Clearance kinetics of parasites and pigment-containing leukocytes in severe malaria

In tropical areas, where unsupervised use of antimalarial drugs is common, patients with an illness consistent clinically with severe malaria but with negative blood smears pose a management dilemma. Malaria pigment is evident in peripheral blood leukocytes in greater than 90% of patients with severe malaria. To characterize the clearance kinetics of parasitized erythrocytes and malaria pigment-containing leukocytes, sequential peripheral blood and intradermal smears were assessed in 27 adult Vietnamese patients with severe falciparum malaria. The clearance of parasitized erythrocytes and pigment- containing monocytes (PCMs) followed first order kinetics. The elimination of pigment-containing neutrophils (PCNs) was first order initially, but deviated from this when counts were low. Clearance of peripheral blood PCMs (median clearance time, 216 hours; range, 84 to 492 hours) was significantly slower than that of parasitized erythrocytes (median, 96 hours; range, 36 to 168 hours) or PCNs (median, 72 hours; range, 0 to 168 hours; P < .0001). Intradermal PCM clearance times were the longest of all (median, 12 days; range, 6 to 23 days; significantly longer than peripheral blood PCM clearance, P < .001). Twenty-one (88%) patients still had signs, symptoms, or laboratory features of severe malaria after parasite clearance but before phagocyte pigment clearance. Sixteen of the 23 surviving patients (70%; 95% confidence interval, 50% to 87%) still had intraleukocytic malaria pigment on peripheral blood films 72 hours after parasite clearance. Thus, by determining the distribution of malaria pigment in peripheral blood and intradermal phagocytes, the time since effective antimalarial treatment started can be estimated. Microscopy for intraleukocytic pigment is valuable in the differential diagnosis of severe febrile illnesses in malarious areas where uncontrolled use of antimalarial drugs is widespread.     

Evaluation and comparison of three mobilization methods for the collection of granulocytes

BACKGROUND: Cancer chemotherapeutic regimens have become more potent and myeloablative. As a consequence, morbidity and mortality due to opportunistic infections have become a major challenge. The provision of adequate doses of viable granulocytes has thus become an important approach for circumventing the problem. A schedule for collecting therapeutic numbers of cells with minimal donor toxicity has yet to be established. STUDY DESIGN AND METHODS: An investigation of three mobilization schedules for the collection of granulocytes for transfusion–granulocyte-colony-stimulating factor (G-CSF) 5 micrograms per kg daily; G-CSF 5 micrograms per kg every other day, and prednisone 60 mg given orally (20 mg doses at 17 hours, 12 hours, and 2 hours before the collection). RESULTS: A total of 464 apheresis procedures involving 163 healthy donors were analyzed. Prednisone caused a small increase in the white cell (WBC) counts over the collection days, while G-CSF every other day and daily schedules improved WBC counts to 145 and 160 percent, respectively (p = 0.004). Similarly, administration of G-CSF daily and every other day mobilized higher yields of granulocytes over the collection days, compared to the prednisone schedule (170% and 180% vs. 105%; p = 0.02). CONCLUSION: Compared with prednisone, higher WBC yields were achieved by G-CSF stimulation; G-CSF given every other day is as effective as daily G-CSF administration for the recruitment of granulocytes, which makes the mobilization procedure more cost- effective.     

Reasons for non-compliance with screening for infection with Helicobacter pylori, in a multi-ethnic community in Leicester, UK

In this study, we aimed to identify reasons for non-compliance with a screening programme for Helicobacter pylori (H pylori), in a multi-ethnic community and to assess the effectiveness of Asian language materials towards increasing compliance. A serological screening test for infection with H pylori was offered to 200 Asians and 200 non-Asians (mainly Europeans), aged 21–55 y, registered at a single general practice. Reasons for non-attendance for screening were identified by reply slip or interview. A second group of 200 Asians who were offered screening were sent information in Gujarati as well as English. When information was mailed in English only, 30% Asians and 22% non-Asians attended (P = 0.09, ns). Stated reasons for non-attendance in the Asian group were not generally language related; reasons were similar in the Asian and non-Asian groups and were most frequently related to other commitments. The use of materials in Gujarati did not improve compliance.Language problems should not be assumed to dominate reasons for non-compliance with screening in ethnic minority groups. In common with those of UK origin, subjects from ethnic minority groups may more generally have insufficient interest in preventive medicine for them to prioritise health screening above other commitments.     

Separation of lipid and water MR imaging signals by chopper averaging in the time domain

A convenient alternative to Dixon's water/lipid imaging technique is proposed. The sequence exploits the automatic paired averaging capability that is used in commercial magnetic resonance imaging systems for data averaging to achieve lipid suppression. This can be easily implemented via a minor modification to an existing partial saturation sequence. This approach provides linear suppression of lipid signals that is independent of the relative abundance of water and lipid contributions, unlike the characteristics of the original Dixon sequence. The proposed sequence can be tuned before the imaging procedure to ensure optimum timing and frequency adjustment.     

FS03.4Irritant dermatitis following tape stripping

The aim of the study was to compare the effects of a SLS toothpaste formulation with and without betaine on skin and oral mucosa using electrical bioimpedance (IMP). Two groups, in total 47 participants, were recruited. In the skin group (27 participants) four test sites on the volar forearms were used: SLS paste, SLS + betaine paste, betaine paste, and one unoccluded control site. In the oral group (20 participants) the same toothpaste formulations were used. The test substances were applied in 12 mm Finn chambers for 24 hours at randomised test sites on the skin, and in 18 mm Finn chambers for 15 minutes on the oral mucosa. Visual examination and readings with IMP were taken before application and 24 hours after removal of the chambers for the skin, and for the oral mucosa before and 15 minutes after exposure. Information was extracted from the impedance spectra using four indices based on magnitude and phase at 2 frequencies, emphasising different aspects of the impedance properties of the tissues. The SLS‐containing pastes showed for both skin and oral mucosa some positive visual grade 1 reactions. Significant changes were found for the impedance indices, and the reaction patterns of the indices differed between the skin and the oral mucosa. We conclude that very slight reactions of skin and oral mucosa are detected by IMP. Furthermore, betaine containing toothpaste does not irritate neither skin nor oral mucosa, but the effect together with SLS is insignificant.