The Ethics of Caring for Conjoined Twins The Lakeberg Twins

In June 1993, conjoined twins Amy and Angela Lakeberg became the focus of national attention. They shared a complex six-chambered heart and one liver; only one could survive separation surgery, and even her chances were slim. The medical challenge was great and the ethical challenges were even greater.     

Oral muscosal melanomas: The WESTOP Banff workshop proceedings

A workshop to discuss primary oral melanomas was convened at the annual Western Society of Teachers of Oral Pathology meeting in Bannf, Alberta, Canada. Fifty oral melanomas, identified from the files of the participants, were reviewed in order to better understand the clinical features, histologic spectrum, and natural history of these perplexing lesions. Results confirmed that oral melanomas occur in adults almost three times more frequently in men than women and have a decided predilection for the palate and gingiva. Some lesions exhibit a clinically detectable and prolonged in situ growth phase, whereas others seem to lack this property and exhibit only or predominantly invasive characteristics. Recurrences, metastases, and death from tumor were characteristic of the follow-up of a limited number of patients. Until definitive prospective data are collected that elucidate natural history, oral mucosal melanomas should be tracked separately from cutaneous lesions. All oral pigmented lesions that are not clinically diagnostic should be biopsied. Lesions with equivocal histopathologic features might be referred to as “atypical melanocytic proliferation” and should be excised. Recognition of lesions in an early in situ phase and aggressive treatment should have a favorable effect on prognosis. To enhance future or prospective study of these rare neoplasms, guidelines for reporting oral melanomas are suggested.     

Spontaneous resolution of a central vascular lesion of the mandible following needle aspiration

A case of a central vascular lesion of the mandible that appeared to be healing spontaneously after needle aspiration has been described. It is suggested that more lesions of this type than previously realized may have the potential to resolve spontaneously after simple needle aspiration, which leads to intramedullary hemorrhage, organization of a clot, and complete healing.     

A simple Escherichia coli system for monitoring HIV protease activity: analysis of two temperature-sensitive protease mutants

A simple Escherichia coli system has been developed for the detection of human immunodeficiency virus (HIV) protease activity. In this system, the protease sequence is placed downstream of the HIV gag polypeptide in an operon arrangement. Upon expression of the operon, gag serves as the substrate for the protease; the level of protease activity can be determined by measurement of the cleavage product of gag in cell extracts by Western immunoblotting. This system is useful in both detection of protease mutations generated by mutagenesis and in testing substrate specificity of the protease by mutagenesis of the gag sequence. Using this system, we have observed that modification of the N-terminus of HIV protease renders the enzyme temperature sensitive; the temperature sensitivity is made more pronounced by the conserved change of valine to isoleucine at residue eleven.     

A Two Step Purification of Recombinant Human Interleukin-1β Expressed in E. Coli

Recombinant human interleukin-1β has been expressed in high yield using E. coli with a cDNA clone obtained from SKhep1RNA. The rIL-1β is purified to apparent homogeneity using freeze-thaw extractions followed by hydrophobic interaction chromatography over phenyl Sepharose. The procedure can provide pure rIL-1β (up to 15 mg per liter of E. coli culture) without the use of denaturants and if desired, in the absence of column chromatographic steps. Purity is defined by the presence of a single band on 1-D polyacrylamide gels and a single spot on 2-D polyacrylamide gels. The purified protein exhibits a biological activity of 1 × 10⁷ units/mg in a fibroblast proliferation assay and is shown to cross-react with rabbit anti-human IL-1β sera.     

Plasmid-Related Transmissibility and Multiple Drug Resistance in Streptococcus faecalis subsp. zymogenes Strain DS16

Streptococcus faecalis subsp. zymogenes strain DS16 was found to harbor two plasmids, designated pAD1 (35 megadaltons) and pAD2 (15 megadaltons). pAD1 is transmissible and determines a hemolysin-bacteriocin, whereas pAD2 is non-conjugative and determines resistance to erythromycin, streptomycin, and kanamycin. pAD2 could be mobilized by pAD1, but usually involved formation of a pAD1-pAD2 cointegrate.     

Electrolysis and thermolysis for permanent hair removal

The historical, legal, and theoretical aspects and clinical technics of both electrolysis and thermolysis are critically reviewed. The pitfalls of electronic tweezers and the dangers of self-electrolysis are discussed. Complications of electrolysis and thermolysis and the pathophysiology of hair regrowth are presented. In the United States, the lack of uniform training requirements and standards for electrologists may pose an unrecognized risk to public health. It is suggested that more responsible state legislation be enacted in order to decrease the present potential threat to the public health and safety.     

Medical and vocational rehabilitation of patients with microinvasive cancer of the cervix uteri after organ-sparing surgery

The report discusses the data on rehabilitation of 198 cases of cervical carcinoma in situ following conoid diathermoexcision versus the end results. Organ-saving procedures were shown to considerably cut down duration of treatment, to help restore working ability within relatively short period and to keep generative function intact.