Oligonucleotide (GTG)5 as an epidemiological tool in the study of nontuberculous mycobacteria

Analysis of restriction fragment length polymorphisms in the genome of Mycobacterium tuberculosis (DNA fingerprinting) has proved to be a useful epidemiological tool in the study of tuberculosis within populations or communities. However, to date, no similar method has been developed to study the epidemiology of nontuberculous mycobacteria (NTM). In this communication, we report that a simple oligonucleotide repeat, (GTG)5, can be used to accurately genotype all species and strains of NTM tested. We suggest that this technology is an easily applied and accurate tool which can be used for the study of the epidemiology of NTM.     

S-phase fraction identifies high-risk subgroups among DNA-diploid breast cancers

The prognostic value of DNA content measured by means of flow cytometry was analyzed in formalin-fixed, paraffin-embedded samples from 231 breast cancer patients treated between 1984 and 1988, with a mean follow-up period of 55 months. We followed the guidelines of a Consensus Meeting held on this issue in Maine, USA, in 1992. DNA-diploid and -aneuploid tumors were evaluated separately for the fraction of cells in S-phase (SPF) contained in them, this being divided into three groups ('high', 'intermediate', and 'low'), defined by the 25th and 75th centile of the SPF-distribution corresponding to either DNA-diploid or DNA-aneuploid tumors. Unequivocally readable histograms were obtained from 174 samples (75.3%). A high SPF in diploid tumors was significantly associated with a higher recurrence rate (p = 0.015), a shorter disease-free survival (p = 0.014), advanced (IIIB) clinical stage (p = 0.034), and almost significantly with total survival (p = 0.055). In a multivariate Cox regression analysis, a high SPF in diploid tumors retained its independent prognostic power, being significantly associated with a shorter disease-free survival (p = 0.00049) and total survival (p = 0.0077). It also allowed to identify a subgroup with an ominous prognosis among patients < or = 50 years of age with early stage tumors. Our results fully validate the recommendations of the 1992 Maine Consensus Meeting.     

Monocyte-macrophages, granulocyte-macrophage colony-stimulating factor, and prolonged survival among patients with acute myeloid leukemia and stem cell transplants

Recombinant GM-CSF has been recently shown to prolong survival of elderly patients with acute myeloid leukemia (AML) by reducing the rate of induction therapy-related mortality. In a prospective, randomized, placebo-controlled, double-blind, multicenter study conducted by the Eastern Cooperative Oncology Group in the United States, granulocyte-macrophage colony-stimulating factor (GM-CSF) was given only to those patients who had hypocellular or remission marrow on day 10 of one or two cycles of standard induction therapy. Although the administration of GM-CSF significantly reduced a wide range of adverse events, the main benefit of this cytokine seems to be mediated by a reduction in sepsis. A similarly designed study, conducted by the Southwest Oncology Group in a directly comparable AML patient population with use of granulocyte colony-stimulating factor (G-CSF) as the supportive cytokine, showed no survival benefit and no reduction in the rates of serious or lethal sepsis. In most current clinical situations, GM-CSF and G-CSF are indistinguishable both in terms of efficacy and toxicity. GM-CSF and G-CSF have very different impacts on the survival of patients with AML. The stimulation of monocyte-macrophage function and proliferation by GM-CSF may mediate the selective benefit of GM-CSF in patients with AML and stem cell transplants. GM-CSF merits further study as therapy for and/or protection against opportunistic sepsis in patients with cancer and will be included in a number of International Oncology Study Group protocols.     

Modified in situ perfusion of the kidney using balloon catheters

Experiences with the in situ hypotherme perfusion in the operative treatment of calculus in kidneys and calices are reported. A modified technique is presented using an inflatable Swan-Ganz-ballon catheter for simultaneous blocking of renal blood flow and perfusion.     

Management of persistent filtering cicatrix following cataract extraction

We used a safe and simple surgical technique in the management of persistent filtering cicatrices after cataract extraction. The edematous, friable filtering cicatrix was excised entirely and a healthy fornix-based conjunctival flap was sutured over the fistula. Invariably, the fistula was very small, usually only large enough to admit a 27-gauge needle. Of the 27 eyes treated with this technique, there were two failures, but no other complications.