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1.
J Endocrinol Invest ; 45(6): 1161-1172, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35072927

RESUMO

PURPOSE: Female sexual response involves a complex interplay between neurophysiological mechanisms and the nitric oxide (NO)-mediated relaxation of clitoris and vagina. The aim of this study was to evaluate sex steroids regulation of the relaxant pathway in vagina, using a validated animal model. METHODS: Subgroups of OVX Sprague-Dawley rats were treated with 17ß-estradiol, testosterone, or testosterone and letrozole, and compared with a group of intact animals. Masson's trichrome staining was performed for morphological evaluation of the distal vaginal wall, in vitro contractility studies investigated the effect of OVX and in vivo treatments on vaginal smooth muscle activity. RNA from vaginal tissue was analyzed by semi-quantitative RT-PCR. RESULTS: Immunohistochemical analysis showed that OVX induced epithelial and smooth muscle structural atrophy, testosterone and testo + letrozole increased the muscle bundles content and organization without affecting the epithelium while 17ß-estradiol mediated the opposite effects. In vitro contractility studies were performed on noradrenaline pre-contracted vaginal strips from each experimental group. Acetylcholine (0.001-10 µM) stimulation induced a concentration-dependent relaxation, significantly reduced by NO-synthase inhibitor L-NAME and by guanylate cyclase inhibitor ODQ. OVX resulted in a decreased responsiveness to acetylcholine, restored by testosterone, with or without letrozole, but not by 17ß-estradiol. OVX sensitivity to the NO-donor SNP was higher than in the control. Vardenafil, a PDE5 inhibitor, enhanced SNP effect in OVX + testosterone as well as in control, as supported by RNA expression analysis. CONCLUSIONS: Our study demonstrates that testosterone improves the NO-mediated smooth muscle vaginal cells relaxation confirming its role in maintaining the integrity of muscular relaxant machinery.


Assuntos
Acetilcolina , Óxido Nítrico , Animais , Estradiol/farmacologia , Feminino , Humanos , Letrozol/farmacologia , Óxido Nítrico/metabolismo , Ovariectomia , RNA , Ratos , Ratos Sprague-Dawley , Testosterona/farmacologia , Vagina/metabolismo
2.
J Endocrinol Invest ; 44(10): 2175-2193, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33586025

RESUMO

PURPOSE: Low free testosterone (T) level in men is independently associated with presence and severity of Non-Alcoholic Steatohepatitis (NASH). The histological and molecular effects of oral testosterone prodrug LPCN 1144 treatment on hepatic fibrosis and NASH features are unknown. A metabolic syndrome-induced NASH model in rabbits consuming high fat diet (HFD) has been previously used to assess treatment effects of injectable T on hepatic fibrosis and NASH features. Here we present results on LPCN 1144 in this HFD-induced, NASH preclinical model. METHODS: Male rabbits were randomly assigned to five groups: regular diet (RD), HFD, HFD + 1144 vehicle (HFD + Veh), HFD + 1144 (1144), and HFD + 1144 + α-tocopherol (1144 + ALPHA). Rabbits were sacrificed after 12 weeks for liver histological, biochemical and genetic analyses. Histological scores were obtained through Giemsa (inflammation), Masson's trichrome (steatosis and ballooning), and Picrosirius Red (fibrosis) staining. RESULTS: Compared to RD, HFD and HFD + Veh significantly worsened NASH features and hepatic fibrosis. Considering HFD and HFD + Veh arms, histological and biomarker features were not significantly different. Both 1144 and 1144 + ALPHA arms improved mean histological scores of NASH as compared to HFD arm. Importantly, percentage of fibrosis was improved in both 1144 (p < 0.05) and 1144 + ALPHA (p = 0.05) treatment arms vs. HFD. Both treatment arms also reduced HFD-induced inflammation and fibrosis mRNA markers. Furthermore, 1144 treatments significantly improved HFD-induced metabolic dysfunctions. CONCLUSIONS: Histological and biomarker analyses demonstrate that LPCN 1144 improved HFD-induced hepatic fibrosis and NASH biochemical, biomolecular and histochemical features. These preclinical findings support a therapeutic potential of LPCN 1144 in the treatment of NASH and of hepatic fibrosis.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fibrose/tratamento farmacológico , Inflamação/tratamento farmacológico , Síndrome Metabólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Testosterona/análogos & derivados , Androgênios/farmacologia , Animais , Fibrose/etiologia , Fibrose/patologia , Inflamação/etiologia , Inflamação/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Pró-Fármacos/farmacologia , Coelhos , Testosterona/farmacologia
3.
Psychol Med ; 50(7): 1057-1061, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32375908

RESUMO

Artificial intelligence has dramatically changed the world as we know it, but is yet to fully embrace 'hot' cognition, i.e., the way an intelligent being's thinking is affected by their emotional state. Artificial intelligence encompassing hot cognition will not only usher in enhanced machine-human interactions, but will also promote a much needed ethical approach. Theory of Mind, the ability of the human mind to attribute mental states to others, is a key component of hot cognition. To endow machines with (limited) Theory of Mind capabilities, computer scientists will need to work closely with psychiatrists, psychologists and neuroscientists. They will need to develop new models, but also to formally define what problems need to be solved and how the results should be assessed.


Assuntos
Inteligência Artificial/ética , Teoria da Mente , Humanos
4.
J Endocrinol Invest ; 42(8): 951-965, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30674010

RESUMO

BACKGROUND: Activation of the farnesoid X receptor (FXR), a member of the nuclear receptor steroid superfamily, leads to anti-inflammatory and anti-fibrotic effects in several tissues, including the lung. We have recently demonstrated a protective effect of the farnesoid X receptor (FXR) agonist obeticholic acid (OCA) in rat models of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) and bleomycin-induced pulmonary fibrosis. The aim of the present study was to investigate whether the positive effects of OCA treatment could be exerted also in established MCT-induced PAH, i.e., starting treatment 2 weeks after MCT administration. METHODS: Rats with MCT-induced PAH were treated, 2 weeks after MCT administration, with OCA or tadalafil for two additional weeks. Pulmonary functional tests were performed at week 2 (before treatment) and four (end of treatment). At the same time points, lung morphological features and expression profile of genes related to smooth muscle relaxation/contraction and tissue remodeling were also assessed. RESULTS: 2 weeks after MCT-induced injury, the treadmill resistance (a functional parameter related to pulmonary hypertension) was significantly decreased. At the same time point, we observed right ventricular hypertrophy and vascular remodeling, with upregulation of genes related to inflammation. At week 4, we observed a further worsening of the functional and morphological parameters, accompanied by dysregulation of inflammatory and extracellular matrix markers mRNA expression. Administration of OCA (3 or 10 mg/kg/day), starting 2 weeks after MCT-induced injury, significantly improved pulmonary function, effectively normalizing the exercise capacity. OCA also reverted most of the lung alterations, with a significant reduction of lung vascular wall thickness, right ventricular hypertrophy, and restoration of the local balance between relaxant and contractile pathways. Markers of remodeling pathways were also normalized by OCA treatment. Notably, results with OCA treatment were similar, or even superior, to those obtained with tadalafil, a recently approved treatment for pulmonary hypertension. CONCLUSIONS: The results of this study demonstrate a significant therapeutic effect of OCA in established MCT-induced PAH, improving exercise capacity associated with reduction of right ventricular hypertrophy and lung vascular remodeling. Thus, OCA dosing in a therapeutic protocol restores the balance between relaxant and contractile pathways in the lung, promoting cardiopulmonary protective actions in MCT-induced PAH.


Assuntos
Ácido Quenodesoxicólico/análogos & derivados , Modelos Animais de Doenças , Hipertensão Pulmonar/tratamento farmacológico , Monocrotalina/toxicidade , Fibrose Pulmonar/tratamento farmacológico , Receptores Citoplasmáticos e Nucleares/agonistas , Animais , Antibióticos Antineoplásicos/toxicidade , Bleomicina/toxicidade , Ácido Quenodesoxicólico/farmacologia , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/patologia , Masculino , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Ratos , Ratos Sprague-Dawley
5.
J Endocrinol Invest ; 42(3): 283-294, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29923060

RESUMO

PURPOSE: We recently demonstrated a protective effect of the farnesoid X receptor agonist obeticholic acid (OCA) in rat models of bleomycin-induced pulmonary fibrosis (PF). Aim of the present study was to investigate whether the positive effects of OCA treatment are apparent also on ongoing bleomycin-induced PF, i.e., after 2 weeks of bleomycin administration. METHODS: Bleomycin-induced PF rats were treated 2 weeks after bleomycin administration with OCA or pirfenidone for two additional weeks. Pulmonary function test was performed at 2 and 4 weeks in all experimental groups. At the same time points, lung morphological features and mRNA expression profile of genes related to fibrosis, inflammation and epithelial-mesenchymal transition were also assessed. RESULTS: After 2 weeks, bleomycin significantly increased the pressure at the airway opening (PAO), a functional parameter related to fibrosis-induced lung stiffness, and induced diffuse lung interstitium fibrosis, with upregulation of inflammation (IL1ß, MCP1) and tissue remodeling (COL1A1, COL3A1, ET1, MMP7, PDGFa, αSMA, SNAI1) markers. At week four, a further increase of lung fibrosis and PAO was observed, accompanied by upregulation of extracellular matrix-related mRNA expression. OCA administration, even after the establishment of PF, significantly improved pulmonary function, normalizing PAO, and reverted the bleomycin-induced lung alterations, with significant reduction of markers of inflammation (CD206, COX2, HIF1, IL1ß, MCP1), epithelial proliferation (CTGF, PDGFa) and fibrosis (COL1A1, COL3A1, ET1, FN1, MMPs, αSMA, SNAIs, TGFß1, TIMPs). Results with OCA were similar or superior to those obtained with pirfenidone. CONCLUSIONS: In conclusion, our results demonstrate a significant therapeutic effect of OCA in already established PF.


Assuntos
Biomarcadores/metabolismo , Bleomicina/toxicidade , Ácido Quenodesoxicólico/análogos & derivados , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/toxicidade , Ácido Quenodesoxicólico/farmacologia , Masculino , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Ratos , Ratos Sprague-Dawley
6.
Br J Anaesth ; 121(3): 581-587, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30115256

RESUMO

BACKGROUND: Colloid solutions have been associated with kidney dysfunction in septic animals and humans. The present study investigated the influence of resuscitation with human albumin (HA) 5%, hydroxyethyl starch (HES) 130/0.4 6%, and balanced crystalloids on ultrastructural kidney damage, kidney function, and survival in a model of ovine septic shock. METHODS: After induction of peritoneal septic shock, animals were randomised to one of the following groups: (1) HA 5%, (2) HES 130/0.4 6%, (3) balanced crystalloid, and (4) control (each n=10). Causal therapy included re-laparotomy, peritoneal lavage, and antimicrobial therapy. Sequential kidney biopsies were obtained for the assessment of the electron microscopic tubular injury (EMTI) score. RESULTS: Serum creatinine and urea were highest in the control group, and there were no differences between the intervention groups. Cumulative diuresis was significantly higher in the HA group [1.0 ml kg-1 h-1 (0.6; 1.2)] compared with control [0.7 ml kg-1 h-1 (0.6; 0.9), P<0.05]. Creatinine clearance was highest in the HA and crystalloid groups. Ultrastructural kidney damage was highest in the control group [EMTI score 7.8 (6.7; 9.0)] without differences between intervention groups. Survival was 100% in the colloid groups vs 90% (crystalloid) and 60% (control, all P<0.05). CONCLUSION: In an ovine model of septic shock, kidney function and cumulative diuresis were preserved in the 5% albumin and crystalloid resuscitation groups, whereas HES 130/0.4 6% resulted in diminished creatinine clearance. Differences in kidney function between resuscitation fluids could not be explained by differences in ultrastructural kidney damage. CLINICAL TRIAL REGISTRATION: 84-02.04.2011.A300.


Assuntos
Injúria Renal Aguda/etiologia , Soluções Cristaloides/toxicidade , Derivados de Hidroxietil Amido/toxicidade , Albumina Sérica Humana/toxicidade , Choque Séptico/terapia , Injúria Renal Aguda/fisiopatologia , Animais , Creatinina/sangue , Soluções Cristaloides/uso terapêutico , Modelos Animais de Doenças , Esquema de Medicação , Feminino , Hidratação/efeitos adversos , Hidratação/métodos , Hemodinâmica/fisiologia , Derivados de Hidroxietil Amido/uso terapêutico , Norepinefrina/administração & dosagem , Consumo de Oxigênio/fisiologia , Distribuição Aleatória , Albumina Sérica Humana/uso terapêutico , Carneiro Doméstico , Choque Séptico/fisiopatologia , Vasoconstritores/administração & dosagem
7.
Am J Transplant ; 17(6): 1476-1489, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28009481

RESUMO

Systemic administration of autologous regulatory dendritic cells (DCreg; unpulsed or pulsed with donor antigen [Ag]), prolongs allograft survival and promotes transplant tolerance in rodents. Here, we demonstrate that nonhuman primate (NHP) monocyte-derived DCreg preloaded with cell membrane vesicles from allogeneic peripheral blood mononuclear cells induce T cell hyporesponsiveness to donor alloantigen (alloAg) in vitro. These donor alloAg-pulsed autologous DCreg (1.4-3.6 × 106 /kg) were administered intravenously, 1 day before MHC-mismatched renal transplantation to rhesus monkeys treated with costimulation blockade (cytotoxic T lymphocyte Ag 4 immunoglobulin [CTLA4] Ig) and tapered rapamycin. Prolongation of graft median survival time from 39.5 days (no DCreg infusion; n = 6 historical controls) and 29 days with control unpulsed DCreg (n = 2), to 56 days with donor Ag-pulsed DCreg (n = 5) was associated with evidence of modulated host CD4+ and CD8+ T cell responses to donor Ag and attenuation of systemic IL-17 production. Circulating anti-donor antibody (Ab) was not detected until CTLA4 Ig withdrawal. One monkey treated with donor Ag-pulsed DCreg rejected its graft in association with progressively elevated anti-donor Ab, 525 days posttransplant (160 days after withdrawal of immunosuppression). These findings indicate a modest but not statistically significant beneficial effect of donor Ag-pulsed autologous DCreg infusion on NHP graft survival when administered with a minimal immunosuppressive drug regimen.


Assuntos
Células Dendríticas/imunologia , Sobrevivência de Enxerto/imunologia , Isoantígenos/imunologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Linfócitos T/imunologia , Doadores de Tecidos , Animais , Leucócitos Mononucleares , Macaca mulatta , Masculino , Tolerância ao Transplante , Transplante Homólogo
8.
Br J Anaesth ; 119(4): 616-625, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121280

RESUMO

BACKGROUND: There is growing evidence that beta-blockade may reduce mortality in selected patients with sepsis. However, it is unclear if a pre-existing, chronic oral beta-blocker therapy should be continued or discontinued during the acute phase of severe sepsis and septic shock. METHODS: The present secondary analysis of a prospective observational single centre trial compared patient and treatment characteristics, length of stay and mortality rates between adult patients with severe sepsis or septic shock, in whom chronic beta-blocker therapy was continued or discontinued, respectively. The acute phase was defined as the period ranging from two days before to three days after disease onset. Multivariable Cox regression analysis was performed to compare survival outcomes in patients with pre-existing chronic beta-blockade. RESULTS: A total of 296 patients with severe sepsis or septic shock and pre-existing, chronic oral beta-blocker therapy were included. Chronic beta-blocker medication was discontinued during the acute phase of sepsis in 129 patients and continued in 167 patients. Continuation of beta-blocker therapy was significantly associated with decreased hospital (P=0.03), 28-day (P=0.04) and 90-day mortality rates (40.7% vs 52.7%; P=0.046) in contrast to beta-blocker cessation. The differences in survival functions were validated by a Log-rank test (P=0.01). Multivariable analysis identified the continuation of chronic beta-blocker therapy as an independent predictor of improved survival rates (HR = 0.67, 95%-CI (0.48, 0.95), P=0.03). CONCLUSIONS: Continuing pre-existing chronic beta-blockade might be associated with decreased mortality rates up to 90 days in septic patients.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Sepse/mortalidade , Idoso , Comorbidade , Feminino , Alemanha , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque Séptico/mortalidade , Tempo , Resultado do Tratamento
9.
Am J Transplant ; 15(6): 1472-4, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25846743

RESUMO

Increasing evidence indicates the existence of a complex cross-regulation between the most important biosensors of the human body: The immune and nervous systems. Cytokines control body temperature and trigger autoimmune disorders in the central nervous system, whereas neuropeptides released in peripheral tissues and lymphoid organs modulate inflammatory (innate) and adaptive immune responses. Surprisingly, the effects of nerve fibers and the antidromic release of its pro-inflammatory neuropeptides on the leukocytes of the immune system that mediate graft rejection are practically unknown. In the transplantation field, such area of research remains practically unexplored. A recent study by Riol-Blanco et al has revealed new details on how nociceptive nerves regulate the pro-inflammatory function of leukocytes in peripheral tissues. Although the mechanism(s) by which neuroinflammation affects the immune response against the allograft remains unknown, recent data suggest that this new area of research is worth exploring for potential development of novel complementary therapies for prevention/treatment of graft rejection.


Assuntos
Pesquisa Biomédica/tendências , Sistema Imunitário/fisiologia , Nociceptores/fisiologia , Transplante de Órgãos , Aloenxertos/imunologia , Aloenxertos/fisiologia , Animais , Citocinas/fisiologia , Rejeição de Enxerto/fisiopatologia , Rejeição de Enxerto/prevenção & controle , Humanos , Modelos Animais
10.
Br J Anaesth ; 114(5): 746-56, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25652947

RESUMO

BACKGROUND: Inodilators are commonly used in critically ill patients, but their effect on survival has not been properly studied to date. The objective of this work was to conduct a network meta-analysis on the effects of inodilators on survival in adult cardiac surgery patients, and to compare and rank drugs that have not been adequately compared in head-to-head trials. METHODS: Relevant studies were independently searched in BioMedCentral, MEDLINE/PubMed, Embase, and the Cochrane Central Register of clinical trials (updated on May 1, 2014). The criteria for inclusion were: random allocation to treatment with at least one group receiving dobutamine, enoximone, levosimendan, or milrinone and at least another group receiving the above inodilators or placebo, performed in cardiac surgical patients. The endpoint was to identify differences in mortality at longest follow-up available. RESULTS: The 46 included trials were published between 1995 and 2014 and randomised 2647 patients. The Bayesian network meta-analysis found that only the use of levosimendan was associated with a decrease in mortality when compared with placebo (posterior mean of OR=0.48, 95% CrI 0.28 to 0.80). The posterior distribution of the probability for each inodilator to be the best and the worst drug showed that levosimendan is the best agent to improve survival after cardiac surgery. The sensitivity analyses performed did not produce different interpretative result. CONCLUSION: Levosimendan seems to be the most efficacious inodilator to improve survival in cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Vasodilatadores/farmacologia , Teorema de Bayes , Estado Terminal/mortalidade , Dobutamina/farmacologia , Enoximona/farmacologia , Humanos , Hidrazonas/farmacologia , Milrinona/farmacologia , Piridazinas/farmacologia , Simendana
11.
Prostate ; 74(1): 10-28, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24037776

RESUMO

BACKGROUND: BPH and LUTS have been associated to obesity, hypogonadism, and metabolic syndrome (MetS). MetS-induced prostate and bladder alterations, including inflammation and tissue remodeling, have been related to a low-testosterone and high-estrogen milieu. In addition to ERs, GPR30/GPER is able to mediate several estrogenic non-genomic actions. METHODS: Supplementing a subgroup of MetS rabbits with tamoxifen, we analyzed the in vivo effects on MetS-induced prostate and bladder alterations. The effects of selective ER/GPER ligands and GPER silencing on prostate inflammation were also studied in vitro using hBPH cells. RESULTS: ERα, ERß, and PR expression was upregulated in MetS bladder, where tamoxifen decreased ERα and PR expression, further stimulating ERß. In addition, tamoxifen-dosing decreased MetS-induced overexpression of inflammatory and tissue remodeling genes. In prostate, sex steroid receptors, pro-inflammatory and pro-fibrotic genes were upregulated in MetS. However, tamoxifen did not affect them and even increased COX-2. In hBPH cells, 17ß-estradiol increased IL-8 secretion, an effect blunted by co-treatment with GPER antagonist G15 but not by ER antagonist ICI 182,780, which further increased it. GPER agonist G1 dose-dependently (IC50 = 1.6 nM) induced IL-8 secretion. In vitro analysis demonstrated that GPER silencing reverted these stimulatory effects. CONCLUSIONS: GPER can be considered the main mediator of estrogen action in prostate, whereas in bladder the mechanism appears to rely on ERα, as indicated by in vivo experiments with tamoxifen dosing. Limiting the effects of the MetS-induced estrogen action via GPER could offer new perspectives in the management of BPH/LUTS, whereas tamoxifen dosing showed potential benefits in bladder.


Assuntos
Síndrome Metabólica/metabolismo , Próstata/metabolismo , Receptores de Estrogênio/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologia , Bexiga Urinária/metabolismo , Animais , Linhagem Celular , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 8/genética , Humanos , Masculino , Síndrome Metabólica/tratamento farmacológico , Ligação do Par , Próstata/efeitos dos fármacos , Coelhos , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/uso terapêutico , Bexiga Urinária/efeitos dos fármacos
12.
Am J Transplant ; 13(8): 1989-2005, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23758811

RESUMO

We examined the influence of regulatory dendritic cells (DCreg), generated from cytokine-mobilized donor blood monocytes in vitamin D3 and IL-10, on renal allograft survival in a clinically relevant rhesus macaque model. DCreg expressed low MHC class II and costimulatory molecules, but comparatively high levels of programmed death ligand-1 (B7-H1), and were resistant to pro-inflammatory cytokine-induced maturation. They were infused intravenously (3.5-10 × 10(6) /kg), together with the B7-CD28 costimulation blocking agent CTLA4Ig, 7 days before renal transplantation. CTLA4Ig was given for up to 8 weeks and rapamycin, started on Day -2, was maintained with tapering of blood levels until full withdrawal at 6 months. Median graft survival time was 39.5 days in control monkeys (no DC infusion; n = 6) and 113.5 days (p < 0.05) in DCreg-treated animals (n = 6). No adverse events were associated with DCreg infusion, and there was no evidence of induction of host sensitization based on circulating donor-specific alloantibody levels. Immunologic monitoring also revealed regulation of donor-reactive memory CD95(+) T cells and reduced memory/regulatory T cell ratios in DCreg-treated monkeys compared with controls. Termination allograft histology showed moderate combined T cell- and Ab-mediated rejection in both groups. These findings justify further preclinical evaluation of DCreg therapy and their therapeutic potential in organ transplantation.


Assuntos
Células Dendríticas/transplante , Sobrevivência de Enxerto/imunologia , Tolerância Imunológica/imunologia , Memória Imunológica/imunologia , Nefropatias/prevenção & controle , Transplante de Rim/imunologia , Linfócitos T Reguladores/imunologia , Abatacepte , Animais , Terapia Combinada , Células Dendríticas/citologia , Células Dendríticas/imunologia , Imunoconjugados/imunologia , Imunossupressores/uso terapêutico , Nefropatias/imunologia , Macaca mulatta , Masculino , Sirolimo/uso terapêutico , Transplante Homólogo
13.
Am J Transplant ; 12(6): 1398-408, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22500950

RESUMO

A critical goal in transplantation is the achievement of donor-specific tolerance, minimizing the use of immunosuppressants. Dendritic cells (DCs) are antigen (Ag) presenting cells (APCs) with capability to promote immunity or tolerance. The immune-regulatory properties of DCs have been exploited for generation of tolerogenic/immunosuppressive (IS) DCs that, when transfer systemically, prolong allograft survival in murine models. Surprisingly, the in vivo mechanisms of therapies based on (donor- or recipient-derived) ISDCs in transplantation remain unknown, given that previous studies investigated their effects in vitro, or ex vivo after transplantation. Since once injected, ISDCs are short-lived and transfer Ag to recipient APCs, we assessed the role of recipient DCs by depleting them at the time of ISDC-therapy in a mouse model of cardiac transplantation. The results indicate that, contrary to the accepted paradigm, systemically administered ISDCs reduce the alloresponse and prolong allograft survival, not by themselves, but through conventional DCs (cDCs) of the recipient. These findings raise doubts on the advantages of the currently used ISDC-therapies, since the immune-regulatory properties of the injected ISDC do not seem to be functionally relevant in vivo, and the quiescent/pro-tolerogenic status of cDCs may be compromised in patients with end-stage diseases that require transplantation.


Assuntos
Células Dendríticas , Transplante , Transferência Adotiva , Animais , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunossupressores/administração & dosagem , Camundongos , Camundongos Endogâmicos
14.
Mol Hum Reprod ; 18(8): 417-24, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22383544

RESUMO

The largest gene cluster of human microRNAs (miRNAs), the chromosome 19 miRNA cluster (C19MC), is exclusively expressed in the placenta and in undifferentiated cells. The precise expression pattern and function of C19MC members are unknown. We sought to profile the relative expression of C19MC miRNAs in primary human trophoblast (PHT) cells and exosomes. Using high-throughput profiling, confirmed by PCR, we found that C19MC miRNAs are among the most abundant miRNAs in term human trophoblasts. Hypoxic stress selectively reduced miR-520c-3p expression at certain time-points with no effect on other C19MC miRNAs. Similarly, differentiation in vitro had a negligible effect on C19MC miRNAs. We found that C19MC miRNAs are the predominant miRNA species expressed in exosomes released from PHT, resembling the profile of trophoblastic cellular miRNA. Predictably, we detected the similar levels of circulating C19MC miRNAs in the serum of healthy pregnant women at term and in women with pregnancies complicated by fetal growth restriction. Our data define the relative expression levels of C19MC miRNAs in trophoblasts and exosomes, and suggest that C19MC miRNAs function in placental-maternal signaling.


Assuntos
Cromossomos Humanos Par 19/genética , Exossomos/metabolismo , MicroRNAs/biossíntese , MicroRNAs/genética , Trofoblastos/metabolismo , Adulto , Diferenciação Celular , Células Cultivadas , Feminino , Retardo do Crescimento Fetal/genética , Humanos , MicroRNAs/sangue , Placenta/citologia , Gravidez , Complicações na Gravidez/genética , Terceiro Trimestre da Gravidez
15.
J Geophys Res Solid Earth ; 127(5): e2021JB023488, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35865146

RESUMO

We present the first three-dimensional (3D) anisotropic teleseismic P-wave tomography model of the upper mantle covering the entire Central Mediterranean. Compared to isotropic tomography, it is found that including the magnitude, azimuth, and, importantly, dip of seismic anisotropy in our inversions simplifies isotropic heterogeneity by reducing the magnitude of slow anomalies while yielding anisotropy patterns that are consistent with regional tectonics. The isotropic component of our preferred tomography model is dominated by numerous fast anomalies associated with retreating, stagnant, and detached slab segments. In contrast, relatively slower mantle structure is related to slab windows and the opening of back-arc basins. To better understand the complexities in slab geometry and their relationship to surface geological phenomenon, we present a 3D reconstruction of the main Central Mediterranean slabs down to 700 km based on our anisotropic model. P-wave seismic anisotropy is widespread in the Central Mediterranean upper mantle and is strongest at 200-300 km depth. The anisotropy patterns are interpreted as the result of asthenospheric material flowing primarily horizontally around the main slabs in response to pressure exerted by their mid-to-late Cenezoic horizontal motion, while sub-vertical anisotropy possibly reflects asthenospheric entrainment by descending lithosphere. Our results highlight the importance of anisotropic P-wave imaging for better constraining regional upper mantle geodynamics.

17.
Nanotechnology ; 22(26): 265303, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21576790

RESUMO

We studied a suitable route to fabricate ferroelectric islands by focused-ion-beam milling in bismuth ferrite epitaxial thin films. Piezoresponse force microscopy shows that the damage induced by the milling process is extended to 1 µm away from the edge of the focused-ion-beam patterned islands. After a combined vacuum and oxygen atmosphere annealing procedure, ferroelectricity is fully recovered in structures with sizes down to 500 nm, while for 250 nm islands the defects at the interfaces induce polarization direction pinning.

18.
J Endocrinol Invest ; 34(7): 557-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21720206

RESUMO

BACKGROUND: The relationship between metabolic syndrome (MetS), male hypogonadism and their possible interaction in cardiovascular (CV) risk stratification are not completely understood. AIM: We reviewed relationships between testosterone (T) and MetS emphasizing their possible interaction in the pathogenesis of CV diseases. MATERIALS AND METHODS: A systematic search of published evidence was performed using Medline (1969 to January 2011). RESULTS: Cross-sectional data have shown that subjects with MetS have lower levels of total T (TT) (about 3 nmol/l), as hypogonadism is more evident in subjects with than in those without erectile dysfunction (ED) than in those without. Longitudinal evidence shows that low T is allocated with a higher risk of subsequent development of MetS, although the reverse condition is also possible. Which are the factors in MetS responsible for the low T is not completely clarified. In clinical studies, increased waist circumference is the major determinant of MetS-associated hypogonadism. Our experiments in rabbits do not support the idea that visceral fat is the main determinant of MetS-associated male hypogonadism. Only few randomized clinical trials have evaluated the impact of T replacement therapy (TRT) in patients with MetS. Available evidence suggests that TRT decreases visceral fat accumulation and ameliorates insulin sensitivity, whereas androgen deprivation increases abdominal adiposity. CONCLUSIONS: The clinical significance of the MetS-associated hypogonadism needs further clarifications. In particular, it has not been completely clarified if low T might be considered a cause or a consequence of MetS. The benefit of TRT in term of the reduction of CV risk needs to be confirmed in larger and longer studies.


Assuntos
Hipogonadismo/fisiopatologia , Síndrome Metabólica/fisiopatologia , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Ensaios Clínicos como Assunto , Disfunção Erétil/complicações , Disfunção Erétil/fisiopatologia , Humanos , Hipogonadismo/complicações , Estimativa de Kaplan-Meier , MEDLINE , Masculino , Síndrome Metabólica/complicações , Fatores de Risco , Testosterona/metabolismo
19.
Nat Commun ; 12(1): 7307, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911961

RESUMO

The flow of the Greenland Ice Sheet is controlled by subglacial processes and conditions that depend on the geological provenance and temperature of the crust beneath it, neither of which are adequately known. Here we present a seismic velocity model of the uppermost 5 km of the Greenlandic crust. We show that slow velocities in the upper crust tend to be associated with major outlet glaciers along the ice-sheet margin, and elevated geothermal heat flux along the Iceland hotspot track inland. Outlet glaciers particularly susceptible to basal slip over deformable subglacial sediments include Jakobshavn, Helheim and Kangerdlussuaq, while geothermal warming and softening of basal ice may affect the onset of faster ice flow at Petermann Glacier and the Northeast Greenland Ice Stream. Interactions with the solid earth therefore control the past, present and future dynamics of the Greenland Ice Sheet and must be adequately explored and implemented in ice sheet models.

20.
Int J Androl ; 33(3): 475-88, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19508330

RESUMO

Benign prostatic hyperplasia (BPH) is a common disorder affecting 50-80% of the aged male population. Androgens and age have been traditionally considered the main determinants of prostate enlargement, but in the last years a potentially important role of chronic inflammation in BPH pathogenesis has emerged. Bacterial and non-infectious chronic prostatitis could represent inciting factors leading to tissue hyperproliferation, possibly via the recently demonstrated antigen-presenting capacity of prostatic stromal cells, enabling them to induce and sustain intraglandular immune responses. The prostate growth-promoting chemokine IL-8 could represent a direct link between chronic prostate inflammation and autocrine/paracrine stromal cell proliferation, in agreement with its marked secretion induced in BPH stromal cells by a combination of Th1 and Th17 cell-derived inflammatory cytokines. BPH stromal cells express the vitamin D receptor (VDR), which is up-regulated by exposure to inflammatory stimuli. The non-hypercalcaemic VDR agonist elocalcitol, shown to arrest BPH development by decreasing the intra-prostatic androgen signalling without directly interfering with systemic androgen action, exerts immunoregulatory and anti-inflammatory properties in different prostatic pathology characterized by growth and inflammation. The mechanism of action of VDR agonists supports an important role of chronic inflammation in BPH pathogenesis and strengthens the concept of these agents as a therapeutic option for pharmacological treatment of BPH.


Assuntos
Inflamação/imunologia , Hiperplasia Prostática , Androgênios/fisiologia , Androgênios/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Calcitriol/análogos & derivados , Quimiocinas/uso terapêutico , Doença Crônica , Citocinas/imunologia , Citocinas/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Interleucina-8/uso terapêutico , Masculino , Próstata/metabolismo , Próstata/patologia , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/etiologia , Hiperplasia Prostática/patologia , Prostatite/complicações , Prostatite/tratamento farmacológico , Prostatite/patologia , Receptores de Calcitriol/agonistas , Receptores de Calcitriol/metabolismo , Transdução de Sinais , Células Estromais/metabolismo , Células Estromais/patologia
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