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1.
ACS Omega ; 9(23): 25034-25041, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38882075

RESUMO

In this study, the functionality of an elastomer composite material containing polypyrrole (PPy) as a stress sensor was evaluated. The material was prepared using the swelling method by diffusing the pyrrole monomer into the elastomer before polymerization. To achieve adequate diffusion, organic solvents with affinity for the elastomer were used. The resulting materials were characterized by scanning electron microscopy (SEM), surface electrical resistance, and thermal and mechanical properties for application as a stress sensor. The simultaneous change in electrical resistance and tension stress was measured using a digital multimeter with electrodes connected to the jaws of a universal mechanical testing machine. The influence of stress cycles on the piezoresistivity of the composite materials was investigated. The obtained PPy/NBR composite presented a good combination of electrical conductivity and mechanical properties. The strain at break remained with mild variation after coating with PPy.

2.
ACS Omega ; 9(8): 9526-9535, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434895

RESUMO

This study addresses the fabrication of extruded films using poly(lactic acid) (PLA) and chitosan, with and without maleic anhydride as a compatibilizing agent, for potential applications in disposable food packaging. These films underwent controlled conditions of UV irradiation, water condensation, and temperature variations in an accelerated weathering chamber. The investigation analyzed the effect of different exposure periods on the structural, morphological, mechanical, and thermal properties of the films. It was observed that PLA films exhibited a lower susceptibility to degradation compared to those containing chitosan. Specifically, the pure PLA film showed an increase in elastic modulus and strength during the initial 144 h of exposure, associated with cross-linking induced by UV radiation. On the other hand, film Q2 composed of PLA, chitosan, and maleic anhydride and Q1 without maleic anhydride experienced a tensile strength loss of over 50% after 244 h of exposure. The Q2 film exhibited greater homogeneity, leading to increased resistance to degradation compared to that of Q1. As the degradation time increased, both the Q1 and Q2 films demonstrated a decline in thermal stability. These films also exhibited alterations in crystallinity attributed to the chemo-crystallization process, along with fluctuations in the glass transition temperature and crystallization, particularly at 288 h.

3.
Angew Chem Int Ed Engl ; 63(5): e202317848, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38087836

RESUMO

When (4n +2) π-electrons are located in single planar ring, it conventionally qualifies as aromatic. According Hückel's rule, systems possessing ten π-electrons should be aromatic. Herein we report a series of D5h  Li6 E5 Li6 sandwich structures, representing the first global minima featuring ten π-electrons E5 10- ring (E=Si-Pb). However, these π-electrons localize as five π-lone-pairs rather than delocalized orbitals. The high symmetry structure achieved is a direct consequence of σ-aromaticity, particularly favored in elements from Si to Pb, resulting in a pronounced diatropic ring current flow that contributes to the enhanced stability of these systems.

4.
Am J Transplant ; 23(4): 577-581, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36725427

RESUMO

The current shortage of pediatric multivisceral donors accounts for the long time and mortality on the waiting list of pediatric patients. The use of donors after cardiac death, especially after the outbreak of normothermic regional perfusion, has increased in recent years for all solid organs except the intestine, mainly because of its higher susceptibility to ischemia-reperfusion injury. We present the first literature case of multivisceral donors after cardiac death transplantation in a 13-month-old recipient from a 2.5-month-old donor. Once exitus was certified, an extracorporeal membrane oxygenation circuit was established, cannulating the aorta and infrarenal vena cava, while the supra-aortic branches were clamped. The abdominal organs completely recovered from ischemia through normothermic regional perfusion (extracorporeal membrane oxygenation initially and beating heart later). After perfusion with the preservation solution, the multivisceral graft was uneventfully implanted. Two months later, the patient was discharged without any complications. This case demonstrates the possibility of reducing the time spent on the waiting list for these patients.


Assuntos
Preservação de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Criança , Lactente , Preservação de Órgãos/efeitos adversos , Doadores de Tecidos , Morte , Coleta de Tecidos e Órgãos , Perfusão
5.
Neurosurgery ; 92(6): 1303-1311, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36762899

RESUMO

BACKGROUND: Congenital obstructive hydrocephalus generates progressive irreversible fetal brain damage by ventricular enlargement and incremental brain tissue compression that leads to maldevelopment and poor clinical outcomes. Intrauterine treatments such as ventriculo-amniotic shunting have been unsuccessfully tried in the eighties. OBJECTIVE: To assess if prenatal endoscopic third ventriculostomy (ETV) is feasible in a large animal model and optimize this technique for ventricular decompression and potential arrest of fetal brain damage in fetal lambs. METHODS: We generated hydrocephalus in 50 fetal lambs by injecting a polymeric agent into the cisterna magna at midgestation (E85). Subsequently, 3 weeks later (E105), fetal ETV was performed using a small rigid fetoscope. The endoscopy entry point was located anterior to the coronal suture, 7 mm from the midline. RESULTS: We obtained clear visualization of the enlarged lateral ventricles by endoscopy in the hydrocephalic fetal lambs. The floor of the third ventricle was bluntly perforated and passed with the scope for a successful ETV. Total success was achieved in 32/50 cases (64%). Causes of failure were blurred vision or third ventricle obliteration by BioGlue in 10/50 (20%) cases, anatomic misdirection of the endoscope in 5 (10%) cases, 2 cases of very narrow foramen of Monro, and 1 case of choroid plexus bleeding. If we exclude the cases artificially blocked by the polymer, we had a successful performance of prenatal-ETV in 80% (32/40) of hydrocephalic fetuses. CONCLUSION: Despite the inherent difficulties arising from ovine brain anatomy, this study shows that innovative fetal ETV is technically feasible in hydrocephalic fetal lambs.


Assuntos
Feto , Hidrocefalia , Neuroendoscopia , Terceiro Ventrículo , Animais , Feto/cirurgia , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Hidrocefalia/veterinária , Neuroendoscopia/métodos , Neuroendoscopia/veterinária , Ovinos , Terceiro Ventrículo/cirurgia , Resultado do Tratamento , Ventriculostomia/métodos , Ventriculostomia/veterinária
6.
Chemphyschem ; 23(19): e202200366, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-35785508

RESUMO

A low-lying structure is revealed for the CuB12 - cluster, which is bowl-shaped. It consists of a triangular CuB2 base and a B10 rim. Molecular dynamics simulations indicates its structural robustness; at an elevated temperature (600 K), the base rotates reversibly within the B10 perimeter. Chemical bonding analysis detects 2σ- and 3π-delocalized bonds, suggesting double aromaticity. This is also confirmed by two diatropic and concentric ring currents under an external magnetic field.

7.
Front Pediatr ; 10: 823180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223699

RESUMO

Recurrence is one of the most common surgical complications in Congenital Diaphragmatic Hernia (CDH). It could remain clinically silent for a long time or present as an acute complication week, months, or even years after the primary surgery. Several risk factors have been identified so far. An extended diaphragmatic defect represents one of the leading independent risk factors, together with indirect signs of large defect such as the liver position related to the diaphragm and the use of the prosthetic patch and with the use of a minimally invasive surgical (MIS) approach. However, the exact contribution of each factor and the overall risk of recurrence during the life span still need to be fully understood. This mini-review aims to give an overview of the current knowledge regarding CDH recurrence, focusing on predisposing factors, clinical presentation, management and follow-up of high-risk patients, and future perspectives.

8.
Molecules ; 28(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36615438

RESUMO

Here, it is shown that the M3B12 (M = Cu-Au) clusters' global minima consist of an elongated planar B12 fragment connected by an in-plane linear M3 fragment. This result is striking since this B12 planar structure is not favored in the bare cluster, nor when one or two metals are added. The minimum energy structures were revealed by screening the potential energy surface using genetic algorithms and density functional theory calculations. Chemical bonding analysis shows that the strong electrostatic interactions with the metal compensate for the high energy spent in the M3 and B12 fragment distortion. Furthermore, metals participate in the delocalized π-bonds, which infers an aromatic character to these species.


Assuntos
Cromatografia Gasosa , Eletricidade Estática
9.
Clin Transplant ; 35(4): e14226, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33465824

RESUMO

BACKGROUND: Mesenchymal stromal cells (MSC) have been proposed as a promising complement to standard immunosuppression in solid organ transplantation because of their immunomodulatory properties. The present work addresses the role of adipose-derived MSC (Ad-MSC) in an experimental model of acute rejection in small bowel transplantation (SBT). MATERIAL/METHODS: Heterotopic allogeneic SBT was performed. A single dose of 1.5x106 Ad-MSC was intra-arterially delivered just before graft reperfusion. Animals were divided into CONTROL (CTRL), CONTROL+Ad-MSC (CTRL_MSC), tacrolimus (TAC), and TAC+Ad-MSC (TAC_MSC) groups. Each Ad-MSC groups was subdivided in autologous and allogeneic third-party groups. RESULTS: Rejection rate and severity were similar in MSC-treated and untreated animals. CTRL_MSC animals showed a decrease in macrophages, T-cell (CD4, CD8, and Foxp3 subsets) and B-cell counts in the graft compared with CTRL, this decrease was attenuated in TAC_MSC animals. Pro- and anti-inflammatory cytokines and some chemokines and growth factors increased in CTRL_MSC animals, especially in the allogeneic group, whereas milder changes were seen in the TAC groups. CONCLUSION: Ad-MSC did not prevent rejection when administered just before reperfusion. However, they showed immunomodulatory effects that could be relevant for a longer-term outcome. Interference between tacrolimus and the MSC effects should be addressed in further studies.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Estudos de Viabilidade , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Humanos , Terapia de Imunossupressão
10.
J Clin Med ; 9(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33255911

RESUMO

The Distress Risk Assessment Method (DRAM) was presented by Main, Wood and Hillis in 1992 as a simple means of assessing the risk of failure due to psychosocial factors in spine surgery. To our knowledge, it has not been used in our setting. The aim of this study was to analyse the usefulness of the Spanish translation of this instrument to predict poor outcomes. METHODS: A prospective blind study was conducted including 65 patients undergoing spine surgery. We created two groups of patients based on DRAM score: not distressed (NDRAM) or distressed (DDRAM). A visual analogue scale for pain and the 12-Item Short Form Health Survey (SF-12) were used at baseline, 6 weeks and 6 months. RESULTS: 24 patients were classified as DDRAM and 38 as NDRAM, with 3 patients not completing the questionnaires. The analysis found no significant differences in the demographic or clinical variables at baseline. At 6 weeks and 6 months, the NDRAM group showed improvements in low back pain (p < 0.001; p = 0.005), leg pain (p < 0.001; p = 0.017), physical health (p = 0.031; p = 0.003) and mental health (p = 0.137; p = 0.049). In contrast, in the DDRAM group, though leg pain score improved (p < 0.001; p = 0.002), there was no improvement at 6 weeks or 6 months in low back pain (p = 0.108; p = 0.287), physical health (p = 0.620; p = 0.263) or mental health (p = 0.185; p = 0.329). CONCLUSIONS: In our setting, the DRAM is a useful screening tool, and it has allowed the creation of a program between psychiatry and spine surgery.

11.
An Pediatr (Engl Ed) ; 93(3): 161-169, 2020 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-32111552

RESUMO

OBJECTIVES: To describe preventive, diagnostic and therapeutic strategies regarding necrotising enterocolitis in Spain and to identify the strengths, areas of further improvement, and future research lines. METHODS: Two questionnaires on the management of preterm infants less than 32 weeks, at risk of, or with diagnosed necrotising enterocolitis, were distributed among selected representatives of the surgeons and neonatologists of the Spanish Neonatal Network (SEN1500) participant hospitals with a Paediatric Surgery Department. RESULTS: Percentage of response was 77.1% of contacted surgeons and 88.6% of neonatologists. There is a written protocol on the diagnosis and medical management of necrotising enterocolitis in 52% of the hospitals, and as regards surgical treatment in 33%. There is wide access to donor bank milk and to staff dedicated to breastfeeding promotion (87%). On the contrary, only 52% of the centres perform delayed cord clamping, and probiotics are used in just 23%. The use of abdominal ultrasound is increasing. There are no large differences as regards duration of antibiotic use and bowel rest, whereas there was as regards antibiotic selection, surgical indication, and type of intervention. CONCLUSIONS: As regards prevention, delayed cord clamping and extended access to donor milk are two possible aspects of further improvement. The observed discrepancies noted in diagnostic and therapeutic aspects are common in precisely the areas where evidence in the literature is weakest.


Assuntos
Enterocolite Necrosante/terapia , Neonatologistas/estatística & dados numéricos , Cirurgiões/estatística & dados numéricos , Antibacterianos/administração & dosagem , Estudos Transversais , Enterocolite Necrosante/diagnóstico , Enterocolite Necrosante/prevenção & controle , Pesquisas sobre Atenção à Saúde , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Bancos de Leite Humano/provisão & distribuição , Probióticos/administração & dosagem , Espanha
12.
J Neurosurg Pediatr ; : 1-11, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31561226

RESUMO

OBJECTIVE: The authors hypothesized that new agents such as BioGlue would be as efficacious as kaolin in the induction of hydrocephalus in fetal sheep. METHODS: This study was performed in 34 fetal lambs randomly divided into 2 studies. In the first study, fetuses received kaolin, BioGlue (2.0 mL), or Onyx injected into the cisterna magna, or no injection (control group) between E85 and E90. In the second study, fetuses received 2.0-mL or 2.5-mL injections of BioGlue into the cisterna magna between E85 and E90. Fetuses were monitored using ultrasound to assess lateral ventricle size and progression of hydrocephalus. The fetuses were delivered (E120-E125) and euthanized for histological analysis. Selected brain sections were stained for ionized calcium binding adaptor 1 (Iba1) and glial fibrillary acidic protein (GFAP) to assess the presence and activation of microglia and astroglia, respectively. Statistical comparisons were performed with Student's t-test for 2 determinations and ANOVA 1-way and 2-way repeated measures for multiple determinations. RESULTS: At 30 days after injection, the lateral ventricles were larger in all 3 groups that had undergone injection than in controls (mean diameter in controls 3.76 ± 0.05 mm, n = 5). However, dilatation was greater in the fetuses injected with 2 mL of BioGlue (11.34 ± 4.76 mm, n = 11) than in those injected with kaolin (6.4 ± 0.98 mm, n = 7) or Onyx (5.7 ± 0.31 mm, n = 6) (ANOVA, *p ≤ 0.0001). Fetuses injected with 2.0 mL or 2.5 mL of BioGlue showed the same ventricle dilatation but it appeared earlier (at 10 days postinjection) in those injected with 2.5 mL. The critical threshold of ventricle dilatation was 0.1 for all the groups, and only the BioGlue 2.0 mL and BioGlue 2.5 mL groups exceeded this critical value (at 30 days and 18 days after injection, respectively) (ANOVA, *p ≤ 0.0001). Moderate to severe hydrocephalus with corpus callosum disruption was observed in all experimental groups. All experimental groups showed ventriculomegaly with significant microgliosis and astrogliosis in the subventricular zone around the lateral ventricles. Only kaolin resulted in significant microgliosis in the fourth ventricle area (ANOVA, *p ≤ 0.005). CONCLUSIONS: The results of these studies demonstrate that BioGlue is more effective than Onyx or kaolin for inducing hydrocephalus in the fetal lamb and results in a volume-related response by obstructive space-occupancy without local neuroinflammatory reaction. This novel use of BioGlue generates a model with potential for new insights into hydrocephalus pathology and the development of therapeutics in obstructive hydrocephalus. In addition, this model allows for the study of acute and chronic obstructive hydrocephalus by using different BioGlue volumes for intracisternal injection.

13.
Eur J Pediatr Surg ; 29(1): 23-27, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30086576

RESUMO

AIM: Extrahepatic portal vein obstruction (EHPVO) is a frequent cause of noncirrhotic portal hypertension in children. The aim of this study is to analyze long-term results after diversion surgery. PATIENTS AND METHODS: Retrospective review of EHPVO patients who underwent diversion surgery analyzing number of platelets, leukocytes, prothrombin activity, splenomegaly, and gastrointestinal bleeding 10 years after surgery. RESULTS: Thirty-three patients were evaluated, mostly males (64%) and presenting with gastrointestinal bleeding (46%). Mesoportal shunt (Rex) was performed in 19 patients, mesocaval in 7, distal splenorenal in 7, and proximal splenorenal in 3. While comparing mesoportal shunt to the other portosystemic shunts, an increase in platelets was found with every technique, but it was clearly higher in mesoportal shunt. The highest increase was 6 months after surgery (p = 0.0015) as well as prothrombin activity (p = 0.0003). Leukocytes level also increased without statistical significance. Spleen size (cm) and spleen size Z score (SSAZ) decreased significantly 6 months after mesoportal shunt (p = 0.0168). Before surgery, over 94% patients suffered gastrointestinal bleeding, which reduced significantly afterward with bleeding episodes in only four (12%) of them. CONCLUSION: Diversion surgery in EHPVO, especially mesoportal shunt of Rex, improves hepatic function (prothrombin activity), reduces hypersplenism (platelets, leukocytes, and spleen size), and decreases gastrointestinal bleeding episodes.


Assuntos
Veia Porta/cirurgia , Derivação Portossistêmica Cirúrgica , Doenças Vasculares/cirurgia , Adolescente , Criança , Pré-Escolar , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/prevenção & controle , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Hipertensão Portal/etiologia , Lactente , Contagem de Leucócitos , Masculino , Contagem de Plaquetas , Derivação Portocava Cirúrgica , Protrombina/metabolismo , Estudos Retrospectivos , Esplenomegalia/etiologia , Esplenomegalia/prevenção & controle , Derivação Esplenorrenal Cirúrgica , Resultado do Tratamento , Doenças Vasculares/complicações
14.
Eur J Pediatr Surg ; 29(1): 28-32, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30086577

RESUMO

AIM: Hepatoblastoma is the most frequent hepatic tumor in children, and its initial presentation will affect treatment and prognosis. The aim of this study is to evaluate long-term results of liver transplantation in children with unresectable hepatoblastoma. PATIENTS AND METHODS: This is a retrospective review of patients with hepatoblastoma who underwent liver transplantation, analyzing risk factors, tumor presentation, treatment, and long-term survival to identify prognostic factors. RESULTS: Thirty-one patients underwent liver transplantation in the context of unresectable hepatoblastoma, mainly males (67%) and with risk factors such as prematurity (12.9%), maternal smoking (6.5%), and familial adenomatous polyposis (3.2%). Most frequent presentation was multifocal PRETEXT III (51.6%) and PRETEXT IV (45.2%), with metastasis at diagnosis in 12.9% and vascular involvement in 54.8%.Twenty-one patients received a living-donor (67.7%) and 10 a cadaveric graft (32.2%), at 31.7 months of age (5-125). Most transplants were primary, and only two were performed as rescue therapy after an attempt of surgical resection of the tumor.Overall survival 1 and 5 years after transplantation were 93.3% ± 4.6% and 86.4% ± 6.3%, respectively. We could not find any statistically significant differences between risk factors, tumor presentation, type of graft, or type of transplant. CONCLUSION: Liver transplantation has increased hepatoblastoma survival in unresectable tumors. Probably due to these good results, we have not been able to find significant prognostic factors in this cohort.


Assuntos
Hepatoblastoma/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Polipose Adenomatosa do Colo , Cadáver , Quimioterapia Adjuvante , Pré-Escolar , Feminino , Seguimentos , Hepatoblastoma/mortalidade , Hepatoblastoma/patologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Doadores Vivos , Masculino , Comportamento Materno , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fumar , Análise de Sobrevida
15.
Sci Rep ; 8(1): 10638, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30006626

RESUMO

Spina bifida aperta is a congenital malformation characterized by the failure of neural tube closure resulting in an unprotected fetal spinal cord. The spinal cord then undergoes progressive damage, likely due to chemical and mechanical factors related to exposure to the intrauterine environment. Astrogliosis in exposed spinal cords has been described in animal models of spina bifida during embryonic life but its relationship with neuroinflammatory processes are completely unknown. Using a retinoic acid-induced rat model of spina bifida we demonstrated that, when exposed to amniotic fluid, fetal spinal cords showed progressive astrogliosis with neuronal loss at mid-gestation (E15) compared to unexposed spinal cords. The number of microglial cells with a reactive phenotype and activation marker expression increased during gestation and exhibited progressive disruption in the inhibitory immune ligand-receptor system. Specifically we demonstrate down-regulation of CD200 expression and up-regulation of CD200R. Exposed spinal cords demonstrated neuroinflammation with increased tissue water content and cytokine production by the end of gestation (E20), which correlated with active Caspase3 expression in the exposed layers. Our findings provide new evidence that microglia activation, including the disruption of the endogenous inhibitory system (CD200-CD200R), may participate in the pathogenesis of spina bifida through late gestation.


Assuntos
Líquido Amniótico/imunologia , Antígenos CD/metabolismo , Microglia/metabolismo , Receptores Imunológicos/metabolismo , Espinha Bífida Cística/imunologia , Líquido Amniótico/metabolismo , Animais , Antígenos CD/imunologia , Caspase 3/imunologia , Caspase 3/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Embrião de Mamíferos , Feminino , Humanos , Microglia/imunologia , Gravidez , Ratos , Ratos Sprague-Dawley , Receptores Imunológicos/imunologia , Espinha Bífida Cística/induzido quimicamente , Espinha Bífida Cística/patologia , Medula Espinal/citologia , Medula Espinal/imunologia , Medula Espinal/patologia , Tretinoína/toxicidade , Regulação para Cima
16.
European J Pediatr Surg Rep ; 6(1): e18-e22, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29473012

RESUMO

Introduction Minimally invasive repair for pectus excavatum (MIRPE) is controversial in extremely severe cases of pectus excavatum (PE) and an open repair is usually favored. Our aim is to describe a case of a patient with an extremely severe PE that underwent a minimally invasive approach. Case report An 8-year-old girl with severe sternum depression was assessed. She had a history of exercise intolerance, nocturnal dyspnea, fatigue, and shortness of breath. Chest computed tomography showed that sternum depression was posterior to the anterior vertebral column; therefore, Haller and correction index could not be measured. Spirometry indicated an obstructive ventilation pattern (forced expiratory volume in 1 second = 74.4%), and echocardiogram revealed a dilated inferior vena cava, mitral valve prolapse with normal ventricular function. After multidisciplinary committee evaluation, a MIRPE approach was performed. All symptoms had disappeared at the 3-month postoperative follow-up; the desired sternum shape was achieved and normalization of cardiopulmonary function was observed. The Nuss bars were removed after a 2-year period. After 18-month follow-up, the patient can carry out normal exercise and is content with the cosmetic result. Conclusion Nuss procedure is feasible in our 8-year-old patient. In this case, both the Haller and correction index were not useful to assess the severity of PE. Therefore, under these circumstances, other radiologic parameters have to be taken into consideration for patient evaluation.

17.
Eur J Pediatr Surg ; 28(1): 34-38, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28759900

RESUMO

AIM: Cardiac function can be impaired in patients with pectus excavatum (PE) due to anatomic and dynamic compression of the heart. Efforts for radiation dose reduction in imaging techniques have allowed cardiac magnetic resonance imaging (c-MRI) to play a major role in PE assessment. The aim of our study is to describe the findings of c-MRI 18 months after we changed the PE assessment protocol from chest computed tomography to c-MRI. PATIENTS AND METHODS: Since mid-2015 all patients with severe PE (suspected Haller's index > 3.2) were assessed with inspiratory and expiratory c-MRI. A retrospective analysis of these patients was performed evaluating the following parameters: (1) Radiologic PE indexes (Haller's, correction and asymmetry indexes; and sternal rotation) and (2) cardiac function (including left and right ventricle ejection fraction). RESULTS: A total of 20 patients met the inclusion criteria. Dynamic imaging showed a significant difference during inspiration and expiration of the Haller's index 3.85 (range: 3.17-7.3) versus 5.10 (range: 3.85-10.8) (p < 0.05), and correction index (26.86% vs. 36.84%, respectively, p < 0.05). The sternal rotation was 14.5 (range: 0-36). c-MRI analysis disclosed a right ventricle ejection fraction of 50.3%. (normal range: 61% [54-71%]). Echocardiographic imaging underestimated the functional repercussion of PE in all patients. CONCLUSION: Initial results show that PE assessment by c-MRI allows a radiation-free image of the chest wall deformity during the entire breathing process. Also, it permitted the evaluation of the influence of sternum impingement on cardiac function. These findings allowed us a careful surgical evaluation and preoperative planning.


Assuntos
Tórax em Funil/fisiopatologia , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Criança , Ecocardiografia , Feminino , Tórax em Funil/diagnóstico por imagem , Coração/fisiopatologia , Humanos , Masculino , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
18.
Materials (Basel) ; 10(2)2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28772464

RESUMO

The preparation of composites of synthetic and natural polymers represent an interesting option to combine properties; in this manner, polypropylene and chitosan extruded films using a different proportion of components and polypropylene-graft-maleic anhydride (PPgMA) as compatibilizer were prepared. The effect of the content of the biopolymer in the polypropylene (PP) matrix, the addition of compatibilizer, and the particle size on the properties of the composites was analyzed using characterization by fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), tensile strength, and contact angle, finding that in general, the addition of the compatibilizer and reducing the particle size of the chitosan, favored the physicochemical and morphological properties of the films.

19.
Carbohydr Polym ; 155: 117-127, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27702495

RESUMO

Chitosan was functionalized with epigallocatechin gallate (EGCG) by a free radical-induced grafting procedure, which was carried out by a redox pair (ascorbic acid/hydrogen peroxide) as the radical initiator. The successful preparation of EGCG grafted-chitosan was verified by spectroscopic (UV, FTIR and XPS) and thermal (DSC and TGA) analyses. The degree of grafting of phenolic compounds onto the chitosan was determined by the Folin-Ciocalteu procedure. Additionally, the biological activities (antioxidant and antibacterial) of pure EGCG, blank chitosan and EGCG grafted-chitosan were evaluated. The spectroscopic and thermal results indicate chitosan functionalization with EGCG; the EGCG content was 25.8mg/g of EGCG grafted-chitosan. The antibacterial activity of the EGCG grafted-chitosan was increased compared to pure EGCG or blank chitosan against S. aureus and Pseudomonas sp. (p<0.05). Additionally, EGCG grafted-chitosan showed higher antioxidant activity than blank chitosan. These results indicate that EGCG grafted-chitosan might be useful in active food packaging.


Assuntos
Antibacterianos/química , Catequina/análogos & derivados , Quitosana/química , Antioxidantes , Catequina/química , Radicais Livres , Pseudomonas/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
20.
Eur J Pediatr Surg ; 27(1): 16-19, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27723922

RESUMO

Aim Hepatocellular carcinoma (HCC), although being infrequent, is the second-most common primary hepatic malignancy in children, after hepatoblastoma (HB). The prognosis is very poor. We present our series of children with HCC referred to our transplant unit to be assessed as candidates for liver transplantation (LT). Methods A retrospective review of HCCs referred to our transplant unit in the past 20 years (1994-2015) was performed. Age at diagnosis, disease-free survival, location of recurrence, initial treatment, secondary treatment, and mortality were noted. Main Results Ten patients (8 boys, 2 girls) met the inclusion criteria. Median age at diagnosis was 11.5 years (0.5-14). HCC was associated with tyrosinemia in two patients, while the tumor developed in absence of previous liver disease in eight. Seven children attempted tumor resection earlier elsewhere. LT was not considered suitable in six patients due to extrahepatic tumor extension and finally it was performed in four (two with tyrosinemia and two with "de novo" HCC). Only one of the transplants was primary, and the other three were performed as rescue therapy. After 78 (66-90) months of follow-up, the two patients with tyrosinemia remain alive and disease free, while the other two had distant relapses, 35 and 37 months after LT, respectively, and finally died due to tumor progression. Conclusions HCC is a rare, very aggressive tumor in children who has a very poor prognosis. Our results suggest the need for new strategies. Early referral of all cases to highly specialized centers with a liver transplant unit and perhaps a more liberal use of LT, even for selected, apparently resectable cases, are possible options.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Adolescente , Carcinoma Hepatocelular/mortalidade , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Neoplasias Hepáticas/mortalidade , Masculino , Encaminhamento e Consulta , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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