Human metapneumovirus RNA in encephalitis patient

We describe a fatal case of encephalitis that might be correlated with primary human metapneumovirus (HMPV) encephalitis. Postmortem HMPV RNA was detected in brain and lung tissue samples from the patient. Furthermore, HMPV RNA was found in culture fluids from cells coincubated with lung tissue.     

Uremia accelerates both atherosclerosis and arterial calcification in apolipoprotein E knockout mice

Chronic renal failure (CRF) favors the development of atherosclerosis and excessive calcification of atheromatous lesions. CRF was induced in apolipoprotein E knockout (apoE(-/-)) mice to study (1) a possible acceleration of aortic atherosclerosis, (2) the degree and type of vascular calcification, and (3) factors involved in the calcification process. For creating CRF, 8-wk-old apolipoprotein E gene knockout (apoE(-/-)) mice underwent partial kidney ablation. Control animals underwent sham operation. Aortic atherosclerotic plaques and calcification were evaluated using quantitative morphologic image processing. At 6 wk after nephrectomy, CRF mice had significantly higher serum urea, cholesterol, and triglyceride concentrations than non-CRF controls. The serum levels of advanced oxidation protein products were elevated in the uremic group and were correlated with serum urea levels. Atherosclerotic lesions in thoracic aorta were significantly larger in uremic apoE(-/-) mice than in nonuremic controls. The relative proportion of calcified area to total surface area of both atherosclerotic lesions and lesion-free vascular tissue was increased in aortic root of uremic apoE(-/-) mice when compared with controls. The calcium deposits were made of hydroxyapatite and calcite crystals. In addition, plaques from uremic animals showed a significant increase in collagen content, whereas the degree of macrophage infiltration was comparable in both groups. There was no difference in mean arterial BP. These findings demonstrate that CRF aggravates atherosclerosis in apoE(-/-) mice. Moreover, CRF enhances arterial calcification at both atheromatous intimal sites and atheroma-free medial sites. We anticipate that this experimental model will be useful to test treatment strategies aimed at decreasing the accelerated atherosclerosis and arterial calcification in uremia.     

Distribution and effects of polymorphic RANTES gene alleles in HIV/HCV coinfection -- a prospective cross-sectional study

AIM: Chemokines and their receptors are crucial for immune responses in HCV and HIV infection. RANTES gene polymorphisms lead to altered gene expression and influence the natural course of HIV infection. Therefore, these mutations may also affect the course of HIV/HCV coinfection. METHODS: We determined allele frequencies of RANTES-403 (G→A), RANTES-28 (C→G) and RANTES-IN1.1 (T→C) polymorphisms using real-time PCR and hybridization probes in patients with HIV (n = 85), HCV (n = 112), HIV/HCV coinfection (n = 121), and 109 healthy controls. Furthermore, HIV and HCV loads as well as CD4+ and CD8+ cell counts were compared between different RANTES genotypes. RESULTS: Frequencies of RANTES-403 A, RANTES-28 G and RANTES-IN1.1 C alleles were higher in HIV infected patients than in healthy controls (-403: 28.2% vs 15.1%, P = 0.002; -28: 5.4% vs 2.8%, not significant; IN1.1: 19.0% vs 11.0%, P = 0.038). In HIV/HCV coinfected patients, these RANTES alleles were less frequent than in patients with HIV infection alone (15.4% P = 0.002; 1.7%; P = 0.048; 12.0%; not significant). Frequencies of these alleles were not significantly different between HIV/HCV positive patients, HCV positive patients and healthy controls. CONCLUSION: All three RANTES polymorphisms showed increased frequencies of the variant allele exclusively in patients with HIV monoinfection. The finding that the frequencies of these alleles remained unaltered in HIV/HCV coinfected patients suggests that HCV coinfection interferes with selection processes associated with these alleles in HIV infection.     

Eosinophilic differentiation of the human promyelocytic leukemia cell line, HL-60

HL-60 promyelocytic leukemia cells differentiated to eosinophils and eosinophilic precursors when cultured under mildly alkaline conditions (pH 7.6-7.8) for 7 d without refeeding. New cytoplasmic granules appeared blue in the least mature cells and red in the most mature cells when stained with Wright-Giemsa. The granules also stained with Luxol-fast-blue, a characteristic of eosinophil granules. Furthermore, most cells contained the eosinophil major basic protein (MBP); the Charcot-Leyden Crystal (CLC) protein (lysophospholipase), eosinophil peroxidase, acid phosphatase, and arylsulfatase were also detected in a portion of these cells. The eosinophil major basic protein was found in a high proportion of undifferentiated cells, and thus may be constituitively produced. By examining finely banded chromosomes, translocation break points were demonstrated at q22 on one chromosome 16 and at q23 on the other homologue; abnormalities in this region of the long arm of 16 are a characteristic finding in the recently described syndrome of acute myelomonocytic leukemia (AMMoL) with abnormal bone marrow eosinophils. In common with the bone marrow eosinophils in these patients, the HL-60 eosinophil granules contained chloroacetate esterase and periodic-acid Schiff (PAS) reactive material; crystalloid inclusions were rare. Therefore, the HL-60 cell line appears to be an in vitro model for eosinophilopoiesis and may be specially suited for the study of the abnormal eosinophils seen in certain malignant conditions.     

Effect of oral contraceptives on the anticoagulant activity of protein S in plasma

We determined anticoagulant parameters that depend on protein S function in plasma, i.e. the APC-independent anticoagulant activity of protein S (expressed as pSR) and APC resistance determined with thrombin generation-based tests (expressed as APCsr) as well as plasma levels of total and free protein S and prothrombin in men, women not using oral contraceptives (OC), and in women using second or third generation OC. Thrombin generation in the APC resistance assays was initiated either with factor Xa (Xa-APCsr) or tissue factor (TF-APCsr). The APC-independent anticoagulant activity of protein S was highest in men (pSR=1.69) and gradually decreased from women not using OC (pSR=1.49) via women using second generation (pSR=1.35) to women using third generation OC (pSR=1.27). The pSR correlated inversely with nAPCsr determined with the tissue factor-based APC resistance test (TF-APCsr) but not with nAPCsr determined with the factor Xa-based assay (Xa-APCsr). Multiple linear regression analysis in which sex, OC use, and protein S and prothrombin levels were included as independent variables and the pSR, TF-APCsr or Xa-APCsr as dependent variables indicated that plasma protein S levels poorly predict the pSR and the TF-APCsr, but are the main determinant of the Xa-APCsr. This indicates that OC use alters the expression of protein S activity. This phenomenon can be caused by differences in modulation of the activity of protein S by other plasma proteins that change during OC use or by OC-induced changes in the protein S molecule that impair its anticoagulant activity. Functional impairment of protein S as a result of hormonal influence may, at least in part, contribute to the thrombotic risk of OC users.     

Agreement of a new whole-blood PT/INR test using capillary samples with plasma INR determinations

PURPOSE: The objective of the study was to compare in anticoagulated patients the international normalized ratio (INR) measured with a new capillary whole-blood device, the i-STAT Portable Clinical Analyser, with conventional plasma INR obtained from the central laboratory. PATIENTS AND METHODS: Between-cartridge variability was first determined with two lyophilized controls with INR levels of 1.60 and 2.75 (n=10). Next, in 35 patients under different intensities of oral anticoagulation, capillary blood INR was measured with two i-STAT devices and was compared to central laboratory plasma INR (Innovin reagent and BCS analyser). RESULTS: Between-cartridge coefficients of variation were 5% (95%, CI 3.4-9.1) and 3% (95%, CI 2.1-5.5) at INR levels of 1.60 and 2.75. Mean INR difference between the two i-STAT devices was 0.1, and the correlation coefficient was 0.98. Between i-STAT and central laboratory INR, the correlation coefficient was 0.95. Bias values were 0.04, 0.2, and -0.04 at INR levels of 2.0, 2.5, and 3.5, respectively. CONCLUSION: The INR measured with the i-STAT Portable Clinical Analyser is precise and compares well with plasma INR performed in a central laboratory.     

Serum antibodies against the hepatitis C virus E2 protein mediate antibody-dependent cellular cytotoxicity (ADCC)

BACKGROUND/AIMS: The role of antibody dependent cellular cytotoxicity (ADCC) in HCV infection is unclear at present. Antibodies mediating ADCC are usually directed against viral envelope proteins. As cell surface expression of the HCV envelope E2 protein has been shown, the HCV E2 protein is an especially promising candidate target for ADCC. METHODS: Sera from patients with acute (n=6), self-limited (n=11) and chronic (n=19) HCV infection were analyzed in this study. Sera reacting with cell-bound HCV antigens were examined in a flowcytometric cytotoxicity assay using antigen-coated JOK-1 cells as targets. RESULTS: We found that sera from all stages of HCV infection reacted with cells loaded with HCV E2. E2-specific ADCC was observed in patients with acute (n=3/6), self-limited (n=5/11) and chronic (n=13/19) hepatitis C and was closely related to fluorescence intensity in the E2-binding assay (r=0.67, P<0.001). CONCLUSIONS: We conclude that E2-antibodies from all stages of HCV infection can mediate ADCC. Thus, the role of this process in the pathogenesis of chronic hepatitis C should be further elucidated.     

The effect of epidural analgesia in labour on maternal respiratory function

Lumbar epidural analgesia during labour has gained widespread acceptance. The impact of epidural analgesia based on mixtures of low-dose local anaesthetic solutions and lipophilic opioids on most clinically relevant obstetric outcomes is minimal. Since the pregnant state per se is associated with important alterations in respiration, we assessed whether a subtle degree of motor blockade brought about by epidural analgesia might compromise respiratory function as assessed by spirometry. Sixty consenting parturients receiving epidural analgesia were consecutively included in this prospective study. We performed spirometry during the antepartum visit and in labour after effective epidural analgesia was established; at both assessments the women were pain-free. Values were within normal ranges but increased significantly after effective epidural analgesia; median (IQR [range]) increase for vital capacity 7.4 (3.0-13 [-12-27])% (p < 0.001); forced vital capacity 4.4 (1.7-9.8 [-13-26])% (p < 0.001); forced expiratory volume in 1 s 5.5 (1.7-8.6 [-14-28])% (p < 0.001); and peak expiratory flow rate 2.3 (-1.6-5.8 [-18-16])% (p = 0.01)). We conclude that epidural analgesia for labour significantly improved respiratory function.     

The effect of common origin of the carotid arteries in neurologic outcome after neonatal ECMO

Background

Common origin of the carotid arteries (COCA) is a normal anatomic variant reported to occur in approximately 11% of the general population. The objective of this study was to determine whether this variant places venoarterial extracorporeal membrane oxygenation (ECMO) patients at a higher risk for adverse neurologic sequelae owing to potential occlusion of both carotid arteries by the arterial cannula.

Methods

The authors reviewed clinical records and echocardiograms of the initial 220 ECMO patients at their institution. Aortic arch morphology was determined by a pediatric cardiologist blinded to all other data. After exclusion of predetermined patients, 131 patients were divided into 2 groups: those with separate origin of the carotid arteries (n = 111) and those with COCA (n = 20). The neurologic outcome variables studied included the results of magnetic resonance imaging (MRI); computed tomography (CT); electroencephalogram (EEG); brainstem auditory-evoked response (BAER), head ultrasound scan, and Bayley Scales of Infant Development reported as Psychomotor Developmental Index (PDI) and Mental Developmental Index (MDI).

Results

COCA had no predictive value in determining PDI and MDI outcomes and no significance in predicting an increased risk of adverse neurologic sequelae based on MRI, CT, EEG, BAER, or head ultrasound scan.

Conclusions

This study confirms that COCA is a common aortic arch variant (15%, n = 20 of 131) and that this variant does not appear to increase the risk of neurologic injury in infants undergoing venoarterial ECMO.