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1.
Soft Matter ; 17(41): 9353-9362, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34604893

RESUMO

Nanogels play a leading role in controlled release systems because they possess high water retention capacity resulting in high loading capabilities, stability in biological fluids and biocompatibility. In this scenario, every tool that allows extending the nanogel properties and expanding their potential applications is of high interest in the field of biomedicine. This article aims to contribute to the development of multifunctional nanogels, based on the combination of two polymer phases in a multilobular morphology. The synthesized multilobed nanogels (mLNGs) presented a core of crosslinked poly(N-vinylcaprolactam) (PVCL) and a shell formed by 3-D distributed lobes of a low Tg copolymer. This particular multilobular morphology is able to exploit the synergetic contribution of both phases. While the PVCL-based core conferred its characteristic thermal response and the ability to load and release a cargo molecule, the low Tg lobes incorporated the capability of film formation. Moreover, the multilobular arrangement of NGs allows films to undergo unrestricted mass transfer. The development of mLNG morphology and the effect of synthesis parameters were deeply studied with the help of a previously developed mathematical model for the dynamic evolution of particle morphology. Finally, this study presents, for the first time, the synthesis of two-phase nanogels with multilobular morphology and underlines their potential as a candidate for controlled delivery platforms.

2.
Phys Rev Lett ; 122(4): 042502, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768318

RESUMO

Even mass neutron-rich niobium isotopes are among the principal contributors to the reactor antineutrino energy spectrum. They are also among the most challenging to measure due to the refractory nature of niobium, and because they exhibit isomeric states lying very close in energy. The ß-intensity distributions of ^{100gs,100m}Nb and ^{102gs,102m}Nb ß decays have been determined using the total absorption γ-ray spectroscopy technique. The measurements were performed at the upgraded Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. Here, the double Penning trap system JYFLTRAP was employed to disentangle the ß decay of the isomeric states. The new data obtained in this challenging measurement have a large impact in antineutrino summation calculations. For the first time the discrepancy between the summation model and the reactor antineutrino measurements in the region of the shape distortion has been reduced.

3.
Phys Rev Lett ; 120(2): 022503, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376701

RESUMO

We investigate the recent Daya Bay results on the changes in the antineutrino flux and spectrum with the burnup of the reactor fuel. We find that the discrepancy between current model predictions and the Daya Bay results can be traced to the original measured ^{235}U/^{239}Pu ratio of the fission ß spectra that were used as a base for the expected antineutrino fluxes. An analysis of the antineutrino spectra that is based on a summation over all fission fragment ß decays, using nuclear database input, explains all of the features seen in the Daya Bay evolution data. However, this summation method still allows for an anomaly. We conclude that there is currently not enough information to use the antineutrino flux changes to rule out the possible existence of sterile neutrinos.

4.
Phys Rev Lett ; 119(11): 112501, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28949211

RESUMO

Current predictions for the antineutrino yield and spectra from a nuclear reactor rely on the experimental electron spectra from ^{235}U, ^{239}Pu, ^{241}Pu and a numerical method to convert these aggregate electron spectra into their corresponding antineutrino ones. In the present work we investigate quantitatively some of the basic assumptions and approximations used in the conversion method, studying first the compatibility between two recent approaches for calculating electron and antineutrino spectra. We then explore different possibilities for the disagreement between the measured Daya Bay and the Huber-Mueller antineutrino spectra, including the ^{238}U contribution as well as the effective charge and the allowed shape assumption used in the conversion method. We observe that including a shape correction of about +6% MeV^{-1} in conversion calculations can better describe the Daya Bay spectrum. Because of a lack of experimental data, this correction cannot be ruled out, concluding that in order to confirm the existence of the reactor neutrino anomaly, or even quantify it, precisely measured electron spectra for about 50 relevant fission products are needed. With the advent of new rare ion facilities, the measurement of shape factors for these nuclides, for many of which precise beta intensity data from TAGS experiments already exist, would be highly desirable.

5.
Phys Rev Lett ; 116(13): 132502, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27081973

RESUMO

Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 ^{235}U fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of ^{86}Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel.

6.
Phys Rev Lett ; 115(6): 062502, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26296113

RESUMO

Total absorption spectroscopy is used to investigate the ß-decay intensity to states above the neutron separation energy followed by γ-ray emission in (87,88)Br and (94)Rb. Accurate results are obtained thanks to a careful control of systematic errors. An unexpectedly large γ intensity is observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy is compared to Hauser-Feshbach model calculations. For (87)Br and (88)Br the γ branching reaches 57% and 20%, respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich (94)Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled by introducing an enhancement of 1 order of magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proves to be correct, leads to a similar increase in the (n,γ) cross section that would have an impact on r process abundance calculations.

7.
Phys Rev Lett ; 115(10): 102503, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382674

RESUMO

The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. (92)Rb makes the dominant contribution to the reactor antineutrino spectrum in the 5-8 MeV range but its decay properties are in question. We have studied (92)Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.

8.
J Pediatr Gastroenterol Nutr ; 60(2): 159-64, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25304891

RESUMO

OBJECTIVE: Autoimmune hepatitis (AIH) is considered an underdiagnosed cause of fulminant hepatic failure (FHF). Autoimmune FHF (AI-FHF) is believed to lead invariably to liver transplantation (LTX) or death. We aimed to describe the autoimmune features of children diagnosed as having AI-FHF and indeterminate FHF (ID-FHF), and describe the outcome of patients with AI-FHF treated with immunosuppressive drugs. METHODS: In this case-control study, the files of patients with AI-FHF and ID-FHF were reviewed and compared. AIH was diagnosed based on positive autoantibodies, raised immunoglobulin G, and histology when available. FHF was defined by raised transaminases, international normalised ratio ≥ 2.0, presence of encephalopathy, and no previously recognised liver disease. RESULTS: A total of 46 children with FHF were managed in the last 15 years: 10/46 (22%) had AI-FHF, 20/46 (43%) ID-FHF, and 16 had other diagnosis. The mean follow-up time was 4.6 years. AI-FHF and ID-FHF differed for the presence of autoantibodies (10/10, 6/10 liver/kidney microsome [LKM]-type, vs 3/20, none LKM, P < 0.0001), immunoglobulin G level (1845 vs 880 mg/dL, P < 0.001), median age at diagnosis (6.4 vs 1.8 years, P = 0.017), and alanine aminotransferase level (1020 vs 2386 IU/L, P = 0.029). Liver histology did not allow to differentiate the 2 conditions. Among the patients with AI-FHF, 4/9 who received steroids recovered; 5/9 required LTX and 1 died awaiting treatment. CONCLUSIONS: AIH is a much more common cause of FHF than previously suggested, and a complete autoantibody testing including LKM-type is essential in this setting. Autoantibodies are uncommon in ID-FHF, and histology cannot distinguish it from AI-FHF. A cautious steroid trial may avoid LTX in some of the patients with AI-FHF.


Assuntos
Hepatite Autoimune/complicações , Imunossupressores/uso terapêutico , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/terapia , Adolescente , Fatores Etários , Alanina Transaminase/sangue , Anticorpos Antinucleares/sangue , Autoanticorpos/sangue , Azatioprina/uso terapêutico , Estudos de Casos e Controles , Criança , Pré-Escolar , Ciclosporina/uso terapêutico , Seguimentos , Humanos , Imunoglobulina G/sangue , Lactente , Falência Hepática Aguda/patologia , Transplante de Fígado , Metilprednisolona/uso terapêutico , Estudos Retrospectivos , Taxa de Sobrevida
9.
Eur J Radiol ; 137: 109613, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33657476

RESUMO

PURPOSE: Pulmonary embolism (PE) in COVID-19 patients can play a key role in precipitating clinical conditions. We aimed to evaluate PE distribution on CTA and to investigate any possible association with D-dimer (DD), pulmonary stage of disease and prognosis. METHOD: COVID-19 patients of two affiliated Hospitals, undergone a CTA examination for PE suspicion, were retrospectively enrolled. Comorbidities, laboratory tests and clinical outcomes (hospitalization, discharge, death) were assessed. A parenchymal stage (early, progressive, peak, absorption) for lung involvement was assigned. RESULTS: A cohort of 114 patients (mean age 61 years; 26.3 % females) with severe COVID-19 pneumonia were evaluated. At last follow-up 25 (21.9 %) were hospitalized, 72 (63.2 %) discharged, 17 (14.9 %) dead. Eighty-eight patients (77.2 %) had at least one comorbidity, being cardiovascular ones the most frequent (44.7 %). CTA revealed PE in 65 patients (57 %), with concomitant pulmonary trunk and/or main arteries involvement in 16.9 %. PE defects were ubiquitous in 18.5 % of cases. The predominant parenchymal stages were the progressive (24.6 %) and peak (67.7 %). DD levels showed a significant correlation with PE occurrence and extent in pulmonary branches, despite anticoagulant therapies; trend of correlation with pulmonary stages was also noted. CONCLUSIONS: PE is a frequent complication in severe COVID-19 patients, particularly during central parenchymal stages and despite ongoing anticoagulant therapy. CTA and DD levels play a crucial role in the assessment of suspected PE, despite anticoagulant therapies, along with proper information about lung involvement extent.


Assuntos
COVID-19 , Embolia Pulmonar , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
10.
Ann Oncol ; 21(2): 245-254, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19633051

RESUMO

BACKGROUND: Peritumoral vascular invasion (PVI) may assist in assigning optimal adjuvant systemic therapy for women with early breast cancer. PATIENTS AND METHODS: Patients participated in two International Breast Cancer Study Group randomized trials testing chemoendocrine adjuvant therapies in premenopausal (trial VIII) or postmenopausal (trial IX) node-negative breast cancer. PVI was assessed by institutional pathologists and/or central review on hematoxylin-eosin-stained slides in 99% of patients (analysis cohort 2754 patients, median follow-up >9 years). RESULTS: PVI, present in 23% of the tumors, was associated with higher grade tumors and larger tumor size (trial IX only). Presence of PVI increased locoregional and distant recurrence and was significantly associated with poorer disease-free survival. The adverse prognostic impact of PVI in trial VIII was limited to premenopausal patients with endocrine-responsive tumors randomized to therapies not containing goserelin, and conversely the beneficial effect of goserelin was limited to patients whose tumors showed PVI. In trial IX, all patients received tamoxifen: the adverse prognostic impact of PVI was limited to patients with receptor-negative tumors regardless of chemotherapy. CONCLUSION: Adequate endocrine adjuvant therapy appears to abrogate the adverse impact of PVI in node-negative disease, while PVI may identify patients who will benefit particularly from adjuvant therapy.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Quimioterapia Adjuvante/métodos , Ciclofosfamida/uso terapêutico , Progressão da Doença , Feminino , Fluoruracila/uso terapêutico , Gosserrelina/uso terapêutico , Humanos , Menopausa/fisiologia , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Invasividade Neoplásica , Neovascularização Patológica/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Resultado do Tratamento
11.
Phys Rev Lett ; 105(20): 202501, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-21231223

RESUMO

The ß feeding probability of (102,104,105,106,107)Tc, 105Mo, and 101Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the γ component of the decay heat for 239Pu in the 4-3000 s range.

13.
Surg Endosc ; 24(11): 2888-94, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20526623

RESUMO

BACKGROUND: We assessed feasibility, short-term oncologic safety, and short-term outcomes in robotic total mesorectal excision (R-TME) for rectal cancer compared with laparoscopic TME. METHODS: From March 2008 to June 2009, 50 patients with proven middle/lower rectal adenocarcinoma underwent minimally invasive TME; 25 received R-TME. The groups were balanced (R-TME versus L-TME) in terms of age (median 69 versus 62 years; p = 0.8), disease stage, and body mass index (median 23 versus 26.5 kg/m(2); p = 0.06). There were 37 (74%) anterior resections and 13 (26%) abdominoperineal resections. Twenty-three (46%) patients received preoperative radiochemotherapy. The robot was a four-arm Da Vinci S (Intuitive Surgical, Sunnyvale, CA, USA). RESULTS: Median operating time (R-TME versus L-TME) was 240 versus 237 min (p = 0.2); first bowel movement was 2 versus 3 days (p = 0.5); median hospital stay was 6.5 versus 6 days (p = 0.4). Major complications with reoperation were two in R-TME (one anastomotic leakage, one small bowel perforation) and three in L-TME (one colonic ischemia, two anastomotic leakage). Postoperative complications were 16% versus 24% (p = 0.5). A median of 18 versus 17 (p = 0.7) lymph nodes were retrieved; distal resection margins were disease free in both groups; circumferential margin was involved (<1.0 mm) in one (4%) of L-TME. There were 0 versus 1 (5%) conversions to laparotomy. CONCLUSIONS: R-TME in rectal cancer is feasible, with short-term oncologic and other outcomes similar to those of L-TME. The greater maneuverability and visibility afforded by the robotic approach are attractive. Future studies should more systematically address advantages and costs of R-TME.


Assuntos
Adenocarcinoma/cirurgia , Laparoscopia , Neoplasias Retais/cirurgia , Reto/cirurgia , Robótica , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Complicações Intraoperatórias , Laparoscopia/efeitos adversos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Neoplasias Retais/patologia
14.
Gut ; 58(11): 1481-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19570762

RESUMO

OBJECTIVE: In mice, a subpopulation of gut dendritic cells (DCs) expressing CD103 drives the development of regulatory T (T(reg)) cells. Further, it was recently described that the cross-talk between human intestinal epithelial cells (IECs) and DCs helps in maintaining gut immune homeostasis via the induction of non-inflammatory DCs. In this study, an analysis was carried out to determine whether IECs could promote the differentiation of CD103+ tolerogenic DCs, and the function of primary CD103+ DCs isolated from human mesenteric lymph nodes (MLNs) was evaluated. METHODS: Monocyte-derived DCs (MoDCs) and circulating CD1c+ DCs were conditioned or not with supernatants from Caco-2 cells or IECs isolated from healthy donors or donors with Crohn's disease and analysed for their ability to induce T(reg) cell differentiation. In some cases, transforming growth factor beta (TGFbeta), retinoic acid (RA) or thymic stromal lymphopoietin (TSLP) were neutralised before conditioning. CD103+ and CD103- DCs were sorted by fluorescence-activated cell sorting (FACS) from MLNs and used in T(reg) cell differentiation experiments. RESULTS: It was found that human IECs promoted the differentiation of tolerogenic DCs able to drive the development of adaptive Foxp3+ T(reg) cells. This control was lost in patients with Crohn's disease and paralleled a reduced expression of tolerogenic factors by primary IECs. MoDCs differentiated with RA or IEC supernatant upregulated the expression of CD103. Consistently, human primary CD103+ DCs isolated from MLNs were endowed with the ability to drive T(reg) cell differentiation. This subset of DCs expressed CCR7 and probably represents a lamina propria-derived migratory population. CONCLUSIONS: A population of tolerogenic CD103+ DCs was identified in the human gut that probably differentiate in response to IEC-derived factors and drive T(reg) cell development.


Assuntos
Diferenciação Celular , Células Dendríticas/citologia , Intestinos/citologia , Linfócitos T Reguladores/citologia , Antígenos CD/metabolismo , Células CACO-2/citologia , Doença de Crohn/imunologia , Doença de Crohn/patologia , Células Dendríticas/imunologia , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Humanos , Imunidade Celular , Cadeias alfa de Integrinas/metabolismo , Linfonodos/citologia , Ativação Linfocitária/imunologia
15.
Hepatol Int ; 13(4): 510-518, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31069759

RESUMO

OBJECTIVES AND STUDY: Various degrees of biliary changes are considered to be part of the histological picture of children with pediatrics autoimmune liver disease (AILD), but the literature is scarce and confusing. We aimed to describe the characteristics of children with AILD (autoimmune hepatitis, AIH, and autoimmune sclerosing cholangitis, ASC) focusing on the prevalence and type of biliary abnormalities on initial biopsy to see whether ASC was predictable on histological ground. METHODS: The files of children diagnosed with AILD were reviewed. The Ishak score was used to grade inflammation and fibrosis on biopsy; a biliary score was built to grade bile duct injury. Demographic, laboratory and histological features at diagnosis were reported and compared between the two groups (AIH vs ASC). RESULTS: Forty-one patients were diagnosed with AIH (n = 24), ASC (n = 13) and PSC (n = 4) between 2009 and 2018. Twenty-nine patients [F = 76%, AIH = 20, ASC = 9, median age at diagnosis 11.7 (range 2.2-17.8)] were included in the study; 12 (4 with PSC) were excluded. Prevalence of inflammatory bowel disease was higher in ASC group (56% vs 10% in AIH, p < 0.05). On histology 17% had cirrhosis. The grade of biliopathy with AILD was moderate in 72% and severe in 31%, and overall more prominent in ASC (p = 0.031). The inflammation of the bile ducts was classified as "multifocal" or "diffuse" mainly in ASC patients (89% vs 45% in AIH, p = 0.043). Periductular fibrosis was reported in 52% of AILD patients, with a higher mean score in ASC group (p < 0.05). However, ductular reaction, biliary metaplasia and granulomatous cholangitis were equally reported in AIH and ASC, providing no clear-cut for the distinction of the two entities in the global histological evaluation. CONCLUSIONS: Majority of patients with pediatrics AILD have "moderate" or "severe" features of biliopathy; AIH and ASC are not easily distinguishable on histological ground at diagnosis, and therefore, the cholangiogram remains the only effective tool to differentiate patients with AIH from those with ASC. Further prospective studies are needed to better define histological biliary features in AILD, assess if the biliopathy responds to immunosuppressive treatment and evaluate its impact on long-term outcome.


Assuntos
Colangite Esclerosante/patologia , Colangite/patologia , Hepatite Autoimune/patologia , Adolescente , Azatioprina/administração & dosagem , Criança , Pré-Escolar , Colangite/tratamento farmacológico , Colangite Esclerosante/tratamento farmacológico , Quimioterapia Combinada , Feminino , Hepatite Autoimune/tratamento farmacológico , Humanos , Imunossupressores/administração & dosagem , Cirrose Hepática Biliar/patologia , Linfócitos/patologia , Masculino , Prednisona/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento , Ácido Ursodesoxicólico/administração & dosagem
16.
Ann Oncol ; 18(10): 1632-40, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17716986

RESUMO

BACKGROUND: The clinical relevance of the degree of peritumoral vascular invasion (PVI) in patients with no or limited involvement of the axillary nodes is unknown. MATERIALS AND METHODS: 2606 consecutive patients with pT1-3, pN0 (1586)-1a (1020) and M0, operated and counseled for medical therapy from 1/2000 to 12/2002, were prospectively classified according to the degree of PVI: absent (2017, 77.4%), focal (368, 14.1%), moderate (51, 2.0%) and extensive (170, 6.5%). RESULTS: Patients with extensive PVI were more likely to be younger, to have larger tumors, high tumor grade, axillary-positive nodes, high Ki-67 expression and HER2/neu over-expression compared with patients having less PVI (P for trend, <0.0001). In patients with node-negative disease a statistically significant difference in disease-free survival (DFS), risk of distant metastases and overall survival (OS) was observed at the multivariate analysis for extensive PVI versus no PVI (hazard ratios: 2.11, 95% CI, 1.02 to 4.34, P = 0.04 for DFS; 4.51, 95% CI, 1.96 to 10.4, P< 0.001 for distant metastases; 3.55, 95% CI, 1.24 to 10.1, P = 0.02 for OS). CONCLUSIONS: The extent of vascular invasion should be considered in the therapeutic algorithm in order to properly select targeted adjuvant treatment.


Assuntos
Vasos Sanguíneos/patologia , Neoplasias da Mama/patologia , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Estudos Prospectivos
17.
Dig Liver Dis ; 39(9): 818-23, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17652043

RESUMO

BACKGROUND: Previous studies have demonstrated that serum anti-actin antibodies are a reliable marker of intestinal damage severity in coeliac disease. AIMS: To validate in a multicentre study the clinical usefulness of serum IgA anti-actin antibody ELISA and its possible use in monitoring intestinal mucosa lesions during gluten-free diet. PATIENTS AND METHODS: Four centres recruited 205 newly diagnosed coeliac disease patients with villous atrophy, 80 healthy controls and 81 "disease" controls. Twelve coeliac disease patients on gluten-free diet but with persistent symptoms underwent serum IgA anti-actin antibody assay and intestinal histology evaluation. IgA anti-actin antibody ELISA was performed with a commercial kit. All coeliac disease patients underwent intestinal histology study. RESULTS: IgA anti-actin antibodies showed a sensitivity of 80% and a specificity of 85% in the diagnosis of coeliac disease patients with villous atrophy. The area under the receiving operator curve for anti-actin antibodies was 0.873 [95% C.I. 0.805-0.899]. Serum anti-actin antibodies values were significantly higher in coeliac disease patients than in healthy or "disease" controls (P<0.0001). Serum anti-actin antibodies were positive in 41 of the 60 coeliac disease patients with mild intestinal histology lesions (69%) and in 123 of the 145 with severe lesions (85.3%) (P<0.05). There was a significant inverse correlation between anti-actin antibody values and the villi/crypts ratio (r=-0.423; P<0.0001). In the 12 coeliac disease patients on gluten-free diet who underwent re-evaluation as they were persistently symptomatic, intestinal histology showed three cases with persistent villous atrophy: all of these were positive for serum anti-actin antibodies ELISA, whereas both serum anti-tTG and EmAs were negative. The other nine patients showed normal intestinal villi and were negative for serum anti-actin antibodies. CONCLUSIONS: Anti-actin antibodies are a reliable marker of severe intestinal mucosa damage in coeliac disease patients and a simple ELISA technique offers an accurate method for their determination. These antibodies seem to be a very reliable marker of persistent intestinal damage in coeliac disease patients.


Assuntos
Actinas/imunologia , Autoanticorpos/sangue , Doença Celíaca/diagnóstico , Doença Celíaca/patologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina A/sangue , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Doença Celíaca/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
18.
Eur J Pediatr Surg ; 17(1): 50-4, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17407022

RESUMO

The authors report a very unusual case of intermittent and painful rectal bleeding occurring in a two-year-old female. At proctosigmoidoscopy, a bluish mucosal fold was found in the rectal ampulla. Histological examination showed the presence of heterotopic gastric mucosa islands intermingled with normal rectal mucosa. Surgical transanal excision of the lesion was undertaken due to the persistence of rectal bleeding with anemia, notwithstanding a three-month course of pharmacological therapy with a proton pump inhibitor. At a one-year follow-up, the child is well and symptom-free. The international pediatric literature was reviewed.


Assuntos
Coristoma/diagnóstico , Mucosa Gástrica , Hemorragia Gastrointestinal/etiologia , Doenças Retais/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
19.
Dig Liver Dis ; 49(10): 1139-1145, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28663066

RESUMO

BACKGROUND: Identifying the causes of acute liver failure (ALF) and predictors of death or liver transplantation (LTX) is crucial to decide its management. We aimed to describe features and outcome of ALF in Italian children. METHODS: Retrospective review of cases presenting between 1996-2012. ALF was defined by high transaminases, INR ≥2.0 regardless of hepatic encephalopathy (HE), no evidence of underlying chronic liver disease. RESULTS: 55 children (median age 2.6 years, range 0.1-15.1; M/F=31/24) had ALF due to autoimmune hepatitis (AIH) in 10 (18%), metabolic disorders in 9 (17%), paracetamol overdose in 6 (11%), mushroom poisoning in 3 (5%), viral infection in 1 (2%), indeterminate in 26 (47%); 25/55 recovered with supportive management (45%); 28/55 underwent LTX and 2 died on the waiting list (55%). On multivariate analysis severity of HE grade 3-4 and bilirubin ≥12mg/dl were independent predictors of death or LTX (p<0.05). After a median follow up of 4 years (range 2-15.0 years) the overall survival rate was 93%. CONCLUSION: Children with ALF can be managed successfully with combined medical treatment and transplantation, warranting a survival rate similar to children transplanted because of chronic conditions. In our cohort of patients severe HE and high bilirubin on admission were independent predictors of the need of LTX.


Assuntos
Bilirrubina/sangue , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/terapia , Transplante de Fígado , Índice de Gravidade de Doença , Adolescente , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Coeficiente Internacional Normatizado , Itália , Falência Hepática Aguda/sangue , Falência Hepática Aguda/mortalidade , Masculino , Estudos Retrospectivos , Taxa de Sobrevida , Centros de Atenção Terciária
20.
Transplant Proc ; 38(4): 1099-100, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16757276

RESUMO

BACKGROUND: We report our results with the use of corticosteroid-free immunosuppression after pediatric liver transplantation, evaluating the efficiency and safety of this protocol in the early posttransplantation period. PATIENTS AND METHODS: From July 2003 to October 2005, 34 liver transplantations were performed in 32 pediatric patients (19 boys, 13 girls) at our institution. Recipient median age was 5 years (range, 0.2-14 years), and median body weight was 10 kg (range, 4-49 kg). Twenty-seven patients received a graft from in situ split liver transplantation, 5 a whole graft. Twenty-nine children (90%) received an immunosuppressive therapy based on methylprednisolone IV bolus at reperfusion (10 mg/kg) plus tacrolimus given at an initial dose of 0.08 mg/kg/d and then adjusted to obtain whole blood trough levels of 10 to 15 ng/mL during the first 3 months and 5 to 10 ng/mL after the 3rd month; basiliximab was given on postoperative days 0 and 4. Biopsy-proven acute rejection episodes were treated by methylprednisone IV boluses. RESULTS: After a median follow-up of 9 months (range, 1-27 months), the overall patient survival rate was 84% and graft survival rate was 79%. Three children (9%) died after their transplantations. Three (9%) experienced episodes of biopsy-proven acute rejection, always treated with IV steroid boluses. Mean RAI score was 4. One patient experienced PTLD that resolved with temporary reduction of immunosuppression. Cytomegalovirus infection rate was 14%. Sepsis occurred in 2 cases (6%). CONCLUSIONS: Initial results with a steroid-free immunosuppressive protocol are encouraging, with low rates of acute rejection and infectious complications as in steroid-based protocols.


Assuntos
Corticosteroides , Imunossupressores/uso terapêutico , Transplante de Fígado/imunologia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Transplante de Fígado/métodos , Masculino , Segurança , Fatores de Tempo , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento
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