Biventricular support using a centrifugal pump in a 6 year old with fulminant myocarditis

We experienced a case of ventricular assist with both a pulsatile-flow and a continuous-flow pump in a pediatric patient, and herein report the clinical course and characteristics of the pumps. A 6-year-old female was diagnosed with fulminant myocarditis and transferred to our hospital for mechanical support. After 12 days of extracorporeal membrane oxygenation, we implanted a left ventricular assist device (LVAD) and a right ventricular assist device (RVAD) using centrifugal Gyro pumps with a membrane oxygenator in a paracorporeal fashion. The membrane oxygenator was removed on postoperative day (POD) 4, and the patient was weaned from the respirator on POD 6. The LVAD was exchanged on POD 13 and 17, and the RVAD was exchanged on POD 14 because of thrombus formation inside the pumps. The RVAD was removed on POD 25. On POD 32, the patient experienced cerebral infarction and the centrifugal Gyro pump was switched to an extracorporeal pulsatile pump. No thromboembolic event occurred after pump conversion, although continuous administration of vasodilators was required to avoid hypertension. She underwent successfully heart transplantation in the USA after 8 months of ventricular support. A centrifugal pump is considered useful for pediatric patients, as pump flow and blood pressure can be relatively easily controlled in the postoperative acute phase compared with the pulsatile pump. However, special care should be taken to monitor for thrombus formation when support length becomes longer than 13 days, and a switch to a pulsatile pump should be considered once the hemodynamic status stabilizes.     

Flow cytometric detection of HLA antibodies using a spectrum of microbeads

We describe here the use of HLA antigen coated beads for specificity and class determination of HLA antibodies by flow cytometry. The HLA specificity of antibodies was determined by use of beads containing eight levels of fluorescence. HLA antigens isolated from eight cultured cells were coated onto these beads so that each bead was the equivalent of one cell. By using four sets of eight beads, an equivalent of 32 cells could be examined in four test tubes. A total of 76 class I and 25 class II specificities could be determined by the 32 class I bead-panel and 32 class II bead-panel used, respectively. We noted no cross-reactivity of reactions between class I and II. The sensitivity of the test was shown to be higher than that of the standard cytotoxicity by dilution experiments and detection of additional cross-reacting antigens. By use of these coated beads, we achieved improved standardized detection of HLA antibodies. Antigen-coated beads have several advantages over the use of spleens or lymphocytes. (a) A highly selected panel of antigens can be routinely used. (b) Class I and class II antibodies can be readily distinguished from each other, even when they are present as mixtures in one serum. (c) Non-HLA antibodies are not detected because the beads do not have any other antigens than HLA on them. (d) The quantity of antigens coated on beads is more uniform than that found in cells from different individuals. (e) Beads are more convenient for storage and daily use.     

Survival and axonal regeneration of off-center retinal ganglion cells of adult cats are promoted with an anti-glaucoma drug, nipradilol, but not BDNF and CNTF

OFF-center retinal ganglion cells (RGCs) occupy a smaller proportion than ON RGCs when RGCs regenerate axons into a transplanted peripheral nerve. We examined whether the regeneration ability of OFF RGCs in adult cats was promoted when the numbers of regenerating RGCs were increased with brain-derived neurotrophic factor (BDNF)+ciliary neurotrophic factor (CNTF)+forskolin (BCF) or 3,4-dihydro-8-(2-hydroxy-3-isopropylamino)-propoxy-3-nitroxy-2H-1-benzopyran (nipradilol), an anti-glaucoma drug. ON or OFF RGCs were morphologically determined on the basis of their dendritic ramification in the inner plexiform layer using computational analysis. In the normal intact retina the ratio of ON and OFF RGCs (ON/OFF ratio) was 1.25 (55%/44%); whereas, it was 2.61 in regenerating RGCs with saline injection (control) 6 weeks after peripheral nerve transplantation. Estimated numbers of regenerating ON and OFF RGCs were 2149 and 895, respectively. An injection of BCF increased only numbers of ON RGCs into 5766 (2.7-fold to control) but not that of OFF RGCs, n=858. Nipradilol increased both estimated numbers of ON (11,518, 5.4-fold to control) and OFF RGCs (7330, 8.2-fold to control). In the retinas with optic nerve (OpN) transection and intravitreal saline-, BCF- or nipradilol-injection, numbers of ON and OFF RGCs surviving axotomy showed similar trend to that in regenerating RGCs. Thus, nipradilol promoted the survival and regeneration abilities of both of ON and OFF RGCs whereas BCF only did the abilities of ON RGCs. The distribution of tropo-myosin-related kinase B, BDNF receptor, was sparser in the outer two thirds of inner plexiform layer. The lower surviving ability of OFF-RGCs may be attributed in part to the distribution.     

Mother and daughter with 45,X/46,X,r(X)(p22.3q28) and mental retardation: analysis of the X-inactivation patterns

We report on a mother and daughter both with a 45,X/46,X,r(X)(p22. 3q28) karyotype and mental retardation. Fluorescence in situ hybridization (FISH) and microsatellite analyses for 14 loci/region at Xp22.3 and seven loci/region at Xq28 indicated that the ring X chromosome was missing a roughly 12-Mb region from Xp22.3 with the breakpoint between DXS85 and DXS9972, and another region of less than 100 kb from Xq28 with the breakpoint distal to the region defined by the FISH probe c8.2/1. X-inactivation analysis, using the methylation status of the AR gene (exon 1) as an indicator, showed that the normal and ring X chromosomes in the X,r(X)(p22.3q28) cell lineage were randomly inactivated. The Xp22.3 deleted region partially overlaps with the regional intervals of MRX19, MRX21, MRX24, MRX37, MRX43, and MRX49 associated with heterozygote manifestation. Therefore, it is likely that one or more of these MRX genes, subject to X-inactivation, are lost from the ring X chromosome, and that reduced expression of the MRX gene(s) caused by random X-inactivation has resulted in mental retardation in the mother and daughter.     

Hilar cholangiocarcinoma with extensive immunoglobulin G4 reaction

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is a systemic fibroinflammatory disorder that can involve multiple organs. It is often challenging to distinguish IgG4-related sclerosing cholangitis (IgG4-SC) from cholangiocarcinoma because of overlap in their clinical findings. A 75-year-old man presented to a hospital for a detailed examination of the elevation of some biliary enzymes. Radiographic examination revealed segmental bile duct with wall thickening of the common hepatic bile duct, and dilation of the peripheral branches. Transampullary biopsy showed a non-specific inflammatory reaction with several IgG4-positive cell infiltrations. There were no signs of malignancy. The liver biopsy showed bile duct injury accompanied by IgG4-positive cell infiltration. We then performed bile duct biopsy and finally diagnosed the patient with cholangiocarcinoma. We should remember that the IgG4 reaction is neither completely sensitive nor specific for IgG4-RD and avoid resting solely on the IgG4 reaction to precisely distinguish IgG4-SC from cholangiocarcinoma.     

Experimental lupus nephritis in severe combined immunodeficient (SCID) mice: remodelling of the glomerular lesions by bystander IgM antibodies

MRL/Mp-lpr/lpr (MRL/lpr) mice develop glomerular lesions with regular variations in their histopathological manifestations, similar to those in lupus nephritis. These lesions are mainly either cell-proliferative or wire loop-like and are associated with glomerular deposits of immunoglobulins, most frequently IgG and IgM. We previously established a nephritogenic IgG3-producing hybridoma clone, B1, from an MRL/lpr mouse, which induces only a 'wire loop-like' type of glomerular lesion when injected into SCID mice. Injection of SCID mice with an anti-trinitrophenyl IgM antibody-producing hybridoma clone, Sp6, following injection of the B1 clone, however, resulted in the development of a 'cell-proliferative' type of glomerular lesion, associated with an accumulation of both antibodies in glomeruli. This accumulation occurred even though Sp6 IgM antibodies did not react with B1 IgG3 antibodies and vice versa. A mutant clone of Sp6, T/13microE/3.1, which produces antibodies deficient in C1q binding, produced a similar effect as that of the Sp6 clone, i.e. 'cell-proliferative' lesions. Again the B1 antibodies did not react with T/13microE/3. 1-IgM antibodies and vice versa. We therefore conclude that bystander IgM antibodies contribute to the remodelling of glomerular lesions in situ, following glomerular injury by the nephritogenic antibodies.     

Mother and daughter with 45,X/46,X,r(X)(p22.3q28) and mental retardation: Analysis of the x‐inactivation patterns

We report on a mother and daughter both with a 45,X/46,X,r(X)(p22.3q28) karyotype and mental retardation. Fluorescence in situ hybridization (FISH) and microsatellite analyses for 14 loci/region at Xp22.3 and seven loci/region at Xq28 indicated that the ring X chromosome was missing a roughly 12‐Mb region from Xp22.3 with the breakpoint between DXS85 and DXS9972, and another region of less than 100 kb from Xq28 with the breakpoint distal to the region defined by the FISH probe c8.2/1. X‐inactivation analysis, using the methylation status of the AR gene (exon 1) as an indicator, showed that the normal and ring X chromosomes in the X,r(X)(p22.3q28) cell lineage were randomly inactivated. The Xp22.3 deleted region partially overlaps with the regional intervals of MRX19, MRX21, MRX24, MRX37, MRX43, and MRX49 associated with heterozygote manifestation. Therefore, it is likely that one or more of these MRX genes, subject to X‐inactivation, are lost from the ring X chromosome, and that reduced expression of the MRX gene(s) caused by random X‐inactivation has resulted in mental retardation in the mother and daughter. Am. J. Med. Genet. 91:267–272, 2000. © 2000 Wiley‐Liss, Inc.     

Incidence and role of antibody in graft injury: How can it best be monitored?

Alloantibodies, either preexisting or de novo developed, are associated with hyperacute, acute, and chronic rejection. Human leukocyte antigens (HLAs) are one of the major causal contributors of recipient antibody response. The average percent posttransplant antibodies specific for HLAs is 14.2% in 113 lung, 19.3% in 278 liver, 20.9% in 3,979 kidney, and 22.8% in 393 heart transplant recipients with a functioning graft. Within 1-year of follow-up, 21 of 244 (8.6%) antibody-positive patients experienced graft rejection, which is significantly higher than that found in an HLA antibody-negative patient group (43/1421*100% = 3%, P = .00003). Other polymorphic antigens such as MHC class I—related chain and endothelial cell-specific antigens are also capable of inducing antibody responses related to allograft rejection. The mechanism of antibody-mediated allograft rejection remains controversial; however, endothelial cells are considered the primary target of antibody-mediated rejection. Most pathological changes can be interpreted as a result of vascular damage and ensuing pathological compensation including tissue repair. Because alloantibody is closely correlated to rejection, we advise that posttransplant antibody be monitored. The most commonly used antibody detection techniques and their advantages and disadvantages are discussed in detail.     

Comparison of a new heparin-coated dense membrane lung with nonheparin-coated dense membrane lung for prolonged extracorporeal lung assist in goats

Thrombosis and bleeding are major complications in cases of prolonged extracorporeal lung assist (ECLA) with an artificial-membrane lung. Antithrombogenic treatment of the artificial-membrane oxygenator and circuits is indispensable for safe ECLA. The efficacy of a new heparin-coated membrane lung with minimal systemic heparinization was evaluated for 7 days and compared with a nonheparin-coated membrane lung in goats. The animals were randomly assigned to either the heparin-coated membrane group (HM group, n = 5) or nonheparin-coated membrane group (NHM group, n = 5). Activated coagulation time (ACT) during ECLA was controlled to below 150 s in the HM group, and to near 200 s in the NHM group. All goats in the HM group were sustained on ECLA for 7 days, but two goats in the NHM group died on the 4th and 6th days, respectively. The mean systemic administration rate of heparin during ECLA was 22.4 +/- 4.4 U/kg/h in the HM group and 39.0 +/- 10.0 U/kg/h in the NHM group. There was a significant difference between the two groups (P < 0.05). The oxygen transfer rate, the Pco(2) difference, the perfusion resistance, and platelet counts showed no significant changes. There was no plasma leakage from the artificial lung. Although several clots were observed in the stagnant areas of the artificial lung, they did not lead to deterioration of the function of the artificial lung. The excellent antithrombogenicity, gas exchange ability, and durability of this new artificial lung with circuits might contribute to successful prolonged ECLA with minimal systemic heparinization.