid combined with local mupirocin dressing both patients fully recovered.
In a β-lactamase-inducible strain of Staphylococcus aureus , the enzyme appears spontaneously in the absence of added inducer during lag and early log phases of growth and then declines rapidly to low levels. The endogenous inducer responsible for appearance of the enzyme has been isolated and purified and characterized as a peptidoglycan, containing muramic acid, glucosamine, glutamic acid, alanine, lysine, and glycine. The inducing compound could be isolated from the cells only during the lag and early log phases and from no other later periods. The data obtained are consistent with the thesis advanced earlier from this laboratory that β-lactamase serves a cellular function in the producing cell more important and beyond its capability of hydrolyzing certain penicillins to the antibiotically inactive penicilloic acids.
Corrosive pharyngeal strictures without significant damage to esophagus and stomach were rarely reported. Here we report a case of corrosive acid poisoning with laryngopharyngeal strictures suffering for 39 years with difficulty in breathing, swallowing, phonation and sleep for whom endoscopic coblation assisted stricture adhesiolysis was done which was the first of its kind to our knowledge. As early as 5th postoperative day tracheostomy was decannulated, and the patient was able to swallow soft solids without maneuvers, liquids without nasal regurgitation, breathing via naturalis, phonating with normal neck position and a good sleep with no recurrences in 12 months follow up.
Attention Deficit Hyperactivity Disorder (ADHD) is the most common behavior disorder in children characterized by attention deficit, overactivity and impulsivity, which may persist into adolescence and adulthood. It is often complicated with multiple comorbid disorders which when undiagnosed or untreated significantly affects the children on aspects like academic skills, peer relationship, social life and difficulty in leading productive lives. This report presents a case of 12 year old male child with attention deficit and poor academic performance, diagnosed and treated for ADHD with a complex array of coexisting disorders untreated. An attempt is made to highlight the differential diagnosis for attention deficit in children, comorbid disorders, and the necessity for a multiprofessional approach in complete evaluation and comprehensive management of the same.
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