It is a rare treat when a drug discovery program teaches us something about the biology of the process that it attempts to modulate. The paper by Maria Frank-Kamenetsky and colleagues in this issue of theJournal of Biology[1] presents a compelling example of how the search for therapeutics can provide powerful experimental tools and insights into fundamental biology, blurring the distinction between applied and basic research. By characterizing a small group of chemically similar agonists of theHedgehogsignaling pathway, Frank-Kamenetskyet al. have been able to propose a new model for how theSmoothenedcomponent of the Hedgehog-receptor complex works, and to hint at the existence of natural-ligand agonists of the Hedgehog signaling pathway (see'The bottom line'box for a summary of their work).

Randomized trials and observational studies, such as case-control studies, are often seen as opposing approaches. However, in many instances results obtained by different designs may complement each other. For instance, case-control studies on aetiology of disease may help to give the direction of future trials. In this commentary, the author discusses the purpose of randomization and observation, and under which conditions one design may be preferred to another. Randomization is useful to combat 'confounding by indication', and is therefore the design of choice for most therapeutic trials. When this confounding is not an issue, as in studies of genetic risk factors or side-effects, then case-control studies are preferred.

Genomics, or the study of genes and their function, is a burgeoning field with many new technologies. In the present review, we explore the application of genomic approaches to the study of pulmonary hypertension (PH). Candidate genes, important to the pathobiology of the disease, have been investigated. Rodent models enable the manipulation of selected genes, either by transgenesis or targeted disruption. Mutational analysis of genes in the transforming growth factor-β family have proven pivotal in both familial and sporadic forms of primary PH. Finally, microarray gene expression analysis is a robust molecular tool to aid in delineating the pathobiology of this disease.

In recent decades antenatal screening has become one of the most routine procedure of pregnancy-follow up and the subject of hot debate in bioethics circles. In this paper the rationale behind doing antenatal screening and the actual and potential problems that it may cause will be discussed. The paper will examine the issue from the point of wiew of parents, health care professionals and, most importantly, the child-to-be. It will show how unthoughtfully antenatal screening is performed and how pregnancy is treated almost as a disease just since the emergence of antenatal screening. Genetic screening and ethical problems caused by the procedure will also be addressed and I will suggest that screening is more to do with the interests of others rather than those of the child-to be.

The clinical applicability of molecular cardiology has been questioned at length and by many clinical investigators. The congenital long QT syndrome (LQTS) provides an excellent example of how tight the relationship can be between molecular biology and clinical cardiology. The advent of molecular diagnosis has demonstrated how low the penetrance can be in LQTS; this implies that there are many gene carriers who do not show the clinical phenotype and may have a normal QT interval despite being at risk. There is also a gene-specific predisposition to be at risk for cardiac arrest under different circumstances, and this provides additional basis for a gene-specific approach to therapy.

Background Computational predictions are critical for directing the experimental study of protein functions. Therefore it is paradoxical when an apparently erroneous computational prediction seems to be supported by experiment. Results We analyzed six cases where application of novel or conventional computational methods for protein sequence and structure analysis led to non-trivial predictions that were subsequently supported by direct experiments. We show that, on all six occasions, the original prediction was unjustified, and in at least three cases, an alternative, well-supported computational prediction, incompatible with the original one, could be derived. The most unusual cases involved the identification of an archaeal cysteinyl-tRNA synthetase, a dihydropteroate synthase and a thymidylate synthase, for which experimental verifications of apparently erroneous computational predictions were reported. Using sequence-profile analysis, multiple alignment and secondary-structure prediction, we have identified the unique archaeal 'cysteinyl-tRNA synthetase' as a homolog of extracellular polygalactosaminidases, and the 'dihydropteroate synthase' as a member of the β-lactamase-like superfamily of metal-dependent hydrolases. Conclusions In each of the analyzed cases, the original computational predictions could be refuted and, in some instances, alternative strongly supported predictions were obtained. The nature of the experimental evidence that appears to support these predictions remains an open question. Some of these experiments might signify discovery of extremely unusual forms of the respective enzymes, whereas the results of others could be due to artifacts.

Background Blood group genotyping is increasingly utilized for prenatal diagnosis and after recent transfusions, but still lacks the specificity of serology. In whites, the presence of antigen D is predicted, if two or more properly selected RHD-specific polymorphism are detected. This prediction must fail, if an antigen D negative RHD positive allele is encountered. Excluding RHDψ and CdeS frequent only in individuals of African descent, most of these alleles are unknown and the population frequency of any such allele has not been determined. Methods We screened 8,442 antigen D negative blood donations by RHD PCR-SSP. RHD PCR positive samples were further characterized by RHD exon specific PCR-SSP or sequencing. The phenotype of the identified alleles was checked and their frequencies in Germans were determined. Results We detected 50 RHD positive samples. Fifteen samples harbored one of three new Del alleles. Thirty samples were due to 14 different D negative alleles, only 5 of which were previously known. Nine of the 14 alleles may have been generated by gene conversion in cis, for which we proposed a mechanism triggered by hairpin formation of chromosomal DNA. The cumulative population frequency of the 14 D negative alleles was 1:1,500. Five samples represented a D+/- chimera, a weak D and three partial D, which had been missed by routine serology; two recipients transfused with blood of the D+/- chimera donor became anti-D immunized. Conclusion The results of this study allowed to devise an improved RHD genotyping strategy, the false-positive rate of which was lower than 1:10,000. The number of characterized RHD positive antigen D negative and Del alleles was more than doubled and their population frequencies in Europe were defined.

Research Article: Current Controlled Trials in Cardiovascular Medicine

Some problems with the quality of controlled clinical trials can be addressed by following these procedures: registering all trials at inception; using systematic reviews to inform the design of new studies; posting and obtaining feedback on preprints; reporting all well conducted trials, regardless of their results; reducing biased and inefficient assessment of reports submitted for publication; publishing sufficiently detailed reports; linking trial reports to relevant external information; providing readier access to reports; and reviewing and amending reports after initial publication. The launch of a new range of electronic journals by Current Controlled Trials offers an opportunity to contribute to progress in these ways.

본 데이터는 국내 종합병원에서 19XX년부터 202X년까지 항생제를 처방받은 입원, 외래 환자에 대한 모든 정보를 익명화하여 제공합니다. [데이터 범위] 항생제를 처방받은 입원 환자의 심장초음파 (경흉부,경식도) 판독 소견 [참고 데이터명] 치료결과, 환자 바탕질환 데이터, 항생제 처방 전후의 생징후 데이터, 검사실 소견 데이터, 혈액 및 검체 배양검사 결과, 처방약 데이터, 카테터 데이터, 폐기능 데이터, 심전도 데이터