Exploring the potentialities of comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry to distinguish bivalve species: Comparison of two clam species (Venerupis decussata and Venerupis philippinarum)

Metabolomics represents an emerging topic that can be valuable in the knowledge of organism responses to different stimuli. Metabolomic studies of bivalves may reveal the constraints they are subjected to, and may help clarifying the functions most affected and the tolerance mechanisms triggered. In response to this approach, two-dimensional gas chromatography-time of flight mass spectrometry (GC×GC-ToFMS) combined with headspace solid phase microextraction (HS-SPME) was applied, for the first time to our knowledge, to the untargeted and comprehensive study of the volatile composition of clam species. Firstly, experimental parameters that influence the SPME extraction efficiency were evaluated: sample preparation mode, sample volume and SPME fiber coating. Taking into account the results from the optimization step, the metabolomic profiles were performed using 1 ml of clam soft tissues homogenized with N2 and diluted in deionised water (1:2, w/v), using the PDMS/DVB fiber coating. From a total of more than 200 compounds detected per sample, 63 were tentatively identified and distributed over the chemical families of hydrocarbons, ketones, aldehydes, alcohols, and terpenoids, which seems to arise from clams own metabolism, and/or from their activity as filter-feeders. The potential of this methodology to discriminate close related species was explored by comparing the volatile profiles of Venerupis philippinarum and Venerupis decussata from Ria de Aveiro, two clams belonging to the same genus. Both species experience different environment conditions, and physiological and biochemical characteristics, which may explain the observed differentiation between their metabolic profiles. To our knowledge, this is the most detailed information available so far about clam volatile composition, which represents a valuable data for future advanced studies in the ecology, toxicology and physiology of bivalves based on clams fingerprinting.

Biochemical effects of acetaminophen in aquatic species: edible clams Venerupis decussata and Venerupis philippinarum

Acetaminophen (paracetamol) is one of the most used pharmaceutical drugs, due to its antipyretic and analgesic properties that turn it into a primary choice in varied pathologies and conditions. However, and despite its massive use, acetaminophen is not exempt of adverse effects, especially when administered in over dosage, which are related to the formation of toxic metabolites by oxidative pathways. It is thus possible to observe that toxicity caused by acetaminophen is usually mediated by reactive oxygen species and can result in multiple effects, ranging from protein denaturation to lipid peroxidation and DNA damage. The occurrence of acetaminophen has been reported in the aquatic environment, being important to address the potential exertion of toxic effects on nontarget environmentally exposed organisms. The present study intended to characterize the effects of acute acetaminophen exposure on physiological traits (antioxidant defense, oxidative damage) of two species of bivalves, namely, the edible clams Venerupis decussata and Venerupis philippinarum. Results showed a significant increase in all oxidative stress biomarkers, evidencing the bioactivation of acetaminophen into a deleterious prooxidant, triggering the onset of deleterious effects. Furthermore, strong interspecific differences were observed among responses of the two tested species, which was a major issue due to intrinsic ecological implications when one considers that both species share the same habitat.

Consumption of Ruditapes philippinarum and Ruditapes decussatus: comparison of element accumulation and health risk

Ruditapes philippinarum, a species native from the Indo-Pacific region, was introduced in Europe at the beginning of the 1970s for culture purposes, leading to a massive decrease of the native species Ruditapes decussatus and a high increase of R. philippinarum yields in Europe. Bivalves can accumulate high amounts of metals and thus easily reach concentrations that are toxic not only to themselves but also to consumers. Since differences in the accumulation of pollutants may exist between bivalve species, different health risks may be overcome. For this reason, the level of metals in seafood raises public health concerns, and international organisations like European Food Safety Authority, United States Food and Drug Administration, and Food Standards Australia and New Zealand (FSANZ) set maximum levels (MLs), above which edible seafood cannot be marketed. In order to evaluate the risk associated with the consumption of R. philippinarum and R. decussatus, both clam species were collected in the same site in Ria de Aveiro and the concentration of eight elements determined in organisms before and after a 48-h depuration period. Results evidence that even at low contaminated areas, the MLs for some elements can easily be achieved. The concentrations of As were above the reference values for FSANZ, and the provisional tolerable weekly intake (PTWI) is exceeded for As when more than 0.5 kg of R. decussatus and 0.9 kg of R. philippinarum clam flesh is consumed, in 1 week, by an adult (70 kg). When comparing with other systems worldwide, consumers of depurated clams from this coastal system have a similar or lower risk of exceeding the PTWI for Cd, As, Pb, and Hg. The recently introduced clam, R. philippinarum, accumulates lower amounts of the most health-threatening elements (less than 71 % of Cd, 40 % of As, and 20 % of Hg) than the native R. decussatus, except for Pb. R. philippinarum also reduces more the element burden when subjected to depuration than R. decussatus. Moreover, R. philippinarum allocates a lower proportion of the accumulated elements in the soluble fraction, where they are readily available. Thus, it is safer to consume R. philippinarum than R. decussatus, except when clams come from areas heavily polluted by Pb.

Adult circumcision and male sexual health: a retrospective analysis

We aimed to evaluate possible associations of circumcision with several sexual dysfunctions and to identify predictors for the development of these outcomes post-operatively. Telephone surveys about sexual habits and dysfunctions before and after intervention were conducted post-operatively to patients that underwent circumcision in Centro Hospitalar Vila Nova de Gaia/Espinho during 2011. McNemar test was used for a matched-pairs analysis of pre- and post-operative data. Odds ratios, adjusted in a multivariate analysis, explored predictors of de novo sexual dysfunctions after circumcision. With intervention, there was an increase in frequency of erectile dysfunction (9.7% versus 25.8%, P = 0.002) and delayed orgasm (11.3% versus 48.4%, P < 0.001), and a significant symptomatic improvement in patients with pain with intercourse (50.0% versus 6.5%, P < 0.001). Significant predictors for de novo erectile dysfunction were diabetes mellitus (OR 9.81, P = 0.048) and lack of sexual desire (OR 8.76, P = 0.028). Less than three sex partners (OR 7.04, P = 0.007) and low sexual desire (OR 7.49, P = 0.029) were significant predictors for de novo delayed orgasm.

Are metallothioneins equally good biomarkers of metal and oxidative stress?

Several researchers investigated the induction of metallothioneins (MTs) in the presence of metals, namely Cadmium (Cd). Fewer studies observed the induction of MTs due to oxidizing agents, and literature comparing the sensitivity of MTs to different stressors is even more scarce or even nonexistent. The role of MTs in metal and oxidative stress and thus their use as a stress biomarker, remains to be clearly elucidated. To better understand the role of MTs as a biomarker in Cerastoderma edule, a bivalve widely used as bioindicator, a laboratory assay was conducted aiming to assess the sensitivity of MTs to metal and oxidative stressors. For this purpose, Cd was used to induce metal stress, whereas hydrogen peroxide (H2O2), being an oxidizing compound, was used to impose oxidative stress. Results showed that induction of MTs occurred at very different levels in metal and oxidative stress. In the presence of the oxidizing agent (H2O2), MTs only increased significantly when the degree of oxidative stress was very high, and mortality rates were higher than 50 percent. On the contrary, C. edule survived to all Cd concentrations used and significant MTs increases, compared to the control, were observed in all Cd exposures. The present work also revealed that the number of ions and the metal bound to MTs varied with the exposure conditions. In the absence of disturbance, MTs bound most (60-70 percent) of the essential metals (Zn and Cu) in solution. In stressful situations, such as the exposure to Cd and H2O2, MTs did not bind to Cu and bound less to Zn. When organisms were exposed to Cd, the total number of ions bound per MT molecule did not change, compared to control. However the sort of ions bound per MT molecule differed; part of the Zn and all Cu ions where displaced by Cd ions. For organisms exposed to H2O2, each MT molecule bound less than half of the ions compared to control and Cd conditions, which indicates a partial oxidation of thiol groups in the cysteine residues through ROS scavenging. The present results suggest that MTs are excellent markers of metal stress, but not of oxidative stress.

Ruditapes decussatus and Ruditapes philippinarum exposed to cadmium: toxicological effects and bioaccumulation patterns

Since differences in metal accumulation may exist between bivalve species, the aim of this study was to assess the impact of cadmium (Cd) on Ruditapes decussatus and Ruditapes philippinarum. For this, the Cd accumulation, mortality rates and biochemical responses were analysed in the two species after 5days of exposure, under laboratory-controlled conditions. The concentration of Cd that caused 50% of mortality on clams was two-times higher in R. decussatus than in R. philippinarum. For both species, higher percentage (84.5-98.2%) of the Cd was in the insoluble fraction, but the Cd concentration in solution was 3 to 8 times higher in R. decussatus. Nevertheless, R. philippinarum presented higher oxidative stress and higher CAT activity. The paradox observed between the two clams can be explained by the higher capacity of R. decussatus to increase the expression of MTs when exposed to Cd.

Role of ecto-NTPDases on UDP-sensitive P2Y(6) receptor activation during osteogenic differentiation of primary bone marrow stromal cells from postmenopausal women

This study aimed at investigating the expression and function of uracil nucleotide-sensitive receptors (P2Y(2), P2Y(4), and P2Y(6)) on osteogenic differentiation of human bone marrow stromal cells (BMSCs) in culture. Bone marrow specimens were obtained from postmenopausal female patients (68 ± 5 years old, n = 18) undergoing total hip arthroplasty. UTP and UDP (100 µM) facilitated osteogenic differentiation of the cells measured as increases in alkaline phosphatase (ALP) activity, without affecting cell proliferation. Uracil nucleotides concentration-dependently increased [Ca(2+)](i) in BMSCs; their effects became less evident with time (7 > 21 days) of the cells in culture. Selective activation of P2Y(6) receptors with the stable UDP analog, PSB 0474, mimicked the effects of both UTP and UDP, whereas UTPγS was devoid of effect. Selective blockade of P2Y(6) receptors with MRS 2578 prevented [Ca(2+)](i) rises and osteogenic differentiation caused by UDP at all culture time points. BMSCs are immunoreactive against P2Y(2), P2Y(4), and P2Y(6) receptors. While the expression of P2Y(6) receptors remained fairly constant (7∼21 days), P2Y(2) and P2Y(4) became evident only in less proliferative and more differentiated cultures (7 < 21 days). The rate of extracellular UTP and UDP inactivation was higher in less proliferative and more differentiated cell populations. Immunoreactivity against NTPDase1, -2, and -3 rises as cells differentiate (7 < 21 days). Data show that uracil nucleotides are important regulators of osteogenic cells differentiation predominantly through the activation of UDP-sensitive P2Y(6) receptors coupled to increases in [Ca(2+)](i) . Endogenous actions of uracil nucleotides may be balanced through specific NTPDases determining whether osteoblast progenitors are driven into proliferation or differentiation.

Looking for suitable biomarkers in benthic macroinvertebrates inhabiting coastal areas with low metal contamination: comparison between the bivalve Cerastoderma edule and the Polychaete Diopatra neapolitana

Metals accumulated in marine sediments are often a threat to benthic communities. With the recognized importance and wide use of stress biochemical responses as indicators of metal contamination it becomes essential to compare these markers between different species and verify their ubiquity and accuracy. Using wild Diopatra neapolitana and Cerastoderma edule, collected at several areas differing in metal contamination, this study aimed to assess the use of these two macrobenthic species as sentinel organisms and to determine the applicability of currently used biomarkers in benthic species exposed to a range of low metal and As concentrations. Total metal accumulation and intracellular partitioning was analyzed and metal-induced alterations were assessed through the analysis of several biochemical parameters in both organisms, including stress-induced reactive oxygen species (ROS), lipid peroxidation and protein content, the activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and of glutathione S-transferase (GST). Metal chelation by Metallothioneins (MTs) was also determined. Results revealed that D. neapolitana accumulated higher levels of metals when compared to C. edule, independently of the sediment concentration. Results also showed strong species-specific responses to metals and differences in the ability to sequester metals. Overall, C. edule showed to be more efficient metal chelator and precipitatior than D. neapolitana, which was less tolerant and presented oxidative stress. MTs proved to be a good predictor of metal accumulation in both species, even under low metal exposures. On the other hand, lipid peroxidation was a good indicator of oxidative damage, only observed in D. neapolitana, which was a result of higher metal retention in the soluble fraction.

P3-07-37: Clinical Characteristics and Treatment of Brazilian Women with Breast Cancer at Public and Private Institutions

Background: Breast cancer is the most common type of cancer among Brazilian women with almost 50.000 new cases per year. There are few data regarding the clinical presentation, treatment and specially outcome of this population. Brazilian health system is composed by Public institutions (Pu); Private centers (Pr) and some institutions that assist both Public and Private patients (PuPr).

Material and Methods: We collected data from 17 cancer centers distributed throughout Brazil among Pu; Pr and PuPr centers. We've analyzed data from 1-clinical characteristics, 2- pathologic characteristics and 3-type of treatment received among 2435 patients from May 2008 to May 2009.

Results: Mean age at diagnosis was 53 years, with about 30% below age 50. Most of the cases were Invasive Ductal Cancer (83%). Stage 0 was seen in 3.2%, Stage I in 21,8%, Stage II in 46,6%, Stage 3 in 24,6% and Stage IV in 3,9 %. Clinical Stage III + IV was seen in 18,5% of the Pu institutions, only 3,7% of the Pr ones and about 6,2% among those PuPr. Hormone receptors were positive in 55%. Her-2 was overexpressed in 27,3% of the patients, and triple negative were seen in 11,6%. Most of the patients were submitted to surgery (92,9%). In Pu institutions only 36% of the patients were submitted to Breast Conserving Surgery (BCS) and in the Pr institutions 49,4% of the patients were submitted to BCS and in the PuPr 47%. Breast reconstruction was made in 15,8% and did not differ between Pu and Pr institutions. Sentinel node biopsy was done in 30,6% of the patients (26,8% of the patients from the Pr institutions and 26,8% of the Pu ones and 33% among PuPr). Neoadjuvant treatment was done in 21,5% of the patients (Pu=27,2%; Pr=13,9% and PuPr 13,2%). Most of this neoadjuvant treatment was chemotherapy (93,8%) and only 4,3% was hormonetherapy (HT). 30% of the patients received AC, 41% A+taxane and 18,9% FAC/FEC. Besides we have almost 30% of Her-2 overexpressed only 1,1% of the patients received trastuzumab in the neoadjuvant setting. Tamoxifen was used in 48,3% when neoadjuvant HT was done, and aromatase inhibitor (AI) was used in 34,5%. Most of the patients received any kind of adjuvant treatment (89,2%). Chemotherapy was done in 76,6% and hormonetherapy in 69,8%. When chemotherapy was used the preference regiment was FAC/FEC (27,3%), followed by CMF (17,5%) and AC (11,9%). Trastuzumab was use in only 5,8% of the patients (Pu=6,8%, Pr=18,3% and PuPr 3% among all patients that received chemotherapy). In the adjuvant setting, Tamoxifen (TAM) was prescribed in 69,8% of the cases (Pu=87,6%, Pr=79,6% and PuPr 78,8%), AI in 8,2% (Pu=5,9%, Pr=9,3% and PuPr 13,8%), and sequential TAM/AI in 6,6% (Pu=6,1%, Pr=8,3% and PuPr 6,4%). About 17% of the patients had metastasis.

Conclusions: There are important differences between the public and private institutions in Brazil, the patients from the Pu institutions were five times more likely to be diagnosed in stage III or IV, they usually receive neoadjuvant treatment, and when surgery was done, most of them were treated with radical procedures. Besides the overexpression of Her-2 (30%) a minority of the patients received treatment with trastuzumab even for the Private centers (high cost for a developing country).

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-07-37.

Health concerns of consuming cockles (Cerastoderma edule L.) from a low contaminated coastal system

Commercial and recreational harvesting of shellfish within the coastal systems is usually very extensive. Since these ecosystems are frequently subjected to contamination, namely from agricultural, urban and industrial activities, and shellfish generally display a high capacity to bioaccumulate metals, populations may be at risk in terms of toxic metal exposure as a consequence of the harvesting and ingestion of near shore coastal marine organisms. Shellfish is regularly tested for concentrations of metals and other contaminants by legal authorities for commercial purposes, but although health officials use total metal as standards of food safety, only a part of the metal accumulated in shellfish is available to be assimilated and to cause toxic effect. In order to elucidate these issues an investigation on cockles inhabiting the Aveiro estuary was conducted. Element levels in sediments and wild Cerastoderma edule from sampling areas with different levels of contamination were measured; total element burden of cockles was related to accessible fraction for assimilation (TAM); element concentrations in wild C. edule were compared to EFSA (European Food Safe Authorities), USFDA (United States Food and Drug Administration) and FSANZ (Food Standards Australia and New Zealand) maximum levels (MLs); and the amount of cockle flesh needed to be consumed to exceed provisional tolerable weekly intake (PTWI) was determined. The present work showed that although sediment metal and metalloid contamination in Aveiro estuary is low the concentration of elements in C. edule does not reflect the contamination of the sediment. Aluminium (Al) and mercury (Hg) were the less and nickel (Ni), lead (Pb), zinc (Zn) and cadmium (Cd) were the most bioaccumulated metals by cockles. Comparison of MLs from international organisations with the concentration of elements in C. edule showed that arsenic (As) and Pb exceeded standard levels. The ingestion of less than 1 kg for As and 1.5 kg for Pb of cockles would result in exceeding the PTWI threshold (0.015 and 0.025 mg kg⁻¹ week⁻¹ respectively) in any of the areas considered in the study. Cd and Al also appear to be limiting elements for human consumption. Indeed, consumption of more than 3.1 kg and 2.1 kg of whole cockle soft part from one of the study areas during a single week would lead to exceedance of the recommended PTWI value for Cd (0.007 mg kg⁻¹ week⁻¹) and Al (7 mg kg⁻¹ week⁻¹) respectively. The health concerns to humans from cockle consumption from Aveiro estuary are discussed.

On the role of subtype selective adenosine receptor agonists during proliferation and osteogenic differentiation of human primary bone marrow stromal cells

Purines are important modulators of bone cell biology. ATP is metabolized into adenosine by human primary osteoblast cells (HPOC); due to very low activity of adenosine deaminase, the nucleoside is the end product of the ecto-nucleotidase cascade. We, therefore, investigated the expression and function of adenosine receptor subtypes (A(1) , A(2A) , A(2B) , and A(3) ) during proliferation and osteogenic differentiation of HPOC. Adenosine A(1) (CPA), A(2A) (CGS21680C), A(2B) (NECA), and A(3) (2-Cl-IB-MECA) receptor agonists concentration-dependently increased HPOC proliferation. Agonist-induced HPOC proliferation was prevented by their selective antagonists, DPCPX, SCH442416, PSB603, and MRS1191. CPA and NECA facilitated osteogenic differentiation measured by increases in alkaline phosphatase (ALP) activity. This contrasts with the effect of CGS21680C which delayed HPOC differentiation; 2-Cl-IB-MECA was devoid of effect. Blockade of the A(2B) receptor with PSB603 prevented osteogenic differentiation by NECA. In the presence of the A(1) antagonist, DPCPX, CPA reduced ALP activity at 21 and 28 days in culture. At the same time points, blockade of A(2A) receptors with SCH442416 transformed the inhibitory effect of CGS21680C into facilitation. Inhibition of adenosine uptake with dipyridamole caused a net increase in osteogenic differentiation. The presence of all subtypes of adenosine receptors on HPOC was confirmed by immunocytochemistry. Data show that adenosine is an important regulator of osteogenic cell differentiation through the activation of subtype-specific receptors. The most abundant A(2B) receptor seems to have a consistent role in cell differentiation, which may be balanced through the relative strengths of A(1) or A(2A) receptors determining whether osteoblasts are driven into proliferation or differentiation.

Coastal sediments under the influence of multiple organic enrichment sources: An evaluation using carbon and nitrogen stable isotopes

Sediment descriptors (grain size, total volatile solids, redox potential) and stable carbon and nitrogen isotopes were used to trace the origin of organic matter in a coastal area under multiple organic enrichment sources (urban outfall and a major estuary). The sediments fines content and total volatile solids were similar to outfall pre-operation period (1994), but the incorporation of terrestrial organic matter within the sediments located closer to the outfall was diagnosed by depleted (13)C values (-24.2+/-0.38 per thousand) and (15)N values (2.4+/-0.93 per thousand). Data also indicated depleted nitrogen signature at larger distances from the outfall than the carbon signature, due to confounding sediment grain size properties. Analysis in the bivalve Abra alba gave the same results for both isotopes and thus allowed a coherent interpretation of the spatial extent of the organic enrichment, highlighting the importance of bringing a biological element into the environmental assessment.

Computational fluid dynamics analysis of nasal flow

OBJECTIVES

Standard methods to examine nasal flow are experimental and do not yield locally detailed results. Using the Lattice-Boltzmann method (LBM), we computed nasal air flow and investigated the relationship between nasal obstruction and anatomical conditions. Because of its mathematical structure, the LBM can be immediately applied to various nasal cavities that are characterized by an extremely intricate geometry. In the present study, the higher efficiency of the LBM allowed for high resolution and detailed analysis of the flow structures in the nasal cavity.

METHODOLOGY

Based on a previously validated simulation of nasal airflow in an artificial model, we acquired the nasal geometry of an individual by computed tomography and applied the LBM to numerically solve Navier-Stokes equations and thereby determine nasal flow.

RESULTS

In contrast to frequently used standard finite-volume methods, our method facilitated grid generation and computational parallelisation. The grid modelling of the nasal cavity comprised 4.9 million nodes and the computational time on a high-performance computing cluster was less than 12 hours. The velocity and pressure of the calculated airflow was visualized in every tiny recess of the nasal cavity and areas of interest could be easily identified.

CONCLUSION

Computer-assisted visualization of patients' 3D nasal flow structures may be useful for diagnosis, and for planning surgical interventions. Although numerical analysis is far from real-time, and the generation of geometric models still requires a large amount of manual interaction, our simulation approach will be useful for nasal flow research.

Estuarine sediment acute toxicity testing with the European amphipod Corophium multisetosum Stock, 1952

This study assessed the use of the European amphipod Corophium multisetosum Stock [Stock, J.H., 1952. Some notes on the taxonomy, the distribution and the ecology of four species of the genus Corophium (Crustacea, Malacostraca). Beaufortia 21, 1-10] in estuarine sediment acute toxicity testing. The sensitivity of adults to the reference toxicant CdCl(2) was determined in water-only 96 h exposures in salinity 2. LC(50) values ranged from 0.33mgCd(2+)L(-1) at 22 degrees C to 0.57mgCd(2+)L(-1) at 15 degrees C. Adult survival was studied in control sediment with water salinity from 0 to 36 and with fine particles content (<63 microm) from 2% to 97% of total sediment, dry weight. Experiments were conducted at 15, 18 and 22 degrees C and the results indicate that the species can be used under the full salinity range although higher mortality was observed at the lower salinity in the higher water temperature, and at the higher salinity in the lower water temperature. The species also tolerated the studied range of sediment fines content and showed the highest sensitivity at intermediate values of fines, especially at the higher temperature, thus advising that tests which have to accommodate sediments with a wide range in fines content should preferably be conducted at 15 degrees C rather than at 22 degrees C. The response in natural sediments was studied in samples collected yearly from 1997 to 2006, at a site located off the Tagus Estuary, western Portugal. A major flood event in winter 2000-2001 induced detectable alterations in sediment baseline descriptors (grain-size, redox potential and total volatile solids), organic contaminants (PAHs, PCBs, DDT metabolites and gamma-HCH) and the macrofauna benthic community. Mortality of the amphipod diminished significantly from the before to the after flood period, in close agreement with diminishing sediment contamination and increasing benthic fauna diversity, in the same time period. C. multisetosum is suitable to conduct acute sediment toxicity tests and presents good potential for the development of a full life-cycle sediment test, due to its amenability to laboratory culture and high survival in the control sediment.

Penile Carcinoma: The Role of Koilocytosis in Groin Metastasis and the Association With Disease Specific Survival

PURPOSE

We evaluated the influence of koilocytosis, and other clinical and pathological variables in the risk of groin metastasis and death in penile cancer patients.

MATERIALS AND METHODS

From January 1994 to January 2004, 172 patients with squamous cell carcinoma of the penis were treated at a single cancer center. Of these patients 144 were retrospectively studied to analyze prognostic factors and establish the role of koilocytosis in penile cancer. Univariate and multivariate analyses were performed, and Kaplan-Meier survival curves were generated.

RESULTS

A total of 102 patients (71%) underwent groin dissection, of whom 84 (58.3%) had inguinal metastasis. Koilocytosis was present in 91 patients (63.1%) and it was associated with low and moderate primary tumor grade on univariate analysis (p = 0.0005). Although koilocytosis statistically correlated with Jackson stage (p = 0.017) and tumor grade (p = 0.002), it had no impact on disease specific survival (p = 0.912). Metastatic inguinal disease correlated with patient age, Jackson and disease specific survival. Only Jackson stage and inguinal relapse after groin dissection influenced overall survival on multivariate analysis (each p = 0.001).

CONCLUSIONS

According to all studied variables only patient age and Jackson stage correlated with an increased risk of groin disease. Koilocytosis was rarely found in high grade penile tumors and it did not correlate with a high risk of metastatic groin disease or death.

Validation of soft bottom benthic habitats identified by single-beam acoustics

Acoustic diversity charts were produced for a Portuguese soft bottom mid-shelf area, depth from 30 to 90 m, using a single-beam echo sounder coupled to the acoustic systems QTC VIEW Series IV and V. A similar acoustic pattern was identified by both systems, which, after ground-truth interpretation based in available sediment and biological data, established a preliminary spatial distribution model of the benthic habitats in this coastal area. However, some of the acoustic areas were interpreted using one or very few sediment and benthic samples. A specific validation survey was conducted a posteriori, in which the positioning of the sediment and benthic community sampling sites was based on the acoustic diversity previously identified. The results clearly confirm the benthic habitats distribution model suggested by the acoustic method, indicating a high potential for the use of such approach in the identification and mapping of large-scale soft bottom coastal shelf habitat diversity.

Reduced activity and protein expression of NOS in R6/2 HD transgenic mice: effects of L-NAME on symptom progression

Previous work found that dietary l-arginine alters symptom progression in mice transgenic for Huntington's disease (HD), and that cerebral blood flow (CBF) is abnormal in early stage HD patients. Both of these findings potentially implicate nitric oxide (NO) and its converting enzyme, nitric oxide synthase (NOS), in HD. The current experiment found that both NOS enzymatic activity and neuronal NOS (nNOS) protein expression were reduced (P<0.05) in R6/2 HD transgenic mice compared to non-HD controls (CON). Conversely, inducible NOS (iNOS) protein expression was not significantly different between groups. The changes in nNOS were accompanied by changes in protein expression of calmodulin kinase II (CaMKII) (P<0.05) and calmodulin kinase IV (CaMKIV) (P<0.05). Protein expression of 3-nitrotyrosine (3-NT), a marker for the neurotoxin peroxynitrite, was slightly increased in non-drug treated HD and was accompanied by increased immunostaining of 3-NT in cells adhering to the vasculature and choroid plexus. Mice that received the broad-spectrum NOS inhibitor N(g)-nitro-L-arginine methyl ester hydrochloride (L-NAME) via their drinking water had reduced NOS enzyme activity. NOS activity varied as a function of L-NAME dose, was virtually eliminated in the 500-mg/l groups, and correlated (P<0.05) with the behavioral scores as revealed by regression and correlation analyses. High dose L-NAME (500 mg/l) accelerated symptom onset in HD transgenics. These results support the hypothesis that nNOS activity and NO production are abnormal in HD, this in the setting of a more global dysregulation of calcium protein expression. Taken collectively with earlier data from our laboratory demonstrating abnormal CBF findings in early-stage HD patients, these results suggest that abnormalities in NOS function may significantly contribute to the neurodegeneration found in HD.

Water distribution and permeability of zebrafish embryos, Brachydanio rerio

Teleost embryos have not been successfully cryopreserved. To formulate successful cryopreservation protocols, the distribution and cellular permeability to water must be understood. In this paper, the zebrafish (Brachydanio rerio) was used as a model for basic studies of the distribution to permeability to water. These embryos are a complex multi-compartmental system composed of two membrane-limited compartments, a large yolk (surrounded by the yolk syncytial layer) and differentiating blastoderm cells (each surrounded by a plasma membrane). Due to the complexity of this system, a variety of techniques, including magnetic resonance microscopy and electron spin resonance, was used to measure the water in these compartments. Cellular water was distributed unequally in each compartment. At the 6-somite stage, the percent water (V/V) was distributed as follows: total in embryo = 74%, total in yolk = 42%, and total in blastoderm = 82%. A one-compartment model was used to analyze kinetic, osmotic shrinkage data and determine a phenomenological water permeability parameter, Lp, assuming intracellular isosmotic compartments of either 40 or 300 mosm. This analysis revealed that the membrane permeability changed (P < 0.05) during development. During the 75% epiboly to 3-somite stage, the mean membrane permeability remained constant (Lp = 0.022 +/- 0.002 micron x min-1atm-1 [mean +/- S.E.M.] assuming isosmotic is 40 mosm or Lp = 0.049 +/- 0.008 micron x min-1atm-1 assuming isosmotic is 300 mosm). However, at the 6-somite stage, Lp increased twofold (Lp = 0.040 +/- 0.004 micron x min-1atm-1 assuming isosmotic is 40 mosm or Lp = 0.100 +/- 0.017 micron x min-1atm-1 assuming isosmotic is 300 mosm). Therefore, the low permeability of the zebrafish embryo coupled with its large size (and consequent low area to volume ratio) led to a very slow osmotic response that should be considered before formulating cryopreservation protocols.