[Gene therapy of X-linked severe combined immunologic deficiency (SCID-X1)]

X-linked severe combined immunodeficiency (SCID-X1) is a recessive hereditary disorder in which early T and Natural Killer (NK) lymphocyte development is blocked. The genetic disorder results from mutations in the common gamma c chain that participates in several cytokine receptors including the interleukin-2 (Il-2), Il-4, Il-7, Il-9, Il-15 receptors. SCID-X1 offers a reliable model for gene therapy as it is a lethal condition that is, in many cases, curable by allogeneic bone marrow transplantation. We have shown that retrovirus-mediated transfer of the gamma c cDNA induced gamma c chain expression and restored the function of the high-affinity IL-2 receptor on SCI-X1 EBV-transformed B-cell lines. We have the designed culture conditions to study NK-cell and T-cell development of CD34+ hematopoietic progenitor cells. In the culture systems, gamma c transduced CD34+ marrow cells from two SCID-X1 patients were able to mature into CD56+ and/or CD16+ NK cells and into CD4+ TCR alpha beta+ T cells. These preclinical results set the basis for a clinical study of ex-vivo gamma c gene transfer into CD34+ cells from SCID-X1 patients.

Localization of the peptide transporter PEPT2 in the lung: implications for pulmonary oligopeptide uptake

Pulmonary delivery of peptidomimetic antibiotics is frequently used for local drug therapy in pulmonary infections. Identification of transport pathways into airway epithelia can lead to new strategies of therapy. Here we describe the distribution of the beta-lactam-transporting high-affinity proton-coupled peptide transporter PEPT2 in mammalian lungs. Using reverse transcriptase-polymerase chain reaction and Northern blot analysis, PEPT2-mRNA was detected in lung extracts. The expression of PEPT2-mRNA and protein was localized to alveolar type II pneumocytes, bronchial epithelium, and endothelium of small arteries of rat lung by nonisotopic in situ hybridization and immunohistochemistry. In addition, transport studies using murine whole-organ preparations revealed transporter-mediated uptake of a fluorophore-conjugated dipeptide derivative into bronchial epithelial cells and type II pneumocytes. This transport was competitively inhibited by cephalosporins and dipeptides that are reported as PEPT2-carried substrates. Cell specificity of the PEPT2-mediated uptake pattern was confirmed by double labeling with Lycopersicon esculentum lectin. Together these data suggest that PEPT2 is the molecular basis for the transport of peptides and peptidomimetics in pulmonary epithelial cells. In conclusion PEPT2 may be an interesting target for pulmonary delivery of peptides and peptidomimetics.

CD40-CD40L independent Ig gene hypermutation suggests a second B cell diversification pathway in humans

Somatically mutated IgM(+)-only and IgM(+)IgD(+)CD27(+) B lymphocytes comprise approximately 25% of the human peripheral B cell pool. These cells phenotypically resemble class-switched B cells and have therefore been classified as postgerminal center memory B cells. X-linked hyper IgM patients have a genetic defect characterized by a mutation of the CD40L gene. These patients, who do not express a functional CD40 ligand, cannot switch Ig isotypes and do not form germinal centers and memory B cells. We report here that an IgM(+)IgD(+)CD27(+) B cell subset with somatically mutated Ig receptors is generated in these patients, implying that these cells expand and diversify their Ig receptors in the absence of classical cognate T-B collaboration. The presence of this sole subset in the absence of IgM(+)-only and switched CD27(+) memory B cells suggests that it belongs to a separate diversification pathway.

Factors V leiden and II 20210A in patients with symptomatic pulmonary embolism and deep vein thrombosis

PURPOSE

Factor V Leiden and factor II 20210A are inherited disorders of the clotting system that occur frequently in patients with deep vein thrombosis. We conducted this study to determine whether these factors are also common in patients with pulmonary embolism.

SUBJECTS AND METHODS

We determined the prevalence of factor V Leiden and factor II 20210A in 773 consecutive patients with objectively documented symptomatic deep vein thrombosis or symptomatic pulmonary embolism, or with a combination of these disorders.

RESULTS

Isolated symptomatic deep vein thrombosis occurred in 345 patients; isolated symptomatic pulmonary embolism occurred in 236; and both anomalies occurred in 192. Factor V Leiden was present in 21 (9%) of the patients with isolated symptomatic pulmonary embolism, in 30 (16%) with both manifestations, and in 63 (18%) with isolated symptomatic deep vein thrombosis (P = 0.007). Factor V Leiden was more common among patients with deep vein thrombosis (odds ratio [OR] = 2.1; 95% confidence interval [CI]: 1.2 to 3.7; P = 0.006) or both pulmonary embolism and deep vein thrombosis (OR = 1.8; 95% CI: 1.0 to 3.3; P = 0.07) than among patients with isolated pulmonary embolism. Factor V Leiden was less common in massive pulmonary embolism (5% [7 of 127]) than in submassive pulmonary embolism (13% [21 of 155], P = 0.03). We found no significant difference in the prevalence of factor II 20210A among the three groups.

CONCLUSION

Factors V Leiden and II 20210A vary in prevalence among patients with pulmonary embolism and deep vein thrombosis, suggesting that the risk of pulmonary embolization may vary among patients who have different causes of venous thromboses.

The interaction between Cdc42 and WASP is required for SDF-1-induced T-lymphocyte chemotaxis

In studies aimed at further characterizing the cellular immunodeficiency of the Wiskott-Aldrich syndrome (WAS), we found that T lymphocytes from WAS patients display abnormal chemotaxis in response to the T-cell chemoattractant stromal cell-derived factor (SDF)-1. The Wiskott- Aldrich syndrome protein (WASP), together with the Rho family GTPase Cdc42, control stimulus-induced actin cytoskeleton rearrangements that are involved in cell motility. Because WASP is an effector of Cdc42, we further studied how Cdc42 and WASP are involved in SDF-1-induced chemotaxis of T lymphocytes. We provide here direct evidence that SDF-1 activates Cdc42. We then specifically investigated the role of the interaction between Cdc42 and WASP in SDF-1-responsive cells. This was achieved by abrogating this interaction with a recombinant polypeptide (TAT-CRIB), comprising the Cdc42/Rac interactive binding (CRIB) domain of WASP and a human immunodeficiency virus-TAT peptide that renders the fusion protein cell-permeant. This TAT-CRIB protein was shown to bind specifically to Cdc42-GTP and to inhibit the chemotactic response of a T-cell line to SDF-1. Altogether, these data demonstrate that Cdc42-WASP interaction is critical for SDF-1-induced chemotaxis of T cells.

Endogenous opioids as mediators of asthma

Changes in airway innervation are believed to play a key role in the pathophysiology of asthma. A group of regulatory peptides which act as neuroregulators is resembled by the opioids. Their localization to neurons projecting into airways suggested a possible role as regulators of neurogenic inflammation, bronchoconstriction and mucus secretion. They mainly act through modification of tachykinergic and cholinergic impulses and their ability to inhibit bronchoconstriction prompted discussion of their potential value in asthma therapy. Apart from the presence of the classical opioids and their receptors in the lung and their functional role, a new group of peptides such as nociceptin and endomorphins have been characterized in the airways. Whereas at least endomorphin-1 acts via the classical OP(3) (mu) receptor, nociceptin binds to a new receptor termed opioid receptor-like-receptor (ORL(1)) and inhibits tachykinergic constriction. Contrary to these promising modulatory effects on airway smooth muscle tone, effective therapeutic strategies have not been developed yet. In conclusion, opioids resemble a group of regulatory peptides which are present within airway-innervating nerve fibres and influence a multitude of airway functions via modification of neural transmission.

Zinc inhibits the mixed lymphocyte culture

The mixed lymphocyte culture (MLC) is an established clinical method for bone marrow transplantation, as it serves as an in vitro model for allogenic reaction and transplantation. We previously showed that cytokine release into the supernatant is a more specific and sensitive parameter for cross-reactivity in the MLC than the common measurement of cell proliferation. Therefore we tried to find an inhibitor of the MLC in vitro with the least side effects in vivo, measuring interferon (IFN)-gamma as one of the most important cytokines in posttransplant medicine. Earlier studies showed that zinc is an important trace element for immune function with both stimulatory and inhibitory effects on immune cells. We found that slightly elevated zinc concentrations (three to four times the physiological level), which do not decrease T-cell proliferation in vitro nor produce immunosuppressive effects in vivo, suppress alloreactivity in the mixed lymphocyte culture. In this report we analyzed the mechanism whereby zinc influences the MLC to possibly find a nontoxic way of immunosuppression.

Changes in height, weight and plasma leptin after bone marrow transplantation

Short stature can be a severe side-effect of bone marrow transplantation (BMT). Because of the effect of weight changes on growth rate and on plasma insulin-like growth factor (IGF I), we analyzed changes in height and body mass index (BMI) in 53 patients given BMT. Group 1 (n = 22) was given 12 Gy total body irradiation (TBI) as six fractions, group 2 (n = 14) 10 Gy TBI (one dose), group 3 (n = 8) 6 Gy total lymphoid irradiation (one dose), and group 4 (n = 9) chemotherapy alone. At the first evaluation, 13/36 patients in groups 1 and 2 had low growth hormone (GH) peaks after stimulation. The mean plasma IGF I concentrations (z score) were similar in groups 1 (-2.9 +/- 0.3) and 2 (-2.5 +/- 0.3), and in groups 3 (-1.4 +/- 0.3) and 4 (-1.4 +/- 0.7), but those of group 1 were lower than those of groups 3 (P < 0.01) and 4 (P < 0.05), and those of group 2 than those of group 3 (P < 0.05). BMI during the 5 years after BMT did not change in groups 1 and 2, decreased in group 3, and increased in group 4. However, these changes were not significant. Most of the patients given TBI had BMI below the mean at 2 (66%) and 5 (57%) years later. Their BMI and leptin concentrations correlated positively with each other (P = 0.005), and negatively with GH peak (P = 0.02 for BMI and 0.007 for leptin). In conclusion, this study suggests that TBI actually decreases GH secretion and is followed by a persistent low BMI. The negative relationship between GH peak and leptin may indicate that both are markers of a TBI-induced hypothalamic-pituitary lesion.

[Perceptions of nursing service managers in the South African Military Health Service on their level of motivation]

The process of transformation in the South African Military Health Services, has influenced the nursing service managers' level of motivation and the following research question is applicable: what are the perceptions of the nursing service managers within the South African Military Health Services on their level of motivation? The purpose with this study was to explore and describe the perceptions of nursing service managers on their level of motivation within these health services. A qualitative research design was utilized and four focus group interviews were conducted with 33 nursing service managers country wide. The transcribed interviews were exposed to a content analysis. The results confirm that the level of motivation amongst these nursing service managers is low. The demotivators relate mainly to the following: inadequate acknowledgement, job insecurity in relation to the future, problems with the process of integration, transformation and rationalization, problems with management, many labour related issues, poor/inadequate communication, inadequate support, increased work load, poor physical environment, negative publicity and poor self motivation. Although there were a few motivators identified, they were of less importance. These results were interpreted within Herzberg's motivation theory to identify the hygiene/maintenance factors and to assess whether the important motivators were in place. During any process of change, and/or when the level of motivation amongst employees is low, it is important to adequately manage the environment (hygiene/maintenance factors within the Herzberg theory). But it is even more important to ensure that the motivators are in place or to intensify them. It is therefore recommended that a motivation strategy, based on the Herzberg theory as well as the Hackman-Oldham job enrichment model, be developed, implemented and evaluated.

Gene therapy of lymphoid primary immunodeficiencies

Gene therapy offers an attractive option to the most severe forms of primary immunodeficiency diseases. Identification of disease-associated genes as well as advances in the technology of gene transfer into hematopoietic progenitor cells have set the basis for the first clinical trials. Settings characterized by the potential for a selective advantage provided to transduced cells are the first diseases to target. The recent example of successful treatment of severe combined immunodeficiency-X1 (gammac deficiency) illustrates this potential.

Mutations in activation-induced cytidine deaminase in patients with hyper IgM syndrome

Recent studies have shown that mutations in a newly described RNA editing enzyme, activation-induced cytidine deaminase (AID), can cause an autosomal recessive form of hyper IgM syndrome. To determine the relative frequency of mutations in AID, we evaluated a group of 27 patients with hyper IgM syndrome who did not have defects in CD40 ligand and 23 patients with common variable immunodeficiency. Three different mutations in AID were identified in 18 patients with hyper IgM syndrome, including 14 French Canadians, 2 Lumbee Indians, and a brother and sister from Okinawa. No mutations were found in the remaining 32 patients. In the group of patients with hyper IgM syndrome, the patients with mutations in AID were older at the age of diagnosis, were more likely to have positive isohemagglutinins, and were less likely to have anemia, neutropenia, or thrombocytopenia. Lymphoid hyperplasia was seen in patients with hyper IgM syndrome and normal AID as well as the patients with hyper IgM syndrome and defects in AID.

Gene therapy of severe combined immunodeficiencies

Primary immunodeficiency diseases (PID) are attractive candi dates for a gene therapy approach because many of these disorders convey a poor prognosis while a number of the genes mutated in these conditions have been identified. Gene transfer into hematopoietic stem cells (HSC) should, in theory, lead to a cure of the disease. There are, however, a number of limitations mostly related to the failure of clinically available vectors to enable transgene integration into HSC. Nevertheless PID due to a gene defect leading to failure of cell development could be amenable to gene therapy given the selective advantage conferred to transgene expression in progenitor cells. Terminally differentiated cells are, however, long lived, as is the case for T lymphocytes. This concept led to the first gene therapy trials for adenosine deaminase (ADA) deficiency several years ago. Results were in part disappointing mostly because of the concomitant substitutive treatment by polyethylene glycol-ADA. However, recent application to X-linked severe combined immunodeficiency (gamma(c) deficiency) turned out to be efficient at least on a relatively short term basis (i.e. one year so far). These results demonstrate that this concept is valid and can be the basis for the treatment of other forms of severe T-cell immunodeficiencies. Obviously, development of vectors (lentiviruses) able to efficiently target HSC could in the future considerably enlarge the field of PID treatable by gene transfer.

Boxing and running lead to a rise in serum levels of S-100B protein

Permanent neurological dysfunction is the primary medical concern of boxing. Recently it was reported that patients presenting elevated levels of the glial protein S-100B in serum after minor head injuries are more prone to develop neuropsychological deficits than patients with lower levels of S-100B protein. We assessed this protein before and after amateur boxing competitions (n = 10) and sparring bouts (n = 15). In several control groups, we investigated S-100B levels of participants before and after a 25 km race (n = 11), jogging (10 km, n = 12), short-term running (n = 12), and heading footballs (n = 12). There was an increase in S-100B protein after boxing and the running disciplines but not after ergometer cycling or soft heading of footballs. The increase in S-100B protein concentrations due to competitive boxing and after the 25 km race was significantly higher than that after performing other disciplines (p < 0.001). There was no significant difference between the increases caused by sparring and the running disciplines (p = 0.21). The number and severity of the strikes to the head correlated significantly with the increase in the S-100B protein levels. Levels of S-100B protein known to be associated with neuropsychological deficits were not reached in our study. In professional boxing, much higher levels are to be expected and would be worthy of investigation.

Oscillating expression of c-Hey2 in the presomitic mesoderm suggests that the segmentation clock may use combinatorial signaling through multiple interacting bHLH factors

Vertebrate somitogenesis comprises the generation of a temporal periodicity, the establishment of anteroposterior compartment identity, and the translation of the temporal periodicity into the metameric pattern of somites. Molecular players at each of these steps are beginning to be identified. Especially, members of the Notch signaling cascade appear to be involved in setting up the somitogenesis clock and subsequent events. We had previously demonstrated specific expression of the mHey1 and mHey2 basic helix-loop-helix (bHLH) factors during somitogenesis. Here we show that perturbed Notch signaling in Dll1 and Notch1 knockout mutants affects this expression in the presomitic mesoderm (PSM) and the somites. In the caudal PSM, however, mHey2 expression is maintained and thus is likely to be independent of Notch signaling. Furthermore, we analysed the dynamic expression of the respective chicken c-Hey1 and c-Hey2 genes during somitogenesis. Not only is c-Hey2 rhythmically expressed across the chicken presomitic mesoderm like c-hairy1, but its transcription is similarly independent of de novo protein synthesis. In contrast, the dynamic expression of c-Hey1 is restricted to the anterior segmental plate. Both c-Hey genes are coexpressed with c-hairy1 in the posterior somite half. Further in vitro and in vivo interaction assays demonstrated direct homo- and heterodimerisation between these hairy-related bHLH proteins, suggesting a combinatorial action in both the generation of a temporal periodicity and the anterior-posterior somite compartmentalisation.

[Schizophrenic psychoses and suicide in the clinic. Risk factors, psychopharmacologic treatment]

For all 5,352 patients treated for schizophrenia at the Psychiatric Hospital of the University of Munich in 1981 and 1992, detailed routine and data processing-assisted documentations were made of the psychopharmacological therapies. Nineteen of the patients committed suicide while undergoing inpatient treatment; the control group consisted of all other patients (n = 5,333). More than 77 sociodemographic and anamnestic variables as well as 195 items from the admission summaries were taken into account while comparing the groups. Furthermore, the pharmacological data were classified according to drug groups and comparison was based on the mean frequency of prescription of each group. We analyzed the mean number of prescriptions for neuroleptics, tranquilizers, and antidepressants, which were further differentiated into sedating and nonsedating types. For frequently administered drugs, mean daily doses were also compared. Bivariate analysis of the data suggests that the suicide cases presented depressive signs, symptoms, and tendencies already present on admission more frequently than with controls; the same applies to previously attempted suicides. Discriminating analysis showed that the variables "feeling of loss of feelings," thought insertion," "visible depression," "free-floating anxiety," "suicidal tendencies," and "previously attempted suicide" have the greatest predictive value with respect to suicide, in descending order. No differences in psychopharmacological treatment between suicides and controls were found, apart from a significantly higher percentage of antidepressive treatments and a higher mean number of antidepressant prescriptions for the suicides.

Expression of heme oxygenase isoenzymes 1 and 2 in normal and asthmatic airways: effect of inhaled corticosteroids

Heme oxygenase (HO) is considered to be an antioxidant enzyme that catabolizes heme to produce carbon monoxide (CO) and biliverdin. We determined the expression and distribution of HO-1 and HO-2, two isoenzymes of HO, in the airways of patients with asthma, and determined the effect of inhaled corticosteroid therapy. Immunostaining for both enzymes was widely distributed in the airways' submucosa, particularly in airway epithelium and submucosal macrophages (CD68(+)) as determined by double immunostaining. There was no difference in intensity and extent of staining in biopsies from normal subjects (n = 10) and subjects with asthma (n = 10). Following 1 mo of treatment with inhaled corticosteroids (budesonide 1,600 microg/d), there was no significant change in the expression and distribution of either HO-1 or HO-2 in the airways' submucosa in eight subjects with mild asthma, despite a significant reduction in airway eosinophils and a reduction in bronchial responsiveness to methacholine. Levels of exhaled nitric oxide were significantly reduced, but exhaled CO levels remained unchanged by the treatment. Treatment with a placebo inhaler (n = 8) had no effects on these parameters. Thus, both HO-1 and HO-2 are extensively distributed equally in normal subjects and subjects with asthma, and are not modulated by inhaled corticosteroid therapy in subjects with asthma. HO may be an important endogenous antioxidant enzyme.

Phenylacetylene as a new surrogate standard for the determination of BTEX by GC/FID

Benzene, toluene, ethylbenzene, xylene (short form: BTEX) and other monoaromatic compounds are environmental contaminants which are often analyzed by GC/FID. For the calculation of BTEX concentrations in water samples normally external quantification with defined BTEX solutions is sufficient. However, for accurate quantification of BTEX in complex matrices it is necessary to use internal standards, e.g. 1-chlorohexane. Isotopes of BTEX are usually the best alternative but they are only applicable to GC/MS, because their retention times are similar to the original BTEX. 1-Chlorohexane and phenylacetylene were compared with respect to their quality as internal standards. Good results were obtained with the monoaromatic phenylacetylene as a surrogate standard. The physical properties of phenylacetylene are very similar to BTEX species and it normally does not occur in environmental samples. 1-Chlorohexane was more strongly adsorbed on the used soil than BTEX during sample preparation. This fact suggests that the single aromatic rings of BTEX and phenylacetylene are mainly responsible for the adsorption behavior.

Die verpleegdiensbestuurders binne die Suid-Afrikaanse Militêre gesondheidsdiens se persepsies oor hul vlak van motivering

The process of transformation in the South African MilitaryHealth Services, has influenced the nursing servicemanagers’ level of motivation and the following researchquestion is applicable: what are the perceptions of thenursing service managers within the South African MilitaryHealth Services on their level of motivation? The purpose with this study was to explore and describe theperceptions of nursing service managers on their level ofmotivation within these health services. A qualitative researchdesign was utilized and four focus group interviewswere conducted with 33 nursing service managers countrywide. The transcribed interviews were exposed to acontent analysis. The results confirm that the level ofmotivation amongst these nursing service managers is low.The demotivators relate mainly to the following: inadequateacknowledgement, job insecurity in relation to thefuture, problems with the process of integration, transformationand rationalization, problems with management,many labour related issues, poor/inadequate communication,inadequate support, increased work load, poor physicalenvironment, negative publicity and poor self motivation.Although there were a few motivators identified,they were of less importance. These results were interpretedwithin Herzberg’s motivation theory to identify thehygiene/maintenance factors and to assess whether theimportant motivators were in place. During any processof change, and/or when the level of motivation amongstemployees is low, it is important to adequately managethe environment (hygiene/maintenance factors within theHerzberg theory). But it is even more important to ensurethat the motivators are in place or to intensify them. It istherefore recommended that a motivation strategy, basedon the Herzberg theory as well as the Hackman-Oldhamjob enrichment model, be developed, implemented andevaluated.