Preparation of unnatural N-to-N and C-to-C protein fusions

Standard genetic approaches allow the production of protein composites by fusion of polypeptides in head-to-tail fashion. Some applications would benefit from constructions that are genetically impossible, such as the site-specific linkage of proteins via their N or C termini, when a remaining free terminus is required for biological activity. We developed a method for the production of N-to-N and C-to-C dimers, with full retention of the biological activity of both fusion partners and without inflicting chemical damage on the proteins to be joined. We use sortase A to install on the N or C terminus of proteins of interest the requisite modifications to execute a strain-promoted copper-free cycloaddition and show that the ensuing ligation proceeds efficiently. Applied here to protein-protein fusions, the method reported can be extended to connecting proteins with any entity of interest.     

The EBMT activity survey: 1990-2010

A total of 654 centers from 48 countries were contacted for the 2010 survey. In all, 634 centers reported a total of 33?362 hematopoietic SCT (HSCT) with 30?012 patients receiving their first transplant (12?276 allogeneic (41%) and 17?736 autologous (59%)). Main indications were leukemias: 9355 (31%; 93% allogeneic), lymphoid neoplasias specifically Non Hodgkin's lymphoma, Hodgkin's lymphoma and plasma cell disorders: 17?362 (58%; 12% allogeneic), solid tumors: 1585 (5%; 6% allogeneic) and non-malignant disorders: 1609 (6%; 88% allogeneic). There were more unrelated donors than HLA-identical sibling donors (53% versus 41%); the proportion of peripheral blood as stem cell source was 99% for autologous and 71% for allogeneic HSCT. Cord blood was primarily used in allogeneic transplants (6% of total) with three autologous cord blood HSCT being reported. The number of transplants has increased by 19% since 2005 (allogeneic 37% and autologous 9%) and continued to increase by about 1100 HSCT per year since 2000. Patterns of increase were distinct and different. The data show the development of transplantation in Europe since 1990, with the number of patients receiving a HSCT increasing from 4200 to over 30?000 annually. The most impressive trend seen is the steady increase of unrelated donor transplantation, in parallel to the availability of unrelated donors through donor registries.     

Clinical markers of early nigrostriatal neurodegeneration in idiopathic rapid eye movement sleep behavior disorder

Background

Rapid eye movement sleep behavior disorder (RBD) is an early feature in α synucleinopathies and may precede other clinical manifestations of disease for several years. Olfactory dysfunction and mild motor abnormalities (MMAs) are highly prevalent in prodromal α synucleinopathies such as RBD and are suspected to be predictive neurodegenerative markers. Because both markers also are highly prevalent in the healthy elderly population, the discriminative value to detect an early neurodegenerative process is unclear.

Methods

We examined 28 patients with idiopathic RBD (iRBD) without manifest neurodegenerative disease to determine diagnostic accuracy of MMAs and olfactory dysfunction in identifying patients with early nigrostriatal degeneration in transcranial sonography (TCS) and ¹²³I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane single-photon emission computed tomography (¹²³I-FP-CIT-SPECT).

Results

Sixty-three percent of our participants showed MMAs which were strongly associated with abnormal TCS and ¹²³I-FP-CIT-SPECT findings. The discriminative value in detecting participants with early nigrostriatal degeneration was excellent (area under the receiver operating characteristic [ROC] curve, 0.84 [P ? .003] for TCS and 0.79 [P ? .066] for ¹²³I-FP-CIT-SPECT). Olfactory dysfunction was present in 78% of iRBD participants, but it was not linked with neuroimaging abnormalities or MMAs. Olfactory dysfunction did not discriminate participants with early nigrostriatal degeneration (area under the ROC curve, 0.54 [P ? .747] for TCS and 0.31 [P ? .225] for ¹²³I-FP-CIT-SPECT). Early RBD manifestation but no demographic (e.g., age, gender) or clinical characteristics of RBD (e.g., duration, severity of RBD) were associated with neuroimaging abnormalities in TCS and ¹²³I-FP-CIT-SPECT.

Conclusions

Unlike olfactory dysfunction, MMAs discriminate patients with early nigrostriatal degeneration in iRBD. Early RBD manifestation seems to be an additional risk factor which aggravates neurodegenerative risk.     

In vitro and in vivo evaluation of biodegradable,open-porous scaffolds made of sintered magnesium W4 short fibres

A cytocompatible and biocompatible, degradable, open-porous, mechanically adaptable metal scaffold made of magnesium alloy W4 melt-extracted short fibres was fabricated by liquid phase sintering. Cylindrical samples (3 × 5 mm) of sintered W4 short fibres were evaluated under in vitro (L929, HOB, eudiometer, weight loss) and in vivo conditions (rabbits: 6 and 12 weeks). The in vitro corrosion environment (e.g., temperature, flow, composition of corrosion solution, exposure time) significantly influenced the corrosion rates of W4 scaffolds compared with corrosion in vivo. Corrosion rates under cell culture conditions for 72 h varied from 1.05 to 3.43 mm y^?1 depending on the media composition. Corrosion rates measured in eudiometric systems for 24 h were ～24–27 times higher (3.88–4.43 mm y^?1) than corrosion in vivo after 6 weeks (0.16 mm y^?1). Moreover, it was found that the cell culture media composition significantly influences the ionic composition of the extract by selectively dissolving ions from W4 samples or their corrosion products. A pilot in vivo study for 6 and 12 weeks demonstrated active bone remodelling, no foreign body reaction and no clinical observation of gas formation during W4 scaffold implantation. Long-term in vivo studies need to be conducted to prove complete degradation of the W4 scaffold and total replacement by the host tissue.     

Relationship between multimorbidity and direct healthcare costs in an advanced elderly population

Objectives

The goal of this work was to analyze the impact of the extent of multimorbidity on health service resource utilization and, thus, direct healthcare costs of advanced elderly in the German population.

Methods

Based on a cross-sectional sample aged 72 or above in Germany (n?=?1,937), a bottom-up study assessing resource utilization and corresponding costs was performed. Main data sources were patient-reported information concerning morbidity and health service resource utilization administered via telephone interviews within the framework of the PRISCUS trial. To value resource utilization, unit costs were determined for all services under consideration. In order to estimate the impact of multimorbidity on mean annual direct costs, a cumulative multimorbidity index was constructed. Influencing factors on annual average costs were identified via multivariate linear regression models.

Results

Mean annual direct costs of 3,315?EUR (95%?confidence interval (CI) 3,118; 3,512) at 2010 prices were caused by the involved patients: 25% of mean annual costs were due to inpatient care, 20% to outpatient physician services, 20% to pharmaceuticals, 12% to assisted living and transportation, 8% to healthcare products and dentures, 7% to rehabilitation services, 5% to outpatient nonphysician providers, and 3% to spending from compulsory long-term care insurance. Each additional comorbidity was accompanied by a cost increase of 563?EUR (95%?CI 488; 638). Participants with no diseases mentioned in the multimorbidity index caused average annual costs of 1,250?EUR. In contrast, respondents with 10?+ diseases caused the highest mean annual costs of 6,862?EUR.

Conclusion

Longer life expectancy has become commonplace and is often associated with the simultaneous occurrence of several diseases. A clear understanding of the impact of multimorbidity on costs is highly relevant for health policy decision makers. The present study provides a well-founded basis to analyze the relationship between multiple morbidity and associated costs due to healthcare resource consumption of older adults in Germany.     

NKG2C deletion is a risk factor of HIV infection

NK cell function is important in the immune response to HIV infection. NKG2C and NKG2A are activating and inhibitory NK cell receptors, respectively, and their only known ligand, HLA-E, demonstrates increased expression in HIV infection and presents at least one HIV-derived peptide. A variation in chromosome 12 exists in which the 16-kb section of DNA encompassing the nkg2c gene is completely absent. DNA samples of 433 HIV-1-infected patients and 280 controls were genotyped by PCR, and revealed an association of the absence variation with a higher risk of HIV infection, as well as faster progression and higher pretreatment viral loads (p<0.05, respectively). Surface NKG2C expression, analyzed by FACS, on the freshly isolated lymphocytes of 20 control and 19 HIV-infected donors revealed that NKG2C expression is genotype dependent in both populations: no NKG2C expression in the -/- groups, intermediate expression in the +/- groups, and highest expression in the +/+ groups. The comparison of NKG2C and NKG2A expression in HIV and control groups (+/- and +/+ included) indicates an increased NKG2C expression on HIV patient NK cells (p<0.05) and decreased inhibitory NKG2A expression on CD8 T cells (p<0.001), and both these effects are more striking in the +/+ genotype (p<0.005). Furthermore, a positive correlation was found between HIV viral load and the proportion of NKG2C(+) NK cells. The increased expression of NKG2C in HIV patients, in combination with the genetic association of the absence variation with an increased susceptibility to HIV infection, higher HIV viral set point, and a faster progression, indicate that NKG2C is important in the defense against HIV infection and progression.     

Association study of IRAK-M and SIGIRR genes with SLE in a large European-descent population

Objective: The aim of this study was to evaluate the relevance of genetic variants of interleukin receptor-associated kinase-M (IRAK-M) (rs11465955, rs1624395, rs1152888 and rs1370128) and single immunoglobulin IL1-1R-related molecule (SIGIRR) (rs3210908) genes in systemic lupus erythematosus (SLE) in four independent European-descent populations. Methods: Our study population consisted of a total of 2033 SLE patients and 2357 healthy controls from Spain, Germany, Italy and Argentina. The genotyping was performed using a polymerase chain reaction (PCR) system with pre-developed TaqMan allelic discrimination assay. Genetic association between the genotyped markers was determined by PLINK v1.07. Results: After a meta-analysis including these four populations, a trend of association between rs11465955 (P(meta) (-analysis) =?0.06), rs1370128 (P(meta) (-analysis) =?0.07) and rs1624395 (P(meta) (-analysis) =?0.06) polymorphisms was found. However, these differences did not reach statistical significance. In addition, we did not find any association between SLE and the rs1152888 IRAK-M (P(meta) (-analysis) =?0.13) and the rs3210908 SIGIRR (P(meta) (-analysis) =?0.40) polymorphisms after the meta-analysis. No evidence of association with IRAK-M haplotypes was found. Conclusion: These results suggest that the tested variations of IRAK-M and SIGIRR genes do not confer a relevant role in the susceptibility to SLE in European-descent populations.     

The role of diabetes on the clinical manifestations of pulmonary tuberculosis

Objective Diabetes is associated with pulmonary tuberculosis (TB), possibly due to impaired immunity, and diabetes may exacerbate the clinical manifestations of TB. Our aim was to assess the role of diabetes in the clinical manifestations of TB. Methods We studied 1250 patients with pulmonary TB in an urban population in a cross‐sectional study in Tanzania. All participants were tested for diabetes and HIV co‐infection, and TB culture intensity was assessed. Levels of white blood cells, haemoglobin, acute phase reactants, CD4 count and HIV viral load were measured, and a qualitative morbidity questionnaire was used to identify the prevalence of disease‐related symptoms. Results Tuberculosis patients with diabetes had a higher neutrophil count (B 0.5 × 10⁹ cells/l, 95% CI 0.2; 0.9, P = 0.001) than non‐diabetic TB patients. Serum C‐reactive protein (B 18.8 mg/l, CI 95% 8.2; 29.4, P = 0.001) and alpha‐1‐acid glycoprotein (B 0.2 g/l, CI 95% 0.03; 0.3, P = 0.02) were similarly higher in patients with diabetes. Diabetes did not affect culture intensity or HIV status, but self‐reported fever was three times higher among participants with diabetes than in those without diabetes (OR 2.9, CI 95% 1.5; 5.7, P = 0.002). Conclusion Diabetes is associated with small changes in the manifestations of TB, but may have little clinical significance.