Efficacy of levamisole, ivermectin and moxidectin against Capillaria spp. in European hedgehogs (Erinaceus europaeus)

This randomised study aimed to assess and compare the efficacy of treatment protocols containing levamisole, ivermectin, or moxidectin against Capillaria spp. in naturally infected European hedgehogs (Erinaceus europaeus) presented to a British wildlife rehabilitation centre. Faecal analysis, consisting of wet mount and flotation, was performed for 229 hedgehogs weighing ≥200g. Animals testing positive for Capillaria spp. (81%), excluding pregnant females, were randomly allocated a treatment protocol. Initially, hedgehogs (n = 50) received one of six 'pilot' protocols, whereas the remaining animals (n = 97) received one of three 'main' protocols. Faecal analysis was repeated on day 8 and day 12 after treatment initiation. Efficacy of each treatment was assessed based on Capillaria reduction rate (CRR), weight gain, presence of respiratory clinical signs, and outcome. Pilot protocols containing only moxidectin had a significantly lower CRR (≥28.1%) compared to those with levamisole or ivermectin (≥86.6%), whereas the main protocols containing levamisole had a significantly higher CRR (≥93.0%) compared to those containing only ivermectin (≥69.3%). Clinical parameters did not differ significantly between treatments, but animals with respiratory clinical signs at the end of the trial were significantly more likely to have lower CRR and test positive for Crenosoma striatum. C. striatum often appeared refractory to treatment, and managing these infections requires additional anthelmintic therapy. Based on the formulations and dosages trialled, moxidectin is not recommended for treating capillariosis in European hedgehogs, whereas levamisole given orally for two consecutive days at 25-35 mg/kg is suggested as the treatment of choice.

Resistance of Soybean Genotypes to Anticarsia gemmatalis (Lepidoptera: Erebidae): Antixenosis and Antibiosis Characterization

Injury by herbivores is a major biotic stress that limits soybean [Glycine max (L.) Merrill] crop production. Among the main soybean insect pests, Anticarsia gemmatalis Hübner is responsible for causing significant economic damage in soybean. The primary management strategy for this insect is chemical control and use of Bt transgenic soybean. Alternative strategies, such as host plant resistance, are considered an efficient and less-aggressive method, especially in association with other strategies as part of an integrated pest management (IPM) approach. In this study, we evaluated 30 soybean genotypes to verify antixenosis expression through oviposition, attractiveness, and food consumption tests. From this, we selected 13 promising genotypes to verify the possible presence of antibiosis. Our results suggest that antixenosis was found in genotypes 'TMG 133' RR, 'TMG 1179' RR, 'IAC 19', 'IAC 17', 'IAC 100', D75-10169, and IAC 78-2318. By influence on behavior and negative impact on larval viability, antixenosis and antibiosis were indicated for the genotypes IAC 74-2832, 'IAC 19', 'IAC 17', 'IAC 100', and PI 274454. 'TMG 7062' IPRO was found to provide antibiosis resistance by negatively affecting larval development and viability. Because of reduced food consumption by larvae, antixenosis was indicated for 'IAC 24'. These genotypes should be considered in soybean breeding programs focusing on soybean resistance to A. gemmatalis.

Gene expression and genetic control to cold tolerance during maize seed germination

BACKGROUND

The study of cold tolerance in maize seeds and seedlings through physiological quality assessments, as well as the genetic control associated with this trait, allows an early characterization of genotypes. Here we studied the genetic control for cold tolerance during the germination process in maize seeds and genes influenced by this stress.

RESULTS

Six maize lines were used, three classified as tolerant and three as susceptible to low germination temperature. A field was developed to produce the hybrid seeds, in a partial diallel scheme including the reciprocal crosses. For the expression analysis, seeds from two contrasting lines were used, as well as their hybrid combination and their reciprocal crosses, on dried and moistened seeds at 10 °C for 4 and 7 days. It was evaluated the catalase (CAT) and esterase (EST) enzymes, heat-resistant proteins and the genes Putative stearoyl-ACP desaturase (SAD), Ascorbate Peroxidase (APX), Superoxide Dismutase (SOD) and Mitogen Activated Protein Kinase (ZmMPK5). The estimated values ​​for heterosis, general and specific combining abilities and reciprocal maternal and non-maternal effects were carried out and it showed that there is heterosis for germination at low temperatures, also the non-additive genes were more important and there was a reciprocal effect.

CONCLUSIONS

There is a greater expression of the CAT and EST enzymes in moistened seeds at seven days and there is less expression of heat-resistant proteins and the SAD gene at seven days of moistening. Also, there are variations in the expression of the APX, SOD and ZmMPK5 genes in dried and moistened seeds, as well as among the genotypes studied.

Application and stability of cathodes with manganese dioxide nanoflowers supported on Vulcan by Fenton systems for the degradation of RB5 azo dye

This work describes the electrochemical degradation of Reactive Black 5 (RB5) by two methods: electrochemical and photo-assisted electrochemical degradation with and without a Fenton reagent. Two anodes were used, Pt and boron-doped diamond (BDD, 2500 ppm), and the cathode was 3% MnO₂ nanoflowers (NFMnO₂) on a carbon gas diffusion electrode (GDE). An electrochemical cell without a divider with a GDE with 3% w/w NFMnO₂/C supported on carbon Vulcan XC72 was used. The decolorization efficiency was monitored by UV-vis spectroscopy, and the degradation was monitored by Total Organic Carbon (TOC) analysis. For dissolution monitoring, aliquots (1 mL) were collected during the degradation. After 6 h of H₂O₂ electrogeneration, the manganese concentration in the RB5 solution was only 23.1 ± 1.2 μg L^-1. It was estimated that approximately 60 μg L^-1 (<0.2%) of manganese migrated from the GDE to the solution after 12 h of electrolysis, which indicated the good stability of the GDE. The photoelectro-Fenton-BDD (PEF-BDD) processes showed both the best color removal percentage (∼93%) and 91% of mineralization. The 3% NFMnO₂/C GDE is promising for RB5 degradation.

Characteristics of 1555 childhood-onset lupus in three groups based on distinct time intervals to disease diagnosis: a Brazilian multicenter study

Objective The objective of this study was to compare demographic data, clinical/laboratorial features and disease activity at diagnosis in three different groups with distinct time intervals between onset of signs/symptoms and disease diagnosis. Methods A multicenter study was performed in 1555 childhood-onset systemic lupus erythematosus (American College of Rheumatology criteria) patients from 27 pediatric rheumatology services. Patients were divided into three childhood-onset systemic lupus erythematosus groups: A: short time interval to diagnosis (<1 month); B: intermediate time interval (≥1 and <3 months); and C: long time interval (≥3 months). An investigator meeting was held to define the protocol. Demographic data, SLICC classification criteria and SLEDAI-2 K were evaluated. Results The number of patients in each group was: A = 60 (4%); B = 522 (33.5%); and C = 973 (62.5%). The median age at diagnosis (11.1 (4.2-17) vs. 12 (1.9-17.7) vs. 12.5 (3-18) years, P = 0.025) was significantly lower in group A compared with groups B and C. The median number of diagnostic criteria according to SLICC (7 (4-12) vs. 6 (4-13) vs. 6 (4-12), P < 0.0001) and SLEDAI-2 K (18 (6-57) vs. 16 (2-63) vs. 13 (1-49), P < 0.0001) were significantly higher in group A than the other two groups. The frequency of oral ulcers in the palate (25% vs. 15% vs. 11%, P = 0.003), pleuritis (25% vs. 24% vs. 14%, P < 0.0001), nephritis (52% vs. 47% vs. 40%, P = 0.009), neuropsychiatric manifestations (22% vs. 13% vs. 10%, P = 0.008), thrombocytopenia (32% vs. 18% vs. 19%, P = 0.037), leucopenia/lymphopenia (65% vs. 46% vs. 40%, P < 0.0001) and anti-dsDNA antibodies (79% vs. 66% vs. 61%, P = 0.01) were significantly higher in group A compared with the other groups. In contrast, group C had a less severe disease characterized by higher frequencies of synovitis (61% vs. 66% vs. 71%, P = 0.032) and lower frequencies of serositis (37% vs. 33% vs. 25%, P = 0.002), proteinuria >500 mg/day (48% vs. 45% vs. 36%, P = 0.002) and low complement levels (81% vs. 81% vs. 71%, P < 0.0001) compared with groups A or B. Conclusions Our large Brazilian multicenter study demonstrated that for most childhood-onset systemic lupus erythematosus patients, diagnosis is delayed probably due to mild disease onset. Conversely, the minority has a very short time interval to diagnosis and a presentation with a more severe and active multisystemic condition.

Mechanomyography signals in spastic muscle and the correlation with the modified Ashworth scale

The modified Ashworth scale (MAS) is the most widely used measurement technique to assess levels of spasticity. In MAS, the evaluator graduates spasticity considering his/her subjective analysis of the muscular endurance during passive stretching. Therefore, it is a subjective scale. Mechanomyography (MMG) allows registering the vibrations generated by muscle contraction and stretching events that propagate through the tissue until the surface of the skin. With this in mind, this study aimed to investigate possible correlations between MMG signal and muscle spasticity levels determined by MAS. We evaluated 34 limbs considered spastic by MAS, including upper and lower limbs of 22 individuals of both sexes. Simultaneously, the MMG signals of the spastic muscle group (agonists) were acquired. The features investigated involved, in the time domain, the median energy (MMGME) of the MMG Z-axis (perpendicular to the muscle fibers) and, in the frequency domain, the median frequency (MMG_mf). The Kruskal-Wallis test (p<;0.001) determined that there were significant differences between intergroup MAS spasticity levels for MMG_me. There was a high linear correlation between the MMG_me and MAS (R²=0.9557) and also a high correlation as indicated by Spearman test (ρ=0.9856; p<;0.001). In spectral analysis, the Kruskal-Wallis test (p = 0.0059) showed that MMG_mf did not present significant differences between MAS spasticity levels. There was moderate linear correlation between MAS and MMG_mf (R²=0.4883 and Spearman test [ρ = 0.4590; p <; 0.001]). Between the two investigated features, we conclude that the median energy is the most viable feature to evaluate spasticity due to strong correlations with the MAS.

Short communication: The effects of dry matter and length of storage on the composition and nutritive value of alfalfa silage

During the ensiling of feeds, various processes result in chemical changes that can affect their ultimate nutritive value at feed out. The primary objective of this study was to evaluate the effect of prolonged ensiling times on potential changes in in vitro digestibility of neutral detergent fiber (NDF-D) of alfalfa ensiled at about 33% [low dry matter (DM), LDM] or 45% (high DM, HDM) whole-plant DM. Alfalfa from the same field (direct chopped or wilted) was chopped with a conventional forage harvester set for a theoretical length of cut of 0.95 cm and ensiled in mini silos for 45, 180, 270, and 360 d. Fresh forages and silages were analyzed for nutrient content, fermentation end-products, and 30-h NDF-D. The pH of the fresh forages ranged from 6.1 to 6.2 and decreased to approximately 4.7 and 4.3 in HDM and LDM silages, respectively. Production of acids and alcohols were less in HDM compared with LDM as expected. Concentrations of soluble protein and NH3-N also increased with time of storage as expected but soluble protein was greater, whereas NH3-N was lower in HDM compared with LDM silage. The effect of length of storage and DM on hemicellulose and NDF concentrations were very small, whereas DM content at harvest tended to slightly increase the concentration of acid detergent fiber in HDM compared with LDM up to 270 d of storage. The NDF-D was greater in fresh forage compared with corresponding silages. However, time of storage between 45 and 360 d had no effect on the NDF-D of alfalfa silage, regardless of DM concentration at ensiling.

Robustness of optimal random searches in fragmented environments

The random search problem is a challenging and interdisciplinary topic of research in statistical physics. Realistic searches usually take place in nonuniform heterogeneous distributions of targets, e.g., patchy environments and fragmented habitats in ecological systems. Here we present a comprehensive numerical study of search efficiency in arbitrarily fragmented landscapes with unlimited visits to targets that can only be found within patches. We assume a random walker selecting uniformly distributed turning angles and step lengths from an inverse power-law tailed distribution with exponent μ. Our main finding is that for a large class of fragmented environments the optimal strategy corresponds approximately to the same value μ(opt)≈2. Moreover, this exponent is indistinguishable from the well-known exact optimal value μ(opt)=2 for the low-density limit of homogeneously distributed revisitable targets. Surprisingly, the best search strategies do not depend (or depend only weakly) on the specific details of the fragmentation. Finally, we discuss the mechanisms behind this observed robustness and comment on the relevance of our results to both the random search theory in general, as well as specifically to the foraging problem in the biological context.

Effects of a spoilage yeast from silage on in vitro ruminal fermentation

Feeding silages with high concentrations of yeasts from aerobic spoilage is often implicated as a cause of poor animal performance on dairies. Our objective was to determine if a commonly found spoilage yeast, isolated from silage, had the potential to alter in vitro ruminal fermentations. A single colony of Issatchenkia orientalis, isolated from high-moisture corn, was grown in selective medium. The yeast culture was purified and added to in vitro culture tubes containing a total mixed ration (43% concentrate, 43% corn silage, 11% alfalfa haylage, and 3% alfalfa hay on a dry matter basis), buffer, and ruminal fluid to achieve added theoretical final concentrations of 0 (CTR), 4.40 (low yeast; LY), 6.40 (medium yeast; MY), and 8.40 (high yeast; HY) log10 cfu of yeast/mL of in vitro fluid. Seven separate tubes were prepared for each treatment and each time point and incubated for 12 and 24h at 39 °C. At the end of the incubation period, samples were analyzed for pH, yeast number, neutral detergent fiber (NDF) digestibility, volatile fatty acids (VFA), and fatty acids (FA). We found that total viable yeast counts decreased for all treatments in in vitro incubations but were still relatively high (5.3 log10 cfu of yeasts/mL) for HY after 24h of incubation. Addition of HY resulted in a lower pH and higher concentration of total VFA in culture fluid compared with other treatments. Moreover, additions of MY and HY decreased in vitro NDF digestibility compared with CTR, and the effect was greatest for HY. Overall, the biohydrogenation of dietary unsaturated FA was not altered by addition of I. orientalis and decreased over time with an increase in the accumulation of saturated FA, especially palmitic and stearic acids. We conclude that addition of I. orientalis, especially at high levels, has the potential to reduce in vitro NDF digestion and alter other aspects of ruminal fermentations.

Optical conductivity of curved graphene

We compute the optical conductivity for an out-of-plane deformation in graphene using an approach based on solutions of the Dirac equation in curved space. Different examples of periodic deformations along one direction translates into an enhancement of the optical conductivity peaks in the region of the far- and mid-infrared frequencies for periodicities ∼100 nm. The width and position of the peaks can be changed by dialling the parameters of the deformation profiles. The enhancement of the optical conductivity is due to intraband transitions and the translational invariance breaking in the geometrically deformed background. Furthermore, we derive an analytical solution of the Dirac equation in a curved space for a general deformation along one spatial direction. For this class of geometries, it is shown that curvature induces an extra phase in the electron wave function, which can also be explored to produce interference devices of the Aharonov-Bohm type.

Unveiling a mechanism for species decline in fragmented habitats: fragmentation induced reduction in encounter rates

Several studies have reported that fragmentation (e.g. of anthropogenic origin) of habitats often leads to a decrease in the number of species in the region. An important mechanism causing this adverse ecological impact is the change in the encounter rates (i.e. the rates at which individuals meet other organisms of the same or different species). Yet, how fragmentation can change encounter rates is poorly understood. To gain insight into the problem, here we ask how landscape fragmentation affects encounter rates when all other relevant variables remain fixed. We present strong numerical evidence that fragmentation decreases search efficiencies thus encounter rates. What is surprising is that it falls even when the global average densities of interacting organisms are held constant. In other words, fragmentation per se can reduce encounter rates. As encounter rates are fundamental for biological interactions, it can explain part of the observed diminishing in animal biodiversity. Neglecting this effect may underestimate the negative outcomes of fragmentation. Partial deforestation and roads that cut through forests, for instance, might be responsible for far greater damage than thought. Preservation policies should take into account this previously overlooked scientific fact.

Short-term effects of silage volatile compounds on feed intake and digestion in beef cattle

Two experiments were conducted to evaluate whether fermentation end products in silage affect intake and digestion in beef cattle. Six rumen-cannulated Nellore steers were randomly assigned to a replicated 3 × 3 Latin square design with 14-d periods. Each period consisted of 9 d for adaptation and 5 d for sample collection. Steers were housed in a tie-stall barn and individually fed once daily at 0800 h. The dietary treatments in Exp. 1 were as follows: 60% corn silage plus 40% concentrate (CON), 60% corn silage with added ethanol (2.8% on a DM basis) and 40% concentrate (ET), and 60% corn silage with added lactic acid (5.4% on a DM basis) and 40% concentrate (LA). The DMI was similar (P = 0.41) across treatments (average 11.7 kg/d); however, the LA treatment increased the ruminal pH (P = 0.01) and decreased the acetate:propionate ratio (P < 0.01). Diet digestibility decreased by 2.2 to 2.5 percentage units when the DM content was determined by oven drying (at 105°C) rather than by toluene distillation. The treatments in Exp. 2 were as follows: 75% sugarcane silage with no volatile fraction (oven dried at 60°C and rehydrated) and 25% concentrate (75D), 75% sugarcane silage (original moisture content) and 25% concentrate (75W), and 40% sugarcane silage and 60% concentrate (40W). Approximately 21% of the DM content of sugarcane silage consisted of volatile compounds. The presence of these compounds did not alter the DMI (P = 0.36) but did increase both the acetate:propionate ratio (P < 0.01) and the fractional absorption rates of valerate (P < 0.01) and ethanol (P = 0.02) in the empty reticulorumen. The 40W diet led to a greater DMI (40W = 9.79 vs. 75W = 6.19 kg/d; P < 0.01), which altered most of the measured variables traditionally associated with high-concentrate diets. As in Exp. 1, diet digestibility decreased by 1.5 to 5.4 units when the DM content was determined by oven drying at 105°C rather than by toluene distillation. In this short-term study, volatile compounds did not inhibit the DMI or the digestion process of the animals. On the contrary, volatile compounds contributed to the energy content of the silage, composing up to 10% of the energy value as determined by digestibility. Due to the short experimental periods, the results from this study should be interpreted with caution.

Conditions under which a superdiffusive random-search strategy is necessary

Intuitively, lower target densities and lower detection capabilities should demand more sophisticated search strategies for a random search reasonable outcome. In contrast, when targets are easily found, a simple Brownian random walk strategy is enough. But where is the threshold between these two scenarios and when is optimization really necessary? We address this considering the interplay between two essential scales in random search, the average distance between neighbor targets l(0) and the detection capability r(v). In the limit cases the ratio β=r(v)/l(0) suffices to characterize the problem. For low (high) β a superdiffusive behavior is (is not) crucial for the process optimization. However, there is a crossover range, which is a nontrivial function of r(v) and l(0), separating the two regimes. We analyze this intermediate region, common in nature, and discuss the often overlooked important trade between resources availability and the searcher location power. Our results highlight contexts where efficient random search is a key factor for survival, such as in animal foraging.

A green strategy for desorption of trihalomethanes adsorbed by humin and reuse of the fixed bed column

The objective of the present work was to develop a thermal desorption method for the removal of trihalomethanes (THM) adsorbed by humin, followed by multiple recycling of the fixed bed column in order to avoid excessive consumption of materials and reduce operating costs. The results obtained for adsorption on a fixed bed column confirmed the effectiveness of humin as an adsorbent, extracting between 45.9% and 90.1% of the total THM (TTHM). In none of the tests was the column fully saturated after 10h. Experiments involving thermal desorption were used to evaluate the potential of the technique for column regeneration. The adsorptive capacity of the humin bed increased significantly (p<0.05) between the first and fifth desorption cycle, by 18.9%, 18.1%, 24.2%, 20.2% and 24.2% for CHBr(3), CHBr(2)Cl, CHBrCl(2), CHCl(3) and TTHM, respectively.

Dimensioning of OFDMA PON with non-preselected independent ONUs sources and wavelength-control

A simple and low cost method for wavelength control of economical random non-preselected independent ONU sources is shown to increase the number of users in an OFDMA-PON. The method is based on OLT monitoring and thermal tuning control; it has been validated through Monte-Carlo simulations and a probabilistic model. The minimum optical spectral gap between the ONUs wavelengths that guarantees a tolerable amount of optical beat interference has been determined through an experiment.

Occupational stress and coping resources in physiotherapists: a survey of physiotherapists in three general hospitals

OBJECTIVES

To identify occupational stressors and coping resources in a group of physiotherapists, and to analyse interactions between subjective levels of stress, efficacy in stress resolution and coping resources used by these professionals.

DESIGN

A sample of 55 physiotherapists working in three general hospitals in Portugal completed the Coping Resources Inventory for Stress, the Occupational Stressors Inventory and two subjective scales for stress and stress resolution.

MAIN RESULTS

Most physiotherapists perceived that they were moderately stressed (19/55, 35%) or stressed (20/55, 36%) due to work, and reported that their efficacy in stress resolution was moderate (25/54, 46%) or efficient (23/54, 42%). Issues related to lack of professional autonomy, lack of organisation in the hierarchical command chain, lack of professional and social recognition, disorganisation in task distribution and interpersonal conflicts with superiors were identified as the main sources of stress. The most frequently used coping resources were social support, stress monitoring, physical health and structuring. Perceived efficacy in stress resolution was inversely related to perceived level of occupational stress (r=-0.61, P<0.01). Significant correlations were found between several coping resources and the perceived level of stress and efficacy in stress resolution. Associations between problem solving, cognitive restructuring and stress monitoring and both low levels of perceived stress and high levels of perceived efficacy were particularly strong.

IMPLICATIONS FOR PRACTICE

The importance of identifying stressors and coping resources related to physiotherapists' occupational stress, and the need for the development of specific training programmes to cope with stress are supported.

An ergonomic approach to reorganize parking inspection agents' work productivity, health and safety in São Paulo, Brazil

OBJECTIVE

The Traffic Engineering Company of the City of São Paulo (Brazil) observed a decrease in productivity, and an increase in sick leave, accidents and psychological distress among their parking inspection agents. To document this situation, qualitative research was undertaken to obtain an in-depth comprehension of work activity.

PARTICIPANTS

Workers, managers and health and safety professionals contributed to the documentation of the problem and to the proposal of possible solutions.

METHODS

Ergonomic work analysis focusing on real work activity, as well as interviews with individual or groups of stakeholders, were conducted.

RESULTS

This research revealed that political-economic factors gradually contributed to: 1) an increasing work load; 2) growing fatigue throughout the day, increasing the workers' vulnerability to incidents and accidents and their tendency to react inappropriately to violence experienced on the street; and 3) excessive individual responsibility to manage dangerous situations.

CONCLUSIONS

Recommendations to ameliorate the situation are proposed. These suggestions are discussed in terms of feasibility given the impact of macro social factors upon micro work activity, and the associated potential expansion of the ergonomist's role.

Adsorption of trihalomethanes by humin: Batch and fixed bed column studies

The objective of the present work was to assess the performance of batch and fixed bed column systems, using humin in natura and immobilized on sodium silicate, respectively, for the adsorption of the principal trihalomethanes (THMs) found in water supply systems. Kinetically, adsorption of THMs by humin follows a pseudo-second order reaction, with more than 50% removal in the first 5min for all compounds studied, and equilibrium described by the Freundlich model reached in 240min. The THM adsorption results were significant at p<0.05 for both batch (74.6-83.2% removal) and column (99.7% removal in optimized tests) experiments, and were significantly (p<0.05) influenced by flow rate and bed height. The work demonstrates the potential of humin for removal of THMs.

Specificity and sensitivity of screening for anti-HLA antibodies in kidney allograft dysfunction

BACKGROUND

Prospective testing for posttransplant circulating anti-HLA antibodies seems to be a critical noninvasive tool, but confirmatory data are lacking.

MATERIALS AND METHODS

Over the last 3 years, peritubular capillary (PTC) C4d deposition was prospectively sought by an immunofluorescence technique applied to frozen tissue in biopsies obtained for allograft dysfunction. Screening for circulating anti-HLA class I/II alloantibodies (AlloAb) by the flow cytometric test was performed simultaneously.

RESULTS

We evaluated 132 sets of biopsies and simultaneous serum samples. PTC C4d deposition was demonstrated in 15.9% (21/132) of biopsies. Circulating anti-HLA I/II AlloAb were detected in 25% (33/132) of serum samples. Employing receiver-operator characteristic (ROC) curves for all C4d-positive biopsies, screening for AlloAb showed a global specificity of 82% and sensitivity of 61.9%. When this analysis was restricted to biopsies obtained in the first month posttransplantation, the sensitivity increased to 81.8%, but the specificity decreased to 76.9%. After the first month posttransplantation, we observed sensitivity of 40.0% and a specificity of 86.4%. In the first month posttransplantation, all patients with a diagnosis of acute antibody-mediated rejection displayed circulating anti-HLA class I/II, but not always at the same time as the C4d-positive biopsy.

CONCLUSIONS

In the first month posttransplantation, prospective monitoring of anti-HLA antibodies may be useful. The high sensitivity allows the identification of patients at risk, affording an earlier diagnosis of antibody-mediated rejection. After the first month, the test can be used to evaluate allograft dysfunction episodes, since positivity is highly suggestive of an antibody-mediated process.

Whole blood glutathione peroxidase and erythrocyte superoxide dismutase activities, serum trace elements (Se, Cu, Zn) and cardiovascular risk factors in subjects from the city of Ponta Delgada, Island of San Miguel, The Azores Archipelago, Portugal

Activities of whole blood glutathione peroxidase (GSH-Px) and erythrocyte superoxide dismutase (SOD) and serum levels of selenium (Se), copper (Cu) and zinc (Zn) were measured in 118 apparently healthy subjects aged 20-60 years from the city of Ponta Delgada, Island of San Miguel, The Azores Archipelago, Portugal. Data were analysed by age/gender, lipid profile and blood pressure as cardiovascular risk factors searching for their relevance when assessing reference values for antioxidant biomarkers. GSH-Px was in the same range, but SOD was significantly lower than in other Portuguese populations. Neither activity differed with gender. GSH-Px activity increased with age, namely in normolipidemic men versus the hyperlipidemic group in which a decrease was observed. This suggests a progressive impairment of GSH-Px with age caused by an enhanced production of oxidant species in hyperlipidemia. GSH-Px was 30% lower in male hypertensives versus normotensives. SOD activity did not relate to age or blood pressure but was 17% higher in the hyperlipidemic men versus the normolipidemic group, suggesting a better antioxidant protection by SOD than by GSH-Px in hyperlipidemia and hypertension. Se was higher in men versus women, particularly in the older subjects, and partly related to hyperlipidemia. Zn levels showed a similar dependency on gender, not related to age or lipid profile. Cu levels were much higher in women than in men in all age or lipid profile classes and decreased in hyperlipidemia. They were lowered with age in both genders, particularly in normolipidemic women. The present research therefore suggests that hyperlipidemia and hypertension do affect antioxidant status and should be considered when assessing antioxidant biomarkers in blood.

Systemic markers of the redox balance in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is highly prevalent and its pathogenesis is still not completely clarified. Clinically stable patients (n=21) and healthy subjects (n=24) were studied for blood markers of oxidative injury and antioxidant status. The plasma concentration of protein carbonyls was significantly increased in COPD patients, both ex-smokers (0.76 +/- 0.28 nmol mg(-1)) and smokers (0.99 +/- 020 nmol mg(-1)) versus controls (0.49 +/- 0.14 nmol mg(-1)) . The concentration of total thiols was slightly enhanced in plasma of the COPD patients (ex-smokers 492 +/- 23 micromol 1(-1) and smokers 505 +/- 36 micromol 1(-1) versus controls 450 +/- 67 micromol 1(-1); p < 0.05). The activity of the antioxidant enzyme superoxide dismutase was increased in erythrocytes (activity in U g(-1) haemoglobin; ex-smokers 4460 +/- 763 and smokers 4114+/- 1060 versus 3015 +/- 851 in controls; p > 0.01), while glutathione peroxidase activity was decreased in total blood (activity in U g(-1) haemoglobin: ex-smokers 27 +/- 9 and smokers 23 +/- 9 versus 47 +/- 25; p < 0.01). Lower levels of selenium in plasma were also found for COPD patients (concentration in mg 1(-1): ex-smokers 0.030 +/- 0.019 and smokers 0.032 +/- 0.024 versus 0.058 +/- 0.023 in controls; p < 0.01), being more evident in those with very low levels of arterial oxygen pressure. In addition, the levels of potassium and rubidium were increased in blood cells of the patient group. All these changes might reflect oxidant damage and an altered electrolytic homeostasis, and can be interpreted as markers of COPD rather than as indicators of smoking habits.

Optimization of random searches on defective lattice networks

We study the general problem of how to search efficiently for targets randomly located on defective lattice networks--i.e., regular lattices which have some fraction of its nodes randomly removed. We consider large but finite triangular lattices and assume for the search dynamics that the walker chooses steps lengths lj from the power-law distribution P(lj) approximately lj(-mu) , with the exponent mu regulating the strategy of the search process. At each step lj, the searcher moves in straight lines and constantly looks within a detection radius of vision rv for the targets along the way. If there is contact with a defect, the movement stops and a new step length is chosen. Hence, the presence of defects decreases the efficiency of the overall process. We study numerically how three different aspects of the lattice influence the optimization of the search efficiency: (i) the type of boundary conditions, (ii) the concentration of targets and defects, and (iii) the category or class of search--destructive, nondestructive, or regenerative. Motivated by the results, we develop a type of mean-field model for the problem and obtain an analytical approximation for the search efficiency function. Finally we discuss, in the context of searches, how defective lattices compare with perfect lattices and with continuous environments.

Origin of power-law distributions in deterministic walks: the influence of landscape geometry

We investigate the properties of a deterministic walk, whose locomotion rule is always to travel to the nearest site. Initially the sites are randomly distributed in a closed rectangular (ALxL) landscape and, once reached, they become unavailable for future visits. As expected, the walker step lengths present characteristic scales in one (L-->0) and two (AL approximately L) dimensions. However, we find scale invariance for an intermediate geometry, when the landscape is a thin striplike region. This result is induced geometrically by a dynamical trapping mechanism, leading to a power-law distribution for the step lengths. The relevance of our findings in broader contexts--of both deterministic and random walks--is also briefly discussed.

An assessment of time-dependent effects of lead exposure in algerian mice (Mus spretus) using different methodological approaches

Time-dependent effects of lead (Pb) toxicity were studied in Algerian mice (Mus spretus) treated with Pb acetate via drinking water (1 g Pb acetate/L) for different periods of exposure (15, 45, and 90 d). End points included the determination of hepatic Pb concentration and the assessment of some morphophysiological, biochemical and cytogenetical parameters. A control group receiving distilled water was also monitored for comparative purposes. Hepatic Pb accumulation increased with the time of exposure and was significantly higher in treated mice when compared to controls. In association with significant body mass loss in Pb-exposed mice, for 15 and 45 d, a significant increase in the relative spleen mass was observed after 45 d of intoxication. Pb-exposed mice also showed significant decreases in red blood cells, hematocrit, and mean corpuscular hemoglobin. On the contrary, changes in plasma transferases (aspartate aminotransferase and alanine aminotransferase) and hepatic superoxide dismutase activities did not reach statistical significance. A significant increase in the frequency of micronucleated polychromatic bone marrow erythrocytes was also found in the 90-d-exposed mice, compared to nontreated mice and the other exposed groups. Exposure to Pb acetate resulted also in a slight time-dependent decrease of the polychromatic-normochromatic ratio. These results support the concept that a long-term chronic exposure to Pb induced alterations upon some morphophysiological and genetic parameters in Algerian mice.

Optimization of random searches on regular lattices

We investigate random searches on isotropic and topologically regular square and triangular lattices with periodic boundary conditions and study the efficiency of search strategies based on a power-law distribution P() approximately (-mu) of step lengths . We consider both destructive searches, in which a target can be visited only once, and nondestructive searches, when a target site is always available for future visits. We discuss (i) the dependence of the search efficiency on the choice of the lattice topology, (ii) the relevance of the periodic boundary conditions, (iii) the behavior of the optimal power-law exponent mu(opt) as a function of target site density, (iv) the differences between destructive and nondestructive environments, and finally (v) how the results for the discrete searches differ from the continuous cases previously studied.

Determination of dopamine in synthetic cerebrospinal fluid by SWV with a graphite?polyurethane composite electrode

This work describes an electroanalytical investigation of dopamine using cyclic voltammetry (CV) and the graphite-polyurethane composite electrode (GPU). In CV studies, well-defined redox peaks characterize the oxidation process at the GPU electrode, which is indicative of electrocatalytic effects associated with active sites on the GPU electrode surface. A new analytical methodology was developed using the GPU electrode and square wave voltammetry (SWV) in BR buffer solution (0.1 mol L(-1); pH 7.4). Analytical curves were constructed under optimized conditions (f=60s(-1), DeltaE(a)=50 mV, DeltaE(I)=2 mV) and detection and quantification limits of 6.4x10(-8) mol L(-1) (12.1 microg L(-1)) and 5.2x10(-6) mol L(-1) (0.9 mg L(-1)), respectively, were achieved. The precision of the method was checked by performing ten successive measurements for a 9.9x10(-6) mol L(-1) dopamine solution. For intra-assay and inter-assay precisions, the relative standard deviations were 1.9 and 2.3%, respectively. In order to evaluate the developed methodology, the determination of dopamine was performed with good sensitivity and selectivity, without the interference of ascorbic acid in synthetic cerebrospinal fluid, which indicates that the new methodology enables reliable analysis of dopamine.

Trace element status (Se, Cu, Zn) in healthy Portuguese subjects of Lisbon population: a reference study

Serum levels of selenium, copper, and zinc were systematically determined in healthy subjects of the Lisbon population. The sample consisted of 183 blood donors of both genders who were divided into two age groups: 20-44 and 45-70 yr of age; relationships with gender, age, the lipid profile, and tobacco consumption were investigated. In the female group, the intake of oral contraceptives and pregnancy were considered for the youngest women, and hormonal replacement therapy (HRT) was taken into account for the oldest ones. Serum concentrations of these elements were in the same range as those found for populations of other European countries. Differences between genders were observed for the three elements studied, with serum selenium and zinc concentrations higher in men and copper levels higher in women. Age-dependent differences were found for selenium: The oldest subjects (regardless gender) presented the highest concentrations of selenium in serum as further demonstrated by the positive correlation with age. In both pregnant and contraceptive-using women, copper was greatly increased, confirming the influence of estrogen status and/or oral contraceptive intake on increased serum copper levels. However, in postmenopausal women, HRT did not significantly affect serum copper levels. Selenium, copper, and zinc status were not different between normolipidemic and hyperlipidemic subjects for the same gender and age range, but selenium levels tended to increase with hyperlipidemia when considering the whole group of subjects. With respect to the lifestyle, higher serum zinc levels were found in tobacco-consuming men. Albumin serum levels were similar for all considered subgroups, except for the pregnant women, for whom a decrease in this parameter was observed. The present study allowed one to obtain reference values for this healthy group of population, which will serve for a comparative study with groups having pathological conditions, such as cardiovascular disease.

Dynamical robustness of Lévy search strategies

We study the role of dynamical constraints in the general problem of finding the best statistical strategy for random searching when the targets can be detected only in the limited vicinity of the searcher. We find that the optimal search strategy depends strongly on the delay time tau during which a previously visited site becomes unavailable. We also find that the optimal search strategy is always described for large step lengths l by a power-law distribution P(l) approximately l(-mu), with 1<mu(tau)</=2. Our findings appear to remain valid even if arbitrary energy costs of locomotion are considered.

Hepatic elemental contents and antioxidant enzyme activities in Algerian mice (Mus spretus) inhabiting a mine area in central Portugal

In this study the effects of heavy metals (manganese, iron, copper, zinc) and selenium exposure on the hepatic activity of antioxidant enzymes, superoxide dismutase (SOD) and glutathione S-transferases (GST), were appraised on a seasonal basis in Algerian mice (Mus spretus) inhabiting an active copper mine area. A reference population of the same species was considered for comparative purposes. Different patterns of seasonal variation were found in both populations for the manganese, iron and selenium hepatic concentrations and SOD activity. When the two populations were compared, iron and selenium concentrations were enhanced in mice from the polluted area. In addition, SOD activity was significantly decreased in summer in exposed mice, but no other significant changes in SOD and GST activities between sites throughout the year were recorded. However, when seasonal data within each group of mice were pooled, significant differences were found between sites for the average concentrations of manganese, iron and selenium, which are higher in the polluted site. In addition, significant differences were obtained for the average values of SOD and of GST activities, due to simultaneously higher GST values and slightly lower SOD values in the polluted site. The population from the reference site was more homogeneous for all parameters measured than the population from the polluted area. These results, in particular the higher variability in data collected from mice exposed to heavy metals and selenium, combined with the negative associations between biochemical markers and heavy metals, may suggest, despite the good adaptability of the mice to their habitat, biochemical stress due to diminished environmental quality.

Soil chemical changes under irrigated mango production in the Central São Francisco River Valley, Brazil

Irrigated areas in Brazil's Central São Francisco River Valley have experienced declines in productivity, which may be a reflection of changes in soil chemical properties due to management. This study was conducted to compare the chemical composition of soil solutions and cation exchange complexes in a five-year-old grove of irrigated mango (Mangifera indica L. cv. Tommy Atkins) with that of an adjacent clearing in the native caatinga vegetation. A detailed physiographic characterization of the area revealed a subsurface rock layer, which was more undulating than the current land surface, and identified the presence of a very saline and sodic (1045 microS cm(-1), sodium adsorption ratio [SAR] = 5.19) ground water table. While changes in concentrations of Ca, Mg, and K could be attributed to direct management inputs (fertilization and liming with dolomite), increases in Na suggested average annual capillary rise from the ground water table of 28 L m(-2). Accordingly, soil salinity levels appeared to be more dependent on surface elevation than the elevation of the rock layer or sediment thickness. The apparent influence of land surface curvature on water redistribution and the solution chemistry was more pronounced under irrigated mango production. In general, salinity levels had doubled in the mango grove and nearly tripled under the canopies, after only five years of irrigation. Though critical saline or sodic conditions were not encountered, the changes observed indicate a need for more adequate monitoring and management of water and salt inputs despite the excellent water quality of the São Francisco River.

Specific immunotherapy for severe latex allergy

We studied 4 patients (3 adult females + 13y old boy) with latex allergy. All patients had anaphylaxis related with latex and oral-latex-fruit syndrome. All 3 females had severe symptoms in the workplace. The boy had spina bifida with 9 previous surgeries and needed further surgical interventions. Positive skin prick tests (SPT), the presence of serum latex specific IgE (CAP-RAST, Pharmacia-Upjohn, Sweden- class 3 in the 3 females and class 4 in the boy) demonstrated the sensitisation. All 4 patients were treated with specific immunotherapy (SIT) with aqueous extract (ALK-ALK-ABELLO SA, Spain) administered subcutaneously at the hospital, by a modified rush schedule. A maintenance dose (MD) of 0.35_g protein was established according to the magnitude of local reactions (LRs). In one patient a higher dose induced the appearance of a systemic reaction (SR) 40 min after administration, which promptly remitted with treatment. After reaching MD, all 3 females remained assymptomatic at workplace. A challenge test with latex gloves was performed. Two months after MD was reached 2 females had no symptoms and one other had mild symptoms of rhinoconjunctivitis. The boy was subjected to a surgical intervention with no allergic reaction. We also observed a reduction on skin reactivity to latex in all patients by prick tests. We consider SIT with latex to be highly effective, safe and well tolerated provided we use this dose of the allergenic extract.

Peritoneal fluid concentrations of interleukin-8 in patients with endometriosis depend on the severity of the disorder and are higher in the luteal phase

BACKGROUND

Previous evaluations of the relationship between the concentrations of interleukin-8 (IL-8) in the peritoneal fluid and endometriosis led to non-consistent results. Our purpose was to investigate the correlation of the concentrations of IL-8 in the peritoneal fluid with the stage of endometriosis, the presence of red lesions and the phase of the menstrual cycle.

METHODS

Ninety-two patients with infertility (n = 87) or undergoing sterilization (n = 5) had peritoneal fluid samples collected at laparoscopy. IL-8 determinations were performed using an enzyme-linked immunosorbent assay.

RESULTS

The concentrations of IL-8 in the peritoneal fluid of the 68 women with endometriosis were not significantly different from those of the 24 controls. Patients with moderate/severe stages had IL-8 significantly higher than controls (P = 0.008) and marginally higher than patients with minimal/mild endometriosis (P = 0.053). Concentrations of IL-8 were significantly higher in patients than in controls in the luteal phase. Red lesions were associated with significantly increased levels of peritoneal fluid IL-8 only in the luteal phase.

CONCLUSIONS

Our findings reinforce the importance of IL-8 in the pathogenesis of endometriosis.

Soluble intercellular adhesion molecule 1 in the peritoneal fluid of patients with endometriosis correlates with the extension of peritoneal implants

OBJECTIVE

To investigate the correlation of the concentrations of soluble intercellular adhesion molecule 1 (sICAM-1) in the peritoneal fluid (PF) with the extent of peritoneal endometriotic lesions and with the presence of red lesions (RLs).

STUDY DESIGN

Sixty-seven patients with endometriosis and 19 controls with normal pelvis had PF samples collected during laparoscopy.

RESULTS

The concentrations of sICAM-1 in the PF of patients and controls were not different. Patients with peritoneal implant scores 4 or more had higher concentrations of sICAM-1 in the PF than those with implant scores less than 4 (P=0.018) and controls (P=0.031). No significant difference was found in sICAM-1 levels in patients with and without RLs. No correlation was detected between sICAM-1 and interleukin 1beta (IL-1beta) in either patients or controls.

CONCLUSIONS

The increased concentrations of sICAM-1 in the PF of patients with greater implant scores may indicate an active shedding of the molecule from the endometriotic peritoneal tissue. No significant association was found with the presence of RLs. The levels of IL-1beta in the PF were not a relevant factor influencing the concentrations of sICAM-1.

Response of antioxidant enzymes in freshwater fish populations (Leuciscus alburnoides complex) to inorganic pollutants exposure

Evidence is accumulating indicating the importance of antioxidant enzyme activity measurements in eco-toxicological studies, as they may constitute markers for exposure to a large variety of pollutants. Variation of antioxidant enzymes, superoxide dismutase (SOD) and glutathione S-transferases (GST) and the effect of heavy metals and selenium exposure on these enzymes were investigated in the livers of Iberian endemic minnows (Leuciscus alburnoides complex) captured in a copper (Cu) mining area. Higher hepatic levels of copper and selenium were always observed in fish captured at the polluted site relative to the reference area population, reflecting the environmental monitoring results. A seasonal fluctuation in zinc and selenium levels for both populations was also observed which could be related to gonad maturation. The activity of SOD did not show significant regional alterations, but a seasonal variation occurred presumably associated with the Leuciscus life cycle. The GST activity was higher in the fish population from the polluted area (except in spring) and GST variability was associated with selenium and copper levels when both regions were compared. The increased GST activity was probably a metabolic adaptation to the continuous exposure to higher levels of those elements.

Effect of specific immunotherapy versus loratadine on serum adhesion molecules

OBJECTIVE

To evaluate comparatively the effect on serum ICAM-1 and VCAM-1 values of specific immunotherapy versus loratadine in the treatment of allergic rhinitis.

POPULATION

65 patients with mild to moderate House Dust Mite allergic rhinitis.

METHODS

Patients were divided into three groups, according to patients' preference: a control group with patients receiving only rescue therapy (antihistamines and/or nasal cromoglycate when needed); an antihistamine group with patients receiving daily loratadine 10 mg (and nasal cromoglycate as rescue therapy); an immunotherapy group with patients receiving subcutaneous house dust mite specific immunotherapy (and antihistamines or nasal cromoglycate when needed). In all groups we measured soluble ICAM-1 and VCAM-1 serum levels before the start of the study period and at the end of the study period. The duration of the study was one year for the control group and for the immunotherapy group. In patients taking daily antihistamines we measured serum adhesion molecules one month after the beginning of the therapy. We used Student's T test for statistical analysis.

RESULTS

Patients in the control group didn't have significant variations in serum ICAM-1 (p = 0.239) or VCAM-1 (p = 0.38) levels. Patients receiving loratadine showed significant decreases in serum VCAM-1 levels (p = 0.0012) but not in serum ICAM-1 levels (p = 0.224). Patients receiving immunotherapy also showed a similar pattern, with significant decreases in serum VCAM-1 levels (p = 0.012) but not in serum ICAM-1 levels (p = 0.254).

CONCLUSIONS

Specific house dust mite immunotherapy and regular daily loratadine therapy are able to lower significantly serum levels of soluble VCAM-1. However, this effect, which can be interpreted as an anti-inflammatory action, is not applied to soluble ICAM-1 levels, which raises the possibility of a differential action of these therapies on the mechanisms of allergic inflammation. Patients on rescue medication alone did not show any significant differences in these parameters.

Immunotherapy in allergic rhinitis

Allergen specific immunotherapy (IT) represents a cornerstone of allergic rhinitis treatment and his efficacy has been confirmed, through open and double blind trials and meta-analysis. In the last few years non invasive routs for IT (oromucosal, nasal) were developed gained general acceptation mainly in children and were validated by WHO. The efficacy of IT could be markers, the pattern of specific antibody response or by the effect on sequential nasal challenges. We have evaluated the effect of IT in allergic rhinitis by different methods. Nasal IT decreased mean symptoms and pharmacological scores as well as in seasonal as in perennial rhinitis. The same decrease has been observed after oromucosal IT. The effect of IT in allergic inflammation has been confirmed by a decrease in the level of soluble adhesion molecule sVCAM-1 which is related to eosinophilic inflammation but not statistically for sICAM-1. We have also evaluated the immunoblotting pattern or specific IgE after oromucosal IT for house dust mites. For D. pteronyssinus in 4 patients the bands intensity decreased and in 3 patients the bands decreased and in 10 disappeared. IT decreases tryptase and ECP in nasal lavage after sequential nasal challenges. Therefore IT decreases clinical scores, inflammation markers, specific IgE immunoblotting bands and response to allergen challenge. These different results confirm his efficacy and usefulness in allergic rhinitis.

Origin of quantum chaos for two particles interacting by short-range potentials

We address the problem of two confined one-dimensional particles of arbitrary masses interacting by general short-range potentials. We study under what conditions quantum chaos emerges for the system by analyzing its spectrum statistics. We show that these conditions are directly connected with a specific feature of the underlying classical dynamics, namely, the ergodicity in the changes of the particles momenta. Quantum mechanically this prevents one from obtaining the exact wave function through the Bethe ansatz. Possible extensions for many-body systems are also discussed.

Tumour necrosis factor alpha concentrations in the peritoneal fluid of infertile women with minimal or mild endometriosis are lower in patients with red lesions only than in patients without red lesions

Tumour necrosis factor alpha (TNFalpha) of peritoneal fluid is believed to have important pro-inflammatory and angiogenic activities in the complex mechanisms of development of peritoneal endometriotic lesions. We have evaluated the concentrations of TNFalpha and macrophages in peritoneal fluid of infertile women with minimal or mild endometriosis and related them to the presence of peritoneal red lesions alone (red lesions only group; n = 11) or their absence (non-red lesions group; n = 36). A group of 39 infertile normo-ovulatory patients with normal pelvic anatomy was used as controls. TNFalpha concentrations did not differ between controls and either group of patients. Patients with red lesions only had significantly lower concentrations of TNFalpha in peritoneal fluid (P < 0.05) and had a higher proportion of samples with undetectable concentrations (P < 0.05) than patients without red lesions. The significant difference in TNFalpha concentrations was present when comparing the groups of patients in the proliferative phase but not in the secretory phase. Macrophage concentrations were not different in the groups. Our findings are compatible with an impairment of macrophage function and therefore lend support to the theory that an inappropriate immunological response of the peritoneal environment to regurgitated endometrium may play a part in the initial phases of endometriotic implants.

Trace element status (Se, Cu, Zn) and serum lipid profile in Portuguese subjects of San Miguel Island from Azores'archipelago

Data on selenium, copper and zinc in serum of Portuguese inhabitants of the city of Ponta Delgada-Azores Archipelago are reported for the first time. The subjects are of both sexes, aged 20 to 60 years, and non-abusers of alcohol, tobacco or drugs. Serum concentrations of these elements are in the same range than those found for populations of Lisbon and of some other European countries. Differences between sexes are observed, with serum selenium and zinc levels being higher in males than in females, and the copper levels being higher in females as compared to males. These results can be explained by the hormonal status and/or oral contraceptive steroids intake, particularly for copper. Concerning lipid profile, the majority of individuals have serum lipid parameters within the normal range. In addition, no difference in trace element levels between normo and hyperlipidemic individuals is observed and no conclusive results about the relationship of all evaluated parameters to alcohol, tobacco and drug consumption are observed, in agreement with data obtained in the population of Lisbon.

Combination of clinical factors predictive of growth of small choroidal melanocytic tumors

OBJECTIVE

To better define the effect of individual risk factors and combinations thereof on the growth of small choroidal melanocytic tumors.

DESIGN

Retrospective analysis.

SETTING

Clinical practice of ocular oncology.

PATIENTS

The study included 1287 patients with small suspicious choroidal melanocytic tumors, measuring 3 mm or less in thickness, managed with observation.

RESULTS

On multivariate analysis, the clinical risk factors predictive of growth of small choroidal melanocytic tumors include tumor thickness greater than 2.0 mm, posterior tumor margin touching the disc, visual symptoms, orange pigment, and subretinal fluid. Tumor growth was detected in 4% of those patients with no risk factors. Growth was detected in approximately 36% of patients with 1 risk factor, 45% of patients with 2 risk factors, 50% of patients with 3 risk factors, 51% of patients with 4 risk factors, and 56% of patients with all 5 risk factors. The combination of risk factors offering the greatest risk for growth was tumor thickness greater than 2.0 mm, tumor margin touching disc, and subretinal fluid that was associated with tumor growth in 63% of the affected patients. The relative risk for growth was 1.9 for 1 factor, 3.8 for 2 factors, 7.4 for 3 factors, 14.1 for 4 factors, and 27.1 for all 5 risk factors combined.

CONCLUSIONS

Five risk factors for growth of small choroidal melanocytic tumors have been identified. The combinations of various factors increase the risk for tumor growth from 4% if no factors are present to more than 50% if 3 or more risk factors are present. These factors may be important when counseling patients with small suspicious choroidal melanocytic tumors.

[Ocular manifestations in HIV infected patients attending the department of ophthalmology of Universidade Federal de São Paulo]

PURPOSE

To evaluate ocular manifestations of HIV-infected patients.

MATERIAL AND METHODS

A retrospective study of 1,100 HIV positive out patients in 3 years with a standard complete ophthalmological exam.

RESULTS

Eight hundred and sixty nine (79%) of the 1,100 patients studied were male and 231 (21%) female. The most important risk factors were: male homosexuality in 303 cases (27.55%), heterosexuality in 272 (24.73%), endovenous drugs use in 168 (15.27%), and unknown cause in 246 (26.36%). Related to ocular complains, we found 432 (39.27%) patients with decreased visual acuity, 138 (12.55%) with visual hazy, 64 (5.82%) with ocular pain, 186 (16.9%) with inspecific complaints, and 235 (21.36%) with no complains. The most frequent ocular manifestations were: CMV retinitis in 246 (22.36%), cotton wool spots in 110 (10%), blepharitis in 51 (4.64%), and toxoplasmosis in 48 (4.36%).

CONCLUSION

The increase of disease ratio was observed among heterosexual and females in this specific population. Patients with ocular complains were 79.42%. The most frequent ocular manifestations was CMV retinitis, in 246 (22.36%). We found also 10% of cotton wool spots.

Nasal provocation and immunotherapy

Nasal mucosa is heavily exposed to inflammatory and allergic stimuli, rhinitis being the most common form of allergic respiratory disease. The nose is an easily accessible organ and a good model for the study of allergies as it makes it possible to monitor the effects of specific challenges as well as therapeutic interventions, namely specific immunotherapy (SIT). Injectable, nasal or sublingual SIT are useful therapeutic strategies in the management of allergic rhinitis patients. Monitoring the evolution of parameters such as clinical scores, nasal peak flow variation or drug requirements during SIT provides important information on its clinical efficacy. Laboratory measurement of tryptase and eosinophil cationic protein in the target organ after specific nasal provocation makes it possible to record changes in the release of mast cell and eosinophil mediators, thus providing objective evidence of the immunological efficacy of this therapy on these cell populations and providing data which eventually will contribute to a better understanding of the multiple mechanisms of action of allergen desensitization therapy.

Thermotherapy for retinoblastoma

OBJECTIVE

To evaluate the results of thermotherapy for retinoblastoma.

DESIGN

Prospective, nonrandomized analysis of the treatment method.

PARTICIPANTS

A total of 188 retinoblastomas in 80 eyes of 58 patients who were treated with thermotherapy.

MAIN OUTCOME MEASURES

Tumor response and ocular adverse effects.

RESULTS

Of 188 retinoblastomas treated with thermotherapy, mean tumor base was 3.0 mm and tumor thickness was 2.0 mm. Complete tumor regression was achieved in 161 tumors (85.6%), and 27 tumors (14.4%) developed recurrence. Using univariate analysis, the predictors of local tumor recurrence were male sex (P = .005), no color change ("no visible take") in tumor after treatment (P = .01), increasing number of treatment sessions (P = .002), and previous use of chemoreduction (P = .02). By multivariate analysis, the most important predictors of local tumor recurrence were male sex (P = .01) and previous use of chemoreduction (P = .03), the latter likely reflecting the fact that these tumors were initially larger with more ominous findings, and required chemoreduction therapy to reduce them to a size amenable to focal treatment with thermotherapy. When evaluating thermotherapy variables as a function of tumor size, it was apparent that larger tumors (> or =3.0-mm base) required greater energy and time than did smaller tumors (<3.0-mm base). Comparison of treatment variables for larger vs smaller tumors was as follows: number of treatment sessions, 3.3 vs 2.3; spot size, 1.7 vs 1.3 mm; power, 540 vs 370 mW; treatment duration, 49 vs 14 minutes; and coupling of thermotherapy with chemotherapy, 79% vs 48% of cases (P < or =.001 for each variable). Complications of thermotherapy in the 80 eyes included focal iris atrophy in 29 eyes (36%), peripheral focal lens opacity in 19 eyes (24%), retinal traction in 4 eyes (5%), retinal vascular obstruction in 2 eyes (2%), and transient localized serous retinal detachment in 2 eyes (2%). There were no cases of corneal scarring, central lens opacity, iris or retinal neovascularization, or rhegmatogenous retinal detachment. All eyes with focal lens opacity demonstrated adjacent focal iris atrophy. By multivariate analysis, the predictors of thermotherapy-induced focal iris atrophy were increasing number of treatment sessions (P = .001) and increasing tumor base (P = .02).

CONCLUSIONS

Thermotherapy is used for relatively small retinoblastomas without associated vitreous or subretinal seeds. This treatment provides satisfactory control for selected retinoblastomas, with 86% of tumors demonstrating lasting regression. Tumors that measure 3.0 mm or larger in base at the time of thermotherapy require more intense treatment than smaller tumors and are at greatest risk for ocular complications such as focal iris atrophy and focal paraxial lens opacity.

Primary Swenson pull-through compared with multiple-stage pull-through in the neonate

BACKGROUND

In Hirschsprung's disease, the trend has been for earlier performance of definitive surgery. In our institution, primary Swenson pull-through has become the preferred procedure.

METHODS

Retrospective review of the patients treated for Hirschsprung's disease from January 1988 through March 1998 was performed. Sixty-five patients were identified. Median values, analysis of variance and x2 were used for comparisons.

RESULTS

The multiple-stage group (M, n = 47) was similar to the primary group (P, n = 18) for gestational age (40 v 39 weeks), time to meconium passage (37.9 v 35.5 hours), and age at diagnosis (median, M 27 vP 3.5 days). Age (median, M 268 vP 5 days) and weight (mean, M 9.4 v P 3.7 kg; P < .001) at pull-through were lower in the primary group. Length of stay (LOS) was lower in the primary group (mean, M 40.8 vP 20.3 days; P < .05). Operating time for pull-through was decreased in P (mean, M 305.2 v P 272.2 minutes; P = .02). Total complications were lower in the primary group (P = .03), with no differences in mortality or enterocolitis rates.

CONCLUSIONS

At our institution there were no increases in total complications or enterocolitis in the group undergoing primary Swenson. Primary pull-through is a viable option for the treatment of Hirschsprung's disease.

Extraocular extension of unrecognized choroidal melanoma simulating a primary optic nerve tumor: report of two cases

BACKGROUND

Orbital extraocular extension of choroidal melanoma is well known and is usually detected in eyes with medium and large tumors, but it is very rare with small melanomas. It is particularly unusual for choroidal melanomas of any size to invade the optic nerve or its meninges.

DESIGN

Two case reports.

PARTICIPANTS

Two patients with small, relatively inconspicuous juxtapapillary pigmented choroidal lesions were referred with the diagnosis of primary optic nerve tumor. Both demonstrated a large nodular tumor in the meninges of the optic nerve, immediately posterior to the globe.

METHODS

Retrospective review of clinical records and histopathology.

RESULTS

In both cases, orbital magnetic resonance imaging confirmed the presence of a hyperintense enhancing nodular mass near the anterior portion of the optic nerve, prompting optic nerve biopsy in one case. Subsequent fundus examination disclosed a small juxtapapillary pigmented choroidal lesion measuring 1.0 mm or less in thickness. These observations suggested that the optic nerve tumor might be nodular extraocular extension of a small choroidal melanoma. Modified enucleation was performed in both cases, and histopathologic examination revealed a nodule of malignant melanoma within the meninges that compressed the optic nerve and extended extraocularly from a small, relatively inapparent juxtapapillary choroidal melanoma. In both cases, the extraocular component was large and symptomatic, whereas the intraocular component was inconspicuous.

CONCLUSIONS

Small juxtapapillary choroidal melanomas can exhibit prominent extension into the orbit. All patients with orbital tumors should have careful ophthalmoscopy.

Interleukin-1 mediates hemodynamic dysfunction and release of eicosanoids and tumor necrosis factor during graded bacteremia

The pathophysiologic events of sepsis mediated by interleukin-1 (IL-1) remain ill-defined. The purpose of this study was to identify the circulatory derangements of which IL-1 was a necessary mediator and evaluate its interactions with tumor necrosis factor (TNF) and the eicosanoids during graded bacteremia. Eleven adult female swine were anesthetized, mechanically ventilated, and monitored with pulmonary artery catheters and arterial lines; they received intravenously either saline vehicle (septic control, n = 6) or human recombinant IL-1 receptor antagonist (IL-1ra, n = 5). The animals were then infused with Aeromonas hydrophila (10(9)/mL) for 4 h at rates gradually increased from .2 mL/kg/h to 4 mL/kg/h over 3 h, then sacrificed after 4 h. Mean arterial pressure (MAP), left ventricular stroke work index (LVSWI), and systemic vascular resistance index (SVRI) were recorded at baseline and hourly thereafter, and plasma 6-keto-PGF1alpha (6-KETO), tumor necrosis factor-alpha (TNF) and leukotrienes B4(LTB4) and C4D4E4 (LTCDE), pg/mL, were measured by ELISA. MAP, LVSWI, arterial P(O2) all decreased in the septic control group to levels significantly below those of the IL-1 antagonist animals. Circulating 6-KETO, LTCDE, and TNF increased significantly in all septic animals. Plasma LTB, and TNF were reduced by IL-1 blockade, compared with septic controls. TxB2 was not affected by IL-1 inhibition. There were no intergroup differences in platelet aggregation, but the in vitro aggregation response decreased from baseline in septic controls to 54+/-27% (p < .05). IL-1 is necessary to the development of systemic hypotension impaired LVSWI, and increased intravascular platelet aggregation during graded bacteremia. Conversely, IL-1 helps to maintain stroke volume and low SVRI in graded bacteremia, possibly through increased prostacyclin release. It may contribute to impaired pulmonary gas exchange and increased tissue oxygen demands. TNF release is stimulated in the presence of unopposed IL-1 and may be synergistic with it in the adverse hemodynamic effects of endogenous IL-1. IL-1 is required for increased leukotriene and prostacyclin levels in this model, but it is not involved in thromboxane release. Whether the lack of survival benefit from IL-1ra in human sepsis is due to these mixed cardiopulmonary and mediator effects, to species differences, or to timing of IL-1ra administration is not clear from the data.