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.

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.

Trematode communities in cockles (Cerastoderma edule) of the Ria de Aveiro (Portugal): influence of inorganic contamination

This work aims to assess the trematode parasites infecting the edible cockle Cerastoderma edule, collected in the Ria de Aveiro lagoon, one of the most relevant biodiversity hotspots of the Western Iberia, and evaluate the relationship between the observed patterns and environmental descriptors. A total of 11 of the 16 trematode species known to infect C. edule were identified, including Himasthla continua and Psilostomum brevicolle as new occurrences in this lagoon. Parvatrema minutum was the most abundant and dominant species. Species richness and prevalence were high. The relationship between trematode species abundance, intensity and prevalence, and also environmental variables, showed that most parasites preferred muddy sand areas with euhaline conditions in opposition to areas with contamination and/or distant from the lagoon entrance. This study highlighted the good ecological status of the ecosystem and the transitional biogeographic characteristics of the western Portuguese coast where northern and subtropical faunas can coexist.

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.

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.

Early drain removal following modified radical mastectomy: a randomized trial

The dilemma of increasing costs of medical care and shrinking health budgets has stimulated attempts to implement stricter control on expenditure without affecting the quality of care. This study shows that in patients with operable breast cancer, a policy of early discharge after a mastectomy did not have deleterious effects on wound healing and was well accepted by patients. In a randomized trial, drains were removed after either 3 or 6 days postmastectomy, and in both groups of patients there was no difference between the mean volumes of seromas aspirated or the number of aspirations and return visits to the hospital. This suggests that a policy of early discharge is safe, acceptable, economical, and may improve bed utilization.

Integration of United States emergency medicine concepts into emergency services in the New Independent States

At this writing, a collaborative partnership has been in place for 30 months between the Boston University Medical Center, the University of Massachusetts Medical Center, the Armenian Ministry of Health, and the Emergency Hospital of Yerevan, Armenia, to improve emergency and trauma care in that city. Fifty-five individuals have traveled to and from the Emergency Hospital, the partner hospital. The collaboration has led to the creation of the Emergency Medical Services Institute (EMSI) at Emergency Hospital, an 800-bed facility that serves as a trauma center and as base for the Yerevan ambulance system. A curriculum (text and slides) has been developed and translated into Armenian and Russian. To date, the Armenian EMSI has trained nearly 300 emergency medical personnel: physicians, nurses, drivers, and first responders. The Armenian EMSI faculty have received training in directing instruction of emergency care providers. Plans are in place to begin training in Armenian cities outside of Yerevan and in neighboring republics. An emergency medicine residency program received ministry approval and was begun with six resident physicians in January 1995. To date, 45 nurses have graduated from a 400-hour training program. This partnership program chose an education initiative as the vehicle for interaction between the United States and the formerly Soviet-directed Armenian health care system. Officials of the partner hospital requested assistance in upgrading the skills of its abundant emergency care workforce, citing cardiovascular disease, trauma, and accidents as leading causes of death and disability in Armenia.(ABSTRACT TRUNCATED AT 250 WORDS)

Caffeine as a contaminant of concern: A review on concentrations and impacts in marine coastal systems

Caffeine has been identified as emerging contaminant of concern due to its widespread occurrence in the aquatic environment and potential to be biologically active. Recently, these concerns have been translated in an increasing research on its occurrence and effects on biota. However, there is still a limited knowledge on seawater matrices and the implications of caffeine presence in coastal and marine ecosystems are not fully known. The present review aims to fill these knowledge gaps, analysing the existing literature regarding the occurrence, effects and potential risks of caffeine residues to coastal ecosystems, contributing to the risk assessment of this psychoactive drug in the aquatic environment. The analysed literature reported caffeine concentrations in the coastal ecosystems, raising high concerns about the potential adverse impacts on the ecological safety and human health. Caffeine has been found in tissues from coastal and marine biota including microalgae, coral reefs, bivalves and fish due to bioaccumulation after chronic, long-term exposures in a contaminated environment. Additionally, caffeine residues had been demonstrated to have adverse impacts on aquatic organisms, at environmentally realistic concentrations, inducing oxidative stress and lipid peroxidation, neurotoxicity, changing energy reserves and metabolic activity, affecting reproduction and development and, in some cases, causing mortality. Considering the increasing adverse impacts of caffeine pollution in the coastal environment, this review highlights the urgent need to minimize the increasing load of caffeine to the aquatic ecosystems; being imperative the implementation of scientific programs and projects to classify effectively the caffeine as a high-priority environmentally hazardous emerging pollutant.

Peripheral osteoma of the mandibular condyle

Osteomas are benign bone neoplasms, classified as either peripheral or central. The peripheral variant is rare, with only six cases reported involving the mandibular condyle, that are not related to Gardner syndrome. The seventh case of peripheral osteoma involving the mandibular condyle is reported in this paper.

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.

Diagnosis of breast cancer in young women

While the prognosis of younger women with breast cancer is controversial, there have been several significant reports indicating a more unfavourable outcome of the disease in this age group. A review has been conducted of the problems encountered in the diagnosis of breast cancer in younger women. The records of 227 consecutive patients aged 30-40 years who underwent breast biopsy were retrospectively analysed, and data studied in relation to the proportion of malignant to benign biopsies, the clinical and pathological features of the malignant cases, and the method of diagnosis. A total of 235 biopsies was performed in 227 patients, of which 199 were benign (85%) and 36 were malignant (15%), giving a malignant to benign biopsy ratio of 1:5.5. Thirty-six cancers were diagnosed in 35 patients. Among these young women with breast cancer, the average duration of symptoms was 26 weeks, the mean clinical cancer diameter was 3.3 cm and only a small proportion (28%) of women had early (Stage I) disease. There were 4 women with breast cancer (11%), in whom the diagnosis of malignancy was unsuspected preoperatively. Mammography in these younger women appears to have a more limited role, with a sensitivity of only 76%. These findings indicate that the diagnosis of breast cancer in younger women is often more difficult than in older age groups and that the presentation and detection of such cancers is often delayed. Younger women need to be educated in relation to seeking early medical review of breast lumps and clinicians need to be aware of the limitations of mammography in such cases.

Sending out an SOS - the bacterial DNA damage response

The term “SOS response” was first coined by Radman in 1974, in an intellectual effort to put together the data suggestive of a concerted gene expression program in cells undergoing DNA damage. A large amount of information about this cellular response has been collected over the following decades. In this review, we will focus on a few of the relevant aspects about the SOS response: its mechanism of control and the stressors which activate it, the diversity of regulated genes in different species, its role in mutagenesis and evolution including the development of antimicrobial resistance, and its relationship with mobile genetic elements.

Ficopomatus enigmaticus larval development assay: An application for toxicity assessment of marine sediments

Ficopomatus enigmaticus is a serpulid polychaete, reef-forming, dioecious gamete spawner throughout different seasons and in different salinity conditions. Due to these characteristics, its candidacy as a model organism to monitor both marine and brackish matrices was assessed. Marine sediments collected in a polluted area near the port of Ancona (Italy) were used as case study. Besides the chemical characterization of sediments, the larval development of F. enigmaticus was adopted as an assay for ecotoxicological assessment of sediments in addition to a regulatory bioassay battery with different organisms and endpoints. The quality of sediments was classified according to the Italian Ministerial Decree for sediment management (Ministerial Decree 173, 2016) by using the SEDI-QUAL-SOFT® (ver. 109.0) software developed by the Italian Environmental Protection Agency (ISPRA). The F. enigmaticus larval development assay showed a quite similar sensitivity to C. gigas larval development assays, indicating its potential use in a regulatory battery of bioassays.

Brain tumours in south Brazil: a retrospective study of 438 cases

All brain tumours diagnosed since 1967 in a University Hospital in the Southern region of Brazil were reviewed and clinical information concerning age, sex, symptoms and evolution were analysed. 88.1% of tumours were primary neoplasms and the rest secondary deposits. There was a male predominance and the second and fifth decades of life were the most affected. The main presenting symptoms were headache, vomiting, hemiparesis, loss of vision and epilepsy. The commonest tumour was of astrocytic origin (36.3%) amongst which the malignant ones, including glioblastoma multiforme, predominated. These tumours were frequent in the cerebral hemispheres (31.3%), particularly in the frontal lobes. The time of evolution from the beginning of the clinical manifestations until the first hospital admission was also studied. The authors discuss the clinical and pathological observations in relation to other large series analysed in the literature.

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.

B-esterases characterisation in the digestive tract of the common octopus and the European cuttlefish and their in vitro responses to contaminants of environmental concern

Cephalopods are a group of marine invertebrates that have received little attention as sentinel species in comparison to other molluscs, such as bivalves. Consequently, their physiological and biochemical xenobiotic metabolism responses are poorly understood. Here we undertake a comparative analysis of the enzymatic activities involved in detoxification reactions and neural transmission in the digestive tract of two commercial cephalopods: the Common octopus, Octopus vulgaris, and the European cuttlefish, Sepia officinalis. For methodological purposes, several common B-esterases (five carboxylesterase (CE) substrates and three cholinesterase (ChE) determinations) were assayed as a proxy of metabolic and neuronal activities, respectively. Four components of the digestive tract in each species were considered: salivary glands, the stomach, the digestive gland and the caecum. The in vitro responses of digestive gland homogenates to model chemicals and contaminants of environmental concern were contrasted between both cephalopod species. The baseline biochemical activities in the four digestive tract components were also determined. Moreover, in order to validate the protocol, purified proteins, recombinant human CE (CE1 and CE2) and purified eel acetylcholinesterase (AChE) were included in the analysis. Overall, carboxylesterase activities were higher in octopus than in cuttlefish, with the activity quantified in the digestive tract components in the following order: digestive gland ≈ caecum > stomach ≈ salivary glands, with higher hydrolysis rates reached with naphthyl-derived substrates. In contrast, cuttlefish hydrolysis rates with ChE substrates were higher than in octopus. This trend was also reflected in a higher sensitivity to CE inhibitors in octopus and to AChE inhibitors in cuttlefish. Given the detoxification character of CEs and its protective role preventing AChE inhibition, octopus could be regarded as more efficiently protected than cuttlefish from neurotoxic exposures. A full characterisation of B-esterases in the digestive tract of the two common cephalopods is also provided.

Allograft nephrectomy: a single-institution, 10-year experience

INTRODUCTION

Allograft nephrectomy (AN) is associated with a high number of surgical complications. Some authors advocate that early nephrectomy (<1 year) is associated with fewer complications. Intracapsular (ICAN) and extracapsular AN (ECAN) might have a different impact on allosensitization and surgical outcomes. Our goal was to compare surgical outcomes between early and late AN in our institution and to compare ICAN and ECAN in terms of surgical outcomes and panel reactive antibodies (PRA) variation.

MATERIALS AND METHODS

Between January 2000 and October 2012, we performed 104 AN at our institution (32 early and 72 late). Comparisons between early and late AN, and, within the latter, between the 2 different techniques were sought. Statistical analysis was performed for sample description, group comparison and %PRA variation.

RESULTS

Among the 104 patients with a mean age of 47.9 ± 14.2 years, 54 were men. Age, gender, body mass index, and number of previous transplants were similar between early and late AN and between ICAN and ECAN patients. Late AN was associated with less blood loss (293.4 ± 229.0 vs 414.3 ± 349.5 mL; P = .03), shorter hospital stay (12.8 ± 14.5 vs 26.8 ± 26.5; P < .05), and fewer complications (22.2% vs 59.3%; P < .05). The chance of being relisted for transplantation was similar (50.0% in early vs 59.7% in late AN; P = .7). When comparing ICAN and ECAN, there was no difference in surgical outcomes. The %PRA variation between the 2 techniques was comparable (-1.2 ± 10.6 ICAN vs -0.5 ± 15.9 ECAN; P = .8), as was the chance of being relisted for transplantation (60.5% ICAN vs 58.6% ECAN; P = .8).

CONCLUSIONS

Early AN was associated with a greater number of surgical complications. Nevertheless, the number of AN patients returning to the active waiting list was similar between early and late AN groups. ICAN and ECAN had similar surgical and postoperative outcomes, although a bias may be present because some conversions from ECAN to ICAN occurred owing to technical issues. As in other studies, ICAN did not seem to affect allosensitization or jeopardize the chance of being relisted for transplant when compared with ECAN.

Will extreme weather events influence the toxic impacts of caffeine in coastal systems? Comparison between two widely used bioindicator species

In the recent years, marine heatwaves (MHWs) have caused devastating impacts on marine life. The understanding of the combined effects of these extreme events and anthropogenic pollution is a vital challenge. In particular, the combined effect of MHWs on the toxicity of pharmaceuticals to aquatic life remains unclear. To contribute to these issues, the main goal of the present investigation was to evaluate how MHWs may increase caffeine (CAF) toxicity on the clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis. Bioaccumulation levels and changes on oxidative stress, metabolic capacity and neurotoxic status related biomarkers were investigated. The obtained results revealed the absence of CAF accumulation in both species. However, the used contaminant generated in both bivalve species alteration on neurotransmission, detoxification mechanisms induction as well as cellular damage. The increase of antioxidant defence mechanisms was complemented by an increase of metabolic activity and decrease of energy reserves. The obtained results seemed magnified under a simulated MHWs, suggesting to a climate-induced toxicant sensitivities' response. On this perspective, understanding of how toxicological mechanisms interact with climate-induced stressors will provide a solid platform to improve effect assessments for both humans and wildlife.

Evaluation of 2 intravenous thrombolytic agents (anisoylated plasminogen streptokinase activator complex versus streptokinase) in patients with acute myocardial infarction

Ten patients with symptoms of acute myocardial infarction of less than 6 hours duration were randomised to receive either anisoylated plasminogen streptokinase activator complex [APSAC] (30U) or streptokinase (1,500,000U) intravenously. The aims of the study were to compare the angiographic patency of the infarct-related coronary arteries and to monitor drug safety and tolerance for up to 24 hours. The left anterior descending artery was occluded in 3, the left circumflex in 3 and right coronary artery in 4 patients. Time between onset of pain and treatment ranged from 150 to 330 minutes. At 90 minutes, 8 patients, 3 of 5 (60%) of the APSAC group and all of the streptokinase group, had patent arteries. No significant differences were found in measurements of coagulation. There were no haemorrhagic complications. One patient of the APSAC group had reinfarction 6 hours after treatment and died in cardiogenic shock. APSAC seems safe and is easier to use than streptokinase, and both agents result in patency in the majority of patients, although too few patients were included to allow a valid comparison. However, thrombolysis should be considered only a temporary solution in acute myocardial infarction, associated mainly with 3-vessel disease.

Effects of copper on larvae of the marbled crab Pachygrapsus marmoratus (Decapoda, Grapsidae): Toxicity test and biochemical marker responses

The importance of trace elements in ecotoxicological investigations is a well-known issue when monitoring polluted areas such as commercial harbors. Copper represents one of the most common metal contaminants, often detected in these areas as it is widely employed in various fields and has many sources of inflow in the marine environment. Pachygrapsus marmoratus is a widespread intertidal crab species that has been extensively studied in ecology, ethology and population genetics. Ecotoxicological studies have also been performed, exclusively on the adult stage. In the present study we investigated the mortality and biochemical (oxidative stress and neurotoxicity) responses of P. marmoratus larvae exposure to environmental relevant concentration of copper. Results showed dose-dependent responses in terms of larval mortality, with a calculated LC₅₀ value of 0.5 mg/L of Cu²⁺. The LC₅₀ concentration was used as the starting point for subsequent biochemical response evaluation. Results also demonstrated dose-dependent activation of antioxidant systems assuming a compensatory antioxidant activity to prevent higher cellular damage when larvae were exposed to the highest concentrations of copper. Moreover, a significant enhancement of neurotransmitter activities was observed, assuming a possible direct interaction of copper with the enzymes or an increase of free copper ion aliquot into the cells.

Atlantic and Mediterranean populations of the widespread serpulid Ficopomatus enigmaticus: Developmental responses to carbon nanotubes

Ficopomatus enigmaticus was adopted as model species for ecotoxicological bioassay, with its larval development as endpoint. Two different populations of the same species, collected in areas far from each other (Mediterranean Sea and Atlantic Ocean), were exposed to multi-walled carbon nanotubes, a class of emerging pollutants with a constantly increasing relevance in the landscape of nanomaterials production. Moreover, a molecular analysis based on Cyt b amplification and sequencing, was carried out to confirm that both populations belong to the same species. The aim of the present work was to strengthen existing results about F. enigmaticus relevance in ecotoxicological bioassays, adding the variable of population effect. For both populations the concentration-response curve of effect at different toxicant concentrations was similar and, at certain concentrations, overlapping, confirming the ecological relevance of the assay. These results posed an interesting acceptance on the introduction of this species as model in ecotoxicological bioassay scenery, underlining the relevance of a widespread wild species to compare effects of chemicals and environmental samples over large distances using the same bioassay.

Medial Malleolar Fractures: An Anatomic Survey Determining the Ideal Screw Length

Background:

Medial malleolar fractures are frequent, and their treatment is familiar to the orthopedic surgeon. Lag screw fixation using partially threaded screws remains the standard treatment method for medial malleolar fractures. However, the literature lacks a defined method for selecting lag screw length, relying more so on the empiric choice of the surgeon.

Aim:

The aim of this study is to help define the ideal lag screw length for medial melleolar fracture fixation.

Materials and Methods:

One hundred and sixteen anatomic specimens were included in the study. A transverse cut was performed in the distal third of the tibia, roughly 1 and a half times the distal tibial plafond width from the ankle joint. A coronal cut was then performed using the center of the medial malleolus. Three observers measured the distance between the medial malleolus tip and beginning of the medullary canal in all anatomic specimens. Differences in measurements were statistically compared, level of (P ≤ 0.05). Interclass correlation coefficient (ICC) significance level was set at P < 0.05.

Results:

Measurement average was 55 mm between the medial malleolus tip and the medullary canal, with a standard deviation of 10 mm. High concordance (ICC: 0.819) was achieved among all pairs of observers (P < 0.01). The systematic difference among measurements was absent, and random distribution around general measurements was observed.

Conclusion:

The authors recommend a screw length of no more than 45 mm to optimize the location of the screw threads in the best cancellous bone in an effort to obtain the most compression.

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.

Ocean acidification impact on the uptake of trace elements by mussels and their biochemical effects

This study delves into the intricate interplay between ocean acidification (OA), metal bioaccumulation, and cellular responses using mussels (Mytilus galloprovincialis) as bioindicators. For this purpose, environmentally realistic concentrations of isotopically labelled metals (Cd, Cu, Ag, Ce) were added to investigate whether the OA increase would modify metal bioaccumulation and induce adverse effects at the cellular level. The study reveals that while certain elements like Cd and Ag might remain unaffected by OA, the bioavailability of Cu and Ce could potentially escalate, leading to amplified accumulation in marine organisms. The present findings highlight a significant rise in Ce concentrations within different mussel organs under elevated pCO2 conditions, accompanied by an increased isotopic fractionation of Ce (140/142Ce), suggesting a heightened potential for metal accumulation under OA. The results suggested that OA influenced metal accumulation in the gills of mussels. Conversely, metal accumulation in the digestive gland was unaffected by OA. The exposure to both trace metals and OA affects the biochemical responses of M. galloprovincialis, leading to increased metabolic capacity, changes in energy reserves, and alterations in oxidative stress markers, but the specific effects on other biomarkers (e.g., lipid peroxidation, some enzymatic responses or acetylcholinesterase activity) were not uniform, suggesting complex interactions between the stressors and the biochemical pathways in the mussels.

Pollution effects on biochemical pathways determined in the polychaete Hediste diversicolor collected in three Portuguese estuaries

Biomonitoring is an important tool for the assessment of the quality and functions of ecosystems, providing information about the pollutants present and the direct effects that they exert on organisms. Biomonitoring relies upon the quantification of variables that can be biochemical, genetic, morphological and physiological changes. Such variables are designated as biomarkers, and multiple biomarkers are usually determined simultaneously in order to have a more integrated analysis and information about sublethal early effects of contaminants. In this work, we quantified biomarkers, associated with oxidative stress (glutathione-S-transferases GSTs, and catalase CAT, activities; levels of peroxidative alterations, by the thiobarbituric acid reactive substances assay, TBARS) and neurotoxicity (acetylcholinesterase activity, AChE) in the polychaete Hediste diversicolor. Organisms were collected at three distinct estuaries, Ria de Aveiro (Laranjo and São Jacinto), Douro River (São Paio, Afurada, and Ribeira da Granja), both impacted by human activities, and Minho River (Seixas), which has been used as a reference site. Obtained data showed the occurrence of anti-oxidant responses, in most samples from contaminated sites, which was not followed however by the occurrence of oxidative damage in organisms from Ria de Aveiro. None of the analyzed organisms had significant impairment of cholinesterasic activity, suggesting the absence of a prior exposure to neurotoxic compounds. In fact, organisms collected at Ria de Aveiro had largely increased AChE activity, suggesting an uncommon paradoxical biological response that is further discussed.