Ecology of phlebotomines (Diptera: Psychodidae) in a transitional area between the Amazon and the Cerrado in the State of Maranhão, Brazil.

The Amazon rainforest and the Brazilian Cerrado both possess high phlebotomine diversity. The fragmentation of these habitats has resulted in the appearance of human cases of cutaneous leishmaniasis. In one altered area of mixed primary vegetation (forest and Cerrado) and its adjacent settlement in the northeast state of Maranhão, Brazil, evidence exists for the active transmission of cutaneous leishmaniasis. Accordingly, an entomological investigation was performed in both the forest and the settlement to compare the phlebotomine vector faunain each environment. The study was conducted from September 2009 to August 2010 in the municipality of Itapecuru Mirim in the state of Maranhão, Brazil. The phlebotomine species were captured using 24 light Center for Disease Control and Prevention traps that were placed in the forest and the settlement (peridomicile and intradomicile). The similarity between the phlebotomine compositions in the forest and those in the settlement was determined using a Principal Coordinate Analysis based on a dissimilarity matrix that was calculated using the Bray-Curtis index (relative abundance) and the Jaccard index (presence and absence of species). In total, 29 Lutzomyia species and one Brumptomyia species were collected. The phlebotomines were diverse and abundant in both the forest fragment (27 species, 4,606 specimens) and the settlement (22 species, 753 specimens). The most abundant species were L. infraspinosa (25%), L. davisi (21%), L. antunesi (21%), L. longipalpis (9%), L. saulensis (6%), L. flaviscutellata (5%), and L. wellcomei (4%). Some species were found strictly in the forest, other species were exclusive to the anthropic environment, and some species colonized both of the studied environments. The phlebotomines adaptation to these modified environments explains the autochthonous outbreak of cutaneous leishmaniasis.

Pleural appendages: Description, incidence and relations with body mass index

BACKGROUND AND AIMS: Pleural appendages (PA) are portions of extrapleural fat that hang from the chest wall. They have been described on videothoracoscopy, however their appearance, frequency and possible relationship with the amount of patient's fat remain unknown. Our aim is to describe their appearances and prevalence on CT, and determinate whether their size and number is higher in obese patients. PATIENTS AND METHODS: Axial images of 226 patients with pneumothorax on CT chest were retrospectively reviewed. Exclusion criteria included known pleural disease, previous thoracic surgery and small pneumothorax. Patients were divided in obese (BMI>30) and non-obese (BMI<30) groups. Presence, position, size and number of PA were recorded. Chi square and Fisher's exact test were used to evaluate differences between the two groups, considering p<0.05 as significant. RESULTS: Valid CT studies were available for 101 patients. Extrapleural fat was identified in 50 (49.5%) patients. Most were solitary (n=31). Most were located in the cardiophrenic angle (n=27), and most measured <5cm (n=39). There was no significant difference between obese and non-obese patients regarding the presence or absence of PA (p=0.315), number (p=0.458) and size (p=0.458). CONCLUSIONS: Pleural appendages were seen in 49.5% patients with pneumothorax on CT. There was no significant difference between obese and non-obese patients regarding presence, number and size of pleural appendages.

Extrapleural fat: description, incidence, and relation with body mass index. / Apéndices pleurales: descripción, incidencia y relación con el índice de masa corporal.

BACKGROUND AND AIMS: Pleural appendages (PA) are portions of extrapleural fat that hang from the chest wall. They have been described on videothoracoscopy, however their appearance, frequency and possible relationship with the amount of patient's fat remain unknown. Our aim is to describe their appearances and prevalence on CT, and determinate whether their size and number is higher in obese patients. PATIENTS AND METHODS: Axial images of 226 patients with pneumothorax on CT chest were retrospectively reviewed. Exclusion criteria included known pleural disease, previous thoracic surgery and small pneumothorax. Patients were divided in obese (BMI > 30) and non-obese (BMI < 30) groups. Presence, position, size and number of PA were recorded. Chi square and Fisher's exact test were used to evaluate differences between the two groups, considering p<0.05 as significant. RESULTS: Valid CT studies were available for 101 patients. Extrapleural fat was identified in 50 (49.5%) patients. Most were solitary (n=31). Most were located in the cardiophrenic angle (n=27), and most measured < 5cm (n=39). There was no significant difference between obese and non-obese patients regarding the presence or absence of PA (p=0.315), number (p=0.458) and size (p=0.458). CONCLUSIONS: Pleural appendages were seen in 49.5% patients with pneumothorax on CT. There was no significant difference between obese and non-obese patients regarding presence, number and size of pleural appendages.

Current management of small renal masses. / Manejo actual de las masas renales pequeñas.

One of the consequences of the growing use of diagnostic imaging techniques is the notable growth in the detection of small renal masses presumably corresponding to localized tumors that are potentially curable with surgical treatment. When faced with the finding of a small renal mass, radiologists must determine whether it is benign or malignant, and if it is malignant, what subtype it belong to, and whether it should be managed with surgical treatment, with ablative techniques, or with watchful waiting with active surveillance. Small renal masses are now a clinical entity that require management different from the approaches used for classical renal cell carcinomas. In this scenario, radiologists are key because they are involved in all aspects of the management of these tumors, including in their diagnosis, treatment, and follow-up.

Gastrointestinal perforation caused by ingested fish bone. Computed tomography findings in 58 patients. / Perforación gastrointestinal por espina de pescado. Hallazgos radiológicos en tomografía computarizada en 58 pacientes.

CONTEXT AND OBJETIVE: Fish bones (FB) are the most commonly ingested objects and the most common cause of foreign body perforation of the GI tract. Patients present with varied and nonspecific clinical presentations. The inability to obtain a history of FB ingestion and its wide spectrum of nonspecific clinical presentations makes dietary FB perforation extremely difficult to diagnose, being a laparoscopic or surgical diagnosis. The aim of our study is to describe radiological features in CT that will alert you to look for the FB and then make an accurate presurgical diagnosis. MATERIALS AND METHODS: All patients (n=58) with radiological diagnosis of gastrointestinal perforation caused by fish bone detected by CT between 2007 to 2017 were retrospectively reviewed. Inclusion criteria were: fish bone located beyond the esophagus, radiological diagnosis by CT and confirmation by surgery, endoscopy or radiological control. Descriptive analysis was made. Radiological features were studied including radioopaque foreign body, mural thickness, fatty infiltration or extraluminal air bubbles. Also potential complications were assessed. RESULTS: There were 58 patients, 39 men and 19 women, with an average age of 70. Ileon was the most frequent site of perforation (20 patients). 100% showed regional fatty infiltration, 98% included foreign body, 45% had mural thickening and 20% localized extraluminal air bubbles. 15 abscess were found (3 in the liver) and just 5 showed pneumoperitoneum. CONCLUSION: Fatty infiltration is the feature more common. Therefore, if fatty infiltration is seen in isolation radiologist should look for foreign body.

Segmental arterial mediolysis. / Mediolisis arterial segmentaria.

This article reports the case of a 51-year-old woman in whom brain MRI to follow up multiple sclerosis incidentally discovered an intramural hematoma in the extracranial internal carotid artery. MR angiography of the supra-aortic trunks and CT angiography of the aorta showed arterial dilations, aneurysms, dissections, and intramural hematomas in the internal carotid arteries, vertebral arteries, and arteries in the splanchnic territory. These findings raised suspicion of segmental arterial mediolysis. After 6 months of treatment with antiplatelet drugs, the arterial involvement resolved. Segmental arterial mediolysis is an uncommon disease; low clinical suspicion and radiologists' lack of knowledge about this entity mean that it can go undetected or be confused with other vasculitides. This report describes the most relevant pathophysiological findings and correlates them with the imaging findings.

Bioprospection of Isochrysis galbana and its potential as a nutraceutical.

Microalgae have strong potential as novel sources of nutraceuticals, as they contain significant amounts of highly valuable bioactive compounds. This study focuses on the bioprospection of biomass of the microalga Isochrysis galbana and its extracts (aqueous and ethanolic), determining total polyphenols, laminarin, fucoxanthin, coenzyme Q10, and ß-carotene contents, and also assessing several biological activities (antioxidant, cytotoxicity, and hypocholesterolemic). I. galbana exhibited high phenolic content, both in aqueous and ethanolic extracts. The microalgal freeze-dried biomass presented a low laminarin content and higher content of fucoxanthin (6.10 mg per g dw), and relevant ß-carotene and Coenzyme Q10 contents were detected. I. galbana aqueous extracts presented a high antioxidant capacity (approximately 90% inhibition by the ABTS method). Furthermore, I. galbana biomass and ethanolic extract showed significant cytotoxicity against HeLa human cervical cancer cells, with IC50 values of 0.32 and 0.28 mg ml-1 respectively, demonstrating potential for further anticancer studies. The aqueous extract of I. galbana induced a significant decrease of cholesterol absorption through Caco-2 monolayers, modelling the human intestinal barrier, which suggests that it may contribute to decreasing the dietary cholesterol absorption.

Surveillance of adamantane resistance among influenza A H3 viruses isolated in Argentina between 2001 and 2007.

A dramatic rise in the frequency of resistance to adamantane drugs by influenza A H3 viruses, associated with a single amino acid replacement in the viral matrix M2 protein, has occurred in multiple countries worldwide in recent years. We investigated the frequency of adamantane-resistant influenza A H3 viruses in Argentina during the period 2001-2007. We used reverse transcription followed by polymerase chain reaction. The obtained products were sequenced for the detection of mutations of the M2 gere relevant to the resistance phenotypes. The HA1 sequences of the sensitive and resistant strains were also analyzed to clarify whether they had any relevance to the resistant mutations. Twenty out of 55 (36%) strains were identified with the resistance-conferring substitution at amino acid 31 (Serine 31 Asparagine). No resistant viruses were detected between 2001 and 2005. All strains isolated in 2006 and four out of five isolates from 2007 were resistant. None of the patients had received previous treatment with amantadine and/or rimantadine. The HA1 analysis showed that there were only two changes (Serine193 Phenylalanine and Aspartic acid 225 Asparagine) present in the strains with the M2 substitution at position 31. Our data indicate that since 2006 there has been a significant increase of adamantane-resistant influenza A H3 viruses, which raises concern over the spread of these viruses in Argentina.

The utility of dual-energy CT for metal artifact reduction from intracranial clipping and coiling. / Utilidad de la tomografía computarizada de energía dual en la reducción del artefacto metálico generado por clips y coils intracraneales.

OBJECTIVE: To assess the ability of dual-energy CT (DECT) to reduce metal-related artifacts in patients with clips and coils in head CT angiography, and to analyze the differences in this reduction between both type of devices. MATERIALS AND METHODS: Thirteen patients (6 clips, 7 coils) were selected and retrospectively analized. Virtual monoenergetic images (MEI) with photon energies from 40 to 150 keV were obtained. Noise was measured at the area of maximum artifact. Subjective evaluation of streak artifact was performed by two radiologists independently. Differences between noise values in all groups were tested by using the ANOVA test. Mann-Whitney U test was used to compare the differences between clips and coils. Cohens κ statistic was used to determine interobserver agreement. RESULTS: The lowest noise value was observed at high energy levels (p<0,05). Noise was higher in the coil group than in the clip group (p<0.001). Interobserver agreement was good (κ=0.72). CONCLUSIONS: TCED with MEI helps to minimize the artifact from clips ands coils in patients who undergo head CT angiography. The reduction of the artifact is greater in patients with surgical clipping than in patients with endovascular coiling.

Value of dual-energy CT enterography in the analysis of pathological bowel segments in patients with Crohn's disease. / Valor de la enterografía por tomografía computarizada con doble energía en el análisis de segmentos intestinales patológicos en pacientes con enfermedad de Crohn.

OBJECTIVE: To analyze whether there are significant differences in the objective quantitative parameters obtained in the postprocessing of dual-energy CT enterography studies between bowel segments with radiologic signs of Crohn's disease and radiologically normal segments. MATERIAL AND METHODS: This retrospective study analyzed 33 patients (16 men and 17 women; mean age 54 years) with known Crohn's disease who underwent CT enterography on a dual-energy scanner with oral sorbitol and intravenous contrast material in the portal phase. Images obtained with dual energy were postprocessed to obtain color maps (iodine maps). For each patient, regions of interest were traced on these color maps and the density of iodine (mg/ml) and the fat fraction (%) were calculated for the wall of a pathologic bowel segment with radiologic signs of Crohn's disease and for the wall of a healthy bowel segment; the differences in these parameters between the two segments were analyzed. RESULTS: The density of iodine was lower in the radiologically normal segments than in the pathologic segments [1.8 ± 0.4mg/ml vs. 3.7 ± 0.9mg/ml; p<0.05]. The fat fraction was higher in the radiologically normal segments than in the pathologic segments [32.42% ± 6.5 vs. 22.23% ± 9.4; p<0.05]. CONCLUSION: There are significant differences in the iodine density and fat fraction between bowel segments with radiologic signs of Crohn's disease and radiologically normal segments.

Photoperiod Differences in Sand Fly (Diptera: Psychodidae) Species Richness and Abundance in Caves in Minas Gerais State, Brazil.

Caves are unique habitats that are inhabited by a diverse and singular biota. Among these inhabitants are sand flies, which are of great epidemiological interest in the Neotropical region because they are vectors of Leishmania The period of activity of these insects is usually crepuscular and nocturnal, but there are reports of diurnal activity of sand flies in caves. Thus, the aim of this study was to evaluate the periodicity of daily activity of sand flies in cave environments in the municipality of Pains, Minas Gerais. Sand flies were collected with light traps, which were operated for 5 consecutive days in the rainy season and in the dry season. Samples were collected every 12 h and separated between photophase and scotophase periods. In total, 1,777 sand flies of 23 species were collected. The most abundant species was Lutzomyia renei (Martins, Falcão, and Silva) (44%), followed by Lutzomyia longipalpis (Lutz and Neiva) (15%), Evandromyia edwardsi (Mangabeira) (11%), and Micropygomyia quinquefer (Costa Lima) (6%). The richness and abundance of total sand flies and the abundance of male and female sand flies in the aphotic zone of the caves did not differ between the photophase and scotophase, but differed between photoperiods at the entrance and at sites surrounding the caves. From our study of the daily activity of these insects in this ecotope, it will be possible to know which period of the day is of greatest risk of exposure of vertebrates who visit or live in these environments, including the human population.

Psoralen analogues: synthesis, inhibitory activity of growth of human tumor cell lines and computational studies.

Eight psoralens have been evaluated for their ability to inhibit the in vitro growth of three human tumor cell lines representing different tumor types, MCF-7 (breast cancer), NCI-H460 (non-small cell lung cancer) and SF-268 (CNS cancer). The synthesis of four new psoralens (benzofurocoumarins) is presented as well as the results of the ab initio calculations to find the parameters that relate the structure with the antitumor activity. This work provides supplementary information that could allow the development of new psoralen analogues with this type of biological activity.

Charge reduction in a vermiculite by acid and hydrothermal methods: a comparative study.

A comparative study on acid and hydrothermal methods as ways to reduce interlamellar charge has been carried out on a vermiculite. This study showed that the application of the hydrothermal treatment as a previous step to pillaring the vermiculites, reported here for the first time, is a new route to obtain the porous material with a particular interest as heterogeneous catalysts, starting from mineral clays with a high density of charge. Modified clays have been characterized by atomic absorption, emission spectrograph, X-ray diffraction, cation-exchange capacity, total acidity, infrared spectroscopy (DRIFT), and nitrogen adsorption. The results have shown that all solids have been structurally modified. However, acid and hydrothermal methods showed different behavior. For the vermiculite, the hydrothermal treatment did not produce major differences in terms of the crystalline structure, whereas the acid method caused severe structural damage. The catalytic properties have been tested over Pt-impregnated samples (1%) using the hydroisomerization of heptane. Important catalytic activity was established for all solids with high selectivity regarding the isomer products.

Role of endogenous channels in red blood cells response to their exposure to the pore forming toxin Sticholysin II.

Sticholysin II (St II) is a highly hemolytic cytolysin isolated from the sea anemone Stichodactyla heliantus. The toxin hemolytic action takes place through the formation of channels that provoke an electrolyte unbalance leading to osmotic shock. The lytic event must involve the exchange of electrolytes and the entrance of water, leading to red blood cell disruption. These processes can occur through St II pores and/or the endogenous red blood cells transporters. In order to evaluate the contribution of these channels to water, anion and cation transport, we have measured the hemolysis and K+ efflux rates in the presence of several specific inhibitors. The results obtained in the presence of Hg, an AQP1 blocker, indicate that water transport through these channels is not essential for the occurrence of the lytic process induced by St II. The data also support a partial role of K+ and anion transporters. In particular, they are compatible with a preferential K+ efflux though the K(+)/Cl- co-transport as a response to the promoted swelling. Furthermore, they suggest that chloride influx, a process that can regulate both K+ efflux and lysis, is partially mediated by the endogenous cell transporters, in particular, band-3 anion exchange system being relevant at early stages of the lytic process.

Melanin-concentrating hormone inputs to the nucleus accumbens originate from distinct hypothalamic sources and are apposed to GABAergic and cholinergic cells in the Long-Evans rat brain.

Melanin-concentrating hormone [MCH] is a neuropeptide that modulates several behaviors, such as feeding and reward. Because the hedonic and rewarding features of a food also influence feeding behavior, the nucleus accumbens [Acb] has been highlighted as a key area integrating these roles. Functional data confirm that MCH acts on a subdivision of the Acb; however, considering the importance of finding anatomical and neurochemical data that correlate the previously demonstrated function of MCH, we delineated this investigation based on the following points: (1) Is there a pattern of innervation by MCH fibers regarding the subregions within the Acb? (2) Specifically, which hypothalamic nuclei synthesize MCH and innervate the Acb? (3) Finally, what are the neurochemical identities of the accumbal neurons innervated by MCH inputs? We examined the MCH immunoreactivity [MCH-ir] in the Acb in rat brains using the peroxidase technique. Additionally, after injecting retrograde neuronal tracer [Fluoro-Gold® - FG®] into subdivisions of the Acb [shell or core], we mapped single- or double-labeled cells. Moreover, using a double immunoperoxidase protocol, we investigated the MCH-ir fibers for gamma-aminobutyric acid [GABA]-ir and choline acetyltransferase [ChAT]-ir cells in the shell subdivision of the Acb [AcbSh]. We found that the MCH-ir fibers preferentially innervate the medial AcbSh, particularly the septal pole. This innervation originated from the incerto-hypothalamic area [IHy], internuclear area, lateral hypothalamic area, perifornical area, periventricular nucleus and posterior hypothalamus. Moreover, the IHy has the highest relationship between double/single retrogradely labeled cells [n=5.33±0.66/16±0.93, i.e. 33.33%] in the whole hypothalamus. Furthermore, our data suggest that MCH-ir fibers are in apposition to GABAergic and cholinergic cells in the AcbSh. Therefore, we provide anatomical support to the ongoing functional studies investigating the relation among the hypothalamus, MCH transmission into the Acb and the involvement of known neuronal phenotypes within the AcbSh.

Activity coefficients of the electrolyte and the amino acid in water + NaNO(3) + glycine and water + NaCl + DL-methionine systems at 298.15 K.

The activity coefficients at 298.15 K of glycine in water + NaNO(3) + glycine system and dl-methionine in water + NaCl + dl-methionine system are reported. The measurements were performed in an electrochemical cell with two ion selective electrodes, a cation and an anion ion selective electrode, each versus a double junction reference electrode. The concentrations of the electrolytes and the amino acids studied covered up to 1.0 molality electrolyte, 2.4 molality glycine and 0.2 molality dl-methionine. The results of the activity coefficients of glycine are compared with the activity coefficients of glycine in water + NaCl + glycine and water + KCl + glycine systems, obtained from the previous studies. The results show that the nature of both the cation and the anion of an electrolyte have significant effects on the activity coefficient of glycine in aqueous electrolyte solutions. The results also show that there are attractive interactions between the molecules of glycine and NaNO(3) and repulsive interactions between the molecules of dl-methionine and NaCl.

Properties of St I and St II, two isotoxins isolated from Stichodactyla helianthus: a comparison.

Sticholysins I and II are two highly hemolytic polypeptides purified from the Caribbean Sea anemone Stichodactyla helianthus. Their high sequence homology (93%) indicates that they correspond to isoforms of the same hemolysin. The spectroscopic measurements show a close similarity in the secondary structure content, conformation and stability of both toxins. Exposure of the toxins to high pHs (>11), a free radical source (AAPH), urea or temperature produce permanent changes in the toxin that lead to a significant loss of HA. It is significant to note that this loss of hemolytic activity occurs when other indicators, probably with the only exception of near-UV CD spectra, barely detect changes in the protein structure. This emphasizes the sensitivity of the protein function to changes in the macromolecule conformation. The most noticeable difference between both toxins is the considerably higher activity of St II, both measured in terms of erythrocyte internal K(+) exit or hemolysis; which is related to enthalpic factors. This difference is not due to an incomplete association of St I to the membrane. We consider then that the different pore forming capacity of both toxins in erythrocytes can be explained in terms of the difference in charge of the N-terminal fragment, than can considerably reduce the St I insertion rate in the membrane probably due to the negatively charged outer leaflet of the red blood cell, without a significant reduction of its capacity to bind to the cell membrane. This electrostatic effect, together with a slightly more relaxed structure in St II, could explain the higher pore forming capacity of St II in the red blood cell membrane.

The role of ionic strength on the enhancement of the hemolytic activity of sticholysin I, a cytolysin from Stichodactyla helianthus.

Sticholysin I (St I) is a potent cytolytic polypeptide purified from the Caribbean sea anemone Stichodactyla helianthus. The hemolytic activity of sticholysin is potentiated by its preincubation at high ionic strengths. In the present work the mechanism of the potentiating action of the medium ionic strength on the toxin hemolytic capacity is investigated. It is suggested that preincubation with high saline concentration induces a transition of St I to a more relaxed conformation that facilitates the lytic process.

Modification of sticholysin II hemolytic activity by free radicals.

Sticholysin II is a highly hemolytic toxin present in the caribbean sea anemone Stichodactyla helianthus. Pre-incubation of St II with 2,2'-azobis(2-amidinopropane), a source of peroxyl radicals in air saturated solution, readily reduces its hemolytic activity. Analysis of the amino acids present in the protein after its modification shows that only tryptophan groups are significantly modified by the free radicals. According to this, the loss of hemolytic activity correlates with the loss of the protein intrinsic fluorescence. The results indicate that, at high toxin concentrations, nearly a tryptophan residue and 0.2 toxin molecules are inactivated by each radical introduced into the system. Association of St II to multilamellar liposomes (egg yolk phosphatidyl choline:sphingomyelin 1:1) increases the toxin intrinsic fluorescence, indicating a more hydrophobic average environment of the five tryptophan groups of the protein. In agreement with this, incorporation of St II to the liposomes reduces the rate of fluorescence loss during its modification by free radicals, particularly at long incubation times. These results are explained in terms of two populations of tryptophans that are quenched at different rates by acrylamide and whose rates of inactivation by free radicals are also different.

Effect of pH on the conformation, interaction with membranes and hemolytic activity of sticholysin II, a pore forming cytolysin from the sea anemone Stichodactyla helianthus.

Sticholysin II (St II) is a pore forming cytolysin obtained from the sea anemone Stichodactyla helianthus. Incubation of diluted St II solutions at different pHs (ranging from 2.0 to 12) slightly changes the secondary structure of the protein. These changes are particularly manifested at high pH. Similarly, the intrinsic fluorescence of the protein indicates a progressive opening of the protein structure when the pH increases from acidic (2.0) to basic (12). These modifications are only partially reversible and do not produce any significant increase in the small capacity of the protein to bind hydrophobic dyes (ANS or Prodan). Experiments carried out with model membranes show a reduced capacity of binding to egg phosphatidyl choline:sphingomyelin (1:1) liposomes both at low (2.3) and high (11.5) pH. Preincubation of the protein in the 2. 5-9.0 pH range does not modify its hemolytic activity, measured in human red blood cells at pH 7.4. On the other hand, preincubation at pH 11.5 drastically reduces the hemolytic activity of the toxin. This strong reduction takes place without measurable modification of the toxin ability to be adsorbed to the red blood cell surface. This indicates that preincubation at high pH irreversibly reduces the capacity of the toxin to form pores without a significant decrease in its binding capacity. The present results suggest that at pH > or = 10 St II experiences irreversible conformational changes that notably reduce its biological activity. This reduced biological activity is associated with a partial defolding of the protein, which seems to contradict what is expected in terms of a molten globule formalism.