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1.
Pediatr Int ; 61(10): 1020-1024, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31282046

RESUMO

BACKGROUND: Thyroglossal duct cyst (TDC) is the most common congenital abnormality in the neck in children. The purpose of this study was to perform a comprehensive review of all cases of TDC surgically treated at a single institution and to evaluate the factors that influence the rate of recurrence, and the aesthetic outcome of the surgery on follow up. METHODS: All cases of TDC surgically treated at the Department of Pediatric Surgery at Meyer Hospital from January 2005 to December 2016 were selected. Charts from 248 patients were reviewed and risk factors for recurrence evaluated. A questionnaire was submitted to the patients' parents to determine if postoperative complications were present  and standardized neck pictures were requested, to evaluate the cosmetic result . Microsoft Office Excel 2007 for Windows and Graphpad Prism 6 were used for data management and statistical analysis. RESULTS: Simple cyst excision and post-inflammatory fibrosis (P < 0.05) were assessed as important risk factors for the recurrence of TDC. Recurrence rate on Sistrunk procedure was 5%. Variables such as post-inflammatory fibrosis before surgery (P < 0.001), the positioning of a drain (P < 0.01) and the development of recurrence (P < 0.001), negatively influenced the cosmetic result. No thyroglossal duct cyst carcinoma and no long-term postoperative complications were observed. CONCLUSIONS: Recurrence rates were higher in patients who underwent simple cyst excision instead of the Sistrunk procedure, as already reported in literature. Presence of post-inflammatory fibrosis and positioning of the drain at surgery were associated with higher rates of recurrence, as well as worse cosmetic outcome.


Assuntos
Cisto Tireoglosso/cirurgia , Adolescente , Criança , Pré-Escolar , Cicatriz/epidemiologia , Cicatriz/etiologia , Estética , Feminino , Seguimentos , Humanos , Lactente , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Recidiva , Fatores de Risco , Resultado do Tratamento
2.
Int J Mol Sci ; 20(19)2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31623362

RESUMO

Skeletal muscle regeneration is ensured by satellite cells (SC), which upon activation undergo self-renewal and myogenesis. The correct sequence of healing events may be offset by inflammatory and/or fibrotic factors able to promote fibrosis and consequent muscle wasting. Angiotensin-II (Ang) is an effector peptide of the renin angiotensin system (RAS), of which the direct role in human SCs (hSCs) is still controversial. Based on the hypertrophic and fibrogenic effects of Ang via transient receptor potential canonical (TRPC) channels in cardiac and renal tissues, we hypothesized a similar axis in hSCs. Toward this aim, we demonstrated that hSCs respond to acute Ang stimulation, dose-dependently enhancing p-mTOR, p-AKT, p-ERK1/2 and p-P38. Additionally, sub-acute Ang conditioning increased cell size and promoted trans-differentiation into myofibroblasts. To provide a mechanistic hypothesis on TRPC channel involvement in the processes, we proved that TRPC channels mediate a basal calcium entry into hSCs that is stimulated by acute Ang and strongly amplified by sub-chronic Ang conditioning. Altogether, these findings demonstrate that Ang induces a fate shift of hSCs into myofibroblasts and provide a basis to support a benefit of RAS and TRPC channel blockade to oppose muscle fibrosis.


Assuntos
Angiotensina II/metabolismo , Transdiferenciação Celular , Miofibroblastos/metabolismo , Células Satélites de Músculo Esquelético/metabolismo , Transdução de Sinais , Angiotensina II/farmacologia , Sinalização do Cálcio , Sobrevivência Celular/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Humanos , Hipertrofia , Imagem Molecular , Mioblastos/citologia , Mioblastos/metabolismo , Miofibroblastos/citologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
3.
Fetal Pediatr Pathol ; 37(4): 263-269, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30188242

RESUMO

INTRODUCTION: Lymphangiomas are benign tumors/malformations, characterized by proliferation of the lymphatic vessels. They may arise anywhere, although the most common localizations are the head-neck region and the axilla. To date, only 21 cases of lymphangioma of the ovary in a 60-year literature survey have been reported. CASE REPORT: A 16-year-old female patient with long standing abdominal distension had 40 cm × 15 cm × 29 cm ovarian lymphangioma. CONCLUSIONS: Our case highlights that lymphangiomas can occur in the adolescent population and should be added to the differential diagnosis of ovarian masses in this age group.


Assuntos
Linfangioma/patologia , Neoplasias Ovarianas/patologia , Adolescente , Feminino , Humanos
4.
Gynecol Endocrinol ; 32(10): 787-791, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27250513

RESUMO

This study analyzes updated clinical, diagnostic, and surgical directions for the treatment of ovarian neoplasms in children and adolescents, comparing them with a retrospective analysis of 32 cases treated in two Pediatric Surgery University Institutions. From January 2005 to December 2015, 32 pediatric patients were surgically treated for 32 ovarian tumors: 28 (87.5%) benign and 4 (12.5%) malignant neoplastic lesions. Median age at surgery was 11.2 years (12.8 years in patients with benign neoplasms, 7.25 years in patients with malignant ones). All patients with malignant and 25% of patients with benign ovarian lesions had elevated serum level of tumors markers. The surgical approach was laparotomic in 62.5% and laparoscopic in 37.5%; 81.2% surgeries were performed in elective surgery and 18.8% in emergency. Intraoperative frozen section analysis was performed in 18.75% of patients. The most frequent surgery (96.8%) was unilateral oophorectomy. After a median follow-up of 76 months (range 6-132 months), 31/32 patients are alive and disease-free. In case of malignant tumors, fertility-sparing surgery with accurate staging must be performed. Laparoscopic multiport is the gold standard approach for benign pediatric ovarian neoplasms, but the use of laparoscopy in full respect of oncological principles also for early stage malignant tumors is currently increased.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/métodos , Laparoscopia/métodos , Neoplasias Ovarianas/cirurgia , Adolescente , Criança , Feminino , Seguimentos , Humanos , Resultado do Tratamento
5.
Pediatr Int ; 58(7): 601-3, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27072876

RESUMO

Thoraco-abdominal trauma can in rare cases involve diaphragmatic rupture and subsequent herniation of intra-abdominal contents. We report a case of this complication in a 5-year-old boy who was injured in a car crash, and who manifested respiratory distress and hemodynamic instability after 48 h of being monitored in the pediatric intensive care unit. Multiple radiologic investigations were inconclusive and the definite diagnosis was established only on thoracoscopic exploration.


Assuntos
Diafragma/diagnóstico por imagem , Hérnia Diafragmática Traumática/diagnóstico , Herniorrafia/métodos , Toracoscopia/métodos , Pré-Escolar , Diafragma/lesões , Hérnia Diafragmática Traumática/cirurgia , Humanos , Masculino , Tomografia Computadorizada por Raios X
6.
Pediatr Int ; 57(4): 724-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25869095

RESUMO

Cystic lesions deriving from the omentum are rare benign clinical conditions of uncertain etiopathogenesis. In this report we describe a case of antenatal diagnosed intra-abdominal cystic mass, which, due to the absence of symptomatology and constant ultrasound morphology over time, did not require immediate treatment. The present patient was followed up until surgery, which was performed at 4 years of age: on laparoscopy a cyst within the greater omentum was identified and excised. Histopathology indicated a cyst with epidermoid structure, which is unusual among the omental cysts reported in the literature.


Assuntos
Cisto Epidérmico/diagnóstico , Omento/patologia , Doenças Peritoneais/diagnóstico , Pré-Escolar , Cisto Epidérmico/cirurgia , Humanos , Recém-Nascido , Laparoscopia , Doenças Peritoneais/cirurgia
7.
Pediatr Hematol Oncol ; 32(3): 199-206, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24274683

RESUMO

In this study, we analyze the management of ovarian masses in a total of 130 children surgically treated for 137 ovarian lesions (7 bilateral). The most frequent symptoms were chronic (52.3%) and acute (25.4%) abdominal pain. Histological examination revealed 64 (46.7%) functional lesions, 59 (43.1%) benign neoplasms, 5 (3.7%) malignant ones, and 7 (6.6%) torsed normal ovaries. Ovarian torsion occurred in 36 cases (26.27%). A conservative treatment was performed in 81 (59.1%) girls: 61 (75.3%) treated in nonemergency and 20 (24.7%) in emergency surgery; laparoscopic approach in 35 cases (43.2%); and open surgery in 46 (56.8%). The remaining 56 (40.9%) ovarian masses underwent nonconservative surgery: 40 cases (71.4%) nonemergency and 16 (28.6%) emergency; laparoscopy in 20 patients (35.7%); and open surgery in 36 (64.3%). Fertility preservation should be a goal in the surgical treatment. The management of ovarian torsion should include adnexal detorsion and recovery of the ovarian tissue. In case of benign neoplasms, laparoscopic tumorectomy should be the gold standard; in early stage malignant tumors, fertility-sparing surgery with accurate staging is preferred.


Assuntos
Neoplasias Ovarianas/cirurgia , Adolescente , Biomarcadores Tumorais/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/diagnóstico por imagem , Ovariectomia , Estudos Retrospectivos , Anormalidade Torcional/cirurgia , Ultrassonografia
8.
Aesthetic Plast Surg ; 39(3): 414-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25762154

RESUMO

UNLABELLED: The umbilicus has a paramount aesthetical function for the abdomen and when removed due to a surgical procedure, an umbilicoplasty is mandatory: indeed, its absence could contribute to the development of psychological disorders, especially in childhood. Herein, we describe a straightforward technique to obtain a seemingly natural umbilical scar. This technique, easily taught in a general pediatric surgery environment, may be amenable for any kind of umbilical reconstruction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Granuloma/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Umbigo/cirurgia , Úraco/cirurgia , Cicatrização/fisiologia , Pré-Escolar , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/cirurgia , Feminino , Seguimentos , Granuloma/patologia , Humanos , Técnicas de Sutura , Fatores de Tempo , Resultado do Tratamento , Umbigo/fisiopatologia , Úraco/anormalidades
9.
Fetal Pediatr Pathol ; 34(1): 65-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25329248

RESUMO

Cervical thymic cysts are rare cervical masses which usually present in the first decade of life accounting for 0.3% - 1% of all congenital neck masses. Due to its rarity thymic cysts are seldom included in the differential diagnosis of cystic cervical mass and are often mistaken for more common conditions such as branchial cleft cyst or cystic hygroma. Herein we present a case of a 6-year-old girl with a right lateral cervical cystic mass with multiple septae extended from mandibular angle along the neurovascular bundle of the neck which revealed to be a thymic cyst at histopathology.


Assuntos
Neoplasias do Timo/diagnóstico por imagem , Neoplasias do Timo/diagnóstico , Criança , Colesterol/química , Cistos/diagnóstico , Cistos/diagnóstico por imagem , Cistos/patologia , Cistos/cirurgia , Diagnóstico Diferencial , Feminino , Granuloma/diagnóstico , Granuloma/diagnóstico por imagem , Humanos , Linfócitos/citologia , Imageamento por Ressonância Magnética , Mandíbula/patologia , Pescoço/patologia , Timo/patologia , Neoplasias do Timo/cirurgia , Ultrassonografia , Nervo Vago/patologia
10.
FASEB J ; 27(12): 4853-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23995291

RESUMO

Functional smooth muscle engineering requires isolation and expansion of smooth muscle cells (SMCs), and this process is particularly challenging for visceral smooth muscle tissue where progenitor cells have not been clearly identified. Herein we showed for the first time that efficient SMCs can be obtained from human amniotic fluid stem cells (hAFSCs). Clonal lines were generated from c-kit(+) hAFSCs. Differentiation toward SM lineage (SMhAFSCs) was obtained using a medium conditioned by PDGF-BB and TGF-ß1. Molecular assays revealed higher level of α smooth muscle actin (α-SMA), desmin, calponin, and smoothelin in SMhAFSCs when compared to hAFSCs. Ultrastructural analysis demonstrated that SMhAFSCs also presented in the cytoplasm increased intermediate filaments, dense bodies, and glycogen deposits like SMCs. SMhAFSC metabolism evaluated via mass spectrometry showed higher glucose oxidation and an enhanced response to mitogenic stimuli in comparison to hAFSCs. Patch clamp of transduced hAFSCs with lentiviral vectors encoding ZsGreen under the control of the α-SMA promoter was performed demonstrating that SMhAFSCs retained a smooth muscle cell-like electrophysiological fingerprint. Eventually SMhAFSCs contractility was evident both at single cell level and on a collagen gel. In conclusion, we showed here that hAFSCs under selective culture conditions are able to give rise to functional SMCs.


Assuntos
Líquido Amniótico/citologia , Diferenciação Celular , Linhagem da Célula , Células-Tronco Fetais/citologia , Células-Tronco Multipotentes/citologia , Miócitos de Músculo Liso/citologia , Actinas/genética , Actinas/metabolismo , Potenciais de Ação , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Meios de Cultivo Condicionados/farmacologia , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Desmina/genética , Desmina/metabolismo , Células-Tronco Fetais/efeitos dos fármacos , Células-Tronco Fetais/metabolismo , Células-Tronco Fetais/fisiologia , Glucose/metabolismo , Glicogênio/metabolismo , Humanos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Células-Tronco Multipotentes/efeitos dos fármacos , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/fisiologia , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Calponinas
11.
Sensors (Basel) ; 14(10): 18096-113, 2014 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-25268912

RESUMO

Pectus Excavatum is an anatomical deformation characterized by a depression of the anterior chest wall. Nuss technique (representing the current clinical golden standard) consists in the introduction of a corrective metal bar, in order to raise the sternum in its anatomic natural position. Nowadays, the bar plays purely a mechanical/corrective action and is kept implanted for about three years, supporting up to a maximum force of 250 N. Our study aims at optimizing the procedure of correction, in terms of monitoring the bar effect, minimizing the body response, and facilitating the bar removal. The sensorized Nuss bar prototype inserted in a platform for telemedicine described in this article is able to monitor in vitro pressure data variations, with more than 150 discrete measurements during the operating period. This behavior is promising for future clinical applications, in which the device could be exploited to monitor the forces at work, thus, providing a customized therapeutic protocol, which in turn may optimize the period of implant. The sensorized bar was also provided with a polymeric coating, able to influence human dermal fibroblast behavior in vitro. This highlights the possibility to minimize, in future in vivo applications, tissue fibrotic responses.


Assuntos
Tórax em Funil/cirurgia , Próteses e Implantes , Telemedicina , Parede Torácica/cirurgia , Tórax em Funil/patologia , Humanos , Complicações Pós-Operatórias , Parede Torácica/patologia
12.
Waste Manag ; 175: 101-109, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38194795

RESUMO

This study aims at valorizing the residual aqueous phase from hydrothermal carbonization (HTC) of Sicilian agro-wastes in order to enhance the hydrochar recovery, positively affecting the process energy balance. Process waters (PW) obtained from HTC and co-HTC using orange peel waste and fennel plant residues were used as recycled solvent in experiments carried out at the temperatures of 180 and 230 °C. The results showed that an additional hydrochar formation was promoted during recirculation of solvent, leading to average increments of solid mass yield of 10.5 wt% for tests conducted at 180 °C and 3.9 wt% for 230 °C. After five consecutive recirculation phases in co-HTC runs, the hydrochar yield increased up to 18.2 wt%. The low H/C and O/C atomic ratios values, found after recirculation, indicate that organic acids, accumulated in the PW, may catalyze the process and promote the biomass deoxygenation by boosting dehydration and decarboxylation. The recovered PWs from conversion steps with deionized water were also carbonized in absence of the solid feedstock in order to quantify their contribution in hydrochar formation during recirculation and thus the synergistic interactions. After recirculation, energy recovery averagely augmented by more than threefold, showing that the proposed strategy could significantly improve the sustainability of HTC.


Assuntos
Conservação de Recursos Energéticos , Água , Carbono/química , Temperatura , Solventes
13.
Gynecol Endocrinol ; 29(1): 54-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22817767

RESUMO

The purpose of this study is to discuss the surgical treatment for ovarian torsion in children and adolescents with a focus on the procedures of adnexal conservation surgery and its frequency in the literature of the last 10 years. We retrospectively reviewed the medical charts of 127 operative ovarian lesions including 30 ovarian torsions (23.6%) treated in two pediatric centers over a 10-year period. Age at presentation, presenting symptoms, diagnostic studies, surgical procedure and pathological findings were analyzed. Mean age was 13.7 years. Conservative surgery has been performed in 46.7% of the cases and laparoscopic approach in 40%. Ovarian torsion occurred in 56.7% on ovaries with functional lesion, in 23.3% on normal adnexa and in 20% on ovaries with benign neoplasm. The article includes a literature review (2000-2010) and a statistical analysis which shows a slow increase in conservative surgery from 28 to 45%. Laparoscopic surgery accounts for 23.5%. Literature review shows 40.5% normal adnexa, 33.2% non-neoplastic lesions, 25.3% benign neoplasms and 1% malignant neoplasms. The surgical treatment of children and adolescents presenting adnexal torsion should be practiced as an emergency and it should be more conservative as possible in order to maximize the future reproductive potential.


Assuntos
Anexos Uterinos/cirurgia , Doenças dos Anexos/cirurgia , Doenças Ovarianas/cirurgia , Neoplasias Ovarianas/cirurgia , Anormalidade Torcional/cirurgia , Doença Aguda , Anexos Uterinos/patologia , Doenças dos Anexos/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Laparoscopia , Doenças Ovarianas/patologia , Neoplasias Ovarianas/patologia , Estudos Retrospectivos , Anormalidade Torcional/patologia
14.
Emerg Med J ; 30(3): e15, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22492125

RESUMO

STUDY OBJECTIVE: The Meyer Pediatric Hospital in Florence, Italy recently implemented the single provider model of emergency medicine. Prior to these changes, patients were triaged to a paediatric surgeon or paediatrician based on the complaint. The authors assess the outcomes of patients evaluated by surgeons prior to this change and compare them with those of patients seen by emergency physicians. METHODS: A retrospective, cohort study was performed reviewing patients seen in the emergency department between 2005 and 2008 for the three most common surgical complaints encountered before the systems change: head trauma, testicular pain and abdominal pain. Outcomes include misdiagnoses, consultation rates, dispositions, imaging, interventions and surgeries. RESULTS: A total of 2415 patient visits were included. Emergency physicians saw more patients (1388 vs 1027) and obtained more consultations (25.6% vs 8.1%) than surgeons. Patients triaged directly to surgeons were more likely to be admitted to the hospital (10.3% vs 7.6%), undergo urgent interventions (9.5% vs 6.7%), undergo surgery (8.0% vs 4.8%), have more radiographic images to evaluate head trauma (12.1% vs 5.3%), be misdiagnosed (1.0% vs 0.3%) and have more plain films for abdominal pain (3.1% vs 1.3%). There is an overall trend towards fewer missed diagnoses by emergency physicians (0.3% vs 0.9%), but this difference is only statistically significant in the abdominal pain subset analysis (p=0.032, combined data p=0.052). CONCLUSIONS: The single provider model of emergency medicine where emergency physicians manage all patients presenting to the emergency department appears to be a safe and efficient model of emergency medical care.


Assuntos
Serviço Hospitalar de Emergência , Hospitais Pediátricos , Modelos Organizacionais , Dor Abdominal/diagnóstico , Dor Abdominal/terapia , Distribuição de Qui-Quadrado , Criança , Traumatismos Craniocerebrais/diagnóstico , Traumatismos Craniocerebrais/terapia , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Itália , Masculino , Padrões de Prática Médica/estatística & dados numéricos , Estudos Retrospectivos , Doenças Testiculares/diagnóstico , Doenças Testiculares/terapia , Triagem , Recursos Humanos
15.
Sensors (Basel) ; 13(4): 4390-403, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23549364

RESUMO

The increasing development of smart materials, such as piezoelectric and shape memory alloys, has opened new opportunities for improving repair techniques. Particularly, active repairs, based on the converse piezoelectric effect, can increase the life of a structure by reducing the crack opening. A deep characterization of the electromechanical behavior of delaminated composite structures, actively repaired by piezoelectric patches, can be achieved by considering the adhesive layer between the host structure and the repair and by taking into account the frictional contact between the crack surfaces. In this paper, Boundary Element (BE) analyses performed on delaminated composite structures repaired by active piezoelectric patches are presented. A two-dimensional boundary integral formulation for piezoelectric solids based on the multi-domain technique to model the composite host damaged structures and the bonded piezoelectric patches is employed. An interface spring model is also implemented to take into account the finite stiffness of the bonding layers and to model the frictional contact between the delamination surfaces, by means of an iterative procedure. The effect of the adhesive between the plies of piezoelectric bimorph devices on the electromechanical response is first pointed out for both sensing and actuating behavior. Then, the effect of the frictional contact condition on the fracture mechanics behavior of actively repaired delaminated composite structures is investigated.

16.
Front Chem ; 11: 1132464, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874067

RESUMO

The aim of this study is to synthesize cheap and highly ordered CaO from cuttlefish bone (CFB) as a green alternative to conventional adsorbents such as activated carbon. This study focuses on the synthesis of highly ordered CaO via calcination of CFB, at two different temperatures (900 and 1000°C) and two holding times (0.5 and 1 h), as a potential green route for water remediation. The as-prepared highly ordered CaO was tested as an adsorbent using methylene blue (MB) as a model compound for dye contaminants in water. Different CaO adsorbent doses (0.05, 0.2, 0.4, and 0.6 g) were used, keeping the MB concentration fixed at 10 mg/L. The morphology and crystalline structure of the CFB before and after calcination was characterized via scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses, while the thermal behavior and surface functionalities were characterized by thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy, respectively. Adsorption experiments using different doses of CaO synthesized at 900°C for 0.5 h showed an MB removal efficiency as high as 98% by weight using 0.4 g (adsorbent)/L(solution). Two different adsorption models, the Langmuir adsorption model and the Freundlich adsorption model, along with pseudo-first-order and pseudo-second-order kinetic models, were studied to correlate the adsorption data. The removal of MB via highly ordered CaO adsorption was better modeled by the Langmuir adsorption isotherm giving (R2 =0.93), thus proving a monolayer adsorption mechanism following pseudo-second-order kinetics (R2= 0.98), confirming that chemisorption reaction occurs between the MB dye molecule and CaO.

17.
Waste Manag ; 169: 125-136, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37423054

RESUMO

In this study, the chlorine mitigation from waste polyvinyl chloride (WPVC) during high temperature co-hydrothermal treatment (co-HTT) and the properties of the generated solid products were assessed. WPVC was co-fed with acidic hydrochar (AHC), which was produced via hydrothermal carbonization of pineapple waste in the presence of citric acid water solution. High temperature co-HTT experiments were performed at 300-350 °C, 0.25-4 h of reaction time, and 0-20 wt% AHC loading. Co-HTT solid products (co-HTT_SP) were characterized via proximate analysis, ultimate analyses, combustion analysis, and ash analysis. The results show that the addition of 5% AHC enhances the dechlorination efficiency (DE) of WPVC from 89.35% to 97.66% at 325 °C and 0.5 h. The highest DE, reaching 99.46%, was achieved at 350 °C and 1 h in the presence of 5 wt% AHC. Furthermore, loading 5% AHC improved the higher heat value (HHV) of the solid products from 23.09 to 31.25 MJ/kg at 325 °C and 0.5 h. The maximum HHV (34.77 MJ/kg) of a solid product was achieved at 350 °C, 4 h, in the presence of 5 wt% of AHC. The co-HTT solids shown low slagging indices, fouling indices, alkali indices, and medium chlorine contents. These findings support the viability of WPVC conversion into clean solid fuel via co-HTT.


Assuntos
Carbono , Cloro , Temperatura , Temperatura Alta , Cloreto de Polivinila , Resíduos Sólidos
18.
Sci Total Environ ; 871: 162138, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773912

RESUMO

Hydrochar is a new carbonaceous product obtained via hydrothermal carbonization of wet biomass, such as sludges or digested sludges, which often have disposal problems, also due to the presence of contaminants such as heavy metals. The properties of the hydrochar led to an interest in using it as an amendment, but the agro-environmental properties must be considered for its safe use. Raw hydrochar produced by agro-industrial digestate and relative three acidic post-treated hydrochars (for heavy metals removal) have been assessed considering their effect on phytotoxicity, soil, plant growth, mutagenicity, and genotoxicity. The chemical characterization showed the effect of post-treatment on heavy metals contents reduction, except for Cu content (hydrochar, 650 mg/kg; post-treated hydrochars, 940 mg/kg, 287 mg/kg, and 420 mg/kg). The acidic post-treatment also reduces the phytotoxicity compared to raw hydrochar (the germination index at 16 % of hydrochar concentration was: hydrochar, 61.48 %; post-treated hydrochars, 82.27 %, 58.28 %, and 82.26 %), but the low pH and the impact on N-cycle probably have caused the detrimental effect on plant growth of post-treated hydrochar. No mutagenic activity was observed in bacteria using Ames test, while all the samples induced chromosomal aberrations in plant cells (Allium cepa test). The approach adopted, which considers phytotoxicity, plant growth-soil effects, and mutagenicity/genotoxicity bioassays has been proven effective for a proper evaluation of organic products derived from waste to promote a sustainable and circular recovery of materials.


Assuntos
Alcaloides , Metais Pesados , Esgotos , Metais Pesados/toxicidade , Solo , Biomassa , Carbono
19.
Ann Surg Oncol ; 19(6): 1766-73, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22322957

RESUMO

PURPOSE: The purpose of this study was to detect the role of serum tumor markers in the differential diagnosis and in the choice of the surgical treatment of ovarian lesions in pediatric age. METHODS: We retrospectively reviewed medical charts of all pediatric girls operated in two pediatric centers during a 10-year period. The following features were analyzed: age at the moment of presentation, symptoms, diagnostic studies, surgical approach, pathological findings, and, in particular, serum tumor markers. Also, a literature review and statistical analysis (χ(2) test) concerning the increase of different tumor markers in benign and malignant ovarian lesions were related to the study. RESULTS: A total of 120 children with 127 ovarian masses (7 with bilateral pathologies) were reviewed. Pathology showed 61 nonneoplastic lesions (48%), 54 benign tumors (42.5%), 5 malignant tumors (4%), and 7 torsed normal ovaries (5.5%). The evaluation of serum tumor markers was performed in 106 cases and was positive in 16 (15.1%): in all of the 5 cases (100%) of malignant neoplastic lesions and in 11 (20.4%) benign neoplastic ones. The literature review confirmed these data, and statistical analysis highlighted them as significant values. CONCLUSIONS: The role of tumor markers is still controversial. This is the reason why, before considering a radical treatment, we suggest caution to optimize future fertility.


Assuntos
Biomarcadores Tumorais/análise , Cistos Ovarianos/diagnóstico , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Laparoscopia , Cistos Ovarianos/cirurgia , Neoplasias Ovarianas/classificação , Prognóstico , Estudos Retrospectivos , Literatura de Revisão como Assunto , Fatores de Tempo , Ultrassonografia
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