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1.
Proteomics ; 23(5): e2200366, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36479858

RESUMO

Crohn's disease (CD) is a chronic condition characterized by recurrent flares of inflammation in the gastrointestinal tract. Disease etiology is poorly understood and is characterized by dysregulated immune activation that progressively destroys intestinal tissue. Key cellular compartments in disease pathogenesis are the intestinal epithelial layer and its underlying lamina propria. While the epithelium contains predominantly epithelial cells, the lamina propria is enriched in immune cells. Deciphering proteome changes in different cell populations is important to understand CD pathogenesis. Here, using isobaric labeling-based quantitative proteomics, we perform an exploratory study to analyze in-depth proteome changes in epithelial cells, immune cells and stromal cells in CD patients compared to controls using cells purified by FACS. Our study revealed increased proteins associated with neutrophil degranulation and mitochondrial metabolism in immune cells of CD intestinal mucosa. We also found upregulation of proteins involved in glycosylation and secretory pathways in epithelial cells of CD patients, while proteins involved in mitochondrial metabolism were reduced. The distinct alterations in protein levels in immune- versus epithelial cells underscores the utility of proteome analysis of defined cell types. Moreover, our workflow allowing concomitant assessment of cell-type specific changes on an individual basis enables deeper insight into disease pathogenesis.


Assuntos
Doença de Crohn , Humanos , Doença de Crohn/metabolismo , Proteoma/metabolismo , Colo/metabolismo , Proteômica , Mucosa Intestinal/metabolismo , Células Epiteliais/metabolismo
2.
Inflammation ; 45(4): 1631-1650, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35190924

RESUMO

Inflammasomes are intracellular protein complexes whose activation results in proinflammatory cytokines. Inflammasomes are implicated in Crohn´s disease (CD) pathogenesis, yet the contribution of inflammasomes in intestinal epithelial cells (IECs) versus lamina propria (LP) macrophages is poorly understood. Whether inflammasome expression in intestinal tissue reflects the serum inflammatory protein profile of patients is also not known. We aimed to determine the intestinal cell types where inflammasome expression is increased in CD and if they correlate with the serum protein profile. RT-PCR and NanoString nCounter technology were used to characterize inflammasome gene expression in CD patients and controls. The mucosa, LP and IEC cell fractions and FACS-sorted cells were analyzed. Proximity extension assay with a 92-protein panel was used to determine the serum inflammatory protein profile. Compositional analysis was used to correlate ileum inflammasome gene expression with intestinal mononuclear phagocyte populations. We show that NLRP3 and MEFV inflammasome sensors and downstream effector expression including IL-1ß are increased in inflamed mucosa of IBD patients and correlate with disease activity. Inflammasome gene expression increased with the abundance of immature intestinal macrophages, and increased IL-1ß released by CD LP cells correlated with immature macrophage frequency. Inflammasome gene expression was also increased in circulating monocytes, the precursors of immature intestinal macrophages. Finally, the serum inflammatory profile of CD patients correlates with ileal expression of genes related to NLRP3 and MEFV inflammasomes. Overall, we show that MEFV and NLRP3 inflammasome expression in CD intestine is attributed to the accumulation of immature macrophages and correlates with serum inflammatory proteins.


Assuntos
Doença de Crohn , Inflamassomos , Macrófagos , Proteínas Sanguíneas/metabolismo , Doença de Crohn/metabolismo , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pirina/genética , Pirina/metabolismo
3.
J Crohns Colitis ; 15(8): 1346-1361, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33537747

RESUMO

BACKGROUND AND AIMS: Uncontrolled activation of intestinal mononuclear phagocytes [MNPs] drives chronic inflammation in inflammatory bowel disease [IBD]. Triggering receptor expressed on myeloid cells 1 [TREM-1] has been implicated in the pathogenesis of IBD. However, the role of TREM-1+ cell subsets in driving IBD pathology and the link with clinical parameters are not understood. We investigated TREM-1 expression in human intestinal MNP subsets and examined blocking TREM-1 as a potential IBD therapy. METHODS: TREM-1 gene expression was analysed in intestinal mucosa, enriched epithelial and lamina propria [LP] layers, and purified cells from controls and IBD patients. TREM-1 protein on immune cells was assessed by flow cytometry and immunofluorescence microscopy. Blood monocyte activation was examined by large-scale gene expression using a TREM-1 agonist or LP conditioned media [LP-CM] from patients in the presence or absence of TREM-1 and tumour necrosis factor [TNF] antagonist antibodies. RESULTS: TREM-1 gene expression increases in intestinal mucosa from IBD patients and correlates with disease score. TREM-1+ cells, which are mainly immature macrophages and CD11b+ granulocytes, increase among LP cells from Crohn's disease patients and their frequency correlates with inflammatory molecules in LP-CM. LP-CM from Crohn's disease patients induces an inflammatory transcriptome in blood monocytes, including increased IL-6 expression, which is reduced by simultaneous blocking of TREM-1 and TNF. CONCLUSIONS: High intestinal TREM-1 expression, reflecting a high frequency of TREM-1+ immature macrophages and TREM-1+CD11b+ granulocytes, is linked to the deleterious inflammatory microenvironment in IBD patients. Therefore, blocking the TREM-1 pathway, especially simultaneously with anti-TNF therapy, has potential as a new IBD therapy.


Assuntos
Doença de Crohn/patologia , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno CD11b/metabolismo , Estudos de Casos e Controles , Feminino , Expressão Gênica , Granulócitos/metabolismo , Humanos , Interleucina-6/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Adulto Jovem
4.
J Phys Condens Matter ; 32(40): 405403, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32628643

RESUMO

We report results from visible and UV Raman spectroscopy studies of the phonon spectra of a polycrystalline sample of the prototypical perovskite type oxide BaZrO3 and a 500 nm thick film of its Y-doped, proton conducting, counterpart BaZr0.8Y0.2O2.9. Analysis of the Raman spectra measured using different excitation energies (between 3.44 eV and 5.17 eV) reveals the activation of strong resonance Raman effects involving all lattice vibrational modes. Specifically, two characteristic energies were identified for BaZrO3, one around 5 eV and one at higher energy, respectively, and one for BaZr0.8Y0.2O2.9, above 5 eV. Apart from the large difference in spectral intensity between the non-resonant and resonant conditions, the spectra are overall similar to each other, suggesting that the vibrational spectra of the perovskites are stable when investigated using an UV laser as excitation source. These results encourage further use of UV Raman spectroscopy as a novel approach for the study of lattice vibrational dynamics and local structure in proton conducting perovskites, and open up for, e.g., time-resolved experiments on thin films targeted at understanding the role of lattice vibrations in proton transport in these kinds of materials.

5.
Oncotarget ; 9(97): 36993-37007, 2018 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-30651930

RESUMO

Increasing knowledge of the function and regulation of tumor-infiltrating lymphocytes has led to new insights in cancer immunotherapy. Regulatory T cells (Treg) accumulate in colon tumors, and we recently showed that CD39+ Treg from cancer patients inhibit transendothelial migration of conventional T cells. CD39 mediates the hydrolysis of ATP to immunosuppressive adenosine and adds to the immunosuppressive effects of Treg. Here, we further investigated the regulatory features of intratumoral CD39+ Treg in colon cancer. Using flow cytometry analyses of cells from 46 colon cancer patients, we confirm the accumulation of CD39+ Treg in the tumor tissue compared to unaffected colon tissue, and also show that tumor-infiltrating Treg express more CD39 and Foxp3 on a per cell basis. Furthermore, CD39+ Treg in tumors express markers indicating increased turnover and suppressive ability. In particular, tumor-infiltrating CD39+ Treg have high expression of surface molecules related to immunosuppression, such as ICOS, PD-L1 and CTLA-4. Functional suppression assays also indicate potent suppressive capacity of CD39+ Treg on proliferation and IFN-γ secretion by conventional T cells. In conclusion, our results identify tumor-infiltrating CD39+ Treg as a numerous and potentially important immunosuppressive subset, and suggest that immunotherapy aimed at reducing the activity of CD39+ Treg may be particularly useful in the setting of colon cancer.

6.
Immun Inflamm Dis ; 4(2): 191-200, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27957327

RESUMO

Several Butyrophilin (BTN) and Btn-like (BTNL) molecules control T lymphocyte responses, and are genetically associated with inflammatory disorders and cancer. In this study, we present a comprehensive expression analysis of human and murine BTN and BTNL genes in conditions associated with intestinal inflammation and cancer. Using real-time PCR, expression of human BTN and BTNL genes was analyzed in samples from patients with ulcerative colitis, irritable bowel syndrome, and colon tumors. Expression of murine Btn and Btnl genes was examined in mouse models of spontaneous colitis (Muc2-/-) and intestinal tumorigenesis (ApcMin/+). Our analysis indicates a strong association of several of the human genes with ulcerative colitis and colon cancer; while especially BTN1A1, BTN2A2, BTN3A3, and BTNL8 were significantly altered in inflammation, colonic tumors exhibited significantly decreased levels of BTNL2, BTNL3, BTNL8, and BTNL9 as compared to unaffected tissue. Colonic inflammation in Muc2-/- mice significantly down-regulated the expression of particularly Btnl1, Btnl4, and Btnl6 mRNA, and intestinal polyps derived from ApcMin/+ mice displayed altered levels of Btn1a1, Btn2a2, and Btnl1 transcripts. Thus, our data present an association of BTN and BTNL genes with intestinal inflammation and cancer and represent a valuable resource for further studies of this gene family.


Assuntos
Butirofilinas/metabolismo , Neoplasias do Colo/metabolismo , Inflamação/metabolismo , Animais , Colite Ulcerativa/metabolismo , Colo , Humanos , Mucosa Intestinal , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T
7.
Biomed Res Int ; 2016: 5989128, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26885508

RESUMO

INTRODUCTION: The aetiology and pathogenesis of ulcerative colitis (UC) are essentially unknown. Galectins are carbohydrate-binding lectins involved in a large number of physiological and pathophysiological processes. Little is known about the role of galectins in human UC. In this immunohistochemical exploratory study, both epithelial and inflammatory cell galectin expression were studied in patients with a thoroughly documented clinical history and were correlated with inflammatory activity. MATERIAL AND METHODS: Surgical whole intestinal wall colon specimens from UC patients (n = 22) and controls (n = 10) were studied. Clinical history, pharmacological treatment, and modified Mayo-score were recorded. Tissue inflammation was graded, and sections were stained with antibodies recognizing galectin-1, galectin-2, galectin-3, and galectin-4. RESULTS: Galectin-1 was undetectable in normal and UC colonic epithelium, while galectin-2, galectin-3, and galectin-4 were strongly expressed. A tendency towards diminished epithelial expression with increased inflammatory grade for galectin-2, galectin-3, and galectin-4 was also found. In the inflammatory cells, a strong expression of galectin-2 and a weak expression of galectin-3 were seen. No clear-cut correlation between epithelial galectin expression and severity of the disease was found. CONCLUSION: Galectin expression in patients with UC seems to be more dependent on disease focality and individual variation than on degree of tissue inflammation.


Assuntos
Colite Ulcerativa/genética , Galectina 1/biossíntese , Galectina 2/biossíntese , Galectina 3/biossíntese , Galectina 4/biossíntese , Adulto , Colectomia , Colite Ulcerativa/patologia , Colite Ulcerativa/cirurgia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Galectina 1/genética , Galectina 2/genética , Galectina 3/genética , Galectina 4/genética , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/patologia , Inflamação/cirurgia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino
8.
Cancer Immunol Res ; 4(3): 183-93, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26787824

RESUMO

T cell-mediated immunity is a major component of antitumor immunity. In order to be efficient, effector T cells must leave the circulation and enter into the tumor tissue. Regulatory T cells (Treg) from gastric cancer patients, but not from healthy volunteers, potently inhibit migration of conventional T cells through activated endothelium. In this study, we compared T cells from colon cancer patients and healthy donors to determine the mechanisms used by Tregs from cancer patients to inhibit conventional T-cell migration. Our results showed that circulating Tregs from cancer patients expressed high levels of CD39, an ectoenzyme mediating hydrolysis of ATP to AMP, as a rate-determining first step in the generation of immunosuppressive adenosine. Tumor-associated Tregs expressed even more CD39, and we therefore examined the importance of adenosine in Treg-mediated inhibition of T-cell transendothelial migration in vitro. Exogenous adenosine significantly reduced migration of conventional T cells from healthy volunteers, and blocking either adenosine receptors or CD39 enzymatic activity during transmigration restored the ability of conventional T cells from cancer patients to migrate. Adenosine did not directly affect T cells or endothelial cells, but reduced the ability of monocytes to activate the endothelium. Taken together, our results indicate that Treg-derived adenosine acts on monocytes and contributes to reduced transendothelial migration of effector T cells into tumors. This effect of Tregs is specific for cancer patients, and our results indicate that Tregs may affect not only T-cell effector functions but also their migration into tumors.


Assuntos
Adenocarcinoma/imunologia , Adenosina/fisiologia , Neoplasias do Colo/imunologia , Linfócitos T Reguladores/fisiologia , Migração Transendotelial e Transepitelial , Adenocarcinoma/patologia , Antígenos CD/metabolismo , Apirase/metabolismo , Células Cultivadas , Técnicas de Cocultura , Neoplasias do Colo/patologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos
9.
J Immunol ; 195(7): 3472-81, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26297765

RESUMO

Mucosa-associated invariant T (MAIT) cells are innate-like T cells with a conserved TCR α-chain recognizing bacterial metabolites presented on the invariant MHC-related 1 molecule. MAIT cells are present in intestinal tissues and liver, and they rapidly secrete IFN-γ and IL-17 in response to bacterial insult. In colon cancer, IL-17-driven inflammation promotes tumor progression, whereas IFN-γ production is essential for antitumor immunity. Thus, tumor-associated MAIT cells may affect antitumor immune responses by their secreted cytokines. However, the knowledge of MAIT cell presence and function in tumors is virtually absent. In this study, we determined the frequency, phenotype, and functional capacity of MAIT cells in colon adenocarcinomas and unaffected colon lamina propria. Flow cytometric analyses showed significant accumulation of MAIT cells in tumor tissue, irrespective of tumor stage or localization. Colonic MAIT cells displayed an activated memory phenotype and expression of chemokine receptors CCR6 and CCR9. Most MAIT cells in unaffected colon tissues produced IFN-γ, whereas only few produced IL-17. Colonic MAIT cells also produced TNF-α, IL-2, and granzyme B. In the tumors, significantly lower frequencies of IFN-γ-producing MAIT cells were seen, whereas there were no differences in the other cytokines analyzed, and in vitro studies showed that secreted factors from tumor tissue reduced IFN-γ production from MAIT cells. In conclusion, MAIT cells infiltrate colon tumors but their ability to produce IFN-γ is substantially reduced. We suggest that MAIT cells have the capacity to promote local immune responses to tumors, but factors in the tumor microenvironment act to reduce MAIT cell IFN-γ production.


Assuntos
Adenocarcinoma/patologia , Neoplasias do Colo/patologia , Interferon gama/biossíntese , Mucosa Intestinal/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Granzimas/biossíntese , Humanos , Inflamação/imunologia , Interferon gama/imunologia , Interleucina-17/biossíntese , Interleucina-17/imunologia , Interleucina-2 , Mucosa Intestinal/citologia , Fígado/citologia , Fígado/imunologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Receptores CCR/biossíntese , Receptores CCR6/biossíntese , Subpopulações de Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/biossíntese
10.
Scand J Gastroenterol ; 50(5): 528-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25648657

RESUMO

OBJECTIVE: Patients who undergo ileal pouch-anal anastomosis (IPAA) after colectomy for ulcerative colitis (UC) occasionally have neoplasia in the IPAA. Patients with evidence of dysplasia or carcinoma in the colorectal specimen may have an increased risk of such neoplasia. A surveillance program has been suggested. The aims of this study were to evaluate the outcomes of surveillance of a large patient cohort, and to investigate the prevalences of neoplasia in the ileal pouch mucosa and in the anal transitional zone (ATZ). MATERIAL AND METHODS: A total of 629 patients underwent IPAA for UC at Sahlgrenska University Hospital, Gothenburg, Sweden. Identified from a register, 73 patients with neoplasia in their specimen considered eligible for the trial were prospectively enrolled, and underwent clinical examination, endoscopy with macroscopic evaluation, and mucosal biopsies from the ileal pouch and the ATZ. The biopsies were independently evaluated by two experienced gastro-pathologists. RESULTS: In all, 56 patients (39 males) with a median follow-up time of 18 (range, 1-29) years were evaluated. One patient (1.8%; 95% CI 0%-5.3%) showed low-grade dysplasia in the pouch, as recorded by one of the two pathologists. The individual pathologists recorded indefinite for dysplasia (IFD) in the pouch for 19 and 20 patients, respectively, and IFD in the ATZ for 2 and 4 patients, respectively. None of the biopsies showed evidence of high-grade dysplasia (HGD) or carcinoma. CONCLUSIONS: Neoplasia in the ileal pouch or ATZ after IPAA for UC is rare in the proposed risk group. The necessity for and value of a routine surveillance program should be prospectively evaluated.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Carcinoma/patologia , Colite Ulcerativa/patologia , Bolsas Cólicas/patologia , Proctocolectomia Restauradora/efeitos adversos , Adulto , Idoso , Canal Anal/patologia , Biópsia , Colite Ulcerativa/cirurgia , Feminino , Seguimentos , Humanos , Íleo/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Suécia
11.
Cancer Immunol Immunother ; 62(11): 1687-95, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24013383

RESUMO

Recruitment of immune cells to tumors is a complex process crucial for both inflammation-driven tumor progression and specific anti-tumor cytotoxicity. Chemokines control the directed migration of immune cells, and their actions are partly controlled by nonsignaling chemokine decoy receptors. The role of the receptors such as D6, Duffy antigen receptor for chemokines and ChemoCentryx chemokine receptor in immunity to tumors is still unclear. Using real-time PCR, we detected significantly decreased expression of D6 mRNA in colon tumors compared to unaffected mucosa. D6 protein was expressed by lymphatic endothelium and mononuclear cells in the colon lamina propria and detected by immunohistochemistry in two out of six tissue samples containing high D6 mRNA levels, whereas no staining was observed in any tissue samples expressing low mRNA levels. When examining the density of lymphatic vessels in colon tumors, we detected a marked increase in vessels identified by the lymphatic endothelial marker Lyve-1, excluding passive regulation of D6 due to decreased lymphatic vessel density. In parallel, the Treg-recruiting chemokine CCL22, which is sequestered by D6, was threefold increased in tumor tissue. Furthermore, we could show that low D6 expression correlated to more invasive tumors and that tumor location influences D6 expression, which is lower in the more distal parts of the colon. The data support that regulation of D6 by colon tumors results in altered levels of proinflammatory CC chemokines, thereby shaping the local chemokine network to favor tumor survival. This may have implications for the design of future immunotherapy for colon cancer.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Receptores CCR10/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiocina CCL22/genética , Quimiocina CCL22/metabolismo , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Receptores CCR10/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor D6 de Quimiocina
12.
Cancer Immunol Immunother ; 62(6): 989-97, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23591979

RESUMO

Local inflammation is a strong risk factor for the development of gastrointestinal adenocarcinomas. Mucosal regulatory T cells and IgA-secreting cells both contribute to reduce inflammatory responses, and their recruitment to tissues is dependent on local production of chemokines. More specifically, IgA-secreting cells are recruited to mucosal tissues by CCL28 signalling through CCR10. Here, we examined the recruitment of IgA-secreting plasma cells to tumor-associated mucosa in patients suffering from colon adenocarcinoma. Flow cytometric analyses of single cell suspensions from tumor-associated and unaffected colon mucosa showed a marked decrease in CD19(+)CD38(high)IgA(+) plasmablasts in the tumor-associated mucosa, while the total frequencies of B and T cells were similar. This finding was confirmed in ELISPOT assays, demonstrating a 64 % reduction in the frequencies of IgA-secreting cells among cells from the tumor-associated mucosa. The few IgA(+) plasmablasts present in the tumor did not express CCR10, and functional migration assays demonstrated that IgA-secreting cells from tumor-associated mucosa did not migrate in response to CCL28. Taken together, our results show an impaired migration of IgA-secreting cells to colon tumors, presumably caused by a decreased production of CCL28 in the tumor. The lack of local IgA antibodies may lead to impaired barrier function and increased bacterial colonization, driving further inflammatory responses and promoting tumor growth.


Assuntos
Adenocarcinoma/imunologia , Quimiotaxia de Leucócito/imunologia , Neoplasias do Colo/imunologia , Imunoglobulina A Secretora/biossíntese , Plasmócitos/imunologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Quimiocinas CC/imunologia , Quimiocinas CC/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Humanos , Imunofenotipagem , Mucosa Intestinal/imunologia , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Plasmócitos/metabolismo , Receptores CCR10/metabolismo
13.
J Chem Phys ; 136(9): 094514, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22401459

RESUMO

We here present a statistical model of hydrogen bond induced network structures in liquid alcohols. The model generalises the Andersson-Schulz-Flory chain model to allow also for branched structures. Two bonding probabilities are assigned to each hydroxyl group oxygen, where the first is the probability of a lone pair accepting an H-bond and the second is the probability that given this bond also the second lone pair is bonded. The average hydroxyl group cluster size, cluster size distribution, and the number of branches and leaves in the tree-like network clusters are directly determined from these probabilities. The applicability of the model is tested by comparison to cluster size distributions and bonding probabilities obtained from Monte Carlo simulations of the monoalcohols methanol, propanol, butanol, and propylene glycol monomethyl ether, the di-alcohol propylene glycol, and the tri-alcohol glycerol. We find that the tree model can reproduce the cluster size distributions and the bonding probabilities for both mono- and poly-alcohols, showing the branched nature of the OH-clusters in these liquids. Thus, this statistical model is a useful tool to better understand the structure of network forming hydrogen bonded liquids. The model can be applied to experimental data, allowing the topology of the clusters to be determined from such studies.

14.
PLoS One ; 7(2): e30695, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22319577

RESUMO

BACKGROUND: Colorectal cancer usually gives rise to a specific anti-tumor immune response, but for unknown reasons the resulting immunity is not able to clear the tumor. Recruitment of activated effector lymphocytes to the tumor is important for efficient anti-tumor responses, while the presence of regulatory T cells (Treg) down-modulate tumor-specific immunity. We therefore aimed to determine homing mechanisms and activation stage of Treg and effector T cell infiltrating colon tumors compared to cells from the unaffected mucosa in patients suffering from colon adenocarcinoma. METHODOLOGY/PRINCIPAL FINDINGS: Lymphocytes were isolated from unaffected and tumor mucosa from patients with colon adenocarcinoma, and flow cytometry, immunohistochemistry, and quantitative PCR was used to investigate the homing mechanisms and activation stage of infiltrating Treg and conventional lymphocytes. We detected significantly higher frequencies of CD25(high)FOXP3⁺CD127(low) putative Treg in tumors than unaffected mucosa, which had a complete demethylation in the FOXP3 promotor. Tumor-associated Treg had a high expression of CTLA-4, and some appeared to be antigen experienced effector/memory cells based on their expression of αEß7 (CD103). There were also significantly fewer activated T cells and more CTLA-4⁺ conventional T cells susceptible to immune regulation in the tumor-associated mucosa. In contrast, CD8⁺granzyme B⁺ putative cytotoxic cells were efficiently recruited to the tumors. The frequencies of cells expressing α4ß7 and the Th1 associated chemokine receptor CXCR3 were significantly decreased among CD4⁺ T cells in the tumor, while frequencies of CD4⁺CCR4⁺ lymphocytes were significantly increased. CONCLUSIONS/SIGNIFICANCE: This study shows that CCR4⁺CTLA4(hi) Treg accumulate in colon tumors, while the frequencies of activated conventional Th1 type T cells are decreased. The altered lymphocyte composition in colon tumors will probably diminish the ability of the immune system to effectively attack tumor cells, and reducing the Treg activity is an important challenge for future immunotherapy protocols.


Assuntos
Adenocarcinoma Mucinoso/imunologia , Neoplasias do Colo/imunologia , Ativação Linfocitária/imunologia , Linfócitos T Reguladores/imunologia , Adenocarcinoma/imunologia , Antígeno CTLA-4 , Humanos , Imunidade , Subunidade alfa de Receptor de Interleucina-2 , Mucosa , Receptores CCR4 , Linfócitos T/imunologia
15.
J Crohns Colitis ; 5(5): 407-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21939914

RESUMO

BACKGROUND AND AIMS: Failure of ileal pouch-anal anastomosis (IPAA) occurs in around 10% of the patients. Compared to patients with functioning pouches, health related quality of life is deteriorated after failure. Sexual function in patients with pouch failure is however poorly studied. The aim was to study sexual function in patients with pelvic pouch failure; patients with functioning pouches were used as controls. The hypothesis was that patients with pouch failure have worse sexual function. METHODS: 36 patients with pouch failure were compared with 72 age and sex-matched controls with ulcerative colitis and functioning pouches. The patients answered a set of questionnaires concerning sexual function (Female Sexual Function Index [FSFI] and International Index of Erectile Function [IIEF]), body image (BIS-scale) and health-related quality of life (SF-36). RESULTS: Both women and men with pouch failure scored lower than controls in the FSFI and IIEF questionnaires. However, none of the observations were statistically significant. The scores in the failure group (for both sexes) were below the cut-off level for sexual dysfunction. Scores for the BIS instrument were significantly lower for both sexes in the failure group. Women and men in the failure group scored lower than the controls in all domains of the SF-36, however statistically significant only for the social function domain in men. CONCLUSIONS: The hypothesis, that a failed IPAA is associated with worse sexual function, was not confirmed. Compared to patients with functioning pouches, patients with pouch failure have inferior body image.


Assuntos
Colite Ulcerativa/cirurgia , Bolsas Cólicas , Doença de Crohn/cirurgia , Complicações Pós-Operatórias , Proctocolectomia Restauradora , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Psicogênicas/etiologia , Adulto , Idoso , Imagem Corporal , Estudos de Casos e Controles , Colite Ulcerativa/psicologia , Doença de Crohn/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proctocolectomia Restauradora/psicologia , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e Questionários , Falha de Tratamento
17.
J Phys Chem B ; 113(32): 11247-51, 2009 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-19621942

RESUMO

The phase behavior and the ionic conductivity of ionic liquids (ILs) of the N-alkyl-N-alkylpyrrolidinium (PYR(xy)) cation and the bis(trifluoromethanesulfonyl)imide (TFSI) anion are investigated upon addition of LiTFSI salt. We compare the case of two new ILs of the PYR(2y) cation (where 2 is ethyl and y is butyl or propyl) with that of the PYR(14) (where 1 is methyl and 4 is butyl). We find that the addition of LiTFSI increases the glass transition temperature, decreases the melting temperature and the heat of fusion and, in the ILs of the PYR(2y) family, suppresses crystallization. In the solid state, significant ionic conductivities are found, being as high as 10(-5) S cm(-1), strongly increasing with Li(+) concentration. The opposite trend is found in the liquid state, where the conductivity is on the order of 10(-3)-10(-2) S cm(-1) at room temperature. A T(g)-scaled Arrhenius plot shows that the liquid-state ionic conductivity in these systems is mainly governed by viscosity and that the fragility of the liquids is slightly influenced by the structural modifications on the cation.

18.
J Phys Chem B ; 111(43): 12462-7, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17927237

RESUMO

We have investigated the physical properties of proton conducting polymer membranes based on a protic ionic liquid (IL). Properties such as ionic conductivity, melting point of the polymer phase, and glass transition temperature of the liquid phase are studied as a function of IL/polymer ratio and temperature. We observe an increased thermomechanical stability of the membrane with increasing polymer content. However, there is a concomitant decrease in the conductivity with increasing polymer content. This decrease is larger than what can be expected from the dilution of the conducting IL by the insulating polymer matrix. The origin of this decrease can be caused both by the morphology of the membrane and by interactions between the polymer matrix and the ionic liquid. We find a change in the glass transition temperature and in the temperature dependence of the conductivity with increasing polymer content. Both effects can be related to the physical confinement of the IL in the polymer membrane.


Assuntos
Líquidos Iônicos/química , Membranas Artificiais , Polímeros/química , Prótons , Varredura Diferencial de Calorimetria , Condutividade Elétrica , Eletrólitos/química , Espectrofotometria Infravermelho , Termodinâmica
19.
Dis Colon Rectum ; 50(10): 1545-52, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17762968

RESUMO

PURPOSE: This study was designed to investigate long-term pouch function and health-related quality of life in a single, large cohort of patients with ileal pouch-anal anastomosis for ulcerative colitis. METHODS: Data from 370 patients were included in the study. Thirty-nine patients (11 percent) did not have a functioning pouch (failures) but were included in the health-related quality of life analyses. Pouch function (Oresland score) and health-related quality of life (Short Form-36) were evaluated by postal questionnaires. A total of 88 percent of the patients with a functioning ileal pouch-anal anastomosis returned the questionnaires vs. 76 percent of the failures. Median follow-up time after ileal pouch-anal anastomosis was 15 years vs. 11 years after failure. An age-matched and gender-matched reference sample (n = 286) was randomly drawn from the Swedish Short Form-36 database. RESULTS: Median bowel frequency was six per 24 hours: 76 percent emptied the reservoir at night, 23 percent had urgency, 12 percent had evacuation difficulties, and 17 percent experienced soiling during the day. Fifty-two percent of the males and 32 percent of the females suffered from soiling at night. More than one-half of the patients had occasional perianal soreness, 6 percent considered the pouch to be a social handicap, and 94 percent were satisfied with their pouch. Patients with a functioning ileal pouch-anal anastomosis did not differ from the reference sample on any Short Form-36 domain, except for a reduced score in General Health (P = 0.02). Pouch function was positively correlated to health-related quality of life. Patients with pouch failure had reduced health-related quality of life in most domains. CONCLUSIONS: Patients' satisfaction is high and functional outcome is good after ileal pouch-anal anastomosis. Poor pouch function affects health-related quality of life negatively. Patients with failure after ileal pouch-anal anastomosis are substantially limited in a variety of health-related quality of life domains.


Assuntos
Colite Ulcerativa/cirurgia , Bolsas Cólicas , Nível de Saúde , Proctocolectomia Restauradora , Qualidade de Vida , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Fatores de Tempo , Resultado do Tratamento
20.
Environ Res ; 105(3): 324-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17674967

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) in crude oil cause a range of adverse effects in oiled seabirds, one of the most common being hemolytic anemia via oxidative attack of erythrocytes by PAH metabolites resulting in hemoglobin leakage and formation of Heinz bodies. In such cases, haptoglobin and ferritin are up-regulated to sequester free Hb and iron in the circulation. We investigated these plasma proteins as biomarkers of PAH-induced Heinz body hemolytic anemia in oiled seabirds. Concentration ranges of PAHs, HAP and FT in plasma samples were 10-184 ng/ml, 0-2.6 mg/ml and 0-7.6 ng/ml, respectively. Dose-response relationships between plasma PAH exposure and haptoglobin and ferritin (FT) were investigated, and evidence of erythrocyte Heinz body formation studied in 50 oiled common guillemots stranded on the Norfolk Wash coast (East England). Haptoglobin was negatively correlated, and FT was positively correlated with PAH exposure. Heinz bodies were also observed confirming the toxic mechanism causing hemolytic anemia and counts were positively correlated with exposure. Our results support the application of these complementary biomarkers to assess hemolytic effects of oiling in wildlife biomonitoring, which also discriminate the influence of hemolytic versus inflammatory effects in oiled guillemots.


Assuntos
Anemia Hemolítica/veterinária , Doenças das Aves/epidemiologia , Charadriiformes/sangue , Corpos de Heinz/metabolismo , Petróleo/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Poluição Química da Água/análise , Acidentes , Anemia Hemolítica/sangue , Anemia Hemolítica/epidemiologia , Animais , Animais Selvagens , Biomarcadores/sangue , Doenças das Aves/sangue , Aves , Relação Dose-Resposta a Droga , Inglaterra , Monitoramento Ambiental/métodos , Monitoramento Epidemiológico , Ferritinas/metabolismo , Haptoglobinas/metabolismo , Corpos de Heinz/química , Hemoglobinas/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/efeitos adversos
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