457 research outputs found
Tissue engineering and regenerative medicine research - how can it contribute to fight future pandemics?
Understanding the pathogenesis of viral infection is of paramount importance for the development of better therapies. In the particular case of COVID-19, the mechanism of infection is highly complex and involves a critical cascade of events, which can lead to the death of the patient. Intense research is currently being performed to gain mechanistic insights about the virus etiology and to evaluate new therapeutic approaches. The development of point-of-care diagnostic tools, predictive drug screening platforms, and biomimetic models of the disease could play a key role in understanding the cellular and molecular mechanism of viral infection and its response to drugs. In this regard, specific tissue engineering and regenerative medicine approaches, such as microfluidics and organ-on-a-chip technologies, as well as bioprinted in vitro disease models, could be used to develop a technological platform to fight COVID-19,
and other virus pandemics yet to come. Herein, we briefly discuss about how such approaches can contribute to address current and future viral pandemics by highlighting recent successful examples.D. Caballero acknowledges the financial support from the Portuguese Foundation for Science and Technology under the program CEEC Individual 2017 (CEECIND/00352/2017) and the project 2MATCH (02/SAICT/2017 - nº 028070) funded by the Programa Operacional Regional do Norte supported by FEDER. M.
Carvalho would like to acknowledge IET Harvey Research Prize 2017. The authors
also acknowledge the financial support from the EU Framework Programme for Research and Innovation Horizon 2020 on Forefront Research in 3D Disease Cancer
Models as in vitro Screening Technologies (FoReCaST- no. 668983), the Portuguese
Foundation for Science and Technology (FCT) distinction attributed to J. M. Oliveira (IF/00423/2012, IF/01285/2015) and FCT, Fundo Europeu de Desenvolvimento Regional (FEDER) and Programa Operacional Competitividade e Internacionalização (POCI) for funding the projects B-Liver (PTDC/EMD-EMD/29139/2017),
Hierarchitech (M-ERA-NET/0001/2014) and 3BioMeD (JICAM/0001/2017)
Early impact of abdominal compartment syndrome on liver, kidney and lung damage in a rodent model
Background: Abdominal compartment syndrome (ACS) sometimes occurs in critically ill patients following
damage control surgery. The purpose of the present study was to develop a model of ACS and to evaluate its
pathologic impact on liver, kidney, and lung morphology.
Methods: Twenty Wistar rats (mass 300\u2013350 g) were randomly divided into four groups: 1) intra-abdominal
hypertension (IAH): a laparotomy was performed and the abdomen packed with cotton until an intra-abdominal
pressure (IAP) of 15 mm Hg was reached; 2) hypovolemia (HYPO): blood was withdrawn until a mean arterial
pressure ~60 mm Hg was reached; 3) IAH + HYPO (to resemble clinical ACS); and 4) sham surgery. After 3
hours of protective mechanical ventilation, the animals were euthanized and the liver, kidney and lungs removed
to examine the degree of tissue damage.
Results: IAH resulted in the following: oedema and neutrophil infiltration in the kidney; necrosis, congestion,
and microsteatosis in the liver; and alveolar collapse, haemorrhage, interstitial oedema, and neutrophil
infiltration in the lungs. Furthermore, IAH was associated with greater cell apoptosis in the kidney, liver and
lungs compared to sham surgery. HYPO led to oedema and neutrophil infiltration in the kidney. The
combination of IAH and HYPO resulted in all the aforementioned changes in lung, kidney and liver tissue, as
well as exacerbation of the inflammatory process in the kidney and liver and kidney cell necrosis and apoptosis.
Conclusions: Intra-abdominal hypertension by itself is associated with kidney, liver and lung damage; when
combined with hypovolemia, it leads to further impairment and organ damage
Intravenous glutamine decreases lung and distal organ injury in an experimental model of abdominal sepsis
Introduction The protective effect of glutamine, as a pharmacological agent against lung injury, has been reported in experimental sepsis; however, its efficacy at improving oxygenation and lung mechanics, attenuating diaphragm and distal organ injury has to be better elucidated. In the present study, we tested the hypothesis that a single early intravenous dose of glutamine was associated not only with the improvement of lung morpho-function, but also the reduction of the inflammatory process and epithelial cell apoptosis in kidney, liver, and intestine villi. Methods Seventy-two Wistar rats were randomly assigned into four groups. Sepsis was induced by cecal ligation and puncture surgery (CLP), while a sham operated group was used as control (C). One hour after surgery, C and CLP groups were further randomized into subgroups receiving intravenous saline (1 ml, SAL) or glutamine (0.75 g/kg, Gln). At 48 hours, animals were anesthetized, and the following parameters were measured: arterial oxygenation, pulmonary mechanics, and diaphragm, lung, kidney, liver, and small intestine villi histology. At 18 and 48 hours, Cytokine-Induced Neutrophil Chemoattractant (CINC)-1, interleukin (IL)-6 and 10 were quantified in bronchoalveolar and peritoneal lavage fluids (BALF and PLF, respectively). Results CLP induced: a) deterioration of lung mechanics and gas exchange; b) ultrastructural changes of lung parenchyma and diaphragm; and c) lung and distal organ epithelial cell apoptosis. Glutamine improved survival rate, oxygenation and lung mechanics, minimized pulmonary and diaphragmatic changes, attenuating lung and distal organ epithelial cell apoptosis. Glutamine increased IL-10 in peritoneal lavage fluid at 18 hours and bronchoalveolar lavage fluid at 48 hours, but decreased CINC-1 and IL-6 in BALF and PLF only at 18 hours. Conclusions In an experimental model of abdominal sepsis, a single intravenous dose of glutamine administered after sepsis induction may modulate the inflammatory process reducing not only the risk of lung injury, but also distal organ impairment. These results suggest that intravenous glutamine may be a potentially beneficial therapy for abdominal sepsis.Centres of Excellence Program (PRONEX-FAPERJ)Brazilian Council for Scientific and Technological Development (CNPq)Carlos Chagas FilhoRio de Janeiro State Research Supporting Foundation (FAPERJ)Sao Paulo State Research Supporting Foundation (FAPESP
Diagnóstico precoce de neoplasia endócrina múltipla tipo 2B: um desafio para os médicos
BACKGROUND: The hereditary form of medullary thyroid carcinoma may occur isolated as a familial medullary thyroid carcinoma (FMTC) or as part of Multiple Endocrine Neoplasia 2A (MEN2A) and 2B (MEN2B). MEN2B is a rare syndrome, its phenotype may usually, but not always, be noted by the physician. In the infant none of the MEN2B characteristics are present, except by early gastrointestinal dysfunction caused by intestinal neuromas. When available, genetic analysis confirms the diagnosis and guides pre-operative evaluation and extent of surgery. Here we report four cases of MEN2B in which the late diagnosis had a significant impact in clinical evolution and, potentially, in overall survival. CASE REPORT: We report four cases, 2 men and 2 women, with differences in their phenotypes and with a late diagnosis. The first case has a history of severe gastrointestinal obstruction requiring a surgery intervention two days after his birth. The second told had nodules in the oral mucosa and constipation since childhood. The third case referred a history of constipation from birth until 5 months of life. The fourth has had a history of chronic constipation since childhood. DISCUSSION: New concepts have emerged since the RET oncogene was identified in 1993 as the responsible gene for hereditary medullary thyroid carcinoma. The majority of MEN2B individuals have M918T mutation in the exon 16 of RET, with a few cases having a mutation A883F or the association of V804M with E805K, Y806C or S904C mutations. The consensus classifies the RET mutation in codon 918 as of highest risk and recommends total thyroidectomy and central lymph node dissection until 6 months after birth. A fast and precise diagnosis is essential to reach these goals. The identification of early manifestations such as intestinal ganglioneuromatosis and oral mucosal neuromas should prompt the physician to initiate an investigation for multiple endocrine neoplasia type 2B. CONCLUSION: The diagnosis of MEN2B is very important to allow appropriate investigation of associated diseases and to allow counseling and appropriate screening of relatives for a RET mutation. Even patients with MEN2B, which often have typical physical features, may not be properly recognized and be followed as a sporadic case. Based on this, all suspicious cases of multiple endocrine neoplasia should undergo a molecular genetic test.A forma hereditária do carcinoma medular da tiróide pode ocorrer de modo isolado, o carcinoma medular da tiróide familiar (FMTC), ou como parte das neoplasias endócrinas múltiplas tipo 2A (MEN2A) e 2B (MEN2B). MEN2B é uma sÃndrome rara e seu fenótipo é usualmente, mas nem sempre, notado pelo médico. Na infância, nenhuma das caracterÃsticas de MEN2B estão presentes, exceto pela disfunção gastrintestinal precoce, causada pelos neuromas intestinais. Quando disponÃvel, a análise genética confirma o diagnóstico e orienta a avaliação pré-operatória e extensão da cirurgia. Neste artigo, apresentamos quatro casos de MEN2B, nos quais o diagnóstico tardio teve impacto significativo na evolução clÃnica e, potencialmente, na mortalidade em geral. APRESENTAÇÃO DOS CASOS: Apresentamos quatro casos, dois homens e duas mulheres, com diferenças em seus fenotipos e com diagnóstico tardio. O primeiro caso tem história de obstrução gastrintestinal importante em que foi necessária cirurgia dois dias após o nascimento. O segundo paciente apresentava nódulos na mucosa oral e constipação desde a infância. O terceiro referia história de constipação desde o nascimento até 5 meses de idade. O quarto tinha história de constipação intestinal desde a infância. DISCUSSÃO: Novos conceitos emergiram desde que o oncogene RET foi identificado, em 1993, como o gene responsável pelo carcinoma medular da tiróide hereditário. A maioria dos indivÃduos apresenta a mutação M918T no éxon 16 do RET, enquanto poucos casos apresentam a mutação A883F ou a associação de V804M com E805K, Y806C ou S904C. O consenso recomenda a tiroidectomia total com dissecção dos linfonodos no compartimento central até os 6 meses após o nascimento. O diagnóstico rápido e preciso é essencial para o atingir os objetivos. CONCLUSÃO: O diagnóstico precoce de MEN2B é muito importante para propiciar a investigação apropriada de doenças associadas e para permitir aconselhamento e rastreamento dos parentes para uma mutação do RET. Pacientes com MEN2B, que apresentam frequentemente achados tÃpicos ao exame fÃsico, podem não ser reconhecidos e seguidos como casos esporádicos. Por causa disso, todos os casos de neoplasia endócrina múltipla devem ser avaliados pelo teste genético para mutações do RET.Federal University of São Paulo Department of Medicine Division of EndocrinologyFleury-Medicina e SaúdeUNIFESP, Department of Medicine Division of EndocrinologySciEL
Perillyl alcohol in Solid Lipid Nanoparticles (SLN-PA): Cytotoxicity and antitumor potential in sarcoma 180 mice model
Cancer is a group of diseases characterized by the uncontrolled growth of cells. These cells invade organs and tissues by extension or direct dissemination and can spread to other regions of the body.
Nanomedicine offers many possibilities to prevent the spread of cancer tissue and help cure the disease.
In this work, solid lipid nanoparticles (SLN) were used to encapsulate perillyl alcohol (PA), a volatile
monoterpene with proven anticancer activity. Encapsulation of PA into SLN (SLN-PA) is expected to
promote controlled release, increase PA bioavailability, and impair the volatility of the monoterpene.
SLN-PA prepared by high-shear homogenization showed average particle diameter around 254 nm,
polydispersity index ~ 0.35, zeta potential ~ -14.7 mV, and encapsulation efficiency 84.6%. Scanning
electron microscope analysis revealed a decrease in crystallinity, suggesting the encapsulation of PA in
the SLN, confirming the spherical shape and the loading of the monoterpene in the SLN. In vitro cytotoxicity
assays against murine fibroblasts (L929) showed that SLN-PA in both treated doses did not
induce any cytotoxicity on non-tumoral cells. In vivo antitumor effect of the SLN-PA was evaluated in
sarcoma 180-transplanted mice. The in vivo results demonstrated a significant tumor inhibition rate of
51.76 and 54.49% via intraperitoneal application of SLN-PA at doses of 100 and 200 mg/kg/day (p <
0.05), respective when compared to the negative control (dimethyl sulfoxide). Adverse side effects of
SLN-PA were not noticed in the liver, the kidney, or spleen tissue. The developed SLN-PA can be
considered as a safe approach for site-specific antitumor effect in vivo, reinterpreting new nanoparticles-
based cancer therapy.This work was supported by the Banco do Nordeste (grant FUNDECI/2016.0015), Conselho Nacional
de Desenvolvimento CientÃfico e Tecnológico (CNPq), Fundação de Apoio à Pesquisa e à Inovação
Tecnológica do Estado de Sergipe (Fapitec) and Coordenação de Aperfeiçoamento de Pessoal de NÃvel
Superior (CAPES). Eliana B. Souto would like to acknowledge the Portuguese Science and Technology
Foundation (FCT/MCT) and from European Funds (PRODER/COMPETE) for the project
UIDB/04469/2020 (strategic fund), co-financed by FEDER, under the Partnership Agreement PT2020.info:eu-repo/semantics/publishedVersio
Atherosclerosis and Bone Loss in Humans–Results From Deceased Donors and From Patients Submitted to Carotid Endarterectomy
Funding: We wish to thank all the collaborators (administrative staff, nurses, etc.) of the surgery block, as well as the doctors of the vascular surgery and transplantation departments of the Hospital of Santa Maria for the availability and assistance in the collection of the samples. We also thank Sociedade Portuguesa de Reumatologia for funding with two fellowships: Fundo de Apoio à Investigação 2014 and SPR/MSD 2015. DC-F received funding from a PhD grant from Fundação para a Ciência e a Tecnologia (SFRH/BD/80940/2011).Background and Aims: Atherosclerosis and osteoporosis share common risk factors, as well as inflammatory mechanisms. Our aim was to understand how atherosclerotic lesions are related with disturbances in bone. Methods: Gene expression of pro-inflammatory and bone metabolism related proteins (IL-1β, IL-6, IL-17A, TNF, RANKL, OPG, COL1, CTSK, OCL, TRAP, CBFA1, DKK1, SOST, ADIPOQ, and ADIPOR1) were analyzed in arteries and bones from 45 deceased donors and adipose tissue was used as control. Additionally, in 139 patients with advanced atherosclerosis submitted to carotid endarterectomy we compared calcium content (Alizarin red) and plaque inflammatory scores (CD3+, CD68+, and adiponectin) of patients with normal bone mineral density (BMD) with those with low BMD and explored the associations between gene expression in atherosclerotic plaques and BMD. Serum levels of pro-inflammatory and bone related proteins were measured both in donors and patients. Associations were investigated by the Pearson or Spearman correlation tests, and multivariate regression analyzes were performed when justified. Results: Gene expression of bone remodeling and pro-inflammatory proteins correlated positively in bone and aorta, independently of age and sex of donors, but not in adipose tissue. The expression of bone formation genes was significantly higher in atheroma plaques from endarterectomized patients with normal vs. low BMD as well as inflammatory CD68+ scores, regardless of patients' age and sex, but not of body mass index. No relationship was observed between serum levels and gene expression levels of pro-inflammatory or bone remodeling proteins. Conclusions: Our results suggest that the relationship between bones and vessels in the context of atherosclerotic disease and osteoporosis may rely on the intrinsic connection between the tissues involved, independently of disease stage. Serum measurements of pro-inflammatory and bone-remodeling proteins do not accurately translate tissue pathologic processes.publishersversionpublishe
Recommended from our members
The effect of fluoride on the structure, function, and proteome of intestinal epithelia.
Fluoride exposure is widespread, with drinking water commonly containing natural and artificially added sources of the ion. Ingested fluoride undergoes absorption across the gastric and intestinal epithelia. Previous studies have reported adverse gastrointestinal effects with high levels of fluoride exposure. Here, we examined the effects of fluoride on the transepithelial ion transport and resistance of three intestinal epithelia. We used the Caco-2 cell line as a model of human intestinal epithelium, and rat and mouse colonic epithelia for purposes of comparison. Fluoride caused a concentration-dependent decline in forskolin-induced Cl- secretion and transepithelial resistance of Caco-2 cell monolayers, with an IC50 for fluoride of about 3 mM for both parameters. In the presence of 5 mM fluoride, transepithelial resistance fell exponentially with time, with a t1/2 of about 7 hours. Subsequent imaging by immunofluorescence and scanning electron microscopy showed structural abnormalities in Caco-2 cell monolayers exposed to fluoride. The Young's modulus of the epithelium was not affected by fluoride, although proteomic analysis revealed changes in expression of a number of proteins, particularly those involved in cell-cell adhesion. In line with its effects on Caco-2 cell monolayers, fluoride, at 5 mM, also had profound effects on Cl- secretion and transepithelial resistance of both rat and mouse colonic epithelia. Our results show that treatment with fluoride has major effects on the structure, function, and proteome of intestinal epithelia, but only at concentrations considerably higher than those likely to be encountered in vivo, when much lower fluoride doses are normally ingested on a chronic basis
Recommended from our members
Association of Genetic Variants With Primary Open-Angle Glaucoma Among Individuals With African Ancestry.
Importance:Primary open-angle glaucoma presents with increased prevalence and a higher degree of clinical severity in populations of African ancestry compared with European or Asian ancestry. Despite this, individuals of African ancestry remain understudied in genomic research for blinding disorders. Objectives:To perform a genome-wide association study (GWAS) of African ancestry populations and evaluate potential mechanisms of pathogenesis for loci associated with primary open-angle glaucoma. Design, Settings, and Participants:A 2-stage GWAS with a discovery data set of 2320 individuals with primary open-angle glaucoma and 2121 control individuals without primary open-angle glaucoma. The validation stage included an additional 6937 affected individuals and 14 917 unaffected individuals using multicenter clinic- and population-based participant recruitment approaches. Study participants were recruited from Ghana, Nigeria, South Africa, the United States, Tanzania, Britain, Cameroon, Saudi Arabia, Brazil, the Democratic Republic of the Congo, Morocco, Peru, and Mali from 2003 to 2018. Individuals with primary open-angle glaucoma had open iridocorneal angles and displayed glaucomatous optic neuropathy with visual field defects. Elevated intraocular pressure was not included in the case definition. Control individuals had no elevated intraocular pressure and no signs of glaucoma. Exposures:Genetic variants associated with primary open-angle glaucoma. Main Outcomes and Measures:Presence of primary open-angle glaucoma. Genome-wide significance was defined as P < 5 × 10-8 in the discovery stage and in the meta-analysis of combined discovery and validation data. Results:A total of 2320 individuals with primary open-angle glaucoma (mean [interquartile range] age, 64.6 [56-74] years; 1055 [45.5%] women) and 2121 individuals without primary open-angle glaucoma (mean [interquartile range] age, 63.4 [55-71] years; 1025 [48.3%] women) were included in the discovery GWAS. The GWAS discovery meta-analysis demonstrated association of variants at amyloid-β A4 precursor protein-binding family B member 2 (APBB2; chromosome 4, rs59892895T>C) with primary open-angle glaucoma (odds ratio [OR], 1.32 [95% CI, 1.20-1.46]; P = 2 × 10-8). The association was validated in an analysis of an additional 6937 affected individuals and 14 917 unaffected individuals (OR, 1.15 [95% CI, 1.09-1.21]; P < .001). Each copy of the rs59892895*C risk allele was associated with increased risk of primary open-angle glaucoma when all data were included in a meta-analysis (OR, 1.19 [95% CI, 1.14-1.25]; P = 4 × 10-13). The rs59892895*C risk allele was present at appreciable frequency only in African ancestry populations. In contrast, the rs59892895*C risk allele had a frequency of less than 0.1% in individuals of European or Asian ancestry. Conclusions and Relevance:In this genome-wide association study, variants at the APBB2 locus demonstrated differential association with primary open-angle glaucoma by ancestry. If validated in additional populations this finding may have implications for risk assessment and therapeutic strategies
Recommended from our members
Rarity of monodominance in hyperdiverse Amazonian forests.
Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors
- …