How to use a nasopharyngeal prong in Pierre Robin sequence

Pierre Robin sequence (PRS) describes a small mandible with retrognathia, an elevated and posteriorly positioned tongue, and an associated U-shaped cleft palate. The retracted tongue may obstruct the airway leading to respiratory failure, with failure to thrive and adverse neurodevelopmental outcomes if not addressed. If the airway obstruction cannot be overcome with conservative measures, there are non-surgical and surgical options. A nasopharyngeal prong (NPP) is a non-surgical, temporary treatment that avoids the complications inherent in an operation, especially given the natural history of mandibular growth and improved airway obstruction in PRS. Although the use of a prong requires training, support, and follow up, it effectively bypasses the obstruction in the majority of children with PRS, and allows the child to outgrow the airway obstruction until the prong is no longer required. On average, the prong can be removed between 6 and 12 months of age.     

Patient-specific transfusion-related acute lung injury

Transfusion-related acute lung injury (TRALI) is one of the leading causes of transfusion-associated mortality. The inadvertent transfusion of neutrophil antibodies can cause pulmonary transfusion reactions and TRALI. However, not all patients transfused with neutrophil antibodies experience transfusion reactions. A 22-year-old man with severe aplastic anaemia (SAA) experienced TRALI after a platelet transfusion. The donor was found to be alloimmunized to human neutrophil antigen (HNA)-3a, an antigen expressed by neutrophils from approximately 90% of Caucasians. Eleven other platelet components from this donor were transfused prior to this event and two caused reactions: one chills and one TRALI. Both episodes of TRALI occurred in the same male patient with SAA. The fact that one patient experienced TRALI following both exposures to anti-HNA-3a from the same donor whereas nine other recipients did not adds evidence to the observation that patient factors make a significant contribution to neutrophil antibody-mediated transfusion reactions.     

Differential CD26-mediated activation of the CD3 and CD2 pathways after CD6-depleted allogeneic bone marrow transplantation

Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes.     

Fc gamma receptor II (CD32) on malignant B cells influences modulation induced by anti-CD19 monoclonal antibody

Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies.     

Outcomes and risks of granulocyte colony-stimulating factor in patients with coronary artery disease.

OBJECTIVES: Cytokine mobilization of progenitor cells from bone marrow may promote myocardial neovascularization with relief of ischemia. BACKGROUND: Patients with coronary artery disease (CAD) have low numbers of endothelial progenitor cells compared with healthy subjects. METHODS: Granulocyte colony-stimulating factor (G-CSF), 10 microg/kg/day for five days, was administered to 16 CAD patients. Progenitor cells were measured by flow cytometry; ischemia was assessed by exercise stress testing and by dobutamine stress cardiac magnetic resonance imaging. RESULTS: Granulocyte colony-stimulating factor increased CD34+/CD133+ cells in the circulation from 1.5 +/- 0.2 microl to 52.4 +/- 10.4 microl (p < 0.001), similar to the response observed in 15 healthy subjects (75.1 +/- 12.6 microl, p = 0.173). Indices of platelet and coagulation activation were not changed by treatment, but C-reactive protein increased from 4.5 +/- 1.3 mg/l to 8.6 +/- 1.3 mg/l (p = 0.017). Two patients experienced serious adverse events: 1) non-ST-segment elevation myocardial infarction (MI) 8 h after the fifth G-CSF dose, and 2) MI and death 17 days after treatment. At 1 month after treatment, there was no improvement from baseline values (i.e., reduction) in wall motion score (from 25.7 +/- 2.1 to 28.3 +/- 1.9, p = 0.196) or segments with abnormal perfusion (7.6 +/- 1.1 to 7.7 +/- 1.1, p = 0.916) and a trend towards a greater number of ischemic segments (from 4.5 +/- 0.6 to 6.1 +/- 1.0, p = 0.068). There was no improvement in exercise duration at 1 month (p = 0.37) or at 3 months (p = 0.98) versus baseline. CONCLUSIONS: Granulocyte colony-stimulating factor administration to CAD patients mobilizes cells with endothelial progenitor potential from bone marrow, but without objective evidence of cardiac benefit and with the potential for adverse outcomes in some patients.     

Enhanced Bone Regeneration Using Porcine Small Intestinal Submucosa

Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material.     

Monoclonal antibodies recognizing epitopes on the extracellular face and intracellular N-terminus of the human erythrocyte anion transporter (band 3) and their application to the analysis of South East Asian ovalocytes

This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.