1: Inflamm Bowel Dis. 2008 Nov 20. [Epub ahead of print]
Twin studies reveal specific imbalances in the mucosa-associated microbiota of patients with ileal Crohn's disease.
Willing B, Halfvarson J, Dicksved J, Rosenquist M, Järnerot G, Engstrand L, Tysk C, Jansson JK.
Department of Microbiology,
Background: Large interindividual variation in the composition of the intestinal microbiota between unrelated individuals has made it challenging to identify specific aspects of dysbiosis that lead to Crohn's disease (CD).Methods: To reduce variations in exposure during establishment of the gut flora and the influence of genotype, we studied the mucosa-associated microbiota of monozygotic twin pairs that were discordant (n = 6) or concordant (n = 4) for CD. DNA was extracted from biopsies collected from 5 locations between the ileum and rectum. Bacterial 16S ribosomal RNA genes were amplified and community composition assessed by terminal-restriction fragment length polymorphism, cloning and sequencing, and quantitative real-time polymerase chain reaction (PCR).Results: The microbial compositions at all biopsy locations for each individual were similar, regardless of disease state, but there were differences between individuals. In particular, individuals with predominantly ileal CD had a dramatically lower abundance (P < style="">
2: Genes Chromosomes Cancer. 2008 Nov 20. [Epub ahead of print]
Identification of a potential "hotspot" DNA region in the RUNX1 gene targeted by mitoxantrone in therapy-related acute myeloid leukemia with t(16;21) translocation.
Ottone T, Hasan SK, Montefusco E, Curzi P, Mays AN, Chessa L, Ferrari A, Conte E, Noguera NI, Lavorgna S, Ammatuna E, Divona M, Bovetti K, Amadori S, Grimwade D, Lo-Coco F.
Dipartimento di Biopatologia e Diagnostica per Immagini, University "Tor Vergata,"
The translocation t(16;21) involving RUNX1 (AML1) and resulting in the RUNX1-CBFA2T3 fusion is a rare but recurrent abnormality mostly found in therapy-related acute myeloid leukemia (t-AML) associated with agents targeting topoisomerase II (topo II). We characterized, at the genomic level, the t(16;21) translocation in a patient who developed t-AML after treatment of multiple sclerosis with mitoxantrone (MTZ). Long template nested PCR of genomic DNA followed by direct sequencing enabled the localization of RUNX1 and CBFA2T3 (ETO2) breakpoints in introns 5 and 3, respectively. Sequencing of the cDNA with specific primers showed the presence of the expected RUNX1-CBFA2T3 fusion transcript in leukemic cells. The RUNX1 intron 5 breakpoint was located at nucleotide position 24,785. This region contained an ATGCCCCAG nucleotide sequence showing approximately 90% homology to a "hotspot" DNA region ATGCCCTAG present in intron 6 of PML previously identified in therapy-related acute promyelocytic leukemia cases arising following treatment with MTZ. This study suggests a wider distribution in the human genome, and particularly at genes involved in chromosome translocations observed in t-AML, of DNA regions (hotspot) targeted by specific topo II drugs. (c) 2008 Wiley-Liss, Inc.
3: Hum Mutat. 2008 Nov 19. [Epub ahead of print]
Genomic deletions of OFD1 account for 23% of oral-facial-digital type 1 syndrome after negative DNA sequencing.
Thauvin-Robinet C, Franco B, Saugier-Veber P, Aral B, Gigot N, Donzel A, Van Maldergem L, Bieth E, Layet V, Mathieu M, Teebi A, Lespinasse J, Callier P, Mugneret F, Masurel-Paulet A, Gautier E, Huet F, Teyssier JR, Tosi M, Frébourg T, Faivre L.
Centre de Génétique, Hôpital d'Enfants, CHU Dijon, France.
Oral-facial-digital type I syndrome (OFDI) is characterised by an X-linked dominant mode of inheritance with lethality in males. Clinical features include facial dysmorphism with oral, dental and distal abnormalities, polycystic kidney disease and central nervous system malformations. Considerable allelic heterogeneity has been reported within the OFD1 gene, but DNA bi-directional sequencing of the exons and intron-exon boundaries of the OFD1 gene remains negative in more than 20% of cases. We hypothesized that genomic rearrangements could account for the majority of the remaining undiagnosed cases. Thus, we took advantage of two independent available series of patients with OFDI syndrome and negative DNA bi-directional sequencing of the exons and intron-exon boundaries of the OFD1 gene from two different European labs: 13/36 cases from the French lab; 13/95 from the Italian lab. All patients were screened by a semiquantitative fluorescent multiplex method (QFMPSF) and relative quantification by real-time PCR (qPCR). Six OFD1 genomic deletions (exon 5, exons 1-8, exons 1-14, exons 10-11, exons 13-23 and exon 17) were identified, accounting for 5% of OFDI patients and for 23% of patients with negative mutation screening by DNA sequencing. The association of DNA direct sequencing, QFMPSF and qPCR detects OFD1 alteration in up to 85% of patients with a phenotype suggestive of OFDI syndrome. Given the average percentage of large genomic rearrangements (5%), we suggest that dosage methods should be performed in addition to DNA direct sequencing analysis to exclude the involvement of the OFD1 transcript when there are genetic counselling issues. (c) 2008 Wiley-Liss, Inc.
4: Nat Prod Res. 2008 Nov;22(16):1441-1450.
Apoptotic cell death through inhibition of protein kinase CKII activity by 3,4-dihydroxybenzaldehyde purified from Xanthium strumarium.
Lee BH, Yoon SH, Kim YS, Kim SK, Moon BJ, Bae YS.
Department of Biochemistry,
The CKII inhibitory compound was purified from the fruit of Xanthium strumarium by organic solvent extraction and silica gel chromatography. The inhibitory compound was identified as 3,4-dihydroxybenzaldehyde by analysis with FT-IR, FAB-Mass, EI-Mass, (1)H-NMR and (13)C-NMR. 3,4-dihydroxybenzaldehyde inhibited the phosphotransferase activity of CKII with IC(50) of about 783 microM. Steady-state studies revealed that the inhibitor acts as a competitive inhibitor with respect to the substrate ATP. A value of 138.6 microM was obtained for the apparent K(i). Concentration of 300 microM 3,4-dihydroxybenzaldehyde caused 50% growth inhibition of human cancer cell U937. 3,4-dihydroxybenzaldehyde-induced cell death was characterised with the cleavage of poly(ADP-ribose) polymerase and procaspase-3. Furthermore, the inhibitor induced the fragmentation of DNA into multiples of 180 bp, indicating that it triggered apoptosis. This induction of apoptosis by 3,4-dihydroxybenzaldehyde was also confirmed by using flow cytometry analysis. Since CKII is involved in cell proliferation and oncogenesis, these results suggest that 3,4-dihydroxybenzaldehyde may function by inhibiting oncogenic disease, at least in part, through the inhibition of CKII activity.
5: Scand J Infect Dis. 2008 Nov 20:1-7. [Epub ahead of print]
A nosocomial outbreak of Candida parapsilosis in southern
Brillowska-Dabrowska A, Schon T, Pannanusorn S, Lonnbro N, Bernhoff L, Bonnedal J, Haggstrom J, Wistedt A, Fernandez V, Arendrup MC.
Unit of Mycology and Parasitology, Statens Serum Institute,
In a haematology ward, Candida parapsilosis was found in blood cultures from 4 patients within a month. As C. parapsilosis is known to have a restricted genetic diversity, a combined methodological approach was adopted to establish a possible epidemiological relationship among the isolates (n = 9). Multilocus sequence typing and random amplified polymorphic DNA analysis suggested a clonal origin of the isolates. The clonal origin was confirmed by microsatellite analysis, a method that displayed the highest discriminatory level and readily differentiated cluster isolates from 2 epidemiologically unrelated strains of C. parapsilosis. The use of novel methods of genotyping such as microsatellite analysis will facilitate epidemiological investigations of potential clonal outbreaks of fungaemia.
6: J Comput Aided Mol Des. 2008 Nov 21. [Epub ahead of print]
Binding of the Zn(2+) ion to ferric uptake regulation protein from E. coli and the competition with Fe(2+) binding: a molecular modeling study of the effect on DNA binding and conformational changes of Fur.
Jabour S, Hamed MY.
Computational Science Program, Chemistry Department,
The three dimensional structure of Ferric uptake regulation protein dimer from E. coli, determined by molecular modeling, was docked on a DNA fragment (iron box) and Zn(2+) ions were added in two steps. The first step involved the binding of one Zn(2+) ion to what is known as the zinc site which consists of the residues Cys 92, Cys 95, Asp 137, Asp141, Arg139, Glu 140, His 145 and His 143 with an average metal-Nitrogen distance of 2.5 A and metal-oxygen distance of 3.1-3.2 A. The second Zn(2+) ion is bound to the iron activating site formed from the residues Ile 50, His 71, Asn 72, Gly 97, Asp 105 and Ala 109. The binding of the second Zn(2+) ion strengthened the binding of the first ion as indicated by the shortening of the zinc-residue distances. Fe(2+), when added to the complex consisting of 2Zn(2+)/Fur dimer/DNA, replaced the Zn(2+) ion in the zinc site and when a second Fe(2+) was added, it replaced the second zinc ion in the iron activating site. The binding of both zinc and iron ions induced a similar change in Fur conformations, but shifted residues closer to DNA in a different manner. This is discussed along with a possible role for the Zn(2+) ion in the Fur dimer binding of DNA in its repressor activity.
7: J Neuroimmune Pharmacol. 2008 Nov 21. [Epub ahead of print]
TNF Alpha Production in Morphine-Treated Human Neural Cells Is NF-kappaB-Dependent.
Sawaya BE, Deshmane SL, Mukerjee R, Fan S, Khalili K.
Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, 1900N 12th Street, Philadelphia, PA, 19122, USA, sawaya@temple.edu.
The cytokine tumor necrosis factor alpha (TNFalpha) is a key factor in several inflammatory diseases and its levels increase in response to a variety of internal or external stimuli. The regulation of the TNFalpha promoter is mediated by several transcription factors including the nuclear factor kappa B protein (NF-kappaB). This study examines the role of NF-kappaB in the regulation of TNFalpha production by morphine in microglia. Using reverse transcriptase polymerase chain reaction, we demonstrated the presence of morphine receptors in these cells. We next demonstrated the ability of morphine to promote TNFalpha production and secretion by these cells using a cytokine array assay. Transient transfection experiments led to the identification of the region located between nucleotides -751 and -615 within the TNFalpha promoter as being responsive to morphine treatment. The DNA sequence of this region contains a motif indicative of a potential NF-kappaB binding site. The use of a small interfering RNA directed against p65, a subunit of NF-kappaB, demonstrated that TNFalpha induction by morphine is NF-kappaB-dependent. All of the effects of morphine were reversed by the morphine inhibitor, naloxone. These data provide important insights into the effects of morphine on microglia.
8: Neurochem Res. 2008 Nov 21. [Epub ahead of print]
Neuronal Mitochondrial Toxicity of Malondialdehyde: Inhibitory Effects on Respiratory Function and Enzyme Activities in Rat Brain Mitochondria.
Long J, Liu C, Sun L, Gao H, Liu J.
Institute for Brain Aging and Dementia,
Malondialdehyde (MDA) is a product of oxidative damage to lipids, amino acids and DNA, and accumulates with aging and diseases. MDA can possibly react with amines so as to modify proteins and inactivate enzymes; it can also modify nucleosides so as to cause mutagenicity. Brain mitochondrial dysfunction is a major contributor to aging and neurodegenerative diseases. We hypothesize that MDA accumulated during aging targets mitochondrial enzymes so as to cause further mitochondrial dysfunction and additional contributions to aging and neurodegeneration. Herein, we investigated the neuronal mitochondrial toxic effects of MDA on mitochondrial respiration and activities of enzymes (mitochondrial complexes I-V, alpha-ketoglutarate dehydrogenase (KGDH) and pyruvate dehydrogenase (PDH)), in isolated rat brain mitochondria. MDA depressed mitochondrial membrane potential, and also showed a dose-dependent inhibition of mitochondrial complex I- and complex II-linked respiration. Complex I and II, and PDH activities were depressed by MDA at >/=0.2 mumol/mg; KGDH and complex V were inhibited by >/=0.4 and >/=1.6 mumol MDA/mg, respectively. However, MDA did not have any toxic effects on complex III and IV activities over the range 0-2 mumol/mg. MDA significantly elevated mitochondrial reactive oxygen species (ROS) and protein carbonyls at 0.2 and 0.002 mumol/mg, respectively. As for the antioxidant defense system, a high dose of MDA slightly decreased mitochondrial GSH and superoxide dismutase. These results demonstrate that MDA causes neuronal mitochondrial dysfunction by directly promoting generation of ROS and modifying mitochondrial proteins. The results suggest that MDA-induced neuronal mitochondrial toxicity may be an important contributing factor to brain aging and neurodegenerative diseases.
9: Mod Rheumatol. 2008 Nov 22. [Epub ahead of print]
A1330V polymorphism of low-density lipoprotein receptor-related protein 5 gene and self-reported incident fractures in Japanese female patients with rheumatoid arthritis.
Furuya T, Urano T, Ikari K, Kotake S, Inoue S, Hara M, Momohara S, Kamatani N, Yamanaka H.
We attempted to determine whether the A1330V polymorphism of the low-density lipoprotein receptor-related protein 5 (LRP5) gene is associated with a risk of self-reported incident fractures and hypercholesterolemia in Japanese patients with rheumatoid arthritis (RA). DNA samples, laboratory data, and clinical data were obtained from 563 female RA patients who participated in the Institute of Rheumatology Rheumatoid Arthritis (IORRA) observational cohort study. A1330V genotyping was performed using a custom TaqMan assay. Multiple logistic regression analyses showed that any incident fracture was significantly associated with older age (P = 0.000000036), high Japanese Health Assessment Questionnaire (J-HAQ) score (P = 0.016), and high daily prednisolone dose (P = 0.031), but not with the A1330V polymorphism, while serum total cholesterol levels >/=220 mg/100 mL were independently correlated with baseline older age (P = 0.00011), low J-HAQ score (P = 0.0098), high body mass index (P = 0.024), 1330VV genotype (P = 0.027), and high daily prednisolone dose (P = 0.031). Our results suggest that this LPR5 polymorphism does not appear to be a clinically useful marker for the prediction of fracture risk in Japanese female RA patients, although it is associated with increased serum total cholesterol levels.
10: World J Surg. 2008 Nov 21. [Epub ahead of print]
Nonviral Delivery for Genomic Therapy of Cancer.
Templeton NS.
Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, M/S 390, Houston, TX, 77030, USA, NANCYT@bcm.tmc.edu.
We have developed improved liposomal nanoparticles that efficiently condense nucleic acids, proteins, viruses, drugs, and mixtures of these agents on the interior of bilamellar invaginated structures (BIVs) produced by a novel extrusion procedure. The liposomal complexes have extended half-life in the circulation, serum stability, and broad biodistribution; are targetable to specific organs and cell types; can penetrate through tight barriers in several organs; are fusogenic with cell membranes and avoid endosomes; are optimized for nucleic acid:lipid ratio and colloidal suspension in vivo; can be size fractionated to produce totally homogeneous populations of complexes prior to injection; are nontoxic, nonimmunogenic, and can be repeatedly administered; and they are stable in liquid suspensions and freeze-dried formulations. We can add specific ligands either by ionic interactions or by covalent attachments to the surface of these nucleic acid-liposome complexes to accomplish targeted delivery to specific cell surface receptors. Furthermore, the charge on the surface of these complexes can be modified to avoid uptake by nontarget cells using our novel technology called "reversible masking." We have also achieved high-dose systemic delivery of these complexes without toxicity in vivo by further purification of plasmid DNA. At present, these complexes are injected intravenously into patients in clinical trials to treat lung cancer and will be used in upcoming trials to treat breast, pancreatic, and head and neck cancers. Notably, BIV complexes are being injected intravenously into patients with non-small-cell lung carcinoma who have failed to respond to chemotherapy. These patients are living longer and have demonstrated objective responses, including tumor regression.
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