Aldehyde dehydrogenase gene superfamily: the 2000 update

Aldehyde dehydrogenase (ALDH) superfamily represents a group of NAD(P)(+)-dependent enzymes that catalyze the oxidation of a wide spectrum of endogenous and exogenous aldehydes. With the advent of megabase genome sequencing, the ALDH superfamily is expanding rapidly on many fronts. As expected, ALDH genes are found in virtually all genomes analyzed to date, indicating the importance of these enzymes in biological functions. Complete genome sequences of various species have revealed additional ALDH genes. As of July 2000, the ALDH superfamily consists of 331 distinct genes, of which eight are found in archaea, 165 in eubacteria, and 158 in eukaryota. The number of ALDH genes in some species with their genomes completely sequenced and annotated, Escherichia coli and Caenorhabditis elegans, ranges from 10 to 17. In the human genome, 17 functional genes and three pseudogenes have been identified to date. Divergent evolution, based on multiple alignment analysis of 86 eukaryotic ALDH amino-acid sequences, was the basis of the standardized ALDH gene nomenclature system (Pharmacogenetics 9: 421-434, 1999). Thus far, the eukaryotic ALDHs comprise 20 gene families. A complete list of all ALDH sequences known to date is presented here along with the evolution analysis of the eukaryotic ALDHs.     

Contribution of exfoliative cytology to the diagnosis of laryngeal lesions

OBJECTIVE: To estimate the diagnostic accuracy and reliability of exfoliative laryngeal cytology. STUDY DESIGN: Over three years (1996-1999) cytologic smears were obtained from clinically suspicious laryngeal lesions during laryngoscopy in a total of 31 selected patients (28 males and 3 females with an age range from 28-90 years). The cytologic diagnoses were analyzed and correlated with the histologic and final clinical diagnoses in 17 and 14 cases, respectively. Cytologic identification of the exact histologic type of the lesion was evaluated in 17 patients from whom both cytologic smears and biopsy material were obtained. RESULTS: The overall specificity was 100%, with no false positive diagnoses. The overall sensitivity was 93.3%, with one false negative cytologic diagnosis, in a case of non-Hodgkin's lymphoma. Cytohistologic correlation showed complete agreement between cytologic and histologic diagnoses in five of six benign lesions, in four cases of dysplasia and in six cases of squamous cell carcinoma. The overall diagnostic accuracy of cytology was 96.7% CONCLUSION: Exfoliative cytology by the smear technique is a reliable and accurate method in clinically suspected laryngeal lesions. Moreover, exfoliative cytology may be applied as the only alternative diagnostic method, especially in elderly patients with coexistent cardiorespiratory problems, when biopsy is not advisable or indicated.     

In vitro and in vivo properties of distinct populations of amniotic fluid mesenchymal progenitor cells

Human mesenchymal progenitor cells (MPCs) are considered to be of great promise for use in tissue repair and regenerative medicine. MPCs represent multipotent adherent cells, able to give rise to multiple mesenchymal lineages such as osteoblasts, adipocytes or chondrocytes. Recently, we identified and characterized human second trimester amniotic fluid (AF) as a novel source of MPCs. Herein, we found that early colonies of AF-MPCs consisted of two morphologically distinct adherent cell types, termed as spindle-shaped (SS) and round-shaped (RS). A detailed analysis of these two populations showed that SS-AF-MPCs expressed CD90 antigen in a higher level and exhibited a greater proliferation and differentiation potential. To characterize better the molecular identity of these two populations, we have generated a comparative proteomic map of SS-AF-MPCs and RS-AF-MPCs, identifying 25 differentially expressed proteins and 10 proteins uniquely expressed in RS-AF-MPCs. Furthermore, SS-AF-MPCs exhibited significantly higher migration ability on extracellular matrices, such as fibronectin and laminin in vitro, compared to RS-AF-MPCs and thus we further evaluated SS-AF-MPCs for potential use as therapeutic tools in vivo. Therefore, we tested whether GFP-lentiviral transduced SS-AF-MPCs retained their stem cell identity, proliferation and differentiation potential. GFP-SS-AF-MPCs were then successfully delivered into immunosuppressed mice, distributed in different tissues and survived longterm in vivo. In summary, these results demonstrated that AF-MPCs consisted of at least two different MPC populations. In addition, SS-AF-MPCs, isolated based on their colony morphology and CD90 expression, represented the only MPC population that can be expanded easily in culture and used as an efficient tool for future in vivo therapeutic applications.     

Modulation of the CD95-induced apoptosis: the role of CD95 N-glycosylation

Protein modifications of death receptor pathways play a central role in the regulation of apoptosis. It has been demonstrated that O-glycosylation of TRAIL-receptor (R) is essential for sensitivity and resistance towards TRAIL-mediated apoptosis. In this study we ask whether and how glycosylation of CD95 (Fas/APO-1), another death receptor, influences DISC formation and procaspase-8 activation at the CD95 DISC and thereby the onset of apoptosis. We concentrated on N-glycostructure since O-glycosylation of CD95 was not found. We applied different approaches to analyze the role of CD95 N-glycosylation on the signal transduction: in silico modeling of CD95 DISC, generation of CD95 glycosylation mutants (at N136 and N118), modulation of N-glycosylation by deoxymannojirimycin (DMM) and sialidase from Vibrio cholerae (VCN). We demonstrate that N-deglycosylation of CD95 does not block DISC formation and results only in the reduction of the procaspase-8 activation at the DISC. These findings are important for the better understanding of CD95 apoptosis regulation and reveal differences between apoptotic signaling pathways of the TRAIL and CD95 systems.     

UK emissions of the greenhouse gas nitrous oxide

Signatories of the Kyoto Protocol are obliged to submit annual accounts of their anthropogenic greenhouse gas emissions, which include nitrous oxide (N(2)O). Emissions from the sectors industry (3.8 Gg), energy (14.4 Gg), agriculture (86.8 Gg), wastewater (4.4 Gg), land use, land-use change and forestry (2.1 Gg) can be calculated by multiplying activity data (i.e. amount of fertilizer applied, animal numbers) with simple emission factors (Tier 1 approach), which are generally applied across wide geographical regions. The agricultural sector is the largest anthropogenic source of N(2)O in many countries and responsible for 75 per cent of UK N(2)O emissions. Microbial N(2)O production in nitrogen-fertilized soils (27.6 Gg), nitrogen-enriched waters (24.2 Gg) and manure storage systems (6.4 Gg) dominate agricultural emission budgets. For the agricultural sector, the Tier 1 emission factor approach is too simplistic to reflect local variations in climate, ecosystems and management, and is unable to take into account some of the mitigation strategies applied. This paper reviews deviations of observed emissions from those calculated using the simple emission factor approach for all anthropogenic sectors, briefly discusses the need to adopt specific emission factors that reflect regional variability in climate, soil type and management, and explains how bottom-up emission inventories can be verified by top-down modelling.     

Biomarkers of protein oxidation in human disease

Oxidative stress is caused by an imbalance between the production of reactive species of oxygen and nitrogen (RS) and the ability to either detoxify the reactive intermediates produced or repair the resulting damage. Ultimately, oxidative stress conveys the alteration in cellular function caused by the reaction of RS with cellular constituents. Oxidative stress has been extensively reported to participate in the progression of a variety of human diseases including cancer, neurodegenerative disorders and diabetes. Oxidation of proteins is thought to be one of the major mechanisms by which oxidative stress is integrated into cellular signal transduction pathways. Thus, recent research efforts have been aimed to identify the role of specific oxidative protein modifications in the signal transduction events mediating the etiology of human diseases progression. The identification of these oxidative modifications has also raised the possibility of using this knowledge to develop new methods to diagnose diseases before they are clinically evident. In this work, we summarize the mechanisms by which RS generate distinct oxidative modifications. Furthermore, we also review the potential of these oxidative modifications to be used as early biomarkers of human disease.     

Purification of apolipoprotein H (beta 2-glycoprotein I)-like protein from human follicular fluid

We purified a glycoprotein of molecular weight 50 kDa that has an N-terminal sequence similar to that of apolipoprotein H indicating that it is identical to or highly homologous to apolipoprotein H. There are indications that apolipoprotein H or its homologue may be involved in the fertilization process. Sperm motion was assessed employing computer-assisted semen analysis. The addition of the purified protein to prepared sperm samples from normospermic men increases significantly the straight line velocity (VSL) and the amplitude of lateral head displacement (ALH) but does not increase the number of progressively motile sperm.     

Breast metastasis from uterine leiomyosarcoma diagnosed by fine needle aspiration: a case report

BACKGROUND: Leiomyosarcomas of the breast are a rare subgroup of primary breast sarcomas. Even more rare is breast metastasis of an extramammary leiomyosarcoma. To date, only 4 cases have been reported in the literature. CASE: We report a case of breast metastatic leiomyosarcoma in a 58-year-old woman with a prior history of uterine leiomyosarcoma, resected 18 months earlier. The breast mass was palpable and a fine needle aspiration (FNA) was performed. The microscopic examination showed cellular smears composed of loosely structured clusters and tissue fragments of spindle-shaped and polygonal or rounded malignant cells in disorderly arrangement. The tumor cells were medium- or large-sized, with basophilic cytoplasm and enlarged, irregular, hyperchromatic nuclei with nucleoli. Tumor giant cells and multinucleation were also present. The morphologic features along with immunocytochemical positivity for desmin, muscle-specific actin and vimentin indicated the diagnosis of a metastatic leiomyosarcoma. CONCLUSION: FNA cytology can be a reliable method for the diagnosis of leiomyosarcoma. The morphologic criteria in combination Swith the clinical history and the immunocytochemical findings can indicate a definitive diagnosis and avoid additional painful and time-consuming diagnostic procedures for the appropriate patient's further clinical management.     

Predicting post-synaptic activity in proteins with data mining

The bioinformatics problem being addressed in this paper is to predict whether or not a protein has post-synaptic activity. This problem is of great intrinsic interest because proteins with post-synaptic activities are connected with functioning of the nervous system. Indeed, many proteins having post-synaptic activity have been functionally characterized by biochemical, immunological and proteomic exercises. They represent a wide variety of proteins with functions in extracellular signal reception and propagation through intracellular apparatuses, cell adhesion molecules and scaffolding proteins that link them in a web. The challenge is to automatically discover features of the primary sequences of proteins that typically occur in proteins with post-synaptic activity but rarely (or never) occur in proteins without post-synaptic activity, and vice-versa. In this context, we used data mining to automatically discover classification rules that predict whether or not a protein has post-synaptic activity. The discovered rules were analysed with respect to their predictive accuracy (generalization ability) and with respect to their interestingness to biologists (in the sense of representing novel, unexpected knowledge).