Molecular and cellular outcomes of quercetin actions on healthy and tumor osteoblasts

There is a global trend in the use of natural bioactive compounds to complement conventional therapies in bone diseases. In this work, we studied the effects of the phytoestrogen quercetin (QUE) in healthy and tumor osteoblasts. We found that QUE (1 μM, 48 h) significantly increased the cell number and the viability of healthy human osteoblasts (hFOB cells) determined by a trypan blue and a MTS assay, respectively, among other concentrations tested. In addition, wound healing and cellular adhesion assays also demonstrated that 1 μM of QUE significantly stimulated both parameters in osteoblasts. Moreover, osteoblast differentiation was also triggered by QUE in an osteogenic medium by measuring alkaline phosphatase activity, calcium deposition, and collagen levels. Herein, a concentration of 0.01 μM of QUE showed an increment in these differentiation markers and an activation of AKT/GSK3β/β-catenin pathway, determined by a Western blot analysis. In addition, immunocytochemistry and subcellular fraction studies indicated an increase of β-catenin localization in the plasma membrane after QUE treatment. Otherwise, QUE (20-100 μM) decreased the cell number and the viability in tumor osteoblasts (ROS 17/2.8 cells) after 48 h. Furthermore, QUE (100 μM) decreased AKT(Ser473) and the pro-apoptotic protein BAD(Ser136) phosphorylation. In addition, the ERK1/2 phosphorylation increased leading to osteosarcoma cell death since pre-treatment with the MEK inhibitor PD98059 had reverted QUE effect. Altogether, these results indicate that to stimulate the osteoblastogenesis low concentrations of QUE are required; however, these concentrations are not effective in inhibiting the growth of tumor osteoblasts, for which higher concentrations are required.

SAT0296 SERUM LEPTIN LEVELS IN SYSTEMIC SCLEROSIS PATIENTS WITH ELECTROCARDIOGRAPHIC ABNORMALITIES

Background:

Electrocardiographic (ECG) abnormalities are described in 25-75% Systemic Sclerosis (SSc) cases and they are associated with other systemic manifestations as well as with a worse prognosis. There is an increasing need for clinical and laboratory biomarkers to ameliorate the diagnostic and therapeutic approaches to patients with ECG abnormalities, due to their actual low sensitivity and specificity. Adipokines are circulating proteins that appear dysregulated in SSc and leptin in particular is synthesized in response to inflammatory conditions and seems to play a proinflammatory and pro-fibrotic action in SSc. Interesting, many studies in the last years have underlined its role in the cardiac remodeling mechanisms and in the development of cardiac fibrosis in other chronic diseases.

Objectives:

Aim of our study is to evaluate the role of leptin in the development of cardiac rhythm disorders (CRD) during SSc. Furthermore, by the analysis of the clinical and demographical parameters of our SSc patients, we tried to define other possible features associated with increased serum leptin concentration.

Methods:

We included eighty-five SSc patients, fulfilling the 2013 ACR/EULAR classification criteria, attending the Regional Rare Disease Center of Policlinico Umberto I of Rome. Fifty presented significant CRD at non-invasive diagnostic techniques (12 Lead ECG, 24-hour Holter ECG). Demographic, clinical, conventional cardiovascular risk factors were examined; instrumental and laboratory assessments were obtained, together with ECG recordings. Thirty-five SSc patients without pathologic finding at ECG traces, matched for demographic and clinical features, were recruited as the control group. In all cases, after obtaining written informed consent, blood samples were taken to measure serum levels of leptin using an ELISA assay (Life Technologies-Italia).

Results:

The fifty SSc patients with CRD (mean age 51±15 years; F:M 41:9) had pulmonary fibrosis (PF) in 32 cases (64%) and a BMI >25Kg/m2in 22 (44%) while in the control group of thirty-five SSc patients (mean age 49±16 years; F:M 33:2) PF was found in 15 (43%) and a BMI >25Kg/m2in 9 (35%); We detected significantly higher median values of serum leptin in SSc patients with CRD compared to the control group (12027 pg/ml IQR 12314 versus 6392 pg/ml IQR 7103;p 0,0009). Additionally, SSc patients with a BMI> 25 kg/m2(31 cases) as well as those with PF (47 cases) showed a significantly higher median serum leptin levels compared to those with BMI <25 kg/m2(13161 pg/ml IQR 13610 versus 8187 pg/ml IQR 8255;p 0,0008) and those without PF (11740 pg/ml IQR 11940 versus 7616 pg/ml IQR 7855;p 0,0079).

Conclusion:

To our knowledge this is the first report on high serum levels of leptin in SSc patients with CRD that also confirms its increase in those cases with a BMI >25 kg/m2and with PF, according to scientific literature data. The role of leptin in the pathogenesis of SSc remains unclear although it is already known its involvement in the development of cardiac fibrosis during other chronic diseases. On the basis of these results we speculate on leptin involvement in the pathogenesis of CRD during SSc, although further studies are needed with larger cohort of patients.

References:

[1]Vacca A et al. Rheumatology, 2014

[2]Tyndall AJ et al. Ann Rheum Dis, 2010

[3]Muresan L et al. Iran J Pub Health, 2017

[4]Sanna T et al. Indian Pacing Electrophysiol J, 2009

[5]Riccieri V et al. Clin Exp Rheumatol, 2011

[6]Żółkiewicz J et al. Arch Dermatol Res, 2019

[7]Huby AC et al. Circulation, 2015

[8]Shulze PC et al. Clin Chim Acta, 2005

[9]Van de Hoogen F et al. Arthritis Rheum, 2013

[10]Gui X et al. Biochem Biophys Res Commun, 2018

Disclosure of Interests:

Greta Pellegrino: None declared, Katia Stefanantoni Consultant of: Italfarmaco

Boehringer Ingelheim, Fausta Facioni: None declared, Carlotta Angelelli: None declared, Antonietta Gigante: None declared, Roberto Badagliacca: None declared, Carmine Dario Vizza: None declared, Sergio Morelli: None declared, Edoardo Rosato: None declared, Valeria Riccieri: None declared

Real-world efficacy and safety of lenvatinib: data from a compassionate use in the treatment of radioactive iodine-refractory differentiated thyroid cancer patients in Italy

BACKGROUND

Lenvatinib is a multi-kinase inhibitor approved for patients with radioactive iodine (RAI)-resistant differentiated thyroid cancer (DTC). Before the drug approval from the Italian National Regulatory Agency, a compassionate use programme has been run in Italy. This retrospective study aimed to analyse data from the first series of patients treated with lenvatinib in Italy.

METHODS

The primary aim was to assess the response rate (RR) and progression-free survival (PFS). Secondary end-points include overall survival (OS) and toxicity data.

RESULTS

From November 2014 to September 2016, 94 patients were treated in 16 Italian sites. Seventeen percent of patients had one or more comorbidities, hypertension being the most common (60%). Ninety-eight percent of patients were treated by surgery, followed by RAI in 98% of cases. Sixty-four percent of patients received a previous systemic treatment. Lenvatinib was started at 24 mg in 64 subjects. Partial response and stable disease were observed in 36% and in 41% of subjects, respectively; progression was recorded in 14% of patients. Drug-related side-effects were common; the most common were fatigue (13.6%) and hypertension (11.6%). Overall, median PFS and OS were 10.8 months (95% confidence interval [CI], 7.7-12.6) and 23.8 months (95% CI, 19.7-25.0) respectively.

CONCLUSION

Lenvatinib is active and safe in unselected, RAI-refractory, progressive DTC patients in real-life setting. RR and PFS seem to be less favourable than those observed in the SELECT trial, likely due to a negative selection that included heavily pretreated patients or with poor performance status.

Inhibition of Cellular DNA Synthesis and Lack of Antileukemic Activity by Non-Photoactivated Hematoporphyrin Derivative

It has been reported that cytocidal activity of light-activated hematoporphyrin (HPD) within the cells might be exploited in the therapy of experimental and human cancer. As part of a project from this laboratory aimed to study some major biologic features of HPD, it was found that [3H]thymidine incorporation in tumor cells was highly inhibited as a consequence of HPD treatment. HPD-mediated inhibition, obtained by a treatment either in vitro or in vivo, was long lasting and independent of light activation. Cellular DNA synthesis was inhibited by non toxic doses of HPD which were not influential either cell viability or cell oncogenicity. In preliminary studies, HPD-treated cells accumulated in the G1 phase of the cell cycle as detected by cytofluorometric analysis. This finding is in keeping with a likely inhibition exerted in late G, or at the beginning of the S phase of cell the cycle and might exclude a direct damage of the DNA synthetic machinery. Definitive loss of cell viability and cellular DNA inhibition was obtained immediately after the exposure of HPD-treated cells to He-Ne laser light. HPD-mediated cell lysis was dose dependent and in the order of magnitude of cytocidal doses in different cell systems. HPD antileukemic activity or HPD interactions with chemotherapeutic drugs was ruled out in L1210 leukemic mice.

Management of Fluid Balance in Continuous Renal Replacement Therapy: Technical Evaluation in the Pediatric Setting

Fluid overload control and fluid balance management represent very important factors in critically ill children requiring renal replacement therapy A relatively high fluid volume administration in children and neonates is often necessary to deliver adequate amounts of blood derivatives, vasopressors, antibiotics, and parenteral nutrition. Fluid balance errors during pediatric continuous renal replacement therapy (CRRT) might significantly impact therapy delivery and have been described as potentially lethal. The aim of this study was to evaluate the accuracy of delivered vs. prescribed net ultrafiltration (UF) during CRRT applied to 2 neonates and 2 small children, either as dialytic treatment alone or during extracorporeal membrane oxygenation (ECMO). In accordance with an Acute Dialysis Quality Initiative workgroup statement, net UF was defined as the “overall amount of fluid extracted from the patient in a given time”. Mean prescribed net UF was 18.5 ml/h (SD=6.7) during neonatal treatments and 70.3 ml/h (SD=22.5) during CRRT in small children. Daily net UF ranged from 200 mL to about 600 mL in the 2 neonates and from 1,200 to 1800 mL in the 2 children. The percentage error of delivered net UF ranged from −1.6% to 5.8% of the prescribed level. The mean error of the ECMO/CRRT patients was 3.024 ml/h vs. 0.45 m/h for the CRRT patients (p<0.001). The same difference was not evident when the 2 neonates were compared with the 2 small children (without considering the presence of ECMO). CRRT and net UF delivery appeared to be accurate, safe, and effective in this small cohort of high-risk pediatric patients.

Long-term efficacy and safety of fourth-line multikinase inhibitor treatment with lenvatinib in a young papillary thyroid carcinoma patient

Lenvatinib, a multikinase inhibitor, is approved for the treatment of patients with radioiodine-refractory metastatic thyroid cancer on the basis of a Phase III, prospective, double-blind, randomized, placebo-controlled trial that showed longer progression-free survival in the drug-treated arm. Here, we report the case of a young papillary thyroid cancer patient, pretreated with three other kinase inhibitors, who achieved a long-term clinical benefit from lenvatinib in the fourth-line setting.

Left-sided heart valve abnormalities and risk of ischemic cerebrovascular accidents in patients with systemic lupus erythematosus

The aim of the study was to assess the relationship between ischemic cerebrovascular accidents (ICVAs), that is, transient ischemic attack (TIA) or stroke, and left-sided heart valve abnormalities (LHVAs) in patients with systemic lupus erythematosus (SLE). In total, 71 consecutive SLE patients were studied.At baseline, history, clinical and laboratoryevaluations, as well as trans-thoracic echocardiography (TTE) were performed. From the original population, so patients were followed up for a mean time of 5.80 + 1.53 years. After a mean period of 5.39 + 1.42 years; 40 patients underwent a repeat TTE.

Previous ICVA history was present at baseline in 16 patients (22.5%). Of these, 13 (81.2%) had evidence of LHVAs on TTE. Previous ICVAs were significantly associated to diagnosis of secondary anti-phospholipid syndrome (SAPS), positivity for anti-cardiolipin antibodies (aCl), and LHVAs. Multivariate analysis confirmed the correlation between previous ICVAs and LHVAs. LHVAs were not more commonly observed in patients with SAPS compared to patients without SAPS. At the end of follow-up, irrespective of any differences in antithrombotic treatment, ICVAs had occurred in 13 patients.During follow-up, ICVAs had recurredin seven patients, while a first eventTIA occurredin one patient. Multivariate analysis confirmed the relationship between ICVAs and LHVAs, and a trend towards a positive correlation of the former with SAPS. This study demonstratesthat LHVAs represent a compelling risk factor for the development of ICVAs in SLE patients. Conversely, SAPS and aCl positivity, although associated with ICVAs, did not clearly correlate with LHVAs in our study. These results provide insight on the pathogenesis of ICVAs and may give clues on the potential efficacy of preventive/therapeutic strategies in different SLE subpopulations.

Quality assessment and cataloguing of telemedicine applications

We created a Web catalogue of approved telemedicine systems that authoritative Italian research bodies had made available for more general use. The evaluation process was divided into two stages: (1) classification of the telemedicine systems and rough preliminary evaluation; (2) assessment of the telemedicine products and services. The scoring method was applied to four well-known telemedicine systems that had been tested in health-care settings: an echocardiology teleconsulting and analysis system; a ward nursing management system; a virtual cooperative system for the management of oncology patients and a telepathology system based on remotely controlled microscopy. After technical revision during the standardization/qualification process, the applications were transferred successfully to eight new health-care facilities. The methodology achieved the main goal of providing effective tools, such as a set of quality control procedures for telemedicine and telehealth projects and a Web catalogue of telemedicine applications with a standardized level of quality, available to all interested parties.

Preparation of spiked grass for use as an environmental radioactivity reference material

Measurement of radionuclides from environmental samples includes a wide variety of matrix compositions and densities. To improve the traceability of environmental monitoring, LNE-LNHB intends to produce mixed γ-ray reference materials with a known mass activity and a composition as representative as possible of real environmental samples. This paper describes the preparation and characterization of a low density treated grass matrix spiked with mixed γ-emitters. This material was used in a proficiency test exercise whose results are presented.

Cobalt chloride induces metaphase when topically applied to larvae and pupae of the stingless bee Melipona scutellaris (Hymenoptera, Apidae, Meliponini)

In order to optimize preparations of bee metaphases, we tested cobalt chloride, which has been used as a metaphase inducer in other organisms, such as hamsters and fish. Four microliters of 65 mM cobalt chloride aqueous solution was topically applied to larval and pupal stages of the stingless bee Melipona scutellaris. The cerebral ganglion was removed after treatment and prepared for cytogenetic analysis. Identically manipulated untreated individuals were used as controls. The number of metaphases was increased 3-fold in treated individuals compared to controls. The micronucleus test showed no mutagenic effects of cobalt chloride on M. scutellaris cells. We concluded that cobalt chloride is a metaphase-inducing agent in M. scutellaris, thus being useful for cytogenetic analyses.

Human exposure to lead, cadmium and mercury through fish and seafood product consumption in Italy: a pilot evaluation

The presence of selected toxic heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg), was investigated in fish and seafood products, namely, blue mussel, carpet shell clam, European squid, veined squid, deep-water rose shrimp, red mullet, European seabass, gilthead seabream, Atlantic cod, European hake, Atlantic bluefin tuna and swordfish so as to assess their human exposure through diet. Metals were detected by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and hydride generation atomic absorption spectrometry (Hg-AAS). Measurements of Cd, Pb and Hg were performed by means of analytical methods validated in compliance with UNI CEI EN ISO/IEC 17025 [2005. General requirements for the competence of testing and calibration laboratories. Milano (Italy): UNI Ente Nazionale Italiano di Unificazione]. The exposure assessment was undertaken matching the levels of Cd, Pb and total Hg with consumption data related to fish and seafood products selected for this purpose. In order to establish human health implications, the estimated weekly intakes (EWIs) for Cd, Pb and Hg were compared with the standard tolerable weekly intakes (TWI) for Cd and provisional tolerable weekly intakes (PTWIs) for Pb and Hg stipulated by the European Food Safety Authority (EFSA) and the Food and Agriculture Organization/World Health Organization (FAO/WHO) Joint Expert Committee on Food Additives (JECFA). The found metal concentrations were largely below the maximum levels (MLs) established at the European Union level with the exception of Cd. This metal exceeded the MLs in squid, red mullet, European hake and Atlantic cod. Squid and blue mussel showed the highest Pb concentrations which accounted for 60% and 10% of the MLs, respectively. Highest Hg levels were found in predatory fish. The concentrations of Hg in swordfish, Atlantic bluefin tuna and red mullet accounted for 50%, 30% and 30% of the MLs, respectively. The EWIs for Cd, Pb and Hg related to the consumption of fish and seafood products by the median of the Italian total population accounted for 20%, 1.5% and 10% of the standard TWI for Cd as well as PTWIs for Pb and Hg, respectively. Furthermore, the EWIs estimated using consumption data concerning Italian consumers did not exceed the standard TWI and PTWIs, except for Cd at 95th percentile.

Role of connexin 43 in the mechanism of action of alendronate: dissociation of anti-apoptotic and proliferative signaling pathways

Bisphosphonates (BPs) inhibit osteocyte and osteoblast apoptosis via opening of connexin (Cx) 43 hemichannels and activating the extracellular signal regulated kinases ERKs. Previously, we hypothesized that intracellular survival signaling is initiated by interaction of BPs with Cx43. However, using whole cell binding assays with [(3)H]-alendronate, herein we demonstrated the presence of saturable, specific and high affinity binding sites in the Cx43-expressing ROS 17/2.8 osteoblastic cells, authentic osteoblasts and MLO-Y4 cells expressing Cx43 or not, as well as in HeLa cells lacking Cx43 expression and ROS 17/2.8 cells pretreated with agents that disassemble Cx channels. In addition, both BPs and the PTP inhibitor Na(3)VO(4) increased proliferation of cells expressing Cx43 or not. Furthermore, although BPs are internalized and inhibit intracellular enzymes in osteoclasts, whether the drugs penetrate non-resorptive bone cells is not known. To clarify this, we evaluated the osteoblastic uptake of AF-ALN, a fluorescently labeled analog of alendronate. AF-ALN was rapidly internalized in cells expressing Cx43 or not indicating that this process is not mediated via Cx43 hemichannels. Altogether, these findings suggest that although required for triggering intracellular survival signaling by BPs, Cx43 is dispensable for cellular BP binding, its uptake, as well as the proliferative effects of these agents.

Evolutionary cytogenetics of the Hoplias lacerdae, Miranda Ribeiro, 1908 group. A particular pathway concerning the other Erythrinidae fish

The taxonomy/systematics of the Erythrinidae fish is still imprecise, with several doubts on their relationships. Karyotypes and chromosomal characteristics of some species of the Hoplias lacerdae group (Erythrinidae), from different Brazilian hydrographic basins and pisciculture stations, were analyzed in the present study, using conventional Giemsa staining, C-banding, silver staining, Mithramycin and Distamycin/DAPI fluorochromes, and fluorescent in situ hybridization (FISH). A diploid chromosome number of 2n = 50 and karyotypes composed of meta- and submetacentric chromosomes without sex-related differences were found. Only one active NOR (Nucleolar Organizer Region) site was found, which was identified by silver staining (Ag-NOR) and FISH, located on the chromosome pair 11, although additional 45S rDNA sites were also mapped on other chromosome pairs only by FISH. The Ag-NOR of the chromosome pair 11 was found to be GC-rich, appearing positive after Mithramycin staining. Mithramycin-positive/DAPI-negative sites were also observed in the centromeric/pericentomeric regions of the chromosome pairs 4, 6, 15, and 19, which have also affinity to silver nitrate. However, these four sites were not detected by FISH with the rDNA probe, indicating to be only argentophilic GC-rich heterochromatic regions. Chromosome data show that the karyotype evolution in Hoplias lacerdae group is relatively conserved and follows a particular pathway concerning the other Erythrinidae fishes, such as Hoplias malabaricus, Hoplerythrinus unitaeniatus, and Erythrinus erythrinus, in which polytypic karyotypes are found. Thus, the H. lacerdae group shows chromosome features that are not closely related to those of the congeneric H. malabaricus group. These finds, together with genetic and morphologic data, are important tools to be considered in a major revision of the Erythrinidae family, as well as for conservation programs.

Immunogenicity of advanced glycation end products in diabetic patients and in nephropathic non-diabetic patients on hemodialysis or after renal transplantation

Advanced glycation end products (AGE) increase as a consequence of diabetic hyperglycemia and, in nephropathic patients, following renal function loss. Protein-bound AGE behave as immunogens, inducing formation of specific antibodies (Ab-AGE). In this work AGE immunogenicity was studied in 42 diabetic patients, 26 nephropathic patients on hemodialysis and 26 patients with end-stage renal disease who underwent kidney transplantation and in 20 normal subjects. Non-oxidation-derived AGE (nox-AGE), oxidation-derived AGE (ox-AGE) and Ab-AGE were measured by competitive or direct enzyme-linked immunosorbent assay (ELISA) and circulating immune complexes (CIC) by C1q ELISA. Nox- AGE increased significantly in all patient groups (p < or = 0.05 to < or = 0.0001) except in patients on hemodialysis for less than 6 yr. Ox-AGE were only significantly increased in patients transplanted more than 3 yr previously (p < 0.05). Ab-AGE were significantly lower than controls in both diabetic groups and in patients on hemodialysis for more than 6 yr (p < 0.005 to < 0.0001) and not unlike controls in the other groups. These results demonstrate that hemodialysis or renal transplantation can, initially, reduce either nox- or ox-AGE levels, which however go back to being high in time. Renal transplantation fails to normalize nox-AGE. More importantly, plasma Ab-AGE levels are reduced or unchanged in all patient groups in comparison with controls, despite higher circulating AGE levels. This suggests the importance of tissue-bound AGE as Ab-AGE targets. Additional interventions are needed to control AGE levels in treated nephropathic patients. The search and quantification of specific Ab-AGE would give more meaningful results if performed over specific tissue specimens.

Experience at Italian National Institute of Health in the assessment of the quality in telemedicine: submission to a quality control process

For applying a quality control of the telemedicine (TM) applications, in order to prevent device and/or service failure and to standardize some features of TM applications, a telemedicine quality control (TM-QC) process was proposed by authors. This TM-QC process was submitted to some TM manufacturers in order to assess their products/services and applied in two following phases, during which a set of procedures and tools were delivered to the TM suppliers. In the 1 degrees phase an Informative Questionnaire (InQu) and the Classification Form (ClFo) were delivered: the InQu gathered all the relevant information about the TM application in exam, the ClFo classified the TM product as belonging to one category (or application area) of TM. In the 2nd phase a Technical File (TF) and a Quality Assessment CheckList (QACL) were delivered: the TF was intended as a technical dossier of product; the QACL was a checklist of requirements that TM products must be agreed. The number of met requirements was computed and a Quality Level (QL), ranging from Basic Quality Level (QL1-B) to the Excellent Quality Level (QL7-E), was assigned to the examined TM products. The tested TM products presented in this paper, reached at least the minimum quality level (QL1-B). The TM-QC process allowed the definition of standardized quality levels for the TM products/services and the proposed procedures should be useful for promoting the using of standardized TM applications, so to speed up the integration process into the National Health Service.

Experience at Italian National Institute of Health in the quality control in telemedicine: tools for gathering data information and quality assessing

The authors proposed a set of tools and procedures to perform a Telemedicine Quality Control process (TM-QC) to be submitted to the telemedicine (TM) manufacturers. The proposed tools were: the Informative Questionnaire (InQu), the Classification Form (ClFo), the Technical File (TF), the Quality Assessment Checklist (QACL). The InQu served to acquire the information about the examined TM product/service; the ClFo allowed to classify a TM product/service as belonging to one application area of TM. The TF was intended as a technical dossier of product and forced the TM supplier to furnish the only requested documentation of its product, so to avoid redundant information. The QACL was a checklist of requirements, regarding all the essential aspects of the telemedical applications, that each TM products/services must be met. The final assessment of the TM product/service was carried out via the QACL, by computing the number of agreed requirements: on the basis of this computation, a Quality Level (QL) was assigned to the telemedical application. Seven levels were considered, ranging from the Basic Quality Level (QL1-B) to the Excellent Quality Level (QL7-E). The TM-QC process resulted a powerful tool to perform the quality control of the telemedical applications and should be a guidance to all the TM practitioners, from the manufacturers to the expert evaluators. The quality control process procedures proposed thus could be adopted in future as routine procedures and could be useful in the assessing the TM delivering into the National Health Service versus the traditional face to face healthcare services.

The immune response of women with prolonged exposure to electromagnetic fields produced by radiotelevision broadcasting stations

Twelve women, five of them housewives, exposed in their residences to electromagnetic fields (EMFs)emitted by radio-television broadcasting stations for a mean period of 13 years, were investigated. The EMFs in the balconies of the homes were (mean + S.D.) 4.3 + 1.4 V/m in the year 2000 and 3.7 + 1.3 V/m in 2005, while the exposure in the nearby area was <2.0 V/m. The EMF exposed women showed in 2000 reduced blood NK lymphocytes as well as PHA stimulated PBMC proliferation and IL-2 and IFN-gamma release. In the year 2005, the EMF exposed women and 48 control women with similar ages(mean 43 years), smoking habits, atopy and social level were investigated. State (temporary) and trait(tendency of the personality) anxiety were determined by STAI I and II, respectively. Blood cytotoxic activity and lymphocyte subsets were also determined. The ratio STAI I/STAI II of the EMF exposed group was lower than that of the control group. The blood cytotoxic activity of the exposed women was lower (p<0.01), percent of B CD45+-CD19+ lymphocytes higher and percent of CD45+-CD3+-CD8+ cells lower (p<0.05). Moreover, cytotoxic activity/CD45+-CD16+-56+ NK lymphocytes of the controls was negatively correlated with STAI I and STAI II (p<0.001). In conclusion, this study demonstrates reduced blood cytotoxic activity and increased trait anxiety in relation to state anxiety in EMF exposed women. An effect of EMFs on immune functions, in part mediated by nervous mechanisms, may be hypothesized. However, the influence of lifestyle may not be excluded.

Chromosomal analysis of Astyanax fasciatus (PISCES, CHARACIDAE) from the Araguari river, Uberlândia, MG, Brazil

The genus Astyanax is one of the most numerous of the family Characidae, comprising a large number of similar-shaped species, but displaying innumerable karyotypic variations in its chromosome number and/or structure. The literature describes A. fasciatus populations with diploid chromosome numbers varying from 2n = 45 to 2n = 48. In this study, A. fasciatus specimens captured in the Araguari River (Alto Paraná basin) were cytogenetically characterized, revealing a diploid chromosome number of 2n = 46. The nucleolar organizing regions (NORs), detected with silver nitrate staining, showed a multiple system with two pairs of marked chromosomes. These findings are congruent with those of other studies involving populations of the same species.

Diffusive and convective transport through hollow fiber membranes for liver cell culture

For an efficient membrane bioreactor design, transport phenomena determining the overall mass flux of metabolites, catabolites, cell regulatory factors, and immune-related soluble factors, need to be clarified both experimentally and theoretically. In this work, experiments and calculations aimed at discerning the simultaneous influence of both diffusive and convective mechanisms to the transport of metabolites. In particular, the transmembrane mass flux of glucose, bovine serum albumin (BSA), APO-transferrin, immunoglobulin G, and ammonia was experimentally measured, under pressure and concentration gradients, through high-flux microporous hydrophilic poly-ether-sulphone (PES-HFMs) and poly-sulphone hollow fiber membranes (PS-HFMs). These data were analyzed by means of a model based on the mechanism of capillary pore diffusion, assuming that solute spherical molecules pass through an array of solvent-filled cylindrical pores with a diffusive permeation corrected for friction and steric hindrances. Additionally, resistances to the mass transfer were taken into account. Convective permeation data were discussed in terms of morphological properties of the polymeric membranes, molecular Stokes radius, and solute-membrane interactions according to information given by contact angle measurements. The observed steady-state hydraulic permeance of PS-HFMs was 0.972 L/m2hmbar, about 15.6-fold lower than that measured for PES-HFMs (15.2 L/m2h); in general, PS-HFMs provided a significant hindrance to the transport of target species. Diffusion coefficients of metabolites were found to be similar to the corresponding values in water through PES-HFMs, but significantly reduced through PS-HFMs (D(Glucose)(Membrane)=2.8x10(-6)+/-0.6x10(-6)cm2/s, D(BSA)(Membrane)=6.4 x 10(-7)+/-1 x 10(-7)cm(/s, D(Apotransferrin)(Membrane)=2.3 x 10(-7)+/-0.25 x 10(-7)cm2/s).

Epidemiological, clinical and therapeutic features of AIDS-related Mycobacterium kansasii infection during the HIV pandemic: an 11-year follow-up study

OBJECTIVES

Optimal diagnosis and timely treatment of atypical mycobacteriosis, and especially Mycobacterium kansasii disease, remain a serious challenge for clinicians engaged in the management of the immunocompromised host.

METHODS AND RESULTS

From more than 2700 hospitalizations (over 1800 patients) attributable to HIV-associated disorders over an 11-year period, 12 patients were found to have a confirmed M. kansasii infection. This reflects the recent reduction in the frequency of this HIV-related complication, which virtually disappeared after the introduction of potent antiretroviral combinations in 1996. In the early 1990s, the lack of effective antiretroviral regimens made frequent the association with AIDS, a mean CD4 lymphocyte count of nearly 20 cells/microL, and an extremely variable chest X-ray features. The recent detection of a further case was attributable to late recognition of very advanced HIV disease, complicated by multiple opportunistic disorders.

CONCLUSIONS

Mycobacterium kansasii respiratory or disseminated infection continues to occur, and poses diagnostic problems in terms of late or missed identification as a result of slow culture and frequently concurrent opportunistic disease. Serious therapeutic difficulties also arise from the unpredictable in vitro antimicrobial susceptibility profile of these organisms, and from the need to start an effective combination therapy that does not interfere with other medications as soon as possible.

PTH and phospholipase A2 in the aging process of intestinal cells

In this study we analyzed, for the first time, alterations in phospholipase A2 (PLA2) activity and response to parathyroid hormone (PTH) in rat enterocytes with aging. We found that PTH, rapidly stimulate arachidonic acid (AA) release in rat duodenal cells (+1- to 2-fold), an effect that is greatly potentiated by aging (+4-fold). We also found that hormone-induced AA release in young animals is Ca2+-dependent via cPLA2, while AA released by PTH in cells from aged rats is due to the activation of cPLA2 and the Ca2+-independent PLA2 (iPLA2). In enterocytes from 3 months old rats, PTH induced, in a time and dose-dependent fashion, the phosphorylation of cPLA2 on serine 505, with a maximum at 10 min (+7-fold). Basal levels of cPLA2 serine-phosphorylation were higher in old enterocytes, affecting the hormone response which was greatly diminished (+2-fold at 10 min). cPLA2 phosphorylation impairment in old animals was not related to changes of cPLA2 protein expression and did not explain the substantial increase on PTH-induced AA release with aging, further suggesting the involvement of a different PLA2 isoform. Intracellular Ca2+ chelation (BAPTA-AM, 5 microM) suppressed the serine phosphorylation of cPLA2 in both, young and aged rats, demonstrating that intracellular Ca2+ is required for full activation of cPLA2 in enterocytes stimulated with PTH. Hormone effect on cPLA2 was suppressed to a great extent by the MAP kinases ERK 1 and ERK2 inhibitor, PD 98059 (20 microM), the cAMP antagonist, Rp-cAMP, and the PKC inhibitor Ro31820 both, in young and aged animals. Enterocytes exposure to PTH also resulted in phospho-cPLA2 translocation from cytosol to nuclei and membrane fractions, where phospholipase substrates reside. Hormone-induced enzyme translocation is also modified by aging where, in contrast to young animals, part of phospho-cPLA2 remained cytosolic. Collectively, these data suggest that PTH activates in duodenal cells, a Ca2+-dependent cytosolic PLA2 and attendant AA release and that this activation requires prior stimulation of intracellular ERK1/2, PKA, and PKC. cPLA2 is the major enzyme responsible for AA release in young enterocytes while cPLA2 and the Ca2+-independent iPLA2, potentiate PTH-induced AA release in aged cells. Impairment of PTH activation of PLA2 isoforms upon aging may result in abnormal hormone regulation of membrane fluidity and permeability and thereby affecting intestinal cell membrane function.

Infective endocarditis from Enterococcus faecalis complicating colonoscopy in Heyde's syndrome

A case of infective endocarditis from Enterococcus faecalis after colonoscopy in a patient with aortic stenoinsufficiency and bleeding intestinal angiodysplasia (Heyde's syndrome) is reported.A 77 year old man with aortic stenoinsufficiency presented with enterorrhagia and underwent a colonoscopy, which showed normal findings. Fifteen days later he developed a moderate degree of fever. Blood cultures were positive for E faecalis. An echocardiogram showed aortic valve vegetations, and infective endocarditis was diagnosed and successfully treated by antibiotics. Some months later, intestinal bleeding recurred and intestinal resection was performed. Histopathology showed angiodysplasia. In patients with Heyde's syndrome antibiotic prophylaxis should be considered before colonoscopy.

New modified polyetheretherketone membrane for liver cell culture in biohybrid systems: adhesion and specific functions of isolated hepatocytes

There has been growing interest in innovative materials with physico-chemical properties that provide improved blood/cell compatibility. We propose new polymeric membranes made of modified polyetheretherketone (PEEK-WC) as materials with potential for use in biohybrid devices. PEEK-WC exhibits high chemical, thermal stability and mechanical resistance. Owing to its lack of crystallinity this polymer can be used for preparing membranes with cheap and flexible methods. We compared the properties of PEEK-WC membranes to polyurethane membranes prepared using the same phase inverse technique and commercial membranes. The physico-chemical properties of the membranes were characterised by contact angle measurements. The different parameters acid (gamma+), base (gamma-) and Lifshitz-van der Waals (gammaLW) of the surface free energy were calculated according to Good-van Oss's model. We evaluated the cytocompatibility of PEEK-WC membranes by culturing hepatocytes isolated from rat liver. Cell adhesion and metabolic behaviour in terms of ammonia elimination, urea synthesis and protein synthesis were evaluated during the first days of culture. Liver cells adhered and formed three-dimensional aggregates on the most tested membranes. PEEK-WC membranes promoted hepatocyte adhesion most effectively. Urea synthesis, ammonia elimination and protein synthesis improved significantly when cells adhered to PEEK-WC membrane. The considerable metabolic activities of cells cultured on this membrane confirmed the good structural and physico-chemical properties of the PEEK-WC membrane that could be a promising biomaterial for cell culture in biohybrid devices.

Novel PEEK-WC membranes with low plasma protein affinity related to surface free energy parameters

There has been growing interest in innovative materials with specific physico-chemical properties that provide an improved blood/cell compatibility. In this paper we evaluated the performance of new membranes prepared from a modified polyetheretherketone (PEEK-WC) contacting human plasma proteins. These membranes were prepared by using the phase inversion technique. Membrane wettability and affinity to proteins were evaluated by means of contact angle experiments, roughness measurements, and quantitative UV analysis. The energy parameters of membrane surfaces were determined according to Good, van Oss and Chaudhury's theory. The extent of human albumin, fibrinogen and immunoglobulin G adsorption was related to quantitative expressions of the membrane surface hydrophilicity: the base parameter of surface free energy and the free energy of interfacial interaction. The performance of PEEK-WC membranes was compared to that of commercial membranes, which conventionally are used in biomedical applications. The experimental results showed a reduction of protein adsorption on PEEK-WC membranes with respect to other commercial membranes. The low protein affinity of PEEK-WC membranes is due to the intrinsic physico-chemical characteristics of the polymeric material which makes these membranes interesting for potential use in biomedical applications.

1alpha,25(OH)2D3 and parathyroid hormone (PTH) signaling in rat intestinal cells: activation of cytosolic PLA2

In the current study, we have probed the role of cytosolic phospholipase A2 (cPLA2) activity in the cellular response to the calciotropic hormones, 1alpha,25,dihydroxy-vitamin D(3) [1alpha,25(OH)(2)D(3)] and PTH. Stimulation of rat enterocytes with either hormone, increased release of arachidonic acid (AA) 3H-AA] one-two fold in a concentration and time-dependent manner. The effect of either hormone on enterocytes was totally reduced by preincubation with the intracellular Ca(2+) chelator BAPTA-AM (5 microM), suggesting that the release of AA following cell exposure to the calciotropic hormones occurs mainly through a Ca(2+)-dependent mechanism involving activation of Ca(2+)-dependent cPLA2. Calciotropic homone stimulation of rat intestinal cells increases cPLA2 phosphorylation (three to four fold). This effect was decreased by PD 98059 (20 microM), a MAP kinase inhibitor, indicating that this action is, in part, mediated through activation of the MAP kinases ERK 1 and ERK2. Enterocytes exposure to 1alpha,25(OH)(2)D(3) (1nM) or PTH (10 nM) also resulted in P-cPLA2 translocation from cytosol to nuclei and membrane fractions, where phospholipase subtrates reside. Collectively, these data suggest that PTH and 1alpha,25(OH)(2)D(3) activate in duodenal cells, a Ca(2+)-dependent cytosolic PLA2 and attendant arachidonic acid release and that this activation requieres prior stimulation of intracellular ERK1/2. 1alpha,25(OH)(2)D(3) and PTH modulation of cPLA2 activity may change membrane fluidity and permeability and thereby affecting intestinal cell membrane function.

New instrumental set for the assessment of the hand functionality

Hand motor deficits have been widely investigated, and several devices have been proposed for the selective and accurate study of specific hand motor tasks. Most studies have focused on the four, long fingers. The thumb function, although extremely important for the performance of most daily activities involving the hand, has scarcely been documented. A set of general-purpose, instrumental measuring devices has been designed and constructed at the authors' laboratory to measure and monitor the force each finger exerts separately, under isometric conditions, during pressing tasks. More generally, it is meant for the functional evaluation of the normal hand in different postures, but it also provides reliable measurements of the injured or deformed hand. The instrumental set is suitable for both biomechanical research and clinical applications. Effectively integrated with a visual feedback tool, it could be exploited in delivering and monitoring custom-designed rehabilitation programmes. The characteristics of the force transducers (range 0-100 N) were: inter-axis crosstalk < 4%; non-linearity < +/- 0.4% f.s.; hysteresis < 0.3% f.s.; overall accuracy +/- 1% f.s. The overall measurement system resolution was better than 0.1 N, and the keys response to the mechanical shock (acquired at 10 kHz) showed a resonance frequency of about 1 kHz. It was observed that the thumb contributed more than 30% of the overall pressing force.

Transgenic mice with dominant negative PKC-theta in skeletal muscle: a new model of insulin resistance and obesity

Protein kinase C theta (PKC-theta) is the PKC isoform predominantly expressed in skeletal muscle, and it is supposed to mediate many signals necessary for muscle histogenesis and homeostasis, such as TGFbeta, nerve-dependent signals and insulin. To study the role of PKC-theta in these mechanisms we generated transgenic mice expressing a "kinase dead" mutant form of PKC-theta (PKC-thetaK/R), working as "dominant negative," specifically in skeletal muscle. These mice are viable and fertile, however, by the 6-7 months of age, they gain weight, mainly due to visceral fat deposition. Before the onset of obesity (4 months of age), they already show increased fasting and fed insulin levels and reduced insulin-sensitivity, as measured by ipITT, but normal glucose tolerance, as measured by ipGTT. After the 6-7 months of age, transgenic mice develop hyperinsulinemia in the fasting and fed state. The ipGTT revealed in the transgenic mice both hyperglycemia and hyperinsulinemia. At the molecular level, impaired activation of the IR/IRS/PI3K pathway and a significant decrease both in the levels and in insulin-stimulated activation of the serine/threonine kinase Akt were observed. Taken together these data demonstrate that over-expression of dominant negative PKC-theta in skeletal muscle causes obesity associated to insulin resistance, as demonstrated by defective receptor and post-receptorial activation of signaling cascade.

Characterization of PTH/PTHrP receptor in rat duodenum: effects of ageing

In rat enterocytes, signaling through the parathyroid hormone (PTH)/PTH-related peptide receptor type 1(PTHR1) includes stimulation of adenylyl cyclase, increases of intracellular calcium, activation of phospholipase C, and the MAP kinase pathway, mechanisms that suffer alterations with ageing. The purpose of this study was to evaluate whether an alteration at the level of the PTH receptor (PTHR1) is the basis for impaired PTH signaling in aged rat enterocytes. Western Blot analysis with a specific monoclonal anti-PTHR1 antibody revealed that a 85 kDa PTH binding component, the size expected for the mature PTH/PTHrP receptor, localizes in the basolateral (BLM) and brush border (BBM) membranes of the enterocyte, being the protein expression about 7-fold higher in the BLM. Two other bands of 105 kDa (corresponding to highly glycosylated, incompletely processed receptor form) and 65 kDa (proteolytic fragment) were also seen. BLM PTHR1 protein expression significantly decreases with ageing, while no substantial decrease was observed in the BBM from old rats. PTHR1 immunoreactivity was also present in the nucleus where PTHR1 protein levels were similar in enterocytes from young and aged rats. Immunohistochemical analysis of rat duodenal sections showed localization of PTHR1 in epithelial cells all along the villus with intense staining of BBM, BLM, and cytoplasm. The nuclei of these cells were reactive to the PTHR1 antiserum, but not all cells showed the same nuclear staining. The receptor was also detected in the mucosae lamina propria cells, but was absent in globets cells from epithelia. In aged rats, PTHR1 immunoreactivity was diffused in both membranes and cytoplasm and again, PTH receptor expression was lower than in young animals, while the cell nuclei showed a similar staining pattern than in young rats. Ligand binding to PTHR1 was performed in purified BLM. rPTH(1-34) displaced [I(125)]PTH(1-34) binding to PTHR1 in a concentration-dependent fashion. In both, aged (24 months) and young (3 months) rats, binding of [I(125)]PTH was characterized by a single class of high-affinity binding sites. The affinity of the receptor for PTH was not affected by age. The maximum number of specific PTHR1 binding sites was decreased by 30% in old animals. The results of this study suggest that age-related declines in PTH regulation of signal transduction pathways in rat enterocytes may be due, in part, to the loss of hormone receptors.

Involvement of PI3-kinase and its association with c-Src in PTH-stimulated rat enterocytes

Phosphoinositide-3-kinase (PI3K) is a lipid kinase, which phosphorylates the D3 position of phosphoinositides, and is known to be activated by a host of protein tyrosine kinases. PI3K plays an important role in mitogenesis in several cell systems. However, whether parathyroid hormone (PTH) affects the activity and functional roles of PI3K in intestinal cells remain to be determined. The objective of this study was to identify and characterize the PI3K pathway, and its relation to other non-receptor tyrosine kinases in mediating PTH signal transduction in rat enterocytes. PTH dose- and time-dependently increased PI3K activity with a peak occurring at 2 min. The tyrosine kinase inhibitor genistein, c-Src inhibitor PP1 and two structurally different inhibitors of PI3K, LY294002 and wortmannin, suppressed PI3K activity dependent on PTH. Co-immunoprecipitation analysis showed a constitutive association between c-Src and PI3K, which was enhanced by PTH treatment, suggesting that the cytosolic tyrosine kinase forms an immunocomplex with PI3K probably via the N-SH2 domain of the p85alpha regulatory subunit. In response to PTH, tyrosine phosphorylation of p85alpha was enhanced, effect that was abolished by PP1, the inhibitor of c-Src kinase. PTH causes a rapid (0.5-5 min) phosphorylation of Akt/PKB, effect that was abrogated by PI3K inhibitors, indicating that in rat enterocytes, PI3K is an upstream mediator of Akt/PKB activation by PTH. We report here that PI3K is also required for PTH activation of the mitogen-activated protein kinases ERK1 and ERK2. Taken together, the present study demonstrate, for the first time, that PTH rapidly and transiently stimulates PI3K activity and its down effector Akt/PKB in rat enterocytes playing c-Src kinase a central role in PTH-dependent PI3K activation and that PI3K signaling pathway contributes to PTH-mediated MAPK activation.

Effect of ageing in the early biochemical signals elicited by PTH in intestinal cells

In previous work, we have demonstrated that rPTH(1-34) increases cytoplasmic calcium concentration ([Ca(2+)](i)) in isolated rat enterocytes. In the present study, we have identified the sources of PTH-mediated increase in [Ca(2+)](I) and the implication of Ca(2+) on hormone early signals in enterocytes isolated from young (3-month-old) and aged (24-month-old) rats. In young enterocytes, PTH raised [Ca(2+)](i) in a dose-dependent manner (1 pM-100 nM). In cells from aged rats, hormone concentrations higher than physiological (>/=1 nM) were required to observe significant increases in [Ca(2+)](i). Phospholipase C (PLC) inhibitors blocked the initial acute elevation of the [Ca(2+)](i) biphasic response to PTH of young enterocytes while in old cells, no effects were observed. The voltage-dependent calcium-channel blocker (VDCC), nitrendipine, suppressed PTH-dependent changes of the sustained [Ca(2+)](i) phase in young and aged animals. In this study, we analysed, for the first time, alterations in phosphatidylinositol 3-kinase (PI3K) activity and response to PTH in rat enterocytes with ageing. Basal PI3K activity was significantly modified by ageing. Acute treatment with 10(-8) M PTH increased enzyme activity, with a maximun at 2 min (+3-fold) in young rats and only elevated by less than 1-fold basal PI3K activity in aged animals. Hormone-induced tyrosine phosphorylation of p85alpha, the regulatory subunit of PI3K, as well as the phosphorylation on Thr(308) of its downstream effector Akt/PKB was evident in enterocytes from 3-month-old rats, whereas it was greatly reduced in the cells from 24-month-old animals. Intracellular Ca(2+) chelation (BAPTA-AM, 5 microM) affected the tyrosine phosphorylation of p85alpha and inhibited PTH-dependent PI3K activation by 75% in young rats and completely abolished the enzyme activity in aged animals, demonstrating that Ca(2+) is required for full activation of PI3K in enterocytes stimulated with PTH. The Thr phosphorylation of PI3K downeffector, Akt/PKB, was also fully dependent on Ca(2+). Taken together, these results suggest that PTH regulation of enterocyte [Ca(2+)](i) involves Ca(2+) mobilization from IP(3)-sensitive stores and the influx of the cation from the extracellular milieu, the former pathway being blunted during ageing. The data also indicates a positive role for intracellular calcium in one of the early signals of PTH in rat enterocytes, the activation of PI3K, and that hormone regulation of PI3K activity and Akt/PKB phosphorylation on Thr(308) is impaired with ageing.

Two polyclonal antisera detect different AGE epitopes in human plasma samples

Advanced glycation end products (AGEs), involved in the pathogenesis of diabetic complications, comprise a series of related chemical structures which might possess dissimilar immunogenic characteristics. In this study the levels of AGE in plasma samples from normal subjects (N=41) and diabetic patients (N=44) were measured by ELISA using two polyclonal antisera (named CF5 and CF199, respectively, and immunologically characterized) raised using two different immunogens and immunization techniques. Age levels were significantly higher in diabetic than in normal plasma samples (P<0.0001) with both antisera. However, CF199 detected higher AGE levels than CF5 both in normal (P<0.0001) and diabetic (P<0.005) samples. Pre-incubation with AGE-bovine serum albumin (BSA) caused the loss of most the reactivity of both antisera. Pre-incubation with carboxy-methyl-lysine-BSA (an oxidation-derived AGE) induced the loss of nearly all CF5 reactivity while CF199 retained a significant amount of activity against AGE antigens. Moreover, CF5 lost over 90% of its reactivity against BSA incubated with high glucose under non-oxidative conditions, suggesting its recognition of mainly oxidation-derived AGE epitopes. The different AGE levels measured by the two antisera suggests, therefore, that one single antiserum is unable to recognize all the various AGE epitopes which might be present, at any time, in tissues and body fluids in health and disease.