bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beta‐cell dysfunctions and insulin resistance in subjects with increased risk for type 2 diabetes mellitus
Authors: Lichiardopol R. , Mirodon Zenaida 
Published: May 2007

AbstractThe aim of this study was to test if a beta‐cell defect is associated to deterioration of glucose tolerance early during the natural history of the type 2 diabetes mellitus. In 41 overweight women, with macrosomic infants in their antecedent deliveries, measures of insulin response and insulin sensitivity were derived from a short (45 min) iv glucose test. The early (EIR) and the late (LIR) phase insulin responses and the insulin sensitivity index (Si) were calculated. According the response to 75 g oral glucose test the subjects were divided into two groups: Imparired glucose tolerance (IGT;n = 12), and normal glucose tolerance (NGT; n = 29). EIR was reduced in IGT group (14.9 ± 3.6 vs 37.0 ± 4.0; p< 0.002). Glucose tolerance during oral glucose tolerance test (OGTT), correlated inversly to EIR (r=‐0.45; n=41; p< 0.01). A strong correlation of EIR to LIR (r=0.88; n = 41; p< 0.001) but no correlation between glucose tolerance and Si was found.
Apoptosis in human embryo development: 1. Cerebral cortex
Authors: Voiculescu B. , Nat Roxana , Lin Elisa , Iosef Cristiana 
Published: May 2007

AbstractWe investigated the apoptosis at the beginning of human cerebral cortex development, in the 6th week of embryogenesis, Carnegie stages 16 and 17. Attention was focused on the dorsal wall of the telencephalon to the ventricular zone of proliferation and to the postmitotic zone with beginning of neuronal migration. We identified apoptotic cells in tissue sections by propidium iodide staining, TUNEL and immunohistochemistry for Fas(APO‐1/CD95). We determined the distribution and the percentage (reported to the propidium iodide stained nuclei) of apoptotic TUNEL‐positive and Fas(APO‐1/CD95)‐positive cells. TUNEL‐positive apoptotic cells in the proliferative zone were 20% in stage 16 and 60% in stage 17. TUNEL‐positive apoptotic cells in the postmitotic zone were 8% in stage 16 and 30% in stage 17. CD95‐positive apoptotic cells in the proliferative zone were 5% in stage 16 and 2% in stage 17. There were no CD95‐positive cells in the postmitotic zone. We evidentiated the presence of the suicide receptor Fas(APO‐1/CD95) only on a small population of apoptotic neuroblasts in the proliferative zone. The differences between apoptotic distribution and receptors in early corticogenesis suggest that different apoptotic pathways drive the selection of neuronal populations.
Merosin‐deficient congenital muscular dystrophy: neuropathology case reports
Authors: Manole Emilia , Alexianu Marilena 
Published: May 2007

AbstractThe aims of our study were: to present cases of congenital muscular dystrophy (CMD) with deficiency in merosin and the importance of immunohistochemistry in the diagnosis of merosin‐deficient CMD. In four years (1997‐2000), we found three patients with merosin‐deficient CMD, one of them having an unusual clinical and pathological manifestation of the disease. Muscle biopsies of gastrocnemius or quadriceps muscles were investigated. In addition with the conventional HE staining, indirect immunohistochemistry for merosin, dystrophin, utrophin and for the proteins of the dystrophin associated complex (α,β, γ‐ sarcoglycans; β‐dystroglycan) was performed on cryosections. The findings suggest that there is no correlation between the clinical and histological picture of the disease and the expression of merosin in skeletal muscles. The degree of muscle involvment (assessed by histology) is parallel with the clinical neuromotor deficiency, but not with expression of merosin, which can be absent even in mild cases. The clinical investigations as well as current morphological techniques, only together with immunohistochemistry can differentiate between merosin ‐ deficient CMD and other muscular dystrophy forms.
Genetic analysis of factor V Leiden in a family with history of thrombosis and venous leg ulcers
Authors: Procopciuc Lucia M. , Has C. , Drugan C. , Jebeleanu Gh. 
Published: May 2007

AbstractInherited resistance to activated protein C has been recognized as a major risk factor for thrombosis. The factor V Leiden mutation, which is detectable by molecular DNA techniques, is responsible for 95% of cases of activated protein C resistance. In our study one patient with venous leg ulcers from a family with a history of thrombosis showed factor V Leiden mutation. Genotypic analysis demonstrated that the patient was homozygous for factor V Leiden. All family members of the index subject showed the same abnormalities. Two were homozygous and 3 were heterozygous for factor V Leiden mutation. The polymerase chain reaction was used to amplify exon 10 of the factor V gene, followed by enzymatic digestion with MnlI for mutation detection. Patients with a family history of thrombosis and factor V Leiden have an increased risk of venous leg ulcers. Screening for factor V Leiden may be indicated in patients with venous leg ulcers and their family members.
Contribution of apoptotic cell death to renal injury
Authors: Ortiz Alberto , Lorz Corina , Justo Pilar , Catalán Marina P. , Egido Jesüs 
Published: May 2007

AbstractCell number abnormalities are frequent in renal diseases, and range from the hypercellularity of postinfectious glomerulonephritis to the cell depletion of chronic renal atrophy. Recent research has shown that apoptosis and its regulatory mechanisms contribute to cell number regulation in the kidney. The role of apoptosis ranges from induction to repair and progression of renal injury. Death ligands and receptors, such as TNF and FasL, proapoptotic and antiapoptotic Bcl‐2 family members and caspases have all been shown to participate in apoptosis regulation in the course of renal injury. These proteins represent potential therapeutic targets, which should be further explored.
Detection of human papillomavirus gene sequences in cell lines derived from laryngeal tumors
Authors: Mutiu A. , Alexiu Irina , Chivu Mihaela , Petica M. , Anton Gabriela , Bleotu Coralia , Diaconu Carmen , Popescu C. , Jucu V. , Cernescu C. 
Published: May 2007

AbstractThe role of Human Papillomaviruses (HPV) in laryngeal carcinomas has been studied with conflicting results. To evaluate the etiologic relationship between HPV infection and epithelial malignancy of the larynx we studied five laryngeal carcinoma cell lines obtained from patients undergoing surgery for laryngeal tumors. The paraffin embedded biopsy samples of the original tumor and different passages of the new established cell lines were investigated by PCR with consensus primers specific for HPV DNA. The findings indicate that HPV infection is associated with some larynx carcinomas. The positive association has been enhanced when a method of enrichment of epithelial cells from fresh tumor samples was used. All tumor cells enriched smears were positive for HPV DNA not only by PCR but also by in situ hybridization (ISH). Investigated by PCR, different passages of larynx tumor cell lines maintained expression of HPV DNA. At subsequent passages ISH gives constantly no signals suggesting a minimal amount of viral harbored sequences. In one cell line propagated more than 60 population doublings, the chromosomal frequency distribution shifted from modal number 46 at the 5th passage to 63 at the 60th passage. The mechanisms by which persistent HPV infection maintains continuous cell proliferation were discussed.
Localizing genes in Drosophila melanogaster polytene chromosomes by fluorescence in situ hybridization
Authors: Gavrila L. , Ecovoiu Al. Al. , Georgescu Laura Monica 
Published: May 2007

AbstractThis paper describes a method for the identification of single copy genes in Drosophila melanogaster polytene chromosomes, using fluorescence in situ hybridization (FISH). We demonstrate the detection of white (w), a gene previously mapped to 1‐1.5 region of the linkage map, and to 3C2 region of the cytogenetic map of X chromosome. Squash preparations of polytene chromosomes from salivary glands dissected out from third instar larvae of Drosophila melanogaster were denatured and subjected to hybridization with a digoxigenin labeled probe, corresponding to mini‐white gene. The preparations were then washed and incubated with antidigoxigenin‐fluorescein antibodies. After removal of the nonspecifically bound antibodies, the polytene chromosomes were counterstained with propidium iodide. Fluorescence microscopy revealed white locus in the X chromosome in a subterminal location, in agreement with the above mentioned maps. The protocol is efficient and adaptable for simultaneously multiple signal detection.
TRH synthesis in “mute” thyrotropinomas: cause‐effect or coincidence?
Authors: Badiu C. , Ham J. , Carnu Ruxandra , Coculescu M. 
Published: May 2007

AbstractIn the pathogenesis of thyrotropin (TSH) immunopositive pituitary adenomas, trigger mutagenetic events are well recognized. However, the way towards a clinical significant tumor is followed under the pressure of growth factors, among which the intrapituitary synthesis of releasing factors could bring a significant contribution. In this study, the production of thyrotropin releasing hormone (TRH) and beta TSH chain was evaluated at the mRNA level by in situ hybridization and end product level by immunohistochemistry, in 18 patients submitted to neurosurgery for pituitary macroadenomas. The hormonal sampling showed abnormal secretion for FSH in 5 and TSH in 4 patients. Seven cases were immunopositive for TSH, and expressed TSH β mRNA. All but one out of these expressed also TRH mRNA. FSH immunoreactivity was documented in 12/ 18, only one of these being negative for TRH mRNA. Paracrine TRH could contribute to the patogenesis of these “mute” adenomas.
The hyperlipemic hamster ‐ a model for testing the anti‐atherogenic effect of amlodipine
Authors: Sima Anca , Stancu Camelia , Constantinescu Elena , Ologeanu Laura , Simionescu Maya 
Published: May 2007

AbstractMale Golden Syrian hamsters were subjected to a hyperlipemic diet. At intervals ranging from 2 to 14 weeks, the animals were examined for changes in serum constituents and structural modifications of lesion‐prone areas: the cardiac valves, coronary arteries and aortic arch. Serum was characterized by a gradual increase in cholesterol, triglycerides and a decrease in total peroxyl‐radical trapping potential. The sequence of modifications of the endothelial cells, smooth muscle cells, and migrating plasma monocytes as well as of the extracellular matrix were established. Amlodipine treatment of hyperlipemic hamster was assessed. Amlodipine exhibited an athero‐protective effect, acting as antioxidant, reducing the LDL uptake by the vessel wall and consequently, limiting the size and extent of lesioned areas. The hyperlipemic hamster is a reliable model to unravel the cellular alterations leading to atheroma formation, and for testing the effect of drugs in this process.
Apotosis in human embryo development: 2. Cerebellum
Authors: Nat Roxana , Voiculescu B. , Stanciu Cristina , Vidulescu Cristina , Cergan R. , Badiu C. , Popescu L. M. 
Published: May 2007

AbstractWe analysed the spatial and temporal distribution of apoptosis in human cerebellum development, during embryonic and fetal periods. Cerebella excised from two human embryos (8 weeks old) and eight fetuses (12‐22 weeks old), were paraffin embedded and serially sectioned. Apoptotic cells were identified by propidium iodide staining, and TUNEL. In addition, immunohistochemistry for suicide receptor Fas(APO‐1/CD95) was performed. We determined the distribution and percentage of apoptotic cells as well as Fas(APO‐1/CD95)‐positive cells in different regions and stages of development. Apoptotic cells were seen in both proliferative zones and postmitotic regions along the migratory pathways as well as in the developing cerebellar cortex in all examined stages. The Fas(APO‐1/CD95) immunoreactivity was present in all examined stages in a small population of apoptotic cells: either neuroblasts or differentiated cells in postmitotic zones. These findings suggest that apoptosis drives the selection of the cells which are committed to differentiate during the early stages of cerebellar development. The differences between apoptotic cells distribution and Fas receptor expression suggest that cell selection is driven by different apoptotic pathways.
A chemical method to isolate hypothalamic nonapeptides by coupling cyst(e)in with bimane
Authors: Catrina S. B. , Coculescu M. , Andersson M. 
Published: May 2007

AbstractVasopressin, oxytocin as well as other active nonapeptides (vasotocin, etc) are difficult to isolate from tissues. Traditionally they were identified using cumbersome biological assays or immunoassays, commercially unavailable, and with some cross reactivity. Based on the fact that all these peptides have two Cysteins in their molecules we developed a simple, sensitive and specific method to detect them by HPLC after pre‐column fluorescent derivatization with monobromobimane (mBBr). The peptides were separated on a Vydac C18 column after reduction with Tris (2‐carboxyethyl) phosphine (TCEP) and derivatization with mBBr for 5 minutes in dark. Using this method we were able to detect specific peaks for arginine‐, lysine‐vasopressin, and vasotocin at levels as low as 10 pmol. The method can be used to detect other active peptides with cyst(e)ins in their molecule, as well.
Translational regulation in cell stress and apoptosis. Roles of the eIF4E binding proteins
Authors: Clemens M.J. 
Published: May 2007

AbstractSeveral mechanisms have been identified by which protein synthesis may be regulated during the response of mammalian cells to physiological stresses and conditions that induce apoptotic cell death (reviewed in Clemens et al., Cell Death and Differentiation 7, 603–615, 2000). Recent developments allow us to up‐date this analysis and in this article I concentrate on one particular aspect of this regulation that has not previously been reviewed in depth in relation to apoptosis, viz. the control of the initiation of protein synthesis by eukaryotic initiation factor eIF4E and the eIF4E binding proteins (4E‐BPs). Changes in the state of phosphorylation of the 4E‐BPs and in the extent of their association with eIF4E occur at an early stage in the response of cells to apoptotic inducers. The review discusses the mechanisms by which these events are regulated and the significance of the changes for the control of protein synthesis, cell proliferation and cell survival.
New concepts in radiation‐induced apoptosis: ‘premitotic apoptosis’ and ‘postmitotic apoptosis’
Authors: Shinomiya N. 
Published: May 2007

AbstractFormerly, the mechanisms responsible for the killing of cells by ionizing radiation were regarded as being divided into two distinct forms, interphase death and reproductive death. Since they were defined based on the classical radiobiological concepts using a clonogenic cell survival assay, biochemical and molecular biological mechanisms involved in the induction of radiation‐induced cell death were not fully understood in relation to the modes of cell death. Recent multidisciplinary approaches to cell death mechanism have revealed that radiation‐induced cell death is divided into several distinct pathways by the time course and cell‐cycle position, and that apoptotic cell death plays a key role in almost every mode of cell death. This review discusses the mechanisms of radiation‐induced apoptosis in relation to cellcycle progression and highlights a new concept of the mode of cell death: ‘premitotic apoptosis’ and ‘postmitotic apoptosis’. The former is a rapid apoptotic cell death associated with a prompt activation of caspase‐3, a key enzyme of intracellular signaling of apoptosis. Arapid execution of cell killing in premitotic apoptosis is presumably due to the prompt activation of a set of pre‐existed molecules following DNA damages. In contrast, the latter is a delayed apoptotic cell death after cell division, and unlike premitotic apoptosis, it neither requires a rapid activation of caspase‐3 nor is inhibited by a specific inhibitor, Ac‐DEVD‐CHO. A downregulation of anti‐apoptotic genes such as MAPK and Bcl‐2 may play a key role in this mode of cell death. Characterization of these two types of apoptotic cell death regarding the cell cycle regulation and intrcellular signaling will greatly help to understand the mechanisms of radiation‐induced apoptosis.
Quality control of gene expression in the nucleus
Authors: Custódio Noélia , Carmo‐Fonseca Maria 
Published: May 2007

AbstractProteins are responsible for most cellular and extra‐cellular functions. If altered, proteins can loose their normal activity and/or gain new properties. Either way the consequences may be deleterious for the cell and lead to disease at the organism level. Not surprisingly, eukaryotes have evolved mechanisms to recognize abnormal messenger RNAs and prevent them from producing faulty proteins. Protein‐encoding genes are transcribed in the nucleus by RNA polymerase II as precursor RNAs that undergo extensive processing before being translocated to the cytoplasm for translation by the ribosomes. This spatial and temporal separation between RNA and protein synthesis offers an immense opportunity for control and regulation. Here we review recent studies that are beginning to unravel how the coupling between transcription, processing and transport of mRNAs contributes to control the quality of gene expression in the nucleus.
Prevalence of virulence genes in Escherichia coli strains isolated from Romanian adult urinary tract infection cases
Authors: Usein Codruta‐Romanita , Damian Maria , Tatu‐Chitoiu Dorina , Capusa Cristina , Fagaras Rodica , Tudorache Daniela , Nica Maria , Le Bouguénec Chantal 
Published: May 2007

AbstractA total of 78 E. coli strains isolated from adults with different types of urinary tract infections were screened by polymerase chain reaction for prevalence of genetic regions coding for virulence factors. The targeted genetic determinants were those coding for type 1 fimbriae (fimH), pili associated with pyelonephritis (pap), S and F1C fimbriae (sfa and foc), afimbrial adhesins (afa), hemolysin (hly), cytotoxic necrotizing factor (cnf), aerobactin (aer). Among the studied strains, the prevalence of genes coding for fimbrial adhesive systems was 86 %, 36%, and 23% for fimH, pap, and sfa/foc, respectively. The operons coding for Afa afimbrial adhesins were identified in 14% of strains. The hly and cnf genes coding for toxins were amplified in 23% and 13% of strains, respectively. A prevalence of 54% was found for the aer gene. The various combinations of detected genes were designated as virulence patterns. The strains isolated from the hospitalized patients displayed a greater number of virulence genes and a diversity of gene associations compared to the strains isolated from the ambulatory subjects. A rapid assessment of the bacterial pathogenicity characteristics may contribute to a better medical approach of the patients with urinary tract infections.
Immunohistochemical features of paragangliomas
Authors: Pávai Z. , Orosz Zs. , Horváth Emoke , Seres‐Sturm L. , Jung J. 
Published: May 2007

AbstractImmunohistochemistry is part of the routine diagnosis of the neuroendocrine tumors. In our study, we included 52 paragangliomas with various localizations by routine histology and immunohistochemistry. In order to increase the diagnostic specificity, a complex immunohistochemistry panel has been performed consisting of Bcl‐2, Ki‐67, Bax and Pituitary Adenylate Cyclase‐Activating Peptide (PACAP), somatostatin, VIP and Calcitonin Gene Related Peptide (CGRP). After heat induced antigen retrieval, the immunostaining was performed by StreptABC using DAB as a chromogen. We were the first to demonstrate the presence of Bax and PACAP in paragangliomas. Some of the used markers are of prognostic value. The relationship between Bcl‐2 and Bax is decisive in generating the final response to the input apoptotic signals. The Ki‐67 antigen staining has gained wide acceptance in prognostic evaluation of other tumor types. We noted a small number of Ki‐67 positive cases, which signifies a low mitotic activity of these tumors and a relatively high number of Bax positivities (32.9%) and the much lower number of Bcl‐2 positivities (11.39%), and could explain the benign behaviour of paragangliomas.
Altered mucin expression in the gastrointestinal tract: a review
Authors: Jass J. R. , Walsh M. D. 
Published: May 2007

AbstractEarly studies of changes in mucin expression in disorders of the gastrointestinal tract focused on alterations in the carbohydrate chain. This review briefly considers the various mechanisms by which such alterations may come about: (a) normal variation, (b) sialic acid alterations, (c) defective assembly of carbohydrate side‐chains, (d) changed expression of core proteins and (e) epithelial metaplasia. The availability of monoclonal antibodies to mucin core proteins adds a new dimension to mucin histochemistry. It is now possible to offer explanations for traditional mucin histochemical findings on the basis of lineage‐specific patterns of mucin core protein expression. Changes in core protein expression are described in inflammatory, metaplastic and neoplastic disorders of the gastrointestinal tract. The possibility that mucin change could be important in the aetiology of some diseases such as ulcerative colitis and H. pylori gastritis is considered. It is more probable, however, that changes in mucin expression are secondary to reprogramming of cellular differentiation and altered cell turnover. As such they may serve as markers to explain pathogenesis and provide novel diagnostic and prognositc information.
Prion diseases: contribution of high‐resolution immunomorphology
Authors: Fournier J‐G. , Grigoriev V. 
Published: May 2007

AbstractThe transmisible spongiform encephalopathies or prion diseases are fatal neurological diseases that occur in animals and humans. They are characterized by the accumulation in the cerebral tissue of the abnormal form of prion protein (PrPsc) produced by a post‐translational event involving conformational change of its normal cellular counterpart (PrPc). In this short review, we present some results on the biology of prion proteins which have benefited from morphological approaches combining the electron microscopy techniques and the immunodetection methods. We discuss data concerning in particular the physiological function of the normal cellular prion prion (PrPc) which have allowed to open up new vistas on prion diseases, the biogenesis of amyloid plaque and the cellular site involved in the prion protein conversion process.
Statins: mechanism of action and effects
Authors: Stancu Camelia , Sima Anca 
Published: May 2007

AbstractThe beneficial effects of statins are the result of their capacity to reduce cholesterol biosyntesis, mainly in the liver, where they are selectively distributed, as well as to the modulation of lipid metabolism, derived from their effect of inhibition upon HMG‐CoA reductase. Statins have antiatherosclerotic effects, that positively correlate with the percent decrease in LDL cholesterol. In addition, they can exert antiatherosclerotic effects independently of their hypolipidemic action. Because the mevalonate metabolism generates a series of isoprenoids vital for different cellular functions, from cholesterol synthesis to the control of cell growth and differentiation, HMG‐CoA reductase inhibition has beneficial pleiotropic effects. Consequently, statins reduce significantly the incidence of coronary events, both in primary and secondary prevention, being the most efficient hypolipidemic compounds that have reduced the rate of mortality in coronary patients. Independent of their hypolipidemic properties, statins interfere with events involved in bone formation and impede tumor cell growth.