Frequency of the ΔF508 deletion and G551D,R553X and G542X mutations in Yugoslav CF patients

Summary A study was undertaken to find the frequency of the F508 deletion and those of the G551D, R553X and G524X mutations among the mainly Slavic population of Serbia, Bosnia, Herzegovina, and Montenegro and compare the frequencies determined with those in other European populations. The F508 mutation was found to account for about 70% of CF genes in central Jugoslavia, where its frequency is significantly higher than elsewhere in Southern European populations.     

Long-term follow-up of patients with myocarditis and idiopathic dilated cardiomyopathy after immunomodulatory therapy

Abstract The randomized clinical trial with interferon-α (IFN) or thymic hormones versus conventional therapy was conducted in patients with myocarditis and idiopathic dilated cardiomyopathy (IDC). We enrolled 180 patients to receive IFN (3–5 million units per day) for 3 months, thymomodulin (10 mg three times per week) for 2 months, or conventional therapy alone. Patients were followed-up for 7 years after the end of treatment. Left ventricular function, exercise tolerance and survival rate were significantly better at long-term follow-up in patients treated with IFN or thymomodulin, than in conventionally treated patients. These results implicate that immune modulating therapy might represent important contribution in the treatment of myocarditis and IDC.     

Isolation and characterization of highly liganded protein from brewer's barley grain

Two basic proteins, HLP-1 and HLP-2, were isolated from brewer's barley grain (Hordeum vulgare L.) and characterized as glycoproteins with molecular masses of 16 and 13 kDa and pI values of 7.4 and 8.8, respectively. They could bind sugars, metal ions, and both hydrophobic and hydrophylic molecules of low molecular mass. These characteristics may be related to their potential plant-protecting role.     

Protein carbonylation and adipocyte mitochondrial function

Carbonylation is the covalent, non-reversible modification of the side chains of cysteine, histidine, and lysine residues by lipid peroxidation end products such as 4-hydroxy- and 4-oxononenal. In adipose tissue the effects of such modifications are associated with increased oxidative stress and metabolic dysregulation centered on mitochondrial energy metabolism. To address the role of protein carbonylation in the pathogenesis of mitochondrial dysfunction, quantitative proteomics was employed to identify specific targets of carbonylation in GSTA4-silenced or overexpressing 3T3-L1 adipocytes. GSTA4-silenced adipocytes displayed elevated carbonylation of several key mitochondrial proteins including the phosphate carrier protein, NADH dehydrogenase 1α subcomplexes 2 and 3, translocase of inner mitochondrial membrane 50, and valyl-tRNA synthetase. Elevated protein carbonylation is accompanied by diminished complex I activity, impaired respiration, increased superoxide production, and a reduction in membrane potential without changes in mitochondrial number, area, or density. Silencing of the phosphate carrier or NADH dehydrogenase 1α subcomplexes 2 or 3 in 3T3-L1 cells results in decreased basal and maximal respiration. These results suggest that protein carbonylation plays a major instigating role in cytokine-dependent mitochondrial dysfunction and may be linked to the development of insulin resistance in the adipocyte.     

Vorversuche zur Biologie von Hydra

Ohne Zusammenfassung     

Role of AP‐endonuclease (Ape1) active site residues in stabilization of the reactant enzyme‐DNA complex

Apurinic/apyrimidinic endonuclease 1 (Ape1) is an important metal‐dependent enzyme in the base excision repair mechanism, responsible for the backbone cleavage of abasic DNA through a phosphate hydrolysis reaction. Molecular dynamics simulations of Ape1 complexed to its substrate DNA performed for models containing 1 or 2 Mg²⁺‐ions as cofactor located at different positions show a complex with 1 metal ion bound on the leaving group site of the scissile phosphate to be the most likely reaction‐competent conformation. Active‐site residue His309 is found to be protonated based on pKa calculations and the higher conformational stability of the Ape1‐DNA substrate complex compared to scenarios with neutral His309. Simulations of the D210N mutant further support the prevalence of protonated His309 and strongly suggest Asp210 as the general base for proton acceptance by a nucleophilic water molecule.     

Cell‐to‐cell and type‐to‐type heterogeneity of signaling networks: insights from the crowd

Recent technological developments allow us to measure the status of dozens of proteins in individual cells. This opens the way to understand the heterogeneity of complex multi‐signaling networks across cells and cell types, with important implications to understand and treat diseases such as cancer. These technologies are, however, limited to proteins for which antibodies are available and are fairly costly, making predictions of new markers and of existing markers under new conditions a valuable alternative. To assess our capacity to make such predictions and boost further methodological development, we organized the Single Cell Signaling in Breast Cancer DREAM challenge. We used a mass cytometry dataset, covering 36 markers in over 4,000 conditions totaling 80 million single cells across 67 breast cancer cell lines. Through four increasingly difficult subchallenges, the participants predicted missing markers, new conditions, and the time‐course response of single cells to stimuli in the presence and absence of kinase inhibitors. The challenge results show that despite the stochastic nature of signal transduction in single cells, the signaling events are tightly controlled and machine learning methods can accurately predict new experimental data.     

Human MxA Protein Protects Mice Lacking a Functional Alpha/Beta Interferon System against La Crosse Virus and Other Lethal Viral Infections

The human MxA protein is part of the antiviral state induced by alpha/beta interferon (IFN-alpha/beta). MxA inhibits the multiplication of several RNA viruses in cell culture. However, its antiviral potential in vivo has not yet been fully explored. We have generated MxA-transgenic mice that lack a functional IFN system by crossing MxA-transgenic mice constitutively expressing MxA with genetically targeted (knockout) mice lacking the beta subunit of the IFN-alpha/beta receptor (IFNAR-1(-/-) mice). These mice are an ideal animal model to investigate the unique antiviral activity of human MxA in vivo, because they are unable to express other IFN-induced proteins. Here, we show that MxA confers resistance to Thogoto virus, La Crosse virus, and Semliki Forest virus. No Thogoto virus progeny was detectable in MxA-transgenic mice, indicating an efficient block of virus replication at the primary site of infection. In the case of La Crosse virus, MxA restricted invasion of the central nervous system. In contrast, Semliki Forest virus multiplication in the brain was detectable in both MxA-expressing and nonexpressing IFNAR-1(-/-) mice. However, viral titers were clearly reduced in MxA-transgenic mice. Our results demonstrate that MxA does not need the help of other IFN-induced proteins for activity but is a powerful antiviral agent on its own. Moreover, the results suggest that MxA may protect humans from potential fatal infections by La Crosse virus and other viral pathogens.     

4α-methylergosta-8,24(28)-dien-3β-ol,a minor sterol in the seed of horse chestnut

From ripe horse chestnut seed the 4α-methyl sterol fraction was isolated representing 4.5% of the unsaponifiable matter, i.e. 3 mg% of the seed. This fraction was investigated by capillary GC and combined GC-MS. It contains at least 12 components, of which 5 were identified as: obtusifoliol 4α-methylergosta-8,24(28)-dien-3β-ol, gramisterol, cycloeucalenol and citrostadienol. The distribution of these five 4α-methyl sterols in the seed was also determined and they represent about 90% of the investigated fraction. 4α-Methylergosta-8,24(28)-dien-3β-ol up to now been found in higher plants only in traces, while in this fraction it was found in the amount of about 5%.