Role of the C-C chemokine receptor-2 in a murine model of injury-induced osteoarthritis.

OBJECTIVE: We previously found in our embryonic studies that proper regulation of the chemokine CCL12 through its sole receptor CCR2, is critical for joint and growth plate development. In the present study, we examined the role of CCR2 in injury-induced-osteoarthritis (OA). METHOD: We used a murine model of injury-induced-OA (destabilization of medial meniscus, DMM), and systemically blocked CCR2 using a specific antagonist (RS504393) at different times during disease progression. We examined joint degeneration by assessing cartilage (cartilage loss, chondrocyte hypertrophy, MMP-13 expression) and bone lesions (bone sclerosis, osteophytes formation) with or without the CCR2 antagonist. We also performed pain behavioral studies by assessing the weight distribution between the normal and arthritic hind paws using the IITS incapacitance meter. RESULTS: Testing early vs delayed administration of the CCR2 antagonist demonstrated differential effects on joint damage. We found that OA changes in articular cartilage and bone were ameliorated by pharmacological CCR2 blockade, if given early in OA development: specifically, pharmacological targeting of CCR2 during the first 4 weeks (wks) following injury, reduced OA cartilage and bone damage, with less effectiveness with later treatments. Importantly, our pain-related behavioral studies showed that blockade of CCR2 signaling during early, 1-4 wks post-surgery or moderate, 4-8 wks post-surgery, OA was sufficient to decrease pain measures, with sustained improvement at later stages, after treatment was stopped. CONCLUSIONS: Our data highlight the potential efficacy of antagonizing CCR2 at early stages to slow the progression of post-injury OA and, in addition, improve pain symptoms.

Poor glycaemic control in type 2 diabetes patients reduces endothelial progenitor cell number by influencing SIRT1 signalling via platelet-activating factor receptor activation.

AIMS/HYPOTHESIS: Downregulation of levels of endothelial progenitor cells (EPCs) during in-vitro short-term exposure to high glucose concentrations relates to reduced activity of silent information regulator 1 (SIRT1) and increased synthesis of platelet-activating factor (PAF). We investigated the possible relationship between PAF and SIRT1 pathways in EPCs during altered glucose homeostasis. METHODS: SIRT1 and PAF receptor (PAF-R) levels were determined by western blot, RT-PCR and confocal laser-scanning microscopy. In-vivo experiments were performed on 48 type 2 diabetic patients (25 with poor glycaemic control and 23 with good glycaemic control) and 20 control individuals. In-vitro experiments with the PAF-R antagonist CV3988 were performed on EPCs isolated from leucocyte-rich buffy coat of healthy human donors. RESULTS: Decreased SIRT1 protein levels were observed in EPCs from type 2 diabetic patients compared with control individuals (p < 0.01). Notably, the SIRT1 level was consistently lower in patients with poor glycaemic control than in those with good glycaemic control (p < 0.01). Diabetic patients also showed an upregulation of PAF-Rs; this response occurred to a greater extent in individuals with poor glycaemic control than in those with good glycaemic control. In-vitro experiments confirmed that EPCs respond to PAF stimulation with decreased SIRT1 protein and SIRT1 mRNA levels. Moreover, reduction of SIRT1 levels and activity were abolished by CV3988. CONCLUSIONS/INTERPRETATION: These findings unveil a link between PAF and SIRT1 pathways in EPCs that contributes to the deleterious effect of hyperglycaemia on the functional properties of EPCs, crucial in diabetes and peripheral vascular complications.

Increased salience of gains versus decreased associative learning differentiate bipolar disorder from schizophrenia during incentive decision making.

BACKGROUND: Abnormalities in incentive decision making, typically assessed using the Iowa Gambling Task (IGT), have been reported in both schizophrenia (SZ) and bipolar disorder (BD). We applied the Expectancy-Valence (E-V) model to determine whether motivational, cognitive and response selection component processes of IGT performance are differentially affected in SZ and BD. METHOD: Performance on the IGT was assessed in 280 individuals comprising 70 remitted patients with SZ, 70 remitted patients with BD and 140 age-, sex- and IQ-matched healthy individuals. Based on the E-V model, we extracted three parameters, 'attention to gains or loses', 'expectancy learning' and 'response consistency', that respectively reflect motivational, cognitive and response selection influences on IGT performance. RESULTS: Both patient groups underperformed in the IGT compared to healthy individuals. However, the source of these deficits was diagnosis specific. Associative learning underlying the representation of expectancies was disrupted in SZ whereas BD was associated with increased incentive salience of gains. These findings were not attributable to non-specific effects of sex, IQ, psychopathology or medication. CONCLUSIONS: Our results point to dissociable processes underlying abnormal incentive decision making in BD and SZ that could potentially be mapped to different neural circuits.

White-matter abnormalities in the right posterior hemisphere in generalized anxiety disorder: a diffusion imaging study.

BACKGROUND: Prior imaging studies have shown structural, functional and biochemical impairments in patients with generalized anxiety disorder (GAD), particularly in the right hemisphere. In this study we investigated, for the first time to the best of our knowledge, the white-matter microstructure organization in GAD. METHOD: A total of 12 patients with DSM-IV GAD and 15 matched healthy controls underwent a magnetic resonance imaging session of diffusion weighted imaging, exploring white-matter water molecules by the means of apparent diffusion coefficients (ADCs). Regions of interests were placed in the frontal, parietal, temporal and occipital lobes and in the splenium and genu of the corpus callosum, bilaterally. RESULTS: ADC measures were significantly greater in patients with GAD in the right splenium and right parietal cortex compared with healthy controls (p⩽0.002). No significant correlations between ADCs and age or clinical variables were found. CONCLUSIONS: We provide evidence that GAD is associated with disrupted white-matter coherence of posterior right hemisphere regions, which may partly sustain the impaired cognitive regulation of anxiety. Future diffusion imaging investigations are expected to better elucidate the communication between the parietal cortex and other right hemisphere regions in sustaining the cognitive processing of social and emotional stimuli in patients with GAD.

Structural and functional insights into Aeropyrum pernix OppA, a member of a novel archaeal OppA subfamily.

In this study we gain insight into the structural and functional characterization of the Aeropyrum pernix oligopeptide-binding protein (OppA(Ap)) previously identified from the extracellular medium of an Aeropyrum pernix cell culture at late stationary phase. OppA(Ap) showed an N-terminal Q32 in a pyroglutamate form and C-terminal processing at the level of a threonine-rich region probably involved in protein membrane anchoring. Moreover, the OppA(Ap) protein released into the medium was identified as a "nicked" form composed of two tightly associated fragments detachable only under strong denaturing conditions. The cleavage site E569-G570 seems be located on an exposed surface loop that is highly conserved in several three-dimensional (3D) structures of dipeptide/oligopeptide-binding proteins from different sources. Structural and biochemical properties of the nicked protein were virtually indistinguishable from those of the intact form. Indeed, studies of the entire bacterially expressed OppA(Ap) protein owning the same N and C termini of the nicked form supported these findings. Moreover, in the middle exponential growth phase, OppA(Ap) was found as an intact cell membrane-associated protein. Interestingly, the native exoprotein OppA(Ap) was copurified with a hexapeptide (EKFKIV) showing both lysines methylated and possibly originating from an A. pernix endogenous stress-induced lipoprotein. Therefore, the involvement of OppA(Ap) in the recycling of endogenous proteins was suggested to be a potential physiological function. Finally, a new OppA from Sulfolobus solfataricus, SSO1288, was purified and preliminarily characterized, allowing the identification of a common structural/genetic organization shared by all "true" archaeal OppA proteins of the dipeptide/oligopeptide class.

Altered microstructure integrity of the amygdala in schizophrenia: a bimodal MRI and DWI study.

BACKGROUND: The amygdala plays a central role in the fronto-limbic network involved in the processing of emotions. Structural and functional abnormalities of the amygdala have recently been found in schizophrenia, although there are still contradictory results about its reduced or preserved volumes. METHOD: In order to address these contradictory findings and to further elucidate the possibly underlying pathophysiological process of the amygdala, we employed structural magnetic resonance imaging (MRI) and diffusion weighted imaging (DWI), exploring amygdalar volume and microstructural changes in 69 patients with schizophrenia and 72 matched healthy subjects, relating these indices to psychopathological measures. RESULTS: Measuring water diffusivity, the apparent diffusion coefficients (ADCs) for the right amygdala were found to be significantly greater in patients with schizophrenia compared with healthy controls, with a trend for abnormally reduced volumes. Also, significant correlations between mood symptoms and amygdalar volumes were found in schizophrenia. CONCLUSIONS: We therefore provide evidence that schizophrenia is associated with disrupted tissue organization of the right amygdala, despite partially preserved size, which may ultimately lead to abnormal emotional processing in schizophrenia. This result confirms the major role of the amygdala in the pathophysiology of schizophrenia and is discussed with respect to amygdalar structural and functional abnormalities found in patients suffering from this illness.

A highly selective oligopeptide binding protein from the archaeon Sulfolobus solfataricus.

SSO1273 of Sulfolobus solfataricus was identified as a cell surface-bound protein by a proteomics approach. Sequence inspection of the genome revealed that the open reading frame of sso1273 is associated in an operon-like structure with genes encoding all the remaining components of a canonical protein-dependent ATP-binding cassette (ABC) transporter. sso1273 gene expression and SSO1273 protein accumulation on the cell surface were demonstrated to be strongly induced by the addition of a peptide mixture (tryptone) to the culture medium. The native protein was obtained in multimeric form, mostly hexameric, under the purification conditions used, and it was characterized as an oligopeptide binding protein, named S. solfataricus OppA (OppA(Ss)). OppaA(Ss) possesses typical sequence patterns required for glycosylphosphatidylinositol lipid anchoring, resulting in an N-linked glycoprotein with carbohydrate moieties likely composed of high mannose and/or hybrid complex carbohydrates. OppA(Ss) specifically binds oligopeptides and shows a marked selectivity for the amino acid composition of substrates when assayed in complex peptide mixtures. Moreover, a truncated version of OppA(Ss), produced in recombinant form and including the putative binding domain, showed a low but significant oligopeptide binding activity.

Changing patterns in HIV-1 non-B clade prevalence and diversity in Italy over three decades.

BACKGROUND: HIV-1 non-B subtypes have recently entered Western Europe following immigration from other regions. The distribution of non-B clades and their association with demographic factors, over the entire course of the HIV-1 epidemic, have not been fully investigated in Italy. METHODS: We carried out a phylogenetic analysis of HIV-1 pol sequences derived from 3670 patients followed at 50 Italian clinical centres over nearly three decades. RESULTS: Overall, 417 patients (11.4%) carried non-B subtypes. The prevalence of non-B strains increased from 2.6% in 1980-1992 to 18.9% in 1993-2008 (P<0.0001) in a subset of 2479 subjects with a known year of diagnosis. A multivariate analysis on a subset of 1364 patients for whom relevant demographic data were available indicated that African ethnicity, heterosexual route of infection and year of diagnosis were independently associated with non-B HIV-1 infection (P ≤ 0.0001). All pure subtypes, except for clade K, and seven circulating recombinant forms were detected, accounting for 56.6 and 34.1% of the non-B infections, respectively. The F1 subtype was the most prevalent non-B clade among Europeans and was acquired heterosexually in half of this patient population. Unique recombinant forms accounted for 9.4% of the non-B sequences and showed a B/F1 recombination pattern in one-third of cases. CONCLUSIONS: The circulation of non-B clades has significantly increased in Italy in association with demographic changes. Spread of the F1 subtype and B/F recombinants appears to predominate, which may result in a redistribution of the relative proportions of the different strains, and this could lead to overlapping epidemics. Thus, the HIV-1 landscape in Italy may in future be distinct from that of the rest of Europe.

Ion, protein, phospholipid and energy substrate content of oviduct fluid during the oestrous cycle of buffalo (Bubalus bubalis).

The aim of this research was to analyse the composition of oviduct fluid (ODF) in buffalo cows at different oestrous cycle phases to fulfil the requirements of buffalo embryos in vitro. ODF was collected by chronic cannulation from three cows that were synchronized by administering a synthetic prostaglandin. Based on hormonal profiles, the pre-ovulatory, ovulatory, post-ovulatory and luteal phases of the oestrous cycle were defined. The volume of ODF produced (ml/24 h) was influenced by the oestrous cycle, with values (mean ± SE) around ovulation (1.0 ± 0.2) greater (p < 0.05) than in both the luteal (0.4 ± 0.1) and the post-ovulatory phases (0.5 ± 0.1), but not different from the intermediate values in the pre-ovulatory phase (0.8 ± 0.2). Among cycle phases, no differences were found in sodium, potassium, calcium and magnesium concentrations (130.0 ± 1.1, 5.1 ± 0.3, 2.8 ± 0.1 and 0.59 ± 0.04 mmol/l respectively). Interestingly, the chloride secretion (µm/24 h) was higher (p < 0.05) at ovulation (150.2 ± 16.5) than during both the luteal (73.7 ± 22.0) and the post-ovulatory phases (63.7 ± 11.2), with intermediate values in the pre-ovulatory phase (113.4 ± 23.5). Glucose concentration (mmol/l) was higher (p = 0.056) in the pre-ovulatory phase (0.06 ± 0.02) than in the luteal (0.02 ± 0.01) and post-ovulatory (0.02 ± 0.01) phases but not different from values in the ovulatory phase (0.04 ± 0.02). Concentrations of pyruvate and lactate among oestrous cycle phases were similar (0.08 ± 0.01 and 1.0 ± 0.1 mmol/l respectively). The total quantity of phospholipids (µmol/24 h) was greater (p < 0.05) at ovulation (0.21 ± 0.02) compared with the luteal, pre-ovulatory and post-ovulatory phases of the cycle (0.09 ± 0.02, 0.13 ± 0.02 and 0.09 ± 0.01 respectively). No differences were found in either the protein concentration (1.8 ± 0.3 mg/ml) or the quantity of proteins secreted in 24 h (1.8 ± 0.4 mg) among oestrous cycle phases. In conclusion, this study provides the first characterization of buffalo ODF during the oestrous cycle, showing species-specific differences that may be useful for developing suitable media for buffalo in vitro embryo production.

Burnout in teachers: an Italian survey.

Over the past 50 years, education has become more complex. The demand for quality and accountability in education had also increased. These demands have increased pressure on teachers, with the result that teaching is now regarded by teachers as highly stressful. The purpose of the study was to examine burnout among teachers in a region of Italy including the risk factors of burnout and the strategies used by teachers to prevent and deal with stress. The research was carried out on a sample of 508 teachers. The questionnaire incorporated the Maslach Burnout Inventory modified for Italian teachers--a 22 item questionnaire designed to assess the three aspects of burnout syndrome: emotional exhaustion, depersonalization and lack of personal achievement. The results highlight the presence of substantial levels of emotional exhaustion in a significant number of teachers. The rate of burnout among teachers is 19.7%. The data are lower than for a sample of Italy as a whole and than for European countries where rates of burnout range between 25% and 35%.

Increased fronto-temporal perfusion in bipolar disorder.

OBJECTIVES: Previous imaging reports showed over-activation of fronto-limbic structures in bipolar patients, particularly in response to emotional stimuli. In this study, for the first time, we used perfusion weighted imaging (PWI) to analyze lobar cerebral blood volume (CBV) in bipolar disorder to further explore the vascular component to its pathophysiology. METHODS: Fourteen patients with DSM-IV bipolar disorder (mean age+/-SD=49.00+/-12.30 years; 6 males, 8 females) and 29 normal controls (mean age+/-SD=45.07+/-10.30 years; 13 males, 16 females) were studied. PWI images were obtained following intravenous injection of paramagnetic contrast agent (Gadolinium-DTPA), with a 1.5 T Siemens magnet using an echo-planar sequence. The contrast of enhancement (CE), was calculated pixel by pixel as the ratio of the maximum signal intensity drop during the passage of contrast agent (Sm) by the baseline pre-bolus signal intensity (So) (CE=Sm/So*100) for frontal, temporal, parietal, and occipital lobes, bilaterally, on two axial images. Higher CE values correspond to lower CBV and viceversa. RESULTS: Bipolar patients had significantly lower CE values in left frontal and temporal lobes (p=0.01 and p=0.03, respectively) and significantly inverse laterality index for frontal lobe (p=0.017) compared to normal controls. No significant correlations between CE measure and age or clinical variables were found (p>0.05). CONCLUSION: This study found increased left frontal and temporal CBV in bipolar disorder. Fronto-temporal hyper-perfusion may sustain over-activation of these structures during emotion modulation, which have been observed in patients with bipolar illness.

Anterior cingulate volumes in schizophrenia: a systematic review and a meta-analysis of MRI studies.

OBJECTIVES: Several MRI studies have investigated the anterior cingulate in schizophrenia, as this is a key region for emotional processing and higher executive performances. A systematic review of structural MRI studies and a meta-analysis were conducted to explore whether anterior cingulate volumes are abnormal in patients with schizophrenia. METHOD: A systematic search strategy was used to identify eligible MRI studies. Thereafter, a meta-analysis was carried out by using a random effect model. Also, a meta-regression analysis was used to assess the influence of age, gender and slice thickness on effect sizes. RESULTS: The meta-analysis was performed on seven studies. These results showed that the anterior cingulate volumes were significantly reduced in patients compared to healthy controls. Significant heterogeneity between these studies was observed. The meta-regression demonstrated that the effect size was significantly related only to slice thickness. CONCLUSIONS: Our work confirmed the presence of abnormally reduced anterior cingulate volumes in schizophrenia. However, several methodological issues limited the interpretation of these findings. Among these were different MR acquisition parameters and the small size of the sample, which was mostly composed of chronic patients. Future MRI studies should be planned to better understand the functional expression of anterior cingulate structural abnormalities.

Effect of gestational hypercholesterolaemia on omental vasoreactivity, placental enzyme activity and transplacental passage of normal and oxidised fatty acids.

OBJECTIVE: Maternal hypercholesterolaemia during pregnancy increases lipid peroxidation in mothers and fetuses and programs increased susceptibility to atherosclerosis later in life. The objective of this study was to elucidate the role of the placenta in mediating oxidative stress from mother to offspring. DESIGN: Comparison between normo- and hypercholesterolaemic mothers (n = 36 each) and their children. SETTING: Obstetric wards, hospitals of the University of Naples and Regione Campania. POPULATION: Healthy primiparas delivering by caesarean section. METHODS: Biochemical measurements of oxidative stress and serum leptin in cord plasma and placenta, immunochemistry of placenta microvessels, and vasoreactivity studies were performed. MAIN OUTCOME MEASURES: Oxidative status (i.e. lipid composition and content of oxidised fatty acids, activity of pro- and antioxidant enzymes, immunohistochemical presence of oxidation-specific epitopes) in maternal and cord blood and in placental tissue, as well as vascular reactivity in omental arteries. RESULTS: Hypercholesterolaemia during pregnancy was associated with extensive changes in fatty acid composition of both maternal and cord blood lipids, sufficient to alter vasoreactivity of omental vessels. Results also indicated that the placenta is not only subject to substantial oxidative stress, but that it may further increase fetal oxidative stress through changes of pro- and antioxidant enzyme activities. CONCLUSIONS: The placenta plays an important role in both transmitting and enhancing pathogenic effects of gestational hypercholesterolaemia.

Human herpesvirus-6B active infection associated with relapsing bilateral anterior optic neuritis.

BACKGROUND AND OBJECTIVES: Human herpesvirus-6 (HHV-6) is the causative agent of exanthem subitum. Both HHV-6 variants, A and B, have been associated with central nervous system (CNS) diseases, suggesting a wide neuropathogenic potential. We describe a case of recurrent bilateral anterior optic neuritis with HHV-6 active infection associated with clinical relapses. CASE REPORT: A 23-year old woman presented with progressive visual impairment, bilateral papillitis and painful ocular movements. Nested polymerase chain reaction (PCR) for DNA viruses, HHV-6 variant specific real time quantitative PCR, serological analysis and retrotranscription PCR (RT-PCR) for HHV-6 mRNA transcripts were performed. Nested PCR in PBMC and CSF samples was negative for all viruses but positive for HHV-6 DNA, subtyped as HHV-6B. The disease had a relapsing/remitting course. During relapses PBMC samples remained positive for HHV-6 DNA, and HHV-6 active infection was confirmed by the presence of anti-HHV-6 IgM and of HHV-6 U27 mRNA transcript. High viremia levels and relapses were overlapping. After the last relapse, the patient was successfully treated with gancyclovir. CONCLUSIONS: The case reported here suggests a possible association of HHV-6 in bilateral optic neuritis. HHV-6 could be monitored when bilateral optic neuritis is identified, in order to establish an appropriate antiviral therapy.

Health-related quality of life in older people using benzodiazepines: a cross-sectional study.

Aim of this study is to investigate the QoL older people making regular use of BDZ. All subjects aged 65-84 years attending their General Practitioners were invited to fill in a questionnaire about their consumption of BDZ and all the subjects consuming BDZ to fill in the Medical Outcome Measures Short Form-36 (MOS SF-36) and the Primary Care Evaluation of Mental Disorders (PRIME-MD) questionnaires. A total of 2,246 subjects used BDZ and 1,109 (49.4%) of them filled in the MOS SF-36 questionnaire. 1,005 of these participants also completed the PRIME-MD questionnaire (90.6%). The presence of sleep disorders and the characteristics of the BDZ used were not associated with any score in the MOS SF-36 questionnaire, whereas the Prime diagnosis was the most important predictor, since subjects with depression and/or anxiety had a lower mean score on each scale than subjects without disorders. Among a sample of Italian seniors taking BDZ, QoL was associated with the presence of anxiety and/or depression. Age, gender, education and the presence of cardiovascular diseases or stroke were associated with specific aspects of QoL, when anxiety and depression were controlled for.

Unaltered Oxytocin and Vasopressin Plasma Levels in Patients with Schizophrenia After 4 Months of Daily Treatment with Intranasal Oxytocin.

The neuropeptide oxytocin (OXT) has been proposed as a treatment for a number of neuropsychiatric disorders characterised by impaired social behaviour, including schizophrenia. Although several studies have reported the chronic administration of OXT to be safe and tolerable, its effects on circulating levels of OXT, as well as the related neuropeptide arginine vasopressin (AVP), have not been assessed. In the present study, in a within-subjects cross-over, double-blind, randomised controlled trial, we assayed the plasma levels of OXT and AVP in 31 patients with schizophrenia who were treated daily for 4 months with 40 IU of intranasal OXT or placebo. Our data indicate a mean ± SD baseline OXT concentration of 1.62 ± 0.68 pg/ml, as determined by radioimmunoassay, which did not display any significant variation after chronic treatment with OXT or placebo. Similarly, the mean ± SD baseline AVP value of 2.40 ± 1.26 pg/ml remained unchanged. The present study also assessed cardiovascular and body fluid indicators (osmolality, plasma sodium concentration and systolic blood pressure), as well as a parameter for food intake (body mass index), with all observed to remain stable. By reporting that daily treatment with 40 IU of intranasal OXT or placebo for 4 months does not impact on OXT and AVP plasma levels, nor on cardiovascular, body fluids and food intake parameters, the present study represents an important step towards developing OXT as a safe treatment.

Transferrin-Targeted Nanoparticles Containing Zoledronic Acid as a Potential Tool to Inhibit Glioblastoma Growth.

The treatment of glioblastoma (GBM) is a challenge for the biomedical research since cures remain elusive. Its current therapy, consisted on surgery, radiotherapy, and concomitant chemotherapy with temozolomide (TMZ), is often uneffective. Here, we proposed the use of zoledronic acid (ZOL) as a potential agent for the treatment of GBM. Our group previously developed self-assembling nanoparticles, also named PLCaPZ NPs, to use ZOL in the treatment of prostate cancer. Here, we updated the previously developed nanoparticles (NPs) by designing transferrin (Tf)-targeted self-assembling NPs, also named Tf-PLCaPZ NPs, to use ZOL in the treatment of brain tumors, e.g., GBM. The efficacy of Tf-PLCaPZ NPs was evaluated in different GBM cell lines and in an animal model of GBM, in comparison with PLCaPZ NPs and free ZOL. Tf-PLCaPZ NPs were characterized by a narrow size distribution and a high incorporation efficiency of ZOL. Moreover, the presence of Tf significantly reduced the hemolytic activity of the formulation. In vitro, in LN229 cells, a significant uptake and cell growth inhibition after treatment with Tf-PLCaPZ NPs was achieved. Moreover, the sequential therapy of TMZ and Tf-PLCaPZ NPs lead to a superior therapeutic activity compared to their single administration. The results obtained in mice xenografted with U373MG, revealed a significant anticancer activity of Tf-PLCaPZ NPs, while the tumors remained unaffected with free TMZ. These promising results introduce a novel type of easy-to-obtain NPs for the delivery of ZOL in the treatment of GBM tumors.

Free radical involvement in doxorubicin-induced electrophysiological alterations in rat papillary muscle fibres.

OBJECTIVE: This work was designed to determine whether the doxorubicin-induced changes in heart electrical activity are due to increased free radical production and membrane oxidative damage. METHODS: Four groups of rats (60 days old) were used. One group was untreated and the others were treated with doxorubicin (DXR), DXR and vitamin E, and DXR and N-acetylcysteine (NAC), respectively. DXR was administered by single i.p. injection (20 mg/kg b.wt.). Vitamin E was administered by ten daily i.m. injections (100 mg/kg), while NAC (100 mg/kg) was injected i.p. 1 h before and 7 h after DXR. The effectiveness of the drug in inducing oxidative stress in different tissues and of the antioxidants in offering protection was established by determining antioxidant capacity, susceptibility to oxidative stress, and lipid peroxidation in heart, liver, and blood. The drug effect on heart electrical activity was determined by measuring the heart rate in vivo and action potential configuration in papillary muscle fibres in vitro. Heart lipid peroxidation and electrical activity were also examined in both vitamin E and NAC-treated rats. RESULTS: DXR treatment decreased antioxidant capacity and increased lipid peroxidation and susceptibility to oxidative stress in heart and blood, but not in liver. DXR administration to rats treated with antioxidants did not produce significant changes in antioxidant capacity and susceptibility to oxidative stress even in heart and blood. Furthermore, lipid peroxidation in heart and liver from DXR- and vitamin E-treated rats, and in liver from DXR- and NAC-treated rats was lower than in untreated controls. DXR treatment also increased the duration of ventricular action potentials in untreated rats, but not in antioxidant-treated rats. The treatment of control animals with the antioxidants affected lipid peroxidation, but not cardiac electrical activity. CONCLUSIONS: The protection offered by antioxidants against electrophysiological alterations indicates a free radical involvement in such alterations. In contrast, although electrical modifications are associated with increased peroxidative processes and both are prevented by the antioxidants, it is not yet clear whether a causative relationship exists between them.

Evaluation of Agreement between HRT III and iVue OCT in Glaucoma and Ocular Hypertension Patients.

Purpose. To determine the agreement between Moorfields Regression Analysis (MRA), Glaucoma Probability Score (GPS) of Heidelberg retinal tomograph (HRT III), and peripapillary nerve fibers thickness by iVue Optical Coherence Tomography (OCT). Methods. 72 eyes with ocular hypertension or primary open angle glaucoma (POAG) were included in the study: 54 eyes had normal visual fields (VF) and 18 had VF damage. All subjects performed achromatic 30° VF by Octopus Program G1X dynamic strategy and were imaged with HRT III and iVue OCT. Sectorial and global MRA, GPS, and OCT parameters were used for the analysis. Kappa statistic was used to assess the agreement between methods. Results. A significant agreement between iVue OCT and GPS for the inferotemporal quadrant (κ: 0.555) was found in patients with abnormal VF. A good overall agreement between GPS and MRA was found in all the eyes tested (κ: 0.511). A good agreement between iVue OCT and MRA was shown in the superonasal (κ: 0.656) and nasal (κ: 0.627) quadrants followed by the superotemporal (κ: 0.602) and inferotemporal (κ: 0.586) sectors in all the studied eyes. Conclusion. The highest percentages of agreement were found per quadrant of the MRA and the iVue OCT confirming that in glaucoma damage starts from the temporal hemiretina.

Regulation of the biosynthesis of acyl analogs of platelet-activating factor by purinergic agonist in endothlial cells.

We have previously shown that platelet-activating factor (PAF)-dependent transacetylase (TA) contains three catalytic activities, namely PAF: lysophospholipid TA (TAL), PAF: sphingosine TA (TAs) and PAF acetylhydrolase. It serves as a modifier of PAF actions by producing different lipid signal molecules. The TAL activity is involved in the biosynthesis of acyl analogs of PAF (acyl-PAF, 1-acyl-2-acetyl-sn-glycero-3-phosphocholine, acylacetyl-GPC) in agonist-stimulated endothelial cells. In the present investigation, we have studied the mechanism(s) by which the TA activity is regulated in ATP-treated endothelial cells. We have demonstrated that ATP, and thiol-modifying agents with ATP, specifically regulate only the TAL part of the TA activities.