Prognostic importance of structural chromosomal abnormalities in children with hyperdiploid (greater than 50 chromosomes) acute lymphoblastic leukemia

Approximately one fourth of children with newly diagnosed acute lymphoblastic leukemia (ALL) have hyperdiploid (greater than 50 chromosomes) blasts and a relatively favorable prognosis. Nonetheless, a substantial proportion of these patients fail therapy. We studied 138 children (70 male, 68 female) with hyperdiploid greater than 50 ALL to assess initial clinical and cytogenetic features that might predict treatment failure. In 85 of these cases (62%), structural chromosomal abnormalities were also present; clinical and laboratory features in this group did not differ from those of the 53 cases with only numeric abnormalities. However, of the 28 failures seen at a median follow-up of 4 years, 22 occurred in cases with structural chromosomal abnormalities (P = .03 by Breslow test). In a multivariate analysis, only the presence of structural chromosomal abnormalities and male gender were independently associated with treatment failure. Structural chromosomal abnormalities in cases of ALL with greater than 50 chromosomes may define a biologically different form of leukemia characterized by increased likelihood of drug resistance.     

Nonrandom involvement of the 12p12 breakpoint in chromosome abnormalities of childhood acute lymphoblastic leukemia

We studied the presenting clinical and biologic features of 23 children with acute lymphoblastic leukemia (ALL) whose leukemic marrow karyotypes contained abnormalities involving the short arm of chromosome 12. Nineteen of the abnormalities were assigned to the 12p12 breakpoint. The median age of the children was 5 years (range 2 to 13 years) and their initial leukocyte counts ranged from 1,800 to 424,000/microL (median 30,000/microL). Twenty-one patients (91%) had common phenotype ALL (CALLA+, HLA-DR+), including three cases with a pre-B cell phenotype (CIg+). The remaining two cases were T cell in origin. The French-American-British (FAB) morphologic type of lymphoblastic leukemia was L1 in all cases but one. With a median follow-up of 11 months, four patients have relapsed and another failed induction therapy. The modal chromosome number in all cases was less than 50. Three distinct cytogenetic patterns, with apparently similar clinical manifestations, were noted: terminal deletions of chromosome 12 in 10 cases, apparently balanced reciprocal translocations in 6, and unbalanced translocations in 7. All translocations were between the 12p arm and different donor chromosomes except for chromosomes 7, 9, and 17, which participated twice. Only two patients had identical translocations: t(7;12)(q11;p12). This unusual variation in donor chromosomes and breakpoints suggests that translocations involving the 12p are specific with respect to only one member of the translocation pair, namely chromosome 12. The relatively high frequency of the 12p abnormalities in this study (10% of all completely banded cases seen over a 35-month period) warrants further investigation.     

Placeboaspekte der Arzt-Patienten-Beziehung

In medicine, placebos are used both in scientific studies and for practical therapeutic purposes. In evidence-based medicine, the efficacy of treatment may be determined as the difference between the effects of the verum (the active study drug) and the placebo, the latter being a substance lacking specific action on the disease under consideration. However, the improvements in patients' conditions under placebo treatment may be substantial and comparable to those with verum. Genuine placebos predominate in clinical studies, while pseudoplacebos prevail in practical therapy. The term pseudoplacebo can also be applied to many procedures in complementary medicine, including homeopathic medicine (Büchel et al., Placebo in der Medizin, 2011). The comprehensive definition of placebo, as used in a report by the German Medical Association (Büchel et al., Placebo in der Medizin, 2011), states that a placebo effect may occur even when treating with verum. The placebo effect is modulated by the context of the treatment, by the expectations of the patients and the doctors, and by the success of the relationship between doctors and patients. A number of unspecific effects, e.g., spontaneous alleviation, statistical effects, variance with time, methodological errors, in addition to the placebo effect make up the total response that is called"placebo reaction." A complete list of the effectiveness of placebo for all important diseases is still lacking. Further, it is not possible to predict which patients will respond to placebo. Which characteristics of doctors are important (competence, empathy, communicative ability and partnership, trust) in order to achieve a placebo effect, particularly in addition to the verum effect measures of evidence-based medicine? Are there doctors who are better in this than others? Could the nocebo effect weaken the efficacy of treatment in evidence-based medicine? Since a placebo effect may occur in almost any standard therapy, information about placebos should be provided during medical education and continuing medical education (CME). The use of placebo in clinical studies is ethically justified and lawful in consenting patients if there is no other effective treatment available with which the test substance could be compared. For daily practical therapeutic purposes, placebos may be ethically acceptable and lawful if there is no effective therapy available, if the complaints are minor, if the patient expressly wishes treatment, and if there is a reasonable likelihood of success. However, an explanation of the expected benefits and risks must be provided to the patients. At present, there are two explanatory theories for the mechanism of action of placebo, namely, the associative and the mentalistic explanation (Büchel et al., Placebo in der Medizin, 2011). Interestingly, effects of placebo and of verum can be localized in the brain by physiological and anatomical techniques. With many open questions remaining, research on placebo is currently very active. These aspect and neurobiological findings in particular may facilitate for "scientifically" educated doctors to accept that ineffective materials, i.e., placebos, are in fact effective.     

EFFECT OF SUBCLINICAL LEAD INTOXICATION ON LARYNGEAL CANCER

SUMMARY In this study we investigated the possible relationship of laryngeal cancer and subclinical lead intoxication, using the depression of aminolevulinic acid dehydratase (ALAD) activity in blood as indicator. Twenty-six patients with laryngeal cancer and 53 normal controls met the criteria to enter the study. Blood ALAD activity values in the patients with laryngeal cancer ranged from 27.1 to 75.3 U/l with a mean of 50.79 U/l. The respective values in the control group ranged from 36.2 to 98 U/l with a mean of 59.76 U/l. There was a statistically significant difference between the two means (0.001 <p<0.01), whereas blood lead concentrations in all patients were within normal limits. These findings support the hypothesis that low level lead intoxication (subclinical blood lead levels), from cars, industries and products, may contribute to the risk of laryngeal cancer. Further investigation is needed to clarify the exact relationship between lead and cancer of the larynx.     

The Staphyloccous aureus Eap protein activates expression of proinflammatory cytokines

The extracellular adhesion protein (Eap) secreted by the major human pathogen Staphylococcus aureus is known to have several effects on human immunity. We have recently added to knowledge of these roles by demonstrating that Eap enhances interactions between major histocompatibility complex molecules and human leukocytes. Several studies have indicated that Eap can induce cytokine production by human peripheral blood mononuclear cells (PBMCs). To date, there has been no rigorous attempt to identify the breadth of cytokines produced by Eap stimulation or to identify the cell subsets that respond. Here, we demonstrate that Eap induces the secretion of the proinflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) by CD14(+) leukocytes (monocytes and macrophages) within direct ex vivo PBMC populations (note that granulocytes are also CD14(+) but are largely depleted from PBMC preparations). Anti-intercellular adhesion molecule 1 (CD54) antibodies inhibited this induction and implicated a role for this known Eap binding protein in cellular activation. IL-6 and TNF-alpha secretion by murine cells exposed to Eap was also observed. The activation of CD14(+) cells by Eap suggests that it could play a significant role in both septic shock and fever, two of the major pathological features of S. aureus infections.