Different perforin expression in peripheral blood and prostate tissue in patients with benign prostatic hyperplasia and prostate cancer.

Perforin (P) is a prototypical cytotoxic molecule involved in cell-mediated immunity against various pathogens, alloantigens and particularly different tumours. The purpose of this study was to determine P expression in different lymphocyte subpopulations isolated from peripheral blood and prostate tissue of patients with benign prostatic hyperplasia (BPH) and prostate cancer (PCa) and compare it with the P expression found in the control group. Twenty subjects were recruited in each of the groups. Prostate mononuclear cells of the BPH and PCa tissues were isolated by enzymatic digestion and gradient density centrifugation, whereas peripheral blood mononuclear cells were isolated by gradient density centrifugation alone. Cells and tissue samples were labelled using monoclonal antibodies against P and different surface antigens (CD3, CD4, CD8 and CD56) and analysed by immunofluorescence and flow cytometry. Total P expression in peripheral blood lymphocytes did not differ significantly between BPH/PCa patients and control group, although the BPH and PCa tissue showed lower P expression level. A negative correlation between prostate-specific antigen levels and the overall percentage of P(+), CD3(+) CD56(-) P(+) , and CD3(-) CD56(+) P(+) cells in the prostate tissue was observed only in patients with PCa. Our findings indicate that the low frequency of P(+) lymphocytes, including T, NKT and NK cells, in the prostate tissue of patients with BPH and, particularly, PCa could be the consequence of local tissue microenvironment and one of the mechanisms involved in the pathogenesis of prostate hyperplasia following malignant alteration.

Amikacin treatment of Serratia septicemia in critically ill patients.

Serratia marcescens septicemia represents a serious problem in high risk critical care patients. Treatment is difficult because Serratia is usually resistant to most antibiotics. Amikacin is at present the most effective antibiotic in vitro against gentamycin-resistant Serratia, although significant loss of activity may occur in vivo in the group of compromised patients, whose ultimate prognosis may depend eventually upon other associated conditions. In this Medical ICU, 15 patients with Serratia septicemia who were treated with in vitro effective antibiotics (14 were given amikacin) had a mortality of 60%, while 5 patients who received ineffective in vitro antibiotics had a mortality of 100%. In this ICU, 80% of the Serratia isolates were resistant to gentamycin, while only 2.8% were resistant to amikacin. Because amikacin-resistant strains of Serratia have already emerged, appropriate use of this antibiotic is essential in order not to promote the selection of amikacin-resistant strains.

Association of a low serum albumin with infection and increased mortality in critically ill patients.

214 patients among 282 consecutive admissions had at least one measurement of serum albumin (SA) during their stay on the ICU and were classified according to their lowest value of SA. Mean SA was 2.88 /+- 0.74 g/100 mg. Survivors had a mean SA (3.18 /+- 0.60) higher than non-survivors (2.35 /+- 0.68 g/100 ml) (p < 0.05). 64% of patients were admitted with an abnormally low SA (less than 3.5 g/100 ml) and in 56% of these the initial value was higher than the last. Mortality increased in the groups with lower SA and the level of SA was associated with infection (x2 = 73.9) and mortality (x2 = 69.7) (p < 0.05). The percentage of infected patients who died increased in groups with lower SA.