Monocyte chemotaxis and chemotactic cytokine release after exposure to hydroxyethyl starch

Hydroxyethyl starch (HES) is commonly used in leukapheresis and infused as an alternative to blood components for the treatment of hypotension due to hemorrhage and trauma. Its prolonged intravascular persistence and retention in tissue raise concerns about possible effects on humoral and cell-mediated immunity and white cell (WBC) locomotion, particularly in volunteer WBC donors or in severely burned individuals with immunologic depression and increased risk for infection. This study evaluated the effect of HES on human monocyte migration and chemotaxis and the production of antigen- and mitogen-induced WBC-derived chemotactic cytokine. A bioassay was developed to quantitate the neutrophil chemotactic activity of a cytokine generated by mononuclear WBCs stimulated in vitro by phytohemagglutinin or tuberculin protein. The time- and dose-dependent generation of the chemotactic cytokine was not affected by the presence of HES. HES by itself did not induce the generation of this cytokine, nor were human monocyte chemotaxis and spontaneous migration significantly changed by exposure to HES. These results, with those of other investigators, suggest that HES is a safe red cell-sedimenting agent for leukapheresis and an alternative to the use of blood components in shock resuscitation.     

Bedside filtration of blood products in the prevention of HLA alloimmunization--a prospective randomized study. Alloimmunisation Study Group

To test the efficacy of poststorage bedside leucodepletion of blood products in the prevention of primary HLA alloimmunization and its clinical sequelae, 172 patients with hematologic malignancy requiring intensive red blood cell and platelet support were randomized to receive either standard or filtered red blood cells and platelets. Quality control of bedside filtration was explored by sequential sampling downstream of the filter, but this did not predict the total number of leucocytes transfused. After exclusions, 123 evaluable patients were assessed every two weeks until the end of therapy. HLA antibodies developed in 21 of 56 (37.5%) nonfilter (NF) and 15 of 67 (22%) filter (F) patients (risk ratio estimate, 0.60 [95% confidence interval, 0.34 to 1.05]; P = .07). Patients with acute myeloid leukemia (AML; n = 53) had higher alloimmunization rates in both arms of the study, with a greater effect of filtration (62.5% NF and 31.0% F; P = .025). Bedside filtration did not affect the overall incidence of febrile transfusion reactions (FTRs; 37% NF and 34% F; P = .71) or of platelet refractoriness assessed in 50 patients (30% NF and 26% F), despite an association between broad HLA reactivity and both FTRs and refractoriness. However, FTRs were also seen in 28 patients without HLA antibodies. Five alloimmunized refractory patients (2 F and 3 NF) required HLA-selected platelets. This report, the first prospective study of bedside filtration, has failed to show clear clinical benefit. Methodological limitations may account in part for this failure, notably the difficulties in accurately assessing the number of leucocytes transfused.     

A simple approach to prenatal diagnosis of beta-thalassemia in a geographic area where multiple mutations occur

We describe a simple approach for detecting beta-thalassemia mutations in geographic areas such as southern China where multiple mutations are known to occur. Segments of the beta-globin gene were amplified in vitro by using the polymerase chain reaction. Dot blot hybridization of the amplified DNA with oligonucleotide probes corresponding to the six mutations found in southern China could directly identify the mutations causing beta-thalassemia in the affected families. The increased number of target sequences after amplification allows the use of 35S-labeled probes, which are reusable for up to 3 months. The mutations can be determined in two days.     

Calculated bioavailable testosterone levels and depression in middle-aged men

BACKGROUND: The association between circulating total testosterone (TT) levels and depressive symptoms remains unclear. We sought to determine the relationship between physiologically active bioavailable testosterone (BT) and depressive symptoms in middle-aged men with and without major depressive disorder (MDD). METHODS: We assessed and compared calculated BT levels in two groups of middle-aged men (40-65 years): untreated subjects meeting DSM-IV-TR-defined criteria for a major depressive episode as part of major depressive disorder (N=44) and a matched non-depressed control group (N=50). RESULTS: Depressed men had lower mean BT levels (3.51+/-1.69 vs. 4.69+/-2.04 nmol/L; p=0.008) and TT levels (11.94+/-4.63 vs. 17.64+/-1.02 nmol/L; p<0.001) when compared to the control group. Biochemical hypogonadism (i.e., BT level< or =2.4 nmol/L or TT level< or =12.14 nmol/L) was also more prevalent in depressed men vs. non-depressed controls (34% vs. 6%, p<0.001; 61% vs. 14%, p<0.001, respectively). CONCLUSIONS: Changes in physiologically active BT concentration may be a vulnerability factor for depressive symptoms in middle-aged depressed men.     

Decreases in procalcitonin and C-reactive protein are strong predictors of survival in ventilator-associated pneumonia

Introduction  

This study sought to assess the prognostic value of the kinetics of procalcitonin (PCT), C-reactive protein (CRP) and clinical scores (clinical pulmonary infection score (CPIS), Sequential Organ Failure Assessment (SOFA)) in the outcome of ventilator-associated pneumonia (VAP) at an early time point, when adequacy of antimicrobial treatment is evaluated.     

Sleep studies and supportive ventilatory treatment in patients with congenital muscle disorders

Eight ambulant children aged 6-13 years, four with congenital myopathy, two with congenital muscular dystrophy and two with the rigid spine syndrome, presented with recurrent chest infections, morning headaches, shallow breathing at night, or respiratory failure. Polysomnography confirmed the presence of nocturnal hypoxaemia with oxygen saturation on average less than 90% for 49% of sleep and less than 80% for 19% of sleep accompanied with severe hypoventilation. Additionally there was sleep disturbance characterised by an increased number of wake epochs from deep sleep (in comparison to 10 non-hypoxaemic subjects). The severity of sleep hypoxaemia did not correlate with symptoms. Treatment with night time nasal ventilation was started and repeat polysomnography showed normal overnight oxygen saturation and a reduced number of wake epochs during deep sleep. It is important to be vigilant for sleep hypoventilation in these patients and sleep studies should be part of the routine respiratory evaluation. Treatment with nasal ventilation is effective in reversing the nocturnal respiratory failure without significant disturbance to life style.