Wound healing and cancer progression in Opisthorchis viverrini associated cholangiocarcinoma

Letter to the editor

Structural characterization and immunogenicity in wild-type and immune tolerant mice of degraded recombinant human interferon Alpha2b

Purpose: This study was conducted to study the influence of protein structure on the immunogenicity in wild-type and immune tolerant mice of well-characterized degradation products of recombinant human interferon alpha2b (rhIFNα2b). Methods: RhIFNα2b was degraded by metal-catalyzed oxidation (M), cross-linking with glutaraldehyde (G), oxidation with hydrogen peroxide (H), and incubation in a boiling water bath (B). The products were characterized with UV absorption, circular dichroism and fluorescence spectroscopy, gel permeation chromatography, reverse-phase high-pressure liquid chromatography, sodium dodecyl sulfate polyacrylamide gel electrophoresis, Western blotting, and mass spectrometry. The immunogenicity of the products was evaluated in wild-type mice and in transgenic mice immune tolerant for hIFNα2. Serum antibodies were detected by enzyme-linked immunosorbent assay or surface plasmon resonance. Results: M-rhIFNα2b contained covalently aggregated rhIFNα2b with three methionines partly oxidized to methionine sulfoxides. G-rhIFNα2b contained covalent aggregates and did not show changes in secondary structure. H-rhIFNα2b was only chemically changed with four partly oxidized methionines. B-rhIFNα2b was largely unfolded and heavily aggregated. Nontreated (N) rhIFNα2b was immunogenic in the wild-type mice but not in the transgenic mice, showing that the latter were immune tolerant for rhIFNα2b. The anti-rhIFNα2b antibody levels in the wild-type mice depended on the degradation product: M-rhIFNα2b > H-rhIFNα2b ∼ N-rhIFNα2b ≫ B-rhIFNα2b; G-rhIFNα2b did not induce anti-rhIFNα2b antibodies. In the transgenic mice, only M-rhIFNα2b could break the immune tolerance. Conclusions: RhIFNα2b immunogenicity is related to its structural integrity. Moreover, the immunogenicity of aggregated rhIFNα2b depends on the structure and orientation of the constituent protein molecules and/or on the aggregate size.

Re-evaluation of a reported increased micronucleus frequency in lymphocytes of workers occupationally exposed to formaldehyde

A replicate evaluation of increased micronucleus (MN) frequencies in peripheral lymphocytes of workers occupationally exposed to formaldehyde (FA) was undertaken to verify the observed effect and to determine scoring variability. May–Grünwald–Giemsa-stained slides were obtained from a previously performed cytokinesis-block micronucleus test (CBMNT) with 56 workers in anatomy and pathology laboratories and 85 controls. The first evaluation by one scorer (scorer 1) had led to a highly significant difference between workers and controls (3.96 vs 0.81 MN per 1000 cells). The slides were coded before re-evaluation and the code was broken after the complete re-evaluation of the study. A total of 1000 binucleated cells (BNC) were analysed per subject and the frequency of MN (in ‰) was determined. Slides were distributed equally and randomly between two scorers, so that the scorers had no knowledge of the exposure status. Scorer 2 (32 exposed, 36 controls) measured increased MN frequencies in exposed workers (9.88 vs 6.81). Statistical analysis with the two-sample Wilcoxon test indicated that this difference was not significant (p = 0.17). Scorer 3 (20 exposed, 46 controls) obtained a similar result, but slightly higher values for the comparison of exposed and controls (19.0 vs 12.89; p = 0.089). Combining the results of the two scorers (13.38 vs 10.22), a significant difference between exposed and controls (p = 0.028) was obtained when the stratified Wilcoxon test with the scorers as strata was applied. Interestingly, the re-evaluation of the slides led to clearly higher MN frequencies for exposed and controls compared with the first evaluation. Bland–Altman plots indicated that the agreement between the measurements of the different scorers was very poor, as shown by mean differences of 5.9 between scorer 1 and scorer 2 and 13.0 between scorer 1 and scorer 3. Calculation of the intra-class correlation coefficient (ICC) revealed that all scorer comparisons in this study were far from acceptable for the reliability of this assay. Possible implications for the use of the CBMNT in human biomonitoring studies are discussed.

Subunits of the chaperonin CCT are associated with Tetrahymena microtubule structures and are involved in cilia biogenesis

The cytosolic chaperonin CCT is a heterooligomeric complex of about 900 kDa that mediates the folding of cytoskeletal proteins. We observed by indirect immunofluorescence that the Tetrahymena TpCCTalpha, TpCCTdelta, TpCCTepsilon, and TpCCTeta-subunits colocalize with tubulin in cilia, basal bodies, oral apparatus, and contractile vacuole pores. TpCCT-subunits localization was affected during reciliation. These findings combined with atomic force microscopy measurements in reciliating cells indicate that these proteins play a role during cilia biogenesis related to microtubule nucleation, tubulin transport, and/or axoneme assembly. The TpCCT-subunits were also found to be associated with cortex and cytoplasmic microtubules suggesting that they can act as microtubule-associated proteins. The TpCCTdelta being the only subunit found associated with the macronuclear envelope indicates that it has functions outside of the 900 kDa complex. Tetrahymena cytoplasm contains granular/globular-structures of TpCCT-subunits in close association with microtubule arrays. Studies of reciliation and with cycloheximide suggest that these structures may be sites of translation and folding. Combined biochemical techniques revealed that reciliation affects the oligomeric state of TpCCT-subunits being tubulin preferentially associated with smaller CCT oligomeric species in early stages of reciliation. Collectively, these findings indicate that the oligomeric state of CCT-subunits reflects the translation capacity of the cell and microtubules integrity.

Early patterns of recovery from disturbance in intertidal algal assemblages: consistency across regions within a marine province

The importance of disturbance and the subsequent rate and pattern of recovery has been long recognised as an important driver of community structure. Community recovery is affected by processes operating at local and regional scales yet the examination of community level responses to a standardised disturbance at regional scales (i.e. among regions under different environmental conditions) has seldom been attempted. Here, we mechanically disturbed rocky intertidal lower shore algal dominated assemblages at three locations within each of three different regions within the Lusitanian biogeographical province (Azores, northern Portugal and the Canary Islands). All organisms were cleared from experimental plots and succession followed over a period of 12 months at which time we formally compared the assemblage structure to that of unmanipulated controls. Early patterns of recovery of disturbed communities varied among regions and was positively influenced by temperature, but not by regional species richness. Different components of the assemblage responded differently to disturbance. Regional differences in the relative abundance and identity of species had a key influence on the overall assemblage recovery. This study highlights how regional-scales differences in environmental conditions and species pool are important determinants of recovery of disturbed communities.

A SON Enhanced Algorithm for Observed Time Differences Based Geolocation in Real 3G Networks

Conferência - 16th International Symposium on Wireless Personal Multimedia Communications (WPMC)- Jun 24-27, 2013

Reading performance in children with visual function anomalies

Aims - To compare reading performance in children with and without visual function anomalies and identify the influence of abnormal visual function and other variables in reading ability. Methods - A cross-sectional study was carried in 110 children of school age (6-11 years) with Abnormal Visual Function (AVF) and 562 children with Normal Visual Function (NVF). An orthoptic assessment (visual acuity, ocular alignment, near point of convergence and accommodation, stereopsis and vergences) and autorefraction was carried out. Oral reading was analyzed (list of 34 words). Number of errors, accuracy (percentage of success) and reading speed (words per minute - wpm) were used as reading indicators. Sociodemographic information from parents (n=670) and teachers (n=34) was obtained. Results - Children with AVF had a higher number of errors (AVF=3.00 errors; NVF=1.00 errors; p<0.001), a lower accuracy (AVF=91.18%; NVF=97.06%; p<0.001) and reading speed (AVF=24.71 wpm; NVF=27.39 wpm; p=0.007). Reading speed in the 3rd school grade was not statistically different between the two groups (AVF=31.41 wpm; NVF=32.54 wpm; p=0.113). Children with uncorrected hyperopia (p=0.003) and astigmatism (p=0.019) had worst reading performance. Children in 2nd, 3rd, or 4th grades presented a lower risk of having reading impairment when compared with the 1st grade. Conclusion - Children with AVF had reading impairment in the first school grade. It seems that reading abilities have a wide variation and this disparity lessens in older children. The slow reading characteristics of the children with AVF are similar to dyslexic children, which suggest the need for an eye evaluation before classifying the children as dyslexic.

Optimizing the renewable generation mix in the Portuguese power system based on temporal and spatial diversity

Renewable energy sources (RES) have unique characteristics that grant them preference in energy and environmental policies. However, considering that the renewable resources are barely controllable and sometimes unpredictable, some challenges are faced when integrating high shares of renewable sources in power systems. In order to mitigate this problem, this paper presents a decision-making methodology regarding renewable investments. The model computes the optimal renewable generation mix from different available technologies (hydro, wind and photovoltaic) that integrates a given share of renewable sources, minimizing residual demand variability, therefore stabilizing the thermal power generation. The model also includes a spatial optimization of wind farms in order to identify the best distribution of wind capacity. This methodology is applied to the Portuguese power system.

Environmental microbiology for public health: capturing international developments in the field

Environmental microbiology is an evolving science. This is in part driven by the development of new analytical techniques that are becoming more varied and powerful. Before they are applied, emerging techniques need to be critically evaluated by scientists, technical professionals, practitioners and students.

Optimizing the renewable generation mix in the portuguese power system based on temporal and spatial diversity

Renewable energy sources (RES) have unique characteristics that grant them preference in energy and environmental policies. However, considering that the renewable resources are barely controllable and sometimes unpredictable, some challenges are faced when integrating high shares of renewable sources in power systems. In order to mitigate this problem, this paper presents a decision-making methodology regarding renewable investments. The model computes the optimal renewable generation mix from different available technologies (hydro, wind and photovoltaic) that integrates a given share of renewable sources, minimizing residual demand variability, therefore stabilizing the thermal power generation. The model also includes a spatial optimization of wind farms in order to identify the best distribution of wind capacity. This methodology is applied to the Portuguese power system.

Clinical and Bacteriological Survey of Diabetic Foot Infections in Lisbon

AIMS: An epidemiological survey of diabetic foot infections (DFIs) in Lisbon, stratifying the bacterial profile based on patient demographical data, diabetic foot characteristics (PEDIS classification), ulcer duration and antibiotic therapy. METHODS: A transversal observational multicenter study, with clinical data collection using a structured questionnaire and microbiological products (aspirates, biopsies or swabs collected using the Levine method) of clinically infected foot ulcers of patients with diabetes mellitus (DM). RESULTS: Forty-nine hospitalized and ambulatory patients were enrolled in this study, and 147 microbial isolates were cultured. Staphylococcus was the main genus identified, and methicillin-resistant Staphylococcus aureus (MRSA) was present in 24.5% of total cases. In the clinical samples collected from patients undergoing antibiotic therapy, 93% of the antibiotic regimens were considered inadequate based on the antibiotic susceptibility test results. The average duration of an ulcer with any isolated multi-drug resistant (MDR) organism was 29 days, and previous treatment with fluoroquinolones was statistically associated with multi-drug resistance. CONCLUSIONS: Staphylococcus aureus was the most common cause of DFIs in our area. Prevalence and precocity of MDR organisms, namely MRSA, were high and were probably related to previous indiscriminate antibiotic use. Clinicians should avoid fluoroquinolones and more frequently consider the use of empirical anti-MRSA therapy.

Ankle antagonist coactivation in the double-support phase of walking: Stroke vs. healthy subjects

Introduction: Lesions at ipsilateral systems related to postural control at ipsilesional side, may justify the lower performance of stroke subjects during walking. Purpose: To analyse bilateral ankle antagonist coactivation during double-support in stroke subjects. Methods: Sixteen (8 females; 8 males) subjects with a first isquemic stroke, and twenty two controls (12 females; 10 males) participated in this study. The double support phase was assessed through ground reaction forces and electromyography of ankle muscles was assessed in both limbs. Results: Ipsilesional limb presented statistical significant differences from control when assuming specific roles during double support, being the tibialis anterior and soleus pair the one in which this atypical behavior was more pronounced. Conclusion: The ipsilesional limb presents a dysfunctional behavior when a higher postural control activity was demanded.

The End-Organ Impairment in Liver Cirrhosis: Appointments for Critical Care

Liver cirrhosis (LC) can lead to a clinical state of liver failure, which can exacerbate through the course of the disease. New therapies aimed to control the diverse etiologies are now more effective, although the disease may result in advanced stages of liver failure, where liver transplantation (LT) remains the most effective treatment. The extended lifespan of these patients and the extended possibilities of liver support devices make their admission to an intensive care unit (ICU) more probable. In this paper the LC is approached from the point of view of the pathophysiological alterations present in LC patients previous to ICU admission, particularly cardiovascular, but also renal, coagulopathic, and encephalopathic. Infections and available liver detoxifications devices also deserve mentioning. We intend to contribute towards ICU physician readiness to the care for this particular type of patients, possibly in dedicated ICUs.

Perinatal Outcome and Change in Body Mass Index in Mothers of Dichorionic Twins: a Longitudinal Cohort Study

We used a prospective cohort to analyze the effect of change in BMI rather than change in weight, in mothers carrying dichorionic twins from a population that did not receive any dietary intervention. A total of 269 mothers (150 nulliparas and 119 multiparas) were evaluated. The average change (%) from the pre-gravid BMI was 7.2+/-6.1, 17.4+/-8.2, and 28.7+/-10.8, at 12-14, 22-25, and 30-34 weeks, respectively, without difference between nulliparas and multiparas. The comparison between maternities below or above the average change from the pregravid BMI failed to demonstrate an advantage (in terms of total twin birthweight and gestational age) of an above average change from the pregravid BMI, even when the lower versus upper quartiles were compared. Our observations reached different conclusions regarding the recommended universal dietary intervention in twin gestations. A cautious approach is advocated towards seemingly harmless excess weight gain, as normal weight women may turn overweight, or even obese, by the end of pregnancy, and be exposed to the untoward effects of obesity on future health and body image.

Gastric Outlet Obstruction in a Patient with Bouveret's Syndrome: a Case Report

BACKGROUND: Gallstone ileus accounts for 1% to 4% of cases of mechanical bowel obstruction, but may be responsible for up to 25% of cases in older age groups. In non-iatrogenic cases, gallstone migration occurs after formation of a biliary-enteric fistula. In fewer than 10% of patients with gallstone ileus, the impacted gallstones are located in the pylorus or duodenum, resulting in gastric outlet obstruction, known as Bouveret's syndrome. CASE PRESENTATION: We report an 86-year-old female who was admitted to hospital with a 10-day history of persistent vomiting and prostration. She was in hypovolemic shock at the time of arrival in the emergency department. Investigations revealed a gallstone in the duodenal bulb and a cholecystoduodenal fistula. She underwent surgical gastrolithotomy. Unfortunately, she died of aspiration pneumonia on the fourth postoperative day. CONCLUSION: This case shows the importance of considering Bouveret's syndrome in the differential diagnosis of gastric outlet obstruction, especially in the elderly, even in patients with no previous history of gallbladder disease.