Characterization of erythrocyte quality during the refrigerated storage of whole blood containing di-(2-ethylhexyl) phthalate

Di-(2-ethylhexyl) phthalate (DEHP) accumulates in blood brought into contact with materials utilizing this compound as a plasticizer. To determine whether this phthalate diester affects red blood cell integrity, we have compared cell morphology, plasma hemoglobin accumulation, micro-vesicle production, and the concentration of intracellular metabolites and electrolytes of erythrocytes from blood stored at 4 degrees C with and without DEHP. When sufficient emulsified DEHP was mixed with blood to give a final concentration of 300 micrograms/mL, plasma hemoglobin accumulation was reduced by an average of 70%, the percentage of cells exhibiting normal morphology was enhanced by at least 20-fold, and the volume of microvesicles released from red blood cells was reduced by 50% after 35 days of refrigerated storage compared to the values obtained from corresponding samples stored without added phthalate. Similar effects were observed regardless of whether blood was stored in nonplasticized polypropylene or tri-(2-ethylhexyl) trimellitate plasticized polyvinylchloride containers and with DEHP solubilized by a variety of emulsifiers. When 300 micrograms/mL DEHP was added to stored blood containing erythrocytes predominantly in the echinocyte conformation, many of the cells reverted to the normal discoid morphology. The addition of this quantity of DEHP to blood had no significant effect on the course of storage-induced changes in erythrocyte adenosine triphosphate (ATP), 2,3-diphosphoglycerate (2,3-DPG), sodium or potassium concentrations. The data are consistent with the hypothesis that DEHP inhibits the deterioration of the red blood cell membrane that results from the refrigerated storage of whole blood.     

Targeting appropriate interventions to minimize deterioration of drinking-water quality in developing countries

In developing countries, it has been observed that drinking-water frequently becomes recontaminated following its collection and during storage in the home. This paper proposes a semi-quantified 'disease risk index' (DRI) designed to identify communities or households that are 'most at risk' from consuming recontaminated drinking-water. A brief review of appropriate physical and educational intervention measures is presented, and their effective use is discussed. It is concluded that incorporating a simple appraisal tool, such as the proposed DRI, into a community water-supply programme would be useful in shaping the overall strategy requiring only a minimum of organizational learning.     

Direct and indirect costs of tuberculosis among immigrant patients in the Netherlands

Background  

In low tuberculosis (TB) incidence countries TB affects mostly immigrants in the productive age group. Little empirical information is available about direct and indirect TB-related costs that patients face in these high-income countries. We assessed the direct and indirect costs of immigrants with TB in the Netherlands.     

The emerging syndrome of envenoming by the New Guinea small-eyed snake Micropechis ikaheka

The New Guinea small-eyed or Ikaheka snake, <it>Micropechis ikaheka</it>, which occurs throughout New Guinea and some adjacent islands, is feared by the indigenes. The first proven human fatality was in the 1950s and this species has since been implicated in many other cases of severe and fatal envenoming. Reliable attribution of envenoming to this species in victims unable to capture or kill the snake recently became possible by the use of enzyme immunoassay. Eleven cases of proven envenoming by <it>M. ikaheka</it>, with two fatalities, were identified in Papua New Guinea and Irian Jaya. Five patients showed no clinical signs of envenoming by other Australasian elapids: mild local swelling, local lymphadenopathy, neurotoxicity, general myalgia, spontaneous systemic bleeding, incoagulable blood and passage of dark urine (haemoglobinuria or myoglobinuria). Two patients developed hypotension and two died of respiratory paralysis 19 and 38 h after being bitten. <it>In vitro</it> studies indicate that the venom is rich in phospholipase A2, is indirectly haemolytic, anticoagulant and inhibits platelets, but is not procoagulant or fibrinolytic. It shows predominantly post-synaptic neurotoxic and myotoxic activity. Anecdotally, Commonwealth Serum Laboratories' (CSL) death adder antivenom has proved ineffective whereas CSL polyvalent antivenom may be beneficial. Anticholinesterase drugs might prove effective in improving neuromuscular transmission and should be tested in patients with neurotoxic envenoming.      

Difficult mammographic needle localizations: use of alternate orthogonal projections

Lesions deep within the breast are occasionally visible on only one standard mammographic projection and are therefore difficult to localize preoperatively. Such abnormalities can often be visualized on two orthogonal 45 degrees oblique views. In these cases, needle localizations may be performed in a routine manner without computed tomography or stereotactic methods.     

Involvement of sinoaortic afferents in renal sympathoinhibition and vasodilation induced by acute hypernatremia

Despite the abundance of evidence that supports the important role of aortic and carotid afferents to short‐term regulation of blood pressure and detection of variation in the arterial PO₂, PCO₂ and pH, relatively little is known regarding the role of these afferents during changes in the volume and composition of extracellular compartments. The present study sought to determine the involvement of these afferents in the renal vasodilation and sympathoinhibition induced by hypertonic saline (HS) infusion. Sinoaortic‐denervated and sham male Wistar rats were anaesthetised with intravenous (i.v.) urethane (1.2 g/kg body weight (bw)) prior to the measurement of the mean arterial pressure (MAP), renal vascular conductance (RVC) and renal sympathetic nerve activity (RSNA). In the sham group, the HS infusion (3 mol/L NaCl, 1.8 mL/kg bw, i.v.) induced transient hypertension (12 ± 4 mmHg from baseline, peak at 10 min; P < 0.05), an increase in RVC (127 ± 9% and 150 ± 13% from baseline, at 20 and 60 min respectively; P < 0.05) and a decrease in RSNA (?34 ± 10% and ?29 ± 5% from baseline, at 10 and 60 min respectively; P < 0.05). In sinoaortic‐denervated rats, HS infusion promoted a sustained pressor response (30 ± 5 and 17 ± 6 mmHg of baseline values, at 10 and 30 min respectively; P < 0.05) and abolished the increase in RVC (85 ± 8% from baseline, at 10 min) and decrease in RSNA (?4 ± 3% from baseline, at 10 min). These results suggest that aortic and carotid afferents are involved in cardiovascular and renal sympathoinhibition responses induced by acute hypernatremia.     

The Measurement of Reticuloendothelial Iron Release using Iron–Dextran

An index of reticuloendothelial cell release of iron for erythropoiesis can be derived from simultaneous measurements of iron—dextran and transferrin-bound iron utilization. Reticuloendothelial iron release was found to be reduced in patients with Hodgkins disease, chronic renal failure and some cases of rheumatoid arthritis. It was increased in patients with iron deficiency.