Plasma levels of ionized and total calcium during storage of citrated platelet concentrate

Measurements of ionized and total calcium levels in supernatant plasma samples from citrated platelet concentrates (PCs) were made over 7 days of storage. Both ionized and total calcium increased significantly during the storage period: respectively, from 0.074 mM Ca2+ in fresh platelet-rich plasma to 0.084 mM in PCs stored for 7 days (p = 0.017), and from 1.94 mM total calcium to 2.06 mM (p = 0.014) over the same period. The increase in calcium was partially blocked by the addition of platelet activation inhibitors to the PCs. Platelet-poor plasma stored under similar conditions showed no significant change in ionized or total calcium, which indicated that the increases observed in PCs were due to the release of cellular calcium. Significant correlations (p less than 0.01) were found between ionized or total calcium levels and lactate concentration or pH, but not hypotonic shock recovery rate. The demonstration of non-zero levels of ionized calcium makes it likely that Ca2+-dependent enzyme systems such as calpain expression and thrombin generation are active in the plasma of citrated PCs and may contribute to the platelet storage lesion.     

Identification of the membrane glycoprotein that is the C3b receptor of the human erythrocyte, polymorphonuclear leukocyte, B lymphocyte, and monocyte

A human erythrocyte membrane glycoprotein of 205,000 mol wt (gp205) has been identified as the C3b receptor of the erythrocyte, polymorphonuclear leukocyte (PMN), B lymphocyte, and monocyte. Initially, gp205 was sought and characterized as a constituent of the human erythrocyte membrane that can impair activation of the alternative complement pathway by inducing loss of function of the properdin-stabilized amplification C3 convertase (C3b,Bb,P) through displacement of Bb from C3b and by promoting cleavage-inactivation of C3b by C3b inactivator. These inhibitory activities of gp205 suggested that this membrane glyeoprotein had an affinity for C3b and prompted an analysis of its possible identity as the C3b receptor of human peripheral blood cells. The F(ab’)2 fragment of rabbit IgG anti-gp205 inhibited the formation of rosettes with sheep EC3b of human erythroeytes, B lymphocytes, monocytes and PMN in a dose-response manner; the 50 percent inhibitory doses were 0.13/μg/ml, 0.90 μg/ml, 1.25 μg/ml, and 1.20 μg/ml of F(ab’)2, respectively. Anti-gp205 did not impair the formation of rosettes by monocytes and B lymphocytes with sheep EC3bi or with EC3d. Scatchard analysis of the number of specific (125)I-F(ab’)(2) anti-gp205 binding sites/cell revealed 950 sites/erythrocyte, 21,000 sites/cell of B lymphocyte preparation, 57,000 sites/PMN, and 48,000 sites/monocyte, indicating that the higher concentrations of antibody that had been required for inhibition of rosette formation by the nucleated cells reflected larger numbers of receptors on these cells. Direct evidence for the identity of gp205 as the C3b receptor of the four cell types was obtained when detergent-solubilized membrane proteins of the surface-radioiodinated cells were reacted with anti- gp205 and the immunoprecipitate was analyzed by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. In each instance, the antigenic material reacting with anti-gp205 represented a single protein with an apparent 205,000 mol wt. Thus, gp205 is the C3b receptor of human erythrocytes, PMN, B lymphocytes, and monocytes.     

International Salmonella Typhimurium DT104 infections, 1992-2001

The incidence of multidrug-resistant (MDR) Salmonella Typhimurium infections in humans, and in particular MDR definitive phage type 104 (DT104), has increased substantially in many countries in the last 2 decades, often associated with increased illness. To examine the magnitude of this problem, a survey was conducted among countries with available antimicrobial resistance or phage typing surveillance data. A total of 29, primarily industrialized, countries participated in the survey, which covered the years 1992-2001. Overall, the incidence of MDR S. Typhimurium and DT104 increased continuously during this period, although the problem affected primarily Europe and North America. The increase appeared to have peaked in the United Kingdom but not in other countries. Also, the incidence of quinolone-resistant S. Typhimurium was increasing. This survey implies that MDR S. Typhimurium constitutes an increasing public health problem in large parts of the world and emphasizes the importance of surveillance and control programs.     

Morphological and molecular characteristics of living human fetuses between Carnegie stages 7 and 23: immunolocalization of inhibin {alpha} and {beta}a subunits

Transforming growth factor (TGF) is known to have the abilityto modify mitogenic responses of tissues to other peptide growthfactors and therefore may contribute to the rapid growth rateof an embryo. Throughout the TGF superfamily there is a similarfundamental molecular architecture. Included in this superfamilyare inhibin A, activin A and activin B. It has been shown thatactivin is a powerful mesodermal inducing factor in the earlyembryo. The human embryo has shown localization of inhibin inthe gonads after 16 weeks gestation but it has not been previouslyidentified in earlier embryos. The inhibin-activin protein wasfound in a range of tissues including the liver stages 19-21() and stages 19-22 (ß); oesophagus stages 19-22 (and ß); stomach stages 21 and 22 ( and ß);gut stages 16-22 () and 21 and 22 (ß); pericardiumstages 12-22 ( and ß); gonad stages 21 and 22 (ß)stage 22 (); adrenal stages 19-22 ( and ß); urogenitalsystem states 21 and 22 ( and ß); yolk sac stage 12( and ß); mesenchyme stages 16-22 (); surface ectodermstages 13-22 () and stages 16-22 (ßa); notochord stages13-22 (ß) and stages 21 and 22 (); nasal, tracheaand bronchi stages 19-22 ( and ß) leading to speculationof the role of both subunits.     

Linkage studies of non-syndromic recessive deafness (NSRD) in a family originating from the Mirpur region of Pakistan maps DFNB1 centromeric to D13S175 [published erratum appears in Hum Mol Genet 1996 May;5(5):710]

Autosomal recessive non-syndromal hearing impairment (NSRD) is genetically heterogeneous. Five loci have been identified to date which map to chromosomes 13 (DFNB1), 11 (DFNB2), 17 (DFNB3), 7 (DFNB4) and 14 (DFBN5). We report definite linkage of NSRD to the locus DFNB1 in a single family of 27 families studied of Pakistani origin. Haplotype analysis of markers in the pericentromeric region of chromosome 13q revealed a recombination event which maps DFNB1 proximal to the marker D13S175 and in the vicinity of D13S143.      

Morphological and molecular characteristics of living human fetuses between Carnegi stages 7 and 23: localization of inhibin mRNA {alpha} and {beta}a subunits by in-situ hybridization

Localization of the mRNA and ßa subunits of inhibinhas previously been reported in the human gonads during thesecond trimester. Adrenal inhibin has also been reported inthe second trimester for the ßa and ßbsubunits. Investigations showing localization by in-situ hybridizationduring the first trimester have not been reported. The resultshave shown hybridization of the and ßa subunits,throughout the period of development studied, in a variety oftissues including the dorsal and thoracic aortas and pericardiumstages 13-22 (ßa subunit); liver stages 19-21 (ßa)and stages 21-22 (); mesonephros stages 21 and 22 (ßa);gonad stages ( and ßa); adrenal stages 19-22 (); surfaceectoderm stages 16-22 (ßa); mesenchyme stages 16-22(ßa); amnion stages 13-16 (ßa); yolk sacstage 12 ( and ßa); cartilage stages 19-22 (ßa);and nasal proliferation stages 21 and 22 (ßa). Whencompared with distribution of the protein subunits it was notedthat more immunostaining activity was found, suggesting thatprobes were not sufficiently sensitive enough to detect alllevels of mRNA expressed. It can be surmised, therefore, thatthe lack of visual hybridization of the mRNA cannot precludethe possibility that it is not being translated within the tissueeven though hybridization was not apparent.     

The antimicrobial resistance patterns and associated determinants in Streptococcus suis isolated from humans in southern Vietnam, 1997-2008

Background

Our objective was to determine the frequency and determinants of presentation to care with advanced HIV disease in patients who discover their HIV diagnosis at this stage as well as those with delayed presentation to care after HIV diagnosis in earlier stages.

Methods

We collected data on 1,819 HIV-infected patients in Brussels (Belgium) and Northern France from January 1997 to December 2007. "Advanced HIV disease" was defined as CD4 count <200/mm³ or clinically-defined AIDS at study inclusion and was stratified into two groups: (a) late testing, defined as presentation to care with advanced HIV disease and HIV diagnosis ≤6 months before initiation of HIV care; and (b) delayed presentation to care, defined as presentation to care with advanced HIV disease and HIV diagnosis >6 months before initiation of HIV care. We used multinomial logistic regression to determine the factors associated with delayed presentation to care and late testing.

Results

Of the 570 patients initiating care with advanced HIV disease, 475 (83.3%) were tested late and 95 (16.7%) had delayed presentation to care. Risk factors for delayed presentation to care were: age 30-50 years, injection drug use, and follow-up in Brussels. Risk factors for late testing were: sub-Saharan African origin, male gender, and older age. HIV transmission through heterosexual contact was associated with an increased risk of both delayed presentation to care and late testing. Patients who initiated HIV care in 2003-2007 were less likely to have been tested late or to have a delayed presentation to care than patients who initiated care before 2003.

Conclusion

A considerable proportion of HIV-infected patients present to care with advanced HIV disease. Late testing, rather than a delay in initiating care after earlier HIV testing, is the main determinant of presentation to care with advanced HIV disease. The factors associated with delay presentation to care differ from those associated with late testing. Different strategies should be developed to optimize early access to care in these two groups.     

A case of pulmonary vein obstruction: evaluation using newer echocardiographic imaging techniques

A 59-year-old woman was admitted in our hospital due to persistentcough and dyspnea. Transthoracic 2-dimensional echocardiographydemonstrated a cardiac mass (29x34 mm) that extended from theright upper pulmonary vein into the left atrium causing thepartial obstruction of the right lower vein as indicated bythe increased Doppler velocities. Contrast echocardiographyconfirmed the presence of microcirculation within the mass.During transesophageal (TEE) echocardiographic study, colorDoppler imaging and power Doppler imaging (Angio^® Vivid7, GE Medical System, Horten, Norway) demonstrated the presenceof vascular flow within the mass. A chest magnetic resonancetomography showed a pulmonary mass of 30x25x28 mm infiltratingthe pulmonary veins. After surgery, biopsy confirmed a highgrade mucoepidermoid lung cancer with few large arterioles.The new echocardiographic techniques can reliably differentiatea cardiac tumor from a cardiac thrombus.