Donor-derived acute promyelocytic leukemia in a liver-transplant recipient.
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Bone Marrow Cells↗
Biomedical subjects
J Hess
Publications and source records attributed to J Hess.
[Magnetic resonance imaging and spiral computed tomography in the diagnosis and follow-up of adults with congenital heart and vessel disease].
Management of patients with congenital heart disease requires detailed information on cardiac and great vessel morphology. In previous years the diagnosis and treatment of congenital malformations often depended on cardiac catheterization and in many institutions cardiac catheterization still remains the gold standard against which other modalities are measured. In the past decade, however, imaging methodologies have increasingly shifted toward the use of less invasive and noninvasive techniques. Currently, echocardiography is the initial method of choice in evaluating the anatomy, especially in younger patients. Meanwhile, several newer imaging techniques like magnetic resonance imaging (MRI) and computed tomography (CT) are in use. They offer extremely useful information about abnormalities of the heart and great vessels as well as for the assessment of cardiac anatomy and function. Echo, angiography, MRT and CT should be seen as complementary investigations in adult congenital heart disease.
Adult↗
[Interventional catheter occlusion of the atrial septal defect of the secundum type--experiences with "CardioSeal" and "Angel Wings"].
Between July 1996 and July 1998, 34 patients (female n = 16, male n = 18) were scheduled for catheter--interventional occlusion (ASDO) of an atrium septum defect of secundum type (ASD II). Median age was 7.9 years (2.5-54.6), weight 23.1 kg (9-97). 9 defects were closed with "Angel Wings" (AW) and 25 ASD occlusions were attempted with "CardioSeal" (CS). 30 patients had simple ASD II, 3 persisting foramen ovale with suspected paradoxal cerebral embolization and 1 significant residual shunt at atrial level after corrective heart surgery for interrupted aortic arch type B. ASDO was successful in 31/34 cases (91%). One CS was removed surgically due to significant left to right shunt after release and two CS devices were withdrawn back into the sheath. Median ASD diameter was 11.9 mm (6-16), balloon occlusive diameter was 15 mm (6-20) and median left to right shunt was 40% (6-64%). On follow up minimal left to right shunt was seen in 5/31 patients (16%). In selected patients catheter--interventional ASDO may be a good alternative to surgical ASD closure.
Adolescent↗
Impact of intracellular location of and antigen display by intracellular bacteria: implications for vaccine development.
Intracellular bacteria are primarily controlled by T-lymphocytes. The 'phagosomal' bacteria such as Salmonella enterica and Mycobacterium bovis BCG remain in the phagosome. These microbes primarily stimulate CD4 T-cells via antigen presentation through MHC class II molecules. In contrast, Listeria monocytogenes egresses from the phagosome into the cytoplasm by virtue of listeriolysin. This 'cytoplasmic' pathogen is controlled by CD8 T-cells through MHC class I antigen presentation. Some bacterial pathogens such as Mycobacterium tuberculosis presumably remain in the phagosome but apparently 'perforate' the phagosomal membrane and thus stimulate both CD4 and CD8 T-cells. We have constructed S. enterica and M. bovis BCG vaccine carriers which secrete listeriolysin. Such constructs are capable of introducing antigens into the MHC class II and MHC class I pathway, resulting in stimulation of both CD4 and CD8 T-cells. Moreover, we constructed S. enterica vaccines which display one and the same listerial antigen in secreted and somatic form. Secreted antigen display was found to be superior to somatic antigen display. Hence, we consider antigen secretion a major prerequisite of an effective vaccine against intracellular bacteria.
Animals↗
Delivery of DNA vaccines by attenuated intracellular bacteria.
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Animals↗
The need for a novel generation of vaccines.
Although empirical vaccine development was highly successful, it has now reached its limits. Vaccines are only efficacious against those pathogens which are primarily controlled by antibodies. Protection against many infectious agents, however, strongly depends on T lymphocytes. Thus, novel vaccines have to stimulate the combination of T lymphocytes that is required for an optimum protective immune response. Although identification of antigens remains crucial, novel vaccine design also needs to consider the best way of introducing these antigens to the immune system. Intracellular antigen compartmentalisation, the early cytokine milieu and the appropriate surface expression of co-stimulatory molecules are of major relevance for understanding how novel vaccines could induce a protective immune response mediated by T lymphocytes. Intracellular bacteria are controlled by T lymphocytes and efficacious vaccines against these pathogens are not available yet. In this treatise, two experimental vaccination strategies will be described in more detail. These encompass recombinant vaccine carriers expressing, and naked DNA constructs encoding, heterologous antigens. Both vaccination strategies proved to be protective in the model of experimental listeriosis of mice.
Animals↗
Development of novel tuberculosis vaccines.
Efficacious control of tuberculosis (TB), one of the world's major health threats, is best achieved by a combination of chemotherapy and vaccination. The current vaccine, BCG, fails to prevent pulmonary TB in adults, which is the most prevalent form of this disease. Consequently, the design of novel vaccines against TB is urgently required. Because the acquired immune response is mediated by different T-cell sets, an optimal combination of these populations must be stimulated. As one third of the world's population is already infected with Mycobacterium tuberculosis, two types of vaccine may be required: one for eradication of already established infection and the other for prompt combat of invading microbes. A rational judgement on the efficacy of the different types of vaccine currently under development needs to await further evaluation.
Antigens, Bacterial↗
Introduction of protein or DNA delivered via recombinant Salmonella typhimurium into the major histocompatibility complex class I presentation pathway of macrophages.
Recombinant (r) Salmonella typhimurium aroA strains which display the hen egg ovalbumin OVA(257-264) peptide SIINFEKL in secreted form were constructed. In addition, attenuated rS. typhimurium pcDNA-OVA constructs harbouring a eukaryotic expression plasmid encoding complete OVA were used to introduce the immunodominant OVA(257-264) epitope into the major histocompatibility complex (MHC) class I presentation pathway. Both modes of antigen delivery (DNA and protein) by Salmonella vaccine carriers stimulated OVA(257-264)-specific CD8 T-cell hybridomas. An in vitro infection system was established that allowed both rSalmonella carrier devices to facilitate MHC class I delivery of OVA(257-264) by coexpression of listeriolysin (Hly) or by coinfection with rS. typhimurium Hlys (Hess J., Gentschev I., Miko D., Welzel M., Ladel C., Goebel W., Kaufmann S.H.E., Proc. Natl. Acad. Sci. USA 93 (1996) 1458-1463). Coexpression of Hly and coinfection with rS. typhimurium Hlys slightly improved MHC class I processing of OVA. Our data provide further evidence for the feasibility of attenuated, Hly-expressing rS. typhimurium carriers secreting heterologous antigens or harbouring heterologous DNA as effective vaccines for stimulating CD8 T cells in addition to CD4 T cells.
Amino Acid Sequence↗
Cytolytic T-cell responses to human dendritic cells and macrophages infected with Mycobacterium bovis BCG and recombinant BCG secreting listeriolysin.
Cytolytic T-cell responses from 63 normal blood donors were monitored in a Mycobacterium bovis BCG infection system in vitro. We wanted to know whether cultured dendritic cells were capable of potentiating the cytolytic T-cell responses to M. bovis BCG. Infected cultured dendritic cells were up to ten times more effective antigen-presenting cells than macrophages in proliferative assays, while cytolytic T-cell induction did not differ significantly between dendritic cells and macrophages. Separated CD4+ and CD8+ T-cell subsets contributed equally to lysis of infected targets. Experiments comparing wild-type M. bovis BCG strain with two new recombinant M. bovis BCG strains secreting listeriolysin revealed statistically significant higher maximal lysis values for recombinant M. bovis BCG. We conclude from our in vitro infection system with mycobacteria that dendritic cells are superior to macrophages in proliferative assays but equal to macrophages in their ability to induce cytolytic T-cell responses. Moreover, our data suggest that recombinant M. bovis BCG vaccine strains secreting listeriolysin improve cytolytic T-cell responses.
Antibodies, Monoclonal↗
Cardiovascular aspects of experimental meningococcal sepsis in young and older awake piglets: age-related differences.
Severe meningococcal disease is characterized by: a high load of specific endotoxin, capillary leakage and coagulation disorders. We studied the possible age-related differences in global hemodynamic and regional blood flow responses to different dosages (1 and 10 microg/kg body weight) of rough meningococcal endotoxin in young (8 kg) and older piglets (40 kg). Animals were chronically instrumented and studied in the awake state. The response to plasma infusion (30 mL/kg in 30 min) was evaluated after placebo and endotoxin infusion. The clinical picture was similar in all groups. The mortality was 0/8, 3/8,1/8, 4/9 in young-low, young-high, old-low, and old-high dose respectively. Most important findings were that cardiac index (CI) decreased in the young animals after endotoxin infusion, while it was well preserved in the older animals; in the older animals the systemic vascular resistance dropped 20%, while in the younger ones there was no change in resistance. Conductance to the kidneys, intestines, and spleen decreased significantly more in the young animals, while the increase in conductance and flow to the liver was higher in the old animals; subsequent volume loading resulted only partly in a recovery of the hemodynamic parameters, but failed to improve oxygen delivery.
Age Factors↗
Live antigen carriers as tools for improved anti-tuberculosis vaccines.
Recombinant (r) Mycobacterium bovis BCG strains have been constructed which secrete biologically active listeriolysin (Hly) fusion protein of Listeria monocytogenes. In human and murine macrophage-like cell lines, intracellular persistence of these r-BCG strains was reduced as compared to the parental BCG strain. By immunogold labelling Hly was detected in membrane structures and within the phagosomal space of macrophages. Hly fusions consistently co-localized with a lysosome-associated membrane glycoprotein (LAMP-1) suggesting that membrane attack conformation of Hly was not altered. Although r-BCG microorganisms apparently did not egress into the cytoplasmic compartment of host cells, they both improved major histocompatibility complex class I presentation of co-phagocytosed soluble ovalbumin as compared with wild-type BCG microbes. These data suggest that Hly secretion endows BCG with an improved capacity to stimulate CD8 T cells. Because CD8 T cells play a major role in protection against tuberculosis such Hly-secreting r-BCG constructs are anti-tuberculosis vaccine candidates. In addition, we report on our r-Salmonella typhimurium expression system combined with the HlyB/HlyD/ TolC export machinery for delivering the prominent mycobacterial antigen Ag85B for immune recognition.
Animals↗
Chromosome 22q11 deletions in patients with selected outflow tract malformations.
The incidence of 22q11 deletions and its effect on the phenotype were established in 170 patients with selected outflow tract malformations and transposition of the great arteries (conotruncal defects). Cases were seen both prospectively and retrospectively. All patients had a dysmorphological evaluation by the clinical geneticist and a cytogenetic analysis including FISH analysis for 22q11 deletions. A chromosomal abnormality was present in 29 patients, including a 22q11 deletion in 22/170 patients (13%). The 22q11 deletion was found in 11% of tetralogy of Fallot, in 11% of pulmonary atresia and VSD, in 44% of pulmonary atresia. VSD and collateral arteries, in 20% of truncus arteriosus, in 60% of interrupted aortic arch and in 25% patients with aberrant subclavian artery. They were absent in double outlet right ventricle or in transposition of the great arteries. No parental deletion was found. All patients had clinical characteristics of the velocardiofacial syndrome. This study confirms a high incidence of chromosome 22q11 deletions in patients with selected outflow tract malformations, with great clinical impact for further management and genetic counseling.
Adolescent↗
Left ventricular rhabdomyoma. A case report.
BACKGROUND: Cardiac tumours in infancy are rare, with a predominant incidence of rhabdomyoma. Diagnosis can best be obtained by pre-cordial and transoesophageal echocardiography. Because of the tendency for spontaneous regression conservative therapy is generally recommended. A rare indication for surgical treatment is described. METHODS EXPERIMENTAL DESIGN: case report. SETTING: Pediatric cardiology and cardiac surgery in a university hospital. PATIENT: a case of a rhabdomyoma of the left ventricle is described which was attached to the left ventricular outflow tract and the left coronary cusp of the aortic valve, causing outflow obstruction of the left ventricle. INTERVENTION: the tumour was removed surgically using cardiopulmonary bypass. MEASURE: achievement of relief of left ventricular outflow obstruction. RESULTS: Immediate and complete relief of the left ventricular outflow tract was achieved with preservation of the aortic valve. The patient recovered well. CONCLUSIONS: Cardiac rhabdomyomas can usually be treated conservatively. Surgical therapy can be successfully applied when rhabdomyoma results in hemodynamic problems or arrhythmias.
Echocardiography, Transesophageal↗
Development, characterization, and use of monoclonal antibodies made to antigens expressed on the surface of fetal nucleated red blood cells.
BACKGROUND: Current methods for obtaining fetal cells for prenatal diagnosis are invasive and carry a small (0.5-1.0%) but definite risk of miscarriage. An attractive alternative would be isolation of fetal cells from peripheral maternal blood using antibodies with high specificity and avidity. METHODS: To generate antibodies, we purified nucleated red blood cells (NRBCs) from fetal livers and used them as the immunogen to generate monoclonal antibodies (mAbs) directed against surface antigens. RESULTS: The four antibodies recognized at least two conformationally sensitive epitopes of the transferrin receptor. Isolation of NRBCs from 252 maternal blood samples using these antibodies in magnetic activated cell sorting after an initial density gradient centrifugation yielded 0-419 NRBCs per 25 mL of maternal blood. One antibody, 2B7.4, not only isolated the highest number of NRBCs (>10 in 90% of the samples) but also isolated these NRBCs in 78 consecutive maternal samples. CONCLUSION: Antibody 2B7.4 shows promise for the isolation of NRBCs from maternal blood and should allow studies concerning the source of these cells, fetal vs maternal, and the factors controlling their prevalence.
Animals↗
Mycobacterium bovis Bacille Calmette-Guérin strains secreting listeriolysin of Listeria monocytogenes.
Recombinant (r) Mycobacterium bovis strains were constructed that secrete biologically active listeriolysin (Hly) fusion protein of Listeria monocytogenes. The r-BCG strains pAT261:Hly or pMV306:Hly expressed plasmid multicopies or chromosomal single copies of the hly gene, respectively. Human and murine macrophage-like cell lines were infected with r-BCG pAT261:Hly and pMV306:Hly strains. Interestingly, intracellular persistence of both r-BCG strains was reduced in macrophages as compared with the parental BCG strain. By immunogold labeling Hly was detected in membrane structures and within the phagosomal space of macrophages. In addition, Hly was localized within cytoplasmic vacuoles outside the mycobacteria-containing phagosome of host cells infected with r-BCG pAT261:Hly or r-BCG pMV306:Hly. Hly fusions consistently colocalized with a lysosome-associated membrane glycoprotein, suggesting that membrane-attack conformation of Hly was not altered. Although r-BCG pAT261:Hly and r-BCG pMV306:Hly microorganims apparently did not egress into the cytoplasmic compartment of host cells, they both improved major histocompatibility complex class I presentation of cophagocytosed soluble protein as compared with wild-type BCG microbes. These data suggest that Hly secretion endows BCG with an improved capacity to stimulate CD8 T cells. Because CD8 T cells play a major role in protection against tuberculosis such Hly secreting r-BCG constructs are antituberculosis vaccine candidates.
Amino Acid Sequence↗
[Sudden death in young persons caused by arrhythmogenic right ventricular dysplasia].
A previously healthy boy aged 14 developed persistent ventricular tachycardia while engaged in sports; ultrasonography revealed arrhythmogenic right ventricular dysplasia (ARVD). He was treated with a class III antiarrhythmic drug but nevertheless died 4 years later during recreational activities. An uncle of the boy was found to have died suddenly on a playing field, 25 years previously at the age of 20. In ARVD, fibrolipomatous areas in the right ventricle lead to dilations of the wall where (sometimes fatal) re-entrant tachycardias may develop. An autosomal dominant heredity with variable expression and penetrance is considered probable, while the genetic defect was located recently. Examination and, if necessary, pharmacotherapy of relatives of an ARVD patient may reduce the risk of a fatal arrhythmia.
Adolescent↗
Efficacy of a dry fibrin sealant dressing for hemorrhage control after ballistic injury.
OBJECTIVE: To determine if a dry fibrin sealant dressing (DFSD) will provide superior hemostasis when compared with regular gauze in a ballistic injury animal model. DESIGN: A nonsurvival randomized goat study. SETTING: A federal biomedical research institute. SUBJECTS: Eighteen anesthetized Angora goats. INTERVENTIONS: Uncontrolled hemorrhage was induced by a complex ballistic extremity injury. Control of hemorrhage was achieved by applying and holding pressure with the DFSD or regular gauze for 2 minutes. The dressings were left in place for 1 hour. MAIN OUTCOME MEASURES: Total blood loss, mean arterial pressure, ballistic injury, and mortality were recorded after 1 hour. RESULTS: The injuries were equivalent for the 2 groups. No animal mortality was seen. After 1 hour, the mean (+/-SEM) blood loss was 124+/-64 mL in the DFSD-treated group and 377+/-64 mL in the gauze dressings-treated group (P=.01). Twenty minutes after injury, the mean arterial pressure was 95.0 mm Hg (+/-SEM, +/-4.7 mm Hg) in the DFSD-treated group and 70.0+/-5.0 mm Hg in the gauze dressings-treated group. The difference persisted for the remainder of the study (P=.01). CONCLUSION: The DFSD was superior to gauze in decreasing blood loss and maintaining blood pressure while retaining the simplicity of standard dressing application.
Animals↗
Molecular genetics of the germinal center reaction.
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Animals↗