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1.
Sci Total Environ ; 863: 161051, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36549519

RESUMO

Plastics accumulate in the environment affecting biota and ecosystems. Although rivers are vectors of land-based plastics to the sea, macroplastics and microplastics in rivers are recently studied. Most studies focused on floating plastic transport to the sea through rivers considering only abiotic hydromorphological factors. In this view, among biotic factors, vegetation has recently been found to entrap plastics. Indeed, the role of vegetation is pivotal in affecting riverine plastic transport. While marine vegetation blocking plastics has been studied, research in freshwater ecosystems is neglected. Since hydrological factors have a pivotal role in riverine plastic transport and few is known on plant entrapment, the interaction between hydrological variables and plastic entrapment by vegetation has not yet been investigated. Given that the composition, transport, and fate of "submerged" plastics in the water column are neglected, we aimed at investigating the behaviour of plants in entrapping plastics within a specific laboratory flume tank. Specifically, we assessed whether (i) aquatic plants block different plastic sizes within the water column and (ii) different factors (e.g. water level, density of plants) affect plastic entrapment. Our results showed that, according to plant density, the higher the plant density the higher the entrapment of plastics by plants - independently of plastic size. Considering the water level, macro-, meso-, and microplastics were trapped similarly. Moreover, Potamogeton crispus blocked fewer microplastics compared with Myriophyllum spicatum. Our results might have impact as plants acted as temporary plastic trappers and can be used as tools for mitigating plastic pollution. Future research might investigate if this laboratory approach can be applied in field for recollecting plastics and consequently mitigating the problem. In conclusion, good management of plants in watercourses, canals, and rivers should be ideal for enhancing river functionality and ecosystem services for human well-being (i.e. the plastic entrapment service by plants).


Assuntos
Plásticos , Poluentes Químicos da Água , Humanos , Microplásticos , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Rios , Água
2.
Int J Pharm ; 625: 122102, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35961419

RESUMO

Pentamidine (PTM) is an aromatic diamidine approved for the treatment of parasitic infections that has been recently proposed for possible repositioning as an anticancer drug. To this aim, efforts have been made to improve its therapeutic efficacy and reduce associated adverse effects through both covalent derivatization and association with nanocarriers. To efficiently encapsulate PTM into biocompatible nanoparticles and to enhance its selectivity toward cancer cells, a squalene (SQ) derivative (1,1',2-tris-norsqualenoic acid, SQ-COOH) was selected to prepare PTM-loaded nanocarriers. Indeed, SQ and its derivatives self-assemble into nanoparticles in aqueous media. Furthermore, SQ-bioconjugates strongly interact with low-density lipoproteins (LDL), thus favoring preferential accumulation in cells overexpressing the LDL receptor (LDLR). We report here the preparation of nanocarriers by ion-pairing between the negatively charged SQ-COOH and the positively charged PTM free base (PTM-B), which allowed the covalent grafting of SQ to PTM to be avoided. The nanoparticles were characterized (mean size < 200 nm and zeta potential < -20 mV for SQ-COOH/PTM-B 3:1 molar ratio) and molecular modelling studies of the SQ-COOH/PTM-B interaction confirmed the nanocarrier stability. Finally, the ability to indirectly target LDLR-overexpressing cancer cells was evaluated by in vitro cell viability assays and confirmed by LDLR silencing, serum privation and simvastatin treatment.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sobrevivência Celular , Portadores de Fármacos/farmacologia , Neoplasias/tratamento farmacológico , Pentamidina/farmacologia , Esqualeno/farmacologia
3.
Chir Ital ; 46(3): 27-8, 1994.
Artigo em Italiano | MEDLINE | ID: mdl-8001190

RESUMO

Sarcomatoid carcinomas of the lung are uncommon neoplasms; the concurrent presence of malignant epithelial and sarcomatoid spindle cell components show a high malignancy. Lymph node metastases at presentation is an important prognostic factor, on the other way the most patients with sarcomatoid carcinoma of the lung usually presented at an advanced stage that needed a complementary therapy. The Authors report about one surgical case of pulmonary carcinosarcoma recently observed without lymph node metastases; the literature is reviewed and the histogenesis is discussed.


Assuntos
Carcinossarcoma/cirurgia , Neoplasias Pulmonares/cirurgia , Carcinossarcoma/diagnóstico por imagem , Carcinossarcoma/patologia , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
6.
Diagn Immunol ; 4(3): 145-8, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3731689

RESUMO

Salivary IgA (SlgA) levels were determined in 1,539 normal children, aged between 8 months and 6 years. In four children (0.26%), an absence and in 25 children (1.62%) a relative defect, (less than 1 mg/dl) were found. These values are similar to those encountered in an adult male population. Conversely, the mean SlgA in all age groups we examined was much lower in comparison to the adult mean. This difference is particularly great for SlgA and much smaller for total salivary proteins. There was no difference between males and females, and no relation with personal or familial history of allergic and/or infectious episodes. The conclusions of this study are as follows: Absolute and relative SlgA defects, when found, are present from birth, The complete maturation of SlgA occurs after 6 years of age, The role of SlgA in the protection against allergic or infectious episodes perhaps ought to be revised.


Assuntos
Imunoglobulina A Secretora/metabolismo , Saliva/imunologia , Fatores Etários , Criança , Pré-Escolar , Disgamaglobulinemia/imunologia , Feminino , Humanos , Hipersensibilidade/imunologia , Deficiência de IgA , Lactente , Infecções/imunologia , Masculino , Valores de Referência
7.
Chir Ital ; 36(2): 209-14, 1984 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-6525684

RESUMO

A case of leiomyoma of the small bowel which growth in the mesentery is reported. After review of the late literature, the Authors prove that this tumor is rare. The clinical examination and the simptoms associated with this neoplasm are aspecific for many months, so that X-ray as well as other complementary examinations are often necessary for the diagnosis.


Assuntos
Neoplasias do Jejuno/diagnóstico , Leiomioma/diagnóstico , Humanos , Neoplasias do Jejuno/patologia , Neoplasias do Jejuno/cirurgia , Leiomioma/patologia , Leiomioma/cirurgia , Masculino , Pessoa de Meia-Idade
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