Automated method for determination of glutardialdehyde residues in flexible endoscopes after disinfection

Glutardialdehyde (GDA) is the most commonly used disinfectant for flexible endoscopes. After inappropriate rinsing of endoscopes residual GDA in the narrow endoscope channels may lead to toxic effects in patients. Common methods for determination of aldehydes in water involve derivatization with 2,4-dinitrophenylhydrazine (DNPH), liquid-liquid or solid-phase extraction and HPLC determination. Since derivatization and extraction is both time-consuming and labor-intensive only a small number of samples can be measured. Thus, we developed a fully automated method which includes a conventional HPLC system, a programmable autosampler, and UV detection. After GDA derivatization using DNPH the samples remain in the aqueous phase and no preconcentration of the analyte is necessary. The samples are automatically derivatized through the autosampler. While derivatization in one sample takes place the previous sample is injected and measured by HPLC. Our method is well suited for screening residual GDA in endoscopes as it is both time- and labor-saving.     

Ethical and regulatory issues arising from proteomic research and technology

Over the last two decades, medical research has begun to make extensive use of products of human origin in therapeutics, oncology, and most recently, in genetic diseases. This has raised many ethical issues involving patient rights, including issues of consent. Besides informed consent, researchers should address several topics when designing studies using human tissues. Reward for the patient should be kept minimal. Sample transfer should be organized along non-profit lines, at least in Europe. Sampling procedures should be at no risk for human volunteers, and at minimal risk for patients. Biosafety aspects should be addressed, in particular when international collaborations are intended or when collaboration is existing between academia and industry. Regulations on importation and exportation of human tissues should be observed. Data acquisition and storage should be addressed in accordance with national data protection regulations, in particular when using computerized databases. If follow-up information is to be taken, the authorization for such information should be requested. The right for patient's information (or for no information) on the research results should also be addressed. The issues of validation and patenting should be also solved, usually by informing the patient that he/she will have no commercial rights on potential research results. The patient should be told if the samples are transferred to another research laboratory or private company. Samples and related data should be destroyed on request at any time point during the course of the study. If possible, traceability of the donor should be ensured.     

Research needs for lion conservation in West and Central Africa

The lion has historically probably been widespread at low densities in West and Central Africa, nowadays they are largely restricted to small isolated populations inside protected areas. The total number is probably between 1200 and 2700, the best possible guesstimate would be 1700. Mankind is the main cause for the suspected decline of lion populations, both inside and outside protected areas. Very little research has been done on West and Central African lions a few examples are summarized here. The international community is slowly becoming aware of threats to lions in the region and some initiatives for lion conservation have started.     

Molecular monitoring in malaria vaccine trials

Molecular techniques offer new approaches for malaria field trials, particularly PCR techniques, which facilitate accurate diagnosis of Plasmodium infections and increase the power of estimates of vaccine effects on malaria prevalence or incidence. Molecular methods also help to assess selective effects of vaccines. Longitudinal genotyping data can be used to initiate novel analyses of parasite dynamics, including estimates of incidence of infection with individual parasite clones and duration of infections. In addition, high-throughput methods can be used to apply these techniques routinely in randomized controlled trials, as well as programme-based evaluations of malaria control.     

Hormone replacement therapy in rheumatoid arthritis is associated with lower serum levels of soluble IL-6 receptor and higher insulin-like growth factor 1

Hormone replacement therapy (HRT) modulates the imbalance in bone remodeling, thereby decreasing bone loss. Sex hormones are known to influence rheumatic diseases. The aim of this study was to investigate the effects of HRT on the serum levels of hormones and cytokines regulating bone turnover in 88 postmenopausal women with active rheumatoid arthritis (RA) randomly allocated to receive HRT plus calcium and vitamin D3 or calcium and vitamin D3 alone for 2 years. An increase in estradiol (E2) correlated strongly with improvement of bone mineral density in the hip (P < 0.001) and lumbar spine (P < 0.001). Both baseline levels and changes during the study of IL-6 and erythrocyte sedimentation rate were correlated positively (P < 0.001). HRT for 2 years resulted in an increase of the bone anabolic factor, insulin-like growth factor 1 (IGF-1) (P < 0.05) and a decrease of serum levels of soluble IL-6 receptor (sIL-6R) (P < 0.05), which is known to enhance the biological activity of IL-6, an osteoclast-stimulating and proinflammatory cytokine. Baseline levels of IL-6 and IGF-1 were inversely associated (P < 0.05), and elevation of IGF-1 was connected with decrease in erythrocyte sedimentation rate (P < 0.05) after 2 years. Interestingly, increase in serum levels of E2 was associated with reduction of sIL-6R (P < 0.05) and reduction of sIL-6R was correlated with improved bone mineral density in the lumbar spine (P < 0.05). The latter association was however not significant after adjusting for the effect of E2 (P = 0.075). The influences of IGF-1 and the IL-6/sIL-6R pathways suggest possible mechanisms whereby HRT may exert beneficial effects in RA. However, to confirm this hypothesis future and larger studies are needed.     

Persistent use of false myeloma cell lines

Multiple myeloma (MM) is a neoplasm of a terminally differentiated B-cell. Human myeloma cell lines were shown to be suitable model systems for use in various fields of the biological sciences. Within the last 20 years more than 100 cell lines have been established. So-called 'myeloma cell lines' have been previously reported and are still widely used which are in reality Epstein-Barr virus (EBV)-positive B-lymphoblastoid cell lines. The presence of the EBV-genome in residual normal B-cells provides them with a selective growth advantage after explantation. Cell lines represent an extremely important resource for research in a variety of fields and disciplines. As the cell lines are used as in vitro model systems in lieu of primary material, it is crucial that the cells in the culture flasks faithfully correspond to the purported objects of study. On closer examination, the use of false cell lines may be seen to invalidate a significant percentage of scientific work, or at least cast doubts on the relevance of these in vitro results to the cell type or tumor in vivo. Ultimately, use of cross-contaminated cell lines is a waste of human and material resources. Henceforth, it should be mandatory to prove the proper derivation of each new cell line by comparing DNA fingerprints or karyotypes of the patient's primary cells and the cultured cells. The availability of well characterized and authenticated bona fide MM cell lines is of great importance for the study of the biology, etiology and treatment of the disease.     

The circling behavior of the deafblind LEW-<Emphasis Type="Italic">ci2</Emphasis> rat is linked to a segment of RNO10 containing <Emphasis Type="Italic">Myo15</Emphasis> and <Emphasis Type="Italic">Kcnj12</Emphasis>

The LEW/Ztm-ci2 rat is an autosomal recessive mutant that displays circling behavior, deafness, progressive retinopathy, locomotor hyperactivity, ataxia, and opisthotonus. We performed a genome-wide scan of a (LEW/Ztm-ci2 × BN/Ztm) F₁ × LEW/Ztm-ci2 backcross population with anonymous microsatellite markers to analyze the genetics of this mutant rat. This linkage analysis demonstrated a very strong association of RNO10 SSLP markers to the phenotype with a core region in the central part of the chromosome. The knowledge of genes mapping to this part of the rat genome and their linkage to SSLP markers is still poor. We developed SSLP markers closely linked to genes, which might be responsible for the mutant phenotype by using the growing amount of rat-specific DNA sequences available at World Wide Web databases. Application of this method facilitated the search for candidate genes for the phenotype of the LEW-ci2 rat. We were able to map Myo15 and its neighboring genes, Znf179 and Aldh3a1, to the region of interest and Myo1c to a more distal location on RNO10. Further rat BAC clones were used to create a physical map of the region of interest. This map revealed the position of further genes. Among those is Kcnj12. Owing to their localization on RNO10 and their involvement in a similar pathology in human and mouse, Myo15 and Kcnj12 can be regarded as candidate genes for the deafblind phenotype of the LEW-ci2 rat.