A five-membered PdSbn coordination series

Five complexes of the general formula PdCl2(SbMe2Cl)n (n = 1-5) have been synthesised by combining [PdCl2(MeCN)2] and SbMe2Cl in different molar ratios in toluene. Their solid-state structures have been determined by X-ray crystallography. The complexes display considerable structural diversity: [Pd4Cl8(SbMe2Cl)4] (1, n = 1) is a chloride bridged tetramer, [Pd2Cl4(SbMe2Cl)4] (2, n = 2) is a dimer, [PdCl(SbMe2Cl)2(SbMe2Cl2)] (3, n = 3) is a supramolecular polymer, [Pd2(SbMe2Cl)8]Cl4¬ (4, n = 4) is a loosely associated dimer and [Pd(SbMe2Cl)5]Cl2 (5, n = 5) is a monomer with square pyramidal PdSb5 coordination geometry. Each structure contains secondary interactions between coordinated Sb centres and chloride ligands or anions, resulting in five-coordinate Sb in all cases with a range of Sb∙∙∙Cl bond lengths. The electronic structures of these complexes have been investigated using DFT methods including NBO and Pipek-Mezey localised orbital methods in order to interrogate both the Sb-Pd and secondary Sb∙∙∙Cl bonding

Superior MRI outcomes with alemtuzumab compared with subcutaneous interferon β-1a in MS

$\textbf{Objective:}$ To describe detailed MRI results from 2 head-to-head phase III trials, Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis Study I (CARE-MS I; NCT00530348) and Study II (CARE-MS II; NCT00548405), of alemtuzumab vs subcutaneous interferon β-1a (SC IFN-β-1a) in patients with active relapsing-remitting multiple sclerosis (RRMS). $\textbf{Methods:}$ The impact of alemtuzumab 12 mg vs SC IFN-β-1a 44 μg on MRI measures was evaluated in patients with RRMS who were treatment-naive (CARE-MS I) or who had an inadequate response, defined as at least one relapse, to prior therapy (CARE-MS II). $\textbf{Results:}$ Both treatments prevented T2-hyperintense lesion volume increases from baseline. Alemtuzumab was more effective than SC IFN-β-1a on most lesion-based endpoints in both studies ($p$ < 0.05), including decreased risk of new/enlarging T2 lesions over 2 years and gadolinium-enhancing lesions at year 2. Reduced risk of new T1 lesions ($p$ < 0.0001) and gadolinium-enhancing lesion conversion to T1-hypointense black holes ($p$ = 0.0078) were observed with alemtuzumab vs SC IFN-β-1a in CARE-MS II. Alemtuzumab slowed brain volume loss over 2 years in CARE-MS I ($p$ < 0.0001) and II ($p$ = 0.012) vs SC IFN-β-1a. $\textbf{Conclusions:}$ Alemtuzumab demonstrated greater efficacy than SC IFN-β-1a on MRI endpoints in active RRMS. The superiority of alemtuzumab was more prominent during the second year of both studies. These findings complement the superior clinical efficacy of alemtuzumab over SC IFN-β-1a in RRMS. $\textbf{ClinicalTrials.gov identifier:}$ NCT00530348 and NCT00548405. $\textbf{Classification of evidence:}$ The results reported here provide Class I evidence that, for patients with active RRMS, alemtuzumab is superior to SC IFN-β-1a on multiple MRI endpoints.Dr. Havrdova was supported by the Czech Ministry of Education, PRVOUK-P26/LF1/4. The CARE-MS studies were funded by Sanofi Genzyme and Bayer HealthCare Pharmaceuticals

The three-way relationship of polymorphisms of porcine genes encoding terminal complement components, their differential expression, and health-related phenotypes

<p>Abstract</p> <p>Background</p> <p>The complement system is an evolutionary ancient mechanism that plays an essential role in innate immunity and contributes to the acquired immune response. Three modes of activation, known as classical, alternative and lectin pathway, lead to the initiation of a common terminal lytic pathway. The terminal complement components (TCCs: C6, C7, C8A, C8B, and C9) are encoded by the genes <it>C6</it>, <it>C7</it>, <it>C8A</it>, <it>C8B</it>, <it>C8G</it>, and <it>C9</it>. We aimed at experimentally testing the porcine genes encoding TCCs as candidate genes for immune competence and disease resistance by addressing the three-way relationship of genotype, health related phenotype, and mRNA expression.</p> <p>Results</p> <p>Comparative sequencing of cDNAs of animals of the breeds German Landrace, Piétrain, Hampshire, Duroc, Vietnamese Potbelly Pig, and Berlin Miniature Pig (BMP) revealed 30 SNPs (21 in protein domains, 12 with AA exchange). The promoter regions (each ~1.5 kb upstream the transcription start sites) of <it>C6</it>, <it>C7</it>, <it>C8A</it>, <it>C8G</it>, and <it>C9</it> exhibited 29 SNPs. Significant effects of the TCC encoding genes on hemolytic complement activity were shown in a cross of Duroc and BMP after vaccination against Mycoplasma hyopneumoniae, Aujeszky disease virus and PRRSV by analysis of variance using repeated measures mixed models. Family based association tests (FBAT) confirmed the associations. The promoter SNPs were associated with the relative abundance of TCC transcripts obtained by real time RT-PCR of 311 liver samples of commercial slaughter pigs. Complement gene expression showed significant relationship with the prevalence of acute and chronic lung lesions.</p> <p>Conclusions</p> <p>The analyses point to considerable variation of the porcine TCC genes and promote the genes as candidate genes for disease resistance.</p

The Ecm11-Gmc2 complex promotes synaptonemal complex formation through assembly of transverse filaments in budding yeast

During meiosis, homologous chromosomes pair at close proximity to form the synaptonemal complex (SC). This association is mediated by transverse filament proteins that hold the axes of homologous chromosomes together along their entire length. Transverse filament proteins are highly aggregative and can form an aberrant aggregate called the polycomplex that is unassociated with chromosomes. Here, we show that the Ecm11-Gmc2 complex is a novel SC component, functioning to facilitate assembly of the yeast transverse filament protein, Zip1. Ecm11 and Gmc2 initially localize to the synapsis initiation sites, then throughout the synapsed regions of paired homologous chromosomes. The absence of either Ecm11 or Gmc2 substantially compromises the chromosomal assembly of Zip1 as well as polycomplex formation, indicating that the complex is required for extensive Zip1 polymerization. We also show that Ecm11 is SUMOylated in a Gmc2-dependent manner. Remarkably, in the unSUMOylatable ecm11 mutant, assembly of chromosomal Zip1 remained compromised while polycomplex formation became frequent. We propose that the Ecm11-Gmc2 complex facilitates the assembly of Zip1 and that SUMOylation of Ecm11 is critical for ensuring chromosomal assembly of Zip1, thus suppressing polycomplex formation

The Drosophila Zinc Finger Protein Trade Embargo Is Required for Double Strand Break Formation in Meiosis

Homologous recombination in meiosis is initiated by the programmed induction of double strand breaks (DSBs). Although the Drosophila Spo11 ortholog Mei-W68 is required for the induction of DSBs during meiotic prophase, only one other protein (Mei-P22) has been shown to be required for Mei-W68 to exert this function. We show here that the chromatin-associated protein Trade Embargo (Trem), a C2H2 zinc finger protein, is required to localize Mei-P22 to discrete foci on meiotic chromosomes, and thus to promote the formation of DSBs, making Trem the earliest known function in the process of DSB formation in Drosophila oocytes. We speculate that Trem may act by either directing the binding of Mei-P22 to preferred sites of DSB formation or by altering chromatin structure in a manner that allows Mei-P22 to form foci

The pseudogap: friend or foe of high Tc?

Although nineteen years have passed since the discovery of high temperature superconductivity, there is still no consensus on its physical origin. This is in large part because of a lack of understanding of the state of matter out of which the superconductivity arises. In optimally and underdoped materials, this state exhibits a pseudogap at temperatures large compared to the superconducting transition temperature. Although discovered only three years after the pioneering work of Bednorz and Muller, the physical origin of this pseudogap behavior and whether it constitutes a distinct phase of matter is still shrouded in mystery. In the summer of 2004, a band of physicists gathered for five weeks at the Aspen Center for Physics to discuss the pseudogap. In this perspective, we would like to summarize some of the results presented there and discuss its importance in the context of strongly correlated electron systems.Comment: expanded version, 20 pages, 11 figures, to be published, Advances in Physic

Clinical application of genetic testing for posterior uveal melanoma

Uveal melanoma is the most common primary intraocular tumor in adults, and it has a strong potential to metastasize. Traditionally, clinicopathological features of these tumors were used to provide a limited prediction of the metastatic risk. However, early genetic studies using karyotype analysis, fluorescence in situ hybridization, and comparative genetic hybridization of posterior uveal melanoma samples identified multiple chromosomal abnormalities associated with a higher risk of fatal metastasis. This correlation between specific genetic abnormalities in uveal melanoma and a patient’s risk for development of metastasis has recently been widely studied, and the development of new prognostic tests has allowed clinicians to predict this metastatic risk with increased accuracy. Such novel tests include gene expression profiling, which analyzes the RNA expression patterns of tumor cells, and multiplex ligation-dependent probe amplification, which detects deletions or and amplifications of DNA in tumor cells. This review discusses the current status of prognostic testing techniques available to clinicians and patients for posterior uveal melanomas

Planning a cluster randomized trial with unequal cluster sizes: practical issues involving continuous outcomes

BACKGROUND: Cluster randomization design is increasingly used for the evaluation of health-care, screeening or educational interventions. At the planning stage, sample size calculations usually consider an average cluster size without taking into account any potential imbalance in cluster size. However, there may exist high discrepancies in cluster sizes. METHODS: We performed simulations to study the impact of an imbalance in cluster size on power. We determined by simulations to which extent four methods proposed to adapt the sample size calculations to a pre-specified imbalance in cluster size could lead to adequately powered trials. RESULTS: We showed that an imbalance in cluster size can be of high influence on the power in the case of severe imbalance, particularly if the number of clusters is low and/or the intraclass correlation coefficient is high. In the case of a severe imbalance, our simulations confirmed that the minimum variance weights correction of the variation inflaction factor (VIF) used in the sample size calculations has the best properties. CONCLUSION: Publication of cluster sizes is important to assess the real power of the trial which was conducted and to help designing future trials. We derived an adaptation of the VIF from the minimum variance weights correction to be used in case the imbalance can be a priori formulated such as "a proportion (γ) of clusters actually recruit a proportion (τ) of subjects to be included (γ ≤ τ)"