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Monoclonal antibodies (MAbs) have been useful for immunoscintigraphic applications in clinical diagnosis since they were introduced in nuclear medicine practice. The MAb ior egf/r3 developed at the Center of Molecular Immunology (Havana, Cuba) is a murine antibody that recognizes the human epidermal growth factor receptor (EGF-R) and has been used widely in the radioimmunodiagnosis of tumors of epithelial origin. Based on the direct Schwarz method, the present report describes the preparation of a freeze-dried formulation for radiolabeling the MAb ior egf/r3 with 99mTc for immunoscintigraphic applications. Radiolabeling efficiency, effects on immunoreactivity, biodistribution, pharmacokinetic, and stability of the formulation are reported. The study demonstrated that the freeze-dried formulation can be labeled with 99mTc at high yield. The resulting 99mTc-labeled ior egf/r3 MAb can be used to visualize in vivo human tumors of epithelial origin by immunoscintigraphy studies. The kit does not need any other addition or purification at the time of tagging other than the requisite amount of pertechnetate (40-50 mCi). Because the contents of the kit are lyophilized, no special storage or transportation is required.

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Monoclonal antibodies (MAbs) are being widely used for imaging studies, coupled mainly with 99mTc. The antibody ior egf/r3 is a MAb against human epidermal growth factor receptor (hEGF-r), and we have developed a method for optimum labeling of this MAb with 99mTc. The reduction was performed with 2-mercaptoethanol (2-ME) at a molar ratio of 2000:1 (2-ME:MAb) and methylene diphosphonate as transchelant. The integrity of reduced MAb was checked by mean of native polyacrylamide gel electrophoresis (PAGE) and gel filtration chromatography on Superose 12 (purity >99%). Radio colloids remained lower than 2%, and the labeling efficiency was 98.5%. The number of sulfhydryl groups generated was quantified using Ellman's reagent and was found to be 6.65+/-0.69 per antibody molecule. In vitro stability studies in several challenging conditions (DTPA, human serum albumin and human serum) were performed, and no significant loss in binding percentage was seen. Radio receptor assay was used to test immunoreactivity of the reduced MAb. Both labeled and unlabeled MAbs were able to compete for binding to the hEGF-r with radioiodinated EGF. Biodistribution studies in BALB/c mice are reported.

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Intravenous ciprofloxacin (200 mg every 12 hours) was compared with intravenous ceftazidime (1 g every eight hours) as therapy for 62 episodes of severe infections occurring in 60 adult patients, all of whom failed previous antimicrobial therapy. The study was designed as a prospective, controlled, randomized, non-blinded trial in a tertiary university care center. A variety of infections including skin and skin structure, urinary tract, bacteremia, pneumonia, and intra-abdominal infections were treated. Clinical cure was achieved in 83.3 percent (25 of 30) of patients treated with ciprofloxacin and in 87 percent (26 of 30) of patients treated with ceftazidime (p = 0.4). Bacteriologic and overall responses were also similar in both treatment groups (p = 0.4 and 0.375, respectively). Intravenous ciprofloxacin administered twice daily is an effective treatment for severe infections caused by susceptible organisms.

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Local sequelae of group A beta-hemolytic streptococci (GABHS) are common and can vary from otitis media, sinusitis, cervical adenitis associated with generalized adenopathy, peritonsillitis and persisting symptoms in spite of therapy, GABHS is one of the pathogens isolated in acute or chronic otitis media and in acute maxillary sinusitis. In cervical adenitis associated with generalized adenopathy GABHS is, along with S. aureus, the most commonly recovered bacteria. In peritonsillitis, GABHS can be recovered alone or in combination with anaerobes in 50% of the cases. These sequelae are usually associated with a slow clinical response to therapy and a high percentage of relapses, reinfections, and chronic infections in the presence of a penicillin-sensitive GABHS. One of the possible causes of these so-called failures is the interference that beta-lactamase producing bacteria can have on the activity of penicillin and similar compounds. When to select a beta-lactamase-resistant antibiotic for the treatment of an apparent penicillin-sensitive infection remains an important area for further research.

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El acido pseudomonico es un nuevo antibiotico derivado de la Pseudomonas fluorescens (NCIB 10586). Inhibe la sintesis proteica de los microorganismos sensibles y tiene actividad contra bacterias grampositivas, en especial S. aureus asi como contra algunas gramnegativas.Se estudiaron 50 pacientes con infecciones cutaneas, de los cuales 25 fueron tratados con acido pseudomonico y 25 recibieron placebo. Ambos grupos fueron similares por lo que respecta al tipo de infeccion y enfermidades asociadas. Se tomaron cultivos de superficie antes durante y despues del tratamiento. El medicamento activo y el placebo inerte se aplicaron en forma de crema 3 veces al dia durante 5 a 10 dias. Se trataron 22 infecciones secundarias y 3 primarias en cada uno de los dos grupos. Vientitres de los que recibieron acido pseudomonico se curaron, en comparacion con 16 del grupo testigo. Hubo una falla terapeutica en el grupo tratado con acido pseudomonico y 8 en el testigo. Por lo tanto, se puede concluir que algunas infecciones cutaneas pueden beneficiarse con el tratamiento topico de acido pseudomonico

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