Urinary and blood manganese in occupationally nonexposed populations and in manual metal are welders of mild steel

Summary To obtain reference values for blood and serum manganese levels, blood specimens were collected from 29 men and 36 women. Mn in blood showed a normal distribution; its upper 97.5% limit in blood was 0.38 mol/l. Mn in serum showed a skewed distribution, which did not differ from the normal one after logarithmic transformation. The respective reference limit was 19 nmol/l. In both specimens, the levels of Mn were significantly lower in men than in women. To obtain reference values for Mn in urine, midday urine specimens were collected from 58 men and 96 women. Mn in urine also showed a skewed distribution, and the upper 97.5% limit was 38 nmol/l. The levels of Mn in blood and urine were statistically significantly higher in manual metal arc (MMA) welders of mild steel (MS) than in the reference populations. Five MMA/MS welders were subjected to a further study in which the ambient intramask Mn levels and urinary Mn excretion were monitored throughout a full working week. For two welders the correlation of Mn in urine specimens voided in the afternoon was good with the before noon Mn concentrations in the hygienic measurements; for the rest the correlation was minimal. Mn in diurnal urine specimens collected in six portions showed fluctuation if specific gravity or creatinine in urine was used to standardize for the urinary flow, but it was less evident for urinary Mn excretion rate. Our results seem to indicate that the measurement of Mn in urine or blood may be used for monitoring Mn exposure in MMA/MS welders only at the group level.These results were presented in part at the 2nd COMTOX meeting, held in Montreal in 1983     

Flotillin-1 (Reggie-2) contributes to Chlamydia pneumoniae growth and is associated with bacterial inclusion

Chlamydiae are obligate intracellular pathogens replicating only inside the eukaryotic host. Here, we studied the effect of human flotillin-1 protein on Chlamydia pneumoniae growth in human line (HL) and A549 epithelial cell lines. RNA interference was applied to disrupt flotillin-1-mediated endocytosis. Host-associated bacteria were detected by quantitative PCR, and C. pneumoniae growth was evaluated by inclusion counts. C. pneumoniae attachment to host cells was unaffected, but bacterial intracellular growth was attenuated in the flotillin-1-silenced cells. By using confocal microscopy, we detected flotillin-1 colocalized with the inclusion membrane protein A (IncA) in the C. pneumoniae inclusion membranes. In addition, flotillin-1 was associated with IncA in detergent-resistant membrane microdomains (DRMs) in biochemical fractioning. These results suggest that flotillin-1 localizes to the C. pneumoniae inclusion membrane and plays an important role for intracellular growth of C. pneumoniae.     

Gene therapy for the induction of chimerism and transplant tolerance

Technical advances in transplant surgery and the development of powerful and effective immunosuppressive drugs have contributed to the success of organ transplantation as a medical treatment for patients with end-stage diseases. Associated with this procedure, however, is a dependence on life-long immunosuppressive drugs, which are required to prevent graft rejection. These agents render the patient susceptible to infections, tumors and various side affects. The ability to achieve tolerance to organ grafts would free transplant patients from lifelong dependency on pharmacological agents with harmful side effects. Several laboratories have shown that tolerance can be achieved by the induction of mixed cell chimerism and/or by molecular chimerism achieved by gene transfer techniques prior to graft placement. Molecular chimerism, induced by transplantation of autologous bone marrow expressing either allo- or xenoantigens has the potential to induce tolerance without the development of graft vs. host disease. The application of gene transfer techniques to induce chimerism has been shown to reshape the immune repertoire by mechanisms that include clonal deletion, the induction of central tolerance or generation of regulatory T cells that would eliminate the need for immunosuppressive drugs. Optimization of this methodology for clinical use could therefore revolutionize the field of transplantation. This review summarizes the recent studies which have compared the efficacy of different vectors, conditioning regimens, and transduction conditions leading to new and improved techniques for the application of gene therapy to induce chimerism and transplant tolerance to both allografts and xenografts.     

Production of Chlamydia pneumoniae Proteins in Bacillus subtilis and Their Use in Characterizing Immune Responses in the Experimental Infection Model

Due to intracellular growth requirements, large-scale cultures of chlamydiae and purification of its proteins are difficult and laborious. To overcome these problems we produced chlamydial proteins in a heterologous host, Bacillus subtilis, a gram-positive nonpathogenic bacterium. The genes of Chlamydia pneumoniae major outer membrane protein (MOMP), the cysteine-rich outer membrane protein (Omp2), and the heat shock protein (Hsp60) were amplified by PCR, and the PCR products were cloned into expression vectors containing a promoter, a ribosome binding site, and a truncated signal sequence of the α-amylase gene from Bacillus amyloliquefaciens. C. pneumoniae genes were readily expressed in B. subtilis under the control of the α-amylase promoter. The recombinant proteins MOMP and Hsp60 were purified from the bacterial lysate with the aid of the carboxy-terminal histidine hexamer tag by affinity chromatography. The Omp2 was separated as an insoluble fraction after 8 M urea treatment. The purified proteins were successfully used as immunogens and as antigens in serological assays and in a lymphoproliferation test. The Omp2 and Hsp60 antigens were readily recognized by the antibodies appearing after pulmonary infection following intranasal inoculation of C. pneumoniae in mice. Also, splenocytes collected from mice immunized with MOMP or Hsp60 proteins proliferated in response to in vitro stimulation with the corresponding proteins.     

18q deletions: clinical, molecular, and brain MRI findings of 14 individuals

We studied 14 individuals with partial deletions of the long arm of chromosome 18, including terminal and interstitial de novo and inherited deletions. Study participants were examined clinically and by brain MRI. The size of the deletion was determined by segregation analysis using microsatellite markers. We observed that the phenotype was highly variable, even in two families with three 1st degree relatives. Among the 14 individuals, general intelligence varied from normal to severe mental retardation. The more common features of 18q-deletions (e.g., foot deformities, aural atresia, palatal abnormalities, dysmyelination, and nystagmus) were present in individuals lacking only the distal portion 18q22.3-qtel. Interstitial deletions exerted very heterogeneous effects on phenotype. In individuals with distal 18q22.3-q23 deletions, brain MRI was very distinctive with poor differentiation of gray and white matter on T2-weighted images.     

Real-world evidence data on the monoclonal antibody erenumab in migraine prevention: perspectives of treating physicians in Germany

BackgroundErenumab, the first-in-class fully human monoclonal antibody targeting the calcitonin gene-related peptide receptor, was shown to be efficacious and safe for the prophylactic treatment of migraine in adults in randomized clinical trials. Large-scale, real-world evidence in multi-centre settings is still needed to confirm these results. Erenumab patient profiles outside clinical trials and physicians’ treatment patterns, as well as data from patients treated in Germany, a severely impacted population, are not published yet.MethodsTELESCOPE was a multi-centre survey gathering real-world data from 45 German headache centres between July 2019 and December 2019. The project consisted of two parts. In the first part, treating physicians shared their experiences on current erenumab treatment with regard to patient profiles, treatment patterns and treatment responses. In the second part, a retrospective chart review was conducted of 542 migraine patients treated with erenumab for at least three months. Treatment responses focused on various aspects of patients’ quality of life.ResultsThe analysis of 542 patients’ charts revealed that three-month treatment with erenumab significantly reduced monthly headaches, migraine and acute medication days. Furthermore, headache intensity and frequency were reduced in over 75 % and accompanying aura in 35 % of patients. The clinical global impression scale revealed a general improvement in 91 % of patients. According to the treating physicians’ professional judgement, 83 % of patients responded to erenumab and 80 % were satisfied with the treatment. Physicians evaluated restricted quality of life, the number of monthly migraine days and previous, prophylactic treatments as the main components of the current patient profile for monoclonal antibody recipients. Based on the assessment of physicians, erenumab reduced migraine symptoms in 65 % and increased quality of life in more than 75 % of their patients.ConclusionsTELESCOPE confirms positive treatment responses with erenumab shown in clinical trials in a real-world multi-centre setting. The results show consistently positive experiences of physicians utilizing erenumab in clinical practice and underline that therapy with this monoclonal antibody is effective in migraine patients, particular in those, who have failed several prophylactic therapies.     

Patient Preferences for Treatment of Low Back Pain—A Discrete Choice Experiment

BackgroundBack pain imposes a substantial economic and social burden, and treatment decisions are distorted by conflicting evidence. Thus, it is important to include patient preferences in decision making and policy making.ObjectiveTo contribute to the understanding of patient preferences in relation to the choice of treatment for low back pain.MethodsA discrete choice experiment was conducted with consecutive patients referred to a regional spine center. The respondents (n = 348) were invited to respond to a choice of two hypothetical treatment options and an opt-out option. The treatment attributes included the treatment modality, the risk of relapse, the reduction in pain, and the expected increase in the ability to perform activities of daily living. In addition, the wait time to achieve the treatment effect was used as a payment vehicle. Mixed logit models were created to perform analysis. Subgroup analysis, dividing respondents into sociodemographic and disease-related categories, further explored the willingness to wait.ResultsRespondents assigned positive utilities to positive treatment outcomes and disutility to higher risks and longer waits for effects of treatment and to surgical interventions. The model captured significant heterogeneity within the sample for the outcomes of pain reduction and the ability to pursue activities of daily living and for the treatment modality. The subgroup analysis revealed differences in the willingness to wait, especially with regard to treatment modality, the level of pain experienced at the time of data collection, and the respondents’ preferences for surgery.ConclusionsThe majority of the respondents prefer nonsurgical interventions, but patients are willing to wait for more ideal outcomes and preferred interventions. The results show that health care professionals have a very important task in communicating clearly about the expected results of treatment and the basis of their treatment decisions, as patients' preferences are highly individual.     

Cell-to-cell contact of human monocytes with infected arterial smooth-muscle cells enhances growth of Chlamydia pneumoniae

Chlamydia pneumoniae can infect arterial cells. It has been shown that coculture of human monocytes (U937) and endothelial cells promotes infection of C. pneumoniae in endothelial cells and that the enhancement was mediated by a soluble factor (insulin-like growth factor 2) secreted by monocytes. In this study, it is shown that coculture of monocytes with C. pneumoniae enhances infection of C. pneumoniae in arterial smooth-muscle cells 5.3-fold at a monocyte-to-smooth-muscle cell ratio of 5. However, unlike endothelial cells, no enhancement was observed if monocytes were placed in cell culture inserts or if conditioned medium from monocyte cultures was used, which suggests that cell-to-cell contact is critical. The addition of mannose 6-phosphate or octyl glucoside, a nonionic detergent containing a sugar group, to cocultures inhibited the enhancement. These findings suggest that the monocyte-smooth-muscle cell interaction may be mediated by mannose 6-phosphate receptors present on monocytes.