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Kidney gene database: a curated and integrated database of genes involved in kidney disease.

PURPOSE: We have created a curated and integrated database, the Kidney Gene Database (KGDB) (http://www.urogene.org/kgdb) that contains current information about genes or genomic loci involved in human kidney disease. MATERIALS AND METHODS: Genes that undergo molecular, genetic or epigenetic events that affect kidney function are identified through a biomedical literature search and catalogued in the database. RESULTS: Events that are currently screened for are gene amplification, mutation, deletion, polymorphism, loss of heterozygosity, DNA methylation and DNA hypomethylation. In addition, genes that are uniquely expressed in the kidney, as determined by analyzing the expressed sequence tags database and the Serial Analysis of Gene Expression database, are also included in KGDB. For each gene KGDB provides basic information about the gene product, a tissue type gene expression profile, links to protein, mRNA and genomic DNA sequence information, relevant literature citations and cross-references to other databases. CONCLUSIONS: We present KGDB, which is to our knowledge the first curated and integrated database of genes involved in human kidney disease. KGDB is free, widely accessible and easy to use, and it provides a wealth of relevant information. In addition, KGDB will be continuously updated every 6 months to include new information published in the biomedical literature or in gene expression databases. We envision that KGDB will serve as a valuable resource for scientists and clinicians.

Databases, Genetic↗

The parp-1 inhibitor ino-1001 facilitates hemodynamic stabilization without affecting DNA repair in porcine thoracic aortic cross-clamping-induced ischemia/reperfusion.

Inhibition of poly (ADP-ribose) polymerase 1 (PARP-1) improved hemodynamics and organ function in various shock models induced by sepsis or ischemia/reperfusion. PARP-1, however, is also referred to play a pivotal role for the maintenance of genomic integrity. Therefore, we investigated the effect of the PARP-1 blocker INO-1001 on hemodynamics, kidney function, and DNA damage and repair during porcine thoracic aortic cross-clamping. The animals underwent 45 min of aortic cross-clamping after receiving vehicle (n=9) or i.v. INO-1001 (n=9; total dose, 4 mg.kg, administered both before clamping and during reperfusion), data were recorded before clamping, before declamping, and 2 and 4 h after declamping. During reperfusion, continuous i.v. norepinephrine was incrementally adjusted to maintain blood pressure greater than or equal to 80% of the pre-clamping level. The plasma INO-1001 levels analyzed with high-pressure liquid chromatography were 1 to 1.4 micromol/L and 0.4 to 0.6 micromol/L before and after clamping, respectively. Although INO-1001-treated animals required less norepinephrine support, kidney function was comparable in the 2 groups. There was no intergroup difference either in the time course of DNA damage and repair (comet assay) as assessed both in vivo in whole blood before surgery, before clamping, before declamping, 2 h after declamping, and ex vivo in isolated lymphocytes (Ficoll gradient) sampled immediately before clamping and analyzed before, immediately, and 1 and 2 h after exposure to 4 bar 100% O2 for 2 h. There was no difference either in the expression of the cyclin-dependent kinase inhibitor gene, p27, in the kidney (immunohistochemistry). The reduced norepinephrine requirements during reperfusion suggest a positive inotropic effect of INO-1001, as demonstrated by other authors. In our model, INO-1001 proved to be safe with respect to DNA repair.

Animals↗

Single primer pair for PCR identification of Candida parapsilosis group I isolates.

A DNA fragment, isolated from a genomic DNA mini-library of Candida parapsilosis group I reference strain ATCC 22019, was sequenced and characterised. The fragment was first probed by Southern blotting against a pool of DNA from several yeasts. The hybridisation tests revealed that the probe was specific for strain ATCC 22019 and 49 (90.74%) of 54 C. parapsilosis clinical and soil isolates that were attributed to C. parapsilosis group I by the electrophoretic images of their restriction fragment length polymorphisms (RFLPs) and electrophoretic karyotype (EK). The remaining five negative isolates, according to the same criteria, were attributed to group II (one isolate) and III (four isolates). Two primers were selected from the probe DNA sequence and a PCR-based test was developed for specifically detecting C. parapsilosis group I isolates, which represent the majority of the common clinical isolates. The PCR assay confirmed the Southern hybridisation results. This PCR assay could be a simple and reproducible tool for the rapid, sensitive and species-specific identification of C. parapsilosis major group I isolates.

Base Sequence↗

Phenotypic consequences of red-white colony type variation in Mycobacterium avium.

Mycobacterium avium undergoes reversible morphotypic switching between the virulent transparent colony type and the less virulent opaque colony type. A new morphotypic switch in M. avium, termed red-white, that becomes visible when opaque colonies of clinical isolates are grown on agar media containing Congo red, was recently described. White opaque (WO) variants were found to be more resistant to multiple antibiotics than were red opaque (RO) variants. The present paper reports that transparent derivatives of RO and WO clones retain the differential Congo red binding properties of their opaque parents, indicating that the opaque-transparent switch operates independently of the red-white switch. White transparent variants were more resistant to clarithromycin and rifampin in vitro, and better able to survive within human macrophages, than their red transparent counterparts. Neither red nor white variants were markedly favoured during growth in vitro; however, red variants were better able to spread on soft agar (sliding motility), a potential selective advantage under some environmental circumstances. White-to-red switching was frequently observed in vitro and was accompanied by decreased antibiotic resistance and increased motility. Red-to-white switching has yet to be observed in vitro, indicating that the red morphotype is very stable. Significantly, some widely studied laboratory reference strains of M. avium, including strain 2151 and the genome sequence strain 104, are stable red clones. These strains are intrinsically antibiotic resistant and virulent in animal models, but they may not express genes encoding the elevated levels of antibiotic resistance and intracellular survival observed in white variants.

Anti-Bacterial Agents↗

Genomovars 11 to 18 of Pseudomonas stutzeri, identified among isolates from soil and marine sediment.

Amongst 440 strains of Pseudomonas stutzeri isolated from soil and marine sediment for a population genetic study, eight strains were each presumed to represent a novel genomic group and were compared with each other and to reference strains of P. stutzeri genomovars 1 to 10 and other Pseudomonas species by DNA-DNA hybridization, 16S rRNA and internally transcribed 16S-23S rRNA spacer region (ITS1) sequences and basic physiological properties defining the species. While 16S rRNA and ITS1 gene sequences positioned the eight strains within the phylogenetic branch of P. stutzeri, the DNA-DNA hybridizations with reference strains of the 10 described genomovars and among the novel strains were generally below 70 %, which is the threshold for species and genomovar differentiation. Since the physiological properties studied in the eight strains fitted the profile of P. stutzeri, eight new genomovars of P. stutzeri, numbered 11 to 18, are proposed, with strains 28a50, 28a39, 28a22, 28a3, 4C29, 24a13, 24a75 and MT-1 being the reference strains. The highly transformable reference strain 28a3 of genomovar 14 had a localized 16S rRNA gene sequence tag characteristic of genomovar strains 2 and 3, suggesting a possible horizontal gene transfer event involving part of the 16S rRNA gene.

Bacterial Typing Techniques↗

Nucleotide variation in Sabin type 2 poliovirus from an immunodeficient patient with poliomyelitis.

The molecular and antigenic properties of a Sabin-like type 2 poliovirus, isolated from the stool samples of a 2-year-old agammaglobulinaemic child who developed paralysis 1 year after receiving the third dose of oral poliovirus vaccine, were analysed. The virus revealed 0.88 % genome variation in the VP1 region compared with the standard reference strain, compatible with replication of the virus in the intestine over approximately 1 year. The typical mutations in the 5'NCR and VP1 associated with reversion to neurovirulence for Sabin type 2 poliovirus were found. Despite this, the virus was characterized by both PCR and ELISA tests as Sabin-like and showed temperature sensitivity and neurovirulence in transgenic mice typical of the Sabin type 2 vaccine strain. Gammaglobulin replacement therapy led rapidly to virus clearance, which, when combined with treatment with the antiviral drug pleconaril, stopped virus excretion; no further virus shedding occurred. This is the first case of poliomyelitis and long-term excretion from an immunodeficient patient to be reported in Italy through the active 'Acute Flaccid Paralysis' surveillance system.

5' Untranslated Regions↗

Detection of infectious hepatitis A virus by integrated cell culture/strand-specific reverse transcriptase-polymerase chain reaction.

AIMS: A novel integrated cell culture/strand-specific reverse transcriptase-polymerase chain reaction (RT-PCR) assay was established for detection of infectious hepatitis A virus (HAV). METHODS AND RESULTS: The specificity of tagged RT-PCR was assessed using HAV genomic positive-strand RNA extracted from HAV virions as reference. Water samples artificially contaminated with infectious or formalin-inactivated HAV were subjected to integrated cell culture (ICC)/RT-PCR and ICC/strand-specific RT-PCR assays respectively. The tagged RT-PCR had high specificity for HAV negative-strand RNA. By demonstrating the formation of negative-strand RNA replicative intermediate, ICC/strand-specific RT-PCR can distinguish between infectious and non-infectious HAV. The described method detected infectious HAV at inoculation level of 10(0) TCID50 per flask within 4 days. CONCLUSIONS: The ICC/strand-specific RT-PCR is a novel, rapid, sensitive and reliable method for detection of infectious HAV. SIGNIFICANCE AND IMPACT OF THE STUDY: Coupled with a suitable virus concentration and purification system, ICC/strand-specific RT-PCR will provide a novel and rapid method for detection of infectious HAV in clinical, environmental and food samples. This assay may be used as an alternative method to test the effective inactivation of inactivated virus vaccines. It may also be adapted to assess the efficacy of disinfection of HAV and enteric viruses in foods and water.

Cell Line↗

Isolation and characterization of a rat liver alkaline phosphatase gene. A single gene with two promoters.

Structural analysis of 55 nearly full-length cDNA clones revealed heterogeneity in the 5'-untranslated regions of rat liver alkaline phosphatase mRNAs. The 5' extremities diverged into two totally unrelated sequence stretches at the position 88 nucleotides upstream of the initiation codon ATG. These two sequences, referred to as E1 and E2, were assigned on the genome about 36,000 base pairs (36 kbp) and 10 kbp upstream, respectively, of the exon coding for the 5'-most part of the common region. The gene consisted of 13 exons, including E1 and E2, and spanned about 56 kbp. The 11 exons (E3 to E13) following E1 and E2 were shared in common by the E1-type and the E2-type mRNAs. Analyses by S1 nuclease mapping and primer extension revealed the presence of two independent transcription-initiation sites specific to each of the E1 and E2 sequences. These results are interpreted as indicating a possible alternative usage of two leader exons, hence the presence of two independent promoters. Structural features of these putative promoters are described in the context of transcriptional fundamental and regulatory cis-elements.

Alkaline Phosphatase↗

In search of a stem cell hierarchy in the human breast and its relevance to breast cancer evolution.

By deliberate analogy with the well-established concept of hematopoiesis, the term "mammopoiesis" is occasionally used to describe the development of the different cellular lineages and functional units in the mammary gland. The use of this term signifies a strong bias towards the idea that tissue homeostasis during mammary development, pregnancy, lactation and involution is brought about by the action of somatic stem cells characterized by longevity and multipotency. The progenies hereof eventually differentiate into structurally and functionally well-defined ductal-lobular units. During the past two decades evidence of such a notion in the mouse has developed from being largely circumstantial based on non-clonal in vivo experiments to a quite elaborate characterization of individual candidate stem cells by a number of different properties. Within tumor biology this has led to a renaissance of the concept of tumors as caricatures of tissue renewal. Thus, recent molecular classification of breast cancer based on genome wide expression analysis operates with different subtypes with specific reference to the normal luminal epithelial and myoepithelial/basal lineages in the breast. Apparently some tumors are lineage restricted and others differentiate more broadly as if they have preserved some stem-like properties. This holds promise for the existence of a stem cell hierarchy, the understanding of which may prove to be instrumental in further dissecting the histogenesis of breast cancer evolution. Most attention has been devoted to the question of different cellular origins of cancer subtypes and different susceptibilities of possible stem cells to gain or loss of oncogenes and tumor suppressor genes, respectively. Invaluable progress has been made over the past two decades in culture technology not only in terms of population doubling and clonal growth, but also the availability of lineage specific markers, cell sorting, and three-dimensional functional assays for tissue specific morphogenesis. Transcriptional profiling of stem cell zones has unraveled a hitherto unknown preservation of signaling pathways for maintenance of stem cell properties across tissue boundaries and species. Somatic stem cells have therefore been narrowed down to specific anatomic locations not only in rapidly renewing tissues such as skin and skin derivatives, but also in tissues with slower turnover times, such as lung, kidney and prostate. It is therefore now possible to integrate this information in a search for similar cells within the breast. Even if cell turnover after birth is provided exclusively by dividing lineage-restricted cells, more information about the robustness of breast differentiation programs during tumor progression is still very much required. Complete knowledge of the primary cell of origin of breast cancer and the mechanisms that influence differentiation programs during tumor initiation, promotion and progression may be crucial for the development of novel non-toxic therapies that influence tumor cell behaviour. The scope of this review is to discuss reports that have begun to elucidate the topographic location, key cellular type and lineage fidelity in culture and xenograft models of candidate human breast stem cells and their differentiated progenies with particular emphasis on comparison with the differentiation programs of tumor subtypes.

Animals↗

Speciation of Campylobacter coli, C. jejuni, C. helveticus, C. lari, C. sputorum, and C. upsaliensis by matrix-assisted laser desorption ionization-time of flight mass spectrometry.

Multiple strains of Campylobacter coli, C. jejuni, C. helveticus, C. lari, C. sputorum, and C. upsaliensis isolated from animal, clinical, or food samples have been analyzed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Whole bacterial cells were harvested from colonies or confluent growth on agar and transferred directly into solvent and then to a spot of dried 3-methoxy-4-hydroxycinnamic acid (matrix). Multiple ions in the 5,000- to 15,000-Da mass range were evident in spectra for each strain; one or two ions in the 9,500- to 11,000-Da range were consistently high intensity. "Species-identifying" biomarker ions (SIBIs) were evident from analyses of multiple reference strains for each of the six species, including the genome strains C. jejuni NCTC 11168 and C. jejuni RM1221. Strains grown on nine different combinations of media and atmospheres yielded SIBI masses within +/-5 Da with external instrument calibration. The highest-intensity C. jejuni SIBIs were cytosolic proteins, including GroES, HU/HCj, and RplL. Multiple intraspecies SIBIs, corresponding probably to nonsynonymous nucleotide polymorphisms, also provided some intraspecies strain differentiation. MALDI-TOF MS analysis of 75 additional Campylobacter strains isolated from humans, poultry, swine, dogs, and cats revealed (i) associations of SIBI type with source, (ii) strains previously speciated incorrectly, and (iii) "strains" composed of more than one species. MALDI-TOF MS provides an accurate, sensitive, and rapid method for identification of multiple Campylobacter species relevant to public health and food safety.

Animals↗

Identification of six putative novel human papillomaviruses (HPV) and characterization of candidate HPV type 87.

Six putative novel human papillomavirus (HPV) types were detected by using general primers for a conserved L1 HPV region in patients examined in gynecologic centers. One of the isolates, detected in samples from 4 patients with koilocytic atypia at cervical cytology (3 of whom were also infected with human immunodeficiency virus type 1), was completely sequenced, identified as a new HPV genotype, and designated candidate HPV87 (candHPV87) by the Reference Center for Human Papillomavirus. candHPV87 shows the classic HPV genome organization and the absence of a functional E5 coding region. Phylogenetic analysis documented that the candHPV87 genome clusters within the A3 group of HPVs, together with HPV61, HPV72, HPV83, HPV84 and candHPV86, which have been completely sequenced, and a number of other putative novel genotypes (two of which are described in this work), which have been partially characterized. To address the growth-enhancing potential of candHPV87, the E6 and E7 putative coding regions were cloned and expressed in tissue cultures. The data indicate that both proteins stimulate cell division in tissue cultures more than those of low-risk HPVs, though not as much as those of HPV16. Taken together, the clinical, molecular, and biological data suggest that the novel papillomavirus characterized in the present study is a low- to intermediate-risk HPV.

Genome, Viral↗

Comprehensive survey of common genetic variation at the plasminogen activator inhibitor-1 locus and relations to circulating plasminogen activator inhibitor-1 levels.

BACKGROUND: Using a linkage disequilibrium (LD)-based approach, we sought to comprehensively define common genetic variation at the plasminogen activator inhibitor-1 (PAI-1) locus and relate common single nucleotide polymorphisms (SNPs) and haplotypes to plasma PAI-1 levels. METHODS AND RESULTS: In reference pedigrees, we defined LD structure across a 50-kb genomic segment spanning the PAI-1 locus via a dense SNP map (1 SNP every 2 kb). Eighteen sequence variants that capture underlying common genetic variation were genotyped in 1328 unrelated Framingham Heart Study participants who had plasma PAI-1 antigen levels measured. Regression analyses were used to examine associations of individual SNPs and of inferred haplotypes with multivariable-adjusted PAI-1 levels. Two genetic variants, SNP rs2227631 and the 4G/5G polymorphism, were strongly associated (P<0.0001) with PAI-1 levels. SNP rs2227631 is in tight LD (D'=0.97, r2=0.78) with the 4G/5G polymorphism, which makes it difficult to distinguish which of these 2 polymorphisms is responsible for the association with PAI-1 levels. In stepwise analysis considering all polymorphisms tested, 3 SNPs, rs2227631 (or the correlated 4G/5G polymorphism), rs6465787, and rs2227674, each explained 2.5%, 1%, and 1%, respectively, of the residual variance in multivariable-adjusted PAI-1 levels (stepwise P<0.0001, P=0.04, and P=0.03, respectively). A single common haplotype, at 50% frequency among Framingham Heart Study participants, was strongly associated with higher PAI-1 levels (haplotype-specific P=0.00001). The susceptibility haplotype harbors the minor alleles of SNP rs2227631 and the 4G/5G polymorphism. CONCLUSIONS: Three sequence variants at the PAI-1 locus, in sum, explain approximately 5% of the residual variance in multivariable-adjusted PAI-1 levels. For quantitative cardiovascular traits such as circulating biomarkers, defining LD structure in a candidate gene followed by association analyses with both SNPs and haplotypes is an effective approach to localize common susceptibility alleles.

Aged↗

Assessment of genomic damage in colorectal cancer by DNA fingerprinting: prognostic applications.

PURPOSE: Here we evaluate the prognostic significance of the relative value of genomic damage assessed by DNA fingerprinting in colorectal cancer. MATERIALS AND METHODS: Sixty-three tumor and paired normal mucosa samples were included in the study. Genomic damage was assessed by comparative analysis of paired normal and tumor tissue DNA fingerprints by the arbitrarily primed polymerase chain reaction (AP-PCR). Decreases and increases of intensity in bands were computed and referred to the total number of visualized bands per case. An index reflecting the genomic damage fraction (GDF), with separated values for losses and gains, was obtained for each tumor. This index was used to determine molecular and clinicopathologic correlates after exclusion of eight cases displaying microsatellite instability. RESULTS: Fifty-five cases were considered for the statistical analysis. The average fraction of altered bands per tumor was 0.287+/-0.121. When losses and gains were computed separately, the average fraction of changes was 0.126+/-0.113 and 0.161+/-0.120, respectively. Tumors lacking a ras mutation showed an increased GDF, primarily because of a higher fraction of gains. Tumors that were at advanced Dukes' stages and that were poorly differentiated also displayed a higher GDF. Finally, disease-free survival was significantly diminished in tumors with a GDF greater than 0.314 (P < .001). The prognostic significance of the GDF was independent of Dukes' stage (Cox multivariate analysis, P = .005). CONCLUSION: The degree of genomic damage assessed by unbiased DNA fingerprinting correlates with genotypic, phenotypic, and clinical variables in colorectal carcinoma and may be useful in assessing prognosis in colorectal cancer.

Aged↗

No evidence for association between IDDMK(1,2)22, a novel isolated retrovirus, and IDDM.

In the past, endogenous retroviral sequences have been isolated from patients suffering from different kinds of autoimmune diseases. Recently, a full length retroviral genome, termed IDDMK(1,2)22, was isolated from patients with new-onset IDDM. This genome contains a major histocompatibility complex II-dependent superantigen within its envelope gene. The viral sequence was found in ten patients with new-onset IDDM, but not in age-matched control subjects (Conrad et al. [9]). We searched for the presence of this viral genome by nested reverse transcription-polymerase chain reaction (RT-PCR) in a cohort of six patients with new-onset IDDM and six control subjects of the same age. We found all samples to be positive without any differences between patients and control subjects. The same results were obtained with supernatants of activated peripheral blood mononuclear cells. We performed isopycnic ultracentrifugation in sucrose density gradients on all samples and were unable to detect particles of the new virus in any of our samples. However, positive signals were obtained from all pellet fractions. RNase, DNase treatment and nested PCRs without reverse transcription showed that the positive signals were probably derived from intracellular RNA and DNA. In summary, no correlation between a positive nested PCR signal for IDDMK(1,2)22 and diabetes was found indicating that the new sequence represents just an additional member of the human endogenous retrovirus (HERV) family with lack of an exogenous counterpart.

Adult↗

[A study of gene therapy for beta-thalassemia. I. Retroviral-mediated transfer of human beta-globin gene into Friend cells].

We used a replication-defective retrovirus vector containing the human beta-globin gene to transfect the ecotropic packaging cell line psi-2, and then harvested the virus supernatant to infect the amphotropic packaging cell line PA317. As a result, a recombinant vector producing cell line (PIW beta) with a titer of 1.1 x 10(5) CFU/ml was isolated. By infecting Friend cells with this high titer virus vector, high efficiency gene transfer was achieved. Southern blot hybridization analysis indicated that the intact human beta-globin gene was stably integrated into the genome of the target cells. Our results provide a useful reference for further studies of gene therapy of beta-thalassemia.

Blotting, Southern↗

[Mixed type-II cryoglobulinemia associated with a chronic hepatitis C virus infection].

We describe the case of a patient with non A-non B post-transfusional cirrhosis and type-II mixed cryoglobulinemia, who showed in relation with said processes several acute symptoms of vasculitis, polyarthritis, pericarditis and autoimmune hemolytic anemia, finally dying due to an advanced hepatocellular insufficiency. In this patient the determination of antibodies against hepatitis C virus (anti-HCV) was positive, that is why we assume a possible relationship between both processes and the first literature references, after the clonation of the hepatitis C virus (HCV) genome, are reviewed.

Chronic Disease↗