bluuebunny/crossref_metadata_2025 huggingface dataset:
MYCL1, FHIT, SPARC, p16INK4 and TP53 genes associated to lung cancer in idiopathic pulmonary fibrosis
Authors: Demopoulos K. , Arvanitis D. A. , Vassilakis D. A. , Siafakas N. M. , Spandidos D. A.
Published: May 2007

Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic interstitial pneumonia limited to the lung and characterized by a fibroproliferative response with only minor signs of inflammation, which almost always causes rapid fibrotic destruction of the lung. In this study, we investigated genomic instability in IPF, using microsatellite DNA analysis, aiming to detect any specific genetic alterations for this disease. We used 40 highly polymorphic microsatellite DNA markers, in multiplex PCR assays, to examine 52 sputum specimens from IPF patients versus correspondent venous blood. Loss of heterozygosity (LOH) was found in 20 (38.5%) patients in at least one locus. These alterations were found on markers previously associated with lung cancer located on 1p34.3, 3p21.32‐p21.1, 5q32‐q33.1, 9p21 and 17p13.1 where MYCL1, FHIT, SPARC, p16Ink4 and TP53 genes have been mapped respectively. These data provide new insights into IPF pathogenesis and a new perspective for its correlation with lung cancer.
Few cultured rat primary sensory neurons express a tolbutamide‐sensitive K+ current
Authors: Ristoiu Violeta , Pluteanu Florentina , Flonta Maria‐Luiza , Reid G.
Published: May 2007

The response of dorsal root ganglion (DRG) neurons to metabolic inhibition is known to involve calcium‐activated K+ channels; in most neuronal types ATP‐sensitive K+ channels (KATP) also contribute, but this is not yet established in the DRG. We have investigated the presence of a KATP current using whole‐cell recordings from rat DRG neurons, classifying the neurons functionally by their “current signature” (Petruska et al, J Neurophysiol 84: 2365–2379, 2000). We clearly identified a KATP current in only 1 out of 62 neurons, probably a nociceptor. The current was activated by cyanide (2 mM NaCN) and was sensitive to 100 μM tolbutamide; the relation between reversal potential and external K+ concentration indicated it was a K+ current. In a further two neurons, cyanide activated a K+ current that was only partially blocked by tolbutamide, which may also be an atypical KATP current. We conclude that KATP channels are expressed in normal DRG, but in very few neurons and only in nociceptors.
Conversion of nucleotides sequences into genomic signals
Authors: Cristea P. D.
Published: May 2007

An original tetrahedral representation of the Genetic Code (GC) that better describes its structure, degeneration and evolution trends is defined. The possibility to reduce the dimension of the representation by projecting the GC tetrahedron on an adequately oriented plane is also analyzed, leading to some equivalent complex representations of the GC. On these bases, optimal symbolic‐to‐digital mappings of the linear, nucleic acid strands into real or complex genomic signals are derived at nucleotide, codon and amino acid levels. By converting the sequences of nucleotides and polypeptides into digital genomic signals, this approach offers the possibility to use a large variety of signal processing methods for their handling and analysis. It is also shown that some essential features of the nucleotide sequences can be better extracted using this representation. Specifically, the paper reports for the first time the existence of a global helicoidal wrapping of the complex representations of the bases along DNA sequences, a large scale trend of genomic signals. New tools for genomic signal analysis, including the use of phase, aggregated phase, unwrapped phase, sequence path, stem representation of components’relative frequencies, as well as analysis of the transitions are introduced at the nucleotide, codon and amino acid levels, and in a multiresolution approach.
Thrombospondin‐1 as an endogenous inhibitor of angiogenesis and tumor growth
Authors: Lawler Jack
Published: May 2007

Thrombospondin‐1 (TSP‐1) is a matricellular glycoprotein that influences cellular phenotype and the structure of the extracellular matrix. These effects are important components of the tissue remodeling that is associated with angiogenesis and neoplasia. The genetic mutations in oncogenes and tumor suppressor genes that occur within tumor cells are frequently associated with decreased expression of TSP‐1. However, the TSP‐1 that is produced by stromal fibroblasts, endothelial cells and immune cells suppresses tumor progression. TSP‐1 inhibits angiogenesis through direct effects on endothelial cell migration and survival and through indirect effects on growth factor mobilization. TSP‐1 that is present in the tumor microenvironment also acts to suppress tumor cell growth through activation of transforming growth factor β in those tumor cells that are responsive to TGFβ. In this review, the molecular basis for the role of TSP‐1 in the inhibition of tumor growth and angiogenesis is summarized.
Myocardial changes after spironolactone in spontaneous hypertensive rats. A laser scanning confocal microscopy study1
Authors: Pereira Leila Maria Meirelles , Mandarim‐de‐Lacerda C.A.
Published: May 2007

The present study aims to objectivate by laser scanning confocal microscopy, the cardiac structure of the spontaneously hypertensive rats (SHR) treated with different doses of spironolactone, either alone or in combination with an angiotensin converting enzyme inhibitor or with a calcium channel blocker. Thirty SHRs were divided into six groups and treated during 13 weeks as follows: control, spironolactone (5, 10 and 30 mg/kg/day), spironolactone + enalapril and spironolactone + verapamil. Spironolactone action on the SHR blood pressure (BP) was doses‐dependent. The cardiac hypertrophy was affected by the treatment with spironolactone (high dose) or a combination of spironolactone and Enalapril. The myocardial structure was less affected by the spironolactone monotherapy (at all doses) showing hypertrophied cardiac myocytes, focal areas of the reactive fibrosis, inflammatory infiltrate. The treatment with spironolactone in combination with enalapril or verapmil prevented these alterations. In conclusion, the monotherapy with spironolactone had only a limited effect in the preservation of the myocardial structure and in the attenuation of the interstitial fibrosis in SHRs, even after high dose. This action on the myocardium is more efficient when the spironolactone (even in medium dose) was associated with enalapril or verapamil.
Kinetics of apoptotic markers in exogeneously induced apoptosis of EL4 cells
Authors: Jessel Robert , Haertel Steffen , Socaciu Carmen , Tykhonova Svetlana , Diehl Horst A.
Published: May 2007

We investigated the time‐dependence of apoptotic events in EL4 cells by monitoring plasma membrane changes in correlation to DNA fragmentation and cell shrinkage. We applied three apoptosis inducers (staurosporine, tubericidine and X‐rays) and we looked at various markers to follow the early‐to‐late apoptotic events: phospholipid translocation (identified through annexin V‐fluorescein assay and propidium iodide), lipid package (via merocyanine assay), membrane fluidity and anisotropy (via fluorescent measurements), DNA fragmentation by the fluorescence‐labeling test and cell size measurements. The different apoptotic inducers caused different reactions of the cells: staurosporine induced apoptosis most rapidly in a high number of cells, tubercidine triggered apoptosis only in the S phase cells, while X‐rays caused a G2/M arrest and subsequently apoptosis. Loss of lipid asymmetry is promptly detectable after one hour of incubation time. The phosphatidylserine translocation, decrease of lipid package and anisotropy, and the increase of membrane fluidity appeared to be based on the same process of lipid asymmetry loss. Therefore, the DNA fragmentation and the cell shrinkage appear to be parallel and independent processes running on different time scales but which are kinetically inter‐related. The results indicate different signal steps to apoptosis dependent on inducer characteristics but the kinetics of “early‐to‐late” apoptosis appears to be a fixed program.
Molecular, immunological and clinical properties of mutated hepatitis B viruses
Authors: Kreutz C.
Published: May 2007

Hepatitis B virus (HBV) is at the origin of severe liver diseases like chronic active hepatitis, liver cirrhosis and hepatocellular carcinoma. There are some groups of patients with high risk of generation of HBV mutants: infected infants, immunosupressed individuals (including hemodialysis patients), patients treated with interferon and lamivudine for chronic HBV infection. These groups are the target for molecular investigations reviewed in this paper. The emergence of lamivudine‐ or other antiviral‐resistant variants, rises concern regarding long term use of these drugs. Infection or immunization with one HBV subtype confers immunity to all subtypes. However, reinfection or reactivation of latent HBV infection with HBV mutants have been reported in patients undergoing transplant and those infected with HIV. Mutations of the viral genome which are not replicative incompetent can be selected in further course of infection or under prolonged antiviral treatment and might maintain the liver disease. Four open reading frames (ORF) which are called S‐gene, C‐gene, X‐gene and P‐gene were identified within the HBV genome. Mutations may affect each of the ORFs. Mutated S‐genes were described to be responsible for HBV‐infections in successfully vaccinated persons, mutated C‐genes were found to provoke severe chronic liver diseases, mutated X‐genes could cause serious medical problemes in blood donors by escaping the conventional test systems and mutated P‐genes were considered to be the reason for chemotherapeutic drug resistance. This paper reviews molecular, immunological and clinical aspects of the HBV mutants.
Sarcolemmal and mitochondrial KATP channels and myocardial ischemic preconditioning
Authors: Peart J. N. , Gross G. J.
Published: May 2007

Ischemic preconditioning (IPC) is the phenomenon whereby brief periods of ischemia have been shown to protect the myocardium against a sustained ischemic insult. The result of IPC may be manifest as a marked reduction in infarct size, myocardial stunning, or incidence of arrhythmias. While many substances and pathways have been proposed to play a role in the signal transduction mediating the cardioprotective effect of IPC, overwhelming evidence indicates an intimate involvement of the ATP‐sensitive potassium channel (KATP channel) in this process. Initial hypotheses suggested that the surface or sarcolemmal KATP (sarcKATP) channel mediated the cardioprotective effects of IPC. However, much research has subsequently supported a major role for the mitochondrial KATP channel (mitoKATP) as the one involved in IPC‐mediated cardioprotection. This review presents evidence to support a role for the sarcKATP or the mitoKATP channel as either triggers and/or downstream mediators in the phenomenon of IPC.
Designing of ‘intelligent’ liposomes for efficient delivery of drugs
Authors: Voinea Manuela , Simionescu Maya
Published: May 2007

The liposome‐ vesicles made by a double phospholipidic layers which may encapsulate aqueous solutions‐ have been introduced as drug delivery vehicles due to their structural flexibility in size, composition and bilayer fluidity as well as their ability to incorporate a large variety of both hydrophilic and hydrophobic compounds. With time the liposome formulations have been perfected so as to serve certain purposes and this lead to the design of “intelligent” liposomes which can stand specifically induced modifications of the bilayers or can be surfaced with different ligands that guide them to the specific target sites. We present here a brief overview of the current strategies in the design of liposomes as drug delivery carriers and the medical applications of liposomes in humans.
Neural stem cells in aging and disease
Authors: Limke T. L. , Rao Mahendra S.
Published: May 2007

Aging in the central nervous system is associated with progressive loss of function which is exacerbated by neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. The two primary cell replacement strategies involve transplantation of exogenous tissue, and activation of proliferation of endogenous cells. Transplanted tissue is used to either directly replace lost tissue, or to implant genetically engineered cells that secrete factors which promote survival and/or proliferation. However, successful application of any cell replacement therapy requires knowledge of the complex relationships between neural stem cells and the more restricted neural and glial progenitor cells. This review focuses on recent advances in the field of stem cell biology of the central nervous system, with an emphasis on cellular and molecular approaches to replacing cells lost in neurodegenerative disorders.
Reactive oxygen species, antioxidant mechanisms and serum cytokine levels in cancer patients: impact of an antioxidant treatment
Authors: Mantovani G. , Macciò A. , Madeddu C. , Mura L. , Massa E. , Gramignano G. , Lusso M. R. , Murgia V. , Camboni P. , Ferreli L.
Published: May 2007

Objective. So far, it is not well established whether oxidative stress found in cancer patients results from an increased production of oxidants in the body or from a failure of physiological antioxidant systems. To further investigate this question we have assessed the blood levels of reactive oxygen species as a marker of free radicals producing oxidative stress and the most relevant of the physiological body enzymes counteracting reactive oxygen species, namely glutathione peroxidase and superoxide dismutase. Serum levels of proinflammatory cytokines and IL‐2 were also investigated. All these parameters were studied in relation to the clinically most important index of disease progression, namely Performance Status (ECOG PS). We also tested the reducing ability of different antioxidant agents on reactive oxygen species levels by measuring the increase in glutathione peroxidase activity, and the reduction of serum levels of IL‐6 and TNF. Design, setting and subjects. We carried out an open non randomized study on 28 advanced stage cancer patients (stage III, 10.7%, and stage IV, 89.3%) with tumours at different (8) sites: all were hospitalized in the Medical Oncology Dept, University of Cagliari Interventions. The patients were divided into 5 groups and a different antioxidant treatment was administered to each group. The selected antioxidants were: alpha lipoic acid 200 mg/day orally, N‐acetylcysteine 1800 mg/day i.v. or carboxycysteine‐lysine salt 2.7 g/day orally, amifostine 375 mg/day i.v., reduced glutathione 600 mg/day i.v., vitamin A 30000 IU/day orally plus vitamin E 70 mg/day orally plus Vitamin C 500 mg/day orally. The antioxidant treatment was administered for 10 consecutive days. Results. Our results show that all but one of the antioxidants tested were effective in reducing reactive oxygen species levels and 2 of them (cysteine‐containing compounds and amifostine) had the additional effect of increasing glutathione peroxidase activity. Comprehensively, the “antioxidant treatment” was found to have an effect both on reactive oxygen species levels and glutathione peroxidase activity. The antioxidant treatment also reduced serum levels of IL‐6 and TNF. Patients in both ECOG PS 0‐1 and ECOG PS 2‐3 responded to antioxidant treatment.
Blood histamine is associated with coronary artery disease, cardiac events and severity of inflammation and atherosclerosis
Authors: Clejan Sanda , Japa Shenkar , Clemetson C. , Hasabnis Sanjeev S. , David Odile , Talano J. V.
Published: May 2007

Background: Mast cells are prevalent in the shoulder of unstable atheromas; cardiac mast cells secrete proteases capable of activating matrix metalloproteinases. Histamine is essential in the inflammatory cascade of the unstable plaque. Ascorbate depletion has been correlated with histaminemia which has been shown to impair endothelial‐dependent vasodilation. This study evaluates whether oxidative stress as measured by isoprostanes (PGF2α) coupled with an inflammatory state characterized by histaminemia predisposes patients to acute coronary syndrome (ACS).

Methods: Whole blood histamine, serum vitamin C, and serum PGF2α levels were drawn on 50 patients with ACS as determined by standard diagnostic criteria, 50 patients with stable coronary artery disease (SCAD), and 50 age and sex matched normal controls (C).

Results: Data were analyzed by stepwise discriminant and Spearman's rank correlation coefficient. A significant relationship exists between histamine and PGF2α. As PGF2α rises above 60 pg/mL, an increase in histamine occurs in both the ACS and SCAD groups. A significant inverse relationship exists between ascorbate and histamine in the ACS versus C groups (P < 0.01) and the SCAD versus C groups (P < 0.01).

Conclusion: Histamine and isoprostane levels increase in SCAD and ACS patients. Mast cell activation and lipid oxidation generated during atherosclerosis manifest this inflammatory response. Accelerated isoprostane formation and depleted ascorbate paired with histaminemia is active in CAD and predispose patients to acute coronary syndrome. Blood histamine alone may be a better risk factor for coronary events, and a better prognostic indicator than CRP even when combined with lipid indexes.
Stem cells (p63+) in keratinocyte cultures from human adult skin
Authors: Radu E. , Siminoescu Olga , Regalia T. , Dumitrescu Doina , Popescu L. M.
Published: May 2007

Epidermal stem cells (ESC) are responsible for maintaining skin cellular homeostasis, as they give rise to fast‐dividing transit amplifying cells committed to terminal differentiation, while retaining their self‐renewal capacity. However, no pure ESC cultures are available and no highly specific cytochemical marker was identified. We report here the experimental conditions allowing the selective enrichment in ESC, using cultured adult human keratinocytes. The main step was the selection of cells able to rapidly adhere to human collagen type IV in vitro. Thus, an increased proportion of putative ESC of about 65% was obtained, as demonstrated by p63 expression.
Beneficial effect of enalapril in spontaneously hypertensive rats cardiac remodeling with nitric oxide synthesis blockade
Authors: de Andrade Zorzi R. L. , Meirelles Pereira Leila M. , Mandarim‐de‐Lacerda C. A.
Published: May 2007

Aims. To study the efficiency of an angiotensin converting enzyme inhibitor on the blood pressure (BP) and the myocardium remodeling when spontaneously hypertensive rats (SHRs) are submitted to nitric oxide synthesis (NOs) blockade (with L‐NAME) and simultaneously treated.

Methods. Young adult male SHRs were separated in four groups (n = 5) and treated for 20 days: Control, L‐NAME, L‐NAME+Enalapril, and Enalapril. The alterations of the BP, heart mass/body mass ratio and stereological parameters for myocytes, connective tissue and intramyocardial vessels were studied among the groups.

Results. The SHRs with NOs blockade showed a great modification of the myocardium with extensive areas of reparative and interstitial fibrosis and accentuated hypertrophy of the cardiac myocytes (cross sectional area 60% higher in animals taking L‐NAME than in Control SHRs). Comparing the SHRs with NO deficiency (L‐NAME group), the Control SHRs and the Enalapril treated SHRs significant differences were found in the BP and in all stereological parameters. The NO deficiency caused an important BP increment in SHRs that was partially attenuated by Enalapril. This Enalapril effect was more pronounced in Control SHRs. A significant increment of the intramyocardial vessels was observed in NO deficient SHRs and Control SHRs treated with Enalapril demonstrated by the stereology (greater microvascular densities in treated SHRs).

Conclusion. Enalapril administration showed a beneficial effect on vascular remodeling and myocardial hypertrophy in SHRs. In SHRs with NO blockade, however, the beneficial effect of Enalapril occurred only in vascular remodeling.
Effect of ischemia‐reperfusion on the post‐rest inotropy of isolated perfused rat heart
Authors: Juggi J.S.
Published: May 2007

This paper aims to study of the effects of ischemia‐reperfusion on the post‐rest inotropy and to characterize post‐rest B1:B2 ratio as an index of intracellular Ca2+ overload. When the rest interval between the cardiac beats is increased, the magnitude of the post‐rest beats is increased. First beat (B1) is maximally potentiated with exponental decline of the second (B2) and subsequent beats, thereby establishing a normal B1:B2 ratio of post‐ rest inotropy of the cardiac muscle. The rest potentiation of B1 and subsequent decay in the magnitude B2 is thought to develop from the time‐dependent changes in the Ca2+‐uptake and release from the sarcoplasmic reticulum (SR). Ca2+‐kinetics of SR can be modulated by a variety of interventions which produce Ca2+ loading of the SR.

Methods: Isolated perfused (K‐H buffer, 34°C) rat hearts were paced at 1 Hz (steady state frequency). Interbeat intervals between 1s and 10s were introduced and the recovery in the left ventricular contractile force (Pmax) of post‐rest B1 and B2 for each interval was recorded. Their relative relationship was computed and compared under control and experimental conditions.

Results: High extracellular Ca2+ (2.50 to 7.0 mM) or low extracellular Na+ (50% of control), and ischemia (60 min, 34°C) ‐ reperfusion (30 min, 34°C) caused the reversal of the control relationship of the B1 to B2, with B2 being more potentiated than B1, accompanied by the appearance of after‐contractions during the rest intervals of 4s or more. The mean (± SE) control B1:B2 ratio (at 4s interval) of 1.12 ± 0.05 was significantly (P<0.001) reduced to 0.93 ± 0.07; 0.89 ± 0.01; and 0.96 ± 0.02 after high Ca2+ (6 mM) perfusion, low Na+(50%) perfusion and ischemia‐reperfusion respectively. Simultaneous perfusion with ryanodine (1 μM) abolished the after‐contractions and significantly increased the reduced ratios. The time course of changes in B1:B2 ratio after graded ischemia‐reperfusion showed a significant fall in the ratio between 30 and 60 min of ischemia. A parallel change in Pmax and a significant rise in the left ventricular end‐diastolic pressure, indicating an irreversible phase of the injury was recorded. No significant changes in B1:B2 ratio were detected during the reversible phase (<30 min) of the ischemia‐reperfusion injury.

Conclusions: Ischemia‐reperfusion induces significant alterations in the relative ratio of the post‐rest contractions of the left ventricle in isolated perfused rat heart. The altered ratios were characterized to predict the irreversibility of the reperfusion injury and to index the extent of Ca2+‐loading of the sarcoplasmic reticulum.
Highly effective techniques in computerized dental tissue morphometry
Authors: Caruntu Irina‐Draga
Published: May 2007

The effectiveness of computer‐aided morphometry is greatly dependent of the capabilities of the software platforms, but the literatutre provides only information about the measurement methods and thier medical interpretation. The purpose of our work is to create a link between the technical algorithm and the medical significance, by a detialed description of measurement procedures, accompained by the interpretation of thier results. The developmed techniques operate at a pixel level, by deriving a full benefit from the computational resources avilable in the modern software evnvironments for image processing. The approach is built on three illustrative cases, formulated in a large sense, so as to cover classes of general problems, referring to cellular entities and tubular structures in cross and longitudinal section. Specimens belonging to the dentin‐pulp complex were chosen, because they permit a quantitiative analysis for each morphological element, as well as comparative discussion. With appropriate adaptations of the procedures, the measurements of other types of normal and pathological tissues and be analogously addressd. The design, implementation and exploittion of our procedures are supported by specific references to the use of an image analysis system (Zeiss KS400). The algorithmic background remains valid (except for some possible minor changes) when similar software is used. Consequently, the results and thier interpretations, prove the importance of the numerical analysis in automating the quantitative evaluation of the structural features.
Angiogenesis and chemokines in rheumatoid arthritis and other systemic inflammatory rheumatic diseases
Authors: Bodolay Edit , Koch Alisa E. , Kim Joon , Szegedi Gyula , Szekanecz Zoltan
Published: May 2007

Angiogenesis, the formation of new vessels, is important in the pathogenesis of rheumatoid arthritis (RA) and other inflammatory diseases. Chemotactic cytokines termed chemokines mediate the ingress of leukocytes, including neutrophils and monocytes into the inflamed synovium. In this review, authors discuss the role of the most important angiogenic factors and angiogenesis inhibitors, as well as relevant chemokines and chemokine receptors involved in chronic inflammatory rheumatic diseases. RA was chosen as a prototype to discuss these issues, as the majority of studies on the role of angiogenesis and chemokines in inflammatory diseases were carried out in arthritis. However, other systemic inflammatory (autoimmune) diseases including systemic lupus erythematosus (SLE), systemic sclerosis (SSc), Sjögren's syndrome (SS), mixed connective tissue disease (MCTD), polymyositis/dermatomyositis (PM/DM) and systemic vasculites are also discussed in this context. As a number of chemokines may also play a role in neovascularizaton, this issue is also described here. Apart from discussing the pathogenic role of angiogenesis and chemokines, authors also review the regulation of angiogenesis and chemokine production by other inflammatory meditors, as well as the important relevance of neovascularization and chemokines for antirheumatic intervention.
Angiotensinogen gene M235T variant and pre‐eclampsia in Romanian pregnant women
Authors: Procopciuc Lucia , Jebeleanu Gh. , Surcel I. , Puscas M.
Published: May 2007

Background. Association between the human angiotensinogen gene and essential hypertension has been confirmed in recent studies. Pre‐eclampsia is a complication of pregnancy characterised by increased vascular resistance, high blood pressure, proteinuria and oedema, that appears in the second and third trimester of pregnancy. The aim of our study was the analysis of M235T mutation in the gene encoding angiotensinogen in Romanian women with different forms of hypertension during pregnancy. Methods. Fourteen women with obstetric complications were tested for M235T angiotensinogen gene mutation. Indications for testing were: severe or mild pre‐eclampsia and pre‐eclampsia associated with chronic hypertension. We also tested for control 6 healthy women. The M235T angiotensinogen gene mutation was analysed by polymerase chain reaction followed by enzymatic digestion with Tth 111I restriction endonuclease enzyme and agarose gel electrophoresis of the products. Results. Eleven (78.57%) of the 14 women with complications of pregnancy had M235T mutation: 9 (64.28%) were found to be heterozygous carriers of the M235T variant of the angiotensinogen gene and 2(14.28%) were found to be homozygous carriers. In the group of women with normal pregnancy, 3 (50%) of the 6 women had M235T mutation: 2 (33.33%) were found to be heterozygous carriers of the M235T variant of the angiotensinogen gene and 1 (16.66%) was found to be homozygous carrier. Conclusions. Our study shows that the M235T variant in the gene encoding angiotensinogen could be a risk factor in mild and severe pre‐eclampsia.
Oxidative stress in the pathogenesis of nonalcoholic fatty liver disease, in rats fed with a choline‐deficient diet
Authors: Oliveira Claudia P.M.S. , Da Costa Gayotto L. Carlos , Tatai Caroline , Della Bina Bianca Ishimoto , Janiszewski M. , Lima E.S. , Abdalla Dulcinéia S.P. , Lopasso F.P. , Laurindo F.R.M. , Laudanna A.A.
Published: May 2007

Background/Aim: The pathogenesis of Nonalcoholic Fatty Liver Disease remains largely unknown, but oxidative stress seems to be involved. The aim of this study was to evaluate the role of oxidative stress in experimental hepatic steatosis induced by a choline‐deficient diet.Methods: Fatty liver disease was induced in Wistar rats by a choline‐deficient diet. The animals were randomized into three groups: I (G1) and II (G2), n=6 each ‐ fed with a choline‐deficient diet for four and twelve weeks respectively; Group III (control‐G3; n=6) ‐ fed with a standard diet for twelve weeks. Samples of plasma and liver were submitted to biochemical, histological and oxidative stress analysis. Variables measured included serum levels of aminotransferases (AST, ALT), cholesterol and triglycerides. Oxidative stress was measured by lucigenin‐enhanced luminescence and the concentration of hydroperoxides (CE‐OOH‐cholesteryl ester) in the liver tissue. Results: We observed moderate macro‐ and microvesicular fatty change in periportal zones G1 and G2 as compared to controls (G3). In G2, fatty change was more severe. The inflammatory infiltrate was scanty and no fibrosis was seen in any group. There was a significant increase of AST and triglycerides in G1 and G2 as compared to control group G3. The lucigenin‐amplified luminescence (cpm/mg/min × 103) was significantly increased in G1 (1393±790) and G2 (7191±500) as compared to controls (513±170),p<0.05. The concentrations of CE‐OOH were higher in G1 (5.7±0.9 nmol/mg protein) as compared to control (2.6±0.7 nmol/mg protein),p<0.05. Conclusion: 1) Oxidative stress was found to be increased in experimental liver steatosis; 2) The production of reactive oxygen species was accentuated when liver steatosis was more severe; 3) The alterations produced by oxidative stress could be an important step in the pathogenesis of nonalcoholic fatty liver disease.
Tissue cultures from adult human postmortem subcortical brain areas
Authors: Verwer R.W.H. , Dubelaar E.J.G. , Hermens W.T.J.M.C. , Swaab D.F.
Published: May 2007

Animal models used to study human aging and neurodegeneration do not display all symptoms of these processes as they are found in humans. Recently, we have shown that many cells in neocortical slices from adult human postmortem brain may survive for extensive periods in vitro. Such cultures may enable us to study age and disease related processes directly in human brain tissue. Here, we present observations on subcortical brain tissue.
The role of fibroblast growth factor‐2 in the vascularization of the chick embryo chorioallantoic membrane
Authors: Ribatti D. , Presta M.
Published: May 2007

The CAM is an extraembryonic membrane which serves as a gas exchange surface and its respiratory function is provided by an extensive capillary network. The development of the vascular system of the CAM is a complex, highly regulated process that depends on genetic and epigenetic factors expressed by endothelial and non‐endothelial cells. In spite of the evidence that several growth factors are angiogenic in the CAM assay, poorly investigated is their role in the development of the CAM's vascular system. This article reviews our studies concerning the role of exogenous and endogenous fibroblast growth factor‐2 (FGF‐2) in the CAM vascularization. The findings in all these studies support the importance of FGF‐2 as an autocrine paracrine stimulator of angiogenesis and its key role in the development of the vascular system in the avian embryo.
Tetrathiomolybdate anticopper therapy for Wilson's disease inhibits angiogenesis, fibrosis and inflammation
Authors: Brewer G. J.
Published: May 2007

The need for agents to lower body copper in Wilson's disease, a disease which results from copper toxicity has been the driving force for the development of the effective anticopper drugs penicillamine, trientine, zinc, and now tetrathiomolybdate (TM). Because of its rapid action, potency, and safety, TM is proving to be a very effective drug for initial treatment of acutely ill Wilson's disease patients. Beyond this, TM has antiangiogenic effects, because many proangiogenic cytokines require normal levels of copper. This has led to use of TM in cancer, where it is generally effective in animal tumor models, and has shown efficacy in preliminary clinical studies. Most recently, it has been found that TM has antifibrotic and antiinflammatory effects through inhibition of profibrotic and proinflammatory cytokines.
Physiological and pathological roles of Apaf1 and the apoptosome
Authors: Ferraro E. , Corvaro M. , Cecconi F.
Published: May 2007

Different cellular pathways can lead to apoptosis. Apaf1 is the molecular core of the apoptosome, a multiproteic complex mediating the so‐called mitochondrial pathway of cell death. The importance of this pathway during development has been clearly demonstrated by knocking out key genes. Also, the relevance of Apaf1 dosage during development has been recently underlined. Moreover, a growing body of evidences seems to point out a possible role of the mitochondria‐dependent apoptosis in different pathologies. In particular, we discuss here some recent evidences regarding the putative role of the apoptosome in neurodegeneration and cancer.
RNA‐binding ability of PIPP in requires the entire protein
Authors: Raimondi Lavinia , D'Asaro Matilde , Proia Patrizia , Nastasi Tommaso , Di Liegro Italia
Published: May 2007

Post‐transcriptional fate of eukaryotic mRNAs depends on association with different classes of RNA‐binding proteins (RBPs). Among these proteins, the cold‐shock domain (CSD)‐containing proteins, also called Y‐box proteins, play a key role in controlling the recruitment of mRNA to the translational machinery, in response to environmental cues, both in development and in differentiated cells. We recently cloned a rat cDNA encoding a new CSD‐protein that we called PIPPin. This protein also contains two putative double‐stranded RNA‐binding motifs (PIP1 and PIP2) flanking the central CSD, and is able to bind mRNAs encoding H1° and H3.3 histone variants. In order to clarify the role of each domain in the RNA‐binding activity of PIPPin, we constructed a number of different recombinant vectors, encoding different regions of the protein. Here we report that only recombinant proteins that contain all the putative PIPPin domains show RNA‐binding ability.
Scrreening for microdeletions in human Y chromosome‐AZF candidate genes and male infertility
Authors: Raicu Florina , Popa L. , Apostol Pompilia , Cimpomeriu D. , Dan Letitia , Ilinca Elena , Dracea Laura Luana , Marinescu B. , Gavrila L.
Published: May 2007

About 30% of couple infertilities are of male origin, some of them caused by genetic abnormalities of the Y chromosome. Deletions in AZF region can cause severe spermatogenic defects ranging from non‐obstructive azoospermia to oligospermia. The intracytoplasmatic sperm injection technique (ICSI) is rapidly becoming a versatile procedure for human assisted reproduction in case of male infertility. The use of ICSI allows Y chromosome defects to be passed from father. The goal of our study is to evaluate the frequency of microdeletions in the long arm of Y chromosome, within the AZF regions, in these cases of infertilities, using molecular genetics techniques. Thirty infertile men with azoospermia or oligozoospermia, determined by spermogram, were studied after exclusion of patients with endocrine or obstructive causes of infertility. Peripheral blood DNA was extracted from each patient, then amplified by multiplex PCR with STS genomic markers from the Y chromosome AZF zones. Each case was checked by multiplex PCR through coamplification with the SRY marker. Three men with microdeletions of the long arm of the Y chromosome were diagnosed among the 30 patients, corresponding to a proportion of 10%. The relatively high proportion of microdeletions found in our population suggest the need for strict patient selection to avoid unnecessary screening for long arm Y chromosome microdeletions. The molecular diagnostics was performed according to the current European Academy of Andrology laboratory guidelines for molecular diagnosis of Y chromosomal microdeletions.
Glucose deprivation induces mitochondrial dysfunction and oxidative stress in PC12 cell line
Authors: Liu Yan , Song Xiao‐Dong , Liu Wen , Zhang Tian‐Yi , Zuo Ji
Published: May 2007

Glucose metabolism plays a pivotal role in many physiological and pathological conditions. To investigate the effect of hypoglycemia (obtained by glucose deprivation) on PC12 cell line, we analyzed the cell viability, mitochondrial function (assessed by MTT reduction, cellular ATP level, mitochondrial transmembrane potential), and the level of reactive oxygen species (ROS) after glucose deprivation (GD). Upon exposure to GD, ROS level increased and MTT reduction decreased immediately, intracellular ATP level increased in the first 3 hours, followed by progressive decrease till the end of GD treatment, and the mitochondrial transmembrane potential (ΔΨm) dropped after 6 hours. Both necrosis and apoptosis occurred apparently after 24 hours which was determined by nuclei staining with propidium iodide(PI) and Hoechst 33342. These data suggested that cytotoxity of GD is mainly due to ROS accumulation and ATP depletion in PC12 cells.
Imbalance of peripheral B lymphocytes and NK cells in rheumatoid arthritis
Authors: Manda Gina , Neagu Monica , Livescu Alexandra , Constantin Carolina , Codreanu C. , Radulescu Alina
Published: May 2007

The study was focused on several cellular immune disorders correlated with the imbalance between peripheral blood B lymphocytes and NK cells in severe rheumatoid arthritis. By flow cytometry we calculated the proportions of T, T helper, T cytotoxic/suppressor, B lymphocytes and natural killer cells in peripheral blood. The mitogen‐induced proliferation of peripheral lymphocytes was measured by tritium‐labeld uridine incorporation. Experimental data highlight a connection between annomal values of the B to natural killer cells ratio and disorders of the peripheral mononuclear cells concentration. We also showed that the polyclonal proliferation capacity of peripheral lymphocytes in rheumatoid arthritis is solely related to the B to natural killer cells ratio or to the natural killer cells proportion. The study reveals a potential role of the imbalance between proportions of peripheral B lymphocytes and natural killer cells in the immune pathogenesis of rheumatoid arthritis, thus pointing out an interrelation between the adaptive and innate immune systems.
Plasma 249Ser p53 mutation in patients with hepatocellular carcinoma residing in a high risk area
Authors: Dong‐Dong Lu , Xi‐Ran Zhang
Published: May 2007

Objective: To investigate plasma p53 mutation in hepatocellular carcinoma (HCC) patients from Qidong and to define its significance. Methods: Blood samples from 25 hepatocellular carcinoma patients, 20 cirrhotic patients and 30 healthy controls in Qidong area. DNA was extracted and purified from 200μl of plasma from each sample. The 249Ser p53 mutation was detected by restriction digestion analysis and by direct sequencing of exon‐7 PCR products. Results: G→T transversion at the third base of 249 codon resulting in 249Arg→249Ser mutation in exon 7 of p53 gene were found in 11/25(44%) hepatocellular carcinoma cases, 4/20 (20%) cirrhotics, and 2/30 (7%) healthy controls (p<0.01). Conclusions: These data show that the 249Ser p53 mutation in plasma is strongly associated with hepatocellular carcinoma patients in Qidong area and the mutation should be screened as a new early diagnostic marker for HCC.
Stemness, fusion and renewal of hematopoietic and embryonic stem cells
Authors: Constantinescu S.
Published: May 2007

Development of replacement cell therapies awaits the identification of factors that regulate nuclear reprogramming and the mechanisms that control stem cell renewal and differentiation. Once such factors and signals will begin to be elucidated, new technologies will have to be envisaged where uniform differentiation of adult or embryonic stem cells along one differentiation pathway can be induced. Controlled differentiation of stem cells will require the engineering of niches and extracellular signal combinations that would amplify a particular signaling network and allow uniform and selective differentiation. Three recent advances in stem cell research open the possibility to approach engineering studies for cell replacement therapies. Fusion events between stem cells and adult cells or between adult and embryonic stem cells have been shown to result in altered fates and nuclear reprogramming of cell hybrids. Hematopoietic stem cells were shown to require Wnt signaling in order to renew. The purification of Wnt proteins would allow their use as exogenous purified cytokines in attempts to amplify stem cells before bone marrow transplantation. The homeodomain protein Nanog has been shown to be crucial for the embryonic stem cell renewal and pluripotency. However, the cardinal question of how stemness is preserved in the early embryo and adult stem cells remains opened.
Polyamine metabolism and cancer
Authors: Thomas Thresia , Thomas T. J.
Published: May 2007

Polyamines are aliphatic cations present in all cells. In normal cells, polyamine levels are intricately controlled by biosynthetic and catabolic enzymes. The biosynthetic enzymes are ornithine decarboxylase, S‐adenosylmethionine decarboxylase, spermidine synthase, and spermine synthase. The catabolic enzymes include spermidine/spermine acetyltransferase, flavin containing polyamine oxidase, copper containing diamine oxidase, and possibly other amine oxidases. Multiple abnormalities in the control of polyamine metabolism and uptake might be responsible for increased levels of polyamines in cancer cells as compared to that of normal cells. This review is designed to look at the current research in polyamine biosynthesis, catabolism, and transport pathways, enumerate the functions of polyamines, and assess the potential for using polyamine metabolism or function as targets for cancer therapy.
Expression of activation‐induced cytidine deaminase decreases throughout the life
Authors: Radu D. L. , Kodera T. , Bona C.
Published: May 2007

Activation‐induced cytidine deaminase (AID) is an RNA editing enzyme, which contributes to generation of new functional genes from a restricted number of genes of plant and animal genome. This enzyme was involved in the process of somatic mutation and class switching in vertebrate. Since the rate of somatic mutations is variable throughout ontogeny, we have studied the transcription of AID in 3 to 24 month‐old Balb/c mice. Our results demonstrate a significant decrease of the transcription of the AID gene with aging. The decreased AID activity is not related to variation of phenotypic and functional properties of B cells throughout the life. This observation can explain the low rate of somatic mutation in aged animals.
Cytokine gene expression in monocytes of patients undergoing cardiopulmonary bypass surgery evaluated by real‐time PCR
Authors: Zimmermann Anja K. , Simon P. , Seeburger J. , Hoffmann J. , Ziemer G. , Aebert H. , Wendel H. P.
Published: May 2007

Cardiopulmonary bypass (CPB) surgery induces systemic release of proinflammatory cytokines causing unspecific inflammatory reactions. This study deals with the development of a sensitive technique for detecting changes at the mRNA level in monocytes of patients undergoing CPB surgery, by using real‐time PCR. Blood samples from patients undergoing elective coronary artery bypass grafting were obtained at six different time points. RNA was extracted from isolated monocytes and cDNA was synthesized by reverse transcriptase. CPB surgery induced gene expression of IL‐β, IL‐6, IL‐8, and TNF‐alpha, followed by a decrease below the preoperative expression values 6 h post CPB. High significant increases in gene expression for IL‐8 at the end of surgery (p = 0.001) were detected. Real‐time PCR is a powerful tool for getting simultaneously numerous sensitive, accurate, and reliable results from small amounts of biological material. This method avoids time‐consuming and hazardous post‐PCR manipulations and decreases the potential risk of PCR contamination.
Mast cells in tissue response to dentistry materials: an adhesive resin, a calcium hydroxide and a glass ionomer cement
Authors: De Oliveira Mussel R. L. , De Sá Silva E. , Costa Andréa Monte Alto , Mandarim‐De‐Lacerda C. A.
Published: May 2007

Synthetic materials used in dentistry may trigger various inflammatory responses. In order to evaluate biocompatibility, standardized implants of Calcium Hydroxide (CH), Glass Ionomer Cement (GIC) and Light‐activated Dental Adhesive (LDA) were surgically introduced into Wistar rats’back bone. Six (experimental) animal groups, five each, and two Sham (S) groups were studied after 15 and 30 days from surgery. In each animal, the density of mast cells and interstitial fibrosis volume was evaluated by quantitative light microscopy. In addition, the interaction between the disk material and its fibrous capsule was evaluated by scanning electron microscopy. In addition, the interaction between the disk material and its fibrous capsule was evaluated by scanning electron microscopy. The density of mast cells per area (NA[mast cells]) was lower in CH group than in LDA group. GIC group displayed NA[mast cells]) results intermediate between CH and LDA groups (p<0.05). The smallest interstitial fibrosis volume density (VV(f)) was observed in CH group, the in GIC group, whilet he greatest in LDA group. After 30 days, the fibrosis in LDA group was 30% higher than in CH group (p<0.05). In S group, discreet fibrosis restricted to surgical area was present, with few mast cells near the vessels. Significant interaction between fibrous capsule and the surrounding disk material was most evident in CH group. The implanted materials induced mast cell migration, distinc fibrosis development, suggesting that CH is the most biocompatible material among those tested.
Genetic‐dependency of peroxisomal cell functions ‐ emerging aspects
Authors: Latruffe N. , Vamecq J. , Malki M. Cherkaoui
Published: May 2007

This paper reviews aspects concerning the genetic regulation of the expression of the well studied peroxisomal genes including those of fatty acid β‐oxidation enzymes; acyl‐CoA oxidase, multifunctional enzyme and thiolase from different tissues and species. An important statement is PPARα, which is now long known to be in rodents the key nuclear receptor orchestrating liver peroxisome proliferation and enhanced peroxisomal β‐oxidation, does not appear to control so strongly in man the expression of genes involved in peroxisomal fatty acid β‐oxidation related enzymes. In this respect, the present review strengthens among others the emerging concept that, in the humans, the main genes whose expression is up‐regulated by PPARα are mitochondrial and less peroxisomal genes. A special emphasis is also made on the animal cold adaptation and on need for sustained study of peroxisomal enzymes and genes; challenging that some essential roles of peroxisomes in cell function and regulation still remain to be discovered.