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1.
Analyst ; 149(12): 3302-3308, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38747517

RESUMO

The contamination of environmental sites due to the presence of persistent species represents an important issue to be tackled. In particular, the presence of high levels of metals in soil and surface water is more frequent. One of the metals that sometimes exceeds the permissible limit set by regulatory authorities is copper. For instance, copper-based fungicides are widely used in viticulture. However, copper ions remain in soil and can enter the food chain, posing threats to human health and environmental safety. Although the rapid detection of copper ions using portable sensors is effective in enhancing early warning, it sometimes solves only half of the problem as remediation is not considered. In this paper, we present a novel integrated/portable approach that merges the remediation and sensing of metals by proposing a remediate-and-sense concept. In order to realize this concept, alginate beads were coupled with printed electrochemical strips for on-site copper detection. Within the same architecture, alginate beads were used to remove copper ions from the soil, and printed electrochemical strips were used to evaluate the efficacy of remediation at the point of need. The concept was applied towards soil containing copper ions at the parts per billion level; with few alginate beads and in the absence of additional species, copper ions were quantitatively removed from the matrix; and 3D printing allowed us to combine the printed strips and spheres within a unique tool. The architecture was optimized and the results were compared to inductively coupled plasma-mass spectrometry (ICP-MS) measurements with a recovery percentage of 90%-110%. It should be noted that this novel portable approach may be applied to other pollutants, opening new possibilities for integrated remediation and sensing.

2.
Emerg Radiol ; 28(4): 845-856, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33683517

RESUMO

Ingestion of caustic substances, whether accidental or for the purpose of suicide, can cause severe lesions of the lips, oral cavity, pharynx, upper gastrointestinal system, and upper airways. In particular, caustic agents could be responsible for severe esophageal injuries resulting in short- and long-term complications. Because of these important clinical implications, timely diagnosis and appropriate management are crucial. In the evaluation of esophageal injuries, thoraco-abdominal computed tomography (CT) is preferable to endoscopy as it avoids the risk of esophageal perforation and allows the evaluation of esophageal injuries as well as of the surrounding tissue. In this review, we report CT findings of esophageal injuries and possible related thoracic complications caused by caustic ingestion.


Assuntos
Traumatismos Abdominais , Queimaduras Químicas , Cáusticos , Queimaduras Químicas/diagnóstico por imagem , Cáusticos/toxicidade , Ingestão de Alimentos , Humanos , Tomografia Computadorizada por Raios X
3.
J Clin Med ; 12(6)2023 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-36983199

RESUMO

To date, the exact pathophysiology of haemorrhoids is poorly understood. The different philosophies on haemorrhoids aetiology may lead to different approaches of treatment. A pathogenic theory involving a correlation between altered anal canal microflora, local inflammation, and muscular dyssynergia is proposed through an extensive review of the literature. Since the middle of the twentieth century, three main theories exist: (1) the varicose vein theory, (2) the vascular hyperplasia theory, and (3) the concept of a sliding anal lining. These phenomena determine changes in the connective tissue (linked to inflammation), including loss of organization, muscular hypertrophy, fragmentation of the anal subepithelial muscle and the elastin component, and vascular changes, including abnormal venous dilatation and vascular thrombosis. Recent studies have reported a possible involvement of gut microbiota in gut motility alteration. Furthermore, dysbiosis seems to represent the leading cause of bowel mucosa inflammation in any intestinal district. The alteration of the gut microbioma in the anorectal district could be responsible for haemorrhoids and other anorectal disorders. A deeper knowledge of the gut microbiota in anorectal disorders lays the basis for unveiling the roles of these various gut microbiota components in anorectal disorder pathogenesis and being conductive to instructing future therapeutics. The therapeutic strategy of antibiotics, prebiotics, probiotics, and fecal microbiota transplantation will benefit the effective application of precision microbiome manipulation in anorectal disorders.

4.
Electrophoresis ; 32(10): 1176-81, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21500206

RESUMO

The copper(II) complex of a modified cyclodextrin, namely 6-mono-deoxy-6-[4-(2-aminoethyl)imidazolyl]-ß-CD (CDmh), previously synthesized and characterized in our laboratory and already used as chiral selector for ligand exchange capillary electrophoresis (LECE) with optical detection, is investigated here in LECE using electrospray-mass spectrometry (ESI-MS) as the detection device. The potential of this hyphenated method is compared with the results previously obtained with optical detection by studying the chiral resolution of tryptophan racemate. Chiral separation conditions compatible with LECE-ESI-MS could be achieved based on the figures of merit obtained by LECE-UV. Interestingly, the values of LOD obtained by LECE-ESI-MS were significantly better than those obtained by LECE-UV and thus, ESI-MS detection seems to open new perspectives in chiral separations by LECE.


Assuntos
Eletroforese Capilar/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Complexos de Coordenação/química , Cobre/química , Imidazóis/química , Ligantes , Sensibilidade e Especificidade , Estereoisomerismo , Triptofano/química , beta-Ciclodextrinas/química
5.
J Sep Sci ; 34(1): 70-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21171178

RESUMO

The diaminotrehalose-capped derivative of ß-CD, a new member of hemispherodextrins, was synthesized and characterized by NMR spectroscopy. Its protonation constants were determined by potentiometry, and the inclusion of both the enantiomers of dansyl-phenylalanine was investigated by NMR spectroscopy. Its stereoselective properties were exploited in electrokinetic chromatography by separating four enantiomeric pairs of dansyl derivatives of amino acids.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Trealose/química , Trealose/síntese química , beta-Ciclodextrinas/química , beta-Ciclodextrinas/síntese química , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Termodinâmica
6.
J Med Case Rep ; 13(1): 43, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30798788

RESUMO

INTRODUCTION: Hepatic abscess can be defined as an encapsulated collection of suppurative material within the liver parenchyma. Hepatic abscess can be distinguished as pyogenic, amebic, or fungal. Biliary tract disease remains the most common cause of hepatic abscess today, and the most common complications range from pleural effusion, empyema, and bronchohepatic fistula to subphrenic abscess and rupture into the peritoneal cavity, stomach, colon, vena cava, or kidney. A large abscess compressing the inferior vena cava and the hepatic veins may result in Budd-Chiari syndrome. In this report, we present a rare case of hepatic abscess with an unusual evolution that was treated with a noninvasive approach. CASE PRESENTATION: A 79-year-old Caucasian woman underwent endoscopic bile stone extraction and laparoscopic cholecystectomy. Six months later, a hepatic abscess in association with bilateral effusion was diagnosed. The prompt imaging-guided drainage solved the case. Three years later, she came to our attention complaining of dull, diffuse abdominal pain and high body temperature (38 °C). A retroperitoneal abscess was diagnosed that was spreading to the right lateral wall of the abdomen and extending across the muscular wall to the subcutaneous layer. The fluid collection also involved the right pleural cavity, forming an empyema. Also in this case, an imaging-guided drainage was performed, and the patient's clinical picture resolved in a few days. The retroperitoneal abscess recurred 14 months later, and it was dealt with using the same treatment. Three months from the last follow-up, the patient came back to our attention with an evident swelling of her right lumbar region. Computed tomography revealed a right inferior lumbar hernia comprising adipose tissue and the right kidney. A surgical intervention was recommended to the patient, but, owing to her poor general health, she refused any invasive approach. CONCLUSIONS: Retroperitoneal abscess is an uncommon complication of biliary tract surgery and represents a potential cause of death, especially in those patients with multiple diseases. Prompt drainage is crucial to the treatment. Failure in eliminating the primary infective focus could bring complications and, in general, a weakness of lumbar muscular wall, even resulting in a rare case of lumbar hernia.


Assuntos
Procedimentos Cirúrgicos do Sistema Biliar , Hérnia Abdominal/complicações , Hérnia Abdominal/diagnóstico por imagem , Abscesso Hepático/complicações , Abscesso Hepático/terapia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/terapia , Idoso , Diagnóstico Diferencial , Drenagem , Feminino , Humanos , Abscesso Hepático/diagnóstico por imagem , Região Lombossacral/diagnóstico por imagem , Recidiva , Espaço Retroperitoneal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
7.
J Chromatogr A ; 1179(1): 17-23, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-17942104

RESUMO

The possibility of using capillary electrophoresis-electrospray ionisation (ESI)/MS to separate and quantify cobalt and iron was explored. It was necessary to tackle and overcome problems from different sources, some of them being rather unpredictable. The results obtained suggest the occurrence of oxidation processes of metal ions during the formation of the electrospray. The quantitative oxidation of cobalt(II) to cobalt(III), a process at our knowledge never described before, appears particularly interesting. The results obtained, though not optimised for sensitivity appear promising, since a limit of detection of the order of tenths of picograms was obtained. Further, from the comparison with the results obtained by optical detection, the use of CE-ESI/MS appears advantageous.


Assuntos
Cobalto/análise , Eletroforese Capilar/métodos , Ferro/análise , Resorcinóis/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Cobalto/isolamento & purificação , Ferro/isolamento & purificação , Oxirredução
8.
Front Psychiatry ; 9: 636, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581393

RESUMO

Autism spectrum disorder (ASD) is currently diagnosed according to behavioral criteria. Biomarkers that identify children with ASD could lead to more accurate and early diagnosis. ASD is a complex disorder with multifactorial and heterogeneous etiology supporting recognition of biomarkers that identify patient subsets. We investigated an easily testable blood metabolic profile associated with ASD diagnosis using high throughput analyses of samples extracted from dried blood spots (DBS). A targeted panel of 45 ASD analytes including acyl-carnitines and amino acids extracted from DBS was examined in 83 children with ASD (60 males; age 6.06 ± 3.58, range: 2-10 years) and 79 matched, neurotypical (NT) control children (57 males; age 6.8 ± 4.11 years, range 2.5-11 years). Based on their chronological ages, participants were divided in two groups: younger or older than 5 years. Two-sided T-tests were used to identify significant differences in measured metabolite levels between groups. Näive Bayes algorithm trained on the identified metabolites was used to profile children with ASD vs. NT controls. Of the 45 analyzed metabolites, nine (20%) were significantly increased in ASD patients including the amino acid citrulline and acyl-carnitines C2, C4DC/C5OH, C10, C12, C14:2, C16, C16:1, C18:1 (P: < 0.001). Näive Bayes algorithm using acyl-carnitine metabolites which were identified as significantly abnormal showed the highest performances for classifying ASD in children younger than 5 years (n: 42; mean age 3.26 ± 0.89) with 72.3% sensitivity (95% CI: 71.3;73.9), 72.1% specificity (95% CI: 71.2;72.9) and a diagnostic odds ratio 11.25 (95% CI: 9.47;17.7). Re-test analyses as a measure of validity showed an accuracy of 73% in children with ASD aged ≤ 5 years. This easily testable, non-invasive profile in DBS may support recognition of metabolic ASD individuals aged ≤ 5 years and represents a potential complementary tool to improve diagnosis at earlier stages of ASD development.

9.
J Pharm Biomed Anal ; 37(5): 1009-14, 2005 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-15862680

RESUMO

6-O-Succinil-beta-cyclodextrin (CDsuc6) was synthesized with very good yield by one pot synthesis and characterized by NMR spectroscopy and ESI-MS. It was used as a chiral selector in capillary electrophoresis to resolve catecholamine racemates, namely norepinephrine, epinephrine, terbutaline and norphenilephrine. The CE experiments at pH 5.6 show very promising selector ability by 6-O-succinil-beta-cyclodextrin for the chiral recognition of all the catecholamines tested, while at pH 9.2, only racemic terbutaline was successfully separated.


Assuntos
Ácido Succínico/análise , Ácido Succínico/química , beta-Ciclodextrinas/análise , beta-Ciclodextrinas/química , Cromatografia/métodos , Ciclodextrinas/análise , Eletroquímica , Conformação Molecular
10.
J Chromatogr A ; 979(1-2): 137-45, 2002 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-12498242

RESUMO

Six different racemates of the profen family were used as analytes in order to test the chiral selector properties of three members of a new class of cyclodextrin derivatives, hemispherodextrins (HMs), in capillary electrophoresis. In addition to experiments carried out to separate each enantiomeric pair one by one, other experiments were carried out on samples containing all six enantiomeric pairs. Electropherograms were obtained either by adding a single HM to the background electrolyte (BGE), or a binary mixture of HMs. The results obtained confirm the excellent chiral selector properties of the HMs, and furthermore show that these compounds can also be used for achiral selection. When mixing different HMs, a complementary effect in chiral selectivity is observed, which, in our opinion, deserves further study.


Assuntos
Dextrinas/isolamento & purificação , Eletroforese Capilar/métodos , Dextrinas/química , Estereoisomerismo
11.
J Pharm Biomed Anal ; 85: 55-60, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23892656

RESUMO

Two different chiral selectors synthesised in our laboratory were used to test the possibility of separation for a sample consisting of ten different enantiomeric pairs of dansyl-derivatives of α-amino acids in electrokinetic chromatography. It was possible to observe all the peaks, though only partly resolved, due to the twenty analytes through an accurate strategy of choice of the experimental conditions. As a part of this strategy, a procedure of identification of the single peaks in the electropherograms called LACI (lastly added component identification) has been developed.


Assuntos
Aminoácidos/análise , Cromatografia Capilar Eletrocinética Micelar/métodos , Compostos de Dansil/análise , Concentração de Íons de Hidrogênio , Cinética , Estereoisomerismo
12.
J Chromatogr A ; 1269: 360-5, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-22939205

RESUMO

Thirteen enantiomeric pairs of α-amino acids derivatised with fluorescein isothiocyanate (FITC-AAs) were separated in capillary electrophoresis (CE) using as chiral selectors the single isomer derivatives (SIDs) 3-monodeoxy-3-monoamino-ß- and γ-cyclodextrins. The chiral separation data obtained by these strictly homologous compounds, show different behaviours, allowing to hypothesise a possible structure of the obtained selector-analyte complexes, as well as highlighting the crucial role of the cavity size and the significant effects on the resolution obtained by small differences in the structural characteristics of these analytes.


Assuntos
Ciclodextrinas/química , Eletroforese Capilar/métodos , Fluoresceína-5-Isotiocianato/química , Estereoisomerismo
13.
J Chromatogr A ; 1217(7): 953-67, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-20022327

RESUMO

The review focuses on the role of ionic or ionisable single isomer derivatives (SIDs) of cyclodextrins on the separation of chiral analytes in capillary electrophoresis (CE), covering the period since the year 2000. The advantages of using pure compounds are discussed, as well as the ways to optimise the separations in the context of a rational approach to these techniques. Specific attention is paid to the modulation of the selector-analyte interaction. The advantage due to a detailed knowledge of equilibria occurring in solution during the CE run is underlined, particularly in the case of the presence of metal complexes, as occurs in chiral ligand exchange capillary electrophoresis (CLECE).


Assuntos
Ciclodextrinas/química , Eletroforese Capilar/métodos , Ânions/química , Cátions/química , Modelos Moleculares , Estereoisomerismo
14.
Electrophoresis ; 28(15): 2580-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17607805

RESUMO

A capped derivative of beta-CD (THALAH) was synthesized and characterized by NMR spectroscopy at different pH values. A trehalose moiety, bonded through beta-alanine bridges to the CD cavity, is included in the capping unit, giving peculiar properties to this molecule. The hemispherodextrin thus obtained was tested as a chiral selector in EKC. At neutral pH, the monocationic species of THALAH behaves as a very efficient selector separating successfully all the 11 tested enantiomeric pairs of dansyl-derivatives of amino acids, some of them even at concentrations as low as 0.15 mM. The differences observed in the migration order among the different systems give suggestions about the mechanism of molecular recognition between the selector and the analytes.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Dextrinas/síntese química , Espectroscopia de Ressonância Magnética , beta-Alanina/química , Aminoácidos/isolamento & purificação , Dextrinas/química , Concentração de Íons de Hidrogênio , Fosfatidilcolinas , Estereoisomerismo
15.
Electrophoresis ; 27(8): 1471-80, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16555341

RESUMO

Five pure CD derivatives synthesized in our laboratory were used as chiral selectors in the presence of copper(II) ion. Three enantiomeric pairs of amino acids were submitted to separation experiments in CE, by exploiting the ligand exchange mechanism. The results obtained in the investigated systems, together with those of the analogous systems previously studied, clearly show the usefulness of this technique in chiral separations. By comparing the ligand exchange CE results with potentiometric results, either reported elsewhere or studied here for the first time (system Cu/CDampy/tyrosine), it has been possible to rationalise the separation results. The importance of the availability of pure selectors, and to characterise them both spectroscopically and thermodynamically is discussed.


Assuntos
Aminoácidos/isolamento & purificação , Eletroforese Capilar/métodos , Aminopiridinas , Ciclodextrinas/química , Ligantes , Fenilalanina/análogos & derivados , Fenilalanina/isolamento & purificação , Estereoisomerismo , Triptofano/análogos & derivados , Triptofano/isolamento & purificação , Tirosina/análogos & derivados , Tirosina/isolamento & purificação , beta-Ciclodextrinas
16.
Dalton Trans ; (16): 2731-6, 2005 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16075113

RESUMO

The bis-amino AB derivative of beta-cyclodextrin on the secondary rim was synthesised and spectroscopically characterised by different techniques. Its binary systems both with protons and copper(II) were thermodynamically characterised by pH-metric potentiometry. In addition the ternary systems with each of the enantiomers of tryptophan and alanine were investigated. A thermodynamic stereoselectivity was observed for the tryptophan enantiomers and this was exploited to separate them by capillary electrophoresis through a ligand exchange mechanism (LECE). LECE separation of racemates of phenylalanine and tyrosine was also obtained.


Assuntos
Cobre/química , Compostos Organometálicos/síntese química , Termodinâmica , beta-Ciclodextrinas/química , Sítios de Ligação , Configuração de Carboidratos , Sequência de Carboidratos , Concentração de Íons de Hidrogênio , Ligantes , Dados de Sequência Molecular , Compostos Organometálicos/química , Estereoisomerismo
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