Mechanically primed cells transfer memory to fibrous matrices for invasion across environments of distinct stiffness and dimensionality.

Cells sense and migrate across mechanically dissimilar environments throughout development and disease progression. However, it remains unclear whether mechanical memory of past environments empowers cells to navigate new, three-dimensional extracellular matrices. Here, we show that cells previously primed on stiff, compared with soft, matrices generate a higher level of forces to remodel collagen fibers and promote invasion. This priming advantage persists in dense or stiffened collagen. We explain this memory-dependent, cross-environment cell invasion through a lattice-based model wherein stiff-primed cellular forces remodel collagen and minimize energy required for future cell invasion. According to our model, cells transfer their mechanical memory to the matrix via collagen alignment and tension, and this remodeled matrix informs future cell invasion. Thus, memory-laden cells overcome mechanosensing of softer or challenging future environments via a cell-matrix transfer of memory. Consistent with model predictions, depletion of yes-associated protein destabilizes the cellular memory required for collagen remodeling before invasion. We release tension in collagen fibers via laser ablation and disable fiber remodeling by lysyl-oxidase inhibition, both of which disrupt cell-to-matrix transfer of memory and hamper cross-environment invasion. These results have implications for cancer, fibrosis, and aging, where a potential cell-to-matrix transfer of mechanical memory of cells may generate a prolonged cellular response.

Nucleoli in epithelial cell collectives respond to tumorigenic, spatial, and mechanical cues.

Cancer cells are known to have larger nucleoli, consistent with their higher transcriptional and translational demands. Meanwhile, on stiff extracellular matrix, normal epithelial cells can exhibit genomic and proteomic mechanoactivation toward tumorigenic transformations, such as epithelial-mesenchymal transition and enhanced migration. However, while nucleolar bodies regulate the protein synthesis required for mechanosensation, it remains unknown whether mechanical and spatial extracellular cues can in turn alter nucleoli. Here, we culture mammary epithelial cell sheets on matrices of varying stiffness and show that cancer cells have more nucleoli, with nucleoli occupying larger areas compared with normal cells. By contrast, within normal epithelial sheets, stiffer matrices and leader positioning of cells induce larger nucleolar areas and more nucleolar bodies over time. The observed leader-follower nucleolar differences stem from distinct rates of cell cycle progression. In the nucleoplasm, leader cells on stiffer matrices exhibit higher heterochromatin marker expression and DNA compaction around nucleolar bodies. Overall, our findings advance the emerging framework of cellular mechanobiology in which mechanical cues from the extracellular matrix transmit into the nucleoplasm to alter nucleolar composition, potentially resulting in mechanosensitive ribosomal biogenesis. Ultimately, this proposed mechanosensitivity of nucleoli and associated protein synthesis could have wide implications in disease, development, and regeneration.

Undiagnosed Sturge-Weber Syndrome as a Differential Diagnosis of Seizures and Deep Cerebral Venous System Dilation: A Case Report.

Sturge-Weber syndrome (SWS) is a capillary-venous malformation affecting the brain, the eye, and the adjacent trigeminal dermatomes of the skin. This illness is usually diagnosed during the first years of life. If left undiagnosed (and consequently untreated), the condition could develop into severe refractory seizures, ischemic strokes, visual loss, and early cognitive impairment. We report a case of a 23-year-old female patient with a port-wine facial stain, presenting her first convulsive episode in adulthood, associated with a moderate dilation of the deep venous system in the angiography, which raised the diagnostic of Sturge-Weber syndrome.

Percutaneous closure of ostium secundum atrial septal defect using left internal jugular vein access in a child with situs inversus and absence of inferior caval vein.

Femoral vein access is the first choice for percutaneous atrial septal defect closure, and when it cannot be used due to anatomic reasons, the alternative sites should be considered, frequently increasing the complexity of the procedure. Here we report the case of a 3-year-old boy, with situs inversus and dextrocardia, electively referred for percutaneous closure of an ostium secundum atrial septal defect. During the procedure, agenesis of the infra-hepatic segment of the inferior caval vein was diagnosed, and no double inferior caval vein or right superior caval vein were identified by ultrasound or angiography. Therefore, we opted to perform the procedure through the left internal jugular vein, with fluoroscopy and transesophageal echocardiographic guidance. Catheters were navigated through a hydrophilic guidewire, and a Stiff guidewire was positioned in the left ventricle for better support. An Amplatzer septa occluder 19 was successfully deployed without major difficulties and the patient was discharged after 24 hours in good clinical condition. Percutaneous atrial septal defect closure through alternative access sites, especially in the presence of situs inversus, may pose significant challenges to the interventional team. In this case, the left internal jugular vein has shown to be a feasible option, allowing the navigation and manipulation of devices without complications. Provided the expertise of the interventional team, and awareness of the risks involved, alternative access sites can be successfully used for paediatric structural interventions.

Predicting frequency distribution and influence of sociodemographic and behavioral risk factors of Schistosoma mansoni infection and analysis of co-infection with intestinal parasites.

Geospatial analysis was used to study the epidemiology of Schistosoma mansoni, intestinal parasites and co-infections in an area (Ilha das Flores) in Sergipe, Brazil. We collected individually georeferenced sociodemographic, behavioral and parasitological data from 500 subjects, analyzed them by conventional statistics, and produced risk maps by Kernel estimation. The prevalence rates found were: S. mansoni (24.0%), Trichuris trichiura (54.8%), Ascaris lumbricoides (49.2%), Hookworm (17.6%) and Entamoeba histolytica (7.0%). Only 59/500 (11.8%) individuals did not present any of these infections, whereas 279/500 (55.8%) were simultaneously infected by three or more parasites. We observed associations between S. mansoni infection and various variables such as male gender, being rice farmer or fisherman, low educational level, low income, water contact and drinking untreated water. The Kernel estimator indicated that high-risk areas coincide with the poorest regions of the villages as well as with the part of the villages without an adequate sewage system. We also noted associations between both A. lumbricoides and hookworm infections with low education and low income. A. lumbricoides infection and T. trichiura infection were both associated with drinking untreated water and residential open-air sewage. These findings call for an integrated approach to effectively control multiple parasitic infections.

Evaporative heat loss in Bos taurus: do different cattle breeds cope with heat stress in the same way?

The aim of this study was to compare two Portuguese (Alentejana and Mertolenga) and two exotic (Frisian and Limousine) cattle breeds in terms of the relationship between the increase in ambient temperature and the responses of the evaporative heat loss pathways and the effects on homeothermy. In the experiment, six heifers of the Alentejana, Frisian, and Mertolenga breeds and four heifers of the Limousine breed were used. The animals were placed in four temperature levels, the first one under thermoneutral conditions and the other ones with increase levels of thermal stress. When submitted to severe heat stress, the Frisian developed high thermal tachypnea (125 mov/min) and moderate sweating rates (117 gm(-2) h(-1)), which did not prevent an increase in the rectal temperature (from 38.4 °C to 40.0 °C). Moderate increases in rectal temperature were observed in the Alentejana (from 38.8 °C to 39.4 °C) and Limousine (from 38.6 °C to 39.4 °C), especially in the period of highest heat stress. The Limousine showed moderate levels of tachypnea (101 mov/min) while showing the lowest sweating rates. The Alentejana showed significant increases in sweating rate (156 gm(-2)h(-1)) that played a major role in homeothermy. The Mertolenga showed a superior stability of body temperature, even in the period of highest heat stress (from 38.5 °C to 39.1 °C). Uncommonly, the maintenance of homeothermy during moderate heat stress was achieved primarily by intense tachypnea (122 mov/min). The sweating rate remained abnormally low under conditions of moderate heat stress, rising significantly (110 gm(-2)h(-1)) without evidence of stabilization, only when tendency for heat storage occurred. This unusual response of the evaporative heat loss pathways infers a different thermoregulatory strategy, suggesting a different adaptation to semi-arid environment and strong association with water metabolism.

A ß-mercaptoethanol-modified enzyme-linked immunosorbent assay for diagnosis of canine visceral leishmaniasis.

Two immunoglobulin G enzyme-linked immunosorbent assay (ELISA) versions using whole promastigotes of Leishmania infantum (syn. Leishmania chagasi) treated either with ß-mercaptoethanol (ß-ME-ELISA) or trypsin (TRYP-ELISA) as antigens were developed for the diagnosis of canine visceral leishmaniasis (CVL). By comparison with the direct agglutination test (DAT; 100%, 31/31; 95% confidence interval [CI]: 86.3-100%), slightly lower sensitivity was demonstrated for the newly developed ß-ME-ELISA (93.5%, 29/31; 95% CI: 77.2-98.9%). Sensitivity was higher for ß-ME-ELISA compared with TRYP-ELISA (87.1%, 27/31; 95% CI: 69.2-95.8%) in serum samples from dogs with CVL. When tested with sera from 37 healthy dogs and from 45 dogs with clinical conditions other than CVL, a specificity of 97.6% (80/82; 95% CI: 90.1-99.6%) was estimated for ß-ME-ELISA as compared to 100% (82/82; 95% CI: 94.4-100%) and 95.1% (78/82; 95% CI: 87.3-98.4%) for DAT and TRYP-ELISA, respectively. Observed agreement was 94.0% (95% CI: 88.7-97.1%) between DAT and ß-ME-ELISA (κ = 0.879; 95% CI: 0.803-0.956) and 87.4% (95% CI: 80.8-92.1%) between DAT and TRYP-ELISA (κ = 0.743; 95% CI: 0.636-0.851). Current results advocate application of the new ß-ME-ELISA for diagnosis of CVL at the laboratory level and confirmation of results obtained with the DAT in field studies.

Proteomics characterization of mouse kidney peroxisomes by tandem mass spectrometry and protein correlation profiling.

The peroxisome represents a ubiquitous single membrane-bound key organelle that executes various metabolic pathways such as fatty acid degradation by alpha- and beta-oxidation, ether-phospholipid biosynthesis, metabolism of reactive oxygen species, and detoxification of glyoxylate in mammals. To fulfil this vast array of metabolic functions, peroxisomes accommodate approximately 50 different enzymes at least as identified until now. Interest in peroxisomes has been fueled by the discovery of a group of genetic diseases in humans, which are caused by either a defect in peroxisome biogenesis or the deficient activity of a distinct peroxisomal enzyme or transporter. Although this research has greatly improved our understanding of peroxisomes and their role in mammalian metabolism, deeper insight into biochemistry and functions of peroxisomes is required to expand our knowledge of this low abundance but vital organelle. In this work, we used classical subcellular fractionation in combination with MS-based proteomics methodologies to characterize the proteome of mouse kidney peroxisomes. We could identify virtually all known components involved in peroxisomal metabolism and biogenesis. Moreover through protein localization studies by using a quantitative MS screen combined with statistical analyses, we identified 15 new peroxisomal candidates. Of these, we further investigated five candidates by immunocytochemistry, which confirmed their localization in peroxisomes. As a result of this joint effort, we believe to have compiled the so far most comprehensive protein catalogue of mammalian peroxisomes.

Cholesterol-lowering effects of dietary blue lupin (Lupinus angustifolius L.) in intact and ileorectal anastomosed pigs.

The present study was undertaken to investigate the effect of cholesterol-enriched casein (CAS) and blue lupin seed (BL) diets on the cholesterol metabolism of intact (INT) and ileorectal anastomosed (IRA) pigs. For 3 weeks, four groups of six pigs were allocated to the treatments (CAS-INT, CAS-IRA, BL-INT, and BL-IRA). Diet-induced hypercholesterolemia was inhibited by the BL through a substantial decrease in plasma LDL-cholesterol. The BL also reduced liver esterified and total cholesterol, increased hepatic LDL receptor synthesis and HMG-CoA reductase activity, and stimulated intestinal bile acid reabsorption. The neutral sterol output was higher in BL- than in CAS-fed pigs. The bile acid output was lower in IRA than in INT pigs. Surgery also prevented steroid microbial transformation, but it did not influence plasma cholesterol levels. These results suggest that the hypocholesterolemic effect of the BL, compared with the CAS, is attributable to impaired intestinal cholesterol absorption, probably involving increased bile acid reabsorption and higher contents of dietary phytosterols, both factors that reduce the micellar solubilization of cholesterol. Furthermore, according to our data, the contribution of the large intestine to cholesterol metabolism is very weak.

Dietary raw peas (Pisum sativum L.) reduce plasma total and LDL cholesterol and hepatic esterified cholesterol in intact and ileorectal anastomosed pigs fed cholesterol-rich diets.

Previous studies demonstrated the cholesterol-lowering effect of dietary legumes (mainly soybeans) in animals and humans, but the mechanisms by which they exert this effect are not completely understood. The contribution of the hindgut to this hypocholesterolemic effect is also not well documented. The present work was undertaken to investigate the effect of cholesterol-enriched (2.8 g/kg) casein (C) and raw pea seed (RP) diets on the cholesterol metabolism of intact (I) and ileorectal anastomosed (IRA) growing pigs. Four groups of 6 pigs were allocated to the treatments (C-I, C-IRA, RP-I, and RP-IRA pigs) for 3 wk. Plasma total cholesterol was lowered by the RP diet through a significant decrease in LDL cholesterol. The RP diet also decreased the hepatic concentration of esterified cholesterol and increased 3-hydroxy-3-methylglutaryl CoA reductase activity and LDL receptor synthesis. The biliary total cholesterol and bile acid concentrations were greater in RP- than in C-fed pigs. In addition, fecal bile acid output was higher in RP-fed pigs. The cecum-colon by-pass inhibited cholesterol and beta-sitosterol microbial transformation, lowered the bile acid output, and increased the primary to secondary bile acid output ratio, but its influence on cholesterolemia was negligible. These results suggest a hypocholesterolemic effect of the raw pea diet probably due to increased fecal bile acid output and an increased biliary bile acid concentration.

Effects of ileo-rectal anastomosis on cholesterol metabolism in pigs fed either casein or extruded soya beans.

The importance of legume proteins in cholesterol metabolism has been recognised, but the hindgut contribution is still unclear. The present work was undertaken to address the role of the caecum-colon in cholesterol metabolism in intact (I) and ileo-rectal anastomosed (IRA) pigs fed with casein or extruded soyabean (ES) diets. Four groups of six growing pigs were assigned to the treatments (casein-I, casein-IRA, ES-I, ES-IRA) for 3 weeks. Plasma total cholesterol, LDL- and HDL-cholesterol were not modified by surgery or diet. In the liver, the ES diet significantly depressed non-esterified, esterified and total cholesterol. The treatments did not affect hepatic 3-hydroxy-3-methylglutaryl CoA reductase, cholesterol 7alpha-hydroxylase or sterol 27-hydroxylase activities. In the gallbladder bile of ES-fed pigs, total cholesterol was depressed while total bile acid concentration was increased. IRA and the ES diet markedly decreased the biliary bile acid microbial metabolites (namely hyodeoxycholic acid) and increased the primary bile acids (mainly hyocholic acid). The concentration of bile hydrophobic acids was decreased only by the ES diet. Faecal neutral sterol output was increased in ES-fed pigs, but the bile acid and the sum of neutral and acidic steroid outputs were not. Microbial transformation of neutral and acidic steroids was markedly reduced by IRA, especially in the ES-fed pigs. Thus, surgery and ES modulated the steroid profile but the caecum-colon did not seem to play a crucial role in determining cholesterolaemia in pigs.

Estudo da matrix extra-celular da próstata durante o período fetal humano / Study of extracellular matrix of the prostate during human fetal period

Objetivo: Analisar a ontogênese dos diferentes componentes da matriz extra-celular na próstata, divididas em quatro grupos de três próstatas provenientes de fetos com as seguintes idades: 10, 18 21 e 25 semanas pós-concepçäo (SPC). Foi feito um estudo do sistema elástico e das fibras colágenas. O estudo histoquímico das fibras colágenas foi feito com o tricrômico de Gomori e com o método do Sirius Red; foram também utilizados anticorpos contra os colágenos tipo-I e tipo-III. Para a análise histoquímica o anticorpo contra elastina humana. Resultados: Colágeno: No início do período gestacional (10 SPC) observamos uma grande quantidade do colágeno tipo-I e tipo-III. Com o desenvolvimento fetal (18 e 25 SPC) ocorreu um aumento progressivo na quantidade de colágeno tipo-I com uma diminuiçäo concomitante do colágeno tipo-III. Na regiäo periférica da próstata e próximo aos ductos ejaculatórios, as fibras colágenas säo raras quando comparadas com as outras regiöes da próstata, sendo esse fato observado durante todo o período fetal. Fibras elásticas: Com 10 SPC foi observada pequena concentraçäo de fibras elásticas, localizadas principalmente na regiäo ventral da próstata. A concentraçäo de fibras elásticas aumentam com a idade gestacional, estando presente em todas as regiöes prostáticas, especialmente ao redor dos ácinos e na regiäo uretral. Conclusöes: Com o desenvolvimento fetal ocorre um aumento nas concentraçöes de colágeno tipo-I e elastina com um simultâneo decréscimo no colágeno tipo-III